Ocular penetration of chloramphenicol. Effects of route of administration. Chloramphenicol was applied topically to the eye in ointment, as a powder, or injected subconjunctivally and intravenously in rabbits. Aqueous humor samples were taken at varying time intervals up to six hours and analyzed for chloramphenicol using gas-liquid chromatography. The topical route using ointment and the subconjunctival injection route produced bacteriostatic concentrations of chloramphenicol in the aqueous humor lasting for several hours, while the topical powder and intravenous routes yielded relatively low concentrations. As compared with the other means of drug delivery, ointment was the most efficient in that it provided the highest aqueous concentration per total amount of drug administered.


Is obesity an endocrine condition?

Is obesity an endocrine condition? Obesity is an extremely common condition, affecting one-third of the adult population of Australia. In the great majority of cases, the problem is due to calorie imbalance resulting from an excessive food intake coupled with inadequate exercise. Endocrine causes of obesity are relatively uncommon, but should be excluded in every case. This article compares the clinical features of primary obesity and endocrine obesity, and outlines the investigations which may be used to exclude endocrine causes for obesity.


[Use of normalized velocities in the echocardiographic evaluation of left ventricular performance]. The mean circumferential contraction rate of the myocardial fiber cell (Mvcf) and the ejection fraction (EF) are echocardiographic parameters commonly employed in the assessment of left ventricular performance. In cases where septal asynchonism due to fibrosis or bundle-branch block make their determination impossible, however, one is forced to use parameters obtained from movement of the posterior wall. Investigation of normal subjects and patients with idiopathic hypertrophic subaortic stenosis showed that the "normalized" systolic velocity of the posterior wall (Vpws) and the non-normalized mean velocity (PWV) closely fitted Mvcf and that Vpws offered a good fit with EF. It is suggested that a non-invasive way of obtaining sufficiently reliable data for the evaluation of cardiac performance is offered by these two parameters.


The prevalence of tapeworms in dogs during the Hydatid Limitation program in Tasmania. The hydatid Limitation Program in Tasmania began in 1965 with the annual purging of dogs to identify areas of high prevalence of Echinococcus granulosus combined with a strong educational program aimed at preventing access to offal by dogs. From 1969 to 1975 aenia spp detected in dog purges were submitted for identification and changes in annual prevalences analysed for each species. Despite a significant reduction in the prevalence of E. granulosus since the beginning of the program, the control measures involved have apparently not predisposed to any significant change in the prevalence of T. ovis and T. hydatigena during the period of this survey.


Comparison of clinical features in HLA-B27 positive and negative patients with ankylosing spondylitis. The clinical features of ankylosing spondylitis (AS) were compared in 63 HLA-B 27 positive (+) and 15 B27 negative (-) individuals with this disease. There were no differences in age at onset, functional class, degree of deformity, pain, severity of X-ray changes, or frequency of peripheral joint involvement or of reconstructive orthopedic surgery. These data demonstrated that skeletal manifestations of AS were essentially the same in B27(+) and (-) patients, and provide no evidence for the speculation that AS in B27(-) patients is milder or is a different disease from that occurring in B27(+) patients. On the other hand, acute anterior uveitis was found to be significantly more common in B27(+) patients, a fact suggesting that the "uveitis of AS" may in fact be an independent condition occurring in B27(+) individuals, rather than a manifestation of AS per se.


[Biological properties of 1,2-benzisothiazole compounds. Spasmolytic effect of N-(cyclohexylaminoethyl)-1,2-benzisothiazole-3-carboxyamides benzene-substituted on segments of human myometrium in virto]. A report is given on the spasmolytic effect of two benzisothiazolcarboxyamides (compound A and compound B). These drugs were able to inhibit the stimulant action of histamine on human isolated myometrium. The potency of the two compounds exceeded by ten times that of ritodrine (a beta adrenergic stimulant), the efficacy was slightly higher (20-30%) than that of papaverine. This pharmacological effect is discussed on the light of the spectrum of activites of the benzisothiazolcarboxyamidic compounds.


Experimental atherosclerosis in rabbits fed cholesterol-free diets. Part 7. Interaction of animal or vegetable protein with fiber. Rabbits were maintained for 10 months on a semipurified, cholesterol-free atherogenic regimen. All diets contained sucrose (40%) and hydrogenated coconut oil (14%). The protein (25%) was either casein or soya protein and the fiber (15%) was either wheat straw, alfalfa, or cellulose. Within either protein group the order for induction of cholesteremia was cellulose=wheat straw greater than alfalfa. For atherogenesis, the effect was cellulose greater than wheat straw greater than alfalfa Soya-wheat straw or soya-cellulose diets were less cholesteremic and atherogenic than their casein counterparts. When alfalfa was the fiber, the two types of protein were almost equivalent. Our results show that casein may be more cholesteremic and atherogenic than soya protein under certain conditions (cellulose or wheat straw as fiber) but the addition of alfalfa to the diet renders the two proteins equivalent.


Acute dietary effects on diurnal plasma lipids in normal subjects. The effects of different dietary carbohydrates and different dietary fats as well as of differently spaced dietary constituents on 24-h plasma free fatty acids and triglycerides were determined in healthy young males. If, in an isocaloric diet containing 15-20% protein, 37% fat and 43--48% carbohydrates, sucrose is compared with glucose, 24-h plasma triglycerides are significantly higher with the former carbohydrate. When palm oil (mainly 16 : 0 fatty acids) is compared with olive oil (mainly 18 : 1 fatty acids), 24-h triglycerides are significantly higher with the latter. If the carbohydrate component of a mixed meal is removed, alimentary lipemia is considerably greater. Our findings supplement long term studies regarding the effect of different dietary fats and carbohydrates on plasma lipids and allow calculation of "upper normal limits" for 24-h plasma triglycerides and free fatty acid patterns on isocaloric diets of "prudent" composition.


Type and amount of dietary fat affect relative concentration of cholesterol in blood and other tissues of rats. The effects of diet on tissue cholesterol disposition in the rat were studied. Growing rats were fed a nonfat dry milk supplemented with two levels of soy-bean oil (SBO) and tallow (T) such that either 30% or 50% of total dietary calories came from fat. Two of four groups of rats fed the diets with 50% of calories from fat were supplemented with 20% ground whole oats. Considering all diets, rats fed SBO had higher blood and kidney cholesterol than did rats fed T; supplementation of the diet with oats increased the plasma cholesterol of the "50%" SBO rats and , conversely, decreased plasma cholesterol of the "50%" T rats. Muscle cholesterol content was not affected by variations in dietary fat and oats. In all treatments, cholesterol concentration of epididymal fat and liver were greater in the SBO-fed than in the T-fed rats.


[Indirect measurement of intracranial pressure, with special reference to its principles and experiments with animals]. A new technique for measurement of intracranial pressure was presented. By using this method a) absolute value of pressure, b) easy, simple and inexpensive long-term measurement and c) decrease in danger of infection are obtained. The apparatus consists of an external device which converts displacement of its membrane into quantitative change of beam and an internal chamber with two membranes that is implanted in a burr hole between scalp and dura mater. These devices have the same diameter and no direct connection each other. When a pressure in the external device is varied, a pressure-displacement curve of its membrane is resulted. The pressure of the external device at the point of inflexion of the curve is representative of the pressure in the internal chamber. In the animal experiment, satisfactory results were obtained.


Radioimmunoassay of vinblastine and vincristine. 1 The cytotoxic agent, vinblastine, was conjugated to albumin, using the Mannich reaction. Rabbits immunized with two conjugates, containing differing amounts of hapten, produce antibodies which bound [3H]-vinblastine. 2 Antisera from one rabbit cross-reacted with both vinblastine and vincristine and were used to develop radioimmunoassays for measuring their concentration in plasma. 3 The antisera showed no cross-reactivity with other alkaloids or cytotoxic drugs and provided assays sensitive to a concentration of 2.1 ng vinblastine or 3.8 ng vincristine/ml of plasma added direct to the assay tubes. 4 This is sufficiently sensitive to permit the measurement of plasma vinblastine levels for up to 24 h after the intravenous administration of 15 mg of the drug.


Pulmonary haemorrhage in disseminated cardiac haemangiosarcoma. A male forestry worker presented with chest pain followed by severe continuing haemoptysis and an extensive bilateral nodular pulmonary infiltrate. A needle biopsy of lung demonstrated micronodular deposits of malignant tissue. The patient died from respiratory failure. Necropsy showed a disseminated haemangiosarcoma arising in the right atrium. Haemoglobin and serum iron levels were normal. Electron microscopy of the lung biopsy showed a close relationship between tumour cells and basement membrane and suggested that haemorrhage occurred directly from the tumour nodules. The ultrastructure of alveoli adjacent to tumour deposits was normal. This case provides further indirect evidence that the clinical and histological features of idiopathic pulmonary haemosiderosis cannot be explained by the mere occurrence of alveolar haemorrhage.


The pregnant guinea-pig as a model for studying influenza virus infection in utero: infection of foetal tissues in organ culture and in vivo. Organ cultures of guinea-pig foetal tissues showed a similar pattern of susceptibility to influenza virus to that already observed for human (Rosztoczy et al., 1975) and ferret (Sweet, Toms and Smith, 1977) foetal tissues. Respiratory, alimentary and urogenital tract tissues were susceptible whereas neural and lymphopoietic tissues were insusceptible. However, of the foetal membranes (amnion, chorion, umbilical cord and placenta) only the chorion was susceptible, in contrast to the corresponding ferret tissues, all of which were susceptible. The insusceptibility of the placenta paralleled that of human placenta which is similarly haemomonochorial in structure. Following intracardial inoculation of high titre virus (ca 10(9-4) EBID50) into pregnant guinea-pigs virus was isolated from all foetal membranes (amnion, chorion, umbilical cord and placenta), but in low titre. Although sporadic isolations were made from foetal tissues (intestine, kidney, heart, liver and spleen) there was no evidence for viral replication in these tissues. These results are discussed in relation to possible infection of the human foetus in utero with influenza virus.


X-ray microanalysis as applied to fungal tissues. Analytical electron microscopy combines the techniques of high-resolution electron microscopy and high-sensitivity X-ray microanalysis of samples. Spectrometry of the elements (characteristic X-rays produced by a scanning electron microprobe) was employed to detect some elements of Mendeleev's classification in pathogenic fungi for humans. X-ray microanalysis applied in wavelength dispersive spectrometry was used to study Coccidioïdes immitis, Paracoccidioïdes brasiliensis and Trichosporum cutaneum.


