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Philosophical Transactions of the Royal... Jul 2024Decisions to disperse from a habitat stand out among organismal behaviours as pivotal drivers of ecosystem dynamics across scales. Encounters with other species are an...
Decisions to disperse from a habitat stand out among organismal behaviours as pivotal drivers of ecosystem dynamics across scales. Encounters with other species are an important component of adaptive decision-making in dispersal, resulting in widespread behaviours like tracking resources or avoiding consumers in space. Despite this, metacommunity models often treat dispersal as a function of intraspecific density alone. We show, focusing initially on three-species network motifs, that interspecific dispersal rules generally drive a transition in metacommunities from homogeneous steady states to self-organized heterogeneous spatial patterns. However, when ecologically realistic constraints reflecting adaptive behaviours are imposed-prey tracking and predator avoidance-a pronounced homogenizing effect emerges where spatial pattern formation is suppressed. We demonstrate this effect for each motif by computing master stability functions that separate the contributions of local and spatial interactions to pattern formation. We extend this result to species-rich food webs using a random matrix approach, where we find that eventually, webs become large enough to override the homogenizing effect of adaptive dispersal behaviours, leading once again to predominately pattern-forming dynamics. Our results emphasize the critical role of interspecific dispersal rules in shaping spatial patterns across landscapes, highlighting the need to incorporate adaptive behavioural constraints in efforts to link local species interactions and metacommunity structure. This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'.
Topics: Food Chain; Animals; Animal Distribution; Models, Biological; Ecosystem; Population Dynamics; Predatory Behavior
PubMed: 38913053
DOI: 10.1098/rstb.2023.0136 -
Heliyon Jun 2024
PubMed: 38912438
DOI: 10.1016/j.heliyon.2024.e32326 -
GeoHealth Jun 2024Mental health disorders have become a global problem, garnering considerable attention. However, the root causes of deteriorating mental health remain poorly understood,...
Mental health disorders have become a global problem, garnering considerable attention. However, the root causes of deteriorating mental health remain poorly understood, with existing literature predominantly concentrating on socioeconomic conditions and psychological factors. This study uses multi-linear and geographically weighted regressions (GWR) to examine the associations between built and natural environmental attributes and the prevalence of depression in US counties. The findings reveal that job sprawl and land mixed use are highly correlated with a lower risk of depression. Additionally, the presence of green spaces, especially in urban area, is associated with improved mental health. Conversely, higher concentrations of air pollutants, such as PM and CO, along with increased precipitation, are linked to elevated depression rates. When considering spatial correlation through GWR, the impact of population density and social capital on mental health displays substantial spatial heterogeneity. Further analysis, focused on two high depression risk clustering regions (northwestern and southeastern counties), reveals nuanced determinants. In northwestern counties, depression rates are more influenced by factors like precipitation and socioeconomic conditions, including unemployment and income segregation. In southeastern counties, population demographic characteristics, particularly racial composition, are associated with high depression prevalence, followed by built environment factors. Interestingly, job growth and crime rates only emerge as significant factors in the context of high depression risks in southeastern counties. This study underscores the robust linkages and spatial variations between built and natural environments and mental health, emphasizing the need for effective depression treatment to incorporate these multifaceted factors.
PubMed: 38912227
DOI: 10.1029/2024GH001047 -
Frontiers in Physiology 2024The neuropeptides kisspeptin, neurokinin B, and dynorphin A are imperative for the pulsatile secretion of gonadotropin-releasing hormone and luteinizing hormone to...
