Retos de la investigación en la evaluación de la nutrición y la salud de los inmigrantes: Una revisión narrativa / Research challenges in the assessment of immigrants' nutrition and health: A narrative review

Introducción: Esta revisión narrativa examina los métodos de investigación utilizados para comprender los hábitosalimentarios y el acceso a la salud de los migrantes vulnerables. A menudo se enfrentan a retos que afectan a sus hábitosalimentarios y a su bienestar general. Esta revisión plantea cuestiones metodológicas que los investigadores debenabordar, como la sensibilidad cultural, las barreras lingüísticas, la orientación de los investigadores sobre la selección deherramientas y estrategias adecuadas para garantizar la solidez de su investigación. Objetivos: Esta revisión contribuye a mejorar el rigor metodológico de futuros estudios e informa las intervencionesbasadas en la evidencia, dirigidas a abordar las disparidades en salud y nutrición dentro de las poblaciones inmigrantes vulnerables y destaca la colaboración interdisciplinaria para mejorar las intervenciones dirigidas a promover hábitosalimentarios más saludables entre esta población. Métodos: Se realizó una búsqueda sistemática en bases de datos académicas para identificar bibliografía relevantecentrada en los métodos de investigación y nutrición y salud en inmigrantes. Se incluyeron tanto estudios cualitativoscomo cuantitativos publicados en la última década. Los estudios seleccionados se revisaron críticamente para analizarlas metodologías empleadas, los retos afrontados y los principales hallazgos obtenidos. Conclusiones: Esta revisión destaca la necesidad de adaptaciones metodológicas específicas para cada contexto ysubraya la importancia de la sensibilidad cultural y la colaboración entre investigadores, profesionales y responsablespolíticos para desarrollar intervenciones específicas que promuevan prácticas alimentarias más saludables y mejoren elbienestar de los inmigrantes en circunstancias vulnerables.(AU)

Introduction: This narrative review examines the research methods and analytical approaches used to understand thedietary habits and health access of vulnerable migrants. They often face unique challenges that affect their eating habitsand overall well-being. This review raises methodological issues that researchers must grapple with, including culturalsensitivity, language barriers, the collection of accurate nutrition data, and guidance to researchers on selectingappropriate tools and strategies to ensure the robustness of their research. Objectives: This review contributes to enhancing the methodological rigor of future studies and informs evidence-basedinterventions aimed at addressing healthcare and nutrition disparities within vulnerable immigrant populations, andhighlights the potential for interdisciplinary collaboration to enhance the effectiveness of interventions targeted at promotinghealthier eating habits among vulnerable immigrants from different countries. Methods: A systematic search of academic databases was conducted to identify relevant literature focusing on theresearch methods and nutrition and health in immigrants. Both qualitative and quantitative studies published within the lastdecade were included. The selected studies were critically reviewed to analyze the methodologies employed, thechallenges faced, and the key findings obtained. Conclusion: This review highlights the need for context-specific methodological adaptations, and emphasizes theimportance of cultural sensitivity and collaboration among researchers, practitioners, and policymakers to develop targetedinterventions that promote healthier dietary practices and improve the well-being of immigrants in vulnerable circumstances.(AU)

Genotyping by Sequencing for SNP-Based Linkage Analysis and the Development of KASPar Markers for Male Sterility and Polyembryony in Citrus.

Polyembryony and male sterility (MS) are essential characters for citrus breeding. MS, coupled with parthenocarpy, allows for addressing the diversification of diploid seedless mandarin varieties, and nucleocytoplasmic MS is the most prevalent system. Polyembryony limits the use of seed parents in scion breeding programs, and the recovery of monoembryonic hybrids to be used as female parents is a crucial pre-breeding component. The objectives of this work were the identification of SNPs closely linked with the genes implied in these traits for marker-assisted selection. Genotyping by sequencing was used to genotype 61 diploid hybrids from an F1 progeny recovered from crossing 'Kiyomi' and 'Murcott' tangors. A total of 6444 segregating markers were identified and used to establish the two parental genetic maps. They consisted of 1374 and 697 markers encompassing 1416.287 and 1339.735 cM for 'Kiyomi' and 'Murcott', respectively. Phenotyping for MS and polyembryony was performed. The genotype-trait association study identified a genomic region on LG8 which was significantly associated with MS, and a genomic region on LG1 which was significantly associated with polyembryony. Annotation of the identified region for MS revealed 19 candidate genes. One SNP KASPar marker was developed and fully validated for each trait.

