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1.
Nature ; 628(8007): 355-358, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38030722

RESUMO

Sustainable agriculture requires balancing crop yields with the effects of pesticides on non-target organisms, such as bees and other crop pollinators. Field studies demonstrated that agricultural use of neonicotinoid insecticides can negatively affect wild bee species1,2, leading to restrictions on these compounds3. However, besides neonicotinoids, field-based evidence of the effects of landscape pesticide exposure on wild bees is lacking. Bees encounter many pesticides in agricultural landscapes4-9 and the effects of this landscape exposure on colony growth and development of any bee species remains unknown. Here we show that the many pesticides found in bumble bee-collected pollen are associated with reduced colony performance during crop bloom, especially in simplified landscapes with intensive agricultural practices. Our results from 316 Bombus terrestris colonies at 106 agricultural sites across eight European countries confirm that the regulatory system fails to sufficiently prevent pesticide-related impacts on non-target organisms, even for a eusocial pollinator species in which colony size may buffer against such impacts10,11. These findings support the need for postapproval monitoring of both pesticide exposure and effects to confirm that the regulatory process is sufficiently protective in limiting the collateral environmental damage of agricultural pesticide use.


Assuntos
Inseticidas , Praguicidas , Abelhas , Animais , Praguicidas/toxicidade , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Agricultura , Pólen
2.
Nature ; 596(7872): 389-392, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34349259

RESUMO

Global concern over widely documented declines in pollinators1-3 has led to the identification of anthropogenic stressors that, individually, are detrimental to bee populations4-7. Synergistic interactions between these stressors could substantially amplify the environmental effect of these stressors and could therefore have important implications for policy decisions that aim to improve the health of pollinators3,8,9. Here, to quantitatively assess the scale of this threat, we conducted a meta-analysis of 356 interaction effect sizes from 90 studies in which bees were exposed to combinations of agrochemicals, nutritional stressors and/or parasites. We found an overall synergistic effect between multiple stressors on bee mortality. Subgroup analysis of bee mortality revealed strong evidence for synergy when bees were exposed to multiple agrochemicals at field-realistic levels, but interactions were not greater than additive expectations when bees were exposed to parasites and/or nutritional stressors. All interactive effects on proxies of fitness, behaviour, parasite load and immune responses were either additive or antagonistic; therefore, the potential mechanisms that drive the observed synergistic interactions for bee mortality remain unclear. Environmental risk assessment schemes that assume additive effects of the risk of agrochemical exposure may underestimate the interactive effect of anthropogenic stressors on bee mortality and will fail to protect the pollinators that provide a key ecosystem service that underpins sustainable agriculture.


Assuntos
Agroquímicos/efeitos adversos , Agroquímicos/intoxicação , Abelhas/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Agricultura , Fenômenos Fisiológicos da Nutrição Animal , Animais , Abelhas/imunologia , Abelhas/parasitologia , Sinergismo Farmacológico , Feminino , Masculino , Polinização/efeitos dos fármacos
3.
Proc Natl Acad Sci U S A ; 121(28): e2408072121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38950363

RESUMO

Female mosquitoes produce eggs in gonadotrophic cycles that are divided between a previtellogenic and vitellogenic phase. Previtellogenic females consume water and sugar sources like nectar while also being attracted to hosts for blood feeding. Consumption of a blood meal activates the vitellogenic phase, which produces mature eggs and suppresses host attraction. In this study, we tested the hypothesis that neuropeptide Y-like hormones differentially modulate host attraction behavior in the mosquito Aedes aegypti. A series of experiments collectively indicated that enteroendocrine cells (EECs) in the posterior midgut produce and release neuropeptide F (NPF) into the hemolymph during the previtellogenic phase which stimulates attraction to humans and biting behavior. Consumption of a blood meal, which primarily consists of protein by dry weight, down-regulated NPF in EECs until mature eggs developed, which was associated with a decline in hemolymph titer. NPF depletion depended on protein digestion but was not associated with EEC loss. Other experiments showed that neurons in the terminal ganglion extend axons to the posterior midgut and produce RYamide, which showed evidence of increased secretion into circulation after a blood meal. Injection of RYamide-1 and -2 into previtellogenic females suppressed host attraction, while coinjection of RYamides with or without short NPF-2 also inhibited the host attraction activity of NPF. Overall, our results identify NPF and RYamide as gut-associated hormones in A. aegypti that link host attraction behavior to shifts in diet during sequential gonadotrophic cycles.


