[14C]palmitate uptake in isolated rat liver mitochondria: effects of fasting, diabetes mellitus, and inhibitors of carnitine acyltransferase. The rapid association of Na-[16-(14)C]palmitate with isolated rat liver mitochondria was measured by an oil separation method. This association was time and temperature-dependent and was absolutely dependent on the presence of exogenous ATP and CoASH and partially dependent on exogenous carnitine. Carnitine dependence was enhanced at lower concentrations of [(14)C]palmitate. At 6.5 micro M [(14)C]palmitate (molar ratio of palmitate to albumin equal to 0.54), the rate of association was linear for 20 sec and was increased more than 100% in the presence of carnitine. Carnitine-dependent association was inhibited by 2-bromopalmitate, an inhibitor of carnitine acyltransferase I, but not by (+)-octanoylcarnitine, a presumed inhibitor of carnitine acyltransferase II. The association of [(14)C]palmitate with mitochondria was enhanced from 190 to 330% in mitochondria isolated from fasted animals and from 160 to 230% in mitochondria isolated from diabetic, ketotic animals as compared to control animals. The enhanced association with mitochondria from fasted animals was inhibited by 2-bromopalmitate. These studies demonstrate a method of evaluating fatty acid association with mitochondria which, because of its dependence on carnitine and carnitine acyltransferase I activity, most likely represents true uptake into mitochondria. Furthermore, these studies indicate that the carnitine-dependent uptake of fatty acids into mitochondria is enhanced in the two ketotic states evaluated and that the carnitine acyltransferase system may be a regulatory site in ketone body production.


Virulence of Mycobacterium tuberculosis and susceptibility to peroxidative killing systems. At sub-bactericidal concentrations of hydrogen peroxide, Mycobacterium tuberculosis was killed by hydrogen peroxide/peroxidase/halide microbicidal systems. The halide cofactor could be either iodide or, with much lower efficiency, chloride. Omission of any one of the reactants eliminated the tuberculocidal effect. Differences in susceptibility between different strains of M. tuberculosis did not correlate with virulence differences. The observations are discussed in the context of host defence mechanisms against tuberculosis.


R plasmids which alter ultraviolet light-sensitivity and enhance ultraviolet light-induced mutability in Pseudomonas aeruginosa. R plasmids pMG1, R2, R931 and pMG15 increased the survival of Pseudomonas aeruginosa exposed to ultraviolet radiation (u.v.) in the wild type, and uvr and polA mutants but did not alter the u.v.-response of a recA mutant. The R plasmid RPL11 reduced u.v.-survival in the wild type, and uvr and polA mutants but did not alter the u.v.-response of a recA host. All the plasmids enhanced the level of spontaneous and u.v.-induced back mutation (Trp+) in a trpB1 strain. The effect of sublethal concentration of sodium arsenite following u.v.-irradiation was examined. It was concluded that in strains trpB1(pMG1) and trpB1(R931), u.v.-protection is determined by a recA+-dependent, arsenite-sensitive repair pathway, whereas in strains trpB1(R2) and trpB1(pMG15), u.v.-protection is determined by a recA+-dependent, arsenite-insensitive step in DNA repair.


Interferon inducing activity of polyinosinic acid. Although poly(I) is generally considered to be inactive as an interferon inducer, we have found several authentic poly(I) preparations to be effective inducers. Their interferon inducing ability varied considerably from one cell system to another. In human diploid fibroblasts, primed with interferon and superinduced by cycloheximide and actinomycin D, all active poly(I) samples proved nearly as effective in inducing interferon as poly(I).poly(C). In primary rabbit kidney cell cultures, the active poly(I) samples were either as active, or 3 to 30 times less active than poly(I).poly(C). In intact rabbits they were 100 times less active than poly(I).poly(C). Except for one particular sample, all active poly(I) preparations were inferior to poly(I).poly(C) when assayed for interferon induction in interferon-treated mouse L cells; in DEAE-dextran-treated L cells, they induced little, if any, interferon. The poly(I) inducers of interferon were considerably more susceptible to degradation by TI ribonuclease, pancreatic ribonuclease and human serum nuclease(s) than was poly(I).poly(C) when assayed under the same conditions. Due to their limited half-life time in biological fluids, poly(I) analogues such as those described here may offer a greater safety margin in clinical use than poly(I).poly(C).


Natural distribution of squirrel monkey retrovirus proviral sequences in primate DNAs. 3H-labelled 70S RNA of squirrel monkey retrovirus (SMRV) hybridized to a high degree (greater than 52%) to the DNA of various tissues of two squirrel monkeys. Hybridization of the same probe to DNAs of other primates including New World monkeys (Woolly monkey, capuchin, owl monkey), Old World monkeys (rhesus, African green), apes (gibbon, chimpanzee), and human (A204 cells infected with MPMV) revealed no significant hybridization. Analysis of the kinetics of hybridization indicated that SMRV provirus was present in multiple copies in various squirrel monkey tissues (C0t 1/2 = 120 to 400) and in SMRV-infected A204 cells at a low number of copies (C0t 1/2 = 1500). These results demonstrate that SMRV is an endogenous virus of squirrel monkeys and the first isolated from a New World monkey.


Electron microscopic observation of African swine fever virus development in Vero cells. African swine fever virus emerges from infected Vero cells either from areas of smooth cell surface or from microvilli. The two patterns may occur at different sites on the same cell and are unique for this virus. The scanning electron micrographs supplement regular thin section views.


Monitoring inpatient length of stay in a community mental health center. The authors assess their experience with reviewing the length of stay of inpatients in a mental health facility. The study yielded data that refine the review process and suggest a rationale for selection of cases for review that may have educational value both to the admitting staff and physician-reviewers. The authors urge experimentation with length of stay norms which reflect specified treatment protocols related to diagnosis, rather than reliance on diagnosis alone.


The effect of beta-alanine on motor behaviour, body temperature and cerebral monoamine metabolism in rat. Intracerebroventricular (ICV) injection of beta-alanine produced a decrease in rectal temperature, inhibition of exploratory behaviour and motility, and changes in the metabolism of cerebral monoamines. Dopa and 5-HTP accumulation after inhibition of L-aromatic amino acid decarboxylase, NSD 1015 (3-hydroxybencylhydrazine HCl, 100 mg/kg i.p.) was found to be significantly increased in all the dissected cerebral regions of animals treated with beta-alanine, as compared to the controls. Levels of tyrosine and tryptophan did not show any significant change. Endogenous levels of dopamine (DA), noradrenaline (NA), serotonin (5-HT) and 5-hydroxyindolacetic acid (5-HIAA), did not change. After inhibition of the catecholamines synthesis with alpha-methyltryrosine (alpha-MT), dopamine depletion was retarded and noradrenaline accelerated, but without reaching statistical significance. After intraperitoneal (i.p.) injection of beta-alanine, significant changes in motor behaviour were found. Body temperature and metabolism of brain catecholamine were unchanged. This lack of effect could be explained by poor penetration through the blood-brain barrier.


Immunological abnormalities and HLA antigen frequencies in IgA deficient patients with epilepsy. Twenty-three epileptics with constitutional factors for seizures and low IgA serum concentrations were studied. Imbalance of the IgG subclasses was often observed, the IgG4 being undetectable in 13 (65%) patients. The percentage of circulating lymphocytes positive for surface immunoglobulins was normal except for slightly increased values for IgA in six (28.5%) patients. Of the epileptics, 48% showed subnormal proportions of lymphocytes forming spontaneous rosettes. There was a distinct trend for HLA-A2 antigen in the patients tested.


Profound hypoxia in Papio anubis and Macaca mulatta--physiological and neuropathological effects. I. Abrupt exposure following normoxia. II. Abrupt exposure following moderate hypoxia. Lightly anaesthetized and spontaneously breathing P. anubis (PA) and M. mulatta (MM) inhaled at ambient pressure 3.2% oxygen (identical to 37,500 ft or 11,430 m) from air and also after pre-exposure to 14% oxygen (identical to 10,000 ft or 3,048 m). The EEG, ECG, respiratory rate, arterial and cerebral venous sinus pressures, end-tidal pO2 and pCO2 and body temperature were recorded. Arterial and cerebral venous sinus blood gases, pH and pyruvate and lactate contents were estimated. Before hypoxia, MM showed a relative hyperventilation. Profound hypoxia, from air, ended with the "last breath" at 89--205 sec in PA and at 93--570 sec in MM. Brain damage was restricted to one MM (4 exposures). Profound hypoxia after exposure to 14% oxygen ended with the "last breath" at 87--210 sec in PA and at 120 sec--94 min (including 9 exposures over 5 min) in MM. Brain damage was restricted to one MM ("last breath" at 94 min). In the two MM with brain damage there was evidence of reduction in cerebral perfusion near the end of profound hypoxia. Brain damage in one animal contrasts with the frequent and often severe brain damage in MM after equivalent sub-atmospheric decompressions preceded by exposure to moderate altitude (10,000 ft).


Reversibility of ischaemically induced changes in extracellular potassium in primate cortex. Following the massive increase in extracellular potassium activity that occurs in cerebral cortex when local blood flow falls below 8--11 ml/100 g/min, recovery of potassium toward normal levels might be expected when flow is restored. This study assessed the reversibility of such potassium increases, produced by middle cerebral artery occlusion in 13 baboons anaesthetised with alpha-chloralose, in relation to a wide range of ischaemic duration and density and post-occlusion flow. Potassium was measured with ion-exchanger microelectrodes and flow by hydrogen clearance. The artery was occluded for 136 +/- 63 min (mean +/- SD) and measurements were continued thereafter for 93 +/- 57 min without systemic hypertension. Upon reperfusion, partial or complete recovery (i.e., to within control confidence limits) of potassium was seen in all animals, but the rate of recovery varied widely and potassium clearance showed bi-compartmental characteristics in 7 animals. The fast component (or initial slope) rate constant was significantly correlated with post-occlusion flow and (inversely) with the duration of occlusion for which flow fell below the arbitrary threshold of 10 ml/100 g/min (the flow deficit). The slow component was unrelated to these quantities. Complete recovery was associated with a significantly higher post-occlusion flow, and smaller flow deficit, than was partial recovery. Secondary increases in potassium, associated with relatively high flow deficits and post-occlusion flows, were seen in 5 animals. These results are discussed in terms of factors that may determine potassium clearance and the possibility that elevated levels of potassium (demonstrated here to be prolonged well into the post-occlusion phase) might influence the evolution of a cortical infarct.


