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1.
Mar Pollut Bull ; 206: 116738, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39079474

RESUMEN

Sponge bioerosion is an important process on many carbonate reef ecosystems. Eutrophication has been linked with an increase in boring sponge abundance and biomass in coral reefs, yet the impacts on sponge bioerosion rates remain largely unexplored within oyster reef communities. The present study evaluated the impacts of nitrate and phosphate addition on the bioerosion of Cliona celata inhabiting carbonate substrates in the subtropical southeastern U.S. Using in situ and aquarium manipulations, sponge bioerosion rates were compared among control and nutrient addition treatments in three experiments. Overall, there were no differences in loss of calcium carbonate substrate among treatments in any of the experiments, though very high rates of bioerosion (up to 0.11 g CaCO3 day-1) were observed in the field experiments. Future research should consider the impacts of both inorganic and organic nutrient loading to fully understand the impacts of eutrophication on boring sponge ecology in subtropical oyster reefs.

2.
Proc Natl Acad Sci U S A ; 121(27): e2317316121, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38917013

RESUMEN

A dispersed cytoplasmic distribution of mitochondria is a hallmark of normal cellular organization. Here, we have utilized the expression of exogenous Trak2 in mouse oocytes and embryos to disrupt the dispersed distribution of mitochondria by driving them into a large cytoplasmic aggregate. Our findings reveal that aggregated mitochondria have minimal impact on asymmetric meiotic cell divisions of the oocyte. In contrast, aggregated mitochondria during the first mitotic division result in daughter cells with unequal sizes and increased micronuclei. Further, in two-cell embryos, microtubule-mediated centering properties of the mitochondrial aggregate prevent nuclear centration, distort nuclear shape, and inhibit DNA synthesis and the onset of embryonic transcription. These findings demonstrate the motor protein-mediated distribution of mitochondria throughout the cytoplasm is highly regulated and is an essential feature of cytoplasmic organization to ensure optimal cell function.


Asunto(s)
Blastocisto , Núcleo Celular , Mitocondrias , Oocitos , Animales , Mitocondrias/metabolismo , Blastocisto/metabolismo , Blastocisto/citología , Ratones , Núcleo Celular/metabolismo , Oocitos/metabolismo , Oocitos/citología , Femenino , Desarrollo Embrionario/fisiología , Microtúbulos/metabolismo , Mitosis , Meiosis/fisiología
3.
Oecologia ; 205(2): 423-435, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38898336

RESUMEN

Spatial variation in parasitic infection may have many physical and biological drivers. Uncovering these drivers may be especially important for parasites of ecosystem engineers because the engineers are foundational to their communities. Oysters are an important coastal ecosystem engineer that have declined drastically worldwide, in part due to enhanced cases of lethal oyster diseases, such as Dermo and MSX, caused by the protozoan parasites Perkinsus marinus and Haplosporidium nelsoni, respectively. Besides water quality and hydrodynamics, there is little information on how other variables influence the prevalence and intensity of these pathogens in oysters across a regional scale. To examine drivers of spatial variation in these oyster parasites-including host size, local reef properties, and landscape properties-we sampled 24 reefs systematically spread along the coast of Georgia, USA. Across sites, we found universally high prevalence of oysters with at least one of these parasites (91.02% ± 8.89, mean ± SD). Not only are high levels of parasite prevalence potentially problematic for a pivotal ecosystem engineer, but also low spatial variability may limit the explanatory power of variables across a regional scale. Our statistical models explained between 18 and 42% of the variation in spatial patterns of prevalence and intensity of these microparasites. Interestingly, landscape context was a positive predictor of P. marinus, but a negative predictor of H. nelsoni. Overall, our findings suggest that factors driving parasite prevalence and intensity operate across multiple spatial scales, and the same factor can both facilitate and hinder different parasites within the same host species.


