Schizophrenic Sample Research Articles

Persistent homology of fractional Gaussian noise.

In this paper, we employ the persistent homology (PH) technique to examine the topological properties of fractional Gaussian noise (fGn). We develop the weighted natural visibility graph algorithm, and the associated simplicial complexes through the filtration process are quantified by PH. The evolution of the homology group dimension represented by Betti numbers demonstrates a strong dependency on the Hurst exponent (H). The coefficients of the birth and death curves of the k-dimensional topological holes (k-holes) at a given threshold depend on H which is almost not affected by finite sample size. We show that the distribution function of a lifetime for k-holes decays exponentially and the corresponding slope is an increasing function versus H and, more interestingly, the sample size effect completely disappears in this quantity. The persistence entropy logarithmically grows with the size of the visibility graph of a system with almost H-dependent prefactors. On the contrary, the local statistical features are not able to determine the corresponding Hurst exponent of fGn data, while the moments of eigenvalue distribution (M_{n}) for n≥1 reveal a dependency on H, containing the sample size effect. Finally, the PH shows the correlated behavior of electroencephalography for both healthy and schizophrenic samples.

Regrouping scalets: Psychometric properties of the theory of mind picture stories task in a schizophrenic sample

ABSTRACT Theory of mind is one of the most intensively studied phenomena in the development of schizophrenic symptoms and impairments in social adjustment. Complex theory of mind processing requires both visual and verbal aspects of the social-perceptual and social-cognitive components of mind reading. Reliable assessment methods are considered essential for the proper conduct of research. The current study aims at investigating the psychometric properties of the Theory of Mind Picture Stories Task (ToM PST). Forty-seven patients with schizophrenia were enrolled in the study from three sites. Data from ToM PST were used for computing the consistency, reliability, and internal and construct validity of the test. Our preliminary findings showed less appropriate consistency. Therefore, we attempted to carry out structural changes on the task while preserving its scales and subscales, which measure crucial factors of ToM. The newly structured task has four scales. They show proper consistency (Sequencing: Cronbach's α = 0.70, Theory of a Single Person's Mind: α = 0.74, Switching Between Minds: α = 0.70, Comprehension of Misleading Behaviour: α = 0.67, Total: α = 0.80) with appropriate internal and construct validity, a moderate test-retest reliability over a four-month-course, and a proper inter-rater reliability.

Differential Expression Analysis on Schizophrenia Dataset Suggests Pseudogene RNU6-505P as under Selective Pressure

Schizophrenia is one of the 15 leading causes of disability worldwide. About 1% of the global population has schizophrenia, with 10% of premature mortality chance. Schizophrenia is therefore associated with significant health, social and economic concerns. In this context, thalamus and striatum areas play important roles as much in schizophrenia as processing information before reaching the conscious thought: step happening soon in the creativity action. Creativity is defined by psychological scientists as the generation of ideas or products that are both original and valuable. Creativity relies on imagination and this fundamental human ability remains understudied in comparison to other important psychological phenomena. It is natural to ask whether the gene expression profiling of samples from schizophrenic patients could highlight the activity of some genes specific to humans. Microarray analysis of the dataset GSE25673 revealed that the pseudogene RNU6-505P is expressed differentially in schizophrenic samples and correlates to CYP26A1, ARHGAP18, TSPAN12, HEY2 and TMEM132A genes. Ontological analysis showed that the RNU6-505P pseudogene is involved in brain development and certain neurological pathologies. Evolutionary analysis showed that the AGA 3-nucleotide sequence of RNU6-505P has been under positive selective pressure. Finally, the 1-nucleotide mutation prediction test revealed that variations on the AGA nucleotides could be fatal to the RNA structure of the sequence. We conclude that differential expression of the RNU6-505P pseudogene can be valid to diagnose schizophrenia and the RNU6-505P pseudogene may have a relevant function in the cerebral development and in the divergent evolution of humans from apes.

