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Chakladar J, Diomino A, Li WT, Tsai JC, Krishnan AR, Zou AE, Kharidia K, Baig FA, Householder S, Kuo SZ, Chandrasekar S, Chang EY, Ongkeko WM. Medical student's perception of the COVID-19 pandemic effect on their education and well-being: a cross-sectional survey in the United States. BMC Med Educ 2022; 22:149. [PMID: 35248030 PMCID: PMC8897763 DOI: 10.1186/s12909-022-03197-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 02/14/2022] [Indexed: 05/16/2023]
Abstract
BACKGROUND The effects of drastic curricular changes necessitated by the COVID-19 pandemic on medical students' education and wellbeing have remained largely unstudied. Out study aimed to characterize how medical students were affected by the pandemic, specifically how limitations introduced by the pandemic may have affected the quality, delivery, and experience of medical education. METHODS Three hundred students from 5 U.S. allopathic medical schools were surveyed to determine students' perceptions about their quality of medical education, professional development, and mental health during the COVID-19 pandemic (October 2020-December 2020). RESULTS A large majority of students report that while lecture-based learning has not been significantly affected by the pandemic, small-group and clinical learning have greatly declined in quality. Students also reported higher levels of depression, anxiety, and uncertainty with regards to their futures as physicians. CONCLUSIONS The COVID-19 pandemic has greatly affected the medical student education and wellbeing. Although medical schools have implemented measures to continue to train medical students as effectively as they can, further strategies must be devised to ensure the well-being of students in the present and for future national emergencies.
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Affiliation(s)
- Jaideep Chakladar
- Division of Otolaryngology-Head and Neck Surgery, Department Surgery, University of California, La Jolla, San Diego, California, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Anthony Diomino
- UC San Diego School of Medicine, University of California, San Diego, CA, 92093, USA
| | - Wei Tse Li
- Division of Otolaryngology-Head and Neck Surgery, Department Surgery, University of California, La Jolla, San Diego, California, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Joseph C Tsai
- Division of Otolaryngology-Head and Neck Surgery, Department Surgery, University of California, La Jolla, San Diego, California, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | | | - Angela E Zou
- Harvard Medical School, Harvard University, Boston, MA, 02115, USA
| | - Khush Kharidia
- Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Farhan A Baig
- University of Missouri-Kansas City School of Medicine, Kansas City, MO, 64110, USA
| | - Sarah Householder
- Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
| | - Selena Z Kuo
- Department of Internal Medicine, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, 10032, USA
| | - Shyam Chandrasekar
- Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Eric Y Chang
- Department of Radiology, University of California, San Diego, CA, 92093, USA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Weg M Ongkeko
- Division of Otolaryngology-Head and Neck Surgery, Department Surgery, University of California, La Jolla, San Diego, California, USA.
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA.
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Wong LM, Li WT, Shende N, Tsai JC, Ma J, Chakladar J, Gnanasekar A, Qu Y, Dereschuk K, Wang-Rodriguez J, Ongkeko WM. Analysis of the immune landscape in virus-induced cancers using a novel integrative mechanism discovery approach. Comput Struct Biotechnol J 2021; 19:6240-6254. [PMID: 34900135 PMCID: PMC8636736 DOI: 10.1016/j.csbj.2021.11.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 11/11/2021] [Accepted: 11/11/2021] [Indexed: 11/17/2022] Open
Abstract
Background The mechanisms of carcinogenesis from viral infections are extraordinarily complex and not well understood. Traditional methods of analyzing RNA-sequencing data may not be sufficient for unraveling complicated interactions between viruses and host cells. Using RNA and DNA-sequencing data from The Cancer Genome Atlas (TCGA), we aim to explore whether virus-induced tumors exhibit similar immune-associated (IA) dysregulations using a new algorithm we developed that focuses on the most important biological mechanisms involved in virus-induced cancers. Differential expression, survival correlation, and clinical variable correlations were used to identify the most clinically relevant IA genes dysregulated in 5 virus-induced cancers (HPV-induced head and neck squamous cell carcinoma, HPV-induced cervical cancer, EBV-induced stomach cancer, HBV-induced liver cancer, and HCV-induced liver cancer) after which a mechanistic approach was adopted to identify pathways implicated in IA gene dysregulation. Results Our results revealed that IA dysregulations vary with the cancer type and the virus type, but cytokine signaling pathways are dysregulated in all virus-induced cancers. Furthermore, we also found that important similarities exist between all 5 virus-induced cancers in dysregulated clinically relevant oncogenic signatures and IA pathways. Finally, we also discovered potential mechanisms for genomic alterations to induce IA gene dysregulations using our algorithm. Conclusions Our study offers a new approach to mechanism identification through integrating functional annotations and large-scale sequencing data, which may be invaluable to the discovery of new immunotherapy targets for virus-induced cancers.
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Key Words
- Algorithm
- C2, Canonical pathway
- C6, Oncogenic signature
- C7, Immunological signature
- CA, Cancer-associated
- CESC, Cervical Squamous Cell Carcinoma and Endocervical Adenocarcinoma
- CNA, Copy number alteration
- Cervical squamous cell carcinoma and endocervical adenocarcinoma
- EBV, Epstein-Barr virus
- Epstein-Barr virus
- FDR, False discovery rate
- GSEA, Gene set enrichment analysis
- HBV, Hepatitis B virus
- HCV, Hepatitis C virus
- HNSCC, Head and Neck Squamous Cell Carcinoma
- HPV, Human papillomavirus
- Head and neck squamous cell carcinoma
- Hepatitis B
- Hepatitis C
- Human papillomavirus
- IA, Immune-associated
- LIHC, Liver Hepatocellular Carcinoma
- Liver hepatocellular carcinoma
- MSigDB, Molecular Signature Database
- STAD, Stomach Adenocarcinoma
- Stomach adenocarcinoma
- TCGA
- TCGA, The Cancer Genome Atlas
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Affiliation(s)
- Lindsay M. Wong
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Wei Tse Li
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Neil Shende
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Joseph C. Tsai
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Jiayan Ma
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Jaideep Chakladar
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Aditi Gnanasekar
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Yuanhao Qu
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Kypros Dereschuk
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Jessica Wang-Rodriguez
- Department of Pathology, University of California San Diego, La Jolla, CA 92093, USA
- Pathology Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Weg M. Ongkeko
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
- Corresponding author at: Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of California, San Diego, La Jolla, CA 92093, USA.
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Tsai JC, Saad OA, Magesh S, Xu J, Lee AC, Li WT, Chakladar J, Fuster MM, Chang EY, Wang-Rodriguez J, Ongkeko WM. Tobacco Smoke and Electronic Cigarette Vapor Alter Enhancer RNA Expression That Can Regulate the Pathogenesis of Lung Squamous Cell Carcinoma. Cancers (Basel) 2021; 13:cancers13164225. [PMID: 34439379 PMCID: PMC8391195 DOI: 10.3390/cancers13164225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 08/20/2021] [Accepted: 08/20/2021] [Indexed: 12/29/2022] Open
Abstract
Simple Summary It is well established that tobacco smoke is the key player in lung squamous cell carcinoma (LUSC) pathogenesis, and there is growing evidence that electronic cigarette (e-cigarette) vapor may also cause LUSC. Recently, several studies have associated tobacco smoke with differential enhancer RNA (eRNA) expression. However, the effects of tobacco smoke and e-cigarette vapor on eRNA expression in correlation to LUSC outcomes have not been fully elucidated. This study demonstrates that tobacco smoke and e-cigarette vapor may decrease DNA methylation and increase chromosomal alterations at key sites, which ultimately upregulate the expression of oncogenic eRNAs and downregulate the expression of tumor-suppressing eRNAs. Subsequently, we demonstrate that these eRNAs may have altered interactions with immune cells to promote LUSC pathogenesis and reduced patient survival. We hope our results can be validated in future studies, and the key eRNAs we identified may be used as effective targets for more specialized treatments for smoking-mediated LUSC. Abstract Tobacco is the primary etiologic agent in worsened lung squamous cell carcinoma (LUSC) outcomes. Meanwhile, it has been shown that etiologic agents alter enhancer RNAs (eRNAs) expression. Therefore, we aimed to identify the effects of tobacco and electronic cigarette (e-cigarette) use on eRNA expression in relation to LUSC outcomes. We extracted eRNA counts from RNA-sequencing data of tumor/adjacent normal tissue and before/after e-cigarette tissue from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO), respectively. Tobacco-mediated LUSC eRNAs were correlated to patient survival, clinical variables, and immune-associated elements. eRNA expression was also correlated to mutation rates through the Repeated Evaluation of Variables Conditional Entropy and Redundance (REVEALER) algorithm and methylated sites through methylationArrayAnalysis. Differential expression analysis was then completed for the e-cigarette data to compare with key tobacco-mediated eRNAs. We identified 684 downregulated eRNAs and 819 upregulated eRNAs associated with tobacco-mediated LUSC, specifically, with the cancer pathological stage. We also observed a decrease in immune cell abundance in tobacco-mediated LUSC. Yet, we found an increased association of eRNA expression with immune cell abundance in tobacco-mediated LUSC. We identified 16 key eRNAs with significant correlations to 8 clinical variables, implicating these eRNAs in LUSC malignancy. Furthermore, we observed that these 16 eRNAs were highly associated with chromosomal alterations and reduced CpG site methylation. Finally, we observed large eRNA expression upregulation with e-cigarette use, which corresponded to the upregulation of the 16 key eRNAs. Our findings provide a novel mechanism by which tobacco and e-cigarette smoke influences eRNA interactions to promote LUSC pathogenesis and provide insight regarding disease progression at a molecular level.
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Affiliation(s)
- Joseph C. Tsai
- Department of Surgery, Division of Otolaryngology—Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA 92093, USA; (J.C.T.); (O.A.S.); (S.M.); (J.X.); (A.C.L.); (W.T.L.); (J.C.)