Asunto(s)
Ecosistema , Animales , Georgia , Ostreidae/parasitología , Interacciones Huésped-Parásitos , Prevalencia , Haplosporidios
4.
Physiol Meas ; 45(5)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38772400

RESUMEN

Objective.Highly comparative time series analysis (HCTSA) is a novel approach involving massive feature extraction using publicly available code from many disciplines. The Prematurity-Related Ventilatory Control (Pre-Vent) observational multicenter prospective study collected bedside monitor data from>700extremely preterm infants to identify physiologic features that predict respiratory outcomes.Approach. We calculated a subset of 33 HCTSA features on>7 M 10 min windows of oxygen saturation (SPO2) and heart rate (HR) from the Pre-Vent cohort to quantify predictive performance. This subset included representatives previously identified using unsupervised clustering on>3500HCTSA algorithms. We hypothesized that the best HCTSA algorithms would compare favorably to optimal PreVent physiologic predictor IH90_DPE (duration per event of intermittent hypoxemia events below 90%).Main Results.The top HCTSA features were from a cluster of algorithms associated with the autocorrelation of SPO2 time series and identified low frequency patterns of desaturation as high risk. These features had comparable performance to and were highly correlated with IH90_DPE but perhaps measure the physiologic status of an infant in a more robust way that warrants further investigation. The top HR HCTSA features were symbolic transformation measures that had previously been identified as strong predictors of neonatal mortality. HR metrics were only important predictors at early days of life which was likely due to the larger proportion of infants whose outcome was death by any cause. A simple HCTSA model using 3 top features outperformed IH90_DPE at day of life 7 (.778 versus .729) but was essentially equivalent at day of life 28 (.849 versus .850).Significance. These results validated the utility of a representative HCTSA approach but also provides additional evidence supporting IH90_DPE as an optimal predictor of respiratory outcomes.


Asunto(s)
Frecuencia Cardíaca , Recien Nacido Extremadamente Prematuro , Saturación de Oxígeno , Humanos , Frecuencia Cardíaca/fisiología , Recién Nacido , Saturación de Oxígeno/fisiología , Recien Nacido Extremadamente Prematuro/fisiología , Factores de Tiempo , Algoritmos , Respiración , Femenino , Estudios Prospectivos
5.
Neurology ; 102(10): e209388, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38701403

RESUMEN

BACKGROUND AND OBJECTIVES: Whether patent foramen ovale (PFO) closure benefits older patients with PFO and cryptogenic stroke is unknown because randomized controlled trials (RCTs) have predominantly enrolled patients younger than 60 years of age. Our objective was to estimate anticipated effects of PFO closure in older patients to predict the numbers needed to plan an RCT. METHODS: Effectiveness estimates are derived from major observational studies (Risk of Paradoxical Embolism [RoPE] Study and Oxford Vascular Study, together referred to as the "RoPE-Ox" database) and all 6 major RCTs (Systematic, Collaborative, PFO Closure Evaluation [SCOPE] Consortium). To estimate stroke recurrence risk, observed outcomes were calculated for patients older than 60 years in the age-inclusive observational databases (n = 549). To estimate the reduction in the rate of recurrent stroke associated with PFO closure vs medical therapy based on the RoPE score and the presence of high-risk PFO features, a Cox proportional hazards regression model was developed on the RCT data in the SCOPE database (n = 3,740). These estimates were used to calculate sample sizes required for a future RCT. RESULTS: Five-year risk of stroke recurrence using Kaplan-Meier estimates was 13.7 (95% CI 10.5-17.9) overall, 14.9% (95% CI 10.2-21.6) in those with high-risk PFO features. Predicted relative reduction in the event rate with PFO closure was 12.9% overall, 48.8% in those with a high-risk PFO feature. Using these estimates, enrolling all older patients with cryptogenic stroke and PFO would require much larger samples than those used for prior PFO closure trials, but selectively enrolling patients with high-risk PFO features would require totals of 630 patients for 90% power and 471 patients for 80% power, with an average of 5 years of follow-up. DISCUSSION: Based on our projections, anticipated effect sizes in older patients with high-risk features make a trial in these subjects feasible. With lengthening life expectancy in almost all regions of the world, the utility of PFO closure in older adults is increasingly important to explore.


