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1.
Heliyon ; 10(3): e25221, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38356544

RESUMO

World tree nut production has increased rapidly by around 50 % in the past decade; however, nut defects cause losses. For example, we know that brown centres are a major internal discolouration defect in macadamia nuts and are linked to the storage of nut-in-shell under improper conditions at high temperature and humidity. However, key chemical changes in brown centre kernels have not been described. In this study, we compared brown centres and white kernels from: 1) samples that were "induced" in the laboratory by storing at high moisture concentration; and 2) samples that were dried immediately after harvest using industry best practice methods recommended by the Australian Macadamia Society (AMS). We measured the moisture concentration, sugar concentration, fatty acid concentration, peroxide value, nutrient concentration and volatile compounds of induced and AMS samples. Our results showed that storing nut-in-shell macadamia under wet and hot conditions increased brown centres compared with samples immediately dried using the AMS regime, 10.33 % vs 1.44 %, respectively. Induced brown centres had significantly higher moisture concentrations than induced white centres. Volatile compounds including nonanoic acid, octanoic acid and 2,3 butanediol were identified and associated with brown centre formation in macadamia kernels and the initiation of lipid oxidation. Our results suggest sugar hydrolysis and the Maillard reaction are associated with brown centres both in laboratory induced samples and those formed using industry best practice drying methods. Our study suggests improper drying and storage at high temperature and high humidity are likely to result in brown centre formation. We recommend brown centre losses can be reduced by appropriate drying and storage practices.

2.
Front Oncol ; 13: 1268977, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023205

RESUMO

While many factors have been implicated in breast cancer progression, effective treatments are still lacking. In recent years, it has become clear that posttranscriptional regulation plays a key role in the aberrant gene expression underlying malignancy and metastasis. For example, the mRNA modification N6-methyladenosine (m6A) is involved in numerous post-transcriptional regulation processes and has been implicated in many cancer types, including breast cancer. Despite intense study, even within a single type of cancer, there is little consensus, and often conflicting results, as to the role of m6A, suggesting other factors must influence the process. The goal of this study was to determine if the effects of m6A manipulation on proliferation and migration differed based on the stage of disease progression. Using the MCF10 model of breast cancer, we reduced m6A levels by targeting METTL3, the main cellular m6A RNA methyltransferase. Knocking down Mettl3 at different stages of breast cancer progression indeed shows unique effects at each stage. The early-stage breast cancer line showed a more proliferative phenotype with the knockdown of Mettl3 while the transformed breast cancer line showed a more migratory phenotype. Interestingly, the metastasized breast cancer cell line showed almost no effect on phenotype with the knockdown of Mettl3. Furthermore, transcriptome wide analysis revealed EMT as the probable pathway influencing the phenotypic changes. The results of this study may begin to address the controversy of m6A's role in cancer and suggest that m6A may have a dynamic role in cancer that depends on the stage of progression.

3.
Pharmaceutics ; 15(8)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37631237

RESUMO

Circadian rhythms are internal manifestations of the 24-h solar day that allow for synchronization of biological and behavioral processes to the external solar day. This precise regulation of physiology and behavior improves adaptive function and survival. Chronotherapy takes advantage of circadian rhythms in physiological processes to optimize the timing of drug administration to achieve maximal therapeutic efficacy and minimize negative side effects. Chronotherapy for cancer treatment was first demonstrated to be beneficial more than five decades ago and has favorable effects across diverse cancer types. However, implementation of chronotherapy in clinic remains limited. The present review examines the evidence for chronotherapeutic treatment for solid tumors. Specifically, studies examining chrono-chemotherapy, chrono-radiotherapy, and alternative chronotherapeutics (e.g., hormone therapy, TKIs, antiangiogenic therapy, immunotherapy) are discussed. In addition, we propose areas of needed research and identify challenges in the field that remain to be addressed.

