Avaliação dos efeitos da adição de sal e da densidade no transporte de tambaqui

Os objetivos deste trabalho foram testar a eficiência do sal como redutor de estresse e verificar a melhor densidade de transporte de juvenis de tambaqui (Colossoma macropomun) em caixas de plástico adaptadas. No primeiro experimento foram testadas diferentes concentrações de sal de cozinha (NaCl) na água; no segundo, o transporte foi realizado por três horas em caixas de plástico de 200 L estocadas com diferentes densidades de peixe, com 8 g de sal/L de água. O cortisol plasmático dos peixes sofreu aumento significativo após o transporte no tratamento sem sal e com 2 g de sal/L de água, retornando para níveis normais após 96 horas. A glicose plasmática dos peixes sofreu aumento após o transporte em todas as concentrações de sal testadas, com exceção da com 8 g/L de água, retornando para níveis normais em 24 horas. Nos peixes transportados no segundo experimento, com 8 g de sal/L de água, não foi verificada mudança significativa no cortisol plasmático, mas a glicose aumentou significativamente em todas as densidades após o transporte, retornando para níveis normais em 24 horas. Houve mortalidade de 11% em uma das repetições da densidade de 200 kg/m³ de água. Para o transporte com 8 g de sal/L de água, a densidade máxima deve ser de 150 kg/m³ de água. Nesta densidade os parâmetros físico-químicos de qualidade de água se mantêm com características adequadas, as respostas ao estresse são mínimas e não há mortalidade.

Biological indicators of stress in pacu (Piaractus mesopotamicus) after capture

Os efeitos da captura (perseguição, contenção em puçá e exposição aérea) no perfil sanguíneo do cortisol, glicose, cloreto, sódio, potássio, cálcio e na osmolaridade, hematócrito, hemoglobina, número de células vermelhas (CV) e volume corpuscular médio (VCM) foram investigados no pacu (Piaractus mesopotamicus). Um total de 132 peixes (49,7 ± 11,7 g) foi submetido à captura com 3 ou 5 minutos de exposição aérea. Nove peixes de cada tratamento foram amostrados 5, 15, 30, 60 minutos e 24 horas depois e outros nove peixes foram amostrados antes da captura e considerados controle. A captura resultou em aumento do cortisol e glicose no sangue 30 e 5 minutos depois da captura, respectivamente, independente do tempo de exposição aérea. Ambos os indicadores recuperaram os valores controle em 24 horas. Nos dois grupos de peixes, o cloreto plasmático diminuiu 60 minutos após captura e não recuperou os valores controle, enquanto o sódio sérico aumentou entre 15 e 30 minutos recuperando a condição controle em 24 horas. Não houve alteração significativa nos valores de potássio, cálcio, osmolaridade ou no hematócrito, hemoglobina, CV e VCM como consequência da captura. Os estressores sequenciais aplicados no pacu durante a captura ativaram o eixo cérebro-pituitária-interrenal (respostas do cortisol e glicose), mas a ativação do eixo cérebro-sistema simpático-células cromafins foi aparentemente moderada (respostas iônicas e hematológicas).

Caracterização clínica, metabólica e hormonal de portadores de lipodistrofia parcial familiar

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Programa de Pós-Graduação em Ciências da Saúde, 2015.

Transport of Pirarucu Arapaima gigas juveniles in plastic bag

Este estudo examinou as respostas de estresse de juvenis de pirarucu transportados em sistema fechado. Pirarucu (Arapaima gigas) é um peixe nativo da bacia Amazônica, da família Osteoglossidae que possui respiração aérea obrigatória. Foi realizado um transporte de curta duração (6 h) em sacos de polietileno inflados com ar atmosférico (grupo ar) ou com oxigênio puro (grupo oxi). O oxigênio dissolvido foi o único parâmetro de qualidade da água que apresentou diferença estatística entre os grupos, e como esperado, o oxigênio estava supersaturado para o grupo oxi. Não houve mortalidade após o transporte em ambos os grupos. Os peixes se alimentaram 36 h após o transporte e apresentaram um consumo de ração habitual após 72 h. As respostas fisiológicas foram semelhantes nos dois grupos. O cortisol não apresentou mudança significativa durante o período de amostragem. Ao contrário da maioria das espécies, os valores de cortisol se apresentaram inalterados nos dois grupos durante a amostragem, enquanto a glicose teve um aumento significativo até 12 h após o transporte. Os resultados mostram que o transporte de pirarucu em sacos de polietileno pode ser realizado com ar atmosférico ou oxigênio puro, uma vez que as respostas de estresse, a qualidade da água e o comportamento alimentar após 36 h foram similar entre os grupos.

