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1.
Nature ; 625(7996): 760-767, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38092039

RESUMO

GDF15, a hormone acting on the brainstem, has been implicated in the nausea and vomiting of pregnancy, including its most severe form, hyperemesis gravidarum (HG), but a full mechanistic understanding is lacking1-4. Here we report that fetal production of GDF15 and maternal sensitivity to it both contribute substantially to the risk of HG. We confirmed that higher GDF15 levels in maternal blood are associated with vomiting in pregnancy and HG. Using mass spectrometry to detect a naturally labelled GDF15 variant, we demonstrate that the vast majority of GDF15 in the maternal plasma is derived from the feto-placental unit. By studying carriers of rare and common genetic variants, we found that low levels of GDF15 in the non-pregnant state increase the risk of developing HG. Conversely, women with ß-thalassaemia, a condition in which GDF15 levels are chronically high5, report very low levels of nausea and vomiting of pregnancy. In mice, the acute food intake response to a bolus of GDF15 is influenced bi-directionally by prior levels of circulating GDF15 in a manner suggesting that this system is susceptible to desensitization. Our findings support a putative causal role for fetally derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by prepregnancy exposure to the hormone, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.


Assuntos
Fator 15 de Diferenciação de Crescimento , Hiperêmese Gravídica , Náusea , Vômito , Animais , Feminino , Humanos , Camundongos , Gravidez , Talassemia beta/sangue , Talassemia beta/metabolismo , Feto/metabolismo , Fator 15 de Diferenciação de Crescimento/sangue , Fator 15 de Diferenciação de Crescimento/metabolismo , Hormônios/sangue , Hormônios/metabolismo , Hiperêmese Gravídica/complicações , Hiperêmese Gravídica/metabolismo , Hiperêmese Gravídica/prevenção & controle , Hiperêmese Gravídica/terapia , Náusea/sangue , Náusea/complicações , Náusea/metabolismo , Placenta/metabolismo , Vômito/sangue , Vômito/complicações , Vômito/metabolismo
2.
Clin Exp Dermatol ; 47(4): 700-708, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34762763

RESUMO

BACKGROUND: Calciphylaxis is a life-threatening cutaneous ulcerative/necrotic disease characterized by vascular calcification/occlusion. It occurs most commonly in end-stage kidney disease (ESKD), known as uraemic calciphylaxis (UC) but can also occur in patients with chronic kidney disease (CKD) and normal kidney function (nonuraemic calciphylaxis; NUC). There are few large series of NUC in the literature. AIM: To compare the clinicopathological features of UC and NUC. METHODS: We retrospectively compared the clinicopathological features of 35 patients with NUC during the period 2010-2020 with those of 53 patients with UC (control group). Cases were classified as NUC in the absence of all of the following: ESKD, significant CKD (defined as serum creatinine > 3 mg/dL or creatinine clearance < 15 mL/min) and acute kidney injury requiring kidney replacement therapy or kidney transplantation. RESULTS: NUC represented 40% of the total cases, and there was a higher number of women (P < 0.01) and a higher median body mass index (P = 0.06) compared with the control UC group. Elevated parathyroid hormone was present in 44% of patients with NUC. Most of the tested patients were positive for lupus anticoagulants (56%). NUC biopsies showed a higher rate of extravascular calcium deposits (73% vs. 47%, P = 0.03). Dermal reactive vascular proliferation was the most common dermal change (32%). CONCLUSIONS: NUC is more common than previously reported and shows a higher predilection for obese postmenopausal women. Undiagnosed hyperparathyroidism shows a possible association with NUC. Lupus anticoagulants were positive in most patients. NUC biopsies are more likely than UC biopsies to display extravascular calcium deposition.


