RESUMEN
Machine learning has increasingly been applied to classification of schizophrenia in neuroimaging research. However, direct replication studies and studies seeking to investigate generalizability are scarce. To address these issues, we assessed within-site and between-site generalizability of a machine learning classification framework which achieved excellent performance in a previous study using two independent resting-state functional magnetic resonance imaging data sets collected from different sites and scanners. We established within-site generalizability of the classification framework in the main data set using cross-validation. Then, we trained a model in the main data set and investigated between-site generalization in the validated data set using external validation. Finally, recognizing the poor between-site generalization performance, we updated the unsupervised algorithm to investigate if transfer learning using additional unlabeled data were able to improve between-site classification performance. Cross-validation showed that the published classification procedure achieved an accuracy of 0.73 using majority voting across all selected components. External validation found a classification accuracy of 0.55 (not significant) and 0.70 (significant) using the direct and transfer learning procedures, respectively. The failure of direct generalization from one site to another demonstrates the limitation of within-site cross-validation and points toward the need to incorporate efforts to facilitate application of machine learning across multiple data sets. The improvement in performance with transfer learning highlights the importance of taking into account the properties of data when constructing predictive models across samples and sites. Our findings suggest that machine learning classification result based on a single study should be interpreted cautiously.
Asunto(s)
Conectoma/métodos , Imagen por Resonancia Magnética/métodos , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/fisiopatología , Aprendizaje Automático no Supervisado , Adulto , Conectoma/normas , Femenino , Humanos , Imagen por Resonancia Magnética/normas , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Aprendizaje Automático no Supervisado/normasRESUMEN
BACKGROUND: The neuropsychological origins of negative syndrome of schizophrenia remain elusive. Evidence from behavioural studies, which utilised emotion-inducing pictures to elicit motivated behaviour generally reported that that schizophrenia patients experienced similar affective experience as healthy individuals but failed to translate emotional salience to motivated behaviour, a phenomenon called emotion-behaviour decoupling. However, a few studies have examined emotion-behaviour decoupling in non-psychotic high-risk populations, who are relatively unaffected by medication effects. METHODS: In this study, we examined the nature and extent of emotion-behaviour decoupling in in three independent samples (65 schizophrenia patients v. 63 controls; 40 unaffected relatives v. 45 controls; and 32 individuals with social anhedonia v. 32 controls). We administered an experimental task to examine their affective experience and its coupling with behaviour, using emotion-inducing slides, and allowed participants to alter stimulus exposure using button-pressing to seek pleasure or avoid aversion. RESULTS: Schizophrenia patients reported similar affective experiences as their controls, while their unaffected relatives and individuals with high levels of social anhedonia exhibited attenuated affective experiences, in particular in the arousal aspect. Compared with their respective control groups, all of the three groups showed emotion-behaviour decoupling. CONCLUSIONS: Our findings support that both genetically and behaviourally high-risk groups exhibit emotion-behaviour decoupling. The familial association apparently supports its role as a putative trait marker for schizophrenia.
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Anhedonia , Emociones , Motivación , Esquizofrenia/fisiopatología , Trastorno de la Personalidad Esquizotípica/fisiopatología , Adulto , Beijing , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placer , AutoinformeRESUMEN
To explore the effect of leech on proliferation and apoptosis of vascular smooth muscle cells(VSMCs) in early atherosclerosis rats via p38MAPK signaling pathway and investigate its possible mechanism. Biochemical analyzer was used to examine the regulation of leech on levels of triglycerides(TG), total cholesterol(TC), low-density lipoprotein(LDL-C), and high-density lipoprotein(HDL-C) in blood lipid of rats. The expression of transforming growth factor-beta 1(TGF-ß1) in serum was detected by ELISA. Immunological histological chemistry (IHC) was taken to measure the expression levels of proliferating cell nucleus antigen(PCNA) and cell apoptosis proteinase-3(Caspase-3), while the protein expression levels of MKK3, p38 and C-myc were detected by Western blot. In addition, hematoxylin and eosin(HE) staining was used to observe the morphological change of thoracic aortas. The results showed that leech decreased the levels of TC, LDL-C obviously and increased HDL-C, suppressed the expression levels of TGF-ß1 and PCNA, up-regulated Caspase-3, down-regulated the expression levels of MKK3, p38, and C-myc protein. HE staining indicated that it could inhibit intimal thickening and reduce plaque formation. The above results indicated that leech may affect the protein expression of the p38MAPK signaling pathway to inhibit proliferation and promote the apoptosis of VSMCs via reducing blood lipid levels and suppressing TGF-ß1, aiming at inhibiting intimal thickening and reducing plaque formation, tand then slowing down the process of early atherosclerosis.
