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YAP/TAZ transcriptional co-activators play pivotal roles in tumorigenesis. In the Hippo pathway, diverse signals activate the MST-LATS kinase cascade that leads to YAP/TAZ phosphorylation, and subsequent ubiquitination and proteasomal degradation by SCFß-TrCP . When the MST-LATS kinase cascade is inactive, unphosphorylated or dephosphorylated YAP/TAZ translocate into the nucleus to mediate TEAD-dependent gene transcription. Hippo signaling-independent YAP/TAZ activation in human malignancies has also been observed, yet the mechanism remains largely elusive. Here, we report that the ubiquitin E3 ligase HERC3 can promote YAP/TAZ activation independently of its enzymatic activity. HERC3 directly binds to ß-TrCP, blocks its interaction with YAP/TAZ, and thus prevents YAP/TAZ ubiquitination and degradation. Expression levels of HERC3 correlate with YAP/TAZ protein levels and expression of YAP/TAZ target genes in breast tumor cells and tissues. Accordingly, knockdown of HERC3 expression ameliorates tumorigenesis of breast cancer cells. Our results establish HERC3 as a critical regulator of the YAP/TAZ stability and a potential therapeutic target for breast cancer.
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Proteínas Adaptadoras Transductoras de Señales , Neoplasias de la Mama , Humanos , Femenino , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Señalizadoras YAP , Proteínas con Repetición de beta-Transducina/genética , Proteínas con Repetición de beta-Transducina/metabolismo , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZ , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transformación Celular Neoplásica/genética , Carcinogénesis/genética , Ubiquitinación , Neoplasias de la Mama/genética , Ubiquitinas/metabolismo , Ligasas/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismoRESUMEN
Plants often simultaneously experience combined stresses rather than a single stress, causing more serious damage, but the underlying mechanisms remain unknown. Here, we identified the stress-induced IbNAC3 from sweet potato (Ipomoea batatas) as a nucleus-localized transcription activator. IbNAC3 contains a unique activation domain whose MKD sequence confers transactivation activities to multiple other TFs and is essential for the activated expression of downstream target genes. Ectopic expression of IbNAC3 conferred tolerance to single and combined salt and drought stresses in Arabidopsis (Arabidopsis thaliana), and a group of NAM, ATAF1/2, and CUC2 (NAC) TFs, including ANAC011, ANAC072, ANAC083, ANAC100, and NAP, interacted with IbNAC3, and the specific domains responsible for each interaction varied. Intriguingly, IbNAC3 repressed the interaction among the five NACs, and knockout or mutation of ANAC011 and ANAC072 dramatically impaired combined stress tolerance. IbNAC3-ANAC072 and IbNAC3-NAP modules synergistically activated the MICROTUBULE-RELATED E3 LIGASE57 (MREL57) gene. Consistently, mutation of MREL57 and overexpression of WAVE-DAM-PENED2-LIKE7, encoding a target protein of MREL57, both remarkably impaired combined stress tolerance. Moreover, transgenic plants displayed abscisic acid (ABA) hyposensitivity by directly promoting the transcription of ENHANCED RESPONSE TO ABA 1, a key negative regulator of ABA signaling. The data unravel the unique IbNAC3 TF functions as a pivotal component in combined stress tolerance by integrating multiple regulatory events and ubiquitin pathways, which is essential for developing high-tolerant plants in natural environments.
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Arabidopsis , Ipomoea batatas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Sequías , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas , Cloruro de Sodio/farmacología , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Arabidopsis/metabolismoRESUMEN
Accurate identification of tumor margins during cancer surgeries relies on a rapid detection technique that can perform high-throughput detection of multiple suspected tumor lesions at the same time. Unfortunately, the conventional histopathological analysis of frozen tissue sections, which is considered the gold standard, often demonstrates considerable variability, especially in many regions without adequate access to trained pathologists. Therefore, there is a clinical need for a multitumor-suitable complementary tool that can accurately and high-throughput assess tumor margins in every direction within the surgically resected tissue. We herein describe a high-throughput three-dimensional (3D) histological electrophoresis device that uses tumor-specific proteins to identify and contour tumor margins intraoperatively. Testing on seven cell-line xenograft models and human cervical cancer models (representing five types of tissues) demonstrated the high-throughput detection utility of this approach. We anticipate that the 3D histological electrophoresis device will improve the accuracy and efficiency of diagnosing a wide range of cancers.
