Electrical activity and intraluminal pressure of the cauda epididymidis of the rat.

Smooth muscle electrical activity was recorded simultaneously with intraluminal pressure in the cauda epididymidis and epididymal vas of the rat in vitro. Spontaneous electrical activity spread over distances of several centimetres and was associated with a pressure wave recorded through an open-ended catheter in the distal cauda and epididymal vas. Transmission of pressure wave was gradually damped by filling of the catheter with spermatozoa.


A high molecular weight antifertility factor from human seminal plasma.

The presence of a high molecular weight antifertility factor in human seminal plasma was established. The factor can be precipitated by centrifugation at 104 000 g. Its activity is maximal when the protein concentration reaches 150 micrograms/10(5) spermatozoa using the mouse in-vitro fertilization assay as the test system. The factor is heat labile but its activity is not affected by dialysis. It prevents the penetration of the spermatozoa through the layers surrounding the egg but has no effect on the fusion of the spermatozoa with the vitelline membrane. The factor is only partly removed from spermatozoa by washing but is completely dispersed when the spermatozoa are incubated in capacitation medium. The pellet that is precipitated from the seminal plasma does not contain any particles or vesicles. However, it is significantly contaminated with low molecular weight material. This material includes the acrosin inhibitor which is present in large enough quantities to hinder fertilization. Washing the pellet twice with H2O removes these low molecular weight compounds, as indicated by the absence of the acrosin inhibitor, but has no effect on the antifertility properties of the pellet. Therefore, before further study or purification of the factor, it is essential that the pellet is washed such low molecular weight material. The washed pellet consists of at least 7 components as judged by disc gel electrophoresis.


Effect on gonadotrophin secretion of blockage of the ductuli efferentes in the normal and androgen-deprived rat.

Serum LH and FSH concentrations were measured in adult male rats. Blockage of the ductuli efferentes by surgical ligation or treatment with the anti-fertility drug alpha-chlorohydrin did not produce any changes in serum LH or androgen-dependent organ weights. Serum FSH in both groups was significantly raised by 4 days after treatment and remained so throughout most of the experimental period (42 days) but did not attain the values obtained in castrates. The gonadotrophin changes were accompanied by an initial increase in the weight and turgidity of the testes which then became flaccid and atrophied. These changes were similar but not identical after both treatments. Androgen secretion was impaired in adult rats treated with ethylene dimethane sulphonate; serum LH values were similar to those of 14-day castrates, and serum FSH was also elevated but not to the level found in the castrates. Ligation of the ductuli efferentes did not produce any further changes in concentrations of either hormone in spite of the retention of the testicular products within the testes as reflected by an increase in weight. The results are consistent with the view that changes in serum FSH after blockage of the ductuli efferentes are related to disturbances in the production of inhibin from the seminiferous epithelium rather than retention of inhibin with the testicular tubules.


Determination ob biologically active LH in the serum of male rheusus monkeys (Macaca mulatta).

The in-vitro bioassay for LH, using mouse Leydig cells, has been modified for the direct measurement of serum LH in the male rhesus monkey. Validation of the assay demonstrated good reliability in terms of accuracy, precision and sensitivity (1.5 mi.u./ml). Basal LH concentrations in laboratory-maintained monkeys with and without anaesthesia were not significantly different from those in free-ranging, feral monkeys. LH-RH (50 micrograms i.v.) elicited a 30-fold increase in LH concentrations after 30 min. LH levels in castrated adult monkeys were approximately 50 times the normal levels. Intact and castrated juvenile males had only very low LH levels. LH from the serum of an adult male castrate was further characterized by Sephadex G100 column chromatography. The in-vitro bioassay provides a preferable alternative to the heterologous radioimmunoassay method for the routine determination of LH in the rhesus monkey.


Nutrient requirements of rat embryos undergoing organogenesis in vitro.

Rat embryos at the head-fold stage were cultured in rotating bottles for 2 days in rat serum extensively dialysed against glucose-free BSS, and to which various energy sources and nutrients were added. Optimum growth and differentiation, virtually indentical with that obtained in while serum and to that seen during the corresponding period in vivo, were obtained with the addition of glucose and certain vitamins: pantothenic acid and riboflavin had a general beneficial effect on development, i-inositol suppressed neural tube defects, and folic acid significantly improved growth of the embryos.


Elemental composition of rabbit antral fluid during preovulatory follicular swelling.

Electron probe microanalysis was used to determine the concentrations of Na, Cl, K Ca, Mg, S and P in samples of follicular fluid, ovarian vein serum and peripheral venous serum obtained from virgin rabbits at 2-h intervals up to 10 h after injection of hCG. Throughout this 10-h period the elemental composition of follicular fluid was essentially the same as that of blood serum. However, there was a significant drop in follicular fluid Ca relative to blood during the 10-h period which may reflect Ca involvement in the regulation of oocyte maturation. Significant differences were also found between follicles within rabbits for K and P concentrations.


Changes in body weight, blood glucose and serum proteins in relation to the appearance of post-partum oestrus in Gir cows.

Of 16 cows, 9 did not exhibit oestrus within 90 days of parturition. These 9 cows had significantly lower body weights, blood glucose and serum protein concentrations than did the 7 cows which exhibited a fertile oestrus. It is suggested that these differences could be used to identify those cows which will not show an early post-partum oestrus.


Clinical use of plasma total estriol measurements in late pregnancy.

A critical review of the clinical use of measurements of plasma total estriol concentration in late pregnancy was done on the basis of one year's experience with the test at one institution which provides tertiary-level care to high-risk obstetric patients. The overall efficiency of the test in discriminating patients at risk was 59%. It appears to be most useful when a negative result provides some reassurance that the status of the fetus is satisfactory.


Results of the intensive perinatal management of very-low-birth-weight infants (501 to 1,500 grams).

In January 1975 at the University of Colorado Medical Center, a program of intensive intrapartum and neonatal care went into effect for all infants with expected birth weights of over 600 gm. Data are presented on the 187 infants weighing 501 to 1,000 gm born in 1975 to 1976. The 70 infants weighing 501 to 1,000 gm had a perinatal mortality of 65% and a neonatal mortality of 55%. The perinatal mortality of the 117 infants weighing 1,001 to 1,500 gm was 25% and the neonatal mortality 20%. Among the 501- to 1,000-gm infants, cesarean section for delivery of abnormal presentations resulted in a lower perinatal mortality than did vaginal delivery. Apgar scores were predictive of an improved chance of survival, but scores of three or less even at five minutes were associated with a 25% survival rate. Of those infants who did not survive the neonatal period, over 70% had died by 48 hours of life. These results were achieved without the use of beta-mimetic tocolytic agents to inhibit labor or long-acting corticosteroids to enhance pulmonary maturation. The improved survival of the infants weighing 1,500 gm or less when compared with infants of similar weights in preceding years is attributed to more intensive perinatal management of these mothers and their very-low-birth-weight infants.


4-Anilidopiperidine analgesics. 2. A study of the conformational aspects of the analgesic activity of the 4-anilidopiperidines utilizing isomeric N-substituted 3-(propananilido)nortropane analogues.

Relatively little information is available concerning the influence of conformational factors on the potent analgesic actions of the 4-anilidopiperidines. A series of N-substituted 3 alpha- and 3 beta-(propananilido)nortropanes have been designed, synthesized, and stereochemically characterized as semirigid analogues of the 4-anilidopiperidine analgesics in an attempt to study the influence of certain stereochemical factors on analgesia in this class of compounds. Conformational analysis of 3 alpha-propananilides (4) reveals a boat conformation for the preferred conformation of the piperidine ring of these tropane analogues. Evaluation of the analgesic potencies of the isomeric N-substituted 3-(propananilido)nortropanes of this study indicates greater potency for the 3 beta-(propananilido) isomers (5) with N-benzyl and N-phenethyl substitution as compared to the corresponding N-substituted 3 alpha-propananilides. Analysis of relative solubility differences among these isomers suggests that both structural and stereochemical influences predominate in affecting analgesic potency.


New antiarrhythmic agents. 1. Primary alpha-amino anilides.

Thirty-two alpha-amino anilides with various substituents in the aromatic ring and in the alpha position are described. Their abilities to protect mice against chloroform-induced fibrillation and to elicit toxicity were determined. Substitution of an alkyl or aryl group in the alpha position enhanced the antifibrillatory activity. In most cases, increased potency was accompanied by increased toxicity. Eleven compounds were tested in dogs with surgically induced myocardial infarction; most showed antiarrhythmic activity. 2-Aminopropiono-2',6'-xylidide, tocainide, was chosen for clinical investigation.


New antiarrhythmic agents. 2. Amide alkyl alpha-amino xylidides.

The synthesis of a series of N-alkyl 2-amino 2',6'-xylidides is described. The method involved coupling of the N-alkyl-2',6'-xylidine with the appropriate 2-haloacyl halide, followed by ammonolysis. Alternatively, alkylation of the 2-phthalimido 2',6'-xylidide with NaH and the alkyl halide followed by hydrazinolysis was used. All compounds were evaluated for their ability to protect mice against chloroform-induced ventricular fibrillation. The compounds were generally more potent antifibrillatory agents than the corresponding secondary amides. All were more potent than tocainide and several showed less CNS toxicity. Five compounds were further evaluated in dogs with ventricular arrhythmias resulting from myocardial infarction. N-Ethyl-2-aminoaceto-4'-propoxy-2',6'-xylidide was as potent as lidocaine and produced less CNS toxicity.


New antiarrhythmic agents. 3. Primary beta-amino anilides.

The synthesis and pharmacologic evaluation of primary beta-amino anilides, as well as comparisons with tocainide, lidocaine, and its beta homologue, are described. Substituted anilines were acylated with 3-bromoacyl chlorides and converted to the title compounds by direct amination or via 3-phthalimido anilides and subsequent hydrazinolysis. Alternatively, anilines were acylated with substituted acryloyl chlorides and the amines prepared by addition of ammonia to the double bond. The target compounds were evaluated for their ability to protect against chloroform-induced fibrillation in mice. All were found to have some antifibrillatory activity; several were more potent than tocainide, a compound in clinical trials as an oral antiarrhythmic drug. Four compounds were tested for their effects against ventricular arrhythmias in dogs with myocardial infarction. 3-Amino-2',6'-butyroxylidide (38) was found to be more potent and less CNS toxic than tocainide.


Reactions of 1,3-bis(2-chloroethyl)-1-nitrosourea and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea in aqueous solution.

