The nucleotide sequence of a methionine tRNA which functions in protein elongation in mouse myeloma cells.

The major form of methionine tRNA operational in the elongation of protein synthesis in mouse myeloma cells was purufied from these cells after they had been cultured in the presence of [32P]-phosphate. This [32P]tRNA4-Met species was then digested with T1 RNase or pancreatic RNase so as to obtain both complete and partial RNase digestion products. The nucleotide sequences of these fragments were analysed to enable the derivation of the complete primary structure of this tRNA. tRNA4-Met of mouse myeloma cells is 76 nucleotides in length and contains 15 modified nucleotides. It is the only tRNA yet sequenced which has been found to possess the minor nucleoside 2-methylguanosine (m2G) within the amino acid (a) stem, and also to have an anticodon (c) stem of only 4 and not 5 base-pairs. The loop IV sequence of eukaryotic initiator methionine tRNA (tRNAf-Met) species, -A-U-C-G-m1A-A-A-, IS NOT FOUND IN TRNA4-Met and is therefore absent from at least one of the methionine tRNAs functioning in polypeptide elongation in mammalian cells. This is consistent with the suggested importance of this loop structure in the initiator function of tRNAf-Met in eukaryotic organisms. Three distinct regions of the tRNA cloverleaf, the (b) stem, the anticodon loop (loop II), and loop III, are substantially conserved in structure between tRNAf-Met and tRNA4-Met of mouse myeloma cells. These regions of the structures of mammalian methionine tRNAs probably do not determine whether a certain tRNA-Met will function in the initiation or elongation of protein synthesis, although they might be important in tRNA-Met recognition if the different cytoplasmic tRNA-Met species of mammalian cells are aminoacylated by a single activating enzyme.


Light chain type ratio of IgA-producing cells in human jejunal biopsies.

As part of an investigation on a possible relationship between the serum IgA and the immunoglobulins synthesized by the plasma cells in the intestinal mucosa, immunoglobulin-producing cells in human jejunal biopsies were characterized by class and type of intracellular immunoglobulins. In biopsy Specimens from 22 patients, with various diagnoses except multiple myeloma, the average percentage of IgA-producing cells was 83 percent, that of IgG-producing cells 5 percent and that of IgM-producing cells 12 percent, with a wide range for individual patients. For the IgA-producing cells the kappa/lambda ratio was determined and the average ratio was found to be 63 : 37, within a very limited range for individual patients. There was no correlation between the relative number of IgA-producing cells in the biopsy specimens and the IgA concentration in the serum. Additionally biopsy specimens from 3 patients with a monoclonal immunoglobulin-A component in their serum were studied. In one of those there was a remarkable shift in the kappa/lambda ratio, indicating that the light chain distribution of the intestinal IgA plasma cells was affected by the lympho-proliferative process.


Narcotic withdrawal like mouse jumping produced by amphetamine and L-DOPA.

Upward jumping in mice that resembled the narcotic-withdrawal syndrome was produced by a combination of amphetamine (4 mg/kg) and L-DOPA (400 mg/kg) administration. Neither drug alone caused that jumping. Pretreatment with haloperidol (0.16 mg/kg) or pimozide (0.08 mg/kg) but not with phentolamine (10mg/kg) effectively blocked amphetamine-dopa jumping. After DOPA there was an increase in the brain levels of DOPA, dopamine and norepinephrine. Amphetamine, ineffective in itself, enhanced DOPA-induced elevation of brain DOPA and dopamine without affecting brain norepinephrine levels.


Comparison of structural and stereoisomers of apomorphine on stereotyped behavior of the rat.

N-n-propylnorapomorphine (NPA) is 35 times more potent than apomorphine (APO) in producing stereotyped behavior in rats. The effect of NPA is blocked by perphenazine but unaltered by alpha-methyltyrosine pretreatment and is accompanied by a decrease in central dopamine turnover. The activity of APO and NPA appears to be primarily in the (-)-isomer, and is diminished but not lost by removal of either hydroxyl group from the catechol ring system.


Effects of clonidine on morphine withdrawal signs in the rat.

The influence of clonidine on the naloxone-induced withdrawal signs, escape attempts and precipitated shakes, was studied in morphine-dependent rats. Clonidine injected i.p. or intraventricularly (i. vent.) inhibited precipitated shakes and potentiated escape attempts induced by naloxone in morphine-dependent rats. Under pentobarbital anesthesia, precipitated shakes and ice water-induced wet shakes were inhibited by clonidine and norepinephrine. Clonidine injected i. vent. reduced body temperatures in morphine-dependent rats but not in placebo pellet-implanted rats. We suggest that clonidine modulates morphine withdrawal signs by potentiating the behavior associated with heat dissipation (escape attempts) and inhibiting the behavior associated with heat gain mechanisms (precipitated shakes). These effects may occur via stimulation of central noradrenergic mechanisms.


The effect of tea on iron absorption.

The effect of tea on iron absorption was studied in human volunteers. Absorption from solutions of FeCl3 and FeSO4, bread, a meal of rice with potato and onion soup, and uncooked haemoglobin was inhibited whether ascorbic acid was present or not. No inhibition was noted if the haemoglobin was cooked. The effect on the absorption of non-haem iron was ascribed to the formation of insoluble iron tannate complexes. Drinking tannin-containing beverages such as tea with meals may contribute to the pathogenesis of iron deficiency if the diet consists largely of vegetable foodstuffs.


The immune response in stationary suspension cultures containing different numbers of cells. The surface density effect.

Correlation between the number of dissociated spleen cells, incubated with antigen in a modified Mishell and Dutton system, and the number of antibody-forming cells (AFC) produced as a result of incubation has been studies in mice of C57Bl/6 strain. It has been shown that when suspension densities are increased 2- to 4-fold, the number of AFC formed is very often reduced 10- to 100-fold, although the percentage of viable cells recovered at the end of incubation is not significantly diminished. The observed reduction of AFC formation in cultures containing increased numbers of cells, designated here the surface density effect, was found to be expressed more by spleen cells of unimmunized than of immunized mice. Inhibition was dependent on the thickness of the cell layer formed on the bottom of the incubation vessel (cells per square centimeter), rather than on the cell: volume ratio of cultures. The effect was not due to a deficit of antigen or nutrition and could not be reproduced by adding of incubation media conditioned by dense cultures. It was determined not by impairment of clone induction but by inhibition of subsequent proliferation. This suppression is reversible and can be reversed by decreasing the cell density, even after 3 days of culture.


Specific effect of neuraminidase on blastogenic response of sensitized lymphocytes.

The blastogenic response of sensitized lymphocytes from guinea-pigs to 'de novo' antigens (KLH, HCH and PPD) was ehhanced by BCN treatment in twenty-one of twenty-three instances. In contrast, no effect of VCN on nonsensitized guinea-pig lymphocyte response to these antigens, or to mumps antigen, was noted in any of thirty-four instances, These findings indicate that the enhancement effect of VCN is specific for sensitized lymphocytes. Heating VCN at 100 degrees for 10 minutes completely abolished the enhancement effect on the lymphocyte response. VCN treatment did not change the kinetics of antigen-induced blastogenesis. The increased lymphocyte response could probably be related to unmasking of the antigen receptor sites of the cells, resulting in increased antigen uptake, following the VCN treatment.


Inhibition of streptococcal attachment to receptors on human buccal epithelial cells by antigenically similar salivary glycoproteins.

Preparations of salivary glycoproteins inhibited the attachment of certain indigenous oral streptococci to human buccal epithelial cells and fostered the desorption of previously attached bacteria. The adherence-inhibiting and desorptive activities of the glycoproteins correlated with their ability to aggregate these organisms. Pretreatment of glycoprotein preparations with certain blood group antisera impaired their adherence-inhibiting effect, suggesting that components with blood group substance reactivity were involved. Pretreatment of buccal epithelial cells with certain blood group antisera or concanavalin A masked the receptors associated with the attachment of Streptococcus sanguis SG1. The association of blood-group-reactive substances with the receptors involved in bacterial attachment may provide a basis for understanding the distinct specificities that bacteria exhibit for attaching to different tissues, organs, and hosts. Antiserum raised in rabbits to human epithelial cells also exhibited receptor-masking activity, and absorption of this serum with homologous salivary glycoproteins removed the antibodies responsible. These observations indicate that some salivary glycoproteins are antigenically similar to components on the epithelial cell surfaces they bathe. It is suggested that by mimicking the receptors present on epithelial cells, the mucinous glycoproteins of secretions may competitively inhibit the sorption of infectious agents and facilitate their removal after they are attached. These activities help to explain how mucinous glycoproteins augment the cleansing action of secretions.


Evaluation of a live, attenuated recombinant influenza vaccine in high school children.

A live, attenuated, recombinant influenza vaccine (Alice strain) administered intranasally was evaluated in high school students and compared with intranasal placebo and subcutaneous, inactivated, bivalent influenza vaccine. The Alice strain was antigenic, increasing the geometric mean titer (GMT) from a prestudy level of 30.2 to a postvaccine level of 189.6. The inactivated vaccine increased the GMT from 32.9 to 361.8. There was no increase in the GMT among the placebo recipients. The Alice strain produced little reaction. With an antigenic, safe, acceptable, live, attenuated influenza vaccine available, immunization on a widespread basis should be considered.


Effect of administered human interferon on experimental rabies in monkeys.

Cynomolgus monkeys infected with rabies virus were protected by repeated intramuscular administration of human leukocyte interferon beginning 24 h after infection.


Effect of cyclophosphamide on infections in mice caused by virulent and avirulent strains of influenza virus.

Induced immunosuppression with the drug cyclophosphamide was shown to convert the relatively harmless infection with an avirulent strain of Kunz influenza virus into a fatal pneumonic illness. The drug was also shown to increase the mortality of mice infected with low concentrations of a virulent variant of this strain, but it delayed the time of death of mice that were infected with high concentrations ofthe same variant. The probable roles of immune and inflammatory mechanisms in recovery from primary influenza virus infections are discussed.


Immunoglobulin E antibody formation in response to homologous rabbit albumin heavily substituted with dinitrophenol: effect of adjuvant.

