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Biomedical subjects

C T Chou

Publications and source records attributed to C T Chou.

At least 19 recordsLinked to original sources
PubMed2006

Bilateral retrocaval ureters with IVC duplication.

We report a rare case of bilateral retrocaval ureters associated with duplicated inferior renal cava. A 69-year-old woman was sent to our emergency room for abdominal pain. Multidetector computed tomogram with multiplanar reconstruction revealed duplicated inferior renal cavae and the bilateral ureters were positioned behind the duplicated inferior vena cava. To our knowledge, coexistence of bilateral retrocaval ureters and duplicated inferior renal cavae has not been reported in the literature.

Aged↗
PubMed2006

Safrole-induced Ca2+ mobilization and cytotoxicity in human PC3 prostate cancer cells.

The effect of the carcinogen safrole on intracellular Ca2+ mobilization and on viability of human PC3 prostate cancer cells was examined. Cytosolic free Ca2+ levels ([Ca2+]i) were measured by using fura-2 as a probe. Safrole at concentrations above 10 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 350 microM. The Ca2+ signal was reduced by more than half after removing extracellular Ca2+ but was unaffected by nifedipine, nicardipine, nimodipine, diltiazem, or verapamil. In Ca2+-free medium, after treatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release Ca2+. Neither inhibition of phospholipase C with U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 0.65-65 microM safrole did not affect cell viability, but incubation with 325-625 microM safrole decreased viability. Collectively, the data suggest that in PC3 cells, safrole induced a [Ca2+]i increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx. Safrole can decrease cell viability in a concentration-dependent manner.

Calcium Channel Blockers↗
PubMed2006

Psoriasis vulgaris in Chinese individuals is associated with PSORS1C3 and CDSN genes.

BACKGROUND: Besides the HLA-Cw*0602 allele, the psoriasis susceptibility 1 candidate 3 (PSORS1C3) and corneodesmosin (CDSN) genes are two probable psoriasis susceptibility genes in the PSORS1 locus. The -79C, -26C and +246A alleles of the PSORS1C3 gene, the CDSN*971T allele, CDSN*TTC (619T-1236T-1243C) and CDSN*5 (619T-1240G-1243C) are strongly associated with psoriasis in the caucasian population. Until now, no haplotype study of the PSORS1C3 and CDSN genes has been documented in Chinese patients with psoriasis vulgaris. OBJECTIVES: We aimed to determine whether genetic polymorphisms of the PSORS1C3 and CDSN genes were associated with an increased risk of psoriasis vulgaris in Chinese patients in Taiwan. METHODS: We investigated the PSORS1C3 and CDSN genes for disease association by direct sequencing in 178 patients with psoriasis vulgaris and 203 control subjects. Genotyping for HLA-Cw*0602, alpha-helix coiled-coil rod homologue (HCR) gene and single nucleotide polymorphism (SNP) n.9 was also carried out using a sequence-based typing method. RESULTS: The PSORS1C3*582A allele, an SNP in the 3'-untranslated region of the PSORS1C3 gene, was a major psoriasis vulgaris susceptibility allele in the Chinese population, and the association was much stronger in patients with early-onset psoriasis vulgaris (22.3% vs. 6.9%, odds ratio = 3.87, P(c) =0.0000072). The frequencies of CDSN*TTC and CDSN*971T were also significantly increased in patients with early-onset psoriasis vulgaris. Moreover, PSORS1C3*582A, SNP n.9*C, Cw*0602 and HCR*WWCC were in near complete linkage disequilibrium (LD) with each other; in contrast, the LD with the CDSN gene was not so strong. SNP n.9*C-Cw*0602-PSORS1C3*582A-HCR*WWCC was a major susceptibility haplotype in patients with early-onset psoriasis vulgaris (P < 10(-7)) and this risk haplotype also carried CDSN*TTC and CDSN*971T. CONCLUSIONS: The PSORS1C3 and CDSN genes are important psoriasis susceptibility genes in Chinese patients with psoriasis vulgaris.

Adolescent↗
PubMed2006

Effect of riluzole on Ca2+ movement and cytotoxicity in Madin-Darby canine kidney cells.

