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11.
The expression pattern of CD44 was studied in the rat testis following ischemia/reperfusion (I/R) injury to elucidate the possible role of the CD44 adhesion molecule in acute experimental testicular torsion. Western blot analysis showed that CD44 expression began to increase significantly 24 hr after reperfusion, compared with the normal control; the increased expression persisted until 96 hr after I/R. Immunohistochemistry showed that, in the normal testis, CD44 was constitutively expressed mainly in ED2-positive resident macrophages in the interstitial space. After I/R, the majority of inflammatory cells in the interstitial space surrounding the damaged tubules were ED1-positive macrophages that were CD44-positive. These findings suggest that the significant increase in CD44 expression that occurs during the delayed phase after reperfusion originates from infiltrating macrophages possibly in anticipation of the migration and adhesion of additional macrophages into the affected testis.  相似文献   
12.
Basosquamous carcinoma (BSCC) is a rare malignancy, primarily composed of basal cells with foci of squamous differentiation. It is considered to be histologically an intermediate type between basal cell carcinoma and squamous cell carcinoma, and is known to have aggressive behaviors. BSCC occurred in a 17-year-old female minipin with a history of surgical excision for a mammary tumor. The right upper hindlimb was severely enlarged to 8 x 5 cm. Cross-section showed a homogenous white to yellow-white mass compressing the surrounding muscular tissues. The tumor metastasized also to the lungs, heart, abdominal cavity, liver and salivary gland. Microscopically, basaloid cells were crowded into solid nests or lobules separated by well-developed fibrous tissues with occasional keratinizations. Since there was no skin lesions, the tumor is assumed to be originated from the formerly present tumor in mammary gland. To our literature review, this case is the first BSCC with systemic metastasis in a dog.  相似文献   
13.
This study was performed to evaluate the effects of conditioned media (CM) from human amniotic epithelial cells (HAECs) on the corneal wound healing process. Eighteen rabbits (36 eyes) were used and randomly assigned to three groups according treatment: CM from HAECs (group 1), vehicle alone (group 2), and saline (group 3). Corneal alkali injuries were induced with 1 N sodium hydroxide. Each reagent used for treatment evaluation was injected into the dorsal bulbar subconjunctiva and the area of the corneal epithelial defect was measured every other day. Two animals from each group were euthanized at a time on days 3, 7, and 15, and the cornea was removed for histological examination. The sum of the epithelial defect areas measured on day 0 to day 6 as well as day 0 to day 14 in group 1 was significantly smaller than those of other groups. Histological examination revealed that the group 1 corneas had less inflammatory cell infiltration and showed more intact epithelial features compared to the other groups. These results suggest that CM from HAECs promote corneal wound healing in rabbits.  相似文献   
14.
Carbon nanotube (CNT)/magnetite (Fe3O4) nanocomposites were successfully fabricated by nanocoating. When the CNT/Fe3O4 nanocomposites were added to a carbonyl (CI) based magnetorheological fluid (MRF), the magnetic rheological properties of the MRF were enhanced. Such enhancement in magnetic rheological properties of the CI-CNT/Fe3O4 MRF is considered to be attributable to both the superparamagnetic property of the magnetic layer covering the CNT surface and the high length to diameter ratio of the CNT/Fe3O4 nanocomposite. Impact properties for CI-CNT/Fe3O4 MRF treated Kevlar fabrics were also tested, and improved impact properties were observed with external magnetic fields compared to CI-MRF treated Kevlar fabrics.  相似文献   
15.
In the present study, the in vitro and in vivo anti-inflammatory effects of the sulfated polysaccharides isolated from Sargassum fulvellum (SFPS) were evaluated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results indicated that SFPS improved the viability of LPS-stimulated RAW 264.7 macrophages from 80.02 to 86.80, 90.09, and 94.62% at the concentration of 25, 50, and 100 µg/mL, respectively. Also, SFPS remarkably and concentration-dependently decreased the production levels of inflammatory molecules including nitric oxide (NO), tumor necrosis factor-alpha, prostaglandin E2, interleukin-1 beta, and interleukin-6 in LPS-treated RAW 264.7 macrophages. In addition, SFPS significantly inhibited the expression levels of cyclooxygenase-2 and inducible nitric oxide synthase in LPS-treated RAW 264.7 macrophages. Furthermore, the in vivo test results indicated that SFPS improved the survival rate of LPS-treated zebrafish from 53.33 to 56.67, 60.00, and 70.00% at the concentration of 25, 50, and 100 µg/mL, respectively. In addition, SFPS effectively reduced cell death, reactive oxygen species, and NO levels in LPS-stimulated zebrafish. Taken together, these results suggested that SFPS possesses strong in vitro and in vivo anti-inflammatory activities, and could be used as an ingredient to develop anti-inflammatory agents in the functional food and pharmaceutical industries.  相似文献   
16.
