Bidirectional Effects Research Articles

Appraising the Associations Between Systemic Iron Status and Epigenetic Clocks: A Genetic Correlation and Bidirectional Mendelian Randomization Study

BackgroundGenetic correlations (Rg) and bidirectional causal effects between systemic iron status and epigenetic clocks have not been fully investigated, although observational studies have suggested systemic iron status is associated with human aging. ObjectivesWe explored the genetic correlations and bidirectional causal effects between systemic iron status and epigenetic clocks. MethodsLeveraging large-scale genome-wide association study summary-level statistics for 4 systemic iron status biomarkers (ferritin, serum iron, transferrin, and transferrin saturation) (N = 48,972) and 4 measures for epigenetic age (GrimAge, PhenoAge, intrinsic epigenetic age acceleration (IEAA), and HannumAge) (N = 34,710), genetic correlations, and bidirectional causal effects were estimated between them mainly by applying linkage disequilibrium score (LDSC) regression, Mendelian randomization (MR), and MR based on Bayesian model averaging. The main analyses were conducted employing multiplicative random-effects inverse-variance weighted MR. MR-Egger, weighted median, weighted mode, and MR-PRESSO were performed as sensitivity analyses to support the robustness of causal effects. ResultsThe LDSC results illustrated Rg between serum iron and PhenoAge (Rg = 0.1971, P = 0.048) and between transferrin saturation and PhenoAge (Rg = 0.196, P = 0.0469). We found that increased ferritin and transferrin saturation significantly increased all 4 measures of epigenetic age acceleration (all P < 0.0125, β > 0). Each standard deviation genetically increases in serum iron only significantly associated with increased IEAA (β: 0.36; 95% CI: 0.16, 0.57; P = 6.01 × 10−4) and increased HannumAge acceleration (β: 0.32; 95% CI: 0.11, 0.52; P = 2.69 × 10−3). Evidence showed a suggestively significant causal effect of transferrin on epigenetic age acceleration (all 0.0125 <P < 0.05). Additionally, reverse MR study indicated no significant causal effect of epigenetic clocks on systemic iron status. ConclusionsAll 4 iron status biomarkers had a significant or suggestively significant causal effect on epigenetic clocks, whereas reverse MR studies did not.

Impact of Body Composition on Sleep and Its Relationship with Sleep Disorders: Current Insights.

Sleep is involved in many physiological processes and is essential for both physical and mental health. Obesity and sleep deprivation due to sleep disorders are major public health issues. Their incidence is increasing, and they have a wide range of adverse health-related consequences, including life-threatening cardiovascular disease. The impact of sleep on obesity and body composition is well-known, and many studies have shown an association between insufficient or excessive sleep duration and obesity, body fat percentage, and weight gain. However, there is growing evidence of the effects of body composition on sleep and sleep disorders (particularly sleep disordered breathing) through anatomical and physiological mechanisms (nocturnal fluid shift, core body temperature, or diet). Although some research has been conducted on the bidirectional effects of sleep-disordered breathing and body composition, the specific effects of obesity and body composition on sleep and the underlying mechanisms that explain these effects remain unclear. Therefore, this review summarizes the findings on the effects of body composition on sleep and draws conclusions and proposals for future research in this field.

The bidirectional effects of antisocial behavior, anxiety, and trauma exposure: Implications for our understanding of the development of callous–unemotional traits.

The association of anxiety and trauma with antisocial behavior in children and adolescents has long been the focus of research, and more recently this area of research has become critical to theories of the development of callous-unemotional (CU) traits. Research suggests those with elevated CU traits and anxiety (i.e., secondary CU variant) seem to show more severe externalizing behaviors and are more likely to show histories of trauma, compared to those with elevated CU and low anxiety (i.e., primary CU variant). These findings have typically been interpreted as being indicative of distinct etiological pathways to the development of CU traits. We test an alternative explanation that the higher rates of anxiety and trauma exposure in some youth with elevated CU traits are largely a consequence of their higher levels of antisocial behavior. The current study recruited a sample of 1,216 justice-involved adolescents (Mage = 15.28, SD = 1.28) from three distinct regions of the United States, who were assessed at 6, 12, 18, 24, 30, 36, 48, and 60 months following their first arrest. Using random-intercept cross-lagged models, both antisocial behavior and CU traits predicted changes in future anxiety and CU traits predicted increases in future victimization. Further, using longitudinal parallel mediation models, antisocial and aggressive behavior largely accounted for the predictive association between CU traits and anxiety and CU traits and victimization. These results support a model in which anxiety and trauma histories may be a marker of the severity of antisocial behavior displayed by youth with elevated CU traits. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Bidirectional effects of parental and adolescent symptom change in trauma-focused cognitive behavioral therapy.

