陕南寒武系下部宽川铺组帽球状化石*

陕南寒武纪早期宽川铺组微体球状化石类型多样,如何正确辨别这些球状化石的生物属性是当前早期生命演化古生物学研究中的一个难点。我们在宽川铺组中发现了一类为数众多,具有一个或者多个不规则的帽状隆起结构以及翻边帽沿的帽状化石。研究表明这些帽状化石均为不完整的个体,其完整形态呈不规则的凹球形。根据帽球状化石帽身的数量和相对位置,这类化石可划分为"单帽型"、"双帽型"和"复帽型"三种类型。这些凹球状化石呈双层壳壁,内壁光滑,外壁粗糙。因为凹球状化石形态及其表面小孔与微体藻类、后生动物的胚胎以及壳体化石差异都非常显著,所以推测这类化石可能与带壳原生动物亲缘关系最为紧密。     

Bombyx mori prothoracicostatic peptide inhibits ecdysteroidogenesis in vivo

Bombyx prothoracicostatic peptide (Bom-PTSP) is a brain neuropeptide that has recently been reported to have in vitro inhibitory activity to prothoracicotropic hormone (PTTH)-stimulated ecdysteroid biosynthesis in the prothoracic gland of the silkworm, Bombyx mori. In the present report, Bom-PTSP has been shown to significantly decrease hemolymph ecdysteroid titer in the fifth instar larvae when Bom-PTSP was injected into the fifth instar day 8 silkworm larvae, resulting in significant delay in spinning behavior. This is the first evidence that Bom-PTSP inhibits in vivo ecdysteroidogenesis in the silkworm.     

酪酸梭菌与婴儿型双歧杆菌对产气荚膜梭菌试管内生物拮抗作用的研究

用酪酸权菌（Clostridium butyricum）和婴儿型双歧杆菌（Bifidobacterium Infantis）对产气荚膜梭菌（Clostriduim perfringens）进行试管内的生物拮抗试验。将酪酸梭菌、婴儿型双歧杆菌及酪酸梭菌和婴儿型双歧杆菌分别对产气荚膜酸菌以一定的比例等量混合接种于GAM液体培养基中进行厌氧培养。实验证明酪酸梭菌和婴儿型双歧能明显抑制产气荚膜梭菌的生长,并且比各自单独培养时显示了较强的生物拮抗作用。     

中国顶丝藻科（Acrochaetiaceae）新记录I

中国顶丝藻科新记录６种。密集旋体藻Ａｕｄｏｕｉｎｅｌｌｅｄｅｎｓａ,亮管旋体藻Ａ．ｈｙａｌｏｓｉｐｈｏｎｉａｅ,小旋体藻Ａ．ｐａｒｖｕｌａ,羽状旋体藻Ａ．ｐｌｕｍｏｓａ,顶生旋体藻Ａ．ｔｅｒｍｉｎａｌｉｓ,图氏旋体藻Ａ．ｔｈｕｒｅｔｉｉ。     

胡须信息在大鼠双侧初级体感皮层间的传递路径

大鼠的初级体感皮层(primary somatosensory cortex,SⅠ)虽然只接受来自对侧胡须的上行输入,但仍可以被同侧胡须刺激所激活.解剖学研究发现,在两侧SⅠ皮层之间有两条传递胡须信息胼胝体通路:一条是类颗粒区(perigranular zone,PGZ)通路;另一条是异颗粒区(dysgranular zone,DZ)通路.然而,哪一条通路在传递胡须刺激信息的过程中起主要作用还不清楚.本研究使用电压敏感染料(voltage-sensitive dye,VSD)成像技术来观察胡须刺激时整个SⅠ的神经元群体活动的空间分布和时间特性.实验发现,对侧胡须刺激首先激活barrel(颗粒区,granular zone,GZ),然后以兴奋波的形式传播到胡须感觉区(sub-barrel field cortex,BFC)外侧的DZ.而与首先激活BFC的对侧胡须刺激不同,同侧胡须刺激首先激活SⅠ的DZ.所激发的皮层兴奋以波的形式传播并扩散至BFC.失活另一侧皮层可以抑制这种同侧反应.电刺激另一侧半球皮层与刺激同侧胡须类似,也首先激活成像侧DZ.我们的实验结果显示,胡须刺激激活对侧SⅠ,在经过胼胝体传导后,另一侧半球的DZ(同侧于被刺激的胡须)被激活.连接双侧皮层DZ区的胼胝体连接在SⅠ对同侧胡须刺激的反应中起了主导作用.     

