74 research outputs found
Gravimetrische und geodynamische Modellierungen in der Schwarmbeben-Region Vogtland/NW-Böhmen
Die Region Vogtland/NW-Böhmen zeichnet sich seismologisch durch das periodische Auftreten von Schwarmbeben aus. Als Ursache der Beben werden Interaktionen zwischen dem Spannungsfeld, Fluiden und einer speziellen Geometrie der geologischen Einheiten vermutet. Mittels eines hochauflösenden 3D gravimetrischen Untergrundmodells wurden besonders die tiefliegenden Strukturen der mittleren und unteren Kruste im Hinblick auf tektonische Störungen und eine Mantelaufwölbung bzw. ein Magmensystem an der Kruste/Mantel Grenze als mögliche Ursachen der Schwarmbeben untersucht. Die Verbindung zwischen Spannungsfeld und den geometrischen Besonderheiten der geologischen Strukturen im Untersuchungsgebiet wurde durch Modellierungen mittels der Finite-Elemente-Methode (FEM) analysiert. Die Resultate liefern einen Beitrag zur geowissenschaftlichen Gesamtinterpretation des Vogtlandes und seiner Umgebung
Q-SEA - a tool for quality assessment of ethics analyses conducted as part of health technology assessments
Introduction: Assessment of ethics issues is an important part of health technology assessments (HTA). However, in terms of existence of quality assessment tools, ethics for HTA is methodologically under-developed in comparison to other areas of HTA, such as clinical or cost effectiveness.Objective: To methodologically advance ethics for HTA by: (1) proposing and elaborating Q-SEA, the first instrument for quality assessment of ethics analyses, and (2) applying Q-SEA to a sample systematic review of ethics for HTA, in order to illustrate and facilitate its use. Methods: To develop a list of items for the Q-SEA instrument, we sys-tematically reviewed the literature on methodology in ethics for HTA, reviewed HTA organizations’ websites, and solicited views from 32 ex-perts in the field of ethics for HTA at two 2-day workshops. We sub-sequently refined Q-SEA through its application to an ethics analysis conducted for HTA.Results: Q-SEA instrument consists of two domains – the process do-main and the output domain. The process domain consists of 5 ele-ments: research question, literature search, inclusion/exclusion criteria, perspective, and ethics framework. The output domain consists of 5 elements: completeness, bias, implications, conceptual clarification, and conflicting values.Conclusion: Q-SEA is the first instrument for quality assessment of ethics analyses in HTA. Further refinements to the instrument to enhance its usability continue
Optimized Protocol for Proportionate CNS Cell Retrieval as a Versatile Platform for Cellular and Molecular Phenomapping in Aging and Neurodegeneration
Efficient purification of viable neural cells from the mature CNS has been historically challenging due to the heterogeneity of the inherent cell populations. Moreover, changes in cellular interconnections, membrane lipid and cholesterol compositions, compartment-specific biophysical properties, and intercellular space constituents demand technical adjustments for cell isolation at different stages of maturation and aging. Though such obstacles are addressed and partially overcome for embryonic premature and mature CNS tissues, procedural adaptations to an aged, progeroid, and degenerative CNS environment are underrepresented. Here, we describe a practical workflow for the acquisition and phenomapping of CNS neural cells at states of health, physiological and precocious aging, and genetically provoked neurodegeneration. Following recent, unprecedented evidence of post-mitotic cellular senescence (PoMiCS), the protocol appears suitable for such de novo characterization and phenotypic opposition to classical senescence. Technically, the protocol is rapid, efficient as for cellular yield and well preserves physiological cell proportions. It is suitable for a variety of downstream applications aiming at cell type-specific interrogations, including cell culture systems, Flow-FISH, flow cytometry/FACS, senescence studies, and retrieval of omic-scale DNA, RNA, and protein profiles. We expect suitability for transfer to other CNS targets and to a broad spectrum of engineered systems addressing aging, neurodegeneration, progeria, and senescence
Particle Size Distribution Measurements of Manganese-Doped ZnS Nanoparticles
