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1.
Sci Rep ; 14(1): 6201, 2024 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485959

RESUMO

Globally, pesticides improve crop yields but at great environmental cost, and their overuse has caused resistance. This incurs large financial and production losses but, despite this, very diversified farm management that might delay or prevent resistance is uncommon in intensive farming. We asked farmers to design more diversified cropping strategies aimed at controlling herbicide resistance, and estimated resulting weed densities, profits, and yields compared to prevailing practice. Where resistance is low, it is financially viable to diversify pre-emptively; however, once resistance is high, there are financial and production disincentives to adopting diverse rotations. It is therefore as important to manage resistance before it becomes widespread as it is to control it once present. The diverse rotations targeting high resistance used increased herbicide application frequency and volume, contributing to these rotations' lack of financial viability, and raising concerns about glyphosate resistance. Governments should encourage adoption of diverse rotations in areas without resistance. Where resistance is present, governments may wish to incentivise crop diversification despite the drop in wheat production as it is likely to bring environmental co-benefits. Our research suggests we need long-term, proactive, food security planning and more integrated policy-making across farming, environment, and health arenas.


Assuntos
Herbicidas , Controle de Plantas Daninhas , Controle de Plantas Daninhas/métodos , Resistência a Herbicidas , Produtos Agrícolas , Herbicidas/farmacologia , Glifosato , Agricultura/métodos , Plantas Daninhas
2.
Pest Manag Sci ; 80(7): 3172-3181, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38345468

RESUMO

BACKGROUND: Cinmethylin is an inhibitor of plant fatty acid biosynthesis, with in-plant activity caused by its binding to fatty acid thioesterases (FATs). The recent registration of cinmethylin for pre-emergence herbicidal use in the UK represents a new mode-of-action (MOA) for control of the grassweed blackgrass (Alopecurus myosuroides). To date there is little published information on the extent of blackgrass' inter-population variability in sensitivity to cinmethylin, nor on any potential effect of existing non-target-site resistance (NTSR) mechanisms on cinmethylin efficacy. RESULTS: Here we present a study of variability in cinmethylin sensitivity amongst 97 UK blackgrass populations. We demonstrate that under controlled conditions, a UK field-rate dose of 500 g ha-1 provides effective control of the tested populations. Nevertheless, we reveal significant inter-population variability at doses below this rate, with populations previously characterised as strongly NTSR displaying the lowest sensitivity to cinmethylin. Assessment of paired resistant 'R' and sensitive 'S' lines from standardised genetic backgrounds confirms that selection for NTSR to the acetyl-CoA-carboxylase inhibitor fenoxaprop, and the microtubule assembly inhibitor pendimethalin, simultaneously results in reduced sensitivity to cinmethylin at doses below 500 g ha-1. Whilst we find no resistance to the field-rate dose, we reveal that cinmethylin sensitivity can be further reduced through experimental selection with cinmethylin. CONCLUSION: Cinmethylin therefore represents a much-needed further MOA for blackgrass control, but needs to be carefully managed within a resistance monitoring and integrated weed management (IWM) framework to maximise the effective longevity of this compound. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Resistência a Herbicidas , Herbicidas , Poaceae , Herbicidas/farmacologia , Resistência a Herbicidas/genética , Poaceae/genética , Poaceae/efeitos dos fármacos
3.
BMJ Open ; 12(11): e064518, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36343992

RESUMO

OBJECTIVES: Interest in less than full-time training (LTFT) is growing among doctors in training. LTFT applications have previously been limited to fulfilment of specific criteria such as childcare or health reasons, but Health Education for England (HEE) has recently completed a pilot into LTFT for a third category: lifestyle choice. This was recognised as an opportunity to canvas trainee perspectives and intentions on LTFT and implications for workforce planning. DESIGN: A cross-sectional study of UK trainees via an online questionnaire. SETTING/PARTICIPANTS: The survey was distributed via email to trainees in all specialities and stages of training across the UK. The survey focused on three key themes: experiences of current LTFT trainees, perspectives of trainees considering LTFT in the future and experience of working with LTFT colleagues. RESULTS: Responses were received from 783 trainees across the UK, with most responses received from physician trainees (76%). Current LTFT trainees represented one-third of respondents. Of those not currently working LTFT, 75% expressed an intention to do so in future with lifestyle being the most common reason. Almost half of this group were concerned about the impact on their training. Stigma, reduced training opportunities, prolonged training and the application process were commonly cited barriers. These difficulties were experienced by several current LTFT trainees, 32% of whom described a negative impact on their training. Almost two-thirds (62%) of respondents stated they wish to work LTFT as a consultant. CONCLUSION: Systems must adapt to increase access to LTFT training to promote trainee well-being and retention. Progress is being made and we suggest HEE's category three pilot be rolled out across the UK as a priority. Workforce planning needs to consider the substantial rise in popularity of LTFT among trainees to offset any shortfalls in the present and future workforce.


