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211.
The bottlenose dolphin interleukin (IL)-8 cDNA was molecularly cloned. The dolphin IL-8 has an open reading frame of 303-bp encoding 101 amino acids. The homology of the amino acid sequence with that of other species was: sheep, 89.1%; cattle, 88.1%; pig, 85.1%; dog, 85.1%; horse, 79.2%; human, 74.5%; and macaque, 72.3%. The amino acid sequence suggested that dolphin IL-8 was a CXC chemokine. The recombinant dolphin IL-8 protein was recognized with anti-ovine IL-8 monoclonal antibody.  相似文献   
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213.
The major histocompatibility complex (MHC) of cattle is known as the bovine leukocyte antigen (BoLA) and is located on chromosome 23. BoLA has been linked to variation in resistance to disease including bovine leukemia virus‐induced lymphoma and mastitis. Moreover, BoLA appears to influence other traits such as milk yield, growth and reproduction, which are not often measured in humans, and variations in individual immune response to antigen. The BoLA appears to be organized in a similar way to the MHC region in humans, but there are notable differences. A major rearrangement within the class II region has led to the division of the BoLA into two distinct subregions of chromosome 23 separated by about a third of the chromosome’s length. The class IIa subregion contains functionally expressed DR and DQ genes, while the class IIb subregion contains the genes of undefined status such as DYA, DYB, DMA, DMB, DOB, DOA, TAP1, TAP2, LAP2 and LMP7. In addition, one pair of human class II genes (DP) does not appear to have an equivalent in cattle, and there is one pair of DY genes that seem to be found only cattle, sheep and goats. In humans, three classical, polymorphic class I genes (HLA‐A, ‐B and ‐C ) are each present on all haplotypes. However, in cattle, none of the four (or more) classical class‐I genes identified are consistently expressed, and haplotypes differ from one to another in both the gene number and composition. These variations in both class I and II are likely to play an important role in cattle immune responses. This review summarizes current knowledge of the structural and functional features and disease association of BoLA genes.  相似文献   
214.
In order to examine tumor modifying effects of phenolphthalein (PhP), female transgenic mice carrying human prototype c-Ha-ras gene (rasH2 mice) were given a single intraperitoneal injection of 60 mg/kg body weight of N-ethyl-N-nitrosourea (ENU), followed by the diet containing 12,000 ppm PhP for 26-week. Histopathologically, alveolar hyperplasias, adenomas and adenocarcinomas were observed in the ENU + PhP group, but only hyperplasias and adenomas were observed in the ENU alone group. The incidence and multiplicity of adenocarcinomas in the ENU + PhP group was significantly increased as compared to that in the ENU alone group. The combined multiplicity of adenomas and adenocarcinomas in this group was also significantly higher than that of the ENU alone group. In addition, the ratio of area of adenomas in the ENU + PhP group was significantly higher than that in the ENU alone group. The result of our study suggests that PhP has a clear tumor promoting effect in the lung of rasH2 mice.  相似文献   
215.
Although distinct cytokine expression in T cell subsets is well understood in mice and humans, limited information is available on bovine T cell subsets. In the present study, we analyzed the mRNA expression of 10 kinds of cytokines and CD25 expression in CD4+, CD8+, WC1+ and WC1-γδ T cell subsets in bovine peripheral blood by Concanavalin A (Con A) stimulation. CD25 expression was significantly increased in CD4+, CD8+ and WC1+γδ T cells, but not in WC1-γδ T cells by Con A stimulation. In CD4+ T cells, the mRNAs of Interleukin (IL)-2, IL-6, IL-10, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, TNF-β and transforming growth factor (TGF)-β were expressed in control cultures, and IL-3, IL-4 and granulocyte-macrophage colony stimulating factor (GM-CSF) were newly expressed when the cells were stimulated with Con A. CD8+ T cells expressed the mRNAs of IL-6, TNF-α, TNF-β and TGF-β in control cultures, and newly expressed those of IL-2, IFN-γ and GM-CSF, but did not express those of IL-3, IL-4 or IL-10 after Con A stimulation. The cytokine expression profile of WC1+γδ T cells was similar to that of CD8+ T cells. However, WC1-γδ T cells did not express any cytokine mRNA except TGF-â mRNA. These results will contribute to elucidate the participation of T cell subsets in immune responses against infectious disease in cattle.  相似文献   
216.
