ABSTRACT
Recently, graphitic carbon nitride (g-C3 N4 ) has attracted increasing interest due to its visible light absorption, suitable energy band structure, and excellent stability. However, low specific surface area, finite visible light response range (<460 nm), and rapid photogenerated electron-hole (e- -h+ ) pairs recombination of the pristine g-C3 N4 limit its practical applications. The small size of quantum dots (QDs) endows the properties of abundant active sites, wide absorption spectrum, and adjustable bandgap, but inevitable aggregation. Studies have confirmed that the integration of g-C3 N4 and QDs not only overcomes these limitations of individual component, but also successfully inherits each advantage. Encouraged by these advantages, the synthetic strategies and the fundamental of QDs/g-C3 N4 composites are briefly elaborated in this review. Particularly, the synergistic effects of QDs/g-C3 N4 composites are analyzed comprehensively, including the enhancement of the photocatalytic performance and the avoidance of aggregation. Then, the photocatalytic applications of QDs/g-C3 N4 composites in the fields of environment and energy are described and further combined with DFT calculation to further reveal the reaction mechanisms. Moreover, the stability and reusability of QDs/g-C3 N4 composites are analyzed. Finally, the future development of these composites and the solution of existing problems are prospected.
ABSTRACT
BACKGROUND: Human papillomavirus (HPV) infections were the main cause of anogenital cancers and warts. HPV 6/11/16/18 vaccines provide protection against the high-risk types of HPV responsible for 70% of cervical cancers and 90% of genital warts. This randomized, blinded, non-inferiority phase III trial was to determine whether immunogenicity and tolerability would be non-inferior among women after receiving two novel 4- and 9-valent HPV vaccines (4vHPV, HPV 6/11/16/18; 9vHPV, HPV 6/11/16/18/31/33/45/52/58) compared with those receiving Gardasil 4 (4-valent). METHODS: 1680 females between 20 and 45 years were randomized in a 2:1:1 ratio to 20-26, 27-35, or 36-45 y groups. Subjects then equally assigned to receive 4vHPV, 9vHPV or Gardasil 4 (control) vaccine at months 0, 2, and 6. End points included non-inferiority of HPV-6/11/16/18 antibodies for 4vHPV versus control, and 9vHPV versus control and safety. The immunogenicity non-inferiority was pre-defined as the lower bound of 95% confidence interval (CI) of seroconversion rate (SCR) difference > -10% and the lower bound of 95% CI of geometric mean antibody titer (GMT) ratio > 0.5. RESULTS: Among the three vaccine groups, more than 99% of the participants seroconverted to all 4 HPV types. The pre-specified statistical non-inferiority criterion for the immunogenicity hypothesis was met: all the lower bounds of 95% CIs on SCR differences exceeded -10% for each vaccine HPV type and the corresponding lower bounds of 95% CIs for GMT ratios > 0.5. Across vaccination groups, the most common vaccination reaction were injection-site adverse events (AEs), including pain, swelling, and redness. General and serious AEs were similar in the three groups. There were no deaths. CONCLUSIONS: This study demonstrated that the novel 4- and 9-valent HPV vaccination was highly immunogenic and generally well tolerated, both of which were non-inferior to Gardasil 4 in immunogenicity and safety.
Subject(s)
Papillomavirus Infections , Papillomavirus Vaccines , Uterine Cervical Neoplasms , Female , Humans , Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18/adverse effects , Papillomavirus Infections/prevention & control , Gammapapillomavirus , Antibodies, Viral , Uterine Cervical Neoplasms/prevention & control , Papillomaviridae , China , Immunogenicity, VaccineABSTRACT
Composting, as a conventional solid waste treatment method, plays an essential role in carbon and nitrogen conservation, thereby reducing the loss of nutrients and energy. However, some carbon- and nitrogen-containing gases are inevitably released during the process of composting due to the different operating conditions, resulting in carbon and nitrogen losses. To overcome this obstacle, many researchers have been trying to optimize the adjustment parameters and add some amendments (i.e., pHysical amendments, chemical amendments and microbial amendments) to reduce the losses and enhance carbon and nitrogen conservation. However, investigation regarding mechanisms for the conservation of carbon and nitrogen are limited. Therefore, this review summarizes the studies on physical amendments, chemical amendments and microbial amendments and proposes underlying mechanisms for the enhancement of carbon and nitrogen conservation: adsorption or conversion, and also evaluates their contribution to the mitigation of the greenhouse effect, providing a theoretical basis for subsequent composting-related researchers to better improve carbon and nitrogen conservation measures. This paper also suggests that: assessing the contribution of composting as a process to global greenhouse gas mitigation requires a complete life cycle evaluation of composting. The current lack of compost clinker impact on carbon and nitrogen sequestration capacity of the application site needs to be explored by more research workers.