Assuntos
Atitude do Pessoal de Saúde , Intenção , Humanos , Estudos Transversais , Inquéritos e Questionários , Reino Unido
4.
Clin J Am Soc Nephrol ; 17(6): 843-850, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35649718

RESUMO

BACKGROUND AND OBJECTIVES: Patients receiving hemodialysis are at high risk from coronavirus disease 2019 (COVID-19) and demonstrate impaired immune responses to vaccines. There have been several descriptions of their immunologic responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, but few studies have described the clinical efficacy of vaccination in patients on hemodialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In a multicenter observational study of the London hemodialysis population undergoing surveillance PCR testing during the period of vaccine rollout with BNT162b2 and AZD1222, all of those positive for SARS-CoV-2 were identified. Clinical outcomes were analyzed according to predictor variables, including vaccination status, using a mixed effects logistic regression model. Risk of infection was analyzed in a subgroup of the base population using a Cox proportional hazards model with vaccination status as a time-varying covariate. RESULTS: SARS-CoV-2 infection was identified in 1323 patients of different ethnicities (Asian/other, 30%; Black, 38%; and White, 32%), including 1047 (79%) unvaccinated, 86 (7%) after first-dose vaccination, and 190 (14%) after second-dose vaccination. The majority of patients had a mild course; however, 515 (39%) were hospitalized, and 172 (13%) died. Older age, diabetes, and immune suppression were associated with greater illness severity. In regression models adjusted for age, comorbidity, and time period, prior two-dose vaccination was associated with a 75% (95% confidence interval, 56 to 86) lower risk of admission and 88% (95% confidence interval, 70 to 95) fewer deaths compared with unvaccinated patients. No loss of protection was seen in patients over 65 years or with increasing time since vaccination, and no difference was seen between vaccine types. CONCLUSIONS: These data demonstrate a substantially lower risk of severe COVID-19 after vaccination in patients on dialysis who become infected with SARS-CoV-2.


Assuntos
Vacina BNT162 , COVID-19 , ChAdOx1 nCoV-19 , Diálise Renal , Vacina BNT162/administração & dosagem , COVID-19/epidemiologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19/administração & dosagem , Humanos , Londres , Estudos Prospectivos , Índice de Gravidade de Doença , Vacinação
5.
Nephrol Dial Transplant ; 37(10): 1944-1950, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-35767848

RESUMO

BACKGROUND: Hemodialysis patients are at high risk of Covid-19, though vaccination has significant efficacy in preventing and reducing the severity of infection. Little information is available on disease severity and vaccine efficacy since the dissemination of the Omicron variant. METHODS: In a multi-center study, during a period of the epidemic driven by the Omicron variant, all hemodialysis patients positive for SARS-CoV-2 were identified. Outcomes were analyzed according to predictor variables including vaccination status. Risk of infection was analyzed using a Cox proportional hazards model. RESULTS: SARS-CoV-2 infection was identified in 1126 patients including 200 (18%) unvaccinated, 56 (5%) post first dose, 433 (38%) post second dose, and 437 (39%) at least 7 days beyond their third dose. The majority of patients had a mild course but 160 (14%) were hospitalized and 28 (2%) died. In regression models adjusted for age and comorbidity, two-dose vaccination was associated with a 39% (95%CI: 2%-62%) reduction in admissions, but third doses provided additional protection, with a 51% (95%CI: 25%-69%) further reduction in admissions. Among 1265 patients at risk at the start of the observation period, SARS-CoV-2 infection was observed in 211 (17%). Two-dose vaccination was associated with a 41% (95%CI: 3%-64%) reduction in the incidence of infection, with no clear additional effect provided by third doses. CONCLUSIONS: These data demonstrate lower incidence of SARS-CoV-2 infection after vaccination in dialysis patients during an Omicron dominant period of the epidemic. Among those developing infection, severe illness was less common with prior vaccination, particularly after third vaccine doses.