Riluzole is a drug used in the treatment of amyotrophic lateral sclerosis; however, its in vitro action is unclear. In this study, the effect of riluzole on intracellular Ca2+ concentration ([Ca2+]i) in Madin-Darby canine kidney (MDCK) cells was investigated using the Ca2+ -sensitive fluorescent dye, fura-2. Riluzole (100-500 microM) caused a rapid and sustained increase of [Ca2+]i in a concentration-dependent manner (EC50 = 150 microM). Some 40 and 50% of this [Ca2+]i increase was prevented by the removal of extracellular Ca2+ and the addition of La3+, respectively, but was unchanged by dihydropyridines, verapamil and diltiazem. In Ca2+ -free medium, thapsigargin - an inhibitor of the endoplasmic reticulum (ER) Caz+ -ATPase--caused a monophasic [Ca2+]i increase, after which the increasing effect of riluzole on [Ca2+]i was attenuated by 70%; in addition, pre-treatment with riluzole abolished thapsigargin-induced [Ca2+]i increases. U73122, an inhibitor of phospholipase C (PLC), abolished ATP (but not riluzole)-induced [Ca2+]i increases. At concentrations of 250 and 500 microM, riluzole killed 40 and 95% cells, respectively. The cytotoxic effect of riluzole (250 microM) was unaltered by pre-chelating cytosolic Ca2+ with BAPTA. Collectively, in MDCK cells, riluzole rapidly increased [Ca2+]i by stimulating extracellular Ca2+ influx via an La3+ -sensitive pathway and intracellular Ca2+ release from the ER via, as yet, unidentified mechanisms. Furthermore, riluzole caused Ca2+ -unrelated cytotoxicity in a concentration-dependent manner.

Animals↗
PubMed2005

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↗
PubMed2005

Study of undifferentiated spondyloarthropathy among first-degree relatives of ankylosing spondylitis probands.

OBJECTIVE: To estimate in a Chinese population the prevalence of undifferentiated spondyloarthropathy (USpA) among first-degree relatives (FDRs) of ankylosing spondylitis (AS) probands, and to compare the clinical features of familial USpA with those of sporadic USpA. METHODS: The FDRs of two separate cohorts of consecutive AS probands were evaluated for the prevalence of USpA, using the Modified New York criteria and the European Spondylitis Study Group criteria for AS and SpA, respectively. Sporadic USpA and FDRs of non-SpA rheumatic patient probands served as separate controls. RESULTS: Among the 301 FDRs of 102 AS probands, 7.0% were USpA. This was 1000 times higher than the 147 FDRs of 40 non-SpA probands (P = 0.00230). Within the AS families, USpA was less male-dominated than AS (33.3 vs 72.5%) (P = 0.006). The only feature distinguishing familial from sporadic USpA was that the percentages of HLA B27 were 100 and 50%, respectively (P<0.001). CONCLUSION: USpA and AS coexist in the same Chinese families, both being predisposed by HLA B27. In these families, a female gender favours the development of USpA rather than AS. A significant subset of sporadic USpA (HLA B27-negative group) has a different genetic predisposition compared with familial USpA.

Adult↗
PubMed2005

Effect of celecoxib on Ca2+ fluxes and proliferation in MDCK renal tubular cells.

The effect of celecoxib on renal tubular cells is largely unexplored. In Madin Darby canine kidney (MDCK) cells, the effect of celecoxib on intracellular CaCa2+ concentration ([Ca2+]i) and proliferation was examined by using the Ca(2 +)-sensitive fluorescent dye fura-2 and the viability detecting fluorescent dye tetrazolium, respectively. Celecoxib (> or =1 micro M) caused an increase of [CaCa2+]i in a concentration-dependent manner. Celecoxib-induced [CaCa2+]i increase was partly reduced by removal of extracellular CaCa2+. Celecoxib-induced CaCa2+ influx was independently suggested by MnCa2+ influx-induced fura-2 fluorescence quench. In Ca(2 +)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2 +)-ATPase, caused a monophasic [CaCa2+]i increase, after which celecoxib only induced a tiny [CaCa2+]i increase; conversely, pretreatment with celecoxib completely inhibited thapsigargin-induced [CaCa2+]i increases. U73122, an inhibitor of phospholipase C, abolished ATP (but not celecoxib)-induced [CaCa2+]i increases. Overnight incubation with 1 or 10 micro M celecoxib decreased cell viability by 80% and 100%, respectively. These data indicate that celecoxib evokes a [CaCa2+]i increase in renal tubular cells by stimulating both extracellular CaCa2+ influx and intracellular CaCa2+ release and is highly toxic to renal tubular cells in vitro.

