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1.
Endoscopy ; 55(9): 847-856, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36822219

RESUMO

BACKGROUND : Assessment of competence in endoscopic retrograde cholangiopancreatography (ERCP) is critical for supporting learning and documenting attainment of skill. Validity evidence supporting ERCP observational assessment tools has not been systematically evaluated. METHODS : We conducted a systematic search using electronic databases and hand-searching from inception until August 2021 for studies evaluating observational assessment tools of ERCP performance. We used a unified validity framework to characterize validity evidence from five sources: content, response process, internal structure, relations to other variables, and consequences. Each domain was assigned a score of 0-3 (maximum score 15). We assessed educational utility and methodological quality using the Accreditation Council for Graduate Medical Education framework and the Medical Education Research Quality Instrument, respectively. RESULTS : From 2769 records, we included 17 studies evaluating 7 assessment tools. Five tools were studied for clinical ERCP, one for simulated ERCP, and one for simulated and clinical ERCP. Validity evidence scores ranged from 2 to 12. The Bethesda ERCP Skills Assessment Tool (BESAT), ERCP Direct Observation of Procedural Skills Tool (ERCP DOPS), and The Endoscopic Ultrasound (EUS) and ERCP Skills Assessment Tool (TEESAT) had the strongest validity evidence, with scores of 10, 12, and 11, respectively. Regarding educational utility, most tools were easy to use and interpret, and required minimal additional resources. Overall methodological quality (maximum score 13.5) was strong, with scores ranging from 10 to 12.5. CONCLUSIONS : The BESAT, ERCP DOPS, and TEESAT had strong validity evidence compared with other assessments. Integrating tools into training may help drive learners' development and support competency decision making.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Competência Clínica , Humanos , Avaliação Educacional/métodos , Educação de Pós-Graduação em Medicina/métodos , Curva de Aprendizado , Reprodutibilidade dos Testes
2.
Prehosp Emerg Care ; 27(5): 575-585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36066217

RESUMO

Background: Hemorrhage is a leading cause of preventable mortality from trauma, necessitating resuscitation through blood product transfusions. Early and accurate identification of patients requiring transfusions in the prehospital setting may reduce delays in time to transfusion upon arrival to hospital, reducing mortality. The purpose of this study is to characterize existing literature on predictors of transfusion and analyze their utility in the prehospital context.Objectives: The objectives of this study are to characterize the existing quantity and quality of literature regarding predictor scores for transfusion in injured patients, and to analyze the utility of predictor scores for massive transfusions in the prehospital setting and identify prehospital predictor scores for future research.Methods: A search strategy was developed in consultation with information specialists. A literature search of OVID MEDLINE from 1946 to the present was conducted for primary studies evaluating the predictive ability of scoring systems or single variables in predicting transfusion in all trauma settings.Results: Of the 5,824 studies identified, 5,784 studies underwent title and abstract screening, 94 studies underwent full text review, and 72 studies were included in the final review. We identified 16 single variables and 52 scoring systems for predicting transfusion. Among single predictor variables, fluids administered and systolic blood pressure had the highest reported sensitivity (100%) and specificity (89%) for massive transfusion protocol (MTP) activation, respectively. Among scoring systems for transfusion, the Shock Index and Modified Shock Index had the highest reported sensitivity (96%), whereas the Pre-arrival Model had the highest reported specificity (95%) for MTP activation. Overall, 20 scores were identified as applicable to the prehospital setting, 25 scores were identified as potentially applicable, and 7 scores were identified as not applicable.Conclusions: We identified an extensive list of predictive single variables, validated scoring systems, and derived models for massive transfusion, presented their properties, and identified those with potential utility in the prehospital setting. By further validating applicable scoring tools in the prehospital setting, we may begin to administer more timely transfusions in the trauma population.


