Clinical Neuroscience

[Multilocus genetic analysis implicates neurodevelopment and immune system in the etiology of schizophrenia]

PULAY Attila József1, KOLLER Júlia2, NAGY László3, MOLNÁR Mária Judit1, RÉTHELYI János1,4

MARCH 30, 2017

Clinical Neuroscience - 2017;70(03-04)


[Background - Schizophrenia is a severe psychiatric disorder of poorly understood etiology, characterized by high heritability, multifactorial inheritance and high heterogeneity. Multilocus associaton methods may reduce the genetic heterogeneity and improve the probability of replication between analyses. Objectives - The aims of our study were twofold: 1. To analyse genetic risk factors of schizophrenia by using multilocus genetic tests. 2. To assess the replication probability attributable to the various multilocus tests. Subjects - Discovery set: case-parent trios of unaffected parents and affected probands with a DSM-IV schizophrenia diagnosis (n=16); replication set: schizophrenia cases and unaffected controls (n=5337). Methods - Associations of single nucleotide and indel markers were transferred to gene- and geneset-based associations, furthermore to geneset-enrichment tests and functional annotation cluster analyses in a two-staged designs. Associations with p<0.1 from the discovery set were tested in the replication sample. Familywise p-value correction for multiple comparisons were performed during the replication step. Results - After correction for multiplicity, no significant association or enrichment were detected for gene-based nor canonical pathway analyses, but significant association of the 14q31 cytoband and enrichments of the 5q31 and Xq13 cytobands were found (p_corr: 0.002, 0.006 and 0.048, respectively). Functional annotation clustering yielded statistically significant enrichment scores for clusters of splicing/alternative splicing, neurodevelopment and embryonic development. Improvements in replication probabilty were found with increased test complexity (P_rep: 0, 0.015, 0.21). Conclusions - Our results corroborate the involvement of neurodevelopment, synaptic plasticity and immune mechanisms in the etiology of schizophrenia. Also, our findings indicated improvement of replication probability by using multilocus genetic analyses. ]


  1. Semmelweis Egyetem, Pszichiátriai és Pszichoterápiás Klinika, Budapest
  2. Semmelweis Egyetem, Genomikai Medicina és Ritka Betegségek Intézete, Budapest
  3. Debreceni Egyetem, Biokémiai és Molekuláris Biológiai Intézet, Debrecen
  4. MTA-SE NAP-B Molekuláris Pszichiátriai és in vitro Betegségmodellezési Kutatócsoport, Budapest



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Procedural learning and its consolidation in autism spectrum disorder


Children with autism spectrum disorder (ASD) show altered learning and memory. A number of recent studies have debated whether procedural learning in ASD is intact or not. Our aim was to further assess the question of whether the implicit, non-conscious form of procedural learning in ASD children is intact or not, furthermore, how shifts towards a more explicit, attention-demanding task setting can alter this performance. We administered a modified version of the Alternating Serial Reaction Time (ASRT) Task to children with ASD and IQ- and age-matched typically developing (TD) children. The task consisted of alternating blocks of cued (explicit) and uncued (implicit probe) blocks, and was repeated after a 16-hour delay. We found that ASD and TD children showed similar sequence-specific learning in cued explicit blocks, however, on the uncued probe blocks ASD children performed better compared to TD children. After the 16-hour delay both groups showed retention of the previously acquired knowledge. Finally, when we investigated the performance in different parts of the blocks, we found that ASD children did not show an effect of fatigue by the second part of the blocks. Our results suggest that children with ASD have increased implicit procedural learning skills compared to TD children. Differences in cued (explicit) and uncued (implicit) settings indicate that children with ASD are not affected by the lack of explicit instructions in probe blocks, suggesting a resistance for changes in task settings. These findings can help in a more thorough planning of cognitive therapeutic setups for ASD children.

