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Chemotherapy is notorious for causing behavioral side effects (e.g., cognitive decline). Notably, the gut microbiome has recently been reported to communicate with the brain to affect behavior, including cognition. Thus, the aim of this clinical longitudinal observational study was to determine whether chemotherapy-induced disruption of the gut microbial community structure relates to cognitive decline and circulating inflammatory signals. Fecal samples, blood, and cognitive measures were collected from 77 patients with breast cancer before, during, and after chemotherapy. Chemotherapy altered the gut microbiome community structure and increased circulating TNF-α. Both the chemotherapy-induced changes in microbial relative abundance and decreased microbial diversity were related to elevated circulating pro-inflammatory cytokines TNF-α and IL-6. Participants reported subjective cognitive decline during chemotherapy, which was not related to changes in the gut microbiome or inflammatory markers. In contrast, a decrease in overall objective cognition was related to a decrease in microbial diversity, independent of circulating cytokines. Stratification of subjects, via a reliable change index based on 4 objective cognitive tests, identified objective cognitive decline in 35% of the subjects. Based on a differential microbial abundance analysis, those characterized by cognitive decline had unique taxonomic shifts (Faecalibacterium, Bacteroides, Fusicatenibacter, Erysipelotrichaceae UCG-003, and Subdoligranulum) over chemotherapy treatment compared to those without cognitive decline. Taken together, gut microbiome change was associated with cognitive decline during chemotherapy, independent of chemotherapy-induced inflammation. These results suggest that microbiome-related strategies may be useful for predicting and preventing behavioral side effects of chemotherapy.
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Neoplasias da Mama , Disfunção Cognitiva , Microbioma Gastrointestinal , Inflamação , Humanos , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Pessoa de Meia-Idade , Disfunção Cognitiva/microbiologia , Disfunção Cognitiva/induzido quimicamente , Inflamação/microbiologia , Estudos Longitudinais , Adulto , Antineoplásicos/efeitos adversos , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/sangue , Idoso , Interleucina-6/sangue , Interleucina-6/metabolismo , Fezes/microbiologia , Citocinas/metabolismo , Citocinas/sangue , Cognição/efeitos dos fármacosRESUMO
Examples of biochar as an alternative to traditional plastic fillers, like carbon black, are numerous and growing. However, in the agricultural mulch film application, both the polymer and its fillers are pushed to their mechanical limit to obtain an effective product, using the least amount of plastic. Through a combined techno-economic analysis (TEA) and life cycle assessment (LCA), this study characterizes the use of carbon-negative biochar as an opacity filler in mulch film applications. Due to its larger particle size, the biochar demands additional thickness to achieve equivalent opacity as carbon black in films. A thicker film translates to additional polymer demand, and a significant increase in price and environmental impact. A comparable formulation for an equal price ($623 per mulched ha) as a 2.6 wt % carbon black with 25 µm thickness was derived, needing 15 wt % biochar and a thickness of 30 µm. The biochar formulation resulted in a slightly higher global warming potential (3% increase), but much larger impact in the land use category (+339%), and the sample was deemed not fit for use in the intended mulch application. These results indicate that in applications where the polymeric matrix and its fillers are pushed to their mechanical limit, the displacement of traditional fillers by biochar is challenging. However, biochar derived from waste biomass (thus reducing land use impact) remains a valid, environmentally beneficial solution to displace traditional fillers for non-extreme plastic uses (commodity plastics) and thicker composites.
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Carvão Vegetal , Fuligem , Agricultura/métodos , Carbono , Polímeros , SoloRESUMO
Modules in brain functional connectomes are essential to balancing segregation and integration of neuronal activity. Connectomes are the complete set of pairwise connections between brain regions. Non-invasive Electroencephalography (EEG) and Magnetoencephalography (MEG) have been used to identify modules in connectomes of phase-synchronization. However, their resolution is suboptimal because of spurious phase-synchronization due to EEG volume conduction or MEG field spread. Here, we used invasive, intracerebral recordings from stereo-electroencephalography (SEEG, N = 67), to identify modules in connectomes of phase-synchronization. To generate SEEG-based group-level connectomes affected only minimally by volume conduction, we used submillimeter accurate localization of SEEG contacts and referenced electrode contacts in cortical gray matter to their closest contacts in white matter. Combining community detection methods with consensus clustering, we found that the connectomes of phase-synchronization were characterized by distinct and stable modules at multiple spatial scales, across frequencies from 3 to 320 Hz. These modules were highly similar within canonical frequency bands. Unlike the distributed brain systems identified with functional Magnetic Resonance Imaging (fMRI), modules up to the high-gamma frequency band comprised only anatomically contiguous regions. Notably, the identified modules comprised cortical regions involved in shared repertoires of sensorimotor and cognitive functions including memory, language and attention. These results suggest that the identified modules represent functionally specialised brain systems, which only partially overlap with the brain systems reported with fMRI. Hence, these modules might regulate the balance between functional segregation and functional integration through phase-synchronization.
