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1.
JAMA Pediatr ; 178(2): 193-195, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38048098

RESUMO

This cohort study evaluates changes in pediatric speech delay diagnoses before and after the COVID-19 pandemic.


Assuntos
Transtornos do Desenvolvimento da Linguagem , Projetos de Pesquisa , Humanos , Criança , Pandemias
2.
Vaccine ; 41(15): 2447-2455, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36803895

RESUMO

BACKGROUND: The successful development of multiple COVID-19 vaccines has led to a global vaccination effort to reduce severe COVID-19 infection and mortality. However, the effectiveness of the COVID-19 vaccines wane over time leading to breakthrough infections where vaccinated individuals experience a COVID-19 infection. Here we estimate the risks of breakthrough infection and subsequent hospitalization in individuals with common comorbidities who had completed an initial vaccination series. METHODS: Our study population included vaccinated patients between January 1, 2021 to March 31, 2022 who are present in the Truveta patient population. Models were developed to describe 1) time from completing primary vaccination series till breakthrough infection; and 2) if a patient was hospitalized within 14 days of breakthrough infection. We adjusted for age, race, ethnicity, sex, and year-month of vaccination. RESULTS: Of 1,218,630 patients in the Truveta Platform who had completed an initial vaccination sequence between January 1, 2021 and March 31, 2022, 2.85, 3.42, 2.75, and 2.88 percent of patients with CKD, chronic lung disease, diabetes, or are in an immunocompromised state experienced breakthrough infection, respectively, compared to 1.46 percent of the population without any of these four comorbidities. We found an increased risk of breakthrough infection and subsequent hospitalization in individuals with any of the four comorbidities when compared to individuals without these four comorbidities. CONCLUSIONS: Vaccinated individuals with any of the studied comorbidities experienced an increased risk of breakthrough COVID-19 infection and subsequent hospitalizations compared to the people without any of the studied comorbidities. Individuals with immunocompromising conditions and chronic lung disease were most at risk of breakthrough infection, while people with CKD were most at risk of hospitalization following breakthrough infection. Patients with multiple comorbidities have an even greater risk of breakthrough infection or hospitalization compared to patients with none of the studied comorbidities. Individuals with common comorbidities should remain vigilant against infection even if vaccinated.


Assuntos
COVID-19 , Insuficiência Renal Crônica , Humanos , COVID-19/epidemiologia , Vacinas contra COVID-19 , Infecções Irruptivas , Hospitalização , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia
3.
Front Public Health ; 10: 1074775, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36711416

RESUMO

Introduction: Demonstrated health inequalities persist in the United States. SARS-CoV-2 (COVID) has been no exception, with access to treatment and hospitalization differing across race or ethnic groups. Here, we aim to assess differences in treatment with remdesivir and hospital length of stay across the four waves of the pandemic. Materials and methods: Using a subset of the Truveta data, we examine the odds ratio (OR) of in-hospital remdesivir treatment and risk ratio (RR) of in-hospital length of stay between Black or African American (Black) to White patients. We adjusted for confounding factors, such as age, sex, and comorbidity status. Results: There were statistically significant lower rates of remdesivir treatment and longer in-hospital length of stay comparing Black patients to White patients early in the pandemic (OR for treatment: 0.88, 95% confidence interval [CI]: 0.80, 0.96; RR for length of stay: 1.17, CI: 1.06, 1.21). Rates became close to parity between groups as the pandemic progressed. Conclusion: While inpatient remdesivir treatment rates increased and length of stay decreased over the beginning course of the pandemic, there are still inequalities in patient care.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Estados Unidos/epidemiologia , COVID-19/epidemiologia , Tempo de Internação , População Branca , Hospitais
4.
Proc Natl Acad Sci U S A ; 114(14): 3666-3671, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28325881

RESUMO

Inferring large-scale processes that drive biodiversity hinges on understanding the phylogenetic and spatial pattern of species richness. However, clades and geographic regions are accumulating newly described species at an uneven rate, potentially affecting the stability of currently observed diversity patterns. Here, we present a probabilistic model of species discovery to assess the uncertainty in diversity levels among clades and regions. We use a Bayesian time series regression to estimate the long-term trend in the rate of species description for marine bivalves and find a distinct spatial bias in the accumulation of new species. Despite these biases, probabilistic estimates of future species richness show considerable stability in the currently observed rank order of regional diversity. However, absolute differences in richness are still likely to change, potentially modifying the correlation between species numbers and geographic, environmental, and biological factors thought to promote biodiversity. Applied to scallops and related clades, we find that accumulating knowledge of deep-sea species will likely shift the relative richness of these three families, emphasizing the need to consider the incomplete nature of bivalve taxonomy in quantitative studies of its diversity. Along with estimating expected changes to observed patterns of diversity, the model described in this paper pinpoints geographic areas and clades most urgently requiring additional systematic study-an important practice for building more complete and accurate models of biodiversity dynamics that can inform ecological and evolutionary theory and improve conservation practice.


