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This study was designed to explore cryptanshinone (CPT) extract of Salvia miltiorrhiza stimulating pediatric acute myeloid leukemia (AML) stem cell (LSC) apoptosis and anti-inflammatory mechanism via accelerating microRNA (miR)-211-5p to restrain Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway activation. Obtaining blood samples from pediatric acute myeloid leukemia patients and healthy volunteers and detecting miR-211-5p and JAK2 were performed. Purchase of the human AML cell line KG1a was conducted, and sorting of KG1a cells was to gain LSC. Test of miR-211-5p and JAK2, the phosphorylation of JAK2/STAT3 was implemented. Pretreatment of LSCs was with CPT. Variation of miR-211-5p and JAK2 in LSCs was via plasmid transfection to explore their actions in cell advancement with apoptosis and inflammation. Identification of the targeting of miR-211-5p with JAK2 was implemented. In results: MiR-211-5p was declined in endometrial cancer, while JAK2 was elevated; CPT was available to boost LSC apoptosis and restrain the inflammation; elevated miR-211-5p or repressive JAK2 was available to strengthen the acceleration of CPT on LSCs apoptosis and the repression of inflammation; MiR-211-5p targeted JAK2; augmented JAK2 was available to turn around the action of elevated miR-211-5p. We conclude that CPT extract of Salvia miltiorrhiza stimulated pediatric LSC apoptosis and restrained the inflammation via accelerating microRNA (miR)-211-5p to suppress JAK2/STAT3 pathway activation. [ABSTRACT FROM AUTHOR]

A novel characterization method is introduced to measure Seebeck coefficients on individual Si nanowires (Si NWs). By using conductive atomic force microscopy with slight modifications, without any need of microfabricated devices, the Seebeck coefficients can be conveniently measured on individual Si NWs inside a large-sized vertical array in addition to the measurements on bulk substrates. The results show that the Seebeck coefficients of Si NWs are much larger than their bulk counterparts over a wide temperature range. The temperature dependence of the Seebeck coefficients of Si NWs is found to be entirely different from that of bulk Si, yet both of them agree well with the results obtained by a macroscopic method. Particularly, with this method, the Seebeck coefficients can be easily characterized on Si NWs with varied morphology, size, or doping. As an example, the Seebeck coefficients are measured on Si NWs with different lengths, and it is found that the Seebeck coefficients decrease obviously as the nanowire length increases for all measurement temperatures but the difference becomes smaller at higher temperatures. Overall, this study provides a simple but effective novel method to measure the Seebeck coefficients on individual Si NWs, which has unique advantages on exploring the size or other parameter dependence or revealing the dominant factors in thermoelectric property studies on single nanostructures. [ABSTRACT FROM AUTHOR]

Abstract The effect of the extracts of Epimedium brevicornum Maxim. was investigated on proliferative activity in vitro. The osteoblast-like UMR106 cells was employed as an osteoblast model. The EtOH extract [...]

OBJECTIVE: To explore the effect of carbachol on myocardial injury in septic rats, and to further study its influence on the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. MATERIALS AND METHODS: A total of 48 healthy male Sprague-Dawley rats were randomly divided into sham group (n=16), model group (n=16), and carbachol group (n=16). The rat model of sepsis was established via cecal ligation and puncture. Carbachol was intraperitoneally injected (10 µg/kg) immediately after operation in carbachol group, and no cecal ligation was performed in sham group. At 48 h after operation, the survival rate of rats in each group was recorded, the activity of plasma creatine kinase- MB (CK-MB) was detected, and the cardiac function in each group was determined. Moreover, the heart was isolated, and the myocardial tissues were taken to detect the apoptosis level using the terminal deoxynucleotidyl transferase- mediated dUTP nick end labeling (TUNEL) apoptosis kit. The content of inflammatory factors in myocardial tissues was determined using enzyme-linked immunosorbent assay (ELISA) kits, and the expression levels of apoptosis- related proteins and the PI3K/AKT signaling pathway-related proteins were detected via Western blotting. RESULTS: Carbachol could significantly raise the survival rate of septic rats (p<0.01), remarkably decrease the activity of CK-MB (p<0.01), markedly reduce the left ventricular internal diameter at end-systole (LVIDs), and markedly increase the left ventricular ejection fraction (LVEF, %) and left ventricular fractional shortening (LVFS, %). Besides, carbachol could evidently lower the apoptosis level of myocardial cells of septic rats (p<0.01), reduce the content of inflammatory factors including tumor necrosis factor-a (TNF-a), interleukin-1ß (IL-1ß) and IL-6 (p<0.01), notably decrease the expression of Caspase-3 in myocardial tissues (p<0.01), remarkably increase the expression of Bcl-2/Bax (p<0.01), and distinctly inhibit the expressions of phosphorylated (p-)PI3K, p-AKT, Nodlike receptor protein 3 (NLRP3), and Caspase-1 (p<0.01). CONCLUSIONS: Carbachol can reduce the release of inflammatory factors in myocardial cells, the expression of apoptotic proteins and the apoptosis of myocardial cells, and improve the cardiac function and survival rate of septic rats by inhibiting the PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]

