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Currently, antimicrobial-resistant staphylococci, particularly methicillin-resistant Staphylococcus pseudintermedius (MRSP), are frequently isolated from canine superficial pyoderma in Japan. However, little is known regarding the nasal prevalence of MRSP in pet dogs. Here, we determined the prevalence of antimicrobial-resistant staphylococci in nares and affected sites of pet dogs with superficial pyoderma. Of the 125 nares and 108 affected sites of pet dogs with superficial pyoderma, 107 (13 species) and 110 (eight species) staphylococci strains, respectively, were isolated. The isolation rate of S. pseudintermedius from pyoderma sites (82/110 strains, 74.5%) was significantly higher than that from nares (57/107 strains, 53.3%) (P<0.01). Notably, the prevalence of MRSP (18/57 strains, 31.6%) in nares was equivalent to that in pyoderma sites (28/82 strains, 34.1%). Furthermore, the phenotypes and genotypes of antimicrobial resistance in MRSP strains from nares were similar to those from pyoderma sites. Our findings revealed that the prevalence of antimicrobial-resistant staphylococci in the nares of pet dogs with superficial pyoderma is the same level as that in affected sites. Therefore, considerable attention should be paid to the antimicrobial resistance of commensal staphylococci in companion animals.  相似文献   
3.
To elucidate the molecular dynamics of HP1beta in mouse preimplantation embryos, we examined the localization, dynamics, and mobility of HP1beta in the (pro)nucleus by live cell imaging. Time-lapse observation revealed that the chromatin association of HP1beta is regulated in a cell cycle-dependent manner. HP1beta was localized in the interphase nucleus and was dynamically dissociated from the nucleus during the metaphase stage. The HP1beta assembly and clustered heterochromatin structure were both found in the nuclei of 2-cell and later-stage embryos. Moreover, fluorescent recovery after photobleaching analysis implied that HP1beta is more freely mobile in the pronucleus of the 1-cell embryo than in the 4-cell nucleus. These results suggest that the chromatin configuration may be regulated by the stability and mobility of chromatin-associated proteins including HP1beta during early embryonic stages.  相似文献   
4.
The onset of severe injury to the superficial digital flexor tendon (SDFT) is extremely difficult to predict from slight changes in ultrasonographic findings in cases with no apparent clinical signs. This study investigated the relationship between an increased cross-sectional area (CSA) or edema in the subcutaneous tissue around the tendon and the subsequent onset of severe SDFT injury in Thoroughbred racehorses. Horses were classified into three groups based on ultrasound diagnosis (USD) findings: Group A included cases with enlarged tendons; Group B included cases with tendons of normal size but with prominent edema in the peritendinous tissue; and Group C (control group) included cases with no abnormal USD findings. The incidence of subsequent severe tendon injury was significantly higher in the horses in Groups A (25.7%, 28/101) and B (28.3%, 65/212) than in those in Group C (4.9%, 2/41). There were no significant differences in the median period and the median number of races from the first examination to the subsequent tendon injury between Groups A (140 days, 1 race) and B (120 days, 1 race). The results of this study revealed that horses with increased CSA and peritendinous edema are likely to suffer a subsequent severe tendon injury. Also, these two USD findings, i.e., increased CSA and peritendinous edema, indicate the risk of onset of severe SDFT injury.  相似文献   
5.
The current study investigated the effects of oyster mushroom Pleurotus ostreatus, extract on immunological and hematological parameters of rainbow trout, Oncorhynchus mykiss. The fish were fed diets containing 0 (control), 1, and 2% supplementation of the oyster mushroom extract for 6 wk. Blood samples were collected weekly for the first 6 weeks. After 6 wk of feeding, the fish were challenged with Lactococcus garvieae and mortality was recorded. The results of this study showed that feeding rainbow trout an oyster mushroom extract–supplemented diet stimulated phagocytic activity of phagocytic cells, lysozyme activity, and myeloperoxidase activity in serum, but it did not significantly affect the total serum immunoglobulin level. At the same time, a significant increase was found in the number of neutrophils, monocytes, and total white blood cells. Fish fed the diet supplemented with oyster mushroom extract showed reduced mortalities following L. garvieae infection compared with controls. These results show that supplementation of fish diets with oyster mushroom extract at 1 and 2% concentrations significantly imrpoves hematological parameters and modulates the immune response against L. garvieae in rainbow trout.  相似文献   
6.
A 10-year-old, female shih tzu was diagnosed as having myelodysplastic syndrome (MDS) based on the presence of a nonregenerative anemia, dysplastic changes in the three hematopoietic cell lines, a normal to hypercellular bone marrow, and less than 30% blast cells of all nucleated cells in the bone marrow. Low-dose aclarubicin, a differentiation-induction therapy for MDS and atypical leukemias in humans, was administered. Hematological improvement was observed, and the dog lived for 809 days after the first presentation.  相似文献   
7.