Assuntos
COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos de Coortes , Humanos , Diálise Renal/efeitos adversos , SARS-CoV-2 , Vacinação
6.
Pest Manag Sci ; 78(7): 3039-3050, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35437938

RESUMO

BACKGROUND: Unravelling the genetic architecture of non-target-site resistance (NTSR) traits in weed populations can inform questions about the inheritance, trade-offs and fitness costs associated with these traits. Classical quantitative genetics approaches allow study of the genetic architecture of polygenic traits even where the genetic basis of adaptation remains unknown. These approaches have the potential to overcome some of the limitations of previous studies into the genetics and fitness of NTSR. RESULTS: Using a quantitative genetic analysis of 400 pedigreed Alopecurus myosuroides seed families from nine field-collected populations, we found strong heritability for resistance to the acetolactate synthase and acetyl CoA carboxylase inhibitors (h2  = 0.731 and 0.938, respectively), and evidence for shared additive genetic variance for resistance to these two different herbicide modes of action, rg  = 0.34 (survival), 0.38 (biomass). We find no evidence for genetic correlations between life-history traits and herbicide resistance, indicating that resistance to these two modes of action is not associated with large fitness costs in blackgrass. We do, however, demonstrate that phenotypic variation in plant flowering characteristics is heritable, h2  = 0.213 (flower height), 0.529 (flower head number), 0.449 (time to flowering) and 0.372 (time to seed shed), demonstrating the potential for adaptation to other nonchemical management practices (e.g. mowing of flowering heads) now being adopted for blackgrass control. CONCLUSION: These results highlight that quantitative genetics can provide important insight into the inheritance and genetic architecture of NTSR, and can be used alongside emerging molecular techniques to better understand the evolutionary and fitness landscape of herbicide resistance. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Acetolactato Sintase , Herbicidas , Acetil-CoA Carboxilase/genética , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Humanos , Poaceae
7.
J Appl Microbiol ; 132(5): 3915-3924, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35157342

RESUMO

AIMS: Since management of catheter-associated infections, which are generally biofilm-based, is attempted in certain patients such as older and frail patients by using a catheter lock solution (CLS), we examined the combination of N-acetyl cysteine (NAC), an antibiofilm agent, and levofloxacin, a broad-spectrum antimicrobial agent, for this purpose. METHODS AND RESULTS: Intravascular catheters were colonized with methicillin-resistant Staphylococcus epidermidis, levofloxacin-sensitive/methicillin-resistant Staph. aureus, levofloxacin-resistant/methicillin-resistant Staph. aureus, vancomycin-resistant Enterococcus, Escherichia coli, Klebsiella pneumoniae or Pseudomonas aeruginosa and treated with a CLS containing normal saline, NAC, levofloxacin or NAC plus levofloxacin (NACLEV) and then cultured to assess their antimicrobial activities. We also examined antibiofilm and antimicrobial activities of each CLS by scanning electron microscopy (SEM) and the mechanical integrity of catheters exposed to CLS. Treatment of colonized catheters with NACLEV-CLS significantly reduced colonization (p < 0.005) against all pathogens. SEM images also indicate reduction in colonization with NACLEV-CLS with considerable reduction in both visible bacteria and the associated biofilm. Mean tensile strength of catheters exposed to CLS was not significantly different compared to controls (p > 0.05). CONCLUSIONS: These in vitro results suggest that NACLEV-CLS can significantly reduce all bacterial colonization and potentially help salvage infected catheters without affecting the catheter's mechanical integrity. SIGNIFICANCE AND IMPACT OF STUDY: This study presents a novel CLS with a broad spectrum of antimicrobial activity against catheter-associated infections, particularly in long-term catheters.