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Omar A. Saad
- Department of Surgery, Division of Otolaryngology—Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA 92093, USA; (J.C.T.); (O.A.S.); (S.M.); (J.X.); (A.C.L.); (W.T.L.); (J.C.)
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Shruti Magesh
- Department of Surgery, Division of Otolaryngology—Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA 92093, USA; (J.C.T.); (O.A.S.); (S.M.); (J.X.); (A.C.L.); (W.T.L.); (J.C.)
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Jingyue Xu
- Department of Surgery, Division of Otolaryngology—Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA 92093, USA; (J.C.T.); (O.A.S.); (S.M.); (J.X.); (A.C.L.); (W.T.L.); (J.C.)
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Abby C. Lee
- Department of Surgery, Division of Otolaryngology—Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA 92093, USA; (J.C.T.); (O.A.S.); (S.M.); (J.X.); (A.C.L.); (W.T.L.); (J.C.)
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Wei Tse Li
- Department of Surgery, Division of Otolaryngology—Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA 92093, USA; (J.C.T.); (O.A.S.); (S.M.); (J.X.); (A.C.L.); (W.T.L.); (J.C.)
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Jaideep Chakladar
- Department of Surgery, Division of Otolaryngology—Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA 92093, USA; (J.C.T.); (O.A.S.); (S.M.); (J.X.); (A.C.L.); (W.T.L.); (J.C.)
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Mark M. Fuster
- VA San Diego Healthcare System, Medical and Research Sections, La Jolla, San Diego, CA 92161, USA;
- Department of Medicine, Division of Pulmonary and Critical Care, University of California, La Jolla, San Diego, CA 92037, USA
| | - Eric Y. Chang
- Department of Radiology, University of California, San Diego, CA 92093, USA;
- Radiology Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Jessica Wang-Rodriguez
- Department of Pathology, UC San Diego School of Medicine, San Diego, CA 92093, USA;
- Pathology Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
| | - Weg M. Ongkeko
- Department of Surgery, Division of Otolaryngology—Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA 92093, USA; (J.C.T.); (O.A.S.); (S.M.); (J.X.); (A.C.L.); (W.T.L.); (J.C.)
- Research Service, VA San Diego Healthcare System, San Diego, CA 92161, USA
- Correspondence: ; Tel.: +1-(858)-552-8585-X-7165
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Li WT, Ma J, Shende N, Castaneda G, Chakladar J, Tsai JC, Apostol L, Honda CO, Xu J, Wong LM, Zhang T, Lee A, Gnanasekar A, Honda TK, Kuo SZ, Yu MA, Chang EY, Rajasekaran MR, Ongkeko WM. Using machine learning of clinical data to diagnose COVID-19: a systematic review and meta-analysis. BMC Med Inform Decis Mak 2020; 20:247. [PMID: 32993652 PMCID: PMC7522928 DOI: 10.1186/s12911-020-01266-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 09/16/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The recent Coronavirus Disease 2019 (COVID-19) pandemic has placed severe stress on healthcare systems worldwide, which is amplified by the critical shortage of COVID-19 tests. METHODS In this study, we propose to generate a more accurate diagnosis model of COVID-19 based on patient symptoms and routine test results by applying machine learning to reanalyzing COVID-19 data from 151 published studies. We aim to investigate correlations between clinical variables, cluster COVID-19 patients into subtypes, and generate a computational classification model for discriminating between COVID-19 patients and influenza patients based on clinical variables alone. RESULTS We discovered several novel associations between clinical variables, including correlations between being male and having higher levels of serum lymphocytes and neutrophils. We found that COVID-19 patients could be clustered into subtypes based on serum levels of immune cells, gender, and reported symptoms. Finally, we trained an XGBoost model to achieve a sensitivity of 92.5% and a specificity of 97.9% in discriminating COVID-19 patients from influenza patients. CONCLUSIONS We demonstrated that computational methods trained on large clinical datasets could yield ever more accurate COVID-19 diagnostic models to mitigate the impact of lack of testing. We also presented previously unknown COVID-19 clinical variable correlations and clinical subgroups.
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Affiliation(s)
- Wei Tse Li
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Jiayan Ma
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Neil Shende
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Grant Castaneda
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Jaideep Chakladar
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Joseph C Tsai
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Lauren Apostol
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Christine O Honda
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Jingyue Xu
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Lindsay M Wong
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Tianyi Zhang
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Abby Lee
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Aditi Gnanasekar
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Thomas K Honda
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Selena Z Kuo
- Department of Medicine, Columbia University Medical Center, New York, NY, 10032, USA
| | - Michael Andrew Yu
- Department of Internal Medicine, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Eric Y Chang
- Department of Radiology, University of California San Diego, San Diego, CA, 92093, USA
- Radiology Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Mahadevan Raj Rajasekaran
- Department of Urology, University of California San Diego, San Diego, CA, 92093, USA
- Urology Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA
| | - Weg M Ongkeko
- Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, UC San Diego School of Medicine, San Diego, CA, 92093, USA.
- Research Service, VA San Diego Healthcare System, San Diego, CA, 92161, USA.
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Chakladar J, Chu M, Gnanasekar A, Rosenberg KF, Tsai JC, Wong LM, Ongkeko WM. Abstract 4234: Computational analysis of immune-associated genomic and transcriptomic elements differentiating papillary thyroid cancer subtypes. Cancer Res 2019. [DOI: 10.1158/1538-7445.am2019-4234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Approximately 600,000 patients live with papillary thyroid cancer (PTC) in the United States, with its incidence rising from 4.8 to 14.9 cases per 100,000 people from 1975 to 2012. Despite being the fastest growing cancer, the therapeutic options for PTC has remained unchanged and are primarily limited to surgery, radioactive iodine, and chemotherapy. Considering the untapped potential of immunotherapy for thyroid cancer, this study explores the genomic and transcriptomic features of PTC subtypes in order to identify dysregulated immune-associated (IA) genes and IA pathways that may serve as therapeutic targets. Using data from The Cancer Genome Atlas (TCGA), the three most common histological subtypes of PTC, including the classical (CPTC), the follicular variant (FVPTC), and the tall cell (TCPTC), were analyzed computationally and compared to normal tissue to identify differentially expressed IA genes. These dysregulated IA genes were further filtered for prognostic significance using MACIS scores. To investigate the molecular mechanism for their dysregulation and explore the possibility of genome-based patient stratification, we profiled the correlation of genomic alterations, including mutation and copy number variation, in the various PTC subtypes to IA gene expression using the information theory-based algorithm REVEALER. Our analyses revealed that the expression profiles of CPTC and TCPTC were the most similar from an immunological perspective, with 360 IA genes similarly dysregulated in both of those subtypes. Additionally, TCPTC had the most unique immunological profile, with 300 IA genes dysregulated exclusively in TCPTC, compared to 107 in FVPTC and 22 in CPTC. Specifically, gene such as RAET1E, FGFR11, and MUC1, which are associated with innate and adaptive immune responses, cell survival and proliferation, and TP53-transcription respectively, were dysregulated only in TCPTC. We also studied gene expression regulators and determined that microRNAs had a limited role in the gene dysregulation we observed. However, the regulatory pathways and mutational features unique to certain subtypes were indicative of pathways differentiating cancer prognosis between PTC subtypes. Most notably, genes in the glycosylation pathway mediated by MUC1 and B3GNT3 are upregulated in TCPTC but are downregulated in the less aggressive FVPTC and CPTC subtypes, suggesting a possible mechanism for the aggressive progression of TCPTC. In summary, our findings indicate that subtypes of PTC have both common and unique dysregulated IA genes and pathways, which may be exploited to develop novel immunotherapy targets or biomarkers predictive of prognosis for the different subtypes.
Citation Format: Jaideep Chakladar, Megan Chu, Aditi Gnanasekar, Kristen F. Rosenberg, Joseph C. Tsai, Lindsay M. Wong, Weg M. Ongkeko. Computational analysis of immune-associated genomic and transcriptomic elements differentiating papillary thyroid cancer subtypes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4234.
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Tsai JC, Wang CT, Chen KT. X-Ray Quiz: A 32-Year-Old Female with Abdominal Pain. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791702400211] [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: 11/16/2022] Open
Affiliation(s)
| | | | - KT Chen
- Taipei Medical University, Department of Emergency Medicine, Taipei, Taiwan
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Chu CY, Jiang X, Jinnai H, Pei RY, Lin WF, Tsai JC, Chen HL. Correction: Real-space evidence of the equilibrium ordered bicontinuous double diamond structure of a diblock copolymer. Soft Matter 2015; 11:4142. [PMID: 25939696 DOI: 10.1039/c5sm90077h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Correction for 'Real-space evidence of the equilibrium ordered bicontinuous double diamond structure of a diblock copolymer' by C. Y. Chu et al., Soft Matter, 2015, 11, 1871-1876.
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Affiliation(s)
- C Y Chu
- Department of Chemical Engineering, Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsin-Chu 30013, Taiwan.
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Chu CY, Jiang X, Jinnai H, Pei RY, Lin WF, Tsai JC, Chen HL. Real-space evidence of the equilibrium ordered bicontinuous double diamond structure of a diblock copolymer. Soft Matter 2015; 11:1871-1876. [PMID: 25635830 DOI: 10.1039/c4sm02608j] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The ordered bicontinuous double diamond (OBDD) structure has long been believed to be an unstable ordered network nanostructure, which is relative to the ordered bicontinuous double gyroid (OBDG) structure for diblock copolymers. Using electron tomography, we present the first real-space observation of the thermodynamically stable OBDD structure in a diblock copolymer composed of a stereoregular block, syndiotactic polypropylene-block-polystyrene (sPP-b-PS), in which the sPP tetrapods are interconnected via a bicontinuous network with Pn3̄m symmetry. The OBDD structure underwent a thermally reversible order-order transition (OOT) to OBDG upon heating, and the transition was accompanied with a slight reduction of domain spacing, as demonstrated both experimentally and theoretically. The thermodynamic stability of the OBDD structure was attributed to the ability of the configurationally regular sPP block to form helical segments, even above its melting point, as the reduction of internal energy associated with the helix formation may effectively compensate the greater packing frustration in OBDD relative to that in the tripods of OBDG.