Assuntos
Calciofilaxia , Falência Renal Crônica , Insuficiência Renal Crônica , Calciofilaxia/diagnóstico , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Insuficiência Renal Crônica/complicações , Estudos Retrospectivos , Fatores de Risco
3.
Can J Anaesth ; 69(9): 1086-1098, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35996071

RESUMO

PURPOSE: Accurate risk reassessment after surgery is crucial for postoperative planning for monitoring and disposition. Existing postoperative mortality risk prediction models using preoperative features do not incorporate intraoperative hemodynamic derangements that may alter risk stratification. Intraoperative vital signs may provide an objective and readily available prognostic resource. Our primary objective was to derive and internally validate a logistic regression (LR) model by adding intraoperative features to established preoperative predictors to predict 30-day postoperative mortality. METHODS: Following Research Ethics Board approval, we analyzed a historical cohort that included patients aged ≥ 45 undergoing noncardiac surgery with an overnight stay at two tertiary hospitals (2013 to 2017). Features included intraoperative vital signs (blood pressure, heart rate, end-tidal carbon dioxide partial pressure, oxygen saturation, and temperature) by threshold and duration of exposure, as well as patient, surgical, and anesthetic factors. The cohort was divided temporally 75:25 into derivation and validation sets. We constructed a multivariable LR model with 30-day all-cause mortality as the outcome and evaluated performance metrics. RESULTS: There were 30,619 patients in the cohort (mean [standard deviation] age, 66 [11] yr; 50.2% female; 2.0% mortality). In the validation set, the primary LR model showed a c-statistic of 0.893 (99% confidence interval [CI], 0.853 to 0.927), a Nagelkerke R-squared of 0.269, a scaled Brier score of 0.082, and an area under precision-recall curve of 0.158 (baseline 0.017 for an uninformative model). The addition of intraoperative vital signs to preoperative factors minimally improved discrimination and calibration. CONCLUSION: We derived and internally validated a model that incorporated vital signs to improve risk stratification after surgery. Preoperative factors were strongly predictive of mortality risk, and intraoperative predictors only minimally improved discrimination. External and prospective validations are needed. STUDY REGISTRATION: www. CLINICALTRIALS: gov (NCT04014010); registered on 10 July 2019.


RéSUMé: OBJECTIF: Une réévaluation précise des risques après la chirurgie est cruciale pour la planification postopératoire du monitorage et du congé. Les modèles existants de prédiction du risque de mortalité postopératoire utilisant des caractéristiques préopératoires n'intègrent pas les perturbations hémodynamiques peropératoires, lesquelles pourraient modifier la stratification du risque. Les signes vitaux peropératoires peuvent fournir une ressource pronostique objective et facilement disponible. Notre objectif principal était de dériver et de valider en interne un modèle de régression logistique (RL) en ajoutant des caractéristiques peropératoires aux prédicteurs préopératoires établis pour prédire la mortalité postopératoire à 30 jours. MéTHODE: À la suite de l'approbation du Comité d'éthique de la recherche, nous avons analysé une cohorte historique qui comprenait des patients âgés de ≥ 45 ans bénéficiant d'une chirurgie non cardiaque avec un séjour d'une nuit dans deux hôpitaux tertiaires (2013 à 2017). Les caractéristiques comprenaient les signes vitaux peropératoires (tension artérielle, fréquence cardiaque, pression télé-expiratoire en CO2, saturation en oxygène et température) par seuil et durée d'exposition, ainsi que des facteurs propres au patient, chirurgicaux et anesthésiques. La cohorte a été divisée temporellement 75:25 en ensembles de dérivation et de validation. Nous avons élaboré un modèle de RL multivariée avec la mortalité toutes causes confondues à 30 jours comme critère, et évalué les mesures de performance. RéSULTATS: Il y avait 30 619 patients dans la cohorte (âge moyen [écart type], 66 [11] ans; 50,2 % de femmes; 2,0 % de mortalité). Dans l'ensemble de validation, le modèle de RL primaire a montré une statistique c de 0,893 (intervalle de confiance [IC] à 99 %, 0,853 à 0,927), un R carré de Nagelkerke de 0,269, un score de Brier mis à l'échelle de 0,082 et une aire sous la courbe de rappel et précision de 0,158 (ligne de base 0,017 pour un modèle non informatif). L'ajout de signes vitaux peropératoires aux facteurs préopératoires a amélioré de façon minimale la discrimination et l'étalonnage. CONCLUSION: Nous avons dérivé et validé en interne un modèle qui incorporait des signes vitaux pour améliorer la stratification des risques après la chirurgie. Les facteurs préopératoires étaient fortement prédictifs du risque de mortalité, et les prédicteurs peropératoires n'ont que que très peu amélioré la discrimination. Une validation externe et prospective est nécessaire. ENREGISTREMENT DE L'éTUDE: www.ClinicalTrials.gov (NCT04014010); enregistrée le 10 juillet 2019.


