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1.
Health Info Libr J ; 41(1): 76-83, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37574776

RESUMEN

BACKGROUND: Latin American and Caribbean Health Sciences Literature (LILACS) is the main reference database in the region; however, the way in which this resource is used in Cochrane systematic reviews has not been studied. OBJECTIVES: To assess the search methods of Cochrane reviews that used LILACS as a source of information and explore the Cochrane community's perceptions about this resource. METHODS: We identified all Cochrane reviews of interventions published during 2019, which included LILACS as a source of information, and analysed their search methods and also ran a survey through the Cochrane Community. RESULTS: We found 133 Cochrane reviews that reported the full search strategies, identifying heterogeneity in search details. The respondents to our survey highlighted many areas for improvement in the use of LILACS, including the usability of the search platform for this purpose. DISCUSSION: The use and reporting of LILACS in Cochrane reviews demonstrate inconsistencies, as evidenced by the analysis of search reports from systematic reviews and surveys conducted among members of the Cochrane community. CONCLUSION: With better guidance on how LILACS database is structured, information specialists working on Cochrane reviews should be able to make more effective use of this unique resource.


Asunto(s)
Servicios de Información , Medicina , Humanos , Publicaciones , Encuestas y Cuestionarios
2.
Environ Geochem Health ; 45(12): 9891-9901, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37882916

RESUMEN

Exposure to heavy metals may cause the overproduction of reactive oxygen species, generating oxidative stress and consequently, various harms to human health. The soil surrounding the Ventanas Industrial Complex, in Puchuncaví and Quintero municipal districts on the central Chilean coast, contains heavy metal concentrations (As, Cu, Pb, Zn, among others) that far exceed the maximum permissible levels established by Italian soil standards (used as a reference). This study aimed to investigate the potential association between heavy metal exposure in humans and the levels of oxidative stress biomarkers in inhabitants of these locations. We took blood samples from 140 adults living in sites with high concentrations of heavy metals in the soil and compared them with blood samples from 140 adults living in areas with normal heavy metal concentrations. We assessed lipid peroxidation, damage to genetic material, and Total Antioxidant Capacity in these blood samples. Our results indicate an association between oxidative damage and heavy metal exposure, where the inhabitants living in exposed areas have a higher level of DNA damage compared with those living in control areas. Given that DNA damage is one of the main factors in carcinogenesis, these results are of interest, both for public health and for public policies aimed at limiting human exposure to environmental pollution.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Adulto , Humanos , Chile , Monitoreo del Ambiente/métodos , Metales Pesados/toxicidad , Metales Pesados/análisis , Estrés Oxidativo , Suelo , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Medición de Riesgo , China
3.
J Clin Epidemiol ; 159: 31-39, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37164290

RESUMEN

OBJECTIVES: Overlap of primary studies is a key methodological challenge for overviews. There are limited reports of methods used to address overlap, and there is no detailed assessment of the corrected covered area (CCA) of a representative sample of overviews. To describe the approaches used to address overlap, and to estimate the overall and pairwise CCA. METHODS: We searched PubMed for overviews published in 2018. Two authors conducted the screening process. We described the strategy used for assessing overlap, and calculated overall and pairwise CCA for each overview. RESULTS: We analyzed a random sample of 30 out of 89 eligible articles. Eleven did not address the overlap. Of the remainder, most frequent strategies were visual assessment and discussion of overlap as a limitation. Median overall CCA among the included overviews was 6.7%. The pairwise analysis showed that 52.8% of SR pairs had slight overlap, while 28.3% had very high overlap. CONCLUSION: Reported strategies for addressing overlap vary considerably among overview authors. The pairwise approach for assessing the CCA revealed highly overlapped pairs of SRs in overviews with overall slight overlap and vice versa. We encourage authors to complement the overall CCA assessment with a pairwise approach.


