Human normal and neoplastic adrenocortical cells in tissue culture observed by scanning electron microscopy

Human normal and neoplastic adrenocortical cells were incubated under stimulation with ACTH and observed by scanning electron microscopy. Cultured normal adrenocortical cells gathered into small clusters, each cell of which had a polarity or orientation evidenced by two different aspects. In one aspect, the cell surface rounded up and microvilli protruded vertically. Pits were found among or close to the groups of microvilli. In the other aspect, the cell surface was flattened and well-developed microvilli ran horizontally. These two aspects of the cultured cells were thought to correspond to the cell surface facing the intercellular space and that facing the perisinusoidal space, respectively. In incubated cell clusters of adrenocortical adenomas with Conn's syndrome, most cells lost this polarity or orientation and unstimulated cells existed as unit of the clusters, but all adenoma cells reacted to ACTH in the same manner. Microvilli were distributed unevenly. Filopodia were noticed in some cells. Bleb-like structures appeared frequently and some of them were about to be extricated from the cell surface as in normal adrenocortical cells. Adrenocortical adenomas with Cushing's syndrome showed remarkable responses to ACTH. Their cell surface was unclean with the adherence of fragmented cytoplasm and bleb-like structures. Horizontally running elongated microvilli were almost indistinguishable from collagen fibrils. Moreover, collagen fibrils were entangled with microvilli.     

A teflon culture and embedding device for the study of cells by light and electron microscopy

A method is described which permits continuous light microscopic observation of cell cultures under sterile conditions. Moreover, cells or groups of cells selected in such cultures may be processed for electron microscopy, without disturbance of possible cellular interactions, in such a way that these selected cells may be observed in the electron microscope. The method is based on the use of a transparant Teflon film in culture chambers.     

Studies on human lacteal rotavirus antibodies by immune electron microscopy

In vitro studies carried out by immune electron microscopy (IEM) indicate that rotavirus aggregation detected in the stools of newborn breast-fed infants with rotavirus infection is antibody-induced. Aggregation of rotavirus particles occurred with the IgA-containing fraction of expressed breast milk (EBM) obtained five days postpartum and with the IgA- and IgG-containing fractions of a pool of EBMs containing samples collected 2-3 days postpartum. Bovine milk fractions also demonstrated this activity in the IgG- and IgA-containing fraction. Studies on unfractionated EBMs from a mother who experienced a rotavirus infection during the 43rd week of lactation showed that following rotavirus infection all three major classes of rotavirus-specific antibodies were present in breast milk, this being confirmed by enzyme immunoassay.     

Comparison of the results of asbestos fibre dust counts in lung tissue obtained by analytical electron microscopy and light microscopy.

The efficiency of the light microscope with that of the electron microscope in detecting asbestos fibres in human lung tissue was computed. Necropsy material from 55 patients who had died from asbestos related diseases was analysed independently by phase contrast microscopy and electron microscopy. As expected the number of fibres identified using electron microscopy was higher than that identified by light microscopy. By adjusting the electron allow for the limited resolving power of the light microscope, however, a significant correlation of the number of fibres identified using the two methods was obtained. The best correlation was found with specimens containing crocidolite (correlation coefficient 0.79) and amosite (correlation coefficient 0.74), while chrysotile gave a much lower correlation (correlation coefficient 0.15). The cumulated fibre diameter distribution obtained using the electron microscope suggests that the light microscope is able to visualise only 5% of crocidolite, 26.5% of amosite, and 0.14% of chrysotile present in lung tissue. Therefore, although it is possible, using the electron microscope, to predict the asbestos fibre count that would be obtained by light microscopy, the reserve prediction cannot be made: it is impossible to determine the proportion of the various asbestos mineral types using the light microscope.     

