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991.
Gilbert Alibert Antoine Carrasco Alain M. Boudet 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1982,721(1):22-29
Vacuoles were isolated from Acer pseudoplatanus cell suspension culture using a one-step procedure involving the lysis of the protoplast plasmalemma through a gradient of Ficoll containing DEAE-Dextran. The vacuole suspensions were slightly contaminated by other organelles (less than 5%) and the isolated vacuoles readily accumulated neutral red. Since α-mannosidase was located exclusively in the vacuoles it was used as a convenient marker. It was shown that the number of vacuoles per protoplast decreased as the cell aged. Studies on the biochemical composition of the isolated vacuoles indicated that amino acids, organic acids and protein contents varied with the cell culture cycle, emphasizing the dynamic status of the vacuolar system in cell suspension cultures of Acer pseudoplatanus. 相似文献
992.
993.
Therapeutic properties of antibodies strongly depend on the composition of their glycans. Most of the currently approved antibodies are produced in mammalian cell lines, which yield mixtures of different glycoforms that are close to those of humans, but not fully identical. Glyco-engineering is being developed as a method to control the composition of carbohydrates and to enhance the pharmacological properties of mAbs. The recent approval in Japan of mogamulizumab (POTELIGEO®), the first glyco-engineered antibody to reach the market, is a landmark in the field of therapeutic antibodies. Mogamulizumab is a humanized mAb derived from Kyowa Hakko Kirin’s POTELLIGENT® technology, which produces antibodies with enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) activity. The approval was granted April 30, 2012 by the Japanese Ministry of Health, Labour and Welfare for patients with relapsed or refractory CCR4-positive adult T-cell leukemia-lymphoma. 相似文献
994.
Benjamin Laenen Aurélie Désamoré Nicolas Devos A. Jonathan Shaw Juana Maria González‐Mancebo Mark A. Carine Alain Vanderpoorten 《Journal of Biogeography》2011,38(4):631-639
Aim Bryophytes exhibit apparently low rates of endemism in Macaronesia and differ from angiosperms in their diversity patterns by the widespread occurrence of endemics within and among archipelagos. This paper investigates the phylogeography of the leafy liverwort Radula lindenbergiana to determine: (1) whether or not morphologically cryptic diversification has occurred in Macaronesia, and (2) the relationships between Macaronesian and continental populations. Location Macaronesia, Europe, Africa. Methods Eighty‐four samples were collected across the species’ distribution range and sequenced at four chloroplast DNA (cpDNA) loci (atpB–rbcL, trnG, trnL and rps4). Phylogenetic reconstructions and Bayesian ancestral area reconstructions were used in combination with population genetics statistics (H, NST, FST) to describe the pattern of present genetic diversity in R. lindenbergiana and infer its biogeographic history. Results Patterns of genetic diversity in R. lindenbergiana exhibit a striking westwards gradient, wherein haplotype (0.90) and nucleotide (0.0038 ± 0.0019) diversity peak in Macaronesia, with a substantial endemic component. We found 20.9% of the genetic variance between biogeographic regions, and most pairwise FST comparisons between regions are significantly different from zero. The global NST (0.78) is significantly higher than the global FST (0.20), providing evidence for the presence of phylogeographic signal in the data. Ancestral area reconstructions suggest that the haplotypes currently found in western Europe share a Macaronesian common ancestor. Main conclusions The haplotype diversification exhibited by R. lindenbergiana in Macaronesia is comparable to that reported for many angiosperm groups at the species level. The apparent lack of radiation among Macaronesian bryophytes may thus reflect the reduced morphology of bryophytes in comparison with angiosperms. The high diversity found among Macaronesian haplotypes, especially in Madeira and the Canary Islands, and the significant NST/FST ratio between Macaronesia and all the other biogeographic regions (an indication that mutation rate exceeds dispersal rates) suggest that Macaronesian archipelagos could have served as a refugium during the Quaternary glaciations. Many haplotypes currently found in Europe share a Macaronesian common ancestor, and this further suggests that Macaronesia might have played a key role in the back‐colonization of the continent. 相似文献
995.
Jean-Gilles Parmentier Bernard Portevin Roy M. Golsteyn Alain Pierré John Hickman Philippe Gloanec Guillaume De Nanteuil 《Bioorganic & medicinal chemistry letters》2009,19(3):841-844
A series of thieno[3,2-b]pyrroloazepinones derivatives related to Hymenialdisine were prepared and tested for CHK1 inhibitory activity. Nanomolar inhibitions were achieved when electron-withdrawing substituents were introduced at position 3 of the thiophene ring. 相似文献
996.