Asunto(s)
Publicaciones , Proyectos de Investigación , Humanos
4.
BMJ Evid Based Med ; 28(4): 273-282, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-35217568

RESUMEN

OBJECTIVE: To assess the effectiveness of non-pharmacological interventions for the treatment of autism spectrum disorder (ASD) in children. DESIGN: Overview of systematic reviews (SRs). PARTICIPANTS: Children aged 12 years and under with ASD. SEARCH METHODS: In October 2021, we searched Cochrane Central Register of Controlled Trials, MEDLINE, Embase, PsycINFO and Epistemonikos placing no restrictions on language or date of publication. INTERVENTIONS: 17 non-pharmacological interventions compared with placebo, no-treatment (including waiting list) or other interventions (ie, usual care, as defined by the authors of each study). DATA COLLECTION AND ANALYSIS: We rated the methodological quality of the included SRs using A Measurement Tool to Assess Systematic Reviews (AMSTAR 2). We reported the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) certainty of the evidence (CoE) according to the analysis conducted by the authors of the included SRs. MAIN OUTCOME MEASURES: A multidisciplinary group of experts agreed on analysing nine critical outcomes evolving core and non-core ASD symptoms. PUBLIC AND PATIENT INVOLVEMENT STATEMENT: Organisations of parents of children with ASD participated in external revision of the final version of the report. RESULTS: We identified 52 reports that were within our scope, of which 48 were excluded for various reasons. After excluding less reliable SRs, we included four SRs. Non-pharmacological interventions (ie, Early Intensive Behavioural Intervention, Applied Behaviour Analysis, Picture Exchange Communication System and Naturalistic Developmental Behavioural Interventions) may have favourable effects on some core outcomes including language, social and functioning, play or daily living skills in children with ASD (with either no GRADE assessment, very low or low CoE). In addition, we identified a lack of report for other key outcomes in the included SRs (ie, restricted, repetitive behaviour; play and sensory processing). CONCLUSIONS: Synthesised evidence regarding the efficacy of non-pharmacological interventions for children with ASD is scarce. High-quality SRs addressing the variety of both non-pharmacological interventions and relevant outcomes are needed. PROSPERO REGISTRATION NUMBER: CRD42020206535.


Asunto(s)
Trastorno del Espectro Autista , Humanos , Niño , Trastorno del Espectro Autista/terapia , Revisiones Sistemáticas como Asunto
5.
BMJ Evid Based Med ; 28(1): 7-14, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35101925

RESUMEN

OBJECTIVES: To assess the effectiveness and safety of risperidone and aripiprazole in children with autism spectrum disorder (ASD). DESIGN AND SETTING: Overview of systematic reviews (SRs). SEARCH METHODS: In October 2021, we searched Cochrane Central Register of Controlled Trials, MEDLINE, Embase, PsycInfo and Epistemonikos placing no restrictions on language or date of publication. PARTICIPANTS: Children aged 12 years or less with ASD. INTERVENTIONS: Risperidone and aripiprazole with no dosage restrictions. DATA COLLECTION AND ANALYSIS: We rated the methodological quality of the included SRs using A Measurement Tool to Assess Systematic Reviews (AMSTAR 2). We reported the Grading of Recommendations, Assessment, Development and Evaluation certainty of the evidence according to the analysis conducted by the authors of the included SRs. MAIN OUTCOMES MEASURED: A multidisciplinary group of experts agreed on analysing nine critical outcomes evolving core and non-core ASD symptoms. PATIENT AND PUBLIC INVOLVEMENT: Organisations of parents of children with ASD were involved during part of the process, participating in external revision of the final version of the report for the Chilean Ministry of Health with no additional comments (ID 757-22-L120 DIPRECE, Ministry of Health, Chile). The organisations involved were: Fundación Unión Autismo y Neurodiversidad, Federación Nacional de Autismo, Vocería Autismo del Sur, and Vocería Autismo del Norte. RESULTS: We identified 22 SRs within the scope of this overview, of which 16 were of critically low confidence according to AMSTAR 2 and were excluded from the analysis. Both aripiprazole and risperidone were effective for reducing autism symptoms severity, repetitive behaviours, inappropriate language, social withdrawal and behavioural problems compared with placebo. The certainty of the evidence for most outcomes was moderate. Risperidone and aripiprazole are associated with metabolic and neurological adverse events. Follow-up was short termed. CONCLUSIONS: We found that aripiprazole and risperidone probably reduce symptom severity at short-term follow-up but may also cause adverse events. High-quality and updated SRs and larger randomised controlled trials with longer term follow-up are needed on this topic. OVERVIEW PROTOCOL: PROSPERO CRD42020206535.


