University of Marburg

About: University of Marburg is a education organization based out in Marburg, Germany. It is known for research contribution in the topics: Population & Virus. The organization has 23195 authors who have published 42907 publications receiving 1506069 citations. The organization is also known as: Philipps University of Marburg & Philipps-Universität.

Apolipoprotein E is essential for amyloid deposition in the APP(V717F) transgenic mouse model of Alzheimer's disease.

Abstract: We quantified the amount of amyloid beta-peptide (Abeta) immunoreactivity as well as amyloid deposits in a large cohort of transgenic mice overexpressing the V717F human amyloid precursor protein (APP(V717F+/-) TG mice) with no, one, or two mouse apolipoprotein E (Apoe) alleles at various ages. Remarkably, no amyloid deposits were found in any brain region of APP(V717F+/-) Apoe(-/-) TG mice as old as 22 mo of age, whereas age-matched APP(V717F +/-) Apoe(+/-) and Apoe(+/+) TG mice display abundant amyloid deposition. The amount of Abeta immunoreactivity in the hippocampus was also markedly reduced in an Apoe gene dose-dependent manner (Apoe(+/+) > Apoe(+/-) >> Apoe(-/-)), and no Abeta immunoreactivity was detected in the cerebral cortex of APP(V717F+/-) Apoe(-/-) TG mice at any of the time points examined. The absence of apolipoprotein E protein (apoE) dramatically reduced the amount of both Abeta(1-40) and Abeta(1-42) immunoreactive deposits as well as the resulting astrogliosis and microgliosis normally observed in APP(V717F) TG mice. ApoE immunoreactivity was detected in a subset of Abeta immunoreactive deposits and in virtually all thioflavine-S-fluorescent amyloid deposits. Because the absence of apoE alters neither the transcription or translation of the APP(V717F) transgene nor its processing to Abeta peptide(s), we postulate that apoE promotes both the deposition and fibrillization of Abeta, ultimately affecting clearance of protease-resistant Abeta/apoE aggregates. ApoE appears to play an essential role in amyloid deposition in brain, one of the neuropathological hallmarks of Alzheimer's disease.

Mosaicism in Human Skin: Understanding the Patterns and Mechanisms

Abstract: Background: The skin is especially suitable for the study of mosaicism. In this review, the various genetic mechanisms leading to mosaicism and the resulting cutaneous patterns are considered. Observations: Mosaicism may produce different cutaneous patterns such as the lines of Blaschko, the checkerboard pattern, the phylloid pattern, and a patchy pattern without midline separation. A unique lateralization pattern is observed in the CHILD syndrome. Two major genetic categories are functional mosaics resulting from X inactivation and genomic mosaics caused by autosomal mutations. Functional mosaicism may be caused by either male-lethal or nonlethal X-linked mutations. Similarly, autosomal mutations resulting in genomic mosaicism may be either lethal or nonlethal. Many mosaics are caused by loss of heterozygosity, and uncommonly this mechanism may give rise to twin spots such as vascular twin nevi. Some cutaneous mosaic phenotypes virtually always occur sporadically, but exceptionally may show a familial aggregation. This paradox may be explained by paradominant inheritance. Heterozygous individuals are, as a rule, unaffected, but they express the birthmark when allelic loss occurs during embryogenesis. Conclusions: The concept of cutaneous mosaicism is important for gene mapping because here we have the opportunity to study two populations of cells differing only with regard to the mutation causing mosaicism. Future research will probably show that a specific genetic anomaly, when present as a mosaic, always produces the same type of cutaneous pattern. ( Arch Dermatol. 1993;129:1460-1470)

Li10SnP2S12: An Affordable Lithium Superionic Conductor

Abstract: The reaction of Li2S and P2S5 with Li4[SnS4], a recently discovered, good Li+ ion conductor, yields Li10SnP2S12, the thiostannate analogue of the record holder Li10GeP2S12 and the second compound of this class of superionic conductors with very high values of 7 mS/cm for the grain conductivity and 4 mS/cm for the total conductivity at 27 °C. The replacement of Ge by Sn should reduce the raw material cost by a factor of ∼3.