The impact of relative humidity and atmospheric pressure on mortality in Guangzhou, China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>Although 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.</p><p><b>METHODS</b>This 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.</p><p><b>RESULTS</b>We 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.</p><p><b>CONCLUSION</b>Both 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.</p>

Epidemiological and clinical analysis of Mycoplasma pneumoniae infection in children with acute respiratory tract infection / 南方医科大学学报

<p><b>OBJECTIVE</b>To summarize the epidemiology and clinical characteristics of Mycoplasma pneumoniae (MP) infection in children with acute respiratory tract infection (ARI) in Guangzhou.</p><p><b>METHODS</b>MP was detected using an indirect immunofluorescent method in 2084 children with ARI. The relations between MP infection rate and the gender, age, season, site of infection and wheezing diseases were analyzed.</p><p><b>RESULTS</b>A total of 433 children (20.8%) were positive for MP, including 222 boys (19.8%) and 211 girls (21.9%) without significant difference in the infection rate between the genders (P>0.05). In 0- to 3-year-old group, 106 children were positive for MP (15.0%), while in 3- to 5-year-old group and 5- to 14-year-old group, 163 (25.2%) and 164 (22.5%) were positive, respectively, showing a significant difference in the infection rate between the 3 groups (P<0.05). The MP infection rate was 18.0% in January to March, 25.1% in April to June, 17.7% in July to September, and 20.5% in October to December, showing significant differences between the periods (P<0.05). No significant difference was found in the infection rate between children with acute upper respiratory tract infection (URI) and those with lower respiratory tract infection (LRI) (P>0.05). Among the children with LRI, those having wheezing disease had significantly higher MP positivity rate than those without wheezing.</p><p><b>CONCLUSION</b>MP is a common causative agent for ARI in children. MP infection is not related to gender and infection site, but to age and season. Children over 3 years old are vulnerable to MP infection. MP infection can be associated with wheezing in LRI.</p>

Ultrastructural changes of the extraintestinal organs of newborn mice with human rotavirus infection / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the ultrastructural changes of the extraintestinal organs of newborn mice with human retrovirus (RV) infection to probe into the mechanism and clinical diagnose and therapy of extraintestinal RV infection.</p><p><b>METHODS</b>Human RV was inoculated into the abdominal cavity of the newborn mice, and the ultrastructural changes of the heart, lung, livers, and kidneys of the infected and control mice were observed by transmission electron microscope.</p><p><b>RESULTS</b>The mice with intraabdominal RV injection showed pathological changes of the cells in the small intestinal villus, liver, and kidneys. Shortened small intestinal villus, nuclear membrane disorganization, massive vacuolization, mitochondrial swelling and rough endoplasmic reticulum dilation were observed in the cells of the small intestinal. In the liver of the mice, marked mitochondrial swelling and agglutination, cell nucleus pyknosis or collapse, presence of numerous lipid droplets and vacuoles were seen in the liver cells, with lymphocyte and plasmacyte infiltration. Obvious dilatation and shedding of the microvillus were seen in cholangioles. The mitochondria of the proximal convoluted renal tubule showed mild swelling, but the cells in the heart and lung did not display obvious changes.</p><p><b>CONCLUSION</b>The small intestinal villi were highly susceptible to RV infection, and systemic spread of human RV may cause damage of various extraintestinal organs especially the liver, which can also be susceptible to RV.</p>

Factors triggering extraintestinal infection of rotavirus / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of immunodeficiency and intestinal mixed infection on inducing extraintestinal dissemination of rotavirus (RV).</p><p><b>METHODS</b>Immunodeficiency was induced in healthy Kunming mice by introperitoneal injection of cyclophosphamide, and RV was administered either orally or via intraperitoneal injection. In another group, toxigenic E. coli and human RV were given sequentially by intragastric administration to induce mixed infection. Three days later the organs of the mice were taken for pathological examination, and RV was detected by in situ PCR and hybridization. In children with or without viremia of rotavirus, blood tests for levels of tumor necrosis factor alpha (TNF-alpha), interleukin-2 (IL-2) and 7 trace elements (zinc, iron, copper, lead, calcium, manganese, and magnesium) were performed.</p><p><b>RESULTS</b>In immunodeficient mice, pathological changes were found in the small intestinal villus, gastric lamina propria and the cardiac cells of mice taking RV orally, and the mice with intraperitoneal RV injection showed additional liver and kidney pathologies. In mice with mixed infections, pathological changes occurred in the intestines, livers and kidneys. In situ hybridization detected RV in the intestinal villus of immunodeficient mice with oral RV administration, and in the intestinal villus and kidneys of the mice with mixed infections. In situ PCR revealed the presence of RV in the intestinal villus, intestinal gland cells, epithelial cells of the proximal convoluted tubules and collecting tubes in the kidneys of immunodeficient mice taking RV orally, in the intestinal villus, kidneys, livers, hearts and pancreases of those with RV injection, and in the intestines, kidneys, and livers of the mice with mixed infection. Children with rotavirus viremia had TNF-alpha level in comparison with those free of rotavirus viremia, and the majority of the former children showed disorder in trace elements.</p><p><b>CONCLUSION</b>Immunodeficiency, mixed infection and malnutrition can be important factors contributing to or exacerbating RV infection and extraintestinal RV dissemination.</p>

