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J Zhou

Publications and source records attributed to J Zhou.

At least 55 records · Page 3Linked to original sources
PubMed2005

Possible association of the MAG locus with schizophrenia in a Chinese Han cohort of family trios.

Neurotransmitter-based hypotheses have so far led to only moderate success in predicting new pathogenetic findings in etiology of schizophrenia. On the other hand, the more recent oligodendroglia hypotheses of this disorder have been supported by an increasing body of evidence. For example, the expression level of the myelin associated glycoprotein (MAG) gene has been shown to be significantly lower in schizophrenia patient groups compared to control groups. Such an effect might be a result of genetic variations of the MAG gene. In order to test this hypothesis, we genotyped four markers within the MAG locus in 413 trios sample of the Han Chinese using allele-specific PCR. None of the four markers revealed noticeable allelic significance. However, the four-marker and two-marker haplotypes covering components rs720309 and rs720308 were observed to be significantly associated with schizophrenia (P < 0.0001) in this study. In addition, we identified one common risk haplotype TA (rs720309-rs720308, present in 78.5% of the general population) that showed increased evidence of overtransmission from parents to affected offspring (P = 0.0001). The results demonstrated MAG might play a role in genetic susceptibility to schizophrenia. Furthermore, our finding of a possible association between the MAG locus and schizophrenia is in agreement with the hypotheses of oligodendrltic and myelination dysfunction.

Adult↗
PubMed2005

FK506 enhances triptolide-induced down-regulation of cyclooxygenase-2, inducible nitric oxide synthase as well as their products PGE2 and NO in TNF-alpha-stimulated synovial fibroblasts from rheumatoid arthritic patients.

OBJECTIVE: To explore the effects of FK506 on the inhibition of cell proliferation and the expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) and their products PGE subset2 and NO in TNF-alpha-stimulated human rheumatoid arthritis synovial fibroblasts (RASF) treated with triptolide (TP), and to study the mechanisms involved when combining FK506 and TP in RA therapy. MATERIALS AND METHODS: RASF used in the experiments were obtained from the synovial tissue of patients with RA before being cultured. RASF were pretreated with FK506 (10 approximately 1000 nM) for 2 hours before being stimulated with TNF-alpha (20 ng/ml) in the presence or absence of TP (10 ng/ml) . RASF proliferation was determined by [3 supersetH]-TdR incorporation. Production of PGE subset2 and NO in culture supernatants of RASF was detected by competitive ELISA and enzymatic reduction of nitrate, respectively. Expressions of COX-2 and iNOS mRNA in RASF were analyzed by semi-quantitative RT-PCR. Expressions of COX-2 and iNOS protein were estimated by Western-blot and a cellular enzyme immunoassay. NFkappaB activity in whole-cell extract of treated RASF was also measured using an ELISA-based method. RESULTS: Neither FK506 nor TP at a lower concentration (10 ng/ml) affected TNF-alpha-induced COX-2 and iNOS expressions or PGE subset2 and NO productions in synovial cells. Combined treatment of FK506 and a lower concentration of TP (10 ng/ml) reduced both COX-2 and iNOS mRNA and protein expression, and correspondingly reduced PGE subset2 and NO produced by synovial fibroblasts. This effect was highly correlated with FK506 concentration (10 approximately 1000 nM). NFkappaB activity in TNF-alpha-stimulated synovial cells was suppressed more profoundly by FK506 plus TP (10 ng/ml) than by TP (10 ng/ml) alone. However, no change was observed regarding the inhibition of synovial cell proliferation after combined treatment of FK506 and TP. CONCLUSION: FK506 enhanced TP-mediated down-regulation of COX-2 and iNOS as well as their products PGE subset2 and NO in human TNF-alpha-stimulated RASF by more profoundly suppressing the activity of NFkappaB.

Arthritis, Rheumatoid↗
PubMed2005

Rapid non-genomic inhibitory effects of glucocorticoids on human neutrophil degranulation.

