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Roberto Manfredini

Publications and source records attributed to Roberto Manfredini.

43 records · Page 3Linked to original sources
PubMed2002

Patient demographic and clinical features and circadian variation in onset of ischemic stroke.

BACKGROUND: Studies have reported circadian variation in the onset of ischemic stroke, which may carry important pathophysiological implications. However, there is no detailed information about circadian variations among the subtypes of stroke. OBJECTIVE: To determine whether subgroups of patients with ischemic stroke with specific clinical characteristics would exhibit different circadian patterns, to more systematically examine the role of possible triggering or precipitating factors. DESIGN AND SETTING: Analysis of the effects of demographic, medical, and pathophysiological factors on the circadian pattern of an unselected series of patients with ischemic stroke consecutively admitted to our hospital. RESULTS: The study included 1656 patients. As in other studies, the peak of stroke onset occurred in the morning, with a second peak in the evening. Circadian variation in ischemic stroke onset was shown to be independent of clinical variables considered. CONCLUSIONS: Our study confirms the circadian rhythm of stroke reported in previous studies. There is a chronological pattern of ischemic stroke in the morning, which appears to be independent of the presence of risk factors and of clinical stroke subtypes. The role of circadian variability of blood pressure (present in patients with and without hypertension) and a concurrent morning hypercoagulability are suggested as possible determinants of this pattern. Preventive pharmacological interventions aimed at specifically targeting the morning rise in risk factors could be advantageous in reducing the overall risk of ischemic stroke.

Aged↗
PubMed2002

Circadian pattern of emergency calls: implications for ED organization.

A circadian variation has been shown in the onset of acute medical diseases and we postulate that there is a circadian variation in emergency calls. We reviewed the 20,858 emergency calls addressed to the Emergency Coordinating Unit of the Hospital of Ferrara, Italy, from January 1 to December 31, 1998. Precise determination of the time of calls was available from the recordings. Total calls and subgroups by different diseases were categorized into 24 one-hour increments and analyzed for circadian rhythmicity by applying a partial Fourier series. A circadian variation was found for all subgroups, except for alcoholic intoxication. There was a peak frequency of calls in the morning hours for cardiologic, respiratory, and neurologic disease. There was a peak frequency of calls in the afternoon for trauma, neoplastic diseases, and acute poisoning. Organization of quantity and quality of Emergency Department (ED) staff should take into account the increased demand of specific facilities during certain hours of the day.

Circadian Rhythm↗
PubMed2002

Morning preference in onset of symptomatic third-degree atrioventricular heart block.

The aim of this study was to examine 24h patterning in the symptoms indicative of third-degree atrio-ventricular (AV) heart block. We found a total of 227 cases (126 men and 101 women) of third-degree AV block that had been diagnosed by the Emergency Medical Department of the St. Anna Hospital in Ferrara, Italy between 1990 and 2001. Determination of the hour of onset of symptomatic third-degree AV block, however, was possible and listed in the records of only 161 or 70.9% of the cases (92 men and 69 women). The onset time of every event was categorized into one of four 6h spans of the 24h: night (00:00-05:59h), morning (06:00-11:59h), afternoon (12:00-17:59h), and evening (18:00-23:59h). The onset of the symptoms of third-degree AV block in the sample of 161 cases was significantly greater in the morning between 06:00 and 11:59h than any other 6h span of the day and night (chi2-test; p < 0.001). The same phenomenon was substantiated in the subgroup of the 92 males (chi2; p < 0.0001), although it could not be detected for the smaller subgroup of 69 women. The 24h pattern, with morning preference, in the onset of symptomatic third-degree AV block is similar to the one in sudden cardiac death and cardiogenic cardiac arrest. The etiology of the 24h pattern in symptomatic AV block is unknown; it may be an expression of intrinsic biological rhythmicity within the heart tissue or its control system, and/or the timing of environmental triggers resulting in coronary ischemia.

Aged↗
PubMed2002

Effects of doxazosin and propranolol on A2A adenosine receptors in essential hypertension.

A2A adenosine receptors inhibit neutrophil adhesion and superoxide anion generation. The aim of the present study was to evaluate the effect of antihypertensive treatment with doxazosin or propranolol on the binding and functional parameters of A2A adenosine receptors of lymphocytes and neutrophils in essential hypertensive patients. Two groups of previously untreated, essential hypertensive patients were studied. The mean affinity (K(d)) and density (B(max)) of adenosine receptors, by the A2A selective radioligand [3H]-ZM-241385 binding assays, and EC50, by cAMP assays, were obtained first on no medication and a second time after treatment for up to 13 weeks with doxazosin (13 patients) or propranolol (8 patients). A third group of 15 healthy normotensive volunteers matched by age, sex, and body mass index was used as a control. Binding and functional parameters of the A2A adenosine receptors were significantly higher in the 2 hypertensive groups than in controls (P always <0.0001), both in lymphocyte and neutrophil membranes. After treatment with propranolol, the binding parameters did not change significantly, whereas after treatment with doxazosin, K(d), B(max), and EC50 values returned to control levels. In never-treated essential hypertensive patients, lower affinity, higher density, and impaired function of A2A adenosine receptors are present. The binding and functional parameters of A2A adenosine receptors appear to be normalized after treatment with doxazosin but not with propranolol.

Adenosine-5'-(N-ethylcarboxamide)↗
PubMed2002

An incremental test to identify the pain threshold speed in patients with intermittent claudication.

The purpose of this study was to develop a test for identifying the speed of onset of claudication, or pain threshold speed (PTS), in 16 patients affected by intermittent claudication. An echo-Doppler examination and the ankle-brachial index (ABI) determination were also performed. Test repeatability was evaluated in 10 patients retested within a few days. All 16 patients underwent the incremental walking test 3 times during a 6-month rehabilitation training program to verify the test's sensitivity in detecting the expected functional modifications. PTS was identified in all patients examined and the test-retest correlation coefficient (R) for PTS was 0.98. During the 6-month rehabilitation period, the ABI rose from 0.43 +/-0.16 to 0.72+/-0.15 for the worst limb and PTS also rose significantly from 3.9+/-1.4 km/h to 6.1+/-1.1 km/h. The average increments of ABI and PTS were significantly correlated. An incremental walking test for the identification of the walking speed at which claudication occurs has been developed. The PTS is a reproducible parameter that can be combined with other test results to establish the severity of the disease and to check any modifications that occur during rehabilitation.

Adult↗
PubMedDate not supplied

Circadian and seasonal variation of migraine attacks in children.

OBJECT: To investigate the rhythmicity of migraine episodes without aura in a pediatric population. METHODS: Time of occurrence of 2517 migraine attacks in 115 children was recorded, by means of a diary, both by hourly and monthly intervals. RESULTS: A significant circadian variation, characterized by a peak in the afternoon (P < .001) and one in the early morning (P= .002) was found. A seasonal peak was also observed between November and January, while a nadir was observed in July. CONCLUSIONS: The clustering of attacks in the morning and midday and in autumn-winter, with a minimum frequency in July, suggests that school activities may represent an important cause of migraine.

Adolescent↗