Navegando por Palavras-chave "Subtypes"

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    Attention-deficit/hyperactivity disorder dimensionality: the reliable 'g' and the elusive 's' dimensions
    (Springer, 2016) Wagner, Flavia; Martel, Michelle M.; Cogo-Moreira, Hugo [UNIFESP]; Moreira Maia, Carlos Renato; Pan, Pedro Mario [UNIFESP]; Rohde, Luis Augusto; Salum, Giovanni Abrahao
    The best structural model for attention-deficit/hyperactivity disorder (ADHD) symptoms remains a matter of debate. The objective of this study is to test the fit and factor reliability of competing models of the dimensional structure of ADHD symptoms in a sample of randomly selected and high-risk children and pre-adolescents from Brazil. Our sample comprised 2512 children aged 6-12 years from 57 schools in Brazil. The ADHD symptoms were assessed using parent report on the development and well-being assessment (DAWBA). Fit indexes from confirmatory factor analysis were used to test unidimensional, correlated, and bifactor models of ADHD, the latter including "g" ADHD and "s" symptom domain factors. Reliability of all models was measured with omega coefficients. A bifactor model with one general factor and three specific factors (inattention, hyperactivity, impulsivity) exhibited the best fit to the data, according to fit indices, as well as the most consistent factor loadings. However, based on omega reliability statistics, the specific inattention, hyperactivity, and impulsivity dimensions provided very little reliable information after accounting for the reliable general ADHD factor. Our study presents some psychometric evidence that ADHD specific ("s") factors might be unreliable after taking common ("g" factor) variance into account. These results are in accordance with the lack of longitudinal stability among subtypes, the absence of dimension-specific molecular genetic findings and non-specific effects of treatment strategies. Therefore, researchers and clinicians might most effectively rely on the "g" ADHD to characterize ADHD dimensional phenotype, based on currently available symptom items.
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    Attention-deficit/hyperactivity disorder dimensionality: the reliable 'g' and the elusive 's' dimensions
    (Springer, 2016) Wagner, Flavia; Martel, Michelle M.; Cogo-Moreira, Hugo [UNIFESP]; Moreira Maia, Carlos Renato; Pan, Pedro Mario [UNIFESP]; Rohde, Luis Augusto; Salum, Giovanni Abrahao
    The best structural model for attention-deficit/hyperactivity disorder (ADHD) symptoms remains a matter of debate. The objective of this study is to test the fit and factor reliability of competing models of the dimensional structure of ADHD symptoms in a sample of randomly selected and high-risk children and pre-adolescents from Brazil. Our sample comprised 2512 children aged 6-12 years from 57 schools in Brazil. The ADHD symptoms were assessed using parent report on the development and well-being assessment (DAWBA). Fit indexes from confirmatory factor analysis were used to test unidimensional, correlated, and bifactor models of ADHD, the latter including "g" ADHD and "s" symptom domain factors. Reliability of all models was measured with omega coefficients. A bifactor model with one general factor and three specific factors (inattention, hyperactivity, impulsivity) exhibited the best fit to the data, according to fit indices, as well as the most consistent factor loadings. However, based on omega reliability statistics, the specific inattention, hyperactivity, and impulsivity dimensions provided very little reliable information after accounting for the reliable general ADHD factor. Our study presents some psychometric evidence that ADHD specific ("s") factors might be unreliable after taking common ("g" factor) variance into account. These results are in accordance with the lack of longitudinal stability among subtypes, the absence of dimension-specific molecular genetic findings and non-specific effects of treatment strategies. Therefore, researchers and clinicians might most effectively rely on the "g" ADHD to characterize ADHD dimensional phenotype, based on currently available symptom items.
