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1.
Immunity ; 44(6): 1406-21, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27287410

RESUMO

Monobenzone is a pro-hapten that is exclusively metabolized by melanocytes, thereby haptenizing melanocyte-specific antigens, which results in cytotoxic autoimmunity specifically against pigmented cells. Studying monobenzone in a setting of contact hypersensitivity (CHS), we observed that monobenzone induced a long-lasting, melanocyte-specific immune response that was dependent on NK cells, yet fully intact in the absence of T- and B cells. Consistent with the concept of "memory NK cells," monobenzone-induced NK cells resided in the liver and transfer of these cells conferred melanocyte-specific immunity to naive animals. Monobenzone-exposed skin displayed macrophage infiltration and cutaneous lymph nodes showed an inflammasome-dependent influx of macrophages with a tissue-resident phenotype, coinciding with local NK cell activation. Indeed, macrophage depletion or the absence of the NLRP3 inflammasome, the adaptor protein ASC or interleukin-18 (IL-18) abolished monobenzone CHS, thereby establishing a non-redundant role for the NLRP3 inflammasome as a critical proinflammatory checkpoint in the induction of hapten-dependent memory NK cells.


Assuntos
Dermatite de Contato/imunologia , Memória Imunológica , Inflamassomos/imunologia , Células Matadoras Naturais/imunologia , Macrófagos/fisiologia , Melanócitos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Imunidade Adaptativa , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD , Células Cultivadas , Hidroquinonas , Interleucina-18/genética , Interleucina-18/metabolismo , Fígado/patologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética
2.
Int J Obes (Lond) ; 48(8): 1126-1132, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38734850

RESUMO

OBJECTIVE: To evaluate the association between maternal BMI and congenital heart defects (CHDs) in the offspring when including live births, stillbirths, aborted and terminated pregnancies and to investigate if maternal interpregnancy weight changes between the first and second pregnancy influences the risk of foetal CHDs. METHODS: A nationwide cohort study of all singleton pregnancies in Denmark from 2008 to 2018. Data were retrieved from the Danish Foetal Medicine Database, which included both pre- and postnatal diagnoses of CHDs. Children or foetuses with chromosomal aberrations were excluded. Odds ratios were calculated with logistic regression models for CHDs overall, severe CHDs and five of the most prevalent subtypes of CHDs. RESULTS: Of the 547 105 pregnancies included in the cohort, 5 442 had CHDs (1.0%). Risk of CHDs became gradually higher with higher maternal BMI; for BMI 25-29.9 kg/m2, adjusted odds ratio (aOR) 1.17 (95% CI 1.10-1.26), for BMI 30-34.9 kg/m2, aOR 1.21 (95% CI 1.09-1.33), for BMI 35-39.9 kg/m2, aOR 1.29 (95% CI 1.11-1.50) and for BMI ≥ 40 kg/m2, aOR 1.85 (95% CI 1.54-2.21). Data was adjusted for maternal age, smoking status and year of estimated due date. The same pattern was seen for the subgroup of severe CHDs. Among the atrioventricular septal defects (n = 231), an association with maternal BMI ≥ 30 kg/m2 was seen, OR 1.67 (95% CI 1.13-2.44). 109 654 women were identified with their first and second pregnancies in the cohort. Interpregnancy BMI change was associated with the risk of CHDs in the second pregnancy (BMI 2 to < 4 kg/m2: aOR 1.29, 95% CI 1.09-1.53; BMI ≥ 4 kg/m2: aOR 1.36, 95% CI 1.08-1.68). CONCLUSION: The risk of foetal CHDs became gradually higher with higher maternal BMI and interpregnancy weight increases above 2 BMI units were also associated with a higher risk of CHDs.


Assuntos
Cardiopatias Congênitas , Obesidade Materna , Humanos , Feminino , Gravidez , Obesidade Materna/epidemiologia , Obesidade Materna/complicações , Cardiopatias Congênitas/epidemiologia , Adulto , Dinamarca/epidemiologia , Estudos de Coortes , Índice de Massa Corporal , Fatores de Risco , Recém-Nascido
3.
J Therm Biol ; 124: 103957, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39213954

RESUMO

Wildlife space use is driven by three primary mechanisms, predator avoidance, foraging, and thermoregulation. The latter has largely been overlooked in wildlife research. Understanding how habitat use is influenced by thermoregulatory properties is a critical component to depicting species' ecology. Galliformes' (i.e., ground nesting birds with precocial young) ecology is predisposed to thermal extremes, where newly hatched chicks are unable to thermoregulate <14 d post-hatch, and have limited capabilities until >21 d post-hatch. We examined greater sage-grouse (Centrocercus urophasianus) brood rearing habitats and provide the first evaluation as to how microscale thermal environments influenced habitat selection. We monitored 24 broods, collected 82,929 black bulb temperature measurements from thermal arrays (n = 256) comprised of stainless steel black bulbs (i.e., surrogate for operative temperature) to compare brood morning (i.e., foraging, n = 78), afternoon (i.e., loafing, n = 82) and associated random locations (n = 96) between early (≤21 d post-hatch) and late (>21 d post-hatch) brood-rearing. We measured vegetation at all locations to disentangle relationships between cover and thermoregulatory metrics. We found that microclimates at all foraging locations heated more rapidly than either their loafing or random locations. Alternatively, loafing locations moderated ambient temperature more effectively than foraging locations but were similar to random locations. Broods were using loafing sites that both increased their ability to avoid predators (i.e., increased shrub structure) and buffered ambient temperature better than their foraging locations. Interestingly, random afternoon locations tended to lack concealment from predators, despite these locations showing improved thermal buffering compared to foraging locations. However, early brood-rearing habitats appeared to moderate ambient temperatures more effectively than late. Our results suggested that managing vegetation for structural heterogeneity will afford a diversity of thermal refuge for greater sage-grouse broods during this critical life history stage.


