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61.
Phylogeographic characteristics and population structure of Japanese wild boar (Sus scrofa leucomystax) were investigated using mitochondrial DNA (mtDNA) sequence data. Sixteen Japanese wild boar haplotypes detected from partial sequences of the mtDNA control region (574-bp) from 180 Japanese wild boar specimens from 10 local populations on Honshu, Shikoku, and Kyushu islands and 41 haplotypes from other S. scrofa were analyzed using the neighbor-joining method. The Japanese wild boars were more closely related to Northeast Asian wild boars from Mongolia than to the other Asian continental S. scrofa. The Japanese and Northeast Asian wild boars were not significantly distinguished by corrected average pairwise difference analysis. The ancestors of Japanese wild boars are suggested to have been part of the continental S. scrofa population that spread from Southeast to Northeast Asia during the Middle to Late Pleistocene. The Japanese wild boar mtDNA haplotype cladogram shows 95% parsimoniously plausible branch connections supporting three sympatric clades. Nested clade analysis indicates that these three clades are the result of distinct historical events or gene flow. The present population of Japanese wild boars may have been formed by a few independent migrations of distinct clades from the continent with subsequent mixing on the Japanese Islands. 相似文献
62.
Mori S Shinohata R Renbutsu M Takahashi HK Fang YI Yamaoka K Okamoto M Yamamoto I Nishibori M 《Cell and tissue research》2003,312(3):353-359
Vascular smooth muscle cell (SMC) hyperplasia is known to be an important component in the pathogenesis of arteriosclerosis and restenosis. Although heparin has been well recognized as the representative molecule suppressing SMC growth in vitro, attempts to use heparin as a therapeutic anti-restenosis drug have not favorably influenced the angiographic or clinical outcome after angioplasty in some clinical trials. In this study, we have examined the effect of histidine-rich glycoprotein (HRG), a relatively abundant serum glycoprotein (~100 micrograms/ml in human serum), on the growth inhibition of cultured vascular SMC by heparin. Vascular SMC growth was significantly inhibited by heparin, giving nearly 85% inhibition with 100 micrograms/ml heparin. HRG reversed heparin-induced SMC growth inhibition in a dose dependent manner; 75% restoration of cell growth was observed when 100 micrograms/ml of HRG was co-added with 100 micrograms/ml heparin. Interestingly, micromolar concentrations of the zinc ion (0-10 microM), compatible with concentrations released from activated platelets, were found to enhance the restorative action of HRG. Western blot experiment demonstrated no significant amounts of the HRG moiety in fetal bovine serum, eliminating the possible contribution of contaminant HRG from culture media. These findings indicate that HRG, in combination with the zinc ion, plays a role in modulating the SMC growth response in pathophysiological states and explain the lack of success of heparin as a therapeutic anti-restenosis drug in clinical trials. 相似文献
63.
Kanamasa S Yamaoka K Kawaguchi T Sumitani J Arai M 《Bioscience, biotechnology, and biochemistry》2003,67(12):2661-2663
Transformation systems for Aspergillus aculeatus has been developed, based on the use of the pyrithiamine resistance gene of Aspergillus oryzae and the orotidine-5'-monophosphate decarboxylase gene (pyrG) of Aspergillus nidulans. An A. aculeatus mutant which can be transformed effectively by the A. nidulans pyrG gene was isolated as a transformation host. This is the first report of transformation of A. aculeatus. 相似文献
64.
OBJECTIVE: Gynecomastia is known to be a side effect of neuroleptics. The authors investigated the prevalence of gynecomastia and galactorrhea in a group of regularly neuroleptic-treated male patients. METHODS: Gynecomastia was defined as a palpable, discrete button of firm subareolar tissue measuring at least 2 cm in diameter. The subjects were 100 male patients who were taking neuroleptic treatment regularly. Each patient gave informed consent for the research involved in this study. RESULTS: (1) Palpable gynecomastia was present in 2% of the patient group, but not at all in the normal group. (2) Galactorrhea was not present in either patient or normal group. (3) The mean level of the serum prolactin in the group of patients without gynecomastia (n = 53) was significantly higher than that in the normal group (n = 35), but there was no significant difference in blood luteinizing hormone, follicle-stimulating hormone, testosterone (T), estradiol (E(2)) or T/E(2) ratio between the groups. (4) The mean level of the T/E(2) ratio in the patients with gynecomastia tended to be higher than that in the group of patients without gynecomastia. CONCLUSIONS: Overall, these results seem to indicate that (i) gynecomastia is not common in the Japanese population, and (ii) in male patients neither palpable gynecomastia nor galactorrhea is a common side effect of neuroleptics. To clarify the relation between gynecomastia and neuroleptic treatment, large prospective studies are required. 相似文献
65.
The expression of adhesion molecules on the lymphatic endothelium of human small intestine and submandibular lymph node was studied immunohistochemically with the antibodies for selectin family and Ig superfamily members. In both small intestine and submandibular lymph node, lymphatic endothelium did not express intercellular adhesion molecule-1 and endothelial cell-selectin but expressed platelet-endothelial cell adhesion molecule-1 (PECAM-1). Though lymphatic vessels may not have a positive function in leukocyte rolling and adhesion, lymphatic endothelium may interact with leukocytes, with PECAM-1 playing a role. 相似文献
66.