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Conectoma , Humanos , Encéfalo/fisiologia , Magnetoencefalografia/métodos , Eletroencefalografia/métodos , Mapeamento Encefálico/métodos , Imageamento por Ressonância MagnéticaRESUMO
Large-scale networks of phase synchronization are considered to regulate the communication between brain regions fundamental to cognitive function, but the mapping to their structural substrates, i.e., the structure-function relationship, remains poorly understood. Biophysical Network Models (BNMs) have demonstrated the influences of local oscillatory activity and inter-regional anatomical connections in generating alpha-band (8-12 Hz) networks of phase synchronization observed with Electroencephalography (EEG) and Magnetoencephalography (MEG). Yet, the influence of inter-regional conduction delays remains unknown. In this study, we compared a BNM with standard "distance-dependent delays", which assumes constant conduction velocity, to BNMs with delays specified by two alternative methods accounting for spatially varying conduction velocities, "isochronous delays" and "mixed delays". We followed the Approximate Bayesian Computation (ABC) workflow, i) specifying neurophysiologically informed prior distributions of BNM parameters, ii) verifying the suitability of the prior distributions with Prior Predictive Checks, iii) fitting each of the three BNMs to alpha-band MEG resting-state data (N = 75) with Bayesian optimization for Likelihood-Free Inference (BOLFI), and iv) choosing between the fitted BNMs with ABC model comparison on a separate MEG dataset (N = 30). Prior Predictive Checks revealed the range of dynamics generated by each of the BNMs to encompass those seen in the MEG data, suggesting the suitability of the prior distributions. Fitting the models to MEG data yielded reliable posterior distributions of the parameters of each of the BNMs. Finally, model comparison revealed the BNM with "distance-dependent delays", as the most probable to describe the generation of alpha-band networks of phase synchronization seen in MEG. These findings suggest that distance-dependent delays might contribute to the neocortical architecture of human alpha-band networks of phase synchronization. Hence, our study illuminates the role of inter-regional delays in generating the large-scale networks of phase synchronization that might subserve the communication between regions vital to cognition.
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Encéfalo , Magnetoencefalografia , Humanos , Teorema de Bayes , Encéfalo/fisiologia , Magnetoencefalografia/métodos , Eletroencefalografia/métodos , Mapeamento Encefálico/métodosRESUMO
BACKGROUND: The COVID-19 pandemic has necessitated significant changes to the manner in which healthcare is delivered. Chief among these has been the need to rapidly adopt virtual, or telephone clinics as a means of reducing unnecessary patient exposure to hospitals and clinical care settings. We were greatly aided in our adoption of virtual clinics by our experience in the establishment and maintenance of a Clinical Nurse Specialist-led, virtual clinic for both abdominal aortic (AAA) and extra-aortic aneurysm (EAA) surveillance within our department since 2016. Patients undergoing surveillance for abdominal aortic aneurysm (AAA) require frequent and lifelong clinical review. Previous studies have shown that post-operative surveillance in particular is critical in prolonging survival in AAA patients and in the early detection of late complications particularly following endovascular repair (EVAR). Poor compliance with EVAR surveillance has been shown to result in worse outcomes. AIM: The aim of this study was to evaluate the success of a nurse-led virtual clinic programme in terms of the safe management of patients undergoing AAA surveillance in a nurse-led virtual clinic. RESULTS: Over the course of the 4-year period from 2016 to 2019, 1352 patients were enrolled in the virtual aneurysm surveillance clinic. The majority of patients each year were male, ranging from 78.2% in 2016 to 85.2% in 2017. The majority of patients encountered the service owing to pre-operative surveillance of an AAA, with this group comprising at least 65% of the total cohort of patients each year.Over the course of the 4-year period of the virtual clinic there were 1466 patient encounters. Each ambulatory day care centre (ADCC) attendance normally costs the hospital 149. Therefore, a total saving of 218,434 resulted from this initiative alone. No patient presented as an emergency with a ruptured aneurysm during the time period studied. CONCLUSION: Patients with AAA can be safely kept under surveillance in a nurse-led virtual clinic. Our experience with this model of care proved to be particularly advantageous during the period of the early COVID-19 pandemic.
