Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 157
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Chem Rev ; 124(8): 5119-5166, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38619540

RESUMO

Highly efficient coelectrolysis of CO2/H2O into syngas (a mixture of CO/H2), and subsequent syngas conversion to fuels and value-added chemicals, is one of the most promising alternatives to reach the corner of zero carbon strategy and renewable electricity storage. This research reviews the current state-of-the-art advancements in the coelectrolysis of CO2/H2O in solid oxide electrolyzer cells (SOECs) to produce the important syngas intermediate. The overviews of the latest research on the operating principles and thermodynamic and kinetic models are included for both oxygen-ion- and proton-conducting SOECs. The advanced materials that have recently been developed for both types of SOECs are summarized. It later elucidates the necessity and possibility of regulating the syngas ratios (H2:CO) via changing the operating conditions, including temperature, inlet gas composition, flow rate, applied voltage or current, and pressure. In addition, the sustainability and widespread application of SOEC technology for the conversion of syngas is highlighted. Finally, the challenges and the future research directions in this field are addressed. This review will appeal to scientists working on renewable-energy-conversion technologies, CO2 utilization, and SOEC applications. The implementation of the technologies introduced in this review offers solutions to climate change and renewable-power-storage problems.

2.
Langmuir ; 40(1): 193-200, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38128268

RESUMO

Oxygen interaction with the carbon surface is one of the most important topics of study in the field of material chemistry. In this work, experimental evidence for molecular oxygen dissociative chemisorption on a carbon surface at room temperature is shown for the first time. It was determined that the process occurs only on the bare carbon surface, and the quantitative description of the phenomena is possible using the Temkin model, which explains an almost linear decrease in the calorimetric heat of adsorption. The results provided by in situ infrared studies show that surface carbonyl oxides appear as intermediates of final functionality, i.e., carbonyl structures. Examining the thermal stability of surface structures shows that all surface species decompose at temperatures below 500 °C, leaving a pristine carbon surface.

3.
Environ Res ; 241: 117660, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37979928

RESUMO

Cow dung generates globally due to increased beef and milk consumption, but its treatment efficiency remains low. Previous studies have shown that riboflavin-loaded conductive materials can improve anaerobic digestion through enhance direct interspecies electron transfer (DIET). However, its effect on the practical anaerobic digestion of cow dung remained unclear. In this study, carbon cloth loaded with riboflavin (carbon cloth-riboflavin) was added into an anaerobic digester treating cow dung. The carbon cloth-riboflavin reactor showed a better performance than other two reactors. The metagenomic analysis revealed that Methanothrix on the surface of the carbon cloth predominantly utilized the CO2 reduction for methane production, further enhanced after riboflavin addition, while Methanothrix in bulk sludge were using the acetate decarboxylation pathway. Furthermore, the carbon cloth-riboflavin enriched various major methanogenic pathways and activated a large number of enzymes associated with DIET. Riboflavin's presence altered the microbial communities and the abundance of functional genes relate to DIET, ultimately leading to a better performance of anaerobic digestion for cow dung.


Assuntos
Carbono , Elétrons , Bovinos , Animais , Anaerobiose , Metano , Reatores Biológicos , Esgotos
4.
Ann Diagn Pathol ; 69: 152268, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38301396

RESUMO

BACKGROUND: Major pathological response (MPR) is proposed as a surrogate endpoint for survival in non-small cell lung cancer (NSCLC) after neoadjuvant chemoimmunotherapy. However, the criteria for estimating MPR differ between the recommendations of the International Association for the Study of Lung Cancer (IASLC) and the immune-related pathologic response criterion (irPRC). IASLC's criteria focus solely on evaluating the primary tumor, while irPRC's criteria encompass both the primary tumor and lymph node metastasis. Our objective is to compare the prognostic value of different criteria for estimating MPR. METHODS: We conducted a retrospective study on a cohort of 235 patients with NSCLC after neoadjuvant chemoimmunotherapy. The survival endpoint was event-free survival (EFS). The MPR status of each patient was evaluated using both IASLC's criteria and irPRC's criteria. The prognostic value was compared using the Area Under Curve (AUC). RESULTS: The MPR rates were 63.4 % (149/235) and 57.4 % (135/235) according to IASLC's and irPRC's criteria, respectively. Inconsistent cases, characterized by MPR status according to IASLC's criteria but non-MPR status according to irPRC's criteria, constituted 6.0 % (14/235) of the overall cohort and 15.2 % (14/92) of patients with pretreatment N positive disease. Interestingly, all inconsistent patients showed no recurrence during the study period. Although both MPR statuses according to IASLC (p = 0.00039) and irPRC (p = 0.0094) were associated with improved EFS, IASLC's criteria (AUC = 0.65) were superior to irPRC's criteria (AUC = 0.62) with a higher AUC value. CONCLUSION: IASLC's criteria for estimating MPR were superior to irPRC's criteria in predicting EFS for NSCLC after neoadjuvant chemoimmunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Terapia Neoadjuvante , Estudos Retrospectivos , Imunoterapia
5.
J Environ Manage ; 357: 120843, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38588621

