毛白杨悬浮细胞系的建立及再生植株的获得

以毛白杨基因型TC152无菌苗为材料,研究毛白杨悬浮细胞系建立与植株再生,结果表明,通过悬浮培养和固体培养两种方法诱导毛白杨悬浮细胞分化不定芽,最终获得无菌生根苗。愈伤组织在MS＋1.5mg·L-12,4-D＋30g·L-1蔗糖的液体培养基中振荡培养,12d可建立悬浮细胞系;悬浮细胞系继代培养基为MS＋0.8mg·L-12,4-D＋30g·L-1蔗糖,继代周期为7d,悬浮细胞在MS＋1.0mg·L-16-BA＋0.1mg·L-1NAA＋0.5～1.0mg·L-1ZT＋30g·L-1蔗糖培养基中悬浮培养,可分化大量不定芽,每个培养瓶中可得到40～50个芽,个别不定芽玻璃化;不定芽在1/2MS＋0.6mg·L-1IBA＋20g·L-1蔗糖＋5.5g·L-1琼脂培养基上可分化不定根。悬浮细胞通过固体平板培养增殖为愈伤组织块后,在MS＋1.0mg·L-16-BA＋0.1mg·L-1NAA＋1.0mg·L-1ZT＋30g·L-1蔗糖＋5g·L-1琼脂的固体培养基上,不定芽分化率可达到70.00%。     

瑞舒伐他汀对载脂蛋白E基因敲除小鼠动脉粥样硬化中调节性T细胞的影响

目的：探讨瑞舒伐他汀对载脂蛋白E基因敲除（ApoEKO）小鼠动脉粥样硬化中调节性T细胞的影响。方法：首先将30只ApoEKO小鼠建立动脉粥样硬化模型,随机分为高胆固醇饮食组（对照组）、瑞舒伐他汀低剂量组和瑞舒伐他汀高剂量组,各组分别给予蒸馏水或瑞舒伐他汀进行干预8周;将主动脉根部行冰冻切片油红染色,评估粥样硬化斑块面积大小;免疫组织化学法检测主动脉根部粥样硬化斑块处调节性T细胞（Treg）的表达。结果：各组小鼠均有动脉粥样硬化斑块形成,采用瑞舒伐他汀治疗的小鼠动脉粥样硬化斑块的面积明显小于未经治疗的小鼠（P〈0.01）,同时瑞舒伐他汀能明显增加粥样硬化病变处调节性T细胞的表达,且呈现剂效关系。结论：本实验观察到瑞舒伐他汀不仅能减小ApoEKO小鼠的主动脉粥样硬化斑块,且能使调节性T细胞的表达增多,推测瑞舒伐他汀可以通过促进调节性T细胞的生成而起到抑制动脉粥样硬化的作用。     

重新评价G-480位点变异对Ⅰ型脊髓灰质炎疫苗病毒神经毒力的影响

在对分离于中国贵州省的9株Ⅰ型循环的疫苗衍生脊髓灰质炎病毒（cVDPVs）进行全基因组核苷酸序列分析后,发现已知最重要的决定病毒神经毒力的位点G-480和U-525并没有发生回复野生型突变;另外一些已知的神经毒力决定位点,如A-2438、A-2795、C-6203和G-7441等均已经发生了回复野生型突变。根据核苷酸序列的不同,从9株Ⅰ型cVDPVs毒株中选取5株病毒感染转人脊髓灰质炎病毒受体基因的小鼠进行神经毒力实验,发现它们的神经毒力都有所升高,其中CHN8184株和CHN8229-1．1株的神经毒力已经十分接近P1／Mahoney株,CHN8229-1．1株、CHN8229-2株和CHN8229-3株神经毒力依次递减,但仍处于较高水平,在它们的全基因组中分别只有7个和2个核苷酸的差异,而毒力却相差很多,提示有新的未鉴别的神经毒力决定位点的存在。对这些毒株5′非编码区（5′NCR）的第Ⅴ结构域进行二级结构预测,发现它们的二级结构很稳定。在G-480位点没有发生回复突变的情况下,部分毒株的神经毒力已经非常接近P1／Mahoney的水平,提示先前的研究中关于G-480突变对Ⅰ型脊髓灰质炎病毒神经毒力的作用可能被估计过高,G-480位点不是唯一重要的神经毒力决定位点,可能多个核苷酸联合突变才能达到减毒的效果。要真正全面了解P1／Sabin株的减毒机制,还需要进行更加深入的研究。     

NO在植物生长发育和环境胁迫响应中的作用

一氧化氮(NO)是具有生物活性和信号转导作用的气体活性分子,它不仅对植物的许多生命活动如种子萌发、生长和衰老等具有直接的生理调节功能,而且作为防御反应中的关键信使,参与了植物对外界环境胁迫的响应,如干旱胁迫、热胁迫、盐胁迫、UV-B辐射、臭氧胁迫、重金属胁迫、机械损伤以及植物抗病反应。NO与各种激素如乙烯、脱落酸、水杨酸、生长素和细胞分裂素等,在调节植物的生理活动与信号转导方面有明显的协同作用,通过激素起作用可能是植物内源NO作用的机理之一。探明在正常生长状况下植物内源NO对植物生长发育的调控机制及其参与信号转导的生理机制是目前研究的重点。     

太子参红外指纹图谱的双指标序列分析

本文采用傅里叶变换红外光谱仪测定了四大种植主产区(安徽、江苏、福建、贵州)的栽培品及河南的野生品,共13个批次太子参甲醇提取物,获得不同产地太子参栽培品的FTIR指纹图谱,并对指纹图谱进行了相似度的计算,同时结合(共有峰率,变异峰率)双指标序列分析方法,对不同产地太子参的FTIR光谱进行了研究。结果表明,该方法所建立的太子参FTIR指纹图谱能够区分栽培品和野生品的差异,双指标序列分析法能够为产区间和产区内太子参品质差异提供参考,两种分析方法结合可为该药材的质量分析、评价与控制提供依据。     

Natural variants of the human papillomavirus type 16 E6 protein differ in their abilities to alter keratinocyte differentiation and to induce p53 degradation.

