RESUMO
Background Stroke has become a main cause of death in China. With global warming, the studies on temperature and stroke have attracted much attention. Objective To analyze he relationships between heatwave and the years of life lost (YLL) by different subtypes of stroke by controlling temporal and spatial effects with Bayesian spatio-temporal model, and to study the modifiers of the health effect of heatwave. Methods The daily information of stroke deaths, meteorological data, and air pollutant data in 40 districts and counties of Guangdong Province were collected during the warm seasons (from May to October) in the years from 2014 to 2017. The individual YLL was first calculated by matching age and gender according to the life table, and then the daily YLL rate (person-years/100 000 people) was obtained by summarizing the daily YLL and correcting it with the population of each district or county. Bayesian spatio-temporal model was used to fit a proposed exposure-response relationship between heatwave and the YLL rates of different subtypes of stroke. Finally, stratified analyses were conducted by age (<65 years, ≥65 years), gender (male, female), and region (Pearl River Delta and non-Pearl River Delta regions) to identify the major modifiers for the association between heatwave and stroke mortality. Results During the warm seasons from 2014 to 2017, a total of 23 heatwave events occurred in the 40 districts or counties of Guangdong Province, cumulatively lasting for 145 d. A total of 30 852 stroke deaths were recorded in the same time periods. The average daily YLL rate of total stroke was (2.39±3.63) person-years/100 000 people, and those for hemorrhagic stroke and ischemic stroke were (1.54±2.99) person-years/100 000 people and (0.84±1.85) person-years/100 000 people, respectively. Heatwave was associated with increased YLL rate of stroke in residents, and it had a greater impact on ischemic stroke with a lag effect. The largest cumulative effect of heatwave was at lag 0-1 day, which was associated with an increased YLL rate of total stroke and ischemic stroke by 0.17 (95%CI: 0.03-0.29) person-years/100 000 people and 0.13 (95%CI: 0.06-0.20) person-years/100 000 people, respectively. The results of stratified analyses showed that heatwave had a larger effect on ischemic stroke in residents of aged 65 years or older, male, and non-Pearl River Delta regions, and the rates of YLL increased by 1.11 (95%CI: 0.58-1.55), 0.13 (95%CI: 0.03-0.23), and 0.20 (95%CI: 0.07-0.32) person-years/100 000 people, respectively; Heatwave only had an effect on hemorrhagic stroke in residents aged 65 years or older with an increased YLL rate of 0.79 (95%CI: 0.26-1.31) person-years/100 000 people. Conclusion Heatwave could elevate the level of years of life lost associated with stroke in Guangdong residents, with greater impacts on ischemic stroke of the aged, men, and residents in non-Pearl River Delta regions, and on hemorrhagic stroke in the elderly.
RESUMO
@#Objective Zero-events studies frequently occur in systematic reviews of adverse events, which consist of an important source of evidence. We aimed to examine how evidence of zero-events studies was utilized in the meta-analyses of systematic reviews of adverse events. Methods We conducted a survey of systematic reviews published in two periods: January 1, 2015 to January 1, 2020 and January 1, 2008, to April 25, 2011. Databases were searched for systematic reviews that conducted at least one meta-analysis of any healthcare intervention and used adverse events as the exclusive outcome. An adverse event was defined as any untoward medical occurrence in a patient or subject in healthcare practice. We summarized the frequency of occurrence of zero-events studies in eligible systematic reviews and how these studies were dealt with in the meta-analyses of these systematic reviews. Results We included 640 eligible systematic reviews. There were 406 (63.45%) systematic reviews involving zero-events studies in their meta-analyses, among which 389 (95.11%) involved single-arm-zero-events studies and 223 (54.93%) involved double-arm-zero-events studies. The majority (98.71%) of these systematic reviews incorporated single-arm-zero-events studies into the meta-analyses. On the other hand, the majority (76.23%) of them excluded double-arm-zero-events studies from the meta-analyses, of which the majority (87.06%) did not discuss the potential impact of excluding such studies. Systematic reviews published at present (2015-2020) tended to incorporate zero-events studies in meta-analyses than those published in the past (2008-2011), but the difference was not significant [proportion difference=–0.09, 95%CI (–0.21, 0.03), P=0.12]. Conclusion Systematic review authors routinely treated studies with zero-events in both arms as "non-informative" carriers and excluded them from their reviews. Whether studies with no events are "informative" or not, largely depends on the methods and assumptions applied, thus sensitivity analyses using different methods should be considered in future meta-analyses.
