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BACKGROUND: High triglyceride levels are associated with increased cardiovascular risk, but whether reductions in these levels would lower the incidence of cardiovascular events is uncertain. Pemafibrate, a selective peroxisome proliferator-activated receptor α modulator, reduces triglyceride levels and improves other lipid levels. METHODS: In a multinational, double-blind, randomized, controlled trial, we assigned patients with type 2 diabetes, mild-to-moderate hypertriglyceridemia (triglyceride level, 200 to 499 mg per deciliter), and high-density lipoprotein (HDL) cholesterol levels of 40 mg per deciliter or lower to receive pemafibrate (0.2-mg tablets twice daily) or matching placebo. Eligible patients were receiving guideline-directed lipid-lowering therapy or could not receive statin therapy without adverse effects and had low-density lipoprotein (LDL) cholesterol levels of 100 mg per deciliter or lower. The primary efficacy end point was a composite of nonfatal myocardial infarction, ischemic stroke, coronary revascularization, or death from cardiovascular causes. RESULTS: Among 10,497 patients (66.9% with previous cardiovascular disease), the median baseline fasting triglyceride level was 271 mg per deciliter, HDL cholesterol level 33 mg per deciliter, and LDL cholesterol level 78 mg per deciliter. The median follow-up was 3.4 years. As compared with placebo, the effects of pemafibrate on lipid levels at 4 months were -26.2% for triglycerides, -25.8% for very-low-density lipoprotein (VLDL) cholesterol, -25.6% for remnant cholesterol (cholesterol transported in triglyceride-rich lipoproteins after lipolysis and lipoprotein remodeling), -27.6% for apolipoprotein C-III, and 4.8% for apolipoprotein B. A primary end-point event occurred in 572 patients in the pemafibrate group and in 560 of those in the placebo group (hazard ratio, 1.03; 95% confidence interval, 0.91 to 1.15), with no apparent effect modification in any prespecified subgroup. The overall incidence of serious adverse events did not differ significantly between the groups, but pemafibrate was associated with a higher incidence of adverse renal events and venous thromboembolism and a lower incidence of nonalcoholic fatty liver disease. CONCLUSIONS: Among patients with type 2 diabetes, mild-to-moderate hypertriglyceridemia, and low HDL and LDL cholesterol levels, the incidence of cardiovascular events was not lower among those who received pemafibrate than among those who received placebo, although pemafibrate lowered triglyceride, VLDL cholesterol, remnant cholesterol, and apolipoprotein C-III levels. (Funded by the Kowa Research Institute; PROMINENT ClinicalTrials.gov number, NCT03071692.).
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Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Hipertrigliceridemia , Hipolipemiantes , PPAR alfa , Humanos , Apolipoproteína C-III/sangre , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Colesterol/sangre , LDL-Colesterol/sangre , Diabetes Mellitus Tipo 2/complicaciones , Método Doble Ciego , Factores de Riesgo de Enfermedad Cardiaca , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hiperlipidemias/sangre , Hiperlipidemias/tratamiento farmacológico , Hipertrigliceridemia/sangre , Hipertrigliceridemia/complicaciones , Hipertrigliceridemia/tratamiento farmacológico , Factores de Riesgo , Triglicéridos/sangre , Hipolipemiantes/uso terapéutico , PPAR alfa/agonistas , HDL-Colesterol/sangreRESUMEN
BACKGROUND: Altered kinase localization is gaining appreciation as a mechanism of cardiovascular disease. Previous work suggests GSK-3ß (glycogen synthase kinase 3ß) localizes to and regulates contractile function of the myofilament. We aimed to discover GSK-3ß's in vivo role in regulating myofilament function, the mechanisms involved, and the translational relevance. METHODS: Inducible cardiomyocyte-specific GSK-3ß knockout mice and left ventricular myocardium from nonfailing and failing human hearts were studied. RESULTS: Skinned cardiomyocytes from knockout mice failed to exhibit calcium sensitization with stretch indicating a loss of length-dependent activation (LDA), the mechanism underlying the Frank-Starling Law. Titin acts as a length sensor for LDA, and knockout mice had decreased titin stiffness compared with control mice, explaining the lack of LDA. Knockout mice exhibited no changes in titin isoforms, titin phosphorylation, or other thin filament phosphorylation sites known to affect passive tension or LDA. Mass spectrometry identified several z-disc proteins as myofilament phospho-substrates of GSK-3ß. Agreeing with the localization of its targets, GSK-3ß that is phosphorylated at Y216 binds to the z-disc. We showed pY216 was necessary and sufficient for z-disc binding using adenoviruses for wild-type, Y216F, and Y216E GSK-3ß in neonatal rat ventricular cardiomyocytes. One of GSK-3ß's z-disc targets, abLIM-1 (actin-binding LIM protein 1), binds to the z-disc domains of titin that are important for maintaining passive tension. Genetic knockdown of abLIM-1 via siRNA in human engineered heart tissues resulted in enhancement of LDA, indicating abLIM-1 may act as a negative regulator that is modulated by GSK-3ß. Last, GSK-3ß myofilament localization was reduced in left ventricular myocardium from failing human hearts, which correlated with depressed LDA. CONCLUSIONS: We identified a novel mechanism by which GSK-3ß localizes to the myofilament to modulate LDA. Importantly, z-disc GSK-3ß levels were reduced in patients with heart failure, indicating z-disc localized GSK-3ß is a possible therapeutic target to restore the Frank-Starling mechanism in patients with heart failure.
