abstract stringlengths 1 18k | country stringlengths 2 20 |
|---|---|
Adenomas with potential for malignancy occur frequently in the upper gastrointestinal tract of patients with familial adenomatous polyposis. However, an assessment of relative risk of upper gastrointestinal cancer in patients with adenomatous polyposis has never been performed. Therefore, the incidence rate of upper ga... | US |
A novel TEM-derived plasmid-encoded beta-lactamase, resistant to inhibition by clavulanic acid, has been identified in a clinical strain of Escherichia coli found in Scotland. The beta-lactamase gene was carried on an 81-kb plasmid that conferred no other resistances. The novel enzyme conferred resistance to the amoxyc... | United Kingdom |
A rapidly inducible and tightly regulated system for the expression of protein in yeast is based on a chimeric promoter constructed of two copies of a vitellogenin-estrogen-response element (ERE) which are inserted upstream from the promoter of the yeast gene encoding iso-1-cytochrome c. The chimeric promoter was inser... | US |
Transposition of mini-transposon Tn5supF to phage lambda can be selected in two ways: (i) by plaque formation on a dnaB amber strain of Escherichia coli, which requires expression of the transposon-borne suppressor tRNA gene (supF) during lytic phage growth, or (ii) by lysogenization of a strain with amber mutations in... | US |
We carried out experiments designed to investigate the effects of sarafotoxin-6B (SFTx) on [Ca2+]i in cerebellar astrocytes using the Ca2+ indicator fura-2. Both endothelin-1 and sarafotoxin-6B increased [Ca2+]i in individual cerebellar astrocytes in cell culture. The shape of the response was variable but usually cons... | US |
Porphyromonas gingivalis is a suspected pathogen in rapidly progressive periodontitis (RPP). We have determined the anti-P. gingivalis serum immunoglobulin G (IgG) isotype response and avidity and the subclass titer distributions for 30 RPP patients and 30 age-, sex-, and race-matched healthy subjects by using enzyme-l... | US |
Heat shock treatment of murine macrophages and the J774 cell line resulted in an enhanced capacity to release superoxide anion (O2-) upon stimulation. There was no concomitant increase in hydrogen peroxide production, and the macrophage microbicidal activity against Mycobacterium tuberculosis, Mycobacterium avium compl... | US |
Diacylglycerol, a physiological activator of protein kinase C, was elevated nearly twofold in unstimulated peripheral blood neutrophils from patients with localized juvenile periodontitis compared with cells from normal individuals. These cells also showed an enhanced and prolonged elevation of diglyceride in response ... | US |
Purified and recombinant forms of growth hormone (GH) as well as of recombinant rat gamma interferon (IFN-gamma) enhance the survival of rats deprived of endogenous pituitary GH secretion by hypophysectomy (HX rats) and infected with virulent Salmonella typhimurium. Macrophages obtained from rats with intact pituitarie... | US |
The microsomal fraction of rabbit liver contains an endopeptidase that cleaves synthetic peptides that mimic the amino acid sequences of the processing sites of many proproteins, including the vitamin K-dependent proteins. The endopeptidase (M(r) 69,000) was extracted from liver microsomes with 1% Lubrol and purified a... | US |
1,2-Dehydro-N-acetyldopamine (dehydro-NADA) is an important catecholamine derivative involved in the cross-linking of insect cuticular components during sclerotization. Since sclerotization is a vital process for the survival of insects, and is closely related to melanogenesis, it is of interest to unravel the chemical... | US |
The DNA sequence of the sulfate activation locus from Escherichia coli K-12 has been determined. The sequence includes the structural genes encoding the enzymes ATP sulfurylase (cysD and cysN) and APS kinase (cysC) which catalyze the synthesis of activated sulfate. These are the only genes known to reside in the sulfat... | US |
We demonstrated previously tyrosine phosphorylation-dependent modulation of phospholipase C-gamma 1 (PLC-gamma 1) catalytic activity (Nishibe, S., Wahl, M. I., Hernandez-Sotomayor, S. M. T., Tonks, N. K., Rhee, S. G., and Carpenter, G. (1990) Science 250, 1253-1256). The increase in PLC-gamma 1 catalytic activity in A-... | US |
Mammalian RNA polymerase II contains at the C terminus of its largest subunit an unusual domain consisting of 52 tandem repeats of the consensus sequence Tyr-Ser-Pro-Thr-Ser-Pro-Ser. The phosphorylation of this domain is thought to play an important role in the transition of RNA polymerase II from a preinitiation compl... | US |
