Child Sexual Abuse and Age at Onset of Psychotic Disorders: A Matched-cohort Study: L'âge d'apparition des troubles psychotiques chez les victimes d'agression sexuelle à l'enfance: Une étude prospective de cohortes appariées.

OBJECTIVE: Victims of child sexual abuse (CSA) present with a higher risk of psychotic disorders. However, the developmental course of psychosis following CSA, such as the age at onset, remains unknown. This study aimed to determine whether the age at onset of psychotic disorders was influenced by sexual abuse, sex, and confounding factors (substance misuse, intellectual disability, and socioeconomic status). METHOD: A prospective matched-cohort design was used, with administrative databases from a child protection agency (CPA) and a public health system. Children who received a substantiated report of CSA at the CPA and whose health data could be retrieved were selected (n = 882) and matched with children from the general population using their date of birth, sex, and geographical area. Survival analysis was performed to estimate the association between sexual abuse, sex, and confounding factors and the age at onset of psychotic disorders. RESULTS: Sexual abuse and substance misuse are significantly associated with the age at onset of psychotic disorders. In the sexually abused group, only substance misuse is associated with the age at onset of psychotic disorders, but this was not significant for the general population. CONCLUSIONS: These findings highlight the importance of prevention of psychotic disorders among sexually abused youth, especially those with a substance misuse diagnosis.

Interaction of endogenous tau protein with synaptic proteins is regulated by N-methyl-D-aspartate receptor-dependent tau phosphorylation.

Amyloid-ß and tau protein are the two most prominent factors in the pathology of Alzheimer disease. Recent studies indicate that phosphorylated tau might affect synaptic function. We now show that endogenous tau is found at postsynaptic sites where it interacts with the PSD95-NMDA receptor complex. NMDA receptor activation leads to a selective phosphorylation of specific sites in tau, regulating the interaction of tau with Fyn and the PSD95-NMDA receptor complex. Based on our results, we propose that the physiologically occurring phosphorylation of tau could serve as a regulatory mechanism to prevent NMDA receptor overexcitation.

Elemental 2D imaging of paintings with a mobile EDXRF system.

Imaging techniques are now used commonly and intensively in cultural heritage object analysis. Nowadays, many different techniques in nature as well as many applications exist, where they can be applied. X-ray radiography and infrared reflectography as well as UV photography are some of the most applied techniques. The study of works of art usually requires these techniques to be non-invasive. Furthermore, they are frequently required to perform in situ analysis. A few years ago, our laboratory developed a mobile energy-dispersive X-ray fluorescence and UV-vis-NIR coupled spectrometer, especially designed for fieldwork studies, where all three techniques can be applied strictly at the same site of analysis. Recent developments on a new positioning system have now allowed us to perform 2D elemental mappings with our equipment, which is especially well adapted to painting analysis. The system control is carried out entirely through a laptop computer running a dedicated homemade software. The positioning is achieved by means of a CCD camera embedded in the system and controlled via a Wi-Fi connection through the computer. The data acquisition system, which is made through a homemade multichannel pulse height analyzer, being also managed via the software mentioned above, goes through an Ethernet connection. We will present here the new developments of the system and an example of in situ 2D elemental mapping applied on an anonymous oil painting on wood panel. The discovery of a hidden painting under this oil painting makes it a good choice for a first example of 2D large scan with a mobile instrument.

Mental health disorders as cooccuring and predictive factors of psychotic disorders in sexually abused children.

BACKGROUND: Little is known about the factors associated with psychosis in sexually abused children. Many factors have been associated with both sexual abuse and psychosis, and some mental health disorders have been identified as implied in the relationship between childhood trauma and psychosis. OBJECTIVES: This study aims to identify factors cooccurring with psychotic disorders in sexually abused youth and to determine which predict the development of psychosis in this population. PARTICIPANTS AND SETTING: Children with a corroborated report of sexual abuse (n = 882) at a Child Protection Agency (CPA) between 2000 and 2010 and whose health data could be retrieved from public health databases were selected for this study. METHODS: A prospective matched-cohort design was used, with administrative databases from a CPA and a public health system. Logistic regressions were performed to determine which mental health diagnoses were associated with, and which predicted, psychotic disorders. RESULTS: Logistic regressions revealed that personality disorders were significantly associated with psychotic disorders whereas substance misuse disorders and intellectual disability significantly predicted psychotic disorders. CONCLUSIONS: Psychotic disorders and personality disorders appear concomitantly in sexually abused youth. Having received a substance misuse disorder diagnosis increases the risk of developing a psychotic disorder in sexually abused youth. Health professionals should be aware of those risk factors to help reduce the severity of youth sexual abuse consequences and, ultimately, prevent psychosis.