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Affiliation(s)
- C Y Chu
- Department of Chemical Engineering, Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsin-Chu 30013, Taiwan.
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Tsai JC, Chang SM, Yen SH, Li KC, Chen YH, Shih TK. A real-time hand gesture recognition system for daily information retrieval from the internet. IJCSE 2015. [DOI: 10.1504/ijcse.2015.071875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Tsai JC, Chang SM, Yen SH, Shih TK, Li KC. 3D skeleton construction by multi-view 2D images and 3D model segmentation. IJCSE 2015. [DOI: 10.1504/ijcse.2015.070988] [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: 11/21/2022]
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11
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Chang SM, Tsai JC, Yen SH, Shih TK. Constructing interactive multi-view videos based on image-based rendering. IJCSE 2015. [DOI: 10.1504/ijcse.2015.070996] [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: 11/21/2022]
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12
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13
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Tseng SP, Teng LJ, Chen CT, Lo TH, Hung WC, Chen HJ, Hsueh PR, Tsai JC. Toluidine blue O photodynamic inactivation on multidrug-resistant Pseudomonas aeruginosa. Lasers Surg Med 2009; 41:391-7. [PMID: 19533759 DOI: 10.1002/lsm.20765] [Citation(s) in RCA: 44] [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] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND AND OBJECTIVES Multidrug-resistant (MDR) Pseudomonas aeruginosa infection is becoming a critical problem worldwide. Currently, only limited therapeutic options are available for the treatment of infections caused by MDR P. aeruginosa, therefore, the development of new alternative treatments is needed. Toluidine blue O (TBO) is an effective antibacterial photosensitizing agent against various bacteria. However, reports on antibacterial photosensitization of MDR bacteria are limited. This study aims to determine the in vitro photobactericidal activity of TBO against MDR P. aeruginosa. STUDY DESIGN/MATERIALS AND METHODS The efficacy of antibacterial photodynamic inactivation, DNA fragmentation and protein carbonylation of three MDR P. aeruginosa strains and one susceptible strain was compared using TBO as the photosensitizer followed by red light irradiation (630 nm, 90 J/cm(2)) from a light-emitting diode light source. Subsequently, the efficacy of TBO photodynamic inactivation (TBO-PDI) on 60 MDR strains, including 11 with the efflux pump phenotype and 49 with no pump activity, was tested using the minimum lethal drug concentration (MLC) assay. RESULTS TBO-PDI caused similar bactericidal effect (6-7 logs of killing effect), DNA fragmentation and protein carbonylation in three MDR and one susceptible P. aeruginosa strains. Although the TBO accumulation assay indicated that TBO is a substrate for the efflux pump, TBO-PDI produce similar photobactericidal activity against 60 MDR P. aeruginosa strains, either with or without efflux-pump phenotype, and 19 susceptible strains. CONCLUSION MDR did not affect the susceptibility of P. aeruginosa strains to TBO-PDI. The efflux pump played an insignificant role in TBO-PDI of MDR P. aeruginosa.
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Affiliation(s)
- S P Tseng
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University College of Medicine, Taipei, Taiwan
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14
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Huang YH, Tseng SP, Hu JM, Tsai JC, Hsueh PR, Teng LJ. Clonal spread of SCCmec type IV methicillin-resistant Staphylococcus aureus between community and hospital. Clin Microbiol Infect 2007; 13:717-24. [PMID: 17403129 DOI: 10.1111/j.1469-0691.2007.01718.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [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: 11/27/2022]
Abstract
The staphylococcal chromosome cassette (SCC)mec types of 382 hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) isolates in Taiwan were analysed over a 7-year period (1999-2005). There was an abrupt increase in SCCmec type IV in HA-MRSA during 2005. The molecular epidemiology of a subset (n = 69) of HA-MRSA isolates with SCCmec types III, IV or V was characterised and compared with that of community-acquired MRSA (CA-MRSA) (n = 26, collected during 2005). Pulsed-field gel electrophoresis revealed three major pulsotypes (A, B and C) and 15 minor clones. Pulsotypes B and C, which contained isolates carrying SCCmec types IV and V, respectively, included both CA-MRSA and HA-MRSA isolates. Among 24 toxin genes analysed, five genes had significant differential distribution between CA-MRSA and SCCmec type III HA-MRSA. Furthermore, among SCCmec type IV isolates, the seb gene was detected more commonly in HA-MRSA. Analysis of representative members of the three major pulsotypes by multilocus sequence typing revealed two sequence types (STs), namely ST239 (SCCmecIII) and ST59 (SCCmecIV or SCCmecV). This suggests that ST59:SCCmecIV, which is usually community-acquired, has become an important nosocomial pathogen in the hospital studied.
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Affiliation(s)
- Y H Huang
- Department of Clinical Laboratory Sciences and Medical Biotechnology, National Taiwan University College of Medicine, Taipei, Taiwan
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15
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Oliveira C, Tsai JC, Liebmann JM, Ritch R. Angle-closure caused by an anterior segment membrane. Eye (Lond) 2006; 21:668-70. [PMID: 17128199 DOI: 10.1038/sj.eye.6702663] [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: 11/09/2022] Open
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16
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Kuo MC, Chang JM, Tsai JC, Chen HC, Tsai WC, Lai YH, Hwang SJ. Decreased B cells and IgA-secreting B cells partially explain the high prevalence of IgA deficiency in dialysis patients. Clin Nephrol 2006; 66:240-6. [PMID: 17063990 DOI: 10.5414/cnp66240] [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] [Indexed: 11/18/2022] Open
Abstract
AIMS We previously reported 2 hemodialysis (HD) patients with recurrent infections and selective immunoglobulin A deficiency (IgAD). We further demonstrated that serum IgA levels were lower and the prevalence of IgAD was higher in uremic patients. The exact mechanisms of IgAD in uremic patients largely remained unclear. In some patients, it was caused by anti-IgA antibody neutralization and subsequent destruction. We performed the present study to survey if there is any defect in IgA production. MATERIALS AND METHODS 288 patients were initially included for examination of serum immunoglobulins. 16 normal persons, 16 dialysis patients without IgAD, and 12 dialysis patients with IgAD were enrolled after the initial examination. Blood was drawn into heparinized tubes. WBC counts and lymphocyte percentage were examined by a CBC counter. Lymphocytes were separated by the Ficoll-Paque method. Flow cytometry was utilized to isolate the B cell and IgA-secreting B cell after staining with CD 19 phycoerythrin and FITC-conjugated rabbit anti-human IgA antibody. RESULTS There is no significant difference between WBC counts or total lymphocyte counts of these 3 groups. However, we found a lower percentage of total lymphocyte counts in dialysis patients, either with or without IgAD. The total B cell numbers were lower in dialysis patients with IgAD. In addition, there were fewer IgA-secreting B cells in dialysis patients with IgAD. CONCLUSION Decreased B cell and IgA-secreting B cell counts are seen in uremic patients with IgAD. This, in turn, indicates that there might be a defect of IgA production in some patients, rather than IgA destruction by anti-IgA antibodies as seen in some other patients. Further study is needed to investigate the mechanisms of decreased B cells and IgA-secreting B cells.
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Affiliation(s)
- M C Kuo
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Taiwan
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17
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Chang JM, Lin SP, Kuo HT, Tsai JC, Tomino Y, Lai YH, Chen HC. 7-84 parathyroid hormone fragments are proportionally increased with the severity of uremic hyperparathyroidism. Clin Nephrol 2005; 63:351-5. [PMID: 15909594 DOI: 10.5414/cnp63351] [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: 11/18/2022] Open
Abstract
AIMS Recent progress in PTH assay has revealed that the intact PTH assay kit in current use does not differentiate between the truncated 7-84 PTH molecule and the 1-84 PTH molecule. In our series, we examined the effectiveness of a new PTH assay as a noninvasive method of evaluating severity of uremic hyperparathyroidism. METHODS AND MATERIALS Two hundred and seventy hemodialysis (HD) patients recruited from three HD centers were included and divided into subgroups according to the conventional iPTH assay results. Pre-dialysis blood samples were collected and subjected to two different PTH assays: "intact" PTH assay (iPTH) and "whole" PTH (wPTH) assay. Two biochemical markers of bone remodeling were also examined. RESULTS In all cases, PTH levels determined by the wPTH assay were in the average 32.3% lower than those determined by the iPTH assay. The difference of the results of the two PTH assay methods, which indicated the portion of 7-84 PTH fragments of the total PTH molecules measured with the iPTH assay, was gradually increased while the severity of uremic hyperparathyroidism increased. Biochemical markers of bone formation/resorption showed a similar change. CONCLUSION The portion of the 7-84 PTH fragments and markers of increased bone turnover increased in proportion to the severity of uremic hyperparathyroidism. This finding disproves the hypothetical role of 7-84 PTH fragments alone as the noninvasive marker of low-turnover bone disease in HD patients.
