Light and electron microscopic features of a pituitary adenoma in Nelson's syndrome.

Electron microscopy of an amphophil pituitary adenoma surgically removed from a 51-year-old woman who had Nelson's syndrome revealed that the tumor was composed of melanocorticotroph cells. This finding is consistent with the view that in the human pituitary gland one single cell type produces both adrenocorticotropic hormone (ACTH) and melanocyte-stimulating hormone (MSH). In contrast to the ultrastructure of pituitary adenomas associated with Cushing's syndrome, no or only very few microfilaments were detected in the cytoplasm of the tumor cells, suggesting that adrenocortical steroids are required for the formation of microfilaments. The presence or absence of microfilaments in the tumor cells may be regarded as a distinguishing ultrastructural feature between Cushing's syndrome and Nelson's syndrome. It appears that changes in the level of circulating corticoids may affect the ultrastructural features of melanocorticotroph cells not only in normal pituitaries but also in adenohypophyseal adenomas.     

Coexistent yellow nail syndrome and selective antibody deficiency.

BACKGROUND: Yellow nail syndrome (YNS) is a rare, often underdiagnosed condition of unknown origin. The clinical features of the syndrome include yellow nails, chronic sinusitis, bronchiectasis, pleural effusion, and lymphoedema. Despite the frequent occurrence of upper and lower respiratory tract infections in patients with YNS, comprehensive analysis of their humoral immunity has not been previously reported. OBJECTIVE: To present the case of a patient with YNS whose recurrent upper and lower respiratory tract infections may have been caused by an underlying selective antibody deficiency that manifests as impaired IgG antibody response to polysaccharide antigens. METHODS: The patient underwent cultures of purulent sputum for Streptococcus pneumoniae and Haemophilus influenzae, bronchial washings for H. influenzae, and nail scrapings for fungi. Her serum levels of IgG, IgA, IgM, IgG subclasses, and serum titers of IgG antitetanus toxoid, anti-H. influenzae, and anti-S. pneumoniae antibodies were measured. RESULTS: Cultures of purulent sputum were positive on multiple occasions for S. pneumoniae and H. influenzae and bronchial washings were positive for H. influenzae. Nail scrapings were consistently negative for fungi. She had no reductions in serum levels of IgG, IgA, IgM, or IgG subclasses and had normal serum titers of IgG antitetanus toxoid antibodies. However, she demonstrated impaired IgG antibody responses following immunization with Pneumovax and an H. influenza B vaccine. CONCLUSIONS: This case report describes the first comprehensive analysis of humoral immune function in a patient with YNS. The finding of a selective antibody deficiency in our patient provides a potential explanation for the occurrence of respiratory infections in YNS. Accordingly, we recommend that functional antibody determinations and quantitative serum immunoglobulins be evaluated in patients diagnosed as having this unusual, enigmatic syndrome.     

格林-巴利综合征患者腓神经病变的光镜和电镜观察

目的：探讨格式－巴利综合征腓神经活检的光,电镜表现与临床诊断及预后的关系。方法;对２６例ＧＢＳ患者腓神经活检进行了光镜及电镜观察。结果;有髓神经纤维的呈不同程度的减少,退行性变及脱髓鞘,在病变早期髓鞘改变呈松解,变形,断裂及多层状,部分增厚突向轴浆向。     

Elastin in adenomatoid tumor. Light microscopic and electron microscopic study.

Elastin distribution was examined in adenomatoid tumors of the human genital tract. Two distinct patterns were identified: strongly positive or completely negative for elastin in the stroma, according to the case. Even in cases appearing to have very similar histologic features, the stroma was rich in elastin in some cases and was almost devoid of elastin in others. Electron microscopic examination with tannic acid staining revealed that the elastin in the stroma was composed mainly of amorphous material surrounded by a small amount of microfibrils and abundant collagen fibers. Fibroblasts were sparsely distributed in the stroma. Tumor cells displayed mesothelial cell-like features, such as abundant microvilli on the surface, numerous cytoplasmic organelles, several well-developed basal lamina. In some areas, elastin seemed to be formed by mesothelial cells. In some adenomatoid tumor cases, elastogenesis would be enhanced by activated mesothelial tumor cells as well as stromal fibroblasts.     

Intestinal spirochaetosis. Light and electron microscopic study

24 cases of colon spirochaetosis have been studied by light and electron microscopy. This condition, although rarely diagnosed because of the absence of special clinical symptoms, seems to be a rather frequent histologic finding with marked variation in its geographical incidence. In our material the incidence of spirochaetosis was 16.5%, almost double than in Great Britain.     

Meningioma of the scalp. Light and electron microscopic observations

Meningiomas occurring in the skin are rare and may be difficult to recognize on frozen section. We found intraoperative cytologic smears helpful in identifying the characteristically bland nuclei, cellular whorls, and psammoma bodies that are typical of the light microscopy of meningiomas in the CNS. This case (a scalp lesion) was also examined ultrastructurally. Cutaneous meningiomas are histologically and ultrastructurally identical to their meningeal counterparts and must be approached with caution surgically.     

Lymphomatoid granulomatosis. Light microscopic, electron microscopic and immunohistochemical study

A case of lymphomatoid granulomatosis (LYG) involving the lungs, skin, stomach, and possibly the left kidney in a 60-year-old man is presented. The infiltrates in the lungs, stomach, and skin showed a polymorphic appearance, and consisted predominantly of lymphocytes of mature and blastic form and of a few neutrophils, plasma cells, and histiocytes. Most lymphoid cells showed irregularly shaped nuclei and clustered dense bodies, characteristics indicative of T lymphocytes. An immunohistochemical study confirmed the T cell origin of the lymphocytes; i.e. they were positive for Leu-1, Leu-3a and Ia-like antigens but negative for Leu-2a antigen and the antibodies against light chains. The homogeneity of the major population of infiltrates in LYG indicates that at least some forms of LYG may be neoplastic or pre-neoplastic lymphocytic disorders which may ultimately progress to malignant lymphoma.     

