Metabolism of non-steroidal anti-inflammatory drugs (NSAIDs) by Streptomyces griseolus CYP105A1 and its variants

In the field of drug development, technology for producing human metabolites at a low cost is required. In this study, we explored the possibility of using prokaryotic water-soluble cytochrome P450 (CYP) to produce human metabolites. Streptomyces griseolus CYP105A1 metabolizes various non-steroidal anti-inflammatory drugs (NSAIDs), including diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, meclofenamic acid, and ibuprofen. CYP105A1 showed 4′-hydroxylation activity towards diclofenac, mefenamic acid, flufenamic acid, tolfenamic acid, and meclofenamic acid. It should be noted that this reaction specificity was similar to that of human CYP2C9. In the case of mefenamic acid, another metabolite, 3′-hydroxymethyl mefenamic acid, was detected as a major metabolite. Substitution of Arg at position 73 with Ala in CYP105A1 dramatically reduced the hydroxylation activity toward diclofenac, flufenamic acid, and ibuprofen, indicating that Arg73 is essential for the hydroxylation of these substrates. In contrast, substitution of Arg84 with Ala remarkably increased the hydroxylation activity towards diclofenac, mefenamic acid, and flufenamic acid. Recombinant Rhodococcus erythrocyte cells expressing the CYP105A1 variant R84A/M239A showed complete conversion of diclofenac into 4′-hydroxydiclofenac. These results suggest the usefulness of recombinant R. erythropolis cells expressing actinomycete CYP, such as CYP105A1, for the production of human drug metabolites.     

HBV基因型的研究现状与发展趋势探讨

[摘要]?目前研究已知HBV有多种基因型，不同基因型在不同的种族、地域方面分布特点不同且HBV基因型是造成慢性感染自然史差异的原因之一，它们在感染的临床表现和抗病毒治疗的反应中起着重要作用。检测HBV基因型和了解HBV不同基因型对疾病预后的影响，对评估患者疾病结局和指导临床规划最佳治疗方案具有重要意义。 　　[关键词]　乙型肝炎病毒；基因型；基因突变；治疗     

基于CNKI的中医药治疗癫痫的知识图谱分析＊

目的 运用科学知识图谱的手段，分析中医药治疗癫痫的研究进程并提炼重点。方法 设置检索时间为1990年至2020年，检索对象为中国知网（CNKI）该领域的相关文献，运用CiteSpace软件科学、准确地分析这些文献的作者信息、研究（发文）机构、关键词情况。结果 共计纳入文献793篇，马融-张喜莲、刘金民、谢炜、王洪图-张丽萍等领导核心作者团队，北京、广州以及广西中医药大学、天津中医药大学第一附属医院、南方医科大学等单位为主要进行相关研究的机构，高频关键词包括大鼠、难治性癫痫、小儿癫痫、海马、脑电图等，作用机制、网络药理学、肠道菌群、氧化应激、分子生物学等为近年来的热点与前沿。结论 通过借用知识图谱的分析能帮助提炼国内中医药治疗癫痫研究领域的重点，全面分析并科学判断近年来该领域的热点及前沿，为未来的研究夯实基础并把握方向。     

细胞因子在分化型甲状腺癌诊疗中的应用进展北大核心

甲状腺癌是内分泌系统常见的恶性肿瘤之一,其发病率呈逐年上升趋势。甲状腺癌以分化型甲状腺癌(differentiated thyroid carcinoma, DTC)为主,尽管多数DTC患者经规范化治疗后预后良好,但由于部分肿瘤的病理类型侵袭性较高或肿瘤组织分化程度较低,病情进展迅速导致患者总生存时间显著缩短。近年来,有关炎症与肿瘤之间相关性的研究越来越多,炎性微环境的改变在肿瘤发病机制中的作用逐渐被证实,更多的证据表明细胞因子可作为肿瘤的良恶性鉴别、预后判断提示及诊疗方案选择等的重要参考依据。本文就部分细胞因子在DTC诊疗中的应用进展进行论述,旨在为DTC的诊疗与预后判断等提供参考依据。     

颞下颌关节骨关节病术后不同辅助治疗效果评价

目的    评价颞下颌关节骨关节病（temporomandibular joint osteoarthrosis，TMJOA）术后不同辅助治疗方法的临床效果，为术后康复治疗提供参考。方法    选取2015年6月至2021年11月于中国医科大学附属口腔医院口腔颌面外科行颞下颌关节盘松解复位固定手术的191例TMJOA患者进行回顾性分析。术后行牙合垫治疗+常规功能训练的63例患者记为牙合垫组，行几丁糖关节腔内注射治疗+常规功能训练的57例患者记为注射组，仅行常规功能训练的71例患者记为对照组。对3组患者治疗前后的疼痛视觉模拟评分法（VAS）评分、最大张口度、下颌运动分、肌肉压诊分进行比较分析。结果    治疗前，3组各项评价指标比较，差异均无统计学意义（均P > 0.05）。治疗后3个月，3组各项评价指标总的比较，差异均有统计学意义（均P < 0.05）；关于VAS评分、下颌运动分、肌肉压诊分方面，分值由低至高依次为注射组、牙合垫组、对照组，而最大张口度由大至小依次为注射组、牙合垫组、对照组，差异均有统计学意义（P < 0.05）；且3组各项评价指标结果均明显优于治疗前（均P < 0.05）。结论    TMJOA患者行颞下颌关节盘松解复位固定手术后采取适当辅助治疗和功能训练均能显著改善颞下颌关节功能，其中几丁糖关节腔内注射治疗结合常规功能训练的效果较佳。     

ArgD of Mycobacterium tuberculosis is a functional N-acetylornithine aminotransferase with moonlighting function as an effective immune modulator

Mycobacterium tuberculosis (M. tuberculosis) encodes an essential enzyme acetyl ornithine aminotransferase ArgD (Rv1655) of arginine biosynthetic pathway which plays crucial role in M. tuberculosis growth and survival. ArgD catalyzes the reversible conversion of N-acetylornithine and 2 oxoglutarate into glutamate-5-semialdehyde and L-glutamate. It also possesses succinyl diaminopimelate aminotransferase activity and can thus carry out the corresponding step in lysine biosynthesis. These essential roles played by ArgD in amino acid biosynthetic pathways highlight it as an important metabolic chokepoint thus an important drug target. We showed that M. tuberculosis ArgD rescues the growth of ΔargD E. coli grown in minimal media validating its functional importance. Phylogenetic analysis of M. tuberculosis ArgD showed homology with proteins in gram positive bacteria, pathogenic and non-pathogenic mycobacteria suggesting the essentiality of this protein. ArgD is a secretory protein that could be utilized by M. tuberculosis to modulate host innate immunity as its moonlighting function. In-silico analysis predicted it to be a highly antigenic protein. The recombinant ArgD protein when exposed to macrophage cells induced enhanced production of pro-inflammatory cytokines TNF, IL6 and IL12 in a dose dependent manner. ArgD also induced the increased production of innate immune effector molecule NOS2 and NO in macrophages. We also demonstrated ArgD mediated activation of the canonical NFkB pathway. Notably, we also show that ArgD is a specific TLR4 agonist involved in the activation of pro-inflammatory signaling for sustained production of effector cytokines. Intriguingly, ArgD protein treatment activated macrophages to acquire the M1 phenotype through the increased surface expression of MHCII and costimulatory molecules CD80 and CD86. ArgD induced robust B-cell response in immunized mice, validating its antigenicity potential as predicted by the in-silico analysis. These properties of M. tuberculosis ArgD signify its functional plasticity that could be exploited as a possible drug target to combat tuberculosis.