Contributions of common genetic variants to risk of schizophrenia among individuals of African and Latino ancestry.

Schizophrenia is a common, chronic and debilitating neuropsychiatric syndrome affecting tens of millions of individuals worldwide. While rare genetic variants play a role in the etiology of schizophrenia, most of the currently explained liability is within common variation, suggesting that variation predating the human diaspora out of Africa harbors a large fraction of the common variant attributable heritability. However, common variant association studies in schizophrenia have concentrated mainly on cohorts of European descent.

Circadian preferences in young adults: Psychometric properties and factor structure of the Portuguese version of the Preferences Scale (PS-6).

Morningness is a trait-like variable which has been extensively studied within chronobiology. Despite the number of existing measures to assess morningness, there is a need for brief instruments that are psychometrically sound to be used in applied settings. Accordingly, the modified version of the Preferences Scale (PS-6) comprises six items and was reported to have adequate reliability and satisfactory validity indicators.

New data and an old puzzle: the negative association between schizophrenia and rheumatoid arthritis.

Background: A long-standing epidemiological puzzle is the reduced rate of rheumatoid arthritis (RA) in those with schizophrenia (SZ) and vice versa. Traditional epidemiological approaches to determine if this negative association is underpinned by genetic factors would test for reduced rates of one disorder in relatives of the other, but sufficiently powered data sets are difficult to achieve. The genomics era presents an alternative paradigm for investigating the genetic relationship between two uncommon disorders.

Association study of 83 candidate genes for bipolar disorder in chromosome 6q selected using an evidence-based prioritization algorithm.

Background: Prior genome-scans of bipolar disorder have revealed chromosome 6q22 as a promising candidate region. However, linkage disequilibrium (LD) mapping studies have yet to identify replicated susceptibility loci.

Methods: We analyzed 1,422 LD-tagging single nucleotide polymorphisms (SNPs) in 83 genes to test single-marker and locus-wide evidence of association with bipolar disorder in the NIMH Genetics Initiative bipolar pedigrees and the Portuguese Island Collection (PIC) (N = 1,093 in 528 informative pairs).

Is positive affect in pregnancy protective of postpartum depression?

Objective: To investigate the predictive/protective role of negative affect/positive affect in late pregnancy on the outcome of postpartum depression.

Methods: A total of 491 pregnant women participated in the study. The participants were asked to fill out a series of questionnaires, which included the Profile of Mood States, the Beck Depression Inventory-II, psychosocial variables and socio-demographic characteristics and were asked to participate in a psychiatric interview.

Short forms of the postpartum depression screening scale: as accurate as the original form.

The aims of the present study were to develop three shorter forms of the Portuguese version of the Postpartum Depression Screening Scale (PDSS) as adapted and translated in Portugal, to analyse their psychometrics and to determine their cut-off points and associated conditional probabilities to screen for perinatal depression according to DSM-IV and ICD-10 criteria. In this study, 441 women in the third trimester of pregnancy and 453 in the third month of postpartum were interviewed for diagnostic purposes according to the Portuguese versions of the Diagnostic Interview for Genetic Studies and the Operational Criteria Checklist for Psychotic Illness. DSM-IV and ICD-10 classifications of depression were our gold standards for caseness.

The role of perfectionism in postpartum depression and symptomatology.

The role of perfectionism as a correlate and as a predictor of perinatal depressive symptomatology and disorder was examined. Three-hundred and eighty-six pregnant women (mean age = 30.08 years; SD = 4.

Epidemiology of perinatal depression in Portugal: categorical and dimensional approach.

The aim of the present study was to estimate depressive disorder and symptomatology prevalence and incidence in perinatal period in a population-based sample. Three-hundred and eighty six Portuguese women (mean age=30.08 years, SD=4.

Revisiting thyroid hormones in schizophrenia.

Thyroid hormones are crucial during development and in the adult brain. Of interest, fluctuations in the levels of thyroid hormones at various times during development and throughout life can impact on psychiatric disease manifestation and response to treatment. Here we review research on thyroid function assessment in schizophrenia, relating interrelations between the pituitary-thyroid axis and major neurosignaling systems involved in schizophrenia's pathophysiology.

Genetic overlap of schizophrenia and bipolar disorder in a high-density linkage survey in the Portuguese Island population.

Recent family and genome-wide association studies strongly suggest shared genetic risk factors for schizophrenia (SZ) and bipolar disorder (BP). However, linkage studies have not been used to test for statistically significant genome-wide overlap between them. Forty-seven Portuguese families with sibpairs concordant for SZ, BP, or psychosis (PSY, which includes either SZ or psychotic BP) were genotyped for over 57,000 markers using the Affymetrix 50K Xba SNP array.

Sleep and academic performance in undergraduates: a multi-measure, multi-predictor approach.

The present study examined the associations of sleep patterns with multiple measures of academic achievement of undergraduate university students and tested whether sleep variables emerged as significant predictors of subsequent academic performance when other potential predictors, such as class attendance, time devoted to study, and substance use are considered. A sample of 1654 (55% female) full-time undergraduates 17 to 25 yrs of age responded to a self-response questionnaire on sleep, academics, lifestyle, and well-being that was administered at the middle of the semester. In addition to self-reported measures of academic performance, a final grade for each student was collected at the end of the semester.

