Loneliness, social support and cardiovascular reactivity to laboratory stress

Self-reported or explicit loneliness and social support have been inconsistently associated with cardiovascular reactivity (CVR) to stress. The present study aimed to adapt an implicit measure of loneliness, and use it alongside the measures of explicit loneliness and social support, to investigate their correlations with CVR to laboratory stress. Twenty-five female volunteers aged between 18 and 39 years completed self-reported measures of loneliness and social support, and an Implicit Association Test (IAT) of loneliness. The systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) reactivity indices were measured in response to psychosocial stress induced in the laboratory. Functional support indices of social support were significantly correlated with CVR reactivity to stress. Interestingly, implicit, but not explicit, loneliness was significantly correlated with DBP reactivity after one of the stressors. No associations were found between structural support and CVR indices. Results are discussed in terms of validity of implicit versus explicit measures and possible factors that affect physiological outcomes

Mood and transient cardiac dysfunction in everyday life

Emotion in daily life may be associated with transient myocardial ischemia, ventricular tachycardia and impaired autonomic function in cardiac patients, but the precise temporal sequence is unclear. Eighty-eight patients with suspected coronary artery disease underwent 24-h electrocardiographic monitoring, and affect was measured with the Day Reconstruction Method. Thirteen patients (15%) experienced one or more episodes of ST depression or ventricular tachycardia, nine of whom provided concurrent mood data. Mood and heart rate variability were analyzed for the 15 min before, during, and 15 min after each ST depression/ventricular tachycardia episode, and were compared with control periods not associated with cardiac dysfunction. Patients reported more negative mood in the 15 min preceding cardiac dysfunction compared with control periods (P = 0.02). Heart rate increased in the 5 min before cardiac dysfunction (P = 0.005), whereas low frequency heart rate variability was reduced at onset but not before cardiac dysfunction (P = 0.007). There were not changes in high frequency heart rate variability. This small study indicates that emotional state may contribute to vulnerability of cardiac dysfunction in everyday life

Cardiac oxygen supply is compromised during the night in hypertensive patients

The enhanced heart rate and blood pressure soon after awaking increases cardiac oxygen demand, and has been associated with the high incidence of acute myocardial infarction in the morning. The behavior of cardiac oxygen supply is unknown. We hypothesized that oxygen supply decreases in the morning and to that purpose investigated cardiac oxygen demand and oxygen supply at night and after awaking. We compared hypertensive to normotensive subjects and furthermore assessed whether pressures measured non-invasively and intra-arterially give similar results. Aortic pressure was reconstructed from 24-h intra-brachial and simultaneously obtained non-invasive finger pressure in 14 hypertensives and 8 normotensives. Supply was assessed by Diastolic Time Fraction (DTF, ratio of diastolic and heart period), demand by Rate-Pressure Product (RPP, systolic pressure times heart rate, HR) and supply/demand ratio by Adia/Asys, with Adia and Asys diastolic and systolic areas under the aortic pressure curve. Hypertensives had lower supply by DTF and higher demand by RPP than normotensives during the night. DTF decreased and RPP increased in both groups after awaking. The DTF of hypertensives decreased less becoming similar to the DTF of normotensives in the morning; the RPP remained higher. Adia/Asys followed the pattern of DTF. Findings from invasively and non-invasively determined pressure were similar. The cardiac oxygen supply/demand ratio in hypertensive patients is lower than in normotensives at night. With a smaller night-day differences, the hypertensives’ risk for cardiovascular events may be more evenly spread over the 24 h. This information can be obtained noninvasively

Mite species inhabiting commercial bumblebee (Bombus terrestris) nests in Polish greenhouses

Nests of social insects are usually inhabited by various mite species that feed on pollen, other micro-arthropods or are parasitic. Well-known negative effects of worldwide economic importance are caused by mites parasitizing honeybee colonies. Lately, attention has focused on the endoparasitic mite Locustacarus buchneri that has been found in commercial bumblebees. However, little is known of other mites associated with commercial bumblebee nests. Transportation of commercial bumblebee colonies with unwanted residents may introduce foreign mite species to new localities. In this study, we assessed the prevalence and species composition of mites associated with commercial bumblebee nests and determined if the mites are foreign species for Poland and for Europe. The study was conducted on 37 commercial bumblebee nests from two companies (Dutch and Israeli), originating from two greenhouses in southern Poland, and on 20 commercial bumblebee colonies obtained directly from suppliers. The species composition and abundance of mites inhabiting commercial bumblebee nests were determined. Seven mite species from three families were found in nests after greenhouse exploitation. The predominant mite species was Tyrophagus putrescentiae (Acaridae) that was a 100-fold more numerous than representatives of the family Laelapidae (Hypoaspis marginepilosa, H. hyatti, H. bombicolens). Representatives of Parasitidae (Parasitellus fucorum, P. crinitus, P. ignotus) were least numerous. All identified mite species are common throughout Europe, foreign species were not found. Mites were not detected in nests obtained directly from suppliers. We conclude that probably bumblebee nests are invaded by local mite species during greenhouse exploitation

The rise of consumer health wearables: promises and barriers

Will consumer wearable technology ever be adopted or accepted by the medical community? Patients and practitioners regularly use digital technology (e.g., thermometers and glucose monitors) to identify and discuss symptoms. In addition, a third of general practitioners in the United Kingdom report that patients arrive with suggestions for treatment based on online search results. However, consumer health wearables are predicted to become the next “Dr Google.” One in six (15%) consumers in the United States currently uses wearable technology, including smartwatches or fitness bands. While 19 million fitness devices are likely to be sold this year, that number is predicted to grow to 110 million in 2018. As the line between consumer health wearables and medical devices begins to blur, it is now possible for a single wearable device to monitor a range of medical risk factors. Potentially, these devices could give patients direct access to personal analytics that can contribute to their health, facilitate preventive care, and aid in the management of ongoing illness. However, how this new wearable technology might best serve medicine remains unclea

Viewing Loved Faces Inhibits Defense Reactions: A Health-Promotion Mechanism?

