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Sun ZR, Han Y, Liu YH, Chen TF, Li YB, Zhang GJ, Pan XB. [Application value of image fusion technology in transcatheter aortic valve implantation]. Zhonghua Yi Xue Za Zhi 2023; 103:665-670. [PMID: 36858366 DOI: 10.3760/cma.j.cn112137-20220818-01762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Objective: To analysis the application value of image fusion technology in transcatheter aortic valve implantation (TAVI). Methods: A total of 35 patients underwent trans-femoral TAVI using the first-generation VENUS-A valve in Heart Center of Henan Provincial People's Hospital from January 2020 to May 2021 were analyzed retrospectively. Among them, there were 21 males and 14 females, aged from 64 to 81 years, with a mean (SD) of (71.37±5.66) years. They were divided into conventional group (n=22) and fusion group (n=13), according to whether image fusion technology was used during operation. The preoperative general data, intraoperative data, differences of postoperative renal function and residence time in intensive care unit (ICU) were analyzed and compared between the two groups. The postoperative echocardiography and 12 lead ECG were observed. Results: All 35 patients in this study were with severe aortic stenosis, of which, 10 patients were complicated with moderate to severe regurgitation. Compared with the conventional group, the intraoperative fusion group had fewer angiography times [3.0 (3.0, 4.0) vs 5.0 (5.0, 6.0)], X-ray absorbed dose [342.0 (44.5) mGy vs 388.4 (71.0) mGy], and contrast dosage [(73.5±10.5) ml vs (90.3±10.3) ml], and shorter rapid pacing time [(14.0±1.6) seconds vs (16.5±2.0) seconds] (all P<0.05). There was no significant differences in X-ray irradiation time, operation time, sizing of the pre-dilated balloon, valve implantation depth and other indicators (all P>0.05). There was no significant differences in ICU retention time and postoperative renal function (all P>0.05). Postoperative echocardiography showed that the function of aortic valve was good, with mild perivalvular leakage in 2 cases in the conventional group and 1 case in the fusion group; and one patient was implanted with permanent pacemaker after TAVI in the conventional group. Conclusion: Image fusion technology simplifies the TAVI process, shortens the ventricular pacing time and reduces the dosage of X-ray and contrast, and has certain clinical application value.
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Affiliation(s)
- Z R Sun
- Department of Structural Heart Disease of Heart Center of Henan Provincial People's Hospital, Zhengzhou University Central China Fuwai Hospital, Zhengzhou 450000, China
| | - Y Han
- Department of Structural Heart Disease of Heart Center of Henan Provincial People's Hospital, Zhengzhou University Central China Fuwai Hospital, Zhengzhou 450000, China
| | - Y H Liu
- Department of Structural Heart Disease of Heart Center of Henan Provincial People's Hospital, Zhengzhou University Central China Fuwai Hospital, Zhengzhou 450000, China
| | - T F Chen
- Department of Structural Heart Disease of Heart Center of Henan Provincial People's Hospital, Zhengzhou University Central China Fuwai Hospital, Zhengzhou 450000, China
| | - Y B Li
- Department of Structural Heart Disease of Heart Center of Henan Provincial People's Hospital, Zhengzhou University Central China Fuwai Hospital, Zhengzhou 450000, China
| | - G J Zhang
- Center of Structural Heart Disease of Fuwai Hospital of the Chinese Academy of Medical Sciences National Center Cardiovascular Disease, Beijing 100037, China
| | - X B Pan
- Center of Structural Heart Disease of Fuwai Hospital of the Chinese Academy of Medical Sciences National Center Cardiovascular Disease, Beijing 100037, China
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Song M, Liu Y, Wang XJ, Zhang LW, Liu Q, Chen TF, Su X, Li WW, Lyu LX, Yang YF. [Association of glutamate receptor metabotropic 5 polymorphisms with schizophrenia susceptibility in a Chinese Han population]. Zhonghua Yi Xue Za Zhi 2022; 102:2108-2114. [PMID: 35844113 DOI: 10.3760/cma.j.cn112137-20211125-02631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objectives: To investigate the association of single nucleotide polymorphisms (SNP) of glutamate receptor metabotropic 5 (GRM5) gene with schizophrenia susceptibility(SZ) in a Chinese Han population. Methods: Twenty-two SNPs located in GRM5 gene in 528 paranoid SZ patients and 528 control subjects recruited from northern Henanwere analyzed. The clinical features of 267 first-episode SZ patients were assessed with the Positive and Negative Syndrome Scale (PANSS). Results: The SZ group included 264 males and 264 females, aged (27±8) years; the healthy control group had 264 males and 264 females, aged (28±8) years.The differences in the genotypic and allelic frequencies of two SNPs (rs567990 and rs12421343) were statistically significant between the SZ patients and control groups (all P<0.05). The allele frequency of rs504183 was also statistically different between the two groups (P=0.030). When the subjects were stratified by sex, the genotypic and allelic frequencies of rs12421343 in female subjects were statistically different between the SZ patients and control groups. The allele frequencies of SNPs (rs12422021, rs567990, and rs7101540) were also statisticallydifferent between the two groups (all P<0.05). Meanwhile, rs567990 AG+GG carriers had a higher risk for SZ than AA carriers in female subjects(OR=1.946, 95%CI: 1.264-2.995). In addition, the patients with different genotypes (GG, AA+AG) of rs12422021 showed statistically significant differences in PANSS total score(84.8±24.4 vs 75.3±18.6), positive (16.2±4.3 vs 14.4±4.2), excitement (12.4±5.1 vs 10.2±4.1) and cognitive impairment factor scores (15.2±6.8 vs 13.3±3.9) (all P<0.05). The patients with AC and the other two genotypes (AA and CC) of rs504183 showed statistically significant differences in PANSS negative factor score(27.4±9.9 vs 24.7±8.4 and 23.4±8.1, both P<0.05). Conclusion: The current study provides further evidence that GRM5 is associated with SZ, and suggests a putative sex difference.
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Affiliation(s)
- M Song
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - Y Liu
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - X J Wang
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - L W Zhang
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - Q Liu
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - T F Chen
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - X Su
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - W W Li
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - L X Lyu
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
| | - Y F Yang
- Department of Psychiatry, the Second Affiliated Hospital of Xinxiang Medical University, Henan Mental Hospital, Henan Key Lab of Biological Psychiatry, Xinxiang 453002, China
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Wu Z, Chen TF, Zeng ZF, Zhang YW, Tang Z, Su KY, Fan CY, Li SL. Genetic Structure Analysis of Y-Chromosome STR and SNP in Population of Wujiang Area, Suzhou City. Fa Yi Xue Za Zhi 2019; 35:448-454. [PMID: 31532156 DOI: 10.12116/j.issn.1004-5619.2019.04.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Indexed: 11/30/2022]
Abstract
Abstract Objective To analyze the genetic phenotypes of Y-chromosome STR and SNP in Han male population of Wujiang area, Suzhou City and explore the genetic structure of population of Wujiang area for further examination of regional-specific Y-SNP genetic markers ancestor haplogroups. Methods Blood samples of 472 Wujiang area Han males were randomly collected and genotyped by YfilerTM Plus PCR Amplification Kit. The allele frequencies and haplotype frequencies of each locus were obtained using the direct calculation method. Y-SNP haplogroups of each sample were estimated using Y-Predictor software and verified through experiments by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Results A total of 453 haplotypes were found in the 27 Y-STR genetic markers in 472 Han males of Wujiang area. The haplotype diversity (HD) was 0.997 696 93, among which, the highest gene diversity (GD) value was DYF387S1a/b (GD=0.953 1) and the lowest was DYS438 (GD=0.321 8). Based on genotyping data of 27 Y-STRs and 472 samples, 132 haplogroups from C, D, N, O and Q, etc downstream Y-SNP haplogroups were estimated and then verified through experiments. Conclusion This study is based on Y-chromosome STR haplotypes, and predicts Y-SNP haplogroups by Y-Predictor software, then uses ARMS-PCR to verify. Y-SNP genetic markers were introduced to achieve precise analysis of the genetic structure of male families in population of three towns in Wujiang area.
