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1.
Mol Ecol ; 33(5): e17267, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38230446

RESUMO

The range-expansion of tropical herbivores due to ocean warming can profoundly alter temperate reef communities by overgrazing the seaweed forests that underpin them. Such ecological interactions may be mediated by changes to seaweed-associated microbiota in response to warming, but empirical evidence demonstrating this is rare. We experimentally simulated ocean warming and marine heatwaves (MHWs) to quantify effects on two dominant temperate seaweed species and their microbiota, as well as grazing by a tropical herbivore. The kelp Ecklonia radiata's microbiota in sustained warming and MHW treatments was enriched with microorganisms associated with seaweed disease and tissue degradation. In contrast, the fucoid Sargassum linearifolium's microbiota was unaffected by temperature. Consumption by the tropical sea-urchin Tripneustes gratilla was greater on Ecklonia where the microbiota had been altered by higher temperatures, while Sargassum's consumption was unaffected. Elemental traits (carbon, nitrogen), chemical defences (phenolics) and tissue bleaching of both seaweeds were generally unaffected by temperature. Effects of warming and MHWs on seaweed holobionts (host plus its microbiota) are likely species-specific. The effect of increased temperature on Ecklonia's microbiota and subsequent increased consumption suggest that changes to kelp microbiota may underpin kelp-herbivore interactions, providing novel insights into potential mechanisms driving change in species' interactions in warming oceans.


Assuntos
Kelp , Microbiota , Alga Marinha , Kelp/fisiologia , Ecossistema , Mudança Climática , Oceanos e Mares
2.
Mol Ecol ; 31(7): 2189-2206, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35104026

RESUMO

Interactions between hosts and their microbiota are vital to the functioning and resilience of macro-organisms. Critically, for hosts that play foundational roles in communities, understanding what drives host-microbiota interactions is essential for informing ecosystem restoration and conservation. We investigated the relative influence of host traits and the surrounding environment on microbial communities associated with the foundational seaweed Phyllospora comosa. We quantified 16 morphological and functional phenotypic traits, including host genetics (using 354 single nucleotide polymorphisms) and surface-associated microbial communities (using 16S rRNA gene amplicon sequencing) from 160 individuals sampled from eight sites spanning Phyllospora's entire latitudinal distribution (1,300 km). Combined, these factors explained 54% of the overall variation in Phyllospora's associated microbial community structure, much of which was related to the local environment (~32%). We found that putative "core" microbial taxa (i.e., present on all Phyllospora individuals sampled) exhibited slightly higher associations with host traits when compared to "variable" taxa (not present on all individuals). We identified several key genetic loci and phenotypic traits in Phyllospora that were strongly related to multiple microbial amplicon sequence variants, including taxa with known associations to seaweed defence, disease and tissue degradation. This information on how host-associated microbial communities vary with host traits and the environment enhances our current understanding of how "holobionts" (hosts plus their microbiota) are structured. Such understanding can be used to inform management strategies of these important and vulnerable habitats.


Assuntos
Microbiota , Phaeophyceae , Alga Marinha , Geografia , Microbiota/genética , Phaeophyceae/genética , Fenótipo , RNA Ribossômico 16S/genética , Alga Marinha/genética
3.
Glob Chang Biol ; 27(10): 2200-2212, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33511779

RESUMO

Globally, critical habitats are in decline, threatening ecological, economic and social values and prompting calls for 'future proofing' efforts that enhance resilience to climate change. Such efforts rely on predicting how neutral and adaptive genomic patterns across a species' distribution will change under future climate scenarios, but data is scant for most species of conservation concern. Here, we use seascape genomics to characterise genetic diversity, structure and gene-environmental associations in a dominant forest-forming seaweed, Phyllospora comosa, along its entire latitudinal (12° latitude), and thermal (~14°C) range. Phyllospora showed high connectivity throughout its central range, with evidence of genetic structure and potential selection associated with sea surface temperatures (SSTs) at its rear and leading edges. Rear and leading-edge populations harboured only half the genetic diversity of central populations. By modelling genetic turnover as a function of SST, we assessed the genomic vulnerability across Phyllospora's distributional range under climate change scenarios. Despite low diversity, range-edge populations were predicted to harbour beneficial adaptations to marginal conditions and overall adaptability of the species may be compromised by their loss. Assisted gene flow from range edge populations may be required to enhance adaptation and increase resilience of central and leading-edge populations under warming oceans. Understanding genomic vulnerability can inform proactive restoration and future-proofing strategies for underwater forests and ensure their persistence in changing oceans.


