三种波段电磁辐射致大鼠睾丸损伤的比较

目的对比性探讨电磁脉冲(EMP)、S带高功率微波(S-HPM)和X带高功率微波(X-HPM)三种波段电磁辐射致睾丸组织受损的近期和远期效应及其相关敏感指标。方法雄性Wistar大鼠192只,随机分为EMP组、S-HPM组、X-HPM组和对照组,于照后不同时间点采集睾丸组织称重,光镜观察睾丸损伤,并用图像分析技术对曲细精管病变进行定量分析。结果三种波段电磁波辐照后睾丸结构和生精细胞形态损伤基本相似:早期睾丸重及睾丸重/体重比值呈下降趋势;曲细精管生精上皮变薄,生精细胞排列紊乱,精原细胞变性坏死并由管壁脱落,精母细胞和精子数量减少并团聚于管腔中央,支持细胞和间质细胞不同程度变性;曲细精管受损百分率显示EMP组最重,S-HPM最轻,生精细胞受损数量与程度显著增加(P0.05)。结论三种波段电磁辐射对睾丸生精细胞的损伤,具有速发性、时相性、分布不均一性特点;损伤程度呈EMPX-HPMS-HPM;睾丸曲细精管受损百分率可定量反映其损伤程度,可望成为评估电磁辐射致睾丸损伤的敏感指标之一。     

蝮蛇短尾亚种雄性生殖周期的初步研究

蝮蛇短尾亚种雄性生殖周期属夏季型。精子发生于早春,到秋天完成。6月份曲细精管直径明显增大,管腔内偶见成熟的精子,9月份成熟的精子排入副睾及输精管中过冬。蝮蛇有春、秋两季交配活动,秋季交配后排入雌体的精子贮藏在输卵管及泄殖腔的皱壁内,供翌年卵成熟受精之用。     

雄性棕三趾鹑睾丸的年周期变化

2007年9月至2008年8月,于每月中旬从海南澄迈县取棕三趾鹑(Turnix suscitator)雄性成体8～11只进行解剖,观测性腺形态及其组织学特征.结果表明,棕三趾鹑睾丸重量和体积、曲细精管直径和生精上皮厚度呈周期性变化.3月睾丸明显增重增大,7月达到最大,10月明显变小减轻,12月最小.生精活动开始于3月,4～9月为旺盛的活跃期,从基膜到管腔,各级生精细胞依次排列,10月开始减弱,11月接近停止.根据睾丸各项指标的变化规律,显示棕三趾鹑11月至翌年2月为非繁殖期,3～10月为繁殖期.     

合欢皮总皂苷对雄性小鼠的抗生育作用研究

目的探讨合欢皮总皂苷对雄性小鼠的抗生育作用。方法将60只健康的雄性性成熟昆明小鼠随机分成3个试验组和1个对照组,各试验组小鼠灌胃540 mg·(kg·d)-1,270 mg·(kg·d)-1和135 mg·(kg·d)-1的合欢皮总皂苷水溶液,对照组自由饮水,灌胃1周后按雌雄比2∶1合笼,继续对雄鼠灌胃至19 d,采集雄性小鼠的血液并测定血液生化指标,剖检灌胃雌性小鼠,统计雌性小鼠的怀孕率,测定雄性小鼠睾丸与附睾的脏器系数及附睾精子活力,并固定睾丸和附睾,研究其组织学变化。结果与对照组相比较,雄性小鼠灌胃合欢皮总皂苷后,导致雌性小鼠的怀孕率降低,睾丸脏器系数和附睾精子活率极显著降低(P<0.01),精子畸形率极显著升高(P<0.01)。光学显微镜下,试验组小鼠睾丸和附睾均有一定程度的损失,睾丸生精细胞排列疏松,间质减少,可见曲细精管内有多核巨噬细胞浸润,各级生精细胞脱落。附睾具正常的管腔结构,但能明显观察到管腔内精子几乎消失。结论合欢皮总皂苷对雄性小鼠具有抗生育作用,主要通过影响精子的生成及破坏生精组织而达到。     

棕色田鼠睾丸及附睾胚后发育的形态学变化

通过组织学方法,对产后1 d、10 d、25 d、45 d、60 d及70 d的棕色田鼠Lasiopodomys mandarinus睾丸和附睾发育进行了观察,以探讨其精子发生特点.结果 发现,1 d棕色田鼠的生殖细胞主要是生殖母细胞和前精原细胞;10 d出现大量精原细胞,睾丸间质细胞明显;25 d出现精子细胞;45 d有少量精子出现;60 d和70 d具有各级生精细胞,睾丸生精小管和附睾内出现大量成熟精子.睾丸生精小管管径和生精上皮厚度随日龄增加,于60 d达到最大;附睾管腔直径和附睾上皮厚度也于60 d达到最大.这些结果表明,棕色田鼠在生后45 d左右进入青春期,60 d左右达到性成熟,精子的产生及成熟与附睾的发育同步.     

