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141.
142.
Extracellular superoxide dismutase (EC-SOD) is a metalloprotein and functions as an antioxidant enzyme. In this study, we used lentiviral vectors to generate transgenic chickens that express the human EC-SOD gene. The recombinant lentiviruses were injected into the subgerminal cavity of freshly laid eggs. Subsequently, the embryos were incubated to hatch using phases II and III of the surrogate shell ex vivo culture system. Of 158 injected embryos, 16 chicks (G0) hatched and were screened for the hEC-SOD by PCR. Only 1 chick was identified as a transgenic bird containing the transgene in its germline. This founder (G0) bird was mated with wild-type hens to produce transgenic progeny, and 2 transgenic chicks (G1) were produced. In the generated transgenic hens (G2), the hEC-SOD protein was expressed in the egg white and showed antioxidant activity. These results highlight the potential of the chicken for production of biologically active proteins in egg white. [BMB Reports 2013; 46(8): 404-409]  相似文献   
143.
Adhesion molecules such as ICAM-1 are important in the infiltration of leukocytes into the site of inflammation. In this study, we investigated the inhibitory effects of curcumin on ICAM-1 expression and monocyte adhesiveness as well as its underlying action mechanism in the TNF-α-stimulated keratinocytes. Curcumin induced expression of heme oxygenase-1 (HO-1) in the human keratinocyte cell line HaCaT. In addition, curcumin induced Nrf2 activation in dose- and time-dependent manners in the HaCaT cells. Curcumin suppressed TNF-α- induced ICAM-1 expression and subsequent monocyte adhesion, which were reversed by the addition of tin protoporphyrin IX (SnPP), a specific inhibitor of HO-1, or HO-1 knockdown using siRNA. Furthermore, Nrf2 knockdown using siRNA reversed the inhibitory effect of curcumin on the TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that curcumin may exert its anti-inflammatory activity by suppressing the TNF-α-induced ICAM-1 expression and subsequent monocyte adhesion via expression of HO-1 in the keratinocytes. [BMB Reports 2013;46(8): 410-415]  相似文献   
144.
Early menarche is associated with adverse health outcomes, including breast cancer, endometrial cancer, obesity, type 2 diabetes, and cardiovascular disease. Recently, a genomewide association study (GWAS) of age at menarche (AAM) in 104,533 individuals of European ancestry was reported by the ReproGen consortium. They identified 42 loci known and novel loci that were linked to age at menarche. Because age at menarche varies between ethnic groups, we decided to investigate if these results would be replicated in the Korean population. To this end, we examined the association of the SNPs reported in the ReproGen GWAS with AAM in 3,194 individuals from the Korean Genome and Epidemiology Study (KoGES) cohort. Genotype data for total 17 SNPs (6 genotyped SNPs and 11 imputed SNPs) were available for the association analysis using linear regression analysis for age at menarche with controlling current age, waist-to-hip ratio, and body mass index as the covariates. We found replication of the ReproGen study in two SNPs; one SNP (rs466639) in the retinoic acid receptor gamma gene (RXRG), showing a significant association with early menarche (beta = ?0.224 ± 0.065, p value = 5.2 × 10?4, Bonferroni-corrected p value = 0.009), and the other (rs10899489), in GRB2 (growth factor receptor bound protein 2)-associated binding protein 2 (GAB2), linked to late menarche (beta = 0.140 ± 0.047, p value = 2.8 × 10?3, Bonferroni-corrected p value = 0.049). This result possibly suggests that genetic factors governing AAM in the Korean population would be distinct from those in the Europeans, implying roles of modulating or interacting factors in determining AAM, including environmental factors such as nutritional status.  相似文献   
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146.
The butterfly fauna on the Korean peninsula are comprised of both the Palearctic and Oriental species. We hypothesized that the Oriental species (immigrated across the sea) tend to have a wider niche breadth compared with the Palearctic species (immigrated from the continent) since the former migrates long distances across the sea and has to adapt to new environments. We tested this hypothesis using Korean butterfly data on distribution, habitat, food and life history traits. The distribution and ecological traits such as habitat breadth, overwintering stage, and voltinism of the Oriental species were found to be significantly different from the Palearctic species. However, the diet breadth and food plant type were not different. These results partly confirm the peninsula niche breadth hypothesis, which predicted that Oriental species have a broader niche breadth than Palearctic species.  相似文献   
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148.
Microscale cell culture platforms better mimic the in vivo cellular microenvironment than conventional, macroscale systems. Microscale cultures therefore elicit a more authentic response from cultured cells, enabling physiologically realistic in vitro tissue models to be constructed. The fabrication of interconnecting microchambers and microchannels allows drug absorption, distribution, metabolism and elimination to be simulated, and enables precise manipulation of fluid flow to replicate blood circulation. Complex, multi-organ interactions can be investigated using “organ-on-a-chip” toxicology screens. By reproducing the dynamics of multi-organ interaction, the dynamics of various diseases and drug activities can be studied in mechanistic detail. In this review, we summarize the current status of technologies related to pharmacokinetic-based drug toxicity testing, and the use of microtechnology for reproducing the interaction between multiple organs.  相似文献   
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Impaired glucose tolerant (IGT) adults are at elevated risk for cardiovascular disease (CVD). Exercise or metformin reduce CVD risk, but the efficacy of combining treatments is unclear.

Objective:

To determine the effects of exercise training plus metformin (EM), compared with each treatment alone, on CVD risk factors in IGT adults.

Design and Methods:

Subjects were assigned to placebo (P), metformin (M), exercise training plus placebo (EP), or EM (8/group). In a double‐blind design, P or 2,000 mg/d of M were administered for 12 weeks and half performed aerobic and resistance training 3 days/week for ~60 min/day at 70% pretraining heart rate peak. Outcomes included adiposity, blood pressure (BP), lipids, and high sensitivity C‐reactive protein (hs‐CRP). Z‐scores were calculated to determine metabolic syndrome severity.

Results:

M and EM, but not EP, decreased body weight compared with P (P < 0.05). M and EP lowered systolic blood pressure by 6% (P < 0.05), diastolic blood pressure by 6% (P < 0.05), and hs‐CRP by 20% (M: trend P = 0.06; EP: P < 0.05) compared with P. Treatments raised high‐density lipoprotein cholesterol (P < 0.05; EM: trend P = 0.06) compared with P and lowered triacyglycerol (P < 0.05) and metabolic syndrome Z‐score compared with baseline (EP; trend P = 0.07 and EM or M; P < 0.05).

Conclusions:

Although exercise and/or metformin improve some CVD risk factors, only training or metformin alone lowered hs‐CRP and BP. Thus, metformin may attenuate the effects of training on some CVD risk factors and metabolic syndrome severity in IGT adults.  相似文献   
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