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排序方式: 共有789条查询结果,搜索用时 15 毫秒
61.
Clarisse Roblin Steve Chiumento Cdric Jacqueline Eric Pinloche Cendrine Nicoletti Hamza Olleik Elise Courvoisier-Dezord Agns Amouric Christian Basset Louis Dru Marie Ollivier Aurlie Bogey-Lambert Nicolas Vidal Mohamed Atta Marc Maresca Estelle Devillard Victor Duarte Josette Perrier Mickael Lafond 《International journal of molecular sciences》2021,22(6)
The world is on the verge of a major antibiotic crisis as the emergence of resistant bacteria is increasing, and very few novel molecules have been discovered since the 1960s. In this context, scientists have been exploring alternatives to conventional antibiotics, such as ribosomally synthesized and post-translationally modified peptides (RiPPs). Interestingly, the highly potent in vitro antibacterial activity and safety of ruminococcin C1, a recently discovered RiPP belonging to the sactipeptide subclass, has been demonstrated. The present results show that ruminococcin C1 is efficient at curing infection and at protecting challenged mice from Clostridium perfringens with a lower dose than the conventional antibiotic vancomycin. Moreover, antimicrobial peptide (AMP) is also effective against this pathogen in the complex microbial community of the gut environment, with a selective impact on a few bacterial genera, while maintaining a global homeostasis of the microbiome. In addition, ruminococcin C1 exhibits other biological activities that could be beneficial for human health, as well as other fields of applications. Overall, this study, by using an in vivo infection approach, confirms the antimicrobial clinical potential and highlights the multiple functional properties of ruminococcin C1, thus extending its therapeutic interest. 相似文献
62.
Isabelle Duroux-Richard Jimena Cuenca Clara Ponsolles Alejandro Badilla Pi?eiro Fernando Gonzalez Christine Roubert Roser Areny Rosa Chea Jacqueline Pefaur Yves-Marie Pers Fernando E. Figueroa Christian Jorgensen Maroun Khoury Florence Apparailly 《International journal of molecular sciences》2015,16(8):16953-16965
MicroRNAs control the differentiation and function of B cells, which are considered key elements in the pathogenesis of systemic lupus erythematosus (SLE). However, a common micro(mi)RNA signature has not emerged since published data includes patients of variable ethnic background, type of disease, and organ involvement, as well as heterogeneous cell populations. Here, we aimed at identifying a miRNA signature of purified B cells from renal and non-renal severe SLE patients of Latin American background, a population known to express severe disease. Genome-wide miRNA expression analyses were performed on naive and memory B cells and revealed two categories of miRNA signatures. The first signature represents B cell subset-specific miRNAs deregulated in SLE: 11 and six miRNAs discriminating naive and memory B cells of SLE patients from healthy controls (HC), respectively. Whether the miRNA was up or down-regulated in memory B cells as compared with naive B cells in HC, this difference was abolished in SLE patients, and vice versa. The second signature identifies six miRNAs associated with specific pathologic features affecting renal outcome, providing a further understanding for SLE pathogenesis. Overall, the present work provided promising biomarkers in molecular diagnostics for disease severity as well as potential new targets for therapeutic intervention in SLE. 相似文献
63.
Shank Laura K.; Kaufman Jacqueline; Leffard Stacie; Warschausky Seth 《Canadian Metallurgical Quarterly》2010,55(2):188
Objective: To examine between-groups differences in the associations between aspects of processing speed assessed with an inspection time task and attention-deficit/hyperactivity disorder (ADHD) symptoms. Research Design: Two groups comprising 34 children with cerebral palsy (CP) and 70 nonaffected peers (control), ages 8–16 years, participated in a prospective correlational study. Measures included a visual inspection time task and the Conners' Parent Rating Scale—Revised: Long Version. Results: Children with CP exhibited significantly slower processing speed and more symptoms of inattention and hyperactivity than controls. Significant associations between inspection time and ADHD symptoms were found only in the control group. Conclusions: Findings have implications for clinical assessment and understanding of attentional risks associated with CP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
Geddes Jacqueline; Ratcliff Roger; Allerhand Michael; Childers Russ; Wright Rohana J.; Frier Brian M.; Deary Ian J. 《Canadian Metallurgical Quarterly》2010,24(5):652
Objective: Previous research has demonstrated that hypoglycemia causes reaction times to be slower and more variable. Reaction time tests, however, use multiple cognitive and noncognitive processes. This study is the first to use a validated sequential sampling model (diffusion model) applied to results obtained from a simple 2-choice task in adult humans to assess the effects of hypoglycemia on the basic parameters of decision making. Method: Fourteen adult volunteers were tested on a numerosity discrimination task with and without reduced blood glucose concentrations. The results were analyzed with a model that dissects the components of processing that underlie decisions: the quality of the information on which a decision is based (drift rate), the critical amount of evidence that must be accumulated before a decision is made (boundary separation), and the time taken by nondecision processes. Results: Hypoglycemia resulted in a reduction of mean drift rate from 0.290 to 0.211, t(13) = 4.10, p 相似文献
65.
