洛阳地区黄胸木蜂采访丹参的访花行为研究

在洛阳地区丹参Salvia miltiorrhiza的盛花期5月上中旬,采用目测、拍照、测量等方法记录丹参花的基本特征、黄胸木蜂Xylocopa appendiculata的访花行为、丹参被盗蜜后盗蜜口的大小和盗蜜率。在洛阳地区,黄胸木蜂是丹参的主要访花者,在对丹参进行访花时,多盗取花蜜。黄胸木蜂访花时,其单花停留时间平均为3.81±0.28 s,两花间隔时间的平均值为3.64±1.94 s,访花频率的平均值为每分钟采访的花朵数为6±0.98朵,访花朵数为6时,访花频率最大。黄胸木蜂在丹参上的盗蜜口的大小的平均值为0.304±0.046 cm,盗蜜率平均为37%±12%。黄胸木蜂对丹参的盗蜜现象普遍存在,且重复盗蜜,有的一朵花上可能有多个盗蜜口,其盗蜜行为对丹参繁殖适合度的影响还有待进一步研究。本文对黄胸木蜂采访丹参的访花行为进行研究,旨在为进一步开发和利用木蜂资源奠定基础。     

Studying the Effects of Reproductive Hormones and Bacterial Vaginosis on the Glycome of Lavage Samples from the Cervicovaginal Cavity

The cervicovaginal fluid (CVF) coating the vaginal epithelium is an important immunological mediator, providing a barrier to infection. Glycosylation of CVF proteins, such as mucins, IgG and S-IgA, plays a critical role in their immunological functions. Although multiple factors, such as hormones and microflora, may influence glycosylation of the CVF, few studies have examined their impact on this important immunological fluid. Herein we analyzed the glycosylation of cervicovaginal lavage (CVL) samples collected from 165 women under different hormonal conditions including: (1) no contraceptive, post-menopausal, (2) no contraceptive, days 1-14 of the menstrual cycle, (3) no contraceptive, days 15-28 of the menstrual cycle, (4) combined-oral contraceptive pills for at least 6 months, (5) depo-medroxyprogesterone acetate (Depo-Provera) injections for at least 6 months, (6) levonorgestrel IUD for at least 1 month. Glycomic profiling was obtained using our lectin microarray system, a rapid method to analyze carbohydrate composition. Although some small effects were observed due to hormone levels, the major influence on the glycome was the presence of an altered bacterial cohort due to bacterial vaginosis (BV). Compared to normal women, samples from women with BV contained lower levels of sialic acid and high-mannose glycans in their CVL. The change in high mannose levels was unexpected and may be related to the increased risk of HIV-infection observed in women with BV, as high mannose receptors are a viral entry pathway. Changes in the glycome were also observed with hormonal contraceptive use, in a contraceptive-dependent manner. Overall, microflora had a greater impact on the glycome than hormonal levels, and both of these effects should be more closely examined in future studies given the importance of glycans in the innate immune system.     

Nutritional Energy Stimulates NAD+ Production to Promote Tankyrase-Mediated PARsylation in Insulinoma Cells

The poly-ADP-ribosylation (PARsylation) activity of tankyrase (TNKS) regulates diverse physiological processes including energy metabolism and wnt/β-catenin signaling. This TNKS activity uses NAD⁺ as a co-substrate to post-translationally modify various acceptor proteins including TNKS itself. PARsylation by TNKS often tags the acceptors for ubiquitination and proteasomal degradation. Whether this TNKS activity is regulated by physiological changes in NAD⁺ levels or, more broadly, in cellular energy charge has not been investigated. Because the NAD⁺ biosynthetic enzyme nicotinamide phosphoribosyltransferase (NAMPT) in vitro is robustly potentiated by ATP, we hypothesized that nutritional energy might stimulate cellular NAMPT to produce NAD⁺ and thereby augment TNKS catalysis. Using insulin-secreting cells as a model, we showed that glucose indeed stimulates the autoPARsylation of TNKS and consequently its turnover by the ubiquitin-proteasomal system. This glucose effect on TNKS is mediated primarily by NAD⁺ since it is mirrored by the NAD⁺ precursor nicotinamide mononucleotide (NMN), and is blunted by the NAMPT inhibitor FK866. The TNKS-destabilizing effect of glucose is shared by other metabolic fuels including pyruvate and amino acids. NAD⁺ flux analysis showed that glucose and nutrients, by increasing ATP, stimulate NAMPT-mediated NAD⁺ production to expand NAD⁺ stores. Collectively our data uncover a metabolic pathway whereby nutritional energy augments NAD⁺ production to drive the PARsylating activity of TNKS, leading to autoPARsylation-dependent degradation of the TNKS protein. The modulation of TNKS catalytic activity and protein abundance by cellular energy charge could potentially impose a nutritional control on the many processes that TNKS regulates through PARsylation. More broadly, the stimulation of NAD⁺ production by ATP suggests that nutritional energy may enhance the functions of other NAD⁺-driven enzymes including sirtuins.     