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Insuficiencia Cardíaca , Miocitos Cardíacos , Animales , Conectina/genética , Conectina/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/metabolismo , Humanos , Ratones , Ratones Noqueados , Miocitos Cardíacos/metabolismo , Fosforilación , RatasRESUMEN
Existing recommended first-line antibiotic agents for MRSA pneumonia have several shortcomings. We reviewed 29 cases of community- and hospital-acquired MRSA pneumonia managed at our hospital. Lincosamide monotherapy was administered to 21/29 (72%) and was the predominant antibiotic regimen (> 50% course duration) in 19/29 (66%). Patients receiving lincosamide-predominant monotherapy were no more likely to die or require intensive care unit admission than patients receiving vancomycin-predominant monotherapy (5/19 (26%) versus 4/7 (57%), p = 0.19); 5/7 (71%) patients admitted to ICU and 4/5 (80%) bacteraemic patients received lincosamide-predominant monotherapy. MRSA pneumonia can be safely treated with lincosamide monotherapy if the isolate is susceptible.
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Antibacterianos , Lincosamidas , Staphylococcus aureus Resistente a Meticilina , Neumonía Estafilocócica , Humanos , Antibacterianos/uso terapéutico , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Masculino , Femenino , Persona de Mediana Edad , Adulto , Neumonía Estafilocócica/tratamiento farmacológico , Neumonía Estafilocócica/microbiología , Anciano , Australia/epidemiología , Lincosamidas/uso terapéutico , Lincosamidas/farmacología , Resultado del Tratamiento , Estudios Retrospectivos , Adulto Joven , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/microbiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , Anciano de 80 o más AñosRESUMEN
BACKGROUND: In UKCTOCS, there was a decrease in the diagnosis of advanced stage tubo-ovarian cancer but no reduction in deaths in the multimodal screening group compared with the no screening group. Therefore, we did exploratory analyses of patients with high-grade serous ovarian cancer to understand the reason for the discrepancy. METHODS: UKCTOCS was a 13-centre randomised controlled trial of screening postmenopausal women from the general population, aged 50-74 years, with intact ovaries. The trial management system randomly allocated (2:1:1) eligible participants (recruited from April 17, 2001, to Sept 29, 2005) in blocks of 32 using computer generated random numbers to no screening or annual screening (multimodal screening or ultrasound screening) until Dec 31, 2011. Follow-up was through national registries until June 30, 2020. An outcome review committee, masked to randomisation group, adjudicated on ovarian cancer diagnosis, histotype, stage, and cause of death. In this study, analyses were intention-to-screen comparisons of women with high-grade serous cancer at censorship (Dec 31, 2014) in multimodal screening versus no screening, using descriptive statistics for stage and treatment endpoints, and the Versatile test for survival from randomisation. This trial is registered with the ISRCTN Registry, 22488978, and ClinicalTrials.gov, NCT00058032. FINDINGS: 202â562 eligible women were recruited (50â625 multimodal screening; 50â623 ultrasound screening; 101â314 no screening). 259 (0·5%) of 50â625 participants in the multimodal screening group and 520 (0·5%) of 101â314 in the no screening group were diagnosed with high-grade serous cancer. In the multimodal screening group compared with the no screening group, fewer were diagnosed with advanced stage disease (195 [75%] of 259 vs 446 [86%] of 520; p=0·0003), more had primary surgery (158 [61%] vs 219 [42%]; p<0·0001), more had zero residual disease following debulking surgery (119 [46%] vs 157 [30%]; p<0·0001), and more received treatment including both surgery and chemotherapy (192 [74%] vs 331 [64%]; p=0·0032). There was no difference in the first-line combination chemotherapy rate (142 [55%] vs 293 [56%]; p=0·69). Median follow-up from randomisation of 779 women with high-grade serous cancer in the multimodal and no screening groups was 9·51 years (IQR 6·04-13·00). At censorship (June 30, 2020), survival from randomisation was longer in women with high-grade serous cancer in the multimodal screening group than in the no screening group with absolute difference in survival of 6·9% (95% CI 0·4-13·0; p=0·042) at 18 years (21% [95% CI 15·6-26·2] vs 14% [95% CI 10·5-17·4]). INTERPRETATION: To our knowledge, this is the first evidence that screening can detect high-grade serous cancer earlier and lead to improved short-term treatment outcomes compared with no screening. The potential survival benefit for women with high-grade serous cancer was small, most likely due to only modest gains in early detection and treatment improvement, and tumour biology. The cumulative results of the trial suggest that surrogate endpoints for disease-specific mortality should not currently be used in screening trials for ovarian cancer. FUNDING: National Institute for Health Research, Medical Research Council, Cancer Research UK, The Eve Appeal.
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Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/tratamiento farmacológico , Resultado del Tratamiento , Tamizaje Masivo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéuticoRESUMEN
Familial cardiomyopathy is a precursor of heart failure and sudden cardiac death. Over the past several decades, researchers have discovered numerous gene mutations primarily in sarcomeric and cytoskeletal proteins causing two different disease phenotypes: hypertrophic (HCM) and dilated (DCM) cardiomyopathies. However, molecular mechanisms linking genotype to phenotype remain unclear. Here, we employ a systems approach by integrating experimental findings from preclinical studies (e.g., murine data) into a cohesive signaling network to scrutinize genotype to phenotype mechanisms. We developed an HCM/DCM signaling network model utilizing a logic-based differential equations approach and evaluated model performance in predicting experimental data from four contexts (HCM, DCM, pressure overload, and volume overload). The model has an overall prediction accuracy of 83.8%, with higher accuracy in the HCM context (90%) than DCM (75%). Global sensitivity analysis identifies key signaling reactions, with calcium-mediated myofilament force development and calcium-calmodulin kinase signaling ranking the highest. A structural revision analysis indicates potential missing interactions that primarily control calcium regulatory proteins, increasing model prediction accuracy. Combination pharmacotherapy analysis suggests that downregulation of signaling components such as calcium, titin and its associated proteins, growth factor receptors, ERK1/2, and PI3K-AKT could inhibit myocyte growth in HCM. In experiments with patient-specific iPSC-derived cardiomyocytes (MLP-W4R;MYH7-R723C iPSC-CMs), combined inhibition of ERK1/2 and PI3K-AKT rescued the HCM phenotype, as predicted by the model. In DCM, PI3K-AKT-NFAT downregulation combined with upregulation of Ras/ERK1/2 or titin or Gq protein could ameliorate cardiomyocyte morphology. The model results suggest that HCM mutations that increase active force through elevated calcium sensitivity could increase ERK activity and decrease eccentricity through parallel growth factors, Gq-mediated, and titin pathways. Moreover, the model simulated the influence of existing medications on cardiac growth in HCM and DCM contexts. This HCM/DCM signaling model demonstrates utility in investigating genotype to phenotype mechanisms in familial cardiomyopathy.
