Malignant fibrous histiocytoma: an ultrastructural perspective

Malignant fibrous histiocytoma is a frequent diagnosis, but the relationship of the tumors to histologically similar soft tissue neoplasms is controversial. In this study, 157 examples representing the 4 main subtypes were reviewed by light microscopy and each tumor was studied with the electron microscope. Immunohistochemical stains were performed on 77 tumors. Electron micrographs on 100 fibrosarcomas were reviewed for comparison. Malignant fibrous histiocytomas often closely resemble fibrosarcomas at the ultrastructural level and differences between the two are generally of degree only. Evidence for true histiocytic differentiation was not found. The immunohistochemical results did not contradict the authors' impression from electron microscopy that malignant fibrous histiocytoma forms part of the histologic spectrum of tumors of fibroblasts.     

HLA-A*0201与EGFP融合蛋白表达载体的构建及其在K562细胞的表达和定位

目的:构建增强型绿色荧光蛋白(EGFP)与HLA-A^*0201(A^*0201)融合蛋白哺乳动物细胞表达载体,分析其在K562细胞中的表达和亚细胞定位。方法:以RT-PCR方法克隆A^*0201cDNA,构建A^*0201-EGFP融合蛋白表达载体,转染K562细胞,以流式细胞仪和激光共聚焦显微镜分析融合蛋白的表达及其亚细胞定位。结果:从两个HLA-A2阳性供者外周血细胞中克隆到A^*0201cDNA编码区全长序列。通过PCR方法在起始位点前加入Kozak序列并删除终止密码,成功构建A^*0201-EGFP融合蛋白表达载体。以该质粒转染K562细胞,5h后A^*0201和EGFP的表达百分率分别为25.12±2.26、27.37±3.59,24h后表达水平无明显提高。表达的融合蛋白主要分布于细胞膜上,胞内分布较少。相反,转染空载体的细胞不表达A^*0201分子,仅表达EGFP,且其在细胞内呈弥散样分布。结论:成功构建A^*0201-EGFP融合蛋白表达载体,并在K562细胞中得到表达,表达产物主要分布于细胞膜表面,提示表达该融合蛋白的K562细胞是潜在的人工抗原提呈细胞。     

Ⅲ型胶原肾小球病的形态学观察

目的了解Ⅲ型胶原肾小球病的形态学改变,并对Ⅲ型胶原可能的细胞来源进行初步探讨。方法对3例肾活检组织进行光镜、免疫荧光、电镜和Ⅰ、Ⅲ、Ⅳ型胶原及d平滑肌肌动蛋白(α-SMA)的免疫组织化学染色(SP法)观察。结果2例患者临床表现为肾病综合征,其中1例伴高血压,第3例表现为肾功能不全和肾性高血压。3例均无肾病家族史。光镜检查可见肾小球基膜内和系膜区弥漫性过碘酸-希夫反应阳性物质沉积,系膜细胞无明显增生。电镜检查在基膜内疏松层和系膜区可见大量胶原纤维沉积,系膜细胞胞膜下平行排列的束状微丝明显增加。免疫组织化学显示这些胶原纤维为Ⅲ型胶原,Ⅰ型和Ⅳ型胶原阴性,同时系膜区多数系膜细胞α-SMA阳性。结论Ⅲ型胶原肾小球病光镜、电镜及免疫组织化学上都有其特殊的病理改变。肾小球内激活的系膜细胞可能是Ⅲ型胶原的来源。     

Pituitary chromophobe adenomas consisting of prolactin cells

Summary Morphologic studies of pituitary neoplasms removed by surgery from 36 human patients revealed 8 chromophobe adenomas which differed clearly from the remaining tumors. The cytoplasm of the adenoma cells failed to stain with PAS, aniline blue, aldehyde fuchsin, aldehyde thionin, orange G or light green, but positively stained granules were found by using erythrosine or carmoisine. Immunoperoxidase technique disclosed the presence of prolactin in the cytoplasm of some adenoma cells. The adenoma cells exhibited distinct ultrastructural features such as well developed rough surfaced endoplasmic reticulum with Nebenkern formation, prominence of Golgi apparatus, presence of misplaced exocytosis as well as pleomorphism of secretory granules with a considerable variation of size ranging from 130 to 500 nm in diameter. Thus, by electron microscopy the adenoma cells showed a close resemblance to prolactin cells of the non-tumorous pituitary glands except for the reduced size and number of secretory granules.These chromophobe adenomas are regarded as representing a distinct pathological entity clearly distinguishable from other forms of pituitary neoplasms. In view of the morphologic findings and the elevation of blood prolactin level (measured in 3 patients) the term, sparsely granulated prolactin producing pituitary adenoma, appears to be the most appropriate one to designate these tumors.The authors wish to thank Dr. H. Friesen for providing the anti-human prolactin and Dr. L. A. Sternberger for the peroxidase-anti-peroxidase complex. The excellent technical assistance of Mrs. Gezina Ilse and Miss Nancy Macphail and the valuable secretarial help of Mrs. Maureen Rowling are appreciated.The work was supported in part by MA-552 grant of the Medical Research Council of Canada and by the St. Michael's Hospital Research Society.     