Asunto(s)
Estudios de Factibilidad , Foramen Oval Permeable , Selección de Paciente , Accidente Cerebrovascular , Humanos , Foramen Oval Permeable/complicaciones , Foramen Oval Permeable/cirugía , Anciano , Accidente Cerebrovascular/etiología , Masculino , Femenino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Resultado del Tratamiento , Factores de Edad , Anciano de 80 o más Años
6.
J Pediatr ; 271: 114042, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38570031

RESUMEN

OBJECTIVE: The objective of this study was to examine the association of cardiorespiratory events, including apnea, periodic breathing, intermittent hypoxemia (IH), and bradycardia, with late-onset sepsis for extremely preterm infants (<29 weeks of gestational age) on vs off invasive mechanical ventilation. STUDY DESIGN: This is a retrospective analysis of data from infants enrolled in Pre-Vent (ClinicalTrials.gov identifier NCT03174301), an observational study in 5 level IV neonatal intensive care units. Clinical data were analyzed for 737 infants (mean gestational age: 26.4 weeks, SD 1.71). Monitoring data were available and analyzed for 719 infants (47 512 patient-days); of whom, 109 had 123 sepsis events. Using continuous monitoring data, we quantified apnea, periodic breathing, bradycardia, and IH. We analyzed the relationships between these daily measures and late-onset sepsis (positive blood culture >72 hours after birth and ≥5-day antibiotics). RESULTS: For infants not on a ventilator, apnea, periodic breathing, and bradycardia increased before sepsis diagnosis. During times on a ventilator, increased sepsis risk was associated with longer events with oxygen saturation <80% (IH80) and more bradycardia events before sepsis. IH events were associated with higher sepsis risk but did not dynamically increase before sepsis, regardless of ventilator status. A multivariable model including postmenstrual age, cardiorespiratory variables (apnea, periodic breathing, IH80, and bradycardia), and ventilator status predicted sepsis with an area under the receiver operator characteristic curve of 0.783. CONCLUSION: We identified cardiorespiratory signatures of late-onset sepsis. Longer IH events were associated with increased sepsis risk but did not change temporally near diagnosis. Increases in bradycardia, apnea, and periodic breathing preceded the clinical diagnosis of sepsis.


Asunto(s)
Apnea , Bradicardia , Hipoxia , Recien Nacido Extremadamente Prematuro , Sepsis , Humanos , Bradicardia/epidemiología , Bradicardia/etiología , Apnea/epidemiología , Estudios Retrospectivos , Recién Nacido , Hipoxia/complicaciones , Femenino , Masculino , Sepsis/complicaciones , Sepsis/epidemiología , Enfermedades del Prematuro/epidemiología , Enfermedades del Prematuro/diagnóstico , Respiración Artificial , Unidades de Cuidado Intensivo Neonatal , Edad Gestacional
7.
Genes (Basel) ; 15(3)2024 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-38540426

RESUMEN

Mitochondria undergo a myriad of changes during pre-implantation embryo development, including shifts in activity levels and mitochondrial DNA (mtDNA) replication. However, how these distinct aspects of mitochondrial function are linked and their responsiveness to diverse stressors is not well understood. Here, we show that mtDNA content increased between 8-cell embryos and the blastocyst stage, with similar copy numbers per cell in the inner cell mass (ICM) and trophectoderm (TE). In contrast, mitochondrial membrane potential (MMP) was higher in TE than ICM. Culture in ambient oxygen (20% O2) altered both aspects of mitochondrial function: the mtDNA copy number was upregulated in ICM, while MMP was diminished in TE. Embryos cultured in 20% O2 also exhibited delayed development kinetics, impaired implantation, and reduced mtDNA levels in E18 fetal liver. A model of oocyte mitochondrial stress using rotenone showed only a modest effect on on-time development and did not alter the mtDNA copy number in ICM; however, following embryo transfer, mtDNA was higher in the fetal heart. Lastly, endogenous mitochondrial dysfunction, induced by maternal age and obesity, altered the blastocyst mtDNA copy number, but not within the ICM. These results demonstrate that mitochondrial activity and mtDNA content exhibit cell-specific changes and are differentially responsive to diverse types of oxidative stress during pre-implantation embryogenesis.