An electron-microscopic analysis of axonal alterations following blunt contusion of the spinal cord of the rhesus monkey (Macaca mulatta). Following contusion (500 g-cm) at upper thoracic levels, sections from the spinal cords of 13 rhesus monkeys were examined with the electron microscope. Survival times ranged from 4 hr to 10 weeks. Samples were taken from the lesion site, from areas 3 and 10 mm rostral and caudal to the lesion center, and from the lumbosacral cord. Four hours postoperatively, several small axons located close to the grey matter at the lesion site exhibit abnormal accumulations of organelles including mitochondria, dense bodies, vesicular structures, and multivesicular bodies. By 12 hr postoperatively many axons at the lesion site appear to be swollen with organelles and exhibit thinning of their myelin sheath. Some organelle-rich profiles lack a myelin sheath altogether. At this time dark axons are present, and myelin sheaths which appear to be empty or to contain small amounts of flocculent material. By 18 hr the first signs of axonal changes appear in the tissue taken 3 mm from the center of the lesion, both swollen and pyknotic axons being present. The axonal pathology spreads from the central part of the cord to the periphery at the impact site, and from the impact site rostrally and caudally, beginning at 18 hr and continuing for the duration of the study. Small fibers degenerate first and large fibers later. The axonal changes observed appear to be comparable to those reported for the central and peripheral nervous systems in other species.


The paratrigeminal nucleus. I. Neurons and synaptic organization. The paratrigeminal nucleus, a diffuse collection of neurons on the lateral medullary surface, lies embedded in the fibres of the restiform body, ascending spinocerebellar tract and the spinal tract of the trigeminal nerve. Its rostrocaudal extent is approximately 1500--2000 micrometer in the rat, 2800--3500 micrometer in the rhesus monkey, and 5000--6000 micrometer in the human, where it is a well-defined nucleus. In Golgi preparations the neuronal somata are generally fusiform, ranging from 8--15 micrometer in width and 15--25 micrometer in length. Electron microscope studies show that their polar dendritic processes are thick and long and they intertwine in bundles among islands of cells or myelinated fibres. The perikarya have a high nucleus to cytoplasm ratio and the scanty cytoplasm is conspicuous for its paucity of organelles and its plethora of polysomal arrays. The neuropil is complex and contains a heterogeneous population of axonal varicosities displaying markedly different axoplasmic structures. Many different types of large granular vesicle-containing axons prevail. These axons engage in axo--somatic, axo--dendritic, axo--spinous and axo--axonic synapses with the processes of the cells within the nucleus.


The paratrigeminal nucleus. II. Identification and inter-relations of catecholamine axons, indoleamine axons, and substance P immunoreactive cells in the neuropil. The localization of three different putative neurotransmitters -- indoleamine, catecholamine, and Substance P -- was studied in the paratrigeminal nucleus of the rat and rhesus monkey at the light and electron microscope level by autoradiography following administration of [3H]5-hydroxytryptamine, or [3H]norepinephrine, and by immunocytochemistry using the unlabelled anti-Substance P antiserum peroxidase--antiperoxidase technique. The paratrigeminal neurons are not monoaminergic but certain cells exhibit Substance P-like immunoreactivity. These cells receive a rich plexus of indoleamine afferents, a sparse catecholamine input, and a rich plexus of fibres with Substance P-like immunoreactivity. Of the entire monoaminergic population of labelled axons, more than 60% are synaptic and less then 40% nonsynaptic, and this proportion is the same for indoleamines as for catecholamines. Indoleamine axons form a heterogeneous population with at least four different morphological types that are synaptic and three that are nonsynaptic. They bear distinctive collections of small, clear, tubular or large granular vesicles, which distinguish one category of axon from another. These axons engage in numerous axo--somatic, axo--spinous, axo--dendritic, and possibly axo--axonic relations with paratrigeminal neurons. The catecholamine axons are also heterogeneous in axoplasmic morphology but their terminal contacts are distributed to more peripheral portions of dendrites. The significance of the inter-relations between the monaminergic and peptidergic elements in the paratrigeminal nucleus is discussed in relation to the possible functions of this nucleus as a nociceptive, chemosensitive, or pressure-sensitive centre on the lateral medullary surface.


Radioautographic study of 5-hydroxytryptamine-containing nerve terminals in central ganglia of Planorbis corneus: comparison with other species and characteristics of the serotoninergic nerve terminal. Central ganglia from Planorbis corneus were incubated with [3H]5-hydroxytryptamine and [3H]-leucine. After fixation, sections were examined by light and electron microscopic autoradiography. With [3H]5-hydroxytryptamine there was a high level of uptake into a small number of axons and terminal processes in the neuropil. The terminal processes contained granular vesicles (diameter 50--120 nm), some of which possessed eccentrically placed cores, and agranular vesicles (mean diameter 60 nm). No membrane synaptic specializations were observed. With [3H]leucine there was a general distribution of radioactivity throughout the ganglia. The vesicular inclusions and non-specialized nature of the labelled terminal processes were very similar to presumed 5-hydroxytryptamine-containing terminals in other invertebrates and in the mammalian brain. It appears that several anatomical features of serotoninergic nerve terminals are common in all animals studied, although there is no specific characteristic which allows positive identification.


Catabolism and protein binding of Tc-99m pyridoxylideneglutamate. Various Tc-99m-labeled compounds have been suggested as replacements for [I-131] rose bengal for imaging of the hepatobiliary system. Among such compounds are Schiff's bases, which are tin-free Tc-chelates easily prepared by 30-min autoclaving of an equimolar mixture of pyridoxal and an amino acid at pH 8.5. We have compared the properties of several Schiff's bases, including Tc-99m pyridoxylideneglutamate (Tc PyG) with [I-131] rose bengal. Under conditions described, Tc-PyG can be prepared free of Tc-pyridoxal and with less than 2% TcO4- radiochemical impurity. Blood clearance and biliary excretion were studied in three animal models, and in normal human volunteers. In all animal models, Tc-PyG initially cleared from the blood more rapidly than rose bengal, but a significant amount of Tc-PyG was excreted in the urine, this in contrast to [I-131] rose bengal which was almost completely excreted through the biliary system. Species differences were observed in the degree of urinary versus biliary clearance of Tc-PyG, with significantly greater urinary excretion in dogs than in monkeys and rabbits. Replacing glutamate with other amino acids did not significantly increase the blood clearance rate or decrease urinary excretion, so that Tc-PyG appears to be at least as good as any of the others studied. Tc-PyG was only 20% bound to plasma proteins, and electrophoretic and chromatographic studies did not reveal any in vivo changes of Tc-PyG before excretion in urine or bile.


Effect of low-protein diets on free amino acids in plasma of young men: effect of protein quality with maintenance or excess energy intake. Hematological changes due to protein deprivation were studied in 34 young Japanese men who were given a standard diet with an N intake of 200mg/kg for one week and then low-protein diets with maintenance (45 +/- 2 kcal/kg) or excess (57 +/- 2 kcal/kg) energy and N intakes of about 44 to 99 mg/kg of whole egg or about 50 to 121 mg/kg of polished rice for three weeks. In the period of the low-protein diet the concentrations of most individual free plasma essential amino acids (EAA) decreased significantly in general, and thus the total EAA concentration decreased significantly. Lowering of the valine concentration and elevation of the alanine concentration were the highest changes. The total nonessential amino acid (NEAA) concentration increased significantly in men fed a low-rice-protein diet, but not in those fed a low-egg-protein diet. Consequently, in the former group the ratio of essential to nonessential amino acids fell significanly from 0.96 in the control period to 0.61--0.74 in the period of consuming the low-protein diet. The effect of protein deprivation on the plasma EAA concentration was also larger with egg protein than with rice protein, and the total EAA concentration of men fed egg protein changed significantly and in parallel with the N intake over the range of 44 to 99mg/kg. The decreases in serine and threonine and increase in alanine tended to be more when energy intake was over the maintenance level. The concentration of plasma proteins and especially albumin decreased significantly during the period of consuming the low-protein diet. The interrelation of plasma-free amino acids, the amino acid pool in tissures and dietary N and energy intakes is briefly discussed.


A fine structural comparison of the healing of incisional wounds of mucosa and skin. Incisional wounds of the same length and depth were made on tongue and dorsal skin of rats and the fine structural aspects of the responses of these were compared. Comparisons were made between the timing and degree of phagocytosis, the timing and rate of epithelial cell migration, of overall rate of healing, and of reformation of basal lamina and attachment complex in these two tissues. Phagocytic activity in epithelium and connective tissue of mucosa reached higher levels than in skin and the peak of activity in the epithelium of the mucosa was earlier than in the epidermis. Mononuclear phagocytes were active in phagocytosis, neutrophils showed little phagocytic activity. Epithelial migration was found to begin earlier in mucosa than in skin. Epithelialization of the wound and repair of supporting tissue were completed earlier. The same sequence in the renewal of ultrastructural components of the hemidesmosome-attachment complex was found in skin and mucosa, but was completed earlier at the mucosal site. Mechanical and physical as well as physiologic factors may play a role in determining the differing rates of repair in mucosa and skin.


Odontoblast metabolism in rats deficient in vitamin D and calcium. III. Protein synthesis in vitro. Dentinogenically active rat incisor odontoblasts were dissected out from animals fed a low calcium, vitamin D free diet (R 25). Protein synthesis by these cells was studied by means of short-time incubation in an in vitro system in the presence of the radioactive labeled precursors L-leucine, L-fucose and L-proline. A significantly increased leucine and proline incorporation into the protein synthesized was noted in the cells from rats fed the deficient R 25 diet compared with odontoblasts from rats fed an adequate control diet (R 47). No difference between the two groups was found when fucose was utilized as a precursor. The well known increase in predentin width when feeding a rachitogenic diet may thus be explained by an increase in organic matrix synthesis in addition to the possible negative direct effects of lowered serum Ca content. Prior to this study, the behavior of proline as a precursor in the in vitro system was studied. The possibility of separating leucine-labeled proteins synthesized in the in vitro system by means of SDS-polyacrylamide gel electrophoresis was also shown.


IQ following treatment of lead poisoning: a patient-sibling comparison. Forty-seven children treated for lead poisoning (PbB 50 to 365 microgram/dl) were compared to siblings next in age (PbB less than 40 microgram/dl) by a battery of psychologic tests. Symptoms were present in 18 but none had frank encephalopathy. Physical and neurologic examinations revealed no residual damage. Mean psychologic test scores showed no significant difference between patients and controls except in the arithmetic subtest, in which patients' scores were not related to lead concentration. Intelligence tests failed to distinguish children successfully treated from their sibling controls.


Fluorometric assay for measuring biological half-life of coralyne sulfoacetate in dogs and monkeys. A spectrophotofluorometric assay for coralyne sulfoacetate was developed. Caralyne was extracted from serum samples with n-butyl alcohol, and the drug concentrations were determined fluorometrically at 475 nm when the extract was excited at 325 nm. A biphasic serum decay curve for coralyne was observed for both dogs and monkeys. The biological half-lives for the two phases were 20 and 196 min in dogs and 15 and 142 min in monkeys.


