Background: The growing applications of nanotechnologic products, such as quantum dots (QDs), increase the likelihood of exposure. Furthermore, their accumulation in the bioenvironment and retention ...in cells and tissues are arousing increasing worries about the potentially harmful side effects of these nanotechnologic products. Previous studies concerning QD cytotoxicity focused on the reactive oxygen species produced by QDs. Cellular calcium homeostasis dysregulation caused by QDs may be also responsible for QD cytotoxicity. Meanwhile the interference of QDs with voltage-gated sodium channel (VGSC) current$({\rm I}_{{\rm Na}})$may lead to changes in electrical activity and worsen neurotoxicologic damage. Objective: We aimed to investigate the potential for neurotoxicity of cadmium selenium QDs in a hippocampal neuronal culture model, focusing on cytoplasmic calcium levels and VGSCs function. Methods: We used confocal laser scanning and standard whole-cell patch clamp techniques. Results: We found that a) QDs induced neuron death dose dependently; b) cytoplasmic calcium levels were elevated for an extended period by QD treatment, which was due to both extracellular calcium influx and internal calcium release from endoplasmic reticulum; and c) QD treatment enhanced activation and inactivation of${\rm I}_{{\rm Na}}$, prolonged the time course of activation, slowed${\rm I}_{{\rm Na}}$recovery, and reduced the fraction of available VGSCs. Conclusion: Results in this study provide new insights into QD toxicology and reveal potential risks of their future applications in biology and medicine.
Relaxor ferroelectrics Pb(Sc1/2Nb1/2)O3 (PSN) attracted intensive attention due to its unique properties such as ordering-disordering transition of B/B' cations. In this work, the effect of pH value ...on the PSN powders by the precipitation method was systematically investigated. The experiments show that the formation of perovskite PSN was strongly related to the pH condition, which impacts the chemical stoichiometry of the precipitates and grain morphologies of the PSN powders: at low pH condition, the perovskite PSN was accompanied with the pyrochlore phase due to the deficiency of Pb; however, high pH value resulted in the large size of the powders due to the strong agglomeration effect of OH- wrapping, even though the pure perovskite PSN powders was obtained. The PSN powders precipitated at a mild pH of 8.1 achieved a pure perovskite PSN powders with chemical stoichiometry and grain size of 400nm. Besides, the dielectric measurements of PSN ceramics prepared by precipitation method show the typical relaxor ferroelectrics characteristics, and a more diffusive phase transition than that for PSN ceramics fabricated by conventional solid-state reaction method.
Next-generation neutrino telescopes with significantly improved sensitivity are required to pinpoint the sources of the diffuse astrophysical neutrino flux detected by IceCube and uncover the ...century-old puzzle of cosmic ray origins. A detector near the equator will provide a unique viewpoint of the neutrino sky, complementing IceCube and other neutrino telescopes in the Northern Hemisphere. Here we present results from an expedition to the north-eastern region of the South China Sea, in the western Pacific Ocean. A favorable neutrino telescope site was found on an abyssal plain at a depth of \(\sim\) 3.5km. At depths below 3km, the sea current speed, water absorption and scattering lengths for Cherenkov light, were measured to be \(v_{\mathrm{c}}<\)10cm/s, \(\lambda_{\mathrm{abs} }\simeq\) 27m and \(\lambda_{\mathrm{sca} }\simeq\) 63m, respectively. Accounting for these measurements, we present the design and expected performance of a next-generation neutrino telescope, TRopIcal DEep-sea Neutrino Telescope (TRIDENT). With its advanced photon-detection technology and large dimensions, TRIDENT expects to observe the IceCube steady source candidate NGC 1068 with 5\(\sigma\) significance within 1 year of operation. This level of sensitivity will open a new arena for diagnosing the origin of cosmic rays and probing fundamental physics over astronomical baselines.
