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Biomedical subjects

C Letizia

Publications and source records attributed to C Letizia.

At least 91 records · Page 5Linked to original sources
PubMed1995

Plasma endothelin-1 levels in normotensive and borderline hypertensive subjects during a standard cold pressor test.

Endothelin-1 (ET-1) is a potent vasoconstrictor peptide derived from endothelium. The presence of ET-1 in human vascular endothelium and in the plasma suggests that it may play a role in the regulation of vascular tone and blood pressure (BP) in humans. The aim of this study was to evaluate the behaviour of plasma ET-1 in 10 normotensives (average 36.3 +/- 14.8 years) and 10 borderline hypertensives (average 42.0 +/- 11.7 years) before, during and after a standard cold pressor test. We also evaluated the behaviour of heart rate and BP at the same time. Our results demonstrated that the baseline (-10 and 0 min) plasma ET-1 values were identical for the two groups (8.6 +/- 5.8 and 8 +/- 4.7 pg/ml in normotensives; 7.8 +/- 2.7 and 7 +/- 2.4 pg/ml in borderline hypertensives). A statistically significant increment was verified 10 min after exposure to cold in the borderline hypertensive group (12.1 +/- 5.1 pg/ml) compared with the normotensives group (6.8 +/- 4.5 pg/ml; P < 0.05). In conclusion, our study demonstrated that after 10 min of cold pressor stimulus an increase of circulating ET-1 levels was seen in borderline hypertensives.

Adult↗
PubMed1995

Serum angiotensin-converting enzyme levels in patients with recent-onset insulin-dependent diabetes after one year of low-dose cyclosporin therapy. IMDIAB Study Group.

Cyclosporin A (CyA) is today used for the treatment of autoimmune diseases and in the past was given also to patients with recent-onset insulin-dependent diabetes mellitus (IDDM). Hypertension is a major hazard in patients receiving CyA. In this study we have evaluated the effect of CyA administered to IDDM patients on blood pressure and serum angiotensin-converting enzyme (SACE), an endopeptidase that is an integral part of the renin-angiotensin and bradykinin systems. Sera from patients affected by recent-onset IDDM who were treated with CyA at the dose of 5 mg/kg body weight in addition to insulin therapy were included in the study (n = 13). Sera from 9 IDDM patients with the same clinical characteristics and followed up for 12 months represented the control group (insulin therapy only). SACE levels were measured at diagnosis and after 12 months. The results showed that SACE levels were elevated in IDDM patients at diagnosis and remained significantly high at 12 months in CyA-treated patients as compared to control patients (P < 0.006). Systolic and diastolic blood pressure were increased at 12 months in CyA-treated patients (p < 0.005 and p < 0.05, respectively). CyA therapy administered even at low doses to IDDM patients may increase SACE levels and also blood pressure. These findings should be considered when CyA is used for therapy of autoimmune diseases.

Adolescent↗
PubMed1994

Reduced serum angiotensin converting enzyme activity in children with congenital hypothyroidism.

In this study levels of serum angiotensin converting enzyme (SACE) were evaluated using colorimetric method in 24 children with congenital hypothyroidism, 28 children from an iodine deficient zone (14 euthyroid, 14 subclinically hypothyroid) and 21 normal children. In the children with congenital hypothyroidism SACE levels (28.15 +/- 6.67 nmol/ml/min) were significantly lower (p < 0.05) than SACE levels in normal children (33.87 +/- 7.00 nmol/ml/min) and in children from an iodine deficient zone (subclinical hypothyroid: 36.05 +/- 7.88 nmol/ml/min or euthyroid: 39.61 +/- 6.83 nmol/ml/min). No statistical difference in SACE levels was revealed in either normal subjects or children from an iodine deficient zone. SACE levels among all the groups were not shown to be different in relation to sex. Average TSH levels, as expected, were significantly higher (p < 0.05) in children with congenital hypothyroidism. The correlation between SACE and TSH levels did not demonstrate a statistical significance in any of the groups studied. In conclusion, our data demonstrated that levels of SACE were significantly reduced in children with congenital hypothyroidism.

Adolescent↗
PubMed1993

[Identification and preservation of the parathyroid glands in thyroidectomy using methylene blue].

