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Semen is a measure of the reproductive efficiency of roosters, which affects the economic benefits of white‐feathered broilers. Over the years, research in this field has mainly focused on hens, while there have been fewer studies on the reproductive traits of roosters. To identify the genes related to the semen traits of roosters, we used a chicken 55 K SNP chip to genetically type the white‐feathered population (220) and performed imputation with resequencing data from 97 roosters. In total, 1 048 576 SNPs were obtained and used for genome‐wide association analysis of semen volume, from which 197 genome‐wide significant markers were identified, all within the interval of 13.82–16.12 Mb on chromosome 7. By combining our results with the biological functions of genes in the interval, four candidate genes were identified that potentially relate to semen volume: FAPP1, OSBPL6, SESTD1 and SSFA2. Our findings may provide a basis for further research on the genetic mechanism and marker‐assisted selection of semen volume in white‐feathered broilers. [ABSTRACT FROM AUTHOR]

We describe the epidemiology of hepatitis B virus ( HBV) infection among women of reproductive age residing in areas of China that are highly endemic for chronic HBV, and provide evidence useful for decision-makers to guide strategies for preventing mother-to-child transmission of HBV, and assess the impact of perinatal transmission PMTCT by projecting HBsAg prevalence trends without interventions. We conducted a cross-sectional HBV serological survey of women, 15-49 years of age, residing in Fujian, Guangdong, Guangxi and Hainan provinces. Demographic and other subject-level data were collected in face-to-face interviews, after which we obtain blood specimens. Specimens were tested for HBV sero-markers by ELISA (Beijing Wantai Biological Pharmacy), and HBV DNA was tested with PCR (Hunan Sansure Biotech). Weighted HBsAg and HBV (either HBsAg+ or anti- HBc+ indicating either present or past infection) prevalences were 11.82% and 57.16%, respectively. Among the HBsAg-positive women, 27% were also HBeAg positive. The proportion of individuals with HBV DNA loads >105IU/mL declined with increasing age. Among HBsAg-negative women, 0.9% had occult HBV infection. The prevalence of chronic HBV infection among reproductive women in these highly endemic provinces is high, posing a threat to maternal health and risk of mother-to-child transmission. Prevention of mother-to-child transmission remains critically important. [ABSTRACT FROM AUTHOR]

The corrosion behavior of a 304 oxide dispersion strengthened (ODS) austenitic stainless steel after being exposed to supercritical water (SCW) with dissolved oxygen of 300 ppb at 600 °C/25 MPa was studied. By the means of a least-square fit, the weight gain (Δ w) of the samples as a function of exposure time ( t) could be described by the equation Δ w = 8.011 × t0.459. An approximately parabolic time law in this specified SCW environment can be assumed. A triple protective oxide layer formed on the surface of the metal with the exposure time up to 1000 h. Furthermore, the result of slow-strain rate tensile (SSRT) test indicated that the 304-ODS austenitic stainless steel was not susceptible to stress corrosion cracking (SCC) in SCW at 600 °C/25 MPa. [ABSTRACT FROM AUTHOR]

Myeloid-derived suppressor cells ( MDSCs), a heterogeneous population including myeloid progenitor and immature myeloid cells, are known to inhibit T cell responses. The issue of whether tumour-derived MDSCs regulate the immune response in an asthma environment is currently unclear. Here, we have reported that tumour-derived MDSCs shift the balance back to normal in a Th2-dominant asthmatic environment. In an ovalbumin ( OVA)-induced mouse asthma model, injected tumour-derived MDSCs were recruited to the lungs of asthmatic mice by CC chemokine ligand 2 ( CCL2). MDSCs transferred into asthmatic mice via i.v. injection suppressed the infiltration of inflammatory cells into the lung, the Th2 cytokine, IL-4, concentration in bronchial lavage fluid and the serum level of OVA-specific Ig E. Increased TGF- β1 production in the lung was detected after transfer of MDSCs. The inhibitory effects of MDSCs were reversed upon treatment with an anti- TGF- β1 antibody, suggesting dependence of these activities on TGF- β1. Our findings imply that tumour-derived MDSCs inhibit the Th2 cell-mediated response against allergen in a TGF- β1-dependent manner. Based on the collective results, we propose that asthma may be effectively targeted using a novel MDSC-based cell therapy approach. [ABSTRACT FROM AUTHOR]