Comparative Dermatoglyphic Study Between Schizophrenic Patients and Healthy Controls

Introduction: Dermatoglyphics is the branch of medical science that is concerned with the study of dermal ridges present on fingers, palms, toes and the soles of the human being. There may have some association between fingerprints and schizophrenia regarding the developmental background of skin ridge pattern and brain.So this study was conducted to find out the fingerprint patterns in schizophrenic patients and also to find out sex variation of fingerprint patterns in between schizophrenic male and schizophrenic female.
 Objective: This study was carried out with a view to find out the fingerprint patterns in schizophrenic patients.
 Methodology: A total of 200 samples were selected. Among them, 100 were schizophrenic and 100 were normal healthy control. Samples were taken in between 15 to 40 years of age. Selection of schizophrenic sample was performed by a qualified psychiatrist. Fingerprints were taken by Ink and pad method, described by Cummins. Fingerprint patterns were observed by using a magnifying glass.
 Results: The frequency of common fingerprint pattern was reduced in schizophrenia. In healthy control loop pattern was predominant. But in schizophrenia frequency of loop pattern was reduced and there was an increased frequency of whorl and arch pattern.
 Conclusion: Asdermatoglyphics is genetically determined, predominant whorl and arch pattern found among the schizophrenic patients might provide a presumptive value which would aid in diagnosis of the disease.
 KYAMC Journal Vol. 10, No.-2, July 2019, Page 66-72

Validation du biais contre les indices infirmatoires chez un échantillon francophone de patients schizophrènes

PurposeThe purpose of this study was to verify the generality of the bias against disconfirmatory evidence in a French-speaking sample of schizophrenic patients. This bias is a heightened persistence of incorrect interpretations in front of contradictions, previously demonstrated in schizophrenic patients coming from non-French-speaking communities. MethodIn a pictorial decision task, 20 schizophrenic, 20 depressive and 20 control participants reappraised during eight successive steps, six interpretations proposed for emotionally neutral but initially incomplete pictures. Each step added a fragment of the picture represented. The reappraisal of the plausibility of incorrect interpretations between each step (change score [CS]) was measured for all the participants. The positive and negative symptoms scale as well as the scale for the assessment of positive symptoms were only administered to schizophrenic patients. ResultsEvolution of CS as a function of the seven last steps was significantly less pronounced in the schizophrenic samples. Only the negative dimension of the PANSS was correlated to the CS. DiscussionThese results replicated the BADE in a small French-speaking schizophrenic sample. The absence of a significant correlation between the BADE and the positive symptoms and measures of delusion was discussed with regard to both the small size of the sample and the explicative status of this bias.

Les limites de la Psychopathy Checklist-Revised (PCL-R) dans une population médico-légale souffrant de schizophrénie

AimThe Psychopathy Checklist-Revised (PCL-R) is the most studied and validated instrument to measure psychopathy. We aimed to explore its items content invariance to forensic schizophrenic subjects. MethodWe examined the PCL-R protocol of 15 male forensic schizophrenic subjects and attributed a score of sensitivity to psychotic symptomatology to each item score. ResultsResults suggest that the applicability of the PCL-R items to a forensic schizophrenic sample is not to be blindly warranted. Some items more systematically positively influenced by psychotic symptoms (e.g. Shallow Affect, Lack of Remorse or Guilt), while others were negatively influenced (e.g. Promiscuous Sexual Behavior, Glib and Superficial Charm), or not influenced at all (e.g. Criminal Versatility). ConclusionsThe current study suggest that the applicability of the PCL-R items to a forensic schizophrenic sample is not to be blindly warranted. We discuss both psychometric and conceptual implications for the measurement of psychopathy when a diagnosis of schizophrenia has been established.

The evidence for a birth order factor in schizophrenia.

The evidence for a birth order factor in schizophrenia is reviewed, and a paradoxical situation is revealed. Previous conclusions pointing to an over-representation of early born from small families and late born from large are confused by the report of a large sample of psychiatric patients by Hare and Price. This showed that similar distortions in birth order distribution occur in the non-schizophrenic patients to a greater extent than in the schizophrenic patients. An attempt is made to resolve this paradox. The reported distortions are assumed to be a feature of the general population. It is then hypothesized that they are diminished in the schizophrenic sample by a secondary over representation of another intermediate birth position. Evidence is given for a specific over-representation of the last-but-one position in schizophrenic samples.