Assuntos
Bivalves/fisiologia , Modelos Estatísticos , Animais , Teorema de Bayes , Biodiversidade , Evolução Biológica , Bivalves/classificação , Modelos Biológicos , Filogenia , Dinâmica Populacional
5.
Proc Natl Acad Sci U S A ; 112(42): 13015-20, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26438873

RESUMO

Determining which biological traits influence differences in extinction risk is vital for understanding the differential diversification of life and for making predictions about species' vulnerability to anthropogenic impacts. Here I present a hierarchical Bayesian survival model of North American Cenozoic mammal species durations in relation to species-level ecological factors, time of origination, and phylogenetic relationships. I find support for the survival of the unspecialized as a time-invariant generalization of trait-based extinction risk. Furthermore, I find that phylogenetic and temporal effects are both substantial factors associated with differences in species durations. Finally, I find that the estimated effects of these factors are partially incongruous with how these factors are correlated with extinction risk of the extant species. These findings parallel previous observations that background extinction is a poor predictor of mass extinction events and suggest that attention should be focused on mass extinctions to gain insight into modern species loss.


Assuntos
Mamíferos , Animais , Teorema de Bayes , Biodiversidade , Evolução Biológica , Filogenia
6.
Syst Biol ; 63(4): 582-600, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24817532

RESUMO

Morphological characters are indispensable in phylogenetic analyses for understanding the pattern, process, and tempo of evolution. If characters are independent and free of systematic errors, then combining as many different kinds of characters as are available will result in the best-supported phylogenetic hypotheses. But since morphological characters are subject to natural selection for function and arise from the expression of developmental pathways, they may not be independent, a situation that may amplify any underlying homoplasy. Here, we use new dental and multi-locus genetic data from bats (Mammalia: Chiroptera) to quantify saturation and similarity in morphological characters and introduce two likelihood-based approaches to identify strongly conflicting characters and integrate morphological and molecular data. We implement these methods to analyze the phylogeny of incomplete Miocene fossils in the radiation of Phyllostomidae (New World Leaf-nosed Bats), perhaps the most ecologically diverse family of living mammals. Morphological characters produced trees incongruent with molecular phylogenies, were saturated, and showed rates of change higher than most molecular substitution rates. Dental characters encoded variation similar to that in other morphological characters, while molecular characters encoded highly dissimilar variation in comparison. Saturation and high rates of change indicate randomization of phylogenetic signal in the morphological data, and extensive similarity suggests characters are non-independent and errors are amplified. To integrate the morphological data into tree building while accounting for homoplasy, we used statistical molecular scaffolds and combined phylogenetic analyses excluding a small subset of strongly conflicting dental characters. The phylogenies revealed the Miocene nectar-feeding †Palynephyllum nests within the crown nectar-feeding South American subfamily Lonchophyllinae, while the Miocene genus †Notonycteris is sister to the extant carnivorous Vampyrum. These relationships imply new calibration points for timing of radiation of the ecologically diverse Phyllostomidae. [Chiroptera; conflict; dentition; morphology; Phyllostomidae; saturation; scaffold; systematic error.].


Assuntos
Quirópteros/anatomia & histologia , Quirópteros/classificação , Fósseis , Filogenia , Animais , Quirópteros/genética , Classificação , Éxons/genética , Genes Mitocondriais/genética , Íntrons/genética , Dados de Sequência Molecular , Dente/anatomia & histologia
7.
PLoS One ; 8(1): e53873, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23342027

RESUMO

BACKGROUND: Crocodilians exhibit a spectrum of rostral shape from long snouted (longirostrine), through to short snouted (brevirostrine) morphologies. The proportional length of the mandibular symphysis correlates consistently with rostral shape, forming as much as 50% of the mandible's length in longirostrine forms, but 10% in brevirostrine crocodilians. Here we analyse the structural consequences of an elongate mandibular symphysis in relation to feeding behaviours. METHODS/PRINCIPAL FINDINGS: Simple beam and high resolution Finite Element (FE) models of seven species of crocodile were analysed under loads simulating biting, shaking and twisting. Using beam theory, we statistically compared multiple hypotheses of which morphological variables should control the biomechanical response. Brevi- and mesorostrine morphologies were found to consistently outperform longirostrine types when subject to equivalent biting, shaking and twisting loads. The best predictors of performance for biting and twisting loads in FE models were overall length and symphyseal length respectively; for shaking loads symphyseal length and a multivariate measurement of shape (PC1- which is strongly but not exclusively correlated with symphyseal length) were equally good predictors. Linear measurements were better predictors than multivariate measurements of shape in biting and twisting loads. For both biting and shaking loads but not for twisting, simple beam models agree with best performance predictors in FE models. CONCLUSIONS/SIGNIFICANCE: Combining beam and FE modelling allows a priori hypotheses about the importance of morphological traits on biomechanics to be statistically tested. Short mandibular symphyses perform well under loads used for feeding upon large prey, but elongate symphyses incur high strains under equivalent loads, underlining the structural constraints to prey size in the longirostrine morphotype. The biomechanics of the crocodilian mandible are largely consistent with beam theory and can be predicted from simple morphological measurements, suggesting that crocodilians are a useful model for investigating the palaeobiomechanics of other aquatic tetrapods.


