利用电子鼻评价桃果实香气

为了明确不同桃品种资源果实香气差异,对桃果实香气评价和品质改良提供参考,本研究利用电子鼻系统对桃品种资源果实整果香气进行测定和区分.通过PEN 3.5电子鼻系统采集74份不同品种资源桃果实芳香成分并得到了不同传感器的响应值,采用主成分(PCA)、线性判别法(LDA)和负荷加载(LO)方法分析数据.LO分析结果显示,硫化...     

Ipriflavone as a non‐steroidal glucocorticoid receptor antagonist ameliorates diabetic cognitive impairment in mice

Diabetic cognitive impairment (DCI) is a common diabetic complication with hallmarks of loss of learning ability and disorders of memory and behavior. Glucocorticoid receptor (GR) dysfunction is a main reason for neuronal impairment in brain of diabetic patients. Here, we determined that ipriflavone (IP) a clinical anti‐osteoporosis drug functioned as a non‐steroidal GR antagonist and efficiently ameliorated learning and memory dysfunction in both type 1 and 2 diabetic mice. The underlying mechanism has been intensively investigated by assay against the diabetic mice with GR‐specific knockdown in the brain by injection of adeno‐associated virus (AAV)‐ePHP‐si‐GR. IP suppressed tau hyperphosphorylation through GR/PI3K/AKT/GSK3β pathway, alleviated neuronal inflammation through GR/NF‐κB/NLRP3/ASC/Caspase‐1 pathway, and protected against synaptic impairment through GR/CREB/BDNF pathway. To our knowledge, our work might be the first to expound the detailed mechanism underlying the amelioration of non‐steroidal GR antagonist on DCI‐like pathology in mice and report the potential of IP in treatment of DCI.     

GPGPU加速生物序列比对研究进展

序列比对是生物信息学中最常用和最经典的研究手段。生物序列比对需要有强大计算能力的硬件支撑,而近年快速发展起来的GPGPU正好可堪此任。本文首先介绍GPGPU的发展过程,进而讲述GPGPU硬件设备与其编程环境,然后对GPGPU做科学计算时需要的数学库函数做一介绍,最后综述近年来国内外基于GPGPU的生物序列比对软件和相关研究工作,并总结和展望其辉煌前景。     

斑马鱼转座子时空表达特性

转座子是基因组中可移动和扩展的元件,能够插入新的位点,影响基因组和基因的结构和功能,是基因组进化的内在驱动。为探讨转座子的时空表达特性,首先通过生物信息学方法鉴定出斑马鱼9个疑似活性转座子,包括DNA转座子Tc1家族(Tc-a、Tc-b、Tc-c、Tc-d、Tc-e)、反转录转座子ERV家族(ERV-1、ERV-2)和LINE家族(L1-323、L1-21),然后采用实时荧光定量PCR法检测上述转座子在斑马鱼早期胚胎发育7个阶段及成鱼各主要脏器的表达活性。结果表明:Tc1家族在0.75、2.00、3.00 h各阶段无转录活性,在6.00、15.00、24.00、48.00 h各阶段各转座子均有较高转录活性;反转录转座子转录活性最早出现于3 h,最晚出现于15 h,且随着发育时间的延长,转录活性显著增强。9种转座子在成鱼心脏、大脑、肌肉、肝脏、睾丸和卵巢均有表达,且大脑和心脏中的表达水平显著高于其他组织,睾丸表达水平最低。分析表明转座子的表达具有时间和组织的特异性,可能参与斑马鱼胚胎和组织器官发育调控,尤其是大脑和心脏发育。这些结果为进一步研究转座子是否具有基因表达调控功能提供重要参考。     

新型冠状病毒(SARS-CoV-2)蛋白靶位的生信分析

目前新型冠状病毒肺炎(COVID-19)疫情仍在全球肆虐,但尚无针对该病毒的治疗特效药.在此背景,以美国化学文摘社(Chemical Abstracts Service,CAS)提供的SARS-CoV-2病毒及宿主蛋白靶标为研究对象,运用基因功能富集、蛋白网络等方法进行生物信息分析.结果发现,人网格蛋白介导型内吞和依赖...     