Quantification of the morphological reaction of platelets to aggregating agents and of its reversal by aggregation inhibitors. 1. In rabbit citrated platelet-rich plasma, the changes in shape of the platelets produced by adenosine diphosphate (ADP) or 5-hydroxytryptamine (5-HT) were observed by photometric and volumetric techniques and by measurements of platelet images on electron micrographs either directly or with an image analysing computer. This permitted the indirect manifestations of the shape changes to be correlated with the morphological features responsible for them, i.e. transformation of disks to more spherical forms and extrusion of blebs and spikes. 2. Following the addition of ADP, an initial brief peak in the light scattering records was associated with marked but transient irregularities in the surface of the platelets. These effects were absent when the other shape changes were produced by 5-HT. 3. When the optical manifestations of the shape changes induced by ADP were reversed by the addition of antagonists adenosine triphosphate, 2-chloroadenosine or prostaglandin E1, the morphological changes were reversed by a diminution in the number of spikes and the conversion of spherical platelet bodies to a more discoid form. 4. The volume of extracellular plasma trapped between platelets sedimented by centrifugation was proportional to the number of spikes which they extruded. Under all conditions, the volume of the platelets themselves remained remarkably constant at approximately 5 X 10(-9) microliter./platelet. 5. Addition of a calcium chelating agent alone produced a rapid persistent alteration in the optical properties of platelet-rich plasma. The magnitude of this alteration was proportional to chelator concentration but greater in some plasmas than in others. Similar optical effects were produced when the calcium concentration of platelet-rich plasma was increased by adding calcium. The optical effects produced by calcium or its chelators were unusual in that the changes in transmitted and horizontally scattered light were in opposite directions (transmitted light decreased, scattered light increased) whereas, in all other circumstances so far examined, these changes were in the same direction. The chelators caused the formation of spikes on the platelets without appreciably altering their disk shape, which may explain the unusual nature of the optical effects.


Extrajunctional acetylcholine sensitivity of inactive muscle fibres in the baboon during prolonged nerve pressure block. 1. Nerve-evoked muscular activity was abolished in the small hand muscles of the baboon for 1-2 months by a 3 hr period of nerve compression from a pneumatic tourniquet inflated round the forearm. In the large diameter nerve fibres, this produced either a prolonged conduction block due to local myelin damage at the site of compression, or (in 10-30% of the large fibres) Wallerian degeneration. 2. At varying intervals after nerve compression the extrajunctional acetylcholine (ACh)-sensitivity of innervated but inactive muscle fibres in the fourth lumbrical muscle was measured. Observations were also made on lumbrical muscle fibres at similar intervals after surgical denervation. 3. The ACh sensitivity of nerve-blocked muscle fibres started to develop later than in denervated muscle fibres (10 vs. 7 days) and remained at a lower level (40-80 mV/nC, median ACh-sensitivity) than that of denervated muscle fibres (200-437 mV/nC) from 21 to 63 days after nerve block or denervation. 4. In stimulation experiments on four muscles, extrajunctional ACh-sensitivity of both denervated and innervated but inactive fourth lumbrical muscle fibres was reduced by muscular activity. 5. In four animals mild compression was used in the lower limb to produce persistent nerve block without Wallerian degeneration. With one exception (in which some Wallerian degeneration had occurred) recording with a co-axial needle from abductor hallucis showed no spontaneous fibrillation up to 28 days after compression, although the extrajunctional ACh-sensitivity of the muscle fibres appeared to reach levels similar to those observed in the forelimb. All four muscles developed a slight increase in insertion activity after 1-2 weeks. 6. It may be concluded that both muscular activity and some other neural influence, independent of muscular activity, are able to influence extrajunctional muscle properties in the baboon. The neural influence appears to be more effective in preventing spontaneous fibrillation than in preventing a rise in ACh sensitivity of the extrajunctional muscle membrane.


Studies of growth and development of gametocytes in Haemoproteus columbae Kruse. As determined by their ability to exflagellate and round up, it took the macrogametocyte and the microgametocyte of Haemoproteus columbae in pigeons 68 and 116 h, respectively, after patency to reach maturity. Pigment granules appeared in the undifferentiated gametocytes 8 h after invasion of blood. Vacuoles were observed in young gametocytes and persisted in the older forms. The growth curve of H. columbae is close to the sigmoidal curve for growth in protozoa. Multiple infection was noticed in pigeons with high levels of parasitemia, but no more than 2 gametocytes reached maturity; such multiple infections were rare in relapses. The sex ratio of the gametocytes was 1:1. Strong lateral displacement of the nuclei of infected erythrocytes was the rule; hypertrophy was negligible.


Characteristics of the purified uteroglobin-like protein from rabbit lung. A uteroglobin-like protein was prepared from lung extracts of female rabbits by absorption to immobilized anti-uteroglobin immunoglobulin and purified to homogeneity by gel filtration on Sephacryl S-200. The final preparation is indistinguishable from uteroglobin according to its behaviour in Ouchterlony double-diffusion, polyacrylamide gel electrophoresis under denaturing and non-denaturing conditions, ultraviolet spectrum, tryptic peptide analysis, and progesterone-binding properties. Progesterone binding to the lung protein exhibits an affinity similar to that observed with authentic uteroglobin and is equally enhanced by reduction of the protein with dithiothreitol. Competition experiments with non-radioactive steroids demonstrate a similar steroid-specificity for both proteins. Progesterone binding causes a perturbation in the ultraviolet absorbance of tyrosine residues of the lung protein similar to that observed with uteroglobin. These data suggest that the proteins prepared from both sources are biochemically identical.


Nalorphine-like properties of some 2,3-dimethyl-3-arylpiperidines. A number of N-substituted 2,3-dimethyl-3-arylpiperidines having an m- or p-arylhydroxyl were prepared and evaluated for analgesic agonist and antagonist properties. The diastereomeric N-allyl and N-cyclopropylmethyl derivatives behaved as pure potent antagoinists. Substitution of the arylhydroxyl from the meta to the para position resulted in a net fall of the antagoinist activity.


Diethyl (4baalpha,4calpha,9aalpha,9balpha)-3,6-dichlorocyclobuta[1,2-b:3,4-b']bisbenzofuran-9a,9b(4bH,4cH)-dicarboxylate: the cis,syn photodimer of ethyl 5-chlorobenzofuran-2-carboxylate, an analogue related to the antilipidemic drug clofibrate. The antilipidemic properties of diethyl (4balpha,4calpha,9aalpha,4balpha)-3,6-dichlorocyclobutal[1,2-b:3,4-b']bisbenzofuran-9a,9b(4bH,4cH)-dicarboxylate, herein termed dimer 8, were studied in sucrose-fed and in Triton-induced hyperlipidemic rats. Whereas clofibrate (0.4 mmol/kg) exhibited both anticholesterolemic and antitriglyceridemic activity, dimer 8 showed only antitriglyceridemic properties at the lower dose (0.2 mmol/kg) in sucrose-fed rats. Dimer 8 only lowered serum triglycerides levels in Triton WR-1339 hyperlipidemic rats, whereas clofibrate lowered both cholesterol and triglyceride levels. In the chronic sucrose-fed model, dimer 8 and clofibrate lowered hepatic HMG-CoA reducatase activity and produced significant elevations in several parameters of hepatic drug metabolism. No positive relationship between serum cholesterol lowering and reduction of hepatic HMG-CoA reductase activity was observed by these agents in sucrose-fed rats.


Effect of sodium transport inhibition on active phosphate transport by toad bladder. The relationship between active Na transport (estimated by the short-circuit (SCC)) and active inorganic phosphate (Pi) transport was studied in the toad bladder. When SCC was inhibited by amiloride, ouabain, or removal of K from the serosal bathing solution, active Pi transport was totally inhibited. When Na was replaced isotonically by choline in either the mucosal bathing solution or both the mucosal and serosal bathing solutions, there was no measurable SCC or active Pi transport. These experiments are compatible with the hypothesis that active Pi transport occurs only in the presence of active Na transport.


Restraint-induced inhibition of 7,12-dimethylbenz[a]anthracene-induced mammary tumors: relation to stages of tumor development. Experiments on the use of chronically applied restraint to reduce the number of mammary tumors developing in response to treatment of rats with 7,12-dimethylbenz[a]anthracene indicated that this inhibitory effect was largely due to restraint applied after the induction period; preinduction restraint and induction period restraint had no significant effect on tumor development. After termination of the restraint treatment, the rate at which new tumors appeared first increased and then decreased. Restraint did not affect the proportion of tumors regressing after ovariectomy.


Primary culture of rat mammary epithelial cells. II. Cytotoxic effect and metabolism of 7,12-dimethylbenz[a]anthracene and N-nitroso-N-methylurea. To determine the cytotoxicity of 7,12-dimethylbenz[a]anthracene (DMBA) and N-nitroso-N-methylurea (NMU) on primary cultures of rat mammary cells, cultures were exposed to various concentrations of these carcinogens. Cytotoxicity was evident after exposure for 24 hours to as little as 0.1 microgram DMBA/ml. Cytotoxicity was evident after exposure for 2 hours with NMU at concentrations between 80 and 160 microgram/ml. Primary cultures of rat mammary cells were also examined for their ability to metabolize [3H]DMBA into water-soluble products. During a 48-hour period, mammary cells could convert 2.2% [3H]DMBA to water-soluble metabolites. The cells retained (for at least 4 days) small quantities of [3H]DMBA that were insoluble in organic solvents.


Crico-arytenoid joint obliteration following longterm intubation in the premature infant. Twin male premature infants suffering from hyaline membrane disease were intubated with Cole endotracheal tubes. One died at 25 weeks of age of cor pulmonale, still intubated. The other died at 32 weeks, six weeks after tracheotomy. Both larynges were serially sectioned and compared to normal. The crico-arytenoid joints were destroyed by inflammatory granulation tissue, and later obliterated by fibrous tissue. The probable pathogenesis and implications are discussed.


Studies on the function of cell membrane. 11th Report: Binding of cytochrome b5 to liver microsomes and plasma membranes isolated from normal and CCl4-treated rats. Cytochrome b5 was isolated from liver microsomes using a detergent-method. The hemoprotein was found to bind to liver plasma membranes in vitro and was accompanied by an increase in NADH-cytochrome c reductase activity, but not NADH-ferricyanide reductase activity. As in the case of microsomes, the binding to plasma membranes was temperature-dependent and was tight to the extent that the bound cytochrome b5 was little released under high ionic strength. The capacity of plasma membranes for the binding was less than that of microsomes. Administration of CCl4 did not significantly affect the binding of the hemoprotein in both fractions. These results add support to our previous proposal that the elevation of NADH-cytochrome c reductase activity of liver plasma membranes observed early after administration  of CCl4 may be caused by the binding of cytochrome b5 which has probably migrated from the endoplasmic reticulum.


