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1.
Leuk Res ; 32(6): 976-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18001833

RESUMO

Sequence variation at the proximal MDR1 promoter of 72 patients with acute myeloid leukemia (AML) was investigated and its association with P-glycoprotein (Pgp) expression and activity using flow cytometry were analyzed. Two variants were found: -129T/C and a non-described A/T substitution at position +68 of intron 1 in one patient. Three different genotypes were identified for single nucleotide polymorphism (SNP) -129T/C: 60 patients TT, 11 individuals TC, and 1 CC. No significant association was found between SNP variants and Pgp activity and expression, at protein level. Our data also suggested that an evaluation of MDR1 promoter polymorphisms is of uncertain prognostic value.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Variação Genética , Genoma Humano , Leucemia Mieloide Aguda/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/sangue , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Proc Natl Acad Sci U S A ; 98(10): 5827-32, 2001 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-11320216

RESUMO

Nonlinear-dynamical control techniques, also known as chaos control, have been used with great success to control a wide range of physical systems. Such techniques have been used to control the behavior of in vitro excitable biological tissue, suggesting their potential for clinical utility. However, the feasibility of using such techniques to control physiological processes has not been demonstrated in humans. Here we show that nonlinear-dynamical control can modulate human cardiac electrophysiological dynamics by rapidly stabilizing an unstable target rhythm. Specifically, in 52/54 control attempts in five patients, we successfully terminated pacing-induced period-2 atrioventricular-nodal conduction alternans by stabilizing the underlying unstable steady-state conduction. This proof-of-concept demonstration shows that nonlinear-dynamical control techniques are clinically feasible and provides a foundation for developing such techniques for more complex forms of clinical arrhythmia.


Assuntos
Arritmias Cardíacas/fisiopatologia , Nó Atrioventricular/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Circulation ; 101(11): 1282-7, 2000 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-10725288

RESUMO

BACKGROUND: Clinical studies have shown that biphasic shocks are more effective than monophasic shocks for ventricular defibrillation. The purpose of this study was to compare the efficacy of a rectilinear biphasic waveform with a standard damped sine wave monophasic waveform for the transthoracic cardioversion of atrial fibrillation. METHODS AND RESULTS: In this prospective, randomized, multicenter trial, patients undergoing transthoracic cardioversion of atrial fibrillation were randomized to receive either damped sine wave monophasic or rectilinear biphasic shocks. Patients randomized to the monophasic protocol (n=77) received sequential shocks of 100, 200, 300, and 360 J. Patients randomized to the biphasic protocol (n=88) received sequential shocks of 70, 120, 150, and 170 J. First-shock efficacy with the 70-J biphasic waveform (60 of 88 patients, 68%) was significantly greater than that with the 100-J monophasic waveform (16 of 77 patients, 21%, P<0.0001), and it was achieved with 50% less delivered current (11+/-1 versus 22+/-4 A, P<0.0001). Similarly, the cumulative efficacy with the biphasic waveform (83 of 88 patients, 94%) was significantly greater than that with the monophasic waveform (61 of 77 patients, 79%; P=0.005). The following 3 variables were independently associated with successful cardioversion: use of a biphasic waveform (relative risk, 4.2; 95% confidence intervals, 1.3 to 13.9; P=0.02), transthoracic impedance (relative risk, 0.64 per 10-Omega increase in impedance; 95% confidence intervals, 0.46 to 0.90; P=0.005), and duration of atrial fibrillation (relative risk, 0.97 per 30 days of atrial fibrillation; 95% confidence intervals, 0.96 to 0.99; P=0.02). CONCLUSIONS: For transthoracic cardioversion of atrial fibrillation, rectilinear biphasic shocks have greater efficacy (and require less energy) than damped sine wave monophasic shocks.


