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Chen WM, Chen TH, Huang CK, Chiang CC, Lo WH. Treatment of malignant bone tumours by extracorporeally irradiated autograft-prosthetic composite arthroplasty. THE JOURNAL OF BONE AND JOINT SURGERY. BRITISH VOLUME 2002; 84:1156-61. [PMID: 12463662 DOI: 10.1302/0301-620x.84b8.13508] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Autogenous bone graft which has been either autoclaved or irradiated is commonly used in oriental countries as an alternative to allograft. We started to use the technique of extracorporeal irradiation of the resected specimen and reimplantation (ECIR) in 1991. There was, however, a high incidence of fracture of the irradiated bone and loss of articular cartilage. In an attempt to reduce these complications, we combined the irradiated autograft with a conventional arthroplasty. Between 1995 and 1998, 14 patients underwent limb salvage by this method. Seven had an osteosarcoma, two bony metastases, three a chondrosarcoma, one a malignant fibrous histiocytoma, and one a leiomyosarcoma. Ten tumours were located in the proximal femur, two in the proximal humerus, and two in the distal femur. One patient who had a solitary metastasis in the proximal part of the left femur died from lung metastases 13 months after operation. The remaining 13 patients were alive and without evidence of local recurrence or distant metastases at a mean follow-up of 43 months (28 to 72). Postoperative palsy of the sciatic nerve occurred in one patient, but no complications such as wound infection, fracture, or nonunion were seen. All host-irradiated bone junctions healed uneventfully within eight months. Using the Enneking functional evaluation system, the mean postoperative score for all 14 patients was 80% (57 to 93). The use of irradiated autograft prosthesis composites reduces the complications of ECIR and gives good functional results. It may be a good alternative in limb-salvage surgery, especially in countries where it is difficult to obtain allografts.
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Yeh KS, Chen TH, Liao CW, Chang CS, Lo HC. PCR amplification of the Salmonella typhimurium fimY gene sequence to detect the Salmonella species. Int J Food Microbiol 2002; 78:227-34. [PMID: 12227641 DOI: 10.1016/s0168-1605(02)00115-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This study evaluated the suitability of fimY gene amplification by PCR as an effective means of detecting Salmonella species. Although fimY gene of Salmonella typhimurium is involved in regulating type 1 fimbrial expression, the amino acid sequence of FimY shares very little homology with other known prokaryotic proteins in the GenBank database. Therefore, fimY is a promising target gene to detect the presence of Salmonella species. Herein, two primers internal to the fimY gene of S. typhimurium are used to investigate the distribution of the fimY homologous sequence among 45 Salmonella serovars and 20 non-Salmonella species by using PCR. Experimental results indicated that only Salmonella species possessed the fimY homologous sequence, subsequently generating the specific 526-bp DNA fragments. The sensitivity of the fmY-specific primer set was demonstrated on a Salmonella-free swab sample from a pork carcass surface, which was then artificially contaminated with different concentrations of S. typhimurium. A combining of pre-enrichment step in buffered peptone water and PCR amplification of fimY allowed the detection of S. typhimurium at the concentration of 3.4 x 10(0) CFU/ml from the swab sample. With an additional enrichment step in Rappaport-Vassiliadis (RV) broth, this procedure can also detect pork carcass surface naturally contaminated with Salmonella species in a slaughterhouse. Results in this study demonstrate that fimY is unique to Salmonella species and is an appropriate PCR target for detecting these microorganisms.
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Chen YS, Yao CH, Chen TH, Lin JG, Hsieh CL, Lin CC, Lao CJ, Tsai CC. Effect of acupuncture stimulation on peripheral nerve regeneration using silicone rubber chambers. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2002; 29:377-85. [PMID: 11789580 DOI: 10.1142/s0192415x01000393] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The purpose of this study was to determine whether acupuncture could affect the regeneration of a 10-mm gap of rat sciatic nerve created between the proximal and distal nerve stumps, which were sutured into silicone rubber tubes. Empty silicone rubber tubes with no further treatment were used as controls. Six weeks after implantation, the animals received the acupuncture or the electroneedling treatment exhibited a more mature ultrastructural nerve organization with significantly higher numbers in the axon density, the blood vessel area, and the percentage of blood vessel area occupied in total nerve area than the controls. In addition, the electroneedling could combine both the needling and the electrical stimulation to potentiate the nerve-growth promoting effect of the acupuncture treatment. These results showed that acupuncture treatment could elicit positive effects on regenerated peripheral nerves.
