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951.
952.
Y Hayashi S Morikawa M Kawabata Y Hotta 《Biochemical and biophysical research communications》1992,188(1):388-394
It has been shown that heavy metal administration induced the synthesis of cadystins, the small metal chelating peptide with the general structure of (gamma-glu-cys)n-gly, in the fission yeast and in plants. Besides heavy metals, wounds to the cell surface or the incubation with chitosan induced the cadystin synthesis in the fission yeast. Under these induction conditions, the membrane permeability of the fission yeast significantly increased suggesting the structural alteration of the membrane. In these induction, the synthesized cadystins formed complexes with the cellular zinc ions together with or without glutathione. 相似文献
953.
Ho To Akitoyo Hotta Guo Quan Zhang Sa Van Nguyen Motohiko Ogawa Tsuyoshi Yamaguchi Hideto Fukushi Ken-ichi Amano Katsuya Hirai 《Microbiology and immunology》1998,42(2):81-85
Eighteen Coxiella burnetii strains from a variety of clinical and geographical sources were screened for antigenic variation of polypeptides by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) coupled with Coomassie brilliant blue (CBB) staining or immunoblotting. These polypeptide profiles showed the greatest variability in the region from 33 to 8.1 kDa. Such differences in the antigenicity of the polypeptides were also recognized by immunoblotting with 15 various mouse anti-C. burnetii antisera. In addition, we detected a polypeptide at about 28 kDa which was immunodominant in strains from human cases of acute Q fever, milk and ticks but not immunogenic in strains from human cases of chronic Q fever. These findings suggest that this polypeptide is a marker to distinguish between acute and chronic strains. 相似文献
954.
Ferritin, an iron storage protein, has been purified from the last larval hemolymph of Protaetia brevitarsis (coleoptera) by KBr density gradient ultracentrifugation and resource Q (anion exchange chromatography) using fast performance liquid chromatography (FPLC) system. The iron content of ferritin was determined by atomic emission spectroscopy and FereneS stain. Ferritin of P. brevitarsis is shown to have two different subunits presented on a SDSPAGE in normal (N) and ironinjected (I) hemolymph. SDS PAGE revealed that the ferritin consists of two major polypeptides of 27 and 28 kDa in normal hemolymph. Interestingly, however, 30 kDa subunit was substituted for 28 kDa when iron was injected into the hemolymph. Apporximate isoelectric points of 27 kDa, 28 kDa, and 30 kDa ferritin subunits were 6.7, 6.75, and 6.8, respectively. Ferritin of P. brevitarsis was detected by FereneS stain and confirmed by Western blotting using its polyclonal antibody. Other characteristics such as amino acid composition and Nterminal amino acid sequence were investigated. Amino acid composition of ferritin (N and I) was rich in alanine, glycine, glutamine or glutamic acid and serine, but poor in histidine, arginine, methionine and phenylalanine. 相似文献
955.
Takuya Hotta Dai-Hee Kim Motoshi Kamada Nobuharu Fujii Kyung-Min Kim Hideyuki Takahashi 《Biological Sciences in Space》2003,17(3):230-231
Cucumber seedlings display not only gravitropism but also peg formation in response to gravity. Gravimorphogenesis is mediated by auxin distribution. As first step to reveal the mechanism that regulates auxin distribution by auxin efflux, we isolated five partial cDNAs of auxin efflux carriers by RT-PCR method. In addition, we isolated two full-length cDNAs (CsPIN2, CsPIN3) from a cucumber cDNA library. CsPIN2, AtPIN3, AtPIN4 and AtPIN7 fall within the same clade. CsPIN3, AtPIN1 and CsPIN1 fall within the same clade. CsPIN5, CsPIN6 and AtPIN2 fall within the same clade. Our phylogenetic analysis of PIN in cucumber and Arabidopsis indicates that cucumber may diversify CsPIN protein compared with AtPIN protein. 相似文献
956.
A sensitive and precise method for the measurement of peptic activity on protein substrate is described. alpha-Amino residues formed by pepsin digestion are photometrically measured by comparing the absorbances of digested and nondigested material which has been trinitrophenylated. The usual problem of high reagent-blank absorbance is eliminated by using an anion exchange resin, Dowex 1-X8. In contrast to Anson's method, the procedure requires only 1/100 the quantity of protein substrate for analysis. It was proved to be particularly useful for the estimation of initial rates of proteolysis. 相似文献
957.
