Mendelian randomization as a tool to gain insights into the mosaic causes of autoimmune diseases

Autoimmune diseases (ADs) are a broad range of disorders which are characterized by long-term inflammation and tissue damage arising from an immune response against one's own tissues. It is now widely accepted that the causes of ADs include environmental factors, genetic susceptibility and immune dysregulation. However, the exact etiology of ADs has not been fully elucidated to date. Because observational studies are plagued by confounding factors and reverse causality, no firm conclusions can be drawn about the etiology of ADs. Over the years, Mendelian randomization (MR) analysis has come into focus, offering unique perspectives and insights into the etiology of ADs and promising the discovery of potential therapeutic interventions. In MR analysis, genetic variation (alleles are randomly dispensed during meiosis, usually irrespective of environmental or lifestyle factors) is used instead of modifiable exposure to explore the link between exposure factors and disease or other outcomes. Therefore, MR analysis can provide a valuable method for exploring the causal relationship between different risk factors and ADs when its inherent assumptions and limitations are fully considered. This review summarized the recent findings of MR in major ADs, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS), and type 1 diabetes mellitus (T1DM), focused on the effects of different risk factors on ADs risks. In addition, we also discussed the opportunities and challenges of MR methods in ADs research.     

Novel Method for Fetal and Maternal Heart Rate Measurements Using 2-D Ultrasound Color Doppler Flow Images

Fetal heart rate (FHR) and maternal heart rate (MHR) are important indicators of fetal well-being during pregnancy. A common method in clinical examination is to estimate the FHR using the Doppler shift of echoes from umbilical artery blood flow based on an ultrasound pulsed-wave (PW) Doppler technique. Similarly, a sampling gate can be located at the maternal blood flow to measure MHR using PW Doppler. Ultrasound color Doppler flow imaging (CDFI) is one of the most commonly used imaging modes for clinical fetal examinations. Color coding is employed to display the blood flow velocity and direction in color grades according to the Doppler shift. Continuous CDF images contain dynamic changes characteristics of the blood flow. The periodic characteristics can be used to obtain heart rate information. Therefore, here we propose a novel method to measure FHR and MHR simultaneously using CDF images. The proposed method calculates the histogram of color similarity of CDF images to initially extract the periodic characteristics of the CDF image sequence. The histogram of color similarity function is then processed by a bandpass filter and autocorrelation operation to reduce noise and enhance periodicity. Finally, peak detection is performed on the processed signal to obtain the period and estimate the heart rate. The proposed method can measure the FHR and MHR in parallel after selecting two regions containing the umbilical artery and maternal blood flow, respectively. Thus, the method has high computational efficiency. The proposed method was evaluated on a Doppler flow phantom and clinical CDF images and then compared with the PW Doppler method. The correlation analysis and Bland–Altman plots reveal that the proposed method agrees well with the PW Doppler. It is a sanity check method for real-time clinical FHR and MHR measurements.     

下一代诊断病理学

随着人类基因组测序、生物大数据信息分析、分子病理检测和人工智能辅助病理诊断等技术进步及其应用, 临床医学发展迈向精准诊疗时代。这一时代背景下, 传统诊断病理学迎来前所未有的历史机遇, 正在向"下一代诊断病理学(next-generation diagnostic pathology)"迈进。下一代诊断病理学以病理形态和临床信息为诊断基础, 以分子检测与生物信息分析、智慧制样与流程质控、智能诊断与远程会诊、病灶活体可视化与"无创"病理诊断等创新前沿交叉技术为主要特征, 以多组学和跨尺度整合诊断为病理报告内容, 实现对疾病的"最后诊断", 并预测疾病演进和结局、建议治疗方案和评估治疗反应, 形成新的疾病诊断"金标准"。未来, 需要激发病理学科创新活力, 加快下一代诊断病理学成熟和应用, 重塑病理学科理论和技术体系, 发挥诊断病理学在疾病"防、诊、治、养"等过程中的重要作用, 促进临床医学进一步发展, 服务健康中国战略。     

