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1.
Artigo em Inglês | MEDLINE | ID: mdl-39117904

RESUMO

The basolateral amygdala (BLA) is reliably activated by psychological stress and hyperactive in conditions of pathological stress or trauma; however, subsets of BLA neurons are also readily activated by rewarding stimuli and can suppress fear and avoidance behaviours. The BLA is highly heterogeneous anatomically, exhibiting continuous molecular and connectivity gradients throughout the entire structure. A critical gap remains in understanding the anatomical specificity of amygdala subregions, circuits, and cell types explicitly activated by acute stress and how they are dynamically activated throughout stimulus exposure. Using a combination of topographical mapping for the activity-responsive protein FOS and fiber photometry to measure calcium transients in real-time, we sought to characterize the spatial and temporal patterns of BLA activation in response to a range of novel stressors (shock, swim, restraint, predator odour) and non-aversive, but novel stimuli (crackers, citral odour). We report four main findings: (1) the BLA exhibits clear spatial activation gradients in response to novel stimuli throughout the medial-lateral and dorsal-ventral axes, with aversive stimuli strongly biasing activation towards medial aspects of the BLA; (2) novel stimuli elicit distinct temporal activation patterns, with stressful stimuli exhibiting particularly enhanced or prolonged temporal activation patterns; (3) changes in BLA activity are associated with changes in behavioural state; and (4) norepinephrine enhances stress-induced activation of BLA neurons via the ß-noradrenergic receptor. Moving forward, it will be imperative to combine our understanding of activation gradients with molecular and circuit-specificity.

2.
Langmuir ; 40(33): 17387-17395, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39115153

RESUMO

Despite the known impacts on climate change of carbon dioxide emissions, the continued use of fossil fuels for energy generation leading to the emission of carbon dioxide (CO2) into the atmosphere is evident. Therefore, innovation to address and reduce CO2 emissions from industrial operations remains an urgent and crucial priority. A viable strategy in the area is postcombustion capture mainly through absorption by aqueous alkanolamines, which focuses on the separation of CO2 from flue gas, despite its limitations. Within this context, porous materials, particularly metal-organic frameworks (MOFs), have arisen as favorable alternatives owing to their significant adsorption capacity, selectivity, and reduced regeneration energy demands. This research evaluates the engineering insights into tailored MOFs for enhanced CO2 capture, focusing on three series of MOFs (ZIF, UiO-66, and BTC) to investigate the effects of organic ligands, functional groups, and metal ions. The evaluation encompassed a range of aspects including adsorption isotherms of pure gases [CO2 and nitrogen (N2)] and mixed gas mixture (CO2 and N2 with 15:85% ratio), along with utilization of the ideal adsorbed solution theory (IAST) to simulate multicomponent gas adsorption isotherms. Moreover, the reliability of IAST for mixed gas adsorption prediction has been investigated in detail. The research offers valuable insights into the correlation between the characteristics of MOFs and their effectiveness in gas separation and how these characteristics contribute to the differences between IAST predictions and experimental results. The findings enhance the understanding of how to enhance MOF characteristics in order to reduce CO2 emissions and also highlight the need for advanced models that consider thermodynamic nonidealities to accurately predict the behavior of mixed gas adsorption in MOFs. As a result, the incorporation of MOFs with enhanced predictability and reliability into CO2 capture industrial processes is facilitated.

