Klaus Vieweg/Michael Winkler (Hrsg.): Bildung und Freiheit. Ein vergessener Zusammenhang. Paderborn: Schöningh, 2012[Rezension]

Rezension von: Klaus Vieweg/Michael Winkler (Hrsg.): Bildung und Freiheit. Ein vergessener Zusammenhang. Paderborn: Schöningh, 2012, 248 S., EUR 29,90

Recall Germinal Center and Antibody Responses

Repeated exposure to viruses or their antigens elicits anamnestic antibody responses that produce antibodies that are of greater magnitude and affinity compared to those induced after primary exposure to antigen.The anamnestic nature of the response is a result of the recall of memory Bcells (MBCs) that have undergone clonal expansion and affinity maturation in germinal centers(GCs) during the primary response. Upon antigen re-encounter (“boosting”), MBCs, aided by enhanced help from memory T cells, efficiently differentiate into antibody-secreting plasma cells

Challenging Youth: Establishing Supportive Relationships with Youth in South Los Angeles

Working with youth is a particular discipline, especially considering humanist ethical or life counseling. In order to support and empower marginalized youth one might ask which factors are important to establish a supportive relationship. How do professionals connect to the lived experiences and world of disadvantaged youth in order to reach, help, and support them? This is the central research question focused on practitioners working with disenfranchised youth in South Los Angeles. The study folds into two parts: 1) a theoretical account of published studies regarding adolescent development, the complex reality youth grow up in and factors that appear to be essential in establishing a relationship with teenagers; and 2) a report of empirical data from interviews with professionals who work with youth in a low-income community in Los Angeles and through experiences from volunteer work at the after-school program where these practitioners work. Both theoretical and practical perspectives illustrate that an integrated viewpoint is crucial to understand the complex reality in which teens construct and negotiate their identities. It is important to take all factors into consideration: from individual psychological aspects of a youth’s character, behavior, drives, etc. to the situational or contextual influences on various levels, including race, ethnicity, culture, gender, social class, the family and situation at home, etc. Thus, psychological theories need to be supplemented with socio-cultural perspectives. Together with pedagogical aspects of professional (inter) actions this forms an integrated paradigm. The integrated perspective provides a framework through which one can understand the developmental challenges youth encounter and connect to their lived experiences

DNA methylation and cognitive functioning in healthy older adults

Long-term supplementation with folic acid may improve cognitive performance in older individuals. The relationship between folate status and cognitive performance might be mediated by changes in methylation capacity, as methylation reactions are important for normal functioning of the brain. Although aberrant DNA methylation has been implicated in neurodevelopmental disorders, the relationship between DNA methylation status and non-pathological cognitive functioning in human subjects has not yet been investigated. The present study investigated the associations between global DNA methylation and key domains of cognitive functioning in healthy older adults. Global DNA methylation, defined as the percentage of methylated cytosine to total cytosine, was measured in leucocytes by liquid chromatography-MS/MS, in 215 men and women, aged 50-70 years, who participated in the Folic Acid and Carotid Intima-Media Thickness (FACIT) study (clinical trial registration number NCT00110604). Cognitive performance was assessed by means of the Visual Verbal Word Learning Task, the Stroop Colour-Word Interference Test, the Concept Shifting Test, the Letter-Digit Substitution Test and the Verbal Fluency Test. Using hierarchical linear regression analyses adjusted for age, sex, level of education, alcohol consumption, smoking status, physical activity, erythrocyte folate concentration and 5,10-methylenetetrahydrofolate reductase 677C→T genotype, we found that global DNA methylation was not related to cognitive performance on any of the domains measured. The present study results do not support the hypothesis that global DNA methylation, as measured in leucocytes, might be associated with cognitive functioning in healthy older individual

Serum Iron Parameters, HFE C282Y Genotype, and Cognitive Performance in Older Adults: Results From the FACIT Study

Although iron homeostasis is essential for brain functioning, the effects of iron levels on cognitive performance in older individuals have scarcely been investigated. In the present study, serum iron parameters and hemochromatosis (HFE) C282Y genotype were determined in 818 older individuals who participated in a 3-year randomized, placebo-controlled double-blind trial examining the effects of folic acid on carotid intima-media thickness. All participants had slightly elevated homocysteine levels and were vitamin B12 replete. Cognitive functioning was assessed at baseline and after 3 years by means of a neuropsychological test battery. At baseline, increased serum ferritin was associated with decreased sensorimotor speed, complex speed, and information-processing speed and increased serum iron was associated with decreased sensorimotor speed. Cognitive performance over 3 years was not associated with HFE C282Y genotype or iron parameters. In conclusion, serum iron parameters do not show a straightforward relationship with cognitive functioning, although elevated iron levels may decrease cognitive speed in older individuals susceptible to cognitive impairmen

Clusterin accumulates in synapses in Alzheimer’s disease and is increased in Apolipoprotein E4 carriers

One of the major challenges in developing effective therapeutic strategies for Alzheimer's disease is understanding how genetic risk factors contribute to neurodegeneration. The apolipoprotein epsilon 4 isoform ( APOE4) and variants in the Clusterin ( CLU) gene (also known as apolipoprotein J) are associated with increased risk of developing Alzheimer's. Our previous work demonstrated that APOE4 exacerbates synapse degeneration and synaptic accumulation of toxic oligomeric amyloid beta in human Alzheimer's and mouse models of disease. Here, we observe clusterin in synapses in human Alzheimer's disease brain. The percentage of synapses containing clusterin is higher in APOE4 carriers than APOE3 carriers. Furthermore, we observe oligomeric amyloid beta accumulation within synapses containing clusterin which is also higher in APOE4 carriers. These data link two genetic risk factors with synapse degeneration in Alzheimer's and support a potential role for clusterin working with APOE in causing synaptic damage. </p