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1.
Genes Immun ; 17(1): 13-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26492519

RESUMEN

Type 1 diabetes (T1D) is a multifactorial disease that has a strong genetic component. The HLA-G is a nonclassical HLA class I locus that is associated with immunomodulatory functions, including downregulation of innate and adaptive immune responses and induction of immune tolerance. However, there is currently limited information about the involvement of HLA-G in T1D susceptibility. This case-control study aims to investigate the T1D susceptibility association of alleles and genotypes of a widely investigated 14-bp insertion/deletion polymorphism in the HLA-G and to provide further evidence of the frequency distribution of class II HLA-DR-DQ-risk genotypes in T1D children and adolescents in the Brazilian population. The deletion allele and the homozygous deletion genotype are associated with susceptibility to T1D and the insertion allele and the heterozygous deletion/insertion genotype are associated with protection from T1D. We also confirm that genetic susceptibility to T1D is associated with the DRB1*03:01-DQA1*05:01-DQB1*02:01 and DRB1*04-DQA1*03:01-DQB1*03:02 haplotypes in Brazilian northeast region. The DR3-DQ2/DR4-DQ8 genotype conferred the highest detected risk for T1D. Our results identify a novel association of the 14-bp deletion allele and the homozygous deletion genotype with T1D development and provide additional evidence of the importance of HLA class II heterozygous DR3-DQ2/DR4-DQ8 genotype in T1D susceptibility.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Predisposición Genética a la Enfermedad , Antígenos HLA-G/genética , Adolescente , Brasil , Estudios de Casos y Controles , Niño , Femenino , Antígenos HLA-D/genética , Antígenos HLA-D/inmunología , Antígenos HLA-G/inmunología , Haplotipos , Humanos , Masculino , Polimorfismo Genético
2.
Genet Mol Res ; 13(4): 9828-45, 2014 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-25501192

RESUMEN

Morphological characterization is the most accessible and used method to quantify the genetic diversity of the available germplasm. The multivariate statistical method is highly important for this purpose. This study aimed to characterize parents and hybrids of Passiflora according to morphoagronomic descriptors and estimate the genetic divergence between them based on the joint analysis of qualitative and quantitative variables using the Ward-modified location model (MLM) procedure. One hundred and thirty-eight individuals were assessed (10 P. edulis, 10 P. setacea, and 118 interspecific hybrids) using 23 quantitative and 12 qualitative descriptors. The values for the quantitative descriptors were measured and subjected to multivariate statistics using the Ward-MLM strategy. Large genetic variability was detected by the morphoagronomic data in the 138 genotypes that were evaluated, and the hybrids presented higher variability than the parents. Pseudo-F and pseudo-t2 criteria showed that the optimal number of groups was three. Group I was composed of 118 hybrid genotypes; group II was composed of the 10 P. setacea genotypes, and group III was composed of the 10 P. edulis genotypes. The longest distance was found between groups II and III (474.96). The shortest distance was detected between groups I and II (198.78), which indicates that the segregating population is genetically closer to P. setacea than to P. edulis. The Ward-MLM procedure is a useful tool to detect genetic diversity and group accessions using both qualitative and quantitative variables.


Asunto(s)
Hibridación Genética , Passiflora/anatomía & histología , Passiflora/genética , Cruzamientos Genéticos , Flores/anatomía & histología , Flores/genética , Frutas/anatomía & histología , Frutas/genética , Genotipo , Funciones de Verosimilitud , Análisis Multivariante , Fenotipo , Carácter Cuantitativo Heredable , Especificidad de la Especie
3.
Genet Mol Res ; 10(4): 2457-71, 2011 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-22009858