The current study examines dynamic, bidirectional associations between parent and adolescent symptom improvement in response to children's therapy for posttraumatic stress disorder (PTSD). Data were collected from a racially and ethnically heterogeneous sample of 1,807 adolescents (age 13-18 years old; 69% female) and a parent participating in Trauma-Focused Cognitive Behavioral Therapy (TF-CBT) at a community outpatient behavioral health clinic. Parents self-reported their depressive symptoms and youth self-reported their PTSD and depressive symptoms at the onset of treatment and every three months for up to nine months. Using a bivariate dual change score model (BDCSM) we examine: (a) individual dyad members' change in symptoms and (b) the bidirectional associations between changes in the parent's and youth's symptoms across treatment. Parents' and adolescents' symptoms at the start of treatment were correlated and both parents' and adolescents' symptoms decreased over the course of treatment. Parents' elevated depressive symptoms at each time point contributed to smaller decreases in their children's PTSD and depressive symptoms at the subsequent time point. Adolescents' elevated symptoms at each time point contributed to greater decreases in their parents' symptoms at the subsequent time point. These findings highlight the impact that parents and children have on each other's response to children's trauma-focused psychotherapy. Notably, parents' depressive symptoms appeared to slow their children's progress in treatment, suggesting that attending to parents' symptoms and providing them with supportive services may be an important adjunct to children's interventions. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Longitudinal effects of subjective aging on health and longevity: An updated meta-analysis.

This article updates and extends an earlier meta-analysis (Westerhof et al., 2014) on the longitudinal effects of subjective aging (SA) on health outcomes. A systematic search in different databases (APA PsycInfo, PubMed, Web of Science, and Scopus) resulted in 99 articles, reporting on 107 studies. Participants: Studies had a median sample size of 1,863 adults with a median age of 66 years. A randomized effect meta-analysis showed a significant, small effect (likelihood ratio = 1.347; 95% confidence interval [1.300, 1.396]; p < .001), similar in magnitude to the previous meta-analysis of 19 studies. Although the results showed high heterogeneity in the longitudinal link between SA and health outcomes, there were no differences in effects according to chronological age of participants, welfare state status (more or less developed social security system), length of follow-up, type of health-related outcome, or quality of the study. Effects were stronger for multiitem measures of self-perceptions of aging than for the frequently used single-item measures assessing subjective age, especially for indicators of physical health. Based on this meta-analysis, building on five times more studies than the 2014 review, we consider the associations of measures of SA with health and longevity across time as robust, albeit small in size. Future research should concentrate on the clarification of pathways mediating the relation between SA and health outcomes, as well as potential bidirectional effects. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Understanding the relationship between loneliness, substance use traits and psychiatric disorders: A genetically informed approach

Loneliness is a common, yet distressing experience associated with adverse outcomes including substance use problems and psychiatric disorders. To what extent these associations reflect genetic correlations and causal relationships is currently unclear. We applied Genomic Structural Equation Modelling (GSEM) to dissect the genetic architecture between loneliness and psychiatric-behavioural traits. Included were summary statistics from 12 genome-wide association analyses, including loneliness and 11 psychiatric phenotypes (range N: 9,537 – 807,553). We first modelled latent genetic factors amongst the psychiatric traits to then investigate potential causal effects between loneliness and the identified latent factors, using multivariate genome-wide association analyses and bidirectional Mendelian randomization. We identified three latent genetic factors, encompassing neurodevelopmental/mood conditions, substance use traits and disorders with psychotic features. GSEM provided evidence of a unique association between loneliness and the neurodevelopmental/mood conditions latent factor. Mendelian randomization results were suggestive of bidirectional causal effects between loneliness and the neurodevelopmental/mood conditions factor. These results imply that a genetic predisposition to loneliness may elevate the risk of neurodevelopmental/mood conditions, and vice versa. However, results may reflect the difficulty of distiguishing between loneliness and neurodevelopmental/mood conditions, which present in similar ways. We suggest, overall, the importance of addressing loneliness in mental health prevention and policy.