Assuntos
Serviços Médicos de Emergência , Choque Hemorrágico , Ferimentos e Lesões , Humanos , Choque Hemorrágico/etiologia , Escala de Gravidade do Ferimento , Estudos Retrospectivos , Hemorragia/etiologia , Hemorragia/terapia , Ferimentos e Lesões/terapia , Ferimentos e Lesões/complicações
3.
Ann Emerg Med ; 80(5): 440-455, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35842343

RESUMO

STUDY OBJECTIVE: Machine learning models carry unique potential as decision-making aids and prediction tools for improving patient care. Traumatically injured patients provide a uniquely heterogeneous population with severe injuries that can be difficult to predict. Given the relative infancy of machine learning applications in medicine, this systematic review aimed to better understand the current state of machine learning development and implementation to help create a basis for future research. METHODS: We conducted a systematic review from inception to May 2021, using Embase, MEDLINE through Ovid, Web of Science, Google Scholar, and relevant gray literature, for uses of machine learning in predicting the outcomes of trauma patients. The screening and data extraction were performed by 2 independent reviewers. RESULTS: Of the 14,694 identified articles screened, 67 were included for data extraction. Artificial neural networks comprised the most commonly used model, and mortality was the most prevalent outcome of interest. In terms of machine learning model development, there was a lack of studies that employed external validation, feature selection methods, and performed formal calibration testing. Significant heterogeneity in reporting was also observed between the machine learning models employed, patient populations, performance metrics, and features employed. CONCLUSION: This review highlights the heterogeneity in the development and reporting of machine learning models for the prediction of trauma outcomes. While these models present an area of opportunity as an ancillary to clinical decision-making, we recommend more standardization and rigorous guidelines for the development of future models.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Humanos
4.
Glob Chang Biol ; 27(17): 4005-4023, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33942467

RESUMO

Regional long-term monitoring can enhance the detection of biodiversity declines associated with climate change, improving future projections by reducing reliance on space-for-time substitution and increasing scalability. Rodents are diverse and important consumers in drylands, regions defined by the scarcity of water that cover 45% of Earth's land surface and face increasingly drier and more variable climates. We analyzed abundance data for 22 rodent species across grassland, shrubland, ecotone, and woodland ecosystems in the southwestern USA. Two time series (1995-2006 and 2004-2013) coincided with phases of the Pacific Decadal Oscillation (PDO), which influences drought in southwestern North America. Regionally, rodent species diversity declined 20%-35%, with greater losses during the later time period. Abundance also declined regionally, but only during 2004-2013, with losses of 5% of animals captured. During the first time series (wetter climate), plant productivity outranked climate variables as the best regional predictor of rodent abundance for 70% of taxa, whereas during the second period (drier climate), climate best explained variation in abundance for 60% of taxa. Temporal dynamics in diversity and abundance differed spatially among ecosystems, with the largest declines in woodlands and shrublands of central New Mexico and Colorado. Which species were winners or losers under increasing drought and amplified interannual variability in drought depended on ecosystem type and the phase of the PDO. Fewer taxa were significant winners (18%) than losers (30%) under drought, but the identities of winners and losers differed among ecosystems for 70% of taxa. Our results suggest that the sensitivities of rodent species to climate contributed to regional declines in diversity and abundance during 1995-2013. Whether these changes portend future declines in drought-sensitive consumers in the southwestern USA will depend on the climate during the next major PDO cycle.


Assuntos
Ecossistema , Roedores , Animais , Biodiversidade , Mudança Climática , América do Norte
5.
Proc Natl Acad Sci U S A ; 114(44): E9413-E9422, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29078332

RESUMO

Here we present the genome sequence and annotation of the wild olive tree (Olea europaea var. sylvestris), called oleaster, which is considered an ancestor of cultivated olive trees. More than 50,000 protein-coding genes were predicted, a majority of which could be anchored to 23 pseudochromosomes obtained through a newly constructed genetic map. The oleaster genome contains signatures of two Oleaceae lineage-specific paleopolyploidy events, dated at ∼28 and ∼59 Mya. These events contributed to the expansion and neofunctionalization of genes and gene families that play important roles in oil biosynthesis. The functional divergence of oil biosynthesis pathway genes, such as FAD2, SACPD, EAR, and ACPTE, following duplication, has been responsible for the differential accumulation of oleic and linoleic acids produced in olive compared with sesame, a closely related oil crop. Duplicated oleaster FAD2 genes are regulated by an siRNA derived from a transposable element-rich region, leading to suppressed levels of FAD2 gene expression. Additionally, neofunctionalization of members of the SACPD gene family has led to increased expression of SACPD2, 3, 5, and 7, consequently resulting in an increased desaturation of steric acid. Taken together, decreased FAD2 expression and increased SACPD expression likely explain the accumulation of exceptionally high levels of oleic acid in olive. The oleaster genome thus provides important insights into the evolution of oil biosynthesis and will be a valuable resource for oil crop genomics.


