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1.
Front Plant Sci ; 14: 1165056, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324675

RESUMO

Introduction: Strawberry fruit are highly valued for their aroma which develops during ripening. However, they have a short shelf-life. Low temperature storage is routinely used to extend shelf-life for transport and storage in the supply chain, however cold storage can also affect fruit aroma. Some fruit continue to ripen during chilled storage; however, strawberries are a non-climacteric fruit and hence ripening postharvest is limited. Although most strawberry fruit is sold whole, halved fruit is also used in ready to eat fresh fruit salads which are of increasing consumer demand and pose additional challenges to fresh fruit storage. Methods: To better understand the effects of cold storage, volatilomic and transcriptomic analyses were applied to halved Fragaria x ananassa cv. Elsanta fruit stored at 4 or 8°C for up to 12 days over two growing seasons. Results and discussion: The volatile organic compound (VOC) profile differed between 4 or 8°C on most days of storage. Major differences were detected between the two different years of harvest indicating that aroma change at harvest and during storage is highly dependent on environmental factors during growth. The major component of the aroma profile in both years was esters. Over 3000 genes changed in expression over 5 days of storage at 8°C in transcriptome analysis. Overall, phenylpropanoid metabolism, which may also affect VOCs, and starch metabolism were the most significantly affected pathways. Genes involved in autophagy were also differentially expressed. Expression of genes from 43 different transcription factor (TF) families changed in expression: mostly they were down-regulated but NAC and WRKY family genes were mainly up-regulated. Given the high ester representation amongst VOCs, the down-regulation of an alcohol acyl transferase (AAT) during storage is significant. A total of 113 differentially expressed genes were co-regulated with the AAT gene, including seven TFs. These may be potential AAT regulators.

2.
Cells ; 13(1)2023 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-38201249

RESUMO

Calcific aortic valve disease (CAVD) is the most common heart valve disease among aging populations. There are two reported pathways of CAVD: osteogenic and dystrophic, the latter being more prevalent. Current two-dimensional (2D) in vitro CAVD models have shed light on the disease but lack three-dimensional (3D) cell-ECM interactions, and current 3D models require osteogenic media to induce calcification. The goal of this work is to develop a 3D dystrophic calcification model. We hypothesize that, as with 2D cell-based CAVD models, programmed cell death (apoptosis) is integral to calcification. We model the cell aggregation observed in CAVD by creating porcine valvular interstitial cell spheroids in agarose microwells. Upon culture in complete growth media (DMEM with serum), calcium nodules form in the spheroids within a few days. Inhibiting apoptosis with Z-VAD significantly reduced calcification, indicating that the calcification observed in this model is dystrophic rather than osteogenic. To determine the relative roles of oxidative stress and extracellular matrix (ECM) production in the induction of apoptosis and subsequent calcification, the media was supplemented with antioxidants with differing effects on ECM formation (ascorbic acid (AA), Trolox, or Methionine). All three antioxidants significantly reduced calcification as measured by Von Kossa staining, with the percentages of calcification per area of AA, Trolox, Methionine, and the non-antioxidant-treated control on day 7 equaling 0.17%, 2.5%, 6.0%, and 7.7%, respectively. As ZVAD and AA almost entirely inhibit calcification, apoptosis does not appear to be caused by a lack of diffusion of oxygen and metabolites within the small spheroids. Further, the observation that AA treatment reduces calcification significantly more than the other antioxidants indicates that the ECM stimulatory effect of AA plays a role inhibiting apoptosis and calcification in the spheroids. We conclude that, in this 3D in vitro model, both oxidative stress and ECM production play crucial roles in dystrophic calcification and may be viable therapeutic targets for preventing CAVD.


Assuntos
Valvopatia Aórtica , Estenose da Valva Aórtica , Valva Aórtica/patologia , Calcinose , Animais , Suínos , Estresse Oxidativo , Antioxidantes/farmacologia , Apoptose , Ácido Ascórbico , Metionina , Racemetionina
3.
Front Plant Sci ; 13: 1085933, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36714770

