81 research outputs found
Gesellschafterkompetenz in mittelstÀndischen Familienunternehmen
Die Corporate Governance Diskussion der letzten Jahre hat die Verantwortung der UnternehmensfĂŒhrung in den Mittelpunkt gestellt. FĂŒr mittelstĂ€ndische Familienunternehmen bedeutet dies, dass sie sich nicht nur ihrer Management-, sondern auch ihrer EigentĂŒmerverantwortung bewusst werden mĂŒssen. Mit der Entwicklung von Gesellschafterkompetenz könnten sie ihrer EigentĂŒmerverantwortung gezielt nachkommen. In der Praxis lĂ€sst sich dahingehend jedoch eine kaum systematische Vorgehensweise beobachten. Die Kompetenz der operativ tĂ€tigen Gesellschafter wird zwar wahrgenommen, spezifische MaĂnahmen zur Entwicklung von Gesellschafterkompetenz werden jedoch kaum ergriffen. Dies gilt insbesondere fĂŒr die nicht-operativ tĂ€tigen Gesellschafter und die Familienmitglieder, die ihre Gesellschafterrolle erst zukĂŒnftig wahrnehmen werden. Diese sollten nach der hier vertretenen Ansicht ebenfalls vorbereitet werden, indem sie in eine systematische Entwicklung von Gesellschafterkompetenz einbezogen werden. Neben den ĂŒblichen betriebswirtschaftlichen und rechtlichen Kompetenzen sollten auch Kenntnisse vermittelt werden, die der KomplexitĂ€t des Familienunternehmens gerecht werden.:1 Kompetenzverteilung in mittelstĂ€ndischen Familienunternehmen
2 Verantwortung der EigentĂŒmer
3 Systematische AnsÀtze fehlen
4 PluridisziplinÀres Know-how erwerben
5 LösungsansĂ€tze fĂŒr die Praxis
6 Fazit fĂŒr das mittelstĂ€ndische Familienunternehme
Associations between udder health and reproductive performance in United Kingdom dairy cows
The objective of this research was to evaluate the relationship between udder health and reproductive performance in UK dairy cows. Data from 80 herds were restructured such that each unit of data represented a 2-d period during lactation where a cow was at risk of becoming pregnant. Multilevel discrete-time survival models were then used within a Bayesian framework to explore associations between reproductive outcomes and a variety of potential explanatory variables. Separate models were constructed using 2 different univariate binary outcomes: a cow becoming pregnant during a risk period and a cow becoming pregnant as a result of a given service. Potential explanatory variables included occurrence of clinical mastitis and a categorical representation of individual cow somatic cell count (SCC), both at a variety of timings relative to the risk period. Posterior predictions were used to assess model fit and to check model building assumptions. These demonstrated that the model represented the data well. Within-sample Monte Carlo simulation (i.e., use of the model to predict outcomes for cases within the data set, repeated over a large number of iterations) was used to illustrate results as posterior predicted relative risks. A negative association was found between reproductive performance and cases of clinical mastitis over a wide time frame relative to the risk period (from 28â
d before to 70â
d after the risk period). A similar negative association with the probability of a service leading to a pregnancy (pregnancy rate) was observed over the same time frame. Higher SCC recordings (i.e., those more likely to be associated with an intramammary infection) were also associated with decreased reproductive performance, especially where an individual cow SCC of greater than 399,000/mL was recorded in the 30â
d following a risk period or service. This research demonstrates that both clinical and subclinical mastitis are associated with a reduction in reproductive performance, and that this influence varies in magnitude but can be exerted over a prolonged period
Molecular Regulation of Noradrenaline in Bovine Corpus Luteum
Noradrenergic stimulation increases progesterone, oxytocin and prostaglandins in the bovine luteal tissue. Better understanding of noradrenaline (NA) role in bovine the corpus luteum (CL) can advance our current knowledge on the regulatory mechanism of CL function. The present study was conducted to explore the source of noradrenaline and further to investigate whether nerve growth factor (NGF), insulin like growth factor 1 (IGF1) and transforming growth factor b1 (TGFb1) influence the expression of dopamine-b-hydroxylase (DBH), biosynthetic enzyme of NA in cultured bovine luteal cells. Corpora lutea were collected and classified into stages of early, developing, mid, late, and regressed. Messenger RNA (mRNA) and protein expression of DBH were studied throughout the estrous cycle. Additionally, DBH protein expression was examined in cultured mid luteal cells after tumour necrosis factor alpha/interferon gamma (TNFa/IFNg)-induced apoptosis or after treatment with NGF, IGF1, and TGFb1. DBH mRNA and protein expressions were detected throughout the cycle without significant changes in the protein level while mRNA showed a decrease at the developing stage (P < 0.05). Interestingly, NGF, IGF1, and TGFb1 increased DBH expression in cultured luteal cells (P < 0.05). The overall findings suggest non-neural source of noradrenaline in the bovine CL which appears to be regulated by NGF, IGF1, and TGFb1 indicating intraluteal molecules play an important and unrecognized role in the CL function