RESUMO

Nitrite-dependent anaerobic methane oxidation (n-DAMO) is a novel denitrification process that simultaneously further removes and utilizes methane from anaerobic effluent from wastewater treatment plants. However, the metabolic activity of n-DAMO bacteria is relative low for practical application. In this study, conductive magnetite was added into lab-scale sequencing batch reactor inoculated with n-DAMO bacteria to study the influence on n-DAMO process. With magnetite amendment, the nitrogen removal rate could reach 34.9 mg N·L-1d-1, nearly 2.5 times more than that of control group. Magnetite significantly facilitated the interspecies electron transfer and built electrically connected community with high capacitance. Enzymatic activities of electron transport chain were significantly elevated. Functional gene expression and enzyme activities associated with nitrogen and methane metabolism had been highly up-regulated. These results not only propose a useful strategy in n-DAMO application but also provide insights into the stimulating mechanism of magnetite in n-DAMO process.


Assuntos
Óxido Ferroso-Férrico , Nitritos , Nitritos/metabolismo , Transporte de Elétrons , Anaerobiose , Metano , Elétrons , Desnitrificação , Oxirredução , Bactérias/metabolismo , Bactérias Anaeróbias/metabolismo , Nitrogênio/metabolismo , Reatores Biológicos/microbiologia
6.
Bioorg Med Chem Lett ; 95: 129487, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37734423

RESUMO

The G2019S variant of LRRK2, which causes an increase in kinase activity, is associated with the occurrence of Parkinson's disease (PD). Potent, mutation-selective, and brain penetrant inhibitors of LRRK2 can suppress the biological effects specific to G2019S-LRRK2 that cause pathogenicity. We report the discovery of a series of cyanoindane and cyanotetralin kinase inhibitors culminating in compound 34 that demonstrated selective inhibition of phosphorylation of LRRK2 in the mouse brain. These novel inhibitors may further enable the precision medicine path for future PD therapeutics.

7.
Hereditas ; 160(1): 38, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38082360

RESUMO

BACKGROUND: Dyskeratosis congenita 1 (DKC1), a critical component of telomerase complex, is highly expressed in a variety of human cancers. However, the association of DKC1 with cancer occurrence and development stages is not clear, making a pan-cancer analysis crucial. METHODS: We conducted a study using various bioinformatic databases such as TIMER, GEPIA, UALCAN, and KM plotter Analysis to examine the different expressions of DKC1 in multiple tissues and its correlation with pathological stages. Through KEGG analysis, GO enrichment analysis and Venn analysis, we were able to reveal DKC1-associated genes and signaling pathways. In addition, we performed several tests including the CCK, wound healing assay, cell cycle arrest assay, transwell assay and Sa-ß-gal staining on DKC1-deleted MDA-231 cells. RESULTS: Our study demonstrates that DKC1 has relatively low expression specificity in different tissues. Furthermore, we found that in ACC, KICH, KIRP and LIHC, the expression level of DKC1 is positively correlated with pathological stages. Conversely, in NHSC, KIRP, LGG, LIHC, MESO and SARC, we observed a negative influence of DKC1 expression level on the overall survival rate. We also found a significant positive correlation between DKC1 expression and Tumor Mutational Burden in 14 tumors. Additionally, we observed a significantly negative impact of DKC1 DNA methylation on gene expression at the promoter region in BRCA. We also identified numerous phosphorylation sites concentrated at the C-terminus of the DKC1 protein. Our GO analysis revealed a correlation between DKC1 and ribosomal biosynthesis pathways, and the common element UTP14A was identified. We also observed decreased rates of cell proliferation, migration and invasion abilities in DKC1-knockout MDA-MB-231 cell lines. Furthermore, DKC1-knockout induced cell cycle arrest and caused cell senescence. CONCLUSIONS: Our findings suggest that the precise expression of DKC1 is closely associated with the occurrence and developmental stages of cancer in multiple tissues. Depletion of DKC1 can inhibit the abilities of cancer cells to proliferate, migrate, and invade by arresting the cell cycle and inducing cell senescence. Therefore, DKC1 may be a valuable prognostic biomarker for the diagnosis and treatment of cancer in various tissues.