The neuropeptides kisspeptin, neurokinin B, and dynorphin A are imperative for the pulsatile secretion of gonadotropin-releasing hormone and luteinizing hormone to ultimately regulate reproductive cyclicity. A population of neurons co-expressing these neuropeptides, KNDy neurons, within the arcuate nucleus of the hypothalamus (ARC) are positioned to integrate energy status from afferent neuronal and glial cells. We hypothesized that KNDy-expressing neurons in the ARC of mature ewes are influenced by energy balance. To test this hypothesis, ovary-intact, mature ewes were fed to lose, maintain, or gain body weight and hypothalamic tissue harvested during the luteal phase of the estrous cycle. Fluorescent, multiplex immunohistochemistry with direct antibody conjugation was employed to identify and quantify neurons expressing a single neuropeptide, as well as for the first time report co-expression of kisspeptin, neurokinin B, and dynorphin A protein in the ARC. Previous reports using this population of ewes demonstrated that concentrations of insulin and leptin differed between ewes fed to achieve different body weights and that ewes fed to gain body weight had increased concentrations of progesterone. Moreover, within this population of ewes tanycyte density and cellular penetration into the ARC was increased in ewes fed to gain body weight. Within the current report we have revealed that the number of neurons in the ARC expressing kisspeptin, neurokinin B, and dynorphin A protein was increased in ewes fed to gain body weight. Moreover, the number of KNDy neurons in the ARC expressing all three neuropeptides within a single neuron was decreased in ewes fed to lose body weight and increased in ewes fed to gain body weight when compared to ewes fed to maintain body weight. The cumulative findings of this experimental model suggest that expression of kisspeptin, neurokinin B, and dynorphin A protein in the ARC during the luteal phase of the estrous cycle are influenced by energy balance-induced alterations in circulating concentrations of progesterone that drive changes in morphology and density of tanycytes to ultimately regulate central perception of global energy status. Moreover, these results demonstrate that changes in KNDy neurons within the ARC occur as an adaptation to energy balance, potentially regulated divergently by metabolic milieu via proopiomelanocortin afferents.
PubMed: 38911326
DOI: 10.3389/fphys.2024.1372944 -
Frontiers in Genetics 2024Visna/Maedi virus (VMV) is lentiviral disease of sheep responsible for severe production losses. Multiple genomic regions associated with infection were reported...
Visna/Maedi virus (VMV) is lentiviral disease of sheep responsible for severe production losses. Multiple genomic regions associated with infection were reported indicating genetic complexity. In this study, a combined genome-wide approach using a high-density SNP array has been performed, comparing VMV-infected ( = 78) and non-infected ( = 66) individuals of the Valle del Belice breed. The serological tests showed a seroprevalence of 26%. The comparison among results from different approaches (GWAS, Fisher's exact test and the F analysis) revealed two association signals: on OAR03 close to the gene and on OAR05 close to the gene. To the best of our knowledge, there has been no previous association between these genes and lentiviral infection in any species. The gene plays a role in pain response, synaptic transmission, and receptor clustering, while is involved in the development of immune-related disorders. The results highlighted new aspects of the genetic complexity related to the resistance/susceptibility to VMV in sheep, confirming that studies on different breeds can lead to different results. The ideal approach for validation of the markers identified in our study is to use samples from a population independent from the discovery population with the same phenotype used in the discovery stage.
PubMed: 38911298
DOI: 10.3389/fgene.2024.1376883 -
Evolutionary Applications Jun 2024Recent work has revealed the importance of contemporary evolution in shaping ecological outcomes. In particular, rapid evolutionary divergence between populations has...
Recent work has revealed the importance of contemporary evolution in shaping ecological outcomes. In particular, rapid evolutionary divergence between populations has been shown to impact the ecology of populations, communities, and ecosystems. While studies have focused largely on the role of adaptive divergence in generating ecologically important variation among populations, much less is known about the role of gene flow in shaping ecological outcomes. After divergence, populations may continue to interact through gene flow, which may influence evolutionary and ecological processes. Here, we investigate the role of gene flow in shaping the contemporary evolution and ecology of recently diverged populations of anadromous steelhead and resident rainbow trout (). Results show that resident rainbow trout introduced above waterfalls have diverged evolutionarily from downstream anadromous steelhead, which were the source of introductions. However, the movement of fish from above to below the waterfalls has facilitated gene flow, which has reshaped genetic and phenotypic variation in the anadromous source population. In particular, gene flow has led to an increased frequency of residency, which in turn has altered population density, size structure, and sex ratio. This result establishes gene flow as a contemporary evolutionary process that can have important ecological outcomes. From a management perspective, anadromous steelhead are generally regarded as a higher conservation priority than resident rainbow trout, even when found within the same watershed. Our results show that anadromous and resident populations may be connected via gene flow, with important ecological consequences. Such eco-evolutionary processes should be considered when managing recently diverged populations connected by gene flow.