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Cardiomiopatías , Cardiomiopatía Hipertrófica , Insuficiencia Cardíaca , Animales , Ratones , Conectina/genética , Conectina/metabolismo , Miocitos Cardíacos/metabolismo , Cardiomiopatía Hipertrófica/genética , Calcio/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Cardiomiopatías/metabolismo , Insuficiencia Cardíaca/metabolismoRESUMEN
BACKGROUND: Familial hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease and is typically caused by mutations in genes encoding sarcomeric proteins that regulate cardiac contractility. HCM manifestations include left ventricular hypertrophy and heart failure, arrythmias, and sudden cardiac death. How dysregulated sarcomeric force production is sensed and leads to pathological remodeling remains poorly understood in HCM, thereby inhibiting the efficient development of new therapeutics. METHODS: Our discovery was based on insights from a severe phenotype of an individual with HCM and a second genetic alteration in a sarcomeric mechanosensing protein. We derived cardiomyocytes from patient-specific induced pluripotent stem cells and developed robust engineered heart tissues by seeding induced pluripotent stem cell-derived cardiomyocytes into a laser-cut scaffold possessing native cardiac fiber alignment to study human cardiac mechanobiology at both the cellular and tissue levels. Coupled with computational modeling for muscle contraction and rescue of disease phenotype by gene editing and pharmacological interventions, we have identified a new mechanotransduction pathway in HCM, shown to be essential in modulating the phenotypic expression of HCM in 5 families bearing distinct sarcomeric mutations. RESULTS: Enhanced actomyosin crossbridge formation caused by sarcomeric mutations in cardiac myosin heavy chain (MYH7) led to increased force generation, which, when coupled with slower twitch relaxation, destabilized the MLP (muscle LIM protein) stretch-sensing complex at the Z-disc. Subsequent reduction in the sarcomeric muscle LIM protein level caused disinhibition of calcineurin-nuclear factor of activated T-cells signaling, which promoted cardiac hypertrophy. We demonstrate that the common muscle LIM protein-W4R variant is an important modifier, exacerbating the phenotypic expression of HCM, but alone may not be a disease-causing mutation. By mitigating enhanced actomyosin crossbridge formation through either genetic or pharmacological means, we alleviated stress at the Z-disc, preventing the development of hypertrophy associated with sarcomeric mutations. CONCLUSIONS: Our studies have uncovered a novel biomechanical mechanism through which dysregulated sarcomeric force production is sensed and leads to pathological signaling, remodeling, and hypertrophic responses. Together, these establish the foundation for developing innovative mechanism-based treatments for HCM that stabilize the Z-disc MLP-mechanosensory complex.
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Cardiomiopatía Hipertrófica Familiar , Cardiomiopatía Hipertrófica , Actomiosina/genética , Humanos , Proteínas con Dominio LIM , Mecanotransducción Celular , Proteínas Musculares , Mutación , Miocitos CardíacosRESUMEN
Pollinating insects are declining due to habitat loss and climate change, and cities with limited habitat and floral resources may be particularly vulnerable. The effects of urban landscapes on pollination networks remain poorly understood, and comparative studies of taxa with divergent niches are lacking. Here, for the first time, we simultaneously compare nocturnal moth and diurnal bee pollen-transport networks using DNA metabarcoding and ask how pollination networks are affected by increasing urbanisation. Bees and moths exhibited substantial divergence in the communities of plants they interact with. Increasing urbanisation had comparable negative effects on pollen-transport networks of both taxa, with significant declines in pollen species richness. We show that moths are an important, but overlooked, component of urban pollen-transport networks for wild flowering plants, horticultural crops, and trees. Our findings highlight the need to include both bee and non-bee taxa when assessing the status of critical plant-insect interactions in urbanised landscapes.
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Mariposas Nocturnas , Urbanización , Animales , Abejas , Flores , Polen , Ecosistema , Productos Agrícolas , Insectos , PolinizaciónRESUMEN
We seek to elucidate the precise nature of mechanical loading that precipitates conduction deficits in a concealed-phase model of arrhythmogenic cardiomyopathy (ACM). ACM is a progressive disorder often resulting from mutations in desmosomal proteins. Exercise has been shown to worsen disease progression and unmask arrhythmia vulnerability, yet the underlying pathomechanisms may depend on the type and intensity of exercise. Because exercise causes myriad changes to multiple inter-dependent hemodynamic parameters, it is difficult to isolate its effects to specific changes in mechanical load. Here, we use engineered heart tissues (EHTs) with iPSC-derived cardiomyocytes expressing R451G desmoplakin, an ACM-linked mutation, which results in a functionally null model of desmoplakin (DSP). We also use a novel bioreactor to independently perturb tissue strain at different time points during the cardiac cycle. We culture EHTs under three strain regimes: normal physiological shortening; increased diastolic stretch, simulating high preload; and isometric culture, simulating high afterload. DSPR451G EHTs that have been cultured isometrically undergo adaptation, with no change in action potential parameters, conduction velocity, or contractile function, a phenotype confirmed by global proteomic analysis. However, when DSPR451G EHTs are subjected to increased diastolic stretch, they exhibit concomitant reductions in conduction velocity and the expression of connexin-43. These effects are rescued by inhibition of both lysosome activity and ERK signaling. Our results indicate that the response of DSPR451G EHTs to mechanical stimuli depends on the strain and the timing of the applied stimulus, with increased diastolic stretch unmasking conduction deficits in a concealed-phase model of ACM.