蛋白质功能预测方法概述

蛋白质是生物体内最必需也是最通用的大分子,对它们功能的认识对于科学领域和农业领域的发展有着至关重要的作用。随着后基因组时代的发展,NCBI数据库中迅速涌现出大量不明结构与功能的蛋白质序列,这些蛋白质序列甚至一跃成了研究的热点。近几十年来蛋白质功能预测的方法不断被完善。由最初的仅基于蛋白质序列或3D结构信息的方法衍生出更多的基于序列相似性、基于结构基序、基于相互作用网络等新方法,这些新型方法采用新的算法、新的研究思路和技术手段,力求得到准确性与普遍性并存,能够被广泛应用的蛋白质功能预测方法。本文综述了近年来蛋白质功能预测的方法,并将这些研究方法分类归纳,各自阐明了每类方法的优缺点。     

鼠类对栓皮栎和锥栗种子的贮藏:验证高单宁假说

种子中的单宁影响鼠类的取食和贮藏策略.高单宁假说认为鼠类倾向于优先贮藏单宁含量高的种子、取食单宁含量低的种子.同域分布的鼠类对种子的取食和贮藏选择是否符合高单宁假说的预测尚缺乏足够的实验证据.本研究通过围栏实验研究了四川都江堰地区亚热带常绿阔叶林中的小泡巨鼠(Leopoldamyys edwardsi)、针毛鼠(Niv...     

Sertad1 Induces Neurological Injury after Ischemic Stroke via the CDK4/p-Rb Pathway

SERTA domain-containing protein 1 (Sertad1) is upregulated in the models of DNA damage and Alzheimer’s disease, contributing to neuronal death. However, the role and mechanism of Sertad1 in ischemic/hypoxic neurological injury remain unclear. In the present study, our results showed that the expression of Sertad1 was upregulated in a mouse middle cerebral artery occlusion and reperfusion model and in HT22 cells after oxygen-glucose deprivation/reoxygenation (OGD/R). Sertad1 knockdown significantly ameliorated ischemia-induced brain infarct volume, neurological deficits and neuronal apoptosis. In addition, it significantly ameliorated the OGD/R-induced inhibition of cell viability and apoptotic cell death in HT22 cells. Sertad1 knockdown significantly inhibited the ischemic/hypoxic-induced expression of p-Rb, B-Myb, and Bim in vivo and in vitro. However, Sertad1 overexpression significantly exacerbated the OGD/R-induced inhibition of cell viability and apoptotic cell death and p-Rb, B-Myb, and Bim expression in HT22 cells. In further studies, we demonstrated that Sertad1 directly binds to CDK4 and the CDK4 inhibitor {"type":"entrez-nucleotide","attrs":{"text":"ON123300","term_id":"2214659616"}}ON123300 restores the effects of Sertad1 overexpression on OGD/R-induced apoptotic cell death and p-Rb, B-Myb, and Bim expression in HT22 cells. These results suggested that Sertad1 contributed to ischemic/hypoxic neurological injury by activating the CDK4/p-Rb pathway.     

平原就读的藏族与汉族腹型肥胖大学生心肺功能比较研究

目的:探讨腹型肥胖对平原就读藏汉族大学生心肺功能影响的差异研究。方法:选取在校男性大学生96人,依照BMI和WC分类标准,分为藏族腹型肥胖组(TA)、藏族对照组(TC)、汉族腹型肥胖组(HA)、汉族对照组(HC)各24名。使用心脏彩色多普勒超声检查仪检测超声心动图,检测心脏结构和AV、PV、MVE、MVA、TVE、TVA等心功能指标。检测VC、FVC、FEV1、PEF、MMF、MVV等肺功能指标。检测身体形态学,血液和脂肪肝状况等基础指标。结果:腹型肥胖对血压的影响：与TC组相比,TA组SBP显著增加(P<0.01);与HC组相比,HA组SBP和DBP均显著增加(P<0.01,P<0.05)。腹型肥胖对心功能的负性影响：与TC组相比,TA组AV和PV显著减慢(P均<0.01);与HC组相比,HA组IVSA显著增大(P<0.05)。腹型肥胖对肺功能的负性影响：与TC组相比,TA组MMF和肺活量/体重水平显著降低(P<0.05);与HC组相比,HA组FEV1、FEV1%、PEF、MMF、MVV、MVV%和肺活量/体重水平均显著降低(P均<0.05)...