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Increasingly frequent marine heatwaves are devastating coral reefs. Corals that survive these extreme events must rapidly recover if they are to withstand subsequent events, and long-term survival in the face of rising ocean temperatures may hinge on recovery capacity and acclimatory gains in heat tolerance over an individual's lifespan. To better understand coral recovery trajectories in the face of successive marine heatwaves, we monitored the responses of bleaching-susceptible and bleaching-resistant individuals of two dominant coral species in Hawai'i, Montipora capitata and Porites compressa, over a decade that included three marine heatwaves. Bleaching-susceptible colonies of P. compressa exhibited beneficial acclimatization to heat stress (i.e., less bleaching) following repeat heatwaves, becoming indistinguishable from bleaching-resistant conspecifics during the third heatwave. In contrast, bleaching-susceptible M. capitata repeatedly bleached during all successive heatwaves and exhibited seasonal bleaching and substantial mortality for up to 3 y following the third heatwave. Encouragingly, bleaching-resistant individuals of both species remained pigmented across the entire time series; however, pigmentation did not necessarily indicate physiological resilience. Specifically, M. capitata displayed incremental yet only partial recovery of symbiont density and tissue biomass across both bleaching phenotypes up to 35 mo following the third heatwave as well as considerable partial mortality. Conversely, P. compressa appeared to recover across most physiological metrics within 2 y and experienced little to no mortality. Ultimately, these results indicate that even some visually robust, bleaching-resistant corals can carry the cost of recurring heatwaves over multiple years, leading to divergent recovery trajectories that may erode coral reef resilience in the Anthropocene.
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Antozoários , Humanos , Animais , Antozoários/fisiologia , Recifes de Corais , Temperatura , Aclimatação/fisiologia , BiomassaRESUMO
Metabolites exuded by primary producers comprise a significant fraction of marine dissolved organic matter, a poorly characterized, heterogenous mixture that dictates microbial metabolism and biogeochemical cycling. We present a foundational untargeted molecular analysis of exudates released by coral reef primary producers using liquid chromatography-tandem mass spectrometry to examine compounds produced by two coral species and three types of algae (macroalgae, turfing microalgae, and crustose coralline algae [CCA]) from Mo'orea, French Polynesia. Of 10,568 distinct ion features recovered from reef and mesocosm waters, 1,667 were exuded by producers; the majority (86%) were organism specific, reflecting a clear divide between coral and algal exometabolomes. These data allowed us to examine two tenets of coral reef ecology at the molecular level. First, stoichiometric analyses show a significantly reduced nominal carbon oxidation state of algal exometabolites than coral exometabolites, illustrating one ecological mechanism by which algal phase shifts engender fundamental changes in the biogeochemistry of reef biomes. Second, coral and algal exometabolomes were differentially enriched in organic macronutrients, revealing a mechanism for reef nutrient-recycling. Coral exometabolomes were enriched in diverse sources of nitrogen and phosphorus, including tyrosine derivatives, oleoyl-taurines, and acyl carnitines. Exometabolites of CCA and turf algae were significantly enriched in nitrogen with distinct signals from polyketide macrolactams and alkaloids, respectively. Macroalgal exometabolomes were dominated by nonnitrogenous compounds, including diverse prenol lipids and steroids. This study provides molecular-level insights into biogeochemical cycling on coral reefs and illustrates how changing benthic cover on reefs influences reef water chemistry with implications for microbial metabolism.