We have assessed the effects of endothelin-1 (ET-1) on transmembrane signaling in adult rat ventricular myocytes. ET-1 stimulates phosphoinositide hydrolysis with an EC50 of 0.3-0.8 nM. This stimulation is linear for up to 30 min in the presence of a protease inhibitor, is additive with the effects of other stimulators... | US |
Several studies indicate that active oxygen species play an important role in the development of pulmonary disease (asbestosis and silicosis) after exposure to mineral dust. The present study was conducted to determine if inhaled fibrogenic minerals induced changes in gene expression and activities of antioxidant enzym... | US |
n-Butyrate, a short chain fatty acid that is produced by colonic bacterial fermentation, is detectable in portal blood and induces differentiation in various human neoplastic cell lines. Earlier reports indicated approximately 20-fold induction in vitro by n-butyrate of the sialyltransferase that catalyzes terminal gly... | US |
The insulin-like growth factor I (IGF I) receptor is a tyrosine kinase-containing transmembrane protein that plays an important role in cell growth control. We have isolated and characterized human genomic DNA clones containing the entire coding sequence of the IGF I receptor. Results of restriction analysis and sequen... | US |
Lipid bodies are non-membrane-bound, lipid-rich cytoplasmic inclusions that occur in many mammalian cell types. Because lipid bodies are more prominent in cells associated with inflammation and are repositories of arachidonyl-phospholipids, a role for lipid bodies in the oxidative metabolism of arachidonic acid to form... | US |
The Ag receptor (TCR) on T lymphocytes has been shown to be specific for foreign antigenic peptides bound to MHC-encoded molecules. During T cell differentiation in the thymus this same TCR mediates the recognition of MHC molecules in the absence of foreign Ag, a process termed positive selection. To analyze the struct... | US |
In addition to its neurotrophic activity, nerve growth factor (NGF) has been shown to interact with cells of the immune system. We have characterized the effects of NGF on human B cell proliferation and the regulation of NGF receptor expression on these cells. Nerve growth factor receptors were expressed on all tonsill... | US |
The phlogistic actions of six molecular species of platelet-activating factor (PAF) (1-O-alkyl-PAF homologs, 16:0-, 18:0- and 18:1-alkyl-PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine (AGEPC) and their respective 1-acyl-PAF analog counterparts, 16:0-, 18:0- and 18:1-acyl-PAF, 1-acyl-2-acetyl-sn-glycero-3-phosphoch... | US |
We previously described a lyophilized supernatant from germinated Candida albicans that blocks human neutrophil (PMN) O2- production and degranulation stimulated by several PMN agonists but does not block stimulation by PMA. In studies to further characterize this Candida hyphal inhibitory product (CHIP), we noted seve... | US |
We have cloned the cDNA for Mo3, an activation Ag expressed by human monocytes and myelomonocytic cell lines after stimulation by PMA, LPS, muramyl dipeptide, certain cytokines, and cAMP agonists. We have previously shown that Mo3 expression in vivo is associated predominantly with macrophages in inflammatory sites. Mo... | US |
Atopic dermatitis (AD) is characterized by a variety of abnormal physiologic and pharmacologic responses in the skin. Leukocyte abnormalities of the cyclic nucleotide system include increased cAMP phosphodiesterase (PDE) and adenylyl cyclase activities. We have evaluated the possibility that a defect of the inhibitory ... | US |
Substance P is a member of a family of structurally related peptides, called tachykinins, that are involved in the regulation of many biologic processes. Diversity in the generation of multiple tachykinin peptides arises due to multiple genes encoding these peptides as well as by mechanisms of alternative RNA processin... | US |
Mls-1 is an endogenous superantigen that leads to in vivo deletion and in vitro stimulation of T cell receptor (TCR) V beta 6-, 7-, 8.1-, and 9-expressing cells. The MA/MyJ mouse deletes the identical set of TCR from its mature T cell repertoire; however, it does not contain Mtv-7, the murine mammary tumor provirus (MM... | US |
Previous work has demonstrated that intergenic V(D)J rearrangement, a process referred to as trans-rearrangement, occurs at an unexpectedly high frequency. These rearrangements generate novel V(D)J combinations which could conceivably have some role in the normal immune system, and since they probably arise through chr... | US |