997.
Thomas J. Zupancic Joseph D. Kittle Beth D. Baker Courtney J. Miller Donna T. Palmer Yoko Asai Masayuki Inui Alain Vertès Miki Kobayashi Yasurou Kurusu Hideaki Yukawa 《FEMS microbiology letters》1995,131(2):121-126
Abstract A promoter probe shuttle vector suitable for the isolation of promoter elements from coryneform bacteria was constructed. This vector carried the neomycin phosphotransferase (NPTII) gene from transposon Tn 5 as a reporter gene, and was capable of replication in both Escherichia coli and Brevibacterium flavum . The vector was used in the construction of a B. flavum library of 899 independently isolated promoter clones. Promoters with a wide range of activities in B. flavum , including some very strong promoter elements, were isolated. Comparative analysis suggests that significant differences between B. flavum and E. coli may exist in the determinants of promoter strength. 相似文献
998.
Marie-Odile Parat Marie-Jeanne Richard Marie Th r se Leccia Pierre Amblard Alain Favier Jean Claude B ani 《Free radical research》1995,23(4):339-351
Reactive oxygen species (ROS) are involved in the mechanism of photoaging and carcinogenesis. Skin is endowed with antioxidant enzymes including superoxide dismutases (SOD): cytosolic copper zinc SOD and mitochondrial manganese SOD. The aim of our study was to estimate the protective effect of manganese against oxidative injury on cultured human skin fibroblasts. Dithranol, hydrogen peroxide and UV-A radiation (375 nm) were employed as oxidative stressors. The supply of manganese chloride produced an increase in cellular content of this element up to 24 fold without concomitant elevation of MnSOD activity. Nevertheless, manganese protects cells against two of the three ROS generating systems assessed, namely hydrogen peroxyde and UV-A. This protective effect depends on the concentration of manganese in the medium, 0.1 mM and 0.2 mM protect against UVA cytotoxicity, only 0.2 mM protects against H2O2 cytotoxicity. 相似文献
999.
Olivier Delattre Carlos J. Azambuja Alain Aurias Jessica Zucman Martine Peter Fangrong Zhang Marie Claude Hors-Cayla Guy Rouleau Gilles Thomas 《Genomics》1991,9(4):721-727
The adenylosuccinate lyase (ADSL) which is essential for generating adenylate, maps to the long arm of chromosome 22. By using a Chinese hamster ovary cell line deficient in ADSL activity, we have constructed a set of 17 somatic cell hybrids containing defined regions of human chromosome 22. This panel was extended with six additional hybrids, obtained in other laboratories using various methods of selection. Southern analysis of the hybrids with 38 chromosome 22 probes defined 14 different subregions which could be linearly organized on the long arm of chromosome 22. The order of the probes thus deduced is fully compatible with their previous localization and with the genetic map. The ADSL gene was further sublocalized between the MB and D22S22. This panel, which enables the rapid assignment of chromosome 22 single copy probes to small subregions, will be an important tool in the construction of a detailed physical map of this part of the genome. 相似文献
1000.
Osteopontin (OPN) is now recognized as an important cytokine and extracellular integrin‐binding protein at the crossroads of inflammation and homeostasis. In a previous study, we found that OPN gene (SPP1) polymorphisms are associated with milk performance traits and somatic cell score (SCS), a parameter used to estimate the genetic value of udder health in dairy cattle. In this study, we assessed whether the genetic variations had an impact on SPP1 promoter activity, immune response and the level of OPN secreted into milk. The influence of DNA polymorphisms on the promoter activity of SPP1 was confirmed in vitro. To measure the impact of the genetic variations on OPN secretion into milk, we measured OPN levels in both plasma and milk throughout lactation. Cows were grouped by the OPN haplotypes associated with a high (H2 × H3) or low (H1 × H4) SCS. For both H2 × H3 and H1 × H4, the OPN level in plasma remained low throughout lactation, although the concentration in the milk of H1 × H4 cows increased more in late lactation. Moreover, the macrophages of H1 × H4 cows expressed a lower SPP1 and proinflammatory IL6 in response to infection. Regarding the immune cell response, cows with the genetic potential to secrete higher OPN levels during late lactation had macrophages expressing fewer proinflammatory cytokines, a situation that might explain the genetic association with low somatic cells. Although OPN's favorable roles during late lactation remain to be elucidated, the tissue remodeling properties associated with OPN may be beneficial for reducing the incidence of infection during the transition period in lactating cows. 相似文献