Products formed from the reaction of two chloroethylnitrosoureas in neutral aqueous solution have been identified and quantified. Mixture components recovered after a 1-h incubation period accounted for 75--85% of the starting nitrosourea. Approximately 65--85% of the reaction products were formed by an initial cleavage of the nitrosourea to the proposed intermediates 2-chloroethyl azohydroxide and an isocyanate and by subsequent hydrolytic reactions. A minor pathway, 5--10% of products, involves denitrosation of the nitrosourea with oxazoline formation. Stable isotope labeling and mass spectrometry have been used to determine the reaction sequence and product origins. Reaction product identification has been made using high-performance LC isolation and comparison with synthetic material.


Comparative cytotoxic and biochemical effects of ligands and metal complexes of alpha-N-heterocyclic carboxaldehyde thiosemicarbazones.

Several alpha-N-heterocyclic carboxaldehyde thiosemicarbazones and their iron and copper complexes have been tested for their cytotoxicity and inhibiting activity against DNA synthesis under controlled metal conditions. No ligands show cytotoxicity against Ehrlich cells at the concentrations tested, while some iron and copper complexes are active. In contrast, the ligands inhibit DNA synthesis at much lower concentrations than used above. Similarly, the metal complexes are effective inhibitors at concentrations much below those necessary to demonstrate cytotoxicity. In addition, the iron complexes of 1-formylisoquinoline thiosemicarbazone, 2-formylpyridine thiosemicarbazone, and 4-methyl-5-amino-1-formylisoquinoline thiosemicarbazone were shown to be three- to sixfold more active than their free ligands as inhibitors of partially purified ribonucleotide reductase to which no iron has been added. The copper complex of 2-formylpyridine thiosemicarbazone was slightly more active than the free ligand against the reductase.


Potential antitumor agents. 31. Quantitative structure-activity relationships for the antileukemic bis(guanylhydrazones).

Certain L1210-active bis(guanylhydrazones) have structural and biological properties in common with the DNA minor groove binding, antileukemic, bisquaternary ammonium heterocycles. Monitoring of the DNA binding of the bis(guanylhydrazones), by fluorimetric quantitation of drug displacement of DNA-bound ethidium, shows that, like the bisquaternary salts, these agents bind more strongly to poly[d(A-T)] than poly[d(G-C)]. The drug concentrations necessary to inhibit L1210 DNA-dependent DNA polymerase in vitro by 50% (IC50) are linearly related to measures of drug-DNA binding with no preference for a particular primary sequence of DNA being evident. Mammalian toxicity of the bis(guanylhydrazones) is effectively modeled by a regression equation containing binomial terms in Rm values, used as a measure of agent lipophilic-hydrophilic balance, and the logarithms of the IC50 values.


Chance factors in studies of quantitative structure-activity relationships.

Multiple regression analysis is a basic statistical tool used for QSAR studies in drug design. However, there is a risk or arriving at fortuitous correlations when too many variables are screened relative to the number of available observations. In this regard, a critical distinction must be made between the number of variables screened for possible correlation and the number which actually appear in the regression equation. Using a modified Fortran stepwise multiple-regression analysis program, simulated QSAR studies employing random numbers were run for many different combinations of screened variables and observations. Under certain conditions, a substantial incidence of correlations with high r2 values were found, although the overall degree of chance correlation noted was less than that reported in a previous study. Analysis of the results has provided a basis for making judgements concerning the level of risk of encountering chance correlations for a wide range of combinations of observations and screened variables in QSAR studies using multiple-regression analysis. For illustrative purposes, some examples involving published QSAR studies have been considered and the reported correlations shown to be less significant than originally presented through the influence of unrecognized chance factors.


A preliminary structure-activity study of the mixed-function oxidase inhibitor 7,8-benzoflavone.

A series of substituted and structural analogues of 7,8-benzoflavone were examined for their ability to inhibit benzo[a]pyrene oxidation by the mixed-function oxidases found in hepatic microsomes prepared from 3-methylcholanthrene- and phenobarbital-induced rats. Of all the benzoflavones tested, only 6-amino-7,8-benzoflavone possessed significant inhibitory activity toward both classes of induced mixed-function oxidases. Parameters which were found to be necessary for maximal inhibitory activity were the maintenance of an unsubstituted or specifically substituted exocyclic phenyl group on position 2, the preservation of the pyran-4-one ring, and a 6 position which is either unsubstituted or substituted with an oxidizable moiety.


Syntheses and biological activities of 7 beta-methyl steroids.

The preparation of 7 beta-methyl-5 alpha-dihydrotestosterone acetate and its 2-thia-A-nor analogue is described. Biological evaluation shows that a 7 beta-Me largely decreases myotrophic-androgenic activity in both 5 alpha-dihydrotestosterone and the 2-thia-A nor analogue. Testing for antitumor activity shows that the reduction in breast tumor weight was not significant for either compound, but the final tumor size in the animals treated with 7 beta-methyl-2-thia-A nor steroid at 10 (mg/kg)/day was significantly reduced. The effects of 7 beta-Me steroids on the various organ weights are also described. The influence of 7 beta-Me substituent on the biological activities of androgens may be mediated through direct interaction of the substituent with the receptor surface in contact with the third dimension of the steroid molecule.


Steric effects of substituents on phenethylamine hallucinogens. 3,4-(Methylenedioxy)amphetamine analogues alkylated on the dioxole ring.

The compounds 1-(2-methyl-1,3-benzodioxol-5-yl)-2-aminopropane and 1-(2,2-dimethyl-1,3-benzodioxol-5-yl)-2-aminopropane were synthesized and evaluated for pharmacologic effects in mice. These can be viewed as analogues of the known psychotomimetic agent 3,4-(methylenedioxy)amphetamine (MDA). Their hydrochloride salts were compared with MDA for their ability to increase spontaneous motor activity and to elicit behavioral effects. The former compounds was MDA-like in action, while the latter was not. The results suggest that one face of the molecule must be free of steric bulk to possess activity.


Structure-activity relationship of aniline mustards acting against B-16 melanoma in mice.

A set of 23 aniline mustards [X-C6H4N(CH2CH2Cl)2] have been tested for their activity against B-16 melanoma in mice. The following quantitative structure-activity relationship (QSAR) correlates the data well: log 1/C = -2.06 sigma - 0.15 pi - 0.13 pi2 + 4.13 (r = 0.936). When this equation is compared with those formulated for aniline mustards acting against leukemia, it is found that log P0 (ideal lipophilicity) is higher for solid tumors. The QSAR brings out the unique activity of phenylalanine aniline mustard.


Allylic esters as potential antitumor agents. Derivatives and analogues of 2,3-bis(hydroxymethyl)-7-oxabicyclo[2.2.1]hept-2-ene.

Derivatives and analogues of 2,3-bis(hydroxymethyl)-7-oxabicyclo[2.2.1]hept-2-ene were synthesized. Of the compounds prepared, dimethyl 2,3-bis(acetoxymethyl)-7-oxabicyclo[2.2.1]hepta-2,5-diene-5,6-dicarboxylate (5) was the most potent in a leukemia L1210 tissue culture assay (93% inhibition at 10(-6) M). None of the compounds showed significant reproducible in vivo antileukemic activity.


Autosomal recessive sudden unexpected death in children probably caused by a cardiomyopathy associated with myopathy.

The propositus, who died suddenly at the age of 22 months, was investigated because of an unusual myopathy. Family history revealed two sisters and four cousins who had also died suddenly and unexpectedly. The finding of asymmetric septal hypertrophy by echocardiography in the propositus suggested that the cause of the sudden death in the relatives was an undetected cardiomyopathy accompanying a mild and often subclinical myopathy. The affected children were in two sibships and both sets of parents were first cousins. The mother of one sibship was the sister of the father of the other. It is suggested that a gene causes a mild autosomal recessive myopathy with cardiomyopathy that is often undiagnosed and usually ends in sudden unexpected death in the second year of life. The same gene may manifest on echocardiogram in some heterozygotes as asymmetric septal hypertrophy.


Heterochromatic polymorphism in spontaneous abortions.

Since the advent of C-banding as a routine diagnostic procedure, the significance of heterochromatic polymorphism has been questioned. Some workers have considered variations in heterochromatin in chromosomes 1 and 9 to be associated with fetal wastage, recurrent abortions, and abnormal phenotypes. Over a 15-month period, this laboratory made a study of the diagnostic significance of heterochromatic variants in 50 couples with a history of recurrent abortions. A control group of 50 couples with at least two normal children and no miscarriages was investigated simultaneously. The results indicated no significant difference in the heterochromatic regions between aborting and non-aborting couples.


Alpha-thalassaemia in Cyprus.

The frequency of alpha-thalassaemia in Cyprus was determined with studies of haemoglobin Bart's in 1200 Greek Cypriot and 132 Turkish Cypriot newborn babies. Of the Greek newborns, 12.4%, and of the Turkish newborns, 6.8% had raised Hb Bart's (from 0.6% to 12.9% of the total haemoglobin) suggesting that they were carriers of either alpha-thalassaemia-1 or alpha-thalassaemia-2 genes. The findings suggest that the population of Cyprus has the highest frequencies of alpha-thalassaemia among Caucasian people.


Prenatal diagnosis of beta-thalassaemia by fetal red cell concentration with anti-AB serum.

Prenatal diagnosis by globin chain synthesis analysis on fetal blood samples obtained by placental aspiration was performed in two pregnancies at risk for beta-thalassaemia. Since both fathers had blood group AB, and both mothers had group O, fetal red cell concentration from maternal-fetal mixtures was obtained with the aid of anti-AB serum. With this approach it was possible to carry out globin chain synthesis analysis with very small amounts of fetal blood. Heterozygous and normal genotypes were ascertained and confirmed after birth.


Benign familial haematuria in children from the Jewish communities of Israel: clinical and genetic studies.

Over 7 years, 130 children were referred for prolonged isolated haematuria of unknown cause. In 34 instances, haematuria was also found in one or more family members. In 23 of these families (18% of all referrals for isolated haematuria), investigation and follow-up, for periods of 5 to 10 years, of the index cases and of 56 haematuric relatives showed no evidence of renal disease and no other pathological findings. These subjects were diagnosed as having benign familial haematuria. The gene for benign familial haematuria is apparently transmitted as an autosomal dominant with reduced penetrance and variable expressivity. In Israel, the disorder seems to be more frequent among Jews of non-Ashkenazi descent than among those of European ancestry (Ashkenazim).


Non-progressive cerebellar ataxia, aplasia of pupillary zone of iris, and mental subnormality (Gillespie's syndrome) affecting 3 members of a non-consanguineous family in 2 generations.

