Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P30536 (PBS)
 9,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The neural cell adhesion molecule (N-CAM), is expressed in definite spatiotemporal patterns during development. To identify factors that may influence place-dependent n-cam gene expression, we have studied the binding and activation of the n-cam promoter by Pax-8, a member of the Pax family of transcription factors. Pax-8 increased n-cam promoter activity 13.4-fold in cellular co-transfection experiments, and a short segment of the promoter (-143 to -15) mediated the response. This region of the n-cam promoter produced a DNA-protein complex when incubated with either extracts from COS-7 cells transfected with the Pax-8 expression vector or a Pax-8/GST fusion protein. Pax-8 bound to the n-cam promoter through two TGCTCC motifs (designated PBS-1 and PBS-2) that resemble paired domain binding sites. Mutation of PBS-1 and PBS-2 eliminated Pax-8 activation of the n-cam promoter. Transfection of N2A neuroblastoma cells with the Pax-8 expression vector resulted in a 5-fold increase in the transcription of the endogenous n-cam gene. The combined results suggest that Pax-8 activates transcription of the n-cam gene through binding of sequences resembling paired domain binding sites in the n-cam promoter. The data raise the possibility that the n-cam promoter may be regulated by other members of the Pax gene family.
J Biol Chem 1994 Sep 02
PMID:Binding and activation of the promoter for the neural cell adhesion molecule by Pax-8. 807 51

Acid washes are used as an experimental tool to differentiate between cell-surface bound and internalized radioligands. We have observed that washes with acid buffers containing 100 mM acetate can modulate [125I]IGF-II binding to rat C6 glial cells in an unexpected manner: when cells in monolayer culture were prewashed with phosphate buffered saline (pH 7.3) (PBS), [125I]IGF-II binding was characteristic of the IGF-II/mannose-6-phosphate (M6P) receptor. Importantly, IgG 3637, which is purified from an antiserum directed against the rat IGF-II/M6P receptor, blocked binding of [125I]IGF-II whereas nonimmune IgG did not. Affinity crosslinking studies using DSS as the crosslinking agent and Western blotting experiments using antiserum 3637 confirmed the presence of the IGF-II/M6P receptor in C6 glial cells. Prewashes of C6 cell monolayers with acid buffers (pH 4-4.5) which contained 100 mM sodium acetate and which have been used in internalization studies reduced [125I]IGF-II binding by 40-60%. Affinity crosslinking studies using C6 cells showed that the formation of the 250 kDa radioligand-receptor complex was not prohibited by IgG 3637 after acid washes with buffers containing high acetate concentrations, while acid washes with buffers containing no acetate did not cause a loss in the blocking ability of IgG 3637. However, acid washes with 100 mM acetate did not alter the recognition of IGF-II/M6P receptors by IgG 3637 in Western blotting experiments. In addition, in a subset of experiments acid prewashes with acetate also decreased binding of [125I]IGF-I to the IGF-I receptor by 20%. We conclude that acid washes with acetate buffers lead to decreased [125I]IGF-I and [125I]IGF-II binding. In addition, the capability of anti-receptor IgG to block radioligand binding to the IGF-II/M6P receptor also declines. We hypothesize that alteration of ligand binding might be partially caused by perturbation of the cell membrane and hence a conformational change in IGF receptors. These data imply that the use of acetate buffers in acid wash experiments in ligand internalization studies--particularly in studies involving the IGF-II/M6P receptor--should be avoided.
Biochim Biophys Acta 1994 Sep 08
PMID:Perturbation of C6 glial cells by acetate leads to modulation of [125I]IGF-II binding to the IGF-II/M6P receptor: implications for ligand internalization studies. 808 86

Based on previous studies showing that allogeneic islets transplanted into the thymus can induce donor-specific unresponsiveness, we investigated in the nonobese diabetic (NOD) mouse the effect of intrathymic islet isografts on preventing autoimmunity directed against pancreatic islet antigens. Islets prepared from newborn NOD pancreata were injected into one lobe of the thymus of 10- to 11-day-old female NOD mice (experimental group) with no immunosuppression. PBS alone was used for injection into age- and sex-matched litter mates (control group). Thirty of 32 (94%) experimental mice remained normoglycemic for over 30 weeks. Well-formed islets with no indication of insulitis were found in the thymus of these 30 mice, whereas no grafted islets were found in the 2 mice that became diabetic at 17 and 19 weeks, respectively (technical failures). In the control group, 10 of 32 (31%) mice became diabetic between 20 and 29 weeks. This diabetic incidence was, however, lower than that in our colony female mice. In the pancreas of experimental mice, 90.9% of islets were free of infiltrates, whereas only 13.1% of islets were intact in control mice. The spleens of 30-week-old experimental mice contained a slightly higher percentage of CD8+ T cells (P < 0.05) than those of control mice. Cyclophosphamide injections at 30 weeks induced diabetes in 4 of 9 experimental mice. The 2 lines of evidence, (1) marked reduction in insulitis of intrathymic islet-grafted mice and (2) induction of diabetes after treatment with cyclophosphamide, suggest that both thymic clonal deletion and peripheral tolerance may play a role in preventing diabetes.
Transplantation 1993 Sep
PMID:Prevention of overt diabetes and insulitis by intrathymic injection of syngeneic islets in newborn nonobese diabetic (NOD) mice. 821 62

