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2.
Genet Mol Res ; 16(2)2017 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-28407188

RESUMEN

Yacon cultivation has been intensified and the investigations of this crop have increased at the scientific, agricultural, and social levels because the roots of yacon show beneficial properties for human health, such as reducing cholesterol and glucose blood levels. Since the investigations involving yacon are very recent, there is little information available in terms of the genetic characterization of the cultivated genotypes. In view of the lack of information on the accessions cultivated in the State of Espírito Santo, Brazil, this pioneering study aimed to characterize 60 accessions cultivated in the state using ISSR yacon markers with emphasis on identifying the genetic diversity among the materials. The 20 ISSR primers used produced a total of 82 fragments, 39.6% of which presented polymorphism. The number of fragments per primer ranged from 1 to 10. The dissimilarity values ranged from 0 to 0.54 according to the Jaccard coefficient. A dendrogram was generated in which the accessions were divided into 3 groups; group 1 contained 58 individuals and groups 2 and 3 had only one individual in each group. The clustering of 58 accessions in a single group shows the low diversity in the materials examined. This low diversity indicates that new genotypes must be introduced in order to promote increased variability, which would minimize the adverse effects caused by biotic and abiotic factors.


Asunto(s)
Asteraceae/genética , Repeticiones de Microsatélite , Polimorfismo Genético , Asteraceae/clasificación , Genotipo , Filogenia
3.
Genet Mol Res ; 14(4): 16450-60, 2015 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26662443

RESUMEN

Crambe (Crambe abyssinica) is a non-edible annual herb, which was first cultivated to extract oil for industry, and now has great potential for biodiesel production. The objective of this investigation was to evaluate the genetic stability of micropropagated plants of the C. abyssinica Hochst cultivar 'FMS brilhante' using polymerase chain reaction techniques based on inter-simple sequence repeat (ISSR) molecular markers. The aim was to develop a protocol for the in vitro regeneration of these plants with low genetic variation as compared to the donor plant. For micropropagation, shoot tips from in vitro germinated seedlings were used as explants and were initially cultivated for 90 days on MS medium with 5.0 µM 6-benzylaminopurine (BAP), which at 90 days, led to the highest number of shoots per explant (NSE) (12.20 shoots) being detected. After 120 days, the interaction between BAP concentration and naphthalene acetic acid (NAA) was tested, and the highest NSE was observed following exposure to 0.0/0.5 µM BAP/NAA (11.40 shoots) and 1.0/0.0 µM BAP/NAA (11.00 shoots). The highest proportion of rooting phase were observed following exposure to 0.5 µM NAA (30%). The 13 ISSR primers used to analyze genetic stability produced 91 amplification products, of which only eight bands were polymorphic and 83 were monomorphic for all 10 regenerated crambe plants, compared to the donor plant explant. These results indicate that crambe shoot tips are a highly reliable explant that can be used to micropropagate genetically true-to-type plants or to maintain genetic stability, as verified using ISSR markers.


Asunto(s)
Crambe (Planta)/crecimiento & desarrollo , Crambe (Planta)/genética , Inestabilidad Genómica , Repeticiones de Microsatélite , Crambe (Planta)/efectos de los fármacos , ADN de Plantas , Reguladores del Crecimiento de las Plantas/farmacología , Brotes de la Planta
4.
Genet Mol Res ; 14(4): 15892-901, 2015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26634557

RESUMEN

Bromeliads are greatly represented in the Atlantic Forest, although many species are threatened with extinction owing to habitat fragmentation and intense extraction for ornamental purposes. Therefore, it is necessary to conduct studies generating knowledge about genetic diversity and the distribution of this diversity among and within natural populations to establish conservation strategies. These studies can be performed with the use of molecular markers. Molecular markers are advantageous for studies of natural populations, for conservation programs, and to aid in properly classifying plant species. This study aimed to evaluate the genetic diversity among and within natural populations of Pitcairnia flammea, occurring in three fragments of the Atlantic Forest in the southern State of Espírito Santo through the use of inter-simple sequence repeat (ISSR) markers. DNA samples from 55 individuals were amplified with 18 ISSR primers, generating 180 bands, 159 of which were polymorphic. The Shannon genetic diversity index ranged from 0.348 to 0.465, with an average of 0.412. The Bayesian approach for the molecular data indicated the existence of two genetic groups. Analysis of molecular variance indicated the existence of 90.3% diversity within the population and 9.74% among populations. The amount of genetic differentiation of populations was moderate (0.0974), indicating that gene flow rates may be enough to counteract the effects of genetic drift. Greater genetic variability found in population B indicates that this area is an important source of genetic variability.


