Daylight exposure and mood in real life: Direct association and mediating role of sleep and routine regularity.

The light/dark cycle is the main external cue to synchronize the human biological clock. Modern lifestyles typically lead to less daylight exposure and blunted 24 h-amplitude. We evaluated the association of outdoor daylight exposure (frequency, duration, regularity and shift) with chronotype estimated by sleep phase, regularity of routines, sleep, well-being (WHO-5), and depressive symptoms (PHQ-9), in a sample of 1,095 participants (81.8% female; 87.9% aged 18-49) surveyed online between July and November 2020. We analyzed direct and indirect associations in daylight-mood relationship with chronotype-estimate, routine regularity, and sleep as mediators. Outdoor daylight exposure was associated with WHO-5/PHQ-9 scores in mediation models, with higher total effects when the exposure was every day (ß = 4.13 ± 0.53/ ß = -3.81 ± 0.67), for more than 4 hours (ß = 3.77 ± 0.91/ ß = -3.83 ± 1.31) and during the morning (ß = 3.41 ± 0.53/ ß = -3.74 ± 0.70) in reference to lack of exposure. Chronotype-estimate, routine regularity score, and sleep problems acted as mediators, while social jetlag and sleep duration did not play an important role in this association. This study advanced the understanding of the complex interplay between light exposure, mental health, and individual characteristics of sleep and other routine regularities, and showed the benefits of optimizing daylight exposure to improve mental health.

Use of Light Protection Equipment at Night Reduces Time Until Discharge From the Neonatal Intensive Care Unit: A Randomized Interventional Study.

Newborn infants' circadian systems are not completely developed and rely on external temporal cues for synchronizing their biological rhythms to the environment. In neonatal intensive care units (NICUs), lighting is usually continuous or irregular and infants are exposed to artificial light at night, which can have negative health consequences. Therefore, the aim of this study was to evaluate the impact of the use of individual light protection equipment at night on the development and growth of preterm neonates. Infants born at less than 37 gestational weeks who no longer needed constant intensive care were admitted into a newborn nursery and randomized to either use eye masks at night (intervention, n = 21) or not (control, n = 20). Infants who used eye protection at night were discharged earlier than those in the control group (8 [5] vs 12 [3.75] days; p < 0.05). A greater variation within the day in heart rate was observed in the intervention group, with lower values of beats per minute at 1400 and 2000 h. There was no significant difference in weight gain between groups. In view of our results and of previous findings present in the literature, we suggest that combining a darkened environment at night with individual light protection devices creates better conditions for the development of preterm infants in the NICU. In addition, eye masks are an affordable and simple-to-use tool that can reduce hospitalization costs by decreasing the number of days spent in the NICU.

Effective recommendations towards healthy routines to preserve mental health during the COVID-19 pandemic

Objective: To assess the adherence to a set of evidence-based recommendations to support mental health during the coronavirus disease 2019 (COVID-19) pandemic and its association with depressive and anxiety symptoms. Methods: A team of health workers and researchers prepared the recommendations, formatted into three volumes (1: COVID-19 prevention; 2: Healthy habits; 3: Biological clock and sleep). Participants were randomized to receive only Volume 1 (control), Volumes 1 and 2, Volumes 1 and 3, or all volumes. We used a convenience sample of Portuguese-speaking participants over age 18 years. An online survey consisting of sociodemographic and behavioral questionnaires and mental health instruments (Patient Health Questionnaire-9 [PHQ-9] and Generalized Anxiety Disorder-7 [GAD-7]) was administered. At 14 and 28 days later, participants were invited to complete follow-up surveys, which also included questions regarding adherence to the recommendations. A total of 409 participants completed the study - mostly young adult women holding university degrees. Results: The set of recommendations contained in Volumes 2 and 3 was effective in protecting mental health, as suggested by significant associations of adherence with PHQ-9 and GAD-7 scores (reflecting anxiety and depression symptoms, respectively). Conclusion: The recommendations developed in this study could be useful to prevent negative mental health effects in the context of the pandemic and beyond.

Effective recommendations towards healthy routines to preserve mental health during the COVID-19 pandemic.