Nutritive value of mixed proteins. 2. As determined by net protein utilization and protein efficiency ratio tests. 1. A fish meal, meat meal, soya-bean meal, groundnut meal and sunflower-seed meal of known amino acid composition were evaluated individually, and combined in all possible pairs, by the estimation of net protein utilization (NPU) and protein efficiency ratio (body-weight gain: crude protein intake; PER) using rats. Each pair provided a total of 100 g protein/kg diet made up so that the amounts of the constituents were (w/w) 100:0, 80:20, 60:40, 20:80, and 0:100. 2. Marked synergistic effects were noted only for mixtures of sunflower-seed meal with soya-bean, fish and meat meals. 3. Chemical score ([amount of limiting amino acid/the rat's requirement for the same amino acid] X100; CS), but not essential amino acid index; geometric mean for the ratio, amount of essential amino acid: the rat's requirement for that amino acid, for all ten essential amino acids; EAAI), successfully predicted the rankings of all mixtures except groundnut meal-meat meal and groundnut meal-soya-bean meal, by both PER and NPU tests. 4. Although there is broad agreement linking results of PER and NPU tests with results obtained by a more practical feeding trial in which the mixtures were evaluated as supplements to cereals, neither of these two standard tests is capable of predicting in every instance the advantages to be gained by mixing protein concentrates.


Studies on conformation of soluble and immobilized enzymes using differential scanning calorimetry. 2. Specific activity and thermal stability of enzymes bound weakly and strongly to Sepharose CL 4B. Ribonuclease A (EC 3.1.4.22) and alpha-chymotrypsin (EC 3.4.21.1) have been covalently coupled, by a varying number of bonds, to Sepharose CL 4B which was activated with different amounts of CNBr. Upon increasing the number (1-8) of points of attachment between the enzyme and the matrix, the specific activities of immobilized ribonuclease A relative to its soluble counterpart decreased from 60 to 15% while the amount of protein coupled increased from 5 to 37 mg per g of sucked gel. Differential scanning calorimetry was used to determine whether the immobilization caused any changes in the physicochemical properties of the enzyme. Ribonuclease A, weakly bound to the matrix, showed almost the same behavior as the soluble enzyme. By contrast strongly immobilized enzyme exhibited a higher transition temperature (by about 5 degrees C) and a broader endotherm. Similar results were found for alpha-chymotrypsin.


Conformation studies of biologically active fragments of bovine growth hormone. Conformations of bovine growth hormone active fragments were studied using far ultraviolet circular dichroism and intrinsic fluorescence emission spectroscopy. The small fragment, A-II (segment 96-133 of bovine growth hormone), undergoes a helix to random coil structural transition between pH 5 and 10 (pKa = 7.15). At pH9, the random coil state of A-II reverts back to helix conformation as ionic strength increases from 0.01 to 1. The A-II fluorophore, Tyr-110, is quenched by a neighboring carboxyl group of Glu-111, but is only slightly affected by the secondary structural transition. The large fragment, A-I (segments 1-95 and 134-191, connected via a disulfide linkage, of bovine growth hormone), is a rigidly structured molecule with a large amount of beta-sheet structure. Trp-86 of A-I was found to reside in an aromatic and hydrophobic amino acid cluster which is only destroyed by a high concentration of denaturant. Based on the primary sequence of bovine growth hormone, conformation predictions were made using the Chou-Fasman method ((1974) Biochemistry 13, 222). Bovine growth hormone helical structures are predicted to be in segments 10-34, 66-87, 111-127, and 186-191, beta-Sheet structures are predicted to be in segments 45-54, 90-94, 101-105, 136-142, 161-165, and 174-179. Tetrapeptides 37-40, 41-44, 60-63, 129-132, 146-149, and 156-159 were predicted to be beta turns. The prediction scheme confirmed several spectroscopic observations, but it did not completely explain the behavior of bovine growth hormone peptide fragments.


Interaction of DNA with poly(L-Lys-L-Ala-Gly) and poly(L-Lys-L-Ala-L-Pro). Circular dichroism and thermal denaturation studies. Complexes of DNA with polypeptides composed of Lys, Ala, and Gly in both a sequential order, poly(L-lysine-L-alanine-glycine), and a statistical distribution, poly(L-lysine36-L-alanine28-glycine), were prepared using gradient dialysis. These polypeptide-DNA complexes were studied using ultraviolet absorption (UV) and circular dichroism (CD) to probe the conformation, binding, and melting behavior of DNA in the complex. Complexes with the sequential polypeptide showed no structural change in the DNA; however, the complexes with the random polypeptide yield CD spectra similar to phi DNA [Maniatis, T., Venable, Jr., J.S., and Lerman, L.S. (1974), J. Mol. Biol. 84, 37]. A second sequential polypeptide, poly(L-Lys-L-Ala-L-Pro)n, -DNA complex was also studied. It was found to exhibit pronounced structural changes as a function of ionic strength and poly-peptide-DNA ratio, more similar to the random sequence that the ordered sequence of the Lys, Ala, Gly polymer. Thus the importance of the composition and amino acid sequence in polypeptides which bind to DNA, even in such simple systems, is demonstrated. Evidence from thermal denaturation, employing simultaneous monitoring of CD and UV changes, supports a model in which specific polypeptides cause condensation of the DNA in the complex into an asymmetric tertiary structure. The relevance of these model systems to chromatin is discussed.


Ethoxyformylation and photooxidation of histidines in transferrins. The chemical reactivity of histidines in ovotransferrin and human serum transferrin was studied utilizing two different reactions. Upon dye-sensitized photooxidation of ovotransferrin and ethoxyformylation of human serum transferrin and ovotransferrin, losses in histidine and iron-binding activity were observed. All of the histidines in both apoproteins could be ethoxyformylated by the use of 170 to 400 molar excesses of reagent resulting in complete loss in activity. The histidines of human serum transferrin showed a greater reactivity toward the reagent than did those of ovotransferrin. The binding of each iron protected two histidines from ethoxyformylation, and in both cases the proteins remained completely active. First-order losses in histidine and iron-binding activity were observed when ovotransferrin was irradiated in the presence of methylene blue. Comparison of the first-order rates indicates the loss of two histidines per binding site accounts for the inactivation of the protein. However, iron binding did not protect ovotransferrin from photoinactivation as expected. Evidence from both modification technqiues indicates: (1) Histidines are essential for iron-binding activity. (2) There are two essential histidines in each binding site. The advantages of using two modification reactions, ethoxyformylation and photooxidation, in the study of the functional role of histidines in proteins are demonstrated in this work.


Binding specificity of the juvenile hormone carrier protein from the hemolymph of the tobacco hornworm Manduca sexta Johannson (Lepidoptera: Sphingidae). A series of analogues of insect juvenile hormone (four geometric isomers of methyl epoxyfarnesenate, several para-substituted epoxygeranyl phenyl ethers, and epoxyfarnesol and its acetate and haloacetate derivatives) was prepared to investigate the binding specificity of the hemolymph juvenile hormone binding protein from the tobacco hornworm Manduct sexta. The relative binding affinities were determined by a competition assay against radiolabeled methyl (E,E)-3,11-dimethyl-7-ethyl-cis-10,11-epoxytrideca-2,6-dienoate (JH I). The ratio of dissociation constants was estimated by plotting competitor data according to a linear transformation of the dissociation equations describing competition of two ligands for a binding protein. The importance of the geometry of the sesquiterpene hydrocarbon chain is indicated by the fact that the binding affinity is decreased as Z (cis) double bonds are substituted for E (trans) double bonds in the methyl epoxyfarnesenate series; the unepoxidized analogues do not bind. A carboxylic ester function is important although its orientation can be reversed, as indicated by the good binding of epoxyfarnesyl acetate. In the monoterpene series, methyl epoxygeranoate shows no affinity for the binding protein, but substitution of a phenyl or p-carbomethoxyphenyl ether for the ester function imparts a low, but significant affinity. These data taken together with earlier results indicate that the binding site for juvenile hormone in the hemolymph binding protein is characterized by a sterically defined hydrophobic region with polar sites that recognize the epoxide and the ester functions.


Purification using polyethylenimine precipitation and low molecular weight subunit analyses of calf thymus and wheat germ DNA-dependent RNA polymerase II. DNA-dependent RNA polymerase II from calf thymus has been successfully purified using polythylenimine precipitation. Thus, 5-6 mg of nearly homogeneous homogeneous trna polymerase II (greater than 96% pure) can be prepared from 1 kg of calf thymus with three chromatography steps following extraction and precipitation of the enzyme from the polyethylenimine pellet. This procedure eliminates the high salt extraction of chromatin previously used in purification of this enzyme and makes possible the large scale preparation of mammalian RNA polymerase II. Calf thymus polymerase II prepared by this method is greater than 90% form IIb and consists of ten different subunits having the following molecular weights: 180 000; 145 000; 36 000; 25 000; 20 000; 18 500; 16 000; 15 000; 12 000; 11 500. The homologous enzyme isolated from wheat germ is greater than 90% form IIa and contains subunits of the following molecular weights: 206 000; 145 000; 44 000-47 000; 24 500; 21 000; 19 000; 17 000; 14 000; 13 500. The wheat germ and calf thymus enzymes exhibit similar subunits structures, but the molecular weights of individual subunits are clearly different between the enzymes. Wheat germ RNA polymerase II is 50% inhibited by 0.271 microng/mL of alpha-amanitin, a level 30-fold higher than that found for calf thymus RNA polymerase II. These enzymes are further distinguished by the absence of antigenic cross reactivity.


Effect of anisomycin on the cellular level of native ribosomal subunits. Treatment of Ehrlich ascites cells with anisomycin induces an almost threefold increase in the level of native 60S ribosomal subunits. This increase is not the result of an increase in rate of synthesis or transport of these subunits but is caused by a defect in the joining of the 60S subunits to the smaller initiation complex to form an 80S complex. Experimental evidence for such a blocking of the "joining reaction" could be found in the formation of "half-mer"-type oligosomes and by the release of extra 40S subunits when these oligosomes were treated with ribonuclease. Cycloheximide, an inhibitor of the translocation reaction, and inhibitors of the initiation prevent the increase of native 60S subunits induced by anisomycin. Our results imply that the increse of 60S subunits induced by anisomycin may be helpful in estimating the amount of initiating mRNAs in the cell.


