Navegando por Palavras-chave "High pressure liquid chromatography"

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    Análise da variação da concentração de amônia, dos aminoácidos alanina e glutamina e do dipeptídeo alanil-glutamina no meio de cultura de embriões humanos e os efeitos na reprodução assistida
    (Universidade Federal de São Paulo (UNIFESP), 2009-03-25) Stevanato, Juliana [UNIFESP]; Bertolla, Ricardo Pimenta [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Objective: to verify the relations between culture media concentrations of ammonia, alanine, glutamine, and alanyl-glutamine and embryo quality, pregnancy, and type of hormonal stimulation. Methods: a prospective case-control study was carried out including 62 embryos from 20 women submitted to assisted reproduction at the Sao Paulo Federal University. Inclusion criteria were age (up to 37 years old), one to four embryos transferred at day 3 of embryo culture, couples submitted to ICSI, and LH peak achieved through hCG administration. Experimental groups were subdivided according to embryo morphologic quality on days 2 and 3, homogenous (good embryos on days 2 and 3) or heterogeneous evolution, type of hormonal stimulation used (FSH or FSH and LH), and occurrence of pregnancy evaluated by serum ƒÒ-hCG. Culture media aliquots were collected after the embryos were transferred. Analysis of alanine, glutamine, alanyl-glutamine, and ammonia concentrations was performed using HPLC. Numerical variables were compared between groups using unpaired Student¡¦s T-test (heteroscedastic variables were transformed), and frequencies using Pearson¡¦s Chi-square or Fisher¡¦s exact test. Logistic models were constructed using female age, type of hormone used for stimulation, embryo quality, and the measured metabolites, in order to maximize predictability of occurrence of pregnancy. Data are presented as mean; standard deviation. Results: In the embryos transferred to women who achieved pregnancy, when compared to those who did not achieve pregnancy, lower levels of normalized glutamine (1.4; 0.7 and 1.9; 0.7, respectively, p=0.004) and ammonia (0.2; 0.01 and 0.3; 0.1, respectively, p=0.008) were observed. Higher levels or normalized alanyl-glutamine were observed in higher quality embryos on days 2 and 3, and on those who presented homogeneous evolution. Embryos from patients who received FSH with LH, when compared to those from patients who received only FSH, presented higher absolute values of alanyl-glutamine (334.9; 95.2 and 282.9; 62.4, respectively, p=0.017). In logistic regression, the model which best predicted pregnancy included all the normalized values of alanine, glutamine, age, type of hormone, and evolution (77.4% correct, p=0.00005). Conclusion: Our results allow us to conclude that, in our conditions: (i) embryos with better quality on days 2 and 3 and with a homogenous evolution are associated with higher contents of alanyl-glutamine in their culture media, (ii) lower levels of ammonia and glutamine in the culture media are associated to higher pregnancy rates, and (iii) FSH with LH during hormonal stimulation is associated to higher levels of alanyl-glutamine in the culture media.
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    Estudo comparativo dos níveis de neurotransmissores no líquor de pacientes com demência com corpúsculos de Lewy, demência da doença de Alzheimer e indivíduos controles
    (Universidade Federal de São Paulo (UNIFESP), 2017-11-30) Miraldo, Marjorie Câmara [UNIFESP]; Mazzacoratti, Maria da Graça Naffah [UNIFESP]; Oliveira, Fabricio Ferreira de [UNIFESP]; http://lattes.cnpq.br/3204275967717703; http://lattes.cnpq.br/0945751507151552; http://lattes.cnpq.br/2144732134557538; Universidade Federal de São Paulo (UNIFESP)
    The early and accurate diagnosis of dementia with Lewy bodies and Alzheimer’s disease dementia needs objective and quantifiable available parameters. These syndromes have many neurodegenerative characteristics in common, which can eventually difficult their differentiation based on the neuropsychological profile. It is known that changes in the metabolism of neurotransmitters are somehow involved in these dementia syndromes. Thus, this study has as main objective the comparative study of neurotransmitter levels in CSF of patients with dementia with Lewy bodies, patients with Alzheimer's disease dementia, and controls without dementia. The levels of the main monoamines were quantified analyzing the content of their metabolites (VMA, MHPG, L-DOPA, DOPAC, 5-HIAA and HVA) as well as neurotransmitter amino acids (Asp, Glu, Gln, Gly, Tau and GABA). The identification of these neurotransmitters as possible cerebrospinal fluid biomarkers, aims at a better diagnostic differentiation among patients with such dementia syndromes. Participants with dementia with Lewy bodies (n = 20) were paired with participants with Alzheimer's disease dementia (n = 20) by gender and cognitive scores (Mini- Mental State Examination and CDR), and paired with controls without dementia (n = 20) by gender and age (± 1 year). Cerebrospinal fluid monoamine metabolites and amino acids were analyzed by high performance liquid chromatography. The concentrations of VMA, 5-HIAA and HVA were lower in both type of patients (dementia with Lewy bodies and in patients with Alzheimer’s disease dementia), when compared with controls without dementia. These data suggest a reduction in the release of norepinephrine, dopamine and serotonin by the brain of patients suffering dementia. Reduced Glu levels in CSF were also found in patients with dementia with Lewy bodies, compared with control subjects, suggesting increased release and metabolization of these neurotransmitters by the brain tissue of these patients. However, despite the alterations found, none of them had difference among the three groups. Thus, this study concluded that none of these neurotransmitters could serve as a specific marker for the dementia syndromes studied.