Development and perspective of current Brazilian studies on the epidemiology of childhood leukemia

In this concise report, we describe the history and evolution of childhood acute leukemia studies in Brazil, and the application if key biomarkers for clinical trials and epidemiological studies over the past 8 years. Highlights of each ongoing study are summarized. A Brazilian network integrating hospitals and scientific institutions from all country regions has been established. This organization is made possible through informatics and computer networking, and the standardization of pathological reviews including immunophenotyping and molecular characterization of childhood leukemias. The unique characteristics of the Brazilian population combined with a large clinical and epidemiologic framework for patient ascertainment has enabled large-scale epidemiological studies on childhood leukemia in Brazil.     

Effects of hormone therapy with estrogen and/or progesterone on sleep pattern in postmenopausal women

OBJECTIVE: To investigate the effects of estrogen and progesterone on sleep in postmenopausal women. METHOD: The 33 participants were randomly assigned to an estrogen or placebo group after undergoing clinical and hormonal assessments and a polysomnogram, and they underwent the same tests again after 12 weeks. Then, while still taking estrogen or placebo, they all received progesterone for another 12 weeks and underwent a final polysomnogram. RESULTS: Estrogen plus progesterone was more effective than estrogen alone in decreasing the prevalence of periodic limb movement (PLM) (8.1% vs 2.8%), hot flashes (14.2% vs 0%), and bruxism (11.1% vs 0%) at night, or somnolence and attention difficulty during the day. The prevalences of breathing irregularities, arousal from sleep, anxiety, and memory impairment were decreased in both groups following progesterone treatment. CONCLUSION: While not significantly affecting sleep quality, hormone therapy decreased the prevalence of arousal in both groups and that of PLM in the group treated with estrogen plus progesterone.     

Study of the Extent of the Information of Cardiologists from São Paulo City,Brazil, Regarding a Low‐Prevalence Entity: Brugada Syndrome

Objective: To determine the degree of knowledge that cardiologists from São Paulo, Brazil, have regarding a low‐prevalent entity associated with a high rate of sudden death—Brugada syndrome. Methods: Two hundred forty‐four cardiologists were interviewed by an instrument divided in two parts: in the first, we recorded gender, age, and data related to academic profile. The second—answered only by the professionals that manifested having some degree of knowledge on the syndrome—had 28 questions that evaluated their knowledge. The answers were spontaneous and they did not have a chance to consult. We used uni‐ and multivariate analysis on the average percentage of right and wrong answers, and the influence of the academic profile. Results: The predominant gender was the male gender (61.1%), the average age was 44.32 ± 10.83 years, 40% with more than 20 years after obtaining their degree, 44% were educated in public institutions, 69% had a residency in cardiology, 20% had overseas practice, 12% had postdegree, 41% were linked to an educational institution, 24% with publication(s) in an indexed journal, 17.2% were authors of chapters in books, 2.5% had edited books, and 10% were linked to the Brazilian Society of Cardiac Arrhythmias. The average percentage of right answers was 45.7%. Conclusion: The sample studied revealed a little knowledge on the entity. A residency in cardiology was the factor of greater significance in the percentage of right answers. Other significant factors were the link of the interviewed person to an educational institution, or the Brazilian Society of Cardiac Arrhythmias, and having a specialist degree.     

