abstract stringlengths 1 18k | country stringlengths 2 20 |
|---|---|
To define homeo domain subregions that are important for embryonic targeting specificity of homeotic proteins, we generated a series of Deformed/Ultrabithorax chimeric genes in which parts of the Deformed homeo box region were substituted with Ultrabithorax sequences. Chimeric coding regions were attached to heat shock... | US |
Changes in CD45R expression correlate with changes in phenotype in mouse, rat and human T cells. It has been shown in mouse that CD45RB high T cells produce mostly interleukin-2 (IL-2) while CD45RB low T cells produce more IL-4 than IL-2 after mitogen stimulation in vitro. CD45RB expression also decreases when T cells ... | US |
Inbred mouse strains differ in susceptibility to Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease. A strong correlation between disease susceptibility and delayed-type hypersensitivity (DTH) has been previously demonstrated, but no strong correlation between disease susceptibility and total... | US |
Recent data suggest that the increase in ventilation during hypoxia may be related to the release of the excitatory amino acid neurotransmitter glutamate centrally. To further investigate this, we studied the effects of MK-801, a selective noncompetitive N-methyl-D-aspartate receptor antagonist, on the hypoxic ventilat... | US |
The levels of form I and form II ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO) from Rhodobacter sphaeroides were found to depend on the concentration of ammonia supplied to photolithoautotrophically grown cultures. Under conditions in which the cells rapidly depleted the available ammonia, the level of in s... | US |
Purified inactivated form I ribulose 1,5-bisphosphate carboxylase/oxygenase (form I RubisCO) of Rhodobacter sphaeroides was activated by ATP and, to some extent, by other adenylates and nucleotides. Reactivation in the presence of ATP occurred by a time-dependent and concentration-dependent process which appeared to be... | US |
TraC is one of the proteins encoded by the F transfer region of the F conjugative plasmid which is required for the assembly of F pilin into the mature F pilus structure. Overproduction of this protein from the plasmid pKAS2, which carries only traC, resulted in the formation of inclusion bodies from which soluble TraC... | US |
This article reviews the anatomy and neurophysiology of the normal hippocampal formation, with emphasis on the human hippocampus. The hippocampus receives inputs from numerous limbic, cortical, and subcortical areas, primarily via the entorhinal cortex and subiculum. The primary pathway of neural activity entering the ... | US |
1. Postsynaptic responses to spontaneous quantal transmitter release have been compared among neuromuscular junctions in a thin snake muscle. For each junction the type, diameter, and input conductance, G(in) of the postsynaptic muscle fibre were determined. Particularly among fibres of a given type, G(in) was directly... | US |
The expanded lymphocyte population in large granular lymphocyte (LGL)-leukemia carries the phenotypic characteristics of either cytotoxic T lymphocytes (CD3+,CD8+) or natural killer (NK) cells (CD3-,CD15+). In the former subset, clonality has been demonstrated by T-cell receptor gene rearrangement studies. Since NK cel... | US |
These studies examined the effects of reserpine on concentrations of norepinephrine (NE), dopamine (DA) and epinephrine (EPI) and on levels of tyrosine hydroxylase (TH) mRNA in locus coeruleus (LC) and medullary A1 and A2 neurons. Noradrenergic neurons in these regions first were identified by immunocytochemistry and, ... | US |
Temporal changes in tyrosine hydroxylase (TH) mRNA levels in medullary A1 and A2 neurons and locus coeruleus (LC) cells were studied 6, 12 and 24 h following orchidectomy in rats. Brains from intact controls and sham castrated rats also were evaluated at these same time periods. In situ hybridization histochemistry and... | US |
1H magnetic resonance spectroscopic imaging has been used to obtain metabolite maps of the rat brain. The spin-echo-based technique has been evaluated with respect to water and lipid suppression and sensitivity. Metabolite maps were constructed for choline, creatine + phosphocreatine, amino acids, N-acetyl aspartate, a... | US |
Localized 1H NMR spectra at TE = 12 ms were obtained from cerebral cortex of human subjects using ISIS with surface suppression. The 2.29-ppm resonance was assigned to C4 glutamate with contributions from C4 glutamine and GABA using in vivo spectral editing and comparison of chemical shift with pure compounds. The meas... | US |