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    Avaliação da epidemia do vírus da imunodeficiência humana tipo 1 (HIV-1) na região sul do Brasil
    (Universidade Federal de São Paulo (UNIFESP), 2021) Camargo, Michelle [UNIFESP]; Diaz, Ricardo Sobhie [UNIFESP]; Universidade Federal de São Paulo
    Introduction: The high genetic diversity of HIV-1 has profound implications for viral adaptive and evolutionary capabilities. The intense genetic variability characterized by the population model of HIV-1 suffers events of drastic reduction of genetic variants less adapted to the selective pressures of the host and among the viruses themselves within the population, causing a constant oscillation of the viral genetic characteristics in a population. Viral populations have developed mechanisms to compensate for the negative effects of genetic “bottlenecks”, random events capable of reducing the size of the effective population to the point that only a few representatives of the original population are able to form a new resulting population. The phenomenon of recombination contributes to the increase of genetic diversity in the viral population and the recombination homogenizes that same population after countless mutational events in order to prevent viral extinction, and both hypotheses leave it open if the recombination confers functional advantages to the viruses that experience it. Objectives: To evaluate the genetic diversity of the HIV-1 protease, reverse transcriptase (gen pol), V3 and gp41 regions (gene env) among individuals with a recent diagnosis of infection in the Southern region of Brazil. Methods: Extraction, reverse transcription, amplification and genetic sequencing of 808 newly diagnosed plasma samples followed by phylogenetic analyzes to assess recombination, detection of selective pressure, tropism, transmitted resistance, genetic diversity, and mosaicism were performed. Results: The selective pressure analyzes based on a pairwise measurement (Nei & Gojobori) we found a selective pressure with values of w above 1 only in the recombinants of the pol region and in the subtypes B, C and F of the gp41 region. Subtype C appears to retain the R5 phenotype. The resistance transmitted to ARVs seems to be present, even before the medication is used by the infected individual, although relatively low. The genetic diversity values in the pol region were higher than one would expect to find in non-strongly immunogenic genes such as pol. Predominance of subtype C was observed in the analyzed viral regions, followed by subtype B, subtype F for two regions, however, for the pol region the predominance of sequences that showed intrasubtype recombination was greater than the number of F sequences. The mapping of recombination breakpoints an attempt was made to identify peculiar molecular characteristics that may confer adaptive advantages. Conclusion: A predominance of subtype C and recombinants (especially B/C) in the Southern region of Brazil is suggested, predominantly with tropism R5, with the frequency of resistance transmitted being relatively low, as well as suggesting a slight difference in the selective pressures suffered in the regions evaluated, however, the high evidence of recombinant suggests the occurrence of recombination events that could represent one of these mechanisms for re-homogenizing the viral population, reestablishing ideal fitness in order to avoid viral extinction.
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    Is there a metabolic-mood syndrome? A review of the relationship between obesity and mood disorders
    (Elsevier B.V., 2015-05-01) Mansur, Rodrigo B. [UNIFESP]; Brietzke, Elisa [UNIFESP]; McIntyre, Roger S.; Univ Toronto; Universidade Federal de São Paulo (UNIFESP)
    Obesity and mood disorders are highly prevalent and co-morbid. Epidemiological studies have highlighted the public health relevance of this association, insofar as both conditions and its co-occurrence are associated with a staggering illness-associated burden. Accumulating evidence indicates that obesity and mood disorders are intrinsically linked and share a series of clinical, neurobiological, genetic and environmental factors. the relationship of these conditions has been described as convergent and bidirectional; and some authors have attempted to describe a specific subtype of mood disorders characterized by a higher incidence of obesity and metabolic problems. However, the nature of this association remains poorly understood. There are significant inconsistencies in the studies evaluating metabolic and mood disorders; and, as a result, several questions persist about the validity and the generalizability of the findings. An important limitation in this area of research is the noteworthy phenotypic and pathophysiological heterogeneity of metabolic and mood disorders. Although clinically useful, categorical classifications in both conditions have limited heuristic value and its use hinders a more comprehensive understanding of the association between metabolic and mood disorders. A recent trend in psychiatry is to move toward a domain specific approach, wherein psychopathology constructs are agnostic to DSM-defined diagnostic categories and, instead, there is an effort to categorize domains based on pathogenic substrates, as proposed by the National Institute of Mental Health (NIMH) Research Domain Criteria Project (RDoC). Moreover, the substrates subserving psychopathology seems to be unspecific and extend into other medical illnesses that share in common brain consequences, which includes metabolic disorders. Overall, accumulating evidence indicates that there is a consistent association of multiple abnormalities in neuropsychological constructs, as well as correspondent brain abnormalities, with broad-based metabolic dysfunction, suggesting, therefore, that the existence of a metabolic-mood syndrome is possible. Nonetheless, empirical evidence is necessary to support and develop this concept. Future research should focus on dimensional constructs and employ integrative, multidisciplinary and multimodal approaches. (C) 2015 Elsevier B.V. All rights reserved.