Assuntos
Anti-Infecciosos , Infecções Relacionadas a Cateter , Staphylococcus aureus Resistente à Meticilina , Acetilcisteína/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/microbiologia , Infecções Relacionadas a Cateter/prevenção & controle , Catéteres/microbiologia , Escherichia coli , Humanos , Levofloxacino/farmacologia , Staphylococcus aureus
8.
Ther Adv Endocrinol Metab ; 12: 20420188211048663, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631007

RESUMO

Diabetes mellitus is the commonest cause of end-stage kidney failure worldwide and is a proven and significant risk factor for the development of cardiovascular disease. Renal impairment has a significant impact on the physiology of glucose homeostasis as it reduces tissue sensitivity to insulin and reduces insulin clearance. Renal replacement therapy itself affects glucose control: peritoneal dialysis may induce hyperglycaemia due to glucose-rich dialysate and haemodialysis often causes hypoglycaemia due to the relatively low concentration of glucose in the dialysate. Autonomic neuropathy which is common in chronic kidney disease (CKD) and diabetes increases the risk for asymptomatic hypoglycaemia. Pharmacological options for improving glycaemic control are limited due to alterations to drug metabolism. Impaired glucose tolerance and diabetes are also common in the post-kidney-transplant setting and increase the risk of graft failure and mortality. This review seeks to summarise the literature and tackle the intricacies of glycaemic management in patients with CKD who are either on maintenance haemodialysis or have received a kidney transplant. It outlines changes to glycaemic targets, monitoring of glycaemic control, the use of oral hypoglycaemic agents, the management of severe hyperglycaemia in dialysis and kidney transplantation patients.

9.
Clin J Am Soc Nephrol ; 16(8): 1237-1246, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34074636

RESUMO

BACKGROUND AND OBJECTIVES: Patients receiving in-center hemodialysis treatment face unique challenges during the coronavirus disease 2019 (COVID-19) pandemic, specifically the need to attend for treatment that prevents self-isolation. Dialysis unit attributes and isolation strategies that might reduce dialysis center COVID-19 infection rates have not been previously examined. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We explored the role of variables, including community disease burden, dialysis unit attributes (size and layout), and infection control strategies, on rates of COVID-19 among patients receiving in-center hemodialysis in London, United Kingdom, between March 2, 2020 and May 31, 2020. The two outcomes were defined as (1) a positive test for infection or admission with suspected COVID-19 and (2) admission to the hospital with suspected infection. Associations were examined using a discrete time multilevel time-to-event analysis. RESULTS: Data on 5755 patients dialyzing in 51 units were analyzed; 990 (17%) tested positive and 465 (8%) were admitted with suspected COVID-19 between March 2 and May 31, 2020. Outcomes were associated with age, diabetes, local community COVID-19 rates, and dialysis unit size. A greater number of available side rooms and the introduction of mask policies for asymptomatic patients were inversely associated with outcomes. No association was seen with sex, ethnicity, or deprivation indices, nor with any of the different isolation strategies. CONCLUSIONS: Rates of COVID-19 in the in-center hemodialysis population relate to individual factors, underlying community transmission, unit size, and layout.


Assuntos
COVID-19/etiologia , Diálise Renal , SARS-CoV-2 , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Feminino , Humanos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Risco
10.
Kidney Int Rep ; 6(3): 574-585, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33363263