3.
J Pain ; : 104649, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39121915

RESUMO

Humans use cannabinoid drugs to alleviate pain. As cannabis and cannabinoids are legalized in the United States for medicinal and recreational use, it has become critical to determine the potential utilities and harms of cannabinoid drugs in individuals living with chronic pain. Here, we tested the effects of repeated ∆9-tetrahydrocannabinol (THC) vapor inhalation on thermal nociception and mechanical sensitivity, in adult male and female Wistar rats using a chronic inflammatory pain model (ie, treated with complete Freund's adjuvant [CFA]). We report that repeated THC vapor inhalation rescues thermal hyperalgesia in males and females treated with CFA and also reduces mechanical hypersensitivity in CFA males but not females. Many of the antihyperalgesic effects of chronic THC vapor were still observable 24 hours after cessation of the last THC exposure. We also report plasma levels of THC and its major metabolites, some of which are cannabinoid type-1 receptor agonists, after the first and tenth days of THC vapor inhalation. Finally, we report that systemic administration of the cannabinoid type-1 receptor inverse agonist AM251 (1 mg/kg, I.P.) blocks the antihyperalgesic effects of THC vapor in males and females. These data provide a foundation for future work that will explore the cells and circuits underlying the antihyperalgesic effects of THC vapor inhalation in individuals with chronic inflammatory pain. PERSPECTIVE: Cannabinoids are thought to have potential utility in the treatment of chronic pain, but few animal studies have tested the effects of chronic THC or cannabis in animal models of chronic pain. We tested the effects of repeated THC vapor inhalation on chronic pain-related outcomes in male and female animals.

4.
J Neurosci Res ; 102(7): e25369, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39037062

RESUMO

Cannabis consumption has increased from 1.5% to 2.5% in Canada between 2012 and 2019. Clinical studies have indicated effects of prenatal cannabis exposure on birth weight, substance use, and neurodevelopmental disorders, but are confounded by several difficult to control variables. Animal models allow for examination of the mechanism of cannabis-induced changes in neurodevelopment and behavior, while controlling dose and timing. Several animal models of prenatal cannabis exposure exist which provide varying levels of construct validity, control of dose, and exposure to maternal stress. Using a voluntary oral consumption model, mouse dams received 5 mg/kg Δ9-tetrahydrocannabinol (THC) whole cannabis oil in peanut butter daily from gestational day 1 (GD1) to postnatal day 10 (PD10). At GD1, GD18, PD1, PD10, and PD15, maternal plasma was collected; pup brains were collected from GD18 onward. Pup brains had higher levels of THC and cannabidiol at each time point, each of which persisted in maternal plasma and pup brains past the end of treatment (PD15). Male and female adolescent offspring were examined for changes to ventral tegmental area (VTA) dopamine neuron activity and cocaine-seeking behavior. Prenatal and early postnatal (GD1-PD10) cannabis-exposed male, but not female mice had decreased gamma-aminobutyric acid (GABAergic) input, depolarized resting membrane potential, and increased spontaneous firing of VTA dopamine neurons. Cannabis-exposed offspring showed faster decay of N-methyl-D-aspartate (NMDA) currents in both sexes. However, no differences in cocaine-seeking behavior were noted. These data characterize a voluntary prenatal cannabis exposure model and demonstrates VTA dopamine neuronal activity is disinhibited in offspring.


Assuntos
Cocaína , Neurônios Dopaminérgicos , Efeitos Tardios da Exposição Pré-Natal , Área Tegmentar Ventral , Animais , Feminino , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo , Gravidez , Camundongos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Masculino , Cocaína/farmacologia , Cocaína/toxicidade , Dronabinol/toxicidade , Dronabinol/farmacologia , Camundongos Endogâmicos C57BL , Cannabis
5.
J Econ Entomol ; 117(4): 1459-1467, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38936416

RESUMO

Mediterranean fruit fly (Medfly) Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is a globally significant economic pest for which lure based trapping can be used to monitor established populations and for surveillance. Either female- or male-targeted traps can be used; however, recommendations on which to apply are inconsistent and many programs rely on male-targeted traps. Here, we compare the performance of male-targeted traps (Lynfield Trap with Trimedlure) and female-targeted traps (Biotrap Globe trap with the 3-component lure-TMA Plus) in apple orchards in south-west Western Australia over 2 years (September 2019 to September 2021). Male-targeted traps caught more Medflies overall than female-targeted traps, although the difference was minor. However, female-targeted traps were better at attracting Medfly early in the season when populations were small; and were more likely to capture at least one fly when their paired male-targeted trap caught none. Conversely, male-targeted traps were more likely to capture Medflies late in the season and were more likely to catch high numbers of Medflies. Consequently, female-targeted traps may be better at detecting Medfly early in the season, and male-targeted traps may be better at detecting Medfly abundance late in the season, at least in apple orchards. Our results suggest that either or both trap-types could be used for monitoring Medfly populations, with the optimal solution being dependent on the intended application.