Assuntos
Aedes , Neuropeptídeos , Animais , Aedes/metabolismo , Aedes/fisiologia , Neuropeptídeos/metabolismo , Feminino , Comportamento Alimentar/fisiologia , Hemolinfa/metabolismo , Células Enteroendócrinas/metabolismo , Proteínas de Insetos/metabolismo , Humanos , Vitelogênese/fisiologia
4.
Nature ; 577(7788): 89-94, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31894144

RESUMO

Screening mammography aims to identify breast cancer at earlier stages of the disease, when treatment can be more successful1. Despite the existence of screening programmes worldwide, the interpretation of mammograms is affected by high rates of false positives and false negatives2. Here we present an artificial intelligence (AI) system that is capable of surpassing human experts in breast cancer prediction. To assess its performance in the clinical setting, we curated a large representative dataset from the UK and a large enriched dataset from the USA. We show an absolute reduction of 5.7% and 1.2% (USA and UK) in false positives and 9.4% and 2.7% in false negatives. We provide evidence of the ability of the system to generalize from the UK to the USA. In an independent study of six radiologists, the AI system outperformed all of the human readers: the area under the receiver operating characteristic curve (AUC-ROC) for the AI system was greater than the AUC-ROC for the average radiologist by an absolute margin of 11.5%. We ran a simulation in which the AI system participated in the double-reading process that is used in the UK, and found that the AI system maintained non-inferior performance and reduced the workload of the second reader by 88%. This robust assessment of the AI system paves the way for clinical trials to improve the accuracy and efficiency of breast cancer screening.


Assuntos
Inteligência Artificial/normas , Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Feminino , Humanos , Mamografia/normas , Reprodutibilidade dos Testes , Reino Unido , Estados Unidos
5.
Breast Cancer Res ; 26(1): 85, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807211

RESUMO

BACKGROUND: Abbreviated breast MRI (FAST MRI) is being introduced into clinical practice to screen women with mammographically dense breasts or with a personal history of breast cancer. This study aimed to optimise diagnostic accuracy through the adaptation of interpretation-training. METHODS: A FAST MRI interpretation-training programme (short presentations and guided hands-on workstation teaching) was adapted to provide additional training during the assessment task (interpretation of an enriched dataset of 125 FAST MRI scans) by giving readers feedback about the true outcome of each scan immediately after each scan was interpreted (formative assessment). Reader interaction with the FAST MRI scans used developed software (RiViewer) that recorded reader opinions and reading times for each scan. The training programme was additionally adapted for remote e-learning delivery. STUDY DESIGN: Prospective, blinded interpretation of an enriched dataset by multiple readers. RESULTS: 43 mammogram readers completed the training, 22 who interpreted breast MRI in their clinical role (Group 1) and 21 who did not (Group 2). Overall sensitivity was 83% (95%CI 81-84%; 1994/2408), specificity 94% (95%CI 93-94%; 7806/8338), readers' agreement with the true outcome kappa = 0.75 (95%CI 0.74-0.77) and diagnostic odds ratio = 70.67 (95%CI 61.59-81.09). Group 1 readers showed similar sensitivity (84%) to Group 2 (82% p = 0.14), but slightly higher specificity (94% v. 93%, p = 0.001). Concordance with the ground truth increased significantly with the number of FAST MRI scans read through the formative assessment task (p = 0.002) but by differing amounts depending on whether or not a reader had previously attended FAST MRI training (interaction p = 0.02). Concordance with the ground truth was significantly associated with reading batch size (p = 0.02), tending to worsen when more than 50 scans were read per batch. Group 1 took a median of 56 seconds (range 8-47,466) to interpret each FAST MRI scan compared with 78 (14-22,830, p < 0.0001) for Group 2. CONCLUSIONS: Provision of immediate feedback to mammogram readers during the assessment test set reading task increased specificity for FAST MRI interpretation and achieved high diagnostic accuracy. Optimal reading-batch size for FAST MRI was 50 reads per batch. Trial registration (25/09/2019): ISRCTN16624917.


