The effect of cilostazol on hair growth: A type of drug repositioning for the treatment of alopecia with the mechanism of vasodilatation

OAIID:RECH_ACHV_DSTSH_NO:A201703205RECH_ACHV_FG:RR00200003ADJUST_YN:EMP_ID:A079130CITE_RATE:DEPT_NM:의학과EMAIL:[email protected]_YN:CONFIRM:

Current status and characteristics of atopic dermatitis in Korea

Atopic dermatitis (AD) is a very common disease with a prevalence of 15 to 25%, especially in Western countries, and seems to be increasing worldwide and in Korea. The prevalence of AD in Korea is considered to be about 10% in the pediatric population less than 6 years of age and decreases thereafter, falling to about 3% in adults. AD in Korea seems to be a little more common in girls than in boys. Infragluteal eczema, scalp scaling, and periauricular eczema, which are not included in the worldwide diagnostic criteria, are reported to be quite common in Korean AD patients. Recently, the number of adult patients with a more severe form of AD appears to be increasing in Korea. Many Korean patients are more likely to seek treatments that are not proven to be effective scientifically, and patient education is of utmost importance. © Korean Medical Association.N

Nd and Sr isotopes and K-Ar ages of the Ulreungdo alkali volcanic rocks in the East Sea, South Korea

Temporal geochemical and isotopical variations in the Ulreungdo alkali volcanic rocks provide important constraints on the origin and evolution of the volcanic rocks in relation to backarc basin tectonism. We determined the K-Ar ages, major and trace element contents, and Nd and Sr isotopic ratios of the alkali volcanic rocks. The activities of Ulreungdo volcanoes can be divided on the basis of radiometric ages and field occurences, into five stages, though their activities range from 1.4 Ma to 0.01 Ma with short volcanic hiatus (ca. 0.05~0.3 Ma). The Nd-Sr isotopic data for Ulreungdo volcanic rocks enable us to conclude that: (1) the source materials of Ulreungdo volcanics are isotopically heterogeneous in composition, which is explained by the mixing of mantle derived magma and continental crustal source rocks. There is no systematic isotopic variations with eruption stages. Particularly, some volcanic rocks of stage 2 and 3 have extremely wide initial 87Sr/86Sr isotopic variations ranging from 0.7038 to 0.7092, which are influenced by seawater alterations; (2) the Ulreungdo volcanic rocks show EMI characteristics, while volcanic rocks from the Jejudo, Yeong-il and Jeon-gok areas have slightly depleted mantle source characteristics; (3) the trachyandesite of the latest eruption stage was originated from the mantle source materials which differ from other stages. A schematic isotopic evolution model for alkali basaltic magma is presented in the Ulreungdo volcanic island of the backarc basin of Japanese island arc system

Toward establishing precise 40Ar/39Ar chronologies for Late Pleistocene palaeoclimate archives: An example from the Lake Suigetsu (Japan) sedimentary record

The varved Suigetsu (SG06) sediment core is potentially one of the most important and well-constrained mid-latitude palaeoclimate archives, recording continuous deposition during the last ∼150 kyrs. Numerous visible and non-visible volcanic ash layers form unique age markers within SG06. These ash layers are too fine and crystal-poor to be directly dated using the 40Ar/39Ar technique so the tephra were correlated to proximal volcanic deposits using their glass shard compositions. A high-precision 40Ar/39Ar sanidine age of 10.0 ± 0.3 ka (1σ, n = 34, MSWD = 0.71, p = 0.89) was obtained for the SG06-1288 (U-Oki) proximal tephra (Ulleungdo U4). 40Ar/39Ar yields a precision of ±3% near the younger limit of the method, with improved precision possible for older SG06 samples. Such 40Ar/39Ar ages for tephra layers can provide invaluable tie-points within the Lake Suigetsu SG06 sequence, giving independent verification of the core's varve chronology, allowing for the calibration of cosmogenic nuclide production, and providing a precise chronology beyond the varve limit. © 2011 Elsevier Ltd

스트레스 환경에서 ATF3의 전사조절 기전과 그 기능에 관한 연구

Thesis(doctors) --서울대학교 대학원 :약학과(의약생명과학전공),2010.2.Docto

Geochemical and Isotopic Compositions and Geothermometry of Thermal Waters in the Magumsan Area, South Korea