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Affiliation(s)
- Z Wu
- School of Life Sciences, Fudan University, Shanghai 200438, China.,Wujiang District Public Security Bureau of Suzhou, Suzhou 215200, Jiangsu Province, China
| | - T F Chen
- Wujiang District Public Security Bureau of Suzhou, Suzhou 215200, Jiangsu Province, China
| | - Z F Zeng
- Wujiang District Public Security Bureau of Suzhou, Suzhou 215200, Jiangsu Province, China
| | - Y W Zhang
- School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Z Tang
- School of Life Sciences, Fudan University, Shanghai 200438, China
| | - K Y Su
- School of Life Sciences, Fudan University, Shanghai 200438, China
| | - C Y Fan
- School of Life Sciences, Fudan University, Shanghai 200438, China
| | - S L Li
- School of Life Sciences, Fudan University, Shanghai 200438, China
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Sawan M, Jeon YH, Chen TF. 84PSYCHOTROPIC MEDICINES USE IN RESIDENTS AND CULTURE: INFLUENCING CLINICAL EXCELLENCE (PRACTICE) TOOL: A DEVELOPMENT AND CONTENT VALIDATION STUDY. Age Ageing 2019. [DOI: 10.1093/ageing/afz061.05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- M Sawan
- Faculty of Pharmacy, University of Sydney, Camperdown, NSW, Australia
| | - Y -H Jeon
- Faculty of Nursing, University of Sydney
| | - T F Chen
- Faculty of Pharmacy, University of Sydney, Camperdown, NSW, Australia
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Benetoli A, Chen TF, Aslani P. How patients' use of social media impacts their interactions with healthcare professionals. Patient Educ Couns 2018; 101:439-444. [PMID: 28882545 DOI: 10.1016/j.pec.2017.08.015] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 07/15/2017] [Accepted: 08/27/2017] [Indexed: 06/07/2023]
Abstract
INTRODUCTION Patients are increasingly accessing online health information and have become more participatory in their engagement with the advent of social media (SM). This study explored how patients' use of SM impacted their interactions with healthcare professionals (HCPs). METHODS Focus groups (n=5) were conducted with 36 patients with chronic conditions and on medication who used SM for health-related purposes. The discussions lasted 60-90min, were audio-recorded, transcribed verbatim, and thematically analysed. RESULTS Participants did not interact with HCPs on SM and were not expecting to do so as they used SM exclusively for peer interactions. Most reported improvement in the patient-HCP relationship due to increased knowledge, better communication, and empowerment. Participants supplemented HCP-provided information with peer interactions on SM, and prepared themselves for consultations. They shared online health information with HCPs, during consultations, to validate it and to actively participate in the decision-making. Although some participants reported HCP support for their online activities, most perceived overt or tacit opposition. CONCLUSION Participants perceived that their SM use positively impacted relationships with HCPs. They felt empowered and were more assertive in participating in decision-making. PRACTICE IMPLICATIONS HCPs should be aware of patients' activities and expectations, and support them in their online activities.
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Affiliation(s)
- A Benetoli
- Pharmacy and Bank Building A15, The University of Sydney, NSW 2006, Australia; Department of Pharmaceutical Sciences, State University of Ponta Grossa, Parana 84.030-900, Brazil.
| | - T F Chen
- Pharmacy and Bank Building A15, The University of Sydney, NSW 2006, Australia.
| | - P Aslani
- Pharmacy and Bank Building A15, The University of Sydney, NSW 2006, Australia.
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Ho SS, McLachlan AJ, Chen TF, Hibbs DE, Fois RA. Relationships Between Pharmacovigilance, Molecular, Structural, and Pathway Data: Revealing Mechanisms for Immune-Mediated Drug-Induced Liver Injury. CPT Pharmacometrics Syst Pharmacol 2015; 4:426-41. [PMID: 26312166 PMCID: PMC4544056 DOI: 10.1002/psp4.56] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 05/08/2015] [Indexed: 11/18/2022]
Abstract
Immune-mediated drug-induced liver injury (IMDILI) can be devastating, irreversible, and fatal in the absence of successful transplantation surgery. We present a novel approach that combines the methods of pharmacoepidemiology with in silico molecular modeling to identify specific features in toxic ligands that are associated with clinical features of IMDILI. Specifically, from pharmacovigilance data multivariate logistic regression identified 18 drugs associated with IMDILI (P < 0.00015). Eleven of these drugs, along with their known and proposed metabolites, constituted a training set used to develop a four-point pharmacophore model (sensitivity 75%; specificity 85%). Subsequently, this information was combined with information from immune-pathway reviews and genetic-association studies and complemented with ligand-protein docking simulations to support a hypothesis implicating two putative targets within separate, possibly interacting, immune-system pathways: the major histocompatibility complex within the adaptive immune system and Toll-like receptors (TLRs), in particular TLR-7, which represent pattern recognition receptors of the innate immune system.
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Affiliation(s)
- S S Ho
- Faculty of Pharmacy (A15), University of Sydney Sydney, NSW, Australia
| | - A J McLachlan
- Faculty of Pharmacy (A15), University of Sydney Sydney, NSW, Australia
| | - T F Chen
- Faculty of Pharmacy (A15), University of Sydney Sydney, NSW, Australia
| | - D E Hibbs
- Faculty of Pharmacy (A15), University of Sydney Sydney, NSW, Australia
| | - R A Fois
- Faculty of Pharmacy (A15), University of Sydney Sydney, NSW, Australia
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Gisev N, Bell JS, Chen TF. A retrospective study of psychotropic drug use among individuals with mental illness issued a community treatment order. Int J Clin Pract 2014; 68:236-44. [PMID: 24372715 DOI: 10.1111/ijcp.12276] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Accepted: 08/02/2013] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Community treatment orders (CTOs) are legal orders which require individuals with mental illness to accept treatment in the community. Previous studies report that long-acting injectable (LAI) antipsychotics are associated with CTOs, however, little is known about the specific treatment plans prescribed in CTOs. The objective of this study was to describe the patterns of psychotropic drugs prescribed to individuals issued a CTO, focusing on LAI antipsychotics, antipsychotic polypharmacy and high-dose antipsychotics. METHODS This was a retrospective cross-sectional study of 378 individuals randomly selected from a sample of 1317 individuals with a CTO expiry date up to and including 30 April 2010, taken from all 2856 individuals issued a CTO by the New South Wales Mental Health Review Tribunal, Australia, in 2009. De-identified information relating to individuals' treatment plans, demographic and clinical details were systematically extracted. RESULTS A total of 377 (99.7%) individuals were prescribed at least one antipsychotic. Of these, 310 (82%) were prescribed a LAI antipsychotic, either alone (45%), or in combination with, an oral antipsychotic (37%). Risperidone was the most prevalent antipsychotic, prescribed to 164 (43%) individuals. Antipsychotic polypharmacy was prescribed to 121 (32%) individuals and between 20% and 27% of individuals were prescribed high-dose antipsychotics. Antipsychotic polypharmacy accounted for 74-80% of individuals prescribed high-dose antipsychotics. CONCLUSIONS The results from this study confirm that LAI antipsychotics are commonly prescribed in CTOs. Antipsychotic polypharmacy was also common, and accounted for the majority of individuals prescribed high-dose antipsychotics. Further research is needed to determine the potential outcomes and implications of the patterns observed.
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Affiliation(s)
- N Gisev
- Faculty of Pharmacy, The University of Sydney, Sydney, NSW, Australia
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Abstract
Non-adherence to antidepressant medications is a significant barrier to the successful treatment of depression in clinical practice. This review aims to systematically assess the effectiveness of interventions for improving antidepressant medication adherence among patients with unipolar depression, and to evaluate the effect of these interventions on depression clinical outcomes. MEDLINE, PsycINFO and EMBASE databases were searched for English-language randomised controlled trials published between January 1990 and December 2010 on interventions to improve antidepressant adherence. The impact of interventions on antidepressant medication adherence (compliance and persistence) and depression clinical outcomes was evaluated. Data concerning the quality of the included studies were also extracted. Twenty-six studies met the inclusion criteria. Interventions were classified as educational, behavioural and multifaceted interventions. A total of 28 interventions were tested, as two studies investigated two interventions each. Sixteen (57%) of the 28 interventions showed significant effects on antidepressant adherence outcomes, whereas 12 (43%) interventions demonstrated significant effects on both antidepressant adherence and depression outcomes. The interventions which showed significant improvement in outcomes were primarily multifaceted and complex, with proactive care management and involvement of mental health specialists. The most commonly used elements of multifaceted interventions included patient educational strategies, telephone follow-up to monitor patients' progress, as well as providing medication support and feedback to primary care providers. Overall, educational interventions alone were ineffective in improving antidepressant medication adherence. In conclusion, improving adherence to antidepressants requires a complex behavioural change and there is some evidence to support behavioural and multifaceted interventions as the most effective in improving antidepressant medication adherence and depression outcomes. More carefully designed and well-conducted studies are needed to clarify the effect of interventions in different patient populations and treatment settings.
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Affiliation(s)
- W W Chong
- Faculty of Pharmacy, The University of Sydney, NSW, Australia.
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Bell JS, Aaltonen SE, Airaksinen MS, Volmer D, Gharat MS, Muceniece R, Vitola A, Foulon V, Desplenter FA, Chen TF. Determinants of mental health stigma among pharmacy students in Australia, Belgium, Estonia, Finland, India and Latvia. Int J Soc Psychiatry 2010; 56:3-14. [PMID: 19861340 DOI: 10.1177/0020764008097621] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Healthcare professionals commonly exhibit negative attitudes toward people with mental disorders. Few international studies have sought to investigate the determinants of stigma. OBJECTIVE To conduct an international comparison of pharmacy students' stigma towards people with schizophrenia, and to determine whether stigma is consistently associated with stereotypical attributes of people with schizophrenia. METHOD Students (n = 649) at eight universities in Australia, Belgium, India, Finland, Estonia and Latvia completed a seven-item Social Distance Scale (SDS) and six items related to stereotypical attributes of people with schizophrenia. RESULTS Mean SDS scores were 19.65 (+/- 3.97) in Australia, 19.61 (+/- 2.92) in Belgium, 18.75 (+/- 3.57) in India, 18.05 (+/- 3.12) in Finland, and 20.90 (+/- 4.04) in Estonia and Latvia. Unpredictability was most strongly associated with having a high social distance in Australia (beta = -1.285), the perception that people will never recover in India (beta = - 0.881), dangerousness in Finland (beta = -1.473) and the perception of being difficult to talk to in Estonia and Latvia (beta = -2.076). Unpredictability was associated with lower social distance in Belgium (beta = 0.839). CONCLUSION The extent to which students held stigmatizing attitudes was similar in each country, however, the determinants of stigma were different. Pharmacy education may need to be tailored to address the determinants of stigma in each country.
