3.Developing the "NUS Tummy Dummy", a low-cost simulator to teach medical students to perform the abdominal examination.
Shariff MAHABOOB ; Lian-Kiat LIM ; Chew-Lip NG ; Quan-Yao HO ; Michael E L LEOW ; Erle C H LIM
Annals of the Academy of Medicine, Singapore 2010;39(2):150-151
Abdomen
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physiology
;
Humans
;
Manikins
;
Physical Examination
;
methods
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Singapore
;
Students, Medical
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Teaching
;
methods
4.Scrotal aggressive angiomyxoma mimicking inguinal hernia.
Chia-Chang WU ; Stephen Shei-Dei YANG ; Daniel T H CHIN ; Cheng-Hsing HSIEH ; Yu-Mei HSUEH ; Yao-Chou TSAI
Asian Journal of Andrology 2007;9(5):723-725
Adult
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Diagnosis, Differential
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Genital Neoplasms, Male
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pathology
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surgery
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Hernia, Inguinal
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pathology
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Humans
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Male
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Myxoma
;
pathology
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surgery
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Scrotum
;
pathology
5.Neural stem cells: mechanisms and modeling.
Jun YAO ; Yangling MU ; Fred H GAGE
Protein & Cell 2012;3(4):251-261
In the adult brain, neural stem cells have been found in two major niches: the dentate gyrus and the subventricular zone [corrected]. Neurons derived from these stem cells contribute to learning, memory, and the autonomous repair of the brain under pathological conditions. Hence, the physiology of adult neural stem cells has become a significant component of research on synaptic plasticity and neuronal disorders. In addition, the recently developed induced pluripotent stem cell technique provides a powerful tool for researchers engaged in the pathological and pharmacological study of neuronal disorders. In this review, we briefly summarize the research progress in neural stem cells in the adult brain and in the neuropathological application of the induced pluripotent stem cell technique.
Hippocampus
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cytology
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metabolism
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Humans
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Induced Pluripotent Stem Cells
;
cytology
;
metabolism
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Models, Biological
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Neural Stem Cells
;
cytology
;
metabolism
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transplantation
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Neurodegenerative Diseases
;
metabolism
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pathology
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prevention & control
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Neurogenesis
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Signal Transduction
6.FAMCS: Finding All Maximal Common Substructures in Proteins
Yao ZHEN ; Xiao JUAN ; Anthony K. H. Tung ; Sung Kin WING
Genomics, Proteomics & Bioinformatics 2005;3(2):107-119
Finding the common substructures shared by two proteins is considered as one of the central issues in computational biology because of its usefulness in understanding the structure-function relationship and application in drug and vaccine design.In this paper, we propose a novel algorithm called FAMCS (Finding All Maximal Common Substructures) for the common substructure identification problem. Our method works initially at the protein secondary structural element (SSE) level and starts with the identification of all structurally similar SSE pairs. These SSE pairs are then merged into sets using a modified Apriori algorithm, which will test the similarity of various sets of SSE pairs incrementally until all the maximal sets of SSE pairs that deemed to be similar are found. The maximal common substructures of the two proteins will be formed from these maximal sets. A refinement algorithm is also proposed to fine tune the alignment from the SSE level to the residue level.Comparison of FAMCS with other methods on various proteins shows that FAMCS can address all four requirements and infer interesting biological discoveries.
7.Antioxidative and anti-endotoxin effects of propofol on endothelial cells.
Zhiyong PENG ; Min LUO ; Shiqiao YE ; Lester A H CRITCHLEY ; Gavin M JOYNT ; Anthony M H HO ; Shanglong YAO
Chinese Medical Journal 2003;116(5):731-735
OBJECTIVETo investigate the antioxidant and anti-endotoxin effects of propofol on endothelial cells and the possible mechanisms.
METHODSCultured endothelial cells were treated with hydrogen peroxide (H(2)O(2)), propofol + H(2)O(2), lipopolysaccharide (LPS) and propofol + LPS, respectively. Endothelial cell damage was monitored for possible lactic dehydrogenase (LDH) release. The transcription and the protein expression levels of endothelial nitric oxide synthase (eNOS) were measured.
