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921.
When the diet of sheep is supplemented by the infusion of sulphur-containing amino acids or casein into the abomasum, the newly synthesized wool shows characteristic changes in its amino acid composition, with significant increases in cystine, proline and serine and decreases in aspartic acid and phenylalanine. This modification seems to be due entirely to an alteration in the overall composition of the high-sulphur proteins and to an increase in their proportion in the fibre. These variations are not the result of a change in the composition of individual proteins, but are due to alterations in their relative proportions and to the initiation of the synthesis of `new' proteins, many of which are extremely rich in cystine. It is suggested that the heterogeneity of the high-sulphur proteins may be due, in part, to similar changes in composition caused by natural variations in the nutrition of sheep. 相似文献
922.
Bugarcic A Zhe Y Kerr MC Griffin J Collins BM Teasdale RD 《Traffic (Copenhagen, Denmark)》2011,12(12):1759-1773
The trimeric Vps29-Vps35-Vps26 sub-complex of retromer mediates retrograde transport of transmembrane proteins from endosomes to the trans-Golgi network. Our group has recently identified a Vps26 paralogue, Vps26B, which is able to suppress the expression of Vps26A when exogenously expressed in mammalian cells and defines a distinct retromer complex (Vps26B-retromer) in vivo and in vitro. In this study, we use HEK293 cells stably expressing either Vps26A-myc or Vps26B-myc to address the role of retromer cargo transport and subcellular localization of the two core retromer complexes as defined by the two mammalian-specific Vps26 paralogues. Vps26B-retromer, like Vps26A-retromer, associates with TBC1D5 and GOLPH3. In contrast, no interaction between Vps26B-retromer and cation-independent mannose 6-phosphate receptor (CI-M6PR) was detected, leading to a degradation of this receptor and an increase in cathepsin D secretion. Colocalization of Vps26 paralogues with different endosomally located Rab proteins shows prolonged association of Vps26B-retromer with maturing endosomes relative to Vps26A-retromer. Interestingly, the cycling of CI-M6PR is restored upon deletion of the variable Vps26B C-terminal region indicating that this region is directly responsible for the differential function of the two paralogues. In summary, we show that the two distinct retromer complexes defined by different Vps26 paralogues are not functionally equivalent and that the Vps26B C-terminal region can control cargo selection of the Vps26B-retromer. 相似文献
923.
924.
925.
Toward an Overall Analytical Framework for the Integrated Sustainability Assessment of the Production and Supply of Raw Materials and Primary Energy Carriers 下载免费PDF全文
Jo Dewulf Lucia Mancini Gian Andrea Blengini Serenella Sala Cynthia Latunussa David Pennington 《Journal of Industrial Ecology》2015,19(6):963-977
The sustainable production and supply of raw materials (“nonenergy raw materials”) and primary energy carriers (“energy raw materials”) is a core element of many policies. The natural resource base for their production and supply, and the access thereto, are limited. Moreover, raw material supply is high on environmental and social impact agendas as well. A broad, quantitative framework that supports decision makers is recommended so as to make use of raw materials and primary energy carriers more sustainably. First, this article proposes a holistic classification of raw materials and primary energy carriers. This is an essential prerequisite for developing an integrated sustainability assessment framework (ISAF). Indeed, frequently, only a subset of raw materials and primary energy carriers are considered in terms of their source, sector, or final application. Here, 85 raw materials and 30 primary energy carriers overall are identified and grouped into seven and five subgroups, respectively. Next, this article proposes a quantitative ISAF for the production and supply of raw materials and primary energy carriers, covering all the sustainability pillars. With the goal of comprehensiveness, the proposed ISAF integrates sustainability issues that have been covered and modeled in quite different quantitative frameworks: ecosystem services; classical life cycle assessment (LCA); social LCA; resource criticality assessment; and particular international concerns (e.g., conflict minerals assessment). The resulting four areas of concerns (i.e., environmental, technical, economic, and social/societal) are grouped into ten specific sustainability concerns. Finally, these concerns are quantified through 15 indicators, enabling the quantitative sustainability assessment of the production and supply of raw materials and primary energy carriers. 相似文献
926.