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Palafox NA, Ou AC, Haberle H, Chen TH. Quantifying tobacco related health care expenditures in the Republic of the Marshall Islands: a case study in determining health costs in a developing US associated island nation. ASIAN AMERICAN AND PACIFIC ISLANDER JOURNAL OF HEALTH 2002; 9:74-80. [PMID: 11720417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
OBJECTIVES This case study examines the advantages, disadvantages, and utility of three research methods to measure the medical costs of tobacco use in the Republic of the Marshall Islands (RMI). METHODS The authors used the morbidity-based models, models based on the difference in utilization of medical facilities between smokers and non-smokers, and models of inter-country comparisons. FINDINGS In the RMI, morbidity models would have a propensity to grossly under-estimate the medical costs of tobacco use. Models that measure the difference in medical service utilization between smokers and non-smokers can be confounded by cultural factors and by the level of health care that is provided. The RMI population structure affected the sampling methods. The external validity of the survey instrument may be increased through measuring more parameters with greater precision. Inter-country comparisons may be used to approximate and set upper and lower limits of costs for past medical costs, and may be the only method to determine future health care costs from tobacco use. CONCLUSIONS Determining medical costs of tobacco use in an US Associated island nation with an under-developed health care infrastructure has not been previously attempted. There were significant methodological challenges that were encountered. Health, economic, cultural, and research environments in the RMI are unique and require innovative methods to determine medical costs associated with tobacco use. Direct application of the methodologies utilized in the United States to determine medical costs of tobacco use may grossly under-estimate the medical cost of tobacco use in the RMI. The research challenges can be addressed.
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Chen YS, Hu CL, Hsieh CL, Lin JG, Tsai CC, Chen TH, Yao CH. Effects of percutaneous electrical stimulation on peripheral nerve regeneration using silicone rubber chambers. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2001; 57:541-9. [PMID: 11553884 DOI: 10.1002/1097-4636(20011215)57:4<541::aid-jbm1200>3.0.co;2-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The purpose of this study was to determine whether 0.8-1 mA, 2 Hz of percutaneous electrical stimulation could affect the regeneration of a 10-mm gap of rat sciatic nerve created between the proximal and distal nerve stumps, which were sutured into silicone rubber tubes. Six weeks after implantation, though the group receiving the electrical stimulation had a lower success percentage of regeneration (57%) compared with the controls receiving no stimulation (70%), quantitative histology of the successfully regenerated nerves revealed that the mean values of the axon density, blood vessel number, blood vessel area, and percentage of blood vessel area in total nerve area in the group with the electrical stimulation were all significantly larger than those in the controls (p < 0.05). These results showed that the electrical stimulation could elicit rehabilitating effects on the regenerated nerves.
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Chang W, Pratt S, Chen TH, Bourguignon L, Shoback D. Amino acids in the cytoplasmic C terminus of the parathyroid Ca2+-sensing receptor mediate efficient cell-surface expression and phospholipase C activation. J Biol Chem 2001; 276:44129-36. [PMID: 11535593 DOI: 10.1074/jbc.m104834200] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The C-terminal tail of the calcium receptor (CaR) regulates the affinity of the receptor for ligand, desensitization, and membrane localization. To determine the role of specific amino acids in the bovine parathyroid CaR in mediating signal transduction and cell-surface expression, we transfected truncated and mutated CaR cDNAs into HEK-293 cells. The ability of high extracellular [Ca(2+)] ([Ca(2+)](o)) to increase total inositol phosphate (InsP) production, an index of phospholipase C (PLC) activation, was determined. Receptor expression was assessed by immunoblotting and immunocytochemistry. In cells transiently or stably expressing receptors with the C-terminal tail truncated after residue 895 (CaR-(1-895)) or 929 (CaR-(1-929)), raising [Ca(2+)](o) increased InsPs to levels comparable with those of cells expressing wild-type CaRs. There were no PLC responses to high [Ca(2+)](o) (up to 30 mm) in cells expressing CaRs with C-terminal tails of only 3 residues (CaR-(1-866)), even though these receptors were expressed in the membrane. We scanned the residues between Ser(866) and Val(895) using tandem-Ala and single-site mutagenesis. Two point mutants (His(880) --> Ala and Phe(882) --> Ala CaR) showed 50-70% reductions in high [Ca(2+)](o)-induced InsP production. The levels of expression and glycosylation of these mutants were comparable with wild-type CaRs, but both receptors were profoundly retained in intracellular organelles and co-localized with the endoplasmic reticulum marker BiP. This suggested that the signaling defects of these receptors were likely because of defective trafficking of receptors to the cell surface. Modeling of the C-terminal domain of the CaR indicated that His(880) and Phe(882) are situated in a putative alpha-helical structure of 15 amino acids between residues 877 and 891 in the C-terminal tail. Our studies support the idea that specific amino acids, and possibly a unique secondary structure in the C-terminal tail, are required for the efficient targeting of the CaR to the cell surface required for PLC activation.
