Electron microscopic DOPA reaction test for oculocutaneous albinism

2000 ◽  
Vol 292 (6) ◽  
pp. 301-305 ◽  
Author(s):  
Y. Takizawa ◽  
Shingo Kato ◽  
Jun Matsunaga ◽  
Ryoji Aozaki ◽  
Yasushi Tomita ◽  
...  
1994 ◽  
Vol 14 (6) ◽  
pp. 443-450 ◽  
Author(s):  
Hiroshi Shimizu ◽  
Akira Ishiko ◽  
Arata Kikuchi ◽  
Masashi Akiyama ◽  
Kaoru Suzumori ◽  
...  

2019 ◽  
Vol 152 (Supplement_1) ◽  
pp. S42-S43
Author(s):  
Atreyee Basu ◽  
Surya Seshan ◽  
Luis Angel ◽  
Andre Moreira ◽  
Fang Zhou

Abstract Introduction Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive hereditary disorder characterized by oculocutaneous albinism and bleeding diathesis. Transplantation is often conducted to treat lung fibrosis, which is the most fatal complication of this disease. While the literature discusses the diagnosis of HPS based on genetic testing, radiology, and electron microscopic (EM) findings of platelet granules, there is a paucity of images in the literature illustrating the pulmonary histopathologic and EM features of HPS. Case Report Here we present striking histopathologic and EM images from a case of pulmonary fibrosis due to HPS in a 48-year-old female. The patient presented with restrictive lung disease and bilateral decreased breath sounds with diffuse crackles. She was clinically diagnosed with HPS and underwent bilateral lung transplant. On histopathology, both pneumonectomy specimens showed diffuse interstitial fibrosing and cellular pneumonitis with end-stage remodeling and type II pneumocyte (PC-II) hyperplasia. The PC-IIs had abundant foamy cytoplasm and compressed scalloped nuclei. Alveolar macrophages contained fine brown granules positive for PAS-D stain. EM analysis revealed that the PC-IIs contained numerous lamellated myelin bodies (so-called giant lamellar body degeneration) suggestive of surfactant admixed with lipid and luminal microvilli. The pigmented alveolar macrophages also contained lamellated myelin bodies, as well as clusters of single membrane-bound structures with varying size and electron density admixed with vacuolar and granular debris suggestive of ceroid deposits. Conclusion Based on light microscopy, histochemical analysis, EM, and clinical presentation, it was concluded that our findings were consistent with pulmonary changes as seen in HPS.


1999 ◽  
Vol 2 (5) ◽  
pp. 404-414 ◽  
Author(s):  
Eliezer Rosenmann ◽  
Ada Rosenmann ◽  
Zvi Ne'eman ◽  
Aby Lewin ◽  
Idit Bejarano-Achache ◽  
...  

Oculocutaneous albinism type I (OCA I) comprises autosomal recessive syndromes of hypopigmentation and low vision, caused by the lack of tyrosinase activity. Affected families seek genetic counseling and prenatal diagnosis as preventive measures. Until recently, prenatal diagnosis of OCA I was achieved by histologic and electron microscopic examination of fetal skin biopsies. Lately, a molecular genetic approach has become possible by the identification of the two mutated copies of the TYR gene, coding the tyrosinase, in which over 60 mutations have been identified. We report here our experience in prenatal diagnosis of OCA I using the two strategies. Thirty-four prenatal tests were performed in fetuses at risk for OCA I. In 31 cases the diagnosis was made in fetal scalp biopsies using the histological approach. The microscopic observations revealed normal melanogenesis in 26 biopsies. Five albino fetuses were diagnosed by the demonstration of arrest of melanogenesis in early stages I and II. In three pregnancies, molecular genetic tests were performed on DNA extracted from amniocytes, using direct mutation analysis (in one), and complemented by linkage analysis (in two). One albino and two normally pigmented fetuses were diagnosed. The prenatal molecular genetic test can be applied to families when at least one mutation is diagnosed in the albino patient. The histological approach is applicable in all families at risk for OCA I.


Author(s):  
R. A. Waugh ◽  
J. R. Sommer

Cardiac sarcoplasmic reticulum (SR) is a complex system of intracellular tubules that, due to their small size and juxtaposition to such electron-dense structures as mitochondria and myofibrils, are often inconspicuous in conventionally prepared electron microscopic material. This study reports a method with which the SR is selectively “stained” which facilitates visualizationwith the transmission electron microscope.


