Search PubMed⌕ Search

Biomedical subjects

M Volpe

Publications and source records attributed to M Volpe.

At least 217 records · Page 12Linked to original sources
PubMed1977

Effects of guanethidine on histamine release during reflex vasodilatation in the dog.

1 The effects of guanethidine pretreatment on the release of [14C]-histamine during the reflex vasodilatation induced in the atropinized gracilis muscle by rapid intravenous administration of noradrenaline, were studied in dogs. 2 After guanethidine treatment the haemodynamic reflex response was completely abolished and no appreciable modification of [14C]-histamine release from the gracilis muscle following intravenous noradrenaline was observed. 3 These results suggest the hypothesis that the withdrawal of the sympathetic discharge represents the mechanism of histamine release during the reflex vasodilatation. Therefore, guanethidine would suppress both the passive and the histaminergic component of the baroreceptor reflex through the abolition of the sympathetic tone.

Animals↗
PubMed1977

Histamine mediation in muscular vasodilatation induced by beta adrenoceptor stimulation in dogs.

This study was designed to investigate the possibility of a histamine mediation in muscular vasodilation induced by beta adrenoceptor stimulation. Accordingly, in seven dogs the effects of isoproterenol administration on the release of 14C-histamine from the perfused gracilis muscle were studied. Beta adrenoceptors stimulation induced a vasodilatation, as shown by a decrease in perfusion pressure(-43 +/- 12 mm Hg); simultaneously, a significant increase of the radioactivity measured in the venous blood effluent from the gracilis muscle was observed. Both these events were blocked by propranolol. In the other five dogs, chlorpheniramine was able to reduce the vasodilatation induced by the injection in the gracilis muscle of isoproterenol. Under control conditions, isoproterenol induced a fall in perfusion pressure of 44 +/- 5 mm Hg while, after chlorpheniramine, perfusion pressure decreased by only 24 +/- 4 mm Hg. The results of this study seem to confirm the possibility of a histamine mediation in isoproterenol-induced vasodilatation. However, further investigation is needed in order to identify the exact role of histamine in the geneis of this phenomenon.

Animals↗
PubMedDate not supplied

Diltiazem in the treatment of mild or moderate essential hypertension. Comparison with metoprolol in a crossover double-blind trial.

The antihypertensive efficacy and tolerability of a calcium antagonist drug, diltiazem (60 mg q.i.d. per os), was compared with that of metoprolol (100 mg b.i.d. pr os) in a crossover, double-blind randomized trial in 20 patients with mild or moderate essential hypertension. Blood pressure and heart rate were assessed at rest and during bicycle exercise before and after four-week periods of treatment. Both metoprolol and diltiazem reduced significantly systolic and diastolic blood pressure, while heart rate decreased only after metoprolol therapy. The reduction in blood pressure and the percentage of patients who responded favorably were similar with the two drugs. Furthermore, the overall levels of blood pressure during exercise were significantly reduced by both treatments, while only metoprolol was able to reduce the maximum increase in systolic blood pressure and heart rate induced by exercise. These results suggest that the use of diltiazem may be appropriate to the treatment of patients with mild or moderate essential hypertension.

Adult↗
PubMedDate not supplied

Indenolol: a new antihypertensive agent: efficacy, toxicity, and hemodynamic effects in a crossover double-blind study with metoprolol.

The antihypertensive efficacy of a new agent, indenolol, was compared with that of the well-established antihypertensive drug, metoprolol, and its hemodynamic effects were investigated using echocardiography. Eighteen hypertensives completed a double-blind, crossover, randomized study using indenolol and metoprolol. Two four-week courses with indenolol or metoprolol were preceded and followed by a two-week placebo period; the total duration of the study was 14 weeks. Indenolol proved to be significantly more effective than metoprolol in decreasing blood pressure values at rest (P less than .05). Furthermore, three patients that failed with metoprolol were successfully treated with indenolol. Both drugs induced a significant decrease in cardiac output that was mediated mainly through a reduction in heart rate, because stroke volume, left ventricle circumferential fiber shortening velocity, and ejection fraction were not significantly reduced by either drug. However, after indenolol, a significant direct relationship was found between the basal values of both cardiac output (r = .809) and total peripheral resistance (r = .800), and the reduction of these parameters. On the contrary, after metoprolol only, the correlation between the basal value of cardiac output and its reduction was significant (r = .790).

Adolescent↗
PubMedDate not supplied

Inverted response of arginine vasopressin to postural change in patients with essential hypertension.

