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Wei Hu

Publications and source records attributed to Wei Hu.

At least 37 records · Page 2Linked to original sources
PubMed2006

New perspectives on host-parasite interplay by comparative transcriptomic and proteomic analyses of Schistosoma japonicum.

Schistosomiasis remains a serious public health problem with an estimated 200 million people infected in 76 countries. Here we isolated ~ 8,400 potential protein-encoding cDNA contigs from Schistosoma japonicum after sequencing circa 84,000 expressed sequence tags. In tandem, we undertook a high-throughput proteomics approach to characterize the protein expression profiles of a number of developmental stages (cercariae, hepatic schistosomula, female and male adults, eggs, and miracidia) and tissues at the host-parasite interface (eggshell and tegument) by interrogating the protein database deduced from the contigs. Comparative analysis of these transcriptomic and proteomic data, the latter including 3,260 proteins with putative identities, revealed differential expression of genes among the various developmental stages and sexes of S. japonicum and localization of putative secretory and membrane antigens, enzymes, and other gene products on the adult tegument and eggshell, many of which displayed genetic polymorphisms. Numerous S. japonicum genes exhibited high levels of identity with those of their mammalian hosts, whereas many others appeared to be conserved only across the genus Schistosoma or Phylum Platyhelminthes. These findings are expected to provide new insights into the pathophysiology of schistosomiasis and for the development of improved interventions for disease control and will facilitate a more fundamental understanding of schistosome biology, evolution, and the host-parasite interplay.

Amino Acid Sequence↗
PubMed2006

Serum amyloid A generates high density lipoprotein with cellular lipid in an ABCA1- or ABCA7-dependent manner.

Serum amyloid A (SAA) is an amphiphilic helical protein that is found associated with plasma HDL in various pathological conditions, such as acute or chronic inflammation. Cellular lipid release and generation of HDL by this protein were investigated, in comparison with the reactions by apolipoprotein A-I (apoA-I) and several types of cells that appear with various specific profiles of cholesterol and phospholipid release. SAA mediated cellular lipid release from these cells with the same profile as apoA-I. Upregulation of cellular ABCA1 protein by liver X receptor/retinoid X receptor agonists resulted in an increase of cellular lipid release by apoA-I and SAA. SAA reacted with the HEK293-derived clones that stably express human ABCA1 (293/2c) or ABCA7 (293/6c) to generate cholesterol-containing HDL in a similar manner to apoA-I. Dibutyryl cyclic AMP and phorbol 12-myristate 13-acetate, which differentiate apoA-I-mediated cellular lipid release between 293/2c and 293/6c, also exhibited the same differential effects on the SAA-mediated reactions. No evidence was found for the ABCA1/ABCA7-independent lipid release by SAA. Characterization of physicochemical properties of the HDL revealed that SAA-generated HDL particles had higher density, larger diameter, and slower electrophoretic mobility than those generated by apoA-I. These results demonstrate that SAA generates cholesterol-containing HDL directly with cellular lipid and that the reaction is mediated by ABCA1 and ABCA7.

ATP Binding Cassette Transporter 1↗
PubMed2006

Integration of double-fluorescence expression vectors into zebrafish genome for the selection of site-directed knockout/knockin.

Production of zebrafish by modifying endogenous growth hormone (GH) gene through homologous recombination is described here. We first constructed the targeting vectors pGHT1.7k and pGHT2.8k, which were used for the knockout/knockin of the endogenous GH gene of zebrafish, and injected these two vectors into the embryos of zebrafish. Overall, the rate of targeted integration with the characteristic of germ line transmission in zebrafish was 1.7 x 10(-6). In one experimental patch, the integrating efficiency of pGHT2.8k was higher than that of pGHT1.7k, but the lethal effect of pGHT2.8k was stronger than that of pGHT1.7k. The clones with the correct integration of target genes were identified by a simple screening procedure based on green fluorescent protein (GFP) and RFP dual selection, which corresponded to homologous recombination and random insertion, respectively. The potential homologous recombination zebrafish was further bred to produce a heterozygous F1 generation, selected based on the presence of GFP. The potential targeted integration of exogenous GH genes into a zebrafish genome at the P0 generation was further verified by polymerase chain reaction and Southern blot analysis. Approximately 2.5% of potential founder knockout and knockin zebrafish had the characteristic of germ line transmission. In this study, we developed an efficient method for producing the targeted gene modification in zebrafish for future studies on genetic modifications and gene functions using this model organism.