Asunto(s)
Trastorno del Espectro Autista , Risperidona , Niño , Humanos , Aripiprazol/uso terapéutico , Trastorno del Espectro Autista/tratamiento farmacológico , Trastorno del Espectro Autista/inducido químicamente , Risperidona/uso terapéutico , Revisiones Sistemáticas como Asunto
6.
Medicine (Baltimore) ; 101(42): e31175, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36281169

RESUMEN

The therapeutic approach of bladder cancer strongly determines its prognosis. We describe the treatments and outcomes for a Spanish cohort of patients with bladder cancer for the first 12 months after diagnosis and identify the factors that influenced the decision to undergo the treatment received. We conducted a multicenter, prospective, cohort study including primary bladder cancer patients during the first 12 months after diagnosis. The clinical outcomes were performance status (ECOG), adverse events and any cause of mortality. We stratified the analysis by factors that might influence the treatments received. We conducted univariate and multivariable logistic regression models to assess which patient and tumor characteristics were associated with receiving adjuvant treatment in the subgroup of noninvasive bladder cancer patients. In total, 314 patients were included (85% men; 53.8% >70 years) in 7 tertiary Spanish hospitals; 82.2% had a noninvasive urothelial bladder cancer (NMIBC). Patients received mostly surgery plus adjuvant therapy (67.7%). BCG (32.8% patients) was the most frequently administered adjuvant therapy, followed by intravesical chemotherapy (17.8% patients) and radiotherapy (10.8%). The variability of administered treatments among hospitals was low. Patients with NMIBC were more likely to receive adjuvant therapy if they had a higher educational level, some comorbidities and a high-grade tumor. The number of fully active patients (ECOG 0) significantly decreased during the first year of follow-up from 58% to 36 % (OR: 2.41, 95%CI 1.82-3.20); at 12-month follow-up 10.8% patients had died from any cause. In conclusion, most of the patients had a NMIBC. Surgery alone or plus adjuvant therapy were the commonest curative options of bladder cancer. BCG therapy was the adjuvant therapy most frequently administered. Higher educational level, presence of comorbidities and a high-grade tumor were associated with adjuvant therapy. Patient performance status was worsening over time. Almost 1 of 10 patients died during the first year of follow-up.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Masculino , Humanos , Femenino , Neoplasias de la Vejiga Urinaria/patología , Estudios Prospectivos , España/epidemiología , Estudios de Cohortes , Cuidados Posteriores , Vacuna BCG/uso terapéutico , Administración Intravesical , Recurrencia Local de Neoplasia/tratamiento farmacológico , Invasividad Neoplásica
7.
Rev. med. Chile ; 150(8): 1046-1053, ago. 2022. tab
Artículo en Español | LILACS | ID: biblio-1431873

RESUMEN

BACKGROUND: Both perfectionism and social anxiety have been described in patients with eating disorders (ED) and medical students. Academic stress also can increase the risk of developing ED. AIM: To analyze the dimensions of perfectionism, social anxiety, and academic stress associated with the risk of developing ED in female medical students. MATERIAL AND METHODS: The Multidimensional Perfectionism Scale, the Liebowitz Social Anxiety Scale, the SISCO academic stress inventory and the Eating Attitudes Test-26, were applied to 163 female medical students from all levels of the career. The groups with and without risk of ED were compared according to these variables. Results: Twenty-four percent of respondents were at risk of ED. There were significant differences between scores of perfectionism, social anxiety, and academic stress between respondents with and without risk for ED. In general, there was a significant correlation among the variables. In a multivariate analysis, the predictors of ED risk were the perception of academic stress (Odds ratio (OR) 1.09; 95% confidence intervals (CI) 1.03-1.16) and personal standards in the context of perfectionism (OR 1.16; 95% CI 1.06-1.27). CONCLUSIONS: A substantial proportion of female medical students were at risk for ED. The risk of ED was determined mainly by academic stress and personal standards in the context of perfectionism. In this sample, social anxiety did not play a relevant role.