Alterations in spontaneous activity of the isolated frog spinal cord in Calcium-free environment. Spontaneous electrical activity of the isolated frog spinal cord was examined in Ca2+-free environment. Spontaneous discharges from the ventral root altered in four distinguishable steps. The first step was an immediate increase in the rate of spontaneous discharges and the second was a gradual decrease. The third was the occurrence of rhythmical bursts, and the last, the appearance of continuous firing. The rhythmical bursts could be depressed by the addition of metabolic inhibitors (ouabain or dinitrophenol in a concentration of 5 x 10(-5) M) as well as of Ca2+-chelating agents (EDTA or EGTA in a concentration of 10(-3) M). Our results suggest that the occurrence of the rhythmical bursts requires a metabolic pumping process to redistribute Na+ and K+ across the membrane and a small amount of Ca2+ for transmitter secretion.


Polychlorinated dibenzofurans--potent inducers of rat hepatic drug-metabolizing enzymes. The effects of polychlorinated dibenzofurans (PCDFs), trace toxic contaminants of commercial polychlorinated biphenyl preparations (PCBs), on the induction of hepatic drug-metabolizing enzymes were studied in the rat. PCDFs were about a thousand times more potent than PCBs (Kanechlor-500) as inducers of cytochrome P-450. Rats given 10 microgram/kg of PCDFs intraperitoneally for 3 days showed significantly increased hepatic cytochrome P-450 levels. At the highest dose tested, 1000 microgram/kg, a two-fold increase of cytochrome P-450 and a three-fold increase of p-nitroanisole demethylase activity were observed. PCDFs and 3-methylcholanthrene had quite similar effects on microsomal drug-metabolizing enzymes. Both drugs increased p-nitroanisole demethylase activity strikingly and aniline hydroxylase activity moderately, but produced little change in aminopyrine demethylase activity. alpha-Naphthoflavone, which is known to be a specific inhibitor of aryl hydrocarbon hydroxylase induced by polycyclic aromatic hydrocarbons, inhibited at low concentrations p-nitroanisole demethylase activity of rats previously treated with both drugs. Further, both drugs increased the 455 nm to 430 nm peak ratios of ethyl isocyanide difference spectra. Following three daily doses of PCDFs (100 microgram/kg), cytochrome P-450 level and p-nitroanisole demethylase activity remained elevated for over 15 days, with a decrease to control levels after 30 days. Such indicates the slow excretion of PCDFs.


[Pharmacotherapy of peripheral arteriosclerosis]. Peripheral atherosclerosis was treated in 178 patients: 90 were given pyridinol carbamate for 2--4 months, 40 pentoxyphylline, 30 cetedil, and 18 received butalamine. in intermittent claudication pyridinol carbamate and trental proved most effective, cetedil (straten) was less effective. The favourable effect of pyridinol carbamate is associated with its action both on the state of microcirculation and on the content of lipids. A significant decrease in the level of blood triglycerides was observed during treatment with pyridinol carbamate. Pentoxyphylline reduced blood viscosity and platelet aggregation in patients with peripheral atherosclerosis but had no effect on the blood lipid content. Cetedil did not reduce blood viscosity although it decreased the aggregation of erythrocytes and inhibited the second phase of platelet aggregation. The objective criterion for the improvement of circulation in the affected extremities was increased tolerance to load, particularly in medication with pyridinol carbamate and trental.


Diamine oxidase in renal failure.

Diamine oxidase in renal failure. The enzyme, diamine oxidase, is present in many tissues and plays a role in the metabolism of certain amines, some of which may be toxic. In renal failure, plasma diamine oxidase activity was found to be increased in chronically uremic patients and before and after dialysis therapy in patients undergoing maintenance hemodialysis. Diamine oxidase activity was decreased in urine of the chronically uremic patients as compared to normal subjects. In chronically uremic rats, diamine oxidase activity was observed to be increased in plasma and reduced in urine as compared to sham-operated, pair-fed control rats. In the uremic rats diamine oxidase activity was also decreased in kidney and unchanged in liver and muscle. Total amine levels were elevated in plasma and reduced in urine of patients and rats with chronic renal failure. Although the clinical significance of abnormal diamine oxidase activity in renal failure is not clear, it is possible that this enzyme may have a pathophysiologic role in uremia.


Enzyme induction in the uremic liver.

Enzyme induction in the uremic liver. Forty-five days after subtotal nephrectomy or sham-operation of male rats, microsomal enzymes were investigated in vitro. The activities (per milligram) of microsomal protein of two esterases and of two glucuronyltransferases were normal in the uremic rats. The mixed-function oxidation system had lower activities per milligram of protein than that in sham-operated controls. Due to a decrease of the microsomal protein content of the uremic liver, the activities of these enzymes were decreased when calculated for the whole liver. In contrast, the glucoronidation of phenolphthalein remained normal when related to the whole liver, due to an increased activity per mg of protein. Treatment with the plasticizer di-(2-ethylhexyl)-phthalate caused a significant increase of the liver wet weight, the microsomal protein content, and the activity per mg of protein for the demethylation of aminopyrine in subtotally nephrectomized rats but was without influence on the liver of sham-operated controls. It is concluded that uremia itself does not induce liver microsomal enzymes. The microsomal enzymes, however, remain inducible by foreign compounds even under uremic conditions.


Treatment of ectopic calcification in uremia. Nine uremic patients on maintenance hemodialysis who showed wide arterial and/or stable periarticular calcifications in spite of a well controlled hyperphosphatemia were treated with the diphosphonate disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) in doses of 7.5 to 10 mg/kg of body wt/per day for 5 to 9 months. No clinical or biochemical side-effects were noted. A significant reduction of the extent of periarticular calcifications was observed in five patients: two of them had a complete regression of soft-tissue calcifications, and one patient showed a reduction of arterial calcification. EHDP (7.5 to 10 mg/kg of body wt/per day) induced a significant increase of the osteoid volume and osteoid surface without significant modification of the calcification front. No evident effect on bone resorption and on the mineral content of the radius has been observed.


[Case report on "congenital cystic eye" (author's transl)]. The "congenital cystic eye" is a rare ocular malformation due to an arrest of normal development with complete or partial failure in the invagination of the primary optic vesicle between the third and fifth week of embryonic life. A coincidence of maternal varicella infection and congenital cystic eye is described and the possibility of a causal relationship is discussed.


Organization and polysaccharides of sponge aggregation factor. Aggregation factor, the macromolecular complex which mediates species-specific aggregation of dissociated sponge cells, was isolated from several species, partially characterized, and visualized by electron microscopy. All factors were large fibrous complexes with a backbone and side chains or arms. In some factors, the backbone is linear. In others it is circular and the complex appears as a sunburst with arms extending like rays from the circle. The size and location of the polysaccharide chains have been studied using purified preparations of Microciona prolifera. "Sunbursts" treated with ethylenediaminetraacetate (EDTA) for 4 weeks at 0 degrees C dissociate into 3 protein- and polysaccharide-containing components. Sodium dodecyl sulfate does not cause the sunburst to dissociate nor does it inhibit dissociation in the presence of EDTA suggesting that dissociation is not due to hydrolytic enzymes. The dissociation products were fractionated on a 977-A pore size micropore glass column. Fifteen percent of the material is excluded and appears in the electron microscope as the central circle of the sunburst. Digestion of the circles with 10(-3) M dithiothreitol (DTT) and 0.5 mg/ml proteinase K for 72 h at 37 degrees C produces 2 polysaccharide chains of 65,000 and 6,000 daltons as fractionated and sized on a 233-A pore size micropore glass column using Pharmacia dextrans as standards. The included fractions of the EDTA-treated material are subunits of the arms which contain 70% of the polysaccharide. A single polysaccharide of 6,000 daltons as measured on 233-A size glass beads and Sephadex G-75 is released from these subunits by proteinase digestion. Pharmacia dextrans are used as standard on both columns. We calculate that there would be four 65,000-dalton chains and one hundred 6,000-dalton chains per circle and fifty 6,000-dalton chains per arm. The third component of the EDTA-treated preparation is partially included on the column. It appears as linear fibrils in the electron microscope and contains polydisperse polysaccharides of several-hundred-thousand daltons. It may be an impurity since there is apparently less than 1 of the large polysaccharide chains per sunburst.


Inbreeding effects: evidence for a genetic system which regulates viability in Drosophila melanogaster populations. Mating studies on individual couples of Drosophila melanogaster allowed the structure of inbred populations in terms of egg hatchability and egg-to-adult survival to be elucidated. The comparison between inbred (from brother-sister matings) and control (randomly crossed) populations distinguished between couples sensitive and insensitive to inbreeding. Mendelian ratios were observed for this "phenotypic trait" in the progeny of single couples. These ratios and a double mating experiment indicated that a gene or gene complex implicated in morphogenetic events blocked development during embryonic and larvo-pupal stages. The expression of this lethal gene in homozygous embryos depended on the genetic makeup of both parental flies, i.e., on male and female factors which act as regulatory components. Homozygous embryos which survived the first critical phase (from fertilization to hatching) continued to develop normally until the larvo-pupal period, when they died. Lethality was also modulated by the cytoplasmic composition of the parental eggs, as shown by taxonomic analysis and the double mating experiment. The results account for lethality throughout development due to inbreeding. They lead to an estimated genetic load from laying to adult stage of one "lethal equivalent".


The effect of polyunsaturated fats on bile acid metabolism and cholelithiasis in squirrel monkeys. Squirrel monkeys (Saimiri sciureus) were fed diets containing safflower oil, butter, or coconut oil and 1 mg cholesterol/cal for 15--17 mo to examine the effect of type of fat on cholelithiasis and bile acid metabolism. Controls were fed low cholesterol diets containing an isocaloric mixture of the three fats. Cholic acid fractional catabolic rate, pool size, chenodeoxycholic acid pool size, and total bile acid pool size and excretion rate were estimated using a modification of Lindstedt's isotopic turnover procedure. The animals fed the safflower oil diet had the highest incidence of cholelithiasis (9/10) when compared to those fed butter (3/7) and coconut oil (1/7). Animals consuming the low cholesterol control diet did not develop gallstones. The butter- and coconut oil-fed groups had significantly (p less than 0.05) expanded bile acid pools when compared to controls, and the butter-fed group had a significantly increased (p less than 0.05) cholic acid fractional catabolic rate. The safflower oil group had the smallest mean bile acid pool and the highest mean lithogenic index of the cholesterol-fed groups. It was concluded that the safflower oil-fed animals had a higher incidence of cholelithiasis than the butter group because, unlike the latter group, they did not compensate for a high cholesterol intake by stimulating bile acid synthesis. The animals consuming coconut oil apparently did not absorb cholesterol to the extent of the other groups and as a result their bile did not become saturated with cholesterol.