The risk to the parathyroids in thyroid surgery is widely known. Postoperative parathyroid insufficiency occurs because of accidental devascularization of one or several glands, or infarction due to manipulation, or resection within the thyroid lobe. The prevention of this complication requires a careful surgical technique which limits any injury of the parathyroids. A simple, safe and cheap method to improve the identification of these glands is the preoperative intravenous infusion of methylene blue, that results in a distinct staining of the parathyroids. The authors describe their experience with this useful procedure which helps to reduce the incidence of hypoparathyroidism after total and near total thyroidectomy.

Adolescent↗
PubMed1993

A chronobiological approach to circulating levels of renin, angiotensin-converting enzyme, aldosterone, ACTH, and cortisol in Addison's disease.

This study deals with a chronobiological approach to the circadian rhythm of the renin-angiotensin-aldosterone system (RAAS) and the ACTH-cortisol axis (ACA) in patients with Addison's disease (PAD). The aim is to explore the mechanism(s) for which the circadian rhythmicity of the RAAS and ACA takes place. The study has shown that both the RAAS and ACA are devoid of a circadian rhythm in PAD. The lack of rhythmicity for renin and ACTH provides indirect evidence that their rhythmic secretion is in some way related to the circadian oscillation of aldosterone and cortisol. This implies a new concept: a positive feedback may be included among the mechanisms which chronoregulate the RAAS and ACA.

Addison Disease↗
PubMed1993

Amlodipine in ambulatory hypertensive patients: humoral and haemodynamic effects.

In order to evaluate the mid-term effects of amlodipine, a 1,4-dihydropyridine calcium antagonist, as well as its effects on the renin-angiotensin-aldosterone system (RAAS), on water and electrolyte balance, on urinary excretion of albumin (UAE) and on lipid metabolism, thirteen hypertensive patients (2 M, 11 F, mean age 54 years) were studied in the course of 24 weeks of therapy with amlodipine at 5-10 mg/day. Pre-therapy and periodically during therapy, the systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were recorded in the sitting orthostatic positions (2 measurements). Laboratory tests were performed at times O and at 24 wks with the patients fasting for at least 12 h in the recumbent position. The tests included: plasma renin activity (PRA), plasma aldosterone (PA), serum angiotensin converting enzyme (SACE), blood urea nitrogen (BUN), blood creatinine, plasma electrolytes (Na, K, Cl), triglycerides, total cholesterol (TC) and HDL-cholesterol (HDLC), along with 24-h urine samples (with sterile urine) to determine UAE. The results of this study demonstrate that SBP, DBP and HR were significantly reduced during the 24 wks of therapy. The water and electrolyte and renal function were not modified. After treatment the levels of TC were significantly reduced. No change was observed in the RAAS, while the mean levels of UAE were reduced though not significantly. In conclusion, amlodipine was shown to be effective for the therapy of hypertension; it does not cause reflex tachycardia even in mid-term therapy and was effective in reducing TC levels.

Adult↗
PubMed1993

Serum angiotensin converting enzyme activity in Crohn's disease and ulcerative colitis.

The relationship between serum angiotensin-converting enzyme activity (SACE) and inflammatory bowel disease was investigated in 30 patients with active Crohn's disease (CD) (CDAI > 150), 12 patients were not taking active medication, while 11 were on prednisone and 7 on mesalazine (5-ASA). Of 12 patients with active ulcerative colitis (UC), 4 patients were without treatment, 4 were on prednisone and 4 on mesalazine. Twelve patients with acute pulmonary sarcoidosis and 25 healthy subjects were studied. SACE levels in CD were not significantly different compared to healthy subjects and did not appear to be affected by the anti-inflammatory therapy. The average levels of SACE in UC were significantly higher than those of healthy subjects and CD (p < 0.005). Among the UC patients there was a trend for lower levels in the group treated with prednisone. In patients with active sarcoidosis SACE levels were extremely elevated and were significantly higher than in all other groups examined (p < 0.0001). The granulomatous inflammation in Crohn's disease differs from that of sarcoidosis, in which there is a striking elevation of angiotensin converting enzyme in serum. In other words, SACE levels seem to differentiate patients with active CD from patients with UC.