Assuntos
Ceratitis capitata , Controle de Insetos , Malus , Animais , Feminino , Masculino , Controle de Insetos/métodos , Feromônios/farmacologia , Austrália Ocidental
6.
Chemistry ; 30(44): e202400717, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38825571

RESUMO

Hydrogen may play a critical role in our efforts to de-carbonize by 2050. However, there remain technical challenges in the storage and transport of hydrogen. Metal-organic frameworks (MOFs) have shown significant promise for hydrogen storage at cryogenic temperatures. A material that can meet the US department of energy (DOE) ultimate goal of 6.5 wt. % for gravimetric performance and 50 g/L for volumetric storage at near-ambient temperatures would unlock hydrogen as a future fuel source for on-board applications. Metal-organic frameworks typically have low heat of adsorptions (i. e. 4-7 kJ/mol), whereas for storing significant quantities of hydrogen at near-ambient temperatures, 15-25 kJ/mol is likely required. In this review we explore the current methods used (i. e., open-metal sites, alkali dopants and hydrogen spillover) for promoting strong adsorption within MOFs. Further we discuss MOF-based materials with respect to the technical aspects of deliverable capacity, kinetics and stability.

7.
J Am Chem Soc ; 146(20): 14058-14066, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38733559

RESUMO

Metal-organic framework (MOF) membranes with high ion selectivity are highly desirable for direct lithium-ion (Li+) separation from industrial brines. However, very few MOF membranes can efficiently separate Li+ from brines of high Mg2+/Li+ concentration ratios and keep stable in ultrahigh Mg2+-concentrated brines. This work reports a type of MOF-channel membranes (MOFCMs) by growing UiO-66-(SH)2 into the nanochannels of polymer substrates to improve the efficiency of MOF membranes for challenging Li+ extraction. The resulting membranes demonstrate excellent monovalent metal ion selectivity over divalent metal ions, with Li+/Mg2+ selectivity up to 103 since Mg2+ should overcome a higher energy barrier than Li+ when transported through the MOF pores, as confirmed by molecular dynamics simulations. Under dual-ion diffusion, as the Mg2+/Li+ mole ratio of the feed solution increases from 0.2 to 30, the membrane Li+/Mg2+ selectivity decreases from 1516 to 19, corresponding to the purity of lithium products between 99.9 and 95.0%. Further research on multi-ion diffusion that involves Mg2+ and three monovalent metal ions (K+, Na+, and Li+, referred to as M+) in the feed solutions shows a significant improvement in Li+/Mg2+ separation efficiency. The Li+/Mg2+ selectivity can go up to 1114 when the Mg2+/M+ molar concentration ratio is 1:1, and it remains at 19 when the ratio is 30:1. The membrane selectivity is also stable for 30 days in a highly concentrated solution with a high Mg2+/Li+ concentration ratio. These results indicate the feasibility of the MOFCMs for direct lithium extraction from brines with Mg2+ concentrations up to 3.5 M. This study provides an alternative strategy for designing efficient MOF membranes in extracting valuable minerals in the future.