Assuntos
Alga Marinha , Austrália , Mudança Climática , Florestas , Genômica , Oceanos e Mares
4.
Fish Shellfish Immunol ; 113: 176-184, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33823246

RESUMO

Disease is one of the major bottlenecks for aquaculture development, costing the industry in excess of US $6 billion each year. The increase in pressure to phase out some traditional approaches to disease control (e.g. antibiotics) is pushing farmers to search for alternatives to treat and prevent disease outbreaks, which do not have detrimental consequences (e.g. antibiotic resistance). We tested the effects of eleven seaweed species and four established fish immunostimulants on the innate immune response (cellular and humoral immunity) of the rabbitfish Siganus fuscescens. All supplements including different seaweeds from the three groups (Chlorophyta, Phaeophyta and Rhodophyta) were included in the fish pellet at 3% (by weight) and had variably positive effects across the four innate immune parameters we measured compared to control fish. Diets supplemented with the red seaweed Asparagopsis taxiformis and the brown seaweed Dictyota intermedia led to the largest boosts in humoral and cellular innate immune defences, including particularly significant increases in haemolytic activity. Diets supplemented with Ulva fasciata also led to promising positive effects on the fish innate immune responses. We conclude that dietary seaweed supplements can boost the immune response of S. fuscescens and thus the top three species highlighted in this study should be further investigated for this emerging aquaculture species and other fish species.


Assuntos
Ração Animal/análise , Clorófitas/química , Imunidade Inata/efeitos dos fármacos , Perciformes/imunologia , Phaeophyceae/química , Rodófitas/química , Alga Marinha/química , Animais , Dieta/veterinária , Suplementos Nutricionais/análise
5.
J Phycol ; 57(5): 1504-1516, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33942303

RESUMO

Infectious diseases affecting habitat-forming species can have significant impacts on population dynamics and alter the structure and functioning of marine ecosystems. Recently, a fungal infection was described as the causative agent of necrotic lesions on the stipe of the forest-forming macroalga Phyllospora comosa, a disease named "stipe rot" (SR). Here, we developed a quantitative PCR (qPCR) method for rapid detection and quantification of this pathogen, which was applied to evaluate the level of SR infection in eight P. comosa populations spanning the entire latitudinal distribution of this species along southeastern Australia. We also investigated the relationship between the abundance and prevalence of Stipe Rot Fungus (SRF) and potential host chemical defenses as well as its relationship with morphological and ecophysiological traits of P. comosa. qPCR estimates of SRF abundance reflected the levels of infection estimated by visual assessment, with higher numbers of SRF copies being observed in individuals showing high or intermediate levels of visual symptoms of SR. Concordance of conventional PCR and visual assessments was 92 and 94%, respectively, compared to qPCR detection. SRF prevalence was positively related to fucoxanthin content and herbivory, but not significant related to other traits measured (phlorotannin content, total length, thallus diameter, stipe width, number of branches, frond width, fouling, bleaching, gender, and photosynthetic efficiency). These results provide confidence for previous reports of this disease based upon visual assessments only, contribute to the development of monitoring and conservation strategies for safeguarding P. comosa forests, and generate insights into potential factors influencing host-pathogen interactions in this system.


Assuntos
Fungos/patogenicidade , Phaeophyceae , Alga Marinha , Ecossistema , Herbivoria , Phaeophyceae/microbiologia , Alga Marinha/microbiologia
6.
J Chem Inf Model ; 60(3): 1749-1765, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-32078320

