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Biomedical subjects

F Moraes

Publications and source records attributed to F Moraes.

15 recordsLinked to original sources
PubMed2006

Lensing effects in a nematic liquid crystal with topological defects.

Light traveling through a liquid crystal with disclinations perceives a geometrical background which causes lensing effects similar to the ones predicted for cosmic objects like global monopoles and cosmic strings. In this paper we explore the effective geometry as perceived by light in such media. The comparison between both systems suggests that experiments can be done in the laboratory to simulate optical properties, like gravitational lensing, of cosmic objects.

Biotechnology↗
PubMed2006

Vitamin-mineral supplement use by low-income Brazilian pregnant adolescents and non-adolescents and the predictors for non-use.

OBJECTIVES: To determine (1) the intake of vitamin-mineral supplements by 855 low-income Brazilian pregnant adolescents and non-adolescents in three interviews (gestational ages < or =16, 20-26 and 30-36 weeks), (2) the relationship between vitamin-mineral supplementation and toxic exposure, and nutritional, psychological, socio-economic, demographic and obstetric characteristics of the women. DESIGN: Longitudinal cohort study. SETTING: Jundiaí city, São Paulo, Brazil. SUBJECTS: A total of 855 pregnant adolescents and non-adolescents who attended antenatal care from September 1997 to August 2000. METHODS: A general questionnaire was utilized three times in pregnancy (gestational ages < or =16, 20-26 and 30-36 weeks) to investigate the vitamin-mineral supplements ingested by the women, their smoking habit and alcohol intake, anthropometric measurements (pre-pregnancy and actual weight, height, mid-upper arm circumference) and psychological (anxiety, stress and distress), socio-economic (per capita income), demographic (education, age, marital status) and obstetric (gravidity) characteristics. The associations between vitamin-mineral supplementation and maternal characteristics were assessed in 12 multiple logistic regression models, stratifying the women by age and per capita income. RESULTS: Iron and vitamin C were the most ingested supplements by adolescents and non-adolescents, in the three interviews. Logistic regression analysis revealed that the maternal predictors for non-use of vitamin-mineral supplementation were acute anxiety and alcohol intake for adolescents, and low education, single without partner, distress (anxiety, depression, etc.) and stress for non-adolescents. CONCLUSIONS: These are important data to identify groups of low-income pregnant women in need of supplementation guidance and nutrition education. Stress/distress was a predictor for non-use of vitamin-mineral supplements for both adolescents and non-adolescents pregnant women.

Adolescent↗
PubMed2004

The relationship between salivary cortisol concentrations and anxiety in adolescent and non-adolescent pregnant women.

The main purpose of the present study was to determine the relationship between salivary cortisol concentrations and self-report anxiety in 50 adolescent and 178 non-adolescent women during the last month of pregnancy. The subjects were randomly selected from a previous study involving women who attended antenatal care from September 1997 to August 2000 at 17 health services in Southeast Brazil. Salivary cortisol was measured with an enzyme immunoassay kit, and anxiety was assessed by the State-Trait Anxiety Inventories (STAI) of Spielberger. After saliva collection, the participants completed the STAI. Mean concentrations of cortisol for both pregnant adolescents (14.17 +/- 6.78 nmol/l) and non-adolescents (13.81 +/- 8.51 nmol/l) were similar (P = 0.89). Forty-three percent of the pregnant adolescents and 30.5% of the non-adolescents felt anxious at the time of being questioned (State Anxiety Inventory (SAI) scores >40; P = 0.06). Cortisol concentrations in adolescents were negatively related to the SAI scores (r = -0.39; P = 0.01) which assess a temporary condition of anxiety. There was a statistically significant difference in mean cortisol concentrations between adolescents with low (<=40) and high (>40) SAI scores (P = 0.03, t-test), but no differences for non-adolescents. The negative relationship between salivary cortisol concentrations and anxiety scores in adolescents may be due to puberty-related hormone differences during this period of life. Pregnant adolescents may possess unique biological or psychological characteristics compared to adults and non-pregnant adolescents. Thus, we need to know more about the hypothalamic-pituitary-adrenocortical axis of pregnant adolescents.

Adolescent↗
PubMed2001

Saffman-Taylor problem on a sphere.

