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61.
Leptin, a pleiotropic hormone regulating food intake and energy expenditure, has been shown to directly modulate human polymorphonuclear neutrophil (PMN) functions or indirectly through the action of tumor necrosis factor-alpha (TNF-alpha). Bovine PMN have considerable different characteristics from human PMN. For example, it does not respond to N-formyl-Methionyl-Leucyl-phenylalanine, a well known human PMN activator. In the present study, we tested the effects of leptin and TNF-alpha on superoxide production and degranulation of bovine peripheral PMN, in which both long isoform of leptin receptor (Ob-Rb) and TNF receptor 1 were expressed. Human leptin, human TNF-alpha, phorbol myristate acetate (PMA) and opsonized zymosan particles (OZP) did not stimulate degranulation responses, while zymosan-activated serum (ZAS) did. Neither leptin nor TNF-alpha enhanced the ZAS-induced degranulation responses. TNF-alpha, PMA, OZP and ZAS increased superoxide production in different magnitudes, whereas leptin did not. TNF-alpha, but not leptin, enhanced OZP- and ZAS-induced superoxide production, possibly, in part due to facilitating translocation of p47(phox), a component of NADPH oxidase. These results indicate that, unlike in human PMN, leptin does not have any direct effect on degranulation and superoxide production in bovine PMN, although TNF-alpha influences superoxide production.  相似文献   
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Host sialic acid (SA) has recently been suggested to play an important role in erythrocyte (RBC) infection by Babesia spp. The present study attempted to further determine the specific type of SAs important in the RBC invasion. Bovine RBC was found to bear abundant alpha2-3-linked SA residues but not alpha2-6-linked SA in nature, confirmed by flow cytometric analysis of the neuraminidase (Nm)-treated RBCs. Lectin-blot analyses revealed the removal of alpha2-3-linked SAs from the 97-, 33-, and 31-kDa bands by the Nm treatment. Addition of the Nm-treated RBCs into an in vitro culture of B. bovis resulted in a decreased population of the parasitized RBCs. The thin smear samples from the cultures were then observed under a confocal laser scanning microscope after staining with the alpha2-3-linked SA-specific lectin: a selective invasion of B. bovis was found only in the intact RBCs bearing the SAs, but not in the desialylated RBCs. Furthermore, a significant reduction of the parasitized RBCs was also observed in the culture supplemented with exogenous 3'-sialyllactose containing the alpha2-3-linked SAs. However, the complete inhibition of parasite proliferation was not achieved in the culture. These findings indicate that while the alpha2-3-linked SA-dependent pathway is needed for highly efficient invasion of host RBCs by B. bovis, there might also be other potential alternative pathways.  相似文献   
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We used GIS on a regional scale to estimate and compare supply potentials and costs of small-scale logging systems, a mini-forwarder and a 4-ton truck operated by private logging contractors, and manual logging and a light truck operated by individual forest own- ers, with the mechanized operational system of the Forest Owners' Asso- ciation. Total potential yields of timber and logging residues were esti- mated as 418,895 m3 and 254,962 m3, respectively. The economic bal- ances were estimated and available amounts were projected as supply potentials from profitable sub-compartments. As a result, available amounts of timber and logging residues were estimated at 375,466 m3 (89.9%) and 203,850 m3 (80.0%), respectively. Because their transport expenses were lower than for other systems the most profitable sub-compartments were operated by private logging contractors who sold logging residues at a plant. The profitable sub-compartments operated by individual forest owners were few because the extracting distances were usually greater than 20 m. Raising logging residue prices from 3,000 yen·m-3 to 4,080 yen·m-3 or 6,800 yen·m-3, and establishing forest roads, which reduced some extracting distances to less than 20 m, increased the number and area of profitable sub*compartments, and increased available amounts of logging residues.  相似文献   
66.
