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The hyperphosphorylation of tau is a central mechanism in the pathogenesis of Alzheimer’s disease (AD). Lithium is a potent inhibitor of glycogen synthase kinase-3beta (GSK3β), the most important tau kinase in neurons, and may also affect tau phosphorylation by modifying the expression and/or activity of other kinases, such as protein kinase A (PKA), Akt (PKB), and calcium calmodulin kinase-II (CaMKII). The aim of the present study is to determine the effect of chronic lithium treatment on the protein expression of tau and its major kinases in cortical and hippocampal neurons, at distinct working concentrations. Primary cultures of cortical and hippocampal neurons were treated with sub-therapeutic (0.02 mM and 0.2 mM) and therapeutic (2 mM) concentrations of lithium for 7 days. Protein expression of tau and tau-kinases was determined by immunoblotting. An indirect estimate of GSK3β activity was determined by the GSK3β ratio (rGSKβ). Statistically significant increments in the protein expression of tau and CaMKII were observed both in cortical and hippocampal neurons treated with subtherapeutic doses of lithium. GSK3β activity was increased in cortical, but decreased in hippocampal neurons. Distinct patterns of changes in the expression of the remaining tau tau-kinases were observed: in cortical neurons, lithium treatment was associated with consistent decrements in Akt and PKA, whereas hippocampal neurons displayed increased protein expression of Akt and decreased PKA. Our results suggest that chronic lithium treatment may yield distinct biological effects depending on the concentration range, with regional specificity. We further suggest that hippocampal neurons may be more sensitive to the effect of lithium, presenting with changes in the expression of tau-related proteins at subtherapeutic doses, which may not be mirrored by the effects observed in cortical neurons.

The hyperphosphorylation of tau is a central mechanism in the pathogenesis of Alzheimer's disease (AD). Lithium is a potent inhibitor of glycogen synthase kinase-3beta (GSK3β), the most important tau kinase in neurons, and may also affect tau phosphorylation by modifying the expression and/or activity of other kinases, such as protein kinase A (PKA), Akt (PKB), and calcium calmodulin kinase-II (CaMKII). The aim of the present study is to determine the effect of chronic lithium treatment on the protein expression of tau and its major kinases in cortical and hippocampal neurons, at distinct working concentrations. Primary cultures of cortical and hippocampal neurons were treated with sub-therapeutic (0.02 mM and 0.2 mM) and therapeutic (2 mM) concentrations of lithium for 7 days. Protein expression of tau and tau-kinases was determined by immunoblotting. An indirect estimate of GSK3β activity was determined by the GSK3β ratio (rGSKβ). Statistically significant increments in the protein expression of tau and CaMKII were observed both in cortical and hippocampal neurons treated with subtherapeutic doses of lithium. GSK3β activity was increased in cortical, but decreased in hippocampal neurons. Distinct patterns of changes in the expression of the remaining tau tau-kinases were observed: in cortical neurons, lithium treatment was associated with consistent decrements in Akt and PKA, whereas hippocampal neurons displayed increased protein expression of Akt and decreased PKA. Our results suggest that chronic lithium treatment may yield distinct biological effects depending on the concentration range, with regional specificity. We further suggest that hippocampal neurons may be more sensitive to the effect of lithium, presenting with changes in the expression of tau-related proteins at subtherapeutic doses, which may not be mirrored by the effects observed in cortical neurons.

To determine the frequency and features of psychiatric morbidity in a cross-section of 38 outpatients with neurocysticercosis.Diagnosis of neurocysticercosis was established by CT scan, MRI and CSF analysis. Psychiatric diagnoses were made by using the Present State Examination and the Schedule for Affective Disorders and Schizophrenia. Lifetime version; cognitive state was assessed by Mini-Mental State Examination and StrubBlack's Mental Status Examination.Depression was the most frequent psychiatric diagnosis (52.6%) as shown by PSE. Active disease and intracranial hypertension were associated with higher psychiatric morbidity, and previous history of mood disorders was strongly related to current depression.Depression syndromes are frequent in patients with neurocysticercosis. The extent to which organic mechanisms related to brain lesions may underlie the observed mental changes is yet unclear, though the similar sex distribution of patients with and without depression, as well as the above mentioned correlations, provide further evidence of the role played by organic factors in the cause of these syndromes. The results of this study are discussed in the light of the data available for other organic psychiatric disorders.

Brazil has been experiencing a steady increase in the elderly population during the past few years, and as a result old age health-related problems are increasing continuously in number. Psychiatric symptoms are among the most prevalent health problems of the elderly and are an important source of distress for patients and carers, being also associated with significant growth in the costs and demand for the provision of health care services. This study aimed to investigate the prevalence of mental health problems among the elderly attending a regional primary care unit in the city of São Paulo, Brazil. A total of 351 patients older than 60 were assessed during a 6-month period with the SRQ-20 (a scale for the detection of minor psychiatric problems), four questions on psychotic symptoms. AMTS (a scale for the assessment of cognitive functioning) and CAGE (a scale for the assessment of alcoholism); demographic variables were also recorded. Subjects' mean age was 71.22 (CI = 70.51-71.92) and 83.5% were female. Thirty-two per cent of subjects were considered 'cases' as they scored more than 7 on the SRQ-20 (26.8% of total), or more than 1 on the CAGE (1.4% of total), or at least 1 on the questions assessing psychotic symptoms (12.2% of total). There was a significant excess of women among those found to suffer from psychiatric problems (90.1% vs 80.4%). Cases were also more likely to be illiterate (23.4% vs 12.1%) and to have a lower income (2.21 vs 4.01 minimum wages). Depressive symptoms and tension were highly prevalent (72.9% of subjects). Somatic complaints and signs of inefficient functioning were also common (50.4% and 45.9% respectively). Only five patients answered affirmatively two or more CAGE questions and 12.2% scored at least 1 on the questions assessing psychotic symptoms. Cognitive deficit, as determined by the AMTS, was observed in 13.4% of the sample and was associated with ageing, being illiterate and having higher total SRQ-20 scores. We suggest, that the organization of health care services should take into account the needs of this population, and should also emphasize professional training for the correct assessment and treatment of the most frequent mental health problems in old age.