Correlates of illness susceptibility.

Previous research has indicated that congitive-emotional factors, psychosocial stress, and systemic activity play a role in the contraction and course of numerous diseases. The present study investigated the relative contributions of these variables. Fifty-five male undergraduates were given questionnaires assessing general emotionality, and psychosocial stress and illness history over a four-year period. Autonomic indices of pulse rate, respiration, peripheral circulation, and skin resistance were also obtained under conditions of rest and stress (threat of electric shock). Using number of past illnesses as the dependent variable, a stepwise multiple regression analysis was performed. Only amount of psychosocial stress and, related to it, number of different kinds of psychosocial stress yielded significant partial correlations. Results are discussed in relation to other research, with emphasis on the conceptual and methodological difficulties of assessing psychophysiological mediators of morbidity.


Variability in grading diabetic retinopathy from stereo fundus photographs: comparison of physician and lay readers.

Two physicians and two lay readers were trained according to a detailed protocol in the grading of 17 lesions found in diabetic retinopathy by evaluation of stereo fundus photographs according to a modified Airlie House classification. Intraobserver and interobserver variability of these readers was assessed by two methods: weighted kappa, and frequency of agreement within one grade. In general, physician readers were found to be less variable on replicate readings than were lay leaders, and had slightly better agreement with each other than with the lay readers. The physiological significance of the direction and magnitude of the difference between physician and lay reader variability for individual lesions was often uncertain. Assessment of contribution to disagreement by individual readers was possible and permits future training directed at reducing disagreement to acceptable values.


Primary vitrectomy as a preventive surgical procedure in the treatment of severely injured eyes.

The results of treating 72 severely injured eyes by primary vitrectomy combined with anterior and posterior segment reconstruction are presented. This approach aims at improving the visual prognosis by allowing fundus examination and immediate retinal surgery where indicated, and by preventing the more severe complications associated with vitreous and anterior segment disorganisation. The prospects for improved visual results and the problems encountered, particularly secondary haemorrhage, are discussed.


Medulloepithelioma (diktyoma) presenting as a perforated, infected eye.

A case of embryonal medulloepithelioma (diktyoma) presenting with perforated infected eye in a 13-year-old Black African girl is described. The tumour mass occupied most of the deformed eye, and invasion of the sclera anteriorly was seen. There was no evidence of orbital or distant tumour involvement. It is suggested that with increasing age these tumours are more likely to show frankly malignant features.


Operating microscope eyepiece heaters.

Precipitation of water vapour from expired air on to exposed eyepiece lenses of operating microscopes can seriously interfere with the surgeon's view. By  warming these optical surfaces to temperatures well above the dew point of expired air this problem is eliminated. A pair of small heaters were designed to clamp over the eyepiece tubes of a standard operating microscope and their effectivity assessed.


A protein cofactor that stimulates the activity of DNA-dependent RNA polymerase I on double-stranded DNA.

Partially purified rat liver RNA polymerase I chromatographed on ribosomal RNA-Sepharose loses most (96%) of its activity assayed on native calf-thymus DNA templates, but loses little (8%) of its activity assayed on poly(deoxycytidylic acid) template. Polymerase I is not stimulated by polymerase II protein factor, or by bovine serum albumin. However, it is stimulated by histones, polylysine, and spermine. Addition of a protein fraction eluted by high ionic strength from the rRNA-Sepharose also restores activity on native calf-thymus DNA. Further purification yields a fraction containing two proteins of 11 000 and 12 000 molecular weight. Both proteins are distinct from histones by electrophoresis in sodium dodecyl sulfate and in acid urea. Both proteins are basic, insensitive to heat, bind to DNA, and stimulate polymerase I activity. The degree of stimulation of polymerase I is dependent upon both the enzyme/DNA and the factor/DNA ratio. The protein factors also stimulate polymerase II activity about half as effectively as polymerase I.


Amino acid sequence studies on the alpha chain of human fibrinogen. Isolation and characterization of two linked alpha-chained cyanogen bromide fragments from fully cross-linked fibrin.

Fully cross-linked human fibrin was digested with cyanogen bromide and the resulting fragments were characterized and compared with the fragments produced upon cyanogen bromide treatment of fibrinogen alpha chains. The largest molecular-weight fraction isolated by gel filtration on Sephadex G-150 was reduced and alkylated, and upon rechromatography on Sephadex G-150 it eluted at the same place as the original material. This large molecular weight fraction was subjected to amino acid analysis and the amino-terminal sequences of its constituent chains were determined by both dimethylaminonaphthyl sulfonation (Dns) and thioacetylation procedures. The identified sequences corresponded to two cyanogen bromide fragments previously found in alpha chains isolated from fibrinogen, one of which has a molecular weight of about 30 000 and the other 6000. The latter is thought to be the carboxy-terminal penultimate cyanogen bromide fragment of the alpha chain.


The light dependent uptake of N-methylphenazinium cations by the thylakoids of isolated chloroplasts.

The absorption of N-methylphenazinium methylsulfate (MP+ methylsulfate) in suspensions of envelope-free chloroplasts is reversibly lowered in the light. When the electron transport system of the chloroplasts is inhibited by 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU), the photobleaching reflects an uptake of MP+ into the thylakoids. Its magnitude is a function of the composition and of the pH of the suspension medium and, most importantly, is controlled by the availability of permeant anions which apparently accompany MP+ into the thylakoid as counterions. Consequently, the rate of the bleaching is strongly dependent on the permeability of the thylakoid to the available anion. At pH 7.5, the thylakoids of DCMU poisoned pokeweed chloroplasts are able to hold at least 6 MP+/chlorophyll. It is proposed that, in the presence of MP+, the light reaction of Photosystem I in DCMU-inhibited chloroplasts causes a conformational change of the membranes which exposes nucleophilic sites inside the thylakoids. These sites appear to have a high affinity for MP+, but may bind protons or other cations under certain experimental conditions. The uptake of MP+ has a hypochromic effect on its absorption band in the near ultraviolet due to the resulting heterogeneous distribution of the dye cation between medium and chloroplast grana.


Oxidation-reduction coupled phosphorylation in the dark with isolated spinach chloroplasts.

1. Spinach chloroplasts, pre-incubated with ferricyanide, acquire the ability to make ATP in the dark provided they are supplied with a reductant and a lipophilic mediator that can penetrate the membrane. The mediator must be of the type that, upon oxidation, releases protons into the surrounding medium such as 2,3,5,6-tetramethyl-p-phenylenediamine (DAD). 2. Dark phosphorylation is not affected by the electron transport inhibitor, 3(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU) or 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB), but is inhibited by uncouplers of photophosphorylation (e.g. NH4Cl and carbonylcyanide-m-chlorophenylhydrazone (CCCP)) and high concentrations of the energy transfer inhibitor, Dio-9. 3. Because only catalytic amounts of the mediator DAD are required to saturate dark phosphorylation, it is concluded that DAD shuttles reducing equivalents across the membrane from the reductant, ascorbate, on the outside to ferricyanide, the oxidant, trapped on the inside. 4. The results are interpreted within the framework of the chemiosmotic hypothesis for the coupling of electron transport to phosphorylation.


Pyruvate transport in tumour-cell mitochondria.

Tumour-cell mitochondria contain a pyruvate-transporting system exhibiting the same general properties as those described in rat liver mitochondria. The Km for net pyruvate uptake in tumour-cell mitochondria is practically similar to that measured in rat liver mitochondria but the V is lower. This difference is also shown by swelling experiments. The possible implication of these observations in the context of lactate accumulation in tumour-cell is discussed.


Isolation of plasma membranes from murine ependymoblastoma and subcellular distribution of amphotericin B in this tumor.

A method for the isolation of plasma membranes from an experimental murine ependymoblastoma is described. In this procedure, 5'-nucleotidase was used as the plasma membrane marker, since cytochemical methods demonstrated that the enzyme was present on this subcellular structure only. The final plasma membrane preparation showed a 15-fold enrichment in 5'-nucleotidase activity and a 17-fold enrichment in the activity of phosphodiesterase I, another plasma membrane marker. The specific activity of beta-glucuronidase (lysosomal enzyme) was twice that of the whole homogenate, the specific activity of arylesterase (microsomal enzyme) was similar to that of the whole homogenate and succinate dehydrogenase (mitochondrial marker) was not detected. Electron microscopy of this fraction showed vesicles on which 5'-nucleotidase activity could be demonstrated. The subcellular distribution of [3H]amphotericin B per mg of protein was similar in the plasma membrane preparation and in the whole homogenate. It is concluded that, in ependymoblastoma, amphotericin B shows no selective affinity for the plasma membrane.


Control of fatty acid composition of Acholeplasma laidlawii membranes.

The temperature-dependent pattern of incorporation of palmitate and oleate from the growth medium into Acholeplasma laidlawii membrane lipids correlates with the physical state of the membrane defined by calorimetry. Both the pattern and the state can be changed at will by changing the fatty acid composition of the membrane lipids. The ratio of palmitate to oleate incorporated is independent of temperature when the membrane bilayer is below its transition and fully ordered, but becomes temperature dependent upon the onset of the transition and continues to be temperature dependent when the membrane is above its transition  and fully fluid. This behavior is mimicked by the physical binding of palmitate and oleate to bilayers of extracted membrane lipids and to bilayers of lecithin. Selective binding by membranes may provide a means for controlling lipid fatty acid composition without invoking an enzymatic mechanism.


Heterogeneity of the beta-amino-preferring transport system in rat kidney cortex. Differential influence of glutathione oxidation.

Taurine, a naturally found beta-amino acid, is inert in rat renal cortex slices. Its active accumulation by slices is abolished by anaerobiosis, a strongly acidic media or the removal of Na+. Concentration-dependent uptake studies reveal more than one taurine carrier: the apparent Km value for uptake below 1.1 mM is 0.4 mM and the apparent Km value above 1.1 mM is 14.5 mM. Of all amino acids tested only beta-alanine, another beta-compound, inhibited uptake. The oxidizing agent diamide was used to lower the concentration of GSH in rat cortex slices. The ability to accumulate taurine by the low Km system was decreased in diamide-treated slices, but not by the high Km system. Diamide was found to greatly augment efflux of taurine taken up from lower concentrations but not from higher concentrations. GSH in the media prevented this diamide-induced inhibition of uptake and enhanced efflux at lower taurine concentrations. A possible mechanism of diamide inhibition of uptake is that intracellular GSH depletion leads to greatly enhanced efflux of taurine, thus preventing uptake.


