Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PD1”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources

Principal cells of cortical collecting ducts of the rat are not a route of transepithelial Cl- transport.

The rat cortical collecting duct (CCD) exhibits high rates of NaCl reabsorption when stimulated by mineralocorticoid and antidiuretic hormone (ADH). The present study was undertaken to determine if there is significant transcellular Cl- movement across the principal cells of the rat CCD. CCDs were dissected from kidneys of rats that had been injected with deoxycorticosterone (5 mg, i.m.) 2-9 days prior to the experiment. The ducts were perfused in vitro with identical perfusing and bathing solutions, except that 200 pmol.l-1 ADH was added to the bathing solutions. The basolateral membrane voltage (PDbl) of principal cells was -77 +/- 1 mV and the luminal membrane voltage (PD1) was -68 +/- 1 mV (mean +/- SEM, n = 124). Separate impalements with single-barrelled Cl(-)-selective microelectrodes gave an apparent intracellular Cl- activity of principal cells of 17 +/- 2 mmol.l-1. Transepithelial PD and PDbl were unaffected by luminal furosemide, hydrochlorothiazide (HCT), 4-acetamido-4-isothiocyanostilbene2,2-disulphonic acid, (SITS), or the Cl- channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB); bath addition of SITS or the Cl- channel blocker diphenylamino-2-carboxylic acid; or replacement of bath HCO3- by Cl-. The intracellular Cl- activity (a(cell)Cl) also remained unchanged with the addition of HCT, SITS or the Cl- channel blockers to either the perfusing or bathing solutions, or with replacement of the bathing solution HCO3-.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorption↗

Pseudodeficiency of arylsulphatase A: strategy for clarification of genotype in families of subjects with low ASA activity and neurological symptoms.

A benign deficiency (pseudodeficiency) of the lysosomal enzyme arylsulphatase A (ASA) (EC 3.1.6.8) towards synthetic substrates complicates the diagnosis of metachromatic leukodystrophy (MLD). The pseudodeficiency is due to a single base substitution in the 3'-untranslated region of the ASA gene (1524+95 A-->G) and it has been reported that this mutation (PD2) always occurs on a chromosome carrying a second mutation in the ASA gene (PD1), which abolishes an N-glycosylation site (N350S). Analysis of the two PD mutations in the ASA gene separately was carried out in a large group of subjects with neurological symptoms and low ASA activity, including close relatives and MLD patients. The relationship between ASA enzyme activity and the different genotypes identified is presented. Evidence for the existence of an allele containing the PD2 mutation alone is presented. A strategy for cases with low ASA activity and neurological symptoms in families carrying a PD allele or both PD and MLD alleles is proposed.

Cerebroside-Sulfatase↗

Isolation and characterization of dibenzofuran-degrading Comamonas sp. strains isolated from white clover roots.

Three dibenzofuran (DF)-degrading strains were newly isolated from roots of white clover ( Trifolium repens L.) and poplar trees grown in DF-contaminated soil samples. These strains, designated KD2, KD7, and PD1, were characterized as Comamonas sp. on the basis of their 16S rDNA sequences and physiological characteristics. The metabolites produced when strain KD7 was incubated with DF were identified by gas chromatography-mass spectrometry (GC-MS) analysis. Interestingly, strain KD7 was found to have two pathways for DF degradation, beginning with angular dioxygenation at carbons 4 and 4a, and lateral dioxygenation at carbons 1 and 2, respectively. Furthermore, strains KD2 and KD7 not only achieved efficient root colonization in clover but also promoted clover growth. They are the first reported Comamonas sp. strains capable of utilizing DF as a sole carbon source. This provides additional information on the diversity of DF-degrading bacteria.

Benzofurans↗

HBcAg-specific CD4+CD25+ regulatory T cells modulate immune tolerance and acute exacerbation on the natural history of chronic hepatitis B virus infection.