Assuntos
Vias Biossintéticas/genética , Genoma de Planta/genética , Óleos/metabolismo , Olea/genética , Evolução Biológica , Ácidos Graxos Dessaturases/genética , Expressão Gênica/genética , Ácidos Linoleicos/genética , Olea/metabolismo , Ácido Oleico/genética , RNA Interferente Pequeno/genética
6.
Genomics ; 111(5): 997-1005, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-29679643

RESUMO

Our understanding of gene regulation is constantly evolving. It is now clear that the majority of cellular transcripts are non-coding RNAs. The spectrum of non-coding RNAs is diverse and includes short (<200 nt) and long non-coding RNAs (lncRNAs) (>200 nt). LncRNAs regulate gene expression through diverse mechanisms. In this review, we describe the emerging roles of lncRNA mediated plant gene regulation. We discuss the current classification of lncRNAs and their role in genome organization and gene regulation. We also highlight a subset of lncRNAs that are epigenetic regulators of plant gene expression. Lastly, we provide an overview of emerging techniques and databases that are employed for the identification and characterization of plant lncRNAs.


Assuntos
Magnoliopsida/genética , RNA Longo não Codificante/genética , Regulação da Expressão Gênica de Plantas , RNA Longo não Codificante/classificação , Análise de Sequência de RNA/métodos
7.
Clin Infect Dis ; 68(5): 748-756, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29982376

RESUMO

BACKGROUND: Antimicrobial stewardship programs (ASPs) using audit and feedback in the intensive care unit (ICU) setting can reduce harms related to inappropriate antibiotic use. However, inappropriate discontinuation or narrowing of antibiotic treatment could increase infection-related mortality in this population. Individual ASP studies are underpowered to detect differences in mortality. METHODS: We conducted a systematic review and meta-analysis of audit and feedback in the ICU setting, using mortality as our outcome. RESULTS: Of 2447 citations, 11 studies met our inclusion criteria. Although a variety of study designs were used to assess reductions in antibiotic use, mortality was analyzed using an uncontrolled before-after study design in all studies. Five studies directed audit and feedback to all or most ICU patients receiving antibiotics and measured overall ICU mortality. In the meta-analysis of these studies, the pooled relative risk of ICU mortality was 1.03 (95% confidence interval, .93-1.14). A second meta-analysis of 3 smaller studies that evaluated mortality only in patients directly assessed by the ASP found a pooled relative risk of ICU mortality of 1.06 (95% confidence interval, .80 to 1.4). Three studies were not appropriate for meta-analysis, but their results were consistent with our overall findings. CONCLUSIONS: Our systematic review did not identify a change in mortality associated with antimicrobial stewardship using audit and feedback in the ICU setting. These results increase our confidence that audit and feedback can be safely implemented in this setting. Future studies should report standardized estimates of mortality and use more robust study designs to assess mortality, when feasible.


Assuntos
Antibacterianos/uso terapêutico , Gestão de Antimicrobianos , Estado Terminal/mortalidade , Unidades de Terapia Intensiva , Humanos
8.
Theor Appl Genet ; 132(9): 2677-2687, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250041

RESUMO

KEY MESSAGE: Three soybean candidate genes involved in resistance to soybean cyst nematode race 4 were identified via direct whole genome re-sequencing of two segregating mutants. The genes conferring resistance to soybean cyst nematode (SCN) race 4 (Hg type 1.2.3.5.7) in soybean (Glycine max L. Merr.) remains unknown. Next generation sequencing-based methods identify a wide range of targets, it is difficult to identify genes underlying traits. Use of the MutMap and QTL-seq methods to identify trait candidate genes needs backcrossing and is very time-consuming. Here we report a simple method to effectively identify candidate genes involved in resistance to SCN race 4. Two ethane methylsulfonate mutagenized mutants of soybean 'PI 437654', whose SCN race 4-infection phenotype altered, were selected. Six relevant whole genomes were re-sequenced, and then calling of genomic variants (SNPs and InDels) was conducted and compared to 'Williams 82'. The comparison eliminated many genomic variants from the mutant lines that overlapped two non-phenotypic but mutant progeny plants, wild-type PI 437654 and 'Zhonghuang 13'. Finally, only 27 mutations were found among 10 genes. Of these 10 genes, 3 genes, Glyma.09g054000, Glyma.16g065700 and Glyma.18g192200 were overlapped between two phenotypic mutant progeny plants. Therefore, the three genes may be the candidate genes involved in resistance of PI 437654 to soybean cyst nematode race 4. This method simplifies the effective identification of candidate genes.


