我国弓形虫Chinese 1优势基因型感染对小鼠脑组织铁代谢影响

目的　探讨我国弓形虫Chinese 1优势基因型感染对宿主脑组织铁代谢及脑损伤的影响。方法　将20只C57BL/6（体质量15～17 g）小鼠随机分为对照组和感染组，每组10只。感染组每只小鼠腹腔注射4 000个弓形虫Chinese 1优势基因型TgCtwh3虫株速殖子，对照组小鼠注射等量无菌PBS，饲养6 d后处死小鼠并取其脑组织。采用电感耦合等离子体质谱法（inductively coupled plasma mass spectrometry, ICP⁃MS）检测小鼠脑组织铁元素水平；采用RNA芯片检测两组小鼠脑组织差异基因数目并对功能基因表达情况进行基因本体论（Gene Ontology, GO）功能富集；采用实时荧光定量PCR（fluorescent quantitative real⁃time PCR, qPCR）技术检测小鼠脑组织中弓形虫表面抗原1（Toxoplasma gondii surface antigen 1，TgSAG1）基因及部分锌铁调控蛋白（Zrt⁃ and Irt⁃like protein, ZIP）家族mRNA表达水平；采用光镜和电镜观察小鼠脑组织海马齿轮回（dentate gyrus, DG）超微结构；采用Western blotting检测谷胱甘肽过氧化物酶4（glutathione peroxidase 4, GPx4）蛋白表达水平；采用硫代巴比妥酸（TBA）法检测丙二醛（malondialdehyde, MDA）水平；采用免疫组化检测血管内皮生长因子（vascular endothelial growth factor, VEGF）蛋白表达光密度（optical density, OD）值。结果　光镜下可见感染组小鼠脑组织海马DG区细胞坏死，电镜下见感染组小鼠脑组织海马区出现胞质空泡化、核皱缩坏死、线粒体嵴断裂消融、自噬小体增加等超微结构变化。与对照组相比，感染组小鼠脑组织中铁元素水平上调[（32.92 ± 0.90） µg/g vs.（37.72 ± 1.10） µg/g；t = 3.397, P < 0.01]；RNA芯片检测感染组小鼠脑组织发现721个基因上调、276个基因下调，差异表达基因在金属离子结合能力上有明显富集。与对照组相比，感染组小鼠脑组织金属元素转运体ZIP2 mRNA表达水平上调（t = 8.659，P < 0.05）、GPx4表达下降[（1.046 ± 0.025） vs. （0.720 ± 0.101）；t = 3.129，P < 0.01]）、MDA水平升高[（4.37 ± 0.33） nmol/mgprot vs.（5.93 ± 0.54） nmol/mgprot；t = 2.451，P < 0.05）]、VEGF蛋白平均OD值上调[（0.348 3 ± 0.017 8） vs. （0.490 6 ± 0.010 5）；t = 6.641，P < 0.01]。结论　Chinese 1优势基因型弓形虫感染后，小鼠脑组织中铁元素蓄积、抗氧化能力下调、氧化应激水平升高，提示弓形虫感染可影响宿主脑组织铁代谢而导致脑损伤。     

社区严重精神障碍患者规律面访情况及其影响因素研究

背景严重精神障碍患者因自知力欠缺及高复发性、高致残性等特点，对社会稳定造成严重威胁。做好社区面访管理工作意义重大，通过定期面访患者本人，可以更好地综合评估患者病情，以便及时采取措施，提高管理服务质量。目的了解社区严重精神障碍患者规律面访情况及其影响因素，为提高社区患者的面访服务管理质量提供参考依据。方法2020年10—12月，利用2019年底江苏省严重精神障碍管理系统中建档管理的无锡市严重精神障碍患者基础档案及随访管理信息，分析当年度无锡市社区严重精神障碍患者规律面访情况，采用Logistic回归分析规律面访的影响因素。结果共纳入27 778例研究对象，其规律面访率为81.08%（22 523/27 778）。Logistic回归分析结果显示，非本地户籍〔OR（95%CI）=0.704（0.640，0.775）〕、年龄≤44岁〔OR（95%CI）=0.522（0.472，0.578）〕、学历为高中及以上〔高中/中专OR（95%CI）=0.493（0.446，0.545），大专及以上OR（95%CI）=0.470（0.415，0.532）〕、目前有正式工作〔OR（95%CI）=0.715（0.668，0.766）〕、未婚〔OR（95%CI）=0.746（0.665，0.838）〕、经济状况为非贫困〔OR（95%CI）=0.587（0.517，0.666）〕、没有进行抗精神病药物治疗〔OR（95%CI）=0.491（0.440，0.548）〕、服药时长0~10年〔OR（95%CI）=0.881（0.778，0.998）〕、不是"以奖代补"监护补助对象〔OR（95%CI）=0.807（0.704，0.926）〕、不参加社区康复服务〔OR（95%CI）=0.844（0.716，0.996）〕是患者规律面访的消极影响因素（P<0.05）。结论无锡市社区严重精神障碍患者规律面访率尚需进一步提高，应重点关注非本地户籍、年龄≤44岁、高中及以上学历、目前有正式工作、未婚、经济非贫困、没有进行抗精神病药物治疗、服药时长0~10年、不是监护补助对象和不参加社区康复服务的社区严重精神障碍患者。可通过制定倾斜性政策、开展宣传教育、降低患者病耻感、改善患者疾病认知、加强患者社会支持等措施提高患者规律面访率。     

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.     

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.     

广泛性焦虑障碍住院患者与健康对照者的认知功能比较研究

背景 广泛性焦虑障碍（GAD）是常见的慢性精神疾病，常伴有不同程度的认知功能损害，严重影响患者的生活质量及社会功能。 目的 比较GAD住院患者与健康对照者认知功能的差异。 方法 选取2018年8月至2020年1月在南方医科大学南方医院住院治疗的GAD患者为GAD组（n=30），同期通过广告在南方医科大学南方医院住院患者陪护人员中招募年龄、性别相匹配的健康志愿者为健康对照组（n=30）。使用汉密尔顿焦虑量表（HAMA）、汉密尔顿抑郁量表（HAMD）和Beck自杀意念量表中文版（BSI-CV）进行心理测评，采用精神运动警觉性任务（PVT）、Go/No-go联想任务、N-back任务分别评估认知功能的注意、抑制及工作记忆功能。比较两组一般情况、量表测评总分及认知功能差异，进一步采用多因素Logistic回归分析探究GAD住院患者和健康对照者的认知功能差异。 结果 GAD组HAMA、HAMD总分和最严重情况时BSI-CV总分及最严重情况时存在自杀意念者所占比例高于健康对照组（P<0.05）。N-back任务：GAD组1-back击中目标率（NBACK1a）、2-back击中目标率（NBACK2a）低于健康对照组，1-back击中目标的平均反应时（NBACK1b）长于健康对照组（P<0.05）。多因素Logistic回归分析结果显示，NBACK1a〔OR=0.946，95%CI（0.898，0.997），P=0.038〕、NBACK1b〔OR=1.007，95%CI（1.000，1.014），P=0.042〕是GAD的影响因素。 结论 与健康对照者相比，GAD住院患者的工作记忆较差，需要临床关注。