The synthesis of polyadenylated RNA and other RNA species in synchronised CHK cells.

Chinese hamster kidney cells have been synchronised by the double thymidine block technique. The rate of incorporation of [5-3H]uridine into the polyadenylated RNA fraction has been analysed throughout two complete cell cycles and compared with the rate of incorporation into other RNA species and the UTP pool. In contrast with other reports, we have found that synthesis of 18 S rRNA continues steadily throughout the cell cycle, as does synthesis of 5 S RNA and tRNA. In the case of the polyadenylated RNA, however, our data indicate a major peak of synthesis during S phase and a smaller peak coinciding with G1.


Synthesis of polynucleotides which contain 3,N4-ethanocytidine, a nucleoside modification resulting from the action of bis(chloroethyl)-nitrosourea.

BCNU,N,N1-bis(2-chloroethyl)-N-nitrosourea is known to produce 3-hydroxyethylcytidine and 3,N4-ethanocytidine when it reacts with polycytidylic acid. The nucleoside, 3,N4-ethanocytidine, presumably results from cyclization of 3-chloroethylcytidine formed initially by transfer of chloroethyl carboniumions from BCNU to cytidine. In order to study the significance of this unusual derivative, we have synthesized 3,N4-ethanocytidine and converted it to the corresponding 5'-mono- and diphosphates. 3,N4-Ethanocytidine diphosphate has been successfully converted to a high molecular weight polymer.


The structural organization of nuclear pre-mRNA. II. Very long double-stranded structures in nuclear pre-mRNA.

High molecular weight nuclear pre-messenger RNA (pre-mRNA or hnRNA) isolated from Ehrlich ascites carcinoma cells contains besides moderately long (100--200 base pairs) snap-back double-stranded structures, also longer double-stranded structure containing at least 300--800 base pairs. Their double-stranded nature was proved by Cs2SO4 gradient centrifugation. Very long double-stranded sequences are not able to snap-back after RNA melting. While the moderately long double-stranded RNA (dsRNA) is renatured at C0t1/2 approximately equal to 5-10(-4), the very long dsRNA shows a higher complexity (C0t1/2 approximately equal to 2-10(-2). They also hybridize to less reiterated class of DNA than moderately long dsRNA. Two classes of dsRNA are represented by different sequences as followed from cross-renaturation experiments. Very long dsRNA forms stable hybrids with 20% of total poly(A)+mRNA of cytoplasm. The properties of different classes of ds structures present in nuclear pre-mRNA are compared and their possible nature is discussed. The presence of very long dsRNA may reflect either the symmetric transcription of structural genes, or the transcription from those DNA sequences which are complementary to each other but located in different parts of the genome.


Structural repeating units in chromatin. III. A comparison of chromatin subunits from vertebrate, cilliate and angiosperm species.

A comparison was made of the chromatin subunit ("nu"body) structure present in nuclei from chicken erythrocytes, Tetrahymena cells, and Pisum sativum (pea) buds. All three types of chromatin yielded spherical subunits upon nuclease digestion which were indistinguishable in the electron microscope, and contained approximately the same amount of DNA. There were, however, consistent and significant differences in the digestion patterns of chromatin from the three organisms.


Optical and hydrodynamic studies of the structure of bacteriophage f2. II. Fluorescence of the capsid.

Fluorescence properties of the icosahedral RNA virus bacteriophage f2 and its empty capsid are reported. Emission is dominated by tryptophan with a maximum wavelength of 320 nm for f2 and its empty capsid. In addition to this short wavelength maximum, perturbation and denaturation studies indicate the inaccessibility of the tryptophan residues. However a high degree of thermal quenching and a red shift in fluorescence emission on heating suggest a noncooperative structural transition, not a denaturation, which allows buried tryptophans to become exposed to solvent. Therefore the tryptophan residues may be located between subunits. Fluorescence from tyrosine is detected near 315 nm for both f2 and its empty capsid, and may indicate an unusual tyrosine environment. Sensitization of tryptophan fluorescence by tyrosine absorption and low values of polarization indicate tyrosine leads to tryptophan and tryptophan leads to tryptophan energy transfer. The presence of RNA in f2 decreases the efficiency of these transfer processes, but does not significantly affect the other reported fluorescence properties.


DNA replication intermediates in whole HeLa cells and isolated nuclei.

Replicative intermediates have been studied in intact HeLa cells and in nuclei isolated from such cells. In whole cells the smallest DNA (primary DNA pieces) observed after pulse labelling with [3H]thymidine were 90-160 nucleotides long, and the size of the molecules in this class of DNA did not increase with increasing pulse length. Some increase in size was, however, observed when cells were pulse labelled at 25 degrees C instead of 37 degrees C. Chase experiments using nuclei from pulse-labelled cells suggested that the primary DNA pieces could be chased rapidly into DNA of high molecular weight (30-70 S, corresponding to a molecular weight of 0.7 - 10(7)-6.4-10(7)). Longer chases showed that the label eventually accumulated in DNA with s values greater than 150 S. In isolated nuclei the primary DNA pieces after a 1 min pulse at 37 degrees C were approximately 200 nucleotides long. Primary pieces of this size were also rapidly chased into the 30-70 S region. However, during longer pulses in vitro a fraction of the primary DNA pieces grew beyond their normal size to reach a size of up to 2000-3000 nucleotides before being attached to the 30-70 S molecules.


Protein synthesis inhibitors and export of ribosomal subunits.

Puromycin and cycloheximide inhibit nuclear export of ribosomal RNA in Chironomus salivary gland cells like in mammalian cells. The drugs do not prevent other types of RNA like heterodisperse messengerlike RNA, 75-S RNA of Balbiani ring origin and 4-S RNA from appearing in the cytoplasm. Newly exported ribosomal subunits have previously been found to enter polysomes close to the nuclear envelope in these cells. The basis for the specific export-blocking action of the drugs may be that immediate engagement in polysomes is a prerequisite for export of ribosomal subunits.


Characterization of ribonucleoprotein particles from the protozoa Astasia longa.

Ribonucleoprotein particles released from nucleoli of Astasia longa by treatment with heparin were characterized biochemically. When centrifuged in a sucrose gradient containing an appropriate buffer (Tris/KCl/Mg2+), four populations of particles were obtained, sedimenting at 90 S, 75 S, 60 C, and 44 S, respectively. The first type of particles contained the high molecular weight (3.5-10(6) ribosomal RNA precursor. The RNAs present as the major components in the 75-S and 44-S particles had molecular weights of 1.35-10(6) and 0.85-10(6), respectively, whereas the 60-S particles contained a mixture of 0.85-10(6) and 1.35-10(6) RNA. After a brief labeling, the radioactivity was found in the RNA constituent of the 90-S particles; following a 90 min chase, the label disappeared from this latter fraction and accumulated in the 75-S, 60-S and 44-S particles. This indicates a precursor-product relationship between the RNA of the 90-S particles and that of the three other ribonucleoprotein particles, consistent with the conversion:: 3.5-10(6) RNA LEADS TO 1.35-10(6) RNA+0.85-10(6) RNA.


Cyanide sensitivity and induction of the microsomal oleoyl-CoA desaturase of potato tuber.

1. The properties of oleoyl-CoA desaturase, induced in microsomal fractions by the 'ageing' treatment of potato tuber slices (aeration of slices for 3-18 h), were investigated to study the effect of cyanide on desaturation and cycloheximide on the induction of the desaturase. 2. The electrons needed for the desaturation can be supplied either by NADH or NADPH, but ascorbate can also drive the reaction; experiments with CO suggested that cytochrome P-450 was not involved in the desaturation. 3. A strong inhibition of the desaturation by potassium cyanide was observed with each of the electron donors; total inhibition was noticed with 1 mM KCN; low concentrations (0.1 mM) caused 50% inhibition of the desaturation. 5. The variation of the oleoyl-CoA desaturase activity during the ageing process and the drop in this activity in aged slices treated by cycloheximide indicate that the enzyme undergoes an active turnover.


Hydrolysis and uptake of an aliphatic fatty ester by whole isolated fat cells.

During 9-min incubations at 37 degrees C, whole isolated fat cells are able to hydrolyze a water-insoluble ester, ethyl [3H]oleate, added as an emulsion to the extracellular medium. The monoester lipase exerts its activity as a membrane-bound enzyme and is not releasable by heparin. Variation of the reaction rate with substrate concentration suggests a diffusion-limited process, consonant with the fact that enzyme and substrate are associated with particles of enormous sizes (the fat cell and the lipid droplet, respectively). Variation of lipase activity with increasing temperature in the incubation medium shows a break at 46 degrees C +/-1 degrees C, most probably related to a phase transition in the membrane structure. During incubation, 30-60% of the amount of [3H]oleic chains formed by hydrolysis are incorporated into the cell, mainly as triacylglycerols. Controls of cell viability indicate that under the experimental conditions the framework of the membrane and the internal organization of the cell appear to be maintained. Such an experimental model might duplicate physiological conditions since aliphatic fatty esters are thought to be hydrolyzed at the cell surface during uptake.


Some physical properties of free and esterified cholesterol mixtures: studies on relative stability of cholesterol ester ratio in blood plasma.

Some physical properties of the mixtures composed of esterified and free cholesterol at various ratios were measured. Addition of a small proportion of free cholesterol, lowered slightly the melting point of the esterified cholesterol fraction from human plasma and it was kept nearly constant at this level by the addition of 30-40% of free cholesterol. Further addition of free cholesterol resulted in an abrupt rise in the melting point. The ranges of the stable plateau were clearly wider in esterified cholesterol with more polyunsaturated acids. The extent of inhibition of monolayer formation of free cholesterol with cholesterol palmitate was found to be greatest at a mixture ratio of 60-70%. In the case where cholesterol palmitate was added to an equimolar mixture of dipalmitoyl glycerophosphocholine and free cholesterol, a trimolecular mixed monolayer was formed above the mixing ratio, 7.5:2.5, of esterified and free cholesterol. The present studies clearly showed that there were distinct changes in some physical properties examined at the molar ratio of esterified cholesterol:free cholesterol of about 7:3.


Phospholipid degradation in isolated rat hepatocytes. Metabolism of intracellularly formed dilinoleoyl-dipalmitoyl- and dimyristoylglycerophosphocholine.