Reconstitution of bovine procarboxypeptidase A-S6 from the free subunits. The three subunits I, II, and III of bovine procarboxypeptidase A separated by reversible dimethylmaleylation can reassociate to form the reconstituted complexes I + II, I + III, and I + II + III. Since the association II + III is not possible, subunit I appears to play a central role in the formation of the complex. It is suggested that subunit I possesses two independent and specific sites for the recognition of subunits II and III. The liberation of subunit I from any of the complexes was observed to increase its activability, although to a lesser extent than predicted by assays carried out with the succinylated protein. By contrast, the bound form of subunit II was activated faster than the free form. The potential activity of the bound form and the activity of the preformed endopentidase were also higher, suggesting a conformational change induced by association. This suggestion was fully supported by the observed modifications of the heat stability and intrinsic fluorescence spectrum of the subunit resulting form association.


Distinct properties of uridine transport systems in growing, quiescent and serum-stimulated hamster embryo cells. The kinetics of uridine uptake in growing, quiescent and serum-activated hamster embryo cells are investigated. The maximum velocity of uridine uptake in growing hamster embryo cells, is lower than in the methylcholanthrene transformed hamster cell line (MCT). This kinetic constant is further reduced in quiescent cells. The Km values in growing and in quiescent hamster embryo cells, as well as in MCT cells are of the same magnitude. Distinct alterations in the pattern of inhibition by nitrobenzyl 6-mercaptoinosin (NBMI) are detected as growing hamster embryo cells become quiescent. In quiescent cells the maximum level of inhibition is lower and the apparent Ki value for the inhibition is much higher. These changes are due to the lower apparent K'm values of NBMI-bound carriers and to the slower rate of formation of the carrier-inhibitor complex. The changes in the kinetic properties of the carriers are partly reversed by serum-activation. The number of inhibitor binding sites (i.e. nucleoside carriers) does not increase by serum-stimulation of quiescent cells (0.36 and 0.34-10(5) sites/cell in quiescent and serum-stimulated cells, respectively). It is implied that the reduction in uridine transport in quiescent cells is probably due to changes in the turnover of the carriers. These changes may be connected with the observed alterations in the properties of carriers or their immediate environment in quiescent cells.


Induction and repair of strand breaks and 3'-hydroxy terminals in the DNA of mammalian cells in culture following gamma-ray irradiation. DNA was isolated in a fairly pure and intact state from cultured mouse leukaemia cells (L5178Y) after gamma-ray irradiation using a hydroxyapatite column chromatography method, and analysed further by sucrose gradient centrifugation or DNA polymerase (EC 2.7.7.7, enzyme A of Klenow from Escherichia coli) assay. Irradiation of the cells induced single- and double-strand breaks in the DNA with an efficiency of 100 eV/break and 1300 eV/break, respecitvely. Approximately 50% of the single-strand breaks were estimated to be those arising from allali-labile lesions. A linear, dose-dependent increase was found in the template activity of the DNA, indicating the induction of 3'-OH terminals by gamma-irradiation. Post-irradiation incubation of the cells in serum-free medium allowed the majority of the breaks to rejoin within a few hours. Repair of the alkali-labile lesions was, however, found to be much slower than that of "actual" single-strand breaks. A slight increase of the DNA template activity was found during the period of post-irradiation incubation. The reason for the increase is discussed.


Lack of fatty acid specificity in the lipolysis of oligo and polyunsaturated triacylglycerols by milk lipoprotein lipase. Native soybean and rapeseed oils and native and rearranged cod liver and peanut oils were subjected to partial hydrolysis with milk lipoprotein lipase and the fatty acid composition and molecular association in the substrates and lipolysis products were determined. In both native and rearranged oils the lack of significant differences in the fatty acid composition and molecular association between the residual and total triacylglycerols suggested that all triacylglycerols were attacked by the lipoprotein lipase at about the same rate. Any enrichment of a specific fatty acid in the diacyl- or monoacylglycerol products of a native oil generally reflected the preferential association of the fatty acid with the 2-position, and to a lesser extent the sn-3-position of the glycerol molecule and was accompanied by a decreased level of the corresponding free fatty acid product. In general, the products of the rearranged oils closely resembled the original triacylglycerols in the fatty acid composition. It is concluded that lipoprotein lipase does not show any detectable specificity for the unsaturated and polyunsaturated fatty acids with double bonds located at carbons 3 to 19 from the carboxyl end of the fatty acid molecules. These findings are compatible with the possible binding of the substrate to lipoprotein lipase through atoms involved in the acyl ester groups of the triacylglycerol molecules.


Isolectins from soybean (Glycine max).

Isolectins from soybean (Glycine max). The major lectin in seeds of a soybean cultivar (Glycine max cv D68-127) has been purified to apparent homogeneity by hydroxyapatite and DEAE-cellulose chromatography. In the latter, the behavior of the lectin was similar to that of the minor isolectins previously described in other soybean cultivars. Molecular weights of 92 000 for the molecule and 23 000 for the subunits were determined by gel filtration and sodium dodecyl sulfate-gel electrophoresis; these are smaller than those previously reported for the major lectin in another soybean variety. Hemagglutination by the lectin was inhibited specifically by N-acetyl-D-galactosamine and galactose-containing sugars.


[Detection and preliminary characterization of a particular estrogen-binding protein in the liver of male rats]. Properties and isolation possibilities of an estradiol (E2) binding protein from male rat liver cytosol as possible estrogen receptor are studied. The protein is found to differ considerably in a number of characteristics from well-known receptor and non-receptor rat proteins, specifically binding estrogen. Equilibrium constant of E2-protein interaction is 1-10(8) M-1, the concentration of protein binding sites is 1.3 million per cell. Processes of E2 association with protein and the complex dissociation proceed with a very high rate. E2 and, at lesser degree, estrone, testosterone and 5-alpha-dihydrotestosterone compete for binding sites of protein with 3H-E2. Progesterone, corticosterone and a synthetic estrogen, hexestrol, denot compete. The protein studied is thermolabile and sensitive to the effect of pronase and sulfhydryl reagents. Characteristics of the protein are as follows: sedimentation coefficient--3.6S; Stockes' radius--23--25 A; friction coefficients ratio--1.05--1.12; molecular weight--36000--39000. The protein is not revealed in the liver of female rats. Ammonium sulphate precipitation, gel filtration and ionic exchange chromatography made possible to obtain 50-fold purified protein preparation.


[Kinetics of fibroblast spreading].

[Kinetics of fibroblast spreading]. For normal mouse fibroblasts four stages of their spreading in vitro are distinguished: the spherical cell stage; the stage of early appearance of processes, Lamellae formation; the stage of maximal cell spreading. Measurements of the duration of every stage were performed by means of time-lapse microcinematography under phase-contrast microscope. It is proved that the first and second stages are elementary ones of Puasson's kinetics and the following ones are complex stages of the same kinetic model. The mean time at these stages is respectively: 25+/-3.2, 12.5+/-1.5; 123+/-8; 162+/-25 minutes.


Alterations in cell free brain protein synthesis following ethanol withdrawal in physically dependent rats. The effects of ethanol withdrawal were determined on cell free brain protein synthesis in physically dependent rats. Following the development of physical dependence, ethanol abstinence for 24 h resulted in decreased protein synthesis in cerebral tissue. The observed inhibition of [14C]leucine incorporation into protein was found to be reversible after 7 days of ethanol withdrawal. Although the ribosomes from control, ethanol-treated and ethanol-withdrawn animals were highly responsive to polyuridylic acid stimulation, the ribosomes from the control group consistently exhibited higher activity. The determination of protein content of the ribosomal fraction showed a significant increase following ethanol administration and was further enhanced by ethanol abstinence. The results suggest that ethanol-induced changes at the ribosomal level may result in defective association of mRNA causing depression of brain protein synthesis.


Inactivation of Clostridium haemolyticum toxic fluids and their antigenicity. One hundred fifty-one isolates of Clostridium haemolyticum were examined for consistent toxin production following repeated serial transfers in laboratory media. Most of these isolates produced only small amounts of toxic materials and serial transfers appeared to reduce toxigenic characteristics. Eleven of the isolates consistenly produced measurable  amounts of toxic materials. One of these isolates was used for production of toxic fluids that were concentrated by lyophilization and reconstitution to a smaller volume or by precipitation with ammonium sulphate followed by dialysis against water and glycerol. Known amounts of these substances were inactivated with formalin, heat, beta-propiolactone, ultra-violet irradiation and glutathione. The resulting toxoids were inoculated into guinea pigs and most were judged to be nonimmunogenic because the animals were unable to resist dermal challenge. Toxic materials with added glycine were inactivated with formaldehyde as readily as those without the amino acid but the resulting toxoids were immunogenic while those prepared without the amino acid were not.


Fatty acid utilization by L1210 murine leukemia cells. L1210 murine leukemia cells grow in an ascites plasma that contains lipids, including 0.62 +/- 0.046 (S.E.) MICRONEq free fatty acid per ml. in vitro incubations demonstrated that isolated L1210 cells readily utilize free fatty acid that is added to the incubation medium. When the cells were incubated with albumin-bound [1-14C]palmitate, about 12 times more radioactivity was incorporated into cell lipids than was oxidized to CO2. Triacylglycerols contained 1.5 to 4 times more radioactivity than phospholipids, and from 48 to 69% of the phospholipid radioactivity was recovered in the choline phosphoglycerides. [1-14C]Palmitate utilization increased as the fatty acid concentration of the medium was raised, the largest increase occurring in the triacylglycerol fraction. Palmitate utilization also was increased by the presence of carbohydrates in the medium, their effectiveness (in descending order) being glucose, mannose, galactose, fructose, and glycerol. By contrast, ribose did not produce any stimulatory effect. During a 1-hr incubation, between 82 and 87% of the [1-14C]palmitate that was taken up remained as palmitic acid. From 8 to 15% was elongated to stearate, and only 2 to 3% was desaturated to palmitoleate and oleate. Based upon the lipid content, growth rate, and palmitate utilization rate of the cells, it appears that a major portion of the lipid requirements of the L1210 cell may be supplied by the fatty acid contained in the ascites plasma. In addition, our results suggest that most of the saturated fatty acid taken up is incorporated into cell lipids without structural modification.


Morphological evidence for an antimitochondrial action by methylglyoxal-bis(guanylhydrazone). Exposure of cultured leukemia L1210 cells to 0.1 micron methylglyoxal-bis(guanylhydrazone) resulted in a concentration-dependent inhibition of cellular proliferation, beginning after about 1 to 2 generation times (12 to 24 hr). Ultrastructural examination of the cells treated at and above 1.0 micron concentrations of drug for 24 hr revealed unifrom damage to mitochondria. The basic lesion involved extensive swelling of the mitochondrion, a deterioration and eventual loss of cristae, and a decrease in the matrix density. This damage preceded growth inhibition by about 12 hr and did not immediately affect cell viability as detected by trypan blue dye exclusion. Whether these findings are related to the known actions of the drug on polyamine metabolism is not clear at present.