We have investigated the gating kinetics of calcium channels in the A7r5 cell line at the level of single channels and whole cell currents, in the absence and presence of dihydropyridine (DHP) calcium channel agonists. Although latencies to first opening and macroscopic currents are strongly voltage dependent, analysis... | US |
Simian varicella virus (SVV) causes a varicella-like disease in non-human primates. In this study, SVV virions were purified from SVV-infected BSC-1 cells by zonal and differential gradient centrifugation and the virion polypeptide composition was analysed by SDS-PAGE. SVV virions had a buoyant density of 1.21 g/ml, id... | US |
A selection of human sera were tested for the presence of antibodies that neutralized infectious human papillomavirus (HPV) type 11. Neutralizing antibodies were detected by prevention of HPV-11-induced condylomatous transformation of human foreskin chips transplanted subrenally into athymic mice. Test sera were obtain... | US |
Zinc is necessary for normal membrane function and stability. We postulated that Zn deficiency may disrupt the integrity of the vascular endothelium by decreasing its barrier function. To test this hypothesis, endothelial cells were cultured on polycarbonate filters and exposed to media enriched with either 1% fetal bo... | US |
LP-BM5 MuLV infection of monocyte-macrophages (MM cells) and the ability of MM cells infected with this murine oncornavirus complex to transmit murine acquired immune deficiency syndrome (MAIDS) were assessed. Adherent cells expressing Mac-1 antigen (Mac-1+) were isolated from the peritoneum of infected C57BL/6 mice at... | US |
What is the molecular biological basis of viral pathogenesis in the central nervous system (CNS), ie by what molecular mechanisms do different viruses produce particular patterns of neurological disease in man and animal models, and can one use molecular techniques to ascertain the viral aetiology of certain neurologic... | United Kingdom |
Previous structure-activity relationship studies of CRF have shown that residues 1-4 were not necessary for receptor binding or transduction, that residues 4-8 were important for activation, and that residues 12-41 were mostly responsible for binding. Finally it was proposed that CRF assumed an alpha-helical structure ... | US |
Since the discovery of nerve growth factor (NGF) nearly 40 years ago, extensive studies have elaborated the trophic relationship between a neuron and its end organ. Much evidence has accumulated that depicts the crucial role of neurotrophic factors in determining neuronal survival both during development and after inju... | US |
Experiments were performed which examined the effects of pentobarbital tolerance and dependence on GABAA receptor antagonist binding. In rats implanted with pentobarbital pellets for 7 days, followed by 24 hours of withdrawal, there was a significant decrease in the latency of TBPS-induced seizures and an increase in [... | US |
The gene product of F tral is a bifunctional protein which nicks and unwinds the F plasmid during conjugal DNA transfer. Further biochemical characterization of the Tral protein reveals that it has a second, much lower, Km for ATP hydrolysis, in addition to that previously identified. Measurement of the single-stranded... | US |
The media played a central role in changing the use of aspirin among children with viral illness following reports of its association with a rare but deadly disease, Reye's syndrome (RS). It did so by alerting health professionals and parents about ways to prevent RS in children. Indeed, by the time aspirin product lab... | US |
The ethical controversy surrounding the Centers for Disease Control (CDC) and American Medical Association (AMA) guidelines for restricting the practice of HIV-infected health professionals appears to hinge on whether we give priority to the rights of infected workers or patients. We cannot simply dismiss the concerns ... | US |
Five separate guanine nucleotide-binding proteins (G proteins) were immunologically identified in membranes from neuroblastoma x glioma NG108-15 hybrid cells. These alpha subunit proteins were Gi2 alpha, two isoforms of Gi3 alpha, and two isoforms of Go alpha. The G proteins that interacted with delta-opioid receptors ... | US |
The effects of forskolin (FO) and a water-soluble derivative of FO, L858051 (7 beta-desacetyl-7 beta-[gamma-(N-methylpiperazino)-butyryl] forskolin), were compared on calcium currents (ICa) studied by the whole-cell patch-clamp technique in frog ventricular cardiac myocytes. Both FO and L858051 increased ICa, with half... | US |
Two radical adduct species have been detected in the bile of living rats treated with halothane and phenyl-N-t-butylnitrone (PBN). The treatment of rats with 12% oxygen was required for radical adduct detection. Analysis of the corresponding EPR spectra obtained when deuterated PBN and deuterated halothane or [2-13C]ha... | US |