The aim of this work is to describe the role of different phospholipases in hepatic phospholipid catabolism. Therefore isolated rat hepatocytes enriched in labeled dilinoleoyl-, dipalmitoyl- or dimyristoylglycerophosphocholine were prepared by pulse incubation with [3H]glycerol and 14C-labeled fatty acid. The labeled cells were chased up to 4 h in a tracer-free medium and the degradation of different phosphatidylcholines studied. After a 2-h chase about 40% of dilinoleoyl-, 70% of dipalmitoyl- and 30% of dimyristoylglycerophosphocholine were degraded. From the positional distribution of 14C-labeled fatty acid and the change in the doubly labeled molecular species of phospholipids, it was concluded that tb degradation of dilinoleoylglycerophosphocholine and that of phosphatidylethanolamine could be accounted for by the action of phospholipase A1, while the degradation of dipalmitoylglycerophosphocholine proceeded through the action of phospholipase A2. Dimyristoylglycerophosphocholine was probably cleaved by the combined action of both phospholipases A1 and A2. Up to 10 mM tetracain, added to the chase medium, effectively blocked the action of both phospholipase activities. A considerable part of 2-linoleoyl- and 1-palmitoylglycerophosphocholine liberated during the chase was reutilized for phosphatidylcholine synthesis without further degradation.


The use of iodinated tracers for a sensitive radioimmunoassay of 13,14-dihydro-15-ketoprostaglandin Falpha.

Radioimmunoassay of 13,14-dihydro-15-ketoprostaglandin Falpha is reported using various 125I-labelled derivatives. The apparent association constants of the antiserum for iodinated tracers are higher than with the homologous hapten. In spite of this, the high specific activities of iodinated tracers (2000 Ci/mmol) allow a 3-fold increase in the sensitivity of the assay when compared with the tritiated derivative. Human plasma levels of 13,14-dihydro-15-ketoprostaglandin Falpha reported (25+/-6 pg/ml) are lower than those previously found by radioimmunoassay, and no sexual difference was found.


Depletion of docosahexaenoic acid in retinal lipids of rats fed a linolenic acid-deficient, linoleic acid-containing diet.

Rats were raised for 2 generations on a diet in which 1.25% methyl linoleate was the only source of fat. Control rats were given 1.0% methyl linoleate plus 0.25% methyl linolenate. Lipids were extracted from retinas and their fatty acids were analyzed by gas-liquid chromatography. Docosahexaenoic acid accounted for 33.8% of total fatty acids in control retinas, for 13% of fatty acids in first-generation deficient retinas, and for 2.7% of fatty acids in second-generation deficient retinas.


The 6-ketoprostaglandin F1alpha pathway in the lamb ductus arteriousus.

Homogenates of the lamb ductus arteriosus at term have the capacity to convert exogenous arachidonic acid into prostaglandins E2, F2alpha and 6-ketoprostaglandin F1alpha. No evidence was obtained for the formation of prostaglandin D2 and thromboxane B2. All products were quantitated by mass spectrometry. 6-Ketoprostaglandin F1alpha was the major compound, formed in amounts in excess of 10 fold over prostalgandins E2 and F2alpha.


Effects of a juvenile hormone mimic on male and female gametogenesis of the mud-crab Rhithropanopeus harrisii (Gould) (Brachyura: Xanthidae).

1. Effects of ingestion and topical application of 1.30 ppm methoprene, an insect juvenile hormone (JH) mimic, include gametogenesis disorders in both male and female mud-crab Rhithropanopeus harrisii. 2. Progressive inhibition of vitellogenesis and stimulation of spermatogenesis take place after a short exposure time (12-15 days), whereas a longer period (between 30 to 45 days) promotes inhibition of both spermatogenesis and vitellogenesis. Such modifications demonstrate the chemosterilizing action of methoprene on crustaceans. 3. Stoppage of vitellogenesis is characterized by a blockage of oocytes at terminal previtellogenesis and proliferation of the follicle cells involved in vitellogenic oocyte lysis. Spermatogenic degeneration begins with the amalgam of spermatocyte clusters in meiotic prophase and pycnosis of gonia. 4. Analogies between these results and those obtained from experiments involving androgenic gland implantations or the consequences of their hyperfunctioning are discussed.


[Alteration of the lipid composition of rat liver microsomes on reconstitution of the cytochrom P-450 system. Inactivation of the enzyme by lysolecithin].

The lipid composition of rat liver microsomes, their "ghosts" and the reconstituted membrane hydroxylation system was investigated. The phospholipid content and composition of the reconstituted membranes were found to depend on the reconstitution method. The reconstituted membranes contained besides phospholipids also cholesterol and gangliosides. The cholesterol/phospholipid ratio of the reconstituted membranes was the same as that of the initial microsomes. Lysolecithin was shown to enhance the conversion of the active form of cytochrom P-450 to the inactive cytochrome P-420.


[Some biochemical properties of Acholeplasma laidlawii mutants defective in glucose carrier].

Some membrane properties of glucose transport system of Acholeplasma laidlawii mutants uncapable of uptaking glucose as well as those of its non-metabolizing analogue, 3-0-methylglucose are studied. In contrast to the wild strain the mutant PTL-S cells fail to uptake carbohydrates with the saturation. There is no competition between carbohydrates during transport in this mutant no sugar exit is observed, and the sensitivity of transport to thiol reagents and pronase B is considerably affected. All other investigated membrane functions were intact. The data given indicate the presence of a specific defect in glucose transport system.


[Effect of the light on the biosynthesis of inorganic polyphosphates and some phosphoorganic compounds in Chlorella pyrenoidosa Chick].

The illumination of Chlorella cells is found to affect the biosynthesis of different inorganic polyphosphates (IPP) and phosphoorganic compounds. The synthesis of IPP fractions, extracted with TCA at 0 degrees C and perchloric acid at 100 degrees C, is carried out with the cooperation of photochemical reactions, while the formation of other IPP fractions is light-independent. Ohosphorus incorporation into nucleic acids and phosphoproteins is due to the effect of the light, and phosphorylation of carbohydrates and phospholipids is a dark process.


[DNA from chromatin-nuclear membrane complex: reassociation kinetics at different stages of the cell cycle].

Base composition and reassociation kinetics of DNA from chromatin-nuclear membrane complex of rat liver cells at different stages of the cell cycle. The complex isolated in low ionic strength solutions contains about 9% of total nuclear DNA, and its density in sucrose solution is 1.27 g/cm2. DNA, isolated from the complex, is homogenous in its molecular weight (approximately 2-10(6) daltons) and is similar in its base composition to total nuclear DNA. However, DNAs from complexes, isolated at interphase and different S-phases of the cell cycle, differ from total nuclear DNA in reassociation kinetics: DNAs from complexes are enriched by approximately 10% with unique nucleotide sequences. It is concluded from the similarity of reassociation kinetics, that molecular population of nuclear membrane-bound DNA does not change considerably throughout the cell cycle.


[Immobilization of ferredoxin].

The method of pea ferredoxin (Fd) immobilization has been worked out. Under binding Fd with sepharose 4B activated by cyanogen bromide, a destruction took place in the Fd active center and apoprotein was bound with the matrix. The native immobilized Fd has been obtained when using P-300 biogel as a matrix. The gel was activated by glutaraldehyde and protein was linked with gel through a hexamethylenediamine spacer.


[Metabolism of mRNAs of membrane-bound and free-polyribosomes from rat liver cells during translation and its inhibition].

Metabolism of membrane-bound and free polyribosomal RNAs was studied under conditions of suppressed synthesis of rRNA induced by small doses of actinomycin D. Besides actinomycin D, cycloheximide was used to suppress the protein synthesis. It was demonstrated that administration of cycloheximide and actinomycin D to rats resulted in a stabilization of membrane-bound polysomal mRNA in liver cells. Simultaneously with the action of those antibiotics, free polysomal mRNA was shown to degrade in exactly the same way as in the liver of control animals. Study of poly-A-containing mRNA metabolism showed that during the first hour following rat labelling specific radioactivity of membrane-bound polysomal mRNA was higher than that free polysomal mRNA. Within the interval of 1-5 hours after labelling specific activity of mRNAs of both polysomal fractions reached the same level. In the cell-free system of protein synthesis the membrane-bound polysomes of rat liver cells appeared to be much more active as compared to the free ones. The addition of poly-U matrix to the cell-free system of protein synthesis significantly stimulated the free polysomes activity during 14C-phenylalanine incorporation into polypeptides. Interrelationship of mRNAs of membrane-bound and free polysomes in eucaryotic cells is discussed.


[Phenolic inhibitor of a proteinase from buckwheat seeds].

An inhibitor of a proteolytic enzyme (BAPAse), hydrolyzing N, alpha-benzoyl-DL-arginine-p-nitroanilide (BAPA), has been found in the buckwheat seeds. The inhibitor is located in the seed coat. The inhibitor is shown to have a phenolic nature and, probably, is a proantocyanidine.


Effect of methoxyflurane anesthesia on serum uric acid in man.

Serum uric acid levels were significantly increased on the first and third postoperative days following methoxyflurane anesthesia in subjects undergoing various surgical procedures. The increment on each of these days was significantly correlated with the duration of the anesthesia. No such changes were found following halothane or nitrous oxide-oxygen and relaxant anesthesia.


Stimulation of macrophage DNA synthesis in culture by different types of acute non immunological inflammatory exudates.

Acute non immunological inflammatory pleural exudates provoked by four different irritants and collected 4 hours later have been shown to be capable of stimulating DNA synthesis, in rat peritoneal macrophages in culture. It is postulated that a mitogenic factor, "Inflammatory Mitogenic Factor for Macrophages" IMF (M), could be responsible for this phenomenon. There may be a correlation between the protein concentration of the exudates and its mitogenic activity.


Mammary carcinogenesis in (C3H X RIII) F1 mice under different experimental conditions.

In (C3H X RIII) F1 females a disturbed hormonal balance plays the major role for the etiology of mammary carcinomas. Castration early in life delays the appearance of the tumors. In normal females the adrenal secretions do not intervene in carcinogenesis. In forced bred females or in animals with pseudopregnancies, but not in mothers which nursed their offspring the latencies are shortened. After a graft with one male pituitary to a castrated female the latency is the same as in intact animals. Pituitary grafting to castrated males does not change the frequency or the latencies of spontaneous mammary cancers. One mammary cancer was observed in an intact male implanted with a pituitary. It is stated that in our animal model progesterone is not an essential factor for mammary carcinogenesis.


Rheumatic symptoms in Crohn's disease and the HLA system.