Although much progess has been made in the detection and characterization of homocytotropic antibodies, identification of the factors which control their synthesis remains to be determined. To assess the influence of different adjuvants on anti-dinitrophenol (DNP) immunoglobulin E (IgE) antibody responses, rabbits were immunized with adjuvant plus homologous albumin (HRA) heavily substituted with DNP (DNP30-HRA). This antigen in rabbits has a B cell-reactive determinant (DNP) and weak non-B cell-reactive determinants (new antigenic determinants) which sensitize rabbits for delayed-type hypersensitivity reactions to DNP30-HRA. It was postulated that the anti-DNP IgE response to DNP30-HRA could be regulated if the immunogenicity of the weak non-B cell-reactive determinants (new antigenic determinants) in DNP30-HRA could be manipulated by adjuvants and dosage. Complete Freund adjuvant and incomplete Freund adjuvant increased the immunogenicity of the new antigenic determinants in DNP30-HRA (10 mg) much more than did alum. However, equivalent primary anti-DNP IgE responses were made by all rabbits sensitized with this dose, regardless of the adjuvant used. Larger doses of DNP30-HRA (25 mg) in alum sensitized rabbits for strong delayed-type hypersensitivity reactions to DNP30-HRA and also elicited enhanced and persistent primary anti-DNP IgE responses. Enhanced but transient primary anti-DNP IgE responses were elicited by 25 mg of DNP30-HRA in incomplete Freund adjuvant. In contrast, no primary anti-DNP IgE responses were made to 25 mg of DNP30-HRA in complete Freund adjuvant. Regardless of the adjuvant or dosage used for primary immunization, no secondary anti-DNP IgE responses to DNP30-HRA were detected.


Environmental modification of western equine encephalomyelitis infection in the snowshoe hare (Lepus americanus).

The snowshoe hare (Lepus americanus) could be infected with western equine encephalomyelitis (WEE) virus and produce a viremia. Furthermore, viremia in hares exposed to variable climatic conditions differed significantly from viremias seen in the control animals held at constant temperatures. The viremia duration and titer were increased in animals subjected to fluctuating temperature and humidity. The time of onset of viremia was accelerated. Antibody response also increased in animals exposed to varying temperatures when compared with controls held at constant temperature and humidity. Snowshoe hares were studied at two distinct seasonal periods: winter, before reproductive activity; and summer, during reproductive midseason. Winter animals experienced greater viremia than did summer hares when exposed to fluctuating temperatures, suggesting a seasonality in the hare's susceptibility to host modification by environmental influences. These findings implicate the snowshoe hare as a possible mammalian amplifying host for WEE virus in the boreal forest.


Ontogeny of spontaneous rosette-forming cells in the chicken. With special reference to the bursa of Fabricius.

Cells forming rosettes (RFC) with sheep erythrocytes (SRBC) and rabbit erythrocytes (RRBC) were studied during the ontogeny of the bursa of Fabricius of the chicken. The frequency of SRBC-RFC was low but significant in the bursa of 15-day-old embryos, and increased therafter in an approximately linear fashion with the age of the bursa donor until at least in 43-day-old chickens. The total number of SRBC-RFC per bursa increased throughout the ontogeny with no evidence for any abrupt increase after hatch. The mean number of SRBC bound per RFC also increased after hatch. In contrast the frequency of bursal RRBC-RFC was high in 15-day-old embryos, significantly decreased on embryonic day 18, remained low until at least 7 days after hatch and then increased significantly. The total number of RRBC-RFC per bursa in contrast remained relatively constant during the embryonic period and the first week after hatch and thereafter increased markedly. No change in the mean number of RRBC bound per RFC could be demonstrated during the ontogeny. RRBC-RFC were also frequent in the yolk sac, spleen, and thymus of 15-day-old embryos.


Studies on a protamine (galline) from fowl sperm. 2. The amino acid sequences of two components of galline.

Galline, a protamine from rooster sperm nuclei, has already been separated into its components, G-I-G-VIII. The amino acid composition of the homogeneously purified fraction G-I is determined decisively to be Arg11, Ser2, Gly3, Val1 and Tyr2, and the molecular weight is 2,908 as hydrochloride. The complete amino acid sequence was deduced as follows from the results of analyses of the tryptic and chymotryptic peptides: H-Ser-Gly-Gly-Val-Arg-Arg-Arg-Arg-Tyr-Gly-Ser-Arg-Arg-Arg-Arg-Arg-Arg-Arg-Tye-OH. Another purified fraction, G-V, has the amino acid composition, Arg24, Thr1, Ser8, Gly3, Ala2, Pro2 and Tyr2 as described previously, and the molecular weight 6,274 as hydrochloride. The complete amino acid sequence was established by combining analytical results of tryptic, chymotryptic and thermolysin peptides as well as those of carboxypeptidase and leucine aminopeptidase digestion as follows: H-Ala-Arg-Tyr-Arg-Ser-Gly-Arg-Ser-Arg-Ser-Arg-Arg-Thr-Arg-Arg-Arg-Arg-Ser-Pro-Arg-Ser-Arg-Gly-Arg-Ser-Pro-Arg-Arg-Arg-Arg-Ser-Arg-Arg-Arg-Arg-Arg-Tyr-Gly-Ser-Ala-Arg-Arg-OH.


Surgery and prognosis of prehepatic portal hypertension.

Results of surgical treatment of prehepatic portal hypertension during the past 15 years were assessed, in addition to routine clinical and laboratory studies, by splenoportography and control mesenteric-venography. One patient survived 14 years. Control angiography of the portal system proved to be most important in assessing the results of surgical treatment, recognizing the cause of late failures and evaluating the course of the disease. All splenectomized patients with general PPH experienced recurrences of hemorrhage which required reoperation. Direct operation on the varices is a favorable procedure, particularly when done as an emergency procedure. Following surgery, early angiographic examination, especially by mesenteric-venography, is mandatory. In cases with poor portal circulation through the liver and massive passage of blood through the varices, PSA should be performed without delay. Portosystemic anastomosis is a selective procedure. Without angiographic study it is contraindicated as an emergency procedure, especially in splenectomized patients.


An unusual epizootic of actinobacillosis in dairy heifers.

Actinobacillosis developed in a group of 52 Holstein-Friesian replacement heifers. They were confined to 4 pens in a barn. Cervical abscesses were first observed by the owner in 1 heifer a month after the heifers were fed chopped haylage that was particularly dry, tough, and stemmy. During the weeks that followed, morbidity reached 73% in heifers given the feed. Calves up to 4 months old were not given the haylage and did not develop the disease. Standard bacteriologic methods were used to identify Actinobacillus lignieresii from exudate of abscesses. A biopsy of superficial granulomatous tissue of the lips revealed fibers thought to be of plant origin. Affected cattle recovered in 3 to 6 months. The lesions of 3 cattle given sodium iodide intravenously and of 4 given streptomycin regressed sooner than those given penicillin or no treatment.


Externship program for large animal clinical education at the University of Minnesota: description and evaluation.

In 1970, the College of Veterinary Medicine at the University of Minnesota started an externship program as part of their large animal clinical education program. The basic idea was to work in cooperation with practitioners, using their practice world as a teaching resource. During the 1973-1974 school year, this program was evaluated by the University of Minnesota Measurement Services Center. In this externship program, senior year students spend 1 or 2 weeks in practice that closely matches each student's career interest, eg, cow-calf, dairy, swine, or zoo. The participating veterinarians are charged with the responsibility of performing as teachers during the field experience and of assisting the student in preparing a seminar topic. This seminar topic is presented in a discussion format during the spring quarter to other externship students, faculty, and attending practitioners. Since 1970, a total of 176 students have taken externships, and every year 15 to 20 group practices have participated. The principal evaluation results were based on questionnaire responses from 36 students and 20 practices during the 1973-1974 academic year. Students and practitioners indicated that the externship had been a beneficial experience for them. Many felt that the period of externship should have been longer. In general, practitioners agreed that students were able to manage most diagnostic situations and manipulative procedures that occurred during the externship. The seminar was judged by students and practitioners to be a valuable part of the program, and faculty who participated in the seminar believed that it made them more aware of field situations facing practicing veterinarians.


Urinary incontinence due to ectopic ureter in a male dog.

Urinary incontinence was associated with an ectopic ureter in a 5-month-old, male Wire Fox Terrier. The dog regained urinary continence after transplantation of the ureter from the urethra into the urinary bladder. Of the 3 reported cases of extopic ureters in male dogs, 2 have been associated with urinary incontinence. These observations do not support the hypothesis that ectopic ureters are more frequently recognized in female than in male dogs because urinary incontinence is more commonly associated with the disorder in female dogs.


Surface carbohydrates of hamster fibroblasts. II. Interaction of hamster NIL cell surfaces with Ricinus communis lectin and concanavalin A as revealed by surface galactosyl label.

When hamster fibroblasts (NIL) were treated with galactose oxidase followed by reduction with tritiated borohydride (GAHMBERG, C. G. AND HAKOMORI, S. (1973) J. Biol. Chem. 248, 4311; STECK, T. L., AND DAWSON, G. (1974) J. Biol. Chem. 249, 2135), two major galactoprotein labels were detected on the cell surface: "galactoprotein a" (apparent molecular weight 200,000) and "galactoprotein b" (apparent molecular weight 130,000). The labeling in galactoprotein a of NIL cells was greatly suppressed by pretreating cells with a high concentration of Ricinus communis lectin or concanavalin A, whereas the label in it was greatly enhanced with a low concentration of the lectins. The label in galactoprotein b of NIL cells was less affected by pretreatment with lectins. In NILpy cells the label in galactoprotein a was absent and the lable in galactoprotein b was enhanced by pretreating cells with lectins at low concentrations, but it was suppressed at high concentrations. The results indicate that NIL cells mainly interact with the lectins through galactoprotein a, whereas NILpy cells interact with the lectins through galacto-protein b. After treatment with lectins, the glycolipids of normal NIL cells, but not NILpy cells, became exposed as evidenced by enhanced labeling, possibly because of "clustering" of glyco-proteins. These results support the view that specific, well defined glycoproteins are the binding sites for lectins, and that these interacting glycoproteins are qualitatively different in normal and transformed cells.


Purification of a fibroblast growth factor from bovine pituitary.

The purification from bovine pituitary gland of a growth factor responsible for the control of animal cell division in tissue culture is reported. This growth factor is a polypeptide of 13,300 molecular weight and is homogeneous when analyzed by polyacrylamide gel electrophoresis, carboxymethyl-Sephadex gradient elution chromatography, and Sephadex G-50 chromatography. The yield of growth factor is 5 mg per kg of pituitary. It is active in stimulating DNA synthesis in 3T3 cells at concentrations as low as 2 times 10-13 M with saturation at 1 times 10-10 M.


Regulation of phospholipid metabolism in differentiating cells from rat brain cerebral hemispheres in culture. I. Uptake and phosphorylation of [U-14C]ethanoloamine and the effect of various inhibitors.

