1,141 research outputs found
Korean Dermatological Association and Korean Society for Investigative Dermatology: Brief History and Future Prospects
Korean dermatology began in the late
nineteenth century when American
missionary doctors introduced Western
medicine to Korea. Before the Second World
War, the medical system in general was similar
to the Japanese system; however, dermatologists
and their training institutes were few
in proportion to the total Korean population.
In this period, there were several pioneering
dermatologists, including Kung-Sun Oh.
An optimally evolved connective ratio of neural networks that maximizes the occurrence of synchronized bursting behavior
<p>Abstract</p> <p>Background</p> <p>Synchronized bursting activity (SBA) is a remarkable dynamical behavior in both <it>ex vivo </it>and <it>in vivo </it>neural networks. Investigations of the underlying structural characteristics associated with SBA are crucial to understanding the system-level regulatory mechanism of neural network behaviors.</p> <p>Results</p> <p>In this study, artificial pulsed neural networks were established using spike response models to capture fundamental dynamics of large scale <it>ex vivo </it>cortical networks. Network simulations with synaptic parameter perturbations showed the following two findings. (i) In a network with an excitatory ratio (ER) of 80-90%, its connective ratio (CR) was within a range of 10-30% when the occurrence of SBA reached the highest expectation. This result was consistent with the experimental observation in <it>ex vivo </it>neuronal networks, which were reported to possess a matured inhibitory synaptic ratio of 10-20% and a CR of 10-30%. (ii) No SBA occurred when a network does not contain any all-positive-interaction feedback loop (APFL) motif. In a neural network containing APFLs, the number of APFLs presented an optimal range corresponding to the maximal occurrence of SBA, which was very similar to the optimal CR.</p> <p>Conclusions</p> <p>In a neural network, the evolutionarily selected CR (10-30%) optimizes the occurrence of SBA, and APFL serves a pivotal network motif required to maximize the occurrence of SBA.</p
Quantitative evaluation and reversion analysis of the attractor landscapes of an intracellular regulatory network for colorectal cancer
The molecular profiles of CMS cancer cells, statistical significance analysis of reversion targets, and synergistic effect analysis of every two nodes inhibition. (XLSX 67Â kb
Investigations into the relationship between feedback loops and functional importance of a signal transduction network based on Boolean network modeling
<p>Abstract</p> <p>Background</p> <p>A number of studies on biological networks have been carried out to unravel the topological characteristics that can explain the functional importance of network nodes. For instance, connectivity, clustering coefficient, and shortest path length were previously proposed for this purpose. However, there is still a pressing need to investigate another topological measure that can better describe the functional importance of network nodes. In this respect, we considered a feedback loop which is ubiquitously found in various biological networks.</p> <p>Results</p> <p>We discovered that the number of feedback loops (NuFBL) is a crucial measure for evaluating the importance of a network node and verified this through a signal transduction network in the hippocampal CA1 neuron of mice as well as through generalized biological network models represented by Boolean networks. In particular, we observed that the proteins with a larger NuFBL are more likely to be essential and to evolve slowly in the hippocampal CA1 neuronal signal transduction network. Then, from extensive simulations based on the Boolean network models, we proved that a network node with the larger NuFBL is likely to be more important as the mutations of the initial state or the update rule of such a node made the network converge to a different attractor. These results led us to infer that such a strong positive correlation between the NuFBL and the importance of a network node might be an intrinsic principle of biological networks in view of network dynamics.</p> <p>Conclusion</p> <p>The presented analysis on topological characteristics of biological networks showed that the number of feedback loops is positively correlated with the functional importance of network nodes. This result also suggests the existence of unknown feedback loops around functionally important nodes in biological networks.</p
Robust supervisory control of timed discrete event systems under partial observation based on eligible time bounds: The existence conditions ଁ
Abstract This paper addresses a supervisory control problem for uncertain timed discrete event systems (DESs) under partial observation. An uncertain timed DES to be controlled is represented by a set of possible timed models based on the framework of Brandin and Wonham [(1994). Supervisory control of timed discrete event systems. IEEE Transactions on Automatic Control, 39(2), 329-342]. To avoid the state space explosion problem caused by tick events in the timed models, a notion of eligible time bounds is proposed for a single timed model obtained from the set of all possible timed models. Based on this notion, we present the necessary and sufficient conditions for the existence of a robust supervisor achieving a given language specification for the single timed model. Moreover, we show that the robust supervisor can also achieve the specification for any timed model in the set.