Assuntos
Resistência à Doença/genética , Glycine max/genética , Mutação , Doenças das Plantas/genética , Proteínas de Plantas/genética , Tylenchoidea/fisiologia , Sequenciamento Completo do Genoma/métodos , Animais , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Ligação Genética , Marcadores Genéticos , Doenças das Plantas/parasitologia , Glycine max/metabolismo , Glycine max/parasitologia
9.
Theor Appl Genet ; 131(4): 757-773, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29435603

RESUMO

KEY MESSAGE: Complexity and inconsistencies in resistance mapping publications of soybean sudden death syndrome (SDS) result in interpretation difficulty. This review integrates SDS mapping literature and proposes a new nomenclature system for reproducible SDS resistance loci. Soybean resistance to sudden death syndrome (SDS) is composed of foliar resistance to phytotoxins and root resistance to pathogen invasion. There are more than 80 quantitative trait loci (QTL) and dozens of single nucleotide polymorphisms (SNPs) associated with soybean resistance to SDS. The validity of these QTL and SNPs is questionable because of the complexity in phenotyping methodologies, the disease synergism between SDS and soybean cyst nematode (SCN), the variability from the interactions between soybean genotypes and environments, and the inconsistencies in the QTL nomenclature. This review organizes SDS mapping results and proposes the Rfv (resistance to Fusarium virguliforme) nomenclature based on supporting criteria described in the text. Among ten reproducible loci receiving our Rfv nomenclature, Rfv18-01 is mostly supported by field studies and it co-localizes to the SCN resistance locus rhg1. The possibility that Rfv18-01 is a pleiotropic resistance locus and the concern about Rfv18-01 being confounded with Rhg1 is discussed. On the other hand, Rfv06-01, Rfv06-02, Rfv09-01, Rfv13-01, and Rfv16-01 were identified both by screening soybean leaves against phytotoxic culture filtrates and by evaluating SDS severity in fields. Future phenotyping using leaf- and root-specific resistance screening methodologies may improve the precision of SDS resistance, and advanced genetic studies may further clarify the interactions among soybean genotypes, F. virguliforme, SCN, and environments. The review provides a summary of the SDS resistance literature and proposes a framework for communicating SDS resistance loci for future research considering molecular interactions and genetic breeding for soybean SDS resistance.


Assuntos
Resistência à Doença/genética , Glycine max/genética , Doenças das Plantas/genética , Fusarium , Genoma de Planta , Fenótipo , Doenças das Plantas/microbiologia , Folhas de Planta , Raízes de Plantas , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Glycine max/microbiologia
10.
Environ Res ; 164: 197-203, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29501007

RESUMO

The amount of engineered nanomaterials (ENMs) in the environment has been increasing due to their industrial and commercial applications. Different types of metallic nanoparticles (NPs) have been detected in effluents from wastewater treatment plants (WWTPs). The effluents have been reclaimed for crop irrigation in many arid and semi-arid areas. Here, a soil micro-ecosystem was established including a microbiome, 4 Arabidopsis thaliana plants, and 3 Eisenia fetida earthworms, for a duration of 95 days. The impact of wastewater effluent (WE) containing aged NPs was studied. WE was taken from a local WWTP and exhibited the presence of Ti, Ag, and Zn up to 97.0 ± 9.4, 27.4 ± 3.9, and 4.1 ± 3.6 µg/L, respectively, as well as the presence of nanoscale particles (1-100 nm in diameter). The plants were irrigated with WE or deionized water (DIW). After 95 days, significantly higher concentrations of extractable Ti and Zn (439.2 ± 24.4 and 9.0 ± 0.5 mg/kg, respectively) were found in WE-irrigated soil than those in DIW-irrigated soil (161.2 ± 2.1 and 4.0 ± 0.1 mg/kg). The extractable Ag concentrations did not differ significantly between the WE- and DIW-irrigated soil. Although microbial biomass carbon and nitrogen were not significantly reduced, the population distribution of the microbial communities was shifted in WE-irrigated soil compared to the control. The abundance of cyanobacteria (Cyanophyta) was increased by 12.5% in the WE-irrigated soil as manifested mainly by an increase of Trichodesmium spp., and the abundance of unknown archaea was enhanced from 26.7% in the control to 40.5% in the WE-irrigated soil. The biomasses of A. thaliana and E. fetida were not significantly changed by WE exposure. However, A. thaliana had a noticeable shortened life cycle, and corrected total cell fluorescence was much higher in the roots of WE-irrigated plants compared to the control. These impacts on the soil micro-ecosystem may have resulted from the aged NPs and/or the metal ions released from these NPs, as well as other components in the WE. Taken together, these results should help inform the reuse of WE containing aged NPs and other components in sustainable agriculture.