Morphological features of nerve terminal degeneration as part of the remodeling process in the motor endplate in adult muscles

With the exception of signs of retraction and withdrawal, there have been few morphological data concerning degenerated neural profiles in adult motor endplates. Here, investigation into the ultrastructure of the soleus motor endplates of adult rats (4 months old) turned up particular axonal degeneration in approximately 3% of the subjects. These axons occur as synaptic debris in the synaptic matrix of the motor endplate, adjacent to thin processes of the perisynaptic cells occupying the outer most layer of the motor endplate and were devoid of basal lamina. They often possessed dense-cored vesicles (50-80 nm). Axonal debris released from Schwann cell processes occurred during the period of acute sciatic neurectomy, when nerve terminals progressively disrupted within the motor endplate associated Schwann cells. Finally, immunohistochemical staining for antibodies to label macrophages (ED1 or ED2) has shown that nerve fiber-associated macrophages are located near the motor endplate. The results suggest that during the course of endplate remodeling, a few parts of the terminal branches are disposed of through spontaneous collapse, subsequent release from the Schwann cell investment, and eventual ingestion by macrophages in the perisynaptic space.     

氟化物转化细胞的超微结构观察

研究氟化物的致突变性和潜在致癌性,探讨其诱变机理。方法应用NaF诱导转化金黄地鼠胚胎细胞(SHE),以扫描和透射电镜观察其超微结构。结果该细胞群中少数细胞凋亡,大部分细胞则已逃脱凋亡转化成恶性细胞。结论氟化物对哺乳动物细胞可能具有诱变致癌性。     

单纯疱疹病毒Ⅰ型在兔脑神经细胞中的形态与形态发生

研究单纯疱疹病毒Ⅰ(HSV-Ⅰ)在兔脑神经细胞(RNC)中的形态与形态发生。方法 用电子显微镜观察超薄切片,并拍照记录。结果RNC感染HSV-Ⅰ6h后,细胞核中即可见散在核衣壳,12h后细胞核和细胞质内均可见到,但以核内多见,24h后病毒量达高峰。胶质细胞内的核衣壳多于神经元,胶质细胞和神经元的细胞质内和胞外可见少量有包膜的完整病毒。病毒颗粒为圆形或椭圆形,核心直径38～54nm,核衣壳77～100hm,成熟病毒115～129nm。结论RNC对HSV-Ⅰ高度敏感,HSV-Ⅰ在兔脑神经元和胶质细胞中的形态发生有一定的差异。     

淋巴因子激活的NK细胞杀伤肿瘤细胞的免疫电镜观察

用胶体金标记的扫描与透射免疫电镜术观察ＣＤ１６＾＋淋巴因子激活的杀伤细胞杀伤肺腺癌细胞系ＬＴＥＰａ２或人红白血病细胞Ｋ５６２的过程。发现ＣＤ１６＾＋ＬＡＫ细胞能伸出分支的指状突起较深地插入肿瘤细胞浆内，造成靶细胞表面大小深浅不等的隐窝，及陷窝内局部细胞膜损伤，在ＣＤ１６＾＋ＬＡＫ细胞这种指状突起基底部附近的浆内，有大量胞浆颗粒与囊泡聚集。靶细胞被攻击后常发生凋落型死亡。同时可见坏死型死亡。说明ＣＤ     

关于大肠癌内分泌细胞及其分泌激素意义的研究

目的了解内分泌型癌细胞（ＥＣ）及其分泌的部分激素在大肠癌中的表达,探讨其与大肠癌临床病理及预后的关系。方法应用免疫组化法对１１７例大肠癌中嗜铬蛋白Ａ（ＣＧＡ）及５种激素进行检测,其中１３例行电镜观察。结果４６例（３９．３％）含有ＣＧＡ阳性细胞（即ＥＣ）,其中３９例中２７例（６９．２％）检测到１种以上激素,ＥＣ阳性组淋巴结转移的发生率（６３．０％）高于阴性组（３９．４％）（Ｐ＜０．０５）,中低分化癌组ＥＣ（＋＋）的表达率（２５．５％）明显高于高分化癌组（６．９％）（Ｐ＜０．０５）,含ＥＣ的大肠癌生存期短,是评估预后的一个独立因子。激素５－ＨＴ、β－ＨＣＧ、ＧＬＵ、ＧＡＳＴ阳性的癌组织,分化及预后较差（Ｐ＞０．０５）。电镜观察与免疫组化检测大肠癌ＥＣ符合率达９２．３％。结论部分大肠癌中含分泌某些激素的ＥＣ,ＥＣ阳性的大肠癌组织分化差,易发生淋巴结转移,预后不良,可能与ＥＣ中某些激素产物促进肿瘤生长转移有关。     

大鼠原位肝移植及术后肝细胞超微结构观察

用５１只Ｗｉｓｔａｒ大鼠建立了新的大鼠原位肝移植手术模型,手术成功率为９２．１％,周存活率为８６．２７％。手术要点是术前供肝冷灌注;受体肝只建立门静脉血供,静脉吻合分别采用“双袖套”式吻合和“８”字外翻缝合;胆管重建采用单管支架总胆管对端吻合法。移植术后肝细胞超微结构动态观察表明：术后２周是控制免疫排斥反应的关键时期,术后８周实验鼠产生免疫耐受性,移植肝脏成活。