Search PubMed⌕ Search

Biomedical subjects

A Zanella

Publications and source records attributed to A Zanella.

At least 91 records · Page 5Linked to original sources
PubMed1987

A study of several red cell enzyme markers in two samples of the Italian population. Report of new CA1 and PGD variant phenotypes.

Gene frequencies for 17 red cell enzymatic markers have been determined in two samples of the Italian population (Lombardy and Tuscany regions). A significant difference was found between the two samples for the AK1 and PGM1 systems (AK1*2 .028 and .044, PGM1*2 .254 and .301 in Lombardy and Tuscany respectively). Variant phenotypes, for PEPA, PEPB, CA2, PGM2, PGD and GPT markers, have been observed; some of these are due to new alleles occurring at the CA2 and PGD loci.

Alleles↗
PubMed1985

Triosephosphate isomerase deficiency: 2 new cases.

2 new cases of triosephosphate isomerase (TPI) deficiency associated with severe haemolytic anaemia in 2 unrelated Italian families are described. Only 1 case was extensively investigated. TPI deficiency was detectable in erythrocytes, leucocytes, platelets and plasma. The mutant enzyme showed normal Km for GAP and increased Km for DHAP, with an higher than normal equilibrium constant, decreased thermostability, and abnormal electrophoretic pattern due to the lack of the fastest moving component. The immunological characterization revealed a lower than normal inactivation by specific antiserum, while the double immunodiffusion pattern and the precipitin curve were normal. Lymphocyte, granulocyte and platelet functions were impaired.

Blood Platelets↗
PubMed1985

Autoimmune hemolytic anemia in a cadaveric renal transplant recipient treated with cyclosporine.

A case of autoimmune anti-c hemolytic anemia was observed in a cadaveric renal transplant recipient treated by cyclosporine. Severe anemia had been preceded by an episode of cholangitis followed within a few days by a viral infection. Anemia improved after three plasmaphereses and after cyclosporine therapy was substituted by azathioprine and steroid doses were increased. It is hypothesized that cyclosporine withdrawal may have favored the improvement of hemolysis by favoring the suppression of antibody-producing cells.

Adult↗
PubMed1985

Lipoprotein metabolism in patients with elevated lipoprotein-lipase activity in adipose tissue.

We have evaluated the relationships between adipose tissue lipoprotein-lipase activity (AT-LPL) or post-heparin plasma lipolytic activity (PHLA) and the composition of circulating lipoproteins in 7 patients with multiple symmetric lipomatosis (MSL). In addition we have investigated the behaviour of serum triglycerides after an oral fat load (1 g triglycerides/kg body weight) in 5 MSL patients and in 5 age and sex matched controls. We found significantly higher values of HDL, HDL2 and HDL3 cholesterol in MSL patients than in controls. Moreover, HDL2/HDL3 cholesterol ratio was higher in MSL patients than in controls, which indicate a predominant increase in HDL2 subfraction. The mean values of AT-LPL in lipomatous tissue was significantly higher than in control tissue. A positive statistically significant correlation was found between AT-LPL activity and HDL, HDL2 and HDL3 cholesterol values. After the fat load the maximal increments of serum triglyceride levels and the triglyceride areas over 8 and 12 h are lower in MSL patients than in controls; there was an inverse, statistically significant correlation between the total PHLA or the extrahepatic PHLA values and the triglyceride areas after lipid load. We conclude that MSL represents a useful naturally occurring model for the study of the role of AT-LPL in the metabolism of triglyceride-rich lipoproteins and in the clearance of lipoproteins in the post-prandial phase.

Adipose Tissue↗
PubMed1984

Functional properties of the whole blood in a carrier of Hb-Atlanta: beta 75 (E-19) Leu-Pro.

The Authors illustrate the main functional parameters of the whole blood in a heterozygous carrier of the unstable Hb-Atlanta. The most important results are represented by a right-shifted P50, by a lowered value of n and by an almost normal pH-depending Bohr effect. It is very likely that the first report depends on the relative Hb-A deficiency, whereas the second one could be due to the presence of the unstable Hb. Moreover, the linkage between this latter and DPG would be present.