RESUMO

Mechanisms regulating flower senescence are not fully understood in any species and are particularly complex in composite flowers. Dahlia (Dahlia pinnata Cav.) florets develop sequentially, hence each composite flower head includes florets of different developmental stages as the whole flower head ages. Moreover, the wide range of available cultivars enables assessment of intraspecific variation. Transcriptomes were compared amongst inner (younger) and outer (older) florets of two flower head ages to assess the effect of floret vs. flower head ageing. More gene expression, including ethylene and cytokinin pathway expression changed between inner and outer florets of older flower heads than between inner florets of younger and older flower heads. Additionally, based on Arabidopsis network analysis, different patterns of co-expressed ethylene response genes were elicited. This suggests that changes occur in young inner florets as the whole flower head ages that are different to ageing florets within a flower head. In some species floral senescence is orchestrated by the plant growth regulator ethylene. However, there is both inter and intra-species variation in its importance. There is a lack of conclusive data regarding ethylene sensitivity in dahlia. Speed of senescence progression, effects of ethylene signalling perturbation, and patterns of ethylene biosynthesis gene expression differed across three dahlia cultivars ('Sylvia', 'Karma Prospero' and 'Onesta') suggesting differences in the role of ethylene in their floral senescence, while effects of exogenous cytokinin were less cultivar-specific.

4.
Aging Ment Health ; 22(2): 261-269, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27768393

RESUMO

OBJECTIVE: To determine how care home managers negotiate the conflict between maintaining a safe environment while enabling the autonomy of residents with dementia. This is important because there is limited research with care home managers; yet, they are key agents in the implementation of national policies. METHOD: Semi-structured interviews were conducted with 18 managers from care homes offering dementia care in the Northwest of England. Data were analysed using a thematic analysis approach. RESULTS: There were three areas in which care home staff reported balancing safety and risk against the individual needs of residents. First, the physical environment created a tension between safety and accessibility to the outside world, which meant that care homes provided highly structured or limited access to outdoor space. Second, care home managers reflected a balancing act between an individual's autonomy and the need to protect their residents' dignity. Finally, care home managers highlighted the ways in which an individual's needs were framed by the needs of other residents to the extent that on some occasions an individual's needs were subjugated to the needs of the general population of a home. CONCLUSION: There was a strong, even dominant, ethos of risk management and keeping people safe. Managing individual needs while maintaining a safe care home environment clearly is a constant dynamic interpersonal process of negotiating and balancing competing interests for care home managers.


Assuntos
Demência , Instituição de Longa Permanência para Idosos/organização & administração , Casas de Saúde/organização & administração , Segurança do Paciente , Autonomia Pessoal , Idoso , Atitude do Pessoal de Saúde , Demência/psicologia , Demência/terapia , Inglaterra , Meio Ambiente , Feminino , Necessidades e Demandas de Serviços de Saúde , Humanos , Masculino , Gestão de Riscos/métodos , Gestão de Riscos/normas
5.
Int J Geriatr Psychiatry ; 32(12): 1205-1216, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27739182

RESUMO

OBJECTIVE: Most investigations of pharmacotherapy for treating Alzheimer's disease focus on patients with mild-to-moderate symptoms, with little evidence to guide clinical decisions when symptoms become severe. We examined whether continuing donepezil, or commencing memantine, is cost-effective for community-dwelling, moderate-to-severe Alzheimer's disease patients. METHODS: Cost-effectiveness analysis was based on a 52-week, multicentre, double-blind, placebo-controlled, factorial clinical trial. A total of 295 community-dwelling patients with moderate/severe Alzheimer's disease, already treated with donepezil, were randomised to: (i) continue donepezil; (ii) discontinue donepezil; (iii) discontinue donepezil and start memantine; or (iv) continue donepezil and start memantine. RESULTS: Continuing donepezil for 52 weeks was more cost-effective than discontinuation, considering cognition, activities of daily living and health-related quality of life. Starting memantine was more cost-effective than donepezil discontinuation. Donepezil-memantine combined is not more cost-effective than donepezil alone. CONCLUSIONS: Robust evidence is now available to inform clinical decisions and commissioning strategies so as to improve patients' lives whilst making efficient use of available resources. Clinical guidelines for treating moderate/severe Alzheimer's disease, such as those issued by NICE in England and Wales, should be revisited. © 2016 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons Ltd.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Indanos/uso terapêutico , Memantina/uso terapêutico , Piperidinas/uso terapêutico , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/economia , Inibidores da Colinesterase/economia , Cognição , Análise Custo-Benefício , Donepezila , Método Duplo-Cego , Inglaterra , Feminino , Custos de Cuidados de Saúde , Humanos , Indanos/economia , Memantina/economia , Piperidinas/economia , Qualidade de Vida , País de Gales
6.
Lancet Neurol ; 14(12): 1171-81, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26515660

