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1.
Glob Health Sci Pract ; 8(4): 813-826, 2020 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-33361244

RESUMEN

BACKGROUND: mHealth interventions are being tested to improve contraceptive uptake in low- and middle-income countries (LMICs); however, the effectiveness of these interventions has not been systematically reviewed. OBJECTIVES: The primary objective of this systematic review was to assess the effectiveness of mHealth interventions to improve contraceptive uptake and adherence in LMICs. A second objective was to identify mHealth features and behavior change communication components used in these mHealth interventions. METHODS: A systematic search was conducted of online databases for peer-reviewed articles that reported on intervention studies with men and women from LMICs and measured mHealth intervention impact on contraceptive uptake and/or adherence. Key search terms included "mHealth" or "mobile health," "contraception" or "family planning," and "low- and middle-income countries." PRISMA guidelines were followed for reporting review methods and findings. The Cochrane risk-of-bias 2 tool for randomized trials was used to assess the risk of bias of the included studies. The GRADE approach was used to determine the quality of evidence. RESULTS: Eight randomized controlled trial studies met the inclusion criteria. Four studies experienced implementation challenges (e.g., intervention components were not utilized fully by participants, intervention participants did not receive the full intervention content, contamination, low response rate, and/or missing data). Only 3 interventions were found to be effective, and these included a "push" approach, interactive communication, information tailored to participants, motivational messaging, and male partner involvement. CONCLUSION: To date, the delivery of mHealth interventions for improving family planning in LMICs has met with implementation challenges that have reduced the researcher's ability to test intervention effectiveness. Although 3 of 8 studies found improved contraceptive use in the intervention group, the review cannot draw concrete conclusions on the overall effectiveness of mHealth interventions to increase contraceptive use in LMICs. Further research with robust program fidelity is recommended.


Asunto(s)
Países en Desarrollo , Telemedicina , Anticoncepción , Anticonceptivos , Femenino , Humanos , Renta , Masculino
2.
BMC Plant Biol ; 18(1): 64, 2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-29661140

RESUMEN

BACKGROUND: Previously, transgenic trichome-bearing (hairy leaf) Brassica napus lines expressing either the Arabidopsis thaliana GL3 gene (line AtGL3+) [1] or the AtGL3 gene in combination with an RNAi construct to down-regulate TTG1 (line K-5-8) [2] were developed. The leaves of these lines exhibited altered insect feeding (flea beetle) and oviposition (diamondback moth) behaviour compared to the non-transgenic semi-glabrous leaves of B. napus cv. Westar. Interestingly, the cotyledons of these lines remained glabrous, but also showed reduced feeding by flea beetles. Here we examine the composition and global transcriptome of the glabrous cotyledons from these transgenic lines to ascertain the mechanism(s) underlying this unexpected phenomenon. RESULTS: Approximately, 7500 genes were up-regulated in cotyledons of each hairy line, compared with < 30 that were down-regulated. The up-regulated genes included those involved in cell wall synthesis, secondary metabolite production, redox, stress and hormone-related responses that have the potential to impact host plant cues required to elicit defense responses toward insect pests. In particular, the expression of glucosinolate biosynthetic and degradation genes were substantially altered in the glabrous cotyledons of the two hairy leaf lines. The transcriptomic data was supported by glucosinolate and cell wall composition profiles of the cotyledons. Changes in gene expression were much more extreme in the AtGL3+ line compared with the K-5-8 line in terms of diversity and intensity. CONCLUSIONS: The study provides a roadmap for the isolation and identification of insect resistance compounds and proteins in the glabrous cotyledons of these hairy leaf lines. It also confirms the impact of mis-expression of GL3 and TTG1 on types of metabolism other than those associated with trichomes. Finally, the large number of up-regulated genes encoding heat shock proteins, PR proteins, protease inhibitors, glucosinolate synthesis/breakdown factors, abiotic stress factors, redox proteins, transcription factors, and proteins required for auxin metabolism also suggest that these cotyledons are now primed for resistance to other forms of biotic and abiotic stress.


