Involvement of PKA signalling in anti‐inflammatory effects of chitosan oligosaccharides in IPEC‐J2 porcine epithelial cells

Weaning is characterized by intestinal inflammation, which is a big challenge in pig industry. Control of intestinal inflammation is important for improvement of growth performance and health. Therefore, the study was focused on the anti‐inflammatory activity of low‐molecular‐weight chitosan oligosaccharide (LCOS) in a porcine small intestinal epithelial cell line (IPEC‐J2). The results showed that TNF‐α, as inflammation inducer, significantly upregulated the mRNA expression of IL‐8 and MCP‐1. Afterwards, LCOS significantly attenuated mRNA expression of IL‐8 and MCP‐1 induced by TNF‐α in the cells. Mannose (MAN), as ligand of mannose receptor, had no effect on the anti‐inflammatory activity of LCOS, which suggested that mannose receptor may not involve in the anti‐inflammatory activity of LCOS in IPEC‐J2 cells. Interestingly, N‐[2‐(p‐bromocinnamylamino)ethyl]‐5‐isoquinolinesulfonamide 2HCl hydrate (H89), as PKA (protein kinase A)‐specific inhibitor, reversed the mRNA expression of IL‐8 when co‐cultured with LCOS. Furthermore, LCOS concentration dependent downregulated the mRNA expression of claudin‐1 compared with TNF‐α treatment. However, the trans‐epithelial electric resistance (TEER) was not affected by LCOS when co‐cultured with TNF‐α in 3 hr. In conclusion, LCOS have a potent anti‐inflammatory activity, and as a feed additives, may be useful for the inhibition of inflammatory process in weaning period of pigs with intestinal inflammation occurring.     

DIAGNOSIS AND SURGICAL TREATMENT OF A TRANSITIONAL CELL CARCINOMA IN THE BLADDER APEX OF A PET RABBIT (ORYCTOLAGUS CUNICULUS)

A 6-year-old, 1.9-kg female spayed lop-eared European rabbit (Oryctolagus cuniculus) was evaluated for acute hematuria and inappropriate urination and defecation of less than 12-hours duration. Abdominal ultrasonography revealed a suspected bladder mass. Ultrasound-guided cystocentesis was performed and the results of the urinalysis were unremarkable. An abdominal exploratory surgery revealed a nodular cystic mass at the cranial ventral apex of the bladder wall which measured 0.5 cm × 0.5 cm. Based on histopathologic evaluation, excision of the neoplasm was complete and the mass was diagnosed as transitional cell carcinoma of the bladder. This case suggests that urinary bladder transitional cell carcinoma should be considered in pet rabbits presenting with similar clinical signs.     

AVIAN CHOLERA IN CANARIES (SERINUS CANARIA): REVIEW OF 2 OUTBREAKS

This report describes the evaluation of 2 avian cholera outbreaks in two canary (Serinus canaria) aviaries located in southern Brazil. The first outbreak had its onset after a thermal inversion, when the canaries exhibited clinical signs that included dyspnea, conjunctivitis, cyanosis, and death. The clinical progression of the disease, on average, lasted 2 days, and lead to a 40% loss of birds within the aviary. In the second outbreak the canaries also went through a thermal inversion, ending up with several cases of sudden death (60% of mortality) in a period of 24 hours. Canaries from both aviaries were submitted for microbiological evaluation, where isolates of Pasteurella multocidamultocida, which were resistant to sulfonamide, oxytetracycline, and enrofloxacin, were identified. After the analyzing the antimicrobial susceptibility profiles, canaries in both aviaries were treated with amoxicillin. Following 3 weeks of treatment, the outbreaks were controlled.     

