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E Merlo

Publications and source records attributed to E Merlo.

15 recordsLinked to original sources
PubMed2005

Reproducibility of surface EMG variables in isometric sub-maximal contractions of jaw elevator muscles.

The aims of this study were: (1) to develop and assess reproducibility of a new method for measuring masticatory force in the intercuspal position; (2) to test the reproducibility of surface EMG signal amplitude and spectral variables in constant force contractions of jaw elevator muscles and its dependency on inter-electrode distance. The study was performed on the masseter and temporalis anterior muscles of both sides of nine healthy volunteers. An intraoral compressive-force sensor was used to measure maximal voluntary contraction forces in the intercuspal position and to provide a visual feedback on sub-maximal forces to the subject. Three experimental sessions were performed in three days. In each session, three isometric contractions at 80% of the maximal force were sustained by the subjects for 30s. The intra-class correlation coefficient (ICC) of the maximal force measure was 71.9%. ICC of average rectified value and mean power spectral frequency of the EMG signal increased with inter-electrode distance, with values larger than 70% with 30 mm inter-electrode distance. It was concluded that surface EMG variables measured in isometric contractions of the jaw elevator muscles with the proposed force recording system show good reproducibility for clinical applications when a 30 mm inter-electrode distance is considered.

Adult↗
PubMed2005

Quantitative founder-effect analysis of French Canadian families identifies specific loci contributing to metabolic phenotypes of hypertension.

The Saguenay-Lac St-Jean population of Quebec is relatively isolated and has genealogical records dating to the 17th-century French founders. In 120 extended families with at least one sib pair affected with early-onset hypertension and/or dyslipidemia, we analyzed the genetic determinants of hypertension and related cardiovascular and metabolic conditions. Variance-components linkage analysis revealed 46 loci after 100,000 permutations. The most prominent clusters of overlapping quantitative-trait loci were on chromosomes 1 and 3, a finding supported by principal-components and bivariate analyses. These genetic determinants were further tested by classifying families by use of LOD score density analysis for each measured phenotype at every 5 cM. Our study showed the founder effect over several generations and classes of living individuals. This quantitative genealogical approach supports the notion of the ancestral causality of traits uniquely present and inherited in distinct family classes. With the founder effect, traits determined within population subsets are measurably and quantitatively transmitted through generational lineage, with a precise component contributing to phenotypic variance. These methods should accelerate the uncovering of causal haplotypes in complex diseases such as hypertension and metabolic syndrome.

Adolescent↗
PubMed2004

Muscle-fiber conduction velocity estimated from surface EMG signals during explosive dynamic contractions.

Muscle-fiber conduction velocity (CV) was estimated from surface electromyographic (EMG) signals during isometric contractions and during short (150-200 ms), explosive, dynamic exercises. Surface EMG signals were recorded with four linear adhesive arrays from the vastus lateralis and medialis muscles of 12 healthy subjects. Isometric contractions were at linearly increasing force from 0% to 100% of the maximum. The dynamic contractions consisted of explosive efforts of the lower limb on a sledge ergometer. For the explosive contractions, muscle-fiber CV was estimated in seven time-windows located along the ascending time interval of the force. There was a significant correlation between CV values during the isometric ramp and explosive contractions (R = 0.75). Moreover, CV estimates increased significantly from (mean +/- SD) 4.32 +/- 0.46 m/s to 4.97 +/- 0.45 m/s during the increasing-force explosive task. It was concluded that CV can be estimated reliably during dynamic tasks involving fast limb movements and that, in these contractions, it may provide important information on motor-unit control properties.

Adult↗
PubMed2002

The IkappaB kinase inhibitor sulfasalazine impairs long-term memory in the crab Chasmagnathus.