Assuntos
Neoplasias da Mama , Curva de Aprendizado , Imageamento por Ressonância Magnética , Mamografia , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Pessoa de Meia-Idade , Detecção Precoce de Câncer/métodos , Estudos Prospectivos , Idoso , Sensibilidade e Especificidade , Interpretação de Imagem Assistida por Computador/métodos , Mama/diagnóstico por imagem , Mama/patologia
6.
Kidney Int ; 105(1): 35-45, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38182300

RESUMO

Integrated kidney care requires synergistic linkage between preventative care for people at risk for chronic kidney disease and health services providing care for people with kidney disease, ensuring holistic and coordinated care as people transition between acute and chronic kidney disease and the 3 modalities of kidney failure management: conservative kidney management, transplantation, and dialysis. People with kidney failure have many supportive care needs throughout their illness, regardless of treatment modality. Kidney supportive care is therefore a vital part of this integrated framework, but is nonexistent, poorly developed, and/or poorly integrated with kidney care in many settings, especially in low- and middle-income countries. To address this, the International Society of Nephrology has (i) coordinated the development of consensus definitions of conservative kidney management and kidney supportive care to promote international understanding and awareness of these active treatments; and (ii) identified key considerations for the development and expansion of conservative kidney management and kidney supportive care programs, especially in low resource settings, where access to kidney replacement therapy is restricted or not available. This article presents the definitions for conservative kidney management and kidney supportive care; describes their core components with some illustrative examples to highlight key points; and describes some of the additional considerations for delivering conservative kidney management and kidney supportive care in low resource settings.


Assuntos
Prestação Integrada de Cuidados de Saúde , Insuficiência Renal Crônica , Insuficiência Renal , Humanos , Rim , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/terapia , Tratamento Conservador
7.
Pediatr Res ; 95(1): 275-284, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37674022

RESUMO

BACKGROUND: Intrauterine exposure to hypertensive disorders of pregnancy, including gestational hypertension (GH) and preeclampsia (PE), may influence infant growth and have long-term health implications. This study aimed to compare growth outcomes of infants exposed to a normotensive pregnancy (NTP), GH, or PE from birth to 2 years. METHODS: Infants were children of women enroled in the prospective Postpartum Physiology, Psychology and Paediatric (P4) cohort study who had NTP, GH or PE. Birth, 6-month (age-corrected) and 2-year (age-corrected) weight z-scores, change in weight z-scores, rapid weight gain (≥0.67 increase in weight z-score) and conditional weight gain z-scores were calculated to assess infant growth (NTP = 240, GH = 19, PE = 66). RESULTS: Infants exposed to PE compared to NTP or GH had significantly lower birth weight and length z-scores, but there were no differences in growth outcomes at 6 months or 2 years. GH and PE-exposed infants had significantly greater weight z-score gain [95% CI] (PE = 0.93 [0.66-1.18], GH = 1.03 [0.37-1.68], NTP = 0.45 [0.31-0.58], p < 0.01) and rapid weight gain (GH = 63%, PE = 59%, NTP = 42%, p = 0.02) from birth to 2 years, which remained significant for PE-exposed infants after confounder adjustment. CONCLUSION: In this cohort, GH and PE were associated with accelerated infant weight gain that may increase future cardiometabolic disease risk. IMPACT: Preeclampsia exposed infants were smaller at birth, compared with normotensive pregnancy and gestational hypertension exposed infants, but caught up in growth by 2 years of age. Both preeclampsia and gestational hypertension exposed infants had significantly accelerated weight gain from birth to 2 years, which remained significant for preeclampsia exposed infants after adjustment for confounders including small for gestational age. Monitoring of growth patterns in infants born following exposure to a hypertensive disorder of pregnancy may be indicated to prevent accelerated weight gain trajectories and obesity.


Assuntos
Hipertensão Induzida pela Gravidez , Pré-Eclâmpsia , Recém-Nascido , Gravidez , Lactente , Humanos , Criança , Feminino , Estudos de Coortes , Estudos Prospectivos , Aumento de Peso
8.
Value Health ; 27(4): 469-477, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38307389

