含par位点的重组质粒Psjm3的构建及其稳定性研究

利用自然质粒pSC101par位点的分离稳定性功能,构建了含par位点的质粒pSJM4和pSJM3,通过在同样宿主E.coli HB101中的稳定性比较研究表明,不含par位点的重组质粒pSJ3很不稳定,E.coli G3(pSJ3)在培养到第10代时已开始出现pSJ3的丢失,到培养至50代时则已全部丢失;而含par位点的重组质粒pSJM3则表现得十分稳定,E.coli G3-1(pSJM3)经70代培养,仍无明显的质粒丢失现象,其稳定率保持97%以上。通过对不含par和含par的非重组质粒pUC18和pSJM4的稳定性比较也获得同样的结果。通过对E.coliG3(pSJ3)和E.coli G3-1(pSJM3)的产酶活性比较研究表明,G3-1菌株明显高于G3菌株,说明我们构建的重组质粒pSJM3上的par位点功能不仅没有因外源基因的表达而受影响,而且有利于外源基因的表达。     

Incorporation of quantum dots on virus in polycationic solution

Developing methods to label viruses with fluorescent moieties has its merits in elucidating viral infection mechanisms and exploring novel antiviral therapeutics. Fluorescent quantum dots (QDs), an emerging probe for biological imaging and medical diagnostics, were employed in this study to tag retrovirus encoding enhanced green fluorescent protein (EGFP) genes. Electrostatic repulsion forces generated from both negatively charged retrovirus and QDs were neutralized by cationic Polybrene, forming colloidal complexes of QDs-virus. By examining the level of EGFP expression in 3T3 fibroblast cells treated with QDs-tagged retroviruses for 24 hours, the infectivity of retrovirus incorporated with QDs was shown to be only slightly decreased. Moreover, the imaging of QDs can be detected in the cellular milieu. In summary, the mild method developed here makes QDs-tagged virus a potential imaging probe for direct tracking the infection process and monitoring distribution of viral particles in infected cells.     

Study on biomolecules in extractives of Camellia oleifera fruit shell by GC–MS

This study aims to present an integrated process that can be used to produce biomedical and biological active components from the fruit shell of Camellia oleifera Abel. Through the Foss method, Aldehyde, acid compounds, acyl and alcohol compounds account for 22.7, 15.93, 0.24 and 61.13% of the extractives which were extracted from Camellia oleifera fruit shell by methanol solvents. Furfural, Pyrazole-4-carboxaldehyde, 1-methyl- and 5-Hydroxymethylfurfural account for 4.74, 1.22 and 58.78% of the extractives which were extracted from the fruit shell of Camellia oleifera Abel by ethanol solvents. Aldehyde, acid and amine compounds account for 5.01, 56.18 and 7.20% of the extractives which were extracted from the fruit shell of Camellia oleifera Abel by ethyl acetate solvents. The extractives of fresh flesh of bayberry were rich in rare drug, biomedical and biological activities.     

rh-BNP联合阿托伐他汀治疗急性心梗后心衰的临床疗效及对患者血清cTn-I、Myo、CK-MB水平的影响

目的:研究重组人脑利钠肽(rh-BNP)联合阿托伐他汀治疗急性心梗后心衰的临床效果及对患者血清心肌肌钙蛋白(cardiac troponin,cTn-I)、肌红蛋白(Myoglobin,Myo)、肌酸激酶同工酶(CK-MB)水平的影响。方法:选择我院2017年2月～2019年1月收治的72例急性心梗后心衰患者,按随机数字表法分为观察组38例,对照组34例。对照组给予阿托伐他汀治疗,观察组在对照组基础上另加rh-BNP,观察和比较两组的临床疗效,治疗前后血清cTn-I、Myo、CK-MB水平的变化及治疗后不良反应的发生情况。结果:治疗后,观察组总有效率明显高于对照组(P0.05),血清cTn-I、Myo、CK-MB水平均显著低于对照组[(0.23±0.10) vs.(0.16±0.08)、(27.54±3.86) vs.(21.62±2.54)、(70.82±9.25) vs.(61.28±8.33)](P0.05)。观察组治疗后不良反情况总发生率为7.89%,明显低于对照组(26.47%,P0.05)。结论:与单用阿托伐他汀治疗相比,静脉注射rh-BNP联合阿托伐他汀治疗急性心梗后心衰可显著提高临床疗效和安全性,有效减低血清cTn-I、Myo、CK-MB水平。     

The bracts of the alpine ‘glasshouse’ plant Rheum alexandrae (Polygonaceae) enhance reproductive fitness of its pollinating seed‐consuming mutualist

Environmental conditions are known to affect the reproductive fitness of insects, as do host plants. Although the highly specialized bracts of Himalayan ‘glasshouse’ plants are thought to be an adaptive morphology that allows the plant to reproduce in harsh alpine environments, little information appears to exist concerning the benefit of these bracts for the pollinating insects. In this study, we examine whether the semi‐translucent bracts of Rheum alexandrae, a giant herb endemic to the alpine zone of the Hengduan Mountains in south‐western China, enhance the reproductive fitness of its pollinator. Rheum alexandrae depends mainly on mutualistic seed‐consuming Bradysia flies for pollination. Bracts increased interior temperature on sunny days, acted as a buffer against fluctuating air humidity, greatly decreased the intensities of ultraviolet B/C radiation and provided shelter from strong winds. Bract removal significantly decreased adult oviposition and offspring performance of pollinators during flowering and fruiting, respectively. Our results indicate that the bracts of R. alexandrae enhance the reproductive fitness of its pollinating seed‐consuming mutualist in alpine environments, which may be attributed to the positive effects of the bracts on the interior microenvironment. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 349–359.