RESUMO

BACKGROUND: Findings from observational studies have suggested a delay in nursing home placement with dementia drug treatment, but findings from a previous randomised trial of patients with mild-to-moderate Alzheimer's disease showed no effect. We investigated the effects of continuation or discontinuation of donepezil and starting of memantine on subsequent nursing home placement in patients with moderate-to-severe Alzheimer's disease. METHODS: In the randomised, double-blind, placebo-controlled Donepezil and Memantine in Moderate to Severe Alzheimer's Disease (DOMINO-AD) trial, community-living patients with moderate-to-severe Alzheimer's disease (who had been prescribed donepezil continuously for at least 3 months at a dose of 10 mg for at least the previous 6 weeks and had a score of between 5 and 13 on the Standardised Mini-Mental State Examination) were recruited from 15 secondary care memory centres in England and Scotland and randomly allocated to continue donepezil 10 mg per day without memantine, discontinue donepezil without memantine, discontinue donepezil and start memantine 20 mg per day, or continue donepezil 10 mg per day and start memantine 20 mg per day, for 52 weeks. After 52 weeks, choice of treatment was left to participants and their physicians. Place of residence was recorded during the first 52 weeks of the trial and then every 26 weeks for a further 3 years. A secondary outcome of the trial, reported in this study, was nursing home placement: an irreversible move from independent accommodation to a residential caring facility. Analyses restricted to risk of placement in the first year of follow-up after the patients had completed the double-blind phase of the trial were post-hoc. The DOMINO-AD trial is registered with the ISRCTN Registry, number ISRCTN49545035. FINDINGS: Between Feb 11, 2008, and March 5, 2010, 73 (25%) patients were randomly assigned to continue donepezil without memantine, 73 (25%) to discontinue donepezil without memantine, 76 (26%) to discontinue donepezil and start memantine, and 73 (25%) to continue donepezil and start memantine. 162 (55%) patients underwent nursing home placement within 4 years of randomisation, with similar numbers for all groups (36 [49%] in patients who continued donepezil without memantine, 42 [58%] who discontinued donepezil without memantine, 41 [54%] who discontinued donepezil and started memantine, and 43 [59%] who continued donepezil and started memantine). We noted significant (p=0·010) heterogeneity of treatment effect over time, with significantly more nursing home placements in the combined donepezil discontinuation groups during the first year (hazard ratio 2·09 [95% CI 1·29-3·39]) than in the combined donepezil continuation groups, and no difference during the next 3 years (0·89 [0·58-1·35]). We noted no effect of patients starting memantine compared with not starting memantine during the first year (0·92 [0·58-1·45]) or the next 3 years (1·23 [0·81-1·87]). INTERPRETATION: Withdrawal of donepezil in patients with moderate-to-severe Alzheimer's disease increased the risk of nursing home placement during 12 months of treatment, but made no difference during the following 3 years of follow-up. Decisions to stop or continue donepezil treatment should be informed by potential risks of withdrawal, even if the perceived benefits of continued treatment are not clear. FUNDING: Medical Research Council and UK Alzheimer's Society.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Instituição de Longa Permanência para Idosos , Indanos/uso terapêutico , Memantina/uso terapêutico , Nootrópicos/uso terapêutico , Casas de Saúde , Piperidinas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/enfermagem , Cognição/efeitos dos fármacos , Donepezila , Método Duplo-Cego , Feminino , Humanos , Indanos/farmacologia , Masculino , Memantina/farmacologia , Testes Neuropsicológicos , Nootrópicos/farmacologia , Piperidinas/farmacologia , Índice de Gravidade de Doença
7.
N Engl J Med ; 366(10): 893-903, 2012 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-22397651

