PubMed Health⌕ Search

Biomedical subjects

A Scanu

Publications and source records attributed to A Scanu.

At least 19 recordsLinked to original sources
PubMed1996

[Lipoprotein(a) as an athero-thrombotic risk factor: epidemiologic evidence and possible pathogenetic mechanisms].

Lipoprotein (a) [Lp(a)] has been known for more than 20 years as a peculiar "variant" of low-density lipoproteins (LDL), the recent interest for which mostly derives from its epidemiological and maybe pathogenetic link with coronary artery disease and atherosclerosis. The protein moiety of Lp(a)-apo(a)-is a glycoprotein produced by the liver, with evident structural analogies with plasminogen. A large variety of apo(a) isoforms have been described, with large variability in molecular weight, encoded by alleles located on chromosome 6. Plasma concentrations of Lp(a) are largely genetically determined, but variations on these levels are induced by changes in hepatic synthesis due to changes in control factors (for example in proteinuric syndromes). Many-but not univocal-epidemiological pieces of evidence indicate that high plasma concentrations of Lp(a) are associated with atherosclerosis and its cardiac, cerebral and peripheral manifestations, thereby potentially identifying a new cardiovascular risk factor, independent from plasma concentrations of LDL. This review will discuss such evidence and the mechanisms potentially linking Lp(a) and atherosclerosis. Proposed mechanisms include, among others, the susceptibility of Lp(a) to oxidation, the interference with mechanisms of fibrinolysis and the induction of endothelial activation.

Arteriosclerosis↗
PubMed1994

[Treatment of early colorectal carcinoma: surgery or endoscopy?].

This retrospective study analyses the value of endoscopic polypectomy as the operation of choice in cases of early invasive colorectal carcinoma located on the adenomatous polyp. Under these conditions the authors outline their therapeutic strategy, based not only on the histological characteristics of lesions, but also on the evaluation of the risk/benefit ratio established in relation to the characteristics of each individual patient.

Adenomatous Polyps↗
PubMed1994

[Chronic pancreatitis: notes on diagnosis and surgical therapy].

The authors analyse their experience of 30 cases of which 25 underwent surgery. In addition to the onset of complications, indications for surgery were based on the presence of severe painful symptoms which did not respond to medical treatment. Over the past few years the latter have represented one of the main indications with a success rate of between 80-90% of cases. The type of surgery must be personalized to the characteristics of each individual patient on the basis of morphological alterations of the gland, which are easily defined during a preoperative study using CPRE, ultrasonography and CT. Of these, CPRE has been found to be the most reliable in diagnostic terms, since it can detect structural alterations at a relatively early phase and is of considerable value in differential diagnosis, which is at times extremely difficult, with pancreatic carcinoma.

Aged↗
PubMed1968

Properties of human serum low density lipoproteins after modification by succinic anhydride.

Human serum low density lipoprotein of d 1.019-1.063 (LDL(2)) treated with succinic anhydride at pH 7.5-8.0 showed the same chemical composition, hydrodynamic properties (flotation and sedimentation coefficients, intrinsic viscosity) and optical properties (circular dichroism) as untreated LDL(2). However, in contrast to LDL(2), the succinylated product (s-LDL(2)) failed to react with rabbit anti-LDL(2) antisera. Extraction with ethanol-ether 3:1 yielded the succinylated apoprotein (s-apo-LDL(2)), which was, unlike untreated apoprotein, soluble in aqueous buffers. Succinylated apoprotein, which was also immunologically unreactive, appeared to differ in structure from s-LDL(2), as assessed by the parameters of intrinsic viscosity and circular dichroism. The molecular weights of both LDL(2) and s-LDL(2) obtained by the technique of sedimentation equilibrium were 2.1-2.3 x 10(6). By the same method, s-apo-LDL(2) gave an uncorrected figure of 3.95-4.15 x 10(4) and, after correction for succinyl functions, of 3.60-3.80 x 10(4). Because of the assumptions made in the computations, the latter figure was considered approximate. The marked differences in molecular weight between s-apo-LDL(2) and whole apo-LDL(2) ( approximately 5 x 10(5)) were taken to support the subunit structure of apo-LDL(2), which is envisaged as an aggregate of about 12 subunits which dissociate upon succinylation. Further, the large percentage (about 90%) of the free amino groups of LDL(2) found to react with succinic anhydride suggests that these groups are at the surface of the molecule.

Amino Acids↗
PubMed1966

Serum high-density lipoprotein: effect of change in structure on activity of chicken adipose tissue lipase.

The high-density (1.063 to 1.21 g/ml) lipoprotein in human serum was analyzed as activator for a lipoprotein lipase isolated from chicken adipose tissue. The activating capacity was lost when the lipoprotein was extracted with a mixture of ethanol and ethyl ether (3:2 by volume) at -10 degrees C and it was restored upon incubation of the extracted protein with aqueous sols of either whole phospholipids or the lecithin fraction prepared from the high-density lipoprotein. Since phospholipid sols alone proved ineffective as substrate activators, the complex which forms upon incubation of the extracted lipoprotein with phospholipids appears to be a necessary requirement for lipoprotein lipase activity.

Adipose Tissue↗