1. This study was designed to compare the response of plasma arginine vasopressin (AVP) to head-up tilt in hypertensive patients and in normals. 2. As expected, plasma AVP showed a consistent increase (P less than 0.005) in normal subjects after tilt while plasma volume decreased significantly (P less than 0.02). On the contrary, in hypertensive patients, after tilt both plasma AVP (P less than 0.025) and plasma volume (P less than 0.05) decreased. 3. These findings, thus, indicate that essential hypertension is characterized by an inverted response of arginine vasopressin to postural change.

Adolescent↗
PubMedDate not supplied

Early impairment of renal hemodynamic reserve in patients with asymptomatic heart failure is restored by angiotensin II antagonism.

BACKGROUND: The early/asymptomatic stages of heart failure (HF) are characterized by sodium retention secondary to derangement of sodium reabsorption at the proximal nephron level. Because this phenomenon is reversed by ACE inhibition, abnormalities of renal sodium handling may depend on intrarenal changes of angiotensin II (AII)/nitric oxide (NO) levels. Renal hemodynamic reserve (ie, the glomerular vasodilatory response to amino acid infusion) has been proposed as a reliable test to assess in vivo AII/NO balance. METHODS AND RESULTS: In this study, the effects of 6 weeks of treatment with 5 mg/d of enalapril or with 50 mg/d of losartan on systemic hemodynamics and renal function were assessed, at baseline and after amino acid infusion (AA), in patients with mild HF (NYHA class I) and in healthy volunteers. Untreated HF patients showed a basal renal function comparable to that of healthy subjects. After AA, glomerular filtration rate and renal plasma flow significantly increased in healthy subjects (+29.0% and +30.4%, respectively), whereas no vasodilatory response was observed in HF. Although they did not affect basal renal hemodynamics, both enalapril and losartan restored a normal response to AA in HF patients. Blood pressure and heart rate were comparable in HF subjects and healthy subjects at baseline and were not modified by either treatment. Left ventricular ejection fraction was depressed in HF but did not change after either drug. Urinary excretions of cGMP and nitrate (indexes of NO activity in the kidney), comparable in healthy subjects and in HF patients, were unchanged by either enalapril or losartan and did not correlate with renal reserve. CONCLUSIONS: (1) Renal functional reserve is absent in patients with early/asymptomatic HF and normal renal function and (2) both enalapril and losartan restore a normal vasodilatory response to AA in these patients without affecting basal systemic and renal hemodynamics. These data suggest a major role of AII in the development of early abnormalities in patients with HF.

Adult↗
PubMedDate not supplied

Studies of the mechanisms underlying impairment of beta-adrenoceptor-mediated effects in human hypertension.

To investigate the impairment of beta-adrenoceptor responsiveness in human hypertension, we evaluated the effect of an oral salt load (400 mEq/day of NaCl for 7 days) on plasma catecholamine concentrations and beta-adrenoceptor-mediated effects in 11 young patients with mild essential hypertension. Responses of heart rate and plasma cAMP to isoproterenol administration were used as indices of beta-adrenoceptor responsiveness. Salt loading induced a significant reduction in the dose of isoproterenol required to raise the heart rate by 25 bpm (CD25) (from 7.6 +/- 1.5 to 5.3 +/- 0.9 micrograms, p less than 0.05) and an increase in the slopes of the regression lines for heart rate changes and isoproterenol doses (delta HR/IS) (from 3.3 +/- 0.6 to 4.7 +/- 0.7, p less than 0.05) and for plasma cyclic AMP (cAMP) level changes and isoproterenol doses (delta cAMP/IS) (from 0.3 +/- 0.06 to 1.4 +/- 0.3, p less than 0.05). After salt loading there was a significant reduction in plasma catecholamine concentrations with a significant relationship between changes in upright plasma epinephrine levels and changes in CD25 (r = 0.904, p less than 0.01) and in the slopes for delta HR/IS (r = 0.983, p less than 0.001) and delta cAMP/IS (r = 0.922, p less than 0.001). These results support the hypothesis that the impairment of beta-adrenoceptor sensitivity observed in human hypertension is associated with a beta-adrenoceptor overstimulation due to chronically elevated adrenergic tone.

Adolescent↗
PubMedDate not supplied

Effect of atrial natriuretic factor on blood pressure, renin, and aldosterone in Goldblatt hypertension.

