| [various properties of rifr mutants of the plague agent]. | the properties of the rifr mutants of four vaccinal and two natural strains of the plague bacillus were studied. the frequency of the mutants not growing on the complete nutrient medium after increasing the cultivation temperature to 37 degrees c averaged to 3.10(-1). the frequency of the loss of every of the three known autonomous plasmids or combinations of the 6-md and 65-md plasmids was n.10(-1). in the mutants of some strains with the preserved 47-md plasmid sensitivity to the ca2+ deficien ... | 1991 | 1953182 |
| integration of the plasmid encoding the synthesis of capsular antigen and murine toxin into yersinia pestis chromosome. | yersinia pestis, the causative agent of plague, usually carries three plasmids. the largest of them, a 60 megadalton (mda) replicon designated pfra determines the synthesis of capsular antigen (fraction i) and murine toxin. both products are involved in the expression of virulence. previously, several cases of integration into the bacterial chromosome of the calcium dependence plasmid common to pathogenic yersinia species have been described. in this study, using the southern hybridization metho ... | 1991 | 1961108 |
| [the peptidase activity of a cellular extract of the causative agent of plague]. | peptidase activity of yersinia pestis cell extract was studied by the hydrolysis of synthetic and some natural substrates, as well as the hydrolysis of fluorogenic aminopeptidase substrates. all peptides and fluorogenic substrates under test were split by y. pestis cell extract, the splitting of alanylaminopeptidase substrate being linked with at least two enzymes of this cell extract. | 1990 | 1973325 |
| [the phenomenon of pilus formation in the interaction of yersinia pestis with macrophages in experimental animals]. | according to the data of the enzyme immunoassay, adhesion pili were expressed by y. pestis cells eb76 after their cultivation in media with ph similar to that of phagolysosomes. the expression of adhesion pili was found to occur 18 hours after the contact of apiliate cells eb76 with a monolayer of native, but not inactivated (at 56 degrees c for 30 minutes) macrophages of the peritoneal exudate of white mice and guinea pigs. purified adhesion pili possessed cytotoxic action and inhibited the dig ... | 1990 | 1973326 |
| codon 72 polymorphism of the tp53 gene. | | 1990 | 1975675 |
| close relationships between neopterin and beta-2-microglobulin levels in intravenous drug abusers. | serum from 36 intravenous drug abusers without acquired immunodeficiency syndrome (aids) or aids-related complex were tested for concentrations of neopterin and beta 2-microglobulin. the seroprevalence of human immunodeficiency virus (hiv) antibody in this group was 50%. previous studies of this group showed that the hiv antibody positive patients had significant increases in hla-dr expression on peripheral blood lymphocytes and increases in serum soluble cd8 antigen. both neopterin and beta 2-m ... | 1990 | 1976599 |
| [the effect of the adhesion pili of yersinia pestis on the physiological activity of the leukocytes and macrophages in experimental animals]. | the data on the influence of the preparation of y. pestis adhesion pili on peritoneal macrophages in white mice and guinea pigs are presented. y. pestis adhesion pili have been found to induce the dose-dependent increase of cell chemiluminescence. they have also been found to induce a number of biochemical changes in target cells: the secretion of myeloperoxidase, an increase in the activity of camp-dependent protein kinases. | 1990 | 1978453 |
| molecular biology of the cuticle collagen gene families of caenorhabditis elegans and haemonchus contortus. | | 1990 | 1978527 |
| a cloned chromosomal dna fragment which differentiates yersinia pestis from yersinia pseudotuberculosis and yersinia enterocolitica. | chromosomal dna from reference yersinia strains was digested individually with 9 restriction endonucleases. dna fragments were separated and analyzed by electrophoresis through agarose gels. the clearest fragment patterns were obtained when ecori was employed. the y. pestis fragment pattern obtained after the use of this enzyme showed the presence of a unique dna fragment with molecular mass 1400 bp. this dna fragment was cloned, purified, labeled with 32p and then used to probe ecori digests of ... | 1990 | 1980253 |
| [the effect of the "37 degrees c--low ph" signal on cells of yersinia pestis]. | it is established that the synthesis of adhesion piles registered by the results of immunoenzyme analysis and immunoblotting starts 90 min after the action on apilated cells of plaque microbe eb-76 of the signal "37 degrees c-low ph" (cultivation at 37 degrees c and acidic ph). under these conditions a part of cell piline is in a form connected with cells and only inconsiderable part (to 20%) is represented in a form of "classical" piles possessing hemagglutinating activity. it is shown that in ... | 1990 | 1982158 |
| woodchuck hepatitis virus is a more efficient oncogenic agent than ground squirrel hepatitis virus in a common host. | chronic infection with hepatitis b viruses (hepadnaviruses) is a major cause of hepatocellular carcinoma (hcc), but the incubation time varies from 1 to 2 years to several decades in different host species infected with indigenous viruses. to discern the influence of viral and host factors on the kinetics of induction of hcc, we exploited the recent observation that ground squirrel hepatitis virus (gshv) is infectious in woodchucks (c. seeger, p. l. marion, d. ganem, and h. e. varmus, j. virol. ... | 1991 | 2002538 |
| stereoselective transport of baclofen across the blood-brain barrier in rats as determined by the unit impulse response methodology. | the blood-brain barrier transport characteristics of racemic baclofen and the separate r- and s-enantiomers have been determined in vivo in rats by using the unit impulse response methodology. transport rate was determined as blood-brain barrier clearance, the volume of plasma per unit time cleared of baclofen by transport across the blood-brain barrier. plasma elimination kinetics and csf elimination kinetics did not differ among racemic baclofen and the r- and s-enantiomers. transport of each ... | 1991 | 2023878 |
| stereoselective transport of baclofen across the blood-brain barrier in rats as determined by the unit impulse response methodology. | the blood-brain barrier transport characteristics of racemic baclofen and the separate r- and s-enantiomers have been determined in vivo in rats by using the unit impulse response methodology. transport rate was determined as blood-brain barrier clearance, the volume of plasma per unit time cleared of baclofen by transport across the blood-brain barrier. plasma elimination kinetics and csf elimination kinetics did not differ among racemic baclofen and the r- and s-enantiomers. transport of each ... | 1991 | 2023878 |
