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1.
Ecol Lett ; 27(2): e14371, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38361471

RESUMO

It is widely acknowledged that biodiversity change is affecting human well-being by altering the supply of Nature's Contributions to People (NCP). Nevertheless, the role of individual species in this relationship remains obscure. In this article, we present a framework that combines the cascade model from ecosystem services research with network theory from community ecology. This allows us to quantitatively link NCP demanded by people to the networks of interacting species that underpin them. We show that this "network cascade" framework can reveal the number, identity and importance of the individual species that drive NCP and of the environmental conditions that support them. This information is highly valuable in demonstrating the importance of biodiversity in supporting human well-being and can help inform the management of biodiversity in social-ecological systems.


Assuntos
Biodiversidade , Ecossistema , Humanos , Ecologia
2.
Nature ; 562(7725): 57-62, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30258229

RESUMO

The tundra is warming more rapidly than any other biome on Earth, and the potential ramifications are far-reaching because of global feedback effects between vegetation and climate. A better understanding of how environmental factors shape plant structure and function is crucial for predicting the consequences of environmental change for ecosystem functioning. Here we explore the biome-wide relationships between temperature, moisture and seven key plant functional traits both across space and over three decades of warming at 117 tundra locations. Spatial temperature-trait relationships were generally strong but soil moisture had a marked influence on the strength and direction of these relationships, highlighting the potentially important influence of changes in water availability on future trait shifts in tundra plant communities. Community height increased with warming across all sites over the past three decades, but other traits lagged far behind predicted rates of change. Our findings highlight the challenge of using space-for-time substitution to predict the functional consequences of future warming and suggest that functions that are tied closely to plant height will experience the most rapid change. They also reveal the strength with which environmental factors shape biotic communities at the coldest extremes of the planet and will help to improve projections of functional changes in tundra ecosystems with climate warming.


Assuntos
Aquecimento Global , Fenômenos Fisiológicos Vegetais , Plantas/anatomia & histologia , Tundra , Biometria , Mapeamento Geográfico , Umidade , Fenótipo , Solo/química , Análise Espaço-Temporal , Temperatura , Água/análise
3.
Proc Natl Acad Sci U S A ; 117(3): 1573-1579, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31907310

RESUMO

Land-use change is a major driver of biodiversity loss worldwide. Although biodiversity often shows a delayed response to land-use change, previous studies have typically focused on a narrow range of current landscape factors and have largely ignored the role of land-use history in shaping plant and animal communities and their functional characteristics. Here, we used a unique database of 220,000 land-use records to investigate how 20-y of land-use changes have affected functional diversity across multiple trophic groups (primary producers, mutualists, herbivores, invertebrate predators, and vertebrate predators) in 75 grassland fields with a broad range of land-use histories. The effects of land-use history on multitrophic trait diversity were as strong as other drivers known to impact biodiversity, e.g., grassland management and current landscape composition. The diversity of animal mobility and resource-acquisition traits was lower in landscapes where much of the land had been historically converted from grassland to crop. In contrast, functional biodiversity was higher in landscapes containing old permanent grasslands, most likely because they offer a stable and high-quality habitat refuge for species with low mobility and specialized feeding niches. Our study shows that grassland-to-crop conversion has long-lasting impacts on the functional biodiversity of agricultural ecosystems. Accordingly, land-use legacy effects must be considered in conservation programs aiming to protect agricultural biodiversity. In particular, the retention of permanent grassland sanctuaries within intensive landscapes may offset ecological debts.