Genome-wide multi-trait analysis of irritable bowel syndrome and related mental conditions identifies 38 new independent variants

BackgroundIrritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction frequently accompanied by mental conditions, including depression and anxiety. Despite showing substantial heritability and being partly determined by a genetic component, the genetic underpinnings explaining the high rates of comorbidity remain largely unclear and there are no conclusive data on the temporal relationship between them. Exploring the overlapping genetic architecture between IBS and mental conditions may help to identify novel genetic loci and biological mechanisms underlying IBS and causal relationships between them.MethodsWe quantified the genetic overlap between IBS, neuroticism, depression and anxiety, conducted a multi-trait genome-wide association study (GWAS) considering these traits and investigated causal relationships between them by using the largest GWAS to date.ResultsIBS showed to be a highly polygenic disorder with extensive genetic sharing with mental conditions. Multi-trait analysis of IBS and neuroticism, depression and anxiety identified 42 genome-wide significant variants for IBS, of which 38 are novel. Fine-mapping risk loci highlighted 289 genes enriched in genes upregulated during early embryonic brain development and gene-sets related with psychiatric, digestive and autoimmune disorders. IBS-associated genes were enriched for target genes of anti-inflammatory and antirheumatic drugs, anesthetics and opioid dependence pharmacological treatment. Mendelian-randomization analysis accounting for correlated pleiotropy identified bidirectional causal effects between IBS and neuroticism and depression and causal effects of the genetic liability of IBS on anxiety.ConclusionsThese findings provide evidence of the polygenic architecture of IBS, identify novel genome-wide significant variants for IBS and extend previous knowledge on the genetic overlap and relationship between gastrointestinal and mental disorders.

Delicious promoter of the restaurant business: measuring impact of supply chain, brand personality and CSR on brand equity development

PurposeThe purpose of this study was to discuss the importance of customer-based brand equity (CBBE) and identify the critical attributes of how to develop CBBE during the most difficult time of the COVID-19 pandemic.Design/methodology/approachThis study collected 386 restaurant managers' viewpoints to examine the mutual relationships among CBBE and other critical attributes of corporate social responsibility (CSR), electronic word of mouth (EWOM) and brand personality. Furthermore, structural equation modeling (SEM) was conducted to examine the proposed moderation and mediation hypotheses.FindingsThe results show that corporate social responsibility (CSR) mediates the relationship between brand personality and brand image. Furthermore, the mutual relationship among CBBE is discovered in that brand image may indirectly affect brand loyalty through perceived quality and brand awareness. Furthermore, with the reliance on social media, the moderating roles of electronic word of mouth (EWOM) are also revealed that strengthen the indirect effect of brand personality on brand awareness through CSR and brand image.Originality/valueWith the increasing attention to CBBE, which aims at tourism destination brand equity, hotel branding from the customer perspective, restaurant managers' viewpoints are not considered. Further, because of the impacts of the COVID-19 pandemic, customers are paying more attention to food safety and food delivery processes, which are important for CSR and connected to CBBE. However, until now, fewer studies have addressed these issues as such. The present study reflects the bidirectional effects of such a comprehensive viewpoint.