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Antozoários/metabolismo , Matéria Orgânica Dissolvida/análise , Alga Marinha/metabolismo , Animais , Antozoários/genética , Antozoários/crescimento & desenvolvimento , Carbono/metabolismo , Recifes de Corais , Ecossistema , Biologia Marinha/métodos , Metabolômica/métodos , Nitrogênio/metabolismo , Nutrientes , Fósforo/metabolismo , Polinésia , Água do Mar/química , Alga Marinha/genética , Alga Marinha/crescimento & desenvolvimentoRESUMO
Microbes are found in nearly every habitat and organism on the planet, where they are critical to host health, fitness, and metabolism. In most organisms, few microbes are inherited at birth; instead, acquiring microbiomes generally involves complicated interactions between the environment, hosts, and symbionts. Despite the criticality of microbiome acquisition, we know little about where hosts' microbes reside when not in or on hosts of interest. Because microbes span a continuum ranging from generalists associating with multiple hosts and habitats to specialists with narrower host ranges, identifying potential sources of microbial diversity that can contribute to the microbiomes of unrelated hosts is a gap in our understanding of microbiome assembly. Microbial dispersal attenuates with distance, so identifying sources and sinks requires data from microbiomes that are contemporary and near enough for potential microbial transmission. Here, we characterize microbiomes across adjacent terrestrial and aquatic hosts and habitats throughout an entire watershed, showing that the most species-poor microbiomes are partial subsets of the most species-rich and that microbiomes of plants and animals are nested within those of their environments. Furthermore, we show that the host and habitat range of a microbe within a single ecosystem predicts its global distribution, a relationship with implications for global microbial assembly processes. Thus, the tendency for microbes to occupy multiple habitats and unrelated hosts enables persistent microbiomes, even when host populations are disjunct. Our whole-watershed census demonstrates how a nested distribution of microbes, following the trophic hierarchies of hosts, can shape microbial acquisition.
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Ecossistema , Microbiota , Plantas , Animais , Bactérias , Plantas/microbiologiaRESUMO
Hoarding disorder (HD) is a debilitating neuropsychiatric condition that affects 2%-6% of the population and increases in incidence with age. Major depressive disorder (MDD) co-occurs with HD in approximately 50% of cases and leads to increased functional impairment and disability. However, only one study to date has examined the rate and trajectory of hoarding symptoms in older individuals with a lifetime history of MDD, including those with current active depression (late-life depression; LLD). We therefore sought to characterize this potentially distinct phenotype. We determined the incidence of HD in two separate cohorts of participants with LLD (n = 73) or lifetime history of MDD (n = 580) and examined the reliability and stability of hoarding symptoms using the Saving Inventory-Revised (SI-R) and Hoarding Rating Scale-Self Report (HRS), as well as the co-variance of hoarding and depression scores over time. HD was present in 12% to 33% of participants with MDD, with higher rates found in those with active depressive symptoms. Hoarding severity was stable across timepoints in both samples (all correlations >0.75), and fewer than 30% of participants in each sample experienced significant changes in severity between any two timepoints. Change in depression symptoms over time did not co-vary with change in hoarding symptoms. These findings indicate that hoarding is a more common comorbidity in LLD than previously suggested, and should be considered in screening and management of LLD. Future studies should further characterize the interaction of these conditions and their impact on outcomes, particularly functional impairment in this vulnerable population.
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Transtorno Depressivo Maior , Transtorno de Acumulação , Colecionismo , Humanos , Idoso , Depressão/psicologia , Transtorno Depressivo Maior/epidemiologia , Colecionismo/epidemiologia , Reprodutibilidade dos Testes , Comportamento Compulsivo , Transtorno de Acumulação/diagnósticoRESUMO
OBJECTIVES: Late-life depression (LLD) is common and frequently co-occurs with neurodegenerative diseases of aging. Little is known about how heterogeneity within LLD relates to factors typically associated with neurodegeneration. Varying levels of anxiety are one source of heterogeneity in LLD. We examined associations between anxiety symptom severity and factors associated with neurodegeneration, including regional brain volumes, amyloid beta (Aß) deposition, white matter disease, cognitive dysfunction, and functional ability in LLD. PARTICIPANTS AND MEASUREMENTS: Older adults with major depression (N = 121, Ages 65-91) were evaluated for anxiety severity and the following: brain volume (orbitofrontal cortex [OFC], insula), cortical Aß standardized uptake value ratio (SUVR), white matter hyperintensity (WMH) volume, global cognition, and functional ability. Separate linear regression analyses adjusting for age, sex, and concurrent depression severity were conducted to examine associations between anxiety and each of these factors. A global regression analysis was then conducted to examine the relative associations of these variables with anxiety severity. RESULTS: Greater anxiety severity was associated with lower OFC volume (ß = -68.25, t = -2.18, p = .031) and greater cognitive dysfunction (ß = 0.23, t = 2.46, p = .016). Anxiety severity was not associated with insula volume, Aß SUVR, WMH, or functional ability. When examining the relative associations of cognitive functioning and OFC volume with anxiety in a global model, cognitive dysfunction (ß = 0.24, t = 2.62, p = .010), but not OFC volume, remained significantly associated with anxiety. CONCLUSIONS: Among multiple factors typically associated with neurodegeneration, cognitive dysfunction stands out as a key factor associated with anxiety severity in LLD which has implications for cognitive and psychiatric interventions.
