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1.
Hemoglobin ; 36(6): 517-25, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23181747

RESUMEN

We report a new structural defect of the α2-globin chain presenting with moderate microcytic hypochromic anemia, in six individuals from three unrelated families, living in Portugal and Spain. α-Globin gene deletions were ruled out by gap-polymerase chain reaction (gap-PCR) and multiplex ligation-dependent probe amplification (MLPA). Direct sequencing of the α2-globin gene revealed a substitution of codon 104 [α104(G11)Cys→Arg, TGC>CGC (α2) (HBA2:c.313T>C)]. This new variant, not detectable by high performance liquid chromatography (HPLC) or electrophoresis, was called Hb Iberia, as it was observed for the first time in families from the Iberian Peninsula. Although the mutant allele is transcribed, as indicated by the balanced mRNA α/ß ratio, the abnormal α2 chain could not form a stable tetramer as the cysteine and arginine residues, located at the α1ß1 contact, differ in size, charge and hydrophobicity. Hb Iberia is the third mutation described at codon 104 on the α-globin genes, namely, Hb Sallanches (α2, TGC>TAC) and Hb Oegstgeest (α1, TGC>AGC), also characterized as unstable hemoglobins (Hbs), present on an α-thalassemic phenotype.


Asunto(s)
Hemoglobinas Anormales/genética , Globinas alfa/genética , Talasemia alfa/genética , Adulto , Anciano , Sustitución de Aminoácidos , Secuencia de Bases , Codón , Exones , Femenino , Genotipo , Hemoglobinas Anormales/química , Humanos , Masculino , Persona de Mediana Edad , Modelos Moleculares , Mutación Puntual , Portugal , Conformación Proteica , España , Adulto Joven , Globinas alfa/química , Talasemia alfa/diagnóstico
2.
Tumori ; 90(5): 449-57, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15656327

RESUMEN

AIMS AND BACKGROUND: More than 60% of patients with metastatic breast cancer receiving non-platinum-based chemotherapy experience anemia, which is associated with fatigue and impaired quality of life. Epoetin alfa treatment in patients with a variety of malignancies has been shown to decrease transfusion requirements and improve hemoglobin levels and quality-of-life efficacy parameters. PATIENTS: Retrospective subgroup analyses were performed in patients with breast cancer who were part of a multinational, randomized (2:1), double-blind, placebo-controlled trial of anemic cancer patients (n = 375) undergoing non-platinum-based chemotherapy. RESULTS: In the breast cancer subpopulation (n = 114, 48% with stage IV disease at baseline), the hemoglobin increase was greater for epoetin alfa patients than placebo patients (2.3 versus 0.9 g/dL). Epoetin alfa patients had lower transfusion requirements (28.2% versus 33.3%), improvement or preservation versus deterioration of quality of life, and a higher proportion of responders (patients achieving a > or = 2 g/dL increase in hemoglobin levels unrelated to transfusion) (68.0% versus 22.9% for placebo). The results were similar to those observed in the full study cohort, where statistical analyses showed the differences to be significant (P <0.05 for all). Epoetin alfa treatment was well tolerated. Although the study was not designed or powered for survival as an endpoint, Kaplan-Meier estimates for the full cohort showed a trend in overall survival favoring epoetin alfa treatment (P = 0.13, log rank test); a similar benefit was seen in the breast cancer subpopulation. CONCLUSIONS: In the full study cohort and the breast cancer subpopulation, epoetin alfa effectively treated anemia (increased hemoglobin levels and decreased transfusion requirements) and improved or preserved quality of life. Results concerning potential survival benefits support further study of epoetin alfa in anemic cancer patients.


Asunto(s)
Anemia/tratamiento farmacológico , Anemia/etiología , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/complicaciones , Eritropoyetina/uso terapéutico , Hematínicos/uso terapéutico , Anemia/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Transfusión Sanguínea/estadística & datos numéricos , Neoplasias de la Mama/tratamiento farmacológico , Método Doble Ciego , Epoetina alfa , Eritropoyetina/efectos adversos , Europa (Continente) , Femenino , Hematínicos/efectos adversos , Hemoglobinas/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Proteínas Recombinantes , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
3.
Ciênc. agrotec., (Impr.) ; 33(2): 574-579, mar.-abr. 2009. ilus, graf
Artículo en Portugués | LILACS | ID: lil-514009

RESUMEN

A perfilometria é uma técnica amplamente utilizada na construção de mapas e gráficos de relevos aplicados a uma vasta área do conhecimento. Frente às necessidades de suprir a demanda da indústria e da área de desenvolvimento de protótipos quanto a técnicas não invasivas na investigação da superfície de materiais em geral, o presente trabalho buscou propor uma metodologia de calibração aplicada à técnica de moiré para investigações perfilométricas em protótipos mecânicos buscando baixos custos e flexibilidade. A técnica de moiré consiste na comparação de dois retículos periódicos, onde um segue o comportamento da superfície do objeto (retículo modelo - Rm) e outro não está deformado, seguindo o comportamento de um plano de referência, (retículo de referência - Rr). A luz que passa entre os retículos se sobrepõe formando padrões de moiré ou franjas de moiré que se comportam como ondas senoidais. Nos ensaios de calibração, usou-se um cone de relevo conhecido para a determinação de uma constante de correção de mapas gerados digitalmente. Os ensaios realizados aplicaram a metodologia para a determinação do perfil de um mouse de computador e para a determinação da deformação de uma chapa metálica. A metodologia proposta para a calibração da técnica de moiré mostrouse capaz de realizar os mapeamentos, com resolução máxima na ordem de centésimos de milímetros, podendo então ser usada em aplicações com níveis de precisão inferiores a essa ordem.


Profilometry is a measurement technique widely used in map and relief graphic construction, being applied to vast areas of knowledge. The aim of the present investigation was to introduce a calibration method applied to a moiré technique in experiments of mechanical archetypes, with low cost and flexibility, due to the need for supplying demands from both industry and mechanical archetype development for non-invasive techniques. The moiré technique basically consists of the comparison of two periodic structures. One of them follows the behavior of the object surface (reticulum model - Rm) and the other one is kept constant without deformation, working as a reference plane (reference reticulum - Rr). The light that passes between the reticulum overlaps and forms a moiré standard, also called moiré fringe which behaves as sinusoidal waves. In the present calibration tests, a relief cone was used to determine a correction constant in the generated maps. The technique was applied to draw the profile of a computer mouse, and to determine deformation on a metallic blade, mounted over a deformation test table. The proposed methodology for the calibration applied to the moiré technique showed to allow the construction of maps with maximum resolution of hundredths of millimeters. Results also showed that the technique might be used in applications with lower levels of precision as well.

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