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31.
Mahesh Pandit Maheshwor Timilshina Ye Gu Suman Acharya Yeonseok Chung Sang-Uk Seo Jae-Hoon Chang 《Experimental & molecular medicine》2022,54(8):1214
Allergic inflammation is a T helper 2 (Th2) cell-driven pathophysiological phenomenon, but the mechanism by which the metabolic cascade affects Th2 cell differentiation remains unclear. In this study, we investigated the roles of AMP-activated protein kinase (AMPK) and intracellular energy sensors in Th2 cell differentiation and the pathogenesis of allergic inflammation. Accordingly, T-cell-specific AMPK or Sirtuin 1 (Sirt1)-knockout mice were subjected to allergic inflammation, and their Th2 cell responses were investigated. The results demonstrated that inducing allergic inflammation in AMPK- and Sirt1-knockout mice increased Th2 cell responses and exacerbated allergic phenotypes. Furthermore, treatment with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR), an activator of AMPK, ameliorated allergic inflammation in mice. Mechanistically, our findings revealed that AMPK repressed mechanistic target of rapamycin complex 2 (mTORC2), which downregulated the expression of suppressor of cytokine signaling 5 (SOCS5) in CD4+ T cells. In addition, the loss of AMPK signaling reduced SOCS5 expression and increased interleukin-4-STAT6–GATA3 axis-mediated Th2 cell differentiation. Finally, the T-cell-specific deletion of Rictor, a member of mTORC2, in Sirt1T-KO mice led to the reversal of allergic exacerbation to the level in control mice. Overall, our findings suggest that AMPK in CD4+ T cells inhibits the differentiation of Th2 cells by repressing mTORC2 and thus serves as a potential target for Th2 cell-associated diseases.Subject terms: Lymphocytes, Inflammation 相似文献
32.
Sirajudheen Anwar Jonaid Ahmad Malik Sakeel Ahmed Verma Abhishek Kameshwar Jowaher Alanazi Abdulwahab Alamri Nafees Ahemad 《Molecules (Basel, Switzerland)》2022,27(22)
Cancer is the leading cause of death and has remained a big challenge for the scientific community. Because of the growing concerns, new therapeutic regimens are highly demanded to decrease the global burden. Despite advancements in chemotherapy, drug resistance is still a major hurdle to successful treatment. The primary challenge should be identifying and developing appropriate therapeutics for cancer patients to improve their survival. Multiple pathways are dysregulated in cancers, including disturbance in cellular metabolism, cell cycle, apoptosis, or epigenetic alterations. Over the last two decades, natural products have been a major research interest due to their therapeutic potential in various ailments. Natural compounds seem to be an alternative option for cancer management. Natural substances derived from plants and marine sources have been shown to have anti-cancer activity in preclinical settings. They might be proved as a sword to kill cancerous cells. The present review attempted to consolidate the available information on natural compounds derived from plants and marine sources and their anti-cancer potential underlying EMT mechanisms. 相似文献
33.
Adullah Alotaibi Godwin U. Ebiloma Roderick Williams Ibrahim A. Alfayez Manal J. Natto Sameah Alenezi Weam Siheri Malik AlQarni John O. Igoli James Fearnley Harry P. De Koning David G. Watson 《Molecules (Basel, Switzerland)》2021,26(13)
Ethanolic extracts of samples of temperate zone propolis, four from the UK and one from Poland, were tested against three Trypanosoma brucei strains and displayed EC50 values < 20 µg/mL. The extracts were fractionated, from which 12 compounds and one two-component mixture were isolated, and characterized by NMR and high-resolution mass spectrometry, as 3-acetoxypinobanksin, tectochrysin, kaempferol, pinocembrin, 4′-methoxykaempferol, galangin, chrysin, apigenin, pinostrobin, cinnamic acid, coumaric acid, cinnamyl ester/coumaric acid benzyl ester (mixture), 4′,7-dimethoxykaempferol, and naringenin 4′,7-dimethyl ether. The isolated compounds were tested against drug-sensitive and drug-resistant strains of T. brucei and Leishmania mexicana, with the highest activities ≤ 15 µM. The most active compounds against T. brucei were naringenin 4′,7 dimethyl ether and 4′methoxy kaempferol with activity of 15–20 µM against the three T. brucei strains. The most active compounds against L. mexicana were 4′,7-dimethoxykaempferol and the coumaric acid ester mixture, with EC50 values of 12.9 ± 3.7 µM and 13.1 ± 1.0 µM. No loss of activity was found with the diamidine- and arsenical-resistant or phenanthridine-resistant T. brucei strains, or the miltefosine-resistant L. mexicana strain; no clear structure activity relationship was observed for the isolated compounds. Temperate propolis yields multiple compounds with anti-kinetoplastid activity. 相似文献
34.
Muhammad Imran Malik Tooba Mahboob Shakil Ahmed 《Analytical and bioanalytical chemistry》2014,406(25):6311-6317
Poly(2-vinylpyridine)s (P2VPs) are important polymers with extensive applications in modern day material science. P2VP is an exceptional case for liquid chromatography because of certain polar interactions with most of the stationary phases. In the present study, we established the critical adsorption point (CAP) of P2VP for the first time. The effectiveness of the method is demonstrated by analyses of blends and block copolymers of P2VP and PMMA. The CAP of PMMA is established for determination of molar mass of P2VP component of above mentioned blends and block copolymers. The methods successfully demonstrate the separation of both types of homopolymers from the rest of the samples in conjunction with the determination of molar mass distribution of noncritical block or component. Graphical Abstract
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35.
