Inhibition of hsa_circ_0003489 shifts balance from autophagy to apoptosis and sensitizes multiple myeloma cells to bortezomib via miR-874-3p/HDAC1 axis.

BACKGROUND: Circular RNAs (circRNAs) crucially regulate tumor progression. In this study, we examined the functional roles and mechanisms of hsa_circ_0003489 in multiple myeloma (MM). METHODS: Upon altering the expressions of hsa_circ_0003489, miR-874-3p, and/or histone deacetylase 1 (HDAC1) in MM1.R cells and treating them with bortezomib (BTZ), cell viability was examined by CCK-8 assay; cell proliferation by Ki-67 immunofluorescence; apoptosis by TUNEL staining, flow cytometry, and western blot; and autophagy by electron microscopy and western blot. The interaction between hsa_circ_0003489 and miR-874-3p as well as that between miR-874-3p and HDAC1 was examined by expressional analysis, dual luciferase reporter assay, and RNA immunoprecipitation. The in vivo impacts of hsa_circ_0003489 on MM growth and sensitivity to BTZ were examined using an MM xenograft mouse model. RESULTS: Knocking down hsa_circ_0003489 significantly inhibited the viability, cell proliferation, and autophagy, while promoting the apoptosis of MM cells in vitro and MM xenograft in vivo. Suppressing hsa_circ_0003489 also further boosted the cytotoxic effects of BTZ in MM cells and reversed its promoting effect on autophagy. Mechanically, hsa_circ_0003489 acted as a sponge of miR-874-3p and positively regulated the expression of miR-874-3p target, HDAC1. MiR-874-3p and HDAC1 essentially mediated the effects of hsa_circ_0003489 on cell viability, proliferation, apoptosis, and autophagy. CONCLUSION: The hsa_circ_0003489/miR-874-3p/HDAC1 axis critically regulates the balance between apoptosis and autophagy. Silencing hsa_circ_0003489 sensitizes MM cells to BTZ by inhibiting autophagy and thus may boost the therapeutic effects of BTZ.

Mechanical Properties Study of Fe-Mn-Si Shape Memory Alloys Welding Seam Formed by Laser Welding with Filler Powder.

To reduce the residual stress and improve the fatigue property of the laser weldment by using the stress self-accommodation characteristic of Fe-Mn-Si shape memory alloys (SMAs), a Fe15Mn5Si12Cr6Ni memory alloy welding seam was formed inside 304 stainless steel by laser welding with filler powder. The combination of the hole-drilling method and the ANSYS software was used to research the distribution law of residual stress inside the laser welding specimen. The fatigue strength of the laser welded specimens with the Fe-Mn-Si SMAs welding seam (experimental materials) and 304 stainless steel welding seam (comparative materials) was measured by cycle bending fatigue test. The microhardness of the welding specimens was measured by the microhardness tester. The thermodynamic model of the laser welding process and the phase transition crystallography of Fe-Mn-Si SMAs were evaluated to analyze the strengthening mechanism of the mechanical properties in the experimental materials. The results show that the distribution law for residual stress in the experiment and simulation are consistent. The experimental materials possess low residual stress, high fatigue strength and high microhardness. The strengthening mechanism for mechanical properties is the welding residual stress-induced γ→ε martensitic transformation inside the experimental materials, which causes the tensile plastic strain of the welding seam to resist residual compression strain, and the residual stress, as the transition driving force, is released in shear processing.

[Dendritic Cells Promote the Proliferation of Peripheral Blood CRTH2 Cells (CD4(+)CD294(+)Th2) and Help B Cells to Secrete Immunoglobulin].

Objective：To investigate the promotive effect of dendritic cells(DCs) on proliferation of CRTH2 (CD4(+)CD294(+)Th2) cells and the influence of CRTH2 cells on secretion of immunoglobulin from B cells so as to provide a new approach for amplification and sorting of Th2 cells. Methods：DCs were induced from peripheral blood mononuclear cells, then the loaded-BCGV-Ag-DCs were cocultured with T cells, and the mixed lymphocyte reaction(MLR) was performed by CCK8 method. The phenotypes of DCs and CRTH2 cells were detected by flow cytometry. CRTH2 cells sorted by MACS were co-cultured with B cells for 5 days to detect the secretion of immunoglobulin. Results：The subsets and absolute number CRTH2 cells were significantly increased by loaded-BCGV-Ag-DCs. The levels of IgG, IgA and IgE were higher increased in supernatant of CRTH2 and B cell co-culture system than that in control group or that in transwell group(P<0.05). Conclusion：The proliferation of CRTH2 cells can be greatly promoted by loaded-BCGV-Ag-DCs, and the CRTH2 cells can help B cells to secrete IgG, IgA and IgE.