| immune responses of two mastomys sibling species to yersinia pestis. | this study assessed the in vitro cell-mediated immune responses of mastomys natalensis, with a diploid chromosome number of 2n = 32, and mastomys coucha, with a diploid chromosome number of 2n = 36, to yersinia pestis. splenic mononuclear (mn) cells of uninfected m. natalensis proliferated in response to crude fraction 1 of y. pestis and two subfractions derived from fraction 1 in vitro. proliferation was dose dependent and followed the time kinetics of other well-known mitogens. further charact ... | 1991 | 2037358 |
| angiotensin converting enzyme inhibition. systemic and regional hemodynamics in rats and humans. | the systemic and regional hemodynamic effects of angiotensin i converting enzyme inhibitors (aceis) have been investigated using different experimental methods (pulsed doppler, radioactive microspheres), either in rats (normotensive nt or genetically hypertensive shrs) or in humans (healthy volunteers or patients with congestive heart failure chf). all aceis decreased systemic vascular resistance but the profile of their peripheral vasodilating properties was heterogeneous. acei-induced vasodila ... | 1991 | 2043315 |
| sir frederick hobday memorial lecture. all wind and water: some progress in the study of equine gut motility. | | 1991 | 2044514 |
| juxtamedullary afferent arteriolar responses to p1 and p2 purinergic stimulation. | we assessed the responsiveness of rat juxtamedullary afferent arterioles to purinergic stimulation using the in vitro blood-perfused juxtamedullary nephron technique combined with videomicroscopy to allow direct measurement of arteriolar inside diameter. to minimize the contribution of endogenously formed angiotensin ii, all rats were pretreated with enalaprilat (2 mg i.v.) for 30 minutes before the right kidney was isolated and prepared for study. renal perfusion pressure was set at 110 mm hg a ... | 1991 | 2045147 |
| central effect of endothelin on neurohormonal responses in conscious rabbits. | it has been shown that endothelin-1 (et-1) binding sites exist in the central nervous system and that the injection of intracerebroventricular et-1 induces a pressor response. therefore, we determined the neurohormonal and cardiovascular responses to intracerebroventricular et-1 (25 pmol/kg) in conscious rabbits with chronically instrumented electrodes on the renal sympathetic nerve. intracerebroventricular et-1 provoked a prompt increase in arterial pressure and in renal sympathetic nerve activ ... | 1991 | 2045164 |
| augmentation of endothelium-independent flow constriction in pial arteries at high intravascular pressures. | the effects of an increase in intraluminal pressure and flow on the diameter and active smooth muscle tone of pial arteries was studied in perfused segments. resistance arteries (approximately 250-300 microns i.d.) were perfused under controlled pressure and flow conditions, and changes in arterial diameter registered with an automated video device. in any particular segment, diameter measurements were normalized to that observed at 5 mm hg. changes in active wall force were determined by relati ... | 1991 | 2045168 |
| the us: transmission of hiv in a dental office. | | 1991 | 2045229 |
| fumonisin mycotoxins and equine leukoencephalomalacia. | | 1991 | 2045319 |
| plague and tularemia. | human plague is a local or systemic flea-transmitted infection caused by yersinia pestis. it is maintained in well established enzootic foci among wild rodents. this article discusses the clinical findings in plague, diagnosis, treatment, and prevention of plague, and management of contacts of human plague cases and of exposures to epizootic plague. tularemia shares many features with plague but is widespread in animal and arthropod vector populations and essentially throughout the united states ... | 1991 | 2051013 |
| biological warfare and infection control. | though many agents have been proposed as potential biological weapons, the feasibility of biological warfare is largely a matter of conjecture. the unpredictable and indiscriminate devastation caused by natural epidemics during wartime should warn us of the dangers of employing microbes as weapons. | 1991 | 2071880 |
| contralaterally projecting lamina viii interneurones in middle lumbar segments in the cat. | peripheral input to lamina viii interneurones was investigated by using extracellular and/or intracellular records from them. the interneurones were located in the l4-l5 spinal segments and projected to contralateral motor nuclei in the l7 segment. they constituted a non-homogeneous population but their input from muscle afferents (mainly group ii afferents of quadriceps, flexor digitorum longus and pretibial flexors and group i afferents of triceps surae and hamstring nerves) and from cutaneous ... | 1990 | 2073610 |
| [the design of a diagnostic test system based on magnetic sorbents and liposomes]. | the results obtained in the study of the possibility of using magnetic sorbents for the construction of a diagnostic assay system based on the antigen-antibody interaction are presented. as a model, yersinia pestis capsular antigen and immunoglobulins to it have been used. a solid-phase immunofluorescent liposomal assay method has been developed; this method can be used for the detection of biopolymers in the sample under study and for the determination of their activity. | 1990 | 2075755 |
| [the utilization of heme iron by yersinia pestis in human blood and blood sera]. | y. pestis, the causative agents of plague, have been found to be incapable of using heme iron bound to haptoglobin and hemopexin complexes in human blood and blood serum, and protein components of the serum are not the factors inhibiting this process. at the same time iron of free hemoglobin can be successfully utilized by y. pestis in the systems used in this study. on the contrary, hemin not only produces any stimulating effect on the growth of y. pestis in blood serum, but leads to the death ... | 1990 | 2075759 |
| [seroepidemiologic survey on plague in an endemic zone: cumulative results: 1987-1990]. | plague is a bacterial disease, induced by yersinia pestis growth in rodents, with human transmission by fleas. in numerous cases, lymph node reaction is important. this survey (329 patients and contacts) is the most extensive ever realised, associating plasmidic virulence and immunity studies. from the results, we can retain that: all the strains were 47 plasmid+. the immunity was precocious, specific, of high titer and persistent. in conclusion, in plaque endemic zone, high bacillus circulation ... | 1990 | 2078084 |
| homocysteic acid as an endogenous excitatory amino acid. | | 1990 | 2080552 |