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OBJECTIVE: UKCTOCS provides an opportunity to explore symptoms in preclinical invasive epithelial ovarian cancer (iEOC). We report on symptoms in women with pre-clinical (screen-detected) cancers (PC) compared to clinically diagnosed (CD) cancers. METHODS: In UKCTOCS, 202638 postmenopausal women, aged 50-74 were randomly allocated (April 17, 2001-September 29, 2005) 2:1:1 to no screening or annual screening till Dec 31,2011, using a multimodal or ultrasound strategy. Follow-up was through national registries. An outcomes committee adjudicated on OC diagnosis, histotype, stage. Eligible women were those diagnosed with iEOC at primary censorship (Dec 31, 2014). Symptom details were extracted from trial clinical-assessment forms and medical records. Descriptive statistics were used to compare symptoms in PC versus CD women with early (I/II) and advanced (III/IV/unable to stage) stage high-grade-serous (HGSC) cancer. ISRCTN-22488978; ClinicalTrials.gov-NCT00058032. RESULTS: 1133 (286PC; 847CD) women developed iEOC. Median age (years) at diagnosis was earlier in PC compared to CD (66.8PC, 68.7CD, p = 0.0001) group. In the PC group, 48% (112/234; 90%, 660/730CD) reported symptoms when questioned. Half PC (50%, 13/26PC; 36%, 29/80CD; p = 0.213) women with symptomatic HGSC had >1symptom, with abdominal symptoms most common, both in early (62%, 16/26, PC; 53% 42/80, CD; p = 0.421) and advanced (57%, 49/86, PC; 74%, 431/580, CD; p = 0.001) stages. In symptomatic early-stage HGSC, compared to CD, PC women reported more gastrointestinal (change in bowel habits and dyspepsia) (35%, 9/26PC; 9%, 7/80CD; p = 0.001) and systemic (mostly lethargy/tiredness) (27%, 7/26PC; 9%, 7/80CD; p = 0.017) symptoms. CONCLUSIONS: Our findings, add to the growing evidence, that we should reconsider what constitutes alert symptoms for early tubo-ovarian cancer. We need a more nuanced complex of key symptoms which is then evaluated and refined in a prospective trial.
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Detección Precoz del Cáncer , Neoplasias Ováricas , Femenino , Humanos , Carcinoma Epitelial de Ovario/diagnóstico , Estudios Prospectivos , Neoplasias Ováricas/diagnóstico , Reino Unido/epidemiologíaRESUMEN
Larval dispersal is an important component of marine reserve networks. Two conceptually different approaches to incorporate dispersal connectivity into spatial planning of these networks exist, and it is an open question as to when either is most appropriate. Candidate reserve sites can be selected individually based on local properties of connectivity or on a spatial dependency-based approach of selecting clusters of strongly connected habitat patches. The first acts on individual sites, whereas the second acts on linked pairs of sites. We used a combination of larval dispersal simulations representing different seascapes and case studies of biophysical larval dispersal models in the Coral Triangle region and the province of Southeast Sulawesi, Indonesia, to compare the performance of these 2 methods in the spatial planning software Marxan. We explored the reserve design performance implications of different dispersal distances and patterns based on the equilibrium settlement of larvae in protected and unprotected areas. We further assessed different assumptions about metapopulation contributions from unprotected areas, including the case of 100% depletion and more moderate scenarios. The spatial dependency method was suitable when dispersal was limited, a high proportion of the area of interest was substantially degraded, or the target amount of habitat protected was low. Conversely, when subpopulations were well connected, the 100% depletion was relaxed, or more habitat was protected, protecting individual sites with high scores in metrics of connectivity was a better strategy. Spatial dependency methods generally produced more spatially clustered solutions with more benefits inside than outside reserves compared with site-based methods. Therefore, spatial dependency methods potentially provide better results for ecological persistence objectives over enhancing fisheries objectives, and vice versa. Different spatial prioritization methods of using connectivity are appropriate for different contexts, depending on dispersal characteristics, unprotected area contributions, habitat protection targets, and specific management objectives. Comparación entre los métodos de priorización de la conservación espacial con sitio y la conectividad espacial basada en la dependencia.
