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Biomedical subjects

M Capelli

Publications and source records attributed to M Capelli.

At least 55 records · Page 3Linked to original sources
PubMed1991

Evidence for a pathological reduction in brain dopamine metabolism in idiopathic hyperprolactinemia.

The role of brain catecholamine activity in the neuroendocrine regulation of the dopamine-PRL system in idiopathic hyperprolactinemia was investigated by high-performance liquid chromatography with electrochemical detector. We measured urinary dopamine, norepinephrine, epinephrine, vanillylmandelic acid, homovanillic acid, 3,4-dihydroxyphenylacetic acid and total 3-methoxy-4-hydroxyphenylglycol levels in 12 women with idiopathic hyperprolactinemia before and during either peripheral dopa-decarboxylase blockade, by carbidopa, or dopamine beta-hydroxylase blockade, by disulfiram. Homovanillic acid and 3,4-dihydroxyphenylacetic acid concentrations were significantly lower (p less than 0.001 and p less than 0.005, respectively) in patients with idiopathic hyperprolactinemia compared with those in 12 control subjects in the early follicular phase, whereas they were similar to those in the control subjects in the pre-ovulatory phase. Dopamine, norepinephrine, epinephrine, vanillylmandelic acid and 3-methoxy-4-hydroxyphenylglycol concentrations were similar to those of the control subjects in both phases of the cycle. During carbidopa administration the levels of all urinary catecholamines and metabolites were unchanged, except that of dopamine which dropped remarkably (p less than 0.001). During disulfiram administration dopamine, homovanillic acid and 3,4-dihydroxyphenylacetic acid concentrations increased (p less than 0.05, p less than 0.001 and p less than 0.005, respectively) and those of norepinephrine, vanillylmandelic acid and 3-methoxy-4-hydroxyphenylglycol decreased (p less than 0.05, p less than 0.001 and p less than 0.005, respectively), whereas epinephrine levels remained unaltered. These data support the existence of a quantitatively reduced brain dopamine activity in idiopathic hyperprolactinemia.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1991

Atrial natriuretic factor after dopamine infusion in healthy subjects and in congestive heart failure.

We evaluated the effects of dopamine (DA) infusion (1.5 micrograms.kg-1.min-1 for 60 min) on secretion of atrial natriuretic factor (ANF) in 10 healthy subjects and 10 patients with congestive heart failure (CHF) (NYHA Classes III and IV). During DA infusion plasma levels of ANF were significantly raised in healthy subjects while the high basal values of ANF in CHF patients were significantly reduced; this trend was also evident for plasma noradrenaline (NA) levels in both groups. Diuresis, natriuresis and glomerular filtration rate were significantly increased while blood pressure, heart rate and central venous pressure remained unchanged in both groups. These findings indicate that DA infusion may affect the release of ANF. Changes in plasma NA concentration suggest that the sympathetic nervous system may be involved in this phenomenon.

Adult↗
PubMed1990

Plasma atrial natriuretic factor in low output heart failure syndromes.

Plasma atrial natriuretic factor, aldosterone, renin activity, and antidiuretic hormone were studied in low output heart failure syndromes: cardiogenic shock in ten patients with acute myocardial infarction of the anterior wall (first group), hypovolemic shock after melena from peptic ulcer in ten subjects (second group), and hypotension with bradycardia syndrome in ten patients with acute myocardial infarction of the inferior wall (third group). Circulating atrial natriuretic factor in patients with cardiogenic shock (102.4 +/- 7.4 pg/ml) was significantly higher than in healthy volunteers matched for sex and age (8.4 +/- 0.3 pg/ml). In these patients there was a positive correlation between atrial natriuretic factor and central venous pressure values. Atrial natriuretic factor and central venous pressure values in the second and third groups were within normal range. Plasma aldosterone was high in all groups, plasma renin activity was elevated in the first and third groups, and high antidiuretic hormone was observed in the first and second groups. These findings indicate that in low output heart failure syndromes only hemodynamic changes affecting the atria stimulate atrial natriuretic factor release. No correlations were found between plasma atrial natriuretic factor and other hormones. In particular, high atrial natriuretic factor levels in the patients with cardiogenic shock did not inhibit release of aldosterone, renin, or antidiuretic hormone. It may be surmised that in these patients the hemodynamic effects override the inhibitory effects of atrial natriuretic factor.