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The following cases demonstrate a proof of concept for the safe and effective use of the glucagon-like-peptide-1 receptor agonist (GLP-1 RA) semaglutide for weight loss in obese, non-diabetic, end stage kidney disease (ESKD) patients on haemodialysis (HD), who are unable to undergo renal transplantation due to obesity. Obesity is a common barrier to wait-listing for renal transplantation with effective, broadly applicable weight loss strategies lacking. GLP-1 RAs have been shown to be effective adjuncts to achieve weight loss in non-diabetic obese people. However, the major clinical trials excluded patients with ESKD on dialysis. This paper outlines the successful use of semaglutide to achieve a target body mass index (BMI) prior to renal transplant wait-listing in two obese, non-diabetic, HD patients. These patients achieved a 16% and 12.6% weight loss in under 9 months with one now waitlisted and the other transplanted. This strategy has the potential for broader use in this patient cohort to improve wait-list times by overcoming this common barrier to renal transplantation.
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Índice de Massa Corporal , Peptídeos Semelhantes ao Glucagon , Falência Renal Crônica , Transplante de Rim , Obesidade , Listas de Espera , Redução de Peso , Humanos , Transplante de Rim/efeitos adversos , Falência Renal Crônica/terapia , Falência Renal Crônica/cirurgia , Falência Renal Crônica/complicações , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Peptídeos Semelhantes ao Glucagon/efeitos adversos , Obesidade/complicações , Redução de Peso/efeitos dos fármacos , Pessoa de Meia-Idade , Resultado do Tratamento , Masculino , Feminino , Diálise Renal , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Fatores de TempoRESUMO
BACKGROUND: Chronic kidney disease affects more than 10% of the world's population and is a non-communicable disease of global concern and priority. There is a significant implementation gap between best practice guideline recommendations and current kidney disease management. Previous research has shown the need to partner with primary care to improve education, collaboration, and kidney disease awareness. This implementation trial will explore use of an innovative clinical decision support software, Future Health Today, to improve screening, diagnosis, and management of kidney disease in primary care. The program will be supported by tertiary care outreach services. The primary aim is to test the hypothesis that the Future Health Today implementation program will improve screening, diagnosis, and management of kidney disease. Secondary aims are to evaluate primary care satisfaction and broader health service impacts. METHODS: This pre-post implementation trial using an interrupted time series design will evaluate the clinical and service outcomes of Future Health Today, using a mixed methods study in twenty general practices with an estimated population size of 150,000. Deidentified patient data will be extracted from participating practices to examine the primary aims of the study. Surveys and semi-structured interviews with general practice will inform secondary hypotheses. Data linkage between primary care and tertiary care data will examine the broader health service impacts. DISCUSSION: This investigator driven trial will assess the impact of Future Health Today software coupled with education and clinical outreach support. Investigators hypothesise that there will be improvement in appropriate screening, diagnosis, and management of kidney disease. This program has the potential to be scaled more broadly. TRIAL REGISTRATION: Australian New Zealand Clinical Trial Registry: ACTRN12623001096640.
