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101.
Boyer BB Mohatt GV Plaetke R Herron J Stanhope KL Stephensen C Havel PJ;CANHR Project Team 《Obesity (Silver Spring, Md.)》2007,15(11):2535-2540
Objective: This study investigated the prevalence of metabolic syndrome and its defining components among Yup'ik Eskimos. Research Methods and Procedures: A cross‐sectional study design that included 710 adult Yup'ik Eskimos ≥18 years of age residing in 8 communities in Southwest Alaska. The prevalence of metabolic syndrome was determined using the recently updated Adult Treatment Panel III criteria. Results: The prevalence of metabolic syndrome in this study cohort was 14.7%, and varied by sex with 8.6% of the men and 19.8% of the women having metabolic syndrome. This is lower than the prevalence of 23.9% in the general U.S. adult population. The most common metabolic syndrome components/risk factors were increased waist circumference and elevated blood glucose. High‐density lipoprotein (HDL) cholesterol levels in Yup'ik Eskimos were significantly higher, and triglycerides lower than levels reported in National Health and Nutritional Examination III. Discussion: Compared with other populations, metabolic syndrome is relatively uncommon in Yup'ik Eskimos. The higher prevalence among Yup'ik women is primarily explained by their large waist circumference, suggesting central body fat accumulation. Further increases in metabolic syndrome risk factors among Yup'ik Eskimos could lead to increases in the prevalence of type 2 diabetes and cardiovascular disease, once rare in this population. 相似文献
102.
McTiernan A Sorensen B Irwin ML Morgan A Yasui Y Rudolph RE Surawicz C Lampe JW Lampe PD Ayub K Potter JD 《Obesity (Silver Spring, Md.)》2007,15(6):1496-1512
Objectives: The effect of national exercise recommendations on adiposity is unknown and may differ by sex. We examined long‐term effects of aerobic exercise on adiposity in women and men. Research Methods and Procedures: This was a 12‐month randomized, controlled clinical trial testing exercise effect on weight and body composition in men (N = 102) and women (N = 100). Sedentary/unfit persons, 40 to 75 years old, were recruited through physician practices and media. The intervention was facility‐ and home‐based moderate‐to‐vigorous intensity aerobic activity, 60 min/d, 6 days/wk vs. controls (no intervention). Results: Exercisers exercised a mean 370 min/wk (men) and 295 min/wk (women), and seven dropped the intervention. Exercisers lost weight (women, ?1.4 vs. +0.7 kg in controls, p = 0.008; men, ?1.8 vs. ?0.1 kg in controls, p = 0.03), BMI (women, ?0.6 vs. +0.3 kg/m2 in controls, p = 0.006; men, ?0.5 kg/m2 vs. no change in controls, p = 0.03), waist circumference (women, ?1.4 vs. +2.2 cm in controls, p < 0.001; men, ?3.3 vs. ?0.4 cm in controls, p = 0.003), and total fat mass (women, ?1.9 vs. +0.2 kg in controls, p = 0.001; men, ?3.0 vs. +0.2 kg in controls, p < 0.001). Exercisers with greater increases in pedometer‐measured steps per day had greater decreases in weight, BMI, body fat, and intra‐abdominal fat (all p trend < 0.05 in both men and women). Similar trends were observed for increased minutes per day of exercise and for increases in maximal oxygen consumption. Discussion: These data support the U.S. Department of Agriculture and Institute of Medicine guidelines of 60 min/d of moderate‐to‐vigorous physical activity. 相似文献
103.
104.
Proteome and cytoskeleton responses in osteosarcoma cells with reduced OXPHOS activity 总被引:2,自引:0,他引:2
We have recently shown disorganization of the vimentin network in cultured cells deficient in oxidative phosphorylation (OXPHOS). We describe here the cellular responses to OXPHOS deficiency in osteosarcoma cells upon complex I (CI) and complex IV (CIV) inhibition, and upon the lack of mitochondrial DNA (rho0 cells). We examined the cytoskeletal organization and the distribution of mitochondria and analysed total proteome by 2-DE and vimentin expression by ELISA. Upon CIV inhibition and in rho0 cells, the vimentin network had collapsed around the nucleus and formed thick bundles. The mitochondria formed a perinuclear crescent upon CIV inhibition, whereas they accumulated around the nucleus in the rho0 cells, where the amount of vimentin was increased. Analysis of the total proteome revealed that a lack of mitochondrial DNA or inhibition of CI or CIV led to changes in the expression of cytoskeletal and cytoskeleton-associated proteins and proteins involved in apoptosis, OXPHOS, glycolysis, the tricarboxylic acid cycle, and oxidative stress responses. Our findings suggest that a deficiency in the energy converting system and oxidative stress can lead to cytoskeletal changes. 相似文献
105.