Assuntos
Arabidopsis , Microbiota , Nanopartículas , Oligoquetos , Microbiologia do Solo , Poluentes do Solo , Águas Residuárias , Animais , Solo
11.
Arch Microbiol ; 199(10): 1417-1429, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28766036

RESUMO

Spinach (Spinacia oleracea L.) leaves represent an important dietary source of nutrients, antioxidants and antimicrobials. As such, spinach leaves play an important role in health and have been used in the treatment of human diseases since ancient times. Here, the aims were to optimize the extraction methods for recovering antimicrobial substances of spinach leaves, determine the minimum inhibitory concentrations (MICs) of the antimicrobial substances against Escherichia coli and Staphylococcus aureus and, finally, evaluate the effects of spinach leaves' antimicrobials on bacterial DNA using central composite face-centered methods. The effect of the extracts on both Gram-positive and Gram-negative bacterial models was examined by scanning electron microscopy (SEM) and random amplification of polymorphic (bacterial) DNA (RAPD). The optimal extraction conditions were at 45 °C, ultrasound power of 44% and an extraction time of 23 min. The spinach extracts exhibited antimicrobial activities against both bacteria with MICs in the 60-100 mg/ml range. Interestingly, SEM showed that the treated bacterial cells appear damaged with a reduction in cell number. RAPD analysis of genomic DNA showed that the number and sizes of amplicons were decreased by treatments. Based on these results, it was inferred that spinach leaf extracts exert bactericidal activities by both inducing mutations in DNA and causing cell wall disruptions.


Assuntos
Antibacterianos/farmacologia , Escherichia coli O157/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/metabolismo , Spinacia oleracea/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica , Técnica de Amplificação ao Acaso de DNA Polimórfico
12.
Plant Biotechnol J ; 14(4): 1095-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26360509

RESUMO

Agriculture is now facing the 'perfect storm' of climate change, increasing costs of fertilizer and rising food demands from a larger and wealthier human population. These factors point to a global food deficit unless the efficiency and resilience of crop production is increased. The intensification of agriculture has focused on improving production under optimized conditions, with significant agronomic inputs. Furthermore, the intensive cultivation of a limited number of crops has drastically narrowed the number of plant species humans rely on. A new agricultural paradigm is required, reducing dependence on high inputs and increasing crop diversity, yield stability and environmental resilience. Genomics offers unprecedented opportunities to increase crop yield, quality and stability of production through advanced breeding strategies, enhancing the resilience of major crops to climate variability, and increasing the productivity and range of minor crops to diversify the food supply. Here we review the state of the art of genomic-assisted breeding for the most important staples that feed the world, and how to use and adapt such genomic tools to accelerate development of both major and minor crops with desired traits that enhance adaptation to, or mitigate the effects of climate change.


Assuntos
Produtos Agrícolas/genética , Abastecimento de Alimentos/métodos , Genômica/métodos , Melhoramento Vegetal/métodos , Mudança Climática , Variação Genética
13.
New Phytol ; 209(2): 871-84, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26479264

RESUMO

Present-day soybeans consist of elite cultivars and landraces (Glycine max, fully domesticated (FD)), annual wild type (Glycine soja, nondomesticated (ND)), and semi-wild type (semi-domesticated (SD)). FD soybean originated in China, although the details of its domestication history remain obscure. More than 500 diverse soybean accessions were sequenced using specific-locus amplified fragment sequencing (SLAF-seq) to address fundamental questions regarding soybean domestication. In total, 64,141 single nucleotide polymorphisms (SNPs) with minor allele frequencies (MAFs) > 0.05 were found among the 512 tested accessions. The results indicated that the SD group is not a hybrid between the FD and ND groups. The initial domestication region was pinpointed to central China (demarcated by the Great Wall to the north and the Qinling Mountains to the south). A total of 800 highly differentiated genetic regions and > 140 selective sweeps were identified, and these were three- and twofold more likely, respectively, to encompass a known quantitative trait locus (QTL) than the rest of the soybean genome. Forty-three potential quantitative trait nucleotides (QTNs; including 15 distinct traits) were identified by genome-wide association mapping. The results of the present study should be beneficial for soybean improvement and provide insight into the genetic architecture of traits of agronomic importance.