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Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , COVID-19 , Procedimentos Endovasculares , Enfermeiros Clínicos , Humanos , Masculino , Feminino , Pandemias , COVID-19/epidemiologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Aorta Abdominal/cirurgia , Resultado do Tratamento , Fatores de Risco , Estudos Retrospectivos , Implante de Prótese Vascular/efeitos adversosRESUMO
OBJECTIVES: Attempts to reduce health inequities in England frequently prioritise some equity dimensions over others. Intersectionality highlights how different dimensions of inequity interconnect and are underpinned by historic and institutionalised power imbalances. We aimed to explore whether intersectionality could help us shed light on young adults' understanding of health inequities. STUDY DESIGN: The study incorporatedqualitative thematic analysis of primary data. METHODS: Online focus groups with young adults (n = 25) aged 18-30 living in three English regions (Greater London; South Yorkshire/Midlands; North-East England) between July 2020 and March 2021. Online semistructured interviews (n = 2) and text-based communication was conducted for participants unable to attend online groups. RESULTS: Young adults described experiencing discrimination, privilege, and power imbalances driving health inequity and suggested ways to address this. Forms of inequity included cumulative, within group, interacting, and the experience of privilege alongside marginalisation. Young adults described discrimination occurring in settings relevant to social determinants of health and said it adversely affected health and well-being. CONCLUSION: Intersectionality, with its focus on discrimination and identity, can help public health stakeholders engage with young adults on health equity. An upstream approach to improving health equity should consider multiple and intersecting forms of discrimination along with their cultural and institutional drivers.
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Equidade em Saúde , Enquadramento Interseccional , Humanos , Adulto Jovem , Grupos Focais , Desigualdades de Saúde , Disparidades nos Níveis de Saúde , Adolescente , AdultoRESUMO
This randomised study aimed to assess and compare the efficacy of treatment protocols containing levamisole, ivermectin, or moxidectin against Capillaria spp. in naturally infected European hedgehogs (Erinaceus europaeus) presented to a British wildlife rehabilitation centre. Faecal analysis, consisting of wet mount and flotation, was performed for 229 hedgehogs weighing ≥200g. Animals testing positive for Capillaria spp. (81%), excluding pregnant females, were randomly allocated a treatment protocol. Initially, hedgehogs (n = 50) received one of six 'pilot' protocols, whereas the remaining animals (n = 97) received one of three 'main' protocols. Faecal analysis was repeated on day 8 and day 12 after treatment initiation. Efficacy of each treatment was assessed based on Capillaria reduction rate (CRR), weight gain, presence of respiratory clinical signs, and outcome. Pilot protocols containing only moxidectin had a significantly lower CRR (≥28.1%) compared to those with levamisole or ivermectin (≥86.6%), whereas the main protocols containing levamisole had a significantly higher CRR (≥93.0%) compared to those containing only ivermectin (≥69.3%). Clinical parameters did not differ significantly between treatments, but animals with respiratory clinical signs at the end of the trial were significantly more likely to have lower CRR and test positive for Crenosoma striatum. C. striatum often appeared refractory to treatment, and managing these infections requires additional anthelmintic therapy. Based on the formulations and dosages trialled, moxidectin is not recommended for treating capillariosis in European hedgehogs, whereas levamisole given orally for two consecutive days at 25-35 mg/kg is suggested as the treatment of choice.
