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.     

Light and electron microscopic investigation of parathyroid carcinoma during differentiation

Summary A case of parathyroid carcinoma in a 74-year-old female patient was studied by light and electron microscopy.The malignancy of the parathyroid tumour was confirmed by local recurrence and infiltration of adjacent structures. The tumour was composed of uniform chief cells without mitoses. Ultrastructurally, the cells were characterized by tortuous plasma membranes, numerous secretion granules, an extensive rough endoplasmic reticulum and lack of lipid vacuoles, all indicating hyperactivity, but not malignancy.At death, the autopsy revealed local recurrence of tumour tissue, but no distant metastases. Both light and electron microscopy showed that considerable dedifferentiation of the tumour tissue had occurred. The tumour cells were now characterized by a marked nuclear pleomorphism and a coarse clumping of the chromatin. The presence of secretion granules alone suggested a parathyroid origin.Thus, at death there was unequivocal histological evidence of a carcinoma, whereas no such diagnosis could be made from the early biopsy. The clinical course alone indicated the malignant nature of the lesion.     

三叉神经痛脱髓鞘改变的光镜和电镜观察

对１５例三叉神经痛患者术中撕脱的周围神经支进行光镜观察，２例进行电镜观察。可见神经纤维不同程度退行性变，肿胀、增租，轴突不规则或消失，髓鞘正常纹理不清，结构紊乱、变形，有的增生增厚呈乳头状或球状突向轴浆，有的松解、断裂呈多层状、空泡状、空网状改变，严重者出现脱髓鞘化。同时观察到三叉神经远心端病变较近心端严重，认为三叉神经的脱髓鞘改变是三叉神经痛的主要病理改变和主要病因，支持三叉神经痛的周围病原学说，并结合文献对三叉神经痛的病因、发病机制进行了讨论。     

Light and electron microscopic observation on the cervical epithelium of the rabbit. I

The light and electron microscopy of the cervical epithelium of ovulatory, estrous, and long-term ovariectomized rabbits have been studied to determine what structural changes occur under different hormonal conditions. The percentage of nonciliated secretory cells is 49.6 in ovulatory, 43.6 in estrous, and 23.7 in long-term ovariectomized rabbits, and of ciliated cells is 50.2 in ovulatory, 56.2 in estrous, and 76.3 in long-term ovariectomized animals. The values for the ovulatory and estrous rabbits are significantly different at the P <0.05 level from those of the ovariectomized animals. In all 3 groups the general ultrastructure of the normal ciliated cells is similar. Interestingly, the Golgi complex is very prominent in all. Glycogen bodies occur frequently only in ciliated cells of ovariectomized and occasionally of estrous animals. Abnormalities in cil-iation are quite common in the ovariectomized rabbits. The structure of the nonciliated secretory cells varies appreciably within and between the 3 groups. In these cells from well-developed epithelia of certain ovulatory and estrous animals, the apical cytoplasm contains secretory granules of at least three types. In addition, very irregularly shaped, dense, perinuclear granules occur, which may be another type of secretory granule or lysosomes. As compared to ciliated cells, the secretory cells have less prominent Golgi complexes, more abundant bundles of intermediate filaments, a more extensive glycocalyx on their apical surface, and more heterochromatic nuclei. In comparison to the cells of well-developed epithelia, the nonciliated cells of some other ovulatory and estrous rabbits are less well differentiated with fewer or no secretory granules and less well developed organelles. In the nonciliated cells of the long-term ovariectomized rabbits, there are no secretory or dense perinuclear granules. There is a decrease in the number of organelles that are involved in secretion, in the size of the cells, and in the amount of nuclear euchromatin.     

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。     

Membranous lipodystrophy. Light and electron microscopic study of a biopsy case

Membranous lipodystrophy is a peculiar systemic disease almost exclusively found in Japan and Scandinavia and characterized by formation of numerous membranous structures in the adipose tissue of bone marrow and soft tissue. Light and electron microscopic study of a biopsy case of the disease was presented. The membranous structures consisted of membrane and inner space on both light and electron microscopic study. The membrane consisted of two kinds of layers, dense and amorphous. The dense layer was positive for lipid stainings. The amorphous layer did not show any definite lipid constituents and was supposed to consist of an amorphous substance derived from abnormal fat metabolism of diseased fat cells, degenerative cytoplasms of the diseased cells, and/or stromal cells. It probably also had some stromal substance alteration due to membranolipodystrophic change. Accumulation of the amorphous layer in the interstitium leads to degeneration and disappearance of adjacent fat cells. This process may play a role in further advance of membranous structures.     

Light and electron microscopic demonstration of extracellular immunoglobulin deposition in renal tissue.

Extracellular immunoglobulin (IgG) deposits were shown by both light and electron microscopy in renal biopsy material using immunogold labelling. After fixation of tissue in 4% paraformaldehyde and embedding in Lowicryl K4M, semithin sections were cut and stained using the immunogold silver stain. The sections were then viewed and areas of interest were noted; ultrathin sections were cut from the same block of tissue, then stained using immunogold. Good localisation was achieved at both optical and ultrastructural levels allowing direct correlation to be made in the same area of tissue.     

