PubMed Health⌕ Search

Biomedical subjects

N Locuratolo

Publications and source records attributed to N Locuratolo.

27 records · Page 2Linked to original sources
PubMed1989

[Abnormal coronary vasomotility in subjects with normal coronary arteries and reduced reserve of coronary flow].

A reduced coronary flow reserve has been reported in patients with ischemia-like symptoms and normal coronary arteries. In 13 such subjects both coronary vasomotion and flow reserve were studied. The luminal area of the proximal and distal third of the left anterior descending and left circumflex artery were determined by biplane quantitative coronary arteriography using a computer-assisted system. Subjects were studied at rest, during submaximal supine bicycle exercise (4.0 min, 116 W) and 5 min after sublingual administration of 1.6 mg nitroglycerin. Heart rate, mean pulmonary and aortic pressure as well as the percent change of both proximal and distal luminal area were determined. In 10 of the 13 subjects, coronary sinus blood flow was measured by coronary sinus thermodilution technique at rest and after dipyridamole infusion (0.5 mg/Kg in 15 min) 10 +/- 5 days after quantitative coronary arteriography. Coronary flow ratio (dipyridamole/rest) and coronary resistance ratio (rest/dipyridamole) were determined in these subjects. Subjects were divided into 2 groups according to the behaviour of the coronary vessels during exercise (vasodilation = Group 1, vasoconstriction = Group 2). Coronary vasodilation of the proximal (luminal area + 26%; p less than 0.001) and distal (+ 45%; p less than 0.001) artery was observed in 7 subjects (Group 1) during exercise and after sublingual nitroglycerin (+46%; p less than 0.001 and +99%; p less than 0.001, respectively). In Group 2 (n = 6), however, there was coronary vasoconstriction of the distal vessel segments (-24%; p less than 0.001) during exercise, whereas the proximal coronary artery showed vasodilation (+ 26%; p less than 0.001) during exercise. Following sublingual nitroglycerin, both vessel segments elicited vasodilation (distal coronary + 44%; p less than 0.001, proximal coronary artery +47%; p less than 0.001). Coronary flow ratio amounted to 2.5 in Group 1 and to 1.2 in Group 2 (p less than 0.05) and coronary resistance ratio to 2.7 in Group 1 and to 1.2 in Group 2 (p less than 0.05), respectively. Thus, among subjects with ischemia-like symptoms and normal coronary arteries there is a subgroup of patients (Group 2) with an abnormal dilator response of the distal coronary arteries to the physiologic dilator stimulus of exercise and a reduced dilator capacity of the resistance vessels after dipyridamole (= abnormal coronary vasodilator syndrome). The nature of this exercise-induced distal coronary vasoconstriction is not clear but might be due to an abnormal neurohumoral tone which may cause or contribute to the blunted vascular response during exercise.

Adult↗
PubMed1988

Electroencephalography and visually evoked potentials during moderate hypoglycemia.

The effects of hypoglycemia per se on the electroencephalogram (EEG) and visually evoked potentials (VEPs) were studied in eight normal young adults. The EEG and VEPs were recorded before and during hypoglycemic clamp studies, carried out at plasma insulin and glucose concentrations of about 287 pmol/L and 2.38 mmol/L, respectively. From the mean power EEG spectra obtained during each testing condition, several parameters in each frequency band considered were compared statistically. During the eyes closed recording, the mean frequency of the alpha-band (8-13 Hz) decreased from 10.1 +/- 0.2 (+/- SE) Hz in both the right and left frontal leads during euglycemia to 8.8 +/- 0.2 and 8.8 +/- 0.1 Hz (left and right frontal leads, respectively; P less than 0.05) during hypoglycemia. In the same leads, the peak frequency decreased from 10.6 +/- 0.4 and 10.3 +/- 0.4 Hz to 9.6 +/- 0.4 and 9.5 +/- 0.3 Hz, respectively (P less than 0.05). A similar pattern of variation was found during the eyes open recording. In contrast, mean VEP latencies did not vary significantly; they were 118 +/- 3 ms (smallest image size; square wave signals subtending 30 min of arc) and 116 +/- 3 ms (largest image size; square wave signals subtending 60 min of arc) during euglycemia to 121 +/- 3 and 119 +/- 3 ms, respectively, during hypoglycemia. This study demonstrates that the earliest hypoglycemia-induced EEG alterations occur in the frontal regions and can be quantified in terms of decreased mean and peak frequencies of the alpha-band. VEP latency is less sensitive. If confirmed in diabetic patients, these data may provide a theoretical basis for developing a portable device to detect early hypoglycemia in those patients who lack warning symptoms.

Adult↗
PubMedDate not supplied

The circulating insulin-like growth factor system in children with coeliac disease: an additional marker for disease activity.

BACKGROUND: Chronic undernutrition resulting from coeliac disease (CD) could be associated with changes in the circulating insulin-like growth factor (IGF) system, which may participate in the pathogenesis of growth retardation occurring in these patients. METHODS: We performed a cross-sectional study in CD subjects attempting to (1) document the pattern of serum IGF-I and IGF binding protein (IGFBP) 1 and 3 at diagnosis and (2) assess the response of circulating IGF system to dietary treatments, in comparison with the response of clinical and laboratory findings utilized for the diagnosis of CD. Thirty-two prepubertal CD children were divided into three groups based on the dietetic treatment: at diagnosis (D, n=18); on gluten-free diet for at least 6 months (GFD, n=7); and on gluten challenge for at least 3 months (CH, n=7). Six postpubertal CD patients were also studied at diagnosis. RESULTS: In prepubertal children IGF-I levels were significantly reduced (by 29%) in D vs sex- and age-matched normal control (NC) subjects, with reductions being more pronounced before 3 years of age. Likewise, serum IGFBP-3 concentrations were decreased by 22%, whereas circulating IGFBP-1 levels were increased by 60%, compared with NC, with more marked IGFBP changes in older children. Similar alterations were observed in postpubertal patients. Changes in the circulating IGF system disappeared in GFD subjects and reappeared in CH children, as positivity of disease-specific antibodies. Body mass index (BMI) also improved in GFD subjects, but did not decrease in CH children. Changes in IGF-I and IGFBPs did not correlate with each other. Levels of IGF-I, but not of IGFBPs, maintained the relation with age and correlated significantly with BMI and positivity of antibodies. CONCLUSIONS: These results demonstrate that CD patients show significant changes in serum IGF-I, in younger children, and IGFBPs (particularly IGFBP-1), in older children and adolescents, correlating with clinical course and response to dietary treatments. The alteration in the circulating IGF system could be implicated in the pathogenesis of growth retardation occurring in CD and may provide an additional tool in monitoring of the disease.

Autoantibodies↗