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1.
Am Heart J ; 258: 27-37, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36596333

RESUMEN

BACKGROUND: Transcatheter aortic valve replacement (TAVR) has become the standard of care for most patients with severe aortic stenosis (AS), but the impact of medical therapy prescribing patterns on post-TAVR patients has not been thoroughly investigated. METHODS: We analyzed Optum claims data from 9,012 adults who received TAVR for AS (January 2014-December 2018). Pharmacy claims data were used to identify patients who filled ACEI/ARB and/or statin prescriptions during the study's 90-day landmark period post-TAVR. Kaplan-Meier and adjusted Cox Proportional Hazards models were used to evaluate the association of prescribing patterns with mortality during the 3-year follow-up period. Subgroup analyses were performed to examine the impact of 11 potential confounders on the observed associations. RESULTS: A significantly lower adjusted 3-year mortality was observed for patients with post-TAVR prescription for ACEI/ARBs (hazard ratio [HR] = 0.82, 95% confidence interval [CI] 0.74-0.91, P = .0003) and statins (HR = 0.85, 95% CI 0.77-0.94, P = .0018) compared to patients who did not fill prescriptions for these medications post-TAVR. Subgroup analyses revealed that the survival benefit associated with ACEI/ARB prescription was not affected by any of the potential confounding variables, except preoperative ACEI/ARB prescription was associated with significantly lower risk of mortality vs postoperative prescription only. No other subgroup variables had significant interactions associated with survival benefits, including preoperative use of statins. CONCLUSIONS: In this large-scale, real-world analysis of patients undergoing TAVR, the prescription of ACEI/ARB and statins was associated with a significantly lower risk of mortality at 3-years, especially in those where the medications were initiated preoperatively.


Asunto(s)
Estenosis de la Válvula Aórtica , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Reemplazo de la Válvula Aórtica Transcatéter , Adulto , Humanos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Antagonistas de Receptores de Angiotensina/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Resultado del Tratamiento , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Válvula Aórtica/cirugía , Factores de Riesgo
2.
BMC Health Serv Res ; 23(1): 919, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37644525

RESUMEN

BACKGROUND: Insurance claims data have been used to inform an understanding of Lyme disease epidemiology and cost of care, however few such studies have incorporated post-treatment symptoms following diagnosis. Using longitudinal data from a private, employer-based health plan in an endemic US state, we compared outpatient care utilization pre- and post-Lyme disease diagnosis. We hypothesized that utilization would be higher in the post-diagnosis period, and that temporal trends would differ by age and gender. METHODS: Members with Lyme disease were required to have both a corresponding ICD-9 code and a fill of an antibiotic indicated for treatment of the infection within 30 days of diagnosis. A 2-year 'pre- diagnosis' period and a 2-year 'post-diagnosis period' were centered around the diagnosis month. Lyme disease-relevant outpatient care visits were defined as specific primary care, specialty care, or urgent care visits. Descriptive statistics examined visits during these pre- and post-diagnosis periods, and the association between these periods and the number of visits was explored using generalized linear mixed effects models adjusting for age, season of the year, and gender. RESULTS: The rate of outpatient visits increased 26% from the pre to the post-Lyme disease diagnosis periods among our 317-member sample (rate ratio = 1.26 [1.18, 1.36], p < 0.001). Descriptively, care utilization increases appeared to persist across months in the post-diagnosis period. Women's care utilization increased by 36% (1.36 [1.24, 1.50], p < 0.001), a significantly higher increase than the 14% increase found among men (1.14 [1.02, 1.27], p = 0.017). This gender difference was mainly driven by adult members. We found a borderline significant 17% increase in visits for children < 18 years, (1.17 [0.99, 1.38], p = 0.068), and a 31% increase for adults ≥ 18 years (1.31 [1.21, 1.42], p < 0.001). CONCLUSIONS: Although modest at the population level, the statistically significant increases in post-Lyme diagnosis outpatient care we observed were persistent and unevenly distributed across demographic and place of service categories. As Lyme disease cases continue to grow, so will the cumulative prevalence of persistent symptoms after treatment. Therefore, it will be important to confirm these findings and understand their significance for care utilization and cost, particularly against the backdrop of other post-acute infectious syndromes.