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    Otimização de técnica de PCR em tempo real para detecção das regiões pol e env dos subtipos B e F de HIV-1 e triagem de seus recombinantes
    (Universidade Federal de São Paulo (UNIFESP), 2009-01-28) Teixeira, Daniela [UNIFESP]; Diaz, Ricardo Sobhie [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Background: The discovery of 42 HIV-1 circulating recombinant forms (CRF) together with the innumerous unique HIV recombinants forms, makes clear the role of genetic recombination for the epidemic. In Brazil, clades B, F, and C co-circulate, with 5 recently described CRFs. Real Time PCR is a rapid and reliable tool capable of detecting different HIV-1 subtypes and recombinant profiles. Objective: The aim of this study was to develop real time PCR systems in order to detect the Brazilian CRF_28 and CRF_29, which are B/F recombinants, as well as detect B/F recombinants generated by in vitro competition assays. In future, these systems should be able to discriminate subtypes in clinical surveys. Methodology: MT-4 cells were separately infected with the viral strains BZ167 (subtype B) and BR020 (subtype F), and supernatant was collected in order to optimizing the real time PCR systems (TaqMan®) developed to detect the subtype profile of different genomic regions, including pol gene (protease, reverse transcriptase, integrase) and env gene (gp120 and gp41). The designed primers should be able to equally amplify the subtype B and F, which should be discriminated by subtype-specific probes. For future validation of these PCR systems, 157 clinical samples from the city of Santos were sequenced and phylogeneticaly analyzed in order to perform the clade assignment with Neighbor-Joining algorithm (Phylip software package v3.5). Results: The designed systems were able to differentiate the utilized viral strains. The estimated efficiencies for each system, for each probe, subtypes B and F separately, were respectively: 80,97 and 85,16% for protease region; 89,80 and 75,09% for reverse transcriptase region; 80,90% and 83,83% for integrase region; 93,49 and 98,93% for gp120 region; and 88,45 and 80,19% for gp41 region. For the co-infected cell culture, the detection of each subtype was performed in the first and fifth passages. Generally, the initial concentration of subtype B appeared to have decreased, some of them becoming undetectable, whereas subtype F seemed to increase with the passages, for protease, reverse transcriptase, gp120 and gp41 regions. The integrase region was an exception, since only the subtype B was detected, with increasing Cycle threshold (Ct) values over time. Sequencing results revealed that 65 out of 157 samples had the subtype profile defined for all regions. 43 out of 71 were defined as B, whereas 3 were F in all regions. 12 samples presented the CRF_28 profile, and 9 samples presented the CRF_29 profile. There were no subtype C samples in any genomic regions analyzed. Conclusion: The use of real time PCR technique for identification of fragments’ subtypes in cell culture and for evaluation of replicative dynamics of recombination in co-infected cultures warrants its potential use in future in vivo surveys. This methodology proved to be efficient, fast, less cumbersome and less expensive than DNA sequencing. The newly designed systems performed for supernatant of competition assays had suggested a divergent distribution of subtypes for the different regions, which reflects the possibility of genetic recombination. Results from clinical samples revealed a high prevalence of CRF_28/29 in this geographic region, thus reflecting the resulting consequence of different co-circulating strains and pointing to the need for a careful surveillance.