Biomedical subjects

Shu-Mei Lin

Publications and source records attributed to Shu-Mei Lin.

12 recordsLinked to original sources

PubMed2006

Host susceptibility to persistent hepatitis B virus infection.

Genetic epidemiology researches such as twin studies, family-clustering of hepatitis B virus (HBV) infection studies and ethnic difference studies have provided the evidence that host genetic factors play an important role in determining the outcome of HBV infection. The opening questions include which human genes are important in infection and how to find them. Though a number of studies have sought genetic associations between HBV infection/persistence and gene polymorphisms, the candidate gene-based approach is clearly inadequate to fully explain the genetic basis of the disease. With the advent of new genetic markers and automated genotyping, genetic mapping can be conducted extremely rapid. This approach has been successful in some infectious diseases. Linkage analysis can find host genes susceptible to HBV and is of great clinical importance.

Genetic Linkage↗

PubMed2006

Protoplast fusion between Geotrichum candidium and Phanerochaete chrysosporium to produce fusants for corn stover fermentation.

Lignin impedes the digestion of corn stover when used as an animal feed. Phanerochaete chrysosporium is an efficient lignindegrader. Geotrichum candidum can be used to produce single-cell protein. In this study, protoplasts of the two fungi were prepared and fused. After screening, one of the fusants, Fusant R1, was selected for corn stover fermentation. It decreased lignin from 109 to 54 g/kg and increased protein from 48 to 67 g/kg in corn stover. Comparison with their parental strains indicated that the fusant obtained the lignin-degrading ability from P. chrysosporium and the protein-accumulating ability from G. candidium.

Biomass↗

PubMed2006

Screening and identification of interacting proteins with hepatitis B virus core protein in leukocytes and cloning of new gene C1.

AIM: To investigate the biological function of HBcAg in pathogenesis of HBV replication in peripheral blood mononuclear cells (PBMCs). METHODS: HBcAg region was amplified by polymerase chain reaction (PCR) and HBV HBcAg bait plasmid pGBKT7-HBcAg was constructed by routine molecular biological methods. Then the recombinant plasmid DNA was transformed into yeast AH109. After the HBV core protein was expressed in AH109 yeast strains (Western blot analysis), yeast-two hybrid screening was performed by mating AH109 with Y187 containing leukocyte cDNA library plasmid. Diploid yeast cells were plated on synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) (QDO) and synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) (TDO). The second screening was performed with the LacZ report gene ( yeast cells were grown in QDO medium containing X-alpha-gal). The interaction between HBV core protein and the protein obtained from positive colonies was further confirmed by repeating yeast-two hybrid. After plasmid DNA was extracted from blue colonies and sequenced, the results were analyzed by bioinformatic methods. RESULTS: Eighteen colonies were obtained and sequenced, including hypermethylated in cancer 2 (3 colones), eukaryotic translation elongation factor 2 (2 colones), acetyl-coenzyme A synthetase 3 (1 colone), DNA polymerase gamma (1 colone), putative translation initiation factor (1 colone), chemokine (C-C motif) receptor 5 (1 colone), mitochondrial ribosomal protein L41 (1 colone), kyot binding protein genes (1 colone), RanBPM (1 colone), HBeAg-binding protein 3 (1 colone), programmed cell death 2 (1 colone). Four new genes with unknown function were identified. CONCLUSION: Successful cloning of genes of HBV core protein interacting proteins in leukocytes may provide some new clues for studying the biological functions of HBV core protein.

Amino Acid Sequence↗

PubMed2006

Tumor necrosis factor receptor deficiency exacerbated Adriamycin-induced cardiomyocytes apoptosis: an insight into the Fas connection.

