Face recognition in schizophrenia: do individual and average ROCs tell the same story?

Introduction. Many studies have shown that recollection process is impaired in patients with schizophrenia, whereas familiarity is generally spared. However, in these studies, the Receiver Operating Characteristic (ROC) presented is average ROC likely to mask individual differences.

Methods. In the present study using a face-recognition task, we computed the individual ROC of patients with schizophrenia and control participants. Each group was divided into two subgroups on the basis of the type of recognition processes implemented: recognition based on familiarity only and recognition based on familiarity and recollection.

Results. The recognition performance of the schizophrenia patients was below that of the control participants only when recognition was based solely on familiarity. For the familiarity-alone patients, the score obtained on the Scale for the Assessment of Positive Symptoms (SAPS) was correlated with the variance of the old-face familiarity. For the familiarity-recollection patients, the score obtained on the Scale for the Assessment of Negative Symptoms (SANS) was correlated with the decision criterion and with the old-face recollection probability.

Conclusions. These results show that one cannot ascribe the impaired recognition observed in patients with schizophrenia to a recollection deficit alone. These results show that individual ROC can be used to distinguish between subtypes of schizophrenia and could serve as a basis for setting up specific cognitive remediation therapy for individuals with schizophrenia.     

Individual QT–R‐R Relationship: Average Stability over Time Does Not Rule Out an Individual Residual Variability: Implication for the Assessment of Drug Effect on the QT Interval

Background: Universal QT correction formulae have been shown to under or overcorrect the QT interval duration. Individual QT–R‐R modeling has been proposed as a preferable solution for heart rate correction of QT intervals. However, the QT–R‐R relationship stability over time needs to be evaluated. Methods: The present report is part of randomized, double‐dummy, and placebo‐controlled 4‐way crossover phase 1 study (48 healthy volunteers). Each randomized period included a run‐in placebo day followed the day after by drug administration, with moxifloxacin as a positive control for QT interval measurement. Digital Holter ECG data were analyzed using the “bin” approach. For each period, individual QT–R‐R relationship were calculated using two different models (linear and parabolic log–log models). Results: The mean intrasubject variability for the α coefficient of the linear modeling (SDintra = 0.011 ± 0.005) reached 28.6 ± 10.2%. When the parabolic model was considered, the SDintra was 0.026 ± 0.009 for the α coefficient. The QT–R‐R relationship variability was in part related to long‐term RR changes (R²= 30%, P < 0.05). However, no significant time effect (ANOVA) was evidenced for QT–R‐R coefficients. Moxifloxacin significantly increased the α coefficient of the QT–R‐R relationship from 0.07 ± 0.018 to 0.085 ± 0.019, P < 0.05 (linear model). Conclusions: The individual QT–R‐R relationship shows a residual variability in part related to long‐term autonomic changes. In addition, the QT–R‐R relationship might be modulated by the drug tested. As a consequence, pretherapy QT–R‐R relationship obtained in a given patient cannot be used as a fingerprint throughout a drug trial.     

Comparison of non-invasive liver fibrosis biomarkers in HIV/HCV co-infected patients: the fibrovic study--ANRS HC02

BACKGROUND/AIMS: To compare non-invasive biological liver fibrosis scores, as alternatives to liver biopsy, in HIV/HCV co-infected patients. METHODS: Two hundred and seventy-two HIV/HCV patients, nai ve for HCV treatment, underwent liver biopsy [197 (72%) men, 39.9 years, fibrosis stage (Metavir) F1 (25%), F2 (40%), F3 (25%), F4 (10%), median CD4 486/mm(3) and median HIV viral load 3.5log. Fibrotest (FT), Hepascore (HS), Fibrometer (FM), SHASTA, APRI, Forns index, and Fib-4 were tested in order to differentiate patients with mild to moderate fibrosis (F2) and those with advanced fibrosis (F3). The AUROC and the rate of well-classified patients were compared to liver biopsy. RESULTS: FT, HS, and FM were able to stage liver fibrosis in all patients with AUROCs of 0.78, 0.84 and 0.89 for the diagnosis of F2, respectively. The correlation coefficient indexes were 0.37, 0.46 and 0.48, respectively. The rates of well-classified patients were 62%, 68% and 71%, respectively. Fib-4, APRI and the Forn's index were only able to stage 37-61% of patients and showed lower accuracies. Using a combination of FT, HS and FM did not significantly increase the performance of each test. CONCLUSIONS: In HIV/HCV co-infected patients, Fibrometer, Hepascore and Fibrotest outperformed other non-invasive liver fibrosis biomarkers for the prediction of significant liver fibrosis.     

Chromatin-to-nucleoprotamine transition is controlled by the histone H2B variant TH2B

The conversion of male germ cell chromatin to a nucleoprotamine structure is fundamental to the life cycle, yet the underlying molecular details remain obscure. Here we show that an essential step is the genome-wide incorporation of TH2B, a histone H2B variant of hitherto unknown function. Using mouse models in which TH2B is depleted or C-terminally modified, we show that TH2B directs the final transformation of dissociating nucleosomes into protamine-packed structures. Depletion of TH2B induces compensatory mechanisms that permit histone removal by up-regulating H2B and programming nucleosome instability through targeted histone modifications, including lysine crotonylation and arginine methylation. Furthermore, after fertilization, TH2B reassembles onto the male genome during protamine-to-histone exchange. Thus, TH2B is a unique histone variant that plays a key role in the histone-to-protamine packing of the male genome and guides genome-wide chromatin transitions that both precede and follow transmission of the male genome to the egg.     

Postmortem coronary artery calcium score in cases of myocardial infarction

International Journal of Legal Medicine - Sudden cardiac death (SCD) related to atherosclerotic coronary artery disease (ACAD) resulting in myocardial infarction is the most prevalent cause of...     

Household illness is the strongest predictor of upper respiratory tract symptom risk in elite rugby union players

ObjectivesTo identify periods of increased risk for upper respiratory tract symptom (URTS) episodes, and examine whether biomarkers and/or self-reported lifestyle and wellness data can predict URTS risk in elite rugby union players.DesignProspective, longitudinal and repeated-measures study.MethodsSalivary secretory immunoglobulin A (SIgA), salivary cortisol, URTS, internal training load and self-reported lifestyle and wellness data including household illness, stress, mood, fatigue, muscle soreness and sleep quality were repeatedly measured in elite Southern hemisphere rugby union players (n = 28) throughout a season. Univariate frailty model analysis, which included 495 observations, was used to determine predictors of URTS risk.ResultsSurprisingly, the highest incidence of URTS occurred after rest weeks, namely the Christmas break and bye weeks (i.e., no scheduled trainings or matches); whereas URTS risk was reduced during weeks involving international travel (Hazard ratio (HR): 0.43, p < 0.001)). Household illness was the strongest predictor of URTS risk; players were almost three-fold more at risk for an URTS episode when illness in the household was present (HR: 2.90, p = 0.002). A non-significant, but potentially important trend for an inverse association between SIgA concentration and URTS incidence was also observed (HR: 0.99, p = 0.070).ConclusionsRest weeks were identified as periods of increased risk for URTS; while international travel did not appear to increase players risk for URTS. Incidence of household illness and SIgA concentration independently predicted URTS risk, with household illness being the strongest predictor. These findings can assist practitioners monitoring and management of athletes to potentially reduce URTS risk.