Adult↗
PubMed1990

Characterization of obese women with reduced sex hormone-binding globulin concentrations.

Factors influencing sex-hormone binding globulin (SHBG) concentrations in obesity are poorly understood. Preliminary observations suggest that dietary lipids may be involved and there are data confirming a direct inhibiting effect of insulin. Since only some obese subjects show lowered SHBG levels, we performed this study with the aim of defining obese women with low SHBG (LSO) (2 SD above normal values) in comparison with those presenting normal globulin concentrations (NSO). These groups were selected from a larger group of obese women with a history of normal menses and aged less than 40 years. An age-matched group of normal weight healthy women served as controls. Both LSO and NSO had similar body mass index and percentage body fat, but the waist to hip girth ratio (WHR), an index of body fat distribution, was significantly higher in LSO (0.88 +/- 0.04) than in NSO (0.81 +/- 0.09; P less than 0.05). Gonadotropin and androgen concentrations were similar in both groups, whereas estrone (E1) levels were higher in LSO (32.8 +/- 15.8 pg/ml) than in NSO (19.4 +/- 6.2 pg/ml; P less than 0.05; controls: 23.5 +/- 7.8 pg/ml; P less than 0.05). Moreover, compared to NSO, LSO women had significantly higher glucose-stimulated insulin and C-peptide levels. Partial regression analysis revealed significant correlation coefficients between SHBG, stimulated insulin values (r = -0.38; P less than 0.05) and WHR (r = 0.40; P less than 0.005). Therefore, compared to NSO, LSO women have distinctive clinical and endocrine characteristics, namely more pronounced hyperinsulinemia, higher E1 concentrations and a central type body fat distribution.

Adult↗
PubMed1990

Plasma atrial natriuretic factor in patients with acute myocardial infarction.

Plasma atrial natriuretic factor (ANF), renin activity (PRA), aldosterone and antidiuretic hormone (ADH) were determined in 16 patients with uncomplicated acute myocardial infarction (AMI) for 7 days in all patients and in six patients for 8 more days. Echocardiograms were performed and central venous pressure (CVP) was measured on the 2nd, 7th and 15th days. On admission, plasma ANF was higher in patients with AMI (129.8 +/- 70.6 pg ml-1, mean +/- SD) than in healthy volunteers (50.6 +/- 10.0 pg ml-1) (P less than 0.05). Arterial pressure, heart rate, CVP were normal. Left atrial (LAD) and left ventricular diameters (LVDD) were increased in six patients. Ejection fraction (EF) was reduced in all. A significant inverse relationship between ANF and EF was observed. Patients with EF less than or equal to 45%, high LAD and LVDD had the highest plasma ANF and showed steady high plasma ANF for 15 days. Patients with EF greater than 45%, normal LAD and LVDD had elevated plasma levels only for 10 days, rising significantly on days 3-7 after admission. PRA and ADH values were normal throughout the study, whereas aldosterone was above the normal range only on admission. These findings suggest that the reduction in myocardial contractility induced by the infarction may account for the rise in ANF secretion via increased left atrial pressure or left atrial dilatation.

Adult↗
PubMed1990

Ketoconazole therapy for women with acne and/or hirsutism.

The effects of ketoconazole, a synthetic imidazole derivate, were evaluated in 42 women affected by acne (17 cases) and/or hirsutism (36 cases) treated with 400 mg/day for 3-6 months. Androstenedione, total and free testosterone, 5 alpha dihydrotestosterone and dehydroepiandrosterone levels progressively dropped during treatment while 17 alpha hydroxyprogesterone, estradiol, ACTH, cortisol, LH and FSH levels increased. Dehydroepiandrosterone sulfate decreased only towards the end of treatment, while estrone, sex hormone binding globulin, and PRL remained unchanged. Daily mean +/- SD rate of hair growth, measured by a special image analysis processor, decreased within 3 months of therapy from 0.258 +/- 0.058 to 0.184 +/- 0.039 mm/day (P less than 0.02) and mean +/- SD hair diameter from 0.123 +/- 0.015 to 0.110 +/- 0.013 mm (P less than 0.05) together with decreasing hormone levels. The therapeutic effects of ketoconazole on hirsutism was evident at 6 months in only 14 subjects, while no significant change in hirsutism score was recorded in 22 women who failed to complete the therapy. Acne improved in all cases. Several side effects and complications arose during treatment, such as headache, nausea, loss of scalp hair, hepatitis, and biochemical changes. Even though ketoconazole improves hyperandrogenism, only selected patients are eligible for treatment as scrupulous monitoring is required.

