High-Mannose Oligosaccharide Hemimimetics that Recapitulate the Conformation and Binding Mode to Concanavalin A, DC-SIGN and Langerin.

The "carbohydrate chemical mimicry" exhibited by sp2 -iminosugars has been utilized to develop practical syntheses for analogs of the branched high-mannose-type oligosaccharides (HMOs) Man3 and Man5 . In these compounds, the terminal nonreducing Man residues have been substituted with 5,6-oxomethylidenemannonojirimycin (OMJ) motifs. The resulting oligomannoside hemimimetic accurately reproduce the structure, configuration, and conformational behavior of the original mannooligosaccharides, as confirmed by NMR and computational techniques. Binding studies with mannose binding lectins, including concanavalin A, DC-SIGN, and langerin, by enzyme-linked lectin assay and surface plasmon resonance revealed significant variations in their ability to accommodate the OMJ unit in the mannose binding site. Intriguingly, OMJMan segments demonstrated "in line" heteromultivalent effects during binding to the three lectins. Similar to the mannobiose (Man2 ) branches in HMOs, the binding modes involving the external or internal monosaccharide unit at the carbohydrate binding-domain exist in equilibrium, facilitating sliding and recapture processes. This equilibrium, which influences the multivalent binding of HMOs, can be finely modulated upon incorporation of the OMJ sp2 -iminosugar caps. As a proof of concept, the affinity and selectivity towards DC-SIGN and langerin were adjustable by presenting the OMJMan epitope in platforms with diverse architectures and valencies.

Long-term diagnostic stability, predictors of diagnostic change, and time until diagnostic change of first-episode psychosis: a 21-year follow-up study.

BACKGROUND: Although diagnostic instability in first-episode psychosis (FEP) is of major concern, little is known about its determinants. This very long-term follow-up study aimed to examine the diagnostic stability of FEP diagnoses, the baseline predictors of diagnostic change and the timing of diagnostic change. METHODS: This was a longitudinal and naturalistic study of 243 subjects with FEP who were assessed at baseline and reassessed after a mean follow-up of 21 years. The diagnostic stability of DSM-5 psychotic disorders was examined using prospective and retrospective consistencies, logistic regression was used to establish the predictors of diagnostic change, and survival analysis was used to compare time to diagnostic change across diagnostic categories. RESULTS: The overall diagnostic stability was 47.7%. Schizophrenia and bipolar disorder were the most stable diagnoses, with other categories having low stability. Predictors of diagnostic change to schizophrenia included a family history of schizophrenia, obstetric complications, developmental delay, poor premorbid functioning in several domains, long duration of untreated continuous psychosis, spontaneous dyskinesia, lack of psychosocial stressors, longer duration of index admission, and poor early treatment response. Most of these variables also predicted diagnostic change to bipolar disorder but in the opposite direction and with lesser effect sizes. There were no significant differences between specific diagnoses regarding time to diagnostic change. At 10-year follow-up, around 80% of the diagnoses had changed. CONCLUSIONS: FEP diagnoses other than schizophrenia or bipolar disorder should be considered as provisional. Considering baseline predictors of diagnostic change may help to enhance diagnostic accuracy and guide therapeutic interventions.

The association of adverse childhood experiences with long-term outcomes of psychosis: a 21-year prospective cohort study after a first episode of psychosis.

BACKGROUND: Evidence suggests a possible relationship between exposure to childhood adversity (CA) and functional impairment in psychosis. However, the impact of CA on long-term outcomes of psychotic disorders remains poorly understood. METHODS: Two hundred and forty-three patients were assessed at their first episode of psychosis for CA and re-assessed after a mean of 21 years of follow-up for several outcome domains, including symptoms, functioning, quality of life, cognitive performance, neurological dysfunction, and comorbidity. The unique predictive ability of CA exposure for outcomes was examined using linear regression analysis controlling for relevant confounders, including socioeconomic status, family risk of schizophrenia, and obstetric complications. RESULTS: There were 54% of the patients with a documented history of CA at mild or higher levels. CA experiences were more prevalent and severe in schizophrenia than in other psychotic disorders (p < 0.001). Large to very large effect sizes were observed for CA predicting most role functioning variables and negative symptoms (ΔR2 between 0.105 and 0.181). Moderate effect sizes were observed for positive symptoms, personal functioning, impaired social cognition, impaired immediate verbal learning, poor global cognition, internalized stigma, poor personal recovery, and drug abuse severity (ΔR2 between 0.040 and 0.066). A dose-response relationship was observed between levels of CA and severity of outcome domains. CONCLUSION: Our results suggest a strong and widespread link between early adversity exposure and outcomes of psychotic disorders. Awareness of the serious long-term consequences of CA should encourage better identification of those at risk and the development of effective interventions.