Asunto(s)
Humanos , Femenino , Estudiantes de Medicina , Trastornos de Alimentación y de la Ingestión de Alimentos , Perfeccionismo , Ansiedad
9.
BMJ Open ; 12(6): e057555, 2022 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-35725258

RESUMEN

INTRODUCTION: Clinical research broadly aims to influence decision-making in order to promote appropriate healthcare. Funding agencies should prioritise research projects according to needed research topics, methodological and cost-effectiveness considerations, and expected social value. In Chile, there is no local diagnosis regarding recent clinical research that might inform prioritisation for future research funding. This research aims to comprehensively identify and classify Chilean health research studies, elaborating evidence gap maps for the most burdensome local conditions. METHODS AND ANALYSIS: We will search in electronic databases (MEDLINE, Embase, PsycINFO, CINAHL, LILACS and WoS) and perform hand searches to retrieve, identify and classify health research studies conducted in Chile or by authors whose affiliations are based in Chile, from 2000 onwards. We will elaborate evidence matrices for the 20 conditions with the highest burden in Chile (according to the Global Burden of Disease 2019) selected from those defined under the General Regime of the Health Guarantees Act. To elaborate the evidence gap maps, we will consider prioritised interventions and core outcome sets. To identify knowledge gaps and estimate redundant research, we will contrast these gap maps with the available international evidence of high or moderate certainty of evidence, for each specific clinical question. For this purpose, we will search systematic reviews using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. ETHICS AND DISSEMINATION: No ethical approval is required to conduct this project. We will submit our results in both peer-reviewed journals and scientific conferences. We will aim to disseminate our findings through different academic platforms, social media, local press, among others. The final results will be communicated to local funding agencies and government stakeholders. DISCUSSION: We aim to provide an accurate and up-to-date picture of the research gaps-to be filled by new future findings-and the identification of redundant research, which will constitute relevant information for local decision-makers.


Asunto(s)
Proyectos de Investigación , Literatura de Revisión como Asunto , Chile , Análisis Costo-Beneficio , Humanos
10.
Res Synth Methods ; 13(3): 381-388, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35278030

RESUMEN

Overlap of primary studies among systematic reviews (SRs) is one of the main methodological challenges when conducting overviews. If not assessed properly, overlapped primary studies may mislead findings, since they may have a major influence either in qualitative analyses or in statistical weight. Moreover, overlapping SRs may represent the existence of duplicated efforts. Matrices of evidence and the calculation of the overall corrected covered area (CCA) are appropriate methods to address this issue, but they seem to be not comprehensive enough. In this article we present Graphical Representation of Overlap for OVErviews (GROOVE), an easy-to-use tool for overview authors. Starting from a matrix of evidence, GROOVE provides the number of included primary studies and SRs included in the matrix; the absolute number of overlapped and non-overlapped primary studies; and an overall CCA assessment. The tool also provides a detailed CCA assessment for each possible pair of SRs (or "nodes"), with a graphical and easy-to-read representation of these results. Additionally, it includes an advanced optional usage, incorporating structural missingness in the matrix. In this article, we show the details about how to use GROOVE, what results it achieves and how the tool obtains these results. GROOVE is intended to improve the overlap assessment by making it easier, faster, and more friendly for both authors and readers. The tool is freely available at http://doi.org/10.17605/OSF.IO/U2MS4 and https://es.cochrane.org/es/groovetool.


Asunto(s)
Medicina Basada en la Evidencia , Proyectos de Investigación , Revisiones Sistemáticas como Asunto
12.
Environ Sci Pollut Res Int ; 29(32): 48250-48259, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35188613

RESUMEN

Gene expression can be modified in people who are chronically exposed to high concentrations of heavy metals. The soil surrounding the Ventanas Industrial Complex, located on the coastal zone of Puchuncaví and Quintero townships (Chile), contain heavy metal concentrations (As, Cu, Pb, Zn, among others) that far exceed international standards. The aim of this study was to determine the potential association of the heavy metals in soils, especially arsenic, with the status of methylation of four tumor suppressor genes in permanent residents in those townships. To study the methylation status in genes p53, p16, APC, and RASSF1A, we took blood samples from adults living in areas near the industrial complex for at least 5 years and compared it to blood samples from adults living in areas with normal heavy metal concentrations of soils. Results indicated that inhabitants of an area with high levels of heavy metals in soil have a significantly higher proportion of methylation in the promoter region of the p53 tumor suppressor gene compared with control areas (p-value: 0.0035). This is the first study to consider associations between heavy metal exposure in humans and aberrant DNA methylation in Chile. Our results suggest more research to support consistent decision-making on processes of environmental remediation or prevention of exposure.