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Electroforesis , Márgenes de Escisión , Neoplasias , Humanos , Neoplasias/diagnóstico , AnimalesRESUMEN
BACKGROUND: WRKY transcription factors play pivotal roles in regulating plant multiple abiotic stress tolerance, however, a genome-wide systematical analysis of WRKY genes in sweetpotato is still missing. RESULTS: Herein, 84 putative IbWRKYs with WRKY element sequence variants were identified in sweetpotato reference genomes. Fragment duplications, rather than tandem duplications, were shown to play prominent roles in IbWRKY gene expansion. The collinearity analysis between IbWRKYs and the related orthologs from other plants further depicted evolutionary insights into IbWRKYs. Phylogenetic relationships displayed that IbWRKYs were divided into three main groups (I, II and III), with the support of the characteristics of exon-intron structures and conserved protein motifs. The IbWRKY genes, mainly from the group Ib, displayed remarkable and diverse expression profiles under multiple abiotic stress (NaCl, PEG6000, cold and heat) and hormone (ABA, ACC, JA and SA) treatments, which were determined by RNA-seq and qRT-PCR assays, suggesting their potential roles in mediating particular stress responses. Moreover, IbWRKY58L could interact with IbWRKY82 as revealed by yeast two-hybrid based on the protein interaction network screening. And abiotic stress-remarkably induced IbWRKY21L and IbWRKY51 were shown to be localized in the nucleus and had no transactivation activities. CONCLUSION: These results provide valuable insights into sweetpotato IbWRKYs and will lay a foundation for further exploring functions and possible regulatory mechanisms of IbWRKYs in abiotic stress tolerance.
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Ipomoea batatas , Factores de Transcripción , Factores de Transcripción/metabolismo , Genoma de Planta , Filogenia , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Estrés Fisiológico/genética , Familia de Multigenes , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismoRESUMEN
BACKGROUND: The plant-specific GRAS transcription factors play pivotal roles in various adverse environmental conditions. Numerous GRAS genes have been explored and characterized in different plants, however, comprehensive survey on GRASs in sweetpotato is lagging. RESULTS: In this study, 72 putative sweetpotato IbGRAS genes with uneven distribution were isolated on 15 chromosomes and classified into 12 subfamilies supported by gene structures and motif compositions. Moreover, both tandem duplication and segmental duplication events played critical roles in the expansion of sweetpotato GRAS genes, and the collinearity between IbGRAS genes and the related orthologs from nine other plants further depicted evolutionary insights into GRAS gene family. RNA-seq analysis under salt stress and qRT-PCR detection of 12 selected IbGRAS genes demonstrated their significant and varying inductions under multiple abiotic stresses (salt, drought, heat and cold) and hormone treatments (ABA, ACC and JA). Consistently, the promoter regions of IbGRAS genes harbored a series of stress- and hormone-associated cis-acting elements. Among them, IbGRAS71, the potential candidate for breeding tolerant plants, was characterized as having transactivation activity in yeasts, while IbGRAS-2/-4/-9 did not. Moreover, a complex interaction relationship between IbGRASs was observed through the interaction network analysis and yeast two-hybrid assays. CONCLUSIONS: Our results laid a foundation for further functional identifications of IbGRAS genes, and multiple members may serve as potential regulators for molecular breeding of tolerant sweetpotato.
