Dengue Encephalopathy or Dengue Encephalitis? You Decide.

Awareness of neurological sequelae of dengue fever is increasing. However, as this case illustrates, there is a diagnostic conundrum in determining whether certain features are in keeping with dengue encephalopathy or dengue encephalitis. Further consensus is required.

The first evidence of hepatitis A virus subgenotype IIIA in the Eastern Brazilian Amazon, 1982-1983.

Hepatitis A virus (HAV) is a major causative agent of acute hepatitis worldwide. Although discovered in 1973, due to limitations of applicable serological and/or molecular methods, HAV remained under limited diagnosis until the late 1980s. This study aimed to retrospectively evaluate the serological and molecular prevalence of the HAV infection among 421 (n = 421) patients with a clinical and laboratory suspicion of acute hepatitis who were admitted in a reference laboratory in the Brazilian Eastern Amazon during 1982 and 1983. The 421 serum samples were screened for anti-HAV IgM antibodies by enzymatic immunoassays. Positive samples were submitted to total RNA purification and tested by Nested reverse-transcription polymerase chain reaction to amplify the HAV-RNA VP1-2A (522 bp) region. Anti-HAV IgM antibodies were detected in 66% (278/421) of the patients. The highest prevalence was observed among males (57.9%, 161/278), and most often among children under 10 years old (63.3%, 176/278). HAV-RNA was detected in 74.4% (207/278) of anti-HAV IgM positive samples. HAV genotyping was performed in 71 samples, and 69 were classified into subgenotype IA. Two samples belonged to the HAV subgenotype IIIA. In this sense, retrospective studies can help in understanding the evolution and determination of wild genotypes and subtypes of HAV.

Acute effects of expiratory positive pressure on autonomic cardiac modulation during spontaneous and slow deep breathing in COPD patients.

AIM: to evaluate the acute effects of expiratory positive airway pressure on cardiac autonomic modulation in chronic obstructive pulmonary disease patients during spontaneous breathing and slow deep breathing. METHODS: 17 patients were evaluated. The R-R intervals were collected (Polar® S810i) during spontaneous breathing (10 minutes) and slow deep breathing (4 minutes), with and without 5 cmH2O expiratory positive airway pressure. Stable signals were analyzed by Kubios®. Heart rate variability indices were computed in time domain and in frequency domain. RESULTS: Expiratory positive airway pressure application affected low frequency (spontaneous breathing: 62.5±4.1 vs slow deep breathing: 28.2±4.2, p<0.001) and high frequency (spontaneous breathing: 37.4±17.3 vs slow deep breathing: 58.9±18.1, p<0.001). Interactions were observed between expiratory positive airway pressure effect and slow deep breathing effect for low frequency (p<0.001), high frequency (p<0.001) and low frequency/high frequency ratio (p<0.001). When patients were stratified by disease's severity, we identified a significant low frequency reduction (p<0.001) and high frequency increase (p<0.001) for all stages when slow deep breathing was associated with expiratory positive airway pressure. CONCLUSION: A 5 cmH2O expiratory positive airway pressure during spontaneous and slow deep breathing can elicit an acute response, resulting in a cardiac autonomic control improvement in moderate-to-very severe patients.

Thoracoabdominal mobility evaluation of asthmatic patients in physiotherapy practice: Intra-rater reliability.

BACKGROUND: The evaluation of thoracoabdominal mobility is a tool extensively used in the physiotherapy practice in different populations. Photogrammetry may be a simple tool to analyse thoracoabdominal mobility; however, it is unclear whether this assessment can be a reliable method. AIM: To test the reliability intra-examinator by photogrammetry in asthmatic patients and in health controls. METHODS: Twenty-six asthmatic patients (29 ± 9 years) and 14 healthy matched controls (27 ± 8 years) were assessed by thoracoabdominal mobility. Photographs during rest, during inspiration and expiration maximum were used to calculate latero-lateral and antero-posterior diameters of the thorax (at axillary and xiphoid levels) and umbilical by markers positioned in osseous structures. An evaluator obtained the same measurements in an 8-day interval. RESULTS: We found a moderate reliability for axillary, xiphoid and umbilical mobility (average intraclass correlation coefficient [ICC] respectively [0.68, 0.55 and 0.73]) for asthmatic group. In addition, for control group, we found a moderate reliability for axillary mobility (average ICC respectively [0.68] and a good reliability for xiphoid and umbilical mobility) (average ICC 0.81 and 0.70). Bland-Altman plots showed goods limit of agreement in photos 1 and 2 in both groups. CONCLUSION: The photogrammetric analysis of thoracoabdominal mobility presented itself as a reliable method and may be used in clinical practice in asthmatic patients and in controls.