Asunto(s)
Arsénico , Metales Pesados , Contaminantes del Suelo , Adulto , Arsénico/análisis , Células Sanguíneas/química , Chile , China , Estudios Transversales , Monitoreo del Ambiente/métodos , Genes p53 , Humanos , Metales Pesados/análisis , Metilación , Suelo , Contaminantes del Suelo/análisis , Proteína p53 Supresora de Tumor/genética
13.
Rev Med Chil ; 150(8): 1046-1053, 2022 Aug.
Artículo en Español | MEDLINE | ID: mdl-37358152

RESUMEN

BACKGROUND: Both perfectionism and social anxiety have been described in patients with eating disorders (ED) and medical students. Academic stress also can increase the risk of developing ED. AIM: To analyze the dimensions of perfectionism, social anxiety, and academic stress associated with the risk of developing ED in female medical students. MATERIAL AND METHODS: The Multidimensional Perfectionism Scale, the Liebowitz Social Anxiety Scale, the SISCO academic stress inventory and the Eating Attitudes Test-26, were applied to 163 female medical students from all levels of the career. The groups with and without risk of ED were compared according to these variables. RESULTS: Twenty-four percent of respondents were at risk of ED. There were significant differences between scores of perfectionism, social anxiety, and academic stress between respondents with and without risk for ED. In general, there was a significant correlation among the variables. In a multivariate analysis, the predictors of ED risk were the perception of academic stress (Odds ratio (OR) 1.09; 95% confidence intervals (CI) 1.03-1.16) and personal standards in the context of perfectionism (OR 1.16; 95% CI 1.06-1.27). CONCLUSIONS: A substantial proportion of female medical students were at risk for ED. The risk of ED was determined mainly by academic stress and personal standards in the context of perfectionism. In this sample, social anxiety did not play a relevant role.


Asunto(s)
Trastornos de Alimentación y de la Ingestión de Alimentos , Perfeccionismo , Estudiantes de Medicina , Humanos , Femenino , Ansiedad
15.
BMJ Evid Based Med ; 27(1): 21-26, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-33674258

RESUMEN

BACKGROUND: It is recommended that patients actively participate in clinical practice guideline (CPG) development, which allows consideration of their values and preferences and improves adherence to recommendations. The development of CPGs throughout Latin America is variable and diverse, and the inclusion of patients' participation is unknown. OBJECTIVES: To evaluate the methods of patients' participation in government-sponsored CPGs in Latin America, the type of CPG development and the use of Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methods. DESIGN: Cross-sectional study. We included CPGs developed over the last 10 years through a comprehensive hand search in official national government websites and biomedical databases. MAIN OUTCOME MEASURE: The type of patients' participation was coded according to five predefined categories. We also report the proportion of application of GRADE methods. RESULTS: We included 408 CPGs from 10 countries: 74% (n=303) were de novo development, 13%(n=55) used an adaptation method and 10%(n=41) used both adaptation and de novo methods. Only 45% (n=185) applied the GRADE approach, ranging from 14% (n=12) of CPGs in Brazil to 89% (n=56) of CPGs in Colombia. Only 23% (n=95) of CPGs included at least one method of patients' participation. Mexico was one of the largest CPG producers (100 CPGs), but none included methods of patients' participation; in turn, in countries with lower production of government-sponsored CPGs, patients' participation was found in almost 88%. Guidelines using the GRADE approach were more likely to use methods of patients' participation. These methods were highly variable: 46% (n=44) incorporated patients in the panel, 81% (n=77) searched for evidence about patients' values and preferences, 43% (n=39) used an external review of the draft recommendations by patients, 38% (n=36) used public comments, and 2% included other methods for stakeholders' participation. CONCLUSION: Only one quarter of government-sponsored CPGs in the Latin American region incorporated a method for patients' participation, which varied considerably across the selected countries. These findings highlight the need to improve CPG development methods to systematically incorporate patients' values and preferences when drafting recommendations.