Hypertrophic cardiomyopathy (HCM) in cats is characterized by concentric left ventricular (LV) hypertrophy and both diastolic and systolic dysfunction. Although impaired cardiac function detected by tissue Doppler imaging (TDI) in cats with HCM was previously reported, reference ranges of TDI in normal cats and cats with HCM have been reported as widely variable. Two-dimensional speckle tracking echocardiography (STE) was useful for assessment of cardiac function in human patients with HCM, but clinical utility was not known in cats. The aim of this study was to assess global and segmental LV myocardial function using STE in cats with HCM whose TDI variables were within the reference range. A total of 35 cats of different breeds were enrolled in this study. The HCM group (n=22) was cats diagnosed as HCM without left atrial enlargement and with normal TDI measurements. HCM cats were further divided into a segmental hypertrophy (S-HCM) group and a diffuse hypertrophy (D-HCM) group. The control group consisted of 13 clinically healthy cats. No cats in any group showed any clinical symptoms. Conventional echocardiography, TDI, and global and segmental STE indices were evaluated and compared between groups. Only the longitudinal strain rate during early diastole was significantly decreased in both HCM groups, even in all segments including those without hypertrophy in S-HCM group. This study suggests that STE parameters are the more sensitive variables compared with conventional TDI parameters to detect early myocardial diastolic dysfunction in cats with HCM.  相似文献   
217.
A two-month-old female Chihuahua was diagnosed as severe pulmonary valvular stenosis (PS). Although balloon valvuloplasty (BV) was successfully performed, restenosis was observed 19 months after the procedure. Euthanasia was chosen due to low output syndrome during the surgical repair attempted when the dog was 5 years old. Postmortem examination revealed markedly thickened pulmonary valve due to the increase of extracellular matrix which might be produced by increased α smooth muscle actin-positive myofibroblasts. The thickening of the valve was associated with restriction of the valve’s motion, resulting in restenosis in the present case. This is the first case report documented histopathological and immunohistochemical findings of the restenotic pulmonary valve in dogs with PS after BV.  相似文献   
218.
Ischemic acute kidney injury (AKI) is the most key pathological event for accelerating progression to chronic kidney disease through vascular endothelial injury or dysfunction. Thus, it is critical to elucidate the molecular mechanism of endothelial protection and regeneration. Emerging evidence indicates that bone marrow-derived cells (BMCs) contribute to tissue reconstitution in several types of organs post-injury, but little is known whether and how BMCs contribute to renal endothelial reconstitution, especially in an early-stage of AKI. Using a mouse model of ischemic AKI, we provide evidence that incorporation of BMCs in vascular components (such as endothelial and smooth muscle cells) becomes evident within four days after renal ischemia and reperfusion, associated with an increase in stromal cell-derived factor-1 (SDF1) in endothelium and that in CXCR4/SDF1-receptor in BMCs. Notably, anti-CXCR4 antibody decreased the numbers of infiltrated BMCs and BMC-derived endothelium-like cells, but not of BMC-derived smooth muscle cell-like cells. These results suggest that reconstitution of renal endothelium post-ischemia partially depends on a paracrine loop of SDF1-CXCR4 between resident endothelium and BMCs. Such a chemokine ligand-receptor system may be attributable for selecting a cellular lineage (s), required for renal vascular protection, repair and homeostasis, even in an earlier phase of AKI.  相似文献   
219.
Diabetic patients need particular care in case of infection, digestive disorder or external injury, because external stress often exasperates the glucose metabolism, which is known as “sick day management”. In addition, severe trauma can be a cause of hyperglycemia with insulin resistance. In spite of critical component of the treatment, the precise mechanisms of how trauma develops posttraumatic diabetes remain unknown. Here, we ablated body wall muscles in Drosophila larvae by laser beam and found that the level of trehalose, the principal sugar circulating in the hemolymph or in the tissues of most insects, was increased. The model may provide a helpful tool to understand the relationship between trauma and sugar metabolism.  相似文献   
220.
The vibrational properties of Japanese bamboo were examined. To obtain the Young’s modulus and shear modulus, a flexural vibration test and a longitudinal vibration test were conducted. The Young’s modulus with vibration in the R-direction was smaller than that measured in the longitudinal vibration test E l . This was due to the shift of the neutral axis to the outer layer. On the other hand, the Young’s modulus with vibration in the T-direction was close to E l . Hence, an adequate Young’s modulus should be used for each use of bamboo. The shear moduli of the LR and LT planes of bamboo were similar to those of beech. There were high correlations between shear moduli of the LR and LT planes and density.  相似文献   
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