Recent anatomical data suggest that the nucleus accumbens can be parcellated into a core region, related to the caudate-putamen, and a shell region, associated with the limbic system. We have used pharmacological methods to characterize the dopamine innervations of the nucleus accumbens core and shell in the rat. Conce... | US |
A vaccinia virus-encoded double-stranded RNA-binding protein, p25, has been previously implicated in inhibition of the interferon-induced, double-stranded RNA-activated protein kinase. In this study, we have identified the vaccinia viral gene (WR strain) that encodes p25. Amino acid sequence analysis of a chymotryptic ... | US |
Computer-assisted image analysis was used to demonstrate in exponentially proliferating human tumor cells the uneven postmitotic apportionment of several oncogene-encoded proteins (ras p21; erbB-2 p185; fos p55; myc p62). This observation may provide the explanation for the high degree of heterogeneity of postmitotic c... | US |
The molecular mechanism of C3 deficiency in an Afrikaans patient with recurrent pyogenic infections was studied. Restriction enzyme analysis showed a gene deletion of 800 base pairs (bp) mapping to the alpha chain of C3. Amplification of genomic DNA, using the PCR, demonstrated that the deletion included exons 22 and 2... | United Kingdom |
Primary--i.e., nonsyndromal-postlingual deafness is inherited as an autosomal dominant phenotype in a large kindred in Costa Rica. Genetically susceptible individuals begin to lose hearing at low frequencies at about age 10 years, after language and speaking are learned. Deafness inevitably progresses by age 30 years t... | US |
Two discrete areas of the chick brain, the intermediate medial hyperstriatum ventrale (IMHV) and lobus parolfactorius (LPO), were found to have different functions during the formation of memory for a 1-trial peck-avoidance paradigm. Glutamate, ouabain, and emetine, known to disrupt short-, intermediate-, and long-term... | US |
We develop a mathematical model to account for the complex relationship between drug dose and clinical response in psychopharmacologic research. The model specifies relationships among drug dose, drug bioavailability, pharmacokinetic factors, course moderators, clinical response and the heterogeneity of the disorder, a... | US |
Cases included in a population-based case-control study of breast cancer in men were recruited from 10 geographic areas of the United States from 1983 to 1986. Controls, matched to cases on age and geographic area, were selected by random digit dialing for men under age 65 years and from Health Care Financing Administr... | US |
To determine the modulatory role of the autonomic nervous system on dry air-induced bronchoconstriction (AIB) in the canine lung periphery, we examined the effect of cholinergic, alpha- and beta-adrenergic, and total autonomic ganglionic blockade on AIB. Pretreatment with atropine significantly attenuated AIB by approx... | US |
Experiments measuring epinephrine stimulation of the S49 cell have demonstrated that the rate of adenylate cyclase activation is partly dependent on the rate of turnover of epinephrine occupancy with respect to individual receptors. Specifically, it has been shown that a low occupancy of the full receptor population by... | US |
A new adrenergic antagonist designed for topical use to induce pupillary miosis has been tested for direct toxicity on isolated rabbit corneal endothelium. Dapiprazole hydrochloride was perfused across endothelia in the specular microscope at concentrations from 1.25 micrograms/ml to 1000 micrograms/ml. No toxicity was... | US |
Experiments were performed to obtain more information on the regulation by steroids of catecholaminergic systems in the brain of Japanese quail. Dose-response and time-response experiments were first performed to determine optimal conditions for measuring turnover in the quail brain. The norepinephrine and dopamine tur... | US |
The morphology of somatostatin immunoreactive (SOM-I) neurons in lamina (L) II of the rat spinal cord was determined using a combination of Golgi impregnation and immunohistochemistry. Golgi-impregnated SOM-I neurons that resembled islet, stalked and other cells were observed. Islet cells are considered to be inhibitor... | US |
N-Benzyladriamycin-14-valerate (AD 198) is a highly lipophilic analogue of Adriamycin with novel cytotoxic mechanisms, greater in vivo antitumor activity, and the ability to circumvent multidrug resistance due to P-glycoprotein-mediated drug efflux or decreased topoisomerase II activity. To identify the mechanism(s) wh... | US |