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Chen RC, Chang SF, Su CL, Chen TH, Yen MF, Wu HM, Chen ZY, Liou HH. Prevalence, incidence, and mortality of PD: a door-to-door survey in Ilan county, Taiwan. Neurology 2001; 57:1679-86. [PMID: 11706111 DOI: 10.1212/wnl.57.9.1679] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The reported prevalence and incidence rates of PD were significantly lower in China than those in Western countries. People in China and Taiwan have a similar ethnic background. OBJECTIVE To investigate the prevalence, incidence, and mortality rate of PD in Taiwan. METHOD The authors conducted a population-based survey using a two-stage door-to-door approach for patients aged 40 years or older in Ilan, Taiwan. Patients were diagnosed with PD by having at least two of the four cardinal signs of parkinsonism and exclusion of seconddary parkinsonism. To identify new cases of PD after the survey, patients with negative results of parkinsonism in the first stage were matched to the information on clinical diagnosis of PD from the Bureau of National Health Insurance toward the end of December 31, 1997. All cases of PD were linked to the Taiwan mortality registration to ascertain causes of deaths until December 31, 1999. RESULTS The participation rate was 88.1% among the 11,411 contacted individuals. Thirty-seven cases of PD were identified. The age-adjusted prevalence rate of PD for all age groups was 130.1 per 100,000 population after being adjusted to the 1970 US census, assuming no cases of PD would be found among those younger than 40 years of age. Of 9972 non-PD subjects in the first screen, 15 new cases of PD were ascertained. The age-adjusted incidence rate was 10.4 per 100,000 population for all age groups. The case fatality rate of PD after a 7-year follow-up was 40.4% (21 deaths in 52 patients with PD). The relative risk of death for PD cases versus non-PD cases was 3.38 (95% CI: 2.05-4.34). The 5-year cumulative survival rate in PD cases (78.85%) was statistically lower than that in non-PD cases (92.84%). CONCLUSION The prevalence and incidence rates of PD in Taiwan were much higher than those reported in China, but closer to those in Western countries. These results suggest that environmental factors may be more important than racial factors in the pathogenesis of PD.
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Chen TH, Yen MF, Tung TH. A computer simulation model for cost-effectiveness analysis of mass screening for Type 2 diabetes mellitus. Diabetes Res Clin Pract 2001; 54 Suppl 1:S37-42. [PMID: 11580967 DOI: 10.1016/s0168-8227(01)00307-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The cost-effectiveness analysis of mass screening for Type 2 diabetes mellitus (DM) was performed to elucidate whether, who and how often it should be conducted in Taiwan. A series of Markov process was developed to model the disease natural history of Type 2 DM. A hypothetical cohort with 30,000 residents aged over 30 years in Taiwan was randomly assigned to three arms of screening regimes, biennial, five-yearly and the control group. A Monte Carlo computer simulation was performed to calculate effectiveness of two screening regimes compared with the control group. Direct costs and utilities were incorporated to each corresponding state to calculate the incremental costs per life-years gained and per quality-adjusted life-years (QALYs) for biennial and five-yearly screening regimes. The incremental costs for biennial screening regime were estimated at $26,750 per life-year gained, and $17,833 per QALY. The corresponding figures for five-yearly screening regime were $10,531 per life-year gained and $17,113 per QALY. The incremental costs per life-year gained and per QALY increase with age, ranging from $17,238 for aged 30-39 years to $54,700 for aged over 70 years and from $9193 to 36,467, respectively. In conclusion, mass screening for Type 2 DM, especially in younger subjects, with 5-year inter-screening interval is cost-effective in Taiwan.
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Liou HH, Oon PC, Lin HC, Wang PJ, Chen TH. Risk factors associated with infantile spasms: a hospital-based case-control study in Taiwan. Epilepsy Res 2001; 47:91-8. [PMID: 11673024 DOI: 10.1016/s0920-1211(01)00304-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We investigated the risk factors associated with infantile spasms (IS) by a hospital-based case-control study in Taiwan. Twenty-five patients with IS were recruited from one medical center (National Taiwan University Hospital) between 1990 and 1997. Based on a close-structured questionnaire, standardized interviews were carried out to obtain information on risk factors associated with IS. Two comparison groups are used, including a total of 106 subjects in the Disease Control group, and 139 subjects in the Normal Control group. Unconditional logistic regression is used to calculate odds ratios (OR) and 95% confidence interval (CI). Univariate analysis revealed gestational age, congenital cerebral anomalies, tuberous sclerosis (TS), asphyxia, febrile seizure, and developmental delay (before onset of spasm) were at increased risk of IS. After adjustment of multiple risk factors through unconditional logistic regression, significant risk factors for IS include congenital cerebral anomalies, TS, asphyxia, postterm, and developmental delay were highly associated with IS. The risk factors of IS may closely relate to underlying neurological abnormalities. Our results are consistent with the previous findings.