We previously provided evidence that atrial natriuretic factor (ANF) antagonizes angiotensin II-induced vascular contractility and angiotensin II-stimulated aldosterone production by isolated adrenal cells. To examine the importance of these effects in vivo, synthetic ANF (auriculin A) was administered intravenously (2 micrograms/kg bolus followed by 0.3 microgram/kg/min constant infusion) to conscious, unrestrained two-kidney, one-clip and one-kidney, one-clip rats on normal sodium intake and their sham-operated controls. The one-kidney, one-clip rats also were studied on a sodium-deficient diet. Mean blood pressure, plasma renin activity, and plasma aldosterone levels were measured before and after 60-minute infusion. In saralasin-responsive two-kidney, one-clip rats (n = 10), ANF administration reduced blood pressure (from 187 +/- 11 [SE] to 153 +/- 11 mm Hg; p less than 0.001) and plasma aldosterone levels (from 182 +/- 61 to 125 +/- 60 ng/dl; p less than 0.05), while plasma renin activity increased (from 59 +/- 16 to 82 +/- 20 ng/ml/hr; p less than 0.05). Lesser changes in blood pressure occurred in saralasin-nonresponsive two-kidney, one-clip rats (149 +/- 10 to 143 +/- 8 mm Hg; n = 5), sodium-replete one-kidney, one-clip rats (183 +/- 9 to 170 +/- 11 mm Hg; n = 9), two-kidney sham-operated rats (122 +/- 3 to 115 +/- 4 mm Hg; n = 8), and one-kidney sham-operated rats (117 +/- 3 to 112 +/- 3 mm Hg; n = 7). Control plasma renin and aldosterone levels were not elevated in these latter groups and did not change significantly with ANF administration. In sodium-depleted one-kidney, one-clip rats, which became saralasin responsive, ANF administration significantly reduced blood pressure (from 184 +/- 11 to 156 +/- 12 mm Hg; n = 8), plasma aldosterone levels (from 286 +/- 41 to 179 +/- 36 ng/dl), and plasma renin activity (from 69 +/- 19 to 44 +/- 13 ng/ml/hr).(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone↗
PubMedDate not supplied

[Assessment of the adequacy of health services in day hospital care: experience of an endocrine surgery day care unit at a university polyclinic].

The aim of the study was to assess the appropriateness of the provision of surgical treatment in the day hospital setting and at the same time to evaluate the efficacy of the service provided. The study was conducted on admissions to a day care unit operating in conjunction with the surgery division of a university hospital. The evaluation of appropriateness was carried out using explicit criteria, based on regional regulations and on guidelines drawn up by the Agency for Regional Health Services. The criteria related to the hospital bed equivalent Rotation Index and to the types of DRGs treated and services provided. Efficacy was assessed using the following para-meters: number of US-guided fine needle aspiration biopsies; techniques used; age, sex and nodule size; patient distribution by results of diagnostic examination; cytological classification; percentage of patients with complications. We also evaluated the possibility of transferring short-term (2-3 days) surgical admissions from ordinary regimens to the day care setting. The results of this study yield useful synthetic indicators for assessing the appropriateness both of the day care function as a whole and of individual operating units, providing both administrative and medical staff with a useful frame of reference for the planning of health-care management.

Adult↗
PubMedDate not supplied

[Hydatid choleperitoneum: a rare complication of hepatic hydatid disease].

The authors report their experience relative to hydatid choleperitoneum which is a rare complication of hydatid hepatic disease (one case of 236 operated). They underline how such pathology constitutes a clinic and anatomopathological case, well characterized and different from those offered by other complications of this hepatic disease. They draw attention moreover on how preoperative diagnosis is often difficult and consequently how the surgical therapeutic technique requires a very careful examination of anatomic relations of the lesion and recognize, as a chiefly foundation, a radical treatment of hepatic disease and whenever possible, the removal of the pseudomembrane of encystment.

Adult↗
PubMedDate not supplied

[The quality of medical records: a retrospective study in Lazio Region, Italy].

INTRODUCTION: Medical records have an important role in the communication among different care providers and in forensic medicine. In Italy, information on completeness and correctness of medical records is scanty, whereas future hospital accreditation could take into account their quality as a proxy of good medical practice. PURPOSE: We performed a retrospective study in order to assess the quality of medical records in the Lazio region. METHODS: From all 37009 hospital discharges for five different diseases in 123 hospitals (acute myocardial infarction (AMI), coronary artery bypass surgery, pneumonia, cerebrovascular disorders, breast surgery), registered in the Regional Hospital Information System, we selected a random sample of 2022 (5.5% of the total). Ten physicians, previously trained, reviewed the relative medical charts and filled in "ad hoc" questionnaires. RESULTS: A total of 1960 (97% of the target) charts were reviewed. Organization and structure of data recording strongly varied. Important differences were found across the diseases for various items: presence of anamnesis 98.1% (range: from 95.6% for breast surgery to 100% for AMI); presence of physical examination 92.7% (range: from 88.1% for breast surgery to 98.5% for AMI), completeness of the daily medical records was good in 70.8% (range: from 34.2% for pneumonia to 93.9% for cerebrovascular disorders). Variability among different type of hospitals was also observed, being teaching hospitals and some private hospitals more accurate. CONCLUSIONS: Quality of medical records tended to vary across different type of hospitals and different diseases. Actions for improving the quality should be undertaken as a priority. Efforts have to be done in restructuring charts, creating guidelines and training caregivers. The development and application of computer based health information systems should help solving these problems.

