RESUMO
BACKGROUND: Apolipoprotein E (ApoE) ε4 genotype is the most clearly documented risk factor for Alzheimer's disease (AD). Epidemiological studies demonstrate an accelerated rate of progression to dementia and AD in patients with mild cognitive impairment (MCI). We assessed the ApoE allele and genotypes frequencies in Cuban patients with MCI. METHODS: We performed ApoE genotyping of 74 Cuban patients more than 65 years old. Cognitive assessments included the Mini-Mental State Examination (MMSE) and a cognitive battery for evaluating memory, attention, perception, and executive function. RESULTS: Cognitive impairments were characterized by amnesia and executive deficits in patients with MCI. The Apo ε4 allele frequency was 0.196 in patients with MCI, 10-fold higher than that in the controls. Patients carrying the ε4 allele exhibited poorer performance in MMSE and tests assessing executive function and short-term memory than noncarriers. CONCLUSIONS: The patients exhibited amnestic MCI multiple domains. Cognitive performance was worse in patients who carried the ApoE ε4 allele.
Assuntos
Apolipoproteínas E/genética , Disfunção Cognitiva/genética , Frequência do Gene/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Apolipoproteína E4/genética , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Cuba/epidemiologia , Feminino , Humanos , MasculinoRESUMO
DNA molecules suitable for amplification by Polymerase Chain Reaction were obtained by immobilizing whole blood or isolated leukocytes and incubating the immobilized cells for one hour with the known non-enzymatic solution described for preparing intact DNA molecules for PFGE. Cell immobilization was done in agarose gels and punches of 1.2 mm of diameter had the amount of DNA needed for amplifying chromosomal and mitochondrial sequences, many times. The approach was successfully used in preparing DNA molecules from multiple samples in flat-bottom 96-well ELISA plates. The procedure is simple and does not demand special conditions for sample transportation or conservation; thus, it should be useful to collect and process samples under field conditions in epidemiological studies.
Assuntos
Técnicas Biossensoriais , Células Sanguíneas/metabolismo , DNA/sangue , DNA/isolamento & purificação , Sequência de Bases , Células Sanguíneas/química , Cromossomos Humanos/genética , DNA/genética , DNA Mitocondrial/genética , Eletroforese em Gel de Ágar , Humanos , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase , Sensibilidade e EspecificidadeRESUMO
In the present work, a label immunoquantification procedure was developed in order to determine the number of markers introduced into DNA. A non-enzymatic, in vitro labeling method for introducing the p-bromobenzoyl radical (label), through transamination and acylation reactions of the cytidine nucleotides in calf thymus DNA, was carried out. Three spacer arms with different lengths were used for separating the label from the nucleotide and three labeled DNA were obtained. Anti-p-bromobenzoyl chicken IgY polyclonal antibodies were obtained. The antibodies detected the label, into three-labeled DNA, with different sensitivities, in relation to spacer arm length used. About 3-11 labels per 4 x 10(6) bases into thermally denatured DNA were immunoquantified.
Assuntos
DNA/análise , DNA/química , Ensaio de Imunoadsorção Enzimática/métodos , Immunoblotting/métodos , Imunoglobulinas/análise , Imunoglobulinas/química , Coloração e Rotulagem/métodos , Animais , Galinhas , Enzimas/química , Sondas Moleculares/análise , Sondas Moleculares/químicaRESUMO
Monomeric and chimeric synthetic peptides were used as coating antigens in four different mixtures in a solid phase immunoassay to select an optimal combination for the detection of antibodies to human T-cell lymphotropic virus (HTLV) in serum samples. The peptides, P-13 (gp21 I), Q5 (gp21 II)-GG-(gp46 II), and Q (gp46 I)-GG-(p19 I), represent immunodominant sequences from transmembrane protein (gp21), envelope protein (gp46), and core protein (p19) of HTLV I/II viruses; they were the most antigenic and specific peptides in previous studies. The sequences of the chimeric peptides were separated by two glycine residues. An indirect UltramicroEnzyme-linked immunosorbent assay (UMELISA) was used to evaluate the antigenicity of these peptide mixtures by using samples from anti-HTLV I/II PRP205(M), (n = 20), HTLV I-infected individuals from Cuba (n = 7), and HTLV I-positive sera from Colombia and Chile (n = 9). The specificity was evaluated with healthy blood donor sera (n = 300), anti-HIV 1-positive samples (n = 10), and other seropositive samples to different infectious agents. The highest sensitivity and specificity was obtained with mixture 1, which could be very useful in the immunodiagnostic of HTLV infection.