A family is reported in which a brother and sister both showed non-progressive cerebellar ataxia, aplasia of the pupillary zone of the iris, and mild mental subnormality. These clinical findings were similar to those in two previous case reports. Despite the birth of an affected son to the affected sister, this family is considered to confirm autosomal recessive inheritance of this syndrome. The paternity of the mother's husband is supported by blood groups and biochemical markers and it is presumed that the husband is a heterozygote, even though no consanguinity could be detected.


Muscular dystrophy in an X; 1 translocation female suggests that Duchenne locus is on X chromosome short arm.

A unique combination of a Duchenne-like muscular dystrophy in a girl with a translocation-inversion rearrangement involving an X chromosome and a no 1 chromosome appeared as a result of both gene mutation and chromosome mutation in the mother. The X-autosome rearrangement would permit full expression of an X-linked recessive gene, such as that for Duchenne muscular dystrophy, in a female, and this would satisfactorily explain the characteristic Duchenne-like course of our patient's illness. The simultaneous de novo appearance of the Duchenne mutation and the X;1 rearrange suggests possible sites for the Duchenne locus on the X chromosome short arm (at Xp1106 or Xp2107).


Duchenne type muscular dystrophy and consanguinity: difficulties in pedigree analysis.

We report the case of a 2-year-old girl who had signs of Duchenne type muscular dystrophy on clinical, electromyographic, laboratory, and pathological examination. The parents of the child are first cousins. A brother and nephew of the mother also had Duchenne type muscular dystrophy. Karyotype analysis in the proband showed both X chromosomes to be morphologically normal. The mother had very high plasma CK levels, equivalent to those observed in carriers of the disease. We discuss different hypothetical mechanisms designed to account for the family pedigree.


A case of partial trisomy 17 resulting from X-autosomal translocation.

A case of partial trisomy 17 with partial monosomy X resulting from a maternal X-autosomal translocation t(X;17)(q13;q21) is presented. Three previously reported cases are reviewed and the phenotypic features of trisomy 17 are discussed.


18p--syndrome resulting from translocation (13a;18q) in a mildly affected adult male.

The patient was a 27-year-old male with short stature, borderline mental deficiency, strabismus, and a short fourth metacarpal. His karyotype showed deletion of the short arm of a chromosome 18 as the result of de novo fusion centric translocation between chromosomes 13 and 18 (45,XY, --13, --18, +t(13;18) (13qter yields cen yields 18qter).


Brachydactyly and polydactyly with dermal ridge dissociation and ridge hypoplasia.

A child with brachymesophalangy and postaxial postminimal polydactyly was found also to have dermal ridge dissociation and ridge hypoplasia. She was the second child of unaffected, unrelated parents and was born after a normal pregnancy and delivery. No previous report of a similar combination has been traced.


Relationships between performance in medical school and first postgraduate year.

Data from a longitudinal study of Jefferson Medical College graduates were analyzed to determine levels of clinical competence in the first postgraduate year and relationships between postgraduate ratings and performance during medical school. Ratings were obtained on knowledge, data-gathering skills, clinical judgement, and professional attitudes from the hospitals in which the graduates received their training. Significant relationships were found among three levels of performance in medical school and postgraduate ratings and in all four competence areas. Relationships were strongest at the highest and lowest performance levels. It is concluded that in a substantial number of cases good and poor performance in the first postgraduate year can be predicted on the basis of information already available to the medical school faculty.


Augmentation of clinical services in rural areas by health sciences students.

Over a five-year period 230 senior-level students in medicine, nursing, and pharmacy served in clinics located throughout five rural communities. Students participated in the development of the clinics and in the organization of services that otherwise would not have been delivered. Community-based preceptors helped integrate the students' learning about community processes. The project provided experiential learning and interdisciplinary interactions that were enthusiastically received by the students. Follow-up surveys suggested that the experience reinforced interest in eventual practice in rural areas and in interdisciplinary settings. The project demonstrated that students were able to provide clinical services which were useful and acceptable to the communities and which were supported by local practitioners.


Prison health and medical education.

Prison health has long been neglected as an area of serivice by organized medicine and a site for clinical education by health science centers. The University of New Mexico Health Science Center offers an elective, weekly clinical experience for preclinical medical students, senior nursing students, and senior pharmacy students at a prison facility in need of medical services. Students' reaction to the prison experience was strongly positive. Most developed empathy toward the inmates and a greater understanding of prison health problems. Inmates rated the student service highly and requested its continuation. This community health education experience has provided a noncontractual model of a university-prison health alliance.


The volunteer patient as an educational resource.

In this article the authors describe the contribution to health science teaching made by volunteer patients in a purely educational setting. Patients with documented illnesses volunteer to give their own history, to be examined, and frequently to provide feedback to students. The over 2,500 such volunteer patients who have participated in this program in a six-year period are enthusiastic and highly motivated. Significant educational benefits are achieved, including the assumption of teaching responsibilities by nonprofessionals. The fact that this large number of ambulatory patients is available suggests that the majority of patients in active treatment settings may also appreciate their opportunity to cooperate in the education of health science students.


Student performance in internal medicine: the effect of previous clerkship experience.

To test the assumption that students who have completed other clerkships are likely to perform better in internal medicine, the authors undertook a prospective study of 160 senior students from two classes. Groups of students with little or no senior clerkship experience before their internal medicine clerkship were compared with groups of students who had extensive clerkship experience in disciplines other than medicine. Groups were compared with respect to ward-performance scores and scores on identical multiple-choice examinations. Neither ward-performance nor multiple-choice scores revealed differences attributable to previous clerkship experience. It is concluded that despite areas of instruction and experience which overlap between medicine and other disciplines, previous clerkship experience apparently does not have a beneficial effect on student performance in internal medicine, as measured by these two commonly used methods of evaluation.


Chemical and biological properties of a purified lymphoreticular-stimulating fraction of Corynebacterium parvum (Propionibacterium acnes type I).

A method is described in which washed whole cells of Corynebacterium parvum were chemically and enzymatically extracted to remove cytoplasm and cell-wall lipids. The resultant insoluble cell-wall residue possessed lympho-reticular stimulating properties as measured by their ability to increase spleen weight and protect against tumour-cell challenge. Analysis of the final product by chromatography and infrared spectroscopy has shown it to consist of carbohydrate and peptidoglycan, both of which appear to be necessary for the activities measured.


Radioimmunoassay for antibodies to rubella virus and its ribonucleoprotein component.

IgA and IgG antibodies to the ribonucleoprotein component of rubella virus have been demonstrated by radioimmune precipitation in sera from patients with recent but not remote rubella infection. This observation suggests that a test for antibodies to the ribonucleoprotein component may provide additional evidence in the diagnosis of recent rubella infection.


Electron microscopy of the L-cycle in Bacillus licheniformis var. Endoparasiticus (Benedek).

Electronmicrographs of sections show that the L-phases of Bacillus licheniformis var. endoparasiticus (Benedek) simulate the various types of micro-organism described by previous workers as associated with ostensibly noninfective conditions, notably cancer and arthritis; e.g., mycoplasmas, mycobacteria, corynebacteria and actinomycetes. The stages of the L-cycle, from spheroplasts through smaller and larger 'diphtheroid' bacteria to the fully reverted sporogenous bacillus, differ from one another mainly in their degree of reconstitution of the cell envelopes. Occurrence in 'diphtheroids' of nonresistant, cell-wall-deficient spore-like bodies, confirms their relationship with the true sporing bacillus stage. Large, swollen forms appear to be mother cells of minute stages.


Relationship between sexual intercourse and urinary-tract infection in women attending a clinic for sexually transmitted diseases.

The prevalence of urinary-tract infection (UTI), diagnosed by examination of a single midstream urine from sexually active women was found to be 6.4%. Significant bacteriuria was most common in women who presented within 24 h of coitus but was not related to the number of sexual partners. UTI occurred significantly more often in women who presented within 4 days of intercourse than in women seen after a longer interval. Whether frequency of intercourse affects the prevalence of UTI remains to be determined.


Oerskovia species: rare opportunistic pathogens.

The second documented instance of opportunistic infection by member of the genus Oerskovia is reported. There is some evidence to suggest that this group of bacteria, which is extensively distributed in the soil, may be more closely associated with man than has hitherto been supposed.


A binding site model of membrane transport: binary and cooperative flows.

The flows of solute molecules in a membrane under the influence of concentration gradients are considered within the framework of classical physical theories. A lattice model is constructed in which the binding sites represent potential minima and the flows are regarded as a result of molecules' making discrete transitions between the binding sites. Expressions for two-component currents are derived from certain descriptions for the transition mechanism. Where the molecular movement is given the crudest description, permeability coefficients are identical for both components and there is no current coupling. Where the molecular movement is given some finer detail, the permeability coefficients differ and positive coupling of flows appears. Our result applies to a combination of flows of tracer and abundant species as well as, more generally, to any combination of flows of two components which are distinguishable yet kinetically similar. Also considered are binary currents whose transport mechanism is further controlled by allosteric cooperativity. Whether the cooperative control is short or long ranged, permeability coefficients and fluxes differ appreciably from those without cooperative control. Thus, unlike in the case of channel flow, current coupling here may be either positive or negative, depending on the strength and nature of cooperative coupling. Numerical evidence suggests that the permeability and coupling may have discontinuous behavior, possibly indicating the existence of phase transitions. Our lattice model, from which the formulations for the flows are obtained, is compatible with current concepts of membrane structure.


Hypertonic cryohemolysis of human red blood cells.

Hypertonic cryohemolysis of human erythrocytes is caused by incubation of the cells in hypertonic medium at a temperature of 20--50 degrees C (stage 1), with subsequent cooling to 0 degrees C (stage 2). In 0.86 M sucrose hemolysis increases, with increasing stage 1 temperature, whereas in 1 M NaCl cryohemolysis has a temperature optimum at a stage 1 temperature of about 30 degrees C. Cryohmeolysis is inhibited by preceding ATP depletion of the cells and by preincubation of the cells in hypertonic medium at 0 degrees C. In general, anesthetics inhibit cryohemolysis strongly. Only in 1 M NaCl at stage 1 temperatures in the range of 40--50 degrees C is cryohemolysis stimulated by these drugs, if present during the entire incubation period. This effect is abolished, however, when the anesthetic is added after prior incubation of the cells at 40--50 degrees C in 1 M NaCl. Ghost-bound ANS fluorescence indicates complicated conformation changes in the membrane structure during the various experimental stages leading to cryohemolysis. Some of the experimental results can be considered as examples of molecular hysteresis, thus indicating several different metastable structures of the membrane, under various experimental conditions. The described results support the working hypothesis of Green and Jung that the experimental procedure results in membrane protein damage, preventing normal adaptation of the membrane during cooling.