RESUMO

OBJECTIVES: The EQ-5D-5L is a commonly used health-related quality of life instrument for evaluating interventions in patients receiving dialysis; however, the minimal important difference (MID) that constitutes a meaningful treatment effect for this population has not been established. This study aims to estimate the MID for the EQ-5D-5L utility index in dialysis patients. METHODS: 6-monthly EQ-5D-5L measurements were collected from adult dialysis patients between April 2017 and November 2020 at a renal network in Sydney, Australia. EQ-VAS and Integrated Palliative care Outcome Scale Renal symptom burden scores were collected simultaneously and used as anchors. MID estimates for the EQ-5D-5L utility index were derived using anchor-based and distribution-based methods. RESULTS: A total of 352 patients with ≥1 EQ-5D-5L observation were included, constituting 1127 observations. Mean EQ-5D-5L utility index at baseline was 0.719 (SD ± 0.267), and mean EQ-5D-5L utility decreased over time by -0.017 per year (95% CI -0.029 to -0.006, P = .004). Using cross-sectional anchor-based methods, MID estimates ranged from 0.073 to 0.107. Using longitudinal anchor-based methods, MID for improvement and deterioration ranged from 0.046 to 0.079 and -0.111 to -0.048, respectively. Using receiver operating characteristic curves, MID for improvement and deterioration ranged from 0.037 to 0.122 and -0.074 to -0.063, respectively. MID estimates from distribution-based methods were consistent with anchor-based estimates. CONCLUSIONS: Anchor-based and distribution-based approaches provided EQ-5D-5L utility index MID estimates ranging from 0.034 to 0.134. These estimates can inform the target difference or "effect size" for clinical trial design among dialysis populations.


Assuntos
Qualidade de Vida , Diálise Renal , Adulto , Humanos , Estudos Transversais , Inquéritos e Questionários , Psicometria
9.
J Immunol ; 209(9): 1788-1795, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36113884

RESUMO

Chronic lung allograft dysfunction is the major barrier to long-term survival in lung transplant recipients. Evidence supports type 1 alloimmunity as the predominant response in acute/chronic lung rejection, but the immunoregulatory mechanisms remain incompletely understood. We studied the combinatorial F-box E3 ligase system: F-box protein 3 (FBXO3; proinflammatory) and F-box and leucine-rich repeat protein 2 (FBXL2; anti-inflammatory and regulates TNFR-associated factor [TRAF] protein). Using the mouse orthotopic lung transplant model, we evaluated allografts from BALB/c → C57BL/6 (acute rejection; day 10) and found significant induction of FBXO3 and diminished FBXL2 protein along with elevated T-bet, IFN-γ, and TRAF proteins 1-5 compared with isografts. In the acute model, treatment with costimulation blockade (MR1/CTLA4-Ig) resulted in attenuated FBXO3, preserved FBXL2, and substantially reduced T-bet, IFN-γ, and TRAFs 1-5, consistent with a key role for type 1 alloimmunity. Immunohistochemistry revealed significant changes in the FBXO3/FBXL2 balance in airway epithelia and infiltrating mononuclear cells during rejection compared with isografts or costimulation blockade-treated allografts. In the chronic lung rejection model, DBA/2J/C57BL/6F1 > DBA/2J (day 28), we observed persistently elevated FBXO3/FBXL2 balance and T-bet/IFN-γ protein and similar findings from lung transplant recipient lungs with chronic lung allograft dysfunction versus controls. We hypothesized that FBXL2 regulated T-bet and found FBXL2 was sufficient to polyubiquitinate T-bet and coimmunoprecipitated with T-bet on pulldown experiments and vice versa in Jurkat cells. Transfection with FBXL2 diminished T-bet protein in a dose-dependent manner in mouse lung epithelial cells. In testing type 1 cytokines, TNF-α was found to negatively regulate FBXL2 protein and mRNA levels. Together, our findings show the combinatorial E3 ligase FBXO3/FBXL2 system plays a role in the regulation of T-bet through FBXL2, with negative cross-regulation of TNF-α on FBXL2 during lung allograft rejection.


Assuntos
Proteínas F-Box , Animais , Camundongos , Abatacepte , Aloenxertos , Citocinas/metabolismo , Modelos Animais de Doenças , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Rejeição de Enxerto , Pulmão/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , RNA Mensageiro , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
10.
Nature ; 561(7721): 109-112, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30111837

