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Biomedical subjects

E Arosio

Publications and source records attributed to E Arosio.

At least 73 records · Page 4Linked to original sources
PubMed1989

Platelet intracellular free Ca2+ after incubation with plasma from hypertensive patients.

Variations in intracellular free calcium were measured in platelets from normal donors, incubated with plasma from hypertensive patients and from control subjects to test the hypothesis that a circulating factor might induce an increase in calcium concentration. Before incubation, plasma was heat-inactivated or ultrafiltered. Incubation both with heat-inactivated and ultrafiltered plasma failed to result in any significant modifications in intracellular free calcium. Similarly, no significant increase was observed after incubation with ouabain at concentrations ranging from 10(-7) to 10(-4) M. No significant differences were observed between platelets incubated with plasma from hypertensive as compared with control subjects. These findings are not consistent with the hypothesis that the increase in intracellular free calcium observed in platelets of hypertensive patients may be due to a plasma ouabain-like factor.

Adult↗
PubMed1988

Intracellular free Ca2+ in platelets of essential hypertensive patients. Lack of correlation with clinical and laboratory data.

Platelet intracellular free Ca2+, [Ca2+]i, was found to be higher in 64 hypertensive patients than in 65 age- and sex-matched normotensive controls (142.7 +/- 3.8 nmol/l vs 126.6 +/- 2.4 nmol/l, M +/- SEM, respectively; P less than 0.001). No differences were observed in hypertensive patients in relation to age, duration of hypertension or severity of retinopathy, but a slight correlation was observed (r = 0.275, P less than 0.05) between platelet [Ca2+]i and systolic blood pressure. No correlations were found between platelet [Ca2+]i and plasma cholesterol, triglycerides, aldosterone or renin activity. These data appear to support the hypothesis that increased platelet [Ca2+]i in hypertensive patients is more likely to be related to a primary cellular abnormality than to activation by extrinsic humoral or vascular factors.

Adolescent↗
PubMed1987

Increased basal and thrombin-induced free calcium in platelets of essential hypertensive patients.

Intracellular free calcium, [Ca2+]i, was studied in platelets of essential hypertensive subjects and normotensive controls under basal conditions and after stimulation with epinephrine, norepinephrine, angiotensin II, ouabain, and thrombin, using the fluorescent calcium indicator quin 2. Basal [Ca2+]i was significantly higher in hypertensive subjects (n = 32) than in normotensive controls (n = 30; 167.4 +/- 5.0 vs 143.2 +/- 3.1 nmol/L; p less than 0.001). Epinephrine, norepinephrine, angiotensin II, and ouabain had no effect on platelet calcium, whereas thrombin induced a dose-dependent increase in [Ca2+]i in both the presence and absence of extracellular calcium. This [Ca2+]i increase in the presence of extracellular calcium, which depends mainly on calcium influx, was significantly higher (p less than 0.05) in platelets of hypertensive subjects at all thrombin concentrations (ranging from 0.025-0.1 U/ml), while the [Ca2+]i increase in the absence of extracellular calcium, which depends only on release from intracellular stores, was similar in hypertensive subjects and controls. These results suggest that, in essential hypertension, there is not only increased platelet resting [Ca2+]i but also an increase in agonist-mediated calcium influx, which appears to indicate a cell membrane abnormality in the platelets of subjects with essential hypertension.

Adult↗
PubMed1987

Antihypertensive activity of enalapril. Effect of ibuprofen and different salt intakes.

It has been suggested that angiotensin-converting enzyme (ACE) inhibitors may also act through the renal prostaglandin (PG) system; moreover, it has been shown that nonsteroidal antiinflammatory drugs (NSAIDs) are capable of reducing the antihypertensive activity of ACE inhibitors. Sixteen essential hypertensive patients (WHO stages, I-II, eight on a low-sodium diet and eight on a high-sodium diet) were treated with enalapril, 20 mg/day per os, for 4 days. On days 3 and 4, ibuprofen, 1,200 mg/day per os, was also given. Enalapril reduced blood pressure, particularly in the group on the low-sodium diet. Urinary 6-keto-PGF1 alpha, an indicator of renal PGI2 production (determined by HPLC-RIA), increased in the first few hours after enalapril in the low-sodium group. Ibuprofen did not reduce the antihypertensive effect of enalapril, nor did it affect plasma renin activity or plasma aldosterone. Only a slight reduction in 6-keto-PGF1 alpha excretion was observed after enalapril plus ibuprofen. It is suggested that the effect of enalapril on urinary 6-keto-PGF1 alpha excretion is largely dependent on factors such as sodium intake.

6-Ketoprostaglandin F1 alpha↗
PubMed1986

Penetration of ceftriaxone into human pleural fluid.