RESUMO

INTRODUCTION: There is paucity of literature comparing outcomes of kidney transplant patients with COVID-19 to that of dialysis and waitlisted patients. This report describes our data, provides comparative analysis, together with a meta-analysis of published studies, and describes our protocols to restart the transplant program. METHODS: Data were analyzed on kidney transplant, dialysis, and waitlisted patients tested positive for SARS-CoV-2 (nasopharyngeal swab polymerase chain reaction [PCR] test) between March 1, 2020, and June 30, 2020, together with a meta-analysis of 16 studies. RESULTS: Twenty-three of 1494 kidney transplant patients tested positive for SARS-CoV-2 compared with 123 of 1278 hemodialysis patients (1.5% vs. 9.6%, P < 0.001) and 12 of 253 waitlisted patients (1.5% vs. 4.7%, P = 0.002). Nineteen patients required hospital admission, of whom 6 died and 13 developed AKI. The overall case fatality ratio was 26.1% compared with patients on hemodialysis (27.6%, P = 0.99) and waitlisted patients (8.3%, P = 0.38). Within our entire cohort, 0.4% of transplant patients died compared with 0.4% of waitlisted patients and 2.7% of hemodialysis patients. Patients who died were older (alive [median age 71 years] vs. dead [median age 59 years], P = 0.01).In a meta-analysis of 16 studies, including ours, the pooled case fatality ratio was 24% (95% confidence interval [CI] 19%, 28%); AKI proportion in 10 studies was 50% (95% CI 45%, 56%), with some evidence against no heterogeneity between studies (P = 0.02). CONCLUSIONS: From our cohort of transplant patients, a significantly lower proportion of patients contracted COVID-19 compared with waitlisted and dialysis patients. The case fatality ratio was comparable to that of the dialysis cohort and to a pooled case fatality ratio from a meta-analysis of 16 studies. The pooled AKI ratio in the meta-analysis was similar to our results.

11.
Nat Commun ; 11(1): 4441, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32879303

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

12.
Nat Commun ; 11(1): 3086, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32555156

RESUMO

Intense selection by pesticides and antibiotics has resulted in a global epidemic of evolved resistance. In agriculture and medicine, using mixtures of compounds from different classes is widely accepted as optimal resistance management. However, this strategy may promote the evolution of more generalist resistance mechanisms. Here we test this hypothesis at a national scale in an economically important agricultural weed: blackgrass (Alopecurus myosuroides), for which herbicide resistance is a major economic issue. Our results reveal that greater use of herbicide mixtures is associated with lower levels of specialist resistance mechanisms, but higher levels of a generalist mechanism implicated in enhanced metabolism of herbicides with diverse modes of action. Our results indicate a potential evolutionary trade-off in resistance management, whereby attempts to reduce selection for specialist resistance traits may promote the evolution of generalist resistance. We contend that where specialist and generalist resistance mechanisms co-occur, similar trade-offs will be evident, calling into question the ubiquity of resistance management based on mixtures and combination therapies.


Assuntos
Evolução Molecular , Resistência a Herbicidas , Herbicidas , Poaceae/fisiologia , Controle de Plantas Daninhas , Produtos Agrícolas/fisiologia , Ecologia , Genes de Plantas , Geografia , Mutação , Fenótipo , Plantas Daninhas/fisiologia , Sementes , Regulação para Cima
13.
BMC Nephrol ; 21(1): 92, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32160893

RESUMO

BACKGROUND: The efficacy and safety of minimisation of immunosuppression including early steroid withdrawal in kidney transplant recipients treated with Basiliximab induction remains unclear. METHODS: This retrospective cohort study reports the outcomes from 298 consecutive renal transplants performed since 1st July 2010-June 2013 treated with Basiliximab induction and early steroid withdrawal in low immunological risk patients using a simple immunological risk stratification and 3-month protocol biopsy to optimise therapy. The cohort comprised 225 low-risk patients (first transplant or HLA antibody calculated reaction frequency (CRF ≤50% with no donor specific HLA antibodies) who underwent basiliximab induction, steroid withdrawal on day 7 and maintenance with tacrolimus and mycophenolate mofetil (MMF), and 73 high-risk patients who received tacrolimus, MMF and prednisolone for the first 3 months followed by long term maintenance immunosuppression with tacrolimus and prednisolone. High-risk patients not undergoing 3-month protocol biopsy were continued on triple immunosuppression. RESULTS: Steroid withdrawal could be safely achieved in low immunological risk recipients with IL2 receptor antibody induction. The incidence of biopsy-proven acute rejection was 15.1% in the low-risk and 13.9% in the high-risk group (including sub-clinical rejection detected at protocol biopsy). One- year graft survival was 93.3% and patient survival 98.5% in the low-risk group, and 97.3 and 100% respectively in the high-risk group. Graft function was similar in each group at 1 year (mean eGFR 61.2 ± 23.4 mL/min low-risk and 64.6 ± 19.2 mL/min high-risk). CONCLUSIONS: Immunosuppression regimen comprising basiliximab induction, tacrolimus, MMF and prednisolone with early steroid withdrawal in low risk patients and MMF withdrawal in high risk patients following a normal 3-month protocol biopsy is effective in limiting acute rejection episodes and produces excellent rates of patient survival, graft function and complications.