Assuntos
Sinais Vitais , Idoso , Estudos de Coortes , Feminino , Humanos , Modelos Logísticos , Masculino , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
4.
J Environ Manage ; 304: 114112, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34923419

RESUMO

Seaweeds form the second largest global aquaculture product in volume, and despite rapid growth of the sector over the last 25 years, production and quality in top producing regions is becoming increasingly limited due to disease and pest outbreaks, the spread of non-native cultivars and the degradation of genetic health due to inbreeding. Most notably, the lack of biosecurity measures leading to disease and pest outbreaks are reported to cause the most significant production losses in the seaweed industry. This study uses the Knowledge, Attitude and Practice (KAP) survey tool to quantify and compare biosecurity cross-culturally, in two major red seaweed producing countries, the Philippines and Tanzania. Both countries have significantly different political contexts and the seaweed sector sits within two very different value chains. Seaweed-based commodities from these countries, however, enters the same international market for carrageenan, a thickening agent used for a variety of products globally. This study uses the KAP survey tool to assess currently-adopted biosecurity control measures and understand how potential policy strategies could be developed on an international scale. Farmers from both producing countries have good biosecurity knowledge. In Tanzania 64% farmers scored Fair or Good, and in the Philippines this was 95%. Corresponding scores in practices were lower, 85% Poor for Tanzania, and 88% Fair for the Philippines, indicating there is a lack of resources for farmers to implement additional practices. The information gathered using the KAP tool in the context of the global seaweed industry can be used to facilitate compromise between science, policy and practice whilst taking into consideration smaller-scale regional challenges. Given the results from the seaweed industry were similar to that of smallholder agricultural sectors, it is suggested that governmental programs to incentivise biosecurity in smallholder rural agriculture could be adapted for the seaweed industry. This study also demonstrates the potential use of the KAP survey, as a tool to accurately compare biosecurity challenges faced by farmers in different aquaculture sectors globally, and to encourage alignment in international approaches to aquaculture biosecurity policies.


Assuntos
Criação de Animais Domésticos , Alga Marinha , Aquicultura , Biosseguridade , Fazendeiros , Humanos
5.
Ethn Health ; 26(5): 769-785, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-30458623

RESUMO

Objectives: The dietary patterns of Pacific Islander Americans are partially influenced by a rich cultural heritage. There is little known about how cultural affinity affects the dietary choices of this small, but quickly growing population. This analysis attempts to understand how the association of cultural affinity on island foods consumption (IFC) varies by key demographic characteristics.Design: A sample of 240 Samoan and Tongan adults in California from the Pacific Islander Health Study (PIHS) was used. Psychometric properties of a novel 11-item cultural affinity scale were assessed. Univariate and bivariate analyses of the cultural affinity scale were completed to understand the distribution of cultural affinity score. Separate multivariable Poisson regression was used to assess the effect of interactions between cultural affinity and five key demographic factors on IFC.Results: Psychometric analysis of the PIHS cultural affinity scale revealed two unique factors. Significant interactions were found between cultural affinity and ethnicity and birthplace: the association between cultural affinity and IFC was larger among Samoans compared to Tongans and Samoan or Tongan birthplace was found to have a weaker association between cultural affinity and IFC. Interactions between cultural affinity and age, financial insecurity, and educational attainment were not significant.Conclusion: Understanding how cultural affinity varies in its effect on IFC is a part of understanding overall dietary patterns in this population.