Seed dormancy contributes resistance to pre-harvest sprouting.Effects on respective quantitative trait loci (QTLs) for dormancy should be assessed by using fresh seeds before germinability altered through storage.We investigated QTLs related to seed dormancy using backcross inbred lines derived from a cross between Nipponbare and Kasalath.Four putative QTLs for seed dormancy were detected immediately after harvest using composite interval mapping.These putative QTLs were mapped near C1488 on chromosome 3 (qSD-3.1),R2171 on chromosome 6 (qSD-6.1),R1245 on chromosome 7 (qSD-7.1) and C488 on chromosome 10 (qSD-10.1).Kasalath alleles promoted dormancy for qSD-3.1,qSD-6.1 and qSD-7.1,and the respective proportions of phenotypic variation explained by each QTL were 12.9%,9.3% and 8.1%.We evaluated the seed dormancy harvested at different ripening stages during seed development using chromosome segment substitution lines (CSSLs) to confirm gene effects.The germination rates of CSSL27 and CSSL28 substituted with the region including qSD-6.1 were significantly lower than those of Nipponbare and other CSSLs at the late ripening stage.Therefore,qSD-6.1 is considered the most effective novel QTL for pre-harvest sprouting resistance among the QTLs detected in this study.  相似文献   
67.
Hepatocyte growth factor/scatter factor (HGF/SF) is a pleiotropic cytokine that plays a crucial role in the embryonic and postnatal development of various organs including the mammary gland. We cloned bovine HGF and its c-Met receptor cDNAs, and examined their expression during mammary gland development in dairy cows. The 2.5-kbp HGF cDNA clone contained a 2190 bp open reading frame coding a 730 amino acid protein, while the 4.8-kbp c-Met cDNA clone contained a 4152 bp open reading frame coding a 1384 amino acid protein. The bovine HGF and c-Met sequences exhibited more than 87% identity with those of other mammals. RT-PCR analysis revealed ubiquitous expression of both HGF and c-Met mRNAs in various bovine tissues tested. HGF mRNA was detected only in the inactive stage of bovine mammary gland development and not in the developing, lactating, and involuting stages, while c-Met mRNA was detected in the inactive and involuting stages. Immunohistochemical analysis demonstrated that the c-Met protein was found on mammary epithelial cells in the inactive, developing, and involuting stages, and on myoepithelial cells in all stages. These results suggest pivotal roles of HGF and c-Met in the development of bovine mammary gland.  相似文献   
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We determined the complete nucleotide sequence of the mitochondrial genome of the semidomestic red deer (Cervus elaphus) of New Zealand. The genome was 16 357 bp long and contained 13 protein‐coding genes, 12SrRNA, 16SrRNA, 22 tRNAs and a D‐loop as found in other mammals. Database homology searches showed that the mitochondrial DNA (mtDNA) sequence from the New Zealand semidomestic deer was similar to partial mtDNA sequences from the European, Norwegian (C. e. atlanticus) and Spanish red deer (C. e. hispanicus). Phylogenetic analysis of the mitochondrial protein‐coding regions revealed two well‐defined monophyletic clades in subfamilies Cervinae and Muntiacinae. However, red deer and Sika deer were not found to be close relatives. The analysis did identify the red deer as a sister taxon of a Samber/Sika deer clade, although it was more closely related to the Samber than the Sika group.  相似文献   
70.
We previously identified a novel gonad-specific expression gene (Gse) and investigated its expression during gametogenesis in the mouse testis and ovary. In this study, we generated a polyclonal antibody to GSE protein and determined the profiles of the protein's expression in germ cells and preimplantation embryos in detail using immunocytochemical and immunofluorescence staining. In a Western blot analysis, the anti-GSE antibody recognized long and short isoforms (approximately 27.6 kDa and 23.1 kDa) of the protein in the mouse testis and the long isoform in the ovary. In the mouse testis, GSE protein was expressed in spermatocytes I in the pachytene stage, round spermatids, and elongated spermatids. In the mouse ovary, the protein was located in the cytoplasm and nucleus of all oocytes regardless of the stage of the ovarian follicles. In preimplantation embryos from the pronuclear to blastocyst stage, however, GSE protein was mainly detected in the nuclei of cells. At the blastocyst stage, the protein was confirmed to have accumulated in the inner cell mass (ICM), whereas it had mostly disappeared from the trophectoderm (TE). These findings suggest that GSE protein may play a role in the establishment of nuclear totipotency and may be associated with early lineage specification.  相似文献   
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