Pollen size strongly correlates with stigma depth among Pedicularis species

Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a positive relationship between pollen size and style length.Five floral traits were observed to be correlated among42 bumblebee-pollinated Pedicularis species(Orobanchaceae) in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin's functional hypothesis between pollen size and stigma depth.     

Leaf vein fraction influences the Péclet effect and 18O enrichment in leaf water

The process of evaporation results in the fractionation of water isotopes such that the lighter ¹⁶O isotope preferentially escapes the gas phase leaving the heavier ¹⁸O isotope to accumulate at the sites of evaporation. This applies to transpiration from a leaf with the degree of fractionation dependent on a number of environmental and physiological factors that are well understood. Nevertheless, the ¹⁸O enrichment of bulk leaf water is often less than that predicted for the sites of evaporation. The advection of less enriched water in the transpiration stream has been suggested to limit the back diffusion of enriched evaporative site water (Péclet effect); however, evidence for this effect has been varied. In sampling across a range of species with different vein densities and saturated water contents, we demonstrate the importance of accounting for the relative ‘pool’ sizes of the vascular and mesophyll water for the interpretation of a Péclet effect. Further, we provide strong evidence for a Péclet signal within the xylem that if unaccounted for can lead to confounding of the estimated enrichment within the mesophyll water. This has important implications for understanding variation in the effective path length of the mesophyll and hence potentially the δ¹⁸O of organic matter.     

Platelet proteomics applied to the search for novel antiplatelet therapeutic targets

Introduction: Unwanted platelet activation is associated with numerous diseases, mainly thrombosis-related. In this context, proteomics has emerged as a novel tool with potential for drug target discovery and to scrutinize the effects of antiplatelet drugs.

Areas covered: The present review presents the main findings of platelet proteomic studies to date in the context of drug target discovery and perspectives for the future ahead. It includes data and evidences obtained from literature searches on PubMed as well as commentaries derived from the authors’ experience and opinions.

Expert commentary: Platelet proteomics applied to drug target discovery is a young field. Recent studies have shown promising data, especially in the context of coronary artery disease. However, challenges remain such as establishing definitive guidelines for blood collection and platelet isolation, essential to guarantee data reproducibility. Recent advances in quantitative platelet proteomics should lead to novel studies with higher clinical impact in the near future.     

关节置换术后抗凝药物预防深静脉血栓及相关并发症的临床研究进展

抗凝药物有助于预防全髋关节置换术和全膝关节置换术后深静脉血栓形成,临床上最常使用的传统抗凝药物如低分子肝素、华法林等可以起到很好的预防效果。目前有一类新的口服抗凝药物已经用于临床,为关节置换术后患者带来了一种更方便、安全和有效预防血栓的治疗选择。本篇综述主要针对传统抗凝药物低分子肝素及维生素K拮抗剂,直接凝血酶抑制剂达比加群,以及选择性Xa因子抑制剂利伐沙班和阿哌沙班,对迄今为止传统抗凝药物在全髋关节置换术和全膝关节置换术患者中的临床使用经验、优缺点、以及新型口服抗凝药物最新临床用药进展进行综述,为关节置换术后患者预防深静脉血栓提供用药参考。     

An ethanol extract of Ramulus mori improves blood circulation by inhibiting platelet aggregation

Inappropriate platelet aggregation can cause blood coagulation and thrombosis. In this study, the effect of an ethanol extract of Ramulus mori (ERM) on blood circulation was investigated. The antithrombotic activity of ERM on rat carotid arterial thrombosis was evaluated in vivo, and the effect of ERM on platelet aggregation and blood coagulation time was evaluated ex vivo. To evaluate the safety of ERM, its cytotoxicity to platelets and its effect on tail bleeding time were assessed; ERM was not toxic to rat platelets and did not prolong bleeding time. Moreover, administering ERM to rats had a significant preventive effect on carotid arterial thrombosis in vivo, and significantly inhibited adenosine diphosphate- and collagen-induced platelet aggregation ex vivo, whereas it did not prolong coagulation periods, such as prothrombin time and activated partial thromboplastin time. The results suggest that ERM is effective in improving blood circulation via antiplatelet activity rather than anticoagulation activity.     

急性冠脉综合征患者NLR、MPV与Gensini评分的相关性分析

目的:探讨急性冠脉综合征(Acute Coronary Syndrome,ACS)患者的中性粒细胞/淋巴细胞(Neutrophils/lymphocyte,NLR)、平均血小板体积(Mean platelet volume,MPV)与Gensini评分的相关性。方法:将156例ACS患者依据冠状动脉造影结果分为单支病变组、双支病变组及三支病变组,比较各组间NLR、MPV、Gensini评分及一般临床资料,并分析不同指标之间的相关性。结果:与双支病变组、单支病变组相比较,三支病变组吸烟、糖尿病、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)、尿酸(uric acid,UA)、NLR、MPV、Gensini评分均显著升高(P0.05);与单支病变组相比较,双支病变组吸烟、糖尿病、LDL-C、HDL-C、UA、NLR、MPV、Gensini评分均显著升高(P0.05);三组间年龄、性别、高血压、总胆固醇(total cholesterol,TC)、甘油三酯(triglyceride,TG)、肌酐(creatinine,Cr)比较差异均无统计学意义(P0.05)。Pearson相关性分析表明:NLR、MPV与Gensini评分均呈正相关(r=0.482、0.702, P0.05)。结论:ACS患者MPV和NLR与冠状动脉病变程度呈显著正相关,可有效评估冠状动脉狭窄程度。     