Stress deficits in reward behaviour are associated with and replicated by dysregulated amygdala-nucleus accumbens pathway function in mice

Reduced reward interest/learning and reward-to-effort valuation are distinct, common symptoms in neuropsychiatric disorders for which chronic stress is a major aetiological factor. Glutamate neurons in basal amygdala (BA) project to various regions including nucleus accumbens (NAc). The BA-NAc neural pathway is activated by reward and aversion, with many neurons being monovalent. In adult male mice, chronic social stress (CSS) leads to reduced discriminative reward learning (DRL) associated with decreased BA-NAc activity, and to reduced reward-to-effort valuation (REV) associated, in contrast, with increased BA-NAc activity. Chronic tetanus toxin BA-NAc inhibition replicates the CSS-DRL effect and causes a mild REV reduction, whilst chronic DREADDs BA-NAc activation replicates the CSS effect on REV without affecting DRL. This study provides evidence that stress disruption of reward processing involves the BA-NAc neural pathway; the bi-directional effects implicate opposite activity changes in reward (learning) neurons and aversion (effort) neurons in the BA-NAc pathway following chronic stress.

Assessing the pollution level of a subtropical lake by using a novel hydrogen sulfide fluorescence technology

Hydrogen sulfide (H2S) is an important environmental toxin with bi-directional biological effects on organisms. In natural waters, H2S complexes with heavy metal ions in an anaerobic environment influence heavy metals' bioavailability and induce phosphorus release and eutrophication in water columns. Traditional detection techniques, such as colorimetric, electrochemical, and chromatographic, cannot simultaneously detect H2S and pollution assessment of subtropical lakes. To address these technical defects, we developed small-molecule fluorescent probes to evaluate the pollution level in natural water bodies. This method relies on the combination of the probes’ response signals to raw water and the water quality index, thereby enhancing the accuracy and reliability of water quality assessments. Furthermore, this novel material has a large Stokes shift. It can detect complex levels of H2S concentrations in natural water bodies by correlating the degree of contamination and fluorescence signals. The development of this visual research tool for detecting environmental H2S levels in natural water bodies is expected to have meaningful, practical applications.

Identity Formation and General and Cancer-specific Functioning in Adolescent and Emerging Adult Survivors of Childhood Cancer: A Longitudinal Study into Directionality of Effects.

Adolescent and emerging adult survivors of childhood cancer generally adjust well psychologically similar to their peers. Nevertheless, some survivors are at greater risk for developing psychological and physical difficulties. To shed light on the psychosocial functioning of adolescent and emerging adult survivors of childhood cancer, personal identity formation and its interplay with general and cancer-specific functioning need to be investigated. To examine the longitudinal associations linking identity formation to general and cancer-specific functioning in adolescent and emerging adult childhood cancer survivors using three-wave data over a 2-year period. Dutch-speaking survivors (at baseline: n = 125; 53% female; age range: 14-25 years) treated at the pediatric oncology department of the University Hospitals Leuven (Belgium), completed self-report questionnaires at three annual timepoints. Directionality of effects and correlated changes were examined using cross-lagged structural equation modeling. Regarding general functioning, bidirectional effects occurred. Life satisfaction positively predicted identity synthesis and both life satisfaction and good physical functioning negatively predicted identity confusion over time. Identity synthesis, in turn, positively predicted life satisfaction and identity confusion negatively predicted good physical functioning over time. Regarding cancer-specific functioning, mainly unidirectional effects occurred. Post-traumatic stress symptoms negatively predicted identity synthesis and positively predicted identity confusion over time, whereas the reverse pattern of associations was found for benefit finding. Several correlated changes were found linking identity formation and psychosocial functioning as well. The present study uncovered clinically meaningful pathways linking identity formation to psychosocial functioning over time in adolescents and emerging adults who survived childhood cancer.