Light and electron microscopic observation of intracytoplasmic inclusion bodies in the locus coeruleus of the hamster

The authors previously demonstrated that intracytoplasmic inclusion bodies (1-3 microm) in the mouse locus coeruleus under light and electron microscopy are characteristically stained using the Holmes modified method. We reported that one inclusion body existed in almost all neurons of the locus coeruleus. The present study examined whether similar inclusion bodies are present in the Syrian hamster (weight, about 60 g). Paraffin sections stained with the modified Holmes' method dis played numerous small inclusion bodies in the cytoplasm of cells in the locus coeruleus. Epon sections (1 microm thick) stained using toluidine blue were observed under light microscopy, and numerous small inclusion bodies were again observed. Under electron microscopy observation, inclusion bodies (<1 microm in diameter) predominantly comprised small granular materials, similar to those described by previous investigators. Although inclusion bodies were devoid of a limiting membrane, the relation ship to cytoplasmic organelles was unclear. However, free and polyribosomes were occasionally noted in close proximity to inclusion bodies. Inclusion bodies may thus be formed from ribosomes. Intracytoplasmic inclusion bodies in the hamster locus coeruleus differed in appearance compared with inclusion bodies in the mouse locus coeruleus.     

Light and electron microscopy of parathyroid carcinoma

Summary The morphology of three cases of parathyroid carcinoma is described, including the electron microscope findings in two of these cases. The clinical and morphologic points for the tentative diagnosis of parathyroid carcinoma are discussed. The malignancy of a parathyroid tumour is proved by lymphogenic or hematogenic metastases, by histological evidence of tumour infiltration into the surrounding tissues (including macroscopic adherence and sometimes vocal cord paralysis), and by cytologic evidence of mitoses. Nuclear atypism is often present but is neither a necessary nor an adequate proof of malignancy, because it is also seen in benign adenomas and in hyperplastic parathyroids. The ultrastructure of the carcinoma cells was also characterized by nuclear atypism and mitoses. In one carcinoma, the contents of cytoplasmic organelles varied in different cells, indicating various endocrine activity of the tumour cells. In another parathyroid carcinoma with low endocrine activity, copious cytoplasmic organelles and many secretory granules were found. There seem to be three possible causes of non-functioning parathyroid carcinomas: 1. lack of hormone synthesis, 2. impairment of cellular hormone secretion, 3. synthesis of a pathologic protein with defective endocrine activity.Supported by DFG, Sonderforschungsbereich 34 Endokrinologie.     

Malignant fibrous histiocytoma with granular cells, mimicking a granular cell tumor. Light, electron microscopic and immunohistochemical observation of a case

The tumor that occurred subcutaneously in the left hypochondriac region of an 87-year-old female is reported. Light microscopically, this tumor was composed of two kinds of cells, spindle cells and granular cells. The spindle cells showed various pictures such as fascicular arrangement, pleomorphic giant cells in the myxoid stroma and areas with abundant blood vessels. The granular cells contained PAS positive and diastase-resistant granules, and these granules, being electron microscopically phagocytic lysosomes, showed the same findings as the granules seen in the granular cell tumor. The immunohistochemical studies for S-100 protein, neuron specific enolase, CEA, myoglobin, and lysosome were negative, but alpha-antichymotrypsin was positive. From the microscopic and immunohistochemical findings, this tumor was diagnosed as a malignant fibrous histiocytoma with granular cell changes of tumor cells.     

Nephrogenic adenoma: a light and electron microscopic and immunohistochemical study

Nephrogenic adenoma is a relatively infrequent lesion that involves the bladder, the ureters, and the urethra. Even though several cases have been described since the early 1950s, the etiopathogenesis of the lesion is still uncertain. Electron microscopic and immunohistochemical studies seem to favor a congenital origin.     

A case of lipoprotein glomerulopathy. Light and electron microscopic observations of the glomerulus

A 41-year-old Japanese woman with lipoprotein glomerulopathy is reported. The patient presented with nephrotic syndrome, hyperlipoproteinemia and an increased level of plasma Apo E. The damaged glomeruli showed various degrees of capillary dilatation and accumulation of some material-often showing stratification, along with mesangial proliferation and mesangial interposition. The accumulated material was stained positive for beta-lipoprotein by the indirect immunoperoxidase technique. Capillary dilatation resulted from gradual accumulation of the lipoprotein as well as destruction of the mesangium, as if being torn off, due to increased intraluminal pressure. The patient's eldest sister also suffers from the same renal disease, suggesting a hereditary predisposition.     

Intrathyroidal water-clear cell parathyroid adenoma: a case report

Adenomas of the parathyroid gland, the majority of which contain mixed cell populations, are the most frequent cause of primary hyperparathyroidism. Parathyroid adenomas composed exclusively of water-clear cells are exceptionally rare. Until now, only 2 cases have been reported in English literature. We report a water-clear cell adenoma of the parathyroid gland in an intrathyroidal position, which has not been described previously according to our knowledge.