| studies on the binding of 5,5-diphenyl-hydantoin to nucleic acids in vitro and to rat brain subcellular fractions in vitro and in vivo. | the binding of 5,5-diphenylhydantoin (dph) to nucleic acids (bovine brain rna, rat liver ribosomal and trna, torula utilis rna, and calf thymus and escherichia coli dna was studied using ultraviolet spectroscopy, gel chromatography and thermal transition profiles. within the sensitivity of these methods, it was found that there is essentially little or no interaction between dph and nucleic acids in vitro as has been reported previously. little, if any evidence of dph intercalation with dna was ... | 1976 | 1255490 |
| creation and characterization of temperature-sensitive mutants of the lck tyrosine protein kinase. | temperature-sensitive mutants of the lck tyrosine protein kinase were created by the introduction of mutations known to cause temperature sensitivity of the v-src tyrosine protein kinase of rous sarcoma virus. p56lck activated by mutation of the regulatory site of tyrosine phosphorylation, tyr-505, to phe transforms fibroblasts in culture. mutations identical to those responsible for the temperature-sensitive phenotypes of the tsny68 and tsny72-4 v-src mutants rendered this activated lck gene te ... | 1992 | 1279202 |
| identification of inducible calmodulin-dependent nitric oxide synthase in the liver of rats. | a calmodulin-dependent nitric oxide synthase was significantly induced in the liver of rats treated intravenously with heat-killed propionibacterium acnes and 5 days later with escherichia coli lipopolysaccharide. the apparent calmodulin-dependent and -independent isozymes were separated by mono q column chromatography after their partial purification by 2',5'-adp-agarose affinity chromatography. both enzymes had a molecular weight of 125,000 as determined by sds-polyacrylamide gel electrophores ... | 1992 | 1281157 |
| [the ultrastructural changes in the glomeruli and juxtaglomerular apparatus at different periods of endotoxic shock]. | it is shown that after endotoxin injection the ultrastructural changes in the glomeruli can favour development of the acute renal insufficiency. in the initial and intermediate periods of the endotoxin shock the granular and agranular forms of juxtaglomerular cells hyperfunction, respectively, are revealed as well as an increase of renin activity in plasma. at the stage of the late endotoxemia ultrastructural alterations are stabilized. the juxtaglomerular cells synthesize and accumulate secreto ... | 1992 | 1286692 |
| the biological interaction of cis- and trans-urocanic acid and dna. | the potential for the cis and trans isomers of urocanic acid to produce dna damage was measured by assays for dna binding (32p-postlabeling assay), for induction of dna repair (unscheduled dna synthesis assay) and induction of mutations (salmonella typhimurium and escherichia coli plate-incorporation assays). these assays did not detect any evidence of a direct effect of either isomer of urocanic acid on dna over a wide range of concentrations. these results suggest that neither isomer of urocan ... | 1992 | 1300140 |
| introduction of a foreign gene (escherichia coli lacz) into rat neostriatal neurons using herpes simplex virus mutants: a light and electron microscopic study. | introducing genes into adult neurons in vivo may be a useful experimental tool for studying and modifying neuronal function. in this study two herpes simplex virus type 1 (hsv-1) mutants were used to examine the capability of different types of neostriatal neurons to express a foreign gene introduced through viral infection. in these hsv-1 mutants (7134 and rh105) the escherichia coli gene, lacz, under the control of viral promoters active during the early phase of infection, was substituted for ... | 1992 | 1311266 |
| production and characterization of recombinant insulin-like growth factor-i (igf-i) and potent analogues of igf-i, with gly or arg substituted for glu3, following their expression in escherichia coli as fusion proteins. | the development of an efficient expression system for insulin-like growth factor-i (igf-i) in escherichia coli as a fusion protein is described. the fusion protein consists of an n-terminal extension made up of the first 46 amino acids of methionyl porcine gh ([met1]-pgh) followed by the dipeptide val-asn. the latter two residues provide a unique hydroxylamine-sensitive link between [met1]-pgh(1-46) and the n-terminal gly of igf-i. downstream processing of the fusion proteins involved isolation ... | 1992 | 1311930 |
| atriopeptins and escherichia coli enterotoxin sta have different sites of action in mammalian intestine. | studies with escherichia coli-induced heat-stable enterotoxin (sta), an activator of intestinal particulate guanylate cyclase, have established an independent role for cyclic guanosine monophosphate (cgmp) as an intracellular mediator of intestinal salt and water secretion. the present study addressed whether atriopeptins (aps), known activators of particulate guanylate cyclase in other tissues, function as physiological agonists for cgmp-linked cl- secretion in intestine. aps, in contrast to st ... | 1992 | 1312972 |
| lysine 274 is essential for fructose 2,6-bisphosphate inhibition of fructose-1,6-bisphosphatase. | lysine 274 is conserved in all known fructose-1,6-bisphosphatase sequences. it has been implicated in substrate binding and/or catalysis on the basis of reactivity with pyridoxal phosphate as well as by x-ray crystallographic analysis. lys274 of rat liver fructose-1,6-bisphosphatase was mutated to alanine by the polymerase chain reaction, and the t7-rna polymerase-transcribed construct containing the mutant sequence was expressed in escherichia coli. the mutant and wild-type forms of the enzyme ... | 1992 | 1313010 |
| glu327 is part of a catalytic triad in rat liver fructose-2,6-bisphosphatase. | the fructose-2,6-bisphosphatase domain of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase has been shown to be structurally and functionally homologous to phosphoglycerate mutase. both enzymes catalyze their reactions via phosphoenzyme intermediates which utilize an active site histidine as a nucleophilic phosphoacceptor and another histidine as a proton donor to the leaving group. glu327 in the bisphosphatase domain of the rat liver bifunctional enzyme is conserved in all phosphoglycerate ... | 1992 | 1313012 |
| effect of endotoxin on circulating cyclic gmp in the rat. | the aim of this study was to investigate the possible use of plasmatic cyclic gmp as an index of l-arginine/nitric oxide (l-arg/no) pathway activation by e. coli endotoxin in vivo. endotoxin (20 mg kg-1 i.p.) caused a time-dependent increase in plasmatic cyclic gmp in anaesthetised rats which corresponded with the time course of l-arg/no pathway activation in aortas from the same rats, but was not prevented by a specific inhibitor of this pathway, ng-nitro-l-arginine methyl ester (1 mg kg-1 or 2 ... | 1992 | 1313373 |
| the effects of escherichia coli heat-stable enterotoxin in renal sodium tubular transport. | to compare the function of sodium transport between intestine and renal tubule, we studied the effect of e. coli sta enterotoxin and 8-bromo cyclic gmp in perfused rat kidneys. infusion of sta enterotoxin (0.017 and 0.1 micrograms/ml) caused a dose and time dependent decrease in total renal sodium tubular transport. the major site of sta effect was at the renal proximal tubule. similar to sta enterotoxin, 8-bromo cyclic gmp (10(-5) m) caused a significant decrease of fractional renal sodium prox ... | 1992 | 1315964 |
