Neuraminic acid is involved in the binding of influenza C virus to erythrocytes

Neuraminidases of both viral and bacterial origin have been reported to be unable to destroy the cellular receptor for influenza C virus on chicken erythrocytes, in contrast to the receptors for influenza A and B virus. However, under appropriate conditions neuraminidases from both Vibrio cholerae and Clostridium perfringens were able (i) to make chicken red blood cells resistant against agglutination by influenza C virus and (ii) to reduce the hemagglutination-inhibiting activity of rat serum. Both effects were abolished in the presence of the neuraminidase inhibitor 2,3-dehydro-2-deoxyneuraminic acid (DDN). These results indicate that contrary to previous assumptions sialic acid may very well be an essential component of the receptor for influenza C virus.     

Methylenetetrahydrofolate reductase and spina bifida: evaluation of level of defect and maternal genotypic risk in Hispanics

The C677T and A1298C mutations in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene are each associated with reduced MTHFR activity. The C677T mutation in the heterozygous and homozygous state correlates with increased enzyme thermolability, with homozygous mutant genotypes showing significantly elevated plasma homocysteine levels and decreased plasma folate levels. The A1298C mutation results in decreased MTHFR activity, but changes in neither homocysteine nor folate levels are associated with A1298C variant genotypes. Our study determined the frequencies of the C677T and A1298C MTHFR mutations for spina bifida (SB) cases, mothers and fathers of SB cases, and controls in Hispanics of Mexican-American descent. In addition, our subject population was further categorized as to whether the spina bifida lesion occurred as an upper or lower level defect, according to the Van Allen "multi-site closure" model. Hispanic SB cases with upper level defects and their mothers were homozygous for the C677T variant allele at a higher rate than their respective controls (OR = 1.5 [95% CI 0.8-2.9], P = 0.30; OR = 2.3 [1.1-4.8], P = 0.04, respectively), with statistically significant results seen only for the maternal homozygous genotype. Homozygosity for the A1298C mutation was seen at a higher rate only in Hispanic mothers of both upper and lower level SB cases when compared to controls, but these results were not statistically significant. Our study provides evidence that the maternal C677T MTHFR homozygous mutant genotype is a risk factor for upper level spina bifida defects in Hispanics.     

Purification of influenza virus hemagglutinin by affinity chromatography

Summary Influenza virus or viral hemagglutinin could be purified on columns of agarose to which receptor substance from erythrocytes or fetuin had been conjugated. Hemagglutinin was eluted by elevating the salt concentration and temperature, while neuraminidase was kept inactive. These conditions permitted repeated use of the column.

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Zusammenfassung Influenzavirus oder virales Hämagglutinin konnte auf Agarose-Säulen gereinigt werden, an die Receptorsubstanz aus Erythrocyten oder Fetuin konjugiert worden war. Das Hämagglutinin wurde durch Erhöhung der Salzkonzentration und der Temperatur eluiert, während die Neuraminidase inaktiv gehalten wurde. Auf diese Weise ließen sich die Säulen wiederholt verwenden.

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The technical assistance of Mrs. H. Pahlich is gratefully acknowledged. The work was supported by the Sonderforschungsbereich 47 (Virologie).     

Emotional Exhaustion and Cognitive Performance in Apparently Healthy Teachers: A Longitudinal Multi‐source Study

We investigate how emotional exhaustion (EE), the core component of burnout, relates to cognitive performance, job performance and health. Cognitive performance was assessed by self‐rated cognitive stress symptoms, self‐rated and peer‐rated cognitive impairments in everyday tasks and a neuropsychological test of learning and memory (LGT‐3); job performance and physical health were gauged by self‐reports. Cross‐sectional linear regression analyses in a sample of 100 teachers confirm that EE is negatively related to cognitive performance as assessed by self‐rating and peer‐rating as well as neuropsychological testing (all p < .05). Longitudinal linear regression analyses confirm similar trends (p < .10) for self‐rated and peer‐rated cognitive performance. Executive control deficits might explain impaired cognitive performance in EE. In longitudinal analyses, EE also significantly predicts physical health. Contrary to our expectations, EE does not affect job performance. When reversed causation is tested, none of the outcome variables at Time 1 predict EE at Time 2. This speaks against cognitive dysfunctioning serving as a vulnerability factor for exhaustion. In sum, results underpin the negative consequences of EE for cognitive performance and health, which are relevant for individuals and organizations alike. In this way, findings might contribute to the understanding of the burnout syndrome. Copyright © 2012 John Wiley & Sons, Ltd.     

Emergence of enhanced attention to fearful faces between 5 and 7 months of age

The adult brain is endowed with mechanisms subserving enhanced processing of salient emotional and social cues. Stimuli associated with threat represent one such class of cues. Previous research suggests that preferential allocation of attention to social signals of threat (i.e. a preference for fearful over happy facial expressions) emerges during the second half of the first year. The present study was designed to determine the age of onset for infants’ attentional bias for fearful faces. Allocation of attention was studied by measuring event-related potentials (ERPs) and looking times (in a visual paired comparison task) to fearful and happy faces in 5- and 7-month-old infants. In 7-month-olds, the preferential allocation of attention to fearful faces was evident in both ERPs and looking times, i.e. the negative central mid-latency ERP amplitudes were more negative, and the looking times were longer for fearful than happy faces. No such differences were observed in the 5-month-olds. It is suggested that an enhanced sensitivity to facial signals of threat emerges between 5 and 7 months of age, and it may reflect functional development of the neural mechanisms involved in processing of emotionally significant stimuli.     

Use of the antibody neutralization test for detecting myoglobin in the urine in the diagnosis of myocardial infarction

A total of 230 patients admitted to Moscow city hospitals were examined to study the diagnostic value of a kit "Diagnosticum for the detection of erythrocytic myoglobin, dry". Myocardial infarction was diagnosed in 165 of them: in 138 it was transmural, in 27 intramural and in 65 the diagnosis was not confirmed (they were entered into the control group). Myoglobinuria was detected on the 1st day of transmural MI in 95%, on the 2nd day in 92% and on the 3rd day in 82%. In patients with intramural MI myoglobinuria was noted in 72% of the cases. In the control group the test was false positive in 9%.     

Borna disease, a progressive meningoencephalomyelitis as a model for CD4+ T cell-mediated immunopathology in the brain

A homogeneous T cell line NM1 with Borna disease (BD) virus reactivity could be established. The NM1 cells have been characterized as CD4+ T cells. Adoptive transfer revealed that this MHC class II-restricted immune cell is responsible for the immunopathological effect leading to BD, a progressive meningoencephalomyelitis.