Membrane phospholipid metabolism is abnormal in Alzheimer's disease (AD) brain. Phosphatidylcholine and phosphatidylethanolamine levels are decreased as are choline and ethanolamine, while glycerophosphocholine (GPC) and glycerophosphoethanolamine are increased. To develop a rat model for these changes, we examined the effects of unilateral lesion of the cholinergic nucleus basalis (nBM) with ibotenic acid (10 mg/ml in PBS, 0.5 microliter) and sham lesion on frontocortical phospholipid, choline and GPC. After one week, choline acetyltransferase activity in frontal cortex was decreased (26%, p < 0.005, n = 14) on the nBM ibotenate-lesion side relative to the contralateral side, while there were no differences following the nBM sham-lesion. Levels of membrane phospholipids (nmol/mg protein) in adjacent frontal cortex sections exhibited concomitant decreases (13%, p < 0.05, n = 14) on the nBM ibotenate-lesion side, while there were no differences following the nBM sham-lesion. Tissue nBM ibotenate-lesion frontocortical choline and GPC levels were also decreased relative to those in control tissue (choline: 21%, p < 0.05, n = 14; GPC: 10%, p < 0.05, n = 14), while nBM sham-lesion showed no effect. Muscarinic receptor sensitivity in frontal cortex following nBM ibotenate-lesion was increased, as measured by carbachol-stimulated inositol phosphate production (p < 0.001, n = 12), indicating that increased receptor mediated phospholipid hydrolysis in cortex may occur following nBM ibotenate-lesion. These data suggest that impaired cholinergic transmission alters phospholipid metabolism in cholinergic target regions.
Ann N Y Acad Sci 1993 Sep 24
PMID:Phospholipid and phospholipid metabolites in rat frontal cortex are decreased following nucleus basalis lesions. 823 90

The removal of protein-bound substances of pathogenetic relevance from blood is of therapeutic interest for drug intoxications, renal and liver failure, and metabolic disorders. Current methods using adsorbents are effective but often not specific enough. This work presents an alternative method that enables the dialyzability of albumin-bound toxins from plasma by the use of a high-flux dialyzer (F 60 Fresenius) and an albumin solution circulating on the dialysate side to increase selectively the affinity for albumin-bound toxins. This method resulted in effective removal of unconjugated bilirubin, drugs with a high protein-binding ratio (sulfobromophthalein, theophylline), and a protein-bound toxin (phenol). The additional removal of PBS could extend the applicability of dialysis, for example, to drug intoxications and liver failure or could improve the elimination of protein-bound uremic toxins in chronic renal failure.
Artif Organs 1993 Sep
PMID:Dialysis against a recycled albumin solution enables the removal of albumin-bound toxins. 824 75

The placenta is a rich source of immunocompetent cells. We have studied the phenotype, number and origin of placental mononuclear blood cells isolated from 32 normal term placentae using 4 color flow cytometry. Respective maternal and cord blood leucocyte preparations were also compared. Placental tissue without extraembryonic membranes was cut into small pieces and divided. One portion was washed extensively with ice-cold PBS. Both tissue portions were disrupted in a blender and cells were dissociated by using a 180 mu sieve. Leucocytes were isolated by Ficoll-Hypaque density gradient centrifugation. Maternal and cord bloods were HLA typed and in cases of HLA-A2 or B7/40 disparity, monoclonal anti-HLA antibodies to these antigens showed that unwashed placental tissue contained 35% maternal and 65% fetal cells. This ratio, however, was not reflected for a given cell phenotype. In comparison, washed placental tissue contained cells of fetal origin only. Both unwashed and washed placental tissue contained fewer CD3 and CD4, but more CD8 cells than maternal and cord blood. Markers of NK cells such as, CD16, CD56, and CD57 showed this cellular phenotype to be 15 times more abundant in the placental preparations than in cord and maternal blood. The quantitative differences between peripheral blood and placental CD8 and NK cells were further explored with an antiprogesterone receptor antibody in combination with anti-CD8, anti-CD57 and anti-HLA-DR. The number of progesterone receptor (PGR) positive cells was three times higher in placental tissues than in cord or maternal blood. These data indicate that the phenotypic frequencies of certain placental leucocytes are significantly different from maternal and fetal peripheral blood. Progesterone and the presence of PGR may be important in the differential retention of placental leucocytes.
J Reprod Immunol 1993 Sep
PMID:Phenotypic characterization of normal human placental mononuclear cells. 827 Dec 37