Cardiomyopathy is a major dose-limiting factor for applications of Adriamycin, a potent chemotherapeutic agent. The present study tested the hypothesis that increased tumor necrosis factor (TNF)-alpha signaling via its receptors protects against Adriamycin-induced cardiac injury. We used mice in which both TNF receptor I and II have been selectively inactivated (DKO) with wild-type mice as controls. Morphometric studies of cardiac tissue following Adriamycin treatment revealed greater ultrastructural damage in cardiomyocyte mitochondria from DKO mice. Biochemical studies of cardiac tissues showed cytochrome c release and the increase in proapoptotic protein levels, suggesting that lack of TNF-alpha receptor I and II exacerbates Adriamycin-induced cardiac injury. The protective role of TNF receptor I and II was directly confirmed in isolated primary cardiomyocytes. Interestingly, following Adriamycin treatment, the levels of Fas decreased in the wild-type mice. In contrast, DKO mice had an increase in Fas levels and its downstream target, mitochondrial truncated Bid. These results suggested that TNF-alpha receptors play a critical role in cardioprotection by suppression of the mitochondrial-mediated associated cell death pathway.

Animals↗

PubMed2005

Screening of hepatocyte proteins binding to F protein of hepatitis C virus by yeast two-hybrid system.

AIM: To investigate the biological function of F protein by yeast two-hybrid system. METHODS: We constructed F protein bait plasmid by cloning the gene of F protein into pGBKT7, then recombinant plasmid DNA was transformed into yeast AH109 (a type). The transformed yeast AH109 was mated with yeast Y187 (alpha type) containing liver cDNA library plasmid in 2XYPDA medium. Diploid yeast was plated on synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) containing X-alpha-gal for selection and screening. After extracting and sequencing plasmids from positive (blue) colonies, we underwent sequence analysis by bioinformatics. RESULTS: Thirty-six colonies were selected and sequenced. Among them, 11 colonies were zymogen granule protein, 5 colonies were zinc finger protein, 4 colonies were zinc-alpha-2-glycoprotein, 1 colony was sialyltransferase, 1 colony was complement control protein factor I, 1 colony was vitronectin, and 2 colonies were new genes with unknown function. CONCLUSION: The yeast two-hybrid system is an effective method for identifying hepatocyte proteins interacting with F protein of hepatitis C virus. F protein may bind to different proteins.

Cell Line, Tumor↗

PubMed2005

The protective roles of nitric oxide and superoxide dismutase in adriamycin-induced cardiotoxicity.

OBJECTIVE: Treatment with adriamycin (ADR) is associated with cardiotoxicity mediated through the generation of superoxide (O2*-). Because nitric oxide (*NO) reacts with O2*-, generating peroxynitrite, we hypothesized that decreased *NO production would lead to protection in acute cardiac injury. METHODS: We investigated the role of decreased *NO levels in exacerbation of ADR-induced cardiotoxicity in vivo using iNOS (-/-) mice. Pathology, biochemical injury markers, and cardiac function were used to assess ADR-induced cardiac injury. RESULTS: Ultrastructural analysis demonstrated that iNOS (-/-) mice exhibited extensive cytoplasmic swelling and degeneration of mitochondria when compared to wildtype mice following treatment with ADR. Mice lacking iNOS exhibited a decrease in resting indices of cardiac function as well as an impairment in the positive inotropic actions of isoproterenol following treatment with ADR compared to nTg mice. Cardiac troponin, creatine phosphokinase, and lactate dehydrogenase levels were significantly increased after treatment in iNOS (-/-) mice as compared to controls and wildtype mice. CONCLUSIONS: These results indicate that a lack of *NO production by iNOS caused significantly enhanced cardiac injury. However, when iNOS (-/-) mice were crossed with manganese superoxide dismutase (MnSOD)-overexpressing animals, mitochondrial injury was ameliorated to the level of the wild type. These findings suggest that reduction of *NO levels mediated by ADR treatment leads to increased cardiac mitochondrial injury that can be attenuated by a compensatory increase in MnSOD.

Animals↗

PubMed2005

Induction of manganese superoxide dismutase (MnSOD) mediates cardioprotective effect of tamoxifen (TAM).

