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排序方式: 共有263条查询结果,搜索用时 15 毫秒
121.
Mohammad Foad Abazari Shohreh Zare Karizi Mina Kohandani Navid Nasiri Fatemeh Nejati Ehsan Saburi Amin Reza Nikpoor Seyed Ehsan Enderami Fatemeh Soleimanifar Vahid Mansouri 《先进技术聚合物》2020,31(10):2259-2269
Tissue engineering using new strategies has become a growing and promising method for treating large tissue lesions in the body. On the other hand, microRNAs (miRNAs), which are small non‐coding regulatory RNAs, are a new class of genetic materials that can have effective pharmacological roles. The combination of these two themes has created promising prospects for the treatment of diseases. Herein, human induced pluripotent stem cells (iPSCs) were transduced with miRNA‐2861 and then the osteogenic differentiation potential of transduced iPSCs and non‐transduced iPSCs was investigated while cultured on the electrospun poly lactic‐co‐glycolic acid (PLGA) nanofibrous scaffold and culture plate. MiR‐2861‐transduced iPSCs showed a significantly higher viability, mineralization, alkaline phosphatase (ALP) activity, calcium content, and bone‐related gene expression in comparison with those iPSCs that non‐transduced. The results also indicated that this increase is improved when miR‐2861 transduced iPSCs are cultured on the PLGA nanofibrous scaffold synergistically. This synergy was also confirmed by the results obtained from of Western blot analysis. It can be concluded that, miR‐2861, by negative regulation of those proteins that decrease/inhibit osteogenic differentiation and PLGA nanofibrous scaffold by preparation of a suitable artificial extracellular matrix, have a great positive impact in improving iPSCs osteogenic differentiation potential and this blend can be proposed to use in bone tissue engineering application. 相似文献
122.
Sadia Ameen M. Shaheer Akhtar Young Soon Kim O-Bong Yang Hyung-Shik Shin 《Colloid and polymer science》2011,289(4):415-421
The polyaniline/zinc oxide (PANI/ZnO) nanocomposites were prepared by in situ polymerization of aniline monomer with ZnO nanomaterials
and applied as a photocatalyst for the degradation of methylene blue (MB) dye. The morphological observations elicited the
agglomerations of PANI sheets which occurred due to the interaction between PANI and ZnO nanomaterials in PANI/ZnO nanocomposites.
As compared to pristine PANI, the UV–vis spectra exhibited that the absorption peak of π–π* transitions considerably shifted to higher wavelength at 360 nm from 325 nm in the nanocomposites. The photocatalytic activity
results indicated the substantial degradation of MB dye by ~76% over the surface of PANI/ZnO nanocomposite catalyst under
light illumination. The PANI/ZnO nanocomposites showed three times higher photocatalytic activity to MB dye degradation compared
to pristine PANI might due to high photogenerated electron (ē)–hole (h+) pairs charge separation. 相似文献
123.
Dominique Bélanger Xia Tong Sadia Soumaré Yves L. Dory Prof. Yue Zhao Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(17):4428-4436
Pepped up polymers : The synthesis and properties of novel chiral cyclic peptides designed to complex with suitable polymers through hydrogen bonding are described. A substituted cyclic peptide self‐assembles into supramolecular nanotubes and develops noncovalent interactions with poly(vinyl alcohol) (PVA) by means of its carboxyl side chains.
124.