Dendritic Cells Promote the Proliferation of Peripheral Blood CRTH2 Cells (CD4(+)CD294(+)Th2) and Help B Cells to Secrete Immunoglobulin / 中国实验血液学杂志

Objective：To investigate the promotive effect of dendritic cells(DCs) on proliferation of CRTH2 (CD4(+)CD294(+)Th2) cells and the influence of CRTH2 cells on secretion of immunoglobulin from B cells so as to provide a new approach for amplification and sorting of Th2 cells. Methods：DCs were induced from peripheral blood mononuclear cells, then the loaded-BCGV-Ag-DCs were cocultured with T cells, and the mixed lymphocyte reaction(MLR) was performed by CCK8 method. The phenotypes of DCs and CRTH2 cells were detected by flow cytometry. CRTH2 cells sorted by MACS were co-cultured with B cells for 5 days to detect the secretion of immunoglobulin. Results：The subsets and absolute number CRTH2 cells were significantly increased by loaded-BCGV-Ag-DCs. The levels of IgG, IgA and IgE were higher increased in supernatant of CRTH2 and B cell co-culture system than that in control group or that in transwell group(P<0.05). Conclusion：The proliferation of CRTH2 cells can be greatly promoted by loaded-BCGV-Ag-DCs, and the CRTH2 cells can help B cells to secrete IgG, IgA and IgE.

Antioxidant phenolic profile from ethyl acetate fraction of Fructus Ligustri Lucidi with protection against hydrogen peroxide-induced oxidative damage in SH-SY5Y cells.

In this study, we demonstrated the antioxidant and protective properties of crude extract and fractions from Fructus Ligustri Lucidi (FLL) against hydrogen peroxide (H2O2)-induced oxidative damage in SH-SY5Y cells. The contents of their phytochemical profiles were determined by spectrophotometric methods and high performance liquid chromatography using a photodiode array detector. FLL crude extract possessed appreciable scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl and H2O2. The ethyl acetate (EtOAc) fraction was the most active fraction in scavenging free radicals and H2O2. Following exposure of cells to H2O2, there was a marked decrease in cell survival and intracellular antioxidant enzymes, and then intracellular oxidative stress, the level of lipid peroxidation, and caspase-3 activity were increased. Simultaneous treatment with the EtOAc fraction blocked these H2O2-induced cellular events. Hydroxytyrosol and salidroside are major components of the EtOAc fraction. These results show that the phenolic-enriched EtOAc fraction of FLL contains tyrosol-related derivatives and exerts the protective effects against H2O2 toxicity via its free radical scavenging activity and ability to elevate the levels of antioxidant enzymes.

[Radiofrequency catheter ablation of arrhythmias in pediatric patients guided by three-dimensional mapping system].

OBJECTIVE: To explore safety, indications and advantages of mapping and ablation of arrhythmia in children guided by Carto and Ensite system. METHODS: Guided by Carto system, radiofrequency catheter ablation (RFCA) was performed on 8 pediatric patients with tachycardia whose mean age was (6.2 + or - 1.7) years, mean weight was (18.0 + or - 2.0) kg. Guided by Ensite system, RFCA was performed on 10 pediatric patients with arrhythmia, 8 of them were ablated guided by Ensite Array system: 6 cases with premature ventricular contractions (PVCs), 2 cases with right atrial tachycardia, their mean age was (11.3 + or - 1.2) years, and mean weight (40.0 + or - 5.0) kg. The other two cases with W-P-W syndrome were ablated guided by Ensite Navx system. RESULT: Guided by Carto system, 8 cases were successfully mapped and ablated: 6 cases had incision atrial tachycardia, 1 case had left atrial tachycardia and 1 case had right atrial tachycardia. In 1 case with incision atrial tachycardia the condition recurred after 3 months, and was ablated again successfully. Guided by Ensite Array system, 6 cases with PVCs (in 2 originating from the right ventricular inflow tract and in 4 originating from the right ventricular outflow tract) and 2 cases with right atrial tachycardia were successfully mapped and ablated, PVCs of the first 6 cases were reduced from (32 333 + or - 4509) 24 h to (0-4)/24 h after ablation. In 1 case with automatic atrial tachycardia, mapping could not be done by Ensite Array system, because P wave could not be identified from T wave. Single bolus of adenosine 20 mg was given within 30 s to let ventricles stop for 2 s (cardio-ventricular pacing standby) until T wave vanished, mapping and ablation were operated again successfully, but another atrial tachycardia occurred 1 day later. Guided by Ensite Navx system, 2 cases with W-P-W syndrome were successfully ablated, operation under X-rays lasted for 8 and 10 min. In none of the 9 patients the disease recurred after follow-up for 6 months. CONCLUSION: Carto system is suitable for mapping and ablation in pediatric patients with continuous tachycardia, especially with incision atrial tachycardia; Ensite Array system fits children older than 10 years with right heart discontinuous arrhythmia; and Ensite NavX system can set up model and display endocardial anatomic structure quickly. Compared with two-dimensional mapping system, the three-dimensional mapping system (Carto and Ensite) can display the origin of arrhythmia and activation sequence clearly, decrease difficulty of operation efficiently and diminish operation time under X-ray.