8.
Adv Mater ; 36(29): e2400709, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38721928

RESUMO

Membrane-based enantioselective separation is a promising method for chiral resolution due to its low cost and high efficiency. However, scalable fabrication of chiral separation membranes displaying both high enantioselectivity and high flux of enantiomers is still a challenge. Here, the authors report the preparation of homochiral porous organic cage (Covalent cage 3 (CC3)-R)-based enantioselective thin-film-composite membranes using polyamide (PA) as the matrix, where fully organic and solvent-processable cage crystals have good compatibility with the polymer scaffold. The hierarchical CC3-R channels consist of chiral selective windows and inner cavities, leading to favorable chiral resolution and permeation of enantiomers; the CC3-R/PA composite membranes display an enantiomeric excess of 95.2% for R-(+)-limonene over S-(-)-limonene and a high flux of 99.9 mg h-1 m-2. This work sheds light on the use of homochiral porous organic cages for preparing enantioselective membranes and demonstrates a new route for the development of next-generation chiral separation membranes.

9.
Nat Med ; 30(6): 1749-1760, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38806679

RESUMO

Fibrotic diseases affect multiple organs and are associated with morbidity and mortality. To examine organ-specific and shared biologic mechanisms that underlie fibrosis in different organs, we developed machine learning models to quantify T1 time, a marker of interstitial fibrosis, in the liver, pancreas, heart and kidney among 43,881 UK Biobank participants who underwent magnetic resonance imaging. In phenome-wide association analyses, we demonstrate the association of increased organ-specific T1 time, reflecting increased interstitial fibrosis, with prevalent diseases across multiple organ systems. In genome-wide association analyses, we identified 27, 18, 11 and 10 independent genetic loci associated with liver, pancreas, myocardial and renal cortex T1 time, respectively. There was a modest genetic correlation between the examined organs. Several loci overlapped across the examined organs implicating genes involved in a myriad of biologic pathways including metal ion transport (SLC39A8, HFE and TMPRSS6), glucose metabolism (PCK2), blood group antigens (ABO and FUT2), immune function (BANK1 and PPP3CA), inflammation (NFKB1) and mitosis (CENPE). Finally, we found that an increasing number of organs with T1 time falling in the top quintile was associated with increased mortality in the population. Individuals with a high burden of fibrosis in ≥3 organs had a 3-fold increase in mortality compared to those with a low burden of fibrosis across all examined organs in multivariable-adjusted analysis (hazard ratio = 3.31, 95% confidence interval 1.77-6.19; P = 1.78 × 10-4). By leveraging machine learning to quantify T1 time across multiple organs at scale, we uncovered new organ-specific and shared biologic pathways underlying fibrosis that may provide therapeutic targets.


Assuntos
Fibrose , Estudo de Associação Genômica Ampla , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Aprendizado de Máquina , Idoso , Pâncreas/patologia , Pâncreas/diagnóstico por imagem , Especificidade de Órgãos/genética , Rim/patologia , Fígado/patologia , Fígado/metabolismo , Miocárdio/patologia , Miocárdio/metabolismo , Adulto
10.
Int J Obes (Lond) ; 48(7): 981-992, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38528095

RESUMO

BACKGROUND: 4-20% of people report using cannabis during pregnancy, thereby it is essential to assess the associated risks. There is some evidence that prenatal cannabis exposure (PCE) may be associated with increased risk for developing of obesity and diabetes later in life, however this has not been well explored under controlled conditions. The aim of this study was to use a translational THC vapor model in rodents to characterize the effects of PCE on adiposity, glucose metabolism, and feeding patterns in adulthood, with focus on potential sex differences. METHODS: Pregnant Sprague Dawley rats were exposed to vaporized THC (100 mg/ml) or control (polyethylene glycol vehicle) across the entire gestational period. Adult offspring from PCE (n = 24) or control (n = 24) litters were subjected to measures of adiposity, glucose metabolism and feeding behavior. Rats were then placed onto special diets (60% high-fat diet [HFD] or control 10% low fat diet [LFD]) for 4-months, then re-subjected to adiposity, glucose metabolism and feeding behavior measurements. RESULTS: PCE did not influence maternal weight or food consumption but was associated with transient decreased pup weight. PCE did not initially influence bodyweight or adiposity, but PCE did significantly reduce the rate of bodyweight gain when on HFD/LFD, regardless of which diet. Further, PCE had complex effects on glucose metabolism and feeding behavior that were both sex and diet dependent. No effects of PCE were found on plasma leptin or insulin, or white adipose tissue mass. CONCLUSIONS: PCE may not promote obesity development but may increase risk for diabetes and abnormal eating habits under certain biological and environmental conditions. Overall, this data enhances current understanding of the potential impacts of PCE.


