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171.
Helen E MacLean W S Maria Chiu Cathy Ma Julie F McManus Rachel A Davey Rhoda Cameron Amanda J Notini Jeffrey D Zajac 《Physiological genomics》2008,33(1):133-137
We previously generated a conditional floxed mouse line to study androgen action, in which exon 3 of the androgen receptor (AR) gene is flanked by loxP sites, with the neomycin resistance gene present in intron 3. Deletion of exon 3 in global AR knockout mice causes androgen insensitivity syndrome, characterized by genotypic males lacking normal masculinization. We now report that male mice carrying the floxed allele (AR(lox)) have the reverse phenotype, termed hyperandrogenization. AR(lox) mice have increased mass of androgen-dependent tissues, including kidney, (P < 0.001), seminal vesicle (P < 0.001), levator ani muscle (P = 0.001), and heart (P < 0.05). Serum testosterone is not significantly different. Testis mass is normal, histology shows normal spermatogenesis, and AR(lox) males are fertile. AR(lox) males also have normal AR mRNA levels in kidney, brain, levator ani, liver, and testis. This study reaffirms the need to investigate the potential phenotypic effects of floxed alleles in the absence of cre in tissue-specific knockout studies. In addition, this androgen hypersensitivity model may be useful to further investigate the effects of subtle perturbations of androgen action in a range of androgen-responsive systems in the male. 相似文献
172.
The acyclic CB1R inverse agonist taranabant mediates weight loss by increasing energy expenditure and decreasing caloric intake 总被引:6,自引:0,他引:6
Addy C Wright H Van Laere K Gantz I Erondu N Musser BJ Lu K Yuan J Sanabria-Bohórquez SM Stoch A Stevens C Fong TM De Lepeleire I Cilissen C Cote J Rosko K Gendrano IN Nguyen AM Gumbiner B Rothenberg P de Hoon J Bormans G Depré M Eng WS Ravussin E Klein S Blundell J Herman GA Burns HD Hargreaves RJ Wagner J Gottesdiener K Amatruda JM Heymsfield SB 《Cell metabolism》2008,7(1):68-78
Cannabinoid 1 receptor (CB1R) inverse agonists are emerging as a potential obesity therapy. However, the physiological mechanisms by which these agents modulate human energy balance are incompletely elucidated. Here, we describe a comprehensive clinical research study of taranabant, a structurally novel acyclic CB1R inverse agonist. Positron emission tomography imaging using the selective CB1R tracer [(18)F]MK-9470 confirmed central nervous system receptor occupancy levels ( approximately 10%-40%) associated with energy balance/weight-loss effects in animals. In a 12-week weight-loss study, taranabant induced statistically significant weight loss compared to placebo in obese subjects over the entire range of evaluated doses (0.5, 2, 4, and 6 mg once per day) (p < 0.001). Taranabant treatment was associated with dose-related increased incidence of clinical adverse events, including mild to moderate gastrointestinal and psychiatric effects. Mechanism-of-action studies suggest that engagement of the CB1R by taranabant leads to weight loss by reducing food intake and increasing energy expenditure and fat oxidation. 相似文献
173.
Hegedus DD Li R Buchwaldt L Parkin I Whitwill S Coutu C Bekkaoui D Rimmer SR 《Planta》2008,228(2):241-253
Most plants encode a limited set of polygalacturonase inhibitor (PGIP) genes that may be involved in aspects of plant development, but more importantly in the inactivation of polygalacturonases (PG) secreted by pathogens. Previously, we characterized two Brassica napus PGIP genes, BnPgip1 and BnPgip2, which were differentially expressed in response to pathogen infection and wounding. Here we report that the B. napus genome encodes a set of at least 16 PGIP genes that are similar to BnPgip1 or BnPgip2. This is the largest Pgip gene family reported to date. Comparison of the BnPGIPs revealed several sites within the xxLxLxx region of leucine rich repeats that form beta-sheets along the interacting face of the PGIP that are hypervariable and represent good candidates for generating PGIP diversity. Characterization of the regulatory regions and RT-PCR studies with gene-specific primers revealed that individual genes were differentially responsive to pathogen infection, mechanical wounding and signaling molecules. Many of the BnPgip genes responded to infection by the necrotic pathogen, Sclerotinia sclerotiorum; however, these genes were also induced either by jasmonic acid, wounding and salicylic acid or some combination thereof. The large number of PGIPs and the differential manner in which they are regulated likely ensures that B. napus can respond to attack from a broad spectrum of pathogens and pests. 相似文献
174.
175.
Shirley S. Wang Thomas A. Wadden Leslie G. Womble Cathy A. Nonas 《Obesity (Silver Spring, Md.)》2003,11(1):48-53
Objective: In 1999, the Partnership for Healthy Weight Management recommended that providers of commercial weight‐loss programs (and products) voluntarily disclose information concerning the safety, costs, and central components of their programs, as well as the credentials of program staff. These guidelines were drafted without the benefit of data from consumers concerning the specific information they desired. The present study provides such data. Research Methods and Procedures: Participants were 90 women with a mean age of 44.02 ± 9.17 years and body mass index of 36.11 ± 4.82 kg/m2 who were participants in one of two randomized weight‐control trials. Before treatment, respondents were asked to imagine that they were “looking for a weight‐loss plan” and to rate how important each of 16 factors would be in helping them select a plan. Ratings were made using 5‐point scales, anchored by “not at all important” and “extremely important,” (scored 1 and 5, respectively). Participants also identified the five factors that they thought were the most important, as well as the single most important. Results: The mean rating for the importance of safety (4.57 ± 0.60) was significantly greater than that for each of the 15 other variables (all p values < 0.05). In addition, significantly more respondents (27.8%) selected safety as the single most important factor than any other variable (all p values < 0.05). Other factors that were consistently judged as very important included information about diet (4.38 ± 0.68), behavior modification (4.32 ± 0.76), cost (4.19 ± 0.92), and maintenance of weight loss (4.15 ± 0.91). Staff credentials (3.88 ± 0.83) were among the lowest rated items. Discussion: The results generally support the disclosure guidelines proposed by the Partnership for Health Weight Management. Consumers, however, seem to desire information about weight loss, in addition to that concerning safety, cost, and central program components. 相似文献
176.