The study of the distribution of the HLA phenotypes among 55 patients suffering from Crohn's disease did not show any significant difference compared to a control population. On the other hand, the same study limited to patients suffering both from Crohn's disease and peripheral articular manifestations showed a significant increase in the frequency of the HLA BW17.


Intracellular rotation and the phototropic response of Phycomyces.

Experimental evidence indicates that during phototropism, Phycomyces sporangiophores use their own net rotation to convert an apparently spatial stimulus to a temporal one. Conversion to a continuous temporal stimulus insures that phototropism never adapts as long as the spatial asymmetry in illumination is maintained. If this temporal stimulus is circumvented by rotating the cell backwards so that there is no net rotation of some of the receptors relative to the light, the response can be reduced by two-thirds. The system thus adapts to the incident light, resulting in a reduced response. For the illumination of a transparent cell, this compensating rotation speed is 10 degrees/min counterclockwise and probably corresponds to the photoreceptor rotation in the most effective part of the growing zone. We infer that this region is in the upper portion of the growing zone and that the receptor system rotates integrally with that region of the cell.


Thermal excitations of a bilipid membrane.

Propagating modes of vibration of a bilipid membrane have been detected with light beating spectroscopy. The dependence of omega on q is consistent with a model of a fluid film of surface tension sigma = 2.5 +/- 0.5 dyn cm-1 surrounded by a medium with rho = 1 g cm-3 and eta = 1.01 X 10(-2) P.


Gating currents: the role of nonlinear capacitative currents of electrostrictive origin.

The nonlinear capacitative currents deriving from electrostrictive changes of membrane capacitance have been calculated under conditions similar to those employed by Armstrong and Bezanilla (1974) and Keynes and Rojas (1974) in their experiments on gating currents. For values of the parameter characterizing membrane electrostriction in the range suggested by optical retardation studies of Cohen et al. (1971), the nonlinear current of electrostrictive origin is comparable in magnitude and time-course, but is opposite in direction to the observed gating currents. Hence, the a priori neglect of electrostrictive currents is probably not justified. Conversely, if this current is, in fact, negligibly small in real situations, it follows that membrane compressibility must be significantly smaller than has been estimated.


Orientation of chlorophylls within chloroplasts as shown by optical and electrochromic properties of the photosynthetic membrane.

The effects on the optical properties of photosynthetic membranes caused by several types of chlorophyll differing in resonance frequency and in spatial disposition are theoretically analyzed. Using a method of moments and the linear dichroism spectrum of the lamellae, we evaluated the mean angle (phi) between the transition moment of each chlorophyll and the normal to the lamellae. We have confirmed that at about 695 nm the transition moment is in the plane of the lamellae, and outside it for chlorophyll b (phi approximately 48.6 degrees). By integrating over frequency the absorption variations affected by ionophores, we show that they may be ascribed to a Stark effect, and we analyze the dependence of this effect on the orientation of the chlorophylls. From this dependence and the degree of polarization of the Stark effect, we calculate the spatial fluctuations of the angle phi. The calculation shows that a definite value of phi corresponds to each resonance frequency of chlorophyl a found in vivo. This proves that the chlorophylls a are not oriented partly random. For chlorophylls b, on the other hand, phi may fluctuate by some 10 degrees about its mean value. The structural consequences of these results are discussed.


Amphiphile diffusion in model membrane systems studied by pulsed NMR.

The translational diffusion of the amphiphilic molecules in a number of lyotropic liquid crystalline phases has been measured with the pulsed NMR pulsed magnetic field gradient method. The amphiphiles studied were soaps, monoglycerids and lecithins. Measurements were performed both for oriented lamellar and for cubic phases. The order of magnitude of the diffusion coefficients was found to be the same as in neat liquids of analogous compounds. It was also found that the difussion coefficient depend markedly on the amphiphile end group in a way that parallels the area per polar head group as determined in X-ray studies. When corrections for geometrical factors has been made the diffusion rate is approximately equal in cubic and lamellar phases containing the same amphiphile.


A new mechanochemical method of enzyme immobilization.

A new mechanochemical method for enzyme immobilization has been elaborated. The principle of this method consists of the following precepts. Partially hydrolyzed nylon fiber, the surface of which is known to be strewn with microcracks, is reversibly stretched (approximately 25%) and placed into an enzyme solution. Then, in the same solution, the fiber is made to relax and is taken out. The fiber retains considerable enzymatic activity even after numerous thorough washings (in a similar procedure without fiber stretching, equivalent washing removed all the enzymatic activity from the fiber). Immobilization on the fiber proceeds due to trapping of enzyme molecules by the microcavities on the surface of the support. The catalytic activity of mechanochemically immobilized chymotrypsin and trypsin is commensurable with their activity on covalent immobilization on nylon (calculated per unit of the macrosurface). A wide range of commercial polymers may be made of use as supports in the mechanochemical method of immobilization.


Computation of the fraction of induced cells in enzyme induction systems.

A theoretical model is developed for continuous multistage enzymed production systems, which consist of a growth fermentor used for growing microorganisms rapidly without enzyme production and a subsequent system of induction reactors in which enzyme induction and production occurs. The model allows the computation of the fraction of induced cells residing in the induction reactors for organisms exhibiting a lag phase in enzyme induction. For this model a general analytical solution was obtained for the cumulative internal residence time distribution of a series of n well-sterred vessels with a recycle. The theoretical results are compared in a preliminary way with experimentally measured cellulase productivities of continuous multistage cellulose fermentations with Trichoderma viride QM 9414.


The tubular loop fermentor: oxygen transfer, growth kinetics, and design.

Oxygen transfer measurements using a dynamic method and evaluated with an appropriate mathematical model have been made on a tubular loop bioreactor, Correlations of the type used in tank systmes are used to describe the influence of power and aeration rate on the mass transfer coefficient. Yeast cultures grown on hydrocarbon and glucose substrates show growth characteristics similar to conventional tank results. Model considerations for large-scale tubular fermentors allow for the prediction of the steady-state oxygen profiles and maximum reactor length. Combination with two-phases flow and oxygen transfer correlations yields a design procedure for commercial scale tubular loop fermentors.


[Use of local electromyography for revealing conductivity along efferent pathways in patients with traumatic lesions of the spinal cord ].

Electrical activity of the gastrocnemius and of the tibial muscles were examined in the patients with the spinal cord trauma during the active strain to extend or to flex the foot; action potentials of the motor units (MU) were recorded in a number of these patients during the mentioned volumtary efforts, despite the absence of interference electromyogram (EMG). A voluntary MU activation led to the conclusion on a possibility of detection by the local EMG method of the efferent conductivity partially persisting after the trauma along the spinal cord route.


[Characteristics of temporal and spatial parameters of voluntary (set) human respiratory movements under conditions of chemorecptor stimulation of different character].

Dynamics of temporal and spacial parameters of set respiratory movements (in comparison with the movements of the hand) under conditions of progressive hypoxia, hypercapnia, hypoxic-hypercapnic interaction was investigated in 10 men aged from 19 to 30 years. Hypercapnia (especially in combination with hypoxia) is a specific factor preventing voluntary control of the respiratory movements. The certitude (exaggeration of the set respiratory volume) and the capacity to correction of the respiratory movements are mostly influenced by these factors. These facts are considered to be the result of chemoceptor stimulation of the respiratory center (imperative stimulus).


[Effect of nonachlazine and oxyfedrine on coronary circulation in dogs].

Coronary circulation was measured in the anesthetized and nonanesthetized dogs by means of ultrasonic Doppler's radiotelemetric apparatus. The ultrasonic pick-up was placed on the upper third of the descending branch of the left coronary artery. Nonachlazine considerably increased the coronary circulation in the anesthetized and nonanesthetized dogs. However, the action of the preparation lasted 2 to 3 minutes only and depended on the changes in the cardiac activity. In difference from nonachlazine, oxphedrine increased the coronary circulation to a lesser degree, but for a much longer time (20min on the average). Taking into consideration a high efficacy of these preparations under clinical conditions a conclusion was drawn that an increase of the coronary circulation was not the principal way of action for reaching the antiangina effect in the patients with ischemic heart disease.


[Role of hyperactive determinant structures in the creation of functional complexes of seizure activity in the cerebral cortex].

Experiments were conducted on cats; foci of increased excitability working in the individual activity regimens were created by the subconvulsive strychminization. A focus of more powerful excitation induced also by means of strychine played the role of a determinant dispatch station (DDS). Its importance consists in determining the character of the other excitation foci activity in enhancing the excitation in them, in uniting them into a functional complex, and in determining the character of the whole complex activity. This complex can be destroyed by nembutal suppression of DDS. Exclusion of any other destination stations included into the complex failed to effect this complex.


[Induction of lung tumors in mice using diamylnitrosamine].

Mice of the CC57W strain were treated subcutaneouly with diamylnitrosoamine in a dose of 0.025 ml per mouse. once a week, 17 doses in all. These mice were sacrificed 27 weeks after the beginning of the experiment. Lung tumours, mainly adenomas, and in 3 cases adenocarcinomas, were detected in 14 of 17 mice which died and in 24 sacrificed mice. Besides, a marked proliferation of the interstitial tissue of the kidneys in a pretumor state, nephroblastoma, carcinoma in situ, and invasive cancer of the urinary bladder, one of each tumour, were found. Thus, diamylnitrosoamine can be recommended for induction of experimental lung tumours in mice.


[Inhibitory effect of a number of substances on manifestation of the embryotoxic and teratogenic effects of methylurea and sodium nitrite].

Embryos died and a teratogenic effect followed combined intragastric administration of methylurea (MU) and sodium nitrite (SN) to rats on the 9th day of pregnancy; this was caused by the endogenous synthesis of nitroso-methylurea which produced a pathogenic action. Ascorbic acid and urotropine completely blocked the possibility of manifestation of the embryotoxic and teratogenic effect occuring after combined administration of MU and SN. Sodium sulfomate decreased the embryotoxic and partially the teratogenic effect considerably, whereas urea failed to prevent the expression of the harmful effect of MU and SN on the embryo.


[Stimulation of post-traumatic regeneration of rat spleen under conditions of gravitational stress].

Post-traumatic regeneration of the rat spleen was studied after resection of half the organ, under gravitation overloading (11 units) using spleen tissue extract prepared by Filatov's method. Gravitation overloading caused a decrease in the size of the spleen nodules, smooths their contours, increases the red pulp infiltration by the lymphocytes, reduces the number of labeled cells and the intensity of the label in the reactive centers of the spleen nodules, decelerates the capsule formation in the resection area. Application of the stimulant normalized the structure of white pulp, increased the number of labeled cells, and accelerated the capsule formation. The tissue extract used in gravitation overloading brought the restoration process nearer to the usual course of the posttraumatic spleen regeneration (by the character and periods of tissue differentiation development).


