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106.
Protective Effect of Thymus serrulatus Essential Oil on Cadmium-Induced Nephrotoxicity in Rats,through Suppression of Oxidative Stress and Downregulation of NF-κB,iNOS, and Smad2 mRNA Expression     
Mohd Nazam Ansari  Najeeb Ur Rehman  Aman Karim  Faisal Imam  Abubaker M. Hamad 《Molecules (Basel, Switzerland)》2021,26(5)
The purpose of the research was to examine the protective effect of essential oil from Thymus serrulatus Hochst. ex Benth. (TSA oil) against cadmium (Cd)-induced renal toxicity. The experimental protocol was designed using 30 healthy adult Wistar albino rats allocated into five groups containing six animals in each group. Group 1 was treated as normal control and groups 2, 3, 4, and 5 were treated with cadmium chloride (CdCl2, 3 mg/kg, IP) for 7 days. Group 3 was also treated with silymarin (100 mg/kg, PO) as a standard group, while groups 4 and 5 were administered with TSA oil at doses of 100 and 200 mg/kg PO, respectively. The nephrotoxicity was measured with various parameters such as kidney function markers, oxidative stress markers (glutathione (GSH) and malondialdehyde (MDA)), and messenger ribonucleic acid (mRNA) expression levels of inflammatory factors. The histological studies were also evaluated in the experimental protocol. The CdCl2-treated groups showed a significant increase in the levels of serum kidney function markers along with MDA levels in kidney homogenate. However, renal GSH level was found to be reduced significantly. It was found that CdCl2 significantly upregulated the nuclear factor levels of kappaB (NF-κB p65), inducible nitric oxide synthase (iNOS), and small mothers against decapentaplegic (Smad2) as compared to the normal control group. On the other hand, TSA oil significantly improved the increased levels of serum kidney function markers, non-enzymatic antioxidants, and lipid peroxidation. In addition, TSA oil significantly downregulated the increased expression of NF-κB p65, iNOS, and Smad2 in Cd-intoxicated rats. Moreover, the histological changes in the tissue samples of the kidney of Cd-treated groups were significantly ameliorated in the silymarin- and TSA-oil-treated groups. The present study reveals that TSA oil ameliorates Cd-induced renal injury, and it is also proposed that the observed nephroprotective effect could be due to the antioxidant potential of TSA oil and healing due to its anti-inflammatory action.  相似文献   
107.
108.
Relative difference sets fixed by inversion (III)—Cocycle theoretical approach     
Yu Qing Chen 《Discrete Mathematics》2008,308(13):2764-2775
In this paper, we give a characterization of a group G which contains a semiregular relative difference set R relative to a central subgroup N containing the commutator subgroup [G,G] of G such that 1∈R and rRr=R for all rR. In particular, these relative difference sets are fixed by inversion and inner automorphisms of the group are multipliers. We also present a construction of such relative difference sets.  相似文献   
109.
Best approximation and moduli of smoothness: Computation and equivalence theorems   总被引:1,自引:0,他引:1  
Sergey Tikhonov   《Journal of Approximation Theory》2008,153(1):19-39
In this paper we investigate the trigonometric series with the β-general monotone coefficients. First, we study the uniform convergence criterion. The estimates of best approximations and moduli of smoothness of the series in uniform metrics are obtained in terms of coefficients. These results imply several important relations between moduli of smoothness of different orders (in particular, Marchaud-type inequality) and best approximations.  相似文献   
110.
Newsvendor equations for optimal reorder levels of serial inventory systems with fixed batch sizes     
M.K. Doru  G.J. van Houtum  A.G. de Kok 《Operations Research Letters》2008,36(5):551-556
We consider a stochastic serial inventory system with a given fixed batch size per stage and linear inventory holding and penalty costs. For this system, echelon stock (R,nQ) policies are known to be optimal. On the basis of new average costs formulas, we obtain newsvendor equations for the optimal reorder levels.  相似文献   
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101.