How Connected is Crude Oil to Stock Sectors Before and After the COVID-19 Outbreak? Evidence from a Novel Network Method

A novel network with Wavelet denoising-GARCHSK and Mixed CoVaR method is proposed to construct full-sample and dynamic networks for investigating the risk spillover effects across international crude oil and Chinese stock sectors before and after the COVID-19 outbreak. The empirical results denote that the total bidirectional oil-sector risk spillover effects increase rapidly after the COVID-19 outbreak. Interestingly, sectors shift from net risk receivers to net risk contributors in the oil-sector risk transfer effects during the pandemic period. Second, unlike the pre-COVID-19 period, Shanghai crude (SC) replaces Brent as the largest oil risk transmitter to stocks during the COVID-19 period. Third, there are notable sectoral features in the oil-sector risk spillovers, which differ across different periods. After the burst, Energy has an incredibly weak connection with crude oil, while the sectors, which oil products are input for, become close with crude oil. Far more surprising is that the petroleum-independent sectors have increasing closer risk transfer effects with crude, even becoming the largest risk contributors to oil, after that. Finally, the oil-sector relationships during the same period are time-varying but stable. This paper provides policymakers and investors with new method and insight into the oil-sector relationships.

Transactional associations between infant negative emotionality and maternal sensitivity: Maternal emotion dysregulation as a moderator.

The relations between maternal sensitivity and infant negative emotionality have been tested extensively in the previous literature. However, the extent to which these associations reflect unidirectional or bidirectional effects over time remains somewhat uncertain. Further, the possibility that maternal characteristics moderate the extent to which infant negative emotionality predicts maternal sensitivity over time has yet to be tested in cross-lag models. The goal of the present study is to address these gaps. First time mothers (N = 259; 50% White; 50% Black) and their infants participated when infants were 6, 14, and 26 months of age. Infant negative emotionality was assessed via maternal report and direct observation during standardized laboratory tasks, which were subsequently combined to yield a multimethod measure at each wave. Maternal sensitivity was observationally coded at each wave and mothers self-reported emotion dysregulation at 6 and 14 months. A random intercepts cross-lagged model with maternal emotion dysregulation specified as a moderator revealed that infant negative emotionality at 6 months was negatively associated with maternal sensitivity at 14 months, but only among mothers higher in emotion dysregulation. Higher maternal sensitivity was in turn associated with lower infant negative emotionality when infants were 26 months of age. The indirect pathway was significant, lending support for the transactional model. Implications for future research and prevention/intervention are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

500 The Aging Exposome: Characterizing Bidirectional Effects of Exposures and Aging

OBJECTIVES/GOALS: The objective of this study is to synthetically generate and use records of exposure, and so that we can understand the effects of exposure on aging and vice-versa. METHODS/STUDY POPULATION: Quantifying bidirectional effects of environment and aging requires time series of data from all contributing exposures which can span endogenous processes within the body, biological responses of adaptation to environment, and socio-behavioral factors. Gaps in measured data may need to be filled with computationally modeled data. Essentially, the challenge in generating aging exposome is the absence of readily available records for individuals over the course of their life. Instead, these would need to be assimilated from historic person reported data (e.g. residential location, durations, behaviors) along with publically available data. This could lead to potential gaps and uncertainties that would need inform on how the exposomic records can be used for aging research. RESULTS/ANTICIPATED RESULTS: We present a pragmatic approach to generation of longitudinal exposomic and aging records as required for different study archetypes. Such records can then be used to understand the bidirectional effects of exposures and aging. DISCUSSION/SIGNIFICANCE: Effects of a lifetime of environmental and lifestyle exposures on aging or age-associated diseases are not well understood. Characterizing differential, additive and intense sporadic multi-agent exposures require advanced big data and artificial intelligence methods.

The relationship between pre-surgery self-rated health and changes in functional and mental health in older adults: insights from a prospective observational study