Asunto(s)
Variaciones en el Número de Copia de ADN , ADN Mitocondrial , Animales , Ratones , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Variaciones en el Número de Copia de ADN/genética , Potenciales de la Membrana , Mitocondrias/metabolismo , Estrés Oxidativo/genética , Desarrollo Embrionario/genética , Oxígeno/metabolismo
8.
medRxiv ; 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38343830

RESUMEN

Objective: Highly comparative time series analysis (HCTSA) is a novel approach involving massive feature extraction using publicly available code from many disciplines. The Prematurity-Related Ventilatory Control (Pre-Vent) observational multicenter prospective study collected bedside monitor data from > 700 extremely preterm infants to identify physiologic features that predict respiratory outcomes. We calculated a subset of 33 HCTSA features on > 7M 10-minute windows of oxygen saturation (SPO2) and heart rate (HR) from the Pre-Vent cohort to quantify predictive performance. This subset included representatives previously identified using unsupervised clustering on > 3500 HCTSA algorithms. Performance of each feature was measured by individual area under the receiver operating curve (AUC) at various days of life and binary respiratory outcomes. These were compared to optimal PreVent physiologic predictor IH90 DPE, the duration per event of intermittent hypoxemia events with threshold of 90%. Main Results: The top HCTSA features were from a cluster of algorithms associated with the autocorrelation of SPO2 time series and identified low frequency patterns of desaturation as high risk. These features had comparable performance to and were highly correlated with IH90_DPE but perhaps measure the physiologic status of an infant in a more robust way that warrants further investigation. The top HR HCTSA features were symbolic transformation measures that had previously been identified as strong predictors of neonatal mortality. HR metrics were only important predictors at early days of life which was likely due to the larger proportion of infants whose outcome was death by any cause. A simple HCTSA model using 3 top features outperformed IH90_DPE at day of life 7 (.778 versus .729) but was essentially equivalent at day of life 28 (.849 versus .850). These results validated the utility of a representative HCTSA approach but also provides additional evidence supporting IH90_DPE as an optimal predictor of respiratory outcomes.

9.
medRxiv ; 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38343825

RESUMEN

Objectives: Detection of changes in cardiorespiratory events, including apnea, periodic breathing, intermittent hypoxemia (IH), and bradycardia, may facilitate earlier detection of sepsis. Our objective was to examine the association of cardiorespiratory events with late-onset sepsis for extremely preterm infants (<29 weeks' gestational age (GA)) on versus off invasive mechanical ventilation. Study Design: Retrospective analysis of data from infants enrolled in Pre-Vent (ClinicalTrials.gov identifier NCT03174301), an observational study in five level IV neonatal intensive care units. Clinical data were analyzed for 737 infants (mean GA 26.4w, SD 1.71). Monitoring data were available and analyzed for 719 infants (47,512 patient-days), of whom 109 had 123 sepsis events. Using continuous monitoring data, we quantified apnea, periodic breathing, bradycardia, and IH. We analyzed the relationships between these daily measures and late-onset sepsis (positive blood culture >72h after birth and ≥5d antibiotics). Results: For infants not on a ventilator, apnea, periodic breathing, and bradycardia increased before sepsis diagnosis. During times on a ventilator, increased sepsis risk was associated with longer IH80 events and more bradycardia events before sepsis. IH events were associated with higher sepsis risk, but did not dynamically increase before sepsis, regardless of ventilator status. A multivariable model predicted sepsis with an AUC of 0.783. Conclusion: We identified cardiorespiratory signatures of late-onset sepsis. Longer IH events were associated with increased sepsis risk but did not change temporally near diagnosis. Increases in bradycardia, apnea, and periodic breathing preceded the clinical diagnosis of sepsis.

