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21.
Protein transduction domains (PTDs) have been shown to promote the delivery of therapeutic proteins or peptides into the living cells. In a previous study, we showed that the double mutant of TCTP-PTD 13, TCTP-PTD 13M2, was more effective in the delivery of insulin than the wild-type TCTP-PTD 13. In this study, we applied this approach to the nasal delivery of a different peptide, exendin-4, using as carriers, several modified TCTP-PTDs, such as TCTP-PTD 13M1, 13M2, and 13M3. Nasal co-administration of TCTP-PTD 13M2 with exendin-4 showed the highest exendin-4 uptake among the three analogs in normal rats, and also decreased blood glucose levels by 43.3% compared with that of exendin-4 alone and by 18.6% compared with that of exendin-4 plus TCTP-PTD 13 in diabetic mice. We also designed an additional covalently linked conjugate of TCTP-PTD 13M2 and exendin-4 and evaluated its hypoglycemic effect after subcutaneous or intranasal delivery. Subcutaneous administration of exendin-4 that its C-terminus is covalently linked to TCTP-PTD 13M2 showed hypoglycemic effect of 42.2% compared to that in untreated group, whereas intranasal delivery was not successful in diabetic mice. We conclude that a simple mixing TCTP-PTD 13M2 with peptide/protein drugs can be potentially a generally applicable approach for intranasal delivery into animals. 相似文献
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Anh Bui Thi Kim Minh Nguyen Ngoc Ha Nguyen Thi Hoang Kim Dang Dinh Kien Nguyen Trung Trung Nguyen Quang Cuong Tran Thien Danh Luu Thai 《Bulletin of environmental contamination and toxicology》2018,100(5):720-726
Bulletin of Environmental Contamination and Toxicology - In field survey, Pteris vittata and Pityrogramma calomelanos were only found in arsenic (As) contaminated areas with soil pH 7.2–8.8... 相似文献
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Margaret Raber To Nhu Huynh Karla Crawford Stephanie Kim Joya Chandra 《Journal of community health》2018,43(5):882-885
Comprehensive cancer centers are an important community resource for cancer prevention education in their catchment areas. Colorectal cancer remains one of the most commonly diagnosed cancers in the United States, making prevention a priority. Colorectal cancer prevention targets include lifestyle modifications that are influenced by cultural norms, such as diet change, physical activity and screening behavior. Cancer centers must tailor prevention efforts to multiethnic catchment areas. This paper describes the development and feasibility of a comprehensive cancer center’s approach to community-based colorectal cancer prevention in Houston, Texas, specifically targeting Hispanic and Asian populations. Sites were recruited through a city-wide network of partnerships between the community relations department in the hospital and community organizations. The program consisted of three workshop-style classes per community site. Each class had a similar overall structure, but cultural and site-specific adaptations were made for each group. A total of 33 classes were taught at nine distinct community sites to 1054 participants over 9 months. This program structure may be adapted for the future dissemination of other cancer prevention tools to communities in the area. 相似文献
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Youngwon Kim Tom White Katrien Wijndaele Kate Westgate Stephen J. Sharp Jørn W. Helge Nick J. Wareham Soren Brage 《European journal of epidemiology》2018,33(10):953-964
Little is known about the combined associations of cardiorespiratory fitness (CRF) and hand grip strength (GS) with mortality in general adult populations. The purpose of this study was to compare the relative risk of mortality for CRF, GS, and their combination. In UK Biobank, a prospective cohort of >?0.5 million adults aged 40–69 years, CRF was measured through submaximal bike tests; GS was measured using a hand-dynamometer. This analysis is based on data from 70,913 men and women (832 all-cause, 177 cardiovascular and 503 cancer deaths over 5.7-year follow-up) who provided valid CRF and GS data, and with no history of heart attack/stroke/cancer at baseline. Compared with the lowest CRF category, the hazard ratio (HR) for all-cause mortality was 0.76 [95% confidence interval (CI) 0.64–0.89] and 0.65 (95% CI 0.55–0.78) for the middle and highest CRF categories, respectively, after adjustment for confounders and GS. The highest GS category had an HR of 0.79 (95% CI 0.66–0.95) for all-cause mortality compared with the lowest, after adjustment for confounders and CRF. Similar results were found for cardiovascular and cancer mortality. The HRs for the combination of highest CRF and GS were 0.53 (95% CI 0.39–0.72) for all-cause mortality and 0.31 (95% CI 0.14–0.67) for cardiovascular mortality, compared with the reference category of lowest CRF and GS: no significant association for cancer mortality (HR 0.70; 95% CI 0.48–1.02). CRF and GS are both independent predictors of mortality. Improving both CRF and muscle strength, as opposed to either of the two alone, may be the most effective behavioral strategy to reduce all-cause and cardiovascular mortality risk. 相似文献