Animals↗
PubMed2005

Econazole induces increases in free intracellular Ca2+ concentrations in human osteosarcoma cells.

Econazole is an antifungal drug with different in vitro effects. However, econazole's effect on osteoblast-like cells is unknown. In human MG63 osteosarcoma cells, the effect of econazole on intracellular Ca2+ concentrations ([Ca2+]i) was explored by using fura-2. At a concentration of 0.1 microM, econazole started to cause a rise in [Ca2+]i in a concentration-dependent manner. Econazole-induced [Ca2+]i rise was reduced by 74% by removal of extracellular Ca2+. The econazole-induced Ca2+ influx was mediated via a nimodipine-sensitive pathway. In Ca2+ -free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca+ -ATPase, caused a [Ca2+]i rise, after which the increasing effect of econazole on [Ca2+]i was abolished. Pretreatment of cells with econazole to deplete Ca2+ stores totally prevented thapsigargin from releasing Ca2+. U73122, an inhibitor of phospholipase C, abolished histamine (an inositol 1,4,5-trisphosphate-dependent Ca2+ mobilizer)-induced, but not econazole-induced, [Ca2+]i rise. Econazole inhibited 76% of thapsigargin-induced store-operated Ca2+ entry. These findings suggest that in MG63 osteosarcoma cells, econazole increases [Ca2+]i by stimulating Ca2+ influx and Ca2+ release from the endoplasmic reticulum via a phospholipase C-independent manner. In contrast, econazole acts as a potent blocker of store-operated Ca2+ entry.

Antifungal Agents↗
PubMed2004

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↗
PubMed2002

Changes in the clinical and laboratory features of lupus patients after the big earthquake in Taiwan.

In order to understand the impact of the massive earthquake on disease activity, 60 patients with systemic lupus erythematosus (SLE) living in the earthquake area (group 1) and 31 patients living away from the area (group 2) were enrolled in this study. A questionnaire was used to record demographic data and clinical manifestations before and 6 months after the earthquake. Laboratory tests, including serum C3, C4, creatinine, anti-DNA antibody, CBC and 24 h urine protein were taken. The results showed that nine patients in group 1 had obvious disease flare-up as evidenced by fever, arthralgia, malar rash and photosensitivity, increased protein loss or edema, and other symptoms. However, there were no significant changes in either group 1 or 2 patients. In contrast, the comparison of laboratory parameters in group 1 patients before and after the earthquake showed a significant decrease of C4 from 17.3 +/- 15.3 to 14.1 +/- 7.33 and a significant increase of creatinine from 1.20 +/- 1.54 to 1.27 +/- 1.70 (P < 0.05), respectively. No significant difference for either C4 or creatinine was found in group 2 patients. In conclusion, there was no striking change in the clinical aspects for lupus patients. However, some laboratory results became abnormal in group 1 patients after the earthquake, indicating that their lupus status may have worsened.

Adult↗
PubMed2002

A double-blind, randomized, controlled parallel group study evaluating the efficacy and safety of acemetacin for the management of osteoarthritis.