4.
Methods Mol Biol ; 2298: 171-184, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34085245

RESUMO

2'-O-methylation (Nm) is an RNA modification commonly found on rRNA and snRNA, and at the mRNA 5'-cap, but has more recently been found internally on mRNA. The study of internal Nm modifications on mRNA is in the early stages, but we have reported that this sort of Nm modification can regulate mRNA abundance and translation. Although there are many methods to determine the presence of Nm on rRNA, detecting Nm on specific mRNA transcripts is technically difficult because they are much less abundant than rRNA. Some of these methods rely on the fact that Nm modification of RNA disrupts reverse transcription reactions when performed at low dNTP concentrations. In this chapter, we describe our approach to using quantitative PCR in conjunction with reverse transcription at low dNTPs, which is sensitive enough to detect changes to Nm modification of mRNA.


Assuntos
RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Linhagem Celular , Células HEK293 , Humanos , Metilação , RNA/genética , RNA Ribossômico/genética , RNA Nuclear Pequeno/genética , Transcrição Reversa/genética
5.
BMJ Open ; 11(2): e041318, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33550240

RESUMO

INTRODUCTION: Dementia is a public health issue and a major risk factor for poor quality of life among older adults. In the absence of a cure, enhancing health-related quality of life (HRQoL) of people with dementia is the primary goal of care. Robust measurement of HRQoL is a prerequisite to effective improvement. The DEMQOL suite of instruments is considered among the best available to measure HRQoL in people with dementia; however, no review has systematically and comprehensively examined the use of the DEMQOL in research and summarised evidence to determine its feasibility, acceptability and appropriateness for use in research and practice. METHODS AND ANALYSIS: We will systematically search 12 electronic databases and reference lists of all included studies. We will include systematically conducted reviews, as well as, quantitative and qualitative research studies that report on the development, validation or use in research studies of any of the DEMQOL instruments. Two reviewers will independently screen all studies for eligibility, and assess the quality of each included study using one of four validated checklists appropriate for different study designs. Discrepancies at all stages of the review will be resolved by consensus. We will use descriptive statistics (frequencies, proportions, ranges), content analysis of narrative data and vote counting (for the measures of association) to summarise the data elements. Using narrative synthesis, we will summarise what is known about the development, validation, feasibility, acceptability, appropriateness and use of the DEMQOL. Our review methods will follow the reporting and conduct guidelines of the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. ETHICS AND DISSEMINATION: Ethical approval is not required as this project does not involve primary data collection. We will disseminate our findings through peer-reviewed publications and conference presentations. PROSPERO REGISTRATION NUMBER: CRD42020157851.


Assuntos
Qualidade de Vida , Projetos de Pesquisa , Lista de Checagem , Consenso , Metanálise como Assunto , Psicometria
6.
Rural Remote Health ; 20(4): 6112, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33035426

RESUMO

INTRODUCTION: Nav-CARE (Navigation: Connecting, Accessing, Resourcing and Engaging) is an evidence-based program that was implemented over 1 year in a rural community in western Canada. Nav-CARE uses volunteers who are trained in navigation to facilitate access to resources and provide social support to older persons living in the community with serious illness such as cancer, congestive heart failure and chronic obstructive pulmonary disease. Following implementation in which Nav-CARE was found to be feasible, acceptable and have positive outcomes, Nav-CARE was integrated into the local community-based hospice society program. Two years after a successful implementation, it continued to be sustainable in this same rural community. The purpose of this study was to explore the key factors that facilitated the sustainability of Nav-CARE in a rural hospice society. METHODS: A qualitative single case study design was used with data from several sources collected at different times: (a) pre-implementation, (b) Nav-CARE program implementation (1-year time period), (c) immediately after implementation and (d) 6 months to 2 years after implementation). Data included individual interviews with community stakeholders (n=9), the study volunteer coordinator (n=1), hospice society coordinator (n=1) and Nav-CARE volunteers (n=9). It also included meeting notes of volunteer debriefing sessions and meetings with stakeholders planning for sustainability of Nav-CARE that were held during the 1-year implementation. Data were organized using the i-PARIHS (integrated Promoting Action on Research Implementation in Health Services) framework (a well known implementation framework). Data were analyzed using Yin's qualitative case study approach. RESULTS: The findings from this case study suggested that key factors in facilitating sustainability of a rural community intervention (Nav-CARE) were the organizational context (inner context) and facilitation (facilitator and facilitation processes). Additionally, the inner context included the fit of Nav-CARE with the organization's priorities, the absorptive capacity of the organization, and organizational structure and mechanisms to integrate Nav-CARE into current programs. The hospice society was well established and supported by the rural community. The role of the facilitator and the planned facilitation processes (training of volunteer navigators, ongoing support and planning events) were key factors in the sustainability of the Nav-CARE program. The findings found that the formal role of the facilitator in the implementation and sustainability of Nav-CARE in this rural community required skills and knowledge, as well as ongoing mentorship. As well, the facilitation process for Nav-CARE included formal sustainability planning meetings involving stakeholders. CONCLUSION: Using the i-PARIHS framework and a case study approach, key factors for facilitating sustainability were identified. The role of the facilitator, the facilitation processes and the characteristics of the organizational context were important for the sustainability of Nav-CARE. Future research is needed to understand how to assess and enhance an organization's sustainability capacity and the impact of additional facilitator training and mentoring. This study provides a foundation for future research and adds to the discussion of the issue of sustainability of evidence-based interventions in rural community settings.