Allelic loss of tumor suppressor genes on chromosome 17p has been implicated in the progression of breast cancer. This is in principle detectable by fluorescence in situ hybridization if the loss occurs by deletion. In order to determine if detectable deletions occur in primary breast cancer, we used dual-color hybridi... | US |
Taxol is a chemotherapeutic drug which acts by stabilizing microtubules, preventing normal mitosis and resulting in a block of the cell cycle at G2 and M. The drug is isolated from the yew, Taxus sp. L., and is currently being evaluated in a series of Phase II and Phase III clinical trials. Taxol blocks cells in the mo... | US |
These studies were designed to investigate the role of P-glycoprotein in an endocrine cell line. Drug-resistant pituitary cells were obtained by growing GH4C1 cells in the presence of increasing concentrations of colchicine. Cells resistant to colchicine at 0.4 micrograms/ml, termed GH4C1/RC.4, exhibited the multidrug-... | US |
Homeobox-containing (HOX) genes are thought to be involved in the regulation of pattern formation and specification of positional information during vertebrate limb development. We report the isolation from a chick limb bud cDNA library of several overlapping chicken HOX cDNAs, which on the basis of their nucleotide an... | US |
We have studied the development and metabolic significance of peroxisomes in the yeast Candida boidinii following adaptation of the organism to cultivation conditions which require the simultaneous presence and activity of two independent peroxisome-mediated pathways for growth. After the addition of methanol to oleic ... | US |
The PRO1 gene of Saccharomyces cerevisiae encodes the 428-amino-acid protein gamma-glutamyl kinase (ATP:L-glutamate 5-phosphotransferase, EC 2.7.2.11), which catalyzes the first step in proline biosynthesis. Amino acid sequence comparison revealed significant homology between the yeast and Escherichia coli gamma-glutam... | US |
A neu/erb B2 ligand growth factor (NEL-GF) was purified to homogeneity from bovine kidney by a procedure involving ammonium sulfate fractionation (35-70% saturation) followed by sequential column chromatography on DEAE-cellulose (DE52), Sulfadex (sulfated Sephadex G-50), heparin-Sepharose 4B, and Superdex 75 (fast prot... | US |
1. The properties of receptors for amino acid neurotransmitters expressed by developing cortical neurons were studied with the use of whole-cell recording in the intact cerebral cortex of embryonic turtles in vitro. The inhibitory agonist gamma-aminobutyric acid (GABA) and the excitatory agonist glutamate were focally ... | US |
The mechanism of gingival overgrowth associated with long-term use of nifedipine and of other drugs that affect calcium homoeostasis, such as cyclosporin and phenytoin, is unknown. With an ultrasensitive assay, we measured the pharmacokinetics of nifedipine in plasma and gingival crevicular fluid (GCF) of nine patients... | United Kingdom |
Hypercalcitoninemia in gastroenteropancreatic tumors associated with calcitonin immunoreactivity is rare. | US |
The lysosomal removal of the sulfate moiety from sulfatide requires the action of two proteins, arylsulfatase A and sphingolipid activator protein-1 (SAP-1). Recently, patients have been identified who have a variant form of metachromatic leukodystrophy which is characterized by mutations in the gene coding for SAP-1, ... | US |
Dexmedetomidine, the highly selective alpha 2-adrenergic agonist, produces a dose-dependent hypnotic response in rats through a central mechanism. Because the locus coeruleus (LC) contains pathways involved in the maintenance of vigilance and a high prevalence of alpha 2 adrenoceptors, we investigated the role of this ... | US |
There is increasing evidence that membrane transporters for glutamine and glutamate are involved in control of liver metabolism in health and disease. We therefore investigated the effects of three catabolic states [starvation (60 h), diabetes (4 days after streptozotocin treatment) and corticosteroid (8-day dexamethas... | United Kingdom |
Despite the growing use of fish in toxicological studies, little is known regarding glutathione (GSH) metabolism and turnover in these aquatic species. Therefore, we examined GSH metabolism in the liver and gills of channel catfish (Ictalurus punctatus), a commonly employed aquatic toxicological model. Treatment of cha... | US |
The only identified component of the scrapie prion is PrPSc, a glycosylinositol phospholipid (GPI)-linked protein that is derived from the cellular isoform (PrPC) by an as yet unknown posttranslational event. Analysis of the PrPSc GPI has revealed six different glycoforms, three of which are unprecedented. Two of the g... | US |