PubMed: 38911264
DOI: 10.1111/eva.13712 -
Human Reproduction Open 2024Are cardiovascular disease (CVD) risk factors causally associated with higher risk of infertility among women and men?
STUDY QUESTION
Are cardiovascular disease (CVD) risk factors causally associated with higher risk of infertility among women and men?
SUMMARY ANSWER
We found evidence to support a causal relationship between smoking initiation and history of infertility in women.
WHAT IS KNOWN ALREADY
Several CVD risk factors are associated with history of infertility. Previous studies using Mendelian randomization (MR) further support a causal relationship between BMI and infertility in women.
STUDY DESIGN SIZE DURATION
We used data from the Trøndelag Health Study (HUNT) in Norway, a prospective population-based cohort study, including 26 811 women and 15 598 men participating in three survey collections in 1995-1997 (HUNT2), 2006-2008 (HUNT3), and 2017-2019 (HUNT4).
PARTICIPANTS/MATERIALS SETTING METHODS
Our outcome was women's self-reported history of infertility, defined as ever having tried to conceive for 12 months or more or having used ART. We assigned the history of infertility reported by women to their male partners; therefore, the measure of infertility was on the couple level. We used both conventional multivariable analyses and one-sample MR analyses to evaluate the association between female and male CVD risk factors (including BMI, blood pressure, lipid profile measurements, and smoking behaviours) and history of infertility in women and men, separately.
MAIN RESULTS AND THE ROLE OF CHANCE
A total of 4702 women (18%) and 2508 men (16%) were classified with a history of infertility. We found a higher risk of infertility among female smokers compared to non-smokers in both multivariable and MR analyses (odds ratio (OR) in multivariable analysis, 1.20; 95% CI, 1.12-1.28; OR in MR analysis, 1.13; CI, 1.02-1.26), and potentially for higher BMI (OR in multivariable analysis, 1.13; CI, 1.09-1.18; OR in MR analysis, 1.11, CI, 0.92-1.34). In multivariable analysis in women, we also found evidence of associations between triglyceride levels, high-density lipoprotein cholesterol, lifetime smoking index, and smoking intensity with higher risk of infertility. However, these results were not consistent in MR analyses. We found no robust or consistent associations between male CVD risk factors and infertility.
LIMITATIONS REASONS FOR CAUTION
Our main limitation was that the CVD risk factors measured might not adequately capture the relevant time periods for when couples were trying to conceive. Additionally, we did not have information on causes of infertility in either women or men.
WIDER IMPLICATIONS OF THE FINDINGS
Women with infertility could have a worse CVD risk factor profile and thus public health interventions aimed at reducing the impact of some CVD risk factors, such as smoking and BMI, could reduce the burden of infertility. However, additional MR studies of the relationship between CVD risk factors and infertility with a larger sample size would be of value.
STUDY FUNDING/COMPETING INTERESTS
The study was supported by a grant from the European Research Council under the European Union's Horizon 2020 research and innovation program (grant agreements no. 947684). This research was also supported by the Research Council of Norway through its Centres of Excellence funding scheme (project no. 262700) and partly funded by the Research Council of Norway, project: Women's fertility-an essential component of health and well-being (project no. 320656). D.A.L. and A.F. work in a unit that is supported by the University of Bristol and the UK Medical Research Council (MC_UU_00011/6). D.A.L.'s contribution to the article is supported by the European Research Council (101021566), the British Heart Foundation (CH/F/20/90003 and AA/18/7/34219). S.B.'s contribution to the article is supported by the Wellcome Trust (225790/Z/22/Z). B.M.B. is funded by The Liaison Committee for education, research and innovation in Central Norway; and the Joint Research Committee between St. Olavs Hospital and the Faculty of Medicine and Health Sciences, NTNU. The genotyping in HUNT was financed by the National Institute of Health (NIH); University of Michigan; The Research Council of Norway; The Liaison Committee for education, research and innovation in Central Norway; and the Joint Research Committee between St. Olavs Hospital and the Faculty of Medicine and Health Sciences, NTNU. None of the funding organizations influenced the study design, reporting, or interpretation of results. The views expressed in the present article are those of the authors and not necessarily any acknowledged funding organization. D.A.L. reports grants from Medtronic Ltd and Roche Diagnostics outside the submitted work. The other authors have no conflicts of interest.