Subject(s)
Composting , Carbon , Composting/methods , Gases , Greenhouse Effect , Humans , Manure , Nitrogen/analysis , SoilABSTRACT
Sulfate radical (SO4â¢-) based advanced oxidation processes (SR-AOPs) is a very important chemical oxidation technology for the degradation of recalcitrant organic pollutants in water and has been well developed. Recently, transition metals or their oxides-modified biochar has been widely used as the catalyst to catalyze peroxymonosulfate (PMS) and peroxydisulfate (PS) in SR-AOPs due to their outstanding properties (e.g., large surface area, high stability, abound catalytic sites, and diversity of material design, etc.). These composite materials not only combine the respective beneficial characteristics of biochar and transition metals (or their oxides) but also often present synergistic effects between the components. In this review, we present the synthesis of different types of transition metal (or metal oxides)/biochar-based catalysts and their application in SR-AOPs. The catalytic mechanism, including the generation process of free radicals and other reaction pathways on the surface of the catalyst were also carefully discussed. Particular attention has been paid to the synergistic effects between the components that result in enhanced catalytic performance. At the end of this review, the future development prospects of this technology are proposed.
Subject(s)
Charcoal , Water Pollutants, Chemical , Oxidation-Reduction , Oxides , Sulfates , Water Pollutants, Chemical/chemistryABSTRACT
The heterogeneous Fenton-like reaction is an advanced oxidation process, which is widely recognized for its efficient removal of recalcitrant organic contaminants. In recent years, the construction of efficient and reusable heterogeneous Fenton-like catalysts has been extensively investigated. Recently, the use of bimetallic oxides and their complexes as catalysts for Fenton-like reaction has attracted intense attention due to their high catalytic performance and excellent stability over a wide pH range. In this article, the fundamental mechanisms of Fenton-like reactions were briefly introduced. The important reports on bimetallic oxides and their complexes are classified in detail, which are mainly divided into Fe-based and Fe-free bimetallic catalysts. We then focused in depth on the performance of their respective applications in Fenton-like reactions. Special consideration has been given to the respective contributions and synergistic mechanisms of the two metals in catalysts. Overall, it is concluded that synergistic effect of the two metals in the bimetallic catalyst can boost the utilization of hydrogen peroxide, provide adequate accessible active sites, which are all beneficial to improve catalytic performance. Finally, the current challenges in this field were proposed. Our review is expected to provide help for the application of bimetallic oxides and their complexes.
Subject(s)
Iron , Oxides , Catalysis , Hydrogen Peroxide , Oxidation-ReductionABSTRACT
The effect of microplastics on soil ecosystem is a hot topic in recent years. It is increasingly recognized that soil is also an important sink for microplastics in addition to the aquatic environment. This review aims to discuss the direct and indirect effects of microplastics on the soil-plant system, focusing on the effects of microplastics on soil aggregates and soil nutrient cycling as well as the combined effects of microplastics and other pollutants on soil-plant systems. Microplastics have been shown to affect the rooting ability of plants by altering soil bulk density and water-holding capacity, as well as reducing photosynthetic rate by directly interfering with the balance of plant chlorophyll a/chlorophyll b ratios. In addition, microplastics affect the stability of aggregates by interfering with abiotic factors (e.g., sesquioxide and exchangeable cations) or biotic factors (e.g., soil organic matter and organism activities in the soil). Moreover, microplastics may affect soil nutrient cycling by altering the dominant bacteria phyla in the soil or genes and enzymes associated with the carbon, nitrogen, and phosphorus cycle. When microplastics and other pollutants have combined effects on plants, microplastics attached onto the root surface physically hamper the contact of the pollutants with the roots but are more likely to exacerbate the damage of pollutants to plants. Different types, sizes and concentrations of microplastics have different effects on the soil-plant system. Microplastics with similar shape and size to soil particles have less significant effects, while microfibers, small-sized microplastics and biodegradable plastic particles have more significant effects. Finally, this review also provides an outlook for future research.