The Saffman-Taylor problem addresses the morphological instability of an interface separating two immiscible, viscous fluids when they move in a narrow gap between two flat parallel plates (Hele-Shaw cell). In this work, we extend the classic Saffman-Taylor situation, by considering the flow between two curved, closely spaced, concentric spheres (spherical Hele-Shaw cell). We derive the mode-coupling differential equation for the interface perturbation amplitudes and study both linear and nonlinear flow regimes. The effect of the spherical cell (positive) spatial curvature on the shape of the interfacial patterns is investigated. We show that stability properties of the fluid-fluid interface are sensitive to the curvature of the surface. In particular, it is found that positive spatial curvature inhibits finger tip-splitting. Hele-Shaw flow on weakly negative, curved surfaces is briefly discussed.

Journal Article↗
PubMed2001

Congenital aneurysm of the right atrium.

Congenital aneurysm of the right atrium is described in a 1-year-old girl who presented with cardiomegaly and symptoms of paroxysmal supraventricular tachycardia. Echocardiography and cineangiography both established the definitive diagnosis and surgical resection was successful. The rarity of this condition is pointed out and its main features outlined.

Female↗
PubMed2001

Endomyocardial fibrosis in children.

We describe 10 children with endomyocardial fibrosis who underwent surgical treatment between 1978 and 1999. Seven were male and 3 female, with an age range from 4 to 15 years, having a mean age of 11 years. All were in the final stage of heart failure. Three had biventricular disease, 6 had involvement of the right ventricle alone, and one had endomyocardial fibrosis confined to the left ventricle. There were 3 deaths (30%) in the postoperative period due to low cardiac output. The 7 survivors were followed up for a period ranging from 12 to 168 months, with a mean of 72 months. Two late deaths have occurred resulting from heart failure and infectious endocarditis. Five (50%) children are still alive. Two required 3 reoperations for dysfunction of the inserted valvar prosthesis. One patient is in functional Class IV, and 4 are in Class II to III, despite intensive medical treatment. It is concluded that surgery for endomyocardial fibrosis is an essentially palliative procedure and, especially in children, the results of surgical treatment leave much to be desired.

Adolescent↗
PubMed2000

Gravity-driven instability in a spherical Hele-Shaw cell.

A pair of concentric spheres separated by a small gap form a spherical Hele-Shaw cell. In this cell an interfacial instability arises when two immiscible fluids flow. We derive the equation of motion for the interface perturbation amplitudes, including both pressure and gravity drivings, using a mode coupling approach. Linear stability analysis shows that mode growth rates depend upon interface perimeter and gravitational force. Mode coupling analysis reveals the formation of fingering structures presenting a tendency toward finger tip-sharpening.

Journal Article↗
PubMed1999

Surgery for endomyocardial fibrosis revisited.

OBJECTIVE: To identify life expectancy after surgery for endomyocardial fibrosis (EMF) and the events that influence it. METHODS: Eighty-three patients with EMF underwent endocardial decortication and atrioventricular valve replacement or repair, between December 1977 and December 1997. There were 66 (79.6%) female and 17 (20.4%) male patients, ranging in age from 4 to 59 years (mean, 31). Thirty-seven (44.5%) had biventricular disease, 34 (41.0%) had disease of the right ventricle alone and 12 (14.5%) had EMF confined to the left ventricle. All were in functional class III or IV (New York Heart Association classification). RESULTS: Sixty-eight (81.9%) patients survived the operation and were followed up for periods ranging from 2 months to 17 years. The total follow-up time was 6290 patient/months (mean, 92 months). There were 15 late deaths, but in six, the cause was not related to the underlying disease. Four (5.8%) patients presented recurrence of the fibrosis and were reoperated on and in six (8.8%), EMF appeared in the other ventricle. Five (7.3%) patients were reoperated on to replace either a valve prosthesis or a native valve which had been preserved during the first procedure. Only 24 (45%) of the 53 surviving patients are in functional class I or II. The actuarial probability of survival at 17 years, including operative mortality, was 55%. CONCLUSION: Surgical treatment of EMF should be considered a palliative procedure because surgery does not alter the progressive nature of the disease. However, surgical therapy is recommended for patients with EMF and heart failure as it is their only hope of survival.

Adolescent↗
PubMed1999

Obstruction of the right ventricular outflow tract caused by a tuberculoma in a patient with ventricular septal defect and aneurysm of the membranous septum.

Reported here is an obstruction of the right ventricular outflow tract caused by a tuberculoma in a 15-year-old boy who presented with a ventricular septal defect. The obstruction was discovered at surgery and the tuberculous aetiology was only demonstrated histologically. To the authors' knowledge, this is the first report of a tuberculoma of the heart associated with congenital heart disease.

