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21.
Kobayashi H 《Journal of physiological anthropology》2007,26(2):173-177
Spectral components of heart rate variability (HRV) were repeatedly measured (4-8 measurements; mean: 6 measurements) in 75 healthy Japanese male subjects (age range: 20-61) under two postural conditions (standing and supine). Low-frequency (LF) and high-frequency (HF) components and mean heart rate (HR) were analyzed with special reference to individual variations, which were classified into two types: inter- (interV) and intra-individual variations (intraV). The percent contributions and coefficients of variations were calculated for both interV and intraV. Percent contributions of intraV (intraV%) of HR with standing and supine postures were 15.8 and 12.9%, respectively. The intraV% of HF and LF on standing were 31.5 and 26.5%, while those in the supine posture were 27.8 and 35.5%, respectively. The coefficients of interV (interCV) and intraV (intraCV) were also calculated. The interCVs of HR, HF, and LF on standing were 14.9, 41.4, and 48.4%, while those in the supine posture registered 16.2, 42.9, and 44.2%, respectively. The intraCVs of HR, HF, and LF on standing were 5.0, 19.7, and 21.2%, while those in the supine posture indicated 4.7, 20.1, and 23.0%, respectively. We also calculated the interV and intraV of logarithmic-transformed HRV indexes. The log-transformation remarkably diminished both variables: interCV and intraCV registered 14-16 and 6-7%, respectively. Although interV variations were considerably large, intraV variations of HRV were negligibly small. The HRV indexes decreased with age, although HR remained unchanged. The coefficients of determination (r2) were 14-34%. In the case of log-transformed HRV indexes, the coefficients of determination registered 9-15%, suggesting that 14-34% (raw) or 9-15% (log) of the observed interV may be due to variations in age. 相似文献
22.
We have recently shown that autophagy is induced by ischemia and reperfusion in the mouse heart in vivo. Ischemia stimulates autophagy through an AMP activated protein kinase (AMPK)-dependent mechanism, whereas reperfusion after ischemia stimulates autophagy through a Beclin 1-dependent, but AMPK-independent, mechanism. Autophagy plays distinct roles during ischemia and reperfusion: autophagy may be protective during ischemia, whereas it may be detrimental during reperfusion. We will discuss the role of AMPK in mediating autophagy during myocardial ischemia in vivo. 相似文献
23.
Somatic hypermutation and selection of B cells in thymic germinal centers responding to acetylcholine receptor in myasthenia gravis 总被引:8,自引:0,他引:8
Sims GP Shiono H Willcox N Stott DI 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(4):1935-1944
The muscle weakness in myasthenia gravis (MG) is mediated by autoantibodies against the nicotinic acetylcholine receptor (AChR) at the neuromuscular junction. Production of these pathogenic autoantibodies is believed to be associated with germinal centers (GC) and anti-AChR-secreting plasma cells in the hyperplastic thymus of patients with early onset MG (EOMG). Here, we describe the repertoire of rearranged heavy chain V genes and their clonal origins in GC from a typical EOMG patient. Three hundred fifteen rearranged Ig V(H) genes were amplified, cloned, and sequenced from sections of four thymic GC containing AChR-specific B cells. We found that thymic GC contain a remarkably heterogeneous population of B cells. Both naive and circulating memory B cells undergo Ag-driven clonal proliferation, somatic hypermutation, and selection. Numerous B cell clones were present, with no individual clone dominating the response. Comparisons of B cell clonal sequences from different GC and known anti-AChR Abs from other patients showed convergent mutations in the complementarity determining regions. These results are consistent with AChR driving an ongoing GC response in the thymus of EOMG patients. This is the first detailed analysis of B cell clones in human GC responding to a defined protein Ag, and the response we observed may reflect the effects of chronic stimulation by autoantigen. 相似文献
24.
Mitsuomi?Shimazakimitujin@fish.hokudai.ac.jp; MY myabe@fish.hokudai.ac.jp" title="MS mitujin@fish.hokudai.ac.jp; MY myabe@fish.hokudai.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Hiromitsu?Endo Mamoru?Yabe 《Ichthyological Research》2004,51(2):120-125
Halieutopsis bathyoreos Bradbury, 1988 (Lophiiformes: Ogcocephalidae), previously described only on the basis of the holotype (62.6mm in standard length) from the central North Pacific, is redescribed on the basis of the holotype and six additional specimens (41.2–68.7mm in standard length) collected from the western South Pacific, off Papua New Guinea, and the western North Pacific, including the Japanese Archipelago. Halieutopsis bathyoreos is distinguished from its congeners by having a shelflike rostrum extending anteriorly well beyond the mouth, a dorsal escal lobe slightly bisected ventrally, an illicial cavity square in outline and completely visible in ventral view, and lacking tubercles on the ventral surface of the disk. The following characters are newly added to the diagnoses of this species: rostrum width 21–29% of head length, tubercles on the dorsal surface of the disk about half the diameter of those on the lateral margin, and 13–15 large lateral-line scales on the tail. 相似文献
25.
Kashiwaba M Katsura K Ohnishi M Sasaki M Tanaka H Nishimune Y Kobayashi T Tamura S 《FEBS letters》2003,538(1-3):197-202
In this study we have cloned a novel member of mouse protein phosphatase 2C family, PP2Czeta, which is composed of 507 amino acids and has a unique N-terminal region. The overall similarity of the amino acid sequence between PP2Czeta and PP2Calpha was 22%. On Northern blot analysis PP2Czeta was found to be expressed specifically in the testicular germ cells. PP2Czeta expressed in COS7 cells was able to associate with ubiquitin conjugating enzyme 9 (UBC9) and the association was enhanced by co-expression of small ubiquitin-related modifier-1 (SUMO-1), suggesting that PP2Czeta exhibits its specific role through its SUMO-induced recruitment to UBC9. 相似文献
26.