A plating method for preparation of cells for culture and for observation by light or electron microscopy

A plating technique that makes use of small volumes of cell suspensions (1–10 μl) is described. Its purpose is to permit microscopic examination or propagation in culture of the entire contents of the microdroplet. Cells are allowed to settle by gravity on Millipore filters where they rapidly and firmly attach after 20 minutes of incubation at 37°C. Such cells can be used for long- or short-term cultures and can be processed for light microscopy and transmission or scanning electron microscopy. The method is particularly useful for preparing cell suspensions for scanning electron microscopy since it is possible to match light photomicrographs with scanning electron micrographs of identical cells.     

胃肠道间质瘤的光镜、免疫组织化学和超微结构的观察

目的 研究胃肠道间质瘤（GISTs）的光镜,电镜形态特点和免疫组织化学在诊断中的价值,探讨肿瘤的组织来源和分型。方法 对GISTs进行光镜和超微结构的观察,用EnVision二步法免疫组织化学方法检测波形蛋白,CD117（c-kit),CD34等8种抗原标记物在肿瘤中的表达情况。结果 65例GISTs占同期消化系统间叶性肿瘤的85．5％（65／76）;其中梭形细胞为主的有46例,伴有上皮样细胞的有13例,单纯由上皮样细胞组成的有6例,瘤细胞呈长,短梭形和圆形,胞质弱嗜酸,常见核端空泡,有时呈印戒样或透明细胞样;排列呈旋涡状,栅栏状或弥漫性巢状。超微结构表现出树枝样突起,神经内分泌颗粒,桥粒样连接等神经分化特点,或（和）胞质内出现密斑,密体等肌性分化。免疫组织化学显示肿瘤组织中抗原标记物表达阳性率波表蛋白为100％（65／65）,CD11793．8％（61／65）,CD3478．5％（51／65）。结论 GISTs是消化道最常见的间叶性肿瘤,光镜形态与真性肌源性和神经源性肿瘤极为相似,电镜和CD117,CD34等免疫标记物配合使用可对其做作出正确诊断,GISTs可能起源于多潜能的,卡哈尔间质细胞样的前体细胞。     

Rapid serotyping of human rotavirus strains by solid-phase immune electron microscopy.

Nine cell culture-adapted, as well as 30 clinical, human rotavirus (HRV) strains from fecal extracts of children with primary HRV infection were typed by rapid solid-phase immune electron microscopy with protein A and absorbed DS-1 (HRV serotype 2), Wa (serotype 1), and VA70 (assumed serotype 3) rabbit immune sera. As a reference typing test for cell culture-adapted strains, the neutralization assay was used, whereas for noncultivatable strains typing was done for comparison, indirectly, based upon the differential neutralization reactivity of convalescent-phase serum samples from patients with primary HRV infection versus the three reference HRV serotypes. Typing results by solid-phase immune electron microscopy for all strains examined were in complete agreement with those obtained by the neutralization assay, both on cell culture-adapted strains with the three reference rabbit antisera and on three reference HRV strains with human convalescent-phase serum samples. Since adaptation to growth in cell cultures of clinical HRV strains from stool specimens is a time-consuming procedure and is often unsuccessful, solid-phase immune electron microscopy is preferred over the neutralization assay, giving results in about 16 h and also allowing typing of HRV strains from stool specimens low in virus particles. In addition, HRV strains reacting differently from the three reference serotypes may be easily selected by solid-phase immune electron microscopy for further characterization, as was the case for one strain in this study.     

