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.     

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.     

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.     

Performance evaluation of newly developed fluorescence immunoassay-based interferon-gamma release assay for the diagnosis of latent tuberculosis infection in healthcare workers

The ichroma? IGRA-TB (Boditech Med Inc., Chuncheon, Republic of Korea) is an automated fluorescent immunoassay-based point-of-care interferon-gamma release assay for detecting latent tuberculosis infection. We evaluated this assay with 408 health care workers, and demonstrated its acceptable performances comparing to QuantiFERON-TB Gold-Plus (QFT-Plus; Qiagen, Germantown, MD).     

KEYNOTE⁃799:帕博利珠单抗联合同步放化疗治疗Ⅲ期不可切除NSCLC的Ⅱ期临床研究

1文献来源Jabbour SK,Lee KH,Frost N,et al.Pembrolizumab plus concurrent chemoradiation therapy in patients with unresectable,locally advanced,stageⅢnon?small cell lung cancer.The phase 2 KEYNOTE?799 nonrandomized trial[J].JAMA Oncol,2021,7(9):1-9.     

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。     

儿童腹型过敏性紫癜不同中医证候临床及尿液蛋白质组学差异比较＊

目的 探讨儿童腹型过敏性紫癜（AHSP）不同中医证候的临床及尿液蛋白特征。方法 按照诊断及纳入、排除标准，收集AHSP不同中医证候患儿的临床信息及尿样进行分析，并通过尿液蛋白质组质谱分析，筛选及比较AHSP不同证候的尿液差异蛋白。结果 AHSP不同证候临床特征显示，皮肤紫癜首发者风热伤络证最多，湿毒内蕴证次之；皮肤紫癜伴腹痛症状首发者仅在脾虚不摄证中出现。不同证候间实验室指标未出现统计学差异。通过DDA及DIA定量方法，在不同证候间筛选出21个证候差异蛋白，其中风热伤络、湿毒内蕴证间2个，风热伤络、脾虚不摄证间3个，湿毒内蕴、脾虚不摄证间16个；经OPLS-DA分析筛选出10个差异蛋白，包括ALDOB、Glyc、GSTA2、GPDA、GAPDH、CRYL1、AK1A1、VMO1、Cat S、DHPR。结论 AHSP不同证候间临床及尿液蛋白存在差异，这些差异可为腹型过敏性紫癜的证候诊断提供一定的帮助。     

The predictive value of crescents in adult Henoch-Sch?lein purpura nephritis

Objective To study the renal prognosis with the type and proportion of crescentic in adult Henoch Schonlein purpura nephritis (HSPN). Methods A total of 275 HSPN cases diagnosed in the First Affiliated Hospital of Zhejiang University were retrospectively analyzed. According to the pathological results, they were divided into four groups: 99 patients in none crescent group (NC), 35 patients in segmental crescents group (SC), 122 patients with circumferential crescent ＜25% (C1), and 19 patients with circumferential crescent≥25% (C2). Renal prognostic events were defined as estimated glomerular filtration rate (eGFR) decreased by 30% over baseline within 2 years, doubling of serum creatinine or end-stage renal disease during follow-up. Kaplan-Meier survival analysis was used to compare the renal survival rate of each group. Univariate and multivariate Cox regression model was used to recognize the risk factor of poor renal outcome. Results There was no significant difference in age, extra renal organ performance and mean arterial pressure among groups. Among NC group, SC group, C1 group and C2 group, difference in serum creatinine (P=0.001), eGFR (P=0.003) and proteinuria levels (P＜0.001) were statistically significant. There was no significant difference in the ratio of global sclerosis, mesangial hypercellularity and interstitial inflammation/fibrosis among the groups. The patients were followed up for 86(58, 116) months. The renal survival rates of NC group, SC group, C1 group and C2 group were 96%, 100%, 83.6% and 68.4% respectively. Kaplan-meier survival analysis showed significant differences (Log Rank=23.24, P＜0.001). Cox multivariate regression analysis indicated that presence of circumferential crescent (HR=3.59, 95%CI 1.34-9.62, P=0.008) and low eGFR (HR=0.979, 95%CI 0.968-0.989, P＜0.001) were independent prognostic factors. Conclusion The presence of circumferential crescent and low eGFR level are independent risk factors for poor renal prognosis in HSPN patients.