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Biomedical subjects

C Y Tsai

Publications and source records attributed to C Y Tsai.

At least 19 recordsLinked to original sources

Anti-myeloperoxidase antibodies enhance phagocytosis, IL-8 production, and glucose uptake of polymorphonuclear neutrophils rather than anti-proteinase 3 antibodies leading to activation-induced cell death of the neutrophils.

Anti-neutrophil cytoplasmic antibodies (ANCA) not only are triggered by target protein myeloperoxidase (MPO) and proteinase 3 (PR3) of polymorphonuclear neutrophil (PMN) but also react with primed PMN to exert the inflammatory process in vasculitis syndrome. To clarify the crucial role of PMN in ANCA-associated vasculitis and the related mechanism, PMN was cultured with monoclonal antibody MPO-ANCA and PR3-ANCA to determine the function of phagocytosis, Interleukin- 8 (IL-8) production, glucose uptake, and TNF-related apoptosis induced ligand (TRAIL) production. The spontaneous membrane expression of MPO and PR3 on PMN could be significantly increased by lipopolysaccharide (LPS) and TNF-alpha, but not by IL-8 or GRO-alpha. The PMN-stimulating activity of ANCA was demonstrated by enhancing phagocytosis, IL-8 production, and glucose uptake that was more prominent by MPO-ANCA. The PMN stimulation by ANCA was not through protein kinase, H2O2, or superoxide anion radicals as their inhibitors exerted no effect on ANCA-mediated activation. On the other hand, ANCA also accelerated PMN apoptosis and increased TRAIL production. These results demonstrate that activation-induced cell death (AICD) mechanism could be initiated in PMN with existence of ANCA. In conclusion, MPO-ANCA is more potent in stimulating PMN than PR3-ANCA. ANCA-activated PMN is not only responsible for the amplified inflammatory process in blood vessel but also initiates immune circuit via triggered macrophage/monocyte by apoptotic PMN through the mechanism of AICD elicited by ANCA.

Antibodies, Antineutrophil Cytoplasmic↗

The effect of etanercept on anti-cyclic citrullinated peptide antibodies and rheumatoid factor in patients with rheumatoid arthritis.

OBJECTIVE: To evaluate the changes in anti-cyclic citrullinated peptide antibodies (anti-CCP) and rheumatoid factor (RF) following etanercept treatment in patients with rheumatoid arthritis. METHODS: The study included 90 patients with rheumatoid arthritis who failed treatment with disease modifying antirheumatic drugs (DMARDs). All patients were allowed to continue treatment with DMARDs; 52 of them received etanercept as a twice weekly 25 mg subcutaneous injection for three months, and the others did not. Serum samples were collected at baseline and one month intervals during the treatment course. The serum levels of anti-CCP and RF were tested by enzyme linked immunosorbent assay and nephelometry, respectively. RESULTS: At baseline, 45 of the 52 etanercept treated patients (86.5%) and 32 of the 38 controls (84.2%) were positive for anti-CCP. Tests for RF were positive in 78.9% and 84.2% of patients with or without etanercept treatment, respectively. The serum levels of anti-CCP and RF decreased significantly after a three month etanercept treatment (p = 0.007 and p = 0.006, respectively). The average decrease from baseline calculated for each individual patient in the etanercept treated group was 31.3% for anti-CCP and 36% for RF. The variation in anti-CCP was positively correlated with the variation in disease activity, swollen and tender joint counts, RF, and C reactive protein. CONCLUSIONS: Etanercept combined with DMARDs leads to a much greater decrease than DMARDs alone in the serum levels of anti-CCP and RF in rheumatoid arthritis, compatible with a reduction in clinical disease activity.

Acute-Phase Proteins↗

Phasic cardiovascular responses to mevinphos are mediated through differential activation of cGMP/PKG cascade and peroxynitrite via nitric oxide generated in the rat rostral ventrolateral medulla by NOS I and II isoforms.