Assuntos
Fibrilação Atrial/terapia , Cardioversão Elétrica/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tórax , Resultado do Tratamento
5.
Nat Immun ; 16(5-6): 256-62, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-11061593

RESUMO

Impairment of natural cytotoxicity mediated by natural killer (NK) cells may play a role in the pathogenesis of penile carcinoma. The aim of this study was to examine the NK activity profile and its prognostic significance in patients with squamous cell carcinoma of the penis. The NK activity was measured in peripheral blood mononuclear cells (PBMCs) from 39 patients diagnosed histologically as having invasive squamous cell penile carcinoma and 4 patients with verrucous carcinoma of the penis. Of 39 patients with invasive squamous cell carcinoma, 4 had undergone previous penile amputation. According to the prognosis, the patients with invasive squamous cell carcinoma were divided into two groups: with metastasis and without metastasis. The patients were evaluated in relation to clinicopathologic variables using univariate analyses. NK cell activity was significantly decreased in all patients with penile carcinoma when compared with the control groups (p < 0.0001). There was no statistically significant difference between the groups with and without metastasis. We conclude that there is a decrease in NK activity in PBMCs from patients with penile carcinoma and that the presence of advanced disease or metastatic involvement is not responsible for this reduction.


Assuntos
Carcinoma de Células Escamosas/imunologia , Citotoxicidade Imunológica , Células Matadoras Naturais/imunologia , Neoplasias Penianas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/secundário , Carcinoma Verrucoso/imunologia , Carcinoma Verrucoso/secundário , Estudos de Casos e Controles , Humanos , Técnicas In Vitro , Células K562 , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/imunologia , Estadiamento de Neoplasias , Prognóstico
7.
Aust Dent J ; 42(3): 160-5, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9241925

RESUMO

A review of the literature relating to supernumerary teeth is presented along with four case reports to illustrate some possible presentations, diagnostic features,and treatment options.


Assuntos
Dente Supranumerário/diagnóstico , Adolescente , Criança , Feminino , Humanos , Incisivo/anormalidades , Masculino , Má Oclusão Classe I de Angle/etiologia , Má Oclusão Classe II de Angle/etiologia , Mandíbula , Maxila , Dente Molar/anormalidades , Raiz Dentária/anormalidades , Dente não Erupcionado/diagnóstico
8.
Braz J Med Biol Res ; 28(1): 51-7, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7581028

RESUMO

Some Brazilian regions are considered to be endemic for human T-cell leukemia/lymphoma virus type I (HTLV-I) infection. Several studies have shown a high prevalence of HTLV-I infection among different groups such as blood donors, hemophiliacs and patients suffering from hematological and neurological diseases. Cases of adult T-cell leukemia/lymphoma as well as tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM) have already been described in Brazil. We report the isolation of an HTLV-I strain from cultured lymphocytes of a TSP/HAM patient. An IL-2-dependent HTLV-I-infected T-cell line (ROB) expressing viral antigens was established and reverse transcriptase activity could be detected in the culture supernatant. Ultrastructural analysis showed immature and mature HTLV retrovirus particles. Finally, HTLV-I provirus type I was demonstrated by the polymerase chain reaction. This is the first isolation completely carried out in Latin America. The molecular analysis of viral strains, now in progress, should clarify the molecular epidemiology of HTLV-I in Brazil.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Linfócitos/virologia , Paraparesia Espástica Tropical/epidemiologia , Adulto , Sequência de Bases , Brasil/epidemiologia , Genoma Viral , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/ultraestrutura , Humanos , Masculino , Dados de Sequência Molecular , Paraparesia Espástica Tropical/virologia
9.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;28(1): 51-7, Jan. 1995. ilus, graf
Artigo em Inglês | LILACS | ID: lil-153330

RESUMO

Some Brazilian regions are considered to be endemic for human T-cell leukemia/lymphoma virus type I (HTLV-I) infection. Several studies have shown a high prevalence of HTLV-I infection among different groups such as blood donors, hemophiliacs and patients suffering from hematological and neurological diseases. Cases of adult T -cell leukemia/lymphoma as well as tropical spastic paraparesis/HTLV-i-infected T -cell line (ROB) expressing viral antigens was established and reverse transcriptase activity could be detected in the culture supernatant. Ultrastructural analysis showed immature and mature HTLV retrovirus particles. Finally, HTLV-I provirus type I was demonstrated by the plymerase chain reaction. This is the first isolation completely carried out in Latin America. The molecular analysis of viral strains, now in progress, should clarify the molecular epidemiology of HTLV-I in Brazil


Assuntos
Humanos , Masculino , Adulto , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Linfócitos/virologia , Paraparesia Espástica Tropical/epidemiologia , Brasil/epidemiologia , Genoma Viral , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/ultraestrutura , Estrutura Molecular , Reação em Cadeia da Polimerase
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