[Physico-chemical properties of the DNP-systems of leukemia cells with different chromosome numbers].

The binding between the components of the isolated DNP-complex proved to be more stable in leukemic cells in comparison with the normal lymphoid spleen cells. This conclusion was based on the investigation of the thermomechanical and disaggregation properties of the supramolecular DNP systems isolated from leukemic cells. The change in the isolated DNP-complex were independent of the subpopulation variants of the leukemic lymphatic cells and their chromosome set (diploid or hyperdiploid). The observed changes in the chromatin properties were more specific for leukemic cells than the changes in thechromosome number.


[Planimetric grids for macro- and microscopic stereologic studies].

The authors suggest a lattice variant for the planimetric investigation of the macro- and microobjects, with the equal distance between the lattice main points which had a 'zero' thickness. The method of stereological studies is described. Formulae for the determination of the necessary number of counts of the points for obtaining the representative data on the quota of the structural components in the sample under study at the 95% confidence interval are suggested. Formulae for the estimation of the volumetric density of the structural formation under study in the macro- and microscopic object with the calculation of its statistical indices are given.


[Effect of prostaglandin Bl on systemic and regional hemodynamics].

The effect of prostaglanding B1 (PGB1) on the cardiovascular system of dogs was studied in experiments on anesthetized dogs. The intravenous injection of PGB1 (40 microng/kg) was followed by aortic hypertension, tachycardia, an increase of myocardial contractility, an enhancement of minute volume of the heart, and in increase of arterial pressure in the pulmonary artery. Total peripheral resistance and total lung resistance were reduced. The work of the left and the right ventricles and the coronary flow increased (the latter by 29%). The average voluminous blood flow velocity in the femoral and the superior mesenteric arteries increased significantly, while in the common carotid and the renal arteries--insignificantly. The observed changes in the systemic and regional hemodynamics were of short duration.


[Circulating blood volume and its respiratory surface under conditions of cranio-cerebral hypothermia].

Experiments were conducted on dogs; a study was made of the effect of cranio-cerebral hypothermia on the circulatory blood volume and its respiratory surface. A reduction of body temperature from 36 to 30 degrees C led to the increase of the circulating blood volume from 62.4 +/-2.18 ml/kg to 65.2 +/- 6.95 ml/kg, of the circulating erythrocytes from 27.3 +/- 1.43 ml/kg to 33.8 +/-3.78 ml/kg. Further cooling reduced these indices to 40.7 +/- 3.12 ml/kg and 24.2 +/- +/-2.14 ml/kg, respectively. Plasma starts to leave the vascular bed simultaneously with the beginning of cooling. Its volume decreases with the fall of temperature from 36 to 24 degrees C from 34 +/- 1.07 ml/kg to 16.6 +/-1.19 ml/kg.


[Effect of exogenous superoxide dismutase and 1,4-diazobicyclo-(2,2,2,)-octane on the resistance of mice to acute oxygen poisoning].

Single injection to mice of a perified preparation of superoxide dismutase (1000 units, intravenously) combined with catalase (0.5 mg) or without it failed to protect from the toxic action of 100% oxygen under the pressure of 5 ata. 1,4-diazobicyclo (2.2.2) octane (6 mg, intraperitoneally) increased the preconvulsive survival period of mice under these conditions. The formation of single oxygen under hyperoxia in vivo is supposed.


[Blood coagulation upon contact between blood and polymeric materials possessing electretic protperties].

Hemocoagulation peculiarities were studied on polymeric materials with the electretic properties. Negative polarity of the electretic polymeres promoted fibrinogenemia and hypoadhesia of platelets in comparison with the electretic materials with positive polarity and polymeres possessing no static electricity. It is supposed that fibrin sorption and platelet hyperadhesion played the main role in thrombogenesis on implanted polymeres.


[Effect of acetylcholine and atropine on renal secretion of blood-clotting compounds into the bloodstream].

Experiments with perfusion of the kidneys in situ in cats demonstrated that excretion by the kidneys into the circulation of the coagulation factors and fibrinolytic agents could be regulated. Acetylcholine decreased the release into the circulation of the hemocoagulating agents and of the antiheparin compounds, but increased the discharge of plasminogen activators from the kidneys. Atropine stimulated the release from the kidneys of tromboplastic agents and antiheparin components, but decreased the excretion of antithrombin compounds. Atropine intensified the fibrinolytic activity of the perfusate insignificantly.


[Allergenic characteristics of chemical compounds migrating from polymeric building materials].

The authors worked out the technique of determining the allergenic activity of the volatiles migrating into the air medium from polymer building materials (PBM). The methods of allergodiagnosis in vitro (the passive hemagglutination test, specific leukocytic agglomeration test, intensification of leukocyte pyroninophilia test) were used to detect sensitization in experiments on guinea pigs. It appeared that PBM could cause atopic allergie reaction under certain dwelling conditions.


[Migration of hepatocytes in liver cords during physiologic regeneration].

Distribution of mitoses and dead hepatocytes in the hepatic balk was investigated. A relative rate of the hepatocyte movement along the hepatic balk was calculated on the basis of this distribution. The direction and the rate of the hepatocyte movement along the hepatic balk were determined by measurement of the shift of the labelled cell peak a month after six thymidine-H3 injections.


[Electron-cytochemical study of acid phosphatase in the brain after death].

The activity of acid phosphatase in the rat and human brain was determined by the electron-cytochemical method. Lysosomes and lipofuchsin granules proved to possess enzymatic activity. Use of postmortem material showed the localization of acid phosphatase to remain unchanged at the remote periods after death.


[Development of interneuronal synaptic junctions in neuroblasts of the anterior horn of the spinal cord during early prenatal human ontogenesis (7--9 wks. of pregnancy)].

A method of electron microscopy was applied to the study of the synaptogenesis in the presumptive ventral horns of the spinal cord (C4--Th3) at the early prenatal human ontogeny. The morphological stages of synaptogenesis were traced, and the minimum of the structrual organization of the synapse, correspoding to the beginning of its functional activity, was determined. A hypothesis is put forward on possible mechanisms of synaptogenesis.


[Changes in the accessory group of hypothalamic neurosecretory cells following stimulation of the supraoptic nucleus].

Changes of an accessory neurosecretory cell group were investigated in acute experiments on cats under chloralose anesthesia. The unilateral stimulation of the supraoptic nuclei (with vasoconstrictory effect) caused activation of cells of the accessory group at the side of stimulation, and increase of the nucleolar size. No changes in the paraventricular nuclei were observed, whereas cells of the supraoptic nuclei were activated. The identity of the main and the accessory neurosecretory group reaction and literature data on histochemistry suggest that both cell groups produced vasopressin stored in the posterior lobe of the hypophysis, and acted partially as a mediator outside the hypothalamus.


[Experimental toxic pulmonary edema in white mice with influenza].

Toxic pulmonary edema during influenza developed 3 hours after infection of mice with concentrated influenza viruses adapted to lung tissue. The toxic viral action is expressed in filling the alveoli with fluid exudate, by stasis in the pulmonary vessels, by eosinophilic necrosis of the epithelium in the bronchioles, and also by destruction of cells of the cortical layer of the thymus. The elaborated model aids in the understanding of malignant forms of influenza infection in man resulting in death.


[Method of studying the microcirculation of the sciatic nerve during life].

The authors describe a mehtod of bloodless exposure of the sciatic nerve in rats, of placing it on the light conductor, and of the preparation of microscope MBI-6 for the intravital study of microhemocirculation in the epineurium of the sciatic nerve. Different types of the microvessel network of rat are demonstrated.


[Quantitative assessment of cutaneous erythema].

On the basis of general concepts on the objective nature of colour perception and colourimetric tables of the colour atlas special colourimetric rulers were elaborated for the assessment of skin erythema. These rulers can be used for the assessment of experimentally-reproduced common and allergic inflammations of the skin in acute and chronic diseases. The system of assesment take into consideration the experience of the grade characteristics of inflammation of the skin, with the description of erythema with the aid of clear physical colour parameters: brightness (p, %), the wave length (lambda, nm) and the saturation (P,%).


[Change in systemic hemodynamics under the influence of vasopressin in dogs during ontogenesis].

Experiments were conducted on dogs (18-22 days, 2-3-month-old and adult). The central hemodynamics indices were studied after intravenous administration of 0.8 U/kg of synthetic vasopressin. The pressor effect was mostly expressed in adult dogs, and bradycardia--in 18--22-days-old puppies. All dogs displayed an increase of the total peripheral resistance accompanied by reduction of the minute output. External work of the left ventricle and expenditure of the energy by the heart rose in adult dogs. As to puppies, a reduction of the cardiac output and of the external heart work was accompanied by a lesser increase of energy expenditure.


[Interrelationship of changes in central hemodynamics in the postresucitation period with development of posthypoxic cerebral edema].

A syndrome of low cardiac output developed between the 1st and the 3rd hours after the resuscitation in 16 dogs after the arrest of blood circulation for 15 minutes. The increase of cardiac output at the initial period of resuscitation took place in 50% of cases before the development of this syndrome. In the absence of hyperperfusion at the beginning of the resuscitation the animals died 9 to 23 hours after the experiment. Cerebral cortex edema developed in all the survived dogs which had low cardiac output 24 hours after resuscitation, but it was not observed in animals with high cardiac output.


[Cytotoxic effect of lymphocytes on peritoneal macrophages of mice in contact dermatitis induced by dinitrochlorbenzene].

Contact dermatitis was induced in BALB/c mice by means of cutaneous application of dinitrochlorbenzol (DNCB) solution. Peritoneal macrophages from DNCB-sensitized and intact mice were cultivated in flat tubes for 48 hours after the 20th day of the experiment, when the DNCB cutaneous test became positive. A suspension of the peripheral lymph node lymphocytes was added to this culture. The lymphocytes fromthe DNCB-sensitized mice had a cytotoxic effect (CTE) on the target cells (peritoneal macrophages) during the co-incubation; the STE was tested with trypane blue in 48 hours. No macrophage lysis was observed in combined incubation of cells from the intact mice.


[Isolation and properties of an actomyosin-like protein from bovine brain glial cells].