Acute exacerbations (AEs) of chronic hepatitis B (CH-B) are accompanied by increased T cell responses to hepatitis B core and e antigens (HBcAg/HBeAg). Why patients are immunotolerant (IT) to the virus and why AEs occur spontaneously on the immunoactive phase remain unclear. The role of HBcAg-specific CD4(+)CD25(+) regulatory T (T(reg)) cells in AE and IT phases was investigated in this study. The SYFPEITHI scoring system was employed to predict MHC class II-restricted epitope peptides on HBcAg overlapping with HBeAg that were used for T(reg)-cell cloning and for the construction of MHC class II tetramers to measure T(reg) cell frequencies (T(reg) f). The results showed that HBcAg-specific T(reg) f declined during AE accompanied by increased HBcAg peptide-specific cytotoxic T lymphocyte frequencies. Predominant Foxp3-expressing T(reg) cell clones were generated from patients on the immune tolerance phase, while the majority of Th1 clones were obtained from patients on the immunoactive phase. T(reg) cells from liver and peripheral blood of CH-B patients express CD152 and PD1 antigens that exhibit suppression on PBMCs proliferation to HBcAg. These data suggest that HBcAg peptide-specific T(reg) cells modulate the IT phase, and that their decline may account for the spontaneous AEs on the natural history of chronic hepatitis B virus infection.

Adolescent↗

The complete amino acid sequence of prolactin from the bullfrog, Rana catesbeiana.

The complete amino acid sequence of prolactin (PRL) from an amphibian species, the bullfrog (Rana catesbeiana), has been determined and conserved residues and domains were analyzed by sequence comparison of PRLs from 15 species of five major vertebrate classes. The bullfrog PRL consists of 197 amino acid residues with three disulfide linkages formed between residues 4-11, 58-172, and 189-197. The bullfrog PRL shows the highest identity with sea turtle PRL (75%); lower identities with chicken PRL (72%), pig, horse, and fin whale PRLs (68%), human, cattle, sheep, and elephant PRLs (60-58%), and rat and mouse PRLs (50%); and significantly lower identity with teleost PRLs (about 30%). It is apparent that all tetrapod PRLs characterized so far contain three disulfide bonds in homologous positions and differ from teleost PRLs which lack the N-terminal disulfide loop. The tetrapod and teleost PRLs share 34 common residues and these conserved residues are clustered in six domains (PD1 to PD6), suggesting that these common residues, or at least part of them, are responsible for the activities common to all PRLs. On the other hand, PD5 is conserved significantly within tetrapod PRLs, but to a lesser extent in teleost PRLs, suggesting that the PD5 contributes to the activities specific to tetrapod PRLs.

Amino Acid Sequence↗

Trigeminal lesions and maternal behavior in Norway rats: II. Disruption of parturition.

Profound deficits in maternal behavior occur following postpartum bilateral infraorbital denervation (IO-X), with substantial recovery 12-24 h later. In the present experiment, primiparous rats were subjected to IO-X or sham surgery on gestation day 22. Whereas parturition behavior was normal in controls, it was severely disrupted in all IO-X dams. Impairments included absent, abbreviated, or delayed perioral behaviors-nest building, participation in delivery, placentophagia, licking and retrieval of pups-accompanied by increased general activity and delayed onset of nursing. There was increased mortality in the litters of IO-X dams at birth and by postpartum day (PD) 3, and impaired retrieval by IO-X dams on PD1-3. A surgery-birth interval of < 7 h vs. > or = 22 h was associated only with poor litter growth. Thus, prepartum IO-X disrupts onset of maternal behavior during parturition, with long-term consequences for offspring well-being.

Animals↗

Histochemical localization of a beta-galactoside-binding lectin and its binding-sites in developing and adult rat cochlea.