Animals↗
PubMed2006

Expression of CLC-K chloride channels in the rat cochlea.

Current models of the lateral K+ recycling pathway in the mammalian cochlea include two multicellular transport networks separated from one another by three interstitial gaps. The first gap is between outer hair cells and Deiters cells, the second is between outer sulcus cells and type II spiral ligament fibrocytes and the third is between intermediate and marginal cells in the stria vascularis. K+ taken up by cells bordering these interstitial spaces is accompanied by Cl-. Maintaining appropriate electrolyte balance and membrane potentials in these cells requires a mechanism for exit of the resorbed Cl-. One possible candidate for regulating this Cl- efflux is ClC-K, a chloride channel previously thought to be kidney specific. Here, we demonstrate the expression of both known isoforms of ClC-K in the organ of Corti, spiral ligament and stria vascularis of the rat cochlea by immunohistochemical, Western blot and RT-PCR analysis. These results indicate a role for ClC-K in mediating Cl- recycling in the cochlea. The widespread expression of both ClC-K isoforms in the cochlea may help to explain the symptoms of Bartter's syndrome Type III, a mutation in the hClC-Kb gene (human homologue of ClC-K2), which results in renal salt wasting without deafness. These data support the hypothesis that both isoforms of ClC-K are co-expressed in some cell membranes and account for the preservation of hearing in the presence of a mutation in only one channel isoform.

Animals↗
PubMed2006

Interleukin 23 in acute inflammatory demyelination of the peripheral nerve.

BACKGROUND: Interleukin (IL) 23, a newly identified heterodimeric proinflammatory cytokine and a novel IL-12 family member comprising the p40 subunit of IL-12 but a different p19 subunit, has been reported to preferentially act on memory T cells and play an important role during cellular immune responses. Recent evidence suggests that IL-23 rather than IL-12 is critically involved in the pathogenesis of various immune-mediated disorders. OBJECTIVE: To determine the role of IL-23p19 during the course of acute immune-mediated demyelinating diseases of the peripheral nervous system. DESIGN: The sequential RNA expression of IL-23p19 in sciatic nerves from rats with experimental autoimmune neuritis, an animal model of the human Guillain-Barré syndrome (GBS), was analyzed by semiquantitative reverse transcriptase-polymerase chain reaction. Expression and distribution patterns of IL-23p19 protein were studied in sural nerve biopsies and cerebrospinal fluid samples from 5 patients with classical Guillain-Barré syndrome and 5 controls with noninflammatory neuropathies using immunohistochemistry and immunoblotting, respectively. RESULTS: We found IL-23p19 RNA to be up-regulated prior to the onset of first clinical symptoms with peak expression levels preceding maximum disease severity during experimental autoimmune neuritis. In patients, IL-23p19 protein was detectable in cerebrospinal fluid samples from patients with Guillain-Barré syndrome, and endoneurial macrophages were identified as the cellular source of IL-23p19 in sural nerve biopsies. CONCLUSION: Our present data indicate that IL-23 may play an important role during the early effector phase in immune-mediated demyelination of the peripheral nerve.

Animals↗
PubMed2006

Golgi alkaline ceramidase regulates cell proliferation and survival by controlling levels of sphingosine and S1P.

Sphingosine-1-phosphate (S1P), a sphingolipid metabolite, promotes cell proliferation and survival whereas its precursor, sphingosine, has the opposite effects. However, much remains unknown about their regulation. Here we identify a novel human ceramidase (haCER2) that regulates the levels of both sphingosine and S1P by controlling the hydrolysis of ceramides. haCER2 is localized to the Golgi complex and is highly expressed in the placenta. High ectopic expression of haCER2 caused fragmentation of the Golgi complex and growth arrest in HeLa cells due to sphingosine accumulation. Low ectopic expression of haCER2 increased S1P without sphingosine accumulation, promoting cell proliferation in serum-free medium. This proliferative effect was suppressed by dimethylsphingosine, an inhibitor of the S1P formation, or by the RNA interference (RNAi) -mediated inhibition of S1P(1,) a G-protein-coupled receptor for S1P. The RNAi-mediated down-regulation of haCER2 enhanced the serum deprivation-induced growth arrest and apoptosis of HeLa cells, which was inhibited by addition of exogenous S1P. Serum deprivation up-regulated both haCER2 mRNA and activity in HeLa cells. haCER2 mRNA is also up-regulated in some tumors. Taken together, these results suggest that haCER2 is important for the generation of S1P and S1P-mediated cell proliferation and survival, but that its overexpression may cause cell growth arrest due to an accumulation of sphingosine.