Evaluation of Serum Apolipoprotein E as a Potential Biomarker for Pharmacological Therapeutic Efficacy Monitoring in Dopamine Dictated Disease Spectrum of Schizophrenia and Parkinson's disease: A Preliminary Study.

Aim of the Study:Parkinson’s disease and schizophrenia are disease end points of dopaminergic deficit and hyperactivity, respectively, in the mid brain. Accordingly, current medications aim to restore normal dopamine levels, overshooting of which results in adverse effects of psychosis and extra-pyramidal symptoms, respectively. There are currently no available laboratory tests to guide treatment decisions or help predict adverse side effects of the drugs. The aim was to therefore explore the possibility of using apolipoprotein E as a biomarker to monitor pharmacological intervention in dopamine dictated states of Parkinson’s disease and schizophrenia for optimum therapy.Methods:Naïve and treated, Parkinson’s disease and schizophrenic patients were recruited from neurology and psychiatry clinics. Serum of healthy volunteers was collected as controls. Serum concentrations of apolipoprotein E was estimated by enzyme-linked immunosorbent assay (ELISA). Pathway analysis was carried out to delineate the interactions of apolipoprotein E in Parkinson’s disease and schizophrenia.Results:Apolipoprotein E levels are higher in Parkinson’s disease patients as compared with schizophrenic samples (P < .05). Also, post-treatment apolipoprotein E levels in both disease states were at par with levels seen in healthy controls. The interactions of apolipoprotein E validate the results and place the differential expression of the protein in Parkinson’s disease and schizophrenia in the right perspective.Conclusion:Apolipoprotein E concentration across the dopaminergic spectrum suggests that it can be pursued not only as a potential biomarker in schizophrenia and Parkinson’s disease, but can also be an effective tool for clinicians to determine efficacy of drug-based therapy.

Face perception in schizophrenia: a specific deficit

ABSTRACTIntroduction. Patients with schizophrenia have a large-scaled and severe cognitive impairment. This study examines whether a well-established deficit in face recognition in schizophrenia is a part of this general cognitive impairment or is specific to faces per se.Method. The differential deficit in matching upright faces as compared with two psychometrically matched control tasks (matching inverted faces and matching none-face objects) was assessed in two well-matched samples of schizophrenics (n = 40) and controls (n = 40).Results. Indicating a generalised cognitive deficit, schizophrenics were impaired in all tasks. Importantly, however, the deficit in matching upright faces was stronger in magnitude (15.6%) than the deficits in matching inverted faces (10.1%) and non-face objects (10.2%). Consistently, schizophrenics showed weaker face inversion effects, indicating a configural processing dysfunction.Conclusion. These results provide compelling evidence for a face-specific deficit in schizophrenia that may be associated with, but separable from, a generalised cognitive impairment.

FT-IR spectroscopy and multivariate analysis as an auxiliary tool for diagnosis of mental disorders: Bipolar and schizophrenia cases

In this study, a methodology based on Fourier-transform infrared spectroscopy and principal component analysis and partial least square methods is proposed for the analysis of blood plasma samples in order to identify spectral changes correlated with some biomarkers associated with schizophrenia and bipolarity. Our main goal was to use the spectral information for the calibration of statistical models to discriminate and classify blood plasma samples belonging to bipolar and schizophrenic patients. IR spectra of 30 samples of blood plasma obtained from each, bipolar and schizophrenic patients and healthy control group were collected. The results obtained from principal component analysis (PCA) show a clear discrimination between the bipolar (BP), schizophrenic (SZ) and control group’ (CG) blood samples that also give possibility to identify three main regions that show the major differences correlated with both mental disorders (biomarkers). Furthermore, a model for the classification of the blood samples was calibrated using partial least square discriminant analysis (PLS-DA), allowing the correct classification of BP, SZ and CG samples. The results obtained applying this methodology suggest that it can be used as a complimentary diagnostic tool for the detection and discrimination of these mental diseases.

