Renata Guedes Koyama

Can energy drinks reduce the depressor effect of ethanol? An experimental study in mice

Although the popularization of the combined use of alcoholic beverages and energy drinks (ED) containing caffeine, taurine and other substances has increased, there are no controlled experimental studies on the effects of ED alone or combined with ethanol. This work aimed at evaluating the effects of different doses of ED combined or not with ethanol, on the locomotor activity of Swiss mice. The administration of 3.57, 10.71 or 17.86 ml/kg of ED alone increased the locomotor activity of the animals in relation to a control group. Low doses of ethanol (0.5, 1.0 and 1.5 g/kg) alone or in combination with 10.71 ml/kg of ED did not affect their locomotor activity. However, the reduction of activity observed after 2.5 g/kg of ethanol was antagonized by 10.71 ml/kg of ED. Further studies on the mechanisms of this interaction are still needed.

Reciprocal interactions of obstructive sleep apnea and hypertension associated with ACE I/D polymorphism in males

BACKGROUND The angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism gene contributes to the genesis of hypertension (HTN) and may help explain the relationship between obstructive sleep apnea (OSA) and HTN. However, ACE is a pleiotropic gene that has several influences, including skeletal muscle and control of ventilation. We therefore tested the hypothesis that ACE polymorphism influences OSA severity. METHODS Male OSA patients (apnea-hypopnea index [AHI]>5 events/h) from 2 university sleep centers were evaluated by polysomnography and ACE I/D polymorphism genotyping. RESULTS We studied 266 males with OSA (age=48+/-13 y, body mass index=29+/-5 kg/m(2), AHI=34+/-25 events/h). HTN was present in 114 patients (43%) who were older (p<0.01), heavier (p<0.05) and had more severe OSA (p<0.01). The I allele was associated with HTN in patients with mild to moderate OSA (p<0.01), but not in those with severe OSA. ACE I/D polymorphism was not associated with apnea severity among normotensive patients. In contrast, the only variables independently associated with OSA severity among patients with hypertension in multivariate analysis were BMI (OR=1.12) and II genotype (OR=0.27). CONCLUSIONS Our results indicate reciprocal interactions between OSA and HTN with ACE I/D polymorphism, suggesting that among hypertensive OSA males, the homozygous ACE I allele protects from severe OSA.

Prevalence of and risk factors for obstructive sleep apnea syndrome in Brazilian railroad workers

OBJECTIVE This study evaluated the prevalence of, and the risk factors for, obstructive sleep apnea syndrome (OSAS) among Brazilian railroad workers. METHODS Male railroad workers (745) from a railway company in Brazil were analyzed after responding to questionnaires about their demographics, sleep habits, excessive daytime sleepiness (Epworth), and the likelihood of having apnea (Berlin). We also performed polysomnography and measured anthropometric data for all of the railroad workers. RESULTS The results showed that 261 (35.03%) of the railroad workers presented with OSAS. These railroad workers were older (OSAS: 38.53±10.08 versus non-OSAS: 33.99±8.92 years), more obese according to body mass index (27.70±4.38 versus 26.22±3.92 kg/m(2)), and employed for a longer period of time (14.32±9.13 years) compared with those without OSAS (10.96±7.66 years). Among those with OSAS, 9.5% were smokers and 54.7% reported alcohol use. The associated risk factors were age (OR=2.51, 95% CI=1.76-3.57), BMI (OR=1.56, 95% CI=1.04-2.34), alcohol use (OR=1.28, 95% CI=0.90-1.81), and a high chance of having sleep apnea, as assessed by the Berlin questionnaire (OR=2.19, 95% CI=1.49-3.21). CONCLUSION The prevalence of OSAS in Brazilian railroad workers was higher than that observed in the general population but similar to that found in the population of the city of São Paulo, Brazil. These results suggest that age, BMI, a high risk of developing apnea through subjective self-reporting (Berlin), and alcohol use are associated with a higher risk of developing OSAS. These data reinforce the need to be more attentive to this population because they have a higher propensity for accidents.

Simple Detection of Large InDeLS by DHPLC: The ACE Gene as a Model

Insertion-deletion polymorphism (InDeL) is the second most frequent type of genetic variation in the human genome. For the detection of large InDeLs, researchers usually resort to either PCR gel analysis or RFLP, but these are time consuming and dependent on human interpretation. Therefore, a more efficient method for genotyping this kind of genetic variation is needed. In this report, we describe a method that can detect large InDeLs by DHPLC (denaturating high-performance liquid chromatography) using the angiotensin-converting enzyme (ACE) gene I/D polymorphism as a model. The InDeL targeted in this study is characterized by a 288 bp Alu element insertion (I). We used DHPLC at nondenaturating conditions to analyze the PCR product with a flow through the chromatographic column under two different gradients based on the differences between D and I sequences. The analysis described is quick and easy, making this technique a suitable and efficient means for DHPLC users to screen InDeLs in genetic epidemiological studies.

Robust evaluation of time since awakening using force platform posturography

INTRODUCTION: Sleepiness is responsible for a considerable proportion of traffic accidents. It is thus an important traffic safety issue to find a robust, objective and practical way to estimate the amount of time a person has been awake. To attempt to meet this goal, we investigated the relationship between sleepiness and posture control. METHODS: Subjects were kept awake for 36 hours and posturographic data during quiet standing were collected every two hours by means of a force platform. The standing surface (rigid surface or foam surface) and visual (eyes open or eyes closed) conditions were manipulated. RESULTS: In the more challenging conditions (with foam surface and/or eyes closed), the body sway variables derived from the center of the pressure measurement increased significantly when time since awakening became greater than 21 h in almost all subjects. CONCLUSION: Based on this result, we propose a practical protocol that could robustly assess whether time since awakening was greater than 21 h.

Maquinistas ferroviários: trabalho em turnos e repercussões na saúde

Objective to describe the impact of shiftwork on the health, sleep and quality of life of railway drivers. Methods six hundred eleven railway drivers (schedule 4x1 and 6x2) were evaluated by polysomnography, Pittsburgh Sleep Quality Index, Insomnia Severity Index, Work Capacity Index, Quality of Life questionnaire (SF-36), Morningness-eveningness questionnaire (MEQ), and Epworth Sleepiness Scale. 
Results railway drivers assessed were 36.6 ± 15.1 years of age, 22% were obese, and 38.1% presented risks for cardiovascular disease. Poor sleep quality 64.2%, 11.6% had sleep disorders and 29.3% excessive sleepiness. The polysomnography results showed that 36.1% of them presented sleep apnea and 47.2% had significant reduction in sleep efficiency. The railway drivers showed low levels of quality of life, especially those working under the 4x1 schedule. Conclusion it is possible to assert that exposure to shiftwork, reverse rotation schedule, few days off, and working overtime are associated with impairment to well-being, health, sociability and workers’ sleep quality, and the factors related to shiftwork probably contribute to these findings.