1.Scanning laser polarimetry in pulmonary tuberculosis patients on chemotherapy.
Wilson W T TANG ; Jimmy S M LAI ; Clement C Y THAM ; Kam-Keung CHAN ; Kin-Sang CHAN
Annals of the Academy of Medicine, Singapore 2006;35(6):395-399
INTRODUCTIONThe aim of this study was to analyse the thickness of the retinal nerve fibre layer (RNFL) of pulmonary tuberculosis patients on ethambutol and isoniazid.
MATERIALS AND METHODSThis was a prospective cohort study where patients with newly diagnosed pulmonary tuberculosis requiring chemotherapy, including ethambutol and isoniazid, were imaged using scanning laser polarimetry. Their mean baseline RNFL thickness and various scanning laser polarimetry parameters of both eyes were measured 2 weeks after the commencement of chemotherapy. The measurements were repeated at 3 months and 6 months after treatment. The various parameters of the baseline and the follow-up measurements were compared using paired sample t-test with Bonferroni correction.
RESULTSTwenty-four patients (16 males and 8 females; mean age, 51.0 +/- 17.6 years) were recruited. There was no statistically significant difference between the baseline and the follow-up measurements in RNFL thickness and all other scanning laser polarimetry parameters.
CONCLUSIONIn this cohort of subjects, there was no subclinical change in RNFL thickness detected by scanning laser polarimetry in pulmonary tuberculosis patients on chemotherapy, including ethambutol and isoniazid, after 6 months of treatment.
Adult ; Aged ; Aged, 80 and over ; Antitubercular Agents ; adverse effects ; therapeutic use ; Diagnostic Techniques, Ophthalmological ; Ethambutol ; adverse effects ; therapeutic use ; Female ; Humans ; Isoniazid ; adverse effects ; therapeutic use ; Lasers ; Male ; Middle Aged ; Prospective Studies ; Retinal Diseases ; chemically induced ; diagnosis ; Tuberculosis, Pulmonary ; drug therapy
2.Pattern and outcome of subsidised referrals to cardiology specialist outpatient clinics.
Bernard W K KWOK ; Hak Chiaw TANG ; Shiou Liang WEE ; Virginia U M TAI ; Caren G P TAN ; Terrance S J CHUA
Annals of the Academy of Medicine, Singapore 2008;37(2):103-108
INTRODUCTIONIncreasing demand for public healthcare and access to specialist care has become a major concern. Characterising the referral pattern to a national centre's cardiology specialist outpatient clinics (SOCs) and the diagnostic outcomes may be useful in formulating referral guidelines to contain rising demand.
MATERIALS AND METHODSA prospective observational followup study was conducted of all consecutive new patient referrals to the cardiology SOCs of the National Heart Centre over a 1-month period. The records of these 1224 patients were reviewed following their first visit and again after 3 months of evaluation and investigation. Patients' demographics, referral sources, indications of referral, risk factors, provisional and final diagnoses were collected. Referrals from the top 2 volume sources (government polyclinics and hospital Emergency Department) accounted for 600 referrals. These subsidised referrals formed the study group for analysis.
RESULTSThe mean age of referred patients was 56 +/- 15.2 years, with equal proportion of males and females. Most patients had known cardiac risk factors of hypertension (53.2%) and hyperlipidaemia (42.3%). Only 23% of referrals had significant cardiac abnormalities. Referrals for typical chest pain derived the highest yield whereas referrals for atypical chest pain, non-cardiac chest pain derived the lowest yield. Referrals for asymptomatic electrocardiogram (ECG) changes (except for atrial flutter/fibrillation) did not yield cardiac abnormalities. Multivariate analysis of chest pain referrals showed typical chest pain and hyperlipidaemia to be statistically significant predictors for coronary artery disease.
CONCLUSIONReferrals to cardiology outpatient specialist clinics should be based on the presence of patient symptoms, particularly that of typical chest pain. In asymptomatic patients, routine ECG screening did not appear to yield significant cardiac abnormalities.