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Aterosclerosis/terapia , Sanguijuelas , Sistema de Señalización de MAP Quinasas , Músculo Liso Vascular/citología , Miocitos del Músculo Liso/efectos de los fármacos , Animales , Apoptosis , Caspasa 3/sangre , Proliferación Celular , Lípidos/sangre , MAP Quinasa Quinasa 3/metabolismo , Antígeno Nuclear de Célula en Proliferación/sangre , Proteínas Proto-Oncogénicas c-myc/metabolismo , Ratas , Factor de Crecimiento Transformador beta1/sangre , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Introduction: Herd immunity against norovirus (NoV) is poorly understood in terms of its serological properties and vaccine designs. The precise neutralizing serological features of genotype I (GI) NoV have not been studied. Methods: To expand insights on vaccine design and herd immunity of NoVs, seroprevalence and seroincidence of NoV genotypes GI.2, GI.3, and GI.9 were determined using blockade antibodies based on a 5-year longitudinal serosurveillance among 449 residents in Jidong community. Results: Correlation between human histo-blood group antigens (HBGAs) and GI NoV, and dynamic and persistency of antibodies were also analyzed. Seroprevalence of GI.2, GI.3, and GI.9 NoV were 15.1%-18.0%, 35.0%-38.8%, and 17.6%-22.0%; seroincidences were 10.0, 21.0, and 11.0 per 100.0 person-year from 2014 to 2018, respectively. Blockade antibodies positive to GI.2 and GI.3 NoV were significantly associated with HBGA phenotypes, including blood types A, B (excluding GI.3), and O+; Lewis phenotypes Leb+/Ley+ and Lea+b+/Lex+y+; and secretors. The overall decay rate of anti-GI.2 antibody was -5.9%/year (95% CI: -7.1% to -4.8%/year), which was significantly faster than that of GI.3 [-3.6%/year (95% CI: -4.6% to -2.6%/year)] and GI.9 strains [-4.0%/year (95% CI: -4.7% to -3.3%/year)]. The duration of anti-GI.2, GI.3, and GI.9 NoV antibodies estimated by generalized linear model (GLM) was approximately 2.3, 4.2, and 4.8 years, respectively. Discussion: In conclusion, enhanced community surveillance of GI NoV is needed, and even one-shot vaccine may provide coast-efficient health benefits against GI NoV infection.
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Norovirus , Vacunas , Humanos , Estudios Prospectivos , Estudios Seroepidemiológicos , Genotipo , Anticuerpos , Norovirus/genéticaRESUMEN
OBJECTIVES: In the present study, we used Activation Likelihood Estimation (ALE) meta-analysis to quantitatively examine brain grey matter reduction in schizophrenia patients with persistent negative symptoms (PNS). METHOD: A total of 12 voxel-based morphometry (VBM) studies were included in ALE meta-analysis using more stringent criterion of PNS. RESULTS: Significant grey matter reduction in the PNS group relative to controls was observed in the left caudate nucleus, the left precentral region, the left middle frontal region, the bilateral parahippocampal region, the left anterior cingulate region, the bilateral medial frontal gyrus, the thalamus and the insula. CONCLUSION: Our results suggest that brain regions in the reward network may be specifically related to PNS, especially the left caudate nucleus. It is possible that abnormality in reward processing may constitute the neural basis of PNS.
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Núcleo Caudado/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Esquizofrenia/diagnóstico por imagen , Psicología del Esquizofrénico , Núcleo Caudado/patología , Sustancia Gris/patología , Humanos , Tamaño de los Órganos , Esquizofrenia/patologíaRESUMEN
Impairments in spatial working memory (SWM) and set-shifting abilities have both been consistently observed in individuals with schizophrenia and are considered to be potential endophenotypes of this illness. However, an endophenotype needs to fulfill a set of stringent criteria, including heritability. This study examined the heritability of these two functions in a healthy Chinese twin sample. Forty-five pairs of monozygotic (MZ) twins and 35 pairs of dizygotic (DZ) twins completed the SWM task and the Intra-Extra Dimensional Set-Shifting (IED) task of the Cambridge Neuropsychological Test Automated Battery (CANTAB). We found a moderate heritability for SWM, of which the familial/genetic factors accounted for 33% of the total variance. However, we failed to find any significant heritability for set-shifting ability, of which the specific environmental factor explained most of the variance (85%). The preliminary findings from this small healthy Chinese twin sample suggest that SWM is heritable, whereas the set-shifting ability may reflect "extra-genetic" influences.