Three naturally occurring variant human papillomavirus type 16 (HPV-16) E6 proteins, which contained amino acid substitutions predominantly near the N terminus, exhibited significant differences in their abilities to abrogate keratinocyte differentiation in response to serum and calcium and to induce the degradation of p53 in vitro. One variant surpassed the reference E6 protein in its ability to abrogate keratinocyte differentiation responses, whereas another showed a reduction in this activity. Interestingly, the biological activities of the HPV-16 E6 proteins and their abilities to induce p53 degradation in vitro were directly correlated. These results demonstrate that naturally occurring variants of HPV-16 differ in biological and biochemical properties which might result in differences in pathogenicity.     

过氧化氢对蚕豆气孔运动和质膜K+通道的影响

不同浓度H2O2可使蚕豆(ViciafabaL.)叶片气孔关闭,抑制气孔张开,10mmol/L的H2O2最有效,10μmol/L的H2O2仍明显使气孔关闭。且10μmol/L的H2O2抑制气孔张开作用能被EGTA所消除,表明Ca2+参与低浓度H2O2使气孔关闭的过程。2mmol/L的H2O2可使质膜内向K+通道电流明显减小,而外向K+通道电流显著增加。因此,H2O2促进蚕豆气孔关闭主要是通过抑制K+通过保卫细胞质膜内向流入,或加强K+外向流出实现的。     

Comparative investigation on spindle behavior and MPF activity changes during oocyte maturation between gynogenetic and amphimictic crucian carp

The spindle behavior and MPF activity changes in the progression of oocyte maturation were investigated and compared with cytological observation and kinase assay between gynogenetic silver crucian carp and amphimictic colored crucian carp.MPF activity was measured by using histone H1 as phosphorylation substrate.There were two similar oscillatory MPF kinase activity changes during oocyte maturation in two kinds of fishes with different reproductive modes,but there existed some subtle difference between them.The subtle difference was that the first peak of MPF kinase activity was kept to a longerlasting time in the gynogenetic silver crucian carp than in the amphimictic colored crucian carp.It was suggested that the difference may be related to the spindle behavior changes,such as tripolar spindle formation and spindle rearrangement in the gynogenetic crucian carp.     

肥大细胞在肿瘤发生发展中的作用

肥大细胞是人体主要免疫细胞之一,因其作为导致过敏反应发生的最直接效应细胞而著称.肥大细胞最主要的结构特征为其胞内含有大量嗜碱性颗粒,该颗粒内又富含种类众多的生物活性物质,包括组胺、血管内皮生长因子(vascular endothelial growth factor,VEGF)、成纤维细胞生长因子(fibroblast...     

A comprehensive aerobiological study of the airborne pollen in the Irish environment

Respiratory allergies triggered by pollen allergens represent a significant health concern to the Irish public. Up to now, Ireland has largely refrained from participating in long-term aerobiological studies. Recently, pollen monitoring has commenced in several sampling locations around Ireland. The first results of the pollen monitoring campaigns for Dublin (urban) and Carlow (rural) concerning the period 2017–2019 and 2018–2019, respectively, are presented herein. Additional unpublished pollen data from 1978–1980 and, 2010–2011 were also incorporated in creating the first pollen calendar for Dublin. During the monitoring period over 60 pollen types were identified with an average Annual Pollen Integral (APIn) of 32,217 Pollen × day/m³ for Dublin and 78,411 Pollen × day/m³ for Carlow. The most prevalent pollen types in Dublin were: Poaceae (32%), Urticaceae (29%), Cupressaceae/Taxaceae (11%), Betula (10%), Quercus (4%), Pinus (3%), Fraxinus (2%), Alnus (2%) and Platanus (1%). The predominant pollen types in Carlow were identified as Poaceae (70%), Urticaceae (12%), Betula (10%), Quercus (2%), Fraxinus (1%) and Pinus (1%). These prevalent pollen types increased in annual pollen concentration in both locations from 2018 to 2019 except for Fraxinus. Although higher pollen concentrations were observed for the Carlow (rural) site a greater variety of pollen types were identified for the Dublin (urban) site. The general annual trend in the pollen season began with the release of tree pollen in early spring, followed by the release of grass and herbaceous pollen which dominated the summer months with the annual pollen season coming to an end in October. This behaviour was illustrated for 21 different pollen types in the Dublin pollen calendar. The correlation between ambient pollen concentration and meteorological parameters was also examined and differed greatly depending on the location and study year. A striking feature was a substantial fraction of the recorded pollen sampled in Dublin did not correlate with the prevailing wind directions. However, using non-parametric wind regression, specific source regions could be determined such as Alnus originating from the Southeast, Betula originating from the East and Poaceae originating from the Southwest.