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21.
Jintang Sun Meixiang Yang Yanli Ban Wenjuan Gao Bingfeng Song Yang Wang Yun Zhang Qianqian Shao Beihua Kong Xun Qu 《PloS one》2016,11(1)
NK cells accumulate at the maternal-fetal interface (MFI) and play essential roles in maintaining immune tolerance during pregnancy. The mechanisms that facilitate NK cells tolerance to fetal tissue are largely unknown. T cell Ig and mucin domain-containing protein 3 (Tim-3) is a newly defined molecule with essential immunological function in many physiological and pathological processes. Recent study showed that Tim-3 was involved in the regulation of immune tolerance at MFI. However, whether Tim-3 regulates NK cells cytotoxicity toward trophoblasts is unclear. Here, we showed Tim-3 was mainly expressed by decidual NK cells (dNK) and Tim-3 level in dNK was higher than peripheral NK cells (pNK). Tim-3+ dNK expressed more levels of mature markers CD94 and CD69 than Tim-3- dNK cells and blocking Tim-3 significantly inhibited dNK IFN-γ and TNF-α secretion. Furthermore, we found TGF-β1 may contribute to such up-regulation of Tim-3 in NK cells. Interestingly, blocking Tim-3 enhanced NK cytotoxicity toward trophoblast cell line HTR-8 but not K562. We found HTR-8 expressed Tim-3 ligand Galectin-9, in contrast K562 did not. Small interfering RNA-mediated silencing of Galectin-9 expression enhanced NK cytotoxicity toward HTR-8. We further showed Tim-3/Galecin-9 inhibited NK cytotoxicity toward trophoblast partially via impairing the degranulation process. In addition, clinical data showed that abnormal Tim-3 level on pNK might be associated with recurrent spontaneous abortion (RSA). Thus, our data demonstrate Tim-3/Galectin-9 pathway maintains local tolerance by suppressing NK cytotoxicity toward trophoblasts which may represent a new immunologic tolerance mechanism at MFI. 相似文献
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目的: 在Bacillus subtilis中表达异源D-海因酶基因(hyd)和D-氨甲酰水解酶基因(adc),构建重组细胞作为催化剂,用于生产D-对羟基苯甘氨酸(D-HPG)。方法: 构建hyd表达质粒,考察培养基中二价金属离子对D-海因酶活性的影响。过表达acoR基因,考察AcoR蛋白胞内水平与PacoA-hyd基因拷贝数的关系。筛选表达adc基因的启动子,构建hyd和adc基因共表达质粒,考察双酶活性菌株的催化特性。结果: 成功构建了海因酶表达质粒pHPS和pUBS,培养基中添加0.8mmol/L的MnCl2·4H2O,使168N/pUBS菌株的D-海因酶活性达到956U/gDCW。整合表达Pcdd-acoR基因,使LSL02/pUBS菌株的D-海因酶活性达到1 470U/gDCW。单拷贝PAE-adc基因的表达水平相对最高。双酶共表达质粒pUBSC被成功构建,菌株LSL02/pUBSC的最适催化温度为40℃45℃,催化活性能够持续12h,当底物起始浓度为20g/L时,反应12h生成的D-HPG达到14.32g/L,转化率达到95%,收率超过80%。结论: 构建具有D-海因酶和D-氨甲酰水解酶双酶活性的重组Bacillus subtilis作为全细胞催化剂,用于海因酶法生产D-HPG,具有技术上的可行性和优势。 相似文献
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Pyrolysis mass spectrometry (PyMS) is a rapid, simple, high-resolution analytical method based on thermal degradation of complex
material in a vacuum, and has been widely applied to the discrimination of closely related microbial strains. Minimally prepared
samples of embryogenic and non-embryogenic calluses derived from various higher plants (sweet potato, morning glory, Korean
ginseng, Siberian ginseng, and balloon flower) were subjected to PyMS for spectral fingerprinting. A dendrogram based on the
unweighted pair group method, with arithmetic mean of pyrolysis mass spectra, divided the calluses into Siberian ginseng embryogenic
callus and the others, which were subsequently divided into embryogenic and non-embryogenic callus groups, regardless of plant
species from which the calluses were derived. In the non-embryogenic callus group, the dendrogram was in agreement with the
known taxonomy of the plants. These results indicate that PyMS analysis could be applied for discriminating plant calluses
based on embryogenic capacity and taxonomic classification. 相似文献
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Headd JJ Ban YE Brown P Edelsbrunner H Vaidya M Rudolph J 《Journal of proteome research》2007,6(7):2576-2586
Herein, we study the interfaces of a set of 146 transient protein-protein interfaces in order to better understand the principles of their interactions. We define and generate the protein interface using tools from computational geometry and topology and then apply statistical analysis to its residue composition. In addition to counting individual occurrences, we evaluate pairing preferences, both across and as neighbors on one side of an interface. Likelihood correction emphasizes novel and unexpected pairs, such as the His-Cys pair found in most complexes of serine proteases with their diverse inhibitors and the Met-Met neighbor pair found in unrelated protein interfaces. We also present a visualization of the protein interface that allows for facile identification of residue-residue contacts and other biochemical properties. 相似文献
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Hiroyuki Nakamura Jong-Dae Lee Manabu Ueno Yusuke Miyajima Hyun Seung Ban 《NanoBioTechnology》2007,3(2):135-145
High accumulation and selective delivery of boron into tumor tissues are the most important requirements to achieve efficient
neutron capture therapy of cancers. We focused on liposomal boron delivery system to achieve a large amount of boron delivery
to tumor. We succeeded in the synthesis of the double-tailed boron cluster lipids 4a–c and 5a–c, which has a B12H11S-moiety as a hydrophilic function, by S-alkylation of B12H11SH with bromoacetyl and chloroacetocarbamate derivatives of diacylglycerols. Size distribution of liposomes prepared from
the boron cluster lipid 4b, dimyristoylphosphatidylcholine, polyethyleneglycol-conjugated distearoylphosphatidylethanolamine, and cholesterol was determined
as 100 nm in diameter by an electrophoretic light scattering spectrophotometer. Calcein-encapsulation experiments revealed
that these boronated liposomes are stable at 37 °C in fetal bovine serum solution for 24 h. 相似文献
30.
Kung Ban Sandra Duffy Yelena Khakham Vicky M. Avery Andrew Hughes Oliver Montagnat Kasiram Katneni Eileen Ryan Jonathan B. Baell 《Bioorganic & medicinal chemistry letters》2010,20(20):6024-6029
We report on the discovery of 3-alkylthio-1,2,4-triazine dimers that are potently toxic to Plasmodium falciparum, with single digit nanomolar activity, and up to several thousand-fold lower toxicity to mammalian cells. They are equipotent against chloroquine-resistant strains of P. falciparum. 相似文献