RESUMEN
The development of efficient and durable non-precious hydrogen evolution reaction (HER) catalysts for scaling up alkaline water/seawater electrolysis is highly desirable but challenging. Amorphous-crystalline (A-C) heterostructures have garnered attention due to their unusual atomic arrangements at hetero-interfaces, highly exposed active sites, and excellent stability. Here, a heterogeneous synthesis strategy for constructing A-C non-homogeneous interfacial centers of electrocatalysts on nanocages is presented. Isolated PdCo clusters on nanoscale islands in conjunction with Co3S4 A-C, functioning as a bifunctional site "island-sea" synergy, enable the dynamic confinement design of metal active atoms, resulting in excellent HER catalytic activity and durability. The hierarchical structure of hollow porous nanocages and nanoclusters, along with their large surface area and multi-dimensional A-C boundaries and defects, provides the catalyst with abundant active centers. Theoretical calculations demonstrate that the combination of PdCo and Co3S4 regulates the redistribution of interface electrons effectively, promoting the sluggish water-dissociation kinetics at the cluster Co sites. Additionally, PdCo-Co3S4 heterostructure nanocages exhibit outstanding HER activity in alkaline seawater and long-term stability for 100 h, which can be powered by commercial silicon solar cells. This finding significantly advances the development of alkaline seawater electrolysis for large-scale hydrogen production.
RESUMEN
The bio-removal efficiency of sulfamethoxazole (SMX) from wastewater is usually very poor. In this paper a new efficient method to biodegrade SMX was reported. The SMX biodegradation efficiency by Paracoccus denitrificans was observed to be remarkably enhanced from 48.9% to 94.2% after Shewanella oneidensis MR-1 addition. The mechanisms investigation revealed that P. denitrificans was the dominant microbe for SMX biodegradation. Although SMX biodegradation by S. oneidensis MR-1 alone was negligible, its presence advanced NADH generation. The proteomics assay revealed that the expression of key proteins relevant with complex I and III and cytochrome c in electron transfer chain were increased due to P. denitrificans acquiring iron from periplasm to cytoplasm being improved. In addition, the extracellular electron transfer capability was enhanced as S. oneidensis MR-1 not only produced flavin, but caused P. denitrificans to secret more extracellular polymeric substances. Further investigation indicated that the expression of key enzymes related to electron consumption in SMX biodegradation was up-regulated. Based on these findings, the pathways of S. oneidensis MR-1 promoting SMX biodegradation were proposed. As all nitrate could be removed with almost no nitrite accumulation, this study would also provide an attractive way for simultaneous bio-removal of multiple pollutants from wastewater.
Asunto(s)
Shewanella , Sulfametoxazol , Biodegradación Ambiental , Transporte de Electrón , Electrones , NADRESUMEN
Recovering carboxylic acids derived from organic wastes from fermentation broth is challenging. To provide a reference for future study and industrial application, this review summarized recent advances in recovery technologies of carboxylic acids including precipitation, extraction, adsorption, membrane-based processes, etc. Meanwhile, applications of recovered carboxylic acids are summarized as well to help choose suitable downstream processes according to purity requirement. Integrated processes are required to remove the impurities from the complicated fermentation broth, at the cost of loss and expense. Compared with chemical processes, biological synthesis is better options due to low requirements for the substrates. Generally, the use of toxic agents, consumption of acid/alkaline and membrane fouling hamper the sustainability and scale-up of the downstream processes. Future research on novel solvents and materials will facilitate the sustainable recovery and reduce the cost of the downstream processes.
Asunto(s)
Ácidos , Ácidos Carboxílicos , Adsorción , Fermentación , SolventesRESUMEN
Waste sorting is an effective means of enhancing resource or energy recovery from municipal solid waste (MSW). Waste sorting management system is not limited to source separation, but also involves at least three stages, i.e., collection and transportation (C&T), pretreatment, and resource utilization. This review focuses on the whole process of MSW management strategy based on the waste sorting perspective. Firstly, as the sources of MSW play an essential role in the means of subsequent valorization, the factors affecting the generation of MSW and its prediction methods are introduced. Secondly, a detailed comparison of approaches to source separation across countries is presented. Constructing a top-down management system and incentivizing or constraining residents' sorting behavior from the bottom up is believed to be a practical approach to promote source separation. Then, the current state of C&T techniques and its network optimization are reviewed, facilitated by artificial intelligence (AI) and the Internet of Things technologies. Furthermore, the advances in pretreatment strategies for enhanced sorting and resource recovery are introduced briefly. Finally, appropriate methods to valorize different MSW are proposed. It is worth noting that new technologies, such as AI, show high application potential in waste management. The sharing of (intermediate) products or energy of varying processing units will inject vitality into the waste management network and achieve sustainable development.