Assuntos
Disceratose Congênita , Neoplasias , Humanos , Prognóstico , Proteínas de Ciclo Celular/genética , Disceratose Congênita/genética , Disceratose Congênita/metabolismo , Disceratose Congênita/patologia , Neoplasias/genética , Biomarcadores , Proteínas Nucleares/genética
8.
Int J Mol Sci ; 24(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37762700

RESUMO

Liquid hydrogen carriers will soon play a significant role in transporting energy. The key factors that are considered when assessing the applicability of ammonia cracking in large-scale projects are as follows: high energy density, easy storage and distribution, the simplicity of the overall process, and a low or zero-carbon footprint. Thermal systems used for recovering H2 from ammonia require a reaction unit and catalyst that operates at a high temperature (550-800 °C) for the complete conversion of ammonia, which has a negative effect on the economics of the process. A non-thermal plasma (NTP) solution is the answer to this problem. Ammonia becomes a reliable hydrogen carrier and, in combination with NTP, offers the high conversion of the dehydrogenation process at a relatively low temperature so that zero-carbon pure hydrogen can be transported over long distances. This paper provides a critical overview of ammonia decomposition systems that focus on non-thermal methods, especially under plasma conditions. The review shows that the process has various positive aspects and is an innovative process that has only been reported to a limited extent.


Assuntos
Amônia , Gases em Plasma , Transporte Biológico , Carbono , Temperatura Baixa , Hidrogênio
9.
Int J Mol Sci ; 24(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37108801

RESUMO

YIN YANG 1 (YY1) encodes a dual-function transcription factor, evolutionary conserved between the animal and plant kingdom. In Arabidopsis thaliana, AtYY1 is a negative regulator of ABA responses and floral transition. Here, we report the cloning and functional characterization of the two AtYY1 paralogs, YIN and YANG (also named PtYY1a and PtYY1b) from Populus (Populus trichocarpa). Although the duplication of YY1 occurred early during the evolution of the Salicaceae, YIN and YANG are highly conserved in the willow tree family. In the majority of Populus tissues, YIN was more strongly expressed than YANG. Subcellular analysis showed that YIN-GFP and YANG-GFP are mainly localized in the nuclei of Arabidopsis. Stable and constitutive expression of YIN and YANG resulted in curled leaves and accelerated floral transition of Arabidopsis plants, which was accompanied by high expression of the floral identity genes AGAMOUS (AG) and SEPELLATA3 (SEP3) known to promote leaf curling and early flowering. Furthermore, the expression of YIN and YANG had similar effects as AtYY1 overexpression to seed germination and root growth in Arabidopsis. Our results suggest that YIN and YANG are functional orthologues of the dual-function transcription factor AtYY1 with similar roles in plant development conserved between Arabidopsis and Populus.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Populus , Arabidopsis/metabolismo , Populus/genética , Populus/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Arabidopsis/genética , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas , Flores/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
10.
J Environ Manage ; 340: 118001, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37105103