Asunto(s)
Bromeliaceae/genética , Variación Genética , Genética de Población , Repeticiones de Microsatélite , Bromeliaceae/clasificación , ADN de Plantas , Marcadores Genéticos , Genotipo , Filogenia
5.
Clin Exp Dermatol ; 39(7): 835-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25214407

RESUMEN

In cutaneous lupus erythematosus (CLE), the pathogenetic role of cytotoxic granules has been demonstrated in the subacute and discoid subtypes, which show interface dermatitis, but little is known about tumid (T)CLE, which does not show this interface dermatitis, and evolves with minimal epidermal changes. We studied cytotoxic T lymphocytes and cytotoxic granules in discoid (n = 21), subacute (n = 17), and tumid (n = 21) CLE samples. Skin sections were immunohistochemically stained for CD8, CD56, perforin, granzyme A, granzyme B, and granulysin. Inflammatory cells containing the four subtypes of cytotoxic granules were found in all the three CLE forms; however, only the TCLE group showed a positive correlation between the density of CD8+ cells and each subtype of cytotoxic granule-positive cells. In addition, only the TCLE group showed synergy between the densities of cells containing cytotoxic granule subtypes. Cytotoxic granules are important in the pathomechanism of TCLE. They may perform functions other than apoptosis, including maintenance of inflammation and dermal mucinous deposits in TCLE.


Asunto(s)
Lupus Eritematoso Cutáneo/inmunología , Linfocitos T Citotóxicos/inmunología , Antígenos de Diferenciación de Linfocitos T/metabolismo , Antígeno CD56/análisis , Linfocitos T CD8-positivos/inmunología , Recuento de Células , Granzimas/metabolismo , Humanos , Inmunohistoquímica , Lupus Eritematoso Cutáneo/metabolismo , Lupus Eritematoso Cutáneo/patología , Perforina/metabolismo , Estudios Retrospectivos
6.
Clin Exp Dermatol ; 39(8): 868-73, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25156792

RESUMEN

BACKGROUND: Chronic telogen effluvium (CTE), a poorly understood condition, can be confused with or may be a prodrome to female pattern hair loss (FPHL). The pathogenesis of both is related to follicle cycle shortening and possibly to blood supply changes. AIM: To analyze a number of histomorphometric and immunohistochemical findings through vascular endothelial growth factor (VEGF), Ki-67, and CD31 immunostaining in scalp biopsies of 20 patients with CTE, 17 patients with mild FPHL and 9 controls. METHODS: Ki-67 index and VEGF optical density were analyzed at the follicular outer sheath using ImageJ software. CD31 microvessel density was assessed by a Chalkley grid. RESULTS: Significant follicle miniaturization and higher density of nonanagen follicles were found in FPHL, compared with patients with CTE and controls. Ki-67+ index correlated positively with FPHL histological features. The FPHL group showed the highest VEGF optical density, followed by the CTE and control groups. No differences were found in CD31 microvessel density between the three groups. CONCLUSIONS: Histomorphometric results establish CTE as a distinct disorder, separate from FPHL from its outset. Its pathogenic mechanisms are also distinct. These findings support the proposed mechanism of 'immediate telogen release' for CTE, leading to cycle synchronization. For FPHL, accelerated anagen follicular mitotic rates and, thus, higher Ki-67 and VEGF values, would leave less time for differentiation, resulting in hair miniaturization.


Asunto(s)
Alopecia , Folículo Piloso , Adolescente , Adulto , Anciano , Alopecia/etiología , Alopecia/metabolismo , Alopecia/patología , Estudios de Casos y Controles , Enfermedad Crónica , Femenino , Folículo Piloso/irrigación sanguínea , Folículo Piloso/patología , Humanos , Inmunohistoquímica , Antígeno Ki-67/metabolismo , Persona de Mediana Edad , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Estudios Prospectivos , Cuero Cabelludo/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adulto Joven
7.
Genet Mol Res ; 13(3): 4766-75, 2014 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-25062412

RESUMEN

We characterized single primer amplification reaction (SPAR) molecular markers from 20 genotypes of Anthurium andraeanum Lind., including 3 from commercial varieties and 17 from 2 communities in the State of Espírito Santo, Brazil. Twenty-four SPAR, consisting of 7 random amplified polymorphic DNA and 17 inter-simple sequence repeat markers were used to estimate the genetic diversity of 20 Anthurium accessions. The set of SPAR markers generated 288 bands and showed an average polymorphism percentage of 93.39%, ranging from 71.43 to 100%. The polymorphism information content (PIC) of the random amplified polymorphic DNA primers averaged 0.364 and ranged from 0.258 to 0.490. Primer OPF 06 showed the lowest PIC, while OPAM 14 was the highest. The average PIC of the inter-simple sequence repeat primers was 0.299, with values ranging from 0.196 to 0.401. Primer UBC 845 had the lowest PIC (0.196), while primer UCB 810 had the highest (0.401). By using the complement of Jaccard's similarity index and unweighted pair group method with arithmetic mean clustering, 5 clusters were formed with a cophenetic correlation coefficient of 0.8093, indicating an acceptable clustering consistency. However, no genotype clustering patterns agreed with the morphological data. The Anthurium genotypes investigated in this study are a germplasm source for conservational research and may be used in improvement programs for this species.


