Differences in cognitive functions between cytomegalovirus-infected and cytomegalovirus-free university students: a case control study
Chvatalova, V., Sebankova, B., Hrbackova, H., Turecek, P., Flegr, J
Scientific Reports 2018; 8: Artn 5322 10.1038/S41598-018-23637-3
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Cytomegalovirus (CMV) is the herpetic virus, which infects 45-100% people worldwide. Many reports suggest that CMV could impair cognitive functions of infected subjects. Here we searched for indices of effects of CMV on infected subjects' intelligence and knowledge. The Intelligence Structure Test I-S-T 2000 R was used to compare IQ of 148 CMV-infected and 135 CMV-free university students. Infected students expressed higher intelligence. Paradoxically, their IQ decreased with decreasing concentration of anti-CMV antibodies, which can be used, statistically, as a proxy of the time passed from the moment of infection in young subjects when the age of subjects is statistically controlled. The paradox of seemingly higher intelligence of CMV infected subjects could be explained by the presence of the subpopulation of about 5-10% CMV-positive individuals in the population of "CMV-negative students". These false negative subjects had probably not only the oldest infections and therefore the lowest concentration of anamnestic antibodies, but also the lowest intelligence among the infected students. Prevalence of CMV infection in all countries is very high, approaching sometimes 90%. Therefore, the total impact of CMV on human intelligence may be large.
Is toxoplasmosis a potential risk factor for liver cirrhosis?
El-Henawy, A. A., Razik, A. A., Zakaria, S., Elhammady, D., Saudy, N., Azab, M. S.
Asian Pacific Journal of Tropical Medicine 2015; 8: 768-775
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Objective: To document Toxoplasma gondii (T. gondii) antibody status in patients with liver disease, blood samples were taken from 180 hepatic patients and 180 healthy controls. Methods: Toxoplasma IgG antibody was detected using enzyme-linked immunosorbent assay and histopathological assessment of liver biopsy METAVIR score was applied. Results: Anti-T. gondii IgG antibodies were found in 32.8% of patients and in 22.2% of controls (P=0.02). Toxoplasma scropositivity was significantly associated with lymphadenopathy, history of blood transfusion and reflex impairment in patients. Chronic hepatitis C virus (HCV) and chronic HCV-related cirrhosis groups compared to chronic HBV and chronic HBV-related cirrhosis groups expressed significantly higher prevalence of T. gondii seropositivity (odds ratio (OR) =4; 95% confidence interval (CI): 1.3-12.6; P=0.013, OR=4.8; 95% CI: 1.5-14.9; P=0.006, respectively). Within the chronic HCV group, T. gondii seropositivity significantly associated disease evolution as regards to METAVIR histopathological system for fibrosis and inflammation (OR=19.4; 95% Cl: 2.3-165.2; P=0.0008, OR=0.29; 95% Cl: 0.1-0.8; P=0.01, respectively). Albumin, international normalized ratio (INR) and platelets count were the laboratory parameters significantly altered in Toxoplasma-positive chronic HCV patients (P=0.001, 0.03, 0.04, respectively). Child-Pugh scoring for cirrhosis in chronic HCV group placed the majority of seropositive patient in class C with significant statistical difference compared to Child A reference group (OR=0.08; 95% Cl 0.01-0.5; P=0.003). Conclusions: Toxoplasma seropositivity was high in patients with cirrhosis and associated higher grades of inflammation and necrosis signifying disease evolution, suggesting that cirrhotic patients may thus form a risk group for toxoplasmosis