New insights into the molecular mechanisms of sperm-egg interaction

At the moment of insemination millions of mammalian sperm cells are released into the female reproductive tract in order to find a single cell – the oocyte. The spermatozoa subsequently ignore the thousands of cells they make contact with during their journey to the site of fertilisation, until they reach the surface of the oocyte. At this point, they bind tenaciously to the acellular coat, known as the zona pellucida, that surrounds the oocyte and initiate the chain of cellular interactions that will culminate in fertilization. These exquisitely cell- and species-specific recognition events are among the most strategically important cellular interactions in biology. Understanding the cellular and molecular mechanisms that underpin them has implications for diagnosis of the aetiology of human infertility and the development of novel targets for fertility regulation. Herein, we describe two models indicating the plethora of highly orchestrated molecular interactions underlying successful sperm zona binding and sperm oocyte fusion. Received 17 December 2006; received after revision 31 January 2007; accepted 16 March 2007     

精子载体法转基因动物研究进展

精子作为基因的载体制作转基因动物,以其简单、高效和广泛适用等特点而吸引众多的研究小组在不同水平上进行研究。本就四个方面：不同种动物精子与ＤＮＡ结合的研究;精子与ＤＮＡ结合的调控机制;与精子结合的ＤＮＡ的定位及去向;利用精子载体法制作转基因动物的研究,对他们的研究加以系统综述。     

Analysis of the characteristics of gastrointestinal motility based on Hilbert-Huang transform method

Pressure activity data as an important index of gastrointestinal (GI) motility can be obtained from the wireless radiotelemetry capsule. The Hilbert-Huang transform (HHT) method, which is more effective to process non-stationary signal, is proposed to identify the characteristics of GI motility. We decompose the pressure activity data into intrinsic mode functions (IMFs),calculate the Hilbert marginal spectrum and attain the peristalsis characteristics of GI tract. The IMFs represent the peristalses modes of GI tract activity embedded in the pressure data. The time-varying characteristic of the method suggests that the HHT is suitable to accommodate other non-stationary biomedical data analysis.     

实验Beagle犬精液冷冻保存方法初探

实验比格犬是生物医学研究中较常用的实验动物。采用以精液冷冻保存为基础的人工授精技术将大大推动实验犬的繁殖育种工作,为此,本实验尝试用两种不同配方的冷冻保存液,三种不同的冷冻程序进行了比格犬精液的冷冻实验,结果比格犬精液经冷冻保存后,最高解冻存活率达７４％,解冻复苏率达到９７．３％,此方法用于犬的人工授精具有一定的可行性。     

继发性输尿管梗阻对大鼠活体输尿管蠕动规律及ICC样间质细胞的影响

目的探讨继发性输尿管梗阻后活体大鼠输尿管蠕动及肾盂输尿管交界处ICC样间质细胞形态和密度的变化规律,并分析两者的相关性。方法清洁级SD大鼠35只,随机分为7组,每组5只。大鼠被分为3个大组,5只作为正常对照组（C）,5只作为假手术组（S）,其余作为实验组（S1～S5）：梗阻3 d组S1、梗阻1周组S2、梗阻2周组S3、梗阻4周组S4、梗阻8周组S5。实验组动物建立左侧输尿管完全梗阻模型。外接压力感受器法测定各组大鼠输尿管蠕动活性,分析其变化规律。取实验侧肾盂输尿管交界处上下各0.2 cm输尿管,采用免疫组织化学显色,光镜下计数ICC样细胞密度并观察形态。结果所有实验组大鼠左肾盂及输尿管均见明显扩张积水,动物模型建立成功。各组输尿管蠕动频率分别为：C（19.6±4.037）次/min,S（18.8±2.168）次/min,S1（4.6±1.140）次/min,S2（8.0±2.345）次/min,S3（5.4±1.673）次/min,S4（5.4±1.517）次/min,S5（6.2±1.789）次/min,但输尿管蠕动频率在正常对照组（C）和假手术组（S）间没有显著性差异（P=0.706）。各实验组输尿管蠕动频率较正常对照组（C）和假手术组（S）有所下降,但呈现出先下降后上升再下降的趋势,这种差异除了在S1和S2组之间有统计学差异外,在其他各个实验组之间没有统计学差异。各组ICC样间质细胞的密度分别为：C（7.20±2.29）个/视野,S（7.02±2.68）个/视野,S1（3.54±1.85）个/视野,S2（6.30±1.19）个/视野,S3（4.30±0.67）个/视野,S4（4.42±1.45）个/视野,S5（4.70±1.09）个/视野。除了S2组以外的各实验组ICC样间质细胞的密度较正常对照组（C）和假手术组（S）有所下降,但呈现出先下降后上升再下降的趋势,这种差异在各个实验组之间没有显著的统计学差异。大鼠输尿管蠕动频率变化趋势与ICC样间质细胞的变化趋势有很好的相关性。结论大鼠肾盂输尿管交界处ICC样间质细胞的密度变化与输尿管蠕动活性关系密切,为将来研究ICC样间质细胞在泌尿系统中的作用奠定了一定的基础。     