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Lin CC, Chen TH, Ho WC, Chen TY. Endoscopic treatment of a Cameron lesion presenting as life-threatening gastrointestinal hemorrhage. J Clin Gastroenterol 2001; 33:423-4. [PMID: 11606864 DOI: 10.1097/00004836-200111000-00018] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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Lin CP, Chen YP, Chen TH, Liu WH, Lin FS, Wang MJ. Anomalous origin of the left main coronary artery from the main pulmonary artery in a young adult. Circulation 2001; 104:1575-6. [PMID: 11571255 DOI: 10.1161/hc3801.095695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Chen TH, Chan KC, Cheng YJ, Wang MJ, Tsai SK. Bedside pericardiocentesis under the guidance of transesophageal echocardiography in a 13-month-old boy. J Formos Med Assoc 2001; 100:620-2. [PMID: 11695278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
Pericardial effusion is a common sequel to cardiac surgery. Urgent pericardiocentesis is required in the case of cardiac tamponade. In adult patients, most pericardiocentesis is accomplished using transthoracic echocardiographic imaging. However, transthoracic echocardiographic imaging may interfere with the procedure field in children. We report the case of a 13-month-old boy who developed cardiac tamponade resulting in heart failure after surgical repair of tetralogy of Fallot. Urgent pericardiocentesis was safely performed at the bedside under transesophageal echocardiographic guidance. Transesophageal echocardiographic monitoring during pericardiocentesis in children has the advantages of better imaging of pericardial effusion without procedure-field interference.
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Chang JJ, Chen TH, Chan P, Chen YJ, Hsu FL, Lo MY, Lin JY. The in vitro inhibitory effect of tannin derivatives on 3-hydroxy-3-methylglutaryl-coenzyme a reductase on vero cells. Pharmacology 2001; 62:224-8. [PMID: 11359999 DOI: 10.1159/000056099] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Coronary heart disease is still the major cause of death in industrialized countries. Multiple primary or secondary interventional trials to lower serum cholesterol in humans have resulted in significant reduction of coronary events and death, one of the major reasons attributed to developing a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor such as pravastatin. Developing new inhibitors of cholesterol synthesis is still common in the pharmaceutical industry. Tannin comprises a large group of natural polyphenolic compounds possessing antioxidant effects. The methods for analysis of specific inhibitors of mevalonate biosynthesis have already been well established by using Vero cells, a cell line obtained from kidneys of African green monkeys. Tannin derivatives isolated from different traditional Chinese herbs were dissolved in DMSO and incubated with Vero cells with or without the addition of 1 mmol/l mevalonate or 5 mmol/l sodium acetate for 24 h in order to observe cell growth. Pravastatin, a specific HMG-CoA reductase inhibitor, was used as positive control which could inhibit Vero cells growth effectively and cell growth inhibition was reversible after adding 1 mmol/l mevalonate. More than 50 tannin derivatives were used for the study, but only two compounds - proanthrocyanidin A-2 (belonging to the flavan-3-ol group) and 1,2,3,6-tetra-O-galloyl-beta-D-glucose (belonging to the gallotannin group) - showed significant growth inhibition of Vero cells. This study showed that some isolated tannin derivatives from traditional herbs were effective HMG-CoA reductase inhibitors which might be developed into new hypocholesterolemic agents.
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Chen TH, Liu JC, Chang JJ, Tsai MF, Hsieh MH, Chan P. The in vitro inhibitory effect of flavonoid astilbin on 3-hydroxy-3-methylglutaryl coenzyme A reductase on Vero cells. ZHONGHUA YI XUE ZA ZHI = CHINESE MEDICAL JOURNAL; FREE CHINA ED 2001; 64:382-7. [PMID: 11584575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
BACKGROUND Epidemiological studies have shown that hypercholesterolemia is a major risk factor for coronary heart disease. In clinical trials of lipid lowering therapy, 3-hydroxy-3-methylglutaryl Coenzyme A (HMG-CoA) reductase inhibitor has been shown to decrease cardiac events and mortality. Flavonoids are polyphenolic natural antioxidants existing in vegetables, fruits and beverages such as tea and wine. Previous studies have shown that some antioxidants had hypocholesterolemic effect, and flavonoid intake was associated with the decrease of mortality from coronary artery disease. The aim of this study was to evaluate the inhibitory effect of flavonoids on HMG-CoA reductase. METHODS The methods for analysis of specific inhibitors of mevalonate biosynthesis have been well-established, using Vero cells, a cell line obtained from kidneys of African green monkeys. Flavonoids isolated from different traditional Chinese herbs were dissolved in DMSO and incubated with Vero cells with or without the addition of 1 mM mevalonate or 5 mM sodium acetate in order to observe cell growth for 24 h. RESULTS Concentrations of 1 mM mevalonate or 5 mM sodium acetate were added into culture medium in order to observe the effect on cell growth. Different concentrations of pravastatin to inhibit cell growth were used as a positive control. About 40 flavonoid compounds were used for study, only one compound, astilbin (belonging to the flavonol group), showed significant inhibition of Vero cell growth. CONCLUSIONS This study shows that one flavonoid compound, isolated from traditional medicinal herbs, may be an effective HMG-CoA reductase inhibitor which might be developed into a new hypocholesterolemic agent.
