48 research outputs found

    Evaluation rechnergestĂŒtzter Pflegedokumentation auf vier Pilotstationen (PIK-Studie 2000/2001)

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    Seit Jahren besteht der Wunsch, die Pflegedokumentation durch EDV-Einsatz zu unterstĂŒtzen, um die QualitĂ€t der Dokumentation zu erhöhen, AufwĂ€nde fĂŒr die PflegekrĂ€fte zu reduzieren, pflegerische AblĂ€ufe zu unterstĂŒtzen, und Auswertungsmöglichkeiten fĂŒr Pflegemanagement und Pflegeforschung zu verbessern. Die EinfĂŒhrung des rechnergestĂŒtzten Pflegedokumentationssystems PIK auf vier Pilotstationen am UniversitĂ€tsklinikum Heidelberg wird seit 1998 durch eine umfassende Evaluationsstudie begleitet. Ziel der Studie ist es, Erfolgsfaktoren und Auswirkungen rechnergestĂŒtzter Pflegedokumentationssysteme zu ermitteln, und Empfehlungen fĂŒr eine optimale EinfĂŒhrungsstrategie aufzustellen. Daher werden unter anderen die Auswirkungen der PIK-EinfĂŒhrung auf QualitĂ€t und VollstĂ€ndigkeit der Pflegedokumentation, auf die Akzeptanz des Pflegeprozesses, und auf die Akzeptanz von Computern allgemein und in der Pflege untersucht. Ausserdem werden die Akzeptanz von PIK bei pflegerischen und nicht-pflegerischen Mitarbeitern sowie die Auswirkungen auf die multiprofessionelle Kooperation berĂŒcksichtigt. Der vorliegende Forschungsbericht berichtet umfassend ĂŒber die Planung, DurchfĂŒhrung und Auswertung der Evaluation von PIK. Als Ergebnis der Studie wird unter AbwĂ€gung aller bisherigen Erkenntnisse empfohlen, ein rechnergestĂŒtztes Pflegedokumentationssystem mittelfristig am Klinikum Heidelberg einzufĂŒhren

    Altered Chromosomal Positioning, Compaction, and Gene Expression with a Lamin A/C Gene Mutation

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    Lamins A and C, encoded by the LMNA gene, are filamentous proteins that form the core scaffold of the nuclear lamina. Dominant LMNA gene mutations cause multiple human diseases including cardiac and skeletal myopathies. The nuclear lamina is thought to regulate gene expression by its direct interaction with chromatin. LMNA gene mutations may mediate disease by disrupting normal gene expression.To investigate the hypothesis that mutant lamin A/C changes the lamina's ability to interact with chromatin, we studied gene misexpression resulting from the cardiomyopathic LMNA E161K mutation and correlated this with changes in chromosome positioning. We identified clusters of misexpressed genes and examined the nuclear positioning of two such genomic clusters, each harboring genes relevant to striated muscle disease including LMO7 and MBNL2. Both gene clusters were found to be more centrally positioned in LMNA-mutant nuclei. Additionally, these loci were less compacted. In LMNA mutant heart and fibroblasts, we found that chromosome 13 had a disproportionately high fraction of misexpressed genes. Using three-dimensional fluorescence in situ hybridization we found that the entire territory of chromosome 13 was displaced towards the center of the nucleus in LMNA mutant fibroblasts. Additional cardiomyopathic LMNA gene mutations were also shown to have abnormal positioning of chromosome 13, although in the opposite direction.These data support a model in which LMNA mutations perturb the intranuclear positioning and compaction of chromosomal domains and provide a mechanism by which gene expression may be altered

    Multiple Novel Nesprin-1 and Nesprin-2 Variants Act as Versatile Tissue-Specific Intracellular Scaffolds

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    <div><h3>Background</h3><p>Nesprins (<u>N</u>uclear <u>e</u>nvelope <u>s</u>pectrin-<u>r</u>epeat <u>p</u>roteins) are a novel family of giant spectrin-repeat containing proteins. The nesprin-1 and nesprin-2 genes consist of 146 and 116 exons which encode proteins of ∌1mDa and ∌800 kDa is size respectively when all the exons are utilised in translation. However emerging data suggests that the nesprins have multiple alternative start and termination sites throughout their genes allowing the generation of smaller isoforms.</p> <h3>Results</h3><p>In this study we set out to identify novel alternatively transcribed nesprin variants by screening the EST database and by using RACE analysis to identify cDNA ends. These two methods provided potential hits for alternative start and termination sites that were validated by PCR and DNA sequencing. We show that these alternative sites are not only expressed in a tissue specific manner but by combining different sites together it is possible to create a wide array of nesprin variants. By cloning and expressing small novel nesprin variants into human fibroblasts and U2OS cells we show localization to actin stress-fibres, focal adhesions, microtubules, the nucleolus, nuclear matrix and the nuclear envelope (NE). Furthermore we show that the sub-cellular localization of individual nesprin variants can vary depending on the cell type, suggesting any single nesprin variant may have different functions in different cell types.</p> <h3>Conclusions</h3><p>These studies suggest nesprins act as highly versatile tissue specific intracellular protein scaffolds and identify potential novel functions for nesprins beyond cytoplasmic-nuclear coupling. These alternate functions may also account for the diverse range of disease phenotypes observed when these genes are mutated.</p> </div