| cloning of a locus involved in streptococcus mutans intracellular polysaccharide accumulation and virulence testing of an intracellular polysaccharide-deficient mutant. | the streptococcal transposon tn916 (tcr) was used to isolate mutants of streptococcus mutans altered in glycogen accumulation to investigate whether glycogenlike intracellular polysaccharides (ips) play an important role in s. mutans-induced caries formation. s. mutans ua130 (serotype c) was transformed with the escherichia coli plasmid pam620 (tn916), and the resultant transposon libraries were screened for glycogen content by iodine staining. a transposon mutant, designated sms201, demonstrate ... | 1992 | 1322367 |
| organella-targeted expression of rat liver cytochrome p450c27 in yeast. genetically engineered alteration of mitochondrial p450 into a microsomal form creates a novel functional electron transport chain. | a modified rat cytochrome p450c27, whose mitochondrial targeting signal had been replaced by a possible microsomal targeting signal of bovine cytochrome p450c17, was expressed in yeast. the modified p450c27 hemoprotein was correctly localized on yeast microsomes and exhibited the p450c27-dependent monooxygenase activity by addition of bovine adrenodoxin (adx) and nadph-adrenodoxin reductase (adr). considering the previous observation that p450c27 with its own mitochondrial targeting signal was i ... | 1992 | 1322905 |
| molecular cloning of human macrophage capping protein cdna. a unique member of the gelsolin/villin family expressed primarily in macrophages. | macrophage capping protein (mcp) is a ca(2+)-sensitive protein which reversibly blocks the barbed ends of actin filaments but does not sever preformed actin filaments. the human cdna for mcp has been cloned and sequenced. the derived amino acid sequence predicts a polypeptide of 38.4 kda. human mcp expressed in escherichia coli using a pet12a vector was functionally identical to the native protein purified from rabbit alveolar macrophages with respect to ca2+ sensitivity and ability to block mon ... | 1992 | 1322908 |
| nucleoside diphosphokinase: a functional link between intermediary metabolism and nucleic acid synthesis. | | 1992 | 1323446 |
| glycoprotein receptors for a heat-stable enterotoxin (sth) produced by enterotoxigenic escherichia coli. | glycoprotein receptors for heat-stable enterotoxin sth of enterotoxigenic escherichia coli in the rat intestinal cell membrane were identified and characterized. incubation of rat intestinal cell membranes with radioiodinated n-5-azidonitrobenzoyl-sth[5-19] (125i-anb-sth[5-19]) followed by photolysis resulted in specific radiolabeling of two distinct proteins with m(r)s of 200,000 (designated str-200a and str-200b). str-200a was found to be composed of two molecules of a protein with an m(r) of ... | 1992 | 1328055 |
| antibodies against 70-kd heat shock cognate protein inhibit mediated nuclear import of karyophilic proteins. | previously, we found that anti-ddded antibodies strongly inhibited in vivo nuclear transport of nuclear proteins and that these antibodies recognized a protein of 69 kd (p69) from rat liver nuclear envelopes that showed specific binding activities to the nuclear location sequences (nlss) of nucleoplasmin and sv-40 large t-antigen. here we identified this protein as the 70-kd heat shock cognate protein (hsc70) based on its mass, isoelectric point, cellular localization, and partial amino acid seq ... | 1992 | 1332978 |
| rat liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase. properties of phospho- and dephospho- forms and of two mutants in which ser32 has been changed by site-directed mutagenesis. | the mechanism by which camp-dependent protein kinase-catalyzed phosphorylation modulates the activities of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase was examined after site-specific mutation of the camp-dependent phosphorylation site (ser32) to aspartic acid or alanine. the mutant and wild-type enzymes were overexpressed in escherichia coli in a rich medium to levels as high as 30 mg/liter and were then purified to homogeneity. the kinetic properties of the ser32-ala mutant were ident ... | 1992 | 1339450 |
| effects of thermostable escherichia coli enterotoxin peptide on the isolated rat kidney. | in order to compare the function of sodium transport between the intestine and renal tubule, we studied the effect of thermostable e. coli enterotoxin on rat kidneys. isolated kidneys from adult male hooded rats weighing 240-335 g were perfused with krebs-henseleit solution containing 60 mg/ml dialyzed bovine serum albumin. the effects of e. coli enterotoxin (sta; molecular weight approximately 2000; 18 amino acids with three disulfide bonds) were studied on glomerular filtration rate (gfr), net ... | 1992 | 1342238 |
| crf-dependent and crf-independent mechanisms involved in hypophysial-adrenal system activation by bacterial endotoxin. | the immune system and the hypothalamic-pituitary-adrenal (hpa) axis play important role in the overall inflammatory response. the mechanism through which lipopolysaccharide (lps, endotoxin) stimulates the hpa axis is not well understood. in order to clarify the role of hypophysiotropic peptides of paraventricular origin in the effect of lps on acth and corticosterone secretion, the effect of lps was studied on rats with lesions of hypothalamic paraventricular nucleus (pvn). it was shown that 90 ... | 1992 | 1343188 |
| protective effect of radio-detoxified endotoxin (tolerin) on the ultrastructure of pancreas in experimental endotoxin shock of rats. | the ultrastructural changes of pancreas exocrine cells were studied after the intravenous administration of endotoxin (lps) or radio-detoxified endotoxin (150 kgy 60co-gamma irradiated: rd-lps or tolerin). the lps (1 mg/rat) induces an autolytic destruction in the membranes of the mitochondria of the pancreas exocrine cells. the rd-lps given in similar dose does not produce any autolytic change. however, a small dose (100/micrograms/rat) of rd-lps (tolerin) as a pretreatment can protect the auto ... | 1992 | 1343463 |
| lipopolysaccharide stimulates phosphorylation of eukaryotic initiation factor-4f in macrophages and tumor necrosis factor participates in this event. | bacterial lipopolysaccharide (lps) produces rapid changes in macrophage protein synthesis and function. phosphorylation of the 25 kda mrna cap-binding protein (eif-4e) in model systems regulates the efficiency of protein synthesis. we report that both lps and tumor necrosis factor-alpha (tnf-alpha) stimulate phosphorylation of eif-4e and the p220 component of eif-4f in bone marrow-derived macrophages. moreover, anti-tnf-alpha antibodies inhibit lps-stimulated phosphorylation of eif-4e and p220 b ... | 1992 | 1345341 |
| a key role for type 1 pili in enterobacterial communicability. | up to 80% of faecal escherichia coli strains are able to produce type 1 pili. these filamentous bacterial surface organelles, which mediate mannose-sensitive attachment to mammalian epithelial cells, are also conserved throughout the enterobacteriaceae. as a potential explanation for their prevalence among intestinal isolates of enteric bacteria, it has been widely speculated that type 1 pili are important for adherence to the host's intestinal mucosa. however, conclusive evidence for this idea ... | 1992 | 1349417 |
| adaptive regulation in skeletal muscle glutamine metabolism in endotoxin-treated rats. | the effects of a single dose of endotoxin (7.5 mg/kg bw) on skeletal muscle glutamine metabolism were studied in vivo in rats to gain further understanding of the altered glutamine metabolism that characterizes sepsis and other catabolic diseases. in endotoxin-treated animals the arterial glutamine concentration fell early initially and then increased compared with control values. twelve hours after treatment, the arteriovenous concentration difference for glutamine across the hindquarter double ... | 1992 | 1350313 |