Hospitals↗
PubMedDate not supplied

[The discharge form: advantages and limits legionellosis cases individuation].

Despite legionellosis surveillance is active in Italy since many years, the disease notification appears still undervalued. A multicentric survey was carried out among 5 big Italian hospitals. It examined 11,435 discharge forms (1999-2001), reporting pneumonia diagnosis. Legionellosis (II class of notify system for infectious disease) was studied among pneumonia diagnosis by discharge forms. According to the ICD9-CM, there's no specific code for legionellosis (this disease is included among "others gram-negative pneumonia"). So the presumed pneumonia imputable to Legionella spp were the 2.7% of the whole number of analyzed discharge forms. Besides, the data regarding the other pneumonia showed that the etiological agent was specified only in the 11.2% of the case. This situation could be rectified both introducing adequate discharge forms codes and promoting the etiological diagnosis during the hospital stay.

Adolescent↗
PubMedDate not supplied

[Appropriateness evaluation of short hospital admissions using Appropriateness Evaluation Protocol (Italian version): experience of a teaching hospital].

Italian version of Appropriateness Evaluation Protocol (AEP) is a tool for evaluating the appropriateness of hospitalization for acute patients. In particular, it aims to verify and quantify the reasons of appropriateness associated to the day of admission and the single days of hospital stay. The aim of the present paper is to evaluate the appropriateness of ordinary, 2-3 days lasting, hospital admissions within an university hospital. We examined a sample of 518 hospital admissions: 370 admissions (71%) lasting 2 days, and 148 admissions (29%) lasting 3 days. Results analysis showed different levels of appropriateness between the 2-days and the 3-days admissions: the appropriate admissions were 18% in the sample of the 2-days admissions and 38% in the sample of 3-days admissions. Most inappropriate days of admission and stay in hospital are due to attended or to the execution of diagnostic procedures. In order to evaluate accuracy by means of AEP methodology, it is necessary to improve the quality of medical documentation using standardized medical records. AEP, in the framework of the continuous quality improvement, is a valid tool to reorganise health care processes.

Diagnosis-Related Groups↗
PubMedDate not supplied

[Evaluation of the appropriateness of hospital admissions using the iso-gravity classification systems APR-DRG and Disease Staging and the Italian version of Appropriateness Evaluation Protocol (AEP)].

Our main purpose was to evaluate the organizational appropriateness of admissions made in a university hospital, by comparing two iso-gravity classification systems, APR-DRG and Disease Staging, with the Italian version of AEP (PRUO). Our analysis focused on admissions made in 2001, related to specific Diagnosis Related Groups (DRGs), which, according an Italian Law, would be considered at high risk of inappropriateness, if treated as ordinary admissions. The results obtained by using the 2 classification systems did not show statistically significant differences with respect to the total number of admissions. On the other hand, some DRGs showed statistically significant differences due to different algorithms of attribution of the severity levels used by the two systems. For almost all of the DRGs studied, the AEP-based analysis of a sample of medical records showed an higher number of inappropriate admissions in comparison with the number expected by iso-gravity classification methods. The difference is possibly due to the percentage limits of tolerability fixed by the Law for each DRG. Therefore, the authors suggest an integrated use of the two methods to evaluate organizational appropriateness of hospital admissions.

Diagnosis-Related Groups↗
PubMedDate not supplied

[Diverticulosis of the small intestine. Observations on a complicated case].

Small bowel diverticula, particularly the jejunal ones, are a rare disease with a poor and vague symptomatology. Sometimes detected by change under X-ray examinations or at surgery, they do not need any surgical treatment: only clinical and X-ray controls are required. Prophylactic resection of symptomatic low jejunal diverticula is controversial: patient's age and status will affect the indication to surgical treatment. Jejunal diverticulosis may generate serious, though not dramatic, symptoms: intestinal obstruction, inflammatory complications, haemorrhage, perforation of the diverticula are the most frequent emergencies which require an immediate surgical procedure. A clinical case is here reported.

Aged↗