RESUMO

Anaerobic ammonium oxidation (Anammox) coupled with Denitrifying anaerobic methane oxidation (DAMO) is an attractive technology to simultaneously remove nitrogen and mitigate methane emissions from wastewater. However, its nitrogen removal rate is usually limited due to the low methane mass transfer efficiency, low metabolic activity and slow growth rate of functional microorganisms. In this study, GAC and Fe-modified GAC (Fe-GAC) were added into Anammox-DAMO process to investigate their effects on nitrogen removal rates and then reveal the mechanism. The results showed that after 80-day experiments, the total nitrogen removal rate was slightly improved in the presence of GAC (3.94 mg L-1·d-1), while it reached high as 16.66 mg L-1·d-1 in the presence of Fe-GAC, which was ca.17 times that of non-amended control group (0.96 mg L-1·d-1). The addition of Fe-GAC stimulated the secretion of extracellular polymeric substance (EPS), improved the electron transfer capability and promoted the production of Cytochrome C. Besides, the key functional enzyme activities (HZS, HDH and NAR) were highest in the Fe-GAC group, which were approximately 1.06-1.56 times higher than those of GAC-amended and blank control groups. Microbial community analysis showed that the abundance of the DAMO archaea (Candidatus Methanoperedens) and Anammox bacteria (Candidatus Brocadia) were remarkably increased with the addition of Fe-GAC. Functional genes associated with nitrogen removal and methane oxidation in Fe-GAC system were up-regulated. This study provides a promising strategy for achieving high rate of nitrogen removal upon Anammox-DAMO process.


Assuntos
Compostos de Amônio , Carvão Vegetal , Metano , Nitrogênio/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Desnitrificação , Oxidação Anaeróbia da Amônia , Anaerobiose , Oxirredução , Reatores Biológicos/microbiologia , Compostos de Amônio/metabolismo , Nitritos/metabolismo
11.
Small ; 18(30): e2202989, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35790070

RESUMO

High-capacity Ni-rich layered oxides are considered as promising cathodes for lithium-ion batteries. However, the practical applications of LiNi0.83 Co0.07 Mn0.1 O2  (NCM83) cathode are challenged by continuous transition metal (TM) dissolution, microcracks and mixed arrangement of nickel and lithium sites, which are usually induced by deleterious cathode-electrolyte reactions. Herein, it is reported that those side reactions are limited by a reliable cathode electrolyte interface (CEI) layer formed by implanting a nonsacrificial nitrile additive. In this modified electrolyte, 1,3,6-Hexanetricarbonitrile (HTCN) plays a nonsacrificial role in modifying the composition, thickness, and formation mechanism of the CEI layers toward improved cycling stability. It is revealed that HTCN and 1,2-Bis(2-cyanoethoxy)ethane (DENE) are inclined to coordinate with the TM. HTCN can stably anchor on the NCM83 surface as a reliable CEI framework, in contrast, the prior decomposition of DENE additives will damage the CEI layer. As a result, the NCM83/graphite full cells with the LiPF6-EC/DEC-HTCN (BE-HTCN) electrolyte deliver a high capacity retention of 81.42% at 1 C after 300 cycles at a cutoff voltage of 4.5 V, whereas BE and BE-DENE electrolytes only deliver 64.01% and 60.05%. This nonsacrificial nitrile additive manipulation provides valuable guidance for developing aggressive high-capacity Ni-rich cathodes.

12.
Mod Pathol ; 35(2): 218-227, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34493824

RESUMO

Metastatic tumors (MTs) may show different characteristics of the immune microenvironment from primary tumors (PTs) in non-small cell lung cancer (NSCLC). The heterogeneity of immune markers in metastatic NSCLC and its associated factors has not been well demonstrated. In this study, 64 surgically resected specimens of paired PTs and MTs were obtained from 28 patients with NSCLC. Multiplex immunofluorescence (mIF; panel including programmed death-ligand 1 (PD-L1), Cytokeratin, CD8, and CD68) was performed on whole sections. The heterogeneity of the immune contexture of PD-L1 expression, infiltrating lymphocytes, and immune-to-tumor cell distances was quantified via digital image analysis. In a quantitative comparison of MTs and corresponding PTs, MTs showed higher PD-L1 expression levels, lower density of CD8+ cytotoxic T lymphocytes (CTLs), and longer spatial distance between CTLs and tumor cells. Subgroup analysis, which associated clinical factors, revealed that the heterogeneity of immune markers was more obvious in extrapulmonary, metachronous, and treated MTs, while fewer differences were observed in intrapulmonary, synchronous, and untreated MTs. In particular, MTs showed significantly higher PD-L1 expression and lower lymphocyte infiltration in metastatic NSCLC with EGFR mutations. Prognosis analysis showed that an increased density of CD8+ CTLs in MTs was associated with better overall survival (OS). Therefore, significant discrepancies in PD-L1 expression and lymphocyte infiltration in metastatic NSCLC are most likely associated with temporal heterogeneity with a history of anti-treatment and correlated with EGFR mutations. The detection of immune markers in re-obtained metastatic specimens may be required for immunotherapy prediction in these patients with metastatic NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/patologia , Linfócitos do Interstício Tumoral , Prognóstico , Microambiente Tumoral
13.
Mod Pathol ; 35(3): 403-411, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34518630