Assuntos
Imunossupressores/administração & dosagem , Transplante de Rim , Cuidados Pós-Operatórios/métodos , Adulto , Idoso , Azatioprina/administração & dosagem , Basiliximab/administração & dosagem , Basiliximab/efeitos adversos , Esquema de Medicação , Feminino , Glucocorticoides/administração & dosagem , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Humanos , Imunossupressores/efeitos adversos , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/efeitos adversos , Infecções Oportunistas/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Prednisolona/administração & dosagem , Receptores de Interleucina-2/antagonistas & inibidores , Insuficiência Renal Crônica/cirurgia , Estudos Retrospectivos , Medição de Risco , Tacrolimo/administração & dosagem , Tacrolimo/efeitos adversos , Adulto Jovem
14.
Nat Sustain ; 3(1): 63-71, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31942455

RESUMO

Pesticides have underpinned significant improvements in global food security, albeit with associated environmental costs. Currently, the yield benefits of pesticides are threatened as overuse has led to wide-scale evolution of resistance. Yet despite this threat, there are no large-scale estimates of crop yield losses or economic costs due to resistance. Here, we combine national-scale density and resistance data for the weed Alopecurus myosuroides (black-grass) with crop yield maps and a new economic model to estimate that the annual cost of resistance in England is £0.4bn in lost gross profit (2014 prices), and annual wheat yield loss due to resistance is 0.8 million tonnes. A total loss of herbicide control against black-grass would cost £1bn and 3.4 million tonnes of lost wheat yield annually. Worldwide, there are 253 herbicide-resistant weeds, so the global impact of resistance could be enormous. Our research provides an urgent case for national-scale planning to combat further evolution of resistance, and an incentive for policies focused on increasing yields through more sustainable food-production systems rather than relying so heavily on herbicides.

15.
Kidney360 ; 1(11): 1226-1243, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-35372882

RESUMO

Background: Patients on dialysis with frequent comorbidities, advanced age, and frailty, who visit treatment facilities frequently, are perhaps more prone to SARS-CoV-2 infection and related death-the risk factors and dynamics of which are unknown. The aim of this study was to investigate the hospital outcomes in patients on dialysis infected with SARS-CoV-2. Methods: Data on 224 patients on hemodialysis between February 29, 2020 and May 15, 2020 with confirmed SARS-CoV-2 were analyzed for outcomes and potential risk factors for death, using a competing risk-regression model assessed by subdistribution hazards ratio (SHR). Results: Crude data analyses suggest an overall case-fatality ratio of 23% (95% CI, 17% to 28%) overall, but that varies across age groups from 11% (95% CI, 0.9% to 9.2%) in patients ≤50 years old and 32% (95% CI, 17% to 48%) in patients >80 years; with 60% of deaths occurring in the first 15 days and 80% within 21 days, indicating a rapid deterioration toward death after admission. Almost 90% of surviving patients were discharged within 28 days. Death was more likely than hospital discharge in patients who were more frail (WHO performance status, 3-4; SHR, 2.16 [95% CI, 1.25 to 3.74]; P=0.006), had ischemic heart disease (SHR, 2.28 [95% CI, 1.32 to 3.94]; P=0.003), cerebrovascular disease (SHR, 2.11 [95% CI, 1.20 to 3.72]; P=0.01), smoking history (SHR, 2.69 [95% CI, 1.33 to 5.45]; P=0.006), patients who were hospitalized (SHR, 10.26 [95% CI, 3.10 to 33.94]; P<0.001), and patients with high CRP (SHR, 1.35 [95% CI, 1.10 to 1.67]) and a high neutrophil:lymphocyte ratio (SHR, 1.03 [95% CI, 1.01 to 1.04], P<0.001). Our data did not support differences in the risk of death associated with sex, ethnicity, dialysis vintage, or other comorbidities. However, comparison with the entire dialysis population attending these hospitals, in which 13% were affected, revealed that patients who were non-White (62% versus 52% in all patients, P=0.001) and those with diabetes (54% versus 22%, P<0.001) were disproportionately affected. Conclusions: This report discusses the outcomes of a large cohort of patients on dialysis. We found SARS-CoV-2 infection affected more patients with diabetes and those who were non-White, with a high case-fatality ratio, which increased significantly with age, frailty, smoking, increasing CRP, and neutrophil:lymphocyte ratio at presentation.


