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101.
Cliona Ni Mhurchu Helen Eyles Chris Schilling Qing Yang William Kaye-Blake Murat Gen? Tony Blakely 《PloS one》2013,8(10)
Background
Targeted food pricing policies may improve population diets. To assess their effects on inequalities, it is important to determine responsiveness to price changes across income levels and ethnic groups.Objective
Our goal was to estimate price elasticity (PE) values for major commonly consumed food groups in New Zealand, by income and ethnicity. PE values represent percentage change in demand associated with 1% change in price of that good (own-PE) or another good (cross-PE).Design
We used food expenditure data from national household economic surveys in 2007/08 and 2009/10 and Food Price Index data from 2007 and 2010. Adopting an Almost Ideal Demand System approach, own-PE and cross-PE estimates were derived for 24 food categories, household income quintiles, and two ethnic groups (Māori and non-Māori).Results
Own-PE estimates (with two exceptions) ranged from −0.44 to −1.78. Cross-PE estimates were generally small; only 31% of absolute values were greater than 0.10. Excluding the outlier ‘energy drinks’, nine of 23 food groups had significantly stronger own-PEs for the lowest versus highest income quintiles (average regression-based difference across food groups −0.30 (95% CI −0.62 to 0.02)). Six own-PEs were significantly stronger among Māori; the average difference for Māori: non-Māori across food groups was −0.26 (95% CI −0.52 to 0.00).Conclusions
Food pricing policies have potential to improve population diets. The greater sensitivity of low-income households and Māori to price changes suggests the beneficial effects of such policies on health would be greatest for these groups. 相似文献102.
Monica Y. Burgos Zepeda Kevin Alessandri Dorothée Murat Chahrazade El Amri Elie Dassa 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(4):755-761
The Uup protein belongs to a subfamily of soluble ATP-binding cassette (ABC) ATPases that have been implicated in several processes different from transmembrane transport of molecules, such as transposon precise excision. We have demonstrated previously that Escherichia coli Uup is able to bind DNA. DNA binding capacity is lowered in a truncated Uup protein lacking its C-terminal domain (CTD), suggesting a contribution of CTD to DNA binding. In the present study, we characterize the role of CTD in the function of Uup, on its overall stability and in DNA binding. To this end, we expressed and purified isolated CTD and we investigated the structural and functional role of this domain. The results underline that CTD is essential for the function of Uup, is stable and able to fold up autonomously. We compared the DNA binding activities of three versions of the protein (Uup, UupΔCTD and CTD) by an electrophoretic mobility shift assay. CTD is able to bind DNA although less efficiently than intact Uup and UupΔCTD. These observations suggest that CTD is an essential domain that contributes directly to the DNA binding ability of Uup. 相似文献
103.
Recombinant human erythropoietin (rhEPO), the prototype erythropoiesis-stimulating agent developed in the 1980s, was among the first recombinant human proteins to be marketed for clinical use in the oncology setting. Anemia is a frequent concern in patients with cancer receiving myelosuppressive chemotherapy and the availability of rhEPO as an alternative to red blood cell transfusions to treat symptomatic anemia created excitement among clinicians, particularly during an era of mounting concern for transfusion-transmissible infections. Early studies of rhEPO for chemotherapy-induced anemia in patients with non-myeloid malignancies showed these agents improved hemoglobin levels and reduced transfusion rates. rhEPO therapy was reported to decrease fatigue and improve quality of life, although the magnitude and clinical meaningfulness of these effects have been debated. More recent clinical trials since 2003 linking rhEPO therapy to increased risk of tumor progression, thrombo-vascular events and mortality prompted implementation of use restrictions to minimize potential for harm. Scientific research to understand the basic mechanisms of the biologic effects of erythropoietin at the cellular receptor and signaling level has revealed pleiotropic cytokine effects extending beyond erythropoiesis regulation. The importance of erythropoietin receptor signaling in normal, non-erythroid tissues and in pre-clinical tumor models has been under intense investigation and scrutiny, as potential mechanisms of the adverse outcomes associated with rhEPO therapy have been debated. Further research will be required to clarify the complex interplay between the diverse hematopoietic and non-hematopoietic effects of erythropoietin in normal and malignant tissues and to optimize the clinical use of rhEPO in the supportive care of cancer patients. 相似文献
104.