Alkaline Ceramidase↗
PubMed2006

Syphilis among female sex workers in southwestern China: potential for HIV transmission.

OBJECTIVE: The objective of this study was to investigate the prevalence and risk factors of syphilis infection among female sex workers in a southwestern Chinese city along a drug trafficking route. METHODS: From December 2004 to January 2005, 343 female sex workers (FSWs) were recruited through community outreach and peer referring. Confidential questionnaire interviews were administered to collect information on sexual and other sexually transmitted diseases/HIV risk behaviors. Cervical and blood samples were collected to test for syphilis and HIV antibodies and Neisseria gonorrhoeae infection; Condyloma acuminatum infection was diagnosed clinically. RESULTS: Of 343 FSWs, 15.7% were infected with syphilis. The prevalence of HIV, gonorrhea, and C. acuminatum was 0.6%, 2.0%, and 1.5%, respectively. The subtype of 2 HIV-1 infections was both CRF 07BC. Nearly 10% of FSWs reported using illicit drugs. Consistent use, inconsistent use, and never use of condoms with commercial sex clients in the last month were reported by 53.9%, 38.5%, and 7.6% FSWs, respectively. Longer duration of sex work (odds ratio [OR] = 1.98; 95% confidence interval [CI] = 1.08-3.62), working at low-end establishments (OR = 2.03; 95% CI = 1.10-3.76), and if primary sex partners had sex with other women in the past 6 months (OR = 2.06; 95% CI = 1.08-3.91) were independently associated with syphilis infection. CONCLUSIONS: High prevalence of syphilis and overlapped unprotected commercial sex and drug using behaviors among FSWs along a drug-trafficking route may suggest a potential for rapid spread of HIV from injection drug users to FSWs and then to the general population and underscore the urgency of preventive interventions to break the bridge of FSWs for HIV/sexually transmitted disease spread.

Adolescent↗
PubMed2006

Characterization of a novel putative zinc finger gene MIF1: involvement in multiple hormonal regulation of Arabidopsis development.

Phytohormones play crucial roles in regulating many aspects of plant development. Although much has been learned about the effects of individual hormones, cross-talk between and integration of different hormonal signals are still not well understood. We present a study of MINI ZINC FINGER 1 (MIF1), a putative zinc finger protein from Arabidopsis, and suggest that it may be involved in integrating signals from multiple hormones. MIF1 homologs are highly conserved among seed plants, each characterized by a very short sequence containing a central putative zinc finger domain. Constitutive overexpression of MIF1 caused dramatic developmental defects, including dwarfism, reduced apical dominance, extreme longevity, dark-green leaves, altered flower morphology, poor fertility, reduced hypocotyl length, spoon-like cotyledons, reduced root growth, and ectopic root hairs on hypocotyls and cotyledons. In addition, 35S::MIF1 seedlings underwent constitutive photomorphogenesis in the dark, with root growth similar to that in the light. Furthermore, 35S::MIF1 seedlings were demonstrated to be non-responsive to gibberellin (GA) for cell elongation, hypersensitive to the GA synthesis inhibitor paclobutrazol (PAC) and abscisic acid (ABA), and hyposensitive to auxin, brassinosteroid and cytokinin, but normally responsive to ethylene. The de-etiolation defect could not be rescued by the hormones tested. Consistent with these observations, genome-scale expression profiling revealed that 35S::MIF1 seedlings exhibited decreased expression of genes involved in GA, auxin and brassinosteroid signaling as well as cell elongation/expansion, and increased expression of ABA-responsive genes. We propose that MIF1, or the protein(s) with which MIF1 interacts, is involved in mediating the control of plant development by multiple hormones.

Abscisic Acid↗
PubMed2006

Targeting Aurora kinases in ovarian cancer.

Although recurrent epithelial ovarian cancer initially responds well to current first-line adjuvant therapy, eventually the disease becomes resistant to chemotherapy. Novel strategies are needed to reverse chemoresistance in order to treat relapsed ovarian cancer effectively. One strategy is to target aberrant expression activation of Aurora kinases that are essential for the regulation of chromosome segregation and cytokinesis during mitosis and which play a role in tumourigenesis and progression in a wide range of human tumours, including ovarian cancer. The purpose of this article is to review Aurora kinases and their inhibitors in human epithelial ovarian cancer as an impetus to the development of effective and less toxic regimens for ovarian cancer. In addition, this review tries to define the differences between cytotoxic chemotherapeutic agents and molecular therapeutic agents: both groups of agents have either a single specific target or multiple specific targets, while their differences lie in their toxicity profiles and the way to determine their dosages for further studies. The authors propose that Aurora kinase inhibitors be developed as molecular therapeutic agents in order to minimise their toxicities and maximise their antitumour activities for ovarian cancer treatment.