Adult ; Aged ; Ambulatory Care Facilities ; Cardiology ; Cardiovascular Diseases ; diagnosis ; physiopathology ; Female ; Health Services Needs and Demand ; Humans ; Male ; Medicine ; Middle Aged ; Prospective Studies ; Referral and Consultation ; economics ; utilization ; Singapore ; Specialization
3.Tracking the emergence of pandemic Influenza A/H1N1/2009 and its interaction with seasonal influenza viruses in Singapore.
Julian W T TANG ; Chun Kiat LEE ; Hong Kai LEE ; Tze Ping LOH ; Lily CHIU ; Paul A TAMBYAH ; Evelyn S C KOAY
Annals of the Academy of Medicine, Singapore 2010;39(4):291-294
INTRODUCTIONSince the emergence of the pandemic influenza A/H1N1/2009 virus in April 2009, diagnostic testing in many countries has revealed the rapid displacement and then replacement of circulating seasonal influenza viruses by this novel virus.
MATERIALS AND METHODSIn-house seasonal and pandemic influenza-specific polymerase chain reaction assays were introduced and/or developed at the Molecular Diagnosis Centre (MDC) at the National University Hospital (NUH), Singapore. These assays have been used to test all samples received from in-patients, out-patients, staff and visitors for suspected pandemic influenza A/H1N1/2009 infection.
RESULTSPrior to the arrival of the pandemic A/H1N1/2009 virus in Singapore at the end of May 2009, seasonal influenza A/H3N2 predominated in this population, with very little seasonal influenza A/H1N1 and B viruses detected. Within about 1 month of its arrival in Singapore (mainly during June to July 2009), this pandemic virus rapidly displaced seasonal influenza A/H3N2 to become the predominant strain in the Singaporean population served by MDC/NUH.
CONCLUSIONSRealtime molecular techniques have allowed the prompt detection of different influenza subtypes during this current pandemic, which has revealed the displacement/replacement of previously circulating seasonal subtypes with A/H1N1/2009. Although some of this may be explained by immunological cross-reactivity between influenza subtypes, more studies are required.
Communicable Diseases, Emerging ; Cross Reactions ; Disease Outbreaks ; Humans ; Influenza A Virus, H1N1 Subtype ; isolation & purification ; Influenza B virus ; isolation & purification ; Influenza, Human ; classification ; diagnosis ; epidemiology ; Influenzavirus C ; isolation & purification ; Molecular Diagnostic Techniques ; Polymerase Chain Reaction ; Singapore ; epidemiology
4.Genetic characteristics of hemagglutinin and neuraminidase of avian influenza A (H7N9) virus in Guizhou province, 2014-2017.
Y H WAN ; L ZHUANG ; Q N ZHENG ; L J REN ; L FU ; W J JIANG ; G P TANG ; D Z ZHANG ; S J LI
Chinese Journal of Epidemiology 2018;39(11):1465-1471
Objective: To understand the molecular characteristics of hemagglutinin (HA) and neuraminidase (NA) as well as the disease risk of influenza virus A H7N9 in Guizhou province. Methods: RNAs were extracted and sequenced from HA and NA genes of H7N9 virus strains obtained from 18 cases of human infection with H7N9 virus and 6 environmental swabs in Guizhou province during 2014-2017. Then the variation and the genetic evolution of the virus were analyzed by using a series of bioinformatics software package. Results: Homology analysis of HA and NA genes revealed that 2 strains detected during 2014-2015 shared 98.8%-99.2% and 99.2% similarities with vaccine strains A/Shanghai/2/2013 and A/Anhui/1/2013 recommended by WHO, respectively. Two strains detected in 2016 and 14 strains detected in 2017 shared 98.2%-99.3% and 97.6%-98.8% similarities with vaccine strain A/Hunan/02650/2016, respectively. Other 6 stains detected in 2017 shared 99.1%-99.4% and 98.9%-99.3% similarities with strain A/Guangdong/17SF003/2016, respectively. Phylogenetic analysis showed that all the strains were directly evolved in the Yangtze River Delta evolution branch, but they were derived from different small branch. PEVPKRKRTAR↓GLF was found in 6 of 24 strains cleavage site sequences of HA protein, indicating the characteristic of highly pathogenic avian influenza virus. Mutations A134V, G186V and Q226L at the receptor binding sites were found in the HA. All the strains had a stalk deletion of 5 amino acid residue "QISNT" in NA protein, and drug resistance mutation R294K occurred in strain A/Guizhou-Danzhai/18980/2017. In addition, potential glycosylation motifs mutations NCS42NCT were found in the NA of 9 of 24 strains. Conclusions: HA and NA genes of avian influenza A (H7N9) virus showed genetic divergence in Guizhou province during 2014-2017. The mutations of key sites might enhance the virulence of the virus, human beings are more susceptible to it. Hence, the risk of infection is increasing.
Animals
;
Base Sequence
;
Birds
;
China/epidemiology*
;
Genome, Viral
;
Hemagglutinin Glycoproteins, Influenza Virus/immunology*
;
Hemagglutinins/genetics*
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Humans
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Influenza A Virus, H7N9 Subtype/isolation & purification*
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Influenza in Birds
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Influenza, Human/virology*
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Neuraminidase/genetics*
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Phylogeny
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RNA, Viral/genetics*
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Sequence Analysis, DNA
5.Survivorship Analysis in Asymptomatic COVID-19+ Hip Fracture Patients: Is There an Increase in Mortality?
Mason D. VIALONGA ; Luke G. MENKEN ; Alex TANG ; John W. YUREK ; Li SUN ; John J. FELDMAN ; Frank A. LIPORACE ; Richard S. YOON
Hip & Pelvis 2022;34(1):25-34
Purpose:
Mortality rates following hip fracture surgery have been well-studied. This study was conducted to examine mortality rates in asymptomatic patients presenting for treatment of acute hip fractures with concurrent positive COVID-19(+) tests compared to those with negative COVID-19(–) tests.
Materials and Methods:
A total of 149 consecutive patients undergoing hip fracture surgery during the COVID-19 pandemic at two academic medical centers were reviewed retrospectively. Patients were divided into two groups for comparative analysis: one group included asymptomatic patients with COVID-19+ tests versus COVID-19– tests. The primary outcome was mortality at 30-days and 90-days.
Results:
COVID-19+ patients had a higher mortality rate than COVID-19– patients at 30-days (26.7% vs 6.0%, P=0.005) and 90-days (41.7% vs 17.2%, P=0.046) and trended towards an increased length of hospital stay (10.1 ±6.2 vs 6.8±3.8 days, P=0.06). COVID-19+ patients had more pre-existing respiratory disease (46.7% vs 11.2%,P=0.0002). Results of a Cox regression analysis showed an increased risk of mortality at 30-days and 90-days from COVID-19+ status alone without an increased risk of death in patients with pre-existing chronic respiratory disease.
Conclusion
Factors including time to surgery, age, preexisting comorbidities, and postoperative ambulatory status have been proven to affect mortality and complications in hip fracture patients; however, a positive COVID-19 test result adds another variable to this process. Implementation of protocols that will promote prompt orthogeriatric assessments, expedite patient transfer, limit operating room traffic, and optimize anesthesia time can preserve the standard of care in this unique patient population.
6.Melatonin Attenuates Noise Stress-induced Gastrointestinal Motility Disorder and Gastric Stress Ulcer: Role of Gastrointestinal Hormones and Oxidative Stress in Rats.