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Anti-Helmínticos , Ivermectina , Feminino , Animais , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Levamisol/uso terapêutico , Capillaria , Macrolídeos/farmacologia , Macrolídeos/uso terapêutico , Anti-Helmínticos/uso terapêutico , Ouriços , Fezes , Contagem de Ovos de ParasitasRESUMO
BACKGROUND: Study TR03 evaluated the safety and efficacy of nalbuphine ER for prurigo nodularis (PN; NCT02174419). OBJECTIVE: We conducted supplementary analyses to assess the psychometric properties of the Worst Itch Numeric Rating Scale (WI-NRS), the TR03 primary endpoint. METHODS: Study TR03 was a double-blind, placebo-controlled, phase 2 trial in PN patients with documented scores ≥5 on the WI-NRS (0 [no itch]-10 [worst itch imaginable]) on ≥5 of 7 days before baseline. Using TR03 data, the WI-NRS's psychometric properties, including reliability, validity and ability to detect change, were evaluated. A responder threshold was estimated to facilitate interpretation of WI-NRS score changes. RESULTS: Amongst 62 treated patients, improvements in mean [SD] (median) WI-NRS scores were observed between baseline (8.2 [1.21] (8.1)) and week 10 (5.8 [2.43] (6.0)). The WI-NRS had an intraclass correlation coefficient of 0.96 (95% confidence interval, 0.93-0.98) in 42 patients who had stable Itch verbal rating scale (VRS) scores from week 9-10, supporting strong test-retest reliability. Construct validity was supported, with strong correlations at week 10 with Average Itch NRS (r = 0.87) and Itch VRS single-day/weekly mean scores (r = 0.81/0.89) and moderate correlations with ItchyQoL™ total/domain scores (r = 0.41-0.43). The WI-NRS discriminated between predefined severity subgroups based on the Itch VRS and detected changes in itching severity (effect-size estimate: -2.05; standardized response mean: -1.21). An anchor-based threshold based on a two-category improvement in the single-day Itch VRS suggests a responder threshold of ≥3.8 points (~40% improvement). CONCLUSIONS: The WI-NRS demonstrates good measurement properties, supporting its use in evaluating treatment change in PN.
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Prurigo , Método Duplo-Cego , Humanos , Prurigo/diagnóstico , Prurigo/tratamento farmacológico , Prurido/diagnóstico , Prurido/tratamento farmacológico , Psicometria , Reprodutibilidade dos Testes , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Fear of disease progression (FOP) is a rational concern for women with Ovarian Cancer (OC) and depression is also common. To date there have been no randomized trials assessing the impact of psychological intervention on depression and FOP in this patient group. PATIENTS AND METHODS: Patients with primary or recurrent OC who had recently completed chemotherapy were eligible if they scored between 5 and 19 on the PHQ-9 depression and were randomized 1:1 to Intervention (3 standardized CBT-based sessions in the 6-12 weeks post-chemotherapy) or Control (standard of care). PHQ-9, FOP-Q-SF, EORTC QLQ C30 and OV28 questionnaires were then completed every 3 months for up to 2 years. The primary endpoint was change in PHQ-9 at 3 months. Secondary endpoints were change in other scores at 3 months and all scores at later timepoints. RESULTS: 182 patients registered; 107 were randomized; 54 to Intervention and 53 to Control; mean age 59 years; 75 (70%) had completed chemotherapy for primary and 32 (30%) for relapsed OC and 67 patients completed both baseline and 3-month questionnaires. Improvement in PHQ-9 was observed for patients in both study arms at three months compared to baseline but there was no significant difference in change between Intervention and Control. A significant improvement on FOP-Q-SF scores was seen in the Intervention arm, whereas for those in the Control arm FOP-Q-SF scores deteriorated at 3 months (intervention effect = -4.4 (-7.57, -1.22), p-value = 0.008). CONCLUSIONS: CBT-based psychological support provided after chemotherapy did not significantly alter the spontaneously improving trajectory of depression scores at three months but caused a significant improvement in FOP. Our findings call for the routine implementation of FOP support for ovarian cancer patients.
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Antineoplásicos/uso terapêutico , Terapia Cognitivo-Comportamental/métodos , Depressão/terapia , Medo/psicologia , Neoplasias Ovarianas/reabilitação , Idoso , Depressão/diagnóstico , Depressão/etiologia , Depressão/psicologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/psicologia , Questionário de Saúde do Paciente/estatística & dados numéricos , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Padrão de Cuidado , Resultado do TratamentoRESUMO
BACKGROUND: Failure to take medicines for diabetes as prescribed contributes to poor outcomes from the condition. Mobile phones are ubiquitous and short message service (SMS) texts have shown promise as a low-cost intervention. We tested the effectiveness of SMS-text messaging in improving outcomes in adults with type 2 diabetes. METHODS: StAR2D was a 12-month two-arm randomised trial of SMS-text messaging and usual care in Cape Town, South Africa and Lilongwe, Malawi. Messages used behaviour change theory and were developed with patients and staff. The intervention group received four messages each week. The primary outcome was change in HbA1c. Secondary outcomes were the proportion of patients who collected > 80% medication and changes in systolic blood pressure, lipids, cardiovascular risk, and the proportion of the participants reaching treatment goals. RESULTS: The trial took place between 1 October, 2016 and 1 October 2018, 1186 participants were randomised to intervention (593) and control (593) groups. 91% of participants completed follow-up. There was a reduction in HbA1c (DCCT) in both groups but not in mean change (95% CI) between groups (- 0.08% (- 0.31 to 0.16) (IFCC - 0.82 mmol/mol (- 3.44 to 1.79). There was a small but not significant increase in the proportions of participants likely to have collected 80% or more of medication (Relative risk 1.11 (0.84 to 1.47; P = 0.47). There was a significant difference between groups in change in systolic blood pressure from baseline of 3.46 mmHg (1.48 to 5.44, P = 0.001) in favour of the intervention group. The between group difference in change in 10-year risk of coronary heart disease was - 0.71% (- 1.46 to 0.04, P = 0.064). The proportion of participants meeting treatment goals in the intervention group was 36.0% and in the control group 26.8% (Relative risk 1.36 (1.13 to 1.63, P = 0.001). Participants reported many challenges to adherence despite finding messages acceptable and useful. CONCLUSIONS: Whilst SMS text messages do not lead to improved glycaemia in these low-resource settings there appeared to be an impact on blood pressure and achievement of treatment goals but the mechanisms for this are unclear. Text messages alone, may be unsuccessful unless accompanied by health system strengthening and other forms of self-management support for type 2 diabetes. TRIAL REGISTRATION: Trial registration: ISRCTN, ISRCTN70768808. Registered 1 July 2015, http://www.isrctn.com/I ISRCTN70768808.