Assuntos
Biodiversidade , Ecossistema , Pradaria , Agricultura , Animais , Conservação dos Recursos Naturais , Bases de Dados Factuais , Ecologia , Herbivoria/classificação , Invertebrados/classificação , Plantas/classificação , Densidade Demográfica
4.
Proc Natl Acad Sci U S A ; 117(45): 28140-28149, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33093203

RESUMO

Land-use intensification can increase provisioning ecosystem services, such as food and timber production, but it also drives changes in ecosystem functioning and biodiversity loss, which may ultimately compromise human wellbeing. To understand how changes in land-use intensity affect the relationships between biodiversity, ecosystem functions, and services, we built networks from correlations between the species richness of 16 trophic groups, 10 ecosystem functions, and 15 ecosystem services. We evaluated how the properties of these networks varied across land-use intensity gradients for 150 forests and 150 grasslands. Land-use intensity significantly affected network structure in both habitats. Changes in connectance were larger in forests, while changes in modularity and evenness were more evident in grasslands. Our results show that increasing land-use intensity leads to more homogeneous networks with less integration within modules in both habitats, driven by the belowground compartment in grasslands, while forest responses to land management were more complex. Land-use intensity strongly altered hub identity and module composition in both habitats, showing that the positive correlations of provisioning services with biodiversity and ecosystem functions found at low land-use intensity levels, decline at higher intensity levels. Our approach provides a comprehensive view of the relationships between multiple components of biodiversity, ecosystem functions, and ecosystem services and how they respond to land use. This can be used to identify overall changes in the ecosystem, to derive mechanistic hypotheses, and it can be readily applied to further global change drivers.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Modelos Biológicos , Florestas , Pradaria
5.
Sociology ; 57(3): 700-705, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38603248

RESUMO

How the COVID-19 pandemic, and the deaths that occurred during the acute phase of the pandemic (2020-2021), will be remembered is yet to be determined. Writing from a UK perspective, this short article reflects on the way in which memory, narratives and death are constructed, contested and (re)produced. Drawing on the authors' respective sociological sub-fields, it makes a case for an ongoing sociological appraisal of emergent COVID-19 narratives, that can encompass and intertwine understandings of temporality, accountability and loss.

6.
Nature ; 536(7617): 456-9, 2016 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-27533038

RESUMO

Many experiments have shown that loss of biodiversity reduces the capacity of ecosystems to provide the multiple services on which humans depend. However, experiments necessarily simplify the complexity of natural ecosystems and will normally control for other important drivers of ecosystem functioning, such as the environment or land use. In addition, existing studies typically focus on the diversity of single trophic groups, neglecting the fact that biodiversity loss occurs across many taxa and that the functional effects of any trophic group may depend on the abundance and diversity of others. Here we report analysis of the relationships between the species richness and abundance of nine trophic groups, including 4,600 above- and below-ground taxa, and 14 ecosystem services and functions and with their simultaneous provision (or multifunctionality) in 150 grasslands. We show that high species richness in multiple trophic groups (multitrophic richness) had stronger positive effects on ecosystem services than richness in any individual trophic group; this includes plant species richness, the most widely used measure of biodiversity. On average, three trophic groups influenced each ecosystem service, with each trophic group influencing at least one service. Multitrophic richness was particularly beneficial for 'regulating' and 'cultural' services, and for multifunctionality, whereas a change in the total abundance of species or biomass in multiple trophic groups (the multitrophic abundance) positively affected supporting services. Multitrophic richness and abundance drove ecosystem functioning as strongly as abiotic conditions and land-use intensity, extending previous experimental results to real-world ecosystems. Primary producers, herbivorous insects and microbial decomposers seem to be particularly important drivers of ecosystem functioning, as shown by the strong and frequent positive associations of their richness or abundance with multiple ecosystem services. Our results show that multitrophic richness and abundance support ecosystem functioning, and demonstrate that a focus on single groups has led to researchers to greatly underestimate the functional importance of biodiversity.


Assuntos
Biodiversidade , Cadeia Alimentar , Animais , Biomassa , Alemanha , Pradaria , Herbivoria , Insetos , Microbiologia , Modelos Biológicos , Plantas
7.
New Phytol ; 232(3): 1238-1249, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34346089