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Affiliation(s)
- J M Chang
- Department of Nephrology, Kaohsiung Medical University, Taiwan
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18
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Tsai JC, Chan P, Wang CH, Jeng C, Hsieh MH, Kao PF, Chen YJ, Liu JC. The effects of exercise training on walking function and perception of health status in elderly patients with peripheral arterial occlusive disease. J Intern Med 2002; 252:448-55. [PMID: 12528763 DOI: 10.1046/j.1365-2796.2002.01055.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.1] [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: 11/20/2022]
Abstract
OBJECTIVE To determine the effects of 12-week exercise programme on ambulatory function, free-living daily physical activity and health-related quality of life in disabled older patients with intermittent claudication. DESIGN Prospective, randomized controlled trial. SETTING University Medical Center and Veterans Affairs Medical Center, Taipei, Taiwan. SUBJECTS Thirty-two of 64 patients with Fontaine stage II peripheral arterial occlusive disease (PAOD) were randomized to exercise training and 32 to usual care control. Five patients from the exercise group and six patients from the control group dropped out, leaving 27 and 26 patients, respectively, completing the study in each group. INTERVENTIONS Twelve weeks of treadmill exercise training. MAIN OUTCOME MEASURES Treadmill walking time to onset of claudication pain and to maximal claudication pain, 6-min walk distance, self-reported ambulatory ability and perceived health-related quality of life (QOL). RESULTS Compliance of exercise programme was 83% of the possible sessions. Exercise training increased treadmill walking time to onset of claudication pain by 88% (P < 0.001), time to maximal pain by 70% (P < 0.001), and 6-min walk distance by 21% (P < 0.001). SUBJECTS Perception of health-related QOL improved from 12% to 178% in the exercise group. These improvements were significantly better than the changes in the control group (P < 0.05). CONCLUSIONS Significant improvements in claudication following 12-week exercise training in elderly PAOD patients were observed. Increase in treadmill walking time to maximal claudication pain in these patients translated into the improvement of perceived physical health, which enabled the patients to become more functionally independent.
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Affiliation(s)
- J C Tsai
- Institute of Nursing, Taipei Medical University, Tapei, Taiwan.
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19
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MESH Headings
- Animals
- Coronavirus Infections/physiopathology
- Coronavirus Infections/virology
- Encephalitis, Viral/physiopathology
- Encephalitis, Viral/virology
- Hepatitis, Viral, Animal/physiopathology
- Hepatitis, Viral, Animal/virology
- Membrane Glycoproteins/chemistry
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Inbred C57BL
- Murine hepatitis virus/genetics
- Murine hepatitis virus/metabolism
- Murine hepatitis virus/pathogenicity
- Receptors, Virus/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Recombination, Genetic
- Spike Glycoprotein, Coronavirus
- Viral Envelope Proteins/chemistry
- Viral Envelope Proteins/genetics
- Viral Envelope Proteins/metabolism
- Virulence
- Virus Replication
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Affiliation(s)
- J C Tsai
- Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6076, USA
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20
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Tsai JC, Losert W, Voth GA, Gollub JP. Two-dimensional granular Poiseuille flow on an incline: multiple dynamical regimes. Phys Rev E Stat Nonlin Soft Matter Phys 2002; 65:011306. [PMID: 11800692 DOI: 10.1103/physreve.65.011306] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2001] [Indexed: 05/23/2023]
Abstract
We investigate experimentally the flow of a monolayer of spherical beads through a channel on a smooth incline that is bounded by rough sidewalls. Using high-speed video imaging and particle tracking, we measure the positions and velocities of all particles in the field of view. We find that the flows are accelerating and dilute if the channel exit is open. On the other hand, if the exit is constricted, flows can reach a state in which the local time-averaged velocity is invariant along the stream. In the latter case, we find a continuous transition from an oscillatory two-phase flow (2PF) regime with wide density variations to a uniform dense flow regime, depending on the channel width and the mean flow speed. These two regimes exhibit distinct density variation, time regularity, and transverse profiles. The rough sidewalls are found to be necessary for the 2PF regime. In the dense regions of both flows, particles exhibit temporary arches, long-range correlated velocities, inhomogenuous propagation of disturbances, and hexagonal lattice structures. On the other hand, the dilute regions of the two-phase flow are nearly collisionless. Existing models can neither fully describe the dynamics of both the dense and the dilute regions nor explain the spontaneous switching between them.
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Affiliation(s)
- J C Tsai
- Department of Physics and Astronomy, Haverford College, Haverford, Pennsylvania 19041, USA
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21
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Abstract
The purpose of this study was to evaluate refractive and anterior chamber depth changes after short-term dorzolamide use in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OH). This study was prospective and non-comparative and included 34 patients. Baseline refraction and anterior chamber depth were compared to the refraction and anterior chamber depth 14 days after commencing dorzolamide to determine if refraction or anterior chamber depth had been affected. Before dorzolamide use, the mean refractive error was -0.88 +/- 3.53 D (+/-SD). The mean refractive error was -0.94 +/- 3.65 D (+/-SD) two hours post-dose after 14 days of dorzolamide use, which was not significantly different (P = 0.50). The mean pre-treatment anterior chamber depth was 3.088 +/- 0.385 mm (+/-SD), which did not differ significantly from the post-treatment anterior chamber depth mean of 3.092 +/- 0.389 mm (+/-SD) (P = 0.88). The results of the study show that refraction and anterior chamber depth are not significantly altered by short-term dorzolamide use in patients with POAG and OH with no history of previous dorzolamide use.
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Affiliation(s)
- J C Tsai
- Department of Ophthalmology, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China.
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22
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Tsai JC, Liu L, Zhang J, Spokes KC, Topper JN, Aird WC. Epidermal growth factor induces Egr-1 promoter activity in hepatocytes in vitro and in vivo. Am J Physiol Gastrointest Liver Physiol 2001; 281:G1271-8. [PMID: 11668036 DOI: 10.1152/ajpgi.2001.281.5.g1271] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Early growth response-1 (Egr-1) is a transcription factor that couples short-term changes in the extracellular milieu to long-term changes in gene expression. Under in vitro conditions, the Egr-1 gene has been shown to respond to many extracellular signals. In most cases, these findings have not been extended to the in vivo setting. The goal of the present study was to explore the role of epidermal growth factor (EGF) in mediating Egr-1 expression in hepatocytes under both in vitro and in vivo conditions. In HepG2 cells, Egr-1 protein and mRNA were upregulated in the presence of EGF. In stable transfections of HepG2 cells, a 1,200-bp Egr-1 promoter contained information for EGF response via a protein kinase C-independent, mitogen-activated protein kinase-dependent signaling pathway. A promoter region containing the two most proximal serum response elements was sufficient to transduce the EGF signal. In transgenic mice that carry the Egr-1 promoter coupled to the LacZ reporter gene, systemic delivery of EGF by intraperitoneal injection resulted in an induction of the endogenous Egr-1 gene and the Egr-1-lacZ transgene in hepatocytes. Together, these results suggest that the 1,200-bp promoter contains information for EGF response in hepatocytes both in vitro and in intact animals.
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Affiliation(s)
- J C Tsai
- Department of Molecular Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
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23
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Lee YJ, Tsai JC. Angiotensin-converting enzyme gene insertion/deletion, not bradykinin B2 receptor -58T/C gene polymorphism, associated with angiotensin-converting enzyme inhibitor-related cough in Chinese female patients with non-insulin-dependent diabetes mellitus. Metabolism 2001; 50:1346-50. [PMID: 11699055 DOI: 10.1053/meta.2001.27212] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [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: 11/11/2022]
Abstract
To investigate the genetic susceptibility associated with cough related to angiotensin-converting enzyme inhibitor (ACEI) therapy in patients with type 2 diabetes, 189 non-insulin-dependent diabetes mellitus (NIDDM) patients with proteinuria or hypertension treated with perindopril were studied. Cough was considered to be present if the patients had been bothered by a cough during treatment and if they had had related symptoms for at least 2 weeks without an identifiable cause. Polymerase chain reaction (PCR) coupled with single-strand conformation polymorphism (SSCP) was used to detect polymorphisms of ACE and bradykinin B2-receptor genes. After 8 weeks of treatment, 49.2% (93 of 189) of our NIDDM patients were found to be suffering from ACEI-related cough. ACEI-related cough was mainly associated with female patients, with 71.7% (76 of 106) of female and only 20.5% (17 of 83) of male patients experiencing cough after ACEI treatment. There was a significant association of ACE II genotype with ACEI-related cough. The genotype frequencies were 58.2% for II, 47.8% for ID, and 16.7% for DD in patients with ACEI-associated cough and 41.8% for II, 52.2% for ID, and 83.3% for DD in subjects without ACEI-associated cough (chi(2) = 10.268; df = 2, P =.006). As female patients made up the majority of the subjects suffering from ACEI-related cough, we further analyzed the association of ACE I/D genotype with ACEI-related cough separately by sex. Male patients with ACEI-related cough were not associated with ACE I/D genotype distribution, while female patients were strongly associated with ACE I/D genotype polymorphism (chi(2) = 16.12; df = 2; P <.001). There was no association between the bradykinin B2 receptor gene -58T/C polymorphism with ACEI-related cough. In conclusion, our results indicate that Chinese diabetic female subjects are susceptible to ACEI-related cough, and this susceptibility may be genetically predetermined.
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Affiliation(s)
- Y J Lee
- Department of Clinical Research, Ping-Tung Christian Hospital, Ping-Tung, Taiwan, Republic of China
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Abid MR, Tsai JC, Spokes KC, Deshpande SS, Irani K, Aird WC. Vascular endothelial growth factor induces manganese-superoxide dismutase expression in endothelial cells by a Rac1-regulated NADPH oxidase-dependent mechanism. FASEB J 2001; 15:2548-50. [PMID: 11641265 DOI: 10.1096/fj.01-0338fje] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.6] [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: 11/11/2022]
Abstract
Vascular endothelial growth factor (VEGF) is a potent vascular endothelial cell-specific mitogen that modulates endothelial cell function. In the present study, we show that VEGF induces manganese-superoxide dismutase (MnSOD) mRNA and protein in human coronary artery endothelial cells (HCAEC) and pulmonary artery endothelial cells. VEGF-mediated induction of MnSOD mRNA was inhibited by pretreatment with the NADPH oxidase inhibitors, diphenyleneiodonium (DPI), and 4-(2-aminoethyl)-benzenesulfonyl fluoride, but not with the nitric oxide synthase inhibitor L-NAME (N-monomethyl-L-arginine) or the xanthine oxidase inhibitor allopurinol. VEGF stimulation of MnSOD was also inhibited by adenoviral-mediated overexpression of catalase Cu, Zn-SOD and a dominant-negative form of the small GTPase component of NADPH oxidase Rac1 (Rac1N17). Treatment of HCAEC with VEGF resulted in a transient increase in ROS production at 20 min, as measured by 2,7-dichlorodihydrofluorescein oxidation. This effect was abrogated by expression of Rac1N17. Taken together, these findings suggest that VEGF induces MnSOD by an NADPH oxidase-dependent mechanism and that VEGF signaling in the endothelium is coupled to the redox state of the cell.