Assuntos
Jacarés e Crocodilos/anatomia & histologia , Jacarés e Crocodilos/fisiologia , Mandíbula/anatomia & histologia , Mandíbula/fisiologia , Fenômenos Mecânicos , Animais , Fenômenos Biomecânicos , Força de Mordida , Análise de Elementos Finitos , Modelos Biológicos , Comportamento Predatório
8.
BMC Evol Biol ; 12: 146, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22899809

RESUMO

BACKGROUND: The range of potential morphologies resulting from evolution is limited by complex interacting processes, ranging from development to function. Quantifying these interactions is important for understanding adaptation and convergent evolution. Using three-dimensional reconstructions of carnivoran and dasyuromorph tooth rows, we compared statistical models of the relationship between tooth row shape and the opposing tooth row, a static feature, as well as measures of mandibular motion during chewing (occlusion), which are kinetic features. This is a new approach to quantifying functional integration because we use measures of movement and displacement, such as the amount the mandible translates laterally during occlusion, as opposed to conventional morphological measures, such as mandible length and geometric landmarks. By sampling two distantly related groups of ecologically similar mammals, we study carnivorous mammals in general rather than a specific group of mammals. RESULTS: Statistical model comparisons demonstrate that the best performing models always include some measure of mandibular motion, indicating that functional and statistical models of tooth shape as purely a function of the opposing tooth row are too simple and that increased model complexity provides a better understanding of tooth form. The predictors of the best performing models always included the opposing tooth row shape and a relative linear measure of mandibular motion. CONCLUSIONS: Our results provide quantitative support of long-standing hypotheses of tooth row shape as being influenced by mandibular motion in addition to the opposing tooth row. Additionally, this study illustrates the utility and necessity of including kinetic features in analyses of morphological integration.


Assuntos
Carnívoros/anatomia & histologia , Modelos Biológicos , Dente/anatomia & histologia , Animais , Oclusão Dentária , Mandíbula/anatomia & histologia , Mandíbula/fisiologia , Marsupiais/anatomia & histologia , Mastigação
9.
Nature ; 483(7390): 457-60, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22419156

RESUMO

The Cretaceous-Paleogene mass extinction approximately 66 million years ago is conventionally thought to have been a turning point in mammalian evolution. Prior to that event and for the first two-thirds of their evolutionary history, mammals were mostly confined to roles as generalized, small-bodied, nocturnal insectivores, presumably under selection pressures from dinosaurs. Release from these pressures, by extinction of non-avian dinosaurs at the Cretaceous-Paleogene boundary, triggered ecological diversification of mammals. Although recent individual fossil discoveries have shown that some mammalian lineages diversified ecologically during the Mesozoic era, comprehensive ecological analyses of mammalian groups crossing the Cretaceous-Paleogene boundary are lacking. Such analyses are needed because diversification analyses of living taxa allow only indirect inferences of past ecosystems. Here we show that in arguably the most evolutionarily successful clade of Mesozoic mammals, the Multituberculata, an adaptive radiation began at least 20 million years before the extinction of non-avian dinosaurs and continued across the Cretaceous-Paleogene boundary. Disparity in dental complexity, which relates to the range of diets, rose sharply in step with generic richness and disparity in body size. Moreover, maximum dental complexity and body size demonstrate an adaptive shift towards increased herbivory. This dietary expansion tracked the ecological rise of angiosperms and suggests that the resources that were available to multituberculates were relatively unaffected by the Cretaceous-Paleogene mass extinction. Taken together, our results indicate that mammals were able to take advantage of new ecological opportunities in the Mesozoic and that at least some of these opportunities persisted through the Cretaceous-Paleogene mass extinction. Similar broad-scale ecomorphological inventories of other radiations may help to constrain the possible causes of mass extinctions.


Assuntos
Evolução Biológica , Dinossauros/fisiologia , Extinção Biológica , Mamíferos/fisiologia , Animais , Tamanho Corporal , Dieta/história , Dieta/veterinária , Fósseis , Herbivoria/fisiologia , História Antiga , Magnoliopsida/classificação , Magnoliopsida/fisiologia , Mamíferos/anatomia & histologia , Mamíferos/classificação , Filogenia , Fatores de Tempo , Dente/anatomia & histologia
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