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Ipomoea batatas , Factores de Transcripción , Regulación de la Expresión Génica de las Plantas , Hormonas , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Familia de Multigenes , Filogenia , Fitomejoramiento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
With the rapid development of immunotherapy, the efficacy and feasibility of neoadjuvant immunotherapy for early resectable non-small-cell lung cancer (NSCLC) has been demonstrated. However, there are still difficulties and controversies in evaluating the efficacy of neoadjuvant immunotherapy. In our report, we described a 43-year-old female patient who was diagnosed with stage IIIA (cT1N2M0) pulmonary adenocarcinoma. After two cycles of neoadjuvant immunotherapy (sintilimab) combined with chemotherapy, according to imaging evaluation, the efficacy of the primary lesion was evaluated as stable disease and the mediastinal lymph nodes were evaluated as partial response. However, the postoperative pathological evaluation showed the primary lesion was pathological complete response and the mediastinal lymph nodes were major pathological response. This indicated that neoadjuvant chemo-immunotherapy was effective for both primary and mediastinal lymph nodes, but regression of the lesions was not synchronous. This study provided a complete process of neoadjuvant treatment, illustrating the effectiveness and safety of neoadjuvant chemo-immunotherapy to a certain extent. It is also suggested that the evaluation of neoadjuvant immunotherapy should be combined with imaging and pathology, and the primary tumor and lymph nodes should be evaluated, respectively.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Femenino , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Terapia Neoadyuvante , Estadificación de NeoplasiasRESUMEN
BACKGROUND: Renal tubulointerstitial fibrosis is known to occur as a result of epithelial cell transformation into myofibroblasts via the epithelial-to-mesenchymal transition (EMT) process. It has been reported that macrophages, regulatory T (Treg) cells, and gamma delta T (γδ T) cells can promote fibrosis via EMT in vivo. OBJECTIVE: Our study intended to detect whether thymocytes can induce renal tubular cells to undergo the EMT. METHODS: Rat thymocytes were activated by phytohemagglutinin and concanavalin A. The rat renal tubular epithelial cells (NRK-52E) were incubated in a conditioned medium harvested from activated thymocytes or co-cultured with freshly isolated thymocytes for 48 hours. Real-time reverse transcription-polymerase chain reaction, immunofluorescence, and western blotting analysis were used to test the expression of the epithelial and mesenchymal markers in NRK-52E cells. Scratch assay was designed to test the cell migration abilities of NRK-52E cells. Student's t test and oneway analysis of variance test were used for statistical analysis. RESULTS: The combined stimulation with phytohemagglutinin and concanavalin A activated the primary isolated rat thymocytes. After treatment with conditioned medium or freshly isolated thymocytes, the expression levels of cytokeratin 19 and E-cadherin were downregulated in NRK-52E cells, while the mRNA and protein expression levels of alpha-smooth muscle actin, desmin, and vimentin were upregulated (P < 0.05). We found that the cell migration abilities of the induced NRK-52E cells were significantly improved. CONCLUSIONS: Both activated rat thymocytes (more percentage of CD8+ T cells) and freshly isolated thymocytes have promoting effects on the EMT of NRK-52E cells.
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Hydrodynamic behaviors of bubble stream flow in fractal tree-shaped microchannels is investigated numerically based on a two-dimensional volume of fluid (VOF) method. Bubble breakup is examined in each level of bifurcation and the transition of breakup regimes is discussed in particular. The pressure variations at the center of different levels of bifurcations are analyzed in an effort to gain further insight into the underlying mechanism of bubble breakup affected by multi-levels of bifurcations in tree-shaped microchannel. The results indicate that due to the structure of the fractal tree-shaped microchannel, both lengths of bubbles and local capillary numbers decrease along the microchannel under a constant inlet capillary number. Hence the transition from the obstructed breakup and obstructed-tunnel combined breakup to coalescence breakup is observed when the bubbles are flowing into a higher level of bifurcations. Compared with the breakup of the bubbles in the higher level of bifurcations, the behaviors of bubbles show stronger periodicity in the lower level of bifurcations. Perturbations grow and magnify along the flow direction and the flow field becomes more chaotic at higher level of bifurcations. Besides, the feedback from the unequal downstream pressure to the upstream lower level of bifurcations affects the bubble breakup and enhances the upstream asymmetrical behaviors.
