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1.
Epidemiol Psychiatr Sci ; 33: e21, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38576239

RESUMEN

AIMS: The effectiveness and cost-effectiveness of early intervention for psychosis (EIP) services are well established in high-income countries but not in low- and middle-income countries (LMICs). Despite the scarcity of local evidence, several EIP services have been implemented in LMICs. Local evaluations are warranted before adopting speciality models of care in LMICs. We aimed to estimate the cost-effectiveness of implementing EIP services in Brazil. METHODS: A model-based economic evaluation of EIP services was conducted from the Brazilian healthcare system perspective. A Markov model was developed using a cohort study conducted in São Paulo. Cost data were retrieved from local sources. The outcome of interest was the incremental cost-effectiveness ratio (ICER) measured as the incremental costs over the incremental quality-adjusted life-years (QALYs). Sensitivity analyses were performed to test the robustness of the results. RESULTS: The study included 357 participants (38% female), with a mean (SD) age of 26 (7.38) years. According to the model, implementing EIP services in Brazil would result in a mean incremental cost of 4,478 Brazilian reals (R$) and a mean incremental benefit of 0.29 QALYs. The resulting ICER of R$ 15,495 (US dollar [USD] 7,640 adjusted for purchase power parity [PPP]) per QALY can be considered cost-effective at a willingness-to-pay threshold of 1 Gross domestic product (GDP) per capita (R$ 18,254; USD 9,000 PPP adjusted). The model results were robust to sensitivity analyses. CONCLUSIONS: This study supports the economic advantages of implementing EIP services in Brazil. Although cultural adaptations are required, these data suggest EIP services might be cost-effective even in less-resourced countries.


Asunto(s)
Países en Desarrollo , Trastornos Psicóticos , Humanos , Femenino , Adulto , Masculino , Análisis Costo-Beneficio , Estudios de Cohortes , Brasil , Trastornos Psicóticos/terapia
3.
Schizophr Res Cogn ; 12: 20-28, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29552509

RESUMEN

BACKGROUND: The lack of efficacy of pharmacological treatments for cognitive and negative symptoms in schizophrenia highlights the need for new interventions. We investigated the effects of tDCS on working memory and negative symptoms in patients with schizophrenia. METHOD: Double-blinded, randomized, sham-controlled clinical trial, investigating the effects of 10 sessions of tDCS in schizophrenia subjects. Stimulation used 2 mA, for 20 min, with electrodes of 25 cm2 wrapped in cotton material soaked in saline solution. Anode was positioned over the left DLPFC and the cathode in the contralateral area. Twenty-four participants were assessed at baseline, after intervention and in a three-months follow-up. The primary outcome was the working memory score from MATRICS and the secondary outcome the negative score from PANSS. Data were analyzed using generalized estimating equations. RESULTS: We did not find group ∗ time interaction for the working memory (p = 0.720) score or any other cognitive variable (p > 0.05). We found a significant group ∗ time interaction for PANSS negative (p < 0.001, d = 0.23, CI.95 = -0.59-1.02), general (p = 0.011) and total scores (p < 0.001). Exploratory analysis of PANSS 5 factors suggests tDCS effect on PANSS negative (p = 0.012), cognitive (p = 0.016) and depression factors (p = 0.029). CONCLUSION: The results from this trial highlight the therapeutic effects of tDCS for treatment of persistent symptoms in schizophrenia, with reduction of negative symptoms. We were not able to confirm the superiority of active tDCS over sham to improve working memory performance. Larger sample size studies are needed to confirm these findings.

4.
Nat Commun ; 9(1): 1221, 2018 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-29572537

RESUMEN

The understanding of interactions between electrons and phonons in atomically thin heterostructures is crucial for the engineering of novel two-dimensional devices. Electron-phonon (el-ph) interactions in layered materials can occur involving electrons in the same layer or in different layers. Here we report on the possibility of distinguishing intralayer and interlayer el-ph interactions in samples of twisted bilayer graphene and of probing the intralayer process in graphene/h-BN by using Raman spectroscopy. In the intralayer process, the el-ph scattering occurs in a single graphene layer and the other layer (graphene or h-BN) imposes a periodic potential that backscatters the excited electron, whereas for the interlayer process the el-ph scattering occurs between states in the Dirac cones of adjacent graphene layers. Our methodology of using Raman spectroscopy to probe different types of el-ph interactions can be extended to study any kind of graphene-based heterostructure.

