Antibodies in mother's milk protect children against giardiasis

The protective effect of anti-Giardia antibodies in mother's milk on the acquisition of Giardia infection in their children during the first 2 y of life was analysed as part of a prospective study on infant diarrhoea in a group of 307 mothers and children in Leòn, Nicaragua. Among 24 children acquiring infection within the first 6 months, 23 were born to mothers lacking antibodies. These children also developed more severe diarrhoea. A significant difference between children born to mothers with and without antibodies with respect to the age at which the first Giardia infection was acquired was demonstrated by survival analysis and log rank test (p = 0.036). In conclusion, children born to non-immune mothers are at significantly higher risk of acquiring Giardia infection and developing giardiasis with more severe symptoms compared with children of immune mothers.     

Lysosomal exoglycosidases in serum and urine of patients with colon adenocarcinoma

BACKGROUND/AIMS: The aim of this study is to evaluate the usefulness of determination the activity of lysosomal exoglycosidases: N-acetyl-beta-D-hexosaminidase (HEX - E.C. 3.2.1.30), beta-D-galactosidase (GAL - E.C. 3.2.1.23), alpha-L-fucosidase (FUC - E.C. 3.2.1.51) and alpha-D-mannosidase (MAN - E.C. 3.2.1.24) in blood serum and urine in diagnostics of colon adenocarcinoma. METHODOLOGY: The activity of lysosomal exoglycosidases was determined by the method of Marciniak et al. adapted to serum and urine of patients with adenocarcinoma of the colon. RESULTS: A significant increase in concentration of the activity of HEX, GAL and FUC was found in blood serum, as well as HEX and GAL in urine, of patients with colon adenocarcinoma, in comparison with healthy people. With the method of Marciniak et al. for determination the activity of HEX, GAL and FUC in blood serum as well as HEX and GAL in urine, the cases of colon adenocarcinoma were significantly differentiated from healthy people. CONCLUSIONS: The high diagnostic value, sensitivity and specificity of the method of Marciniak et al., suggests the possibility of its use for determination of the activity of HEX, FUC and GAL in blood serum as well as HEX and GAL in urine, in the diagnostics of colon adenocarcinoma.     

Stroop performance in normal control subjects: an fMRI study

In an attempt to clarify regional signal intensity changes, which may accompany the performance of the Stroop Color-Word task, healthy subjects were imaged using the fMRI BOLD technique while performing a modified version of the task. Both the AAA and VOA subdivisions of the anterior cingulate cortex were significantly activated during the interference condition; however, only the signal intensity change within the VOA correlated with task performance. Additionally, signal intensity change was significantly increased in the VOA subdivision of the cingulate cortex when controlling for signal intensity change present during the performance of a color naming task. This study extends previous findings by demonstrating that in healthy adults, a subdivision of the cingulate cortex is specifically associated with the cognitive demands present in the interference condition.     

Regulatory regions of the paraoxonase 1 (PON1) gene are associated with neovascular age-related macular degeneration (AMD)

Physiological stress response and oxidative damage are factors for aging processes and, as such, are thought to contribute to neovascular age-related macular degeneration (AMD). Paraoxonase 1 (PON1) is an enzyme that plays an important role in oxidative stress and aging. We investigated association of DNA sequence variants (SNP) within the upstream regulatory region of the PON1 gene with neovascular AMD in 305 patients and 288 controls. Four of the seven tested SNPs (rs705379, rs705381, rs854573, and rs757158) were more frequently found in AMD patients compared to controls (P = 0.0099, 0.0295, 0.0121, and 0.0256, respectively), and all but one (SNP rs757158) are in linkage disequilibrium. Furthermore, haplotype TGGCCTC conferred protection (odds ratio (OR) = 0.76, (CI) = 0.60–0.97) as it was more frequently found in control individuals, while haplotype CGATGCT increased the risk (OR = 1.55, CI = 1.09–2.21) for AMD. These results were also reflected when haplotypes for the untranscribed and the 5′untranslated regions (5′UTR) were analyzed separately. To assess haplotype correlation with levels of gene expression, the three SNPs within the 5′UTR were tested in a luciferase reporter assay. In retinal pigment epithelium-derived ARPE19 cells, we were able to measure significant differences in reporter levels, while this was not observed in kidney-derived HEK293 cells. The presence of the risk allele A (SNP rs705381) caused an increase in luciferase activity of approximately twofold. Our data support the view that inflammatory reactions mediated through anti-oxidative activity may be relevant to neovascular age-related macular degeneration.

Electronic supplementary material

The online version of this article (doi:10.1007/s11357-012-9467-x) contains supplementary material, which is available to authorized users.     

Carcinogenic effect of arsenate in C57BL/6J/Han mice and its modulation by different dietary selenium status

In this study, carcinogenic effects of arsenate in female C57BL/6J/Han mice exposed in drinking water to 50, 200 or 500 μg As/L for 24 months were investigated. All animals were fed low-selenium diet, however half of them were supplemented with sodium selenite in drinking water (200 μg Se/L) to ensure the normal dietary level of selenium. Glutathione peroxidase activity in erythrocytes and plasma as well as selenium concentration in plasma after 3, 6, 12 and 18 months in satellite groups showed considerable decrease in animals from non-selenium supplemented groups in comparison to supplemented groups. A clear arsenic concentration-dependent increase in the number of malignant lymphoma associated with increase in the risk of death was observed (hazard ratio=0.91, 1.46, and 2.24, for 50, 200 and 500 μg As/L, respectively). No significant influence of selenium dietary status on arsenic carcinogenicity was shown. A significant association between selenium supplementation status and increased risk of death of the animals from causes other than malignant tumors was found (HR=1.79, p=0.04).