RESUMEN

We estimated genetic parameters through multivariate analysis of two species of Passiflora and their hybrids, considered of ornamental potential, based on the morphological characteristics: flower diameter, corona diameter, corona filament size, flower peduncle length, petal length and width, sepal length and width, internode length, stem diameter, leaf length, leaf width (mm), and leaf area (cm(2)). Five specimens of Passiflora sublanceolata [ex P. palmeri var. sublanceolata], five of P. foetida var. foetida and 20 F(1) hybrids between the two were evaluated. A randomized block design with four replications was used. The data were submitted to variance analysis and multivariate procedures, principal components analysis and unweighted pair group method with arithmetic mean grouping. We found significant differences between genotypes for all these morphological parameters. The hybrid plants had the highest variability, making them the most indicated for future improvement programs. The various multivariate techniques gave similar results, allowing separation of the plants into three distinct groups, these being the two paternal species and the hybrids. The hybrids were closer to the male genitors, revealing a paternal effect on the inheritance of vegetative and floral characters. Based on estimates of genetic parameters, the floral characteristics are the most indicated for the selection of plants for ornamental purposes, since these characteristics displayed greatest variability, a variation index of more than one, and high genotypic determination coefficients.


Asunto(s)
Quimera/genética , Flores/genética , Genotipo , Passiflora/genética , Hojas de la Planta/genética , Tallos de la Planta/genética , Análisis Multivariante , Especificidad de la Especie
4.
Br J Dermatol ; 163(4): 769-75, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20560954

RESUMEN

BACKGROUND: The nonclassical human leucocyte antigen (HLA)-G molecule has been well recognized as a tolerogenic molecule and few studies have evaluated the role of the molecule in inflammatory cutaneous autoimmune diseases. OBJECTIVES: To evaluate the expression of HLA-G in skin specimens of patients with psoriasis and to analyse its correlation with epidemiological and clinical variables. METHODS: Thirty untreated patients with psoriasis and 32 healthy individuals were enrolled. Immunohistochemistry was applied to identify HLA-G expression in formalin-fixed paraffin-embedded cutaneous skin biopsies. RESULTS: Soluble and membrane-bound HLA-G expression was detected in 30 (90%) of the skin specimens from patients presenting clinical and histopathological features of psoriasis. Although infiltrating lymphomononuclear cells of the dermis exhibited HLA-G expression, the epidermis was primarily targeted. HLA-G expression was also observed in 27% (three of 11) of the specimens that exhibited no clinical and histopathological features of psoriasis (nonaffected areas). In contrast, skin specimens obtained from healthy individuals exhibited no HLA-G expression (P < 0·0001). The intensity of HLA-G expression was not associated with type I/II psoriasis, Psoriasis Area and Severity Index score or clinical forms. CONCLUSIONS: As the HLA-G molecule was consistently expressed in affected and, to a lesser extent, in nonaffected areas of untreated patients with psoriasis, irrespective of the severity of the clinical variants, one may hypothesize that the presence of HLA-G may be responsible, at least in part, for the regulation of autoimmune effector cells.


Asunto(s)
Antígenos HLA/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Psoriasis/inmunología , Piel/inmunología , Adolescente , Adulto , Anciano , Epidermis/inmunología , Femenino , Antígenos HLA-G , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Adulto Joven
5.
Environ Sci Pollut Res Int ; 22(23): 18987-93, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26233737

RESUMEN

Energetic characterization of biomass allows for assessing its energy potential for application in different conversion processes into energy. The objective of this study is to physicochemically characterize pineapple crown leaves (PC) for their application in energy conversion processes. PC was characterized according to ASTM E871-82, E1755-01, and E873-82 for determination of moisture, ash, and volatile matter, respectively; the fixed carbon was calculated by difference. Higher heating value was determined by ASTM E711-87 and ash chemical composition was determined by XRF. The thermogravimetric and FTIR analyses were performed to evaluate the thermal decomposition and identify the main functional groups of biomass. PC has potential for application in thermochemical processes, showing high volatile matter (89.5%), bulk density (420.8 kg/m(3)), and higher heating value (18.9 MJ/kg). The results show its energy potential justifying application of this agricultural waste into energy conversion processes, implementing sustainability in the production, and reducing the environmental liabilities caused by its disposal.


Asunto(s)
Ananas/química , Biomasa , Energía Renovable , Agricultura , Carbono/análisis , Hojas de la Planta/química
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