5.
Schizophr Res ; 195: 591-593, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28882685

RESUMEN

BACKGROUND: Cognitive impairments in schizophrenia are strongly correlated to functional outcome and recovery rates, with no pharmacological agent approved for its treatment. Neurofeedback has emerged as a non-pharmacological approach to enhance neuroplasticity, which consists in inducing voluntary control of brain responses through operant conditioning. METHOD: The effects of hemoencephalography neurofeedback (HEG-NFBK) in 4 brain sites (F7, Fp1, Fp2 and F8) was studied in 8 patients with schizophrenia (SCH, mean age 36.5±9.98) and 12 health controls (mean age 32.17±5.6). We analyzed groups' performance (10 sessions) and cognitive differences in 3 time points (baseline, after training and follow-up) with generalized estimated equations. For SCH we also evaluate the impact on psychopathology. RESULTS: We found a group∗time interaction for HEG-NFBK performance in the left hemisphere sites (F7 an Fp1) and a near-to-significant in the right frontotemporal region (F8), with no group differences and a significant time effect. Most of cognitive domains improved after intervention, including information processing speed, attention processing, working memory, executive functioning, verbal and visual learning. No group∗time interaction was found. Results suggest that both groups benefit from HEG-NFBK training regardless of cognitive differences at baseline. No significant time effects were found for Calgary and PANSS total scale and subscales (positive, negative neither general). CONCLUSION: To our knowledge, this is the first controlled trial showing effects of NFBK on cognitive performance improvement in schizophrenia. Further research investigating the effects of HEG-NFBK training in schizophrenia should be performed.


Asunto(s)
Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/rehabilitación , Neurorretroalimentación/métodos , Esquizofrenia/complicaciones , Psicología del Esquizofrénico , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estadísticas no Paramétricas
6.
Brain Imaging Behav ; 11(3): 808-817, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27169540

RESUMEN

Brain development during childhood and early adolescence is characterized by global changes in brain architecture. Neuroimaging studies have revealed overall decreases in cortical thickness (CT) and increases in fractional anisotropy (FA). Furthermore, previous studies have shown that certain cortical regions display coordinated growth during development. However, there is significant heterogeneity in the timing and speed of these developmental transformations, and it is still unclear whether white and grey matter changes are co-localized. In this multimodal neuroimaging study, we investigated the relationship between grey and white matter developmental changes and asynchronous maturation within brain regions in 249 normally developing children between the ages 7-14. We used structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) to analyze CT and FA, respectively, as well as their covariance across development. Consistent with previous studies, we observed overall cortical thinning with age, which was accompanied by increased FA. We then compared the coordinated development of grey and white matter as indexed by covariance measures. Covariance between grey matter regions and the microstructure of white matter tracts connecting those regions were highly similar, suggesting that coordinated changes in the cortex were mirrored by coordinated changes in their respective tracts. Examining within-brain divergent trajectories, we found significant structural decoupling (decreased covariance) between several brain regions and tracts in the 9- to 11-year-old group, particularly involving the forceps minor and the regions that it connects to. We argue that this decoupling could reflect a developmental pattern within the prefrontal region in 9- and 11-year-old children, possibly related to the significant changes in cognitive control observed at this age.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/crecimiento & desarrollo , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/crecimiento & desarrollo , Adolescente , Niño , Estudios Transversales , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Imagen Multimodal , Tamaño de los Órganos
7.
Psychol Med ; 47(2): 255-266, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27697085

RESUMEN

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is frequently associated with poorer reading ability; however, the specific neuropsychological domains linking this co-occurrence remain unclear. This study evaluates information-processing characteristics as possible neuropsychological links between ADHD symptoms and RA in a community-based sample of children and early adolescents with normal IQ (⩾70). METHOD: The participants (n = 1857, aged 6-15 years, 47% female) were evaluated for reading ability (reading single words aloud) and information processing [stimulus discriminability in the two-choice reaction-time task estimated using diffusion models]. ADHD symptoms were ascertained through informant (parent) report using the Development and Well-Being Assessment (DAWBA). Verbal working memory (VWM; digit span backwards), visuospatial working memory (VSWM, Corsi Blocks backwards), sex, socioeconomic status, and IQ were included as covariates. RESULTS: In a moderated mediation model, stimulus discriminability mediated the effect of ADHD on reading ability. This indirect effect was moderated by age such that a larger effect was seen among younger children. CONCLUSION: The findings support the hypothesis that ADHD and reading ability are linked among young children via a neuropsychological deficit related to stimulus discriminability. Early interventions targeting stimulus discriminability might improve symptoms of inattention/hyperactivity and reading ability.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Discriminación en Psicología/fisiología , Dislexia/fisiopatología , Reconocimiento Visual de Modelos/fisiología , Lectura , Adolescente , Niño , Femenino , Humanos , Masculino
8.
Transl Psychiatry ; 6(10): e908, 2016 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-27701407