RESUMO
ObjectivesHigh-quality meta-analyses on COVID-19 are in urgent demand for evidence-based decision making. However, conventional approaches exclude double-zero-event studies (DZS) from meta-analyses. We assessed whether including such studies impacts the conclusions in a recent systematic urgent review on prevention measures for preventing person-to-person transmission of COVID-19. Study designs and settingsWe extracted data for meta-analyses containing DZS from a recent review that assessed the effects of physical distancing, face masks, and eye protection for preventing person-to-person transmission. A bivariate generalized linear mixed model was used to re-do the meta-analyses with DZS included. We compared the synthesized relative risks (RRs) of the three prevention measures, their 95% confidence intervals (CI), and significance tests (at the level of 0.05) including and excluding DZS. ResultsThe re-analyzed COVID-19 data containing DZS involved a total of 1,784 participants who were not considered in the original review. Including DZS noticeably changed the synthesized RRs and 95% CIs of several interventions. For the meta-analysis of the effect of physical distancing, the RR of COVID-19 decreased from 0.15 (95% CI, 0.03 to 0.73) to 0.07 (95% CI, 0.01 to 0.98). For several meta-analyses, the statistical significance of the synthesized RR was changed. The RR of eye protection with a physical distance of 2 m and the RR of physical distancing when using N95 respirators were no longer statistically significant after including DZS. ConclusionsDZS may contain useful information. Sensitivity analyses that include DZS in meta-analysis are recommended.
RESUMO
BackgroundOn December 31, 2019, an outbreak of COVID-19 in humans was reported in Wuhan, and then spread fast to other provinces, China. We analyzed data from field investigations and genetic sequencing to describe the evidence and characteristics of human-to-human transmission in Guangdong Province. MethodsA confirmed COVID-19 case was defined if a suspected case was verified with positive of SARS-CoV-2 in throat swabs, nasal swabs, bronchoalveolar lavage fluid (BALF), or endotracheal aspirates by real-time reverse transcriptase polymerase chain reaction assay (RT-PCR) or genetic sequencing. Field investigations were conducted for each confirmed case. Clinical and demographic data of confirmed cases were collected from medical records. Exposure and travel history were obtained by interview. ResultsA total of 1,151 confirmed cases were identified as of February 10, 2020 in Guangdong Province, China. Of them, 697 (60.1%) cases were from 234 cluster infections. Two hundred and fourteen (18.6%) were secondary cases, in which 144 cases were from family cluster infections. With the epidemic continuing, although familial cluster events were dominated, community cluster events increased with a nosocomial event. The whole genomes within the same family cluster infections were identical, and presented a few unique single nucleotide variants (SNVs) compared with SARS-CoV-2 identified on December 2019 in Wuhan. ConclusionsWe observed evident human-to-human transmissions of SARS-CoV-2 in Guangdong, China. Although most of them were from family cluster infections, community and nosocomial infections were increasing. Our findings indicate that human-to-human transmission risks are transferring from family to community in Guangdong Province.
RESUMO
RationaleSeveral studies have estimated basic production number of novel coronavirus pneumonia (NCP). However, the time-varying transmission dynamics of NCP during the outbreak remain unclear. ObjectivesWe aimed to estimate the basic and time-varying transmission dynamics of NCP across China, and compared them with SARS. MethodsData on NCP cases by February 7, 2020 were collected from epidemiological investigations or official websites. Data on severe acute respiratory syndrome (SARS) cases in Guangdong Province, Beijing and Hong Kong during 2002-2003 were also obtained. We estimated the doubling time, basic reproduction number (R0) and time-varying reproduction number (Rt) of NCP and SARS. Measurements and main resultsAs of February 7, 2020, 34,598 NCP cases were identified in China, and daily confirmed cases decreased after February 4. The doubling time of NCP nationwide was 2.4 days which was shorter than that of SARS in Guangdong (14.3 days), Hong Kong (5.7 days) and Beijing (12.4 days). The R0 of NCP cases nationwide and in Wuhan were 4.5 and 4.4 respectively, which were higher than R0 of SARS in Guangdong (R0=2.3), Hongkong (R0=2.3), and Beijing (R0=2.6). The Rt for NCP continuously decreased especially after January 16 nationwide and in Wuhan. The R0 for secondary NCP cases in Guangdong was 0.6, and the Rt values were less than 1 during the epidemic. ConclusionsNCP may have a higher transmissibility than SARS, and the efforts of containing the outbreak are effective. However, the efforts are needed to persist in for reducing time-varying reproduction number below one. At a Glance CommentaryO_ST_ABSScientific Knowledge on the SubjectC_ST_ABSSince December 29, 2019, pneumonia infection with 2019-nCoV, now named as Novel Coronavirus Pneumonia (NCP), occurred in Wuhan, Hubei Province, China. The disease has rapidly spread from Wuhan to other areas. As a novel virus, the time-varying transmission dynamics of NCP remain unclear, and it is also important to compare it with SARS. What This Study Adds to the FieldWe compared the transmission dynamics of NCP with SARS, and found that NCP has a higher transmissibility than SARS. Time-varying production number indicates that rigorous control measures taken by governments are effective across China, and persistent efforts are needed to be taken for reducing instantaneous reproduction number below one.
RESUMO
Objective@#To estimate the incidence, mortality and characteristics of cancer in Pearl River Delta Area of Guangdong Province between 2009-2013.@*Methods@#Based on five population-based cancer registration data from Guangzhou, Shenzhen, Zhongshan, Jiangmen and Sihui spanning from 2009 to 2013, along with those corresponding population data, the incidence and mortality rates were estimated by gender and age groups. Chinese standard population derived from the 2000 Population Census and Segi′s standard population were used for age-standardized incidence and mortality rates.@*Results@#Between 2009 and 2013, the crude cancer incidence rate was 262.50/100 000, 274.76/100 000 in male and 249.49/100 000 in female. After adjusting for Chinese and Segi′s standard population, the age-standardized incidence rates were 225.63/100 000 and 219.88/100 000, respectively. The crude mortality rate was 175.51/100 000, 222.92/100 000 in male and 127.46/100 000 in female, respectively. After adjusting for Chinese and Segi′s standard population, the age-standardized mortality rates were 116.02 /100 000 and 114.31/100 000, respectively. The incidence rates were at low levels in the population less than 40 years old, thereafter went up rapidly with age especially in male, and then reached the peak in the population aged 80 and above. As with incidence, the mortality rates kept at low levels in the population before their 50 s and then rose up steadily with age until peaking in the 85+ age group. The most common cancers were female breast cancer, lung cancer, colorectal cancer, liver cancer and nasopharyngeal cancer with descending incidence rate. Lung cancer, liver cancer, colorectal cancer, female breast cancer and nasopharyngeal cancer were the top five cancer-attributable causes of death.@*Conclusions@#Currently, Pearl River Delta Area were faced with huge cancer burden. Lung cancer, colorectal cancer, nasopharyngeal cancer, female breast cancer and male liver cancer are predominant cancers and more efforts should be made to fight against them.