Acne Vulgaris↗
PubMed1990

Direct detection of a missense mutation causing severe hemophilia A by PCR amplification and fluorescence scanning.

The amplification of Factor VIII gene-specific sequences, obtained by polymerase chain reaction, was used for hemophilia A carrier detection. Exon 24 sequences were employed in the carrier status determination of a missense mutation causing severe hemophilia A in two unrelated patients. After agarose gel electrophoresis, the digested DNA was subjected to quantitative determination of fluorescence. This technique significantly improves the digest analysis.

Base Sequence↗
PubMed1990

[Effects of dopamine infusion on the release of atrial natriuretic factor].

We evaluated the effects of dopamine infusion (1.5 micrograms/Kg/min for 60 min) on secretion of atrial natriuretic factor before raised diuresis could affect extracellular fluid volume and hence peptide release. We investigated ten healthy subjects without cardiovascular, renal or endocrine disease and ten patients with congestive heart failure (New York Heart Association Classes III and IV). The study protocol required four 30 minute clearance periods: 1st basal, 2nd during placebo, 3rd and 4th during dopamine infusion. We measured diuresis, natriuresis, glomerular filtration rate, blood pressure, heart rate, central venous pressure and plasma concentrations of atrial natriuretic factor, noradrenaline, renin activity, aldosterone and antidiuretic hormone. Blood samples were drawn at the midpoint of each clearance period after measuring blood pressure, heart rate and central venous pressure. Atrial natriuretic factor was determined by radioimmunoassay after chromatographic extraction, noradrenaline was measured fluorometrically while plasma renin activity, aldosterone and antidiuretic hormone concentrations were obtained by radioimmunoassay. During dopamine infusion plasma atrial natriuretic factor plasma levels were significantly raised in healthy subjects while high basal values of the peptide in patients with congestive heart failure were significantly reduced; this trend was also evident for noradrenaline levels in both groups. Plasma renin activity, aldosterone and antidiuretic hormone values remained unchanged in healthy subjects, but plasma renin activity and aldosterone levels dropped significantly in congestive heart failure patients. Diuresis, natriuresis and glomerular filtration rate were significantly increased while blood pressure, heart rate and central venous pressure remained unchanged in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

Peripheral hemodynamic and humoral effects of oral zofenopril calcium (SQ. 26,991) in patients with congestive heart failure.

In 14 patients with congestive heart failure (CHF) of various grade (NYHA class 2-4) the effects of zofenopril calcium (SQ 26,991) on blood pressure and forearm circulation were studied by venous occlusion plethysmography. Changes in plasma renin activity (PRA), aldosterone, Atrial natriuretic factor (ANF) and arginine-vasopressin (AVP) were also measured. Two hours after oral administration of 7.5 mg of zofenopril we observed a decrease in blood pressure, heart rate, and forearm vascular resistance along with an increase in venous distensibility. Zofenopril also decreased ANP levels in a manner directly related to peripheral venodilatation (r = .64; P less than .05) and modified arginine-vasopressin (AVP) proportionally to the fall in blood pressure observed in response to drug administration (%SBP/%AVP: r = .64, P less than .05; %DBP/%AVP: r = .67, P less than .05). Hemodynamic and humoral responses to zofenopril occurred without any significant unwanted adverse reaction, even in patients with greater pressor reduction. We conclude that oral acute zofenopril administration, in patients with congestive heart failure, causes an arterial and venous forearm vasodilatation which is probably involved in the acute changes in plasma levels of ANF and AVP observed after drug administration.