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Affiliation(s)
- J S Bell
- Division of Social Pharmacy, University of Helsinki, Finland.
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Lin YC, Liang YC, Sheu MT, Lin YC, Hsieh MS, Chen TF, Chen CH. Chondroprotective effects of glucosamine involving the p38 MAPK and Akt signaling pathways. Rheumatol Int 2008; 28:1009-16. [PMID: 18340449 DOI: 10.1007/s00296-008-0561-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2007] [Accepted: 03/01/2008] [Indexed: 01/18/2023]
Abstract
The purpose of the present study was to elucidate the possible signal transduction pathway involved in the underlying mechanism of glucosamine (GLN)'s influence on the gene expression of matrix metalloproteinases (MMPs) in chondrocytes stimulated with IL-1beta. Using chondrosarcoma cells stimulated with IL-1beta, the effects of GLN on the mRNA and protein levels of MMP-3, the activation of JNK, ERK, p38, NF-kappaB, and AP-1, the nuclear translocation of NF-kappaB/Rel family members, and PI3-kinase/Akt activation were studied. GLN inhibited the expression and the synthesis of MMP-3 induced by IL-1beta, and that inhibition was mediated at the level of transcription involving both the NF-kappaB and AP-1 transcription factors. Translocation of NF-kappaB was reduced by GLN as a result of the inhibition of IkappaB degradation. A slightly synergistic effect on the activation of AP-1 induced by IL-1beta was shown in the presence of GLN. Among MAPK pathways involved in the transcriptional regulation of AP-1, phosphorylation of JNK and ERK was found to increase with the presence of GLN under IL-1beta treatment, while that for p38 decreased. It was also found that GLN alone, but also synergistically with IL-1beta, was able to activate the Akt pathway. The requirements of NF-kappaB translocation and p38 activity are indispensably involved in the induction of MMP-3 expression in chondrosarcoma cells stimulated by IL-1beta. Inhibition of the p38 pathway in the presence of GLN substantially explains the chondroprotective effect of GLN on chondrocytes that regulate COX-2 expression, PGE(2) synthesis, and NO expression and synthesis. The chondroprotective effect of GLN through the decrease in MMP-3 production and stimulation of proteoglycan synthesis may follow another potential signaling pathway of Akt.
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Affiliation(s)
- Yi-Cheng Lin
- Department of Orthopedics, Mackay Memorial Hospital, Taipei, Taiwan, ROC
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Chou DS, Lee JJ, Hsiao G, Hsieh CY, Tsai YJ, Chen TF, Sheu JR. Baicalein induction of hydroxyl radical formation via 12-lipoxygenase in human platelets: an ESR study. J Agric Food Chem 2007; 55:649-55. [PMID: 17263456 DOI: 10.1021/jf062584f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The pro-oxidant activities of baicalein, morin, myricetin, quercetin, and rutin were examined in various cell-containing systems including human platelets, rat vascular smooth muscle cells, human umbilical vein endothelial cells (HUVECs), human THP-1 cells, and fibroblast cells. Electron spin resonance (ESR) results showed that only baicalein generated hydroxyl radicals in a resting human platelet suspension, whereas the other flavonoids showed no effects on any of the resting cell systems. A low concentration of arachidonic acid (AA) increased the intensity of hydroxyl radicals, but a high concentration inhibited it. Collagen and thrombin, platelet aggregatory agents that can cause the release of AA by platelets, enhanced baicalein-induced hydroxyl radical formation, whereas ADP and U44619 showed no significant effects. Quinacrine and 5,8,11,14-eicosatetraenoic trifluoromethyl ketone, both PLA2 inhibitors, significantly attenuated baicalein-induced hydroxyl radical formation. These results suggest that baicalein-induced hydroxyl radical formation is associated with AA metabolite enzymes in human platelets. The formation of hydroxyl radicals was significantly inhibited by lipoxygenase inhibitors including nordihydroguaiaretic acid, (-)-epicatechin, (-)-epicatechin gallate, and hinokitiol, but was not affected by desferroxamine or the heme protein inhibitors KCN and NaN3. On the other hand, semiquinone free radicals were generated when baicalein was incubated with horseradish peroxidase/H2O2 or platelets/AA. The semiquinone radicals formed in the platelets/AA system could be extensively inhibited by desferroxamine, diethylenetriaminepentaacetic acid, KCN, and NaN3, indicating that prostaglandin H synthase (PGHS)-peroxidase may be involved. The results of this study led to the proposal that baicalein induces hydroxyl radical formation via 12-lipoxygenase and induces semiquinone radical formation via PGHS-peroxidase in human platelets.
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Affiliation(s)
- Duen-Suey Chou
- Graduate Institutes of Pharmacology and Medical Sciences, Taipei Medical University, No. 250 Wu-Hsing Street, Taipei 110, Taiwan
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Chen CH, Sheu MT, Chen TF, Wang YC, Hou WC, Liu DZ, Chung TC, Liang YC. Suppression of endotoxin-induced proinflammatory responses by citrus pectin through blocking LPS signaling pathways. Biochem Pharmacol 2006; 72:1001-9. [PMID: 16930561 DOI: 10.1016/j.bcp.2006.07.001] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2006] [Revised: 06/19/2006] [Accepted: 07/02/2006] [Indexed: 11/30/2022]
Abstract
Pectin is composed of complex polysaccharides rich in galactoside residues, and it is most abundant in citrus fruits. Pectin and modified pectin have been found to exhibit anti-mutagenic activity and inhibit cancer metastasis and proliferation, with no evidence of toxicity or other serious side effects. In this study, we investigated the inhibitory effect of pectin at different degrees of esterification (DEs) on the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-activated macrophages. Western blot and RT-PCR analyses demonstrated that 30% esterified pectin (DE30), DE60 pectin, and DE90 pectin significantly inhibited the protein and mRNA expressions of iNOS and COX-2 in LPS-activated macrophages, and DE90 pectin was the most-potent inhibitor. To clarify the mechanisms involved, DE90 pectin was found to inhibit the phosphorylation of MAPKs and IKK kinase activity. In addition, DE90 pectin inhibited the activation of NF-kappaB and AP-1 by electrophoretic mobility shift assay and transient transfection experiments. Finally, we found that DE90 pectin could bind with LPS, and might result in decreased binding of LPS to its receptor. These results suggest that modulation of iNOS and COX-2 expressions by dietary pectin may be important in cancer chemoprevention and anti-inflammation.
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Affiliation(s)
- Chien-Ho Chen
- School of Medical Laboratory Science & Biotechnology, College of Medicine, Taipei Medical University, No. 250 Wu-Hsing Street, Taipei 11014, Taiwan, ROC
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Chen RM, Wu GJ, Chang HC, Chen JT, Chen TF, Lin YL, Chen TL. 2,6-Diisopropylphenol Protects Osteoblasts from Oxidative Stress-Induced Apoptosis through Suppression of Caspase-3 Activation. Ann N Y Acad Sci 2006; 1042:448-59. [PMID: 15965091 DOI: 10.1196/annals.1338.038] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
2,6-Diisopropylphenol is an intravenous anesthetic agent used for induction and maintenance of anesthesia. Since it is similar to alpha-tocopherol, 2,6-diisopropylphenol may have antioxidant effects. Osteoblasts play important roles in bone remodeling. In this study, we attempted to evaluate the protective effects of 2,6-diisopropylphenol on oxidative stress-induced osteoblast insults and their possible mechanisms, using neonatal rat calvarial osteoblasts as the experimental model. Clinically relevant concentrations of 2,6-diisopropylphenol (3 and 30 microM) had no effect on osteoblast viability. However, 2,6-diisopropylphenol at 300 microM time-dependently caused osteoblast death. Exposure to sodium nitroprusside (SNP), a nitric oxide donor, increased amounts of nitrite in osteoblasts. 2,6-Diisopropylphenol did not scavenge basal or SNP-releasing nitric oxide. Hydrogen peroxide (HP) enhanced levels of intracellular reactive oxygen species in osteoblasts. 2,6-Diisopropylphenol significantly reduced HP-induced oxidative stress. Exposure of osteoblasts to SNP and HP decreased cell viability time-dependently. 2,6-Diisopropylphenol protected osteoblasts from SNP- and HP-induced cell damage. Analysis by a flow cytometric method revealed that SNP and HP induced osteoblast apoptosis. 2,6-Diisopropylphenol significantly blocked SNP- and HP-induced osteoblast apoptosis. Administration of SNP and HP increased caspase-3 activities. However, 2,6-diisopropylphenol significantly decreased SNP- and HP-enhanced caspase-3 activities. This study shows that a therapeutic concentration of 2,6-diisopropylphenol can protect osteoblasts from SNP- and HP-induced cell insults, possibly via suppression of caspase-3 activities.
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Affiliation(s)
- Ruei-Ming Chen
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, No. 111, Hsing-Lung Rd., Sec. 3, Taipei 116, Taiwan.
