106 research outputs found
CaracterizaciĂłn ClĂnica e HistopatolĂłgica del Carcinoma Baso celular
Introduction: The basaloma also known as basal cell carcinoma is the most frequent case of skin cancer. It can be seen mostly in face, nose and forehead.Objective: To identify the clinical and histopathological characteristics of basal cell carcinoma in patients who underwent surgery at the Maxillo Facial Service of the Celia SĂĄnchez Manduley University Hospital in Manzanillo, during the period from September to December 2016.Methodological Design: It was carried out a descriptive and observant study to identify the clinical and histopathological characteristics of the basal cell carcinoma in patients that were treated in the Maxillofacial Service of the Clinical-Surgical Hospital ÂŽÂŽ Celia SĂĄnchez ManduleyÂŽÂŽ, between the months of September and December of 2016. The sample had 60 patients.Results: The basal cell carcinoma predominated in males (55%) mostly between the ages of 60 and 80 years (68,67%). This disease was most frequently presented in white people (75%); located mainly in the cheeks (43%), with a size between one and two centimeters. These lesions presented a low diagnosis error with only a two percentage.Conclusions: The research reveal a high frequency of this disease in elderly people mostly men, with a bigger tendency to be located in the facial regions sun exposed. It was also confirmed that these lesions were detected and treated in early stages. Their diagnosis and treatment are performed with a small margin of error.IntroducciĂłn: el basaloma, tambiĂ©n llamado carcinoma de cĂ©lulas basales y carcinoma basocelular, es la forma mĂĄs frecuente de cĂĄncer de piel y se puede encontrar principalmente en cara, nariz y frente.Objetivo: identificar las caracterĂsticas clĂnicas e histopatolĂłgicas del carcinoma basocelular en pacientes que fueron operados en el Servicio de MĂĄxilo Facial del Hospital Universitario Celia SĂĄnchez Manduley de Manzanillo, en el perĂodo comprendido entre los meses de septiembre a diciembre de 2016.Material y MĂ©todos: se realizĂł un estudio observacional, descriptivo y de corte transversal para identificar las caracterĂsticas clĂnicas e histopatolĂłgicas del carcinoma basocelular en pacientes que fueron operados en el Servicio de MĂĄxilo Facial del Hospital ClĂnico-quirĂșrgico Celia SĂĄnchez Manduley de Manzanillo, en el perĂodo comprendido entre los meses de septiembre a diciembre de 2016. La muestra estuvo constituida por 60 pacientes.Resultados: el carcinoma basocelular predominĂł en el sexo masculino (55%) sobre todo en las edades de 60 a 80 años (68,67%). Esta lesiĂłn se presentĂł con mayor frecuencia en personas de piel blanca (75%); localizĂĄndose principalmente en las mejillas (43%) con un tamaño predominante de 1 a 2 cm. Esta lesiĂłn presentĂł bajo error diagnĂłstico con solo el 2%. Conclusiones: la investigaciĂłn revelĂł una alta frecuencia de la enfermedad en personas de edad avanzada sobre todo en hombres, con mayor tendencia a presentarse en regiones faciales expuestas al sol. TambiĂ©n se constatĂł que las lesiones son detectadas y tratadas en un estado incipiente. Su diagnĂłstico y tratamiento se realzan con un margen de error muy pequeño
The Origin and Genetic Variation of Domestic Chickens with Special Reference to Junglefowls Gallus g. gallus and G. varius
It is postulated that chickens (Gallus gallus domesticus) became domesticated from wild junglefowls in Southeast Asia nearly 10,000 years ago. Based on 19 individual samples covering various chicken breeds, red junglefowl (G. g. gallus), and green junglefowl (G. varius), we address the origin of domestic chickens, the relative roles of ancestral polymorphisms and introgression, and the effects of artificial selection on the domestic chicken genome. DNA sequences from 30 introns at 25 nuclear loci are determined for both diploid chromosomes from a majority of samples. The phylogenetic analysis shows that the DNA sequences of chickens, red and green junglefowls formed reciprocally monophyletic clusters. The Markov chain Monte Carlo simulation further reveals that domestic chickens diverged from red junglefowl 58,000±16,000 years ago, well before the archeological dating of domestication, and that their common ancestor in turn diverged from green junglefowl 3.6 million years ago. Several shared haplotypes nonetheless found between green junglefowl and chickens are attributed to recent unidirectional introgression of chickens into green junglefowl. Shared haplotypes are more frequently found between red junglefowl and chickens, which are attributed to both introgression and ancestral polymorphisms. Within each chicken breed, there is an excess of homozygosity, but there is no significant reduction in the nucleotide diversity. Phenotypic modifications of chicken breeds as a result of artificial selection appear to stem from ancestral polymorphisms at a limited number of genetic loci
Genetic diversity analysis in the section Caulorrhizae (genus Arachis) using microsatellite markers
Diversity in 26 microsatellite loci from section Caulorrhizae germplasm was evaluated by using 33 accessions of A. pintoi Krapov. & W.C. Gregory and ten accessions of Arachis repens Handro. Twenty loci proved to be polymorphic and a total of 196 alleles were detected with an average of 9.8 alleles per locus. The variability found in those loci was greater than the variability found using morphological characters, seed storage proteins and RAPD markers previously used in this germplasm. The high potential of these markers to detect species-specific alleles and discriminate among accessions was demonstrated. The set of microsatellite primer pairs developed by our group for A. pintoi are useful molecular tools for evaluating Section Caulorrhizae germplasm, as well as that of species belonging to other Arachis sections
Representativeness of microsatellite distributions in genomes, as revealed by 454 GS-FLX Titanium pyrosequencing