Depressant Effect of siRNA on the Expression and Replication of Hepatitis B Virus in HepG2.2.15 Cell / 实用儿科临床杂志

Objective To explore the siRNA as a new antiviral therapy,evaluate the inhibition effect of siRNA based on vector on the HBV of HepG2.2.15 cell,and observe the side effect and toxicity of siRNA vector on cells and the off-target effect of siRNA.Methods Three pairs of siRNA duplexes targeting HBV C gene were designed as double strands,and the duplex were annealed and ligated into the p-Silencer-Cmv 4.1-hygro vector.The ligation products were used to transform JM109 cells.The clones with shRNA were obtained,and the vectors were purified.After the initial identification of the vector with agarose gel and the size of the inserted sequence got examined by native polyacrylamide gel electrophoresis,furthermore the sequencing was further carried out.The recombinant plasmids were purified with ultrapure Midipreps DNA Purification System.Then HepG2.2.15 cells were transfected with the plasmid mixed with siPort XP-1.The expression of HBsAg and HBeAg were detected by immunofluorescence and Western blot,and the HBV RNA was investigated by RT-PCR.Furthermore the real-time quantitive PCR was carried out to detect the changes of HBV DNA.In order to evaluate the toxicity of the shRNA,MTT was used to examine the growth rate and curve of cells.The ELISA was performed to detect the changes of interferon-? (IFN-?).Results The Western blot showed that the HBsAg and HBeAg protein were suppressed with (81.15?0.69)%,(88.12?0.92)% respectively by vector p-C2 on the third day of post-transfection.It had the similar result indicated by immunofluorescence.And the RT-PCR showed that the specific siRNA targeting HBV C gene could markedly suppress the expression of HBV mRNA and the HBV C gene mRNA was inhibited with 96.9%.The real-time quantitive PCR showed that the specific functional siRNA could markedly suppress HBV DNA copy with two orders of magnitude,while the siRNA vector had no effect on the growth of cell showed by MTT detection.Compared with the non-transfected group and p-NC group,the IFN-? level was almost the same with siRNA p-C1,p-C2,p-C3 groups.Conclusions The siRNA based on the expression vector can suppress the expression and replication of HBV in HepG2.2.15 cell.The inhibition effect was specific and had a certain dependency on siRNA concentration.No toxicity effect was found in the study.And the drug resistance wouldn′t happen because the silence was based on the split of gene.

Experimental Study of Rotavirus Infection in Whole Body of Newborn Mouse / 实用儿科临床杂志

Objective To explore the hurt of susceptibility organs and critical orgens followed by rotavirus (RV) infection of whole body in newborn mouse.Methods RV strain was derived from the stool samples of patients with RV diarrhea and was proved to be long type by methods of ELISA and polyacrylamide gel electrophoresis (PAGE). RV was inoculated by the pathways of taking orally and injected to abdominal cavities,respectively. The pathological changes of the newborn mouse model infected with human natural RV by light microscope and electron microscope. The gene probe was marked by digoxin.The direct prove of RV infection in these organs was got by the detection of in situ PCR. Results Pathological changes were found in the small intestinal villus,lamina propria of the stomach and the heart cells of the mice taken RV orally.The mice with intraabdominal RV injection showed pathological changes of the cells in the small intestinal villus,liver and kidneys observed by electron microscope.Shortened small intestinal villus,nuclear membrane disorganization,massive vacuolization,mitochondrial swelling and rough endoplasmic reticulum dilation were observed in the cells of small intestinal.In the liver of the mice,marked mitochondrial swelling and agglutination,cell nucleus pyknosis or collapse,presence of numerous lipid droplets and vacuoles were found in the li-ver cells,with lymphocyte and plasmacyte infiltration.Obvious dilatation and shedding of the microvillus were found in cholangioles.The mitochondria of the proximal convoluted renal tubule showed mild swelling,but the cells in the heart and lung did not display obvious changes.Conclusion RV can damage lots of extra intestinal organs of the newborn mice if RV diffuses to the whole body of the mice.