We performed particle size and particle size distribution measurements for L-cysteine-stabilized ZnS/Mn nanoparticles in the size region below 10 nm. For this we applied transmission electron microscopy (TEM), analytical ultracentrifugation (AUC), dynamic light scattering (DLS), and asymmetric flow field flow fractionation (aF-FFF) measurements, and we calculated particle sizes with the help of X-ray diffraction (XRD) patterns and the shift of the band gap absorption in the UV-vis spectrum. The different methods are explained, and their limitations are discussed, with the conclusion that only a combination of different techniques can yield a realistic and complete picture about the size distribution of the sample. From these methods TEM, AUC, DLS, and aF-FFF measure the actual particle size distribution either in dispersion or after drying of the sample, whereas the particle size obtained from XRD patterns and with the help of the band gap widening corresponds to the average size of the crystal domains within the particles. We obtained particle size distributions with their maximum between 3 and 7 nm and a mean crystallite size of 3.5-4 nm
GIP receptor agonism improves dyslipidemia and atherosclerosis independently of body weight loss in preclinical mouse model for cardio-metabolic disease
BackgroundAgonism at the receptor for the glucose-dependent insulinotropic polypeptide (GIPR) is a key component of the novel unimolecular GIPR:GLP-1R co-agonists, which are among the most promising drugs in clinical development for the treatment of obesity and type 2 diabetes. The therapeutic effect of chronic GIPR agonism to treat dyslipidemia and thus to reduce the cardiovascular disease risk independently of body weight loss has not been explored yet.MethodsAfter 8 weeks on western diet, LDL receptor knockout (LDLR-/-) male mice were treated with daily subcutaneous injections of long-acting acylated GIP analog (acyl-GIP;10nmol/kg body weight) for 28 days. Body weight, food intake, whole-body composition were monitored throughout the study. Fasting blood glucose and intraperitoneal glucose tolerance test (ipGTT) were determined on day 21 of the study. Circulating lipid levels, lipoprotein profiles and atherosclerotic lesion size was assessed at the end of the study. Acyl-GIP effects on fat depots were determined by histology and transcriptomics.ResultsHerein we found that treatment with acyl-GIP reduced dyslipidemia and atherogenesis in male LDLR-/- mice. Acyl-GIP administration resulted in smaller adipocytes within the inguinal fat depot and RNAseq analysis of the latter revealed that acyl-GIP may improve dyslipidemia by directly modulating lipid metabolism in this fat depot.ConclusionsThis study identified an unanticipated efficacy of chronic GIPR agonism to improve dyslipidemia and cardiovascular disease independently of body weight loss, indicating that treatment with acyl-GIP may be a novel approach to alleviate cardiometabolic disease
Quantitative TaqMan® real-time PCR assays for gene expression normalisation in feline tissues
ABSTRACT: BACKGROUND: Gene expression analysis is an important tool in contemporary research, with real-time PCR as the method of choice for quantifying transcription levels. Co-analysis of suitable reference genes is crucial for accurate expression normalisation. Reference gene expression may vary, e.g., among species or tissues; thus, candidate genes must be tested prior to use in expression studies. The domestic cat is an important study subject in both medical research and veterinary medicine. The aim of the present study was to develop TaqMan(R) real-time PCR assays for eight potential reference genes and to test their applicability for feline samples, including blood, lymphoid, endocrine, and gastrointestinal tissues from healthy cats, and neoplastic tissues from FeLV-infected cats. RESULTS: RNA extraction from tissues was optimised for minimal genomic DNA (gDNA) contamination without use of a DNase treatment. Real-time PCR assays were established and optimised for v-abl Abelson murine leukaemia viral oncogene homolog (ABL), beta-actin (ACTB), beta-2-microglobulin (B2M), beta-glucuronidase (GUSB), hydroxymethyl-bilane synthase (HMBS), hypoxanthine phosphoribosyltransferase (HPRT), ribosomal protein S7 (RPS7), and tryptophan 5-monooxygenase activation protein, zeta polypeptide (YWHAZ). The presence of pseudogenes was confirmed for four of the eight investigated genes (ACTB, HPRT, RPS7, and YWHAZ). The assays were tested together with previously developed TaqMan(R) assays