Inhibition of TGF-beta2 with AP 12009 in recurrent malignant gliomas: from preclinical to phase I/II studies 总被引:4,自引:0,他引:4
Hau P Jachimczak P Schlingensiepen R Schulmeyer F Jauch T Steinbrecher A Brawanski A Proescholdt M Schlaier J Buchroithner J Pichler J Wurm G Mehdorn M Strege R Schuierer G Villarrubia V Fellner F Jansen O Straube T Nohria V Goldbrunner M Kunst M Schmaus S Stauder G Bogdahn U Schlingensiepen KH 《Oligonucleotides》2007,17(2):201-212
Transforming growth factor-beta2 (TGF-beta2) is known to suppress the immune response to cancer cells and plays a pivotal role in tumor progression by regulating key mechanisms including proliferation, metastasis, and angiogenesis. For targeted protein suppression the TGF-beta2-specific antisense oligodeoxynucleotide AP 12009 was developed. In vitro experiments have been performed to prove specificity and efficacy of the TGF-beta2 inhibitor AP 12009 employing patient-derived malignant glioma cells as well as peripheral blood mononuclear cells (PBMCs) from patients. Clinically, the antisense compound AP 12009 was assessed in three Phase I/II-studies for the treatment of patients with recurrent or refractory malignant (high-grade) glioma WHO grade III or IV. Although the study was not primarily designed as an efficacy evaluation, prolonged survival compared to literature data and response data were observed, which are very rarely seen in this tumor indication. Two patients experienced long-lasting complete tumor remissions. These results implicate targeted TGF-beta2-suppression using AP 12009 as a promising novel approach for malignant gliomas and other highly aggressive, TGF-beta-2-overexpressing tumors. 相似文献
106.
Monique Cadrin Norma McFarlane-Anderson Mary-Ellen Harper Johanna Gaffield Nicole Bégin-Heick 《Journal of cellular biochemistry》1996,62(3):334-341
The subcellular localization of the heterotrimeric G-proteins in hepatocytes in situ was compared to that in hepatocytes in primary culture. The ability of various ligands to activate adenylyl cyclase (AC) in membrane preparations was also investigated. In hepatocytes in situ the G proteins were mainly localized at the plasma membrane while in hepatocytes in culture they were predominantly cytoplasmic. The localization of the G-proteins in hepatocytes in situ correlates with their role in signal transduction. In homogenates prepared from the cultured cells, ligands which stimulate AC via Gsα were without effect, which was consistent with the localization of Gsα in the cytoplasmic and nuclear compartments. The “relocalization” of the G proteins to the cytoplasm when cells are cultured suggests that transmembrane signalling may be regulated by cell differentiation and cell-cell and cell-extracellular matrix interactions. © 1996 Wiley-Liss, Inc. 相似文献
107.
The Circadian Clock Gene Circuit Controls Protein and Phosphoprotein Rhythms in Arabidopsis thaliana
108.
The distribution of microplankton in the McMurdo Dry Valley Lakes,Antarctica: response to ecosystem legacy or present-day climatic controls? 总被引:3,自引:0,他引:3
Emily?C.?RobertsEmail author John?C.?Priscu Craig?Wolf W.?Berry?Lyons Johanna?Laybourn-Parry 《Polar Biology》2004,27(4):238-249
Plankton abundance and biomass were investigated in five lakes of the McMurdo Dry Valleys, Antarctica: Lakes Bonney, Fryxell, Joyce, Hoare and Miers. Despite plankton communities being dominated by organisms <100 m in length, there were striking differences between the lakes, including large variations in plankton vertical distribution and differences in total plankton biomass. Bacterial biomass was highest in the anoxic monimolimnia of the meromictic lakes, reaching 191 g C l–1 in Lake Fryxell. Photosynthetic nanoflagellates dominated phytoplankton in the five lakes studied. Highest chlorophyll a concentrations were recorded at the chemocline of Lake Fryxell (21 g chl a l–1). Heterotrophic nanoflagellate concentrations were low, ranging from 2 cells ml–1 in Hoare to 237 cells ml–1 in Bonney. By Antarctic standards, ciliates were relatively successful in terms of biomass and diversity in Lakes Fryxell and Hoare. In contrast, Lake Miers possessed extremely low ciliate abundance (<0.04 cells ml–1). On both sampling occasions, copepod nauplii were observed in Lake Joyce. This is the first recording of crustacean zooplankton within the McMurdo Dry Valley Lakes. Because the foodwebs of these lakes are structured by bottom-up forces, differences in plankton distributions could be related to the physicochemical characteristics of each lake. The effect of lake evolution (legacy) and present-day climate change on planktonic dynamics is discussed. 相似文献
109.
110.
Streptococcus alactolyticus is the dominating culturable lactic acid bacterium species in canine jejunum and feces of four fistulated dogs 总被引:2,自引:0,他引:2
Rinkinen ML Koort JM Ouwehand AC Westermarck E Björkroth KJ 《FEMS microbiology letters》2004,230(1):35-39
Canine intestinal lactic acid bacterium (LAB) population in four fistulated dogs was cultured and enumerated using MRS agar. LAB levels ranging from 1.4x10(6) to 1.5x10(7) CFU ml(-1) were obtained in jejunal chyme. In the fecal samples 7.0x10(7) and 2.0x10(8) CFU g(-1) were detected. Thirty randomly selected isolates growing in the highest sample dilutions were identified to species level using numerical analysis of 16S and 23S rDNA restriction fragment length polymorphism patterns (ribotyping) and 16S rDNA sequence analysis. According to these results, Streptococcus alactolyticus was the dominant culturable LAB species in both feces and jejunal chyme. In addition, Lactobacillus murinus and Lactobacillus reuteri were detected. 相似文献