The production and secretion of Salmonella enteritidis whole cell antigen-specific antibodies in the oviducts and in the serum of laying hens experimentally infected with Salmonella enteritidis, was analyzed by ELISA. The dynamics of the antibody levels in the oviducts were identical to that in the serum. Subclasses of antibodies (IgA, IgG, and IgM) in the infected hens were found to increase significantly (p < 0.01) compared to those in the control uninfected hens throughout the experiment. IgG and IgM levels in both oviducts and in sera reached to a peak by 14 days post-inoculation, and remained elevated throughout. The secretion of IgA seemed to be transient since the IgA levels increased to a peak 7 days after both primary and secondary inoculations, and declined rapidly. The elevated levels of antibodies were followed by partial clearance of Salmonella organisms from the oviducts. The present results indicate a significant local immune reaction against the Salmonella infection and suggest an association of the local antibodies with the clearance of Salmonella from the oviducts at least partially.  相似文献   
8.
We examined contact-mediated effects of chicken thymic stromal cells (TSC) on thymocyte differentiation by co-cultivation of these cell populations. The primary cultures of TSC isolated from thymus mainly have consisted of epithelial cells which were polygonal in shape, possessed long processes and expressed MHC class II antigen. When thymocytes were co-cultured with TSC, 60% to 70% of thymocytes attached to TSC and some of them engulfed underneath TSC. These attached thymocytes were CD4-CD8- and CD4+CD8+ subsets and expressed alpha/beta TCRhigh or gamma/delta TCRlow. Some of the thymocytes attaching to TSC showed an increase of intracellular and nuclear density, fragmentation of cytoplasm and nuclei, and DNA fragmentation. And also, thymocytes attaching to TSC contained a higher percentage of cycling (S and G2 + M phase) cells than nonattaching cells. These results indicate that specific subsets in thymocytes selectively bind to TSC and undergo apoptotic death or proliferation because of interaction with TSC. Chicken TSC may play an important role in thymic differentiation by direct contact within the thymus as in mammals.  相似文献   
9.
The effects of concurrent cage contamination with Salmonella typhimurium and Eimeria tenella on the establishment of salmonella infection in day-old chickens were investigated. Chickens were divided into five groups: uninfected recipient birds placed in a cage contaminated by donor birds infected with E. tenella and S. typhimurium; E. tenella-infected recipients placed in a cage contaminated by S. typhimurium-infected donors; uninfected recipients placed in a cage contaminated by S. typhimurium-infected donors; E. tenella-infected recipients placed in a cage contaminated by uninfected donors; and uninfected recipients placed in a cage contaminated by uninfected donors. Three identical trials were conducted. Recipient birds were necropsied 4, 7, and 11 days after caging. In the cage where donor birds infected with both organisms had been reared, S. typhimurium counts in feces and number of feces positive for S. typhimurium were significantly (P less than 0.05) greater than those in the other cages on days 0, 4, and 7 after caging. Moreover, in this cage, more chicks died, counts of S. typhimurium in cecal contents were greater, and more birds were positive for S. typhimurium than in the other groups. This suggests that S. typhimurium infection in day-old chickens is enhanced in cages contaminated with E. tenella and S. typhimurium compared with infection in cages contaminated with S. typhimurium alone.  相似文献   
10.
Cell-mediated immune protection in chickens against Pasteurella multocida   总被引:2,自引:0,他引:2  
Immune protection by cellular immunity in chickens against Pasteurella multocida was investigated by in vivo and in vitro experiments using spleen cells and culture supernatants of immunised chickens. Intraperitoneal or intravenous transfer of immune splenic cells into normal chickens induced transmission of an as effective protection as that exhibited in immunised chickens. Immune protection was also obtained by intravenous treatment of chickens with culture supernatant fluid from immune splenic cells of hormonally bursectomised chickens. The in vitro experiment showed that intracellular bacterial proliferation was inhibited in peritoneal macrophages from immunised chickens, or from normal chickens sensitised with culture supernatant fluid of immune splenic cells, and the macrophages were protected from disruption by infection. Peritoneal macrophages sensitised with culture supernatant fluid from unimmunised splenic cells, or peritoneal macrophages from unimmunised chickens, allowed considerable intracellular proliferation of bacteria with almost complete breakdown of the macrophages within 24 hours after bacterial challenge. These data suggest that the protective immunity of chickens against P multocida was dependent on cell-mediated immunity by mediators such as the macrophage activating factor from T lymphocytes.  相似文献   
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