Chest Pain ; Humans ; Microcirculation

Objective:To investigate the characteristics of early myocardial mechanics changes in diabetic cardiomyopathy (DCM).Method:Sixty healthy 4-week-old male C57BL/6J mice were randomly divided into the T2DM group ( n=30) and the control group ( n=30). The T2DM group was fed with high-fat diet for 4 weeks, and accepted injection of a single high-dose of streptozotocin (STZ) intraperitoneally. Finally, the model was established successfully in 23 mice. The control group was fed with a normal diet and treated with citrate buffer liquid at an equal dose as T2DM group. Then, nine mice were randomly selected from each of the two groups every 4 weeks until the end of the 24th week. Six of the nine mice were randomly selected to perform 7.0 T MR scanning after measuring blood glucose and body weight. Cine images were acquired through cardiovascular MR feature tracking (CMR-FT). The obtained parameters included the left ventricle global peak circumferential strain (LV-GPCS), left ventricle global peak radial strain(GPRS) and the ejection fraction (EF), etc. The rest three mice were sacrificed for observation of the changes of interstitial fibers and micro-vessels in myocardial tissue with Sirius red staining. One-way analysis of variance (ANOVA) and t test were used for comparison. Results:There were significant differences in blood glucose levels between the two groups during the observation period ( P<0.05). In the 4 th-24 th week, the value of GPCS in T2DM group showed a downward trend, and the difference was statistically significant ( F = 8.23, P<0.001). Compared with the control group, the value of GPCS in T2DM group was statistically significant at the 20 th and 24 th week (the 20 th week: -11.4%±2.1% in the T2DM group vs. -14.3%±1.9% in the control group, t=2.54, P=0.029;the 24 th week: -12.3%±1.7% in the T2DM group vs. -14.6%±1.8% in the control group, t=2.35 , P=0.040), while the EF value was different at the 24 th week (51%±5% in the T2DM group vs. 62%±6% in the control group, t=3.38, P=0.007). There was no significant difference in the GPRS of the T2DM mice group over time or compared with the controls ( P>0.05). Moreover, the pathological results showed that the myocardial interstitial fibers in the T2DM group had remarkably increased since the 12 th week. Conclusions:The alterations in myocardial interstitial fibers and myocardial contractility appeared early in T2DM mice. Especially, the left ventricle global peak circumferential strain value is superior to the EF value in reflecting the early changes in DCM.

Objective To establish a quantitative analysis of multi-compounds by single-marker(QAMS)method for the simultaneous determination of four compounds in formula granules of Pteris multifida and optimize the extraction process of total flavonoids.Methods The relative correction factors(RCFs)of lonicerin,luteolin and apigenin in the formula granules of Pteris multifida were calculated by using the UPLC method with rhoifolin as the internal reference,and their durability was investigated.The external standard method(ESM)was used to determine the content of four compounds in the formula granules of Pteris multifida,and the difference between the calculated values and the measured values was compared.The effects of ultrasonic time,ethanol volume fraction,solid-liquid ratio and ultrasonic power on the extraction rate of total flavonoids were studied by single factor experiment.On this basis,Box-Behnken test with three factors and three levels was conducted to optimize the extraction process of total flavonoids,and the verification experiment was conducted.Results The content of rhoifolin in the formula granules was 0.035%-0.056%,and the content of lonicerin,luteolin and apigenin by QAMS method was 0.085%-0.167%,0.014%-0.028%and 0.004%-0.008%,respectively,which had no significant difference with the external standard method.The optimal extraction conditions of total flavonoids were 80%ethanol water,solid-liquid ratio 1:20,40 minutes extraction,the average extraction rate was 24.46 mg·g-1.Conclusion The established QAMS method was accurate and feasible,and the optimized extraction process of total flavonoids based on Box-Behnken response surface method was simple and feasible,which could lay a foundation for the quality evaluation of the Pteris multifida formula granules.

OBJECTIVEIn March 2012, an H7N7 subtype avian influenza virus (AIV) named A/wild goose/Dongting/PC0360/2012 (H7N7) (DT/PC0360) was recovered from a wild goose in East Dongting Lake. We performed whole-genome sequencing of the isolate, and analyzed the phylogenetic and molecular characterization.

METHODSRNA was extracted from environment samples (including fecal samples from wild bird or domestic ducks, and water samples) for detecting the presence of Influenza A Virus targeting Matrix gene, using realtime RT-PCR assay. The positive samples were performed virus isolation with embryonated eggs. The subtype of the isolates were identified by RT-PCR assay with the H1-H16 and N1-N9 primer set. The whole-genome sequencing of isolates were performed. Phylogenetic and molecular characterizations of the eight genes of the isolates were analyzed.

RESULTSOur results suggested that all the eight gene segments of DT/PC0360 belonged to the Eurasian gene pool, and the HA gene were belonged to distinct sublineage with H7N9 AIV which caused outbreaks in Mainland China in 2013. The hemagglutinin cleavage site of HA of DT/PC0360 showed characterization of low pathogenic avian influenza virus.

CONCLUSIONStrengthening the surveillance of AIVs of wild waterfowl and poultry in this region is vital for our knowledge of the ecology and mechanism of transmission to prevent an influenza pandemic.

Amino Acid Sequence ; Animals ; China ; Embryo, Nonmammalian ; virology ; Feces ; virology ; Geese ; virology ; Genome, Viral ; Influenza A Virus, H7N7 Subtype ; genetics ; isolation & purification ; Influenza in Birds ; virology ; Lakes ; virology ; Molecular Sequence Data ; Phylogeny ; Poultry Diseases ; virology ; RNA, Viral ; genetics ; Real-Time Polymerase Chain Reaction ; veterinary