Blood Physiological Phenomena↗
PubMed1984

A new test for the laboratory diagnosis of spherocytosis.

A new test for the laboratory diagnosis of spherocytosis, conventionally called 'Pink test', is presented. This test, semi-quantitatively or quantitatively, determines the hemolysis of small blood samples in a solution containing glycerol (135 mmol/l), NaCl (25 mmol/l), NaN3 (1.5 mmol/l), buffered to pH 6.66 with Bis-Tris (70 mmol/l) and HCl. 'Pink test', as well as 'acidified' glycerol lysis test, were positive in 100% of 42 patients suffering from hereditary spherocytosis, and optimally discriminated them from healthy subjects, showing a diagnostic sensitivity greater than 'standard' glycerol lysis test and osmotic fragility in hypotonic saline solutions of fresh or incubated blood. 'Pink test' was also positive in some cases of renal failure, immunohemolytic anemia, chronic hemoproliferative disorders, normal pregnant women, and negative in other microcytic anemias (beta-thalassemia, iron deficiency anemia). The results do not critically depend on pH of the solution (differently from those obtained with 'acidified' glycerol lysis test), and for this reason they show a good reproducibility.

Buffers↗
PubMed1983

Diagnostic value of the glycerol lysis test.

The diagnostic value of the standard glycerol lysis test (GLT) has been evaluated by studying 95 cases of hereditary spherocytosis (HS), 513 beta- and 25 alpha-thalassemia trait (Th) carriers, 170 iron-deficient patients (ID), and 217 patients with miscellaneous hematological conditions. The sensitivity of the test, at 95% specificity, was 97% for beta-Th, 53% for ID, and only 36% for HS, so that the predictive value of a positive result is practically nil for HS, 50% to 85% for Th, and 10% to 35% for ID, depending on the prevalence ratio of the disease in the examined population. The technical variability of GLT, explored by a proper experimental design, was found to be rather high, its main components being repeatability and variability of reagent preparations. The dependence of the results on operators was negligible. It is concluded that GLT is not suitable as a laboratory test for the detection of abnormalities in red cell osmotic fragility because of its very low sensitivity toward increased fragility. For decreased red cell osmotic fragility, the sensitivity of GLT is high; however, it is less valuable than the traditional 0.35% NaCl method as mass screening test for the detection of beta-Th, giving more false positive results.

Analysis of Variance↗
PubMed1982

Marek's disease--survey on vaccination failures.

Twelve years after the initial development of efficacious vaccines against Marek's disease--prepared mostly from HVT--and their subsequent use on a large scale, there is a general opinions that failures have been increasing in incidence and in severity. Many factors have been held responsible for these failures, and, though efforts are being made to obviate them, no acceptable solutions have been found sofar in the control of the disease in the field. If mistakes in the preparation, storage handling and administration of vaccine are excepted, because these mistakes, though not infrequent, are easier to prevent, the main causes that must be considered are: 1. The heavy and very early exposure to infection, in houses that are not well disinfected or when birds are reared for many cycles in the same place without cleaning or disinfecting, or in multi-age farms, where habits become established, particularly in broilers and pullet rearing, and also for economic reasons. 2. The considerable variability in the susceptibility to MD of different genetic strains of commercial chickens. 3. The appearance of the supposed new biological variants of virus, as recently found in the U.S. The purpose of this study has been the evaluation of the influence of these causes on the more and more frequent outbreaks of MD in our country. While the importance of the genetics and of the degree of and age at exposure has been irrefutably proven, data concerning the appearance of biological variants of MD virus are still short and controversial.

Animals↗
PubMed1981

A modified 'low pH' lignocaine method to isolate human monocytes: a comparison with other separation procedures.