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Vitchan Kim Sora Yeom Yejin Lee Hyoung-Goo Park Myung-A Cho Harim Kim 《Journal of toxicology and environmental health. Part A》2018,81(12):493-501
Humans possess three cytochrome P450 enzymes in the 2A subfamily (2A6, 2A7, and 2A13). P450 2A13 is mainly expressed in the human trachea and lung, whereas P450 2A6 is found in human liver. The P450 2A13 enzyme may be considered as the primary enzyme responsible for metabolic activation of many tobacco-specific carcinogens. Genetic variations significantly influence the toxicological consequences attributed to tobacco smoking. The aim of this study was to examine the in vitro functional activities of five P450 2A13 genetic variations (R257C, 133_134insT, R101Q, I331T, and R257C/I331T) in P450 2A13*2, *3, *4, and *10 alleles. Mutant clones were constructed and their recombinant enzymes were expressed in Escherichia coli. P450 2A13 mutants containing R257C, 133_134insT, I331T, and R257C/I331T displayed P450 holoenzyme spectra. The R101Q mutant was not apparently expressed. P450 2A13 enzymes displayed the typical type I binding spectra to coumarin and the calculated binding affinities of R257C, R257C/I331T, and 133_134insT mutants were decreased approximately three- to sevenfold. In catalytic analyses of purified mutant enzymes for coumarin and nicotine, the R257C and I331T mutants exhibited lower kcat values with catalytic efficiencies reduced up to approximately 20%. The double mutation of R257C/I331T induced increased Km values and diminished kcat values that resulted in >50% decrease in catalytic efficiencies. For 133_134insT mutant, catalytic activities were not markedly saturated but the measured rates at the highest concentrations were significantly lower than those of the wild-type or other mutant enzymes. Functional analysis of these variations in P450 2A13 allelic variants may help to understand the consequences of P450 2A13 polymorphism in bioactivation of many tobacco-derived carcinogens. 相似文献
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Yoo Yeon Kim Janet Ren Chao Chulho Kim Harry Jung Boyoung Kim Tae-Cheon Kang Jiwon Chang Hae Sang Park Jun-Gyo Suh Jun Ho Lee 《Anatomical record (Hoboken, N.J. : 2007)》2019,302(11):2049-2061
We provide images of the entire central nervous system vasculature, and compare the anatomical findings in six different laboratory animals. A detailed understanding of the specific anatomy for each is important in the design of experimental modeling and for understanding the specific function of each target organ . Six different types of animals, the Korean wild mouse, C57BL/6J mouse, F344 rat, mongolian gerbil, Syrian hamsters, and guinea pigs, were included. To stain the blood vessels in each of the animals, Alcian blue reagent was used to perfuse each species. The bifurcation and anastomotic patterns of the anterior cerebral arteries differed in each species. The vascular supply to the olfactory nerve was visualized as a single artery supplying both olfactory nerves, and arteries supplying the lateral portion of the olfactory nerves originating from the olfactory bulb area. The posterior communicating arteries of the six animals demonstrated unique morphologies. The shape of the hypophyseal portal system varied by species. Most animals used in this study had a hexagonal Circle of Willis, except for the Korean wild mouse. Using this approach, we successfully mapped the brain vascular system in six different species of animals. This information and the images created can guide other researchers as they design research studies and create experimental models for new surgical procedures and approaches. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc. Anat Rec, 302:2049–2061, 2019. © 2019 American Association for Anatomy 相似文献
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