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[Relationship between sport and traumatic brain injury - risks and sequelaes]

TAMÁS Viktória, KOVÁCS Noémi, BÜKI András

[Traumatic brain injury represents major public health problem worldwide. A typical form of brain injuries is the injury suffered during sports, which according to severity ranges from mild injuries to fatal damages. The significance of the sport related minor head injuries derives form the high incidence, the excessive involvement of the younger age groups, and their potential repetitive nature. The repeated mild head injuries may accumulate, leading to complex structural, neurochemical, neuroendocrine, and psychological alterations, which in long term may result in changes of the patients quality of life and in significant deterioration of participation in the everyday activity. Actually we neither have enough knowledge about the ne-gative consequences, nor the way of prevention, or protection against the harmful long term results. With this study summary we would like to draw attention to the potential hazards emerging from sport injuries, moreover we would like to emphasize the importance of study participation and follow up of articles in this field.]

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Tuberous sclerosis complex (TSC) is an autosomal dominant disease due to the uncontrolled differentiation, proliferation, and migration of cells in several organs. Clinical expression is highly variable, from mild skin findings and asymptomatic brain lesions to seizures, mental retardation, autism, and potentially fatal kidney, cardiac, or pulmonary disease. Aim of this paper is to summarize the diagnostic criteria, surveillance and therapeutic issues of this multisystemic disorder emphasizing the most important neurological consequences. Presenting the state-of-the-art management recommendations and comparing them with the local protocols, we hope that our review might help in the proper assessment of one of the most important single gene disorder.

Clinical Neuroscience

[A családorvosok alvási apnoéval kapcsolatos ismeretei és attitűdjei. Megvalósul-e az OSAS szűrése a járművezetők egészségi alkalmasságának vizsgálata során?]


[Objective - Obstructive sleep apnea syndrome (OSAS) without treatment can cause serious cardiovascular, cardiorespiratory, neurological and other complications. Family physicians have an important role in recognizing the disease. The aim of the study is to assess the knowledge and attitude of family physicians related to sleep apnea. Whether OSAS screening is realized during the general medical checkup for drivers. Methods - In the cross-sectional study we used a validated OSAKA questionnaire in mandatory continuous medical education courses, supplemented with four additional questions. Results - 116 family physicians and 103 family medicine residents filled out the questionnaire. Hungarian family physicians, especially male doctors lack the adequate knowledge of sleep apnea. The average score of female physicians was significantly higher than that of males (13.4±1.8 vs. 11.7±2.6, p=0.005). The more sprecializations the doctor has, the higher the score. Zero or one special examination holders reached 12.5±2.3 points, two special examination holders 12.7±2.2 points. three or four special examination holders reached 14.0±2.1 (p=0.05). Residents’ average score was 12.1±2.4 points, which is higher than that of family doctors (p=0.012). Female residents also had higher average points than male residents (12.6±2.0 vs. 11.3±2.7; p=0.008). The size, location and type of the practice or the doctor’s age did not show any statistically significant correlation with the number of points achieved. According to our regression analysis, corrected to variables in the model, we found correlation between gender and medical knowledge, but there was no correlation between age, number of specialities, body mass index and the theoretical knowledge of the doctors. In terms of attitude female GPs had higher average scores than male GPs (3.5±0.6 vs. 2.9±0.6, p<0.001). Despite the modification of the 13/1992 regulation only 39% of the practices carried out regularly the required OSAS screening as part of the medical examination for a driving licence. Conclusions - Despite the high prevalence and clinical importance of OSAS, GPs often do not recognize sleep apnea and they have difficulty in treating their patients for this problem.]

Clinical Neuroscience

Electrophysiological alterations and general toxic signs obtained by subacute administration of titanium dioxide nanoparticles to the airways of rats

HORVÁTH Tamara, PAPP András, KOVÁCS Dávid, KÁLOMISTA Ildikó, KOZMA Gábor, VEZÉR Tünde