Anionic detergents as divalent cation ionophores across black lipid membranes.

Three ionic detergents commonly used in membrane-bound protein isolation and reconstitution experiments, SDS, cholate, and DOC, are shown to act as divalent cation ionophores when incorporated into black lipid membranes made from either oxidized cholesterol or a mixture of phosphatidylcholine and cholesterol (PC/cholesterol = 5:1 mg). At a concentration greater than or equal to 1 microM, SDS shows large selectivity differences between cations and anions and among the different cations tested (Ba2+, Ca2+, Sr2+, Mg2+, and Mn2+). Deoxycholate and cholate at concentrations greater than 4 X 10(-4) M and 10(-3) M, respectively, also act as divalent cation ionophores. The selectivity sequence measured for these two detergents is evidence for a strong ionic interaction between the divalent cation and the anionic charged groups on the detergent. In the case of cholate, the conductance depends on the third or fourth power of the cholate concentration and shows a linear dependence on CaCl2 concentration. The conductance for deoxycholate depends onthe sixth or seventh power of the DOC concentration and is also linearly dependent on the CaCl2 concentration. In an oxidized cholesterol black lipid membrane in the presence of 5 mM CaCl2, small concentrations of LaCl3 (less then 1 microM) inhibit the ionophoric activity of each of the detergents tested. Evidence is presented to show that this inhibitory effect is a nonspecific effect on oxidized cholesterol BLM's, and is not due to a direct effect of La3+ on detergent-mediated transport.


Saxitoxin binding to synaptosomes, membranes, and solubilized binding sites from rat brain.

Binding of 3H-saxitoxin to Na+ channels was studied in subcellular fractions prepared from rat brain homogenates. Saxitoxin binding to synaptosomes was saturable with an apparent dissociation constant of about 1 nM; about 1 pmol/mg protein was bound at saturating saxitoxin concentrations. A linear, nonsaturable component of saxitoxin binding accounted for less than 3% of the total binding at 30 nM. Saxitoxin binding to synaptosomes was unaffected by depolarization with elevated K+ concentrations, or by activation of the Na+ channels with batrachotoxin plus a purified polypeptide toxin from the scorpion Leiurus quinquestriatus. A procedure is described for preparing a membrane fraction that contains 70--80% of the total saxitoxin binding activity of the crude homogenate. The specific activity of this fraction was about 4 to 6 pmol/mg protein. About 60--70% of the saxitoxin binding sites were solubilized by incubating these membranes with the nonionic detergent Triton X-100; the detergent-solubilized binding sites eluted at a position corresponding to a mol wt of about 700,000 on gel filtration chromatography. Both membrane-bound and solubilized saxitoxin binding were assayed by a new cation exchange column method. The binding of saxitoxin to both membrane-bound and detergent-solubilized binding sites was saturable with an apparent dissociation constant of about 2 nM. Dissociation of the saxitoxin-receptor complex followed a single exponential decay with a rate constant at 0 degrees of 0.1 min-1 for membrane bound and 0.2 min-1 for detergent-solubilized binding sites. The measured association rate constant was 6 X 10(8) M-1 min-1 at 0 degrees for membrane-bound saxitoxin binding sites.


Intracellular chloride activities and active chloride absorption in the intestinal epithelium of the winter flounder.

Intracellular chloride activities, (Cl)c, and the electrical potential difference across the mucosal membrane, psimc, were determined in the isolated small intestine of the winter flounder, using Cl-selective and conventional (KCl-filled) microelectrodes. In the presence of a Na-containing buffer psimc averages -69 mV and (Cl)c averages 24 mM, a value that is 3.4 times that predicted for an equilibrium distribution across the mucosal membrane. On the other hand, when the tissue is then perfused with Na-free buffer, (Cl)c slowly falls to a value that does not differ significantly from that predicted for an equilibrium distribution, and psimc depolarizes significantly. Finally, when the tissue is again bathed in the Na-containing buffer, (Cl)c rapidly returns to a value well above equilibrium. These results, together with those of Frizzell et al. (J. Membrane Biol. 46:27, 1979), provide direct evidence that: (1) Cl is accumulated against its electrochemical potential difference (32 mV) by this tissue, and (2) this accumulation is coupled to and energized by the entry of Na down its steep electrochemical potential difference.


Highly purified basal lateral plasma membranes from rat duodenum. Physical criteria for purity.

Preparations of intestinal epithelial cell basal lateral plasma membranes were analyzed with free flow electrophoresis and density perturbation with digitonin. The initial basal lateral membrane preparations were obtained by equilibrium density gradient centrifugation after two different schemes of homogenization and differential sedimentation (A.K. Mircheff, C.H. van Os, and E.M. Wright. 1978. Membr. Biochem. 1:177, and A.K. Mircheff, S.D. Hanna, M.W. Walling, and E.M. Wright. 1979. Prep. Biochem. 9:33. In these preparations, Na,K-ATPase, a marker for the basal lateral mambrane, was purified 16- to 18-fold over the initial homogenate. The preparations were also enriched in NADPH-cytochrome c reductase, alkaline phosphatase, acid phosphatase, and galactosyltransferase. Both free-flow electrophoresis, which separates on the basis of surface charge, and density perturbation with digitonin, which depends on a specific interaction of digitonin with cholesterol-rich membranes, resolved the preparation into three populations of particles. The major population, which represented basal lateral membranes purified 20- to 32-fold with respect to the initial homogenate, contained Na,K-ATPase, alkaline phosphatase, adenylate cyclase, and acid phosphatase. A second population was defined by its content of NADPH-cytochrome c reductase, and the third was defined by its content of galactosyltransferase. Guanylate cyclase appeared to be partitioned between the Na,K-ATPase-rich and NADPH-cytochrome c reductase-rich populations. Galactosyltransferase is also present in fractions which contain the Na,K-ATPase-rich membranes, but the present data cannot exclude the possibility of spillover by the adjacent, galactosyltransferase-rich population. This work emphasizes the importance of multiple, physical criteria for purity in the isolation of subcellular components.


Effect of amiloride on the apical cell membrane cation channels of a sodium-absorbing, potassium-secreting renal epithelium.

The effect of the K-sparing diuretic amiloride was assessed electrophysiologically in the isolated cortical collecting tubule of the rabbit, a segment which absorbs Na and secretes K. Low concentrations of amiloride in the perfusate caused a rapid, reversible, decrease in the magnitude of the lumen negative transepithelial potential difference, Vte, transepithelial conductance Gte, and equivalent short-circuit current, Isc, with an apparent K1/2 of approximately 7 X 10(-8) M. The effects of a maximum inhibitory concentration of amiloride (10(-5) M) were identical to those observed upon Na removal from lumen and bath (Na removal from the bath alone has no effect). Removal of Na in the presence of 10(-5) M amiloride had no affect on Vte, Gte, or Isc, and is consistent with the view that amiloride blocks the Na conductive pathways of the apical cell membrane. Further, in the absence of Na, the subsequent addition of amiloride had no influence. In tubules where active Na absorption was either spontaneously low, or abolished by removal of Na from lumen and bath, the elevation of K from 5 to 155 meq/liter in the perfusate caused a marked change of the Vte in the negative direction and an increase in the Gte. These effects could be attributed to a high K permeability of the apical cell membrane and not of the tight junctions. Amiloride (10(-5) M) had no effect on these responses to K. It is concluded that amiloride selectively blocks the apical cell membrane Na channels but has no effect on the K conductive pathway(s). This selective nature of amiloride may indicate that Na and K are transported across the apical cell membrane via separate conductive pathways.


Reduction of stereotyped body-rocking using variable time reinforcement: practical and theoretical implications.

The first experiment assessed the effectiveness of two schedules of reinforcement in reducing stereotypy engaged in profoundly retarded patients in ward environments. These schedules were the differential reinforcement of other behaviour (DRO) and variable time reinforcement (VT). This experiment was terminated prematurely because of problems in implementing the DRO contingencies. However, the VT contingency appeared to reduce stereotypy. The second experiment evaluated the VT schedule of reinforcement alone. Significant decreases in amounts of stereotypy from baseline measures were observed in all five profoundly retarded female subjects. It is tentatively concluded that stereotypies in ward and laboratory environments differ in function. This has implications for the treatment of patients who engage in stereotyped behaviour.


Experimental hyperglycinaemia--an evaluation of the efficacy of strychnine therapy in nonketotic hyperglycinaemia.

A hyperglycinaemic state resembling the human disease nonketotic hyperglycinaemia (NKH) was created in male adult albino rabbits by injecting subcutaneously a ten  percent aqueous glycine solution. A single dose of 300 mg./kg. caused a transient rise of plasma glycine level, but CSF glycine concentration began to rise only after an injection of 1,000 mg./kg. glycine. Repetition of the latter dose every four hours for twenty-four hours caused a gradual rise of both plasma and CSF glycine. Progressive neurological symptoms, highly resembling the early stages of NKH, developed during this prolonged loading. Numerous therapeutic approaches have been made to NKH which, if not fatal during the neonatal period, leads to severe psychomotor retardation, but only strychnine treatment (100--200 micrograms./kg/. day) has resulted in some improvement of the clinical condition of these patients. However, even the highest tolerated dose of strychnine (1 mg./kg./day) did not significantly alter the progression of neurological symptoms during glycine loading in the present study. All but one of twenty-nine rabbits succumbed during glycine loading, and only three of twenty-one survived when the glucine-antagonist strychnine was administered during glycine loading. Therefore, it seems probable that the protective effect of strychnine in a hyperglycinaemic state is of limited value. Glycine loading influenced intermediate amino acid metabolism in several ways, plasma alpha-amino-N and ammonia level rose and moderate metabolic acidosis developed during the last phase of the experiment. Profound alterations of levels of amino acids involved in glycine metabolism occurred in both blood plasma and cerebropinal fluid.


The effects of institutionalisation on retardates social independence.

Subjects were grouped into eight experimental groups to control for mental age (MA) and chronological age (CA) and at the same time to allow the examination of the effects due to the proportion of lifetime spent institutionalised on an objective measure of social dependency. The results suggest that the longer proportion of life-time institutionalised, the more likely the retardate is to be socially dependent. The implications of this finding for retardates in institutional settings is discussed.


Post-maturation of the plastid ribosomal RNA in the plant kingdom.

