Hantavirus pulmonary syndrome: prognostic factors for death in reported cases in Brazil

Hantavirus pulmonary syndrome (HPS) was described for the first time in Brazil in 1993 and has occurred endemically throughout the country. This study analysed clinical and laboratory aspects as well as death-related factors for HPS cases in Brazil from 1993 to 2006. The investigation comprised a descriptive and exploratory study of the history of cases as well as an analytical retrospective cohort survey to identify prognostic factors for death due to HPS. A total of 855 Brazilian HPS cases were assessed. The majority of cases occurred during spring (33.5%) and winter (27.6%), mainly among young male adults working in rural areas. The global case fatality rate was 39.3%. The mean interval between the onset of symptoms and hospitalisation was 4 days and that between hospitalisation and death was 1 day. In the multiple regression analysis, adult respiratory distress syndrome and mechanical respiratory support were associated with risk of death; when these two variables were excluded from the model, dyspnoea and haemoconcentration were associated with a higher risk of death. (C) 2012 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

The Extracellular Matrix of the Lateral Pharyngeal Wall in Obstructive Sleep Apnea

Study Objectives: To compare the components of the extracellular matrix in the lateral pharyngeal muscular wall in patients with and without obstructive sleep apnea (OSA). This may help to explain the origin of the increased collapsibility of the pharynx in patients with OSA. Design: Specimens from the superior pharyngeal constrictor muscle, obtained during pharyngeal surgeries, were evaluated using histochemical and immunohistochemical analyses to determine the fractional area of collagen types I and II, elastic fibers, versican, fibronectin, and matrix metalloproteinases 1 and 2 in the endomysium. Setting: Academic tertiary center. Patiens: A total of 51 nonobese adult patients, divided into 38 patients with OSA and 13 nonsnoring control subjects without OSA. Interventions: Postintervention study performed on tissues from patients after elective surgery. Measurements and Results: Pharyngeal muscles of patients with OSA had significantly more collagen type I than pharyngeal muscles in control subjects. Collagen type I was correlated positively and independently with age. The other tested components of the extracellular matrix did not differ significantly between groups. In a logistic regression, an additive effect of both the increase of collagen type I and the increase in age with the presence of OSA was observed (odds ratio (OR), 2.06; 95% confidence interval (CI), 1.17-3.63), when compared with the effect of increased age alone (OR, 1.11; 95% CI, 1.03-1.20). Conclusion: Collagen type I in the superior pharyngeal constrictor muscle was more prevalent in patients with OSA and also increased with age. It was hypothesized that this increase could delay contractile-relaxant responses in the superior pharyngeal constrictor muscle at the expiratory-inspiratory phase transition, thus increasing pharyngeal collapsibility.

Craniofacial morphology and sleep apnea in children with obstructed upper airways: Differences between genders

Objective: To correlate sleep apnea with craniofacial characteristics and facial patterns according to gender. Methods: In this prospective survey we studied 77 male and female children (3-12 years old) with an upper airway obstruction due to tonsil and adenoid enlargement. Children with lung problems, neurological disorders and syndromes, obstructive septal deviation, previous orthodontic treatment, orthodontic surgeries or oral surgeries, or obesity were excluded. Patients were subjected to physical examinations, nasal fiberoptic endoscopy, teleradiography for cephalometric analysis, and polysomnography. Methods: Cephalometric analysis included the following skeletal craniofacial measurements: facial axis (FA), facial depth (FD), mandibular plane angle (MP), lower facial height (LFH), mandibular arch (MA), and vertical growth coefficient (VERT) index. Results: The prevalence of sleep apnea was 46.75% with no statistical difference between genders. Among children with obstructive sleep apnea (Apneia Hypopnea Index - AHI >= 1) boys had higher AHI values than girls. A predominance of the dolichofacial pattern (81.9%) was observed. The following skeletal craniofacial measurements correlated with AHI in boys: FD (r(s) = -0.336/p = 0.020), MP (r(s) = 0.486/p = 0.00), and VERT index (r(s) = -0.337/p = 0.019). No correlations between craniofacial measurements and AHI were identified in girls. Conclusions: Craniofacial morphology may influence the severity of sleep apnea in boys but not in girls. (C) 2012 Elsevier B.V. All rights reserved.

Ambulatory blood pressure monitoring in children with obstructive sleep apnea and primary snoring

Objective: To evaluate the systemic blood pressure (BP) during daytime and nighttime in children with sleep breathing disorders (SBD) and compare parameters of BP in children with diagnosis of obstructive sleep apnea syndrome (OSA) to those one with primary snoring (PS). Methods: Children, both genders, aged from 8 to 12 years, with symptoms of SBD realized an overnight polysomnography followed by a 24 h recording of ambulatory BP. Results: All subjects presented with a history of snoring 7 nights per week. Children who have apnea/hipoapnea index >= four or a apnea index >= one presented a mean BP of 93 +/- 7 mmHg and 85 +/- 9 mmHg diurnal and nocturnal respectively whereas children who have a apnea/hipoapnea < four or a apnea index < one presented 90 +/- 7 mmHg and 77 +/- 2 mmHg. Eight children out of fourteen, from OSA group, lost the physiologic nocturnal dipping of the blood pressure. Among OSA children 57% were considered non-dippers. Two (16%) have presented absence of nocturnal dipping among children with primary snoring. The possibility of OSA children loosing physiologic blood pressure dipping was 6.66 higher than the possibilities of patients from PS group. Discussion: Our results indicate that children with sleep apnea syndrome exhibit a higher 24 h blood pressure when compared with those of primary snoring in form of decreased degree of nocturnal dipping and increased levels of diastolic and mean blood pressure, according to previous studies in literature. OSA in children seems to be associated to the development of hypertension or other cardiovascular disease. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

Isolation, enzymatic characterization and antiedematogenic activity of the first reported rattlesnake hyaluronidase from Crotalus durissus terrificus venom

A hyaluronidase (CdtHya1) from Crotalus durissus terrificus snake venom (CdtV) was isolated and showed to exhibit a high activity on hyaluronan cleavage. However, surveys on this enzyme are still limited. This study aimed at its isolation, functional/structural characterization and the evaluation of its effect on the spreading of crotoxin and phospholipase A(2) (PLA(2)). The enzyme was purified through cation exchange, gel filtration and hydrophobic chromatography. After that, it was submitted to a reverse-phase fast protein liquid chromatography (RP-FPLC) and Edman degradation sequencing, which showed the first N-terminal 44 amino acid residues whose sequence evidenced identity with other snake venom hyaluronidases. CdtHya1 is a monomeric glycoprotein of 64.5 kDa estimated by SDS-PAGE under reducing conditions. It exhibited maximum activity in the presence of 0.2 M NaCl, at 37 degrees C, pH 5.5 and a specificity to hyaluronan higher than that to chondroitin-4-sulphate, chondroitin-6-sulphate or dermatan. Divalent cations (Ca2+ and Mg2+) and 1 M NaCl significantly reduced the enzyme activity. The specific activity of CdtHya1 was 5066 turbidity reducing units (TRU)/mg, against 145 TRU/mg for the soluble venom, representing a 34.9-fold purification. The pure enzyme increased the diffusion of crotoxin and PLA (2) through mice tissues. CdtHya1 (32 TRU/40 mu L) potentiated crotoxin action, as evidenced by mice death, and it decreased the oedema caused by subplantar injections of buffer, crotoxin or PLA(2), thus evidencing the relevance of hyaluronidase in the crotalic envenoming. This work yielded a highly active antiedematogenic hyaluronidase from CdtV, the first one isolated from rattlesnake venoms. (C) 2012 Elsevier Masson SAS. All rights reserved.

Observational study on efficacy of negative expiratory pressure test proposed as screening for obstructive sleep apnea syndrome among commercial interstate bus drivers - protocol study

Abstract Background Obstructive sleep apnea (OSA) is a respiratory disease characterized by the collapse of the extrathoracic airway and has important social implications related to accidents and cardiovascular risk. The main objective of the present study was to investigate whether the drop in expiratory flow and the volume expired in 0.2 s during the application of negative expiratory pressure (NEP) are associated with the presence and severity of OSA in a population of professional interstate bus drivers who travel medium and long distances. Methods/Design An observational, analytic study will be carried out involving adult male subjects of an interstate bus company. Those who agree to participate will undergo a detailed patient history, physical examination involving determination of blood pressure, anthropometric data, circumference measurements (hips, waist and neck), tonsils and Mallampati index. Moreover, specific questionnaires addressing sleep apnea and excessive daytime sleepiness will be administered. Data acquisition will be completely anonymous. Following the medical examination, the participants will perform a spirometry, NEP test and standard overnight polysomnography. The NEP test is performed through the administration of negative pressure at the mouth during expiration. This is a practical test performed while awake and requires little cooperation from the subject. In the absence of expiratory flow limitation, the increase in the pressure gradient between the alveoli and open upper airway caused by NEP results in an increase in expiratory flow. Discussion Despite the abundance of scientific evidence, OSA is still underdiagnosed in the general population. In addition, diagnostic procedures are expensive, and predictive criteria are still unsatisfactory. Because increased upper airway collapsibility is one of the main determinants of OSA, the response to the application of NEP could be a predictor of this disorder. With the enrollment of this study protocol, the expectation is to encounter predictive NEP values for different degrees of OSA in order to contribute toward an early diagnosis of this condition and reduce its impact and complications among commercial interstate bus drivers.

Behavioral problems and emotional stress in children with bruxism

Bruxism has a multifactorial etiology, and psychosocial factors have been considered to increase the risk of occurrence of this parafunction. The aim of this study was to evaluate the behavior profile of a group of children diagnosed with bruxism. Eighty 7-11-year-old children of both genders (mean age 8.8 years) first recruited as eligible participants. Twenty-nine children (18 males and 11 females) whose parents/guardians reported to present frequent episodes of tooth grinding/clenching while awake or during sleep (at least 3 nights a week) in the previous 3 months were enrolled in the study. The diagnosis of bruxism was established based on the parents/guardians' report about the children's behavior, habits and possible discomforts in the components of the stomatognathic system allied to the presence of signs and symptoms such as pain on the masticatory muscles, masseter muscle hypertrophy, wear facets, fractures of restorations, dental impressions on the cheek mucosa and tongue. As part of the psychological evaluation, the Rutter's Child Behavior Scale-A2 was applied to the parents/caregivers (one for each child) and the Child Stress Scale was applied to the children. Data were analyzed descriptively based on the frequency of each studied variable. Twenty-four (82.76%) children needed psychological or psychiatric intervention; 17 of them presented neurotic disorders and 7 children presented antisocial disorders. Six (20.70%) children presented significant physical and psychological manifestations of stress. The findings of the present study suggest that behavioral problems and potential emotional problems can be risk factors to bruxism in children.

Maternal immune activation increases the corticosterone response to acute stress without affecting the hypothalamic monoamine content and sleep patterns in male mice offspring

Background/Aims: Early life experiences are homeostatic determinants for adult organisms. We evaluated the impact of prenatal immune activation during late gestation on the neuroimmune-endocrine function of adult offspring and its interaction with acute stress. Methods: Pregnant Swiss mice received saline or lipopolysaccharide (LPS) on gestational day 17. Adult male offspring were assigned to the control or restraint stress condition. We analyzed plasmatic corticosterone and catecholamine levels, the monoamine content in the hypothalamus, striatum and frontal cortex, and the sleep-wake cycle before and after acute restraint stress. Results and Conclusion: Offspring from LPS-treated dams had increased baseline norepinephrine levels and potentiated corticosterone secretion after the acute stressor, and no effect was observed on hypothalamic monoamine content or sleep behavior. The offspring of immune-activated dams exhibited impairments in stress-induced serotonergic and dopaminergic alterations in the striatum and frontal cortex. The data demonstrate a distinction between the plasmatic levels of corticosterone in response to acute stress and the hypothalamic monoamine content and sleep patterns. We provide new evidence regarding the influence of immune activation during late gestation on the neuroendocrine homeostasis of offspring.