β‐Hydroxyamide‐Based Ligands and Their Use in the Enantioselective Borane Reduction of Prochiral Ketones 下载免费PDF全文
Hydroxyamide‐based ligands have occupied a considerable place in asymmetric synthesis. Here we report the synthesis of seven β‐hydroxyamide‐based ligands from the reaction of 2‐hydroxynicotinic acid with chiral amino alcohols and test their effect on the enantioselective reduction of aromatic prochiral ketones with borane in tetrahydofuran (THF). They produce the corresponding secondary alcohols with up to 76% enantiomeric excess (ee) and good to excellent yields (86‐99%). Chirality 26:21–26, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
105.
Phosphofructokinase 2 and glycolysis in HT29 human colon adenocarcinoma cell line. Regulation by insulin and phorbol esters. 下载免费PDF全文
Kinetic properties of phosphofructokinase 2 (PFK2) and regulation of glycolysis by phorbol 12-myristate 13-acetate (PMA) and insulin were investigated in highly glycolytic HT29 colon cancer cells. PFK2 was found to be inhibited by citrate and, to a lesser extent, by phosphoenolpyruvate and ADP, but to be insensitive to inhibition by sn-glycerol phosphate. From these kinetic data, PFK2 from HT29 cells appears different from the liver form, but resembles somewhat the heart isoenzyme. Fructose 2,6-bisphosphate (Fru-2,6-P2) levels, glucose consumption and lactate production are increased in a dose-dependent manner in HT29 cells treated with PMA or insulin. The increase in Fru-2,6-P2 can be related to an increase in the Vmax. of PFK2, persisting after the enzyme has been precipitated with poly(ethylene glycol), without change in the Km for fructose 6-phosphate. The most striking effects of PMA and insulin on Fru-2,6-P2 production are observed after long-term treatment (24 h) and are abolished by actinomycin, cycloheximide and puromycin, suggesting that protein synthesis is involved. Furthermore, the effects of insulin and PMA on glucose consumption, lactate production, Fru-2,6-P2 levels and PFK2 activity are additive, and the effect of insulin on Fru-2,6-P2 production is not altered by pre-treatment of the cells with the phorbol ester. This suggests that these effects are exerted by separate mechanisms. 相似文献
106.
Güzel A Güzel A Günaydin M Alaçam H Saliş O Sükrü Paksu M Murat N Gacar A Güvenç T 《Journal of molecular histology》2012,43(3):351-360
Aspiration is a devastating complication during decontamination procedure in poisoning patients. We have investigated whether S-methylisothiourea protects different pulmonary aspiration gastrointestinal decontamination agent-induced lung injury in rats. Forty-two male Sprague-Dawley rats were assigned to one of six groups (n = 7): normal saline, activated charcoal, polyethylene glycol, normal saline + S-methylisothiourea treated activated charcoal + S-methylisothiourea treated and polyethylene glycol + S-methylisothiourea treated. Normal saline, activated aharcoal and polyethylene glycol were instilled into the lungs. The rats received S-methylisothiourea i.p twice daily for 7 days. Serum surfactant protein D, oxidative stress products and inducible nitric oxide synthase expression in the lung were investigated. The aspiration of activated charcoal significantly increased all histopathological scores (P < 0.01). Only peribronchial inflammatory cell infiltration, alveolar edema, and alveolar histiocytes were increased in the polyethylene glycol groups as compared to the normal saline group (P < 0.05). Pulmonary aspiration increased serum malondialdehyde (P < 0.001), and surfactant protein D (P < 0.05) levels and decreased serum superoxide dismutase levels (P < 0.05). S-methylisothiourea treatment decreased all histopathological scores in the activated charcoal treated S-methylisothiourea group (P < 0.01) and only decreased alveolar edema and alveolar histiocytes in the polyethylene glycol-treated S-methylisothiourea group (P < 0.05). S-methylisothiourea treatment reduced elevated oxidative factors, inducible nitric oxide synthase activity and serum surfactant protein D levels. Our findings showed that S-methylisothiourea may be a protective drug against Activated Charcoal and Polyethylene Glycol-induced lung injury. 相似文献
107.