Tamoxifen (TAM), a synthetic nonsteroidal antiestrogen effectively and widely used for breast cancer treatment, is known to have antioxidant and cardioprotective effects, but whether the beneficial cardiovascular effect of TAM is linked to its antioxidant effect is unknown. In this study, we investigated the effect of TAM on the levels of manganese superoxide dismutase (MnSOD), a mitochondrial antioxidant enzyme, in cardiac tissues and cardiomyocytes. TAM treatment induced MnSOD expression in vitro and in vivo. Cardiomyocytes isolated from TAM-pretreated mice also had higher MnSOD levels and fewer apoptotic cells compared to cardiomyocytes from control mice after adriamycin (ADR) treatment. To further confirm the role of MnSOD in the protection against ADR in cardiomyocytes, we used cardiomyocytes isolated from MnSOD knock-out (MnSOD(+/-)), wild-type (NTg) and human MnSOD transgenic (TgH) mice. TUNEL assay indicated that the percentage of cells undergoing apoptosis after ADR treatment was significantly greater in MnSOD(+/-) than in NTg or TgH cardiomyocytes. 3-[4, 5-Dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay showed that basal level of mitochondrial function was lower in MnSOD(+/-) cardiomyocytes than in NTg or TgH, and that MnSOD(+/-) was more sensitive to ADR. ADR treatment increased caspase activity, which was significantly higher in MnSOD(+/-) than in NTg or TgH cardiomyocytes. These results suggested that TAM-induced MnSOD expression is at least, in part, contribute to the cardioprotective effects of TAM.

Animals↗

PubMed2005

Screening of genes of proteins interacting with p7 protein of hepatitis C virus from human liver cDNA library by yeast two-hybrid system.

AIM: To investigate the biological function of p7 protein and to look for proteins interacting with p7 protein in hepatocytes. METHODS: We constructed p7 protein bait plasmid by cloning the gene of p7 protein into pGBKT7, then transformed it into yeast AH109 (a type). The transformed yeast was mated with yeast Y187 (alpha type) containing liver cDNA library plasmid, pACT2 in 2XYPDA medium. Diploid yeast was plated on synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) containing x-alpha-gal for selection and screening. After extracting and sequencing of plasmids from blue colonies, we performed sequence analysis by bioinformatics. RESULTS: Fifty colonies were selected and sequenced. Among them, one colony was Homo sapiens signal sequence receptor, seven colonies were Homo sapiens H19, seven colonies were immunoglobulin superfamily containing leucine-rich repeat, three colonies were spermatid peri-nuclear RNA binding proteins, two colonies were membrane-spanning 4-domains, 24 colonies were cancer-associated antigens, four colonies were nucleoporin 214 ku and two colonies were CLL-associated antigens. CONCLUSION: The successful cloning of gene of protein interacting with p7 protein paves a way for the study of the physiological function of p7 protein and its associated protein.

Base Sequence↗

PubMed2005

Screening of hepatocyte proteins binding to complete S protein of hepatitis B virus by yeast-two hybrid system.

AIM: To investigate the biological function of complete S protein and to look for proteins interacting with complete S protein in hepatocytes. METHODS: We constructed bait plasmid expressing complete S protein of HBV by cloning the gene of complete S protein into pGBKT7, then the recombinant plasmid DNA was transformed into yeast AH109 (a type). The transformed yeast AH109 was mated with yeast Y187 (alpha type) containing liver cDNA library plasmid in 2XYPDA medium. Diploid yeast was plated on synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) containing X-alpha-gal for selection and screening. After extracting and sequencing of plasmids from positive (blue) colonies, we underwent sequence analysis by bioinformatics. RESULTS: Nineteen colonies were selected and sequenced. Among them, five colonies were Homo sapiens solute carrier family 25, member 23 (SLC25A23), one was Homo sapiens calreticulin, one was human serum albumin (ALB) gene, one was Homo sapiens metallothionein 2A, two were Homo sapiens betaine-homocysteine methyltransferase, three were Homo sapiens Na(+) and H(+) coupled amino acid transport system N, one was Homo sapiens CD81 antigen (target of anti-proliferative antibody 1) (CD81), three were Homo sapiens diazepam binding inhibitor, two colonies were new genes with unknown function. CONCLUSION: The yeast-two hybrid system is an effective method for identifying hepatocyte proteins interacting with complete S protein of HBV. The complete S protein may bind to different proteins i.e., its multiple functions in vivo.