Radiofrequency catheter ablation of arrhythmias in pediatric patients guided by three-dimensional mapping system / 中华儿科杂志

<p><b>OBJECTIVE</b>To explore safety, indications and advantages of mapping and ablation of arrhythmia in children guided by Carto and Ensite system.</p><p><b>METHODS</b>Guided by Carto system, radiofrequency catheter ablation (RFCA) was performed on 8 pediatric patients with tachycardia whose mean age was (6.2 + or - 1.7) years, mean weight was (18.0 + or - 2.0) kg. Guided by Ensite system, RFCA was performed on 10 pediatric patients with arrhythmia, 8 of them were ablated guided by Ensite Array system: 6 cases with premature ventricular contractions (PVCs), 2 cases with right atrial tachycardia, their mean age was (11.3 + or - 1.2) years, and mean weight (40.0 + or - 5.0) kg. The other two cases with W-P-W syndrome were ablated guided by Ensite Navx system.</p><p><b>RESULT</b>Guided by Carto system, 8 cases were successfully mapped and ablated: 6 cases had incision atrial tachycardia, 1 case had left atrial tachycardia and 1 case had right atrial tachycardia. In 1 case with incision atrial tachycardia the condition recurred after 3 months, and was ablated again successfully. Guided by Ensite Array system, 6 cases with PVCs (in 2 originating from the right ventricular inflow tract and in 4 originating from the right ventricular outflow tract) and 2 cases with right atrial tachycardia were successfully mapped and ablated, PVCs of the first 6 cases were reduced from (32 333 + or - 4509) 24 h to (0-4)/24 h after ablation. In 1 case with automatic atrial tachycardia, mapping could not be done by Ensite Array system, because P wave could not be identified from T wave. Single bolus of adenosine 20 mg was given within 30 s to let ventricles stop for 2 s (cardio-ventricular pacing standby) until T wave vanished, mapping and ablation were operated again successfully, but another atrial tachycardia occurred 1 day later. Guided by Ensite Navx system, 2 cases with W-P-W syndrome were successfully ablated, operation under X-rays lasted for 8 and 10 min. In none of the 9 patients the disease recurred after follow-up for 6 months.</p><p><b>CONCLUSION</b>Carto system is suitable for mapping and ablation in pediatric patients with continuous tachycardia, especially with incision atrial tachycardia; Ensite Array system fits children older than 10 years with right heart discontinuous arrhythmia; and Ensite NavX system can set up model and display endocardial anatomic structure quickly. Compared with two-dimensional mapping system, the three-dimensional mapping system (Carto and Ensite) can display the origin of arrhythmia and activation sequence clearly, decrease difficulty of operation efficiently and diminish operation time under X-ray.</p>

Label-free electrochemical detection of short sequences related to the hepatitis B virus using 4,4'-diaminoazobenzene based on multiwalled carbon nanotube-modified GCE.

A novel label-free electrochemical DNA biosensor based on 4,4'-diaminoazobenzene (4,4'-DAAB) and multiwalled carbon nanotube (MWNT)-modified glassy carbon electrode (GCE) for short DNA sequences related to the hepatitis B virus (HBV) hybridization detection was presented. Differential pulse voltammetry (DPV) was used to investigate hybridization event. The decrease in the peak current of 4,4'-DAAB was observed on hybridization of probe with the target. This electrochemical approach was sequence specific as indicated by the control experiments, in which no peak current change was observed when a noncomplementary DNA sequence was used. Numerous factors affecting the target hybridization were optimized to maximize the sensitivity. Under optimal conditions, this sensor showed a good calibration range between 7.94 x 10(-8) M and 1.58 x 10(-6) M, with HBV DNA sequence detection limit of 1.1 x 10(-8) M.

Investigation of the interaction between ssDNA and 2-aminophenoxazine-3-one and development of an electrochemical DNA biosensor.

