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Biomedical subjects

D D'Alessandro

Publications and source records attributed to D D'Alessandro.

At least 19 recordsLinked to original sources
PubMed1999

National Surveillance System and Hib meningitis incidence in Italy.

In 1994, the Italian Ministry of Health implemented a National Surveillance System to obtain data on the incidence of bacterial meningitis and its causative agents, including Haemophilus influenzae type b (Hib). As a consequence, case reporting of Hib meningitis is increasing year by year; in 1996, there were 126 notifications, of which 73% were in children under 2 years of age. Although underreporting still exists, parallel prospective or retrospective epidemiological surveys conducted in some Italian Regions allowed for partial correction of the incidence of Hib meningitis (up to 18.5/100,000 population in 1994).

Age Distribution↗
PubMed1997

Vasopressin deficiency contributes to the vasodilation of septic shock.

BACKGROUND: The hypotension of septic shock is due to systemic vasodilation. On the basis of a clinical observation, we investigated the possibility that a deficiency in vasopressin contributes to the vasodilation of septic shock. METHODS AND RESULTS: In 19 patients with vasodilatory septic shock (systolic arterial pressure [SAP] of 92 +/- 2 mm Hg [mean +/- SE], cardiac output [CO] of 6.8 +/- 0.7 L/min) who were receiving catecholamines, plasma vasopressin averaged 3.1 +/- 1.0 pg/mL. In 12 patients with cardiogenic shock (SAP, 99 +/- 7 mm Hg; CO, 3.5 +/- 0.9 L/min) who were also receiving catecholamines, it averaged 22.7 +/- 2.2 pg/mL (P < .001). A constant infusion of exogenous vasopressin to 2 patients with septic shock resulted in the expected plasma concentration, indicating that catabolism of vasopressin is not increased in this condition. Although vasopressin is a weak pressor in normal subjects, its administration at 0.04 U/min to 10 patients with septic shock who were receiving catecholamines increased arterial pressure (systolic/diastolic) from 92/52 to 146/66 mm Hg (P < .001/P < .05) due to peripheral vasoconstriction (systemic vascular resistance increased from 644 to 1187 dyne.s/cm5; P < .001). Furthermore, in 6 patients with septic shock who were receiving vasopressin as the sole pressor, vasopressin withdrawal resulted in hypotension (SAP, 83 +/- 3 mm Hg), and vasopressin administration at 0.01 U/min, which resulted in a plasma concentration (approximately 30 pg/mL) expected for the level of hypotension, increased SAP from 83 to 115 mm Hg (P < .01). CONCLUSIONS: Vasopressin plasma levels are inappropriately low in vasodilatory shock, most likely because of impaired baroreflex-mediated secretion. The deficiency in vasopressin contributes to the hypotension of vasodilatory septic shock.

Adult↗
PubMed1996

Development of an intraluminal device for the treatment of aortic regurgitation: prototype and in vitro testing system.

OBJECTIVES: Development of an intraluminal device to reduce aortic regurgitation could provide a strategy intermediate between medical treatment and aortic valve replacement. An initial prototype and a testing system have been designed. METHODS: Aortic valves obtained from heart transplant recipients were explanted and assessed in a mock circulatory loop with resistive and capacitive elements, including pressure-flow characteristics, similar to those of a normal arterial system. Normal heart function was simulated by a pulsatile ventricular-assist device. Pressure on each side of the valve and flow through the valve were recorded, allowing the calculation of regurgitant fractions and transvalvular gradients. Six solid geometrically differing obturators were tested. RESULTS: All six designs resulted in significant reduction in aortic regurgitation (p < 0.0001), ranging from 15% to 38% improvement compared with control values. Small increases in transvalvular gradients (from 0 to 7 mm Hg) were also noted. DISCUSSION: Initial results suggest that an intraluminally placed obturator can reduce aortic regurgitation without creating clinically significant transvalvular gradients. These initial in vitro experiments demonstrate the feasibility of an intraluminal device for the treatment of aortic valve disease, and further investigation is warranted.