The organophosphate insecticide mevinphos (Mev) acts on the rostral ventrolateral medulla (RVLM), where sympathetic vasomotor tone originates, to elicit phasic cardiovascular responses via nitric oxide (NO) generated by NO synthase (NOS) I and II. We evaluated the contribution of soluble guanylyl cyclase (sGC)/cyclic guanosine monophosphate (cGMP)/protein kinase G (PKG) cascade and peroxynitrite in this process. PKG expression in ventrolateral medulla of Sprague-Dawley rats manifested an increase during the sympathoexcitatory phase (Phase I) of cardiovascular responses induced by microinjection of Mev bilaterally into the RVLM that was antagonized by co-administration of 7-nitroindazole or Nomega-propyl-L-arginine, two selective NOS I inhibitors or 1-H-[1,2,4]oxadiaolo[4,3-a]quinoxalin-1-one (ODQ), a selective sGC antagonist. Co-microinjection of ODQ or two PKG inhibitors, KT5823 or Rp-8-Br-cGMPS, also blunted the Mev-elicited sympathoexcitatory effects. However, the increase in nitrotyrosine, a marker for peroxynitrite, and the sympathoinhibitory circulatory actions during Phase II Mev intoxication were antagonized by co-administration of S-methylisothiourea, a selective NOS II inhibitor, Mn(III)-tetrakis-(4-benzoic acid) porphyrin, a superoxide dismutase mimetic, 5,10,15,20-tetrakis-N-methyl-4'-pyridyl)-porphyrinato iron (III), a peroxynitrite decomposition catalyst, or L-cysteine, a peroxynitrite scavenger. We conclude that sGC/cGMP/PKG cascade and peroxynitrite formation may participate in Mev-induced phasic cardiovascular responses as signals downstream to NO generated respectively by NOS I and II in the RVLM.

Animals↗

HLA-B60 and B61 are strongly associated with ankylosing spondylitis in HLA-B27-negative Taiwan Chinese patients.

OBJECTIVES: Carriage of HLA-B60 has been shown to increase the risk of ankylosing spondylitis (AS) in B27-positive Caucasian patients, but the association in B27-negative cases is less certain. This study assessed HLA class I gene associations in Chinese HLA-B27-negative AS patients. METHODS: Forty-one Chinese HLA-B27-negative AS patients fulfilling the modified New York diagnostic criteria for AS were recruited, and 11 383 HLA-B27-negative blood donors were used for comparison. HLA-A and -B typing was done with the microlymphocytotoxicity assay. RESULTS: Among the B27-negative AS patients, 21 were male and 20 were female. Of HLA-B alleles, only B60 and B61 significantly increased susceptibility to AS in HLA-B27-negative patients (P<0.001). CONCLUSIONS: In Taiwan Chinese, carriage of B60 is increased in HLA-B27-negative AS patients. The association between B61 and HLA-B27-negative AS patients has not been reported previously. Whether the gene involved is HLA-B60 or B61 or another gene in linkage disequilibrium with these genes is unknown.

Adult↗

Anti-dsDNA antibody up-regulates interleukin 6, but not cyclo-oxygenase, gene expression in glomerular mesangial cells: a marker of immune-mediated renal damage?

OBJECTIVE AND DESIGN: To determine whether anti-double stranded DNA antibody (anti-dsDNA) can affect the synthesis of eicosanoids and cytokines in rat glomerular mesangial cells (RMC). MATERIALS OR SUBJECTS: Glomerular mesangial cells were isolated and subcultured from Sprague-Dawley rats. Monoclonal anti-dsDNA (12B3 clone) was derived from autoimmune MRL-lpr/lpr mouse by hybridoma technology. METHODS: The mRNA expression of cyclo-oxygenase type 1 (COX-1), type 2 (COX-2), Th1 (IL-2 and IFN-gamma)/Th2 (IL-4 and IL-10) and proinflammatory (IL-6 and TNF-alpha) and anti-inflammatory (TGF-beta) cytokines of RMC +/- anti-dsDNA was detected by RT-PCR. The PGE2 production by RMC +/- anti-dsDNA was measured by ELISA. The statistical significance was assessed by non-parametric Wilcoxon signed rank test. RESULTS: We found RMC spontaneously expressed COX-1, but not COX-2. The incubation of RMC with anti-dsDNA (50 ng/ml) did not affect COX expression and PGE2 production by RMC. RMC also spontaneously expressed IL-6, TNF-alpha and TGF-beta mRNA. However, only IL-6 was up-regulated by anti-dsDNA. CONCLUSIONS: Increased IL-6 expression in RMC may become a marker of anti-dsDNA-mediated immune damage of mesangial cells.