Asunto(s)
Araceae/genética , Flores/genética , Genotipo , Filogenia , Polimorfismo Genético , Araceae/anatomía & histología , Araceae/clasificación , Brasil , Cruzamiento , Dermatoglifia del ADN , Cartilla de ADN , Flores/anatomía & histología , Flores/clasificación , Marcadores Genéticos , Repeticiones de Microsatélite , Familia de Multigenes , Técnica del ADN Polimorfo Amplificado Aleatorio
8.
Bone Marrow Transplant ; 48(12): 1525-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23892328

RESUMEN

The objective of this study was to test the relationship between histological changes in minor salivary glands (MSG) and chronic GVHD (cGVHD) severity and OS of hematopoietic SCT (HSCT) patients, and to discriminate the participation of events preceding HSCT that damage MSG, from those linked to cGVHD. The MSG of 57 HSCT patients who were divided into two groups-oral cGVHD (36 cases) and non-cGVHD (21 cases)-were compared with the MSG of a control group of 19 non-HSCT individuals. cGVHD changes were assessed according to National Institutes of Health (NIH) consensus and the systems of Horn et al. Acinar areas and mononuclear cell subsets were set through morphometry. Horn's 'periductal lymphocytic infiltrate' correlated with an extensive form of cGVHD and NIH 'periductal lymphocytes with exocytosis into duct' correlated with global survival. Measurements of the acinar area differed between the three groups, being the lowest in cGVHD patients, but also reduced in non-cGVHD patients. Significant differences among CD45, CD45RO, CD4 and CD8 immunomarked cells/mm(2) were found by comparing the two groups of HSCT patients. In brief, periductal lymphocytic infiltrate and exocytosis implies inflammatory activity and, consequently, might reflect the cGVHD status and influence survival. Acini loss in non-cGVHD patients may be due to pre-transplant events, but massive lymphocyte infiltrate is part of the cGVHD process.


Asunto(s)
Enfermedad Injerto contra Huésped/patología , Trasplante de Células Madre Hematopoyéticas/métodos , Glándulas Salivales Menores/patología , Trasplante Autólogo/efectos adversos , Adolescente , Adulto , Niño , Femenino , Enfermedad Injerto contra Huésped/inmunología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Glándulas Salivales Menores/inmunología , Acondicionamiento Pretrasplante/efectos adversos , Acondicionamiento Pretrasplante/métodos , Adulto Joven
9.
Genet Mol Res ; 10(1): 140-9, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21308655

RESUMEN

Dry beans are considered to be a crop of great socio-economic importance, because they are an inexpensive source of nutrients and because their cultivation requires considerable manual labor. Studies of genetic diversity have been very important for genetic improvement programs, because they give parameters for the identification of genitors that can provide large heterosis effects and improved segregation in recombinants, increasing the probability of obtaining superior genotypes in the progeny. We evaluated the genetic diversity of 57 dry bean accessions, including 31 local accessions, propagated by small-scale farmers, 20 accessions supplied by the Brazilian Agricultural Research Agency, and six commercial accessions, using 16 microsatellite primers. Among these primers, 13 were found to be polymorphic, giving 29 polymorphic alleles. The largest number of alleles per locus was observed for primer BM141, which had four alleles. The polymorphic information content varied from 0.11 to 0.51, observed for loci BM212 and BM141, respectively. The lowest degree of dissimilarity (0.0) was found between the accession Iapar 81 and the accessions E03, E04, E09, and E13 and between the accession pairs E08 with E16 and Iapar 31 with E06. The highest degree of dissimilarity was found between the accessions Carioca and E22 (1.0). Grouping analysis revealed four groups, according to the place of origin. This tendency was also found in the principal coordinate analysis. The local genotypes were found to have relatively high genetic diversity, while the EMBRAPA and commercial cultivars had a relatively narrow genetic basis.


Asunto(s)
Variación Genética/genética , Repeticiones de Microsatélite/genética , Phaseolus/genética , Phaseolus/clasificación
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