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Biomedical subjects

M Prencipe

Publications and source records attributed to M Prencipe.

At least 37 records · Page 2Linked to original sources
PubMed1994

Clinical study to assess the stain removal efficacy of two tartar control dentifrices and a low abrasive dentifrice.

Significant differences in stain removal have been demonstrated in a laboratory study comparing two tartar control dentifrices: Platinum, containing 1.3% soluble pyrophosphate and 1.5% of a copolymer, and Crest Tartar Control, containing 5% soluble pyrophosphate. The purpose of this clinical study was to evaluate the same tartar control dentifrices, and a low abrasive dentifrice for their ability to reduce Peridex-induced stain. Eighty-five subjects were given Peridex (0.12% chlorhexidine digluconate) and a low abrasive dentifrice for 4 weeks. The 76 subjects with sufficient stain were stratified using the Lobene index on buccal and lingual surfaces of anterior teeth, and randomly assigned one of the three dentifrices for 8 weeks. At the end of the study, total stain evaluations were significantly lower in the Platinum dentifrice group (mean 0.84) compared to both Crest Tartar Control dentifrice (1.08) and the low abrasive dentifrice (1.09) at p<0.05 by ANOVA. In this 8-week clinical study, Platinum dentifrice was significantly more effective than Crest Tartar Control dentifrice or a low abrasive dentifrice in reducing Peridex-induced stain, and this finding correlates well with laboratory data on removal of tea and coffee stain.

Adult↗
PubMed1993

Platelet changes in classic migraine.

We investigated some ultrastructural aspects of platelet activity in patients with classic migraine during an attack-free period. We focused on the production of malondialdehyde (MDA), the intracellular concentration of Ca++ and the membrane phospholipid structure using a DPH (1,6 diphenyl-1,3,5 hexatriene) fluorescent probe. Our study comprised 20 patients with classic migraine and 5 healthy controls, from whom 10 cc samples of blood were collected in test tubes containing sodium citrate (1/9 cc). We found no significant differences in MDA production between migraineurs and controls either before or after stimulation with thrombin. The same applies to the concentration of intracellular Ca++ (Ca++i). The membrane lipid composition assessed by DPH fluorescent probe was normal both in migraineurs and in controls. Our findings suggest no intrinsic activation of platelet aggregation.

Adolescent↗
PubMed1993

Transcranial Doppler evaluation of cerebral blood flow in patients with paroxysmal atrial fibrillation.

Cerebral blood flow was measured by transcranial Doppler sonography (TCD) in 15 patients during and after an attack of paroxysmal atrial fibrillation. During the attack the mean flow velocity (MFV) was reduced significantly in the middle cerebral artery (p < 0.05) and nonsignificantly in the other arteries. The pulsatility index (PI) was reduced in all the arteries but not significantly. During the fibrillation phase the MFV and PI tended to decrease as the heart rate increased. None of the patients showed clinical signs of cerebral ischemia during the attacks. The absence of such signs despite the reduced cerebral blood flow in atrial fibrillation is probably due to the activation of mechanisms of autoregulation.

Atrial Fibrillation↗
PubMed1993

Focal cerebral ischemia in young adults: a collaborative case-control study. The National Research Council Study Group.

Because there is uncertainty about the role of atherogenic and nonatherogenic risk factors for cerebral ischemia in the young, we carried out a multicenter, hospital-based, case-control study. 333 patients (15-44 years) with focal cerebral ischemia (transient ischemic attack or stroke within 8 weeks of admission) were eligible. 25 patients were excluded, according to the protocol. 308 cases were matched by age and gender to one hospital and one population control. Independent risk was shown by logistic conditional regression for migraine with aura [odds ratio (OR) = 14.8], smoking (OR = 3.7), alcohol (OR = 2.8), serum triglycerides (OR = 1.6), arrhythmias (OR = 9.5), mitral stenosis (OR = 56), coronary heart disease (OR = 4.3) and carotid stenosis or occlusion (OR = 41). Serum HDL-cholesterol had a relative protective effect (OR = 0.8). These data confirm the role of atherosclerosis and cardiac diseases as well as migraine with aura and alcohol consumption in the pathophysiology of cerebral ischemia in the young. More thorough prevention programs may contribute to earlier detection and control of all of these risk factors, but further investigations in patients with as yet unidentified risk factors are warranted because the above-mentioned factors do not account for the total risk of ischemic stroke in the young.