RESUMO

BACKGROUND: Clinical trials have shown the benefits of cholinesterase inhibitors for the treatment of mild-to-moderate Alzheimer's disease. It is not known whether treatment benefits continue after the progression to moderate-to-severe disease. METHODS: We assigned 295 community-dwelling patients who had been treated with donepezil for at least 3 months and who had moderate or severe Alzheimer's disease (a score of 5 to 13 on the Standardized Mini-Mental State Examination [SMMSE, on which scores range from 0 to 30, with higher scores indicating better cognitive function]) to continue donepezil, discontinue donepezil, discontinue donepezil and start memantine, or continue donepezil and start memantine. Patients received the study treatment for 52 weeks. The coprimary outcomes were scores on the SMMSE and on the Bristol Activities of Daily Living Scale (BADLS, on which scores range from 0 to 60, with higher scores indicating greater impairment). The minimum clinically important differences were 1.4 points on the SMMSE and 3.5 points on the BADLS. RESULTS: Patients assigned to continue donepezil, as compared with those assigned to discontinue donepezil, had a score on the SMMSE that was higher by an average of 1.9 points (95% confidence interval [CI], 1.3 to 2.5) and a score on the BADLS that was lower (indicating less impairment) by 3.0 points (95% CI, 1.8 to 4.3) (P<0.001 for both comparisons). Patients assigned to receive memantine, as compared with those assigned to receive memantine placebo, had a score on the SMMSE that was an average of 1.2 points higher (95% CI, 0.6 to 1.8; P<0.001) and a score on the BADLS that was 1.5 points lower (95% CI, 0.3 to 2.8; P=0.02). The efficacy of donepezil and of memantine did not differ significantly in the presence or absence of the other. There were no significant benefits of the combination of donepezil and memantine over donepezil alone. CONCLUSIONS: In patients with moderate or severe Alzheimer's disease, continued treatment with donepezil was associated with cognitive benefits that exceeded the minimum clinically important difference and with significant functional benefits over the course of 12 months. (Funded by the U.K. Medical Research Council and the U.K. Alzheimer's Society; Current Controlled Trials number, ISRCTN49545035.).


Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Indanos/uso terapêutico , Memantina/uso terapêutico , Piperidinas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Inibidores da Colinesterase/efeitos adversos , Donepezila , Método Duplo-Cego , Sinergismo Farmacológico , Quimioterapia Combinada , Antagonistas de Aminoácidos Excitatórios/efeitos adversos , Feminino , Humanos , Indanos/efeitos adversos , Estimativa de Kaplan-Meier , Masculino , Memantina/efeitos adversos , Pacientes Desistentes do Tratamento , Piperidinas/efeitos adversos , Testes Psicológicos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Resultado do Tratamento
8.
J Mol Med (Berl) ; 90(5): 575-85, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22105852

RESUMO

Rapamycin, a specific inhibitor for mTOR complex 1, is an FDA-approved immunosuppressant for organ transplant. Recent developments have raised the prospect of using rapamycin to treat cancer or diabetes and to delay aging. It is therefore important to assess how rapamycin treatment affects glucose homeostasis. Here, we show that the same rapamycin treatment reported to extend mouse life span significantly impaired glucose homeostasis of aged mice. Moreover, rapamycin treatment of lean C57B/L6 mice reduced glucose-stimulated insulin secretion in vivo and ex vivo as well as the insulin content and beta cell mass of pancreatic islets. Confounding the diminished capacity for insulin release, rapamycin decreased insulin sensitivity. The multitude of rapamycin effects thus all lead to glucose intolerance. As our findings reveal that chronic rapamycin treatment could be diabetogenic, monitoring glucose homeostasis is crucial when using rapamycin as a therapeutic as well as experimental reagent.


Assuntos
Intolerância à Glucose/patologia , Resistência à Insulina , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Sirolimo/farmacologia , Envelhecimento/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glucose/farmacologia , Intolerância à Glucose/complicações , Homeostase/efeitos dos fármacos , Hiperglicemia/complicações , Hiperglicemia/patologia , Injeções Intraperitoneais , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/patologia , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sirolimo/administração & dosagem
9.
Neuron ; 72(4): 630-42, 2011 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-22099464

RESUMO

How transmitter receptors modulate neuronal signaling by regulating voltage-gated ion channel expression remains an open question. Here we report dendritic localization of mRNA of Kv4.2 voltage-gated potassium channel, which regulates synaptic plasticity, and its local translational regulation by fragile X mental retardation protein (FMRP) linked to fragile X syndrome (FXS), the most common heritable mental retardation. FMRP suppression of Kv4.2 is revealed by elevation of Kv4.2 in neurons from fmr1 knockout (KO) mice and in neurons expressing Kv4.2-3'UTR that binds FMRP. Moreover, treating hippocampal slices from fmr1 KO mice with Kv4 channel blocker restores long-term potentiation induced by moderate stimuli. Surprisingly, recovery of Kv4.2 after N-methyl-D-aspartate receptor (NMDAR)-induced degradation also requires FMRP, likely due to NMDAR-induced FMRP dephosphorylation, which turns off FMRP suppression of Kv4.2. Our study of FMRP regulation of Kv4.2 deepens our knowledge of NMDAR signaling and reveals a FMRP target of potential relevance to FXS.


