The phylogenetic analysis of avipoxvirus in New Zealand

Avipoxvirus is known to be endemic in New Zealand and it is a cause of ongoing mortalities in the endangered black robin and shore plover populations. There is no information on the strains of avipoxvirus occurring in New Zealand and their likely origin or pathogenicity. This study was designed to identify the phylogenetic relationships of pathogenic avipoxvirus strains infecting introduced, native, and endemic bird species in New Zealand. Avipoxvirus 4b core protein gene was detected in tissue samples from 25/48 birds (52.1%) from 15 different species in New Zealand. Bootstrap analysis of avipoxvirus 4b core protein gene revealed that the New Zealand avipoxvirus isolates comprised of three different subclades. The majority of New Zealand avipoxvirus isolates (74%) belonged to A1 subclade which shared 100% genetic similarity with the fowlpox HPB strain. An isolate from a wood-pigeon (kereru) belonged to subclade A3, displaying 100% sequence homology to albatrosspox virus. An additional group, isolated from two shore plovers and one South Island saddleback, grouped within subclade B1 and presented 99% sequence homology to European PM33/2007 and Hawaiian HAAM 22.10H8 isolates. The results suggest that a variety of New Zealand bird species are susceptible to avipoxvirus infection, that there are more than two distinctive avipoxvirus subclades in New Zealand, and that the most prevalent A1 strain may have been introduced to New Zealand through introduced avian hosts such as passerines or poultry.     

骆驼刺下胚轴组织培养和植株再生研究

实验分别以ＭＳ、１／ＳＭＳ为基本培养基，采用不同浓度组合的ＫＴ、ＮＡＡ和蔗糖进行骆刺下胚轴组织培养再生植株过程的研究。结果表明，分化培养基ＭＳ＋４．０ｍｇ／ＬＫＴ＋２０ｇ／Ｌ糖对诱导下胚轴分化出丛生芽效果最好。     

Evaluation of immunochromatographic assay for serodiagnosis of Brucella canis

Canine brucellosis is a contagious disease with venereal and oral modes of transmission that produces late abortion in females, epididymides and prostates in males. Diagnosis is difficult because of unstable serum antibody titers that vary from individual to individual as well as between different methods used for their detection. The objective of this work was to evaluate the clinical utility of the immunochromatographic assay (ICA) for serodiagnosis of dogs suspected of having brucellosis, and results were compared with those obtained for hemoculture (HC) and the rapid screening agglutination with 2-mercaptoethanol (2-ME RSAT). The all experimentally infected dogs were positive in ICA, HC and 2-ME RSAT from 5 weeks, 7 weeks, and 3 weeks after infection, respectively. Also, among dogs selected from 10 different breed kennels occurred brucellosis, 24.8%, 39.5% and 39.1% of dogs tested were detected as positive with HC, 2-ME RSAT and ICA, respectively. The kappa value between 2-ME RSAT and ICA was 0.89. The results of this study showed that sensitivity and specificity of the ICA are comparable with those obtained using conventional serological and bacteriological test for brucellosis. In conclusion, the ICA kit provides a handy and accurate tool for the rapid serodiagnosis of canine brucellosis.     

Effects of Co‐culture of Cumulus Oocyte Complexes with Denuded Oocytes During In Vitro Maturation on the Developmental Competence of Cloned Bovine Embryos

This study evaluated the effects of co‐culture of immature cumulus oocyte complexes (COCs) with denuded immature oocytes (DO) during in vitro maturation on the developmental competence and quality of cloned bovine embryos. We demonstrated that developmental competence, judged by the blastocyst formation rate, was significantly higher in the co‐cultured somatic cell nuclear transfer (SCNT+DO, 37.1 ± 1.1%) group than that in the non‐co‐cultured somatic cell nuclear transfer (SCNT‐DO, 25.1 ± 0.9%) group and was very similar to that in the control IVF (IVF, 38.8 ± 2.8%) group. Moreover, the total cell number per blastocyst in the SCNT+DO group (101.7 ± 6.2) was higher than that in the SCNT‐DO group (81.7 ± 4.3), while still less than that in the IVF group (133.3 ± 6.0). Furthermore, our data showed that mRNA levels of the methylation‐related genes DNMT1 and DNMT3a in the SCNT+DO group were similar to that in the IVF group, while they were significantly higher in the SCNT‐DO group. Similarly, while the mRNA levels of the deacetylation‐related genes HDAC2 and HDAC3 were significantly higher in the SCNT‐DO group, they were comparable between the IVF and SCNT+DO groups. However, the mRNA levels of HDAC1 and DNMT3B were significantly higher in the SCNT+DO group than in the other groups. In conclusion, the present study demonstrated that co‐culture of COCs with DO improves the in vitro developmental competence and quality of cloned embryos, as evidenced by increased total cell number.     