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Sistemas de Apoio a Decisões Clínicas , Medicina Geral , Nefropatias , Humanos , Austrália , Análise de Séries Temporais Interrompida , Ensaios Clínicos como AssuntoRESUMO
BACKGROUND: Acute decompensated heart failure involves a high rate of mortality and complications. Management typically involves a multi-day hospital admission. However, patients often lose part of their function with each successive admission, and are at a high risk for hospital-associated complications such as nosocomial infection. This study aims to determine the safety and efficacy of the management of patients presenting with acute decompensated heart failure to clinic-based therapy vs usual inpatient care using a reproducible management pathway. METHOD: An investigator-initiated, prospective, non-inferiority, 1:1 randomised-controlled trial, stratified by left ventricular ejection fraction including 460 patients with a minimum follow-up of 7 days. This is a multi-centre study to be performed in centres across Victoria, Australia. Participants will be patients with either heart failure with reduced ejection fraction (HFrEF) or heart failure with preserved ejection fraction (HFpEF), admitted for acute decompensation of heart failure. INTERVENTION: Early discharge to an outpatient-based Heart Failure Rapid Access Clinical Review (RACER) in addition to frequent medical/nursing at-home review for patients admitted with decompensated heart failure. RESULTS: The primary endpoint will be a non-inferiority assessment of re-hospitalisation at 30 days. Secondary outcomes include superiority assessment of hospitalisation at 30 days, a composite clinical endpoint of major adverse cardiac and cerebrovascular event (MACCE), hospital re-admission or mortality at 3 months, achievement of guideline-directed medical therapy, patient assessment of symptoms (visual-analogue scale quantified as area under curve and Kansas City Cardiomyopathy Questionnaire-12 [KCCQ-12]), attendance at 3-month outpatient follow-up, number of bed stays/clinics attended, proportion of patients free from congestion, change in serum creatinine level, treatment for electrolyte disturbances, time to transition from intravenous to oral diuretics, and health economics analysis (cost-benefit analysis, cost-utility analysis, incremental cost-effectiveness ratio). CONCLUSIONS: The Early Discharge to Clinic-Based Therapy of Patients Presenting with Decompensated Heart Failure (EDICT-HF) trial will help determine whether earlier discharge to out-of-hospital care is non-inferior to the usual practice of inpatient care, in patients with heart failure admitted to hospital for acute decompensation, as an alternative model of care.
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Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/tratamento farmacológico , Alta do Paciente , Volume Sistólico , Estudos Prospectivos , Função Ventricular Esquerda , Vitória/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como AssuntoRESUMO
Marine herbivorous fish that feed primarily on macroalgae, such as those from the genus Kyphosus, are essential for maintaining coral health and abundance on tropical reefs. Here, deep metagenomic sequencing and assembly of gut compartment-specific samples from three sympatric, macroalgivorous Hawaiian kyphosid species have been used to connect host gut microbial taxa with predicted protein functional capacities likely to contribute to efficient macroalgal digestion. Bacterial community compositions, algal dietary sources, and predicted enzyme functionalities were analyzed in parallel for 16 metagenomes spanning the mid- and hindgut digestive regions of wild-caught fishes. Gene colocalization patterns of expanded carbohydrate (CAZy) and sulfatase (SulfAtlas) digestive enzyme families on assembled contigs were used to identify likely polysaccharide utilization locus associations and to visualize potential cooperative networks of extracellularly exported proteins targeting complex sulfated polysaccharides. These insights into the gut microbiota of herbivorous marine fish and their functional capabilities improve our understanding of the enzymes and microorganisms involved in digesting complex macroalgal sulfated polysaccharides. IMPORTANCE This work connects specific uncultured bacterial taxa with distinct polysaccharide digestion capabilities lacking in their marine vertebrate hosts, providing fresh insights into poorly understood processes for deconstructing complex sulfated polysaccharides and potential evolutionary mechanisms for microbial acquisition of expanded macroalgal utilization gene functions. Several thousand new marine-specific candidate enzyme sequences for polysaccharide utilization have been identified. These data provide foundational resources for future investigations into suppression of coral reef macroalgal overgrowth, fish host physiology, the use of macroalgal feedstocks in terrestrial and aquaculture animal feeds, and the bioconversion of macroalgae biomass into value-added commercial fuel and chemical products.