Administration, Oral↗
PubMed1989

High concentrations of catecholamines in human hypothalamic-hypophysial blood.

While the hypothalamic-hypophysial portal system has been extensively studied in laboratory animals, equivalent studies have not been performed in humans. Here, we present an experimental procedure for collecting suprapituitary blood in man. To solve the question on the origin of such blood we investigated specific markers of hypothalamic secretory activity: the catecholamines (CAs). We found (a) norepinephrine (NE), dopamine (DA), and epinephrine (E) concentrations from approximately 1.5 to 2.5, 3.5 to 4.5, and 6- to 10-fold higher, respectively, in suprapituitary than peripheral blood, (b) different NE/DA and NE/E ratios in favor of DA and E in suprapituitary blood, and (c), a complete (100%) group separation (suprapituitary vs. peripheral) when discriminant analysis included only DA and E. These data indicate that suprapituitary blood composition is different from that of the peripheral blood, and is particularly rich in CAs and claimed differences between DA and E release on one hand and NE release on the other in suprapituitary blood also are observed. We advance the hypothesis of a hypothalamic source of such amines draining via median eminence into portal vasculature, and name this blood "hypothalamic-hypophysial blood." Besides serving as "classical" neurotransmitters, CAs may also have a direct neurohormonal role in the regulation of the human hypothalamic-hypophysial function.

Adult↗
PubMed1989

[Atrial natriuretic factor in acute atrial hyperkinetic arrhythmia and chronic atrial fibrillo-flutter].

The aim of this paper was to study atrial natriuretic factor, plasma renin activity and antidiuretic hormone values during paroxysmal atrial arrhythmias with different ventricular rates before and after pharmacological cardioversion and during chronic atrial flutter-fibrillation. The study was carried out: 1) during acute arrhythmias (atrial flutter-fibrillation or supraventricular tachycardia) and after restoration of normal sinus rhythm in 2 patients without heart disease, in 13 with chronic heart disease and in 6 with acute myocardial infarction; 2) during chronic atrial flutter-fibrillation in 5 patients with chronic ischemic heart disease, without congestive heart failure. Atrial natriuretic factor, aldosterone, plasma renin activity and antidiuretic hormone values were measured by radio-immunoassay. During paroxysmal atrial arrhythmias atrial natriuretic factor levels were higher than normal in all patients, particularly in those with supraventricular tachycardia. Most of the aldosterone measurements were above the normal range. As far as plasma renin activity and antidiuretic hormone values are concerned, levels higher than the normal range were found in the patients with severe hemodynamic impairment. Central venous pressure was above normal in all patients except in the 2 without heart disease, and there was a positive correlation between atrial natriuretic factor and central venous pressure values. After restoration of normal sinus rhythm atrial natriuretic factor values returned to normal except in acute myocardial infarction patients, in 1 chronic ischemic heart disease patient with congestive heart failure and in 3 patients with mitral valve disease. In all patients with chronic atrial flutter-fibrillation and in 5 patients with acute atrial flutter-fibrillation and low rate, above normal atrial natriuretic factor values were found with normal central venous pressure values. Atrial distension due to high central venous pressure values, lack of atrial contraction and rhythmic detension of the atrial stretch receptors, may be considered the major stimuli responsible for atrial natriuretic factor release during acute paroxysmal atrial arrhythmias and atrial flutter-fibrillation with low ventricular rate, respectively.

Acute Disease↗
PubMed1989

[Atrial natriuretic factor in cardiogenic shock, in hypovolemic shock and in the bradycardia-hypotension syndrome following acute myocardial infarction].