Changes in the morphology of ribosomes in uterine epithelial cells under various hormonal conditions. The ultrastructural morphology of "free" cytoplasmic ribosomes of rat uterine epithelial cells was studied during diestrus, estrus, after ovariectomy, and after estradiol-17 beta administration to rats that were ovariectomized 1 to 25 weeks before hormone treatment. A change in size and contrast of ribosomes was observed concomitant with a transition from pre-existing monosomes to polysomes depending on the dose of estradiol and its route of application. In 3 weeks ovariectomized rats these changes in ribosomal granules take place at approximately the same time (30-45 min) when synthesis of "induced protein" was described biochemically. The morphological events after estradiol administration are discussed with respect to a primary site of estrogen action.


The primary structure of rabbit beta-globin mRNA as determined from cloned DNA. The rabbit beta-globin DNA insertion of the hybrid plasmid PbetaG1 (Maniatis et al., 1976) was sequenced by the method of Maxam and Gilbert (1977). A sequence of 576 nucleotides was determined and verified by pyrimidine tract analysis of double-stranded DNA, synthesized in vitro starting from beta-globin mRNA. The derived sequence is in complete agreement with previously reported partial mRNA sequencing data and with the predictions from the primary structure of the protein. Moreover, the globin DNA insertion is missing only 13 nucleotides corresponding to the 5' terminal sequence of the mRNA. The rabbit beta-globin mRNA consists of a coding region of 438 nucleotides, flanked by a 5' noncoding region of 56 nucleotides (including the initiation codon AUG but not the 7-methyl-guanine of the "cap structure") and by a 3' noncoding region of 95 nucleotides (including a UGA termination codon). The features of the mRNA sequence are discussed with specific attention to the selective use of particular codons, the probable existence extensively base-paired segments at the 5' terminal region and the ribosome binding site. The faithful representation of beta-globin mRNA in the PbetaG1 DNA insertion establishes the validity of used cloned DNA, initially derived from double-stranded DNA transcripts of mRNA, for studying the structure of eucaryotic genes.


Post-transcriptional regulation of ribosome accumulation during myoblast differentiation. The synthesis, accumulation and stability of rRNA were examined in embryonic quail myoblasts differentiating in cell culture. Quail myoblasts initially divide rapidly in culture, and accumulate 28S and 18S rRNA and ribosomes at a rate which maintains a constant ribosome content during cell division. After these myoblasts fuse, cell division ceases and ribosomes accumulate in fibers, but at a reduced rate which is only one fourth that in dividing myoblasts. Measurements of rRNA stability by 3H-methyl-methionine pulse-chase analysis show that 28S and 18S rRNA formed by fibers turn over with half-lives of 45 hr, and rRNA formed by myoblasts remains stable until fusion and then also turns over in fibers. Turnover of rRNA in fibers accounts for only half the reduction in ribosome accumulation following myoblast fusion. Measurements of the incorporation of 3H-adenosine into rRNA and ATP pools show that the rates of synthesis of rRNA precursor do not decrease after myoblast fuse, but half the rRNA molecules synthesized by fibers are degraded during processing. Degradation of rRNA during processing reduces the rate of formation of 28S and 18S rRNA, and together with rRNA turnover quantitatively accounts for the reduced rate of ribosome accumulation in fibers.


Relationship between nuclear and polysomal RNA populations of Achlya: a simple eucaryotic system. The relationship between hnRNA and mRNA in the water mold Achlya has been investigated in several ways. Analysis of the nuclear and polysomal poly(A) RNA by sucrose density gradient centrifugation under denaturing and nondenaturing conditions showed that the populations have indistinguishable size distributions. The number average sizes were calculated to be 1150 nucleotides for nuclear and 1140 nucleotides for polysomal poly(A) RNA. Selective inhibition of rRNA synthesis was used to investigate the size distribution of hnRNA without regard to poly(A) content. Very little hnRNA was observed which sedimented more rapidly than polysomal poly(A) RNA. Hybridization experiments in which an excess of nuclear DNA was reacted with 3H-poly(A) hnRNA or 3H-poly(A) mRNA showed that both populations contain repetitive transcripts (9-10%) as well as single-copy transcripts (44%). Analysis of hybrids on hydroxyapatite in the presence of 8 M urea demonstrated that the poly(A) RNA complementary to repetitive DNA sequence components represented a population of molecules distinct from the population complementary to single-copy DNA. The complexity of whole cell, nuclear and polysomal RNA was determined by saturation hypbridization to single-copy 3H-DNA. All three populations were complementary to essentially the same fraction of the DNA. Terminal hybridization values were 3.84, 3.76 and 3.76% for whole cell, nuclear and polysomal RNA, respectively, representing a complexity of 2.1 X 10(6) nucleotides. These data suggest that the composition of the hnRNA and mRNA populations are essentially identical. No evidence for selective turnover of any sequence component or size class within the nucleus was observed.


Immediate glycosylation of Sindbis virus membrane proteins. The mechanism by which the membrane proteins of Sindbis virus are initially glycosylated during growth of the virus in chick cells was studied. The experiments suggest strongly that the two viral glycoproteins are glycosylated before release from the polysome, and that this glycosylation involves transfer of a large 1800 dalton oligosaccharide to the polypeptide chains. The donor of the oligosaccharide is most probably a lipid.


Mammalian cells with defective mitochondrial functions: a Chinese hamster mutant cell line lacking succinate dehydrogenase activity. A mutant cell line derived from Chinese hamster fibroblasts is described which is defective in oxidative energy metabolism. Glucose is continuously required in the medium. As a result of a block in the Krebs cycle, these cells are auxotrophs for carbon dioxide and asparagine. Several experiments support our conclusion that the mutant cells lack appreciable levels of succinate dehydorgenase activity. Other components of the electron transport chain appear to be fully functional, although there is the possibility that electron transport and oxidative phosphorylation are uncoupled.


Mutations causing rapid development of Dictyostelium discoideum. A mutation affecting the speed of slime mold development has been genetically analyzed. Strain FR17 carries a recessive mutation on linkage group IV. A selection procedure for isolating more mutants of this type has been developed and new mutations have been tested for complementation. The aberrant morphology of these strains can be partially corrected by development in the presence of glucose.


A non-chromatographic radioimmunoassay of testosterone in serum. Convenient methodology based on separation of testosterone from non-alcoholic neutral steroids by means of a sulfation procedure has been developed for the radioimmunoassay (RIA) of testosterone in male and in female serum. When coordinated with our previously published non-chromatographic procedure (1) for the RIA of estrone and 17 beta-estradiol in serum all 3 steroids can be determined in the same specimen. With only minor modification (14) progesterone also can be determined. Validation of the procedure was based on: 1. agreement between results obtained using TLC and sulfation to fractionate testosterone (r=0.99; b=1.03), 2. accurate recovery of different quatities of testosterone added to serum, 3. independence of the concentration of testosterone and volume of serum used for assay, 4. low procedural blanks (1.1+/-0.7 pg), 5. low intra-assay (4.7-4.8%) and interassay (4.8-8.8%) variability and 6. correspondence of observed values for testosterone in male serum (7.00+/-2.03 ng/ml) and in femal serum (420+/-115 pg/ml) with those reported previously by others.


The occurrence of circulating immune complexes and viral antigens in idiopathic thrombocytopenic purpura. The sera of seventy-two patients with ITP were tested for their inhibitory activity on the agglutination of IgG-coated particles by RF or C1q. The majority (83%) displayed an inhibitory effect toward both agglutinators, whereas 17% were found to contain endogenous RF. A negative correlation was observed between the number of platelets and the titres of inhibitory factors. Some sera were fractionated by gel filtration. The inhibitory factors and sometimes trace amounts of IgG were distributed over several peaks eluted before monomeric 7S IgG. The IgG detected in the heavy fractions of two ITP sera corresponded to antigen-antibody complexes as shown by dissociation experiments at acid pH. In all ITP sera analysed by chromatography, DNA has been detected in the heavy fractions and appears to be the antigen of certain complexes. The sera from forty-two patients with ITP were analysed by counter-electrophoresis for the presence of viral antigens. HBs antigen was detected in twenty sera, EBV antigen in five, and adenovirus antigen in six.


Ultrasound scanning in the radiotherapy department. Apart from its use by diagnostic radiologists in the detection and staging of tumours, ultrasound scanning appears to offer particular advantages to the radiotherapist in treatment field planning. The following merits are almost self-evident: tumour, organ and body outlines are visualised, with the patient usually in the treatment position, sufficiently accurately for measurement, field planning and for checking of the treatment fields. Moreover, the safety and high patient-acceptability of the scanning technique allows reassessment of tumour morphology with early modification of the treatment regime. In certain cases, heavy reliance is now made on the information from ultrasound scanning since more conventional investigation would not allow imaging of the tumour-affected area in the treatment planes. On occasions carefully planned treatments based on conventional planning procedures have had to be modified because subsequent ultrasound scans have revealed inadequate cover of the tumour or non-optimal treatment field positioning. It would seem advisable that radiotherapy departments should acquire the expertise and personnel to ensure access to ultrasound scanning systems, both to increase the accuracy of defining the tumour-bearing area for treatment planning and to avoid methods of investigation involving invasive techniques.


Factors affecting angiotensin II concentrations in the human infant at birth. 1. A radioimmunoassay for the measurement of angiotensin II in 1 ml of plasma has been developed and used to measure angiotensin II in maternal peripheral, cord venous and cord arterial blood in 45 patients at delivery. 2. In babies delivered vaginally, cord venous and cord arterial concentrations of angiotensin II were significantly higher than maternal venous blood concentrations. There was a significant relationship between both cord venous and cord arterial concentrations and maternal concentrations of angiotensin II. 3. Cord venous concentrations of angiotensin II were significantly greater than those in cord arterial blood in babies delivered vaginally but not in those delivered by lower-segment Caesarean section. This suggests the possibility that, during labour, the placenta may contribute to foetal concentrations of angiotensin II. 4. Maternal and cord venous concentrations of angiotensin II were significantly higher in patients with hypertensive disease of pregnancy than in those who had remained normotensive throughout pregnancy. 5. Cord venous concentrations of angiotensin II increased significantly with increasing duration of the second stage of labour.


Gila monster bite: a case report.

Gila monster bite: a case report. Transient electrocardiogram abnormalities are described in a young man who was bitten by a Gila monster (Heloderma suspectum). The patient's pain subsided spontaneously without narcotics and the vascular status of his bitten extremity was monitored by Doppler examination. The patient was discharged in 24 hr after conservative management.