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Función Ejecutiva/fisiología , Memoria a Corto Plazo/fisiología , Memoria Espacial/fisiología , Adolescente , Adulto , China , Femenino , Humanos , Masculino , Gemelos Dicigóticos , Gemelos Monocigóticos , Adulto JovenRESUMEN
The Clinical Assessment Interview for Negative Symptoms (CAINS) was designed in accordance with the recent theory and research in social affective neuroscience and to address the psychometric and conceptual limitations of other instruments assessing negative symptoms. The present study aimed to provide a large-scale validation of the CAINS in China and examine its applicability and validity evidence across the schizophrenia spectrum. Using confirmatory factor analysis, our results replicated the original findings in the US development samples that the CAINS possesses a stable 2-factor structure, namely "motivation/pleasure" and "expression". We also found significant correlations between the CAINS and other negative symptom measures. The CAINS demonstrated good discriminant validity in differentiating negative symptoms in people with schizophrenia, nonpsychotic first-degree relatives and people with social anhedonia. People with schizophrenia exhibited significantly higher CAINS subscale scores than first-degree relatives and healthy controls. In addition, first-degree relatives had higher "motivation/pleasure" scores than healthy controls. The "motivation/pleasure" subscale scores of individuals with social anhedonia were also significantly higher than healthy controls.
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Anhedonia/fisiología , Entrevista Psicológica/normas , Escalas de Valoración Psiquiátrica/normas , Psicometría/métodos , Esquizofrenia/diagnóstico , Trastorno de la Personalidad Esquizotípica/diagnóstico , Adulto , China , Comparación Transcultural , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Esquizofrenia/fisiopatología , Trastorno de la Personalidad Esquizotípica/fisiopatologíaRESUMEN
Previous research has revealed anticipatory pleasure deficits in people with schizophrenia and people with social anhedonia but who do not have schizophrenia. Prospection is an important component of anticipatory pleasure, but little is known about the role of prospection in social anhedonia. In 2 studies, we investigated prospection and anticipatory pleasure in people with schizophrenia and people with social anhedonia using an affective prospection task and a self-report measure, the Temporal Experience of Pleasure Scale (TEPS). In Study 1, we found that people with schizophrenia (n = 31) reported less TEPS anticipatory pleasure, generated less rich and vivid prospections, and reported less preexperiencing of future events than people without schizophrenia (n = 29). In Study 2, we found that people with social anhedonia (n = 34) reported less TEPS anticipatory pleasure, generated less rich prospections, and reported less pleasure and preexperiencing for future events than people without social anhedonia (n = 33). Taken together, prospection impairments and decreased anticipatory pleasure were observed in schizophrenia and social anhedonia. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Asunto(s)
Anhedonia , Anticipación Psicológica , Placer , Psicología del Esquizofrénico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , AutoinformeRESUMEN
This study examined the factor structure of the Chinese version of the Dysexecutive Questionnaire (DEX) in a large nonclinical sample of college students (n = 1,586). All participants completed the self-report version of the DEX. An exploratory factor analysis was first performed on a sub-sample (randomly split, n = 766) and produced a four-factor model (Volition, Intentionality, Inhibition, and Abstract Problem-Solving), which was similar to previous models reported in Western samples. In addition, a series of confirmatory factor analyses was conducted on the remaining sample (n = 820). The findings suggested that a four-factor solution of the self-report DEX might better explain the latent structure in the present healthy Chinese sample.