Biochemical analysis of meiosis in the male mouse 总被引:11,自引:1,他引:10
Spermatogenic cells of the mouse have been separated by gravity sedimentation using a modification of a previously published method. Details are given for the collection of purified samples of specific meiotic stages and for the collection of labelled cell fractions following injection of 3H-thymidine. Suppression of semi-conservative meiotic DNA synthesis, essential to the biochemical analysis of pachytene DNA metabolism, has been achieved by in vivo administration of 1 M hydroxyurea. 相似文献
958.
DEAMINATION OF DEOXYCYTIDINE AND 5-METHYLDEOXYCYTIDINE IN DEVELOPING ANTHERS OF LILIUM LONGIFLORUM (VAR. CROFT) 总被引:3,自引:3,他引:0
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A study has been made of developmental variations in anthers of Lilium longiflorum with respect to the deamination of deoxycytidine and 5-methyldeoxycytidine. Although a periodicity of enzymatic activities surrounding the mitotic cycle has been found, the over-all evidence is against the significance of such periodicity to chromosome duplication. On the basis of evidence obtained a distinction has been drawn between enzyme systems functioning in a broad supporting role and those immediately tied to morphogenetic events. 相似文献
959.
Cardiorespiratory response to low-intensity walking in water and on land in elderly women. 总被引:1,自引:0,他引:1
T Shono K Fujishima N Hotta T Ogaki K Masumoto 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2001,20(5):269-274
The purpose of the present study was to determine whether or not the exercise intensity of water-walking for elderly women could be accurately prescribed by heart rate data obtained during treadmill exercise on land. Six healthy female volunteers, with a mean age of 62.2 +/- 4.2 years, took part in this study. Walking on land was performed on a treadmill. Each subject completed three consecutive 4-minute walks at a progressively increasing velocity (40, 60 and 80 m.min-1), with a 1-minute rest after both the first and second walks. The room temperature and relative humidity were 24.5 +/- 0.2 degrees C and 54.8 +/- 4.0%, respectively. Walking in water was performed in a Flowmill, which is a treadmill positioned at the base of a water flume. Each subject completed three consecutive 4-minute walks at a progressively increasing belt and water-flow velocity (20, 30 and 40 m.min-1), with a 1-minute rest after both the first and second walks. The water depth was at the level of the xiphoid process of each subject. The water temperature was 30.7 +/- 0.1 degrees C. The exercise intensity at the highest workrate was equivalent to 44.2 +/- 10.3% of the heart rate reserve (HRR) during water-walking and 38.4 +/- 4.7% of the HRR during land-walking. There was a highly significant linear relationship between heart rate (HR) and oxygen uptake (VO2) during both water-walking and land-walking. The relationship between HR and VO2 in both exercise modes was similar. Thus, the relationship of HR to VO2 derived from a treadmill-graded walking test on land may be used to prescribe exercise intensity for water-walking in thermoneutral water. 相似文献
960.
Masahiko Takahashi Hiroyuki Nagaretani Tohru Funahashi Hitoshi Nishizawa Norikazu Maeda Ken Kishida Hiroshi Kuriyama Iichiro Shimomura Kazuhisa Maeda Kikuko Hotta Noriyuki Ouchi Shinji Kihara Tadashi Nakamura Shizuya Yamashita Yuji Matsuzawa 《Obesity (Silver Spring, Md.)》2001,9(7):388-393
Objective: Adipocytes secrete various cytokines and matrix proteins. Several of them precipitate in obesity‐associated diseases, including atherosclerosis. In the current study, we have examined the expression of secreted protein, acidic and rich in cysteine (SPARC) in adipose tissue and its significance in obesity and coronary artery disease (CAD). Research Methods and Procedures: The SPARC mRNA expressions both in vivo and in vitro were detected by Northern blot analysis. Plasma SPARC concentrations were measured by enzyme immunosorbent assay. First, we investigated the plasma SPARC levels of 88 unrelated adult Japanese subjects (62 men and 26 women; average age: [± SD] 50 ± 12 years; body mass index [BMI]: 16 to 46 kg/m2). Additionally 31 subjects with CAD diagnosed by coronary angiography (20 men and 11 women) were also investigated. Results: Human adipose tissues expressed abundant SPARC mRNA. SPARC expression in adipose tissues was upregulated in obese db/db mice. Markedly enhanced expression of SPARC mRNA was observed in 3T3‐L1 fibroblasts during adipocyte differentiation. Consistent with these results, plasma SPARC levels proved a positive correlation with BMI in humans (r = 0.27; p < 0.01). Interestingly, plasma SPARC concentrations were significantly elevated in age‐ and BMI‐matched subjects with CAD (p < 0.05). Discussion: SPARC was expressed in adipose tissues and its expression was enhanced in obese mice. In human, plasma SPARC levels were elevated in obesity and CAD patients. This elevated SPARC may be involved in the progression of CAD. 相似文献