睾丸生理

(一)睾丸的结构睾丸位于阴囊内,其表面包有一层坚韧的纤维膜即白膜。由白膜向内伸出许多不完整的纤维隔,即睾丸小隔,这些睾丸小隔把睾丸分成许多间隔,称睾丸小叶,每个小叶内含有2—4条曲细精管,小叶内的曲细精管向纵隔集中,并互相结合成直细精管,随后在睾丸纵隔内吻合而形成小管网,即睾丸网。睾丸网再发出8—15条输出小管进入附睾。精子就是在曲细精管中源源不断发生。 (二)精子发生整个精子发生过程都在睾丸的曲细精管内进行。曲细精管内有两类细胞,即生精细胞和支持细胞。曲细精管间的疏松结缔组织构成睾丸     

细胞松弛素E对大鼠生精细胞发育的影响

本文采用微丝抑制剂——细胞松弛素E对大鼠生精细胞发育的影响作了形态学观察,特别对支持细胞骨架复合体的作用进行了较为详细的研究。结果表明睾丸内注射0.1ml,1000μmol/L～2000μmol/L,细胞松弛素E,6-14小时后,光镜下可见曲细精管上皮排列疏松,组合紊乱,有的生精上皮基底部出现双核和三核的圆形细胞和多核巨精子细胞,管腔内出现未成熟的精子;在第ⅤⅢ～Ⅸ期曲细精管上皮中,有许多第8、第9期的精子细胞顶体不指向基底方向,属定向不正的精子。电镜下,实验组动物可见一些面向第8-18期精子细胞顶体的支持细胞骨架复合体出现不同程度的缺如,有的断裂成小段;有的破坏仅发生在顶体上方;有的几乎全部丢失,并有类管球复合体的形成。另外,在高渗液处理下,可见精子细胞顶体和支持细胞间的间隙扩大。最后对微丝在精子发育中的作用进行了讨论。     

狗施行附睾尾化学注射绝育后寒九附睾内的免疫复合物观察

５只性成熟成年雄性比格犬被施行附睾尾逆向注射１０％精氨酸锌０．５毫升。一般饲料饲养两月后处死作病理检查,发现精子在睾丸曲细精管内的生成及在附睾管内的成熟均受到影响,附睾尾管腔内精子降到了极少程度且多已变性。免疫组织化学反应发现睾丸间质及附睾管上皮间隙内,附睾间质中均有大量免疫复合物的沉积,而其它主要生命器官均未发现异常。结果表明,精氨酸锌附睾尾注射的绝育作用是肯定的,其伴随出现的抗精子抗体及免疫复合物仅对睾丸、附睾及生育功能产生影响,对机体主要生命器官并无损害。     

薄荷油对雄性小鼠的抗生育作用研究

目的探讨薄荷油对雄性小鼠的抗生育作用。方法将60只健康的雄性性成熟昆明小鼠随机分成3个试验组和1个对照组,各试验组小鼠灌胃0.135 g/(kg·d),0.27 g/(kg·d)和0.54 g/(kg·d)的薄荷油0.5%羧甲基纤维素钠(sodium carboxymethylcellulose,CMC)混悬液,对照组灌胃0.5%羧甲基纤维素钠溶液,灌胃1周后按雌雄比2∶1合笼,继续对雄鼠灌胃至19 d,采集雄性小鼠的血液并测定血液生化指标,剖检灌胃雌雄小鼠,统计雌性小鼠的怀孕率,测定雄性小鼠睾丸与附睾的脏器系数及附睾精子活力,并固定睾丸和附睾,研究其组织学变化。结果与对照组相比较,雄性小鼠灌胃薄荷油后,导致雌性小鼠的怀孕率降低,睾丸脏器系数和附睾精子活率极显著降低(P<0.01),精子畸形率极显著升高(P<0.01)。光学显微镜下,试验组小鼠睾丸和附睾均有一定程度的损伤,睾丸间质减少,睾丸各级生精细胞排列疏松,曲细精管内有多核巨噬细胞浸润。附睾具正常的管腔结构,但能明显观察到管腔内精子减少。结论薄荷油对雄性小鼠具有抗生育作用,且主要通过影响精子的生成及破坏生精组织而达到,具有实际应用价值,可进一步开发成环境友好型鼠类抗生育药剂。     

国人睾丸、附睾和输精管的氧化还原酶的组织化学观察

本文收集了１９—３８岁国人正常男性新鲜睾丸、附睾和输精管１３例,进行了氧化还原酶组织化学染色、光镜定位及定性观察。结果表明：睾丸曲细精管和输出小管上皮的ＧＤＨ,ＮＡＤＨＤ,ＮＡＤＰＨＤ,ＳＤＨ,ＧＰＤＨ,ＩＣＤＨ,ＭＤＨ,ＬＤＨ和Ｇ－６－ＰＤＨ９种酶;睾丸间质细胞和附睾管上皮的ＮＡＤＨＤ,ＮＡＤＰＨＤ,ＳＤＨ,ＩＣＤＨ,ＭＤＨ,ＧＤＨ,ＬＤＨ和Ｇ－６－ＰＤＨ８种酶;输精管的ＮＡＤＨＤ,ＮＡＤＰＨＤ,ＩＣＤＨ和ＧＤＨ４种酶的酶活性呈强阳性或极强阳性。提示输出小管和头部附睾管含有的多种氧化还原酶对精子功能成熟有极重要作用。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.