Stress in pacu exposed to ammonia in water

The present study evaluated stress indicators in pacu exposed to ammonia in water under the following conditions: without NH4Cl (0.00 g/L); with 0.0078 g NH4Cl/L; and with 0.078 g NH4Cl/L (pH 8.3 and 27 ºC). After the salt dilution the water flow was interrupted and reestablished in 24 hours. Sampling occurred prior to the addition of NH4Cl (control) and after 12, 24 and 48 hours. Glycaemia increased only in fish with the highest salt concentration when compared with group control, regardless of time, and at 24 hours, regardless of treatment. Plasma ammonia, highest in fish exposed to the highest NH4Cl concentration, decreased progressively up to 48 hours. Plasma chloride only decreased in fish not exposed to salt when compared with control and osmolality increased after 24 hours. Hematocrit (Ht), number and volume of erythrocytes and hemoglobin did not change when NH4Cl was added; Ht decrease was reported after 12 hours, but it was not followed by the other blood parameters. The results show tolerance of the pacu to ammonia in the environment.

Effects of exercise on the desire to smoke and physiological responses to temporary smoking abstinence: a crossover trial

RATIONALE: Exercise has been shown to attenuate cigarette cravings during temporary smoking abstinence; however, the mechanisms of action are not clearly understood. OBJECTIVES: The objectives of the study were to compare the effects of three exercise intensities on desire to smoke and explore potential neurobiological mediators of desire to smoke. METHODS: Following overnight abstinence, 40 participants (25 males, 18-59 years) completed three 15 min sessions of light-, moderate-, or vigorous-intensity exercise on a cycle ergometer in a randomized crossover design. Ratings of desire to smoke were self-reported pre- and post-exercise and heart rate variability was measured throughout. Saliva and blood were analyzed for cortisol and noradrenaline in a sub-sample. RESULTS: Exercise influenced desire to smoke (F [2, 91] = 7.94, p < 0.01), with reductions greatest immediately after vigorous exercise. There were also significant time x exercise intensity interaction effects for heart rate variability and plasma noradrenaline (F [8, 72] = 2.23, p = 0.03), with a bias in noradrenaline occurring between light and vigorous conditions (adjusted mean difference [SE] = 2850 ng/ml [592], p < 0.01) at 5 min post-exercise. There was no interaction of time x exercise intensity for plasma and salivary cortisol levels. CONCLUSIONS: These findings support the use of vigorous exercise to reduce cigarette cravings, showing potential alterations in a noradrenergic marker.

Bias in emerging biomarkers for bipolar disorder

BACKGROUND: To date no comprehensive evaluation has appraised the likelihood of bias or the strength of the evidence of peripheral biomarkers for bipolar disorder (BD). Here we performed an umbrella review of meta-analyses of peripheral non-genetic biomarkers for BD. METHOD: The Pubmed/Medline, EMBASE and PsycInfo electronic databases were searched up to May 2015. Two independent authors conducted searches, examined references for eligibility, and extracted data. Meta-analyses in any language examining peripheral non-genetic biomarkers in participants with BD (across different mood states) compared to unaffected controls were included. RESULTS: Six references, which examined 13 biomarkers across 20 meta-analyses (5474 BD cases and 4823 healthy controls) met inclusion criteria. Evidence for excess of significance bias (i.e. bias favoring publication of 'positive' nominally significant results) was observed in 11 meta-analyses. Heterogeneity was high for (I 2 ⩾ 50%) 16 meta-analyses. Only two biomarkers met criteria for suggestive evidence namely the soluble IL-2 receptor and morning cortisol. The median power of included studies, using the effect size of the largest dataset as the plausible true effect size of each meta-analysis, was 15.3%. CONCLUSIONS: Our findings suggest that there is an excess of statistically significant results in the literature of peripheral biomarkers for BD. Selective publication of 'positive' results and selective reporting of outcomes are possible mechanisms.

