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Biomedical subjects

M Mancini

Publications and source records attributed to M Mancini.

At least 289 records · Page 16Linked to original sources
PubMed1989

Erythrocyte sodium/lithium countertransport and renal lithium clearance in a random sample of untreated middle-aged men.

1. It has been proposed that the enhanced erythrocyte Na+/Li+ countertransport observed in many patients with essential hypertension could be a marker of abnormal renal proximal tubular function. We thus investigated the relationship of blood pressure and Na+/Li+ countertransport to an index of proximal tubular function such as renal Li+ clearance. 2. The study was carried out in a sample of 299 untreated male subjects (aged 21-59 years) randomly selected from a population at work. Na+/Li+ countertransport was measured in a representative sub-group of 176 men. 3. We did not detect statistically significant correlation of either blood pressure or Na+/Li+ countertransport (Vmax) with fractional excretion of Li+, while confirming the existence of a significant continuous association of blood pressure and body mass index with Na+/Li+ countertransport (P less than 0.01). 4. A sub-sample of 57 participants belonging to the lowest or the highest quintiles of Na+/Li+ countertransport distribution repeated the Li+ clearance study after moderate Na+ restriction. 5. Although fractional excretions of Na+ and Li+ were reduced on the low Na+ diet (both P less than 0.001), they did not differ significantly between groups. 6. Our results are at variance with the findings of a recent case-control study in a young age group and suggest that further studies are necessary before a conclusion can be drawn as to the suitability of Na+/Li+ countertransport as a marker of Na+ reabsorption in the renal proximal tubule.

Adult↗
PubMed1989

Red blood cell sodium-lithium countertransport, blood pressure, and uric acid metabolism in untreated healthy men.

The relationship of red blood cell (RBC) Na/Li countertransport to the renal handling of lithium and uric acid was investigated in a sample of 176 untreated men. Subjects in the upper quintile of the Na/Li countertransport distribution (n = 40), compared to those in the two lower quintiles (n = 72), had higher serum uric acid levels (0.34 +/- 0.06 v 0.29 +/- 0.05 mmol/L, P less than 0.001) and systolic blood pressure (131 +/- 19 v 123 +/- 16 mm Hg, P less than 0.02) and slightly lower fractional excretion of uric acid (7.5 +/- 1.5 v 8.4 +/- 2.6%, P less than 0.08). The lithium fractional excretion was not significantly related to either blood pressure or RBC Na/Li countertransport. The altered uric acid metabolism in individuals with high RBC Na/Li countertransport could be the expression of an abnormality of renal tubular function.

Biological Transport↗
PubMed1989

Adrenergic nervous system and left ventricular mass in primary hypertension.

A link between the activity of the adrenergic nervous system and left ventricular hypertrophy has frequently been found in hypertensives. In 16 patients with untreated primary hypertension of mild to moderate degree, we have evaluated the possible correlations between echocardiographic left ventricular mass (LVMe) and sympathetic nervous system activity, using pressor response to exogenous noradrenaline infusion, measurement of 24-h catecholamine urinary excretion and pressure response to ergometric exercise. Pressor response to noradrenaline infusion was significantly related to echocardiographic measures of left ventricular hypertrophy (correlation coefficients were: -0.60 for LVMe; -0.51 for septal thickness (ST); -0.51 for posterior wall thickness). Left ventricular mass was also related to systolic blood pressure measured during ergometric exercise (correlation coefficients were: 0.52 with LVM index, 0.51 with LVMe and 0.61 with ST). Arterial wall hypertrophy has been identified as being responsible for the vascular hyperreactivity in hypertension. A likely explanation of our findings is that the degree of left ventricular hypertrophy is associated with the degree of structural alterations of the resistance vessels and that the vascular impairment is responsible for the increased pressure response to noradrenaline.

Adult↗
PubMed1989

Atrial natriuretic peptides and tubular sodium handling during normal daily life in men.