Origin of triploidy and tetraploidy in man: 11 cases with chromosomes markers. Sixteen triploid and one tetraploid human abortuses were studied for the origin of polyploidy using a sequential Q- and R-banding technique. Ten triploid abortuses provided informative data: one originated in the maternal first meiotic division; five apparently resulted from dispermy; two derived from an error during either the paternal second meiotic division or the first mitotic division; and the last two were of paternal origin. The results indicate that paternal factors, especially dispermy, are the predominant sources of triploidy in man. The tetraploid abortus showed duplication of both the maternal and paternal haploid sets, suggesting normal division of chromosomes and suppression of cytoplasmic cleavage at the first mitotic division. No correlation was found between the origin of polyploidy and the phenotype of the triploid abortuses, nor between the origin of polyploidy and the maternal use of oral contraceptives.


Presence of subunit structure in bovine follicle-stimulating hormone. Highly purified bovine follicle-stimulating hormone (FSH) potency 164 X NIH-FSH-S-1 by bioassay was estimated to be 210 +/- 4.2 X NIH-FSH-S-1 by radioligant-receptor assay using 125I-bovine FSH as tracer but only 120 +/- 1.8 X NIH-FSH-S-1 when 125I-human FSH tracer was used. The presence of subunit structure in bovine FSH was revealed by SDS-polyacrylamide gel electrophoresis. Furthermore, treatment of bovine FSH with 1 M propionic acid resulted in marked changes of mobilities upon polyacrylamide gel electrophoresis and elution profiles after gel filtration on Sephadex G-100 in addition to loss of biological activity by radioligand-receptor assay. After incubation, the propionic acid-treated bovine FSH recovered about 75% of the receptor-binding activity and regenerated protein bands of identical electrophoretic mobilities as the native hormone.


Does androgen influence prolactin secretion? In both intact and castrated male and female rats, administration of the A-ring reduced androgen, dihydrotestosterone (DHT), consistently failed to stimulate prolactin (PRL) secretion although it inhibited LH release and, in males, stimulated ventral prostate growth. In intact females, but not in the other types of rat, DHT actually suppressed PRL release. These findings do not support generalizations, based entirely on findings with testosterone, that both "androgens" and estrogens exert stimulatory actions on PRL secretion. The distinct stimulatory effects of testosterone and its esters on PRL secretion seem attributable, not to their androgenic actions per se, but to the ability of testosterone to form estrogenic metabolites. This ability does not appear to be shared by the "pure" androgen, DHT.


The effect of triiodothyronine on 2-deoxy-D-(1-3H)glucose uptake in cultured chick embryo heart cells. The uptake of 2-deoxy-D-[1-3H]glucose ([1-3H]DOG)by cultured chick embryo heart cells was stimulated by exposure to triiodothyronine (T3). The concentration of free T3 for half maximal stimulation of [1-3H]DOG uptake was 8.7 x 10(-10)M. Nuclear binding studies revealed that the Kd for T3 was 4.2 x 10(-10)M. The molar potencies of other thyroactive compounds in stimulating [1-3H]DOG uptake, relative to L-T3, were: 500% for 3'-isopropyl-3,5-diiodo-L-thyronine, 20% for L-thyroxine (T4), 17% for D-T3, 2.2% for D-T4, 0.6% for 3,5-diiodo-L-thyronine and less than 0.1% for 3',5',3-triiodo-L-thyronine and L-thyronine. These data suggest that cultured chick embryo heart cells may serve in the study of the mode of action of thyroid hormones.


The effects of actinomycin D, puromycin, cycloheximide and hydroxyurea on 3',5,3-triiodo-L-thyronine stimulated 2-deoxy-D-glucose uptake in chick embryo heart cells in vitro. The uptake of 2-deoxy-D-[1-3H]glucose ([1-3H]DOG) by cultured chick embryo heart cells was stimulated by L-triiodothyronine (T3). This stimulation began with the exposure to T3, rose linearly for about 8 h and reached a plateau around 24h. Actinomycin D, puromycin and cyclohexmide had no effect on the stimulated sugar uptake during the first 6h. These agents prevented the further increase in the rate of [1-3H]DOG uptake in T3-treated cultures that occurred between 6 and 24h. In the presence of hydroxyurea the uptake of [1-3H]DOG in both control and T3-treated cells was unchanged. These results suggest that some of the effects of T3 may not require new synthesis of either RNA, proteins or DNA.


A comparison of the disappearance rates of luteinizing hormone from intact and ovariectomized rats. Hypophysectomy was performed on intact female rats during the proestrous LH surge and on ovariectomized rats, and plasma concentrations of LH were measured every 5 min for approximately the next hour. The disappearance rate of LH from ovariectomized rats corresponded to an initial half-life of 23.1 +/- 2.9 min, which is within the range previously reported for this species. The disappearance of LH from intact rats, however, corresponded to an initial half-life of 13.7 +/- 0.7 min. In a second experiment, blood was taken from ovariectomized rats and from intact female rats during the LH surge. The sera were injected iv into hypophysectomized female rats (with ovaries intact) bearing chronic venous catheters, and plasma concentrations of LH were measured every 5 min for the next hour. LH from ovariectomized rats disappeared at a rate corresponding to an initial half-life of 22.7 +/- 2.2 min, while the half-life for LH from proestrous intact rats was 13.4 +/- 1.2 min. These results suggest a change in the circulating form of LH following ovariectomy, in that LH in the ovariectomized rat is cleared more slowly. Further, it appears that LH is removed from the circulation of the intact rat at a higher rate than has previously been reported.


Virilizing activities of various steroids in female rat fetuses. Virilizing activities of nineteen steroids were examined by a method measuring the abridgment of urovaginal septum length of female rat fetuses directly under microscope, following oral administration of the steroids to the mothers for 4 days during the late period of gestation. The characteristics of the virilizing activities of the steroids seemed to depend on their chemical structures. No virilizing activities were observed in progesterone, retroprogesterone, chlormadinone acetate and nandrolone phenpropionate. The introduction of 6-methyl and 17-acetoxy groups into progesterone exhibited a marked virilizing activity. With testosterone and its derivatives, the introduction of 17alpha-ethynyl group into testosterone slightly decreased the virilizing activity compared with the parent compound. On the contrary, the introduction of [3, 2-C] pyrazole ring in addition to the saturation of A-ring strikingly increased the virilizing activity. The most active virilizing steroid in this group was stanozolol followed by oxymetholone, methyl-testosterone and dimethysterone. Testosterone propionate was assumed to be less active than methyltestosterone by this route. With 19-nortestosterone derivatives, the virilizing activities of compounds with 17alpha-ethynyl group were moderate, but the presence of 17alpha-ethyl group caused a marked increase of virilizing activity. While, nandrolone phenpropionate with long side chain at C-17 exhibited no significant virilizing activity. The present results show the possibility of the evaluation on a potential virilizing activity of compounds in the female fetus, and also suggest that a dossociation between the virilizing activity and the androgenic activity may exist among some compounds.


Ovulation in light-estrous rats induced by darkness. Adult female rats show continual vaginal cornification and cease ovulation a few weeks after they are exposed to continuous lighting (light-estrous rats). When these rats were placed in the darkness for 10 hr, 80% of the animal ovulated approximately 46 hr later. Peripheral LH increased to a small peak immediately after placing in darkness concomitant with a decrease in pituitary LH content; a large peak, 20 times higher than the basal LH level, was observed at 20 to 22 hr. Progesterone concentration in ovarian vein blood remained at extremely low levels while estrogen levels tended to rise after small LH peak. This estrogen rise appeared to play an important role in inducing the main LH peak. Simulation of the small LH peak by low doses of exogenous LH succeeded in inducing ovulation of light-estrous rats in similar fashion to the exposure of light-estrous rats to 10-hr darkness. Therefore, the small amount of LH secretion observed after the initiation of the darkness-treatment may be considered as a trigger for the whole sequence of hormonal changes leading to ovulation.


Interferon-induced antibody suppression: a selective effect on high density, late responding precursor cells. Mouse spleen cells have been fractionated into three subpopulations by density gradient centrifugation and the effect of interferon on the ability of each fraction to generate an antibody response in vitro has been examined. The results show that only the antibody-forming cell precursors (AFCP) of the high density, late responding fraction are suppressed by interferon. The presence of interferon had no effect on either the number or the mean size of clones of antibody-forming cells in cultures of the low and medium density fractions. Interferon-mediated suppression of the response of high density precursors was due to a decrease in the number but not the size of responding clones. These results suggest that interferon suppresses antibody responses by affecting the degree to which high density AFCP can becoming activated rather than the degree to which precursors proliferate.


Comparison of the production rates of bacteria in the rumen estimated by using labelled live and formaldehyde treated mixed bacterial cells. The bacteria production rates in the rumen have been estimated by injecting 14C- and 35S-labelled mixed rumen bacteria, either live or killed by treatment with formaldehyde, into the rumen and applying isotope dilution technique. The rate of bacteria production when estimated by using either live- or dead-(protected-)labelled bacterial cells were comparable.


Preferential neurotoxicity of pentobarbital on nerve and glial cells in culture. The effect of pentobarbital was studied in a mixed population of nerve and glial cells dissociated from brains of 7-day chick embryos and maintained in culture. Pentobarbital-Na was added in various concentrations ranging from 5 X 10(-5) M to 1 X 10(-3) M. The neuronal density was monitored by counting the neurons, neuronal identity was established by staining for Nissl Bodies and acetylcholinesterase. Over a culture period of 3 weeks, it was found that the barbiturate exerts a preferential dose-dependent cytotoxic effect on neurons.


Changes in brain dopamine levels and aggressive behavior with aging in 2 mouse strains. The genetic programming of brain monoamine changes with aging show remarkable differences in 2 mouse strains. A marked increase in dopamine occurred in 32-week-old grouped ICR mice and the males showed intense irritability and aggressive behavior. Brain amines changed only slightly in old C57BL6J mice and behavior remained benign. Old females showed similar amine changes but aggresive behavior did not occur in either strain.


Incidence of antisperm antibody levels and granulomas in men. Blood samples were collected from 77 men at the time of vasovasostomy and tested for the presence of antisperm antibodies. More men with granulomas had sperm-immobilizing antibodies than did those without granulomas.