Ayuka T. Fombong Jacqueline M. Mutunga Peter E. A. Teal Baldwyn Torto 《Journal of chemical ecology》2016,42(10):1063-1069
The Afro-tropical scarab Oplostomus haroldi (Witte) is a pest of honeybees in East Africa with little information available on its chemical ecology. Recently, we identified a female-produced contact sex pheromone, (Z)-9-pentacosene, from the cuticular lipids that attracted males. Here, we investigated the kairomonal basis of host location in O. haroldi. We used coupled gas chromatography/electroantennographic detection (GC/EAD) and GC/mass spectrometry to identify antennally-active compounds from volatiles collected from honeybee colonies. Antennae of both sexes of the beetle consistently detected seven components, which were identified as 3-hydroxy-2-butanone, 2,3-butanediol, butyl acetate, isopentyl acetate, butyl butyrate, hexyl acetate, and methyl benzoate. In olfactometer bioassays, both sexes responded to the full seven-component synthetic blend over solvent controls, but chose honeybee colony odors over the blend. These findings suggest that the seven compounds are components of a kairomone from honeybee colonies used by O. haroldi. 相似文献
66.
The health risks and benefits of the various methods of birth control vary not only according to the method used, but with the age and other characteristics of the user. For example, the Pill is the most effective and generally the safest method for teenagers. Mortality from Pill use could be reduced enormously if Pill users stopped smoking, if women did not take the Pill past age 35, and if no women took high-dose Pills. If health risks were the only consideration, a woman's safest course would be to start contraception with the Pill, continue with that method for about four years, have the number of children she desires by her mid-twenties, and then persuade her male partner to have a vasectomy. The most notable benefits of contraceptive use are some protection conferred by the Pill against ovarian and endometrial cancer, pelvic inflammatory disease, ectopic pregnancy, ovarian retention cysts, and iron deficiency anemia; considerable protection by the barrier methods, especially the condom, against sexually transmitted disease, including AIDS; and protection by male and female sterilization against ectopic pregnancy. The major disadvantages are increased risk of heart attack and stroke associated with Pill use (mainly among those over 35 who smoke); significant risk of pelvic inflammatory disease associated with IUD use; surgical complications and anesthesia deaths from sterilization and abortion procedures; and complications of pregnancy from failure of barrier methods and of periodic abstinence. 相似文献
67.
The integration of games into therapy provides an innovative therapeutic tool that may potentially enhance the therapeutic process. This article explores the use of games in relation to the theoretical constructs of social learning, cognitive behavioral, psychoanalytic, and gestalt theories. In addition, the author discusses types of games, therapeutic components of games, and areas that impact the use of this therapeutic tool. Finally, the article presents a method explaining how counselors can modify existing games and create their own games to incorporate within the therapeutic process for individual, family, and group therapy sessions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Grigsby Jim; Kaye Kathryn; Kowalsky Jacqueline; Kramer Andrew M. 《Canadian Metallurgical Quarterly》2002,47(3):291
Objective: To assess the relationship between behavioral self-regulation and functional status among older rehabilitation inpatients. Study Design: Prospective outcome study. Setting: Fourteen inpatient rehabilitation units and skilled nursing facilities. Participants: Two hundred twelve older adults following hip fracture or replacement. Measures: Mini Mental State Exam (MMSE), Geriatric Depression Scale, Behavioral Dyscontrol Scale (BDS), and nurse-rated functioning on activities of daily living (ADLs) and the Barthel Index. Results: Risk-adjusted analyses found the BDS to be strongly associated with all 11 ADLs and the Barthel Index. The MMSE made an additional contribution to 4 models. Conclusion: The results suggest that the ability to use intentions to guide purposeful behavior is an important contributor to functioning among older adults, affecting rehabilitation potential. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
70.
Ourida Iguerb Sophie Demoustier‐Champagne Jacqueline Marchand‐Brynaert Daniel Daoust Michel Sclavons Jacques Devaux 《Polymer International》2008,57(8):957-964
BACKGROUND: The surface properties of high‐density polyethylene and linear low‐density polyethylene were modified by grafting urethane monoacrylate monomer under UV irradiation. This graft polymerization was carried out on native substrates and on substrates pre‐treated by wet oxidation, for different oxidation times. RESULTS: As the urethane monacrylate layer is crosslinked, its grafting efficiency was checked by dissolving the polyethylene substrates in hot toluene. Grafting was evidenced by Fourier transform infrared spectroscopy of the obtained residues, which showed that both the characteristic urethane acrylate (3350 cm?1) and polyethylene (2920, 730 and 720 cm?1) bands were observable for any polyethylene oxidation time. For an oxidation time longer than 10 hours, acrylate grafting was homogeneous and the grafted surface was smooth with a roughness of less than 10 nm. In addition, X‐ray photoelectron spectroscopy analysis of the residues revealed that O/C had an average value of 0.19, which is lower than the value corresponding to pure acrylate (0.42), whereas N/C had an average value of 0.068, also lower than that of pure acrylate (0.09), thus confirming the grafting. CONCLUSION: A urethane monoacrylate layer was grafted on native and oxidized polyethylene films. For highly oxidized films, the grafted surfaces are smooth and homogeneous. Copyright © 2008 Society of Chemical Industry 相似文献