Additive effects of a family history of schizophrenia spectrum disorders and an environmental risk score for the outcome of patients with non-affective first-episode psychosis.

BACKGROUND: First-episode psychotic disorders comprise a heterogeneous phenotype with a complex etiology involving numerous common small-effect genetic variations and a wide range of environmental exposures. We examined whether a family of schizophrenia spectrum disorder (FH-Sz) interacts with an environmental risk score (ERS-Sz) regarding the outcome of patients with non-affective first episode psychosis (NAFEP). METHODS: We included 288 patients with NAFEP who were evaluated after discharge from an intensive 2-year program. We evaluated three outcome measures: symptomatic remission, psychosocial functioning, and personal recovery. We analyzed the main and joint associations of a FH-Sz and the ERS-Sz on the outcomes by using the relative excess risk due to interaction (RERI) approach. RESULTS: A FH-Sz showed a significant association with poor symptomatic remission and psychosocial functioning outcomes, although there was no significant interaction between a FH-Sz and the ERS-Sz on these outcomes. The ERS-Sz did not show a significant association with poor symptomatic remission and psychosocial functioning outcomes, even though the magnitude of the interaction between ERS-Sz and FH-Sz with the later outcome was moderate (RERI = 6.89, 95% confidence interval -16.03 to 29.81). There was no association between a FH-Sz and the ERS-Sz and personal recovery. CONCLUSIONS: Our results provide further empirical support regarding the contribution of FH-Sz to poor symptomatic remission and poor psychosocial functioning outcomes in patients with NAFEP.

Difficulties during delivery, brain ventricle enlargement and cognitive impairment in first episode psychosis.

BACKGROUND: Patients with a first episode of psychosis (FEP) display clinical, cognitive, and structural brain abnormalities at illness onset. Ventricular enlargement has been identified in schizophrenia since the initial development of neuroimaging techniques. Obstetric abnormalities have been associated with an increased risk of developing psychosis but also with cognitive impairment and brain structure abnormalities. Difficulties during delivery are associated with a higher risk of birth asphyxia leading to brain structural abnormalities, such as ventriculomegaly, which has been related to cognitive disturbances. METHODS: We examined differences in ventricular size between 142 FEP patients and 123 healthy control participants using magnetic resonance imaging. Obstetric complications were evaluated using the Lewis-Murray scale. We examined the impact of obstetric difficulties during delivery on ventricle size as well as the possible relationship between ventricle size and cognitive impairment in both groups. RESULTS: FEP patients displayed significantly larger third ventricle size compared with healthy controls. Third ventricle enlargement was associated with diagnosis (higher volume in patients), with difficulties during delivery (higher volume in subjects with difficulties), and was highest in patients with difficulties during delivery. Verbal memory was significantly associated with third ventricle to brain ratio. CONCLUSIONS: Our results suggest that difficulties during delivery might be significant contributors to the ventricular enlargement historically described in schizophrenia. Thus, obstetric complications may contribute to the development of psychosis through changes in brain architecture.

Social exclusion as a major outcome domain of psychotic disorders: early predictors, and associations with non-recovery and clinical staging 21 years after a first episode of psychosis.