The in vivo fragmentation of the plastid rRNA from plants situated at different places in the evolutionary sclae, with the exception of Algae, was analysed by electrophoresis using fully denaturing conditions. This fragmentation corresponds to an in vivo post-maturation. It exists only in some bacteria and is not random. Five main groups of fragments with the following real molecular weights (Mr) are found in 23 S: ca 0.9 x 10(6); 0.7 x 10(6); 0.45 x 10(6); 0.35 x 10(6) and 0.15 x 10(6). The existence of a large fragment (Mr = 0.9 x 10(6)) corresponds to a primitive type of fragmentation found in some archaic plants. Dicotyledons and several other groups have the same pattern of 23 S fragmentation, often comprising all the fragments mentioned above, whilst Graminaceae (Monocotyledons) constitute a special group with a very predominant 0.35 x 10(6) dalton fragment and the absence of the 0.45 x 10(6) dalton fragment. The plastid 16 S rRNA in all plants studied here has a Mr of 0.54 x 10(6) which is smaller than the 16 S of Escherichia coli taken as reference (0.56 x 10(6) dalton).


The role of metal ions in chemical evolution: polymerization of alanine and glycine in a cation-exchanged clay environment.

The effect of the exchangeable cation on the condensation of glycine and alanine was investigated using a series of homoinic bentonites. A cycling procedure of drying, warming and wetting was employed. Peptide bond formation was observed, and the effectiveness of metal ions to catalyze the condensation was Cu2+ greater than Ni2+ approximately Zn2+ greater than Na+. Glycine showed 6% of the monomer incorporated into oligomers with the largest detected being the pentamer. Alanine showed less peptide bond formation (a maximum of 2%) and only the dimer was observed.


Geometry of the dry-state oligomerization of 2',3'-cyclic phosphates.

Evaporation of a solution of thymidine plus either the exo or the endo diastereomer of uridine cyclic 2',3'-O, O-phosphorothioate (U greater than p(S) in 1,2-diaminoethane hydrochloride buffer gave the 2',5' and 3',5' isomers of (P-thio) uridylylthymidine (Up(S)dT) in a ratio of 1:2 with a combined yield of about 20%. These isomers were re-converted to U greater than p(S) and dT by a reaction that is known to proceed by an in-line mechanism. Both the 2',5' and 3',5' isomers gave as product the same diasteromer of U greater than p(S) that had been used originally in their formation. These dry-state 'prebiotic' reactions (Verlander, Lohrmann, and Orgel 1973) are thus shown to be stereospecific, and both the 2',5' and 3',5' internucleotide bonds are formed by an in-line mechanism.


Primary structure of pronghorn pancreatic ribonuclease: close relationship between giraffe and pronghorn.

Pancreatic ribonuclease from pronghorn (Antilocapra americana) was isolated and its amino acid sequence was determined from a tryptic digest of the performic acid-oxidized protein. Peptides were positioned by homology with other ribonucleases. Only peptides that differed in amino acid composition from the corresponding peptides of ox or goat ribonucleases were sequenced. In a most parsimonius tree of pancreatic ribonucleases, pronghorn and giraffe were placed together and these two were placed with the bovids, leaving the deer as a taxon separate from the other ruminants. The amino acid replacements that determine this tree topology are three rarely occurring replacements shared by pronghorn and giraffe. Notwithstanding their close phylogenetic relationship, both ribonucleases differ strongly in extent of glycosidation, net charge and antigenic properties.


The assessment of sexual function and marital interaction.

The increasing need expressed by clinicians and researchers alike for valid and reliable psychological measures of sexual behavior and adjustment contrast with the limited available information on the assessment of human sexual functioning. The aim of this article is to present relevant data on the psychometric characteristics of scales designed to measure one or more aspects of human sexual activity and marital interaction. This list is by no means exhaustive but covers most assessments of either individuals or dyads, mainly in a heterosexual context. Under the title of the scales, which have been arranged by alphabetical order according to the first author's name, the information provided may permit a preliminary judgment concerning the potential applicability of the instrument to the reader's need.


Assessing sexual behavior in couples.

The role of formal assessment in the practice of sex therapy with couples is discussed. A case is made for the use of behaviorally oriented paper-and-pencil tests of the self-report variety, in clinical settings, at two points in time: prior to any therapist-client contact and following completion of therapy. Such procedures are both efficient and effective, yielding information relevant to diagnosis, treatment planning, and development of clinical skills. Assessment procedures used routinely at the Stony Brook Sex Therapy Center are described and illustrated using sample cases. The authors suggest that behavioral assessment approaches have considerable clinical potential which has yet to be fully realized.


The DSFI: a multidimensional measure of sexual functioning.

The present report summarizes work to date on the Derogatis Sexual Functioning Inventory (DSFI), a multidimensional measure of human sexual functioning. We discuss the rationale for the test as well as the selection of the primary domains of measurement. Reliability coefficients for the various subtests are given, and a review section on validation studies is provided, including a factor analysis, predictive validation, and discriminant function analyses. Prototypic clinical profiles are also provided for several of the major types of sexual dysfunction.


The Sex Knowledge and Attitude Test (SKAT).

The Sex Knowledge and Attitude Test (SKAT) was designed to measure knowledge, attitudes and degree of experience in a variety of sexual behaviors, and to be used as a teaching and research instrument. The SKAT has been administered to over 35,000 students, approximately two-thirds of whom have been medical students. SKAT has served two major objectives: to measure changes in knowledge and attitudes after a course or program in human sexuality and to demonstrate the deficiencies of medical and nursing education in preparing health professionals to aid patients with sexual problems. Additional types of research using the SKAT are suggested.


The measurement of marital quality.

The quality of marital relationships is the most studied topic pertaining to marriage and family life. Moreover, clinicians have become increasingly interested in this variable as divorce rates have climbed and as services for counseling and therapy have become more readily available and more widely accepted. These research and clinical needs necessitate the availability of measures of variables which assess marital quality (e.g., marital adjustment, satisfaction, and happiness). This article discusses the need for such measures, reviews the history of measurements in this area, identifies some conceptual and methodological issues of relevance, and then focuses most specifically on the Dyadic Adjustment Scale developed by Spanier. Some cautions for clinicians are noted, and a discussion of future measurement needs is presented.


Partial hepatectomy reduces both metabolism and toxicity of benzene.

Removal of 70--80% of the liver reduced both the metabolism and the toxicity of benzene in rats. Metabolism was evaluated by measuring the levels of urinary metabolites in both sham-operated and partially hepatectomized rats given 2200 mg/kg [3H]benzene sc. Toxicity was evaluated by measuring the incorporation of 59Fe into circulating erythrocytes according to the method of Lee et al. The observation that partial hepatectomy decreases benzene metabolism and protects against benzene toxicity indicates that the liver may play a primary role in the development of benzene-induced bone marrow toxicity. The fact that benzene administration also reduces the ability of the liver to regenerate after partial hepatectomy suggests that the regenerating liver may serve as a model system in lieu of the bone marrow for studying the mechanism by which benzene inhibits cell proliferation.


A new in vitro method for testing plant metabolism in mutagenicity studies.

A rapid method was proposed to detect whether a harmless agricultural chemical can be converted into a mutagenic one by plant metabolism. The method is based on the use of Nicotiana alata cell cultures. Results obtained with five pesticides (atrazine, dichlorvos, tetrachlorvinphos, Kelevan, and maleic hydrazide) suggest that the proposed method simulates the metabolism of the whole plant. This procedure was also successfully applied to the genetic system of Aspergillus nidulans. One pesticide, atrazine, induced mutations and somatic segregation only after metabolism during cocultivation with N. alata cells.


Perinatal toxicity of maneb, ethylene thiourea, and ethylenebisisothiocyanate sulfide in rodents.

The potential of the fungicide maneb and two of  its metabolites, ethylenebisisothiocyanate sulfide (EBIS) and ethylene thiourea (ETU), to induce perinatal toxicity in four species of rodents was investigated. The compounds were admininistered to rats and mice during the period of organogenesis, and ETU was also administered to rats and mice during the period of organogenesis, and ETU was also administered by oral gavage for a similar period to hamsters and guinea pigs. Treatment also continued through the lactational period in groups of rats that were allowed to give birth. Fetuses were examined for signs of toxicity, including terata, and neonates for reflex developement and open-field behavior. Maneb produced hydrocephalus in fetuses in litters of rats receiving 480 mg/kg . d. No fetotoxic effects were noted in litters of rats receiving EBIS at doses at high as 30 mg/kg . d. ETU proved to be a potent teratogen in the rat. Among the effects seen at doses of 40 mg/kg . d or greater were hydrocephalus, encephalocele, kyphosis, and various defects of the digits. Neither maneb (up to 1500 mg/kg . d), ETU (up to 200 mg/kg . d), nor EBIS (up to 200 mg/kg . d) elicited signs of fetal toxicity in the mouse. ETU also failed to result in fetal toxicity when administered to the hamster (100 mg/kg . d) or the guinea pig (100 mg/kg . d). Neither maneb nor EBIS produced significant dose-related alterations in the behavioral development of perinatally exposed rat neonates. At doses that also produced neonatal hydrocephalus, ETU produced significant increases in the open-field activity of the neonates. In addition to the perinatal effects noted above, both maneb and EBIS caused maternal limb paralysis in the rat, an effect not noted in the mouse at much higher doses.


Embryotoxic and teratogenic effects of petroleum hydrocarbons in mallards (Anas platyrhynchos).

Egg surface applications of microliter quantities of crude and refined oils of high aromatic content are embryotoxic to mallards (Anas platyrhynchos) and other avian species; applications of aliphatic hydrocarbons have virtually no effect. Mallard eggs at 72 h of development were exposed to a mixture of aromatic hydrocarbons or to aromatic compounds representative to those present in crude oil to assess their toxicity. The class composition of the mixture was similar to that of South Louisiana crude oil, an American Petroleum Institute reference oil. Application of 20 microliter of the mixture reduced embryonic survival by nearly 70%. The temporal pattern of embryonic death was similar to that after exposure to South Louisiana crude oil. Embryonic growth was stunted, as reflected by weight, crown-rump length, and bill length, and there was a significant increase in the incidence of abnormal survivors. When individual classes of aromatic hydrocarbons were tested, tetracyclics caused some embryonic death at the concentrations in the mixture. When classes were tested in all possible combinations of two, no combination appeared to be as toxic as the entire mixture. Addition of the tetracyclic compound chrysene to the aromatic mixture considerably enhanced embryotoxicity, but could not completely account for the toxicity of the crude oil. The presence of additional unidentified polycyclic aromatic hydrocarbons as well as methylated derivatives of polycyclic aromatic compounds such as chrysene may further account for the embryotoxicity of the crude oil.


Accumulation and excretion of [1-14C]bis(tri-n-butyltin) oxide in mice.

Laboratory COBS strain albino mice were administered [1-14C]bis(tri-n-butyltin) oxide in dilute aqueous solutions. Test solutions were prepared by using an elastomeric controlled-release formulations that emitted the agent at a constant rate. Tissue and excreta were periodically analyzed for 14C by standard liquid scintillation counting methods. Assuming that the label was not cleaved from the tin, 90--96% of the ingested agent was excreted, predominantly in the feces. Of the remainder, kidney levels were high, possibly indicating metabolism; tissue accumulation was diffuse, with liver, spleen, and fat predominating. Blood levels were low. Termination of organotin ingestion led to rapid clearance of storage sites.


Variation of corneal glycosaminoglycan values of hares in relation to environmental pollution by industrial emissions.

In localities contaminated by industrial emissions a significant decrease in keratan sulfate and chondroitin 4-sulfate occurs in the cornea of the hare. The changes also occur in hares living near small emission sources with a local emission zone; therefore they should not be neglected, especially if the area is used for recreation, as in the case reported here. The decrease in glycosaminoglycan values is more pronounced in adults than in juveniles, because of the length of exposure. Relatively large amounts of keratan sulfate in the glycosaminoglycan fraction correspond to changes expected in a prematurely senescent tissue. Because of the painstaking laboratory work required, assessment of glycosaminoglycans could be used for special bioindication purposes but would not be suitable for routine monitoring.


Nickel(II)-binding constituents of human blood serum.

Studies were undertaken to investigate the Ni(II)-binding properties of human blood serum and to identify the low-molecular-weight Ni(II)-binding constitutents in the serum. Three Ni(II)-binding fractions were obtained when labeled nickel chloride (63NiCl2) was added to the native serum. Of the total Ni(II), 95.7% was associated with albumin, 4.2% was bound to low-molecular-weight components, and a small fraction, usually less than 0.1% was associated with a high-molecular-weight protein that was eluted in the void volume of Sephadex G-150. Amino acids were shown to be responsible for the low-molecular-weight Ni(II)-binding fraction and L-histidine was found to be the main (Ni(II)-binding amino acid in human blood serum. Compared with albumin, L-histidine was shown to possess a greater affinity for Ni(II). Ni(II)-binding to human albumin became evident only when no more L-histidine was available. Since the concentration of albumin is much higher than the concentration of L-histidine in normal serum, most of the added Ni(II) was associated with albumin. The equilibria between Ni(II)-L-histidine and Ni(II)-albumin may facilitate the transport of Ni(ii) between blood and tissues.


Inorganic mercury(II)-binding components in normal human blood serum.

The interaction of Hg(II) with human blood serum was studied at physiological pH. Most of the Hg(II) was found to be associated with the proteins, and only a small fraction was associated with the low-molecular-weight substances in serum. Albumin is the major Hg(II)-binding protein (greater than or equal to 90%) in serum. Among the amino acids, L-cysteine has the highest affinity for Hg(II). In dialyzed serum having equimolar concentrations of Hg(II), albumin, and L-cysteine, the amount of Hg(II) found in the supernatant after ultracentrifugation was about 6--7%. There are preferential Hg(II)-binding sites on the albumin molecule. However, no significant change in the circular dichroism spectrum of albumin was detected until at least two equivalents of Hg(II) were present. Hg(II) can mediate the formation of the albumin dimer as well as a ternary complex of the type albumin-Hg(II)-L-cysteine. The latter presumably plays an important role in the transport of Hg(II) between blood and various tissues.


Proliferation of lung and airway cells induced by nitrogen dioxide.

Proliferation of lung cells of Chinese hamsters was examined in several regions of the lung parenchyma and ciliated airway epithelium after a 24-h exposure to 28.2 mg/m3 (15 ppm) nitrogen dioxide (NO2). Label was retained 3 wk after the injection of [3H]thymidine, and autoradiographic methods were used to localize the site of retention. By 24 h after administration of [3H]thymidine, parenchymal areas, exclusive of airways, showed an increased labeling index, indicative of cell death and replacement. This increase in the number of labeled cells persisted for 3 wk. Type II cells were labeled twice as frequently in regions of the terminal bronchiole than in other alveolar areas. Type II cell cycle time was reduced from 26 to 3 d after NO2 exposure. Alveolar macrophages were significantly labeled in the alveolar areas during the thymidine pulse at the end of the exposure episode and retained label for 3 wk. Airway epithelia showed no labeling in the trachea and progressively greater labeling in increasingly small er airways. Epithelial cells lining the small airways and alveoli showed greater susceptibility to NO2 injury than cells lining the bronchi or trachea. Nonciliated or basal cells serve as a precursor of ciliated cells in the epithelium of small airways (0.35 mm) and bronchi.


Effect of styrene and fiber glass on small airways of mice.

Three groups of 20 mice each were exposed to respirable glass fibers, to 300 ppm styrene vapor, and to glass fibers plus 300 ppm styrene. The glass fiber concentration was congruent to 1070/cm3; fiber diameters were under 3 micron and fiber lenths under 10 microns. The 5 h/d, 5 d/wk inhalation experiment lasted 6 wk. Glass fibers did not cause any lung damage when inhaled separately but combined styrene and glass fibers induced a change in the cellularity of the bronchiolar lining, where aprocrine-type cells became predominant. The same type of bronchiolar epithelial change was found in 10% of the styrene-exposed mice, while most of the styrene-exposed animals (90%) presented thickened bronchiolar walls becasue of stratification of the bronchiolar epithelium.


Residue studies with [14C]fosamine ammonium in channel catfish.

The active ingredient in du Pont Krenite brush control agent is ammonium ethyl carbamoylphosphonate (fosamine ammonium salt, formerly known as DPX-1108). Residues in channel catfish exposed to 1.1 ppm 14C-carbonyl-labeled fosamine ammonium in water for 4 wk were found to plateau in 2-3 wk with an accumulation factor (ratio of residue in fish to residue in water) of less than 1. In a separate experiment channel catfish were placed for 4 wk in a tank containing [14C]fosamine ammonium-treated soil (15 ppm) that had been aged for 30 d prior to flooding and initiation of fish exposure. The residue levels in this latter group of catfish also plateaued in 2-3 wk with an accumulation factor of less than 1. In both experiments, after the 4-wk exposures, the fish were transferred to fresh water for 2-wk depuration periods, during which residue levels dropped 50--90%. No effects on the fish were observed during these experiments.


In vitro formation of neuroglial synapses.

Neuroglial synapses have been systematically observed in histotypical cerebellar rotary tissue cultures. These axoglial contacts appear as excitatory-like synapses in which the presynaptic element contains rounded synaptic vesicles accumulated at the presynaptic active zone. The post-synaptic structures were always the somata as well as processes of astrocytic glial cells. The axoglial contacts appear in these cultures when they are prepared from 16-day-old chick embryos cerebellum and cultivated during 6 days. To explain these neuroglial interrelationship it has been suggested as a working hypothesis that glial and nerve cells develop plastic capacities in order to establish synaptic contact in the in vitro conditions.


Uptake of 2-deoxy-D-glucose by cortical synaptosomes from the Long-Evans rat.

Uptake of 2-deoxy-D-glucose (2-DG) has been studied in synaptosomes from the Long-Evans rat. Although there are some differences, the results are generally similar to those reported for Sprague--Dawley rats. Both D-glucose and 2-DG are taken up by the same carrier, since D-glucose was found to inhibit uptake of 2-DG. Uptake is highly dependent on a source of metabolic energy, since incubation at 0 degrees C completely eliminated uptake, while 10(-3) M 2,4-dinitrophenol (DNP) inhibited uptake by 76.5%. Uptake has also been measured as a function of both 2-DG and sodium concentration and the data fitted to a model. Sodium is found to inhibit uptake. A model assuming noncompetitive inhibition by sodium gives best fit to the data. Thus both Kt and apparent Vm are dependent on the sodium concentration. Although these effects are small, Kt increases with [Na], while apparent Vm declines.


Cerebral uptake of nicotine and of amino acids.

Nicotine is among the compounds that enter the brain very rapidly (blood-flow-limited). It also leaves the brain rapidly; by five minutes, 90% exits, an exit somewhat slower than that of water. In spite of rapid exit, brain levels remain higher than levels in blood over a wide range of blood concentrations. Nicotine enters the fetal circulation from the maternal blood; it enters fetal brain but to a smaller extent than adult brain. Nicotine entry is different from that of amino acid: No interaction of amino acid transport and nicotine could be detected. Most close analogs have no effect on nicotine uptake, but at higher concentrations nicotine uptake is saturable. Nicotine and morphine mutually inhibit each other's uptake. The results suggest an uptake compartment (lipid space) for nicotine shared by morphine.


The effect of morphine tolerance on the incorporation of 3H-leucine into proteins of rat synaptic membranes.

The rate of incorporation of 3H-leucine into proteins of the synaptic junctional and nonjunctional membranes and synaptic vesicles of rat brain has been examined in control and morphine-tolerant rats. There are no discernible differences between control and tolerant animals in amount of protein as measured by densitometric tracings of dye-stained proteins separated by acrylamide gel electrophoresis from the three membrane fractions of whole brain areas. However, there are differences in the turnover of membrane protein: three vesicle protein bands and one junctional-membrane protein band are significantly more highly labeled, and one junctional-membrane protein is significantly less highly labeled by 3H-leucine in samples from tolerant rats. Of these, the two junctional-membrane proteins can be tentatively identified as components of the post synaptic densities, and one of the vesicle proteins as tubulin.


Pediatric pelvic fractures: review of 52 patients.

Fifty-two patients (ages 1 to 16 years) with pelvic fractures were hospitalized at an urban medical center during a 5-year period. All patients with acetabular fractures had adjacent hemipelvis fractures. None were seen to develop symptomatic acetabular dysplasia. Stable breaks in the ring (anterior ring fracture) were encountered most frequently. While many patients were discharged ambulating within a short time, over 50% had prolonged hospitalizations due to associated truma. Only one child had serious urologic trauma, demonstrating that isolated anterior ring fractures in children are not as treacherous in terms of pelvic content injury as those one might encounter in adults. Unstable breaks (anterior and posterior ring fractures) pose acute and chronic management problems and associated injuries are often fatal. Life-threatening complications may overshadow proper fracture management. It is critical to maintain a symmetrical pelvis in order to prevent either cephalad translation or anterior-posterior hemipelvis rotation. A child with the latter problem is presented in detail.