RESUMO

Standardized programmed death-ligand 1 (PD-L1) assessment in non-small cell lung cancer (NSCLC) is challenging, owing to inter-observer variability among pathologists and the use of different antibodies. There is a strong demand for the development of an artificial intelligence (AI) system to obtain high-precision scores of PD-L1 expression in clinical diagnostic scenarios. We developed an AI system using whole slide images (WSIs) of the 22c3 assay to automatically assess the tumor proportion score (TPS) of PD-L1 expression based on a deep learning (DL) model of tumor detection. Tests were performed to show the diagnostic ability of the AI system in the 22c3 assay to assist pathologists and the reliability of the application in the SP263 assay. A robust high-performance DL model for automated tumor detection was devised with an accuracy and specificity of 0.9326 and 0.9641, respectively, and a concrete TPS value was obtained after tumor cell segmentation. The TPS comparison test in the 22c3 assay showed strong consistency between the TPS calculated with the AI system and trained pathologists (R = 0.9429-0.9458). AI-assisted diagnosis test confirmed that the repeatability and efficiency of untrained pathologists could be improved using the AI system. The Ventana PD-L1 (SP263) assay showed high consistency in TPS calculations between the AI system and pathologists (R = 0.9787). In conclusion, a high-precision AI system is proposed for the automated TPS assessment of PD-L1 expression in the 22c3 and SP263 assays in NSCLC. Our study also indicates the benefits of using an AI-assisted system to improve diagnostic repeatability and efficiency for pathologists.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Inteligência Artificial , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/patologia , Reprodutibilidade dos Testes
14.
Appl Environ Microbiol ; 88(1): e0162221, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34669448

RESUMO

The multi-heme c-type cytochrome OmcS is one of the central components used for extracellular electron transport in the Geobacter sulfurreducens strain DL-1, but its role in other microbes, including other strains of G. sulfurreducens, is currently a matter of debate. Therefore, we investigated the function of OmcS in the G. sulfurreducens strain KN400, which is even more effective in extracellular electron transfer than the DL-1 strain. We found that deleting omcS from strain KN400 did not negatively impact the rate of Fe(III) oxide reduction and that the cells expressed conductive filaments. Replacing the wild-type pilin gene with the aro-5 pilin gene eliminated the OmcS-deficient strain's ability to transport electrons to insoluble electron acceptors and diminished filament conductivity. These results are consistent with the concept that electrically conductive pili are the primary conduit for long-range electron transfer in G. sulfurreducens and closely related species. These findings, coupled with the lack of OmcS homologs in other microbes capable of extracellular electron transfer, suggest that OmcS is not a common critical component for extracellular electron transfer. IMPORTANCE OmcS has been widely studied and noted to be one of the key components for extracellular electron exchange by the Geobacter sulfurreducens strain DL-1. However, the true importance of OmcS warrants further investigation because it is well known that few bacteria, even within the Geobacteraceae family, contain OmcS homologs, and many bacteria that are capable of extracellular electron transfer lack an abundance of any type of outer surface c-type cytochrome. In addition, there is debate about the importance of OmcS filaments in the mechanism of extracellular electron transport to insoluble electron acceptors by G. sulfurreducens. It has been suggested that filaments comprised of OmcS rather than e-pili are the predominant conductive filaments expressed by G. sulfurreducens. However, the results presented here, along with multiple other sources of evidence, indicate that OmcS filaments cannot be the primary, conductive, protein nanowires expressed by G. sulfurreducens.