The resistance of sour orange to Citrus tristeza virus is mediated by both the salicylic acid and RNA silencing defence pathways.

Citrus tristeza virus (CTV) induces in the field the decline and death of citrus varieties grafted on sour orange (SO) rootstock, which has forced the use of alternative decline-tolerant rootstocks in affected countries, despite the highly desirable agronomic features of the SO rootstock. Declining citrus plants display phloem necrosis below the bud union. In addition, SO is minimally susceptible to CTV compared with other citrus varieties, suggesting partial resistance of SO to CTV. Here, by silencing different citrus genes with a Citrus leaf blotch virus-based vector, we have examined the implication of the RNA silencing and salicylic acid (SA) defence pathways in the resistance of SO to CTV. Silencing of the genes RDR1, NPR1 and DCL2/DCL4, associated with these defence pathways, enhanced virus spread and accumulation in SO plants in comparison with non-silenced controls, whereas silencing of the genes NPR3/NPR4, associated with the hypersensitive response, produced a slight decrease in CTV accumulation and reduced stunting of SO grafted on CTV-infected rough lemon plants. We also found that the CTV RNA silencing suppressors p20 and p23 also suppress the SA signalling defence, with the suppressor activity being higher in the most virulent isolates.

Citrus leaf blotch virus invades meristematic regions in Nicotiana benthamiana and citrus.

To invade systemically host plants, viruses need to replicate in the infected cells, spread to neighbouring cells through plasmodesmata and move to distal parts of the plant via sieve tubes to start new infection foci. To monitor the infection of Nicotiana benthamiana plants by Citrus leaf blotch virus (CLBV), leaves were agroinoculated with an infectious cDNA clone of the CLBV genomic RNA expressing green fluorescent protein (GFP) under the transcriptional control of a duplicate promoter of the coat protein subgenomic RNA. Fluorescent spots first appeared in agroinfiltrated leaves 11-12 days after infiltration, indicating CLBV replication. Then, after entering the phloem vascular system, CLBV was unloaded in the upper parts of the plant and invaded all tissues, including flower organs and meristems. GFP fluorescence was not visible in citrus plants infected with CLBV-GFP. Therefore, to detect CLBV in meristematic regions, Mexican lime (Citrus aurantifolia) plants were graft inoculated with CLBV, with Citrus tristeza virus (CTV), a virus readily eliminated by shoot-tip grafting in vitro, or with both simultaneously. Although CLBV was detected by hybridization and real-time reverse transcription-polymerase chain reaction (RT-PCR) in 0.2-mm shoot tips in all CLBV-inoculated plants, CTV was not detected. These results explain the difficulty in eliminating CLBV by shoot-tip grafting in vitro.

Development of a full-genome cDNA clone of Citrus leaf blotch virus and infection of citrus plants.

Citrus leaf blotch virus (CLBV), a member of the family Flexiviridae, has a ~9-kb single-stranded, positive-sense genomic RNA encapsidated by a 41-kDa coat protein. CLBV isolates are associated with symptom production in citrus including leaf blotching of Dweet tangor and stem pitting in Etrog citron (Dweet mottle disease), and some isolates are associated with bud union crease on trifoliate rootstocks, but Koch's postulates for this virus were not fulfilled. A full-genome cDNA of CLBV isolate SRA-153, which induces bud union crease, was placed under the T7 promoter (clone T7-CLBV), or between the 35S promoter and the Nos-t terminator, with or without a ribozyme sequence downstream of the CLBV sequence (clones 35SRbz-CLBV and 35S-CLBV). RNA transcripts from T7-CLBV failed to infect Etrog citron and Nicotiana occidentalis and N. benthamiana plants, whereas agro-inoculation with binary vectors carrying 35SRbz-CLBV or 35S-CLBV, and the p19 silencing suppressor, caused systemic infection and production of normal CLBV virions. Virus accumulation was similar in citron plants directly agro-infiltrated, or mechanically inoculated with wild-type or 35SRbz-CLBV-derived virions from Nicotiana, and the three sources incited the symptoms characteristic of Dweet mottle disease, but not bud union crease. Our results show that (1) virions derived from an infectious clone show the same replication, movement and pathogenicity characteristics as the wild-type CLBV; (2) CLBV is the causal agent of Dweet mottle disease but not of the bud union crease syndrome; and (3) for the first time an RNA virus could be successfully agro-inoculated on citrus plants. This infectious clone may become a useful viral vector for citrus genomic studies.