The aim of this paper was to study plasma atrial natriuretic factor, renin activity, aldosterone and antidiuretic hormone in low-output heart failure syndromes such as cardiogenic shock, hypovolemic shock and hypotension with bradycardia syndrome. A total of 30 patients were investigated: 10 with cardiogenic shock due to acute myocardial infarction of the anterior wall (systolic and diastolic blood pressure 56.0 +/- 3.7/40.5 +/- 2.0 mmHg; heart rate 119.7 +/- 1.2 beats/min; central venous pressure 16.2 +/- 0.6 cmH2O) (I group), 10 with hypovolemic shock induced by melena in peptic ulcer (systolic and diastolic blood pressure 74.5 +/- 1.5/57.5 +/- 1.7 mmHg; heart rate 111.0 +/- 1.4; central venous pressure 6.3 +/- 0.5 cmH2O) (II group), 10 with hypotension with bradycardia syndrome which occurred in patients during acute myocardial infarction of the inferior wall (systolic and diastolic blood pressure 71.9 +/- 2.0/58.0 +/- 2.6 mmHg; heart rate 52.0 +/- 2.2 beats/min; central venous pressure 4.6 +/- 0.4 cmH2O) (III group). Plasma atrial natriuretic factor values were measured using radioimmunoassay after chromatographic pre-extraction; plasma renin activity, aldosterone and antidiuretic hormone values were calculated using radioimmunoassay. Circulating atrial natriuretic factor was significantly (p less than 0.01) higher in patients with cardiogenic shock (102.4 +/- 7.4 pg/ml) than in healthy volunteers (8.4 +/- 0.3 pg/ml). In the former there was a positive correlation between atrial natriuretic factor and central venous pressure values. Atrial natriuretic factor and central venous pressure values in the IInd and IIIrd groups of patients were in the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Changes in plasma myoglobin levels in ischemic heart disease].

The aim of the present study is to evaluate the real need and the sensitivity of serum myoglobin levels as an early index for the diagnosis of acute myocardial infarction. A total of 62 patients (38 suffering from acute myocardial infarction, 16 from "angina pectoris", 8 from heart failure) and 20 healthy volunteers were included in the study. The patients with acute myocardial infarction were divided in 3 subgroups according to the time passed between the beginning of the pain and their admittance to our Department (Coronary Care Unit), that was, less than 6 hours, between 6 and 12 hours, between 12 and 24 hours. Among the patients with "angina", 8 presented spontaneous crisis whereas 4 had crisis only during treadmill test. 8 of the healthy volunteers received intramuscular injections of physiological solution every 12 hours during the 3 days preceding the study. In all subjects serum myoglobin level were measured by radioimmunoassay; in patients with acute myocardial infarction serum CK and MBCK levels with enzymatic method were measured too. No variation of plasma myoglobin levels was seen in patients with angina, neither in healthy volunteers had they received or not intramuscular injections. The low increase in plasma myoglobin levels observed in patients with heart failure might be due to a deficit of renal function. Serum myoglobin levels were significantly elevated in all the patients with acute myocardial infarction, whereas plasma CK and MBCK levels were significantly high only 6 hours after the necrosis. In myocardial infarction the levels of myoglobin rise during the first hours, peak at 10 hours and return to normal in 20 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1988

Weight loss and sex steroid metabolism in massively obese man.

To evaluate the effect of weight loss and diet therapy on plasma sex hormone behavior in male obesity, 9 men with a BMI of 43.4 +/- 6.3 participated in an 8-week semistarvation program [whose energy content ranged from 320 to 500 k calorie/day (proteins 44 to 60 g and carbohydrates 54 to 81 g per day)] followed by a two-week hypocaloric (1000 k calorie/day) refeeding. In basal conditions, obese patients presented higher estrogen and lower dehydroepiandrosterone sulphate, testosterone (total and free) and sex-hormone binding globulin concentrations with respect to a group of control normal-weight subjects. Cumulative weight loss was 23.9 +/- 3.6 kg after semistarvation and 24.4 +/- 4.8 kg after refeeding (p = NS). A significant increase in testosterone, free testosterone and dehydroepiandrosterone sulfate was observed throughout the study, irrespective of dietary intake. A transient increase occurred in estrone levels while 17B-estradiol did not change. Gonadotropins and sex-hormone binding globulin values remained unaltered. No relationship was found between sex hormones and dietary energy content or composition. Daily urine free cortisol, which was used as a parameter of adrenal function, fell approximately 50% during semistarvation but returned to baseline values after refeeding. These results show that in massively obese patients weight loss per se may partially reverse sex hormone abnormalities but not sex-hormone binding globulin concentrations. It remains to be determined whether the return to "normal weight" can normalize steroid metabolic derangements in the obese man.

