Kai-Christian Sonntag

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Neural cells differentiated in vitro from human embryonic stem cells (hESC) exhibit broad cellular heterogeneity with respect to developmental stage and lineage specification. Here, we describe standard conditions for the use and discovery of markers for analysis and cell selection of hESC undergoing neuronal differentiation. To generate better-defined cell(More)
It is currently not known whether dopamine (DA) neurons derived from human embryonic stem cells (hESCs) can survive in vivo and alleviate symptoms in models of Parkinson disease (PD). Here, we report the use of Noggin (a bone morphogenic protein antagonist) to induce neuroectodermal cell development and increase the yield of DA neurons from hESCs. A(More)
Mutated intracellular huntingtin is widely expressed in tissues of Huntington's disease (HD) patients. Intraneuronal nuclear protein aggregates of mutant huntingtin are present in HD brains, suggesting a dysfunction of the ubiquitin proteasome system (UPS). Because many cells and tissues can cope with the abnormal gene effects while others dysfunction and(More)
In patients with Huntington's disease (HD), the proteolytic activity of the ubiquitin proteasome system (UPS) is reduced in the brain and other tissues. The pathological hallmark of HD is the intraneuronal nuclear protein aggregates of mutant huntingtin. We determined how to enhance UPS function and influence catalytic protein degradation and cell survival(More)
The nuclear transcription factor Nurr1 is involved in the development and maintenance of the midbrain dopaminergic (DA) neuronal phenotype. We analysed the cellular and biological effects of Nurr1 during embryonic stem (ES) cell differentiation using the ROSA26-engineered Tet-inducible ES cell line J1-rtTA that does not express transgenes in mature neurons.(More)
The origins of DNA replication of the genome (209 kbp) of Chilo iridescent virus (CIV), which is circularly permuted and terminally redundant, were identified. The defined genomic library of CIV, which represents 100% of DNA sequences of the viral genome (e.g., all 32EcoRI CIV DNA fragments), was used for transfection ofChoristoneura fumiferana insect cell(More)
Human embryonic and induced pluripotent stem cells are potential cell sources for regenerative approaches in Parkinson disease. Inductive differentiation protocols can generate midbrain dopamine neurons but result in heterogeneous cell mixtures. Therefore, selection strategies are necessary to obtain uniform dopamine cell populations. Here, we developed a(More)
Recently, it has been reported that hypochlorous acid (HOCl), a special product of neutrophil myeloperoxidase, degrades N-acetyl groups of N-acetylglucosamine, chondroitin sulfate, hyaluronic acid, and minced articular cartilage via a transient product to acetate. This work concerns 1H NMR investigations of synovial fluids of patients with rheumatoid(More)
Neurons obtained directly from human somatic cells hold great promise for disease modeling and drug screening. Available protocols rely on overexpression of transcription factors using integrative vectors and are often slow, complex, and inefficient. We report a fast and efficient approach for generating induced neural cells (iNCs) directly from human(More)
Two different mechanisms of inhibition of chemiluminescence in the oxidation of luminol by sodium hypochlorite were found. Most substances investigated in these experiments acted by scavenging NaOCl. This mechanism was independent of the concentration of hydrogen peroxide and the incubation time between luminol and inhibitors. The most potent inhibitors(More)