Active Fragment of Veronica ciliata

Excessive amounts of reactive oxygen species (ROS) in the body are a key factor in the development of hepatopathies such as hepatitis. The aim of this study was to assess the antioxidation effect in vitro and hepatoprotective activity of the active fragment of Veronica ciliata Fisch. (VCAF). Antioxidant assays (DPPH, superoxide, and hydroxyl radicals scavenging) were conducted, and hepatoprotective effects through the application of tert-butyl hydroperoxide- (t-BHP-) induced oxidative stress injury in HepG2 cells were evaluated. VCAF had high phenolic and flavonoid contents and strong antioxidant activity. From the perspective of hepatoprotection, VCAF exhibited a significant protective effect on t-BHP-induced HepG2 cell injury, as indicated by reductions in cytotoxicity and the levels of ROS, 8-hydroxydeoxyguanosine (8-OHdG), and protein carbonyls. Further study demonstrated that VCAF attenuated the apoptosis of t-BHP-treated HepG2 cells by suppressing the activation of caspase-3 and caspase-8. Moreover, it significantly decreased the levels of ALT and AST, increased the activities of acetyl cholinesterase (AChE), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT), and increased total antioxidative capability (T-AOC). Collectively, we concluded that VCAF may be a considerable candidate for protecting against liver injury owing to its excellent antioxidant and antiapoptosis properties

Interplay between multiple charge-density waves and the relationship with superconductivity in Pdx_xHoTe3_{3}

HoTe$_{3}$, a member of the rare-earth tritelluride ($R$Te$_{3}$) family, and its Pd-intercalated compounds, Pd$_x$HoTe$_{3}$, where superconductivity (SC) sets in as the charge-density wave (CDW) transition is suppressed by the intercalation of a small amount of Pd, are investigated using angle-resolved photoemission spectroscopy (ARPES) and electrical resistivity. Two incommensurate CDWs with perpendicular nesting vectors are observed in HoTe$_{3}$ at low temperatures. With a slight Pd intercalation ($x$ = 0.01), the large CDW gap decreases and the small one increases. The momentum dependence of the gaps along the inner Fermi surface (FS) evolves from orthorhombicity to near tetragonality, manifesting the competition between two CDW orders. At $x$ = 0.02, both CDW gaps decreases with the emergence of SC. Further increasing the content of Pd for $x$ = 0.04 will completely suppress the CDW instabilities and give rise to the maximal SC order. The evolution of the electronic structures and electron-phonon couplings (EPCs) of the multiple CDWs upon Pd intercalation are carefully scrutinized. We discuss the interplay between multiple CDW orders, and the competition between CDW and SC in detail.Comment: 6 pages, 5 figure

Microwave Signal Replicator Design for Testing of the Multi-Channel Transcranial Magnetic Stimulator

The multi-channel transcranial magnetic stimulator is commonly used for rehabilitation treatment of ischemic cerebrovascular disease, neurosis, and brain injury diseases in the elderly. And multiple high coherency signals are required as inputs for its test, which are with consistent frequency, adjustable amplitude, equal magnitude, and long-time phase consistency ⩽±1°. But ordinary signal sources have only one output channel, which is far from meeting the test requirements. If the traditional power division is used for the duplication, the phase difference between the channels will be larger than ±1°. If the multi-throw Radio Frequency (RF) switch is used, it will seriously affect the phase consistency of the input signal and increase the distortion of the signal. In order to solve the above problems, the method to extend the output of the microwave signal source has been proposed in the paper by using the integrated transceiver AD9361. The proposed method can realize the duplication of the number of signal channels according to user requirements. Then a signal replicator has been designed by combining AD9361 chip and Field-Programmable Gate Array (FPGA) control module. The experimental platform has been built to test the performance of the designed device. Experimental results show that the duplicated signals are highly consistent with the source signal in the power amplitude and frequency, meanwhile the phase of the duplicated signals are all highly consistent with each other

A systematic review and meta-analysis of Comaneci/Cascade temporary neck bridging devices for the treatment of intracranial aneurysms

BackgroundThe temporary neck bridging devices represented by Comaneci and Cascade are a type of promising endovascular device for the treatment of intracranial bifurcation or wide-necked aneurysms. This systematic review and meta-analysis aim to assess the efficacy and safety of Comaneci/Cascade devices for the treatment of intracranial aneurysms.MethodsWe performed a systematic literature search on articles in PubMed, Embase, and Web of Science that evaluated the efficacy and safety of Comaneci/Cascade devices for endovascular treatment of intracranial aneurysms, based on the Preferred Reporting Items for Systematic Reviews and Meta Analytics (PRISMA) guideline. We extracted the characteristics and treatment related information of patients included in the study, recorded the rate of technical success, procedural related complications, and angiographic outcomes. The angiographic outcome was evaluated based on Raymond Roy classification, and adequate occlusion was defined as Raymond Ray I + II.ResultsNine studies comprising 253 patients with 255 aneurysms were included. Among them, eight studies were conducted in Europe, one study was conducted in the USA. All these studies were retrospective. 206 aneurysms (80.78%) were ruptured. The vast majority of patients with ruptured aneurysms did not receive antiplatelet therapy. The rate of technical success was 97.1% (95% CI, 94.9 to 99.3%, I2 = 0%). The rate of periprocedural clinical complications was 10.9% (95% CI, 5.4 to 22.1%, I2 = 54%). The rate of complete occlusion (RR1) and adequate occlusion (RR1 + RR2) on immediate angiography after the procedure were 77.7% (95% CI, 72.7 to 83.2%, I2 = 35%) and 98% (95% CI, 95.9 to 100%, I2 = 0%) respectively. The rate of complete occlusion (RR1) and adequate occlusion (RR1 + RR2) on the last follow-up angiography were 81.2% (95% CI, 69.2 to 95.2%, I2 = 81%) and 93.7% (95% CI, 85.6 to 100%, I2 = 69%) respectively, with follow-up range from 3 to 18 months. 22/187 (11.76%) cases of aneurysms progressed during the follow-up period. 39/187 (20.86%) cases of aneurysms received additional treatment during the follow-up period. No fatal complications occurred during the treatment.ConclusionThe Comaneci/Cascade device can be used as an auxiliary treatment for intracranial aneurysms, with a good occlusion effect, but the incidence of complications still needs to be monitored