The aim of this study was to examine the effects of biglycan, a small chondroitin sulfate proteoglycan with neurotrophic activity, on memory and reinforcement upon unilateral injection into the region of the nucleus basalis magnocellularis (NBM). In experiment 1, rats with chronically implanted cannulas were injected with biglycan and tested on the uphill avoidance task, which involves punishment of a high-probability turning response on a tilted platform (negative geotaxis). Immediately after the training trial, that is, after a tail-shock was administered upon performing the response, rats received one microinjection (0.5 microliter) of substance P (SP) in a reference dosage of 0.74 pmol or biglycan (doses ranging from 1.3 to 1300.0 nmol) into the NBM region. When tested 24 h later, rats treated with SP (0.74 pmol) or biglycan (2.1 and 2.6 nmol) had significantly longer uphill latencies than vehicle (PBS) controls, indicative of superior learning of the avoidance response. In experiment 2, a test for possible proactive effects of post-trial biglycan on performance during the retention trial was performed. Furthermore, the uphill avoidance task was combined with a conditioned place preference task to assess possible reinforcing effects of biglycan. Rats were injected with either 2.6 or 130.0 nmol biglycan immediately after the training trial of the uphill task. One control group received 2.6 nmol biglycan 5 h after the trial, a second group was sham-operated. Additional groups were included which received biglycan (2.6 or 130.0 nmol), SP (0.74 pmol) or PBS after the training trial but no tail-shock.(ABSTRACT TRUNCATED AT 250 WORDS)
Behav Brain Res 1995 Sep
PMID:Facilitation of learning following injection of the chondroitin sulfate proteoglycan biglycan into the vicinity of the nucleus basalis magnocellularis. 851 29

Nucleocapsid protein NCp10 of murine leukemia virus (MuLV) is encoded by the 3' domain of gag and contains a zinc finger of the form Cys-X2-Cys-X4-His-X4-Cys flanked by basic amino acids. In the course of virus assembly, NCp10 is necessary for core formation, and the zinc finger flanked by the basic residues is required for the packaging of the genomic RNA dimer. In vitro, NCp10 exhibits strong nucleic acid binding and annealing activities that appear to be critical for virus infectivity since NCp10 promotes dimerization of the viral RNA containing the E/DLS packaging-dimerization signal and annealing of replication primer tRNA(Pro) to the initiation site of reverse transcription (PBS). Recent in vitro studies have suggested that NCp10 may also play a role in proviral DNA synthesis. To investigate the function of NCp10 in proviral DNA synthesis in vivo, we developed a simple and convenient genetic packaging system consisting of two DNA constructs expressing the packaging components gag-pol and env of Friend MuLV and a Moloney MuLV-based lacZ vector with either the MuLV E+ or a rat VL30 E packaging signal. This system allowed us to examine the consequences of a set of mutations in NCp10 on a single round of recombinant virus replication. Most mutations in the N- or C-terminal domain of NCp10 do not significantly alter infectivity, while those in the zinc finger drastically impair infectivity. Analysis of the viral RNA content in virions showed that all mutations in the zinc finger decrease but do not abolish packaging of the recombinant genome. Interestingly enough, mutation of Y-28 to S (mutation Y28S) in the zinc finger results in RNA packaging at a level similar to that observed upon deletion of three prolines and three arginines in the C-terminal domain of NCp10 (mutant delta PR3). However, mutant Y28S is noninfectious while mutant delta PR3 is only threefold less infectious than the wild-type virus, which prompted us to examine the role of NCp10 protein in proviral DNA synthesis in vivo using these nucleocapsid mutants. PCR amplification was used to analyze viral DNA synthesized in newly infected cells, and results indicate that the Y28S zinc finger mutation impairs reverse transcription, thus suggesting that the nucleocapsid protein zinc finger plays a key role in proviral DNA synthesis in vivo.
J Virol 1996 Sep
PMID:The zinc finger of nucleocapsid protein of Friend murine leukemia virus is critical for proviral DNA synthesis in vivo. 870 95