RESUMO

Ergotamine (ERG) and dihydroergotamine (DHE), common migraine drugs, have small structural differences but lead to clinically important distinctions in their pharmacological profiles. For example, DHE is less potent than ERG by about 10-fold at the 5-hydroxytrptamine receptor 1B (5-HT1B). Although the high-resolution crystal structures of the 5-HT1B receptor with both ligands have been solved, the high similarity between these two complex structures does not sufficiently explain their activity differences and the activation mechanism of the receptor. Hence, an examination of the dynamic motion of both drugs with the receptor is required. In this study, we ran a total of 6.0 µs molecular dynamics simulations on each system. Our simulation data show the subtle variations between the two systems in terms of the ligand-receptor interactions and receptor secondary structures. More importantly, the ligand and protein root-mean-square fluctuations (RMSFs) for the two systems were distinct, with ERG having a trend of lower RMSF values, indicating it to be bound tighter to 5-HT1B with less fluctuations. The molecular mechanism-general born surface area (MM-GBSA) binding energies illustrate this further, proving ERG has an overall stronger MM-GBSA binding energy. Analysis of several different microswitches has shown that the 5-HT1B-ERG complex is in a more active conformation state than 5-HT1B-DHE, which is further supported by the dynamic network model, with reference to mutagenesis data with the critical nodes and the first three low-energy modes from the normal mode analysis. We also identify Trp3276.48 and Phe3316.52 as key residues involved in the active state 5-HT1B for both ligands. Using the detailed dynamic information from our analysis, we made predictions for possible modifications to DHE and ERG that yielded five derivatives that might have more favorable binding energies and reduced structural fluctuations.


Assuntos
Di-Hidroergotamina , Ergotamina , Simulação de Dinâmica Molecular , Receptores de Serotonina , Serotonina
7.
Proc Biol Sci ; 286(1896): 20181887, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30963929

RESUMO

Climate change is driving global declines of marine habitat-forming species through physiological effects and through changes to ecological interactions, with projected trajectories for ocean warming and acidification likely to exacerbate such impacts in coming decades. Interactions between habitat-formers and their microbiomes are fundamental for host functioning and resilience, but how such relationships will change in future conditions is largely unknown. We investigated independent and interactive effects of warming and acidification on a large brown seaweed, the kelp Ecklonia radiata, and its associated microbiome in experimental mesocosms. Microbial communities were affected by warming and, during the first week, by acidification. During the second week, kelp developed disease-like symptoms previously observed in the field. The tissue of some kelp blistered, bleached and eventually degraded, particularly under the acidification treatments, affecting photosynthetic efficiency. Microbial communities differed between blistered and healthy kelp for all treatments, except for those under future conditions of warming and acidification, which after two weeks resembled assemblages associated with healthy hosts. This indicates that changes in the microbiome were not easily predictable as the severity of future climate scenarios increased. Future ocean conditions can change kelp microbiomes and may lead to host disease, with potentially cascading impacts on associated ecosystems.


Assuntos
Mudança Climática , Kelp/fisiologia , Microbiota , Água do Mar/química , Ecossistema , Aquecimento Global , Concentração de Íons de Hidrogênio , Kelp/microbiologia
8.
Proc Natl Acad Sci U S A ; 113(48): 13791-13796, 2016 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-27849585

RESUMO

Some of the most profound effects of climate change on ecological communities are due to alterations in species interactions rather than direct physiological effects of changing environmental conditions. Empirical evidence of historical changes in species interactions within climate-impacted communities is, however, rare and difficult to obtain. Here, we demonstrate the recent disappearance of key habitat-forming kelp forests from a warming tropical-temperate transition zone in eastern Australia. Using a 10-y video dataset encompassing a 0.6 °C warming period, we show how herbivory increased as kelp gradually declined and then disappeared. Concurrently, fish communities from sites where kelp was originally abundant but subsequently disappeared became increasingly dominated by tropical herbivores. Feeding assays identified two key tropical/subtropical herbivores that consumed transplanted kelp within hours at these sites. There was also a distinct increase in the abundance of fishes that consume epilithic algae, and much higher bite rates by this group at sites without kelp, suggesting a key role for these fishes in maintaining reefs in kelp-free states by removing kelp recruits. Changes in kelp abundance showed no direct relationship to seawater temperatures over the decade and were also unrelated to other measured abiotic factors (nutrients and storms). Our results show that warming-mediated increases in fish herbivory pose a significant threat to kelp-dominated ecosystems in Australia and, potentially, globally.