Asunto(s)
Brassica napus/metabolismo , Brassica napus/parasitología , Escarabajos/patogenicidad , Cotiledón/metabolismo , Cotiledón/parasitología , Factores de Transcripción/metabolismo , Transcriptoma/genética , Animales , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica napus/genética , Cotiledón/genética , Regulación de la Expresión Génica de las Plantas , Glucosinolatos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Tricomas/genética , Tricomas/metabolismo , Tricomas/parasitología
3.
Transgenic Res ; 26(4): 541-557, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28547343

RESUMEN

MicroRNA156 (miR156) regulates a network of downstream genes to affect plant growth and development. We previously generated alfalfa (Medicago sativa) plants that overexpress homologous miR156 (MsmiR156OE), and identified three of its SPL target genes. These plants exhibited increased vegetative yield, delayed flowering and longer roots. In this study, we aimed to elucidate the effect of miR156 on the root system, including effect on nodulation and nitrogen fixation. We found that MsmiR156 overexpression increases root regeneration capacity in alfalfa, but with little effect on root biomass at the early stages of root development. MsmiR156 also promotes nitrogen fixation activity by upregulating expression of nitrogenase-related genes FixK, NifA and RpoH in roots inoculated with Sinorrhizobium meliloti. Furthermore, we conducted transcriptomics analysis of MsmiR156OE alfalfa roots and identified differentially expressed genes belonging to 132 different functional categories, including plant cell wall organization, peptidyl-hypusine synthesis, and response to water stress. Expression analysis also revealed miR156 effects on genes involved in nodulation, root development and phytohormone biosynthesis. The present findings suggest that miR156 regulates root development and nitrogen fixation activity. Taken together, these findings highlight the important role that miR156 may play as a tool in the biotechnological improvement of alfalfa, and potentially other crops.


Asunto(s)
MicroARNs/genética , Fijación del Nitrógeno/genética , Raíces de Plantas/genética , Plantas Modificadas Genéticamente/genética , Regulación de la Expresión Génica de las Plantas , Medicago sativa/genética , Medicago sativa/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Regeneración/genética
4.
Plant Sci ; 258: 122-136, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28330556

RESUMEN

Alfalfa (Medicago sativa) is an important forage crop that is often grown in areas that frequently experience drought and water shortage. MicroRNA156 (miR156) is an emerging tool for improving various traits in plants. We tested the role of miR156d in drought response of alfalfa, and observed a significant improvement in drought tolerance of miR156 overexpression (miR156OE) alfalfa genotypes compared to the wild type control (WT). In addition to higher survival and reduced water loss, miR156OE genotypes also maintained higher stomatal conductance compared to WT during drought stress. Furthermore, we observed an enhanced accumulation of compatible solute (proline) and increased levels of abscisic acid (ABA) and antioxidants in miR156OE genotypes. Similarly, alfalfa plants with reduced expression of miR156-targeted SPL13 showed reduced water loss and enhanced stomatal conductance, chlorophyll content and photosynthetic assimilation. Several genes known to be involved in drought tolerance were differentially expressed in leaf and root of miR156 overexpression plants. Taken together, our findings reveal that miR156 improves drought tolerance in alfalfa at least partially by silencing SPL13.


Asunto(s)
Silenciador del Gen/fisiología , Medicago sativa/fisiología , MicroARNs/fisiología , Ácido Abscísico/metabolismo , Antioxidantes/metabolismo , Deshidratación/genética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Medicago sativa/genética , Estomas de Plantas/fisiología , Transpiración de Plantas/genética , Transpiración de Plantas/fisiología
5.
Plant Biotechnol J ; 13(6): 779-90, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25532560

RESUMEN

A precursor of miR156 (MsmiR156d) was cloned and overexpressed in alfalfa (Medicago sativa L.) as a means to enhance alfalfa biomass yield. Of the five predicted SPL genes encoded by the alfalfa genome, three (SPL6, SPL12 and SPL13) contain miR156 cleavage sites and their expression was down-regulated in transgenic alfalfa plants overexpressing miR156. These transgenic plants had reduced internode length and stem thickness, enhanced shoot branching, increased trichome density, a delay in flowering time and elevated biomass production. Minor effects on sugar, starch, lignin and cellulose contents were also observed. Moreover, transgenic alfalfa plants had increased root length, while nodulation was maintained. The multitude of traits affected by miR156 may be due to the network of genes regulated by the three target SPLs. Our results show that the miR156/SPL system has strong potential as a tool to substantially improve quality and yield traits in alfalfa.


Asunto(s)
Medicago sativa/genética , MicroARNs/genética , Genoma de Planta , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente
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