Actomyosine-like protein (AMLP) was isolated from the enriched glial fraction of the bovine brain cortex. The AMLP yield constitutes 0.05% of protein in the glial cells. The AMLP contained nucleotides; there were reversible association-dissociation reactions under the effect of Mg2+ ions and ATP characteristic of AMLP. ATP-ase of glial AMLP, activated with Ca2+ ions more than with Mg2+ ions, differed from AMLP of neuronal origin.


[Several kinetic features of membrane-dependent monoamine oxidase].

The v versus (S) plots for the initial rates of serotonin oxidation, catalyzed by monoamine oxidase in fragments of the rat liver or bovine brain mitochondrial membrane, had complicated non-hyperbolic shape, suggesting kinetic manifestation of cooperation in binding the substrate by the enzyme. A possibility of interactions of different monoamine oxidase types via the conformational alterations in the bio-membrane itself is considered.


[Antagonistic effect of bicuculline and thiosemicarbazide on the tranquilizing effects of diazepam].

It has been shown that bicuculline--GABA-ergic receptors specific blocking agent in doses of 0.5 and 1.0 mg/kg (subcutaneously), and thiosemicarbazide (inhibiting the brain GABA synthesis) in dose of 5.0 and 8.0 mg/kg (subcutaneously) were capable of antagonizing diazepam effects and of reducing its tranquilizing activity in an experimental test of conflict behavior in rats. Bicuculline exhibited a more pronounced antagonism to diazepam than thiosemicarbazide. The data obtained testified to a possible involvement of the GABA-ergic mechanisms in the realization of the anxiolytic effect of benzodiazepines.


[Effect of nonachlazine on the frequency and amplitude of isolated atrium contraction].

The effect of nonachlazine, a new antianginal drug, on the rate and the amplitude of contractions of the isolated auricle was studied on guinea pigs and albino rats. Unlike the experiments conducted on intact animals, in the experiments on the isolated auricle nonachlazine proved to decrease the above-mentioned indices. This effect of the drug in the case of the isolated auricle is likely to be due to the ability of nonachlazine to cause a direct effect on the myocardium and the conductive heart system. No specific distinctions in the character of nonachlazine action were revealed.


[Antibodies to heart valve fibroblasts in the sera of rheumatic patients].

The antibodies reactive in immunofluorescence with the fibroblasts of human and bovine heart valves were isolated from the rheumatic patients' sera with the aid of immunoadsorbent prepared from human heart valve tissue. No reaction between the antibodies and the fibroblasts of the interstitial connective tissue of the myocardium was observed. It seems that the fibroblasts of the heart valves and the myocardium contain different antigens; the presence of common antigenic components in human and bovine valve fibroblasts is shown.


[Role of allergic responses of peripheral blood leukocytes in the pathogenesis of experimental allergic (pertussis) encephalomyelitis].

Stable leukocytosis and lymphocytosis were observed in the peripheral blood of guinea pigs from the 14th day after their sensitization with B. pertussis oil suspension. A shift to the left occurred in the leukocytic count. After the contact of leukocytes with the specific cerebral antigen both in vivo and in vitro leukolysis and allergic alteration of leukocytes which occurred at the last stages of sensitization i.e. at the period of clinical manifestation of the experimental allergic encephalomyelitis (EAE) involved mainly the granulocytes. These phenomena are supposed to be caused by the anticerebral antibodies which appear in the blood at this stage of EAE, i.e. in the mechanism of development of EAE allergic reactions of the immediate type in combination with allergic reactions of the delayed type.


[Changes in several properties of transplantable adenocarcinoma of the large intestine during passage].

In the course of serial passages of adenocarcinoma (AKTOL), arising from fetal colonic tissues which underwent spontaneous malignization after being grafted to syngeneic adult mice, there was an increase in the rate of growth of the subcutaneous transplants, and multiple intrapulmonary tumour nodes formed after its intravenous inoculation (the first transplant generations had no such capacity); the morphological anaplasia of the tumour increased. These changes were not directly dependent on the changes in its immunogenicity.


[Effect of a hemolysate from polycythemic animals on proliferation on bone marrow cells].

Erythrocytic inhibitor from the polycythemic rats depressed the mitotic activity of the cells of the erythroid series in mice by 40%. The inhibitory effect lasted about 12 hours. The inhibitor acted on the G2-period. Not only the blast forms of the erythron, but also the stem hemopoietic cells served as the points of the inhibitor "application".


[Influence of a series of substances from the group of chlorine-derivative hydrocarbons on the composition of a population of rat liver hepatocytes].

The cytophotometric and kariometric study of the liver hepatocytes in albino rats inhalationally exposed to dichlor- and trichlorpropan showed the latter to be more toxic than the former by its effect on the polyploidization of hepatocyte nuclei. The development of polyploidization was determined by the concentration level of the active agent and the length of exposure to it: the lower the concentration--the more time was required for the realization of the effect.


[Comparative study of the effect of etimizol and hydrocortisone on proliferative activity and protein synthesis in epithelial cells of the tongue and liver].

In contrary to hydrocortisone, the stimulating effect of aethymizol on the mitotic activity of the tongue and liver epithelial cells was revealed 6 hours after its injection. Subsequently reduction of the mitotic activity of hepatocytes appearing in 12 hours was caused by the action of both preparations on the DNA synthesis, rather than by disturbed mitosis. Stimulation of protein synthesis by hydrocortisone and aethymizol was shown by the autoradiogrphic and biochemical methods, when the maximum mitoses were inhibited.


[RNA synthesis in cells of the cerebral cortex of mice according to electron-microscopic autoradiography findings].

An electron microscopy autoratiographic study of the RNA synthesis in the neurons of the mouse cerebral cortex revealed the highest label concentration in the nucleoli. A considerable amount of silver grains was concentrated over the nucleoplasm. The content of the radioactive substance in the cytoplasm of the neurons 2 1/2 hours after the animal was injected with 3H-5-uridine was lower than in the other kinds of cells at the same period of their contact with the labeled precursor. A considerable difference in the amount of silver grains was observed over the serial sections of the same nucleolus and in the way of the label distribution in the neurons located nearby.


[DNA concentration and magnitude of cell nuclei in regenerating rat liver].

The DNA content in individual nuclei and the size of cell nuclei in the intact and regenerating liver 18 hours to 21 days after partial hepatectomy were studied in rats. In the intact rat liver most nuclei were found with a mean DNA content in the nucleus of 6 pg; as to the nuclear size--it was about equal to the size of the diploid nucleus (42.5 micronm2). In the regenerating liver DNA synthesis started before the 18th hour after partial hepatectomy. In most of the nuclei the DNA content by the 24th hour was found to be double that in intact animals, indicating a 85-90% engagement of hepatocytes by the first synthesis wave. After mitosis occurring in most cells before the 36th hour after partial hepatectomy much milder DNA synthesis waves followed at the 42nd and 60th hours.


Evidence for differentiation of human leukemic blood cells in diffusion chamber culture.

Peripheral blood cells of 21 patients with different forms of acute leukemia were cultured in diffusion chambers (5 x 10(5) cells/chamber) implanted intraperitoneally in 650 R preirradiated host mice over a period of up to 21 days. In patients with acute myeloid leukemia (AML), acute erythroleukemia (AEL), or acute myelomonocytic leukemia (AMMoL), the total number of cells which developed during this culture period exceeded the implanted value and also the values for normal peripheral blood cells from ten controls. In acute undifferentiated leukemia (AUL), two out of six patients showed considerable growth whereas the others, and also two patients with acute lymphoid leukemia (ALL), had poor growth. Differential counts revealed that the rise in total cells was due mainly to proliferation of blast cells and formation of granulopoietic cells. The latter exceeded the numbers from normal peripheral blood cells in 9 out of 13 patients with AML, AEL, or AMMoL and in 2 out of 6 patients with ALL. The production of granulopoiesis was not restricted to proliferating cells, but included mature cells which were of abnormal morphology in some cases. From the amount of granulopoiesis and the time of its development it was assumed that they were at least partly derived from leukemic blast cells. Chromosome analyses to decide whether the granulopoietic cells were of leukemic or normal cell origin are in progress.


Circulating anticoagulant in a family with prolonged bleeding time and factor VIII deficiency.

A circulating anticoagulant against factor VIII activity was demonstrated in the plasma of a boy from a family with both factor VIII deficiency and prolonged bleeding time. However, the factor VIII-related antigen, ristocetin-induced platelet aggregation activity, platelet retention in glass bead columns, platelet aggregation with adenosine 5'-diphosphate, collagen and epinephrine, and clot retraction among affected members were normal. The electrophoretic mobility of factor VIII-related antigen on crossed immunoelectrophoresis was normal. The inactivation of factor VIII activity by the inhibitor was time dependent and was nonlinear as the concentration of the inhibitor was increased. Immunotyping showed that the inhibitor was IgG with k light chains.


Factor V activity of platelets: evidence for an activated factor V molecule and for a platelet activator.

This study was prompted by the observation that fresh platelet suspensions--prepared by gel filtration or albumin density gradient centrifugation--possessed only minimal factor V activity, whereas frozen-and-thawed platelet suspensions possessed striking factor V activity. Results of experiments with fresh suspensions suggested that unaltered platelets did not bind plasma factor V. The factor V activity of frozen-and-thawed platelet suspensions was markedly diminished after exposure to a factor V antibody, was not activated by thrombin, and was not associated with an increase in factor V antigen over that found in fresh platelet suspensions. Consequently, disruption by freezing and thawing must have resulted in the appearance of small amounts of an activated factor V molecule in platelet suspensions. Disrupted platelets were shown to activate native factor V, but an interaction between a platelet activator and traces of native factor V in fresh suspensions could not be demonstrated to account for the full activity of frozen-and-thawed suspensions. Apparently, therefore, platelets also contained an activated factor V molecule. Adding collagen, but not adenosine 5'-diphosphate to fresh platelet suspensions increased their factor V activity. Release of an activated platelet factor V molecule after exposure to collagen could represent a physiologically significant early step in hemostasis.


Effects of ascorbic acid and its 2-sulfate on rabbit aortic intimal thickening.

Effects of intravenously injected L-ascorbic acid or L=ascorbic acid 2-sulfate on aortic intimal thickening were examined histologically, qualitatively, and quantitatively in the upper, middle and lower thoracic aortic positions of cholesterol-induced atherosclerotic rabbits. A means of evaluating the degree of pathology of the aortic positions was developed employing five descriptive statistics of intimal thickening. Both L-ascorbic acid and L-ascorbic acid 2-sulfate inhibited intimal thickening. The most significant reductions were observed in the upper thoracic aorta.