PURPOSE: People with psychotic disorders have high levels of social exclusion; however, little is known about its early predictors. We present a long-term observational cohort study aimed at examining early risk factors for later social exclusion. METHODS: A total of 243 subjects were assessed at their first psychotic episode for early risk factors including sociodemographic variables, familial risk of major mental disorders, perinatal complications, childhood factors, and adolescent factors and re-assessed after a mean follow-up of 21 years for 12 social exclusion domains: leisure activities, housing, work, income, neighborhood deprivation, educational attainment, physical and mental health, family and social support, legal competence, and discrimination. The ability of risk factors to predict social exclusion was examined using hierarchical linear regression. RESULTS: Overall social exclusion was independently predicted by low parental socio-economic status, length of follow-up, familial risk of schizophrenia, obstetric complications, neurodevelopmental delay, poor childhood adjustment, childhood adversity, poor adolescent social networks, poor adolescent adjustment, and low premorbid IQ. The model explained 58.2% of the variance in total social exclusion score. Each social exclusion domain was predicted by a different set of variables, which explained between 17.8 and 57.0% of their variance, although low socio-economic status, familial risk of schizophrenia, obstetric complications, childhood adversity, and poor social networks predicted most of the social exclusion domains. CONCLUSION: Early risk factors strongly predicted later social exclusion. A multifaceted approach to preventing later social exclusion is crucial in people with a first episode of psychosis and early risk factors of social exclusion.

Neurocognitive and social cognitive correlates of social exclusion in psychotic disorders: a 20-year follow-up cohort study.

PURPOSE: Little is known about the relationship between social exclusion and cognitive impairment in psychosis. We conducted a long-term cohort study of first-episode psychosis to examine the association between comprehensive measures of cognitive impairment and social exclusion assessed at follow-up. METHODS: A total of 173 subjects with first-episode psychosis were assessed after a 20-year follow-up for 7 cognitive domains and 12 social exclusion indicators. Associations between sets of variables were modeled using multivariate regression, where social exclusion indicators were the dependent variables, cognitive domains were the independent variables, and age, gender, and duration of follow-up were covariates. RESULTS: The total scores on the measures of cognition and social exclusion were strongly associated (ß = - .469, ∆R2 = 0.215). Participants with high social exclusion were 4.24 times more likely to have cognitive impairment than those with low social exclusion. Verbal learning was the cognitive function most related to social exclusion domains, and legal capacity was the exclusion domain that showed the strongest relationships with individual cognitive tests. Neurocognition uniquely contributed to housing, work activity, income, and educational attainment, whereas social cognition uniquely contributed to neighborhood deprivation, family and social contacts, and discrimination/stigma. Neurocognition explained more unique variance (11.5%) in social exclusion than social cognition (5.5%). CONCLUSION: The domains of cognitive impairment were strongly and differentially related to those of social exclusion. Given that such an association pattern is likely bidirectional, a combined approach, both social and cognitive, is of paramount relevance in addressing the social exclusion experienced by individuals with psychotic disorders.

Prodromal symptoms and the duration of untreated psychosis in first episode of psychosis patients: what differences are there between early vs. adult onset and between schizophrenia vs. bipolar disorder?

To assess the role of age (early onset psychosis-EOP < 18 years vs. adult onset psychosis-AOP) and diagnosis (schizophrenia spectrum disorders-SSD vs. bipolar disorders-BD) on the duration of untreated psychosis (DUP) and prodromal symptoms in a sample of patients with a first episode of psychosis. 331 patients with a first episode of psychosis (7-35 years old) were recruited and 174 (52.6%) diagnosed with SSD or BD at one-year follow-up through a multicenter longitudinal study. The Symptom Onset in Schizophrenia (SOS) inventory, the Positive and Negative Syndrome Scale and the structured clinical interviews for DSM-IV diagnoses were administered. Generalized linear models compared the main effects and group interaction. 273 AOP (25.2 ± 5.1 years; 66.5% male) and 58 EOP patients (15.5 ± 1.8 years; 70.7% male) were included. EOP patients had significantly more prodromal symptoms with a higher frequency of trouble with thinking, avolition and hallucinations than AOP patients, and significantly different median DUP (91 [33-177] vs. 58 [21-140] days; Z = - 2.006, p = 0.045). This was also significantly longer in SSD vs. BD patients (90 [31-155] vs. 30 [7-66] days; Z = - 2.916, p = 0.004) who, moreover had different profiles of prodromal symptoms. When assessing the interaction between age at onset (EOP/AOP) and type of diagnosis (SSD/BD), avolition was significantly higher (Wald statistic = 3.945; p = 0.047), in AOP patients with SSD compared to AOP BD patients (p = 0.004). Awareness of differences in length of DUP and prodromal symptoms in EOP vs. AOP and SSD vs. BD patients could help improve the early detection of psychosis among minors.

Potent and Selective Cell-Active Iminosugar Inhibitors of Human α-N-Acetylgalactosaminidase (α-NAGAL).

