蛋白激酶C活性变化对Adipophilin介导THP-1巨噬细胞脂质蓄积的影响

以THP-1巨噬细胞为研究对象,观察蛋白激酶C(PKC)激动剂佛波酯(PMA)和抑制剂钙磷酸结合蛋白C(CalphostinC)对胞膜PKC活性、胞膜PKCα及胞浆内过氧化物酶体增殖物激活受体(PPARγ)和adipophilin表达以及细胞内脂质蓄积的影响,初步探讨PKC调控adipophilin表达及脂质蓄积的作用机制.采用PepTagRAssay、RT-PCR、蛋白质印迹、油红O染色和高效液相色谱法,观察到100nmol/LPMA在激活胞膜PKC((0.2514±0.0154)U/ml)的同时可以与氧化低密度脂蛋白(oxLDL)协同增强PKCα、PPARγ和adipophilin表达并使细胞内脂滴的蓄积极大地增强.细胞内胆固醇酯/总胆固醇比值增至(69.8±9.5)%;300nmol/L CalphostinC对荷脂THP-1巨噬细胞的处理则抑制酶活性至((0.0927±0.0056)U/ml,细胞内脂滴减少,胆固醇酯/总胆固醇比值降至(40.1±9.1)%;CalphostinC呈剂量依赖性的方式下调酶活性、PKCα、PPARγ和adipophilin表达,400nmol/LCalphostinC基本上可以逆转50mg/LoxLDL诱导的酶活化和PKCα、PPARγ和adipophilin表达的上调.结果提示,蛋白激酶C活性的改变可以影响adipophilin介导的脂质蓄积,其中PPARγ可能在这一调控机制中发挥了重要作用.     

Comparison of inverse-dynamics musculo-skeletal models of AL 288-1 Australopithecus afarensis and KNM-WT 15000 Homo ergaster to modern humans, with implications for the evolution of bipedalism

Size and proportions of the postcranial skeleton differ markedly between Australopithecus afarensis and Homo ergaster, and between the latter and modern Homo sapiens. This study uses computer simulations of gait in models derived from the best-known skeletons of these species (AL 288-1, Australopithecus afarensis, 3.18 million year ago) and KNM-WT 15000 (Homo ergaster, 1.5-1.8 million year ago) compared to models of adult human males and females, to estimate the required muscle power during bipedal walking, and to compare this with those in modern humans. Skeletal measurements were carried out on a cast of KNM-WT 15000, but for AL 288-1 were taken from the literature. Muscle attachments were applied to the models based on their position relative to the bone in modern humans. Joint motions and moments from experiments on human walking were input into the models to calculate muscle stress and power. The models were tested in erect walking and 'bent-hip bent-knee' gait. Calculated muscle forces were verified against EMG activity phases from experimental data, with reference to reasonable activation/force delays. Calculated muscle powers are reasonably comparable to experimentally derived metabolic values from the literature, given likely values for muscle efficiency. The results show that: 1) if evaluated by the power expenditure per unit of mass (W/kg) in walking, AL 288-1 and KNM-WT 15000 would need similar power to modern humans; however, 2) with distance-specific parameters as the criteria, AL 288-1 would require to expend relatively more muscle power (W/kg.m(-1)) in comparison to modern humans. The results imply that in the evolution of bipedalism, body proportions, for example those of KNM-WT 15000, may have evolved to obtain an effective application of muscle power to bipedal walking over a long distance, or at high speed.     

THE PEST STATUS OF BEMISIA TABACI IN CHINA AND NON‐CHEMICAL CONTROL STRATEGIES*

Abstract Bemisia tabaci (Gennadius) has been considered as a serious pest in all of tropical, subtropical and temperate regions of the world. B. tabaci first recorded as early as in 1940s in China and has been reported as a pest of various crops in 22 provinces or cities. But only recently it has become a severe problem for vegetable and ornamental crops in Guangdong and Beijing. In China B. tabaci is known to transmit at least 5 plant viruses, including tomato yellow leaf curl virus (TYLCV), tomato leaf curl virus (TomLCV), squash leaf curl virus (SqLCV‐C). So far, approximately 18 parasitoids, 17 predators and 1 pathogenic fungus were recorded in China. This paper presents an overview of B. tabaci as a pest and virus vector in China, with special attention given to non‐chemical control strategies.     

