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11.
Nu Ri Myeong Hyun Gee Lee Ilyoung Kwack Johnhwan Lee Beom Joon Kim Woo Jun Sul Susun An 《Experimental dermatology》2017,26(9):835-838
We investigate the relationship between scalp microbiota and dandruff/seborrhoeic dermatitis (D/SD), an unpleasant scalp disorder common in human populations. Bacterial and fungal community analyses on scalp of 102 Korean were performed by next‐generation sequencing. Overall scalp microbiome composition significantly differed between normal and disease groups, and especially co‐occurrence network of dominant members was breakdown in disease groups. These findings will provide novel insights into shifts of microbial community relevant to D/SD. 相似文献
12.
In-feed antibiotic effects on the swine intestinal microbiome 总被引:13,自引:0,他引:13
Looft T Johnson TA Allen HK Bayles DO Alt DP Stedtfeld RD Sul WJ Stedtfeld TM Chai B Cole JR Hashsham SA Tiedje JM Stanton TB 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(5):1691-1696
Antibiotics have been administered to agricultural animals for disease treatment, disease prevention, and growth promotion for over 50 y. The impact of such antibiotic use on the treatment of human diseases is hotly debated. We raised pigs in a highly controlled environment, with one portion of the littermates receiving a diet containing performance-enhancing antibiotics [chlortetracycline, sulfamethazine, and penicillin (known as ASP250)] and the other portion receiving the same diet but without the antibiotics. We used phylogenetic, metagenomic, and quantitative PCR-based approaches to address the impact of antibiotics on the swine gut microbiota. Bacterial phylotypes shifted after 14 d of antibiotic treatment, with the medicated pigs showing an increase in Proteobacteria (1-11%) compared with nonmedicated pigs at the same time point. This shift was driven by an increase in Escherichia coli populations. Analysis of the metagenomes showed that microbial functional genes relating to energy production and conversion were increased in the antibiotic-fed pigs. The results also indicate that antibiotic resistance genes increased in abundance and diversity in the medicated swine microbiome despite a high background of resistance genes in nonmedicated swine. Some enriched genes, such as aminoglycoside O-phosphotransferases, confer resistance to antibiotics that were not administered in this study, demonstrating the potential for indirect selection of resistance to classes of antibiotics not fed. The collateral effects of feeding subtherapeutic doses of antibiotics to agricultural animals are apparent and must be considered in cost-benefit analyses. 相似文献
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Macdougall-Shackleton SA Ball GF Edmonds E Sul R Hahn TP 《Brain, behavior and evolution》2005,65(4):262-267
Male Cassin's finches (Carpodacus cassinii) sing long, complex songs that incorporate many elements mimicked from other species. Although one-year-old males (males in their first breeding season) are sexually competent and do breed, they sing a simpler song (fewer syllable types) than do males two or more years old (called after-second-year males). Females do occasionally sing, but with much less stereotypy and complexity than breeding males of any age. We collected brains from free-living breeding after-second-year males (identified by their red plumage), one-year-old males (identified by their female-like brown plumage), and adult females to examine sex- and age-related differences in three song-control nuclei: HVC, Area X and RA. Nuclei volumes were reconstructed by measuring the Nissl-defined area in every second section. There was a large sex difference in all three nuclei, with female volumes 40-50% that of males. There was no difference in HVC volume between age classes of males. However, one-year-old (brown) males had significantly larger Area X volume than did the older (red) males, with red males' Area X about 75% the volume of brown males'. These data raise questions regarding the functional significance of Area X and related nuclei in relation to song development in vocal mimics. 相似文献
16.
Induced adiposity and adipocyte hypertrophy in mice lacking the AMP-activated protein kinase-alpha2 subunit 总被引:4,自引:0,他引:4
AMP-activated protein kinase (AMPK) is considered as a cellular energy sensor that regulates glucose and lipid metabolism by phosphorylating key regulatory enzymes. Despite the major role of adipose tissue in regulating energy partitioning in the organism, the role of AMPK in this tissue has not been addressed. In the present study, we subjected AMPKalpha2 knockout (KO) mice to a high-fat diet to examine the effect of AMPK on adipose tissue formation. Compared with the wild type, AMPKalpha2 KO mice exhibited increased body weight and fat mass. The increase in adipose tissue mass was due to the enlargement of the preexisting adipocytes with increased lipid accumulation. However, we did not observe any changes in adipocyte marker expression, such as peroxisome proliferator-activated receptor-gamma, CCAAT/enhancer-binding protein alpha (C/EBPalpha) and adipocyte fatty acid-binding protein (aFABP/aP2), or total cell number. Unlike impaired glucose homeostasis observed on normal diet feeding, when fed a high-fat diet AMPKalpha2 KO mice did not show differences in glucose tolerance and insulin sensitivity compared with wild-type mice. Our results suggest that the increase in lipid storage in adipose tissue in AMPKalpha2 KO mice may have protected these mice from further impairment of glucose homeostasis that normally accompanies high-fat feeding. Our study also demonstrates that lack of AMPKalpha2 subunit may be a factor contributing to the development of obesity. 相似文献
17.