Persistent inflammatory reactions promote mucosal damage and cause dysfunction, such as pain, swelling, seizures, and fever. Therefore, in this study, in order to explore the anti-inflammatory effect of 6-methylcoumarin (6-MC) and suggest its availability, macrophages were stimulated with lipopolysaccharide (LPS) to conduct an in vitro experiment. The effects of 6-MC on the production and levels of pro-inflammatory cytokines (interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α) and inflammatory mediators (nitric oxide (NO), prostaglandin E2 (PGE2)) in LPS-stimulated RAW 264.7 cells were examined. The results showed that 6-MC reduced the levels of NO and PGE2 without being cytotoxic. In addition, it was demonstrated that the increase in the expression of pro-inflammatory cytokines caused by LPS stimulation, was decreased in a concentration-dependent manner with 6-MC treatment. Moreover, Western blot results showed that the protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), which increased with LPS treatment, were decreased by 6-MC treatment. Mechanistic studies revealed that 6-MC reduced the phosphorylation of the mitogen-activated protein kinase (MAPK) family and IκBα in the MAPK and nuclear factor-kappa B (NF-κB) pathways, respectively. These results suggest that 6-MC is a potential therapeutic agent for inflammatory diseases that inhibits inflammation via the MAPK and NF-κB pathways.  相似文献   
102.
Ten polyketide derivatives (1–10), including a new natural product named (E)-2,4-dihydroxy-3-methyl-6-(2-oxopent-3-en-1-yl) benzaldehyde (1), and five known diketopiperazines (11–15), were isolated from the mangrove-sediment-derived fungus Aspergillus sp. SCSIO41407. The structures of 1–15 were determined via NMR and MS spectroscopic analysis. In a variety of bioactivity screening, 3 showed weak cytotoxicity against the A549 cell line, and 2 exhibited weak antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Compounds 3, 5, and 6 showed inhibition against acetylcholinesterase (AChE) with IC50 values of 23.9, 39.9, and 18.6 μM. Compounds 11, 12, and 14 exhibited obvious inhibitory activities of lipopolysaccharide (LPS)-induced nuclear factor-κB (NF-κB) with IC50 values of 19.2, 20.9, and 8.7 μM, and they also suppressed RANKL-induced osteoclast differentiation in bone marrow macrophages cells (BMMCs), with the concentration of 5 μM. In silico molecular docking with AChE and NF-κB p65 protein were also performed to understand the inhibitory activities, and 1, 11–14 showed obvious protein/ligand-binding effects to the NF-κB p65 protein.  相似文献   
103.
We performed STM/STS measurements on superconducting Bi2212 and La-Bi2201 in order to study the nondispersive two-dimensional (2D) electronic superstructure, namely the so-called checkerboard. The nondispersive checkerboard clearly appears within the pairing gap in both systems, although the period is different between Bi2212 (∼4a×4a) and La-Bi2201 (∼5a×5a). We point out that the nondispersive checkerboard originates in hole-pairs and/or quasiparticles around the antinodes of the d-wave gap, and interrelates with the spatially inhomogeneous pairing gap.  相似文献   
104.
We present ab initio calculation results for electron-phonon (e-ph) contribution to hole lifetime broadening of the surface state on Al(0 0 1). We show that e-ph coupling in this state is significantly stronger than in bulk Al at the Fermi level. It makes the e-ph decay channel very important in the formation of the hole decay in the surface state at . We also present the results for e-e lifetime broadening in a quantum-well state in 1 ML K/Cu(1 1 1). We show that this contribution is not negligible and is much larger than that in a surface state on Ag(1 1 1).  相似文献   
105.
In this paper, we use the Leray–Schauder degree theory to establish new results on the existence and uniqueness of anti-periodic solutions for a class of nonlinear nth-order differential equations with delays of the form
x(n)(t)+f(t,x(n−1)(t))+g(t,x(tτ(t)))=e(t).
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