36.
Alkali Metal and Alkaline Earth Metal Complexes with the Bis(borane‐diphenylphosphanyl)amido Ligand – Synthesis,Structures, and Catalysis for Ring‐Opening Polymerization of ϵ‐Caprolactone
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Jayeeta Bhattacharjee Suman Das T. Dhileep N. Reddy Hari Pada Nayek Bhabani S. Mallik Tarun K. Panda 《无机化学与普通化学杂志》2016,642(2):118-127
The syntheses of lithium and alkaline earth metal complexes with the bis(borane‐diphenylphosphanyl)amido ligand ( 1 ‐ H ) of molecular formulas [{κ2‐N(PPh2(BH3))2}Li(THF)2] ( 2 ) and [{κ3‐N(PPh2(BH3))2}2M(THF)2] [(M = Ca ( 3 ), Sr ( 4 ), Ba ( 5 )] are reported. The lithium complex 2 was obtained by treatment of bis(borane‐diphenylphosphanyl)amine ( 1 ‐ H ) with lithium bis(trimethylsilyl)amide in a 1:1 molar ratio via the silylamine elimination method. The corresponding homoleptic alkaline earth metal complexes 3 – 5 were prepared by two synthetic routes – first, the treatment of metal bis(trimethylsilyl)amide and protio ligand 1 ‐ H via the elimination of silylamine, and second, through salt metathesis reaction involving respective metal diiodides and lithium salt 2 . The molecular structures of lithium complex 2 and barium complex 5 were established by single‐crystal X‐ray diffraction analysis. In the solid‐state structure of 2 , the lithium ion is ligated by amido nitrogen atoms and hydrogen atoms of the BH3 group in κ2‐coordination of the ligand 1 resulting in a distorted tetrahedral geometry around the lithium ion. However, in complex 5 , κ3‐coordination of the ligand 1 was observed, and the barium ion adopted a distorted octahedral arrangement. The metal complex 5 was tested as catalyst for the ring opening polymerization of ?‐caprolactone. High activity for the barium complex 5 towards ring opening polymerization (ROP) of ?‐caprolactone with a narrow polydispersity index was observed. Additionally, first‐principle calculations to investigate the structure and coordination properties of alkaline earth metal complexes 3 – 5 as a comparative study between the experimental and theoretical findings were described. 相似文献
37.
Synthesis of 3‐aminomethylidenechroman‐2‐carboxamides by a Sequential One‐pot Three Component Reaction and by Post‐Passerini Condensation Modification 下载免费PDF全文
Jaydip Ghosh Suman Kalyan Panja Sourav Maiti Pritam Biswas Tapas Sarkar Chandrakanta Bandyopadhyay 《Journal of heterocyclic chemistry》2016,53(2):449-456
3‐Arylaminomethylidenechroman‐2‐carboxamide has been synthesized by a one‐pot three component reaction among 3‐formylchromone, aromatic amine, and cyclohexyl isocyanide. 3‐(N‐alkylsubstitued/unsubstituted)aminomethylidenechroman‐2‐carboxamides were synthesized by heating Passerini products derived from chromone‐3‐carbaldehyde with different aliphatic primary amines. The products obtained from the reactions of aliphatic primary amines readily form chromeno[2,3‐c]pyrrole when heated in acetic acid. Bischromanones have also been synthesized using this methodology. 相似文献
38.
39.
S. Nasir G. Asghar Muhammad Ali Malik M. Anis-ur-Rehman 《Journal of Sol-Gel Science and Technology》2011,59(1):111-116
Zinc doped nickel ferrite nanoparticles having the general formula Ni1−xZnxFe2O4 (x = 0.1, 0.2, 0.3, 0.4, 0.5) were prepared with simplified sol–gel method. The structural and dielectric properties of these
samples sintered at 750 ± 5 °C were studied. X-ray diffraction patterns confirm the single phase spinel structure for prepared
samples. The scanning electron microscope images indicated that the particle size of the samples lies in the nanometer regime.
The dielectric constant (εr) and dielectric loss tangent (tan δ) of nanocrystalline nickel ferrites were investigated as a function of frequency and
Zn concentration. The dependence of εr and tan δ on the frequency of the alternating applied electric field is in accordance with the Maxwell–Wagner model. The
prepared samples have a lowest dielectric constant compared to the already reported samples of the same composition to the
best of our knowledge. The effect of Zn doping on the dielectric properties of nickel ferrites is explained on the basis of
cations distribution in the crystal structure. 相似文献
40.
Maqsood Ahmad Malik Firdosa Nabi 《Journal of Dispersion Science and Technology》2013,34(10):1396-1400
Stoichiometry of the redox reaction of vanadium(V) by ascorbic acid (H2A) has been experimentally determined to be H2A + 2V(V) → A + 2V(IV) + 2H + . Evidence of induced polymerization of acrylonitrile and the reduction of mercuric chloride indicates that a free-radical mechanism operates during the course of reaction. Vanadium(V) is only reduced to vanadium(IV). The kinetics of this redox reaction have been investigated spectrophotometrically at 35°C in acidic media of H2SO4. In this kinetic study we have observed the nature of vanadium(V)-H2A interaction in presence of anionic surfactant of SDS. In V(V)-H2A system, the addition of anionic surfactant (SDS) enhanced the reaction rate and shows catalytic effect. This trend was explained by the incorporation/solubilization of vanadium(V) and ascorbic acid in the Stern layer. 相似文献