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Telefone Celular , Diabetes Mellitus Tipo 2 , Envio de Mensagens de Texto , Adulto , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Adesão à Medicação , África do SulRESUMO
BACKGROUND: Measurement of waist circumference is used to assess abdominal fat and risk of heart disease, type 2 diabetes, cancer and stroke. It is performed in several clinical settings for health promotion and medical assessment purposes, including statutory medical assessments where results may influence decisions on fitness to work. Under the Diving at Work Regulations 1997, working divers must have an annual assessment of their fitness to dive performed by an approved medical examiner of divers (AMED), appointed by the Health and Safety Executive (HSE). The assessment includes measurement of height, weight and waist circumference, the latter used as an indicator of central adiposity and associated health risks. AIMS: To establish the practice of AMEDs in measuring waist circumference of working divers undergoing medical assessment to determine their fitness to dive. METHODS: Ninety-seven AMEDs were sent a questionnaire and asked to describe their current practice in measuring waist circumference. The response rate was 79%. The audit standard used was the consensus document published by the World Health Organization (WHO). RESULTS: Of the 77 responses, 76 were completed sufficiently to allow analysis. When the waist was measured, there was consistency in the diver's level of clothing, stage of breathing and posture for the procedure but variability in the site of measurement. Only 7/76 (9%) respondents carried out waist measurement fully in line with WHO guidance. CONCLUSIONS: The audit has identified that there is a need for guidance for AMEDs on measuring waist circumference in the statutory medical assessment of working divers.
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The use of biodiesel blends with petroleum diesel in vehicular engines demands the evaluation of the possible impacts and effects of the gases emitted from their combustion on the environment. Among studies on these questions, biomonitoring using lichens is a viable alternative, given their interactions with the elements dispersed in the atmosphere, as well as its sensitivity and capacity to retain contaminants. In this study, we analyzed the effects of gas emissions from the combustion of biodiesel mixture with petroleum diesel on Cladonia verticillaris thalli. Samples of the lichen (10 g) were exposed to the gases emitted by the exhaust of the generator engine during the combustion process of biodiesel mixtures to petroleum diesel (7% (B7), 10% (B10), 40% (B40), 50% (B50), and 70% (B70)). At 90 days after exposure, samples were analyzed for n-alkane profiles, thallus morphology, photosynthetic pigment contents, and secondary lichen metabolites (protocetraric and fumarprotocetraric acids). Sets B7 and B10 showed better resistance of the lichen to pollutants. Set B40 showed a high stress evidenced by the chain elongation of n-alkanes structure and high chlorophyll production, presenting high morphological damages when compared to the control sets, B7 and B10. The results showed significant reductions of n-alkanes profiles for mixtures with high concentrations of biodiesel (B50 and B70), as well as decreases in the chlorophyll content. These groups showed an increase in the synthesis of secondary metabolites, corroborating the hypothesis that high concentrations of biodiesel in the mixture with petroleum diesel have greater impacts on the lichen. Schematic model for demonstration of using the lichen Cladonia verticillaris as biomonitor of effects from gas emissions from the combustion of biodiesel blends with petroleum diesel by a stationary engine.