Affective state dependence and relative trait stability of perfectionism in sleep disturbances.

Objective: To evaluate the degree of absolute change, relative stability and state dependence of trait perfectionism in sleep disturbances in a sample of university students.

Method: Participants completed the Multidimensional Perfectionism Scale and two items concerning sleep difficulties. The mean age at T0 (baseline) was 19.

Sleep disturbances, body mass index and eating behaviour in undergraduate students.

This study investigates the association between sleep disturbances, body mass index (BMI) and eating behaviour in a sample of undergraduate students. The sample comprises 870 medicine and dentistry students from Coimbra University (62.5% females), aged between 17 and 25 years.

The postpartum depression screening scale: is it valid to screen for antenatal depression?

The purpose of the study was to analyse for the first time the validity of a slightly modified version of the Portuguese Postpartum Depression Screening Scale (PDSS), to be used as a screening instrument for antenatal depression. Specifically, the aims were to analyse its psychometric properties, to determine PDSS cutoff points and associated conditional probabilities to screen for depression according to DSM-IV and ICD-10 criteria and to compare its screening performance with that of the Beck Depression Inventory-II (BDI-II). Five hundred and three pregnant women in the third trimester of pregnancy completed both questionnaires and were interviewed face-to-face with the Portuguese version of the Diagnostic Interview for Genetic Studies.

Is insomnia in late pregnancy a risk factor for postpartum depression/depressive symptomatology?

The aim of the present work was to investigate if insomnia in late pregnancy is a risk factor for postpartum depressive symptomatology/postpartum depression (PPD). 581 women in their last trimester of pregnancy answered questions/questionnaires about lifetime history of insomnia, current sleep perception, current mood and depressive symptomatology. They were interviewed with the Portuguese version of the Diagnostic Interview for Genetic Studies.

The Portuguese version of the postpartum depression screening scale.

The aim of the present study was to analyse whether the Portuguese version of the Postpartum Depression Screening Scale (PDSS) was a valid instrument for screening postpartum depression. For this purpose the following objectives were delineated: (1) to analyse PDSS psychometric properties; (2) to determine PDSS cut-off points and associated conditional probabilities for screening depression according to DSM-IV and ICD-10 criteria; and (3) to compare the performance of PDSS with the Beck Depression Inventory-II (BDI-II) in screening for postpartum depression. Four hundred eighty-six 3-months-postpartum women completed both questionnaires and were interviewed with the Portuguese version of Diagnostic Interview for Genetic Studies (DIGS).

[The premedical syndrome: does it exist in Portugal?].

Introduction: In Portugal, the medical school selection process relies exclusively on past academic results, involving the most stringent criteria of all courses, with no attention given to the personality traits of the students. In a competitive context, perfectionism dimensions may be relevant to consider. Socially Prescribed Perfectionism (SPP) has been correlated with Neuroticism, while Self-Oriented Perfectionism (SOP) is strongly associated with Conscientiousness.

Longitudinal study on perfectionism and sleep disturbance.

Aim: To examine if perfectionism predicts self-reported sleep disturbances over time.

Methods: The Hewitt-Flett Perfectionism Scale was used to assess self-oriented, socially-prescribed (SPP) and other-oriented perfectionism. Sleep disturbance was evaluated with two items: difficulty in falling asleep and waking up many times during the night.

Perfectionism in obsessive-compulsive and eating disorders.

Objective: The main aims of this article are twofold. First, to assess perfectionism dimensions in obsessive-compulsive disorder and eating disorders in comparison with psychiatric control (depression/anxiety) and non-clinical control groups. Second, to examine if perfectionism is specifically related to these different clinical conditions.

Cell population indexes of spermatogenic yield and testicular sperm reserves in adult jaguars (Panthera onca).

The intrinsic yield of spermatogenesis and supporting capacity of Sertoli cells are the desirable indicators of sperm production in a species. The objective of the present study was to quantify intrinsic yield and the Sertoli cell index in the spermatogenic process and estimate testicular sperm reserves by histological assessment of fragments obtained by testicular biopsy of five adult jaguars in captivity. The testicular fragments were fixed in 4% glutaric aldehyde, dehydrated at increasing alcohol concentrations, included into hydroxyethyl methacrylate, and were cut into 4 microm thickness.

Perfectionism and eating attitudes in Portuguese students: a longitudinal study.

Aim: To investigate the role of perfectionism in the development of disordered eating behaviours.

Method: 382 female university students completed the Hewitt & Flett MPS and the EAT-40 at baseline, and 1 year after (T1) and 206 2 years later (T2).

Results: Perfectionism at baseline was significantly associated with long-term abnormal eating attitudes/behaviours.

Perfectionism dimensions in pregnancy--a study in Portuguese women.

Pregnancy is essentially a physiological event, but neuroendocrinal and psychosocial changes are also important components of this experience. In this context, perceived stress may be enhanced by the activation of certain personality traits, like perfectionism, which in turn may be associated with more psychological distress (PD). The aim of this study was to investigate if perfectionism could be associated with more negative emotional outcomes (PD) in the transition to motherhood and to look at which of the perfectionism dimensions these consequences are specifically linked.