Martyn Kelly Cathy Bennett Michel Coste Cristina Delgado François Delmas Luc Denys Luc Ector Claude Fauville Martial Ferréol Malgorzata Golub Amelie Jarlman Maria Kahlert John Lucey Bernadette Ní Chatháin Isabel Pardo Peter Pfister Joanna Picinska-Faltynowicz Juliette Rosebery Christine Schranz Jochen Schaumburg Herman van Dam Sirje Vilbaste 《Hydrobiologia》2009,621(1):169-182
The European Union (EU)’s Water Framework Directive (WFD) requires that all Member States participate in intercalibration
exercises in order to ensure that ecological status concepts and assessment levels are consistent across the EU. This paper
describes one such exercise, performed by the countries in the Central/Baltic Geographical Intercalibration Group stretching
from Ireland in the west to Estonia in the east and from the southern parts of Scandinavia to the northern regions of Spain
and Italy (but excluding alpine regions, which were intercalibrated separately). In this exercise, methods used to measure
ecological status of rivers using benthic diatoms were compared. Ecological status is estimated as the ratio between the observed
value of a biological element and the value expected in the absence of significant human impact. Approaches to defining the
‘reference sites’, from which these ‘expected’ values were derived, varied from country to country. Minimum criteria were
established as part of the exercise but there was still considerable variation between national reference values, reflecting
typological differences that could not be resolved during the exercise. A simple multimetric index was developed to compare
boundary values using two widely used diatom metrics. Boundary values for high/good status and good/moderate status set by
each participant were converted to their equivalent values of this intercalibration metric using linear regression. Variation
of ±0.05 EQR units around the median value was considered to be acceptable and the exercise provided a means for those Member
States who fell significantly above or below this line to review their approaches and, if necessary, adjust their boundaries.
Handling editor: J. Padisak 相似文献
177.
178.
Danièle Giblot-Ducray Alireza Marefat Michael R. Gillings Neil M. Parkinson John P. Bowman Kathy Ophel-Keller Cathy Taylor Evelina Facelli Eileen S. Scott 《Systematic and applied microbiology》2009
Strains of Xanthomonas translucens have caused dieback in the Australian pistachio industry for the last 15 years. Such pathogenicity to a dicotyledonous woody host contrasts with that of other pathovars of X. translucens, which are characterized by their pathogenicity to monocotyledonous plant families. Further investigations, using DNA-DNA hybridization, gyrB gene sequencing and integron screening, were conducted to confirm the taxonomic status of the X. translucens pathogenic to pistachio. DNA-DNA hybridization provided a clear classification, at the species level, of the pistachio pathogen as a X. translucens. In the gyrB-based phylogeny, strains of the pistachio pathogen clustered among the X. translucens pathovars as two distinct lineages. Integron screening revealed that the cassette arrays of strains of the pistachio pathogen were different from those of other Xanthomonas species, and again distinguished two groups. Together with previously reported pathogenicity data, these results confirm that the pistachio pathogen is a new pathovar of X. translucens and allow hypotheses about its origin. The proposed name is Xanthomonas translucens pv. pistaciae pv. nov. 相似文献
179.
180.
Guillaume Cuoco Carole Mathe Paul Archier Mohamed El Maâtaoui Cathy Vieillescazes 《Phytochemical analysis : PCA》2009,20(6):484-490
Introduction – Madder (Rubia tinctorum) has been used since ancient times as a source of pigments for dyeing and painting. Madder dyes are localised in roots and the native chemical population is composed of glycosiled and aglycone compounds. The aim of this study is to elaborate an efficient extraction process without any chemical denaturation of dyes. Objective – To compare an optimised ultrasonic process, using for madder dye extraction, with two conventional procedures and to determine the efficiency of ultrasound on these vegetable matrix. Methodology – Madder roots were extract in a methanol–water mixture in 37 : 63 (v/v) for ultrasound and 80 : 20 (v/v) for reflux and agitation. HPLC‐PAD analyses showed the anthraquinone proportion for each extraction process and their denaturing effects. Finally, cytohistological observations were made to show the consequence of each process on the cell organisation in madder roots. Results – The results showed that the amount of extracted dyes was higher with UAE than with agitation and reflux. HPLC‐PAD analysis revealed that the anthraquinone composition differed according to the extraction procedure. The UAE extracts presented an important richness in terms of anthraquinonic compounds that suggests a preserving effect. Cytohistological observations showed that the main alterations concerned the cell walls of phloem. After UAE the walls exhibited numerous pitted areas reflecting an ultrasound‐induced cavitation that enhances the extraction effectiveness of this method. Conclusion – The study has shown the improvement of madder roots extraction both quantitatively and qualitatively using the efficiency of ultrasound‐assisted extraction in comparison with magnetic agitation and reflux techniques. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献