Assuntos
Produtos Agrícolas/genética , Domesticação , Glycine max/genética , China , Fluxo Gênico , Frequência do Gene , Genoma de Planta , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Seleção Genética
14.
Molecules ; 20(4): 6611-25, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25875040

RESUMO

The extraction of lutein and ß-carotene from spinach (Spinacia oleracea L.) leaves is important to the dietary supplement industry. A Box-Behnken design and response surface methodology (RSM) were used to investigate the effect of process variables on the ultrasound-assisted extraction (UAE) of lutein and ß-carotene from spinach. Three independent variables, extraction temperature (°C), extraction power (%) and extraction time (min) were studied. Thin-layer chromatography (TLC) followed by UV visualization and densitometry was used as a simple and rapid method for both identification and quantification of lutein and ß-carotene during UAE. Methanol extracts of leaves from spinach and authentic standards of lutein and ß-carotene were separated by normal-phase TLC with ethyl acetate-acetone (5:4 (v/v)) as the mobile phase. In this study, the combination of TLC, densitometry, and Box-Behnken with RSM methods were effective for the quantitative analysis of lutein and ß-carotene from spinach extracts. The resulting quadratic polynomial models for optimizing lutein and ß-carotene from spinach had high coefficients of determination of 0.96 and 0.94, respectively. The optimal UAE settings for output of lutein and ß-carotene simultaneously from spinach extracts were an extraction temperature of 40 °C, extraction power of 40% (28 W/cm3) and extraction time of 16 min. The identity and purity of each TLC spot was measured using time-of-flight mass spectrometry. Therefore, UAE assisted extraction of carotenes from spinach can provide a source of lutein and ß-carotene for the dietary supplement industry.


Assuntos
Fracionamento Químico/métodos , Luteína/química , Spinacia oleracea/química , Ondas Ultrassônicas , beta Caroteno/química , Cromatografia em Camada Fina , Luteína/isolamento & purificação , Espectrometria de Massas , beta Caroteno/isolamento & purificação
15.
J Sci Food Agric ; 95(11): 2237-43, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25284759

RESUMO

BACKGROUND: High temperature during grain filling affects yield, starch amylose content and activity of starch biosynthesis enzymes in basmati rice. To investigate the physiological mechanisms underpinning the effects of high temperature on rice grain, basmati rice was grown under two temperature conditions - 32 and 22 °C - during grain filling. RESULTS: High temperature decreased the grain filling period from 32 to 26 days, reducing yield by 6%, and caused a reduction in total starch (3.1%) and amylose content (22%). Measurable activities of key enzymes involved in sucrose to starch conversion, sucrose synthase, ADP-glucose pyrophosphorylase, starch phosphorylase and soluble starch synthase in endosperms developed at 32 °C were lower than those at 22 °C compared with similar ripening stage on an endosperm basis. In particular, granule-bound starch synthase (GBSS) activity was significantly lower than corresponding activity in endosperms developing at 22 °C during all developmental stages analyzed. CONCLUSION: Results suggest changes in amylose/amylopectin ratio observed in plants grown at 32 °C was attributable to a reduction in activity of GBSS, the sole enzyme responsible for amylose biosynthesis.


Assuntos
Amilose/biossíntese , Biomassa , Grão Comestível , Endosperma/enzimologia , Temperatura Alta , Oryza , Sintase do Amido/metabolismo , Amilopectina/metabolismo , Amilose/metabolismo , Metabolismo dos Carboidratos , Grão Comestível/enzimologia , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Glucosiltransferases/metabolismo , Humanos , Oryza/enzimologia , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fosforilases/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Amido/biossíntese
16.
Theor Appl Genet ; 127(12): 2525-43, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25256907

RESUMO

KEY MESSAGE: Small RNAs that are highly conserved across many plant species are involved in stress responses. Plants are exposed to many types of unfavorable conditions during their life cycle that result in some degree of stress. Recent studies on microRNAs (miRNAs) have highlighted their great potential as regulators of stress tolerance in plants. One of the possible ways in which plants counter environmental stresses is by altering their gene expression by the action of miRNAs. miRNAs regulate the expression of target genes by hybridizing to their nascent reverse complementary sequences marking them for cleavage in the nucleus or translational repression in the cytoplasm. Some miRNAs have been reported to be key regulators in biotic as well as abiotic stress responses across many species. The present review highlights some of the regulatory roles of orthologous plant miRNAs in response to various types of stress conditions.