Assuntos
Ecossistema , Peixes/fisiologia , Kelp/crescimento & desenvolvimento , Oceanos e Mares , Animais , Austrália , Mudança Climática , Cadeia Alimentar , Herbivoria/fisiologia , Temperatura , Clima Tropical
10.
Environ Microbiol ; 17(10): 4078-88, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26148974

RESUMO

Interactions between hosts and associated microbial communities can fundamentally shape the development and ecology of 'holobionts', from humans to marine habitat-forming organisms such as seaweeds. In marine systems, planktonic microbial community structure is mainly driven by geography and related environmental factors, but the large-scale drivers of host-associated microbial communities are largely unknown. Using 16S-rRNA gene sequencing, we characterized 260 seaweed-associated bacterial and archaeal communities on the kelp Ecklonia radiata from three biogeographical provinces spanning 10° of latitude and 35° of longitude across the Australian continent. These phylogenetically and taxonomically diverse communities were more strongly and consistently associated with host condition than geographical location or environmental variables, and a 'core' microbial community characteristic of healthy kelps appears to be lost when hosts become stressed. Microbial communities on stressed individuals were more similar to each other among locations than those on healthy hosts. In contrast to biogeographical patterns of planktonic marine microbial communities, host traits emerge as critical determinants of associated microbial community structure of these holobionts, even at a continental scale.


Assuntos
Archaea/classificação , Bactérias/classificação , Kelp/microbiologia , Microbiota/genética , Plâncton/microbiologia , Archaea/genética , Austrália , Bactérias/genética , Ecossistema , Meio Ambiente , Geografia , Humanos , Microbiota/fisiologia , Fenótipo , Filogenia , RNA Ribossômico 16S/genética
11.
Proc Biol Sci ; 281(1789): 20140846, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25009065

RESUMO

Climate-driven changes in biotic interactions can profoundly alter ecological communities, particularly when they impact foundation species. In marine systems, changes in herbivory and the consequent loss of dominant habitat forming species can result in dramatic community phase shifts, such as from coral to macroalgal dominance when tropical fish herbivory decreases, and from algal forests to 'barrens' when temperate urchin grazing increases. Here, we propose a novel phase-shift away from macroalgal dominance caused by tropical herbivores extending their range into temperate regions. We argue that this phase shift is facilitated by poleward-flowing boundary currents that are creating ocean warming hotspots around the globe, enabling the range expansion of tropical species and increasing their grazing rates in temperate areas. Overgrazing of temperate macroalgae by tropical herbivorous fishes has already occurred in Japan and the Mediterranean. Emerging evidence suggests similar phenomena are occurring in other temperate regions, with increasing occurrence of tropical fishes on temperate reefs.


Assuntos
Mudança Climática , Ecossistema , Herbivoria , Animais , Organismos Aquáticos , Biodiversidade , Peixes , Modelos Biológicos , Alga Marinha
12.
Ecology ; 95(1): 142-52, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24649654

RESUMO

Diseases affecting natural ecosystems are increasing in frequency and severity, but unless obviously catastrophic, the consequences of disease outbreaks are often overlooked, relative to other ecological processes (e.g., predation, competition). Disease can have profound effects on individuals and can also strongly influence interactions between infected hosts and their natural enemies. We investigated whether a novel bleaching disease affected the survival or performance of a habitat-forming red seaweed, Delisea pulchra. In addition, we investigated bidirectional, multipartite interactions between this seaweed host, its pathogens, and consumers. Although we found no negative impacts of disease on survival of D. pulchra, bleaching had substantial, negative consequences for affected individuals, including a dramatic drop in fecundity and a significant decrease in size. In the first direct demonstration of bacterial disease-mediated herbivory of seaweeds, herbivores generally preferred to consume bleached tissue in feeding trials, and we also found higher densities of herbivores on bleached than co-occurring, healthy algae at sites where herbivores were abundant. In a conceptually reciprocal test of the effects of herbivores on infection, we showed that simulated herbivory increased susceptibility to bleaching when algae were also exposed to cultures of a bacterial pathogen. Given the high proportions of D. pulchra affected by bleaching during peak periods, the impacts of this disease are likely to have important implications at the population level. This work highlights complex interactions between habitat-forming organisms and their natural enemies and further emphasizes the need to consider disease in ecological research.