RESUMO

Though it is well established that species composition affects ecosystem function, the way in which species combine to control overall ecosystem functioning is still debated. In experimental mesocosms, we planted three functionally distinct dry-heath species in varying proportions and measured multiple ecosystem properties related to nutrient cycling and carbon storage (hereafter functions). Overall ecosystem functioning was described as the main axes of variation in ecosystem functioning (functional space) and the proportion of ecosystem functions at high levels; for example, fast carbon and nutrient cycling (cluster-based multifunctionality). The first functional space axis, related to nitrogen availability, was driven by plant species abundance, particularly that of legumes, which strongly affected many individual functions. The second, related to total plant biomass and woodiness, was mostly driven by the abundance of dwarf shrubs. Similarly, cluster-based multifunctionality was related to the initial abundance of all species, but particularly the legume. Interactions between species also affected ecosystem multifunctionality, but these effects were smaller in magnitude. These results indicate that species interactions could play a secondary role to species abundance and identity in driving the overall ecosystem functioning of heathlands, but also that axes of variation in functional space are clearly linked to plant functional composition.


Assuntos
Biodiversidade , Ecossistema , Biomassa , Carbono , Plantas , Solo
8.
Ecol Lett ; 22(1): 170-180, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30463104

RESUMO

While forest management strongly influences biodiversity, it remains unclear how the structural and compositional changes caused by management affect different community dimensions (e.g. richness, specialisation, abundance or completeness) and how this differs between taxa. We assessed the effects of nine forest features (representing stand structure, heterogeneity and tree composition) on thirteen above- and belowground trophic groups of plants, animals, fungi and bacteria in 150 temperate forest plots differing in their management type. Canopy cover decreased light resources, which increased community specialisation but reduced overall diversity and abundance. Features increasing resource types and diversifying microhabitats (admixing of oaks and conifers) were important and mostly affected richness. Belowground groups responded differently to those aboveground and had weaker responses to most forest features. Our results show that we need to consider forest features rather than broad management types and highlight the importance of considering several groups and community dimensions to better inform conservation.


Assuntos
Biodiversidade , Árvores , Animais , Fungos
9.
J Surg Res ; 243: 41-46, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31154131

RESUMO

BACKGROUND: Studies comparing percutaneous closure of patent ductus arteriosus (PDA) with surgical ligation tend to exclude premature infants and have not assessed procedural charges. We compared our contemporary outcomes and charges of device closure to surgical ligation of PDA in preterm infants. MATERIAL AND METHODS: Preterm infants who underwent isolated PDA closure during their newborn hospitalization (January 2014 to September 2017) were grouped based on intention to treat (surgery versus device closure). Patient demographics, procedural details, and immediate postprocedural outcomes were compared. Procedural charges for device closure versus surgical ligation were compared. RESULTS: Compared with the device group (n = 33), patients undergoing surgical ligation (n = 39) were younger, smaller, and required more preoperative support (P < 0.05). The procedure time was shorter for surgical ligation (P < 0.01). Although there was no procedural mortality in either group, the complication rate was higher for device closure than for surgical ligation (15.2% versus 0%; P = 0.02). The proportion of patients returning to preprocedural respiratory support by 48 h after procedure was similar. There was a higher proportion of surgical patients who required increased inotropic support in the first 24 h after procedure (P = 0.19). The procedural charges for transcatheter device closure were twice as expensive as those for surgical ligation. CONCLUSIONS: In our early experience with percutaneous PDA closure, we found a percutaneous approach in preterm infants feasible and well tolerated. Both surgical ligation and device closure were associated with perioperative or postoperative complications. Procedural charges were higher for percutaneous closure, driven by device charge and catheterization room utilization. Further investigation is needed to establish guidelines for first-line therapy for PDA closure in preterm infants, including cost-benefit analysis.


Assuntos
Cateterismo Cardíaco/métodos , Procedimentos Cirúrgicos Cardíacos/métodos , Permeabilidade do Canal Arterial/terapia , Doenças do Prematuro/terapia , Cateterismo Cardíaco/instrumentação , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Análise de Intenção de Tratamento , Ligadura , Masculino , Estudos Retrospectivos , Resultado do Tratamento
10.
Ecol Lett ; 21(1): 31-42, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29143494