Assuntos
Ecossistema , Galliformes , Microclima , Animais , Galliformes/fisiologia , Regulação da Temperatura Corporal , Comportamento de Nidação , Temperatura
4.
Biometrics ; 79(4): 3941-3953, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37443410

RESUMO

Integrated models are a popular tool for analyzing species of conservation concern. Species of conservation concern are often monitored by multiple entities that generate several datasets. Individually, these datasets may be insufficient for guiding management due to low spatio-temporal resolution, biased sampling, or large observational uncertainty. Integrated models provide an approach for assimilating multiple datasets in a coherent framework that can compensate for these deficiencies. While conventional integrated models have been used to assimilate count data with surveys of survival, fecundity, and harvest, they can also assimilate ecological surveys that have differing spatio-temporal regions and observational uncertainties. Motivated by independent aerial and ground surveys of lesser prairie-chicken, we developed an integrated modeling approach that assimilates density estimates derived from surveys with distinct sources of observational error into a joint framework that provides shared inference on spatio-temporal trends. We model these data using a Bayesian Markov melding approach and apply several data augmentation strategies for efficient sampling. In a simulation study, we show that our integrated model improved predictive performance relative to models for analyzing the surveys independently. We use the integrated model to facilitate prediction of lesser prairie-chicken density at unsampled regions and perform a sensitivity analysis to quantify the inferential cost associated with reduced survey effort.


Assuntos
Animais Selvagens , Animais , Teorema de Bayes , Inquéritos e Questionários , Simulação por Computador , Incerteza
5.
Eur J Pediatr ; 181(3): 1175-1184, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34783897

RESUMO

Using provisional or opportunistic data, three nationwide studies (The Netherlands, the USA and Denmark) have identified a reduction in preterm or extremely preterm births during periods of COVID-19 restrictions. However, none of the studies accounted for perinatal deaths. To determine whether the reduction in extremely preterm births, observed in Denmark during the COVID-19 lockdown, could be the result of an increase in perinatal deaths and to assess the impact of extended COVID-19 restrictions, we performed a nationwide Danish register-based prevalence proportion study. We examined all singleton pregnancies delivered in Denmark during the COVID-19 strict lockdown calendar periods (March 12-April 14, 2015-2020, N = 31,164 births) and the extended calendar periods of COVID-19 restrictions (February 27-September 30, 2015-2020, N = 214,862 births). The extremely preterm birth rate was reduced (OR 0.27, 95% CI 0.07 to 0.86) during the strict lockdown period in 2020, while perinatal mortality was not significantly different. During the extended period of restrictions in 2020, the extremely preterm birth rate was marginally reduced, and a significant reduction in the stillbirth rate (OR 0.69, 0.50 to 0.95) was observed. No changes in early neonatal mortality rates were found.Conclusion: Stillbirth and extremely preterm birth rates were reduced in Denmark during the period of COVID-19 restrictions and lockdown, respectively, suggesting that aspects of these containment and control measures confer an element of protection. The present observational study does not allow for causal inference; however, the results support the design of studies to ascertain whether behavioural or social changes for pregnant women may improve pregnancy outcomes. What is Known: • The aetiologies of preterm birth and stillbirth are multifaceted and linked to a wide range of socio-demographic, medical, obstetric, foetal, psychosocial and environmental factors. • The COVID-19 lockdown saw a reduction in extremely preterm births in Denmark and other high-income countries. An urgent question is whether this reduction can be explained by increased perinatal mortality. What is New: • The reduction in extremely preterm births during the Danish COVID-19 lockdown was not a consequence of increased perinatal mortality, which remained unchanged during this period. • The stillbirth rate was reduced throughout the extended period of COVID-19 restrictions.


Assuntos
COVID-19 , Morte Perinatal , Nascimento Prematuro , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Dinamarca/epidemiologia , Feminino , Humanos , Mortalidade Infantil , Recém-Nascido , Gravidez , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , SARS-CoV-2 , Natimorto/epidemiologia
6.
Conserv Biol ; 35(5): 1564-1574, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33728682