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Chang W, Pratt SA, Chen TH, Tu CL, Mikala G, Schwartz A, Shoback D. Parathyroid cells express dihydropyridine-sensitive cation currents and L-type calcium channel subunits. Am J Physiol Endocrinol Metab 2001; 281:E180-9. [PMID: 11404236 DOI: 10.1152/ajpendo.2001.281.1.e180] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Parathyroid cells express Ca2+ -conducting currents that are activated by raising the extracellular Ca2+ concentration ([Ca2+]o). We investigated the sensitivity of these currents to dihydropyridines, the expression of voltage-dependent Ca(2+) channel (VDCC) subunits, and the effects of dihydropyridines on the intracellular free [Ca2+] ([Ca2+]i) and secretion in these cells. Dihydropyridine channel antagonists dose dependently suppressed Ca2+ -conducting currents, and agonists partially reversed the inhibitory effects of the antagonists in these cells. From a bovine parathyroid cDNA library, we isolated cDNA fragments encoding parts of an alpha(1S)- and a beta(3)-subunit of L-type Ca(2+) channels. The alpha(1S)-subunit cDNA from the parathyroid represents an alternatively spliced variant lacking exon 29 of the corresponding gene. Northern blot analysis and immunocytochemistry confirmed the presence of transcripts and proteins for alpha(1)- and beta(3)-subunits in the parathyroid gland. The addition of dihydropyridines had no significant effects on high [Ca2+]o-induced changes in [Ca2+]i and parathyroid hormone (PTH) release. Thus our studies indicate that parathyroid cells express alternatively spliced L-type Ca2+ channel subunits, which do not modulate acute intracellular Ca2+ responses or changes in PTH release.
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Chen TH, Tseng LM, Chau GY, Lui WY, Tsay SH, King KL, Loong CC, Hsia CY, Wu CW. Clinicopathologic and prognostic differences between patients with hepatitis B- and C-related resectable hepatocellular carcinoma. J Formos Med Assoc 2001; 100:443-8. [PMID: 11579608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
BACKGROUND AND PURPOSE Hepatitis B and C viral infections are important factors in the development of hepatocellular carcinoma (HCC). This study examined the clinicopathologic and prognostic differences in patients with hepatitis B- and C-related resectable HCC. METHODS A total of 270 HCC patients who underwent hepatic resection were enrolled. Among these patients, 211 were positive for hepatitis B surface antigen (HBsAg) and 59 were positive for anti-hepatitis C virus antibody (anti-HCV). The clinical manifestations, pathologic features, and treatment outcomes were compared between the HBsAg-positive and anti-HCV-positive groups. RESULTS Compared to anti-HCV-positive patients, HBsAg-positive patients were significantly younger, had a higher familial incidence of HCC, larger tumor size, and a higher incidence of multiple tumors. HCC patients who were anti-HCV positive had worse liver function and a higher incidence of history of blood transfusion. DNA flow cytometric analysis revealed significantly more proliferative activity in the non-tumor part of the liver in HBsAg-positive HCC patients. The 1-, 3-, and 5-year overall survival rates of HBsAg-positive patients were 79%, 57%, and 48%, respectively, and for anti-HCV-positive patients were 91%, 75%, and 62%, respectively. HBsAg-positive patients had a significantly lower overall survival rate than anti-HCV-positive patients (p = 0.018). CONCLUSIONS HBsAg-positive patients with resectable HCC had a less favorable survival rate after tumor resection than anti-HCV-positive HCC patients. This survival difference might have been related to the relatively advanced stage of disease and the higher proliferative activity of the non-tumor part of the liver in HBsAg-positive HCC patients.
