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141.
142.
银屑病被认为是一种T细胞主导的炎症性疾病,其发病与肠道菌群失调密切相关。脆弱拟杆菌 (Bacteroides fragilis,BF) 可通过调节T细胞的细胞因子表达起抗炎作用。目前尚无脆弱拟杆菌用于治疗银屑病的相关报道,文中率先探究脆弱拟杆菌BF839对银屑病的治疗效果。选择2019年4月至2019年10月广州医科大学附属第二医院就诊的27例银屑病患者,维持原治疗不变,口服脆弱拟杆菌BF839 12周,对比治疗前后银屑病皮损面积与严重程度指数 (Psoriasis area and severity index,PASI) 评分,统计治疗12周后药物减停率。结果表明,12周试验完成率为96.3% (26/27),12周PASI30 (PASIN定义为治疗后PASI评分下降≥N%的患者比例) 为65.4%,PASI50为42.3%,PASI75为19.2%;治疗前PASI评分为9.1±5.9,治疗12周后PASI评分为5.8±4.9,具有显著统计学差异 (P<0.01);治疗12周后皮肤瘙痒程度用视觉模拟量表 (Visual analog scale,VAS) 评分有效率为42.3%,治疗前VAS评分为2.9±2.2,治疗12周后VAS评分为2.3±2.1,无显著统计学差异 (P>0.05)。患者治疗12周内不良反应率为3.8% (1/26),其中便秘1例,药物减停率为60.0%。以上结果提示脆弱拟杆菌BF839可能对银屑病治疗有一定疗效,可降低PASI评分及药物使用率,不良反应少,值得进一步研究。 相似文献
143.
乳酸菌是被公认为安全的食品级微生物,广泛地应用于食品生产、保存以及作为益生菌促进人类健康。鉴于发展有效的投递药物分子策略的需要,乳酸菌成为了极有吸引力的用于口服、鼻饲及阴道进行粘膜投递药物分子的活载体。用乳酸菌作为药物分子的投递载体,安全性好,且可直接合成并投递目标蛋白,显著降低药物生产成本。到目前为止,乳酸菌作为粘膜投递载体,已成功地向粘膜组织投递了一系列功能蛋白用以治疗多种疾病。文中综述了近20年的数据,重点聚焦乳酸菌作为药物分子投递载体的发展和应用,为今后乳酸菌作为活载体的临床研究提供一定参考。 相似文献
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145.
Taoli Liu Dongchang Zeng Zhiye Zheng Zhansheng Lin Yang Xue Tie Li Xianrong Xie Genglu Ma Yao‐Guang Liu Qinlong Zhu 《植物学报(英文版)》2021,63(9):1611-1619
The development of clustered regularly interspaced palindromic repeats (CRISPR)-associated protein (Cas) variants with a broader recognition scope is critical for further improvement of CRISPR/Cas systems. The original Cas9 protein from Streptococcus canis (ScCas9) can recognize simple NNG-protospacer adjacent motif (PAM) targets, and therefore possesses a broader range relative to current CRISPR/Cas systems, but its editing efficiency is low in plants. Evolved ScCas9+ and ScCas9++ variants have been shown to possess higher editing efficiencies in human cells, but their activities in plants are currently unknown. Here, we utilized codon-optimized ScCas9, ScCas9+ and ScCas9++ and a nickase variant ScCas9n++ to systematically investigate genome cleavage activity and cytidine base editing efficiency in rice (Oryza sativa L.). This analysis revealed that ScCas9++ has higher editing efficiency than ScCas9 and ScCas9+ in rice. Furthermore, we fused the evolved cytidine deaminase PmCDA1 with ScCas9n++ to generate a new evoBE4max-type cytidine base editor, termed PevoCDA1-ScCas9n++. This base editor achieved stable and efficient multiplex-site base editing at NNG-PAM sites with wider editing windows (C−1–C17) and without target sequence context preference. Multiplex-site base editing of the rice genes OsWx (three targets) and OsEui1 (two targets) achieved simultaneous editing and produced new rice germplasm. Taken together, these results demonstrate that ScCas9++ represents a crucial new tool for improving plant editing. 相似文献
146.