The presence of an endogenous rat beta-galactoside-specific lectin (S-Lac) and its specific binding ligands was analyzed, using a rabbit anti-human brain lectin of 14 kDa antibody (anti-HBL-14) and a probe consisting of a biotinylated derivative of the human lectin (HBL-biot) in adult and in developing rat cochleas. At PD1, some epithelial cells of the outer spiral sulcus (OSS) were specifically recognized by the anti-HBL-14 antibody. Then, anti-HBL-14 immunoreactivity progressively appeared in all OSS epithelial cells, and, from PD9 on, it also appeared in inner spiral sulcus (ISS) epithelial cells. Finally, young adult rats exhibited a well defined anti-HBL-14 immunoreactivity in epithelial cells of the inner and outer spiral sulcus. Using the biotinylated probe, from PD3 on, tectorial membrane (TM) and the sensory cells apical surfaces were labelled. The glycoconjugate expression within the developing organ of Corti seems to be highly complex. Lectin was detected in developing and adult epithelial cells surrounding the organ of Corti. In contrast, other glycoconjugates related to B and H human blood group antigens, were transiently present on sensory cells of the organ of Corti. Present findings can be correlated with significant events in development of the cochlea, mainly with cell-cell recognition or cellular adhesion.

Animals↗

Transient expression of estrogen receptor-immunoreactivity (ER-IR) in the layer V of the developing rat cerebral cortex.

Occurrence of estrogen receptor-immunoreactivity (ER-IR) in the cerebral cortex was examined in neonatal and adult rats. In newborn rats of postnatal day 1 (= day of birth) and postnatal day 5 (PD1 and PD5, respectively), ER-IR was not evident in the neocortex. On postnatal days 7, 10 and 13 (PD7, PD10 and PD13 respectively), a group of cells with distinct ER-IR appeared in the layer V of the auditory cortex. At the PD10, weak but specific ER-IR were also appeared in the somatosensory and the visual cortices. Among these areas, the ER-IR positive neurons occurred most frequently in the auditory cortex at PD10 rats. By examination of adjacent sections, one stained with Cresyl violet and the another stained with acethylcholinesterase (AChE) histochemistry, it was revealed that the region with ER-IR at PD7 to PD13 was limited to layer V of the neocortex. These signals, however, disappeared at PD15. In layer II of the neocortex, on the other hand, weak ER-IR signals were detected throughout the area sporadically at PD21 and in adults. The ER-IR detected transiently in the auditory cortex by the antiserum might contribute to maturation and establishment of the neurons of the rat auditory circuit.

Animals↗

Arg-vasopressin content in the suprachiasmatic nucleus of rat pups: circadian rhythm and its development.

To investigate the development of Arg-vasopressin (AVP) content and its diurnal rhythm in the suprachiasmatic nucleus (SCN), AVP was measured by enzyme immunoassay in the rat pup SCN punched out from tissue slices obtained at postnatal day (PD) 1, 5, 10, 12 and 20 from animals maintained under a light-dark cycle (LD). The AVP levels, measured at a restricted time of day, increased from PD1 reaching the adult level at PD10-12. Diurnal rhythm similar to that in adults was evident at PD10-12 under the LD conditions used. The peak value of AVP was observed at the earlier light period, and its trough occurred at the end of the light period. The circadian rhythm remained for 7 days under constant dark (DD) or constant light (LL) conditions. These results indicate that the AVP, one of the output signals from the SCN, starts to oscillate after PD10-12, and shows a free-running rhythm during the nursing period.

Animals↗

The origins of descending projections to the lumbar spinal cord at different stages of development in the North American opossum.

We have employed the retrograde transport of fast blue (FB) to identify the origins of descending projections to the lumbar cord of the opossum from postnatal day (PD)1, 12-13 days after conception, to maturity. When FB injections were made into the lumbar cord at PD1, supraspinal labeling was sparse and limited to the hypothalamus, the reticular formation, the coeruleus complex, the caudal raphe, and, in one case, the interstitial nucleus of the medial longitudinal fasciculus and the lateral vestibular nucleus. Only a few propriospinal neurons were labeled at cervical and thoracic levels. By PD3, however, supraspinal and propriospinal labeling was abundant and present in most of the areas labeled in the adult animal. A notable exception was the red nucleus which was not labeled until approximately PD10. Our results have been compared with those described in other species and discussed in light of their relevance to the development of descending control over hindlimb movement and developmental plasticity of descending spinal pathways.