Assuntos
MicroRNAs/genética , Fenômenos Fisiológicos Vegetais/genética , RNA de Plantas/genética , Estresse Fisiológico , Regulação da Expressão Gênica de Plantas , Plantas/genética
17.
BMC Complement Altern Med ; 14: 397, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25315352

RESUMO

BACKGROUND: Eichhornia crassipes (Mart) solms is an invasive macrophyte causing serious problems to the network of irrigation and drainage canals in the Nile Delta region. The present study aim to evaluate the potential anticancer and antioxidant activities of Eichhornia crassipes crude extract and its pure compounds. METHODS: The macrophyte was collected from El-Zomor canal, River Nile (Egypt), cleaned, air dried, grinded then extracted with methanol (crude extract). The extract was fractionated using pre-coated silica gel plates (TLC F254) with hexane/ethyl acetate (8.5: 1.5 v/v) as mobile phase. Nine fractions were separated (A-I) then scratched, eluted with the same mobile phase, filtered and the separated fractions were determined and identified using spectroscopic methods (Mass spectrum (MS), Infra red (IR) and Proton H-Nuclear magnetic resonance (H-NMR). Both the crude extract and its nine identified compounds were tested for their antioxidant (using 2, 2 diphenyl-1-picrylhydrazyl (DPPH), 2, 2'- azino-bis {ethylbenzthiazoline-6-sulfonic acid (ABTS.)} methods) and anticancer activity (using MCF-7, HeLa, Hep.G2 and EACC cell lines). RESULTS: The antioxidant and anticancer activities of the crude extract exhibited the highest effect while the compounds showed variable effects which depend on the type of compound and cancer cell line. The antioxidant activity of the crude extract exhibited the highest followed in descending order by compounds D, E, G and H respectively. Concerning the anticancer potency, the crude extract showed also the highest effect while the identified compounds (A, B, C, D, E, F, G, H and I) showed variable anticancer activities against the four different cell lines. In addition, Compound I exhibited the most potent anticancer activity against HepG2 cell line while compound D exhibited high anticancer activity against HeLa cells and EACC. The results revealed the presence of different compounds (Alkaloids and terpenoids) with variable antioxidant and anticancer activities which elicited an auto-augmentation in the crude extract leading to its greatest activities. The action of the identified anticancer compounds on DNA fragmentation was studied. CONCLUSION: The study illustrated the potential of Eichhornia as a valuable resource for natural compounds of desirable medicinal properties (e.g. antioxidants and anticancer).


Assuntos
Antioxidantes/farmacologia , Citotoxinas/farmacologia , Eichhornia/química , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Antioxidantes/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citotoxinas/química , Humanos , Neoplasias/fisiopatologia , Extratos Vegetais/química
18.
Lancet Haematol ; 11(7): e530-e539, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38937026

RESUMO

Iron deficiency is a highly prevalent condition, which contributes to unnecessary morbidity, mortality, and health inequity. A serum ferritin concentration of less than 30 µg/L has a high specificity and sensitivity for diagnosing iron deficiency in adults, but the laboratory reported lower limit of normal (LLN) is typically lower. These LLNs might not be rooted in rigorous scientific evidence and might be contributing to structural underdiagnosis of iron deficiency. A systematic review was done per systematic reviews and meta-analysis guidelines with the use of medical literature databases from inception of each database to Nov 30, 2021, to identify studies that determined ferritin reference intervals in healthy adults and grey literature search for the five most common ferritin assays (registration number CRD42022268844). The objectives were to systematically summarise the ferritin reference intervals and to do a methodological quality assessment of the included studies. 2306 studies were screened and 61 full texts were included. 37 studies were eligible for analysis of the ferritin LLN in the general population. The population the sample was comprised of was a total of 21 882 females and 23 650 males participants. The ferritin LLN was a median of 8 µg/L (IQR 5-15) and mean of 9 µg/L (SD 11) in females and a median of 25 µg/L (IQR 16-44) and mean of 25 µg/L (SD 29) in males. 30 (49%) of 61 studies did not explicitly screen for patients at risk of iron deficiency, and 32 (52%) did not refer to a reference interval establishment guideline (eg, guideline recommended by Clinical and Laboratory Standards Institute). The five most used commercial ferritin laboratory assays reported reference intervals with a median LLN of 11 (IQR 9-12) and mean of 9 µg/L (SD 4) for females and median of 22 (IQR 22-24) and mean of 23 µg/L (SD 4) for males. In the literature, serum ferritin reference intervals in healthy adults consistently report a LLN of less than 30 µg/L. Data driving these ferritin reference intervals are at high risk of bias, given no exclusion of individuals at risk for iron deficiency in the presumed normal population sample and no adherence to reference interval establishment standards. We suggest the use of evidence-based laboratory clinical decision limits to diagnose iron deficiency.