急性髓系白血病相关基因的DNA甲基化

急性髓系白血病(acute myeloid leukemia,AML)是异质性造血干细胞恶性克隆性疾病,主要表现为外周血、骨髓以及其他组织中的原始细胞克隆性扩增。近年来,AML发病率呈逐年增加的趋势,对人类健康产生巨大的威胁。在不同种族及不同性别中,AML发病率及死亡率存在显著差异。AML是一种复杂疾病,与遗传突变及异常表观遗传修饰密切相关。DNA甲基化是重要的表观遗传修饰,AML相关基因的异常DNA甲基化修饰对疾病的发生发展极其重要。该文对AML相关基因的异常甲基化修饰进行了系统的作用机制分析,并对重要基因进行了功能分类。该文总结的具有异常DNA甲基化修饰的基因,有望辅助预测AML的治疗及预后效果,并为设计个体化AML治疗方案提供全新的思路。     

Lonafarnib Is a Potential Inhibitor for Neovascularization

Atherosclerosis is a common cardiovascular disease that involves the build-up of plaque on the inner walls of the arteries. Intraplaque neovacularization has been shown to be essential in the pathogenesis of atherosclerosis. Previous studies showed that small-molecule compounds targeting farnesyl transferase have the ability to prevent atherosclerosis in apolipoprotein E-deficient mice, but the underlying mechanism remains to be elucidated. In this study, we found that lonafarnib, a specific inhibitor of farnesyl transferase, elicits inhibitory effect on vascular endothelial capillary assembly in vitro in a dose-dependent manner. In addition, we showed that lonafarnib treatment led to a dose-dependent decrease in scratch wound closure in vitro, whereas it had little effect on endothelial cell proliferation. These data indicate that lonafarnib inhibits neovascularization via directly targeting endothelial cells and disturbing their motility. Moreover, we demonstrated that pharmacological inhibition of farnesyl transferase by lonafarnib significantly impaired centrosome reorientation toward the leading edge of endothelial cells. Mechanistically, we found that the catalytic β subunit of farnesyl transferase associated with a cytoskeletal protein important for the establishment and maintenance of cell polarity. Additionally, we showed that lonafarnib remarkably inhibited the expression of the cytoskeletal protein and interrupted its interaction with farnesyl transferase. Our findings thus offer novel mechanistic insight into the protective effect of farnesyl transferase inhibitors on atherosclerosis and provide encouraging evidence for the potential use of this group of agents in inhibiting plaque neovascularization.     

苜蓿夜蛾保幼激素酯酶cDNA的克隆、序列分析及表达研究

【目的】研究苜蓿夜蛾Heliothis viriplaca保幼激素酯酶(Juvenile hormone esterase,JHE)的功能和作用机理。【方法】本试验提取苜蓿夜蛾的总RNA,并利用RT-PCR和RACE技术,扩增得到苜蓿夜蛾保幼激素酯酶基因的全长c DNA序列,命名为Hvjhe(Gen Bank登录号:JQ901384)。【结果】该基因含有3 106 bp,包括一个1 746 bp的开放阅读框,编码一个含581个氨基酸的多肽,分子量约为63.9 ku,多肽的等电点为5.11,且氨基酸序列具含有5个保幼激素酯酶特有的氨基酸保守模块。推导的氨基酸序列与烟芽夜蛾Heliothis virescens和棉铃虫Helicoverpa armigera中获得的保幼激素酯酶相似性较高,分别达到83%和82%。荧光定量PCR结果表明,该基因在苜蓿夜蛾不同发育时期和不同组织中都有m RNA水平的特异性表达,且在预蛹期表达量相对较高,取食期、蛹期期和成虫期表达量相对较低;在中肠和脂肪体内的表达量相对于其它组织较高。该基因在大肠杆菌Escherich coli表达系统中进行了诱导表达,经SDS-PAGE和Western blot检测结果表明,表达出与预测的蛋白分子量相符的融合蛋白。【结论】研究结果表明本试验获得了苜蓿夜蛾中一个新的保幼激素酯酶基因的c DNA序列。     