Asunto(s)
Gobierno , Participación del Paciente , Estudios Transversales , Bases de Datos Factuales , Humanos , América Latina
16.
Medicine (Baltimore) ; 100(47): e27801, 2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34964747

RESUMEN

ABSTRACT: The therapeutic approach is crucial to prostate cancer prognosis. We describe treatments and outcomes for a Spanish cohort of patients with prostate cancer during the first 12 months after diagnosis and identify the factors that influenced the treatment they received.This multicenter prospective cohort study included patients with prostate cancer followed up for 12 months after diagnosis. Treatment was stratified by factors such as hospital, age group (<70 and ≥70 years), and D'Amico cancer risk classification. The outcomes were Eastern Cooperative Oncology Group (ECOG) performance status, adverse events (AEs), and mortality. The patient characteristics associated with the different treatment modalities were analyzed using multivariate logistic regression.We included 470 men from 7 Spanish tertiary hospitals (mean (standard deviation) age 67.8 (7.6) years), 373 (79.4%) of which received treatment (alone or in combination) as follows: surgery (n = 163; 34.7%); radiotherapy (RT) (n = 149; 31.7%); and hormone therapy (HT) (n = 142; 30.2%). The remaining patients (n = 97) were allocated to no treatment, that is, watchful waiting (14.0%) or active surveillance (5.7%). HT was the most frequently administered treatment during follow-up and RT plus HT was the most common therapeutic combination. Surgery was more frequent in patients aged <70, with lower histologic tumor grades, Gleason scores <7, and lower prostate-specific antigen levels; while RT was more frequent in patients aged ≥70 with histologic tumor grade 4, and higher ECOG scores. HT was more frequent in patients aged ≥70, with histologic tumor grades 3 to 4, Gleason score ≥8, ECOG ≥1, and higher prostate-specific antigen levels. The number of fully active patients (ECOG score 0) decreased significantly during follow-up, from 75.3% at diagnosis to 65.1% at 12 months (P < .001); 230 (48.9%) patients had at least 1 AE, and 12 (2.6%) patients died.Surgery or RT were the main curative options. A fifth of the patients received no treatment. Palliative HT was more frequently administered to older patients with higher tumor grades and higher Gleason scores. Close to half of the patients experienced an AE related to their treatment.


Asunto(s)
Cuidados Posteriores , Antineoplásicos Hormonales/uso terapéutico , Braquiterapia/efectos adversos , Quimioterapia Adyuvante , Prostatectomía/efectos adversos , Neoplasias de la Próstata/terapia , Anciano , Estudios de Cohortes , Humanos , Masculino , Clasificación del Tumor , Estudios Prospectivos , Antígeno Prostático Específico , Neoplasias de la Próstata/patología , España/epidemiología , Resultado del Tratamiento
17.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34548402

RESUMEN

The timing of reproduction is an adaptive trait in many organisms. In plants, the timing, duration, and intensity of flowering differ between annual and perennial species. To identify interspecies variation in these traits, we studied introgression lines derived from hybridization of annual and perennial species, Arabis montbretiana and Arabis alpina, respectively. Recombination mapping identified two tandem A. montbretiana genes encoding MADS-domain transcription factors that confer extreme late flowering on A. alpina These genes are related to the MADS AFFECTING FLOWERING (MAF) cluster of floral repressors of other Brassicaceae species and were named A. montbretiana (Am) MAF-RELATED (MAR) genes. AmMAR1 but not AmMAR2 prevented floral induction at the shoot apex of A. alpina, strongly enhancing the effect of the MAF cluster, and MAR1 is absent from the genomes of all A. alpina accessions analyzed. Exposure of plants to cold (vernalization) represses AmMAR1 transcription and overcomes its inhibition of flowering. Assembly of the tandem arrays of MAR and MAF genes of six A. alpina accessions and three related species using PacBio long-sequence reads demonstrated that the MARs arose within the Arabis genus by interchromosomal transposition of a MAF1-like gene followed by tandem duplication. Time-resolved comparative RNA-sequencing (RNA-seq) suggested that AmMAR1 may be retained in A. montbretiana to enhance the effect of the AmMAF cluster and extend the duration of vernalization required for flowering. Our results demonstrate that MAF genes transposed independently in different Brassicaceae lineages and suggest that they were retained to modulate adaptive flowering responses that differ even among closely related species.


