Web-based virtual microscopy in teaching and standardizing Gleason grading

Gleason grading forms the basis of prognostic and therapeutic assessment in prostatic carcinoma despite its subjective nature and substantial interobserver variation. The accuracy of Gleason grading can be improved by the use of educational tools such as reference images. However, conventional microscopy images are of limited educational value because it is neither possible to view the sample at different magnifications nor to navigate into different areas of the specimen. This limitation can be overcome by the use of virtual microscopy, which allows viewing entire digitized microscope slides. We created an interactive Web site ( www.webmicroscope.net/gleason ) featuring a comprehensive set of prostatic needle biopsies as virtual slides, which can be viewed with a standard Web browser (Internet Explorer or Netscape). To evaluate the validity of Web-based virtual microscopy for Gleason grading, an experienced uropathologist (TK) scored a series of 62 biopsies from the original glass slides and 6 weeks later from virtual slides on the Web site using an ordinary desktop computer. The intraobserver agreement was excellent, with identical Gleason scores found in 48 of the 62 cases ( kappa = 0.73). The 14 remaining scores differed only by 1 point on the Gleason scale (2-10). The virtual slides were viewed by 2 other uropathologists (PM and HH), with interobserver kappa coefficients ranging from 0.55 to 0.62, which is within the range of previously reported studies using glass slides. The 3 uropathologists' Gleason scores were included as reference scores on the Web site, which now serves as a publicly open platform for self-testing and learning of Gleason grading. We conclude that Web-based virtual microscopy is a promising new tool for teaching and standardizing Gleason grading.     

Immunoelectron microscopic localization of carcinoembryonic antigen in gastric adenocarcinoma cell lines

The distribution of carcinoembryonic antigen (CEA) in human gastric adenocarcinoma cell lines (HPE-GAC-3 cells and HPE-GAC-2 cells) was determined immunohistochemically by indirect peroxidase-labeled antibody method at the light and electron microscopic levels. In GAC-3 cells that proliferated as non-adherent single cells, CEA was located in the perinuclear spaces, the endoplasmic reticulum, Golgi apparatus, vesicles, multivesicular body (MVB) and entire plasma membrane. Membrane CEA was shown to be internalized into MVB in GAC-3 cells. In GAC-2 cells that form an acinus, CEA was predominantly present along the microvilli of the lumina) surface and in glycocalyceal bodies, the vesicles which bud from the microvilli into the lumen. These results suggest that in poorly differentiated cancer cells CEA is transported over the entire cell surface, retained on the membrane and accumulated Into the cell by way of the MVB, but in well differentiated cancer cells the newly synthesized CEA is rapidly and predominantly transported to the luminal surface and rapidly released from the membrane into the lumen by way of the glycocalyceal body.     

白发与黑发的微量元素分析

本文应用EPM-810Q电子探针,对53例35～60岁健康成年人白发与黑发(指长在同一部位、相邻单根白发与黑发),进行微量元素分析,结果表明:白发中Mg、Al、Cd、Ca、Cr、Mn、Fe、Se微量元素含量明显小于黑发,而Cu、Zn、Pb元素含量大于黑发。以上差异有显著性意义(P<0.001),并对上述差异进行了讨论。     