Two new taxa of Minuartia L. (Caryophyllaceae) from Turkey, Minuartia aksoyi M. Koç & Hamzao?lu sp. nov. and Minuartia buschiana Schischk. subsp. artvinica M. Koç & Hamzao?lu subsp. nov. are described and illustrated. Their taxonomic positions are discussed and they are compared with allied taxa. The distributions of the new and closely related taxa are given. Seed structures were examined by SEM. 相似文献
108.
109.
Murat Ayaz Nizamettin Dalkilic Hulagu Bariskaner Seckin Tuncer Ilhami Demirel 《Biological trace element research》2007,116(3):301-309
Gender differences are related to the manner in which the heart responds to chronic and acute stress conditions of physiological
and pathological nature. Depending on dose, sodium selenite acts as an antioxidant proven to have beneficial effects in several
pathological conditions G. Drasch, J. Schopfer, and G. N. Schrauzer, Selenium/cadmium ratios in human prostates: indicators
of prostate cancer risk of smokers and non-smokers, and relevance to the cancer protective effects of selenium,Biol. Trace Element Res.
103(2), 103–107 (2005); R. G. Kasseroller and G. N. Schrauzer, Treatment of secondary lymphedema of the arm with physical decongestive
therapy and sodium selenite: a review,Am. J. Ther.
7(4), 273–279 (2000); G. N. Schrauzer, Anticarcinogenic effects of selenium,Cell. Mol. Life Sci.
57(13–14), 1864–1873 (2000); I. S. Palmer and O. E. Olson, Relative toxicities of selenite and selenate in the drinking water of rats,J. Nutr.
104(3), 306–314 (1974). To date, little is known about the gender-dependent direct effects of toxic doses of selenite on electrophysiology
of the cardiovascular system H. A. Schroeder and M. Mitchener, Selenium and tellurium in rats: effect on growth, survival
and tumors,J. Nutr.
101(11), 1531–1540 (1971); G. N. Schrauzer, The nutritional significance, metabolism and toxicology of selenomethionine,Adv. Food Nutr. Res.
47, 73–112 (2003). In the present study, the effects of in vitro toxic concentrations of sodium selenite ranging from 10-6 M to 10-3 M were tested on both male and female rat heart preparations. The toxic effects seen in an electrocardiogram and left ventricular
pressure were dose and sex dependent at most of the tested concentrations. The present study clearly shows that at toxic doses,
stress conditions are induced by selenite, resulting in gender-dependent modifications of the heart function. This modification
is more pronounced in the contraction cascade of female rats. Males, on the other hand, had been much more affected in excitation-related
parameters. 相似文献
110.
Gul M Ciragil P Bulbuloglu E Aral M Alkis S Ezberci F 《Acta microbiologica et immunologica Hungarica》2007,54(3):317-321
Comamonas testosteroni is an uncommon isolate in the clinical laboratory as a human pathogen. C. testosteroni most commonly emerges in abdominal pathologies especially in perforated appendicitis. In Turkey we report first time a case of bacteremia due to this organism, in a 22-year-old man with perforated acute appendicitis. The organism was shown to be susceptible to routine antibiotics so it was easily eliminated even after having caused a bacteremia. 相似文献