Efficient photocatalytic NO removal with inhibited NO2 formation and catalyst loss over sponge-supported and functionalized g-C3N4.

Though photocatalytic purification of NO has been widely studied, how to avoid secondary pollution during gas-solid reaction is still a challenge, especially in inhibiting the formation of toxic intermediates (NO2) and avoiding the blow away of powdery photocatalyst. Herein, we proposed a one-step solvothermal method to prepare melamine sponge (MS) supported and functionalized g-C3N4 (CN), which simultaneously realizes the inhibition of NO2 formation and catalyst loss. Sodium hydroxide, which plays a dual role, has been introduced during the preparation of supported photocatalyst. Specifically, sodium atom, as the modifier of performance, could facilitate the randomly distributed charge of pristine CN to be converged, which accelerates the adsorption/activation of reactants for efficient and deep NO oxidation. Hydroxyl group, as the binder between CN and MS, induces the interaction by forming hydrogen bonds, which contributes to the firm immobilization of powdery photocatalyst. The supported sample exhibits outstanding NO removal rate (58.90%) and extremely low NO2 generation rate (1.41%), and the mass loss rate of photocatalyst before and after reaction is less than 1%. The promotion mechanism of performance also has been elaborated. This work takes environmental risks as a prerequisite to propose a feasible strategy for perfecting the practical application of photocatalytic technology.

Targeted NO Oxidation and Synchronous NO2 Inhibition via Oriented 1O2 Formation Based on Lewis Acid Site Adjustment.

An appealing strategy for ensuring environmental benefits of the photocatalytic NO oxidation reaction is to convert NO into NO3- instead of NO2, yet the selectivity of products remains challenging. Here, such a scenario could be realized by tailoring the exposure of Lewis acid sites on the surface of ZrO2, aiming to precisely regulate the ROS evolution process for the selective oxidation of NO into NO3-. As evidenced by highly combined experimental characterizations and density functional theory (DFT) simulations, Lewis acid sites serving as electron acceptors could induce itinerant electron redistribution, charge-carrier transfer, and further oxidation of •O2-, which promotes the oriented formation of 1O2. As a result, monoclinic ZrO2 with more Lewis acid sites exhibited an outstanding NO conversion efficiency (56.33%) and extremely low NO2 selectivity (5.04%). The ROS-based reaction process and promotion mechanism of photocatalytic performance have been revealed on the basis of ESR analysis, ROS-quenching experiments, and in situ ROS-quenching DRIFTS. This work could provide a critical view toward oriented ROS formation and advance a unique mechanism of selective NO oxidation into NO3-.

Acidic medium synthesis of zeolites - an avenue to control the structure-directing power of organic templates.

This paper deals with the extension of the synthesis field of microporous zeolite-type materials and types of organic structure-directing agents (OSDA) that can be used to promote their crystallization. The highly hydrophilic hexamethylenetetramine (urotropine), with its C/N ratio = 1.5, which is unusual to act as a structure-directing agent in the crystallization of open-framework silica polymorphs, is used to exemplify the novelty of the employed approach. Namely, the protonation of urotropine in an acidic fluorine-containing medium transforms it into a very efficient OSDA that yields dodecasil 3C (MTN-type). This novel synthesis also allows gaining insights into OSDA-framework interactions in the MTN-type structure. The comprehensive 29Si and 19F MAS NMR indicate a small number of point defects of the framework T sites and the multiple bonding of F- ions to Si in a disordered manner. Based on this finding, a unit cell model has been generated using Monte Carlo simulation and validated with Rietveld refinement using experimental powder X-ray diffraction data. In the model, protonated urotropine cations are located in the center of the big hexakaidecahedral [51264] cages at full occupancy with random orientations. The charge balance is provided by the disordered F- ions.

Expression and clinical significance of serum amyloid A and interleukin-6 in patients with acute exacerbation of chronic obstructive pulmonary disease.

