Search PubMed⌕ Search

Biomedical subjects

R Stanescu

Publications and source records attributed to R Stanescu.

68 records · Page 4Linked to original sources
PubMed1976

[Study by gel electrophoresis, of alpha chains and of CNBr peptides of collagen from epiphyseal cartilage in chondrodysplasia].

The alpha chains and the major CNBr - derived peptides of collagen of growth cartilage were studied in the following syndromes: thanatophoric dwarfism, pseudothanatophoric dwarfism, achondroplasia, pseudoachondroplasia, diastrophic dwarfism, metatropic dwarfism, Kniest disease, parastremmatic dwarfism, multiple exostoses, Blount disease and pycnodysostosis. After extraction of proteoglycans the collagen was solubilized by limited pepsin digestion purified, and the alpha chains were analysed by electrophoresis. The major CNBr - derived peptides were obtained by cleaving directly the cartilage after proteoglycan extraction. In some syndromes purified collagen was also cleaved. The CNBr peptides were analyzed by disc electrophoresis in SDS-polyacrylamide. Human normal growth cartilage and baboon cartilage were used as controls. The pattern of alpha chains and of major CNBr peptides was similar in all the cases studied, except one case of lethal diastrophic dwarfism in which the pattern of peptides showed the presence of type I collagen in quantities detectable by the present method. However in a milder case of diastrophic dwarfism the pattern of CNBr peptides was found normal. The present study does not exclude possible abnormalities of collagen at a higher lever of supramolecular organization in osteochondrodysplasias.

Adolescent↗
PubMed1976

Kniest syndrome.

Explore the source record for details and available documents.

Cartilage↗
PubMed1975

[Ultrastructural abnormalities of the chondrocytes in pycnodysostosis. Their relation to a disorder of lipid metabolism].

The ultrastructural study of the growth cartilage of pycnodysostosis reveals the presence of abnormal inclusions in the majority of the chondrocytes. The inclusions are single membrane bound and contain granular material and lamellar irregularly interwoven structures which at very high magnification appear to be made up of dense parallel bands. These vacuoles displace adjacent structures and some of them appear to be closely related to the Golgi apparatus. In addition, appearances are sometimes seen which suggest the expulsion of the vacuoles into the cell capsules. The abnormal chondrocyte inclusions are visible by optic microscopy and stained with Nile blue on frozen section. Thus, histochemical and ultrastructural characteristics suggest a lipid (probably phospholipid) content. Many authors have already stressed the role of lipids in the process of calcification. The abnormalities described might bear some relation to the densification of the skeleton seen in pycnodysostosis.

Cartilage↗
PubMed1975

[Poly-epiphyseal dysplasia, probably autosomal recessive. Contribution of the ultrastructural study to the discovery of this autonomous form].

An ultrastructural study of growth cartilage permitted individualization of a particular form of polyepiphyseal dysplasia which differs clinically and radiologically only slightly from the dominant form. The main difference concerns the superior femoral epiphyses which are more flattened and spread out. Inclusions, probably of lysosomial origin and containing granulous or filamentous material, were observed. This aspect is different from that observed in the dominant form and consisting of swellings of the endoplasmic reticulum with a suggestion of a periodical structure. The mode of inheritance could not be firmly demonstrated. Some degree of consanguinity of the second patient's parents favours an autosomal recessive inheritance.

Cartilage↗
PubMed1975

Ultrastructural abnormalities of the chondrocytes of the growth cartilage of a type of poly-epiphyseal dysplasia with a probable autosomal recessive transmission.

In two cases of polyepiphyseal dysplasia with a probable autosomal recessive transmission, ultrastructural abnormalities were found in the chondrocytes of the tibial epiphyseal growth plate. The largest part of the chondrocytes is occupied by many large vacuoles. They are bounded by a single membrane and have an electron-lucent background in which electron-opaque granules and delicate spiral filaments are visible. The ultrastructural abnormalities suggest a storage disorder probably limited to the chondrocytes.

Epiphyses↗
PubMed1975

Age-dependent change in the gel-electrophoretic pattern of proteoglycans of human growth cartilage.

The gel-electrophoretic pattern of dissociated proteoglycans was studied in 7 fetuses, 5 premature newborns, 4 term newborns, 5 infants and 5 children. The tibial growth cartilage was extracted with 4 M guanidinium chloride. After dialysis against 8 M urea at pH 7 the proteoglycans were obtained by ion chromatography in urea on DEAE cellulose and submitted to gel electrophoresis on polyacrylamide agarose gels. Gel electrophoresis of proteoglycans showed a different pattern in fetuses from that found in children. The change occurs in the first months of extrauterine life.

Adolescent↗
PubMedDate not supplied

Fragilitas ossium: a new autosomal recessive mutation in the mouse.

Fragilitas ossium, fro, is an often lethal recessive mutation that was discovered in a randombred stock of mice after treatment with the chemical mutagen tris(1-aziridinyl) phosphine-sulphine. The fro/fro mice have osteoporosis-bending and fracture of the long bones-that is associated with apparently normal cartilage growth. The roentgenological and pathological features are similar to those of the severe, often lethal recessive form of human osteogenesis imperfecta.

Animals↗
PubMedDate not supplied

The lethal chondrodysplasias.

The lethal chondrodysplasias are a complex group of diseases of which little is known. Three disorders have been well characterized; achondrogenesis, thanatophoric dwarfism, and the lethal chondrodysplasias with polydactyly. Pathological studies of epiphyseal cartilage confirm the separateness of these diseases but further work is necessary to specify the limits of variations. In achondrogenesis, relatively minor forms differ greatly from the usual description. In the chondrodysplasias with polydactyly, skeletal involvement appears to vary from one case to another. Furthermore, we must pursue the genetic studies in thanatophoric dwarfism where the exact mode of inheritance is known.

Bone and Bones↗