RESUMO

Humans require multiple services from ecosystems, but it is largely unknown whether trade-offs between ecosystem functions prevent the realisation of high ecosystem multifunctionality across spatial scales. Here, we combined a comprehensive dataset (28 ecosystem functions measured on 209 forest plots) with a forest inventory dataset (105,316 plots) to extrapolate and map relationships between various ecosystem multifunctionality measures across Europe. These multifunctionality measures reflected different management objectives, related to timber production, climate regulation and biodiversity conservation/recreation. We found that trade-offs among them were rare across Europe, at both local and continental scales. This suggests a high potential for 'win-win' forest management strategies, where overall multifunctionality is maximised. However, across sites, multifunctionality was on average 45.8-49.8% below maximum levels and not necessarily highest in protected areas. Therefore, using one of the most comprehensive assessments so far, our study suggests a high but largely unrealised potential for management to promote multifunctional forests.


Assuntos
Biodiversidade , Ecossistema , Florestas , Clima , Europa (Continente) , Humanos
11.
New Phytol ; 219(2): 574-587, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29672854

RESUMO

We lack strong empirical evidence for links between plant attributes (plant community attributes and functional traits) and the distribution of soil microbial communities at large spatial scales. Using datasets from two contrasting regions and ecosystem types in Australia and England, we report that aboveground plant community attributes, such as diversity (species richness) and cover, and functional traits can predict a unique portion of the variation in the diversity (number of phylotypes) and community composition of soil bacteria and fungi that cannot be explained by soil abiotic properties and climate. We further identify the relative importance and evaluate the potential direct and indirect effects of climate, soil properties and plant attributes in regulating the diversity and community composition of soil microbial communities. Finally, we deliver a list of examples of common taxa from Australia and England that are strongly related to specific plant traits, such as specific leaf area index, leaf nitrogen and nitrogen fixation. Together, our work provides new evidence that plant attributes, especially plant functional traits, can predict the distribution of soil microbial communities at the regional scale and across two hemispheres.


Assuntos
Geografia , Microbiota , Plantas/microbiologia , Microbiologia do Solo , Algoritmos , Austrália , Bactérias/classificação , Biodiversidade , Inglaterra , Fungos/classificação , Modelos Teóricos
12.
Int J Qual Health Care ; 30(7): 571-575, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29635400

RESUMO

OBJECTIVE: There has been an increase in the number and complexity of patient complaints against healthcare institutions. An understanding of the resources needed in this area is important for proper planning. DESIGN: Cohort study. SETTING: A 1250-bed tertiary-care teaching hospital. PARTICIPANTS: All patient complaints received between 1 February 2014 and 31 January 2015 were prospectively included in this cohort study. MAIN OUTCOME MEASURES: The amount of time spent on the investigation and liaising with the complainant for each case was recorded. The complainant's personal details and characteristics were recorded anonymously. RESULTS: In total, 908 patient complaints were recorded from 801 individuals during the study period. Longer median person-hours were spent on managing complaints that were brought forward by men (1.48 h), those who were distant relatives of the patients (2.08 h), foreigners (1.58 h) and non-subsidised patients (1.83 h). Patient complaints falling into the categories of clinical domain (3.00 h) and patient rights (2.54 h), quality (3.00 h) and safety (2.83 h) required the longest median time to manage. Multiple logistic regression analysis revealed that the total amount of time spent on the complaints was predicted by the gender of the complainant, the relationship of the complainant with the patient, the subsidy status of the patient, the severity and the domain of the complaint. CONCLUSIONS: This study reported the time required to manage patient complaints in a larger tertiary-care academic medical centre. Predictors of the time spent on resolving patient complaints can be used as parameters for resource planning.


Assuntos
Administração Hospitalar/métodos , Hospitais de Ensino/organização & administração , Satisfação do Paciente , Estudos de Coortes , Emigrantes e Imigrantes/estatística & dados numéricos , Família , Feminino , Financiamento Governamental/estatística & dados numéricos , Humanos , Masculino , Estudos Prospectivos , Fatores Sexuais , Estudos de Tempo e Movimento
13.
Cardiol Young ; 28(8): 1031-1036, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29925455