Aortic Valve↗
PubMed1994

Attitudes and behavior of health care personnel regarding influenza vaccination.

This paper reports the results of a study conducted by the Italian Association for Immune-Prophylaxis Promotion (AIP.I) with the aim of surveying the attitudes and perceptions of Italian health care workers regarding the use and efficacy of influenza vaccine. The results clearly show that a high proportion of the questioned health care workers showed a general lack of concern about the severity of the disease. Doubts about vaccine efficacy and fear of post-vaccination side effects were also observed to have an important influence on the vaccination acceptance rates. These data underline the need for a systematic education program to provide influenza vaccination within the public and private health-care sectors in Italy.

Attitude of Health Personnel↗
PubMed1991

Prevalence survey of nosocomial infections in a paediatric hospital.

A prevalence survey of nosocomial and community infections in a children's hospital was carried out in the wards of the Bambino Gesù Hospital, Rome, Italy. The overall prevalence of hospital-acquired infection (HAI) was 5.1%, with higher rates in surgical units and among children aged 1 to 5 years. The proportion of community-acquired infections was 9.2%, with higher rates in the infectious disease and internal medicine units and among children aged 6 to 11 years. The most frequent type of HAI was respiratory tract infection, with only a small number of urinary tract infections.

Child↗
PubMed1985

Digestive tract endoluminal perfusion of cisapride (R 51619) and effects on gastrointestinal hormone levels in anaesthetized pigs.

The authors evaluated the in vivo effects of the new drug Cisapride on gastrointestinal hormone release in the mini-pig. Cisapride has been reported to stimulate and coordinate peristalsis of the GI tract. Selective endoluminal perfusion with Cisapride solution of the isolated but not denervated gastric antrum, duodenum and distal ileum demonstrated a significant increase of gastrin levels following perfusion of the gastric antrum and a decrease in vasoactive intestinal peptide following perfusion of the duodenum, only at very high doses.

Animals↗
PubMedDate not supplied

Clinical predictors of treatment reduction in hypertensive patients.

OBJECTIVE: To demonstrate that some hypertensive patients under good blood pressure (BP) control can reduce medications, and to identify predictors of successful reduction. DESIGN: Observational study with 11-month follow-up. SETTING: Outpatient hypertension clinic at the Seattle Veterans Administration Hospital. PATIENTS: 59 males (51% of those eligible) with diastolic BP less than 95 mm Hg for greater than or equal to 6 months; 57 patients (97%) completed the study. INTERVENTION: Gradual reduction of medications unless diastolic BP rose above 95 mm Hg. MEASUREMENTS AND MAIN RESULTS: Intensity of treatment with BP medications was assessed using a scale of their comparative "vigors." 35 patients (59%) reduced medications successfully. By the end of the study, systolic BP had risen by 8.2 +/- 12.3 mm Hg (mean +/- SD) in successful patients, while diastolic BP did not change significantly. Two predictors of treatment reduction were statistically significant in both univariate and multivariate analyses: successful patients had been treated more intensively (2.7 +/- 1.7 vs. 1.3 +/- 0.5 "vigor units," p = 0.0001), and they had been enrolled in the clinic longer (5.5 +/- 3.0 vs. 3.1 +/- 2.3 years, p = 0.003). Lower systolic BP, higher urinary sodium excretion, lower compliance, and younger age were significant predictors of treatment reduction on univariate analysis only. Age less than or equal to 65 years had the highest sensitivity (86%) for treatment reduction, while treatment with two or more "vigor units" had the highest specificity (79%) and likelihood ratio (3.3). CONCLUSIONS: Treatment reduction is feasible in many well-controlled hypertensives, though systolic BP rises. Patients with high intensity and long duration of treatment are most likely to reduce medications successfully.

Antihypertensive Agents↗