La dispersión larval es un componente importante de las redes de reservas marinas. Existen dos estrategias conceptualmente distintas para incorporar la conectividad de la dispersión en la planeación espacial de estas redes y es una pregunta abierta cuándo alguna de las dos es la más apropiada. Los sitios candidatos a reserva pueden ser seleccionados individualmente con base en las propiedades locales de la conectividad o en la estrategia espacial basada en la dependencia que consiste en seleccionar grupos de fragmentos de hábitat con un vínculo fuerte. La primera estrategia actúa sobre sitios individuales, mientras que la segunda actúa sobre pares de sitios vinculados. Usamos una combinación de simulaciones de dispersión larval que representaban a diferentes paisajes marinos y estudios de caso de modelos biofísicos de dispersión larval en la región del Triángulo de Coral y en la provincia de Sulawesi Sudoriental, Indonesia, para comparar el desempeño de estos dos métodos en el software de planeación espacial Marxan. Exploramos las implicaciones del desempeño del diseño de la reserva de diferentes distancias y patrones de dispersión basados en el establecimiento del equilibrio de larvas en las áreas protegidas y sin protección. Además, analizamos las suposiciones sobre las contribuciones metapoblacionales de las áreas sin protección, incluyendo el caso de la reducción al 100% y escenarios más moderados. El método de la dependencia espacial fue adecuado cuando la dispersión estuvo limitada, una proporción elevada del área de interés estaba sustancialmente degradada o era baja la cantidad meta de hábitat protegido. Al contrario, cuando las subpoblaciones estaban bien conectadas, la reducción al 100% estuvo relajada, o si una mayor parte del hábitat estaba protegido, la protección de los sitios individuales con altos puntajes en las medidas de conectividad fue una mejor estrategia. Los métodos de dependencia espacial generalmente produjeron soluciones con una agrupación más espacial y con más beneficios dentro que fuera de las reservas en comparación con los métodos basados sitios. Por lo tanto, los métodos de dependencia espacial tienen el potencial de proporcionar mejores resultados para los objetivos de persistencia ecológica por encima de los objetivos de mejora de las pesquerías, y viceversa. Los diferentes métodos de priorización espacial que usan la conectividad son apropiados para contextos diferentes, dependiendo de las características de dispersión, las contribuciones del área sin protección, las metas de protección del hábitat y los objetivos específicos del manejo.
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Conservación de los Recursos Naturales , Peces , Animales , Conservación de los Recursos Naturales/métodos , Ecosistema , Explotaciones Pesqueras , LarvaRESUMEN
Larval dispersal connectivity is typically integrated into spatial conservation decisions at regional or national scales, but implementing agencies struggle with translating these methods to local scales. We used larval dispersal connectivity at regional (hundreds of kilometers) and local (tens of kilometers) scales to aid in design of networks of no-take reserves in Southeast Sulawesi, Indonesia. We used Marxan with Connectivity informed by biophysical larval dispersal models and remotely sensed coral reef habitat data to design marine reserve networks for 4 commercially important reef species across the region. We complemented regional spatial prioritization with decision trees that combined network-based connectivity metrics and habitat quality to design reserve boundaries locally. Decision trees were used in consensus-based workshops with stakeholders to qualitatively assess site desirability, and Marxan was used to identify areas for subsequent network expansion. Priority areas for protection and expected benefits differed among species, with little overlap in reserve network solutions. Because reef quality varied considerably across reefs, we suggest reef degradation must inform the interpretation of larval dispersal patterns and the conservation benefits achievable from protecting reefs. Our methods can be readily applied by conservation practitioners, in this region and elsewhere, to integrate connectivity data across multiple spatial scales.
Integración de la conectividad larval al proceso de toma de decisiones en la conservación marina en escalas espaciales Resumen Comúnmente se integra la conectividad de la dispersión larval a las decisiones de conservación espacial a escalas regionales o nacionales, pero las agencias de implementación luchan con la transferencia de estos métodos a las escalas locales. Usamos la conectividad de la dispersión larval a escalas regionales (cientos de kilómetros) y locales (decenas de kilómetros) para ayudar en el diseño de redes de reservas con protección total en Sulawesi Sudoriental, Indonesia. Usamos Marxan con la conectividad guiada por los modelos biofísicos de dispersión larval y detectamos a distancia los datos de hábitat de los arrecifes de coral para diseñar redes de reservas marinas para cuatro especies de importancia comercial en la región. Complementamos la priorización espacial regional con árboles de decisión que combinaron medidas de conectividad basadas en las redes y la calidad del hábitat para diseñar localmente los límites de la reserva. Usamos los árboles de decisión con los actores en talleres basados en el consenso para evaluar cualitativamente la conveniencia del sitio. También usamos Marxan para identificar áreas para la expansión subsecuente de la red. Las áreas prioritarias para la protección y los beneficios esperados difirieron entre especies, con un traslape reducido en las soluciones de la red de reservas. Ya que la calidad del arrecife varió considerablemente entre los arrecifes, sugerimos que la degradación de estos debe orientar la interpretación de los patrones de dispersión larval y los beneficios de conservación alcanzables con la protección de los arrecifes. Los practicantes de la conservación pueden aplicar nuestros métodos inmediatamente, en esta región o en cualquier otra, para integrar los datos de conectividad en varias escalas espaciales.
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Conservación de los Recursos Naturales , Ecosistema , Animales , Larva , Arrecifes de Coral , IndonesiaRESUMEN
Understanding the relative effectiveness and enabling conditions of different area-based management tools is essential for supporting efforts that achieve positive biodiversity outcomes as area-based conservation coverage increases to meet newly set international targets. We used data from a coastal social-ecological monitoring program in 6 Indo-Pacific countries to analyze whether social, ecological, and economic objectives and specific management rules (temporal closures, fishing gear-specific, species-specific restrictions) were associated with coral reef fish biomass above sustainable yield levels across different types of area-based management tools (i.e., comparing those designated as marine protected areas [MPAs] with other types of area-based management). All categories of objectives, multiple combinations of rules, and all types of area-based management had some sites that were able to sustain high levels of reef fish biomass-a key measure for coral reef functioning-compared with reference sites with no area-based management. Yet, the same management types also had sites with low biomass. As governments advance their commitments to the Kunming-Montreal Global Biodiversity Framework and the target to conserve 30% of the planet's land and oceans by 2030, we found that although different types of management can be effective, most of the managed areas in our study regions did not meet criteria for effectiveness. These findings underscore the importance of strong management and governance of managed areas and the need to measure the ecological impact of area-based management rather than counting areas because of their designation.
