鸭病毒性肠炎病毒强毒株的形态发生学与超微病理学研究

应用透射电镜和超薄切片技术,研究鸭病毒性肠炎病毒(duck enteritis virus,DEV)CH强毒株人工感染成年鸭后,病毒在宿主细胞内的形态发生及各组织器官的超微结构变化.结果表明,感染后不同时间剖杀及发病后死亡鸭的肝、肠、脾、胸腺、法氏囊等组织器官中,均观察到典型的疱疹病毒粒子.病毒主要的靶细胞为淋巴细胞、网状内皮细胞、成纤维细胞、巨噬细胞、血管内皮细胞、肠道上皮细胞、肠道平滑肌细胞和肝细胞等.DEV的核衣壳有空心型、致密核心型、双环型和内壁附有颗粒型四种形态,存在胞核和胞浆两种装配方式.病毒核衣壳可在核内获得皮层,通过核内膜获得囊膜成为成熟病毒;也可通过内外核膜进入胞浆,在其中获得皮层,然后在各种质膜上获得囊膜,最后成熟病毒释放到细胞外.伴随着病毒的复制、装配和成熟,细胞中出现多种核内和胞浆包涵体、核内致密病毒核酸颗粒、微管和中空短管以及胞浆内膜包裹的电子致密小体、双层管等病毒相关结构.超微研究表明,组织细胞有坏死和凋亡两种变化.坏死细胞肿胀甚至破裂,线粒体肿胀空泡化,粗面内质网扩张,核糖体脱落,有的细胞器甚至完全崩解,染色质或固缩或溶解.凋亡细胞则染色质聚集,胞浆凝聚深染,细胞膜上有大量空泡,并有凋亡小体形成.细胞坏死与凋亡往往同时存在,疾病发生过程中,脾、胸腺、法氏囊以及小肠固有层中的淋巴细胞凋亡数量明显增多.     

大菜粉蝶颗粒体病毒的形态发生及细胞病理的超微结构观察

本文叙述感染大菜粉蝶颗粒体病毒后,病虫脂肪体细胞超微结构的改变,大菜粉蝶感染后24小时,病虫脂肪体细胞开始出现明显的病变,整个病程是,在开始时细胞核内出现清晰区并出现病毒发生基质,核膜多点成套增生,其后核膜断裂,大量膜样结构聚集在病毒发生基质的周围,核衣壳大量产生,有一部分核衣壳从这些病毒发生基质四周的膜样结构碎片上获得套膜,荚膜蛋白沉积形成成熟的病毒荚膜,或称包含体;另一部分则排列在胞浆内的空泡边缘上;其余的核衣壳则从细胞边缘“芽突”而获得套膜,另外还描述环孔片层及线粒体改变。     

兔病毒性出血症(暂定名)的研究 Ⅰ.兔病毒性出血症引起兔肝细胞的超显微结构病变

兔病毒性出血症是一种致死性急性传染病,取体温41℃但尚未死亡的病兔的肝组织,经电镜超薄切片研究,在肝细胞核内可见大量成熟的,直径约36nm的球状无膜病毒颗粒,还可看到细胞核的严重病变,细胞质内的细胞器,包括线粒体,内质网系统也发生不同程度的病变,这一类病毒在细胞核内复制和装配,这提示该病毒可能是一种DNA病毒。     

玉米叶片细脉原生韧皮部筛分子的分化和超微结构 : 原生质体的变化

玉米（ＺｅａｍａｙｓＬ．）叶片细脉原生韧皮部筛分子开始分化时,首先出现长的粗面内质网潴泡和增厚的细胞壁,随后在质体中出现其特征性的拟晶体内含物。随着分化的进行,长的粗面内质网潴泡转化为较短的形态,最后聚集成一些小的堆叠并失去其核糖体。细胞核发生退化,但常保持到成熟期的后期,此时的细胞核由双层核膜或某些部位仅由内核膜包被,内含电子致密的不定形染色质团块。随后双层核膜破裂而变得不连续。在细胞核开始退化时,核周腔局部膨大。有的膨大核周腔的外核膜破裂,并伴随邻近的部分细胞质解体。在核退化过程中,除内质网外,质体和线粒体的结构也发生变化,而核糖体、细胞质基质、液泡和高尔基体则解体消失。成熟原生韧皮部筛分子的原生质组分分布在细胞边缘,由质膜、线粒体、小的滑面内质网堆叠及具拟晶体的Ｐ型质体组成。随着邻近后生韧皮部筛分子分化的进行,成熟原生韧皮部筛分子的原生质组分逐渐退化,最后消失。     

养殖对虾一种新杆状病毒的研究

应用超薄切片、负染色和蔗糖梯度超离心技术,在自然发病和人工感染的对虾肝、肠、淋巴样器官、鳃和肌肉组织中,发现并纯化了一种新杆状病毒.该病毒直径96～112nm,是已知对虾病毒中最粗的一种.中央是高电子密度的核心,外裹衣壳和囊膜,两膜之间有宽阔的间隙,这是已报道的任何一种对虾杆状病毒所没有的.纯化的病毒核衣壳表面有螺旋排列的亚单位,这也是本病毒特有的.主要靶细胞是淋巴样细胞,未在肝、肠和鳃上皮细胞中观察到,这与对虾杆状病毒无一例外地侵染某一种上皮细胞迥然不同.病毒仅在靶细胞核内增殖,不形成封入体或包涵体,它是一种迄今未曾报道的新病毒,称之为“淋巴样细胞核型杆状病毒”.     