Asunto(s)
Enfermedad de Lyme , Medicina , Adulto , Niño , Masculino , Humanos , Femenino , Maryland/epidemiología , Pacientes Ambulatorios , Atención Ambulatoria , Enfermedad de Lyme/diagnóstico , Enfermedad de Lyme/epidemiología , Trastornos Post Infecciosos
3.
J Evol Biol ; 35(7): 934-947, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35716364

RESUMEN

Sexual signals are shaped by their intended and unintended receivers as well as the signalling environment. This interplay between sexual and natural selection can lead to divergence in signals in heterogeneous environments. Yet, the extent to which gene flow is restricted when signalling phenotypes vary across environments and over what spatial scales remains an outstanding question. In this study, we quantify gene flow between two colour morphs, red and black, of freshwater threespine stickleback fish (Gasterosteus aculeatus). We capitalize on the very recent divergence of signalling phenotypes in this system to characterize within-species and among-morph genetic variation and to test for levels of gene flow between colour morphs in Oregon and Washington. Despite limited evidence for assortative mating between allopatric red and black populations, we found that black populations are genetically distinct from nearby red populations and that the black morph appears to have evolved independently at least twice in Oregon and Washington. Surprisingly, we uncovered a group of stickleback in one small coastal stream, Connor Creek, which is genetically and morphologically distinct from the red and black colour morphs and from marine stickleback. Historically, both colour morphs have coexisted in this location and sometimes hybridized, raising new questions about the origins and history of these fish, which were first described as anadromous-black hybrids >50 years ago. Understanding how genetic variation is currently partitioned within and among populations and colour morphs in this system should prompt future studies to assess the relative roles of habitat, ecological and pre- and post-reproductive barriers in the genetic divergence and phenotypic patterns we observe in nature.


Asunto(s)
Smegmamorpha , Animales , Ecosistema , Peces , Flujo Génico , Flujo Genético , Selección Genética , Smegmamorpha/anatomía & histología , Smegmamorpha/genética
4.
Oecologia ; 200(3-4): 479-490, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36329313

RESUMEN

Litter decomposition is a central ecosystem function because dead plant biomass plays a critical role in carbon storage, the nitrogen (N) cycle, and as food/habitat for animals and microorganisms. In the face of global change, interactions between organisms that participate in litter decomposition are likely to change due to species loss and N pollution. To understand how these global change factors may interact to alter litter decomposition, we manipulated the detritivore community and N concentrations in a coastal salt marsh for 2 years. We chose to manipulate densities of a dominant, detritivorous snail (Melampus bidentatus) because its population size is expected to decline due to climate change, yet its impact on litter decomposition has not been tested in the field. We measured litter decomposition rates, detritivore densities, and the N concentrations of sediment and litter. We found that endogenous N enrichment (N added live plants before decomposition), exogenous N enrichment (N added to decomposing plants) and higher densities of Melampus increased litter decomposition rates. Linear mixed models further revealed that snails, other detritivores, and soil NH4+ were the best predictors of litter mass loss in the middle stages of decomposition. Notably, exogenous N added to litter already enriched with N further increased mass loss but did not increase litter %N. Our study reveals how global change in the form species loss and N pollution can have palpable impacts on carbon cycling and ecosystem function.


Asunto(s)
Gastrópodos , Humedales , Animales , Nitrógeno , Ecosistema , Contaminación Ambiental , Carbono
5.
Oecologia ; 192(3): 791-799, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32086561

RESUMEN

Numerous studies have found that predators can suppress prey densities and thereby impact important ecosystem processes such as plant productivity and decomposition. However, prey suppression by spiders can be highly variable. Unlike predators that feed on prey within a single energy channel, spiders often consume prey from asynchronous energy channels, such as grazing (live plant) and epigeic (soil surface) channels. Spiders undergo few life cycle changes and thus appear to be ideally suited to link energy channels, but ontogenetic diet shifts in spiders have received little attention. For example, spider use of different food channels may be highly specialized in different life stages and thus a species may be a multichannel omnivore only when we consider all life stages. Using stable isotopes, we investigated whether wolf spider (Pardosa littoralis, henceforth Pardosa) prey consumption is driven by changes in spider size. Small spiders obtained > 80% of their prey from the epigeic channel, whereas larger spiders used grazing and epigeic prey almost equally. Changes in prey consumption were not driven by changes in prey density, but by changes in prey use by different spider size classes. Thus, because the population size structure of Pardosa changes dramatically over the growing season, changes in spider size may have important implications for the strength of trophic cascades. Our research demonstrates that life history can be an important component of predator diet, which may in turn affect community- and ecosystem-level processes.