BACKGROUND: Glucocorticoids acting as anti-inflammatory or immunosuppressive drugs have been shown to exert most of their effects genomically. Recent findings suggest that non-genomic activity might be relatively more important in mediating the therapeutic effects of high-dose pulsed glucocorticoid. However, few non-genomic anti-inflammatory effects were reported, much less non-genomic mechanisms. OBJECTIVE: This study was performed to investigate the nongenomic effects of glucocorticoids on human neutrophil degranulation. METHODS: Purified human neutrophils were pretreated with 6 alpha-methylprednisolone or hydrocortisone for 5 min, and then primed with N-formyl-methionyl-leucyl-phenylalanine (fMLP) (10(-6) M) or phorbol myristate acetate (PMA) (50 ng/ml) in the presence of cytochalasin B. The release of two markers of neutrophil granules, lactoferrin and myeloperoxidase, was measured by ELISA and enzymology methods respectively. RESULTS: Both 6 alpha-methylprednisolone (10(-5)-10(-4) M) and hydrocortisone (10(-4) M) showed significant inhibitory effects on neutrophil degranulation within 5 min after fMLP administration. For PMA stimulated degranulation, 6 alpha-methylprednisolone (10(-4) M) showed significant inhibitory effects (p < 0.01), while hydrocortisone (10(-4) M) only showed an inhibitory tendency (P > 0.05). Neither RU486 (10(-5) M) nor cycloheximide (10(-4) M) could alter the inhibitory effects of glucocorticoids. CONCLUSION: Our results demonstrate that megadoses of glucocorticoids exert rapid inhibitory effects on human neutrophil degranulation at the cellular level via a new mechanism that is independent of corticosteroid type II receptor occupation or protein synthesis. We infer that these effects may be very important when glucocorticoids act as anti-inflammatory drugs during pulse therapy.

Cell Degranulation↗
PubMed2005

Effect of load and temperature on in vitro degradation of poly(glycolide-co-L-lactide) multifilament braids.

The effects of load and temperature on in vitro degradation behaviors of poly(glycolide-co-L-lactide) 90/10 multifilament braids were investigated in phosphate buffer solution at pH 7.4. The property changes of the braids with time were monitored by tensile test, gel permeation chromatography analysis, and scanning electron microscopy. The interrelationships between material properties, time and experimental conditions were explored. The results showed that the polymer braids gradually lost their strength and molecular weight with the increasing in vitro time. While the load levels applied had no effect on the materials, raising temperatures significantly accelerated the degradation. It was found that for a given tensile breaking strength retention (BSR), the dependence of degradation time on temperature could be illustrated by an Arrhenius-type equation, from which the activation energy could be derived. Further analysis indicated that there are well-defined relationships between molecular weight, BSR and breaking strain retention, and these relationships can be illustrated mathematically. Finally, the surface morphology of the fiber showed visible change during the degradation process.

Absorbable Implants↗
PubMed2005

Magnesium supplementation prevents chronic cyclosporine nephrotoxicity via adjusting nitric oxide synthase activity.

INTRODUCTION: Nitric oxide synthase (NOS) is a protective factor for chronic cyclosporine nephrotoxicity by virtue of adjusting the production of nitric oxide (NO). The aim of this study was to explore the role of NOS in the effect of magnesium supplementation to prevent chronic cyclosporine nephrotoxicity. METHODS: Rats maintained on a low-salt diet were divided into three groups: normal controls, cyclosporine group (CsA 15 mg x kg(-1) x d(-1) subcutaneously) and CsA + Mg2+ group (CsA subcutaneously and dietary supplementation with 0.6% Mg enriched by MgCl2). On day 28, plasma Mg2+, plasma creatinine, NOS activity, and NO content in renal tissue were examined. The renal expression of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) in kidneys was determined by an immunohistochemistry technique. The lesions of chronic cyclosporine nephrotoxicity were identified by HE and PAS stains as well as electron microscope. RESULTS: After 28 days of CsA administration, characteristic histological lesions of chronic cyclosporine nephotoxicity were observed, including arteriolopathy, tubular atrophy and interstitial fibrosis. Giant mitochondria and microcalcifications were observed by electron microscopy. Simultaneously, constitutive nitric oxide synthase (cNOS) activity in kidneys was increased, but NO content did not increase correspondingly (P < .05) compared with normal controls. Dietary supplementation with Mg2+ ameliorated the CsA-induced histological lesions. cNOS activity was decreased to normal levels and NOS was increased (P < .05) compared with animals that only received CsA. CsA and magnesium supplementation did not change iNOS activity. CONCLUSIONS: Dietary supplementation with Mg2+ seems to improve renal function and almost abolish CsA-induced histological lesions via altering the abnormal activation of cNOS in this model.