柑橘大实蝇生物、生态学及辐照不育技术最新研究进展

柑橘大实蝇是柑橘类果树的一种重要害虫,近几年在我国柑橘种植区的危害呈上升趋势,给柑橘产业造成了巨大损失。本文概述了环境因素包括温度、光周期、营养状况(饥渴)以及水淹对柑橘大实蝇生物学特性和成虫行为的影响,柑橘大实蝇成虫和幼虫人工饲养技术参数,柑橘大实蝇蛹滞育机制,辐照不育关键技术包括最佳辐照剂量和辐照时期,及其在湖北柑橘园柑橘大实蝇防控中的应用与示范情况等,并指出了尚需进一步开展的研究内容。     

不同产地丁香挥发性成分分析

采用顶空固相微萃取-气相色谱-质谱联用技术对产自国内外4个地区的丁香(Eugenia caryophyllata Thunb.)挥发性成分进行了检测,并以峰面积归一化法计算了各组分的相对含量。结果显示,从4个产地13批次丁香中共鉴定出挥发性成分72种(匹配度均高于75),其中,主要成分含量排名前两位的均为丁香酚、(-)-α-芹子烯,排名第三位的挥发性成分分别为:顺式-α-没药烯(马达加斯加塔马塔夫,平均为3.75%)、罗勒烯(中国广东,平均为4.21%)、亚麻三烯(中国广西,平均为3.74%)、丁香烯(印度尼西亚爪哇岛,平均为3.60%)。表明同一产地的丁香挥发性成分具有一定的相似性,不同产地丁香挥发性成分也有一定的差异,这对丁香产地的鉴别具有重要意义。主成分分析和聚类分析的结果既可以将4个产地的丁香很好地区分开来,又能反映出它们之间的亲缘关系。本研究采用HS-SPME-GC-MS方法检测不同产地丁香挥发性成分并结合主成分分析(PCA)及聚类分析法,能有效区分4个产地的丁香,该方法可作为丁香产地的鉴别方法,也为进一步比较不同产地丁香挥发性成分的差异及质量控制提供了新思路。     

Combined Salvianolic Acid B and Ginsenoside Rg1 Exerts Cardioprotection against Ischemia/Reperfusion Injury in Rats

Lack of pharmacological strategies in clinics restricts the patient prognosis with myocardial ischemia/reperfusion (I/R) injury. The aim of this study was to evaluate the cardioprotection of combined salvianolic acid B (SalB) and ginsenoside Rg1 (Rg1) against myocardial I/R injury and further investigate the underlying mechanism. I/R injury was induced by coronary artery ligation for Wistar male rats and hypoxia/reoxygenation injury was induced on H9c2 cells. Firstly, the best ratio between SalB and Rg1was set as 2:5 based on their effects on heart function detected by hemodynamic measurement. Then SalB-Rg1 (2:5) was found to maintain mitochondrial membrane potential and resist apoptosis and necrosis in H9c2 cell with hypoxia/reoxygenation injury. Companying with same dose of SalB or Rg1 only, SalB-Rg1 showed more significant effects on down-regulation of myocardial infarct size, maintenance of myocardium structure, improvement on cardiac function, decrease of cytokine secretion including TNF-α, IL-1β, RANTES and sVCAM-1. Finally, the SalB-Rg1 improved the viability of cardiac myocytes other than cardiac fibroblasts in rats with I/R injury using flow cytometry. Our results revealed that SalB-Rg1 was a promising strategy to prevent myocardial I/R injury.