Surface antigenic changes in P.falciparum infected erythrocytes following treatment with Syk inhibitors and Artemisinin

The human Plasmodium falciparum (P.falciparum) parasite, currently infects more than 200 million people annually, causing about 500\u2009000 deaths a year and imposes considerable morbidity on the surviving population. Since 2001, the WHO has recommended Artemisinin based combination therapies (ACTs) as treatment of choice for falciparum malaria. However the WHO has observed foci of suspected artemisinin resistance in South- east Asia. Because strains of P. falciparum are rapidly emerging that are resistant to all known antimalarial drugs, including artemisinin, quinine, chloroquine, piperaquine, and mefloquine and their derivatives, emphasis is currently laid on comprehension of new therapies with novel mechanisms of action that includes also the patient\u2019s immune response. Delayed parasite clearance (DPC) has been identified as an useful indicator of artemisin resistance but it has been shown that parasite clearance suffers interindividual variability and reactivity to antimalarials may depend on host immunity. Recently, studies have demonstrated Syk Inhibitors (R406) as potentially useful new class of antimalarial drugs reducing parasitemia by two ways i) delaying P.falciparum growth and ii) suppressing merozoite egress. The latter is caused by interfering of Syk inhibitors with the membrane of the parasite harboring host RBC. Aim of this study is to understand whether the efficacy of new antimalarial combinations of Syk inhibitors and artemisinins (ARTs) is paralleled by enhanced immune responses of the host. I tried to identify a role of antimalarial drug treatment in the parasites clearance by host\u2019s innate immunity. To reach the goal, I studied the activating effect of Syk inhibitor R406, dihydroartemisinin (DHA) and the combination of both on cellular immune functions in in vitro experiments with human monocytes. First line defense mechanism against the malaria parasite, such as phagocytosis and oxidative burst were assessed in cultured primary phagocytes using ring-stage parasitized RBC as phagocytosis target without and with previous DHA and R406 treatment. The molecular basis for observed functional changes was investigated studying DHA- and R406-dependent opsonin-binding to ring-stage pRBCs. by flow cytometry, Western blotting and immune-precipitation. Monocytes show an increased phagocytosis level after treatment of parasitized Ring-PRBC with DHA and R406 and highest phagocytosis values when DHA and R406 were supplemented together at concentrations of 0.1uM and 0.5.uM, respectively. Membrane-bound autologous IgG and C3c complement factor were remarkably increased on Ring-PRBC surface after treatment with DHA and R406 as judged by flow cytometry. Immunoprecipitation confirmed Band 3 as main protein that is labelled by IgG in Syk-inhibitor treated pRBC and the decreased IgG/band 3 ratio in treated cells vs. untreated ones supports the band 3 aggregation model as signal for IgG flagging. Enhanced phagocytosis of PRBCs may represent the common mechanism for innate malaria protection in nonimmune individuals. Modifications on band 3 of host cell membranes accumulate by the oxidative challenge of the growing parasite accompanied by binding of haemichromes to the cytoplasmic tail of band 3. At the moment when a threshold of modifications is exceeded mainly at trophozoite stage PRBC are recognized by phagocytes and ingested. We hypothesize Syk kinase inhibitors to anticipate the moment of recognition by an early accumulation of modified band 3 and bound haemichromes already at ring stage. Syk inhibitors are described to specifically inhib phosphorylation used by PRBC to shed off band 3 \u2013 rich microparticles from their membrane. Consequently, DHA as radical producing molecule enhances the oxidative challenge in PRBC. In conclusion, my data support the hypothesis that Syk inhibitors are a promising class of antimalarial drugs that can suppress parasitemia by increasing also the antiparasitic immune defense. Particularly, R406 should not lead to the selection of resistant strains, as it targets host cell molecules and will likely avoid immunosuppressive effects of hemozoin due to the anticipated phagocytosis of Ring stage-PRBC. Therefore, Syk inhibitors may represent a strategic partner drug for artemisinin therapies for counteracting artemisinin resistance

Corrigendum: Child and adolescent behavior inventory (CABI): A new instrument for epidemiological studies and pre-clinical evaluation

Child and Adolescent Behavior Inventory (CABI): A New Instrument for Epidemiological Studies and Pre-Clinical Evaluation Clinical Practice & Epidemiology in Mental Health, 2013, 9: 51-61 Correction: Few corrections have been provided and replaced online in 15th, 20th, 21st and 22nd rows of the Appendix

Candidate biomarkers from the integration of methylation and gene expression in discordant autistic sibling pairs

While the genetics of autism spectrum disorders (ASD) has been intensively studied, resulting in the identification of over 100 putative risk genes, the epigenetics of ASD has received less attention, and results have been inconsistent across studies. We aimed to investigate the contribution of DNA methylation (DNAm) to the risk of ASD and identify candidate biomarkers arising from the interaction of epigenetic mechanisms with genotype, gene expression, and cellular proportions. We performed DNAm differential analysis using whole blood samples from 75 discordant sibling pairs of the Italian Autism Network collection and estimated their cellular composition. We studied the correlation between DNAm and gene expression accounting for the potential effects of different genotypes on DNAm. We showed that the proportion of NK cells was significantly reduced in ASD siblings suggesting an imbalance in their immune system. We identified differentially methylated regions (DMRs) involved in neurogenesis and synaptic organization. Among candidate loci for ASD, we detected a DMR mapping to CLEC11A (neighboring SHANK1) where DNAm and gene expression were significantly and negatively correlated, independently from genotype effects. As reported in previous studies, we confirmed the involvement of immune functions in the pathophysiology of ASD. Notwithstanding the complexity of the disorder, suitable biomarkers such as CLEC11A and its neighbor SHANK1 can be discovered using integrative analyses even with peripheral tissues

Coordination environment of Zn in foraminifera Elphidium aculeatum and Quinqueloculina seminula shells from a polluted site

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Child and Adolescent Behavior Inventory (CABI): Standardization for age 6-17 years and first clinical application

Background: The Child and Adolescent Behavior Inventory (CABI) is a questionnaire designed to collect information from the parents of children and adolescents, both for the preparation of screening and epidemiological studies and for clinical evaluation. It has been published in CPEMH in 2013, with the first data on 8-10 years old school children. Here we report an extended standardization on a school population 6-17 years old and the first results of the application in a clinical sample. Methods: Parents, after giving their informed consent, answered to the questionnaire. Complete and reliable data were obtained from the parents of 659 school children and adolescents 6-17 y.o., with a balanced distribution of gender. Moreover, in a population of 84 patients, the results with the CABI were compared with the clinical evaluation and the CBCL. Results: In the school population, scores were different in relation to gender and age. The values of externalizing disorders were higher in males, with the highest values for ADHD in the 6-10 y.o. children. On the contrary, the scores of internalizing disorders and of eating disorders tended to be slightly higher in females. In the clinical population, scores at the CABI were in agreement with the clinical evaluation in 84% cases for depressive symptoms (compared to CBCL 66%), 53% for anxiety symptoms (CBCL 42%) and 87% for ODD (CBCL 69%), differences, however; without statistical significance (chi square). Conclusion: The study obtained normative data for the CABI and gave information of the behavioral differences in relation to age and gender of the school population as evaluated by parents/caregivers. Clinically, the CABI provided useful information for the clinical evaluation of the patient, sometimes with better agreement with the final diagnosis compared to the CBCL