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Microbiota , Alga Marinha , Animais , Polissacarídeos , Sulfatos , Recifes de Corais , Peixes , Bactérias/genéticaRESUMO
BACKGROUND: Although women with polycystic kidney disease (PKD) generally have healthy pregnancies and babies, pregnancy is associated with a greater risk of maternal complications and requires planning and management of their condition. Given these possible complications, routine communication about childbearing between women with PKD and their treating team is important. A question prompt list (QPL), a structured list of questions used by patients during consultations with healthcare providers, may be beneficial in assisting women with PKD to discuss their childbearing concerns with, and seek related information from, their treating team. The aims of this study were to co-design a QPL about pregnancy and childbearing for women with PKD, and evaluate its comprehensibility, salience, and acceptability. METHODS: An exploratory sequential mixed-methods study of women of reproductive age with PKD living in Australia, using an experience-based co-design approach with two phases. Women were recruited from a metropolitan public health service and via social media and invited to complete an anonymous online survey about the development of the PKD QPL (phase one) and participate in an online discussion group about its refinement (phase two). RESULTS: Sixteen women completed the development survey and seven participated in the evaluation discussion group. Participants reported that women with PKD would value and use a QPL to prompt discussions with and seek further information about pregnancy and childbearing from their healthcare providers. Women identified four main topics for the QPL: 'thinking about having a baby', 'pregnancy', 'my medications' and 'after my baby is born'. Within each section a series of questions was developed. Based on the findings, a QPL about pregnancy and childbearing for women with PKD was co-designed. CONCLUSIONS: Women with PKD often find it difficult to access information and have discussions with their health care providers about pregnancy and childbearing. The PKD QPL co-designed in this study was perceived to be an acceptable tool which will, from the perspectives of participants, assist women with PKD to access information more easily about pregnancy, childbearing and PKD; ask more targeted questions of their treating team; and make informed childbearing decisions.
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Comunicação , Relações Médico-Paciente , Gravidez , Humanos , Feminino , Pessoal de Saúde , Família , Inquéritos e Questionários , Participação do PacienteRESUMO
BACKGROUND: The World Health Organisation (WHO) recommends all dialysis patients undertake routine screening for latent tuberculosis infection (LTBI) in high income countries such as Australia. However, we employ a targeted screening approach in our Australian dialysis unit in line with local and some international guidelines. We analysed our practices to assess the validity of our approach. METHODS: A retrospective review of new dialysis patients during the period 2012-2018 was undertaken. Patient records were reviewed for basic demographic data, comorbidities, LTBI screening using Quantiferon Gold (QFG), and outcomes, including episodes of active TB, to June 2020. RESULTS: 472 patients were included. WHO high risk country of origin patients accounted for 22% (n = 103). 229 patients (48.5%) were screened using QFG. The single main indication for screening was transplantation waitlisting. 34 patients had a positive QFG result. Active tuberculosis developed in two patients during the observation period. Both occurred in the screened cohort, the cases having previously tested negative via QFG at 11 and 16 months, prior to the development of active tuberculosis. No patients in the unscreened cohort developed active tuberculosis during the observation period. WHO high risk country of origin was associated with positive QFG status, odds ratio 10.4 (95% CI 3.3-31.2). CONCLUSION: The data failed to show a benefit from widening of the screening program within our dialysis unit. However, a much larger sample size will be required to confidently assess the impact of the current approach on patient outcomes. Analysis of current screening practices and outcomes across all Australian dialysis services is warranted to assess the risks and benefits of widening the screening practices to include all dialysis patients as recommended by the WHO.