Subject(s)
Microplastics , Soil , Chlorophyll A , Ecosystem , PlasticsABSTRACT
Poly- and perfluoroalkyl substances (PFASs) are a group of emerging organic contaminants which are persistent to normal physicochemical treatments. The widespread use of PFASs has caused significant environmental issues. The bioaccumulation and distribution of PFASs within plant compartments have revealed great potentials for phytoremediation. In this review, the roles of aquatic plants in the process of PFASs remediation were highlighted. Moreover, there were different underlying mechanisms of PFASs uptake between terrestrial and aquatic plants. On the other hand, a wide range of influencing factors for bioaccumulation and translocation of PFASs within plant compartments are also presented and discussed. In response to exposure of PFASs, corresponding phytotoxic effects has affected the growth and metabolism of plants, which could provide beneficial guides of the phytotoxic tolerance for plant species selection in applications of phytoremediation. Finally, the discussion about whether phytoremediation is a viable option for PFASs removal and further research priorities are suggested.
Subject(s)
Fluorocarbons , Water Pollutants, Chemical , Biodegradation, Environmental , Fluorocarbons/analysis , Fluorocarbons/toxicity , Plants , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicityABSTRACT
Metal organic frameworks (MOFs) have great potential for photocatalysis, but only possess moderate activity due to their slow charge transfer and low solar energy conversion. Herein, heterostructures photocatalysts constructed by boron nitride quantum dots (BNQDs) and MIL-100(Fe) (MNB) were successfully fabricated for overcoming these shortcomings. It was indicated that the composites possessed large surface area, mesoporous structure, and enhanced visible light absorption. The MNB photocatalysts exhibited excellent photocatalytic activity for tetracycline hydrochloride (TC-HCl) degradation under visible light irradiation. Compared with MIL-100(Fe), the photodegradation rate of TC-HCl by MNB-1 was 0.02383 min-1, which was 5.3 times higher than that of pure MIL-100(Fe). The close contact of MIL-100(Fe) with BNQDs and the synergistic effect between them were the main reasons for the improved photodegradation performance. This study reveals that a rational combination of MIL-100(Fe) and BNQDs can improve photocatalytic activity to enhance molecular oxygen activation. Therefore, it is reasonable to believe that quantum dots/MOFs photocatalysts have great potential in environmental remediation.
Subject(s)
Anti-Bacterial Agents , Quantum Dots , Boron Compounds , CatalysisABSTRACT
As environmental problems become more and more severe, sulfate radical (SO4-) based advanced oxidation processes (SR-AOPs) are widely recognized for their high removal efficiency of recalcitrant organic pollutants in water. Metal-organic frameworks (MOFs) have attracted wide attention in SR-AOPs due to their outstanding properties (e.g. large surface area, ultra-high porosity, and diversity of material design, etc). Herein, we present an overview of the development and challenges in the synthesis of different types of MOFs, combination of MOFs with other materials (metal centers, conductors, cellulose, etc.) and the construction of catalysts with special structures (core-shell structures and hollow structures) as well as their applications in SR-AOPs for the degradation of organic pollutants. Several review papers have already mentioned the application of a branch of MOFs or simple composites of MOFs in SR-AOP, whereas the latest progresses on the application of MOFs-based materials to SR-AOPs was described rarely. Besides, the degradation mechanism of MOFs as catalysts has not been systematically discussed. To this end, the mechanisms of MOFs and MOF-based materials as catalysts to activate PMS/PS in different systems are analyzed, including radicals and non-radicals pathways. Meanwhile, considering that the research in this field is still in its infancy, a lot of improvements are still needed to effectively promote and implement this technology.