Expression and clinical significance of serum amyloid A (SAA) and interleukin-6 (IL-6) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) were investigated. Fifty-one patients with AECOPD (acute group, AG) and 51 patients with stable chronic obstructive pulmonary disease (stable group, SG) admitted to Qingdao Eighth People's Hospital were selected. The expression levels of SAA and IL-6 in peripheral blood of patients in the two groups were detected and compared before and after treatment. Pearson analysis was used in the correlation between SAA and IL-6 and Receiver operating characteristic (ROC) curve was employd to analyze the predictive value of SAA and IL-6 for AECOPD progression. Logistic regression analysis was used to analyze the risk factors of AECOPD patients. The expression levels of SAA and IL-6 of patients in AG were significantly higher than those in SG (P<0.05). Pearson analysis showed that SAA was positively correlated with IL-6 expression (P<0.05). ROC curve analysis showed that AUC predicted by SAA and IL-6 for AECOPD progress was 0.789 and 0.762 (P<0.05). Logistic regression analysis showed that SAA and IL-6 were prediction indexes of AECOPD progression. The levels of SAA and IL-6 were significantly increased during AECOPD and effectively predicted the progress of AECOPD and is a risk factor affecting AECOPD patients.

A bi-polyoxometallate-based host-guest metal-organic framework.

Anionic POMs prefer to bond with positive metal cations instead of neutral or negative organic ligands. Therefore, it is challenging to synthesize POM-based MOFs, let alone bi-POM-based host-guest MOFs. In this work, an unprecedented bi-POM-based host-guest MOF, Na[Ni(enMe)2]4[Ni(enMe)2(H2O)2]2{[Ni6(µ3-OH)3(enMe)3 (SIP)1.5(B-α-PW9O34)]2[H3PNiW11O40]}·5enMe·33H2O (1), with Ni6-capped [PW9O34] as the node of the host framework and Keggin-type [PNiW11O40] units as the guest was synthesized. 1 showed excellent chemical stability towards aqueous solutions of pH 2-12 at both ambient and boiling temperature, providing opportunities for its application in fresh water harvesting from air.

[The frequency, phenotypes and functions of CD4+ CD25+ regulatory T cells in hepatocellular carcinoma patients].

OBJECTIVES: (1) To evaluate the prevalence, phenotypes and suppressive function of CD4+CD25+ regulatory T cells (Tregs) among the in peripheral blood mononuclear cells (PBMCs) and tumor-infiltration lymphocytes (TILs) from hepatocellular carcinoma (HCC) patients and patients with chronic hepatitis B. (2) To investigate the correlation between the frequency of CD4+CD25+ Tregs and clinical characteristics of HCC patients. METHODS: PBMCs and TILs in 18 HCC patients, 10 chronic hepatitis B (CHB) patients and 15 healthy donors were evaluated for the phenotypes of CD4+CD25+ Tregs and the proportion of CD4+CD25+ Tregs as a percentage of the total CD4+ cells, by flow cytometric analysis with three or four color staining. The relationship between the frequency of CD4+CD25+ Tregs and tumor TNM stages was analyzed. The CD4+CD25+ Tregs and CD4+CD25- T cells were isolated from PBMC of HCC patients and donors. The suppressive function of CD4+CD25+ Tregs was analyzed. RESULTS: The percentages of CD4+CD25+ Tregs of the HCC patients (6.38% +/- 6.30%) and CHB patients (4.29% +/- 1.82%) were significantly higher than those of the healthy donors (1.58% +/- 0.55%, P less than 0.01). Among the TILs, the percentage of CD4+CD25+ Tregs was higher (t = 4.39, P < 0.01). There were significant differences in the prevalence of CD4+CD25+ Tregs in early and advanced stage HCCs (stage II vs. III, P less than 0.05; stage II vs. IV P < 0.01). The proliferative capacity of CD4+CD25- T cells was inhibited by the presence of CD4+CD25+ T cells in a dose-dependent manner where the level of suppression was correlated to the ratio of the two-cell populations. CONCLUSION: These results suggest that the increase in frequency of CD4+CD25+ Tregs might play a role in the suppression of the immune response against HCC, which may contribute to the HCC cells that escaped from immunological surveillance.

Transfusion of multi-factors activated immune cells as a novel treatment for patients with chronic hepatitis B.