In this paper, an intensive theoretical and experimental investigation is conducted on the dispersion-compensating Raman amplification module configured in double-pass geometry. An analytical model ...is developed to study the gain/pump efficiency improvement and the noise performance in a novel double-pass discrete-Raman-amplifier (DCRA) system. This paper demonstrates that the gain and pump efficiency can be improved significantly by using the double-pass configuration and the pump light reflector. The impairments of multipath-interference (MPI) noise due to the Rayleigh scattering and the external reflection are analyzed in order to balance the high gain efficiency and the enhanced MPI noise in the double-pass DCRA. Furthermore, the nonlinear penalty in the DCRA system is investigated and a 10-Gb/s nonreturn-to-zero (NRZ) signal transmission in a 4 /spl times/ 100-km fiber system is simulated. The signal quality and bit-error rate are examined, and the optimization is done with reference to the input signal level and Raman gain; hence, the impact of double-pass DCRA on the dispersion-compensated optical communication systems is explored.
To evaluate the association between LDL-C and ischemic stroke in patients with nonvalvular atrial fibrillation (AF).
A total of 2 470 patients with nonvalvular AF were included in the present study. ...The clinical data and laboratory examination results of the patients in the hospital were collected. The subjects were either divided into the ischemic stroke history (
=560), and non- ischemic stroke history groups (
=1 910), or divided into the low-middle risk (
=566) and high risk groups (
=1 904) based on CHA(2)DS(2) - VASc score.
There were significant differences in the proportion of Han, the ratio of gender, age, hemoglobin, hematocrit, ALT, serum uric acid, HDL-C and LDL-C between the patients with ischemic stroke history and without (all
<0.05). Similarly, there were significant differences in the proportion of Han, the ratio of gender, age, white blood cell count, hemoglobin, hematocrit, platelet count, ALT, albumin, TG and LDL-C between subjects in the low-middle risk group and those in the high risk gr
The C12(α,γ)O16 reaction is one of the most crucial reactions in nuclear astrophysics. The E2 external capture to the O16 ground state (GS) has not been emphasized in previous analyses but may make a ...significant contribution to the C12(α,γ)O16 cross section depending on the value of the GS asymptotic normalization coefficient (ANC). In the present work, we determine this ANC to be 337±45 fm−1/2 through the C12(B11,Li7)O16 reaction using a high-precision magnetic spectrograph. This sheds light on the existing large discrepancy of more than 2 orders of magnitude between the previously reported ANC values. Based on the new ANC, we experimentally constrain the GS external capture and show that through interference with the high energy tail of the 2+ subthreshold state, a substantial enhancement in the GS SE2(300) factor can be obtained (70±7 keV b) compared to that of a recent review (45 keV b), resulting in an increase of the total S factor from 140 to 162 keV b, which is now in good agreement with the value obtained by reproducing supernova nucleosynthesis calculations with the solar-system abundances. This work emphasizes that the external capture contribution for the ground state transition cannot be neglected in future analyses of the C12(α,γ)O16 reaction.
Breast cancer exhibits poor prognosis and high relapse rates following chemotherapy therapeutics. Thus, this study aims to develop effective novel agents regulating the core molecular pathway of ...breast cancer such as Wnt/β-catenin signaling.
The present study screened a novel inhibitor, called "C188", using MTT assay. The molecular formula of C188 is C
H
FN
O
and the molecular weight is 390. Flow cytometry and Western blotting were employed to assess cell cycle arrest after treatment with C188. Wound-healing and transwell assays were applied to measure the cell migration and invasion viability. The regulatory effects of C188 on Wnt/β‑catenin signaling and localization of β‑catenin in the nucleus were investigated by Western blotting and immunofluorescence.
We found that C188 significantly suppressed proliferation and growth in a dose- and time-dependent manner in breast cancer cells, but not in normal breast cells. The inhibitory effect was caused by cell cycle arrest at the G1-phase which is induced by C188 treatment. Additionally, C188 dramatically inhibited cell migration of breast cancer cells in a dose-dependent manner. The migration inhibition was attributed to the suppression of Wnt/β‑catenin signaling and localization of β‑catenin in the nucleus mediated by regulating phosphorylation of β‑catenin and its subsequent stability. Furthermore, the target genes, including
,
, and
, were downregulated due to the decrease of β‑catenin in the nucleus after exposure to C188.