Subject(s)
Metal-Organic Frameworks , Water Purification , Catalysis , Oxidation-Reduction , WaterABSTRACT
Human papillomaviruses (HPV), particularly HPV16, are associated with most cervical cancers. Currently, although prophylactic vaccines have been developed, there is still an urgent need to develop therapeutic HPV vaccines. In this study, a novel fusion protein, HPV 16 E7-HBcAg-Hsp65 (VR111), with the goal of increasing anti-HPV16 cellular immunity was developed. VR111 was analyzed using SDS-PAGE, western-blotting, capillary isoelectric focusing (cIEF), analytical ultracentrifugation (AUC) and dynamic light scattering (DLS). Gamma interferon (IFN-γ) secretion assay was performed by enzyme-linked immunospot (ELISPOT) and ELISA to test their ability to induce cellular immune response. Significant correlation between ELISPOT and ELISA was observed (r=0.8680, p<0.0001). It was shown that VR111 could induce a significant increase in E7-specific CD8(+) T cell responses. Humoral immune response was also observed. The antibody titer levels were measured by ELISA. These results indicated that VR111 was a promising therapeutic vaccine for treatment of cervical cancer with possible therapeutic potential in clinical settings.
Subject(s)
Papillomavirus Infections/therapy , Papillomavirus Vaccines/administration & dosage , Papillomavirus Vaccines/immunology , Animals , Antibodies, Viral/blood , CD8-Positive T-Lymphocytes/immunology , Enzyme-Linked Immunosorbent Assay , Enzyme-Linked Immunospot Assay , Female , Heat-Shock Proteins/genetics , Hepatitis B Core Antigens/genetics , Interferon-gamma/metabolism , Mice , Mice, Inbred C57BL , Papillomavirus E7 Proteins/genetics , Papillomavirus E7 Proteins/immunology , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunologyABSTRACT
The recombinant plasmid carrying the gene encoding 3C protease of Enterovirus 71 (EV71) was constructed, the recombinant protein was then expressed and purified, the functional activity was also measured. Firstly, the 3C protease gene was inserted into pET28a vector, the constructed recombinant plasmid was transformed into E. coli BL21 (DE3) for expression under the induction of IPTG. The expressed protein was purified by affinity chromatography (Ni-NTA) and the N-terminus His-tag was cleaved by enterokinase from 3C protease. The activity of 3C protease was evaluated with fluorescent peptide substrates. It was verified by restriction analysis and sequencing that recombinant plasmid pET28a-3C was constructed correctly and functionally expressed in E. coli BL21 (DE3) resulting in the production of recombinant 3C protease with a size of 22kD. Both His-tag and non-His-tag (cleaved by enterokinase) 3C protease exhibited similar enzyme activity to 3B-3C fluorescent peptide with Km, Vmax and Kcat values of 22 microM, 434nM. Min(-1) and 0.0669 Min(-1), respectively. The optimial pH and temperature were 7.0 and 30-37 degrees C, respectively. The acquirement of recombinant purified 3C protease with high activity has paved the way of further studies on anti-viral inhibitors, structural protein assembly, vaccine development and detection methods of EV71.
Subject(s)
Cysteine Endopeptidases/genetics , Cysteine Endopeptidases/metabolism , Enterovirus A, Human/enzymology , Escherichia coli/genetics , Gene Expression , Viral Proteins/genetics , Viral Proteins/metabolism , 3C Viral Proteases , Cloning, Molecular , Cysteine Endopeptidases/chemistry , Enterovirus A, Human/genetics , Escherichia coli/metabolism , Kinetics , Viral Proteins/chemistryABSTRACT
Our study aims to evaluate whether the approach of TCRm mAb has therapeutic potential against HPV-induced tumors. In the present study, we generated a murine IgG2a mAb 6C10 specifically recognizing HPV-16-E7(49-57) epitope (RAHYNIVTF) in the polypeptides and in complex with a MHC class I molecule. Analysis of the primary structure shows that the 6C10 Ab displays a novel sequence in the CDR of the heavy chain, compared to the sequences in the Kabat database, which suggests the Ab has completed its affinity maturation. The 6C10 Ab can specifically recognize E7 and Trx-E7(30-67) protein in ELISA, and can also specifically bind to T2 cell carrying HPV-16-E7(49-57) peptide. In the TC-1 cell tumor-bearing mouse model, 6C10 exhibits tumor suppression activity when compared to the isotype control Ab. 6C10 Ab has showed tumor-inhibition potency in a mouse model and this Ab may have the prospect of cancer therapy.