Biomedical subjects

T Y Hsieh

Publications and source records attributed to T Y Hsieh.

14 recordsLinked to original sources

PubMed2004

Predominance of Th1 cytokine in peripheral blood and pathological tissues of patients with active untreated adult onset Still's disease.

OBJECTIVE: To determine the type 1 T helper (Th1)/type 2 T helper (Th2) balance in the peripheral blood (PB) and pathological tissues of patients with active untreated adult onset Still's disease (AOSD). METHODS: The percentages of interferon gamma (IFNgamma)- and interleukin (IL)4-producing Th cells in the PB of 20 patients with active untreated AOSD, 20 patients with active rheumatoid arthritis (RA), and 20 healthy controls were determined by intracellular staining and flow cytometry. Serum levels of IL18 and soluble IL2 receptor were measured by enzyme linked immunosorbent assay. Levels of IFNgamma and IL4 messenger (m) RNA expression were examined by real time quantitative polymerase chain reaction in biopsy specimens of evanescent rash and synovitis from 8 patients with AOSD. RESULTS: Significantly higher IFNgamma-producing Th cells and Th1/Th2 ratio in PB were found in patients with AOSD than in healthy controls. Percentages of IFNgamma-producing Th cells and Th1/Th2 ratio in PB correlated significantly with clinical activity score and serum IL18 levels in patients with AOSD. Increased ratio of Th1/Th2 cytokine transcripts was seen in the biopsy specimens of evanescent rash and synovitis from patients with AOSD compared with normal skin controls and patients with OA. Th cell cytokine pattern in PB and cytokine mRNA expression in synovium were similar for patients with AOSD and with RA. After 3 months' treatment, clinical remission was associated with a marked decrease in the percentages of cytokine-producing Th1 cells, but not of the Th2 cells. CONCLUSION: A predominance of Th1 cytokine may precipitate the pathogenesis of AOSD.

Adult↗

PubMed2002

Effects of cisapride on oesophageal transit of solids in patients with progressive systemic sclerosis.

In most patients with progressive systemic sclerosis (PSS) the oesophagus is affected. Reflux symptoms are most frequent, whilst dysphagia also occurs. Cisapride, a prokinetic agent, may enhance motility along the gastrointestinal tract. The effects of cisapride on oesophageal transit were evaluated in 12 PSS patient using a solid-phase radionuclide oesophageal transit study. Each PSS patient was given cisapride 10 mg or placebo orally three times a day in a random, double-blind, crossover fashion. The results show that cisapride does not seem to have any impact on oesophageal transit in patients with PSS.

Administration, Oral↗

PubMed2001

Colonic transit disorders in systemic sclerosis.

Systemic sclerosis (SS) alters smooth muscle function throughout the gastrointestinal tract, the oesophagus being the segment most often involved. Involvement of the colon, though less common, may lead to life-threatening complications. We studied 23 unselected patients with SS and 20 age-matched healthy controls using radionuclide colon transit studies. The geometric centre (GC) at 4 and 24 hours was used to summarise overall transit in the colon. In patients with SS, colon transit was delayed (GC4: 0.39 +/- 0.36 vs 0.85 +/- 0.45; P=0.001) (GC24: 1.68 +/- 0.9 vs 2.58 +/- 1.08; P=0.006). These findings suggest that delayed colon transit is common in patients with SS.

Adolescent↗

PubMed2001

Aspirin differentially regulates endotoxin-induced IL-12 and TNF-alpha production in human dendritic cells.

OBJECTIVE: In the development of autoimmune diseases, dendritic cells (DC) play critical roles. Here, we examined the effect of aspirin on lipopolysaccharide (LPS)-induced DC activation. METHODS: The monocyte-derived DC were established. The cytokine production was measured by ELISA, reverse transcriptase/polymerase chain reaction, or intracellular staining analyzed by flow cytometry. The expression of cell surface molecules was determined by flow cytometry. RESULTS: Aspirin inhibited LPS-induced DC maturation and costimulatory molecules expression. Aspirin, at therapeutic concentrations, also decreased LPS-induced IL-12 and IL-10 production. In contrast, the LPS-induced TNF-alpha production was enhanced by aspirin. The differential effects of aspirin on IL-12 and TNF-alpha production may not be due to down-regulation of cyclooxygenase activities. CONCLUSION: The various effects of aspirin on LPS-stimulated DC may influence the understanding of the diverse immunomodulatory mechanisms of this anti-inflammatory drug.

