A safe, practical and eco-friendly method for the switchable synthesis of sulfoxides and sulfones through visible-light-initiated oxygenation of sulfides at ambient temperature under ...transition-metal-, additives-free and minimal solvent conditions. The synergistic catalytic efforts between CF3SO2Na and 2-butoxyethyl ether represents the key promoting factor for the reaction.
The development of eco-friendly and switchable catalytic systems for the conversion of a sole raw-material into distinct high-value products is a particularly attractive concept and a daunting ...synthetic challenge. In the present work, the first example of efficient and selective oxidation of sulfides to sulfones and sulfoxides using molecular oxygen under clean conditions was established.
The first example of selective oxidation of sulfides to sulfones and sulfoxides using molecular oxygen under clean conditions was established. The desired products could be easily collected through recrystallization in large-scale preparation.
Aims
We aimed to investigate the role of receptor‐interacting protein 2 (RIP2) in regulation of stemness of glioma cells and chemotherapy resistance.
Methods
Plasmid transfection was used to ...overexpress RIP2. Chemical inhibitors were used to inhibit RIP2 or NF‐κB activity. Cancer stemness of glioma cells was investigated by sphere formation assays, clone formation assays, and xenograft tumor formation assays. The expression of RIP2, p‐NF‐κB, IκBα, CD133, or SOX‐2 was detected by Western blotting and immunofluorescence. Apoptosis was detected by flow cytometry. Immunohistochemical staining was used to detect the expression of RIP2, CD133, and SOX‐2 in xenograft tumor tissue. The effect of the RIP2/NF‐κB pathway on temozolomide (TMZ) resistance was evaluated by xenograft tumor assay.
Results
Transfection with RIP2 plasmid enhanced the sphere formation capability of U251 cells, clone formation capability, and xenograft tumor formation capability. RIP2 could mediate TMZ resistance by upregulating the expression of CD133 and SOX‐2 by activating the NF‐κB pathway. Both RIP2 inhibitor GSK583 and the NF‐κB inhibitor SC75741 could reverse the resistance of U251 cells to TMZ.
Conclusion
RIP2 mediates TMZ resistance by regulating the maintenance of stemness in glioma cells through NF‐κB. Interventions targeting the RIP2/NF‐κB pathway may be a new strategy for TMZ‐resistant gliomas.
RIP2 is involved in the induction of TMZ resistance in gliomas. The RIP2/NF‐κB signaling pathway induces enhanced stemness and plays an important role in TMZ resistance. The combined application of RIP2 or NF‐κB inhibitors and TMZ may be a new strategy for the treatment of RIP2‐related drug‐resistant gliomas.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
An eco-friendly, sustainable and practical method for the synthesis of various 5-organylselanyl uracils via the electrochemical selenylation of uracils and diorganyl diselenides at ambient ...temperature under oxidant- and external electrolyte-free conditions was developed.
Display omitted
An eco-friendly, sustainable and practical method for the efficient preparation of 5-organylselanyl uracils through the electrochemical selenylation of uracils and diorganyl diselenides at room temperature under oxidant- and external electrolyte-free conditions was developed.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
MicroRNA is an important regulator of glioblastoma. This study aims at validating microRNA-221 (miR-221) as a biomarker for glioblastoma, and understanding how miR-221 regulates glioblastoma ...progression. Using clinical samples, miR-221 expression was analyzed by quantitative reverse-transcriptase PCR (qPCR). SHG-44 cells were treated with anti-miR-221 or U87MG-derived exosomes followed by monitoring changes in cell viability, migration and temozolomide (TMZ) resistance. Bioinformatics approach was used to identify targets of miR-221. The interaction between miR-221 and its target,
DNM3
gene, was studied with dual-luciferase reporter assay, Spearman’s correlation analysis, and western blotting. To verify that RELA regulates miR-221 expression, RELA-expressing vector or shRNA was introduced into SHG-44 cells and its effect on miR-221 expression was monitored. Both tissue-level and exosomal miR-221 expression increased with glioma grades. In SHG-44 cells, downregulating miR-221 expression inhibited cell proliferation, migration, and TMZ resistance, whereas incubation with U87MG-derived exosomes exerted tumor-promoting effects. DNM3 gene is a target of miR-221. RELA induced miR-221 expression. In glioma, elevated miR-221 expression is a biomarker for glioma. DNM3 is a target of miR-221 and RELA regulates miR-221 expression. The RELA/miR-221 axis is a target for glioma diagnosis and therapy.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Five new Zn(II)/ODPT/bpe compounds, namely, {Zn(bpe)(H2O)2(H2ODPT)·3H2O} n (1), {Zn4(ODPT)2(bpe)3(H2O)22(bpe)·7H2O} n (2), {Zn2(ODPT)(bpe)22·7H2O} n (3), {Zn4(ODPT)2(bpe)} n (4), and ...{Zn2(ODPT)(bpe)(H2O)2} n (5) (ODPT = 4,4′-oxidiphthalate, bpe =1,2-bis(4-pyridyl)ethane), have been synthesized through a hydrothermal method under different pH conditions, and characterized by single-crystal X-ray diffraction, element analysis, infrared spectra (IR), and thermogravimetric (TG) analyses. Compound 1 shows a 3D network framework constructed by the 1D linear Zn(bpe)(H2O)4 n 2+ cationic chains through extensive hydrogen-bonding. Compound 2 displays an unusual three-dimensional (3D) meso-racemic self-penetrating coordination network with distinct chiral information in the interpenetrating networks. Compound 3 features a novel 4-connected (4·62·83)(42·62·82) topology, also exhibiting an intriguing 3D self-penetrating structure formed by triple- and double-stranded helical chain motifs. Compounds 4 and 5 are based upon 3D pillared-layer frameworks constructed from Zn2+ and ODPT4‑, and further consolidated by the bpe ligands as molecular pillars. The most striking feature of 5 is that achiral ODPT4– ligands link the Zn cations into right-handed 21 helical chains, and the chiral information is transferred to the 3D framework with a chiral space group C2221. The diversity of the product structures illustrates the marked sensitivity of the coordination chemistry of the V-shaped multicarboxylate ligand (H4ODPT) to the pH value of the solution. Moreover, the thermal dynamic properties and fluorescent properties of all compounds are also investigated.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
•Assessment of the thermal performance of microchannel heat sink with nanofluid is studied.•The maximum suppression of the thermal resistance attained by employing the nanofluid is about 12.61%.•The ...maximum enhancement of the nanofluid for the heat transfer coefficient is up to 14.43%.
