Progress of researches on mechanisms of acupuncture underlying improvement of cerebral ischemia-reperfusion injury by regulating calcium overload. / é’ˆåˆºè°ƒæŽ§è„‘ç¼ºè¡€å†çŒæ³¨æŸä¼¤åŽé’™è¶ è½½æœºåˆ¶ç ”ç©¶è¿›å±•.

Ischemic stroke is currently the most common type of stroke, and the key pathological link is cerebral ischemia-reperfusion injury (CIRI), while the key factor leading to apoptosis and necrosis of ischemic nerve cells is calcium overload. Current studies have confirmed that acupuncture therapy has a good modulating effect on calcium homeostasis and can reduce cerebral ischemia-reperfusion induced damage of neuronal cells by inhibiting calcium overload. After reviewing the relevant literature published in the past 15 years, we find that acupuncture plays a role in regulating the pathological mechanism of calcium overload after CIRI by inhibiting the opening of connexin 43 hemichannels, regulating the intracellular free calcium ion concentration, suppressing the expression of calmodulin, and blocking the function of L-type voltage-gated calcium channels, thereby inhibiting calcium overload, regulating calcium homeostasis and antagonizing neuronal damage resulted from cerebral ischemia-reperfusion, which may provide ideas for future research.

Adaptive weighted Gerchberg-Saxton algorithm for generation of phase-only hologram with artifacts suppression.

In the conventional weighted Gerchberg-Saxton (GS) algorithm, the feedback is used to accelerate the convergence. However, it will lead to the iteration divergence. To solve this issue, an adaptive weighted GS algorithm is proposed in this paper. By replacing the conventional feedback with our designed feedback, the convergence can be ensured in the proposed method. Compared with the traditional GS iteration method, the proposed method improves the peak signal-noise ratio of the reconstructed image with 4.8 dB on average. Moreover, an approximate quadratic phase is proposed to suppress the artifacts in optical reconstruction. Therefore, a high-quality image can be reconstructed without the artifacts in our designed Argument Reality device. Both numerical simulations and optical experiments have validated the effectiveness of the proposed method.

Two-dimensional angle multiplexing by segmented spherical holography.

The crosstalk noise produced in the multiplexing technology of curved computer-generated holograms has caused great damage to reconstructed objects. In order to solve this problem, we propose a method to realize three-dimensional object reconstruction with low crosstalk noise impact. By multiplexing the spherical holograms in the horizontal and vertical directions, the complex amplitudes of the multiple spherical holograms with different curvatures are added to form a composed hologram. The generated hologram records many unrelated scenes of the object. According to the different angles used to generate the hologram, the original object under different viewpoints can be rebuilt, and the multiview multiplexing and reconstruction of three-dimensional objects can be realized. Simulation and optical experiments verify the feasibility of this method.

Effects of ensembles on methane hydrate nucleation kinetics.

By performing molecular dynamics simulations to form a hydrate with a methane nano-bubble in liquid water at 250 K and 50 MPa, we report how different ensembles, such as the NPT, NVT, and NVE ensembles, affect the nucleation kinetics of the methane hydrate. The nucleation trajectories are monitored using the face-saturated incomplete cage analysis (FSICA) and the mutually coordinated guest (MCG) order parameter (OP). The nucleation rate and the critical nucleus are obtained using the mean first-passage time (MFPT) method based on the FS cages and the MCG-1 OPs, respectively. The fitting results of MFPT show that hydrate nucleation and growth are coupled together, consistent with the cage adsorption hypothesis which emphasizes that the cage adsorption of methane is a mechanism for both hydrate nucleation and growth. For the three different ensembles, the hydrate nucleation rate is quantitatively ordered as follows: NPT > NVT > NVE, while the sequence of hydrate crystallinity is exactly reversed. However, the largest size of the critical nucleus appears in the NVT ensemble, rather than in the NVE ensemble. These results are helpful for choosing a suitable ensemble when to study hydrate formation via computer simulations, and emphasize the importance of the order degree of the critical nucleus.

Daidzein enhances intramuscular fat deposition and improves meat quality in finishing steers.

An experiment was conducted to determine the effects of soy isoflavone daidzein on carcass characteristics, fat deposition, meat quality, and blood metabolites in finishing steers. Fourteen crossbred steers were used in a 120-d finishing study. These steers were stratified by weight into groups and randomly allotted by group to one of two dietary treatments: (1) control and (2) daidzein (500 mg/kg concentrate). The steers were fed a 90% concentrate diet. Supplemental daidzein did not affect slaughter weight, hot carcass weight, and dressing percentage, but tended to reduce fat proportion (not including intramuscular fat) in carcass and backfat thickness of steers. The carcass bone proportion was greater in steers fed daidzein diets than those fed control diets. Daidzein supplementation reduced pH at 24 h after slaughtered and moisture content and increased isocitrate dehydrogenase activity, fat content (16.28% and 7.94%), marbling score (5.29 and 3.36), redness (a*), and chroma (C*) values in longissimus muscle relative to control treatment. The concentrations of blood metabolites including glucose, blood urea nitrogen, triglyceride, total cholesterol, non-esterified fatty acid, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were all lower in steers fed daidzein diets than those fed control diets. Current results suggest that supplemental daidzein can affect lipid metabolism, increase intramuscular fat content and marbling score, and improve meat quality in finishing steers. Daidzein should be a promising feed additive for production of high-quality beef meat.