血清sTREM-1、肺功能指数与肺癌患者术后肺部感染的关系及其预测价值研究

目的:探讨血清髓样细胞触发受体-1(sTREM-1)、肺功能指数与肺癌患者术后肺部感染的关系及其预测价值。方法:回顾性分析2016年1月-2019年1月在我院进行手术治疗的115例肺癌患者的临床资料,根据患者术后72 h是否发生肺部感染将其分为感染组(n=28)及未感染组(n=87)。对比两组患者临床资料、术后6 h血清s TREM-1、降钙素原(PCT)水平及术前肺功能指数[第一秒用力呼气量(FEV1)、呼气流量峰值(PEF)]变化,记录感染组患者痰细菌培养结果,采用Logistic分析肺癌患者术后感染的影响因素,并采用受试者工作特征(ROC)曲线分析s TREM-1、FEV1、PEF在肺癌术后感染的预测价值。结果:感染组术后入住ICU比例大于未感染组,感染组TNM分期为IV期的比例大于未感染组(P0.05),感染组术后6 h血清s TREM-1、PCT水平高于未感染组,术前FEV1、PEF水平低于未感染组(P0.05)。感染组痰培养结果提示G-菌为17例,占60.71%;G+菌10例,占35.71%;真菌1例,占3.57%。二元多因素Logistic分析提示术后6 h血清s TREM-1水平升高、术前FEV1下降及PEF下降、术后入住ICU为肺癌患者术后感染的独立影响因素。三者联合预测曲线下面积为0.850(95%CI:1.350～1.745,P=0.000),敏感度与特异性分别为91.3%与80.6%,优于s TREM-1、FEV1、PEF的单独预测效能。结论:s TREM-1水平升高,术前FEV1、PEF水平降低与肺癌患者术后肺部感染密切相关,对s TREM-1、FEV1、PEF三者联合分析对于预测肺癌患者术后肺部感染的发生具有较高的预测价值。     

Simvastatin preparations promote PDGF‐BB secretion to repair LPS‐induced endothelial injury through the PDGFRβ/PI3K/Akt/IQGAP1 signalling pathway

Endothelial barrier dysfunction is a critical pathophysiological process of sepsis. Impaired endothelial cell migration is one of the main reasons for endothelial dysfunction. Statins may have a protective effect on endothelial barrier function. However, the effect and mechanism of statins on lipopolysaccharide (LPS)‐induced endothelial barrier dysfunction remain unclear. Simvastatin (SV) was loaded in nanostructured lipid carriers to produce SV nanoparticles (SV‐NPs). Normal SV and SV‐NPs were used to treat human umbilical vein vascular endothelial cells (HUVECs) injured by LPS. Barrier function was evaluated by monitoring cell monolayer permeability and transendothelial electrical resistance, and cell migration ability was measured by a wound healing assay. LY294002 and imatinib were used to inhibit the activity of PI3K/Akt and platelet‐derived growth factor receptor (PDGFR) β. IQ‐GTPase‐activating protein 1 (IQGAP1) siRNA was used to knockdown endogenous IQGAP1, which was used to verify the role of the PDGFRβ/PI3K/Akt/IQGAP1 pathway in SV/SV‐NPs‐mediated barrier protection in HUVECs injured by LPS. The results show that SV/SV‐NPs promoted the migration and decreased the permeability of HUVECs treated with LPS, and the efficacy of the SV‐NPs exceeded that of SV significantly. LY294002, imatinib and IQGAP1 siRNA all suppressed the barrier protection of SV/SV‐NPs. SV/SV‐NPs promoted the secretion of platelet‐derived growth factor‐BB (PDGF‐BB) and activated the PDGFRβ/PI3K/Akt/IQGAP1 pathway. SV preparations restored endothelial barrier function by restoring endothelial cell migration, which is involved in the regulation of the PDGFRβ/PI3K/Akt/IQGAP1 pathway and PDGF‐BB secretion. As an appropriate formulation for restoring endothelial dysfunction, SV‐NPs may be more effective than SV.     

Evolution of ASPM coding variation in apes and associations with brain structure in chimpanzees

Studying genetic mechanisms underlying primate brain morphology can provide insight into the evolution of human brain structure and cognition. In humans, loss‐of‐function mutations in the gene coding for ASPM (Abnormal Spindle Microtubule Assembly) have been associated with primary microcephaly, which is defined by a significantly reduced brain volume, intellectual disability and delayed development. However, less is known about the effects of common ASPM variation in humans and other primates. In this study, we characterized the degree of coding variation at ASPM in a large sample of chimpanzees (N = 241), and examined potential associations between genotype and various measures of brain morphology. We identified and genotyped five non‐synonymous polymorphisms in exons 3 (V588G), 18 (Q2772K, K2796E, C2811Y) and 27 (I3427V). Using T1‐weighted magnetic resonance imaging of brains, we measured total brain volume, cerebral gray and white matter volume, cerebral ventricular volume, and cortical surface area in the same chimpanzees. We found a potential association between ASPM V588G genotype and cerebral ventricular volume but not with the other measures. Additionally, we found that chimpanzee, bonobo, and human lineages each independently show a signature of accelerated ASPM protein evolution. Overall, our results suggest the potential effects of ASPM variation on cerebral cortical development, and emphasize the need for further functional studies. These results are the first evidence suggesting ASPM variation might play a role in shaping natural variation in brain structure in nonhuman primates.