不同口径陷阱诱捕器诱杀梨小食心虫研究

梨小食心虫Grapholitha molesta(Busck)是重要的蛀果类害虫之一,目前性信息素广泛应用于梨小食心虫防治,为明确性信息素陷阱诱捕器的诱捕效果,针对开口方式设计四面开口和两面开口两种处理的陷阱诱捕器;针对口径的大小下设计2、3、4、5、6 cm的5种口径的对口瓶陷阱式诱捕器,分别在桃园对梨小食心虫进行诱捕试验,诱捕结果显示两面开口的诱捕器诱捕效果比四面开口的诱捕器效果显著,口径为2 cm和3 cm的陷井式诱捕器诱捕效果最佳,诱捕量显著高于5 cm和6 cm,诱捕量达34.6头/日和20.4头/日。通过试验明确了陷阱诱捕器的最佳诱捕效果的参数,同时为测报及田间大量诱杀的诱捕器使用提供依据,为防控梨小食心虫性信息素诱捕器提供标准化参数。     

利用网络平台辅助遗传学教学的探索与实践

随着新技术的发展, 教学方法日趋丰富。在传统的教学基础上, 网络技术为教学过程搭建了新的平台。在遗传学教学中, 应用网络平台指导学生进行学习, 为提高学生的学习兴趣和进行自主性学习提供了可能。本教研组多年的探索与应用过程表明, 网络教学是遗传学教学中有效的辅助手段之一, 具有传统教学不可比拟的优势。文章就网络教学平台的构建、网络教学的优势与不足以及相应的对策进行了介绍。     

In vivo sequence variability of human immunodeficiency virus type 1 envelope gp120: association of V2 extension with slow disease progression.

According to the rate of depletion of CD4 cell counts, we grouped 12 cases of human immunodeficiency virus type 1 (HIV-1) infection as 6 rapid (21.0 to 33.8 cells per microl per month) and 6 slow (0.9 to 7.9 cells per microl per month) progressors and determined the individual viral quasispecies patterns by sequencing the genome region encoding the V1, V2, and V3 loops of envelope protein. Although the quasispecies structures varied widely from one individual to another, a strong correlation was observed between a low rate of disease progression and a high degree of genetic diversity of HIV-1. Furthermore, the V2 loop extension was observed specifically in individuals with slow or no disease progression, whereas basic amino acid substitutions in V3 characteristic of a viral phenotype shift from non-syncytium inducing to syncytium inducing were observed in patients with advanced stages of disease regardless of their rate of disease progression. Studies with recombinant viruses suggested that elongation of V2 potentially restricts the capacity of HIV-1 to replicate in macrophages. Thus, our results suggest the association of distinct sequence features of both V3 and V2 with particular patterns of disease progression. Elongation of the V2 loop may be a good predictor of slow disease progression, while basic substitutions of V3 without elongation of V2 are characteristic of rapid progression.     

A static pressure sensitive receptor APJ promote H9c2 cardiomyocyte hypertrophy via PI3K-autophagy pathway

This study is designed to investigate whether APJ receptor acts as a sensor in static pressure-induced cardiomyocyte hypertrophy and to investigate the mechanism of PI3K- autophagy pathway. The left ventricular hypertrophy rat model was established by coarctation of abdominal aorta. H9c2 rat cardiomyocytes were cultured in the presence of static pressure which was given by a custom-made pressure in- cubator. The results revealed that the expression of apelin/ APJ system, PI3K, Akt and their phosphorylation were sig- nificantly increased in the operation group. Static pressure up-regulated the APJ expression, PI3K phosphorylation, Akt phosphorylation, LC3-Ⅱ/Ⅰ and beclin-1 expression in cardio- myocytes. APJ shRNA pGPU6/Neo-rat-399, PI3K inhibitor LY294002, Akt inhibitor 1701-1 blocked the up-regulation of APJ, PI3K phosphorylation, Akt phosphorylation, LC3-H/I and beclin-1 expression, respectively. Moreover, static pres- sure increased the diameter, volume, protein content of cells, and these could be reversed when the cells were treated with pGPU6/Neo-rat-399, LY294002, and autop- hagy inhibitor 3-methyladenine, respectively. These results suggested that static pressure up-regulates APJ expression to promote cardiomyocyte hypertrophy by a PI3K-autop- hagy pathway.