Aspirin↗

PubMed2000

Heterogeneous nuclear ribonucleoproteins as regulators of gene expression through interactions with the human thymidine kinase promoter.

In search for nuclear proteins that interact with the human thymidine kinase (htk) promoter, we discovered that p37AUF, a hnRNP C-like protein, and hnRNP A1, both members of the heterogeneous ribonucleoprotein family, can bind with high affinity to an ATTT sequence motif contained within the cell cycle regulatory unit (CCRU). We report here that over-expression of p37AUF stimulates gene expression mediated by the htk promoter in a promoter-sequence specific manner, whereas hnRNP A1 suppresses it. Both recombinant p37AUF and hnRNP A1 can bind the htk CCRU, suggesting that their binding to the DNA target does not require additional cellular components. We further discovered that hnRNP K is a potent suppressor of htk mediated gene activity. However, its mechanism of action is mediated through protein-protein interaction, since hnRNP K itself cannot bind the htk CCRU but can competitively inhibit the binding of other hnRNPs. The binding site for the hnRNPs on the htk CCRU is not required for S-phase induction of the htk promoter. However, in stable but not transient transfectants, the mutation of the hnRNP binding site results in 5- to 10-fold reduction of htk mediated gene activity in synchronized and exponentially growing cells. Collectively, these findings support emerging evidence that hnRNPs, in addition to their traditional role in RNA biogenesis, could be regulators of gene expression through direct DNA binding or interaction with other proteins.

Amino Acid Sequence↗

PubMed2000

Chinese alcoholic patients with esophageal cancer are genetically different from alcoholics with acute pancreatitis and liver cirrhosis.

OBJECTIVE: It is a mystery why some alcoholic patients acquire certain organ-specific complications of alcoholism, whereas other alcoholic patients acquire different ones. The aim of this study was to investigate the differences among Chinese alcoholic patients with esophageal cancer, acute pancreatitis, and liver cirrhosis by studying the genetic polymorphisms of ADH2, ADH3, ALDH2, and P4502E1. METHODS: Liver alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), and cytochrome P4502E1 (P4502E1) are polymorphic at the ADH2, ADH3, and ALDH2 loci and the 5'-flanking region of the P4502E1. Using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, we determined the polymorphism of the above-mentioned alcohol metabolizing genes in 59 alcoholics with carcinoma of the esophagus (alcoholic esophageal Ca), 87 acute alcoholic pancreatitis patients, 116 alcoholics with liver cirrhosis (alcoholic cirrhosis), 19 alcoholics with both liver cirrhosis and acute pancreatitis (alcoholic P plus C), and 241 nonalcoholic patients. RESULTS: The results showed that the allele frequency of ALDH2*2 was significantly higher in the alcoholic esophageal Ca group than in the alcoholic pancreatitis and alcoholic cirrhosis groups. The allele frequency of ADH2*1 was significantly higher in the alcoholic esophageal Ca patients than in nonalcoholic control groups. The ALDH2*2 was significantly lower in alcoholic groups (except the alcoholic esophageal Ca group) than in nonalcoholic control groups. The allele frequencies of ADH2*1 and ALDH2*2 are higher in alcoholic patients with esophageal Ca than alcoholic patients without it. The genotype distribution of P4502E1, detected by RsaI and PstI, was not different among alcoholic patients with different organ diseases. CONCLUSIONS: The allele frequency of ADH2*1 and ALDH2*1 are different among subpopulations of alcoholics, suggesting that alcoholic patients with different specific types of organ damage are genetically different. The Chinese alcoholic patients with the ADH2*1 and ALDH2*2 allele are more susceptible to esophageal Ca.

Adult↗

PubMed2000

Interleukin-8 secretion by cultured oral epidermoid carcinoma cells induced with nicotine and/or arecoline treatments.

Interleukin-8 (IL-8) is one of the multifunctional cytokines that can play a role on immune and inflammatory activities. Other in vitro observations indicated that IL-8 is a growth factor for keratinocytes. However, as the role of IL-8 in oral cancer cells is unclear, this study is thus designed to examine IL-8 secretion in cultured oral epidermoid carcinoma KB CCL17 cells treated with nicotine and/or arecoline. The cultures were treated with nicotine (1 or 100 microM) and arecoline (1 or 100 microM), alone or both, for 72 hrs. Enzyme-linked immunosorbent assay (ELISA) was used to examine IL-8 concentrations in culture supernatants. A repeated measure analysis of variance was used to identify differences among the treatments. Nicotine and arecoline, single or combined treatment, increased IL-8 secretion in KB CCL17 cells. When monoclonal 1 microgram/ml of antibody was added against IL-1 alpha or IL-1 beta in the treatment, IL-8 concentration significantly decreased compared with the non-added one. Exposure of cells to antibody against IL-1 alpha or IL-1 beta showed no significant increase in cell growth as compared with the control (medium alone). However, incubation of cells for 72 hrs in the presence of nicotine and/or arecoline treatments and antibody against IL-1 alpha or IL-1 beta significantly increased cell growth as compared with the antibody free one. It was concluded that IL-8 secretion by KB CCL17 cells may be partially mediated by IL-1 which could inhibit the KB CCL17 cell growth. Thus, IL-8 may be a vital participant in the cascade of interacting cytokines during smoking and areca quid chewing, inducing inflammation in oral cancer.