Asunto(s)
Cadena Alimentaria , Arañas , Animales , Ecosistema , Densidad de Población , Conducta Predatoria
6.
Mol Ecol ; 28(18): 4317-4334, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31483075

RESUMEN

Population divergence can occur due to mechanisms associated with geographic isolation and/or due to selection associated with different ecological niches. Much of the evidence for selection-driven speciation has come from studies of specialist insect herbivores that use different host plant species; however, the influence of host plant use on population divergence of generalist herbivores remains poorly understood. We tested how diet breadth, host plant species and geographic distance influence population divergence of the fall webworm (Hyphantria cunea; FW). FW is a broadly distributed, extreme generalist herbivore consisting of two morphotypes that have been argued to represent two different species: black-headed and red-headed. We characterized the differentiation of FW populations at two geographic scales. We first analysed the influence of host plant and geographic distance on genetic divergence across a broad continental scale for both colour types. We further analysed the influence of host plant, diet breadth and geographic distance on divergence at a finer geographic scale focusing on red-headed FW in Colorado. We found clear genetic and morphological distinction between red- and black-headed FW, and Colorado FW formed a genetic cluster distinct from other locations. Although both geographic distance and host plant use were correlated with genetic distance, geographic distance accounted for up to 3× more variation in genetic distance than did host plant use. As a rare study investigating the genetic structure of a widespread generalist herbivore over a broad geographic range (up to 3,000 km), our study supports a strong role for geographic isolation in divergence in this system.


Asunto(s)
Genética de Población , Geografía , Herbivoria/genética , Interacciones Huésped-Parásitos/genética , Mariposas Nocturnas/genética , Plantas/parasitología , Animales , Dieta , Mariposas Nocturnas/anatomía & histología , Filogenia , Estados Unidos
7.
Ecol Lett ; 21(1): 138-150, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29098754

RESUMEN

Primary consumers are under strong selection from resource ('bottom-up') and consumer ('top-down') controls, but the relative importance of these selective forces is unknown. We performed a meta-analysis to compare the strength of top-down and bottom-up forces on consumer fitness, considering multiple predictors that can modulate these effects: diet breadth, feeding guild, habitat/environment, type of bottom-up effects, type of top-down effects and how consumer fitness effects are measured. We focused our analyses on the most diverse group of primary consumers, herbivorous insects, and found that in general top-down forces were stronger than bottom-up forces. Notably, chewing, sucking and gall-making herbivores were more affected by top-down than bottom-up forces, top-down forces were stronger than bottom-up in both natural and controlled (cultivated) environments, and parasitoids and predators had equally strong top-down effects on insect herbivores. Future studies should broaden the scope of focal consumers, particularly in understudied terrestrial systems, guilds, taxonomic groups and top-down controls (e.g. pathogens), and test for more complex indirect community interactions. Our results demonstrate the surprising strength of forces exerted by natural enemies on herbivorous insects, and thus the necessity of using a tri-trophic approach when studying insect-plant interactions.


Asunto(s)
Herbivoria , Insectos , Animales , Ecosistema , Cadena Alimentaria
8.
Am J Epidemiol ; 187(10): 2202-2209, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29955850