OBJECTIVE: To assess the adherence to a set of evidence-based recommendations to support mental health during the coronavirus disease 2019 (COVID-19) pandemic and its association with depressive and anxiety symptoms. METHODS: A team of health workers and researchers prepared the recommendations, formatted into three volumes (1: COVID-19 prevention; 2: Healthy habits; 3: Biological clock and sleep). Participants were randomized to receive only Volume 1 (control), Volumes 1 and 2, Volumes 1 and 3, or all volumes. We used a convenience sample of Portuguese-speaking participants over age 18 years. An online survey consisting of sociodemographic and behavioral questionnaires and mental health instruments (Patient Health Questionnaire-9 [PHQ-9] and Generalized Anxiety Disorder-7 [GAD-7]) was administered. At 14 and 28 days later, participants were invited to complete follow-up surveys, which also included questions regarding adherence to the recommendations. A total of 409 participants completed the study - mostly young adult women holding university degrees. RESULTS: The set of recommendations contained in Volumes 2 and 3 was effective in protecting mental health, as suggested by significant associations of adherence with PHQ-9 and GAD-7 scores (reflecting anxiety and depression symptoms, respectively). CONCLUSION: The recommendations developed in this study could be useful to prevent negative mental health effects in the context of the pandemic and beyond.

Translation and adaptation of the indoor environmental quality questionnaire to Brazilian portuguese

Introduction: Indoor environmental quality (IEQ) impacts well-being, performance, and mental and physical health. A questionnaire for assessing occupants' perception of IEQ was developed in English. This study aimed to translate this instrument into Brazilian Portuguese and adapt it to the Brazilian population.Methods: The translation and adaptation process consisted of forward translation, reconciliation, back translation, back translation review, harmonization, two cognitive debriefings, and finalization.Results: The final translated version included new questions and changed the scale to a visual-analog format. The clarity assessment showed that, after cognitive debriefings, all questions displayed satisfactory scores, with the majority rated higher than 9 on a 0-10 scale.Conclusions: The Brazilian Portuguese version of the IEQ questionnaire is a simple tool that can be employed in biomedical and building research to investigate the association of perceived IEQ with health-related parameters, as well as in architecture, engineering, and management projects. As a next step, a psychometric validation of the instrument will be performed.

Effect of reciprocating instrumentation on chlorhexidine substantivity on human dentin: chemical analysis followed by confocal laser microscopy

The present research analyzed the reciprocating instrumentation associated to chlorhexidine (CHX) substantivity as its correlation with E. faecalis viability in ex vivo root canals. Eighty extracted single-rooted human teeth were used, being 40 to high-performance liquid chromatography (HPLC) and 40 to confocal laser scanning microscopy (CLSM). In both, teeth were decoronated and the cervical third was prepared. In the CLSM analysis, the root canals were inoculated with E. faecalis for 14 days. Samples were divided into 4 groups (n=10) according to instrumentation technique: no instrumentation and irrigation with distilled water (control); manual instrumentation (K-File); rotary instrumentation (ProTaper Next); and reciprocating instrumentation (Reciproc R25). Two percent chlorhexidine was applied as irrigating substance in experimental groups. Longitudinal grooves resulted in 2 halves root and 20 proof bodies in each group. Samples were divided by chance in two groups (n=10) and the outcomes were evaluated after two days and one week. The retained chlorhexidine and live cells after instrumentation techniques in each evaluation time was measured by HPLC and CLSM, respectively. Specific analysis was applied for experimental tests (p≤0.05). Both rotary as well as reciprocating techniques significantly reduced the amount of chlorhexidine on dentin in all observation periods (p<0.05). After evaluation times, all experimental groups presented lower live cells compared to control, but without statistically difference. Intragroup comparisons in times of evaluation showed no differences in instrumentation techniques, in chlorhexidine retention and number of live cells (p>0.05). Reciprocating instrumentation does not interfere on chlorhexidine substantivity.