Animals↗

Monoclonal anti-double stranded DNA antibody is a leucocyte-binding protein to up-regulate interleukin-8 gene expression and elicit apoptosis of normal human polymorphonuclear neutrophils.

OBJECTIVES: To determine whether anti-double stranded DNA (anti-dsDNA) autoantibody could bind and affect the functions of normal human polymorphonuclear neutrophils (PMN). METHODS: Normal human PMN were incubated with different concentrations of a monoclonal mouse anti-dsDNA antibody (12B3) or mouse isotype-matched IgG2a. The binding of anti-dsDNA and PMN was measured by flow cytometry and interleukin-8 (IL-8) gene expression in PMN was detected by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR). PMN apoptosis was justified by morphological changes. The cognate antigen(s) of anti-dsDNA on the PMN surface was identified by membrane biotinylation, immunoprecipitation and Western blot. RESULTS: The binding of PMN with anti-dsDNA was much higher than with non-specific mouse IgG2a (70.8 vs 2.0%). Anti-dsDNA at concentrations higher than 12.5 ng/ml significantly enhanced the production and mRNA expression of IL-8 by PMN. However, anti-dsDNA facilitated PMN apoptosis after 3 h incubation. Western blot analysis of biotinylated PMN cell lysates demonstrated that a 50-52 kDa membrane molecule is the cognate antigen of anti-dsDNA. CONCLUSIONS: Anti-dsDNA autoantibody up-regulates IL-8 gene expression and elicits activation-induced cell death (AICD) of human PMN via binding to a 50-52 kDa membrane-expressed molecule.

Animals↗

Surgical treatment for rectal prolapse.

BACKGROUND: The problem of full-thickness rectal prolapse is formidable, with no clear predominant treatment of choice. Several operations have been proposed to correct rectal prolapse which can be divided into transabdominal and perineal procedures. METHODS: From September 1982 to October 1999, 32 patients with rectal prolapse were treated with surgical procedures. There were 16 males and 16 females with a mean age of 58.3 years (Range 17-89). Forteen patients received rectopexy procedure, 6 patients received sigmoidectomy, 6 patients received perineal rectosigmoidectomy, 1 patient received Delorme procedure, 1 patient received Thiersch procedure and 4 patients received laparoscopic-assisted sigmoidectomy. The median follow up times were 7.5 years. RESULTS: In the rectopexy group, complication occurred in one patient (7.1%) and one patient recurred (7.1%). In the sigmoidectomy group, there were no complication but one patient recurred (10%). In the perineal rectosigmoidectomy group, there were no complication, but one patient recurred (16.7%). The total complication rate were 3.1% and total recurrence rate were 9.3%. CONCLUSIONS: Although, the best operation for rectal prolapse remains a controversial subject, we believe that laparoscopic-assisted sigmoidectomy offers a promising new option for the treatment of rectal prolapse.

Adolescent↗

Association of pityriasis rosea with human herpesvirus-6 and human herpesvirus-7 in Taipei.