Publicity and the public health: the elimination of IUD-related abortion deaths. Widespread publicity in the mass media about the dangers of leaving an IUD in place in a pregnant uterus was apparently more effective than traditional scientific publication and drug package inserts in getting doctors to remove devices from pregnant patients. This suggests that such publicity could be effective in improving clinical practice and the public health in other instances, such as getting doctors to prescribe and women to request birth control pills with lower doses of estrogen, and persuading women to obtain early rather than the riskier midtrimester abortions.


The management of premature ejaculation. The problems associated with the treatment of premature ejaculation are discussed. The types of men who present with premature ejaculation are described. Behavioural procedures and the role played by clomipramine (Anafranil) in the treatment of the condition are mentioned, and a rational approach to treatment is presented.


[Considerations on the diagnostic and therapeutic approach to hypertrophic subaortic stenosis (author's transl)]. Several physiopathological, diagnostic and therapeutic considerations have arisen from the observation of an operated case of hypertrophic subaortic stenosis associated with mitralic insufficiency and fibrosis of the interventricular septum. Keeping in mind the variability of the clinical pictures and the functional and anatomical factors which determine the clinical picture of the hypertrophic subaortic stenosis, it is concluded that a careful, unbiassed, clinical approach is necessary to determine the therapeutic procedure in each individual case.


Relation of food consumption to cancer mortality in Japan, with special reference to international figures. The present study was designed to examine the epidemiological association of food consumption with cancer mortality in Japan, if any, in comparison with similar examinations in developed countries including Japan, in a search for dietary factors in cancer etiology. Whereas food consumption patterns in Japan was believed to be specific among developed countries, this study revealed that the correlation matrix among major foods both for international and Japanese data made it possible to categorize these foods into two groups with some similar patterns, since there should be observed a positive or negative correlation for each pair of foods. The patterns for correlation of food consumption to cancer mortality in Japan were found to be considerably different from those in developed countries, and this suggested that the epidemiological association between the two in Japan, if any, could be specifically evaluated from that in develop countries. The urban-type region for food consumption in Japan, however, indicated a possible westernization for the relation of food consumption to cancer mortality as well as for food consumption patterns, whereas the traditional Japanese region for food consumption did not indicate any similarity with westernization for the relationship between food consumption and cancer mortality, as well as for food consumption patterns. The above findings also suggested that there might be a possible significance for the regionalization of Japan in such studies, and that the urbanization of food consumption patterns in Japan would show that this country has a similar pattern of association between food consumption and cancer mortality as observed among developed countries in Europe and/or North America.


Effect of the inoculum size of cells on the maintenance of diploidy in cultured liver cells of the rat. In culture, a cloned rat liver cell line, J-5-2, exhibited a high diploidy for 200 days after the last cloning (diploid line) but, thereafter, pseudodiploid cells gradually increased in number (pseudodiploid line). These diploid and pseudodiploid lines were inoculated at various sizes, and chromosome analysis was performed for 75 days of serial passages. Diploid line showed an increase of pseudodiploid cells at a large inoculum size. On the other hand, more than 80% of the cells examined maintained the diploid karyotype at a small inoculum size. Pseudodiploid line showed an increase of pseudodiploid cells at a large inoculum size and of diploid cells at a small inoculum size. These pseudodiploid cells contained three types of marker chromosomes, in which number 1 chromosome was found to be involved by the G-banding methods. The saturation density of the pseudodiploid line was much higher than that of the diploid line, and plating efficiency of the diploid line was also significantly higher than that of the pseudodiploid line, although the populating doubling time of these two lines was almost the same. Possible mechanisms for the effect of different inoculum sizes on the incidence of diploid cells and pseudodiploid cells are discussed.


Cell-mediated cytotoxicity in vitro of human lymphocytes against a cervical cancer cell line. Peripheral blood lymphocytes from patients with uterine cervical cancer were tested against a cervical cancer cell line by micro-cytotoxicity assay. In stage O, high degree of cytotoxicity was observed but it decreased with progression of disease. In stage IV and recurrent cases, cytotoxic activity was negligible. Lymphocytes from healthy controls and myoma patients were not cytotoxic against target cells. On the other hand, lymphocyte response of phytohemagglutinin as a nonspecific T-cell activity was as high as the of healthy control in stage O, but the response decreased in stages I to IV and recurrent cases. In stages I to III, several cases showed cytotoxic activity but decreased response to phytohemagglutinin.


Genetic analysis of a strain of mice plateaued for litter size. A strain of mice (S1) was successfully selected for large litter size for 31 generations, increasing the mean by 4.2 young per litter. After generation 31, there was no further progress and it was concluded that a selection plateau had been reached. Realized heritability decreased during the course of the experiment from 0.16+/-0.06 for the first 15 generations to 0.00+/-0.03 for generations 30 through 45.--In order to explore the nature of the selection plateau, the following groups were derived from line S1 at generation 34 or 35: Upward selection with inbreeding (SF), random (relaxed) selection (SO), and downward selection (SR). Selections were carried out for 10 to 11 generations. The means of SO and SF were similar to those of S1, ruling out any major effect of natural selection or overdominance. SR decreased, the mean averaging 2.3 young per litter below that of S1 during the last three generations. The fact that SR responded to selection indicates that genetic variance was still present in the plateaued population. The SF sublines were crossed when the inbreeding was 95% and a new line, SX, was formed. SX was maintained for three generations and the difference of +0.7 young per litter above the contemporary generations of S1 was significant. The results from this experiment suggest that the selection plateau in line S1 was caused by reduction of additive genetic variance to a very low level. Some nonadditive genetic variance remained, however, and was attributed to recessive alleles at low frequency. In agreement with results reported by Falconer (1971), inbreeding with selection followed by crossing of the inbred sublines proved to be effective in overcoming a selection plateau in litter size.


Determination of tissue thromboplastin activity. The one-stage prothrombin time test for tissue thromboplastin activity was evaluated using the correction method. A strong influence of the intrinsic system was seen depending on the clotting time and the type of tubes. This test was unsuitable for quantitative comparison of thromboplastin activity of different preparations. Subsequently a two-stage assay for human thromboplastin is described using purified human factor VII, artifically prepared factor VII reagent, and a phospholipid suspension. The correction method, applicated to this two-stage assay, resulted in a rectilinear dose-response curve when the clotting times of a thromboplastin dilution series were plotted against the reciprocal of the concentrations. Using this test system it could be shown that thromboplastin from porcine tissue can activate human factor VII quite well, while that from bovine tissue cannot.


[Effects of secretin on renal functions in the dog]. In anesthetized mongreal dogs, the intrarenal arterial (0.2 approximately 1.0 unit/kg-min) and the intravenous infusion (0.4 approximately 2.0 unit/kg-min) of secretin caused dose-dependent increase of RBF, accompanied by decreases of the calculated afferent arteriolar resistance (Ra) and efferent arteriolar resistance (Re), but produced no significant effect on GFR, urine flow, electrolyte excretion, osmolar clearance and free water reabsorption. The distribution of cortical blood flow was examined using the radioactive microsphere technique. The intrarenal infusion of secretin (1.0 unit/kg-min) increased renal cortical blood flow in the juxtamedullary area much more than in the superficial area, shifting the blood flow from the outer to the inner zone. Simultaneous intrarenal infusion of secretin (1.0 unit/kg-min) and glucagon (0.5 microng/kg-min) produced increases in GFR, urine flow and electrolyte excretion to a lesser degree than those induced by glucagon alone, whereas the increment in RBF and the decreases in Ra and Re were almost to the same degree as those caused by secretin alone. The present results indicate that secretin produces the dilation of afferent and efferent arterioles, resulting in an increase in RBF, with no change in GFR and urine flow, and that the effects of glucagon on renal functions are masked by secretin mainly through the effects of renal hemodynamics.


[Pharmacological studies of 2-(5H-(1)benzopyrano[2,3-b]pyridin-7-yl)propionic acid (Y-8004). (3) Its interaction with anti-inflammatory agents]. Interactions of Y-8004 with anti-inflammatory agents were examined in the carrageenin foot edema and adjuvant induced arthritis tests. The combined administration of hydrocortisone with Y-8004 or other acidic non-steroidal anti-inflammatory agents resulted in a synergistic inhibition of edema. The therapeutic effect of a combination of hydrocortisone and Y-8004 was found to be greater than the effect produced by each of the component agents at corresponding doses in the adjuvant induced arthritis test. Y-8004 also maintained the therapeutic effect of prednisolone by alternative administration in succession to prednisolone therapy as well as indomethacin. On the other hand, the combined effect of acetylsalicylic acid with Y-8004 was antagonistic at the combined ratio in 25 to 1, but synergistic at the combined ratio in 100 to 1. Similar results were obtained in combinations of Y-8004 and indomethacin. The acute toxicity of Y-8004 in rats was potentiated by the combined administration of hydrocortisone or acetylsalicylic acid. The toxicity of indomethacin was, however, antagonized by a combined administration with acetylsalicylic acid as well as the anti-inflammatory activity of indomethacin. These results suggest that Y-8004 may make feasible a reduction in dosage or a withdrawal of the steroid prescription. Antagonism between non-steroidal anti-inflammatory agents has yet to be established.


[Pharmacological study on 5-(o-chlorophenyl)-1-methyl-7-nitro-1,3-dihydro-2H-1,4-benzodiazepin-2-one (ID-690), with special reference to the effects on motor systems]. Effects of ID-690 on motor systems were compared with those of clonazepam, diazepam and nitrazepam. ID-690 exerted muscle relaxant action in the rotarod method using rats and mice; this action was almost equal in potency to clonazepam and nitrazepam and more potent than diazepam. Pretreatment with ID-690, clonazepam and nitrazepam increased the sleeping time of mice under thiopental anesthesia to the same degree, whereas diazepam produced a lesser effect. ID-690 was almost equal in potency to diazepam and nitrazepam in protecting against oxotremorine-induced tremor in mice, and approximately 10 times as potent as clonazepam. The anticonvulsant action of ID-690 was similar to that of clonazepam. These benzodiazepines effectively augmented the dorsal root reflexes, while showing no effects on the ventral root reflexes. Rigidity in rats due to anemic decerebration was not affected after intraduodenal administration of these drugs, while phasic augmentation of the rigidity by mechanical stimulation of the hind limb was clearly depressed. These drugs had no effects on the neuromuscular junction. From these results, it is concluded that ID-690 has a wider pharmacological spectrum than clonazepam, is almost equal in potency to nitrazepam and is more potent than diazepam.