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14
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Chou DS, Chan CH, Hsiao G, Shen MY, Tsai YJ, Chen TF, Sheu JR. Inhibitory mechanisms of low concentrations of oxidized low-density lipoprotein on platelet aggregation. J Biomed Sci 2005; 13:333-43. [PMID: 16283430 DOI: 10.1007/s11373-005-9042-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2005] [Accepted: 10/11/2005] [Indexed: 11/25/2022] Open
Abstract
The intracellular mechanisms underlying oxidized low-density lipoprotein (oxLDL)-signaling pathways in platelets are not yet completely understood. Therefore, the aim of this study was to further examine the effects of oxLDL in prevention of platelet aggregation. In this study, oxLDL concentration-dependently (40-120 microg/ml) inhibited platelet aggregation in human platelet-rich plasma stimulated by agonists. Moreover, oxLDL (40 and 80 microg/ml) markedly decreased the fluorescence intensity of platelet membranes tagged with diphenylhexatriene. Rapid phosphorylation of a protein of Mr 47,000 (P47), a marker of protein kinase C activation, was triggered by PDBu (150 nM). This phosphorylation was markedly inhibited by oxLDL (40 and 80 microg/ml) in phosphorus-32-labeled platelets. In addition, oxLDL (40 and 80 microg/ml) markedly increased levels of cyclic AMP and cyclic AMP-induced vasodilator-stimulated phosphoprotein (VASP) Ser(157) phosphorylation. The thrombin-evoked increase in pHi was inhibited in the presence of oxLDL (40 and 80 microg/ml). These results indicate that the antiplatelet activity of oxLDL may involve the following pathways. (1) oxLDL may initially induce conformational changes in platelet membranes, leading to inhibition of the activation of protein kinase C, followed by inhibition of P47 protein phosphorylation, and intracellular Ca(2+) mobilization. (2) oxLDL also activated formation of cyclic AMP and cyclic AMP-induced VASP Ser(157) phosphorylation, resulting in inhibition of the Na(+)/H(+)exchanger; this leads to reduced intracellular Ca(2+) mobilization, and ultimately to inhibition of platelet aggregation. This study further provides new insights concerning the effects of low concentrations of oxLDL on platelet aggregation.
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Affiliation(s)
- Duen-Suey Chou
- Graduate Institute of Medical Sciences, Taipei Medical University, Taiwan, ROC
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15
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Hon N, Lynn N, Chen TF. Transanal resection of the prostate. Ann R Coll Surg Engl 2005; 87:489. [PMID: 16263028 PMCID: PMC1964103 DOI: 10.1308/003588405x71117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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16
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Chou DS, Hsiao G, Shen MY, Tsai YJ, Chen TF, Sheu JR. ESR spin trapping of a carbon-centered free radical from agonist-stimulated human platelets. Free Radic Biol Med 2005; 39:237-48. [PMID: 15964515 DOI: 10.1016/j.freeradbiomed.2005.03.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2004] [Revised: 02/21/2005] [Accepted: 03/10/2005] [Indexed: 01/14/2023]
Abstract
Several free radical intermediates formed during synthesis of prostaglandin H synthase (PGHS) catalyze the biosynthesis of prostaglandins from arachidonic acid (AA). We attempted to directly detect free radical intermediates of PGHS in cells. Studies were carried out using human platelets, which possess significant PGHS activity. Electron spin resonance (ESR) spectra showed a g = 2.005 signal radical, which was formed by the incubation of collagen, thrombin, AA, and a variety of peroxides with human platelets. The ESR spectra obtained using 5,5-dimethyl-1 pyrroline N-oxide (DMPO) and alpha-phenyl N-tert.-butylnitron (PBN) were typical of an immobilized nitroxide. Extensive Pronase digestion of both the DMPO and PBN adducts allowed us to deduce that it was a carbon-centered radical. The formation of this radical was inhibited by potassium cyanide and by desferroxamine. Peroxides stimulated formation of the g = 2.005 signal radical and inhibited platelet aggregation induced by AA. PGHS cosubstrates increased the intensity of the radical signal but inhibited platelet aggregation induced by AA. Both S-nitro-L-glutathione and reduced glutathione quenched the g = 2.005 radical but could not restore platelet aggregatory activity. These results suggest that the carbon-centered radical is a self-destructing free radical formed during peroxide-mediated deactivation of PGHS in human platelets.
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Affiliation(s)
- Duen-Suey Chou
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei 110, Taiwan
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17
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Hsiao G, Chang CY, Shen MY, Chou DS, Tzeng SH, Chen TF, Sheu JR. alpha-Naphthoflavone, a potent antiplatelet flavonoid, is mediated through inhibition of phospholipase C activity and stimulation of cyclic GMP formation. J Agric Food Chem 2005; 53:5179-86. [PMID: 15969494 DOI: 10.1021/jf0500738] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The aim of this study was to systematically examine the inhibitory mechanisms of the flavonoid alpha-naphthoflavone (alpha-NF) in platelet activation. In this study, alpha-NF concentration dependently (5-20 microM) inhibited platelet aggregation stimulated by agonists. alpha-NF (5 and 10 microM) inhibited intracellular Ca(2+) mobilization, phosphoinositide breakdown, and thromboxane A(2) formation stimulated by collagen (1 microg/mL) in human platelets. In addition, alpha-NF (5 and 10 microM) markedly increased levels of cyclic GMP and cyclic GMP-induced vasodilator-stimulated phosphoprotein (VASP) Ser(157) phosphorylation. Rapid phosphorylation of a platelet protein of Mr 47,000 (P47), a marker of protein kinase C activation, was triggered by phorbol-12,13-dibutyrate (60 nM). This phosphorylation was markedly inhibited by alpha-NF (5 and 10 microM). However, alpha-NF (5 and 10 microM) did not reduce the electron spin resonance (ESR) signal intensity of hydroxyl radicals in collagen (1 microg/mL)-activated platelets. These results indicate that the antiplatelet activity of alpha-NF may be involved in the following pathways. (1) alpha-NF may inhibit the activation of phospholipase C, followed by inhibition of phosphoinositide breakdown, protein kinase C activation, and thromboxane A(2) formation, thereby leading to inhibition of intracellular Ca(2+) mobilization. (2) alpha-NF also activated the formation of cyclic GMP, resulting in inhibition of platelet aggregation. These results strongly indicate that alpha-NF appears to represent a novel and potent antiplatelet agent for treatment of arterial thromboembolism.
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Affiliation(s)
- George Hsiao
- Graduate Institute of Pharmacology and Graduate Institute of Medical Sciences, Taipei Medical University, Taiwan
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18
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Chou DS, Hsiao G, Shen MY, Fong TH, Lin CH, Chen TF, Sheu JR. Low concentration of oxidized low density lipoprotein suppresses platelet reactivity in vitro: an intracellular study. Lipids 2005; 39:433-40. [PMID: 15506238 DOI: 10.1007/s11745-004-1248-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intracellular mechanisms underlying oxidized low density lipoprotein (oxLDL)-signaling pathways in platelets remain obscure and findings have been controversial. Therefore, we examined the influence of oxLDL in washed human platelets. In this study, oxLDL concentration-dependently (20-100 microg/mL) inhibited platelet aggregation in human platelets stimulated by collagen (1 microg/mL) and arachidonic acid (60 microM), but not by thrombin (0.02 U/mL). The activity of oxLDL was greater at 24 h in inhibiting platelet aggregation than at 12 h. At 24 h, oxLDL concentration-dependently inhibited intracellular Ca2+ mobilization and thromboxane B2 formation in human platelets stimulated by collagen. In addition, at 24 h oxLDL (40 and 80 microg/mL) significantly increased the formation of cyclic AMP, but not cyclic GMP or nitrate. In an ESR study, 24 h-oxLDL (40 microg/mL) markedly reduced the ESR signal intensity of hydroxyl radicals (OH(-)) in both collagen (2 microg/mL)-activated platelets and Fenton reaction (H2O2 + Fe2+). The inhibitory effect of oxLDL may induce radical-radical termination reactions by oxLDL-derived lipid radical interactions with free radicals (such as hydroxyl radicals) released from activated platelets, with a resultant lowering of intracellular Ca2+ mobilization, followed by inhibition of thromboxane A2 formation, thereby leading to increased cyclic AMP formation and finally inhibited platelet aggregation. This study provides new insights concerning the effect of oxLDL in platelet aggregation.
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Affiliation(s)
- Duen-Suey Chou
- Graduate Institutes of Medical Sciences and Pharmacology, Taipei Medical University, Taipei 110, Taiwan
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19
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Hon N, Lynn N, Chen TF. Rectal infiltration by prostatic adenocarcinoma: a report on six patients and review of the literature. Ann R Coll Surg Engl 2005; 87:72-3. [PMID: 15720916 PMCID: PMC1963858 DOI: 10.1308/1478708051261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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20
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Wang CK, Wu YR, Hwu WL, Chen CM, Ro LS, Chen ST, Gwinn-Hardy K, Yang CC, Wu RM, Chen TF, Wang HC, Chao MC, Chiu MJ, Lu CJ, Lee-Chen GJ. DNA haplotype analysis of CAG repeat in Taiwanese Huntington's disease patients. Eur Neurol 2004; 52:96-100. [PMID: 15273431 DOI: 10.1159/000079938] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2003] [Accepted: 05/25/2004] [Indexed: 11/19/2022]
Abstract
We studied the expanded CAG repeat and adjacent CCG repeat in 53 Huntington's disease (HD) patients and 172 unrelated normal subjects matched to the patients for ethnic origin. The range of the CAG repeat varied from 38 to 109 in the HD patients and from 10 to 29 in the control group. A significant negative correlation was found between the age at onset and the CAG expansion, with no significant influence of the adjacent CCG repeat on the age at onset by multiple regression analysis. Allelic association using CCG repeat and 2 flanking dinucleotide repeat markers within 150 kb of the HD gene revealed linkage disequilibrium for 2 of 3 markers. Haplotype analysis of 24 HD families using these markers identified 3 major haplotypes underlying 87.5% of HD chromosomes. The data suggested frequent haplotypes in the Taiwanese population on which one or more mutational events leading to the disease occurred.