Assuntos
Ferritinas , Adulto , Feminino , Humanos , Masculino , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/sangue , Ferritinas/sangue , Valores de Referência
19.
J Cyst Fibros ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38942722

RESUMO

BACKGROUND: Data on the impact of liver transplantation (LT) in cystic fibrosis (CF) on lung function and exacerbations are limited. The objective of this study was to summarize the literature on lung function, nutritional status, survival, and complications following LT in people with CF. METHODS: Three databases were searched until September 2023, to identify the impact of LT in CF. Lung transplant prior to LT and simultaneous liver-lung transplant were excluded. Pooled hazard ratios were calculated using random-effects models. RESULTS: Thirty studies were included in this review, with 3 and 9 studies included in meta-analyses for nutritional status and lung function, respectively. Eighty-three percent of the studies used data that was more than a decade old. There was a significant increase in percent-predicted forced expiratory volume with mean change of 7.16 % (2.13, 12.19; p = 0.005) one year post-LT. Pulmonary exacerbations decreased in the short-term, however there was no significant change in body mass index (BMI). One-year survival post-LT ranged between 75 and 100 %, while five-year survival was lower at 64-89 %. CONCLUSION: Existing data suggest that LT improves lung function in the short term and does not increase the likelihood of pulmonary exacerbations, despite ongoing immunosuppression in the setting of chronic lung infection.

20.
JMIR Public Health Surveill ; 10: e40493, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236626

RESUMO

BACKGROUND: Black men who have sex with men (MSM) experience disproportionately high HIV incidence globally. A comprehensive, intersectional approach (race, gender, and sexuality or sexual behavior) in understanding the experiences of Black MSM in Canada along the HIV prevention and care continuums has yet to be explored. OBJECTIVE: This scoping review aims to examine the available evidence on the access, quality, gaps, facilitators, and barriers of engagement and identify interventions relevant to the HIV prevention and care continuum for Black MSM in Canada. METHODS: We conducted a systematic database search, in accordance with the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) checklist, of the available studies on HIV health experience and epidemiology concerning Black MSM living with or without HIV in Canada and were published after 1983 in either English or French. Searched databases include MEDLINE, Excerpta, Cumulative Index to Nursing and Allied Health Literature, the Cochrane Library, the NHUS Economic Development Database, Global Health, PsycInfo, PubMed, Scopus, and Web of Science. From the 3095 articles identified, 19 met the inclusion criteria and were analyzed. RESULTS: Black MSM in Canada consistently report multiple forms of stigma and lack of community support contributing to an increased HIV burden. They experience discrimination based on their intersectional identities while accessing HIV preventative and treatment interventions. Available data demonstrate that Black MSM have higher HIV incidences than Black men who have sex with women (MSW) and White MSM, and low preexposure prophylaxis knowledge and HIV literacy. Black MSM experience significant disparities in HIV prevention and care knowledge, access, and use. Structural barriers, including anti-Black racism, homophobia, and xenophobia, are responsible for gaps in HIV prevention and care continuums, poor quality of care and linkage to HIV services, as well as a higher incidence of HIV. CONCLUSIONS: Considering the lack of targeted interventions, there is a clear need for interventions that reduce HIV diagnoses among Black MSM, increase access and reduce structural barriers that significantly affect the ability of Black MSM to engage with HIV prevention and care, and address provider's capacity for care and the structural barriers. These findings can inform future interventions, programming, and tools that may alleviate this HIV inequity. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1136/bmjopen-2020-043055.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Humanos , Masculino , Canadá/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Comportamento Sexual , População Negra
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