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Jeffrey A. Deiuliis Rafay Syed Dheeraj Duggineni Jessica Rutsky Palanivel Rengasamy Jie Zhang Kun Huang Bradley Needleman Dean Mikami Kyle Perry Jeffrey Hazey Sanjay Rajagopalan 《PloS one》2016,11(11)
Obesity in humans and mice is typified by an activated macrophage phenotype in the visceral adipose tissue (VAT) leading to increased macrophage-mediated inflammation. microRNAs (miRNAs) play an important role in regulating inflammatory pathways in macrophages, and in this study we compared miRNA expression in the VAT of insulin resistant morbidly obese humans to a non-obese cohort with normal glucose tolerance. miR-223-3p was found to be significantly upregulated in the whole omental tissue RNA of 12 human subjects, as were 8 additional miRNAs. We then confirmed that miR-223 upregulation was specific to the stromal vascular cells of human VAT, and found that miR-223 levels were unchanged in adipocytes and circulating monocytes of the non-obese and obese. miR-223 ablation increased basal / unstimulated TLR4 and STAT3 expression and LPS-stimulated TLR4, STAT3, and NOS2 expression in primary macrophages. Conversely, miR-223 mimics decreased TLR4 expression in primary macrophage, at the same time it negatively regulated FBXW7 expression, a well described suppressor of Toll-like receptor 4 (TLR4) signaling. We concluded that the abundance of miR-223 in macrophages significantly modulates macrophage phenotype / activation state and response to stimuli via effects on the TLR4/FBXW7 axis. 相似文献
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Jordyn Bergsveinson Benjamin J. Perry Gavin L. Simpson Christopher K. Yost Robert J. Schutzman Britt D. Hall Andrew D. S. Cameron 《Microbial biotechnology》2019,12(6):1199-1209
Cultivation of dedicated soil plots called ‘landfarms' is an effective technology for bioremediation of hydrocarbon waste generated by various industrial practices. To understand the influence of soil conditions on landfarm microbial communities, analysis of bacterial and fungal community structure using next-generation sequencing at different sections and depths was performed across a hydrocarbon-waste landfarm in Regina, Saskatchewan, Canada. While a core set of hydrocarbon-associated bacterial and fungal taxa are present throughout the landfarm, unique bacterial and fungal operational taxonomic units are differentially abundant at sections within the landfarm, which correlate with differences in soil physiochemical properties and management practices. Increased frequency of waste application resulted in strong positive correlations between bacterial community assemblages and elevated amounts of oil, grease and F3 – F4 hydrocarbon fractions. In areas of standing water and lower application of hydrocarbon, microbial community structure correlated with soil pH, trace nutrients and metals. Overall, diversity and structure of bacterial communities remain relatively stable across the landfarm, while in contrast, fungal community structure appears more responsive to soil oxygen conditions. Results are consistent with the hypothesis that years of bioremediation activity have shaped microbial communities; however, several management practices can be undertaken to increase efficiency of remediation, including the removal of standing water and soil tilling across the landfarm. 相似文献
145.
Gram-negative rod shaped bacterium Myxococcus xanthus DK1622 produces a smooth-type LPS. The structure of the polysaccharide O-chain and the core-lipid A region of the LPS has been determined by chemical and spectroscopic methods. The O-chain was built up of disaccharide repeating units having the following structure: -->6)-alpha-D-Glcp-(1-->4)-alpha-D-GalpNAc6oMe*-(1--> with partially methylated GalNAc residue. The core region consisted of a phosphorylated hexasaccharide, containing one Kdo residue, unsubstituted at O-4, and no heptose residues. The lipid A component consisted of beta-GlcN-(1-->6)-alpha-GlcN1P disaccharide, N-acylated with 13-methyl-C14-3OH (iso-C15-3OH), C16-3OH, and 15-methyl-C16-3OH (iso-C17-3OH) acids. The lipid portion contained O-linked iso-C16 acid. 相似文献
146.