Role of Staphylococcal Superantigen in Atopic Dermatitis: Influence on Keratinocytes
Staphylococcus aureus may perform an crucial function in atopic dermatitis (AD), via the secretion of superantigens, including staphylococcal enterotoxins (SE) A or B, and toxic shock syndrome toxin-1 (TSST-1). Dysregulated cytokine production by keratinocytes (KCs) upon exposure to staphylococcal superantigens (SsAgs) may be principally involved in the pathophysiology of AD. We hypothesized that lesional KCs from AD may react differently to SsAgs compared to nonlesional skin or normal skin from nonatopics. We conducted a comparison of HLA-DR or CD1a expression in lesional skin as opposed to that in nonlesional or normal skin by immunohistochemistry (IHC). We also compared, using ELISA, the levels of IL-1α, IL-1β, and TNF-α secreted by cultured KCs from lesional, nonlesional, and normal skin, after the addition of SEA, SEB and TSST-1. IHC revealed that both HLA-DR and CD1a expression increased significantly in the epidermis of lesional skin versus nonlesional or normal skin in quite a similar manner. IL-1α, IL-1β, and TNF-α secretion was also significantly elevated in the cultured KCs from lesional skin after the addition of SsAgs. Our results indicated that KCs from lesional skin appear to react differently to SsAgs and increased proinflammatory cytokine production in response to SsAgs may contribute to the pathogenesis of AD
Proizvodnja antikomplementnih egzopolisaharida submerznim uzgojem gljive Flammulina velutipes
Seven species of basidiomycetes have been investigated for anti-complementary activity in hot water extracts and ethanol soluble fractions. Since Flammulina velutipes had the most potent activity, culture conditions for its mycelial growth were optimized to increase the production efficiency of anti-complementary exopolysaccharides. The optimal medium composition was (in g/L): galactose 15, sodium nitrate 5, glutamic acid 3, KH2PO4 2.5 and MgSO4·7H2O 0.6. Optimal production of anti-complementary activity was achieved at pH=3.5–5.5 and 25 °C. With these optimal medium and culture conditions, mycelial dry mass was maximized at 3.17 mg/mL after 6 days of cultivation in a 5-liter stirred-tank bioreactor, without pH control. The anti-complementary activity of exopolysaccharides increased sharply after 4 days of cultivation, and showed a high level at 5–6 days of cultivation. A periodate-labile carbohydrate moiety played a leading role in the anti-complementary activity exhibited by exopolysaccharide produced from F. velutipes. Results of tests on the anti-complementary activity in the absence of Ca²+ and immunoelectrophoresis indicated that the mode of complement activation by exopolysaccharide from F. velutipes is via both the classical and alternative pathways and that the activation degree is almost the same in each pathway.Istražena je antikomplementna aktivnost spojeva ekstrahiranih vrućom vodom i etanolom iz sedam vrsta gljiva stapčara. Optimirani su uvjeti uzgoja micelija gljive s najvećom aktivnosti, Flammulina velutipes, radi povećanja proizvodnje antikomplementnih egzopolisaharida. Optimalni sastav podloge bio je (u g/L): galaktoza 15, natrijev nitrat 5, glutamična kiselina 3, KH2PO4 2,5 i MgSO4·7H2O 0,6. Optimalna proizvodnja postignuta je pri pH=3,5-5,5 i 25 ºC. Pri tim uvjetima proizvedena je maksimalna količina suhe tvari od 3,17 mg/L nakon 6 dana uzgoja u bioreaktoru s miješalicom zapremnine 5 L, bez kontrole pH-vrijednosti. Antikomplementna aktivnost egzopolisaharida naglo se povećala nakon 4 dana, te je bila visoka nakon 5-6 dana uzgoja. Šećerni je ostatak, podložan djelovanju perjodata, glavni razlog antikomplementne aktivnosti egzopolisaharida gljive F. velutipes. Rezultati testiranja takve aktivnosti u odsutnosti Ca²+ iona i imunoelektroforeza upućuju na to da se komplementi egzopolisaharida iz F. velutipes aktiviraju klasičnim i alternativnim putem te da je stupanj aktivacije skoro jednak za oba puta
Paul's community formation in 1 Thessalonians : the creation of symbolic boundaries
This article presents how Paul, in 1 Thessalonians, executes the process of the formation of the
Thessalonian community. Using the sociological concept of symbolic boundaries, it is argued
that the resources – (1) the kerygmatic narrative, (2) the local narratives, and (3) the ethical
norms – that Paul incorporates into the letter take an essential role to promote the converts to
derive a cooperative identity from the community to which they belong and to strengthen the
distinction between them and the larger society. By providing internal consensus and external
separation, the resources serve to construct and maintain the Thessalonian community that is
internally united and externally distinct.This article is a reworked version of a section of the author’s larger research project in Practical Theology with specialisation in
Homiletics entitled: ‘Paul’s preaching for community formation in 1 Thessalonians: An alternative to the new homiletic’. It is being
written under the supervision of Cas Wepener and Ernest van Eck at the University of Pretoria.K.C. (University of Pretoria) was the PhD student. E.v.E.
(University of Pretoria) and C.W. (University of Pretoria)
acted as supervisors.http://www.hts.org.zaam201
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