By increasing demands for high thermal performance and energy efficiency, attentions to microchannel heat sinks (MCHSs) as the suitable method for heat flux dissipation from thermal systems have increased significantly. Microchannel heat sinks can be widely employed in electronic devices for higher heat removal rate and to provide best performance and durability for electronic systems. The critical issue associated with MCHSs is their ability for integration of effective thermal performance. In this work, on the assessment of the thermal performance of microchannel heat sink with nanofluid is experimentally examined. The heat removal performance of the pure water and nanofluid through the MCHS is studied. Different important parameters, such as dimensionless wall temperature, pressure drop, mean convection heat transfer coefficient, thermal resistance, and uniformity index, are investigated. The results indicated that the maximum suppression value of the thermal resistance attained by employing the nanofluid is 12.61%. The uniformity index of the heating surface is increased as the Re number increases. More suppression in the wall temperature can be observed as the volume concentration of nanoparticles is increased. By increasing the total flow rate and using the nanofluid, the hot spots on the heating surface are suppressed. Finally, the maximum gain value of the nanofluid for the mean convection heat transfer coefficient is up to 14.43%.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
Display omitted
Microbial extracellular polymeric substances (EPS) with a high polysaccharides content contribute to membrane fouling in membrane bioreactors. Sodium alginate (Alg) has been widely ...used as a substitute for polysaccharides in EPS to study membrane fouling; however, the rational for such a substitute is unclear and remains to be verified. In this work, the differences in the colloid properties of Alg-Ca2+ and EPS-Ca2+ were explored by integrating rheometry and dynamic light scattering with regard to distinct membrane fouling behaviors. The Alg-Ca2+ exhibited a larger hydrodynamic diameter and higher colloidal stability, which were attributed to its more solidified complexation compared with the electrostatic interactions in EPS-Ca2+. As a result, the gel layer of Alg-Ca2+ that formed on the membrane surface was denser and more impermeable, leading to a faster flux decline in the membrane filtration process. These results indicate that it is questionable to substitute polysaccharides in EPS with Alg for membrane fouling studies. Considering the substantial differences in the colloid properties, it would be better to modify Alg or find a more appropriate substitute for membrane fouling studies.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
Glioma stem cells (GSCs) are responsible for glioma recurrence and drug resistance, yet the mechanisms underlying their maintenance remains unclear. This study aimed to identify enhancer-controlled ...genes involved in GSCs maintenance and elucidate the mechanisms underlying their regulation.
We analyzed RNA-seq data and H3K27ac ChIP-seq data from GSE119776 to identify differentially expressed genes and enhancers, respectively. Gene Ontology analysis was performed for functional enrichment. Transcription factors were predicted using the Toolkit for Cistrome Data Browser. Prognostic analysis and gene expression correlation was conducted using the Chinese Glioma Genome Atlas (CGGA) data. Two GSC cell lines, GSC-A172 and GSC-U138MG, were isolated from A172 and U138MG cell lines. qRT-PCR was used to detect gene transcription levels. ChIP-qPCR was used to detect H3K27ac of enhancers, and binding of E2F4 to target gene enhancers. Western blot was used to analyze protein levels of p-ATR and γH2AX. Sphere formation, limiting dilution and cell growth assays were used to analyze GSCs growth and self-renewal.
We found that upregulated genes in GSCs were associated with ataxia-telangiectasia-mutated-and-Rad3-related kinase (ATR) pathway activation, and that seven enhancer-controlled genes related to ATR pathway activation (LIN9, MCM8, CEP72, POLA1, DBF4, NDE1, and CDKN2C) were identified. Expression of these genes corresponded to poor prognosis in glioma patients. E2F4 was identified as a transcription factor that regulates enhancer-controlled genes related to the ATR pathway activation, with MCM8 having the highest hazard ratio among genes positively correlated with E2F4 expression. E2F4 bound to MCM8 enhancers to promote its transcription. Overexpression of MCM8 partially restored the inhibition of GSCs self-renewal, cell growth, and the ATR pathway activation caused by E2F4 knockdown.
Our study demonstrated that E2F4-mediated enhancer activation of MCM8 promotes the ATR pathway activation and GSCs characteristics. These findings offer promising targets for the development of new therapies for gliomas.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