Selecting normalization genes for small diagnostic microarrays
BACKGROUND: Normalization of gene expression microarrays carrying thousands of genes is based on assumptions that do not hold for diagnostic microarrays carrying only few genes. Thus, applying standard microarray normalization strategies to diagnostic microarrays causes new normalization problems. RESULTS: In this paper we point out the differences of normalizing large microarrays and small diagnostic microarrays. We suggest to include additional normalization genes on the small diagnostic microarrays and propose two strategies for selecting them from genomewide microarray studies. The first is a data driven univariate selection of normalization genes. The second is multivariate and based on finding a balanced diagnostic signature. Finally, we compare both methods to standard normalization protocols known from large microarrays. CONCLUSION: Not including additional genes for normalization on small microarrays leads to a loss of diagnostic information. Using house keeping genes from the literature for normalization fails to work for certain datasets. While a data driven selection of additional normalization genes works well, the best results were obtained using a balanced signature
Helicobacter pylori Induction of the Gastrin Promoter Through GC-Rich DNA Elements
Helicobacter pylori ( H. pylori ) infection has been linked to the development of chronic gastritis, duodenal ulcer disease, and gastric cancer. Helicobacter pylori - infected patients and animal models develop hypergastrinemia, chronic gastritis, and gastric atrophy. Since gastrin is an important regulator of gastric acid secretion and cell growth, H. pylori regulation of this hormone has been implicated in its pathogenesis.To investigate the effect of H. pylori on gastrin gene expression in mice and of human bacterial isolates on gastrin mRNA expressed in a human cell line.Gastrin mRNA was measured by qRT-PCR in H. pylori -infected mice. H. pylori were co-cultured with AGS cells to study regulation of human gastrin gene expression. Various MAP kinases were implicated in signal transduction from the bacteria using specific inhibitors. Gastrin reporter constructs and gel shift assays were used to map DNA responsive elements.In addition to an increase in gastrin mRNA in H. pylori -infected mice, H. pylori induced the endogenous human gastrin gene through MAP kinase-dependent signaling but not NFÎșB-dependent signaling. Activation of gastrin through MAPK signaling did not require CagA or VacA virulence factors. Transfection studies demonstrated that a GC-rich motif mediated H. pylori -induction of the gastrin promoter and that the motif inducibly binds Sp1 and Sp3 transcription factors.Direct contact of live H. pylori bacteria with human cells is sufficient to induce gastrin gene expression.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79248/1/j.1523-5378.2010.00787.x.pd
Cancer reversion with oocyte extracts is mediated by cell cycle arrest and induction of tumour dormancy
Inducing stable control of tumour growth by tumour reversion is an alternative approach to cancer treatment when eradication of the disease cannot be achieved. The process requires re-establishment of normal control mechanisms that are lost in cancer cells so that abnormal proliferation can be halted. Embryonic environments can reset cellular programmes and we previously showed that axolotl oocyte extracts can reprogram breast cancer cells and reverse their tumorigenicity. In this study, we analysed the gene expression profiles of oocyte extract-treated tumour xenografts to show that tumour reprogramming involves cell cycle arrest and acquisition of a quiescent state. Tumour dormancy is associated with increased P27 expression, restoration of RB function and downregulation of mitogen-activated signalling pathways. We also show that the quiescent state is associated with increased levels of H4K20me3 and decreased H4K20me1, an epigenetic profile leading to chromatin compaction. The epigenetic reprogramming induced by oocyte extracts is required for RB hypophosphorylation and induction of P27 expression, both occurring during exposure to the extracts and stably maintained in reprogrammed tumour xenografts. Therefore, this study demonstrates the value of oocyte molecules for inducing tumour reversion and for the development of new chemoquiescence-based therapies
Negative energy balance in dairy cows is associated with specific changes in IGF-binding protein expression in the oviduct