Fawad Ahmad Muneera D. F. Alkahtani Muhammad Babar Taj Afnan M. Alnajeebi Seraj Omar Alzahrani Nouf Abubakr Babteen Walla Alelwani Azzah M. Bannunah Sadia Noor Rabia Ayub Syed Ahmad Tirmizi Heba Alshater 《Molecules (Basel, Switzerland)》2021,26(4)
In the present study, naphthyl acetohydrazide (HL) ligand was prepared and used for the synthesis of new six amorphous transition metal (Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II)) complexes. All the compounds were characterized by elemental analysis, UV-vis, FT-IR, 1H- and 13C-NMR, and Matrix-Assisted Laser Desorption Ionization (MALDI). The solubilization study was carried out by estimating the interaction between the metal complexes with surfactants viz. sodium stearate (SS) and Cetyltrimethylammonium bromide (CTAB). UV-Visible spectroscopy was employed to determine partitioning and binding parameters, whereas electrical conductivity measurements were employed to estimate critical micellar concentration (CMC), the extent of dissociation, and free energy of micellization. The CT-DNA interaction of synthesized compounds with DNA represents the major groove binding. The synthesized ligand and metal complexes were also tested against bacterial and fungal strains and it has been observed that Cu(II) complex is active against all the strains except Candida albicans, while Cd(II) complex is active against all bacterial and fungal strains except Pseudomonas. Among all compounds, only the Pd(II) complex shows reasonable activity against cervical cancer HeLa cell lines, representing 97% inhibition. 相似文献
125.
Fadoua Asraoui Ayoub Kounnoun Francesco Cacciola Fouad El Mansouri Imad Kabach Yassine Oulad El Majdoub Filippo Alibrando Katia Arena Emanuela Trovato Luigi Mondello Adnane Louajri 《Molecules (Basel, Switzerland)》2021,26(11)
Medicinal plants offer imperative sources of innovative chemical substances with important potential therapeutic effects. Among them, the members of the genus Inula have been widely used in traditional medicine for the treatment of several diseases. The present study investigated the antioxidant (DPPH, ABTS and FRAP assays) and the in vitro anti-hyperglycemic potential of aerial parts of Inula viscosa (L.) Aiton (I. viscosa) extracts through the inhibition of digestive enzymes (α-amylase and α-glucosidase), responsible of the digestion of poly and oligosaccharides. The polyphenolic profile of the Inula viscosa (L.) Aiton EtOAc extract was also investigated using HPLC-DAD/ESI-MS analysis, whereas the volatile composition was elucidated by GC-MS. The chemical analysis resulted in the detection of twenty-one polyphenolic compounds, whereas the volatile profile highlighted the occurrence of forty-eight different compounds. Inula viscosa (L.) Aiton presented values as high as 87.2 ± 0.50 mg GAE/g and 78.6 ± 0.55mg CE/g, for gallic acid and catechin, respectively. The EtOAc extract exhibited the higher antioxidant activity compared to methanol and chloroform extracts in different tests with (IC50 = 0.6 ± 0.03 µg/mL; IC50 = 8.6 ± 0.08 µg/mL; 634.8 mg ± 1.45 AAE/g extract) in DPPH, ABTS and FRAP tests. Moreover, Inula viscosa (L.) Aiton leaves did show an important inhibitory effect against α-amylase and α-glucosidase. On the basis of the results achieved, such a species represents a promising traditional medicine, thanks to its remarkable content of functional bioactive compounds, thus opening new prospects for research and innovative phytopharmaceuticals developments. 相似文献
126.
The development and optimization of analytical methods for the better monitoring of disinfection by-products especially haloacetic acids in water are key step in order to estimate human exposure to such products after chlorination. A reliable and accurate analytical method is needed in order to reach the levels of concentration required by United States Environmental Protection Agency regulations. In this study a method was developed for determining halogenated acetic acids in drinking water, involving solid phase extraction, methylation derivatization, and GC-MS. The new SPE-GC-MS-SIM method is capable of analyzing all nine acids at extremely low μg L–1 level. Run time is significantly reduced without compromising analytical results. The major advantages of the method are the simplicity of the chromatography, short run time and low detection limits. The method performance, limits of detection and spiking recovery were evaluated and the results proved that the accuracy and precision were good. This method outperforms previous GC-MS methods especially for the determination of dibromoacetic, dibromochloroacetic, dichlorobromoacetic and tribromoacetic acids. The method has been used to analyse domestic tap water and water samples collected at a local water treatment plant. 相似文献
127.