重组人表皮生长因子凝胶联合CO2点阵激光治疗增生性瘢痕的效果观察

目的观察重组人表皮生长因子凝胶联合CO₂点阵激光治疗烧伤及创伤后增生性瘢痕的临床效果。 方法选择2020年12月至2021年10月安徽医科大学第一附属医院烧伤与创面修复外科收治的20例增生性瘢痕患者，按照随机数字表法将患者分为联合治疗组及单纯激光治疗组，每组10例。术前均对2组患者术区进行拍照存像、消毒、擦干，局部均匀涂抹5%复方利多卡因乳膏后以无菌薄膜封闭保护60 min，擦去乳膏后再次消毒术区。术中使用CO₂点阵激光治疗仪对患者瘢痕部位进行扫描，根据患者增生性瘢痕厚度选定合适的机器参数，维持机器频率300 Hz及密度5%，在20～30 J调整能量参数的大小，时间间隔1 s，保证点阵矩形完全覆盖增生瘢痕，允许2次激光形成的热损伤矩阵之间存在25%面积的重叠。术后即刻冷敷创面60 min，冷敷结束至术后1周，单纯激光治疗组不外用任何药物，联合治疗组术区加用重组人表皮生长因子凝胶外用，3次/d。术后3 d治疗部位不碰水，若出现感染情况，可以加用抗生素软膏，点状损伤创面外痂皮未掉落完全时禁止擦洗创面，禁止直接剥除痂皮，禁止术区涂抹化妆品等，避免接受阳光直射。于第1次激光治疗后2个月进行第2次激光治疗，以2次CO₂点阵激光治疗为1个疗程，1个疗程治疗后间隔2个月待术区稳定后行疗效判断，计算2组患者治疗的总有效率；根据温哥华瘢痕量表(VSS)与患者与观察者瘢痕评估量表(POSAS)对患者治疗前、第1次激光治疗后2个月、第2次激光治疗后2个月瘢痕的各项指标进行评分。数据比较采用重复测量方差分析和χ²检验。 结果(1)治疗1个疗程后2个月，单纯激光治疗组与联合治疗组患者治疗的总有效率分别为80%(8/10)、90%(9/10)，2组间比较差异无统计学意义(χ²＝2.40，P＝0.49)。(2)对2组VSS评分的各项指标进行比较，其中疼痛、瘙痒、柔软度及厚度评分的组内及组间各时相点比较，差异均无统计学意义(P>0.05)。治疗前、第1次激光治疗后2个月及第2次激光治疗后2个月，单纯激光治疗组VSS评分中色泽评分分别为(1.9±0.7)、(1.9±0.1)、(1.8±1.0)分，联合治疗组分别为(2.9±0.7)、(2.8±0.6)、(1.9±0.7)分，2组在不同时相点组内比较，差异有统计学意义(F＝ 26.143，P<0.05)；2组组间不同时相点比较，差异有统计学意义(F＝6.753，P＝0.018)。治疗前、第1次激光治疗后2个月及第2次激光治疗后2个月，单纯激光治疗组VSS评分中血管分布评分分别为(1.8±1.0)、(1.7±0.7)、(1.5±1.0)分，联合治疗组分别为(2.6±0.5)、(2.5±0.5)、(1.7±0.8)分，2组在不同时相点组内比较，差异有统计学意义(F＝17.603，P<0.05)，2组组间不同时相点比较，差异无统计学意义(F＝ 2.538，P＝0.129)。(3)对2组POSAS评分的各项指标进行比较，其中厚度、粗糙度、柔软度和表面积评分的组内及组间各时相点比较，差异均无统计学意义(P>0.05)。治疗前、第1次激光治疗后2个月及第2次激光治疗后2个月，单纯激光治疗组POSAS评分中色泽评分分别为(4.9±2.6)、(4.1±0.8)、(3.5±2.0)分，联合治疗组分别为(7.6±1.1)、(6.8±1.4)、(5.4±1.8)分，2组在不同时相点组内比较，差异有统计学意义(F＝ 26.509，P<0.05)，2组组间不同时相点比较，差异有统计学意义(F＝ 8.973，P＝0.008)。治疗前、第1次激光治疗后2个月及第2次激光治疗后2个月，单纯激光治疗组POSAS评分中血管分布评分分别为(4.4±2.1)、(3.9±0.9)、(3.5±1.6)分，联合治疗组分别为(6.3±1.1)、(5.7±2.0)、(4.5±1.6)分，2组在不同时相点组内比较，差异有统计学意义(F＝ 20.118，P<0.05)，2组组间不同时相点比较，差异有统计学意义(F＝ 5.744，P＝0.028)。 结论重组人表皮生长因子凝胶联合CO₂点阵激光及单独使用CO₂点阵激光治疗增生性瘢痕均效果明确，但联合使用重组人表皮生长因子凝胶能有效促进创面愈合、改善瘢痕组织血管分布和减少局部色素沉着。     

What Should We Focus on in Sepsis Fluid Resuscitation?--A Research Based on Scientometrics and Visual Analysis

Sepsis is a life-threatening condition and a global disease burden.Heterogeneous syndrome is defined as severe organ dysfunction caused by a dysregulated host response to infection,with renewed emphasis on the immune pathophysiology.Researchers worldwide constantly update the diagnostic criteria of sepsis and have introduced concepts such as“sepsis-3”“Surviving Sepsis Campaign(SSC)”“Early Goal-Directed Therapy(EGDT)”,the 3-h and 6-h bundles to an hour-1 bundle[1],“limited ventilation”“the best PEEP[2]”,and“Lung Protective-Ventilation”.Despite all efforts of experimental and clinical research during the last three decades,the ability to positively influence the course and outcome of the syndrome remains limited.     

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。     

Dose optimization with population pharmacokinetics of ritonavir-boosted lopinavir for Thai people living with HIV with and without active tuberculosis

BackgroundPrior to dolutegravir availability, ritonavir-boosted lopinavir (LPV/r) was an alternative recommendation when first-line drugs could not be used. A high concentration of protease inhibitors was observed in the Thai people living with HIV (PLWH). Thus, dose reduction of LPV/r may be possible. However, the pharmacokinetics and dose optimization of LPV/r have never been investigated. This study aimed to develop a population pharmacokinetic model of LPV/r and provide dosage optimization in Thai PLWH.MethodsLPV and RTV trough concentrations from Thai PLWH were combined with intensive data. The data were analyzed by the nonlinear mixed-effects modeling approach. The influence of RTV concentration on LPV oral clearance (CL/F) was investigated.ResultsRifampicin (RIF) use increased LPV and RTV CL/F by 2.16-fold and 1.99-fold, respectively. The reduced dose of 300/75 and 200/150 mg twice daily provided a comparable percentage of patients achieving LPV target trough concentration to the standard dose for PI-naïve patients. For HIV/TB co-infected patients receiving RIF who could not tolerate the recommended dose, the reduced dose of 600/150 mg twice daily was recommended.ConclusionThe population pharmacokinetic model was developed by integrating the interaction between LPV and RTV. The reduced LPV/r dosage offers sufficient LPV exposure for Thai PLWH.     

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.