Asunto(s)
Arabis/metabolismo , Flores/metabolismo , Duplicación de Gen , Regulación de la Expresión Génica de las Plantas , Proteínas de Dominio MADS/metabolismo , Fenotipo , Proteínas de Plantas/metabolismo , Arabis/genética , Arabis/crecimiento & desarrollo , Flores/genética , Flores/crecimiento & desarrollo , Proteínas de Dominio MADS/genética , Proteínas de Plantas/genética
19.
Cochrane Database Syst Rev ; 7: CD013433, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34286511

RESUMEN

BACKGROUND: Stem cell therapy (SCT) has been proposed as an alternative treatment for dilated cardiomyopathy (DCM), nonetheless its effectiveness remains debatable. OBJECTIVES: To assess the effectiveness and safety of SCT in adults with non-ischaemic DCM. SEARCH METHODS: We searched CENTRAL in the Cochrane Library, MEDLINE, and Embase for relevant trials in November 2020. We also searched two clinical trials registers in May 2020. SELECTION CRITERIA: Eligible studies were randomized controlled trials (RCT) comparing stem/progenitor cells with no cells in adults with non-ischaemic DCM. We included co-interventions such as the administration of stem cell mobilizing agents. Studies were classified and analysed into three categories according to the comparison intervention, which consisted of no intervention/placebo, cell mobilization with cytokines, or a different mode of SCT. The first two comparisons (no cells in the control group) served to assess the efficacy of SCT while the third (different mode of SCT) served to complement the review with information about safety and other information of potential utility for a better understanding of the effects of SCT. DATA COLLECTION AND ANALYSIS: Two review authors independently screened all references for eligibility, assessed trial quality, and extracted data. We undertook a quantitative evaluation of data using random-effects meta-analyses. We evaluated heterogeneity using the I² statistic. We could not explore potential effect modifiers through subgroup analyses as they were deemed uninformative due to the scarce number of trials available. We assessed the certainty of the evidence using the GRADE approach. We created summary of findings tables using GRADEpro GDT. We focused our summary of findings on all-cause mortality, safety, health-related quality of life (HRQoL), performance status, and major adverse cardiovascular events. MAIN RESULTS: We included 13 RCTs involving 762 participants (452 cell therapy and 310 controls). Only one study was at low risk of bias in all domains. There were many shortcomings in the publications that did not allow a precise assessment of the risk of bias in many domains. Due to the nature of the intervention, the main source of potential bias was lack of blinding of participants (performance bias). Frequently, the format of the continuous data available was not ideal for use in the meta-analysis and forced us to seek strategies for transforming data in a usable format. We are uncertain whether SCT reduces all-cause mortality in people with DCM compared to no intervention/placebo (mean follow-up 12 months) (risk ratio (RR) 0.84, 95% confidence interval (CI) 0.54 to 1.31; I² = 0%; studies = 7, participants = 361; very low-certainty evidence). We are uncertain whether SCT increases the risk of procedural complications associated with cells injection in people with DCM (data could not be pooled; studies = 7; participants = 361; very low-certainty evidence). We are uncertain whether SCT improves HRQoL (standardized mean difference (SMD) 0.62, 95% CI 0.01 to 1.23; I² = 72%; studies = 5, participants = 272; very low-certainty evidence) and functional capacity (6-minute walk test) (mean difference (MD) 70.12 m, 95% CI -5.28 to 145.51; I² = 87%; studies = 5, participants = 230; very low-certainty evidence). SCT may result in a slight functional class (New York Heart Association) improvement (data could not be pooled; studies = 6, participants = 398; low-certainty evidence). None of the included studies reported major adverse cardiovascular events as defined in our protocol. SCT may not increase the risk of ventricular arrhythmia (data could not be pooled; studies = 8, participants = 504; low-certainty evidence). When comparing SCT to cell mobilization with granulocyte-colony stimulating factor (G-CSF), we are uncertain whether SCT reduces all-cause mortality (RR 0.46, 95% CI 0.16 to 1.31; I² = 39%; studies = 3, participants = 195; very low-certainty evidence). We are uncertain whether SCT increases the risk of procedural complications associated with cells injection (studies = 1, participants = 60; very low-certainty evidence). SCT may not improve HRQoL (MD 4.61 points, 95% CI -5.62 to 14.83; studies = 1, participants = 22; low-certainty evidence). SCT may improve functional capacity (6-minute walk test) (MD 140.14 m, 95% CI 119.51 to 160.77; I² = 0%; studies = 2, participants = 155; low-certainty evidence). None of the included studies reported MACE as defined in our protocol or ventricular arrhythmia. The most commonly reported outcomes across studies were based on physiological measures of cardiac function where there were some beneficial effects suggesting potential benefits of SCT in people with non-ischaemic DCM. However, it is unclear if this intermediate effects translates into clinical benefits for these patients. With regard to specific aspects related to the modality of cell therapy and its delivery, uncertainties remain as subgroup analyses could not be performed as planned, making it necessary to wait for the publication of several studies that are currently in progress before any firm conclusion can be reached. AUTHORS' CONCLUSIONS: We are uncertain whether SCT in people with DCM reduces the risk of all-cause mortality and procedural complications, improves HRQoL, and performance status (exercise capacity). SCT may improve functional class (NYHA), compared to usual care (no cells). Similarly, when compared to G-CSF, we are also uncertain whether SCT in people with DCM reduces the risk of all-cause mortality although some studies within this comparison observed a favourable effect that should be interpreted with caution. SCT may not improve HRQoL but may improve to some extent performance status (exercise capacity). Very low-quality evidence reflects uncertainty regarding procedural complications. These suggested beneficial effects of SCT, although uncertain due to the very low certainty of the evidence, are accompanied by favourable effects on some physiological measures of cardiac function. Presently, the most effective mode of administration of SCT and the population that could benefit the most is unclear. Therefore, it seems reasonable that use of SCT in people with DCM is limited to clinical research settings. Results of ongoing studies are likely to modify these conclusions.


