Prevalence of vitamin D deficiency in South America: a systematic review and meta-analysis.

CONTEXT: Vitamin D deficiency is considered a global public health issue, even in low-latitude countries where there is abundant sunlight radiation. Nevertheless, the prevalence of vitamin D insufficiency and deficiency in the South American continent has not been well characterized. OBJECTIVE: The aim of this review was to estimate the prevalence of vitamin D deficiency (25-hydroxy-calciferol < 20 ng/mL) in South American populations. DATA SOURCES: Seven electronic databases (MEDLINE, Web of Science, Embase, Biblioteca Virtual de Saúde, SciELO, Scopus, and Google Scholar) were searched systematically for observational studies published before July 1, 2021, and reporting vitamin D status of healthy adults in South America. DATA EXTRACTION: Data were extracted using a standardized form. Risk of bias was assessed by the Joanna Briggs Institute Critical Appraisal Instrument for Studies Reporting Prevalence. All steps were conducted independently by two authors. Data were pooled using a random-effects model. Stratified meta-analysis and meta-regression were conducted (R software). DATA ANALYSIS: Of 9460 articles identified, 96 studies with a total of 227 758 participants were included. The overall prevalence of vitamin D deficiency was 34.76% (79 studies; 95%CI, 29.68-40.21; I2 = 99%). There were significant differences in prevalence rates related to age, sex, country, latitude, season, and year of publication. CONCLUSION: The prevalence of vitamin D deficiency is unexpectedly elevated in South American populations. Public health strategies should include efforts to prevent, detect, and treat vitamin D deficiency. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number CRD42020169439.

Lack of sufficient evidence to support a positive role of selenium status in depression: a systematic review.

CONTEXT: Globally, depression affects more than 322 million people. Studies exploring the relationship between diet and depression have revealed the benefits of certain dietary patterns and micronutrients in attenuating the symptoms of this disorder. Among these micronutrients, selenium stands out because of its multifaceted role in the brain. OBJECTIVE: To assess the impact of selenium intake and status on symptoms of depression. DATA SOURCES: A systematic search was performed in databases, including PubMed, Web of Science, EMBASE, PsycINFO, Scopus, and gray literature (on April 6, 2021, updated on January 28, 2022), without restrictions of date, language, or study type. DATA EXTRACTION: Studies of adults (18-60 y of age) with depression or depressive symptoms were included. Data on selenium biomarkers and/or intake were included. The risk of bias was assessed using the Joanna Briggs Institute checklists. DATA ANALYSIS: Of the 10 studies included, 2 were cohorts (n = 13 983 and 3735), 3 were cross-sectional (n = 736, 7725, and 200), 1 was case-control (n = 495), and 4 were randomized controlled trials (n = 30, 11, 38, and 63). Several studies have indicated that low selenium intake or concentration may be associated with symptoms of depression. However, this association was inconsistent across the studies included in this systematic review; due to the high heterogeneity, it was not possible to perform meta-analyses. The main contributing factors to the high heterogeneity include the different methodological designs, methods for diagnosing depression, selenium assessment, and clinical conditions. CONCLUSION: Overall, there is insufficient evidence to support a positive role of selenium status in depression. Studies with more accurate methods and adequate assessment of selenium status are needed to better understand the role of this nutrient in depression. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42021220683.

Genome-Wide Association Studies Detect Multiple QTLs for Productivity in Mesoamerican Diversity Panel of Common Bean Under Drought Stress.

Drought stress is an important abiotic factor limiting common bean yield, with great impact on the production worldwide. Understanding the genetic basis regulating beans' yield and seed weight (SW) is a fundamental prerequisite for the development of superior cultivars. The main objectives of this work were to conduct genome-wide marker discovery by genotyping a Mesoamerican panel of common bean germplasm, containing cultivated and landrace accessions of broad origin, followed by the identification of genomic regions associated with productivity under two water regimes using different genome-wide association study (GWAS) approaches. A total of 11,870 markers were genotyped for the 339 genotypes, of which 3,213 were SilicoDArT and 8,657 SNPs derived from DArT and CaptureSeq. The estimated linkage disequilibrium extension, corrected for structure and relatedness (r 2 sv ), was 98.63 and 124.18 kb for landraces and breeding lines, respectively. Germplasm was structured into landraces and lines/cultivars. We carried out GWASs for 100-SW and yield in field environments with and without water stress for 3 consecutive years, using single-, segment-, and gene-based models. Higher number of associations at high stringency was identified for the SW trait under irrigation, totaling ∼185 QTLs for both single- and segment-based, whereas gene-based GWASs showed ∼220 genomic regions containing ∼650 genes. For SW under drought, 18 QTLs were identified for single- and segment-based and 35 genes by gene-based GWASs. For yield, under irrigation, 25 associations were identified, whereas under drought the total was 10 using both approaches. In addition to the consistent associations detected across experiments, these GWAS approaches provided important complementary QTL information (∼221 QTLs; 650 genes; r 2 from 0.01% to 32%). Several QTLs were mined within or near candidate genes playing significant role in productivity, providing better understanding of the genetic mechanisms underlying these traits and making available molecular tools to be used in marker-assisted breeding. The findings also allowed the identification of genetic material (germplasm) with better yield performance under drought, promising to a common bean breeding program. Finally, the availability of this highly diverse Mesoamerican panel is of great scientific value for the analysis of any relevant traits in common bean.