C188 treatment resulted in the downregulation of cyclin D which led to cell cycle arrest at the G1 phase, and the inhibition of cell migration, indicating that C188 may be an effective novel therapeutic candidate as a potential treatment for human breast cancer.
Epicardial adipose tissue (EAT) is considered an important source of bioactive molecules that can influence coronary arteries directly and is related to the concurrent presence of both obstructive ...coronary stenosis and myocardial ischemia independently. Non-alcoholic fatty liver disease (NAFLD) has become an emergent health problem worldwide.
This cross-sectional study aimed to address the relationship between the volume of EAT and NAFLD and other cardiovascular risk factors in the general population.
In this study, we selected a total of 2,238 participants aged at least 40 years from the Jidong community in Tangshan, China. The 64-slice CT was used to survey the volume of EAT and liver ultrasonography was used for the diagnosis of NAFLD. The study cohorts were compared according to EAT volume.
Cardiovascular risk factors, such as coronary artery calcium score, carotid intima-media thickness, NAFLD, and ideal cardiovascular health metrics were also found to be related to EAT. In multivariate logistic regression analysis, NAFLD groups showed significant association with higher EAT volume, after correcting for main cardiovascular disease risk factors (OR 95% CI, 1.407 1.117, 1.773).
Our findings in a general community population provide evidence that EAT is strongly associated with NAFLD and other cardiovascular risk factors.
Abstract
Background
Some researchers have explored the influence of hsCRP on cardiovascular outcomes stratified by BMI in subjects with known CAD. However, it is unclear whether a novel composite ...biomarker, the high-sensitivity C-reactive protein (hsCRP)-to-BMI ratio (CBR), is associated with poor prognosis in patients who underwent percutaneous coronary intervention (PCI).
Aim
We conducted the present study to evaluate the association between the CBR and poor prognosis in CAD patients undergoing percutaneous coronary intervention (PCI).
Methods
A total of 9,810 patients were prospectively included in the present study. All the participants were classified into 3 groups based on their CBR levels: tertile 1 (CBR ≤ 0.04, n = 3,270), tertile 2 (0.04 < CBR ≤ 0.11, n = 3,270) and tertile 3 (CBR > 0.11, n = 3,270). The primary outcome was defined as major adverse cardiovascular and cerebrovascular events (MACCEs), a composite of all-cause mortality, myocardial infarction (MI), stroke, and target vessel revascularization (TVR).
Results
During a mean follow-up of 26.7 months, a total of 1022 MACCEs, 122 all-cause deaths, 392 nonfatal MIs, 156 strokes and 461 TVRs were recorded. The outcomes of Kaplan–Meier analysis showed that the incidences of MACCE and MI increased with high tertiles of the CBR (MACCE: 8.8% vs. 10.3% vs. 12.1%, log-rank P < 0.001; myocardial infarction: 3.3% vs. 4.1% vs. 4.7%, log-rank P = 0.018). Cox regression analysis showed that the CBR was independently associated with long-term MACCEs and MI.
Conclusion
The hsCRP to BMI ratio is independently associated with long-term MACCE and MI in CAD patients undergoing DES implantation.
The transition metal fluorides KMF3 (M = Mn, Co, and Ni) were synthesized through a simple solution route. The crystal structure, morphology and electrical transport property of the resulting ...products were investigated. The compound KMF3 crystallizes in a cubic perovskite structure with space group Pm-3m (No. 221). A crystal structure of KMF3 was refined by the Rietveld method based on the X-ray powder diffraction data. The unit-cell parameters are 4.189 46(4), 4.075 58(4), and 4.025 70(2) for KMnF3, KCoF3 and KNiF3, respectively. A metal–insulator transition was observed in temperature-dependent electrical transport characterization in the temperature range from 250 to 280 K for these three compounds, which is considered to be related to spin-exchange in this kind of material.
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