[Analgesic effect of pentazocine and its action on nociceptive afferent pathway]. Nociceptive stimulus was applied to the skin of adult cats by pinching with a serrated forceps or by radiant heat with Pain meter. This stimulation caused motor or emotional responses such as movements of the head and trunk, vocalization, escape and attack. After the administration of pentazocine, these responses disappeared and the animals behaved normally. Analgesic action appeared approximately 15 min after the administration and lasted more than 90 min. Effects of pentazocine on pain-afferent pathways were studied and the evoked potential was recorded by tibial nerve stimulation. Though pentazocine did not influence the evoked potential recorded from somatic sensory area I and mesencephalic central gray, the evoked potential in pre-central association area, nucleus centralis lateralis, nucleus suprageniculatus-limitans and reticularis pontis caudalis was reduced by pentazocine.


[Central effects of beta-phenylethylamines. (8). Increase in spontaneous motor activities of mice caused by intracerebrally administered metaramino]. Metaraminol (MA) (40, 80 and 160 microng) was injected i.c. into mice and spontaneous motor activity (SMA) measured by photo-cell counters method was found to increase 30 min after the injection. Ninety min after, the SMA was restored to the saline treated control. MA (80 microng i.c.) was also injected into isocarboxazide (Iso) pretreated mice and the SMA markdly increased as compared with the Iso+saline treated group or tween+MA treated group. When MA was injected i.c. into alpha-methyl-p-tyrosine (alpha-MT) pretreated mice, the SMA significantly increased as compared with that of the alpha-MT+saline treated group, but there was a decrease as compared with that of the tween+saline or tween+MA treated group. In alpha-MT treated mice. L-Dopa restored the hyper-motor activity of animals treated with MA. Diethyldithiocarbamate (700mg/kg i.p.) had no influence, whereas haloperidol markedly blocked the hyper-motor activity induced by MA. The hyper-motor activity induced by MA in mice raised the question of a possible role of noradrenaline and dopamine in the mediation of this action.


[Study of intracranial dynamics by applying a water-soluble contrast medium, N-methylglucamine iothalamate, to the dog brain]. The water-soluble contrast medium, N-methylglucamine iothalamate (NMGI), when injected in a dose of 1 ml into the cerebral parenchyma space of dogs (Feldberg's method), diffused within the lateral ventricle at a constant rate of flow against the nerve fibers running therein. Such was recorded by X-ray television and 16 mm cinecamera. Injection of the same dose into the subarachnoid space, however, did not produce these phenomena. Differences in the mode of transfer from brain to heart as the result of three different sites of application (ventricle, parenchyma and subarachnoid space) were investigated using 131I labeled NMBI, the determination of radioactivity being made by two scintillation detectors situated at the head and the heart. The determination of RI activity revealed that the above mentioned three areas of brain have their own characteristic pattern of attenuation from brain to heart, particularly in the case of subarachnoid application. Clonic convulsions after intracranial administration of NMGI in dogs occurred when NMGI was given into the parenchyma but not when given into the ventricle.


[Effects of adenosine compounds of the vascular bed and effects of dilazep, theophylline, and indomethacin on blood flow changes of the postocclusive renal vessels]. In anesthetized dogs, intrarenal arterial injections of adenosine (Ads) and adenosine 5' monophosphate (AMP) caused transient, vasoconstrictions, but those of adenosine 5' diphosphate (ADP) and adenosine 5' triphosphate (ATP) caused vasodilations. All of these agents produced marked vasodilations in the mesenteric and femoral vascular beds. An i.v. injection of dilazep (10--30 microng/kg) enhanced significnatly the effects of Ads and AMP at these three vascular beds, whereas this compound had no effects on results with ADP, ATP, norepinephrine and angiotensin. Administration of theophylline (10--30 mg/kg) given intravenously attenuated Ads and AMP actions, but had no effects on the other four agents. Renal vasoconstrictions induced by Ads. AMP, norepinephrine and angiotensin were followed by slight vasodilations which were abolished by indomethacin (2--5 mg/kg) given intravenously. Based on these findings postocclusive renal vascular responses were examined. The responses were divided into two phases. Phase1 was the initial decrease and phase2 was the successive gradual increase in renal blood flow (RBF). Phase 1 was significantly potentiated by dilazep, but inhibited by theophylline. Phase2 was abolished by indomethacin. These results indicate that the postocclusive renal vascular responses may be mediated through Ads and/or AMP and prostaglandins released from the kidney.


The effect of diazepam, chlorpromazine and amobarbital on the contingent negative variation. The effects of diazepam (5 mg), chlorpromazine (CPZ, 12.5 mg) and amobarbital (100 mg) on the contingent negative variation (CNV) at Cz and Oz were studied in groups of 10 subjects each. Amobarbital and placebo were given by the double-blind crossover method. Two kinds of experimental paradigms were used: Click (warning stimulus, S1)--flashes (imperative stimulus, S2)--and click--electrical stimulation--motor response. The results obtained were as follows; 1) CNV amplitudes were decreased significantly by administration of diazepam only at Cz when S2 was flashes and at both Cz and Oz when S2 was electrical stimulation. 2) CPZ-induced effects were of either augmentation or decrement in CNV amplitudes depending on the subject and on the modality of S2. Involvement of dose-dependent factor was suggested. 3) Amobarbital and placebo did not give any significant changes to the CNV. 4) Significant correlations between CNV amplitudes at Cz and Oz were found before drug administration and even after taking drugs exclusive of diazepam. Its decremental ratio from Cz to Oz was approximately 0.6 to 0.8. The correlation coefficient became to be insignificant after taking diazepam only when S2 was flashes.


Plasma free fatty acids in pregnant insulin-independent Natal Indian diabetics. A study was undertaken in Natal Indians to determine the insulin secretory response and the comparative degree of free fatty acidaemia in normal and insulin-independent diabetic pregnant women. The fasting plasma FFA and glucose levels were found to be substantially greater in the diabetic subjects. The pattern of plasma FFA and glucose response to exogenous insulin was similar in both groups. Endogenous insulin produced a similar FFA response, but a markedly obtunded blood sugar response occurred among the diabetics despite adequate plasma insulin levels. The significance of the differential effect of endogenous insulin on FFA and glucose metabolism in pregnant insulin-independent Natal Indian diabetics is discussed.


Possible localization of Gc-System on chromosome 4. Loss of long arm 4 material associated with father-child incompatibility within the Gc-System. A mentally retarded girl with a sporadically occurring B/F translocation was reexamined with new banding techniques. Chromosome material from the long arm of chromosome 4 was inserted into the long arm of chromosome 20. The segment 4q11 leads to q13 was lost. The formerly reported abnormal segregation of the Gc-system was verified. The localization of the Gc-locus on the lost segment cannot be ruled out.


Biological activities of lipopolysaccharides and lipid A from Rhodospirillaceae. The lipopolysaccharides and free lipid A from several strains of Rhodospirillaceae were assayed comparatively with those of Enterobacteriaceae in a number of biological tests. Free lipid A's from Rhodopseudomonas gelatinosa and Rhodospirillum tenue exhibited strong serological cross-reactions with each other and with free lipid A from Salmonella. Lipid A's from Rhodopseudomonas viridis and Rhodopseudomonas palustris, although cross-reacting with each other, did not do so with either the lipid A of R. gelatinosa or R. tenue or with that of Salmonella. The presence or absence of the above cross-reactions agreed with corresponding similarities or differences in the chemical structure of the lipid A preparations. The lipopolysaccharide of R. gelatinosa was highly toxic for adrenalectomized mice and pyrogenic for rabbits; however, it exhibited no anti-complementary activity. The activity of the R. tenue lipopolysaccharide was very low in both the lethality and pyrogenicity tests. Its corresponding free lipid A also exhibited low pyrogenic activity; however, its lethal toxicity for adrenalectomized mice was considerably higher than that of the intact parent lipopolysaccharide. Both intact lipopolysaccharide and, unexpectedly, the free lipid A exhibited no anti-complementary activity. The lipopolysaccharides of R. viridis and R. palustris were virtually nontoxic for mice and nonpyrogenic for rabbits. Both lipopolysaccharides were highly potent in their interaction with complement. They therefore represent the first example of nontoxic lipopolysaccharides exhibiting high anti-complementary activity.


Protective effect of vaccines on Mycoplasma pulmonis-induced respiratory disease of mice. Mice inoculated intranasally with either a virulent or an avirulent strain of live Mycoplasma pulmonis were resistant to respiratory disease induced by a subsequent intranasal challenge with virulent organisms. Similarly, mice inoculated intravenously with the virulent strain were resistant to intranasal challenge with the same strain. In contrast, mice inoculated intravenously with avirulent M. pulmonis were not resistant to intranasal challenge with the virulent mycoplasma strain. Studies on mice inoculated intravenously with the two strains of M. pulmonis indicated that persistance of mycoplasmas in the respiratory tract may be important in inducing resistance to intranasal challenge with M. pulmonis. These observations, together with the lack of correlation between the level of serum antibodies and resistance to M. pulmonis-induced respiratory disease, suggested that local immune mechanisms were important in resistance. It is proposed that an effective vaccination schedule to protect mice against M. pulmonis-induced respiratory disease may be one that stimulates both systemic and local immune defenses. This suggestion is supported by the observation that systemic followed by local administration of inactivated M. pulmonis was more effective in inducing resistance in mice to intranasal challenge with live organisms than was systemic administration alone. In addition, mice inoculated solely by the intranasal route with inactivated mycoplasmas were resistant to M. pulmonis-induced respiratory disease. These studies indicate the importance of local defense mechanisms in the induction of resistance to M. pulmonis-induced respiratory disease in mice.


Mycoplasma-induced hydrocephalus in rats and hamsters. Mycoplasma pulmonis, a pathogen of the respiratory tract in rats, was inoculated intracerebrally into neonate rats and hamsters to determine if it would induce lesions in the ependyma. Hydrocephalus was induced in 116 of 120 rats and in 23 of 28 hamsters. The severity of hydrocephalus was greater in the rats than in the hamsters. Hydrocephalus induction occurred only subsequent to inoculation of viable M. pulmonis. At 2 weeks of age, rats became refractory to induction of hydrocephalus. Light microscopy indicated that the hydrocephalus was communicating without an inflammatory response in the ventricles and meninges. Preliminary electron microscopy revealed that amorphous material covered portions of the ependymal surface and that cilia were sometimes matted together. It was suggested that the hydrocephalus was due to ciliary dysfunction or to an imbalance of cerebrospinal fluid secretion and absorption. This M. pulmonis-induced hydrocephalus may be a useful model for elucidating the pathogenesis of certain types of congenital hydrocephalus in humans.