Negative energy balance (NEB) during early lactation in dairy cows leads to an altered metabolic state that has major effects on the production of IGF family members. Low IGF-I concentrations are associated with poor fertility and therefore we aimed to determine whether NEB exerts a direct effect on IGF expression in the postpartum oviduct. Multiparous Holstein cows were allocated to two treatments (each n=6) designed using differential feeding and milking regimes to produce either mild NEB (MNEB) or severe NEB (SNEB). Animals were slaughtered in week 2 of lactation when divergent metabolic profiles were evident. Oviducts were collected for RNA analysis by real-time RT-PCR and in situ hybridisation. Quantitative measures in oviduct gene expression were obtained for all members of the IGF family (IGF-I/II, IGF-binding proteins (IGFBP) 1â6 and receptors for IGF types 1 and 2), insulin A/B, GH, glucocorticoid and oestrogen α/ÎČ. Expression of IGFBP-2 and IGFBP-6 (both of which have a high affinity for IGF-II) was decreased in SNEB relative to MNEB (P<0.05). No other gene was altered by NEB, but IGF-II, IGFBP-3, IGFBP-5 and IGFBP-6 all showed differential expression in different regions of the oviduct. These results indicate that, in addition to low circulating IGF-I after calving, NEB may also influence IGF availability in the oviduct indirectly through changes in specific IGFBP expression. It is possible that the predicted increased signalling by IGF-II may perturb embryo development, contributing to the high rates of embryonic mortality in dairy cows
Expression of costimulatory molecules in the bovine corpus luteum
BACKGROUND: Bovine luteal parenchymal cells express class II major histocompatibility complex (MHC) molecules and stimulate class II MHC-dependent activation of T cells in vitro. The ability of a class II MHC-expressing cell type to elicit a response from T cells in vivo is also dependent on expression of costimulatory molecules by the antigen presenting cell and delivery of a costimulatory signal to the T cell. Whether bovine luteal parenchymal cells express costimulatory molecules and can deliver the costimulatory signal is currently unknown. METHODS: Bovine luteal tissue was collected during the early (day 5; day of estrus = day 0), mid (day 11â12), or late (day 18) luteal phase of the estrous cycle, and at 0, 0.5, 1, 4, 12 or 24 hours following administration of PGF2alpha to cows on day 10 of the estrous cycle. Northern analysis was used to measure CD80 or CD86 mRNA concentrations in luteal tissue samples. Mixed luteal parenchymal cell cultures and purified luteal endothelial cell cultures were prepared, and real-time RT-PCR was used to examine the presence of CD80 and CD86 mRNA in each culture type. Monoclonal antibodies to CD80 and CD86 were added to a mixed luteal parenchymal cell-T cell co-culture in vitro T cell proliferation assay to assess the functional significance of costimulatory molecules on activation of T lymphocytes by luteal parenchymal cells. RESULTS: Northern analysis revealed CD80 and CD86 mRNAs in luteal tissue, with greatest steady-state concentrations at midcycle. CD80 and CD86 mRNAs were detected in mixed luteal parenchymal cell cultures, but only slight amounts of CD80 (and not CD86) mRNA were detected in cultures of luteal endothelial cells. Luteinizing hormone, PGF2alpha and TNF-alpha were without effect on concentrations of CD80 or CD86 mRNA in mixed luteal parenchymal cells cultures. Anti-CD80 or anti-CD86 monoclonal antibodies inhibited T cell proliferation in the in vitro T cell proliferation assay. CONCLUSION: It can be concluded from this study that parenchymal cells within the bovine CL express functional costimulatory molecules that facilitate interactions between with T cells, and these components of the antigen presentation pathway are expressed maximally in the midcycle CL
Transcriptomic analysis of a classical model of carbon catabolite regulation in Streptomyces coelicolor
Gesellschafterkompetenz in mittelstÀndischen Familienunternehmen
Die Corporate Governance Diskussion der letzten Jahre hat die Verantwortung der UnternehmensfĂŒhrung in den Mittelpunkt gestellt. FĂŒr mittelstĂ€ndische Familienunternehmen bedeutet dies, dass sie sich nicht nur ihrer Management-, sondern auch ihrer EigentĂŒmerverantwortung bewusst werden mĂŒssen. Mit der Entwicklung von Gesellschafterkompetenz könnten sie ihrer EigentĂŒmerverantwortung gezielt nachkommen. In der Praxis lĂ€sst sich dahingehend jedoch eine kaum systematische Vorgehensweise beobachten. Die Kompetenz der operativ tĂ€tigen Gesellschafter wird zwar wahrgenommen, spezifische MaĂnahmen zur Entwicklung von Gesellschafterkompetenz werden jedoch kaum ergriffen. Dies gilt insbesondere fĂŒr die nicht-operativ tĂ€tigen Gesellschafter und die Familienmitglieder, die ihre Gesellschafterrolle erst zukĂŒnftig wahrnehmen werden. Diese sollten nach der hier vertretenen Ansicht ebenfalls vorbereitet werden, indem sie in eine systematische Entwicklung von Gesellschafterkompetenz einbezogen werden. Neben den ĂŒblichen betriebswirtschaftlichen und rechtlichen Kompetenzen sollten auch Kenntnisse vermittelt werden, die der KomplexitĂ€t des Familienunternehmens gerecht werden.:1 Kompetenzverteilung in mittelstĂ€ndischen Familienunternehmen
2 Verantwortung der EigentĂŒmer
3 Systematische AnsÀtze fehlen
4 PluridisziplinÀres Know-how erwerben
5 LösungsansĂ€tze fĂŒr die Praxis
6 Fazit fĂŒr das mittelstĂ€ndische Familienunternehme
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