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61.
A subcutaneous mass at the digit of the left-hind limb of a 12-year-old, male mongrel dog was examined. A white firm mass, approximately 1 x 2 cm in diameter, was excided surgically. Histopathologically, the mass formed multiple nodules consisting of mixed proliferation of round epithelioid cells arranged in cord or sheet-like structures and small spindle cells forming loose irregular bundles. The epithelioid cells often showed proliferation around the blood vessels. A few giant cells scattering in the neoplastic foci were observed. The neoplastic cells were positive for alpha-smooth muscle actin and vimentin, and were negative for cytokeratin (AE1/AE3), desmin, factor-VIII related antigen, S-100 protein, and neuron specific enolase. On the basis of these findings, this tumor was diagnosed as glomus tumor. Since the present neoplasm had neither recurrence nor distal metastasis during the 12 month after surgical resection, the biological natures of the present neoplasm are supposed to be benign.  相似文献   
62.
A cell line, MCO-Y4, was established from a mammary gland osteosarcoma of a 16-year-old female mongrel dog. Histopathologically the tumor was composed of osteoblastic cells with an osteoid meshwork and chondroid matrix. The mean doubling time of the cells at the 93rd passage was 32.39+/-4.66 hr. Immunohistochemically, the osteoblastic and chondroblastic cells were positive for bone morphogenetic protein (BMP)-2/4 and BMP receptor (BMPR) II. The cultured cells were spindle in shape during the growth and the confluent phases. No tumor matrix was detected in the culture dish by alcian blue staining or von-Kossa silver impregnation. MCO-Y4 cells on the chamber slides showed intense immunoreactivity for BMP-2/4 and BMPR II. Noggin, an antagonist for BMP-2/4, showed the growth inhibition on MCO-Y4 cells. In addition, fibronectin might be potential for stimulating growth of MCO-Y4 cells. When transplanted into severe combined immunodeficiency mice, the cells formed tumors consisting of solid proliferation of osteoblastic and fibroblastic cells with woven-bone trabeculae. These tumor cells were intensely positive for BMP-2/4 and BMPR II. Our results suggested that the cell line might be useful for studying the role of BMPs in canine osteosarcoma and the mechanism of ossification.  相似文献   
63.
Auxiliary subunits assist AMPA-type glutamate receptors   总被引:1,自引:0,他引:1  
Glutamate, the major excitatory neurotransmitter in the brain, acts primarily on two types of ionotropic receptors: alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and N-methyl-d-aspartate (NMDA) receptors. Work over the past decade indicates that regulated changes in the number of synaptic AMPA receptors may serve as a mechanism for information storage. Recent studies demonstrate that a family of small transmembrane AMPA receptor regulatory proteins (TARPs) controls both AMPA receptor trafficking and channel gating. TARPs provide the first example of auxiliary subunits of ionotropic receptors. Here we review the pivotal role that TARPs play in the life cycle of AMPA receptors.  相似文献   
64.
Activators of tissue proteolysis including Stachybotrys microspora triprenyl phenol (SMTP)-7 are a new class of agents that are expected to be effective for amelioration of chronic tissue destructive diseases. The present study was performed to examine whether SMTP-7 is effective for the amelioration or protection of early-stage IgA nephropathy (IgAN) induced by nivalenol (NIV) in female BALB/c mice. In Experiment 1, mice were administered NIV at 24 ppm in diet for 8 weeks, and during the NIV treatment, they were intraperitoneally injected with SMTP-7 (10 mg/kg) three times a week. In Experiment 2, mice were injected similarly with SMTP-7 during the last 4 weeks of a 16-week NIV treatment. Immunofluorescence analysis revealed an inhibitory effect of SMTP-7 on the glomerular deposition of IgA in Experiment 1; however, it was ineffective in Experiment 2. On the other hand, SMTP-7 did not affect the serum concentration of IgA in both experiments. These results suggest that SMTP-7 has a potential to decrease the progression of IgAN induced by NIV through inhibition of local accumulation of IgA in the glomerular mesangium, while it was ineffective for suppression of IgA production. On the other hand, SMTP-7 was found to be ineffective for already deposited IgA, suggesting that SMTP-7 may not be effective for ameliorating advanced IgAN.  相似文献   
65.