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Pueblo Asiatico , Función Ejecutiva , Análisis Factorial , Encuestas y Cuestionarios , Adolescente , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Psicometría/estadística & datos numéricos , AutoinformeRESUMEN
OBJECTIVE: The present study aimed to validate a severity cut-off of negative symptoms for persistent negative symptoms (PNS) identification using the Clinical Assessment Interview for Negative Symptoms (CAINS). METHOD: A total of 206 patients with schizophrenia were recruited and divided into the PNS group (nâ¯=â¯57) and the Non-PNS group (nâ¯=â¯149) using PNS criteria based on the SANS and the SAPS. To determine the appropriate cut-offs on the CAINS in identifying PNS, Receiver Operating Characteristic (ROC) curve analysis was conducted in the PNS and Non-PNS groups. RESULTS: Our results showed that the cutoffs for identifying PNS on the CAINS total score, the Motivation and Pleasure (MAP) subscale score and the Expression (EXP) subscale score were 25, 17, and 5 respectively. Area Under the Curve (AUC) analysis indicated excellent discrimination of the PNS group from the Non-PNS group using the cut-off for the CAINS total score. However, discrimination was somewhat better for the MAP subscale score than the EXP subscale score. The Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of the MAP subscale were 81.54% and 97.16%. CONCLUSION: We found that the cut-off scores derived from the CAINS to identify PNS are comparable to existing scales. The CAINS offers an alternative means in identifying PNS patients in clinical trials that overcomes methodological and conceptual limitations of older scales.
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Esquizofrenia/diagnóstico , Adulto , Femenino , Humanos , Entrevista Psicológica , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Curva ROC , Esquizofrenia/tratamiento farmacológico , Psicología del EsquizofrénicoRESUMEN
Anhedonia in schizophrenia has been suggested to comprise a set of low-pleasure beliefs, defined as beliefs that certain things/activities were not pleasurable or that one does not feel pleasant generally. However, no instrument has been intentionally developed to specifically measure low-pleasure beliefs, and there is a paucity of empirical evidence for low-pleasure beliefs and their relationship with anhedonia in both patients with schizophrenia and individuals with high social anhedonia. We developed and validated the Beliefs About Pleasure Scale (BAPS) using non-clinical (Studies 1, 2 & 3), chronic schizophrenia (Study 2), and first episode schizophrenia (Study 3) samples. Across these studies, we examined psychometric properties of the BAPS, including temporal stability, internal consistency, factor structure, and convergent validity. The 22 BAPS items loaded onto 4 factors, namely the "Devaluation of Pleasure", the "Pleasurable Activity Expectancies", the "Negative Outcomes Expectancies", and the "Attention to Pleasure". The measure demonstrated good internal consistency and convergent validity in each sample. Moreover, both individual with schizophrenia and non-clinical participants with high social anhedonia scored higher on the BAPS than controls (Study 3), supporting construct validity. These findings provide preliminary evidence for the presence of low-pleasure beliefs in both clinical and subclinical groups and suggest that the BAPS has promising initial psychometric properties. The BAPS will be useful for exploring the cognitive component of anhedonia and provides a novel assessment for mechanism of change in psychosocial treatment studies.
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Anhedonia , Placer , Psicología del Esquizofrénico , Adolescente , Adulto , Cultura , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Psicometría , Reproducibilidad de los Resultados , Esquizofrenia/diagnóstico , Adulto JovenRESUMEN
BACKGROUND: Emotion deficits may be the basis of negative symptoms in schizophrenia patients and they are prevalent in these patients. However, inconsistent findings about emotion deficits in schizophrenia suggest that there may be subtypes. AIM: The present study aimed to examine and profile experiential pleasure, emotional regulation and expression in patients with schizophrenia. METHODS: A set of checklists specifically capturing experiential pleasure, emotional regulation, emotion expression, depressive symptoms and anhedonia were administered to 146 in-patients with schizophrenia and 73 demographically-matched healthy controls. Psychiatric symptoms and negative symptoms were also evaluated by a trained psychiatrist for patients with schizophrenia. RESULTS: Two-stage cluster analysis and discriminant function analysis were used to analyze the profile of these measures in patients with schizophrenia. We found a three-cluster solution. Cluster 1 (n=41) was characterized by a deficit in experiential pleasure and emotional regulation, Cluster 2 (n=47) was characterized by a general deficit in experiential pleasure, emotional regulation and emotion expression, and Cluster 3 (n=57) was characterized by a deficit in emotion expression. Results of a discriminant function analysis indicated that the three groups were reasonably discrete. CONCLUSION: The present findings suggest that schizophrenia patients can be classified into three subtypes based on experiential pleasure, emotional regulation and emotion expression, which are characterized by distinct clinical representations.