Adult↗
PubMed1988

Evidence for a hypothalamic alteration of catecholamine metabolism in polycystic ovary syndrome.

The role of brain catecholamine (CA) activity in the neuroendocrine regulation of the GnRH-LH system in polycystic ovary syndrome (PCO) was investigated by high-performance liquid chromatography (HPLC) with electrochemical detector. We measured urinary dopamine (DA), noradrenaline (NA), adrenaline (A), vanillylmandelic acid (VMA), homovanillic acid (HVA), 3,4-dihydroxyphenylacetic acid (DOPAC) and total 3-methoxy-4-hydroxyphenylglycol (MHPG) levels in a group of 12 women with PCO before and during peripheral dopa-decarboxylase blockade, by carbidopa. HVA and DOPAC concentrations were significantly lower (P less than 0.001 and P less than 0.005, respectively) in PCO patients compared with twelve control subjects in early follicular phase, whereas total MHPG concentrations and MHPG/VMA ratio were significantly higher (P less than 0.005) in PCO patients. Moreover, HVA and DOPAC concentrations in PCO patients were similar to those of the control subjects in preovulatory phase, while MHPG concentrations remained higher in PCO patients (P less than 0.01). DA, NA, A and VMA concentrations were similar to those of control subjects in both phases of the cycle. During carbidopa administration the concentrations of all urinary CAs and metabolites were unchanged, except those of DA which dropped markedly (P less than 0.001). These data suggest that (1) an altered central catecholamine metabolism consisting of DA deficiency and NA excess is present in PCO, and (2) the site of DA deficiency may be located in the hypothalamus.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1988

Urinary excretion rate of C-peptide in fed and fasted obese humans.

The aim of the study was to evaluate the reliability of urinary excretion rate of C-peptide as a marker of B-cell function during fasting. Ten obese subjects of both sexes fasted for 5 days. Diurnal serum C-peptide was collected before and on the 5th day; morning serum samples (for glucose, insulin and C-peptide) and 12-h urine samples (7.00 to 19.00 h) were collected daily. Body weight decreased from 138.7 +/- 15.9 to 132.9 +/- 15.6 kg. Morning glucose, insulin (-40%) and C-peptide (-50%) fell significantly throughout the study. Mean diurnal C-peptide values were 2.19 +/- 0.69 nmol/l before and 0.60 +/- 0.19 nmol/l after fasting (P less than 0.0001) and its secretion rate was 909.4 +/- 297.9 and 244.4 +/- 83.9 nmol/12 h (P less than 0.005), respectively. Excretion rate of C-peptide fell progressively from basal (11.2 +/- 4.2 nmol/12 h) to a nadir value of 1.3 +/- 0.8 nmol/12 h (P less than 0.0005); similarly, the C-peptide to creatinine clearance ratio fell from 0.062 +/- 0.035 to 0.028 +/- 0.015 (P less than 0.05). These results indicate that fasting modifies renal metabolism of C-peptide thus creating several complications in the quantitative interpretation of urinary levels as an index of its secretion rate from the B-cell.

Adult↗
PubMed1987

[Effect of guar on plasma lipids and on the biological activity of insulin in patients with type 2 diabetes mellitus].

10 patients with type 2 diabetes mellitus, in stable weight and diet therapy, followed a 2 months nutritional supplementation with guar, 15 g/day. Their previous nutritional and pharmacological therapy was not modified throughout the study. No changes occurred in body weight or major parameters of metabolic control. However, a significant fall occurred in fasting plasma, total and LDL cholesterol, and apolipoprotein B concentrations. Insulin sensitivity, measured by the "steady state plasma glucose", obtained after a 150 min glucose-insulin-somatostatin infusion, improved in all patients but two. A significant correlation was observed between steady state plasma glucose variations, the glycosylated haemoglobin A1c (r = 0.70; p less than 0.005), total (r = 0.77; p less than 0.001), and LDL cholesterol (r = 0.69; p less than 0.005) and apolipoprotein B concentrations (r = 0.75; p less than 0.005).

Adult↗