The relationship between segmental renal tubular sodium handling (using the renal clearance of ingested lithium as a marker of proximal tubular sodium handling) and circulating plasma levels of atrial natriuretic factor (ANF) was studied in a sample of 295 untreated men drawn from a male population at work under their usual living conditions. Plasma ANF was positively and significantly related to sodium excretion at the distal nephron, indicating that this hormone interacts with a distal renal tubular site to influence the control of sodium excretion in man.

Adult↗
PubMed1989

Hereditary localized pruritus in affected members of a kindred with multiple endocrine neoplasia type 2A (Sipple's syndrome).

We describe a kindred with medullary thyroid carcinoma and phaeochromocytoma (MEN 2A or Sipple's syndrome) in which a cutaneous manifestation is only present in affected members. These members felt an intense itching in an area 5-10 cm in length and passing through the scapular region where, after long-term scratching, the skin appears hyperkeratotic and pigmented. Cutaneous biopsies proved negative for dermis nerve abnormality. This restricted itching strongly suggests dominant transmitted hereditary localized pruritus which was described many years ago in a family which was apparently free from inherited diseases. In the examined kindred this skin peculiarity was said to have appeared before the patients reached 10 years of age and, therefore, prior to the biochemical manifestation of the thyroid tumour. Three children of the last generation, aged 4 to 11 years, all of whom presented this cutaneous manifestation, were considered unaffected because of normal basal and stimulated calcitonin, but thyroid C-cell hyperplasia was recently proved in the eldest. In this MEN 2A kindred the presence of such a characteristic hereditary itch in affected members may be considered as a phenotypic marker giving advance warning of medullary thyroid carcinoma.

Adolescent↗
PubMed1989

Prolonged effect of alpha-interferon after discontinuance of treatment in chronic myelogenous leukemia patients.

14 patients out of a group of 73 affected by CML and treated with alpha-2-IFN, who had obtained hematological and cytogenetic response, were selected to be submitted to autologous BMT. In all patients the IFN treatment was interrupted to obtain an increase of the peripheral WBC necessary for its collection by means of leukapheresis. After a median time of 20.5 weeks from discontinuance of therapy, most patients are still under hematological disease control. Serially performed cell cultures have shown deeply and persistently reduced growth patterns; cytogenetic analyses have displayed Ph' mosaicism, but with a progressive increase in time of Ph' + cells. Such findings reveal that the effect of alpha-2-IFN in CML patients can be unexpectedly prolonged after discontinuance of treatment. A possible explanation might be found in the complexity of the biological mechanisms of action of IFN, thus giving this drug promising therapeutic prospects in the treatment of CML.

Adult↗
PubMed1989

Characteristics of the distribution of plasma atrial natriuretic peptides in a cross-sectional study of middle-aged untreated male workers.

The distribution of the plasma levels of atrial natriuretic peptide (ANP) and their statistical correlates were studied in a random sample of 306 untreated male workers in southern Italy. Plasma ANP was not normally distributed in the population sample, with values skewed to the right and significantly shifted from the normal Gaussian curve (p = 0.003). In a multivariate analysis, plasma ANP was independently and positively related to age (p less than 0.001), urinary sodium excretion (p less than 0.01), and inversely related to creatinine clearance (p less than 0.02).These variables explained more than 12% of the variability of plasma levels of ANP. These findings confirm, in a random sample of untreated male workers, the importance of age and renal function in predicting ANP levels in the plasma and emphasize the potential importance of ANP in the control of sodium excretion in humans under free living conditions.

Adult↗
PubMed1989

Cutaneous lichen amyloidosis associated with multiple endocrine neoplasia type 2A.

We have previously described a kindred with hereditary medullary thyroid carcinoma and pheochromocytoma (multiple endocrine neoplasia type 2A [MEN 2A]) with localized pruritic cutaneous manifestations present only in affected members. Although the initial skin biopsies reported did not show amyloidosis, subsequent skin biopsy results reported here have demonstrated amyloid which stained for keratin but not for calcitonin and established that this family represents an association of a rare autosomal dominant form of lichen amyloidosis with MEN 2A.