The adenovirus E1A and E1B proteins are required for transformation of primary rodent cells. When expressed in the absence of the 19,000-dalton (19K) E1B protein, however, the E1A proteins are acutely cytotoxic and induce host cell chromosomal DNA fragmentation and cytolysis, analogous to cells undergoing programmed ce... | US |
The transcriptional activation function of the Saccharomyces cerevisiae GAL4 protein is modulated by the GAL80 and GAL3 proteins. In the absence of galactose, GAL80 inhibits the function of GAL4, presumably by direct binding to the GAL4 protein. The presence of galactose triggers the relief of the GAL80 block. The key ... | US |
High-level expression of a transpositionally competent Ty1 element fused to the inducible GAL1 promoter on a 2 microns plasmid (pGTy1) overcomes transpositional dormancy in Saccharomyces cerevisiae. To investigate the mechanisms controlling the rate of Ty1 retrotransposition, we quantitated transposition and Ty1 gene p... | US |
Behavioral studies implicate the nucleus accumbens (NAcc) as a brain area pivotal for the rewarding effects of opiates like heroine and morphine. Therefore, we studied the effect of a variety of opioids on membrane properties and responses to synaptic stimulation in a slice preparation of the NAcc using intracellular r... | US |
Application of quantitative methods to the study of leishmaniasis epidemiology has allowed Dye (1992) to pinpoint important biological parameters which, if they could be accurately measured in the field, would contribute most to our knowledge of the spread of disease and key targets for control. Three areas in which la... | United Kingdom |
The absorbed dose to water from a 160 MeV proton beam as determined by a flexible, temperature regulated, sealed glass core, water calorimeter was compared to that determined from ionization chambers used in accordance with AAPM Report 16. The ratios of these doses as obtained from two experiments done over four months... | US |
Rats were trained to discriminate the stimulus properties of the benzodiazepine (BZ) receptor antagonist flumazenil using a conditioned taste aversion procedure. On drug trials, fluid-restricted rats were injected with flumazenil (32 mg/kg), given access to a 0.25% saccharin solution for 30 min, and injected with LiCl ... | US |
The cataleptogenic effect of delta 9-THC was compared to its discriminative stimulus effects in rats. The ED50s for the discriminative stimulus and catalepsy were 0.8 and 4.0 mg/kg, respectively, while their time courses were very similar. The ED50 of delta 9-THC for catalepsy in experimentally naive rats was not diffe... | US |
1. We have utilised SH-SY5Y human neuroblastoma cells and primary cultures of rat neonatal cerebellar granule cells, both expressing M3 muscarinic receptors, to examine agonist driven polyphosphoinositide hydrolysis and alterations in intracellular calcium. 2. Stimulation of SH-SY5Y cells leads to a biphasic increase i... | United Kingdom |
Increasing numbers of persons presenting for substance abuse treatment are multiple-substance users and their predominant drugs of choice are cocaine and alcohol. There are similarities in the treatment of alcohol and cocaine abuse, but important clinical differences need to be acknowledged. This chapter compares and c... | US |
The relationships between the patterns of alcohol and cocaine use are examined using information derived from the authors' research data and from the literature. Excessive alcohol drinking was very prevalent among males seeking treatment for cocaine dependence at a Veterans Administration hospital in West Los Angeles. ... | US |
The heterotrimeric guanine nucleotide binding proteins (G proteins) are activated by sensory or hormone receptors. In turn, the G proteins activate effector proteins such as adenylyl cyclase, cyclic guanosine 3',5'-monophosphate phosphodiesterase (cGMP PDE), phospholipase C, and potassium and calcium ion channels by me... | US |
The Ah (dioxin) receptor binds a number of widely disseminated environmental pollutants, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polycyclic aromatic hydrocarbons, and mediates their carcinogenic effects. The ligand-bound receptor activates Cyp 1a1 gene transcription through interaction with specific DN... | US |
Multifunctional calcium-calmodulin-dependent protein kinase (CaM kinase) transduces transient elevations in intracellular calcium into changes in the phosphorylation state and activity of target proteins. By fluorescence emission anisotropy, the affinity of CaM kinase for dansylated calmodulin was measured and found to... | US |
