14 research outputs found
LOWER EXTREMITY KINEMATICS OF SKI MOTION ON HILLS
This research study aimed to collect thre- dimensional joint angles of the lower extremity during a basic ski motion in order to provide more quantitative teaching guide-lines for ski instructors. Eleven infrared cameras were placed to cover the capture volume of three different stopping movements (e.g. “Pflug Fahren”) on hills. Six ski instructors participated in the test. Three trials of each stop were selected for comparison. Based on the results, skiers tended to use the edge of the ski and maintain a wider “V” shape at the shortest stop distance (e.g. 2m) compared to the other stops. Also, each skier had to invert the foot with a less flexed and more abducted knee and hip position as the stopping distance was decreased. This information will be useful for the development of more objective teaching guide-lines for beginner skiers
Endotoxin and House Dust Mite Allergen Levels on Synthetic and Buckwheat Pillows
Pillows are known to contain significant levels of indoor allergens and endotoxin, that are of importance to house dust mite sensitized asthmatics. Buckwheat pillows are commonly used in Korea. We studied the levels of the house dust mite allergen, Der f 1, and endotoxin on new synthetic and buckwheat pillows and their accumulation over three months. Endotoxin levels were significantly higher on new buckwheat pillows compared to synthetic pillows; geometric mean levels (95% CI) were 60,950 EU/g (30,270-122,700) and 4,887 EU/g (2,570-9,311) respectively (p<0.001). No Der f 1 was detected on the new pillows. After three months Der f 1 levels were similar on buckwheat and synthetic pillows, geometric mean levels (95% CI) were 1.16 µg/g (0.02-8.13) and 1.08 µg/g (0.19-1.68) respectively. These results indicate that buckwheat pillows are a source of very high endotoxin levels that may be of relevance to asthma severity of atopic asthmatics
Chestnut as a Food Allergen: Identification of Major Allergens
To evaluate the clinical significance of chestnut as a food allergen in Korea, skin prick test and ELISA were done in 1,738 patients with respiratory allergies. To identify the IgE binding components, IgE-immunoblotting, 2D IgE-immunoblotting and MALDI-TOF were performed. To observe the effects of digestive enzymes and a boiling treatment, simulated gastric fluid (SGF) and simulated intestinal fluids (SIF) were incubated with chestnut extracts, and IgE-immunoblotting were then repeated. Skin prick test revealed that 56 (3.2%) patients showed more than 2+ of allergen to histamine ratio to chestnut. Among the 21 IgE binding components, 9 bands were found in more than 50% of the sera tested and the 24 kDa protein had the highest binding intensity. The amino acid sequence of the 24 kDa protein (pI 6.3) had homology with legume protein of oak tree. SGF, SIF and boiling treatment were able to suppress the IgE binding components. In conclusion, chestnut ingestion was shown to induce IgE mediated responses with a 3.2% sensitization rate. Twenty one IgE binding components and one new allergen (the 24 kDa protein) were identified. Digestive enzymes and boiling treatment were able to decrease the allergenic potency
Identification of Chironomus kiiensis allergens, a dominant species of non-biting midges in Korea
Non-biting midges are known to contain potent inhalant allergens. IgE antibody responses to the crude extract of Chironomus kiiensis adults, a dominant chironomid species in Korea, were examined. With the IgE-ELISA or passive cutaneous anaphylaxis reactions, increased levels of chironomid-specific IgE were detected in the skin test positive human sera, or immunized BALB/c mouse sera with the crude extract adsorbed to alum. IgE-immunoblot analysis showed major IgE-reacting protein band patterns, which reacted with more than 50% of the skin test positive human sera, at 110, 80, 73, 46, 40, 37, 34, and 31 kDa. The reactive band patterns were largely similar between skin test positive humans and immune BALB/c mice. However, the bands of 55, 31, 27, 26, 24, and 23 kDa were found only in sensitized humans, but not in immunized mice
Detailed analysis of gyroid structures in diblock copolymer thin films with synchrotron grazing-incidence X-ray scattering
In this study, a grazing-incidence X-ray scattering (GIXS) formula was derived for gyroid structures formed in thin films supported on substrates. Two-dimensional GIXS patterns were measured for gyroid structures formed in polystyrene-b-polyisoprene (PS-b-PI) diblock copolymer nanometre-scale thin films supported on silicon substrates, and a quantitative analysis of the obtained two-dimensional GIXS data was conducted with the scattering formula. This analysis provided details ( lattice parameter, width of the PS phase, positional distortion factor, orientation and orientation distribution) of the gyroid structures developed in the diblock copolymer thin films that are not easily obtained using conventional techniques. Moreover, it was possible to simulate complete and detailed two-dimensional GIXS patterns with the determined structure parameters
Facile Synthesis of SnO2 Aerogel/Reduced Graphene Oxide Nanocomposites via in Situ Annealing for the Photocatalytic Degradation of Methyl Orange
SnO2 aerogel/reduced graphene oxide (rGO) nanocomposites were synthesized using the sol–gel method. A homogeneous dispersion of graphene oxide (GO) flakes in a tin precursor solution was captured in a three-dimensional network SnO2 aerogel matrix and successively underwent supercritical alcohol drying followed by the in situ thermal reduction of GO, resulting in SnO2 aerogel/rGO nanocomposites. The chemical interaction between aerogel matrix and GO functional groups was confirmed by a peak shift in the Fourier transform infrared spectra and a change in the optical bandgap of the diffuse reflectance spectra. The role of rGO in 3D aerogel structure was studied in terms of photocatalytic activity with detailed mechanism of the enhancement such as electron transfer between the GO and SnO2. In addition, the photocatalytic activity of these nanocomposites in the methyl orange degradation varied depending on the amount of rGO loading in the SnO2 aerogel matrix; an appropriate amount of rGO was required for the highest enhancement in the photocatalytic activity of the SnO2 aerogel. The proposed nanocomposites could be a useful solution against water pollutants
Viral latent membrane protein 1 (LMP-1)–induced CD99 down-regulation in B cells leads to the generation of cells with Hodgkin's and Reed-Sternberg phenotype
Recently we reported that the down-regulation of CD99 (Mic2) is a primary requirement for the generation of Hodgkin's and Reed-Sternberg (H-RS) cells seen in Hodgkin's disease. In this study, we provide evidence that the down-regulation of CD99 is induced by high expression of Epstein-Barr virus (EBV) latent membrane protein 1 (LMP-1), which is highly expressed in H-RS cells of EBV-associated Hodgkin's disease. To investigate the effect of LMP-1 on the expression of CD99 in vitro, we established a stable cell line by transfecting an SV40-early promoter driven-LMP-1 expression construct into a neoplastic lymphoblastoid B cell line, IM9, in which the level of endogenous LMP-1 expression is almost negligible. In this cell line, the overexpression of LMP-1 led to the down-regulation of CD99 and the acquisition of morphological and functional characteristics of H-RS cells indistinguishable from those in lymph nodes of Hodgkin's disease patients and in CD99-deficient B cells. In addition, induced LMP-1 expression in an EBV-negative B cell clone, BJAB, directly caused the down-regulation of surface CD99 expression. Northern and Western analysis data, showing that overexpression of LMP-1 negatively influenced the expression of CD99, were supported by experiments in which a CD99 promoter-driven luciferase promoter reporter construct transfected into 293T cells was down-regulated when LMP-1 was coexpressed. Therefore, our data strongly suggest that the EBV LMP-1 protein plays a pivotal role in the down-regulation of CD99 via transcriptional regulation, which leads to the generation of the H-RS cells.Supported by the 99 DiNonA Inc R&D Project, Seoul, Korea. MR was supported by the Leukemia Research Fund, London, UK