NF-kappaB promotes breast cancer cell migration and metastasis by inducing the expression of the chemokine receptor CXCR4 总被引:34,自引:0,他引:34
Helbig G Christopherson KW Bhat-Nakshatri P Kumar S Kishimoto H Miller KD Broxmeyer HE Nakshatri H 《The Journal of biological chemistry》2003,278(24):21631-21638
27.
Causal relationship between the loss of RUNX3 expression and gastric cancer 总被引:137,自引:0,他引:137
Li QL Ito K Sakakura C Fukamachi H Inoue Ki Chi XZ Lee KY Nomura S Lee CW Han SB Kim HM Kim WJ Yamamoto H Yamashita N Yano T Ikeda T Itohara S Inazawa J Abe T Hagiwara A Yamagishi H Ooe A Kaneda A Sugimura T Ushijima T Bae SC Ito Y 《Cell》2002,109(1):113-124
Runx3/Pebp2alphaC null mouse gastric mucosa exhibits hyperplasias due to stimulated proliferation and suppressed apoptosis in epithelial cells, and the cells are resistant to growth-inhibitory and apoptosis-inducing action of TGF-beta, indicating that Runx3 is a major growth regulator of gastric epithelial cells. Between 45% and 60% of human gastric cancer cells do not significantly express RUNX3 due to hemizygous deletion and hypermethylation of the RUNX3 promoter region. Tumorigenicity of human gastric cancer cell lines in nude mice was inversely related to their level of RUNX3 expression, and a mutation (R122C) occurring within the conserved Runt domain abolished the tumor-suppressive effect of RUNX3, suggesting that a lack of RUNX3 function is causally related to the genesis and progression of human gastric cancer. 相似文献
28.
In Silene vulgaris (M.) G. cell culture three growth phases were distinguished, namely, a lag phase, an exponential phase and a stationary phase. Pectin termed silenan and an acidic arabinogalactan were isolated as cell wall polysaccharides of S. vulgaris callus at the different growth phases during culture. Production of silenan as the galacturonan (or rhamnogalacturonan) core was observed at the beginning of the exponential phase and at the stationary phase of the callus growth. Arabinogalactan, containing the galacturonic acid residues, is formed at the exponential phase followed by attachment to the core of silenan in the middle of the exponential phase. The arabinogalactan constituent of silenan appeared to be destroyed gradually at the stationary growth phase. The monosaccharide compositions of silenan and arabinogalactan were determined at various phases of the callus growth. Silenan was found to be formed in maximum amounts at the exponential phase of the cell growth. Insignificant alterations of the yields of acidic arabinogalactan were found during culture while total productivity per litre of medium and rate of production per day of arabinogalactan were found to be maximal at the exponential phase of growth. 相似文献
29.
Effects of chemically modified heparin on Chlamydia trachomatis serovar L2 infection of eukaryotic cells in culture 总被引:2,自引:0,他引:2
Yabushita H Noguchi Y Habuchi H Ashikari S Nakabe K Fujita M Noguchi M Esko JD Kimata K 《Glycobiology》2002,12(5):345-351
The mechanism and inhibitors of Chlamydia trachomatis serovar L2 infection of eukaryotic host cells were studied using a tissue culture model infection system. Potent inhibition of infectivity was observed when elementary bodies (EBs) were exposed to heparin or when HeLa 229 cells were treated with heparinase. No significant inhibition was seen the other way around. The same potent inhibition was observed when EBs were exposed to chemically 2-O-desulfated heparin (2-ODS heparin), which is composed of repeating disaccharide units of IdoA-GlcNS(6S), but not when exposed to chemically 6-ODS heparin or completely desulfated and N-resulfated heparin, which is composed of repeating disaccharide units of IdoA(2S)-GlcNS or IdoA-GlcNS, respectively. The inhibitory effects of 2-ODS heparin could be seen only with oligosaccharides longer than dodecasaccharides. The mutant Chinese hamster ovary (CHO) cell line 677, which is deficient in the biosynthesis of heparan sulfate, was less sensitive to C. trachomatis infection than were wild-type CHO cells. F-17 cells, deficient in 2-O-sulfation of heparan sulfate, had the same sensitivity to infection as wild-type CHO cells did. These data suggest that infection of host cells by EBS results from the specific binding of ligand molecules with affinity for heparin on the EB surface to heparan sulfate proteoglycans on the host cell surface. This binding may depend on host cell heparan sulfate chains that are 6-O-sulfated and longer than dodecasaccharides. The 2-ODS heparin oligosaccharides may be a potential agent for the prevention of C. trachomatis infection. 相似文献
30.
A comparison of the plant growth retardant activity of the chlamydocin analogues, compound 1, six derivatives from 1 and 2, and two synthetic analogues revealed that there are two types of retardant in chlamydocin analogues. One, for example in compound 1, requires an oxygen atom at C-8 of the 2-aminodecanoic acid moiety to show retardant activity. The other, for example in compound 8, requires no oxygen atom at C-8 but requires a specific alkyl group chain length for activity. To determine the differences in mode of action of both types of retardant, rice seedlings were separately treated with compounds 1 and 8, and after appearance of dwarfism, their endogenous ABA and GA(1) levels were determined and compared to those of the control. Treatment with 1 (10 nmol/plant) increased ABA levels 4 times higher than that of the control and decreased GA(1) levels to 20% of that of the control. Treatment with 8 (30 nmol/plant) did not affect the ABA level but decreased GA(1) content to 5% of that of the control. 相似文献