Amidines↗

Effects of prenatal cocaine on behavioral responses to a cocaine challenge on postnatal day 11.

The purpose of this study was to investigate the effects of prenatal cocaine treatment on behavioral responsivity to a cocaine challenge on postnatal day (PD) 11. Timed-pregnant Sprague-Dawley rats were injected s.c. with 40 mg/kg/day of cocaine (20 mg/kg twice daily) from gestational day 11 to 20. Saline-control females received saline injections and were pair-fed to the cocaine-treated females, whereas untreated-control females were undisturbed and were fed ad lib. Litters were culled to eight pups on PD1 and fostered to normal lactating dams. On PD 11, subjects were given either saline or cocaine (1.25, 2.5, or 5.0 mg/kg s.c.) and then tested 15 min later for isolation-induced ultrasonic vocalizations and other behaviors. Prenatal cocaine-treated pups showed a reduced sensitivity to the stimulating effect of postnatal cocaine on wall climbing, which may reflect an underlying alteration in central dopaminergic and/or noradrenergic systems. Most of the other behaviors studied, including ultrasonic vocalizations, were unaffected by prenatal cocaine administration. However, one other notable finding was an increase in postnatal mortality among the cocaine-exposed pups. We hypothesize that prenatal cocaine treatment may alter pup behavior so as to produce abnormal maternal-offspring interactions and impaired development in some individuals.

Animals↗

The fission yeast ptr1+ gene involved in nuclear mRNA export encodes a putative ubiquitin ligase.

Fission yeast ptr1-1 is one of the mRNA transport mutants that accumulate poly(A)+ RNA in the nuclei at the nonpermissive temperature. We found that the ptr1+ gene encodes a homolog of Saccharomyces cerevisiae Tom1p, a hect type ubiquitin ligase. In ptr1-1, a conserved amino acid in the hect domain of Ptr1p is mutated. The ptr1+ gene is essential for growth and its mutation did not affect nuclear protein export. A ptr1-1 rae1-167 double mutant showed a synthetic effect on a growth defect, indicating that Ptr1p functionally interacts with an essential mRNA export factor Rae1p. We also isolated a multi-copy suppressor for ptr1-1 and found that it is the mpd2+ gene isolated as a multi-copy suppressor of cdc7-PD1.

Active Transport, Cell Nucleus↗

Costimulatory receptors in jawed vertebrates: conserved CD28, odd CTLA4 and multiple BTLAs.

CD28 family of costimulatory receptors is comprised of molecules with a single V-type extracellular Ig domain, a transmembrane and an intracytoplasmic region with signaling motifs. CD28 and cytotoxic T lymphocyte antigen-4 (CTLA4) homologs have been recently identified in rainbow trout. Other sequences similar to mammalian CD28 family members have now been identified using teleost, Xenopus and chicken databases. CD28- and CTLA4 homologs were found in all vertebrate classes whereas inducible costimulatory signal (ICOS) was restricted to tetrapods, and programmed cell death-1 (PD1) was limited to mammals and chicken. Multiple B and T Lymphocyte Attenuator (BTLA) sequences were found in teleosts, but not in Xenopus or in avian genomes. The intron/exon structure of btlas was different from that of cd28 and other members of the family. The Ig domain encoded in all the btla genes has features of the C-type structure, which suggests that BTLA does not belong to the CD28 family. The genomic localization of these genes in vertebrate genomes supports the split between the BTLA and CD28 families.

Amino Acid Motifs↗

The role of leukemia-derived B7-H1 (PD-L1) in tumor-T-cell interactions in humans.