Lei ZHANG ; Ji T GONG ; Hu Q ZHANG ; Quan H SONG ; Guang H XU ; Lei CAI ; Xiao D TANG ; Hai F ZHANG ; Fang E LIU ; Zhan S JIA ; Hong W ZHANG
Journal of Neurogastroenterology and Motility 2015;21(2):189-199
BACKGROUND/AIMS: There are increasing evidences for gastrointestinal motility disorder (GIMD) and gastric stress ulcer induced by noise stress. The present study was to investigate the reversed effect of melatonin on GIMD and gastric stress ulcer induced by noise stress and potential mechanism. METHODS: Noise stress was induced on rats, and melatonin (15 mg/kg) was administered to rats by intraperitoneal injection. Differences were assessed in gastric residual rate (GRR), small intestine propulsion rate (SPR), Guth injury score, cortisol, gastrointestinal hormones (calcitonin-gene-related peptide and motilin) and oxidative stress markers (superoxide dismutase and malondialde hyde) in blood plasma as well as gastric mucosa homogenate with or without melatonin. The pathological examination of gastric mucosa was also performed. RESULTS: The GRR and SPR were improved by noise stress compared with control (P < 0.05). The pathological examination and Guth injury score revealed gastric stress ulcer. Moreover, the levels of cortisol, motilin and malondialdehyde in blood plasma and malondialdehyde in gastric mucosa homogenate were increased by noise stress (P < 0.05). CGRP and superoxide dismutase activity in both of blood plasma and gastric mucosa homogenate were significantly decreased (P< 0.05). Furthermore, melatonin reversed changes in GRR, SPR, pathological examination, Guth injury score, cortisol, motilin, CGRP, superoxide dismutase activity and malondialdehyde (P < 0.05). CONCLUSIONS: Melatonin is effective in reversing the GIMD and gastric stress ulcer induced by noise stress. The underlying mechanism may be involved in oxidative stress and gastrointestinal hormones.
Animals
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Gastric Mucosa
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Gastrointestinal Hormones*
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Gastrointestinal Motility*
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Hydrocortisone
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Injections, Intraperitoneal
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Intestine, Small
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Malondialdehyde
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Melatonin*
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Motilin
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Noise*
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Oxidative Stress*
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Plasma
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Rats*
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Superoxide Dismutase
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Ulcer*
7.Risk of bias assessment: (7) Assessing Bias in Studies of Prognostic Factors.
S W TANG ; Y ZHANG ; B L TAO ; Z R YANG ; F SUN ; S Y ZHAN
Chinese Journal of Epidemiology 2018;39(7):1003-1008
This paper introduces the tools related to Quality In Prognosis Studies (QUIPS) to assess the risk of bias in studies of prognostic factors and the relevant points of assessment and to illustrate the application of QUIPS in published prognostic research. The QUIPS tool identified 6 important areas to consider when evaluating validity and bias in studies of prognostic factors including participation, attrition, measurement on prognostic factors, outcomes, confounding factors, statistical analysis and reporting. It also provided a new method for evaluation on bias in the areas of prognostic research.
Bias
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Humans
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Prognosis
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Quality Improvement
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Research Design
8.Seasonal distribution of patient hospitalization due to asthma exacerbation in 7 geographic areas in China.