Regulation of aflatoxin biosynthesis. III. Comparative study of adenine nucleotide pool in aflatoxigenic and non-aflatoxigenic strains. The adenine nucleotide pools were studied in toxigenic (NRRL 3240) and non-toxigenic (NRRL 3537) strains of Aspergillus flavus group in relation to aflatoxin biosynthesis. The levels of ADP and AMP were comparatively low in the non-toxigenic strain throughout the growth period. In the toxigenic strain the levels of ADP and AMP increased significantly during the stationary phase. The ATP content of the toxigencic strain had higher ATP levels during the stationary phase compared to the toxigenic strain. The inorganic phosphate levels of the non-aflatoxigenic strain were higher when compared with the aflatoxigenic strain. High levels of inorganic phosphate have been reported to be inhibitory for secondary biosynthesis including aflatoxins. The energy charge values of the non-toxigenic strain, compared to the toxigenic strain, were lower during exponential phase but higher during stationary phase. The observed changes have been correlated with aflatoxin biosynthesis.


Regulation of aflatoxin biosynthesis. 2 Comparative study of tricarboxylic acid cycle in aflatoxigenic and non-aflatoxigenic strains of Aspergillus flavus. The presence of a functional TCA cycle and its intermediates has been shown in Aspergillus parasiticus and Aspergillus flavus. The role of the TCA cycle in aflatoxin biosynthesis has been studied. In A. parasiticus the TCA cycle was activated on the second day of growth (exponential growth phase) resulting in the onset of aflatoxin biosynthesis. Pyruvate accumulation to toxic levels in A. parasiticus is suggested to shift the growth phase from exponential to stationary with the onset of aflatoxin biosynthesis. In A. flavus, a non-aflatoxigenic strain, no pyruvate accumulation was observed. Moreover, the onset of aflatoxin production in A. parasiticus was followed by a decline in the levels of TCA cycle intermediates indicating their possible utilization in secondary metabolite synthesis. Accumulation of TCA cycle intermediates in A. flavus is suggested to be due to non-diversion to aflatoxin biosynthesis.


Studies on delayed hypersensitivity to protein antigen. Induction of delayed hypersensitivity by chemically modified antigen. it was shown in our previous paper that mice primed with chemically modified bacterial alpha-amylase (BaA), which was neither cross-reactive with anti-BaA antibody nor able to induce a humoral anti-BaA response, developed enhanced responses to a subsequent challenge with native BaA and that the magnitude of the immunological memory was closely related to the priming dose of modified BaA. This paper describes the experimental conditions for induction of delayed hypersensitivity (DH) by modified BaA in relation to the development of immunological memory for antibody response to native BaA. Mice primed with either an intraperitoneal (i.p.) or subcutaneous (s.c.) injection of modified BaA in complete Freunds adjuvant (CFA) developed enhanced anti-BaA as the immunogen and modified BaA as the eliciting antigen, the relationship of anti-BaA responses to a subsequent challenge with BaA. In contrast, when mice were immunized with an s.c. injection of the modified BaA only, a significant level of DH to native BaA could be induced, as measured by the footpad reaction (FPR). The highest degree of DH was observed in mice given 50 micrograms of modified BaA. DH was detectable within 5 days and persisted for 25 days after immunization. In the reciprocal combination of native BaA as the immunogen and modified BaA as the eliciting antigen, the relationship of anti-BaA responses to DH was examined. The primary anti-BaA responses induced by an i.p. injection of large doses of BaA was markedly higher than those induced by an s.c. injection, while DH was exhibited only in mice given s.c. injection of BaA in CFA. With respect to DH to native BaA induced by the modified BaA, it was shown that C3H/He mice were high and C57BL/6 mice were low responders.


Genetic toxicology of lysergic acid diethylamide (LSD-25). The acute and the chronic psychotomimetic potentials of the hallucinogen lysergic acid diethylamide (LSD-25) have been recognized for almost 40 years. That additional types of the biological effects should have come under scrutiny was directly attributable to widespread use and abuse of this drug on a world-wide basis. Although "genetic toxicology" encompasses a broad spectrum of disciplines, including many areas of highly specialized research, perhaps the most germane, and those on which this review has concentrated, are Clastogenicity, Mutagenicity, Teratogenicity and Oncogenicity. Based on our current understanding and interpretation of the available data, the genetic toxicology of LSD provides an excellent example of Newton's "third law of motion", e.g., to every force there is an equal and opposite reaction force. From the published material it is impossible to draw clear cut conclusions regarding any of the above "problem areas" in spite of the considerable scientific effort invested. Most of the in vitro studies performed on the clastogenicity of LSD indicate either suppression of mitosis or enhanced chromosome damage. However, extrapolation of such results to the in vivo situation is very difficult. With regard to in vivo human use of the drug, no concensus is attainable as to chromosome breakage and the inconsistencies within and between studies remain inexplicable. However, several of the "controlled" investigations assessing the in vivo effect of chemically pure LSD suggest a transient increase in lymphocyte chromosome breakage. On the other hand, the results of cytogenetic studies on experimental animals are contradictory. Although human studies are nonexistent, in those experimental organisms tested, using accepted techniques, LSD proved to be, at best, a weak mutagen, if mutagenic at all. Teratogenicity studies in animals are confusing due to the multitude of organisms and plethora of discriminant parameters studied. However, with regard to man there has been ample opportunity and one can conclude that LSD is not teratogenic. As to the drug's oncogenic potential, the 3 reported cases of leukemia in LSD users are most likely the result of coincidence.


A review of the genetic toxicology of chlorinated dibenzo-p-dioxins. Information from both published and unpublished sources considered relevant to the understanding of the genetic toxicology of chlorinated dibenzo-p-dioxins is summarized in this review. Interest in writing this paper was stimulated by the fact that this class of compounds, particularly 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), has gained notoriety as an extreme environmental and industrial hazard. The potential for human exposure occurs in the work place when dioxins are formed during the synthesis of a number of commercially important compounds such as 2,4,5-trichlorophenoxyacetic acid, hexachlorophene, and pentachlorophenol. Environmental contamination may result from manufacturing processes and from dioxin contaminants in marketed products. Research on dioxins as potential mutagens was initiated because of their structural similarity to acridines, a class of known intercalating agents. To date, only 4 dioxin compounds have been evaluated for mutagenicity: the di-, tetra-, and octa-chlorinated derivatives and the unsubstituted dibenzo-p-dioxin. Since only a few of the many possible structural forms of dioxins have been tested, no definite conclusions can be made about their potential mutagenicity. Furthermore, the positive mutagenicity and cytological effects reported thus far with the few dioxin isomers examined seems to depend on the position of chlorine substitution. The most active form of the molecule is the 2,3,7,8-derivative (TCDD). Data available for assessing the mutagenic potential of TCDD are conflicting and scarce. Differences in testing results reported in these studies could be attributed to solubility problems with the test chemical, treatment protocols, purity of test samples, or toxicity. Because there are conflicting data, additional experiments are needed before the mutagenic potential of TCDD and other dioxins can be determined. Studies exploring the promoting effect of dioxins on the mutagenicity of other compounds are also recommended because experiments have shown TCDD to be an extremely active liver enzyme inducing agent that enhances the mutagenicity of certain polycyclic hydrocarbons such as 3-methylcholanthrene in vitro. The importance of discerning the hazards to human health from dioxin compounds became apparent after an accidental release of TCDD from a chemical plant contaminated the Seveso, Italy area in July 1976. This accident revealed that insufficient data were available to properly evaluate the long-term health risks posed by dioxin compounds. Several research projects were therefore initiated after the Seveso incident; it is hoped that many of the questions concerning the mutagenicity of TCDD and possibly of other dioxin congeners will be answered as a result of this work.


IgA protease production as a characteristic distinguishing pathogenic from harmless neisseriaceae. IgA proteases are extracellular enzymes of bacteria that have human immunoglobulin A of the IgA1 subclass as their only known substrate. The identification of this enzyme in neisseria prompted us to determine whether IgA protease production correlates with pathogenicity within this genus. Multiple clinical isolates of Neisseria gonorrhoeae, N. meningitidis and eight species of non-pathogenic neisseria that commonly colonize the normal human nasopharynx were examined for IgA protease activity. All N. gonorrhoeae and N. meningitidis strains were enzyme positive; all non-pathogenic strains were negative. Among meningococci, the enzyme occurred in strains carried harmlessly in the nasopharynx as well as those isolated from systemic infections. Because mucosal immune defense is largely mediated by antibodies of the IgA isotype, the finding that IgA protease activity is linked specifically to the pathogenic neisseria suggests that the enzyme may be involved in the pathogenesis of neisserial infection.


Aflatoxin is degraded by mycelia from toxigenic and nontoxigenic strains of aspergilli grown on different substrates. The ability of 9-day-old mycelia of Aspergillus parasiticus NRRL 2999 to degrade aflatoxin varied depending on the substrate used to grow the mold. Substrates which allowed substantial mycelial growth yielded mycelia which actively degraded aflatoxin. Substrates which allowed minimal growth of mycelia yielded mycelia with little ability to degrade aflatoxin. Biodegradation of aflatoxin was also strain-dependent. A. parasiticus NRRL 2999 and NRRL 3000 actively degraded aflatoxin, A. flavus NRRL 3353 was less active, and A. flavus NRRL 482 and A. parasiticus NRRL 3315 degraded minimal amounts of aflatoxins. Those aspergilli producing greatest amounts of aflatoxin also degraded aflatoxins most rapidly, whereas those strains which produced minimal amounts of aflatoxin generally degraded aflatoxins less effectively. Substrates which allowed maximum aflatoxin production also yielded mycelia which actively degraded aflatoxins, whereas media which allowed limited production of aflatoxin generally yielded mycelia with minimal ability to degrade the toxin. Although exceptions exist, generally as aflatoxin production increased so did the ability of mycelia to degrade the toxin.