Zhu Yao Akinori Kimura Klaus Hartung Peter J. Haas Andrea Volgger Günter Brünnler Jürgen Bönisch Ekkehard D. Albert 《Immunogenetics》1993,38(6):421-429
We have investigated the DNA polymorphism for the DQA1 promoter region (QAP) and HLA-class II DRB1, DQA1, and DQB1 genes in 178 central European patients with Systemic lupus erythematosus (SLE) using polymerase chain reaction and Dig-ddUTP labeled oligonucleotides. Increased frequencies of DRB1*02 and *03 are confirmed by DNA typing. In addition, the frequencies of DQA1*0501, *0102 and DQB1*0201, *0602 alleles are increased in the patients as compared to controls. The strongest association to SLE is found with DRB1*03 and DQB1*0201 alleles (p<10–7, p corr. <10–5 and p<10–6, p corr. <10–4, respectively). By investigating the DQA1 promoter region in the SLE patients we have detected nine different QAP variants. Increased frequencies of QAP1.2 and QAP4.1 are observed in patients as compared to controls (p <0.05, p corr. = n. s.). Analysis of linkage disquilibria demonstrates a very strong association between QAP variants and DQA1, DRB1 alleles. Certain QAP variants are completely associated with DQA1 and DRB1 alleles, whereas others can combine with different DQA1 and DRB1 alleles. All DRB1*02-positive patients and controls carry QAP1.2, and all DRB1*03-positive patients and controls carry QAP4.1. Conversely, the QAP1.2 variant appears only in DRB1*02 haplotypes, while the QAP4.1 variant can be observed in DRB1*03, *11, and *1303 haplotypes. Based on the strong linkage disequilibria between DRB1-DQA1-DQB1 genes and between DRB1-QAP-DQA1, we have deduced the four-point haplotypes for DRB1-QAP-DQA1-DQB1 in patients and controls. Two haplotypes DRB1*02-QAP1.2-DQA1*0102-DQB1*0602-and DRB1*03-QAP4.1-DQA1*0501-DQB1*0201 are significantly increased in patient as compared to controls (p<0.01, p corr. = n.s., RR = 1.8 and p <10–7, p corr. <10–5, RR = 3.1, respectively). The analysis of relative risks attributed to the various alleles of QAP, DQA1, and DQB1 as well as the investigation of the deduced DRB1-QAP-DQA1-DQB1 haplotypes leads to the conclusion that QAP4.1 and DQA1*0501 on the DR3 haplotypes are probably not involved in SLE susceptibility. There is no evidence for the involvement of DQ2 / dimers coded in transposition. Thus, susceptibility to SLE is on the DR3 haplotype most probably localized at DRB1 or telomeric of DRB1, while for the DR2 haplotype such orientation cannot be given.
SLE study group members: M. Baur, A. Corvetta, H. Ehrfeld, J. Frey, J. R. Kalden, F. Krapf, B. Lang, G. G. Lange, K. Pirner, C. Rittner, E. Röther, P. Schneider, H. P. Seelig, S. Seuchter, W. Stangel, C. Specker, P. Späth, H. Deicher.
Correspondence to: Z. Yao. 相似文献
927.
Adam K. A. Wright Mathieu Bangert Jenna F. Gritzfeld Daniela M. Ferreira Kondwani C. Jambo Angela D. Wright Andrea M. Collins Stephen B. Gordon 《PLoS pathogens》2013,9(3)
Pneumococcal carriage is both immunising and a pre-requisite for mucosal and systemic disease. Murine models of pneumococcal colonisation show that IL-17A-secreting CD4+ T-cells (Th-17 cells) are essential for clearance of pneumococci from the nasopharynx. Pneumococcal-responding IL-17A-secreting CD4+ T-cells have not been described in the adult human lung and it is unknown whether they can be elicited by carriage and protect the lung from pneumococcal infection. We investigated the direct effect of experimental human pneumococcal nasal carriage (EHPC) on the frequency and phenotype of cognate CD4+ T-cells in broncho-alveolar lavage and blood using multi-parameter flow cytometry. We then examined whether they could augment ex vivo alveolar macrophage killing of pneumococci using an in vitro assay. We showed that human pneumococcal carriage leads to a 17.4-fold (p = 0.007) and 8-fold (p = 0.003) increase in the frequency of cognate IL-17A+ CD4+ T-cells in BAL and blood, respectively. The phenotype with the largest proportion were TNF+/IL-17A+ co-producing CD4+ memory T-cells (p<0.01); IFNγ+ CD4+ memory T-cells were not significantly increased following carriage. Pneumococci could stimulate large amounts of IL-17A protein from BAL cells in the absence of carriage but in the presence of cognate CD4+ memory T-cells, IL-17A protein levels were increased by a further 50%. Further to this we then show that alveolar macrophages, which express IL-17A receptors A and C, showed enhanced killing of opsonised pneumococci when stimulated with rhIL-17A (p = 0.013). Killing negatively correlated with RC (r = −0.9, p = 0.017) but not RA expression. We conclude that human pneumococcal carriage can increase the proportion of lung IL-17A-secreting CD4+ memory T-cells that may enhance innate cellular immunity against pathogenic challenge. These pathways may be utilised to enhance vaccine efficacy to protect the lung against pneumonia. 相似文献
928.