TRIAL REGISTRATION NUMBER
N/A.
PubMed: 38911051
DOI: 10.1093/hropen/hoae033 -
Frontiers in Endocrinology 2024In China, osteoporosis has become a major health concern among elderly population, imposing significant burden on the country's social and economic systems. The monocyte... (Review)
Review
OBJECTIVES
In China, osteoporosis has become a major health concern among elderly population, imposing significant burden on the country's social and economic systems. The monocyte to high-density lipoprotein ratio (MHR) has been currently recommended as a novel marker of inflammation and oxidative stress associated with osteoporosis in type 2 diabetes mellitus (T2DM). However, its reliability in non-diabetic elderly populations remains unclear. The present study was to evaluate the association between MHR and osteoporosis in a non-diabetic elderly population.
METHODS
The clinical data of 240 non-diabetic elderly subjects (115 in the osteoporosis group and 125 in the normal bone group) were retrospectively analyzed and all statistical analyses were performed by using SPSS 26.0.
RESULTS
Differences in age, neutrophils, lymphocytes, monocytes, MHR, uric acid, creatinine, triglycerides,and high-density lipoprotein cholesterol were found to be statistically significant between the two groups. A binary logistic regression model was conducted by including age, MHR, UA and Cr as variables. The results showed that age was an independent risk factor and MHR was an independent protective factor for bone abnormality in the non-diabetic elderly population. The ROC analysis showed that the area under the curve for the predictive effect of MHR, age and their combined test on osteoporosis in non-diabetic elderly populations was 0.623, 0.728 and 0.761, respectively; the correlation analysis showed that MHR was positively correlated with lumbar and hip BMD, and negatively associated with femoral neck stress ratio, femoral intertrochanteric stress ratio, and femoral stem stress ratio, showing statistically significant differences (P<0.05).
CONCLUSIONS
For the non-diabetic elderly population: the MHR is a protective factor against bone abnormalities and was significantly higher in the normal bone group than in the abnormal bone group.
Topics: Humans; Aged; Male; Female; Osteoporosis; Retrospective Studies; Monocytes; Lipoproteins, HDL; China; Protective Factors; Middle Aged; Biomarkers; Risk Factors; Aged, 80 and over; Bone Density
PubMed: 38911035
DOI: 10.3389/fendo.2024.1408467 -
Cureus May 2024Introduction Type 2 diabetes mellitus (T2DM), a prevalent chronic metabolic disorder, necessitates multifaceted treatment approaches. Emerging studies highlight the...
Retrospective Observational Study on Assessing Sitagliptin and Dapagliflozin as a Fixed-Dose Combination in the Indian Population With Type 2 Diabetes Mellitus: The SIDAXA Study.