| purification and characterization of the blue-green rat phaeochromocytoma (pc12) tyrosine hydroxylase with a dopamine-fe(iii) complex. reversal of the endogenous feedback inhibition by phosphorylation of serine-40. | tyrosine hydroxylase (th) was purified from tumours of rat phaeochromocytoma (pc12) cells by a three-step purification procedure giving 30 mg of pure enzyme in 3 days. the enzyme sedimented with an s(eo),w value of 9.2 s and revealed an apparent subunit molecular mass of 62 kda with a minor 60 kda component. two-dimensional gel isoelectric focusing/electrophoresis and tryptic digestion revealed that the heterogeneity could be accounted for by limited proteolysis of the 62 kda component and the p ... | 1992 | 1352446 |
| peroxisomal acetoacetyl-coa thiolase of an n-alkane-utilizing yeast, candida tropicalis. | two genes encoding acetoacetyl-coa thiolase (thiolase i; ec 2.3.1.9), whose localization in peroxisomes was first found with an n-alkane-utilizing yeast, candida tropicalis, were isolated from the lambda embl3 genomic dna library prepared from the yeast genomic dna. nucleotide sequence analysis revealed that both genes contained open reading frames of 1209 bp corresponding to 403 amino acid residues with methionine at the n-terminus, which were named as thiolase ia and thiolase ib. the calculate ... | 1992 | 1362382 |
| the gene encoding the biotin carboxylase subunit of escherichia coli acetyl-coa carboxylase. | we report the molecular cloning and dna sequence of the gene encoding the biotin carboxylase subunit of escherichia coli acetyl-coa carboxylase. the biotin carboxylase gene encodes a protein of 449 residues that is strikingly similar to amino-terminal segments of two biotin-dependent carboxylase proteins, yeast pyruvate carboxylase and the alpha-subunit of rat propionyl-coa carboxylase. the deduced biotin carboxylase sequence contains a consensus atp binding site and a cysteine-containing sequen ... | 1992 | 1370469 |
| purification and characterization of soluble forms of human and rat stem cell factor recombinantly expressed by escherichia coli and by chinese hamster ovary cells. | stem cell factor (scf) is a novel, early-acting hematopoietic factor. it was isolated from the medium of a rat cell line in a soluble, processed form (zsebo et al., 1990, cell 63, 195). the cloned human and rat genes encode the soluble form plus additional c-terminal amino acids including a hydrophobic transmembrane domain (martin et al., 1990, cell 63, 203). we have recombinantly expressed forms of human and rat scf corresponding to the soluble, processed form in escherichia coli and in chinese ... | 1992 | 1374224 |
| induction by fungal elicitor of s-adenosyl-l-methionine synthetase and s-adenosyl-l-homocysteine hydrolase mrnas in cultured cells and leaves of petroselinum crispum. | treatment of cultured parsley (petroselinum crispum) cells with fungal elicitor rapidly activates transcription of many genes encoding specific steps in pathogen defense-related pathways. we report evidence that three cdnas corresponding to such genes represent two key enzymes of the activated methyl cycle. two cdnas are derived from distinct members of the s-adenosyl-l-methionine synthetase gene family, based on extensive similarity of the deduced polypeptides with authentic enzymes from arabid ... | 1992 | 1374911 |
| molecular and immunological characterization of adp-ribosylarginine hydrolases. | mono-adp-ribosylation is a reversible modification of proteins with nad:arginine adp-ribosyltransferases and adp-ribosylarginine hydrolases catalyzing the forward and reverse reactions, respectively. hydrolase activities were present in a variety of animal species, with the highest specific activities found in rat and mouse brain, spleen, and testis. rat and mouse hydrolases were dithiothreitol- and mg(2+)-dependent, whereas the bovine and guinea pig enzymes were dithiothreitol-independent. a ra ... | 1992 | 1375222 |
| monoclonal antibodies against bacterial glucosamine 6-phosphate synthase: production and use for structural studies. | fifteen mouse x rat hybridoma cell lines producing rat monoclonal antibodies (mabs) directed to escherichia coli glucosamine 6-p synthase (glms) were established and characterized. most of them (13/15) are igg2a while 2 were typed as igg1. their kaff ranged from 1.5 x 10(6) to 9.6 x 10(8) m-1 as determined by beatty et al. (1). the epitopes recognized by these mabs were assigned to one of the two catalytical domains of the enzyme (ct1 and ct2) as demonstrated both by elisa and western-blotting u ... | 1992 | 1376719 |
| sepsis-induced changes in protein synthesis: differential effects on fast- and slow-twitch muscles. | sepsis is associated with severe muscle wasting. mechanisms responsible for sepsis-induced alterations in muscle protein metabolism were investigated in vivo and compared with changes induced by nonseptic inflammation. the rate of protein synthesis in mixed hindlimb muscles was not altered in inflammation but was inhibited 50% in sepsis. this inhibition did not result from a decreased rna content. instead, the translational efficiency was significantly reduced by 50% in skeletal muscle of septic ... | 1992 | 1377447 |
| molecular cloning, stage-specific expression and cellular distribution of a putative protein kinase from plasmodium falciparum. | a putative protein kinase gene (pfpk2) has been isolated from the human parasite plasmodium falciparum by using a mixed oligonucleotide pool which corresponds to a highly conserved region of serine/threonine protein kinases. the complete nucleotide sequence of 5 kb suggests the existence of a second transcriptional unit besides that of the pfpk2 gene, separated by a highly (a+t)-rich region and transcribed in a different orientation. no intron sequence exists in pfpk2. the predicted amino acid s ... | 1992 | 1378403 |
| interaction of charybdotoxin with permeant ions inside the pore of a k+ channel. | charybdotoxin (ctx) blocks high conductance ca(2+)-activated k+ channels by binding to a receptor site in the externally facing "mouth." toxin bound to the channel can be destabilized from its site by k+ entering the channel from the opposite, internal, solution. by analyzing point mutants of ctx expressed in e. coli, assayed with single ca(2+)-activated k+ channels reconstituted into planar lipid bilayers, we show that a single positively charged residue of the peptide, lys-27, wholly mediates ... | 1992 | 1379820 |
| cloning and expression of the gal beta 1, 3galnac alpha 2,3-sialyltransferase. | sequence information obtained by nh2-terminal sequence analysis of two molecular weight forms (45 and 48 kda) of the porcine gal beta 1,3galnac alpha 2,3-sialyltransferase was used to clone a full-length cdna of the enzyme. the cdna sequence revealed an open reading frame coding for 343 amino acids and a putative domain structure consisting of a short nh2-terminal cytoplasmic domain, a signal-anchor sequence, and a large cooh-terminal catalytic domain. this domain structure was confirmed by cons ... | 1992 | 1383214 |
| interaction of singlet oxygen with dna and biological consequences. | to study the interaction of singlet oxygen (1o2) with dna and the biological consequences of 1o2-induced dna damage, we used the thermodissociable endoperoxide of 3,3'-(1,4 naphthalidene) dipropionate (ndpo2) as a generator of free 1o2 in reactions with (1) 2'-deoxynucleoside 3'-monophosphates (dnps), (2) an oligonucleotide (16-mer) having one deoxyguanine (dg), (3) native and denaturated rat kidney dna and (4) single-stranded (ss) and double-stranded (ds) bacteriophage m13mp10 dna. using both a ... | 1992 | 1383778 |