We have known for decades that social support is associated with positive health outcomes. And yet, the neurophysiological mechanisms underlying this association remain poorly understood. The link between social support and positive health outcomes is likely to depend on the neurophysiological regulatory mechanisms underlying reward and defensive reactions. The present study examines the hypothesis that emotional social support (love) provides safety cues that activate the appetitive reward system and simultaneously inhibit defense reactions. Using the startle probe paradigm, 54 undergraduate students (24 men) viewed black and white photographs of loved (romantic partner, father, mother, and best friend), neutral (unknown), and unpleasant (mutilated) faces. Eye–blink startle, zygomatic major activity, heart rate, and skin conductance responses to the faces, together with subjective ratings of valence, arousal, and dominance, were obtained. Viewing loved faces induced a marked inhibition of the eye-blink startle response accompanied by a pattern of zygomatic, heart rate, skin conductance, and subjective changes indicative of an intense positive emotional response. Effects were similar for men and women, but the startle inhibition and the zygomatic response were larger in female participants. A comparison between the faces of the romantic partner and the parent who shares the partner’s gender further suggests that this effect is not attributable to familiarity or arousal. We conclude that this inhibitory capacity may contribute to the health benefits associated with social support.This research was funded by grant P07-SEJ-02964 from Junta de Andalucía (Spain)

Rural-Urban Differences in Maternal Responses to Childhood Fever in South East Nigeria

Childhood fevers due to malaria remain a major cause of morbidity and mortality among under-five children in Nigeria. The degree of vulnerability perceived by mothers will affect their perception of the severity and threat of their child's fever and the patterns of health care use. This study was undertaken to compare maternal responses to childhood fever in urban and rural areas of Enugu, south east Nigeria.Data was collected with pre-tested interviewer-administered questionnaires from 276 and 124 urban and rural households respectively. In each household, only one woman aged 15-49 years who had lived in each of the urban and rural communities for at least one year and had at least one child less than 5 years old was interviewed. Malaria was mentioned as the commonest cause of childhood fevers. Rural mothers were more likely to recognize danger signs and symptoms than urban mothers. Rural mothers use more of informal than formal health services, and there is more home management of the fever with urban than rural mothers. Chloroquine, ACT, SP and Paracetamol are the main drugs given at home for childhood fevers, but the rural mothers were more likely to use leftover drugs from previous treatment to treat the fevers than urban mothers. The urban respondents were also more likely to use a preventive measure. Urban mothers sought actions faster than rural mothers and the total cost of treatment was also higher in urban areas.Both urban and rural mothers are aware that malaria is the major cause of childhood fevers. Although rural mothers recognize childhood fever and danger signs better than urban mothers, the urban mothers' responses to fever seem to be better than that for rural mothers. These responses and differences may be important for geographical targeting by policy makers for malaria interventions

Impact of voluntary exercise and housing conditions on hippocampal glucocorticoid receptor, miR-124 and anxiety

Background: Lack of physical activity and increased levels of stress contribute to the development of multiple physical and mental disorders. An increasing number of studies relate voluntary exercise with greater resilience to psychological stress, a process that is highly regulated by the hypothalamic-pituitary-adrenal (HPA) axis. However, the molecular mechanisms underlying the beneficial effects of exercise on stress resilience are still poorly understood. Here we have studied the impact of long term exercise and housing conditions on: a) hippocampal expression of glucocorticoid receptor (Nr3c1), b) epigenetic regulation of Nr3c1 (DNA methylation at the Nr3c1-1F promoter and miR-124 expression), c) anxiety (elevated plus maze, EPM), and d) adrenal gland weight and adrenocorticotropic hormone receptor (Mc2r) expression. Results: Exercise increased Nr3c1 and Nr3c1-1F expression and decreased miR-124 levels in the hippocampus in single-housed mice, suggesting enhanced resilience to stress. The opposite was found for pair-housed animals. Bisulfite sequencing showed virtually no DNA methylation in the Nr3c1-1F promoter region. Single-housing increased the time spent on stretch attend postures. Exercise decreased the time spent at the open arms of the EPM, however, the mobility of the exercise groups was significantly lower. Exercise had opposite effects on the adrenal gland weight of single and pair-housed mice, while it had no effect on adrenal Mc2r expression. Conclusions: These results suggest that exercise exerts a positive impact on stress resilience in single-housed mice that could be mediated by decreasing miR-124 and increasing Nr3c1 expression in the hippocampus. However, pair-housing reverses these effects possibly due to stress from dominance disputes between pairs