OBJECTIVE: Expression of the B7 homolog B7-H1 (PD1-Ligand) has been proposed to enable tumor cells to evade immune surveillance. Recently, B7-H1 on murine leukemia cells was reported to mediate resistance to cytolytic T-cell destruction. We here investigate the expression and function of the B7 homolog B7-H1 in human leukemia. PATIENTS AND METHODS: Leukemia cells from 30 patients and 9 human leukemia cell lines were investigated for B7-H1 expression by flow cytometry. Functional relevance of B7-H1 for tumor-immune interactions was assessed by coculture experiments using purified, alloreactive CD4 and CD8 T cells in the presence of a neutralizing anti-B7-H1 antibody. RESULTS: Significant B7-H1 expression levels on leukemia cells were detected in 17 of 30 patients and in eight of nine cell lines. In contrast to various other tumor entities and the data reported from a murine leukemia system, no significant inhibitory effect of leukemia-derived B7-H1 on CD4 and CD8 cytokine production (IFN-gamma, IL-2), proliferation or expression of T-cell activation markers (ICOS, CD69) was observed. Furthermore, in the presence of neutralizing B7-H1 antibody (mAb 5H1) occurred no significant changes in T cell IFN-gamma or IL-2 production or proliferation. CONCLUSIONS: Our data demonstrate that leukemia-derived B7-H1 seems to have no direct influence on T-cell activation, proliferation, and cytokine production in humans. Further experiments are warranted to delineate factors and characterize yet-unidentified B7-H1 receptor(s) that determine inhibitory and stimulatory functions of B7-H1 in human leukemia.

Adult↗

Development- and age-associated expression pattern of peroxiredoxin 6, and its regulation in murine ocular lens.

Peroxiredoxin (PRDX) 6 is a unique member of the PRDX family. Its antioxidant and signaling properties are related to its expression level in cells. We studied development- and age-associated changes in PRDX6 expression in the murine lens. We also investigated the effects of dexamethasone (Dex), transforming growth factor-beta1 (TGF-beta1) and tumor necrosis factor-alfa (TNF-alpha) on PRDX6 expression. Expression levels of PRDX6 mRNA in whole lenses isolated from postnatal day (PD) 1- to 18-month-old mice, and the effects of Dex, TGF-beta1 and TNF-alpha on the expression of PRDX6 in lens epithelial cells (LECs), were monitored using real-time reverse transcriptase-polymerase chain reaction (PCR) or Western blot. Localization of PRDX6 was studied using in situ hybridization and immunohistochemistry. PRDX6 expression gradually increased in the lenses of 4-week- to 6-month-old mice and declined thereafter. In situ hybridization and immunohistochemistry revealed that PRDX6 was localized in the cytoplasm of LECs and in lens fibers. Intense PRDX6 staining was present in the whole lens on gestational days 14 and 18. The lenses of PD1 mice showed diminished nuclear fiber staining, while those of 4-week-old mice revealed lack of nuclear fiber staining but intense staining of the germinative zone. LECs treated with TNF-alpha or Dex showed higher PRDX6 expression, while TGF-beta1 down regulated expression. Thus, our results provide a topographic basis for understanding the role of PRDX6 in the lens.

Aging↗

Age- and host-dependent control of Borna disease virus spread in the developing brains of gerbils and rats.

Borna disease virus (BDV) is a non-cytolytic, neurotropic RNA virus that has a broad host range in warm-blooded animals, probably including humans. Recently, we have demonstrated that the neonatal gerbil is a unique model for analyzing BDV-induced acute neurological disease. In this report, to understand the effects of the brain development of gerbils in BDV-induced neuropathogenesis, as well as to investigate the host-dependent differences in BDV propagation and pathogenesis in the brains, we performed experimental infection of BDV using two different infant rodent models, gerbils and rats. We demonstrated here that most of the gerbils infected with BDV on postnatal days (PD) 14, but not on PD1 and PD7, could survive neurological disorders during the observation period of PD85. Interestingly, the levels of BDV RNA and antigen in surviving PD14 inoculated gerbil brains were extremely low, whereas diseased gerbils and both PD7 and PD14 inoculated rats contained significant amounts of BDV antigen in the central nervous system, suggesting that PD14 gerbils successfully controlled BDV spread in the brain. Furthermore, the viral distribution, as well as the expression levels of cytokine and CD8 mRNAs, in the brains was markedly different between the rodent models and between diseased and non-diseased statuses of the gerbils. These results demonstrated that developmentally regulated and host-specific factors could contribute to the prevention of BDV spread in developing animal brains. Studies using different animal systems would provide novel insights into the mechanisms of host defense responses to neurotropic virus infections.