BackgroundElective surgeries are among the most common health stressors in later life and put a significant risk at functional and mental health, making them an important target of research into healthy aging and physical resilience. Large-scale longitudinal research mostly conducted in non-clinical samples provided support of the predictive value of self-rated health (SRH) for both functional and mental health. Thus, SRH may have the potential to predict favorable adaptation processes after significant health stressors, that is, physical resilience. So far, a study examining the interplay between SRH, functional and mental health and their relative importance for health changes in the context of health stressors was missing. The present study aimed at addressing this gap.MethodsWe used prospective data of 1,580 inpatients (794 complete cases) aged 70 years or older of the PAWEL study, collected between October 2017 and May 2019 in Germany. Our analyses were based on SRH, functional health (Barthel Index) and self-reported mental health problems (PHQ-4) before and 12 months after major elective surgery. To examine changes and interrelationships in these health indicators, bivariate latent change score (BLCS) models were applied.ResultsOur analyses provided evidence for improvements of SRH, functional and mental health from pre-to-post surgery. BLCS models based on complete cases and the total sample pointed to a complex interplay of SRH, functional health and mental health with bidirectional coupling effects. Better pre-surgery SRH was associated with improvements in functional and mental health, and better pre-surgery functional health and mental health were associated with improvements in SRH from pre-to-post surgery. Effects of pre-surgery SRH on changes in functional health were smaller than those of functional health on changes in SRH.ConclusionsMeaningful changes of SRH, functional and mental health and their interplay could be depicted for the first time in a clinical setting. Our findings provide preliminary support for SRH as a physical resilience factor being associated with improvements in other health indicators after health stressors. Longitudinal studies with more timepoints are needed to fully understand the predictive value of SRH for multidimensional health.Trial registrationPAWEL study, German Clinical Trials Register, number DRKS00013311. Registered 10 November 2017 – Retrospectively registered, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00013311.

The relationship between HMGB1 and autophagy in the pathogenesis of diabetes and its complications.

Diabetes mellitus is a chronic metabolic disorder characterized by elevated blood glucose levels and has become the third leading threat to human health after cancer and cardiovascular disease. Recent studies have shown that autophagy is closely associated with diabetes. Under normal physiological conditions, autophagy promotes cellular homeostasis, reduces damage to healthy tissues and has bidirectional effects on regulating diabetes. However, under pathological conditions, unregulated autophagy activation leads to cell death and may contribute to the progression of diabetes. Therefore, restoring normal autophagy may be a key strategy to treat diabetes. High-mobility group box 1 protein (HMGB1) is a chromatin protein that is mainly present in the nucleus and can be actively secreted or passively released from necrotic, apoptotic, and inflammatory cells. HMGB1 can induce autophagy by activating various pathways. Studies have shown that HMGB1 plays an important role in insulin resistance and diabetes. In this review, we will introduce the biological and structural characteristics of HMGB1 and summarize the existing knowledge on the relationship between HMGB1, autophagy, diabetes, and diabetic complications. We will also summarize potential therapeutic strategies that may be useful for the prevention and treatment of diabetes and its complications.

Causal association of cardiovascular disease with erectile dysfunction: a two-sample bidirectional Mendelian randomization analysis.

The association between cardiovascular diseases (CVD), including ischemic stroke (IS), heart failure (HF), myocardial infarction (MI), and coronary heart disease (CHD), and erectile dysfunction (ED) remains unclear from observational studies. We explored the potential bidirectional association between CVD and ED by Mendelian randomization (MR). Data from genome-wide association studies for CVD in individuals with European ancestry were obtained from several databases, with 1,711,875-977,323 participants, while that for ED included 223,805 participants. We conducted univariate MR (UVMR), inverse variance-weighting (IVW), weighted median, MR-Egger, and multivariate MR (MVMR) analyses to explore the bidirectional causal effects between CVD and ED. UVMR indicated that IS (odds ratios [OR]=1.34, 95% confidence interval [CI]: 1.08-1.21, P=0.007), HF (OR=1.36, 95% CI 1.07-1.74, P=0.013), and CHD (OR=1.15, 95% CI 1.09-1.18, P=0.022) were associated with ED. By MVMR, IS estimates remained significant after accounting for combining single nucleotide polymorphisms from CVDs (OR=1.42, 95%CI: 1.13-1.79, P=0.002). Moreover, the effect of a genetic susceptibility to IS on ED was not mediated by type 2 diabetes or triglycerides; that of HF was not mediated by type 2 diabetes, and that of CHD was not mediated by body mass index. Bidirectional analyses showed that genetic susceptibility to ED did not confer any increased CVD risk. Our results, based on MR, indicated that genetic susceptibility to IS, HF, and CHD was causally associated with ED. These findings can inform prevention and intervention strategies for ED in IS, HF, and CHD patients.