RESUMO
Objective To study the effect of glycine transporter 1 inhibitor M22 on epileptic sei-zures and cognitive dysfunction in epilepsy mice. Methods A total of 110 C57BL/6 mice were randomly divided into Normal control group (CON group,n=10),Model group (Mod group n=20),M22-1 group (n=20),M22-2 group (n=20),M22-3 group (n=20),M22-4 group ( n=20) according to weight. The chronic epileptic model was established by intraperitoneal injection of PTZ(30 mg/kg). The mice in CON group was injected with normal saline(10 mg/kg). The mice in Mod group were intraperitoneally injected with normal saline (10 ml/kg) and were injected with PT2 30 min later. The mice in M22-1 group,M22-2 group,M22-3 group,M22-4 group were intraperitoneally injected with M22 of corresponding dose(10 mg/kg,20 mg/kg,40 mg/kg,80 mg/kg)respectively,lasting for 2 weeks. Epilepsy seizures of mice in each group were recorded. The learning and memory function of epilepsy mice were evaluated by Morris water maze test . Then the mice were sacrificed and the apoptosis related proteins Bcl-2,Bax,Cyt-c in the cerebral cortex of mice were meas-ured by Western blot. Results (1)The mortality kindling rate,epileptic seizure grade and rate of tonic clo-nus in M22-2 and M22-3 group were significantly lower than those in Mod,M22-1 and M22-4 group( all P<0. 05). (2) In the directional navigation experiment,the escape latency of mice in each group decreased with time. On the 4th day,the escape latency of mice in M22-3 group was significantly shorter than that in Mod group,and the difference was statistically significant ((30. 24±9. 46),(16. 05±5. 72),t=20. 36,P<0. 05). In space exploration experiment,compared with Mod group,M22-3 group had more times of crossing platform ((6. 45±3. 62),(3. 23±2. 47),t=38. 63,P=0. 004) and longer time of target quadrant activity((21. 53± 6. 38) s,(11. 52±3. 15) s,t=37. 53,P<0. 05). (3)It was showed by Western blotting that the relative ex-pression levels of Bcl-2 in M22-3 group were significantly higher than those in Mod group(P<0. 05),while the Bax and Cyt-c in M22-3 group were significantly lower than those in Mod group(P<0. 05). There was no significant difference in Bcl-2, Bax and Cyt-c between M22-1 group, M22-4 group and model group ( P>0. 05). Conclusion M22 (40 mg/kg) has significant anti-epileptic effect and can effectively improve the cognitive dysfunction of epileptic mice,which may be related to the inhibition of neuronal apoptosis in mice.[Key words] Epilepsy; Glycine transporter 1 inhibitor; M22; Cognitive function; Pentyle-netetrazole
RESUMO
OBJECTIVE: To observe the early adverse effect index caused by short-term-repeated exposure to cadmium chloride via oral perfusion in male rats. METHODS: Forty specific pathogen free healthy male SD rats were randomly divided into four groups: control group,low-,middle-and high-dose groups. The rats of low-,middle-and high-dose groups were treated with cadmium chloride 1. 11,3. 51 and 11. 06 mg/kg body weight,respectively,and the control group rats was treated with the same volume of ultra pure water,by gavage once a day for four weeks. During the experimental duration,the body weights of the rats were taken and activity status of the rats was observed. After the experiment,the rats were executed,and some indicators of main organ coefficients,blood routine,serum biochemical indexes,urine related effect indexes and bone mineral density were measured. RESULTS: During the experimental duration,rats of high-dose group showed the symptoms such as decreased activity,increase repose,move slowly and skin duller. Comparing with control group at the same time points,the body masses of the high-dose group of the 1-4 weeks were lower(P < 0. 05).After the experiment,comparing with control group,the weights of kidney and spleen of the high-dose group decreased significantly(P < 0. 05) and the liver coefficient increased significantly(P < 0. 05). The cadmium levels in blood,urine,liver,kidney and thighbone of the middle-and high-dose groups were higher than those of the control group(P < 0. 05).The red blood cell counts of the low-and middle-dose groups increased significantly(P < 0. 05). The level of hemoglobin of middle-and high-dose groups decreased(P < 0. 05),and the activity of alanine aminotransferase in high-dose groups increased significantly(P < 0. 05). Comparing with control group,the levels of urine α_1-microglobulin and urine β_2-microglobulin in urine of the middle-dose group were decreased(P < 0. 05) and the level of urine urea nitrogen increased(P < 0. 05),but there were no significantly changes of the above three indexes in the high-dose group(P >0. 05). There were no significant difference of the levels of N-acetyl-beta-D glucosaminidase in urine between control and treatment groups(P > 0. 05). Simultaneously,in high-dose group,the weight of thighbone,the bone calcium content and bone mineral density reduced significantly than those of the control group(P < 0. 05). CONCLUSION: Skeletal effects can be used as an early toxic effect sensitive index of short-term-repeated experiments exposure to cadmium chloride via oral perfusion in male rats.