Evidence for the participation of Rel/NF-kappaB transcription factors in long-term memory has recently been reported in the context-signal learning paradigm of the crab Chasmagnathus, in which a high correlation between long-term memory formation and NF-kappaB activation was observed. Two components of the NF-kappaB pathway in the crab brain have now been identified by cross-immunoreactivity using mammalian antibodies for IkappaB-alpha and IkappaB kinase alpha. Furthermore, IkappaB kinase-like phosphotransferase activity, which was inhibited by the IkappaB kinase inhibitor sulfasalazine, was detected in brain extracts. We have evaluated the effect of sulfasalazine administration on long-term memory tested at 48 h. Amnesia was found when sulfasalazine was administered pre-training and 5 h after training but not at 0 or 24 h after training. Thus, two periods for sulfasalazine-induced amnesia were found in coincidence with the two phases of NF-kappaB activation previously described (immediately and 6 h after training). The cyclooxygenase inhibitor indomethacin did not induce amnesia when administered pre-training. Thus, the possibility that sulfasalazine induces amnesia by means of cyclooxygenase inhibition is unlikely to be tenable. In vivo sulfasalazine inhibition of basal NF-kappaB activity was found between 30 and 45 min after injection, as assessed by electrophoretic mobility shift assay. On the other hand, in vivo sulfasalazine administration 6 h after training inhibited the second phase of training-induced NF-kappaB activation, providing evidence that the sulfasalazine effect on memory is due to a direct effect of the drug on the NF-kappaB pathway. These results provide the first evidence that IkappaB kinase and NF-kappaB activation are necessary for memory formation.

Amnesia↗
PubMed1986

A double-blind trial of fentonium bromide in the treatment of incontinent unstable bladder.

The effects of fentonium were compared with those of placebo in a double-blind, cross-over trial involving 28 incontinent women with unstable bladder. Fentonium bromide proved significantly more effective in reducing urgency and urge incontinence (p less than 0.05), in reducing detrusor pressure rise during bladder filling (p less than 0.01) and in increasing bladder volume at first stimulus (p less than 0.05). Well tolerated, fentonium bromide proved useful in the treatment of unstable bladder.

Adult↗
PubMed1984

Invasive cervical cancer in young women.

Between 1970 and 1979, 103 women below 35 years of age with invasive cervical cancer were treated at the First Obstetrics and Gynaecology Clinic of the University of Milan. Nine patients were pregnant or less than 3 months postpartum. Estimated 10-year disease-free survival, determined by the life-table method, was 100% in stage IA (37 patients), 79% in stage IB (45 patients), 67% in stage II (15 patients), 0% in stages III (5 patients) and IV (1 patient). Prognosis was also strongly associated with lymph-node involvement, 10-year actuarial survival decreasing from 93% in lymph-node-negative to 44% in lymph-node-positive patients (P less than 0.001). The prognostic relevance of the clinical stage decreased after adjustment for lymph-node involvement, but the statistical significance of lymph-node involvement was unaffected when stage was allowed for. In the present series, the estimated 10-year disease-free survival was 80% in patients treated by radical hysterectomy compared with 62% in the group treated by total hysterectomy (stage IB to IV patients only); this difference, however, was not statistically significant when the data were adjusted for clinical stage (P = 0.10). None of the 20 patients with recurrent disease could be managed successfully.

Adenocarcinoma↗
PubMedDate not supplied

[The use of discriminant analysis in the classification of the alcohol intake in a general adult population].

Different studies have highlighted the efficacy of some laboratory parameters as markers of the abuse of alcohol in alcoholics populations. The intent of the present study has been to verify if the same variables are able to discriminate the intake of alcohol also in a general population. The survey has been carried out on 510 subjects (224 males and 286 females), between 20 and 70 years old, living in a rural area in the North of Italy. Statistically relevant differences have been found amongst mean values of mean globular volume (VGM), containing hemoglobin (MCH), gamma-glutamil transferase (GGT), HDL cholesterol (ColHDL), tryglycerides, apoproteins-A (APO-A), serum glutamic-ossalacetic transaminase (SGOT), leukocyte, lead blood level in subgroups of population stratified according to drinking habits (heavy, moderate and medium drinkers). The discriminant function analysis, applied using all the 18 parameters as continuous variables, allows the correct classification of 57.84% of the cases amongst moderate, medium and heavy drinkers. The most influent selected variables result lead blood level, GGT, hematocrit and MCH. If we leave out the lead blood level (not weighted as a routine) the percentage falls to 52.35%. The analysis carried out on "extreme" groups (moderate and heavy drinkers) identifies as most influent the lead blood level, GGT, APO-A, and VGM variables, allowing the correct classification of 90.14% of the cases (83.39% excluding the lead blood level, selecting GGT, hematocrit, VGM and serum glutammic-piruvic transaminase. The casual reselection of samples confirms the obtained data, giving evidence of the independence of the used variables from particular characteristics of the sampled population.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