Anastasia N. Kastania

Delegate the smartphone user? Security awareness in smartphone platforms

Smartphone users increasingly download and install third-party applications from official application repositories. Attackers may use this centralized application delivery architecture as a security and privacy attack vector. This risk increases since application vetting mechanisms are often not in place and the user is delegated to authorize which functionality and protected resources are accessible by third-party applications. In this paper, we mount a survey to explore the security awareness of smartphone users who download applications from official application repositories (e.g. Google Play, Apples App Store, etc.). The survey findings suggest a security complacency, as the majority of users trust the app repository, security controls are not enabled or not added, and users disregard security during application selection and installation. As a response to this security complacency we built a prediction model to identify users who trust the app repository. The model is assessed, evaluated and proved to be statistically significant and efficient.

Reduced serum BDNF levels in patients with chronic schizophrenic disorder in relapse, who were treated with typical or atypical antipsychotics.

Brain-derived neurotrophic factor signals and dopaminergic function in the brain are strongly associated, and research on BDNF in schizophrenia may enhance our insights on the pathophysiological mechanisms of this disease. In the present study we aimed to investigate the possible association between serum BDNF levels and schizophrenic relapses and the possible differential effects of treatment with typical and atypical antipsychotics on serum BDNF levels in the same group of patients. We measured serum BDNF levels in 47 patients with schizophrenia during a relapse and again 6 weeks after administration of antipsychotic treatment (14 on risperidone, 18 on haloperidol, 10 on olanzapine and five on amisulpride) and in 44 healthy volunteers. Patients with schizophrenia showed reduced serum BDNF levels in relation to healthy volunteers at study entry. No significant differences were revealed in BDNF serum levels after 6 weeks of antipsychotic treatment in the patients compared to their own levels at study entry. However, serum BDNF was significantly increased in the subgroup receiving olanzapine compared to the other antipsychotics. Our findings may indicate a differential effect of olanzapine on BDNF levels compared to haloperidol, risperidone, and amisulpride.

Association of serum BDNF levels with hippocampal volumes in first psychotic episode drug-naive schizophrenic patients

Evidence suggests that hippocampal volumetric abnormalities are present in first-episode schizophrenia. The hippocampus contains the highest brain levels of neurotrophic factors, which are major determinants of neuronal plasticity. Brain-derived neurotrophic factor (BDNF) influences neuronal survival, differentiation, synaptogenesis, and maintenance and is also correlated with neuronal activation in the hippocampus. BDNF is also involved in the development and modulation of dopaminergic-related systems. Alterations of serum BDNF levels have been shown in a number of studies with first episode patients with schizophrenia, probably reflecting an association between BDNF and the pathogenesis of the disorder. In the present study we investigated the correlation between serum BDNF levels and hippocampal volumes in a sample of first episode drug-naïve patients with schizophrenia (FEP) and healthy control subjects. We found that hippocampal volume (HV) was decreased in FEP patients. Corrected right HV of FEP patients were significantly smaller compared to corrected right HVs of healthy subjects. The serum BDNF levels in the sample of FEP patients was significantly reduced compared to the healthy subjects. A significant positive association was found between serum BDNF and the corrected right HV in the group of patients such that the smaller the HV, the more reduced the serum BDNF levels. (Pearson r=0.452, p=0.045). Our findings indicate that low serum BDNF levels are associated with reduction in HV at the onset of schizophrenia and may further support the theory of a neuroprogressive-neurotoxic reaction associated with the onset of psychosis.

Global DNA hypomethylation-induced ΔNp73 transcriptional activation in non-small cell lung cancer

p73 possesses an extrinsic P1 promoter and an intrinsic P2 promoter controlling the expression of the pro-apoptotic TAp73 isoforms and the anti-apoptotic ΔΝp73 isoforms respectively. In this study, we investigated the DNA methylation status of both promoters as a means of epigenetic transcriptional control of their corresponding isoforms in 102 primary non-small cell lung carcinomas (NSCLCs). We demonstrated that while P1 hypermethylation-associated reduction of TAp73 mRNA levels is relatively infrequent, the P2 hypomethylation-associated over-expression of ΔΝp73 mRNA is a frequent event, particularly among squamous cell carcinomas. P2 hypomethylation strongly correlated with LINE-1 element hypomethylation, indicating that ΔΝp73 over-expression may be a passive consequence of global DNA hypomethylation.