RESUMEN
Ovarian cancer remains the sixth most frequently occurring cancer in women worldwide. Long noncoding RNAs (lncRNAs) are capable of regulating gene expression, and thus, participating in a wide range of biological functions and disease processes including cancer development. Our work suggests that lncRNA TMPO antisense RNA 1 (TMPO-AS1) represents an oncogenic lncRNA in ovarian cancer and presents a novel mechanism involving transcription factor E2F transcription factor 6 (E2F6) and lipocalin-2 (LCN2). We identified upregulated lncRNA TMPO-AS1 in ovarian cancer tissues and cells. siRNA-mediated silencing of lncRNA TMPO-AS1 restrained the aggressiveness of ovarian cancer cells and their pro-angiogenic ability, and reduced the expression of LCN2. LncRNA TMPO-AS1 was found to interact with E2F6, a transcriptional repressor that could bind to the promoter region of LCN2 gene. In addition, silencing of E2F6 or overexpression of LCN2 restored the aggressiveness of ovarian cancer cells and their pro-angiogenic ability following siRNA-mediated silencing of lncRNA TMPO-AS1. Taken together, we demonstrated lncRNA TMPO-AS1 could potentially promote LCN2 transcriptional activity by binding to transcription factor E2F6, and thus, stimulated the progression of ovarian cancer. These findings underscore a possible alternative therapeutic strategy for ovarian cancer treatment.
Asunto(s)
Carcinogénesis/genética , Regulación Neoplásica de la Expresión Génica , Lipocalina 2/genética , Neoplasias Ováricas/genética , ARN Largo no Codificante/genética , Animales , Línea Celular Tumoral , Factor de Transcripción E2F6/genética , Factor de Transcripción E2F6/metabolismo , Femenino , Humanos , Lipocalina 2/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Ováricas/metabolismo , Interferencia de ARN , Carga Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto/métodosRESUMEN
Long noncoding RNAs (lncRNAs) have been implicated in the regulation of resistance to radiotherapy in cervical cancer, which is a type of gynecological disease with high mortality in women around the world. Hence, our purpose is to delineate the involvement of LINC00958 in regulating cell sensitivity to radiotherapy in cervical cancer. LINC00958 expression in cervical cancer was assayed, followed by verification of the relationship among LINC00958, microRNA-5095 (miR-5095) and ribonucleotide reductase subunit M2 (RRM2). Hela cells were transduced with up-/downregulation of miR-5095 or RRM2, or LINC00958 silencing, respectively, and then treated with or without a 6 Gy dose of X-ray irradiation. Then the cell proliferation, apoptosis, survival fraction rate, as well as sensitivity to radiotherapy, were assessed. Finally, xenograft tumor in nude mice was established by transplanting Hela cells transfected with sh-LINC00958 and irradiated with 6 Gy of X-ray. High expression of LINC00958 was revealed in The Cancer Genome Atlas and Gene Expression Profiling Interactive Analysis, as well as in radiation-resistant patients, which was associated with lower sensitivity to radiotherapy in cervical cancer. Moreover, cervical cancer patients with higher LINC00958 expression exhibited a shorter overall survival according to Kaplan-Meier analysis. In addition, LINC00958 could regulate the expression of RRM2 by competing for miR-5095. A combination of radiotherapy with LINC00958 silencing, RRM2 downregulation or miR-5095 overexpression was found to inhibit cervical cancer cell proliferation and tumor growth, while promoting cell apoptosis both in vitro and in vivo. Collectively, our results suggest that LINC00958 could regulate RRM2 by competing to miR-5095, which regulates cell sensitivity to radiotherapy in cervical cancer.