Inhomogeneous d-wave superconducting state of a doped Mott insulator

Recent scanning tunneling microscope (STM) measurements discovered remarkable electronic inhomogeneity, i.e. nano-scale spatial variations of the local density of states (LDOS) and the superconducting energy gap, in the high-Tc superconductor BSCCO. Based on the experimental findings we conjectured that the inhomogeneity arises from variations in local oxygen doping level and may be generic of doped Mott insulators which behave rather unconventionally in screening the dopant ionic potentials at atomic scales comparable to the short coherence length. Here, we provide theoretical support for this picture. We study a doped Mott insulator within a generalized t-J model, where doping is accompanied by ionic Coulomb potentials centered in the BiO plane. We calculate the LDOS spectrum, the integrated LDOS, and the local superconducting gap, make detailed comparisons to experiments, and find remarkable agreement with the experimental data. We emphasize the unconventional screening in a doped Mott insulator and show that nonlinear screening dominates at nano-meter scales which is the origin of the electronic inhomogeneity. It leads to strong inhomogeneous redistribution of the local hole density and promotes the notion of a local doping concentration. We find that the inhomogeneity structure manifests itself at all energy scales in the STM tunneling differential conductance, and elucidate the similarity and the differences between the data obtained in the constant tunneling current mode and the same data normalized to reflect constant tip-to-sample distance. We also discuss the underdoped case where nonlinear screening of the ionic potential turns the spatial electronic structure into a percolative mixture of patches with smaller pairing gaps embedded in a background with larger gaps to single particle excitations.Comment: 19 pages, final versio

Time-resolved measurements of sub-optical-cycle relativistic electron beams

We propose an all-optical technique to record the time information of relativistic electron beams with sub-optical-cycle duration. The technique is based on the interaction of the electron beam with the ponderomotive potential of an optical traveling wave generated by two counter-propagating circularly polarized optical fields at different frequencies in vacuum. One of the optical pulses is a vortex laser pulse, and the other is a normal Gaussian laser pulse. The time information of the electron beam is mapped into the angular information, which can be converted into a spatial distribution after a drift section. Thus, the temporal profile and arrival time of the electron beam can be retrieved from the spatial distribution of the electron beam. The measurement has a dynamic range comparable to the period of the optical intensity grating formed by two counter-propagating laser pulses. This technique may have wide applications in many research fields that require sub-optical-cycle electron beams

Parabolic Mirror Focusing of Spatiotemporally Coupled Ultrashort Terahertz Pulses

Ultrashort terahertz (THz) beam is often affected by spatio-temporal distortion due to its long wavelength, and this spatio-temporal coupling will degrade the focusing effect. Here, we develop a numerical model for calculating the vector focusing of ultrashort pulses with arbitrary spatial and temporal distribution, which adopt the vector diffraction integral and coherent spectrum superposition methods. Leveraging it, the focusing of a broadband pulse can be characterized together with its vector characteristics and we explore the influences of multifarious spatio-temporal couplings on the focusing of ultrashort THz pulses. In addition, the possibility of focusing the ultrashort THz radiation from an undulator to 1 GV/m is also discussed. This will provide further guidance for the non-equilibrium state of matter induced by ultrashort strong-field THz pulses

T0901317, an Agonist of Liver X Receptors, Attenuates Neuronal Apoptosis in Early Brain Injury after Subarachnoid Hemorrhage in Rats via Liver X Receptors/Interferon Regulatory Factor/P53 Upregulated Modulator of Apoptosis/Dynamin-1-Like Protein Pathway

Background and Purpose. T0901317, a liver X receptor (LXR) agonist, is widely used to explore the functions of LXRs. T0901317 exerts antiapoptotic effects in many central nervous system disease models. Our aim was to detect the role of T0901317 in neuronal apoptosis in early brain injury after subarachnoid hemorrhage. Methods. Subarachnoid hemorrhage (SAH) models of Sprague-Dawley rats were established with perforation method. T0901317 was injected intraperitoneally 1-hour post-SAH. GSK2033, an inhibitor of LXRs, and interferon regulatory factor (IRF-1) CRISPR activation were injected intracerebroventricularly to evaluate potential signaling pathway. The severity of SAH, neurobehavior test in both short- and long-term and apoptosis was measured with Western blot and immunofluorescence staining. Results. Expression of LXR-α and IRF-1 increased and peaked at 24 h post-SAH, while LXR-β remained unaffected in SAH+vehicle group compared with Sham group. Post-SAH T0901317 treatment attenuated neuronal impairments in both short- and long-term and decreased neuronal apoptosis, the expression of IRF-1, P53 upregulated modulator of apoptosis (PUMA), dynamin-1-like protein (Drp1), Bcl-2-associated X protein (Bax) and cleaved caspase-3, and increasing B-cell lymphoma 2 (Bcl-2) at 24 h from modeling. GSK2033 inhibited LXRs and reversed T0901317\u27s neuroprotective effects. IRF-1 CRISPR activation upregulated the expression of IRF-1 and abolished the treatment effects of T0901317. Conclusion. T0901317 attenuated neuronal apoptosis via LXRs/IRF-1/PUMA/Drp1 pathway in SAH rats