Junping Li Libin Liang Li Jiang Qian Wang Xia Wen Yuhui Zhao Pengfei Cui Yaping Zhang Guangwen Wang Qibing Li Guohua Deng Jianzhong Shi Guobin Tian Xianying Zeng Yongping Jiang Liling Liu Hualan Chen Chengjun Li 《PLoS pathogens》2021,17(2)
Posttranslational modifications, such as SUMOylation, play specific roles in the life cycle of invading pathogens. However, the effect of SUMOylation on the adaptation, pathogenesis, and transmission of influenza A virus (IAV) remains largely unknown. Here, we found that a conserved lysine residue at position 612 (K612) of the polymerase basic protein 1 (PB1) of IAV is a bona fide SUMOylation site. SUMOylation of PB1 at K612 had no effect on the stability or cellular localization of PB1, but was critical for viral ribonucleoprotein (vRNP) complex activity and virus replication in vitro. When tested in vivo, we found that the virulence of SUMOylation-defective PB1/K612R mutant IAVs was highly attenuated in mice. Moreover, the airborne transmission of a 2009 pandemic H1N1 PB1/K612R mutant virus was impaired in ferrets, resulting in reversion to wild-type PB1 K612. Mechanistically, SUMOylation at K612 was essential for PB1 to act as the enzymatic core of the viral polymerase by preserving its ability to bind viral RNA. Our study reveals an essential role for PB1 K612 SUMOylation in the pathogenesis and transmission of IAVs, which can be targeted for the design of anti-influenza therapies. 相似文献
147.
Zhou Yuanhao Ye Xiaolin Wang Baikui Ying Jiafu Zeng Zihan Tang Li Wang Qi Zou Peng Zhan Xiaoli Fu Luoqin 《International journal of peptide research and therapeutics》2021,27(3):1605-1613
International Journal of Peptide Research and Therapeutics - Pidotimod has been shown to exhibit immunomodulatory activities and exert protective effects against bacterial infections. This study... 相似文献
148.
Cui Liu Qian He Linlin Zeng Ling Shen Qiaomei Luo Wentao Zhang Xia Zhou Jun Wan 《化学与生物多样性》2021,18(12):e2100705
Emerging evidence suggests that a high-fat diet (HFD) can influence endoplasmic reticulum (ER) stress and gut microbiota. Crataegi Fructus is a traditional Chinese herb widely used in formulas for dyspepsia, with Dashanzha Pill composed of raw Crataegi Fructus (DR) being a representative drug. Processing products of Crataegi Fructus, however, have a stronger pro-digestive effect, and we hypothesized that Dashanzha Pill composed of charred Crataegi Fructus (DC) is more effective. We found that the contents of glucose 1-phosphate and luteolin in DR and DC were substantially different via ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry. DC outperformed DR in improving histopathological changes, increasing gastrin and motilin, and decreasing vasoactive intestinal peptides in rats with HFD induced dyspepsia. Fecal microbiota analysis revealed that DC could restore the disturbed intestinal microbiota composition, including that of Bacteroides, Akkermansia, and Intestinimonas to normal levels. Furthermore, DC significantly reduced the mRNA and protein levels of glucose-regulated protein 78, protein kinase R-like ER kinase, and eukaryotic initiation factor 2α. Taken together, DC outperformed DR in relieving dyspepsia by regulating gut microbiota and alleviating ER stress. 相似文献
149.
Li Jingyan Wang Yong Chen Juan Zhang Siyuan Zeng Ying 《International journal of peptide research and therapeutics》2021,27(4):2559-2570
International Journal of Peptide Research and Therapeutics - Atrial natriuretic peptide (ANP) is a type of peptide hormone secreted by atrial cells, which has many important biological functions... 相似文献
150.
Wei Liu Chunyu Wang Shengli Wang Kai Zeng Shan Wei Ning Sun Ge Sun Manlin Wang Renlong Zou Wensu Liu Lin Lin Huijuan Song Zining Jin Yue Zhao 《International journal of biological sciences》2021,17(1):188
Androgen receptor (AR) and its variants play vital roles in development and progression of prostate cancer. To clarify the mechanisms involved in the enhancement of their actions would be crucial for understanding the process in prostate cancer and castration-resistant prostate cancer transformation. Here, we provided the evidence to show that pre-mRNA processing factor 6 (PRPF6) acts as a key regulator for action of both AR full length (AR-FL) and AR variant 7 (AR-V7), thereby participating in the enhancement of AR-FL and AR-V7-induced transactivation in prostate cancer. In addition, PRPF6 is recruited to cis-regulatory elements in AR target genes and associates with JMJD1A to enhance AR-induced transactivation. PRPF6 also promotes expression of AR-FL and AR-V7. Moreover, PRPF6 depletion reduces tumor growth in prostate cancer-derived cell lines and results in significant suppression of xenograft tumors even under castration condition in mouse model. Furthermore, PRPF6 is obviously highly expressed in human prostate cancer samples. Collectively, our results suggest PRPF6 is involved in enhancement of oncogenic AR signaling, which support a previously unknown role of PRPF6 during progression of prostate cancer and castration-resistant prostate cancers. 相似文献