[Comparative study of immunoelectrophoresis (IEF) and immunoelectroosmophoresis-immunodiffusion (IEOF-ID) used in the diagnosis of paracoccidioidomycosis]. Immunoelectroporesis (IEF) and immunoelectroosmophoresis-immunodiffusion (IEOP-ID) (1) were comparatively used in the diagnosis of 16 patients with mycologically proved paracocidioidomycosis. In IEF, 5 different precipitin arcs were found and identified with arabic numbers. Arc. '1', cathodic, present in all the patients, is assimilated to specific arcs previously described by other authors. In IEOP-ID both 'cathodic' and 'anodic' arcs were observed in all the sera. A high number of precipitin arcs were revealed by IEOP-ID technique in comparison to IEF in every case. This should be due to the presence of cathodic arcs 'I' and '2' of the immunoelectrophoregram at both sides of the IEOP-ID preparate.


[Kinetics of the temperature dependence of thermal activation and inactivation of bacterial endospores as a consequential reaction]. Reaction kinetics explains the thermal activation and destruction of bacterial endospores as a consequent reaction with the activation rate constant k 1 of the resting spores N 0 and the destruction rate constant k 2 of the heat-activated spores N ++: (formula see text). If one takes also into account the activated spores already present in a suspension, one obtains, at constant temperature, destruction curves that become straight lines when plotted semi-logarithmically or correspond to the convex and concave curves often described in the literature. The D value of destruction must be calculated from the k value of the slowest reaction. Experiments with endospores of Bac. subtilis showed that k 1 greater than k 2 at temperatures less than 100 degrees C, and k 2 greater than k 1 at temperatures greater than 135 degrees C. In case of further confirmation of this theory, far-reaching conclusions might be drawn as to the calculation of the sterilization of F value.


Evidence for splicing of interrupted immunoglobulin variable and constant region sequences in nuclear RNA. Evidence is presented that the mouse light-chain coding sequence is interrupted in a 27S nuclear RNA species, whereas the sequence is continuous in both a 13S nuclear RNA and in cytoplasmic mRNA. The discontinuity of coding regions in the 27S nuclear RNA parallels the situation found in myeloma DNA and indicates, therefore, that the removal of interruptions in the V and C regions occurs at the level of nuclear RNA.


Development of Leucocytozoon caulleryi in chick embryos infected by biting of Culicoides arakawae through shell membrane. Chick embryos were infected with Leucocytozoon caulleryi by biting of the midge, Culicoides arakawae, through the shell membrane. Schizonts of L. caulleryi were detected in the chorioallantoic membrane and most of the internal organs of embryos and of chicks after hatching. The development of schizonts was slower in embryos than in chickens. Soluble antigens of L. caulleryi were demonstrated by the precipitation test in the allantoic fluid and blood from the embryos and chicks. No erythrocytic stage of L. caulleryi, however, was observed in any embryo or chick.


Increase of liver microsomal benzo(a)pyrene monooxygenase activity by subsequent glucuronidation. Benzo(a)pyrene monooxygenase activity in rat and guinea pig liver microsomes is markedly stimulated when UDP-glucuronic acid is present in the assay. This effect is further enhanced by addition of UDP-N-acetylglucosamine, an allosteric activator of UDP-glucuronyltransferase. The results suggest a coupling between microsomal monooxygenase and UDP-glucuronyltransferase which may assist elimination of toxic compounds.


Immunochemical and clinical characteristic of series of 516 paraproteinemic patients. A series of 516 cases of paraproteinemia was analysed. According to the class of paraprotein, there were 336 cases of paraprotein IgG (65.1%), 101 paraprotein IgA (19.6%), 53 paraprotein IgM (10.3%) and 1 case of paraprotein IgD (0.2%); only light chains were found in 15 cases (2.9%) and doubled paraproteins in 10 cases (1.9%). The average age of the series was 64.2 years. Clinically, there were 315 cases of myeloma, 24 cases of Waldenström's macroglobulinemia, 126 cases of facultative paraproteinemia accompanying another disease, 16 cases of paraproteinemia in healthy persons and in 10 cases of paraproteinemia no precise diagnosis was made.


Ethosuximide and bicuculline inhibition in petit mal epilepsy. The mechanisms of petit mal epilepsy remain a mystery despite successful therapy. Previous workers have proposed that paroxysmal activity of cortical inhibitory systems plays a role in absence seizures. In this study, we have compared the effects of bicuculline, a potent convulsive agent and GABA antagonist, with ethosuximide, a drug used to treat petit mal epilepsy, on the thalamocortical motor system of the cat. Under chloralose anesthesia, sequential pairs of pulses were delivered to ventrolateral thalamus (VL) varying either pulse amplitude or interval. The evoked responses were recorded from sensorimotor cortex, analyzed on-line by computer, and plotted as an excitability curve (mean response amplitude as a function of pulse interval), or a family of threshold curves (mean response amplitude as a function of stimulus amplitude at various fixed intervals). Administration of each drug resulted in increased thalamocortical excitability and decreased threshold to stimulation for short pulse-pair intervals, with diminished duration of the excitability curve. Increased alertness was produced by both drugs. Studies with grand mal anticonvulsants demonstrated entirely different effects. Because GABA is thought to be the primary inhibitory transmitter in VL and cerebral cortex, bicuculline would be expected to result in disinhibition. The similarity of the data for ethosuximide suggests that ethosuximide also suppresses inhibition in the thalamocortical motor system and adds further to the accumulating evidence of the role of inhibitory system in petit mal epilepsy.


[Neuropathology of Chagas' disease].

[Neuropathology of Chagas' disease]. CNS involvement includes: 1) acute phase: scattered focal meningoencephalitic lesions, meningeal and cerebral edema, disseminated microgranulomas containing microgliocytes and situated in relation to cerebral blood vessels, and moderate cerebral fluid pleocytosis. Acute chagasic meningoencephalitis is always fatal, and does not become chronic, as occurres with the myocardial lesions; 2) chronic phase: tromboembolic phenomena due to the chronic myocarditis, and cerebral and cerebelar atrophy of obscure pathogenesis and without inflammatory changes. B) vegetative nervous system involvement includes: 1) acute phase: neuronal destruction, with neuronal loss of varying intensity; 2) chronic phase: visceral dilatation due to neuronal loss during the acute phase.


Current status of the search for virus in amyotrophic lateral sclerosis (ALS). Clinicians have noted resemblance between ALS with predominantly lower motor involvement and a chronic type of poliomyelitis. Occasional cases of ALS show lymphocytic infiltrations in the neuropathology. Cytoplasmic inclusion bodies as well as possible transmission of ALS to the monkey, were noted by Soviet investigators. Major questions about the latter remain, but inclusion bodies have been seen in cases outside the USSR, and search for a virus has been pursued. So far, efforts at culture, including the technique of co-cultivation, have not been successful in 3 different laboratories using material from ALS autopsied within 2 hours of death. Nor has such material and specimens from other cases produced transmissible disease in animals of laboratories where kuru, Jakob's disease and SSPE have been transmitted. Study of serum antibodies has also been negative. These negative culture, transmission and antibody studies do not exclude a viral etiology: in kuru, for example, many years passed before transmission was demonstrated, which remains the only evidence of kuru's infectivity. Evidence of an immunologic disorder in ALS has been obtained from kidney biopsies, the lack of any clinical benefit from immunosuppression may indicate that the kidney finding reveals a response to infection, though whether viral or even relevant is unknown. Two recent ALS cases will be illustrated in which virus-like particles were demonstrated post mortem by electronmicroscopy. In one, myxovirus-like tubules were seen mainly in motor neurons; in the other, picorna-virus-like crystals were found in skeletal muscles. Different viruses can cause identical disease, but 2 different viruses in different sites in ALS also suggest that at least one type of particle is an adventitious finding of no general significance. An additional impetus to continue the search is the slowly progressive type C-virus myelitis in wild mice. This disease has many dissimilarities to ALS, including different morphology of the virus, but may provide a model for slow-virus amyotrophy.


Subacute sclerosing panencephalitis (SSPE) agent in hamsters. A hamster-adapted SSPE agent was shown to cause a productive infection in weanling hamster brain, which changed to a cell-associated or defective infection coincident with the appearance of measles antibodies in serum. Antibodies to measles hemagglutinin, hemolysin and neucleocapsid antigens developed in serum, which also contained neutralizing activity for regular measles virus. The agent recovered from the brains prior to the appearance of serum antibodies was infectious in cell-free media, capable of rapidly destroying Vero-cell cultures and able to progressively destroy primary hamster brain cultures. In contrast the agent recovered from the brain after serum antibodies were present, was infectious only within cells destroyed Vero-cells ineffectively and spread slowly through primary brain tissue cultures releasing minute amounts of extracellular virus intermittently. Nevertheless, infected giant cells in the primary brain cultures contained both the HA & HL measles antigens in their cytoplasmic membranes. This in vivo conversion of a productive to a cell-associated cerebral infection appeared to be caused by the host antibody response and may mirror the initial events of human SSPE and possibly other slow or latent measles infections of the CNS.


Grating contrast detection perimetry in a patient with occipital lobe epilepsy. A new perimetry technique is based upon detection of faint gratings. This method permits assessment of visual field abnormalities that are not detectable by Goldmann perimetry or tangent screen examination. These abnormalities occurred in a 57-year-old man with a seizure disorder of left occipital origin. The technique may have advantages over conventional field study methods for the early detection of geniculocalcarine pathology.


Effect of valproic acid on spike and wave discharges in patients with absence seizures. Twenty-five patients with absence seizures were treated with valproic acid in doses from 17 to 62.5 mg per kilogram per day. Nineteen patients experienced reduction of spike and wave discharges; in 11 it was greater than 75 percent. Twenty-one patients had a reduction of the total time of spike and wave discharge. Four patients had increase of spike and wave discharges. Nineteen patients had fewer absence seizures. There was no correlation between plasma concentration of valproic acid and EEG change, but clinical improvement occurred when plasma levels of valproic acid reached 50 to 60 microgram per milliliter.


Hemiparetic seizures.

Hemiparetic seizures. In three patients hemiparesis was a manifestation of focal seizures. In all, there were electroencephalographic abnormalities and radionucleotide uptake in the contralateral hemisphere. Treatment of the seizures resulted in clearing of both paralysis and abnormal brain scan. These patients fit the diagnostic category described by Higier as a "paralytic equivalent of epilepsy without disturbance of consciousness in the form of status hemiparalyticus," and described by others as inhibitory seizures or partial seizures with subsequent hemigeneralization. The etiology of the paralysis and its relation to Todd paralysis are not clear, but it may result from excessive inhibitory discharge.


Familial chorea and myoclonus epilepsy.

Familial chorea and myoclonus epilepsy. A familial disorder was characterized by chorea, ataxia, myoclonus, convulsions, dementia, and mental retardation. In five cases, the main lesion affected cerebellar dentate nuclei, with nerve cell loss, gliosis, chromatolysis, and grumose degeneration. Fibrous glial cell proliferation was detected in the globus pallidus.


