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61.
Protein undernutrition is known to play an important role in the pathogenesis of osteoporotic fracture in elderly. The mechanisms underlying the bone loss in protein undernutrition appeared to be related to an uncoupling between increased bone resorption and bone formation. This was associated with decreased plasma IGF-I levels, with anoestrus and decreased muscle mass. Reversibility of protein undernutrition-induced bone loss was investigated in ovariectomized adult rats, which were fed isocaloric 2.5 % casein diet (OVX2.5) for 16 weeks. Then, the animals were given a supplement of essential amino-acids in similar proportion to that of casein at doses of 2.5% (EAA2.5) or 5% (EAA5) of total food intake for an additional 16 weeks. Essential amino acid supplements increased bone mineral mass and strength in ovariectomized protein-deprived rats. EAA supplements were associated with stimulated bone formation and reduced bone resorption, with increment of plasma IGF-I and of limb muscle mass weight. These results suggest that nutritional intervention with essential amino acid supplements can increase bone mineral mass, bone strength and muscle mass in osteoporotic rats possibly by correcting IGFI status. 相似文献
62.
Jocelyn Glazier 《Anthropology & education quarterly》1998,29(3):379-380
Making Meaning of Whiteness: Exploring Racial Identity with White Teachers. Alice Mclntyre. Albany: State University of New York Press, 1997. 193 pp. 相似文献
63.
Jocelyn Charlton Richard D Williams Mark Weeks Neil J Sebire Sergey Popov Gordan Vujanic William Mifsud Marisa Alcaide-German Lee M Butcher Stephan Beck Kathy Pritchard-Jones 《Genome biology》2014,15(8)
Background
Wilms tumor is the most common pediatric renal malignancy and there is a clinical need for a molecular biomarker to assess treatment response and predict relapse. The known mutated genes in this tumor type show low mutation frequencies, whereas aberrant methylation at 11p15 is by far the most common aberration. We therefore analyzed the epigenome, rather than the genome, to identify ubiquitous tumor-specific biomarkers.Results
Methylome analysis of matched normal kidney and Wilms tumor identifies 309 preliminary methylation variable positions which we translate into three differentially methylated regions (DMRs) for use as tumor-specific biomarkers. Using two novel algorithms we show that these three DMRs are not confounded by cell type composition. We further show that these DMRs are not methylated in embryonic blastema but are intermediately methylated in Wilms tumor precursor lesions. We validate the biomarker DMRs using two independent sample sets of normal kidney and Wilms tumor and seven Wilms tumor histological subtypes, achieving 100% and 98% correct classification, respectively. As proof-of-principle for clinical utility, we successfully use biomarker DMR-2 in a pilot analysis of cell-free circulating DNA to monitor tumor response during treatment in ten patients.Conclusions
These findings define the most common methylated regions in Wilms tumor known to date which are not associated with their embryonic origin or precursor stage. We show that this tumor-specific methylated DNA is released into the blood circulation where it can be detected non-invasively showing potential for clinical utility.Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0434-y) contains supplementary material, which is available to authorized users. 相似文献64.
Culture, Medicine, and Psychiatry - With the United States military stretched thin in the “global war on terror,” military officials have embraced psychopharmaceuticals in the... 相似文献
65.
66.
Wong JC Mitchell RF Striman BL Millar JG Hanks LM 《Journal of economic entomology》2012,105(3):906-915
We evaluated attraction of cerambycid beetle species to blends of known cerambycid pheromones to determine whether such blends could be used as effective trap lures for detecting and monitoring multiple species simultaneously. Pheromone-baited traps captured 1,358 cerambycid beetles of which 1,101 (81.1%) belonged to three species in the subfamily Cerambycinae: Neoclytus acuminatus (F.), Neoclytus mucronatus (F.), and Xylotrechus colonus (F.). Beetles of these species were significantly attracted to synthetic blends that contained their pheromone components (isomers of 3-hydroxy-2-hexanone, 2,3-hexanediol, or both), despite the presence of pheromone components of different species, including other isomers of 2,3-hexanediol, (E/Z)-6,10-dimethyl-5,9-undecadien-2-yl acetate, and citral. In some cases, attraction was partially inhibited by the pheromone components of heterospecific species, whereas for N. acuminatus, attraction was completely inhibited when blends contained (2R*,3S*)-hexanediol, the racemic mixture of diastereomers of its pheromone, (2S,3S)-hexanediol. Among the remaining beetles captured were three species in the subfamily Lamiinae: Astyleiopus variegatus (Haldeman), Graphisurus fasciatus (Degeer), and Lepturges angulatus (LeConte). All three lamiine species were previously known to be attracted to (E/Z)-6,10-dimethyl-5,9-undecadien-2-yl acetate and were captured in significant numbers by blends containing that compound. Our results suggest that different types of cerambycid pheromones can be combined to create effective multispecies lures for use in surveillance programs that target exotic cerambycid species. 相似文献
67.