Assuntos
Ecossistema , Rodófitas/fisiologia , Alga Marinha , Animais , Herbivoria , Invertebrados/fisiologia , Doenças das Plantas , Dinâmica Populacional
13.
J Trauma Acute Care Surg ; 96(3): 386-393, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37934622

RESUMO

BACKGROUND: Succinate is a proinflammatory citric acid cycle metabolite that accumulates in tissues during pathophysiological states. Oxidation of succinate after ischemia-reperfusion leads to reversal of the electron transport chain and generation of reactive oxygen species. Dimethyl malonate (DMM) is a competitive inhibitor of succinate dehydrogenase, which has been shown to reduce succinate accumulation. We hypothesized that DMM would protect against inflammation in a murine model of ARDS. METHODS: C57BL/6 mice were given ARDS via 67.7 µg of intratracheally administered lipopolysaccharide. Dimethyl malonate (50 mg/kg) was administered via tail vein injection 30 minutes after injury, then daily for 3 days. The animals were sacrificed on day 4 after bronchoalveolar lavage (BAL). Bronchoalveolar lavage cell counts were performed to examine cellular influx. Supernatant protein was quantified via Bradford protein assay. Animals receiving DMM (n = 8) were compared with those receiving sham injection (n = 8). Cells were fixed and stained with FITC-labeled wheat germ agglutinin to quantify the endothelial glycocalyx (EGX). RESULTS: Total cell counts in BAL was less for animals receiving DMM (6.93 × 10 6 vs. 2.46 × 10 6 , p = 0.04). The DMM group had less BAL macrophages (168.6 vs. 85.1, p = 0.04) and lymphocytes (527.7 vs. 248.3; p = 0.04). Dimethyl malonate-treated animals had less protein leak in BAL than sham treated (1.48 vs. 1.15 µg/µl, p = 0.03). Treatment with DMM resulted in greater staining intensity of the EGX in the lung when compared with sham (12,016 vs. 15,186 arbitrary units, p = 0.03). Untreated animals had a greater degree of weight loss than treated animals (3.7% vs. 1.1%, p = 0.04). Dimethyl malonate prevented the upregulation of monocyte chemoattractant protein-1 (1.66 vs. 0.92 RE, p = 0.02) and ICAM-1 (1.40 vs. 1.01 RE, p = 0.05). CONCLUSION: Dimethyl malonate reduces lung inflammation and capillary leak in ARDS. This may be mediated by protection of the EGX and inhibition of monocyte chemoattractant protein-1 and ICAM-1. Dimethyl malonate may be a novel therapeutic for ARDS.


Assuntos
Quimiocina CCL2 , Malonatos , Síndrome do Desconforto Respiratório , Camundongos , Animais , Molécula 1 de Adesão Intercelular , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Pulmão/metabolismo , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/prevenção & controle , Succinatos
14.
J Trauma Acute Care Surg ; 97(1): 32-38, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38444065

RESUMO

INTRODUCTION: The endothelial glycocalyx on the luminal surface of endothelial cells contributes to the permeability barrier of the pulmonary vasculature. Dimethyl sulfoxide (DMSO) has a disordering effect on plasma membranes, which prevents the formation of ordered membrane domains important in the shedding of the endothelial glycocalyx. We hypothesized that DMSO would protect against protein leak by preserving the endothelial glycocalyx in a murine model of acute respiratory distress syndrome (ARDS). METHODS: C57BL/6 mice were given ARDS via intratracheally administered lipopolysaccharide (LPS). Dimethyl sulfoxide (220 mg/kg) was administered intravenously for 4 days. Animals were sacrificed postinjury day 4 after bronchoalveolar lavage (BAL). Bronchoalveolar lavage cell counts and protein content were quantified. Lung sections were stained with fluorescein isothiocyanate-labeled wheat germ agglutinin to quantify the endothelial glycocalyx. Human umbilical vein endothelial cells (HUVECs) were exposed to LPS. Endothelial glycocalyx was measured using fluorescein isothiocyanate-labeled wheat germ agglutinin, and co-immunoprecipitation was performed to measure interaction between sheddases and syndecan-1. RESULTS: Dimethyl sulfoxide treatment resulted in greater endothelial glycocalyx staining intensity in the lung when compared with sham (9,641 vs. 36,659 arbitrary units, p < 0.001). Total BAL cell counts were less for animals receiving DMSO (6.93 × 10 6 vs. 2.49 × 10 6 cells, p = 0.04). The treated group had less BAL macrophages (189.2 vs. 76.9 cells, p = 0.02) and lymphocytes (527.7 vs. 200.0 cells, p = 0.02). Interleukin-6 levels were lower in DMSO treated. Animals that received DMSO had less protein leak in BAL (1.48 vs. 1.08 µg/µL, p = 0.02). Dimethyl sulfoxide prevented LPS-induced endothelial glycocalyx loss in HUVECs and reduced the interaction between matrix metalloproteinase 16 and syndecan-1. CONCLUSION: Systemically administered DMSO protects the endothelial glycocalyx in the pulmonary vasculature, mitigating pulmonary capillary leak after acute lung injury. Dimethyl sulfoxide also results in decreased inflammatory response. Dimethyl sulfoxide reduced the interaction between matrix metalloproteinase 16 and syndecan-1 and prevented LPS-induced glycocalyx damage in HUVECs. Dimethyl sulfoxide may be a novel therapeutic for ARDS.