The Magumsan thermal waters of the southeastern Korean Peninsula are pumped out of six deep wells (average depth, 300 m) at temperatures of 30.8-49 degrees C. The thermal waters are chemically classified into two groups: NaHCO3 type (<31 degrees C) and NaCl (HCO3, SO4) type (>40 degrees C), both of which have chemical compositions that are distinct from local groundwater (Ca-HCO3 type). delta O-18 and delta D values suggest that the thermal waters originate from meteoric water and they are isotopically fractionated by silicate hydration or H2S exchange. delta S-34 values (+7.0 to +15%) of dissolved sulfate in the thermal waters reflect enrichment in S-34 through kinetically controlled oxidation of magmatic pyrite in the thermal aquifer and mixing with paleo-seawater. On the He-3/He-4 vs. He-4/Ne-20 diagram, the thermal waters plot along a single air mixing line of dominant crustal He, which indicates that the heat source for the thermal waters is non-volcanogenic thermal energy that is generated from the decay of radioactive elements in crustal rocks. Chalcedony geothermometry and thermodynamic equilibrium calculations using the PHREEQC program indicate a reservoir temperature for the immature thermal waters of 54-86 degrees C and 55-83 degrees C, respectively

Palaeoclimatic and chronostratigraphic interpretations from strontium, carbon and oxygen isotopic ratios in molluscan fossils of Quaternary Seoguipo and Shinyangri Formations, Cheju Island, Korea

Palaeotemperatures and chronostratigraphies of the Quaternary Seoguipo and Shinyangri Formations, Cheju Island, South Korea were investigated in terms of the strontium, oxygen and carbon isotopic compositions of carbonate mollusc shells. The 87Sr/86Sr ratios of mollusc shells from the Seoguipo Formation range from 0.70911 to 0.70914, which yield carbonate ages of 0.5-1.2 Ma (Early to middle Pleistocene) using the linear equation between ages and 87Sr/86Sr ratios of Quaternary seawater. The 87Sr/86Sr ratio (0.70917) of aragonitic shells from the Shinyangri Formation provide late Pleistocene ages (0.04 Ma). Based on AMS 14C dates of mollusc fossil shells from the Shinyangri Formation, the depositional age of the formation has been extended to 1570 yr BP. Palaeotemperatures calculated on the basis of the oxygen isotopic composition of the calcitic mollusc shells from the Seoguipo Formation give a range of values from 12.6 to 19.1 °C, which is lower than the present-day shallow seawater temperature (14.9-25.5 °C) in the vicinity of the Seoguipo coast. Aragonitic mollusc shells from the Shinyangri Formation provide oceanic temperatures ranging from 22.5 to 29.8 °C, which is higher than present-day seawater temperatures (14.1-23.2 °C). The calculated palaeotemperatures of the Seoguipo and Shinyangri Formations are inferred to reflect cold and warm currents flowing over Cheju Island during the Pleistocene to Holocene

Nd and Sr isotopic signatures of mesozoic granitoids in South Korea

Mesozoic granitic plutons in the Korean peninsula have εNd values ranging from -14.9 to +0.4 and initial 87Sr/86Sr ratios from 0.704 to 0.717 ( εSr = -2.5 ∼ 183.7). The Nd and Sr isotopic variations in the granitic rocks are inversely correlated and are clearly divided into two distinct groups namely: a mantle type as in the Mesozoic Kyongsang basin and a crust type as in the Precambrian terranes, based on geologic and geographic differences. Cretaceous granitic rocks in the Kyongsang sedimentary basin have εNd of -4.4 to +0.4 and initial 87Sr/86Sr ratios of 0.704 to 0.706 (εSr = -2.5 ∼ 33.5), indicating derivatives of the mantle source. While, andesitic rocks in the basin have Nd-Sr isotopic compositions (εNd = -12.6 ∼ -0.8, (87Sr/86Sr)i = 0.705 ∼ 0.707, εSr = 9.4 ∼ 38.9) similar with those of the Cretaceous plutonic rocks, implying cogenetic sources of the magma. On the other hand, Jurassic plutons from outside of the basin, including some Cretaceous granites in the Okehon geosynclinal zone, have much lower εNd of -21.0 to -13.6 and higher initial 87Sr/86Sr ratios of 0.711 to 0.717 (εSr = 97.3∼183.7) than the Cretaceous plutons in the Kyongsang basin, which suggests a significant crustal assimilation or contamination of the granitic magma. The two stage model ages of the Cretaceous and Jurassic granite plutons were calculated to be 0.5 to 1.1 Ga and 1.6 to 2.2 Ga, respectively. This data suggests that the source materials of these Mesozoic plutons in the Korean peninsula have evolved considerably since mid - Proterozoic times

