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1.
Nature ; 628(8007): 355-358, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38030722

RESUMEN

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.


Asunto(s)
Insecticidas , Plaguicidas , Abejas , Animales , Plaguicidas/toxicidad , Insecticidas/toxicidad , Neonicotinoides/toxicidad , Agricultura , Polen
2.
Nature ; 596(7872): 389-392, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34349259

RESUMEN

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.


Asunto(s)
Agroquímicos/efectos adversos , Agroquímicos/envenenamiento , Abejas/efectos de los fármacos , Estrés Fisiológico/efectos de los fármacos , Agricultura , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Abejas/inmunología , Abejas/parasitología , Sinergismo Farmacológico , Femenino , Masculino , Polinización/efectos de los fármacos
3.
Proc Natl Acad Sci U S A ; 121(28): e2408072121, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38950363

RESUMEN

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.


Asunto(s)
Aedes , Neuropéptidos , Animales , Aedes/metabolismo , Aedes/fisiología , Neuropéptidos/metabolismo , Femenino , Conducta Alimentaria/fisiología , Hemolinfa/metabolismo , Células Enteroendocrinas/metabolismo , Proteínas de Insectos/metabolismo , Humanos , Vitelogénesis/fisiología
4.
Nature ; 577(7788): 89-94, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894144

RESUMEN

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.


Asunto(s)
Inteligencia Artificial/normas , Neoplasias de la Mama/diagnóstico por imagen , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/normas , Femenino , Humanos , Mamografía/normas , Reproducibilidad de los Resultados , Reino Unido , Estados Unidos
5.
Breast Cancer Res ; 26(1): 85, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807211

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama , Curva de Aprendizaje , Imagen por Resonancia Magnética , Mamografía , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética/métodos , Mamografía/métodos , Persona de Mediana Edad , Detección Precoz del Cáncer/métodos , Estudios Prospectivos , Anciano , Sensibilidad y Especificidad , Interpretación de Imagen Asistida por Computador/métodos , Mama/diagnóstico por imagen , Mama/patología
6.
Int J Cancer ; 2024 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-39394862

RESUMEN

Digital breast tomosynthesis (DBT) with full-field digital mammography (FFDM) exposes women to a higher radiation dose. A synthetic 2D mammogram (S2D) is a two-dimensional image constructed from DBT. We aim to evaluate the S2D performance when used alone or combined with DBT compared to FFDM alone or with DBT. Studies were included if they recruited screening participants and reported on S2D performance. Studies were excluded if they included symptomatic patients, imaging was for diagnostic purposes, or if participants had a breast cancer history. Meta-analyses for cancer detection rates (CDR) and Specificities were conducted where available. Differences in the performance of imaging modalities were calculated within individual studies, and these were pooled by meta-analysis. Out of 3241 records identified, 17 studies were included in the review and 13 in the meta-analysis. The estimated combined difference in CDRs per thousand among individual studies that reported on DBT plus S2D vs. FFDM and those reporting on DBT plus S2D versus DBT plus FFDM was 2.03 (95% CI 0.81-3.25) and - 0.15 (95% CI -1.17 to 0.86), respectively. The estimated difference in percent specificities was 1.13 (95% CI -0.06 to 2.31) in studies comparing DBT plus S2D and FFDM. In studies comparing DBT plus S2D and DBT plus FFDM, the estimated difference in specificities was 1.08 (95% CI 0.59-1.56). DBT plus S2D showed comparable accuracy to FFDM plus DPT and improved cancer detection to FFDM alone. Integrating S2D with DBT in breast cancer screening is safe and preserves performance.

7.
Kidney Int ; 105(1): 35-45, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38182300

RESUMEN

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.


Asunto(s)
Prestación Integrada de Atención de Salud , Insuficiencia Renal Crónica , Insuficiencia Renal , Humanos , Riñón , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/terapia , Tratamiento Conservador
8.
Pediatr Res ; 95(1): 275-284, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37674022

RESUMEN

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.


Asunto(s)
Hipertensión Inducida en el Embarazo , Preeclampsia , Recién Nacido , Embarazo , Lactante , Humanos , Niño , Femenino , Estudios de Cohortes , Estudios Prospectivos , Aumento de Peso
9.
Value Health ; 27(4): 469-477, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38307389

RESUMEN

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.


Asunto(s)
Calidad de Vida , Diálisis Renal , Adulto , Humanos , Estudios Transversales , Encuestas y Cuestionarios , Psicometría
10.
J Immunol ; 209(9): 1788-1795, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36113884

RESUMEN

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.


Asunto(s)
Proteínas F-Box , Animales , Ratones , Abatacept , Aloinjertos , Citocinas/metabolismo , Modelos Animales de Enfermedad , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Rechazo de Injerto , Pulmón/metabolismo , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , ARN Mensajero , Péptidos y Proteínas Asociados a Receptores de Factores de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
11.
Nature ; 561(7721): 109-112, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30111837

RESUMEN

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.


Asunto(s)
Abejas/efectos de los fármacos , Abejas/fisiología , Insecticidas/efectos adversos , Piridinas/efectos adversos , Compuestos de Azufre/efectos adversos , Animales , Femenino , Insecticidas/administración & dosificación , Masculino , Dinámica Poblacional , Piridinas/administración & dosificación , Reproducción/efectos de los fármacos , Compuestos de Azufre/administración & dosificación
13.
J Comput Assist Tomogr ; 48(1): 1-11, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37574655

RESUMEN

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.


