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431.
Hashimoto M Imamura Y Yasuoka J Kotani S Kusumoto S Suda Y 《Glycoconjugate journal》1999,16(3):213-221
Previously, we showed that quantitatively minor several glycolipids only less than 5% of the lipoteichoic acid (LTA) fraction from Enterococcus hirae ATCC 9790 possessed cytokine-inducing activity, whereas the major component (over 90%) did not [Suda et al. (1995) FEMS Immun Med Microbiol 12:97–112]. The major inactive component was shown to have the chemical structure as was proposed for the LTA by Fischer [Hashimoto et al. (1997) J Biochem 121:779–86], suggesting that so-called LTA is not a cytokine-inducing component in the Gram-positive bacteria. In the present paper, the structure of the hydrophilic part of one of the cytokine-inducing glycolipid tentatively named GL4 is elucidated. GL4 was first subjected to hydrolysis with aqueous HF to give a polysaccharide and a mixture of low molecular weight products. The polysaccharide was composed mainly of highly branching mannan as concluded from NMR and MS analyses of its acetolysis products. The low molecular weight products consisted of phosphate and glycerol, suggesting the presence of a poly(glycerophosphate) structure in the original GL4. From these observations, the hydrophilic part of GL4 was shown to consist of mannose-rich polysaccharide and poly(glycerophosphate), the latter being bound to the former by a phosphodiester linkage. 相似文献
432.
433.
434.
Shozo Takai 《American journal of physical anthropology》1977,47(2):301-304
A hypothesis that the first principal component computed from the covariance matrix of logarithms reflected the specific growth rates of corresponding bones was taken to analyze the growth pattern of the tubular bones of the hand. The total length of 19 tubular bones of the right hand was measured on standardized radiographs of Japanese children (33 boys, 33 girls). Metacarpals in boys and bones of the fifth digit in girls showed higher growth coefficients. The second, third and fourth proximal, and the third and fourth middle phalanges showed lower coefficients for both sexes. These observations suggest the signs of proximal row dominance in boys and of fifth ray dominance in girls in the elongation of the hand bones. A marked sex difference was found in the fifth middle phalanx. In girls the growth coefficients of this bone was much larger than any other bones, but was moderate in boys. 相似文献
435.
Mi Kwon Shozo Fujioka Ji Hyun Jeon Ho Bang Kim Suguru Takatsuto Shigeo Yoshida Chung Sun An Sunghwa Choe 《Journal of Plant Biology》2005,48(2):237-244
Brassinosteroid (BR)-6-oxidases mediate the bridge reactions that connect the late and early C-6 oxidation pathways by converting
6-deoxoBR to 6-oxoBRs. Two similar genes ofArabidopsis, CYP85A1 (At5g38970) andCYP85A2 (At3g30180), are proposed to encode BR-6-oxidases based on findings that heterologously expressed genes mediate BR-6-oxidation
reactions in yeast. However, genetic evidence that both genes are critically involved in the BR-6-oxidation step inArabidopsis has been limited. Here, we show that a double mutant for the two genes displays dwarfism similar to that of typical BR biosynthesis-deficient
mutants, suggesting that they are the major BR-6-oxidases inArabidopsis. Examination of endogenous BR levels and metabolism monitoring tests using this double mutant revealed a great reduction
in the levels of 6-oxoBRs, e.g., TY and CS, due to a lack in the conversion reactions from 6-deoxoCS to CS, and from 6-deoxoTY
to TY. Surprisingly, the double mutant accumulated a significant amount of 6-oxocampestanol, suggesting that the upstream
C-6 oxidation of campestanol to 6-oxocampestanol is not catalyzed by the two BR-6-oxidases inArabidopsis, rather, by another enzyme yet to be discovered. 相似文献
436.
