We studied the quantum dot-liposome complex (QLC), which is the giant unilamellar vesicle with quantum dots (QDs) incorporated in its lipid bilayer. A spin coating method in conjunction with the electroformation techn...We studied the quantum dot-liposome complex (QLC), which is the giant unilamellar vesicle with quantum dots (QDs) incorporated in its lipid bilayer. A spin coating method in conjunction with the electroformation technique yielded vesicles with highly homogeneous unilamellar structure. We observed QD size dependence of the QLC formation: QLCs form with blue, green and yellow-emission QD (core radius ~1.05 nm, 1.25 nm and 1.65 nm) but not with red-emission QD (core radius ~2.5 nm). In order to explain this size dependence, we made a simple model explaining the QD size effect on QLC formation in terms of the molecular packing parameter and the lipid conformational change. This model predicts that QDs below a certain critical size (radius ≈ 1.8 nm) can stably reside in a lipid bilayer of 4 - 5 nm in thickness for Egg-PC lipids. This is consistent with our previous experimental results. In the case of red-emission QD, QD-aggregations are only observed on the fluorescent microscopy instead of QLC. We expected that the reduction of packing parameter (P) would lead to the change of specific QD radius. This prediction could be verified by our experimental observation of the shift of the specific QD size by mixing DOPG.展开更多
AIM: To examine the association between circulating 25-hydroxyvitamin D [25(OH)D] levels and colorectal adenoma in a case-control study and a meta-analysis. METHODS: We conducted a matched case-control study(112 cases...AIM: To examine the association between circulating 25-hydroxyvitamin D [25(OH)D] levels and colorectal adenoma in a case-control study and a meta-analysis. METHODS: We conducted a matched case-control study(112 cases and 112 matched controls) and combined 15 studies, including our study, in a metaanalysis. The study-specific odds ratios(ORs) and 95% confidence intervals(CIs) were pooled using a randomeffects model. In total, 5454 colorectal adenomas and 6656 controls were included in the meta-analysis. RESULTS: In a meta-analysis including 14 previous studies and our study, we observed a significant inverse association between circulating 25(OH)D levels and colorectal adenoma(OR = 0.68; 95%CI: 0.54-0.82) when comparing the highest category with the lowest category. Stratification by adenoma location(proximal or distal adenoma) showed similar estimates. When we stratified by study region, the ORs(95%CIs) were 0.70(0.52-0.88) in the US and 0.66(0.34-0.97) in Asia. CONCLUSION: These data suggest an inverse association between circulating 25(OH) Dlevels and colorectal adenoma in both Western and Asian populations.展开更多
文摘We studied the quantum dot-liposome complex (QLC), which is the giant unilamellar vesicle with quantum dots (QDs) incorporated in its lipid bilayer. A spin coating method in conjunction with the electroformation technique yielded vesicles with highly homogeneous unilamellar structure. We observed QD size dependence of the QLC formation: QLCs form with blue, green and yellow-emission QD (core radius ~1.05 nm, 1.25 nm and 1.65 nm) but not with red-emission QD (core radius ~2.5 nm). In order to explain this size dependence, we made a simple model explaining the QD size effect on QLC formation in terms of the molecular packing parameter and the lipid conformational change. This model predicts that QDs below a certain critical size (radius ≈ 1.8 nm) can stably reside in a lipid bilayer of 4 - 5 nm in thickness for Egg-PC lipids. This is consistent with our previous experimental results. In the case of red-emission QD, QD-aggregations are only observed on the fluorescent microscopy instead of QLC. We expected that the reduction of packing parameter (P) would lead to the change of specific QD radius. This prediction could be verified by our experimental observation of the shift of the specific QD size by mixing DOPG.
基金Supported by Grants from Basic Science Research Program through the National Research Foundation of Korea,which is funded by the Korean Government,No.NRF-2011-0011028the Sookmyung Women’s University Research Grants,No.1-1503-0168
文摘AIM: To examine the association between circulating 25-hydroxyvitamin D [25(OH)D] levels and colorectal adenoma in a case-control study and a meta-analysis. METHODS: We conducted a matched case-control study(112 cases and 112 matched controls) and combined 15 studies, including our study, in a metaanalysis. The study-specific odds ratios(ORs) and 95% confidence intervals(CIs) were pooled using a randomeffects model. In total, 5454 colorectal adenomas and 6656 controls were included in the meta-analysis. RESULTS: In a meta-analysis including 14 previous studies and our study, we observed a significant inverse association between circulating 25(OH)D levels and colorectal adenoma(OR = 0.68; 95%CI: 0.54-0.82) when comparing the highest category with the lowest category. Stratification by adenoma location(proximal or distal adenoma) showed similar estimates. When we stratified by study region, the ORs(95%CIs) were 0.70(0.52-0.88) in the US and 0.66(0.34-0.97) in Asia. CONCLUSION: These data suggest an inverse association between circulating 25(OH) Dlevels and colorectal adenoma in both Western and Asian populations.