大黄鱼精子冷冻复苏后活力和超微结构的变化

大黄鱼精子以甘油为冷冻保存剂,经冷冻-解冻复苏后观察精子的活力和超微结构变化,并进行人工授精,观察冻精的受精能力.实验结果表明,冷冻精子的活力较高(83.1±6.2)%.大部分冷冻精子结构完整,进行人工授精可以获得较高的受精率(71.5±11.6)%.与鲜精对照组比较,仍存在差异(P<0.05).部分冷冻-解冻后的精子结构出现异常,畸形率达到29.3%(P<0.01).较常见的异常是精子质膜膨胀或破损,核膜消失,染色质解体,线粒体嵴消失,轴丝断裂成许多段等.冷冻精子结构异常可能是冻精解冻复苏后精子活力和受精力下降的主要原因.     

Sperm ultrastructure in two species of Gyraulus (Gastropoda: Pulmonata: Planorbidae)

Sperm morphology offers a rich source of potentially informative characters for gastropod taxonomy and in this study it was used to provide additional information for Gyraulus (Armiger) crista (Linnaeus, 1758), whose taxonomic position within the Planorbidae Rafinesque, 1815 remains uncertain. Sperm morphology in G. (A.) crista and G. (Gyraulus) albus (Müller, 1774), the type species of the genus, was examined using light microscopy, scanning electron microscopy and transmission electron microscopy. The ultrastructure of spermatozoa in the two species was found to conform to the general pattern characteristic of the Hygrophila Férussac, 1822: the spermatozoa had an anterior head containing an acrosomal complex (apical vesicle and acrosomal pedestal) and cone-shaped nucleus, followed by a very long midpiece with glycogen spirals, and then by a glycogen piece and tail. Although the spermatozoa of the two species shared some common features (one nuclear keel and four glycogen spirals), they differed significantly in length, morphology of the annulus and structure of the spiral surface ridges. There were also some differences in the size and structure of the acrosomal pedestal and the shape of the nucleus. The spermatozoa of the two Gyraulus species are compared with those of other Hygrophila and the possible importance of sperm morphology for the taxonomic status of G. (A.) crista is discussed.     

鸡小肠肌间神经丛的胚后发育

用Ｇｒｏｓ浸银法对１ｄ，７ｄ，２１ｄ，４２ｄ，７０ｄ和成鸡的小肠肌间神经丛进行观察比较．结果表明，鸡小肠肌间神经丛的胚后发育随着鸡的个体发育而逐渐完善，纤维束逐渐密集，神经节逐渐增大，其中细胞数目也呈递增趋势．在４２ｄ鸡的肠神经丛内，大的Ｄｏｇｉｅｌ细胞已趋成熟．７０ｄ鸡的肌间神经丛已与成鸡相似．     

Injection of a soluble sperm fraction into sea-urchin eggs triggers the cortical reaction

Summary Fertilization membranes from around unfertilized sea-urchin eggs after microinjection of a soluble spermatozoa fraction isosmotic with seawater. This demonstrates that the spermatozoon contains a chemical that triggers an increase in cytosolic calcium, leading to exocytosis of cortical granules. It also demonstrates that the triggering mechanism does not require an externally-activated egg-membrane process. Further experiments show that the chemical trigger is not calcium.