Antibodies, Monoclonal↗

PubMed1999

The multifunctional herpes simplex virus IE63 protein interacts with heterogeneous ribonucleoprotein K and with casein kinase 2.

Herpes simplex virus type 1 (HSV-1), the prototype alpha-herpesvirus, causes several prominent diseases. The HSV-1 immediate early (IE) protein IE63 (ICP27) is the only regulatory gene with a homologue in every mammalian and avian herpesvirus sequenced so far. IE63 is a multifunctional protein affecting transcriptional and post-transcriptional processes, and it can shuttle from the nucleus to the cytoplasm. To identify interacting cellular proteins, a HeLa cDNA library was screened in the yeast two-hybrid system using IE63 as bait. Several interacting proteins were identified including heterogeneous nuclear ribonucleoprotein K (hnRNP K), a multifunctional protein like IE63, and the beta subunit of casein kinase 2 (CK2), a protein kinase, and interacting regions were mapped. Confirmation of interactions was provided by fusion protein binding assays, co-immunoprecipitation from infected cells, and CK2 activity assays. hnRNP K co-immunoprecipitated from infected cells with anti-IE63 serum was a more rapidly migrating subfraction than hnRNP K immunoprecipitated by anti-hnRNP K serum. Using anti-IE63 serum, both IE63 and hnRNP K were phosphorylated in vitro by CK2, while in immunoprecipitates using anti-hnRNP K serum, IE63 but not hnRNP K was phosphorylated by CK2. These data provide important new insights into how this key viral regulatory protein exerts its functions.

Animals↗

PubMed1998

Hepatitis C virus core protein interacts with heterogeneous nuclear ribonucleoprotein K.

Hepatitis C virus (HCV) core protein, a component of viral nucleocapsid, has been shown to modulate cellular and viral promoter activities. To identify potential cellular targets for HCV core protein, a human liver cDNA library was screened for core-interacting proteins using the yeast two-hybrid system. Among the proteins identified was heterogeneous nuclear ribonucleoprotein K (hnRNP K), which has been demonstrated to be a transcriptional regulator. The interaction of HCV core protein with hnRNP K was confirmed by glutathione S-transferase fusion protein binding assay, protein-protein blotting assay, and coimmunoprecipitation in vitro and in vivo. Additionally, these two proteins were shown to be partially colocalized in the nucleus. The hnRNP K-binding site in HCV core protein was mapped to the region from amino acid residues 25-91, a hydrophilic area near the N terminus. The HCV core protein-binding domain was located within amino acid residues 250 to 392, which contain the three proline-rich domains, of hnRNP K. Furthermore, HCV core protein relieved the suppression effect of hnRNP K on the activity of the human thymidine kinase gene promoter. The specific binding of HCV core protein to hnRNP K suggests that multiple functions of hnRNP K may be disrupted by the core protein during HCV infection and thus explains, in part, the pathogenesis of HCV.

Amino Acid Sequence↗

PubMed1998

Hepatitis delta antigen mediates the nuclear import of hepatitis delta virus RNA.

Hepatitis delta virus (HDV) RNA replicates in the nuclei of virus-infected cells. The mechanism of nuclear import of HDV RNA is so far unknown. Using a fluorescein-labeled HDV RNA introduced into partially permeabilized HeLa cells, we found that HDV RNA accumulated only in the cytoplasm. However, in the presence of hepatitis delta antigen (HDAg), which is the only protein encoded by HDV RNA, the HDV RNA was translocated into the nucleus, suggesting that nuclear import of HDV RNA is mediated by HDAg. Deletion of the nuclear localization signal (NLS) or RNA-binding motifs of HDAg resulted in the failure of nuclear import of HDV RNA, indicating that both the NLS and an RNA-binding motif of HDAg are required for the RNA-transporting activity of HDAg. Surprisingly, any one of the three previously identified RNA-binding motifs was sufficient to confer the RNA-transporting activity. We have further shown that HDAg, via its NLS, interacts with karyopherin alpha2 in vitro, suggesting that nuclear import of the HDAg-HDV RNA complex is mediated by the karyopherin alpha2beta heterodimer. The nuclear import of HDV RNA may be the first biological function of HDAg in the HDV life cycle.