Glycoside hydrolases (GHs) are a class of enzymes with emerging roles in a range of disease. Selective GH inhibitors are sought to better understand their functions and assess the therapeutic potential of modulating their activities. Iminosugars are a promising class of GH inhibitors but typically lack the selectivity required to accurately perturb biological systems. Here, we describe a concise synthesis of iminosugar inhibitors of N-acetyl-α-galactosaminidase (α-NAGAL), the GH responsible for cleaving terminal α-N-acetylgalactosamine residues from glycoproteins and other glycoconjugates. Starting from non-carbohydrate precursors, this modular synthesis supported the identification of a potent (490 nM) and α-NAGAL selective (∼200-fold) guanidino-containing derivative DGJNGuan. To illustrate the cellular activity of this new inhibitor, we developed a quantitative fluorescence image-based method to measure levels of the Tn-antigen, a cellular glycoprotein substrate of α-NAGAL. Using this assay, we show that DGJNGuan exhibits excellent inhibition of α-NAGAL within cells using patient derived fibroblasts (EC50 =150 nM). Moreover, in vitro and in cell assays to assess levels of lysosomal ß-hexosaminidase substrate ganglioside GM2 show that DGJNGuan is selective whereas DGJNAc exhibits off-target inhibition both in vitro and within cells. DGJNGuan is a readily produced and selective tool compound that should prove useful for investigating the physiological roles of α-NAGAL.

Schneider's first-rank symptoms have neither diagnostic value for schizophrenia nor higher clinical validity than other delusions and hallucinations in psychotic disorders.

The validity of studies on the diagnostic significance of first-rank symptoms (FRS) for schizophrenia has been put in doubt because of a poor compliance with Schneider's criterion for their definition and the lack of use of the phenomenological method for their assessment. In this study, using a rigorously phenomenological approach to elicit FRS, we examined (a) the degree to which unequivocally present FRS differentiated schizophrenia (n=513) from other psychotic disorders (n=633), and (b) the comparative validity between FRS and other reality-distortion symptoms against 16 external validators in the whole sample of psychotic disorders (n=1146). Diagnostic performance indices (with 95% CIs) of FRS for diagnosing schizophrenia were as follows: sensitivity=0.58 (0.54-0.61), specificity=0.65 (0.62-0.67), positive predictive value=0.57 (0.54-0.60) and negative predictive value=0.65 (0.63-0.68). While the overall association pattern of FRS and non-FRS scores with the validators was rather similar, three validators (premorbid social adjustment, number of hospitalizations and global assessment of functioning) were significantly related to non-FRS scores (p < 0.006) but not to FRS scores (p > 0.05). Furthermore, no validator was significantly related to FRS scores and unrelated to non-FRS scores, all of which indicates an overall better predictive validity for non-FRS delusions and hallucinations. These findings suggest that FRS do not have diagnostic value for diagnosing schizophrenia and that they do not meaningfully add to the external validity showed by other delusions and hallucinations. We believe that much of the misunderstanding about the diagnostic and clinical validity of FRS for schizophrenia is rooted in Schneider's confusing concept of the disorder.

Link between cognitive polygenic risk scores and clinical progression after a first-psychotic episode.

BACKGROUND: Clinical intervention in early stages of psychotic disorders is crucial for the prevention of severe symptomatology trajectories and poor outcomes. Genetic variability is studied as a promising modulator of prognosis, thus novel approaches considering the polygenic nature of these complex phenotypes are required to unravel the mechanisms underlying the early progression of the disorder. METHODS: The sample comprised of 233 first-episode psychosis (FEP) subjects with clinical and cognitive data assessed periodically for a 2-year period and 150 matched controls. Polygenic risk scores (PRSs) for schizophrenia, bipolar disorder, depression, education attainment and cognitive performance were used to assess the genetic risk of FEP and to characterize their association with premorbid, baseline and progression of clinical and cognitive status. RESULTS: Schizophrenia, bipolar disorder and cognitive performance PRSs were associated with an increased risk of FEP [false discovery rate (FDR) ⩽ 0.027]. In FEP patients, increased cognitive PRSs were found for FEP patients with more cognitive reserve (FDR ⩽ 0.037). PRSs reflecting a genetic liability for improved cognition were associated with a better course of symptoms, functionality and working memory (FDR ⩽ 0.039). Moreover, the PRS of depression was associated with a worse trajectory of the executive function and the general cognitive status (FDR ⩽ 0.001). CONCLUSIONS: Our study provides novel evidence of the polygenic bases of psychosis and its clinical manifestation in its first stage. The consistent effect of cognitive PRSs on the early clinical progression suggests that the mechanisms underlying the psychotic episode and its severity could be partially independent.