We report that acetyl-N-Ser-Asp-Lys-Pro (AcSDKP), which removes progenitor cells from cell cycle, in combination with granulocyte-colony stimulating factor (G-CSF) can significantly improve myelorestoration following irradiation (7 Gy). Peripheral blood, spleen and bone marrow (BM) cell recovery and progenitor cell reconstitution [IL-3-responsive colony-forming cells (CFC) and high proliferative potential colony-forming cells (HPP-CFC)] were studied. Studies on the optimal schedule of AcSDKP administration revealed maximal effects on progenitor cells when AcSDKP was administered as a continuous infusion for 3 d starting 24 h prior to irradiation and used in combination with G-CSF. The numbers of CFC and HPP-CFC in the BM were significantly increased following irradiation in mice receiving AcSDKP and G-CSF as compared to either drug alone. The numbers of CFC in the spleen were significantly increased in mice receiving AcSDKP and G-CSF on days 10 and 14 as compared to AcSDKP alone, but not G-CSF. Similarly, CFC and HPP-CFC in the spleen were significantly increased in mice receiving AcSDKP and G-CSF on day 18 as compared to mice receiving PBS and G-CSF. These studies suggest that AcSDKP in combination with G-CSF may have potential for the protection of progenitor cells in patients undergoing intensive chemo- and/or radiotherapy.
Br J Haematol 1996 Sep
PMID:In vivo haemoprotective activity of tetrapeptide AcSDKP combined with granulocyte-colony stimulating factor following sublethal irradiation. 882 83

Effects of FSH on ovarian follicular development can be modulated by factors present in serum or by locally produced factors in follicular fluid. Some of these factors may act directly on the FSH receptor. A Chinese hamster ovary cell line (CHO-F3B4) stably transfected with the human FSH receptor has been used to measure the effects of these modulators on FSH-stimulated adenylate cyclase activity. After incubation of CHO-F3B4 cells with human recombinant FSH (recFSH) for 4 h, cAMP levels were elevated 100-230 times above basal levels (ED50 24.9 mU/ml recFSH). cAMP production was inhibited after the addition of increasing amounts (up to 90% of the incubation volume) of hypogonadotrophic human serum (HS) at a fixed stimulatory dose of 30 mU/ml recFSH. At 10% HS the cAMP response was diminished to approximately 40-60% of the original value, whereas at a concentration of 90% HS the cAMP values were diminished to 30%. Effects of serum components on cell viability could be excluded, since forskolin- and cholera-toxin-stimulated cAMP production were not affected by preincubation of the cells in the presence of HS. The FSH-stimulated oestradiol production in rat Sertoli cells, which has been used frequently for in vitro bioassays of FSH, was almost completely inhibited by the addition of human serum, suggesting that serum has more pronounced effects on events downstream of receptor activation. Various specific FSH binding inhibitors have been demonstrated by radioreceptor assays to be present in serum. In order to assess whether such FSH receptor binding inhibitors would also inhibit receptor activation, the specific conditions used in the radioreceptor assays (buffers of low ionic strength) were also used to measure the effects of serum on FSH receptor activation. Under these conditions (a low-salt buffer, corrected for low osmolarity with 200 mM sucrose), CHO-F3B4 cells responded to FSH stimulation in a similar way to that observed in normal buffers. When CHO-F3B4 cells were incubated in this low-salt buffer with a fixed low dose of FSH (3 mU/ml), the addition of 3-90% (v/v) dialysed HS inhibited the FSH-stimulated cAMP accumulation to a similar extent to that in standard conditions. The observed inhibition of adenylate cyclase activation by the low-molecular-mass fraction (< 10 kDa) of HS could be attributed to the presence of salts in this fraction, since the addition of PBS in similar concentrations displayed an equal degree of inhibition. It is concluded that the inhibitory effects of serum on FSH-stimulated cAMP production in CHO-F3B4 cells are small, compared with the inhibition of aromatase induction in rat Sertoli cells. The strong inhibition of aromatase in rat Sertoli cells may result from the effects of serum acting on the FSH receptors as well as on other pathways not related to the FSH receptor. Therefore, measurement of aromatase in Sertoli cells is not suitable for the detection of inhibitors of FSH receptor activation. The CHO-F3B4 cells are useful for the measurement of whether inhibition of FSH receptor activation occurs in serum or follicular fluid from patients with disturbed follicle development.
J Endocrinol 1996 Sep
PMID:Application of a CHO cell line transfected with the human FSH receptor for the measurement of specific FSH receptor activation inhibitors in human serum. 888 70


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