Imipramine in absence and myoclonic-astatic seizures. A double-blind crossover study with imipramine was conducted in 10 patients with absence and myoclonic-astatic seizures who had not responded to conventional medications. Imipramine produced a significant initial decrease in seizure frequency in 5 of the 10 patients, and in 2 patients the beneficial effect was maintained for more than 1 year. An open trial of imipramine in another 16 patients showed an initial reduction in seizure frequency in 10 patients (63 percent), and this decrease persisted for more than 1 year in 4 patients (25 percent). The effect of imipramine on the EEG did not always correlate with the clinical response. Serum content of imipramine in the patients who showed a long-term response was 40 to 120 ng per milliliter, on a total daily dose of 0.7 to 3.5 mg per kilogram. These results suggest that imipramine is a valuable addition to the treatment of seizures.


Complex partial status epilepticus: case report and proposal for diagnostic criteria. A child had complex partial status epilepticus after resection of a craniopharyngioma. The status epilepticus was manifested by confusion and documented electroencephalographically by continuous focal seizure patterns in the right temporal region. Complex partial status epilepticus is an electroclinical syndrome of prolonged or repetitive complex partial seizures (with continuous interictal confusion) accompanied by electroencephalographic seizure patterns, which are either focal (usually temporal lobe) or secondarily generalized from a focal pacemaker.


Electrophysiological investigation of cortico-hypothalamic relations in cats. Projections of different parts of the orbito-frontal cortex, the basal temporal cortex, and the hippocampus on hypothalamic nuclei were studied by recording focal responses in acute experiments on cats anesthetized with pentobarbital and chloralose. The proreal gyrus was shown to have local projections in the latero-dorsal zones of the preoptic region, in the postral parts of the medial forebrain bundle, and also in the region of the lateral and posterior hypothalamus with the mammillary bodies. The orbital gyrus projects mainly to the latero-dorsal portions of the forebrain bundle, the latero-ventral part of the preoptic region, and the region of the lateral and latero-dorsal hypothalamic nuclei; projections from the orbital gyrus are relatively diffuse in character. The basal temporal cortex has diffuse projections in the central part of the preoptic region, in the latero-ventral parts of the medial forebrain bundle, and in the lateral mammillary body. No marked foci of activity were found in the hypothalamic structures during hippocampal stimulation. Diffuse projections of the hippocampus were traced in the ventral part of the preoptic region and the ventral regions of the medial forebrain bundle, and also in the lateral hypothalamus and in the lateral mammillary nucleus.


[Traumatic chylothorax. A further indication for total parenteral nutrition]. Successful and rapid resolution of a serious cases of traumatic chylothorax by means of conservative management with TPN is reported. This method is clearly indicated as a mean of making up the calorie and amino acid need when litres of chyle are being lost every day. In addition, by resting the digestive tract it brings about a massive decrease in the production of lymph in the mesenteric district and thus leading to easier and earlier sufficiency of the collateral lymph drainage routes. The rapid decrease in quantity and the change over from chylous to serous chest drainage liquid after TPN are evidence of its soundness. An immediate lymphographic control revealed complete section of the duct. Two months later, collateral diaphragmatic and azygos circulation was observed. It is felt, therefore, that TPN extends the range of conservative management of posttraumatic and postoperative chylothorax.


A comparison of intralingual and intravenous epinephrine before and during cardiovascular depression. Dose-response methodology was used to evaluate the cardiopulmonary effects of epinephrine administered intravenously and intralingually to normotensive and acutely hypotensive dogs and monkeys. Results indicate that the intralingual route is much less effective than the intravenous route and that conventional doses of emergency drugs injected intralingually may not afford sufficient resuscitative effects to be lifesaving during cardiovascular depression.


Connective tissue reactions to acid glutaraldehyde. Acid glutaraldehyde, 2 per cent and 1 per cent, along with sodium hypochlorite, 5.5 per cent, was tested on the connective tissue of rabbits and rats. Two per cent acid glutaraldehyde was very destructive, whereas the NaCIO and 1 per cent acid glutaraldehyde were moderately irritating.


Depression of primate spinothalamic tract neurons by iontophoretic application of 5-hydroxytryptamine. The effects of iontophoretic applications of 5-hydroxytryptamine (5-HT) were tested upon primate spinothalamic tract neurons recorded extracellularly in the spinal cord of anesthetized monkeys. The activity of most high threshold and wide dynamic range spinothalamic tract cells was depressed. 5-HT also reduced the responses of the cells to glutamate pulses which by themselves had a powerful excitatory action. It is concluded that 5-HT has a depressant action upon the postsynaptic membranes of spinothalamic tract cells, although the action has a slow time course. The observations are consistent with, but by no means prove, the hypothesis that serotonergic  pathways descending from the brain stem produce a postsynaptic inhibiton of spinothalamic tract neurons.


[Determination of circulating immune complexes: comparison between agglutination inhibition and C1Q precipitation in polyethylene-glycol-EDTA (author's transl)]. Three different methods for the determination of circulating immune complexes were compared : precipitation of radioiodinated C1q in polyethyleneglycol-EDTA, inhibition of IgG-coated latex particles agglutination by C1q or polyclonal rheumatoid factor. Normal values and their upper limits as well as the reproducibility of each technique are presented. The possible effect of several factors was investigated : age, sex, anticoagulants, freezing and thawing, contamination by DNA or endotoxin. Comparison of the results obtained with normal or pathological sera revealed a positive correlation between the three techniques. However, the discrepancies noted with some sera make the use of at least two different methods highly recommendable for the study of circulating immune complexes in disease.


The relationship between intracellular and extracellular potassium in normal and malnourished subjects as studied in leukocytes. Leukocyte potassium has been measured in normal subjects and in malnourished children with and without edema both on admission and during recovery. In nonedematous malnourished children the potassium content was low (328 mmol/kg dry solids) and took 2-3 weeks of rehabilitation to return to normal (374 mmol/kg dry solids). Leukocytes from edematous children had normal intracellular potassium values. However, 5 days on a maintenance diet reduced the intracellular potassium in the children with kwashiorkor to a value similar to that found in marasmus. Plasma potassium was significantly lower in kwashiorkor (3.43) than in marasmus (4.74), The relationship between external potassium and internal potassium in normal leukocytes was measured (Fig. 1) and the values found in severe malnutrition compared with normal. It was found that in nonedematous malnutrition intracellular potassium was low compared to the predicted value, whereas in kwashiorkor, although the mean values were normal, no relationship between external potassium and intracellular potassium could be domonstrated. It is concluded that in the leukocyte malnutrition alters either the passive permeability of the membrane to potassium or the active transport of potassium, or both.


The practical significance of lactose intolerance in children. Lactose intolerance is observed in black and Mexican-American children by age 3 years, and it probably occurs in other non-northern European ethnic groups at a similar age. However, intolerance to the consumption of 250 ml of milk apparently is rarely seen in preadolescents. Current research on the response of adolescents to hydrolyzed lactose milk suggests that the symptoms observed in lactose-intolerant subjects after milk ingestion may be unrelated to lactose or may be mild enough to be of little practical significance. The effects of undigested lactose on nutrient absorption has received little attention, but preliminary data suggest that this is not a problem, except perhaps when overall intakes are marginally adequate.


Effects of red light and loud noise on the rate at which monkeys sample the sensory environment. Monkeys, given the opportunity to move between two featureless chanbers, 'sample' first one, then the other in a way which reflects a Poisson decision process. The rate of sampling is higher in red light than in blue and in loud noise than in quietness. We suggest that monkeys 'tune' their sampling rate to the a priori probability of change in the environment.


Regulation of TSH secretion in rats chronically exposed to heat (34 degrees C). Previous studies have shown that in heat exposed rats, a decreased plasma T4 concentration was associated with a normal biologically active TSH concentration. This study was designed to clarify this apparent discrepancy in the regulation of TSH secretion. In experimental rats (34 degrees C for 25 days) and controls (25 degrees C), plasma total T4 was 3.2 vs. 5.7 x 10(-8) mol/l. (P less than 0.01), plasma total T3: 2.4 vs. 5.7 x 10(-10)mol/l. (P less 0.01) and plasma TSH: bioassay 0.34 vs 0.29 mU/ml (ns), radioimmunoassay: 1.04 vs. 0.87 microgram RP1/ml (ns). After TRH, plasma TSH increased identically in the two groups. In heat-exposed rats, the dialysable fraction of T4 and T3 were were increased: 0.032 vs. 0.020% (P less than 0.05) and 0.102 vs. 0.086% (P less than 0.05), respectively; accordingly, free T4 concentration was normal and that of free T3 was low; total plasma proteins were slightly increased. It is concluded that in heat-exposed rats: (1) plasma thyroid hormone binding activity was decreased as shown by the association: decreased plasma total T4--elevated free T4 fraction. The normality of the free T4 concentration accounted for the normal plasma TSH. (2) the combination of normal plasma TSH, normal plasma free T4, low plasma free T3 concentrations would suggest that T4 is predominantly involved in the regulation of TSH secretion.


Organochlorines in fish and crabs from the Kristiansand fjord in Norway. The levels of sum-DDT, PCBs, and HCB in fish liver and crab hepatopancreas from the Kristiansand fjord area in Norway have been determined (fig. 1). The respective mean levels (fat weight basis) in stationary fish species and crabs are given in table I. The levels of PCBs and sum-DDT were about the same, and the HCB level two to one hundred times higher than corresponding levels reported for codfish (liver) from several harbours along the Norwegian coasts (Brevik et al. in press). The levels calculated on a wet weight basis, found is stationary fish from the harbour of Kristiansand and Topdals-fjord were two to three times higher than those in crabs. Calculated on a fat weight basis, however, the levels in stationary fish and crabs were much more similar (table II). The harbour area was more contaminated with PCBs and HCB than the other sites examined. It seems impossible, however, on the basis of present data to further pinpoint sources of the relatively high degree of HCB contamination in the Kristiansand fjord area.


["Oddipathies" (author's transl)].

["Oddipathies" (author's transl)]. The modern anatomy has notably increased the knowledge of details, in biliary surgery, mainly about the sphincter of Oddi, thanks to the use of an adequate radio diagnosis set in the operating room. The term of Odditis is too widely used. It must be replaced by Oddipathies, each disease being defined by its nature and its precise location. Medical and surgical therapy will be adapted to this millimetric scale.


Electrophoretic strand separation of long DNAs with poly (U,G) in agarose gels. We have found that binding of poly(U,G) to single-stranded DNA decreases its mobility in 0.3% agarose gels. Differential binding to the complementary strands of denatured duplex DNA provides a simple method for strand separation. The method is shown to work with bacteriophage lambda DNA, adenovirus DNA and mtDNA for Tetrahymena pyriformis. In all cases the strand that binds more poly(U,G) in CsCl gradients also binds more in gels. The separated strands can be directly blotted from the gel onto nitrocellulose filters and used for hybridization experiments.