Animals↗
PubMed2006

Targeted therapies in gynecologic cancers.

With the rapid development of high-throughput techniques for identifying novel specific molecular targets in human cancer over the past few years, attention to targeted cancer therapy has dramatically increased. The term "targeted cancer therapy" refers to a new generation of drugs designed to interfere with a specific molecular target that is believed to play a critical role in tumor growth or progression, is not expressed significantly in normal cells, and is correlated with clinical outcome. There has been a rapid increase in the identification of targets that have potential therapeutic application. The clinical success of the small-molecule kinase inhibitor imatinib mesylate in chronic myeloid leukemia and gastrointestinal stromal tumors has accelerated the development of a new era of molecular targeted cancer therapy. The number of agents under preclinical and clinical investigation has grown accordingly. This emphasis on molecular biology and genetics has also resulted in significant changes in the treatment of gynecologic cancers. Several promising drugs targeting tyrosine kinases (EGFR and Her-2/Neu), mTOR, Raf kinase, proteasome, and histone deacetylases, as well as drugs affecting apoptosis and mitosis, are under development for clinical application. However, some clinical trials of p53 gene therapies and farnesyl transferase inhibitors have had limited success. In this review, we will focus on potential novel targets in gynecologic cancer and the development of targeted therapy and its clinical applications in gynecologic cancer.

Angiogenesis Inhibitors↗
PubMed2006

[Preparation of recombinant IL-1 fusion protein as the substrate for HCV NS3 serine protease].

AIM: To prepare recombinant IL-1 fusion protein as the substrate for the HCV NS3 serine protease. METHODS: NS5A-B gene fragment (2,412-2,427aa) synthesized by PCR was subcloned into prokaryotic expression vector pBVIL1 to fuse with IL-1 gene and the recombinant vector pBVIL1/NS5A-B was transformed into E.coli strain HB101. The fused protein was induced to express at 42degreesCelsius and purified by two-step column chromatography. The proteolysis of the purified IL-1 fusion protein catalyzed by NS3 serine protease was analyzed with SDS-PAGE, Western blot and ELISA. RESULTS: NS5A-B fragment gene was correctly subcloned into pBVIL1 vector and the fusion protein was expressed as inclusion body in transformed HB101 cells. The recombinant fusion protein can be cleaved into smaller fragments by NS3 protease. CONCLUSION: The recombinant fusion protein can be cleaved by NS3 serine protease successfully and specifically, suggesting that it can be used as a surrogate substrate of NS3 serine protease in searching for inhibitors of this protease.

Amino Acid Sequence↗
PubMed2006

Preliminary study of mesenchymal stem cells-seeded type I collagen-glycosaminoglycan matrices for cartilage repair.

OBJECTIVE: To investigate the possibility of repairing articular cartilage defects with the mesenchymal stem cells (MSCs)- seeded type I collagen-glycosaminoglycan(CG) matrices after being cultured with the chondrogenic differentiation medium. METHODS: The adherent population of MSCs from bone marrow of 10 adult dogs were expanded in number to the 3rd passage. MSCs were seeded into the dehydrothermal treatment (DHT) cross-linked CG matrices; 2 x 10(6) cells per 9-mm diameter samples were taken. Chondrogenic differentiation was achieved by the induction media for 3 weeks. Cell contractility was evaluated by the measurement of the cell-mediated contraction of the CG matrices with time in culture. The in vitro formation of the cartilage was assessed by an assay employing immunohistochemical identification of type II collagen and by immunohistochemistry to demonstrate smooth muscle actin (SMA). The cells seedling CGs were implanted into cartilage defects of canine knee joints. Twelve weeks after surgery, the dogs were sacrificed and results were observed. RESULTS: There was significant contraction of the MSCs-seeded DHT cross-linked CG scaffolds cultured in the cartilage induction medium. After 21 days, the MSC-seeded DHT cross-linked matrices were contracted to 64.4% +/- 0.3%; histologically, the pores were found to be compressed and the contraction coupled with the newly synthesized matrix, transforming the MSCs-seeded CG matrix into a solid tissue in most areas. The type II collagen staining was positive. The SMA staining was positive when these MSCs were seeded and the contracted CGs were implanted into the cartilage defects of the canine knee joints to repair the cartilage defects. The function of the knee joints recovered and the solid cartilaginous tissue filled the cartilage defects. Conclusion The results demonstrates that MSCs grown in the CG matrices can produce a solid cartilaginous tissue containing type II collagen after being cultured with the chondrogenic differentiation medium and implanted into cartilage defects. We hypothesize that the following steps can be performed in the chondrogenic process: (1)MSCs express SMA, resulting in matrix contraction, thus achieving a required cell density (allowing the cells to operate in a necessary society); (2)Cells interact to form a type II collagen-containing extracellular matrix (and cartilaginous tissue); (3)Other factors, such as an applied mechanical stress, may be required to form a mature cartilage with the normal architecture.