Effects of Post-awakening Light Exposure on Heart Rate Variability in Healthy Male Individuals

Light-induced effects on the autonomic nervous system (ANS) are assumed to be mediated by retinal projections to the hypothalamic suprachiasmatic nucleus (SCN) via different routes. Light information for the circadian system is detected by a subset of intrinsically photosensitive retinal ganglion cells (ipRGCs), however, inconsistency exists in research concerning the effects of light exposure on heart rate variability (HRV). Two within-subject experiments were conducted in a standardized sleep laboratory to investigate effects of light intensity (study I, n = 29: 2 days dim vs. bright light) and spectral composition (study II, n = 24: 3 days using red vs. blue vs. green light) on HRV parameters (RMSSD, LF, HF-HRV, LF/HF ratio). Light exposure was conducted for one-hour in the post-awakening phase at 5:00 AM. Results revealed no significant light intensity effect comparing dim light versus bright white light on HRV parameters. Light color of different wavelengths significantly influenced all HRV parameters except the low frequency, with moderate to large effect sizes. RMSSD values were elevated for all three colors compared to norm values, indicating stronger parasympathetic activation. LED light of different spectral compositions demonstrated bidirectional effects on spectral components of the HRV. Red light decreased the LF/HF ratio within 30 min, whereas with blue light, LF/HF ratio consistently increased across 40 min of light exposure.

Bidirectional effects of oral anticoagulants on gut microbiota in patients with atrial fibrillation.

The imbalance of gut microbiota (GM) is associated with a higher risk of thrombosis in patients with atrial fibrillation (AF). Oral anticoagulants (OACs) have been found to significantly reduce the risk of thromboembolism and increase the risk of bleeding. However, the OAC-induced alterations in gut microbiota in patients with AF remain elusive. In this study, the microbial composition in 42 AF patients who received long-term OAC treatment (AF-OAC group), 47 AF patients who did not (AF group), and 40 volunteers with the risk of AF (control group) were analyzed by 16S rRNA gene sequencing of fecal bacterial DNA. The metagenomic functional prediction of major bacterial taxa was performed using the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) software package. The gut microbiota differed between the AF-OAC and AF groups. The abundance of Bifidobacterium and Lactobacillus decreased in the two disease groups at the genus level, but OACs treatment mitigated the decreasing tendency and increased beneficial bacterial genera, such as Megamonas. In addition, OACs reduced the abundance of pro-inflammatory taxa on the genus Ruminococcus but increased certain potential pathogenic taxa, such as genera Streptococcus, Escherichia-Shigella, and Klebsiella. The Subgroup Linear discriminant analysis effect size (LEfSe) analyses revealed that Bacteroidetes, Brucella, and Ochrobactrum were more abundant in the anticoagulated bleeding AF patients, Akkermansia and Faecalibacterium were more abundant in the non-anticoagulated-bleeding-AF patients. The neutrophil-to-lymphocyte ratio (NLR) was lower in the AF-OAC group compared with the AF group (P < 0.05). Ruminococcus was positively correlated with the NLR and negatively correlated with the CHA2DS2-VASc score (P < 0.05), and the OACs-enriched species (Megamonas and Actinobacteria) was positively correlated with the prothrombin time (PT) (P < 0.05). Ruminococcus and Roseburia were negatively associated with bleeding events (P < 0.05). Our study suggested that OACs might benefit AF patients by reducing the inflammatory response and modulating the composition and abundance of gut microbiota. In particular, OACs increased the abundance of some gut microbiota involved in bleeding and gastrointestinal dysfunction indicating that the exogenous supplementation with Faecalibacterium and Akkermansia might be a prophylactic strategy for AF-OAC patients to lower the risk of bleeding after anticoagulation.

Bidirectional effects of sulfur-oxidizer Acidithiobacillus thiooxidans in uranium bioleaching systems with or without sulfur by mixed acidophilic bacteria

Bidirectional effects of sulfur-oxidizer Acidithiobacillus thiooxidans in uranium bioleaching systems with or without sulfur by mixed acidophilic bacteria