February 2017

Monthly Archive

Expression of hepatitis B virus surface antigens induces defective gonad phenotypes in Caenorhabditis elegans.

Posted by on 28 Feb 2017 | Tagged as: Hepatitis B Alternative Medicine

Related Articles Expression of hepatitis B virus surface antigens induces defective gonad phenotypes in Caenorhabditis elegans. World J Virol. 2017 Feb 12;6(1):17-25 Authors: Chen YY, Lee LW, Hong WN, Lo SJ Abstract AIM: To test whether a simple animal, Caenorhabditis elegans (C. elegans), can be used as an alternative model to study the interaction between hepatitis B virus antigens (HBsAg) and host factors. METHODS: Three plasmids that were able to express the large, middle and small forms of HBsAgs (LHBsAg, MHBsAg, and SHBsAg, respectively) driven by a ubiquitous promoter (fib-1) and three that were able to express SHBsAg driven by different tissue-specific promoters were constructed and microinjected into worms. The brood size, egg-laying rate, and gonad development of transgenic worms were analyzed using microscopy. Levels of mRNA related to endoplasmic reticulum stress, enpl-1, hsp-4, pdi-3 and xbp-1, were determined using reverse transcription polymerase reaction (RT-PCRs) in three lines of transgenic worms and dithiothreitol (DTT)-treated wild-type worms. RESULTS: Severe defects in egg-laying, decreases in brood size, and gonad retardation were observed in transgenic worms expressing SHBsAg whereas moderate defects were observed in transgenic worms expressing LHBsAg and MHBsAg. RT-PCR analysis revealed that enpl-1, hsp-4 and pdi-3 transcripts were significantly elevated in worms expressing LHBsAg and MHBsAg and in wild-type worms pretreated with DTT. By contrast, only pdi-3 was increased in worms expressing SHBsAg. To further determine which tissue expressing SHBsAg could induce gonad retardation, we substituted the fib-1 promoter with three tissue-specific promoters (myo-2 for the pharynx, est-1 for the intestines and mec-7 for the neurons) and generated corresponding transgenic animals. Moderate defective phenotypes were observed in worms expressing SHBsAg in the pharynx and intestines but not in worms expressing SHBsAg in the neurons, suggesting that the secreted SHBsAg may trigger a cross-talk signal between the digestive track and the gonad resulting in defective phenotypes. CONCLUSION: Ectopic expression of three forms of HBsAg that causes recognizable phenotypes in transgenic worms suggests that C. elegans can be used as an alternative model for studying virus-host interactions because the resulting phenotype is easily detected through microscopy. PMID: 28239568 [PubMed – in process]

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Expression of hepatitis B virus surface antigens induces defective gonad phenotypes in Caenorhabditis elegans.

B-cell repertoire dynamics after sequential hepatitis B vaccination and evidence for cross-reactive B-cell activation.

Posted by on 26 Feb 2017 | Tagged as: Hepatitis B Alternative Medicine

Related Articles B-cell repertoire dynamics after sequential hepatitis B vaccination and evidence for cross-reactive B-cell activation. Genome Med. 2016 06 16;8(1):68 Authors: Galson JD, Trück J, Clutterbuck EA, Fowler A, Cerundolo V, Pollard AJ, Lunter G, Kelly DF Abstract BACKGROUND: A diverse B-cell repertoire is essential for recognition and response to infectious and vaccine antigens. High-throughput sequencing of B-cell receptor (BCR) genes can now be used to study the B-cell repertoire at great depth and may shed more light on B-cell responses than conventional immunological methods. Here, we use high-throughput BCR sequencing to provide novel insight into B-cell dynamics following a primary course of hepatitis B vaccination. METHODS: Nine vaccine-naïve participants were administered three doses of hepatitis B vaccine (months 0, 1, and 2 or 7). High-throughput Illumina sequencing of the total BCR repertoire was combined with targeted sequencing of sorted vaccine antigen-enriched B cells to analyze the longitudinal response of both the total and vaccine-specific repertoire after each vaccine. ELISpot was used to determine vaccine-specific cell numbers following each vaccine. RESULTS: Deconvoluting the vaccine-specific from total BCR repertoire showed that vaccine-specific sequence clusters comprised <0.1 % of total sequence clusters, and had certain stereotypic features. The vaccine-specific BCR sequence clusters were expanded after each of the three vaccine doses, despite no vaccine-specific B cells being detected by ELISpot after the first vaccine dose. These vaccine-specific BCR clusters detected after the first vaccine dose had distinct properties compared to those detected after subsequent doses; they were more mutated, present at low frequency even prior to vaccination, and appeared to be derived from more mature B cells. CONCLUSIONS: These results demonstrate the high-sensitivity of our vaccine-specific BCR analysis approach and suggest an alternative view of the B-cell response to novel antigens. In the response to the first vaccine dose, many vaccine-specific BCR clusters appeared to largely derive from previously activated cross-reactive B cells that have low affinity for the vaccine antigen, and subsequent doses were required to yield higher affinity B cells. PMID: 27312086 [PubMed – indexed for MEDLINE]

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B-cell repertoire dynamics after sequential hepatitis B vaccination and evidence for cross-reactive B-cell activation.