Asunto(s)
Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Tolerancia a Radiación/genética , Ribonucleósido Difosfato Reductasa/genética , Neoplasias del Cuello Uterino/genética , Animales , Apoptosis/genética , Proliferación Celular/genética , Femenino , Células HeLa , Xenoinjertos , Humanos , Ratones , Ratones DesnudosRESUMEN
Nitidine chloride (NC) exhibits anti-tumor properties in various types of tumor. However, to the best of our knowledge there is no previous evidence of NC involvement in the apoptosis or proliferation of ovarian cancer cells and the underlying molecular mechanisms. The present study aimed to investigate the influence of NC on the viability and apoptosis of ovarian cancer cells and the synergistic effect NC and doxorubicin (DOX) may have on ovarian cancer cells. The viability and proliferation of ovarian cancer cells were examined using a methyl thiazolyl tetrazolium assay and 3H-thymidine incorporation assay. The apoptotic rate of ovarian cancer cells was detected by flow cytometry. The expression of apoptosisassociated proteins and Akt serine/threonine kinase 1 (Akt) were determined by western blot analysis following NC treatment. The inhibitory effect of NC on the proliferation of ovarian cancer cells was demonstrated in a time and dosedependent manner. The pro-apoptotic effect of NC on ovarian cancer cells was also observed. It was determined that NC significantly downregulated the protein expression levels of Bcell CLL/lymphoma 2 (Bcl-2) and upregulated the expression of Bcl2associated X protein, p53, caspase3 and 9. NC suppressed Akt phosphorylation. Additionally, the present study demonstrated that the effect of NC on the proliferation and apoptosis of ovarian cancer cells was Aktdependent by using the phosphatidylinositol-4,5-bisphosphate 3-kinase/Akt signaling pathway inhibitor, LY294002. NC exhibited a synergistic inhibitory effect on the viability of ovarian cancer cells when combined with DOX. The current study demonstrated that NC inhibited the proliferation and induced the apoptosis of ovarian cancer cells via the Akt signaling pathway and highlighted its potential clinical application for the treatment of ovarian cancer.
Asunto(s)
Antibióticos Antineoplásicos/farmacología , Benzofenantridinas/farmacología , Doxorrubicina/farmacología , Neoplasias Ováricas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Benzofenantridinas/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Ováricas/genética , FosforilaciónRESUMEN
Hollow silica spheres with round mesoporous shells were synthesized by core-shell template method, using monodispersed cationic polystyrene particles as core, and TEOS (tetraethoxysilane) as the silica source to form shell. After calcination at 550°C, uniform spheres with a thin shell of silica and hollow interior structures. Transmission electron microscopy results showed that the size of the spheres is about 700 nm in diameter with narrow distribution. In addition, the spheres have a high surface area of 183 m(2)/g. The spheres were subsequently used as silver-loading substrates and the silver loaded spheres were tested in antimicrobial study against gram negative bacteria Eschrichia coli in vitro. The hollow silica-Ag spheres proved significantly higher antibacterial efficacy against E. coli as compared to that of the common silica-Ag particles.
Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Dióxido de Silicio/química , Plata/química , Plata/farmacología , Cationes/química , Composición de Medicamentos , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanopartículas , Silanos/químicaRESUMEN
The anaerobic degradation of quinoline, isoquinoline and 2-methylquinoline was investigated under nitrate-reducing conditions with acclimated activated sludge. Quinoline was completely transformed during degradation with an optimum COD/NO(3)-N ratio of 7. Isoquinoline and 2-methylquinoline were also completely transformed; however, nitrate consumption was much lower with the optimum COD/NO(3)-N ratios being in the ranges of 83-92 and 21-26, respectively. GC-MS analyses showed that during degradation, quinoline and isoquinoline were transformed by hydroxylation into 2(1H)-quinolinone and 1(2H)-isoquinolinone, respectively. While quinoline was completely mineralized, only 92% of isoquinoline was mineralized, and 1(2H)-isoquinolinone remained in the effluent. 2-Methylquinoline was transformed by hydrogenation to 1,2,3,4-tetrahydro-2-methyl-quinoline, and further degradation resulted in cleavage of the heterocyclic ring leaving 4-ethyl-benzenamine. Both the metabolites remained in the effluent, resulting in the low mineralization of 2-methylquinoline (58%). This is the first time that 2-methylquinoline is observed degradable under denitrifying conditions, and its metabolites are identified.