One size does not fit all : monitoring faecal glucocorticoid metabolites in marsupials

Marsupial research, conservation, and management can benefit greatly from knowledge about glucocorticoid (GC) secretion patterns because GCs influence numerous aspects of physiology and play a crucial role in regulating an animal's response to stressors. Faecal glucocorticoid metabolites (FGM) offer a non-invasive tool for tracking changes in GCs over time. To date, there are relatively few validated assays for marsupials compared with other taxa, and those that have been published generally test only one assay. However, different assays can yield very different signals of adrenal activity. The goal of this study was to compare the performance of five different enzyme immunoassays (EIAs) for monitoring adrenocortical activity via FGM in 13 marsupial species. We monitored FGM response to two types of events: biological stressors (e.g., transport, novel environment) and pharmacological stimulation (ACTH injection). For each individual animal and assay, FGM peaks were identified using the iterative baseline approach. Performance of the EIAs for each species was evaluated by determining (1) the percent of individuals with a detectable peak 0.125-4.5days post-event, and (2) the biological sensitivity of the assay as measured by strength of the post-event response relative to baseline variability (Z-score). Assays were defined as successful if they detected a peak in at least 50% of the individuals and the mean species response had a Z⩾2. By this criterion, at least one assay was successful in 10 of the 13 species, but the best-performing assay varied among species, even those species that were closely related. Furthermore, the ability to confidently assess assay performance was influenced by the experimental protocols used. We discuss the implications of our findings for biological validation studies.

Bifidobacterium longum 1714 as a translational psychobiotic: modulation of stress, electrophysiology and neurocognition in healthy volunteers

The emerging concept of psychobiotics—live microorganisms with a potential mental health benefit—represents a novel approach for the management of stress-related conditions. The majority of studies have focused on animal models. Recent preclinical studies have identified the B. longum 1714 strain as a putative psychobiotic with an impact on stress-related behaviors, physiology and cognitive performance. Whether such preclinical effects could be translated to healthy human volunteers remains unknown. We tested whether psychobiotic consumption could affect the stress response, cognition and brain activity patterns. In a within-participants design, healthy volunteers (N=22) completed cognitive assessments, resting electroencephalography and were exposed to a socially evaluated cold pressor test at baseline, post-placebo and post-psychobiotic. Increases in cortisol output and subjective anxiety in response to the socially evaluated cold pressor test were attenuated. Furthermore, daily reported stress was reduced by psychobiotic consumption. We also observed subtle improvements in hippocampus-dependent visuospatial memory performance, as well as enhanced frontal midline electroencephalographic mobility following psychobiotic consumption. These subtle but clear benefits are in line with the predicted impact from preclinical screening platforms. Our results indicate that consumption of B. longum 1714 is associated with reduced stress and improved memory. Further studies are warranted to evaluate the benefits of this putative psychobiotic in relevant stress-related conditions and to unravel the mechanisms underlying such effects.

Lost in translation? The potential psychobiotic Lactobacillus rhamnosus (JB-1) fails to modulate stress or cognitive performance in healthy male subjects