The pharmacokinetics of ceftriaxone were studied for seven patients with pleural effusion of various etiologies. All patients received 1 g of antibiotic, administered as an intravenous bolus. The pleural fluid had a high total protein content (6.0 g/dl). Ceftriaxone levels in plasma and in pleural fluid were determined by the agar well diffusion technique. Total and free drug concentrations in pleural fluid reached 7 to 8.7 and 3.8 to 2.3 micrograms/ml, respectively, in 4 to 6 h. The disappearance of the drug from the pleural fluid was very slow. In these patients, therapeutic ceftriaxone levels were present for at least 53 h in pleural fluid.

Adult↗
PubMed1986

Ceftazidime in patients with severe Pseudomonas infections.

Forty patients suffering from severe Pseudomonas infections (13 urinary tract infections, 8 of which complicated, 16 cases of pneumonia, 3 cases of sepsis, 1 case of sepsis with osteomyelitis, 2 cases of osteomyelitis, 1 case of ophthalmitis, and 4 cases of peritonitis) were treated with ceftazidime (1-6 g/die). Most cases presented with severe underlying conditions associated with, or predisposing to, infection (surgical intervention, neoplasia, immunodepression, etc.). Both microbiological results (38 out of 43 strains eradicated) and clinical outcome (28 infections cured, 10 improved, and only 2 unchanged) proved highly satisfactory. The authors advocate the empirical use of ceftazidime as first-line single-drug therapy in severe hospital acquired infections in high-risk patients.

Adolescent↗
PubMed1986

Ketoconazole: clinical evaluation in severe fungal infections.

Ketoconazole, a new imidazole-derivative antifungal agent, has been studied in sixteen patients with systemic fungal infections. Seven patients had deep localized infections (three cases with pneumonia and one case each with urinary infection, osteomyelitis, endophthalmitis and peritonitis); three patients suffered from granulomatous or acute mucocutaneous infections and six patients had fungal septicemia. All patients suffered from severe underlying diseases and/or predisposing factors such as antibiotic treatment, immunosuppressive therapy or indwelling catheters. Candida albicans was isolated in 13 cases, C. parapsilosis (septicemia), Aspergillus (ophthalmitis) and Mucor (pneumonia) in the other three cases. Ketoconazole was administered orally at daily dosages of 400-800 mg; 5-fluorocytosine was associated in four cases. Out of the ten patients with localized infections, seven were cured and three improved. Two of the six septic patients were cured, one improved who subsequently died from Pseudomonas septic shock and three patients showed no improvement. Two relapses were recorded, both followed by further eradication. The tolerance of the drug was always excellent. Ketoconazole proved a very effective and well-tolerated drug in systemic infections, caused by opportunistic fungi in high-risk patients.

Adolescent↗
PubMed1985

In situ identification of immune competent cells in gastrointestinal mucosa: an evaluation by immunoelectronmicroscopy.

The in situ identification of lymphocyte subpopulations by means of immunopathological techniques using specific monoclonal antibodies provides a tool for the study of the gastrointestinal-associated lymphoid tissue (GALT) in health and disease. In this field, monoclonal antibodies have been applied previously using light microscopy and either immunofluorescence or immunoperoxidase; however, these techniques are not sensitive enough to allow precise evaluation of localization of labelling. We describe an immunoelectronmicroscopic method, which defines labelling specificity, since it allows the identification of cells by immunophenotype labelling and ultrastructural markers simultaneously. This in turn allows a better evaluation of the labelled cells and of the relationship between labelled and unlabelled cells. The main features of the method are the use of fresh tissue samples, fixing in paraformaldehyde CaCl2, and the coupling of the immune reaction to an amplification system (avidin-biotin-peroxidase complex). The technique yields a good preservation of cellular ultrastructure, together with a strong and specific immunolabelling. Our results confirm the high specificity of monoclonal antibodies when applied to immunopathology techniques. We confirm the pattern of distribution of various lymphocyte subsets in the jejunal mucosa described by other authors by light microscopy.

Antibodies, Monoclonal↗
PubMed1984

Increased leukocyte aggregation in patients with hypercholesterolaemia.

Leukocyte aggregation induced by N-formylmethionyl-leucyl-phenylalanine (FMLP) has been measured in a group of patients with hypercholesterolaemia (n = 22) and in a group of control subjects (n = 26), age- and sex-matched. When hypercholesterolaemic patients were divided into two groups, with a discriminatory level of 7.7 mmol/l of plasma cholesterol, FMLP-induced leukocyte aggregation of patients with greater than 7.7 mmol/l of plasma cholesterol was significantly higher compared both with control subjects and patients with plasma cholesterol levels less than 7.7 mmol/l. A positive significant correlation was found between leukocyte aggregation and plasma cholesterol, whereas no correlation was observed between leukocyte aggregation and plasma triglycerides or APO-B levels. These findings provide further support for the hypothesis that elevated plasma cholesterol levels may induce a cellular membrane abnormality responsible for the increased leukocyte aggregation and, subsequently, endothelial damage.

Adolescent↗
PubMed1984

Pseudomonas septicaemia. A review of 60 cases observed in a university hospital.