Differences among medical professionals in their attitude toward drugs. This study was designed to explore the characteristics of medical personnel who might be related to illicit opiate use. Physicians, veterinarians, and dentists, all professionals having relatively high access to opiates, were compared on a number of attitudinal variable relating to drugs. Group differences were observed in regard to the perceived benefit and potential danger of specific drugs. The authors advocate a focus on the role demands of the professional rather than an analysis of the personality characteristics of individuals within the profession.


Sulfur metabolism of a mutant of Cephalosporium acremonium with enhanced potential to utilize sulfate for cephalosporin C production. Characteristics of a mutant of Cephalosporium acremonium with enhanced potential to utilize sulfate for cephalosporin C production were investigated with sulfur-starved cells. DL-Norleucine showed an inhibitory effect on cephalosporin C and penicillin N production by the mutant in the presence of a sulfur source such as sulfate, sulfite, thiosulfate, and L-cystine, but it exhibited no effect when it was added after a certain period of incubation. On the contrary, antibiotic production by the parent was stimulated by norleucine regardless of the addition time. An increase in the intracellular cysteine pool was found when the cells were incubated with L-methionine or norleucine and sulfate. Enzymatic studies revealed that methionine and norleucine stimulated the cysteine desulfhydrase formation, and this effect was significant in the mutant. Finally the mutant was found to have an enhanced L-serine sulfhydrylase activity. The increase in this enzyme activity in the mutant seems responsible for the increase in the sulfate-utilizing ability and the methionine sensitivity by maintaining a high level of the cysteine pool. Accordingly, the effect of methionine and norleucine is assumed to be exerted through cysteine.


Adaptations to endurance training at three intensities of exercise. This study was undertaken to investigate the influence of exercise intensity (running speed) on a number of alterations that are known to occur with exercise training. Rats were trained on three treadmill running schedules: 20 m/min, 27 m/min, and 35 m/min for 1 h/day. After 6 wk, lean body mass and body fat content were decreased to the same extent in all three trained groups. Thus, exercise appears to lower body fat by some mechanism that is not related to the amount of energy expended during exercise. Heart and adrenal gland weight-to-lean body mass ratios were increased by training. Heart weight-to-lean body mass ratio increased with increasing intensity of exercise but the adrenal weight-to-lean body mass ratio was independent of exercise intensity. Training increased muscle succinate dehydrogenase activity to the same extent in all three trained groups which suggests that the adaptation in respiratory capacity is not altered greatly by the intensity of training.


Glucocorticoid induction of growth hormone synthesis in a strain of rat pituitary cells. Conditions were determined for measuring growth hormone synthesis by a clonal strain of rat pituitary cells grown in suspension culture. Incubation of the cells with [3H]leucine in either continuous labeling or pulse-chase experiments showed that secretion of newly synthesized growth hormone commences only after a lag of about 15 min. The pulse-chase experiments also demonstrated that there is no detectable degradation by the cells of growth hormone. Thus growth hormone synthesis could be measured, in the absence of complications arising either from secretion or degradation of growth hormone, by incubating the cells with [3H]leucine for 10 min. Exposure of cells grown under the usual culture conditions to dexamethasone (a synthetic glucocorticoid) led to an average stimulation of specific growth hormone synthesis (growth hormone synthesis/total cytoplasmic protein synthesis) of only 2.6-fold. However, two other growth conditions were found in which dexamethasone routinely yielded a 5- to 15-fold stimulation of specific growth hormone synthesis. One of these conditions, involving substitution of 10% fetal calf serum for the normal serum supplement, was employed in subsequent experiments. A stimulation of specific growth hormone synthesis could be observed at 10(-9) M dexamethasone, and the maximum stimulation was observed at dexamethasone concentrations of about 10(-8) to 10(-7) M. There was a lag of about 6 h before a stimulation by dexamethasone of specific growth hormone synthesis was detected. Thereafter, the stimulation increased in a nearly linear fashion until maximum stimulation was reached at about 48 h.


Precursors of ribosomal RNA in the cellular slime mold Dictyostelium discoideum. Isolation and characterization. The pathway of ribosomal RNA biogenesis in Dictyostelium discoideum has been defined through identification, isolation, and characterization of the rapidly labeled nuclear RNAs which are intermediates in the process. Comparison of the methylation patterns, base compositions, two-dimensional oligonucleotide maps, and hybridization properties of these intermediate RNAs with those of mature rRNAs has established clearly the precursor-product sequence relationships supporting the following scheme for rRNA production and processing: (formula: see text) The relationship of the 37 S RNA of Dictyostelium to primary rRNA transcripts of prokaryotes and other eukaryotes is discussed.


Inhibition of protein synthesis by Cl-.

Inhibition of protein synthesis by Cl-. Optimum K+ concentration for protein synthesis in four eukaryotic cell-free systems is obtained with 70 to 80 mM added KCl or with 110 to 150 mM added K(OAc). The different K+ optima are due to inhibition of protein synthesis by Cl- at concentrations higher than those present in the cytoplasm of eukaryotic cells. Initiation of protein synthesis is severely inhibited with 150 mM added KCl. This inhibition results from an impairment of mRNA binding to ribosomes. The binding of initiator Met-tRNAt, however, is only slightly inhibited by 150 mM KCl.


Isolation and characterization of two enzymatic activities from chick embryos which degrade double-stranded RNA. Enzymatic activities capable of degrading double-stranded RNA have been solubilized from whole 9-day-old chick embryos and separated by ion exchange chromatography on DEAE-cellulose into two classes, designated nucleases DI and DII. Nuclease DI exhibits an absolute requirement for Mn2+ in the range of 5 to 10 mM. Monovalent cations, including K+, Na+, and NH4+, are inhibitory. The molecular weight of DI is 60,000 to 62,500 as estimated from sedimentation in sucrose density gradients. Following gradient fractionation, nuclease DI possesses the ability to degrade several substrates exhibiting a 250-fold preference for poly(rC) as compared to poly(rC)-poly(rG). The activity responsible for degrading double-stranded RNA functions as an endonuclease generating oligonucleotides with 5'-phosphate termini. Nuclease DII requires both monovalent and divalent cations. Optimal degradation of poly[r(A-U)] is seen at 75 to 100 mM salt and 0.5 to 1.0 mM MgCl2 or MnCl2. The molecular weight estimated from sucrose gradient sedimentation is in the range of 38,000 to 40,000. Nuclease DII acts endonucleolytically producing oligonucleotides terminating in 5'-phosphates. During the isolation and characterization of nucleases DI and DII, a third activity was detected which degrades single-stranded RNA substrates but which, in the presence of either DII or RNase H, significantly enhances the degradation of poly[r(A-U)] or poly(rA)-poly(dT) substrates.


Cation specificity of propranolol-induced changes in RBC membrane permeability: comparative effects in human, dog and cat erythrocytes. Propranolol, in the presence of calcium, causes marked K efflux from human red blood cells (high K, low Na). The studies reported here indicate this effect of propranolol is specific for K and does not represent a nonspecific permeability increase for intracellular cations to leave the cell. Amphotericin-treated human RBC's (high Na, low K) and dog RBC's (high Na, low K) both gain K and increase in size when incubated in a K-medium containing propranolol and calcium. No effect was noted when cat RBC's (high Na, low K) were similarly treated. Propranolol, independent of added calcium, also inhibited the normally increased Na efflux observed when dog RBC's are suspended in K-medium. These species differences in response to propranolol thus may serve as a focus for elucidating the mechanism by which this drug alters normal membrane physiology. The unique drug effect on Na permeability of canine erythrocytes also may be a useful probe for the study of dog RBC volume regulation.


Cells regulate their proliferation through alterations in transition probability. The proliferation of 3T3, 3T6 and SV3T3 cells was examined by time lapse cinephotography under a number of different growth conditions. It was found that the frequency distributions of intermitotic times of cells with widely different proliferation rates are qualitatively and quantitatively explained by the transition probability model of the cell cycle (Smith and Martin, '73). The behaviour of quiescent cells was characterized by very low values of the transition probability. No "out of cycle" or GO compartment of cells was detectable. From a consideration of these results and those in the literature it appears that the rate of cell proliferation is determined by the value of the "transition probability" (P), and that it is the biochemical manifestation of this parameter that regulates cell growth in vitro and in vivo.


Combined valvular aortic stenosis, hypertrophic subaortic stenosis and coronary artery disease: successful surgical correction. A 51 year old woman with angina pectoris due to combined valvular aortic stenosis, hypertrophic subaortic stenosis and coronary artery disease is described. The diagnosis was first suspected following echocardiography. Discussed is the importance of excluding associated coronary artery disease and hypertrophic subaortic stenosis in patients with valvular aortic stenosis. A pre- and post-PVC aortic pressure response is described pathognomonic of coexistent valvular and hypertrophic subaortic stenosis. The patient underwent successful surgical correction of all three lesions.


Proline oxidase in cultured mammalian cells. We sought a cultured cell line with Proline Oxidase activity to study the regulation and physiologic role of the enzyme in mammalian tissues. Among the cell lines tested, only LLC-RK1 cells, derived from rabbit kidney, had significant Proline Oxidase activity; the Km for proline of the enzyme from these cells was similar to that for the liver enzyme. LLC cells, Proline Oxidase positive, were able to convert proline to CO2. In contrast, CHL cells, Proline Oxidase negative, did not have this capability. The presence of Proline Oxidase in LLC cells and the absence of the enzyme in fibroblasts suggest that Proline Oxidase may serve as a marker enzyme for distinguishing parenchymal kidney cells from fibroblasts in culture. Cells transformed by SV40 virus and cells transformed by methylcholanthrene had activities higher that the parent cell line, but this effect of transformation could not be generalized to all transformed cells. Finally, L-hydroxy proline at 100-fold greater concentration than substrate L-proline failed to decrease proline oxidation. This finding suggests distinct degradative enzymes for these two amino acids.


Embryonal carcinoma cells (and their somatic cell hybrids) are resistant to infection by the murine parvovirus MVM, which does infect other teratocarcinoma-derived cell lines. Minute virus of mice (MVM), a non-defective parvovirus, has been shown to infect cultures of non-pluripotent differentiated teratocarcinoma-derived cells, but pluripotent (and "nullipotent") embryonal carcinoma cells derived from the same teratocarcinoma resist MVN infection. Somatic cell hybrids between an embryonal carcinoma line and Friend erythroblastic leukemia cells are also resistant to MVM, even though Friend cells are susceptible. Among three blastocyst-derived lines tested, only one, a parietal yolk sac cell line, resists MVM infection. These results suggest that teratocarcinoma cultures may provide useful systems in which to study the cellular factors which mediate susceptibility to this teratogenic and oncolytic virus.