Adolescent↗
PubMed1996

Relationship between type of outflow tract repair and postoperative right ventricular diastolic physiology in tetralogy of Fallot. Implications for long-term outcome.

BACKGROUND: Restrictive right ventricular (RV) physiology can be present early and late after tetralogy of Fallot repair. It is associated with a complicated early postoperative course but is favorable late after repair because it is associated with less pulmonary regurgitation, better exercise tolerance, and less QRS prolongation and symptomatic ventricular arrhythmias. It is not known, however, whether in the current surgical era, this physiology is present in tetralogy of Fallot patients at mid-term follow-up and whether it is related to the type of RV outflow tract repair. Finally, the impact of this physiology on the early evolution of QRS prolongation has not been examined previously. In this study we attempted to address these issues in a cohort of recently operated patients. METHODS AND RESULTS: Ninety-five patients were studied 4.3 years after repair by Doppler echocardiography, serial electrocardiograms, and chest radiographs. Restrictive RV physiology defined by the presence of antegrade pulmonary artery flow in late diastole was present in 38% of the patients. It was more common in patients with transannular patch (TAP) repair compared with non-TAP repair (50% versus 21%, P < .05). QRS duration at follow-up was 121.2 +/- 17.6 and 132.6 +/- 11.8 ms in restrictive and nonrestrictive patients with TAP repair, respectively (P < .02). CONCLUSIONS: Restrictive RV physiology has been identified at mid-term follow-up in a contemporary surgical series. It is associated with less QRS prolongation, regardless of the technique used for outflow tract repair, and may be associated with fewer long-term complications. Nonrestrictive physiology is associated with the most marked QRS prolongation. This subgroup is most at risk from the late deleterious consequences of chronic pulmonary regurgitation.

Adolescent↗
PubMed1996

Anomalous origin of left coronary artery. Evolution of surgical treatment.

OBJECTIVE: To evaluate contemporary surgical techniques in the correction of anomalous origin of the left coronary artery from the pulmonary artery. METHODS: Eleven infants were operated upon during a ten year period by one surgeon. The anomalous coronary artery arose from the main pulmonary artery in ten and the right pulmonary artery in one patient. Direct reimplantation used in eight and the intra-pulmonary artery tunnel technique in three. Delayed sternal closure was used in the immediate post-operative period in five patients. RESULTS: There were no deaths within the 30 day post-operative period. At cardiac catheterisation and coronary angiography in seven patients, six showed normal left ventricular function and serial improvement of left ventricular shortening fractions. Pulmonary artery obstruction and aortopulmonary communications were observed in two patients in which the tunnel technique was used. One patient has required transplantation of the heart. CONCLUSION: Direct reimplantation is probably always possible and is the operation of choice. In the short and intermediate term there is improvement of left ventricular function in most patients.

Cardiac Surgical Procedures↗
PubMedDate not supplied

Peptic disease and Helicobacter pylori are highly prevalent in patients with the indeterminate form of Chagas' disease: report of 21 cases.

Given that chagasic patients in the indeterminate form of this disease, can have abnormal motility of the digestive tract and immunologic abnormalities, we decided to assess the frequency of peptic disease and Helicobacter pylori (Hp) infection in these individuals. Twenty-one individuals, 13 males and 8 females, mean age 37.6 +/- 11.1 years, were examined. Biopsies of the duodenum, antrum, lesser and greater gastric curvature and esophagus were performed. The endoscopic findings were of chronic gastritis in 20 (95.2%) patients, duodenal ulcer in 3 (14.3%), gastric and duodenal ulcer in 3 (14.3%), gastric ulcer alone in 1 (4.8%), esophagitis in 5 (23.8%), and duodenitis in 5 (23.8%). The diagnosis of infection by the Hp was done by the urease test and histologic examination. Hp infection was found in 20 (95.2%) individuals: in 20 out of them in the antrum, in 17 in the lesser curvature, and in 17 in the greater curvature. Hp was not found in the esophagus and duodenum. The only individual with no evidence of infection by Hp was also the only one with normal endoscopic and histologic examinations. The histologic examinations confirmed the diagnoses of gastric ulcer as peptic, chronic gastritis in 20 patients, duodenitis in 14, and esophagitis in 9. In this series the patients had a high frequency of peptic disease, which was closely associated with Hp infection.

Adolescent↗