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Food Biophysics - Caffeic acid phenethyl ester (CAPE) has high cytotoxicity against various cancer cells but has low water solubility and poor bioavailability. The objective of this work was to... 相似文献
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Lab-scale study of an anaerobic membrane bioreactor (AnMBR) for dilute municipal wastewater treatment 总被引:1,自引:0,他引:1
Seung Hyuk Baek Krishna R. Pagilla Hyung-Jin Kim 《Biotechnology and Bioprocess Engineering》2010,15(4):704-708
Anaerobic bioreactors supplemented with membrane technology have become quite popular, owing to their favorable energy recovery
characteristics. In this study, a lab-scale anaerobic Membrane Bioreactor (AnMBR) was assessed in experimental treatments
of pre-settled dilute municipal wastewater obtained from a full-scaled wastewater treatment plant. The MBR system was operated
in continuous flow mode for 440 days. To evaluate the performance of the AnMBR under various loading rates, the hydraulic
retention time (HRT) was reduced in a stepwise manner (from 2 to 0.5 days). Afterward, the mixed liquor suspended solids (MLSS)
were reduced from 7,000 to 3,000 mg/L in increments of 1,000 mg/L, resulting in a decrease in solids retention time (SRT)
at a constant HRT of 1.0 day. The soluble chemical oxygen demand (SCOD) concentration in the feed varied between 38 and 131
mg/L, whereas the average permeate SCOD ranged between 18 and 37 mg/L, reflecting excellent effluent quality. The AnMBR performance
in terms of COD removal proved stable, despite variations in influent characteristics and HRT and SRT changes. The concentration
of extracellular polymeric substance (EPS) was reduced with decreases in HRT from 42 to 22 mg VS/mg of MLSS, thereby indicating
that the increased biomass concentration biodegraded the EPS at lower HRTs. AnMBR is, therefore, demonstrably a feasible option
for the treatment of dilute wastewater with separate stage nitrogen and phosphorus removal processes. 相似文献
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Sena Yoon Eunji Han Young-Chul Choi Honghwan Kee Yongsu Jeong Jaeseung Yoon Kwanghee Baek 《Molecules and cells》2014,37(4):314-321
CDK2 is a key regulator of cell cycle progression. In this study, we screened for miRNAs targeting CDK2 using a luciferase-3′-untranslated region reporter assay. Among 11 hit miRNAs, miR-509-3p reduced CDK2 protein levels and significantly inhibited cancer cell growth. Microarray, Western blotting, and luciferase reporter analyses revealed additional targets of miR-509-3p, including Rac1 and PIK3C2A. Overexpression of miR-509-3p induced G1 cell-cycle arrest and inhibited colony formation and migration. RNAi experiments indicated that the growth-inhibitory effects of miR-509-3p may occur through down-regulation of CDK2, Rac1, and PIK3C2A. Targeting of multiple growth regulatory genes by miR-509-3p may contribute to effective anti-cancer therapy. 相似文献
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Tyrosinase plays a pivotal role in the synthesis of melanin pigment synthesis on skin utilizing tyrosine as a substrate. Melanin is responsible for the protection against harmful ultraviolet irradiation, which can cause significant pathological conditions, such as skin cancers. However, it can also create esthetic problems when accumulated as hyperpigmented spots. Various skin-whitening ingredients which inhibit tyrosinase activity have been identified. Some of them, especially ones with natural product origins, possess phenolic moiety and have been employed in cosmetic products. Semi-synthetic and synthetic inhibitors have also been developed under inspiration of the natural inhibitors yet some of which have no phenolic groups. In this review, tyrosinase inhibitors with natural, semi-synthetic and synthetic origins are listed up with their structures, activities and characteristics. Further, a recent report on the adverse effect of a natural melanin synthesis inhibitor which was included in skin-whitening cosmetics is also briefly discussed. 相似文献
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Min Soo Byun Song E. Kim Jinsick Park Dahyun Yi Young Min Choe Bo Kyung Sohn Hyo Jung Choi Hyewon Baek Ji Young Han Jong Inn Woo Dong Young Lee Alzheimer’s Disease Neuroimaging Initiative 《PloS one》2015,10(11)
We aimed to identify and characterize subtypes of Alzheimer’s disease (AD) exhibiting different patterns of regional brain atrophy on MRI using age- and gender-specific norms of regional brain volumes. AD subjects included in the Alzheimer''s Disease Neuroimaging Initiative study were classified into subtypes based on standardized values (Z-scores) of hippocampal and regional cortical volumes on MRI with reference to age- and gender-specific norms obtained from 222 cognitively normal (CN) subjects. Baseline and longitudinal changes of clinical characteristics over 2 years were compared across subtypes. Whole-brain-level gray matter (GM) atrophy pattern using voxel-based morphometry (VBM) and cerebrospinal fluid (CSF) biomarkers of the subtypes were also investigated. Of 163 AD subjects, 58.9% were classified as the “both impaired” subtype with the typical hippocampal and cortical atrophy pattern, whereas 41.1% were classified as the subtypes with atypical atrophy patterns: “hippocampal atrophy only” (19.0%), “cortical atrophy only” (11.7%), and “both spared” (10.4%). Voxel-based morphometric analysis demonstrated whole-brain-level differences in overall GM atrophy across the subtypes. These subtypes showed different progression rates over 2 years; and all subtypes had significantly lower CSF amyloid-β1–42 levels compared to CN. In conclusion, we identified four AD subtypes exhibiting heterogeneous atrophy patterns on MRI with different progression rates after controlling the effects of aging and gender on atrophy with normative information. CSF biomarker analysis suggests the presence of Aβ neuropathology irrespective of subtypes. Such heterogeneity of MRI-based neuronal injury biomarker and related heterogeneous progression patterns should be considered in clinical trials and practice with AD patients. 相似文献