Epidemiologic analysis on severe fever with thrombocytopenia syndrome in Hubei province, 2010 / 中华流行病学杂志

Objective To identify the epidemic characteristics and risk factors of an emerging infectious disease-severe fever with thrombocytopenia syndrome (SFTS) in Hubei province.Methods Active surveillance program on SFTS was set up in monitoring sites-hospitals,at the township level or above,in Suizhou,Huanggang and Wuhan from January to December,2010.Specific surveillance program on SFTS was launched across the province in hospitals above the county level.Cases that matched the definition of surveillance case were identified and reported to Centers for Disease Control and Prevention (CDCs).Cases were interviewed and their blood samples collected and detected using PCR and virus isolation.We also conducted serum antibody surveys among healthy population and livestock and surveillance on vector ticks in those high-epidemic areas.Results 188 cases that matched the definition of surveillance case and 21 deaths were reported in 11 cities,32 countries and 100 towns in 2010,with an incidence rate of 0.33/106.The fatality rate was 11.2％.Data showed that the patients were from hilly areas at the altitude elevated between 28-940 meters.The epidemic period was between April and December with the peak from May to September.The youngest case was an 11-year old,while the eldest was 81 with median age as 56-year old.95.3 ％ of the patients were farmers.All Patients did not have the history of traveling,two weeks before the onset of SFTS.93.6％ of the patients engaged in different kind of work which was associated with agriculture.52.8％ of the patients had been exposed to ticks.22.0％ of the patients had been bitten by ticks.Skin injury was found in 64.2％ of the patients.Samples from 129 cases (68.6％) were collected and detected,with 67.4％ of them (87 cases) showed positive by Real time-PCR for SFTS virus.An elevation in antibody titer by a factor of four or evidence of sero-conversion was observed in 11 patients; SFTS virus was isolated from 2 patients.The total antibody positive rates were 3.8％,55.0％ (6/11 ),36.7％ (2/3) and 80.0％ (4/5) respectively in healthy population,dogs,sheep and cows.Ticks from grass,cattle and sheep were detected positive by Real time-PCR.Conclusion Most cases of SFTS in Hubei were infected by SFTS virus,and cases of livestock were infected by SFTS virus.Ticks might serve as an important vector.Skin injury,exposure to tick bites seemed to be the risk factors.

Generation of trans-arachidonic acid under nitrative stress is associated with upregulation of thromponsdin-1 in diabetic rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Trans-arachidonic acids (TAAs), newly discovered markers of nitrative stress and the major products of nitrogen dioxide (NO2(·))-mediated isomerization of arachidonic acid (AA), represent a new mechanism of NO2(·)-induced toxicity. It has been reported that TAAs were generated in oxygen-induced microvascular degeneration model and TAAs were also generated in a diabetic retinopathy (DR) model. In this study, we examined high glucose-induced nitrative stress damage and TAAs levels and explored the possible mechanisms for DR caused by reactive nitrogen species.</p><p><b>METHODS</b>Diabetic rats were induced by intraperitoneal injection of streptozotocin (STZ) at 60 mg/kg. Bovine retinal capillary endothelial cells (BRECs) were selectively cultured and incubated with normal or high glucose. The serum TAAs and AA in diabetic rats were measured by the gas chromatography and mass spectrometry (GC/MS) method. The ratio of peak area of TAAs to AA with selected ion of 79 was estimated by a group t-test. Thrombospondin-1 (TSP-1) in the rat retinas and BRECs extracts were examined by Western blotting. The phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) protein was examined by Western blotting in BRECs incubated with high glucose.</p><p><b>RESULTS</b>The TAAs to AA ratio (TAAs/AA) was significantly increased in the serum at 8, 12 and 16 weeks after STZ injection (P < 0.05), with no noticeable change found at 2 or 4 weeks (P > 0.05). Expression of TSP-1 in the retina of diabetic rats was progressively elevated according to the duration of diabetes. TSP-1 expression was increased in BRECs incubated with high glucose at 48 hours. Moreover, high glucose also increased ERK1/2 expression, which peaked at 30 minutes and then decreased in the following 48 hours.</p><p><b>CONCLUSION</b>An elevation of TAAs/AA is associated with high glucose-induced nitrative stress, which probably involves upregulation of TSP-1 through activating ERK1/2.</p>

Studies on Apoptosis of Host Cells Induced by Foot-and-Mouth Disease Virus / 中国病毒学

Apoptosis of PK-15 cells induced by Foot-and-Mouth Disease Virus (FMDV) in vitro was reported in this paper. Typical cell apoptosis was detected by use of Hoechst 33258 fluorescence probe, agarose gel electrophoresis and in situ end-labeling (TUNEL). After PK-15 cells were infected by titration of 4.8 lg TCID50/mL FMDV for 32 h, apoptosis characteristics of nuclear condensation, fragmentation, accompanied by apoptotic bodies formation (Hoechst 33258 staining), 180-200 integer-fold sized pieces DNA Ladders (agarose gel electrophoresis) and strong green fluorescence dots (TUNEL) were all exhibited, and cell apoptosis was approximately 20%. In addition, the quantitative analysis of apoptosis in PK-15 cells induced by FMDV showed that apoptosis was correlated with infection of virus, and it was also time-dependent. Results indicate that FMDV can induce apoptosis of host cells and apoptosis plays an important role in the cytopathogencity effect of FMDV.