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Chen TH, Hsu CS, Tsai PJ, Ho YF, Lin NS. Heterotrimeric G-protein and signal transduction in the nematode-trapping fungus Arthrobotrys dactyloides. PLANTA 2001; 212:858-863. [PMID: 11346962 DOI: 10.1007/s004250000451] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The fungus Arthrobotrys dactyloides produces specialized constricting rings to trap and then consume nematodes. The signal transduction pathway involved in the nematode-trapping process was examined. Mastoparan, an activator of G-protein, had a stimulatory effect on the inflation of ring cells, whereas a G-protein inhibitor, pertussis toxin, prevented ring-cell expansion. The 40-kDa G alpha of heterotrimeric G-proteins was specifically ADP-ribosylated by pertussis toxin. Using an antibody specific to the 35-kDa subunit G beta, we showed that immunogold-labeled G beta was more concentrated in ring cells than in the hyphae. In the absence of nematodes, the rings could be inflated by either pressurizing the culture in a syringe, raising intracellular Ca2+ concentrations, or adding warm water. We used these methods to reveal differences in responses to antagonists. The results support a model in which the pressure exerted by a nematode on the ring activates G-proteins in the ring cells. The activation leads to an increase in cytoplasmic Ca2+, activation of calmodulin, and finally the opening of water channels. The ring cells expand to constrict the ring and thus immobilize the nematode.
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Makita T, Hernandez-Hoyos G, Chen TH, Wu H, Rothenberg EV, Sucov HM. A developmental transition in definitive erythropoiesis: erythropoietin expression is sequentially regulated by retinoic acid receptors and HNF4. Genes Dev 2001; 15:889-901. [PMID: 11297512 PMCID: PMC312661 DOI: 10.1101/gad.871601] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The cytokine erythropoietin (Epo) promotes erythropoietic progenitor cell proliferation and is required for erythropoietic differentiation. We have found that the Epo gene is a direct transcriptional target gene of retinoic acid signaling during early erythropoiesis (prior to embryonic day E12.5) in the fetal liver. Mouse embryos lacking the retinoic acid receptor gene RXR alpha have a morphological and histological phenotype that is comparable with embryos in which the Epo gene itself has been mutated, and flow cytometric analysis indicates that RXR alpha-deficient embryos are deficient in erythroid differentiation. Epo mRNA levels are reduced substantially in the fetal livers of RXR alpha(-/-) embryos at E10.25 and E11.25, and genetic analysis shows that the RXR alpha and Epo genes are coupled in the same pathway. We furthermore show that the Epo gene is retinoic acid inducible in embryos, and that the Epo gene enhancer contains a DR2 sequence that represents a retinoic acid receptor-binding site and a retinoic acid receptor transcriptional response element. However, unlike Epo-deficient embryos that die from anemia, the erythropoietic deficiency in RXR alpha(-/-) embryos is transient; Epo mRNA is expressed at normal levels by E12.5, and erythropoiesis and liver morphology are normal by E14.5. We show that HNF4, like RXR alpha a member of the nuclear receptor family, is abundantly expressed in fetal liver hepatocytes, and is competitive with retinoic acid receptors for occupancy of the Epo gene enhancer DR2 element. We propose that Epo expression is regulated during the E9.5--E11.5 phase of fetal liver erythropoiesis by RXR alpha and retinoic acid, and that expression then becomes dominated by HNF4 activity from E11.5 onward. This transition may be responsible for switching regulation of Epo expression from retinoic acid control to hypoxic control, as is found throughout the remainder of life.
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Chang TM, Chan DC, Liu YC, Tsou SS, Chen TH. Long-term results of duodenectomy with highly selective vagotomy in the treatment of complicated duodenal ulcers. Am J Surg 2001; 181:372-6. [PMID: 11438277 DOI: 10.1016/s0002-9610(01)00580-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND Highly selective vagotomy and complete circular or partial duodenectomy have been applied to complicated duodenal ulcer for many years. These procedures seem to provide better clinical results than truncal vagotomy and antrectomy. METHODS A retrospective analysis was conducted of 120 patients with complicated duodenal ulcer who underwent surgical treatment between 1986 and 1999. Patients with obstruction were treated with either circular complete (17) or partial duodenectomy (3) combined with highly selective vagotomy or truncal vagotomy and antrectomy (37). Those with perforation were treated primarily with highly selective vagotomy and partial duodenectomy, highly selective vagotomy alone, or truncal vagotomy and pyloroplasty. Every patient was followed up either by a clinic visit (75%) or questionnaire to determine the presence of ulcer pain, dumping, diarrhea, vomiting, weight loss, and Visick grade. RESULTS Long-term follow-up of patients treated with duodenectomy and highly selective vagotomy for obstruction showed that 94% had sustained weight gain whereas more than half of those treated with truncal vagotomy and antrectomy had weight loss. In patients with perforation, duodenectomy and highly selective vagotomy offered no advantage over highly selective vagotomy alone. CONCLUSIONS Highly selective vagotomy and complete circular or partial duodenectomy provide fewer sequelae and better weight gain long term than truncal vagotomy and antrectomy for patients with obstructing duodenal ulcers.
