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1.
Braz. j. med. biol. res ; 42(9): 783-786, Sept. 2009. graf, tab
Artículo en Inglés | LILACS | ID: lil-524320

RESUMEN

The α-MRE is the major regulatory element responsible for the expression of human α-like globin genes. It is genetically polymorphic, and six different haplotypes, named A to F, have been identified in some population groups from Europe, Africa and Asia and in native Indians from two Brazilian Indian tribes. Most of the mutations that constitute the α-MRE haplotypes are located in flanking sequences of binding sites for nuclear factors. To our knowledge, there are no experimental studies evaluating whether such variability may influence the α-MRE enhancer activity. We analyzed and compared the expression of luciferase of nine constructs containing different α-MRE elements as enhancers. Genomic DNA samples from controls with A (wild-type α-MRE) and B haplotypes were used to generate C-F haplotypes by site-directed mutagenesis. In addition, three other elements containing only the G→A polymorphism at positions +130, +199, and +209, separately, were also tested. The different α-MRE elements were amplified and cloned into a plasmid containing the luciferase reporter gene and the SV40 promoter and used to transiently transfect K562 cells. A noticeable reduction in luciferase expression was observed with all constructs compared with the A haplotype. The greatest reductions occurred with the F haplotype (+96, C→A) and the isolated polymorphism +209, both located near the SP1 protein-binding sites believed not to be active in vivo. These are the first analyses of α-MRE polymorphisms on gene expression and demonstrate that these single nucleotide polymorphisms, although outside the binding sites for nuclear factors, are able to influence in vitro gene expression.


Asunto(s)
Humanos , Regulación de la Expresión Génica/genética , Globinas/genética , Haplotipos/genética , Mutación/genética , Polimorfismo Genético/genética , Elementos Reguladores de la Transcripción/genética , Luciferasas/genética
2.
Braz. j. biol ; 62(4b): 847-852, Nov. 2002. ilus
Artículo en Inglés | LILACS | ID: lil-339384

RESUMEN

The ultrastructural features of the sperm were studied in the hermaphroditic teleost Satanoperca jurupari HECKEL, 1840 from Amazon River. Spermatocytes, spermatids and sperm develop in the testicular cysts among the different oocyte stages. Different stages of early spermatocyte development, mainly the ones with synaptonemal complexes were often observed. The mature spermatozoa belong to the introsperm type, with a short head (aproximadamente 3 mm long and 1.3 mum wide) without acrosome, short midpiece (aproximadamente 1.2 mum long and 1.8 mum wide) containing several mitochondria surrounding two centrioles and forming a mitochondrial collar...


Asunto(s)
Animales , Masculino , Cíclidos , Espermatozoides , Brasil , Microscopía Electrónica de Rastreo
3.
Southeast Asian J Trop Med Public Health ; 1991 Sep; 22(3): 386-92
Artículo en Inglés | IMSEAR | ID: sea-33484

RESUMEN

In an open clinical trial, thirty patients 14 to 44 years old and with acute uncomplicated falciparum malaria were given halofantrine hydrochloride 500 mg (2 tablets) 6-hourly for 3 doses, a total dose of 1500 mg. All 30 patients were cured, with a mean asexual parasite clearance time of 47.6 hours and mean fever clearance time of 36.6 hours. Post-dosing side-effects occurred in 6 patients consisting of mild to moderate headache, dizziness and abdominal muscle spasm. Drug-induced hemolysis did not occur in two G6PD deficient patients. Twenty-three out of 28 isolates tested (82%) were resistant to amodiaquine, 3 (11%) were resistant to the sulfadoxine-pyrimethamine combination, and all were sensitive to chloroquine, quinine and mefloquine by in vitro microtests. The study confirms the efficacy of halofantrine hydrochloride as a blood schizonticide in falciparum malaria.


Asunto(s)
Enfermedad Aguda , Administración Oral , Adolescente , Adulto , Recuento de Células Sanguíneas , Análisis Químico de la Sangre , Resistencia a Medicamentos , Hematócrito , Hemoglobinas/análisis , Humanos , Malaria Falciparum/sangre , Recuento de Huevos de Parásitos , Fenantrenos/administración & dosificación
5.
Rev. cuba. med ; 23(5): 580-7, 1984.
Artículo en Español | LILACS | ID: lil-24888

RESUMEN

Se evaluaron las poblaciones de linfocitos en 13 pacientes con transplante renal (un ano o menos). Se demostro una disminucion en la poblacion de linfocitos T a traves de la roseta espontanea, RE: 47,33% +/- 7, 74 y roseta activa, RA: 32,6% +/- 8,69; en comparacion con los valores normales de RE 73,86% +/- 13,66% y RA: 40,83% +/- 6,90 respectivamente. Se obtuvieron valores incrementados de blastogenesis espontanea (19,45% +/- 11,20), con respecto a los valores normales de 12,5% +/- 5,5, lo que no se correlaciono con la aparicion de rechazo clinico como ha sido reportado por algunos investigadores. Los datos sugieren que la depresion de la inmunocompetencia celular no especifica del paciente transplantado, puede ser un factor importante en el no rechazo del transplante. Por lo que el estudio de la receptividad inmunologica puede ser de gran utilidad en la individualizacion del manejo terapeutico en el pos-transplante


Asunto(s)
Niño , Adolescente , Adulto , Humanos , Masculino , Femenino , Riñón , Linfocitos , Trasplante
6.
Arq. bras. cardiol ; 36(6): 391-5, 1981.
Artículo en Portugués | LILACS | ID: lil-4541

RESUMEN

Os autores realizaram estudo experimental em 15 caes, submetidos a cirurgia cardiaca com circulacao extracorporea e divididos em 3 grupos: grupo I (controle): parada cardiaca anoxica; grupo II (cardioplegia-eletrolitos): parada cardiaca induzida por solucao de eletrolitos a 4oC; grupo III (cardioplegia-eletrolitos, lidocaina, verapamil): parada cardiaca induzida por soluto glicosado, eletrolitos, lidocaina e verapamil. Foram feitas biopsias antes e apos a parada cardiaca de 60 minutos, para microscopia otica e eletronica.Nao se observaram alteracoes a microscopia optica em nenhum dos grupos. O estudo ultra-estrutural mostrou o seguinte: grupo I: edema das mitocondrias e do conjunto perivascular; grupo II: edema das mitocondrias, ruptura das cristas, edema intracelular, ausencia de glicogenio; grupo III: preservacao das mitocondrias, dos granulos de glicogenio e da arquitetura da celula miocardica. Os autores concluiram que a melhor preservacao da estrutura miocardica foi verificada no grupo III


Asunto(s)
Miocardio , Mitocondrias Cardíacas , Paro Cardíaco Inducido
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