| endothelium-accelerated hyporesponsiveness of norepinephrine-elicited contraction of rat aorta in the presence of bacterial lipopolysaccharide. | the role of the endothelium in the hyporesponsiveness of alpha-adrenoceptor-mediated contractions of the rat aorta was investigated. the norepinephrine-induced maximal contraction was diminished after repeated addition of the agonist. the hyporesponsiveness of the maximal contraction was endothelium dependent, being prevented by ng-monomethyl-l-arginine (0.5 mm), l-argininosuccinic acid (0.5 mm), puromycin (ic50 = 100 microm), actinomycin d (ic50 = 80 nm) but not by indomethacin, which suggests ... | 1992 | 1385173 |
| 4-(1,2-benzisothiazol-3-yl)alkanoic and phenylalkanoic acids: synthesis and anti-inflammatory, analgesic and antipyretic activities. | continuing their studies on benzisothiazolyl derivatives, authors refer to the preparation and pharmacological properties of 4-(1,2-benzisothiazol-3-yl) alkanoic and phenylalkanoic acids. all substances were tested for anti-inflammatory, analgesic and antipyretic properties. as reference compounds, 1,2-benzisothiazolin-3-one and 4-(3-oxo-1,2-benzisothiazolin-3-yl) phenylacetic acid, as prototypes of benzisothiazolinonic derivation. ibuprofen, as a prototype of substituted arylalkanoic acids, and ... | 1992 | 1388601 |
| marked enhancement of rat urinary bladder carcinogenesis by heat-killed escherichia coli. | chronic urinary tract infection is an important risk factor for the development of carcinoma in the human urinary bladder. to test the effect of chronic persistent inflammation on bladder carcinogenesis, we instilled heat-killed escherichia coli (1 x 10(8) cells suspended in 0.5 ml of phosphate-buffered 2.1% nacl solution) twice a week into the heterotopically transplanted rat urinary bladders in which carcinogenesis was initiated by a single dose (0.25 mg) of n-methyl-n-nitrosourea. when compar ... | 1992 | 1394138 |
| identification of tumor necrosis factor as a transcriptional regulator of the phosphoenolpyruvate carboxykinase gene following endotoxin treatment of mice. | the decreased synthesis of hepatic phosphoenolpyruvate carboxykinase (pepck), the rate-limiting enzyme of gluconeogenesis, that occurs during endotoxemia was shown previously in rats to occur at the transcriptional level. in the current study, the exogenous administration of human recombinant tumor necrosis factor (tnf), a proximal mediator of endotoxic shock, reduced the pepck transcription rate, mrnapepck levels, and pepck enzyme activity in a time- and dose-dependent manner in cd-1 mice. comp ... | 1992 | 1398916 |
| tissue-specific regulation of renin-binding protein gene expression in rats. | rat gene for renin-binding protein (rnbp) was shown to be expressed in the kidney, adrenal gland, brain, lung, spleen, ovary, testis, and heart. on sodium depletion and captopril administration, the rat showed a marked increase in the adrenal rnbp mrna level and a slight decrease in the kidney rnbp mrna level. in two-kidney, one clip hypertensive rats, the rnbp mrna levels of the clipped and contralateral kidneys were unchanged and also its adrenal mrna level was maintained at the control level. ... | 1992 | 1400260 |
| precursor structure, expression, and tissue distribution of human guanylin. | heat-stable enterotoxins (sta) are small, cysteine-rich peptides secreted by escherichia coli that are able to induce diarrhea through the stimulation of an intestine-specific receptor-guanylyl cyclase known as star. a 15-amino acid peptide, guanylin, was recently purified from rat jejunum and proposed to be a potential endogenous activator of this receptor. we describe here the cloning and characterization of human and mouse cdnas encoding precursor proteins of 115 and 116 amino acids, respecti ... | 1992 | 1409606 |
| reveromycins, new inhibitors of eukaryotic cell growth. ii. biological activities. | reveromycins a, b, c and d showed inhibitory activity against egf-stimulated mitogen response in balb/mk cells. furthermore reveromycins a, c and d exhibited morphological reversion of srcts-nrk cells, antiproliferative activity against human tumor cell lines and antifungal activity. the effects of reveromycins a, c and d on eukaryotic cells were closely similar to each other, but those of reveromycin b were very weak. in vitro studies revealed that reveromycin a is a selective inhibitor of prot ... | 1992 | 1429226 |
| studies of the catalytic activities and substrate specificities of saccharomyces cerevisiae myristoyl-coenzyme a: protein n-myristoyltransferase deletion mutants and human/yeast nmt chimeras in escherichia coli and s. cerevisiae. | saccharomyces cerevisiae myristoyl-coa:protein n-myristoyltransferase (nmt1p) is an essential, 455-residue, monomeric enzyme. amino- and carboxyl-terminal deletion mutants of nmt1p were genetically engineered to determine the minimal domain necessary to maintain catalytic activity. enzyme activity was assessed by (i) sequentially inducing nmt1p or its mutant derivatives and one of two eukaryotic substrates for the wild type enzyme (s. cerevisiae gpa1p and rat go alpha) in escherichia coli, a bac ... | 1992 | 1429724 |
| the human tpr gene encodes a protein of 2094 amino acids that has extensive coiled-coil regions and an acidic c-terminal domain. | we recently provided evidence that the human tpr gene encodes a 726 amino acid protein (designated tpr-s) and identified an alternatively spliced transcript that encodes a larger tpr protein with an extended c-terminal domain. in this study, through isolation and sequencing of tpr cdna clones, we have established that this alternatively spliced transcript encodes a protein of 2094 amino acids (designated tpr-l). the larger tpr protein is predicted to have extensive regions of alpha-helix and sev ... | 1992 | 1437155 |
| rfp is a dna binding protein associated with the nuclear matrix. | we reported that the rfp gene encodes a protein with putative zinc finger domains and was involved in the activation of the ret proto-oncogene. to further characterize the rfp protein, we developed a polyclonal antibody against the product synthesized from a fragment of the rfp cdna expressed in escherichia coli. western blot analysis showed that rfp was identified as a 58 kda protein in cell lysates from four human and rodent cell lines and from mouse testis. in addition, a unique 68 kda protei ... | 1992 | 1437549 |
| high-level expression in escherichia coli of enzymatically active fusion proteins containing the domains of mammalian cytochromes p450 and nadph-p450 reductase flavoprotein. | this report describes the properties of two mammalian cytochromes p450 that have been expressed at high levels in escherichia coli as enzymatically active fusion proteins containing the flavoprotein domain of rat nadph-cytochrome p450 reductase (ec 1.6.2.4). fusion proteins were prepared by engineering the cdnas for the steroid-metabolizing bovine adrenal p450 17a with the cdna for rat liver nadph-p450 reductase with the introduction of a ser-thr linker to give a protein we have named rf450[mbov ... | 1992 | 1438282 |
| modes of action and inhibitory activities of new siderophore-beta-lactam conjugates that use specific iron uptake pathways for entry into bacteria. | we describe here the mechanism of inhibition of two new siderophore-beta-lactam conjugates against escherichia coli x580. one conjugate is a spermidine-based catechol siderophore-carbacephalosporin (jam-2-263), and the other is an n5-acetyl-n5-hydroxy-l-ornithine tripeptide hydroxamate siderophore-carbacephalosporin (ekd-3-88). in an agar diffusion test, both conjugates produced large inhibitory zones against strain x580. resistant strains (i.e., jamr and ekdr) could be isolated after exposure o ... | 1992 | 1444296 |