Assuntos
Peso Corporal , Dieta Hiperlipídica , Dronabinol , Comportamento Alimentar , Efeitos Tardios da Exposição Pré-Natal , Ratos Sprague-Dawley , Animais , Gravidez , Feminino , Ratos , Dieta Hiperlipídica/efeitos adversos , Masculino , Comportamento Alimentar/efeitos dos fármacos , Dronabinol/farmacologia , Peso Corporal/efeitos dos fármacos , Obesidade/metabolismo , Glicemia/metabolismo , Modelos Animais de Doenças , Glucose/metabolismo , Adiposidade/efeitos dos fármacos
11.
Artigo em Inglês | MEDLINE | ID: mdl-38541301

RESUMO

Extensive research has highlighted the strong association between chronic stress and negative health outcomes. This relationship is influenced by various factors, including sociobehavioral, environmental, and genetic and epigenomic forces. To comprehensively assess an individual's stress levels, we propose the development of the Chronic Stress Indicator (CSI), a novel comprehensive multifaceted tool that incorporates key biological, anthropometric, behavioral, and socioeconomic factors. The objective of this study is to assess the effectiveness of the CSI compared to Allostatic Load (AL), a type of chronic stress, in identifying health issues related to stress. The objective of this research is to evaluate the performance of the Chronic Stress Indicator (CSI) versus Allostatic Load (AL) in detecting adverse health outcomes within the U.S. demographic aged 20-49. The information used for this study was sourced from the National Health and Nutrition Examination Survey (NHANES), carried out from 2001 to 2004. Logistic regression modeling was employed to calculate odds ratios and confidence intervals. The Wilcoxon rank-sum test was employed to assess differences in means, whereas the chi-square test, accompanied by Cramer's V statistic, was used to examine the association among categorical variables. Additionally, the relationship between continuous variables was analyzed using Pearson's correlation coefficient. Our association tests show that the length of occupation activity and health status were among the strongest associations to CSI risk. Based on our logistic regression models, age and sex were found to be significant factors in determining AL. We also found that age, smoking, and longest occupation activity were significant factors of CSI risk. These findings suggest a need for individuals to limit smoking as it may lead to higher overall stress despite its common use as a coping mechanism for stress. We should also review the level of occupational activity a job has before continuously working on it as this may also lead to higher cumulative stress.


Assuntos
Fumar , Estresse Psicológico , Humanos , Inquéritos Nutricionais , Fatores Socioeconômicos , Fumar/epidemiologia
12.
J Vasc Surg Cases Innov Tech ; 10(2): 101398, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38304297

RESUMO

Splenic artery pseudoaneurysm is a rare and potentially fatal condition. In the present report, we describe the case of a 50-year-old woman with chronic pancreatitis who presented with worsening abdominal pain. Computed tomography demonstrated a 3.5-cm splenic artery pseudoaneurysm of the mid-splenic artery. The patient underwent attempted endovascular repair of the pseudoaneurysm that was unsuccessful. Open conversion revealed an inaccessible splenic artery due to chronic pancreatitis that resulted in dense retroperitoneal fibrosis, and repair was achieved via direct thrombin injection under ultrasound guidance of the pseudoaneurysm and splenectomy. The patient recovered well, and computed tomography at 3 days postoperatively revealed complete thrombosis of the pseudoaneurysm.