Assuntos
Lesão Pulmonar Aguda , Dimetil Sulfóxido , Modelos Animais de Doenças , Glicocálix , Camundongos Endogâmicos C57BL , Animais , Camundongos , Glicocálix/metabolismo , Glicocálix/efeitos dos fármacos , Dimetil Sulfóxido/farmacologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Lipopolissacarídeos , Masculino , Humanos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/patologia , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos
15.
Clin Rheumatol ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853226

RESUMO

The purpose of this study was to conduct a scoping review to describe the evidence on the efficacy and safety of using cannabis-based medicines for osteoarthritis. The review was conducted following the framework proposed by Arksey and O'Malley and reported following PRISMA extension for scoping reviews guidelines. We conducted a comprehensive search across various databases including MEDLINE, Embase, Cochrane Library, CINAHL, Scopus, and Proquest, spanning from inception of each database to March 2023. We retrieved 2533 citations, and after deduplication, title and abstract screening, and full-text screening, 10 articles were included for analysis. These studies were composed of randomized-controlled trials (n = 4/10), cross-sectional surveys (n = 3/10), case studies (n = 2/10), and a cohort study (n = 1/10). Evidence for using cannabis-based medicines was mixed, with just 60% (n = 6/10) of included studies reporting statistically significant improvements in pain. Studies with larger samples sizes and longer durations of exposure did not find significant benefits for pain. The few adverse effects reported were generally mild and affected a minority of participants. Several studies also discovered that cannabis-based medicines were associated with a reduction in opioid use. Currently available data on the use of cannabis-based medicines in osteoarthritis is insufficient to make recommendations. Future research should address concerns regarding small sample sizes and short treatment durations to provide a more robust evidence base. Key Points • Current evidence remains mixed; studies that found a positive benefit with using cannabis-based medicines had limitations with small sample sizes and short durations of exposure • The use of cannabis-based medicines in osteoarthritis appears to be generally well tolerated, adverse effects are mild and experienced by a minority of participants • Cannabis-based medicines may decrease the use of opioids in patients with osteoarthritis • Future research should address the gaps in long-term efficacy and safety data.

