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D Fonzo

Publications and source records attributed to D Fonzo.

69 records · Page 4Linked to original sources
PubMedDate not supplied

[Intact whole bioactive parathormone: problems arising from comparing different methods].

BACKGROUND: Parathyroid hormone (PTH) has important applications in the nephrological clinical practice. Because assays of Intact PTH (I-PTH) are liable to interferences by N-truncated fragments, a novel method for whole-(1-84) PTH has been proposed. This study is aimed at comparing the latter with some of the previous I-PTH assays. For each method the results are referred to pertinent markers of mineral metabolism. METHODS: We enrolled 171 subjects, including 56 healthy controls (C), 65 calcium stone- formers (CaSF), 40 haemodialysis patients (HD), 10 with primary hyperparathyroidism (PHP). On blood samples we measured: I-PTH by four methods (N-Tact, Advantage, Elecsys, Scantibodies), whole-(1-84) PTH, defined as CAP (Cyclase Activating PTH), total and ionised calcium, phosphate, vitamin D, osteocalcin and Crosslaps. The difference between I-PTH and CAP Scantibodies is defined as CIP (Cyclase Inhibiting PTH). RESULTS: Despite relating to each other (r>0.97) PTH values varied remarkably among methods. For all methods, the reference intervals differed from those provided by the producer. Assuming these new ranges, 10 CaSF had over-range values not always associated with abnormalities of mineral metabolism. One of the PHP patients was normal for I-PTH with 2/4 methods. In HD the differences among methods were even greater, there were inverse (p<0.05) and direct (p<0.001) relationships with ionised calcium and osteocalcin-crosslaps, respectively. The CAP/CIP ratio was lower in low bone turnover patients, but the two subgroups widely overlapped. CONCLUSIONS: This study indicates that the reliability of I-PTH assays is still unsatisfactory, and none of the four methods emerged as the best. Assay for CAP only improves diagnostic efficiency, whereas the CAP/CIP ratio does not exhibit powerful discriminating capacity. Our suggestion is that each Centre should establish its own reference ranges. PTH assay should always be coupled with measurements of other markers of mineral metabolism as well as renal function.

Adult↗
PubMedDate not supplied

[ACE inhibitors and vagal activity: the effect of captopril and lisinopril on cardiovascular reflexes].

The influence of the ACE-inhibitors captopril and lisinopril on parasympathetic activity in normotensive subjects was evaluated. Three cardiovascular tests which explored chiefly parasympathetic function (deep breathing, lying to standing and Valsalva test) were performed in 10 normotensive volunteers (mean age 26.1 years) in both basal conditions and after four days of treatment with either captopril (25 mg twice a day) or lisinopril (20 mg once a day). Mean blood pressure was not influenced by captopril, whereas it was significantly lowered with lisinopril (from 94.4 +/- 6.8 to 88.7 +/- 5.7 mmHg; p < 0.05). Neither drug interfered with heart rate or with the results of the deep breathing and Valsalva tests. The 30/15 ratio, an index of heart rate variability during the lying to standing test, significantly worsened after assumption of both captopril (from 1.37 +/- 0.18 to 1.21 +/- 0.14; p < 0.05) and lisinopril (from 1.31 +/- 0.17 to 1.20 +/- 0.11; p < 0.05). Although our subjects had a lisinopril-induced drop in blood pressure, their heart rate remained steady. This finding confirms previous studies reporting the lack of reflex tachycardia during ACE-inhibition. The slight effect of ACE-inhibitors on the results of deep breathing and Valsalva tests suggests that such drugs do not directly stimulate vagal activity; the significant decrease of the 30/15 ratio may be due to a functional impairment of the baroreflex mechanism.

Adult↗
PubMedDate not supplied

Circadian rhythm of urinary 17-hydroxycorticosteroids during metyrapone-induced ACTH release in normal subjects.

The circadian rhythm of urinary 17-OHCS was studied in nine normal subjects before and after oral metyrapone administration (750 mg every 4 hrs over a period of 24 hrs). The test was carried out twice in each subject with a shift of 12 hrs in the time of first administration (0800-test and 2000-test). For data from serial measurements of steroid metabolites on urine collected at 2-h intervals, the least squares fit of a 24-h cosine curve allowed the demonstration of a rhythm both in control conditions and during the 48-h span following metyrapone administration. Circadian acrophases were substantially similar. Total urinary 17-OHCS output in the first 24-h day following metyrapone was higher in the 2000-test as compared with the 0800-test (P less than .001). Conversely, in the second 24-h day, higher values were obtained in the 0800-test (P less than .025). The combined 48-h exretion, however, was identical in the two groups. The results suggest a time-limited action of metyrapone upon the pituitary-adrenal axis, since the increased excretion of 17-OHCS seems essentially accounted for by an exaggerated impulsive phase of ACTH secretion during the early morning hours.

17-Hydroxycorticosteroids↗
PubMedDate not supplied

[Analysis of seminal fluid: modern aspects of an old examination].