13.
ChemSusChem ; 17(11): e202301602, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38298090

RESUMO

Hypercrosslinked polymers (HCPs) are widely used in ion exchange, water purification, and gas separation. However, HCP synthesis typically requires hazardous halogenated solvents e. g., dichloroethane, dichloromethane and chloroform which are toxic to human health and environment. Herein we hypothesize that the use of halogenated solvents in HCP synthesis can be overcome with deep eutectic solvents (DES) comprising metal halides-FeCl3, ZnCl2 that can act as both the solvent hydrogen bond donor and catalyst for polymer crosslinking via Friedel Crafts alkylation. We validated our hypothesis by synthesizing HCPs in DESs via internal and external crosslinking strategies. [ChCl][ZnCl2]2 and [ChCl][FeCl3]2 was more suitable for internal and external hypercrosslinking, respectively. The specific surface areas of HCPs synthesized in DES were 20-60 % lower than those from halogenated solvents, but their CO2/N2 selectivities were up to 453 % higher (CO2/N2 selectivity of poly-α,α'-dichloro-p-xylene synthesized in [ChCl][ZnCl2]2 via internal crosslinking reached a value of 105). This was attributed to the narrower pore size distributions of HCPs synthesized in DESs.

14.
Nucleic Acids Res ; 52(5): e25, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38281134

RESUMO

Protein-specific Chromatin Conformation Capture (3C)-based technologies have become essential for identifying distal genomic interactions with critical roles in gene regulation. The standard techniques include Chromatin Interaction Analysis by Paired-End Tag (ChIA-PET), in situ Hi-C followed by chromatin immunoprecipitation (HiChIP) also known as PLAC-seq. To identify chromatin interactions from these data, a variety of computational methods have emerged. Although these state-of-art methods address many issues with loop calling, only few methods can fit different data types simultaneously, and the accuracy as well as the efficiency these approaches remains limited. Here we have generated a pipeline, MMCT-Loop, which ensures the accurate identification of strong loops as well as dynamic or weak loops through a mixed model. MMCT-Loop outperforms existing methods in accuracy, and the detected loops show higher activation functionality. To highlight the utility of MMCT-Loop, we applied it to conformational data derived from neural stem cell (NSCs) and uncovered several previously unidentified regulatory regions for key master regulators of stem cell identity. MMCT-Loop is an accurate and efficient loop caller for targeted conformation capture data, which supports raw data or pre-processed valid pairs as input, the output interactions are formatted and easily uploaded to a genome browser for visualization.


Assuntos
Cromatina , Técnicas Genéticas , Genômica , Cromatina/química , Cromatina/genética , Imunoprecipitação da Cromatina/métodos , Cromossomos , Genoma , Genômica/métodos
15.
Ecology ; 105(2): e4219, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38037301

RESUMO

A tenet of ecology is that temporal variability in ecological structure and processes tends to decrease with increasing spatial scales (from locales to regions) and levels of biological organization (from populations to communities). However, patterns in temporal variability across trophic levels and the mechanisms that produce them remain poorly understood. Here we analyzed the abundance time series of spatially structured communities (i.e., metacommunities) spanning basal resources to top predators from 355 freshwater sites across three continents. Specifically, we used a hierarchical partitioning method to disentangle the propagation of temporal variability in abundance across spatial scales and trophic levels. We then used structural equation modeling to determine if the strength and direction of relationships between temporal variability, synchrony, biodiversity, and environmental and spatial settings depended on trophic level and spatial scale. We found that temporal variability in abundance decreased from producers to tertiary consumers but did so mainly at the local scale. Species population synchrony within sites increased with trophic level, whereas synchrony among communities decreased. At the local scale, temporal variability in precipitation and species diversity were associated with population variability (linear partial coefficient, ß = 0.23) and population synchrony (ß = -0.39) similarly across trophic levels, respectively. At the regional scale, community synchrony was not related to climatic or spatial predictors, but the strength of relationships between metacommunity variability and community synchrony decreased systematically from top predators (ß = 0.73) to secondary consumers (ß = 0.54), to primary consumers (ß = 0.30) to producers (ß = 0). Our results suggest that mobile predators may often stabilize metacommunities by buffering variability that originates at the base of food webs. This finding illustrates that the trophic structure of metacommunities, which integrates variation in organismal body size and its correlates, should be considered when investigating ecological stability in natural systems. More broadly, our work advances the notion that temporal stability is an emergent property of ecosystems that may be threatened in complex ways by biodiversity loss and habitat fragmentation.