Anthropometric, Biochemical, and Food Consumption Parameters are Associated with Venous Leg Ulcer Area and Duration.

OBJECTIVE: To describe the dietary habits and anthropometric and biochemical parameters of patients with active venous leg ulcers and to verify the association of these variables with wound duration and area. DESIGN, SETTING, AND PARTICIPANTS: A cross-sectional study conducted with 33 participants diagnosed with venous leg ulcers in outpatient care. MAIN OUTCOME MEASURES: Socioeconomic data, anthropometric parameters, biochemical parameters, food consumption, and wound characteristics were analyzed by an interprofessional team. MAIN RESULTS: Participants were an average of 58 ± 13 years, 57.6% women, 84.8% overweight, and had a median wound duration of 10 months (range, 1-192 months) and an average wound area of 5 cm (range, 0.22-61.1 cm). Diets were typically hypocaloric and hypoproteic, with a low amount of vitamin A and magnesium. Wound duration was negatively associated with polyunsaturated fat intake (P = .032), whereas wound area was significantly associated with lipid intake (P = .002) and C-reactive protein (P = .040). CONCLUSIONS: Patients with active venous leg ulcers were overweight (leading to systemic inflammation) and had low consumption of calories, protein, and micronutrients that could support cicatrization. Wound area was associated with a high-fat diet, whereas wound duration was negatively associated with polyunsaturated fat intake.

Genomic Prediction of Autotetraploids; Influence of Relationship Matrices, Allele Dosage, and Continuous Genotyping Calls in Phenotype Prediction.

Estimation of allele dosage, using genomic data, in autopolyploids is challenging and current methods often result in the misclassification of genotypes. Some progress has been made when using SNP arrays, but the major challenge is when using next generation sequencing data. Here we compare the use of read depth as continuous parameterization with ploidy parameterizations in the context of genomic selection (GS). Additionally, different sources of information to build relationship matrices were compared. A real breeding population of the autotetraploid species blueberry (Vaccinium corybosum), composed of 1,847 individuals was phenotyped for eight yield and fruit quality traits over two years. Continuous genotypic based models performed as well as the best models. This approach also reduces the computational time and avoids problems associated with misclassification of genotypic classes when assigning dosage in polyploid species. This approach could be very valuable for species with higher ploidy levels or for emerging crops where ploidy is not well understood. To our knowledge, this work constitutes the first study of genomic selection in blueberry. Accuracies are encouraging for application of GS for blueberry breeding. GS could reduce the time for cultivar release by three years, increasing the genetic gain per cycle by 86% on average when compared to phenotypic selection, and 32% when compared with pedigree-based selection. Finally, the genotypic and phenotypic data used in this study are made available for comparative analysis of dosage calling and genomic selection prediction models in the context of autopolyploids.

Differential Metabolism of a Two-Carbon Substrate by Members of the Paracoccidioides Genus.

The genus Paracoccidioides comprises known fungal pathogens of humans and can be isolated from different infection sites. Metabolic peculiarities in different members of the Paracoccidioides led us to perform proteomic studies in the presence of the two-carbon molecule acetate, which predominates in the nutrient-poor environment of the phagosome. To investigate the expression rates of proteins of different members of Paracoccidioides, including one isolate of P. lutzii (Pb01) and three isolates of P. brasiliensis (Pb03, Pb339, and PbEPM83), using sodium acetate as a carbon source, proteins were quantified using label-free and data-independent liquid chromatography-mass spectrometry. Protein profiles of the isolates were statistically analyzed, revealing proteins that were differentially expressed when the fungus was cultivated in a non-preferential carbon source rather than glucose. A total of 1,160, 1,211, 1,280, and 1,462 proteins were reproducibly identified and relatively quantified in P. lutzii and the P. brasiliensis isolates Pb03, Pb339, and PbEPM83, respectively. Notably, 526, 435, 744, and 747 proteins were differentially expressed among P. lutzii and the P. brasiliensis isolates Pb03, Pb339, and PbEPM83, respectively, with a fold-change equal to or higher than 1.5. This analysis revealed that reorganization of metabolism occurred through the induction of proteins related to gluconeogenesis, glyoxylic/glyoxylate cycle, response to stress, and degradation of amino acids in the four isolates. The following differences were observed among the isolates: higher increases in the expression levels of proteins belonging to the TCA and respiratory chain in PbEPM83 and Pb01; increase in ethanol production in Pb01; utilization of cell wall components for gluconeogenesis in Pb03 and PbEPM83; and increased ß-oxidation and methylcitrate cycle proteins in Pb01and PbEPM83. Proteomic profiles indicated that the four isolates reorganized their metabolism in different manners to use acetate as a carbon source.

