Desmin myopathy with cardiomyopathy

We report a case of abnormal desmin accumulation within the muscle of a 30-year-old female with a 2-year history of cardiomyopathy and axial muscle weakness. Serum creatine kinase was normal. A quadriceps muscle biopsy revealed pink hyaline inclusions, which stained for acid phosphatase and with PAS and were present in both fibre types. Electron microscopy showed these inclusions to consist of aggregates of irregularly arranged 6-to 15-nm-diameter filaments enmeshed within a central core of dense granulo-amorphous material. In other areas, the granulo-amorphous material lay as irregular patches within the sarcoplasm, mainly at the level of the Z band causing disruption of the sarcomere. Immunoelectron microscopy using colloidal gold showed that the dense amorphous material reacted strongly with desmin antisera and could, therfore, represent a defective or phosphorylated form of the protein.     

The enlarging spectrum of desminopathies: new morphological findings, eastward geographic spread, novel exon 3 desmin mutation

A 52-year-old man, who had developed distal muscle weakness in legs and arms, was found to have distal muscle atrophy as well as cardiac arrhythmia. His 10-year younger brother developed restrictive cardiomyopathy at the age of 20 years, which required cardiac transplantation at the age of 41 years. Skeletal muscle biopsy specimens of the older brother revealed granulofilamentous material and plaques containing numerous proteins, foremost desmin, as did cardiac biopsy tissue. The explanted heart of the younger brother showed similar protein-rich plaques and granulofilamentous material within cardiac myocytes. A novel heterozygous Glu245Asp (E245D) missense mutation in exon 3 of the desmin gene (DES) at 2q35 was found in the older brother. While clinical data and muscle biopsy pathology of the older brother conform to the nosological spectrum of desminopathies, the early-onset cardiomyopathy, a similar cardiac pathology as in skeletal muscle tissues and a novel missense mutation in the DES gene, enlarge the nosological spectrum of desminopathies.     

An unusual familial cardiomyopathy characterized by aberrant accumulations of desmin-type intermediate filaments

Summary Immunofluorescence microscopy using antibodies specific for different intermediate filament types has been used to study a rare familial cardiomyopathy characterized electron microscopically by massive accumulations of unordered intermediate filaments. The results show that the inclusions in cardiac muscle cells are composed of the desmin type of intermediate filament characteristic of muscle tissues, and draw attention to the importance of these filaments in maintaining normal cardiac ultrastructure and function.     

Cytology of embryonal rhabdomyosarcoma: a cytologic, light microscopic, electron microscopic, and immunohistochemical study of seven cases

A correlated cytologic and histologic study of seven cases of embryonal rhabdomyosarcoma is presented. The diagnosis of rhabdomyosarcoma was established by light and electron microscopy and immunohistochemistry of the operative specimens. The cytologic appearance of the smears corresponded well with the histopathologic findings. Cytologically, two main cell types were distinguished: a predominant primitive, small round cell with scant cytoplasm and a large cell with an abundant cytoplasm, sometimes tadpole- or ribbon-shaped. The tumor cells were often enclosed in a background of mucosubstances. The lack of cytologic features proving rhabdomyoblastic differentiation, such as cross-striation, necessitates the use of additional methods in the cytologic diagnosis of embryonal rhabdomyosarcoma. The value of the embedding technique for ultrastructural analysis and immunohistochemistry in the demonstration of desmin in aspirates is emphasized in the diagnosis of embryonal rhabdomyosarcoma.     