Comparison of serum BDNF levels in deficit and nondeficit chronic schizophrenia and healthy controls

The aim of this study was to compare serum BDNF levels of chronic schizophrenic patients, with or without deficit syndrome, and healthy controls. A comparative study of serum BDNF levels, determined by ELISA, was performed in 47 chronic patients with schizophrenia matched with 47 healthy controls. A part of the chronic schizophrenic sample was further divided into patients with a deficit (n=14) and a nondeficit syndrome (n=20), according to the Proxy for the Deficit Syndrome Scale. A significant difference was observed in decreased serum BDNF levels between chronic schizophrenia and healthy controls. No statistical significant differences in BDNF levels between deficit and nondeficit chronic schizophrenic patients were found. Our study confirms differences of serum BDNF levels of chronic schizophrenia and healthy controls, which correspond to the clinical progression of the disease. Our results do not support a relation between deficit profile in chronic schizophrenia and lower serum BDNF levels.

EPA-1794 – White matter changes in multi-episode schizophrenia: a longitudinal diffusion tensor imaging study

The aim of this study was to detect longitudinal differences in white matter brain structures in adults with schizophrenia compared to healthy controls. Twenty adult patients with multi-episode schizophrenia under stable antipsychotic medication and twenty-two age- and sex-matched healthy subjects were included in the study. Diffusion Tensor Imaging (DTI) was applied at baseline (t1), after 6weeks (t2) and after 3months (t3) and data processing was done with tract-based spatial statistics (p<0.05, corrected). Two subjects in the schizophrenic sample dropped out at t2 and one healthy subject at t3. Clinical and neuropsychological variables were measured and correlated with the most significant DTI findings. Compared with healthy age- and sex-matched controls schizophrenic patients showed widespread decreases in mean fractional anisotropy values (p<0.05, corrected). The most obvious FA decrease in the long-term was found in the anterior part of the corpus callosum (p<0.005, corrected), the left temporal lobe (p<0.004, corr.) and the mid-cingulate gyrus bilateral (p<0.004, corr.). Correlations to demographic variables, clinical rating scales (PANSS, CGI and GAF), verbal learning and memory and working memory will be presented. Magnetic resonance imaging was able to detect altered structural connectivity in patients with multi-episode schizophrenia in a longitudinal design.

Assessment of attention network efficiency in schizophrenic patients with positive and negative symptoms.

The aim of the present study was to examine the anterior (Experiment 1) and posterior (Experiment 2) attention systems in schizophrenic patients with predominantly negative or positive symptoms, in order to evidence possible differences in symptomatology. The schizophrenic sample was divided into two subgroups: negative(n=13) versus positive symptoms (n=10). The anterior and posterior attention systems in schizophrenic patients were assessed through two experiments: a dual-task paradigm evaluating executive functions, in particular planning and coordination,and a Simon task evaluating automatic shifting of visual attention. Our study showed specific attention deficits in the presence of negative symptoms. These findings suggest that negative schizophrenics have a deficit that affects functioning of both anterior and posterior attention systems, whereas positive schizophrenics showed a selective deficit only for the posterior attention system, with a pattern that is in the opposite direction compared to that of negative schizophrenics. Our results demonstrate that specific symptom dimensions or patterns are associated with specific cognitive impairments. Notably, negative schizophrenics exhibited clear abnormalities, whereas positive schizophrenics performed very similarly to healthy controls.

Peut-on prédire, dès l’enfance, les risques de développer la schizophrénie à l’âge adulte ? Une étude rétrospective centrée sur l’hypersensibilité prémorbide ; premiers résultats