Niemann-Pick disease

Summary The results of a complex analysis of liver tissue are presented (four biopsy and two autopsy samples) obtained from six patients with Niemann-Pick disease (NPD) with a gross deficiency of sphingomyelinase (SMase) accompanied by a typical increase in sphingomyelin (SM). There were five cases of NPD type A (four of them with an atypical, prolonged course) and one case of type B. By means of lipid histochemistry it was possible to demonstrate SM storage both in hepatocytes and in the reticuloendothelial system (RES) of the liver (Kupffer cells and portal macrophages) and to show in two siblings with NPD type A a so-far undescribed centrilobular storage pattern. Enzyme histochemistry revealed a secondary deficit of nonspecific esterase activity and acid -galactosidase in liver storage macrophages and varying degrees of suppression of hepatocytic enzyme activities as a reaction to lipid storage of sudden onset. Ultrastructurally, it was possible to demonstrate cholesterol in lysosomes by using digitonin fixation, the involvement of Ito cells in lipid storage, the aggregation of storage lysosomes with certain other organelles and their occasional connections with the endoplasmic reticulum. The problems of possible lipid extraction during processing were considered as a cause of pronounced lysosomal electron-lucidity and of the ultrastructural identification of the participating lipopigment. The significance of the findings is discussed in relation to the existing classification and, particularly, to the stored lipid dilemma of cases of NPD type C.     

Ultrastructural Morphometric Study of Follicular Center Lymphocytes: II. Analyses of Cleaved-Cell Populations Do Not Support the Lukes-Collins' Concept

Ultrastructural morphometric analysis was carried out on six cases of lymph node biopsies with reactive hyperplasia to establish the frequency and depth of invaginations in nuclear profiles situated in the mantle zones and follicular centers. The frequency distribution of the depth of invaginations was similar in nuclear profiles whether in the small lymphocytes of mantle zones or the small, partially transformed (centrocytes) and fully transformed (centroblasts) lymphocytes of follicular centers. Invaginated and cleaved lymphocytes were not confined to the partially transformed (centrocytic) lymphocytes of follicular centers, and nuclear profiles with invaginations bore no resemblance to those depicted in the Lukes-Collins model. A considerable proportion of mantle zone lymphocyte nuclear profiles had invaginations (ranging from 7.5% to 53.6%) and there was no difference between the frequency of deep indentations or clefts in mantle zone lymphocytes (8.1 ± 5.4%) and the small unstimulated (9.3 ± 5.3%) and partially transformed (8.4 ± 1.4%) lymphocytes in follicular centers. Computer modeling of stylized nuclei with conical indentations indicated that all lymphocytic nuclei likely have multiple invaginations or groove-like creases.     

Atypical Glomus Tumor in the Mediastinum: A Case Report with Immunohistochemical and Ultrastructural Studies

A case is reported of atypical glomus tumor occurring in the posterior inferior mediastinum of a 26-year-old woman complaining of severe back pain. The tumor was composed of atypical small, round tumor cells with scattered mitotic figures. In addition to sheet-like, diffuse proliferation of the tumor cells, some areas of the tumor contained small “glo-moid” cells arranged in organoid and hemangiopericytoma-like patterns. Immunohistochemically, many tumor cells were positive for muscle-type actins and a few cells were focally positive for desmin. Ultrastructural studies revealed smooth muscle features of tumor cells, that is, pinocytotic vesicles, external laminas, dense plaques, and occasional thin filaments with dense bodies. The patient remained well for 5 years and 4 months after the operation without additional radiation and chemotherapy. The tumor was diagnosed as an atypical, or low-grade malignant, glomus tumor morphologically. It seems important to recognize the presence of this type of tumor in sites other than extremities and to differentiate it from other malignant small, round cell tumors.     

Juvenile hyaline fibromatosis: A report of two unrelated adult sibling cases and a literature review