Asunto(s)
Carcinoma Hepatocelular , Hepatopatías , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Hepatopatías/diagnóstico por imagen , Hígado/diagnóstico por imagen , Ultrasonografía , Fibrosis , Cirrosis Hepática
14.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34772810

RESUMEN

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.

15.
Proc Natl Acad Sci U S A ; 118(15)2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33827929

RESUMEN

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.


Asunto(s)
Aedes/crecimiento & desarrollo , Microbioma Gastrointestinal , Riboflavina/biosíntesis , Aedes/microbiología , Animales , Escherichia coli/metabolismo , Escherichia coli/patogenicidad
16.
J Ren Nutr ; 34(2): 177-184, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37918642

RESUMEN

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.


Asunto(s)
Fragilidad , Desnutrición , Insuficiencia Renal , Anciano , Humanos , Fragilidad/epidemiología , Fragilidad/complicaciones , Estudios Prospectivos , Evaluación Nutricional , Desnutrición/diagnóstico , Estado Nutricional , Ingestión de Alimentos , Insuficiencia Renal/complicaciones , Insuficiencia Renal/epidemiología , Anciano Frágil , Evaluación Geriátrica
17.
Health Rep ; 35(3): 3-17, 2024 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-38527107

RESUMEN

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.


Asunto(s)
Estado de Salud , Características de la Residencia , Humanos , Factores Socioeconómicos , Reproducibilidad de los Resultados , Canadá , Encuestas Epidemiológicas
18.
Artículo en Inglés | MEDLINE | ID: mdl-39333028

RESUMEN

BACKGROUND: Current understanding of clinical practice and care for maternal kidney disease in pregnancy in Australia is hampered by limitations in available renal-specific datasets. AIMS: To capture the epidemiology, management, and outcomes of women with significant kidney disease in pregnancy and demonstrate feasibility of a national cohort study approach. MATERIALS AND METHODS: An Australian prospective study (2017-2018) using a new kidney disease-specific survey within the Australasian Maternity Outcomes Surveillance System (AMOSS). Women who gave birth with acute kidney injury (AKI), advanced chronic kidney disease (CKD), dialysis dependence or a kidney transplant were included. Demographic data, renal and obstetric management, and perinatal outcomes were collected. RESULTS: Among 58 case notifications from 12 hospitals in five states, we included 23 cases with kidney transplant (n = 12), pre-existing CKD (n = 8), newly diagnosed CKD (n = 2) and dialysis (n = 1). No cases of AKI were reported. Reporting rates were better in states with study investigators and, overall, cases were likely under-reported. Nearly 35% of women had a non-delivery-related antenatal admission. Nephrology involvement was 78.3% during pregnancy and 91% post-partum. Adverse events were increased, including pre-eclampsia (21.7%), and preterm birth (60.9%). Women had high rates of aspirin (82.6%) and antihypertensive (73.9%) use, indwelling catheter for labour/delivery (65.2%), caesarean delivery (60.9%), and blood transfusion (21.7%). CONCLUSIONS: This first-ever Australian prospective study of significant kidney diseases in pregnancy provided novel insights into renal-specific clinical patterns and practices. However, under-reporting was likely. Future studies need to overcome the challenges of case identification and data collection burden.

19.
Altern Lab Anim ; 52(3): 149-154, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38606566

RESUMEN

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.


Asunto(s)
Parpadeo , Córnea , Animales , Conejos , Córnea/efectos de los fármacos , Parpadeo/efectos de los fármacos , Alternativas a las Pruebas en Animales/métodos , Preparaciones para el Cabello , Lágrimas/efectos de los fármacos
20.
Medicina (Kaunas) ; 60(9)2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39336453

RESUMEN

Background and Subject: Hyponatraemia is a common electrolyte disorder. For patients with severe hyponatraemia, intensive care unit (ICU) admission may be required. This will enable close monitoring and allow safe management of sodium levels effectively. While severe hyponatraemia may be associated with significant symptoms, rapid overcorrection of hyponatraemia can lead to complications. We aimed to describe the management and outcomes of severe hyponatraemia in our ICU and identify risk factors for overcorrection. Materials and Methods: This was a retrospective single-centre cohort that included consecutive adults admitted to the ICU with serum sodium < 120 mmol/L between 1 January 2017 and 8 March 2023. Anonymised data were collected from electronic records. We included 181 patients (median age 67 years, 51% male). Results: Median admission serum sodium was 113 mmol/L (IQR: 108-117), with an average rate of improvement over the first 48 h of 10 mmol/L/day (IQR: 5-15 mmol/L). A total of 62 patients (34%) met the criteria for overcorrection at 48 h, and they were younger, presented with severe symptoms (seizures/arrythmias), and had lower admission sodium concentration. They were more likely to be treated with hypertonic saline infusions. Lower admission sodium was an independent risk factor for overcorrection within 48 h, whereas the presence of liver cirrhosis and fluid restriction was associated with normal correction. No difference was identified between the normal and overcorrected cohorts for ICU/hospital length of stay or mortality. Conclusions: In some patients with severe hyponatraemia, overcorrection is inevitable to avoid symptoms such as seizures and arrhythmias, and consequently, we highlight the key factors associated with overcorrection. Overall, we identified that overcorrection was common and concordant with the current literature.


Asunto(s)
Cuidados Críticos , Hiponatremia , Unidades de Cuidados Intensivos , Humanos , Hiponatremia/terapia , Masculino , Femenino , Anciano , Estudios Retrospectivos , Persona de Mediana Edad , Cuidados Críticos/métodos , Cuidados Críticos/estadística & datos numéricos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Factores de Riesgo , Estudios de Cohortes , Sodio/sangre , Anciano de 80 o más Años
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