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MESH Headings
- Adenoviridae/genetics
- Blotting, Northern
- Blotting, Western
- Catalase/genetics
- Catalase/metabolism
- Cells, Cultured
- Dose-Response Relationship, Drug
- Endothelial Growth Factors/pharmacology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Free Radical Scavengers/pharmacology
- Gene Expression Regulation, Enzymologic/drug effects
- Genetic Vectors/genetics
- Humans
- Lymphokines/pharmacology
- NADPH Oxidases/antagonists & inhibitors
- NADPH Oxidases/metabolism
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Reactive Oxygen Species/metabolism
- Superoxide Dismutase/drug effects
- Superoxide Dismutase/genetics
- Superoxide Dismutase/metabolism
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
- rac1 GTP-Binding Protein/genetics
- rac1 GTP-Binding Protein/physiology
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Affiliation(s)
- M R Abid
- Departments of Medicine and Molecular Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 01125, USA
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Sivak-Callcott JA, O'Day DM, Gass JD, Tsai JC. Evidence-based recommendations for the diagnosis and treatment of neovascular glaucoma. Ophthalmology 2001; 108:1767-76; quiz1777, 1800. [PMID: 11581047 DOI: 10.1016/s0161-6420(01)00775-8] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.2] [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: 11/23/2022] Open
Abstract
PURPOSE To succinctly update information on the pathogenesis, etiology, diagnosis, and treatment of neovascular glaucoma based on a systematic review of available literature and to provide summary recommendations rated for their importance to clinical outcome. CLINICAL RELEVANCE Neovascular glaucoma is a devastating ocular disease that often results in loss of vision. The current standard of care includes retinal ablation and control of increased intraocular pressure with medical and surgical therapy. LITERATURE REVIEW METHODOLOGY: The authors conducted a MEDLINE literature search of articles published in English from 1966 to the present. Each article reviewed was rated as to the strength of evidence it provided, and summary ratings for the strength of evidence supporting clinical recommendations were generated. RESULTS Level A (most important to patient outcome) recommendations for the diagnosis of neovascular glaucoma include a high index of suspicion, a full ocular examination including undilated gonioscopy, and pupil examination. In regard to treatment, Level A recommendations include treatment of the underlying disease origin, complete panretinal photocoagulation (if retinal ischemia is a factor), and medical control of both elevated intraocular pressure and inflammation. Level B recommendations (moderately important to patient outcome) encompass glaucoma surgery to control intraocular pressure when medical therapy is unsuccessful, although the ideal surgical procedure is unknown. Currently, trabeculectomy with antimetabolite therapy, aqueous shunt implants, and diode laser cyclophotocoagulation are the preferred surgical treatment options. CONCLUSIONS The current literature on neovascular glaucoma has few articles that provide strong evidence in support of therapy recommendations (level I). Future research studies are needed to address areas in which the current evidence is moderately strong (level II) or weak, consisting only of a consensus of expert opinion (level III). Whenever practicable, these studies should be prospective, randomized clinical trials.
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Affiliation(s)
- J A Sivak-Callcott
- Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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Abstract
PURPOSE To report the histopathologic and immunohistochemical findings from the iridectomy specimen of a patient with acquired unilateral iris heterochromia due to latanoprost. PATIENT AND METHODS A 45-year-old woman with open-angle glaucoma and unilateral iris heterochromia was evaluated for uncontrolled intraocular pressure increase. Subsequently, the patient underwent trabeculectomy with mitomycin C and an iridectomy specimen was obtained for analysis. RESULTS The histopathologic analysis of the iridectomy specimen did not reveal any nuclear atypia, nuclear crowding, or mitotic figures. Immunohistochemical studies showed that the iris melanocytes were negative for HMB45 and S-100, and weakly positive for Melan A. CONCLUSION Latanoprost-associated iris color change may exhibit a diffuse, uniform, dark velvet-brown appearance, thereby simulating diffuse iris melanoma. Histopathologic and immunohistochemical analysis confirmed the benign characteristics of the affected iris melanocytes.
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Affiliation(s)
- J C Tsai
- Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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27
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Tsai JC, Sheu HM, Hung PL, Cheng CL. Effect of barrier disruption by acetone treatment on the permeability of compounds with various lipophilicities: implications for the permeability of compromised skin. J Pharm Sci 2001; 90:1242-54. [PMID: 11745777 DOI: 10.1002/jps.1077] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [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: 11/07/2022]
Abstract
The permeability of compromised skin barrier was investigated in vitro using acetone-disrupted hairless mouse skin as a model membrane. The effect of compound lipophilicity was studied using sucrose, caffeine, hydrocortisone, estradiol, and progesterone as model compounds. The results demonstrated that permeability barrier disruption by acetone treatment significantly enhanced the permeability of the skin to both hydrophilic and amphipathic compounds, including sucrose, caffeine and hydrocortisone. This effect was more prominent with caffeine and hydrocortisone at different transepidermal water loss (TEWL) levels. Acetone treatment, however, didn't appear to alter the percutaneous penetration of highly lipophilic compounds, such as estradiol and progesterone. The characteristics of skin permeability were described by parabolic relationships between log P(WS) (permeability coefficient of whole skin) and log K(O/W) (octanol/water partition coefficient) at different degrees of permeability barrier disruption. The optimal log K(O/W) of compounds for skin penetration appeared to decrease with an increase in TEWL levels. The maximal permeability achieved was similar through skin displaying different TEWL levels. In an attempt to explore the underlying mechanisms for the changes in skin permeability, the stratum corneum/normal saline partition coefficients of water, caffeine, and hydrocortisone either decreased or remained unaffected with an increase in TEWL. Electron microscopic examinations have revealed reductions in stratum corneum lipid content and alterations in intercellular membrane structures as a result of acetone treatment, whereas negligible changes in the number of horny layers were observed by safranin staining of the stratum corneum. We have concluded that the enhancement in skin permeability to both hydrophilic and amphipathic compounds by acetone treatment arose mainly because of the increase in stratum corneum diffusivity at higher TEWL levels. The results imply the possibility of using both TEWL and drug lipophilicity to predict alterations in skin permeability and hence the dose adjustment of topically applied medication for patients with impaired skin barrier function.
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Affiliation(s)
- J C Tsai
- Institute of Clinical Pharmacy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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28
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Abstract
Rice hull ash (RHA) of large surface area was obtained by acid wash and then calcination at 600 degrees C for 4 h. The white ash was then mixed with kaolin and starch to make pellet adsorbents with reasonable strength to be utilized in a packed column. Both ash and pellet samples showed good adsorption capacities toward the organic substances in wastewater. Furthermore, the surface nature of the white ash and pellet adsorbent could be modified through either hydration or esterification reactions. Corresponding changes in silanol concentrations were successfully correlated to changes in adsorption capacity toward either Congo red or vacuum pump oil molecules.
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Affiliation(s)
- K S Chou
- Department of Chemical Engineering, National Tsing Hua University, Taiwan, ROC.
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29
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Abstract
Previous studies have demonstrated that permeability barrier disruption by acetone treatment significantly enhances skin permeability to both hydrophilic and amphipathic compounds, but not to highly lipophilic compounds. The purpose of the present study was to investigate the dependence of permeability on molecular weight (MW) in acetone-disrupted hairless mouse skin in contrast to normal skin. Penetration of polyethylene glycol (PEG) 300, 600, and 1,000 over 12 h was measured using diffusion cells. High-performance liquid chromatographic methods with refractive index detection were used to separate and quantitate the individual oligomeric species in the PEG samples. Percutaneous penetration of PEGs exhibited slightly steeper MW dependency at a transepidermal water loss (TEWL) of 30-41 g/m2 per h in comparison with TEWLs of 0-10 (control skin), 10-20, and 20-30 g/m2 per h, with a higher percentage of smaller oligomer PEGs penetrating than larger ones. Increasing the TEWL of the skin increased the penetration of all the PEG oligomers, and the degree of the enhancement relative to penetration through control skin increased with MW and was maximal for oligomers with a MW ranging from 326 to 414 Da. Within the limit of quantitation of the assay, the MW cut-off for PEG penetration across mouse skin with TEWLs of 0-10, 10-20, and 20-30 g/m2 per h was 414, 590, and 942 Da, respectively, while all the measurable oligomers up to MW 1,074 Da were able to penetrate skin with TEWLs in the range 30-41 g/m2 per h. The results suggest that not only higher amounts but also more varieties of chemicals may penetrate skin with a compromised barrier than normal skin, implying a higher risk of intoxication and hypersensitization by environmental agents through diseased skin with impaired barrier function.