RESUMO

Long-term population declines have elevated recovery of grassland avifauna to among the highest conservation priorities in North America. Because most of the Great Plains is privately owned, recovery of grassland bird populations depends on voluntary conservation with strong partnerships between private landowners and resource professionals. Despite large areas enrolled in voluntary practices through U.S. Department of Agriculture's Lesser Prairie-chicken (Tympanuchus pallidicinctus) Initiative (LPCI), the effectiveness of Farm Bill investments for meeting wildlife conservation goals remains an open question. Our objectives were to evaluate extents to which Conservation Reserve Program (CRP) and LPCI-grazing practices influence population densities of grassland birds; estimate relative contributions of practices to regional bird populations; and evaluate percentages of populations conserved relative to vulnerability of species. We designed a large-scale impact-reference study and used the Integrated Monitoring in Bird Conservation Regions program to evaluate bird population targets of the Playa Lakes Joint Venture. We used point transect distance sampling to estimate density and population size for 35 species of grassland birds on private lands enrolled in native or introduced CRP plantings and LPCI-prescribed grazing. Treatment effects indicated CRP plantings increased densities of three grassland obligates vulnerable to habitat loss, and LPCI grazing increased densities of four species requiring heterogeneity in dense, tall-grass structure (α = 0.1). Population estimates in 2016 indicated the practices conserved breeding habitat for 4.5 million birds (90% CI: 4.0-5.1), and increased population sizes of 16 species , totaling 1.8 million birds (CI: 1.4-2.4). Conservation practices on private land benefited the most vulnerable grassland obligate species (AICc weight = 0.53). By addressing habitat loss and degradation in agricultural landscapes, conservation on private land provides a solution to declining avifauna of North America and scales up to meet population recovery goals for the most imperiled grassland birds.


Ampliación de la Conservación en Terrenos Privados para Cumplir los Objetivos de Recuperación para Aves de Pastizales Resumen La declinación a largo plazo de las poblaciones ha posicionado a la recuperación de la avifauna de los pastizales entre las prioridades de conservación más importantes en América del Norte. Debido a que la mayor parte de las Grandes Planicies es propiedad privada, la recuperación de las poblaciones de aves de los pastizales depende de la conservación voluntaria sumada a la colaboración entre los terratenientes privados y los profesionales de la gestión de recursos. A pesar de que varias áreas se encuentran inscritas en prácticas voluntarias por medio de la Iniciativa de la Gallina de Pradera Menor (Tympanuchus pallidicinctus) (IGPM), la efectividad de la inversión del Proyecto de Ley de Granjas para cumplir con los objetivos de conservación de fauna todavía permanece como una pregunta abierta. Nuestros objetivos se enfocaron en evaluar hasta qué punto el Programa de Reservas de Conservación (PRC) y las prácticas de forrajeo de la IGPM influyen sobre la densidad poblacional de las aves de los pastizales; estimar las contribuciones relativas de las prácticas para las poblaciones de aves regionales; y evaluar el porcentaje de poblaciones conservadas en relación con la vulnerabilidad de la especie. Diseñamos un estudio a gran escala con referencia de impactos y usamos el programa de Monitoreo Integrado en las Regiones de Conservación de Aves para evaluar los objetivos poblacionales de las aves del Proyecto Conjunto de Playa Lakes. Usamos un muestreo de distancia por puntos en transecto para estimar la densidad y el tamaño poblacional de 35 especies de aves de pastizales en los terrenos privados inscritos en plantaciones nativas o introducidas del PRC y en las zonas de forrajeo prescritas por la IGPM. Los efectos del tratamiento indicaron que las plantaciones del PRC incrementaron la densidad de tres especies estrictas de pastizales vulnerables a la pérdida del hábitat, mientras que el forrajeo de la LPCI incrementó la densidad de cuatro especies que requieren heterogeneidad en la estructura de pastos altos y gruesos (α = 0.1). Las estimaciones poblacionales indicaron que las prácticas conservaron el hábitat de reproducción para 4.5 millones de aves (90% IC 4.0 - 5.1) e incrementaron el tamaño poblacional de 16 especies, para un total de 1.8 millones de aves (IC 1.4 - 2.4). Las prácticas de conservación en terrenos privados beneficiaron a las especies estrictas de pastizales más vulnerables (peso AICc = 0.53). Al abordar la pérdida y degradación del hábitat en los paisajes agrícolas, la conservación en terrenos privados proporciona una solución para la avifauna en declinación de América del Norte y se amplía para cumplir con los objetivos de recuperación establecidos para las aves de pastizales que se encuentran en mayor peligro.


Assuntos
Conservação dos Recursos Naturais , Pradaria , Animais , Aves , Objetivos , Melhoramento Vegetal
7.
Childs Nerv Syst ; 37(3): 819-830, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33226468

RESUMO

INTRODUCTION: Central nervous system (CNS) tumors constitute the most common form of solid neoplasms in children, but knowledge on genetic predisposition is sparse. In particular, whether susceptibility attributable to common variants is shared across CNS tumor types in children has not been investigated. The purpose of this study was to explore potential common genetic risk variants exhibiting pleiotropic effects across pediatric CNS tumors. We also investigated whether such susceptibility differs between early and late onset of disease. METHOD: A Danish nationwide genome-wide association study (GWAS) of 1,097 consecutive patients (< 15 years of age) with CNS tumors and a cohort of 4,745 population-based controls. RESULTS: For both the overall cohort and patients diagnosed after the age of four, the strongest association was rs12064625 which maps to PAPPA2 at 1q25.2 (p = 3.400 × 10-7 and 9.668 × 10-8, respectively). PAPPA2 regulates local bioavailability of insulin-like growth factor I (IGF-I). IGF-I is fundamental to CNS development and is involved in tumorigenesis across a wide range of different cancers. For the younger children, the strongest association was provided by rs11036373 mapping to LRRC4C at 11p12 (p = 7.620 × 10-7), which encoded protein acts as an axon guidance molecule during CNS development and has not formerly been associated with brain tumors. DISCUSSION: This GWAS indicates shared susceptibility attributable to common variants across pediatric CNS tumor types. Variations in genetic loci with roles in CNS development appear to be involved, possibly via altered IGF-I related pathways.