| identification and characterization of a gene and protein required for glycosylation in the yeast golgi. | the mnn2 gene of saccharomyces cerevisiae has been cloned by complementation of the mnn2 mutant phenotype scored by a change in cell surface carbohydrate structure resulting from a lack of alpha 1----2-mannose branching in the outer chain. the gene was subcloned as a 3 kb dna fragment that integrated at the mnn2 locus, and a gene disruption yielded the mnn2 phenotype. a lacz-mnn2 gene fusion protein, produced in escherichia coli, was used to raise a specific antiserum that recognized a 65 kd wil ... | 1990 | 2082155 |
| dietary carbohydrate source and copper bioavailability. | the accentuation of deficiency signs in male rats indicates that a high intake (60% of calories) of fructose and sucrose decreases the bioavailability of dietary copper as compared with the bioavailability when starch is the carbohydrate source. while there are few quantitative data, it appears that under these conditions copper bioavailability may be 30% lower in the presence of sucrose or fructose. this phenomenon has not been observed in female rats, and there is little evidence that the resu ... | 1990 | 2082222 |
| interaction of lectins with yersinia pestis strains. | the ability of lectins to interact with yersinia pestis strains isolated from rodent fleas and human biological fluids, obtained from different geographic areas, was examined. lectins of canavalia ensiformis, ulex europaeus, phaseolus vulgaris, and triticum vulgaris, as well as a new autochthonous lectin of swartzia pickellii of undefined specificity, were used. most of the y. pestis strains did not agglutinate with u. europaeus or c. ensiformis lectin. however, p. vulgaris lectin agglutinated s ... | 1990 | 2091525 |
| immunochemical localization of the fraction-1 antigen, a virulence determinant of yersinia pestis. | the distribution of yersinia pestis fraction-1 (f1) antigen was analyzed in cells grown at 28 degrees c and 37 degrees c. fractionation of y. pestis cells followed by analysis in sds-polyacrylamide gel electrophoresis indicated that the mature form of the f1 antigen is localized in the extracellular matrix and in the cytoplasm. localization of the f1 antigen was confirmed by immunoblots and a single peptide with a molecular weight of 17,000 daltons was recognized. electron microscopy of y. pesti ... | 1990 | 2094179 |
| [aminoacyl-trna synthetases (codases) and their noncanonical functions]. | the aim of this review is to summarize the data obtained in the author's laboratory during the last decade. the main objects of these investigations were mammalian aminoacyl-trna synthetases, mainly bovine tryptophanyl-trna synthetase (ec 6.1.1.2). the data are discussed and compared with those described in literature. in the course of these studies it turned out that some properties of mammalian aminoacyl-trna synthetases for instance, nuclear location of some of the synthetases, presence of ex ... | 1990 | 2094804 |
| comparative studies of yersinia pestis outer membrane isolation techniques and their potential use in plaque epidemiology. | in the present study three techniques for obtaining outer membrane enriched fractions from yersinia pestis were evaluated. the techniques analysed were: differential solubilization of the cytoplasmic membrane with sarkosyl or triton x-100, and centrifugation in sucrose density gradients. the sodium dodecyl-sulfate polyacrylamide gel electrophoresis (sds-page) of outer membrane isolated by the different methods resulted in similar protein patterns. the measurement of nadh-dehydrogenase and succin ... | 1990 | 2095628 |
| [the isolation and characteristics of variant plague microbes not producing the capsular antigen]. | fifteen stable variants of yersinia pestis strains exhibiting different degrees of virulence for white mice and guinea pigs were obtained. multiple passages of the organisms at 37 degrees c in a fluid nutrient medium containing antiplague agglutinating serum were found to be the most efficient method for obtaining noncapsular forms of the plague agent. acquisition of the fra(-) phenotype both by wild and laboratory strains was not associated with a loss of the high-molecular plasmid by cells but ... | 1990 | 2097497 |
| [the tissue heterogeneity of mononuclear phagocyte system cells interacting with yersinia pestis]. | the work deals with the determination of the heterogeneity of cells of the mononuclear phagocyte system, localized in different tissues, in their interaction with y. pestis. the macrophage populations under study have been found to be heterogeneous in their phagocytic activity with respect to y. pestis. the digestive activity of alveolar macrophages is considerably lower than that of macrophages localized in other tissues. macrophages obtained from different tissue are heterogeneous also in the ... | 1990 | 2097850 |
| [y. pestis phage of a new serovar]. | phage ii, isolated from y. pestis strain 2247 obtained from a desert focus in central asia, has been studied. the phage is classified with moderate phages and essentially differs from moderate phages of serovar 2. the sources of isolation, high specificity and the absence of common serological features with presently known y. pestis phages of serovars 1 and 2 permit the classification of this phage with new serovar 3 of y. pestis phages. | 1990 | 2097853 |
| [the lytic activity of yersinia pestis phage p 3d serovar]. | the lytic activity of plague phage ii, serovar 3, with respect to 1,800 bacterial strains has been studied: 760 yersinia pestis strains, 262 y. pseudotuberculosis strains, 252 y. enterocolitica strains, 166 escherichia coli strains, 90 shigella strains and 270 strains of other species. the phage has been found to lyse 81.8% of y. pestis strains, 1 y. pseudotuberculosis strain and 1 y. enterocolitica strain. the representatives of other 19 bacterial species have proved to be resistant to the phag ... | 1990 | 2099066 |
| [a polarographic method in assessing the cultural properties of the ev vaccinal strain]. | the kinetic and regulatory characteristics of the oxidation metabolism of glucose, whose differences in collection cultures correspond to their capacity for growth in fluid culture medium under the conditions of aeration and the periodic addition of glucose, have been proposed on the basis of the polarographic method used for the registration of microbial breath in vaccine strain ev. pronounced metabolic disturbances resulting from the prolonged storage of the stock culture and working standards ... | 1990 | 2099067 |
| [the use of the macrophage disappearance reaction for detecting delayed hypersensitivity to yersinia pestis antigens]. | the possibility of using the reaction of macrophage disappearance (rmd) for the detection of delayed hypersensitivity (dh) to y. pestis has been studied. as the result of these studies, rmd has been found suitable, in principle, for use in the quantitative evaluation of dh to y. pestis. high sensitivity and specificity of this reaction have been established. the presence of dh in the process of the formation of immunity after immunization with y. pestis antigen fia has been shown. rmd can be obs ... | 1990 | 2099076 |