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Affiliation(s)
- J C Tsai
- Institute of Clinical Pharmacy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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30
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Chen WC, Huang JK, Cheng JS, Tsai JC, Chiang AJ, Chou KJ, Liu CP, Jan CR. AM-404 elevates renal intracellular Ca(2+), questioning its selectivity as a pharmacological tool for investigating the anandamide transporter. J Pharmacol Toxicol Methods 2001; 45:195-8. [PMID: 11755382 DOI: 10.1016/s1056-8719(01)00148-4] [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: 11/21/2022]
Abstract
The effect of N-(4-hydroxyphenyl)-arachidonamide (AM-404), a drug commonly used to inhibit the anandamide transporter, on intracellular free Ca(2+) levels ([Ca(2+)](i)) was studied in Madin Darby canine kidney (MDCK) cells. [Ca(2+)](i) was measured using fura-2 as a Ca(2+) indicator. Between 2 and 40 microM, AM-404 increased [Ca(2+)](i) in a concentration-dependent fashion with an EC(50) value of 20 microM. Removal of extracellular Ca(2+) abolished the [Ca(2+)](i) signals. The [Ca(2+)](i) increase was nearly abrogated by 10 microM La(3+), but was insensitive to 50 microM Ni(2+) and 10 microM of nifedipine, nimodipine, nicardipine, and verapamil. At a concentration that did not increase [Ca(2+)](i), AM-404 (1 microM) did not alter the [Ca(2+)](i) increases induced by 10 microM ATP and 1 microM bradykinin. AM-404 (5 microM) also increased [Ca(2+)](i) in Chang liver cells, PC3 human prostate cancer cells, BFTC human bladder cancer cells, and MG63 human osteoblast-like cells. Together, this study shows for the first time that AM-404 at concentrations commonly used to inhibit the anandamide transporter in various systems induced an increase in [Ca(2+)](i) in different cell types. The [Ca(2+)](i) increase was solely due to extracellular Ca(2+) influx. Thus caution must be exercised in using AM-404 as a selective inhibitor of the anandamide transporter.
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Affiliation(s)
- W C Chen
- Department of Surgery, Ping Tung Christian Hospital, Taipei 900, Taiwan
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31
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Abstract
The cause of multiple sclerosis (MS) is unknown. Despite indications from epidemiological and identical-twin studies that MS is infectious, no virus or other infectious agent has been tightly linked to disease. The isolation of Chlamydia pneumoniae from the cerebrospinal fluid (CSF) of MS patients and the detection of both Chlamydia-specific DNA and antibody in MS CSF have been reported. Other analyses of brain and CSF have shown no significant difference in C. pneumoniae-specific DNA or antibody between MS and control subjects. Recent work has revealed intrathecal production of C. pneumoniae-specific IgG in only 24% of MS patients compared with 5% of control patients. More importantly, the major CSF oligoclonal bands from MS patients did not react to C. pneumoniae.
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Affiliation(s)
- J C Tsai
- Dept of Microbiology and the Neuroscience Graduate Group, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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32
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Abstract
The kidney is an important site of endothelin-1 (ET-1) production and is particularly susceptible to ET-1 action. Infusion of ET-1 in rats induces both functional and morphological alterations in the kidneys. Increased plasma level of ET-1 has been reported in patients with chronic renal failure. However, there are still no reports on the plasma and urinary ET-1 levels in patients with focal segmental glomerulosclerosis (FSGS). In the present study, we have measured the plasma concentration and urinary excretion rate of ET-1 in 15 patients with nephrotic syndrome due to FSGS, and observed the serial changes of plasma and urinary ET-1 in nephrotic rats with FSGS, induced by repeated injection with puromycin aminonucleoside (PAN). ET-1 was measured with radioimmunoassay. The results showed that plasma ET-1 concentration in FSGS patients was significantly higher than in normal controls (P < 0.05), and that urinary ET-1 excretion rate was also significantly higher in FSGS patients than in normal controls (P < 0.01). In FSGS patients, the plasma and urinary ET-1 was significantly correlated (P < 0.05), and the urinary ET-1 excretion rate was significantly correlated with the amount of proteinuria (P < 0.05) and the glomerular sclerosing score (P < 0.01). In the ten rats with PAN-induced FSGS, serial examination showed a significant increase in plasma ET-1 after 8 weeks of injections, while the urinary ET-1 excretion rate showed a biphasic increase that showed a peak after 4 to 6 weeks. The same changes in plasma and urinary ET-1 levels were not observed in control rats injected with normal saline at the same frequency. Our results suggest that ET-1 may be involved in the pathogenesis of FSGS in both humans and rats.
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Affiliation(s)
- H C Chen
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
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33
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Kuo MC, Chang JM, Hwang SJ, Tsai JC, Lai YH. High prevalence of selective immunoglobulin A deficiency in peritoneal dialysis patients. Adv Perit Dial 2001; 16:237-42. [PMID: 11045302] [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: 02/18/2023]
Abstract
We encountered two hemodialysis (HD) patients with recurrent infections and complete immunoglobulin A deficiency (IgAD). To survey the possibility of a similar occurrence in other populations, we conducted the present study. We used nephelometry to examine the levels of immunoglobulins G (IgG), A (IgA), and M (IgM) in 42 continuous ambulatory peritoneal dialysis (CAPD) patients, 246 HD patients, 56 chronic renal failure (CRF) patients, and 250 normal adults. Four CAPD patients (9.5%) and five HD patients (2.0%) were found to be completely IgA deficient (IgA < 6.67 mg/dL). Peritoneal dialysis patients therefore had a significantly higher prevalence of IgAD compared with HD and CRF patients. The underlying diseases leading to dialysis therapy in the IgAD patients varied. Their dialysis durations also varied. The occurrence rate of peritonitis in CAPD patients with IgAD was no higher than in patients without IgAD. The clinical significance of IgAD was focused on mucosal immunity, but the exact prevalence of infection was difficult to define. However, these patients' medical records did suggest more frequent respiratory tract infections and cellulitis events than did the records of patients without IgAD. Two PD patients with IgAD died of pneumonia. Immunodiffusion and indirect ELISA methods were used to detect the presence of auto-antibodies, successfully identifying them in three patients. Further research is needed to study other mechanisms of IgAD.
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Affiliation(s)
- M C Kuo
- Department of Medicine, Kaohsiung Medical University, Taiwan
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Abstract
PURPOSE To report a case of recurrent epithelial inclusion cyst of the iris treated with needle aspiration and endodiathermy. METHODS Case report. A 27-year-old man with a history of congenital cataracts, congenital nystagmus, cataract surgery in each eye at 3 years of age, and a long-standing iris epithelial cyst presented with decreased vision of 20/400 in the better seeing left eye. The reduced vision was diagnosed secondary to growth of the iris inclusion cyst over the pupil. RESULTS The iris cyst, which occluded the chamber angle and pupil, was treated with aspiration, separation of the cyst wall from the cornea, and endodiathermy. Twelve months after cyst surgery, no evidence existed of epithelial cyst regrowth. The visual function was significantly improved, although Snellen visual acuity was unchanged at 20/400. CONCLUSION The minimal invasiveness of needle aspiration and diathermy can result in a satisfactory outcome without undertaking more extensive and invasive surgical treatments for epithelial inclusion cysts of the anterior chamber.
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Affiliation(s)
- J C Tsai
- Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, 8000 Medical Center East, Nashville, TN 37232, USA.
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Singh K, Mehta K, Shaikh NM, Tsai JC, Moster MR, Budenz DL, Greenfield DS, Chen PP, Cohen JS, Baerveldt GS, Shaikh S. Trabeculectomy with intraoperative mitomycin C versus 5-fluorouracil. Prospective randomized clinical trial. Ophthalmology 2000; 107:2305-9. [PMID: 11097613 DOI: 10.1016/s0161-6420(00)00391-2] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.2] [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: 11/16/2022] Open
Abstract
OBJECTIVE To evaluate the relative efficacy and safety of 5-fluorouracil (5-FU) and mitomycin C (MMC) when used as adjuncts with primary trabeculectomy in eyes not at high risk for failure. DESIGN Prospective multicenter, randomized clinical trial. PARTICIPANTS One hundred thirteen patients with primary open-angle, pseudoexfoliative, pigmentary, or angle-closure glaucoma undergoing primary trabeculectomy were recruited. METHODS One eye of each patient was randomized to receive either 5-FU (50 mg/ml for 5 minutes) or MMC (0.4 mg/ml for 2 minutes). MAIN OUTCOME MEASURES Intraocular pressure (IOP), visual acuity, complications, and interventions were documented at fixed intervals after surgery. The study also examined progression of visual field loss, long-term complications, and bleb appearance 3 years after surgery. RESULTS Of the 108 patients with complete perioperative information, 54 eyes received 5-FU and 54 received MMC. The proportion of patients reaching different predefined target IOPs after surgery was slightly higher in the MMC group than in the 5-FU group. This difference was less than 25%, which would have been necessary to achieve statistical significance with a power of 0.8 and the sample size used. Likewise, there was no statistically significant difference between the groups with regard to mean preoperative IOP, complications, or interventions. Mean postoperative follow-up was 309 and 330 days in the 5-FU and MMC groups, respectively (P = 0.593). CONCLUSIONS 5-Fluorouracil and MMC were found to be equally safe and effective adjuncts to primary trabeculectomy in the short- and medium-term postoperative periods.
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Affiliation(s)
- K Singh
- Stanford University School of Medicine, Stanford, California, USA.
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36
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Abstract
The early growth response (Egr)-1 transcription factor serves to couple changes in the extracellular environment to alterations in gene expression. An understanding of the mechanisms that underlie Egr-1 gene regulation should provide important insights into how environmental signals are transduced by endothelial cells. The aim of the present study was to determine whether epidermal growth factor (EGF) induces Egr-1 expression in endothelial cells. In ECV304 cells, Egr-1 mRNA and protein levels were increased in response to EGF. In stable transfection assays, the 1,200-bp promoter of the mouse Egr-1 gene contained information for EGF response via a protein kinase C-independent, mitogen-activated protein kinase-dependent pathway. The endogenous Egr-1 gene was similarly responsive to EGF in primary human umbilical vein endothelial cells, human coronary artery endothelial cells, and rat fat pad endothelial cells, but not in bovine aortic endothelial cells, calf pulmonary artery endothelial cells, or PY-4-1 endothelial cells. Together, these results suggest that the Egr-1 gene is responsive to EGF in a subset of endothelial cells.