Adrenal Gland Neoplasms↗
PubMed1989

Enhancement of exogenous triglyceride removal following calcium channel blockade.

Adrenergic regulation of lipid metabolism is mediated by various intracellular messengers, including calcium ions. Little is known about the role of calcium in the catabolism of triglyceride-rich lipoproteins. Aim of this study was to investigate whether blockade of calcium influx across the cell membrane influences lipid metabolism in man. The calcium entry blocker nitrendipine was administered to 10 hypertensive, normolipidemic subjects for eight weeks at the dose of 10 mg b.i.d. An enhancement in plasma clearance of triglyceride was observed after nitrendipine administration: fractional removal rate of the triglyceride emulsion Intralipid increased by 22% (from 3.13 +/- 1.1 after placebo to 3.81 +/- 1.4% min after nitrendipine, p less than 0.03). Fasting serum triglyceride was not shifted (83 +/- 57 vs 84 +/- 37 mg/dl). Total serum cholesterol and cholesterol in high density lipoproteins were also unchanged during the study. No evidence of change in insulin response was detected. It is hypothesized that calcium plays a role in the modulation of lipoprotein lipase, the enzyme mainly responsible of the removal of exogenous triglyceride from plasma. Alternatively, the increase in the clearance rate of the triglyceride emulsion might be explained by the vasodilating activity of nitrendipine.

Adult↗
PubMed1989

Body weight and cardiovascular response to sympathetic stimulation in childhood.

The possible relationship between cardiovascular response to adrenergic stimulation and body weight has been studied in 166 eleven-year-old students (103 male, 63 female). Resting blood pressure (BP) by random-zero machine, heart rate (HR) and body weight (BMI) were measured four times in the school at 3-week intervals. On the third visit a mental arithmetic stress was carried out and a 24 h urine specimen was collected for the measurements of catecholamine excretion. On the fourth visit students carried out an isometric exercise (handgrip). Girls were more frequently found in the last quintiles of BMI (10/33 in the first vs 19/33 in the fifth). This might be due to a more advanced sexual maturation. BP at rest significantly increased with body weight (from 105/81 +/- 11/13 mmHg in the first to 119/87 +/- 10/12 in the fifth quintile). In each quintile no sex-related difference was observed in BP or HR. A marked cardiovascular response was observed during both tests without significant difference among quintiles. The 24 h urinary excretion of total catecholamines slightly increased with body weight (from 26.2 +/- 11 micrograms/24 h in the first to 34.5 +/- 19.5 micrograms/24 h in the fifth quintile). These data in a population of 11-year-old students therefore support the hypothesis that although BP at rest is influenced by BMI, the cardiovascular response to adrenergic stimulation is independent of body weight.

Blood Pressure↗
PubMed1989

Acute myeloblastic leukemia with t(8;21) following Philadelphia positive acute lymphoblastic leukemia.

A patient with Philadelphia positive (Ph'+) acute lymphoblastic leukemia (ALL), in remission for over 4 years, developed an acute myeloblastic leukemia (AML), M2-type. During the second disease, the blast cells displayed a typical t(8;21)(q22;q22) translocation, in the absence of the Ph' chromosome. This is the first observation in the same patient of two leukemias displaying different cell phenotypes and each associated to one of the most characteristic chromosome changes. Cytogenetic characteristics and clinical aspects of the diseases are suggestive for the occurrence of two independent leukemic processes.

Chromosomes, Human, Pair 21↗
PubMed1988

Presence of very low density lipoprotein compositional abnormalities in type 1 (insulin-dependent) diabetic patients; effects of blood glucose optimisation.