Intrapancreatic ectopic splenic tissue found in a cloned miniature pig

Somatic cell nuclear transfer (SCNT) is a cost-effective technique for producing transgenic pigs. However, abnormalities in the cloned pigs might prevent use these animals for clinical applications or disease modeling. In the present study, we generated several cloned pigs. One of the pigs was found to have intrapancreatic ectopic splenic tissue during histopathology analysis although this animal was grossly normal and genetically identical to the other cloned pigs. Ectopic splenic tissue in the pancreas is very rare, especially in animals. To the best of our knowledge, this is the first such report for cloned pigs.     

国槐SSR-PCR反应体系的建立与优化

利用单因素试验结合L₁₆（4⁵）正交试验设计对国槐SSR-PCR反应体系中的5个主要影响因素(Mg²⁺、引物、dNTPs、ExTaq酶、模板DNA用量)进行优化,确定最佳反应体系为（10μL）:25 mmol/L Mg²⁺1.0μL,2.5 mmol/L dNTPs 0.2μL,10μmol/L上下游引物共0.5μL,5 U/μL ExTaq酶0.05μL,30 ng/μL模板DNA 1.0μL,10×PCR Buffer 1.0μL,ddH₂O 6.25μL。随机挑选4对SSR引物和8个国槐种质对试验确定的最佳反应体系进行验证,均能获得清晰、稳定的条带。该优化反应体系的建立为利用SSR标记对国槐种质资源进行深入研究和利用奠定了基础。     

桃新品种——“北农早艳”、“北农二号”

培育过程:我们根据1956—57年北京郊区桃品种的调查情况,自1958年开始桃的育种。经过1958、60—63年的杂交工作,定植了一批杂种实生苗。先后从中初选出十多个优良单系。这些单系有的在北京郊区试种,有的引入上海、江苏、山西、四川等地试种。十多年来,其中二个单系已有小片生产果园或已扩大试种。1979年又经过较全面的鉴定,分别定名为北农早艳(原名6—25)与北农二号(原代号60—23—2)。     

Control of synaptic strength by glial TNFalpha

Activity-dependent modulation of synaptic efficacy in the brain contributes to neural circuit development and experience-dependent plasticity. Although glia are affected by activity and ensheathe synapses, their influence on synaptic strength has largely been ignored. Here, we show that a protein produced by glia, tumor necrosis factor alpha (TNFalpha), enhances synaptic efficacy by increasing surface expression of AMPA receptors. Preventing the actions of endogenous TNFalpha has the opposite effects. Thus, the continual presence of TNFalpha is required for preservation of synaptic strength at excitatory synapses. Through its effects on AMPA receptor trafficking, TNFalpha may play roles in synaptic plasticity and modulating responses to neural injury.     

Preparation of high molecular weight atactic poly(vinyl alcohol) by photo-induced bulk polymerization of vinyl acetate

Vinyl acetate was polymerized in ultraviolet-ray initiated bulk system at low temperatures using 2,2′-azobis(2,4-dimethylvaleronitrile) (ADMVN) or 2,2′-azobis(isobutyronitrile) (AIBN) as the photoinitiator, respectively. High molecular weight (HMW) poly(vinyl alcohol) (PVA) having number-average degree of polymerization (P _n ) of 3,900–7,800 and syndiotactic diad (S-diad) content of 52.5–54.0% could be prepared by complete saponification of synthesized linear poly(vinyl acetate) (PVAc) havingP _n of 5,900–9,400 obtained at conversion of below 30%.P _n of PVA using ADMVN was larger than that of PVA using AIBN. On the other hand, conversion of the former was smaller than that of the latter, and it was found that the initiation rate of the ADMVN was lower than that of AIBN. This could be explained by a fact that the rate of photolysis of AIBN is faster than that of ADMVN due to the higher quantum yield or dissociation rate constant of AIBN than that of ADMVN. TheP _n , syndiotacticity, and whiteness of PVA from PVAc polymerized at lower temperatures were superior to those of PVA from PVAc polymerized at higher temperatures.