Base Sequence↗

PubMed2005

Genes transactivated by hepatitis C virus core protein, a microarray assay.

AIM: To explore the new target genes transactivated by hepatitis C virus (HCV) core protein and to elucidate the pathogenesis of HCV infection. METHODS: Reverse transcribed cDNA was subjected to microarray assay. The coding gene transactivated by HCV core protein was cloned and analyzed with bioinformatics methods. RESULTS: The expressive vector of pcDNA3.1(-)-core was constructed and confirmed by restriction enzyme digestion and DNA sequencing and approved correct. mRNA was purified from HepG2 and HepG2 cells transfected with pcDNA3.1(-)-core, respectively. The cDNA derived was subjected to microarray assay. A new gene named HCTP4 was cloned with molecular biological method in combination with bioinformatics method. CONCLUSION: HCV core is a potential transactivator. Microarray is an efficient and convenient method for analysis of differentially expressed genes.

Carcinoma, Hepatocellular↗

PubMed2005

[Screening of HBeAgTP interacting proteins in hepatocytes with yeast-two hybrid technique].

OBJECTIVE: To screen proteins in hepatocytes interacting with HBeAg transactivated protein (HBeAgTP) with yeast-two hybrid technique for investigating the biological functions of HBeAgTP. METHODS: Suppression subtractive hybridization (SSH) and bioinformatics techniques were used for screening and cloning of the target genes transactivated by HBeAg. The HBeAgTP gene was amplified by polymerase chain reaction (PCR) and HBeAgTP bait plasmid was constructed with yeast-two hybrid system 3, and then transformed into yeast AH109. The transformed yeast mated with yeast Y187 containing liver cDNA library plasmid in 2 x YPDA medium. Diploid yeast was plated on synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) and synthetic dropout nutrient medium (SD/-Trp-Leu-His-Ade) containing X-gal for selecting two times and screening. After extracting and sequencing of plasmid from blue colonies, the results were analyzed by bioinformatics. RESULTS: HBeAgTP gene was successfully cloned and expressed in yeast cells. Fifteen genes in twenty-four positive colonies were obtained using yeast-two hybrid technique. CONCLUSION: HBeAgTP conjugated protein genes were successfully cloned, along with the genes involved in transcription and translation of proteins, immunoloregulation, materials and energy metabolism in vivo.

Hepatitis B e Antigens↗

PubMed2004

Chinese inpatients' subjective experiences of the helping process as viewed through examination of a nurses' focused, structured therapy group.

AIMS AND OBJECTIVES: This study examined Chinese inpatients' views on what aspects of a nurses' focused, structured therapy group worked to help their psychological and interpersonal problems and what traditional Chinese cultural values influenced their viewpoints. METHODS: Nine Chinese inpatients with mental illness participated in the four-session nurses' focused, structured therapy group. After they completed the last session of therapy, they were invited to participate in a structured interview and a semi-structured interview regarding their perceptions of the change mechanisms in nurses' focused, structured group therapy. The semi-structured interviews were recorded and transcribed to be further analysed according to the principal of content analysis. RESULTS: The results indicate that (i) all patients believed that a nurses' focused, structured group psychotherapy enhanced their interpersonal learning and improved the quality of their lives, (ii) traditional Chinese cultural values--those emphasizing the importance of maintaining harmonious interpersonal relationships--influenced the Chinese inpatients' expression of negative emotions in the group and their motivation on interpersonal learning. CONCLUSION: In conclusion, we found that transcultural modification for applying Western group psychotherapy in Chinese culture was needed. The modification included establishing a 'pseudo-kin' or 'own people' relationship among group members and the therapists, organizing warm-up exercises and structured activities, applying projective methods and focusing on the issues of interpersonal relationships and interpersonal problems. RELEVANCE TO CLINICAL PRACTICE: The small sample size of the present study raises questions regarding how representative the views of the sample are with respect to the majority of Chinese inpatients. Nevertheless, this preliminary study revealed a cultural aspect in nursing training that requires significant consideration in order to work effectively with Chinese patients.

Cultural Characteristics↗