1.Treatment of thoracolumbar burst fractures with bioactive artificial vertebrae of nano-hydroxyapatite and polymide 66
Dian-Ming JIANG ; Zheng-Xue QUAN ; Yun-Sheng OU ; Wei-Dong NI ; Xi LIANG ; Chun-Yang MENG
Chinese Journal of Trauma 2003;0(12):-
Objective To investigate the efficacy of the bioactive artificial vertebrae of a nano- hydroapatite crystals and polyamide 66 composite(n-HA/PA66)to restore the height and architecture of thoracolumbar burst fracture.Methods From December 2003 to February 2006,38 patients(29 males and 9 females)with a mean age of 35.6 years(17-63 years)were treated surgically through anterior ap- proach for decompression and implanted with the bioactive artificial vertebrae of n-HA/PA66 composite to reconstruct the structure of the thoracolumbar burst fractured vertebra.Results All the patients were successfuly followed-up for an average of 8 months,ranging from 6 to 21 months.The bioaetive artificial vertebrac of n-HA/PA66 composite were fused with the receptor bone 3-4 months after operation.The neu- rological function of the patients was restored partially or completely.The thoracolumbar spine was stable during physical examination and the height of thoraeolumbar burst fractured vertebrae that had been restored did not changa during the follow-up.Conclusions Our results show the bioaetive artificial vertebrae of n-HA/PA66 can restore the height and structure of thoracolumbar burst fractured vertebrae and reconstruct the structure of the tboraeolumbar vertebrae effectively,indicating that the bioaetive artificial vertebrae of n- HA/PA66 can be used extensively in clinical spinal surgery.
2.Effect of influenza-like diseases on the number of outpatient visits.
Chun-quan OU ; Zhuo-hui DENG ; Lin YANG ; Ping-yan CHEN
Journal of Southern Medical University 2008;28(8):1446-1448
OBJECTIVETo estimate the effect of influenza-like illness (ILI) on outpatient visits and assess its impact on public health.
METHODSWe analyzed the data of weekly number of ILI and outpatient visits in Departments of Internal Medicine, Pediatrics and Emergency at two influenza surveillance hospitals during a period of 137 weeks in Guangzhou. Spectral analysis and time-series analysis were performed to evaluate the variation of outpatient visits over time. The predictive model was fitted with weekly outpatient visits as the dependent variable and weekly number of ILI as the independent variable. The optimal model was established according to the coefficient of determination, Akaike-information criterion and residual analysis. The validity of the model was assessed prospectively using the 31-week data that were not used for the model establishment.
RESULTSThe outpatient visits increased significantly over time and showed significant seasonality (P<0.001). A significant correlation was found between the weekly number of ILI and outpatient visits (r=0.568, P<0.001). The residuals of the fitted autoregression model were white-noise series and the coefficient of determination was 75% for the data used to establish the model and 56% for the subsequent 31-week data.
CONCLUSIONSThe autoregression model can be used to estimate the effect of weekly number of outpatient visits based on the weekly number of ILI and thus assess the effects of influenza on public health.
Child ; China ; epidemiology ; Emergency Service, Hospital ; statistics & numerical data ; Humans ; Influenza, Human ; epidemiology ; Logistic Models ; Outpatient Clinics, Hospital ; statistics & numerical data ; Outpatients ; statistics & numerical data
3.Impact of heat wave in 2005 on mortality in Guangzhou, China.
Jun YANG ; Hua Zhang LIU ; Chun Quan OU ; Guo Zhen LIN ; Yan DING ; Qin ZHOU ; Ji Chuan SHEN ; Ping Yan CHEN
Biomedical and Environmental Sciences 2013;26(8):647-654
OBJECTIVETo assess the impact of the heat wave in 2005 on mortality among the residents in Guangzhou and to identify susceptible subpopulations in Guangzhou, China.
METHODSThe data of daily number of deaths and meteorological measures from 2003 to 2006 in Guangzhou were used in this study. Heat wave was defined as ⋝7 consecutive days with daily maximum temperature above 35.0 °C and daily mean temperature above the 97th percentile during the study period. The excess deaths and rate ratio (RR) of mortality in the case period compared with the reference period in the same summer were calculated.
