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991.
Valentina Rafaela Herrera Millar Laura Mangiavini Umberto Polito Barbara Canciani Van Thi Nguyen Federica Cirillo Luigi Anastasia Giuseppe Maria Peretti Silvia Clotilde Modina Alessia Di Giancamillo 《International journal of molecular sciences》2021,22(13)
The meniscus possesses low self-healing properties. A perfect regenerative technique for this tissue has not yet been developed. This work aims to evaluate the role of hypoxia in meniscal development in vitro. Menisci from neonatal pigs (day 0) were harvested and cultured under two different atmospheric conditions: hypoxia (1% O2) and normoxia (21% O2) for up to 14 days. Samples were analysed at 0, 7 and 14 days by histochemical (Safranin-O staining), immunofluorescence and RT-PCR (in both methods for SOX-9, HIF-1α, collagen I and II), and biochemical (DNA, GAGs, DNA/GAGs ratio) techniques to record any possible differences in the maturation of meniscal cells. Safranin-O staining showed increments in matrix deposition and round-shape “fibro-chondrocytic” cells in hypoxia-cultured menisci compared with controls under normal atmospheric conditions. The same maturation shifting was observed by immunofluorescence and RT-PCR analysis: SOX-9 and collagen II increased from day zero up to 14 days under a hypoxic environment. An increment of DNA/GAGs ratio typical of mature meniscal tissue (characterized by fewer cells and more GAGs) was observed by biochemical analysis. This study shows that hypoxia can be considered as a booster to achieve meniscal cell maturation, and opens new opportunities in the field of meniscus tissue engineering. 相似文献
992.
Julie Goulet Geneviève Nadeau Annie Lapointe Beno?t Lamarche Simone Lemieux 《Nutrition journal》2004,3(1):13
Objective
To evaluate the validity (study 1) and the reproducibility (study 2) of an interviewer-administered food frequency questionnaire (FFQ). 相似文献993.
Controlled release of nitrogen‐source fertilizers by natural‐oil‐based poly(urethane) coatings: The kinetic aspects of urea release 下载免费PDF全文
Urea is the most common source of nitrogen fertilizer, but it has serious disadvantages with respect to volatilization and leaching; these can be controlled by polymeric coatings on the granules. However, the effectiveness of this strategy depends on the formed polymer presenting good adhesion, reactivity with the urea surface, uniformity, and efficient release kinetics control. Therefore, in this study, we evaluated the release kinetics of urea coated by polyurethane produced from two oils (soybean and castor) by analyzing the influence of the thickness, coating stability, deposition interface, and total release time. The results demonstrate that castor oil produced superior materials, which achieved a total release time in water immersion of over 40 days with a total coating mass of less than 4% of the total mass. The good interface suggested that this material may produce coatings of good quality and long release times with minimum thickness, and this will maximize the total nitrogen present in the granule. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43790. 相似文献
994.
Gilberto Ruiz-Deya Jaime Matta Jarline Encarnacin-Medina Carmen Ortiz-Sanchz Julie Dutil Ryan Putney Anders Berglund Jasreman Dhillon Youngchul Kim Jong Y. Park 《International journal of molecular sciences》2021,22(2)
In 2020, approximately 191,930 new prostate cancer (PCa) cases are estimated in the United States (US). Hispanic/Latinos (H/L) are the second largest racial/ethnic group in the US. This study aims to assess methylation patterns between aggressive and indolent PCa including DNA repair genes along with ancestry proportions. Prostate tumors classified as aggressive (n = 11) and indolent (n = 13) on the basis of the Gleason score were collected. Tumor and adjacent normal tissue were annotated on H&E (Haemotoxylin and Eosin) slides and extracted by macro-dissection. Methylation patterns were assessed using the Illumina 850K DNA methylation platform. Raw data were processed using the Bioconductor package. Global ancestry proportions were estimated using ADMIXTURE (k = 3). One hundred eight genes including AOX1 were differentially methylated in tumor samples. Regarding the PCa aggressiveness, six hypermethylated genes (RREB1, FAM71F2, JMJD1C, COL5A3, RAE1, and GABRQ) and 11 hypomethylated genes (COL9A2, FAM179A, SLC17A2, PDE10A, PLEKHS1, TNNI2, OR51A4, RNF169, SPNS2, ADAMTSL5, and CYP4F12) were identified. Two significant differentially methylated DNA repair genes, JMJD1C and RNF169, were found. Ancestry proportion results for African, European, and Indigenous American were 24.1%, 64.2%, and 11.7%, respectively. The identification of DNA methylation patterns related to PCa in H/L men along with specific patterns related to aggressiveness and DNA repair constitutes a pivotal effort for the understanding of PCa in this population. 相似文献
995.