Assuntos
Ecossistema , Cadeia Alimentar , Biodiversidade , Água Doce , Fatores de Tempo
16.
Neuroscience ; 537: 84-92, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38006961

RESUMO

The endocannabinoid (eCB) system plays an important role in regulating the stress response, including glucocorticoid release and the generation of avoidance behaviour. Its two major ligands, 2-arachidonoylglycerol (2-AG) and N-arachidonoylethanolamine (anandamide; AEA), are dynamically influenced by psychological stress to gate the generation of the stress response and facilitate recovery upon stress termination. Many biological systems exhibit circadian "daily" rhythms, including glucocorticoids and endocannabinoids, and the behavioural and endocrine impact of stress is modulated by the time of day. Nonetheless, most preclinical experiments investigating the interaction between stress and endocannabinoids occur in the light, "inactive" phase. We therefore tested if circadian phase influences stress-induced changes in eCB levels in the hippocampus (HIP), prefrontal cortex (PFC), and amygdala (AMY). Adult male rats were exposed to 15 min swim stress or immediately euthanized, and brains were collected. Testing occurred either early in the light or early in the dark phase of their cycle to compare circadian effects. We found that overall, stress decreased AEA in the AMY and HIP, with an effect in the PFC dependent on the time of day. Conversely, stress increased 2-AG in the AMY, with an effect in the PFC and HIP dependent on the time of day. This suggests that stress has a similar overall impact on eCB levels regardless of circadian phase, but that subtle differences may occur depending on the brain region, especially the PFC.


Assuntos
Tonsila do Cerebelo , Ácidos Araquidônicos , Endocanabinoides , Alcamidas Poli-Insaturadas , Ratos , Animais , Masculino , Endocanabinoides/fisiologia , Glucocorticoides , Córtex Pré-Frontal
17.
Australas Emerg Care ; 27(1): 1-8, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37451885

RESUMO

BACKGROUND: Paramedics experience post-traumatic stress in their work, and many paramedics turn to their intimate partner for support. However, exposure to traumatic event details can leave partners vulnerable to secondary traumatic stress. Despite substantial research into reducing stress and improving support for paramedics, few studies have investigated their partners' trauma experiences and support needs. This scoping review aimed to examine evidence regarding secondary traumatic stress in paramedic partners. METHODS: The MEDLINE, PsychINFO, CINAHL, EMCare, and Sociology Source Ultimate databases were searched up to November 9, 2022. The results sections of studies published in English involving a sample of paramedic partners that examined the impact of paramedics' work-related exposure to trauma on their intimate partner were extracted for analysis. This scoping review was guided by the Joanna Briggs Institute methodology. Key themes were generated using a framework synthesis approach. RESULTS: Five qualitative studies and one quantitative study were included, indicating a paucity of literature regarding secondary traumatic stress in paramedic partners. Post-traumatic stress experienced by paramedics can crossover to paramedic partners in the form of secondary traumatic stress; furthermore, it can have widespread effects on couple functioning. While paramedic partners appear to recognise the need for effective coping strategies, they perceive that little support is available to them. Notably, effective strategies aimed at reducing secondary traumatic stress in paramedic partners are limited. CONCLUSION: Further research is required to quantify secondary traumatic stress severity in paramedic partners and explore relationships between post-traumatic stress, secondary traumatic stress, and couple functioning. Further, evaluation of partner support needs and barriers to accessing support is warranted.