A series of amino-acid substitution mutants has been made with changes in the region of simian virus 40 large tumor antigen (T antigen) that is shared with the small tumor antigen (t antigen). Both single and multiple amino-acid replacements were obtained using the heteroduplex deletion loop method and sodium bisulfite... | US |
Industrial hygiene measurement of exposures to wildland fire fighters was conducted in northern California during three consecutive fire seasons (1986-1989) in conjunction with three separate health effects studies. Chemicals that were monitored included carbon monoxide, total and respirable particulates, polyaromatic ... | US |
Measurements of intracellular Ca2+ ([Ca2+]i) and intracellular Ba2+ ([Ba2+]i) in single AR42J cells were used to evaluate the effect of [Ca2+]i and [Ba2+]i on agonist-evoked [Ca2+]i oscillations. Variations in [Ca2+]i and [Ba2+]i were imposed by gradual activation of entry through voltage-activated Ca2+ channels (VACC)... | US |
We have compared the levels and subtypes of atrial natriuretic peptide (ANP) receptors in astrocyte glial and neuronal cultures prepared from the hypothalamus and brain stem of 1-day-old rats. Astrocyte glial cultures contain approximately twice the number of ANP receptors, as measured by 125I-ANP specific binding, com... | US |
These studies describe the effect of protein kinase C (PKC) activation on the activity of voltage-sensitive L-type Ca2+ channels of GH3 pituitary cells. The rate of 45Ca2+ uptake was stimulated greater than 25-fold by depolarization in the presence of BAY K 8644; the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (... | US |
The depressed functional capabilities of spontaneously hypertensive rat (SHR) muscles, reported previously (Exp. Neurol. 95: 249-264, 1987), may reflect a decrease in muscle responsiveness to catecholamines occurring as a consequence of exposure to the elevated level of plasma catecholamines in SHR. Responsiveness to a... | US |
Certain mouse strains (e.g., DBA/2) contain two renin genes (termed Ren-1 and Ren-2) and express higher renin levels in nonkidney tissues than strains with a single renin gene. The 5'-flanking regions of the Ren-1 and Ren-2 genes contain several TATA boxes preceding putative transcriptional start sites. These initiator... | US |
We investigated whether angiotensin (ANG) II has the potential to regulate expression of genes of the renin-angiotensin system (RAS) in peripheral and central tissues. ANG II (0.1 or 6.0 nmol/h) was infused by osmotic minipump into male Sprague-Dawley rats (225-250 g) for 5 days, either intravenously or intracerebroven... | US |
Although the pathogenetic mechanisms underlying indomethacin-induced mucosal injury remain undefined, the results from recent studies suggest that leukocyte adherence in gastric microvessels may be an important component of this injury process. The objective of this study was to determine whether clinically relevant pl... | US |
Because the gastrin molecule must be alpha-amidated to have maximum biological activity, rat pups from 1 to 6 wk of age were treated with dexamethasone (2 mg.kg-1.day-1) for 3 or 7 days, diethyldithiocarbamate (DDC; 400 mg.kg-1.day-1 x 3 days), dexamethasone and DDC, pentagastrin (750 micrograms.kg-1.day-1), or bombesi... | US |
Evidence is reviewed supporting the view that vitamin A (retinol) and its metabolite, retinoic acid, called natural retinoids, are major factors involved in differentiation and in maturation of the lungs. This conclusion is based on morphological observation that lack of this dietary micronutrient causes keratinizing s... | US |
p-Aminohippurate (PAH) transport in canine tracheal epithelium occurs by a HCO3- -PAH exchange process that is located on the luminal membrane and is inhibited by stilbene derivatives. The effects of increasing concentrations of other organic anions, including probenecid (10-250 microM), dibutyryl adenosine 3',5'-cycli... | US |
Our laboratory has previously described in isolated 1- to 4-mm calf pulmonary arteries, an endothelium-independent contraction to hypoxia that appears to involve the removal of a H2O2-elicited guanosine 3',5'-cyclic monophosphate (cGMP)-mediated relaxation. In this study, we examined the effects of changes in O2 tensio... | US |
We have recently proposed that the actions of endothelin (ET) are in part mediated by opening of chloride channels (K. Iijima, L. Lin, A. Nasjletti, and M. S. Goligorsky. Am. J. Physiol. 260 (Cell Physiol. 29: C982-C992, 1991). In the present study the ability of a chloride channel inhibitor, an indanyloxyacetic acid (... | US |