Geochemistry and Sr-Nd-Pb isotopic constraints on the petrogenesis of Cenozoic lavas from the Pali Aike and Morro Chico area (52°S), southern Patagonia, South America

Geochemical and isotopic analyses (Sr-Nd-Pb) of late Miocene to Quaternary plateau lavas from the Pali Aike and Morro Chico areas (52°S) were undertaken to constrain the melting processes and mantle sources that contributed to magma generation and the geodynamic evolution of southernmost Patagonia, South America. The Pali Aike and Morro Chico lavas are alkaline (Pali Aike, 45-49wt.% SiO2; 4.3-5.9wt.% Na2O+K2O) and subalkaline (Morro Chico, 50.5-50.8wt.% SiO2; 4.0-4.4wt.% Na2O+K2O), relatively primitive (Pali Aike, 9.5-13.7wt.% MgO; Morro Chico, 7.6-8.8wt.% MgO) mafic volcanic rocks that have typical intraplate ocean island basalt-like signatures. Incompatible trace element ratios and isotopic ratios of the Pali Aike and Morro Chico lavas differ from those of the majority of Neogene southern Patagonian slab window lavas in showing more enriched characteristics and are similar to high-μ (HIMU)-like basalts. The rare earth element (REE) modeling to constrain mantle melting percentages suggests that these lavas were produced by low degrees of partial melting (1.0-2.0% for Pali Aike lavas and about 2.6-2.7% for Morro Chico lavas) of a garnet lherzolite mantle source. The major systematic variations of Sr-Nd-Pb isotopes in southern Patagonian lavas are related to geographic location. The Pali Aike and Morro Chico lavas from the southernmost part of Patagonia have lower 87Sr/86Sr and higher 143Nd/144Nd and 206Pb/204Pb ratios, relative to most of the southern Patagonian lavas erupted north of 49.5°S, pointing to a HIMU-like signature. An isotopically depleted and HIMU-like asthenospheric domain may have been the main source of magmas in the southernmost part of Patagonia (e.g. Pali Aike, Morro Chico, and Camusu Aike volcanic field), suggesting the presence of a major discontinuity in the isotopic composition of the asthenosphere in southern Patagonia. On the basis of geochemical and isotope data and the available geological and geotectonic reconstructions, a link between the HIMU asthenospheric mantle domain beneath southernmost Patagonia and the HIMU mega-province of the southwestern Pacific Ocean is proposed. © 2012 Wiley Publishing Asia Pty Ltd

Evidences of the presence of old continental basement in Cheju volcanic Island, South Korea, revealed by radiometric ages and Nd-Sr isotopes of granitic rocks

Major and trace element and Nd-Sr isotopic data are presented on the granitic rocks known as a basement in the Cheju volcanic island, together with CHIME age data on prophyritic hornblende-biotite granite xenolith from the Byeoldobong area. The CHIME ages from zircon and allanite grains of porphyritic hornblende-biotite granite were determined to be 169 ± 29 Ma and 183 ± 40 Ma, respectively, which are corresponding to a Jurassic age. It is concordant with a K-Ar age of 172.4 ± 5.2 Ma of a biotite granite in the same area, which is comparable to the Daebo granite in the Korean peninsula. Granitic xenoliths from the Byeoldobong area have Nd-Sr isotopic compositions (initial ratio (143Nd/ 144Nd)i = 0.51156∼0.51158, εNd = -19∼-14 and (87Sr/86Sr)i = 0.7156∼0.7164, εSr = 101∼179) which are close to those of Jurassic Daebo granite (εNd = -21∼-14, εSr = 104∼171). On the other hand, the micrographic granite from the drilling core in the Hadeokcheon area gives initial ratio (143Nd/144Nd)i = 0.51218 and (87Sr/86Sr)i = 0.7077), which are comparable to the Cretaceous Bulguksa granite ranging from 0.51184 to 0.51268 in 143Nd/144Nd and 0.7055 to 0.7167 in 87Sr/86Sr. The TNd DM model ages of 1.0 to 1.7 Ga from the Mesozoic granitic plutons in the Cheju island suggest that the source materials of the plutons in the island have evolved since mid-Proterozoic time as those of the peninsula. In combination with the basement geology and petrochemistry, Nd-Sr isotopes, and radiometric and model ages of granitic rocks, our results imply that the Okchon zone is continuously extended to the Cheju volcanic Island of the southeastern end of the continental margin of the Eurasian plate