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Affiliation(s)
- J C Tsai
- Department of Molecular Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
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37
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Tsai JC, Liu L, Cooley BC, DiChiara MR, Topper JN, Aird WC. The Egr-1 promoter contains information for constitutive and inducible expression in transgenic mice. FASEB J 2000; 14:1870-2. [PMID: 11023970 DOI: 10.1096/fj.99-1072fje] [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: 11/11/2022]
Abstract
Egr-1 is an immediate early gene that couples short-term changes in the extracellular milieu to long-term changes in gene expression. Under in vitro conditions, the Egr-1 gene is expressed in many cell types and is induced by a wide variety of extracellular signals. The mechanisms by which the Egr-1 gene is regulated in vivo remain poorly understood. In this study, we have generated transgenic mice with a construct containing 1200 bp of the mouse Egr-1 promoter coupled to nuclear localized LacZ. In multiple independent lines of mice, reporter gene expression was detected in subsets of endothelial cells, vascular smooth-muscle cells, cardiomyocytes, neurons, and hepatocytes. This pattern closely resembled that of the endogenous gene. After partial hepatectomy, reporter gene activity was upregulated between two- and fivefold in regenerating livers. Taken together, these findings suggest that the Egr-1 promoter contains information for appropriate spatial and temporal expression in vivo.
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Affiliation(s)
- J C Tsai
- Department of Molecular Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA
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38
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Abstract
Demyelination is the pathologic hallmark of the human immune-mediated neurologic disease multiple sclerosis, which may be triggered or exacerbated by viral infections. Several experimental animal models have been developed to study the mechanism of virus-induced demyelination, including coronavirus mouse hepatitis virus (MHV) infection in mice. The envelope spike (S) glycoprotein of MHV contains determinants of properties essential for virus-host interactions. However, the molecular determinants of MHV-induced demyelination are still unknown. To investigate the mechanism of MHV-induced demyelination, we examined whether the S gene of MHV contains determinants of demyelination and whether demyelination is linked to viral persistence. Using targeted RNA recombination, we replaced the S gene of a demyelinating virus (MHV-A59) with the S gene of a closely related, nondemyelinating virus (MHV-2). Recombinant viruses containing an S gene derived from MHV-2 in an MHV-A59 background (Penn98-1 and Penn98-2) exhibited a persistence-positive, demyelination-negative phenotype. Thus, determinants of demyelination map to the S gene of MHV. Furthermore, viral persistence is insufficient to induce demyelination, although it may be a prerequisite for the development of demyelination.
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Affiliation(s)
- J Das Sarma
- Division of Neuropathology, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia 19104, USA
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39
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Affiliation(s)
- S Lin
- Center for Optoelectronic Biomedicine, National Taiwan University College of Medicine, Taipei, Taiwan.
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40
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Liu L, Tsai JC, Aird WC. Egr-1 gene is induced by the systemic administration of the vascular endothelial growth factor and the epidermal growth factor. Blood 2000; 96:1772-81. [PMID: 10961876] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Egr-1 is a transcription factor that couples short-term changes in the extracellular milieu to long-term changes in gene expression. In cultured endothelial cells, the Egr-1 gene has been shown to respond to a variety of extracellular signals. However, the physiological relevance of these findings remains unclear. To address this question, the growth factor-mediated response of the Egr-1 gene under in vivo conditions was analyzed. To that end, either vascular endothelial growth factor (VEGF) or epidermal growth factor (EGF) was injected into the intraperitoneal cavity of mice. Growth factors were delivered to all tissues examined, as evidenced by the widespread distribution of I(125)-labeled growth factors and the phosphorylation of their respective receptors. In Western blot analyses of whole-tissue extracts, Egr-1 protein levels were shown to be induced in the heart, brain, liver, and spleen of VEGF-treated mice, and in the heart, lung, brain, liver and skeletal muscle of EGF-treated animals. Changes in Egr-1 levels did not correlate with changes in receptor phosphorylation or ERK1/2 phosphorylation. In Northern blot analyses, VEGF induced Egr-1 mRNA levels in all tissues examined except lung and kidney, whereas EGF led to increased transcripts in all tissues except kidney. In immunofluorescence studies, VEGF induced Egr-1 in microvascular endothelial cells of the heart and liver, and EGF induced Egr-1 in the microvascular bed of skeletal muscle. Taken together, these results suggest that the Egr-1 gene is differentially regulated in response to systemically administered VEGF and EGF. (Blood. 2000;96:1772-1781)
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MESH Headings
- Animals
- Brain/drug effects
- Brain/metabolism
- DNA-Binding Proteins/drug effects
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Early Growth Response Protein 1
- Endothelial Growth Factors/pharmacology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Epidermal Growth Factor/pharmacology
- ErbB Receptors/metabolism
- Female
- Heart/drug effects
- Immediate-Early Proteins
- Injections, Intraperitoneal
- Liver/drug effects
- Liver/metabolism
- Lung/drug effects
- Lung/metabolism
- Lymphokines/pharmacology
- Mice
- Microscopy, Confocal
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Myocardium/metabolism
- Phosphorylation/drug effects
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor Protein-Tyrosine Kinases/metabolism
- Receptors, Growth Factor/metabolism
- Receptors, Vascular Endothelial Growth Factor
- Spleen/drug effects
- Spleen/metabolism
- Transcription Factors/drug effects
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
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Affiliation(s)
- L Liu
- Department of Molecular Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
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41
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Abstract
BACKGROUND AND OBJECTIVE The purpose of this study was to compare the differential susceptibility to photodynamic therapy (PDT) mediated damage in human U-105MG glioma cells and CH-157MN meningioma cells in vitro using 5-amino-levulinic acid (ALA) as photosensitizer, and to determine if growth factors would enhance PDT-mediated damage of these cells. STUDY DESIGN/MATERIALS AND METHODS U-105MG or CH-157MN cells were irradiated with polychromatic light in the presence of ALA. A Xenon lamp (150 W) was used as the light source. For the study on the effect of growth factor on ALA-PDT, cells were cultured in serum free medium for 24 hours. Epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), or platelet derived growth factor BB (PDGF-BB) was added to achieve a final concentration of 50 ng/ml. 30 minutes later, cells were incubated with ALA (100 microg/ml) for 24 hours, washed, and irradiated with light (11 J/cm2). MTT tetrazolium assays were performed 24 hours after light irradiation. RESULTS The inhibition of metabolic cellular function in U-105MG cells by ALA depended on both light energy density and ALA concentration. The susceptibility to ALA-PDT was profoundly lower for CH-157MN meningioma cells than U-105MG glioma cells. When incubated with ALA (100 microg/ml), U-105MG cells exhibited an LD50 around 8 J/cm2 of light irradiation, whereas that of CH-157MN cells was more than 25 J/cm2. EGF, bFGF, or PDGF-BB did not have any effects on the susceptibility of these two cell lines to ALA-PDT. CONCLUSION ALA-PDT was more effective in killing U-105MG glioma cells than CH-157MN meningioma cells. The differential susceptibility was likely due to differential accumulation of PpIX in these cells. EGF, bFGF, or PDGF-BB did not have stimulatory or inhibitory effect on the efficiency of ALA-PDT.
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Affiliation(s)
- J C Tsai
- Laser Medicine Research Center, College of Medicine, National Taiwan University, Taipei.
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42
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Tsai JC, Lim KB, Lin SY, Kao MC. Thermographic study of palmar and facial skin temperature of hyperhidrosis patients before and after thoracic sympathectomy. J Formos Med Assoc 2000; 99:466-71. [PMID: 10925552] [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: 02/17/2023] Open
Abstract
PURPOSE The purpose of this study was to investigate the roles of the second thoracic sympathetic segment in the sympathetic innervation of the hands and face, and to compare skin temperature changes in the palms, fingers, face, and neck of palmar hyperhidrosis (PH) patients before and after endoscopic thoracic sympathectomy. METHODS Twenty-two patients, 14 women and eight men, with severe PH were treated with endoscopic ablation of the T2 segment. The skin temperatures of the hands, neck, and face were assessed by infrared thermography both before and after operation. RESULTS All obtained satisfactory relief of PH. Before sympathectomy, thermography revealed that the palmar skin temperature (PST) was significantly lower than the facial temperature by 1.3 degrees C (paired t-test, p < 0.005). After sympathectomy, thermography showed significant elevations in temperature mainly of the thenars, palms, digits, and nose, but not of the forehead, mandible, or neck (ANOVA, p < 0.05 with Bonferroni t-test). The variations in PST among PH patients were much greater preoperatively than postoperatively. More prominent postoperative PST elevation was found in PH patients with lower preoperative PST (r = 0.898, p < 0.001). CONCLUSIONS These findings demonstrate that the T2 segment is the key source of sympathetic innervation to the hand and that the T2 segment contributes only trivial sympathetic innervation to the face. The results of the present thermography studies offer descriptive information about the autonomic innervation of the upper thoracic sympathetic trunk.