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Liou HH, Chen RC, Chen TH, Tsai YF, Tsai MC. Attenuation of paraquat-induced dopaminergic toxicity on the substantia nigra by (-)-deprenyl in vivo. Toxicol Appl Pharmacol 2001; 172:37-43. [PMID: 11264021 DOI: 10.1006/taap.2001.9130] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
(-)-Deprenyl (DEP) had been shown to slow of progression of Parkinson's disease (PD). The present study sought to determine whether DEP would attenuate the nigrostriatal system damage induced by intranigral administration of the herbicide paraquat (PQ) as a model of parkinsonism in vivo. Neurochemical and behavioral observations of Wistar rats were the focus of our study. In the neurochemical observation, the PQ injected in the rats caused dose-dependent depletion of dopamine (DA) in the ipsilateral striata. The coadministration of DEP with PQ partially increased the striatal DA level. The prediction of the striatal DA levels was calculated by regression coefficients obtained from multiple linear regression (r(2) = 0.82): DA level (% of control) = 103.34 - 9.58 PQ (nmol) + 0.79 DEP (nmol). It was demonstrated that the high dose of 20 nmol DEP could significant attenuate the PQ (5 nmol)-elicited dopaminergic toxicity (p < 0.05). In the behavioral observation, the intranigral injection of PQ into the rats caused a rotation behavior contralateral to the lesioned side in response to apomorphine administration (0.5 mg/kg, sc). This apomorphine-induced rotational behavior could also be attenuated significantly by coadministration of DEP (20 nmol) and PQ (5 nmol) compared with PQ-treated (5 nmol) animals (p < 0.05). The above observations indicate that DEP could provide a protective effect on the moderate injury elicited by PQ toxicity of the nigrostriatal dopaminergic system. DEP might be a useful therapeutic agent in treating patients with early-stage PD.
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Hori G, Wang MF, Chan YC, Komatsu T, Wong Y, Chen TH, Yamamoto K, Nagaoka S, Yamamoto S. Soy protein hydrolyzate with bound phospholipids reduces serum cholesterol levels in hypercholesterolemic adult male volunteers. Biosci Biotechnol Biochem 2001; 65:72-8. [PMID: 11272848 DOI: 10.1271/bbb.65.72] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study was done to evaluate the effects of soy protein hydrolyzate with bound phospholipids (c-SPHP), on the serum cholesterol levels in hypercholesterolemic subjects over a three-month period. Subjects were Taiwanese adult male volunteers whose serum total cholesterol levels were above 220 mg/dl. Twenty-one subjects were divided into three groups randomly, and each group was given c-SPHP zero, 3, or 6 g per day. Test diets were orally administered in a powdered drink form that contained c-SPHP or casein hydrolyzate (placebo). The subjects were given the test diet four times daily. The study consisted of a two-week pre-feeding period, a three-month feeding period, followed by a two-week post-feeding period. After 3 months of c-SPHP administration, 3 g per day, serum total cholesterol decreased significantly from the initial level (15.0%, p<0.01) and compared with the placebo group (p<0.05). Furthermore, LDL-cholesterol decreased significantly (27.7%, p<0.01) and the LDL/HDL ratio also decreased significantly (47.4%, p<0.01) from the initial levels. These effects of c-SPHP were dose-dependent. This study suggests that c-SPHP has remarkable improving effects on the serum cholesterol levels in hypercholesterolemic subjects.
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Chen TH, Wang MF, Liang YF, Komatsu T, Chan YC, Chung SY, Yamamoto S. A nucleoside-nucleotide mixture may reduce memory deterioration in old senescence-accelerated mice. J Nutr 2000; 130:3085-9. [PMID: 11110874 DOI: 10.1093/jn/130.12.3085] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We investigated the effects of a mixture of dietary nucleosides and nucleotides (NS + NT) on memory in 1- and 7-mo-old senescence-accelerated mice (SAM). Memory retention was studied with passive avoidance (step-through) and active avoidance (shuttle) tests. For 14 wk, mice in the control groups were fed a 20 g of casein/100 g diet, whereas the NS + NT groups were fed this diet supplemented with a 0.5 g of NS + NT mixture/100 g. All mice were killed at wk 14, and we studied the brain histopathology. Lipofuscin, monovacuoles and multiple vacuoles of various brain regions were measured. Body weight, food intake and ambulatory activity did not differ between the control and NS + NT groups. In old mice, the time of passive avoidance was significantly higher in the NS + NT group than in the control group at d 1 and 7 (P: < 0.05). However, such an effect of NS + NT was not observed in young mice. In the active avoidance test, the incidence of successful avoidance in old mice was higher in the NS + NT group than in the control group at d 1 and 2 (P: < 0.05). The percentages of specific brain cells containing lipofuscin were lower in NS + NT groups than in the control groups in both young and old mice (P: < 0.05). The number of monovacuoles and multiple vacuoles in specific brain regions tended to be lower (P: = 0.1-0.25) in NS + NT than in control groups, with significant differences in the microvacuoles of the middle cortex of young mice and in the multiple vacuoles in the hind cortex of old mice (P: < 0. 05). These results suggest that increased dietary NS + NT may be associated with decreases in the age-induced deterioration of brain morphology and certain memory tasks.
