Research on the shielding effect of the electrode frames in the electrostatic precipitator.

The electrostatic precipitator (ESP) plays an important role in the dust removal from the flue gas. Currently, the shielding effect of electrode frames seriously affects the electric field distribution and dust removal efficiency of ESPs. In order to explore the shielding effect and propose an improved measurement, an experimental setup with RS barbed electrodes and a 480 C type dust collector electrode plate was built to evaluate the corona discharge characteristics. The current density distribution on the surface of the collecting plate was tested on an ESP experimental setup. The effect of electrode frames on the current density distribution was also systematically investigated. The test results show that the current density distribution on the position that directly opposites the needle of RS corona discharge is much higher, on the contrary, the current density on the position that directly opposites the frames is almost zero. It indicates that the frames have a shielding effect on the corona discharge. Therefore, the dust collection efficiency is low in actual ESPs due to the dust escape route caused by the shielding effect. To solve the problem, a new ESP with a split-level frame arrangement was proposed.Implications: The conventional electrostatic precipitators are often affected by the electrostatic shielding effect, which leads to uneven charging. The particulate removal efficiency decreases and escape channels are very easy to form. In this study, effective measures were proposed to solve the electrostatic shielding of dust collector frames by studying their electrostatic shielding mechanism. The study provides theoretical support for the improvement of electrostatic precipitators, while improving the dust removal efficiency.

Peroxiredoxin 6 translocates to the plasma membrane of human sperm under oxidative stress during cryopreservation.

Peroxiredoxin 6 (PRDX6) is one antioxidant enzyme which could control the levels of reactive oxygen species and to avoid oxidative damage of sperm. In this study, we aimed to investigate the position change of PRDX6 in human sperm under oxidative stress during cryopreservation. Semen samples were obtained from 98 healthy donors and 27 asthenozoospermic donors. The plasma membrane protein and cytoplasmic protein of sperm samples were extracted and analyzed after cryopreservation. Western blot and immunofluorescence were used to measure the expressions of PRDX6. Liquid chromatography mass spectrometric (LC-MS/MS) analysis was performed to confirm the component of sperm membrane complex. Western blot showed that the detection rate of PRDX6 in plasma membranes with low sperm motility (≤20%) was significantly higher than that with high sperm motility (≥40%). Western blot and Immunofluorescence revealed that cryopreservation and thawing induced the position change of the PRDX6 from cytoplasm to sperm membrane. LC-MS/MS analysis showed that PRDX6, ADP/ATP translocase 4 (ANT4) and glyceraldehyde-3-phosphte dehydrogenase (GAPDHS) were present in the components of membrane complex after cryopreservation. The present study indicated that the presence of PRDX6 in sperm plasma membrane was related to sperm motility. GAPDHS and ANT4 may be involved the position change of the PRDX6 from cytoplasm to sperm membrane under oxidative stress during cryopreservation.

Insights into the effect of the shape of collecting plates on particle precipitation processes in an electrostatic precipitator.

Collecting plate is the core component of the electrostatic precipitator. In order to explore the influences of the plates shape and electrode configuration on the particle precipitation process, numerical models of an ESP with seven different types of collecting plates were established and calculated. The simulation results showed that the shape of the collecting plate did have a great impact on the electric field, airflow particles movement. From the perspective of electric field characteristics, the space current density and electrostatic shielding effect in multielectrode ESPs varied with the shape of the plates under the same supply voltage. When using C-type plate, the shielding effect was minimal and the current density distribution of the plate was more uniform. When it comes to airflow distribution, small vortex structures were easily generated near the plates when the CW type, the rod-curtain and Z-type plates were used, leading to particle re-entrainments. In terms of collection efficiency, the C-type plate enjoyed the highest efficiency, while the ZT-type and corrugated plate were less efficient. Implications: The main source of air pollution is the flue gas released by fuel combustion. electrostatic precipitator plays an important role in pollutant discharge control and environmental protection. As the core component of the electrostatic precipitator, the form of the collecting plate exerts a serious impact on its dust removal performance. The study focuses on the analysis of the collecting plate shape on the electric field characteristics of electrostatic precipitators, flow distribution characteristics and the influence of the collecting efficiency. It is expected that through the research, some guidance will be provided with the electrode configuration selection and optimization of ESP.

Proteomic analysis at the subcellular level for host targets against influenza A virus (H1N1).

Influenza viruses (IVs) trigger a series of intracellular signaling events and induce complex cellular responses from the infected host cell. Accumulating evidence suggests that host cell proteins play an essential role in viral propagation and represent novel antiviral therapeutic targets. Subcellular proteomic technology provides a method for understanding regional differences at the protein level. The present study, which utilized subcellular proteomic technology, aimed to identify host cell proteins involved in influenza virus (HIN1) infection. Two-dimensional gel electrophoresis (2-DE) combined with mass spectrum (MS) was performed on protein extracts from the nuclei, cytoplasm, and mitochondria of infected and control human lung epithelial cells (A549). In total, 112 differentially expressed protein molecules were identified; 80 protein spots were successfully validated using MS. The differential expression of ISG15, MIF, PDCD5, and UCHL1 was confirmed by western blot. Furthermore, antisense oligodeoxyribonucleotide (ODN) targeting ISG15, MIF, PDCD5, and UCHL1 significantly mitigated HIN1 propagation, cytopathic effects, vRNA by RT-qPCR, and rescued cell viability in A549 cells. Taken together, the differentially expressed proteins identified in this study might provide novel targets for anti-influenza drug development.