RESUMEN

The epidemiology of Lyme disease has been examined utilizing insurance claims from privately insured individuals; however, it is unknown whether reported patterns vary among the publicly insured. We examined trends in incidence rates of first Lyme disease diagnosis among 384,652 Maryland Medicaid recipients enrolled from July 2004 to June 2011. Age-, sex-, county-, season-, and year-specific incidence rates were calculated, and mixed-effects multiple logistic regression models were used to study the relationship between Lyme disease diagnosis and these variables. The incidence rate in our sample was 97.65 cases per 100,000 person-years (95% confidence interval (CI): 91.53, 104.06), and there was a 13% average annual increase in the odds of a Lyme disease diagnosis (odds ratio = 1.13, 95% CI: 1.09, 1.17; P < 0.001). Incidence rates for males and females were not significantly different, though males were significantly more likely to be diagnosed during high-season months (relative risk (RR) = 1.24, 95% CI: 1.06, 1.44) and less likely to be diagnosed during low-season months (RR = 0.63, 95% CI: 0.46, 0.87) than females. Additionally, adults were significantly more likely than children to be diagnosed during low-season months (RR = 1.59, 95% CI: 1.19, 2.12). While relatively rare in this study sample, Lyme disease diagnoses do occur in a Medicaid population in a Lyme-endemic state.


Asunto(s)
Enfermedad de Lyme/epidemiología , Medicaid/estadística & datos numéricos , Adolescente , Adulto , Distribución por Edad , Niño , Preescolar , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Maryland/epidemiología , Persona de Mediana Edad , Oportunidad Relativa , Estaciones del Año , Distribución por Sexo , Estados Unidos , Adulto Joven
9.
Ecology ; 99(12): 2681-2691, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30289561

RESUMEN

Herbivore-plant interactions should be studied using a tri-trophic approach, but we lack a quantitative measure of the combined effect of top-down and bottom-up forces on herbivore fitness. We propose the combination of the bi-trophic fitness slopes as a tri-trophic fitness measure. We use the relationship between fitness associated with top-down and bottom-up forces and the frequency of host plant use to calculate the top-down and bottom-up fitness slopes, which we then combine to obtain three possible directions of tri-trophic slopes. A positive tri-trophic slope indicates that herbivores have overall greater tri-trophic fitness on the more frequently used hosts. A null tri-trophic fitness slope indicates that herbivores have similar fitness on all host plants. A negative tri-trophic slope indicates that herbivores have generally lower fitness on the more frequently used hosts. We tested the explanation power of our method using data from the literature that tested herbivore host shifts and experimentally using a generalist herbivore with variable diet breadth across populations. We found that in host shifts, herbivores have higher tri-trophic fitness on the novel host, while in generalist populations, herbivores use most frequently the best host available. We present applications in other research areas and consider the limitations of our approach. Our approach is a first step towards a comprehensive model of multiple selective forces acting on the evolution of interactions.


Asunto(s)
Herbivoria , Insectos , Animales , Dieta , Plantas
10.
Med Care ; 56(7): 603-609, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29781923

RESUMEN

BACKGROUND: Addressing both clinical and nonclinical determinants of health is essential for improving population health outcomes. In 2012, the Johns Hopkins Community Health Partnership (J-CHiP) implemented innovative population health management programs across acute and community environments. The community-based program involved multidisciplinary teams [ie, physicians, care managers (CM), health behavior specialists (HBS), community health workers, neighborhood navigators] and collaboration with community-based organizations to address social determinants. OBJECTIVES: To report the impact of a community-based program on cost and utilization from 2011 to 2016. DESIGN: Difference-in-difference estimates were calculated for an inclusive cohort of J-CHiP participants and matched nonparticipants. The analysis was replicated for participants with a CM and/or HBS to estimate the differential impact with more intensive program services. SUBJECTS: A total of 3268 high-risk Medicaid and Medicare beneficiaries (1634 total J-CHiP participants, 1365 with CM and 678 with HBS). OUTCOME MEASURES: Paid costs and counts of emergency department visits, admissions, and readmissions per member per year. RESULTS: For Medicaid, costs were almost $1200 per member per year lower for participants as a whole, $2000 lower for those with an HBS, and $3000 lower for those with a CM; hospital admission and readmission rates were 9%-26% lower for those with a CM and/or HBS. For Medicare, costs were lower (-$476), but utilization was similar or higher than nonparticipants. None of the observed Medicaid or Medicare differences were statistically significant. CONCLUSIONS: Although not statistically significant, the results indicate a promising innovation for Medicaid beneficiaries. For Medicare, the impact was negligible, indicating the need for further program modification.