Animals↗
PubMed2005

Continuous transcatheter arterial thrombolysis for early hepatic artery thrombosis after liver transplantation.

Early hepatic artery thrombosis (HAT) after orthotopic liver transplantation remains a significant cause of graft loss and patient death. The most effective treatment approach is still controversial. The purpose of this study was to assess the effect of continuous transcatheter arterial thrombolysis in the treatment of early HAT. Routine posttransplant color Doppler imaging (CDI) was performed to monitor hepatic artery blood flow. HAT was confirmed by arterial angiography in suspected cases. HAT was identified in 8 patients (8/287, 2.8%) which occurred on days 2 to 19 (mean, 5.2 days) after liver transplantation. Patients with HAT were treated with continuous transcatheter arterial thrombolysis using urokinase. Successful revascularization through thrombolysis was obtained in all eight cases. One patient died of a pulmonary infection at 2 months after liver transplantation. Another patient underwent retransplantation because of resistant allograft rejection and recurrence of HAT 6 months after the first operation, but died from multiple system organ failure 2 months later. The other six patients remained in good health during the follow-up period of 3 to 27 months. Our results demonstrate that CDI is an effective method to monitor the occurrence of early HAT after liver transplantation. Furthermore, continuous transcatheter arterial thrombolysis with urokinase could be a rational therapeutic approach to rescue the allograft following early HAT diagnosis confirmed by arterial angiography.

Adult↗
PubMed2005

Development of a practical immunochromatographic test with recombinant P50 for the diagnosis of Babesia gibsoni infection in dogs.

An immunochromatographic test (ICT), using recombinant truncated P50 (P50t), for the detection of antibodies to Babesia gibsoni was developed and evaluated. Whereas all sera from specific pathogen-free dogs were clearly negative, all sera from dogs experimentally infected with B. gibsoni were clearly positive in the ICT. In addition, the ICT detected no cross-reactivity with sera from dogs experimentally infected with closely related parasites, B. canis canis, B. canis vogeli, and B. canis rossi, or with Neospora caninum, and Leishmania infantum. Sequential sera from a dog experimentally infected with B. gibsoni were tested with the ICT; it was shown that the specific antibodies are detectable as early as 6 days post-infection (p.i.) and that strong antibody responses remained until the end of the experiment (144 days p.i.). To evaluate the clinical application of the ICT, a total of 54 serum samples collected from domestic dogs that had been identified as having signs of anaemia at veterinary hospitals in Japan, were tested with the ICT, the previously established enzyme-linked immunosorbent assay (ELISA) and with the indirect fluorescent antibody test (IFAT). Twenty-four of the tested samples (44.4%) were positive in both ICT and ELISA, and (51.8%) in IFAT. The concordance between ELISA and ICT was found to be 100%, and 85.7% with IFAT. Taken together, the results above suggest that the ICT using P50t is rapid, simple, accurate, and suitable for use at clinical sites for the diagnosis of B. gibsoni infection in dogs.

Animals↗
PubMed2005

A genome-wide scan for quantitative trait loci linked to obesity phenotypes among West Africans.

OBJECTIVE: To identify quantitative trait loci (QTL) for three obesity phenotypes: body mass index (BMI), fat mass (FM) and percent body fat (PBF) in West Africans with type 2 diabetes (T2DM). DESIGN: An affected sibling pair (ASP) design, in which both siblings had T2DM. Obesity was analyzed as a quantitative trait using a variance components approach. SUBJECTS: Sib-pairs affected with T2DM from the Africa America Diabetes Mellitus (AADM) study, comprising 321 sibling pairs and 36 half-sibling pairs. MEASUREMENTS: Weight was measured on an electronic scale to the nearest 0.1 kg, and height was measured with a stadiometer to the nearest 0.1 cm. Body composition was estimated using bioelectric impedance analysis (BIA). Genotyping was carried out at the Center for Inherited Disease Research (CIDR) with a panel of 390 trinucleotide and tetranucleotide repeats. RESULTS: The obesity-related phenotype showing the strongest linkage evidence was PBF on chromosome 2 (LOD 3.30 at 72.6 cM, marker D2S739). Suggestive linkage to FM was found on chromosomes 2 (LOD 2.56 at 80.4 cM) and 5 (LOD 2.25 at 98 cM, marker D5S1725). The highest LOD score for BMI was 1.68 (chromosome 4, 113.8 cM). The areas of linkage for the three phenotypes showed some clustering as all three phenotypes were linked to the same regions of 2p13 and 5q14, and our study replicated linkage evidence for several regions previously reported in other studies. CONCLUSION: We obtained evidence for several QTLs on chromosome 2, 4 and 5 to three obesity phenotypes. This study provides data on the genetics of obesity in populations that are currently under represented in the global effort directed at understanding the pathophysiology of excess adiposity in free living individuals.