Assuntos
Neoplasias do Sistema Nervoso Central , Estudo de Associação Genômica Ampla , Neoplasias do Sistema Nervoso Central/genética , Criança , Loci Gênicos , Predisposição Genética para Doença/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , Proteína Plasmática A Associada à Gravidez
8.
J Therm Biol ; 95: 102791, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33454032

RESUMO

Temperature is increasingly recognized as an important component of wildlife habitat. Temperature is particularly important for avian nest sites, where extreme temperatures can influence adult behavior, embryonic development, and survival. For species inhabiting arid and semiarid climates, such as the scaled quail (Callipepla squamata), frequent exposure to extreme temperatures may increase the importance of the nest microclimate. Limited data suggest that scaled quail respond to temperature when selecting nest sites, and they are also known to respond to the presence of surface water and shrub cover on the landscape, two resources which may mitigate thermal stress. To better understand the role of temperature in nest site selection and survival, and to evaluate how other landscape resources may benefit nesting quail, we investigated nest site characteristics of scaled quail in southeastern New Mexico, USA. During the breeding seasons of 2018 and 2019 we located nests, monitored nest fate, and recorded thermal and vegetation characteristics at three spatial scales: the nest bowl, the nest microsite (area within 10 m of the nest bowl), and the landscape. We found that nest bowls moderated temperature relative to both the surrounding microsite and the broader landscape, remaining almost 5 °C cooler on average than the surrounding microsite at mid-day. Nest bowls also had taller, greater cover of vegetation compared to both the surrounding microsites and the landscape. Despite apparent selection for cooler temperatures and taller vegetation, these characteristics demonstrated a weak relationship with nest survival. Rather, nest survival was positively influenced by proximity to surface water and honey mesquite (Prosopis glandulosa), with survival decreasing with increasing distance from these features. Although the mechanism for this relationship is unclear, our results support the importance of temperature for nest site selection of ground-nesting birds in semiarid landscapes, and suggest further exploration of landscape-level sources of thermal mitigation.


Assuntos
Comportamento de Nidação , Codorniz/fisiologia , Termotolerância , Distribuição Animal , Animais , Ecossistema
9.
Appl Environ Microbiol ; 86(15)2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32444470

RESUMO

Anaerobic degradation of polycyclic aromatic hydrocarbons has been investigated mostly with naphthalene as a model compound. Naphthalene degradation by sulfate-reducing bacteria proceeds via carboxylation to 2-naphthoic acid, formation of a coenzyme A thioester, and subsequent reduction to 5,6,7,8-tetrahydro-2-naphthoyl-coenzyme A (THNCoA), which is further reduced to hexahydro-2-naphthoyl-CoA (HHNCoA) by tetrahydronaphthoyl-CoA reductase (THNCoA reductase), an enzyme similar to class I benzoyl-CoA reductases. When analyzing THNCoA reductase assays with crude cell extracts and NADH as electron donor via liquid chromatography-mass spectrometry (LC-MS), scanning for putative metabolites, we found that small amounts of the product of an HHNCoA hydratase were formed in the assays, but the downstream conversion by an NAD+-dependent ß-hydroxyacyl-CoA dehydrogenase was prevented by the excess of NADH in those assays. Experiments with alternative electron donors indicated that 2-oxoglutarate can serve as an indirect electron donor for the THNCoA-reducing system via a 2-oxoglutarate:ferredoxin oxidoreductase. With 2-oxoglutarate as electron donor, THNCoA was completely converted and further metabolites resulting from subsequent ß-oxidation-like reactions and hydrolytic ring cleavage were detected. These metabolites indicate a downstream pathway with water addition to HHNCoA and ring fission via a hydrolase acting on a ß'-hydroxy-ß-oxo-decahydro-2-naphthoyl-CoA intermediate. Formation of the downstream intermediate cis-2-carboxycyclohexylacetyl-CoA, which is the substrate for the previously described lower degradation pathway leading to the central metabolism, completes the anaerobic degradation pathway of naphthalene.IMPORTANCE Anaerobic degradation of polycyclic aromatic hydrocarbons is poorly investigated despite its significance in anoxic sediments. Using alternative electron donors for the 5,6,7,8-tetrahydro-2-naphthoyl-CoA reductase reaction, we observed intermediary metabolites of anaerobic naphthalene degradation via in vitro enzyme assays with cell extracts of anaerobic naphthalene degraders. The identified metabolites provide evidence that ring reduction terminates at the stage of hexahydro-2-naphthoyl-CoA and a sequence of ß-oxidation-like degradation reactions starts with a hydratase acting on this intermediate. The final product of this reaction sequence was identified as cis-2-carboxycyclohexylacetyl-CoA, a compound for which a further downstream degradation pathway has recently been published (P. Weyrauch, A. V. Zaytsev, S. Stephan, L. Kocks, et al., Environ Microbiol 19:2819-2830, 2017, https://doi.org/10.1111/1462-2920.13806). Our study reveals the first ring-cleaving reaction in the anaerobic naphthalene degradation pathway. It closes the gap between the reduction of the first ring of 2-naphthoyl-CoA by 2-napthoyl-CoA reductase and the lower degradation pathway starting from cis-2-carboxycyclohexylacetyl-CoA, where the second ring cleavage takes place.