Obstetric complications and genetic risk for schizophrenia: Differential role of antenatal and perinatal events in first episode psychosis.

BACKGROUND: Obstetric complications (OCs) are key contributors to psychosis risk. However, it is unclear whether they increase psychosis vulnerability independently of genetic risk, in interaction with it, or are a manifestation of psychosis proneness. We examined the role of distinct types of OCs in terms of psychosis risk and tested whether they interact differently with genetic vulnerability, whilst accounting for other known environmental risk factors. STUDY DESIGN: 405 participants (219 first episode psychosis patients and 186 healthy volunteers) underwent a comprehensive assessment of OCs, measured using the Lewis-Murray scale and divided into complications of pregnancy, abnormalities of foetal growth and development, and complications of delivery. Participants were compared in terms of history of OCs, polygenic risk score for schizophrenia (PRS-SZ) and interactions between these. RESULTS: Both complications of pregnancy and abnormalities of foetal growth were significantly associated with case-control status (p = 0.02 and 0.03, respectively), whereas complications of delivery were not. PRS-SZ showed a significant association with psychosis (p = 0.04), but there were no significant interactions between genetic risk for schizophrenia and OCs, either when these were considered globally or separated based on their timeframe. CONCLUSIONS: We observed no significant interaction between genetic and obstetric vulnerability, yet distinct types of OCs may have a different impact on psychosis risk, based on their nature and timeframe. Examining their differential role might clarify their relative contributions to this risk.

Small area variations in non-affective first-episode psychosis: the role of socioeconomic and environmental factors.

BACKGROUND: There is strong evidence supporting the association between environmental factors and increased risk of non-affective psychotic disorders. However, the use of sound statistical methods to account for spatial variations associated with environmental risk factors, such as urbanicity, migration, or deprivation, is scarce in the literature. METHODS: We studied the geographical distribution of non-affective first-episode psychosis (NA-FEP) in a northern region of Spain (Navarra) during a 54-month period considering area-level socioeconomic indicators as putative explanatory variables. We used several Bayesian hierarchical Poisson models to smooth the standardized incidence ratios (SIR). We included neighborhood-level variables in the spatial models as covariates. RESULTS: We identified 430 NA-FEP cases over a 54-month period for a population at risk of 365,213 inhabitants per year. NA-FEP incidence risks showed spatial patterning and a significant ecological association with the migrant population, unemployment, and consumption of anxiolytics and antidepressants. The high-risk areas corresponded mostly to peripheral urban regions; very few basic health sectors of rural areas emerged as high-risk areas in the spatial models with covariates. DISCUSSION: Increased rates of unemployment, the migrant population, and consumption of anxiolytics and antidepressants showed significant associations linked to the spatial-geographic incidence of NA-FEP. These results may allow targeting geographical areas to provide preventive interventions that potentially address modifiable environmental risk factors for NA-FEP. Further investigation is needed to understand the mechanisms underlying the associations between environmental risk factors and the incidence of NA-FEP.

Obstetric complications and clinical presentation in first episode of psychosis.

OBJECTIVE: Psychotic disorders exhibit a complex aetiology that combines genetic and environmental factors. Among the latter, obstetric complications (OCs) have been widely studied as risk factors, but it is not yet well understood how OCs relate to the heterogeneous presentations of psychotic disorders. We assessed the clinical phenotypes of individuals with a first episode of psychosis (FEP) in relation to the presence of OCs. METHODS: Two-hundred seventy-seven patients with an FEP were assessed for OCs using the Lewis-Murray scale, with data stratified into three subscales depending on the timing and the characteristics of the obstetric event, namely: complications of pregnancy, abnormal foetal growth and development and difficulties in delivery. We also considered other two groups: any complications during the pregnancy period and all OCs taken altogether. Patients were clinically evaluated with the Positive and Negative Syndrome Scale for schizophrenia. RESULTS: Total OCs and difficulties in delivery were related to more severe psychopathology, and this remained significant after co-varying for age, sex, traumatic experiences, antipsychotic dosage and cannabis use. CONCLUSIONS: Our results highlight the relevance of OCs for the clinical presentation of psychosis. Describing the timing of the OCs is essential in understanding the heterogeneity of the clinical presentation.