Semen analysis stands as the most widely employed test for the diagnosis of male infertility. Subjectivity of evaluation and intra-individual variations of sperm concentration and motility are major limitations of this technique. Intra-individual variations are due to spontaneous circannual rhythmicity, to collection artifacts or to several environmental, physiological and pathological factors. The diagnostic and prognostic usefulness of semen analysis is related to strict compliance with the guidelines recently suggested by the World Health Organization. In recent years, the development of computerized systems provides an objective and rapid method for semen analysis, suitable for the study of more sophisticated parameters of sperm motility. Electron microscopy should be performed for the evaluation of ultrastructural abnormalities of spermatozoa in men with infertility of uncertain origin.

Artifacts↗
PubMedDate not supplied

Autonomic neuropathy in non-insulin-dependent diabetic patients: correlation with age, sex, duration and metabolic control of diabetes.

The aim of this study has been to assess the prevalence of autonomic neuropathy among non-insulin dependent diabetic patients, and to determine whether a correlation could be found between autonomic impairment and the following: age, sex, duration of diabetes, body mass and metabolic control. Two hundred and twenty one non-insulin dependent patients were submitted to four cardiovascular tests: heart rate response to deep breathing and to standing up; blood pressure response to handgrip and to standing up. Sixty six percent of patients showed at least one abnormal cardiovascular response. The prevalence of autonomic impairment was higher in non-insulin dependent than in insulin-dependent diabetics. Patients were grouped according to the extent of autonomic impairment: absent (33.5%), early (27.6%), definite (3.6%), severe (4.5%). An atypical pattern (abnormality of blood pressure responses in absence of a definite abnormality of heart rate responses) was found in 30.8% of patients. Heart rate responses correlated significantly with age (p less than 0.001). No correlation between test results and duration was found in the multivariate analysis. The tests' results did not correlate with metabolic control or body mass index. Patients with symptoms of autonomic neuropathy had values for heart rate response to deep breathing and to standing significantly lower than those without (p less than 0.05).

Adult↗
PubMedDate not supplied

Autonomic nervous activity in obese subjects before and after caloric restriction.

The heart rate response to deep breathing (DB test) and standing (30:15 r test) and the blood pressure response to standing (LS test) and sustained handgrip (HG test) were assessed in 19 obese subjects and 15 age matched lean controls. The results of DB, 30:15 r and LS tests were not significantly different in both groups. The diastolic blood pressure increase during handgrip was significantly higher in obese than in control subjects. After a period of caloric restriction the tests were repeated in 9 patients who had obtained a weight loss of at least 5 kg: a significant decrease in heart rate, diastolic blood pressure and 30:15 r results was observed, whereas the caloric restriction did not cause significant variations in the results of DB, LS and HG tests. Our results suggest that in obese patients some autonomic nervous changes can occur before and after weight loss.

Adult↗
PubMedDate not supplied

Autonomic neuropathy and sexual impotence in diabetic patients: analysis of cardiovascular reflexes.

Four cardiovascular tests exploring autonomic nervous function (Deep Breathing, 30:15 ratio, Lying to Standing, Hand Grip) have been performed in 38 diabetic patients with erectile failure (mean age 53.2 years, range 34.5-60.5) and in 35 diabetic subjects without sexual dysfunctions (mean age 52.8 years, range 45-60.5). In our study Deep Breathing test was abnormal in 21 patients with erectile failure (55.3%) and in 9 patients without sexual dysfunction (25.7%) (P less than 0.05). Seven patients with sexual impotence (18.4%) and 2 subjects without sexual dysfunction (5.7%) showed abnormal results of 30:15 ratio test. The Lying to Standing test was not abnormal both in impotent and in non impotent subjects, while the Hand Grip test was abnormal in 7 patients with impotence (18.4%) and in 8 patients without sexual dysfunction (22.9%). Results obtained from Deep Breathing test were significantly lower (P less than 0.01) in impotent (10.25 +/- 6.10 beats/min) than in non impotent patients (14.63 +/- 6.85 beats/min). Lower 30:15 ratios were also found in patients with erectile failure (1.09 +/- 0.10 vs 1.12 +/- 0.09). The tests exploring the sympathetic function did not show any difference between the two groups of patients. The present study confirms the major role of parasympathetic impairment in the pathogenesis of sexual dysfunctions in diabetic men. Cardiovascular tests can be a first-step diagnostic tool in the assessment of diabetic impotence.

Adult↗
PubMedDate not supplied

Immunogenicity of a killed E. coli 0111:K58 vaccine administered orally to children.

A killed E. coli 0111:K58 vaccine was administered by the oral route to 16 children ranging from 3 months to 7 years of age. The antibody response was measured at different times after the vaccination through the titration of agglutinating antibodies in serum and in fecal extracts, and the detection of specific IgA immunoglobulins in the intestinal content. All vaccines developed antibody response detectable both inserum and in fecal samples. Coproantibodies tended to appear earlier and to attain higher titers than circulating antibodies; they were all least in part IgA immunoglobulins, since the content of specific IgA in the fecal extracts was proportional to the agglutinating titer.

Administration, Oral↗
PubMedDate not supplied

[Oral immunization of human adult volunteers using a trivalent coli-vaccine].

Oral vaccination of 19 human adult volunteers with a killed trivalent E. coli vaccine induced an antibody response detectable either in sera and feces. Production of specific IgA immunoglobulins in the intestine was also observed. Antibody titres reached the highest levels 5-10 days after vaccination and were still detectable in the majority of volunteers about 2 months later.

Administration, Oral↗