Assuntos
Proteínas de Bactérias/metabolismo , Coenzima A/metabolismo , Deltaproteobacteria/enzimologia , Naftalenos/metabolismo , Oxirredutases/metabolismo , Anaerobiose , Oxirredução
10.
J Therm Biol ; 89: 102488, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32364967

RESUMO

Thermal heterogeneity provides options for organisms during extreme temperatures that can contribute to their fitness. Sagebrush (Artemisia spp.) communities exhibit vegetation heterogeneity that creates thermal variation at fine spatial scales. However, fire can change vegetation and thereby variation within the thermal environment of sagebrush communities. To describe spatial and temporal thermal variation of sagebrush communities following wildfire, we measured black bulb temperature (Tbb) at 144 random points dispersed within unburned and burned communities, for 24-h at each random point. We observed a wide thermal gradient in unburned (-7.3° to 63.3 °C) and burned (-4.6° to 64.8 °C) sagebrush communities. Moreover, unburned and burned sagebrush communities displayed high thermal heterogeneity relative to ambient temperature (Tair). Notably, Tbb varied by 47 °C in both unburned and burned communities when Tair was 20 °C. However, fire greatly reduced the buffering capacity and thermal refuge of Wyoming big sagebrush (A. tridentata wyomingensis) communities during low and high Tair. Furthermore, fire increased Tbb in Wyoming big sagebrush and mountain big sagebrush (A. t. vaseyana) during the mid-day hours. These results demonstrate how fire changes the thermal environment of big sagebrush communities and the importance of shrub structure which can provide thermal refuge for organisms in burned communities during extreme low and high Tair.


Assuntos
Artemisia/fisiologia , Termotolerância , Incêndios Florestais , Artemisia/genética , Ecossistema , Calor Extremo , Variação Genética
11.
Proc Natl Acad Sci U S A ; 113(45): 12745-12750, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27791084

RESUMO

Iconic sagebrush ecosystems of the American West are threatened by larger and more frequent wildfires that can kill sagebrush and facilitate invasion by annual grasses, creating a cycle that alters sagebrush ecosystem recovery post disturbance. Thwarting this accelerated grass-fire cycle is at the forefront of current national conservation efforts, yet its impacts on wildlife populations inhabiting these ecosystems have not been quantified rigorously. Within a Bayesian framework, we modeled 30 y of wildfire and climatic effects on population rates of change of a sagebrush-obligate species, the greater sage-grouse, across the Great Basin of western North America. Importantly, our modeling also accounted for variation in sagebrush recovery time post fire as determined by underlying soil properties that influence ecosystem resilience to disturbance and resistance to invasion. Our results demonstrate that the cumulative loss of sagebrush to direct and indirect effects of wildfire has contributed strongly to declining sage-grouse populations over the past 30 y at large spatial scales. Moreover, long-lasting effects from wildfire nullified pulses of sage-grouse population growth that typically follow years of higher precipitation. If wildfire trends continue unabated, model projections indicate sage-grouse populations will be reduced to 43% of their current numbers over the next three decades. Our results provide a timely example of how altered fire regimes are disrupting recovery of sagebrush ecosystems and leading to substantial declines of a widespread indicator species. Accordingly, we present scenario-based stochastic projections to inform conservation actions that may help offset the adverse effects of wildfire on sage-grouse and other wildlife populations.

12.
Scand J Clin Lab Invest ; 75(8): 699-709, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26403377

RESUMO

BACKGROUND: Congenital long QT syndrome (LQTS) is a hereditary cardiac channelopathy characterized by delayed ventricular repolarization, syncope, torsades de pointes and sudden cardiac death. Thirty-three members of five apparently 'unrelated' Danish families carry the KCNH2:c.87C> A; p.F29L founder mutation. METHODS AND RESULTS: Linkage disequilibrium mapping with microsatellites around KCNH2 enabled us to estimate the age of the founder mutation to be approximately 22 generations, corresponding to around 550 years. Neighbouring-Joining analysis disclosed one early and three later nodes. The median QTc time of the carriers was 490 ms (range: 415-589 ms) and no difference was seen between the different branches of the family. The mutation is malignant with a penetrance of 73%. Ten F29L carriers received implantable defibrillators (ICDs) (median age at implant 20 years), and of those four individuals experienced eight appropriate shocks. Patch-clamp analysis in HEK 293 cells, performed at 34°C disclosed a loss-of-function phenotype with fast deactivation, reduced steady-state inactivation current density and a positive voltage shift in inactivation. Western blotting of HEK 293 cells transfected with KCNH2:WT and KCNH2:c.87C> A revealed a reduced fraction of fully glycosylated hERG:p.F29L suggesting that this mutation results in defective trafficking. CONCLUSION: The altered channel gating kinetics in combination with defective trafficking of mutated channels is expected to result in reduced repolarizing current density and, thus, a LQTS phenotype.