Tianyi Zhu Xuan Ling Hilary Yong Di Xia Jocelyn Widagdo Victor Anggono 《Journal of molecular biology》2018,430(3):363-371
Genetic polymorphisms in the fat mass and obesity-associated (FTO) gene have been strongly associated with obesity in humans. The cellular level of FTO is tightly regulated, with alterations in its expression influencing energy metabolism, food intake and body weight. Although the proteasome system is involved, the cellular mechanism underlying FTO protein turnover remains unknown. Here, we report that FTO undergoes post-translational ubiquitination on Lys-216. Knock-in HeLa cells harboring the ubiquitin-deficient K216R mutation displayed a slower rate of FTO turnover, resulting in an increase in the level of FTO as well as enhanced phosphorylation of the ribosomal S6 kinase. Surprisingly, we also found that K216R mutation reduced the level of nuclear FTO and completely abolished the nuclear translocation of FTO in response to amino acid starvation. Collectively, our results reveal the functional importance of ubiquitination in controlling FTO expression and localization, which may be crucial for determining body mass and composition. 相似文献
68.
Nicotinamides are ubiquitous cofactors used by many biological systems as redox agents. Stereospecifically labeled cofactors are useful in many studies of nicotinamide-dependent enzymes. Enzyme-directed synthesis of these cofactors is rather common but their stability imposes significant challenges on yield, purity, and preservation. This paper presents the stereospecific synthesis of reduced R- and S-[4-3H] beta-nicotinamide adenine dinucleotide 2' phosphate (NADPH). The method of Valera et al. [Biochem. Biophys. Res. Commun. 148 (1987) 515] was modified to a synthetic procedure that produces both isotopic diastereomers within 2h with an improved yield of 75-90% after purification and lyophilization. In the synthesis, [4-3H]NADP+ was generated as an intermediate (which can be isolated if desired). The specific radioactivities reported here are 2.7 and 1.1 Ci/mmol for the S and R diastereomers, respectively. Specific radioactivities ranging from carrier-free to trace labeling can be achieved with a minor change to the procedure. 相似文献
69.
Yiying Cai Hui Leck Tze Peng Lim Jocelyn Teo Winnie Lee Li Yang Hsu Tse Hsien Koh Thuan Tong Tan Thean-Yen Tan Andrea Lay-Hoon Kwa 《PloS one》2015,10(10)
Background
Current in vitro combination testing methods involve enumeration by bacterial plating, which is labor-intensive and time-consuming. Measurement of bioluminescence, released when bacterial adenosine triphosphate binds to firefly luciferin-luciferase, has been proposed as a surrogate for bacterial counts. We developed an ATP bioluminescent combination testing assay with a rapid turnaround time of 24h to determine effective antibiotic combinations.Methods
100 strains of carbapenem-resistant (CR) GNB [30 Acinetobacter baumannii (AB), 30 Pseudomonas aeruginosa (PA) and 40 Klebsiella pneumoniae (KP)] were used. Bacterial suspensions (105 CFU/ml) were added to 96-well plates containing clinically achievable concentrations of multiple single and two-antibiotic combinations. At 24h, the luminescence intensity of each well was measured. Receiver operator characteristic curves were plotted to determine optimal luminescence threshold (TRLU) to discriminate between inhibitory/non-inhibitory combinations when compared to viable plating. The unweighted accuracy (UA) [(sensitivity + specificity)/2] of TRLU values was determined. External validation was further done using 50 additional CR-GNB.Results
Predictive accuracies of TRLU were high for when all antibiotic combinations and species were collectively analyzed (TRLU = 0.81, UA = 89%). When individual thresholds for each species were determined, UA remained high. Predictive accuracy was highest for KP (TRLU = 0.81, UA = 91%), and lowest for AB (TRLU = 0.83, UA = 87%). Upon external validation, high overall accuracy (91%) was observed. The assay distinguished inhibitory/non-inhibitory combinations with UA of 80%, 94% and 93% for AB, PA and KP respectively.Conclusion
We developed an assay that is robust at identifying useful combinations with a rapid turn-around time of 24h, and may be employed to guide the timely selection of effective antibiotic combinations. 相似文献70.
Xuefei Tan Richland W. Tester Gregory R. Luedtke Sarvajit Chakravarty Babu J. Mavunkel John J. Perumattam Qing Lu Imad Nashashibi Joon Jung Jie Hu Albert Liclican Ramona Almirez Jocelyn Tabora Vinh Tran Maureen Laney Daniel E. Levy Sundeep Dugar 《Bioorganic & medicinal chemistry letters》2010,20(3):828-831
Derivatives of the 4-fluorobenzyl dimethylpiperazine-indole class of p38α MAP kinase inhibitors are described. Biological evaluation of these compounds focused on maintaining activity while improving pharmacokinetic (PK) properties. Improved properties were observed for structures bearing substitutions on the benzylic methylene. 相似文献