Recent analyses of Streptococcus suis isolates using multilocus sequence typing (MLST) suggested the importance of sequence type (ST) 1 and ST27 complexes for animal hygiene and public health. In this study, to investigate whether pilus-associated genes in S. suis can be used as novel genetic markers for important clonal groups, we examined the correlation between STs and putative pilus-associated gene profiles in S. suis. Genomic searches using sequenced genomes and sequence data determined in several isolates revealed the presence of at least four distinct putative pilus gene clusters in S. suis (srtBCD, srtE, srtF, and srtG clusters). On the basis of the presence or absence of genes in the four clusters, 108 S. suis isolates from various origins were classified into 12 genotypes (genotypes A–L). Genotypes A and B, which possessed srtBCD plus srtF clusters and srtF plus srtG clusters, respectively, were the most common in isolates from diseased pigs and humans, and 29.9% and 59.8% of the isolates belonged to genotypes A and B, respectively. In contrast, only 4.8% and 28.6% of isolates from healthy carriers were genotypes A and B, respectively. MLST analysis showed the associations of genotypes A and B with ST1 and ST27 complexes, respectively. In addition, srtBCD and srtG clusters were preferentially distributed to ST1 and ST27 complex members, respectively. These results suggest that profiling of selected pilus-associated genes could be used as an easy screening method to monitor isolates important for S. suis infection.  相似文献   
66.
Cushing's disease caused by pituitary corticotroph adenoma is a common endocrine disease in dogs. A characteristic biochemical feature of corticotroph adenomas is their relative resistance to negative feedback by glucocorticoids. In this study, we examined gene expression related to adrenocorticotropic hormone (ACTH) production and secretion, and the negative feedback by glucocorticoids in canine corticotroph adenoma. We used resected corticotroph adenomas from 10 dogs with Cushing's disease. In order to investigate the alteration of gene expression between corticotroph adenoma and normal corticotrophic cells, ACTH-positive cells in the anterior lobe were microdissected using a laser-capture microdissection system, and mRNA levels of proopiomelanocortin (POMC), corticotropin releasing hormone receptor 1 (CRHR1), glucocorticoid receptor (GR), mineralocorticoid receptor (MR), and 11 beta hydroxysteroid dehydrogenase (11HSD) type 1 and type 2 were determined using real-time RT-PCR. POMC, CRHR1, and 11HSD2 mRNA levels in corticotroph adenoma were greater than those in normal corticotrophic cells (POMC, 5.5-fold; CRHR1, 4.9-fold; 11HSD2, 4.2-fold, P<0.01, respectively). MR and 11HSD1 mRNA levels in corticotroph adenoma were lower than those in normal corticotrophic cells (MR, 2.2-fold; 11HSD1, 2.9-fold, P<0.01, respectively). GR mRNA levels did not differ between corticotroph adenoma and normal corticotrophic cells. Our results may help to understand the increased ACTH production and the resistance to negative feedback suppression by glucocorticoids in canine corticotroph adenomas. These changes in gene expression may have a role in the growth of canine corticotroph adenoma, and help elucidate the pathophysiology of dogs with Cushing's disease.  相似文献   
67.