Pseudoreplica electron microscopy for the detection of rotavirus: comparison with high-speed centrifugation electron microscopy and ELISA

Three-hundred and sixty-three stool specimens from patients with diarrhoea were examined for rotaviruses to compare the sensitivity of the pseudoreplica technique (PSD-EM) to that of high-speed centrifugation EM (HSC-EM) in relation to a commercially available (Rotazyme, Abbott) enzyme-linked immunosorbent assay (ELISA). In ELISA-positive cases, both methods were of equal sensitivity. However, in borderline (+/-) and ELISA-negative specimens, PSD-EM detected 31 of 48 (64.6%) and 18 of 229 (8%) positive specimens respectively, compared to only 22 of 48 (45.8%) and one of 229 (0.4%) positives detected by HSC-EM. PSD-EM detected a significantly higher number of positives compared to HSC-EM (p less than 0.05). In view of its simplicity, sensitivity and the fact that a relatively large number of specimens could be processed compared to HSC-EM, we consider that PSD-EM is a much better procedure for routine screening and diagnosis of viral gastroenteritis than HSC-EM.     

Rise per base pair in helices of double-stranded rotavirus RNA determined by electron microscopy

Regular helices of double-stranded RNA occur in nature only as the genome of certain viruses. The structure of such double-stranded RNA helices has been little studied compared to that of DNA, but some X-ray crystallographic data (Arnott, 1970; Saenger, 1984) are available. The recent advent of sequence data of bovine rotavirus RNA (Dyall-Smith et al., 1983; Elleman et al., 1983; Ward et al., 1984) has enabled us to determine by direct measurement of electron micrographs the translation, or axial distance between base pairs in RNA duplexes. Using two different spreading conditions we obtained values of 2.79 +/- 0.10 and 2.80 +/- 0.11 A. These results are consistent with the 11-fold A RNA (Arnott, 1970; Rosenberg et al., 1976) proposed for the conformation of double-stranded RNA. We included both circular and linear molecules of phi X174 RF DNA in the same preparations, and the translations for these molecules were between 3.23 +/- 0.06 and 3.29 +/- 0.05 A. Thus, double-stranded RNA contained 1.16 to 1.17 times more nucleotides per unit length than DNA.     

Close association ofPneumocystis carinii from infected rat lung with culture cells as shown by light and electron microscopy

Studies of the association of rat-originPneumocystis carinii with culture cells were performed both to learn more about the role of cells inP. carinii culture and to evaluate additional cell lines in an effort to improve culture methods. Proliferation of trophozoites ofP. carinii from rat lung in cultures with six lung cell lines was demonstrated by light microscopic evaluations of both Giemsa-stained and immune-specific-stained culture samples. Scanning electron microscopy and transmission electron microscopy were used to study the organism's interaction with culture cells and demonstrated a close association ofP. carinii with cells in cell lines that supported growth. Proliferation with the MVILU line was suboptimal and there was less organism interaction with these cells than with other cell lines that allowed proliferation. Two cell lines evaluated, Chinese Hamster ovary CHOKI and CHOLEKI, did not allow proliferation and had no association ofP. carinii with cells. Scanning and transmission electron micrographs demonstrated the close association of organisms with rat fetal lung (RFL), human embryonic lung (HEL), human diploid lung (HFL), and feline embryonic lung (AKD) culture cells. It appears that the association of rat-originP. carinii with cells is essential for parasite proliferation in short-term culture.     

Detection of human rotavirus by nucleic acid analysis in comparison to enzyme-linked immunoassay and electron microscopy

The results of RNA analysis for the detection of rotavirus were compared with those of a standard enzyme-linked immunsorbent assay (ELISA) and electron microscopy using 212 faecal specimens obtained from 200 children with gastroenteritis. Rotavirus was extracted directly from faecal specimens and RNA segments were made visible by polyacrylamide gel electrophoresis using a silver staining technique. Of the 212 faecal specimens 137 were found to be positive in ELISA, 125 in RNA analysis and 121 in both methods. Forty-nine of the 212 specimens were also investigated by electron microscopy. Thirty-five were positive when examined by electron microscopy, 37 were positive in ELISA and 33 in RNA analysis. RNA analysis of 119 faecal samples in outbreaks and sporadic cases of rotavirus infection yielded 42 different rotavirus electrophoretypes. The results indicated that no one method was sufficient to detect all positive specimens and that RNA analysis is useful in epidemiological studies.