Filtration of debris from banked blood.

Commercially available filters will effectively remove microaggregates from stored blood. The combined results of screen filtration pressure (SFP), debris weight, and particle size analysis offer a reproducible means of evaluating different filters. The effectiveness of three blood filters (Fenwal, Bentley, and Pall) is evaluated using SFP, debris weight measurement, particle size analysis, and determinations of filter capacity. Of the filters studied the Fenwal filter provides the most efficient means of removing debris while maintaining adquate flow rates for relatively large volumes of blood. The filter appears comparable to the Swank filter in overall effectiveness and flow characteristics.


Adenylate cyclase after burn injury: resistance to desensitization by catecholamines.

In vivo injection of isoproterenol(IPR) (4 mg/kg) in normal rats caused fat cell adenylate cyclase to become desensitized to stimulation by IPR in vitro. In contrast, adenylate cyclase from tissues of burn-injured rats (20% body surface, full-thickness scald) remained fully responsive to stimulation by IPR for several days after injury even though catecholamine excretion was elevated more than twofold. Furthermore, fat cell adenylate cyclase from burn-injured animals was not desensitized after acute in vivo IPR injections, whereas adenylate cyclase from the shams did become desensitized after acute IPR injections. To determine whether the apparent resistance to desensitization in burn-injured rats might be an adaptation to the chronic elevation of catecholamines that follows burn injury, two other rat models in which catecholamines are chronically elevated were studied: one was produced by a twice daily schedule or IPR (1 mg/kg) injections for 3 weeks; the other by 3 weeks' cold exposure (0--4 degrees C). As had been observed in burn injury, adenylate cyclase remained fully responsive to IPR in both models, and adenylate cyclase from the cold-acclimated rats was resistant to desensitization by acute injections of IPR. It therefore seems likely that chronic elevations of catecholamines evoke regulatory mechanisms in target cells to circumvent the desensitizationwhich would otherwise occur consequent to acute exposures to catecholamines. In burn injury this  may result in an inadvertent adaptation which contributes to hypermetabolism.


Effects of reserpine upon thermal stress-induced cardiovascular changes.

The cardiovascular changes induced by 15% total body surface area third-degree burn have been studied in anesthetized dogs. The responses observed were a decrease in plasma volume, a decrease in cardiac output, and a slight but insignificant fall in mean arterial pressure. Graded doses of reserpine ranging from 0.1 to 1.0 mg/kg were administered preceding thermal trauma, and produced a reduction in plasma volume loss. The most effective dose of reserpine was 0.2 mg/kg. Despite the significant reduction (approximately 50%) of plasma volume loss in this dosage group, there were no significant alterations in either cardiac output or mean arterial pressure. These results demonstrate that reserpine is effective in reducing plasma volume loss but ineffective in altering the other cardiovascular parameters observed. Based upon the size of the maximally effective dose in reducing plasma volume loss and the failure of this dose to alter the other cardiovascular responses, it is postulated that the plasma loss reduction may be due to some action of reserpine other than its release of catecholamines and reduction in catecholamine stores.


Clinical implications of blood gas analysis of chest tube drainage.

Blood gas analysis of chest tube drainage following thoracostomy for experimental and clinical penetrating chest injuries was evaluated to determine its usefulness in predicting the etiology of the injury. Twenty dogs were divided into four groups and sustained right chest injury as follows: Group I--closed chest lung laceration; Group II--open chest lung laceration; Group IIII-gunshot wounds; Group IV--thoracotomy and injection of autologous, mixed venous blood. All animals and 14 patients who sustained penetrating chest injury were made simultaneously from chest tube draininage, systemic artery, and central vein in all dogs and patients. Eight patients (Group A) had pneumothorax; six patients (Group B) did not. Mean control canine aortic PO2 and pulmonary arterial PO2 values in Group I did not differ significantly from those in the other three canine groups, nor from the two human groups. Group II dogs exhibited chest tube PO2 which was significantly (p less than 0.01) above aortic PO2. In Group IV, chest tube PO2 was increased significantly above pulmonary arterial blood. Patients without pneumothorax had values for PO2 in chest tube drainage and aorta which were not significantly different, whereas when pneumothorax was present, PO2 of chest tube drainage was significantly higher than that of aortic PO2. Thus blood gas determinations on chest tube drainage may reflect the nature of the injury; however, the presence of air in the pleural space can result in oxygenation of contained blood well above systemic arterial levels.


Injury patterns in motorcycle accidents.

A retrospective study of 260 cases of motorcycle accidents which occurred over a 4 1/2 year period is reported. Approximately 8% died of their injuries. The vulnerability of the tibia to open fractures is noted, and the frequent association of these open injuries with severe contamination and devitalization of tissues resulting in a high complication rate. Severely comminuted intraarticular fractures of the distal tibia and radius were numerous, and one is tempted to name the injury the "motorcycle radius." Traumatic amputations were few and all involved the lower extremity. Fractures of the cervical and thoracic spine numbered only one each, but in each instance severe neurologic sequelae ensued. A plea is made for more accident prevention measures including protective equipment and driver education specific for the motorcyclist.


Complete sensorimotor paralysis after cord injury: mortality, recovery, and therapeutic implications.

In 273 completely paralyzed cord injured patients, the 1-year mortality was 34% in the patients with cervical fractures and 7% in the patients with thoracic and thoracolumbar fractures. Recovery of useful motor function return occurred in 6.7% of the cervical and 11% of the thoracic and thoracolumbar patients; only 1% of the patient population became completely normal. No specific treatment could be singled out as aiding recovery. A case with recovery from complete paralysis after C5--6 fracture-dislocation is presented.


Ayptical lumbar spine injury from a two-point seatbelt.

A case of atypical lumbar spine injury of a 20-year-old man is described. Injury resulted from a car crash while the man was wearing a two-point safety belt. The characteristics of injuries caused by seatbelts are described. In previous cases displacement fractures were usually at the same level. The patient reported is unusual in that a longitudinal fracture of L3 and injury at two different levels occurred. Recovery was uneventful.


Fractures of the calcaneum.

Sixty-seven patients with 86 fractures of the calcaneum were re-examined 2 to 6 years after their injury. These fractures of the calcaneum were of two types: thalamic, involving the posterior subtalar joint (85%); and nonthalamic, confined to the extra-articular area (15%). Treatment had been by functional therapy, plaster fixation, pin reduction, or open reduction. At followup, only 28 of the 86 heels were entirely painless. Pain was most common posterolaterally along the peroneal tendons; reduction of the tuber (Böhler) angle correlated significantly (p less than 0.001) with an abutment of the peroneal tendons. Motion in the subtalar joint was restricted in two thirds of the series, and in the talocrural joint in one third; a reduction of the tuber angle correlated significantly (p less than 0.001) with reduced mobility of these joints. The duration of sick leave was significantly (p less than 0.05) shorter after functional treatment of displaced thalamic fractures than after treatment with pin reduction and immobilization in plaster. Results were the same with both modes of treatment. The results of treatment of nonthalamic fractures were rewarding, whereas a common consequence of thalamic fractures was considerable impairment of ankle function. The significant correlation between a depressed tuber angle and unsatisfactory functional results suggests that closer attention should be paid to the accurate alignment of the posterior subtalar joint in the treatment of thalamic fractures of the calcaneum.


Therapeutic arterial embolization in trauma.

Use of therapeutic arterial embolization (TAE) in the traumatized patient can achieve rapid control of hemorrhage and obviate the need for immediate surgery on poor-risk patients or in high-risk areas of the body. The techniques of embolization, its risks, and complications are discussed in light of the authors' experience, and a review of recent literature is presented.


Acute effect of open joint wounds on articular cartilage and synovium in rabbits.

Open joint wounds were made in immature and mature rabbit knees by surgical arthrotomy. The wounds of the right knees were packed open for 5 days and the left knee wounds were closed primarily. The biochemical studies were selected to determine the effect of our treatment regimen on changes in the metabolism of articular cartilage and synovium. Neither closed nor open treatment produced significant changes in enzyme activities measured in the articular cartilage as compared to the controls in either immature or mature rabbits. Most of the synovial enzymes were elevated in the injured joints. There were, however, no significant differences in enzyme activity between the joints treated by either open or closed methods. Our findings suggest that short-term open treatment wounds does not cause matrix degradation in the cartilage nor affect the synovium more than simple arthrotomy.


Undiagnosed deep ulnar nerve paralysis resulting from stab wounds of the palm.

Stab wounds of the palm may cause laceration of the ulnar deep motor nerve. The acute diagnosis can be very difficult, since had sensation and major tendon function are uninvolved. Three cases are presented with ulnar deep motor paralysis secondary to stab wounds of the palm undiagnosed at the time of injury. The early diagnosis with nerve repair should yield excellent results and prevent permanent paralytic deformity.


Primary treatment of shotgun injuries to the face.

The treatment of close-range shotgun wounds to the face can be extremely difficult. Over the years, surgeons have progressed from the conservative approach of debridement and delayed reconstruction to that of immediate reconstruction. While the complex nature of these injuries requires treatment on an individual basis, the principles of conservative debridement, thorough wound cleansing, and primary replacement of soft-tissue defects will often result in a better functional and esthetic restoration in a shorter period of time. Five patients with shotgun facial wounds managed by individualized primary repair are discussed.


Brainstem evoked potentials to tonepips in notched noise.

Notched noise can be used to mask the frequency spread of acoustic energy in the brief tonepips that are used to elicit brainstem evoked potentials. Brainstem responses to tonepips and notched noise can therefore be used to evaluate auditory thresholds at particular frequencies. These thresholds are more frequency-specific than those obtained using tonepips alone, and are accurate to within 20 dB of the conventional audiometric thresholds.


Blepharoplasty: when to combine it with brow, temple, or coronal lift.

Some patients coming for esthetic blepharoplasty should have one of three supplemental procedures performed to elevate or change the position of the eyebrows. The most precise eyebrow alterations are effected with brow lifting procedures, but these may produce adverse scarring. The temple lift may be employed to draw the lateral part of the eyebrow upward and laterally. Drooping of the central part of the eyebrow requires a frontal or coronal lift or an eyebrow lift. Additional guides to the selection and combination of the procedures are provided.


Antral-choanal polyps.

