311 research outputs found
(DimethÂoxyÂphosphorÂyl)(furan-2-yl)methyl 2-(2,4-dichloroÂphenÂoxy)acetate
In the title compound, C15H15Cl2O7P, the benzene and furan rings form a dihedral angle of 73.54 (1)°. In the crystal, weak interÂmolecular C—H⋯O hydrogen bonds link the molÂecules into layers parallel to (100)
In vitro cytotoxicity of biosynthesized titanium dioxide nanoparticles in human prostate cancer cell lines
Purpose: To establish a green method for production of titanium dioxide (TiO2) nanoparticles (NPs) using Cinnamomum tamala (C. tamala) leaf extract, and examine the in vitro cytotoxicity of the product in a human prostate cancer (D145) cell line. Methods: TiO2 NPs were synthesized by mixing 20 mL of C. tamala leaf extract with 0.1 M titanium dioxide (Ti(OH)2) (80 mL) in aqueous solution with stirring for 2 h at room temperature. The TiO2 NPs were characterized using x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), x-ray photoelectron spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), selected-area electron diffraction, and energy dispersive x-ray spectroscopy. The in vitro cytotoxicity against D145 cells was determined using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. Results: TEM and DLS analyses showed that the NPs were irregularly shaped, with an average particle size of 23 nm. The FT-IR spectrum of C. tamala leaf extract showed that the biomolecules were potentially involved in reduction processes. The negative zeta potential of -14 mV indicated that the NPs were stable and discrete while their crystalline nature was confirmed by XRD. Cytotoxicity analysis showed that the TiO2 NPs exhibit a dose-dependent toxic effect on D145 cells. Conclusion: A facile and less expensive approach for the production of TiO2 NPs using C. tamala leaf extract has been developed. The TiO2 NPs showed dose-dependent cytotoxicity towards D145 cells. Keywords: Anticancer activity, Cinnamomum tamala, Green synthesis, Prostate cancer, TiO2 nanoparticle
Presurgical thalamic hubness predicts surgical outcome in temporal lobe epilepsy.
OBJECTIVE: To characterize the presurgical brain functional architecture presented in patients with temporal lobe epilepsy (TLE) using graph theoretical measures of resting-state fMRI data and to test its association with surgical outcome.
METHODS: Fifty-six unilateral patients with TLE, who subsequently underwent anterior temporal lobectomy and were classified as obtaining a seizure-free (Engel class I, n = 35) vs not seizure-free (Engel classes II-IV, n = 21) outcome at 1 year after surgery, and 28 matched healthy controls were enrolled. On the basis of their presurgical resting-state functional connectivity, network properties, including nodal hubness (importance of a node to the network; degree, betweenness, and eigenvector centralities) and integration (global efficiency), were estimated and compared across our experimental groups. Cross-validations with support vector machine (SVM) were used to examine whether selective nodal hubness exceeded standard clinical characteristics in outcome prediction.
RESULTS: Compared to the seizure-free patients and healthy controls, the not seizure-free patients displayed a specific increase in nodal hubness (degree and eigenvector centralities) involving both the ipsilateral and contralateral thalami, contributed by an increase in the number of connections to regions distributed mostly in the contralateral hemisphere. Simulating removal of thalamus reduced network integration more dramatically in not seizure-free patients. Lastly, SVM models built on these thalamic hubness measures produced 76% prediction accuracy, while models built with standard clinical variables yielded only 58% accuracy (both were cross-validated).
CONCLUSIONS: A thalamic network associated with seizure recurrence may already be established presurgically. Thalamic hubness can serve as a potential biomarker of surgical outcome, outperforming the clinical characteristics commonly used in epilepsy surgery centers
Scanning tunneling microscopy and spectroscopy of nanoscale twisted bilayer graphene
Nanoscale twisted bilayer graphene (TBG) is quite instable and will change
its structure to Bernal (or AB-stacking) bilayer with a much lower energy.
Therefore, the lack of nanoscale TBG makes its electronic properties not
accessible in experiment up to now. In this work, a special confined TBG is
obtained in the overlaid area of two continuous misoriented graphene sheets.
The width of the confined region of the TBG changes gradually from about 22 nm
to 0 nm. By using scanning tunnelling microscopy, we studied carefully the
structure and the electronic properties of the nanoscale TBG. Our results
indicate that the low-energy electronic properties, including twist-induced van
Hove singularities (VHSs) and spatial modulation of local density-of-state, are
strongly affected by the translational symmetry breaking of the nanoscale TBG.
Whereas, the electronic properties above the energy of the VHSs are almost not
influenced by the quantum confinement even when the width of the TBG is reduced
to only a single moire spot.Comment: 4 Figure
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