Adipose Tissue↗
PubMed2005

Genetic segregation of spontaneous erosive arthritis and generalized autoimmune disease in the BXD2 recombinant inbred strain of mice.

The BXD2 strain of mice is one of approximately 80 BXD recombinant inbred (RI) mouse strains derived from an intercross between C57BL/6J (B6) and DBA/2J (D2) strains. We have discovered that adult BXD2 mice spontaneously develop generalized autoimmune disease, including glomerulonephritis (GN), increased serum titres of rheumatoid factor (RF) and anti-DNA antibody, and a spontaneous erosive arthritis characterized by mononuclear cell infiltration, synovial hyperplasia, and bone and cartilage erosion. The features of lupus and arthritis developed by the BXD2 mice segregate in F2 mice generated by crossing BXD2 mice with the parental B6 and D2 strains. Genetic linkage analysis of the serum levels of anti-DNA and RF by using the BXD RI strains shows that the serum titers of anti-DNA and RF were influenced by a genetic locus on mouse chromosome (Chr) 2 near the marker D2Mit412 (78 cm, 163 Mb) and on Chr 4 near D4Mit146 (53.6 cm, 109 Mb), respectively. Both loci are close to the B-cell hyperactivity, lupus or GN susceptibility loci that have been identified previously. The results of our study suggest that the BXD2 strain of mice is a novel model for complex autoimmune disease that will be useful in identifying the mechanisms critical for the immunopathogenesis and genetic segregation of lupus and erosive arthritis.

Albuminuria↗
PubMed2005

Predicting short-term disease progression among HIV-infected patients in Asia and the Pacific region: preliminary results from the TREAT Asia HIV Observational Database (TAHOD).

OBJECTIVES: HIV disease progression has been well documented in Western populations. This study aimed to estimate the short-term risk of AIDS and death from the TREAT Asia HIV Observational Database (TAHOD), a prospective, multicentre cohort study in Asia and the Pacific region. METHODS: Prospective data were analysed to estimate short-term disease progression. Endpoints were defined as the time from study entry to diagnosis with AIDS or death. Antiretroviral treatment was fitted as a time-dependent variable. Predictors of disease progression were assessed using Cox proportional hazards models, and prognostic models were developed using Weibull models. RESULTS: A total of 1260 patients with prospective follow-up data contributed 477 person-years of follow-up, during which 18 patients died and 34 were diagnosed with AIDS, a combined rate of 10.1 per 100 person-years. Compared with patients receiving antiretroviral treatment, patients not on treatment had a higher rate of disease progression (17.6 vs. 8.1 per 100 person-years, respectively). Baseline CD4 count was the strongest predictor of disease progression. Prognostic models, using either a baseline CD4 count as the sole marker or markers including baseline haemoglobin, AIDS-related symptoms and previous or current antiretroviral treatment, were successful at identifying patients at high risk of short-term disease progression. CONCLUSIONS: Similar to the situation in Western countries, baseline CD4 count was the strongest predictor of short-term disease progression. Prognostic models based on readily available clinical data and haemoglobin level should be useful in estimating short-term clinical risk in HIV-infected patients in Asia and the Pacific region.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Global transcriptome analysis of Shewanella oneidensis MR-1 exposed to different terminal electron acceptors.