Effect of chemical and natural irrigant solutions on microhardness of root dentin­ an in vitro study

Aim: Modifications in the mechanical properties of dentin may reduce the fracture resistance of tooth, especially after endodontic treatment. The aim of present study was to evaluate the effect of the irrigation with different root canal irrigants on the microhardness of root dentin. Methods: The coronal portion of 60 single-rooted bovine incisors was sectioned and the pulpal tissue removed using endodontic K-files. The roots were cut transversely to obtain 2 fragments, which were embedded in acrylic resin and randomly distributed into six groups (n=20) according to the irrigation protocol: distilled water (DW) (control); 2% chlorhexidine solution (CHX); 6% sodium hypochlorite (NaOCl); 6% calcium hypochlorite (Ca[OCl]2); QMix; and 6.5% grape seed extract solution (GSE). The solutions were kept in contact with the root dentin specimens for 30 min. After that, irrigation with 5 mL of DW was performed. The Vickers microhardness was determined by performing three indentations in all specimens, using 300-g load and 20-second dwell time. The first indentation was made 1.000 µm from the root canal entrance, and two other indentations were made at a distance of 200 µm from each other. The microhardness value for each specimen was obtained as the average of the results for the three indentations. Data were statistically analyzed using one-way ANOVA with 5% significance level. Results: All the tested irrigant solutions maintained the same microhardness level of the root dentin when compared to the control group, with no statistically significant differences between them (p<0.05) Conclusion: The tested irrigant solutions did not present ability to modify the microhardness of root dentin

Effects of maternal protein malnutrition on oxidative markers in the young rat cortex and cerebellum.

Malnutrition affects a large number of children worldwide. Inadequate nutrition during pre- and postnatal period may alter brain development resulting in biochemical, physiological and anatomical changes which in turn could cause behavioral abnormalities. The impairment of the central nervous system following protein deficit have been extensively studied and this deprivation produces deleterious effects upon cerebral structures. The aim of this study was to identify oxidative parameters present in the developing brain as consequence of maternal protein malnutrition. Female Wistar rats were fed a normal protein diet (25% casein) or low protein diet (8% casein) from the time of conception up to 21 days after the parturition. In addition, the diets were supplemented or not with l-methionine. Cortex and cerebellum were removed from offspring to determine the activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and the levels of lipoperoxidation (TBARS). Our findings demonstrated heterogeneity in response to protein restriction. The levels of lipoperoxidation were increased in the cerebellum of malnourished offspring. Methionine supplementation caused an increase in lipoperoxidation in both brain structures. CAT activity was decreased in the cerebellum of the offspring supplemented with methionine whereas the cerebellum of malnourished pups with or not methionine supplementation showed a decrease in SOD activity. The activity of SOD in the cortex did not differ among groups. CAT activity, however, was increased in the cortex of malnourished pups supplemented or not with methionine. Thus, these results provide clues to the knowledge of malnutrition effects upon the brain.

Long lasting effects of electroconvulsive seizures on brain oxidative parameters.

This work was performed in order to determine the level of oxidative damage and antioxidant enzymes activities late after acute and chronic electroconvulsive shock (ECS) in rats. We measured oxidative parameters in hippocampus, cortex, and striatum, at 45, 60, 90 and 120 days after a single or multiple ECS. We demonstrated an increase in lipid peroxidation after multiple ECS in the hippocampus and striatum. This was also the case for protein carbonyls in the single or multiple protocols. In this way, we demonstrated an increase in catalase in cortex in contrast to striatum and hippocampus, were there were decreases sometimes in chronic ECS. The superoxide dismutase activities decrease in different times after single and multiple ECS in the hippocampus. Our findings demonstrated that there is a delayed increase after ECS in oxidative damage and decrease in antioxidant enzymes activities in hippocampus and striatum.

Oxidative stress effects on the central nervous system of rats after acute exposure to ultra high frequency electromagnetic fields.

Mobile telephones and their base stations are an important source of ultra high frequency electromagnetic fields (UHF-EMFs; 800-1800 MHz) and their utilization is increasing all over the world. Epidemiological studies have suggested that low energy UHF-EMFs may have biological effects, such as changes in oxidative metabolism after exposure. Therefore, we have investigated the effect of acute UHF-EMF exposure on non-enzymatic antioxidant defense and lipid and protein oxidative damage in the rat frontal cortex and hippocampus. We have used malondialdehyde (MDA) and carbonyl assays to assess lipid and protein oxidative damages, respectively. No changes in lipid and protein damage, and also in non-enzymatic defense were found in frontal cortex or hippocampus. These results suggest that acute UHF-EMF exposure is not able to produce detectable oxidative stress in rats from any age tested. However, more tests using a longer period of exposure and evaluating other tissues are necessary to ensure that there is no health risk associated with the use of mobile phones.