Assuntos
Dieta , Havaiano Nativo ou Outro Ilhéu do Pacífico , Adulto , Etnicidade , Humanos
6.
Am J Public Health ; 110(9): 1332, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32673108

RESUMO

Objectives. To describe county-level socioeconomic profiles associated with Kentucky's 2017-2018 hepatitis A outbreak that predominately affected communities affected by the opioid epidemic.Methods. We linked county-level characteristics on socioeconomic and housing variables to counties' hepatitis A rates. Principal component analysis identified county profiles of poverty, education, disability, income inequality, grandparent responsibility, residential instability, and marital status. We used Poisson regression to estimate adjusted relative risks (RRs) and 95% confidence intervals (CIs).Results. Counties with scores reflecting an extremely disadvantaged profile (RR = 1.21; 95% CI = 0.99, 1.48) and greater percentage of nonmarried men, residential instability, and income inequality (RR = 1.15; 95% CI = 0.94, 1.41) had higher hepatitis A rates. Counties with scores reflecting more married adults, residential stability, and lower income inequality despite disability, poverty, and low education (RR = 0.77; 95% CI = 0.59, 1.00) had lower hepatitis A rates. Counties with a higher percentage of workers in the manufacturing industry had slightly lower rates (RR = 0.97; 95% CI = 0.94, 1.00).Conclusions. As expected, impoverished counties had higher hepatitis A rates. Evaluation across the socioeconomic patterns highlighted community-level factors (e.g., residential instability, income inequality, and social structures) that can be collected to augment hepatitis A data surveillance and used to identify higher-risk communities for targeted immunizations.


Assuntos
Hepatite A/epidemiologia , Epidemia de Opioides , Fatores Socioeconômicos , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Habitação/estatística & dados numéricos , Humanos , Kentucky/epidemiologia , Masculino
7.
Ethn Health ; 25(2): 305-321, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-29284279

RESUMO

Objectives: Pacific Islander Americans are a small, but quickly growing population that experiences alarming disparities in obesity and obesity-related chronic illnesses influenced by dietary patterns. This population also has a unique culinary heritage including traditional foods and more contemporary imports such as tinned meats and refined carbohydrates. This analysis is a novel attempt to understand the sociodemographic factors influencing island foods consumption.Design: A sample of 240 Samoan and Tongan adults in California from the Pacific Islander Health Study was used. Following univariate and bivariate analyses, a series of four multivariable regression models were created to predict past week frequency of island foods consumption after sequential adjustment for demographic, socioeconomic, and cultural covariates.Results: Participants reported consuming island foods an average of 2.93 times in the previous week, with the largest proportion of participants (20.42%) reporting eating island foods 6 or more times. Age and Samoan ethnicity were initially significant, positive predictors of island foods consumption, but their effect was attenuated after addition of cultural covariates. With the third model that adjusted for birthplace, financial insecurity and Tongan birthplace were positive predictors. Both lost significance in the fourth and final model upon addition of cultural affinity, which was positively associated with island foods.Conclusion: Understanding how sociodemographic factors are associated with island foods consumption is a first step in understanding the broad way in which an ethnically specific dietary pattern may be associated with obesity-related chronic illness risk among Pacific Islander Americans.


Assuntos
Dieta/etnologia , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Obesidade/etnologia , Fatores Socioeconômicos , Adulto , California , Comportamento Alimentar/psicologia , Feminino , Humanos , Masculino , Projetos Piloto , Samoa/etnologia , Tonga/etnologia
8.
Phys Rev Lett ; 121(5): 053001, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30118286

RESUMO

We report spectroscopic results on the 2s2p^{1}P_{1} state in neutral atomic beryllium-9. The absolute frequency for the center of gravity is determined to be 42 565.4501(13) cm^{-1}, a factor of 130 more precise than the previous experimental measurement. The result is in agreement with and a factor of 8 more precise than the current best theoretical estimate of 42 565.441(11) cm^{-1}, which was calculated including the effects of quantum electrodynamics. Because of the large natural linewidth of the transition, the hyperfine constants were not able to be extracted to high precision.