Immunohistochemistry of the human ductus epididymis

Our objective was to characterize epithelial cells, lamina propria, and sites of estrogen coupling in the caput, corpus, and cauda regions of the human epididymis using antibodies to cytokeratin types; epithelial membrane antigen; laminin; type IV collagen; vimentin; desmin-, and estradiol-receptor-related protein; and immuno-histochemical techniques. Principal cells immunostain by both AE1/AE3 antibodies (keratins 1–8, 10, 13–15, and 19) and anti-pan-keratin antibodies (keratin 5, 6, and 8). Immunoreactions to both anti-keratin antibodies increase from the caput to the cauda epididymis. The principal cells only immunostained by antikeratin 19 antibodies in the cauda and showed no reaction to keratins 10 and 11. Basal cells and apical cells immunoreact to anti-AE1/AE3, antipan-keratin, and antikeratin 19 antibodies, but not to antikeratin 10 and 11 antibodies, in all three epididymal regions. The principal cells immunoreact with epithelial membrane antigen antibodies in the stereocilia and subjacent cytoplasm. This immunostaining decreased from the caput to the cauda. Antivimentin antibodies stained the apical cytoplasm of principal cells and limited areas of both principal cells and basal cells. This immunoreaction decreased from the caput to cauda. Apical cells immunostained in the three regions. Immunoreaction to ER-D5 was moderate in the principal cells, basal cells, apical cells, and muscular coat cells in the cauda. The apical cells immunostained in the three regions. Antilaminin antibodies stained the epithelial basement membrane in the three regions. Type IV collagen was detected in the basement membrane as well as around the muscular coat cells in the three regions. Immunoreaction to desmin was intense in the muscular coat cells in the three regions. Thickness of the immunostained area for both type IV collagen and desmin increases from the caput to the cauda. The differences in immunostain pattern along the epididymis length seem to be related to regional differences in function. © 1993 Wiley-Liss, Inc.     

Desmin and actin associated with cytoplasmic bodies in skeletal muscle fibers: immunocytochemical and fine structural studies,with a note on unusual 18- to 20-nm filaments

Summary In a fine structural and immunocytochemical study, the latter performed on semithin sections of epoxy resin embedded skeletal muscle fibers, three types of cytoplasmic bodies were identified in a case of cytoplasmic body myopathy: (1) The first type, the classical type, showed a central core and a light halo with radiating actin filaments at the periphery. (2) The second type, the spheroid body was characterized by irregularly arranged granular masses associated with intermediate filaments. Desmin immunoreactivity occurred in the central and peripheral parts, where filaments of intermediate size were visualized by electron microscopy. Desmin immunoreactivity was noted also at the Z-bands of striated annulets, within areas of disordered myofibrils, such as sarcoplasmic masses, and in atrophic muscle fibers. (3) The third type of the cytoplasmic body was composed mainly of large masses of uneven granularity and electron density. The center of this type reacted to anti-actin antibody suggesting that the 5- to 6-nm filaments, which ultrastructurally proved to be a major component, were of the actin type. By contrast, neither intermediate filaments nor actin microfilaments were found by electron microscopy in cytoplasmic bodies in a second case where no immunoreaction to desmin or actin occurred. Anti-vimentin antibody stained only the cytoplasm of endomysial cells, but not the inclusion bodies. Some other, unusual inclusions with 18- to 20-nm tubulo-filamentous structures have to be distinguished from the various types of filaments in cytoplasmic bodies. It is concluded, that pleomorphism and heterogeneity of cytoplasmic bodies have to be taken into consideration when classifying cytoplasmic body myopathies.Recipient of a grant from the Deutsche Forschungsgemeinschaft.     

大鼠心肌缺血再灌注后结蛋白的变化

目的：探讨缺血再灌注损伤后大鼠心肌细胞内结蛋白分布状况与含量的变化。方法：30只成年健康雄性SD大鼠,随机分为缺血组、缺血再灌注组及假手术组。缺血组实施手术结扎冠状动脉30 min后即刻取材,再灌注组缺血后再灌注120 min后取材,假手术组实施同样的手术过程但不结扎。应用免疫荧光标记技术和图像定量分析方法对大鼠心肌细胞结蛋白分布及含量的变化进行研究。结果：缺血组和缺血再灌注组心肌结蛋白在心肌细胞内的分布较假手术组的有序分布发生改变,变得无序而紊乱,心肌纤维横纹不再清晰,变得断续而模糊。缺血组和缺血再灌注组心肌结蛋白含量显著低于对照组（P〈0.05）,缺血再灌注组显著低于缺血组（P〈0.05）。结论：心肌缺血和缺血再灌注均可造成心肌细胞结蛋白发生不同程度的降解,使心肌细胞骨架结构继发破坏,这可能是心肌机械功能异常的解剖学基础。