Persistent transcription- and translation-dependent long-term potentiation induced by mGluR1 in hippocampal interneurons.

Hippocampal interneurons synchronize the activity of large neuronal ensembles during memory consolidation. Although the latter process is manifested as increases in synaptic efficacy which require new protein synthesis in pyramidal neurons, it is unknown whether such enduring plasticity occurs in interneurons. Here, we uncover a long-term potentiation (LTP) of transmission at individual interneuron excitatory synapses which persists for at least 24 h, after repetitive activation of type-1 metabotropic glutamate receptors [mGluR1-mediated chemical late LTP (cL-LTP(mGluR1))]. cL-LTP(mGluR1) involves presynaptic and postsynaptic expression mechanisms and requires both transcription and translation via phosphoinositide 3-kinase/mammalian target of rapamycin and MAP kinase kinase-extracellular signal-regulated protein kinase signaling pathways. Moreover, cL-LTP(mGluR1) involves translational control at the level of initiation as it is prevented by hippuristanol, an inhibitor of eIF4A, and facilitated in mice lacking the cap-dependent translational repressor, 4E-BP. Our results reveal novel mechanisms of long-term synaptic plasticity that are transcription and translation-dependent in inhibitory interneurons, indicating that persistent synaptic modifications in interneuron circuits may contribute to hippocampal-dependent cognitive processes.

Psychotic disorders in sexually abused youth: A prospective matched-cohort study.

Child sexual abuse has been identified as a potential risk factor for developing a psychotic disorder. However, little is known about the prevalence of psychotic disorders in youth who were sexually abused during adolescence and young adulthood. Gender differences also remain unclear. This study used administrative databases from a Child Protection Agency and a public health care system. It aimed to investigate the prevalence of psychotic disorders in sexually abused youth between the first substantiated report of sexual abuse and the beginning of adulthood. A second objective was to assess gender differences. Administrative health data for 882 sexually abused youth were compared with 882 matched controls from the general population over a 13-year period using conditional generalized linear mixed models. Stratified analyses by gender (group comparison) and group (gender comparison) were also performed. Sexually abused youth were 10 times more at risk of receiving a diagnosis of psychotic disorder than youth from the general population. There was no gender difference in the prevalence of psychotic disorders among sexually abused youth. These results highlight the importance of targeted prevention of psychotic disorders among sexually abused youth. Future studies should investigate risk factors and developmental trajectories of psychotic disorders in this population.

Physical and mental health of children with substantiated sexual abuse: Gender comparisons from a matched-control cohort study.

When compared to children from the general population, sexually abused children receive more medical services, both for physical and mental health problems. However, possible differences between sexually abused boys and girls remain unknown. The lack of control group in studies that find gender differences also prevents from determining if the differences are specific to sexual abuse or to gender. The objective of the study was to assess differences in physical and mental health between sexually abused boys and girls in comparison to those from the general population. Administrative databases were used to document physical and mental health problems of 222 males and 660 females with a substantiated report of sexual abuse between 2001 and 2010. A comparison group individually matched to those from the sexually abused group on gender, age and geographic area was also used to document gender differences in the general population. Yearly incidence rates of diagnoses resulting from medical consultations and hospitalizations of males and females were compared over five years after a first substantiated sexual abuse report using the mixed general linear model. Sexually abused girls were up to 2.2 times more likely to consult a physician than sexually abused boys for physical health problems. Similar findings are observed in the general population. Conversely, results revealed that sexually abused boys were up to 2.3 times more likely than females to consult a physician for mental health problems. This gender difference was not apparent in the general population group.

NMDA-receptor activation but not ion flux is required for amyloid-beta induced synaptic depression.

Alzheimer disease is characterized by a gradual decrease of synaptic function and, ultimately, by neuronal loss. There is considerable evidence supporting the involvement of oligomeric amyloid-beta (Aß) in the etiology of Alzheimer's disease. Historically, AD research has mainly focused on the long-term changes caused by Aß rather than analyzing its immediate effects. Here we show that acute perfusion of hippocampal slice cultures with oligomeric Aß depresses synaptic transmission within 20 minutes. This depression is dependent on synaptic stimulation and the activation of NMDA-receptors, but not on NMDA-receptor mediated ion flux. It, therefore, appears that Aß dependent synaptic depression is mediated through a use-dependent metabotropic-like mechanism of the NMDA-receptor, but does not involve NMDA-receptor mediated synaptic transmission, i.e. it is independent of calcium flux through the NMDA-receptor.