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Affiliation(s)
- C K Wang
- Department of Life Science, National Taiwan Normal University, Taipei, Taiwan, ROC
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21
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Hsiao G, Shen MY, Chou DS, Lin CH, Chen TF, Sheu JR. Involvement of the antiplatelet activity of magnesium sulfate in suppression of protein kinase C and the Na+/H+ exchanger. J Biomed Sci 2004; 11:19-26. [PMID: 14730206 DOI: 10.1007/bf02256545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2003] [Accepted: 08/12/2003] [Indexed: 12/01/2022] Open
Abstract
Magnesium sulfate is widely used to prevent seizures in pregnant women with hypertension. The aim of this study was to examine the inhibitory mechanisms of magnesium sulfate in platelet aggregation in vitro. In this study, magnesium sulfate concentration-dependently (0.6-3.0 mM) inhibited platelet aggregation in human platelets stimulated by agonists. Magnesium sulfate (1.5 and 3.0 mM) also concentration-dependently inhibited phosphoinositide breakdown and intracellular Ca+2 mobilization in human platelets stimulated by thrombin. Rapid phosphorylation of a platelet protein of M(r) 47,000 (P47), a marker of protein kinase C activation, was triggered by phorbol-12-13-dibutyrate (PDBu, 50 nM). This phosphorylation was markedly inhibited by magnesium sulfate (3.0 mM). Magnesium sulfate (1.5 and 3.0 mM) further inhibited PDBu-stimulated platelet aggregation in human platelets. The thrombin-evoked increase in pHi was markedly inhibited in the presence of magnesium sulfate (3.0 mM). In conclusion, these results indicate that the antiplatelet activity of magnesium sulfate may be involved in the following two pathways: (1) Magnesium sulfate may inhibit the activation of protein kinase C, followed by inhibition of phosphoinositide breakdown and intracellular Ca+2 mobilization, thereby leading to inhibition of the phosphorylation of P47. (2) On the other hand, magnesium sulfate inhibits the Na+/H+ exchanger, leading to reduced intracellular Ca+2 mobilization, and ultimately to inhibition of platelet aggregation and the ATP-release reaction.
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Affiliation(s)
- George Hsiao
- Graduate Institute of Pharmacology, Taipei Medical University, No. 250 Wu-Hsing Street, Taipei 110, Taiwan
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22
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Hsiao G, Shen MY, Chou DS, Lin CH, Chen TF, Sheu JR. Involvement of the Antiplatelet Activity of Magnesium Sulfate in Suppression of Protein Kinase C and the Na<sup>+</sup>/H<sup>+</sup> Exchanger. J Biomed Sci 2004. [DOI: 10.1159/000075285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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23
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Hsu YH, Hsieh MS, Liang YC, Li CY, Sheu MT, Chou DT, Chen TF, Chen CH. Production of the chemokine eotaxin-1 in osteoarthritis and its role in cartilage degradation. J Cell Biochem 2004; 93:929-39. [PMID: 15389872 DOI: 10.1002/jcb.20239] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The expression of the chemokine, eotaxin-1, and its receptors in normal and osteoarthritic human chondrocytes was examined, and its role in cartilage degradation was elucidated in this study. Results indicated that plasma concentrations of eotaxin-1 as well as the chemokines, RANTES, and MCP-1alpha, were higher in patients with osteoarthritis (OA) than those in normal humans. Stimulation of chondrocytes with IL-1beta or TNF-alpha significantly induced eotaxin-1 expression. The production of eotaxin-1 induced expression of its own receptor of CCR3 and CCR5 on the cell surface of chondrosarcomas, suggesting that an autocrine/paracrine pathway is involved in eotaxin-1's action. In addition, eotaxin-1 markedly increased the expressions of MMP-3 and MMP-13 mRNA, but had no effect on TIMP-1 expression in chondrocytes. However, pretreatment of anti-eotaxin-1 antibody significantly decreased the MMP-3 expression induced by IL-1beta. These results first demonstrate that human chondrocytes express the chemokine, eotaxin-1, and that its expression is induced by treatment with IL-1beta and TNF-alpha. The cytokine-triggered induction of eotaxin-1 further results in enhanced expressions of its own receptor of CCR3, CCR5, and MMPs, suggesting that eotaxin-1 plays an important role in cartilage degradation in OA.
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Affiliation(s)
- Yi-Hsin Hsu
- Department of Internal Medicine, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan, ROC
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24
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Sheu JR, Hsiao G, Shen MY, Chou CY, Lin CH, Chen TF, Chou DS. Inhibitory mechanisms of kinetin, a plant growth-promoting hormone, in platelet aggregation. Platelets 2003; 14:189-96. [PMID: 12850843 DOI: 10.1080/0953710021000060925] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Kinetin has been shown to have anti-aging effects on several different systems including plants and human cells. The aim of this study was to examine the detailed inhibitory mechanisms of kinetin in platelet aggregation. In this study, kinetin concentration-dependently (50-150 microM) inhibited platelet aggregation in human platelets stimulated by agonists. Kinetin (70 and 150 microM) also concentration-dependently inhibited intracellular Ca2+ mobilization and phosphoinositide breakdown in platelets stimulated by collagen (1 microg/ml). Kinetin (70 and 150 microM) significantly inhibited thromboxane A2 formation stimulated by collagen (1 microg/ml) and arachidonic acid (60 microM) in human platelets. In addition, kinetin (70 and 150 microM) significantly increased the formation of cyclic AMP. Intracellular pH values were measured spectrofluorometrically using the fluorescent probe BCECF-AM in platelets. The thrombin-evoked increase in pHi was markedly inhibited in the presence of kinetin (70 and 150 microM). Rapid phosphorylation of a platelet protein of molecular weight (Mr) 47000 (P47), a marker of protein kinase C activation, was triggered by collagen (1 microg/ml). This phosphorylation was inhibited by kinetin (70 and 150 microM). In conclusion, these results indicate that the anti-platelet activity of kinetin may be involved in the following pathways: kinetin's effects may initially be due to inhibition of the activation of phospholipase C and the Na+/H+ exchanger. This leads to lower intracellular Ca2+ mobilization, followed by inhibition of TxA2 formation and then increased cyclic AMP formation, followed by a further inhibition of the Na+/H+ exchanger, ultimately resulting in markedly decreased intracellular Ca2+ mobilization and phosphorylation of P47. These results suggest that kinetin has an effective anti-platelet effect and that it may be a potential therapeutic agent for arterial thrombosis.
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Affiliation(s)
- J R Sheu
- Graduate Institute of Medical Sciences, Taipei Medical University, Taiwan.
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25
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Hsiao G, Shen MY, Fang CL, Chou DS, Lin CH, Chen TF, Sheu JR. Morphine-potentiated platelet aggregation in in vitro and platelet plug formation in in vivo experiments. J Biomed Sci 2003; 10:292-301. [PMID: 12711856 DOI: 10.1007/bf02256448] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2002] [Accepted: 12/20/2002] [Indexed: 10/25/2022] Open
Abstract
The detailed mechanisms underlying morphine-signaling pathways in platelets remain obscure. Therefore, we systematically examined the influence of morphine on washed human platelets. In this study, washed human platelet suspensions were used for in vitro studies. Furthermore, platelet thrombus formation induced by irradiation of mesenteric venules with filtered light in mice pretreated with fluorescein sodium was used for an in vivo thrombotic study. Morphine concentration dependently (0.6, 1, and 5 microM) potentiated platelet aggregation and the ATP release reaction stimulated by agonists (i.e., collagen and U46619) in washed human platelets. Yohimbine (0.1 microM), a specific alpha(2)-adrenoceptor antagonist, markedly abolished the potentiation of morphine in platelet aggregation stimulated by agonists. Morphine also potentiated phosphoinositide breakdown and intracellular Ca(2+) mobilization in human platelets stimulated by collagen (1 microg/ml). Moreover, morphine (0.6-5 microM) markedly inhibited prostaglandin E(1) (10 microM)-induced cyclic AMP formation in human platelets, while yohimbine (0.1 microM) significantly reversed the inhibition of cyclic AMP by morphine (0.6 and 1 microM) in this study. The thrombin-evoked increase in pH(i) was markedly potentiated in the presence of morphine (1 and 5 microM). Morphine (2 and 5 mg/g) significantly shortened the time require to induce platelet plug formation in mesenteric venules. We concluded that morphine may exert its potentiation in platelet aggregation by binding to alpha(2)-adrenoceptors in human platelets, with a resulting inhibition of adenylate cyclase, thereby reducing intracellular cyclic AMP formation followed by increased activation of phospholipase C and the Na(+)/H(+) exchanger. This leads to increased intracellular Ca(2+) mobilization, and finally potentiation of platelet aggregation and of the ATP release reaction.
