黄芩苷改善肿瘤缺氧微环境抑制乳腺癌移植瘤的生长＊

目的 通过观察黄芩苷对乳腺癌组织毛细血管通透性（Capillary Vessel Permeability，CVP）、赖氨酰氧化酶（Lysyl Oxidase，LOX）及血清丙二醛（Malondialdehyde，MDA）等相关指标的影响，探讨黄芩苷可能的抗乳腺癌作用机制。方法 通过在裸鼠皮下接种MDA-MB-231乳腺癌细胞株建立乳腺癌移植瘤模型；实验分为模型组、黄芩苷组、阿霉素组、黄芩苷+阿霉素组。于接种第7日开始：黄芩苷组每天灌胃黄芩苷水溶液（100 mg·kg^-1），连续14天；阿霉素组每3天腹腔注射一次阿霉素（5mg·kg^-1），共用药5次；模型组每天灌胃生理盐水（10 mL·kg^-1），连续14天；黄芩苷+阿霉素组每天灌胃黄芩苷水溶液（100 mg·kg^-1），连续14天，并每3天腹腔注射一次阿霉素5 mg·kg^-1，共5次。给药期间监测移植瘤体积；紫外可见分光光度计620 nm下测OD值来反映黄芩苷对肿瘤毛细血管通透性的影响；硫代巴比妥酸（Thiobarbituric acid，TBA）比色法检测黄芩苷对裸鼠血清中丙二醛（MDA）的影响；免疫组化染色法检测乳腺癌组织中赖氨酰氧化酶（LOX）的表达情况。结果 ①与模型组比较，黄芩苷组、阿霉素组、黄芩苷+阿霉素组瘤体重量均明显减轻（P<0.05）；黄芩苷+阿霉素组瘤体重量较阿霉素组明显减轻（P<0.05）。②与模型组比较，黄芩苷组降低乳腺癌组织毛细血管的通透性，而阿霉素组则增加肿瘤组织中毛细血管的通透性，差异均具有统计学意义（P<0.05）。③黄芩苷组能够明显抑制荷瘤裸鼠血清MDA的表达，与模型组比较差异有显著统计学意义（P<0.01）；阿霉素组促进MDA的表达，与模型组比较差异有统计学意义；黄芩苷+阿霉素组促进MDA的表达，与模型组比较差异无统计学意义。④与模型组比较，黄芩苷组裸鼠乳腺癌组织LOX的表达显著下调（P<0.01），阿霉素组肿瘤组织中LOX表达增加（P<0.05）；黄芩苷+阿霉素组能下调裸鼠乳腺癌组织LOX的表达，与模型组比较差异无统计学意义。结论 黄芩苷能够明显抑制乳腺癌移植瘤的生长，其机制可能与黄芩苷降低肿瘤组织毛细血管的通透性，抑制裸鼠血清中丙二醛、乳腺癌组织中赖氨酰氧化酶的表达，从而改变肿瘤缺氧微环境有关。     

Angiotensin (1−7) peptide replacement therapy with plasma transfusion in COVID-19

AimTo determine whether convalescent angiotensin (1?7) peptide replacement therapy with plasma (peptide plasma) transfusion can be beneficial in the treatment of critically ill patients with severe coronavirus 2 (SARS-CoV-2) infection.Study designCase series of 9 critically ill patients with laboratory-confirmed COVID-19 who met the following criteria: severe pneumonia with rapid progression and continuously high viral load despite antiviral treatment.Peptide plasma: Plasma with angiotensin (1?7) content 8–10 times higher than healthy plasma donors was obtained from suitable donors. Peptide plasma transfusion was applied to 9 patients whose clinical status and/or laboratory profile deteriorated and who needed intensive care for 2 days.ResultsIn our COVID-19 cases, favipiravir, low molecular weight heparin treatment, which is included in the treatment protocol of the ministry of health, was started. Nine patients with oxygen saturation of 93% and below despite nasal oxygen support, whose clinical and/or laboratory deteriorated, were identified. The youngest of the cases was 36 years old, and the oldest patient was 85 years old. 6 of the 9 cases had male gender. 3 cases had been smoking for more than 10 years. 4 cases had at least one chronic disease.In all of our cases, SARS CoV2 lung involvement was bilateral and peptide plasma therapy was administered in cases when oxygen saturation was 93% and below despite nasal oxygen support of 5 liters/minute and above, and intensive care was required. Although it was not reflected in the laboratory parameters in the early period, 8 patients whose saturations improved with treatment were discharged without the need for intensive care. However, a similar response was not obtained in one case. Oxygen requirement increased gradually and, he died in intensive care process. An increase of the platelet count was observed in all cases following the peptide plasma treatment.ConclusionIn this preliminary case series of 9 critically ill patients with COVID-19, administration of plasma containing angiotensin (1?7) was followed by improvement in their clinical status. The limited sample size and study design preclude a definitive statement about the potential effectiveness of this treatment, and these observations require evaluation in clinical trials.     

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.     

原发性干燥综合征生物标志物的研究进展

目前原发性干燥综合征(pSS)诊断仍然依赖于侵入性小涎腺活检手术,常导致其早期诊断异常艰难,因此筛选特定生物标志物可能对pSS诊断和个体化治疗极为有益。本文回顾传统标志物及与B细胞活化和表观遗传相关的新标志物,并综述组学标志物研究进展。尽管生物标志物前景较好,但其可靠性仍需扩大样本量进行验证。     

Redox active or thiol reactive? Optimization of rapid screens to identify less evident nuisance compounds

Compounds that exhibit assay interference or undesirable mechanisms of bioactivity are routinely encountered in assays at various stages of drug discovery. We observed that assays for the investigation of thiol-reactive and redox-active compounds have not been collected in a comprehensive review. Here, we review these assays and subject them to experimental optimization to improve their reliability. We demonstrate the usefulness of our assay cascade by assaying a library of bioactive compounds, chemical probes, and a set of approved drugs. These high-throughput assays should complement the array of wet-lab and in silico assays during the initial stages of hit discovery campaigns to pursue only hit compounds with tractable mechanisms of action.     

白塞病诊治进展

白塞病 （Beh?et syndrome，BS）是一种少见的慢性全身性血管炎症性疾病，主要表现为复发性口腔溃疡、生殖器溃疡、皮肤及眼部损害。文章结合国内外相关指南，全面论述BS的发病机制、临床表现、诊断及鉴别诊断、治疗推荐及预后。