10.
JACC Cardiovasc Interv ; 17(4): 505-515, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38340102

RESUMEN

BACKGROUND: A single, multitiered valve center designation has been proposed to publicly identify centers with expertise for all valve therapies. The correlation between transcatheter aortic valve replacement (TAVR) and mitral transcatheter edge-to-edge repair (MTEER) procedures is unknown. OBJECTIVES: The authors sought to examine the relationship between site-level volumes and outcomes for TAVR and MTEER. We further explored variability between sites for MTEER outcomes. METHODS: Using the STS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) national registry, TAVR and MTEER procedures at sites offering both therapies from 2013 to 2022 were examined. Sites were ranked into deciles of adjusted in-hospital and 30-day outcomes separately for TAVR and MTEER and compared. Stepwise, hierarchical multivariable models were constructed for MTEER outcomes, and the median OR was calculated. RESULTS: Between 2013 and 2022, 384,394 TAVRs and 53,274 MTEERs (median annualized volumes: 93.6 and 18.8, respectively) were performed across 453 U.S. sites. Annualized TAVR and MTEER volumes were moderately correlated (r = 0.48; P < 0.001). After adjustment, 14.3% of sites had the same decile rank for TAVR and MTEER 30-day composite outcome, 50.6% were within 2 decile ranks; 35% had more discordant outcomes for the 2 procedures (P = 0.0005). For MTEER procedures, the median OR for the 30-day composite outcome was 1.57 (95% CI: 1.51-1.64), indicating a 57% variability in outcome by site. CONCLUSIONS: There is modest correlation between hospital-level volumes for TAVR and MTEER but low interprocedural correlation of outcomes. For similar patients, site-level variability for mortality/morbidity following MTEER was high. Factors influencing outcomes and "centers of excellence" as a whole may differ for TAVR and MTEER.


Asunto(s)
Estenosis de la Válvula Aórtica , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Estados Unidos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/etiología , Resultado del Tratamiento , Sistema de Registros , Hospitales , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Factores de Riesgo
12.
Pediatr Res ; 95(4): 1060-1069, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37857848

RESUMEN

BACKGROUND: In extremely preterm infants, persistence of cardioventilatory events is associated with long-term morbidity. Therefore, the objective was to characterize physiologic growth curves of apnea, periodic breathing, intermittent hypoxemia, and bradycardia in extremely preterm infants during the first few months of life. METHODS: The Prematurity-Related Ventilatory Control study included 717 preterm infants <29 weeks gestation. Waveforms were downloaded from bedside monitors with a novel sharing analytics strategy utilized to run software locally, with summary data sent to the Data Coordinating Center for compilation. RESULTS: Apnea, periodic breathing, and intermittent hypoxemia events rose from day 3 of life then fell to near-resolution by 8-12 weeks of age. Apnea/intermittent hypoxemia were inversely correlated with gestational age, peaking at 3-4 weeks of age. Periodic breathing was positively correlated with gestational age peaking at 31-33 weeks postmenstrual age. Females had more periodic breathing but less intermittent hypoxemia/bradycardia. White infants had more apnea/periodic breathing/intermittent hypoxemia. Infants never receiving mechanical ventilation followed similar postnatal trajectories but with less apnea and intermittent hypoxemia, and more periodic breathing. CONCLUSIONS: Cardioventilatory events peak during the first month of life but the actual postnatal trajectory is dependent on the type of event, race, sex and use of mechanical ventilation. IMPACT: Physiologic curves of cardiorespiratory events in extremely preterm-born infants offer (1) objective measures to assess individual patient courses and (2) guides for research into control of ventilation, biomarkers and outcomes. Presented are updated maturational trajectories of apnea, periodic breathing, intermittent hypoxemia, and bradycardia in 717 infants born <29 weeks gestation from the multi-site NHLBI-funded Pre-Vent study. Cardioventilatory events peak during the first month of life but the actual postnatal trajectory is dependent on the type of event, race, sex and use of mechanical ventilation. Different time courses for apnea and periodic breathing suggest different maturational mechanisms.


Asunto(s)
Enfermedades del Prematuro , Trastornos Respiratorios , Lactante , Femenino , Recién Nacido , Humanos , Recien Nacido Extremadamente Prematuro , Apnea , Bradicardia/terapia , Respiración , Hipoxia
14.
J Vasc Access ; : 11297298231210019, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37997016