Schizophrenia in late life includes both chronic early-onset schizophrenia and late-onset schizophrenia. Treatment with neuroleptics in relatively low doses is often useful in controlling psychotic symptoms in these patients. The value of neuroleptics is limited, however, by the risks of side effects such as tardive dy... | US |
Endocrine-paracrine cells of the prostate (also known as APUD or neuroendocrine cells) constitute, in addition to the basal and exocrine secretory cells, a third population of highly specialized epithelial cells in the prostate gland. These endocrine-paracrine cells contain, and most likely secrete, serotonin and calci... | US |
1. A novel 1745-dalton pyroglutamyl peptide (BAM-1745)6 was recently isolated and characterized from bovine adrenal medulla chromaffin granules. Its amino acid sequence was found to be 93% identical to residues 580-593 of human chromogranin B (secretogranin I). 2. Based on this sequence a degenerate oligonucleotide pro... | US |
1. Effects of diethyl maleate (DEM) mediated glutathione (GSH) depletion on hepatic and renal cortical blood flow (perfusion), plasma GSH, and portal prostacyclin (6-ketoPGF1 alpha) and thromboxane (TxB2) were determined in anaesthetized swine. 2. Although DEM depleted hepatic GSH to 25% of control, plasma GSH increase... | US |
1. The effects of temperature on the anesthetic potencies of halothane, enflurane and ethanol have been studied in the water flea Daphnia magna. 2. In the absence of anaesthetics, decreasing temperature resulted in decreased activity by the daphnids. 3. Potencies in the gas phase decreased with increasing temperature f... | US |
1. The tetrapeptide FMRFamide which is present in extracts of Nereis virens was localized in various nereid tissues immunohistochemically. 2. Immunoreactive FMRFamidergic cells and fibers were found in the supraesophageal (brain) and subesophageal ganglia, as well as in the intersegmental ganglia of the ventral nerve c... | US |
Patients with suspected reversible airways obstruction (RAO) sometimes report subjective benefit after bronchodilator treatment despite no objective spirometric improvement. One possible explanation for this is improvement in volume-related or plethysmographic parameters in the absence of spirometric improvement. One h... | US |
Microglia and astrocytes produce several cytokines including interleukin 1 (IL1) and tumor necrosis factor alpha (TNF alpha), which have pleiotropic effects in the immune and nervous systems. Recent evidence has come to light that they play a role in damage in the central nervous system. This indeed may be the result o... | US |
Two biosynthetic pathways exist for delivery of membrane proteins to the apical surface of epithelial cells, direct transport from the trans-Golgi network (TGN) and transcytosis from the basolateral membrane. Different epithelial cells vary in the expression of these mechanisms. Two extremes are MDCK cells, that use pr... | US |
Recent evidence has demonstrated that cross-linking class I major histocompatibility complex (MHC) molecules on human T cells with monoclonal antibodies (mAb) triggers T cell activation. The only known natural ligand for MHC class I molecules is CD8. Therefore, the possibility that CD8+ T cells might provide activation... | US |
Previous studies using anti-CD45R monoclonal antibodies (mAb) have shown that normal CD4+ T cells can be separated into virgin and memory cells based on their level of expression of CD45R. CD45Rhi (virgin) T cells secrete interleukin (IL)-2 whereas CD45Rlo (memory) T cells secrete both IL-2 and IL-4. In contrast to the... | US |
We have examined mixed populations and cloned murine CD4+ T cell lines for their sensitivity to anti-CD3-stimulated suicide. The sensitivity of CD4+ clones to anti-CD3-stimulated suicide is independent of their interleukin-2/interleukin-4 or interferon-gamma secretion profile or their lytic efficiency in anti-CD3 redir... | US |
The identity of the neurotransmitter(s) in the mammalian retinogeniculate pathway is unclear. To investigate the possibility that some amino acids and certain dipeptides, such as N-acetyl-aspartyl-glutamate (NAAG), fulfill this function, changes in their concentration were measured in the optic tract, and the parvocell... | US |
We have isolated and sequenced cDNA and genomic clones encoding the alpha and beta subunits of the Neurospora crassa ATP synthase. The genes are not linked to each other: atp-1(alpha) maps to either linkage group I or V, and atp-2(beta) lies on linkage group II. The two genes resemble each other in having a large numbe... | US |