Baudino L Nimmerjahn F Azeredo da Silveira S Martinez-Soria E Saito T Carroll M Ravetch JV Verbeek JS Izui S 《Journal of immunology (Baltimore, Md. : 1950)》2008,180(3):1948-1953
Murine phagocytes express three different activating IgG FcgammaR: FcgammaRI is specific for IgG2a; FcgammaRIII for IgG1, IgG2a, and IgG2b; and FcgammaRIV for IgG2a and IgG2b. Although the role of FcgammaRIII in IgG1 and IgG2a anti-RBC-induced autoimmune hemolytic anemia (AIHA) is well documented, the contribution of FcgammaRI and FcgammaRIV to the development of IgG2a- and IgG2b-induced anemia has not yet been defined. In the present study, using mice deficient in FcgammaRI, FcgammaRIII, and C3, in combination with an FcgammaRIV-blocking mAb, we assessed the respective roles of these three FcgammaR in the development of mild and severe AIHA induced by two different doses (50 and 200 microg) of the IgG2a and IgG2b subclasses of the 34-3C anti-RBC monoclonal autoantibody. We observed that the development of mild anemia induced by a low dose of 34-3C IgG2a autoantibody was highly dependent on FcgammaRIII, while FcgammaRI and FcgammaRIV additionally contributed to the development of severe anemia induced by a high dose of this subclass. In contrast, the development of both mild and severe anemia induced by 34-3C IgG2b was dependent on FcgammaRIII and FcgammaRIV. Our results indicate differential roles of the three activating FcgammaR in IgG2a- and IgG2b-mediated AIHA. 相似文献
437.
Takahashi Y Misumi S Muneoka A Masuyama M Tokado H Fukuzaki K Takamune N Shoji S 《Biochemical and biophysical research communications》2008,368(3):501-507
Humans and some Old World monkeys, chimpanzees, and cynomolgus macaques, are susceptible to oral poliovirus (PV) infection. Interestingly, rhesus macaques, although sensitive to injected PV, are not susceptible to gut infection. Not much is known about the initial event of gut infection by PV in rhesus macaques so far. Here, we show that PV can efficiently enter the lamina propria (LP) by penetrating across intestinal villous M-like cells in rhesus macaques. We found by immunofluorescence analysis that PV effectively invades LP rather than germinal centers (GCs) in rhesus macaques despite expressing PV receptor CD155 on cells within GCs and LP. Furthermore, energy dispersive X-ray spectroscopy demonstrated that gold-labeled PV is spatiotemporally internalized into villous M-like cells and engulfed by macrophage-like cells in LP. These results suggest that rhesus macaques may be resistant to productive gut PV infection owing to a defective translocation of PV to GCs. 相似文献
438.
Party encounter situations were experimentally produced in a group of captive chimpanzees (Pan troglodytes verus) at the Primate Research Institute of Kyoto University, Japan. During weekends all subjects (two adult males and five adult
females) usually stayed together in the rooms (Baseline condition). Under experimental conditions, we shut passages between
rooms to divide the subjects into two groups. We examined the effects of temporal separation of group members on affiliative
interactions, aggressive interactions, and simple proximity. The frequency of affiliative interactions between male and female
chimpanzees and between female chimpanzees increased when they encountered one another after separation, irrespective of male
identity or housing history. Therefore we considered affiliative interactions between males and females during party encounters
as being the response between separated individuals. The same tendency was not found in the frequency of affiliative interactions
between females or between males. Unlike affiliative interactions, neither aggressive interactions nor simple proximity were
influenced by separation. 相似文献
439.
440.
Brassinosteroids regulate grain filling in rice 总被引:10,自引:0,他引:10
Wu CY Trieu A Radhakrishnan P Kwok SF Harris S Zhang K Wang J Wan J Zhai H Takatsuto S Matsumoto S Fujioka S Feldmann KA Pennell RI 《The Plant cell》2008,20(8):2130-2145
Genes controlling hormone levels have been used to increase grain yields in wheat (Triticum aestivum) and rice (Oryza sativa). We created transgenic rice plants expressing maize (Zea mays), rice, or Arabidopsis thaliana genes encoding sterol C-22 hydroxylases that control brassinosteroid (BR) hormone levels using a promoter that is active in only the stems, leaves, and roots. The transgenic plants produced more tillers and more seed than wild-type plants. The seed were heavier as well, especially the seed at the bases of the spikes that fill the least. These phenotypic changes brought about 15 to 44% increases in grain yield per plant relative to wild-type plants in greenhouse and field trials. Expression of the Arabidopsis C-22 hydroxylase in the embryos or endosperms themselves had no apparent effect on seed weight. These results suggested that BRs stimulate the flow of assimilate from the source to the sink. Microarray and photosynthesis analysis of transgenic plants revealed evidence of enhanced CO2 assimilation, enlarged glucose pools in the flag leaves, and increased assimilation of glucose to starch in the seed. These results further suggested that BRs stimulate the flow of assimilate. Plants have not been bred directly for seed filling traits, suggesting that genes that control seed filling could be used to further increase grain yield in crop plants. 相似文献