Casini A Abbate F Scozzafava A Supuran CT 《Bioorganic & medicinal chemistry letters》2003,13(16):2759-2763
The X-ray crystal structure for the adduct of human carbonic anhydrase II (hCA II) with 4-(4-sulfamoylphenylcarboxamidoethyl)benzenesulfonamide, a topically acting antiglaucoma sulfonamide has been resolved at a resolution of 1.8 A. Its binding to the enzyme is similar with that of other sulfonamides, considering the interactions of the sulfonamide zinc anchoring group, but differs considerably when the organic part of the inhibitor is analyzed. This part of the inhibitor interacts only within the hydrophobic half of the CA active site, leaving the hydrophilic half able to accomodate several water molecules not present in the uncomplexed enzyme. Furthermore, the second head (sulfonamide moiety) participates in two strong hydrogen bonds with amino acid residues (Gly 132 and Gln 136) situated on the rim of the entrance to the active site cleft. Thus, the answer to the question in the title of this paper is that two heads are better than one, since the two sulfamoyl moieties of the inhibitor allow its proper orientation within the active site, with only one head binding in ionized form to the zinc ion, the organic part lying within the hydrophobic half of the active site, and the terminal, carboxamido containing phenylsulfamoyl head participating in strong hydrogen bonds with amino acid residues located at the entrance of it. All these findings are important for the design of better carboxamido CA inhibitors with applications in clinical medicine. 相似文献
929.
Silver KL Conroy AL Leke RG Leke RJ Gwanmesia P Molyneux ME Taylor DW Wallace DT Rogerson SJ Kain KC 《PloS one》2011,6(9):e24985
Placental infections with Plasmodium falciparum are associated with fetal growth restriction resulting in low birth weight (LBW). The mechanisms that mediate these effects have yet to be completely described; however, they are likely to involve inflammatory processes and dysregulation of angiogenesis. Soluble endoglin (sEng), a soluble receptor of transforming growth factor (TGF)-β previously associated with preeclampsia in pregnant women and with severe malaria in children, regulates the immune system and influences angiogenesis. We hypothesized that sEng may play a role in development of LBW associated with placental malaria (PM). Plasma levels of sEng were measured in women (i) followed prospectively throughout pregnancy in Cameroon (n = 52), and (ii) in a case-control study at delivery in Malawi (n = 479). The relationships between sEng levels and gravidity, peripheral and placental parasitemia, gestational age, and adverse outcomes of PM including maternal anemia and LBW were determined. In the longitudinal cohort from Cameroon, 28 of 52 women (54%) experienced at least one malaria infection during pregnancy. In Malawi we enrolled two aparasitemic gravidity-matched controls for every case with PM. sEng levels varied over the course of gestation and were significantly higher in early and late gestation as compared to delivery (P<0.006 and P<0.0001, respectively). Circulating sEng levels were higher in primigravidae than multigravidae from both Cameroon and Malawi, irrespective of malarial infection status (p<0.046 and p<0.001, respectively). Peripheral parasitemia in Cameroonian women and PM in Malawian women were each associated with elevated sEng levels following correction for gestational age and gravidity (p = 0.006 and p = 0.033, respectively). Increased sEng was also associated with the delivery of LBW infants in primigravid Malawian women (p = 0.017); the association was with fetal growth restriction (p = 0.003) but not pre-term delivery (p = 0.286). Increased circulating maternal sEng levels are associated with P. falciparum infection in pregnancy and with fetal growth restriction in primigravidae with PM. 相似文献
930.
Processing of secretogranin II by prohormone convertases: Importance ofPC1 in generation of secretoneurin 总被引:2,自引:0,他引:2
Johannes Hoflehner Ursula Eder Andrea Laslop Nabil G. Seidah Reiner Fischer-Colbrie Hans Winkler 《FEBS letters》1995,360(3):294-298
Secretoneurin is a recently characterized neuropeptidepresent in the primary amino acid sequence of secretogranin II. We investigated the proteolytic processing of secretogranin II by prohormone convertases in vivo in a cellular system using the vaccinia virus system. Both PC1 and PC2 can cleave the secretogranin II precursor at sites of pairs of basic amino acids to yield intermediate-sized fragments. Other convertases like PACE4, PC5 and furin were not active. For the formation of the free neuropeptide secretoneurin a different pattern was found. Only PC1 but none of the other convertases tested including PC2 were capable of generating secretoneurin. Our results demonstrate that the prohormone convertases PC1 and PC2 are involved in proteolytic processing of secretogranin II. The neuropeptide secretoneurin can only be generated by PC1 suggesting tissue-specific processing of secretogranin II in neurons expressing different subsets of the prohormone convertases. 相似文献