An electrochemical method was used to probe the interaction between 2-aminophenoxazine-3-one (AP) and the short DNA sequence related to the hepatitis B virus (HBV), and an electrochemical DNA biosensor was developed. The voltammetric signals of AP have been investigated at bare glassy carbon electrode (bare GCE), hybrid double-stranded DNA-modified GCE (dsDNA/GCE), and single-stranded DNA-modified GCE (ssDNA/GCE) by means of differential pulse voltammetry (DPV), and the peak currents increased with respect to the order of electrodes. The extent of hybridization was evaluated on the basis of the difference between signals of AP with a probe before and after hybridization with the complementary sequence. Control experiments with noncomplementary were performed to test the selectivity of the biosensor. With this approach, a sequence of the HBV could be quantified over the range from 3.53 x 10(-7) to 1.08 x 10(-6) M, with a linear correlation of r = 0.9963 and a detection limit of 1.00 x 10(-7) M.

A nucleic acid biosensor for the detection of a short sequence related to the hepatitis B virus using bis(benzimidazole)cadmium(II) dinitrate as an electrochemical indicator.

A novel hybridization indicator, bis(benzimidazole)cadmium(II) dinitrate (Cd(bzim)(2)(NO(3))(2)), was utilized to develop an electrochemical DNA biosensor for the detection of a short DNA sequence related to the hepatitis B virus (HBV). The sensor relies on the immobilization and hybridization of the 21-mer single-stranded oligonucleotide from the HBV long repeat at the glassy carbon electrode (GCE). The hybridization between the probe and its complementary sequence as the target was studied by enhancement of the peak of the Cd(bzim)(2)(2+) indicator using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Numerous factors affecting the probe immobilization, target hybridization, and indicator binding reactions were optimized to maximize the sensitivity and speed of the assay time. With this approach, a sequence of the HBV could be quantified over the range from 1.49x10(-7)M to 1.06x10(-6)M, with a linear correlation of r=0.9973 and a detection limit of 8.4x10(-8)M. The Cd(bzim)(2)(2+) signal observed from the probe sequence before and after hybridization with a four-base mismatch containing sequence was lower than that observed after hybridization with a complementary sequence, showing good selectivity. These results demonstrate that the Cd(bzim)(2)(2+) indicator provides great promise for the rapid and specific measurement of the target DNA.

Nucleic acid biosensor for detection of hepatitis B virus using 2,9-dimethyl-1,10-phenanthroline copper complex as electrochemical indicator.

In this study, an electrochemical DNA biosensor was developed based on the recognition of target DNA by hybridization detection. The study was carried out using glassy carbon electrode (GCE) modified with lable-free 21-mer single-stranded oligonucleotides related to hepatitis B virus sequence via covalent immobilization and [Cu(dmp)(H(2)O)Cl(2)] (dmp=2,9-dimethyl-1,10-phenanthroline) as an electrochemical indicator, whose sizes are comparable to those of the small groove of native double-duplex DNA. The method, which is simple and low cost, allows the accumulation of copper complex within the DNA layer. Electochemical detection was performed by cyclic voltammetry and differential pulse voltammetry over the potential range where the [Cu(dmp)(H(2)O)Cl(2)] was active. Numerous factors affecting the probe immobilization, target hybridization, and indicator binding reactions were optimized to maximize the sensitivity and speed the assay time. With this approach, a sequence of the hepatitis B virus could be quantified over the ranges from 8.82 x 10(-8) to 8.82 x 10(-7) M with a linear correlation of r=0.9937 and a detection limit of 7.0 x 10(-8) M. The [Cu(dmp)(H(2)O)Cl(2)] signal observed from probe sequence before and after hybridization with four bases mismatch containing sequence is lower than that observed after hybridization with complementary sequence.

Respiratory Parameters of Pressure Support Ventilation and Synchronized Intermittent Mandatory Ventilation during the Weaning Process / 대한마취과학회지

SIMV (synchronized intermittent mandatory ventilation) is a volume assisted mode which a patient inspiratory demand results in a clinician-controlled tidal volume and flow rate. However, PSV (pressure support ventilation) has the ability to augment spontaneous breaths with a variable amount of inspiratory positive pressure with a clinician-selected level of inspiratory airway pressure. To compare the effects of SIMV and PSV on respiratory function, experiments were performed on 12 stable patients during the weaning process and tidal volume, airway pressure, arterial blood gas tensions, blood pressure, and heart rates were measured during SIMV, and after 2 mins after removal of mechanical ventilation support. The same measurement as SIMV (except mandatory respiratory rates) were performed during PSV. The PSV level was reduced in the 5 cm2O step every 10-15 mins. The results of respiratory parameters and hemodynamic data showed that tidal volume, blood pressure, heart rates, and arterial blood gas tensions were similar, but there were significantly lower ventilatory rates, lower peak airway pressure and lower mean airway pressure during PSVmax than SlMV, and PSV resulted in improved patient comfort. It was concluded that PSV could be used to unload the patients ventilatory muscles and provide an appropriate level of mechanical ventilation support similar to SIMV weaning approaches.