Use of a staphylococcal vaccine to reduce prevalence of mastitis and lower somatic cell counts in a registered Saanen dairy goat herd

This investigation evaluated the efficacy of a bacterin in reducing the prevalence of staphylococcal mastitis and somatic cell counts (SCC) in a dairy goat herd. Does were vaccinated or left as controls, and the levels of mastitis and SCC monitored over 18 months. Staphylococcus caprae (42.5%), S. xylosus (15.1%), and S. simulans (10.0%) were the predominant causes of intramammary infections (IMI). The infection rate was 1.64 IMI/doe among vaccinates, which tended to be lower (P < 0.12) than controls (2.67 IMI/doe). The spontaneous cure rate of IMI after immunization was 1.28 cures/doe in vaccinates, which was higher than controls (0.6 cures/doe; P < 0.043). Average SCC of milk samples from vaccinates tended to be lower than that of controls (1274 × 10³/ml vs. 1529 × 10³/ml, respectively) (P < 0.10). Results support the continued study of mastitis vaccines for use in managing staphylococcal mastitis and SCC in dairy goats.     

Use of stem cells in equine musculoskeletal disorders

Stem cell therapies for musculoskeletal disorders are becoming commonplace in the horse. In order to decipher the many options available for stem cell therapy and interpret results of accumulating experimental and clinical data, practitioners should have a basic understanding of stem cells.     

The use of quantitative PCR to detect Felis catus papillomavirus type 2 DNA from a high proportion of queens and their kittens

Squamous cell carcinomas are common feline skin cancers that have been associated with infection with Felis catus papillomavirus type 2 (FcaPV-2). Currently, little is known about the epidemiology of FcaPV-2 infection. The aim of this study was to develop a real-time PCR assay to quantify FcaPV-2 DNA in plucked hairs and skin swabs from 11 healthy breeding queens and their kittens. Samples were taken prior to kittening and then 2, 7 and 28 days after kittening to determine the age at which the kittens were first exposed to the virus. FcaPV-2 DNA was amplified from all of the queens and from 91% of the kittens at 2 days of age. There was a wide range in the quantity of FcaPV-2 DNA detected, from 1 to 92,520 copies per swab, and from 0.01 to 234 copies per copy of reference gene DNA in the hair plucks. The quantity of FcaPV-2 DNA detected in samples collected from the kittens was strongly correlated to that of their respective queens and the mean viral DNA load was similar for cats within a household but varied significantly between households. This is the first time that quantitative PCR has been used to detect FcaPV-2 DNA and the results suggest that the virus is ubiquitous but there is a wide variation of viral DNA loads. Kittens appear to be exposed to FcaPV-2 early in life, presumably from direct contact with their queen. These results are important when determining if FcaPV-2 infection of cats is preventable.     

中国广东家蚕微粒子孢子在Antheraea eucalypti细胞系的感染增殖

将中国广东的Ｎｏｓｅｍａ ｂｏｍｂｙｃｉｓ ＣＧＳ,用０２ｍｏｌ／ＬＫＯＨ 处理后,接种感染Ａ．ｅｕｃａｌｙｐｔｉ 细胞系。孢子的发芽率达８７％ ,在Ａ．ｅｕｃａｌｙｐｔｉ 细胞初期感染率为２７ ％ 。发育各阶段具２ 核,可观察到短极丝孢子和二次感染体形成,孢子芽母细胞按二分裂形成２ 个双核的孢子芽,具典型 Ｎｏｓｅｍａ 属特征。Ｎｏｓｅｍａｂｏｍｂｙｃｉｓ ＣＧＳ 生物学特性、血清学类型与日本Ｎｏｓｅｍａ ｂｏｍｂｙｃｉｓ ＮＩＳ００１ 大致相同,但孢子大小、裂殖体的形态、在Ａ．ｅｕｃａｌｙｐｔｉ 细胞寄生的细胞感染率、每个细胞的产孢数,２ 种微孢子虫却有差异。     

甲型肝炎病毒免疫控制研究进展

对甲型肝炎病毒(HAV)发病机理和免疫调控的研究近年来重新受到关注。在发展中国家感染者的平均年龄增加,导致机制尚不明确的更严重的肝炎。而且,从HAV和丙型肝炎病毒(HCV)的免疫对比来看,这两种正链RNA病毒感染结果完全不同。HCV比HAV复制效率低,导致HCV蛋白表达量低,因此对IFN信号传导的拮抗作用较低。有研究发现循环的HAV病毒颗粒隐藏在膜里,导致先天免疫和抗体介导中和作用的激活。同时还考虑到CD4^+辅助T细胞对CD8^+细胞毒性T细胞对抗病毒免疫和肝损伤的作用,提出了一种非细胞毒性的HAV感染免疫控制模型。     

