Search results for "Ultrastructure"
showing 10 items of 224 documents
Collagen ultrastructure in ruptured cruciate ligaments
1992
The ultrastructure of collagen fibrils was investigated in normal (n 39) and ruptured (n 23) human anterior cruciate ligaments. The normal ligament had a complex three-dimensional structure. Collagen fibrils predominantly had a unidirectional course with parallel arrangement and a mean diameter of 75 (20-185) nm. Four days after anterior cruciate ligament rupture, the mean fibril diameter was increased; it later decreased, probably due to synthesis of young, thin 30-40 nm fibrils. Interfibrillar dysplastic collagen fibrils were detected in the extracellular matrix of ruptured ligaments. They were more frequently found later than 3 days after rupture and were seen also at a distance of 2-3 c…
Cellular ultrastructure of the ruptured anterior cruciate ligament. A transmission electron microscopic and immunohistochemical study in 55 cases.
1994
To evaluate the cellular ultrastructure following injury, we examined the anterior cruciate ligaments in 55 patients with complete tears in different phases after the injury and compared them to a control group of 39 cadaver knees. Samples were analyzed by electron microscopy, immunofluorescence, and ultramorphometry. After an invasion of inflammatory cells into the stumps of the ruptured ligaments, a marked proliferation of fibroblasts was found at the end of Phase 1 (2-3 days after the ligament injury), that was even more pronounced at the beginning of Phase II (4-17 days). These cells were initially highly metabolically active and secreted Type III collagen precursors. In Phase III (4-45…
Ultrastructural patterns of primary ciliar dyskinesia syndrome.
2005
Clinical presentation, ciliary ultrastructure, and nasal mucociliary transport by a radioisotopic technique were analyzed in 14 Kartagener syndrome patients. In this study the most common pattern was the absence of outer and inner dynein arms in 57% of cases. Also reported are 14% patients with short inner dynein arms. A total of 29% of the patients showed normal dynein arms. Mucociliary stasis was observed in 13 cases. Primary ciliary dyskinesia syndrome and Kartagener syndrome are clinically homogeneous and morphologically heterogeneous. The authors conclude that a typical clinical presentation with an altered mucociliary transport obtained by radioisotopic technique is diagnostic althoug…
Diffuse Type of Giant-Cell Tumor of Tendon Sheath: An Ultrastructural Study of Two Cases With Cytogenetic Support
2002
Two cases of the diffuse type of giant-cell tumor of the tendon sheath (GCTTS) are described. Both tumors arose in the vicinity of large joints of the lower extremity, showing similar clinical and radiological features. Histologically, a proliferation of polygonal mononuclear cells was seen, together with osteoclastlike giant cells, foam cells, and siderophages. The tumors were poorly delineated, displaying an infiltrative pattern into the neighboring soft tissues. Immunohistochemically, strong expression of vimentin, neuron-specific enolase, A1-antitrypsin, and CD68 was found in both mono- and multinucleated tumor cells. At the ultrastructural level, mononuclear cells revealed a diverse mo…
Clinicopathological and ultrastructural characterization of periapical actinomycosis
2019
Background The aim of the present study was to analyze the clinicopathological and the ultrastructural features of periapical actinomycosis (PA) cases. Material and Methods Data from the files of an oral pathology laboratory were retrieved and the findings of histopathological analysis were evaluated. Hematoxylin–eosin (HE), a modified Brown & Brenn, and Grocott stains as well as ultrastructural analysis using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were utilized. Results Six cases were obtained, 4 females and 2 males, with a mean age of 34 year-old. Two cases were symptomatic, lower teeth and the anterior region were more commonly affected, and all…
Long-term storage in liquid nitrogen does not affect cell viability in cardiac valve allografts
2007
Liquid nitrogen is the most common medium used by tissue banks for the storage of cryopreserved heart valves. This study evaluates the effect of the length of storage on human cryopreserved heart valves. Human tissues (14 aortic and 13 pulmonary) were frozen in a controlled-rate freezer (1 degrees C/min) and stored in the liquid phase of a nitrogen tank for 9.1+/-1.6 years. The preservative solution was medium M199 containing 5% human serum albumin and 10% Me(2)SO. After thawing in a water bath at 42 degrees C, the cryoprotectant was removed. Then, fragments from vascular wall and leaflet were dissected. Explant cultures and histological studies were performed in order to assess cell viabil…
Studies on the subcellular pathophysiology of sublethal chronic cell injury.
1974
Summary This paper summarizes some of the important subcellular events occurring after chronic sublethal cell injury. Chronic cell injury is defined as the result of injurious stimuli which permit cell survival though in altered steady states for protracted periods of time. The importance of ultrastructural and biochemical studies of these phenomena is emphasized. Among the phenomena discussed are alterations in lysosomes, cellular hypertrophy, fatty metamorphosis, alterations in microfilaments and microtubules, alterations in mechanisms of transcription and replication, disturbances in the cell surface and transport across the cell membrane, and alterations in intracellular transport.
Revised nomenclature and classification of inherited ichthyoses: Results of the First Ichthyosis Consensus Conference in Soreze 2009
2010
Background: Inherited ichthyoses belong to a large, clinically and etiologically heterogeneous group of mendelian disorders of cornification; typically involving the entire integument. Over the recent years, much progress has been made defining their molecular causes. However, there is no internationally accepted classification and terminology. Objective: We sought to establish a consensus for the nomenclature and classification of inherited ichthyoses. Methods: The classification project started at the First World Conference on Ichthyosis in 2007. A large international network of expert clinicians, skin pathologists, and geneticists entertained an interactive dialogue over 2 years, eventua…
A case of lipogranulomatosis Farber: some clinical and ultrastructural aspects
1985
A 20-month-old girl showed typical clinical signs of Farber disease: hoarseness since birth, and periarticular subcutaneous painful nodules. Complete deficiency of acid ceramidase activity was found in cultured skin fibroblasts. An electron microscopic examination of a dermal nodule disclosed pathognomonic tubular inclusions in histiocytes. In epidermal cells zebra-body-like and needle-like lysosomal inclusions were found. Their ultrastructure is different from that of the intrahistiocytic lysosomal inclusions. Probably three clinical types of Farber disease may be distinguished according to the symptomatology and the course of the disease: a severe type, an intermediate type and a relative…
Ultrastructure of the Retina in Adult Neuronal Ceroid Lipofuscinosis
1998
A 33-year-old woman died of biopsy-proven adult neuronal ceroid lipofuscinosis (NCL) or Kufs’ disease marked by fingerprint and curvilinear lipopigments in neural and nonneural cell types. She had never experienced visual impairment or shown electroretinographic abnormalities. At autopsy, her retina appeared intact without degeneration at the light-microscopic level, but nerve cells in different layers were loaded with lipopigments of the granular type. This appears to be the third ultrastructural study of the retina in a patient with adult NCL, a former one showing preservation of the retina, another retinal degeneration. Thus, only further molecular genetic data will clarify the nosology …