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Biomedical subjects

A Leone

Publications and source records attributed to A Leone.

At least 145 records · Page 8Linked to original sources
PubMed1981

One extra oligosaccharide chain of the high-mannose class in the E2 protein of a Sindbis virus isolate.

The number and nature of oligosaccharide chains in the E2 envelope protein (and its precursor PE2) from two strains of Sindbis virus, originally derived from the same HR strain, were investigated. The E2 glycoproteins (and the PE2 proteins) of the two strains had different electrophoretic mobilities on a sodium dodecyl sulfate-polyacrylamide gel. We observed that the glycopeptides from the E2 protein of one of the two strains included an extra oligosaccharide chain of the mannose-rich type. The altered pattern of glycosylation does not interfere with the intracellular migration of the protein and the envelopment and budding of the virus.

Glycopeptides↗
PubMed1980

Defective mutant of Sindbis virus with a smaller-molecular-weight form of the E1 glycoprotein.

We have isolated from a single plaque a mutant of Sindbis virus characterized by an E1 glycoprotein with higher electrophoretic mobility. This higher mobility is not attributable to a different extent of glycosylation of the protein nor to an altered proteolytic maturation pathway of the polypeptide precursor, but is the result of a deletion occurring during the replication of the viral RNA. The 26S RNA (the messenger for the Sindbis structural proteins) extracted from cells infected with the mutant is about 0.75 x 10(5) daltons smaller than the 26S RNA from the parental strain. As a consequence, in cells infected with the mutant, an E1 glycoprotein is synthesized with a polypeptide chain about 70 amino acids shorter. The biological relevance of this naturally occurring deletion of the viral genome is discussed.

Defective Viruses↗
PubMed1979

[Bone lesions in vibration induced disease: radiological study (author's transl)].

The authors examined 52 miners affected by Raynaud's phenomenon caused by vibrating instruments, mainly checking the involvement of the osteoarticular system. They found, in the articulation of the upper limbs, in addition to generic signs of arthrosis, zones of bone reabsorption (vacuoles), especially as regard the wrist and hands, and irregularities of the tufts. The authors consider these lesions as important feature of the technopathy.

Adult↗
PubMed1977

[Aortoplasty with dacron patch in the surgical treatment of aortic coarctation].

The indications for aortoplasty and the techniques employed are described. The advantages of using Dacron patches are explained, namely: restricted mobilisation of the aorta, no sacrifice of intercostal vessels, no risk of haemorrhage from ectasic collateral vessels with weak walls, or from the calcified aorta wall, and simplicity. The method requires lengthwise section (extended as necessary) of the aorta where it is restricted following the application of clamps, removal of the stenosing diaphragm and application of a lozenge-shaped patch, with continuous suture of the anterior edges of the opening in the vessel. It is pointed out that the method is especially indicated in cases with marked atheromatous alterations and in chil-childrens, whose aorta is thereby enabled to grow normally, since a sufficient part of the wall is left in its natural continuity.

Adolescent↗
PubMed1976

Formation of a Sindbis virus nonstructural protein and its relation of 42S mRNA function.

Chicken embryo fibroblasts infected with an RNA- temperature-sensitive mutant (ts24) of Sindbis virus accumulated a large-molecular-weight protein (p200) when cells were shifted from the permissive to nonpermissive temperature. Appearance of p200 was accompanied by a decrease in the synthesis of viral structural proteins, but [35S]methionine tryptic peptides from p200 were different from those derived from a 140,000-molecular-weight polypeptide that contains the amino acid sequences of viral structural proteins. Among three other RNA- ts mutants that were tested for p200 formation, only one (ts21) produced this protein. The accumulation of p200 in ts24- and ts21-infected cells could be correlated with a shift in the formation of 42S and 26S viral RNA that led to an increase in the relative amounts of 42S RNA. These data indicate that p200 is translated from the nonstructural genes of the virion 42S RNA and further suggest that this RNA does not function effectively in vivo as an mRNA for the Sindbis virus structural proteins.

Cell Line↗
PubMed1975

[Disadvantages of mechanical valve prostheses in the surgical treatment of mitral insufficiency].

Various disadvantages may be encountered with mechanical valve prostheses in the surgical management of mitral insufficiency; namely: 1) Early and secondary disinsertion; this is nearly always partial and is usually accompanied by haemolytic anaemial. 2) Infection with nil response to antibiotics. Death from septicaemia may be rapid. Replacement of the prosthesis is otherwise mandatory. 3) Thrombosis, usually partial, accompanied by one or more embolisms. Thrombo-embolism is more frequently noted in the first 6 months after implantation and becomes less common as time passes. 4) Deterioration of the movable part (ball variance) consisting of changes in colour and shape, with swelling and unevenness of the surface, breakage, pitting and loss of elasticity. 5) Low stroke volume syndrome. 6) Erosion of the septum and serious rhythm disturbances. 7) Proliferation of endothelial tissue leading to narrowing of the orifice. 8) Disturbed movement of the movable part, leading to intermittent or permanent blockage and loss of opening or closing play due to the interposition of fibrin and blood clots.

Anemia, Hemolytic↗