for feline glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and the universal 18S rRNA gene. Significant differences were found among the expression levels of the ten candidate reference genes, with a ~10;6-fold expression difference between the most abundant (18S rRNA) and the least abundant genes (ABL, GUSB, and HMBS). The expression stability determined by the geNorm and NormFinder programs differed significantly. Using the ANOVA-based NormFinder program, RPS7 was the most stable gene in the tissues studied, followed by ACTB and ABL; B2M, HPRT, and the 18S rRNA genes were the least stable ones. CONCLUSION: The reference gene expression stability varied considerably among the feline tissues investigated. No tested gene was optimal for normalisation in all tissues. For the majority of the tissues, two to three reference genes were necessary for accurate normalisation. The present study yields essential information on the correct choice of feline reference genes depending on the tissues analysed
SAND, a New Protein Family: From Nucleic Acid to Protein Structure and Function Prediction
As a result of genome, EST and cDNA sequencing projects, there are huge numbers of
predicted and/or partially characterised protein sequences compared with a relatively small
number of proteins with experimentally determined function and structure. Thus, there is a
considerable attention focused on the accurate prediction of gene function and structure
from sequence by using bioinformatics. In the course of our analysis of genomic sequence
from Fugu rubripes, we identified a novel gene, SAND, with significant sequence identity to
hypothetical proteins predicted in Saccharomyces cerevisiae, Schizosaccharomyces pombe,
Caenorhabditis elegans, a Drosophila melanogaster gene, and mouse and human cDNAs.
Here we identify a further SAND homologue in human and Arabidopsis thaliana by use of
standard computational tools. We describe the genomic organisation of SAND in these
evolutionarily divergent species and identify sequence homologues from EST database
searches confirming the expression of SAND in over 20 different eukaryotes. We confirm
the expression of two different SAND paralogues in mammals and determine expression of
one SAND in other vertebrates and eukaryotes. Furthermore, we predict structural
properties of SAND, and characterise conserved sequence motifs in this protein family
Extracellular Vesicles Derived from Osteogenic-Differentiated Human Bone Marrow-Derived Mesenchymal Cells Rescue Osteogenic Ability of Bone Marrow-Derived Mesenchymal Cells Impaired by Hypoxia
In orthopedics, musculoskeletal disorders, i.e., non-union of bone fractures or osteoporosis, can have common histories and symptoms related to pathological hypoxic conditions induced by aging, trauma or metabolic disorders. Here, we observed that hypoxic conditions (2% O2) suppressed the osteogenic differentiation of human bone marrow-derived mesenchymal cells (hBMSC) in vitro and simultaneously increased reactive oxygen species (ROS) production. We assumed that cellular origin and cargo of extracellular vesicles (EVs) affect the osteogenic differentiation capacity of hBMSCs cultured under different oxygen pressures. Proteomic analysis revealed that EVs isolated from osteogenic differentiated hBMSC cultured under hypoxia (hypo-osteo EVs) or under normoxia (norm-osteo EVs) contained distinct protein profiles. Extracellular matrix (ECM) components, antioxidants and pro-osteogenic proteins were decreased in hypo-osteo EVs. The proteomic analysis in our previous study revealed that under normoxic culture conditions, pro-osteogenic proteins and ECM components have higher concentrations in norm-osteo EVs than in EVs derived from naïve hBMSCs (norm-naïve EVs). When selected for further analysis, five anti-hypoxic proteins were significantly upregulated (response to hypoxia) in norm-osteo EVs. Three of them are characterized as antioxidant proteins. We performed qRT-PCR to verify the corresponding gene expression levels in the norm-osteo EVs’ and norm-naïve EVs’ parent cells cultured under normoxia. Moreover, we observed that norm-osteo EVs rescued the osteogenic ability of naïve hBMSCs cultured under hypoxia and reduced hypoxia-induced elevation of ROS production in osteogenic differentiated hBMSCs, presumably by inducing expression of anti-hypoxic/ antioxidant and pro-osteogenic genes
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