| [the role of macrophages in the immunogenesis of plague]. | | 1990 | 2099079 |
| serologic survey of selected zoonotic disease agents in black-tailed jack rabbits from western texas. | a serologic survey for the agents of rocky mountain spotted fever (rmsf) (rickettsia rickettsii), borrelia spp. including the causative agent for lyme disease (borrelia burgdorferi), and plague (yersinia pestis) was conducted on blood samples collected from 30 and 46 black-tailed jack rabbits (lepus californicus) from an urban environment in lubbock, texas (usa) during winter 1987 and the following spring 1988, respectively. antibody titers to the agents of rmsf and borreliosis were detected in ... | 1990 | 2106044 |
| cloning, sequence analysis, and expression of genes encoding xylan-degrading enzymes from the thermophile "caldocellum saccharolyticum". | a lambda recombinant bacteriophage coding for xylanase and beta-xylosidase activity has been isolated from a genomic library of the extremely thermophilic anaerobe "caldocellum saccharolyticum." partial sau3ai fragments of the lambda recombinant dna were ligated into pbr322. a recombinant plasmid with an insertion of ca. 7 kilobases of thermophilic dna expressing both enzymatic activities was isolated. the location of the genes has been established by analyzing deletion derivatives, and the dna ... | 1990 | 2111111 |
| imported bubonic plague--district of columbia. | | 1990 | 2123285 |
| secretion of yop proteins by yersiniae. | upon incubation at 37 degrees c in the absence of ca2+ ions, pathogenic strains of the genus yersinia cease growing and produce large amounts of a series of plasmid-encoded proteins involved in pathogenicity. these proteins, called yops (for yersinia outer membrane proteins), are detected in both the outer membrane fraction and the culture supernatant. we present here the nucleotide sequence of genes yop20 and yop25 from yersinia enterocolitica o:9. protein yop25 is very similar to yope, the cor ... | 1990 | 2129533 |
| association-dissociation processes and supermolecular organisation of the capsule antigen (protein f1) of yersinia pestis. | the association-dissociation processes involving the capsule antigen of yersinia pestis were investigated. in aqueous salt solutions the material of the capsule (protein f1) exists in the form of associated species containing identical monomeric protein subunits. brief heating (100 degrees c, 3 min) of f1 dissolved in buffered salt solutions at phs between 4.4 and 7.5 leads to dissociation of the antigen into oligomers which reassociate at room temperature into aggregates of high molecular mass. ... | 1990 | 2133058 |
| [effect of ascorbic acid for periodontal ligament fibroblast of human deciduous and permanent teeth]. | ascorbic acid (asa) plays an important role in the formation of collagen in the periodontal ligaments. however, the biochemical role of asa on the cell metabolism of periodontal ligaments remains undeveloped. this study attempts to explore the effect of asa and l-ascorbic acid-2-phosphate (asa-p) on the cell proliferation and differentiation, and the activity of cell attachment and spreading of conditioned medium (cm) prepared from human fibroblasts derived from the periodontal ligaments of deci ... | 1990 | 2134885 |
| [effect of ascorbic acid for periodontal ligament fibroblast of human deciduous and permanent teeth]. | ascorbic acid (asa) plays an important role in the formation of collagen in the periodontal ligaments. however, the biochemical role of asa on the cell metabolism of periodontal ligaments remains undeveloped. this study attempts to explore the effect of asa and l-ascorbic acid-2-phosphate (asa-p) on the cell proliferation and differentiation, and the activity of cell attachment and spreading of conditioned medium (cm) prepared from human fibroblasts derived from the periodontal ligaments of deci ... | 1990 | 2134885 |
| oxytocin, vasoactive-intestinal peptide, and serotonin regulate the mating-induced surges of prolactin secretion in the rat. | in female rats the mating stimulus induces a bimodal pattern of prl secretion. a surge of prl occurs at approximately 0300 h, called the nocturnal surge (n). another surge occurs at 1700 h on the same day, called the diurnal surge (d). by lowering dopaminergic tone pharmacologically, we have recently demonstrated the existence of an endogenous rhythm stimulatory to prl secretion in female rats. the periods of this stimulatory influence coincide with the periods of the n and d surges of prl that ... | 1990 | 2136724 |
| [the expression of fc gamma receptors on the surface of macrophages activated by a vaccinal strain of yersinia pestis]. | the expression of fc gamma r on the surface of macrophages in the process of antiplague immunity formation is analyzed. the stud is performed on the alveolar and peritoneal macrophages obtained from intact and immunized guinea pigs in different periods after vaccination (the 1st, 7th, 14th and 21st day). it is established that during the formation of the antiplague immunity there occurs activation of macrophages which is accompanied by an increase of the fc gamma r expression on the outer surfac ... | 1990 | 2142978 |
| [the role of t-suppressors in the formation of plague immunity in mice]. | antiplague immunization of mice causes an increase in the number of t-suppressors in their thymus and spleen; this increase is especially pronounced after injection of a low-immunogenic dose of the vaccine strain. t-suppressors specific to yersinia pestis antigens were detected in the thymus on day 3 after a single injection and on day 14 after two injections of the vaccine strain. | 1990 | 2143614 |
| [the epizootiological preconditions and clinico-epidemiological characteristics of a case of plague in 1988 in the settlement of kazbek, guryev province]. | | 1990 | 2146843 |
| [the sensitivity of yersinia to bacteriophage mu]. | various representatives of the genus yersinia were found to differ in their sensitivity to the lytic action of bacteriophage mu cts62, which could serve as an auxiliary test for the differentiation of y. pestis and y. pseudotuberculosis. among the strains under study, the causative agents of plague (34 strains) were sensitive to phage mu cts62, while the causative agents of enteric yersiniosis (42 strains) and pseudotuberculosis (73 strains), except 3 strains with the properties of y. pestis, we ... | 1990 | 2146845 |
| delay of puberty and impairment of growth in female rats given a non competitive antagonist of nmda receptors. | reportedly, excitatory amino acids are involved in the control of gonadotropin secretion of rats and non-human primates. the aim of this study was to investigate the effect of chronic blockade of nmda (n-methyl-d-aspartic acid) receptors by the non competitive receptor antagonist mk-801 on gonadotropin secretion and the onset of puberty in female rats. moreover, since in humans alterations of the timing of puberty frequently coexist with disturbances of body growth, suggesting a common etiology ... | 1990 | 2147050 |