Cultured dissociated cells from rat embryo cerebral hemispheres were incubated with [U-14C]ethanolamine and the resulting cellular labeled products were identified. A highly efficient uptake for ethanolamine with a Km of approximately 8.3 muM was calculated. A rapid labeling of phosphorylethanolamine was observed prior to the appearance of label in lipids. A lag period of 2.5 min for the phosphorylation reaction was observed, followed by an almost linear rate for up to 40 min. After a 1-min incubation, a plateau for free ethanolamine taken up by the cells was established. Respiratory inhibitiors such as cyanide, 2,4-dinitrophenol, and N-ethylmaleimide decreased by the formation of phosphorylethanolamine. However, the amount offree ethanolamine present in the cells increased 1.6-fold after 10 min of incubation with N-ethylmaleimide. 2-Chloroethylamine, a structural analog of ethanolamine, and choline were both competitive inhibitiors with an apparent Ki of 0.1 mM and 0.36 mM, respectively. Incubations of short duration suggest that both compounds affect ethanolamine transport into the cells. Based on these studies it is suggested that ethanolamine transport and the phosphorylation reaction are independent events. Evidence based on studies with hemicholinium-3 and chloroethylamine suggest that ethanolamine uptake may proceed by a pathway independent of either choline or serine uptake.


Regulation of phospholipid metabolism in differentiating cells from rat brain cerebral hemipheres in culture. II. Incorporation of [U-14C]ethanolamine into 1-alkenyl,2-acyl-and 1,2 diacyl-ethanolamine phosphoglycerides.

Cultured dissociated cells from rat embryo cerebral hemisphere incorporate [3H]-and [U-14C]ethanolamine into cellular lipids. Nearly all radioactivity in the lipid fractions is incorporated into 1,2-diacylethanolamine phosphoglycerides and 1-alkenyl,2-acylethanolamine phosphoglycerides (plasmalogen). Kinetic data suggest that the rate of labeling of both ethanolamine phospholipids from the phosphorylethanolamine is similar. A relative increase of the plasmalogen labeling is observed when free ethanolamine is continually present in the medium. The rate of incorporation of label from ethanolamine and phosphorylethanolamine into lipids was measured using a double label technique. Based upon these studies, an independent labeling pattern of the ethanolamine moiety of plasmalogens is suggested. A relative delay for the incorporation of label in plasmalogens could be explained by the presence of a variety of cell types which may differ in their capacity for phospholipid biosynthesis. The rate of incorporation of phosphorylethanolamine into the phosphatidylethanolamine was not affected by the presence of high concentrations of either choline or serine.


Properties of 4-ethenyl and 4-ethynyl analogs of pyridoxal phosphate and their reactions with the apo form of asparatate aminotransferase.

The binding to apoaspartate aminotransferase of analogs of pyridoxal phosphate bearing vinyl, cis- and trans-methylvinyl, and ethynyl groups in place of the fomyl group of the coenzyme has been studied. Details of synthesis of the ethynyl compound are given. The absorption spectra of all of the compounds have been analyzed and pKa values have been determined. The positions of the absorption bands can be related to those of pyridoxine but with bathochromic shifts induced by the ethenyl and ethynyl groups. However, this shift is almost completely lacking for the cis-methylvinyl compound suggesting nonplanarity of the molecule. Binding of the analogs to the apoenzyme is accompanied by a strong bathochromic shift which, from a study of solvent effects on the free analogs, appears to indicate a hydrophobic environment on the enzyme. Nevertheless, the analogs are bound as dipolar ions exclusively. Binding is accompanied by a distinct perturbation of the protein spectrum in the aromatic region. An effect on the spectrum of 1 or more tryptophan residues is indicated. Bands of the bound analogs exhibit positive circular dichroism except for that of the 4-vinyl analog. The 4-ethynyl analog reacts in a more complex way, giving at least two successive products in addition to the initial complex. The final product is reducible by sodium borohydride, is released from the enzyme by boiling, and appears to have the properties of a Schiff base. We postulate that the addition of an amino group of the enzyme to the ethynyl group is followed by tautomeric rearrangement to a Schiff base in which the ring is in a p-quinonoid structure.


Purification and subunit structure of deoxyribonucleic acid-dependent ribonucleic acid polymerase II from the mouse plasmacytoma, MOPC 315.

DNA-dependent RNA polymerase II was purified from the mouse plasmacytoma, MOPC 315. Soluble enzyme was obtained from a nucleoplasmic fraction and subjected to chromatography on phosphocellulose, DEAE-cellulose, and DEAE-Sephadex ion exchange resins and was subjected to sedimentation in sucrose density gradients. A chromatographically homogeneous enzyme was obtained which was purified about 25,000-fold relative to whole cell extracts and which had a specific activity (on native DNA) similar to those reported for other purified eukaryotic class II RNA polymerase preparations. Analysis of purified RNA polymerase II by polyacrylamide gel electrophoresis under nondenaturing conditions revealed three protein bands, designated II-O, II-A, and II-B in order of electrophoretic mobility. The subunit compositions of these nondenatured bands were subsequently analyzed by electrophoresis under denaturing conditions. Each enzyme II form contained subunits with molecular weights of 140,000 (II-c), 41,000 (II-d), 30,000 (II-e), 25,000 (II-f), 22,000 (II-g), 20,000 (II-h), and 16,000 (II-i). Molar ratios were unity for all subunits except subunit II-h which had a molar ratio of 2. Each enzyme form was distinguished by its highest molecular weight subunit. II-O contained subunit II-o (molecular weight 240,000), II-A contained subunit II-a (molecular weight 205,000), and II-B contained subunit II-b (molecular weight 170,000). Total molecular weights for II-O, II-A, and II-B were calculated as 554,000, 519,000, and 484,000, respectively. In addition, the number of RNA polymerase II molecules per MOPC 315 tumor cell was calculated to be about 5 times 10-4.


Primary structure of the L chain from a rabbit homogeneous antibody to streptococcal carbohydrate. I. Purification of antibody and sequence determination of peptides from alpha-chymo-tryptic and thermolytic digests.

Primary structural studies have been carried out on the light chain of a homogeneous rabbit antibody to Group C streptococcal carbohydrate. Approximately 20 g of this antibody were obtained by multiple exchange transfusions at the peak of the antibody response. The isolated antibody was homogeneous by several antigenic and chemical criteria. The light chain was isolated and modified, and then digested with alpha-chymotrypsin or thermolysin. The resulting peptides were isolated by gel filtration, paper electrophoresis, and paper chromatography. The amino acid sequences of these peptides were determined by Edman degradation plus dansylation. This supplied sufficient information to assign approximately 90 percent of the residues in the chain. The destruction of tyrosine during acid hydrolysis of peptides which had been eluted from a paper chromatogram was investigated. This destruction is due to inpurities in the paper which contaminate the peptides. Prevention of such destruction can be achieved by predevelopment of the paper with 1 N NH4OH prior to paper chromatography.


Deficient uridine diphosphate-N-acetylglucosamine:glycoprotein N-acetylglucosaminyltransferase activity in a clone of Chinese hamster ovary cells with altered surface glycoproteins.

We have reported the isolation of a clone (termed 15B) of Chinese hamster ovary (CHO) cells which are deficient in certain plant lectin-binding sites and have decreased amounts of sialic acid, galactose, and N-acetylglucosamine in its membranes (Gottlieb et al. (1974) Proc. Natl. Acad. Sci. U.S.A. 71, 1078-1082). This study demonstrates that extracts of 15B cells, in contrast to the parent cell line, do not transfer N-acetylglucosamine residues from UDP-GlcNAc to certain glycopeptide and glycoprotein acceptors containing terminal nonreducing alpha-linked mannose residues. The decreased enzyme activity could not be accounted for by the presence of inhibitors, altered pH, or Mn2+ requirements of the glycosyltransferase or increased N-acetylglucosaminidase activity in the extracts. The finding that the 15B cell extracts have significant but reduced N-acetylglucosaminyltransferase activity toward a degraded orosomucoid acceptor suggests that these cells have a selective loss of one of several specific N-acetylglucosaminyltransferases which are present in the parent CHO cells. The sialyl- and galactosyltransferase activities of 15B and parent CHO cells are comparable. Parent CHO and 15B cells were grown in radioactive glucosamine to label the membrane glycoproteins. Solubilization of these glycoproteins and passage over a Ricinus communis agglutinin I (RCA I) Sepharose affinity column revealed that no labeled 15B glycoprotein material bound, whereas 50 percent of the CHO membrane glycoproteins bound and could be eluted with the haptene lactose, demonstrating that 15B cells are virtually devoid of membrane oligosacharides capable of binding to the RCA I lectin. The 15B membrane glycoproteins exhibited a marked shift toward glycoprotein species of lower molecular weight when examined by gel electrophoresis in sodium dodecyl sulfate. It is proposed that this shift in the mobility of the 15B membrane glycoproteins results from a decreased glycosylation of a number of membrane glycoproteins relative to their counterparts in CHO cells. The deficient N-acetylglucosaminyltransferase activity in 15B cells can account for the decreased glycosylation of the 15B cell membrane glycoproteins.


Antifreeze glycoproteins from an Antarctic fish. Quasi-elastic light scattering studies of the hydrodynamic conformations of antifreeze glycoproteins.

A quasi-elastic light-scattering technique was used to study the hydrodynamic conformations of antifreeze glycoproteins from an Antarctic fish. Antifreeze glycoprotein is composed of repeating units of Ala-Ala-Thr, with each threonine O-linked to a disaccharide, and it exists as several polymers of different numbers of this repeating unit. Molecular weights of the two major active polymers are 10,500 and 17,500 by such methods as centrifugation and osmotic pressure, but smaller than 20 by freezing-point depression. Translational diffusion coefficients at 20 degrees were 8.35 times 10-7 cm2 s-1 and 6.15 times 10-7 cm2 s-1 for the M-r-10,500 and 17,500 polymers, respectively. Measurements at -0.2 degrees in the presence of ice crystals did not indicate any conformational changes that might be related to the lowering of the freezing temperature. Lowering the temperature of these glycoprotein solutions close to temperatures of freezing caused a decrease in the effective hydrodynamic radius of both active and inactive glycoprotein components.


Hydrolysis of diacylglycerols by lipoprotein lipase.

Enantiomeric diacylglycerols were emulsified, mole for mole, with lyso(1-acyl) lecithin and were hydrolyzed with lipoprotein lipase in NH4Cl-beef serum albumin buffer at pH 8.6 after a brief incubation with delipidated rat serum. The enzyme was prepared from lyophilized and dialyzed bovine skim milk in a 4 percent solution. The course of hydrolysis for each set of enantiomers was determined by gas-liquid chromatography of the masses of the diacylglycerols remaining or monoacylglycerols released in the medium between 0 and 15 min. The majority of sets of sn-1,2- and 2,3-diacylglycerols, including an isotope-labeled true enantiomeric set which was assessed by mass spectrometry, demonstrated preference by the enzyme for lipolysis at position 1 but with less specificity than previously was shown in sn-triacylglycerol hydrolysis. The results preclude the possibility that the predominance of sn-2,3-diacylglycerol intermediates during triacylglycerol hydrolysis is due solely to a preferential breakdown of the 1,2-isomers and reinforce the conclusion that lipoprotein lipase is specific for position 1.


