451 research outputs found
The developmental process of flood shoals based on observations in Toufutsu lake, Japan
Recently, the flood tidal sand bars have been developed at the entrance channel of Toufutsu Lake located along Okhotsk Sea in Hokkaido, and they affect flood control, inland water fisheries in lake, and so forth. In this study, we aimed to reveal the developmental process of sand bars by observations, which are velocity observation, water level observation, bed material investigation and video monitoring. Followings were major accomplishments of this study. (1) The maximum magnitude of reverse velocity at St.400 in the entrance channel during the periods of flood-tide was faster than that of normal velocity during the periods of ebb-tide. (2) The relationship between velocity at SP400 and friction velocity at SP400 during the periods of flood-tide is different from that during the periods of ebb-tide. (3) The\ud
flood tidal sand bars at the entrance channel of Toufutsu Lake were developed by not only sea waves, but also adverse tidal current in the spring-tide
Review of "Pediatric Hydrocephalus" by Guiseppe Cinalli, Wirginia Maixner, Christian Sainte-Rose (editors)
This review summarizes the content and usefulness of this multi-author volume for those involved in the treatment of pediatric hydrocephalus
FAK acts as a suppressor of RTK-MAP kinase signalling in Drosophila melanogaster epithelia and human cancer cells
Receptor Tyrosine Kinases (RTKs) and Focal Adhesion Kinase (FAK) regulate multiple signalling pathways, including mitogen-activated protein (MAP) kinase pathway. FAK interacts with several RTKs but little is known about how FAK regulates their downstream signalling. Here we investigated how FAK regulates signalling resulting from the overexpression of the RTKs RET and EGFR. FAK suppressed RTKs signalling in Drosophila melanogaster epithelia by impairing MAPK pathway. This regulation was also observed in MDA-MB-231 human breast cancer cells, suggesting it is a conserved phenomenon in humans. Mechanistically, FAK reduced receptor recycling into the plasma membrane, which resulted in lower MAPK activation. Conversely, increasing the membrane pool of the receptor increased MAPK pathway signalling. FAK is widely considered as a therapeutic target in cancer biology; however, it also has tumour suppressor properties in some contexts. Therefore, the FAK-mediated negative regulation of RTK/MAPK signalling described here may have potential implications in the designing of therapy strategies for RTK-driven tumours
Recommended from our members
A High-Energy Resolution 4 cm-wide Double-Sided Silicon Strip Detector
Pharmacokinetics of sepantronium bromide (YM155), a small-molecule suppressor of survivin, in Japanese patients with advanced solid tumors: dose proportionality and influence of renal impairment
Recommended from our members
Recent Results From a Si/CdTe Semiconductor Compton Telescope
We are developing a Compton telescope based on high resolution Si and CdTe detectors for astrophysical observations in sub-MeV/MeV gamma-ray region. Recently, we constructed a prototype Compton telescope which consists of six layers of double-sided Si strip detectors and CdTe pixel detectors to demonstrate the basic performance of this new technology. By irradiating the detector with gamma-rays from radio isotope sources, we have succeeded in Compton reconstruction of images and spectra. The obtained angular resolution is 3.9{sup o} (FWHM) at 511 keV, and the energy resolution is 14 keV (FWHM) at the same energy. In addition to the conventional Compton reconstruction, i.e., drawing cones in the sky, we also demonstrated a full reconstruction by tracking Compton recoil electrons using the signals detected in successive Si layers. By irradiating {sup 137}Cs source, we successfully obtained an image and a spectrum of 662 keV line emission with this method. As a next step, development of larger double-sided Si strip detectors with a size of 4 cm x 4 cm is underway to improve the effective area of the Compton telescope. We are also developing a new low-noise analog ASIC to handle the increasing number of channels. Initial results from these two new technologies are presented in this paper as well
Dizajniranje i vrednovanje bioadhezijskog filma za transdermalnu isporuku propranolol hidroklorida
The objective of the study was to develop a suitable transdermal delivery system for propranolol hydrochloride (PPL) via employing chitosan as a film former. Drug concentration uniformity, thickness, moisture uptake capacity and skin bioadhesion of the films were characterized. The effects of chitosan and PPL concentration and different penetration enhancers on the release and permeation profiles from the films were investigated. Skin irritation of the candidate film was evaluated.
Chitosan film (PPL 2 mg cm2, chitosan 2 % m/m, cineol 10 %, m/m) was found non-irritant and achieved 88.2 % release after 8 hours in phosphate buffer. Significant high (p < 0.001) permeation of PPL through rat skin was obtained using this film compared to the film without enhancer (about 8 times enhancement factor), making it a promising transdermal delivery system for PPL.Cilj rada bio je razvoj pogodnog transdermalnog sustava na bazi kitozana za isporuku propranolol hidroklorida (PPL). Svim pripravcima ispitana je jednoliÄnost udjela lijeka, debljina, sposobnost vlaĆŸenja i bioadhezivnost na koĆŸu. Ispitivan je i utjecaj kitozana, koncentracije PPL-a i sredstva za poveÄanje permeacije na oslobaÄanje i permeacijski profil, te potencijalni iritacijski uÄinak na koĆŸu. Iz kitozanskog filma (PPL 2 mg cm2, 2 %, m/m, kitozana i 10 %, m/m, cineola), koji nije djelovao iritabilno, postignuto je 88,2 % oslobaÄanja nakon 8 sati u fosfatnom puferu. S ovim pripravkom postignuta je i vrlo znaÄajna (p < 0,001) permeacija PPL kroz koĆŸu ĆĄtakora, oko osam puta veÄa u usporedbi s filmom bez sredstva za poveÄanje permeacije. Pripravak bi se mogao upotrijebiti za transdermalnu isporuku PPL
Functional Integration of Grafted Neural Stem Cell-Derived Dopaminergic Neurons Monitored by Optogenetics in an In Vitro Parkinson Model
Intrastriatal grafts of stem cell-derived dopamine (DA) neurons induce behavioral recovery in animal models of Parkinson's disease (PD), but how they functionally integrate in host neural circuitries is poorly understood. Here, Wnt5a-overexpressing neural stem cells derived from embryonic ventral mesencephalon of tyrosine hydroxylase-GFP transgenic mice were expanded as neurospheres and transplanted into organotypic cultures of wild type mouse striatum. Differentiated GFP-labeled DA neurons in the grafts exhibited mature neuronal properties, including spontaneous firing of action potentials, presence of post-synaptic currents, and functional expression of DA D2 autoreceptors. These properties resembled those recorded from identical cells in acute slices of intrastriatal grafts in the 6-hydroxy-DA-induced mouse PD model and from DA neurons in intact substantia nigra. Optogenetic activation or inhibition of grafted cells and host neurons using channelrhodopsin-2 (ChR2) and halorhodopsin (NpHR), respectively, revealed complex, bi-directional synaptic interactions between grafted cells and host neurons and extensive synaptic connectivity within the graft. Our data demonstrate for the first time using optogenetics that ectopically grafted stem cell-derived DA neurons become functionally integrated in the DA-denervated striatum. Further optogenetic dissection of the synaptic wiring between grafted and host neurons will be crucial to clarify the cellular and synaptic mechanisms underlying behavioral recovery as well as adverse effects following stem cell-based DA cell replacement strategies in PD
- âŠ