The compound 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an environmental contaminant, is a potent ligand for aryl hydrocarbon receptor (AhR). In the current study, we made an exciting observation that naive C57BL/6 mice that were exposed i.p. to TCDD showed massive mobilization of myeloid-derived suppressor cells (MDSCs) in the peritoneal cavity. These MDSCs were highly immunosuppressive and attenuated Con A–induced hepatitis upon adoptive transfer. TCDD administration in naive mice also led to induction of several chemokines and cytokines in the peritoneal cavity and serum (CCL2, CCL3, CCL4, CCL11, CXCL1, CXCL2, CXCL5, CXCL9, G-CSF, GM-CSF, VEGF, and M-CSF) and chemokine receptors on MDSCs (CCR1, CCR5, and CXCR2). Treatment with CXCR2 or AhR antagonist in mice led to marked reduction in TCDD-induced MDSCs. TCDD-induced MDSCs had high mitochondrial respiration and glycolytic rate and exhibited differential microRNA (miRNA) expression profile. Specifically, there was significant downregulation of miR-150-5p and miR-543-3p. These two miRNAs targeted and enhanced anti-inflammatory and MDSC-regulatory genes, including IL-10, PIM1, ARG2, STAT3, CCL11 and its receptors CCR3 and CCR5 as well as CXCR2. The role of miRs in MDSC activation was confirmed by transfection studies. Together, the current study demonstrates that activation of AhR in naive mice triggers robust mobilization of MDSCs through induction of chemokines and their receptors and MDSC activation through regulation of miRNA expression. AhR ligands include diverse compounds from environmental toxicants, such as TCDD, that are carcinogenic to dietary indoles that are anti-inflammatory. Our studies provide new insights on how such ligands may regulate health and disease through induction of MDSCs.
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As risks affecting the most important and vital to organizations as a tourist aspects of the market share and styles tourist
... Show MoreFuture wireless networks will require advance physical-layer techniques to meet the requirements of Internet of Everything (IoE) applications and massive communication systems. To this end, a massive MIMO (m-MIMO) system is to date considered one of the key technologies for future wireless networks. This is due to the capability of m-MIMO to bring a significant improvement in the spectral efficiency and energy efficiency. However, designing an efficient downlink (DL) training sequence for fast channel state information (CSI) estimation, i.e., with limited coherence time, in a frequency division duplex (FDD) m-MIMO system when users exhibit different correlation patterns, i.e., span distinct channel covariance matrices, is to date ve
... Show MoreThe study scrutinises intermingled relations between children literature and some ecological issues. Such interwoven relationships would be highly recommended to encourage children to explore and identify themselves with nature from early ages to avoid facing an extreme experience later on. The research limits its scope to two novels Suzanne Collins’ (1962) The Hunger Games trilogy (2003-2007) and William Golding’s (1911-1993) Lord of the Flies (1954), and both novels have no direct connections with Ecology and the Eco-consciousness, yet it offers an insightful description about Man’s experience with Nature. Moreover, it raises serious moral questions, raises awareness, heals wounds and suggests solutions for the problems th
... Show MoreNerium oleander known as oleander has belonged to the poisonous plants its habitat in a tropical andsubtropical region. The chemical analysis with GC-Mass of the alcoholic extract of oleander leaves revealedthat this plant has many chemical compounds more than 80 compounds and high-peaks about 29 compoundswhich are represented by alkaloids, phenol, terpenes, and fatty acid. HPLC analysis showed many essentialoils that have many biological effects.To evaluate the antibacterial activity of the alcoholic extract of N. oleander against locally isolatedPseudomonas aeroginosa the broth micro-dilution method was adapted to different concentrations werestarted from 3.9 to1000 mg/ml. The results revealed that the alcoholic extract has antiba
... Show MoreExcess alcohol consumption is associated with numerous metabolic changes and homeostasis disturbances of many macro- and micro-elements in the body. It has been associated with multiple pathologies at all levels. In the digestive apparatus, alcohol has generally been related to its toxic effects upon the liver. Alpha-1 antitrypsin (α-1 AT or AAT) plays an important role in controlling inflammation, coagulation and repair mechanisms in the body and most α-1 AT in the body is produced by the liver; from the other hand, Intrinsic factor (IF), which is a glycoprotein produced by the parietal cells of the stomach is necessary for the absorption of vitamin B12 in the small intestine. This study was designed to assess serum levels of α-1 AT and
... Show MoreThis study aims to identify the teaching problems that teachers of students with intellectual disabilities face, in addition to exploring the solutions suggested by them in order to overcome such problems or challenges. The researchers used a qualitative approach in order to understand the teachers' perceptions about these problems in a more in-depth way. The interview tools (in-depth and semi-structured interviews) were used to collect data from (3) female teachers from special education programs in the Asir region. The results revealed a number of themes including problems related to students, teachers and the teaching methods they use, curricula, school environment, and school administration. Moreover, the results indicated that famil
... Show MoreObjectives: Six different Schiff bases were synthesized from ampicillin and amoxicillin with isatin, 5-bromoisatin, and 5-nitroisatin. Methods: Ampicillin and Amoxicillin are linked directly through their α-amino groups to the acyl side chain with isatin and isatin derivatives by nucleophilic addition using glacial acetic acid as a catalyst. Results: chemical structures of these Schiff bases were confirmed using FTIR, 1H NMR and elemental microanalysis. The antibacterial activity was evaluated by measuring minimum inhibitory concentration (MIC) values and showed various degrees of antibacterial activities when compared with parent drugs. Compounds 1a and 2b, which are the Schiff bases of ampicillin and amoxicillin with isatin, showed very
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