| membrane potential and na(+)-k+ pump activity modulate resting and bradykinin-stimulated changes in cytosolic free calcium in cultured endothelial cells from bovine atria. | the effects of membrane potential on resting and bradykinin-stimulated changes in [ca2+]i were measured in fura-2 loaded cultured endothelial cells from bovine atria by spectrofluorimetry. the basal and bradykinin-stimulated release of endothelium-derived relaxing factor, monitored by bioassay methods, were dependent on extracellular ca2+. similarly, the plateau phase of the biphasic [ca2+]i response to bradykinin stimulation exhibited a dependence on extracellular ca2+, whereas the initial tran ... | 1990 | 2154452 |
| simultaneous primary infection with hiv and cmv leading to severe pancytopenia, hepatitis, nephritis, perimyocarditis, myositis, and alopecia totalis. | simultaneous primary infection with hiv and cmv in an 18-year-old woman led to an acute cytotoxic reaction, manifesting as pancytopenia, hepatitis, nephritis, perimyocarditis, and myositis. within 14 days parameters indicating acute cell damage reverted to normal. two weeks later transient alopecia totalis developed. initially, hiv-antigen but no hiv antibodies were present. within 3 weeks hiv-igg antibodies appeared while hiv antigen disappeared. anti-cmv-igm was clearly and anti-cmv-igg questi ... | 1990 | 2156107 |
| [protein phosphorylation in the causative agent of plague]. | the phenomenon of the reversible phosphorylation of proteins has been discovered in y. pestis cells. eight proteins with a molecular weight of 30-80 kilodaltons have been found capable of phosphorylation. the intensity of phosphorylation has been found to be influenced by the temperature of cultivation and the composition of the incubation medium. this newly found phenomenon of the chemical modification of proteins is supposed to play a certain role in the organization of rapid responses of the ... | 1990 | 2158704 |
| the lcre gene is part of an operon in the lcr region of yersinia enterocolitica o:3. | the low-calcium response (lcr) region of the virulence plasmid of yersinia pestis, yersinia pseudotuberculosis, and yersinia enterocolitica has been associated with calcium-dependent growth of bacteria. mutations in the previously identified lcre locus within the lcr region lack the repressor control of production of the lcr specific proteins, yersinia outer membrane proteins (yops) and v and w antigens. we sequenced a 3.3-kilobase-pair bamhi-clai fragment of the lcre locus of pyvo3, the virulen ... | 1990 | 2160939 |
| yersinia pestis ph 6 antigen: genetic, biochemical, and virulence characterization of a protein involved in the pathogenesis of bubonic plague. | we studied a protein antigen, designated ph 6 ag, that has the same regulation of expression as the previously described yersinia pestis ph 6 ag. monospecific antiserum to this antigen recognized several proteins, ranging from 15 to over 75 kilodaltons (kda), which were strongly expressed when y. pestis was cultivated at 37 degrees c and ph 6 but were expressed weakly, if at all, at 37 degrees c and ph 8 and at 26 degrees c. the antigen appeared to be composed of aggregates of a 15-kda subunit. ... | 1990 | 2164509 |
| [the use of mini-mu-replicons for cloning of various structural genes of yersinia pestis]. | the possibility to clone the structural leu gene of yersinia pestis in vivo using the mini-mu bacteriophages with the inserted plasmid replicones has been demonstrated. the e. coli k12 transductants having obtained the leu(+)-marker within the cloned 4.8-21 kb fragments stably inherited the leu-gene within the autonomous mini-mu replicones. the possibility to clone other yersinia pestis genes by the same technique has been demonstrated. | 1990 | 2166239 |
| past and future of neuropsychopharmacology. | the advent of what is called the chemotherapy of mental diseases goes back to the early fifties, when a series of clinical observations led medical research to reconsider this field, that at the time was not particularly developed. the use of chlorpromazine and of reserpine in the therapy of some psychotic syndromes dates back to that time. a few years later meprobamate was introduced and proved active against anxiety. the success obtained with these drugs was followed by a flourishing of resear ... | 1990 | 2168139 |
| kinetics of the reaction of prostaglandin h synthase compound ii with ascorbic acid. | the reduction of prostaglandin h synthase compound ii by ascorbic acid in the presence of diethyldithiocarbamate was studied in 0.1 m phosphate buffer (ph 8.0) at 4.0 +/- 0.5 degrees c, by rapid scan spectrometry and transient state kinetics. a saturation effect and nonzero intercept were observed in the plot of pseudo-first-order rate constant versus ascorbic acid concentration. the saturation behavior suggests formation of a complex between prostaglandin h synthase compound ii and ascorbic aci ... | 1990 | 2168160 |
| identification of genes affecting production of the adhesion organelle of caulobacter crescentus cb2. | transposon (tn5) mutagenesis was used to identify regions in the genome involved with production, regulation, or attachment to the cell surface of the adhesive holdfast of the freshwater bacterium caulobacter crescentus cb2. a total of 12,000 independently selected transposon insertion mutants were screened for defects in adhesion to cellulose acetate; 77 mutants were detected and examined by southern blot hybridization mapping methods and pulsed-field gel electrophoresis. ten unique sites of tn ... | 1990 | 2168382 |
| [control of interstitial pneumonia with the application of immune transfer]. | allogeneic bone marrow transplantation (bmt) has been used successfully to treat patients with hematological malignancies. however, interstitial pneumonia has remained a major complication following bmt. we investigated the possibility of immune transfer in recipients treated with bmt from immunized donors. bone marrow donors were vaccinated with tetanus toxoid (tt) before marrow harvest. after bmt, serum igg anti-tt antibody titer and in vitro igg anti-tt antibody production in recipients were ... | 1990 | 2168493 |
| determination of bhv1 specific immune reactivity in naturally infected and vaccinated animals by lymphocyte proliferation assays. | the in vitro bhv1-specific lymphocyte stimulation assay was used to investigate immune reactivity of cattle after natural infection or vaccination with bhv1. proliferative responses to live virus were shown in tests with peripheral blood lymphocytes of seropositive field virus-infected animals and of vaccinated animals. nineteen out of 36 seropositive field virus-infected animals did not show in vitro responses. nine out of 12 animals showed, at least transient, responsiveness after vaccination. ... | 1990 | 2168602 |