Plasma lipoprotein compositional abnormalities were investigated in eight normolipidaemic (plasma cholesterol less than 5.70 mmol/l; triglyceride less than 2.03 mmol/l) young male Type 1 (insulin-dependent) diabetic patients (before and after a short period of optimised blood glucose control) and in nine healthy control subjects, matched for sex, age and body mass index. Free and esterified cholesterol, triglyceride, phospholipids were assayed in all lipoprotein classes (VLDL, IDL, LDL) and in HDL subclasses (HDL2 and HDL3); apoB was measured only in very low density lipoproteins (VLDL). All VLDL constituents were increased in the diabetic group, the differences being more striking for apoB (6.0 +/- 1.1 mg/dl vs 2.0 +/- 0.1 mg/dl, p less than 0.02), free cholesterol (0.27 +/- 0.04 mmol/l vs 0.13 +/- 0.02 mmol/l, p less than 0.02) and esterified cholesterol (0.32 +/- 0.08 mmol/l vs 0.13 +/- 0.01 mmol/l, p less than 0.05). Also HDL subfractions showed differences between the two groups: all HDL2 constituents were increased, while in HDL3 only triglyceride was significantly increased (0.11 +/- 0.01 mmol/l vs 0.08 +/- 0.004 mmol/l, p less than 0.02). After two weeks of optimised blood glucose control all VLDL constituents were reduced and particularly: esterified cholesterol (-39%, p less than 0.02), free cholesterol (-37%, p less than 0.05), apoB (-35%, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Addition of chlorthalidone to slow-release nifedipine in the treatment of arterial hypertension: a controlled study versus placebo.

The use of calcium antagonists and diuretics in combination for treatment of hypertension is controversial. In a single-blind study 16 patients (8 men, 8 women, age range 39 to 62 years) with primary hypertension of mild to moderate degree were given slow-release nifedipine 20 mg twice daily for 6 weeks, thereafter either chlorthalidone 25 mg (Group A) or placebo (group B) daily was randomly added for a further 6-week period. Blood pressure (BP), heart rate, plasma renin activity (PRA), aldosterone, and 24 hour urinary electrolytes were evaluated. Nifedipine decreased supine BP from 159/92 +/- 16/8 to 151/89 +/- 10/6 mmHg in group A and from 162/94 +/- 20/12 to 145/85 +/- 14/6 mmHg in group B. A further fall to 139/84 +/- 7/6 mmHg (p less than .05) was observed after addition of chlorthalidone. PRA significantly increased with combined treatment compared to baseline (3.3 +/- 0.8 to 9.9 +/- 3.3 ng/ml/hr; p less than 0.05). A slight reduction of 24-hour urinary calcium was observed after the addition of chlorthalidone. These data indicate that the combination of nifedipine and chlorthalidone might be beneficial in the treatment of arterial hypertension.

Adult↗
PubMed1988

Abnormalities in serum lipoprotein composition in patients with premature coronary heart disease compared to serum lipid matched controls.

Serum lipoprotein composition was examined in 18 male patients (mean age 44 +/- 0.9 years) who had undergone coronary artery by-pass surgery because of premature coronary heart disease (PCHD) and in 18 control subjects, matched with patients for sex, age, body mass index and serum cholesterol and triglyceride. Cholesterol, triglyceride and apolipoprotein B (apo B) concentrations in very low density lipoprotein (VLDL) and in low density lipoprotein (LDL) did not differ in the two groups, but high density lipoprotein (HDL)-cholesterol was significantly lower in PCHD patients (P less than 0.02). Cholesterol/apo B, triglyceride/apo B and phospholipid/apo B ratios in VLDL were significantly higher in patients than in controls (P less than 0.05, P less than 0.01 and P less than 0.001, respectively). The relative VLDL enrichment in cholesterol was mainly due to the non-esterified moiety (P less than 0.01). These VLDL abnormalities as well as the low HDL-cholesterol suggest an impairment of VLDL catabolism in PCHD patients.

Adult↗