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31.
To determine the independent decomposition rates of lignin and cellulose of decayed woody debris, a technique for the rapid analysis of lignin and cellulose is required. We applied a near-infrared spectroscopy (NIRS) technique to measure the lignin and holocellulose content in decayed wood. We succeeded in creating partial least-squares (PLS) models to estimate the lignin and holocellulose content in the decayed wood of five species using NIR spectra. Although the accuracy was acceptable for the estimation of a five-species mixed model (R 2 = 0.970 for lignin and R 2 = 0.962 for holocellulose), it was further improved when the model was applied to each species independently. This combination of NIRS and a PLS model is a valuable tool for the determination of the lignin and holocellulose content in decayed wood. The technique is time efficient (3 min per sample) and non-hazardous (no acid treatment is required).  相似文献   
32.
A subcutaneous mass was found in the lower ventral neck region of a 55-week-old male Mongolian gerbil (Meriones unguiculatus). Histopathologically, the mass involved salivary glands and featured diffuse proliferation of pleomorphic neoplastic cells with large necrotic foci. The lesion was well demarcated from the surrounding tissue, although invasive growth to fibrous septa was occasionally observed. The neoplastic cells were mainly arranged in irregular sheets with severe cellular atypia, round to oval nuclei and varying amounts of eosinophilic cytoplasm. Mitotic figures and multinucleated giant cells were frequent. Immunohistochemical analysis revealed that the neoplastic cells were strongly positive for vimentin and S-100 and negative for NSE, cytokeratin, α-SMA, c-kit, factor VIII, CD34, α-1-antitrypsin, lysozyme and MSR-A. Based on the results, the mass was diagnosed as an undifferentiated sarcoma of the salivary gland. To the best of our knowledge, this is the first report of such a tumor in Mongolian gerbils.  相似文献   
33.
In our previous study (Kawashima et al., Biol Reprod 2009; 80: 1293-1304), we suggested that the first cycle of spermatogenesis recovered from busulfan-induced temporary arrest was a good model system to analyze the proteins expressed at the specific stages of spermatogenesis in the mouse, and this has been confirmed in the present paper. Namely, six-week-old mice were injected with busulfan at 20 mg/kg body weight. The germ cells except for the undifferentiated spermatogonia disappeared by 32 days after injection. The surviving spermatogonia started to proliferate, and spermatogenesis was entirely recovered about 77 days after injection. By proteome analysis of the busulfan-treated testis during the process of recovery of spermatogenesis, we identified a protein that was expected to be expressed in the spermatogenic cells as Superkiller viralicidic activity-2-like-2 (SKIV2L2). Skiv2l2 mRNA was found in the kidney, epididymis and heart as well as the testis. In the testis, Skiv2l2 mRNA was shown to be highly expressed in the spermatocytes at stages I to VI. On the other hand, SKIV2L2 protein was found to be predominantly localized in the nuclei of round spermatids. In accordance with the fact that SKIV2L2 belongs to the Ski2 family within the superfamily 2 of RNA helicases, it has been shown that SKIV2L2 has both the RNA-binding and ATPase activities.  相似文献   
34.
The rDNA PCR–RFLP of foxtail millet (Setaria italica) germ-plasm collected throughout Eurasia and from a part of Africa was investigated with five restriction enzymes according to our previous study. Foxtail millet germ-plasms were classified by length of the rDNA IGS and RFLP; clear geographical differentiation was observed between East Asia, the Nansei Islands of Japan-Taiwan-the Philippines area, South Asia and Afghanistan-Pakistan. We also found evidence of migration of foxtail millet landraces between the areas. We calculated diversity index (D) for each region and found that center of diversity of this millet is East Asia such as China, Korea and Japan.  相似文献   
35.
ABSTRACT:   Elution and internal migration of free amino acids (FAA) in fish meats by soaking were investigated when the meat strips were soaked in various concentrations of sodium chloride (NaCl) or sorbitol solution. Rapid decrease of FAA in an earlier phase of soaking was followed by a mild one, irrespective of the kind and the concentration of soaking solution. The loss of FAA by soaking in NaCl solution was slightly larger than that in sorbitol solution. However, regardless of the kinds of soaking solution, the elution of FAA from fish meats by soaking was only dependent on the soaking time, independently of the concentration, namely osmotic pressure of the soaking solution. Conversely, sluggish migration of FAA from the inside to the surface of the meat strips proceeded by soaking. These results suggested that the elution of FAA from fish meats by soaking was driven by a simple diffusion from the surface of the meats to soaking solution, but it was regulated by sluggish migration rate of FAA in fish meats.  相似文献   
36.
Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation and migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. Recently, frequent mutations of the LPA receptor-1 (LPA1) gene were detected in rat lung adenocarcinomas induced by N-nitrosobis(2-hydroxypropyl)amine (BHP). In this study, to evaluate the involvement of other LPA receptor gene alterations during lung carcinogenesis, we investigated mutations of the LPA2, LPA3, LPA4 and LPA5 genes in lung adenocarcinomas induced by BHP in rats. Fifteen male Wistar rats, 6 weeks of age, were given 2000 ppm BHP in their drinking water for 12 weeks and then maintained without further treatment until sacrifice at 25 weeks, and 15 adenocarcinomas were obtained. Genomic DNAs were extracted from frozen tissues, and the LPA2, LPA3, LPA4 and LPA5 genes were examined for mutations, using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. No mutations of LPA2, LPA3, LPA4 and LPA5 were detected in the 15 adenocarcinomas. These results suggest that alterations due to LPA2, LPA3, LPA4 and LPA5 gene mutations might not be involved in the development of lung adenocarcinomas induced by BHP in rats.  相似文献   
37.