[Decreased flexibility of newborn infant erythrocytes].

The rheological properties of erythrocytes of 10 full-term infants were studied. A method of filtration and measurements of viscosity of erythrocyte suspensions with a hematocrit of 80% were used. Erythrocytes of newborn infants were less flexible than erythrocytes of healthy adults. Rigidity of erthrocytes was due to an increased hemoglobin content of the erythrocyte membranes which was measured in isolated ghosts. After incubation of the cells with acetylphenylhydrazin Heinz-bodies were formed in the erthrocytes of adults. The flexiblity of these cells decreased markedly. More Heinz-bodies were found in the erythrocytes on the newborn infants, when their cells were incubated under identical conditions. These erythrocytes became more rigid than the erythrocytes of adults. From these results we conclude that the more rigid erythrocytes of the newborn infants would not pass the splenic sinus, especially when they contain Heinz-bodies. The rheological properties of the erythrocytes of newborn infants explain the shortened life-span of red cells of newborn infants.


Reduction of mercury, copper, nickel, cadmium, and zinc levels in solution by competitive adsorption onto peanut hulls, and raw and aged bark.

The competitive adsorption of common heavy metal ions by peanut hulls, raw bark, and composted bark was studied. These solid wastes were found to adsorb significant amounts of one or more of the heavy metals (Hg, Cu, Ni, Cd, Zn) commonly found in municipal sludge and wastewater.


Smoking in pregnancy: some notes on the statistical controversy.

The statistical evidence for a relationship between pregnancy smoking, birthweight, and perinatal mortality is critically examined. Some apparent discrepancies between and within different studies are resolved.


Academic performance and social factors related to cigarette smoking by schoolchildren.

Factors which may influence boys and girls aged between 10 and 121/2 years to start smoking were studied. Information was obtained from 491 schoolchildren, their parents, and headteachers. In their own view and that of their headteachers children who did not smoke were academically better than smokers. Children who smoked were more likely than non-smokers to have a parent and siblings of the same sex who smoked. No association was found between the child's own smoking and that of parents and siblings of the opposite sex. Smokers were more likely to have friends who smoked. Most children did not think smoking was enjoyable or desirable and many thought it bad for health, irrespective of their own smoking habits. The majority thought people of their own age smoked to show off.


Temperature and deaths from ischaemic heart disease.

Certain features of the relationship between 11 measurements of weekly temperature and the number of deaths from ischaemic heart disease (IHD) within age groups in Greater London between 1970 and 1974 are described. Firstly, the correlation coefficients between age-specific deaths from IHD and each of the temperature variables are of a similar order. Secondly, in contrast, the linear regression coefficients between deaths and temperature are more variable and depend upon the particular measurement of temperature chosen. Thirdly, the proportional changes in the number of deaths with the temperature variables are similar within specific age groups; consequently it is suggested that deaths from IHD and temperature may be directly related.


An epidemiological study of congenital reduction deformities of the limbs.

A retrospective study that was undertaken to determine why more infants had been born with congenital reduction deformities of the limbs is reported. The increase was detected by the Congenital Anomaly Surveillance System in 1969. Ninety-three infants born in Alberta and British Columbia in 1969-71 with congenital reduction deformities were matched with 93 normal infants and 93 infants with congenital malformations of a different type. The mothers of all infants were interviewed to obtain information on factors thought relevant to the establishment of a causal relationship. Although there were some significant differences between cases and normaland/or abnormal controls, this number of differences might have been expected by chance. No single causal relationship was established.


Daily mortality and environment in English conurbations. Air pollution, low temperature, and influenza in Greater London.

With the decline in concentrations of suspended particulate pollution in Greater London the association seen in the 1950s and early 1960s between daily mortality and air pollution in the conurbation is no longer apparent. Associations between unusually cold weather and short-term increases in mortality have been noted; there appears to be a tendency for influenza epidemics to follow cold spells.


An explanation for the observed increase in mortality after a birthday in people over 75 years old.

In a recent analysis, Alderson (1975) presented data that suggested a statistically significant, although numerically small, relationship between the month of birth and the month of death of elderly people. It is shown here that this relationship was to be expected from the sampling procedure used and was not related to "birthday stress" factors.


Inappropriate constancy scaling as a factor in the Müller-Lyer illusion.

The inappropriate constancy theory of geometrical illusions assumes the existence of implicit depth cues which automatically set constancy scaling. In the present study the phenomenon of cue conflict has been employed to test for latent depth cues in the Müller-Lyer figures. The technique consisted in introducing a stereoscopic disparity between the figures by means of an aniseikonic lens and measuring the perceived depth between the figures. The magnitude of the stereoscopic effect depends on whether the perspective cues augment or inhibit the stereoscopic depth cues. The results were inconsistent with the misapplied constancy theory, but confirmed Pike & Stacey's (1969) observation that the illusion of size may act as a depth cue.


Aortocaval fistula as a complication of leaking aortic aneurysm.

The successful management of 2 patients is reported, each involving the closure of a fistula into the inferior vena cava as a sequel to the rupture of an atherosclerotic aortic aneurysm. It is an uncommon complication which should be suspected in the presence of an aortic aneurysm with a loud machinery bruit. Associated peripheral cyanosis and venous pulsation in the accessible proximal veins of the lower extremity and priapism afford strong supporting evidence.


Drug consumption before perforation of peptic ulcer.

In a retrospective study of 195 patients with a perforated peptic ulcer 18 per cent of the patients had taken aspirin, phenylbutazone or corticosteroids during the period before the perforation. In a controlled prospective trial, 18 of 22 patients (82 per cent) had taken drugs known to be potentially harmful to the stomach. Aspirin was the drug mainly used. Thirteen of 22 patients had taken the drugs within 12 hours of the perforation, usually because of symptoms not related to the gastro-intestinal tract. Drug consumption and perforation of pre-pyloric ulcers were most closely associated; the latter applies particularly to female patients, who either had only a short history of upper gastro-intestinal dyspepsia or were asymptomatic.


Surgical treatment of sclerosing peritonitis caused by practolol.

A detailed and illustrated account is given of the surgical operation needed to treat practolol-induced sclerosing peritonitis, based on the personal experience of 6 patients.


Zinc metabolism and surgical trauma.

Several investigations have shown that zinc deficiency impairs wound healing in surgical wounds and in chronic ulcers. It is also well established that surgical trauma produces a sharp decrease in serum zinc concentration. It has not been clearly shown that this decrease is due to a rise in urinary excretion. In the present investigation the relationship between urinary zinc excretion and the fall in serum zinc postoperatively was studied in 38 patients. Older patients usually had low preoperative serum zinc concentrations. Preoperative zinc substitution is therefore suggested for such patients.


Dangerous reactions to treatment of onchocerciasis with diethylcarbamazine.

Nine Nigerians with severe onchocerciasis who were treated with diethylcarbamazine developed clinical changes, ranging in severity from mild itching to distress, cough, and syncope. Physiological changes (fever, tachypnoea, tachycardia, or hypotension) were seen in eight. In five patients the systolic blood pressure fell by more than 25 mm Hg, and one patient collapsed on attempting to sit up. Circulating eosinophils decreased profoundly in all cases, reaching their lowest levels just before or during the clinical and physiological changes. A fall in serum complement (c3) accompanied the reaction but there was no fall in antibody titre. Diethylcarbamazine probably acts on the parasite's cuticle, thus exposing it to the body's defence mechansims. The reaction coincides with the death of microfilariae, and the accompanying physiological changes may be so severe, even in generally healthy patients, the treatment should perferably be started in hospital.


Feeding of school children in a London borough.

A survey of 12 schools in a London borough showed that the protein and energy content of the average school meal was below the standard set by the Department of Health and Social Security for all age groups. Failure to meet the standards resulted from inadequate food purchases, poor menu planning and portion control, and several management problems. A 24-hour recall questionnaire showed that 5% of the pupils were "poorly" fed. These pupils were, however, no worse off than their "adequately" fed peers with regard to absences from school or academic attainment measured by reading quotient, but there was some slight difference in height and weight. The percentage of children having no breakfast increased from 4% in the infant schools to 21% in the senior schools. Two per cent of the senior pupils regularly ate no lunch.


Paediatric home nursing scheme in Gateshead.

A scheme to provide specialised nursing care for sick children in their own homes was begun in Gateshead in 1974. Selected district nurses were retrained in the paediatric unit on which the scheme was based and nursed at home 22 children referred to them by general practitioners as the alternative to hospital admission and 39 discharged to their care by the hospital. Most of the children were aged 3 years or less and came from working-class homes. Most of the mothers who were asked were in favour of the scheme.


Deliberate self-poisoning: a study in London casualty departments.

During a prospective study of the whole spectrum of drug-related problems treated in one month by 62 casualty departments in the Greater London area, 949 cases of deliberate self-poisoning were identified. Nearly three-quarters of the patients were under the age of 40 years and in all age groups women outnumbered men. Psychoactive drugs of some sort were used in 673 incidents (71%) and ordinary analgesics and other drugs were used in 252 (27%). The incidence of polydrug overdose (423; 45%) was much higher than that found in other studies. In at least 256 incidents (27%) there was a history of repeated overdose in the previous 12 months. Comparison with other studies showed a steady decline in the use of barbiturates in deliberate self-poisoning but an increase in the use of non-barbiturate hypnotics, minor tranquilisers, and antidepressants.


Evaluation of fetal wellbeing by antepartum fetal heart monitoring.

The value of antenatal fetal heart rate monitoring was assessed in 301 patients. Tracings from each patient were classified as "reactive" or "non-reactive." Perinatal mortality, fetal distress in labour, caesarean section for fetal distress, and the incidence of low Apgar scores were all significantly increased in the non-reactive group.


Sex-related differences among 100 patients with alcoholic liver disease.

During 1975 we studied 100 patients--77 men and 23 women--who had a history of alcohol abuse and disturbed liver function test results. On presentation the women were less likely to be suspected of alcohol abuse (9; 38%) than the men (59; 77%). Although the quantity of alcohol consumed and length of history of alcohol abuse were similar for men and women, the incidence of chronic advanced liver disease was higher among women (86%) than among men (65%). Women, however, were less likely to have developed primary liver cell cancer. Overall the women had a higher incidence of other alcohol-related disorders and were less likely to stop abusing alcohol (2; 9%) than were their male counterparts (22; 29%). Women seem to be more susceptible to alcohol-related disease.