Asunto(s)
Gastos en Salud/estadística & datos numéricos , Gestión de la Salud Poblacional , Evaluación de Programas y Proyectos de Salud/estadística & datos numéricos , Anciano , Servicio de Urgencia en Hospital/economía , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Hospitalización/economía , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Medicaid/estadística & datos numéricos , Medicare/estadística & datos numéricos , Persona de Mediana Edad , Readmisión del Paciente/estadística & datos numéricos , Determinantes Sociales de la Salud , Estados Unidos
11.
Oecologia ; 186(3): 711-718, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29383507

RESUMEN

Competition can have far-reaching consequences for insect fitness and dispersion. Time-lagged interspecific competition is known to negatively affect fitness, yet time-lagged intraspecific competition is rarely studied outside of outbreak conditions. We tested the impact of competition between larval cohorts of the western tent caterpillar (Malacosoma californicum) feeding on chokecherry (Prunus virginiana). We reared larvae on host plants that either had or did not have feeding damage from tent caterpillars the previous season to test the bottom-up fitness effects of intraspecific competition. We measured host-plant quality to test potential mechanisms for bottom-up effects and conducted field oviposition surveys to determine if female adult tent caterpillars avoided host plants with evidence of prior tent caterpillar presence. We found that time-lagged intraspecific competition impacted tent caterpillar fitness by reducing female pupal mass, which is a predictor of lifetime fitness. We found that plants that had been fed upon by tent caterpillars the previous season had leaves that were significantly tougher than plants that had not been fed upon by tent caterpillars, which may explain why female tent caterpillars suffered reduced fitness on these plants. Finally, we found that there were fewer tent caterpillar egg masses on plants that had tent caterpillars earlier in the season than plants without tent caterpillars, which suggests that adult females avoid these plants for oviposition. Our results confirm that intraspecific competition occurs among tent caterpillars and suggests that time-lagged intraspecific competition has been overlooked as an important component of insect fitness.


Asunto(s)
Lepidópteros , Animales , Femenino , Larva , Hojas de la Planta , Plantas , Estaciones del Año
13.
Oecologia ; 179(3): 741-51, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26099361

RESUMEN

Herbivore diet breadth is predicted to evolve in response to both bottom-up and top-down selective pressures, including host plant abundance, quality and natural enemy pressure. As the relative importance and strength of interactions change over an herbivore's geographic range, local patterns of host plant use should change in response, altering local diet breadths. Fall webworm (Hyphantria cunea) is a widespread, polyphagous moth species that feeds on hundreds of plant species worldwide. Populations of fall webworm in Colorado remain polyphagous, but their diet breadth is restricted compared to other populations and thus present an ideal opportunity to test the ecological drivers of host use by a polyphagous herbivore. We investigated how host abundance, larval performance, and parasitism affect host use for fall webworm to test how these selective pressures may act individually or in concert, as well as the role of any trade-offs among fitness components, to explain diet breadth and host use. We found that host abundance was a significant predictor of host use, which suggests a selective pressure to reduce search time for oviposition sites by adult females. We also detected an important trade-off between bottom-up and top-down selective pressures: higher quality host plants also had a greater proportion of larval mortality due to parasitism. Local patterns of host plant abundance appear to narrow the set of hosts used by fall webworms in Colorado, while the trade-off between host quality and risk of parasitism helps explain the maintenance of a generalized feeding strategy within this restricted set of hosts.


Asunto(s)
Herbivoria/fisiología , Mariposas Nocturnas/fisiología , Animales , Evolución Biológica , Colorado , Dieta , Femenino , Larva/parasitología , Larva/fisiología , Mariposas Nocturnas/parasitología , Oviposición , Plantas , Simbiosis
14.
Environ Entomol ; 53(1): 188-194, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38206676

RESUMEN

For herbivorous insects with a broad diet breadth, host plant identity can influence larval development by either accelerating or delaying growth. For some species of Lepidoptera, the number of larval instars varies depending on the host plant's identity. Fall webworm (Hyphantria cunea, Drury) is a polyphagous herbivore that feeds on over 450 host plants worldwide. Of the 2 morphotypes (red- and black-head) of fall webworm, the number of instars for the red-head fall webworms has not been characterized. Given its broad diet breadth, fall webworm developmental stages may vary with plant identity. We investigated whether host plant identity affected the number of instars observed during red-head fall webworm development. We measured the head capsules of over 6,000 fall webworm larvae reared on 6 different plants commonly eaten by fall webworms in Colorado. We modeled head capsule widths as Gaussian mixture models, with a Gaussian distribution that corresponded to each instar. We show that our red-head fall webworms varied in number of instars depending on the identity of their host plant upon which they fed. We found that red-head fall webworm exhibited 7 instars on 5 of the host plants and 8 instars on 1 host plant that we studied. Our results for the number of instars for red-head fall webworm are consistent with reports of the number of instars for black-head fall webworm. Our research provides insight into the influence of host plant identity on fall webworm development, which can be used to advance lab and field research of this species.