中国对虾非包涵体杆状病毒在体内的感染与发生

在感染发病成虾的肝胰腺和中肠上皮细胞的胞核内,出现大量病毒发生基质,核衣壳,套膜和完全的病毒粒子。病毒粒子为短杆状,两端呈钝园形,平均大小约为２５０－３００×ｌ１０ｎｍ,在核内无包涵体形成。在胞质内发现伴随病毒拉子并具有双层膜的蛋白质结构,这种结构建议称为该病毒的“封入体”。同时,我们认为这种无包涵体的杆状病毒,有可能应归属于杆状病毒科的第三个亚组。     

桑萎缩病的类菌原体病原物及其超微病变特征

对感染桑萎缩病的桑叶及嫩梢进行超薄切片的电镜观察发现,其韧皮部组织,筛管及伴胞内有多型性类菌原体。菌体为圆形及椭圆形,大小约为50～160nm,双层膜,厚度约为8～10nm,内含物中具有核质样的纤维状物质,而在健株叶梢中未观察到任何病原体．随着病害的发展,可观察到细胞成份的降解。第一,在感病植株叶肉细胞内存在部分细胞核的降解、核膜破裂或核质流失甚至核仁分散消失。第二,叶绿体内有不同程度的淀粉粒和嗜锇颗粒累积,部分叶绿体外膜破裂,基质流失,基粒降解。第三,线粒体及粗面内质网在数量上有所增加,部分线粒体嵴已降解。     

日本沼虾精子发生的研究

对日本沼虾精子发生全过程的电镜观察表明：精原细胞核染色质分散,胞质内有线粒休、内质网的分布。初级精母细胞核染色质块状,不均匀地分布于核中,内质同多小泡多。次级精母细胞核染色质大多分布于核膜内侧,内质网聚集成团,精细胞分化形成精子的早期,胞核增大,核侧形成内质同多小泡的聚合体;中期的核内染色质浓缩,同时形成空囊状结构,     

拟南芥根原生韧皮部筛管分子的超微结构

运用高压冷冻替代方法固定处理材料,在透射电镜下观察了拟南芥(Arabidopsis thaliana L.)根原生韧皮部筛管分子在发育过程中的超微结构变化.结果表明:在筛管分子发育过程中,细胞核具有细胞程序化死亡的典型特征,出现核膜内陷、核质聚集并边缘化、核膜破毁以及最后核消失.核膜在破毁前一直呈饱满状态,未出现核膜皱缩、核裂瓣和核周腔明显膨大等现象.在成熟筛管分子的细胞质内,具单层膜的淀粉状颗粒.这些淀粉状颗粒常与线粒体在一起,可能为线粒体的产能活动提供基质.小液泡发生于内质网,未见大液泡的形成.     

感染大麦黄花叶病毒(BaYMV)的大麦细胞质内含体及细胞器病变的研究

超薄切片电镜观察表明,在感染大麦黄花叶病毒(BaYMV)的大麦(品种“早熟3号”)叶肉细胞中,液泡周围偶而可看到病毒颗粒束,在发病后期黄化或坏死的叶肉细胞中,可见到散布的病毒颗粒。在所有表现症状的病叶叶肉细胞,表皮细胞和木质部薄壁细胞中均可观察到风轮体、束状体、板状集结体以及膜状体等细胞质内含体,未见 卷简体和细胞核内含体。感病初期细胞中,细胞质丰富,核糖体数量增加,内质网肥大,随着病毒症状发喂,叶绿体、线粒体等细胞器逐渐肿大,外膜破裂直至解体。     