RESUMO

BACKGROUND: Although interstage mortality for infants with hypoplastic left heart syndrome has declined within the National Pediatric Cardiology Quality Improvement Collaborative, variation across centres persists. It remains unclear whether centres with lower interstage mortality have lower-risk patients or whether differences in care may explain this variation. We examined previously established risk factors across National Pediatric Cardiology Quality Improvement Collaborative centres with lower and higher interstage mortality rates. METHODS: Lower-mortality centres were defined as those with >25 consecutive interstage survivors. Higher-mortality centres were defined as those with cumulative interstage mortality rates >10%, which is a collaborative historic baseline rate. Baseline risk factors and perioperative characteristics were compared. RESULTS: Seven lower-mortality centres were identified (n=331 patients) and had an interstage mortality rate of 2.7%, as compared with 13.3% in the four higher-mortality centres (n=173 patients, p<0.0001). Of all baseline risk factors examined, the only factor that differed between the lower- and higher-mortality centres was postnatal diagnosis (18.4 versus 31.8%, p=0.001). In multivariable analysis, there remained a significant mortality difference between the two groups of centres after adjusting for this variable: adjusted mortality rate was 2.8% in lower-mortality centres compared with 12.6% in higher-mortality centres, p=0.003. Secondary analyses identified multiple differences between groups in perioperative practices and other variables. CONCLUSIONS: Variation in interstage mortality rates between these two groups of centres does not appear to be explained by differences in baseline risk factors. Further study is necessary to evaluate variation in care practices to identify targets for improvement efforts.


Assuntos
Cardiologia/organização & administração , Cuidados Críticos/normas , Síndrome do Coração Esquerdo Hipoplásico/mortalidade , Assistência Perioperatória/normas , Melhoria de Qualidade/organização & administração , Comportamento Cooperativo , Feminino , Humanos , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Análise Multivariada , Sistema de Registros , Fatores de Risco , Resultado do Tratamento , Estados Unidos/epidemiologia
14.
J Allergy Clin Immunol ; 140(4): 950-958, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28602936

RESUMO

BACKGROUND: Allergic rhinitis (AR) affects 10% to 40% of the population. It reduces quality of life and school and work performance and is a frequent reason for office visits in general practice. Medical costs are large, but avoidable costs associated with lost work productivity are even larger than those incurred by asthma. New evidence has accumulated since the last revision of the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines in 2010, prompting its update. OBJECTIVE: We sought to provide a targeted update of the ARIA guidelines. METHODS: The ARIA guideline panel identified new clinical questions and selected questions requiring an update. We performed systematic reviews of health effects and the evidence about patients' values and preferences and resource requirements (up to June 2016). We followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) evidence-to-decision frameworks to develop recommendations. RESULTS: The 2016 revision of the ARIA guidelines provides both updated and new recommendations about the pharmacologic treatment of AR. Specifically, it addresses the relative merits of using oral H1-antihistamines, intranasal H1-antihistamines, intranasal corticosteroids, and leukotriene receptor antagonists either alone or in combination. The ARIA guideline panel provides specific recommendations for the choice of treatment and the rationale for the choice and discusses specific considerations that clinicians and patients might want to review to choose the management most appropriate for an individual patient. CONCLUSIONS: Appropriate treatment of AR might improve patients' quality of life and school and work productivity. ARIA recommendations support patients, their caregivers, and health care providers in choosing the optimal treatment.


Assuntos
Antialérgicos/uso terapêutico , Asma/prevenção & controle , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Rinite Alérgica/tratamento farmacológico , Animais , Criança , Tomada de Decisão Clínica , Prática Clínica Baseada em Evidências , Humanos , Qualidade de Vida , Rinite Alérgica/epidemiologia
15.
Proc Natl Acad Sci U S A ; 111(40): 14478-83, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25246582