16.
Transl Psychiatry ; 14(1): 70, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38296944

RESUMO

Suicide attempt (SA) risk is elevated in individuals with bipolar disorder (BD), and DNA methylation patterns may serve as possible biomarkers of SA. We conducted epigenome-wide association studies (EWAS) of blood DNA methylation associated with BD and SA. DNA methylation was measured at >700,000 positions in a discovery cohort of n = 84 adults with BD with a history of SA (BD/SA), n = 79 adults with BD without history of SA (BD/non-SA), and n = 76 non-psychiatric controls (CON). EWAS revealed six differentially methylated positions (DMPs) and seven differentially methylated regions (DMRs) between BD/SA and BD/non-SA, with multiple immune-related genes implicated. There were no epigenome-wide significant differences when BD/SA and BD/non-SA were each compared to CON, and patterns suggested that epigenetics differentiating BD/SA from BD/non-SA do not differentiate BD/non-SA from CON. Weighted gene co-methylation network analysis and trait enrichment analysis of the BD/SA vs. BD/non-SA contrast further corroborated immune system involvement, while gene ontology analysis implicated calcium signalling. In an independent replication cohort of n = 48 BD/SA and n = 47 BD/non-SA, fold changes at the discovery cohort's significant sites showed moderate correlation across cohorts and agreement on direction. In both cohorts, classification accuracy for SA history among individuals with BD was highest when methylation at the significant CpG sites as well as information from clinical interviews were combined, with an AUC of 88.8% (CI = 83.8-93.8%) and 82.1% (CI = 73.6-90.5%) for the combined epigenetic-clinical classifier in the discovery and replication cohorts, respectively. Our results provide novel insight to the role of immune system functioning in SA and BD and also suggest that integrating information from multiple levels of analysis holds promise to improve risk assessment for SA in adults with BD.


Assuntos
Transtorno Bipolar , Adulto , Humanos , Transtorno Bipolar/genética , Epigenoma , Tentativa de Suicídio , Estudo de Associação Genômica Ampla , Epigênese Genética , Metilação de DNA
17.
Mol Ecol ; 22(8): 2280-91, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23517352

RESUMO

Over the last few decades, advances in molecular techniques have led to the detection of strong geographic population structure and cryptic speciation in many benthic marine taxa, even those with long-lived pelagic larval stages. Polychaete annelids, in particular, generally show a high degree of population divergence, especially in mitochondrial genes. Rarely have molecular studies confirmed the presence of 'cosmopolitan' species. The amphinomid polychaete Hermodice carunculata was long considered the sole species within its genus, with a reported distribution throughout the Atlantic and adjacent basins. However, recent studies have indicated morphological differences, primarily in the number of branchial filaments, between the East and West Atlantic populations; these differences were invoked to re-instate Hermodice nigrolineata, formerly considered a junior synonym of H. carunculata. We utilized sequence data from two mitochondrial (cytochrome c oxidase subunit I, 16S rDNA) markers and one nuclear (internal transcribed spacer) marker to examine the genetic diversity of Hermodice throughout its distribution range in the Atlantic Ocean, including the Mediterranean Sea, the Caribbean Sea, the Gulf of Mexico and the Gulf of Guinea. Our analyses revealed generally low genetic divergences among collecting localities and between the East and West Atlantic, although phylogenetic trees based on mitochondrial data indicate the presence of a private lineage in the Mediterranean Sea. A re-evaluation of the number of branchial filaments confirmed differences between East and West Atlantic populations; however, the differences were not diagnostic and did not reflect the observed genetic population structure. Rather, we suspect that the number of branchial filaments is a function of oxygen saturation in the environment. Our results do not support the distinction between H. carunculata in the West Atlantic and H. nigrolineata in the East Atlantic. Instead, they re-affirm the older notion that H. carunculata is a cohesive species with a broad distribution across the Atlantic Ocean.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Poliquetos/genética , RNA Ribossômico 16S/genética , Animais , Oceano Atlântico , Evolução Molecular , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
18.
Chiropr Man Therap ; 31(1): 23, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525206

RESUMO

BACKGROUND: Low back and neck pain are common in the general population, but the prevalence among Canadian post-secondary students is not well known. We aimed to determine the one-week prevalence of neck pain (NP) and low back pain (LBP) among postsecondary students in Canada. METHODS: We conducted a cross-sectional study of students enrolled in the Faculty of Health Sciences and Faculty of Education at Ontario Tech University, and the Canadian Memorial Chiropractic College (CMCC) in the Fall of 2017. Neck and low back pain intensity in the past week were measured with the 11-point numerical rating scale. We report the cumulative, gender- and institution-specific one-week prevalence (95% CI) of any pain (1-10/10) and moderate to severe pain (≥ 3/10). RESULTS: The one-week prevalence of any neck pain ranged from 45.4% (95% CI: 38.4, 52.4) in the Faculty of Education to 76.9% (95% CI: 72.9, 80.4) at CMCC. The one-week prevalence of neck pain ≥3/10 ranged from 44.4% (95% CI: 37.5, 51.4) in the Faculty of Education to 58.4% (95% CI: 54.0, 62.7) at CMCC. The one-week prevalence of any low back pain ranged from 60.9% (95% CI: 53.8, 67.5) in the Faculty of Education to 69.0% (95% CI: 64.8, 73.0) at CMCC, and the one-week prevalence of low back pain ≥ 3/10 ranged from 47.8% (95% CI: 43.4, 52.2) at CMCC to 55.1% (95% CI: 51.2, 58.9) in the Faculty of Health Sciences. The prevalence of any back or neck pain and pain ≥ 3/10 was consistently higher in females than males, with the largest difference seen for neck pain at CMCC. CONCLUSION: Most post-secondary students in our samples experienced LBP and NP in the past week. Overall, the one-week prevalence of NP and LBP was higher among chiropractic students and among females. This study should draw attention to school administrators about the burden of NP and LBP in post-secondary students.