9.
Scand J Immunol ; 86(3): 143-155, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28671713

RESUMO

The complement and neutrophil defence systems, as major components of innate immunity, are activated during inflammation and infection. For neutrophil migration to the inflamed region, we hypothesized that the complement activation product C5a induces significant changes in cellular morphology before chemotaxis. Exposure of human neutrophils to C5a dose- and time-dependently resulted in a rapid C5a receptor-1 (C5aR1)-dependent shape change, indicated by enhanced flow cytometric forward-scatter area values. Similar changes were observed after incubation with zymosan-activated serum and in blood neutrophils during murine sepsis, but not in mice lacking the C5aR1. In human neutrophils, Amnis high-resolution digital imaging revealed a C5a-induced decrease in circularity and increase in the cellular length/width ratio. Biomechanically, microfluidic optical stretching experiments indicated significantly increased neutrophil deformability early after C5a stimulation. The C5a-induced shape changes were inhibited by pharmacological blockade of either the Cl-/HCO3--exchanger or the Cl- -channel. Furthermore, actin polymerization assays revealed that C5a exposure resulted in a significant polarization of the neutrophils. The functional polarization process triggered by ATP-P2X/Y-purinoceptor interaction was also involved in the C5a-induced shape changes, because pretreatment with suramin blocked not only the shape changes but also the subsequent C5a-dependent chemotactic activity. In conclusion, the data suggest that the anaphylatoxin C5a regulates basic neutrophil cell processes by increasing the membrane elasticity and cell size as a consequence of actin-cytoskeleton polymerization and reorganization, transforming the neutrophil into a migratory cell able to invade the inflammatory site and subsequently clear pathogens and molecular debris.


Assuntos
Citoesqueleto de Actina/imunologia , Forma Celular/imunologia , Complemento C5a/metabolismo , Inflamação/imunologia , Neutrófilos/imunologia , Actinas/metabolismo , Trifosfato de Adenosina/metabolismo , Células Cultivadas , Quimiotaxia , Antiportadores de Cloreto-Bicarbonato/metabolismo , Complemento C5a/imunologia , Humanos , Ativação de Neutrófilo , Neutrófilos/patologia , Receptor da Anafilatoxina C5a/metabolismo , Receptores Purinérgicos P2X/metabolismo , Transdução de Sinais
10.
Geophys Res Lett ; 44(10): 5104-5112, 2017 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29950746

RESUMO

Volcanic eruptions have global climate impacts, but their effect on the hydrologic cycle is poorly understood. We use a modified version of superposed epoch analysis, an eruption year list collated from multiple datasets, and seasonal paleoclimate reconstructions (soil moisture, precipitation, geopotential heights, and temperature) to investigate volcanic forcing of spring and summer hydroclimate over Europe and the Mediterranean over the last millennium. In the western Mediterranean, wet conditions occur in the eruption year and the following 3 years. Conversely, northwestern Europe and the British Isles experience dry conditions in response to volcanic eruptions, with the largest moisture deficits in post-eruption years 2 and 3. The precipitation response occurs primarily in late spring and early summer (April-July), a pattern that strongly resembles the negative phase of the East Atlantic Pattern. Modulated by this mode of climate variability, eruptions force significant, widespread, and heterogeneous hydroclimate responses across Europe and the Mediterranean.

11.
Trop Anim Health Prod ; 49(2): 409-416, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28054227

RESUMO

Eimeriosis is caused by a protozoan infection affecting most domestic animal species. Outbreaks in cattle are associated with various environmental factors in temperate climates but limited work has been done in tropical settings. The objective of this work was to determine the prevalence and environmental factors associated with bovine Eimeria spp. infection in a mixed farming area of western Kenya. A total of 983 cattle were sampled from 226 cattle-keeping households. Faecal samples were collected directly from the rectum via digital extraction and analysed for the presence of Eimeria spp. infection using the MacMaster technique. Individual and household level predictors of infection were explored using mixed effects logistic regression. The prevalence of individual animal Eimeria infection was 32.8% (95% CI 29.9-35.9). A positive linear relationship was found between risk of Eimeria infection and increasing temperature (OR = 1.4, 95% CI 1.06-1.86) and distance to areas at risk of flooding (OR = 1.49, 95% CI 1.17-1.91). There was weak evidence of non-linear relationship between Eimeria infection and the proportion of the area around a household that was classified as swamp (OR = 1.12, 95% CI 0.87-1.44; OR (quadratic term) = 0.85, 95% CI 0.73-1.00), and the sand content of the soil (OR = 1.18, 95% CI 0.91-1.53; OR (quadratic term) = 1.1, 95% CI 0.99-1.23). The risk of animal Eimeria spp. infection is influenced by a number of climatic and soil-associated conditions.


Assuntos
Doenças dos Bovinos/epidemiologia , Bovinos/parasitologia , Coccidiose/veterinária , Eimeria/isolamento & purificação , Animais , Doenças dos Bovinos/parasitologia , Análise por Conglomerados , Coccidiose/epidemiologia , Meio Ambiente , Fezes , Geografia , Quênia/epidemiologia , Prevalência , Análise de Regressão , Risco , Solo
13.
Mol Psychiatry ; 20(11): 1366-72, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25421404

RESUMO

Significant evidence exists for the association between copy number variants (CNVs) and Autism Spectrum Disorder (ASD); however, most of this work has focused solely on the diagnosis of ASD. There is limited understanding of the impact of CNVs on the 'sub-phenotypes' of ASD. The objective of this paper is to evaluate associations between CNVs in differentially brain expressed (DBE) genes or genes previously implicated in ASD/intellectual disability (ASD/ID) and specific sub-phenotypes of ASD. The sample consisted of 1590 cases of European ancestry from the Autism Genome Project (AGP) with a diagnosis of an ASD and at least one rare CNV impacting any gene and a core set of phenotypic measures, including symptom severity, language impairments, seizures, gait disturbances, intelligence quotient (IQ) and adaptive function, as well as paternal and maternal age. Classification analyses using a non-parametric recursive partitioning method (random forests) were employed to define sets of phenotypic characteristics that best classify the CNV-defined groups. There was substantial variation in the classification accuracy of the two sets of genes. The best variables for classification were verbal IQ for the ASD/ID genes, paternal age at birth for the DBE genes and adaptive function for de novo CNVs. CNVs in the ASD/ID list were primarily associated with communication and language domains, whereas CNVs in DBE genes were related to broader manifestations of adaptive function. To our knowledge, this is the first study to examine the associations between sub-phenotypes and CNVs genome-wide in ASD. This work highlights the importance of examining the diverse sub-phenotypic manifestations of CNVs in ASD, including the specific features, comorbid conditions and clinical correlates of ASD that comprise underlying characteristics of the disorder.


Assuntos
Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/fisiopatologia , Variações do Número de Cópias de DNA/genética , Predisposição Genética para Doença/genética , Fenótipo , Adolescente , Adulto , Idoso , Análise de Variância , Crianças com Deficiência , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pais , Escalas de Graduação Psiquiátrica , Adulto Jovem
14.
Geophys Res Lett ; 43(18): 9886-9894, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-29780186

