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971.
Delphine Benaitreau Esther Dos Santos Marie-Christine Leneveu Philippe De Mazancourt René Pecquery Marie-Noëlle Dieudonné 《Reproductive biology and endocrinology : RB&E》2010,8(1):128
Background
In human pregnancy, a correct placentation depends on trophoblast proliferation, differentiation, migration and invasion. These processes are highly regulated by placental hormones, growth factors and cytokines. Recently, we have shown that adiponectin, an adipokine, has anti-proliferative effects on trophoblastic cells. Here, we complete this study by demonstrating that adiponectin modulates BeWo and human villous cytotrophoblast cell differentiation. 相似文献972.
Intervention with mesenchymal stem cells (MSCs) represents a promising therapeutic tool in treatment-refractory autoimmune
diseases. A new report by Schurgers and colleagues in a previous issue of Arthritis Research & Therapy sheds novel mechanistic insight into the pathways employed by MSCs to suppress T-cell proliferation in vitro, but, at the same time, indicates that MSCs do not influence T-cell reactivity and the disease course in an in vivo arthritis model. Such discrepancies between the in vitro and in vivo effects of potent cellular immune modulators should spark further research and should be interpreted as a sign of caution
for the in vitro design of MSC-derived interventions in the setting of human autoimmune diseases. 相似文献
973.
Qian Ren Ran-Ran ZhangXiao-Fan Zhao Jin-Xing Wang 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2010,151(1):92-98
Thioredoxin (TRX) is involved in cell redox homeostasis. In addition, it is responsible for maintaining proteins in their reduced state. In our study, a Fenneropenaeus chinensis thioredoxin (FcTRX) gene was identified from the Chinese white shrimp. The full length of FcTRX was 777 bp, including a 60 bp 5′ untranslated region (UTR), a 318 bp open reading frame (ORF) encoding a 105 amino acids protein, and a 399 bp 3′ UTR. FcTRX contained a TRX domain with a conserved motif of Cys-Gly-Pro-Cys (CGPC). No signal peptide was predicted by SMART analysis. The molecular mass and pI of FcTRX were 12 kDa and 4.62, respectively. FcTRX is a widely distributed gene, and its mRNA is detected in hemocytes, hearts, hepatopancreas, gills, stomach, and intestine from an unchallenged shrimp. The expression level of FcTRX was the highest in hepatopancreas, where it was down-regulated to the lowest level at 12 h white spot syndrome virus (WSSV) challenge. In the gills, it went up to the highest level at 6 h. Western blot showed that FcTRX protein in hepatopancreas challenged with WSSV was down-regulated from 2 h to 12 h and then restored to the level similar to that of unchallenged shrimp at 24 h. In the gills challenged with WSSV, the FcTRX protein was up-regulated from 6 h to 24 h. Our research indicated its possible role in the anti-WSSV innate immunity of shrimps. 相似文献
974.
Ruhaak LR Hennig R Huhn C Borowiak M Dolhain RJ Deelder AM Rapp E Wuhrer M 《Journal of proteome research》2010,9(12):6655-6664
High-throughput methods for oligosaccharide analysis are required when searching for glycan-based biomarkers. Next to mass spectrometry-based methods, which allow fast and reproducible analysis of such compounds, further separation-based techniques are needed, which allow for quantitative analysis. Here, an optimized sample preparation method for N-glycan-profiling by multiplexed capillary gel electrophoresis with laser-induced fluorescence detection (CGE-LIF) was developed, enabling high-throughput glycosylation analysis. First, glycans are released enzymatically from denatured plasma glycoproteins. Second, glycans are labeled with APTS using 2-picoline borane as a nontoxic and efficient reducing agent. Reaction conditions are optimized for a high labeling efficiency, short handling times, and only limited loss of sialic acids. Third, samples are subjected to hydrophilic interaction chromatography (HILIC) purification at the 96-well plate format. Subsequently, purified APTS-labeled N-glycans are analyzed by CGE-LIF using a 48-capillary DNA sequencer. The method was found to be robust and suitable for high-throughput glycan analysis. Even though the method comprises two overnight incubations, 96 samples can be analyzed with an overall labor allocation time of 2.5 h. The method was applied to serum samples from a pregnant woman, which were sampled during first, second, and third trimesters of pregnancy, as well as 6 weeks, 3 months, and 6 months postpartum. Alterations in the glycosylation patterns were observed with gestation and time after delivery. 相似文献
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979.
A new approach has been developed for the production of enantiomerically pure (S)-β-phenylalanine (S-BPA) and (R)-β-phenylalanine in aqueous medium based on enantioselective acylation and hydrolysis properties of penicillin G acylase
from Escherichia coli. The acylation reaction was highly preferential for the acylation of (R)-BPA to form N-phenylacetyl-(R)-BPA using phenylacetamide as an acyl donor, which was separated and then hydrolyzed to (R)-BPA by the same enzyme at pH 7.5. The optimal acylation reaction was at pH 10, 25°C with a 2:1 molar ratio of phenylacetamide
to BPA, 8 IU ml−1 enzyme and 150 mM BPA. These resulted in a conversion of about 50% BPA; enantiomeric excess of (S)-BPA and (R)-BPA separated were 98 and 99%, respectively. 相似文献
980.
A trypsin inhibitor was isolated from Cassia obtusifolia by ammonium sulfate precipitation, Sepharose 4B-trypsin affinity and Sephadex G-75 chromatography. The inhibitor consisted
of a single polypeptide chain with a molecular mass of 19, 812.55 Da. It was stable from pH 2 to 12 for 24 h, whereas it was
unstable either above 70°C for 10 min or under reduced conditions. The inhibitor, which inhibited trypsin activity with an
apparent Ki of 0.3 μM, had one reactive site involving a lysine residue. The native inhibitor was resistant to pepsin digestion, whereas
the heated inhibitor produced 40% degree of susceptibility. The disulfide linkage and lysine residue were important in maintaining
its conformation. Partial amino acid sequence of the purified protein showed a high degree of homology with various members
of the Kunitz inhibitor family. Moreover, the inhibitor showed significant inhibitory activity against trypsin-like proteases
present in the larval midgut on Pieris rapae and could suppress the growth of larvae. 相似文献