Epidemiological, clinical features and the pathogenesis of 60 cases of pseudomonas septicaemia, observed over a period of 7 years from 1975 to 1981, are described. The mean frequency of occurrence was 0.40 episodes per 1000 admissions and an incidence of 66 per cent was observed in patients with serious underlying diseases, such as haematological malignancies and neoplasia. Thirty-seven patients had received cytotoxic and immunosuppressive therapy and showed a marked leukopenia, and whenever the leukocyte count fell below 2000/mm3, the prognosis was significantly worse. The most common portals of entry were the respiratory and gastrointestinal tracts. The overall mortality was very high (75 per cent) and mainly related to septic shock. Apart from the very high frequency of this complication (24 patients, 40 per cent of all cases), a typical clinical picture, distinguishing pseudomonas from other Gram-negative septicaemias, did not emerge.

Adolescent↗
PubMed1984

Distribution of ceftazidime in ascitic fluid.

The pharmacokinetics of ceftazidime were investigated in eight normal subjects and eight patients with ascites after intravenous administration of 1 g of the drug. Samples of blood and ascitic fluid were collected for 6 h after dosage, and urine samples were collected for 24 h. Pharmacokinetic data were calculated by using a one-compartment model. The apparent volume of distribution and half-life of elimination (t1/2 beta) in patients with ascites were approximately three times those in normal subjects. In contrast, renal clearance was greater in the normal subjects. With respect to ascites, the mean area under the concentration-time curve was 95.3 +/- 38.3 micrograms X h/ml. The mean ratio of the area under the concentration-time curve for ascitic fluid to that for plasma was 69.9% (+/- 38.2). These data show that ceftazidime rapidly diffuses into the peritoneal space, in which concentrations greater than 10 micrograms/ml were present for at least 6 h.

Adult↗
PubMed1982

Contribution of four markers of tubular proteinuria in detecting upper urinary tract infections. A multivariate analysis.

The presence of tubular involvement, as a marker for the detection of urinary tract infection (UTI) site, was examined in 19 patients with pyelonephritis and in 15 patients with cystitis or asymptomatic bacteriuria. The urinary excretion of four markers of tubular proteinuria, beta 2-microglobulin (beta 2M), lysozyme (LZ), lactic dehydrogenase isoenzyme V (LAD-5) and N-acetyl-beta D-glucosaminidase (NAG), was investigated. LAD-5 appeared particularly valuable for the early detection of upper UTI. However, the overall diagnostic accuracy appeared to be further strengthened using, besides LAD-5, one additional variable. A set of simple and noninvasive biochemical tests on urine samples can reliably help to identify the site of UTI.

Acetylglucosaminidase↗
PubMed1982

The kinetics of cefuroxime in ascitic and pleural fluid.

Adequate drug concentration at the infection site is a very important objective of antibiotic therapy. In this study we investigated the pharmacokinetics of the new methoximine, cefuroxime, in peritoneal and pleural fluids in 16 patients. After a 1-g dosage of cefuroxime, its concentration reaches a peak in ascitic fluid within 4-5 h. With a 2-g dose the peak level is reached in 2-3 h. After 5 h, cefuroxime concentration in ascites exceeds that in serum. Cefuroxime diffuses readily into the peritoneal space, where high concentrations (8-10 mcg/ml) are maintained for at least 6 h. Data on the kinetics in pleural fluid also seem to show high antibiotic diffusion rates, even if concentrations are never as high as those in blood at the same time following 1 g i.v. These favorable kinetic properties are probably due to low serum protein binding and to slow renal excretion.

Ascitic Fluid↗
PubMed1980

Diagnostic value and biological significance of antibody-coated bacteria in urine.

The incidence of antibody-coated bacteria (ACB) in the urinary sediments as an indication of the site of urinary tract infections (UTI) was investigated in 103 adult subjects with persistent bacteriuria by means of a direct immunofluorescence technique.ACB were found in 49 of 58 (84.5%) subjects with long-standing upper urinary tract obstruction and in 5 of 45 (11.1%) with lower UTI; this difference was statistically significant (X(2) = 51.79; P<0.001). The group with upper UTI was further subdivided according to renal function (patients with renal insufficiency had both bilateral obstruction and bilateral renal damage); 21 positive results were obtained in 27 (77.8%) patients with normal renal function, whereas 28 positive cases were observed among 31 (90.3%) patients with chronic renal insufficiency. Thus the degree of renal involvement also seemed to influence the outcome of the test. Within the group of lower UTI, a higher rate of ;false-positive' results was obtained in 14 patients with symptomatic long-standing infection (21.4%) than in 31 subjects with asymptomatic bacteriuria (6.4%). The three major immunoglobulin classes and the secretory component were studied in 42 cases. Of these, 29 were found to be positive for ACB. The constant presence of IgA and secretory component on the surface of ACB suggests that the secretory immune system plays an important role in UTI.

Antibody-Coated Bacteria Test, Urinary↗