RESUMO

Intensive agriculture currently relies on pesticides to maximize crop yield1,2. Neonicotinoids are the most widely used insecticides globally3, but increasing evidence of negative impacts on important pollinators4-9 and other non-target organisms10 has led to legislative reassessment and created demand for the development of alternative products. Sulfoximine-based insecticides are the most likely successor11, and are either licensed for use or under consideration for licensing in several worldwide markets3, including within the European Union12, where certain neonicotinoids (imidacloprid, clothianidin and thiamethoxam) are now banned from agricultural use outside of permanent greenhouse structures. There is an urgent need to pre-emptively evaluate the potential sub-lethal effects of sulfoximine-based pesticides on pollinators11, because such effects are rarely detected by standard ecotoxicological assessments, but can have major impacts at larger ecological scales13-15. Here we show that chronic exposure to the sulfoximine-based insecticide sulfoxaflor, at dosages consistent with potential post-spray field exposure, has severe sub-lethal effects on bumblebee (Bombus terrestris) colonies. Field-based colonies that were exposed to sulfoxaflor during the early growth phase produced significantly fewer workers than unexposed controls, and ultimately produced fewer reproductive offspring. Differences between the life-history trajectories of treated and control colonies first became apparent when individuals exposed as larvae began to emerge, suggesting that direct or indirect effects on a small cohort may have cumulative long-term consequences for colony fitness. Our results caution against the use of sulfoximines as a direct replacement for neonicotinoids. To avoid continuing cycles of novel pesticide release and removal, with concomitant impacts on the environment, a broad evidence base needs to be assessed prior to the development of policy and regulation.


Assuntos
Abelhas/efeitos dos fármacos , Abelhas/fisiologia , Inseticidas/efeitos adversos , Piridinas/efeitos adversos , Compostos de Enxofre/efeitos adversos , Animais , Feminino , Inseticidas/administração & dosagem , Masculino , Dinâmica Populacional , Piridinas/administração & dosagem , Reprodução/efeitos dos fármacos , Compostos de Enxofre/administração & dosagem
12.
J Comput Assist Tomogr ; 48(1): 1-11, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37574655

RESUMO

ABSTRACT: The Fontan procedure is the definitive treatment for patients with single-ventricle physiology. Surgical advances have led to a growing number of patients surviving into adulthood. Fontan-associated liver disease (FALD) encompasses a spectrum of pathologic liver changes that occur secondary to altered physiology including congestion, fibrosis, and the development of liver masses. Assessment of FALD is difficult and relies on using imaging alongside of clinical, laboratory, and pathology information. Ultrasound, computed tomography, and magnetic resonance imaging are capable of demonstrating physiologic and hepatic parenchymal abnormalities commonly seen in FALD. Several novel imaging techniques including magnetic resonance elastography are under study for use as biomarkers for FALD progression. Imaging has a central role in detection and characterization of liver masses as benign or malignant. Benign FNH-like masses are commonly encountered; however, these can display atypical features and be mistaken for hepatocellular carcinoma (HCC). Fontan patients are at elevated risk for HCC, which is a feared complication and has a poor prognosis in this population. While imaging screening for HCC is widely advocated, no consensus has been reached regarding an optimal surveillance regimen.


Assuntos
Carcinoma Hepatocelular , Hepatopatias , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Hepatopatias/diagnóstico por imagem , Fígado/diagnóstico por imagem , Ultrassonografia , Fibrose , Cirrose Hepática
13.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34772810

RESUMO

We generalize Taylor's law for the variance of light-tailed distributions to many sample statistics of heavy-tailed distributions with tail index α in (0, 1), which have infinite mean. We show that, as the sample size increases, the sample upper and lower semivariances, the sample higher moments, the skewness, and the kurtosis of a random sample from such a law increase asymptotically in direct proportion to a power of the sample mean. Specifically, the lower sample semivariance asymptotically scales in proportion to the sample mean raised to the power 2, while the upper sample semivariance asymptotically scales in proportion to the sample mean raised to the power [Formula: see text] The local upper sample semivariance (counting only observations that exceed the sample mean) asymptotically scales in proportion to the sample mean raised to the power [Formula: see text] These and additional scaling laws characterize the asymptotic behavior of commonly used measures of the risk-adjusted performance of investments, such as the Sortino ratio, the Sharpe ratio, the Omega index, the upside potential ratio, and the Farinelli-Tibiletti ratio, when returns follow a heavy-tailed nonnegative distribution. Such power-law scaling relationships are known in ecology as Taylor's law and in physics as fluctuation scaling. We find the asymptotic distribution and moments of the number of observations exceeding the sample mean. We propose estimators of α based on these scaling laws and the number of observations exceeding the sample mean and compare these estimators with some prior estimators of α.