The aim of the present study was to compare the efficacy and tolerability of a new form of nonsteroidal antiinflammatory drug (NSAID), acematacin (Acemet), with indomethacin, in patients suffering from osteoarthritis (OA). Patients diagnosed with OA were included in a double-blind, randomized, controlled parallel group study A total of 42 patients were randomized to either acemetacin 60 mg t.i.d. or indomethacin 25 mg t.i.d. for 28 days. At an outpatient clinic, each patient was followed up regularly for efficacy, compliance and possible adverse events. Both drugs produced a statistically significant improvement for primary efficacy variables: change of pain score during motion and restriction of body movement. Values for overall tolerability and incidence of gastrointestinal side effects were significantly lower for acemetacin than for indomethacin. We therefore suggest that acemetacin, by demonstrating significant tolerability and safety advantages, is as effective as indomethacin for the treatment of OA.

Aged↗
PubMed2001

The detection of the HLA-B27 antigen by immunomagnetic separation and enzyme-linked immunosorbent assay-comparison with a flow cytometric procedure.

The HLA-B27 antigen is an important genetic marker in ankylosing spondylitis (AS). Methods for the detection of B27 include the microlymphocytotoxicity test and, more recently, flowcytometry (FC). Here, we describe a new method, IMS-ELISA, for measuring the B27-antigen. It combines immunomagnetic separation (IMS), to obtain B27-positive cells from whole blood samples, with an enzyme-linked immunosorbent assay (ELISA) as a read-out. IMS-ELISA was tested on 367 samples obtained from five different hospitals in Taiwan. The sensitivity, specificity and accuracy of the method were compared with FC. Any conflicting data between IMS-ELISA and FC was confirmed by HLA-DNA typing via PCR-SSP (polymerase chain reaction-sequence specific primers). Overall, the results for sensitivity, specificity and accuracy obtained by IMS-ELISA and FC did not show any significant difference (p>0.05). However, when considering laboratory time, cost, ease of operation and the screening of large samples for HLA-B27, the IMS-ELISA was superior to the FC method. We conclude that IMS-ELISA may be used as a fast screening method for HLA B27 detection.

Enzyme-Linked Immunosorbent Assay↗
PubMed2001

Apoptosis in rheumatoid arthritis--expression of Fas, Fas-L, p53, and Bcl-2 in rheumatoid synovial tissues.

Recent studies have suggested that apoptosis is one of the pathogenetic mechanisms in rheumatoid arthritis (RA). In this study, by using single and double immunohistochemical staining assays, Fas, Fas-L, p53, and Bcl-2 were measured simultaneously in RA and osteoarthritic (OA) and post-traumatic (PT) synovial tissues (ST) in order to understand the distribution of these apoptosis-related proteins. The TdT-mediated dUTP-biotin nick end labelling (TUNEL) method was performed to detect apoptotic cells. There was a significant increase of Fas, Fas-L, and p53 in RA ST, compared with OA or PT, but no significant difference of Bcl-2 expression was detected between patient groups. In RA ST, expression of Fas and p53 was detected in sub-lining layers and the majority of Fas- and p53-expressing cells were fibroblast-like synoviocytes. A positive correlation between Fas and p53 was demonstrated in RA ST. In RA ST, one-third of Fas-positive and 80% of p53-positive cells were also TUNEL-positive. These results indicate that apoptosis in RA is strongly associated with the expression of Fas and p53, but not Bcl-2.

Adult↗
PubMed2001

Spondyloarthropathies in eastern Asia.

The association between HLA-B27 and the spondyloarthropathies (SpAs) is so strong that it is supposed that the HLA-B27 molecule plays a pathogenetic role. In whites and Indonesians, the frequency of HLA-B27 is about 10%; in Chinese it is about 8%; and in Japanese it is only about 1%. The prevalence of SpA in the Chinese is at least 0.2%, but in native Indonesians, Philippinos, and Malaysians, SpA is rarely seen. Twenty-three subtypes (B*2701-B*2723) have been distinguished. These subtypes are not equally distributed over the world. In most countries the distribution of the subtypes among HLA-B27 SpA patients is the same as that among the normal HLA-B27-positive population. In China, the subtype B*2704 is frequent and the prevalence of SpA is high. Native Indonesians, however, mostly have subtype B*2706, and SpA is rarely seen in this population. It was shown that B*2706, probably like B*2709 in Sardinia, is not associated with SpA. The difference between the SpA-associated and non-SpA-associated subtypes is limited to only two amino acid residues (114 and 116) at the bottom of the peptide-binding groove of HLA-B27. This small difference between health and disease rewards studies for different peptide-binding capacities and may help us characterize the peptides that are involved in the pathogenesis of SpA. The differences in disease associations in these countries also have clinical implications. In Southeast Asia, HLA-B27 typing without subtyping has less clinical usefulness than in parts of the world where B*2706 is rarely seen. When native Indonesians, Malaysians, or Philippinos are suspected of having ankylosing spondylitis or a related SpA, it is worth asking if they had white or Chinese ancestors. If native HLA-B27-positive Indonesians (with subtypes other than B*2706) develop SpA, the clinical features are not different from those in other parts of the world. In the Chinese population on the mainland and in Taiwan, juvenile SpA is frequently seen. The onset is often a peripheral arthritis or enthesitis.