Assuntos
Elétrons , Geobacter , Citocromos/metabolismo , Transporte de Elétrons , Compostos Férricos/metabolismo , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Geobacter/genética , Geobacter/metabolismo , Oxirredução
15.
Plant Cell ; 31(3): 663-686, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30538157

RESUMO

Plants develop tolerance to drought by activating genes with altered levels of epigenetic modifications. Specific transcription factors are involved in this activation, but the molecular connections within the regulatory system are unclear. Here, we analyzed genome-wide acetylated lysine residue 9 of histone H3 (H3K9ac) enrichment and examined its association with transcriptomes in Populus trichocarpa under drought stress. We revealed that abscisic acid-Responsive Element (ABRE) motifs in promoters of the drought-responsive genes PtrNAC006, PtrNAC007, and PtrNAC120 are involved in H3K9ac enhancement and activation of these genes. Overexpressing these PtrNAC genes in P trichocarpa resulted in strong drought-tolerance phenotypes. We showed that the ABRE binding protein PtrAREB1-2 binds to ABRE motifs associated with these PtrNAC genes and recruits the histone acetyltransferase unit ADA2b-GCN5, forming AREB1-ADA2b-GCN5 ternary protein complexes. Moreover, this recruitment enables GCN5-mediated histone acetylation to enhance H3K9ac and enrich RNA polymerase II specifically at these PtrNAC genes for the development of drought tolerance. CRISPR editing or RNA interference-mediated downregulation of any of the ternary members results in highly drought-sensitive P trichocarpa Thus, the combinatorial function of the ternary proteins establishes a coordinated histone acetylation and transcription factor-mediated gene activation for drought response and tolerance in Populus species.


Assuntos
Ácido Abscísico/metabolismo , Histonas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Populus/genética , Processamento de Proteína Pós-Traducional , Acetilação , Secas , Regulação da Expressão Gênica de Plantas , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Motivos de Nucleotídeos , Fenótipo , Proteínas de Plantas/genética , Populus/fisiologia , Regiões Promotoras Genéticas/genética , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional
16.
Environ Res ; 214(Pt 4): 114207, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36030910

RESUMO

Denitrifying anaerobic methane oxidation (DAMO) is a bioprocess utilizing methane as the electron source to remove nitrate or nitrite, but denitrification rate especially for nitrate-dependent DAMO is usually limited due to the low methane mass transfer efficiency. In this research, granular active carbon (GAC) was added to enhance the nitrate-dependent DAMO process. The results showed that the maximum nitrate removal rate of GAC assisted DAMO system reached as high as 61.17 mg L-1 d-1, 8 times higher than that of non-amended control SBR. The porous structure of GAC can not only adsorb methane, but also keep the internal DAMO archaea from being washed out, and thus benefits for DAMO archaea enrichment. The relative abundance of DAMO archaea accounted for 96.3% in GAC-SBR, which was significantly higher than that of non-amended control SBR system (29.9%). Furthermore, GAC amendment up-regulated metabolic status of denitrification and methane oxidation based on gene sequence composition. The absolute abundances of function genes (NC10 pmoA and ANME mcrA) in GAC-SBR were almost 20 times higher than that of non-amended control SBR. This study provides a novel technique to stimulate the nitrate-dependent DAMO process.


Assuntos
Metano , Nitratos , Anaerobiose , Reatores Biológicos , Carvão Vegetal , Desnitrificação , Nitritos , Óxidos de Nitrogênio , Oxirredução
17.
Biotechnol Appl Biochem ; 69(3): 951-962, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33878231

RESUMO

Tyrosinase is a key metalloenzyme for the biosynthesis of melanin that plays a critical role in the prevention of skin damage caused by ultraviolet (UV) radiation. However, the overproduction of melanin may cause a variety of skin diseases. Due to the toxicity and inefficiency of existing tyrosinase inhibitors, it is urgent to identify safe and potent alternatives from natural sources. Theaflavin, a single-component extracted from black tea, has been found to possess a variety of pharmacological activities. Herein, the inhibition kinetics of theaflavin on tyrosinase and inhibitory mechanism were determined using spectroscopy, molecular docking, and zebrafish model. The results showed that theaflavin inhibited the diphenolase activity of tyrosinase in a reversible mixed type manner with IC50 of 229.75 µmol/L and hindered the synthesis of melanin in zebrafish. This may be due to the formation of eight hydrogen bonds and hydrophobic effects between theaflavin and tyrosinase according to the results of molecular docking. To study the possible effects on the prevention of free radical-mediated skin cancer and photoaging caused by UV radiation, the antioxidation and UV filter properties of theaflavin were further verified. This study demonstrates that theaflavin is a potential multifunctional compound that can be used in cosmetic and medicinal products.