Fluoride inhibition of the initiation of protein synthesis in the reticulocyte lysate cell-free system.

KF (30 mM) strongly inhibits polypeptide chain initiation in the reticulocyte lysate cell-free system.. Chain elongation is partially inhibited but proceeds to a significant extent with little initiation of new chains. Polysome breakdown is incomplete after incubations as long as 20 min. Under these conditions deacylated tRNA-Met accumulates in a fraction sedimenting faster than 120 S and thus may be associated with ribosomes bound to mRNA. Incubation of the system with KF results in the accumulation of a complex which can initiate synthesis of polypeptide chains in the presence of aurintricarboxylate; KF thus inhibits a step in initiation after that inhibited by aurintricarboxylate. The accumulation of deacylated tRNA-Met is correlated with the accumulation of the aurintricarboxylate-resistant complex. Both phenomema are dependent on KF and both are inhibited by aurintricarboxylate in the same range of concentrations which inhibit initiation of protein synthesis.


The purification and some properties of electron transfer flavoprotein and general fatty acyl coenzyme A dehydrogenase from pig liver mitochondria.

Electron-transferring flavoprotein (ETF) and acyl dehydrogenases of pig liver mitochondria have been isolated in good yield by a new procedure. ETF and general acyl dehydrogenase appear homogenous, are free of reciprocal contamination, react with neither pyridine nucleotides not cytochrome c, and are completely dependent upon each other for reduction of dichlorophenol indophenol by acyl-CaA substrates. The properties of the present preparation (some of which differ significantly from those previously described) are presented. Sedimentation of ETF in 0.02 M KP-i yields a M-r for the native ETF of 58,00 plus or minus 3,000, whereas sedimentation of reduced and alkylated ETF in guanidine HCl yields a M-r of 26,000. Electrophoresis on sodium dodecyl sulfate gels in the presence or absence of mercaptoethanol gives a M-r of about 27,000 and flavin analysis gives a minimum molecular weight of about the same figure. Thus, ETF appears to contain one flavin (at least 90% FAD, by chromatographic and fluorescence characteristics) per 26,000 M-r, and therefore may be composed of two subunits with one flavin each. Sodium dodecyl sulfate gel electrophoresis of general acyl dehydrogenase in the absence of mercaptoethanol gives a band corresponding to a M-r of 84,000; in the presence of mercaptoethanol a band corresponding to a M-r of 42,000 is found. The minimum molecular weight based on flavin content is 40,500. These data considered in conjunction with previous reports from other laboratories, suggest a structure of four subunits per mol with one flavin per subunit..


Effect of leucine on the temperature sensitive phenotype of a mammalian leucyl-tRNA synthetase mutant.

The concentration of leucine in the growth medium has been found to influence the expression of the temperature sensitive phenotype of a mutant of Chinese hamster ovary cells with an altered leucyl-tRNA synthetase. Plating efficiency and growth studies showed that increasing the leucine concentration allows cells to survive at normally non-permissive high temperatures and conversely decreasing the leucine concentration enhances the adverse effectsof high temperature. A similar but smaller effect was noted with isoleucine. It is suggested that this observation may form the basis of a rapid test, useful in directing the investigation of the lesion in similar mutants to pathways involving specific amino acids.


The early effects of ouabain on potassium metabolism and rate of proliferation of mouse lymphoblasts.

Murine lymphoblasts grown in suspension culture in the presence of ouabain showed a dose dependent and sequential decrease in 86Rb+ (K+ analogue) influx, cellular potassium content, and growth rate. An increase in eosin staining and a decrease in cell number was observed after two hours in the presence of 1 mM ouabain; 1 muM ouabain was without effect on any of the parameters measured. Ouabain inhibition was rapidly and completely reversible at concentrations that were not cytotoxic.


Adaptation of potassium metabolism and restoration of mitosis during prolonged treatment of mouse lymphoblasts with ouabain.

The effects of ouabain on the growth of murine lymphoblasts in vitro have been studied. Exposure of cells to ouabain (0.1 mM) initially inhibited 86Rb+ uptake rate, reduced the intracellular potassium concentration, and decreased population growth rates. Continued exposure to the same ouabain concentration resulted in an increase of 86Rb+ uptake rate, intracellular potassium content and population growth rates to control values (adaptation). When treated cells were resuspended in medium free of ouabain after 12 to 15 hours of ouabain treatment, 86Rb+ uptake rates and intracellular potassium levels exceeded those of untreated cells. Adaptation was inhibited by cycloheximide (3 mug/ml) and by actinomycin D (0.05 mug/ml). Kinetic analysis of transport suggested that while the total capacity of the Na/, K+ transport system increased, the affinity for both the cation (86Rb+) and ouabain decreased.


The effects of ouabain on the cell mitotic cycle of mouse lymphoblasts.

The inhibition of cell proliferation by ouabain has been analyzed with respect to the cell cycle. Three lines of evidence indicate that growth rate is modified by altering to different degrees the rate of progress through stages of the cell cycle: (1) a three hour lag occurs between the time of ouabain addition and the inhibition of proliferation; (2) oubain must be present at least two to four hours prior to the mitotic burst of synchronized cells for inhibition of mitosis to occur; (3) parasynchrony is observed when cells are resuspended in ouabain-free medium after 12 hours of exposure to ouabain. Analysis of the distribution of cells in each of the stages of the cell cycle at various times during ouabain treatment reveals a progressive increase in the fraction of cells in S with a concomitant decrease in the percent of cells in each of the stages. These results indicate that the prolongation of the cell cycle time in the presence of ouabain is due primarily to an S stage block.


The pattern of density dependent growth inhibition in murine fibroblasts.

Observations on the pattern of nuclear incorporation of 3H-TdR in long term (8-day) and short term (3-day) 3T3 cultures with local cell densities between 0.2 times 10-4 and 6.2 times 10-4 cells/cm2 are reported. Contrary to a number of previous studies our observations indicate that density dependent inhibition is exhibited in relatively sparse cultures, commencing at 0.5 times 10-4 cells/cm2. Various possible mechanisms which could have caused the observed pattern of density-dependent regression in labelling index are discussed.


The effect of potassium on the cell membrane potential and the passage of synchronized cells through the cell cycle.

The cell membrane potential of cultured Chinese hamster cells is known to increase at the start of the S phase. The putative role of the cell membrane potential as a regulator of cell proliferation was examined by following the cell cycle traverse of synchronized Chinese hamster cells in the presence or absence of high exogenous levels of potassium. An increase in external potassium levels results in a depressed membrane potential and a reduced rate of cell proliferation. A potassium concentration of 115 mM was used in experiments with synchronized cells since at that level cell proliferation is almost completely halted, recovery of growth is rapid and complete, and the membrane potential is reduced to a level well below that normally found in cells in the G1 phase. A mitotic population was divided into four aliquots and plated in either control medium or medium containing 115 mM K+. Cells placed directly into high K+ medium were retarded in their exit from mitosis and displayed a delayed and abnormal entry into the S phase. If control medium was added after two hours, cell cycle traverse was normal, but delayed by two hours compared to control cells. If the mitotic cells were plated directly into control medium and two hours later were shifted to high K+ medium, the cells entered the S phase in the absence of the normally observed increase in membrane potential and proceeded to the next mitosis normally. It was concluded that the increase in membrane potential observed at the start of the S phase in isolated synchronized cells is not a requirement for the initiation of DNA synthesis. In addition, sensitivity to the high potassium regimen was found at two different times during the cell cycle. In one case, cells were impeded in their transit through mitosis. Such cells displayed an altered chromosome structure which may account for the partial mitotic block. In the second case, synchronized cells displayed a sensitivity to the high potassium regimen in early G1 which appeared to be separate from the block in mitosis and independent of a change in the membrane potential.


Activation and inactivation of genes determining hemoglobin types.20s.

Globin gene switching in sheep and goats has been used as a model system for examining gene expression in differentiating red blood cells. Sheep and goats switch from the synthesis of hemoglobin A to hemoglobin C in response to erythropoietin. The regulatory mechanism producing this switch in hemoglobin types could occur at the cellular, nuclear, or cytoplasmic level. Evidence is presented which suggests that regulation is occurring, in fact, at the nuclear level. Sheep and goat erythroid colonies have been grown in plasma clot culture in order to study the synthesis of individual globin chains. Erythropoietin is required for colony formation. The switch from hemoglobin A to hemoglobin C synthesis requires not only colony formation but also a higher concentration of erythropoietin than is required just for the production of colonies. A cell-free transcriptional system using bone marrow chromatin and mammalian DNA-dependent RNA polymerase has been developed in order to examine the nuclear control mechanisms in more detail.


Vitamin B6 metabolism in chronic alcohol abuse The effect of ethanol oxidation on hepatic pyridoxal 5'-phosphate metabolism.

Individuals with chronic alcohol abuse frequently exhibit lowered plasma levels of pyridoxal 5'-phosphate, the coenzyme form of vitamin B6. Because the liver is the primary source of this coenzyme in plasma and also the principal organ that oxidizes ethanol, the effect of ethanol on hepatic pyridoxal phosphate metabolism was studied in the rat. The chronic feeding of ethanol (36 percent of the total dietary calories) for 6 wk significantly decreased the hepatic pyridoxal phosphate content both in animals given a sufficient amount of vitamin B6 in their diet and in those rendered vitamin B6 deficient. In isolated perfused livers, the addition of 18 mM ethanol lowered the pyridoxal phosphate content of livers from vitamin B6-sufficient animals and deceased the net synthesis of pyridoxal phosphate from pyridoxine by the livers of vitamin B6-deficient animals. Ethanol also diminished the rate of release of pyridoxal phosphate into the perfusate by the livers of vitamin B6-deficient rats. These effects of ethanol, in vitro, were abolished by 4-methyl pyrazole, an inhibitor of alcohol dehydrogenase. Thus the derangement of pyridoxal phosphate metabolism produced by ethanol is dependt upon its oxidation. These data support previous findings whic indicate that acetaldehyde is the responsible agent which acts by accelerating the degradation of intracellular pyridoxal phosphate.


Maternal behavior of mice with cingulate cortical, amygdala, or septal lesions.

Nest building, pup retrieving, and pup survival and growth were evaluated in primiparous control mice and those with cingulate cortical, neocortical, amygdala, or septal lesions. Mice with neocortical or amygdala lesions showed little or no deficits in maternal behavior. Mice with septal lesions were severely impaired in all aspects of maternal care. These mice did not build nests, showed a variety of aberrant behaviors during pup retrieving, and their pups died or gained significantly less weight than those of controls. Mice with cingulate cortical lesions retrieved pups more slowly than controls, and retrieving deficits were correlated with the extent of retrograde degeneration found in the anterior thalamic nuclei.


Factors in the modification by isolation of electroconvulsive shock-produced retrograde amnesia in the rat.

It has been demonstrated that placing rats in a sensory-restricted environment during the electronconvulsive shock- (ECS) retention interval following 1-trial appetitive learning will prevent or eliminate ECS-produced retrograde amnesia. The first study replicated this finding with a 1-trial aversive learning task, indicating that this effect is not task specific. The second study attempted to determine whether illumination or the restricted environment was the crucial factor in this penomenon. Rats placed in the light during the ECS-retention interval, whether restricted or in the colony, demonstrated retrograde amnesia after ECS. However, rats left in the dark during this interval demonstrated little, if any, retention deficit particularly if this condition was combined with sensory isolation. These studies further indicate that manipulation of the general environment of the animal after ECS can alter ECS-produced retention losses.


Amnesic effect of cycloheximide in the mouse mediated by adrenocortical hormones.

The involvement of adrenocortical hormones in the amnesic effect of cycloheximide was examined in mice. Subcutaneous injection of cycloheximide shortly before a training trial of a passive avoidance task resulted in an amnesia of the avoidance response. However, amnesia was absent in the adrenalectomized animals in which cerebral protein synthesis was suppressed by cycloheximide. Injection of corticosteroids antagonized the amnesic effect, most effecively if the steroids were given immediately after training. The influence of the hormonal treatments upon the amnesic effect was not ascribable to a change in general activity level. The amnesic effect of subcutaneously injected cycloheximide appears to be mediated by hormonal deficiency, and not related to suppression of the cerebral protein synthesis.


Suppression of mouse killing and apomorphine-induced social aggression in rats by local anesthesia of the mystacial vibrissae.

Local anesthesia of the facial epidermis can effect a substantial decrease in shock-elicited fighting of paired rats. The present experiments constitute methodological extensions to mouse killing and spontaneous drug-induced social aggression. In the first experiment, known mouse-killing rats were given bilateral lidocaine or placebo injections administered under ether anesthesia. Attack and kill latencies were significantly longer under lidocaine than under placebo; all subjects killed under placebo, whereas a third of all subjects failed to kill on the initial lidocaine test. On subsequent lidocaine testing, latencies decreased and nonkilling rats killed. In a second experiment intense apomorphine-induced conspecific fighting of rats preselected for aggressiveness was markedly reduced following lidocaine anesthesia. The comparative results of both experiments are interpreted in reference to theoretical assertions regarding the import of sensory information in stimulus-bound attack and the typology of central aggression systems.


Competitive fighting in the rat.

Competitive fighting was obtained in pairs of like-sexed laboratory rats by placing a single piece of food into the food hopper following 48 hr. of food deprivation. The fighting was characterized by offensive sideways posture, full aggressive posture, and bite and kick attack. Tests were conducted at 110-120 days of age on pairs of animals that had been housed together since weaning. Fighting was more frequent in pairs consisting of nonlittermates than in pairs of littermates, and it was equally frequent in male and female pairings. Probability of fighting was enhanced by prior experience with food deprivation, and attack was most often initiated by the heavier animal of the pair.


Social position and competition in laboratory rats.

Two experiments with rats as subjects are described, which control for social position, i.e., relative dominance/submission, in an appetitive social learning-performance setting. The results indicate that animals that perform quite effectively when alone exhibit significantly reduced levels of responding when placed into a social environment. The severity of the response decrement is, at least in part, a function of the relative social position of the subjects involved. A dominant male made few responses when paired with another dominant male. Yet, a dominant subject made even fewer responses when paired with a submissive subject, which bar pressed at approximately half the individual level. These findings are interpreted as suggesting that social position, with its accompanying characteristic form of aggression, is an important determinant of performance in a social learning environment.


Gastric secretion as a function of acute and chronic stress in the gastric fistula rat.

In Experiment 1 rats exposed to signaled and unsignaled grid shock secreted more gastric acid after shock stress (chronic stress) for 8 days compared to the first 12 hr. of shock stress (acute stress). However, Experiment 2 indicated that the higher gastric acid values under chronic stress were not significantly greater than prestress baseline values. The results are interpreted to reflect an inhibition of gastric acid secretion as a function of acute stress. During chronic stress this inhibition is followed by a habituation of gastric secretory processes which is observed as a return of secretion volume to baseline levels.


Comparative nasal absorption of allergens in atopic and nonatopic subjects.

Based on sensitization following intranasal antigen administration, previous investigations have suggested greater absorption of allergens through the nasal mucous membranes of atopic than of nonatopic subjects. In this study mucosal absorption was assessed more directly by determining the capacity of allergens applied intranasally to elicit cutaneous Prausnitz-Küstner (P-K) reactions in nonatopic persons as compared with asymptomatic atopic subjects sensitive to other allergens. Two series of reaginic human serum dilutions were injected intracutaneously in recipients backs, and 48 hours later one series was challenged intracutaneously with test allergen. After the responses had been recorded, concentrated allergenic extract was sprayed into the nose and the second series of P-K sites observed for reactivity. Sometimes these P-K sites were rechallenged intracutaneously the following day to determine passive transfer neutralization. Two allergens were studied: bovine ribonuclease (RNase) and peanut extract. Two sera containing peanut reagins and one with RNase antibodies were each used in 10 to 11 atopic and 9 to 11 nonatopic recipients. The atopic group failed to show greater or more rapid absorption of either allergen through the nose based on the highest serum dilution reacting after nasal challenge. the speed of the reaction, the ratio of the titer by nasal challenge to the intracutaneous titer, or passive transfer neutralization. Controls showed that the results were not influenced by systemic absorption of allergen employed for intracutaneous tests. Drinking the amount of peanut extract applied intranasally did not elicit P-K reactions.


Measurement of IgE antibodies by the radioallergosorbent test. I. Technical considerations in the performance of the test.

Since its introduction by Wide, Bennich, and Johansson in 1967, the radioallergosorbent test (RAST) has been increasingly used for measurement of specific IgE antibodies. In this study we have varied the conditions during the performance of the RAST and have investigated the effect of altering: (1) the speed of rotation of tubes, (2) the number of washes in both steps of the test, (3) the length of rotation of tubes, (4) the temperature, (5) the conditions during centrifugation, (6) the quantity of antibody to IgE in the second step of the test, (7) the composition of buffers in the reactions, (8) the type of tube employed in the test, (9) the quantity of antigen employed during the coupling procedure, and, finally, (10) the iodine isotope, 125I or 131I, used to radiolabel anti-IgE. Of these variables the most significant were the quantity of anti-IgE used in the second step of the test and the quantity of antigen used in the coupling procedure. Other variables of importance were the choice of radioiodine, whether the tubes were rotated or not, the type of tube used, and finally the diluent employed.


The dietitian and credentialing.

The meaning and ramifications of credentialing and accreditation have direct and powerful implications for the professional dietitian. There is also intense interest on the part of the public, as it views each profession's role in providing health care, as to the quality and expense ot that care. Each dietitian's analysis of the direction our Association must take in accreditation and credentialing is mandatory to the growth of nutritional care and its responsiveness to the needs of the American people. Issues have been presented and reviewed in this article. Some proposals for change have been suggested. By no means is the issue of accreditation or credentialing static among the health professions. New studies are being started routinely. New ideas and issues are continually being proposed and analyzed. What is good today for the practitioner and the public may be non-functional tomorrow. However, it seems certain that changes are imminent. It is imperative that each member of The American Dietetic Association assume an active role in the decisions that will be made for the future of each of us.


The distribution of uterine glycogen during early pregnancy in the young and senescent golden hamster.

Glycogen distribution in the uterus of young and old hamsters was examined histochemically during the implantation of the embryo. Decidual cells and glycogen first appeared at 96 hours (post-ovulation) in the young animal. Decidualization did not occur in the senescent animal until 108 hours of development and the appearance of glycogen in the antimesometrial stroma was further delayed until 120 hours of development in the aged female. By 132 hours glycogen synthesis in the antimesometrial decidua was similar in both groups. Mesometrial glycogen synthesis in the aged animal continued to lag behind that of the young animal throughout the period investigated. The role of the delayed decidual cell response and the appearance of glycogen as possible causal factors in the observed decreased reproductive output in senescent animals is discussed.


Studies on the inhibition of C56-induced lysis (reactive lysis). VI. Modulation of C56-induced lysis polyanions and polycations.

Multiple polyanions and polycations were tested for their ability to influence formation of EC567 from C56, C7, and sheep erythrocytes. Six of 11 polyanions tested, including polyanethol sulfonate, heparin, and dextran sulfate, inhibited this reaction. By contrast, polycations (five or seven tested), including polybrene, protamine, and polyornithine, potentiated formation of EC567. The inhibition was similar to that previously described for anionic serum factors termed C567-INH, while the potentiation seemed to involve neutralization of serum C567-INH. Thus, this step of the complement attack mechanisms seems amenable to modulation by certain polyelectrolytes, and may thereby be susceptible to pharmacologic manipulation.


Immune precipitation of immunoglobulin producing polysomes from mouse myeloma cells.

MPC-11 myeloma cells synthesizing IgG were labeled in vitro with 3H-uridine and the cell lysates, or purified polysomes treated with rabbit antiserum against the purified MPC-11 protein. The specificity of the immune precipitation was tested by rabbit anti-egg albumin and by precipitation of polysomes from "non-producer" myeloma and HeLa cells. The specific precipitation was 10 to 15% of the total cytoplasmic RNA for the IgG-producing clone of MPC-11 and about 2% for the non-producer clone or HeLa cells. Up to 20% of the total polysomal and ribosomal RNA were precipitated from the IgG producing clone. This value correlated with the IgG synthesis of these cells which is also about 20% of the total protein produced. The results suggest that myeloma cells produce a relatively large quantity of IgG due to the presence of a large amount of specific m-RNA molecules.


Synthesis of antibody and immunoglobulins without detectable antibody function in cells responding to horseradish peroxidase.

The kinetics of immunoglobulin-synthesizing cells (IFC) and antibody-forming cells (AFC) are compared in the popliteal nodes of mice challenged, in the hind footpads, with horseradish peroxidase (PO) in Freund's complete adjuvant. A rise in the number of IFC without antibody function precedes the appearance of AFC. IFC reach peak numbers 7 days before AFC. Control experiments show that the majority of IFC without antibody function are responding to PO and not to adjuvant. Kinetic and radioautographic data suggest that IFC arise by division and differentiation; however, the doubling time of AFC is too rapid to be accounted for by cell division alone. Double staining techniques revealed the presence of immunoglobulin and antibody in different compartments of the same cell in 5 to 15% of the AFC. It is postulated that some AFC are recruited, possibly from cells already synthesizing immunoglobulin determinants.


Affinity chromatography of human leukocyte and diploid cell interferons on sepharose-bound antibodies.

Interferons produced in human peripheral leukocytes (LE) and foreskin fibroblast (FS-4) cells were subjected to affinity chromatography on Sepharose-bound globulins from rabbits immunized with these interferons. Anti-LE interferon sera neutralized both interferons, but titers against FS-4 interferon were consistently lower than those against LE interferon. Anti-FS-4 interferon sera neutralized only FS-4 but not LE interferon. Accordingly, affinity columns constructed with anti-FS-4 globulin excluded LE but not FS-4 interferon, whereas those prepared with anti-LE interferon globulin bound and eluted both LE and FS-4 interferons. Purification of native interferons of both types on anti-LE interferon-Sepharose ranged from 680- to 3,600-fold and recoveries from 72 to 126%. Specific activities of eluate pools varied from 4 to 30 times 10-6 reference (B, 69/19) units per milligram protien.


Estimation of fibrinogen-fibrin related antigen by continuous flow analysis.

A precise method for the determination of fibrinogen-fibrin related antigen (FR antigen) in an automated tanned red cell haemagglutination inhibition system is described. In a continuous flow system aliquots of serum are mixed with a dilution of rabbit anti-human fibrinogen serum. The FR antigen neutralizes the anti-fibrinogen serum and on addition of tanned human red cells sensitized with human fibrinogen, the cells agglutinate according to the remaining anti-fibrinogen activity. The agglutinates are removed and the remaining free cells are haemolysed with saponin and the colour measured at 550 nm. The density of the colour formed is in proportion to the amount of FR antigen present. The range in 102 normal males was 4.8 plus or minus 2.4 mug/ml. A significant increase in the levels of FR antigen throughout pregnancy was found, the highest levels being in the latter half of the third trimester. The levels of FR antigen in 31 normal urines was 0.46 plus or minus 0.44 mug/ml.


CLq precipitin in the sera of patients with allergic vasculitis (Gougerot-Ruiter Syndrome).

The sera from two well-documented cases of allergic vasculitis were examined for the presence of C1q precipitins. Both sera contained material capable of precipitating C1q in agarose gel. The material from one of the sera was partially purified using ammonium sulfate precipitation. Sephadex G-200 filtration, and DEAE-cellulose chromatography. Attempts to identify the nature of C1q precipitin were unsuccessful, but it resembled the high-molecular-weight precipitins of sera from patients with systemic lupus erythematosus. In a lesion, deposition of fibrinogen, immunoglobulins, and complement were noted mainly in the vessel walls. No correlation between immunoglobulin and complement deposition in the skin and the presence of C1q precipitins in the blood could be established.


Isolation and characterization of epidermal ribosomes.

The conditions required for isolation of ribosomal particles from guinea-pig epidermis and half-root cells have been studied. Density-gradient patterns of the ribosomes following isolation from either tissue under a wide variety of conditions are essentially the same. Monomeric ribosomes are the predominant species isolable although polymeric ribosomes and subunits can be identified. The density-gradient pattern is not related to runoff during preparation. Detergent extraction is required for maximal recovery of particles from epidermis or wax-epilated hair roots even without detergent. The yield of ribosomes from both epidermis and hair roots is greatest in buffers with potassium concentrations between 100 and 250mM. Yield is decreased in buffers with magnesium concentrations above 5mM. Activity in an in vitro amino acid-incorporating system is unaffected by potassium concentration and is highest at magnesium concentration of 3mM. Activity of epidermal ribosomes is inhibited by the wax-epilation method while hair root-cell ribosomes are equally active following preparation with either latex or wax. The isolated ribosomal particles are unstable at 4 degrees C.


Cross-linking of fibrinogen and fibrin by fibrin-stablizing factor (factor XIIIa).

Factor XIIIa catalyzed intermolecular cross-linking of fibrinogen at initial rates that varied in direct (first order) proportion to the fibrinogen concentration, which differed from the well known zero order relationship in fibrin cross-linking. Preferential cross-linking of gamma-chains occurred with both substrates. The differences in rates and order of reaction were attributed mainly to effect of self-alignment of the gamma-chains in fibrin which enabled the cross-linking enzyme to interact with paired chains as a single rather than two independent entities. Studies on mixtures of fibrinogen and fibrin indicated factor XIIIa had near equal affinities for the two substrates. At low concentrations with which cross-linking of fibrinogen proceeded sluggishly compared to fibrin, fibrinogen inhibited stabilization of fibrin clots by competitively partitioning factor XIIIa away from the fribin. Additional inhibition arose from cross-linking of fibrin in soluble combination with fibrinogen in mixtures containing fibrinogen in large excess over fibrin. The observations demonstrate ways in which fibrinogen normally helps to suppress both polymerization and cross-linking of small amounts of fibrin produced within the circulation. At very high concentrations above 30 mg. per milliliter, fibrinogen underwent cross-linking at faster initial rates than the cross-linking of fibrin. Rapid cross-linking of concentrated fibrogen raises the possibility that filtration enrichment may be a factor contributing to abnormal formation of the highly insoluble fibrinogen deposits occurring in atheromatous tissue.


Secretory activity and aryl acid content of serum, urine, and cerebrospinal fluid in normal and uremic man.

Serum from uremic human subjects causes net fluid secretion in proximal straight tubules isolated from rabbit kidneys in a manner similar to paraaminohippuric acid. In the present study, we determined the relation between the concentration of aryl acids (hippuric acid, benzoic acid, etc.) In serum, urine, and cerebrospinal fluid (CSF) and the capacity of the biologic fluids to cause fluid secretion in renal tubules. The concentration of aryl acids in serum and urine as estimated by fluorometric assay (Fl-Hipp) was related to the secretory activity (SA) estimated by bioassay in a direct linear fashion over a 10,000-fold range of concentrations. Fl-Hipp and SA were strikingly elevated in the serum of uremic patients. Hippuric acid determined by gas-liquid chromatography accounted for approximately one-fourth of the secretory activity of serum and urine; benzoic acid was present only in trace amounts; the remainder of the secretory activity of uremic serum is probably due to derivatives of aryl acids which are detected as Fl-Hipp. The relation between creatinine clearance and the SA or Fl-Hipp concentration of serum was hyperbolic; both the SA and Fl-Hipp content of serum increased sharply when creatinine clearance fell below 10 ml. per minute. The SA and Fl-Hipp content of CSF was increased in uremic patients; however, the serum content exceeded that of the CSF by more than fourfold suggesting an exclusion mechanism for aryl acids in the central nervous system. We conclude that the secretory activity of uremic serum is due to the accumulation of aryl acids, probably of the hippurate class, and, further, that relatively high levels of these biologically active substances may contribute to general organ dysfunction in uremia owing to their potential to act as competitive inhibitors of organic anion transport.


Tympano-nasopharyngeal shunt operation. A new method of middle ear ventilation.

The tympano-nasopharyngeal shunt operation is recommended as a "substitute" Eustachian tube. An experimental study regarding the efficacy of tympano-nasopharyngeal shunt operation was conducted in two dogs. Finally, four patients with complete tubal stenosis were operated on by this new method within a period of one year, with no postoperative complications. The hearing improved and patients were able to inflate their middle ears. The method is claimed to have the following advantages: permanent ventilation of the middle ear with preservation of an intact drum; the middle-ear pressure can be increased by Valsalva or Politzer manoeuvres; moderate technical difficulties; no risk of postoperative complications; and suitable in children as well as adults. The disadvantages seem to be: drainage not ensured; minor risk of ascending infection.


Vocalizations of White Carneaux pigeons during experiments on schedule-induced aggression.

Two types of vocalizations of White Carneaux pigeons were identified in experiments on schedule-induced aggression and were given pictorial representation in sound spectrograms. Characteristics of these vocalizations are examined in the context of previous descriptions of vocalizations of several varieties of pigeons during aggressive and sexual encounters in naturalistic settings. These earlier descriptions portrayed vocalizations with mnemonic phrases and the symbolds of dictionary pronunciationmdata are presented that indicate that the analysis of social encounters between pigeons during schedule-induced aggression may be aided by employing these and other vocalizations as dependent variables.


The multiplication of Nodamura virus in insect and mammalian cell cultures.

Nodamura virus multiplied in mosquito cell lines, as determined by infectivivity assays in adult honey bees (Apis mellifera) and wax moth larvae (Galleria mellonella). Titres of more than 10-7 and 10-5 bee LD50 /ml were obtained in culture fluids of Aedes albopictus and Aedes aegypti cells respectively after 10 days. Comparable titres were obtained after several months, during which the cultures were subdivided up to six times. Nodamura virus also multiplied in BHK cells and yielded titres of 10-4-8 to 10-6-6 mouse LD50/ml and 10-5-1 to 10-7-1 wax moth LD50/ml in culture fluid 1 to 4 days after infection. No c.p.e. was observed in infected cells.


Isolation of ribosome-like sturctures from Pichinde virus.

Three classes of mamalian ribosome-like structures were found to be associated with purified Pichinde virus preparations. These structures, possessing sedimentation coefficients of 80S, 60S and 40S, were sensitive to EDTA dissociation and possessed a buoyant density in caesium chloride of 1-61 g/ml, a value analogous to that displayed by BHK21 cell ribosomes. Analyses of RNA components associated with ribosomal particles of Pichinde virus established that 28S and 18S RNAs could be extracted from 80S monosomes. Similarly, 28S and 18S RNAs were derived, respectively, from 60S and 30S ribosomal subunits. Virus-specific 31S and 22S RNAs, as well as 28S and 18S RNAs, could be isolated from the heavy region of sucrose gradients. An additional 15S type of RNA, which was subsequently shown to be a component of intact virus particles, was also isolated from the heavy region.


Frog virus 3 replication: electron microscope observations on the sequence of infection in chick embryo fibroblasts.

The replication of frog virus 3 in primary chick embryo fibroblasts has been studied by examination of thin sections with the electron microscope and the assay of infectious viurs. Uptake of frog virus 3 by the cells was observed to occur by pinocytosis and this may be the method of entry. Early in infection (i h p.i.) marked margination of the nuclear chromatin occurred and the chromatin remained in this condition throughtout the infection. Foci of infection were first detected in the cytoplasm of cells 24 h p.i. when production of infectious virus commenced. These foci appeared as electron translucent areas containing fine grains, surrounded by degenerate mitochondria. The foci usually contained virus particles. At this time budding of virus particles at the plasma membrane occurred. Later in infection at 36 and 48 h p.i. large numbers of virus particles were detected in the cytoplasm of cells either scattered loosely throughtout the cell, arranged as clusters or in paracrystalline arrays. Extensive budding at the plasma membrane then took place. Virus particles were detected in the nucleus of the cells at these late stages and it is possible that the virus may infect and replicate at this site. Throughout the productive stages of infection aberrant forms of the virus, namely particles devoid of cores, incompletely assembled particles and elongated bacilliform particles were noticed.


Electrophoretic analysis of capsid and non-capsid polypeptides of echovirus 12, and selective inhibtion of the formation of virus particles by actinomycin D.

Electrophoretic analysis of purified echovirus virus particles yielded four polypeptides of mol. wt.  37000, 30000, 25000 and 7600. The 75S empty capsids of echovirus 12 lack the 25000 and 7600 mol. wt. polypeptides, and possess polypeptides of 41000 mol. wt. A total of 14 virus-induced polypeptide species was found in the cytoplasm of infected cells. Actinomycin D reduced the synthesis of virus, virus RNA, and virus polypeptides and also reduced the proportion of virus particles to empty capsids in the virus yields.


A linguistic and cognitive persepctive on retardation.

The idea of critical readiness periods for both language learning and cognitive development was reviewed and related to mental subnormalities. A basic model of a synthesized theory of language and cognition was presented, and a theoretical "Basal Person" was constructed to illustrate a new perspective on retardation. The general conclusions reached were that (a) the basal person represents the lowest normal level of cognitive linguistic development, and (b) retardation can be defined in terms of impeded or disrupted development during critical readiness periods.


Supersensitivity to dopamine agonists following unilateral, 6-hydroxydopamine-induced striatal lesions in mice.

Following an injection of 6-hydroxydopamine into the left striatum, mice initially circled spontaneously in the direction of the lesion and gradually developed an ability to circle in the opposite direction when challenged with apomorphine or L-dopa. Dose-response curves for apomorphine- and L-dopa-induced circling rates shifted to the left as the duration between the time of the 6-hydroxydopamine injection and the time of testing increased from 2 to 30 days. There was a positive correlation between the rate of apomorphine-induced circling and the reduction in the dopamine concentration in the lesioned forebrain. Doses of apomorphine and L-dopa required to elicit circling responses were 1/6 to 1/10 of those required to increase locomotor activity in normal mice. These data support the concept of development of supersensitivity of postsynaptic dopaminergic receptors in the lesioned striatum.


Blockade by narcotic drugs of naloxone-precipitated jumping in morphine-dependent mice.

A dose regimen for administration of morphine, test drugs with potential to cause physical dependence and naloxone was determined to allow within one experimental day acquisition of morphine-dependent mice and evaluation of the narcotic drugs for their ability to prevent naloxone-precipitated jumping. This test procedure can be used to assess capacity of unknown drugs to suppress morphine withdrawal symptoms; the mechanism of suppression can be subsequently determined in secondary tests. However, for known morphine-like analgesics, the test procedure appears to reliably assess physical dependence properties. The results obtained on subcutaneous administration of five selected narcotic drugs and apomorphine show that their order of potency was methadone greater than meperidine equal apomorphine greater than d-propoxyphene greater than pentazocine. Codeine, also tested subcutaneously, did not substitute at sublethal doses. Except for apomorphine, which might have masked naloxone-precipitated jumping by inducing behavioral aggression, the order of potency compares favorably with the degree of physical dependence reported in humans. Thus, the described procedure might be employed to evaluate morphine substitution and hence potential physical dependence liability of unknown narcotic-like analgesics.


Quantification of the analgesic activity of narcotic antagonists by a modified hot-plate procedure.

The analgesic activity of morphine and the narcotic antagonists, pentazocine, cyclazocine, levallorphan and nalorphine, was assessed in the rat using two hot plates: one maintained at 49.5 degrees C and the other at the "standard" 54.5 degrees C. The analgesic effects of morphine using the 49.5 degrees C hot plate were of a significantly greater magnitude than its effects using the 54.5 degrees C hot plate for both nontolerant and morphine-tolerant subjects. Dose-related effects were observed with all of the narcotic antagonists tested using the 49.5 degrees C hot plate; only the highest dose of pentazocine exhibited activity using the 54.5 degrees C hot plate. Naloxone (3.0 mg/kg) antagonized the analgesic effects of morphine and all of the narcotic antagonists, but was without activity itself when tested using the 49.5 degrees C hot plate at doses as high as 30 mg/kg. Aspirin was also inactive using the 49.5 degrees C plate, whereas physostigmine increased latencies only at a dose that produced severe motor deficit. A low temperature hot plate is recommended for evaluating the analgesic activity of narcotic antagonists in the rat. This simple procedure provides results which are dose-related, quantifiable, reproducible, of a large magnitude and specific.


The effects of age on the development of tolerance to and physical dependence on morphine in rats.

Changes in growth rate and the development of tolerance and physical dependence during repeated morphine administration were compared in different age groups of rats. Chronic treatment of rats for 3 weeks with increasing doses of morphine resulted in an inhibition of the growth rate of older rats but not of younger rats. The magnitude and time course of the loss of body weight upon morphine withdrawal in morphine-treated rats were independent of the age of the animal. Morphine increased the "pain" threshold in rats as monitored by the electric foot-shock technique. These analgesic effects were greater in 12-week-old rats than in 4- or 7-week-old rats. Repeated administration of morphine resulted in a gradual loss of the analgesic response to morphine in all age groups. However, the rate of development of tolerance to morphine was faster in younger rats than in older rats when these animals were injected repeatedly either with a fixed dose or with equipotent doses of morphine. These investigations indicate that the rate of the development of tolerance to morphine is significantly affected by the age of the subject.


Effects of chronic morphine administration on the reproductive system of the male rat.

The effects of chronic morphine administration on a variety of rat organs were examined. Only the prostates and seminal vesicles were affected by a 3-day period of morphine pellet implantation. In these organs, particularly the seminal vesicles, morphine produced a marked decrease in both the wet and dry tissue weight and a reduction in their secretory activity. This apparent morphine-induced atrophy of these important accessory sex organs was not due to a change in the nutritional status of the animals but rather appeared to be associated with a pronounced (87 percent) reduction in the serum testosterone levels of morphine-treated rats when compared to control levels. The effect of morphine on the secondary sex organs was reversed by withdrawing the animals from morphine administration for a period of 7 days. These data suggest that the role of physiological and endocrinological factors in the narcotic addict's sexual difficulties be examined.


The effects of methadone on maternal-fetal interactions in the rat.

Female Sprague-Dawley rats received methadone (25 mg/kg/day) by gavage throughout gestation. Water-gavaged rats served as controls. Fetuses were delivered by cesarean section when parturition was imminent. Our results indicate that methadone may interfere with fetal development and maternal-fetal interactions to some degree. The observed alterations were as follows: fetal growth retardation, an interference with the triggering of parturition once normal delivery size is attained and possible positional malformations.


Developmental changes of membrane electrical properties in a rat skeletal muscle cell line.

1. The developmental changes of the cell membrane electrical properties were studied with micro-electrodes in a rat skeletal muscle cell line. 2. The resting potentials in myoblasts were minus 71 plus or minus 3 mV (mean plus or minus S.D.) and those in myotubes which were formed by fusion of myoblasts were minus 69 plus or minus 3 mV. There was no developmental change in the resting potential during the period examined. 3. The ionic mechanism for the resting potential was the same in myoblasts and myotubes. The resting membrane was almost exclusively permeable to K ions, while permeability to Na ions was not detectable. There was a small permeability to Cl ions. 4. The specific membrane resistance and capacitance were 8 k omega. cm-2 and 1 muF/cm-2 for myoblasts and 12 k omege. cm-2 and 5 muF/cm-2 for myotubes, respectively. 5. Action potentials in myoblasts were evoked by anode break stimulation. They were small and did not overshoot zero membrane potential. The action potentials in myotubes were larger, and had an average overshoot of 32 plus or minus 7 mV and a maximum rate of rise of 93 plus or minus 28 V/sec. 6. The current-voltage relation was examined. Delayed rectification was found in myotubes but not in myoblasts.


Sodium and calcium components of the action potential in a developing skeletal muscle cell line.

1. Developmental changes in action potential properties were studied in a clonal rat skeletal muscle cell line. 2. Small action potentials were evoked in mononucleate myoblasts. No spike was seen in Na-free saline. A similar spike was evoked in a medium where all NaCl was replaced by LiCl. No spike was evoked when NaCl was replaced by CsCl. 3. Action potentials overshot zero membrane potential in multinucleate myotubes. The action potential was composed of two components, an initial fast spike and a hump on the falling phase or in some cases a distinct second peak. 4. Teh overshoot of the initial fast spike decreased when the external Na concentration was decreased. 5. In saline with 10 mM-Ca the second component often formed a distinct peak following the initial fast spike. A slow regenerative potential was evoked in Na-free media with a depolarizing current pulse. 6. In saline containing BaCl-2 instead of CaCl-2 there was always a second peak, the overshoot of which changed with external Ba concentration. A slow regenerative potential was evoked in Na-free, Ba-saline. The membrane conductance at the peak of the Ba-action potential was larger than in the resting state. 7. In adult rat skeletal muscle, the shape of the action potential was not changed when Ca was replaced by Ba. No action potential was evoked in Na-free Ba-saline or Ba-saline with tetrodotoxin (3 times 10-7 M). 8. The significance of the Ca component in the developing muscle is discussed.


Neuroleptic agents of the benzocycloheptapyridoisoquinoline series. 1. Syntheses and stereochemical and structural requirements for activity of butaclamol and related compounds.

The syntheses and the structural and stereochemical requirements for antagonism of (+)-amphetamine-induced sterotypy are described for a series of benzocycloheptapyridoisoquinoline derivatives. One of these compounds, (plus or minus)-(4a,13b-trans)[3(OH),13b(H)-trans[-3-tert-butyl-2,3,4,4a,8,9,13b,14-octahydro-1H-benzo[6,7]cyclohepta[1,2,3-de]pyrido[2,1-a]isoquinolin-3ol hydrochloride (butaclamol hydrochloride, USAN), is currently being studied in man. The relationship between structure and antiamphetamine activity in this class of compounds is discussed.


Synthesis and pharmacology of some 2-aminotetralins. Dopamine receptor agonists.

A series of 2-amino-1,2,3,4-tetrahydronaphthalene compounds bearing substituents on the nitrogen and in the aromatic ring was synthesized from beta-tetralone intermediates. Compounds were screened in vivo for dopaminergic activity using tests in which apomorphine was especially active. It was found that apparent dopaminergic activity is inherent in 2-dialkylaminotetralins, the dipropylamine substitution being the most consistently productive amine group studies. Activity was greatly enhanced by proper substitution in the aromatic ring. The 5,6-dihydroxy group was the best potentiating group found. These data support the idea that the extended conformation for the phenylethylamine moiety of ampmorphine and dopamine is favorable for dopaminergic agonist activity. They also suggest that an unetherified catechol group may not be essential for such activity.


Dependence of photosensitivity of bileaflet lipid membranes upon the chlorophyll and carotenoid content.

Bileaflet lipid membranes were formed from solutions containing lecithin, chlorophyll and carotene in various concentrations. If all the above components were present at sufficient concentrations the membranes were photosensitive; i.e., a photocurrent was produced if a redox potential gradient was present across the membranes. The presence of chlorophyll and carotene were essential for the photosensitivity of the membranes. Photoresponse could be elicited by illuminating the membrane with light which did not excite carotene. On the other hand, elimination of the part of the light spectrum which excites chlorophyll led to the abolition of the photoresponse. The findings of this study are consistent with the assumption that the excited chlorophyll chromophores allow electron exchange at the membrane-water interface while the presence of carotene allows electron movement across the "bulk" lipid membrane.


13C nuclear magnetic resonance studies of egg phosphatidylcholine.

Spin lattice relaxation times (T1) and apparent spin-spin relaxation times (T2) derived from linewidth have been used to investigate model membranes composed of egg yolk phosphatidylcholine. T1 measurements appear to be largely dominated by segmental motion and as a consequence are not very sensitive to small changes in membrane structure. On the contrary, apparent T2 times are shown to be sensitive to such changes in the membrane and are thus suggested as a useful tool for further investigation of membrane structure.


Characteristics of a cytotoxic human lymphocyte-dependent antibody.

Lymphocyte-dependent antobody (LDA) from the blood of a patient with choriocarcinoma was characterized in an allogeneic in vitro system. The antibody reacted with specific traget cells, including cells from the patient's husband. Antibody-coated traget cells were damaged by normal lymphocytes from man and other species. Neither cytotoxic, complement-dependent antibody nor sensitized cytotoxic lymphocytes were found in the patient. LDA activity was associated with IgG gamma-globulin by G-200 Sephadex filtration, electrophoretic mobility, and reactivity with anti-IgG, but there was no activity associated with IgM immunoglobulin. Sera from 14 of 16 normal donors lacked detectable LDA activity, and only low levels were found in sera from the other two donors.


Lack of correlation between malignancy and sensitivity to killing by concanavalin A.

Eight mouse cell lines and seven hybrid clones, both malignant and nonmalignant, were tested for possible correlations between malignancy and sensitivity to killing by concanavalin A (Con A). These cells included six highly malignant and two less malignant cell lines, two malignant and three nonmalignant hybrid clones derived from five different crosses, and two malignant hybrid clones segregated from a cross between malignant and nonmalignant cells. The malignancy of the cells was determined by their ability to grow progressively in irradiated, syngeneic newborn mice and to kill the host. All these cells, except one, showed similar sensitivities to killing by Con A. No correlation could be established between the malignancy of a cell line or of a hybrid clone and its sensitivity to the lectin.


Endotoxin-stimulated immune response to modified lymphoma cells.

Bacterial endotoxin was administered with iodoacetamide-modified P1798 lymphoma cells to immunize syngenic BALB/cJ mice against this lymphoma to which they are naturally unresponsive. Three or four vaccinations with endotoxin (6.6 mug/injection) alone or the modified cells alone did not produce host resistance. A significant number (30 percent) of mice receiving both endotoxin and modified cells rejected a subsequent implant of viable tumor cells. Even those mice having progressive tumor growth exhibited prolonged survival. High doses of endotoxin given with the modified P1798 cells caused 70-75 percent of the mice to reject the tumor implants. When resistance developed, antibodies reacting with tumor cell membrane were demonstrable. These results indicate that B-lymphocyte stimulators can produce an effective immune response against lymphoma cells.


Desmosterol in rat central and peripheral nervous systems during normal and neoplastic growth.

Desmosterol (5, 24-cholestadien-3beta-ol; delta 24-cholesterol; 24-dehydrocholesterol), an immediate precursor of brain cholesterol, increased in malignant intracranial tumors induced in rats by nitrosourea derivatives. The average increase in desmosterol was higher in intracerebral gliomas than in neurinomas of the trigeminal nerve. Similarly, desmosterol increased only slightly in developing normal trigeminal nerve compared to the high levels observed in developing cerebrum. The differences may have been partly related to the predominantly growing cell type, i.e., glial (central nervous system) or Schwann (peripheral nervous system) cells seen at the time of study.


Renal function after release of chronic unilateral hydronephrosis in man.

Differential renal function studies performed on ten patients after release of unilateral hydronephrosis revealed that the previously obstructed kidney exhibits abnormalities in a number of physiological indexes. Many of the obstructed kidneys had an impairment of glomerular filtration rate, concentrating ability, acidification, sodium reabsorption and tubular maximal secretion of para-aminohippurate with normal urinary dilution. Despite impairment of sodium and water reabsorption, none of these patients, nor 20 additional patients, had a significant postobstructive diuresis from the previously obstructed kidney. All of the patients had normal total renal function. Thus, the changes observed were a result of the obstructive injury and were not related to azotemia or aberrations in water or sodium metabolism.


[Genetic problems in pediatric cardiology (author's transl)].

The genetic background of cardiovascular malformations is discussed. Congenital heart disease may occur as a consequence of chromosomal anomalies and of single Mendelian gene defects, respectively. However, in the vast majority of cases, the hypothesis of multifactorial inheritance is the most plausible one. The rules of genetic counselling, which plays an increasingly important role in pediatric cardiology, are briefly outlined. In those cases which fit the multifactorial inheritance hypothesis, counselling depends on empiric recurrence risks.


[Severe metabolic diseases in neonates. Diagnosis and treatment (author's transl)].

Life-threatening diseases in the newborn period might be due to rare inborn errors of metabolism. Clincal symptoms, diagnostic approach and therapy are outlined in some inherited diseases of amino acid-, carbohydrate and organic acid metabolism. A proposual for initial management in a suspected case is made.


[Recurrent urinary tract infection in childhood. Diagnosis, treatment, prognosis (author's transl)].

Infection of the urinary tract in childhood is common. It may start already in neonates or infants. Clinical signs are not always present but asymptomatic socalled bacteriuria may occur at any age. The earlier a child contracts the infection the more common are uncharacteristic clinical signs like loss of appetite, a raised temperature, parenchymatous icterus and, finally signs of involvement of the central nervous system. During the last few years purposeful research has established the important fact that, if there has been a urinary tract infection particularly in the first months of life, recurrence may more often be asymptomatic than on the first occasion. A mid-stream specimen is diagnostically valuable. If this does contain any bacteria, then supapubic aspiration from the bladder is useful in enabling us to start a specific, if possible bactericidal, therapy. Asymptomatic bacteriuria may at any time lead to clinical signs of pyelonephritis, particularly during periods of stress. Such silent unrecognized cases of asymptomatic bacteriuria may, we feel, lead to pyelonephritic nephrosis in a so far unknown percentage of cases.


[Positive end-exspiratory pressure for the treatment of respiratory distress syndrome with indirect increase of pressure. Clinical experience with the Pulmarca box (author's transl)].

Harrison could demonstrate the benefit of exspiratory grunting in respiratory distress syndrome. Probably it delays alveolar collapse and promotes gasexchange. Since the publication of Gregory different methods for therapeutic use were practised. Our report deals with own investigations with continous negative chest wall pressure (CNP). Effect, indication and complications are discussed especially.


[Disturbances of cardiac rhythm in neonates and infants (author's transl)].

The authors report on the kinds and frequency of cardiac rhythm disturbances observed in neonates and young infants at the University Children's Hospital of Innsbruck within the past 3 years. Four children who were already in utero suspected to have arrhythmia are dealt with in greater detail. The etiology and pathogenesis of rhythm disturbances are briefly outlined and the therapeutic measures summarized.


[The plasma-protein-binding of Clindamycin Cephazolin and Cephradin in neonates and adults (author's transl)].

In pooled serum of 12 healthy adults and 12 neonates (blood taken from the umbilical cord) the free and protein-bound parts of Cephazolin, Cephradin and Clindamycin were tested by equilibrium dialysis in relation to the concentration of the antibiotic. In the serum of adults at a concentration of  36 mcg/ml the free part of Cephazolin amounted to 16%, at a concentration of 35 mcg/ml the free Cephradin was 87%, at a concentration of 97 mcg/ml the free Clindamycin was 16%. The binding constant k of Cephazolin was 12.0 (rise-constant 0.58), of Cephradin 0.26 and of Clindamycin 15.8 (rise-constant 0.58). When concentration of antibiotics rose, the free part of Clindamycin and Cephazolin increased more than with Cephradin. At a concentration of 30--42 mcg/ml the differences between the sera of adults and neonates were 26.4% with Cephazolin, 3.7% with Cephradin and 3.1% with Clindamycin (concentration 92--97 mcg/ml). In neonates the free part of Cephazolin was 43%, of Clindamycin 19% and of Cephradin 90%. The lower ablumin content in serum of neonates (3.7 g%) does not altogether explain the reduced protein-binding. In neonates a different affinity for binding has to be assumed.


[Congenital defect of the scalp in 4 generations (author's transl)].

In the parietal region of a newborn male child, two skin lesions are found. An according sceletal defect could not be proved. These skin lesions are well known in the family of the mother. In the last three generations one member of the family showed those defects. A survey of literature gives more than 20 reports concerning these lesions in families, reporting cases where brothers and sisters are concerned up to three generations, and several cases where the underlying bone is concerned too.


[The differential diagnosis of the Meckel syndrome and the Ellis-van-Creveld syndrome with encephalocele (author's transl)].

The differential diagnosis of Meckel's syndrome and Ellis-van-Creveld's syndrome with encephalocele is summarized utilizing two own observations. Radiographic criteria are of special importance. In EvCS typical signs of chondrodysplasia are present whereas in MS we found pelvic changes similar to Down's syndrome and striking rhomboid deformities of the tibiae. Clinically relevant is ectodermal dyplasia in EvCS, especially, when cystic kidneys in MS are not palpable.