We have previously identified a mutation in the gene for methylmalonyl CoA mutase in a patient with the mut- phenotype of methylmalonic aciduria. This mutation (G717V) interferes with the binding of the deoxyadenosylcobalamin cofactor to the apoenzyme producing a mutant holoenzyme that is defective, but not completely ... | US |
We have previously demonstrated that DNA can be extracted from the dried blood specimen of the type used for newborn screening. The technique presented here allows us to extract RNA from newborn screening specimens for cDNA synthesis by reverse transcriptase and amplification by the polymerase chain reaction (PCR). Pro... | US |
The dynamics of the guanylate cyclase receptor of atrial natriuretic factor (GCA-ANF receptor) were investigated in cultured glomerular mesangial and renomedullary interstitial cells from the rat. In these cells, the GCA-ANF receptor did not mediate internalization and lysosomal hydrolysis of 125I-ANF1-28 and did not u... | US |
The neu protooncogene encodes a tyrosine kinase receptor that is involved in the regulation of normal growth and malignant transformation. To circumvent the use of the incompletely characterized ligand of Neu, we constructed a chimeric protein composed of the ligand-binding domain of the epidermal growth factor recepto... | US |
The role of the alpha-thyroid hormone receptor (TR alpha) in regulation of transcription of the gene for chicken malic enzyme was analyzed in fibroblast cell lines normally unresponsive to triiodothyronine (T3). The gene for this transcription factor was introduced stably and overexpressed using a replication-competent... | US |
This study investigates the role of beta-adrenergic receptors in the immunomodulatory effects of a conditioned aversive stimulus (CS). A CS is an environmental event that is not inherently aversive, but acquires aversive properties through pairings with a stimulus such as electric shock. This study evaluated the effect... | US |
Previous studies have shown that the gold compounds, gold sodium thiomalate (GST) and auranofin (AUR), which are effective in the treatment of rheumatoid arthritis, inhibit functional activities of a variety of cells, but the biochemical basis of their effect is unknown. In the current studies, human T cell proliferati... | US |
The telencephalon in ray-finned fish (actinopterygians) is everted, in contrast to the evaginated telencephalic hemispheres in all other vertebrates. In the more derived ray-finned fish, the teleosts, proliferation of neurons and their migration from the ependymal zone of the pallium renders comparisons between telence... | US |
We have proposed that significant subsets of individuals with IgA deficiency (IgA-D) and common variable immunodeficiency (CVID) may represent polar ends of a clinical spectrum reflecting a single underlying genetic defect. This proposal was supported by our finding that individuals with these immunodeficiencies have i... | US |
We used an adoptive transfer system and CD4+ T cell clones with defined lymphokine profiles to examine the role of CD4+ T cells and the types of lymphokines involved in the development of B cell memory and affinity maturation. Keyhole limpet hemocyanin (KLH)-specific CD4+ Th2 clones (which produce IL-4 and IL-5 but not... | US |
To determine the relative ability of allogeneic endothelial cells to stimulate helper T lymphocytes (HTL), human PBMC or purified T cells were incubated in conventional lymphocyte microcultures or in limiting dilution microcultures with allogeneic human umbilical vein endothelia (HUVE), with cytokine-treated allogeneic... | US |
Candidate AIDS vaccines consisting of recombinant forms of the HIV-1 envelope glycoprotein induce, in seronegative human volunteers, an env-specific T cell response that includes CD4+, MHC class II-restricted CTL capable of lysing HIV-1-infected target cells. In this study, we have analyzed the production of the cytoki... | US |
Leukocytes express a family of high m.w. glycoproteins called leukocyte common Ag (CD45), which are involved in phosphotyrosine signal transduction. Antibodies to different CD45 isoforms distinguish functionally different CD4+ T cell subsets in humans, rats, and mice. Selected protein isoforms are expressed through a p... | US |
The subclassification of alpha-2 adrenergic receptors into A and B subtypes is based on radioligand binding and functional studies. Radioligand binding studies also have suggested the existence of C and D subtypes, which have only been described as binding sites. This study was designed to determine the subtype of prej... | US |
The apical surface of the proximal tubular epithelium is the site of both P-glycoprotein localization and postulated active secretion of organic cations in the mammalian kidney. P-glycoprotein has been shown to act as a pleiotropic drug efflux pump across the cell membrane of tumor cells expressing the multidrug resist... | US |