Apical and basolateral channels were studied in isolated proximal tubule cells of Necturus kidney. Many of these isolated cells maintained their polarity, with clearly delineated apical and basolateral regions. A 20-pS stretch-activated (SA) cation-selective channel was identified at the apical side of these cells. Thi... | US |
This study was designed to improve and validate methods for the accurate and consistent quantitation of angiotensin (ANG) I and II levels in rat kidney and to determine the effects on renal ANG I and II of changes in dietary sodium intake and ANG-converting enzyme (ACE) inhibition. Kidneys from pentobarbital-anesthetiz... | US |
This study begins testing the hypothesis that a causal relationship exists between hypereosinophilia and cardiac dysfunction. Rats infected with the nematode Toxocara canis develop marked hypereosinophilia, with peak blood eosinophil levels of approximately 3,500 eosinophils/mm3 whole blood observed approximately 14 da... | US |
Mesenteric ischemia stimulates both A delta- and C-fiber afferents to reflexly activate the cardiovascular system. Leukotriene B4 (LTB4) concentration is increased in intestinal mucosa following prolonged ischemia (3 h) followed by reperfusion. Because LTB4 sensitizes afferent nerve endings in the skin, we determined w... | US |
One of ethanol's actions after acute exposure is anticonvulsant activity whereas withdrawal from chronic ethanol exposure increases convulsant activity. An increase in neuronal transmission in the GABAergic pathways from striatum to the substantia nigra (SN) and a decrease in GABAergic transmission from SN to superior ... | US |
To investigate whether human immunodeficiency virus type 1 pol gene mutations are selected during prolonged 2',3'-dideoxycytidine (ddC) therapy, we used the polymerase chain reaction to amplify a portion of the reverse transcriptase segment of the pol gene from the peripheral blood mononuclear cell DNA of a patient wit... | US |
The concentrations of doxycycline and 4-de-dimethylaminotetracycline required to inhibit 50% of collagenase activity were found to be 15 to 30 microM for human neutrophil and gingival crevicular fluid collagenases. Fibroblast collagenase was relatively resistant to inhibition by tetracyclines; the 50% inhibitory concen... | US |
The regulation of phosphorylase kinase has been proposed to occur physiologically under conditions of zero-order ultrasensitivity [Meinke & Edstrom (1991) J. Biol. Chem. 266, 2259-2266]. This is also one of the conditions that recent theoretical approaches have indicated to be essential in order for an interconvertible... | US |
The treatment of a B16 melanoma cell line with 2.45-GHz pulsed microwaves (10 mW/cm2, 10-microseconds pulses at 100 pps, 1-h exposure; SAR, 0.2 W/kg) resulted in changes of membrane ordering as measured by EPR (electron paramagnetic resonance) reporter techniques. The changes reflected a shift from a more fluid-like ph... | US |
We performed experiments to investigate subtypes of opioid receptors in the brain involved in the effect of acute (45 min) pulsed microwave exposure (2,450-MHz, 2-microseconds pulses, 500 pps, average power density 1 mW/cm2, peak-power density, 1 W/cm2, average whole body SAR 0.6 W/kg) on cholinergic activity in the ra... | US |
Bilateral infusion of the GABAA-receptor agonist muscimol into the basal forebrain was previously found to impair visual conditional discrimination performance in rats. In order to examine whether the GABAergic input into the basal forebrain is active during performance of this task, the benzodiazepine receptor agonist... | US |
The present study demonstrated that large lesions of the amygdala disrupt the maintenance of reflex facilitation of the unconditioned nictitating membrane (NM) response and slow the acquisition of conditioned NM responses in rabbit. Before behavioral training, the central nucleus of the amygdala and adjacent areas were... | US |
Although neurochemical reductions in cholinergic systems have been found to occur during aging, such changes do not necessarily translate to functional deficits. The cognitive deficits of normal aging have been attributed in part to hypocholinergic function, but anticholinergic hypersensitivity in the elderly has not b... | US |
The present study examined the relative contributions of the amygdaloid basolateral complex (ABL) and central nucleus (CN) to taste-potentiated odor aversion (TPOA) learning--an associative learning task that is dependent on information processing in two sensory modalities. In Experiment 1, rats with neurotoxic lesions... | US |
A series of 4 experiments examined the suggestion (Scoles & Siegel, 1986) that drug-induced place preference conditioning may be due to interference with habituation. In each experiment, rats had the opportunity to select among a drug-paired chamber, a saline-paired chamber, and a novel (or relatively novel) chamber. T... | US |