14.
Proc Natl Acad Sci U S A ; 118(15)2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33827929

RESUMO

We previously determined that several diets used to rear Aedes aegypti and other mosquito species support the development of larvae with a gut microbiota but do not support the development of axenic larvae. In contrast, axenic larvae have been shown to develop when fed other diets. To understand the mechanisms underlying this dichotomy, we developed a defined diet that could be manipulated in concert with microbiota composition and environmental conditions. Initial studies showed that axenic larvae could not grow under standard rearing conditions (27 °C, 16-h light: 8-h dark photoperiod) when fed a defined diet but could develop when maintained in darkness. Downstream assays identified riboflavin decay to lumichrome as the key factor that prevented axenic larvae from growing under standard conditions, while gut community members like Escherichia coli rescued development by being able to synthesize riboflavin. Earlier results showed that conventional and gnotobiotic but not axenic larvae exhibit midgut hypoxia under standard rearing conditions, which correlated with activation of several pathways with essential growth functions. In this study, axenic larvae in darkness also exhibited midgut hypoxia and activation of growth signaling but rapidly shifted to midgut normoxia and arrested growth in light, which indicated that gut hypoxia was not due to aerobic respiration by the gut microbiota but did depend on riboflavin that only resident microbes could provide under standard conditions. Overall, our results identify riboflavin provisioning as an essential function for the gut microbiota under most conditions A. aegypti larvae experience in the laboratory and field.


Assuntos
Aedes/crescimento & desenvolvimento , Microbioma Gastrointestinal , Riboflavina/biossíntese , Aedes/microbiologia , Animais , Escherichia coli/metabolismo , Escherichia coli/patogenicidade
15.
J Ren Nutr ; 34(2): 177-184, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37918642

RESUMO

BACKGROUND: Frailty and malnutrition are both associated with worsening morbidity and mortality and become more prevalent in the elderly and as kidney function declines. Anorexia and reduced oral intake are common features of both frailty and malnutrition. However, there are sparse data evaluating the impact of other gastrointestinal (GI) symptoms, such as taste changes, on rates of frailty and malnutrition in people with kidney failure. The aim of this study is to describe the prevalence of frailty and malnutrition and their association with dietary intake and nutrition-related symptoms in people with kidney failure. METHODS: This observational study recruited people with kidney failure who were commencing Conservative Kidney Management or elderly people (aged > 75 years) newly commenced on dialysis from 3 renal units. Participants underwent assessments of frailty, nutritional status, dietary intake, and GI symptom burden when they attended clinic appointments, approximately every 6 months. RESULTS: Of the 85 participants, 57% were assessed as being frail and 33% were assessed as being malnourished. Participants assessed as frail reported more GI symptoms (3 vs. 2, P < .001) that were more severe (1.75 vs. 1.0, P < .001) compared to nonfrail participants. Being malnourished was associated with a 5 times higher chance of being frail (odds ratio 5.8; 95% confidence interval 1.5, 21.8; P = .015) and having more severe symptoms was associated with a 2 times higher chance (odds ratio 2.8; 95% CI 1.1, 7.0; P = .026) of being frail. In addition to experiencing more GI symptoms, that were more severe, participants who were malnourished consumed significantly less energy (1234 kcal vs. 1400 kcal, P = .01) and protein (51 g vs. 74 g, P < .001). CONCLUSIONS: Frailty and malnutrition are common and are associated with a higher GI symptom burden and poorer dietary intake. Future research is needed to determine effective interventions targeting frailty and malnutrition, including nutrition-related symptoms and optimal protein intake.


Assuntos
Fragilidade , Desnutrição , Insuficiência Renal , Idoso , Humanos , Fragilidade/epidemiologia , Fragilidade/complicações , Estudos Prospectivos , Avaliação Nutricional , Desnutrição/diagnóstico , Estado Nutricional , Ingestão de Alimentos , Insuficiência Renal/complicações , Insuficiência Renal/epidemiologia , Idoso Fragilizado , Avaliação Geriátrica
16.
Health Rep ; 35(3): 3-17, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38527107