BACKGROUND AND PURPOSE: Pityriasis rosea (PR) is a common papulosquamous skin disease with unknown etiology. The possible relationship of PR with human herpesvirus infection (HHV) has been extensively studied. This study used the polymerase chain reaction (PCR) to investigate the presence of human herpesvirus 6 and 7 (HHV-6 and HHV-7) in 41 PR patients from two hospitals in Northern Taiwan. The epidemiologic features of PR in patients were also studied. METHODS: A total of 41 PR patients (11 males, 30 females) were enrolled in this study from April 1999 to March 2000. PCR of skin biopsy specimens from 24 PR patients was used to identify the existence of HHV-6 and HHV-7. Viral culture from PR biopsy specimens was also performed. Blood from these patients was sampled for Venereal Disease Research Laboratory tests. Skin biopsies from 20 age- and sex-matched controls with other skin diseases were also subjected to PCR study. RESULTS: The ages of the 41 PR patients ranged from 8 to 62 years. An increased incidence (17/41) of PR episodes was observed during the spring. Both HHV-6 and HHV-7 DNA was below the limit of detection in all biopsy specimens from patients and healthy controls. Viral culture for HHV was negative in all patients. CONCLUSION: The epidemiologic features of PR in this series are comparable to other studies except for an exaggerated female predominance (male:female ratio 1:2.7). Our data indicate a lack of association between HHV-6 and HHV-7 infection and PR.

Adolescent↗

Lymphovascular clearance in laparoscopic surgery of cancer in low rectum.

BACKGROUND: The success of laparoscopic biliary surgery has encouraged application of laparoscopic surgery in colorectal disease. There are some questions regarding laparoscopic colorectal surgery, especially for colorectal cancer. Most important is whether adequate resection of colorectal malignancy can be achieved. A retrospective study was performed to evaluate the pathology of resected specimens following laparoscopic surgery and that following open surgery in cancer of the low rectum. Comparing the number of lymph nodes in specimens, we could then prove whether laparoscopic surgery can provide adequate clearance as well as open surgery and if laparoscopic surgery has no difference in comparison with open surgery. METHODS: The retrospective study was performed to evaluate the pathology of resected specimens following laparoscopic surgery and that following open surgery in cancer of the low rectum. Data regarding patient details and tumor pathology were obtained by case-note review and from Taichung Veterans General Hospital from July, 1998 to April, 1999. There were nine patients with rectal carcinoma in the low rectum who received laparoscopic surgery, 7 male and 2 female. The control group had 8 patients, 7 male and 1 female, with similar tumor location who received similar operation with open method by the same surgical team in the same period. The average age was 67.7 years in the laparoscopic group and 67.4 years in the control group. The characteristics of tumor and the location of tumor were well matched between these two groups. RESULTS: All of the resected specimens in the two groups were free of tumor in margin of clearance. The average number of lymph nodes harvested was 13 in the laparoscopic group and 9.4 in the open group. CONCLUSIONS: Although the case number was not adequate, the clinical implication is obvious. Laparoscopic surgery in cancer of the low rectum allows lymphovascular clearance even better than that is afforded by open surgery.

Adult↗

The in vitro immunomodulatory effects of sulfasalazine on human polymorphonuclear leukocytes, mononuclear cells, and cultured glomerular mesangial cells.

Sulfasalazine (SSA) was investigated for its effects on phagocytic activity of normal human polymorphonuclear neutrophils (PMN), proliferation of mononuclear cells (MNC) and cultured glomerular mesangial cells. At concentrations from 25 to 100 microM, it inhibited phagocytic activity of PMN and the 3H-thymidine incorporation of phytohemagglutinin (PHA)-stimulated human MNC in a dose-dependent manner. At comparable concentrations, sulfapyridine and 5-aminosalicylic acid, two of its major metabolites, did not show similar effects. SSA exhibited an inhibitory effect on both mouse and rat mesangial cells but at rather higher concentrations (0.5 mM). Excretion of interleukin (IL)-8 by lipopolysaccharide (LPS)-stimulated PMN was also markedly deterred in a dose-dependent manner but excretion of IL-8 by LPS-stimulated MNC was not interfered by SSA. Production of tumor necrosis factor (TNF)-alpha and IL-1beta by mouse mesangial cells was not blocked by SSA but production of IL-4 by these cells was inhibited by it (>0.1 mM). Inhibition of MNC was not due directly to cytotoxic effect of SSA on these cells as shown by fluorescein diacetate stain. Collectively, SSA inhibits phagocytosis and IL-8 excretion by PMN as well as mitogen-stimulated MNC reaction. On the other hand, at high concentrations, it inhibits glomerular mesangial cells and their IL-4 excretion but not TNF-alpha and IL-1beta excretion. These results can account for minimal nephrotoxic characteristic of SSA and suggest that it may be helpful in the treatment of immune-mediated glomerulonephritis.