Two unrelated adult sibling cases (36- and 32-year-old females) of Juvenile hyaline fibromatosis are presented. The parents of one of these patients were non-consanguineous but natives of a small Island, and one elder sister among four siblings was affected with the same disease. The parents of the other patient were consanguineous, and one other sibling suffered from the identical disease. Both patients presented with multiple subcutaneous nodules, which they had had since infancy, and had undergone numerous surgical excisions. Light microscopy examination of skin lesions from both patients showed identical histology; an abundance of a homogenous, amorphous, eosinophlllc extracellular matrix in which spindle-shaped cells were embedded. Electron microscopically, the spindle-shaped cells had hypertrophic Golgi apparatus and dilated, rough endoplasmlc reticulum. Fine flbrillar and granular material-filled structures, the contents of which were occasionally released into the extracellular matrix, were also seen, immunohistochemically, the spindle-shaped cells were vlmentin-positive but negative for α-smooth muscle actln and S-100 protein, and the hyaline ground substance was positive for type I and type III collagen but negative for type II and type IV collagen and tenascin. Matrix metalloprotelnase-1, -2, and -9, and tissue inhibitor of matrix metalloproteinase (TlMP)-2 was positive but TIMP-1 was negative. A review of 39 cases of juvenile hyaline fibromatosis In the literature is also presented. In summary, skin lesions may be the most outstanding symptoms of juvenile hyaline fibromatosis, but joint contracture and gingival hypertrophy precede the skin manifestation.     

Balloon cell nevus of the soft palate: an immunohistochemical and ultrastructural study

An ultrastructural analysis of oral balloon cell nevus of intramucosal type complemented with an immunohistochemical study was performed for the first time. The lesion was composed of large balloon cells with an admixture of small nevus cells and melanophages at the periphery. Balloon cells showed cytoplasmic accumulation of vacuoles of varying sizes and the presence of microgranular and vacuolated melanosomes were found. Residual cytoplasm contained no identifiable organelles. A spectrum of transitional forms between balloon cells and conventional nevus cells with microvacuoles was readily observed. Both cells exhibited intense immunoreactivity to multiple melanocytic markers. Ballooning phenomenon was not evident in melanophages containing a large amount of melanosome complex. It can be inferred, from the present and previous observations, that progressive vacuolization of melanosomes in nevomelanocytes may be responsible for the formation of peculiar ballooning appearance, suggesting an aberrant melanogenesis.     

Effect of peripheral axotomy on the fine structure and histochemistry of the Rolando substance: Degenerative atrophy of central processes of pseudounipolar cells

Summary Disappearence of fluorid-resistant acid phosphatase activity from the ipsilateral Rolando substance after transection of the peripheral nerve, is shown to be due to the cessation of enzyme supply from dorsal root ganglion cells to their central terminals. This is accompanied by (or ensues in consequence of) a fine structural derangement of these terminals (degenerative atrophy). Fine structural alterations of axon terminals undergoing degenerative atrophy, though similar to some extent to those seen during early phases of a Wallerian degeneration, are markedly different. Also myelinated nerve fibers, both in the dorsal horn and in dorsal columns, are affected by degenerative atrophy. This important, new trophical feature of sensory ganglion cells suggests a delicate metabolic balance between peripheral and central axonal branches of bipolar (pseudounipolar) cells. Degenerative atrophy raises serious implications in evaluating hodological experiments based upon Wallerian degeneration and offers new perspectives for theoretical and clinical neurology.     

The thymus is a site of mast cell development in chicken embryos

Thymic mast cells were studied by light and transmission electron microscopy in chicken embryos during organogenesis. Mast cells made their first appearance at day 15. At days 16 and 17, there was a burst of mast cell development with a peak of 278 ± 54 cells/mm² at day 16. Then, mast cell density decreased until hatching. During the whole embryonic period, about 80% of mast cells localized to the thymic medulla. In the cortex, they were less numerous, and some rare mast cells could be identified in the capsule and septa. Thymic mast cells could be recognized in association with hematopoietic foci, but frequently they grew independently from areas of hematopoiesis and appeared as single cells interspersed among thymocytes, thymic epithelial cells, and interdigitating cells. They were often recognized in close relationship with the scanty and delicate extracellular matrix of the developing gland. Viewed by electron microscopy, mast cells were relatively small cells, with a few secretory granules. Exocytosis was never seen, but, notably, granules emptied in a piecemeal degranulation fashion. This study demonstrates that the chicken thymus is a site of mast cell development during embryogenesis. The high mast cell density we found suggests a possible role for these cells during thymus organogenesis.