Asunto(s)
Isoquinolinas/química , Nitratos/química , Quinaldinas/química , Quinolinas/química , Aguas del Alcantarillado/análisis , Biodegradación Ambiental , Cromatografía por Intercambio Iónico , Cromatografía de Gases y Espectrometría de Masas , Espectrometría de Masas , Minerales/análisis , Oxidación-Reducción , Eliminación de Residuos LíquidosRESUMEN
Heating at 100 degrees C for 5-10 min is a common method for treating wastewater containing recombinant DNA in many bio-laboratories in China. In this experiment, plasmid pET-28b was used to investigate decay efficiency of waste recombinant DNA during thermo-treatment. The results showed that the decay half-life of the plasmid was 2.7-4.0 min during the thermo-treatment, and even heating for 30 min the plasmids still retained some transforming activity. Low pH promoted the decay of recombinant DNA, but NaCl, bovine serum albumin and EDTA, which existed in the most wastewater from bio-laboratories, protected DNA from degradation. Thus, the decay half-life of plasmid DNA may be longer than 2.7-4.0 min practically. These results suggest that the effectiveness of heating at 100 degrees C for treating waste recombinant DNA is low and a gene pollution risk remains when those thermo-treated recombinant DNAs are discharged into the environment. Therefore other simple and effective methods should be developed.
Asunto(s)
ADN Recombinante/química , Calefacción/métodos , Eliminación de Residuos Líquidos/métodos , ADN Recombinante/análisis , Interacciones Farmacológicas , Ácido Edético/química , Semivida , Concentración de Iones de Hidrógeno , Incineración , Plásmidos/química , Albúmina Sérica Bovina/química , Cloruro de Sodio/químicaRESUMEN
The discharge of recombinant DNA waste from biological laboratories into the eco-system may be one of the pathways resulting in horizontal gene transfer or "gene pollution". Heating at 100 degrees C for 5-10 min is a common method for treating recombinant DNA waste in biological research laboratories in China. In this study, we evaluated the effectiveness and the safety of the thermo-treatment method in the disposal of recombinant DNA waste. Quantitative PCR, plasmid transformation and electrophoresis technology were used to evaluate the decay/denaturation efficiency during the thermo-treatment process of recombinant plasmid, pET-28b. Results showed that prolonging thermo-treatment time could improve decay efficiency of the plasmid, and its decay half-life was 2.7-4.0 min during the thermo-treatment at 100 degrees C. However, after 30 min of thermo-treatment some transforming activity remained. Higher ionic strength could protect recombinant plasmid from decay during the treatment process. These results indicate that thermo-treatment at 100 degrees C cannot decay and inactivate pET-28b completely. In addition, preliminary results showed that thermo-treated recombinant plasmids were not degraded completely in a short period when they were discharged into an aquatic environment. This implies that when thermo-treated recombinant DNAs are discharged into the eco-system, they may have enough time to re-nature and transform, thus resulting in gene diffusion.
Asunto(s)
ADN Recombinante/aislamiento & purificación , Calefacción , Laboratorios , Investigación , Administración de la Seguridad/métodos , Administración de Residuos/métodos , China , ADN Recombinante/metabolismo , ADN Recombinante/toxicidad , Electroforesis , Concentración Osmolar , Plásmidos , Reacción en Cadena de la Polimerasa , Factores de TiempoRESUMEN
Analysis of Cu2+ adsorption on cell surface of a Gram-negative bacterium P. putida 5-x was carried out. Isolated cell envelopes possess fivefold more Cu2+ adsorption capacity than that of the fresh intact cells. Experimental results also indicate that the content of the peptidoglycan layer, the outer membrane and inner membrane in the cell envelope is in order of inner membrane > outer membrane > PEG layer, while their Cu2+ adsorption capacity is in order of PEG layer > outer membrane > inner membrane. The total contribution of the separated PEG layer material to Cu2+ adsorption is no more than 15% part, and the cell outer membrane and inner membrane contribute about 30%-35% and 25%-30% part, respectively, to Cu2+ adsorption by the cell envelope. The relatively high phospholipid content in the outer wall might result in its higher adsorption capacity to Cu2+, and leads to a higher adsorption capacity of the cell envelope of P. putida 5-x.