Bicyclic Picomolar OGA Inhibitors Enable Chemoproteomic Mapping of Its Endogenous Post-translational Modifications.

Owing to its roles in human health and disease, the modification of nuclear, cytoplasmic, and mitochondrial proteins with O-linked N-acetylglucosamine residues (O-GlcNAc) has emerged as a topic of great interest. Despite the presence of O-GlcNAc on hundreds of proteins within cells, only two enzymes regulate this modification. One of these enzymes is O-GlcNAcase (OGA), a dimeric glycoside hydrolase that has a deep active site cleft in which diverse substrates are accommodated. Chemical tools to control OGA are emerging as essential resources for helping to decode the biochemical and cellular functions of the O-GlcNAc pathway. Here we describe rationally designed bicyclic thiazolidine inhibitors that exhibit superb selectivity and picomolar inhibition of human OGA. Structures of these inhibitors in complex with human OGA reveal the basis for their exceptional potency and show that they extend out of the enzyme active site cleft. Leveraging this structure, we create a high affinity chemoproteomic probe that enables simple one-step purification of endogenous OGA from brain and targeted proteomic mapping of its post-translational modifications. These data uncover a range of new modifications, including some that are less-known, such as O-ubiquitination and N-formylation. We expect that these inhibitors and chemoproteomics probes will prove useful as fundamental tools to decipher the mechanisms by which OGA is regulated and directed to its diverse cellular substrates. Moreover, the inhibitors and structures described here lay out a blueprint that will enable the creation of chemical probes and tools to interrogate OGA and other carbohydrate active enzymes.

The impact of cognitive reserve, cognition and clinical symptoms on psychosocial functioning in first-episode psychoses.

BACKGROUND: Functional impairment is a defining feature of psychotic disorders. A range of factors has been shown to influence functioning, including negative symptoms, cognitive performance and cognitive reserve (CR). However, it is not clear how these variables may affect functioning in first-episode psychosis (FEP) patients. This 2-year follow-up study aimed to explore the possible mediating effects of CR on the relationship between cognitive performance or specific clinical symptoms and functional outcome. METHODS: A prospective study of non-affective FEP patients was performed (211 at baseline and 139 at follow-up). CR was entered in a path analysis model as potential mediators between cognitive domains or clinical symptoms and functioning. RESULTS: At baseline, the relationship between clinical variables or cognitive performance and functioning was not mediated by CR. At follow-up, the effect of attention (p = 0.003) and negative symptoms (p = 0.012) assessed at baseline on functioning was partially mediated by CR (p = 0.032 and 0.016), whereas the relationship between verbal memory (p = 0.057) and functioning was mediated by CR (p = 0.014). Verbal memory and positive and total subscales of PANSS assessed at follow-up were partially mediated by CR and the effect of working memory on functioning was totally mediated by CR. CONCLUSIONS: Our results showed the influence of CR in mediating the relationship between cognitive domains or clinical symptoms and functioning in FEP. In particular, CR partially mediated the relationship between some cognitive domains or clinical symptoms and functioning at follow-up. Therefore, CR could improve our understanding of the long-term functioning of patients with a non-affective FEP.

Assessment of cognitive impairment in psychosis spectrum disorders through self-reported and interview-based measures.

Self-reported and interview-based measures can be considered coprimary measures of cognitive performance. We aimed to ascertain to what extent cognitive impairment in psychotic disorders, as assessed with a neuropsychological battery, is associated with subjective cognitive complaints compared to difficulties in daily activities caused by cognitive impairment. We assessed 114 patients who had a psychotic disorder with a set of neuropsychological tests and two additional measures: the Cognitive Assessment Interview-Spanish version (CAI-Sp) and the Frankfurt Complaint Questionnaire (FCQ). Patients also underwent a clinical assessment. The CAI-Sp correlated significantly with all the clinical dimensions, while the FCQ correlated only with positive and depressive symptoms. The CAI-Sp correlated significantly with all cognitive domains, except for verbal memory and social cognition. The FCQ was associated with attention, processing speed and working memory. The combination of manic and depressive symptoms and attention, processing speed, working memory and explained 38-46% of the variance in the patients' CAI-Sp. Education and negative symptoms, in combination with attention, processing speed, and executive functions, explained 54-59% of the CAI-Sp rater's variance. Only negative symptoms explained the variance in the CAI-Sp informant scores (37-42%). Depressive symptoms with attention and working memory explained 15% of the FCQ variance. The ability to detect cognitive impairment with the CAI-Sp and the FCQ opens the possibility to consider these instruments to approximate cognitive impairment in clinical settings due to their ease of application and because they are less time-consuming for clinicians.