Bladder cancer and arsenic through drinking water: A systematic review of epidemiologic evidence

Exposure to inorganic arsenic (As) through drinking water is a major international public health issue. We carried out a systematic review of the existing literature examining the association between the risk of bladder cancer in humans and exposure to arsenic through drinking water. We searched electronic databases for studies published from January 2000 up to April 2013. Eight ecological studies, six case-control studies, four cohort studies and two meta-analyses were identified. The vast majority of the studies were carried out in areas with high arsenic concentrations in drinking water such as southwestern and northeastern Taiwan, Pakistan, Bangladesh, Argentina (Cordoba Province), USA (southeastern Michigan, Florida, Idaho) and Chile. Most of the studies reported higher risks of bladder cancer incidence or mortality in areas with high arsenic concentrations in drinking water compared to the general population or a low arsenic exposed control group. The quality assessment showed that among the studies identified, arsenic exposure was assessed at the individual level only in half of them and only three assessed exposure using a biomarker. Further, five out of eight ecological studies presented results with adjustment for potential confounders except for age; all cohort and case-control studies presented results with adjustment for cigarette smoking status in the analysis. The majority of the studies with varying study designs carried out in different areas provided evidence of statistically siginificant increases in bladder cancer risk at high concentrations of arsenic (>50 μg L−1). Assessing bladder cancer risk at lower exposure concentrations requires further investigation.

State-of-the-art technology in modern computer-aided drug design

The quest for small drug-like compounds that selectively inhibit the function of biological targets has always been a major focus in the pharmaceutical industry and in academia as well. High-throughput screening of compound libraries requires time, cost and resources. Therefore, the use of alternative methods is necessary for facilitating lead discovery. Computational techniques that dock small molecules into macromolecular targets and predict the affinity and activity of the small molecule are widely used in drug design and discovery, and have become an integral part of the industrial and academic research. In this review, we present an overview of some state-of-the-art technologies in modern drug design that have been developed for expediting the search for novel drug candidates.

A Longitudinal Study of Alterations of Hippocampal Volumes and Serum BDNF Levels in Association to Atypical Antipsychotics in a Sample of First-Episode Patients with Schizophrenia

Background Schizophrenia is associated with structural and functional abnormalities of the hippocampus, which have been suggested to play an important role in the formation and emergence of schizophrenia syndrome. Patients with schizophrenia exhibit significant bilateral hippocampal volume reduction and progressive hippocampal volume decrease in first-episode patients with schizophrenia has been shown in many neuroimaging studies. Dysfunction of the neurotrophic system has been implicated in the pathophysiology of schizophrenia. The initiation of antipsychotic medication alters the levels of serum Brain Derived Neurotrophic Factor (BDNF) levels. However it is unclear whether treatment with antipsychotics is associated with alterations of hippocampal volume and BDNF levels. Methods In the present longitudinal study we investigated the association between serum BDNF levels and hippocampal volumes in a sample of fourteen first-episode drug-naïve patients with schizophrenia (FEP). MRI scans, BDNF and clinical measurements were performed twice: at baseline before the initiation of antipsychotic treatment and 8 months later, while the patients were receiving monotherapy with second generation antipsychotics (SGAs). Results We found that left hippocampal volume was decreased (corrected left HV [t = 2.977, df = 13, p = .011] at follow-up; We also found that the higher the BDNF levels change the higher were the differences of corrected left hippocampus after 8 months of treatment with atypical antipsychotics (Pearson r = 0.597, p = 0.024). Conclusions The association of BDNF with hippocampal volume alterations in schizophrenia merits further investigation and replication in larger longitudinal studies.