Asunto(s)
Herbivoria , Mariposas Nocturnas , Animales , Larva , Plantas , Dieta
15.
Innovations (Phila) ; 19(3): 274-282, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721804

RESUMEN

OBJECTIVE: Mitral valve repair (MVr) has become the standard therapy for degenerative mitral regurgitation (DMR), but real-world late mortality, reintervention, and readmission data are lacking. This study estimates MVr outcomes for DMR to 3 years in the Medicare fee-for-service population. METHODS: There were 4,219 DMR patients older than 65 years undergoing MVr within the Medicare 100% standard analytic file from October 2015 to December 2018 who were evaluated. Outcomes were analyzed for isolated MVr patients (n = 2,433) and patients undergoing MVr with certain concomitant procedures: MVr + tricuspid valve surgery (TVS; n = 619), MVr + cardiac ablation (CA; n = 540), and MVr + left atrial appendage closure (n = 627). Outcomes over a 3-year period included all-cause mortality, reintervention, rehospitalization, and common complications. All outcomes were modeled with adjustments for patient demographics and comorbid conditions. RESULTS: The average age for all patients was 71.9 ± 5.2 years. Adjusted all-cause mortality and MV reintervention (surgery or transcatheter) at 3 years for the primary cohort of isolated MVr was 3.5% and 1.6%, respectively. Directionally higher mortality at 3 years was observed in patients with concomitant TVS or CA. All-cause readmission and cardiac readmission for isolated MVr was 37.0% and 14.1%, with the highest rates for those with concomitant TVS or CA. Acute kidney injury and stroke/transient ischemic attack were the most common adverse events over 3 years for all patients. CONCLUSIONS: The 3-year mortality and reintervention rates in Medicare patients undergoing degenerative MVr are low. Those undergoing concomitant TVS or CA had directionally higher mortality and cardiac readmission rates. These results help refine outcome benchmarks as new transcatheter MVr procedures continue to emerge.


Asunto(s)
Medicare , Insuficiencia de la Válvula Mitral , Válvula Mitral , Readmisión del Paciente , Humanos , Insuficiencia de la Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/mortalidad , Anciano , Medicare/estadística & datos numéricos , Femenino , Masculino , Estados Unidos/epidemiología , Resultado del Tratamiento , Readmisión del Paciente/estadística & datos numéricos , Válvula Mitral/cirugía , Anciano de 80 o más Años , Complicaciones Posoperatorias/epidemiología , Implantación de Prótesis de Válvulas Cardíacas/estadística & datos numéricos , Implantación de Prótesis de Válvulas Cardíacas/mortalidad , Implantación de Prótesis de Válvulas Cardíacas/métodos , Estudios Retrospectivos
16.
Oecologia ; 171(2): 505-15, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22926724

RESUMEN

Multichannel omnivory by generalist predators, especially the use of both grazing and epigeic prey, has the potential to increase predator abundance and decrease herbivore populations. However, predator use of the epigeic web (soil surface detritus/microbe/algae consumers) varies considerably for reasons that are poorly understood. We therefore used a stable isotope approach to determine whether prey availability and predator hunting style (active hunting vs. passive web-building) impacted the degree of multichannel omnivory by the two most abundant predators on an intertidal salt marsh, both spiders. We found that carbon isotopic values of herbivores remained constant during the growing season, while values for epigeic feeders became dramatically more enriched such that values for the two webs converged in August. Carbon isotopic values for both spider species remained midway between the two webs as values for epigeic feeders shifted, indicating substantial use of prey from both food webs by both spider species. As the season progressed, prey abundance in the grazing food web increased while prey abundance in the epigeic web remained constant or declined. In response, prey consumption by the web-building spider shifted toward the grazing web to a much greater extent than did consumption by the hunting spider, possibly because passive web-capture is more responsive to changes in prey availability. Although both generalist predator species engaged in multichannel omnivory, hunting mode influenced the extent to which these predators used prey from the grazing and epigeic food webs, and could thereby influence the strength of trophic cascades in both food webs.


