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Ultrastructural Evaluation (ultrastructural + evaluation)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Transepithelial elimination of cutaneous vulval granuloma inguinale

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 10 2000
Pratistadevi K. Ramdial
Background: Transepithelial elimination (TEE), a distinct and well-known entity, is a process during which the skin eradicates undesirable or irritative dermal substances through intact epidermis or follicular epithelium by passive or active means. Although TEE is being described in an increasing number and range of pathological processes, to date, TEE of granuloma inguinale (GI) remains unrecorded in the English-language literature. The aims of this study were: 1) To appraise the light microscopic and ultrastructural morphological epidermal changes that are associated with TEE of cutaneous vulval GI; and 2) To determine the role of intra-epidermal leucocytes and histiocytes in the pathogenesis of TEE of vulval GI. Methods: This is a retrospective 9-year histopathological review of all cases diagnosed and coded as vulval granuloma inguinale in the Department of Anatomical Pathology, Nelson R. Mandela School of Medicine, University of Natal, Durban, South Africa. Ultrastructural evaluation was performed on selected cases using a Jeol transmission electron microscope. Results: Of 53 skin biopsies from 47 patients with vulval GI, 43 were suitable for the study. The age range of patients was 15,40 years (mean age=22 years). There were eleven papular, twelve nodular, seven verrucous and thirteen ulcerative lesions. Donovan bodies within macrophages, free-lying Donovan bodies and dense aggregates of neutrophils and plasma cells were seen in the dermis of all biopsies. There was consistent overlying pseudoepitheliomatous hyperplasia. The dermal inflammatory infiltrate hugged the dermo-epidermal junction and appeared entrapped between elongated and acanthotic epidermal rete ridges and pegs. Transepidermal neutrophil microabscesses, histiocytes containing Donovan bodies and neutrophilic and histiocytic fragmentation were present. A variable number of free-lying and intra-histiocytic Donovan bodies and neutrophils were present on the surface of the epidermis. On ultrastructural investigation epidermal spongiosis, intracellular oedema, free-lying, intra-neutrophilic and intra-histiocytic Donovan bodies, and intact and degenerating neutrophils and histiocytes were evident between keratinocytes. The degenerative histiocytes demonstrated marked vacuolation, mitochondrial swelling and bacilli within phagolysosomal vacuoles, bound by intact or disrupted limiting membranes. Conclusion: The inflammatory infiltrate at the epitheliomesenchymal interface, pseudoepitheliomatous hyperplasia, intra-epidermal accumulation and disintegration of neutrophils and histiocytes, and the associated release of lytic enzymes, play important contributory roles in TEE of GI. TEE of infectious agents is a poorly recognised mechanism of spread of infectious diseases and represents a public health hazard. In cutaneous vulval GI, TEE is highlighted as a hitherto unrecognised, potential method of spread of Calymmatobacterium granulomatis. [source]

Iron localization in superficial siderosis of the central nervous system

NEUROPATHOLOGY, Issue 2 2009
Harry Kellermier
Originally conceived as an uncommon disorder, with the advent of MRI, CNS superficial siderosis has been observed more frequently. We present histologic, histochemical, immunohistochemical, immunofluorescent and ultrastructural evaluation of a 56-year-old woman with superficial siderosis. Iron was concentrated in macrophages, superficial astrocytes and gray matter oligodendroglia deep within the cord. While spatially associated with dystrophic glial and neuronal spheroids, iron did not colocalize with mitochondria. Neurotoxic effects were observed despite selective iron localization only within a variety of non-neuronal cell types. [source]

Short-Term Antiandrogen Flutamide Treatment Causes Structural Alterations in Somatic Cells Associated with Premature Detachment of Spermatids in the Testis of Pubertal and Adult Guinea Pigs

REPRODUCTION IN DOMESTIC ANIMALS, Issue 3 2010
LR Maschio
Contents In spite of widespread application of flutamide in the endocrine therapies of young and adult patients, the side effects of this antiandrogen on spermatogenesis and germ-cell morphology remain unclear. This study evaluates the short-term androgen blockage effect induced by the administration of flutamide to the testes of pubertal (30-day old) and adult (65- and 135-day old) guinea pigs, with an emphasis on ultrastructural alterations of main cell types. The testes removed after 10 days of treatment with either a non-steroidal antiandrogen, flutamide (10 mg/kg of body weight) or a pharmacological vehicle alone were processed for histological, quantitative and ultrastructural analysis. In pubertal animals, flutamide androgenic blockage induces spermatogonial differentiation and accelerates testes maturation, causing degeneration and detachment of primary spermatocytes and round spermatids, which are subsequently found in great quantities in the epididymis caput. In post-pubertal and adult guinea pigs, in addition to causing germ-cell degeneration, especially in primary spermatocytes, and leading to the premature detachment of spherical spermatids, the antiandrogen treatment increased the relative volume of Leydig cells. In addition, ultrastructural evaluation indicated that irrespective of age antiandrogen treatment causes an increase in frequency of organelles involved with steroid hormone synthesis in the Leydig cells and a dramatic accumulation of myelin figures in their cytoplasm and, to a larger degree, in Sertoli cells. In conclusion, the transient exposition of the guinea pigs to flutamide, at all postnatal ages causes some degenerative lesions including severe premature detachment of spermatids and accumulation of myelin bodies in Leydig and Sertoli cells, compromising, at least temporarily, the spermatogenesis. [source]

Electron microscopic findings in non-alcoholic fatty liver disease: Is there a difference between hepatosteatosis and steatohepatitis?

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 3 2010
Emel Ahishali
Abstract Background and Aims:, Non-alcoholic fatty liver disease has long been accepted as benign; however, recent evidence suggests that the disease may progress to cirrhosis and hepatocellular carcinoma, although the natural course of the disease is still unclear. This study was designed to comparatively evaluate electron microscopic features of non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH). Methods:, Quantitative and semi-quantitative ultrastructural evaluations were performed on liver biopsies from 23 patients, 10 with NAFL and 13 with NASH. Results:, No statistically significant difference was noted between NAFL and NASH patients in ultrastructural features of hepatocytes including megamitochondria, intramitochondrial crystalline inclusions, mitochondrial matrix granules, foamy cytoplasmic appearance, electron-lucent and glycogen-containing nuclear regions, lipofuscin granules, or an increased frequency of vesicles containing electron-dense material in peribiliary Golgi zone; however, the mitochondrial diameter was significantly higher in the NASH patients. Intercellular distance and microvilli between hepatocytes, collagen and electron-dense material accumulation in the space of Disse, electron-dense material accumulation and microvillus density in bile canaliculi did not differ significantly between the groups. Conclusions:, Our data show that, although NAFL and NASH can be distinguished by their distinct light microscopic features, ultrastructural characteristics are similar, which suggests that NAFL may also have the potential to progress to fibrosis and cirrhosis like NASH. [source]