Disseminated histoplasmosis in an English patient with diabetes mellitus.

Histoplasma capsulatum is not endemic in Britain. We report a case of disseminated histoplasmosis in an English man who had not ventured out of northern Europe for 30 years. The disease presented as painful mouth ulcers and hepatosplenomegaly six months after he had developed maturity-onset diabetes. The origin of the infecting fungus may have been from within the United Kingdom or alternatively it may have existed as an intraoral saprophyte for over 30 years.


Thalamic projections to parietal cortex.

Thalamic projections to parietal regions of cerebral cortex were investigated in the cat by retrograde degeneration and retrograde transport techniques. Studies of retrograde cellular changes indicate cortically projecting cells in the lateroporterior nucleus (LP), rostral pulvinar (Pul), and the ventral part of the laterodorsal nucleus (LD). When lesions were placed in the cortex of young kittens, clear chromatolytic changes and cell loss were also consistently observed in middle and caudal parts of the ventroanterior nucleus (VA). Investigations of retrograde transport following intracortical injections of horseradish peroxidase have confirmed the results of retrograde degeneration studies by demonstrating cortically projecting cells in VA, LP, LD, and Pul. Retrograde transport studies also indicate cortically projecting cells in the central lateral nucleus. Material from both experimental techniques demonstrates a loose topographic organization of the projections from the lateral thalamus. Anterior parts of LP project to the anterior lateral gyrus and anterior middle suprasylvian gyrus. Middle LP and rostral Pul project to the middle suprasylvian gyrus.


Visual wulst influences on the optic tectum of the pigeon.

The influence of the visual wulst on the optic tectum of Columba livia were studied. Analysis of the surface field potential evoked by optic nerve stimulation showed that it is composed of two presynaptic waves (pr1 and pr2) a negative monosynaptic wave (N) and a late, positive component (P) due to activation of deeply located neurons. Single shock visual wulst stimulation elicited a surface-positive field potential the depth profile of which showed that it is due to the activation of neurons of the deep tectal layers, probably different from those responsible for the P wave. Visual wulst stimulation depresses the positive component of the field potential elicited by optic nerve stimulation. It is suggested that this effect is mediated by intratectal inhibitory interneurons.


Convergence of excitatory synaptic inputs to caudate spiny neurons.

Intracellular recordings were obtained from cat caudate nucleus neurons. These cells responded with convergent, monosynaptic EPSPs to cerebral cortex, intralaminar thalamus, and substantia nigra stimulation. Intracellular injection of horseradish peroxidase into these electrophysiologically defined neurons shows that they represent the spiny neuron of the caudate based upon somadendritic morphology. The axons of these cells are appreciably longer than previous reports indicate. Several lines of evidence are discussed to question the intrinsic nature of these neurons.


Influence of voluntary movement and posture on recurrent inhibition in human subjects.

Recurrent inhibition elicited by a conditioning H reflex is measured in normal man by the amount of inhibition of a test H reflex produced by motoneurones that have already given rise to the conditioning reflex. The recurrent inhibition of soleus motoneurones is lowered during a voluntary contraction of this muscle while it is enhanced during a voluntary contraction of its antagonist, the tibialis anterior, and not modified during a contraction of the quadriceps. This recurrent inhibition is also enhanced when the subject is standing without support. These changes in recurrent inhibition are thought to imply supraspinal mechanisms acting on Renshaw cells. The functional significance of these changes is discussed in relation to the recent finding in animals of recurrent depression of the transmission in the Ia inhibitory pathway.


Distribution of endorphins (peptides with morphine-like pharmacological activity) in pituitary.

Endorphin was found in the pituitary gland of rat, sheep, pig, cow and man. In bovine pituitary, highest concentrations have been found in that part of the posterior lobe containing the pars intermedia, although endorphin was also present in the pars distalis. Analysis by gel filtration and adsorption chromatography suggested that the major endorphins from rat, pig and cow pituitary were similar, with apparent molecular weights in the range 3000-3500 daltons.


Quantitative autoradiographic analysis of the time course of proliferation of contralateral entorhinal efferents in the dentate gyrus denervated by ipsilateral entorhinal lesions.

The time course of the post-lesion proliferation of contralateral entorhinal afferents which occurs in response to ipsilateral entorhinal lesions was quanititatively analyzed with autoradiographic techniques. The extent of the crossed projection to the dentate granule cells was quantified on the basis of a contralateral/ipsilateral (C/I) ratio of grain density in the entorhinal terminal zones at 6, 8, 10, 12, 14, and over 60 days post-lesion. C/I ratios of grain density indicate little if any change in the crossed projection at 6 days post-lesion. Between 8 and 12 days post-lesion, the extent of the crossed projection increases dramatically, on the basis of the C/I ratio of grain density. C/I ratios do not increase further between 12 and 14 days post-lesion, but are higher at 60 days post-lesion. These results suggest that the crossed pathway proliferates extensively within the denervated zones between 8 and 12 days post-lesion, and may continue to proliferate at a much slower rate after 12 days post-lesion.


Dissociation of hippocampal EEG from its behavioral correlates by septal and hippocampal electrical stimulation.

(1) Electrical stimulation of septum or hippocampus produced frequency specific hippocampal synchrony and hippocampal desynchrony. (2) Behaviors normally correlated with the occurrence of hippocampal desynchrony continued during elicitation of synchrony. Similarly, behaviors normally correlated with the occurrence of synchrony continued during elicitation of desynchrony. Stated conversely, specific hippocampal patterns were elicited without eliciting the behaviors which occur when similar patterns are generated by the spontaneously behaving animal. (3) These results suggest that the import of hippocampal patterns highly correlated with specific types of behaviors might best be sought in processes remote from the endpoint of motor performance per se.


The mechanical properties of human motor units with special reference to their fatiguability and recruitment threshold.

The recruitment thresholds, twitch tension, twitch contraction time and fatiguability of human motor units have been studied in the first dorsal interosseous of the hand. Units recruited at contraction strengths less than 50 g had relatively low twitch tensions (0.18-1.9 g), long contraction times (59-146 msec) and were non-fatiguable. Units recruited at higher contraction strengths (less than 200 g) had higher twitch tensions (15-26g), faster contraction times (33-57 msec) and were highly fatiguable. It is concluded that during graded voluntary muscle contractions motor units are recruited in order of increasing contraction strength and diminishing fatigue resistance.


The path and rate of growth of regenerating motor neurons in the cockroach.

Nerve root 5 that supplies the coxal depressor muscles from the metathoracic ganglion in the cockroach was crushed. Regeneration of the motor neurons was studied by cutting the nerve at several distances from the crush point and introducing cobalt chloride into the cut end. The operation was followed by a lag period of about 13 days after which the axons regenerated at a rate of 0.9 mm per day. After regeneration had been completed a pattern of axon distribution was established among the nerve branches that was very similar to that found in intact, normal cockroaches. This pattern was established through an apparent directed growth of certain axons from identified cells into branch 5rl, their normal pathway. However, at the same time, radom or increased branching of other unidentified motor neurons produced some errors in the distribution of axons among the nerve branches. Eventually these errors were corrected by the degeneration of neuronal processes that did not synapse with correct target muscles. These results demonstrate the requirement for a highly specific intercellular recognition process between individual, identified motor neurons and the appropriate muscles they innervate in order to reform the original innervation pattern during regneration.


Selective loss of lateral geniculate cells in the adult cat after chronic monocular paralysis.

Adult cats with chronic (two weeks) monocular paralysis had lateral geniculates with diminished numbers of cells characterized by long latency responses to optic chiasm shock. This diminution was unexpectedly more prominent among lamina A1 cells, driven by the mobile and presumably normal eye, than among cells receiving inputs from the paralyzed eye. These results confirm reports suggesting that a hitherto unrecognized degree of plasticity exists in the central nervous system of the adult cat.


Neural mechanisms of the corneal blinking reflex in cats.

Neural mechanisms of the blinking reflex elicited by corneal stimulation were analyzed with electrophysiological techniques in the encéphale isolé cat. (1) Mechanical and electrical stimulation elicited two successive responses of the electromyogram of the orbicularis oculi. Neuromuscular unit studies revealed that the same unit was excited twice and that the latencies of both responses corresponded well with the two EMG responses. (2) The late response was easily affected by anoxia and pentobarbital administration, and was also abolished with the slow-wave sleep stage. (3) Both responses were abolished by ipsilateral transection between the inferior colliculus and genu of the facial nerve. (4) Compared with the latencies of the EMG, the sum of the conduction times through the sensory trigeminal nucleus and the facial nucleus corresponded with the latency of the early response. The sum of the conduction times through the reticular formation, added to the former reflex arc, corresponded to the latency of the late response. (5) The reflex pathway of the early response is consistent with a three-neuron arc passing through the sensory trigeminal nucleus and the facial nucleus. The late response may employ a multisynaptic arc passing through the brain stem medial reticular formation between the sensory trigeminal nucleus and the facial nucleus.


Noradrenaline distribution insubcortical areas of the human brain.

Spectrofluorimetric assay of noradrenaline (NA) was performed in human postmortem brain material in an attempt to provide a detailed map of the subcortical distribution pattern of NA in the human brain. The concentrations of NA was particularly high in 4 areas of the lower brain stem: the area postrema, the area of the nuclei paranigralis-parabrachialis pigmetosus, the locus coeruleus, and the interpeduncular nucleus. The NA-rich areas of the forebrain were determined to be the hypothalamus, the central amygdaloid nucleus, the nucleus accumbens septi, the medial part of the olfactory area, and the bed nucleus of the straia terminalis. The biochemical mapping of NA is discussed in relation to distribution studies based on the histofluorescence technique.


Metabolism of monoterpene alcohol, linalool, by a soil pseudomonad.

A microorganism of the genus Pseudomonas has been isolated from the soil by enrichment culture techniques with linalool(I) as the sole source of carbon and energy. The organism is also capable of utilizing limonene, citronellol, and geraniol as substrates but fails to grow on citral, critranellal, and 1,8-cineole. Fermentation of linalool by this bacterium in a mineral salt medium results in the formation of 10-hydroxylinalool(II), oleuropeic acid (IX), 2-vinyl-2-methyl-5-hydroxyisopropyl-tetraphydrofuran)linalool oxide, V), 2-vinyl-2-methyl-tetrahydrofuran-5-one(unsaturated lactone, VI), and few unidentified minor metabolities. Probable pathways for the biodegradation of linalool are presented.