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541.
Joong-Sun Kim Kyung-Jin Rhim Won-Seok Jang Sun-Joo Lee Yeonghoon Son Seung-Sook Lee Sunhoo Park Sang Moo Lim 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(1):1-9
In the present study, the detrimental effect of β-emission on pig skin was evaluated. Skin injury was modeled in mini-pigs by exposing the animals to 50 and 100 Gy of β-emission delivered by 166Ho patches. Clinicopathological and immunohistochemical changes in exposed skin were monitored for 18 weeks after β-irradiation. Radiation induced desquamation at 2~4 weeks and gradual repair of this damage was evident 6 weeks after irradiation. Changes in basal cell density and skin depth corresponded to clinically relevant changes. Skin thickness began to decrease 1 week after irradiation, and the skin was thinnest 4 weeks after irradiation. Skin thickness increased transiently during recovery from irradiation-induced skin injury, which was evident 6~8 weeks after irradiation. Epidermal expression of nuclear factor-kappa B (NF-κB) differed significantly between the untreated and irradiated areas. One week after irradiation, cyclooxygenase-2 (COX-2) expression was mostly limited to the basal cell layer and scattered among these cells. High levels of COX-2 expression were detected throughout the full depth of the skin 4 weeks after irradiation. These findings suggest that NF-κB and COX-2 play roles in epidermal cell regeneration following β-irradiation of mini-pig skin. 相似文献
542.
Hye Kyung Baek Hyeji Shim Hyunmook Lim Minju Shim Chul-Kyu Kim Sang-Kyu Park Yong Seok Lee Ki-Duk Song Sung-Jo Kim Sun Shin Yi 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):389-396
Obesity has increased continuously in western countries during the last several decades and recently become a problem in developing countries. Currently, anti-obesity drugs originating from natural products are being investigated for their potential to overcome adverse effects associated with chemical drugs. Artemisinic acid, which was isolated from the well-known anti-malaria herb Artemisia annua (AA) L., was recently shown to possess anti-adipogenic effects in vitro. However, the anti-adipogenic effects of AA in animal models have not yet been investigated. Therefore, we conducted daily oral administration with AA water extract in a diet-induced obesity animal model and treated 3T3-L1 cells with AA to confirm the anti-adipogenic effects in the related protein expressions. We then evaluated the physiology, adipose tissue histology and mRNA expressions of many related genes. Inhibition of adipogenesis by the AA water extract was observed in vitro. In the animal model, weight gain was significantly lower in the AA treated group, but there were no changes in food intake volume or calories. Reductions in lipid droplet size and mRNA expression associated with adipogenesis were also observed in animal epididymal fat. This study is the first to report that AA has an anti-obese effects in vivo. 相似文献
543.
Evaluation of antioxidative activity of extracts from a brown seaweed,Sargassum siliquastrum 总被引:3,自引:0,他引:3
Antioxidative activities of the extracts from Sargassum siliquastrum were determined using the inhibition of red blood cell (RBC) hemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) radicals, suppression of lipid peroxidation using rat brain homogenate, and scavenging activity of superoxide radicals. The dichloromethane fraction isolated from the methanol crude extract by differential solvent extractions exhibited the strongest antioxidant activity in both RBC hemolysis and lipid peroxidation assays. This fraction was further fractionated into four subfractions F1-F4 by silica gel column chromatography. F1 was found to be most effective in protecting RBC against AAPH radicals and in inhibiting lipid peroxidation. On the basis of thin-layer chromatography and UV and IR spectra analyses, all subfractions contained phenolic compounds. However, there was no correlation between the above antioxidant potency and total phenolic compounds estimated by using the Folin-Ciocalteau method. 相似文献
544.
A study was undertaken to determine typical concentrations ofairborne bacteria in a local hospital in the tropicalenvironment of Singapore. Aerial sampling was conducted atvarious locations within the air-conditioned hospital buildingincluding the main lobby, a visitor restricted ward and apharmacy. Concentrations of airborne bacteria exceededavailable local guidelines for indoor air quality (i.e., 500colony forming units m-3 air in an air-conditionedenvironment) in the lobby and pharmacy, but not in the visitorrestricted ward. Results showed that the occupant density wasthe key factor influencing the level of airborne bacteria, buthumidity was also important depending on the particularlocation within the hospital. Bacteria identified wererepresentative of normal microflora of the skin, respiratoryand gastro-intestinal tracts, but also included theopportunistic pathogens Acinetobacter and Flavobacterium spp. 相似文献
545.