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Affiliation(s)
- George Hsiao
- Department of Pharmacology, Taipei Medical University, No. 250 Wu-Hsing Street, Taipei 110, Taiwan
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26
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Hsiao G, Shen MY, Chang WC, Cheng YW, Pan SL, Kuo YH, Chen TF, Sheu JR. A novel antioxidant, octyl caffeate, suppression of LPS/IFN-gamma-induced inducible nitric oxide synthase gene expression in rat aortic smooth muscle cells. Biochem Pharmacol 2003; 65:1383-92. [PMID: 12694879 DOI: 10.1016/s0006-2952(03)00070-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In the present study, we investigated the effects and mechanisms of a novel potent antioxidant, octyl caffeate, on the induction of iNOS expression by lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) in cultured primary rat aortic smooth muscle cells (RASMCs) in vitro and LPS-induced hypotension in vivo. Octyl caffeate (0.1-1.0 microM) exerted a concentration-dependent inhibition of iron-catalyzed lipid peroxidation in rat brain homogenates. Furthermore, octyl caffeate (20, 50, and 100 microM) concentration-dependently diminished the initial rate of superoxide-induced NBT reduction and the enzymatic activity of xanthine oxidase. It also concentration-dependently (1-50 microM) inhibited the NO production, iNOS protein and messenger RNA expressions upon stimulation by LPS (100 microg/mL)/IFN-gamma (100U/mL) in RASMCs. In addition, we found that octyl caffeate did not significantly affect IkappaBalpha degradation stimulated by LPS/IFN-gamma in RASMCs. On the other hand, octyl caffeate (10 and 50 microM) significantly suppressed activation of c-Jun-N-terminal kinase and extracellular signal-regulated kinase. Moreover, octyl caffeate (10mg/kg, i.v.) significantly inhibited the fall in mean arterial pressure stimulated by LPS (7.5mg/kg) in rats. In conclusion, we demonstrate that a novel potent antioxidant, octyl caffeate, significantly ameliorates circulatory failure of endotoxemia in vivo by a mechanism involving suppression of iNOS expression through inactivation of mitogen-activated protein kinases in RASMCs.
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Affiliation(s)
- George Hsiao
- Graduate Institute of Medical Sciences and Department of Pharmacology, Taipei Medical University, 250 Wu-Shing Street, Taiwan, ROC
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27
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Hsiao G, Shen MY, Lin KH, Chou CY, Tzu NH, Lin CH, Chou DS, Chen TF, Sheu JR. Inhibitory activity of kinetin on free radical formation of activated platelets in vitro and on thrombus formation in vivo. Eur J Pharmacol 2003; 465:281-7. [PMID: 12681440 DOI: 10.1016/s0014-2999(03)01528-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Kinetin has been shown to have anti-aging effects on several different systems, including plants and human cells. Recently, we demonstrated that kinetin markedly inhibited platelet aggregation in washed human platelets. In the present study, an electron spin resonance (ESR) method was used to further evaluate the scavenging activity of kinetin on the free radicals formed. Kinetin (70 and 150 microM) concentration dependently reduced the ESR signal intensity of hydroxyl radicals in collagen (1 microg/ml)-activated platelets. Furthermore, kinetin was effective in reducing the mortality of ADP-induced acute pulmonary thromboembolism in mice when administered intravenously at doses of 4 and 6 mg/kg. In addition, intravenous injection of kinetin (4 and 6 mg/kg) significantly prolonged the bleeding time by approximately 1.9- and 2.1-fold as compared with normal saline in severed mesenteric arteries of rats. A continuous infusion of kinetin (0.6 mg/kg/min) for 10 min also significantly increased the bleeding time by about 2.3-fold, and the bleeding time returned to baseline within 120 min after cessation of kinetin infusion. Platelet thrombi formation was induced by irradiation of mesenteric venules with filtered light in mice pretreated intravenously with fluorescein sodium. When kinetin was administered at 13 and 14 mg/kg in mice pretreated with fluorescein sodium (5 mg/kg), the occlusion time was significantly prolonged. In conclusion, these results suggest that kinetin has effective free radical-scavenging activity in vitro and antithrombotic activity in vivo. Treatment with kinetin may lower the risk of thromboembolic-related disorders. Therefore, kinetin may be a potential therapeutic agent for arterial thrombosis, but its toxicity must be further assessed.
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Affiliation(s)
- George Hsiao
- Department of Pharmacology, Taipei Medical University, Taipei, Taiwan, ROC
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28
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Chiang LL, Kuo CT, Wang CH, Chen TF, Ho YS, Kuo HP, Lin CH. Involvement of nuclear factor-kappaB in lipoteichoic acid-induced cyclooxygenase-2 expression in RAW 264.7 macrophages. J Pharm Pharmacol 2003; 55:115-23. [PMID: 12625875 DOI: 10.1111/j.2042-7158.2003.tb02441.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have investigated the role of protein kinase C (PKC) and nuclear factor-kappaB (NF-kappaB) in cyclooxygenase-2 (COX-2) expression caused by Staphylococcus aureus lipoteichoic acid in RAW 264.7 macrophages. A phosphatidylcholine-phospholipase C (PC-PLC) inhibitor (D-609) and a phosphatidylinositol-phospholipase C (PI-PLC) inhibitor (U-73122) attenuated lipoteichoic acid-induced COX-2 expression, while a phosphatidate phosphohydrolase inhibitor (propranolol) had no effect. Two PKC inhibitors (Go 6976 and Ro 31-8220) and the NF-kappaB inhibitor, pyrrolidine dithiocarbamate (PDTC), also attenuated lipoteichoic acid-induced COX-2 expression. Lipoteichoic acid resulted in a decrease in PKC activity in the cytosol and an increase in PKC activity in membranes. The lipoteichoic acid-induced translocation of p65 NF-kappaB from the cytosol to the nucleus was inhibited by D-609, U-73122, Go 6976, Ro 31-8220, and PDTC, but not by propranolol. The results suggested that lipoteichoic acid might have activated PC-PLC and PI-PLC to induce PKC activation, which in turn initiated NF-kappaB activation, and finally induced COX-2 expression in RAW 264.7 macrophages.
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Affiliation(s)
- L L Chiang
- School of Respiratory Therapy, Taipei Medical University, Taipei, Taiwan
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Sheu JR, Hsiao G, Lin WY, Chen TF, Chien YY, Lin CH, Tzeng CR. Mechanisms involved in agonist-induced hyperaggregability of platelets from normal pregnancy. J Biomed Sci 2002; 9:17-25. [PMID: 11810021 DOI: 10.1007/bf02256574] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
There is substantial evidence of increased platelet reactivity in vivo and in vitro during pregnancy. Platelet activation occurs in pregnancy with a risk of the development of preeclampsia. In this study, platelet behavior was studied during 28-40 weeks of gestation in a group of women who remained normotensive and a group of nonpregnant female controls. Platelet aggregation and ATP release stimulated by agonists (i.e. collagen and adenosine 5'-diphosphate) were markedly enhanced in washed platelets from pregnant subjects. Furthermore, the collagen-evoked increase in intracellular Ca(2+) ([Ca(2+)](i)) mobilization in fura-2-AM-loaded platelets was also enhanced in pregnant subjects. Moreover, the binding activity of fluorescein isothiocyanate-triflavin toward the platelet glycoprotein IIb/IIIa complex did not significantly differ between the nonpregnant and pregnant groups. In addition, the amount of thromboxane A(2) (TxA(2)) formation from pregnant subjects was significantly greater than that from nonpregnant subjects in both resting and collagen-activated platelets. On the other hand, prostaglandin E(2) formation in the presence of imidazole in either resting or arachidonic acid (100 microM)-treated platelets did not significantly differ between these two groups. The levels of cyclic AMP formation in both resting and prostaglandin E(1) (10 microM)-treated platelets from pregnant subjects were significantly lower than those in nonpregnant subjects. Nitric oxide production was measured by a chemiluminescence detection method in this study. The extent of nitrate production in either resting or collagen-stimulated platelets from pregnant subjects did not significantly differ from that of platelets from the nonpregnant group. We conclude that the agonist-induced hyperaggregability of platelets from normal pregnancy may be due, at least partly, to an increase in TxA(2) formation and a lowering of the level of cyclic AMP formation, which leads to increased [Ca(2+)](i) mobilization and finally to enhanced platelet aggregation and ATP release.
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Affiliation(s)
- Joen-Rong Sheu
- Graduate Institute of Medical Sciences, Department of Pharmacology, Taipei Medical University, Taipei, Taiwan, ROC.
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Wang SL, Lin SY, Chen TF, Chuang CH. Solid-state trans-cis isomerization of captopril determined by thermal Fourier transform infrared (FT-IR) microspectroscopy. J Pharm Sci 2001; 90:1034-9. [PMID: 11536207 DOI: 10.1002/jps.1056] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Thermal Fourier transform infrared (FT-IR) microspectroscopy was used to investigate the conformational isomerization of captopril in the solid state. The result indicates that the IR peak intensity of captopril for original bands decreased dramatically at 102 degrees C, but for new bands it increased with the rise of temperature. The frequency of C=O stretching mode for carboxylic acid and for amide was located at a higher wavenumber of 1747 cm(-1) and at a lower frequency of 1591 cm(-1) as compared with the general compound, suggesting the existence of trans isomer of captopril in the solid state by intramolecular hydrogen bonding. Beyond 102 degrees C, several new bands at 1720, 1645, and 1610 cm(-1) were observed with the rise of temperature, indicating the coexistence of a cis isomer. However, the cis isomer could transform gradually to the trans isomer after cooling. The thermodynamics of equilibrium mixture of cis/trans isomers were also studied. The trans isomer was more stable than the cis isomer, but the cis isomer was favored at the higher temperature.
