[Analysis on prevalence and epidemic risk of animal plague in different ecological plague foci in Inner Mongolia Autonomous Region].

The risk of plague epidemics and relapse of various types of plague foci persists in Inner Mongolia Autonomous Region. For Marmota sibirica plague foci, the animal plague has not been found but antibody has been detected positive. Nowadays, Marmota sibirica has been increasing in population and distribution in China. In bordering countries Mongolia and Russia, the animal plague has been continuously prevalent. For Spermophilus dauricus plague foci, the animal plague has been taken place now and then. Compared to the above foci, the animal plague is most prevalent in Meriones unguiculatus plague foci and frequently spread to humans. Due to higher strain virulence and historical disaster in Marmota sibirica plague foci and Spermophilus dauricus plague foci, plague prevention and control should be strengthened on these foci. In addition to routine surveillance, epidemic dynamics need to be further monitored in these two foci, in order to prevent their relapse and spread to humans.

Assessment of vitamin A requirement of gosling in 0-28 d based on growth performance and bone indexes.

A dose-response experiment assessing 6 total dietary vitamin A (VA) levels (0, 3,000, 6,000, 9,000, 12,000, and 15,000 IU/kg) was conducted to study the effects of different levels of VA on growth performance and bone indexes of 0 to 28 d goslings. A total of 360 healthy 1-day-old goslings with similar body weights were randomly divided into 6 groups with 6 replicates in each group and 10 goslings in each replicate. The experiment duration was 28 d. The experimental results showed that the VA content in the serum and liver of gosling increased with increasing VA amount (P < 0.05). When the diet was supplemented with 9,000 IU/kg VA, the content of vitamin D in serum and the liver was higher than those in other groups (P < 0.05). The 28-day body weight and average daily gain in gosling in the 9,000 IU/kg VA group were higher than those in the 0, 3,000 and 15,000 IU/kg VA groups (P < 0.05). Growth hormone, thyroxine, and parathyroid hormone levels in the 9,000 IU/kg VA group were higher than those in the 0, 3,000, 6,000 and 15,000 IU/kg VA groups (P < 0.05). The insulin level in the 9,000 IU/kg VA group was higher than those in the other groups (P < 0.05). The osteocalcin (BGP) levels in the VA supplementation groups were higher than that in the no VA groups (P < 0.05). The tibia length and phosphorus content in the 9,000 IU/kg VA group were higher than those in the 12,000 IU/kg VA group and 15,000 IU/kg VA group (P < 0.05). The tibia shear hardness values in the 6,000, 9,000 and 12,000 IU/kg VA groups were higher than those in the 0, 3,000 and 15,000 IU/kg VA groups (P < 0.05). The tibia calcium content in the 9,000 IU/kg VA group was higher than those in the 0 and 15,000 IU/kg VA groups (P < 0.05). The tibia crude ash content in the 9,000 IU/kg VA group was higher than that in the 15,000 IU/kg VA group (P < 0.05). In conclusion, the optimum dietary VA supplementation for 0- to 8 day gosling was 9,000 IU/kg.

MiR-129-5p protects against myocardial ischemia-reperfusion injury via targeting HMGB1.

OBJECTIVE: To investigate the protective effect of miR-129-5p on ischemia-reperfusion (I/R) injury via targeting high mobility group box-1 (HMGB1). MATERIALS AND METHODS: Rat models of myocardial I/R and hypoxia/reoxygenation (H/R) cardiomyocytes were established, and the miR-129-5p and HMGB1 expression levels in myocardium of I/R rats and in cardiomyocytes of H/R rats were quantified by RT-PCR. The over-expression of miR-129-5p was performed on I/R rats, and the over-expression of miR-129-5p and down-regulation of HMGB1 were performed on cardiomyocytes of H/R rats. Triphenyltetrazolium chloride (TTC) staining was used to measure myocardial infarct size (IS). TUNEL (TdT-mediated dUTP end nick labeling) staining was employed to observe cardiomyocyte apoptosis in the myocardium of rats, and flow cytometry to observe cardiomyocyte apoptosis of I/R and H/R rats respectively. Dual-Luciferase reporter assay was used to verify the target relation between miR-129-5p and HMGB1. RESULTS: MiR-129-5p was lowly expressed and HMGB1 was highly expressed in myocardial I/R injury rats and cardiomyocytes of H/R rats. Over-expression of miR-129-5p effectively reduced myocardial IS and cardiomyocyte apoptosis in rats with myocardial I/R injury, and significantly down-regulated the pro-apoptotic protein Bax, as well as significantly up-regulated the anti-apoptotic protein Bcl-2. Either over-expression of miR-129-5p or low-expression of HMGB1 in cardiomyocytes of H/R rats also achieved the same effects as described above. Dual-Luciferase reporter assay determined that miR-129-5p was a target for HMGB1. CONCLUSIONS: MiR-129-5p plays a protective role on myocardial I/R injury by regulating HMGB1 expression. Besides, it inhibits cardiomyocyte apoptosis and is expected to become a novel molecular marker or therapeutic target for myocardial I/R injury.