| protective effect of inactivated pasteurella haemolytica bacterin challenged in bovine herpesvirus-1 experimentally infected calves. | formalin-inactivated and sonicated pasteurella haemolytica bacterins were prepared from 1 h cultures of bacterial pellets in rpmi-1640 medium containing 7% fetal calf serum. the bacterial pellets were obtained from logarithmic phase growth of the organism by centrifugation. the protective effect of the vaccine was evaluated in 43 specific-pathogen-free hereford crossbred calves and yearlings in three experiments. cattle were either single vaccinated or boosted via three routes; intratracheally ( ... | 1990 | 2168606 |
| mechanisms underlying the stimulation of pth release by gppnhp in permeabilized bovine parathyroid cells. | we examined changes in camp and inositol phosphate metabolism to assess the contribution of the guanine nucleotide regulatory (g) protein(s) regulating adenylate cyclase and phospholipase c in mediating the stimulatory effects of gppnhp on pth release from permeabilized bovine parathyroid cells. to examine the role of gs, the g protein stimulating adenylate cyclase, and camp on pth release, permeabilized cells were incubated with either gppnhp or isoproterenol, and the effects of these agents on ... | 1990 | 2168660 |
| effect of particle size and temperature on the conformation and physiological behavior of apolipoprotein e bound to model lipoprotein particles. | the effect of particle size and structural order/disorder of the lipid domain on the conformation and physiological behavior of lipid-associated apolipoprotein e (apoe) was evaluated. circular dichroic (cd) spectra of apoe bound to large (lme) and small (sme) microemulsion particles, composed of dimyristoylphosphatidylcholine (dmpc) and cholesteryl oleate (co), and to dmpc disks revealed that at 4 degrees c, where all of the lipid constituents were in an ordered state, apoe bound to lme displaye ... | 1990 | 2168737 |
| characterization of vasoactive intestinal peptide receptors in retina. | vasoactive intestinal peptide (vip) is a neuropeptide having a wide range of effects on a large number of tissues. to gain insight into the role vip plays in retinal function, vip receptors in bovine retinal membranes were analyzed in competition binding assays and by affinity labeling studies and compared to vip receptors in rat liver membranes. in both membrane preparations, high affinity vip binding sites (kd approximately 1 nm) were detected. secretin and glucagon, each having close structur ... | 1990 | 2169429 |
| osteoblasts display receptors for and responses to leukemia-inhibitory factor. | specific binding of leukemia-inhibitory factor (lif) to osteoblasts, but not multinucleated osteoclasts, was demonstrated by receptor autoradiography by using cells isolated from newborn rat long bones. the clonal rat osteogenic sarcoma cells, umr 106-06, which have several phenotypic properties of osteoblasts, expressed 300 lif receptors per cell, with an apparent kd of 60 pm. treatment of calvarial osteoblasts or umr 106-01 cells with lif resulted in a dose-dependent inhibition of plasminogen ... | 1990 | 2170427 |
| biphasic effects of polarizing current on adenosine-sensitive generation of cyclic amp in rat cerebral cortex. | cyclic amp accumulation elicited by adenosine was investigated in cortical slices of rats following the application of a weak anodal direct current (anodal polarization) to the unilateral sensorimotor cortex. anodal polarization with 3.0 microa for 30 min caused an increase in the adenosine-elicited accumulation of cyclic amp in the polarized cortex, in which case the increase in the polarized cortical region was highlighted by repeated applications of the currents. polarization with 0.3 microa ... | 1990 | 2173816 |
| detection of bovine viral diarrhea virus in serum from cattle by dot blot hybridization assay. | a dot blot hybridization assay was developed for use as a rapid screening test to detect bovine viral diarrhea virus (bvdv) in serum from infected cattle. a 1.1. kilobase cdna, prepared from the bvdv genome, was molecularly cloned and used in this study. insert cdna was removed from the puc9 plasmid vector by pst-i restriction endonuclease digestion and purified from plasmid dna by agarose electrophoresis and electroelution. the hybridization probe was prepared by nick translation in the presenc ... | 1990 | 2175527 |
| [a cyclic 3',5'-adenosine monophosphate-binding protein in the causative agent of plague]. | camp-binding protein was isolated from the plaque agent and purified to the homogeneous state. purification process included filtration of the initial preparation through the membrane able to transmit particles with mol. weight to 300,000 da, chromatography on cellulose "de-52" and biogel htp. the protein homogeneity was confirmed by electrophoresis in polyacrylamide gel and precipitation with commercial plague agglutinating serum. the protein with mol. weight of 180,000 da consisted of two iden ... | 1990 | 2177132 |
| [the role of is-elements of yersinia pestis (lehmann, neumann) in the emergence of calcium-independent mutations]. | calcium independent mutants of two yersinia pestis strains were studied. insertions of is100 element at three different sites of plasmid pcad within calcium dependence region were detected in y. pestis ev, as well as two extensive deletions covering the whole region. it was shown that is100 carries no hindiii sites. novel is element of y. pestis designated is101 was discovered in strain 358, in addition to is100. it is distinguished by a slightly smaller size, hindiii site presence and high spec ... | 1990 | 2178143 |
| [function of large plasmids of the plague pathogen]. | function of the largest plasmid of yersinia pestis was studied. assay of four strains of highly virulent y. pestis isolated from different natural sources demonstrated that the characters of endotoxin production, sugar and alcohol fermentation, nitrate reduction as well as requirement in nutrients are mediated by no y. pestis plasmids. on the contrary, fi and fii antigens are determined by the largest plasmid in some strains and are chromosome-mediated in others. it may well be that the genes fo ... | 1990 | 2178144 |
| [the discovery of yersinia pestis]. | | 1990 | 2188341 |
| clinical manifestations of hiv infection, including persistent generalized lymphadenopathy and aids-related complex. | the ability to recognize disease related to the human immunodeficiency virus (hiv) and subsequent acquired immunodeficiency syndrome (aids) has improved in recent years with refinement of laboratory techniques. because of this progress, several clinical conditions can now be identified as "pre-aids" syndromes. these include the persistent generalized lymphadenopathy syndrome, immune thrombocytopenic purpura, the wasting syndrome, and certain predominantly neurologic presentations. all are charac ... | 1990 | 2193949 |