Assuntos
Dor Lombar , Masculino , Feminino , Humanos , Dor Lombar/epidemiologia , Cervicalgia/epidemiologia , Prevalência , Estudos Transversais , Estudantes , Ontário/epidemiologia
19.
Disabil Rehabil ; 45(22): 3783-3787, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36262023

RESUMO

Aim: Despite efforts towards a more just culture, rehabilitation providers still experience shame and trauma when their patients fall. This paper proposes a shift in philosophy in how we classify, communicate and learn from falls, and joins the growing literature in which falls in rehab are not seen as something to be avoided at all costs, but rather as part of the recovery journey for some patients.Methods: Patients who understand and are willing to take on the risks of falling are more likely to collaborate with their care team to practice higher-risk activities, such as walking to the bathroom independently at night, as part of their recovery. If a fall takes place in this context, we argue that it should be considered a "therapeutic" fall.Results: This paper details some of the clinical and ethical approaches to supporting a care environment where values-and potential conflicts-about the benefits and challenges of risk-taking are recognized. An expanded concept of a therapeutic fall may help patients and providers take a more balanced and nuanced approach to promoting safety while maximising independence.Conclusion: The goal of this work is to offer rehabilitation patients greater opportunities to make autonomous decisions about their mobility, and lay the groundwork for a more successful transition home.IMPLICATIONS FOR REHABILITATIONDespite best efforts, patients are often less active than they or their rehabilitation team might wish them to be.An expanded concept of a "therapeutic" fall may help patients and providers take a more balanced and nuanced approach to promoting safety while maximising independence.Rehabilitation is the right environment to support shared decision-making about risk that better prepares patients and families for the often challenging transition back to community living.This works represents a shift in philosophy in how we classify, communicate and learn from falls, and joins the growing literature in which falls are not something to be avoided at all costs, but can instead be part of the journey to recovery.

20.
Disaster Med Public Health Prep ; 17: e473, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37650226

RESUMO

OBJECTIVE: The effects of named weather storms on the rates of penetrating trauma is poorly understood with only case reports of single events currently guiding public health policy. This study examines whether tropical storms and hurricanes contribute to trauma services and volume. METHODS: This was a cross-sectional review of tropical storms/hurricanes affecting New Orleans, Louisiana, during hurricane seasons (June 1-November 30) from 2010-2021, and their association with the rate of penetrating trauma. Authors sought to determine how penetrating trauma rates changed during hurricane seasons and associate them with demographic variables. RESULTS: There were 5531 penetrating injuries, with 412 (7.4%) occurring during landfall and 554 (10.0%) in the aftermath. Black/African Americans were the most affected. There was an increase in the rate of penetrating events during landfall (3.4 events/day) and aftermath (3.5 events/day) compared to the baseline (2.8 events/day) (P = < 0.001). Using multivariate analysis, wind speed was positively related to firearm injury, whereas the rainfall total was inversely related to firearm violence rates during landfall and aftermath periods. Self-harm was positively related to distance from the trauma center. CONCLUSIONS: Cities at risk for named weather storms may face increasing gun violence in the landfall and aftermath periods. Black/African Americans are most affected, worsening existing disparities. Self-harm may also increase following these weather events.


Assuntos
Tempestades Ciclônicas , Armas de Fogo , Ferimentos por Arma de Fogo , Humanos , Nova Orleans/epidemiologia , Estudos Transversais
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