Asunto(s)
Cadena Alimentaria , Arañas , Animales , Bacterias , Isótopos de Carbono/análisis , Isótopos de Carbono/metabolismo , Herbivoria , Plantas , Conducta Predatoria , Estaciones del Año , Suelo , Humedales
17.
Ecology ; 104(3): e3957, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36519183

RESUMEN

The effects of competition can have far-reaching consequences for individuals, populations, and communities and therefore we should strive toward a deeper understanding of competitive interactions. In some cases, dietary generalists may be predicted to experience weak competition effects because of their ability to use a wide range of host plants. However, competition between insects frequently occurs indirectly, which can hinder insects' abilities to avoid competitive interactions. Therefore, competition may be as strong among dietary generalists as among dietary specialists. Yet competition between insects that are dietary generalists is infrequently studied. We tested for evidence of competitive interactions between two common, temporally separated, generalist insects: the western tent caterpillar (Malacosoma californicum), which feeds early in the season, and the fall webworm (Hyphantria cunea), which feeds later in the season. Both species frequently use a common host plant species (chokecherry) as a preferred host at our field sites. We tested the relative strength of bottom-up effects resulting from competitive interactions between these two generalists with laboratory-rearing trials at the relevant time of year for each insect. We recorded three common fitness measures (development time, pupal mass, and survival) for caterpillars reared on chokecherry with no damage from either of our focal species, with tent caterpillar damage, and with fall webworm damage. To test the strength of top-down pressures on fall webworm larval fitness and any potential interactions with bottom-up effects, we reared larvae in the field either exposed to or protected from predators on host plants that either did or did not have tent caterpillars feeding on them earlier in the season. We found evidence of bottom-up fitness effects on tent caterpillars and top-down and bottom-up fitness effects on fall webworms confirming that tent caterpillars and fall webworms compete indirectly. Tent caterpillars had lower pupal mass when reared on leaves from shrubs damaged by fall webworms. Fall webworms had lower pupal mass and longer development time when reared on leaves from shrubs damaged by tent caterpillars. In field trials, fall webworms reared on shrubs damaged by tent caterpillars had a lower survival and pupal mass. We show evidence of indirect competition in temporally separated generalists through leaf quality (bottom-up effects) and natural enemies (top-down effects).


Asunto(s)
Insectos , Mariposas Nocturnas , Humanos , Animales , Larva , Estaciones del Año , Plantas
18.
Philos Trans R Soc Lond B Biol Sci ; 378(1892): 20220365, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-37899018

RESUMEN

Ecological studies investigating the effects of artificial light at night (ALAN) have primarily focused on single or a few species, and seldom on community-level dynamics. As ALAN is a potential cause of insect and biodiversity declines, community-level perspectives are essential. We empirically tested the hypothesis that moth species differentially respond to ALAN and that these responses can cause shifts in community composition. We sampled moths from prairie fragments in Colorado, USA. We tested whether local light sources, sky glow, site area and/or vegetation affected moth community diversity. We found that increased sky glow decreased moth abundance and species richness and shifted community composition. Increased sky glow shifted moth community composition when light and bait traps were combined; notably this result appears to be driven entirely by moths sampled at bait traps, which is an unbiased sampling technique. Our results show that ALAN has significant effects on moth communities and that local light sources have contrasting effects on moth community composition compared to sky glow. It is imperative that we better understand the contrasting effects of types of ALAN to comprehend the overall impacts of light pollution on biodiversity declines. This article is part of the theme issue 'Light pollution in complex ecological systems'.