RESUMEN

Psychotic disorders affect ~3% of the general population and are among the most severe forms of mental diseases. In early stages of psychosis, clinical aspects may be difficult to distinguish from one another. Undifferentiated psychopathology at the first-episode of psychosis (FEP) highlights the need for biomarkers that can improve and refine differential diagnosis. We investigated gene expression differences between patients with FEP-schizophrenia spectrum (SCZ; N=53) or FEP-Mania (BD; N=16) and healthy controls (N=73). We also verified whether gene expression was correlated to severity of psychotic, manic, depressive symptoms and/or functional impairment. All participants were antipsychotic-naive. After the psychiatric interview, blood samples were collected and the expression of 12 psychotic-disorder-related genes was evaluated by quantitative PCR. AKT1 and DICER1 expression levels were higher in BD patients compared with that in SCZ patients and healthy controls, suggesting that expression of these genes is associated more specifically to manic features. Furthermore, MBP and NDEL1 expression levels were higher in SCZ and BD patients than in healthy controls, indicating that these genes are psychosis related (independent of diagnosis). No correlation was found between gene expression and severity of symptoms or functional impairment. Our findings suggest that genes related to neurodevelopment are altered in psychotic disorders, and some might support the differential diagnosis between schizophrenia and bipolar disorder, with a potential impact on the treatment of these disorders.


Asunto(s)
Trastorno Bipolar/genética , Regulación de la Expresión Génica/genética , Trastornos Psicóticos/genética , Esquizofrenia/genética , Psicología del Esquizofrénico , Adulto , Proteínas Portadoras/genética , Estudios de Casos y Controles , ARN Helicasas DEAD-box/genética , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Proteína Básica de Mielina/genética , Proteínas Proto-Oncogénicas c-akt/genética , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Psicometría , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/psicología , Valores de Referencia , Ribonucleasa III/genética , Esquizofrenia/diagnóstico , Estadística como Asunto , Adulto Joven
9.
Acta Psychiatr Scand ; 133(2): 122-132, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26139469

RESUMEN

OBJECTIVE: To investigate the association between peripheral biomarkers and child psychopathology in a large community sample. METHOD: A total of 625 aged 6- to 13-year old subjects were recruited from a community school-based study. Psychopathology was assessed using the Child Behaviour Checklist (CBCL). Psychiatric diagnosis was evaluated using the Development and Well-Being Assessment. The following biomarkers were examined in peripheral blood: brain-derived neurotrophic factor, cytokines (IL-2, IL-4, IL-6, IL-10, IL-17, IFN-g, and TNF-α), chemokines (eotaxin/CCL11, IP-10, MCP-1), cytokine receptors (sTNFR1 and sTNFR2), and the oxidative stress marker TBARS. RESULTS: We found significant associations between sTNFR2, eotaxin/CCL11 and CBCL total score, as well as with specific dimensions of psychopathology. There were different patterns of association between these biomarkers and psychological and behavioural symptoms in children with and without a mental disorder. TBARS, IL-6 and MCP-1 were more specific to some clusters of symptoms in children with a psychiatric diagnosis. CONCLUSION: Our data support the potential use of biomarkers, especially those involved in immune-inflammatory pathways, in investigating neurodevelopmental psychopathology. Their association with different dimensions of symptoms might be of useful when analyzing illness severity and clusters of symptoms within specific disorders.

10.
Transl Psychiatry ; 5: e691, 2015 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-26645626

RESUMEN

In schizophrenia (SCZ), higher angiotensin I-converting enzyme (ACE) levels have been reported in patient's blood and cerebrospinal fluid (CSF). Hereby, we propose to explore whether the ACE activity levels are associated to cognitive performance in SCZ. Seventy-two patients with SCZ or schizoaffective disorder diagnosis, and 69 healthy controls (HCs) underwent a cognitive battery with parallel collection of peripheral blood samples to measure ACE activity. Significant higher ACE activity levels were confirmed in the plasma of SCZ patients compared with HCs (Student's t=-5.216; P<0.001). ACE activity significantly correlated to Hopkins delayed recall measures (r=-0.247; P=0.004) and Hopkins total (r=-0.214; P=0.012). Subjects grouped as high ACE activity (above average) had worse performance compared with low ACE activity level group for Hopkins delayed recall measure, even after correction for clinical condition, age, gender and years of education (P=0.029). The adjusted R squared for this final model was 0.343. This result was evident only comparing extreme groups for ACE activity, when splitting the sample in three groups with similar number of subjects. To clarify this finding, we performed an evaluation of the cognitive performance of transgenic mice with three copies of ACE gene in novel object recognition (NOR) test, which showed that such animals presented impairment in NOR (P<0.05) compared with two copies of wild-type animals. The results observed in SCZ patients and animal model suggest both the association of ACE to cognitive deficits in SCZ. This finding may support the evaluation of novel treatment protocols and/or of innovative drugs for specific intervention of cognitive deficits in SCZ envisioning concomitant ACE activity and behavior evaluations.


Asunto(s)
Trastornos del Conocimiento/sangre , Trastornos del Conocimiento/complicaciones , Peptidil-Dipeptidasa A/sangre , Esquizofrenia/sangre , Esquizofrenia/complicaciones , Adolescente , Adulto , Anciano , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Adulto Joven
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