Background: Preclinical studies have identified certain probiotics as psychobiotics a live microorganisms with a potential mental health benefit. Lactobacillus rhamnosus (JB-1) has been shown to reduce stress-related behaviour, corticosterone release and alter central expression of GABA receptors in an anxious mouse strain. However, it is unclear if this single putative psychobiotic strain has psychotropic activity in humans. Consequently, we aimed to examine if these promising preclinical findings could be translated to healthy human volunteers. Objectives: To determine the impact of L. rhamnosus on stress-related behaviours, physiology, inflammatory response, cognitive performance and brain activity patterns in healthy male participants. An 8 week, randomized, placebo-controlled, cross-over design was employed. Twenty-nine healthy male volunteers participated. Participants completed self-report stress measures, cognitive assessments and resting electroencephalography (EEG). Plasma IL10, IL1β, IL6, IL8 and TNFα levels and whole blood Toll-like 4 (TLR-4) agonist-induced cytokine release were determined by multiplex ELISA. Salivary cortisol was determined by ELISA and subjective stress measures were assessed before, during and after a socially evaluated cold pressor test (SECPT). Results: There was no overall effect of probiotic treatment on measures of mood, anxiety, stress or sleep quality and no significant effect of probiotic over placebo on subjective stress measures, or the HPA response to the SECPT. Visuospatial memory performance, attention switching, rapid visual information processing, emotion recognition and associated EEG measures did not show improvement over placebo. No significant anti-inflammatory effects were seen as assessed by basal and stimulated cytokine levels. Conclusions: L. rhamnosus was not superior to placebo in modifying stress-related measures, HPA response, inflammation or cognitive performance in healthy male participants. These findings highlight the challenges associated with moving promising preclinical studies, conducted in an anxious mouse strain, to healthy human participants. Future interventional studies investigating the effect of this psychobiotic in populations with stress-related disorders are required.

A systematic review of the psychobiological burden of informal caregiving for patients with dementia: focus on cognitive and biological markers of chronic stress

As the physiological impact of chronic stress is difficult to study in humans, naturalistic stressors are invaluable sources of information in this area. This review systematically evaluates the research literature examining biomarkers of chronic stress, including neurocognition, in informal dementia caregivers. We identified 151 papers for inclusion in the final review, including papers examining differences between caregivers and controls as well as interventions aimed at counteracting the biological burden of chronic caregiving stress. Results indicate that cortisol was increased in caregivers in a majority of studies examining this biomarker. There was mixed evidence for differences in epinephrine, norepinephrine and other cardiovascular markers. There was a high level of heterogeneity in immune system measures. Caregivers performed more poorly on attention and executive functioning tests. There was mixed evidence for memory performance. Interventions to reduce stress improved cognition but had mixed effects on cortisol. Risk of bias was generally low to moderate. Given the rising need for family caregivers worldwide, the implications of these findings can no longer be neglected.

Experience modulates the psychophysiological response of airborne warfighters during a tactical combat parachute jump

We aimed to analyse the effect of experience level in the psychophysiological response and specific fine motor skills of novel and expert parachute warfighters during a tactical combat parachute jump. We analysed blood oxygen saturation, heart rate, salivary cortisol, blood glucose, lactate and creatinkinase, leg strength, isometric hand-grip strength, cortical arousal, specific fine motor skills and cognitive anxiety, somatic anxiety and self-confident before and after a tactical combat parachute jump in 40 warfighters divided in two group, novel (n = 17) and expert group (n = 23). Novels presented a higher heart rate, lactate, cognitive anxiety, somatic anxiety and a lower self-confident than experts during the jump. We concluded that experience level has a direct effect on the psychophysiological response since novel paratroopers presented a higher psychophysiological response than compared to the expert ones, however this result neither affected the specific fine motor skills nor the muscle structure after a tactical combat parachute jump.

The effect of working on-call on stress physiology and sleep: a systematic review

On-call work is becoming an increasingly common work pattern, yet the human impacts of this type of work are not well established. Given the likelihood of calls to occur outside regular work hours, it is important to consider the potential impact of working on-call on stress physiology and sleep. The aims of this review were to collate and evaluate evidence on the effects of working on-call from home on stress physiology and sleep. A systematic search of Ebsco Host, Embase, Web of Science, Scopus and ScienceDirect was conducted. Search terms included: on-call, on call, standby, sleep, cortisol, heart rate, adrenaline, noradrenaline, nor-adrenaline, epinephrine, norepinephrine, nor-epinephrine, salivary alpha amylase and alpha amylase. Eight studies met the inclusion criteria, with only one study investigating the effect of working on-call from home on stress physiology. All eight studies investigated the effect of working on-call from home on sleep. Working on-call from home appears to adversely affect sleep quantity, and in most cases, sleep quality. However, studies did not differentiate between night's on-call from home with and without calls. Data examining the effect of working on-call from home on stress physiology were not sufficient to draw meaningful conclusions.