RESUMO
BACKGROUND:It is unclear whether serial cel passage in vitro influences the differentiation of bone marrow mesenchymal stem cel s into neural stem cel s. OBJECTIVE:To investigate the effect of cel passage on the differentiation of bone marrow mesenchymal stem cel s into neural stem cel s. METHODS:Rat bone marrow mesenchymal stem cel s were isolated and cultured by the whole bone marrow adherence method. Bone marrow mesenchymal stem cel s at passages 3, 6, 9, 12 were incubated in serum-free medium. After culture for 7 and 14 days, cel biological characterization was observed and differenitaiton ability into neural stem cel s was observed by detecting Nestin expression in cel s using flow cytometry. Then, the cel s were further induced to differentiate and cel multipotential differentiation capacity was detected by measurement of nerve enolase and glial acidic protein expression. RESULTS AND CONCLUSION:Under induction, bone marrow mesenchymal stem cel s at different passages were al differentiated into Nestin-positive neural stem cel s. However, there was a significant difference in differentiation proportion of cel s at different passages (P<0.05). Strongest differentiation ability was found in the passage 6 cel s, with the Nestin expression up to (93.7±2.3)%at 7 days of induction and (96.2±1.8)%at 14 days of induction. The proportion of differentiated cel s at passages 6 and 9 was signfi cantly higher than that at passages 3 and 12. Moreover, adherent cel s were positive for nerve enolase and glial acidic protein. Al these findings indicate that the differentiation of bone marrow mesenchymal stem cel s into neural stem cel s is correlated with cel passage. Cel s at lower or higher passages are both detrimental to cel differentiation.
RESUMO
Objective:To investigate the purification of antibacterial effective fraction of Syringae folium by macroporous resins. Methods:Static adsorption and desorption tests were carried out to screen the macroporous resins. The desorption experiment was per-formed on the selected D101 resin to optimize the separation process. The effects of resin amount, diameter length ratio, elution flow rate, elution solution concentration and volume were studied. Results:The optimal conditions were as follows:the elution solution was 55% ethanol, the adsorption flow rate was 1 BV·h-1 , the elution flow rate was 5 BV·h-1 , 6 BV 25% ethanol was used to eliminate impurity and 8 BV 55% ethanol was used to elute to obtain the effective fraction. Conclusion: The content of antibacterial effective component is above 65% after purified by D101 resin, indicating that the present method is suitable for large-scale preparation of anti-bacterial effective fraction of Syringae folium.
RESUMO
Objective:To establish the high performance liquid chromatography-fingerprints( HPLC-FPS)of Chaihu Shugan pills. Methods:The analysis was performed on a Zirchrom Kromasil C18 column with the mobile phase of methanol-water(containing 0. 05%phosphoric acid)with gradient elution at a flow-rate of 0. 8 ml·min-1 . The detection wavelength was set at 294 nm and the column temperature was 30℃. Results:With baicalin as the reference substance,there were 24 common peaks in the fingerprints to establish the fingerprint common pattern. The similarity among the 16 batches of samples was calculated,and the results showed it was within the range of 0. 690-0. 993,suggesting the differences among the samples from different factories. Conclusion:The establishment of the fingerprints provides a simple and practical analysis method for more comprehensive regulation of medicinal material sources,effective quality monitoring of the products and the assurance of effective and safe clinical application.
RESUMO
In this paper is presented the Lorenz plot, the qualitative analyses and quantitative parameters of the plot. The long axis vs short axis(LVS) parameter is given. Atrial Fibrillation Electrocardiogram (AF ECG) is compared with sinus ECG by use of Lorenz plot. Then the difference in their plots and the parameter of LVS is pointed out. Lorenz plot finding is useful for the AF disease in automatic diagnoses of ECG signals.