Adolescent↗
PubMed1993

A prospective study of cerebral ischemia in the young. Analysis of pathogenic determinants. The National Research Council Study Group.

BACKGROUND AND PURPOSE: The etiology of stroke in the young is different from that in older patients and remains unknown in almost one third of the cases. To gain further insight into both pathogenic and etiologic determinants, we prospectively studied a large number of consecutive young adults with focal cerebral ischemia. METHODS: Three hundred thirty-three patients aged 15-44 years with transient ischemic attack or ischemic stroke within the 8 weeks before hospital admission were recruited and investigated by using a standardized protocol of clinical evaluation, blood tests, electrocardiography, echocardiography, chest roentgenography, and brain computed tomography. Presumed etiology was diagnosed by prospectively applied criteria. RESULTS: Women predominated (61%) among patients under 35 years of age, mainly due to the frequency of cerebral ischemia related to oral contraceptive use, while men outnumbered women (60%) among patients over that age because of a higher prevalence of atherothrombotic disease. Potential cerebral embolism of cardiac origin was the presumed cause of stroke in 23.7%, but conventional sources of emboli were found only in 7.5% of cases. There was a low prevalence of atrial fibrillation among young patients with cerebral ischemia. Mitral valve prolapse was found in 8.4%, as expected, predominantly (71.4%) among the younger patients. The prevalence of stroke over transient ischemic attack was proportional to the likelihood of cardiac embolism. Acute alcohol intoxication was considered a precipitating factor in only three patients. The percentages of cerebral ischemia attributed to arterial dissection (0.3%), oral contraceptive use in women (8.1%), migraine (1.2%), and other associated medical diseases (1.5%) were lower than reported in recent clinical series. CONCLUSIONS: Two different groups of pathogenic determinants predominate in younger women and in older men, supporting public health measures aimed at strict medical control of the recognized cerebrovascular risk factors.

Adolescent↗
PubMed1992

Reproducibility of transcranial Dopplersonography: a validation study.

Transcranial Doppler-sonography (TCD) is a useful noninvasive technique for the measurement of intracranial arterial blood flow velocity. The present study evaluated the reproducibility of this method for repeated measurements of flow velocity in the anterior, middle and posterior cerebral, and basilar arteries. Thirty-six patients (23 males and 13 females) were studied. Three measurements were made by the same examiner on each patient with a time interval of 1 h between the first and the second examination, and about 24 h between the first and the third examination. The statistical evaluation for the reproducibility was performed by calculating the correlation coefficient (r). The results showed good reproducibility of TCD for all arteries both between the first and second and between the first and third measurements (r = 0.78-0.97; p less than 0.001), but when the middle cerebral artery mean velocity is low the posterior cerebral artery reproducibility is poorest (r = 0.42-0.54).

Blood Flow Velocity↗
PubMed1992

Cerebral blood flow in migraine with aura: a transcranial Doppler sonography study.

Transcranial Doppler sonography examination was performed on 44 patients with migraine with aura and 88 controls. All patients were investigated in headache-free periods and 10 of them also during a migraine attack. During the headache-free period a not significant increase of mean flow velocity in patients compared to controls was obtained. The pulsatility index (PI) mean values were also higher in patients than in controls and the differences were significant in the MCA (p < 0.05). No difference between right and left side was observed. During the attack the mean flow velocity (MFV) decreased in all arteries but the decrease was significant only in MCA and ACA (p < 0.05). The mean PI increased in all arteries but not significantly. These variations were observed both on the headache and contralateral side. Nevertheless, the MFV decrease in all arteries was observed in four patients only. In four patients the MFV decrease was found in the anterior arteries and the MFV increase in the posterior arteries, while in two patients the MFV increase was observed both in the anterior and posterior arteries. The correlation between the variations of MFV values during the attacks and the time interval from the onset of attacks showed that the PCA and BA flow velocities were increased in patients examined between 0.5 and 3 hours, while an increase in MCA and ACA flow velocities were observed only in patients examined after 1.5 hours.

Adult↗
PubMed1990

Nonrandom chromosome changes in multiple sclerosis.

