PubMed Health⌕ Search

Biomedical subjects

M M Lopes

Publications and source records attributed to M M Lopes.

8 recordsLinked to original sources
PubMed2000

Potential utility of random amplified polymorphic DNA (RAPD) and restriction endonuclease assay (REA) as typing systems for Madurella mycetomatis.

Two molecular methods were compared, random amplified polymorphic DNA (RAPD) and restriction endonuclease analysis (REA), in order to evaluate their ability to discriminate, and to characterize Madurella mycetomatis strains isolated from human mycetomas in different parts of the world. Both methods were able to cluster the Madurella mycetomatis isolates into the same number of distinct typing groups. However, RAPD, presenting several advantages over REA such as its rapidity, simplicity, and the accessibility for implementation in the laboratory, is a more sensitive and reproducible tool for the study of Madurella mycetomatis epidemiology than REA.

DNA Restriction Enzymes↗
PubMed1999

The effect of a re-wetting agent on dentin bonding.

OBJECTIVES: Recently, a new generation of simplified one-bottle dentin bonding systems, sensitive to variations in the degree of substrate moisture, was introduced. This in vitro project compared the dentin bond strengths and interfacial ultra-morphology formed by three one-bottle bonding systems [OptiBond SOLO (ethanol-based), Prime&Bond 2.1 (acetone-based), and Single Bond (ethanol- and water-based)]. The null hypothesis tested was that re-wetting a dried dentin surface with a HEMA aqueous solution would not result in bond strengths, and resin impregnation into demineralized dentin, comparable to those obtained for moist dentin. METHODS: Dentin specimens were assigned to the following three etched surface conditions: moist dentin-control group; dentin dried for 5 s; and dentin dried for 5 s and re-moistened with a commercial 35% HEMA aqueous solution. Mean shear bond strengths were calculated and analyzed with one- and two-way ANOVA. Dentin discs treated with the same combination of surface condition/adhesive were processed and observed under both transmission and scanning electron microscopes. RESULTS: For moist dentin, the morphology of the resin-dentin interfaces showed penetration of the dentin adhesives to the depth of the transition between demineralized and unaffected dentin. Drying dentin for 5 s resulted in a significant decrease in mean bond strengths and an incompletely infiltrated collagen structure with areas of unveiled collagen fibers, regardless of the solvent. Re-wetting dentin with the aqueous HEMA solution re-established the level of bond strengths obtained to moist dentin and resulted in a raise of the fiber network with simultaneous increase in interfibrillar space dimensions. SIGNIFICANCE: The results suggest that the use of an aqueous HEMA solution might compensate for the dryness induced on dentin surfaces by using air blasts from an air syringe, after rinsing off the etchant. As the behavior of the material that contained water was also affected by surface dryness, the percentage of water included in the composition of current ethanol- and water-based adhesives, such as Single Bond, may not be enough to compensate for the collapse of the collagen filigree upon drying.

Analysis of Variance↗
PubMed1991

[Assessment of the left ventricular function in patients with pacemakers VVI and DDD, using non-invasive methods (systolic time)].

OBJECTIVE: Determination of left ventricular function, in patients with ventricular inhibited (VVI) and atrioventricular universal (DDD) pacemakers, by measurement of systolic time intervals. DESIGN: Twenty six patients were studied (six with DDD pacemakers and twenty with VVI pacemakers). In all of them systolic time intervals measurements were obtained the day before and one week after the implant. PATIENTS: We have studied twenty six patients consecutively, and all of them completed the study. INTERVENTIONS: The measurement of systolic time intervals was obtained, by the simultaneous recording of ECG, phonocardiogram and carotid arterial pulse. The recordings were obtained at a paper speed of 100 mm/sec. MEASUREMENTS AND RESULTS: The values obtained before the implantation were similar in both groups, but one week after implantation they show a closer to normal ventricular function, in patients with DDD pacemakers. CONCLUSIONS: The measurements of systolic time intervals, is a very easy method, to determine left ventricular function non invasively. In patients with DDD pacemakers, the left ventricular function, was better than in patients with VVI pacemakers.

Aged↗
PubMed1989

[Alcohol and the heart].

Alcohol, above certain levels in blood, becomes a depressor of myocardial fiber. Excessive intake of alcoholic drinks is responsible for disrhythmias, congestive heart failure, thromboembolic phenomena and, sometimes, sudden death. Dilated cardiomyopathy is the usual clinical presentation of these patients. More than 60 gr daily of ethanol may be an important factor in the etiology of high blood pressure. Yet, not everything is negative as far as alcohol and heart are concerned. Moderate consumption of ethanol decrease the risk of coronary heart disease, but, regarding the medical and social implications of alcoholic habits, they shall not be encouraged. Finally, it must be emphasized that in cases of disrhythmias, hypertension and deteriorated left ventricular function (ejection fraction below 35%) the use of alcoholic beverages must strongly discouraged. The same applies to patients taking anticoagulants or sedative drugs.

Alcohol Drinking↗
PubMedDate not supplied

[Hypoglycaemia without ketosis. A case report].

INTRODUCTION: Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD) is a rare disease, inherited as autosomal-recessive trait, with variable clinical presentation including severe hypoglycaemia, cardiomyopathy, sudden infant death, progressive liver failure, 'Reye like' syndrome, neuromyopathy, muscle weakness and rhabdomyolysis. CASE REPORT: We report a 3 years old male patient admitted to our emergency department with vomiting, hypotonia and prostration, after a common respiratory infection. The presence of hypoketotic hypoglycaemia and elevated liver enzymes in the admission motivated a metabolic study. We found an abnormal low lactate/pyruvate ratio, decreased serum carnitine and dicarboxylic aciduria leading to the diagnosis of a fatty acid oxidation disorder (LCHADD). The molecular study of HADHA gene revealed homozygosity for the G1528C mutation in the patient DNA, and heterozygosity in both parents. CONCLUSIONS: The diagnosis of a fatty acid oxidation disorder must be considered in the presence of vomiting associated with excessive prostration specially if there is hypoketotic hypoglycaemia or familiar sudden infant death history. Physicians should be aware about these conditions and for the importance of measuring both glycaemia and ketone bodies during the evaluation of high risk situations.

3-Hydroxyacyl CoA Dehydrogenases↗