Assuntos
Canais de Potássio Éter-A-Go-Go/genética , Síndrome do QT Longo/genética , Dinamarca , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go/fisiologia , Feminino , Efeito Fundador , Estudos de Associação Genética , Células HEK293 , Haplótipos , Humanos , Ativação do Canal Iônico , Cinética , Masculino , Potenciais da Membrana , Repetições de Microssatélites , Mutação de Sentido Incorreto , Fenótipo , Polimorfismo de Nucleotídeo Único , Transporte Proteico , Análise de Sequência de DNA
13.
Antimicrob Agents Chemother ; 58(6): 3468-74, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24709267

RESUMO

Nutritional supplementation to tuberculosis (TB) patients has been associated with increased weight and reduced mortality, but its effect on the pharmacokinetics of first-line anti-TB drugs is unknown. A cohort of 100 TB patients (58 men; median age, 35 [interquartile range {IQR}, 29 to 40] years, and median body mass index [BMI], 18.8 [17.3 to 19.9] kg/m(2)) were randomized to receive nutritional supplementation during the intensive phase of TB treatment. Rifampin plasma concentrations were determined after 1 week and 2 months of treatment. The effects of nutritional supplementation, HIV, time on treatment, body weight, and SLCO1B1 rs4149032 genotype were examined using a population pharmacokinetic model. The model adjusted for body size via allometric scaling, accounted for clearance autoinduction, and detected an increase in bioavailability (+14%) for the patients in the continuation phase. HIV coinfection in patients not receiving the supplementation was found to decrease bioavailability by 21.8%, with a median maximum concentration of drug in serum (Cmax) and area under the concentration-time curve from 0 to 24 h (AUC0-24) of 5.6 µg/ml and 28.6 µg · h/ml, respectively. HIV-coinfected patients on nutritional supplementation achieved higher Cmax and AUC0-24 values of 6.4 µg/ml and 31.6 µg · h/ml, respectively, and only 13.3% bioavailability reduction. No effect of the SLCO1B1 rs4149032 genotype was observed. In conclusion, nutritional supplementation during the first 2 months of TB treatment reduces the decrease in rifampin exposure observed in HIV-coinfected patients but does not affect exposure in HIV-uninfected patients. If confirmed in other studies, the use of defined nutritional supplementation in HIV-coinfected TB patients should be considered in TB control programs. (This study has the controlled trial registration number ISRCTN 16552219.).


Assuntos
Suplementos Nutricionais , Infecções por HIV/tratamento farmacológico , Rifampina/farmacocinética , Tuberculose/tratamento farmacológico , Adulto , Disponibilidade Biológica , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Estudos de Coortes , Coinfecção , Feminino , Genótipo , Infecções por HIV/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose/complicações , Aumento de Peso/efeitos dos fármacos
14.
PLoS One ; 18(4): e0272465, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37079505

RESUMO

INTRODUCTION: Pre-eclampsia (PE) is a leading cause of perinatal morbidity and mortality worldwide. Low-dose aspirin can prevent PE in high risk pregnancies if started early. However, despite intense research into the area, early pregnancy screening for PE risk is still not a routine part of pregnancy care. Several studies have described the application of artificial intelligence (AI) and machine learning (ML) in risk prediction of PE and its subtypes. A systematic review of available literature is necessary to catalogue the current applications of AI/ML methods in early pregnancy screening for PE, in order to better inform the development of clinically relevant risk prediction algorithms which will enable timely intervention and the development of new treatment strategies. The aim of this systematic review is to identify and assess studies regarding the application of AI/ML methods in early pregnancy screening for PE. METHODS: A systematic review of peer-reviewed as well as the pre-published cohort, case-control, or cross-sectional studies will be conducted. Relevant information will be accessed from the following databases; PubMed, Google Scholar, Scopus, Embase, Web of Science, Cochrane Library, Arxiv, BioRxiv, and MedRxiv. The studies will be evaluated by two reviewers in a parallel, blind assessment of the literature, a third reviewer will assess any studies in which the first two reviewers did not agree. The free online tool Rayyan, will be used in this literature assessment stage. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 checklist will be used to guide the review process and the methods of the studies will be assessed using the Newcastle-Ottawa scale. Narrative synthesis will be conducted for all included studies. Meta-analysis will also be conducted where data quality and availability allow. ETHICS AND DISSEMINATION: The review will not require ethical approval and the findings will be published in a peer-reviewed journal using the PRISMA guidelines. TRIAL REGISTRATION: Trial registration: The protocol for this systematic review has been registered in PROSPERO [CRD42022345786]. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022345786.