Asunto(s)
Mariposas Nocturnas , Animales , Mariposas Nocturnas/fisiología , Contaminación Lumínica , Ecosistema , Biodiversidad , Colorado
19.
Innovations (Phila) ; 18(4): 338-345, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37458243

RESUMEN

OBJECTIVE: Endoaortic balloon occlusion facilitates cardioplegic arrest during minimally invasive surgery (MIS). Studies have shown endoclamping to be as safe as traditional aortic clamping. We compared outcomes and hospital costs of endoclamping versus external aortic occlusion in a large administrative database. METHODS: There were 52,882 adults undergoing eligible cardiac surgery (October 2015 to March 2020) identified in the Premier Healthcare Database. Endoclamp procedures (n = 419) were 1:3 propensity score matched to similar procedures using external aortic occlusion (n = 1,244). Generalized linear modeling measured differences in in-hospital complications (major adverse renal and cardiac events, including mortality, new-onset atrial fibrillation, acute kidney injury [AKI], myocardial infarction [MI], postcardiotomy syndrome, stroke/transient ischemic attack [TIA], and aortic dissection) and length of stay (LOS). RESULTS: The mean age was 63 years, and 53% were male (n = 882). The majority (93%, n = 1,543) were mitral valve procedures, and 17% of procedures (n = 285) were robot-assisted. Total hospitalization costs were not statistically significantly different between the 2 groups ($52,158 vs $49,839, P = 0.06). The median LOS was significantly shorter in the endoclamp group (incident rate ratio = 0.87, P < 0.001). Mortality, atrial fibrillation, AKI, and stroke/TIA were similar between the 2 groups. MI and postcardiotomy syndrome were lower in the endoclamp group (odds ratio [OR] = 0.14, P = 0.006, and OR = 0.27, P = 0.005). There were no aortic dissections in the endoclamp group. CONCLUSIONS: Aortic endoclamping in MIS was associated with similar costs, shorter LOS, no dissections, and comparably low mortality and stroke rates when compared with external clamping in this hospital billing dataset. These results demonstrate the clinical safety and efficacy of endoaortic balloon clamping in a real-world setting. Further studies are warranted.


Asunto(s)
Lesión Renal Aguda , Fibrilación Atrial , Procedimientos Quirúrgicos Cardíacos , Ataque Isquémico Transitorio , Infarto del Miocardio , Accidente Cerebrovascular , Adulto , Humanos , Masculino , Persona de Mediana Edad , Femenino , Ataque Isquémico Transitorio/etiología , Procedimientos Quirúrgicos Cardíacos/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Lesión Renal Aguda/etiología , Resultado del Tratamiento , Estudios Retrospectivos
20.
Clinicoecon Outcomes Res ; 15: 349-360, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37223825

RESUMEN

Purpose: Heart failure (HF) is a serious public health burden that is rapidly increasing in the aging population. Valvular heart disease (VHD) is a known etiology of heart failure (HF); however, the impact of VHD on outcomes of patients with HF has not been well-studied in Japan. This study aimed to determine the rates of VHD in Japanese patients admitted for HF and explore associations of VHD with in-hospital outcomes through a claim-based analysis. Patients and methods: We analyzed claims data from 86,763 HF hospitalizations (January 2017 through December 2019) from the Medical Data Vision database. Common etiologies of HF were examined, then hospitalizations were categorized into those with VHD and those without. Covariate-adjusted models were used to explore the association of VHD with in-hospital mortality, length of stay, and medical cost. Results: Of 86,763 hospitalizations for HF, 13,183 had VHD and 73,580 did not. VHD was the second most frequent etiology of HF (15.2%). The most frequent type of VHD was mitral regurgitation (36.4% of all hospitalizations with VHD), followed by aortic stenosis (33.7%) and aortic regurgitation (16.4%). There was no significant difference in in-hospital mortality between hospitalizations with VHD vs those without (9.0% vs 8.9%; odds ratio [95% CI]: 1.01 [0.95-1.08]; p=0.723). Hospitalizations with VHD were associated with significantly longer length of stay (26.1 vs 24.8 days; incident rate ratio [95% CI]: 1.05 [1.03-1.07]; p<0.001) and higher medical costs (1536 vs 1195 thousand yen; rate ratio [95% CI]: 1.29 [1.25-1.32]; p<0.001). Conclusion: VHD was a frequent etiology of HF that was associated with significant medical resource use. Future studies are needed to investigate whether timely VHD treatment could reduce HF progression and its associated healthcare resource utilization.

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