RESULTSDuring the study period, only one heat wave in 2005 was identified and the total number of excess deaths was 145 with an average of 12 deaths per day. The effect of the heat wave on non-accidental mortality (RR=1.23, 95% CI: 1.11-1.37) was found with statistically significant difference. Also, greater effects were observed for cardiovascular mortality (RR=1.34, 95% CI: 1.13-1.59) and respiratory mortality (RR=1.31, 95% CI: 1.02-1.69). Females, the elderly and people with lower socioeconomic status were at significantly higher risk of heat wave-associated mortality.
CONCLUSIONThe 2005 heat wave had a substantial impact on mortality among the residents in Guangzhou, particularly among some susceptible subpopulations. The findings from the present study may provide scientific evidences to develop relevant public health policies and prevention measures aimed at reduction of preventable mortality from heat waves.
Adolescent ; Adult ; Aged ; Child ; Child, Preschool ; China ; epidemiology ; Female ; History, 21st Century ; Hot Temperature ; Humans ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Mortality ; Weather ; Young Adult
4.The impact of relative humidity and atmospheric pressure on mortality in Guangzhou, China.
Chun Quan OU ; Jun YANG ; Qiao Qun OU ; Hua Zhang LIU ; Guo Zhen LIN ; Ping Yan CHEN ; Jun QIAN ; Yu Ming GUO
Biomedical and Environmental Sciences 2014;27(12):917-925
OBJECTIVEAlthough many studies have examined the effects of ambient temperatures on mortality, little evidence is on health impacts of atmospheric pressure and relative humidity. This study aimed to assess the impacts of atmospheric pressure and relative humidity on mortality in Guangzhou, China.
METHODSThis study included 213,737 registered deaths during 2003-2011 in Guangzhou, China. A quasi-Poisson regression with a distributed lag non-linear model was used to assess the effects of atmospheric pressure/relative humidity.
RESULTSWe found significant effect of low atmospheric pressure/relative humidity on mortality. There was a 1.79% (95% confidence interval: 0.38%-3.22%) increase in non-accidental mortality and a 2.27% (0.07%-4.51%) increase in cardiovascular mortality comparing the 5th and 25th percentile of atmospheric pressure. A 3.97% (0.67%-7.39%) increase in cardiovascular mortality was also observed comparing the 5th and 25th percentile of relative humidity. Women were more vulnerable to decrease in atmospheric pressure and relative humidity than men. Age and education attainment were also potential effect modifiers. Furthermore, low atmospheric pressure and relative humidity increased temperature-related mortality.
CONCLUSIONBoth low atmospheric pressure and relative humidity are important risk factors of mortality. Our findings would be helpful to develop health risk assessment and climate policy interventions that would better protect vulnerable subgroups of the population.
Adolescent ; Adult ; Aged ; Atmospheric Pressure ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Humidity ; Infant ; Male ; Middle Aged ; Mortality ; Young Adult
5.The Impacts of Mosquito Density and Meteorological Factors on Dengue Fever Epidemics in Guangzhou, China, 2006-2014: a Time-series Analysis.
Ji Chuan SHEN ; Lei LUO ; Li LI ; Qin Long JING ; Chun Quan OU ; Zhi Cong YANG ; Xiao Guang CHEN
Biomedical and Environmental Sciences 2015;28(5):321-329
OBJECTIVETo explore the associations between the monthly number of dengue fever(DF) cases and possible risk factors in Guangzhou, a subtropical city of China.
METHODSThe monthly number of DF cases, Breteau Index (BI), and meteorological measures during 2006-2014 recorded in Guangzhou, China, were assessed. A negative binomial regression model was used to evaluate the relationships between BI, meteorological factors, and the monthly number of DF cases.
RESULTSA total of 39,697 DF cases were detected in Guangzhou during the study period. DF incidence presented an obvious seasonal pattern, with most cases occurring from June to November. The current month's BI, average temperature (Tave), previous month's minimum temperature (Tmin), and Tave were positively associated with DF incidence. A threshold of 18.25 °C was found in the relationship between the current month's Tmin and DF incidence.
CONCLUSIONMosquito density, Tave, and Tmin play a critical role in DF transmission in Guangzhou. These findings could be useful in the development of a DF early warning system and assist in effective control and prevention strategies in the DF epidemic.
Animals ; China ; epidemiology ; Culicidae ; physiology ; Dengue ; epidemiology ; Epidemics ; statistics & numerical data ; Humans ; Population Density ; Time Factors ; Weather