Light microscopic and electron microscopic features of cyclosporine nephrotoxicity in rats.

In order to clarify morphologic changes associated with cyclosporine (CS) nephrotoxicity, CS in ethyl alcohol at 25 mg/kg/day i.p. was administered to male Sprague-Dawley rats for periods of 1 to 8 weeks. Mean systolic BP was slightly increased in the CS group at 4 weeks (p < 0.05), but there was no difference compared to a control group at 8 weeks. Blood urea nitrogen was significantly elevated at 4 weeks and continued to rise (p < 0.005), whereas serum creatinine was elevated at 8 weeks. Microscopic examination of the kidneys from CS-treated rats at one week revealed cytoplasmic vacuolization in all segments of the proximal tubules, tubular inclusion bodies, and peritubular capillary congestion. Ultrastructurally, some vacuoles were neutral fat droplets, while others appeared as single membrane-bound structures due to dilatation of the endoplasmic reticulum. The tubular inclusion bodies were enlarged autolysosomes filled with distorted mitochondrial fragments. At two weeks, tubular regeneration was prominent, in addition to the above mentioned toxic tubulopathy. At four weeks, focal areas of interstitial fibrosis and tubular atrophy associated with cystic dilatation were seen. At 8 weeks, interstitial and intratubular microcalcification were present, in addition to patchy foci of interstitial fibrosis, but vascular lesions were not demonstrated. Although renal tubular changes characterized by vacuolization, inclusion bodies, and microcalcification and interstitial fibrosis are not specific for CS toxicity, these changes are commonly found in both humans and rats at high doses of CS.     

Light and electron microscopic features of tropical ulcer.

The histopathological features of 20 tropical ulcers with the electron microscopic findings on seven biopsy specimens are reported. The main findings were loss of epidermis associated with extensive dermal oedema, infiltration by polymorphonuclear leucocytes, and disruption of collagen bundles. The presence of micro-organisms at the site of tissue damage was shown and compared with the morphology of the organisms grown in culture. The most commonly identified bacteria were pleomorphic rods whose electron microscopic appearances accorded most closely with Fusobacteria grown in vitro. Spirochaetes, identified ultrastructurally as Treponema sp, were also present. There was no evidence of vasculitis to explain the rapid onset of ulceration, but necrotic changes seen in the dermis and the inflammatory cell infiltrate suggest that, associated with cell necrosis, bacteria previously shown in vitro have an important role in the pathogenesis of tropical ulcers.     

Acute radiation nephritis. Light and electron microscopic observations.

Light and electron microscopy were used to observe acute radiation nephritis. By light microscopy the changes were of fibrinoid necrosis of the arteries and atrerioles with segmental necrosis of the glomerular tufts. By electron microscopy the endocapillary cells reacted by hypertrophy and hyperplasia with increase in cytoplasmic organelles. In addition, disruption of endothelial and epithelial cells from the basement membranes were seen. It is concluded that the electron microscopic changes were unique and may be helpful in differentiating the necrotizing glomerulitis seen in other conditions, especially malignant hypertension.     

Light and electron microscopic studies of the pulmonary alveolar surfactant.

22 methods of light and electron microscopy have been tested for the identification of the pulmonary alveolar surfactant. Among the non electron microscopic methods Romhányi's anisotropic staining with toluidine blue was the most serviceable. In addition to simple performance it allows the identification of the smallest alteration -- not to be identified by other methods -- of the alveolar surfactant. Among the electron microscopic technics Ruthenium Red staining and Dermer's tricomplex method yielded the best results. Given that different chemical components of the alveolar surfactant will be identified by these 2 methods they supplement each other favourably. In the study of human cadaver material Baker's phospholipid reaction and Romhányi's anisotropic toluidine blue reaction is being used.     

Primary semimalignant Schwannoma of the liver. Light and electron microscopic studies

The light and electron microscopy study of a so-called low grade or semimalignant Schwannoma in the liver of a 74 year-old white man without von Recklinghausen's disease is reported. The diagnosis relied on the histological findings of numerous moderately pleomorphic fusiform cells with hyperchromatic nuclei, areas of necrosis, the local infiltrative pattern with absence of metastasis at autopsy, the huge size (21 X 12 X 8 cm) and the clinical data of rapid growth pattern associated with marked body weight loss. The proper identification in surgical specimens of this kind of neoplasias would lead to more appropriate therapeutic approach.     

The olfactory region of the bat Scotophilus heathi. Light and electron microscopic studies]

The present investigation reports light and electron microscopical aspects of the main olfactory epithelium (MOE) of the insectivorous bat Scotophilus heathi. Serial frontal sections of the nose and associated structures reveal: 1) that the MOE is located on most of the ethmoturbinals and on the proximal upper portion of the nasal septum; and 2) that the vomeronasal organ is absent in this species. The ultrastructure of the MOE of Scotophilus heathi is similar to that observed in other vertebrates. Moreover, we did not observe significant morphological differences between the MOE of male and female animals. Nevertheless, the supra-nuclear region of the supporting cells of males and females shows a different amount and distribution of "lysosome-like" cell organelles at the two times of the year investigated.