Recognition memory impairment and brain oxidative stress induced by postnatal iron administration.

Iron accumulation in the brain has been implicated in the pathogenesis of neurodegenerative disorders. It is known that iron catalyses the formation of highly reactive hydroxyl radicals. Recent studies have implicated oxidative damage in memory deficits in rats and humans. The purpose of the present study was to investigate the long-term effects of iron treatment in four different phases of the neonatal period on recognition memory in rats. Additionally, parameters of oxidative stress in cerebral regions related to memory formation were evaluated. Male Wistar rats received vehicle or 10.0 mg/kg of Fe2+ orally at postnatal days 5-7, 12-14, 19-21 or 30-32. Animals given iron at any phase of the neonatal period showed impairments in long-term retention of object recognition memory, although only the group given iron from postnatal days 12-14 showed a complete memory blockade. Iron treatment induced oxidative damage in the brain as assessed by the thiobarbituric acid reactive species assay. Moreover, iron administration increased superoxide production in submitochondrial particles, suggesting impaired mitochondrial function; and there was an increase in superoxide dismutase activity in brain regions susceptible to iron administration. The results show that iron load in the early stages of life induces cognitive impairment possibly by inducing oxidative damage in the brain. These findings are consistent with the view that oxidative stress may be related to the cognitive decline observed in normal ageing.

Effect of protein malnutrition on redox state of the hippocampus of rat.

The protein malnutrition is a worldwide problem, affecting mainly newborns and children of developing countries. This deficiency reaches the brain in the most critical period of the development. Various consequences are related to this insult, such as memory disturbance, learning, and behavioral impairment. Protein content of the diet plays an important role on antioxidant mechanisms. This study observed the effects of protein malnutrition on rat hippocampus redox state. Wistar rats were separate in four groups, receiving different diets: first group with 25% casein, protein deficient group with 8% casein, and the same two groups supplemented with methionine (0.15%). Diets were isocaloric and were administered since the prenatal period up to the sacrifice. Rats were decapitated at 21 or 75 days old and hippocampus were isolated for measuring the lipoperoxidation by TBARS method, protein oxidative damage by carbonyl (DNPH) levels, and the activities of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT). There was significant alterations in the activities of the enzyme SOD, lipoperoxidation, and protein oxidation in hippocampus of 21 and 75 day-old rats fed with 25% of protein with methionine and the groups fed with low levels of protein (8%) both supplemented or not with methionine. Our data suggest that both the content of protein in the diet and the essential amino acid methionine may alter the antioxidant system and the redox state of the brain.

Lung oxidative response after acute coal dust exposure.

Coal dust exposure can induce an acute alveolar and interstitial inflammation that can lead to chronic pulmonary diseases. The objective of this study was to describe the acute and later effects of acute coal dust exposure in lung parenchyma and the involvement of reactive oxygen species in coal dust effects. Forty-eight male Wistar rats (200-250 mg) were separated into four groups: 48 h, 7 days, 30 days, and 60 days after coal dust instillation. Gross mineral coal dust (3 mg/0.5 mL saline) was administered directly in the lungs of the treatment group by intratracheal instillation. Control animals received only saline solution (0.5 mL). Lipid peroxidation was determined by the quantity of thiobarbituric acid-reactive species (TBARS), oxidative damage to protein was obtained by the determination of carbonyl groups, the total radical-trapping antioxidant parameter (TRAP) was estimated by luminol chemoluminescence emission, catalase activity was measured by the rate of decrease in hydrogen peroxide, and superoxide dismutase activity was assayed by the inhibition of adrenaline autooxidation. Histological evaluation of coal dust-treated rats demonstrated an inflammatory infiltration after 48 h of the exposure. Initially, this was a cellular infiltration suggestive of lymphocyte infiltration with lymphoid hyperplasia that remained until 7 days after induction. This initial response was followed by a chronic inflammatory infiltration characterized by aggregates of macrophages 30 days after induction. This inflammatory response tended to resolve 60 days after induction, being similar to that of control animals. During both the acute and chronic phases of lung inflammation we observed a decrease in the TRAP in the lung of coal dust-exposed animals compared to that in control animals. We also observed an activation of superoxide dismutase 60 days after coal dust exposition. TBARS were increased 60 days after coal dust exposure and protein carbonyl groups increased at all times after coal dust exposure (48 h, 7 days, 30 days, and 60 days). These data suggested a biphasic inflammatory response and the involvement of oxidative damage in coal dust-induced lung damage.