Initial hydrodynamic study on a new intraaortic axial flow pump: Dynamic aortic valve

Rotary blood pumps have been researched as implantable ventricular assist devices for years. To further reduce the complex of implanted axial pumps, the authors proposed a new concept of intraaortic axial pump, termed previously as “dynamic aortic valve (DAV)”. Instead of being driven by an intraaortic micro-electric motor, it was powered by a magnetic field from outside of body. To ensure the perfusion of coronary artery, the axial flow pump is to be implanted in the position of aortic valve. It could serve as either a blood pump or a mechanical valve depending on the power input. This research tested the feasibility of the new concept in model study. A column, made from permanent magnet, is jointed to an impeller in a concentric way to form a “rotor-impeller”. Supported by a hanging shaft cantilevered in the center of a rigid cage, the rotor-impeller can be turned by the magnetic field in the surrounding space. In the present prototype, the rotor is 8 mm in diameter and 15 mm in length, the impeller has 3 vanes with an outer diameter of 18 mm. The supporting cage is 22 mm in outer diameter and 20 mm in length. When tested, the DAV prototype is inserted into the tube of a mock circuit. The alternative magnetic field is produced by a rotating magnet placed side by side with the rotor-impeller at a distance of 30 mm. Once the alternative magnetic field is presented in the surrounding space, the DAV starts to turn, leading to a pressure difference and liquid flow in the tube. The flow rate or pressure difference is proportioned to rotary speed. At the maximal output of hydraulic power, the flow rate reached 5 L/min against an afterload of 100 mmHg. The maximal pressure difference generated by DAV at a rotation rate of 12600 r/min was 147 mmHg. The preliminary results demonstrated the feasibility of “DAV”, further research on this concept is justifiable.     

The effect of decreasing alkalinity on microbial community dynamics in a sulfate-reducing bioreactor as analyzed by PCR-SSCP

PCR-single-strand conformation polymorphism (SSCP) and Southern blotting techniques were adopted to investigate microbial community dynamics in a sulfate-reducing bioreactor caused by decreasing influent alkalinity. Experimental results indicated that the sulfate-removal rate approached 87% in 25 d under the conditions of influent alkalinity of 4000 mg/L (as CaCO₃) and sulfate-loading rate of 4.8 g/(L·d), which indicated that the bioreactor started up successfully. The analysis of microbial community structure in this stage showed that Lactococcus sp., Anaerofilum sp. and Kluyvera sp. were dominant populations. It was found that when influent alkalinity reduced to 1000 mg/L, sulfate-removal rate decreased rapidly to 35% in 3 d. Then influent alkalinity was increased to 3000 mg/L, the sulfate-removal rate rose to 55%. Under these conditions, the populations of Dysgonomonas sp., Sporobacte sp., Obesumbacterium sp. and Clostridium sp. got to rich, which predominated in the community together with Lactococcus sp., Anaerofilum sp. and Kluyvera sp. However, when the alkalinity was decreased to 1500 mg/L, the sulfate-removal rate rose to and kept stable at 70% and populations of Dysgonomonas sp., Sporobacter sp. and Obesumbacterium sp. died out, while some strains of Desulfovibrio sp. and Clostridium sp. increased in concentration. In order to determine the minimum alkalinity value that the system could tolerate, the influent alkalinity was decreased from 1500 to 400 mg/L secondly. This resulted in the sulfate-removal rate, pH value and effluent alkalinity dropping quickly. The amount of Petrotoga sp., Prevotella sp., Kluyvera sp. and Neisseria sp. reduced obviously. The result data from Southern blotting indicated that the amount of sulfate-reducing bacteria (SRBs) decreased with influent alkalinity dropping. Analysis of the microbial community structure and diversity showed that the SRBs populations were very abundant in the inoculated activated sludge and the alkalinity decrease caused the reduction of the populations noted. Most of resident populations in the bioreactor were fermentative acidogenic bacteria (FABs), among which the phylum Firmicute was in the majority, but SRBs were very few. This community structure demonstrates the cooperation between SRBs and FABs, which sustains the system’s high sulfate-removal and operation stability.     