| pharmacokinetics of 18f-labeled fleroxacin in rabbits with escherichia coli infections, studied with positron emission tomography. | 18f-labeled fleroxacin was used to measure the pharmacokinetics of fleroxacin in healthy and infected animals by positron emission tomography (pet) and tissue radioactivity measurements. in all experiments, a pharmacological dose of unlabeled drug (10 mg/kg) was coinjected with the tracer. the pharmacokinetics of [18f]fleroxacin was measured in groups of healthy mice (n = six per group) at 10, 30, 60, and 120 min after injection and in groups of rats with escherichia coli thigh infections (n = s ... | 1992 | 1444310 |
| heat stress of cultured gc cells enhances triiodothyronine-induced growth hormone production by action within the 5'-flanking region of the rat growth hormone gene. | we studied the effect of incubation at 41 c on a clone of gc cells that had previously been stably transfected with a gene construct, pghxgpt, containing -1800 to +8 of the rat growth hormone promoter fused to the structural gene for e. coli xanthine guanine phosphoribosyl-transferase. the effect of incubation of the clone containing pghxgpt at 41 c was to enhance triiodothyronine induction of growth hormone secretion (2-fold, p < 0.01) and of xanthine quanine phosphoribosyl-transferase activity ... | 1992 | 1445309 |
| nuclear localization and hepatic zonation of rat "spot 14" protein: immunohistochemical investigation employing anti-fusion protein antibodies. | s14 protein and mrna levels are rapidly regulated by hormones and diet. we have purified a 45-kd fusion protein from lysates of transformed e. coli that includes the entire s14 polypeptide. affinity-purified rabbit anti-fusion protein antibodies were used in immunohistochemistry to determine the distribution of s14 protein across the hepatic lobule, and to reassess its intracellular location. in hyperthyroid liver, s14 protein clustered near the central venous zone, and was not detectable in the ... | 1992 | 1446647 |
| acute heat stress protects rats against endotoxin shock. | the purpose of this study was to determine 1) whether prior (24-h) heat stress could render rats cross-resistant to the lethal activity of bacterial lipopolysaccharide (lps) and 2) whether this acquired state of resistance is associated with endotoxemia during the heat stress event. four groups (n = 7/group) of rats were examined: 1) saline treated, 2) lps treated, 3) heat stressed and saline treated, and 4) heat stressed and lps treated. saline or lps (escherichia coli, serotype 0111:b4, 20 mg/ ... | 1992 | 1447099 |
| ovine pulmonary surfactant induces killing of pasteurella haemolytica, escherichia coli, and klebsiella pneumoniae by normal serum. | pulmonary surfactant has been shown to play an increasingly important role in bacterial clearance at the alveolar surface in the lung. this study describes a bactericidal mechanism in which ovine pulmonary surfactant induces killing of pasteurella haemolytica by normal serum. to demonstrate killing, six bacterial species were incubated first with pulmonary surfactant for 60 min at 37 degrees c and then with serum for an additional 60 min at 37 degrees c. p. haemolytica type a1 strains 82-25 and ... | 1992 | 1452351 |
| development of an irradiated vaccine that protects against enterotoxigenic escherichia coli diarrhoea. | in the pathogenesis of diarrhoea in man bacteria adhesion to enterocytes is mediated by specific cfa/i or cfa/ii antigens. a perorally administered vaccine was prepared from e. coli h10407 (078:h11) by irradiation with electrons with high energy (ehe). two hours after cimetidine administration rats were immunized per os with 5 irradiated vaccine doses at 4-day intervals. seven days after the last immunization animals were infected by inoculating 1 x 10(9) germs in the ligated intestinal loop. re ... | 1992 | 1457822 |
| site-directed mutation makes rabbit calcyclin dimer. | unlike human, rat and mouse calcyclin, purified rabbit calcyclin did not form a dimer on tricine sds-page under non-reduced conditions. based on the internal peptide sequence of rabbit calcylin, we isolated and sequenced a cdna clone encoding calcyclin. the sequence of this clone (pcalc) is 629 bp long and codes 90 amino acid residues of a protein with a molecular mass of 10,153 da. by northern blot analysis, a major band of 0.9 kbp and a minor band of 2.6 kbp were detected in the lung. the reco ... | 1992 | 1459239 |
| cloning, sequencing, and expression of the fadd gene of escherichia coli encoding acyl coenzyme a synthetase. | in the enteric bacterium, escherichia coli, acyl coenzyme a synthetase (fatty acid:coa ligase (amp-forming) ec 6.2.1.3) activates exogenous long-chain fatty acids concomitant with their transport across the inner membrane into metabolically active coa thioesters. these compounds serve as substrates for acyl-coa dehydrogenase in the first step in the process of beta-oxidation. the acyl-coa synthetase structural gene, fadd, has been identified on clone 6d1 of the kohara e. coli gene library and by ... | 1992 | 1460045 |
| expression of a catalytically active human cytochrome p-4502e1 in escherichia coli. | the cdna coding for human cytochrome p-4502e1 has been expressed in escherichia coli by placing it under the control of the isopropylthiogalactoside inducible trc promoter. production of p4502e1 was demonstrated by immunoblots and by catalytic activity with dimethylnitrosamine as substrate. modifications which favor expression in e. coli were made within the first seven codons. this resulted in approx. a 2- to 2.5-fold increase in p4502e1 isolated from the bacterial membranes as detected by immu ... | 1992 | 1472537 |
| a polyclonal antibody to the rat oestrogen receptor expressed in escherichia coli: characterization and application to immunohistochemistry. | a rat oestrogen receptor-beta-galactosidase fusion protein was expressed using a pex2/rat oestrogen receptor cdna construct. scatchard analysis of [3h]oestradiol-17 beta binding to the cell lysate revealed that the fusion protein had functional binding sites specific for oestradiol with a dissociation constant of 1.49 nmol/l. the relative molecular weight (m(r)) of the fusion protein was determined as 180,000 by immunoblot analysis of the cell lysate employing a monoclonal antibody to the human ... | 1992 | 1474341 |
| pathogenicity of bacteroides fragilis group in rat intra-abdominal abscesses. | attempts were made to study the pathogenicity of some strains of bacteroides fragilis group in the rat intra-abdominal abscess model. multiple intraabdominal abscesses were produced in 50 to 70% of animals when an inoculum containing 10(9) cfu/ml of any of the five species of bacteroides fragilis group was injected. rising homologous antibody titers determined by indirect fluorescent antibody test were observed till the 3rd week when tested last, indirectly confirming the multiplication of the o ... | 1992 | 1479960 |
| in vivo effects of endotoxin on intraepithelial mucosubstances in rat pulmonary airways. quantitative histochemistry. | bacteria-induced bronchopneumonias are often characterized by an influx of neutrophils and excess mucus in pulmonary airways. this study determined how endotoxin, a component of gram-negative bacteria and a potent inflammatory agent, affects the ultrastructure of the mucociliary apparatus and the amount of stored intraepithelial mucosubstances in the main axial airways within the lung. rats were intranasally instilled, once a day for 3 days, with endotoxin or saline (controls). animals were sacr ... | 1992 | 1497089 |