Hoelscher DM Day RS Lee ES Frankowski RF Kelder SH Ward JL Scheurer ME 《American journal of public health》2004,94(6):1002-1008
OBJECTIVES: We describe results from year 1 of a surveillance system to monitor body mass index in children at the state level. METHODS: A sample of 6630 children attending Texas public schools, weighted to represent 4th, 8th, and 11th grades within race/ethnic subpopulations, was assessed. Body mass index was calculated from measured height and weight; demographic information was obtained from a questionnaire. RESULTS: Prevalence of overweight was 22.4%, 19.2%, and 15.5% for 4th-, 8th-, and 11th-grade students, respectively. Overweight prevalence was highest among Hispanic boys (29.5%-32.6%), fourth-grade Hispanic girls (26.7%), and fourth- and eighth-grade African American girls (30.8% and 23.1%, respectively). Eleventh-grade White/other girls had the lowest prevalence of overweight (5.5%). CONCLUSIONS: These data confirm the increasing prevalence of overweight among US children, especially among Hispanic and African American students compared to White/other students and fourth-grade students relative to 8th- and 11th-grade students. 相似文献
18.
Sul YT 《Biomaterials》2003,24(22):3893-3907
The aim of the present study is to investigate bone tissue reactions to various surface oxide properties, in particular to different surface oxide chemistry of oxidized titanium implants (grade 1). One control and three test screw-shaped implant groups were prepared. Controls were turned implants. Test implants, i.e. S implants, P implants and Ca implants were by the micro-arc oxidation (MAO) method. The surface characterizations were performed with X-ray photoelectron spectroscopy, Auger electron spectroscopy, scanning electron microscopy, X-ray diffractometry and TopScan 3D. Eighty implants were inserted in the femora and tibiae of ten mature New Zealand white rabbits for 6 weeks. The removal torque values (RTQ) showed significant differences between S implants and controls (p=0.022), Ca implants and controls (p=0.0001), Ca implants and P implants (p=0.005) but did not show significant differences between the others (p>0.05). In addition, the bone to metal contact (BMC) around the entire implants demonstrated 186% increase in S implants, 232% increase in P implants and 272% increase in Ca implants when compared to the paired control groups. Based on the comparative analysis of the surface characteristics resulting different bone responses between all groups, it was concluded that surface chemistry and topography separately or together play important roles in the bone response to the oxidized implants. 相似文献
19.
Sul YT Johansson CB Kang Y Jeon DG Albrektsson T 《Clinical implant dentistry and related research》2002,4(2):78-87
Background: The importance of the surface properties of implants for a successful osseointegration has been emphasized. It is generally known that bone response to implant surfaces is considerably related to the various surface properties. Purpose: The purpose of this study was to investigate bone tissue reactions to multifactorial biocompatibility of the surface oxide of electrochemically oxidized titanium implants. The ultimate objective was to improve surface quality, resulting in enhancement of clinical outcomes of osseointegrated implants. Materials and Methods: Three different surface types of commercially pure titanium (c.p. Ti) implants were prepared. Turned implants were used for controls and test implants were prepared by the micro arc oxidation (MAO) method, either in sulphuric acid (S implants) or in phosphoric acid (P implants). Implants were inserted in the femur and tibia of 10 mature New Zealand White rabbits. The bone response was evaluated by biomechanical tests, histology, and histomorphometry. The follow‐up time was 6 weeks. Results: The mean peak values of the removal torque showed significant differences between control and test S implants (p =.022) but showed no significant differences between control and test P implants (p =.195) or between test S and test P implants (p =.457). In addition, the histomorphometric comparisons of the bone‐to‐metal contact around entire implants demonstrated 186% increase in S implants (p =.028) and 232% increase in P implants (p =.028) compared with the paired control groups. Quantification of the bone area in the threads did not show any significant differences. Conclusions: The present results suggest that the primary mode of action in strong bone response to S implants is mechanical interlocking, and to P implants, it is biochemical interaction. It is possible that the phosphate groups in the titanium oxide of P implants provide potential chemical bonding sites for calcium ions and hydroxyapatite of the bone matrix during biologic mineralization. 相似文献
20.
Lee BM Kim HS Kim IS Ahn MY Chun SA Yoo SD Park YA Choi SM Kim KB Han SY Park KL Kwack SJ Song HS Lee KR Bae HJ Cho MH 《Biological & pharmaceutical bulletin》2003,26(5):733-735
Transgene expression and skin tumorigenicity were investigated in transgenic TG-AC mice carrying the v-Ha-ras after treatment with benzo[a]pyrene (BP). Animals treated with 40 microg BP (x2/week/mouse) showed 100% tumor response after 25 weeks, as did 40% of the mice treated with 20 microg BP but 10 microg BP did not produce a tumor response. In the case of animals treated with 40 microg BP for 25 weeks, most of the tumors were proven to be carcinomas (80%, 4 out of 5 mice), and all tumors were shown to be positive in terms of transgene expression detected by in situ hybridization. These data suggest that BP was tumorigenic in a dose-dependent manner in TG-AC mice and that TG-AC mice were dependent on transgene expression during BP carcinogenesis. 相似文献