Degradation of Pinene by Bacillus pallidus BR425

An aerobic thermophile has been isolated from an -pinene enrichment culture. The isolate, which was designated BR425, has been tentatively identified as Bacillus pallidus using 16S ribosomal RNA gene sequencing and organism morphology. Monophasic and biphasic incubations of BR425 cells with -pinene, -pinene, and limonene yielded a number of oxidized monoterpene metabolites with carveol as a common metabolite. A pinene degradation pathway with carveol and carvone as central metabolic intermediates is suggested.     

东方杯叶吸虫囊蚴的体外培养和发育的研究

本文用含小鸡血清的培养基将东方杯叶吸虫脱囊后尾蚴体外培养至怀卵成虫,但虫卵不正常。添加小鸡小肠粘膜浸出液能明显提高怀卵率和产卵量,但不影响怀卵量,41℃比37℃培养结果更好;后尾蚴的发育经历了精巢、阴茎囊、卵巢和卵黄腺的形成及怀卵和产卵的过程,体外培养中虫体发育延缓。     

基于谷歌地球引警和改进型遥感生态指数的西安市生态环境质量动态监测

近年来,在经济全球化的背景下,西安市经济迅速增长,生态环境问题日益突出,快速全面地定量监测生态环境质量的时空变化,对指导生态环境保护具有重要意义。基于谷歌地球引警(GEE)平台,筛选2000、2004、2010、2015、2020年及其前后各一年的四季Landsat影像,利用主成分分析基于绿度(NDVI)、热度(LST)、干度(NDSI)、湿度(Wet)和气溶胶光学厚度(AOD)构建改进型遥感生态指数(ARSEI),实现西安市2000—2020年生态环境质量的动态监测,并运用莫兰指数(Moran′s I)探讨西安市生态环境质量的空间自相关。以主成分效果最好的夏季为例,结果表明：(1)构建的ARSEI将大气污染因素考虑在内,第1主成分(PC1)贡献度在83%以上,能较好地集中各指标特征,有助于更加全面地评价研究区生态环境质量;(2)西安市2000—2020年平均ARSEI分别为0.565、0.521、0.572、0.644、0.695,生态环境质量总体呈现先退化后转好的趋势。20年来,生态环境质量较差和极差等级的面积减少了1339.08 km²,主要分布在秦岭以北地...     

武陵山区缘蝽科新种记述(半翅目:异翅亚目)

本文报道武陵山区缘蝽科6新种:细足赧缘蝽Ochrochira stenopoda sp.nov,武陵黑缘蝽H-ygia(Colpura)wulingana sp.nov,雅翅同缘蝽 Homoecerus(Anacanthoris)viridulus sp.nov,钩曼缘蝽Manocoreus grypidus sp.nov,四川锤缘蝽 Marcius sichuananus sp.nov.,黑刺锤缘蝽 Marcius ni-grospinosussp.nov.。     

CRISPR/Cas9技术在工业微生物中的应用

近年来,通过基因编辑技术对工业微生物底盘细胞改造从而获得的优良细胞工厂,促进了农业、医学、环境、能源等领域的可持续发展,提高了人民的生活水平。微生物底盘细胞的改造离不开基因编辑,作为现阶段主要的基因编辑技术,规律间隔成簇短回文重复序列（clustered regularly interspaced short palindromic repeats,CRISPR）/Cas9系统自被发现以来,依靠其低成本、高效率等编辑优点,被广泛用于工业微生物底盘细胞的改造。本文主要简述了以CRISPR/Cas9为基础而衍伸出的各种基因编辑技术,提出了常用的工业微生物对应底盘细胞的改造策略,以期为研究者在进行微生物底盘细胞改造时选择出合适的基因编辑方法。最后指出了CRISPR基因编辑技术面临的PAM位点的依赖性、脱靶效应和应用广泛性等问题。