Adjuvants, Immunologic↗

Polyclonal anticardiolipin antibodies purified from sera of patients with active systemic lupus erythematosus induce apoptosis of the cultured glomerular mesangial cells.

OBJECTIVE: To test the effect of anticardiolipin antibodies (aCL) on cultured glomerular mesangial cells with regard to their expression of apoptosis-related genes. METHODS: aCL purified from active lupus sera by cardiolipin micelles were incubated with cultured rodent mesangial cells (RMC). Morphological changes of the RMC were observed. The genomic DNA was extracted for the detection of apoptosis. The total cell RNA was extracted for detection of Fas, c-myc, p53, and bcl-2 transcripts by reverse transcription-polymerase chain reaction. RESULTS: aCL (100 GPL-U/0.1 mg protein/ml) bound to RMC more prominent than human IgG (100 microg/ml). The antibodies suppressed RMC proliferation in a dose-dependent manner. The RMC were undergoing apoptosis as evidenced by morphologic changes, fluoresceinannexin V staining and appearance of nucleosome-sized DNA fragments. RMC spontaneously express p53 and c-myc but not Fas or bcl-2. aCL (100 GPL-U/ml) enhanced the expression of Fas but not other apoptosis-related genes and suppressed the intracellular tyrosine phosphorylation. CONCLUSIONS: Binding of aCL can induce apoptosis of the RMC. The aCL may be implicated in the pathogenesis of lupus nephritis.

Animals↗

Increased excretions of beta2-microglobulin, IL-6, and IL-8 and decreased excretion of Tamm-Horsfall glycoprotein in urine of patients with active lupus nephritis.

Tubulointerstitial nephritis is a less frequently recognized but important complication of systemic lupus erythematosus. We have investigated the cytokine beta2-microglobulin (beta2M) and Tamm-Horsfall glycoprotein (THG) excretions in the urine of systemic lupus erythematosus patients to identify indices for evaluation of tubulointerstitial inflammation in lupus nephritis (LN). Daily urine was collected from 15 patients with active LN, from 12 patients with inactive LN, and from 17 normal subjects. The amounts of soluble interleukin (IL) 2 receptor, IL-6, IL-8, beta2M, and THG in urine were measured. Beta2M and THG were regarded as indicators of proximal and distal renal tubule function, respectively. The urinary excretions of IL-6 and IL-8 were significantly higher in patients with active LN than in those with inactive LN and in normal individuals. The excretion of soluble IL-2 receptor in all three groups of subjects was not significantly different. On the other hand, the excretion of beta2M in patients with LN was significantly higher than that in normal individuals. The excretion of beta2M in patients with active or inactive LN was not significantly different. The THG excretion was lower in patients with active LN and tubulointerstitial inflammation as compared with patients with inactive LN or normal individuals. Six patients underwent pulse cyclophosphamide therapy during the course of experiments. Five of them showed a decrease in IL-8 and IL-6 excretions in urine after the treatment. The excretions of beta2M and THG in urine, in addition to IL-6 and IL-8, can reflect the renal inflammatory activity in patients with lupus tubulointerstitial nephritis as well as in those having lupus glomerulonephritis.

Case-Control Studies↗

Calcified schwannoma of the orbit and differential diagnosis of orbital calcification.

Calcified schwannoma of the orbit is rarely reported in the world literature. A 38-year-old Chinese male presented with a 5-year history of slow progressive left-sided axial proptosis. A smooth, retrobulbar and intracornal mass with central calcification and high internal reflectivity was found on computed tomography and sonographic study. From the clinical and radiologic features, the presumptive diagnosis of orbital cavernous hemangioma or meningioma was made and orbitotomy with tumor exicision was performed. Tumor excision revealed the rare diagnosis of calcified schwannoma. The differential diagnoses of a calcified orbital mass and the radiologic and clinical findings of the calcified schwannoma are described and discussed.