BRCA1基因多态性及其与奶牛乳房炎抗性的相关性研究

为了研究BRCA1基因突变与荷斯坦奶牛体细胞数和体细胞评分的关系,试验通过对BRCA1基因外显子13、14进行克隆、序列比对和挖掘已有突变的方法确定该基因的多态位点,采用SNaPshot技术检测了BRCA1基因25025 T>A和46126 G>T突变位点在北京郊区荷斯坦奶牛群体中的分布,并对突变位点与体细胞数和体细胞评分进行了关联分析。结果表明,荷斯坦奶牛BRCA1基因2个位点均检测到3种基因型,其中25025 bp位点TT基因型为优势基因型,46126 bp位点GT基因型为优势基因型。25025 bp位点AA基因型个体体细胞数(P<0.05)和体细胞评分(P<0.01)都显著低于TT和TA基因型;46126 bp位点TT基因型个体体细胞数显著低于GG和GT基因型个体(P<0.05),但3种基因型个体体细胞评分无显著差异(P>0.05)。本研究结果初步表明,BRCA1基因25025和46126 bp位点可作为中国荷斯坦牛乳房炎抗性的标记辅助选择。     

A novel MCT1 and MCT4 dual inhibitor reduces mitochondrial metabolism and inhibits tumour growth of feline oral squamous cell carcinoma

Monocarboxylate transporters (MCTs) support tumour growth by regulating the transport of metabolites in the tumour microenvironment. High MCT1 or MCT4 expression is correlated with poor outcomes in human patients with head and neck squamous cell carcinoma (HNSCC). Recently, drugs targeting these transporters have been developed and may prove to be an effective treatment strategy for HNSCC. Feline oral squamous cell carcinoma (OSCC) is an aggressive and treatment‐resistant malignancy resembling advanced or recurrent HNSCC. The goals of this study were to investigate the effects of a previously characterized dual MCT1 and MCT4 inhibitor, MD‐1, in OSCC as a novel treatment approach for feline oral cancer. We also sought to determine the potential of feline OSCC as a large animal model for the further development of MCT inhibitors to treat human HNSCC. In vitro, MD‐1 reduced the viability of feline OSCC and human HNSCC cell lines, altered glycolytic and mitochondrial metabolism and synergized with platinum‐based chemotherapies. While MD‐1 treatment increased lactate concentrations in an HNSCC cell line, the inhibitor failed to alter lactate levels in feline OSCC cells, suggesting an MCT‐independent activity. In vivo, MD‐1 significantly inhibited tumour growth in a subcutaneous xenograft model and prolonged overall survival in an orthotopic model of feline OSCC. Our results show that MD‐1 may be an effective therapy for the treatment of feline oral cancer. Our findings also support the further investigation of feline OSCC as a large animal model to inform the development of MCT inhibitors and future clinical studies in human HNSCC.     

In vitro neuronal and osteogenic differentiation of mesenchymal stem cells from human umbilical cord blood

Mesenchymal stem cells (MSCs) have the capabilities for self-renewal and differentiation into cells with the phenotypes of bone, cartilage, neurons and fat cells. These features of MSCs have attracted the attention of investigators for using MSCs for cell-based therapies to treat several human diseases. Because bone marrow-derived cells, which are a main source of MSCs, are not always acceptable due to a significant drop in their cell number and proliferative/differentiation capacity with age, human umbilical cord blood (UCB) cells are good substitutes for BMCs due to the immaturity of newborn cells. Although the isolation of hematopoietic stem cells from UCB has been well established, the isolation and characterization of MSCs from UCB still need to be established and evaluated. In this study, we isolated and characterized MSCs. UCB-derived mononuclear cells, which gave rise to adherent cells, exhibited either an osteoclast or a mesenchymal-like phenotype. The attached cells with mesenchymal phenotypes displayed fibroblast-like morphologies, and they expressed mesenchym-related antigens (SH2 and vimentin) and periodic acid Schiff activity. Also, UCB-derived MSCs were able to transdifferentiate into bone and 2 types of neuronal cells, in vitro. Therefore, it is suggested that the MSCs from UCB might be a good alternative to bone marrow cells for transplantation or cell therapy.