Assuntos
Antioxidantes , Monofenol Mono-Oxigenase , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Biflavonoides , Catequina , Inibidores Enzimáticos/farmacologia , Melaninas , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/química , Peixe-Zebra
18.
J Nanobiotechnology ; 20(1): 338, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858898

RESUMO

Despite explosive growth in the development of nano-drug delivery systems (NDDS) targeting tumors in the last few decades, clinical translation rates are low owing to the lack of efficient models for evaluating and predicting responses. Microfluidics-based tumor-on-a-chip (TOC) systems provide a promising approach to address these challenges. The integrated engineered platforms can recapitulate complex in vivo tumor features at a microscale level, such as the tumor microenvironment, three-dimensional tissue structure, and dynamic culture conditions, thus improving the correlation between results derived from preclinical and clinical trials in evaluating anticancer nanomedicines. The specific focus of this review is to describe recent advances in TOCs for the evaluation of nanomedicine, categorized into six sections based on the drug delivery process: circulation behavior after infusion, endothelial and matrix barriers, tumor uptake, therapeutic efficacy, safety, and resistance. We also discuss current issues and future directions for an end-use perspective of TOCs.


Assuntos
Sistemas de Liberação de Fármacos por Nanopartículas , Neoplasias , Humanos , Dispositivos Lab-On-A-Chip , Microfluídica , Nanomedicina , Neoplasias/tratamento farmacológico , Microambiente Tumoral
19.
Int J Mol Sci ; 23(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36077038

RESUMO

Due to easy storage and transportation, liquid hydrogen carriers will play a significant role in diversifying the energy supply pathways by transporting hydrogen on a large scale. Thus, in this study, amorphous carbonaceous materials have been employed for hydrogen production via ammonia decomposition under non-thermal plasma (NTP) conditions. The adsorption and splitting of ammonia over carbons differing in the chemical structure of surface functional groups have been investigated by in situ spectral studies directly under NTP conditions. As a result of NH3 physical and chemical sorption, surface species in the form of ammonium salts, amide and imide structures decompose immediately after switching on the plasma environment, and new functionalities are formed. Carbon catalysts are very active for NH3 splitting. The determined selectivity to H2 is close to 100% on N-doped carbon material. The data obtained indicate that the tested materials possess excellent catalytic ability for economical, COx-free hydrogen production from NH3 at a low temperature.


Assuntos
Amônia , Gases em Plasma , Amônia/química , Carbono/química , Catálise , Hidrogênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
20.
J Environ Manage ; 309: 114598, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35151137

RESUMO

The effectiveness of the adsorption process is determined by the type of adsorbent used, but some adsorbents require a significant amount of processing to achieve the desired quality, and this has become a drawback economically and environmentally. This study focused on mitigating the issue of waste management and land pollution by using amarula waste biomass, which is a low-cost adsorbent that is obtained from the industrial waste by-product. The amarula shell (AmSh) waste was found to have a higher adsorption efficiency of 30 ± 3% compared to the amarula seed (AmSe) waste and the amarula fruit (AmWa) waste, which had 19 ± 5% and 9.5 ± 0.7% efficiency, respectively. It was found that the amarula waste biomass performed better at lower adsorption temperatures. The adsorption capacity was found to decrease with an increase in the quantity of the biomass. Kinetic models were applied to the experimental data. Thermodynamic parameters were also studied to determine the spontaneity of the adsorption process. The characteristics of both the fresh and used amarula waste biomass was analyzed by using Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy with Energy Dispersive Spectroscopy (FESEM-EDS), Brunauer-Emmett-Teller (BET) and Thermogravimetric Analysis (TGA). It was then concluded that cellulose and hemicellulose structures in amarula waste biomass played a major role in reducing the content of dibenzothiophene in model diesel fuel.


Assuntos
Gasolina , Poluentes Químicos da Água , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Tiofenos , Poluentes Químicos da Água/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA