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201.
Hayato Terayama Takayuki Yoshimoto Shuichi Hirai Munekazu Naito Ning Qu Naoyuki Hatayama Shogo Hayashi Kana Mitobe Jun-ichi Furusawa Izuru Mizoguchi Takeshi Kezuka Hiroshi Goto Kaori Suyama Hiroshi Moriyama Kou Sakabe Masahiro Itoh 《PloS one》2014,9(4)
The testis is an organ with immune privilege. The comprehensive blood–testis barrier formed by Sertoli cells protects autoimmunogenic spermatozoa and spermatids from attack by the body’s immune system. The interleukin (IL)-6/IL-12 family cytokines IL-12 (p35/p40), IL-23 (p19/p40), IL-27 (p28/Epstein-Barr virus−induced gene 3 [EBI3]), and IL-35 (p35/EBI3) play critical roles in the regulation of various immune responses, but their roles in testicular immune privilege are not well understood. In the present study, we investigated whether these cytokines are expressed in the testes and whether they function in the testicular immune privilege by using mice deficient in their subunits. Expression of EBI3 was markedly increased at both mRNA and protein levels in the testes of 10- or 12-week-old wild-type mice as compared with levels in 2-week-old mice, whereas the mRNA expression of p40 was markedly decreased and that of p35 was conserved between these two groups. Lack of EBI3, p35, and IL-12 receptor β2 caused enhanced infiltration of lymphocytes into the testicular interstitium, with increased interferon-γ expression in the testes and autoantibody production against mainly acrosomal regions of spermatids. Spermatogenic disturbance was more frequently observed in the seminiferous tubules, especially when surrounded by infiltrating lymphocytes, of these deficient mice than in those of wild-type mice. In particular, p35-deficient mice showed the most severe spermatogenic disturbance. Immunohistochemical analyses revealed that endothelial cells and peritubular cells in the interstitium were highly positive for p35 at both ages, and CD163+ resident macrophages positive for p35 and EBI3, possibly producing IL-35, were also detected in the interstitium of 12-week-old mice but not those of 2-week-old mice. These results suggest that p35 helps in maintaining the testicular immune privilege, in part in an IL-35-dependent manner. 相似文献
202.
为研究从玫瑰黄链霉菌Men-myco-93-63中克隆到的,与天蓝色链霉菌M 145中的一个重要负调控基因nsd A基因同源的nsdA_(mgh)基因的功能,本文构建了nsd A_(mgh)基因破坏型重组质粒pSRNA2500(pKC1139::1.5 kb nsdA_(mgh)::1.0 kb Km~r),转化ET12567(pUZ8002)获得接合转移供体菌ET12567(pUZ8002,pSRNA2500),通过接合转移将重组质粒导入玫瑰黄链霉菌Men-myco-93-63中。在高温和抗生素双重筛选压力下,筛选得到表型为Am~sKm~r的nsd A_(mgh)基因阻断突变株,通过PCR、Dot bloting和Southern blotting验证了突变株中的nsdA_(mgh)基因已被正确阻断。与出发菌株相比,突变株在摇瓶水平上对棉花黄萎病菌的抑制能力提高了一倍。 相似文献
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204.
Arisha Mohamed Hamed Hui Yan Ahmad Muhammad Qadir Wei Tang Meng Kou Yaju Liu Xin Wang Yungang Zhang Qiang Li 《Plant Molecular Biology Reporter》2021,39(3):473-488
Plant Molecular Biology Reporter - Sweetpotato (Ipomoea batatas L), the herbaceous plant cultivated for its starchy storage roots, has a complex genome (2n?=?6x?=?90) with... 相似文献
205.
Wei-Qing Liu Wen-Liang Li Shu-Min Ma Lei Liang Zhi-Yong Kou Jun Yang 《Translational oncology》2021,14(3):101011
In this study, we aimed to uncover genes that drive the pathogenesis of liver metastasis in colorectal cancer (CRC), and identify effective genes that could serve as potential therapeutic targets for treating with colorectal liver metastasis patients based on two GEO datasets. Several bioinformatics approaches were implemented. First, differential expression analysis screened out key differentially expressed genes (DEGs) across the two GEO datasets. Based on gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, we identified the enrichment functions and pathways of the DEGs that were associated with liver metastasis in CRC. Second, immune infiltration analysis identified key immune signature gene sets associated with CRC liver metastasis, among which two key immune gene families (CD and CCL) identified as key DEGs were filtered by protein-protein interaction (PPI) network. Some of the members in these gene families were associated with disease free survival (DFS) or overall survival (OS) in two subtypes of CRC, namely COAD and READ. Finally, functional enrichment analysis of the two gene families and their neighboring genes revealed that they were closely associated with cytokine, leukocyte proliferation and chemotaxis. These results are valuable in comprehending the pathogenesis of liver metastasis in CRC, and are of seminal importance in understanding the role of immune tumor infiltration in CRC. Our study also identified potentially effective therapeutic targets for liver metastasis in CRC including CCL20, CCL24 and CD70. 相似文献
206.