    Uncoordinated Transcription and Compromised Muscle Function in the Lmna-Null Mouse Model of Emery-Dreifuss Muscular Dystrophy

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    LMNA encodes both lamin A and C: major components of the nuclear lamina. Mutations in LMNA underlie a range of tissue-specific degenerative diseases, including those that affect skeletal muscle, such as autosomal-Emery-Dreifuss muscular dystrophy (A-EDMD) and limb girdle muscular dystrophy 1B. Here, we examine the morphology and transcriptional activity of myonuclei, the structure of the myotendinous junction and the muscle contraction dynamics in the lmna-null mouse model of A-EDMD. We found that there were fewer myonuclei in lmna-null mice, of which ∌50% had morphological abnormalities. Assaying transcriptional activity by examining acetylated histone H3 and PABPN1 levels indicated that there was a lack of coordinated transcription between myonuclei lacking lamin A/C. Myonuclei with abnormal morphology and transcriptional activity were distributed along the length of the myofibre, but accumulated at the myotendinous junction. Indeed, in addition to the presence of abnormal myonuclei, the structure of the myotendinous junction was perturbed, with disorganised sarcomeres and reduced interdigitation with the tendon, together with lipid and collagen deposition. Functionally, muscle contraction became severely affected within weeks of birth, with specific force generation dropping as low as ∌65% and ∌27% of control values in the extensor digitorum longus and soleus muscles respectively. These observations illustrate the importance of lamin A/C for correct myonuclear function, which likely acts synergistically with myotendinous junction disorganisation in the development of A-EDMD, and the consequential reduction in force generation and muscle wasting

    Ćœena v jinĂœch kulturnĂ­ch perspektivĂĄch

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    The impact of mutations in the LMNA-gen on structure and function of the nucleus