Assuntos
População Rural , Voluntários , Idoso , Idoso de 80 Anos ou mais , Canadá , Humanos , Avaliação de Programas e Projetos de Saúde , Pesquisa Qualitativa , Apoio Social
7.
Nat Commun ; 10(1): 3401, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31363086

RESUMO

Epitranscriptomic modifications of mRNA are important regulators of gene expression. While internal 2'-O-methylation (Nm) has been discovered on mRNA, questions remain about its origin and function in cells and organisms. Here, we show that internal Nm modification can be guided by small nucleolar RNAs (snoRNAs), and that these Nm sites can regulate mRNA and protein expression. Specifically, two box C/D snoRNAs (SNORDs) and the 2'-O-methyltransferase fibrillarin lead to Nm modification in the protein-coding region of peroxidasin (Pxdn). The presence of Nm modification increases Pxdn mRNA expression but inhibits its translation, regulating PXDN protein expression and enzyme activity both in vitro and in vivo. Our findings support a model in which snoRNA-guided Nm modifications of mRNA can regulate physiologic gene expression by altering mRNA levels and tuning protein translation.


Assuntos
Proteínas da Matriz Extracelular/genética , Peroxidase/genética , RNA Mensageiro/genética , RNA Nucleolar Pequeno/genética , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Humanos , Metilação , Metiltransferases/metabolismo , Peroxidase/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , RNA Nucleolar Pequeno/metabolismo , Peroxidasina
8.
Front Cell Neurosci ; 12: 127, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867360

RESUMO

Neurotransmitter is released from presynaptic nerve terminals at fast-transmitting synapses by the action potential-gating of voltage dependent calcium channels (CaV), primarily of the CaV2.1 and CaV2.2 types. Entering Ca2+ diffuses to a nearby calcium sensor associated with a docked synaptic vesicle (SV) and initiates its fusion and discharge. Our previous findings that single CaVs can gate SV fusion argued for one or more tethers linking CaVs to docked SVs but the molecular nature of these tethers have not been established. We recently developed a cell-free, in vitro biochemical assay, termed SV pull-down (SV-PD), to test for SV binding proteins and used this to demonstrate that CaV2.2 or the distal third of its C-terminal can capture SVs. In subsequent reports we identified the binding site and characterized an SV binding motif. In this study, we set out to test if a similar SV-binding mechanism exists in the primary presynaptic channel type, CaV2.1. We cloned the chick variant of this channel and to our surprise found that it lacked the terminal third of the C-terminal, ruling out direct correlation with CaV2.2. We used SV-PD to identify an SV binding site in the distal half of the CaV2.1 C-terminal, a region that corresponds to the central third of the CaV2.2 C-terminal. Mutant fusion proteins combined with motif-blocking peptide strategies identified two domains that could account for SV binding; one in an alternatively spliced region (E44) and a second more distal site. Our findings provide a molecular basis for CaV2.1 SV binding that can account for recent evidence of C-terminal-dependent transmitter release modulation and that may contribute to SV tethering within the CaV2.1 single channel Ca2+ domain.

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