| ubiquitous presence in mammalian cells of enzymatic activity specifically cleaving 8-hydroxyguanine-containing dna. | here we report the finding of enzymatic activity that specifically cleaves dna containing 8-hydroxyguanine (oh8gua) residues in various mammalian cells. to detect this activity, we used a synthetic double-stranded dna containing a single oh8gua at a defined position as the substrate, and analyzed the products of enzymatic digestion by polyacrylamide gel electrophoresis. two cleavage sites near the oh8gua residue were detected with partially purified fractions from cow brain and rat liver, and al ... | 1992 | 1506269 |
| thyroid hormone alters in vitro dna binding of monomers and dimers of thyroid hormone receptors. | t3 binds to intranuclear thyroid hormone receptors (trs) on target dna elements and exerts profound influences on gene expression by mechanisms not yet characterized. we used gel shift assays and cross-linking experiments to demonstrate that t3 greatly induced the monomeric binding of the htr beta produced in escherichia coli to dna. t3 also increased the gel mobility of these monomer-dna complexes suggesting they undergo a ligand-induced conformational change. this effect did not depend on the ... | 1992 | 1508227 |
| on the fibrinolytic system in aged rats, and its reactivity to endotoxin and cytokines. | aged rats are more susceptible to endotoxin-induced effects, including microthrombosis and platelet aggregation, than are young rats. to investigate whether changes in the fibrinolytic system might be involved, we investigated the fibrinolytic activity in plasma euglobulin fractions and tissues (lung and heart) of young (6-months old) and aged (24-months old) rats under baseline conditions and after challenge with endotoxin. aged rats had lower plasma levels of tissue-type plasminogen activator ... | 1992 | 1509412 |
| endotoxin-induced fever is modulated by endogenous glucocorticoids in rats. | this study was designed to determine if the febrile response, similar to the inflammatory response, can be modulated by endogenous glucocorticoids. a single intraperitoneal injection of lipopolysaccharide (lps, 200 micrograms/kg) induced a significant increase in rectal temperature of unrestrained rats maintained within the thermoneutral zone. the febrile response was fully abolished following treatment with a glucocorticoid, dexamethasone (dex), but was not affected by a mineralocorticoid, deox ... | 1992 | 1510181 |
| reactive oxygen-reducing and protein-refolding activities of adult t cell leukemia-derived factor/human thioredoxin. | reducing and protein-refolding activities of adult t cell leukemia-derived factor (adf)/human thioredoxin were studied. recombinant adf/human thioredoxin produced by e. coli, which has an insulin-reducing activity as efficient as that of e. coli thioredoxin, also reduced some reactive oxygen species, such as hydrogen peroxide. furthermore, recombinant adf/human thioredoxin was found to have protein-refolding activity for scrambled (mispaired disulfide-containing) rnase a. cys-31 at the active si ... | 1992 | 1510657 |
| production and characterization of recombinant chicken insulin-like growth factor-i from escherichia coli. | recombinant chicken insulin-like growth factor-i (cigf-i) has been produced in escherichia coli after first modifying a plasmid that coded for a human igf-i (higf-i) fusion protein, in order to introduce codons for the eight amino acid substitutions. the cigf-i fusion protein, deposited in bacterial inclusion bodies, was dissolved under reducing conditions, desalted, subjected to anion-exchange chromatography to remove proteinases, refolded and partially purified by reverse-phase high-performanc ... | 1992 | 1515028 |
| effects of n-acetylcysteine on diaphragmatic function and malondialdehyde content in escherichia coli endotoxemic rats. | we evaluated the effects of sublethal escherichia coli endotoxemia with or without concomitant administration of n-acetylcysteine, an antioxidant agent, on diaphragmatic strength, endurance, and malondialdehyde (mda) content in rats. one hundred ninety rats were inoculated subcutaneously on 2 successive days with 0.6 and 1.2 mg/100 g body weight of e. coli lipopolysaccharide respectively (e animals, n = 100) or saline (c group, n = 90). e and c animals were divided into two groups based on admin ... | 1992 | 1519854 |
| association of the 90-kda heat shock protein does not affect the ligand-binding ability of androgen receptor. | an n-terminal truncated androgen receptor with putative dna- and ligand-binding domains (ar438) and that with a ligand-binding domain (ar612) were expressed under control of the t7 promoter in e. coli or translated in vitro with rabbit reticulocyte lysate, and their ligand-binding properties and the interaction with hsp90 were investigated. bacterially expressed ar438 and ar612 bound a synthetic androgen, [3h]r1881, with apparent dissociation constants of 2.6 +/- 0.2 and 3.1 +/- 0.7 nm, respecti ... | 1992 | 1525041 |
| [the use of plasma from donor convalescent patients in the combined treatment of peritonitis]. | the article analyses the treatment of 12 patients with diffuse purulent peritonitis in whom the titers of specific antibodies against microflora causing peritonitis were corrected in the period of secondary immunodeficiency. the authors suggest a new method for the treatment of peritonitis which is based on inclusion of convalescents' plasma after peritonitis in the therapeutic complex. this plasma contains specific antibodies against the cultured microflora in high titers and is a polyvalent hy ... | 1992 | 1527978 |
| antimicrobial gentamicin activity in the presence of exogenous protease inhibitor (bowman-birk inhibitor) in gentamicin-induced nephrotoxicity in rats. | in our previous studies, we found increased levels of urinary trypsin inhibitory activity in gentamicin-induced nephrotoxicity in rats. following administration of the bowman-birk trypsin and chymotrypsin inhibitor (bbi), no proteinuria was detected in gentamicin-treated rats, and a decrease in creatinine clearance was noted in only 50% of the injected rats. in the present study, we examined the antimicrobial activity of gentamicin against escherichia coli in the presence of bbi in gentamicin-in ... | 1992 | 1528344 |
| high-level expression of functional human cytochrome p450 1a2 in escherichia coli. | enzymatically active human cytochrome p450 1a2 was expressed in escherichia coli utilizing the pcwori+ vector containing a modified cdna. the coding sequence for the nh2-terminal region of the protein was modified by the alignment and substitution of a 27 bp segment from a modified bovine p450 17a1 cdna onto the 5' end of the open reading frame of p450 1a2 at amino acid 21. the expressed chimeric p450 was produced at a high level in a functionally intact form, as assayed by the formation in vivo ... | 1992 | 1537466 |
| response elements of the androgen-regulated c3 gene. | intron and 5'-flanking regions of the androgen-regulated c3 subunit gene contain potential cis-acting transcription control sequences including several 15-base pair (bp) partial palindromes resembling response elements for glucocorticoid (gre) and progesterone (pre) receptors. specific dna binding of the androgen receptor (ar) and androgen-dependent activation of transcription indicate that some of these gre/pre-like sequences are capable of functioning as androgen response elements (are). a 0.3 ... | 1992 | 1537831 |
| neutrophil depletion protects against liver injury from bacterial endotoxin. | neutrophil (pmn) infiltration is an early occurrence in the liver after exposure to hepatotoxic doses of endotoxin lipopolysaccharide (lps). the purpose of this study was to test the hypothesis that pmns contribute to the pathogenesis of lps hepatotoxicity. the immunoglobulin fraction from serum of rabbits immunized with rat pmns (anti-pmn ig) was administered intravenously to rats 18 and 6 hours before exposure to an hepatotoxic dose of lps (escherichia coli 0128:b12). this protocol caused a gr ... | 1992 | 1538588 |