67.
A H Chuang M R Waterman K Yamaoka L Cottam 《Archives of biochemistry and biophysics》1975,167(1):145-150
Measurement of the transverse water proton relaxation rate has been used to study the effect of pH, carbamylation, and other hemoglobins on the aggregation of deoxyhemoglobin S inside intact erythrocytes. Upon complete deoxygenation, cyanate-treated () erythrocytes and erythrocytes heterozygous with respect to hemoglobin S (, , and ) have high transverse water proton relaxation rates very similar to the values obtained with homozygous () erythrocytes. These results suggest extensive intermolecular interactions between deoxyhemoglobin S molecules and a resultant increase in the correlation time for the small fraction of “irrotationally bound” water. When the transverse relaxation rate in deoxygenated () erythrocytes was measured as a function of pH, the maximum rate was observed between pH 7.0 and 7.5. Upon increasing the pH beyond this range the observed relaxation rate decreases as does the number of sickled cells. Upon decreasing the pH, the observed transverse relaxation rate also decreases but the ratio of values from () erythrocytes remains in the normal range of 4–6 and the number of sickled cells does not change. Therefore, the deoxyhemoglobin S aggregate inside sickled erythrocytes, as observed by water proton relaxation rates, is not altered by carbamylation or by the presence of nongelling hemoglobins. In addition, the enhancement of the relaxation rates as a function of pH is consistent with the number of sickled forms observed. 相似文献
68.
Yamaoka A Ozawa Y Ueno Y Endo T Morimoto Y Urushiyama A Ohmori D Imai T 《FEBS letters》2011,585(9):1299-1302
Cyanidioschyzon merolae (Cm) is a single-cell red alga that grows under moderately thermophilic (40-50°C), acidic (pH 1-3) conditions. We purified a Cm ferredoxin (Fd) that was characterized as a plant-type [2Fe-2S] Fd by physicochemical techniques. X-ray crystallography revealed that the overall three-dimensional structure of CmFd was highly similar to, but slightly different from, the [2Fe-2S] Fd from Spinacia oleracea, whose growth temperature is 15-20°C. Therefore, slight structural differences, including non-covalent-bond number and amino acid sequence, may underlie the differential thermostabilities of the plant-type Fds. 相似文献
69.
Matsunaga N Kaku T Itoh F Tanaka T Hara T Miki H Iwasaki M Aono T Yamaoka M Kusaka M Tasaka A 《Bioorganic & medicinal chemistry》2004,12(9):2251-2273
Novel nonsteroidal C(17,20)-lyase inhibitors were synthesized using de novo design based on its substrate, 17 alpha-hydroxypregnenolone, and several compounds exhibited potent C(17,20)-lyase inhibition. However, in vivo activities were found to be short-lasting, and in order to improve the duration of action, a series of benzothiophene derivatives were evaluated. As a result, compounds 9h, (S)-9i, and 9k with nanomolar enzyme inhibition (IC(50)=4-9 nM) and 9e (IC(50)=27 nM) were identified to have powerful in vivo efficacy with extended duration of action. The key structural determinants for the in vivo efficacy were demonstrated to be the 5-fluoro group on the benzothiophene ring and the 4-imidazolyl moiety. Superimposition of 9k and 17 alpha-hydroxypregnenolone demonstrated their structural similarity and enabled rationalization of the pharmacological results. In addition, selected compounds were also identified to be potent inhibitors of human enzyme with IC(50) values of 20-30 nM. 相似文献
70.
Noriyuki Koibuchi Ryuichi Konno Shigeru Matsuzaki Hideki Ohtake Akira Niwa Sadao Yamaoka 《Histochemistry and cell biology》1995,104(5):349-355
d-Amino acid oxidase (DAO), which catalyzes oxidative deamination ofd-amino acids, is known to be highly expressed in the kidney. This study was designed to examine the localization of DAO mRNA in the mouse kidney using in situ hybridization histochemistry (ISH). For comparison, ISH for mRNA of ornithine decarboxylase (ODC), which is also highly expressed in the mouse kidney, was simultaneously performed. Adult, male mice which received 1 mg of testosterone propionate or vehicle injection, were sacrificed 14 h after injection and their kidneys were removed and processed for ISH. Hybridization signals for both mRNAs were exclusively located over the epithelial cells of the proximal tubule in the vehicle-treated animals. Signals for the DAO mRNA were observed at nearly the same hybridization intensity throughout the proximal tubule, whereas hybridization signals for the ODC mRNA were observed exclusively in the pars convoluta. Following testosterone treatment, ODC mRNA in the pars convoluta was expressed with a stronger intensity than that in the vehicle-injected animals. ODC mRNA was also expressed in the pars recta with a weaker intensity than in the pars convoluta. On the other hand, DAO mRNA expression was little affected by testosterone treatment. These results indicate that, although both genes are possibly expressed in the same cells, the expression of these genes is regulated by different mechanisms. 相似文献