RESUMO

Background: Small area estimation refers to statistical modelling procedures that leverage information or "borrow strength" from other sources or variables. This is done to enhance the reliability of estimates of characteristics or outcomes for areas that do not contain sufficient sample sizes to provide disaggregated estimates of adequate precision and reliability. There is growing interest in secondary research applications for small area estimates (SAEs). However, it is crucial to assess the analytic value of these estimates when used as proxies for individual-level characteristics or as distinct measures that offer insights at the area level. This study assessed novel area-level community belonging measures derived using small area estimation and examined associations with individual-level measures of community belonging and self-rated health. Data and methods: SAEs of community belonging within census tracts produced from the 2016-2019 cycles of the Canadian Community Health Survey (CCHS) were merged with respondent data from the 2020 CCHS. Multinomial logistic regression models were run between area-level SAEs, individual-level sense of community belonging, and self-rated health on the study sample of people aged 18 years and older. Results: Area-level community belonging was associated with individual-level community belonging, even after adjusting for individual-level sociodemographic characteristics, despite limited agreement between individual- and area-level measures. Living in a neighbourhood with low community belonging was associated with higher odds of reporting being in fair or poor health, versus being in very good or excellent health (odds ratio: 1.53; 95% confidence interval: 1.22, 1.91), even after adjusting for other factors such as individual-level sense of community belonging, which was also associated with self-rated health. Interpretation: Area-level and individual-level sense of community belonging were independently associated with self-rated health. The novel SAEs of community belonging can be used as distinct measures of neighbourhood-level community belonging and should be understood as complementary to, rather than proxies for, individual-level measures of community belonging.


Assuntos
Nível de Saúde , Características de Residência , Humanos , Fatores Socioeconômicos , Reprodutibilidade dos Testes , Canadá , Inquéritos Epidemiológicos
17.
Altern Lab Anim ; 52(3): 149-154, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38606566

RESUMO

In the cosmetics sector, many products such as shampoos have a probability of accidental ocular exposure during their routine use. One very specific safety parameter is the residence time of the substance on the corneal surface, as prolonged exposure may cause injury. In this study, we developed a system that simulates corneal exposure to blinking and tear flow, for comparing the corneal clearance times of viscous detergent formulations. The Ex Vivo Eye Irritation Test (EVEIT), which uses corneal explants from discarded rabbit eyes from an abattoir, was used as the basis for the new system. To simulate blinking, we developed a silicone wiping membrane to regularly move across the corneal surface, under conditions of constant addition and aspiration of fluid, to mimic tear flow. Six shampoo formulations were tested and were shown to differ widely in their corneal clearance time. Three groups could be identified according to the observed clearance times (fast, intermediate and slow); the reference shampoo had the shortest clearance time of all tested formulations. With this new system, it is now possible to investigate an important physicochemical parameter, i.e. corneal clearance time, for the consideration of ocular safety during the development of novel cosmetic formulations.


Assuntos
Piscadela , Córnea , Animais , Coelhos , Córnea/efeitos dos fármacos , Piscadela/efeitos dos fármacos , Alternativas aos Testes com Animais/métodos , Preparações para Cabelo , Lágrimas/efeitos dos fármacos
18.
Lancet ; 400(10352): 605-615, 2022 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-35988569

RESUMO

BACKGROUND: Anterior cruciate ligament (ACL) rupture is a common debilitating injury that can cause instability of the knee. We aimed to investigate the best management strategy between reconstructive surgery and non-surgical treatment for patients with a non-acute ACL injury and persistent symptoms of instability. METHODS: We did a pragmatic, multicentre, superiority, randomised controlled trial in 29 secondary care National Health Service orthopaedic units in the UK. Patients with symptomatic knee problems (instability) consistent with an ACL injury were eligible. We excluded patients with meniscal pathology with characteristics that indicate immediate surgery. Patients were randomly assigned (1:1) by computer to either surgery (reconstruction) or rehabilitation (physiotherapy but with subsequent reconstruction permitted if instability persisted after treatment), stratified by site and baseline Knee Injury and Osteoarthritis Outcome Score-4 domain version (KOOS4). This management design represented normal practice. The primary outcome was KOOS4 at 18 months after randomisation. The principal analyses were intention-to-treat based, with KOOS4 results analysed using linear regression. This trial is registered with ISRCTN, ISRCTN10110685, and ClinicalTrials.gov, NCT02980367. FINDINGS: Between Feb 1, 2017, and April 12, 2020, we recruited 316 patients. 156 (49%) participants were randomly assigned to the surgical reconstruction group and 160 (51%) to the rehabilitation group. Mean KOOS4 at 18 months was 73·0 (SD 18·3) in the surgical group and 64·6 (21·6) in the rehabilitation group. The adjusted mean difference was 7·9 (95% CI 2·5-13·2; p=0·0053) in favour of surgical management. 65 (41%) of 160 patients allocated to rehabilitation underwent subsequent surgery according to protocol within 18 months. 43 (28%) of 156 patients allocated to surgery did not receive their allocated treatment. We found no differences between groups in the proportion of intervention-related complications. INTERPRETATION: Surgical reconstruction as a management strategy for patients with non-acute ACL injury with persistent symptoms of instability was clinically superior and more cost-effective in comparison with rehabilitation management. FUNDING: The UK National Institute for Health Research Health Technology Assessment Programme.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Traumatismos do Joelho , Lesões do Ligamento Cruzado Anterior/diagnóstico , Lesões do Ligamento Cruzado Anterior/etiologia , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/efeitos adversos , Reconstrução do Ligamento Cruzado Anterior/métodos , Humanos , Traumatismos do Joelho/etiologia , Traumatismos do Joelho/reabilitação , Traumatismos do Joelho/cirurgia , Articulação do Joelho/cirurgia , Medicina Estatal , Resultado do Tratamento
19.
Oncologist ; 28(12): e1268-e1278, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37343145