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Affiliation(s)
- J C Tsai
- Laser Medicine Research Center, College of Medicine, National Taiwan University, Taipei, Taiwan
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43
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Abstract
We have previously reported an in vitro inhibitory effect of endothelin-1 (ET-1) on parathyroid hormone (PTH) secretion. In the present experiment, ET-1 was infused into rabbits to study the in vivo effect of ET-1 on the changes in calcium, magnesium, PTH and calcitonin concentrations. Femoral arteries and veins of anesthetized male rabbits were cannulated to monitor vital signs, blood sampling and infusion of the agents being studied. Infusion of ET-1 (1, 5, 10 and 20 ng/kg per min) induced a dose-dependent decline in plasma ionized calcium concentrations from 6.68+/-0.26 to 5.50+/-0.46 mg/dl (P<0.05) and a decrease in calcitonin concentrations from 48.6+/-6.5 to 32.5+/-4.7 pg/ml. PTH concentrations increased from 58.3+/-10.2 to 159.4+/-22.1 pg/ml. In a separate experiment, calcium gluconate solution was simultaneously infused to keep calcium concentrations steady, thereby proving a calcium 'clamp'. In normal calcium concentration, ET-1 infusion gradually decreased PTH concentrations from 71.4+/-8.6 to 38.0+/-6.2 pg/ml. We further infused sodium citrate solution to decrease the calcium concentration (2.0 mg/dl less) and calcium gluconate solution was infused to keep calcium concentrations steadily less than normal. PTH concentrations were initially stimulated by the induction of hypocalcemia (68.1+/-11.2 to 135.6+/-8.5 pg/ml), but decreased by ET-1 infusion (135.6+/-8.5 to 85.1+/-15.2 pg/ml). Plasma magnesium concentrations did not change significantly throughout the entire study and calcitonin concentrations were not significantly changed during the calcium clamp studies. Serum phosphate and 1,25-(OH)(2) vitamin D(3) concentrations were also measured, but they also did not change significantly. In conclusion, ET-1 exhibited an in vivo acute hypocalcemic action, independent of calcitonin. It also directly decreased PTH secretion if serum calcium concentrations were kept steady. The above findings are consistent with the results of our previous in vitro experiment.
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Affiliation(s)
- J M Chang
- Division of Nephrology, Department of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
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44
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Abstract
Bacteroides thetaiotaomicron is the second most frequently encountered species of the anaerobes isolated from clinical specimens. We developed a PCR-based assay for the rapid identification of B. thetaiotaomicron. Specific primers were based on shared amplicons of about 1.2 kb generated from B. thetaiotaomicron by randomly amplified polymorphic DNA. This 1.2-kb fragment was sequenced and then used to design a set of PCR amplification primers. This PCR generated an amplification product of 721 bp, which was unique to all 65 isolates of B. thetaiotaomicron tested. There was no amplification with isolates of other bacterial species. Restriction enzyme digestion of the amplification product and dot blot hybridization further verified the specificity of the assay. These results suggest that this PCR assay targets a nucleotide sequence that is strongly conserved in B. thetaiotaomicron. This simple and rapid PCR assay provides a rapid and accurate method for identification of B. thetaiotaomicron and shows promise for the detection of B. thetaiotaomicron in clinical samples.
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Affiliation(s)
- L J Teng
- School of Medical Technology, National Taiwan University College of Medicine, Taipei, Taiwan.
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45
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Lee YJ, Chiang YF, Tsai JC. Severe nonproductive cough and cough-induced stress urinary incontinence in diabetic postmenopausal women treated with ACE inhibitor. Diabetes Care 2000; 23:427-8. [PMID: 10868884 DOI: 10.2337/diacare.23.3.427] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Chang JM, Hwang SJ, Kuo HT, Tsai JC, Guh JY, Chen HC, Tsai JH, Lai YH. Fatal outcome after ingestion of star fruit (Averrhoa carambola) in uremic patients. Am J Kidney Dis 2000; 35:189-93. [PMID: 10676715 DOI: 10.1016/s0272-6386(00)70325-8] [Citation(s) in RCA: 61] [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] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Clinical outcome of dialysis patients after eating star fruit (Averrhoa carambola) varies, but it may be fatal. In the past 10 years, 20 such patients were treated in our hospital when they developed clinical symptoms after eating the fruit or drinking star fruit juice. Their initial presentations included sudden-onset limb numbness, muscle weakness, intractable hiccups, consciousness disturbance of various degrees, and seizure. No other major events that might be responsible for these symptoms could be identified. Eight patients died, including one patient with a serum creatinine level of 6.4 mg/dL who had not yet begun dialysis. The clinical manifestations of the survivors were similar to those who died except for consciousness disturbance and seizure. Death occurred within 5 days despite emergent hemodialysis and intensive medical care. The survivors' symptoms usually became less severe after supportive treatment, and these patients subsequently recovered without obvious sequelae. The purpose of this article is to report that patients with renal failure who ingest star fruit may develop neurological symptoms and also run the risk for death in severe cases. Mortality may also occur in patients with chronic renal failure not yet undergoing dialysis.
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Affiliation(s)
- J M Chang
- Department of Medicine, Kaohsiung Medical University, Taiwan
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Tsai JC, Hsieh CH, Hsu TC. A new dynamic finite-state vector quantization algorithm for image compression. IEEE Trans Image Process 2000; 9:1825-1836. [PMID: 18262920 DOI: 10.1109/83.877206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The picture quality of conventional memory vector quantization techniques is limited by their supercodebooks. This paper presents a new dynamic finite-state vector quantization (DFSVQ) algorithm which provides better quality than the best quality that the supercodebook can offer. The new DFSVQ exploits the global interblock correlation of image blocks instead of local correlation in conventional DFSVQs. For an input block, we search the closest block from the previously encoded data using the side-match technique. The closest block is then used as the prediction of the input block, or used to generate a dynamic codebook. The input block is encoded by the closest block, dynamic codebook or supercodebook. Searching for the closest block from the previously encoded data is equivalent to expand the codevector space; thus the picture quality achieved is not limited by the supercodebook. Experimental results reveal that the new DFSVQ reduces bit rate significantly and provides better visual quality, as compared to the basic VQ and other DFSVQs.
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Affiliation(s)
- J C Tsai
- Dept. of Electr. Eng., Chinese Army Acad., Kaohsiung
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Khoury JM, Donahue SP, Lavin PJ, Tsai JC. Comparison of 24-2 and 30-2 perimetry in glaucomatous and nonglaucomatous optic neuropathies. J Neuroophthalmol 1999; 19:100-8. [PMID: 10380130] [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: 02/12/2023]
Abstract
OBJECTIVE To determine whether the 24-2 Humphrey visual field (HVF) (Humphrey, San Leandro, CA) strategy provides information comparable to that provided by the 30-2 strategy in patients with optic nerve disease. METHODS In part A of the study, an occluder device was designed to cover the additional outer 22 points tested in the 30-2 strategy of 187 HVFs from neuro-ophthalmology patients with nonglaucomatous optic neuropathy and 206 HVFs from patients with glaucoma. This device converted the gray scale and probability plots of the 30-2 HVF to a 24-2 field. Fields were initially read using the occluder and then were read in a masked manner without the occluder and compared. In part B, 15 healthy volunteers performed both 30-2 and 24-2 HVFs. Testing time and global indices were compared. Ninety-five percent of the fields in the neuro-ophthalmology patients, 96% of the fields in patients under observation for suspected glaucoma, 98% of the fields in patients with ocular hypertension, and 100% of the fields in patients with glaucoma were read similarly with the 24-2 and 30-2 strategies. In the few cases in which a discrepancy was noted between the 24-2 and the 30-2 fields, appropriate clinical management would not have been compromised by using the 24-2 strategy. Most of these cases were in patients with idiopathic intracranial hypertension and very subtle nerve fiber bundle defects. The 24-2 strategy had a significantly lower pattern standard deviation (P < 0.01) and corrected pattern standard deviation (P = 0.05) than did the 30-2 strategy. In addition, the 24-2 strategy shortened the standard threshold testing time by 28% in normal volunteers (P < 0.0001 ). CONCLUSIONS In most cases, the 24-2 testing strategy provides information comparable to that provided by the 30-2 strategy in a shorter time and with less variability. A 30-2 HVF may be warranted in patients under observation for evolving idiopathic intracranial hypertension.
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Affiliation(s)
- J M Khoury
- Department of Ophthalmology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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Chang JM, Hwang SJ, Tsai JC, Chen HC, Guh JY, Lai YH. Effect of ferric polymaltose complex as a phosphate binder in haemodialysis patients. Nephrol Dial Transplant 1999; 14:1045-7. [PMID: 10328515 DOI: 10.1093/ndt/14.4.1045] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Sheu HM, Chao SC, Wong TW, Yu-Yun Lee J, Tsai JC. Human skin surface lipid film: an ultrastructural study and interaction with corneocytes and intercellular lipid lamellae of the stratum corneum. Br J Dermatol 1999; 140:385-91. [PMID: 10233255 DOI: 10.1046/j.1365-2133.1999.02697.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [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: 11/20/2022]
Abstract
Sebum is a complex mixture of lipids, which is secreted by mammalian sebaceous glands, and forms a fluid film over the skin surface. After sebum is secreted, it becomes mixed with lipid from the keratinizing epithelium and forms the skin surface lipid film (SSLF). Until now, direct fine structural observation of the SSLF has been lacking. In the present work, we viewed the detailed structures of the human SSLF by ruthenium tetroxide staining. The results showed that the SSLF formed an amorphous sheet of variable thickness on the skin surface instead of forming lipid droplets, as had been the usual assumption. In general, its thickness was < 0.5 microm or even negligible in sebum-poor extremities. However, in the sebum-rich face, its thickness was > 4 microm in focal areas. Consistent with the thickness of SSLF, the sebum quantity showed great regional variation. It varied from 1 microg/cm2 (leg) to 189 +/- 42.7 microg/cm2 (mean +/- SD: face). The SSLF was composed of numerous fine granules of about 4-5 nm in a random orientation. Within the SSLF, variable amounts of deranged lipid lamellae derived from corneocytes were mixed with sebum. As well as on the skin surface, a similar amount of sebum was also found between the desquamating corneocytes in the uppermost several layers of the stratum corneum (SC). We also observed the presence of intercellular lipid lamellae in the outer layers of the SC: their lipid envelope remained intact even in desquamated corneocytes. Our results provide some new insights concerning the structure of the SSLF and its relationship with the SC.
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Affiliation(s)
- H M Sheu
- Department of Dermatology, National Cheng-Kung University Hospital, Taiwan
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