F. Ghanbari T. Ghoorchi P. Shawrang H. Mansouri N.M. Torbati-Nejad 《Radiation Physics and Chemistry》2012,81(6):672-678
This study was conducted to compare effects of electron beam (EB) and gamma ray (GR) treatments at doses of 25, 50 and 75 kGy on ruminal degradation kinetics of crude protein (CP), amino acid (AA), and in vitro digestibility of cottonseed meal (CSM). Ionizing radiations of EB and GR had significant effects (P<0.05) on CP and AA ruminal degradability characteristics of CSM. Effective ruminal degradability (ERD) of CP was lower in EB and GR irradiated CSM (P<0.05) than in unirradiated CSM. GR and EB treatments had the same effects on ERD decreasing of CP (P>0.05). Irradiation processing caused decrement in AA degradation after 16 h of ruminal incubation (P<0.05). EB irradiation was more effective than GR irradiation in lessening the ruminal degradability of AA (P<0.05). EB and GR treatments at a dose of 75 kGy increased in vitro digestibility of CSM numerically. This study showed that EB could cause CP and AA bypass rumen as well as GR. Therefore, ionizing irradiation processing can be used as an efficient method in improving nutritional value of CSM. 相似文献
128.
Hassan Hadadzadeh Ghobad Mansouri Ali Reza Rezvani Hamid Reza Khavasi 《Journal of chemical crystallography》2012,42(5):486-493
Abstract
The purpose of this study was to investigate whether co-crystals form by simply mixing pure solutions of [Ni(phen)3](PF6)2 and [Ni(phen)2(phen-dione)](PF6)2 where phen is 1,10-phenanthroline and phen-dione is 1,10-phenanthroline-5,6-dione. The 1:1 cocrystal, [Ni(phen)2(phen-dione)][Ni(phen)3](PF6)4·CH3CN has been characterized by elemental analysis, IR, paramagnetic NMR, and UV–vis spectroscopies, cyclic voltammetry, and single crystal X-ray structure analysis. The title complex crystallized in triclinic crystal system (z = 2) with space group of Pī, a = 13.201(2) ?, b = 14.782(3) ?, c = 22.294(4) ?, α = 81.575(15)o, β = 88.756(15)o, γ = 88.032(15)o and V = 4300.1(14) ?3. A careful inspection of the packing pattern in the lattice reveals that non-covalent interactions of three different types, viz. C–H···F, C=O···H−C and C−H···π interactions, are active in the lattice. The coordination around the Ni(II) centers is a distorted octahedral, with bite angles of 78.3−79.8o for the chelating phen and phen-dione ligands. Cyclic voltammetry of this co-crystal shows that the Ni(III/II) couple is quasi-reversible. The effective magnetic moment (μeff) of the co-crystal was measured to be 2.87 BM per Ni(II) ion by Evans method. The magnitude of μeff is consistent with magnetic moment for octahedral Ni(II) complexes. 相似文献129.
A gold nanocage-CNT hybrid for targeted imaging and photothermal destruction of cancer cells 总被引:1,自引:0,他引:1
Khan SA Kanchanapally R Fan Z Beqa L Singh AK Senapati D Ray PC 《Chemical communications (Cambridge, England)》2012,48(53):6711-6713
This communication reports the design of a novel aptamer conjugated gold nanocage decorated SWCNTs hybrid nanomaterial for targeted imaging and selective photothermal destruction of the prostate cancer cells. 相似文献
130.
Special solutions of the LTB family representing collapsing over-dense regions corresponding to asymptotically closed, open,
or flat FRW models are found. These solutions may be considered as representing dynamical mass condensations leading to black
holes immersed in a FRW universe. We study the dynamics of the collapsing region, and its density profile. The question of
the strength of the central singularity and its nakedness, as well as the existence of an apparent horizon and an event horizon
is dealt with in detail, shedding light to the notion of cosmological black holes. Differences to the Schwarzschild black
hole are addressed. 相似文献