Cardiovascular symptoms and signs in evaluating cardiac murmurs in children

Background: The aim of the present study was to determine the usefulness of cardiovascular symptoms and signs in the recognition of significant congenital heart lesions that required surgical or catheter interventions in different pediatric age groups. Methods: A retrospective chart review was carried out of 110 patients with significant heart anomalies that required surgical or catheter interventions (group I) and 113 children, presenting with cardiac murmurs, with congenital heart conditions not requiring any interventions. (group II) Results: Clinical symptoms or signs were significantly more common in group I than in group II subjects (85% vs 32%, P < 0.0001). The odds of having significant lesions requiring interventions in the presence of either cardiovascular symptoms or signs were 37.5 (95% confidence interval [CI]: 6.5–218.1) for neonates, 14.5 (95%CI: 4.7–51.7) for infants, and 8.0 (95%CI: 3.3–19.2) for children and adolescents. In neonates, the negative predictive values of the absence of symptoms or signs in isolation were relatively low at 64% and 65%, respectively. In children beyond infancy, the positive predictive values of the presence of symptoms or signs in isolation were also low at 62% and 68%, respectively. Conclusions: Clinical assessment of cardiovascular symptoms and signs remains useful in the evaluation of the significance of pathological cardiac murmurs in children in the present era of technology. Nonetheless, the predictive values vary with different pediatric age groups.     

Automatic selection of tidal volume, respiratory frequency and minute ventilation in intubated ICU patients as startup procedure for closed-loop controlled ventilation

Objective: Before a patient can be connected to a mechanical ventilator, the controls of the apparatus need to be set up appropriately. Today, this is done by the intensive care professional. With the advent of closed loop controlled mechanical ventilation, methods will be needed to select appropriate startup settings automatically. The objective of our study was to test such a computerized method which could eventually be used as a start-up procedure (first 5–10 minutes of ventilation) for closed-loop controlled ventilation.Design: Prospective Study.Settings: ICU's in two adult and one children's hospital.Patients: 25 critically ill adult patients (age15 y) and 17 critically ill children selected at random were studied.Interventions: To simulate initial connection, the patients were disconnected from their ventilator and transiently connected to a modified Hamilton AMADEUS ventilator for maximally one minute. During that time they were ventilated with a fixed and standardized breath pattern (Test Breaths) based on pressure controlled synchronized intermittent mandatory ventilation (PCSIMV).Measurements and main results: Measurements of airway flow, airway pressure and instantaneous CO₂ concentration using a mainstream CO₂ analyzer were made at the mouth during application of the Test-Breaths. Test-Breaths were analyzed in terms of tidal volume, expiratory time constant and series dead space. Using this data an initial ventilation pattern consisting of respiratory frequency and tidal volume was calculated. This ventilation pattern was compared to the one measured prior to the onset of the study using a two-tailed paired t-test. Additionally, it was compared to a conventional method for setting up ventilators. The computer-proposed ventilation pattern did not differ significantly from the actual pattern (p>0.05), while the conventional method did. However the scatter was large and in 6 cases deviations in the minute ventilation of more than 50% were observed.Conclusions: The analysis of standardized Test Breaths allows automatic determination of an initial ventilation pattern for intubated ICU patients. While this pattern does not seem to be superior to the one chosen by the conventional method, it is derived fully automatically and without need for manual patient data entry such as weight or height. This makes the method potentially useful as a startup procedure for closed-loop controlled ventilation.     

Alterations of both responder T cells and stimulator non-T cells are responsible for abnormal mixed lymphocyte reaction in aged humans

Summary The autologous and allogeneic mixed lymphocyte reactions of 15 young and 15 aged human adults were compared. Both autologous and allogeneic mixed lymphocyte reactions were significantly reduced in the aged group. T cells from aged adults displayed a reduced proliferative response to non-T cells of either aged or young adults. T cells from young adults also showed a reduced proliferative response to non-T cells from aged adults. Sera from aged adults, showing depression of autologous and allogeneic mixed lymphocyte reaction, did not exert any inhibitory effect on the autologous and allogeneic mixed reaction of lymphocytes from young donors. These data suggest that depression of mixed lymphocyte reaction in aged humans probably reflects intrinsic abnormalities of both responder T cells and stimulatory non-T cells. This work was supported by a grant from theConsiglio Nazionale delle Ricerche (CNR), Roma, Italy ‘Progetto Finalizzato Medicina Preventiva, Sottoprogetto Meccanissmi di Invecchiamento’.