Yun Sun Lee Hye Mi Park Nam-Hoon Kim Nomar E. Waminal Yeon Jeong Kim Ki-Byung Lim Jin Hong Baek Hyun Hee Kim Tae-Jin Yang 《Genetic Resources and Crop Evolution》2016,63(2):235-242
Aloe species, which have been used as medicinal plants, belong to the Asphodelaceae family consisting of 530 species. In this study, genetic diversity and phylogenetic relationships among 40 Aloe species including a putative interspecies hybrid were analyzed using PCR band profiles from eight chloroplast intergenic space markers and nucleotide sequence diversity in the psbK–psbI intergenic region. A phylogenetic tree based on psbK–psbI sequences supported the revised classification of the genus Aloe as polyphyletic with several species be re-allocated into three genera Kumara, Aloidendron, and Aloiampelos. Further, the origin of the putative interspecies Aloe hybrid was characterized through molecular cytogenetics. Fluorescence and genomic insitu hybridization illustrated that the hybrid has a bimodal karyotype with a chromosome complement of 2n = 14, of which complementary halves were derived from two parental species, A. vera and A. arborescens. These findings revealed that the hybrid species was allodiploid. The phylogenetic analysis showed that A. arborescens was the maternal genome donor of the hybrid, as both have identical chloroplast genome sequences. We thus conclude that the allodiploid hybrid should be called A. arborescens × A.vera. 相似文献
546.
547.
This study was conducted to understand the effect of N supply in autumn on its uptake and distribution in tree parts and the utilization of reserve N the following year in persimmon trees (Diospyros kaki cv. Fuyu). The treated trees received 22.5-g N each for two successive years as a 3.5% urea solution from September 18 at 5-day intervals. Trees absorbed about 30% on average of the N applied in autumn. Sixty four to 83% of the N absorbed in autumn was in perennial parts, and 65–72% of that was in roots. Total N in perennial parts of the tree fertilized with N increased by over 4.28 g while leaf N changed little during senescence, indicating that the reserve N was constituted mostly by the N absorbed in autumn. Total N in the new growth was about the same as the amount of N declined in spring from perennial parts, indicating that there was little contribution by soil N to sustain new growth. Total dry weights of new growth the following year in a with-N tree were greater by over 34 g than those in a without-N tree. 相似文献
548.
Hyung-Ju Lim Joon Soo An Eun Seo Bae Eunji Cho Sunghoon Hwang Sang-Jip Nam Ki-Bong Oh Sang Kook Lee Dong-Chan Oh 《Marine drugs》2022,20(2)
Streptomyces sp. GET02.ST and Achromobacter sp. GET02.AC were isolated together from the gut of the wharf roach, Ligia exotica, inhabiting the intertidal zone of the west coast of Korea. The co-cultivation of these two strains significantly induced the production of two new metabolites, ligiamycins A (1) and B (2), which were barely detected in the single culture of Streptomyces sp. GET02.ST. The planar structures of ligiamycins A (1) and B (2) were elucidated as new decalins coupled with amino-maleimides by the analysis of various spectroscopic data, including nuclear magnetic resonance (NMR), ultraviolet (UV), and mass (MS) data. The assignment of two nitrogen atoms in amino-maleimide in 1 was accomplished based on 1H-15N heteroatom single quantum coherence spectroscopy (HSQC) NMR experiments. The relative configurations of the ligiamycins were determined using rotating frame Overhauser effect spectroscopy (ROESY) NMR data, and their absolute configurations were deduced by comparing their experimental and calculated optical rotations. Ligiamycin A (1) displayed antibacterial effects against Staphylococcus aureus and Salmonella enterica, while ligiamycin B (2) exhibited mild cell cytotoxicity against human colorectal cancer cells. 相似文献
549.
550.
Hye Lim Jang 《Journal Of Aquatic Food Product Technology》2017,26(2):234-244
In the present study, a peptide showing anti-inflammatory activity was isolated from Arctoscopus (A.) japonicus sandfish protein hydrolysate by hydrolysis and analyzed using ultrafiltration (UF), prep-high-performance liquid chromatography (HPLC), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Effects of heat, pH, salt, and intestinal proteases on stability of the isolated anti-inflammatory peptide were determined. The nitric oxide (NO) scavenging activities of the peptide from meat and roe hydrolysates were 18.43 ± 3.21% and 52.35 ± 8.85%, respectively, at a concentration of 0.1 mg/mL. The anti-inflammatory peptide maintained a similar level of NO scavenging activity to the control in the presence of salt, whereas it showed no resistance to heat, pH, and intestinal proteases. These results suggest that the anti-inflammatory peptide derived from A. japonicus could be used for producing functional foods, protein supplements, and pharmaceutical agents. However, it is necessary to find methods for protection against heat, pH, and proteolysis. 相似文献