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Biocombustíveis , Líquens , Ascomicetos , Biocombustíveis/análise , Conservação dos Recursos Naturais , Monitoramento Ambiental , Gasolina/análise , Emissões de Veículos/análiseRESUMO
Most of the world's crops depend on pollinators, so declines in both managed and wild bees raise concerns about food security. However, the degree to which insect pollination is actually limiting current crop production is poorly understood, as is the role of wild species (as opposed to managed honeybees) in pollinating crops, particularly in intensive production areas. We established a nationwide study to assess the extent of pollinator limitation in seven crops at 131 locations situated across major crop-producing areas of the USA. We found that five out of seven crops showed evidence of pollinator limitation. Wild bees and honeybees provided comparable amounts of pollination for most crops, even in agriculturally intensive regions. We estimated the nationwide annual production value of wild pollinators to the seven crops we studied at over $1.5 billion; the value of wild bee pollination of all pollinator-dependent crops would be much greater. Our findings show that pollinator declines could translate directly into decreased yields or production for most of the crops studied, and that wild species contribute substantially to pollination of most study crops in major crop-producing regions.
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Agricultura , Produtos Agrícolas , Polinização , Animais , Abelhas , Abastecimento de Alimentos , Estados UnidosRESUMO
BACKGROUND AND AIMS: Pendulous flowers (due to a flexible pedicel) are a common, convergent trait of hummingbird-pollinated flowers. However, the role of flexible pedicels remains uncertain despite several functional hypotheses. Here we present and test the 'lever action hypothesis': flexible pedicels allow pendulous flowers to move upwards from all sides, pushing the stigma and anthers against the underside of the feeding hummingbird regardless of which nectary is being visited. METHODS: To test whether this lever action increased pollination success, we wired emasculated flowers of serpentine columbine, Aquilegia eximia, to prevent levering and compared pollination success of immobilized flowers with emasculated unwired and wire controls. KEY RESULTS: Seed set was significantly lower in wire-immobilized flowers than unwired control and wire control flowers. Video analysis of visits to wire-immobilized and unwired flowers demonstrated that birds contacted the stigmas and anthers of immobilized flowers less often than those of flowers with flexible pedicels. CONCLUSIONS: We conclude that flexible pedicels permit the levering of reproductive structures onto a hovering bird. Hummingbirds, as uniquely large, hovering pollinators, differ from flies or bees which are too small to cause levering of flowers while hovering. Thus, flexible pedicels may be an adaptation to hummingbird pollination, in particular due to hummingbird size. We further speculate that this mechanism is effective only in radially symmetric flowers; in contrast, zygomorphic hummingbird-pollinated flowers are usually more or less horizontally oriented rather than having pendulous flowers and flexible pedicels.
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Aquilegia , Animais , Abelhas , Aves , Flores , Polinização , ReproduçãoRESUMO
Heterogeneity in quantity and quality of resources provided in the urban matrix may mitigate adverse effects of urbanization intensity on the structure of biotic communities. To assess this we quantified the spatial variation in butterfly richness and abundance along an impervious surface gradient using three measures of urban matrix quality: floral resource availability and origin (native vs. exotic plants), tree cover, and the occurrence of remnant habitat patches. Butterfly richness and abundance were surveyed in 100 cells (500 × 500 m), selected using a random-stratified sampling design, across a continuous gradient of imperviousness in Melbourne, Australia. Sampling occurred twice during the butterfly flight season. Occurrence data were analyzed using generalized linear models at local and mesoscales. Despite high sampling completeness, we did not detect 75% of species from the regional species pool in the urban area, suggesting that urbanization has caused a large proportion of the region's butterflies to become absent or extremely rare within Melbourne's metro-area. Those species that do remain are largely very generalist in their choice of larval host plants. Butterfly species richness and abundance declined with increasing impervious surface cover and, contrary to evidence for other taxa, there was no evidence that richness peaked at intermediate levels of urbanization. Declines in abundance appeared to be more noticeable when impervious surface cover exceeded 25%, while richness declined linearly with increasing impervious surface cover. We find evidence that the quality of the urban matrix (floral resources and remnant vegetation) influenced butterfly richness and abundance although the effects were small. Total butterfly abundance responded negatively to exotic floral abundance early in the sampling season and positively to total floral abundance later in the sampling season. Butterfly species richness increased with tree cover. Negative impacts of increased urbanization intensity on butterfly species richness and abundance may be mitigated to some extent by improving the quality of the urban matrix by enhancing tree cover and the provision of floral resources, with some evidence that native plants are more effective.