Deoxyribonucleic acid damage and repair response in the chemotherapy of lung cancer: cross-sectional study.

This study evaluated 24 patients with lung cancer (CA) and 23 individuals with no smoking history or cancer in the family and without respiratory disease in childhood (CO). Peripheral blood lymphocytes was used to perform alkaline comet assay and to assess DNA damage as well as to evaluate methyl methane sulfonate (MMS) DNA repair after one hour and three hours at 37 ºC. The percentage of residual damage (RD) after three hours of MMS treatment, for each patient was assessed. The majority of patients were in the CA group, male patients, former smokers, with a history of smoking for 15 years and without associated comorbidities. Alkaline and residual damages were higher in the CA group when compared to controls (alkaline damage P = 0.015 and RD P = 0.05). After one hour of MMS treatment the DNA damage of the CA increased indicating failure to repair it, compared to the controls, and after three hours DNA repair was observed in both groups. Patients with lung cancer are mostly men, former smokers and with more than 15 years of tobacco consumption, undergoing chemotherapy, have high rates of DNA damage and deficiency in their ability to repair against induced damage when compared to controls.

Exercise Training Does Improve Cardiorespiratory Fitness in Post-Bariatric Surgery Patients.

Although exercise is recognized as an important component of the management for patients following bariatric surgery (BS), its effectiveness on cardiorespiratory fitness (CRF) is still unclear. To investigate this relationship between BS and CRF, a systematic review was conducted in the MEDLINE database. The literature search included studies involving exercise training in patients following BS. A total of 306 studies were identified, 7 met the criteria and were included in the meta-analysis. Exercise training was found to result in a moderate and significant increase in VO2max (SMD = 0.430, 95% CI 0.157; 0.704, p = 0.002) following BS. The results from this meta-analysis indicate that exercise training can significantly improve CRF. Further research is needed to determine the ideal training duration and exercise training parameters for patients following BS.

Nongenomic effects of estradiol on aggression under short day photoperiods.

In several vertebrate species, the effects of estrogens on male aggressive behavior can be modulated by environmental cues. In song sparrows and rodents, estrogens modulate aggression in the nonbreeding season or winter-like short days, respectively. The behavioral effects of estrogens are rapid, which generally is considered indicative of nongenomic processes. The current study further examined the hypothesis that estradiol acts nongenomically under short days by utilizing a protein synthesis inhibitor, cycloheximide (CX). Mice were housed in either short or long day photoperiods, and treated with an aromatase inhibitor. One hour before resident-intruder testing mice were injected with either CX or saline vehicle, and 30 min later were treated orally with either cyclodextrin conjugated estradiol or vehicle. Under short days, mice treated with estradiol showed a rapid decrease in aggressive behavior, independent of CX administration. CX alone had no effect on aggression. These results show that protein synthesis is not required for the rapid effects of estradiol on aggression, strongly suggesting that these effects are mediated by nongenomic processes. We also showed that estradiol suppressed c-fos immunoreactivity in the caudal bed nucleus of the stria terminalis under short days. No effects of estradiol on behavior or c-fos expression were observed in mice housed under long days. Previously we had also demonstrated that cage bedding influenced the directional effects of estrogens on aggression. Here, we show that the phenomenon of rapid action of estradiol on aggression under short days is a robust result that generalizes to different bedding conditions.

Sex differences in stress-induced social withdrawal: independence from adult gonadal hormones and inhibition of female phenotype by corncob bedding.