Dr. Dimitri Alvarez Dorta Dr. Adeline Sivignon Dr. Thibaut Chalopin Dr. Tetiana I. Dumych Dr. Goedele Roos Dr. Rostyslav O. Bilyy Prof. David Deniaud Dr. Eva‐Maria Krammer Dr. Jérome de Ruyck Dr. Marc F. Lensink Dr. Julie Bouckaert Prof. Nicolas Barnich Dr. Sébastien G. Gouin 《Chembiochem : a European journal of chemical biology》2016,17(10):936-952
Blocking the adherence of bacteria to cells is an attractive complementary approach to current antibiotic treatments, which are faced with increasing resistance. This strategy has been particularly studied in the context of urinary tract infections (UTIs), in which the adhesion of pathogenic Escherichia coli strains to uroepithelial cells is prevented by blocking the FimH adhesin expressed at the tips of bacteria organelles called fimbriae. Recently, we extended the antiadhesive concept, showing that potent FimH antagonists can block the attachment of adherent‐invasive E. coli (AIEC) colonizing the intestinal mucosa of patients with Crohn′s disease (CD). In this work, we designed a small library of analogues of heptyl mannoside (HM), a previously identified nanomolar FimH inhibitor, but one that displays poor antiadhesive effects in vivo. The anomeric oxygen atom was replaced by a sulfur or a methylene group to prevent hydrolysis by intestinal glycosidases, and chemical groups were attached at the end of the alkyl tail. Importantly, a lead compound was shown to reduce AIEC levels in the feces and in the colonic and ileal mucosa after oral administration (10 mg kg?1) in a transgenic mouse model of CD. The compound showed a low bioavailability, preferable in this instance, thus suggesting the possibility of setting up an innovative antiadhesive therapy, based on the water‐soluble and non‐cytotoxic FimH antagonists developed here, for the CD subpopulation in which AIEC plays a key role. 相似文献
996.
Jitendriya Swain Clment Dezanet Hussein Chalhoub Marie Auquire Julie Kempf Jean-Luc Dcout Marie-Paule Mingeot-Leclercq 《International journal of molecular sciences》2021,22(16)
Development of novel therapeutics to treat antibiotic-resistant infections, especially those caused by ESKAPE pathogens, is urgent. One of the most critical pathogens is P. aeruginosa, which is able to develop a large number of factors associated with antibiotic resistance, including high level of impermeability. Gram-negative bacteria are protected from the environment by an asymmetric Outer Membrane primarily composed of lipopolysaccharides (LPS) at the outer leaflet and phospholipids in the inner leaflet. Based on a large hemi-synthesis program focusing on amphiphilic aminoglycoside derivatives, we extend the antimicrobial activity of 3′,6-dinonyl neamine and its branched isomer, 3′,6-di(dimethyloctyl) neamine on clinical P. aeruginosa, ESBL, and carbapenemase strains. We also investigated the capacity of 3′,6-homodialkyl neamine derivatives carrying different alkyl chains (C7–C11) to interact with LPS and alter membrane permeability. 3′,6-Dinonyl neamine and its branched isomer, 3′,6-di(dimethyloctyl) neamine showed low MICs on clinical P. aeruginosa, ESBL, and carbapenemase strains with no MIC increase for long-duration incubation. In contrast from what was observed for membrane permeability, length of alkyl chains was critical for the capacity of 3′,6-homodialkyl neamine derivatives to bind to LPS. We demonstrated the high antibacterial potential of the amphiphilic neamine derivatives in the fight against ESKAPE pathogens and pointed out some particular characteristics making the 3′,6-dinonyl- and 3′,6-di(dimethyloctyl)-neamine derivatives the best candidates for further development. 相似文献
997.
Three experiments asked whether subjects could retrieve information from a 2nd stimulus while they retrieved information from a 1st stimulus. Ss performed recognition judgments on each of 2 words that followed each other by 0, 250, and 1,000 msec (Experiment 1) or 0 and 300 msec (Experiments 2 and 3). In each experiment, reaction time to both stimuli was faster when the 2 stimuli were both targets (on the study list) or both lures (not on the study list) than when 1 was a target and the other was a lure. Each experiment found priming from the 2nd stimulus to the lst when both stimuli were targets. Reaction time to the 1st stimulus was faster when the 2 targets came from the same memory structure at study (columns in Experiment l; pairs in Experiment 2; sentences in Experiment 3) than when they came from different structures. This priming is inconsistent with discrete serial retrieval and consistent with parallel retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
999.
1000.
Anna B. Chwang Michael Hack Julie J. Brown 《Journal of the Society for Information Display》2005,13(6):481-486
Abstract— In this paper, the current status of flexible OLED (FOLED®) display development will be reviewed, including previous results for passive‐matrix displays on plastic and current progress on active‐matrix displays on steel foil. The displays incorporate high‐efficiency small‐molecule phosphorescence OLED (PHOLE?) technology. The ultimate goal is to develop high‐information‐content high‐performance long‐lived, and large‐area FOLED displays that can be pulled or rolled out from a smaller pen‐like housing. The strategy for achieving this goal will be presented. 相似文献