BACKGROUND AND OBJECTIVES: Host-virus interactions play a central role in determining the prognosis of hepatitis B virus infection. Multi-factors activated immune cells (MAICs) are autologous peripheral blood mononuclear cells activated with anti-CD3 monoclonal antibody, interleukin-2 and interferon-gamma. The present pilot clinical trial was designed to determine whether adoptively transferred MAICs inhibit the replication of hepatitis B virus and is safe for patients. STUDY DESIGN: Fourteen patients with chronic hepatitis B were enrolled in the study. A total of (1.5-4.0)x10(9) peripheral blood mononuclear cells were isolated from each patient and activated by anti-CD3 monoclonal antibody, interleukin-2 and interferon-gamma in vitro for 10 days to produce MAICs. Cell phenotypes and levels of cytokine secretion were determined during cell culture. Patients were followed up for 1 year after the transfusion of MAICs. RESULTS: After 10 days of culture, peripheral blood mononuclear cells were expanded to a mean fold of 4.68+/-1.78 and activated effectively, as demonstrated by CD25 expression and cytokine secretion. Cell activation peaked on day 4. All patients accepted the MAICs transfusion with some slight adverse events, and fulminant hepatitis and bilirubinemia were not observed. Significant HBV inhibition was observed in 8 out of 14 patients, in which 5 patients achieved complete response (defined as that serum HBV DNA levels below the detection limit, occurrence of HBeAg seroconversion and normalization of ALT were observed together after MAICs transfusion and kept for at least 6 months) and 3 patients achieved partial response (defined as that serum HBV DNA levels below the detection limit, occurrence of HBeAg disappearance and normalization of ALT were observed together in 6 months after MAICs transfusion, but kept for less than 6 months). CONCLUSION: These findings strongly suggest that MAICs transfusion, which effectively inhibits the replication of hepatitis B virus, is safe for patients.

Dendritic cells from chronic hepatitis B patients can induce HBV antigen-specific T cell responses.

AIM: To determine whether dendritic cells (DCs) from chronic hepatitis B patients could induce HBV antigen-specific T cell responses or not. METHODS: DCs were generated from peripheral blood mononuclear cells of patients with chronic hepatitis B (CHB) infection and healthy donors. We compared the phenotypes of these DCs and their ability to secrete cytokines and to participate in mixed lymphocyte reactions. In addition, autologous lymphocytes were cultured with DCs loaded with HBV core region peptide HBcAg8-27, an epitope recognized by cytotoxic T lymphocytes (CTL), and bearing human leucocyte antigen (HLA)-A2 for 10 d. Cytokine secretion and lytic activity against peptide-pulsed target cells were assessed. RESULTS: DCs with typical morphology were generated successfully by culturing peripheral blood mononuclear cells (PBMCs) from CHB patients with AIM-V containing GM-CSF and IL-4. Compared with DCs from normal donors, the level of CD80 expressed in DCs from CHB patients was lower, and DCs from patients had lower capacity of stimulate T cell proliferation. When PBMCs isolated from patients with chronic or acute hepatitis B infection and from normal donors were cocultured with HBcAg18-27 peptide, the antigen-specific memory response of PBMCs from acute hepatitis B patients was stronger than that of PBMCs from chronic hepatitis B patients or normal donors. PBMCs cocultured with DCs treated with HBcAg18-27 CTL epitope peptide induced an antigen-specific T cell reaction, in which the level of secreted cytokines and lytic activity were higher than those produced by memory T cells. CONCLUSION: DCs from patients with CHB can induce HBV antigen-specific T cell reactions, including secretion of cytokines essential for HBV clearance and for killing cells infected with HBV.

[Impaired non-viral specific immune function of dendritic cell does not interfere with clearance and cytotoxic T lymphocyte response to HBV or HCV].