RESUMO

BACKGROUND: This phase III, randomized, double-blind, placebo-controlled, parallel-group study assessed the efficacy and safety of tanezumab in subjects with cancer pain predominantly due to bone metastasis receiving background opioid therapy. METHODS: Subjects were randomized (stratified by (1) tumor aggressiveness and (2) presence/absence of concomitant anticancer treatment) to placebo or tanezumab 20 mg. Treatment was administered by subcutaneous injection every 8 weeks for 24 weeks (3 doses) followed by a 24-week safety follow-up period. The primary outcome was change in daily average pain in the index bone metastasis cancer pain site (from 0 = no pain to 10 = worst possible pain) from baseline to week 8. RESULTS: LS mean (SE) change in pain at week 8 was -1.25 (0.35) for placebo (n = 73) and -2.03 (0.35) for tanezumab 20 mg (n = 72). LS mean (SE) [95% CI] difference from placebo was -0.78 (0.37) [-1.52, -0.04]; P = .0381 with α = 0.0478. The number of subjects with a treatment-emergent adverse event during the treatment period was 50 (68.5%) for placebo and 53 (73.6%) for tanezumab 20 mg. The number of subjects with a prespecified joint safety event was 0 for placebo and 2 (2.8%) for tanezumab 20 mg (pathologic fracture; n = 2). CONCLUSION: Tanezumab 20 mg met the primary efficacy endpoint at week 8. Conclusions on longer-term efficacy are limited since the study was not designed to evaluate the durability of the effect beyond 8 weeks. Safety findings were consistent with adverse events expected in subjects with cancer pain due to bone metastasis and the known safety profile of tanezumab. Clinicaltrials.gov identifier: NCT02609828.


Assuntos
Neoplasias Ósseas , Dor do Câncer , Humanos , Dor do Câncer/tratamento farmacológico , Resultado do Tratamento , Dor/induzido quimicamente , Anticorpos Monoclonais Humanizados/efeitos adversos , Neoplasias Ósseas/complicações , Neoplasias Ósseas/tratamento farmacológico , Método Duplo-Cego
20.
Environ Microbiol ; 25(6): 1084-1098, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36700447

RESUMO

Bacterioplankton communities govern marine productivity and biogeochemical cycling, yet drivers of bacterioplankton assembly remain unclear. Here, we contrast the relative contribution of deterministic processes (environmental factors and biotic interactions) in driving temporal dynamics of bacterioplankton diversity at three different oceanographic time series locations, spanning 15° of latitude, which are each characterized by different environmental conditions and varying degrees of seasonality. Monthly surface samples (5.5 years) were analysed using 16S rRNA amplicon sequencing. The high- and mid-latitude sites of Maria Island and Port Hacking were characterized by high and intermediate levels of environmental heterogeneity, respectively, with both alpha diversity (72%; 24% of total variation) and beta diversity (32%; 30%) patterns within bacterioplankton assemblages explained by day length, ammonium, and mixed layer depth. In contrast, North Stradbroke Island, a sub-tropical location where environmental conditions are less variable, interspecific interactions were of increased importance in structuring bacterioplankton diversity (alpha: 33%; beta: 26%) with environment only contributing 11% and 13% to predicting diversity, respectively. Our results demonstrate that bacterioplankton diversity is the result of both deterministic environmental and biotic processes and that the importance of these different deterministic processes varies, potential in response to environmental heterogeneity.


Assuntos
Organismos Aquáticos , Ecossistema , RNA Ribossômico 16S/genética , Plâncton/genética
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