Efectos de las reglas y objetivos de manejo sobre los resultados de conservación marina Resumen Es esencial entender la efectividad relativa y las condiciones habilitantes de las diferentes herramientas de manejo basadas en el área para respaldar los esfuerzos que brindan resultados positivos para la biodiversidad conforme aumenta la cobertura de la conservación basada en el área para alcanzar los objetivos internacionales recién establecidos. Usamos los datos de un programa de monitoreo socioeconómico costero en seis países del Indo-Pacífico para analizar si los objetivos sociales, ecológicos y económicos y las reglas específicas de manejo (cierres temporales, restricciones de equipo de pesca, vedas de especies) se asociaban con la biomasa de los peces de arrecife de coral por encima de los niveles de producción sustentable en diferentes tipos de herramientas de manejo basadas en el área (es decir, comparar aquellas designadas como áreas marinas protegidas[AMP] con otros tipos de manejo basado en el área). Todas las categorías de objetivos, las múltiples combinaciones de reglas y todos los tipos de manejo basado en el área tuvieron algunos sitios capaces de mantener los niveles altos de biomasa de peces de arrecife-una medida importante para el funcionamiento de los arrecifes-en comparación con los sitios de referencia sin manejo basado en el área. Sin embargo, los mismos tipos de manejo también tuvieron sitios con baja biomasa. Conforme los gobiernos avanzan en sus compromisos con el Marco Global de Biodiversidad de Kunming-Montreal y hacia el objetivo de conservar el 30% del suelo y los océanos del planeta para el 2030, descubrimos que, aunque diferentes tipos de manejo pueden ser efectivos, la mayoría de las áreas manejadas en nuestras regiones de estudio no cumplieron con los criterios de efectividad. Este descubrimiento enfatiza la importancia de una gestión y un gobierno sólidos de las áreas manejadas y la necesidad de medir el impacto ecológico del manejo basado en el área en lugar de contar las áreas por su designación.
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Biodiversidad , Conservación de los Recursos Naturales , Animales , Arrecifes de Coral , Océanos y Mares , PecesRESUMEN
Diabetes doubles the risk of developing heart failure (HF). As the prevalence of diabetes grows, so will HF unless the mechanisms connecting these diseases can be identified. Methylglyoxal (MG) is a glycolysis by-product that forms irreversible modifications on lysine and arginine, called glycation. We previously found that myofilament MG glycation causes sarcomere contractile dysfunction and is increased in patients with diabetes and HF. The aim of this study was to discover the molecular mechanisms by which MG glycation of myofilament proteins cause sarcomere dysfunction and to identify therapeutic avenues to compensate. In humans with type 2 diabetes without HF, we found increased glycation of sarcomeric actin compared to non-diabetics and it correlated with decreased calcium sensitivity. Depressed calcium sensitivity is pathogenic for HF, therefore myofilament glycation represents a promising therapeutic target to inhibit the development of HF in diabetics. To identify possible therapeutic targets, we further defined the molecular actions of myofilament glycation. Skinned myocytes exposed to 100 µM MG exhibited decreased calcium sensitivity, maximal calcium-activated force, and crossbridge kinetics. Replicating MG's functional affects using a computer simulation of sarcomere function predicted simultaneous decreases in tropomyosin's blocked-to-closed rate transition and crossbridge duty cycle were consistent with all experimental findings. Stopped-flow experiments and ATPase activity confirmed MG decreased the blocked-to-closed transition rate. Currently, no therapeutics target tropomyosin, so as proof-of-principal, we used a n-terminal peptide of myosin-binding protein C, previously shown to alter tropomyosin's position on actin. C0C2 completely rescued MG-induced calcium desensitization, suggesting a possible treatment for diabetic HF.
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Diabetes Mellitus Tipo 2 , Tropomiosina , Citoesqueleto de Actina/metabolismo , Calcio/metabolismo , Simulación por Computador , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Miofibrillas/metabolismo , Tropomiosina/metabolismoRESUMEN
BACKGROUND: Ovarian cancer continues to have a poor prognosis with the majority of women diagnosed with advanced disease. Therefore, we undertook the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) to determine if population screening can reduce deaths due to the disease. We report on ovarian cancer mortality after long-term follow-up in UKCTOCS. METHODS: In this randomised controlled trial, postmenopausal women aged 50-74 years were recruited from 13 centres in National Health Service trusts in England, Wales, and Northern Ireland. Exclusion criteria were bilateral oophorectomy, previous ovarian or active non-ovarian malignancy, or increased familial ovarian cancer risk. The trial management system confirmed eligibility and randomly allocated participants in blocks of 32 using computer generated random numbers to annual multimodal screening (MMS), annual transvaginal ultrasound screening (USS), or no screening, in a 1:1:2 ratio. Follow-up was through national registries. The primary outcome was death due to ovarian or tubal cancer (WHO 2014 criteria) by June 30, 2020. Analyses were by intention to screen, comparing MMS and USS separately with no screening using the versatile test. Investigators and participants were aware of screening type, whereas the outcomes review committee were masked to randomisation group. This study is registered with ISRCTN, 22488978, and ClinicalTrials.gov, NCT00058032. FINDINGS: Between April 17, 2001, and Sept 29, 2005, of 1 243 282 women invited, 202 638 were recruited and randomly assigned, and 202 562 were included in the analysis: 50 625 (25·0%) in the MMS group, 50 623 (25·0%) in the USS group, and 101 314 (50·0%) in the no screening group. At a median follow-up of 16·3 years (IQR 15·1-17·3), 2055 women were diagnosed with tubal or ovarian cancer: 522 (1·0%) of 50 625 in the MMS group, 517 (1·0%) of 50 623 in the USS group, and 1016 (1·0%) of 101 314 in the no screening group. Compared with no screening, there was a 47·2% (95% CI 19·7 to 81·1) increase in stage I and 24·5% (-41·8 to -2·0) decrease in stage IV disease incidence in the MMS group. Overall the incidence of stage I or II disease was 39·2% (95% CI 16·1 to 66·9) higher in the MMS group than in the no screening group, whereas the incidence of stage III or IV disease was 10·2% (-21·3 to 2·4) lower. 1206 women died of the disease: 296 (0·6%) of 50 625 in the MMS group, 291 (0·6%) of 50 623 in the USS group, and 619 (0·6%) of 101 314 in the no screening group. No significant reduction in ovarian and tubal cancer deaths was observed in the MMS (p=0·58) or USS (p=0·36) groups compared with the no screening group. INTERPRETATION: The reduction in stage III or IV disease incidence in the MMS group was not sufficient to translate into lives saved, illustrating the importance of specifying cancer mortality as the primary outcome in screening trials. Given that screening did not significantly reduce ovarian and tubal cancer deaths, general population screening cannot be recommended. FUNDING: National Institute for Health Research, Cancer Research UK, and The Eve Appeal.