Cellular microRNA let-7c inhibits M1 protein expression of the H1N1 influenza A virus in infected human lung epithelial cells.

The influenza virus (IV) triggers a series of signalling events inside host cells and induces complex cellular responses. Studies have suggested that host factors play an essential role in IV replication. MicroRNAs (miRNAs) represent a class of small non-coding RNAs that target mRNAs, triggering either translation repression or RNA degradation. Emerging research suggests that host-derived cellular miRNAs are involved in mediating the host-IV interaction. Using miRNA microarrays, we identified several miRNAs aberrantly expressed in IV-infected human lung epithelial cells (A549). Specifically, miR-let-7c was highly up-regulated in IV-infected A549 cells. PITA and miRanda database screening indicated that the let-7c seed sequence is a perfect complementary sequence match to the 3' untranslated region (UTR) of viral gene M1 (+) cRNA, but not to PB2 and PA. As detected by a luciferase reporter system, let-7c directly targeted the 3'-UTR of M1 (+) cRNA, but not PB2 and PA. To experimentally identify the function of cellular let-7c, precursor let-7c was transfected into A549 cells. Let-7c down-regulated IV M1 expression at both the (+) cRNA and protein levels. Furthermore, transfection with a let-7c inhibitor enhanced the expression of M1. Therefore, let-7c may reduce IV replication by degrading M1 (+) cRNA. This is the first report indicating that cellular miRNA regulates IV replication through the degradation of viral gene (+) cRNA by matching the 3'-UTR of the viral cRNA. These findings suggest that let-7c plays a role in protecting host cells from the virus in addition to its known cellular functions.

Ginsenoside Rg1 protects rat cardiomyocyte from hypoxia/reoxygenation oxidative injury via antioxidant and intracellular calcium homeostasis.

Ginsenoside Rg1 is a major active ingredient of Panax notoginseng radix which has demonstrated a number of pharmacological actions including a cardioprotective effect in vivo. This study investigated the protective effect and mechanism of ginsenoside Rg1 in cardiomyocytes hypoxia/reoxygenation (H/R) model. Pretreatment with ginsenoside Rg1 (60-120 microM) reduced lactate dehydrogenase release and increased cell viability in a dose-dependent manner. Fluorescence analysis demonstrated ginsenoside Rg1 reduced intracellular ROS and suppressed the intracellular [Ca(2+)] level. Cell lysate detected an increase of T-SOD, CAT, and GSH levels. The myocardial protection of ginsenoside Rg1 during H/R is partially due to its antioxidative effect and intracellular calcium homeostasis.

Proteomic analysis of ionizing radiation-induced proteins at the subcellular level.

Irradiation induces a series of liver diseases. However the molecular mechanisms involving in the process of liver diseases induced by irradiation are still unclear. Subcellular proteomics provides a method to understand regional differences in protein expression levels. With accumulating evidence in the literature that new proteins are implicated in radiation response, in the present study, C57BL/6 mice were treated with irradiation, liver cell homogenates were subfractionated by differential ultracentrifugation into nuclei, mitochondria and cytosol, which were subjected to 2-DE to generate the proteomic maps of these fractions. The differentially expressed proteins in the nuclei, mitochondria and cytosol compartment of liver at 24 and 48 h after exposure to 20 Gy irradiation compared to control were identified by MALDI-TOF MS respectively. Total 37 proteins at 24 h and 29 proteins at 48 h were matched with known proteins after database searching in nuclei, mitochondria and cytosol, respectively, among which nine proteins exhibited changes at both time points. Most of these proteins are involved in antioxidant response, energy metabolism, molecular chaperones and inflammatory response. More antioxidant-associated proteins were induced at 48 h than 24 h. Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting further validated 2-DE results of two of these proteins. It is feasible that the differential proteins identified in this study have a biological significance and may provided clues for understanding the mechanism of injury in liver induced by irradiation.

Salvianolic acid B, an antioxidant from Salvia miltiorrhiza, prevents 6-hydroxydopamine induced apoptosis in SH-SY5Y cells.

Oxidative stress caused by dopamine may play an important role in the pathogenesis of Parkinson's disease. Salvianolic acid B is an antioxidant derived from the Chinese herb, Salvia miltiorrhiza. In this study, we investigated the neuroprotective effect of salvianolic acid B against 6-hydroxydopamine-induced cell death in human neuroblastoma SH-SY5Y cells. Pretreatment of SH-SY5Y cells with salvianolic acid B significantly reduced 6-hydroxydopamine-induced generation of reactive oxygen species, and prevented 6-hydroxydopamine-induced increases in intracellular calcium. Our data demonstrated that 6-hydroxydopamine-induced apoptosis was reversed by salvianolic acid B treatment. Salvianolic acid B reduced the 6-hydroxydopamine-induced increase of caspase-3 activity, and reduced cytochrome C translocation into the cytosol from mitochondria. The 6-hydroxydopamine-induced decrease in the Bcl-x/Bax ratio was prevented by salvianolic acid B. Additionally, salvianolic acid B decreased the activation of extracellular signal-regulated kinase and induced the activation of 6-hydroxydopamine-suppressed protein kinase C. These results indicate that the protective function of salvianolic acid B is dependent upon its antioxidative potential. Our results strongly suggest that salvianolic acid B may be effective in treating neurodegenerative diseases associated with oxidative stress.