No evidence for oxidative damage in the hippocampus after acute and chronic electroshock in rats.

Although several advances has occurred over the past 20 years concerning the use of electroconvulsive therapy (ECT), little progress has been made in the mechanisms underlying its therapeutic or adverse effects. Thus, this work was performed in order to determine the level of oxidative damage and antioxidant enzyme activities early and late after acute and chronic electroconvulsive shock (ECS). We demonstrated a decrease in lipid peroxidation in the hippocampus immediately after and up to 30 days after a single or multiple electroconvulsive shock. This was also true for protein carbonyls in the acute protocol. We demonstrated an increase in catalase (CAT) and superoxide dismutase (SOD) activities at different time points after single and multiple electroconvulsive shock. Our findings, for the first time, demonstrated that after electroconvulsive shock, there is an increase in antioxidant enzyme activities and we cannot demonstrate oxidative damage in the hippocampus.

Oxidative damage in brains of mice treated with apomorphine and its oxidized derivative.

Increasing evidence suggests that some of the neurobiological and neurotoxic actions of apomorphine and other dopamine receptor agonists might be mediated by their oxidation derivatives. The aim of the present study was to evaluate the effects of apomorphine and its oxidation derivative, 8-oxo-apomorphine-semiquinone (8-OASQ), on oxidative stress parameters and antioxidant enzyme activity. Adult male CF-1 mice were treated with a systemic injection of apomorphine (0.4, 4.0 or 40.0 mg/kg) or 8-OASQ (0.4, 4.0 or 40.0 mg/kg). Animals were sacrificed by decapitation 24 h after treatment, and the forebrains were collected for analysis of thiobarbituric acid reactive species, protein carbonyls, the total radical-trapping antioxidant parameter, catalase and superoxide dismutase. These treatments did not induce lipid peroxidation at any dose tested. In contrast, apomorphine induced an increase in protein carbonylation and a decrease in total radical-trapping antioxidant parameter at all doses tested. 8-OASQ induced an increase in protein carbonylation and a decrease in total radical-trapping antioxidant parameter only at the higher dose tested. All apomorphine doses tested induced an increase in catalase, but not superoxide dismutase activities. In contrast, 8-OASQ induced a dose-dependent increase in CAT activity. The results suggest that apomorphine and its oxidation product, 8-OASQ, induce differential effects on CNS oxidative parameters.

Oxidative parameters and mortality in sepsis induced by cecal ligation and perforation.

OBJECTIVE: This study assessed parameters of free radical damage to biomolecules, mitochondrial superoxide production, superoxide dismutase, and catalase activities and their relationship to sepsis mortality. DESIGN AND SETTING: Prospective animal study in a university laboratory for experimental. SUBJECTS: 140 male Wistar rats. INTERVENTIONS: The animals were randomly divided into three groups: sham-operated (n=20), cecal ligation and perforation resuscitated with normal saline (n=40), and cecal ligation and perforation with normal saline plus antibiotics (n=40). MEASUREMENTS AND RESULTS: Blood samples were collected from all animals 3, 12, and 24 h after CLP through a jugular catheter inserted before CLP. Rats were evaluated during 5 days after the intervention. Nonsurvivor animals were grouped according to the duration between sepsis induction and death, and oxidative parameters were compared to survivors and sham-operated. Lipid peroxidation, protein carbonyls, and superoxide dismutase were significantly increased in nonsurvivor septic rats and were predictive of mortality. We demonstrated that there is a different modulation of superoxide dismutase and catalase in nonsurvivors during the course of septic response. There was a marked increase in superoxide dismutase activity without a proportional increase in catalase activity in nonsurvivors. CONCLUSIONS: This is the first report of plasma superoxide dismutase as an earlier marker of mortality. Ours results might help to clarify an important aspect of oxidative response to sepsis, i.e., an increase in superoxide dismutase activity without a proportional increase in catalase activity