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Carcinoma Epitelial de Ovario , Detección Precoz del Cáncer , Neoplasias Ováricas , Anciano , Antígeno Ca-125/sangre , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/mortalidad , Sistema de Registros , Medicina Estatal , Ultrasonografía , Reino Unido/epidemiologíaRESUMEN
The practice of ovarian stimulation for IVF is undergoing a fundamental re-evaluation as recent data begin to successfully challenge the traditional paradigm that ovarian stimulation should be aimed at the retrieval of as many oocytes as possible, in the belief that this will increase pregnancy rates. An opposing view is that live birth rate should not be the only end-point in evaluating the success of IVF treatment and that equal emphasis should be placed on safety and affordability. The International Society for Mild Approaches in Assisted Reproduction (ISMAAR) committee has carried out an up-to-date literature search, with the evidence being graded according to the University of Oxford's Centre for Evidence-Based Medicine. The recommendations were formulated taking into account the quality of evidence on the efficacy, risk and cost of each intervention. ISMAAR recommends adopting a mild approach to ovarian stimulation in all clinical settings as an increasing body of evidence suggests that mild stimulation is as effective as conventional stimulation, while being safer and less expensive. Mild ovarian stimulation could replace conventional stimulation, thus making IVF safer and more accessible worldwide.
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Fertilización In Vitro , Inducción de la Ovulación , Embarazo , Femenino , Humanos , Índice de Embarazo , Tasa de Natalidad , ReproducciónRESUMEN
This study reviewed the literature about the diagnosis, antepartum surveillance, and time of delivery of fetuses suspected to be small for gestational age or growth restricted. Several guidelines have been issued by major professional organizations, including the International Society of Ultrasound in Obstetrics and Gynecology and the Society for Maternal-Fetal Medicine. The differences in recommendations, in particular about Doppler velocimetry of the ductus venosus and middle cerebral artery, have created confusion among clinicians, and this review has intended to clarify and highlight the available evidence that is pertinent to clinical management. A fetus who is small for gestational age is frequently defined as one with an estimated fetal weight of <10th percentile. This condition has been considered syndromic and has been frequently attributed to fetal growth restriction, a constitutionally small fetus, congenital infections, chromosomal abnormalities, or genetic conditions. Small for gestational age is not synonymous with fetal growth restriction, which is defined by deceleration of fetal growth determined by a change in fetal growth velocity. An abnormal umbilical artery Doppler pulsatility index reflects an increased impedance to flow in the umbilical circulation and is considered to be an indicator of placental disease. The combined finding of an estimated fetal weight of <10th percentile and abnormal umbilical artery Doppler velocimetry has been widely accepted as indicative of fetal growth restriction. Clinical studies have shown that the gestational age at diagnosis can be used to subclassify suspected fetal growth restriction into early and late, depending on whether the condition is diagnosed before or after 32 weeks of gestation. The early type is associated with umbilical artery Doppler abnormalities, whereas the late type is often associated with a low pulsatility index in the middle cerebral artery. A large randomized clinical trial indicated that in the context of early suspected fetal growth restriction, the combination of computerized cardiotocography and fetal ductus venosus Doppler improves outcomes, such that 95% of surviving infants have a normal neurodevelopmental outcome at 2 years of age. A low middle cerebral artery pulsatility index is associated with an adverse perinatal outcome in late fetal growth restriction; however, there is no evidence supporting its use to determine the time of delivery. Nonetheless, an abnormality in middle cerebral artery Doppler could be valuable to increase the surveillance of the fetus at risk. We propose that fetal size, growth rate, uteroplacental Doppler indices, cardiotocography, and maternal conditions (ie, hypertension) according to gestational age are important factors in optimizing the outcome of suspected fetal growth restriction.