A neuropsychological study on Leonhard's nosological system.

Phenotype validation of endogenous psychosis is a problem that remains to be solved. This study investigated the neuropsychological performance of endogenous psychosis subtypes according to Wernicke-Kleist-Leonhard's classification system (WKL). The participants included consecutive admissions of patients with schizophrenia spectrum disorder or mood disorder with psychotic symptoms (N = 98) and healthy comparison subjects (N = 50). The patients were assessed by means of semi-structured interviews and diagnosed through the WKL system into three groups: a manic-depressive illness and cycloid psychosis group (MDC), unsystematic schizophrenia (USch) and systematic schizophrenia (SSch). All the participants completed a comprehensive neuropsychological battery. The three Leonhard's psychosis subtypes showed a common neuropsychological profile with differences in the severity of impairment relative to healthy controls. MDC patients showed better performance on premorbid intelligence, verbal memory and global cognitive index than USch and SSch patients, and they showed better performance on processing speed, and working memory than SSch patients. USch patients outperformed SSch patients in verbal memory, working memory and global cognitive index. Neuropsychological performance showed a modest accuracy for classification into the WKL nosology. Our results suggest the existence of a common profile of cognitive impairment cutting across WKL subtypes of endogenous psychosis but with significant differences on a severity continuum. In addition, classification accuracy in the three WKL subtypes by means of neuropsychological performance was modest, ranging between 40 and 64% of correctly classified patients.

sp2-Iminosugars targeting human lysosomal ß-hexosaminidase as pharmacological chaperone candidates for late-onset Tay-Sachs disease.

The late-onset form of Tay-Sachs disease displays when the activity levels of human ß-hexosaminidase A (HexA) fall below 10% of normal, due to mutations that destabilise the native folded form of the enzyme and impair its trafficking to the lysosome. Competitive inhibitors of HexA can rescue disease-causative mutant HexA, bearing potential as pharmacological chaperones, but often also inhibit the enzyme O-glucosaminidase (GlcNAcase; OGA), a serious drawback for translation into the clinic. We have designed sp2-iminosugar glycomimetics related to GalNAc that feature a neutral piperidine-derived thiourea or a basic piperidine-thiazolidine bicyclic core and behave as selective nanomolar competitive inhibitors of human Hex A at pH 7 with a ten-fold lower inhibitory potency at pH 5, a good indication for pharmacological chaperoning. They increased the levels of lysosomal HexA activity in Tay-Sachs patient fibroblasts having the G269S mutation, the highest prevalent in late-onset Tay-Sachs disease.

Dependence Graphs Based on Association Rules to Explore Delusional Experiences.

Methods to estimate dependence graphs among variables, have quickly gained popularity in psychopathology research. To date, multiple methods have been proposed but recent studies report several drawbacks impacting on the validity of the conclusions as it is argued that assumptions and conditions underlying the methods commonly used and the nature of the data is lacking alignment. A particularly important issue is that underlying dynamics potentially present in heterogeneous datasets are disregarded, as the methods focus on the variables but not on individuals. This work also argues that the networks may lack relevant components as current methods ignore connections beyond pairwise interactions between individual symptoms. This study addresses these issues with a novel method for constructing dependence graphs based on applying Association Rules to binary records, which is often the type of records in the psychopathology domain. To demonstrate the benefits, we examine 12 delusional experiences in a sample of 1423 subjects with psychotic disorders. We show that by extracting Association Rules using an algorithm called apriori, in addition to facilitating an intuitive interpretation, previously unseen relevant dependencies are revealed from higher order interactions among psychotic experiences in subgroups of patients.