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Affiliation(s)
- S L Wang
- Biopharmaceutics Laboratory, Department of Medical Research & Education, Veterans General Hospital-Taipei, Shih-Pai, Taipei, Taiwan, Republic of China
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Abstract
[reaction: see text] In the course of natural product synthetic studies, 5-(4-pentenyl)oxazole and 5-(5-hexenyl)oxazole were N-methylated. The initial N-methylated 5-alkenyloxazolium salt adducts were found to be only intermediates and were ultimately transformed into hydroindole and hydroisoquinoline compounds, respectively.
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Affiliation(s)
- D Wenkert
- Department of Chemistry, University of North Texas, Denton, Texas 76203-5068, USA.
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Wang SL, Lin SY, Chen TF. Reaction kinetics of solid-state cyclization of enalapril maleate investigated by isothermal FT-IR microscopic system. Chem Pharm Bull (Tokyo) 2001; 49:402-6. [PMID: 11310665 DOI: 10.1248/cpb.49.402] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To investigate the reaction kinetics of the solid-state degradation process of enalapril maleate, a Fourier transform infrared microspectroscope equipped with thermal analyzer (thermal FT-IR microscopic system) was used. The isothermal stability study was conducted at 120-130 degrees C for 1-2 h and changes in the three-dimensional plots of the IR spectra of enalapril maleate with respect to heating time were observed. The study indicates that the bands at 1649, 1728, and 1751 cm(-1) assigned to intact enalapril maleate gradually reduced in peak intensity with heating time. However, the peak intensities at 1672 and 1738 cm(-1) (due to enalapril diketopiperazine (DKP) formation) and at 3250 cm(-1) (corresponding to water formation) gradually increased with heating time. The solid-state diketopiperazine formation and the degradation process of enalapril maleate via intramolecular cyclization were found to be simultaneous. The isothermal decomposition curves were sigmoidal and were characterized by induction and acceleration periods, indicating the presence of autocatalytic solid-state decompositions. Moreover, the power-law equation (n = 1/4) was found to provide the best fit to the kinetics of decomposition. This isothermal FT-IR microscopic system was easily used to investigate the degradation of enalapril maleate and the concomitant formation of DKP. The solid-state reaction of enalapril maleate required an activation energy of 195+/-12 kJ/mol to undergo the processes of decomposition and intramolecular cyclization.
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Affiliation(s)
- S L Wang
- Department of Medical Research and Education, Veterans General Hospital-Taipei, Taiwan, Republic of China
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Wang SL, Lin SY, Chen TF. Thermal-Dependent dehydration process and intramolecular cyclization of lisinopril dihydrate in the solid state. Chem Pharm Bull (Tokyo) 2000; 48:1890-3. [PMID: 11145138 DOI: 10.1248/cpb.48.1890] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The pathway of dehydration and intramolecular cyclization of lisinopril dihydrate in the solid state was investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and a combination of thermal analyzer with Fourier transform infrared microspectroscopy (thermal FT-IR microscopic system). The results indicate that the dehydration from the solid-state lisinopril dihydrate had a two-step process from dihydrate to monohydrate at 76 degrees C and then from monohydrate to anhydrate at 99-101 approximately C, which could be clearly observed from the above three methods. Only the thermal FT-IR microscopic system could give vital information on diketopiperazine (DKP) formation via intramolecular cyclization in anhydrous lisinopril. A new peak at 1670 cm(-1) assigned to the carbonyl band of DKP formation was clearly evidenced. The water of reaction byproduct was liberated at a temperature >157 degrees C and appeared on the IR spectra near 3200-3400 cm(-1). Moreover, the peak at 1574 cm(-1) assigned to carboxylate shifted to 1552 cm(-1) due to the DKP formation. The peak at 1670 cm(-1) related to the DKP formation changed slightly in intensity from 147 degrees C and significantly near 157 degrees C. DSC and TGA methods were poor for use in supplying information on DKP formation in lisinopril. The thermal FT-IR microscopic system is useful from the view point that it can quickly and directly show the solid-state stability of drug.
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Affiliation(s)
- S L Wang
- Department of Medical Research & Education, Veterans General Hospital-Taipei, Shih-Pai, Republic of China
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Jiang XQ, Jin KY, Chen TF, Li J, Liu JF, Wan ZY. [Treatment of nasofacial hemangioma with interventional embolization and pingyungmycin injection]. Lin Chuang Er Bi Yan Hou Ke Za Zhi 2000; 14:114-5. [PMID: 12541411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To investigate a new method with interventional embolization and pingyugmycin injection for treating nasofacial Hemangioma. METHOD The fillets and coil were used for interventional embolization facial artery, internal maxillary artery, temporal superficial artery, and pingyungmycin injected for 4 patients. RESULT The tumor and vascular beat in this series of 4 patients were disappeared by follow up of one year. There are not nasal obstruction and epistaxis. CONCLUSION Treatment with interventional embolization and pingyungmycin injection is a safe and effective method for nasofacial hemangioma.
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Affiliation(s)
- X Q Jiang
- Department of Otorhinolaryngology, Second Affiliated Hospital, Hubei Medical University, Wuhan 430071
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Lai LP, Lin JL, Chen TF, Ko WC, Lien WP. Clinical, electrophysiological characteristics, and radiofrequency catheter ablation of atrial tachycardia near the apex of Koch's triangle. Pacing Clin Electrophysiol 1998; 21:367-74. [PMID: 9507537 DOI: 10.1111/j.1540-8159.1998.tb00060.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Atrial tachycardia, with its focus near the apex of Koch's triangle, may carry a potential risk of atrioventricular block during radiofrequency catheter ablation. The efficacy and safety of this procedure have never been addressed. The characteristics and catheter ablation results are reported for six patients with atrial tachycardia near the apex of Koch's triangle. All six patients were female aged 49.6 +/- 9.3 years (range 39-63). Organic heart disease was present in 3 (50%) of the 6 patients. The P wave in surface ECG had a mean axis of -28 degrees (range -90 degrees - +30 degrees) in the frontal plane. The catheter ablation was guided by activation sequence mapping. The energy was titrated from low power level. Atrial overdrive pacing was used to monitor the atrioventricular conduction should accelerated junctional rhythm occur. At the final successful ablation site, the local atrial activation was 41.8 +/- 9.1 ms before the P wave and His-bundle potential was present in 5 of the 6 patients. All patients had their atrial tachycardia eliminated without recurrence or heart block during a follow-up period of 17.7 +/- 8.5 months (range 6-30). In conclusion, atrial tachycardia near the apex of Koch's triangle has distinct clinical and electrophysiological features. Radiofrequency catheter ablation can be performed effectively. However, extreme care must be taken to prevent inadvertent atrioventricular block. Titrated energy application and continuous monitoring of atrioventricular conduction are mandatory.
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Affiliation(s)
- L P Lai
- Department of Internal Medicine, National Taiwan University Hospital
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Abstract
In this study, we explored the possible mechanism of cooling-induced relaxation of the isolated guinea-pig trachea. A rapid cooling (-4 degrees C/min) from 37 +/- 0.5 degree C to 25 +/- 0.5 degree C induced a transient and small contraction followed by a sustained cooling-relaxation. This relaxation was not blocked by propranolol or tetrodotoxin. Various concentrations of four contractile agonists (histamine, carbachol, 5-HT and ryanodine) all enhanced cooling-relaxation in a concentration-dependent manner which correlated well with their increase in the developed muscular tension, suggesting an inherent counterbalance between cooling-relaxation and the bronchoconstriction. Treating with either indomethacin or nordihydroguaiaretic acid (NDGA) did not affect the contractile properties of histamine, carbachol and 5-HT except ryanodine, but reversed cooling-relaxation into sustained cooling-contraction. Indomethacin partially inhibited but NDGA abolished cooling-relaxation induced by ryanodine. Moreover, ryanodine, but not the other three contractile agonists, could antagonize indomethacin in inducing cooling-contractions by various agonists. From above findings, we can conclude that eicosanoids including prostaglandins particularly leukotrienes, which would be produced by the elevated Ca(2+)-release from the ryanodine sensitive Ca(2+)-store, play prominent roles in inducing cooling-relaxation.
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Affiliation(s)
- D S Chou
- Department of Pharmacology, Taipei Medical College, Taiwan
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Abstract
The contribution of organic and psychogenic factors in the aetiopathogenesis of impotence was studied in a large number of diabetic males, to develop an algorithm for its management. We examined 110 consecutive patients who were referred to the Impotence Clinic of the Diabetes Centre. All patients were initially evaluated by a diabetologist and then underwent psychosexual assessment by a specialized psychiatrist. Patients with primarily organic disease were referred to a urologist for further management while those with psychogenic impotence received psychosexual counselling. Peripheral neuropathy was present in 71 (65%) and two or more autonomic tests were abnormal in 22 (20%) patients. Neuropathy was the only cause detected in 29 (27%) patients, the main cause in 22 (20%), and contributing, but not the main factor, in 20 (18%). Psychogenic factors were the only cause detected in 12 (11%) patients, the main cause in 26 (24%) and contributed in 19 (17%). Marital disharmony, medical treatment, and peripheral vascular disease were the main aetiopathogenic factors in the remaining cases. Psychosexual counselling resulted in successful intercourse in 17 (60%) out of the 24 treated patients and papaverine injections in 31 (61%) out of 56 treated patients. It is concluded that although organic factors are mainly responsible for the development of impotence in diabetic males, psychological factors contribute significantly and psychosexual assessment and counselling are essential adjuncts to its management. Treatment with papaverine injections is generally inexpensive and effective to overcome the multifactorial causes of erectile dysfunction in this population. An algorithm which may facilitate the investigation and treatment of impotent diabetic males is proposed.