Earlier investigation of the vascular actions of Neuropeptide Y (NPY) led us to propose that distinct receptors mediated the prejunctional inhibition of periarterial nerve-stimulated norepinephrine (NE) release and the postjunctional potentiation of the increase in perfusion pressure elicited by vasoconstrictors. These... | US |
Cells expressing human immunodeficiency virus type 1 (HIV-1) tat can transactivate the HIV-1 long terminal repeat (LTR) in cocultured T lymphocytes. In this report, we describe the molecular requirements for transcellular activation of the LTR in Jurkat cells. An analysis with deletion mutants and blocking antibodies d... | US |
Human T-cell leukemia virus type 1 (HTLV-1) immortalizes human CD4+ T lymphocytes in culture. Previous studies show that in the context of a herpesvirus saimiri vector, the sequence of the X region at the 3' end of the HTLV-1 genome is also capable of immortalizing CD4+ lymphocytes in the absence of HTLV-1 structural p... | US |
Three of 14 cynomolgus monkeys given the highest dose of an immunosuppressive drug in a 6-month toxicology study developed B virus (Herpesvirus simiae) oral lesions after 3 months of dosing. This necessitated early removal of all high-dose monkeys from the study due to concerns related to B virus. The incidence and sev... | US |
Poxviruses have many useful features as vectors for genes that carry immunising antigens from other viruses, such as ease of production and induction of cellular and humoral immunity, but there is concern about the safety of vaccinia virus. We turned to an avian poxvirus (canarypox); this virus undergoes abortive repli... | United Kingdom |
Identification of laboratory tests that can help predict progression to acquired immunodeficiency syndrome (AIDS) in people infected with human immunodeficiency virus (HIV) is important for clinical management and counselling. We have assessed the usefulness of CD4 lymphocyte count, serum beta 2-microglobulin concentra... | US |
Prophylactic insulin treatment is effective in preventing diabetes in animal models of insulin-dependent diabetes mellitus (IDDM) but the safety of such preventive treatment in prediabetic human subjects remains unclear; insulin is a potential autoantigen that could accelerate beta-cell decompensation and onset of IDDM... | US |
Mutations in the genes encoding the type 1 fimbriae of Salmonella typhimurium were isolated by selecting for the deletion of Tn10 inserted adjacent to the chromosomal fim+ genes and screening for the loss of mannose-sensitive haemagglutination (HA) activity. S. typhimurium strains with Tn10 insertions in ahp were hyper... | US |
We have shown that in embryos treated with ethanol in ovo during days 1-3, a critical period of neuroembryogenesis, cholinergic neuronal phenotypic expression is decreased whereas GABAergic and catecholaminergic neuronal populations are increased as assessed by neuronal markers choline acetyltransferase (ChAT), glutami... | US |
Using restriction fragment length polymorphism (RFLP) analysis, we demonstrated in 4 of 20 patients with astrocytomas loss of heterozygosity on the short arm of chromosome 17 (17p), in the telomeric segment distal to DNA marker pEW301 (locus D17S58). The loss of heterozygosity may uncover a mutation in a tumour suppres... | US |
L-644,711 is a novel anion channel inhibitor which has previously been shown to decrease brain injury in two related rabbit models of cerebral ischaemia. We hypothesize two mechanisms of action of L-644,711 for its salutary effects on cerebral ischaemia: inhibition of neutrophil function and prevention of excitotoxin r... | US |
Recent anatomical and physiological experiments indicate that the nucleus locus coeruleus receives a predominant excitatory amino acid input, as well as a substantial inhibitory input, from the nucleus paragigantocellularis in the ventrolateral medulla. To determine whether C1 adrenergic neurons are involved in the inh... | US |
The effects of serotonin and excitatory amino acids on motoneurons were examined by sucrose gap recordings from the ventral root of the isolated, hemisected frog spinal cord superfused with magnesium-free, carbonate-buffered Ringer solution. Low concentrations of serotonin (0.1 microM) and the serotonin1A agonist 8-hyd... | US |
There is considerable evidence that on the anterior surface of the heart (which is usually supplied by the left anterior descending and the proximal part of the left circumflex coronary arteries), sympathetic efferent reflexes characterized by tachycardia and/or hypertension predominate following experimental or pathol... | US |