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    Die Lamina ist ein Netzwerk aus Lamin-Proteinen und befindet sich unterhalb der inneren Kernmembran. Die Lamine A/C, die zu den Typ V IntermediĂ€rfilamenten gehören, spielen eine wichtige Rolle bei der Aufrechterhaltung der strukturellen IntegritĂ€t des Zellkernes sowie der Chromatinorganisation, der Transkription, der DNA-Replikation, der Differenzierung und der GenomstabilitĂ€t. In den letzten Jahren wurden ĂŒber 200 verschiedene Mutationen im Lamin A/C kodierenden LMNA Gen gefunden, die mehr als 10 unterschiedliche Krankheiten, die so genannten Laminopathien, auslösen können. Zu diesen Laminopathien zĂ€hlen unter anderem die Emery-Dreifuss-Muskeldystrophie (EDMD) und das Progerie-Syndrom. Die Mutation LMNA S143F In dieser Arbeit wurde zunĂ€chst die Punktmutation LMNA S143F, die in der N-terminalen DomĂ€ne des Lamin A/C lokalisiert ist, nĂ€her untersucht. Diese Mutation ist der Auslöser von einzigartigen phĂ€notypischen Merkmalen einer frĂŒhen Myopathie sowie einer Progerie. Strukturelle Analysen mit dem Elektronenmikroskop ergaben, dass die primĂ€ren dermalen Fibroblasten der Laminopathie-Patientin morphologisch verĂ€nderte Zellkerne hatten. In AbhĂ€ngigkeit von S143F Lamin A/C konnte in den Patientenfibroblasten eine abnormale Lokalisation der Kernproteine Nesprin2 Giant und den kĂŒrzeren Nesprin2-Isoformen nachgewiesen werden. DarĂŒber hinaus konnten wir beobachten, dass eine reduzierte Expression von Nesprin2 Giant eine Rolle bei der AusprĂ€gung der morphologischen Kerndeformationen spielte. Patientenzellen, die Nesprin2 Giant in hohem Maße exprimierten, zeigten keine Deformationen des Zellkerns und eine normale Verteilung verschiedener Kernproteine. FRAP-Analysen in vivo und biochemische Proteinextraktionsstudien des S143F-Lamin A/Cs in vitro zeigten eine verringerte MobilitĂ€t und Dynamik, sowie eine reduzierte Löslichkeit von S143F Lamin A/C gegenĂŒber wildtypischem Lamin A/C. Die Mutation LMNA S143F liegt im Außenbereich der coiled-coil-Struktur des Lamins. Dadurch fĂŒhrt der Austausch der neutralen AS Serin durch die große hydrophobe AS Phenylalanin nicht zu einer Störung in der Dimer-bildung, sondern zu einer Beeinflussung der Formierung zu Protofilamenten bzw. höheren Strukturen. Dies konnte durch in vitro Untersuchungen von rekonstituierten Parakristallen aus S143F Lamin A/C dargestellt werden, die eine VerĂ€nderung des transversalen BĂ€nderungs-musters aufwiesen. Zusammengenommen zeigen die Resultate, dass die Mutation LMNA S143F die Lamin-A-Polymerisation beeinflusst und dadurch die Dynamik und MobilitĂ€t der Typ A-Lamine beeintrĂ€chtigt. Außerdem konnte erstmals nachgewiesen werden, dass das Nesprin2 Giant Protein eine essentielle Rolle in der Pathogenese von Laminopathien einnimmt, indem es die Struktur des Zellkerns verstĂ€rkt und als struktureller „Gegenspieler“ zu Lamin A/C fungiert. Die Mutation LMNA R545C Die Punktmutation LMNA R545C, die in der C-terminalen DomĂ€ne des Lamin A/C lokalisiert, ist Auslöser eines sehr gravierenden PhĂ€notyps der autosomal dominanten Form der Emery- Dreifuss-Muskeldystrophie (AD-EDMD). Strukturelle Analysen ergaben, dass die primĂ€ren Myoblasten des EDMD-Patienten morphologisch verĂ€nderte Zellkerne haben. Ein Vergleich von deformierten Kernen aus Zellen mit verschiedenen Laminopathie-auslösenden Mutationen wie LMNA R545C, LMNA S143F und LMNA R377H zeigten allerdings, dass die untersuchten Mutationen nicht immer zu gleichen abnormalen PhĂ€notypen der Kernmorphologie, sondern zu divergenten AusprĂ€gungen der morphologischen KernverĂ€nderungen in Patientenzellen fĂŒhrten. Immunfluoreszenzanalysen ergaben, dass auch die Proteine Lamin A/C und Emerin in den Patientenzellen eine fehlerhafte Verteilung aufwiesen und „Honigwabenmuster“ ausbildeten. Interessanterweise konnte auch eine vom Alter der Zellen abhĂ€ngige Akkumulation der 20S-Untereinheit des Proteasoms in kleine nukleĂ€re Foci beobachtet werden. Diese Foci kolokalisierten weitgehend mit den promyelotischen LeukĂ€mie-Körperchen (PML). In den Patientenmyoblasten war der CDK-Inhibitor p21 stark angereichert, was ein Hinweis auf eine BeeintrĂ€chtigung der proteasomalen Funktion ist. Nach Kultivierung der Patientenmyoblasten in Minimalmedium zeigten diese eine eingeschrĂ€nkte FĂ€higkeit zur ex-vivo Differenzierung zu Myotuben. Dementsprechend war die Expression des Myogenese-spezifischen Transkriptionsfaktors Myogenin, sowie des Proliferationmarkers hypophosphoryliertes Retinoblastoma-Protein in Patientenmyoblasten nicht korrekt induziert. Zusammengenommen weisen diese Daten darauf hin, dass auch die Mutation LMNA R545C Einfluss auf die Kernarchitektur und -Proteinverteilung, die Chromatinorganisation, Gen-expression und Funktion des Proteasoms einnimmt. DarĂŒber hinaus beeintrĂ€chtigte die Mutation LMNA R545C die FĂ€higkeit zur korrekten Proliferation und Differenzierung der Myoblasten, welches eine potentielle Rolle in der Pathogenese von Laminopathien einnimmt.The nuclear lamina is a network of lamin polymers underlying the inner nuclear membrane. The lamins A/C, which are type V intermediatefilaments, are involved in the organisation of chromatin, gene regulation, DNA-replication, differentiation and the integrity of the genome. In recent years more than 200 mutations in the lamin A/C coding LMNA gene were discovered, which cause more than 10 genetic diseases, collectively termed as laminopathies. These laminopathies include the Emery-Dreifuss-muscular