RESUMO

Multidecadal droughts that occurred during the Medieval Climate Anomaly represent an important target for validating the ability of climate models to adequately characterize drought risk over the near-term future. A prominent hypothesis is that these megadroughts were driven by a centuries-long radiatively forced shift in the mean state of the tropical Pacific Ocean. Here we use a novel combination of spatiotemporal tree-ring reconstructions of Northern Hemisphere hydroclimate to infer the atmosphere-ocean dynamics that coincide with megadroughts over the American West, and find that these features are consistently associated with ten-to-thirty year periods of frequent cold El Niño Southern Oscillation conditions and not a centuries-long shift in the mean of the tropical Pacific Ocean. These results suggest an important role for internal variability in driving past megadroughts. State-of-the art climate models from the Coupled Model Intercomparison Project phase 5, however, do not simulate a consistent association between megadroughts and internal variability of the tropical Pacific Ocean, with implications for our confidence in megadrought risk projections.

15.
BMC Vet Res ; 12(1): 192, 2016 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-27608711

RESUMO

BACKGROUND: African swine fever (ASF), caused by African swine fever virus (ASFV), is a severe haemorrhagic disease of pigs, outbreaks of which can have a devastating impact upon commercial and small-holder pig production. Pig production in western Kenya is characterised by low-input, free-range systems practised by poor farmers keeping between two and ten pigs. These farmers are particularly vulnerable to the catastrophic loss of livestock assets experienced in an ASF outbreak. This study wished to expand our understanding of ASFV epidemiology during a period when no outbreaks were reported. RESULTS: Two hundred and seventy six whole blood samples were analysed using two independent conventional and real time PCR assays to detect ASFV. Despite no recorded outbreak of clinical ASF during this time, virus was detected in 90/277 samples analysed by conventional PCR and 142/209 samples analysed by qPCR. Genotyping of a sub-set of these samples indicated that the viruses associated with the positive samples were classified within genotype IX and that these strains were therefore genetically similar to the virus associated with the 2006/2007 ASF outbreaks in Kenya. CONCLUSION: The detection of ASFV viral DNA in a relatively high number of pigs delivered for slaughter during a period with no reported outbreaks provides support for two hypotheses, which are not mutually exclusive: (1) that virus prevalence may be over-estimated by slaughter-slab sampling, relative to that prevailing in the wider pig population; (2) that sub-clinical, chronically infected or recovered pigs may be responsible for persistence of the virus in endemic areas.


Assuntos
Vírus da Febre Suína Africana/isolamento & purificação , Febre Suína Africana/virologia , Febre Suína Africana/sangue , Febre Suína Africana/epidemiologia , Animais , Surtos de Doenças/veterinária , Genótipo , Quênia/epidemiologia , Suínos
16.
Aging Ment Health ; 20(7): 676-99, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26078084

RESUMO

OBJECTIVE: Little is known about how and to what extent people with dementia live positively with their condition. This study aimed to review and carry out a synthesis of qualitative studies where accounts of the subjective experiences of people with dementia contained evidence of positive states, experiences or attributes. METHODS: A meta-synthesis was undertaken to generate an integrated and interpretive account of the ability of people with dementia to have positive experiences. A methodological quality assessment was undertaken to maximize the reliability and validity of this synthesis and to contextualize the findings with regard to methodological constraints and epistemological concepts. FINDINGS: Twenty-seven papers were included. Three super-ordinate themes relating to positive experiences and attributes were identified, each with varying and complementing sub-themes. The first super-ordinate theme related to the experience of engaging with life in ageing rather than explicitly to living with dementia. The second theme related to engaging with dementia itself and comprised the strengths that people can utilize in facing and fighting the condition. The third theme captured how people with dementia might transcend the condition and seek ways to maintain identity and even achieve personal growth. CONCLUSIONS: This review provides a first step towards understanding what conceptual domains might be important in defining positive outcomes for people who live with dementia. Highlighting the potential for people to have positive experiences in spite of or even because of their dementia has important implications for de-stigmatizing dementia and will enhance person-centred approaches to care.