Background: Although the prevalence of allergic asthma increased quickly in the past decade, the diagnostic criteria have not been well established. The aim of the present study was to explore whether stem cell factor (SCF), B cell-activating factor (BAFF), and cytokines interleukin (IL)-17 and IL-31 are usable parameters for the diagnosis of allergic asthmatics. Methods: Blood samples were collected from patients with allergic asthma, control patients, and healthy control subjects. The serum concentrations of SCF, BAFF, IL-17, and IL-31 were measured by enzyme-linked immunosorbent assay. The corresponding mRNA levels in peripheral blood mononuclear cells (PBMCs) were determined by real-time reverse-transcription polymerase chain reaction. Results: A good correlation existed between protein levels of SCF and IL-31 and their mRNA levels (SCF: r = 0.6162; IL-31: r = 0.5463). The serum concentrations of SCF and IL-31 in allergic asthmatic patients, but not control patients, were significantly higher than those in normal control subjects (SCF: median 1.83 vs 0.85 ng/ml, P < 0.01; IL-31: 50.15 vs 10.01 pg/ml, P < 0.001). Consistently, the levels of SCF and IL-31 mRNAs in allergic asthmatic patients’ PBMCs were also significantly higher than those in normal control subjects ( P = 0.002 and P < 0.001, respectively). Conclusions: These findings suggest that allergic asthma is characterized by an elevation of cytokines SCF and IL-31 and the measurement of their expression at either protein level in serum or mRNA level in PBMCs will be a valuable parameter for the diagnosis of allergic asthma. [ABSTRACT FROM AUTHOR]

In 2005, rose plants ( Rosa rugosa cv. ‘Plena’) exhibiting typical phytoplasma disease symptoms of stunting, yellowing, witches’-broom and dieback were observed in Pingyin, Shandong Province, China. The disease, rose witches’-broom (RoWB), is progressively destructive and can be graft-transmitted. Polymerase chain reaction (PCR), sequencing of PCR products and electron microscopy were used to investigate the possible association of phytoplasma with RoWB. All results indicated that presence of phytoplasma in the symptomatic rose plants. Sequence alignment of 16S rRNA gene, tuf gene and rp gene confirmed that the phytoplasma associated with RoWB is the causal agent of Paulownia witches’-broom disease, which might be transmitted from the paulownia tree that is several meters away. To our knowledge, this is the first report of the molecular characterization of phytoplasma infecting rose in China. [ABSTRACT FROM AUTHOR]

The solanum fruit fly,Bactrocera latifrons(Hendel), is a major agricultural pest in Asia and Hawaii, and it is important to prevent its widespread invasion in plant quarantine. In this study we introduced a real-time polymerase chain reaction (PCR) essay, using SYBR Green I dye, to rapidly identifyB. latifronson an ABI PRISM 7700 sequence detection system. A latifron-specific PCR primer set was obtained based on mtDNA COI gene ofB. latifrons. NineBactrocerafruit flies,B. latifrons,Bactrocera dorsalis,Bactrocera papayae,Bactrocera carambolae,Bactrocera philippinensis,Bactrocera occipitalis,Bactrocera correcta,Bactrocera cucurbitaeandBactrocera tau, were used to determine the specificity of primers lati1 and lati2. A series of genomic DNA dilutions ofB. latifrons(0.01, 0.1, 1, 10, 20, 40 and 100 ng) were used to assess the sensitivity of the SYBR Green PCR. Template DNA concentration was one of the sources of variability in cycle threshold values (CT) and the optimum DNA concentration was between 1 and 20 ng. Genomic DNA isolated from larvae, pupae and adult specimens ofB. latifronswere used to assess the specificity of the SYBR Green PCR. Melting curve analysis and agarose gel electrophoresis was employed to check the specificity of PCR products. Similar amplification plots were obtained using DNA from the three different stages ofB. latifronswith primer set lati1/lati2. The melting temperature (Tm) of PCR products was 77.5 ± 0.1°C, and the length of the amplified fragment 366 bp. Given the specificity and sensitivity of the assay, combined with high speed, low cost and the possibility of automating, SYBR Green PCR can be used as a rapid and specific technique for pest species identification in plant quarantine. [ABSTRACT FROM AUTHOR]