| [the ability of flea species on the common vole from mountainous dagestan to transmit and preserve the causative agent of plague]. | the infection ability and terms of preservation of plague microbe in fleas of common vole from dagestan high-mountain plague focus (frontopsylla causasica, megabothris turbidus, ctenophthalmus intermedius and amphipsylla rossica) was studied experimentally. block formation and transmission of the infection by f. caucasica and m. turbidus was observed. the transmission of plague microbe by ct. intermedius fleas was first carried out. these species of fleas preserve the infection for a long time. ... | 1990 | 2195439 |
| [the efficiency of rhadinopsylla rothschildi and r. dahurica fleas as vectors of the causative agent of plague in a transbaikal natural focus]. | experiments have shown that a block of proventriculus arises in 2.1 to 12.5% of infected fleas of r. rothschildi and in 7.2 to 10.5% of r. dahurica. these fleas transmit the plague agent to different animals (brandt's vole, narrow-skulled vole, dahurian suslik). the plague microbe is preserved in the organism of infected insects till the end of the experiment, 74 and 24 days respectively. therefore, the fleas can play a part in the maintenance of plague epizootics in the transbaikal natural nidu ... | 1990 | 2195440 |
| cloning of the yeast sfl2 gene: its disruption results in pleiotropic phenotypes characteristic for tup1 mutants. | we have identified a yeast gene, sfl2 (suppressor gene for flocculation), which complemented a newly isolated sfl2 mutant. this mutation causes asexual cell aggregation. the strain bearing the sfl2 gene disruption exhibited pleiotropic phenotypes characteristic for tup1 mutants. physical mapping and complementation analysis suggested that the cloned sfl2 gene is identical to the tup1 gene. the sfl2 gene encodes a 669-amino acid protein which has domains rich in glutamine, as does the ssn6 protei ... | 1990 | 2197185 |
| [the isolation and characteristics of yersinia pestis membranes]. | a method for fractionation of membrane structures of yersinia pestis is developed. it involves the following basic stages: the cultivation of bacteria in a liquid nutrient medium, mechanical destruction from the solid state in the x-press or ultrasound treatment of the suspension, subsequent two-stage centrifugation in the step (70-15%) and linear (70-45%) gradients of the sucrose density, collection of fractions and their storage. the method makes it possible to separate rapidly and efficiently ... | 1990 | 2198438 |
| nucleotide sequence of yst, the yersinia enterocolitica gene encoding the heat-stable enterotoxin, and prevalence of the gene among pathogenic and nonpathogenic yersiniae. | the gene encoding the heat-stable enterotoxin (yst) was cloned from the chromosome of yersinia enterocolitica w1024 (serotype o:9), and the nucleotide sequence was determined. the yst gene encodes a 71-amino-acid polypeptide. the c-terminal 30 amino acids of the predicted protein exactly correspond to the amino acid sequence of the toxin extracted from culture supernatants (t. takao, n. tominaga, and y. shimonishi, biochem. biophys. res. commun. 125:845-851, 1984). the n-terminal 18 amino acids ... | 1990 | 2201642 |
| in vitro activity of ljc10,627, a new carbapenem antibiotic with high stability to dehydropeptidase i. | the in vitro activity of ljc10,627, a new carbapenem, was compared with those of imipenem and ceftazidime. ljc10,627 had broad-spectrum activity against gram-positive and gram-negative clinical isolates. the mics of this compound for 90% of members of the family enterobacteriaceae tested (mic90s), including strains resistant to ceftazidime, ranged from 0.1 to 25 micrograms/ml. ljc10,627 inhibited pseudomonas aeruginosa at an mic90 of 3.13 micrograms/ml; it thus was twofold more active than imipe ... | 1990 | 2203313 |
| identification and cloning of a hemin storage locus involved in the pigmentation phenotype of yersinia pestis. | the temperature-dependent absorption of sufficient exogenous hemin or congo red to form pigmented colonies of yersinia pestis has been termed the pigmentation phenotype (pgm+). spontaneous mutation to a pgm- phenotype results in the loss of a number of divergent physiological characteristics, including the ability to store hemin and to bind congo red at 26 degrees c. in this study, we generated and isolated transposon insertion mutants that are hemin storage negative (hms-) and therefore unable ... | 1990 | 2211518 |
| effect of magnesium lithospermate b on urinary prostaglandins in rats with renal failure. | urinary excretion of prostaglandin e2 showed a significant increase following administration of magnesium lithospermate b [1] in rats with renal failure. in contrast, that of thromboxane b2 showed a significant decrease, indicating the improvement of renal failure. | 1990 | 2213036 |
| in-vitro mutagenesis of the bovine growth hormone gene. | the biological activities of bovine growth hormone (bgh) were studied in a transgenic mouse model system. the following experimental design was used: (1) in-vitro mutagenesis of the bgh gene; (2) expression of the mutated gene in cultured mouse cells under transcriptional regulation of the mouse metallothionein i promoter; (3) binding studies of the mutated and wild-type protein to mouse liver membrane preparations; (4) generation of transgenic mice which express the mutant hormone; and (5) grow ... | 1990 | 2213712 |
| in-vitro mutagenesis of the bovine growth hormone gene. | the biological activities of bovine growth hormone (bgh) were studied in a transgenic mouse model system. the following experimental design was used: (1) in-vitro mutagenesis of the bgh gene; (2) expression of the mutated gene in cultured mouse cells under transcriptional regulation of the mouse metallothionein i promoter; (3) binding studies of the mutated and wild-type protein to mouse liver membrane preparations; (4) generation of transgenic mice which express the mutant hormone; and (5) grow ... | 1990 | 2213712 |
| strain specific variation of outer membrane proteins of wild yersinia pestis strains subjected to different growth temperatures. | three yersinia pestis strains isolated from humans and one laboratory strain (ev76) were grown in rich media at 28 degrees c and 37 degrees c and their outer membrane protein composition compared by sodium dodecyl sulphate polyacrylamide gel electrophoresis (sds-page). several proteins with molecular weights ranging from 34 kda to 71 kda were observed to change in relative abundance in samples grown at different temperatures. at least seven y. pestis outer membrane proteins showed a temperature- ... | 1990 | 2215220 |
| [the epizootiological significance of flea accumulation in aggregations of the female long-tailed suslik in the tuva plague focus]. | the formation of aggregations of related females is a peculiarity of the intrapopulational organization of long-tailed suslik that results in the accumulation of citellophilus tesquorum, the main vector and keeper of the plague microbe in the tuva plague nidus. the plague agent is adapted to the existence on the territory occupied by aggregations of females that manifests itself in the delay of the beginning and prolixity of block-formation periods in fleas. the transfer of the agent from one pl ... | 1990 | 2216531 |
