Incidence and risk factors for anxiety disorders in young adults: A population-based prospective cohort study.

Anxiety disorders are among the most common psychiatric disorders in the general population. Our objective was to describe the cumulative incidence and risk factors of anxiety disorders, including obsessive-compulsive disorder (OCD) and posttraumatic stress disorder (PTSD), in a follow-up of young adults over a five-year period. This is a prospective cohort conducted in two waves. The first took place from 2007 to 2009, in which 1,560 young adults aged between 18 and 24 years were evaluated using the Mini-International Neuropsychiatric Interview (MINI). Subjects were invited to participate in the second wave, which wave took place from 2012 to 2014, where 1,244 young adults were evaluated using the MINI-Plus. Our findings showed a cumulative incidence of 10.9% for any anxiety disorder, 6.5% for generalized anxiety disorder, 6.0% for agoraphobia, 2.0% for OCD, 1.6% for panic disorder, 1.1% for social anxiety and 0.7% for PTSD. Being female and having had a depressive episode were risk factors to develop any anxiety disorder. We observed a high cumulative incidence of anxiety disorders in a population-based sample of young adults. Our data highlights the importance of the early identification of these disorders as this could lead to early illness detection, early illness management and a reduced burden of disease.

Suicide risk in people living with AIDS/HIV: the effect of childhood trauma is mediated by mental disorders and social vulnerability.

Suicide is an important problem in people living with HIV/AIDS (PLWHA). The importance of mental disorders and social vulnerability on suicidal behaviors is described in the literature; however, the impact of childhood traumatic events in this scenario is not clear. The aim of this study was to verify the mediation effect of mental disorder comorbidities and social vulnerability in association with childhood trauma intensity and suicide risk level. This cross-sectional study of HIV-positive outpatients was conducted in a specialized care service in the city of Pelotas in Southern Brazil. Sociodemographic data and HIV-related information were collected and the Childhood Trauma Questionnaire was applied. A total of 364 patients underwent psychiatric evaluation using MINI Plus including module C of suicide risk severity. Suicide risk was present in 39.3% of the sample. The relation between childhood traumatic events and the level of suicide risk is mediated by mental disorder comorbidities and socioeconomic vulnerability. Specific psychosocial interventions in PLWHA should consider the potential role of abusive traumatic experiences in the current mental health conditions and suicidal behaviors.

Mood disorders and prospective suicidality in young adults: a population-based cohort study.

OBJECTIVE: To assess the prospective associations of mood disorders and suicidality in a community sample of young adults from south Brazil. METHOD: Prospective population-based cohort study. Young adults (18-24 years old) were recruited and followed up on 5 years later; people were interviewed at their homes. Suicidality, as well as mood and anxiety disorders, was assessed using the Mini-International Neuropsychiatric Interview. The impact of mood episodes on suicidality was both evaluated when they occurred in the same wave (a current episode) and when suicidality occurred prospectively, with suicidality measured at follow-up (a past episode). RESULTS: The sample included 1560 young adults at baseline, with 1244 reassessed at follow-up (80.6%). Depressive episodes, both current and past, had a significant impact on suicidality in the final multivariable model. Manic episodes, however, were less consistently associated with suicidality. CONCLUSION: Depressive episodes have a strong, independent, and robust association with prospective suicidality. The association between manic episodes and suicidality, on the other hand, was dependent on the analysis and deserves further exploration.

Optical and transport properties correlation driven by amorphous/crystalline disorder in InP nanowires.

Indium phosphide nanowires with a single crystalline zinc-blend core and polycrystalline/amorphous shell were grown from a reliable route without the use of hazardous precursors. The nanowires are composed by a crystalline core covered by a polycrystalline shell, presenting typical lengths larger than 10 µm and diameters of 80-90 nm. Raman spectra taken from as-grown nanowires exhibited asymmetric line shapes with broadening towards higher wave numbers which can be attributed to phonon localization effects. It was found that optical phonons in the nanowires are localized in regions with average size of 3 nm, which seems to have the same order of magnitude of grain sizes in the polycrystalline shell. Regardless of the fact that the nanowires exhibit a crystalline core, any considerable degree of disorder can lead to a localized behaviour of carriers. In consequence, the variable range hopping was observed as the main transport instead of the usual thermal excitation mechanisms. Furthermore the hopping length was ten times smaller than nanowire cross-sections, confirming that the nanostructures do behave as a 3D system. Accordingly, the V-shape observed in PL spectra clearly demonstrates a very strong influence of the potential fluctuations on the exciton optical recombination. Such fluctuations can still be observed at low temperature regime, confirming that the amorphous/polycrystalline shell of the nanowires affects the exciton recombination in every laser power regime tested.

Depression and diagnosis of neurocognitive impairment in HIV-positive patients.