Assuntos
Fadiga de Compaixão , Auxiliares de Emergência , Humanos , Paramédico , Pesquisa Qualitativa
19.
Biol Psychiatry Glob Open Sci ; 4(1): 11-18, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38021250

RESUMO

Background: Cannabis is the most used federally illicit substance among pregnant people in the United States. However, emerging preclinical data show that a significant portion of cannabis constituents, such as Δ9-tetrahydrocannabinol and its bioactive metabolites, readily cross the placenta and accumulate in the fetal brain, disrupting neurodevelopment. Recent research using the Adolescent Brain Cognitive Development (ABCD) Study cohort has linked prenatal cannabis exposure (PCE) to greater neurobehavioral problems and lower total gray and white matter volume in children. Here, we examined the impact of PCE on frontolimbic white matter pathways that are critical for cognitive- and emotion-related functioning, show a high density of cannabinoid receptors, and are susceptible to cannabis exposure during other periods of rapid neurodevelopment (e.g., adolescence). Methods: This study included 11,530 children (mean ± SD age = 118.99 ± 7.49 months; 47% female) from the ABCD Study cohort. Linear mixed-effects models were used to examine the effects of caregiver-reported PCE on fractional anisotropy of 10 frontolimbic pathways (5 per hemisphere). Results: PCE was associated with lower fractional anisotropy of the right (ß = -0.005, p < .001) and left (ß = -0.003, p = .007) fornix, and these results remained significant after adjusting for a variety of covariates, multiple comparisons, fractional anisotropy of all fibers, and using a quality-control cohort only. Conclusions: In sum, we demonstrated small, yet reliable, effects of PCE on white matter integrity during childhood, particularly in the fornix, which plays a crucial role in emotion- and memory-related processes. Future studies are needed to understand the impacts of small changes in brain structure or function on neurodevelopment and risk of neurobehavioral problems.

20.
Ecol Evol ; 13(10): e10564, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37780081

RESUMO

Despite lotic systems demonstrating high levels of seasonal and spatial variability, most research and biomonitoring practices do not consider seasonality when interpreting results and are typically focused at the meso-scale (combined pool/riffle samples) rather than considering habitat patch dynamics. We therefore sought to determine if the sampling season (spring, summer and autumn) influenced observed macroinvertebrate biodiversity, structure and function at the habitat unit scale (determined by substrate composition), and if this in turn influenced the assessment of fine sediment (sand and silt) pressures. We found that biodiversity supported at the habitat level was not seasonally consistent with the contribution of nestedness and turnover in structuring communities varying seasonally. Habitat differences in community composition were evident for taxonomic communities regardless of the season but were not seasonally consistent for functional communities, and, notably, season explained a greater amount of variance in functional community composition than the habitat unit. Macroinvertebrate biodiversity supported by silt habitats demonstrated strong seasonal differences and communities were functionally comparable to sand habitats in spring and to gravel habitats in autumn. Sand communities were impoverished compared to other habitats regardless of the season. Silt habitats demonstrated a strong increase in Ephemeroptera, Plecoptera and Trichoptera (EPT) taxa and functional richness from spring into autumn, while vegetation habitats displayed a peak in EPT abundance in summer. Only silt and sand habitats demonstrated temporal variability in functional evenness suggesting that these habitats are different in terms of their resource partitioning and productivity over time compared to other habitats. Gravel and vegetation habitats appeared to be more stable over time with functional richness and evenness remaining consistent. To accurately evaluate the influence of fine sediment on lotic ecosystems, it is imperative that routine biomonitoring and scientific research discriminate between sand and silt fractions, given they support different biodiversity, particularly during summer and autumn months.

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