The effect of dietary vitamin A supplementation in maternal and its offspring on the early growth performance, liver vitamin A content, and antioxidant index of goslings.

This study investigated the effect of dietary VA supplementation on maternal and its offspring in terms of the early growth performance, antioxidant index, and tissue VA content of the goslings. Yangzhou geese aged 180 D were selected and randomly distributed into 5 experimental groups with 15 female geese and 3 male geese in each group. The geese were fed a basal diet supplemented with 0, 4,000, 8,000, 12,000, or 16,000 IU/kg VA. Eggs were collected from each group starting at 300 D. After hatching, 96 goslings were selected from each maternal group and randomly distributed into 2 experimental groups with factorial arrangement (6 replicates × 8 geese), including 2 levels of VA supplementations, 0 and 9,000 IU/kg. The results are as follows: (1) Different levels of maternal VA supplementation significantly affected the BW and weight gain of 7-day-old offspring (P < 0.05). The weight gain of offspring administered 9,000 IU/kg VA was significantly higher than that of offspring administered the basal diet (P < 0.05). (2) Maternal VA levels significantly affected the T3, T4, and insulin levels of the offspring (P < 0.05). (3) The GSH-PX, SOD, T-AOC, CAT, and tissue VA content of the offspring were significantly higher and MDA was significantly lower in the 9,000 IU/kg VA group than in the no VA group (P < 0.05). (4) Maternal VA levels had a significant effect on offspring GSH, GSH-PX, SOD, MDA, T-AOC, and CAT (P < 0.05). Maternal and offspring VA supplementation interact with the weight gain, tissue VA content, GSH, GSH-PX, SOD, MDA, and CAT of goslings (P < 0.05). Maternal supplementation with 12,000 IU/kg VA and offspring supplementation with 9,000 IU/kg VA was conducive to gosling growth.

[Etiological study of diarrhea in children under 5 years old in Dongcheng district of Beijing].

Objective: To analyze the etiological characteristics of infectious diarrhea among people under 5 years old in Dongcheng District, Beijing. Methods: The age, time of infection, clinical symptoms and laboratory test results of the cases who didn't used antibiotics within 3 days in the second maternal and child health care hospital were collected from 2012 to 2015, through the information management system of infectious disease monitoring technology platform. To compare the detection rate of virus and bacteria in children with different sex, time and age,and the difference of clinical characteristics between virus detection group and bacteria detection group by chi square test. Results: 1 977 cases of infectious diarrhea were collected, the median of the month age (P(25), P(75)) was 14.19 (8.31, 23.15) months. The virus detection rate was 34.3% (679 cases); the bacterial detection rate was 14.6% (288 cases). The difference of virus detection rate in children with different months was statistically significant (χ(2)=72.38, P<0.001), the virus detection rate of 24-60 months (40.9% (188/460)) was the hightest, and the detection rate of 0-5 months (15.3% (48/314)) was the lowest. The difference of bacteria detection rate was also statistically significant (χ(2)=32.67, P<0.001), and the detection rate of 12-17 months (19.0% (81/426)) was the highest, the detection rate of 0-5 months (6.7% (21/314)) was the lowest. The proportion of vomit and water sample in the virus detection group was 22.2% (136 cases) and 73.3% (449 cases), respectively, which were higher than those in bacteria detection group (8.1% (18 cases) and 57.2% (127 cases)), the difference was statistically significant (χ(2) values were 125.92 and 19.60; P values were both<0.001); the proportion of mucus stool and fever was 0.8% (5 cases) and 14.0% (86 cases), respectively, which were lower than those in bacterial detection group (4.1% (9 cases) and 18.5% (41 cases)), and the difference was statistically significant (χ(2) values were 8.50 and 23.01; P values were 0.004 and <0.001). Conclusion: The virus detection rate of infantile infective diarrhea is higher than that of bacteria in Dongcheng district of Beijing, and the clinical characteristics are significantly different.