Introduction Type 2 diabetes mellitus (T2DM), a prevalent chronic metabolic disorder, necessitates multifaceted treatment approaches. Emerging studies highlight the cardiovascular advantages of sodium-glucose transport protein 2 (SGLT2) and dipeptidyl peptidase 4 (DPP-4) inhibitors in T2DM. This investigation delves into the synergistic effects of the fixed-dose combination (FDC) of sitagliptin and dapagliflozin, offering insights into its safety and efficacy for the Indian population. Methods This real-world, retrospective, observational study spanned 328 cases across 111 Indian centres, evaluating the safety, efficacy, and clinical utilization of the sitagliptin and dapagliflozin FDC in T2DM patients after obtaining ethical approval. Assessments at baseline, week four, and week 12 encompassed hemoglobin A1C (HbA1C), fasting plasma glucose (FPG), postprandial blood glucose (PPBG), low-density lipoprotein cholesterol (LDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP), and weight change. The statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 29.0.1.0(171) (IBM Corp., Armonk, NY, USA) with a significance level p<0.05. Results Study participants [mean age: 51.14±5.55 years, 77.74% (n=255) males, 22.26% (n=73) females] exhibited prevalent risk factors like sedentary lifestyle (n=167, 50.91%) and smoking (n=147, 44.82%). Comorbidities included hypertension (n=235, 71.65%) and dyslipidaemia (n=139, 42.38%). Metformin (n=282, 85.98%) and sulfonylurea (n=134, 40.85%) were commonly prescribed concomitant oral antidiabetic agents (OADs). FDC administration significantly reduced HbA1c by 1.05 ± 0.83% (p < 0.0001) at week 12. FPG and PPBG showed significant reductions of 22.98 ± 22.23 mg/dL (p < 0.0001), 165.50 ± 37.02 mg/dL and 40.94 ± 36.04 mg/dL (p < 0.0001) at four weeks respectively. By week 12, significant reductions were noted in SBP (14.61±13.98mmHg reduction, p-value <0.0001), DBP (7.80±8.45mmHg reduction, p-value <0.0001), and LDL-C levels (18.14±23.95 mg/dL reduction, p-value <0.0001). In patients with established cardiovascular disease, there was reduction in HbA1c levels by 1.02 ± 0.63% after 12 weeks, with FPG decreasing by 54.52 ± 32.67 mg/dL and PPBG decreasing by 88.73 ± 44.90 mg/dL. Treatment-emergent adverse events included headache, changes in micturition, genital mycotic infection, and nausea and diarrhoea which were mild, transient, and necessitated no treatment discontinuation. Conclusion The FDC of sitagliptin and dapagliflozin significantly improved glycaemic control and lipid profiles in T2DM patients, particularly those with coronary artery disease. It demonstrated a favourable safety profile in the Indian population, signifying its potential as an effective and well-tolerated therapeutic option in patients with established cardiovascular disease.
PubMed: 38910691
DOI: 10.7759/cureus.60815 -
Journal of the Formosan Medical... Jun 2024Fluid resuscitation reduces mortality and morbidity in acute pancreatitis (AP); however, whether glucose-containing fluids negatively impact AP remains uncertain. We...
INTRODUCTION
Fluid resuscitation reduces mortality and morbidity in acute pancreatitis (AP); however, whether glucose-containing fluids negatively impact AP remains uncertain. We aimed to examine the association between glucose-containing fluids and AP outcomes.
METHODS
This multicenter retrospective cohort study included patients diagnosed with AP between January 2015 and December 2018. Glucose density was defined as total glucose content divided by total fluid volume (g/dl) on day 1, and was considered high if the level exceeded the median. Endpoints were early organ failure (OF), including cardiovascular, renal, or respiratory system failure within 7 days; 30-day OF; ICU admission; and AP-related 90-day mortality. Logistic regression models, restricted cubic spline curves, and Cox proportional hazards models were used for statistical analysis.
RESULTS
From the database, 1,146 patients with AP were included. Early OF occurred in 8.8% of patients within 7 days. The high glucose-density group (>5 g/dl) had increased risk of early OF (9.7% vs. 8.2%; adjusted odds ratio [aOR], 1.69; 95% confidence interval [CI], 1.03-2.80; P = 0.039), respiratory failure (8.0% vs. 6.2%; aOR, 1.88; 95% CI, 1.09-3.24; P = 0.024), cardiovascular failure (3.4% vs. 2.4%; aOR, 3.59; 95% CI, 1.28-10.0; P = 0.015), and ICU admission (6.8% vs. 5.8%; aOR, 2.06; 95% CI, 1.08-3.94; P = 0.029), with a dose-response effect observed for cardiovascular failure and ICU admission. A significant increase 30-day OF risk (adjusted hazard ratio [aHR], 1.70; 95% CI, 1.19-2.45) was also noted.
CONCLUSION
Excess glucose-containing fluid was associated with increased risks of overall, respiratory, and cardiovascular OF and ICU admission in AP.
PubMed: 38910095
DOI: 10.1016/j.jfma.2024.05.022