<p>Abstract</p> <p>Background</p> <p>Microsatellites are markers of choice in population genetics and genomics, as they provide useful insight into patterns and processes as diverse as genome evolutionary dynamics and demographic processes. The acquisition of microsatellites through multiplex-enriched libraries and 454 GS-FLX Titanium pyrosequencing is a promising new tool for the isolation of new markers in unknown genomes. This approach can also be used to evaluate the extent to which microsatellite-enriched libraries are representative of the genome from which they were isolated. In this study, we deciphered potential discrepancies in microsatellite content recovery for two reference genomes (<it>Apis mellifera </it>and <it>Danio rerio</it>), selected on the basis of their extreme heterogeneity in terms of the proportions and distributions of microsatellites on chromosomes.</p> <p>Results</p> <p>The <it>A. mellifera </it>genome, in particular, was found to be highly heterogeneous, due to extremely high rates of recombination, with hotspots, but the only bias consistently introduced into pyrosequenced multiplex-enriched libraries concerned sequence length, with the overrepresentation of sequences 160 to 320 bp in length. Other deviations from expected proportions or distributions of motifs on chromosomes were observed, but the significance and intensity of these deviations was mostly limited. Furthermore, no consistent adverse competition between multiplexed probes was observed during the motif enrichment phase.</p> <p>Conclusions</p> <p>This approach therefore appears to be a promising strategy for improving the development of microsatellites, as it introduces no major bias in terms of the proportions and distribution of microsatellites.</p
Missense and nonsense mutations in melanocortin 1 receptor (MC1R) gene of different goat breeds: association with red and black coat colour phenotypes but with unexpected evidences
<p>Abstract</p> <p>Background</p> <p><it>Agouti </it>and <it>Extension </it>loci control the relative amount of eumelanin and pheomelanin production in melanocytes that, in turn, affects pigmentation of skin and hair. The <it>Extension </it>locus encodes the melanocortin 1 receptor (MC1R) whose permanent activation, caused by functional mutations, results in black coat colour, whereas other inactivating mutations cause red coat colour in different mammals.</p> <p>Results</p> <p>The whole coding region of the <it>MC1R </it>gene was sequenced in goats of six different breeds showing different coat colours (Girgentana, white cream with usually small red spots in the face; Maltese, white with black cheeks and ears; Derivata di Siria, solid red; Murciano-Granadina, solid black or solid brown; Camosciata delle Alpi, brown with black stripes; Saanen, white; F<sub>1 </sub>goats and the parental animals). Five single nucleotide polymorphisms (SNPs) were identified: one nonsense mutation (p.Q225X), three missense mutations (p.A81V, p.F250V, and p.C267W), and one silent mutation. The stop codon at position 225 should cause the production of a shorter MC1R protein whose functionality may be altered. These SNPs were investigated in a larger sample of animals belonging to the six breeds. The Girgentana breed was almost fixed for the p.225X allele. However, there was not complete association between the presence of red spots in the face and the presence of this allele in homozygous condition. The same allele was identified in the Derivata di Siria breed. However, its frequency was only 33%, despite the fact that these animals are completely red. The p.267W allele was present in all Murciano-Granadina black goats, whereas it was never identified in the brown ones. Moreover, the same substitution was present in almost all Maltese goats providing evidence of association between this mutation and black coat colour.</p> <p>Conclusion</p> <p>According to the results obtained in the investigated goat breeds, <it>MC1R </it>mutations may determine eumelanic and pheomelanic phenotypes. However, they are probably not the only factors. In particular, the surprising not complete association of the nonsense mutation (p.Q225X) with red coat colour raises a few hypotheses on the determination of pheomelanic phenotypes in goats that should be further investigated.</p
Pollen Competition as a Reproductive Isolation Barrier Represses Transgene Flow between Compatible and Co-Flowering Citrus Genotypes
Background/Objective: Despite potential benefits granted by genetically modified (GM) fruit trees, their release and commercialization raises concerns about their potential environmental impact, and the transfer via pollen of transgenes to cross-compatible cultivars is deemed to be the greatest source for environmental exposure. Information compiled from field trials on GM trees is essential to propose measures to minimize the transgene dispersal. We have conducted a field trial of seven consecutive years to investigate the maximum frequency of pollen-mediated crop-to-crop transgene flow in a citrus orchard, and its relation to the genetic, phenological and environmental factors involved. Methodology/Principal Findings: Three different citrus genotypes carrying the uidA (GUS) tracer marker gene (pollen donors) and a non-GM self-incompatible contiguous citrus genotype (recipient) were used in conditions allowing natural entomophilous pollination to occur. The examination of 603 to 2990 seeds per year showed unexpectedly low frequencies (0.17-2.86%) of transgene flow. Paternity analyses of the progeny of subsets of recipient plants using 10 microsatellite (SSR) loci demonstrated a higher mating competence of trees from another non-GM pollen source population that greatly limited the mating chance of the contiguous cross-compatible and flowering-synchronized transgenic pollen source. This mating superiority could be explained by a much higher pollen competition capacity of the non-GM genotypes, as was confirmed through mixed-hand pollinations. Conclusions/Significance: Pollen competition strongly contributed to transgene confinement. Based on this finding, suitable isolation measures are proposed for the first time to prevent transgene outflow between contiguous plantings of citrus types that may be extendible to other entomophilous transgenic fruit tree species. (Résumé d'auteur
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