A 13-year-old, female, mixed-breed dog with a huge cranial mediastinal mass underwent radiotherapy (RT). On the following day, the dog presented with lethargy and anorexia. Hematological examination revealed elevated levels of blood urea nitrogen, creatinine, inorganic phosphorus, potassium, lactate dehydrogenase, creatine phosphokinase and aspartate aminotransferase, decreased calcium level, and metabolic acidosis. Urine output markedly decreased. The patient recovered with fluid therapy and diuretic therapy; however, died suddenly from an unknown cause 11 days after RT completion. Histopathological examination after necropsy showed thymoma in the cranial mediastinum and extensive tubular necrosis of both kidneys which may be due to RT-induced tumor lysis syndrome (TLS). This report suggests that the risk of TLS should be evaluated in dogs with thymoma who undergo RT.  相似文献   
38.
Appressorium differentiation, one of the most important steps in pathogenesis by the rice blast fungus, Pyricularia oryzae, is strongly coordinated with the cell cycle. In this study, we identified an ortholog gene of 53BP1, which encodes a signal transducer protein that participates in G2-M cell cycle checkpoint in higher eukaryotes, in the genome of P. oryzae and characterized the phenotype of deletion and overexpression mutants. Deletion mutants showed no significant deficiency in vegetative growth compared to wild-type and complemented strains, even on the media containing DNA-damaging agents. However, these null mutants had abnormal appressoria and formed more appressoria per conidium than in the wild type and were unable to penetrate the epidermis of rice leaves. eGFP-fused Mop53BP1 and qRT-PCR analyses revealed that Mop53BP1 is expressed during the first hours of appressorium formation. In addition, in overexpression mutants, Mop53BP1 localized to nuclei during all stages of appressorium maturation and penetration, and the mutants were resistant to the microtubule inhibitor benomyl, suggesting that Mop53BP1 is nuclear protein and may have some role related to microtubules.  相似文献   
39.
Rhodococcus equi was isolated from fecal and soil samples from four native Jeju horse farms and six Thoroughbred farms in Jeju, Korea. The isolates were examined for the presence of virulence-associated 15-17-kDa antigens (VapA) by colony blotting, using the monoclonal antibody 10G5, and for the gene encoding VapA by PCR. R. equi was isolated from all 36 soil samples collected from the 10 farms with between 5.0 x 10(2) and 7.5 x 10(4) colony-forming units (cfu) per gram of soil, and from 37 of 40 fecal samples with between 5.0 x 10(1) and 1.1 x 10 (5) cfu per gram of feces. Virulent R. equi was isolated from seven farms and appeared in 2.0% of isolates (10 of 508). Of the 10 virulent isolates, four contained a 90-kb type II plasmid, which has been found in isolates from the Kiso native horses of Japan, and the other six contained a new variant, which did not display the EcoRI and EcoT22I digestion patterns of the 10 representative plasmids already reported (85-kb types I, II, III, and IV; 87-kb types I and II; 90-kb types I, II, III, and IV). We designated the new variant as the "90-kb type V" plasmid, because its EcoRI digestion pattern is similar to that of the 90-kb type II plasmid. This is the first report of the prevalence of virulent R. equi in Jeju, Korea. The same virulence plasmid type is found in both Korean and Japanese isolates, providing insight into the origin, ancestry, and dispersal of native horses in Korea and Japan.  相似文献   
40.
Estrogen (E) exerts its function by binding to two intracellular estrogen receptors, ERalpha and ERbeta. Although ERs have been reported to be expressed in the bovine corpus luteum (CL), the mechanisms that control ER expression in the bovine CL are not fully understood. To determine the possible regulatory mechanisms of ERalpha and ERbeta that meditate distinct E functions, we examined 1) the changes in the protein expressions of ERs in the CL throughout the luteal phase and 2) the effects of prostaglandin (PG) F2alpha, tumor necrosis factor-alpha (TNFalpha) and interferon-gamma (IFNgamma) on the expressions of ERs in cultured bovine luteal cells. Western blot analyses revealed that ERalpha and ERbeta proteins were expressed throughout the luteal phase. The ERalpha protein level was high at the early luteal (Days 2-3 after ovulation) and mid-luteal stages (Days 8-12) and was extremely low at the regressed luteal stage (Days 19-21). The ERbeta protein level increased from the early to developing luteal stage, remained at the same level at the mid-luteal stage and decreased thereafter. The ratio of ERbeta to ERalpha was higher in the regressed stage than in the other stages. Luteal cells obtained from mid-stage CLs (Days 8-12) were incubated with PGF2alpha (0.01-1 microM), TNFalpha (0.0145-1.45 nM) or IFNgamma (0.0125-1.25 nM) for 24 h. PGF2alpha and TNFalpha inhibited ERa and ERbeta mRNA expressions. IFNgamma suppressed ERbeta mRNA expression but did not affect the expression of ERalpha mRNA. However, the ERalpha and ERbeta protein levels were not affected by any of the above treatments. These data indicate that PGF2alpha, TNFalpha and IFNgamma regulate ERalpha and ERbeta mRNA expressions in bovine luteal cells. Moreover, the changes in the ERbeta/ERalpha ratio throughout the luteal phase suggest that ERalpha is associated with luteal maintenance. Therefore, a dramatic decrease in ERalpha at the regressed luteal stage could result in progression of structural luteolysis in the bovine CL.  相似文献   
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