Author(s):  
V. F. Allison ◽  
G. C. Fink ◽  
G. W. Cearley

It is well known that epithelial hyperplasia (benign hypertrophy) is common in the aging prostate of dogs and man. In contrast, little evidence is available for abnormal epithelial cell growth in seminal vesicles of aging animals. Recently, enlarged seminal vesicles were reported in senescent mice, however, that enlargement resulted from increased storage of secretion in the lumen and occurred concomitant to epithelial hypoplasia in that species.The present study is concerned with electron microscopic observations of changes occurring in the pseudostratified epithelium of the seminal vescles of aging rats. Special attention is given to certain non-epithelial cells which have entered the epithelial layer.


Author(s):  
Glennelle Washington ◽  
Philip P. McGrath ◽  
Peter R. Graze ◽  
Ivor Royston

Herpes-like viruses were isolated from rhesus monkey peripheral blood leucocytes when co-cultivated with WI-38 cells. The virus was originally designated rhesus leucocyte-associated herpesvirus (LAHV) and subsequently called Herpesvirus mulatta (HVM). The original isolations were from juvenile rhesus monkeys shown to be free of antibody to rhesus cytomegalic virus. The virus could only be propagated in human or simian fibroblasts. Use of specific antisera developed from HVM showed no relationship between this virus and other herpesviruses. An electron microscopic study was undertaken to determine the morphology of Herpesvirus mulatta (HVM) in infected human fibroblasts.


Author(s):  
Mitsuo Ohtsuki ◽  
Michael Sogard

Structural investigations of biological macromolecules commonly employ CTEM with negative staining techniques. Difficulties in valid image interpretation arise, however, due to problems such as variability in thickness and degree of penetration of the staining agent, noise from the supporting film, and artifacts from defocus phase contrast effects. In order to determine the effects of these variables on biological structure, as seen by the electron microscope, negative stained macromolecules of high density lipoprotein-3 (HDL3) from human serum were analyzed with both CTEM and STEM, and results were then compared with CTEM micrographs of freeze-etched HDL3. In addition, we altered the structure of this molecule by digesting away its phospholipid component with phospholipase A2 and look for consistent changes in structure.


Author(s):  
J. Frank ◽  
P.-Y. Sizaret ◽  
A. Verschoor ◽  
J. Lamy

The accuracy with which the attachment site of immunolabels bound to macromolecules may be localized in electron microscopic images can be considerably improved by using single particle averaging. The example studied in this work showed that the accuracy may be better than the resolution limit imposed by negative staining (∽2nm).The structure used for this demonstration was a halfmolecule of Limulus polyphemus (LP) hemocyanin, consisting of 24 subunits grouped into four hexamers. The top view of this structure was previously studied by image averaging and correspondence analysis. It was found to vary according to the flip or flop position of the molecule, and to the stain imbalance between diagonally opposed hexamers (“rocking effect”). These findings have recently been incorporated into a model of the full 8 × 6 molecule.LP hemocyanin contains eight different polypeptides, and antibodies specific for one, LP II, were used. Uranyl acetate was used as stain. A total of 58 molecule images (29 unlabelled, 29 labelled with antl-LPII Fab) showing the top view were digitized in the microdensitometer with a sampling distance of 50μ corresponding to 6.25nm.


Author(s):  
Kazuaki Misugi ◽  
Nobuko Misugi ◽  
Hiroshi Yamada

The authors had described the fine structure of a type of pancreatic islet cell, which appeared different from typical alpha and beta cells, and tentatively considered that this third type of granular cell probably represents the D cell (Figure 1).Since silver staining has been widely used to differentiate different types of pancreatic islet cells by light microscopy, an attempt to examine this staining reaction at the electron microscopic level was made.Material and Method: Surgically removed specimens from three infants who suffered from severe hypoglycemia were used. The specimens were fixed and preserved in 20% neutral formalin. Frozen sections, 30 to 40 micron thick, were prepared and they were stained by Bielschowsky's method as modified by Suzuki (2). The stained sections were examined under a microscope and islet tissues were isolated. They were fixed in 1% osmium tetroxide in phosphate buffer for one hour and embedded in Epon 812 following dehydration through a series of alcohols and propylene oxide.


Author(s):  
F.J. Sjostrand

In the 1940's and 1950's electron microscopy conferences were attended with everybody interested in learning about the latest technical developments for one very obvious reason. There was the electron microscope with its outstanding performance but nobody could make very much use of it because we were lacking proper techniques to prepare biological specimens. The development of the thin sectioning technique with its perfectioning in 1952 changed the situation and systematic analysis of the structure of cells could now be pursued. Since then electron microscopists have in general become satisfied with the level of resolution at which cellular structures can be analyzed when applying this technique. There has been little interest in trying to push the limit of resolution closer to that determined by the resolving power of the electron microscope.


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