The magnetic properties of SiO2/Fe/SiO2 nanocomposite films are studied by magnetic force microscopy and vibrating sample magnetometer. The films were fabricated by alternately depositing SiO2, Fe, and SiO2 on Si substrates with magnetron sputtering followed by thermal annealing. It is found that the annealing atmosphere significantly influences the sample structure, composition, and magnetic properties. The samples annealed in forming gas show much better magnetic properties than those annealed in vacuum and in N2. The saturation magnetization can reach 200 emu/g, fairly close to the value of bulk Fe, and the coercivity can reach 400 Oe, much higher than 10 Oe of the bulk Fe. X-ray photoelectron spectroscopic depth profile measurement was carried out to study the mechanism of the strong influence of annealing atmosphere. For the samples annealed in forming gas, Fe nanoparticles are mildly oxidized, forming thin shells of Fe2O3 surrounding them, which is beneficial for maintaining the ferromagnetic behavior and enhancing the coercivity of nanoparticles. [ABSTRACT FROM AUTHOR]

Coherently strained GeSi/Si(001) islands were overgrown with a Si capping layer of different thicknesses at temperature 300 °C. The structures of the islands and the Si capping layer were investigated by high resolution transmission electron microscopy. The shapes of the embedded islands were well preserved, whereas planar defects were observed exactly over the islands in the capping layers. The strain energy in regions over the islands accumulated with increasing thickness of the Si capping layer, resulting in the formation of the planar defects. By means of a two-step deposition in which 20-nm-thick Si capping layer was first deposited at a low temperature of 300 °C followed by 70-nm-thick Si capping layer deposition at a high temperature of 640 °C, the defect-free Si capping layer with flat surface can be obtained. [ABSTRACT FROM AUTHOR]

The transverse laser-induced thermoelectric voltages in the tilted La2-xSrxCuO4 (LSCO) thin films are observed for the first time. The detected signals are demonstrated to originate from the anisotropy of thermoelectric power and depend on the Sr-doping level drastically. The largest voltage is observed in the LSCO films at x=0.15 under the irradiation of different lasers with the wavelength in the spectrum range from infrared to ultraviolet. The dependence of the signals on Sr-doping content is associated with a two dimensional charge transport behavior in LSCO films near the optimum doping content. [ABSTRACT FROM AUTHOR]

The dependences of intersubband transitions on well width and nitrogen (N) content in n-type In0.23Ga0.77As1-xNx/GaAs quantum wells (QWs) are investigated using a ten-band k·p model. The absorption peak energy is found to increase first with the well width starting from 2 nm. It becomes insensitive from about 2.5 to 4.5 nm although the absorption intensity increases and bandwidth decreases monotonically, and then keeps decreasing with the well width beyond 4.5 nm. The peak energy is much larger than that of the N-free structure for narrower wells, but the difference decreases quickly with increasing well width. In the case of wider wells, the absorption peak energy shows relatively slow monotonic increase with increasing N content up to 3% because of the N-band and conduction-band coupling. In the nearly lattice-matched GaAsN/AlGaAs QWs the absorption peak energy shows a redshift with increasing N content from 0% to 0.4% and then increases gradually. The theoretical results are consistent with the reported experimental data. [ABSTRACT FROM AUTHOR]