RESUMO

Ecosystem management policies increasingly emphasize provision of multiple, as opposed to single, ecosystem services. Management for such "multifunctionality" has stimulated research into the role that biodiversity plays in providing desired rates of multiple ecosystem processes. Positive effects of biodiversity on indices of multifunctionality are consistently found, primarily because species that are redundant for one ecosystem process under a given set of environmental conditions play a distinct role under different conditions or in the provision of another ecosystem process. Here we show that the positive effects of diversity (specifically community composition) on multifunctionality indices can also arise from a statistical fallacy analogous to Simpson's paradox (where aggregating data obscures causal relationships). We manipulated soil faunal community composition in combination with nitrogen fertilization of model grassland ecosystems and repeatedly measured five ecosystem processes related to plant productivity, carbon storage, and nutrient turnover. We calculated three common multifunctionality indices based on these processes and found that the functional complexity of the soil communities had a consistent positive effect on the indices. However, only two of the five ecosystem processes also responded positively to increasing complexity, whereas the other three responded neutrally or negatively. Furthermore, none of the individual processes responded to both the complexity and the nitrogen manipulations in a manner consistent with the indices. Our data show that multifunctionality indices can obscure relationships that exist between communities and key ecosystem processes, leading us to question their use in advancing theoretical understanding--and in management decisions--about how biodiversity is related to the provision of multiple ecosystem services.


Assuntos
Biodiversidade , Ecossistema , Plantas/metabolismo , Solo/química , Animais , Biomassa , Pradaria , Ciclo do Nitrogênio , Plantas/classificação , Dinâmica Populacional , Solo/parasitologia , Microbiologia do Solo
16.
Ecol Lett ; 18(8): 790-798, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26032242

RESUMO

Intransitive competition networks, those in which there is no single best competitor, may ensure species coexistence. However, their frequency and importance in maintaining diversity in real-world ecosystems remain unclear. We used two large data sets from drylands and agricultural grasslands to assess: (1) the generality of intransitive competition, (2) intransitivity-richness relationships and (3) effects of two major drivers of biodiversity loss (aridity and land-use intensification) on intransitivity and species richness. Intransitive competition occurred in > 65% of sites and was associated with higher species richness. Intransitivity increased with aridity, partly buffering its negative effects on diversity, but was decreased by intensive land use, enhancing its negative effects on diversity. These contrasting responses likely arise because intransitivity is promoted by temporal heterogeneity, which is enhanced by aridity but may decline with land-use intensity. We show that intransitivity is widespread in nature and increases diversity, but it can be lost with environmental homogenisation.


Assuntos
Biodiversidade , Modelos Biológicos , Plantas/classificação , Agricultura , Mudança Climática , Alemanha , Pradaria
18.
Pediatr Res ; 74(1): 61-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23575878

RESUMO

BACKGROUND: Hypoplastic left heart syndrome (HLHS) is associated with significant mortality and morbidity. Fetal head growth abnormalities have been identified in a subset of HLHS fetuses, but it is unclear whether specific patterns of maladaptive growth affect clinical outcomes. We hypothesized that poor fetal head growth is associated with an increased frequency of adverse clinical outcomes. METHODS: We retrospectively examined a cohort of HLHS patients from midgestation to 1 y of age. Fetal and birth anthropometric measurements were analyzed using the Olsen standard, and clinical outcomes were obtained. RESULTS: A total of 104 HLHS patients were identified over a 12-y period; fetal data were available in 38 cases. HLHS neonates demonstrated a high incidence of microcephaly (12%), small head size (27%), and poor head growth (32%). All-cause mortality was 31% at 30 d and 43% at 1 y. Neurologic outcomes were observed in 12% of patients and were significantly increased with microcephaly (43 vs. 4%; P = 0.02). The average length of hospital stay following stage I palliation was 33.4 ± 33 d, correcting for early death. CONCLUSION: In term nonsyndromic HLHS, fetal and neonatal microcephaly are associated with early adverse neurologic outcomes but not mortality.


Assuntos
Síndrome do Coração Esquerdo Hipoplásico/complicações , Microcefalia/complicações , Feminino , Humanos , Síndrome do Coração Esquerdo Hipoplásico/fisiopatologia , Lactente , Tempo de Internação , Masculino , Microcefalia/fisiopatologia , Estudos Retrospectivos
19.
Pediatr Crit Care Med ; 14(5): e218-24, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23439467

RESUMO

BACKGROUND AND OBJECTIVES: Evaluate risk factors for and impact of acute kidney injury on children following the arterial switch operation. DESIGN: Single-center retrospective chart review. SETTING: A tertiary children's hospital. PATIENTS: A total of 92 patients receiving the arterial switch operation from 1997 to 2008 at severe acute kidney injury was defined as a 100% serum creatinine rise over baseline. RESULTS: Of 92 patients, 18 (20%) developed severe acute kidney injury. Neither patient age or weight nor cardiopulmonary bypass time correlated with the development of acute kidney injury. Acute kidney injury was associated with the following: higher postoperative day 1 (POD1) fluid balance, higher inotrope scores (POD1 and POD2), and longer: postoperative ICU length of stay (p = 0.005), overall ICU length of stay (p = 0.05), and postoperative hospital length of stay (p = 0.006). The time to peak creatinine for acute kidney injury patients was between POD1 and POD2. Correction of serum creatinine for fluid balance increased the population defined as severe acute kidney injury and strengthened the association of acute kidney injury with postoperative morbidity. CONCLUSIONS: Acute kidney injury following the arterial switch operation is associated with increased morbidity. In this single center, single population, and homogenous cohort of patients, the development of acute kidney injury was not correlated with age, size, or cardiopulmonary bypass time, but was still associated with prolonged duration of ventilation and hospitalization. Notably, the failure to correct serum creatinine for fluid balance underestimates the prevalence and impact of acute kidney injury.


Assuntos
Injúria Renal Aguda/etiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar/efeitos adversos , Creatina/sangue , Complicações Pós-Operatórias/sangue , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/mortalidade , Análise de Variância , Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos Cirúrgicos Cardíacos/mortalidade , Ponte Cardiopulmonar/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Recém-Nascido , Tempo de Internação , Masculino , Morbidade , Estudos Retrospectivos
20.
J Assist Reprod Genet ; 30(8): 1009-15, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24052330

RESUMO

PURPOSE: To determine the pattern of expression of parathyroid hormone-related protein (PTHrP) and its receptor, parathyroid hormone receptor 1 (PTHR1), in mouse embryos in different stages of preimplantation development. METHODS: Embryos were cultured from the pronuclear zygote stage and harvested as 2-cell, 4-cell and 8-cell embryos, morulae and blastocysts. RT-PCR was carried out on mRNAs of these and of trophoblast outgrowths for detection of PTHrP and PTHR1. Whole mounted embryos intact or stripped of zonae pellucidae were immunofluorescently stained for PTHrP and PTH receptor and observed with confocal microscopy. RESULTS: PTHrP mRNA was present in the pronuclear zygote, not present in 2-cell, 4-cell and uncompacted 8-cell embryos, present in the 8-cell compacting embryo, and not detected in 16-cell morulae or blastocysts. The mRNA was present in trophoblasts growing on fibronectin beds. mRNA for PTHR1 was detected in the pronuclear zygote, then undetected until the compacted 8-cell stage and thereafter. PTH receptor protein was observed in 2-cell embryos, morulae and in the inner cell mass and trophectoderm of blastocysts. PTHrP was observed dispersed in the cytoplasm of 2-cell, 4-cell and uncompacted 8-cell embryos, and in distinct foci near the nuclei of morulae. In blastocysts, PTHrP appeared on the apical surface of only trophoblast cells which had extruded from the zona pellucida. Fully hatched blastocysts expressed the protein on the apical side of all trophoblasts. When morulae were prematurely stripped of their zonae, PTHrP was observed on the embryos' outer surface. CONCLUSIONS: PTHrP protein is expressed throughout early embryo development, and its receptor PTHR1 is expressed from the morula stage. Embryo hatching is associated with translocation of PTHrP to the apical plasma membrane of trophoblasts. PTHrP may thus have autocrine effects on the developing blastocyst.


Assuntos
Blastocisto/metabolismo , Desenvolvimento Embrionário , Proteína Relacionada ao Hormônio Paratireóideo/análise , Animais , Camundongos , Proteína Relacionada ao Hormônio Paratireóideo/genética , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Transporte Proteico , Zona Pelúcida/metabolismo , Zona Pelúcida/ultraestrutura
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