Animals↗
PubMed2006

[Resolution of racemic anti-hepatitis drug ( +/- ) -bicyclol].

AIM: To study the different biological activities of the enantiomers of the anti-hepatitis drug (+/-)-bicyclol, the (+/-)-bicyclol was resolved. METHODS: By being treated with optically active alkaloid, the two diastereoisomers alkaloid salts of the compound could be obtained, separately. After decomposing and methylating, they were transformed separately into (-)-bicyclol and (+)-bicyclol. RESULTS: The two enantiomers of bicyclol were determined by melting point, [alpha]D, 1H NMR, MS and chiral column HPLC. CONCLUSION: Comparison of hepatoprotective action of racemic bicyclol and (-)-, (+)-bicyclol on experimental liver injury, the effect of (-)-bicyclol was two times more potent than that of racemic bicyclol and the potency of (+)-bicyclol was much less than that of the racemate.

Alanine Transaminase↗
PubMed2006

[Cloning of A73 gene and its coding sequence analysis].

OBJECTIVE: To clone A73 gene of Epstein-Barr virus (EBV) and examine the variation of its coding sequence. METHODS: A73 coding sequence (CDS) amplified from 7 patients in nasophryngeal carcinoma (NPC) biopsies by RT-PCR was cloned into pGEM-T-Easy vector to construct the recombinant plasmid, which was subjected to sequence analysis in Gen Bank database using Blast software. RESULTS: A73 gene from nasophryngeal carcinoma was successfully cloned into pGEM-T Easy vector. A locus with conversion of A-->C in A73 was found at CDS 45 nt, located in the exonVB157154 nt, which did not result in an amino acid replacement, and the variation frequency was 7/7. CONCLUSION: There is a point mutation in A73 CDS of EBV isolated from NPC tissue, which might produce NPC-associated polymorphism with possible involvement in the composition of some subtype of EB virus.

Cloning, Molecular↗
PubMed2006

[Reversion of multidrug resistance (MDR) in human glioma cells by RNA interference (RNAi)].

OBJECTIVE: To explore whether the constructed vector of short haprin in vivo can induce human glioma cell line BT325 to produce RNAi duplexes and reverse the expression of MDR1 gene. METHODS: Three 62nt oligonucleotide fragments (shRNA) were constructed according to GenBank MDR1 sequence and were cloned to the retrovirus-delivered vectors. After transfected these vectors directly into the human malignant glioma BT325 cells by lipofectamine 2000 with enhanced green fluorescence protein (EGFP) co-transfecting, the MDR1 gene silence effects were detected by the changing level of mRNA and P-glycoprotein including real time PCR (RT-PCR), Northern blot and Western blot analysis. To assess the multidrug resistance against adriamycin (ADR) and VCR, cell proliferation assays were performed by cell counting kit-8. RESULTS: The RNAi plasmid vectors were constructed successfully. RT-PCR showed MDR1 mRNA was significantly reduced (P < 0.05). Northern blot analysis showed that the gene silence became most intense at 48 hours after transfection. Western blot analysis demonstrated that P-gp expression was reduced at different time to 12.9%, 30.3% and 4.8%, respectively. The chemosensitivity assays indicated that the transfected cells showed an enhanced sensitivity to ADR and VCR. Based on the value of IC(50), BT325 cells had significantly increased sensitivity to the drugs. CONCLUSION: The sequence specific RNAi can inhibit MDR1 mRNA and P-gp expression in the glioma cell line. It may reverse multidrug resistance phenotype, therefore, may provide promising therapeutic modalities in the treatment of human glioma.

ATP Binding Cassette Transporter, Subfamily B, Mem↗