Medical examination of torture victims applying for refugee status.

Torture is being increasingly reported. Canada provides a refuge for some of the victims. The medical evidence may be sufficient to give an applicant refugee status. Protocols are presented for the use of physicians in examining applicants for refugee status, and a series of cases is reported in which these protocols were followed.


[Renal and perinephritic abscesses in children].

One child with a pure perinephric abscess and three with renal abscesses, one of which had perinephric extension, are described. All presented with a long course of subacute infection leading to localizing symptoms or signs in the flank. The diagnosis was confirmed by radiologic examination. All the abscesses were surgically drained at various intervals after diagnosis, while the patients were receiving antibiotic therapy. Salvage of renal function was possible in all cases. A rational approach to the diagnosis and management of such abscesses is emphasized.


Successful management of quadruplet pregnancy in a perinatal unit.

A case of quadruplet pregnancy is outlined and the management is described to demonstrate the application of monitoring and therapeutic procedures currently available for a multifetal pregnancy. Recording of the nonstressed fetal heart rate, ultrasound monitoring and glucocorticoid stimulation of pulmonary biochemical maturity were done. A successful outcome was achieved with a combined obstetric-neonatal approach and the experience of a perinatal unit.


A review of Providencia bacteremia in a general hospital, with a comment on patterns of antimicrobial sensitivity and use.

Six cases of Providencia bacteremia occurring between 1969 and 1978 were reviewed. These cases represented 3% of the gram-negative bacteremias occurring at one hospital. All six cases of Providencia bacteremia were secondary to urinary tract infection with P. stuartii, and in most the infection developed only shortly before the onset of bacteremia; in three cases the bacteremia developed immediately following manipulation of the urinary tract. Patients with long-standing Providencia infections did not acquire bacteremia. The signs and symptoms of Providencia bacteremia were typical of those of septicemia except that vascular collapse was not a prominent feature, occurring in only one patient. The mortality was 33%. All the Providencia strains cultured from the bloodstream were susceptible to gentamicin, although the frequency of gentamicin resistance increased from roughly 10% to 50% during the period studied; the increase in gentamicin use over this period was more gradual. Also noted was a decrease in resistance to ampicillin that paralleled a decrease in ampicillin use. All the Providencia strains were susceptible to amikacin.


Epidemic of mumps in a partially immune population.

The incidence of mumps in vaccinated and nonvaccinated schoolchildren was studied after a recent epidemic. Information was collected by telephone interviews with the parents and a review of the physicians' records. The vaccine appeared to be effective, for the incidence of mumps in the 145 vaccinated children--5.5%, or 8 cases--was significantly less (P less than 0.001) than the incidence in the 350 children considered susceptible to infection--21.7%, or 76 cases. The percentage of children who had been immunized decreased with increasing age, and acquisition of immunity through natural infection had the reverse trend; thus, the proportions of children susceptible to infection in each age group were about the same, and the age-specific attack rates were similar. Although the mothers were accurate in indicating absence of vaccination, they incorrectly indicated vaccination of their children 43.0% of the time; this error in reporting could influence vaccine administration in older children. Our findings suggest that mumps vaccination may substitute for natural illness in immunizing populations, and that more extensive use of the vaccine over a broader age range is required to prevent similar epidemics in the future.


Role of psychiatry in the phenomenon of cults.

Religious cults and particularly their attraction for young people are receiving increased attention. There is currently considerable controversy about the role of governmental bodies in understanding and regulating cults and their effect on members. Regardless of their effect on the members of the cult or movement, particularly new members who are often adolescents, membership in a cult produces severe familial tensions. The cult members often develop opinions and modes of behaviour so diametrically different from their families of origin that psychiatrists are often consulted with the view to understand, treat and correct what is seen as behavioural aberration by the families. The phenomenon of religious cults does not seem to be of a passing nature and it is therefore imperative that psychiatrists have a comprehensive and clear a knowledge of the concepts and activities of cults, their seeming effects on young people and their families, and some of the reactions they have caused in society.


Relationship between abortion and child abuse.

Although permissive abortion has been advocated on the grounds it will reduce the prevalence of child abuse and infanticide, there is no evidence to prove it has. There is a growing concern that it may have contributed to the problem. This article outlines eight possible methods whereby an increasing rate of abortion will lead to an increasing rate of abuse. There is evidence that an abortion results in depression which hinders mother-infant bonding in a subsequent pregnancy. An abortion of the first pregnancy may interrupt the developing bonding mechanism and interfere with the ability to bond to the next infant. If the hypothesis is correct, medicine by endorsing abortion on request may be jeopardizing the safety and care of a large number of children.


Family studies and changing concepts of personality development.

Many of the most significant changes in concepts of personality development and maldevelopment derive simply from belated appreciation that the child grows up in a family; and that the child requires considerable positive input from those who raise him to grow into a reasonably integrated person. Only recently have psychiatrists and psychoanalysts begun to focus on the influence of the family transactions throughout the formative years. The paper briefly presents the requisites a family must provide to assure the integrated development of its offspring and groups them under four headings: the parental nurturant functions that change with each phase of the offspring's development; the influence of the dynamic organization of the family on the offspring's intrapsychic structure, affecting self-boundaries, gender identity, superego directives, and so forth; conveying through family transactions the basic social roles and societal institutions to the child; transmitting the instrumental techniques of the culture, and particularly its language with its system of meanings and logic upon which virtually all ego functioning depends. The paper considers the evidence that the "choice of the neurosis" -- or more correctly, the choice of the psychiatric syndrome -- does not depend only upon fixation at various phases of pre-genital development, but also, and perhaps primarily, upon the panphasic influence of the intrafamilial environment. It is of particular importance to recognize that there is a very direct relationship between the family transactions, the separation-individuation process, bounary formation, the attainment of various degrees of object constancy, problems of splitting, superego directives, and what can be conscious and what need be repressed into the unconscious. The failure to recognize the import of the family has interfered with the formation of an integrated developmental theory that can unite various aspects of the developmental process that have remained more or less isolated from one another -- drive theory, object relations, ego psychology, separation-individuation, and cognitive development. Finally the question is raised if in providing guidance to parents we have been amiss in not focusing on such matters as who the parents are, how they relate to one another as well as to the child, the values they communicate by their behaviour -- matters that are fundamental and to which almost all else is secondary, but about which relatively little has been said or taught.


[The "bad mother" to the vulnerability of the parent child relationship].

This paper summarizes the results of a longitudinal study on young asthmatic children and particularly on the mother-child relationship in this illness: At both observation times--14 to 30 months and 4 to 6 years--the majority of the children appeaed to be developing in a very adequate manner, both in the area of autonomy and opposition. Similarly, in most situations, the mothers appeared quite adequate in the face of their child's illness, and mother-child relationships, generally, seemed harmonious. However, a certain vulnerability in the area of opposition was more marked in a few cases, more frequently between 4-6 years than between 14-30 months. The author attempts a brief history of the development of the concept of the "bad mother" who has become a scapegoat not only in childhood asthma but also in many illnesses encountered in child psychiatry. In questioning the role which may have been played by dynamic theories in this evolution, psychoanalytic writings are reviewed (for example, S. Freud, M. Klein, Spitz, Brody) and it is hypothesized that psychoanalytic theory has had more of a catalytic than a causal influence in relation with a strong tendency in our culture to the eclosion of negative attitudes toward the mother in her relationship with her child. The emphasis placed by North American culture on the nuclear family, the hypertrophy of the maternal function coupled with a paternal role much reduced in time, as well as the almost complete disappearance of maternal substitutes, have all probably greatly influenced the development of this concept of the "bad mother". The author notes however, that happily, in recent years some child development theories insist on the concept of mother-child interaction and on the mutual role that mother and child have on one another in their exchanges. A review is made of the work of Sander, Bowlby, Schaffer, Lewis and Rosenblum which demonstrates this new trend. The author also studies the question of vulnerability within parent-child relationships, leading to the appearance of child psychopathology, and discusses the development of methods which could help in its early detection. Recent attempts in this direction are reviewed, particularly those of Broussard, Gray et al., Lézine. The importance of Thomas and Chess' work is particularly underlined, which emphasizes the specific interaction between the temperamental characteristics of the child and the parents' specific responses to them, at all levels of development. More recent studies by Brazelton et al. and by Korner are also reviewed, suggesting a very early interaction between mother and child. The author concludes by briefly developing the preventive implications of these works and stressing the importance of closely following the efforts made at pre- and post-natal levels which may have much influence in the early prevention of psychopathology in parent-child relationships.


Psychopharmacology education in psychiatry.

This study has documented resident dissatisfaction with education in psychopharmacology in one large university and has proposed several solutions. These include: - increased awareness of standards of knowledge necessary for a consultant. - the establishment of a central educative office of clinical psychopharmacology to encourage dissemination of selected literature and to facilitate residents' research under supervision. - recognition that not all staff should be considered capable to provide psychopharmacology supervision and that each hospital should have a designated psychiatrist with special expertise in psychopharmacology. - developing study groups for the purpose of teaching critical evaluation of the literature. - increasing encouragement for residents' participating in clinical research - awareness of residents' difficulties in learning "emotional illness, rejection of biological therapies, and knowing what is expected or not suited to psychiatry" and appropriate actions to alter these. - increased use of audio aids, self-teaching manuals and journals to augment lectures and texts. - increased emphasis on training selected senior residents in how to teach.


Beginning psychoanalysis of a 16 year old autistic girl: the first three months.

This clinical report attempts to show some aspects of the first three months of analysis with a 16 year old autistic girl with some conceptualization of the technical difficulties of instituting psychoanalysis with such a patient, as well as some conceptualizations of the material itself.


Evidence of brain dopamine deficiency in schizophrenia.

It is proposed that the increased dopamine function suggested by the dopamine hypothesis of schizophrenia is a dopaminergic postsynaptic receptor supersensitivity resulting from a dopamine deficiency. In support of this, three double-blind controlled studies conducted on drugs which alter brain dopaminergic activity in a manner different from that of classic neuroleptics are reported. 1) alpha-methyldopa-neuroleptic interaction proved efficacious for schizophrenic positive symptoms but only on a short-term basis. 2) Rubidium improved negative symptoms rapidly, and in contrast has a late onset of action on positive symptoms of schizophrenia. 3) Tryptophan-benserazide was efficacious in controlling both negative and positive symptoms of schizophrenia (although less so than chlorpromazine). It is concluded that currently accepted modes of pharmacological therapy (classical neuroleptics) are in the short-term controlling the dopamine supersensitivity secondary to a deficiency, but contributing in the long-term to increase the dopamine deficiency, and so exacerbate the supersensitivity. More effective forms of treatment may involve the use of agents which alter dopamine activity without inducing dopamine supersensitivity.


10 year survey of pretrial examinations in Saskatchewan.

The results of a survey of pretrial examination cases admitted to the provincial psychiatric hospital in Saskatchewan from 1966 to 1975 are reported. The demographic and psychiatric data and data from the psychiatric reports to the Court are analyzed. Some deficiencies noted in the reports to the Court are discussed and some remedial measures are suggested.


Psychosexual aspects of the panic-fear personality types in asthma.

Numerous earlier studies have demonstrated the close relationship between MMPI Panic-Fear categories and various medical outcome measures in asthma. The present study relates MMPI Panic-Fear categories to psychosexual development. Specifically, High Panic-Fear patients demonstrate oral preoccupations, Low Panic-Fear patients demonstrate anal preoccupations, while Moderate Panic-Fear patients do not demonstrate pre-Oedipal preoccupations. Thus, MMPI Panic-Fear categories, useful in predicting medical outcome measures, have now been related to developmental levels, with the explanatory power of developmental concepts as well as their implications for psychological treatment.


Psychiatric implications of the mitral valve prolapse syndrome (MVPS).

The mitral valve prolapse syndrome (MVPS) is an infrequent outcome of mitral valve prolapse, a common and usually benign structural abnormality. Psychiatric patients often present with symptoms indistinguishable from MVPS, knowledge of which is thus essential for differential diagnosis. Even when prolapse of the mitral valve is detected, the symptoms may be variously determined by both physical and emotional factors. Four illustrative case histories are presented.


Studies of the psychosocial adjustment of the hearing-impaired: I. Adolescents and their families a pilot study.

There is a general pessimistic view found in the literature that defends a hypothesis that the consequences of a severe hearing impairment on psychosocial development aare many and severe. This pilot study of 20 adolescents who had experienced a profound hearing impairment from birth had the purpose of clarifying this issue. The findings of the study were not compatible with such pessimism. It is concluded that the teaching of an oral means of communication which facilitates education within a mainstreamed system, is compatible with good psychosocial adjustment. To confirm this optimism and to delineate the variables in good development, further study employing comparison groups is needed.


The referring therapist's expectations of inpatient treatment: some atypical variants.

The authors examined, over a three month period, modes of referral for inpatient treatment to a general psychiatric institute. What became apparent were several unconscious or unexpressed motivators in the therapist's referral which were noted as "unusual" or "atypical". These were identified and quantified into a list of atypical variations of the standard referral, which is presented, together with a description of each, and illustrative case material. The authors note there is a practical relevance to this, in that for each atypical variant there are pitfalls and potential for mismanagement, which if not recognized could well lead to a deleterious outcome for the patient and the therapists involved.


Therapeutic milieu: a dynamic approach.

This paper deals with the establishment of a therapeutic milieu in an acute care general hospital setting. The rationale and structure are defined, and dynamic considerations are elaborated. Conclusions are drawn from our experience suggesting that the therapeutic milieu is a viable and a more effective treatment delivery system than that provided by conventional inpatient units.


The man who became angry once: a study of overcontrolled hostility.

Recent developments in the study of violent behaviour have led social scientists to examine the concept of Overcontrolled Hostility. This case report describes the history of an overcontrolled individual who was examined in a Maximum Security Hospital after having shot his wife. The presentation of this case includes a brief theoretical perspective, as well as the results of psychiatric and psychological examinations.


Re-examination of the clinical mental status examination.

The traditional "mental status examination", as taught in medical school, is critically reviewed. The disparity between what is practised and what is preached, is outlined. Specific tests alleged to give information about mental function are discussed, and their clinical utility is found to be debatable. It is concluded that the reliability and validity of the mental status examination would be well worth testing. Alternatively, more use should be made of standardized tests which are now in the hands of clinical psychologists.


Determination of the absolute configuration of mono-saccharides in complex carbohydrates by capillary G.L.C.

The absolute configuration of neutral monosaccharides, 2-acetamido-2-deoxy sugars, and uronic acids can be determined by capillary g.l.c. on SE-30 after glycosidation with (-)-2-butanol and protection of the remaining polar groups. The method is illustrated by application to mixtures of the constituent sugars of the capsular polysaccharide from Klebsiella type 57, alpha 1-acid glycoprotein, mucus glycoproteins, and the methylated, acidic polysaccharide from the coccoliths of Emiliania huxleyi (Lohmann) Kamptner.


Synthesis of p-nitrophenyl 2-O-alpha-D-mannopyranosyl-alpha-D-mannopyranoside and p-nitrophenyl 6-O-alpha-D-mannopyranosyl-alpha-D-mannopyranoside.

Crystalline 2-O-alpha-D-mannopyranosyl-beta-D-mannopyranose octaacetate was synthesized by condensation of tetra-O-acetyl-alpha-D-mannopyranosyl bromide (3) with 1,3,4,6-tetra-O-acetyl-beta-D-mannopyranose. 6-O-alpha-D-Mannopyranosyl-alpha-D-mannopyranose octaacetate was prepared by condensation of 3 with 1,2,3,4-tetra-O-acetyl-6-O-trityl-alpha-D-mannopyranose. Fusion of each mannobiosyl octaacetate with p-nitrophenol was followed by deacetylation, to give the corresponding p-nitrophenyl (1 to 2) and (1 to 6)-alpha-D-mannobioside.


Structure of the capsular polysaccharide of Klebsiella K-type 63.

Structural investigation of the capsular polysaccharide from Klebsiella K type 63 by methylation analysis, periodate oxidation, and uronic acid degradation showed the repeating unit to consist of leads to 3)-alpha-D-Galp-(1 to 3)-alpha-D-GalpA-(1 TO 3)-ALpha-L-Fucp(1 to. This structure is identical to that of Escherichia coli serotype K-42 capsular polysaccharide. The 1H- and 13C-n.m.r. spectra of the original and modified polysaccharide are consistent with the foregoing structure.


[Synthese of 1-(5-deoxy-beta-D-ribo-hexofuranosyl)cytosine and 1-(2,5-dideoxy-beta-D-erythro-hexofuranosyl)cytosine, and their phosphates. Specificity of an mammalian (rat) ribonucleotide-reductase].

Mild, acidic hydrolysis of 3-O-benzoyl-1,2,:5,6-di-O-isopropylidene-alpha-D-allofuranose gave a diol that was selectively benzoylated at O-6 in high yield by intermediate conversion to the stannylene derivative. The 3,6-dibenzoate was converted to the 5-O-tosyl derivative and thence to a mixture of iodides, which were reduced with tributylstannane to 3,6-di-O-benzoyl-1,2-O-isopropylidene-alpha-D-ribo-hexofuranose (6). Acetolysis gave an anomeric mixture of diacetates, which, when treated with N-acetylbis(trimethylsilyl)cytosine gave the protected nucleoside, which was deprotected to free "homocytidine", 1-(5-deoxy-beta-D-ribo-hexofuranosyl)cytosine  (11), by alklaine methanolysis. This was N-acetylated and then treated with acetone to give a protected nucleoside, which was labelled by oxidation to the aldehyde, reduction with sodium borotritide, and deprotection. Acidic methanolysis of 6 gave a mixture of methyl 2,6- and 3,6-di-O-benzoylfuranosides, the hydroxyl groups of which were treated by the tetrachloromethane-triphenylphosphine reagent to give the 2-chloro-2-deoxy (21) and 3-chloro-3-deoxy derivatives. Reduction of 21 gave methyl 3,6-di-O-benzoyl-2,5-dideoxy-D-erythro-furanoside, further transformed in 1-(2,5-dideoxy-beta-D-erythro-hexofuranosyl)cytosine mixed with the alpha anomer. Phosphates and diphosphates of the nucleosides were prepared by extensions of known methods. The phosphate and the diphosphate of 11 act neither as substrates nor as inhibitors of a ribonucleotide-reductase from rat asicites tumor.


Sub-mitochondrial and sub-microsomal distribution of creatine kinase in guinea pig myocardium.

Mitochondrial and microsomal fractions were isolated from guinea pig myocardium by differential pelleting. The mitochondrial fraction was subjected to analytical subfractionation by sucrose density gradient centrifugation and the gradient fractions assayed for marker enzymes for the various mitochondrial compartments, viz outer membrane (monoamine oxidase), intermembranous space (adenylate kinase), inner membrane (Mg2+-dependent ATPase and cytochrome c oxidase) and mitochondrial matrix (malate dehydrogenase), and for creatine kinase. Both creatine kinase and adenylate kinase were released by suspending the mitochondria in 50 mmol . litre-1 sodium phosphate buffer. Sonication or disruption with the detergent, digitonin released the adenylate kinase but the creatine kinase remained associated with the inner membranes. Subsequent salt treatment desorbed the creatine kinase from these membranes. It is concluded that creatine kinase is located to the outer aspect of the inner mitochondrial membrane. Analytical subfractionation of the microsomal fraction clearly resolved markers for the sarcolemma (5'-nucleotidase), outer mitochondrial membrane (monoamine oxidase) and endoplasmic reticulum (neutral alpha-glucosidase and RNA). Creatine kinase was localised in the endoplasmic reticulum particularly the smooth membranes.


Excitation-contraction coupling in normal and myopathic hamster hearts III: functional deficiencies in interstitial glycoproteins.

Extracellular and surface bound Ca is essential to excitation-contraction (E-C) coupling in mammalian cardiac muscle. In intact hearts from cardiomyopathic hamster with congestive heart failure, a concomitant decrease in the Ca content of a superficial pool was associated with the reduced contractility. Ca binding to cardiac sarcolemmal ghosts prepared from these hearts revealed two binding sites by Scatchard plot. In normal hamsters, the low affinity site had a capacity of 114 nmol Ca.mg-1 protein, a KD of 1.5 mmol . litre-1 and was sensitive to neuraminidase treatment but not to 100 mmol . litre-1 Na, K, or Li, Ca binding in vitro approached a 1:1 relationship with the sialic acid content of the ghosts, 159 nmol . mg-1 protein. The activity of the enzyme responsible for glycosidically linking sialic acid to interstitial and sarcolemmal glycoproteins, sialyltransferase, was reduced from 1.80 to 0.41 pmol . mg-1 protein in the myopathic hearts. We suggest the functional defect in the hamster cardiomyopathy is a reduction in sialyltransferase activity leading to the deficiency in surface sialic acid residues. As a consequence, contractility is reduced, but Ca influx is increased. Reflex sympathetic activity increases Ca influx resulting in "Ca overload" and eventual cellular necrosis.


Estimation of circulatory parameters in patients with acute myocardial infarction. Significance for calculation of enzymatic infarct size.

Estimation of infarct size from enzyme activities in plasma or serum presupposes known values of circulatory parameters such as the extravascular distribution volume Ve and the permeability constant P for the transport of enzyme between intravascular volume Vi and Ve. In man, parameter values are used that are extrapolated either from values found in the dog or from turnover studies of non-myocardial proteins. Large systematic errors can be introduced in this way, as demonstrated in this study. It is shown that by simultaneous determination of two different enzymes in the same patient, estimates of circulatory parameters are obtained. The method is applied to creatine kinase (CK) and alpha-hydroxybutyrate dehydrogenase (HBDH) plasma activities in 36 patients with acute myocardial infarction (AMI). The following results are obtained: 1. Exchange of enzyme between Vi and Ve is much slower and clearance of CK is much faster than presently assumed in the literature. 2. Release of CK and HBDH into the circulation is proportional to the amounts of these enzymes present in the myocardium. This finding is supported by data on early enzyme release. 3. Quantitation of HBDH release needs a two-compartment model, while for CK a one-compartment model can be used in good approximation. 4. Release of CK and HBDH after AMI continues up to 96 hours. 5. Using obtained parameter values, a simulated model demonstrates that estimation of clearance rates of CK from exponential fits on plasma levels results in large errors. This may explain recent conflicting results in validation of enzymatic estimates of infarct size.


Prophylaxis of ventricular fibrillation after acute experimental coronary occlusion by chronic beta-adrenoceptor blockade with atenolol.

Acute occlusions of the left circumflex coronary artery were performed in open-chest dogs. A control group (n = 19) was compared with three groups (total n = 17) pretreated once daily with different doses of the cardioselective beta-blocking drug atenolol (ICI 66 082) given by mouth for 5 days. Only animals without coronary collateral vessels were examined, having a mortality rate of 100% in the control group. Arrhythmias and ventricular fibrillation during the first 30 min after coronary occlusion showed a biphasic distribution in time (phase 1a and 1b). A lower degree of beta-adrenoceptor blockade reduced the incidence of arrhythmias and ventricular fibrillation in phase 1a, but fibrillation occurred in all animals during phase 1b. A higher dose of the beta-blocking drug protected the animals from ventricular fibrillation, and arrhythmias in phase 1a were greatly reduced. At all times the ventricular fibrillation threshold in the group pretreated with atenolol was significantly higher than in the control group. In both groups a significant decrease in ventricular fibrillation threshold was found only during phase 1a. The greater sensitivity of phase 1a arrhythmias to beta-blockade and the lack of a decrease in ventricular fibrillation threshold during phase 1b might indicate differences in the genesis of arrhythmias and fibrillation in phases 1a and 1b.


An in vivo study of the total occlusion method for the analysis of forward and backward pressure waves.

The arterial pressure wave, Pm, is composed of a forward travelling wave, Pf, and a backward travelling wave, Pb, resulting from partial reflection of PI at the peripheral beds. The magnitude of Pb depends on the degree of vasoconstriction. Total occlusion of the vessel distal to the pressure measurement site results in a wave which is equal to 2Pf. Subtraction of the derived Pf wave from Pm gives Pb, provided there is no re-reflection of Pb by proximal discontinuities. To test the validity of this total occlusion method for the determination of the components of Pm, measurements were carried out in an anaesthetised dog and the results compared with the method of Westerhof et al., (1972). The measurements were made at three arterial sites: 1. in the aorta just proximal to the junction of the renal artery; 2. at the termination of the aorta; and 3. in the femoral artery. The magnitude of Pb was varied by the infusion of vasoactive drugs. There was good agreement between the two methods at site 1 but at the other two sites the agreement was less good. It is shown that this is the result of re-reflection of the backward travelling waves produced by the occlusion at the aortic termination and the renal artery junction.


A chronically implantable catheter-tip micromanometer (JSI 0400) that can be calibrated after implantation.

This paper describes a catheter-tip micromanometer for chronic left ventricular pressure measurements which can be calibrated in the animal after implantation. The calibration curves are linear, both in vitro and in vivo. Good zero-stability is reached after 1 week of implantation. The duration of function of the device is 3 to 6 months.


Flow in the thoracic aorta.

Pulsed ultrasonic Doppler velocimetry and theoretical flow analysis have been combined to improve the knowledge and understanding of aortic velocity profiles and wall shear. From the theoretical point of view, particular aspects of the flow were developed, concerning the vorticity in the aorta, the interior velocity distribution, the boundary layer, the flow after separation and the effects of the branches. The experimental approach was performed on dogs, using pulsed ultrasonic Doppler velocimeter providing real-time acquisition of the instantaneous velocity distribution along vascular diameters and perivascular probes designed for bidimensional measurement of velocity distribution. The good agreement found between theory and the experimental velocity profiles has led to comparison of the assessments of axial shear. The peak of the measured shear agrees well with the calculated one; the largest observed shear, obtained at the level of the initial part of the descending thoracic aorta, varies from 4.5 Pa to 7.5 Pa depending on the cardiac output. Finally initial attempts have been made to correlate atheromatous wall lesion localisation with the flow and shear variation.


Cardiac consequences and treatment of disopyramide intoxication: experimental evaluation in dogs.

A slow (1.18 mumol.kg-1.mm-1) intravenous infusion of disopyramide (mol.wt 339) was given to 8 adult Beagle dogs. An initial phase of slow decline in cardiac output and broadening of the QRS complex on the ECG, with systolic blood pressure maintained above 13.5 kPa (100 mmHg), was followed by a phase of rapid circulatory failure without a correspondingly dramatic change in ECG appearances. Underventilation and cardiac arrhythmias were observed only in the agonal phase after several minutes of circulatory arrest. They were not therefore the primary cause of death, which was due to failure of myocardial contractility. Three positively inotropic drugs (isoprenaline, dopamine, and glucagon) are shown to be capable of restoring the failing circulation, provided they are given before the phase of complete circulatory standstill. In this respect isoprenaline appears superior to dopamine and glucagon.


Regional 99m technetium diphosphonate uptake in experimental dog heart infarct: relation to duration and severity of ischaemia.

Regional uptake of 99mTechnetium diphosphonate was compared with regional myocardial blood flow 6, 12 and 24 h after the onset of myocardial infarction in dogs, and with regional creatine kinase depletion 24 h after the onset. Uptake of the imaging agent increased from 6 to 24 h, but no consistent relationship could be demonstrated between regional myocardial blood flow and regional uptake of the diphosphonate nor between uptake and regional creatine kinase depletion at the centre or border of the infarct. In addition, inappropriately high levels of 99m Technetium uptake could be demonstrated in the epicardial layer of the normal tissue surrounding the infarct. We conclude that diphosphonate uptake is not quantitatively related to the severity of ischaemia, and that use of this substance for imaging may over-estimate myocardial infarct size.


Reliability of the maximum derivatives of left ventricular pressure and internal diameter as indices of the inotropic state of the depressed myocardium.

The effects of inotropic stimulation and increases in end-diastolic diameter, aortic pressure, left ventricular end diameter size, mean arterial pressure, and heart rate on maximum rate of change of left ventricular pressure (dP/dtmax) and diameter (dD/dtmax) were studied in eight dogs. Responses were studied in the normal conscious state, during myocardial depression due to high doses of pentobarbital or propranolol, and after bilateral cardiac sympathectomy. In all states studied, both dP/dtmax and dD/dtmax were substantially augmented by inotropic stimulation with isoprenaline and were less influenced by changes in end-diastolic diameter, mean arterial pressure and heart rate. It is concluded that both indices are highly sensitive to the contractile state of the left ventricle and relatively insensitive to haemodynamic alterations in both normal and depressed hearts.


Measurement of haemolysis in patients with prosthetic heart valves.

Haemolysis following prosthetic heart valve insertion can be precisely and sensitively measured by means of a 59Fe ferrokinetic technique. Results obtained in a small series of patients with either Starr-Edwards or Brunwald-Cutter valve replacement are presented.


Nonobstructive coarctation.

Roentgenographic studies, including plain chest roentgenography, thoracic aortography, and coronary angiography, were performed in seven adult patients with nonobstructive coarctation, a congenital deformity of the upper thoracic aorta. The chest roentgenographic findings were compared with those of ten patients with obstructive coarctation studied during the same period. A great similarity was found in the morphology and associated lesions of these two conditions, which supports the idea that nonobstructive and obstructive coarctation are stages of the same disease. Patients with nonobstructive coarctation had a more prominent aortic arch, and the indentation in the thoracic aorta was higher than in patients with obstructive coarctation. In addition, patients with nonobstructive coarctation had no rib notching on plain chest roentgenograms. Angiographic evaluation in patients with nonobstructive disease demonstrated the anatomic lesion, the absence of collateral circulation, and the commonly associated anomalies of the aortic valve.


"Balloon valvulotomy" of congenital pulmonary valve stenosis with tricuspid valve insufficiency.

The rare congenital anomaly of pulmonary valve stenosis and massive tricuspid valve insufficiency with intact ventricular septum is a lethal condition without reported survival after attempted treatment. In a neonate suffering from this syndrome, the pulmonary valve stenosis was relieved by rupturing the fused valve with a balloon catheter introduced transvenously. The desperate condition of the patient quickly improved after this procedure, with subsequent disappearance of the tricuspid valve incompetence. Balloon rupturing of fused valves at angiography may represent a therapeutic alternative in cases in which surgical valvulotomy is associated with a high mortality.


Collateral circulation in stenosis or occlusion of the renal artery.

The abdominal angiograms of 381 patients were critically reexamined for the existence of collateral circulation in cases of renal artery stenosis or occlusion. Typical renal artery stenosis was found in 39 patients; among these, 17 had a collateral circulation, which was extrarenal in 15 and intrarenal in two. Collateral circulation involving the lumbar arteries was most common. In two patients a collateral circulation was established via the inferior mesenteric artery.


Aneurysm of a persistent sciatic artery.

Angiographic examination in a patient with sciatic-like pain on the right side and a firm, pulsatile, non-tender mass in the right buttock revealed a large sciatic artery aneurysm. The aneurysm was successfully resected at surgery. The primitive sciatic artery is the main arterial supply to the lower extremities in the 9-mm embryo. Its persistence, while very rare, is of clinical significance because of the tendency for aneurysms to develop in the artery. Surgical resection is indicated in sciatic artery aneurysms because of the danger of rupture or embolic occlusion of arteries distal to the aneurysm.


Spontaneous intermittent reversal of blood flow in intrahepatic portal vein branches in cirrhosis of the liver.

The intrahepatic portal venous flow in cirrhosis of the liver was evaluated by percutaneous transhepatic portography and hepatic arteriography. Spontaneous reversal of flow in segmental portal vein branches was documented. Changes in hepatic arterial inflow and portal venous pressure may result in intermittent changes in the direction of flow in segmental portal venous branches within the cirrhotic liver. Segmental reversal of blood flow seems to be the precursor of total hepatofugal portal flow.


On the progenitor cell migration velocity.

An attempt is presented to extract cell kinetic information from histomorphological features. It is applicable to rapidly proliferating tissues like the intestinal epithelium. Each replicating tissue has an origin where cells are formed and a periphery toward which cells migrate. The migration path along which they move is denominated as tissue radius on which all cell positions are mapped. Cell migration on the radius is associated with cell proliferation at tissue origin. Each mitosis there is associated with the displacement of all cells distal to it by one cell position. The more mitoses positioned between a cell and tissue origin, the greater its migration velocity. It is possible therefore to derive the cell migration velocity v(x) from the cumulative mitotic distribution on the radius, N(x). v(x) = N(x)/tm (tm = mitotic time). In this form v(x) represents also cell production at any point on the radius and may serve for the computation of other cell kinetic parameters like generation time. These arguments are illustrated on the rat incisor tooth inner enamel epithelium which has been studied in the normal and rapidly erupting tooth.


Testosterone-induced cell proliferation in the accessory sex glands of mice at various times after castration.

The proliferative response to testosterone in the accessory sex glands (seminal vesicle and coagulating gland) of castrated pale Balb/c mice has been examined by pulse and continuous thymidine-labelling experiments, and by the fraction of labelled mitoses technique. Progressive reductions in cellularity followed castration, and by varying the time elapsing between castration and the initiation of testosterone treatment, it was clear that the size of the response depended upon the number of cells in the tissue, relative to the normal complement. Interpretation of FLM data was difficult in periods where proliferative rates changed rapidly. We have attempted to explain the cell kinetic events by postulating a G0 compartment, form which cells are stimulated to enter the proliferative cycle before subsequently returning to an out of cycle state. It was thought unlikely that substantial changes in cell cycle time occurred. In both the accessory sex glands, the overall form of the continuous thymidine labelling curves showed that most proliferative cells entered DNA synthesis in a shorter time after stimulation at 14 days after castration than they did at 3 days after castration. The data were not consistent with cells moving deeper into G0 with time after castration. In the seminal vesicle almost all epithelial cells were potentially proliferative by 3 days after castration. In the coagulating gland only 30% were potentially proliferative at 3 days, increasing to 85% at 14 days after castration. However, such proportional increases represented much smaller changes in terms of absolute numbers of cells, because of a concomitant decline in cellularity from 3 to 14 days after castration.


Differential lethal effects of both cytosine arabinoside and hydroxyurea on jejunal crypt cells and testosterone-stimulated accessory sex glands.

DNA-synthesizing cells from mouse jejunal crypts and accessory sex glands respond differently to the DNA synthesis inhibitors cytosine arabinoside and hydroxyurea. A single injection of either agent brought about a rapid inhibition of thymidine labelling in both the tissues. Whilst both agents had a lethal effect upon the majority of S-phase cells in the crypts, only a minority of S-phase cells in the accessory sex glands showed evidence of necrosis. These differences are considered in the context of possible physiological differences between continually dividing cells and putative G0 cells. The accessory sex glands are normally quiescent proliferative tissues. They were stimulated to undergo DNA synthesis and later mitosis by testosterone propionate injections, commencing three days after castration. Cytosine arabinoside was the more effective cytocidal agent in the accessory sex glands, and when two injections were scheduled so as to affect a large number of DNA-synthesizing cells, a compensatory hyperplasia was evoked. In the coagulating gland, this compensatory response involved the proliferation of many cells which, in the absence of cytotoxic perturbation, would be non-proliferatie (Q cells).


Growth kinetics of a rat mammary tumour transplanted into immune-suppressed mice.

The growth kinetics of a transplanted rat mammary tumour and its xenografts in immune-suppressed mice were studied using the technique of labelled mitoses. Growth of the tumour in rats was regular and uniform but when transplanted into mice the growth of the implants was irregular and generally slower. The second passage tumours in mice showed rapid and regular growth with a volume doubling time approximately half that for the tumours in the rat. Values for the G1 phase duration, intermitotic time and growth fraction were greater for the tumours in the mouse although the data for the first passage in mice were difficult to interpret. The kinetic changes between the rat and mouse hosts primarily reflect a large and variable amount of cell loss from the first passage xenografts in the mouse, with adaptation by the second passage towards reduced cell loss.


Correlation between cell size and position within the division cycle in suspension cultures of Chang liver cells.

Chang liver cells from exponentially growing suspension cultures have been separated by sedimentation at unit gravity. Determinations of the protein content per cell showed that the fractionation procedure resulted in good separation of cells of different size. On the other hand, the DNA content of individual cells from the fractions, as determined cytofluorimetrically, indicated considerable heterogeneity in the size of cells from the same stage of the division cycle. On the basis of earlier results on intermitotic growth and the variation in the length of the cell cycle in homogeneous cell populations, a mathematical model has been constructed and tested using a computer program. The present results on the size distribution of cells from the different stages of the mitotic cycle are consistent with a regeneration of size heterogeneity in each cell generation, as a result of the dispersion of intermitotic times. The variation in cell cycle times may be related to a probabilistic event in the G1 period. In the mathematical model it was necessary to include a mechanism by which the regeneration of abnormally large cells is prevented. The experimental data are compatible with a gradually increasing inhibition of growth in cells larger than a certain size (circa 400 pg protein per cell).


Cell proliferation of carcinoma in Bilharzial bladder: an autoradiographic study.

The rate of cell production in thirty-five cases of carcinoma in Bilharzial bladder was evaluated from the labelling index after in vitro incubation with [3H]TdR. Squamous cell carcinoma was the most frequent histological type in this series and had a median LI of 8.0% which corresponds to a potential doubling time of 5.9 days. In squamous cell tumours the LI increased with the histological grade. Transitional cell tumours had a somewhat greater LI. In all histological types the LI was significantly greater in the deep infiltrating parts of the tumour than in the superficial parts. The discrepancy between the estimated potential doubling time and the growth rate normally attributed to such tumours suggests the existence of an extensive cell loss factor. Areas of focal or diffuse mucosal hyperplasia were associated with increased LI.


Particle-induced erythropoietin-independent effects of erythroid precursor cells in murine bone marrow.

A possible regulatory action of phagocytic cells on erythropoiesis was investigated by infusion of inert polystyrene latex particles (LAT). LAT appeared to induce changes in the femoral content of erythroid progenitor cells. These changes were most pronounced in primitive erythroid progenitor cells (BFUe) and appeared to be gradually damped in more differentiated populations (CFUe and erythroblasts). LAT did not influence granulocyte/macrophage progenitor cells (CFUc). The effects of LAT could not be attributed to changes in the systemic erythropoietin (EP) concentration. Administration of dexamethason nullified the effect of low doses of LAT, suggesting that phagocytosis of the particles is essential to the observed effects. Erythroid burst formation was previously found to be dependent on a bone marrow associated activity, termed BFA (burst feeder activity). BFA acts as an in vitro inducer of EP-responsiveness in BFUe. In this study it was found that LAT-induced changes in femoral erythroid progenitor cell content were characteristically preceded by corresponding changes in BFA. It was concluded that BFA-associated cells probably play a role in vivo in the early differentiation of erythroid progenitor cells. The present data are interpreted as direct in vivo evidence supporting a two-step regulatory model operating in erythropoiesis and provide evidence that phagocytic cells are a component of the erythroid haemopoietic inductive micro-environment.


A mathematical model of thrombopoiesis in rats.

A mathematical model of thrombopoiesis in rats is presented. This has four compartments; stem cells, megakaryocytes, thrombocytes and thrombopoietin. A high thrombopoietin concentration influences bone marrow proliferation in three ways. Firstly the stem cells are stimulated and a slow increase in megakaryocyte number follows. Secondly there are additional endomitoses in the (early) megakaryocytes resulting in an increase in megakaryocyte volume. Thirdly the megakaryocyte maturation time is shortened. The parameters of the model are determined from experimental values for the normal, maximum and minimum proliferation rates, maturation times and destruction rates. The model is tested by comparing simulated results for acute and chronic thrombocytopenia and thrombocytosis with experimental curves from the literature. The model and data agree within the limits of experimental error. Not all of the thrombopoietic regulatory system is known yet, so some important alternative hypotheses are investigated and compared with the model. Several hypotheses have been excluded in this way.


The mineralization processes in teleost fish scales.

In Teleost fish scales, growth and mineralization are continuous. Different mineralization processes can be distinguished. The external layer of the scale is the first to be mineralized and may be classified as the initial calcifying structure of the scale. The initial calcification loci are matrix vesicles of cellular origin always observed during the formation of this layer. This mineralization process takes place progressively, closely following the elaboration of the organic matrix in the scale periphery. The outer limiting and internal layers of the scale are developed after the external layer has been formed. A mineral substance is deposited without the mediation of matrix vesicles, but in contact with the previously mineralized external layer. This type of mineralization is called subsequential. However, the mineralization of the outer limiting layer closely follows the secretion of a collagen-free organic matrix and is thus different from the mineralization of the internal layer in which the calcification front remains remote from the collagen matrix surface and corresponds to a delayed mineralization process. The isolated calcifications (Mandl's corpuscles) which develop in the unmineralized laminae of the internal layer are mineralized in the absence of matrix vesicles and without making contact with a pre-existing calcified tissue, probably by a heterogeneous nucleation of the collagen fibrils.


Keratinization of fish skin with special reference to the catfish Bagarius bagarius.

Histochemical reactions indicating keratinization have previously been demonstrated in parts of the epidermis of Bagarius bagarius. Fluorescence histochemistry and electron microscopy have now confirmed these results. Elevated areas of the epidermis are capped by a layer of dead cells with altered contents. On the outer aspect of these cells a dense layer, 18 nm thick, beneath the plasma membrane corresponds to the resistant envelope found in keratinized cells in tetrapod vertebrates. In Bagarius this layer does not extend to all faces of the keratinized cells, but a similar envelope has been detected in two other sites of piscine keratinized epidermis investigated, namely in the breeding tubercles of Phoxinus phoxinus and in the teeth of Lampetral fluviatilis. In the elevated areas of Bagarius-epidermis, the epithelial cells undergo progressive changes in cytoplasmic organization as they ;ecome more superficial. The second tier from the surface is sealed by tight junctions and is separated from the overlying keratinized cells by a sub-corneal space resembling that found in keratinized amphibian epidermis. Histochemical evidence of a high lipid content in the outer layers of the epidermis correlates with the presence of lipid inclusions and lamellated membranous profiles in the material studied by electron microscopy. Histochemical results show that the fin skin of Blennius pholis is not keratinized, but secretes a cuticle, histochemically reactive for both proteins and glycoproteins.


Age as a factor in 6-hydroxydopamine-induced plasticity in the hypothalamus.

The question of age as a possible factor influencing the regenerative response of catecholaminergic varicosities in the hypothalamus was investigated in the supraoptic commissure and the paraventricular, periventricular, and dorsomedial hypothalamic nuclei of rats that had received intraventricular injections of the neurotoxin 6-hydroxydopamine when they were (1) neonates, (2) young adults, or (3) senescent adults. After post-neurotoxin survival for 4, 21, 56, or 180 days, the animals were perfused, and the hypothalamic tissue sections were cut and processed using a glyoxylic acid method for localizing catecholamines. Four days following neurotoxin administration, counts of fluorescent varicosities showed a significant loss of catecholamine varicosities in each of the four areas. Subsequently, at least partial restoration of numbers of catecholamine varicosities occurred in all hypothalamic areas in all three age groups. It is concluded that, following selective lesions induced by the neurotoxin 6-OH-DA, catecholamine varicosities were restored both in immature and mature groups. According to the evidence obtained experimentally, the rate of restoration was greater in the neonate group, whereas the percentage restoration attained varies according to the hypothalamic area studied and the age of the animal.


Cytochemistry and freeze-fracture of membranes isolated from the electrocyte of Electrophorus electricus (L.).

Membranes were isolated from the main electric organ of Electrophorus electricus and studied by means of cytochemistry and freeze-fracture. The membrane fractions consisted of vesicles inside-in as determined by localization of anionic sites using colloidal iron and cationized ferritin particles. The anionic sites were not homogeneously distributed on the surface of the vesicle. Freeze-fracture showed the presence of intramembranous particles associated with either protoplasmic (P) or extracellular (E) faces of the membrane. Regions of the membrane without particles were observed. The results are discussed in relation to the existence of association between intramembranous particles and membrane receptors.


Effect of methallibure (ICI 33,828) on the pituitary-gonad and the pituitary-thyroid axes of the Indian garden lizard, Calotes versicolor (Daudin).

The effect of methallibure (ICI 33,828) on the pituitary-gonad and the pituitary-thyroid axes of the Indian garden lizard, Calotes veriscolor was studied. Following administration of methallibure B2 (FSH) and B3 (ICSH) cells of the pars distalis exhibited significant alterations with concomitant changes in the seminiferous tubules, and in the interstitial cells and epididymis respectively. B1 (TSH) cells exhibited conspicuous hypertrophy and degranulation which was reflected in dramatic changes in thyroid morphology. The caudally localized acidophilic A1 (PRL) cells also showed hypertrophy, hyperplasia and intense granulation. The rostrally located A2 (STH) acidophils and the B4 (ACTH) cells were unaffected by the treatment. The possible model of action of this drug is discussed in the light of available literature.


Distribution and orientation of microtubules in milk secreting epithelial cells of rat mammary gland.

Quantitative ultrastructural analysis of mid-lactation rat mammary gland demonstrated that cytoplasmic microtubules were present in nearly all secretory epithelial cells examined. Most microtubules were oriented perpendicular to the apical membrane and were found in the apical and medial portions of the cell cytoplasm. There was no statistical difference between the number of microtubules associated with vesicles and the number that were not. Most vesicles which were in contact with microtubules were small (50 to 150 nm), appeared electron lucent and located in a supra-Golgi complex position. Many of these vesicles were seen to be aligned along the axis of longitudinally sectioned microtubules oriented perpendicular to the apical plasma membrane. As measured by a colchicine binding assay, the total tubulin content of mammary tissue from mid-lactation rats was about 107 micrograms/100 mg wet weight. Approximately 19% of the total tubulin was in polymerized form. This study provides evidence that microtubules may be involved in guiding transport of small secretory vesicles to the apical regions of cells for exocytosis.


The culture of tissue from the ovary of the goldfish Carassius auratus.

Small pieces of ovarian tissue derived from immature goldfish have been maintained in culture periods of up to three months. The progress of the culture was monitored by light and electron microscopy and showed that although degenerative changes occurred in the large oocytes the small oocytes and oogonia survived for the duration of the culture. Quantitative studies indicate that both oogonia and small oocytes increase in number during the first three weeks of culture and observations from experiments using 3H-thymidine support the idea that a limited proliferation can occur using the relatively simple technique described.


Incorporation of L-(3H)-fucose into glycoproteins of the adrenal gland of mice. Light microscope radioautographic study on semi-thin sections.

To study the biosynthesis and intracellular migration of glycoproteins in the adrenal gland, adult mice were injected intravenously with L-(3H)-fucose and killed from 10 min to 14 days after injection. Semi-thin sections of the adrenal glands were then processed for radioautography. Incorporation of labeled fucose occurred in the steroid-secreting cells of the three zones of the cortex as well as in the adrenalin (A) and noradrenalin (NA) cells of the medulla. At short intervals after injection, the main site of incorporation was the paranuclear region of the cells, suggesting uptake by the Golgi apparatus. Subsequently, labeled glycoproteins migrated from the paranuclear region to other cell sites. The labeling pattern observed in the adrenocortical parenchyme strongly suggests that the glycoproteins are transferred to lysosomes, lipofuscin granules and the cell coat (glycocalyx). Counts of silver grains clearly indicate that these glycoproteins undergo renewal. The qualitative and quantitative analysis of the radioautographs also suggest that glycoproteins, acting as intracellular carriers of steroids, may be released to the extracellular environment together with the hormones. Most of the glycoproteins synthesized by the A and NA cells of the adrenal medulla seem to be transferred to secretion granules in which they may play some role in the cytophysiology of these structures. It is likely that glycoproteins are released from the cells during exocytosis of secretory granules.


Seasonal changes in the reproductive system of the female white-crowned sparrow, Zonotrichia leucophrys gambelii, in captivity and in the field. 2. The incubation patch.

The ventral apterium of free-living female White-crowned Sparrows (Zonotrichia leucophrys gambelii) becomes an incubation patch during the breeding season. At this time, it loses its feathers, increases in wet and defatted dry weight, and undergoes marked histological alterations. At times of year other than the breeding season, the apterium consists of a low squamous epidermis and a thin, poorly vascularized dermis of dense connective tissue. The dermis is separated from subcutaneous tissue by an internal elastic lamina. During the breeding season, the epidermis is a proliferative, stratified squamous epithelium with well-defined basal, intermediate, transitional, and cornified layers; and the dermis consists of a superficial layer of collagen and a deep layer of highly vascular areolar connective tissue, noticeably edematous and mildly inflamed. Blood vessels are frequently in large groups in the center of the dermis. Edema and hypervascularity are most pronounced during incubation, but the epidermis is best developed during egg-laying. The apterium reverts to its basal state after the incubation period. Captive females, which do not breed, do not develop incubation patches. Estrogen is apparently responsible for feather loss and collagen synthesis. It and other unidentified hormones (probably prolactin and/or androgens produce the hypervascularity, edema, and epidermal growth.


A study of cells present in peripheral lymph of pigs with special reference to a type of cell resembling the Langerhans cell.

Large mononuclear cells with long, actively moving cytoplasmic veils were observed in lymph coming from the skin. The enzyme histochemistry and ultrastructure of these cells suggested that they are related to epidermal Langerhans cells and interdigitating cells in the lymph node. It has been reported that Langerhans cells and interdigitating cells play a role in contact hypersensitivity by taking up antigen and presenting it to thymus-dependent lymphocytes, and it is likely that the veiled cells in the lymph are also involved. After skin-painting with 1-fluoro-2,4-dinitrobenzene (DNFB), the veiled cells in lymph coming from the site of painting became more active and were observed contacting other cells present in the lymph; many large cellular aggregates were found. Since neutrophilic leucocytes and mononuclear phagocytes were the predominating cell types in this lymph, there was no evidence for a massive recruitment of immunocompetent lymphocytes at the site of painting. Neonatally thymectomized pigs do not develop allergic reactivity to DNFB. It is of interest that the number of veiled cells and their ability to form large cellular aggregates was not affected in these animals. Therefore, it is unlikely that the defect in responsiveness can be attributed to a failure in the function of veiled cells.


The collagen of the vertebrate peripheral nervous system.

Nerves and ganglia from a variety of fish, amphibian, reptilian and mammalian species were studied by optical and electron microscopy. Observations using the Picrosirius-polarization method strongly suggest that two different types of collagen fibers are present in the connective tissues of nerves and ganglia. Electron microscopy of nerves and ganglia showed the presence of two different collagen fibril populations, distinguishable on the basis of diameter, located in different compartments of these structures. Thicker fibrils are present in nerve and ganglionic epineurium. Thinner fibrils are present in the endoneurium, surrounding nerve fibers and ganglionic cells, and between the concentric layers of perineurial cells. These results were consistently observed in all species studied and very probably represent a general phenomenon in vertebrates.


Fine structure of sensory tubes on the antennule of Conchoecia spinirostris (Ostracoda, Crustacea). A new type of sensillum in crustaceans.

In addition to setae, the first antennae of Conchoecia spinirostris also bear soft sensory tubes (female: 4 tubes + 1 seta; male: 2 tubes + 3 setae). These tubes were examined electron microscopically. Each tube is divided into 4 regions: the stem, the bulbous region, the main region, and the tip. A tube contains 40--60 multiciliated dendrites, some hypodermal cells, and nonneuronal cells, and it has a specialized cuticle. Each dendrite develops within the tube, on the terminal 5--8 micron of its inner dendritic segment, approx. 25 cilia in a 9 X 2 + 0 pattern, whose rootlets are absent or only poorly developed. Each cilium splits up into 9 ramifications which extend into the tip. These ramifications partly take a spirallike course and form a ring in the distal main part beneath the cuticle. Their membranes often dilate into spindleshaped swellings. In the center of the middle and distal parts of the main region approx. 7 dendrites without cilia are located, one of them reaches into the tip. The poreless cuticle is extremely delicate and electron lucid. In contrast to the cuticle of the setae it is elastic and soft. Special substructures are described. The tubes are completely covered by a filamentous surface coat. Because of the structure and the thin walled nature of the cuticle, permeability for dissolved substances is assumed. The ciliary ramifications are likely to represent the receptive apparatus. The sensory tubes are interpreted as chemoreceptors. They can best be compared with the chemoreceptors of certain crustaceans, but differ strongly from the types of sensilla found in insects.


Stereological analyses of the structure of mitochondria in pigeon skeletal muscle.

The mitochondria in type-I and -II muscle fibres in the pectoralis major muscle of the pigeon (Columba livia) have been analysed using stereological techniques not previously applied in muscle biology. Mitochondrial volume fractions (VV) were estimated in different regions of each type of muscle fibre using randomly orientated sampling sectors within fibre profiles. These sectors were sub-divided into smaller sampling regions to provide accurate data on the intracellular distribution of mitochondria. Estimates of the external surface densities of mitochondria per unit volume of fibre, SV total surface, and also the densities of mitochondrial cristae, SV total cristae, were obtained using a specific technique derived for analysing anisotropic structures (Saltykov, 1958). The relative amounts of the random and orientated mitochondrial membranes were also estimated. Significant differences were found to exist between the different types of muscle fibres and considerable though constant variations in the intracellular arrangement of mitochondria were also found.


The fine structure of ventral prostatic secretory epithelial cells in older rats.

The ventral prostatic secretory epithelial cells in older rats were studied by light and electron microscopy. The cells vary in height in different parts of the same organ, and ultrastructurally they show the presence of a developed secretory apparatus such as well-developed Golgi body and abundant rough endoplasmic reticulum. They also show signs of a depressed secretory activity, involving occasional emiocytosis of apical secretory vacuoles and a paucity of condensing vacuoles in the Golgi region and above it. Further, they are characterized by the frequent occurrence of supra and paranuclear pleomorphic lysosomes.


Synaptic terminal parameters in unanesthetized rat cerebral cortex.

The ultrastructure of synapses from the molecular layer of parietal cortex was examined in two groups of unanesthetized rats. Rats of the first group were killed by stunning across the back of the neck, and those of the second group by the introduction of fixative through a preimplanted carotid artery cannula. Comparison of synapses from the two groups revealed that the distribution of synaptic types was the same. A larger percentage of synapses of the cannulated group has vesicle attachment sites than did those of the stunned group. The area and perimeter of the presynaptic terminals were significantly larger in synapses from the cannulated group, although the equivalent length of the postsynaptic thickening was less. The mean value for synaptic curvature was greater in the cannulated group, although over 80% of synapses in both groups had positive curvatures. No significant differences were found between the groups for the relationships between presynaptic terminal area and synaptic vesicle number, and between postsynaptic thickening length and synaptic curvature. Membrane recycling is suggested as a mechanism of accounting for the differences. The preponderance of postively-curved synapses in unanesthetized material may indicate a preponderance of functioning synapses.


Fusion of erythrolysosomes in epithelial cells of the sheep placenta.

In trophoblastic epithelial cells of the sheep placenta the breakdown of erythrocytes within complex erythrolysosomes was studied at the ultrastructural level. It was found that the formation of complex erythrolysosomes containing from two to several erythrocytes as a result of fusion of erythrolysosomes within the epithelial cells was a common occurrence when the epithelial cells engulfed a large number of erythrocytes. The erythrocytes enclosed in complex erythrolysosomes appear to be either in the same or in different stages of hemolysis. In the process of breakdown of erythrocytes within complex erythrolysosomes five successive stages of hemolysis could be distinguished. Acid phosphatase activity was demonstrated in the complex erythrolysosomes and appeared to be located in the angular interspaces between the erythrocytes and the lysosomal membrane. The fragmentation of complex erythrolysosomes with formation of small hemoglobin-containing lysosomes also occurred. The fusion of erythrolysosomes with formation of complex erythrolysosomes can be considered as an additional mechanism in the process of erythrocyte breakdown in the epithelial cells of the sheep placenta.


Transplantation experiments with the fat body of Calliphora: a morphometric study of induced ultrastructural changes.

Transplantation of fragments of the anterior fat body lobe of 4 day old feeding stage larvae into one day older hosts, which are at the end of feeding, leads to precocious induction of ultrastructural changes in the transplanted cells of the fat body. These changes include alterations in the mean relative and absolute areas of mitochndria, protein granules, lipid droplets and vacuoles. The extent of intracellular changes induced in the transplants depends on the physiological condition of the host. This confirms that alterations in the internal environment at termination of feeding induce prematamorphic changes in cells of the fat body.


Electron microscopic studies on radular tooth formation in the snails Helix pomatia L. and Limax flavus L. (Pulmonata, Stylommatophora).

The radular teeth are secreted at the posterior end of the radular gland and move slowly towards the buccal cavity where they start to function. Helix pomatia and Limax flavus were examined to determine whether the newly formed teeth already show their definite species specific shape, or whether they are gradually finished and moulded in the radular gland. Scanning electron micrographs of Helix pomatia show that teeth are secreted in the odontoblast region in their final form. Their surface is still uneven at the outset; the same is true for the newest teeth of Limax flavus. Older teeth ready for use have a smooth surface. This change seems to be brought about by secretory activity of the superior epithelium of the radular sac. Air-dried radulae, previously isolated by KOH maceration, show considerable artefacts at their posterior end. Maceration leads to shrinking of the newest teeth, but does not change their contours. The newly secreted but as yet unhardened teeth become greatly deformed during the drying process.


Morphological and functional study of the effect of isoproterenol on salivary gland cells.

The cellular mechanisms responsible for the structural and functional alterations produced in salivary glands by isoproterenol (ISP) were investigated. Postnatal rats were injected with ISP, and alterations in the structure and protein components of the submandibular glands were determined. Normal age-dependent protein patterns detected by electrophoresis are attributed to the biochemical and functional differentiation of proacinar and acinar secretory cells and correlate with structural changes in these cells. Structural changes induced by ISP involve the acinar cells without detectably altering terminal tubule cells. In addition, synthesis of a specific protein by the glands is enhanced by ISP treatment. By comparing protein patterns in the submandibular glands of control and treated rats, it was concluded that ISP increases synthesis of a specific salivary protein normally produced by proacinar cells during a limited period of glandular development. These results suggest that a neurally mediated regulaotry mechanism that becomes altered by ISP plays a role in normal salivary gland development.


Structural alterations in proliferating, remodeling, and regressing tooth pulp arterioles.

In the continuously growing upper incisor of 100 g rats about 25 arterioles arise from an artery outside the tooth and pass through the apical foramen to run parallel to one another in the central part of the pulp, each supplying a well-defined sector of the migrating odontoblast layer. The arterioles pass through a cycle of proliferation, growth, remodeling, regression and decay, phase displaced in relation to each other. Proliferative and degenerative processes occur in the arteriole wall throughout the cycle, but vary considerably in intensity at different phases. Proliferation takes place by mitosis in the endothelium and the innermost smooth muscle cells. The degenerative process consists of reduction in size of smooth muscle cells by partial autodigestion and by cell death. When the odontoblasts reach the incisal extremity of the tooth, they die, and the associated regressed arteriole disappears. The system of pulpal arterioles has remarkable spatio-temporal features and each of its vessels appears to be in a state of sensitive structural equilibrium.


The surface connected canalicular system of carp (Cyprinus carpio) thrombocytes: its fine structure and three-dimensional architecture.

The presence and the three dimensional distribution of the surface connected canalicular system (SCCS) in thrombocytes of a teleost, Cyprinus carpio, were studied using a transmission electron microscope, a high voltage electron microscope and a scanning electron microscope. When the specimens were fixed routinely in glutaraldehyde followed by osmium tetroxide, numerous electron lucent vesicles and canaliculi were distributed throughout the cytoplasm. As ruthenium red-positive reaction product was observed on the inner surface of the vesicles and canaliculi, these are defined as the SCCS of carp thrombocytes. In the stereo-pair of the photographs of thick sectioned specimens and the plastic reconstruction of serially sectioned thrombocytes, we succeeded in finding the whole structure of the SCCS which is composed of numerous anastomosing canaliculi. Scanning electron micrographs revealed many crater-like depressions throughout the cell surface which seem to be the openings of the SCCS.


Effects of stimulation and rest on the ultrastructure of the excitatory neuromuscular junctions of Locusta migratoria L.

The terminals of the fast axon on extensor tibiae muscle fibres of Locusta were examined in untreated nerve-muscle preparations and in preparations stimulated electrically at frequencies varying from 0.5 to 100 Hz. The ultrastructure of the terminals in preparations stimulated at the lower range of these frequencies, which induce twitch contractions of the muscles, is similar to that of the controls. Stimulation at the higher frequencies induced tetanic muscle responses and rapid fatigue of the muscles after which they would not respond again to high frequency stimulation for about 1 h. This loss and recovery of the responses of the muscles is correlated with changes in the ultrastructural appearance of the terminals, in particular in the number and shape of the synaptic vesicles. The ultrastructure of these "recovering" axon terminals closely resembles that of the controls.


Changes in the distribution and size of synaptic vesicles in neuromuscular junctions of Locusta migratoria after stimulation and rest.

The distribution and size of synaptic vesicles in excitatory terminals of the extensor tibiae muscle were determined after stimulation at frequencies varying from 0.5 to 100 Hz and after subsequent rest. Only in preparations stimulated at the higher frequencies do these parameters differ from those in the controls. The synaptic vesicles in the nonsynaptic areas of these terminals are depleted in number, and the remaining vesicles are reduced in size. These effects are reversed after a 1 h rest.


Glutamate uptake after stimulation-induced depletion of vesicle numbers in neuromuscular junctions of Locusta migratoria L.

The distribution of radioactivity at branches and terminals of the fast axon in extensor tibiae muscle incubated in the radiolabelled putative neurotransmitter L-glutamate was determined by electron microscopic autoradiography. Quantitative analysis of the distribution of silver grains at the axon branches and terminals in preparations stimulated at a low frequency shows that most of the radioactivity is present in the glial cells. In preparations stimulated to the point of fatigue substantial radioactivity is present in both the glial cells and the axoplasm of the terminals. It is suggested that the uptake of L-glutamate into the axoplasm of the terminals is correlated with the depletion and recovery of vesicle numbers after stimulation.


In vitro differentiation of hypothalamic magnocellular neurons of guinea pigs.

The development of neurophysin-oxytocin and neurophysin-vasopressin containing neurons of the guinea pig was studied in vitro. Supraoptic (SO) and paraventricular (PV) nuclei were explanted from guinea pig foetuses at the 40th day of gestation and cultured in Maximov slides for nearly fifty days. The cultures were observed daily under a phase-contrast microscope. Explants were fixed every five days for observation with the electron microscope. At the time of explantation, magnocellular neurons were still immature. They acquired the morphologic characteristics of mature neurons, with axosomatic synapses, after about 10 days in vitro. After 15-20 days in vitro, they contained in addition neurosecretory granules (NSG), first in the Golgi region, then also dispersed in the cytoplasm. In the oldest culture (45-50 days), signs of granulolysis were regularly found. It appears that magnocellular neurosecretory neurons are able to differentiate in vitro from a primitive state in the absence of specific stimulation.


Ultrastructural development of the neurohemal organ joined to the ecdysial gland after imaginal moulting in the male isopod Sphaeroma serratum Fab. (Crustacea Flabellifera).

The present ultrastructural study deals with the lateral cephalic nerve plexus of Sphaeroma serratum, a neurohemal organ joined to the Y organ (ecdysial gland). This plexus acts as a storage centre for neurosecretory products from two sources: the two autochtonous cells (plexus cells) within the plexus itself, and the neurosecretory cells in various parts of the central nervous system, particulary the "mandibular ganglion" (A-cells). In prepuberal animals, plexus cells and subesophageal A-cells produce neurosecretory granules of two types measuring 1550 +/- 50 A and 1570 +/- 40 A respectively. Five categories of axon terminals were distinguished in the plexus. The granules found in two of these terminal types are believed to come from the plexus cells and from the "mandibular ganglion" A-cells. Cessation of production of neurosee plexus with concomitant depletion and disappearance of different granule categories. The first axon terminals affected by this process are the two categories containing granules originating in the plexus and "mandibular ganglion" A-cells. Degeneration of the ecdysial gland in male Sphaeroma serratum might be connected with the cessation of granule formation in these two types of cell.


Ontogeny and distribution of certain oendocrine cells in the human fetal large intestine. Histochemical and immunocytochemical studies.

In 9 fetuses, 9 to 24 weeks-old, the occurrence and relative distribution of argentaffin cells, as well as of cells immunoreactive to somatostatin (SRIF), glucagon-like polypeptide (GLI), pancreatic polypeptide (PP) and substance P (SP) were studied in five segments of the colon (appendix, cecum, ascending colon, descending colon, and rectosigmoid). For each colonic segment, data concerned with the occurrence of endocrine cells were expressed either as mean absolute numbers of specific cells per entire mucosal section, or as cell densities per mm3 of mucosa after calculation of the mucosal volume of the sections. Argentaffin, GLI, SRIF and PP immunoreactive cells are all present in relatively large numbers, scattered along the entire length of the colonic mucosa as early as the 9th-10th week of gestation, whereas substance P-containing cells occur sporadically and first appear during the 4th-17th week. Until the 20th week, with progressing embryonic development, an increase was determined in absolute numbers per section of all types of endocrine cells in all segments of the colon. This observation is clearly related to the general growth of the colonic mucosa, since cell densities per mm3 of mucosa do not greatly change or even decrease during gestation. However, it is possible that densities of argentaffin, GLI and BPP cells increase in the appendix around the 14th-17th week of gestation. Between 20th and 24th weeks, absolute numbers of cells per section remain stable or slightly increase, while cell densities tend rather to decrease in all segments. These data demonstrate that some endocrine cells are present very early in the human fetal colon, but their functional significance remains to be elucidated.


Ultrastructure of the antennal sensilla of aphids. I. Coeloconic and placoid sensilla.

An electron microscopical study was made of the coeloconic and placoid sensilla on the antennae of the aphids Aphis pomi, Macrosiphum euphorbiae, Nasonovia ribis-nigri, and Pemphigus bursarius. Scanning electron microscopy revealed some variation in morphology which may be functionally important but is more likely to reflect the evolution of these species. The placoid sensilla were shown by tranwo or three neurons is surrounded by two ensheathing cells. The ciliary regions of the dendrites pass through a vacuole into a cavity between an outer and an inner cuticle where they may be connected to the dendritic branches although such connections were no seen. Small pores (8 nm diameter) partially penetrate the cuticle implying that these sensilla have an olfactory function. They are suggested to be important in host selection by alate aphids. The coeloconic sensilla are poreless pegs with nonsensory cuticular projections at their tips. The distal portions of their dendrites contain densely packed microtubules and the cellular arrangement of the sensila is similar to that of the placoid sensilla. It is suggest that they may function as thermoreceptors.


Normal and experimentally induced lysosomal activity in the larval fat body of Calliphora erythrocephala Meigen.

Acid phosphatase activity was demonstrated by EM-cytochemistry in 4 day old third instar larvae of the fly Calliphora erythrocephala Meigen, but not in younger stages. During larval development, the activity increased, reaching a maximum at the onset of pupariation. The reaction product was localized in Golgi vesicles and sacculi, in vacuoles and in protein granules of varying size and composition, confirming the autophagic character of the protein granules. Throughout larval development, the reaction product was restricted to membrane-bound structures and no indications of "free" cytoplasmic activity that might be related to cytolysis were found. Enzyme activity could be evoked by transplanting inactive fat body lobes into host larvae of a later developmental stage. High enzyme activity was induced in these transplants within 18 h. The sites of activity were roughly the same, but a portion of the activity in the transplants was found in the vacuoles. The induction could be inhibited by cyclohexamide.


Quantitative radioautographic light and electron microscopic analysis of the localization of monoamines in the median eminence of the rat. I. Catecholamines.

By means of light and electron microscopic radioautography a quantitative study of the regional distribution of catecholamines in the median eminence of the rat was carried out. One hour after intraventricular injection of 3H-dopamine the highest radioautographic reaction was recorded in the external zone, especially in the lateral palisade zone where many neurosecretory terminals are separated from the basal lamina of the portal pericapillary space by a glial "cuff". This area showed the highest percentage (52%) of labelled catecholamine containing neurosecretory terminals as well as the maximal silver grain density per one terminal. In the medial palisade zone where direct neurovascular contacts with the capillary loops prevail, only 27 per cent of neurosecretory terminals were found to harbour tritiated dopamine. On the average 35 per cent of neurosecretory terminals in the median eminence of the rat contain catecholamines (both dopamine and noradrenaline). Pretreatment of animals with recretory terminals as well as grain density over terminals were decreased in both the medial and lateral palisade zones, although to a lesser degree in the latter. The site of origin of catecholamine fibers as well as the mode of catecholamine action at the level of the median eminence are discussed.


The osteoclast-endothelium interface during bone resorption in the femurs of young rabbits.

The morphological between the osteoclasts at the endosteal surface of two-week-old rabbit femurs and the endothelium of vascular channels of the bone marrow was examined. Light microscopy revealed that 85% of the osteoclasts make direct contact with the endothelial cells. The ultrastructure of this osteoclast-endothelium interface shows that the osteoclast has specialized processes which reach towards the endothelial cells coming into proximity with them. On rare occasions, specialized junctions between these processes and the endothelial cells are noted.


In vivo production of the nucleolar channel system in post menopausal endometrium.

Endometrial biopsies from seven postmenopausal women on hormone replacement therapy have been examined for the presence of the unique nuclear structure, the nucleolar channel system. Its identification in five of the patients has demonstrated that the nucleolar channel system can be produced by an appropriate oestrogen and progestagen treatment and is not otherwise dependent on ovulation.


A new and unusual type of transport vesicle.

The adventitial cells surrounding the spermatheca of the reproductive system of Sonorella santaritana (Mollusa: Gastropoda) appear to have an unusual system of vesicles. Electron micrographs of the membranes forming these vesicles show that they have multiple openings to the cell's exterior and that each opening has "pore complex". In addition, secondary vesicles appear to be generated by the primary vesicles. Evidence is presented suggesting that these vesicles represent a previously unreported membrane transport system.


Ultrastructural evidence for disuse atrophy in insect skeletal muscle.

The changes which occur in the ultrastruct of the mesothoracic retractor unguis muscle of the cockroach Periplaneta americana as a result of disuse are described. Breakdown of myofibrils, sarcoplasmic reticulum, and mitochondria are all marked, this degeneration only being apparent 9 weeks after the operation.


Separation of RNA transcription and processing activities from X. laevis germinal vesicles.

A procedure suitable for en masse preparation of germinal vesicles (GV) from X.laevis oocytes (Scalenghe et al., 1978) has been adapted for studies of transcription. Extracts from GV contain activities for transcription of tRNA genes and for processing the transcription product. The two activities have been separated by column chromatography. One fraction allows synthesis of tRNA precursor molecules in the presence of X.laevis RNA polymerase III. Another fraction contains the activity that cuts and splices those precursors which contain an intervening sequence. Transcription occurs faithfully on linear DNA fragments.


Fibronectin: a chromatin-associated protein?

We have previously reported that chromatin preparations from human cultured fibroblasts contain a single homologous serum protein. In this paper we present evidence, based on immunological identity and physicochemical properties, that this serum protein is fibronectin. Furthermore, using a radioimmunoassay system, we have estimated that fibronectin represents about 0.7% of the total protein in both chromatin preparations and whole fibroblasts. Using a nitrocellulose filter assay system, we also show that fibronectin is a DNA-binding protein having an equilibrium constant of 4.6 x 10(-6) M. Equilibrium competition experiments have demonstrated that fibronectin has the ability to differentiate among nucleotides, indicating that fibronectin-DNA interaction is at least partially specific, and that a minimum polymer length of 12-18 nucleotides is required for effective binding to occur. Fibronectin has been isolated readily from plasma using DNA-affinity chromatography. We do not have direct evidence that fibronectin is an actual nonhistone chromosomal protein, but fibronectin is a DNA-binding protein (at least under in vitro assay conditions) and appears to be a normal constituent of chromatin as chromatin is currently isolated from cell nuclei.


Purification and characterization of regenerating mouse L929 karyoplasts.

Within 72-96 hr after preparation, about 10% of the karyoplasts made from mouse L929 cells regenerated to reform whole viable cells. As soon as 30 hr after preparation, however, nearly all of the remaining 90% of karyoplasts were dead. By separating living and dead karyoplasts at 30 hr, therefore, that fraction destined to complete regeneration was effectively purified. Complete separation was accomplished by sedimentation through Ficoll-paque (Pharmacia), a patented preparation originally developed for the separation of monocytes from whole blood. With the addition of this technique to the previously reported purification scheme for karyoplasts, various biochemical and morphological studies were attempted. Of particular importance are results indicating that karyoplasts that regenerate do not initially contain any more cytoplasm than the average karyoplasts in a preparation--that is, about 10% of the cytoplasm within a whole cell. Electron microscopy of karyoplasts immediately after preparation indicated an unequal partitioning of cytoplasmic organelles at the time of enucleation. For example, karyoplasts initially contain about 11.4% of the mitochondrial volume of whole cells, but only 2.9% of the Golgi apparatus. The size of the karyoplasts and the volume occupied by a variety of organelles was followed throughout the process of regeneration. Although there was an approximately linear increase in the diameter of regenerating karyoplasts, there appeared not to be a simple concordant increase in the volume occupied by all cellular organelles. An extensive investigation was performed to determine whether or not karyoplasts contained centrioles. Immediately after enucleation, 15,000 random thin sections through karyoplasts, which represented about 100 complete bodies, were examined for the presence or absence of centrioles. No centrioles were observed. Examination of the cytoplasts revealed that they contained a sufficient number of centrioles to account for all of the centrioles that were present in the whole cells before enucleation. Centrioles were first detected in karyoplasts in 24 hr after preparation, about the same time that karyoplasts regained the ability to adhere to the surface of tissue culture dishes. At this time, however, the average karyoplast had less than one centriole. By 72 hr, the regenerated karyoplasts had approximately the same number of centrioles as whole cells.


The effect of avian retroviruses on limb bud chondrogenesis in vitro.

Mesenchymal cells isolated from stage 24 embryonic chicken limb buds were infected with the temperature-sensitive transformation mutants of Rous sarcoma virus tsNY68, tsNY10 and tsLA25 at the nonpermissive temperature for transformation (41 degrees C). Virus infection greatly inhibited subsequent limb bud chondrogenesis under nontransforming conditions, as indicated by a reduction in the rate of 35SO4 incorporation into cell-associated proteoglycans. The inhibition of chondrogenesis was directly related to the percentage of cells infected with tsNY68 at 41 degrees C. The observed inhibition of chondrogenesis was independent of src gene expression since this effect was also caused by many viruses which lack the src gene, including the leukosis viruses RAV-1, RAV-2 and MAV-2(0); the src deletion mutant RSVtd107; and the reticuloendotheliosis viruses REV-T and SNV. Infection of mesenchymal cells with tsNY68 under nontransforming conditions did not cause changes in parameters such as the rate of thymidine incorporation, total cell DNA and total cell protein. Infection with tsNY68 at 41 degrees C resulted in altered kinetics of 35SO4 incorporation into cell-associated proteoglycans and a corresponding reduction in 35SO4-labeled proteoglycans extracted from the cell layer. There were no apparent quantitative effects on the rate of accumulation of proteoglycans in the culture medium. The proteoglycans extracted from the cells and the collected medium of tsNY68-infected cultures were smaller than those of uninfected cultures, as shown by agarose gel chromatography.


Tumor antigens of human Ad5 in transformed cells and in cells infected with transformation-defective host-range mutants.

We have studied the polypeptides associated with the expression of the transforming region of the Ad5 genome by immunoprecipitating antigens (using the double antibody and protein A-Sepharose techniques) from cells infected with wild-type (wt) Ad5 or transformation-defective host range (hr) mutants and from cells transformed by Ad5. Three different antisera were used: P antiserum specific for early viral products (Russell et al., 1967) and two different hamster tumor antisera. Immunoprecipitation of antigens from wt-infected KB cells followed by SDS-polyacrylamide gel electrophoresis of precipitated proteins revealed that a major polypeptide having a molecular weight of approximately 58,000 was detected with all three antisera and with both the double antibody and the protein A-Sepharose techniques, while P antiserum also precipitated polypeptides of molecular weights 72,000, 67,000 and 44,000, which probably represent the DNA binding protein and related polypeptides, respectively. With the double antibody technique, in addition to the proteins mentioned above, P antiserum and the hamster tumor antisera precipitated a 10,500 dalton polypeptide which was not detected when the protein A-Sepharose procedure was used. Using either the double antibody or the protein A-Sepharose technique, we found that hr mutants from complementation group II failed to induce the synthesis of the 58,000 dalton protein, whereas mutants from complementation group I produced normal or near normal amounts. Using the double antibody technique, we found that the 10,500 dalton protein was absent or made in reduced amounts by group I mutants. A 58,000 dalton protein was detected in a number of different Ad5-transformed cell lines, including the 293 human line, the 14b hamster line and several transformed rat cell lines. This observation and the fact that transformation negative group II mutants fail to induce the synthesis of a 58,000 dalton polypeptide suggest that this protein is one of the Ad5-specific products necessary for cell transformation.


Molecular structure and flanking nucleotide sequences of the natural chicken ovomucoid gene.

Five independent clones containing the natural chicken ovomucoid gene have been isolated from a chicken gene library. One of these clones, CL21, contains the complete ovomucoid gene and includes more than 3 kb of DNA sequences flanking both termini of the gene. Restriction endonuclease mapping, electron microscopy and direct DNA sequencing analyses of this clone have revealed that the ovomucoid gene is 5.6 kb long and codes for a messenger RNA of 821 nucleotides. The structural gene sequence coding Ifor the mature messenger RNA is split into at least eight segments by a minimum of seven intervening sequences of various sizes. The shortest structural gene segment is only 20 nucleotides long. All seven intervening sequences are located within the peptide coding region of the gene, and the sequences at the 5' and 3' untranslated regions of the mRNA are not interrupted by intervening sequences. The DNA sequences of the regions flanking the 5' and 3' termini of the gene have been determined. Thirty nucleotides before the start of the messenger RNA coding sequence is the heptanucleotide TATATAT, which is also present in a similar location relative to the chicken ovalbumin gene and other unique sequence eucaryotic genes. This sequence resembles that of the Pribnow box in procaryotic genes where a promoter function has been implicated. Seven nucleotides past the 3' end of the gene is the tetranucleotide TTGT, a sequence found to be present at identical locations as either TTTT or TTGT in other eucaryotic genes that have been sequenced. These conserved DNA sequences flanking eucaryotic genes may serve some regulator function in the expression of these genes.


Nonallelic histone gene clusters of individual sea urchins (Lytechinus pictus): polarity and gene organization.

We have analyzed the histone genes from the sea urchin Lytechinus pictus. Examination of native DNA from individuals reveals four major Eco RI restriction endonuclease histone gene DNA fragments which have been labeled A (6.0 kb), B (4.1 kb), C (3.1kb) and D (1.2 kb). The fragments A, B and C have been cloned into E. coli plasmids (pLpA, pLpB and pLpC). These histone gene fragments display length and sequence heterogeneity in different individuals. The plasmid pLpA contains the coding regions for H1, H4, H2B and H3 histones, and we determined that the DNA fragment D is tandem to A in native DNA and that it contains the H2A gene. The plasmids pLpB and pLpC contain the histone genes H2A-H1-H4 and H2B-H3, respectively, and together contain the sequences for the five major histones. Restriction analysis of native L. pictus DNA reveals that B and C are tandem to each other but not intermingled with the A--D-type repeat units, and are thus in separate clusters with a repeat length of 7.2 kb. Since the two cluster types do not segregate, they are not alleles. Hybridization of histone mRNA to exonuclease III-digested linear DNA demonstrated an identical polarity of the histone genes in the A--D- and B--C-type repeat units. This result revealed that the L. pictus histone genes have a polarity which is the same as other sea urchin histone genes examined to date--that is, 3' H1-H4-H2B-H3-H2A 5'. Restriction endonuclease cleavage patterns of the cloned segments indicate that considerable sequence heterogeneity exists between the two types of histone gene repeat units.