Genotypes and serotypes of avian infectious bronchitis viruses isolated during 2009-2011 in Guangxi, China / 病毒学报

In order to investigate the prevalence and track genetic and antigenic evolutions of infectious bronchitis virus (IBV) and their prevalence in Guangxi, China since 1985, gene amplification and sequencing and virus neutralization (VN) test on chicken embryo tracheal organ cultures were used in genotyping and serotyping of 28 IBV isolates during 2009-2011 in Guangxi. The results of N gene sequencing and comparison showed that the 28 isolates and reference strains were classified into three groups, and most isolates belonged to group Ill, while the isolates in 1985-2008 belonged to groups IV and II. The data of VN test indicated that the 28 isolates belonged to 6 serotypes; among them, 71. 4% belonged to serotypes 1, 2, and 3, and 11 (39.3%) shared the same serotype with the current vaccine strains. Given the data of our previous study, it is found that prevalent serotypes and their proportions varied in different areas of Guangxi and during different periods. These data lay a good foundation for developing an oil-emulsified inactivated polyvalent vaccine containing local dominant serotypes for the effective prevention and control of infectious bronchitis.

Evaluation of antigenic relationship of Guangxi isolates of infectious bronchitis virus / 病毒学报

Monovalent antisera of 3 vaccine strains and 7 representative field isolates were prepared based on the comparison of genetic diversity of the hypervariable region I of S1 gene (HVR I from 3 infectious bronchitis (IB) vaccine strains (H120, Ma5 and 4/91) ,one reference strain M41 and 26 IB field isolates. These 30 strains were classified in 7 different genotypes, respectively. Virus-neutralizing test on tracheal organ cultures (TOC) with chicken embryo were used to evaluate relatedness values of the antigenicity based on the antibody titer, to analyze the antigenic relationships between the isolates and vaccine strains, as well as to determine the serotypes of 26 IB viruses isolated from the field in Guangxi between 1985 and 2008. The results showed 30 strains were classified into 7 distinct serotypes and there were two predominant serotypes within the 26 isolates, serotypes 1 (totally 13 isolates) and serotype 2 (totally 5 isolates), respectively. In addition, there were some differences observed between the results of serotyping and the genotyping (including the S1, N, M and 3'UTR). The results of the study demonstrated that there were different predominant serotypes and multiple serotypes of IBV circulated in Guangxi in recent years, antigenic variation existed between Guangxi field isolates and vaccine strains.

Quality evaluation of 3 sperm counting chambers by computer-assisted sperm analysis system / 中华男科学杂志

<p><b>OBJECTIVE</b>To compare 3 common sperm counting chambers by the computer-assisted sperm analysis (CASA) system and evaluate their precision in analyzing sperm density and motility.</p><p><b>METHODS</b>We used latex bead solution at (20 +/- 5) x 10(6)/ml as analogue semen samples and analyzed the samples with Makler, Leja and Microcell counting chambers, 30 times with each chamber. And the average (x +/- s) and the coefficient of variation of sperm density were calculated by the CASA system. Meanwhile 54 semen samples collected from the outpatients analyzed with the 3 sperm counting chambers by the CASA system for the rates of forward movement and motility of the sperm.</p><p><b>RESULTS</b>The averages of sperm density obtained with Makler, Leja and Microcell chambers were (25.90 +/- 3.97) x 10(6)/ml, (18.74 +/- 1.62) x 10(6)/ml and (20.35 +/- 2.55) x 10(6)/ml, the coefficients of variation were 15.31%, 8.64% and 12.54%, the rates of sperm forward movement were (46.54 +/- 17.09)%, (30.65 +/- 14.88)% and (30.49 +/- 13.21)%, and the rates of sperm motility were (59.75 +/- 16.12)%, (46.76 +/- 14.11)%, (43.11 +/- 14.02)% respectively. There were significant differences in average sperm density among the 3 groups (P < 0.05). The rates of sperm forward movement and motility obtained with the Makler chamber were significantly higher than those achieved with the Leja chamber and Microcell chamber (P < 0.05), but there were no significant differences between the latter two (P > 0.05).</p><p><b>CONCLUSION</b>The rates of sperm density obtained with the 3 sperm counting chambers differed significantly. In the analysis of sperm motility, a higher rate can be achieved with the coverslip-pressed chamber than the capillary-drawn chamber.</p>

Genetic variation of S1 gene hypervariable region I of infectious bronchitis viruses isolated in different periods in Guangxi / 病毒学报

The S1 gene hypervariable region I (HVR I) of 22 infectious bronchitis virus (IBV) strains isolated in Guangxi during the period of 1985-2007 were sequenced and compared to that of the other IBV reference strains and the pigeon coronavirus isolates. A phylogenetic tree based on nucleotide sequences of HVR I of all the IBV showed that they were classified into 5 distinct Clusters. 16 out of 22 IBV isolates were grouped into Cluster I, and had higher homology with pigeon coronavirus isolates but lower homology with the Massachusetts (Mass) type vaccine strains. There were 4 and 3 amino-acid residues inserted at the sites of 33-34 and 34-35 respectively within HVR I in 15 isolates, except in isolate GX-NN6 there had 4 amino-acid residues inserted at the both sites; isolates GX-YL1 and GX-NN2 had close relationship with Mass type vaccine strains, and they shared Cluster II; isolates GX-G and GX-XD of Cluster III had close relationship with the Japanese strain JP Miyazaki 89 which was isolated at the same period; isolates GX-YL6 and GX-NN7 of Cluster V had close relationship with the European strain 4/91. The results showed that there were high phylogenetic diversity among the IBVs prevailed in the field in Guangxi resulting from the commonly occurred mutation or insertion within the S1 gene HVR I of the viruses, and majority of the isolates had lower homology with the commonly used Mass type vaccine strains. There was much higher homology among viruses isolated in the same period of time, but without distinct difference in geographical origins.

Big Y chromosome not significantly influences outcomes of in vitro fertilization and embryo transfer / 中华男科学杂志

<p><b>OBJECTIVE</b>To evaluate the influence of big Y chromosome on the outcomes of in vitro fertilization and embryo transfer.</p><p><b>METHODS</b>Data of 127 cycles of IVF/ICSI-ET, performed in our Reproductive Medicine Center from March 2001 to June 2003 were analyzed. The patients were divided into two groups according to the length of chromosome: Group A, 56 cycles with big Y chromosome</p><p><b>RESULTS</b>No significant difference was observed in the quality of embryos and in the and Group B, 71 cycles with normal karyotype. rates of fertilization, cleavage, clinical pregnancy, implantation, miscarriage, ectopic pregnancy, dead infant delivery, malformation,</p><p><b>CONCLUSION</b>Big Y chromosome has no significant influence on the baby boy delivery and baby girl delivery between the two groups. development of embryos and the outcome of pregnancy.</p>