Assuntos
Pré-Eclâmpsia , Gravidez , Feminino , Humanos , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/prevenção & controle , Inteligência Artificial , Estudos Transversais , Aspirina , Projetos de Pesquisa , Aprendizado de Máquina , Revisões Sistemáticas como Assunto , Metanálise como Assunto
15.
J Invest Dermatol ; 143(7): 1197-1207.e3, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36584911

RESUMO

Actinic keratoses and cutaneous squamous cell carcinomas are associated with infections with human papillomavirus of genus beta (betaHPV) in immunosuppressed patients. To date, targeted therapy against betaHPV-associated skin cancer does not exist because of the large number of betaHPV without defined high-risk types. In this study, we hypothesized that the activation of innate antiviral immunity in the skin, asymptomatically infected with betaHPV, induces an antitumor response by in situ autovaccination and prevents the formation of betaHPV-associated skin cancer. To test this, we used the preclinical keratin-14-HPV8 transgenic mouse model, which develops skin tumors after mechanical wounding. Remarkably, treatment with the antiviral immune response activating polyinosinic-polycytidylic acid (poly[I:C]) completely prevented cutaneous tumor growth. The induction of the IFN-induced genes Cxcl10 and Ifit1 by poly(I:C) depended on MDA5 activation. Increased numbers of total and activated CD4 and CD8 T cells were detected in poly(I:C)-treated skin. T cells were found in the skin of poly(I:C)-treated mice but not in the skin tumors of untreated mice. T-cell depletion showed a predominant role of CD4 T cells in poly(I:C)-mediated tumor prevention. Our findings identify the MDA5 ligand poly(I:C) as a promising candidate for in situ autovaccination approaches, which might serve as a treatment strategy against betaHPV-related skin diseases.


Assuntos
Poli I-C , Neoplasias Cutâneas , Humanos , Camundongos , Animais , Camundongos Transgênicos , Neoplasias Cutâneas/genética , Pele , Antivirais/farmacologia
16.
Pregnancy Hypertens ; 34: 146-151, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37979242

RESUMO

OBJECTIVE: To determine whether mitochondrial haplogroups function as disease-modifiers or as susceptibility factors in preeclampsia using a traditional haplogroup association model. METHODS: This retrospective study haplotyped 235 control and 78 preeclamptic pregnancies from Denmark using either real-time PCR or Sanger sequencing depending on the rarity of the haplogroup. RESULTS: No significant association between haplogroups and the risk of preeclampsia was found, nor was any role for haplogroups in disease severity uncovered. CONCLUSION: Mitochondrial haplogroups are not associated with preeclampsia or the severity of preeclampsia in the Danish population. However, this study cannot exclude a role for less common mtDNA variation. Models that can examine these should be applied in preeclamptic patients.


Assuntos
Pré-Eclâmpsia , Feminino , Humanos , Estudos Retrospectivos , Pré-Eclâmpsia/genética , Mitocôndrias/genética , DNA Mitocondrial/genética , Haplótipos
17.
J Mol Cell Biol ; 15(1)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36626927

RESUMO

Radiotherapy induces DNA damage, resulting in cell-cycle arrest and activation of cell-intrinsic death pathways. However, the radioresistance of some tumour entities such as malignant melanoma limits its clinical application. The innate immune sensing receptor retinoic acid-inducible gene I (RIG-I) is ubiquitously expressed and upon activation triggers an immunogenic form of cell death in a variety of tumour cell types including melanoma. To date, the potential of RIG-I ligands to overcome radioresistance of tumour cells has not been investigated. Here, we demonstrate that RIG-I activation enhanced the extent and immunogenicity of irradiation-induced tumour cell death in human and murine melanoma cells in vitro and improved survival in the murine B16 melanoma model in vivo. Transcriptome analysis pointed to a central role for p53, which was confirmed using p53-/- B16 cells. In vivo, the additional effect of RIG-I in combination with irradiation on tumour growth was absent in mice carrying p53-/- B16 tumours, while the antitumoural response to RIG-I stimulation alone was maintained. Our results identify p53 as a pivotal checkpoint that is triggered by RIG-I resulting in enhanced irradiation-induced tumour cell death. Thus, the combined administration of RIG-I ligands and radiotherapy is a promising approach to treating radioresistant tumours with a functional p53 pathway, such as melanoma.


Assuntos
Melanoma Experimental , Proteína Supressora de Tumor p53 , Animais , Camundongos , Humanos , Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Ligantes , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Imunoterapia/métodos , Melanoma Maligno Cutâneo
18.
Genome Med ; 15(1): 17, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918911

RESUMO

BACKGROUND: Next-generation sequencing (NGS) based population screening holds great promise for disease prevention and earlier diagnosis, but the costs associated with screening millions of humans remain prohibitive. New methods for population genetic testing that lower the costs of NGS without compromising diagnostic power are needed. METHODS: We developed double batched sequencing where DNA samples are batch-sequenced twice - directly pinpointing individuals with rare variants. We sequenced batches of at-birth blood spot DNA using a commercial 113-gene panel in an explorative (n = 100) and a validation (n = 100) cohort of children who went on to develop pediatric cancers. All results were benchmarked against individual whole genome sequencing data. RESULTS: We demonstrated fully replicable detection of cancer-causing germline variants, with positive and negative predictive values of 100% (95% CI, 0.91-1.00 and 95% CI, 0.98-1.00, respectively). Pathogenic and clinically actionable variants were detected in RB1, TP53, BRCA2, APC, and 19 other genes. Analyses of larger batches indicated that our approach is highly scalable, yielding more than 95% cost reduction or less than 3 cents per gene screened for rare disease-causing mutations. We also show that double batched sequencing could cost-effectively prevent childhood cancer deaths through broad genomic testing. CONCLUSIONS: Our ultracheap genetic diagnostic method, which uses existing sequencing hardware and standard newborn blood spots, should readily open up opportunities for population-wide risk stratification using genetic screening across many fields of clinical genetics and genomics.