Introduction and aims - Particles of titanium dioxide (TiO2) with typical size below 100 nm have gained a broad range of application by now, partly involving direct human exposure. Their known properties - high specific surface, mobility within the organism, induction of oxidative stress, release of inflammation mediators etc. - raise the possibility of nervous system damage but the available data regarding this are scarce and contradictory. Based on that, and the experiences with other metal oxide nanoparticles, the aim of the present study was to investigate certain general end nervous system toxic effects of TiO2 nanoparticles applied in the airways of rats. Materials and methods - Young adult Wistar rats (5 groups of 10 rats each) received, daily for 28 days, intratracheal instillations of titanium dioxide nanoparticles of ca. 10 nm diameter, suspended in 1% hydroxyethyl cellulose dissolved in phosphate-buffered saline, in the doses of 1, 3, and 10 mg/kg b. w. Vehicle controls received the suspension medium and there was also an untreated control group. During treatment, the rats’ body weight was measured, and their clinical state observed, daily. After the 28 days, spontaneous cortical activity, sensory evoked potentials and tail nerve action potential was recorded in urethane anesthesia, then the rats were dissected and tissue samples were taken for Ti level determination and biochemical measurements of some oxidative stress indicators. Results - The two higher doses reduced the rate of body weight gain significantly. Sensory evoked potentials and tail nerve action potential were significantly slowed, but the change in the spectrum of spontaneous cortical activity was not significant. Correlation of moderate strength was found between certain evoked potential parameters and brain Ti level and oxidative stress data. Conclusion - Our results underlined the possible neurotoxicity of TiO2 NPs but also the need for further investigations.

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Clinical Neuroscience

Symptom profiles and parental bonding in homicidal versus non-violent male schizophrenia patients

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Clinical Neuroscience

[The application of RBANS (Repeatable Battery for the Assessment of Neuropsychological Status) in neurocognitive testing of patients suffering from schizophrenia and dementia]

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[Introduction - The purpose of our study was to find out whether the Hungarian adaptation of the RBANS (Repeatable Battery for the Assessment of Neuropsychological Status), a brief neurocognitive screening test, is appropriate for the differentation of healthy and non-healthy subject groups, or for the detection of differences between the cognitive performance of patient groups. Patients and method - The test battery was administrated to 38 healthy subjects, 69 schizophrenic patients, and 18 patients suffering from dementia (10 probable Alzheimer-type and eight vascular dementia). Results - There was a significant decrease of performance in all patient groups compared to the healthy group. In the schizophrenic group, the test indicated a deterioration of functioning in all cognitive areas. The patient group with Alzheimer-type dementia performed only slightly better than the schizophrenic group, because the fall of performance was not significant only one of the cognitive areas (in the visuo-spatial tasks) when compared to the healthy group. There was no difference between the performance of patients with vascular dementia and that of healthy subjects in direct memory, verbal and visuo-spatial tasks. The test results indicated an even deterioration of cognitive areas in patients with Alzheimer-type dementia. As for the vascular dementia group, the most vulnerable area proved to be that of attention, while their verbal functions were relatively spared. The deterioration in other cognitive functions shown by schizophrenic subjects was more moderate, but still significant. A comparison of the RBANS scores of the schizophrenic patients in our study and the result of an American study was also carried out. The global indeces showed no difference; only the pattern of the sub-scales was a little different. Conclusion - The Hungarian version of the RBANS seems appropriate for the differentiation of healthy and deteriorated cognitive performance in a Hungarian patient population.]

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[Clozapine - the last resort antipsychotic for treatment resistant schizophrenia ]


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Clinical Neuroscience

[Relationship between the efficacy of atypical antipsychotics and polymorphism of dopamine D3 receptor in schizophrenia]

SZEKERES György, JUHÁSZ Anna, KÉRI Szabolcs, RIMANÓCZY Ágnes, SZENDI István, SZABÓ Zoltán, JANKA Zoltán

[Object - Numerous relevant variants of dopamine receptors have been identified in schizophrenia. The Ser9Gly gene polymorphism of dopamine D3 receptor is known as a susceptibility factor for the disease. In addition, it has a role in the modification of therapeutic effect of antipsychotics. In this naturalistic study the authors investigated the relationship between this polymorphism and the therapeutic response to atypical antipsychotics. Method - 75 patients with schizophrenia according to DSM-IV and 45 healthy controlls were recruited. The patients were divided to responder and nonresponder subgroups, cut-off: >20 point improvement in Global Assessment of Functioning. By polymerase chain reaction the genotype of dopamine D3 receptor of every participant was determined. Results - The Ser9Ser genotype of dopamine D3 receptor was more frequent in the nonresponder subgroup (64%, p=0.0018). The Ser9 allele was overrepresented among nonresponder patients (82%, p=0.0172). Conclusion - Based on our results, the worse therapeutic response to atypical antipsychotics is associated with Ser9 variant of dopamine D3 receptor.]