Asunto(s)
Cardiomiopatía Dilatada/terapia , Trasplante de Células Madre , Arritmias Cardíacas/epidemiología , Sesgo , Cardiomiopatía Dilatada/mortalidad , Causas de Muerte , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Humanos , Placebos/uso terapéutico , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Índice de Severidad de la Enfermedad , Trasplante de Células Madre/efectos adversos , Trasplante de Células Madre/mortalidad , Prueba de Paso , Espera Vigilante
20.
Medwave ; 21(3): e8164, 2021 Apr 23.
Artículo en Español, Inglés | MEDLINE | ID: mdl-34081682

RESUMEN

The significant increase in scientific evidence production has led to the creation of methods to facilitate evidence review and synthesis. This has turned, this has resulted in the emergence of different designs depending on the reviews objective. Evidence gap maps constitute a novel approach for literature review. They are thematic collections of a broad field of evidence, using a systematic search strategy that identifies gaps in knowledge and engages, early on, the target audience to design a friendly graphic product. Evidence maps are a tool to be considered in the roster of options available for research funders in that they are particularly useful for evidence-based decision-making and evidence-based policy development. The most commonly used formats to display the findings of evidence gap search designs are the bubble plot and the intervention-outcome framework. This article corresponds to the sixth of a series of narrative reviews on general topics of biostatistics and clinical epidemiology. The purpose of this review is to describe the principal features of evidence gap maps, highlighting their main objectives and utility, exploring the most commonly used mapping formats, and comparing this approach with other evidence synthesis designs.


El gran aumento en la producción de evidencia científica ha llevado a la creación de métodos para facilitar su revisión y síntesis, surgiendo distintos diseños según el objetivo principal que se busque cumplir. Los mapas de brecha de evidencia constituyen un enfoque novedoso de revisión de literatura. Corresponden a colecciones temáticas de un amplio campo de evidencia, utilizando una estrategia de búsqueda sistemática que destaca por identificar brechas o lagunas en el cuerpo de la evidencia disponible y por involucrar tempranamente a la audiencia definida como blanco para el diseño de un producto gráfico amigable. Se han establecido como una herramienta a considerar para guiar la agenda y el financiamiento de futuras investigaciones, y como apoyo en la toma de decisiones y en la creación de políticas basadas en evidencia. Los formatos más utilizados para representar sus hallazgos son el gráfico de burbujas y la grilla intervención-desenlace. Este artículo corresponde al sexto de una serie de revisiones narrativas acerca de tópicos generales en bioestadística y epidemiología clínica, y tiene por objetivo describir las características generales de los mapas de brecha de evidencia, destacar sus principales objetivos y utilidades, explorar los formatos de mapeo más utilizados y comparar este enfoque con otras propuestas de síntesis.


Asunto(s)
Visualización de Datos , Medicina Basada en la Evidencia , Humanos , Revisiones Sistemáticas como Asunto
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