| different conformational forms of escherichia coli and rat liver 5s rrna revealed by pb(ii)-induced hydrolysis. | different stable forms of escherichia coli and rat liver 5s rrna have been probed by pb(ii)-induced hydrolysis. in the native a forms of 5s rrna, pb2+ reveal single-stranded rna stretches and regions of increased conformational flexibility or distorted by the presence of bulged nucleotides. hydrolysis of urea/edta-treated e. coli 5s rrna (b form) shows the presence of two strong helical domains; helix a retained from the a form and a helix composed of rna regions g33-c42 and g79-c88. other rna r ... | 1992 | 1541274 |
| expression of porcine complement cytolysis inhibitor mrna in cultured aortic smooth muscle cells. changes during differentiation in vitro. | porcine smooth muscle cells (smc) grown to a high density monolayer culture undergo a morphological transition in which the cells draw away from the substrate and form multicellular nodules. the cells within the nodule resemble smc in the aortic media and in some atherosclerotic plaques. the process of nodule formation is associated with the enhanced production of a secreted 38-kda glycoprotein. to characterize the 38-kda protein and its expression, a cdna clone (pc38k) was isolated by immunolog ... | 1992 | 1544909 |
| site-directed mutagenesis of rat liver nad(p)h: quinone oxidoreductase: roles of lysine 76 and cysteine 179. | we previously reported the expression of a full-length cdna complementary to a rat liver nad(p)h:quinone oxidoreductase (ec 1.6.99.2) mrna in escherichia coli (q. ma, r. wang, c. s. yang, and a. y. h. lu, 1990, arch. biochem. biophys. 283, 311-317). since cysteine residues have been suggested to be important for the catalysis of flavoproteins and a lysine residue at position 76 in nad(p)h:quinone oxidoreductase has been proposed to be involved in electron transfer of the enzyme, we investigated ... | 1992 | 1567199 |
| 31p nmr spectroscopic studies on purified, native and cloned, expressed forms of nadph-cytochrome p450 reductase. | 31p nmr spectroscopy has been utilized in conjunction with site-directed mutagenesis and phospholipid analysis to determine structural aspects of the prosthetic flavins, fad and fmn, of nadph-cytochrome p450 reductase. comparisons are made among detergent-solubilized and protease (steapsin)-solubilized preparations of porcine liver reductases, showing unequivocally that the 31p nmr signals at approximately 0.0 ppm in the detergent-solubilized, hydrophobic form are attributable to phospholipids. ... | 1992 | 1567869 |
| the association between meningitis and dural puncture in bacteremic rats. | clinicians have long been concerned that performance of spinal anesthesia during a period of bacteremia may result in the subsequent development of meningitis. in order to determine whether such an association exists, percutaneous dural puncture was performed in 40 animals during a period of escherichia coli bacteremia. twenty-four hours later, spinal fluid was obtained for final analysis by surgically draining the cisterna magna. twelve animals had e. coli recovered from the surgically drained ... | 1992 | 1575342 |
| immune response of cattle to haemophilus somnus lipid a-protein conjugate vaccine and efficacy in a mouse abortion model. | immunogenicity of the lipid a component of haemophilus somnus lipooligosaccharide in cattle and mice was examined after purification, detoxification, and covalent conjugation to a protein carrier. after 2 inoculations, a substantial antibody response was induced in most cattle to lipid a and the protein carrier. to determine whether antibodies to lipid a would be protective, 5 x 10(7) colony-forming units of h somnus strain 649 were administered iv to endotoxin-responsive (c3h/hen) mice. in one ... | 1992 | 1575380 |
| human heme oxygenase-2: characterization and expression of a full-length cdna and evidence suggesting that the two ho-2 transcripts may differ by choice of polyadenylation signal. | we show by northern blot analysis that human ho-2 is encoded by two transcripts (1.3 and 1.7 kb) and is a single-copy gene as judged by southern blot analysis. we further provide evidence based on northern blot and sequence analysis of a cdna representing the larger transcript that the transcripts differ in the 3' untranslated region. a 274-base-pair dna fragment from the rat heme oxygenase-2 gene (i. cruse and m.d. maines, 1988, j. biol. chem. 263, 3348-3353) was used to isolate a human ho-2 cd ... | 1992 | 1575508 |
| effects of nicardipine in rats subjected to endotoxic shock. | 1. the calcium channel blocker, nicardipine, produced a dose-dependent reduction in the mortality caused by endotoxin in rats. 2. the drug also reduced most of the hematological and gross pathological manifestations of disseminated intravascular coagulation (dic) caused by endotoxin. 3. the endotoxin-induced monocytopenia but not the granulocytopenia, lymphocytopenia or thrombocytopenia was inhibited by the drug. 4. the results suggest that the protective action of nicardipine is causally relate ... | 1992 | 1592229 |
| rat cystathionine beta-synthase. gene organization and alternative splicing. | we elucidated the structure and alternative splicing patterns of the rat cystathionine beta-synthase gene. the gene is 20-25 kilobase pairs long, and its coding region is divided into 17 exons. these are alternatively spliced, forming four distinct mrnas (types i through iv). the predicted open reading frames encode proteins of 61.5, 39, 60, and 52.5 kda, respectively. exons 13 and 16 are used alternatively and mutually exclusively. exon 13 includes a stop codon and encodes the unique carboxyl-t ... | 1992 | 1597473 |
| cloning and heterologous expression of cdna encoding class alpha rat glutathione transferase 8-8, an enzyme with high catalytic activity towards genotoxic alpha,beta-unsaturated carbonyl compounds. | a cdna clone, lambda gtra8, encoding rat glutathione transferase subunit 8 has been isolated from a lambda gt10 rat hepatoma cdna library. the previously known amino acid sequence of the enzyme was used to design primers for a polymerase chain reaction that yielded a 0.3 kb dna fragment from the hepatoma library. the 0.3 kb fragment was used as a probe for screening and a 0.9 kb cdna clone containing a complete open reading frame was obtained. after dna sequencing and subcloning into an expressi ... | 1992 | 1599415 |
| insulin receptor and epidermal growth factor receptor dephosphorylation by three major rat liver protein-tyrosine phosphatases expressed in a recombinant bacterial system. | protein-tyrosine phosphatases (ptpases) play an essential role in the regulation of signal transduction mediated by reversible protein-tyrosine phosphorylation. in order to characterize individual rat hepatic ptpases that might have specificity for autophosphorylated receptor tyrosine kinases, we isolated cdna segments encoding three ptpases (ptpase 1b, lar and lrp) that are expressed in insulin-sensitive liver and skeletal muscle tissue, and evaluated their catalytic activity in vitro. the intr ... | 1992 | 1599438 |
| expression and purification of biologically active human osf-1 in escherichia coli. | osf-1 (also known as pleiotrophin, hb-gam, hbgf-8 or hbnf) is a heparin-binding, neurotrophic protein. its tissue-specific expression in rats is developmentally regulated and the protein is highly conserved between species. the protein is believed to be involved in neuronal development. previous experiments in our laboratory showed that osf-1 is primarily expressed in brain and bone. the biological function of osf-1 in bone is unknown. in order to overcome the limited availability of the native ... | 1992 | 1599459 |