Binding Sites↗

PubMed1997

Hepatitis C virus core protein interacts with the cytoplasmic tail of lymphotoxin-beta receptor.

Hepatitis C virus (HCV) core protein is a multifunctional protein. We examined whether it can interact with cellular proteins, thus contributing to viral pathogenesis. Using the HCV core protein as a bait to screen a human liver cDNA library in a yeast two-hybrid screening system, we have isolated several positive clones encoding cellular proteins that interact with the HCV core protein. Interestingly, more than half of these clones encode the cytoplasmic domain of lymphotoxin-beta receptor (LT betaR), which is a member of the tumor necrosis factor receptor family. Their binding was confirmed by in vitro glutathione S-transferase fusion protein binding assay and protein-protein blotting assay to be direct and specific. The binding sites were mapped within a 58-amino-acid region of the cytoplasmic tail of LT betaR. The binding site in the HCV core protein was localized within amino acid residues 36 to 91 from the N terminus, corresponding to the hydrophilic region of the protein. In mammalian cells, the core protein was found to be associated with the membrane-bound LT betaR. Since the LT betaR is involved in germinal center formation and developmental regulation of peripheral lymphoid organs, lymph node development, and apoptotic signaling, the binding of HCV core protein to LT betaR suggests the possibility that this viral protein has an immunomodulating function and may explain the mechanism of viral persistence and pathogenesis of HCV.

Binding Sites↗

PubMed1996

Regulation of growth, PSA/PAP and androgen receptor expression by 1 alpha,25-dihydroxyvitamin D3 in the androgen-dependent LNCaP cells.

The involvement of vitamin D in prostate carcinogenesis was investigated using the human prostatic LNCaP cells. Incubation of the LNCaP with 100 nM 1 alpha,25-dihydroxyvitamin D3 for 2 days resulted in a 30-40% suppression of cell growth, which was accompanied by a greater than 70% down-regulated expression of the proliferating cell nuclear antigen (PCNA). The intracellular and secreted forms of PSA showed a 2-fold increase following a 48 h culture in the presence of vitamin D3. The vitamin D3-elicited PSA increases were preceded by an induction of androgen receptor (AR) expression, as measured by Western blot analysis and by binding assays using [3H]R1881 as the ligand. These results are consistent with the hypothesis that the growth inhibitory effects of vitamin D3 is partially mediated through its ability to modulate PCNA expression. Moreover, vitamin D3 may effect increases in PSA expression indirectly by up-regulating androgen receptors.

Acid Phosphatase↗

PubMed1996

Hydatid cysts in the liver.

A 67-year-old Taiwanese woman with multilocular hydatid cysts of the liver presented with a 5-month history of intermittent right upper abdominal discomfort. Abdominal ultrasonography and computed tomography showed multiple cysts in both lobes of the liver. Subsequent selective celiac angiography revealed an avascular space-occupying lesion in the right lobe. She underwent a radical excision of the cyst by total closed (without opening the wall) cystopericystectomy over segments 4, 5 and 6. Histologic study of the lesions showed three structural components: 1) an outer acellular laminated membrane, 2) a thin nucleated germinal membrane and 3) several protoscolices with Echinococcus granulosus suckers. The patient has been well for 5 years since her discharge. Although hydatid cysts of the liver are extremely rare in Taiwan, they may cause life-threatening complications and mortality. Making a preoperative diagnosis is important and is only possible if this rare disease is kept in mind.

Aged↗

PubMedDate not supplied

Solid phase radionuclide esophageal transit in mixed connective tissue disease.

Esophageal motility was studied in 24 patients with mixed connective tissue disease (MCTD) and 20 control subjects by the solid phase radionuclide esophageal transit study. A computer routine modified from Klein and Russel was used. Total mean transit time, regional mean transit time, residual fraction after first swallow, and retrograde index increased significantly in MCTD patients compared with normal control subjects. An abnormal total mean transit time occurred in 84% (20 of 24) of the patients with MCTD. Our results confirmed that delayed esophageal transit is common in patients with MCTD.

Adolescent↗