Adult↗
PubMed1992

Secondary aldosteronism documented by plasma renin and aldosterone circadian rhythm in subjects with kidney or heart transplantation.

The circadian rhythm (CR) of plasma renin activity (PRA), plasma aldosterone (PA), and plasma cortisol (PC) was investigated in 8 patients with kidney transplantation, and in 10 patients with heart transplantation. Ten clinically healthy subjects were studied as controls. The transplanted patients were all under cyclosporine treatment associated with prednisone (PDN). Time-qualified levels of PRA and PA were seen to be higher than normal in both groups of transplanted patients. The analysis of PRA and PA circadian rhythm provided evidence for a systematically higher level of within-day concentrations. The higher level of oscillation suggests the occurrence of a condition of hyperreninemic hyperaldosteronism. The higher levels of PRA and PA 24-h values show no periodicity. The finding suggests the abrogation of the rhythmic function for renin-aldosterone system. The disappearance of PRA-PA circadian rhythm seems to be attributable to a side effect of immunosuppressive therapy.

Adult↗
PubMed1992

[The behavior of serum angiotensin-converting enzyme in normotensive subjects, in subjects with essential hypertension and in subjects with primary hyperaldosteronism on the orthostatic test].

The results of this study demonstrate that only in healthy normotensive subjects during extended orthostatism that the renin-angiotensin-aldosterone system remains integral and is characterized by a significant increase in serum angiotensin-converting enzyme (SACE), plasma renin activity (PRA) and plasma aldosterone (PA). SACE modification do not seems to directly follow that of PRA (as shown by the absence of a direct correlation between SACE and PRA). In essential hypertension, the behavior of SACE seems to change, without demonstrating a significant increase in the mean levels of this enzyme. Finally in hypertension of known origin, such as primary hyperaldosteronism, the low levels of SACE in the recumbent position (not stimulated by orthostatism) seem to depend (by mechanism of negative biofeedback) on the increased serum levels of PA, which is moreover verified in the same group for PRA.

Adult↗
PubMed1992

Serum angiotensin converting enzyme in diabetic retinopathy.

Serum levels of angiotensin converting enzyme (SACE) were measured in 118 diabetic patients divided into the following four groups: 44 insulin-treated diabetic patients with severe retinopathy, 38 non insulin-treated diabetic patients with severe retinopathy, 18 diabetic patients, including both insulin-treated and non insulin-treated subjects with background retinopathy, 18 diabetic patients, insulin-treated and non insulin-treated without signs of retinopathy. Nineteen retinopathic patients non diabetic were also studied in order to verify whether SACE levels are altered when retinopathy is present independently from diabetes. The control group was composed of 44 normal subjects. When the data from the above six groups of subjects were submitted to statistical tests (one-way ANOVA, T-test of Bonferroni and test of Student-Newman-Keuls), the study yielded the following results: i) a remarkable difference between the SACE levels in healthy subjects and those in the three groups of diabetic retinopathic patients considered; ii) a non statistically significant difference of SACE levels between normal subjects and diabetic patients without retinopathy; iii) a non statistically significant comparison of SACE levels of normal subjects versus non diabetic retinopathic patients. Therefore, we concluded that while primitive diseases of the retina are not associated with an increase of SACE levels, yet when diabetes and retinopathy coexist, the SACE levels increase remarkably (in rather an independent way from the type of diabetes, the age of subjects, the stage of retinal disease and the daily average insulin dose), suggesting that most of the enzyme's increase originates from the endothelium of peripheral vasa, widely involved in most of the retinopathic diabetic patients.

Adult↗
PubMed1991

Circadian rhythm of T-lymphocyte subsets, cortisol and cyclosporin in kidney-transplanted subjects.

The present study deals with the 24-h changes in circulating lymphocyte subpopulations in eight subjects with kidney grafts established for 2 to 5 years and treated with cyclosporin. The control group consisted of ten age-matched clinically healthy subjects. The chronobiological analysis of time series documented that the circadian rhythm of T-lymphocyte subsets is undetectable in transplanted subjects. Cortisol rhythmicity persists, however, suggesting that the abolition of T-cell rhythmicity is not attributable to a desynchronisation of the adrenal cycle. Even though the therapy was combined with prednisolone, the abrogation of rhythmicity for T-lymphocyte subpopulations seems to be related to the immunosuppressive action of cyclosporin, as the plasma concentrations of the drug show no periodic variations along the 24-h span. Antirejection therapy of kidney-transplanted subjects could be adjusted so that cyclosporin is given at a time that would promote suppression of T-lymphocytes without altering their rhythmic performance.