Assuntos
Dendritos/fisiologia , Proteína do X Frágil da Deficiência Intelectual/fisiologia , Canais de Potássio Shal/fisiologia , Animais , Células Cultivadas , Células HEK293 , Humanos , Potenciação de Longa Duração/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Canais de Potássio Shal/antagonistas & inibidores
10.
Int J Geriatr Psychiatry ; 26(8): 812-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20848576

RESUMO

BACKGROUND: Although less likely to be reported in clinical trials than expressions of the statistical significance of differences in outcomes, whether or not a treatment has delivered a specified minimum clinically important difference (MCID) is also relevant to patients and their caregivers and doctors. Many dementia treatment randomised controlled trials (RCTs) have not reported MCIDs and, where they have been done, observed differences have not reached these. METHODS: As part of the development of the Statistical Analysis Plan for the DOMINO trial, investigators met to consider expert opinion- and distribution-based values for the MCID and triangulated these to provide appropriate values for three outcome measures, the Standardised Mini-mental State Examination (sMMSE), Bristol Activities of Daily Living Scale (BADLS) and Neuropsychiatric Inventory (NPI). Only standard deviations (SD) were presented to investigators who remained blind to treatment allocation. RESULTS: Adoption of values for MCIDs based upon 0.4 of the SD of the change in score from baseline on the sMMSE, BADLS and NPI in the first 127 participants to complete DOMINO yielded MCIDs of 1.4 points for sMMSE, 3.5 for BADLS and 8.0 for NPI. CONCLUSIONS: Reference to MCIDs is important for the full interpretation of the results of dementia trials and those conducting such trials should be open about the way in which they have determined and chosen their values for the MCIDs.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Interpretação Estatística de Dados , Dopaminérgicos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Atividades Cotidianas , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Tomada de Decisões , Donepezila , Humanos , Indanos/uso terapêutico , Memantina/uso terapêutico , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Piperidinas/uso terapêutico , Escalas de Graduação Psiquiátrica
11.
Trials ; 10: 57, 2009 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-19630974

RESUMO

BACKGROUND: Alzheimer's disease (AD) is the commonest cause of dementia. Cholinesterase inhibitors, such as donepezil, are the drug class with the best evidence of efficacy, licensed for mild to moderate AD, while the glutamate antagonist memantine has been widely prescribed, often in the later stages of AD. Memantine is licensed for moderate to severe dementia in AD but is not recommended by the England and Wales National Institute for Health and Clinical Excellence. However, there is little evidence to guide clinicians as to what to prescribe as AD advances; in particular, what to do as the condition progresses from moderate to severe. Options include continuing cholinesterase inhibitors irrespective of decline, adding memantine to cholinesterase inhibitors, or prescribing memantine instead of cholinesterase inhibitors. The aim of this trial is to establish the most effective drug option for people with AD who are progressing from moderate to severe dementia despite treatment with donepezil. METHOD: DOMINO-AD is a pragmatic, 15 centre, double-blind, randomized, placebo controlled trial. Patients with AD, currently living at home, receiving donepezil 10 mg daily, and with Standardized Mini-Mental State Examination (SMMSE) scores between 5 and 13 are being recruited. Each is randomized to one of four treatment options: continuation of donepezil with memantine placebo added; switch to memantine with donepezil placebo added; donepezil and memantine together; or donepezil placebo with memantine placebo. 800 participants are being recruited and treatment continues for one year. Primary outcome measures are cognition (SMMSE) and activities of daily living (Bristol Activities of Daily Living Scale). Secondary outcomes are non-cognitive dementia symptoms (Neuropsychiatric Inventory), health related quality of life (EQ-5D and DEMQOL-proxy), carer burden (General Health Questionnaire-12), cost effectiveness (using Client Service Receipt Inventory) and institutionalization. These outcomes are assessed at baseline, 6, 18, 30 and 52 weeks. All participants will be subsequently followed for 3 years by telephone interview to record institutionalization. DISCUSSION: There is considerable debate about the clinical and cost effectiveness of anti-dementia drugs. DOMINO-AD seeks to provide clear evidence on the best treatment strategies for those managing patients at a particularly important clinical transition point. TRIAL REGISTRATION: Current controlled trials ISRCTN49545035.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Dopaminérgicos/uso terapêutico , Indanos/uso terapêutico , Memantina/uso terapêutico , Nootrópicos/uso terapêutico , Piperidinas/uso terapêutico , Donepezila , Medicina Baseada em Evidências , Humanos , Projetos de Pesquisa , Índice de Gravidade de Doença
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