There is compelling evidence for important sex differences in behavioral and hormonal responses to psychosocial stress. Here we examined the effects of gonadal hormones on behavioral responses to social defeat stress in monogamous California mice (Peromyscus californicus). Three episodes of social defeat induced social withdrawal in intact females but not males. Gonadectomy blocked corticosterone responses to defeat in females and sensitized male corticosterone responses. However, gonadectomy had no effects on social interaction behavior, suggesting that social withdrawal is not dependent on gonadal hormones in the adult California mouse. In contrast, defeat reduced exploratory behavior in the open field test for intact but not castrated males. We also examined the effects of social defeat on social interaction behavior when California mice were raised on corncob bedding, which has estrogenic properties. In this dataset of over 300 mice, we observed that social defeat did not induce social withdrawal when females were raised on corncob bedding. This finding suggests that the use of corncob in rodent studies could mask important sex differences in the effects of stress on brain and behavior. Although gonadal hormones do not affect social withdrawal behavior in adults, our data suggest that hormones may act earlier in development to induce a more resilient social phenotype.

Sex differences in social interaction behavior following social defeat stress in the monogamous California mouse (Peromyscus californicus).

Stressful life experiences are known to be a precipitating factor for many mental disorders. The social defeat model induces behavioral responses in rodents (e.g. reduced social interaction) that are similar to behavioral patterns associated with mood disorders. The model has contributed to the discovery of novel mechanisms regulating behavioral responses to stress, but its utility has been largely limited to males. This is disadvantageous because most mood disorders have a higher incidence in women versus men. Male and female California mice (Peromyscus californicus) aggressively defend territories, which allowed us to observe the effects of social defeat in both sexes. In two experiments, mice were exposed to three social defeat or control episodes. Mice were then behaviorally phenotyped, and indirect markers of brain activity and corticosterone responses to a novel social stimulus were assessed. Sex differences in behavioral responses to social stress were long lasting (4 wks). Social defeat reduced social interaction responses in females but not males. In females, social defeat induced an increase in the number of phosphorylated CREB positive cells in the nucleus accumbens shell after exposure to a novel social stimulus. This effect of defeat was not observed in males. The effects of defeat in females were limited to social contexts, as there were no differences in exploratory behavior in the open field or light-dark box test. These data suggest that California mice could be a useful model for studying sex differences in behavioral responses to stress, particularly in neurobiological mechanisms that are involved with the regulation of social behavior.

Sex differences in hormonal responses to social conflict in the monogamous California mouse.

Monogamous species are usually considered to be less likely to exhibit sex differences in behavior or brain structure. Most previous studies examining sex differences in stress hormone responses have used relatively sexually dimorphic species such as rats. We examined the stress hormone responses of monogamous California mice (Peromyscus californicus) to resident-intruder tests. We also tested males and females under different photoperiods, because photoperiod has been shown to affect both aggression and stress hormone responses. Females, but not males showed a significant increase in corticosterone levels immediately following a resident-intruder test. Males but not females showed elevated corticosterone levels under short days. Females tested in aggression tests also showed a significant increase in plasma oxytocin levels, but only when housed in long days. This was consistent with our observation that females but not males had more oxytocin positive cells in the paraventricular nucleus (PVN) when housed under long days. Our data show that sex differences in glucocorticoid responses identified in other rodents are present in a monogamous species.

Effects of photoperiod and experience on aggressive behavior in female California mice.

Aggressive behavior among females is observed in many species, but the mechanisms of this behavior have historically been understudied. In many species of rodents, winter-like short day photoperiods induce increased aggression levels compared to summer-like long day photoperiods. Recent reports in hamsters show that short days also increase aggression in females. We examined the effects of photoperiod on aggression in female California mice, and for the first time compare brain activity of aggression-tested female rodents under different photoperiods. We observed that female California mice were more aggressive when housed in short days versus long days. Intriguingly, we also observed that under long days female attack latency decreases with repeated testing in resident-intruder tests. These data suggest that winner effects that have been described in males may also occur in females. We also used the expression of phosphorylated extracellular signal-regulated kinases (pERK) in the brain to estimate brain activity during aggression tests. pERK can alter neuronal activity in the short term and in the long term can act as a transcription factor. Using immunoblot analyses we observed that aggression-induced pERK expression in the female bed nucleus of the stria terminalis and medial amygdala occurs under both long and short days. Thus, the mechanisms controlling increased aggression under short days are still unclear and additional study is needed.