The therapeutic effect of clindamycin on Eimeria pragensis (E. pragensis) infection in C57BL/6 mice was demonstrated by suppression of oocyst production and the appearance of degenerated endogenous stages of parasite in the intestine. Short-term clindamycin treatment, from 1 to 4 days or 4 to 8 days post infection (pi) at a dose of 800 mg/kg/day was effective to reduce clinical symptoms, oocyst production and schizogonic development. Interestingly, the short-term treatment schedules allowed the development of a measurable degree of protective immunity to challenge infection in the treated mice. In contrast, clindamycin treatment for the full 12 days period, which almost completely inhibited clinical symptoms and oocyst output, prevented the full development of protective immunity in the treated mice. All these data indicate that clindamycin is efficacious as an anti-eimerian agent and that both early and late endogenous developmental stages of E. pragensis exert a deep influence on the development of effective immunity to challenge infection.  相似文献   
68.
To know growth profiles of canine distemper virus (CDV) on Vero cells stably expressing canine signaling lymphocyte activation molecule (Vero-DogSLAMtag; Vero-DST cells), the propagation of three strains of CDV was tested in Vero-DST cells in comparison with parental Vero cells. Strain MD77 could grow well in both cell lines, but demonstrated no syncytium formation or indistinguishable rounding cytopathic effects (CPE) in Vero cells. Strains Onderstepoort and KDK-1 also grew well in Vero-DST cells with apparent syncytium CPE, while they grew less or no efficiently, respectively, in Vero cells. All three CDV strains demonstrated the peak titers, in Vero-DST cells before reaching to an extensive CPE and drastic decrease of titers at/after full CPE. Immunohistochemistry revealed that viral antigens of all CDV strains were found exclusively in the syncytia in Vero-DST cells, while in Vero cells, viral antigen was identified in their single cells for strain MD77 but none for other strains. Thus, every strain of CDV could grow well in Vero-DST cells and behaved differently against Vero cells. These results would be of practical value for workers of CDV because 1) In Vero-DST cells, by observation of distinct syncytium CPE, the highest titer or the best growth of virus could be identified; 2) In Vero cells, various CDV strains could be readily classified after propagation in Vero-DST cells.  相似文献   
69.
Hepatitis C virus (HCV) is a major causative agent for chronic liver diseases leading to hepatocellular carcinoma (HCC) and has also been suggested to be a possible etiologic factor for different lymphoproliferative diseases, including mixed cryoglobulinemia (MC) and B-cell non-Hodgkin's lymphoma (NHL). To understand the roles of HCV core protein in the pathogenesis of HCV related diseases, we produced two lines of the transgenic mice (HC82310 and HC9053) that express the HCV core transgene. One of the lines, HC9053, developed malignant lymphoma (ML, follicular center cell type) with a high frequency (80%) at the ages over 20 months. Hepatocellular adenoma was also observed in this line of transgenic mouse. We demonstrated expression of HCV core protein and mRNA in the liver of transgenic mice, and also detected the core mRNA in the enlarged lymph nodes of the transgenic mice which developed ML. These results suggest that the core protein may play an important role in the development of ML, and that the HC9053 transgenic mice provide suitable models for understanding the mechanism of HCV-related lymphoproliferative diseases.  相似文献   
70.
A solitary brain mass of a 4-month-old miniature dachshund showing seizure-like neurological signs was examined histopathologically. At necropsy a white tumor mass, replacing the thalamus, approximately 1.5 cm in diameter, was found. There was cystic space filled with yellowish pale fluid in the central area of the tumor mass. Histopathological examination revealed that the mass consisted of irregularly arranged well-differentiated neuronal and glial cells, and multifocal mineral deposits. The neuronal cells had a large clear nucleus and various amount of Nissl substances in the cytoplasm. Some neural cells were bi-nucleated. Neither mitotic figures nor proliferating cell nuclear antigen (PCNA)-positive nuclei was found in the neuronal cells. Immunostaining for glial fibrillary acidic protein (GFAP) revealed diffuse proliferation of GFAP-positive glial cells and their processes, while these glial cells did not show apparent cellular atypism, mitotic activity, or PCNA-immunoreactivity. Accordingly, the present tumor was diagnosed as ganglioglioma, and hamartomatous histogenesis might be possible.  相似文献   
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