An end-point method based on graphene oxide for RNase H analysis and inhibitors screening.

Posted by on 24 Feb 2017 | Tagged as: Hepatitis B Alternative Medicine

Related Articles An end-point method based on graphene oxide for RNase H analysis and inhibitors screening. Biosens Bioelectron. 2017 Apr 15;90:103-109 Authors: Zhao C, Fan J, Peng L, Zhao L, Tong C, Wang W, Liu B Abstract As a highly conserved damage repair protein, RNase H can hydrolysis DNA-RNA heteroduplex endonucleolytically and cleave RNA-DNA junctions as well. In this study, we have developed an accurate and sensitive RNase H assay based on fluorophore-labeled chimeric substrate hydrolysis and the differential affinity of graphene oxide on RNA strand with different length. This end-point measurement method can detect RNase H in a range of 0.01 to 1 units /mL with a detection limit of 5.0×10(-3) units/ mL under optimal conditions. We demonstrate the utility of the assay by screening antibiotics, resulting in the identification of gentamycin, streptomycin and kanamycin as inhibitors with IC50 of 60±5µM, 70±8µM and 300±20µM, respectively. Furthermore, the assay was reliably used to detect RNase H in complicated biosamples and found that RNase H activity in tumor cells was inhibited by gentamycin and streptomycin sulfate in a concentration-dependent manner. The average level of RNase H in serums of HBV infection group was similar to that of control group. In summary, the assay provides an alternative tool for biochemical analysis for this enzyme and indicates the feasibility of high throughput screening inhibitors of RNase H in vitro and in vivo. PMID: 27886596 [PubMed – indexed for MEDLINE]

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An end-point method based on graphene oxide for RNase H analysis and inhibitors screening.

Multicenter study of skin rashes and hepatotoxicity in antiretroviral-naïve HIV-positive patients receiving non-nucleoside reverse-transcriptase…

Posted by on 22 Feb 2017 | Tagged as: Hepatitis B Alternative Medicine

Related Articles Multicenter study of skin rashes and hepatotoxicity in antiretroviral-naïve HIV-positive patients receiving non-nucleoside reverse-transcriptase inhibitor plus nucleoside reverse-transcriptase inhibitors in Taiwan. PLoS One. 2017;12(2):e0171596 Authors: Wu PY, Cheng CY, Liu CE, Lee YC, Yang CJ, Tsai MS, Cheng SH, Lin SP, Lin DY, Wang NC, Lee YC, Sun HY, Tang HJ, Hung CC Abstract OBJECTIVES: Two nucleos(t)ide reverse-transcriptase inhibitors (NRTIs) plus 1 non-NRTI (nNRTI) remain the preferred or alternative combination antiretroviral therapy (cART) for antiretroviral-naive HIV-positive patients in Taiwan. The three most commonly used nNRTIs are nevirapine (NVP), efavirenz (EFV) and rilpivirine (RPV). This study aimed to determine the incidences of hepatotoxicity and skin rashes within 4 weeks of initiation of cART containing 1 nNRTI plus 2 NRTIs. METHODS: Between June, 2012 and November, 2015, all antiretroviral-naive HIV-positive adult patients initiating nNRTI-containing cART at 8 designated hospitals for HIV care were included in this retrospective observational study. According to the national HIV treatment guidelines, patients were assessed at baseline, 2 and 4 weeks of cART initiation, and subsequently every 8 to 12 weeks. Plasma HIV RNA load, CD4 cell count and aminotransferases were determined. The toxicity grading scale of the Division of AIDS (DAIDS) 2014 was used for reporting clinical and laboratory adverse events. RESULTS: During the 3.5-year study period, 2,341 patients initiated nNRTI-containing cART: NVP in 629 patients, EFV 1,363 patients, and RPV 349 patients. Rash of any grade occurred in 14.1% (n = 331) of the patients. In multiple logistic regression analysis, baseline CD4 cell counts (per 100-cell/μl increase, adjusted odds ratio [AOR], 1.125; 95% confidence interval [95% CI], 1.031-1.228) and use of NVP (AOR, 2.443; 95% CI, 1.816-3.286) (compared with efavirenz) were independently associated with the development of skin rashes. Among the 1,455 patients (62.2%) with aminotransferase data both at baseline and week 4, 72 (4.9%) developed grade 2 or greater hepatotoxicity. In multiple logistic regression analysis, presence of antibody for hepatitis C virus (HCV) (AOR, 2.865; 95% CI, 1.439-5.704) or hepatitis B surface antigen (AOR, 2.397; 95% CI, 1.150-4.997), and development of skin rashes (AOR, 2.811; 95% CI, 1.051-7.521) were independently associated with the development of hepatotoxicity. CONCLUSIONS: The baseline CD4 cell counts and use of NVP were associated with increased risk of skin rashes, while hepatotoxicity was independently associated with HCV or hepatitis B virus coinfection, and development of skin rashes in antiretroviral-naïve HIV-positive Taiwanese patients within 4 weeks of initiation of nNRTI-containing regimens. PMID: 28222098 [PubMed – in process]

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Multicenter study of skin rashes and hepatotoxicity in antiretroviral-naïve HIV-positive patients receiving non-nucleoside reverse-transcriptase…