RESUMEN

BACKGROUND: Arteriovenous fistulae (AVF) and Arteriovenous Grafts (AVG) may present a problematic vascular access for renal replacement therapy (RRT), reliant on recurrent specialist nurse and medical evaluation. Dysfunctional accesses are frequently referred 'out of the dialysis clinic' for specialist sonographic examination, with associated delays potentiating loss of vascular access viability and/or need for emergency intervention. Definitive anatomical and functional diagnostics based in the dialysis unit may help to solve these delays and associated complications. OBJECTIVES: This publication reports a novel vascular access monitoring concept, Robotic Tomographic Ultrasound (RTU). RESEARCH DESIGN: Robotic Tomographic Ultrasound incorporates a semi-autonomous, robotic vascular ultrasound system and purpose designed analysis software that can be deployed at the point of care. Three-dimensional scan data, as well as conventional B-Mode and Doppler data are obtained by the system and transferred to a cloud based reporting and analysis software. Scans are remotely annotated and interpreted by a sonographer, with diagnostic data presented securely to clinicians on their preferred web based application/web connected device. RESULTS: Software developed specifically for pre AVF mapping, maturation and monitoring protocols, analyse the data and then present interpreted results to all caring clinicians to assist with decision making. Vascular access planning can be determined with high confidence with data from the Map module. Maturation data can be presented in line with institutional requirements to the dialysis nurse, facilitating precocious needle access. CONCLUSION: Robotic Tomographic Ultrasound is a novel approach to vascular access management that may reduce the risk of loss of functional access by regular monitoring with the system; automated alerts guiding clinicians to the need for pre-emptive intervention, and the potential to increase longevity of the vascular access.

15.
Am J Trop Med Hyg ; 109(5): 1036-1046, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37748764

RESUMEN

Malaria remains the leading cause of acute febrile illness (AFI) in Africa despite successful control measures and programs. Acute febrile illnesses can be misdiagnosed as malaria as a result of the overlapping spectrum of nonspecific symptoms or may not be pursued because of limited diagnostic capabilities. This study investigated potential etiologies of AFIs in Ghana and determined the relationship between coinfection between malaria and Q fever, leptospirosis, and culturable bacteria in febrile patients. Participants were enrolled between July 2015 and December 2019 from four Ghanaian military treatment facilities. Of the 399 febrile participants, 222 (55.6%) males and 177 (44.6%) females were enrolled. Malaria was diagnosed in 275 (68.9%) participants. Malaria coinfection occurred with leptospirosis, Q fever, and blood-cultured bacteria in 11/206 (5.3%), 24/206 (11.7%), and 6/164 (3.7%) participants, respectively. Among the 124 malaria-negative samples, the positivity rates were 4.1% (3/74), 8.1% (6/74), and 3.6% (2/56) for leptospirosis, Q fever, and bacterial pathogens isolated from blood culture, respectively. The majority of documented clinical signs and symptoms were not significantly associated with specific diseases. Approximately 10% of malaria-positive participants also had evidence suggesting the presence of a bacterial coinfection. Therefore, even in the case of a positive malaria test, other pathogens contributing to febrile illness should be considered. Understanding the frequency of malaria coinfection and other etiological agents responsible for AFIs will improve diagnosis and treatment and better inform public health knowledge gaps in Ghana.


Asunto(s)
Coinfección , Leptospirosis , Malaria , Fiebre Q , Masculino , Femenino , Humanos , Coinfección/epidemiología , Coinfección/complicaciones , Ghana/epidemiología , Fiebre Q/complicaciones , Malaria/complicaciones , Malaria/epidemiología , Malaria/diagnóstico , Fiebre/etiología , Leptospirosis/complicaciones , Leptospirosis/epidemiología , Leptospirosis/diagnóstico , Bacterias
16.
PeerJ ; 11: e15837, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37554337