Asian People↗
PubMed2001

Vertebral bone marrow perfusion evaluated with dynamic contrast-enhanced MR imaging: significance of aging and sex.

PURPOSE: To investigate blood perfusion of nonfractured, normal-appearing vertebral bodies with regard to age and sex. MATERIALS AND METHODS: Dynamic magnetic resonance imaging (160 images obtained in 80 seconds) was performed from T10 to L5 in 66 patients. Patients were assigned to three groups: group 1, those 50 years or younger without compression fracture; group 2, those older than 50 years without compression fracture; or group 3, those older than 50 years with compression fracture. Peak enhancement percentage and enhancement slope were determined from the time-intensity curve of normal (nonfractured) vertebral body. Comparisons were made between groups, and the effect of age and sex interaction was analyzed. RESULTS: Higher peak enhancement percentage was demonstrated for group 1 compared with group 2 (58.21 +/- 44.65 [SD] vs 21.88 +/- 14.77, P <.005). Group 1 women revealed a higher enhancement percentage compared with group 1 men (87.17 +/- 54.13 vs 38.16 +/- 21.69, P <.05), which significantly decreased in those older than 50 years (from 87.17 +/- 54.13 to 17.98 +/- 13.80, P <.005). For men, this decrease in those older than 50 years was not as pronounced (from 38.16 +/- 21.69 to 25.38 +/- 15.43, P >.05). Presence of compression fracture at other levels of the spine (group 3) was not associated with a different enhancement percentage for normal vertebrae. CONCLUSION: Rate of vertebral bone marrow perfusion revealed a significant decrease in subjects older than 50 years. Women demonstrated a higher marrow perfusion rate than men younger than 50 years and a more marked decrease than men older than 50 years.

Adult↗
PubMed2001

Evaluation of acupuncture effect to chronic myofascial pain syndrome in the cervical and upper back regions by the concept of Meridians.

Myofascial pain syndrome (MPS) in the cervical and upper back regions is a common medical problem. The involved muscles include trapezius, multifidi, splenius cervicis, levator scapulae, supraspinatus or infraspinatus. Acupuncture is a well-known method for relief of chronic pain. In this study, we evaluated the effect of acupuncture in MPS and its durability by using the concept of meridians. Twenty-nine patients with chronic MPS in the upper back and cervical regions received acupuncture 2 times per week for 3 weeks. According to the pathways of the meridians, we chose acupuncture points by the pain regions located in which parts of meridian passing (i.e. "Where the meridian passes, where to treat the disease."). We evaluated the intensity of pain by visual analog scales (VAS) and active range of motion (ROM) of neck before and after therapy. After receiving acupuncture for 3 weeks, VAS of pain fell significantly from 9.0+/-1.0 to 4.9+/-2.5 and active ROM of neck significantly increased from 35.8+/-10.2 degrees to 61.3+/-9.4 degrees (p<0.05). The onset of symptom relief was gradual and duration of symptom relief after a course of acupuncture was average 5.3+/-1.2 days. In conclusion, acupuncture is a somewhat effective method for pain relief of patients with chronic MPS in the cervical and upper back regions. However, the effect of acupuncture with the concept of meridians on MPS is insidious and the duration of the relief is not long enough.

Acupuncture↗