It has been repeatedly found that 25 to 40% of the schizophrenic (SZ) patients had presented, in childhood, premorbid signs such as social withdrawal and minor neuro-psychological deficits. These signs were mainly found in patients with poor prognosis. Clinical indications suggest, however, that early premorbid sensitivity signs might exist in the whole population of SZ patients. The implications of such potential findings for treatment and prevention are evident. The aim of the study was to explore the nature and the importance of such signs and their potential value for prediction. MethodAs the premorbid schizophrenia signs that have been occasionally mentioned are often idiosyncratic and non specific, an exploratory inventory had to be done beforehand by exploring literature, clinical files, biographies, etc. This allowed the preparation of a 344 items questionnaire (about 3/4 of the questions relating to affectivity). The questions were organized according to a multi-choice design (generally five levels of intensity, from null to extreme). This exploratory questionnaire was retrospective and self-administered. PopulationThe questionnaire was answered by 29 families of adult SZ patients and of 27 Control (CT) subjects, paired by sex, age and socio-cultural level. ResultsThis paper presents the results for the 160 questions covering the ages from birth to the end of elementary school (∼ age 12). The most discriminative differences appeared from the visual comparison of the histograms of the responses intensity for SZ and for CT subjects. In about half of the cases, the histograms were similar, or quite similar, in the two populations (Fig. 1). But for 78 questions, the histograms (Fig. 2 et 3) revealed that the extreme levels of intensity were much more frequent in the SZ than in the CT population (table 1). This observation induced to credit each extreme response with a score, weighted according to the magnitude of this difference. Summing up the various scores of each subject made it possible to attribute individual scores. A score of 12 or more was found exclusively in the SZ sample (11 SZ, 0 CT); a score of 3 to<12 was found in 14 SZ and 3 CT; a negative (“normality”) score in 9 CT and 0 SZ. Conclusion and discussionThis exploratory sample of 29 reports on non symptomatic children who later became SZ, suggests that, beside defective premorbid signs in a minority of subjects, affective premorbid signs are present in most cases. Their tentative qualitative analysis suggests that pre-SZ children do not differ substantially from CT Ss with respect to common nervous features such as: Intrensic sleep characteristics, language mechanisms, emotivity and ordinary affectivity, including depression and culpability, etc. But, they are hypersensitive to some interpersonal situations: They might react excessively to the fear of losing attachments, of being unable to develop and defend a territory and to make social relationships. Combined eventually with developmental signs, affective premorbid signs could predict schizophrenia vulnerability. They could, also, provide clues to improved treatment of adult patients and, possibly, to preventive attempts. What make these non-specific signs potentially pre-SZ are: 1) their high intensity; and 2) their poorly organized accumulation in individual subjects (reflecting a disturbance of neural organization?). Alternatively, one third of the CT are correctly discriminated as “normal prone”. This, too, could inspire treatment and prevention. The coherence of the findings supports the validity of this retrospective study. However, the necessary duplication study is under way with a shorter list of questions and a larger number of subjects. From an ethical point of view, a public dissemination of these preliminary results would not be appropriate.

P-1217 - Duration of untreated illness (DUI) in the different schizophrenic subtypes: a collaborative study milan-moscow

Several studies show as a long duration of untreated illness (DUI) is associated with poor outcome in schizophrenic patients. Purpose of the present study was to evaluate eventual differences in terms of DUI between the diagnostic subtypes in a sample of schizophrenics coming from different geographic areas. One hundred twenty-five schizophrenic patients of the Psychiatric Clinic of Milan (n = 51) and Moscow (n = 74) were enrolled. SCID-I was administered to all patients and information about DUI were obtained consulting clinical charts, health system databases, and performing interviews with patients and their relatives. DUI was defined as the time between the onset of symptoms and the administration of first antipsychotic. One-way ANOVAs were performed to find eventual differences in terms of DUI between the diagnostic subtypes. Italian patients showed a longer DUI (4.14 years ± 4.95) in comparison with the Russian ones (1.16 years ±1.43). DUI was found to be longer in paranoid schizophrenics (3.47 years ± 4.19) respect to catatonic ones (0.96 years ± 0.94) (F = 3.56, p = 0.016). The results of the present study show as the different schizophrenic subtypes can have a different DUI perhaps for the dissimilar clinical severity and social functioning. Studies with larger samples are warranted to confirm the data of the present study.

Schizophrenia: Maternal inheritance and heteroplasmy of mtDNA mutations

Role of mitochondrial pathology in schizophrenia has not been fully clarified. We searched for distinctive variants in mtDNA extracted from the gray matter of postmortem brains and from peripheral blood samples. We screened mtDNA region containing 5 genes encoding subunits of cytochrome c oxidase and ATPases. Polymorphisms not already reported in databases are recorded as unregistered rare variants. Four unregistered, non-synonymous rare variants were detected in 4 schizophrenic samples. Seven registered non-synonymous variants were not previously detected in non-psychotic Japanese samples registered in the mtSNP database. These variants may contribute to disease pathophysiology. In one family, compound mutations showed co-segregation with schizophrenia. MtDNA mutations could confer a risk for schizophrenia in the Japanese population, although further analyses are needed.