[The effect of AmpD on the expression of AmpC ß-lactamase and the regulation mechanisms of ß-N-acetylglucosaminidase in Yersinia enterocolitica].

Objective: In this study, we analyze the regulation mechanisms of the expression of ampD in AmpC ß-lactamase and the regulation mechanism of ß-N-acetylglucosaminidase (NagZ) in Yersinia enterocolitica. Methods: We construct the mutation strains of Yersinia enterocolitica AmpD (AmpD1-3) gene (ampD1-3), Low-Molecular-Mass Penicillin-Binding Proteins (LMM PBPs) gene (pbp4, pbp5a, pbp5b, pbp7), NagZ gene (nagZ), and ampR gene by deleting and complementing genes, and induce them by cefoxitin. We determined the activity of AmpC ß-lactamase activity (U) of mutant strains (basal level and induce level) by using cephalothiophene hydrolysis method, the promoter activity of AmpC ß-lactamase ((relative light unit (RLU)) was detected by the luxCDABEreporter system, and the activity of ß-N-acetylglucosaminidase (nmol/L) was determined by by using 4-nitrophenyl N-acetyl-ß-D-glucosaminide as the chromogenic substrate. Results: AmpD1 (Basal level: (3.29±1.58) U; Induced level: (4.08±1.75) U) was the most potent one. The YEΔ5b, YEΔ4Δ5b, YEΔ5aΔ5b and YEΔ5bΔ7 of ampC promoter activity increase significantly, whichYEΔ4Δ5b is the highest one (Basal level: (106 903.16±61 910.61) RLU; Induced level: (205 427.45±45 352.17) RLU). The YEΔ4Δ5bΔ7 of ampC promoter activity is the highest among triple mutant strain (Basal level: (304 108.04±99 274.53) RLU; Induced level: (531 440.21±68 891.02) RLU). Quadruple deletion strain YEΔ4Δ5aΔ5bΔ7 have the highest ampC promoter activity (Basal level: (1 013 810.99±260 955.96) RLU; Induced level: (1 230 214.59±205 526.79) RLU). After the deletion of nagZ gene, there is no significant change in ß-lactamase activity of YEΔD1D2D3ΔZ, while ß-lactamase activity of YEΔ4Δ5aΔ5bΔ7ΔZ shows a significant decrease (Basal level: (0.30±0.20) U; Induced level: (0.29±0.21) U), which basically drops to the wild strain level. Conclusion: This is the first report of ampC multi-step upregulation mechanism driven by three AmpD homologues in Yersinia enterocolitica. The AmpC regulation mode with the function of single PBP4, PBP5a or PBP7 is relatively low, which work in coordination with PBP5b. Yersinia enterocolitica have both NagZ-depend and NagZ-independent mechanisms for ß-lactamase expression.

Fractionation and characterization of sludge bacterial extracellular polymers by FT-IR, 13C-NMR, 1H-NMR.

Sludge bacterial extracellular (BEP) polymers exhibit a strong affinity with metals in addition to their role in the bioflocculation of activated sludge. It is of utmost importance in elucidating the chemical characterization of sludge BEP prior to a better understanding of its environmental behavior. Sludge BEP extracted from activated sludge was characterized by FT-IR, 1H-NMR, and 13C-NMR and fractionated into 6 fractions (hydrophilic acid, base, and neutral; and hydrophobic acid, base, and neutral). The results indicated that sludge BEP contained more polysaccharides but fewer amino acids or proteinaceous materials compared to dissolved organic matter (DOM) derived from sludge. No aromatic substance was found in sludge BEP as indicated by NMR. Sludge BEP was dominated by hydrophilic fractions, accounting for 65% of total DOC of sludge BEP and hydrophilic neutral constituted about 58% of the hydrophilic fraction. The chemical fraction and characterization indicated that sludge BEP might exhibit a higher capability in enhancing the transport of the associated contaminants through porous media than that of sludge DOM.