In the companion report [Nisenbaum and Berger (1992) Neuroscience 48, 561-578] the contrasting paired impulse responses to stimulation of the corticostriatal pathway which define the Type I and Type II subpopulations of striatal neurons were shown to reflect differential regulation by GABAergic and dopaminergic inputs.... | US |
In adult animals, prolonged beta-agonist exposure leads to down-regulation of beta-adrenergic receptors and desensitization. Prior evidence from our lab suggests that this may not occur in developing animals. To study this, we measured the response to graded epinephrine infusion [2.7, 5.5, 13.6, 27.3 mumol/(kg.min), (0... | US |
Heterotrimeric GTP-dependent regulatory proteins (G-proteins) mediate modulation by many cell surface receptors. Activation of the G-proteins promotes dissociation of their alpha and beta gamma subunits. The similarity of behaviour of beta gamma subunits derived from a variety of G-proteins has led to their use as affi... | US |
The active sites of myosin from skeletal, smooth and scallop muscle have been partly characterized by use of a series of photoreactive analogues of ATP. Specific labelling was attained by trapping these analogues in their diphosphate forms at the active sites by either cross-linking two reactive thiols (skeletal myosin... | US |
Studies of the interaction between actin and myosin subfragment 1 (S1) in solution have shown that the association reaction takes place in at least two steps. Initially the association is relatively weak to form a complex called the A state which can then isomerize to the R state. The rate and equilibrium constants for... | United Kingdom |
Lesions to the dopamine (DA) system in early postnatal development have different behavioral consequences compared to lesions made in adulthood. Intrastriatal injections of the neurotoxin 6-hydroxydopamine (6-OHDA) on the day of birth (PO) or postnatal day 1 (P1) produce a selective supersensitivity to D1 receptor agon... | US |
Activated CD4+ Th2 cells release cytokines (IL-4,-10) that block activation & cytokine (IL-2/IFN-gamma) release by proinflammatory T (CD4+,CD8+) effector cells. To test the hypothesis that peripheral tolerance to alloantigen is linked to differential activation of CD4+ Th2 cells we measured cytokine transcripts in hear... | US |
The initial in vitro observation that cultured keratinocytes, when treated with cytokines such as gamma interferon, increased the binding of T lymphocytes, opened up a whole new avenue of research to understand epidermal trafficking patterns in inflammatory skin diseases. A growing body of data strongly supports the in... | US |
Glutathione (GSH), a major cellular antioxidant, is elevated 2- to 3-fold in kidneys of rats during prolonged treatment with mercury as methyl mercury hydroxide (MMH). Increased renal GSH is accompanied by a dose- and time-related elevation in the relative abundance of mRNA hybridizable to a cDNA probe which encodes re... | US |
DNA sequence analyses of several human immunodeficiency virus (HIV) isolates revealed extensive genetic diversity in the env gene and, to a lesser extent, in other regions of the viral genome, including the long terminal repeat (LTR) sequences. Since the LTRs contain elements responsible for the control of transcriptio... | US |
Previous studies have revealed the presence of pontospinal neurons with either methionine-enkephalin- or tyrosine hydroxylase-like immunoreactivity in the dorsolateral pontine tegmentum of the cat. Using a combined fast blue retrograde transport technique and simultaneous immunofluorescence histochemistry, the present ... | US |
We have investigated the ability of dehydroepiandrosterone (DHEA) to alter the production of interleukin-2 (IL-2) and to bind to a specific binding complex in antiCD3 epsilon activated T cells. Binding activity correlated with the presence of a specific DHEA binding complex in the cytosol and nuclei of DHEA-responsive ... | US |
A microprobe system has been developed that can record Raman spectra from as little as 2 microL of solution containing only micrograms of biological pigments. The apparatus consists of a liquid nitrogen (l-N2)-cooled cold stage, an epi-illumination microscope, and a substractive-dispersion, double spectrograph coupled ... | US |
The purpose of the present study was to determine the confidence with which the small number of 1H NMR nuclear Overhauser effect (NOE) distance constraints measurable across glycosidic linkages in oligosaccharides could be used for solution conformational analysis. This was assessed by use of these constraints in restr... | United Kingdom |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.