The shape of the self-assembled GeSi/Si(001) islands changed from a dome to a pyramid bounded with {103} or {105} facets after initial Si capping at 640 °C. The strains in the islands with initial Si capping are investigated by Raman spectroscopy. Compared with those of the uncapped islands, both peaks of Ge-Ge and Ge-Si vibration modes in the capped islands show blueshifts, corresponding to the Ge content decrease and the compressive strain increase in the capped islands. The total strain energy in an island is found to increase remarkably after Si capping. After simple analysis, it is found that the surface energy change could not overwhelm this large strain energy increase, making the shape transition favorable. It implies that the strain energy in the substrate in association with an island formation as well as evolution should be considered in accounting for the resulting island shape changes after Si capping. [ABSTRACT FROM AUTHOR]

We present Raman scattering by optical phonons in self-assembled Ge quantum dot superlattices grown by solid-source molecular beam epitaxy. The Ge quantum dots are vertically correlated and have different average sizes and dot morphologies. The GeGe optical phonon frequency was mainly caused by strain relaxation effects. Experimentally observed GeGe optical phonon modes were compared with calculated values using the deformation potential theory, indicating that the strain relaxation of Ge quantum dot superlattices arises not only from atomic intermixing but also from the morphology transition in dot formation. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the efficacy of transesophageal echocardiography (TEE) in the treatment of nonvalvular atrial fibrillation with left atrial appendage (LAA) occlusion. PATIENTS AND METHODS: Forty-nine patients with nonvalvular atrial fibrillation were selected from January 2015 to December 2015 to serve as control group, and 49 patients with nonvalvular atrial fibrillation were selected from January 2016 to December 2016 to serve as observation group. Patients in both groups were treated with LAA occlusion. After surgery, patients in control group received 2D-transesophageal echocardiography (2D-TEE), while patients in observation group received 3D-TEE. LAA diameter, maximum depth, postoperative parameters, and postoperative complications were compared between two groups. RESULTS: The maximum LAA diameter can be measured from different angles in control group, and maximum depth cannot be measured in control group. No significant differences in maximum LAA diameter and maximum depth were found between two groups from different angles (p<0.05). No significant difference in left ventricular end diastolic diameter (LVEDd), left atrial diameter (LA-d), left ventricular ejection fraction (LVEF), mitral regurgitation volume (MV Reg V), E peak and pulmonary vein diastolic flow velocity (PVd) were found between those two groups (p<0.05). The overall occurrence of postoperative complications in observation group and control group were 0.00% and 12.24%, respectively, significant difference was found between those two groups (p<0.05). CONCLUSIONS: Compared with 2D-TEE, the application of 3D-TEE in treatment of nonvalvular atrial fibrillation with left atrial appendage occlusion is more conducive to the selection of the size of the reservoir, and can reduce the occurrence of postoperative complications. [ABSTRACT FROM AUTHOR]

SnO2 nanowires were prepared in an Au-catalyzed VLS growth process by thermal evaporation. The NO sensing properties of the resistive gas sensor based on the SnO2 nanowires was found to be improved obviously after the SnO2 nanowires were treated by Ar-O2 plasma. The responses of the gas sensors to 10, 20, 30, 40, 50 ppm NO gas increased from 8.4, 10.6, 12.6, 14.2, 16.1% to 44.2, 91.9, 108.0, 118.1, 157.4% at 100 °C, respectively. The selectivity of the gas sensors to NO gas against NO2, NH3, CH4, H2 and O2 was also enhanced greatly. The characterization by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy revealed that the enhanced gas sensing properties can be attributed to the rough surfaces, the resultant dangling bond and free lattice sites, and the Sn3O4 grains appearing on the surface of the Ar-O2 plasma treated SnO2 nanowires. [ABSTRACT FROM AUTHOR]