RESUMEN

Eastern oysters, Crassostrea virginica, are commercially important coastal species that provide many ecosystem services for coastal communities. Unfortunately, 85% of oyster reefs have been lost globally, prompting investments in restoration efforts to rebuild populations. Managers often consider several well-studied environmental and water quality parameters when making restoration site decisions. However, recent research suggests that submarine groundwater discharge (SGD) may play a role in driving the distribution of oysters in some estuaries. Specifically, SGD may result in localized areas of low dissolved oxygen and low pH that could inhibit oyster recruitment and survival. However, SGD may interact with other potential oyster stressors, including creek geomorphology. On point bars, sediment accumulation could alter growth rates of oysters and physiology, and it is possible that the two factors, SGD and creek geomorphology, could interact to impact oyster growth. We conducted a field experiment to examine the effects of SGD and creek geomorphology on oyster growth rates in a marsh-lined tidal creek in Georgia, USA. High and low SGD sites were paired within point bars and cut banks. Oysters were deployed in cages for 72 days and growth rates were determined. We found a significant interaction between SGD and creek geomorphology on oyster growth rates. Oysters grew at significantly faster rates at locations on accretionary point bars regardless of SGD flux, whereas, on erosional cut banks, high SGD flux significantly reduced oyster growth rate relative to low SGD flux. It appears that SGD may negatively influence oyster growth at specific creek locations, likely due to the presence of other stressors. Therefore, it is important to consider potential interacting and confounding stressors when managing oyster populations. As SGD is still a relatively understudied potential stressor for oysters, it is critical to continue to examine how groundwater might influence oysters in other locations and in combination with other stressors. Regardless, this study provides further evidence that SGD should be considered in future management efforts.


Asunto(s)
Crassostrea , Agua Subterránea , Animales , Ecosistema , Georgia , Humedales
17.
Microorganisms ; 11(7)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37512980

RESUMEN

Eastern oysters, Crassostrea virginica, are ecologically and economically important coastal species which provide a commercially valuable food product while also improving water quality through filtration, protecting shorelines, and providing habitat. The protozoan parasites Perkinsus marinus and Haplosporidium nesloni commonly infect oysters along the United States Atlantic and Gulf coasts and have been linked to poor oyster health and mass mortality events. In this study, wild oysters were collected from multiple reefs within four tidal creeks along the coast of Georgia to investigate P. marinus and H. nelsoni prevalence and intensity, their potential impact on oyster health, and identify possible drivers of the parasites. A second study occurred on four sites on Sapelo Island, Georgia, with continuous water quality monitoring data to further elucidate potential drivers. Oyster density and condition index, a proxy for health, were measured, and parasites were quantified using a TaqMan probe based quantitative real-time PCR within gill tissue. Real-time PCR showed that 86% of oysters tested were infected by one or both parasites in the coast-wide survey, and 93% of oysters from Sapelo Island were also infected by one or both parasites. Prevalence and infection intensity for both P. marinus and H. nelsoni varied across sites. Overall impacts on oysters were complex-intensity was not linked to oyster metrics in the coastwide study, but oyster condition was negatively correlated with P. marinus prevalence in the Sapelo Island study. Several relationships between both parasites and water quality parameters were identified, providing valuable information about potential drivers that should be investigated further.

18.
Cell Death Dis ; 14(7): 397, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37407587

RESUMEN

Mammalian oocytes spend most of their life in a unique state of cell cycle arrest at meiotic prophase I, during which time they are exposed to countless DNA-damaging events. Recent studies have shown that DNA double-strand break repair occurs predominantly via the homologous recombination (HR) pathway in small non-growing meiotically arrested oocytes (primordial follicle stage). However, the DNA repair mechanisms employed by fully grown meiotically arrested oocytes (GV-stage) have not been studied in detail. Here we established a conditional knockout mouse model to explore the role of Ku80, a critical component of the nonhomologous end joining (NHEJ) pathway, in the repair of DNA damage in GV oocytes. GV oocytes lacking Ku80 failed to repair etoposide-induced DNA damage, even when only low levels of damage were sustained. This indicates Ku80 is needed to resolve DSBs and that HR cannot compensate for a compromised NHEJ pathway in fully-grown oocytes. When higher levels of DNA damage were induced, a severe delay in M-phase entry was observed in oocytes lacking XRCC5 compared to wild-type oocytes, suggesting that Ku80-dependent repair of DNA damage is important for the timely release of oocytes from prophase I and resumption of meiosis. Ku80 was also found to be critical for chromosome integrity during meiotic maturation following etoposide exposure. These data demonstrate that Ku80, and NHEJ, are vital for quality control in mammalian GV stage oocytes and reveal that DNA repair pathway choice differs in meiotically arrested oocytes according to growth status.