A number of hypotheses have been presented regarding the originsof the metazoans and, more specifically, the Bilateria. Usingvarious phylogenetic analyses, characteristics have been mappedon phylogenetic trees to infer ancestral body plans and lifehistory strategies of those ancestors. Many arguments on theevolution of the Bilateria are based on the presumed homologyof certain characteristics of extant larva and adults, includingvarious ciliated bands involved in feeding and locomotion. Thisarticle considers a recent study indicating that the second,downstream-collecting, ciliated band in the veliger larva ofthe gastropod mollusc, Crepidula fornicata, is actually derivedfrom secondary trochoblasts (derived from second quartet micromeres),that normally form part of the prototrochal band found in otherspiralian phyla (Hejnol et al. 2007). Despite previous arguments,these new findings suggest that the second ciliated band inthe veliger larva is not homologous to the metatroch found inthe trochophore larva of some other spiralians, such as theannelid, Polygordius lacteus. In the latter case, the metatrochwas reported to be formed by a different set of lineage precursors(derived from third quartet micromeres) (Woltereck 1904). Thesefindings have important implications for the interpretationof various hypotheses related to the evolution of metazoan phyla. 相似文献
147.
The Global Contributions of Working Equids to Sustainable Agriculture and Livelihoods in Agenda 2030
Grace D. C. Diall O. Saville K. Warboys D. Ward P. Wild I. Perry B. D. 《EcoHealth》2022,19(3):342-353
EcoHealth - Small farmers produce most food in low- and middle-income countries and most small farmers rely on directly or indirectly working equids (WE). The lack of methods and metrics for... 相似文献
148.
Thomas Noe Perry Hager Souabni Chiara Rapisarda Rémi Fronzes Fabrice Giusti Jean-Luc Popot Manuela Zoonens Francesca Gubellini 《生物化学与生物物理学报:生物膜》2019,1861(2):466-477
Membrane protein (MP) complexes play key roles in all living cells. Their structural characterisation is hampered by difficulties in purifying and crystallising them. Recent progress in electron microscopy (EM) have revolutionised the field, not only by providing higher-resolution structures for previously characterised MPs but also by yielding first glimpses into the structure of larger and more challenging complexes, such as bacterial secretion systems. However, the resolution of pioneering EM structures may be difficult and their interpretation requires clues regarding the overall organisation of the complexes. In this context, we present BAmSA, a new method for localising transmembrane (TM) regions in MP complexes, using a general procedure that allows tagging them without resorting to neither genetic nor chemical modification. Labels bound to TM regions can be visualised directly on raw negative-stain EM images, on class averages, or on three-dimensional reconstructions, providing a novel strategy to explore the organisation of MP complexes. 相似文献
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Wilson Lim Bertrand Nyuykonge Kimberly Eadie Mickey Konings Juli Smeets Ahmed Fahal Alexandro Bonifaz Matthew Todd Benjamin Perry Kirandeep Samby Jeremy Burrows Annelies Verbon Wendy van de Sande 《PLoS neglected tropical diseases》2022,16(2)
Eumycetoma is a chronic subcutaneous neglected tropical disease that can be caused by more than 40 different fungal causative agents. The most common causative agents produce black grains and belong to the fungal orders Sordariales and Pleosporales. The current antifungal agents used to treat eumycetoma are itraconazole or terbinafine, however, their cure rates are low. To find novel drugs for eumycetoma, we screened 400 diverse drug-like molecules from the Pandemic Response Box against common eumycetoma causative agents as part of the Open Source Mycetoma initiative (MycetOS). 26 compounds were able to inhibit the growth of Madurella mycetomatis, Madurella pseudomycetomatis and Madurella tropicana, 26 compounds inhibited Falciformispora senegalensis and seven inhibited growth of Medicopsis romeroi in vitro. Four compounds were able to inhibit the growth of all five species of fungi tested. They are the benzimidazole carbamates fenbendazole and carbendazim, the 8-aminoquinolone derivative tafenoquine and MMV1578570. Minimal inhibitory concentrations were then determined for the compounds active against M. mycetomatis. Compounds showing potent activity in vitro were further tested in vivo. Fenbendazole, MMV1782387, ravuconazole and olorofim were able to significantly prolong Galleria mellonella larvae survival and are promising candidates to explore in mycetoma treatment and to also serve as scaffolds for medicinal chemistry optimisation in the search for novel antifungals to treat eumycetoma. 相似文献