Oxidative stress-induced neuronal cell loss is considered to be the major mechanism underlying the pathogenesis of neurodegenerative diseases, which could be induced by a high concentration of glutamate. In this study, sargachromenol (SC) was isolated from a marine brown seaweed Sargassum horneri (S. horneri) and its neuroprotective effects against glutamate-induced oxidative stress in HT22 cells were investigated. An MTT assay was applied to assess the cytotoxicity of the SC, and the efficacies of SC were determined by flow cytometry, an analysis of ROS production, quantitative Real-Time PCR, and the Western blot assay. Our results showed that the pretreatment of SC reduced glutamate-induced apoptosis in HT22 cells via inhibiting the sub-G1 population, DNA fragmentation, and nuclear condensation, as well as up-regulating anti-apoptotic protein (Bcl-2) and down-regulating apoptotic proteins (Bax, p53, cleaved-PARP, caspase-3, caspase-9, and cytochrome c). Additionally, SC attenuated glutamate-induced oxidative stress by suppressing mitogen-activated protein kinases (MAPKs;ERK, JNK, and p38) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling (IκBα and NF-κB p65), while activating nuclear factor erythroid-2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) signaling (Nrf2; HO-1, and NQO-1). Our results suggest that SC could be used as a pharmacological candidate for the prevention and treatment of neurodegenerative diseases.  相似文献   
17.
Vibrio anguillarum is a major pathogenic bacterium that causes vibriosis and septicemia in fish and shellfish. In this study, we identified the groESL genes, which encode bacterial chaperonins, from V. anguillarum. The groE gene cluster consisted of a 291-bp groES gene, a 69-bp intergenic spacer region, and a 1,635-bp groEL gene order. Sequence analysis with the groESL gene of Vibrio species exhibited that the groEL gene was more species-specific and suitable than the groES gene for V. anguillarum detection. Owing to the difficulty in distinguishing V. anguillarum from the closely related V. ordalii, we compared the sequences of groEL from V. anguillarum and the groEL homolog hsp60 from V. ordalii, in order to design a primer set based on a region dissimilar between the two. PCR with the groEL primer set produced a clear 195-bp amplicon in six serotypes of V. anguillarum, whereas 23 Vibrio species of 39 samples, including V. ordalii, and 10 species of enteric bacteria gave no bands. PCR using the groEL primers also amplified a unique product from V. anguillarum-infected flounder and oyster tissues. These results demonstrate that the groEL-target PCR assay is a sensitive and species-specific tool for the detection of V. anguillarum infection.  相似文献   
18.
The expression of caveolin-1 and -2 in the retina was examined; Western blot analysis showed that both were present. Immunohistochemistry indicated that caveolin-1 was expressed in the majority of retinal layers, including the ganglion cell layer, inner plexiform layer, outer plexiform layer, and in the vascular endothelial cells of the retina. Caveolin-2 was primarily immunostained in the vessels, but in a few other elements as well. This is the first demonstration of caveolin differential expression in the retina of rats, and suggests that caveolin plays an important role in signal transduction in glial cells and neuronal cells.  相似文献   
19.
Induced pluripotent stem cells (iPSCs) are thought to be highly beneficial in the field of regenerative medicine and are believed to overcome immunogenic barriers to cell transplantation. However, issues remain regarding their safety and efficiency for medical use. Furthermore, some recent reports have suggested that iPSCs could be targeted by the autologous immune system. To promote practical applications of iPSCs, in depth research using appropriate animal models is needed and porcine species appear to provide an ideal model. Recent studies have focused on the generation of porcine iPSC cells, but no investigations of their immunological properties have been conducted to date. In the present study, we generated putative iPSCs from porcine somatic cells and measured major histocompatibility complex (MHC) expression on the iPSCs and their derivatives. Compact colonies that expressed pluripotent markers appeared 11 days after viral infection. Embryonic bodies (EB) were produced and differentiated into three germ layers in vitro. Karyotyping and swine leukocyte antigen (SLA) typing showed that the iPSCs were identical to parental somatic cells. Porcine iPSCs expressed only low levels of MHC class I and moderately increased levels on their differentiated derivatives, whereas MHC class II was rarely expressed. In the presence of interferon-gamma (IFN-γ), the expression of MHC class I was elevated on differentiated iPSCs, and gradually decreased after withdrawal of the cytokine. Our data suggest that porcine iPSCs could be useful for preclinical studies of the efficiency and viability of iPSCs, and for devising strategies to rescue transplanted cells from the autologous immune system.  相似文献   
20.
Antibacterial and antifungal activity of pinosylvin, a constituent of pine   总被引:1,自引:0,他引:1  
Lee SK  Lee HJ  Min HY  Park EJ  Lee KM  Ahn YH  Cho YJ  Pyee JH 《Fitoterapia》2005,76(2):258-260
The antibacterial and antifungal activities of pinosylvin (3,5-dihydroxy-trans-stilbene), a constituent of pine, were studied and compared with those of resveratrol (3,5,4'-trihydroxy-trans-stilbene). Pinosylvin exhibited more potent growth inhibitory activity against Candida albicans and Saccharomyces cerevisiae.  相似文献   
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