RESULTSLDH release was higher in groups treated with H(2)O(2) or LPS than in the control group. After pretreatment with propofol, the effects induced by H(2)O(2) were attenuated, but propofol did not decrease the LDH release induced by LPS. Both H(2)O(2) and LPS significantly increased the eNOS transcript levels and the increases were significantly attenuated after pretreatment with propofol. Both H(2)O(2) and LPS significantly increased the eNOS protein expression and the increase was attenuated after pretreatment with propofol.
CONCLUSIONPropofol could protect endothelial cells against oxidative stress by inhibiting eNOS transcription and protein expression, but could not antagonise endotoxin induced cell injuries.
Antioxidants ; pharmacology ; Endothelium, Vascular ; cytology ; drug effects ; metabolism ; Endotoxins ; antagonists & inhibitors ; Free Radical Scavengers ; pharmacology ; Humans ; In Vitro Techniques ; Lipopolysaccharides ; pharmacology ; Nitric Oxide ; pharmacology ; Nitric Oxide Synthase ; biosynthesis ; Nitric Oxide Synthase Type III ; Propofol ; pharmacology
8.Association of the T1270533G polymorphism in GSTM1 gene coding region with susceptibility to nasopharyngeal carcinoma in a Chinese population.
Ying HE ; Gang-qiao ZHOU ; Xin LI ; Xiao-jia DONG ; Kai-tai YAO
Journal of Southern Medical University 2009;29(1):36-39
OBJECTIVETo explore the association of T1270533G polymorphism in the glutathione S-transferase M1 (GSTM1) gene with the susceptibility to nasopharyngeal carcinoma (NPC) and clinical phenotype of NPC in Chinese population. METHDOS: The genomic DNAs were obtained from 27 Chinese subjects, and the single nucleotide polymorphism (SNP) in all the exons and relevant intron-exon boundaries of GSTM1 were determined by PCR and direct sequencing. A case-control study was performed to analyze the SNP site T1270533G (the rare allele frequency is 22.2% in Chinese population) in the coding region by means of tetra-primer amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and sequencing.
RESULTSequence analysis identified 29 SNPs in GSTM1 gene, among which 13 SNPs presented high linkage disequilibrium with each other. No obvious relations were found between the variation in the coding region T1270533G and the clinical phenotype of NPC (RR=0.170, 95% CI =0.95-0.306 for TT homozygotes).
CONCLUSIONThe missense mutation in the coding region T1270533G of GSTM1 gene that causes an amino acid change does not affect the detoxification function of GSTM1, and the T1270533G polymorphism does not have apparent relations to NPC susceptibility in Chinese subjects in Guangdong Province.
Adult ; Aged ; Base Sequence ; Carcinoma, Squamous Cell ; genetics ; China ; Female ; Genetic Predisposition to Disease ; genetics ; Glutathione Transferase ; genetics ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; Nasopharyngeal Neoplasms ; genetics ; Polymorphism, Single Nucleotide ; Young Adult
9.A Meta-analysis on the relations between short-term exposure to PM(2.5) and both mortality and related emergency visits in China.
M LI ; Y WU ; Y H TIAN ; G Y CAO ; S S YAO ; P AI ; Z HUANG ; C HUANG ; X W WANG ; Y Y CAO ; X XIANG ; J JUAN ; Y H HU
Chinese Journal of Epidemiology 2018;39(10):1394-1401
Objective: To carry out a quantitative estimate that related to the effects of short-term exposure to PM(2.5) on all-cause mortality and emergency visits in China by using the systematic review and Meta-analysis. Methods: We selected all the studies published before March 2018 from China National Knowledge Infrastructure, Wanfang database, PubMed and EMBASE and data on relative risk (RR), excess risk (ER) and their 95%CIs: appeared in these papers were extracted. According to the differences in the size or direction (heterogeneity) of the results, we computed summary estimates of the effect values using a random-effect or fixed effect model. We also conducted the subgroup analysis and Meta-analysis to have assessed the selected studies for the evidence of study bias. Results: A total of 33 original studies, indexed in databases, were identified. Among those studies, 39 sets of data on mortality and 4 sets of data on emergency were valid to show that within the daily concentration range from 47.7 to 176.7 μg/m(3), for 10 μg/m(3) increases in PM(2.5) concentrations, it would increase the daily numbers of deaths by 0.49% (95%CI: 0.39%-0.59%) and 0.30% (95%CI: 0.10%-0.51%) for all-cause deaths and all-cause emergency-room visits, respectively. For subgroup analysis, the combined effect of PM(2.5) in causing short-term all-cause deaths in the northern areas (ER=0.42%, 95%CI: 0.30%-0.54%) seemed lower than that in the southern areas (ER=0.63%, 95%CI: 0.44%-0.82%). The combined effect of PM(2.5) concentration below 75 μg/m(3) (ER=0.50%, 95%CI: 0.37%-0.62%) was higher than that of PM(2.5) concentration ≥75 μg/m(3) (ER=0.39%, 95%CI: 0.26%-0.52%). Conclusion: Within the concentration range from 47.7 to 176.7 μg/m(3), short-term exposure to current level of PM(2.5) might increase both the all-cause daily mortality and daily emergency visits in China.