A CAG repeat polymorphism of KCNN3 predicts SK3 channel function and cognitive performance in schizophrenia

KCNN3, encoding the small conductance calcium-activated potassium channel SK3, harbours a polymorphic CAG repeat in the amino-terminal coding region with yet unproven function. Hypothesizing that KCNN3 genotypes do not influence susceptibility to schizophrenia but modify its phenotype, we explored their contribution to specific schizophrenic symptoms. Using the Göttingen Research Association for Schizophrenia (GRAS) data collection of schizophrenic patients (n = 1074), we performed a phenotype-based genetic association study (PGAS) of KCNN3. We show that long CAG repeats in the schizophrenic sample are specifically associated with better performance in higher cognitive tasks, comprising the capacity to discriminate, select and execute (p < 0.0001). Long repeats reduce SK3 channel function, as we demonstrate by patch-clamping of transfected HEK293 cells. In contrast, modelling the opposite in mice, i.e. KCNN3 overexpression/channel hyperfunction, leads to selective deficits in higher brain functions comparable to those influenced by SK3 conductance in humans. To conclude, KCNN3 genotypes modify cognitive performance, shown here in a large sample of schizophrenic patients. Reduction of SK3 function may constitute a pharmacological target to improve cognition in schizophrenia and other conditions with cognitive impairment.

P300 amplitude is insensitive to working memory load in schizophrenia

BackgroundWorking memory (WM) tasks usually elicit a P300 ERP component, whose amplitude decreases with increasing WM load. So far, this effect has not been studied in schizophrenics (SZs), a group that is considered to have an aberrant brain connectivity and impairments in WM capacity. The aim of this study was to determine the dependency of the P300 component on WM load in a sample of SZ subjects.MethodsWe recorded 26 subjects (13 SZ patients and their matched controls) with an 80-channel electroencephalogram. Subjects performed an N-back task, a WM paradigm that manipulates the number of items to be stored in memory.ResultsIn healthy subjects, P300 amplitude was highest in the low WM load condition, and lowest in both the attentional control condition and the high WM load condition. In contrast, SZs evidenced low P300 amplitude in all conditions. A significant between group difference in P300 amplitude was evidenced only at the low WM load condition (1 -back), being smaller in SZs.ConclusionsSZ subjects display a lower than normal P300 amplitude, which does not vary as a function of memory load. These results are consistent with a general impairment in WM capacity in these patients.

Comparison of DRD2 rs1800497 (TaqIA) polymorphism between schizophrenic patients and healthy controls: Lack of association in a Turkish sample

Objective. The association of DRD2 rs1800497 (TaqIA) polymorphisms and schizophrenia has been studied in a number of populations, but the results are contradictory. We aimed to define Taq IA allelic differences between schizophrenic and healthy subjects. Methods. The schizophrenic group consisted of 99 schizophrenic inpatients, diagnosed and treated at Gazi University Hospital Psychiatry Service, the healthy group was composed of 109 subjects who did not suffer from any psychiatric or organic diseases. High molecular weight genomic DNAs were prepared from peripheral venous blood cells by using proteinase K digestion followed by salt extraction method. Target DNA amplification of DRD2 gene (Taq1A, 310-bp region) was performed by polymerase chain reaction (PCR) with the primers 5014 and 971. Results. Of the 208 subjects involved in the study, 98.6% had A1 allele (hetero- or homo-zygote) and 1.4% had A2 allele (homozygote). While all schizophrenia patients had A1 allele, 97.2%, of the healthy subjects (n=106) had A1 allele and there was no significant difference between the groups. Conclusion. This study was the first study related to DRD2 polymorphism conducted in a Turkish schizophrenic patient sample. A great percentage of our sample has A1 allele. Our study could not find a significant association between schizophrenia and DRD2 rs1800497 polymorphism.

The failure of the schizophrenia concept and the argument for its replacement by hebephrenia: applying the medical model for disease recognition

The failure of the schizophrenia concept and the argument for its replacement by hebephrenia: applying the medical model for disease recognition