Adult↗

Interleukin-13 increases prostaglandin E2 (PGE2) production by normal human polymorphonuclear neutrophils by enhancing cyclooxygenase 2 (COX-2) gene expression.

OBJECTIVE: To investigate whether interleukin-13 (IL-13) can affect arachidonic acid metabolism and phagocytic activity of normal human polymorphonuclear neutrophils (PMN). METHODS: Normal human PMN (1 x 10(6) cells/ml) were incubated with different concentrations of IL-13 (0.1-10 ng/ml) for a variety of times (30-120 min). Phagocytosis and intracellular cyclooxygenase-2 (COX-2) were detected by flow cytometry. The expression of COX-1 and COX-2 mRNA was detected by RT-PCR. The concentration of PGE2 in the PMN cultured supernatants was determined by EIA. RESULTS: We found that IL-13 at an optimal concentration of 1 ng/ml significantly enhanced COX-2 gene expression and PGE2 production (121.57 +/- 22.17 pg/ml in IL-13 stimulation vs. 73.16 +/- 11.72 pg/ml in controls) by PMN. In addition, IL-13 stimulated PMN phagocytosis via increased complement receptor type 1 (CR1) and type 3 (CR3), but not IgG Fcgamma receptor type 3 (FcgammaRIII). The cytoplasmic neutral esterase activity of PMN was also enhanced by IL-13 stimulation for 24 h. CONCLUSIONS: These results suggest that IL-13 can stimulate PMN and modulates the inflammatory reactions via the cyclooxygenase pathway.

Cells, Cultured↗

The effect of human polyclonal anti-dsDNA autoantibodies on apoptotic gene expression in cultured rat glomerular mesangial cells.

In our previous studies, we found that polyclonal anti-double-stranded DNA antibodies (anti-dsDNA) purified from sera of patients with active systemic lupus erythematosus (SLE) were cytotoxic to cultured rat glomerular mesangial cells (RMC) through an apoptotic mechanism. In order to determine whether these nephritogenic antibodies affect the expression of apoptosis-related genes in the tissues, the expression of Fas, p53, c-myc, and bcl-2 genes in the kidneys and livers of 12-week-old normal BALB/c and autoimmune MRL-lpr/lpr mice was detected by a reverse transcription-assisted polymerase chain reaction (RT-PCR). We found the mRNA of the four genes were expressed in the tissues of the normal mice. In contrast, decreased expression of the four genes in the kidney and absent expression of bcl-2 in the liver of the lpr mice were noted. Interestingly, RMC only expressed p53 and c-myc, but not Fas or bcl-2, in culture. The purified polyclonal anti-dsDNA dose-responsively (50-200 IU/ml) suppressed the 3H-thymidine incorporation of RMC after incubation for 48 h. However, the incubation of 100 IU/ml of anti-dsDNA with RMC for 4 h did not affect the expression of these apoptotic genes. The results suggest that anti-dsDNA induce RMC apoptosis via an unidentified mechanism different from Fas, c-myc or p53 pathway.

Animals↗

Dieting behavior of Asian college women attending a US university.

Dieting behavior, body dissatisfaction, self-esteem, and food intake of 73 Asian women attending a US university were investigated and compared retrospectively with attitudes of 247 US-born female students at the same university. The Asian women reported restrained eating and body dissatisfaction only about half as often as the US women did. In both the Asian and US college women, body dissatisfaction scores were significantly correlated to body mass index and self-esteem scores. Fourteen percent of the Asian women in the restrained eating/body dissatisfied group, and 40% of the US students in that group reported intentional vomiting for weight control. Some of the Asian international students practiced undesirable dieting behaviors and reported body dissatisfaction levels similar to those of many US college women. College health professionals should recognize that disordered eating among Asian women must not be overlooked because of stereotypical perceptions about Asian women's body size and type.

Adolescent↗