Air Pollutants
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Air Pollution/statistics & numerical data*
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China
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Databases, Factual
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Emergency Service, Hospital/statistics & numerical data*
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Environmental Exposure/statistics & numerical data*
;
Female
;
Humans
;
Male
;
Particulate Matter/toxicity*
;
Time Factors
10.Blood pressure reduction found in subjects after evolution of impaired glucose tolerance to normal glucose tolerance or diabetes——New information from The Da-Qing IGT and Diabetes Study
Yao WANG ; Jin-ping WANG ; Guang-wei LI ; Wen-ying YANG ; Ya-yun JIANG ; Xiao-yan XING ; Jing-ling ZHANG ; Jian-zhong XIAO ; Ying-hua HU ; Barbara V. Howard ; Peter H. Bennett
Chinese Journal of Endocrinology and Metabolism 2008;24(3):268-271
Objective To investigate the blood pressure change in relation to the evolution of impaired glucose tolerance (IGT). Methods From 1986 to 1992, 334 subjects with IGT were randomized to placebo, diet, exercise and diet plus exercise intervention groups. No anti-hypertension drug was given to these enrolled subjects. Blood pressure was measured at the beginning and the end of the six-year prospective study. In this analysis these subjects were stratified to seven subgroups based on 2 h plasma glucose (2hPG) level during OGTT at the end of the study: < 7.8,7.8~8.8,8.9~9.9,10.0~11.0,11.1~13.8,13.9~16.6 and≥16.7mmol/L. Blood pressure changes in relation to the evolution of glucose tolerance in these subgroups were compared by least square mean procedure. Results Changes of systolic blood pressure (SBP) in average in these seven groups were -2.4,0.6,7.7,4.3,1.7,-2.9and-6.9mm Hg (1mm Hg=0.133kPa), and changes of diastolic blood pressure (DBP) were-3.2,3.0,3.3,1.7,-0.7,-1.3 and-3.7mm Hg respectively after controlling for age, sex, BMI at baseline and Δ BMI during the follow-up period. In those subjects with IGT evolved into normal glucose tolerance (NGT) or diabetes, reductions in SBP and DBP were significantly greater than those who retained IGT with 2hPG between 8.9-9.9mmol/L (all P < 0.05 ). In 264 out of the 334 subjects with IGT and blood pressure≥130/80mm Hg at baseline, blood pressure changed more strikingly: changes of SBP in these groups were-5.2,-2.6,5.2,2.3,-2.3,-4.2,-7.6mm Hg, and DBP were -5.0, -3.7,1.5, -2.9, -4.3, - 4.0 and-6.0mm Hg respectively after the adjustment of age, sex, BMI, BMI variation. The reductions of SBP and DBP in subjects whose status of IGT was converted to NGT or diabetes were significantly greater than those with retained IGT and 2hPG between 8.9-9.9mmol/L. Conclusion Blood pressure is increased in the subjects with IGT who retained in the IGT group during the six-year follow-up period in Da-Qing Study. On the contrary, subjects with IGT evolved into NGT or diabetes demonstrate significant reduction of blood pressure.