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Affiliation(s)
- A Veves
- University Department of Medicine, Manchester Royal Infirmary, UK
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Chen TF, Clarke N, Bowman R, Harper NJ, Payne SR. Intermuscular bupivacaine infusion for control of pain after renal surgery: a preliminary report. Br J Urol 1994; 74:155-9. [PMID: 7921931 DOI: 10.1111/j.1464-410x.1994.tb16578.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE To assess the value of continuous bupivacaine wound infusion for post-operative pain relief after renal surgery. PATIENTS AND METHODS The analgesic efficacy of continuous intermuscular wound infusion with 0.25% bupivacaine was studied in 10 patients (four men, six women), with a mean age of 47.5 years (range 25-71) and a mean weight of 71.2 kg (range 44-99), after renal surgery in a single-blind randomized trial. The results were compared with those of an age- and weight-matched control group of 10 patients (five men, five women) with a mean age of 47.7 years (range 27-73) and a mean weight of 67.3 kg (range 51-85). Post-operative pain was studied objectively by assessing individual patient's morphine requirements administered via a patient controlled analgesia system, and subjectively with pain scores. Patient mobility was assessed by ward nursing staff using mobility score charts. RESULTS There was a lower demand for post-operative analgesia in the bupivacaine group compared with the control. Although there was no significant difference in the pain scores between the two groups, the bupivacaine group was significantly more mobile than the control group after surgery. There was no significant difference in the mean post-operative hospital stay between the two groups. CONCLUSION Continuous intermuscular bupivacaine wound infusion is a simple and safe procedure which lowers the patients' post-operative analgesic requirements, allows for earlier mobility and may promote more rapid discharge from hospital.
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Affiliation(s)
- T F Chen
- Department of Urology, Manchester Royal Infirmary, UK
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Chen TF, Collier DS. Intraperitoneal rupture of an infected urachus. Br J Urol 1994; 74:134-5. [PMID: 8044521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Chen TF, Robinson E, Payne SR, Robinson E. A district urinary catheter policy. Why have one? Ann R Coll Surg Engl 1994; 76:190-3. [PMID: 8017814 PMCID: PMC2502286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
A catheter audit was performed at the Central Manchester Trust, which found that there was excessive ordering, inappropriate catheter selection by size, materials, balloon size and poor guidelines on catheter storage. From these findings and from the available literature, we have proposed guidelines on catheter selection with the aim of offering the best patient care and to provide cost efficiency which may be of benefit to other hospitals.
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Affiliation(s)
- T F Chen
- Department of Urological Surgery, Manchester Royal Infirmary
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Abstract
OBJECTIVE To investigate the effects of gamma-amino-butyric acid (GABA) on detrusor activity in man to determine whether it has any inhibitory effect on detrusor contraction. The inhibitory neurotransmitter GABA has been found in mammalian urinary bladders and the effects of GABA on detrusor activity in the rabbit bladder has previously been described [1]. MATERIALS AND METHODS Human detrusor muscle strips, obtained at cystectomy, were made to contract by electrical stimulation of their autonomic nerves or by the addition of carbachol in a superfusion apparatus. GABA and its analogues were added to the superfusion chamber and any changes in the responses were measured. RESULTS The electrically evoked nerve-mediated contractions in human bladder muscle were exclusively cholinergic. GABA inhibited nerve-mediated contractions in human detrusor muscle-strips by the activation of the GABAB receptor, since baclofen (a GABAB receptor agonist) produced similar inhibition and muscimol (a GABAA receptor agonist) did not. There was no inhibition of carbachol-mediated contractions by GABA. CONCLUSION This in vitro study shows that GABA has a peripherally mediated inhibitory effect on excitatory neurotransmission in human detrusor muscle. The site of action is on the post-ganglionic nerves and appears to be mediated via the GABAB receptor.
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Affiliation(s)
- T F Chen
- Department of Urology, Addenbrooke's Hospital, Cambridge, UK
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Chen TF, Eardley I, Doyle PT, Bullock KN. Rectal obstruction secondary to carcinoma of the prostate treated by transanal resection of the prostate. Br J Urol 1992; 70:643-7. [PMID: 1283104 DOI: 10.1111/j.1464-410x.1992.tb15835.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Rectal obstruction caused by carcinoma of the prostate is uncommon. If the disease does not respond to either hormonal treatment or radiotherapy, the only surgical means of relieving the obstruction has been the formation of a colostomy. We present an alternative treatment, since many of these patients are elderly with a short life expectancy and they may have difficulty coping with a stoma. Seven transanal endoscopic resections of the prostate (TARP) have been performed on 5 patients. The procedure is not without complications, but it does offer simple surgical palliation of the rectal obstruction and obviates the need for a colostomy.
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Affiliation(s)
- T F Chen
- Department of Urology, Addenbrooke's Hospital, Cambridge
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Affiliation(s)
- T F Chen
- Department of Urology, Addenbrooke's Hospital, Cambridge
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Chen TF, Yu H, Barofsky DF. Centrifugal size-exclusion chromatographic method for rapid desalting and filtering of carbohydrate samples prior to fast atom bombardment mass spectrometry. Anal Chem 1992; 64:2014-9. [PMID: 1384389 DOI: 10.1021/ac00041a046] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- T F Chen
- Department of Agricultural Chemistry, Oregon State University Corvallis 97331
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Abstract
Gamma-amino-butyric acid (GABA) is an established inhibitory neurotransmitter in the central nervous system (CNS) and it has also been identified in the bladder. We have investigated in the rabbit the effect of GABA on detrusor activity. Rabbit detrusor muscle strips were made to contract by electrical stimulation of their autonomic nerves or by the addition of carbachol. The addition of GABA caused substantial inhibition of muscle contraction. GABA acts on 2 classes of receptors-GABAA and GABAB. The inhibition was mediated via the GABAB receptors as its effect was mimicked by baclofen (a GABAB agonist) and inhibited by 2-hydroxysaclofen (a GABAB receptor antagonist). Inhibition was not prevented by bicuculline (a GABAA receptor antagonist). This inhibition may be due to a direct muscle effect since the inhibition, which occurred with carbachol-induced contraction, was not abolished by the addition of tetrodotoxin. GABA, acting via the GABAB receptor, produces substantial inhibition of muscle contraction in the rabbit urinary bladder. This raises the possibility of using GABAB analogues in the treatment of detrusor instability.
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Affiliation(s)
- T F Chen
- Department of Urology, Addenbrooke's Hospital, Cambridge
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Abstract
Fifteen epididymectomies were performed on 10 patients with post-vasectomy pain and 12 specimens were available for histopathological review. The findings were compared with those in 2 groups in which epididymectomy was performed for chronic epididymo-orchitis and epididymal cysts. The results showed that 50% of the post-vasectomy group were cured by simple epididymectomy. Pathological findings revealed features of long-standing obstruction and interstitial and perineural fibrosis which may have accounted for the pain. It is important to recognise this late complication of vasectomy and, if surgery is to be performed, to include all of the distal vas and previous vasectomy site in the excision.
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Affiliation(s)
- T F Chen
- Department of Urology, Addenbrooke's Hospital, Cambridge
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Chen TF, Collier DS. Intraperitoneal rupture of an infected urachal cyst in an infant. Case report. Eur J Surg 1991; 157:67-8. [PMID: 1675885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Peritonitis due to intraperitoneal rupture of an infected urachal cyst is a life-threatening condition, not previously reported in an infant. We report this condition in an 8-month-old infant. The child underwent complete excision of the urachal remnant and made an uneventful recovery; bacterial culture grew Staphylococcus aureus. Subsequent investigations did not reveal any other renal tract abnormalities.
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Affiliation(s)
- T F Chen
- Department of Surgery, Addenbrooke's Hospital, Cambridge, England
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Chen TF, Collier DS, Everett WG, Freeman AH. Occult blood loss from small bowel tumours. Case report. Acta Chir Scand 1990; 156:499-501. [PMID: 2368555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We report 4 patients who presented with occult blood loss, from a small bowel adenocarcinoma, in whom there was considerable delay in diagnosis. The difficulty in diagnosis and the role of CT scanning is discussed. We recommend a careful laparotomy when endoscopic and radiological investigations fail to reveal the source of blood loss.
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Affiliation(s)
- T F Chen
- Department of Surgery, Addenbrooke's Hospital, Cambridge, England
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Abstract
Benign neoplasms of the trachea are rare. We describe a 46-year-old patient with a lipoma arising from the membranous trachea and causing severe respiratory obstruction. Investigation and management of this problem are discussed, and the literature is reviewed.
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Affiliation(s)
- T F Chen
- Department of Cardiothoracic Surgery, Papworth Hospital, Cambridge, England
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