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Chang HJ, Kuo HS, Tung TH, Chou P, Chen TH. Evaluation of a population-based screening for type 2 diabetes: a community-based screening project in Puli, Taiwan. Prev Med 2000; 31:396-402. [PMID: 11006065 DOI: 10.1006/pmed.2000.0728] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND A Markov method incorporating the relationships between prevalence, incidence, and mortality with respect to type 2 diabetes was used to assess a population-based screening for this disease. METHODS Data from a population-based screening project for residents of Puli, Taiwan, over 30 years of age (n= 1,219) were used to estimate the annual incidence of asymptomatic type 2 diabetes, the prevalence to incidence (P/I) ratio, and the hazard rate of death due to type 2 diabetes. These parameters were employed to develop a Markov process to evaluate the effects of early detection of type 2 diabetes on the risk of death from this disease in a simulated population (n= 10,000) receiving biennial, 5-year interval, or no screening. RESULTS The estimated annual incidence, average duration from asymptomatic to symptomatic type 2 diabetes (P/I ratio), and hazard rate for death from this disease were 0.86% (95% CI 0.50-1.48), 10 years (95% CI 7.69-14.01), and 1.1% per year, respectively. This yields an optimal screening interval of 5 years. Simulation of a 5-year interval screening regimen versus no screen ing yielded a relative risk reduction of 31% (95% CI 12-46%). A similar value was found for a biennial screening regime. CONCLUSIONS The results suggest that early detection of type 2 diabetes via a community-based screening project in developing countries with high prevalence is worthwhile.
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Cheng AT, Chen TH, Chen CC, Jenkins R. Psychosocial and psychiatric risk factors for suicide. Case-control psychological autopsy study. Br J Psychiatry 2000; 177:360-5. [PMID: 11116779 DOI: 10.1192/bjp.177.4.360] [Citation(s) in RCA: 286] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Few studies of suicide have simultaneously examined the individual and combined effects of psychosocial and psychiatric risk factors. AIMS To do so in a representative sample of suicides. METHOD A case-control psychological autopsy was conducted among 113 consecutive suicides and 226 living controls matched for age, gender, ethnicity and area of residence in Taiwan. RESULTS Five major risk factors (loss event, suicidal behaviour in first-degree relatives, ICD-10 major depressive episode, emotionally unstable personality disorder and substance dependence) were found to have independent effects on suicide from multivariate conditional logistic regression analysis. CONCLUSIONS Effective intervention and management for loss event and major depressive episode among emotionally unstable subjects with a family tendency of suicidal behaviour, frequently also comorbid with alcohol or other substance dependence, may prove to be most effective for suicide prevention in different populations.
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Zhang SZ, Dong MM, Teng XJ, Chen TH, Zhang S. [Quantitative assay of telomerase activity in head and neck squamous cell carcinoma]. LIN CHUANG ER BI YAN HOU KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY 2000; 14:393-5. [PMID: 12563906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To detect and quantify telomerase activity in tissues from head and neck squamous cell carcinoma (HNSCC), and to explore whether the levels of telomerase activity can be a useful marker for cancer risk assessment in HNSCC. METHOD The levels of telomerase activity of 55 fresh specimens obtained from 25 patients with HNSCC were detected by the method of telomeric repeat scintillation radioactive count, including 25 primary tumors, 7 samples of neck metastases and 23 corresponding normal tissues as control. In 7 patients, both primary and metastatic tumors were obtained. The levels of telomerase activity were determined with a liquid scintillation counter. The basic principle of the technique is that a G-rich oligonucleotide strand of telomeric sequence is used as primer, 3H-dTTPs are incorporated into the products while telomerase elongates the primers, and then free 3H-dTTPs are removed by rinsing step, finally radioactive count per minute (cpm) of products is detected, and the levels telomerase activity can be evaluated according to the value (cpm). RESULT 1. The levels of telomerase activity (cpm) in tissues with HNSCC were significantly higher than those in the normal tissues (P < 0.05); 2. The levels of telomerase activity in the primary tumors were higher than those of their neck metastases, but the difference was not statistical significance (P > 0.05); 3. The levels of telomerase activity in the neck metastases were remarkably higher than those in the normal tissues (P < 0.05). CONCLUSION 1. Detection of telomerase activity in HNSCCs can be a useful marker for cancer assessment. 2. To quantify telomerase activity may have clinical diagnostic value for HNSCC. 3. The levels of telomerase activity in the metastatic lymph nodes were higher.
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