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Renda , Diálise Renal , Humanos , Austrália/epidemiologia , Programas de Rastreamento , Prontuários MédicosRESUMO
BACKGROUND: Optimal vascular access is critical to successful haemodialysis. Acute thrombosis of haemodialysis access often leads to unplanned hospital admissions and interventions to restore patency. Western Health is a large health service in Victoria, Australia. During the period February 2019 to January 2020, the rate of arteriovenous fistula (AVF) and arteriovenous graft (AVG) at Western Health satellite dialysis units was 0.33 episodes per 1000 patient-days, higher than the reported rate in the literature of 0.24 events per 1000 patient-days, and was associated with a cumulative total of 139 days of inpatient stay (2.2 per 1000 patient-days). METHODS: The above results prompted creation of an education and escalation pathway for threatened haemodialysis access, based upon clinical markers of vascular access stenosis or imminent thrombosis assessed by nursing staff in satellite haemodialysis centres. In the period February 2020 to January 2021, the education and escalation pathway was implemented. We assessed referrals via the pathway, rates of AVF/AVG thrombosis and associated hospital length of stay in the following 12-month period (February 2021 to January 2022). RESULTS: Following introduction of the pathway, rates of AVF/AVG thrombosis declined to 0.15 per 1000 patient-days (p = 0.02), associated with a decline in attributable cumulative inpatient stay to 55 days (0.69 per 1000 patient-days). CONCLUSIONS: Our program demonstrates that the majority of thrombosed vascular access can be predicted and potentially averted with vigilant and well-practiced routine clinical assessment by trained nursing staff. Our nursing-led education and escalation program successfully identified vascular access at risk of imminent thrombosis, reduced rates of acute thrombosis and associated healthcare costs. Despite these improvements, there are still disparities in outcomes for patients with thrombosed vascular access, with regards to length of stay and requirement for insertion of a temporary central venous catheter (CVC) for urgent dialysis whilst awaiting intervention, and these are areas for further investigation and improvement.
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Fístula Arteriovenosa , Cateteres Venosos Centrais , Humanos , Diálise Renal , Escolaridade , Constrição Patológica , Vitória/epidemiologiaRESUMO
In this article, we present a four-channel direct digital synthesis (DDS) design that operates with a common clock ranging from 500 MHz to 24 GHz and generates output frequencies up to 1.75 GHz. A key feature of this board is its custom field-programmable gate array (FPGA)-based synchronization method, which ensures alignment accuracy of 170 ps between the channels, enabling precise frequency and phase relationship settings. In addition, the DDS board incorporates a user-friendly web interface that allows for continuous control and monitoring capabilities over TCP/IP. Multiple synchronized channels can be power-combined to produce a low-phase noise output due to coherent addition of the common carriers and the noncoherent addition of the residual DDS noise. By exploiting these principles and combining eight parallel channels of two DDS boards, we achieve exceptional residual phase noise performance, with L(1Hz)=-147dBc/Hz and L(100kHz)=-180dBc/Hz for a 9.765625 MHz output signal. These noise levels surpass the previously reported results achieved with regenerative frequency dividers. We also present a method for obtaining accurate residual noise measurements using an absolute phase modulation (PM) noise and amplitude modulation (AM) noise nalyse. Furthermore, we nalyse the phase alignment tolerances required to minimize the AM-to-PM and PM-to-AM conversion that commonly occurs in power-combined signals. Finally, we demonstrate the synthesis of a highly stable 9.765625 MHz signal obtained from a cavity-stabilized optical frequency comb (OFC), with an absolute white phase noise of -180 dBc/Hz.
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Coral reefs are highly productive ecosystems with distinct biogeochemistry and biology nestled within unproductive oligotrophic gyres. Coral reef islands have often been associated with a nearshore enhancement in phytoplankton, a phenomenon known as the Island Mass Effect (IME). Despite being documented more than 60 years ago, much remains unknown about the extent and drivers of IMEs. Here we utilized 16S rRNA gene metabarcoding as a biological tracer to elucidate horizontal and vertical influence of an IME around the islands of Mo'orea and Tahiti, French Polynesia. We show that those nearshore oceanic stations with elevated chlorophyll a included bacterioplankton found in high abundance in the reef environment, suggesting advection of reef water is the source of altered nearshore biogeochemistry. We also observed communities in the nearshore deep chlorophyll maximum (DCM) with enhanced abundances of upper euphotic bacterioplankton that correlated with intrusions of low-density, O2 rich water, suggesting island influence extends into the DCM.