Assuntos
COVID-19 , COVID-19/epidemiologia , Estudos de Coortes , Humanos , Londres/epidemiologia , Pessoa de Meia-Idade , Diálise Renal , SARS-CoV-2
16.
Front Plant Sci ; 10: 837, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31297127

RESUMO

The evolution of resistance to herbicides is a classic example of rapid contemporary adaptation in the face of a novel environmental stress. Evolutionary theory predicts that selection for resistance will be accompanied by fitness trade-offs in environments where the stress is absent. Alopecurus myosuroides, an autumn-germinating grass weed of cereal crops in North-West Europe, has evolved resistance to seven herbicide modes-of-action, making this an ideal species to examine the presence and magnitudes of such fitness costs. Here, we use two contrasting A. myosuroides phenotypes derived from a common genetic background, one with enhanced metabolism resistance to a commercial formulation of the sulfonylurea (ALS) actives mesosulfuron and iodosulfuron, and the other with susceptibility to these actives (S). Comparisons of plant establishment, growth, and reproductive potential were made under conditions of intraspecific competition, interspecific competition with wheat, and over a gradient of nitrogen deprivation. Herbicide dose response assays confirmed that the two lines had contrasting resistance phenotypes, with a 20-fold difference in resistance between them. Pleiotropic effects of resistance were observed during plant development, with R plants having a greater intraspecific competitive effect and longer tiller lengths than S plants during vegetative growth, but with S plants allocating proportionally more biomass to reproductive tissues during flowering. Direct evidence of a reproductive cost of resistance was evident in the nitrogen deprivation experiment with R plants producing 27% fewer seed heads per plant, and a corresponding 23% reduction in total seed head length. However, these direct effects of resistance on fecundity were not consistent across experiments. Our results demonstrate that a resistance phenotype based on enhanced herbicide metabolism has pleiotropic impacts on plant growth, development and resource partitioning but does not support the hypothesis that resistance is associated with a consistent reproductive fitness cost in this species. Given the continued difficulties associated with unequivocally detecting costs of herbicide resistance, we advocate future studies that adopt classical evolutionary quantitative genetics approaches to determine genetic correlations between resistance and fitness-related plant life history traits.

17.
Oxf Med Case Reports ; 2019(5): omz031, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31198567

RESUMO

Administration of the influenza vaccine has been associated with development of several autoimmune phenomena. We describe the case of a 72-year-old male who developed double seropositive vasculitis following seasonal influenza vaccination. On presentation, he was positive for both myeloperoxidase anti-neutrophil cytoplasmic antibody and anti-glomerular basement membrane antibody. He had stage three acute kidney injury requiring dialysis and was treated with methylprednisolone, intravenous cyclophosphamide and plasma exchange. He was also noted to have an incidental seven centimetre abdominal aortic aneurysm. He achieved remission with recovery in renal function and became haemodialysis independent. We hypothesize that the temporal relationship between influenza vaccination and double seropositive vasculitis directly triggered a systemic immune response in a susceptible patient, although a causal relationship cannot be proved. To the best of our knowledge, this is the first case of double seropositive vasculitis occurring in close temporal association with seasonal influenza vaccination.

18.
New Phytol ; 223(3): 1584-1594, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30883786

RESUMO

The evolution of resistance to herbicides is a striking example of rapid, human-directed adaptation with major consequences for food production. Most studies of herbicide resistance are performed reactively and focus on post hoc determination of resistance mechanisms following the evolution of field resistance. If the evolution of resistance can be anticipated, however, pro-active management to slow or prevent resistance traits evolving can be advocated. We report a national-scale study that combines population monitoring, glyphosate sensitivity assays, quantitative genetics and epidemiological analyses to pro-actively identify the prerequisites for adaptive evolution (directional selection and heritable genetic variation) to the world's most widely used herbicide (glyphosate) in a major, economically damaging weed species, Alopecurus myosuroides. Results highlighted pronounced, heritable variability in glyphosate sensitivity amongst UK A. myosuroides populations. We demonstrated a direct epidemiological link between historical glyphosate selection and current population-level sensitivity, and show that current field populations respond to further glyphosate selection. This study provides a novel, pro-active assessment of adaptive potential for herbicide resistance, and provides compelling evidence of directional selection for glyphosate insensitivity in advance of reports of field resistance. The epidemiological approach developed can provide a basis for further pro-active study of resistance evolution across pesticide resistance disciplines.