In-depth genome characterization of a Brazilian common bean core collection using DArTseq high-density SNP genotyping.

BACKGROUND: Common bean is a legume of social and nutritional importance as a food crop, cultivated worldwide especially in developing countries, accounting for an important source of income for small farmers. The availability of the complete sequences of the two common bean genomes has dramatically accelerated and has enabled new experimental strategies to be applied for genetic research. DArTseq has been widely used as a method of SNP genotyping allowing comprehensive genome coverage with genetic applications in common bean breeding programs. RESULTS: Using this technology, 6286 SNPs (1 SNP/86.5 Kbp) were genotyped in genic (43.3%) and non-genic regions (56.7%). Genetic subdivision associated to the common bean gene pools (K = 2) and related to grain types (K = 3 and K = 5) were reported. A total of 83% and 91% of all SNPs were polymorphic within the Andean and Mesoamerican gene pools, respectively, and 26% were able to differentiate the gene pools. Genetic diversity analysis revealed an average H E of 0.442 for the whole collection, 0.102 for Andean and 0.168 for Mesoamerican gene pools (F ST = 0.747 between gene pools), 0.440 for the group of cultivars and lines, and 0.448 for the group of landrace accessions (F ST = 0.002 between cultivar/line and landrace groups). The SNP effects were predicted with predominance of impact on non-coding regions (77.8%). SNPs under selection were identified within gene pools comparing landrace and cultivar/line germplasm groups (Andean: 18; Mesoamerican: 69) and between the gene pools (59 SNPs), predominantly on chromosomes 1 and 9. The LD extension estimate corrected for population structure and relatedness (r2SV) was ~ 88 kbp, while for the Andean gene pool was ~ 395 kbp, and for the Mesoamerican was ~ 130 kbp. CONCLUSIONS: For common bean, DArTseq provides an efficient and cost-effective strategy of generating SNPs for large-scale genome-wide studies. The DArTseq resulted in an operational panel of 560 polymorphic SNPs in linkage equilibrium, providing high genome coverage. This SNP set could be used in genotyping platforms with many applications, such as population genetics, phylogeny relation between common bean varieties and support to molecular breeding approaches.

Isolation and characterization of microsatellite loci in Cabralea canjerana (Meliaceae).

PREMISE OF THE STUDY: Microsatellite primers were developed in the native Neotropical tree species Cabralea canjerana (Vell.) Mart. (Meliaceae) to study population genetics in some Atlantic Forest fragments of Brazil. This species is suitable for use in reforestation and is commercially important due to its high-quality wood. METHODS AND RESULTS: In this study, eight microsatellite loci were isolated from an enriched C. canjerana genomic library. These are the first microsatellite loci described for this genus. Genetic diversity analyses were carried out using 30 individuals and six polymorphic loci. An average of 11.2 alleles was found, and the observed heterozygosity was 0.65. CONCLUSIONS: The microsatellite markers described here are valuable tools for further population genetic studies of the species.

Identification of QTLs associated with citrus resistance to Phytophthora gummosis.

Citrus gummosis, caused by Phytophthora spp., is an important citrus disease in Brazil. Almost all citrus rootstock varieties are susceptible to it to some degree, whereas resistance is present in Poncirus trifoliata, a closely related species. The objective of this study was to detect QTLs linked to citrus Phytophthora gummosis resistance. Eighty individuals of the F1 progeny, obtained by controlled crosses between Sunki mandarin Citrus sunki (susceptible) and Poncirus trifoliata cv. Rubidoux (resistant), were evaluated. Resistance to Phytophthora parasitica was evaluated by inoculating stems of young plants with a disc of fungal mycelia and measuring lesion lengths a month later. Two QTLs linked to gummosis resistance were detected in linkage groups 1 and 5 of the P. trifoliata map, and one QTL in linkage group 2 of the C. sunki map. The phenotypic variation explained by individual QTLs was 14% for C. sunki and ranged from 16 to 24% for P. trifoliata. The low character heritability (h2 = 18.7%) and the detection of more than one QTL associated with citrus Phytophthora gummosis resistance showed that inheritance of the resistance is quantitative.