To gain insight into the complex structure of the energy-generating networks in the dissimilatory metal reducer Shewanella oneidensis MR-1, global mRNA patterns were examined in cells exposed to a wide range of metal and non-metal electron acceptors. Gene expression patterns were similar irrespective of which metal ion was used as electron acceptor, with 60% of the differentially expressed genes showing similar induction or repression relative to fumarate-respiring conditions. Several groups of genes exhibited elevated expression levels in the presence of metals, including those encoding putative multidrug efflux transporters, detoxification proteins, extracytoplasmic sigma factors and PAS-domain regulators. Only one of the 42 predicted c-type cytochromes in MR-1, SO3300, displayed significantly elevated transcript levels across all metal-reducing conditions. Genes encoding decaheme cytochromes MtrC and MtrA that were previously linked to the reduction of different forms of Fe(III) and Mn(IV), exhibited only slight decreases in relative mRNA abundances under metal-reducing conditions. In contrast, specific transcriptome responses were displayed to individual non-metal electron acceptors resulting in the identification of unique groups of nitrate-, thiosulfate- and TMAO-induced genes including previously uncharacterized multi-cytochrome gene clusters. Collectively, the gene expression results reflect the fundamental differences between metal and non-metal respiratory pathways of S. oneidensis MR-1, where the coordinate induction of detoxification and stress response genes play a key role in adaptation of this organism under metal-reducing conditions. Moreover, the relative paucity and/or the constitutive nature of genes involved in electron transfer to metals is likely due to the low-specificity and the opportunistic nature of the metal-reducing electron transport pathways.

Bacterial Outer Membrane Proteins↗
PubMed2005

The growth hormone receptor gene is associated with mandibular height in a Chinese population.

Genetic influences are important in the determination of mandibular morphology, and growth hormone receptor (GHR) is believed to have an important influence on the growth of craniofacial bone. In this study, we used quantitative trait locus methods to evaluate the relationship between craniofacial morphology and single-nucleotide polymorphisms (SNPs) in GHR in an unselected healthy Chinese population. We systematically screened the 10 exons and nearby introns of GHR and identified 6 SNPs. Using 4 SNPs as markers, we studied the relationships between genotypes and craniofacial linear measurements. Individuals with the genotype CC of polymorphism I526L had a significantly greater mandibular ramus length (condylion-gonion/ articulare-gonion) than those with genotype AC or AA. Haplotype analysis showed that there were also significant differences between the long and short mandibular height groups in an extreme population. Our results indicate that the GHR gene polymorphism I526L is associated with mandibular height in the Chinese population.

Adenine↗
PubMed2005

Hypercatabolism of IgG in mice with lupus-like syndrome.

The metabolism of radioiodinated mouse IgG was studied in mice with lupus-like syndrome before and after the onset of the disease. Before the onset of the disease, the pharmacokinetic parameters of IgG in MLR-1pr and Pristane-primed Balb/c mice were within the normal range of values. After the onset of the disease a considerable increase in the catabolic rate of IgG was recorded abbreviating its half life to less than one third of the normal value. The increased catabolism of IgG could not be related to the concentration--catabolism effect or to the presence of rheumatoid factor and autoantibody or to the IgG loss through the kidney and gastrointestinal tract. The hypercatabolism of IgG was explained by disease-induced impairment of the function of the receptor FcRn, which regulates the homeostasis of IgG.

Animals↗
PubMed2005

Xenobiotic nuclear receptor-mediated regulation of UDP-glucuronosyl-transferases.

UDP-glucuronosyltransferases (UGTs) belong to the Phase II drug metabolizing enzymes. UGTs mediate the transfer of glucuronic acid, from UDP glucuronic acid to predominantly hydrophobic xeno- and endobiotic chemicals, thus facilitating their detoxification and excretion. Deficiency in the expression and/or activity of UGTs may lead to genetic and acquired diseases such as Crigler-Najjar syndrome and jaundice. UGT genes are classified into UGT1A and UGT2B subfamily, and each subfamily and each isoform shows tissue-specific distribution pattern. The underlying mechanisms for this tissue specificity are not fully understood. Emerging evidence have demonstrated that nuclear receptors (NR), such as pregnane X receptor (PXR), constitutive androstane receptor (CAR), peroxisome proliferator-activated receptor (PPAR), can regulate UGTs and this NR-mediated regulation may contribute to the tissue-specific expression pattern of UGTs. The regulations are believed to be both receptor- and UGT isoform-specific. In addition, UGTs are also subject to the regulation by aryl hydrocarbon receptor (AhR) and other tissue-specific transcription factors. Based on their capacity to catalyze the glucuronidation of xenobiotics and endobiotics, UGTs play an important role in hormonal homeostasis, energy metabolism, bilirubin clearance, and xenobiotic detoxification. Therefore, elucidating UGT regulation by nuclear receptors has broader significance in understanding UGT's function in various physiological and patho-physiological conditions.