Assuntos
Predisposição Genética para Doença , Neoplasias , Criança , Recém-Nascido , Humanos , Testes Genéticos/métodos , Neoplasias/diagnóstico , Neoplasias/genética , Mutação em Linhagem Germinativa , Fatores de Risco , Sequenciamento de Nucleotídeos em Larga Escala , DNA
19.
Neuro Oncol ; 25(9): 1709-1720, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36810956

RESUMO

BACKGROUND: Although recent sequencing studies have revealed that 10% of childhood gliomas are caused by rare germline mutations, the role of common variants is undetermined and no genome-wide significant risk loci for pediatric central nervous system tumors have been identified to date. METHODS: Meta-analysis of 3 population-based genome-wide association studies comprising 4069 children with glioma and 8778 controls of multiple genetic ancestries. Replication was performed in a separate case-control cohort. Quantitative trait loci analyses and a transcriptome-wide association study were conducted to assess possible links with brain tissue expression across 18 628 genes. RESULTS: Common variants in CDKN2B-AS1 at 9p21.3 were significantly associated with astrocytoma, the most common subtype of glioma in children (rs573687, P-value of 6.974e-10, OR 1.273, 95% CI 1.179-1.374). The association was driven by low-grade astrocytoma (P-value of 3.815e-9) and exhibited unidirectional effects across all 6 genetic ancestries. For glioma overall, the association approached genome-wide significance (rs3731239, P-value of 5.411e-8), while no significant association was observed for high-grade tumors. Predicted decreased brain tissue expression of CDKN2B was significantly associated with astrocytoma (P-value of 8.090e-8). CONCLUSIONS: In this population-based genome-wide association study meta-analysis, we identify and replicate 9p21.3 (CDKN2B-AS1) as a risk locus for childhood astrocytoma, thereby establishing the first genome-wide significant evidence of common variant predisposition in pediatric neuro-oncology. We furthermore provide a functional basis for the association by showing a possible link to decreased brain tissue CDKN2B expression and substantiate that genetic susceptibility differs between low- and high-grade astrocytoma.


Assuntos
Astrocitoma , Glioma , RNA Longo não Codificante , Humanos , Criança , Estudo de Associação Genômica Ampla , Glioma/genética , Genótipo , Predisposição Genética para Doença , Astrocitoma/genética , Polimorfismo de Nucleotídeo Único
20.
Brain Commun ; 5(1): fcad004, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36694575

RESUMO

Hydrocephalus is one of the most common congenital disorders of the central nervous system and often displays psychiatric co-morbidities, in particular autism spectrum disorder. The disease mechanisms behind hydrocephalus are complex and not well understood, but some association with dysfunctional cilia in the brain ventricles and subarachnoid space has been indicated. A better understanding of the genetic aetiology of hydrocephalus, including the role of ciliopathies, may bring insights into a potentially shared genetic aetiology. In this population-based case-cohort study, we, for the first time, investigated variants of postulated hydrocephalus candidate genes. Using these data, we aimed to investigate potential involvement of the ciliome in hydrocephalus and describe genotype-phenotype associations with an autism spectrum disorder. One-hundred and twenty-one hydrocephalus candidate genes were screened in a whole-exome-sequenced sub-cohort of the Lundbeck Foundation Initiative for Integrative Psychiatric Research study, comprising 72 hydrocephalus patients and 4181 background population controls. Candidate genes containing high-impact variants of interest were systematically evaluated for their involvement in ciliary function and an autism spectrum disorder. The median age at diagnosis for the hydrocephalus patients was 0 years (range 0-27 years), the median age at analysis was 22 years (11-35 years), and 70.5% were males. The median age for controls was 18 years (range 11-26 years) and 53.3% were males. Fifty-two putative hydrocephalus-associated variants in 34 genes were identified in 42 patients (58.3%). In hydrocephalus cases, we found increased, but not significant, enrichment of high-impact protein altering variants (odds ratio 1.51, 95% confidence interval 0.92-2.51, P = 0.096), which was driven by a significant enrichment of rare protein truncating variants (odds ratio 2.71, 95% confidence interval 1.17-5.58, P = 0.011). Fourteen of the genes with high-impact variants are part of the ciliome, whereas another six genes affect cilia-dependent processes during neurogenesis. Furthermore, 15 of the 34 genes with high-impact variants and three of eight genes with protein truncating variants were associated with an autism spectrum disorder. Because symptoms of other diseases may be neglected or masked by the hydrocephalus-associated symptoms, we suggest that patients with congenital hydrocephalus undergo clinical genetic assessment with respect to ciliopathies and an autism spectrum disorder. Our results point to the significance of hydrocephalus as a ciliary disease in some cases. Future studies in brain ciliopathies may not only reveal new insights into hydrocephalus but also, brain disease in the broadest sense, given the essential role of cilia in neurodevelopment.

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