Association between polymorphisms and haplotypes of the beta-2 adrenergic receptor gene and asthma in a Chinese Han population.

Conflicting data have been reported on the association of variants of the beta-2 adrenergic receptor (ADRB2) gene with asthma etiology. To provide a scientific basis for the prevention and treatment of asthma, the relationship between single nucleotide polymorphisms and haplotypes of ADRB2 and asthma was examined in a Chinese Han population. Six loci (base positions -2387, -47, 46, 79, 491, and 523) of ADRB2 were examined in a group of individuals with asthma (n = 429) and a control group of individuals who do not have the disease (n = 483). Polymorphisms at the -47 locus [odds ratio (OR) = 0.789, 95% confidence interval (CI): 0.398~0.961, P < 0.05) and the 79 locus (OR = 0.788, 95% CI: 0.394~0.948, P < 0.05) and haplotype III (CCGGC; OR = 0.705, 95% CI: 0.412~0.973, P < 0.05) were correlated with asthma susceptibility and may affect the incidence of asthma in a Chinese Han population by conferring a protective effect. By examining several polymorphisms and haplotypes, this study yields a more comprehensive examination of the role of the ADRB2 gene in the pathogenesis of asthma.

One-step preparation of a water-soluble carbon nanohorn/phthalocyanine hybrid for dual-modality photothermal and photodynamic therapy.

The biomedical applications of carbon nanomaterials, especially integrating noninvasive photothermal therapy (PTT) and photodynamic therapy (PDT), into a single system have enormous potential in cancer therapy. Herein, we present a novel and facile one-step method for the preparation of water-soluble single-walled carbon nanohorns (SWNHs) and metal phthalocyanines (MPc) hybrid for PTT and PDT. The hydrophilic MPc, tetrasulfonic acid tetrasodium salt copper phthalocyanine (TSCuPc), is coated on the surface of SWNHs via noncovalent π-π interaction using the sonication method. In this PTT/PDT nanosystem, SWNHs acts as a photosensitizer carrier and PTT agent, while TSCuPc acts as a hydrophilic and PDT agent. The EPR results demonstrated that the generated reactive oxygen species (ROS) not only from the photoinduced electron transfer process from TSCuPc to SWNHs but also from SWNHs without exciting TSCuPc to its excited state. The test of photothermal conversion proved that not only do SWNHs contribute to the photothermal therapy (PTT) effect, TSCuPc probably also contributes to that when it coats on the surface of SWNHs upon exposure to a 650-nm laser. More importantly, the results of in vitro cell viability revealed a significantly enhanced anticancer efficacy of combined noninvasive PTT/PDT, indicating that the SWNHs-TSCuPc nanohybrid is a hopeful candidate material for developing an efficient and biocompatible nanoplatform for biomedical application.

Using the face-saturated incomplete cage analysis to quantify the cage compositions and cage linking structures of amorphous phase hydrates.

Recent advances in the molecular dynamics simulations of spontaneous nucleation and growth of methane hydrate show that an amorphous phase of the hydrate is first reached. However, the amorphous hydrate has not been well described, due to the insufficient identification of cage structures. Here, we develop a method, called "face-saturated incomplete cage analysis", which can identify all face-saturated cages in a given system. As a result, it is found that thousands of cage types and abundant occupancy states are present in the amorphous hydrate. Moreover, the crystallinity of amorphous hydrate is evaluated according to the quantitative calculation of cage linking structures, and the critical nucleus of hydrate is also estimated on the basis of clustering analysis for all face-saturated cages.

Arsenic trioxide induces the apoptosis in bone marrow mesenchymal stem cells by intracellular calcium signal and caspase-3 pathways.

It was previously reported that excessive arsenic trioxide would produce cardiovascular toxicity. Bone marrow mesenchymal stem cells (BMSCs) have been shown to play a supporting role in cardiovascular functions. The increasing apoptosis of BMSCs commonly would promote the development of cardiovascular diseases. Thus we hypothesize that arsenic trioxide caused apoptosis in BMSCs, which provided a better understanding of arsenic toxicity in hearts. The present study was designed to investigate the proapoptotic effects of arsenic trioxide on BMSCs and explore the mechanism underlying arsenic trioxide-induced BMSCs apoptosis. We demonstrate that arsenic trioxide significantly inhibited survival ratios of BMSCs in a concentration-dependent and time-dependent manner. The Annexin V/PI staining and terminal deoxynucleotidyl transferasemediated dUTP nick-end labelling (TUNEL) assay also showed that arsenic trioxide markedly induced the apoptosis of BMSCs. The caspase-3 activity was obviously enhanced in the presence of arsenic trioxide in a concentration-dependent manner in BMSCs. Additionally, arsenic trioxide caused the increase of intracellular free calcium ([Ca(2+)](i)) in rat BMSCs. BAPTA pretreatment may attenuate the apoptosis of BMSCs induced by arsenic trioxide. Taken together, arsenic trioxide could inhibit the proliferation and induce the apoptosis of BMSCs by modulating intracellular [Ca(2+)](i), and activating the caspase-3 activity.