Age Factors↗

Neuronal cell death due to glutamate excitotocity is mediated by p38 activation in the rat cerebral cortex.

Excitotoxic neuronal death occurs through the activation of NMDA and non-NMDA glutamatergic receptors in the CNS. Glutamate also induces strong activation of p38 and indeed, cell death can be prevented by inhibitors of the p38 pathway. Furthermore, intracellular signals generated by AMPA receptors activate the stress sensitive MAP kinases implicated in apoptotic neuronal death, such as JNK and p38. To investigate the relationship between these elements, we have used immunohistochemistry to analyze the expression of GluR2 in the cerebral cortex of postnatal rats (postnatal Day [PD] 8 and 14) after administering them with monosodium glutamate (MSG; 4 mg/g body weight on PD1, 3, 5, and 7). Similarly, the expression of REST, Fas-L and Bcl-2 mRNA transcripts in animals exposed to a p38 inhibitor, SB203580 (0.42 microg/g body weight, administered subcutaneously) was determined by reverse transcriptase-PCR. The enhanced GluR2-expression in the cerebral cortex at PD8 and the down regulation of this receptor at PD14 was correlated with neuronal damage induced by excitotoxicity. In addition, the enhanced expression of REST at PD8 and PD14 suggests that the induction of REST transcription contributes to glutamate-induced excitotoxic neurodegeneration, possibly by modulating GluR2 expression. Fas-L and Bcl-2 over expression at PD8 and their subsequent down regulation at PD14 also suggests that Fas-L could be the direct effector of apoptosis in the cerebral cortex. On the other hand, the presence of Bcl-2 at PD8 could attenuate certain survival signals in neurons under these neurotoxic conditions. Thus, a change in glutamate receptor composition, and enhanced Fas-L and Bcl-2 expression, coupled with activation of the p38/SAPK pathway appear to be events involved in the neuronal apoptosis induced under neurotoxic conditions.

Animals↗

Perinatal cocaine exposure reduces myocardial norepinephrine transporter function in the neonatal rat.

Norepinephrine transporter (NET) mediates the active removal of norepinephrine (NE) released from sympathetic nerve terminals via reuptake, and NET function and expression can be regulated by cocaine. NET expression and its regulation by cocaine in the developing sympathetic nervous system during early postnatal period, however, have not been examined. We quantified immunodetectable NET protein expression in the neonatal rat heart to examine the developmental pattern of myocardial NET during the first 2 weeks after birth. To assess sympathetic innervations, we simultaneously quantified the expression of myocardial tyrosine hydroxylase (TH). Timed pregnant rats received daily intragastric treatment with saline (CTL) or cocaine at 60 mg/kg (Coc) from Gestational Day 2 until parturition. After birth, nursing mothers continued to receive the same treatment. The expression of myocardial TH and NET in neonatal rats were then studied at 1 day (Postnatal Day 1, PD1), 7 days (PD7) or 14 days (PD14) of age. We observed a similar age-dependent increase in the expression for myocardial NET and TH during the first 2 weeks of postnatal life, in both CTL and Coc animals. While myocardial TH was significantly up-regulated following perinatal cocaine exposure, no significant change in immunodetectable myocardial NET protein was evident. To further examine whether NET function might be affected by perinatal cocaine exposure, we performed NE uptake in myocardial membranes from PD14 CTL and Coc rats. We found that NE uptake was reduced at PD14 in the cocaine-treated group. Our results indicate that myocardial NET and TH are both developmentally regulated. Furthermore, our results indicate that perinatal exposure to cocaine did not change NET protein expression but impaired myocardial NET function in the neonatal rat.

Age Factors↗