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Antozoários , Ecossistema , Animais , Clorofila A , Recifes de Corais , RNA Ribossômico 16S/genética , ÁguaRESUMO
Reef-building corals form nutritional symbioses with endosymbiotic dinoflagellates (Symbiodiniaceae), a relationship that facilitates the ecological success of coral reefs. These symbionts are mostly acquired anew each generation from the environment during early life stages ("horizontal transmission"). Symbiodiniaceae species exhibit trait variation that directly impacts the health and performance of the coral host under ocean warming. Here, we test the capacity for larvae of a horizontally transmitting coral, Acropora tenuis, to establish symbioses with Symbiodiniaceae species in four genera that have varying thermal thresholds (the common symbiont genera, Cladocopium and Durusdinium, and the less common Fugacium and Gerakladium). Over a 2-week period in January 2018, a series of both no-choice and four-way choice experiments were conducted at three temperatures (27, 30, and 31°C). Symbiont acquisition success and cell proliferation were measured in individual larvae. Larvae successfully acquired and maintained symbionts of all four genera in no-choice experiments, and >80% of larvae were infected with at least three genera when offered a four-way choice. Unexpectedly, Gerakladium symbionts increased in dominance over time, and at high temperatures outcompeted Durusdinium, which is regarded as thermally tolerant. Although Fugacium displayed the highest thermal tolerance in culture and reached similar cell densities to the other three symbionts at 31°C, it remained a background symbiont in choice experiments, suggesting host preference for other symbiont species. Larval survivorship at 1 week was highest in larvae associated with Gerakladium and Fugacium symbionts at 27 and 30°C, however at 31°C, mortality was similar for all treatments. We hypothesize that symbionts that are currently rare in corals (e.g., Gerakladium) may become more common and widespread in early life stages under climate warming. Uptake of such symbionts may function as a survival strategy in the wild, and has implications for reef restoration practices that use sexually produced coral stock.
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Antozoários , Dinoflagellida , Animais , Recifes de Corais , Larva , Oceanos e Mares , Simbiose , TemperaturaRESUMO
Background: Enhancing community based Chronic Disease Management (CDM) will make significant impacts on all major chronic disease management outcome measures. There are no successful models of community hubs to triage and manage chronic diseases that significantly reduce readmissions, cost and improve chronic disease knowledge. Chronic heart failure (CHF) management foundations are built on guideline derived medical therapies (GDMT). These consensuses evidenced building blocks have to be interwoven into systems and processes of care which create access, collaboration and coordinate effective and innovative health services. Methods: Perspective and short communication. Conclusions: This review explores: (i) conventional chronic disease management in Australia; (ii) Possible options for future chronic diseases models of care that deliver key components of CHF management.
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Ocean warming is causing global coral bleaching events to increase in frequency, resulting in widespread coral mortality and disrupting the function of coral reef ecosystems. However, even during mass bleaching events, many corals resist bleaching despite exposure to abnormally high temperatures. While the physiological effects of bleaching have been well documented, the consequences of heat stress for bleaching-resistant individuals are not well understood. In addition, much remains to be learned about how heat stress affects cellular-level processes that may be overlooked at the organismal level, yet are crucial for coral performance in the short term and ecological success over the long term. Here we compared the physiological and cellular responses of bleaching-resistant and bleaching-susceptible corals throughout the 2019 marine heatwave in Hawai'i, a repeat bleaching event that occurred 4 years after the previous regional event. Relative bleaching susceptibility within species was consistent between the two bleaching events, yet corals of both resistant and susceptible phenotypes exhibited pronounced metabolic depression during the heatwave. At the cellular level, bleaching-susceptible corals had lower intracellular pH than bleaching-resistant corals at the peak of bleaching for both symbiont-hosting and symbiont-free cells, indicating greater disruption of acid-base homeostasis in bleaching-susceptible individuals. Notably, cells from both phenotypes were unable to compensate for experimentally induced cellular acidosis, indicating that acid-base regulation was significantly impaired at the cellular level even in bleaching-resistant corals and in cells containing symbionts. Thermal disturbances may thus have substantial ecological consequences, as even small reallocations in energy budgets to maintain homeostasis during stress can negatively affect fitness. These results suggest concern is warranted for corals coping with ocean acidification alongside ocean warming, as the feedback between temperature stress and acid-base regulation may further exacerbate the physiological effects of climate change.