Association of the dopamine D3 receptor Ser9Gly and of the serotonin 2C receptor gene polymorphisms with tardive dyskinesia in Greeks with chronic schizophrenic disorder.

Association of the dopamine D3 receptor Ser9Gly and of the serotonin 2C receptor gene polymorphisms with tardive dyskinesia in Greeks with chronic schizophrenic disorder Emmanouil N. Rizos, Nikolaos Siafakas, Eleni Katsantoni, Vassiliki Lazou, Konstantinos Sakellaropoulos, Anastasia Kastania, Sophia Kossida, Kalliopi-Stavroula Chatzigeorgiou, Georgios Arsenis, Loukia Zerva, Konstantinos Katsafouros and Lefteris Lykouras

Association of Hypothalamic-Pituitary-Adrenal Axis-Related Polymorphisms with Stress in Asthmatic Children on Inhaled Corticosteroids

Objective: Long-term treatment of asthmatic children with low and moderate doses of inhaled corticosteroids (ICS) may result in mild adrenal suppression. Various associations have been shown between adrenal reactivity and single nucleotide polymorphisms (SNPs) related to the hypothalamic-pituitary-adrenal (HPA) axis. We aimed to investigate the genetic contribution of four HPA axis-related SNPs to the individual stress response when on ICS. Methods: The low dose Synacthen test was performed in 62 asthmatic children (43 males, median age 7.9 years) before and after 3 months of treatment with inhaled fluticasone (200 µg/day) or budesonide (400 µg/day). The SNPs determined were: rs1876828 and rs242941 in the corticotropin-releasing hormone receptor 1 (CRHR1) gene, T(-2C) in the promoter region of the melanocortin receptor 2 (MC2R) gene and BclI restriction fragment length polymorphsism in the glucocorticoid receptor (GR) gene. Results: Homozygotes for the variant rs242941 (TT) demonstrated a delayed cortisol response after treatment with ICS compared to heterozygotes (GT) (p = 0.033) and those with the wild-type (GG) genotype (p = 0.018). Homozygotes for the variant rs1876828 (AA) manifested lower baseline cortisol levels before treatment (p = 0.009) compared to the GG genotype and delayed cortisol response after treatment compared to the GA genotype (p = 0.05). BclI heterozygotes for the G allele (GC) demonstrated higher basal cortisol levels before and after treatment with ICS compared to homozygotes (CC) (p = 0.024, p = 0.018). Three SNP interactions were associated with serum cortisol levels. Conclusion: There is evidence of a contribution of HPA axis-related genetic variation to the stress response of asthmatic children on ICS. The clinical importance of this finding needs further elucidation.

Let-7, Mir-98 and Mir-181 as Biomarkers for Cancer and Schizophrenia

Recent evidence supports a role of microRNAs in cancer and psychiatric disorders such as schizophrenia and bipolar disorder, through their regulatory role on the expression of multiple genes. The rather rare co-morbidity of cancer and schizophrenia is an old hypothesis which needs further research on microRNAs as molecules that might exert their oncosuppressive or oncogenic activity in the context of their role in psychiatric disorders. The expression pattern of a variety of different microRNAs was investigated in patients (N = 6) suffering from schizophrenia termed control, patients with a solid tumor (N = 10) and patients with both schizophrenia and tumor (N = 8). miRNA profiling was performed on whole blood samples using the miRCURY LNA microRNA Array technology (6th & 7th generation). A subset of 3 microRNAs showed a statistically significant differential expression between the control and the study groups. Specifically, significant down-regulation of the let-7p-5p, miR-98-5p and of miR-183-5p in the study groups (tumor alone and tumorand schizophrenia) was observed (p<0.05). The results of the present study showed that let-7, miR-98 and miR-183 may play an important oncosuppressive role through their regulatory impact in gene expression irrespective of the presence of schizophrenia, although a larger sample size is required to validate these results. Nevertheless, further studies are warranted in order to highlight a possible role of these and other micro-RNAs in the molecular pathways of schizophrenia.