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Retardo del Crecimiento Fetal , Peso Fetal , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Retardo del Crecimiento Fetal/terapia , Edad Gestacional , Humanos , Lactante , Placenta , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Ultrasonografía Doppler , Ultrasonografía Prenatal , Arterias Umbilicales/diagnóstico por imagenRESUMEN
Ongoing declines in the structure and function of the world's coral reefs require novel approaches to sustain these ecosystems and the millions of people who depend on them3. A presently unexplored approach that draws on theory and practice in human health and rural development is to systematically identify and learn from the 'outliers'places where ecosystems are substantially better ('bright spots') or worse ('dark spots') than expected, given the environmental conditions and socioeconomic drivers they are exposed to. Here we compile data from more than 2,500 reefs worldwide and develop a Bayesian hierarchical model to generate expectations of how standing stocks of reef fish biomass are related to 18 socioeconomic drivers and environmental conditions. We identify 15 bright spots and 35 dark spots among our global survey of coral reefs, defined as sites that have biomass levels more than two standard deviations from expectations. Importantly, bright spots are not simply comprised of remote areas with low fishing pressure; they include localities where human populations and use of ecosystem resources is high, potentially providing insights into how communities have successfully confronted strong drivers of change. Conversely, dark spots are not necessarily the sites with the lowest absolute biomass and even include some remote, uninhabited locations often considered near pristine6. We surveyed local experts about social, institutional, and environmental conditions at these sites to reveal that bright spots are characterized by strong sociocultural institutions such as customary taboos and marine tenure, high levels of local engagement in management, high dependence on marine resources, and beneficial environmental conditions such as deep-water refuges. Alternatively, dark spots are characterized by intensive capture and storage technology and a recent history of environmental shocks. Our results suggest that investments in strengthening fisheries governance, particularly aspects such as participation and property rights, could facilitate innovative conservation actions that help communities defy expectations of global reef degradation.
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Conservación de los Recursos Naturales/métodos , Arrecifes de Coral , Ecosistema , Geografía , Animales , Teorema de Bayes , Biomasa , Conservación de los Recursos Naturales/legislación & jurisprudencia , Explotaciones Pesqueras/legislación & jurisprudencia , Peces , Factores Socioeconómicos , Vida SilvestreRESUMEN
We have created a novel in-vitro platform to study reverse remodeling of engineered heart tissue (EHT) after mechanical unloading. EHTs were created by seeding decellularized porcine myocardial sections with a mixture of primary neonatal rat ventricular myocytes and cardiac fibroblasts. Each end of the ribbon-like constructs was fixed to a plastic clip, allowing the tissues to be statically stretched or slackened. Inelastic deformation was introduced by stretching tissues by 20% of their original length. EHTs were subsequently unloaded by returning tissues to their original, shorter length. Mechanical characterization of EHTs immediately after unloading and at subsequent time points confirmed the presence of a reverse-remodeling process, through which stress-free tissue length was increased after chronic stretch but gradually decreased back to its original value within 9 days. When a cardiac myosin inhibitor was applied to tissues after unloading, EHTs failed to completely recover their passive and active mechanical properties, suggesting a role for actomyosin contraction in reverse remodeling. Selectively inhibiting cardiomyocyte contraction or fibroblast activity after mechanical unloading showed that contractile activity of both cell types was required to achieve full remodeling. Similar tests with EHTs formed from human induced pluripotent stem cell-derived cardiomyocytes also showed reverse remodeling that was enhanced when treated with omecamtiv mecarbil, a myosin activator. These experiments suggest essential roles for active sarcomeric contraction and fibroblast activity in reverse remodeling of myocardium after mechanical unloading. Our findings provide a mechanistic rationale for designing potential therapies to encourage reverse remodeling in patient hearts.
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Insuficiencia Cardíaca/metabolismo , Miocitos Cardíacos/metabolismo , Miofibroblastos/metabolismo , Sarcómeros/metabolismo , Transducción de Señal/efectos de los fármacos , Ingeniería de Tejidos/métodos , Remodelación Ventricular/efectos de los fármacos , Actomiosina/metabolismo , Animales , Animales Recién Nacidos , Benzamidas/farmacología , Bencilaminas/farmacología , Miosinas Cardíacas/antagonistas & inhibidores , Miosinas Cardíacas/metabolismo , Línea Celular , Dioxoles/farmacología , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Contracción Miocárdica/efectos de los fármacos , Miocardio/metabolismo , Miofibroblastos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptor Tipo I de Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Porcinos , Andamios del Tejido , Uracilo/análogos & derivados , Uracilo/farmacología , Urea/análogos & derivados , Urea/farmacologíaRESUMEN
The cardiac thin filament is regulated in a Ca2+-dependent manner through conformational changes of troponin and tropomyosin (Tm). It has been generally understood that under conditions of low Ca2+ the inhibitory peptide domain (IP) of troponin I (TnI) binds to actin and holds Tm over the myosin binding sites on actin to prevent crossbridge formation. More recently, evidence that the C-terminal mobile domain (MD) of TnI also binds actin has made for a more complex scenario. This study uses a computational model to investigate the consequences of assuming that TnI regulates Tm movement via two actin-binding domains rather than one. First, a 16-state model of the cardiac thin filament regulatory unit was created with TnI-IP as the sole regulatory domain. Expansion of this to include TnI-MD formed a 24-state model. Comparison of these models showed that assumption of a second actin-binding site allows the individual domains to have a lower affinity for actin than would be required for IP acting alone. Indeed, setting actin affinities of the IP and MD to 25% of that assumed for the IP in the single-site model was sufficient to achieve precisely the same degree of Ca2+ regulation. We also tested the 24-state model's ability to represent steady-state experimental data in the case of disruption of either the IP or MD. We were able to capture qualitative changes in several properties that matched what was seen in the experimental data. Lastly, simulations were run to examine the effect of disruption of the IP or MD on twitch dynamics. Our results suggest that both domains are required to keep diastolic cross-bridge activity to a minimum and accelerate myofilament relaxation. Overall, our analyses support a paradigm in which two domains of TnI bind with moderate affinity to actin, working in tandem to complete Ca2+-dependent regulation of the thin filament.