J T LIN ; B XING ; H P TANG ; L YANG ; Y D YUAN ; Y H GU ; P CHEN ; X J LIU ; J ZHANG ; H G LIU ; C Z WANG ; W ZHOU ; D J SUN ; Y Q CHEN ; Z C CHEN ; M HUANG ; Q C LIN ; C P HU ; X H YANG ; J M HUO ; X W YE ; X ZHOU ; P JIANG ; W ZHANG ; Y J HUANG ; L M DAI ; R Y LIU ; S X CAI ; J Y XU ; J Y ZHOU
Chinese Journal of Epidemiology 2018;39(11):1477-1481
Objective: To understand the seasonal distribution of patient hospitalization due to asthma exacerbation in 7 geographic areas in China. Methods: This was a retrospective study which involved patients hospitalized for asthma exacerbation in 29 hospitals throughout 7 geographic areas in the mainland of China (northeast, north, central, east, south, northwest and southwest). The numbers of asthmatic patients and total inpatients of the respiratory department of each hospital were recorded. The monthly ratio of asthmatic patients to the total inpatients in every area was calculated and compared. Results: During the study period, 6 480 patients were admitted for asthma exacerbation, accounting for 3.14% of all the 206 135 patients admitted to the respiratory departments in the 29 hospitals. The ratio of asthmatic patients to total inpatients in the northeast area (5.61%) was highest, and the ratio in east area was lowest (1.97%). Statistical analysis showed that the difference among different areas was significant (P<0.000 1). In most areas, both the number and proportion of hospitalized asthmatic patients peaked in spring (February-April) and autumn (September-October). In the northeast area, east area and south area, the peaks in spring were more obvious, while in the north area and southwest area, the peaks in autumn were more obvious. In the northwest area the peaks occurred in winter (December-January) and summer (June-August), respectively. The differences in hospitalization due to asthma among different months were significant in the northeast, north, and southwest areas (P<0.005). Conclusion: The number of patients hospitalized for asthma exacerbation fluctuated with season in different areas in China. In most areas, more asthmatic patients were admitted to hospitals in spring and autumn.
Asthma
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China/epidemiology*
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Hospitalization/statistics & numerical data*
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Humans
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Retrospective Studies
;
Seasons
9.Cost-effectiveness of lung cancer screening worldwide: a systematic review.
C C LIU ; J F SHI ; G X LIU ; W TANG ; X ZHANG ; F LI ; L WANG ; Y MA ; K SU ; S J ZHAO ; Y B GAO ; N LI ; W Q CHEN ; N WU ; M DAI
Chinese Journal of Epidemiology 2019;40(2):218-226
Objective: From the economic point of view, this study was to systematically assess the status quo on lung cancer screening in the world and to provide reference for further research and implementation of the programs, in China. Methods: PubMed, EMbase, The Cochrane Library,CNKI and Wanfang Data were searched to gather papers on studies related to economic evaluation regarding lung cancer screening worldwide, from the inception of studies to June 30(th), 2018. Basic characteristics, methods and main results were extracted. Quality of studies was assessed. Cost were converted to Chinese Yuan under the exchange rates from the World Bank. The ratio of incremental cost-effectiveness ratio (ICER) to local GDP per capita were calculated. Results: A total of 23 studies (only 1 randomized controlled trial) were included and the overall quality was accepted. 22 studies were from the developed countries. Nearly half of the studies (11 studies) took 55 years old as the starting age of the screening program. Smoking history was widely applied for the selection of criteria on target populations (18). Low-dose computed tomography (LDCT) was involved in every study used to evaluate the economic effectiveness. Annual (17) and once-life time (7) screening were more common frequencies. 22 studies reported ICERs for LDCT screening, compared to no screening, of which 17 were less than 3 times local GDP per capita, and were considered as cost-effectiveness, according to the WHO's recommendation. 15 and 7 studies reported ICERs for annual and once-life time screening, of which 12 and 7 studies were in favor the results of their cost-effectiveness, respectively. Additionally, the cost-effectiveness of once-lifetime screening was likely to be superior to the annual screening. Differences of cost-effectiveness among the subgroups, by starting age or by the smoking history, might exist. Conclusions: Based on the studies, evidence from the developed countries demonstrated that LDCT screening programs on lung cancer, implemented among populations selected by age and smoking history, generally appeared more cost-effective. Combined with the local situation of health resource, the findings could provide direction for less developed regions/countries lacking of local evidence. Low frequency of LDCT screening for lung cancer could be adopted when budget was limited. Data on starting ages, smoking history and other important components related to the strategy of screening programs, needs to be precisely evaluated under the situation of local population.
China
;
Cost-Benefit Analysis
;
Early Detection of Cancer/methods*
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Humans
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Lung Neoplasms/prevention & control*
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Middle Aged
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Quality-Adjusted Life Years
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Randomized Controlled Trials as Topic