Young and aged Fischer 344 rats were tested on the place and cue versions of the Morris water maze task. Although all of the young animals reached criterion within the 8-day testing period, the aged animals could be divided into two groups on the basis of their performance to criterion: achievers and nonachievers. Upon... | US |
A profound decrease in activity of the mitochondrial enzyme cytochrome oxidase in blood platelets is a recently identified concomitant of Alzheimer's disease (AD). We investigated a possible pathogenic link between this finding and the symptoms of AD by mimicking this mitochondrial enzyme deficiency in rats. Rats were ... | US |
A series of experiments provided evidence for the existence of a functional opioid system in the fetal rat near term. Application of a tactile probe to the perioral region of the fetus consistently evoked a stereotypic facial wiping response. Administration of low dosages of morphine to the fetus had little effect on n... | US |
Mastoparan is a tetradecapeptide. Mastoparan added to the apical surface of monolayers of Madin-Darby canine kidney (MDCK) epithelial cells, cultured on micropore filters, activated ion transport and increased the permeability of the paracellular pathway across the monolayers. In monolayers of similar MDCK cells in whi... | US |
We studied lung explants in submersion organ culture to examine the role of the developing fetal alveolar epithelium in the production of lung fluid. Fourteen-day-gestation fetal rat lungs were grown in a collagen gel matrix supplemented with F-12 media and 10% fetal calf serum. In this model, the lung continues to gro... | US |
Human cytomegalovirus (HCMV) can infect monocytes and macrophages. The immediate early one (IE1) gene product of HCMV positively regulates its own expression, as well as the expression of the interleukin-1 beta (IL-1) gene. This study describes the IL-1 promoter proximal region required for upregulation of IL-1 gene ex... | US |
Pyrophosphate-dependent 6-phosphofructo-1-kinase (PPi-PFK) from Propionibacterium freudenreichii was inactivated by low concentrations of the lysine-specific reagent pyridoxal phosphate (PLP) after sodium borohydride reduction. The substrates fructose 6-phosphate and fructose 1,6-bisphosphate protected against inactiva... | US |
Excesses of non-Hodgkin's lymphoma have been observed among farmers exposed to phenoxyacetic acid herbicides and, less persuasively, among workers exposed to insecticides. Exposure to organic solvents (particularly chlorinated hydrocarbons) has also been associated with an increased risk of NHL. TCDD (which is a contam... | US |
The effects of captopril on the intrarenal renin-angiotensin system were assessed from measurements in arterial plasma, renal venous plasma, and renal lymph from salt-depleted dogs. In the basal state, immunoreactive angiotensin II (Ang II) in renal venous plasma averaged only 60 +/- 12% (P less than 0.01) of arterial ... | US |
The anterograde spread of herpesvirus in the visual system subsequent to retinitis has been observed clinically. We compared the ability of two well-studied Herpes simplex virus (HSV) strains to be transported in the anterograde direction in the hamster visual system: strain McIntyre, representing HSV-1, and strain 186... | US |
We report the cytogenetic findings in a malignant mixed mullerian tumor of the uterus in a 59-year-old woman. Karyotypic analysis of short-term cultures revealed two abnormal clones of cells characterized by extensive structural and numerical rearrangements. An i(12p) maker chromosome was present in addition to other c... | US |
Loss of heterozygosity studies have been used to identify chromosomal regions which are frequently deleted and thus indicate areas which may harbor tumor suppressor genes. As a result, both the WT1 gene located in chromosome 11p13 and an unidentified gene(s) within chromosome 11p15 have been implicated in Wilms' tumori... | US |
Levamisole in combination with radiation and chemotherapeutic agents is being studied in clinical trials. The mechanism of interaction of levamisole with these modalities is unknown. In order to determine if there is direct interaction between radiation and levamisole, a series of colony-formation assays was performed ... | US |
We have generated mice carrying a mutation of the gene encoding the low affinity NGF receptor p75NGFR by targeted mutation in embryonic stem cells. Mice homozygous for the mutation were viable and fertile. Immunohistochemical analyses of the footpad skin of mutant mice revealed markedly decreased sensory innervation by... | US |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.