Raymond Gosling: the man who crystallized genes

On April 25th 1953, three publications in Nature forever changed the face of the life sciences in reporting the structure of DNA. Sixty years later, Raymond Gosling shares his memories of the race to the double helix.It has not escaped our attention that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.James D Watson and Francis HC Crick [1]By including this statement in their April 25th 1953 Nature article describing a model for the structure of DNA, Watson and Crick made one of the great understatements in history. In that moment, the seeds for the double helix''s infamy - alongside the names ''Watson'' and Crick'' - were sown. Lesser known outside scientific circles is that this article did not include one iota of experimental data: Watson and Crick, who were based at the University of Cambridge''s Cavendish laboratory, contributed deductive reasoning alone to the double helix model, albeit reasoning of an undoubtedly Nobel Prize-worthy standard. Instead, as has now been described many times, the model relied on X-ray diffraction data obtained by others, at King''s College, and these data did not reach Watson and Crick by entirely wholesome means [2]. To add to the insult, Watson and Crick''s report of the double helix did not fully credit the work of King''s as being essential to the construction of their model, although the King''s team did enjoy co-publication of their data alongside the double helix article, in the form of two articles in the same issue of Nature [3,4]. One of these articles described the X-ray diffraction work performed by senior researcher Rosalind E Franklin, together with PhD student Raymond G Gosling, and contained the highest quality diffraction patterns yet achieved for DNA [3]. It was these data that had proved invaluable in Watson and Crick''s quest for the double helix.Earlier still, before Franklin arrived at King''s, Gosling had achieved a major breakthrough in the search for DNA''s structure when he became the first person to crystallize genes, under the guidance of Maurice Wilkins, who was the lead author of the other King''s article to accompany Watson and Crick''s model [4].Watson published his controversial memoir of the discovery, aptly named ''The Double Helix'', in the 1960s [5], and in doing so propelled the story to worldwide fame, establishing DNA''s structure as an icon of science in the popular imagination. However, events were relayed in Watson''s book very much from his own point of view and at times, it has been argued, even verged on the fictitious.Aside from Watson, Ray Gosling is the only surviving member of the select group of seven scientists to feature as an author on one of the three Nature articles. Gosling and his wife, Mary, were kind enough to welcome Genome Biology into their home, where he shared with us his perspective of the events of 60 years ago.Elsewhere, Genome Biology has marked the anniversary by canvassing our Editorial Board for their opinions on the most important advances in the field since 1953 [6].     

我国小鹅瘟研究进展及成就

小鹅瘟是导致雏鹅死亡的常见疾病之一,可造成巨大经济损失,严重危害养鹅业的发展。为了科学认识和积极防控小鹅瘟,我国同行进行了长期不懈的研究,取得了一系列原创性成果。在全世界率先发现并鉴定了小鹅瘟病毒,并对其变异特点进行了遗传进化分析,基本调研清楚了小鹅瘟在我国的发生区域和流行规律。在传统检测技术的基础上,引入免疫学技术和分子生物学技术,建立了一系列快速检测新方法;研制成功高免血清、种鹅用弱毒疫苗、雏鹅用弱毒疫苗和细胞适应弱毒株培育的新型疫苗,使我国小鹅瘟得到了有效的控制。这些成果和进展为我国小鹅瘟的研究与防治奠定了基础。     

鹅源鸭瘟病毒和小鹅瘟病毒在同一宿主系统增殖的观察

本文首次报道了鹅源鸭瘟病毒(DPV—Ⅰ)和鸭胚化小鹅瘟病毒(GPV—Ⅰ)能同时在同一鸭胚内复制增殖,未发现干扰作用,在理论上说明某些不相关的两种病毒可在同一宿主增殖,实践上为利用同一鸭胚研制二联疫苗提供了依据。研究结果表明:1.DPV—Ⅰ和GPV—Ⅰ联合感染同一鸭胚后,其尿囊液在电镜下见两种病毒,DPV—Ⅰ呈园形或椭园形,有囊膜,直径为38—109nm,GPV-Ⅰ呈园形,无囊膜,直径为18—25nm;2.含毒尿囊液使鸭胚成纤维细胞(DEF)单层发生细胞病变作用(CPE),证实存在DPV-Ⅰ,而用小鹅瘟微量免疫扩散(MID)试验,又能检出GPV-Ⅰ抗原;3.含毒尿囊液免疫鹅的血清中存在抗两种病毒的(?)和抗体和GPV沉淀抗体;4.含毒尿囊液免疫的成鹅对DPV强毒攻击有相当免疫力,免疫鹅血清能中和GPV,使其失去对鸭胚的致病力;5.GPV-Ⅰ单独或与DPV-Ⅰ联合感染DEF单层后,均未见在细胞上复制。     

雏鹅新型病毒性肠炎病毒的诊断与防控研究

对近年来全国各省市出现的雏鹅新型病毒性肠炎病毒(New type gosling viral enteritis virus, NGVEV)流行病学、临床症状、病理组织结构、病原学、病毒的检测和诊断、免疫预防、临床预防和治疗等方面的研究情况进行了论述.该病是由腺病毒引起的一种尚未被认识的新病毒,目前仅有NGVEV高免血清的预防和治疗效果较好,其余药物和生物制剂都尚需要进一步研究和改良.这些研究结果可为进一步深入研究和开发有效的药物提供基础资料,进而可提高我国养鹅业的经济效益.     

Characteristics of the membranes of the pellicle of the ciliatePseudomicrothorax dubius

Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.     

The early development of the tail and the transformation of the shape of the nucleus of the spermatid of the domestic fowl,Gallus gallus

Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices