LEDA LEME TALIB
Projetos de Pesquisa
Unidades Organizacionais
Instituto de Psiquiatria, Hospital das Clínicas, Faculdade de Medicina
LIM/27 - Laboratório de Neurociências, Hospital das Clínicas, Faculdade de Medicina
LIM/27 - Laboratório de Neurociências, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
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- Heterogeneity of Cerebrospinal Fluid Biomarkers Profiles in Individuals with Distinct Levels of Cognitive Decline: A Cross-Sectional Study(2021) PAIS, Marcos; LOUREIRO, Julia; VALE, Vagner do; RADANOVIC, Marcia; TALIB, Leda; STELLA, Florindo; FORLENZA, OrestesBackground: Decreased cerebrospinal fluid (CSF) concentrations of the amyloid-beta (A beta), along with increased total (T-tau) and phosphorylated tau protein (P-tau), are widely accepted as core biomarkers of Alzheimer's disease (AD) pathology. Nonetheless, there are a few remaining caveats that still preclude the full incorporation of AD biomarkers into clinical practice. Objective: To determine the frequency of clinical-biological mismatches in a clinical sample of older adults with varying degrees of cognitive impairment. Methods: 204 participants were enrolled for a cross-sectional assessment and allocated into diagnostic groups: probable AD (n = 60, 29.4%); MCI (n = 84, 41.2%); or normal cognition (NC, n = 60, 29.4%). CSF concentrations of A beta(42), T-tau, and (181)Thr-P-tau were determined, and A beta(42)/P-tau ratio below 9.53 was used as a proxy of AD pathology. The AT(N) classification was further used as a framework to ascertain the biological evidence of AD. Results: The majority (73.7%) of patients in the AD group had the A beta(42)/P-tau ratio below the cut-off score for AD, as opposed to a smaller proportion in the MCI (42.9%) and NC (23.3%) groups. In the latter, 21 subjects (35%) were classified as A+, 28 (46.7%) as T+, and 23 (38.3%) as N+. In the AD group, 66.7% of the cases were classified as A+, 78.3% as T+, and 80% as N+. Conclusion: Analysis of CSF biomarkers was able to discriminate between AD, MCI, and NC. However, clinical-biological mismatches were observed in a non-negligible proportion of cases.
bookPart Proteômica e neuroquímica(2021) JOAQUIM, Helena Passarelli Giroud; COSTA, Alana Caroline; SARNO, Tamires Alves; TALIB, Leda LemebookPart Exames laboratoriais, marcadores genéticos e biomarcadores humorais(2021) TALIB, Leda Leme; PAIS, Marcos Vasconcelos; DINIZ, Breno; BRAM, Jessyka Maria de França; JOAQUIM, Helena Passarelli Giroud; COSTA, Alana Caroline; FORLENZA, Orestes Vicente- Increased PLA(2) activity in individuals at ultra-high risk for psychosis(2021) TALIB, Leda L.; COSTA, Alana C.; JOAQUIM, Helena P. G.; PEREIRA, Cicero A. C.; BILT, Martinus T. van de; LOCH, Alexandre A.; GATTAZ, Wagner F.Phospholipase A(2) is the main enzyme in the metabolism of membrane phospholipids. It comprises a family of enzymes divided into iPLA(2), cPLA(2) and sPLA(2). Studies have reported increased PLA(2) activity in psychotic patients, which suggests an accelerated breakdown of membrane phospholipids. In the present study we investigated whether increased PLA(2) activity is also present in individuals at ultra-high risk (UHR) for psychosis. One-hundred fifty adults were included in this study (85 UHR and 65 controls). UHR was assessed using the ""structured interview for prodromal syndromes"". PLA(2) activity was determined in platelets by a radio-enzymatic assay. We found in UHR individuals increased activities of iPLA(2) (p < 0.001) and cPLA(2) (p = 0.012) as compared to controls. No correlations were found between socio-demographic and clinical parameters and PLA(2) activity. Our findings suggest that increased PLA(2) activities may be useful as a biological risk-marker for psychotic disorders.
- AD-Related CSF Biomarkers Across Distinct Levels of Cognitive Impairment: Correlations With Global Cognitive State(2021) IBARRA, Romel; RADANOVIC, Marcia; V, Marcos Pais; TALIB, Leda L.; FORLENZA, Orestes V.Aim: Associations between cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD) with the severity of cognitive impairment are unclear. We examined the correlations between CSF biomarkers and cognitive performance in the AD continuum. Methods: We studied 143 elderly patients: cognitively unimpaired (n = 51), mild cognitive impairment (MCI) amnestic (n = 55) and nonamnestic (n = 20), and mild AD (n = 17) assessed with the Cambridge Cognitive Test (CAMCOG). We correlated total CAMCOG and its subdomains with CSF A beta 42, T-tau, p-tau levels, and A beta 42/p-tau. Results: In the total sample, T-tau and A beta 42/p-tau correlated with the total CAMCOG (P< .01); all biomarkers correlated with memory (P< .001); T-tau correlated with language (P< .01). Conclusion: Memory and T-tau levels may be the most suitable parameters to reflect cognitive/CSF biomarker correlations. At present, such correlations are of little use in routine clinical practice.