| rapid translocation of bacteria in small bowel transplantation. | | 1992 | 1604536 |
| the pathobiology of subclinical pyelonephritis--an experimental evaluation. | clinical studies have demonstrated a poor correlation between localization tests, which are designed to determine the site of urinary tract infection, and symptoms of upper urinary tract infection. one explanation is that microorganisms may be present in the kidney but not initiate an inflammatory response with associated symptoms. an animal model has been developed to obtain quantitative information on the comparative pathobiology of lesion-inducing and non-lesion-inducing infections. in this m ... | 1992 | 1614050 |
| high-performance liquid chromatographic method to resolve and determine lipopolysaccharide sub-groups of escherichia coli endotoxin in isolated perfused rat liver perfusate. | a high-performance liquid chromatographic method was developed for resolving heterogeneous preparations of fluorescently labelled endotoxin derived from escherichia coli (serotype 0111:b4) into separate lipopolysaccharide sub-groups. the endotoxin was chromatographed on an analytical gel permeation column using a mobile phase of acetonitrile (20%, v/v) and 100 mm phosphate buffer (ph 7.75). four fluorescent peaks were resolved, representing sub-groups of markedly different molecular sizes. three ... | 1992 | 1618951 |
| rna polymerase ii initiation factor alpha from rat liver is almost identical to human tfiib. | | 1992 | 1620622 |
| endotoxin levels in cirrhotic rats with sterile and infected ascites. | endotoxin levels were measured in sterile and bacterially infected ascites in a rat model of phenobarbital and carbon tetrachloride induced cirrhosis was used. an improved chromogenic substrate assay was used to measure endotoxin. all rat ascites specimens were positive for endotoxin. in culture-negative ascites (n = 8), it ranged from 0.05 eu/ml to 0.14 eu/ml (0.08 +/- 0.04 eu/ml, mean +/- sd) (escherichia coli 0111:b4 endotoxin was used as a reference). in culture-positive ascites (premortem n ... | 1992 | 1624078 |
| inhibition of dna polymerases by tripeptide derivative protease inhibitors. | benzyloxycarbonyl(z)-leu-leu-leu-al and dansyl(dns)-leu-leu-leu-ch2cl, well known as protease inhibitors, effectively inhibit the activities of dna polymerases alpha, beta and gamma from rat liver and pol i from escherichia coli, but the ability of these inhibitors to inhibit terminal deoxynucleotidyl transferase (tdt) is weak. the mode of inhibition by these tripeptide analogues is non-competitive with dntp. the ki values for z-leu-leu-leu-al and dns-leu-leu-leu-ch2cl are 6.25 x 10(-5) m and 6. ... | 1992 | 1627135 |
| rat tumor necrosis factor-alpha. transcription in rat kupffer cells and in vitro posttranslational processing based on a pcr-derived cdna. | a dna fragment with a reading frame of 708 basepairs coding for tnf-alpha from rat liver was cloned by the polymerase chain reaction. using this species-specific cdna a biotin-labelled antisense (-)rna was transcribed. this probe was used for northern blot analysis of tnf-alpha gene activation. exposure of rat kupffer cells to lps led to a time-dependent change of tnf-alpha-mrna expression with a maximum between one and two hours after stimulation. in vitro translation was carried out with sense ... | 1992 | 1627266 |
| serine and threonine catabolism in saccharomyces cerevisiae: the cha1 polypeptide is homologous with other serine and threonine dehydratases. | the catabolic l-serine (l-threonine) dehydratase of saccharomyces cerevisiae allows the yeast to grow on media with l-serine or l-threonine as sole nitrogen source. previously we have cloned the cha1 gene by complementation of a mutant, cha1, lacking the dehydratase activity. here we present the dna sequence of a 1,766-bp fragment of the cha1 region encompassing an open reading frame of 1080 bp. comparison of the predicted amino acid sequence of the cha1 polypeptide with that of other serine/thr ... | 1992 | 1628804 |
| cloning and expression of drosophila hp1 homologs from a mealybug, planococcus citri. | the mealybug chromosome cycle is one of the most dramatic examples of genomic imprinting known. in embryos that are to become male the entire paternal chromosome set becomes heterochromatic and inactive at the blastoderm stage, while the maternal set remains active and euchromatic. hp1 is a protein from drosophila melanogaster, which binds preferentially to heterochromatin on polytene chromosomes and is likely to be a modifier of position effect variegation. this paper describes the isolation an ... | 1992 | 1629256 |
| generation and migration of cells in the developing striatum. | the development of the rat striatum was investigated using a combination of two histochemically distinguishable retrovirus vectors. using this method, it was possible to identify clonal boundaries within the embryonic striatum and thus determine patterns of proliferation, migration, and some lineal relationships. several novel aspects of striatal histogenesis were discovered. striatal progenitor cells do not exhibit a stem cell pattern of division between embryonic day 15 (e15) and e19; a progen ... | 1992 | 1632968 |
| the effect of endotoxemia on concanavalin a induced alterations in cytoplasmic free calcium in rat spleen cells as determined with fluo-3. | the effects of acute (3 h) and chronic (30 h) in vivo infusions of escherichia coli endotoxin on the ca2+ homeostasis of rat spleen cells was investigated. conditions were established for obtaining reliable estimates of [ca2+]i in these cells using the newly-developed ca2+ indicator fluo-3. the resting [ca2+]i of splenocytes and t lymphocyte-enriched preparations were 119 +/- 35 and 102 +/- 31 nm, respectively. treatment of the cells with concanavalin a (con a) resulted in a rapid increase in [c ... | 1992 | 1633610 |
| study on the mutagenicity of brandy with the ara test. | the forward mutation assay to l-arabinose resistance (ara test) in salmonella typhimurium was used to demonstrate that evaporated residues of brandy had direct-acting mutagenic activity. the mutagenicity covered a 100-fold range, from 13482 to 127 arar induced mutants/ml brandy equivalent. rat liver s9 mix suppressed the mutagenic activity of brandy in the ara test. the inactivating capacity was independent of microsomal monoxygenase enzymes and appeared to be mediated through a heat stable comp ... | 1992 | 1635459 |
| identification of enap-1, an antimicrobial peptide from equine neutrophils. | endogenous, cysteine-rich antimicrobial peptides known as defensins are prominent components of human, rabbit, and rat neutrophils, yet little is known about their occurrence in other mammalian species. although we did not detect mature (i.e., processed) defensins in equine neutrophil granules, we found that these granules contained small amounts of other cysteine-rich peptides with antimicrobial activity. one of these, enap-1, was purified by a combination of gel permeation and reversed-phase h ... | 1992 | 1639474 |
| histamine n-methyltransferase from rat kidney. cloning, nucleotide sequence, and expression in escherichia coli cells. | complementary dna clones encoding rat kidney histamine n-methyltransferase have been isolated using synthetic oligonucleotide probes based on partial amino acid sequences of tryptic peptides of the purified enzyme. the 1.3-kilobase cdna consisted of a 5'-noncoding region of 8 nucleotides, a coding region of 885 nucleotides, and a 3'-noncoding region of 369 nucleotides. the encoded protein of 295 amino acid residues had a calculated molecular weight of 33,940.2. after introduction of a prokaryoti ... | 1992 | 1639806 |