Neurocognitive impairment (NCI) is frequently observed in patients infected with human immunodeficiency virus (HIV) and results from the compromise of subcortical brain structures by the virus. The manifestations of NCI range from asymptomatic impairment to dementia. In addition to cognitive impairment resulting from HIV infection, other factors such as depression are associated with the loss of cognitive functions. The aim of this study was to estimate the prevalence of NCI in HIV-positive patients in a city in southern Brazil and to establish possible associations for the prevalence of NCI with HIV-related and other risk factors. This cross-sectional study of HIV-positive outpatients was conducted in a specialized care service in the city of Pelotas in Southern Brazil. Sociodemographic data and HIV-related information were collected, and all patients underwent psychiatric and neurocognitive evaluations. The prevalence of NCI among the 392 patients was 54.1% when tracked using the IHDS (International HIV Dementia Scale) and 36.2% when the IHDS was associated with a battery of complementary tests. A bivariate analysis suggested an association of NCI with gender, age, educational level, depression, current CD4 count and lowest CD4 count. The association of NCI with depression remained in the Poisson regression (PR=1.96, 95%CI=1.12-3.42). The prevalence of cognitive impairment in HIV-positive patients estimated in this study is in accordance with international and Brazilian data. Of the factors analyzed, depression showed the greatest evidence of association with neurocognitive loss. Based on our findings, the inclusion of instruments to evaluate depression in our services for patients with HIV and acquired immunodeficiency syndrome (AIDS) is recommended.

Depression and diagnosis of neurocognitive impairment in HIV-positive patients

Neurocognitive impairment (NCI) is frequently observed in patients infected with human immunodeficiency virus (HIV) and results from the compromise of subcortical brain structures by the virus. The manifestations of NCI range from asymptomatic impairment to dementia. In addition to cognitive impairment resulting from HIV infection, other factors such as depression are associated with the loss of cognitive functions. The aim of this study was to estimate the prevalence of NCI in HIV-positive patients in a city in southern Brazil and to establish possible associations for the prevalence of NCI with HIV-related and other risk factors. This cross-sectional study of HIV-positive outpatients was conducted in a specialized care service in the city of Pelotas in Southern Brazil. Sociodemographic data and HIV-related information were collected, and all patients underwent psychiatric and neurocognitive evaluations. The prevalence of NCI among the 392 patients was 54.1% when tracked using the IHDS (International HIV Dementia Scale) and 36.2% when the IHDS was associated with a battery of complementary tests. A bivariate analysis suggested an association of NCI with gender, age, educational level, depression, current CD4 count and lowest CD4 count. The association of NCI with depression remained in the Poisson regression (PR=1.96, 95%CI=1.12-3.42). The prevalence of cognitive impairment in HIV-positive patients estimated in this study is in accordance with international and Brazilian data. Of the factors analyzed, depression showed the greatest evidence of association with neurocognitive loss. Based on our findings, the inclusion of instruments to evaluate depression in our services for patients with HIV and acquired immunodeficiency syndrome (AIDS) is recommended.

Effects of AlGaAs cladding layers on the luminescence of GaAs/GaAs1-xBix/GaAs heterostructures.

The structural and optical properties of GaAs1-xBix quantum wells (QWs) symmetrically clad by GaAs barriers with and without additional confining AlGaAs layers are studied. It is shown that a GaAs/GaAs1-xBix/GaAs QW with x ~ 4% and well width of ~ 4 nm grown by molecular beam epitaxy demonstrates efficient photoluminescence (PL) that becomes significantly more thermally stable when a cladding AlGaAs layer is added to the QW structure. The PL behavior for temperatures between 10 and 300 K and for excitation intensities varying by seven orders of magnitude can be well described in terms of the dynamics of excitons including carrier capture in the QW layer, thermal emission and diffusion into the cladding barriers. Understanding the role of these processes in the luminescence of dilute GaAs1-xBix QW structures facilitates the creation of highly efficient devices with reduced thermal sensitivity and low threshold current.

A case of a 69, XXY infant with a survival to age 40 months

Triploidía es la presencia de un set completo extra de cromosomas, la misma que puede ser una contribución de padre o de madre. Triploidías se encuentran en aproximadamente 6% de abortos espontáneos y solamente 1% de las mismas llega a término. Los fetos triploides pueden clasificarse en: Tipo I que corresponde a fetos en los cuales el material viene del padre (diántricos). Este tipo presenta de mediana a moderado retardo en el crecimiento así como molas hidatidiformes. El tipo II, en el cual el complemento extra viene de la madre y presentan un retardo intrauterino severo y asimétrico (digénico). La taza de supervivencia de éstos últimos es más alta que en el caso anterior y hasta el momento no se conoce un caso de triploidía con una supervivencia mayor a los 312 días. En el presente estudio reportamos a un infante masculino quien sobreviviera hasta los 40 meses de edad. El paciente nació de una madre saludable de 29 años de edad, con 30 semanas de gestación. Este paciente fue admitido a la unidad de cuidados intensivos (NICU), por presentar problemas de respiración. Los valores normales de 7-dehy drocolesterol excluyendo el hecho de que se tratara del síndrome de Smith-Lemli-Opitz. Se ordenaron realizar estudios citogenéticas debido a los rasgos dismórficos del paciente. El estudio citogenética de este paciente arrojó un cariotipo de 69,XXY sin evidencia de mosaicismo. Los hallazgos clínicos así como el tiempo extraordinariamente largo de sobrevivencia son sugestivos de una triploidía de origen digénico.