dystrophy (EDMD) and the progeria syndrome. The mutation LMNA S143F First we observed the S143F lamin A/C point mutation, located in the N-terminal domain of the lamin A/C. This mutation causes a phenotype combining features of myopathy and progeria. Structural analyses revealed that patient dermal fibroblast cells had dysmorphic nuclei containing numerous blebs and lobulations. The lamin S143F organization was altered, showing intranuclear and nuclear envelope aggregates and often presenting a honeycomb appearance. Subject to the S143F lamin A/C, there is a reduced expression and an altered distribution of nesprin2 giant and the shorter nesprin2 isoforms in patient fibroblasts. A subpopulation of mutant cells, however, expressing the nesprin2 giant isoform, did not show an overt nuclear phenotype. By contrast, nesprin2 giant deficient cells reveal an aberrant nuclear phenotype and a mislocalization of LAP2&#945; and the transcriptional active form of the RNA-Polymerase II. More detailed analyses of the S143F lamin A/C structure by FRAP-analysis in vivo and biochemical extraction studies in vitro revealed that S143F lamin is less dynamic and dissoluble compared to wildtype lamin A/C. The LMNA S143F mutation occupies the surface of the coiled-coil-structure of the lamin A/C. Thus, the structural topology and particularly the substitution by a bulky, hydrophobic amino acid do not affect the lamin A/C dimer structure but rather perturb intermolecular interactions. This was confirmed by in vitro analysis of reconstituted paracrystals of lamin A/C, which exhibited an altered transversal stratification-pattern. Beyond that, another question was, whether there is a formation of heteropolymers of wildtype and S143F lamin A/C and a formation of homopolymers in vivo. BIFC-analysis confirmed that wildtype and mutated lamins had the capacity to form heteropolymers and homopolymers in vivo. Moreover, the wildtype homopolymers and the lamin A/C-heteropolymers localized correctly in the nuclear envelope. In contrast, the formation of the S143F lamin A/C homopolymers influenced their correct localization in the nuclear envelope and lead to an aberrant nuclear morphology. The mutation LMNA R545C Myoblasts of patients developing a serious form of the autosomal dominant Emery-Dreifuss muscular dystrophy (AD-EDMD) in response to the R545C lamin A/C point mutation, located in the C-terminal domain, have been analyzed. Structural analyses revealed that subpopulations of these patient myoblast precursor cells had nuclear structural defects as lobulations, whose frequency increased with cell passages in culture. This overt phenotype was compared to other dysmorphic nuclei from laminopathy-causing mutations like LMNA S143F or LMNA R377H. These analyses pointed out, that each mutation leads to a specific nuclear phenotype. Immunofluorescence microscopy showed that the organisation of both lamin A/C and its inner nuclear membrane partner emerin were altered, showing a honeycomb appearance too. Furthermore, our data showed for the first time that in an EDMD context, a progressive accumulation of the 20S proteasomal core subunits into foci that largely colocalized with promyeolocytic leukemia bodies (PML) was obvious, as cells age in culture. Moreover, the impairment of proteasome function, as pointed out by p21 nuclear accumulation, may contribute to the high index of premature cellular senescence we observed in patient cells. Another signal concerning the premature senescence was the accumulation of heterochromatin in late passages and the one- to twofold increase of the nuclear volume of the patient myoblasts. When transferred into low serum medium, patient myoblasts expressing R545C mutated lamin A/C were deficient for ex-vivo differentiation into myotubes. Accordingly, the myogenesis transcription factor myogenin and the hypophosphorylated retinoblastoma-protein were not induced properly in patient myoblasts. These data suggest that the LMNA R545C mutation also affected the nuclear envelope architecture and the distribution of nuclear proteins, chromatin organization, gene expression and the proper function of the proteasome. Furthermore, the LMNA R545C mutation impaired both proliferation and differentiation capacities of myoblasts precursors as part of the pathogenesis of the AD-EDMD

    Sƈatky PƙemyslovcĆŻ aneb Jak si vybĂ­rali ĆŸenichy a nevěsty

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    Premysliden ruled over the Czech countries (Bohemia, Moravia, and Silesia) more than three hundred years (ca. 930–1306). They cooperated with the ruling houses of the neighbouring states (Hungary, Poland, Saxony, Bavaria, Austria etc.) as their political efforts as their marriage policy. The analysis of the Premysliden marriages indicated the existence of the rule of the exogamy, the rule of the preferential matrilateral cross cousin marriage, the rule of the long time systematic exchange of the women among two ruling houses. Example of the Premysliden marriage practice gives the idea of the search of the marriage rules existing in Europe during the early mediaeval centuries

    Podoby duchƯ a pƙedkƯ v západní Africe

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    The main theme of that essay is animism and its examples in the western Africa. The essay explains also the main differences between spirits and souls and describes theirs forms in the western Africa
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