In order to study the role of genetic factors in multiple sclerosis, cytogenetic analysis was performed on 48 patients with the clinically defined disease. We found a high incidence of subjects (50%) with abnormal chromosomes, showing premature centromere division of the X chromosome and structural aberrations, translocations, or deletions that could suggest preferential breakpoints. Correlation between clinical and cytogenetic data showed that cytogenetic abnormalities were more common in patients with high frequency of relapse or with a progressive form of the disease.

Adolescent↗
PubMed1990

Cyclophosphamide in relapsing remitting multiple sclerosis.

7 patients with relapsing-remitting multiple sclerosis (MS) were subjected to an intensive course of intravenous (I.V.) cyclophosphamide (CY) therapy. All patients received induction therapy with 11 daily doses of 300 mg/m2 and then a single dose every six months for three years. After one year of follow-up all patients showed a decrease in relapse rate (0.57.57); in the two subsequent years of follow-up 2 patients showed a mild worsening while the others were clinically stable. As suggested by others, our results indicate that I.V. CY therapy may influence the clinical course of relapsing-remitting MS.

Adolescent↗
PubMed1990

[Changes in headache with age: symptomology and clinical features].

The clinical features of 76 patients 5 to 14 years old suffering from primary headaches has been compared with those of 495 adults in the same diagnostic group. An association between migraine without aura and female sex was evident in both age groups, while an inversion of the usual M/F ratio was found in the younger group with other types of headache. Childhood headache attacks resulted to be less frequent, less severe and with a shorter duration than in adult patients. Also accompanying symptoms were less common in children than in adults. Furthermore pain was more often unilateral but less frequently pulsating in the younger group. These results point out the need for a different approach to childhood headaches.

Adolescent↗
PubMed1989

Leuko-araiosis: definition and clinical correlates--an overview.

Leuko-araiosis (LA) is a descriptive term coined by Hachinsky et al. to indicate bilateral and nearly symmetrical areas of decreased density of the periventricular white matter and centra semiovalia seen on CT or MRI scan. These findings are frequently observed in elderly people, but they seem to be more frequent or more severe in demented patients regardless of the etiology. Neurological abnormalities observed in patients with LA are nonspecific and insufficient to describe a definite clinical picture. The hypothesis that LA could be vascular in origin, even in Alzheimer patients is attractive but unproven.

Brain↗
PubMed1988

A prevalence study of multiple sclerosis in L'Aquila, central Italy.

We report the results of an epidemiologic study in the Municipality of L'Aquila, Abruzzo, Central Italy, undertaken to estimate the prevalence rate of Multiple Sclerosis (MS). On December 31, 1984, the prevalence was 33.2 per 100,000 (34.2 when age and sex is standardized to the Italian population). In agreement with recent intensive surveys from different regions in the North and South of Italy, our data indicate that the prevalence of MS in Italy is higher than 30 per 100,000, and emphasize the importance of small population studies in the epidemiology of MS. Our findings suggest that in Italy the risk for MS is higher than recorded before.

Adult↗
PubMed1986

Three-year neuropsychological follow-up of patients with reversible ischemic attacks.

A short neuropsychological test battery designed to measure language, memory and visuospatial abilities was administered to 217 patients with reversible ischemic attacks. Patients were tested twice: the first time more than one month, but less than one year, from the last ischemic episode, and the second time three years later. A comparison between the first and the second testing session did not disclose any significant worsening. The degree of atherosclerosis and the occurrence of further ischemic episodes during the follow-up period were found to be unrelated to change in performance at the test battery. These results seems to challenge the hypothesis that multi-infarct dementia may follow apparently reversible, or even clinically silent, ischemic episodes.

Follow-Up Studies↗
PubMed1986

T-lymphocyte subsets modifications in multiple sclerosis: correlation with clinical disease activity.

Serial analyses of peripheral blood T-lymphocyte subsets were performed in 280 samples collected over a 27 months period from 14 multiple sclerosis patients. A significant decrease of T8+ cells was found in 47.1% (47/87) of blood samples collected within four weeks of onset of a relapse opposed to 2.1% (1/47) of samples collected during the four weeks before a relapse and to 3.4% (5/146) of those collected over four weeks after a relapse. Changes of T-cells subsets appear to correlate with disease activity, but normal findings observed before relapses suggest that the decrease of T8+ cells cannot be used as valid predictor of relapse.

Antigens, Differentiation, T-Lymphocyte↗