Animals↗
PubMed2005

A survey of endocrine disrupting chemicals in sewage and a preliminary treatment trial.

This paper demonstrates that synthetic endocrine disrupting chemicals (EDCs) (e.g. bisphenol-A) and natural EDCs (e.g. estrone and 17beta-estradiol) were found in the crude sewage from two sewage treatment works. Conventional biological processes can lower EDC concentrations to several hundred nanograms per litre. Because natural EDCs (e.g. estrone and 17beta1-estradiol) have biological activity and an adverse impact on the environment at extremely low concentrations (several tens of nanograms per litre), and because the existing wastewater/sewage treatment processes are not adequate to reduce natural EDC concentrations lower than 100 ng L(-1), further treatment after conventional biological processes is required. Preliminary trials with ferrate (VI) and electrochemical oxidation processes demonstrated that the former is more effective than the latter in reducing EDC concentrations, and that both the processes can effectively reduce EDCs to very low levels, ranging between 20 and 100 ng L(-1).

Benzhydryl Compounds↗
PubMed2004

Dimethyl methylphosphonate decomposition on Cu surfaces: supported Cu nanoclusters and films on TiO2(110).

The thermal decomposition of dimethyl methylphosphonate (DMMP), which is a simulant molecule for organophosphorus nerve agents, has been investigated on Cu clusters as well as on Cu films deposited on a TiO(2)(110) surface. Scanning tunneling microscopy studies were conducted to characterize the cluster sizes and surface morphologies of the deposited Cu clusters and films. Temperature-programmed desorption experiments demonstrated that the surface chemistry of DMMP is not sensitive to the size of the Cu clusters over the range studied in this work. DMMP reaction on an annealed 40 monolayer Cu film resulted in the desorption of H(2), methane, methyl, formaldehyde, methanol, and molecular DMMP, and reaction on the small (4.4 +/- 0.9 nm diameter, 1.8 +/- 0.6 nm height) and large (10.7 +/- 1.9 nm diameter, 4.8 +/- 1.0 nm height) Cu clusters generated similar products. Formaldehyde and methane production is believed to occur via a methoxy intermediate on the Cu surface. These products are favored on the higher coverage Cu films that completely cover the TiO(2) surface since competing reaction pathways on TiO(2) are suppressed. X-ray photoelectron spectroscopy studies showed that DMMP begins to decompose on the Cu clusters upon adsorption at room temperature and that atomic carbon, atomic phosphorus, and PO(x) remain on the surface after DMMP decomposition.

Journal Article↗
PubMed2004

Estradiol alters transcription factor gene expression in primate prefrontal cortex.

Estrogen protects neurons from a variety of experimental insults in vitro, and is thought to protect from acute and chronic neurodegenerative processes in vivo. Estrogen also enhances higher-level cognitive functions that are centered in the dorsolateral prefrontal cortex (DLPFC) in human and non-human primates. To investigate genomic mechanisms involved in estrogenic effects on the primate brain in vivo, we compared transcription factor mRNA and protein expression in the DLPFC of ovariectomized rhesus monkeys treated with either vehicle or estradiol (E2). c-FOS, E2F1, and general transcription factor IIB (TFIIB) mRNA and protein expression were altered significantly by short-term E2 treatment, as shown by DNA array, in situ hybridization, and immunohistochemical and immunoblot evaluations. C-FOS expression was increased significantly whereas E2F1 and TFIIB levels were decreased in the DLPFC of E2-treated animals. These transcription factors were concentrated in cortical pyramids, as were estrogen receptors alpha and beta. These data indicate that estrogen may have direct as well as indirect effects on neuronal gene expression in the primate prefrontal cortex.

Animals↗