608 research outputs found
Bromido{dicycloÂhexyl[2′-(dimethylÂamino)biphenyl-2-yl]phosphine-κP}[2-(4,6-dimethylÂpyrimidin-2-yl)ferrocenyl-κ2 C 1,N]palladium(II) dichloroÂmethane solvate
In the title compound, [FePdBr(C5H5)(C11H10N2)(C26H36NP)]·CH2Cl2, the Pd atom displays a distorted square-planar coordination environment. The five-membered metallacycle adopts an envelope conformation with the coordinated cycloÂpentaÂdienyl C atom 0.4222 (4) Å out of plane. The dihedral angle between the pyrimidinyl ring and substituted cycloÂpentaÂdienyl ring is 21.47 (2)°. In the crystal structure, the dimeric unit is generated through the C—H⋯π contact via a crystallographic inversion centre, while the C—H⋯Cl contacts in the dimeric centre link the dichlormethane molÂecules with the Pd complex molÂecules
Bimodal Fluorescence and Magnetic Resonance Imaging Using Water-Soluble Hexagonal NaYF 4
The present study explored the
feasibility of using hexagonal-phase
NaYF4:Ce,Tb,Gd nanocrystals as bimodal
probes for fluorescence and magnetic resonance
(MR) imaging. Using a facile and user-friendly
strategy, the NaYF4:Ce,Tb,Gd
nanocrystals were synthesized with good water
dispensability, high quantum yield (26%), and
decent MR T1 relaxivity (r1=2.87 mM−1 s−1).
The NaYF4:Ce,Tb,Gd NCs conjugated
by folic acid presented great efficiency in
fluorescence imaging of C6 glioma cells
in vitro. Meanwhile,
in in vivo MR experiments on
rats, the NaYF4:Ce,Tb,Gd NCs also
significantly increased T1 signal in the liver, spleen, and
kidney even with a low probe dose. The
proposed NaYF4:Ce,Tb,Gd nanoprobes
hold promise for simultaneous bimodal
fluorescence and MR bioimaging
Paeoniflorin Ameliorates Macrophage Infiltration and Activation by Inhibiting the TLR4 Signaling Pathway in Diabetic Nephropathy
Paeoniflorin (PF) is the primary component of total glucosides of paeony (TGP). It exerts multiple effects, including immunoregulatory and anti-inflammatory effects. Our previous study has found that PF has a remarkable renal-protective effect in diabetic mice, but exact mechanism has not been clarified. This study mainly explores whether PF affects macrophage infiltration and activation in diabetic kidney through TLR4 pathway. Thus, this study was conducted to investigate the effect of PF on a streptozotocin (STZ)-induced experimental DN model. The results suggested that the onset and clinical symptoms of DN in mice were remarkably ameliorated after the administration of PF. Moreover, the number of infiltrating macrophages in the mouse kidneys was also markedly decreased. Instead of inhibiting the activation of macrophages directly, PF could influence macrophages by suppressing iNOS expression as well as the production of TNF-α, IL-1β, and MCP-1 both in vivo and in vitro. These effects might be attributable to the inhibition of the TLR4 signaling pathway. The percentage of M1-phenotype cells as well as the mRNA levels of iNOS, TNF-α, IL-1β, and MCP-1 were downregulated when PF-treated polarized macrophages were cultured under conditions of high glucose (HG) levels. In addition, the expression of TLR4, along with that of downstream signaling molecule proteins, was also reduced. Our study has provided new insights into the potential of PF as a promising therapeutic agent for treating DN and has illustrated the underlying mechanism of PF from a new perspective
Observation of room-temperature ferroelectricity in elemental Te nanowires
Ferroelectrics are essential in low-dimensional memory devices for multi-bit
storage and high-density integration. A polar structure is a necessary premise
for ferroelectricity, mainly existing in compounds. However, it is usually rare
in elemental materials, causing a lack of spontaneous electric polarization.
Here, we report an unexpected room-temperature ferroelectricity in few-chain Te
nanowires. Out-of-plane ferroelectric loops and domain reversal are observed by
piezoresponse force microscopy. Through density functional theory, we attribute
the ferroelectricity to the ion-displacement created by the interlayer
interaction between lone pair electrons. Ferroelectric polarization can induce
a strong field effect on the transport along the Te chain, supporting a
self-gated field-effect transistor. It enables a nonvolatile memory with high
in-plane mobility, zero supply voltage, multilevel resistive states, and a high
on/off ratio. Our work provides new opportunities for elemental ferroelectrics
with polar structures and paves a way towards applications such as low-power
dissipation electronics and computing-in-memory devices
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