| the continuous decrease in the number of sspe annual cases ten years after compulsory anti-measles immunization. | the record of sspe cases diagnosed immunochemically and serologically in our laboratory, standing for about 60% of the total new cases reported in our country, shows a significant decrease in the incidence in 1988-89 (from 5.21 new cases per year per million total population in 1987 to 1.82 cases in 1988). in 85% of the patients, sspe onset occurred at the age of 10 years or more, suggesting the possibility of a primary measles infection before anti-measles immunization became compulsory. high s ... | 1990 | 2223653 |
| the continuous decrease in the number of sspe annual cases ten years after compulsory anti-measles immunization. | the record of sspe cases diagnosed immunochemically and serologically in our laboratory, standing for about 60% of the total new cases reported in our country, shows a significant decrease in the incidence in 1988-89 (from 5.21 new cases per year per million total population in 1987 to 1.82 cases in 1988). in 85% of the patients, sspe onset occurred at the age of 10 years or more, suggesting the possibility of a primary measles infection before anti-measles immunization became compulsory. high s ... | 1990 | 2223653 |
| dietary animal proteins and cholesterol metabolism in rabbits. | the effect in rabbits of giving isonitrogenous purified diets containing casein, ovalbumin, fish protein, milk-whey protein and soya-bean protein were compared. the diets were balanced for cholesterol and for the amount and type of fat. when incorporated into low-cholesterol diets (0.08 g cholesterol/kg), casein, ovalbumin and soya-bean protein produced similar levels of serum cholesterol. with a high background of dietary cholesterol (1.5 g/kg), serum cholesterol concentrations increased with s ... | 1990 | 2223748 |
| dietary animal proteins and cholesterol metabolism in rabbits. | the effect in rabbits of giving isonitrogenous purified diets containing casein, ovalbumin, fish protein, milk-whey protein and soya-bean protein were compared. the diets were balanced for cholesterol and for the amount and type of fat. when incorporated into low-cholesterol diets (0.08 g cholesterol/kg), casein, ovalbumin and soya-bean protein produced similar levels of serum cholesterol. with a high background of dietary cholesterol (1.5 g/kg), serum cholesterol concentrations increased with s ... | 1990 | 2223748 |
| chloroplast glyceraldehyde-3-phosphate dehydrogenase (nadp): amino acid sequence of the subunits from isoenzyme i and structural relationship with isoenzyme ii. | the structural relationship between isoenzymes i and ii of chloroplast glyceraldehyde-3-phosphate dehydrogenase (d-glyceraldehyde-3-phosphate: nadp+ oxidoreductase (phosphorylating) ec 1.2.1.13) has been established at the protein level. the complete primary structure of subunits a and b of glyceraldehyde-3-phosphate dehydrogenase i from spinacia oleracea has been determined by sequence analysis of the corresponding tryptic peptides, aligned by fragments derived from cyanogen bromide and staphyl ... | 1990 | 2223845 |
| [plasmid dna transformation of yersinia pseudotuberculosis by electroporation]. | rendering cells permeable to dna molecules, electroporation involves the application of high intensity electric fields of short duration to reversibly change the biomembranes, which has been used successfully in some species of both gram negative and positive bacteria. we first reported the electro-transformation technics of yersinia pseudotuberculosis. the plasmid pjgx20 was constructed by cloning the 9.5 kb plasmid encoding pesticin into pst i site of pbr328. transformation efficiency of 103 t ... | 1990 | 2225008 |
| new refractive method for laser thermal keratoplasty with the co:mgf2 laser. | we have observed corneal curvature changes from laser thermal keratoplasty with a co:mgf2 laser. we studied corneal curvature changes in rabbits and have identified specific treatment patterns and laser parameters that can correct myopia and astigmatism. these corneal changes, some as large as 8 diopters, have been stable for at least one year, and slitlamp examination demonstrates clear central corneas with normal appearance. | 1990 | 2231379 |
| nitrate reductases of escherichia coli: sequence of the second nitrate reductase and comparison with that encoded by the narghji operon. | the structural genes for nrz, the second nitrate reductase of escherichia coli, have been sequenced. they are organized in a transcription unit, narzywv, encoding four subunits, narz, nary, narw and narv. the transcription unit is homologous (73% identity) to the narghji operon which encodes the genes for nra, the better characterized nitrate reductase of this organism. the level of homology between the corresponding polypeptides ranges from 69% for the narw/narj pair to 86% for the narv/nari pa ... | 1990 | 2233673 |
| [isolation of transmissible cointegrates of yersinia pestis plasmids pyv and pyt with the plasmid rp4::mu cts 62, incp1]. | the transmissible cointegrates of the yersinia pestis plasmids pyv and pyt with the broad host range plasmid rp4::mu cts62 of the incompatibility group incp have been constructed by the in vivo recombination. the cointegrative plasmid pkr14 (pyv76 omega rp4::mu cts62) conferred on the transconjugants the properties of ca2(+)-dependence at 37 degrees c, v-antigen synthesis, rp4 plasmid markers (apr, kmr, tcr), immunity to the lysis by the bacteriophage mu cts62 and incompatibility with the homolo ... | 1990 | 2233780 |
| [expression of yersinia pestis antigens encoded by the ca2+-dependence plasmid]. | antigens coded by the ca2(+)-dependance plasmid were found in the cultural medium, cytoplasm and outer membranes of the three monoplasmid (pcadv) strains of yersinia pestis with the different basic properties. the presence of 20 mm of mg2+ at least in the medium is necessary for optimal expression of these proteins. the existence of strain differences in the bacterial cells reaction to temperature, cultivation medium has been demonstrated. no difference in the pcad-dependent proteins was found i ... | 1990 | 2233781 |
| [relation between the yersinia phage and bacteriophages isolated from the environment]. | the bacteriophage designated rd2 has been isolated from the sewage in rostov-on-don city and studied. the morphology of bacteriophage particles and the biological properties of the bacteriophage make it related to the plague bacteriophage isolated by d'errel. the molecular masses of the compared bacteriophages are almost identical being 26.4 +/- 0.4 md for rd2 and 24.7 +/- 0.2 md for d'errel bacteriophage. the dnas of the bacteriophages share 80% of homology and possess 15 nonhomologous regions ... | 1990 | 2233785 |