H6N6亚型禽流感病毒N6基因的原核表达与多克隆抗体制备

为表达H6N6亚型禽流感病毒（avian influenza virus,AIV）神经氨酸酶（NA）蛋白,并制备多克隆抗体,本试验根据GenBank中AIV N6基因序列（登录号：MG434500）设计特异性引物,对贵州地区分离的H6N6亚型AIV贵州株进行N6基因PCR扩增,将其克隆到原核表达载体pET-32a （+）中,构建重组原核表达载体pET-32a-N6,转化大肠杆菌BL21（DE3）感受态细胞,经IPTG诱导表达His-N6重组蛋白,将诱导产物超声破碎离心后,利用镍柱对重组蛋白进行纯化,并利用SDS-PAGE和Western blotting对表达蛋白进行双重鉴定,将纯化后的重组蛋白免疫新西兰大白兔制备多克隆抗体,并通过间接ELISA检测其效价。结果显示,AIV贵州株N6基因编码区长1 380 bp,可编码459个氨基酸,其中175－207 bp缺失33个核苷酸;重组质粒pET-32a-N6经双酶切鉴定分别获得大小为5 900 bp左右的载体条带和1 380 bp左右的目的基因条带,成功构建了pET-32a-N6重组质粒;蛋白超声破碎后经SDS-PAGE发现,重组蛋白主要存在于沉淀中,以包涵体形式存在,蛋白分子质量约为70 ku,与预期结果一致;纯化后的重组蛋白经SDS-PAGE和Western blotting双重鉴定,均在70 ku处出现条带,说明纯化的蛋白为重组蛋白pET-32a-N6,表达产物具有免疫学活性,包涵体经变性、复性处理,重组表达蛋白分别被His抗体和兔源抗N6多克隆抗体所识别。间接ELISA检测其效价高于1∶3 200。以上结果表明,试验成功克隆、表达了H6N6亚型AIV的N6基因,所制备的N6蛋白多克隆抗体具有良好的免疫活性,能被His抗体和兔源抗N6多克隆抗体所识别。     

Avian infectious bronchitis virus in Africa: a review

Infectious bronchitis virus (IBV) is worldwide in distribution, highly infectious, and extremely difficult to control because it has extensive genetic diversity, a short generation time, and a high mutation rate. IBV is a Gammacoronavirus, single-stranded, and positive-sense RNA virus. Avian infectious bronchitis is well studied in European countries with identification of a large number of IBV variants, whereas in African countries epidemiological and scientific data are poor and not updated. However, previous studies reported that an IBV variant continues to appear regularly in Africa, as currently described in Morocco. No cross-protection between IBV strains was reported, some being unique to a particular country, others having a more general distribution. This review aims to provide a general overview on IB disease distribution in African countries and an update on the available studies of IBV variants in each country.     

禽流感文献的分析

利用文献计量学方法,统计分析了1975-2004年间Web of Science收录的禽流感（Avian Influenza）研究文献,探讨了禽流感文献研究的年代分布、语种、期刊分布、作者、文献类型和主题类目。     

禽腺病毒江苏分离株的细胞培养特性

为进一步研究的生物学特性,应用鸡胚成纤维细胞(CEF)和鸡胚肾细胞(CEK)培养禽腺病毒江苏分离株,进行培养特性、血凝特性、理化特性、超薄切片观察和PCR检测。实验结果表明,CEF感染病毒后没有出现病变。CEK感染病毒后则表现出很强的聚集性并形成细胞团,有的成束状,最后脱落;Reed-Muench方法测得其TCID50为每0．1mL 10^-5.4。CEK核内存在大量70～80nm、呈典型的晶格状排列的腺病毒颗粒。     

禽流感病毒H9亚型血凝抑制试验抗原国家参考品的研制

按照国家一级标准物质求,研制了一批禽流感病毒H9亚型血凝抑制试验抗原国家参考品,批号为200901。对其物理性状、无菌、效价、特异性、水分、真空度、均一性、稳定性等进行了测定,各项指标均符合求。经过8家单位对其协作标定,并经统计学分析,该批抗原血凝效价为1：（460±80）,最终定值为1：400。该禽流感病毒H9亚型血凝抑制试验抗原可以作为国家参考品。     

基于RED5的可视化农业科技推广系统研发

针对农业科技推广中农业专家少、农民文化水平普遍偏低的问题,基于J2EE框架,以开源的RED5作为流媒体服务器,并利用网络和流媒体技术,研发出了可视化农业科技推广平台,基于B/S模式能够减少客户端农户的操作负担,同时为农户提供专家在线和专家离线的双重服务,为农户和农业专家之间架起一道直接沟通     

禽流感检测能力比对试验的结果分析

对40份盲样采用琼脂扩散试验（AGP）、血凝抑制试验（HI）和反转录聚合酶链反应（RT-PCR）进行了检测。结果表明,在AGP试验中K1～K4盲样为禽流感抗体阳性,K5为阴性样本。在HI试验中,AJ5、AJ9、AJl3、AJl7、AJ23盲样为禽流感H5亚型抗体阳性;AJ4、AJ6、AJl2、AJl6、AJ2。为H7亚型抗体阳性;AJ2、AJl0、AJl4、AJl9、AJ22为H9亚型抗体阳性;其它盲样为阴性。在RT-PCR检测中,B20”B217、B232、B241盲样被扩增出分子长为229bp和372bp两条特异性的DNA片段,确定为H5亚型禽流感病毒,其它盲样为阴性。