Asunto(s)
Meiosis , Oocitos , Animales , Ratones , Daño del ADN , Reparación del ADN por Unión de Extremidades , Reparación del ADN , Etopósido/farmacología , Mamíferos , Oocitos/metabolismo
19.
Circ Cardiovasc Interv ; 16(7): e013080, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37357776

RESUMEN

BACKGROUND: Over the past decade, there has been substantial improvement in outcomes after transcatheter aortic valve replacement. Many patient and procedural factors have also changed over that time, making it challenging to untangle the drivers of those improvements. METHODS: Among patients who underwent transcatheter aortic valve replacement from 2012 to 2018 within the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapies Registry, we examined the relative contribution of changes in patient factors, device modifications, improving experience/skill, and advances in periprocedural care to the observed improvement in outcomes after transcatheter aortic valve replacement. Mediator clusters included demographics, noncardiovascular comorbidities, cardiovascular comorbidities, device-related factors, and nondevice-related procedural factors. Using logistic regression, we serially adjusted for the mediator clusters to examine the contribution of each to the observed improvement in outcomes over time. RESULTS: Among 161 196 patients treated with transcatheter aortic valve replacement at 596 sites, outcomes improved steadily from 2012 to 2018, including 30-day mortality (6.7% to 2.4%), 30-day composite adverse events (25.3% to 10.5%), and 1-year mortality (19.9% to 10.1%; all P<0.001). In sequential models, the unadjusted odds ratio for 30-day mortality was 0.82 per year (95% CI, 0.80-0.84), which was progressively attenuated with addition of each covariate cluster. Most of the improvement was explained by device factors and nondevice procedural factors. Results were similar for 30-day composite adverse events, although the observed temporal improvement was not fully explained by measured factors, suggesting improved technical skill as an additional mediator. In contrast to 30-day outcomes, each cluster of patient and procedural factors contributed similarly to the temporal improvement in 1-year mortality, indicating a greater impact of patient factors on longer-term outcomes. CONCLUSIONS: While US patients undergoing transcatheter aortic valve replacement have become younger, healthier, and lower risk over time, the most important factors contributing to improvements in short-term outcomes relate to advances in device technology and procedural factors, whereas changing patient characteristics had a greater impact on improvement in 1-year outcomes.


Asunto(s)
Estenosis de la Válvula Aórtica , Reemplazo de la Válvula Aórtica Transcatéter , Humanos , Estados Unidos , Resultado del Tratamiento , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/etiología , Factores de Riesgo , Sistema de Registros , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía
20.
JACC Cardiovasc Interv ; 16(12): 1437-1447, 2023 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-37380225

RESUMEN

Mitral regurgitation is the most common valvular disease and is estimated to affect over 5 million Americans. Real-world data collection contributes to safety and effectiveness evidence for the U.S. Food and Drug Administration, quality evaluation for the Centers for Medicare and Medicaid Services and hospitals, and clinical best practice research. We aimed to establish a minimum core data set in mitral interventions to promote efficient, reusable real-world data collection for all of these purposes. Two expert task forces separately evaluated and reconciled a list of candidate elements derived from: 1) 2 ongoing transcatheter mitral trials; and 2) a systemic literature review of high-impact mitral trials and U.S multicenter, multidevice registries. From 703 unique data elements considered, unanimous consensus agreement was achieved on 127 "core" data elements, with the most common reasons for exclusion from the minimum core data set being burden or difficulty in accurate assessment (41.2%), duplicative information (25.0%), and low likelihood of affecting outcomes (19.6%). After a systematic review and extensive discussions, a multilateral group of academicians, industry representatives, and regulators established and implemented into the national Society of Thoracic Surgery/American College of Cardiology Transcatheter Valve Therapies Registry 127 interoperable, reusable core data elements to support more efficient, consistent, and informative transcatheter mitral device evidence for regulatory submissions, safety surveillance, best practice development, and hospital quality assessments.


Asunto(s)
Cardiología , Medicare , Anciano , Humanos , Estados Unidos , Resultado del Tratamiento , Catéteres , Centers for Medicare and Medicaid Services, U.S. , Estudios Multicéntricos como Asunto
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