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Anhedonia/fisiología , Depresión/etiología , Placer/fisiología , Esquizofrenia/complicaciones , Psicología del Esquizofrénico , Adulto , Anticipación Psicológica , Análisis por Conglomerados , Depresión/diagnóstico , Análisis Discriminante , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , AutoinformeRESUMEN
Schizotypy is a set of personality traits that convey liability to develop schizophrenia. Studying schizotypy in healthy individuals may facilitate the understanding of the psychopathological processes underlying schizophrenia. The present study aimed to examine the developmental trajectories of schizotypy over time using a longitudinal study design. The Chapman Scales for Psychosis Proneness were administered to 1541 college students at baseline, and subsequently at six-monthly intervals up to 18months. Latent class growth analysis was conducted to track the different trajectories. In addition, self-reported scales were used to measure idea of reference, emotional experiences and expression, stress and coping, as well as social functioning. We identified four latent classes with distinct trajectories: "nonschizotypy" group (LC1), "stable high schizotypy" group (LC3), "high reactive schizotypy" group (LC2) and "low reactive schizotypy" group (LC4). These findings suggest that there may be distinct developmental trajectories for schizotypy. Two groups may be of particular interest: the "stable high schizotypy" group that displayed the worst clinical and functioning outcomes on almost all measures and the "high reactive schizotypy" group characterized by a relatively rapid decline in functioning.
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Trastornos del Humor/etiología , Trastorno de la Personalidad Esquizotípica/complicaciones , Trastorno de la Personalidad Esquizotípica/psicología , Conducta Social , Adaptación Psicológica , Adolescente , Análisis de Varianza , Femenino , Humanos , Estudios Longitudinales , Masculino , Escalas de Valoración Psiquiátrica , Psicometría , Factores de Tiempo , Adulto JovenRESUMEN
Social anhedonia, the reduced capacity for social and interpersonal pleasure, often accompanies several forms of psychopathology. The goal of the present study was to validate the Chinese translation of the Anticipatory and Consummatory Interpersonal Pleasure Scale (ACIPS), a promising new tool for the assessment of individual differences in social pleasure. The Chinese versions of the ACIPS, the Temporal Experience of Pleasure Scale (TEPS), and the Schizotypal Personality Questionnaire (SPQ) were administered to 389 nonclinical adults. Factor analysis revealed that a four-factor structure accounted for nearly 53% of the variance, and the factors were consistent with those identified from factor analyses of the ACIPS in Western (U.S.) samples. The ACIPS measure showed high internal consistency as well. Correlational analysis revealed evidence of convergent validity. Individuals who scored high on the ACIPS were more likely to score high on measures of anticipatory and consummatory pleasure. Moreover, ACIPS total scores were inversely associated with scores on the No Close Friends subscale and the Constricted Affect subscale of the Schizotypal Personality Questionnaire (SPQ). Taken together, the findings suggest that the Chinese translation of the ACIPS is a reliable, valid measure that can be used to assess individual differences in the capacity to experience social and interpersonal pleasure in Chinese individuals.
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Anhedonia , Placer , Psicometría , Adulto , Análisis Factorial , Femenino , Humanos , Masculino , Encuestas y CuestionariosRESUMEN
According to Meehl's model of schizotypy, there is a latent personality organization associated with the diathesis for schizophrenia that can be identified in several ways. We sought to examine the structural invariance of four Chapman psychosis-proneness scales (CPPS) across three groups of putative schizotypes, namely, clinically-, biologically-, and psychometrically-identified schizotypes. We examined the factor structure of the Perceptual Aberration (PER), Magical Ideation (MIS), Revised Social Anhedonia (RSAS), and Revised Physical Anhedonia (RPAS) scales in 196 schizophrenia patients, 197 non-psychotic first-degree relatives, and 1,724 non-clinical young adults. The confirmatory factor analyses indicated that the best-fitting model was one in which there is a two-factor model with negative schizotypy (RSAS and RPAS) and positive schizotypy (PER and MIS). All three samples fit the model well, with Comparative Fit Indices>0.95 and Tucker Lewis Indices>0.90. The root mean square error of approximations were all small (P values⩽0.01). We also observed that for both anhedonia scales, the groups' mean scale scores varied in the hypothesized direction, as predicted by Meehl's model of schizotypy. All three Chinese samples, namely, the patients (clinical schizotypes), relatives (biologically-identified schizotypes), and non-clinical young adults (containing psychometrically-identified schizotypes) showed the same factorial structure. This finding supports the suitability of the CPPS for cross-cultural and/or genetic investigations of schizotypy.