A modified 'low pH' lignocaine method for the recovery of human monocytes from untreated plastics is described and compared with other adherence separation procedures, viz. mechanical scraping by a rubber policeman, microexudate-coated plastic method and pretreatment of plastics by the fetal calf serum (FCS). Monocytes separated by each of the above-mentioned techniques carried out in parallel were characterised by morphological and functional criteria: non-specific esterase staining, contamination by T- and B-lymphocytes, viability, adherence, neutral red uptake, phagocytosis of yeast particles, random mobility, chemotaxis, and tumoricidal activity both in the absence and in the presence of interferon and lymphokines. The 'low pH' lignocaine method appears to be a simple and reproducible technique for the isolation of human monocytes. It seem preferable to other adherence procedures inasmuch as it yields viable, pure and functionally intact monocytes without requiring preconditioned plastics.

Blood↗
PubMed1981

Functional study of lipids of PNH red cell membranes: susceptibility of liposomes to reactive lysis.

Lipids extracted with chloroform-methanol from red blood cell membranes of 7 PNH and 13 control subjects were used for the preparation of liposomes, which were then examined with the reactive lysis test. PNH liposomes lysed to a higher extent than control liposomes as indicated by the higher dilution of the limiting complement reagent that was necessary to lyse 50% of the PNH liposomes. A similar finding was also observed with liposomes made of lipids from AET-treated red cells. The enhanced reactive lysis can be attributed to the polar lipid fraction, as indicated by the increased lysis of hybrid liposomes prepared from this polar lipids extracted from PNH erythrocyte membrane and lipids extracted from normal erythrocyte membrane. The increased susceptibility to reactive lysis does not seem to be specific of PNH liposomes, since it was also observed with liposomes prepared from lipids of red cells from beta-thalassemia major and autoimmune hemolytic disease.

Adult↗
PubMed1980

The first stable variant of erythrocyte glucose-phosphate isomerase associated with severe hemolytic anemia.

A new variant of glucosephosphate isomerase (GPI) associated with hemolytic anemia, mental retardation, and muscular hypotonia is described. The defective enzyme showed increased affinity for fructose-6-phosphate (F-6-P), decreased affinity for glucose-6-phosphate (G-6-P) altered electrophoretic and isoelectrofocusing patterns, and shift to the left of the precipitin curve. The enzyme was stable under all the conditions tested (heat, urea, guanidine-HCl, and storage). Optimum pH, Ki for 6-phosphogluconic acid (6-PGA) and for erythrose-4-phosphate (E-4-P), molecular weight, GPI-related antigen concentration, immunodiffusion pattern, and immunoinactivation were in the normal range. This is the first example of the association of a stable mutant GPI with severe hemolytic anemia. Enzyme instability has been present in all previously reported cases.

Anemia, Hemolytic, Congenital↗
PubMed1980

Metabolic impairment and membrane abnormality in red cells from Huntington's disease.

The following aspects have been investigated in 10 patients affected by Huntington's disease )HD): --extensive haematological investigations; --red cell enzyme activities and level of the most important glycolytic intermediate compounds; --protein, lipid and carbohydrate composition of the erythrocyte membrane and membrane polarity; --effects of in vitro aging on red cell membranes. Lack of 4.5 protein band in SDS-PAGE and 14-fold decrease in membrane-bound catalase were found in the in vitro aged red cells from the 10 HD patients examined. Na+ + K+ATPase was slightly higher than normal in all the patients. Red cells from 5 out of 8 patients showed a decrease in reduced glutathione and phosphoenolpyruvate levels and/or an increase in hexokinase, glucose-6-phosphate dehydrogenase, pyruvate kinase and glutathione reductase activities. The haematological investigations, the protein lipid and carbohydrate composition of the fresh red cells, the membrane polypeptide aggregates and the membrane polarity evaluated by microspectrofluorometric analysis were normal.

Acetylcholinesterase↗
PubMed1980

Acidified glycerol lysis test: a screening test for spherocytosis.

Acidified glycerol lysis test (AGLT) is a screening procedure which has been developed for spherocytosis. AGLT was found positive in 100% of 48 patients suffering from hereditary spherocytosis, 100% of nine couples of affected parents, and 86% of 14 couples of clinically healthy parents. The test was positive in acquired spherocytosis and negative in normal controls. AGLT appears to have a predictive value higher than the entire battery of conventional tests. It is simple, rapid, inexpensive, gives clear-cut results and requires minute amounts of blood. It can be performed on blood stored for up to 24 h.

Adult↗