Adult↗
PubMed1991

The effect of enalapril on nephrotic proteinuria and determination of serum angiotensin-converting enzyme before and after treatment.

In order to evaluate the effect of an ACE-inhibitor (enalapril) on nephrotic proteinuria in patients with primitive nephropathies, to determine the SACE before and after treatment and to compare the variation of SACE levels with the variations of proteinuria, seventeen patients were studied (5 F, 12 M) aged between 10 and 68 years. All patients were evaluated in basal conditions for creatinine clearance, protidaemia, proteinuria, SACE and serum electrolytes. All but one patient had a renal biopsy. After basal evaluation nine patients received enalapril, 10 mg/die, for two weeks. After one week SACE levels were re-evaluated, while the proteinuria was re-evaluated several times during the two weeks of treatment. The results obtained suggest (1) SACE levels are significantly higher in patients with nephrotic syndrome than in normal patients (21.14 +/- 8.37 nmol/ml/min; N.V.:15.60 +/- 4.73; M +/- s.d.; p less than 0.01); (2) proteinuria is unresponsive to the ACE-inhibitor action (varied from 8.00 +/- 2.70 g/24 h to 7.74 +/- 3.19 g/24 h, p = NS); (3) no correlation exists between the reduction of SACE levels and variations of proteinuria.

Adolescent↗
PubMed1991

Adrenocorticotropic hormone, beta-endorphin, cortisol, growth hormone and prolactin circulating levels in nineteen athletes before and after half-marathon and marathon.

Circulatory levels of ACTH, beta-endorphin (beta-Ep), prolactin (PRL), growth hormone (GH) and cortisol were evaluated in 19 volunteers athletes 48 h, 1 h before and soon after an international marathon (Romaratona 1988) and a national half-marathon. ACTH, beta-Ep and cortisol levels 48 h and 1 h before the half-marathon were similar, whereas 1 h before the marathon they were significantly elevated (p less than 0.01). Presumably the stress produced by the expectancy of the race induce a significant increase of the hormones of the hypothalamus-pituitary-adrenal axis in the very competitive marathon (Romaratona 1988). Moreover a remarkable increase of ACTH, beta-Ep, GH, PRL and cortisol circulating levels has been observed in the athletes after both runs, but in a different extend in relation not only to the duration and intensity of the muscular work but also to the agonistic effort: thus the hormonal increase was higher after the international marathon run than after the national half-marathon.

Adrenocorticotropic Hormone↗
PubMed1991

[Behavior of serum angiotensin converting enzyme in hyperthyroidism correlated to that of TSH].

The study examined the relations between serum levels of angiotensin-converting enzyme and those of thyroid-stimulating hormone in a group of hyperthyroid patients, and the respective therapy. The study continued for 12 months, from the onset of disease until remission. From an analysis of the results it was seen that levels of SACE and TSH during the first 4 months were significantly different to those in normal subjects: levels of SACE were increased, whereas TSH levels had fallen. This difference gradually diminished over the course of the following 8 months, and SACE and TSH values returned to within normal limits. The increment of SACE may depend on the presence of damage to the vascular endothelium within and surrounding the thyroid, in addition to intense vasodilation caused by the hyperthyroid state. The correlation between increased SACE levels and the course of disease is further confirmed by the fact that levels returned to within normal values during thyrostatic therapy; this was also observed in the case of TSH.

Adolescent↗
PubMed1991

Acquired factor VIII inhibitor in a patient with adenocarcinoma of the colon-rectum.

The presence of a circulating inhibitor of factor VIII was observed and described in several pathological conditions. In the present study we describe the case of a patient with a severe haemorrhagic syndrome caused by the presence of a circulating inhibitor of factor VIII discovered following abdominal surgery for an adenocarcinoma of the colon rectum. The haemorrhagic syndrome evolved independently from the course of the neoplastic disease.

Adenocarcinoma↗