OBJECTIVE: To investigate the correlation between impaired non-viral specific immune function of dendritic cell (DC) and viral clearance and cytotoxic T lymphocyte (CTL) response to HBV or HCV in patients with HBV and HCV coinfection. METHODS: Twenty-five patients with HBV and HCV coinfection were investigated in this study. In 1994 and 2002, biochemical and virological markers and quantitative serum HBV DNA and HCV RNA levels were detected in these patients. According to the virus clearance status, these patients were divided into 4 groups: 14 patients with both HBV and HCV clearance (Group A), 6 patients with HCV clearance only (Group B), 3 patients with HBV clearance only (Group C), and 2 patients with persistent infection of HBV and HCV (Group D). Phenotypes and immune functions of monocyte-derived DCs were compared between these groups. 51Cr release assay were used to measure CTL response to epitopes derived from HBV, HCV or influenza virus (as positive control) in HLA-A2+ patients. RESULTS: Impaired non-viral specific immune functions of DCs were observed in group B, C and D compared with group A and normal donors (Group N). These impaired functions included CD86 decreasing expression and lower capacity to stimulating allogenic T cells and uptaking antigen. The specific CTL response to HBV- and HCV-derived peptides could be induced in group A (12/12). The specific CTL response to HBV-derived peptides or to HCV-derived peptides could be induced in group C (3/3) or B (5/5), respectively. But the specific CTL response to both of two HBV-derived peptides or two HCV-derived peptides could not be induced in group C (0/3) or B (0/5), respectively. And no CTL response to HBV or HCV-derived peptides could be induced in groups D (0/1) and N (0/4). CONCLUSION: 1. The results suggest that specific CTL response to HBV or HCV play a vital role in the viral clearance. 2. The DCs with impaired non-viral specific immune functions exist in chronic patients with HBV and/or HCV infection, but do not interfere with clearance and CTL response to HBV or HCV. It is reasonable to speculate that impaired functions of DCs result from viral infection.

[Dendritic cells originated from the peripheral blood in chronic hepatitis B patients can induce specific T cell immune response].

OBJECTIVE: To study whether dendritic cells (DCs) derived from the peripheral blood in chronic hepatitis B patients can induce specific T cell immune response. METHODS: (1)The subjects were divided into 3 groups: chronic hepatitis B group (CHB), acute hepatitis B group (AHB), and normal donor group (ND). The peripheral blood mononuclear cells (PBMCs) isolated from those subjects were stimulated with HBcAg 18 to 27 CTL epitope peptide, and intracellular cytokine staining (ICCS) was used for detecting IFN-gamma, IL-2 and TNF-alpha produced by CD8+ T cell. (2) DCs generated from PBMCs were pulsed with HBcAg 18 to 27 CTL epitope peptide, then were cocultured with autologous lymphocytes for 10 days to induce antigen-specific T cell, which was assessed by ICCS and cytotoxic assay. RESULTS: (1) The memory effect of the PBMCs from AHB group to HBcAg 18 to 27 CTL epitope peptide was stronger than that from CHB or ND group (t=2.508-3.305, P<0.05). (2)After lymphocytes were cocultured with DC treated with HBcAg 18 to 27 CTL epitope peptide, antigen-specific T cell effect was induced. And the killing rates were (57.0+/-23.0)%, (49.5+/-20.2)%, (21.8+/-12.9)% at the effector/target of 30:1, 10:1, 3:1, which were higher than that in control group. CONCLUSIONS: The memory T cells against HBV antigen lacks in CHB patients. DCs from CHB patients pulsed with HBcAg 18 to 27 epitope peptide can induce HBV antigen-specific T cell, which can kill specific target cells and produce cytokines involved in virus clearance.

[Autologous adoptive immunotherapy without destruction of infected cells during the treatment of chronic hepatitis B].

OBJECTIVES: To investigate the profile of liver histological damage after autologous adoptive immunotherapy with cytokine-induced killer cells (CIK cells) in patients with chronic hepatitis B (CHB). METHODS: 16 CHB patients were randomly enrolled and received autologous adoptive immunotherapy, then followed up 52 weeks. Liver samples were taken from the patients to evaluate the degree of inflammation and fibrosis. The markers of hepatitis B virus and liver function were also detected. RESULTS: 4 patients had two liver-biopsied samples before therapy and after 52 weeks follow-up. One patient's histological assessment revealed a significant improvement in intralobular necroinflammation (G2 --> G1) and fibrosis (S2 --> S1). The others failed to show obvious changes in liver histology. After 10 days culture in vitro, phenotypic characterization of CIK cells changed significantly by flow cytometry. The percentage of CD4+ cells decreased gradually, while the percentage of CD8+ cells increased from 20% to 60% - 80%. After 52 weeks follow-up, HBV DNA was negative (HBV DNA<4pg/ml in serum) in 6 out of 14 patients. The rates of both HBeAg/anti-HBe seroconversion and alanine aminotransferase normalization were 42.86%(6/14). There was no HBsAg/anti-HBs seroconversion. There was few severe treatment-related adverse events. CONCLUSION: Autologous adoptive immunotherapy doesn't induce the damage of liver histology in chronic hepatitis B patients, which inhibits hepatitis B virus replication by a certain noncytotoxic mechanism.