Assuntos
Atividades Cotidianas , Envelhecimento , Demência/psicologia , Qualidade de Vida , Adaptação Psicológica , Humanos , Apoio Social
18.
Circulation ; 130(6): 484-95, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25092278

RESUMO

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden death in the young, although not all patients eligible for sudden death prevention with an implantable cardioverter-defibrillator are identified. Contrast-enhanced cardiovascular magnetic resonance with late gadolinium enhancement (LGE) has emerged as an in vivo marker of myocardial fibrosis, although its role in stratifying sudden death risk in subgroups of HCM patients remains incompletely understood. METHODS AND RESULTS: We assessed the relation between LGE and cardiovascular outcomes in 1293 HCM patients referred for cardiovascular magnetic resonance and followed up for a median of 3.3 years. Sudden cardiac death (SCD) events (including appropriate defibrillator interventions) occurred in 37 patients (3%). A continuous relationship was evident between LGE by percent left ventricular mass and SCD event risk in HCM patients (P=0.001). Extent of LGE was associated with an increased risk of SCD events (adjusted hazard ratio, 1.46/10% increase in LGE; P=0.002), even after adjustment for other relevant disease variables. LGE of ≥15% of LV mass demonstrated a 2-fold increase in SCD event risk in those patients otherwise considered to be at lower risk, with an estimated likelihood for SCD events of 6% at 5 years. Performance of the SCD event risk model was enhanced by LGE (net reclassification index, 12.9%; 95% confidence interval, 0.3-38.3). Absence of LGE was associated with lower risk for SCD events (adjusted hazard ratio, 0.39; P=0.02). Extent of LGE also predicted the development of end-stage HCM with systolic dysfunction (adjusted hazard ratio, 1.80/10% increase in LGE; P<0.03). CONCLUSIONS: Extensive LGE measured by quantitative contrast enhanced CMR provides additional information for assessing SCD event risk among HCM patients, particularly patients otherwise judged to be at low risk.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/mortalidade , Meios de Contraste , Morte Súbita Cardíaca/epidemiologia , Gadolínio , Imagem Cinética por Ressonância Magnética/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Método Simples-Cego , Adulto Jovem
19.
Tissue Antigens ; 86(3): 216-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26206472

RESUMO

Three novel HLA-DQB1 alleles were found after sequence-based typing of 3558 random UK European routine blood donors.


Assuntos
Alelos , Cadeias beta de HLA-DQ/genética , Humanos
20.
Mol Psychiatry ; 18(12): 1315-23, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23979605

RESUMO

De novo genetic variation is an important class of risk factors for autism spectrum disorder (ASD). Recently, whole-exome sequencing of ASD families has identified a novel de novo missense mutation in the human dopamine (DA) transporter (hDAT) gene, which results in a Thr to Met substitution at site 356 (hDAT T356M). The dopamine transporter (DAT) is a presynaptic membrane protein that regulates dopaminergic tone in the central nervous system by mediating the high-affinity reuptake of synaptically released DA, making it a crucial regulator of DA homeostasis. Here, we report the first functional, structural and behavioral characterization of an ASD-associated de novo mutation in the hDAT. We demonstrate that the hDAT T356M displays anomalous function, characterized as a persistent reverse transport of DA (substrate efflux). Importantly, in the bacterial homolog leucine transporter, substitution of A289 (the homologous site to T356) with a Met promotes an outward-facing conformation upon substrate binding. In the substrate-bound state, an outward-facing transporter conformation is required for substrate efflux. In Drosophila melanogaster, the expression of hDAT T356M in DA neurons-lacking Drosophila DAT leads to hyperlocomotion, a trait associated with DA dysfunction and ASD. Taken together, our findings demonstrate that alterations in DA homeostasis, mediated by aberrant DAT function, may confer risk for ASD and related neuropsychiatric conditions.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Dopamina/fisiologia , Animais , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Pré-Escolar , Neurônios Dopaminérgicos/fisiologia , Drosophila melanogaster/genética , Homeostase/genética , Humanos , Masculino , Atividade Motora/genética , Mutação de Sentido Incorreto/genética , Fatores de Risco
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