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Antozoários , Animais , Recifes de Corais , Ecossistema , Havaí , Homeostase , Concentração de Íons de Hidrogênio , Água do Mar , SimbioseRESUMO
BACKGROUND: A new class of dialysis membrane, the mid cut-off (MCO) dialyzer, has been developed to improve the clearance of uremic toxins in hemodialysis (HD). The a tRial Evaluating Mid cut-Off Value membrane clearance of Albumin and Light chains in HemoDialysis patients (REMOVAL-HD) study aimed to determine if regular use of MCO dialyzer was safe and specifically did not result in a significant loss of albumin. METHODS: This investigator initiated, crossover, longitudinal, device study was conducted across 9 centers in Australia and New Zealand (n = 89). Participants had a 4-week wash-in with high-flux HD, followed by 24-week intervention with MCO HD and a subsequent 4-week wash-out with high-flux HD. The primary outcome was change in serum albumin between weeks 4 and 28. Secondary outcomes included trends in serum albumin, changes in kappa- and lambda-free light chains (FLC), 6-min walk test (6MWT), malnutrition inflammation score (MIS), restless legs score and quality of life. RESULTS: Participants had a mean age of 66 ± 14 years, 62% were men, 45% were anuric, and 51% had -diabetes. There was no reduction in serum albumin following treatment with MCO HD (mean reduction -0.7 g/L, 95% CI -1.5 to 0.1). A sustained, unexplained reduction in serum albumin (>25%) was not observed in any participant. A reduction in FLC was observed 2 weeks into MCO HD (lambda-FLC: Δ -9.1 mg/L, 95% CI -14.4 to -3.7; kappa-FLC: Δ -5.7 mg/L, 95% CI -9.8 to -1.6) and was sustained for the rest of the study intervention. Both FLC increased after the cessation of MCO use. There was no improvement in restless legs symptoms, quality of life, 6MWT or MIS scores. CONCLUSIONS: Regular HD using the MCO dialyzer did not result in a significant fall in serum albumin. There were no effects on quality of life, functional status or nutrition. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Number (ANZCTRN) 12616000804482.
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Cadeias kappa de Imunoglobulina/sangue , Cadeias lambda de Imunoglobulina/sangue , Membranas Artificiais , Diálise Renal/instrumentação , Albumina Sérica Humana/análise , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Diálise Renal/efeitos adversosRESUMO
Objectives: To assess the relationships of somatic and anxiety symptoms of depression with functional disability in a sample of older adults with late life depression.Method: Data were analyzed from 78 older adults aged 65-88 with current major depression. Somatic and anxiety symptoms from the 24-item Hamilton Depression Rating Scale (HDRS) were summed to create variables measuring severity of these symptoms. Other symptoms of depression were also assessed using the remaining items of the HDRS. Current physical health burden was assessed using the Functional Comorbidity Index (FCI). Disability was measured with the Late Life Function and Disability Instrument (LLFDI) total limitation score. A linear regression analysis was performed to assess the association of somatic and anxiety symptoms with disability independent of other factors.Results: The model accounted for 26.6% of variance in disability, (F(6,51) = 3.1, p = .01). Somatic (B = -1.9, p = .004) and anxiety (B = -3.7, p = .04) symptoms of depression were significantly associated with disability. Other depressive symptoms and physical illness burden were not associated with disability.Discussion: In older adults with major depression, somatic and anxiety symptoms of depression are associated with disability. Identification and treatment to remission of these symptoms may improve functional outcomes among older depressed adults.