The series involves 38 patients who had antral-choanal polyps removed at the Mayo Clinic during the 10 year period between 1965 and 1974. In contrast to common nasal polyps, antral-choanal polyps often are solitary and unilateral and usually are not associated with an allergic diathesis. These polyps recur frequently if they are simply avulsed; permanent ablation of the polyps requires thorough curettage of the antrum.


The effectiveness of hearing protectors in practice.

A series of workmen being evaluated for pensions for occupational hearing loss were asked to bring their own hearing protectors from work, to fit them themselves, following which attenuation studies were made. The muffs and most earplugs produced similar attenuation levels at high frequencies, although the muffs produced less attenuation at low frequencies. In all cases the mean attenuation was significantly lower than optimum figures suggested in the literature, and the standard deviation was relatively high. Personally molded earplugs were significantly less effective than other plugs used. Reasons are discussed for the relatively poor performance of these devices and the concept of assumed protection, i.e. mean minus one standard deviation, is discussed. There is need for better instruction on how to use hearing protectors if they are to be effective.


Cross-links in African swine fever virus DNA.

African swine fever virus DNA sediments in neutral sucrose density gradients as a single component with a sedimentation coefficient of 60S. In alkaline sucrose density gradients, this material shows two components with sedimentation coefficients of 85S and 95S, respectively. The sedimentation rate value of alkali-denatured virus DNA in neutral sucrose density gradients and the renaturation velocity of denatured DNA show that is reassociated much faster than expected from its genetic complexity. This behavior is compatible with the existence of interstrand cross-links in the molecule. We also present results which suggest that there are only a few such cross-links per molecule, that they are sensitive to S1 nuclease digestion, and that they are probably located next to the ends of the DNA.


In vitro translation products specified by the transforming region of adenovirus type 2.

Region 1 DNA sequences (map positions 0 to 11% on the linear adenovirus 2 genome) are expressed both early and late in lytic infection and are required for transformation by the virus. During productive infection six distinct cytoplasmic RNAs are synthesized from this region. These RNAs comprise two families, each consisting of three size classes that share 3' sequences. Region 1 RNA's were purified by hybridization selection, using restriction fragments bound to nitrocellulose membranes, and by size fractionation. The isolated RNAs were then translated in cell-free systems derived from wheat germ and rabbit reticulocytes. The family of RNAs specified by 0 to 4.4 sequences includes two RNAs, which are 12S and 13S in size. These RNAs were partially separated by molecular weight and translated. The 13S RNA produced 53,000-dalton (53K) and 41K peptides, and the 12S RNA synthesized 47K and 35K products. The family of RNAs mapping from 4.4 to 11.0 encodes three separate polypeptides, each of which can be assigned to a specific RNA. A 12K product that comigrates with structural polypeptide IX is synthesized from the 9S RNA as previously reported (U. Pettersson and M. B. Mathews, Cell 12:741-750, 1977). The 13S RNA encodes a 15K polypeptide that corresponds to a 15K polypeptide in infected cell extracts. The 22s RNA encodes a 52K protein distinct from the 0 to 4.4 polypeptides.


Measles virus-specified polypeptide synthesis in two persistently infected HeLa cell lines.

Measles virus-directed protein synthesis was examined in two HeLa cell lines (K11 and K11A) that are persistently infected with wild-type measles virus. Four viral proteins (H, hemagglutination protein; P, nucleocapsid-associated protein; NP, the major nucleocapsid protein; and M, the matrix protein) were readily detected in both cell lines by immune precipitation of [(35)S]methionine-labeled cell extracts followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. When analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, three (H, NP, and M) of the four viral proteins in both K11 and K11A cells differed from the corresponding viral proteins synthesized in HeLa cells acutely infected with the parental wild-type virus. In addition, the M protein from K11A cells migrated significantly more slowly on sodium dodecyl sulfate-polyacrylamide gel electrophoresis than the M protein from K11 cells, and there appeared to be slight differences in the H and NP proteins between these two persistently infected cell lines. The altered viral proteins detected in K11 and K11A cells appeared to be the result of viral mutations rather than changes in the host cell, since virus recovered from these cells directed the synthesis of similar aberrant viral proteins in HeLa cells. Virus recovered from K11 cells and virus recovered from K11A cells were both temperature sensitive and grew more slowly than wild-type virus. HeLa cells infected with virus recovered from K11 cells readily became persistently infected, resembling the original persistently infected K11 cells. Thus, viral mutations are associated with persistent measles virus infections in cell cultures.


Genome complexities of the three mRNA species of snowshoe hare bunyavirus and in vitro translation of S mRNA to viral N polypeptide.

The genome complexities of the principal intracellular viral complementary RNA species of the snowshoe hare bunyavirus have been analyzed by duplex analyses involving hybridization of complementary RNA to individual 32P-labeled viral RNA species (large, L; medium, M; and small, S), recovery of nuclease-resistant duplexes, and determination of the oligonucleotide fingerprints of the protected 32P-labeled viral sequences. The result for the M RNA (which codes for the glycoproteins G1 and G2; J. R. Gentsch and D. H. L. Bishop, J. Virol. 30:767-770, 1979) indicates that there is a single polycistronic M mRNA. Similar results were obtained for the L and S RNA species. In vitro translation studies with the S complementary RNA species of snowshoe hare virus as well as melted purified S duplexes substantiate earlier genetic and molecular studies (J. R. Gentsch and D. H. L. Bishop, J. Virol. 28:417-419, 1978; J. Gentsch, D. H. L. Bishop, and J. F. Obijeski, J. Gen. Virol. 34-257-268, 1977), which indicate that S mRNA codes for the virion nucleocapsid protein N.


Recombination between snowhoe hare and La Crosse bunyaviruses.

We have previously reported heterologous genetic recombination resulting from crosses involving temperature-sensitive (ts) mutants of La Crosse (LAC) group II and snowshoe hare (SSH) group I ts mutants (J. Gentsch, L. R. Wynne, J. P. Clewley, R. E. Shope, and D. H. L. Bishop, J. Virol. 24:893-902, 1977). From those crosses two reassortant viruses having the large/medium/small viral RNA segment genotypes of SSH/LAC/SSH and SSH/LAC/LAC were obtained. In this study it has been found that the reciprocal cross (SSH group II x LAC group I ts mutants) has not yielded the expected LAC/SSH/SSH or LAC/SSH/LAC reassortant viruses. The backcross of a SSH/LAC/SSH group II ts mutant with a LAC group I ts mutant has produced a new reassortant virus, LAC/LAC/SSH, whereas the backcross of SSH/LAC/LAC group I ts mutants with SSH group II ts mutants gave another reassortant, SSH/SSH/LAC. Backcross analyses of LAC/LAC/SSH group I ts mutants with Group II ts mutants of SSH have not yielded the expected LAC/SSH/SSH reassortant virus, nor have backcrosses of SSH/SSH/LAC group II ts mutants with group I ts mutants of LAC virus yielded the expected LAC/SSH/LAC reassortant. Possible reasons why certain reassortant viruses are not produced are discussed. A procedure to screen SSH-LAC reassortant viruses which differ in their virion N polypeptides is described.


Species specificity of interferon action: maintenance and establishment of the antiviral state in the presence of a heterospecific nucleus.

The expression of the interferon-induced antiviral state was studied in heterokaryons and cytoplasmic hybrids (cybrids). An autoradiographic assay for the antiviral state, in which the percentage of cells containing vaccinia viral DNA factories was determined, was used. The expression of the antiviral state was dominant in homokaryons and heterokaryons formed by fusion of interferon-treated cells with untreated cells. Cytoplasts derived from treated cells conferred resistance to virus growth on cybrids formed by fusing such cytoplasts with untreated cells. Treatment of L cell x HeLa cell heterokaryons with human interferon or mouse interferon was much less effective in inducing a detectable antiviral state than was similar treatment of parental cells with homospecific interferon. The antiviral state was fully induced when heterokaryons were treated simultaneously with both types of interferon. Cybrids formed by fusing L cell cytoplasts with HeLa cells or HeLa cytoplasts with L cells did not enter a detectable antiviral state after treatment with interferon specific for the cell type of the enucleated parent. However, treatment of cybrids with interferon specific for the cell type of the nucleated parent was effective in inducing a detectable antiviral state.


Adenovirus type 2 terminal protein: purification and comparison of tryptic peptides with known adenovirus-coded proteins.

The protein covalently bound to the 5' termini of adenovirus type 2 DNA has been purified from virus labeled with [35S]methionine, using exclusion chromatography of disrupted virions to isolate the DNA-protein complex, which is then digested with DNase. The terminal protein isolated from mature virus is most effectively labeled if the cells are exposed to [35S]methionine during the "intermediate" period of 13 to 21 h postinfection, suggesting that the protein is synthesized during this interval. The tryptic peptides of the terminal protein were compared with those of several known adenovirus-coded proteins and found to be unrelated. In particular, the terminal protein is not related to the 38-50K early proteins encoded by the leftmost 4.4% of the adenovirus genome, one region essential for the transforming activity of the virus. Neither is it related to the 72K single-strand-specific DNA binding protein, the minor virion component IVa2, or the major capsid component hexon.


Abortive transcription products of vaccinia virus are guanylylated, methylated, and polyadenylylated.

Abortive transcription products were synthesized in vitro by UV-irradiated vaccinia virus particles that were incubated with all four ribonucleoside triphosphates or by unirradiated particles that were incubated in reaction mixtures deficient in CTP or UTP. The RNA sedimented at 4 to 6S in sucrose gradients, suggesting that premature termination had occurred, presumably in one case because the DNA contained UV-induced pyrimidine dimers and in the other case because of ribonucleoside triphosphate was present at limiting concentration for transcription. Nevertheless, the short transcripts were capped, methylated, and polyadenylylated, indicating that neither completion of an RNA chain nor processing from a polycistronic precursor was required for modification of either end of the RNA. In addition, the finding of m7G(5')pppAm and m7G(5')pppGm at the 5' ends of the short RNA molecules implied that transcription was initiated with both ATP and GTP. The presence of the polyadenylic acid tract suggested that a slow-down or cessation of transcription, rather than a specific 3'-terminal sequence, served as a signal for polyadenylylation.


Efficient propagation of measles virus in suspension cultures.

Suspension cultures of a human prostate cell line (MA160) supported abundant growth of the Edmonston strain of measles virus. The virus yields obtained with these suspension cultures (150 to 800 PFU/cell) were at least 20- to 100-fold higher than those frequently reported in the literature. Monolayer cultures of MA160 cells did not support a virus replication nearly as efficiently (progeny yield, 25 PFU/cell).