Lei Liu Wanbing Liu Yan Liu Guomei Kou Yaqiong Zheng Liping Cai Shengdian Wang Shangen Zheng 《Asia-Pacific Journal of Blood Types and Genes》2021,5(1):41-47
This paper aimed to analyze antibody responses to SARS-CoV-2 in various populations. Two hundred and six COVID-19 patients, 46 convalescent patients, and 270 healthy population were enrolled. Antibodies against nucleocapsid protein (N) and spike protein''s receptor-binding domain (RBD), and neutralizing antibody were detected. The results demonstrated both anti-N and anti-RBD antibodies could be detected in about 80% of COVID-19 patients and 90% of convalescent patients, while no antibodies could be detected in some convalescents and patients even after 14 days post-onset of symptoms. The level of anti-RBD antibody strongly correlated with the neutralizing activity of sera from these two cohorts. The titer of neutralizing antibody was lower in convalescents than that in active COVID-19 patients. In addition, the titer of neutralizing antibody was less than 1:80 in none of the severe COVID-19 patients, 18.8% in non-severe COVID-19 patients, and 32.6% in convalescents. The study suggests that the level of anti-RBD antibody is closely related to neutralization activity in COVID-19 patients and convalescents. Some SARS-CoV-2-infected cases trigger a weak antiviral immune response, and the level of neutralizing antibody may have a faster decay rate. 相似文献
207.
Tissue factor (TF), the primary initiator of the coagulation cascade, plays a critical role in hemostasis and thrombosis, and inhibition of TF activity appears to be an attractive target for the treatment of cardiovascular diseases. However, few selective small-molecule inhibitors of TF are available, and the present assays for measuring TF activity are relatively expensive and complex. The authors present a simple and high-throughput chromogenic assay for screening TF inhibitors based on using commercial human prothrombin complex instead of purified coagulation factors, reducing the dosage, and performing with a one-stage procedure. In the optimized assay, <45 μL cell lysates was incubated with Tris-CaCl(2) buffer (pH 7.3) containing human prothrombin complex at 37°C for 15 min in 96-well or 384-well plates. Tris-EDTA buffer (pH 8.4) containing chromogenic substrate Xa was then added and the absorbance measured at 405 nm. This simplified assay was more sensitive or precise than some reported methods for TF procoagulant activities. Two known active compounds (curcumin and simvastatin) inhibiting TF activity were tested by the simplified assay to validate the screening method. Furthermore, berberine and cryptotanshinone suppressed TF activity induced by lipopolysaccharides in human monocytes by this assay and might be promising new TF inhibitors. 相似文献
208.
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210.
Kou I Takahashi A Urano T Fukui N Ito H Ozaki K Tanaka T Hosoi T Shiraki M Inoue S Nakamura Y Kamatani N Kubo M Mori S Ikegawa S 《PloS one》2011,6(5):e19641
Osteoporosis is a common disease characterized by low bone mass, decreased bone quality and increased predisposition to fracture. Genetic factors have been implicated in its etiology; however, the specific genes related to susceptibility to osteoporosis are not entirely known. To detect susceptibility genes for osteoporosis, we conducted a genome-wide association study in Japanese using ∼270,000 SNPs in 1,747 subjects (190 cases and 1,557 controls) followed by multiple levels of replication of the association using a total of ∼5,000 subjects (2,092 cases and 3,114 controls). Through these staged association studies followed by resequencing and linkage disequilibrium mapping, we identified a single nucleotide polymorphism (SNP), rs7605378 associated with osteoporosis. (combined P = 1.51×10−8, odds ratio = 1.25). This SNP is in a previously unknown gene on chromosome 2q33.1, FONG. FONG is predicted to encode a 147 amino-acid protein with a formiminotransferase domain in its N-terminal (FTCD_N domain) and is ubiquitously expressed in various tissues including bone. Our findings would give a new insight into osteoporosis etiology and pathogenesis. 相似文献