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Borboletas , Animais , Austrália , Biodiversidade , Ecossistema , Plantas , UrbanizaçãoRESUMO
AIM: Lung metastases from colorectal cancer are resected in selected patients in the belief that this confers a significant survival advantage. It is generally assumed that the 5-year survival of these patients would be near zero without metastasectomy. We tested the clinical effectiveness of this practice in Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC), a randomized, controlled noninferiority trial. METHOD: Multidisciplinary teams in 14 hospitals recruited patients with resectable lung metastases into a two-arm trial. Randomization was remote and stratified according to site, with minimization for age, sex, primary cancer stage, interval since primary resection, prior liver involvement, number of metastases and carcinoembryonic antigen level. The trial management group was blind to patient allocation until after intention-to-treat analysis. RESULTS: From 2010 to 2016, 93 participants were randomized. These patients were 35-86 years of age and had between one and six lung metastases at a median of 2.7 years after colorectal cancer resection; 29% had prior liver metastasectomy. The patient groups were well matched and the characteristics of these groups were similar to those of observational studies. The median survival after metastasectomy was 3.5 (95% CI: 3.1-6.6) years compared with 3.8 (95% CI: 3.1-4.6) years for controls. The estimated unadjusted hazard ratio for death within 5 years, comparing the metastasectomy group with the control group, was 0.93 (95% CI: 0.56-1.56). Use of chemotherapy or local ablation was infrequent and similar in each group. CONCLUSION: Patients in the control group (who did not undergo lung metastasectomy) have better survival than is assumed. Survival in the metastasectomy group is comparable with the many single-arm follow-up studies. The groups were well matched with features similar to those reported in case series.
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Neoplasias Colorretais , Neoplasias Pulmonares , Metastasectomia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Humanos , Neoplasias Pulmonares/cirurgia , Estadiamento de Neoplasias , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
INTRODUCTION: The influence of aging on the clinical presentation of obstructive sleep apnea (OSA) is not well characterized in US veterans. Our aims were to (1) examine age and established predictors of sleepiness and insomnia symptoms in veterans with OSA and (2) determine if the relationship between predictors of the Epworth sleepiness scale (ESS) and insomnia severity index (ISI) depended on age. METHODS: We performed a retrospective analysis of veterans diagnosed with OSA at the Miami VA in 2014. On polysomnography (PSG) night, questionnaires were completed querying socio-demographics, insomnia (ISI), sleepiness (ESS), and self-reported sleep duration. Regression modeling was performed to explore association of variables with (1) ESS and (2) ISI. Analyses were performed in two steps: (1) variables were tested for main effects and (2) product of age and each variable found to have an association at a significance level of p < 0.10 with primary outcome were entered separately to test for interaction. RESULTS: The sample consisted of 483 veterans (93% male, age 52 ± 13 years, 41% black, 34% Hispanic). Having a regular bed partner, higher weighted medical comorbidities, chronic pain diagnosis, and shorter sleep duration were associated with ESS. Age did not moderate the relationship between these variables and ESS. Younger age, Hispanic ethnicity, higher educational level, shorter sleep duration, mood, and pain diagnoses were each associated with the ISI. Furthermore, an age-sleep duration interaction term was associated with the ISI (b = - 0.03; p = 0.005). For all participants, there was an inverse relationship between sleep duration and ISI. However, for any sleep duration, older veterans reported lower levels of insomnia than younger veterans. DISCUSSION: Older veterans with OSA may report lower ISI scores. Alternative assessment methods for comorbid insomnia among older individuals with OSA may be needed.
Assuntos
Distúrbios do Sono por Sonolência Excessiva/diagnóstico , Apneia Obstrutiva do Sono/diagnóstico , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Veteranos/estatística & dados numéricos , Adulto , Fatores Etários , Idoso , Correlação de Dados , Distúrbios do Sono por Sonolência Excessiva/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Apneia Obstrutiva do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Estados UnidosRESUMO
Shiga toxin-producing Escherichia coli is carried in the intestine of ruminant animals, and outbreaks have occurred after contact with ruminant animals or their environment. The presence of STEC virulence genes in the environment was investigated along recreational walking paths in the North West and East Anglia regions of England. In all, 720 boot sock samples from walkers' shoes were collected between April 2013 and July 2014. Multiplex PCR was used to detect E. coli based on the amplification of the uidA gene and investigate STEC-associated virulence genes eaeA, stx1 and stx2. The eaeA virulence gene was detected in 45·5% of the samples, where stx1 and/or stx2 was detected in 12·4% of samples. There was a difference between the two regions sampled, with the North West exhibiting a higher proportion of positive boot socks for stx compared to East Anglia. In univariate analysis, ground conditions, river flow and temperature were associated with positive boot socks. The detection of stx genes in the soil samples suggests that STEC is present in the English countryside and individuals may be at risk for infection after outdoor activities even if there is no direct contact with animals. SIGNIFICANCE AND IMPACT OF THE STUDY: Several outbreaks within the UK have highlighted the danger of contracting Shiga toxin-producing Escherichia coli from contact with areas recently vacated by livestock. This is more likely to occur for STEC infections compared to other zoonotic bacteria given the low infectious dose required. While studies have determined the prevalence of STEC within farms and petting zoos, determining the risk to individuals enjoying recreational outdoor activities that occur near where livestock may be present is less researched. This study describes the prevalence with which stx genes, indicative of STEC bacteria, were found in the environment in the English countryside.