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Fractales , Hidrodinámica , Técnicas Analíticas Microfluídicas , Simulación por Computador , Diseño de Equipo , Técnicas Analíticas Microfluídicas/instrumentación , PresiónRESUMEN
The distribution and diffusion behaviors of microscopic particles at fluorobenzene-water and pentanol-water interfaces are investigated using molecular dynamics simulation. The influences of Na+/Cl- ions and the steric effects of organic molecules are examined. The concentration distributions of different species, the orientations of oil molecules at the interface, and oil-water interface morphology as well as the diffusion behaviors of water molecules are explored and analyzed. The results indicate that a few fluorobenzene molecules move into the water phase influenced by Na+/Cl- ions, while the pentanol molecules at the interface prefer orientating their hydrophilic groups toward the water phase due to their large size. The water molecules more easily burst into the pentanol phase with larger molecular spaces. As the concentration of ions in the water phase increases, more water molecules enter into the pentanol molecules, leading to larger interface roughness and interface thickness. In addition, a lower diffusion coefficient for water molecules at the fluorobenzene-water interface are observed when introducing Na+/Cl- ions in the water phase, while for the pentanol-water system, the mobility of interfacial water molecules are enhanced with less ions and inhibited with more ions.
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Fluorobencenos/química , Pentanoles/química , Agua/química , Cloruros/química , Difusión , Modelos Moleculares , Simulación de Dinámica Molecular , Sodio/químicaRESUMEN
Aneurysms of the aortic sinus are well-known clinical entities that can bulge into adjacent heart chambers or vessels. They usually reside in the right ventricle and very rarely bulge into the left ventricle causing mitral valve deformation. A 47-year-old man was admitted for shortness of breath and chest pain after exertion. He was diagnosed with a noncoronary sinus of Valsalva aneurysm bulging into the mitral valve's anterior leaflet. The aortic valve and mitral valve annulus were severely damaged and irreparable. A Bentall procedure and mechanical mitral valve replacement were performed. The patient recovered uneventfully and was discharged 11 days later.
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Aneurisma de la Aorta/diagnóstico por imagen , Rotura de la Aorta/diagnóstico por imagen , Ecocardiografía , Ventrículos Cardíacos/diagnóstico por imagen , Válvula Mitral/diagnóstico por imagen , Seno Aórtico/diagnóstico por imagen , Aneurisma de la Aorta/complicaciones , Aneurisma de la Aorta/cirugía , Rotura de la Aorta/complicaciones , Rotura de la Aorta/cirugía , Prótesis Valvulares Cardíacas , Ventrículos Cardíacos/cirugía , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral/patología , Válvula Mitral/cirugía , Seno Aórtico/cirugíaRESUMEN
AIM: Cognitive decline is thought to be more prevalent in elderly persons with periodontitis. Greater adherence to Healthy Eating Index (HEI)-2015 has been reported to improve cognitive function in the elderly population. However, whether the benefits of HEI-2015 on cognitive function apply to elderly patients with periodontitis remains unknown. METHODS: This is a cross-sectional study based on the National Health and Nutrition Examination Survey (NHANES). The data were extracted from database 2011-2014. Cognitive function was measured through the Consortium to Establish a Registry for Alzheimer's Disease battery for immediate recall (CERAD-WL) and delayed recall (CERAD-DR), Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST). The data of HEI-2015 were acquired from 24-hour dietary recalls. Weighted linear regression models were performed to investigate the association between HEI-2015 and cognitive function in elderly patients with periodontitis. The associations were further investigated in subgroups of sex, cardiovascular disease status, and depression status. RESULTS: A total of 1862 participants were included, and 1223 of them had periodontitis. Periodontitis was negatively associated with cognitive function (ß = -0.45; 95% confidence interval [CI], -0.87 to -0.03). No statistically significant relationship was observed between HEI-2015 and cognitive function (ß = 0.33; 95% CI, -0.02 to 0.69). Low HEI-2015 score was associated with high odds of cognitive decline in patients with periodontitis (ß = -0.73; 95% CI, -1.25 to -0.21; P for trend = .01). Higher HEI-2015 was related to the lower incidence of cognitive function decline in patients with periodontitis who were female (ß = -0.53; 95% CI, -1.03 to -0.03), had a socioeconomic status from 0 to 3 (ß = -0.55; 95% CI, -1.00 to -0.09), did not have cardiovascular disease (ß = -0.60; 95% CI, -1.14 to -0.05), and did not have depression (ß = -0.57; 95% CI, -1.11 to -0.03). CONCLUSIONS: Greater HEI-2015 adherence may improve cognitive function amongst elderly patients with periodontitis. Further studies are needed to investigate this putative association in elderly persons with periodontitis.
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Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, benign neoplasm of neural crest origin that predominantly involves the craniofacial region, involvement of the epididymis being extremely rare, with about 30 cases reported. We report an unusual case of a 5-month-old male with MNTI in the epididymis. The patient underwent orchiectomy. Half a year later, there was no sign of recurrence. Whether preoperative examination or intraoperative frozen examination, the tumor may easily be misdiagnosed as malignancy. Melanotic neuroectodermal tumor of infancy should be included in differential diagnosis in infants presenting with fast-growing scrotal swelling.
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Tumor Neuroectodérmico Melanótico , Lactante , Masculino , Humanos , Tumor Neuroectodérmico Melanótico/diagnóstico , Tumor Neuroectodérmico Melanótico/cirugía , Epidídimo , Pelvis , Diagnóstico Diferencial , OrquiectomíaRESUMEN
Early detection of pancreatic adenocarcinoma (PAAD) remains a pressing clinical problem. Information on the clinical prognostic value of mitochondrial fusion-related genes in PAAD remains limited. In this study, we investigated mitochondrial fusion-related genes of PAAD to establish an optimal signature plate for the early diagnosis and prognosis of PAAD. The cancer genome atlas database was used to integrate the Fragments Per Kilobase Million data and related clinical data for patients with PAAD. Least absolute shrinkage and selection operator regression, cox regression, operating characteristic curves, and cBioPortal database was used to evaluate model performance, assess the prognostic ability and sensitivity. The levels of immune infiltration were compared by CIBERSORT, QUANTISEQ, and EPIC. Chemotherapy sensitivity between the different risk groups was compared by the Genomics of Drug Sensitivity in Cancer database and the "pRRophetic" R package. At last, a total of 4 genes were enrolled in multivariate Cox regression analysis. The risk-predictive signature was constructed as: (0.5438â ×â BAK1)â +â (-1.0259â ×â MIGA2)â +â (1.1140â ×â PARL)â +â (-0.4300â ×â PLD6). The area under curve of these 4 genes was 0.89. Cox regression analyses indicates the signature was an independent prognostic indicator (Pâ <â .001, hazard ratio [HR]â =â 1.870, 95% CIâ =â 1.568-2.232). Different levels of immune cell infiltration in the 2 risk groups were observed using the 3 algorithms, with tumor mutation load (Pâ =â .0063), tumor microenvironment score (Pâ =â .01), and Tumor Immune Dysfunction and Exclusion score (Pâ =â .0012). The chemotherapeutic sensitivity analysis also revealed that the half-maximal inhibitory concentration of 5-fluorouracil (Pâ =â .0127), cisplatin (Pâ =â .0099), docetaxel (Pâ <â .0001), gemcitabine (Pâ =â .0047), and pacilataxel (Pâ <â .0001) were lower in the high-risk groups, indicating that the high-risk group patients had a greater sensitivity to chemotherapy. In conclude, we established a gene signature plate comprised of 4 mitochondrial fusion related genes to facilitate early diagnosis and prognostic prediction of PAAD.
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Adenocarcinoma , Biomarcadores de Tumor , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Pronóstico , Adenocarcinoma/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Biomarcadores de Tumor/genética , Masculino , Femenino , Persona de Mediana Edad , Dinámicas Mitocondriales/genética , Anciano , Modelos de Riesgos Proporcionales , Detección Precoz del Cáncer/métodosRESUMEN
With the advancement of micro- and nanomanufacturing technologies, electronic components and chips are increasingly being miniaturized. To automatically identify their packaging materials for ensuring the reliability of ICs, a hybrid deep learning framework termed as CNN-transformer interaction (CTI) model is designed on IC packaging images in this paper, in which several cascaded CTI blocks are designed to bidirectionally capture local and global features from the IC packaging image. Each CTI block involves a CNN branch with two designed convolutional neural networks (CNNs) for CNN local features and a transformer branch with two transformers for transformer global features and transformer local-window features. A bidirectional interaction mechanism is designed to interactively transfer the features in channel and spatial dimensions between the CNNs and transformers. Experimental results indicate that the hybrid framework can recognize three types of IC packaging materials with a good performance of 96.16% F1-score and 97.92% accuracy, which is superior to some existing deep learning methods.
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The trace elements present in breast milk play a vital role in the growth and development of infants. Nevertheless, numerous studies have reported the presence of toxic metal contamination in breast milk from various countries and regions, which poses potential risks to breastfed infants. This article aimed to investigate the characteristics of trace elements in breast milk and explore the relationship between breast milk and diet in Dalian, a coastal city in northeastern China. Breast milk samples and representative local food samples were collected from Dalian for research. The results revealed that 57 % of breast milk samples significantly exceeded the WHO safety limit (0.6 µg/L) for arsenic, with a measured mean value of 0.96 µg/L. Moreover, the levels of chromium (mean value: 2.63 µg/L) in 34 % of breast milk samples exceed the WHO recommended safety level (chromium: 1.5 µg/L). Aquatic foods accounted for 60 % to 90 % of the total intake of arsenic, cadmium, vanadium, mercury, and lead. The Spearman correlation analysis demonstrated strong positive correlations among breast milk metal elements, including copper-zinc (r = 0.68) and nickelchromium (r = 0.89). Furthermore, the food-to-milk accumulation factors (FMAF) of strontium, nickel, arsenic, vanadium, cadmium, and mercury were relatively low (median values <0.005). While the FMAF values for chromium and lead were higher, with median values of 0.038 and 0.07, respectively. The results indicated potential risks of the toxic metal arsenic in breast milk from Dalian, China for breastfed infants. Therefore, continuous monitoring of breast milk for toxic metals and foodborne contamination is necessary.
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Intoxicación por Arsénico , Arsénico , Mercurio , Metales Pesados , Oligoelementos , Lactante , Femenino , Humanos , Cadmio/análisis , Arsénico/análisis , Leche Humana/química , Níquel/análisis , Oligoelementos/análisis , Vanadio/análisis , Mercurio/análisis , Cromo/análisis , Intoxicación por Metales Pesados , Ingestión de Alimentos , Metales Pesados/análisisRESUMEN
Microenvironment regulation near the catalyst surface plays a critical role in heterogeneous electrocatalytic reactions. The local concentration of reactants and intermediates significantly affects the reaction kinetics and product selectivity. Herein, we propose an innovative strategy of utilizing the spatial confinement effect in a sandwich-structured C/Cu/C assembly to regulate kinetic mass transport during the electrocatalytic CO2 reduction reaction. The sandwich C/Cu/C assembly catalyst was successfully prepared using a simple bidirectional freezing and freeze-drying method. The sandwich structure changes the free diffusion pathway of the CO intermediate within the sandwich interlayer and helps confine CO with locally increased CO concentration near the catalyst surface, which in turn promotes C-C coupling and thus improves the reaction activity and doubles the C2 product selectivity compared to its disordered mixture counterpart. This kinetics regulation in the sandwich structure may provide a new insight into the catalyst design and inspire the understanding of the structure-performance relationship in electrocatalysis.
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As a novel technique with a wide range of applications, microbial fuel cell (MFC) could simultaneously remove organic contaminants and heavy metals in complex wastewater, despite striking differences in physicochemical properties of these contaminant. But its wastewater treatment efficiency is restricted by its lower generation performance. However, approaches for the modification of MFCs' cathode with appropriate catalyst could effectively overcome this limitation. Herein, a new-type efficient cathode catalyst was invented through modifying natural molybdenite via one-step oxidation method. In this case, molybdenite had many changes in morphology (wave-shaped bending, fragmentation and decrescent diameter) during oxidation modification process, and oxidation-modified molybdenite could provide much more active sites for the cathode. After applying this novel cathode catalyst, the electric generation capacity of MFC system increased by 5.08 times, and its simultaneous degradation efficiency of methyl blue (MB) and Cr (VI) increased by 3.35 times (compared with graphite cathode MFC). This study provides a novel low-carbon and environmentally friendly way to prepare high efficiency cathode catalyst materials and provides a new idea of simultaneous purification for organic and metallic pollutants from complex wastewater.
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Fuentes de Energía Bioeléctrica , Metales Pesados , Electricidad , Aguas Residuales , ElectrodosRESUMEN
The microbial fuel cell (MFC) is a promising bio-electrochemical technology that enables simultaneous electricity generation and effluent purification. Harnessing solar energy to provide sustainable power for MFC operation holds great potential. In this study, a semiartificial photosynthetic self-circulating MFC ecosystem is successfully established through the collaboration of electrogenic microorganisms and photosynthetic algae. The ecosystem can operate continuously without carbon sources and produces a voltage of 150 mV under irradiation. The irradiation doubles the maximum power density of the ecosystem, reaching 8.07 W/m2 compared to dark conditions. The results of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) suggest a higher diffusion capacity or faster electron replenishment ability within the ecosystem. Furthermore, the capacity of ecosystem for removing chromium (Cr(VI)) has been investigated comprehensively. Under irradiation, the ecosystem demonstrates a 2.25-fold increase in Cr(VI) removal rate compared to dark conditions. Finally, the results of 16S rRNA amplicon sequencing indicates an increase in the relative abundance of strict and facultative aerobic electroactive bacteria in the ecosystem, including Citrobacter (21 %), Bacillus (15 %) and Enterococcus (6 %). The ecosystem offers a novel, self-sustaining approach to address the challenges of energy recovery and environmental pollution.
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Fuentes de Energía Bioeléctrica , Ecosistema , ARN Ribosómico 16S , Electricidad , Fuentes de Energía Bioeléctrica/microbiología , Bacterias/genética , ElectrodosRESUMEN
Microbial-mineral interaction has a broad application prospect in the field of environmental remediation of organic pollutants. However, the disadvantages of long repair cycle and low repair rate limit its industrial application. In this study, natural hematite was used as an auxiliary material for soil remediation in a bio-electrochemical system. It was found that the power density of soil microbial fuel cell (SMFC) system composed of 2.0 mm hematite was 2.889 mW/m2, which is 2.7 times compared with the blank group (1.068 mW/m2) in the particle size optimization experiment. A similarly increased power density (1.068 to 2.467 mW/m2) was observed when the hematite content changed from 0 to 20% in the concentration optimization experiment. Under 20% and 2.0-mm hematite condition, the phenol removal rate was closed to 99% after 7 days, which is 1.9-folds compared with blank control (53%). These results suggest that addition of hematite enhances soil porosity and conductivity, and increases the number of electron acceptors in soil. These findings inspire that this economic and abundant natural mineral is expected to be a potential auxiliary material in the field of soil organic pollutant purification, and expand the understanding of interactions between hematite and microorganisms in nature.