Recognition of individual procaryotic and eucaryotic transfer-ribonucleic acids by B subtilis adenine-1-methyltransferase specific for the dihydrouridine loop. Bulk tRNA from yeast and Rat liver can be methylated in vitro with -adenosylmethionine and B, subtilis extracts. The sole product formed is 1-methyladenosine (m1A). This tRNA (adenine-1) methyltransferase converts quantitatively the 3'-terminal adenosine-residue in the dihydrouridine-loop of tRNAThr and tRNATyr from yeast into m1A. Out of 16 eucaryotic tRNAs with known sequences 6 accepted methyl groups, all at a molar ratio of 1. These tRNAs have in common an unpaired adenosine-residue at the specific site in the sequence Py-A-A+-G-G-C-m2G. Out of 12 tRNAs from E. coli 6 served as specific substrates. These E. coli tRNAs also have an unpaired adenosine-residue at the 3'-end of the D-loop. Besides restrictions in primary structure intact secondary and tertiary structure is important for recognition of the specific tRNAs by the enzyme.


Messenger RNA abundance and lifetime: a correlation in Drosophila cells but not in HeLa. Messenger RNA in eukaryotes is comprised of several abundance classes. Also, the decay of these unstable molecules shows at least two very different lifetimes. Two independent techniques are used here to examine the relation between message abundance and lifetime in cell lines from very different organisms. The methods give consistent results for each cell line; however, the two cell types show very different results. In brosophile cells, slowly decaying sequences fall in the abundant class while scarce sequences turn over rapidly. In contrast, in HeLa cells the abundant and scarce message classes are each comprised of long- and short-lived molecules.


[Enlarge indications for controlled respiration (author's transl)]. Controlled respiration should have a place not only in cases of hypoventilation but also in the treatment of comatose and hyperventilating persons. Hyperventilation is liable severely to interfere with the blood supply to the brain, and this disturbance, in conjunction with the primary disease responsible for the comatose condition, such as hyperglycaemia, diabetes or cerebral trauma, may be a contributing factor to the lethal outcome. Controlled respiration helps towards regulation of the cerebral circulation and of the acid-base balance and provides improved conditions for normalization of the disturbed metabolism and thus greatly improves the prognosis of these cases.


[A study of the carbohydrate and electrolyte balance of 10 surgical patients during 7-days' infusion therapy (author's transl)]. For postoperative parenteral feeding fructose proved preferable to glucose and xylitol. Although the infusions were started pre-operatively sodium deficiency and a fall in serum osmolarity developed during the postoperative stage. Administration of potassium to normalize lowered serum potassium levels was needed only on the first and second postoperative day. Serum calcium levels fell during the 7-days' period of observation but remained within the limits of normal. If parenteral feeding is to be continued for longer periods determination of the phosphorus balance is advisable to avoid excessive depletion of the endogenous phosphorus stores. Estimations of urinary osmolarity and urine volume indicated that fluid uptake was adequate.


Pharmacokinetics of drugs used for petit mal 'absence' epilepsy. Ethosuximide, clonazepam and valproic acid differ in their chemical structures and properties. They appear to be well absorbed when given by mouth, but their patterns of distribution within the body are different. If these 3 drugs have a common mode of action, the virtual restriction of valproate to extracellular water suggests that this common mode of action is likely to involve receptors on the neuronal cell surface. Even if there is no common mode of action the apparent volume of distribution of valproate is consistent with its known effects on enzymes of the GABA shunt, and in particular on those shunt enzymes which are involved in the transmitter GABA pool in the region of synapses. The 3 drugs also show differences in elimination rate, which make it desirable to give valproate 3 times a day and clonazepam twice a day, whereas ethosuximide could reasonably be given once daily without undesirably wide fluctuations in plasma drug level over the dosage interval. Further studies of the pharmacokinetics of ethosuximide, clonazepam and valproate are still needed, but sufficient data are already available to provide some basis for rational use of these drugs in treating petit mal 'absence' epilepsy.


Mechanism of integrating foreign DNA during transformation of Bacillus subtilis. Genes encoding thymidylate synthetase from Bacillus subtilis bacteriophages were cloned in Escherichia coli. Chimeric plasmids pCD1 and pCD3 were constructed from site-specific endonuclease digests of bacteriophage phi3T DNA cloned in pMB9 in E. coli. Similar cloning techniques with bacteriophage beta22 DNA yielded chimeric plasmids pCD4, pCD5, and pCD6. Endonuclease digests of DNA from pCD1 and pCD3 propagated in E. coli or from DNA isolated from bacteriophage phi3T propagated in B. subtilis transformed B. subtilis from Thy- to Thy+. Intact DNA from bacteriophage beta22, endonuclease digests of beta22 DNA, and a chimeric plasmid (pCD5) composed only of the thybeta22 gene and pMB9 did not transform B. subtilis from Thy- to Thy+ even though pCD5 could transform Thy- E. coli to Thy+. However, if the thybeta22 fragment from pCD5 was introduced into another chimeric plasmid, pCD2, that contains a region of homology to the chromosome of B. subtilis in addition to pMB9, transformation of Thy- clones of B. subtilis was possible. Furthermore, Southern hybridization analyses of the digests of chromosomal DNA from the Thy+ transformants established that the entire chimeric plasmid was incorporated into the chromosome of B. subtilis. Treatment of these plasmids with site-specific endonucleases abolished transformation. These results indicated that the entire chimeric plasmid can be incorporated into the chromosome of B. subtilis by a Campbell-like model. Therefore, an additional mechanism for transformation exists whereby plasmids can be integrated if sufficient chromosomal homology is maintained.


Purine metabolism in cultured human fibroblasts derived from patients deficient in hypoxanthine phosphoribosyltransferase, purine nucleoside phosphorylase, or adenosine deaminase. Rates of purine synthesis de novo, as measured by the incorporation of [14C]formate into newly synthesized purines, have been determined in cultured human fibroblasts derived from normal individuals and from patients deficient in adenosine deaminase, purine nucleoside phosphorylase, or hypoxanthine phosphoribosyltransferase, three consecutive enzymes of the purine salvage pathway. All four types of cell lines are capable of incorporating [14C]formate into purines at approximately the same rate when the assays are conducted in purine-free medium. The purine overproduction that is characteristic of a deficiency in either the transferase or the phosphorylase and that results from a block in purine reutilization can be demonstrated by the resistance of [14C]formate incorporation into purines to inhibition by hypoxanthine in the case of hypoxanthine phosphoribosyltransferase-deficient fibroblasts and by resistance to inhibition by inosine in the case of purine nucleoside phosphorylase-deficient fibroblasts.


Neoplastic transformation of rat mammary cells exposed to 7,12-dimethylbenz[alpha]anthracene or N-nitrosomethylurea in cell culture. Primary cultures of mammary cells from virgin Lewis rats were seeded at 5 X 10(5) cells per cm2 in medium 199 supplemented with 10% fetal calf serum, insulin (5 microgram/ml), prolactin (5 microgram/ml), estradiol (5 ng/ml), progesterone (0.5 microgram/ml), and hydrocortisone (0.5 microgram/ml). On the second or third day of culture, cells were exposed to either 7,12-dimethylbenz[alpha]anthracene (0.1 microgram/ml for 24 hr) or N-nitrosomethylurea (80 microgram/ml for 2 hr). The cells were later assayed for transformation by transplanting 10(6) or 10(5) cells into gland-free mammary fat pads of 3-week-old female hosts. Untreated cells produced only normal mammary outgrowths when transplanted. Cells treated with 7,12-dimethylbenz[alpha]anthracene or N-nitrosomethylurea produced abnormal outgrowths in 11% of the transplants. These abnormal outgrowths ranged from rapidly growing adenocarcinoma to alveolar and ductal hyperplastic lesions. The results indicate that rat mammary epithelial cells can be transformed by exposure to chemical carcinogens in culture and thus represent a potential in vitro model for epithelial cell transformation.


Origin and direction of replication in mitochondrial DNA molecules from Drosophila melanogaster. From a consideration of the various structural forms of partially replicated mitochondrial DNA (mtDNA) molecules from Drosophila melanogaster embryos observed in the electron microscope, it appears that the majority of molecules are replicated by a highly asymmetrical mode in which synthesis on one strand is up to 99% complete before synthesis on the second strand is initiated. Replication of the minority of molecules involves a more nearly symmetrical synthesis of the two complementary strands. The D. melanogaster mtDNA molecules have physical features with respect to which the origin and direction of replication could be mapped. These features are (i) a single region accounting for approximately 25% of the circular contour length and rich in adenine + thymine, and (ii) four EcoRI sites, all of which lie outside of this region. Molecules of this mtDNA were subjected to partial denaturation, EcoRI  digestion, or partial denaturation after EcoRI digestion and the products were examined in the electron microscope. Complex forms interpretable as originating from replicative intermediates were observed. The size and structure of the components of these complex forms were wholly consistent with the interpretation that, in all of these mtDNA molecules, replication originates at, or close to, the center of the adenine + thymine-rich region and proceeds unidirectionally around the molecule toward the EcoRI site lying closest to the adenine + thymine-rich region.


Mechanisms of antibody diversity: multiple genes encode structurally related mouse kappa variable regions. The complete amino acid sequences of the variable regions of three mouse Vkappa-21 kappa chains (A22, T111, and CB101) and one partial sequence (B32) have been determined and are compared to four previously reported Vkappa-21 variable regions. These eight kappa variable region sequences have, with the exception of an amide difference at residue 1, identical amino-terminal 23-residue sequences, all are of the same length, and all have extensive amino acid sequence homology throughout the variable region. When these eight variable regions are grouped by sequence homology, five different groups (Vkappa-21A, B, C, D, and E) are present whose members share common sets of amino acids within a group. Three groups of similar homology each contains at least two members (M63 and AB22 in Vkappa-21B; M321 and T124 in Vkappa-21C; and M70 and B32 in Vkappa-21A). The repetition of these five characteristic subgroup sequences in this relatively small sample indicates that these subgroups are isotypes which are controlled by separate germline genes. It is unlikely that these sequences could have been randomly somatically generated in different animals from a single germ-line gene (parallel mutation). Although a limited number of comparisons are available, the sequence differences within the Vkappa-21A, B, and C isotypes are limited to complementarity-determining regions and may have resulted from somatic mutations. The kappa chains comprising the Vkappa-21 isotypes offer a unique opportunity to compare the genetic interpretations of the primary amino acid sequence data with the nucleic acid hybridization data.