OBJECTIVE: MicroRNAs (miRNAs/ miRs) are small noncoding RNAs that primarily function in RNA silencing and gene regulation at the posttranscriptional level in animals, plants and certain viruses. They have been reported to play a vital role in development and progression of diseases such as cancer. The present study was undertaken to establish a correlation between a specific miRNA in this cluster, termed miR92a, and its association with nonsmall cell lung cancer (NSCLC). MATERIALS AND METHODS: Total RNA was isolated from the plasma using an RNeasy mini kit and cDNA was synthesized by TaqMan MicroRNA Reverse Transcription kit. The expression of miR-92a was quantified by quantitative Real-time PCR (RT-PCR). All transfections were performed using Lipofectamine 2000. Digoxigenin (DIG)labeled locked nucleic acid (LNA) modified probes for miR92a and negative control oligonucleotides were used for in vitro hybridization following manufacturers protocol. Digoxigenin (DIG)labeled locked nucleic acid (LNA)modified probes for miR92a and negative control oligonucleotides (miRCURY LNA MicroRNA Detection Probes; Exiqon, Vedbaek, Denmark) were used. Cell proliferation was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) MTT assay. RESULTS: It was observed that miR92a is highly expressed in NSCLC compared with adjacent tissue samples and plasma from healthy donors. Additionally, the proliferation of three NSCLCderived cell lines, SPCA1, A549 and H2170, was enhanced by miR92a and inhibited by a complementary antimiR92a oligonucleotide sequence. Although the underlying mechanisms of reduced cellular proliferation in the presence of miR92a antagomirs cannot be explained from the current results. CONCLUSIONS: The upregulation of miR92a expression, in cells and plasma, is manifested during the development of NSCLC. [ABSTRACT FROM AUTHOR]

Detailed numerical analysis and computer simulation of a two-dimensional defective photonic crystal structure fabricated with nonlinear optical materials are carried out. The localized states in the band gap and electric field distributions of such a structure were calculated by the finite-difference time-domain method, and demonstrated a greatly enhanced second harmonic generation with an efficiency of about 4 orders of magnitude higher than that in an ordinary nonlinear crystal. [ABSTRACT FROM AUTHOR]

The Ge/Si interdiffusion in GeSi dots grown on Si (001) substrate by gas-source molecular beam epitaxy is investigated. Transmission electron microscopy images show that, after annealing, the aspect ratio of the height to base diameter increases. Raman spectra show that the Si–Ge mode redshifts and the intensity of the local Si–Si mode increases with the increase of annealing temperature, which suggests the Ge/Si interdiffusion during annealing. The photoluminescence peaks from the dots and the wetting layers show blueshift due to the atomic intermixing during annealing. The interdiffusion thermal activation energies of GeSi dots and the wetting layers are 2.16 and 2.28 eV, respectively. The interdiffusion coefficient of the dots is about 40 times higher than that of wetting layers and the reasons were discussed. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Sepsis, a systemic inflammatory response syndrome caused by infection, is a serious threat to the lives of patients. Sepsis can cause tissue hypoperfusion and septic shock which leads to organ dysfunction and death via a variety of mechanisms. Mitochondrial protein (UCP2) involves in immune response, regulation of oxidative stress, and maintenance of mitochondrial membrane potential as well as energy production. However, the role of UCP2 in sepsis remains to be further explored. PATIENTS AND METHODS: A total of 156 patients with sepsis from our hospital were included in this study (69 patients with sepsis and 87 patients with severe sepsis). A total of 69 healthy volunteers were included as controls. Levels of UCP2 in blood cells before and after treatment were measured using RT-PCR and Western blot. The correlation between levels of UCP2 and sepsis was analyzed. RESULTS: The level of UCPPC2 in blood cells of sepsis patients was significantly higher than that of healthy controls at both mRNA level and protein level. The expression level of UCP2 in blood cells of sepsis patients was significantly reduced after treatment, compared to that before treatment. No significant difference was found in the level of UCP2 in blood cells of healthy controls before and after treatment ((p=0.45). Also, the level of UCP2 in blood cells of patients with severe sepsis was significantly higher than that of patients with sepsis at the protein level (p<0.05). Moreover, a positive correlation was found between the level of UCP2 protein and the severity of sepsis. CONCLUSIONS: UCP2 in blood cells might be a specific biomarker for sepsis and the level of UCP2 is positively correlated with the severity of sepsis. [ABSTRACT FROM AUTHOR]