Asociación de las violencias física, sexual y comunitaria con el embarazo en adolescentes: análisis multinivel

Objetivos Determinar si existe asociación entre la exposición a violencia, experimentada a nivel individual o municipal, y el embarazo adolescente en mujeres Colombianas entre 13 y 19 años de edad que contestaron la Encuesta de Demografía y Salud en el año 2010. Métodos Estudio de corte transversal, nacional y multinivel. Se tomaron datos de dos niveles jerárquicos: Nivel- 1: Datos individuales de una muestra representativa de 13.313 mujeres entre 13 y 19 años de edad provenientes de La Encuesta Nacional de Demografía y Salud del año 2010 y Nivel- 2: Datos municipales de 258 municipios provenientes de las estadísticas vitales del DANE. Resultados La prevalencia del embarazo adolescente fue del 16.8% IC 95% [16.2-17.4]. El análisis mostró que la asociación entre embarazo adolescente y violencia tanto individual, representada como violencia sexual [OR= 6.99 IC99% 4.80-10.10] y violencia física [OR= 1.74 IC99% 1.47-2.05] así como la violencia municipal medida con tasas de homicidios altas [OR= 1.99 IC99% 1.29-3.07] y muy altas [OR= 2.10 IC99% 1.21-3.61] se mantuvo estadísticamente significativa después de ajustar por las variables: Edad [OR= 1.81 IC99% 1.71-1.91], ocupación [OR= 1.62 IC99% 1.37-1.93], educación primaria o sin educación [OR= 2.20 IC99% 1.47-3.30], educación secundaria [OR= 1.70 IC99% 1.24-2.32], asistir al colegio [OR= 0.18 IC99% 0.15-0.21], conocimiento en la fisiología reproductiva [OR= 1.28 IC99% 1.06-1.54], el índice de riqueza Q1, Q2, Q3 [OR= 2.18 IC99% 1.42-3.34], [OR= 2.00 IC99% 1.39-2.28], [OR= 1.82 IC99% 1.92-2.25] y alto porcentaje de Necesidades básicas insatisfechas a nivel municipal [OR= 2.34 IC99% 1.55-3.52]. Conclusiones Este estudio mostró una relación significativamente estadística entre la violencia sexual y física con el inicio de relaciones sexuales y embarazo adolescente después de controlar por factores sociodemográficos y conocimientos en reproducción sexual en mujeres colombianas de 13 a 19 años en el año 2010. Esta asociación debe continuar siendo estudiada para lograr optimizar las estrategias de prevención y disminuir la tasa actual de embarazos adolescentes en el país y sus consecuencias.

Estado del arte sobre estrés laboral entre los años 2005 y 2016

El propósito de este estudio es realizar un estado del arte sobre estrés laboral entre los años 2005 y 2016 utilizando artículos publicados en las bases de datos Ebsco, Apa-Psychnet, Proquest, Psycodoc, Pubmed, Redalyc y Scielo las cuales están abaladas por la Universidad del Rosario. Se hallaron en total 2674 artículos utilizando 6 palabras claves como criterios de búsqueda los cuales fueron Estrés Laboral, Estrés ocupacional, Estrés en el Trabajo, Job Stress, Work Stress y Occupational Stress. El instrumento de recolección de información fue una ficha bibliográfica modificada la cual permitió sistematizar los datos de los artículos encontrados en diferentes dimensiones para así poder utilizar los artículos encontrados como unidades de análisis para la investigación. El análisis de los artículos arrojó una diferencia significativa entre el volumen de publicaciones hechas en español versus las hechas en inglés tanto de artículos empíricos como teóricos. También se encontraron indicadores que permiten ver como el estudio del estrés laboral ha aumentado desde el año 2012 hasta la actualidad, siendo este el lapso en el cual el 59% de los artículos han sido arbitrados y subidos a las diferentes bases de datos.