Assuntos
Adesinas Bacterianas/genética , Proteínas de Escherichia coli/genética , Toxina Shiga I/genética , Toxina Shiga II/genética , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/patogenicidade , Animais , Inglaterra , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Geografia , Humanos , Gado/microbiologia , Reação em Cadeia da Polimerase Multiplex , Escherichia coli Shiga Toxigênica/isolamento & purificação , Sapatos , Virulência/genética , Fatores de Virulência/genéticaRESUMO
Epidemiological data suggest that influenza vaccination protects against all-cause mortality in chronic obstructive pulmonary disease (COPD) patients. However, recent work has suggested there is a defect in the ability of some COPD patients to mount an adequate humoral response to influenza vaccination. The aim of our study was to investigate humoral and cell-mediated vaccine responses to the seasonal trivalent influenza vaccination (TIV) in COPD subjects and healthy controls. Forty-seven subjects were enrolled into the study; 23 COPD patients, 13 age-matched healthy controls (HC ≥ 50) and 11 young healthy control subjects (YC ≤ 40). Serum and peripheral blood mononuclear cells (PBMC) were isolated pre-TIV vaccination and at days 7 and 28 and 6 months post-vaccine for haemagglutinin inhibition (HAI) titre, antigen-specific T cell and antibody-secreting cell analysis. The kinetics of the vaccine response were similar between YC, HC and COPD patients and there was no significant difference in antibody titres between these groups at 28 days post-vaccine. As we observed no disease-dependent differences in either humoral or cellular responses, we investigated if there was any association of these measures with age. H1N1 (r = -0·4253, P = 0·0036) and influenza B (r = -0·344, P = 0·0192) antibody titre at 28 days negatively correlated with age, as did H1N1-specific CD4+ T helper cells (r = -0·4276, P = 0·0034). These results suggest that age is the primary determinant of response to trivalent vaccine and that COPD is not a driver of deficient responses per se. These data support the continued use of the yearly trivalent vaccine as an adjunct to COPD disease management.
Assuntos
Imunidade Adaptativa/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , Feminino , Testes de Inibição da Hemaglutinação/métodos , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Estações do Ano , Vacinação/métodosRESUMO
Schizophrenia is a neurodevelopmental disorder that affects up to 1% of the general population. Various genes show associations with schizophrenia and a very weak nominal association with the tight junction protein, claudin-5, has previously been identified. Claudin-5 is expressed in endothelial cells forming part of the blood-brain barrier (BBB). Furthermore, schizophrenia occurs in 30% of individuals with 22q11 deletion syndrome (22q11DS), a population who are haploinsufficient for the claudin-5 gene. Here, we show that a variant in the claudin-5 gene is weakly associated with schizophrenia in 22q11DS, leading to 75% less claudin-5 being expressed in endothelial cells. We also show that targeted adeno-associated virus-mediated suppression of claudin-5 in the mouse brain results in localized BBB disruption and behavioural changes. Using an inducible 'knockdown' mouse model, we further link claudin-5 suppression with psychosis through a distinct behavioural phenotype showing impairments in learning and memory, anxiety-like behaviour and sensorimotor gating. In addition, these animals develop seizures and die after 3-4 weeks of claudin-5 suppression, reinforcing the crucial role of claudin-5 in normal neurological function. Finally, we show that anti-psychotic medications dose-dependently increase claudin-5 expression in vitro and in vivo while aberrant, discontinuous expression of claudin-5 in the brains of schizophrenic patients post mortem was observed compared to age-matched controls. Together, these data suggest that BBB disruption may be a modifying factor in the development of schizophrenia and that drugs directly targeting the BBB may offer new therapeutic opportunities for treating this disorder.