Assuntos
Evolução Biológica , Produtos Agrícolas/efeitos dos fármacos , Glicina/análogos & derivados , Resistência a Herbicidas , Plantas Daninhas/efeitos dos fármacos , Geografia , Glicina/toxicidade , Padrões de Herança/genética , Seleção Genética , Reino Unido , Glifosato
19.
Plant J ; 94(4): 709-720, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29575327

RESUMO

Herbicide resistance in grass weeds is now one of the greatest threats to sustainable cereal production in Northern Europe. Multiple-herbicide resistance (MHR), a poorly understood multigenic and quantitative trait, is particularly problematic as it provides tolerance to most classes of chemistries currently used for post-emergence weed control. Using a combination of transcriptomics and proteomics, the evolution of MHR in populations of the weed blackgrass (Alopecurus myosuroides) has been investigated. While over 4500 genes showed perturbation in their expression in MHR versus herbicide sensitive (HS) plants, only a small group of proteins showed >2-fold changes in abundance, with a mere eight proteins consistently associated with this class of resistance. Of the eight, orthologues of three of these proteins are also known to be associated with multiple drug resistance (MDR) in humans, suggesting a cross-phyla conservation in evolved tolerance to chemical agents. Proteomics revealed that MHR could be classified into three sub-types based on the association with resistance to herbicides with differing modes of action (MoA), being either global, specific to diverse chemistries acting on one MoA, or herbicide specific. Furthermore, the proteome of MHR plants were distinct from that of HS plants exposed to a range of biotic (insect feeding, plant-microbe interaction) and abiotic (N-limitation, osmotic, heat, herbicide safening) challenges commonly encountered in the field. It was concluded that MHR in blackgrass is a uniquely evolving trait(s), associated with changes in the proteome that are distinct from responses to conventional plant stresses, but sharing common features with MDR in humans.


Assuntos
Resistência a Herbicidas , Herbicidas/farmacologia , Proteínas de Plantas/metabolismo , Poaceae/metabolismo , Proteoma , Resistência a Múltiplos Medicamentos , Perfilação da Expressão Gênica , Proteínas de Plantas/genética , Plantas Daninhas , Poaceae/efeitos dos fármacos , Poaceae/genética , Proteômica , Estresse Fisiológico
20.
Nat Ecol Evol ; 2(3): 529-536, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29434350

RESUMO

Repeated use of xenobiotic chemicals has selected for the rapid evolution of resistance, threatening health and food security at a global scale. Strategies for preventing the evolution of resistance include cycling and mixtures of chemicals and diversification of management. We currently lack large-scale studies that evaluate the efficacy of these different strategies for minimizing the evolution of resistance. Here we use a national-scale data set of occurrence of the weed Alopecurus myosuroides (black-grass) in the United Kingdom to address this. Weed densities are correlated with assays of evolved resistance, supporting the hypothesis that resistance is driving weed abundance at a national scale. Resistance was correlated with the frequency of historical herbicide applications, suggesting that evolution of resistance is primarily driven by intensity of exposure to herbicides, but was unrelated directly to other cultural techniques. We find that populations resistant to one herbicide are likely to show resistance to multiple herbicide classes. Finally, we show that the economic costs of evolved resistance are considerable: loss of control through resistance can double the economic costs of weeds. This research highlights the importance of managing threats to food production and healthcare systems using an evolutionarily informed approach in a proactive not reactive manner.


Assuntos
Resistência a Herbicidas , Herbicidas/administração & dosagem , Plantas Daninhas/efeitos dos fármacos , Poaceae/efeitos dos fármacos , Plantas Daninhas/fisiologia , Poaceae/fisiologia , Reino Unido
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