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1.
Ecotoxicol Environ Saf ; 273: 116151, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38412633

RESUMO

This research aimed to develop a new method for clean utilization and treatment of landfill leachate and solid waste weathered coal. Landfill leachate and weathered coal were adopted for combined anaerobic fermentation for methane production. The characteristics of microbial community, mechanism of biological methane production, and utilization characteristics of fermentation broth and solid residue for co-fermentation were analyzed through metagenomics, soluble organic matter detection and thermogravimetric (TG) analysis. The obtained results revealed that combined anaerobic fermentation increased methane production by 80.1%. Syntrophomonas, Salipiger, Methanosaeta and Methanothrix were highly correlated. Gene abundances of 2-oxoacid ferredoxin oxidoreductase and enolase were increased in methane conversion pathway mainly by acetic acid. Pyruvate-ferroredoxin oxidoreductase, 2-oxoglutarate synthase and succinate dehydrogenase acetate synthase intensified electron transfer pathways among microorganisms. Fulvic acid, tyrosine and tryptophan contents were high in fermentation broth. Volatile decomposition temperature, ignition point and residual char combustion temperature of residual coal were decreased and combustion was more stable. The obtained results showed that the co-fermentation of landfill leachate and weathered coal improved biological methane gas production, degraded weathered coal and improved combustion performance, which provided a new idea for weathered coal clean utilization.


Assuntos
Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Fermentação , Anaerobiose , Metano/metabolismo , Oxirredutases/metabolismo , Reatores Biológicos
2.
Bioprocess Biosyst Eng ; 47(4): 483-493, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38478120

RESUMO

To improve the methanogenic efficiency of lignite anaerobic fermentation and explore innovative approaches to sludge utilization, a co-fermentation technique involving lignite and sludge was employed for converting biomass into biomethane. Volatile suspended solids were introduced as a native enrichment of the sludge and mixed with lignite for fermentation. The synergistic fermentation mechanism between sludge and lignite for biomethane production was analyzed through biochemical methane potential experiments, measurement of various parameters pre- and post-fermentation, observation of bacterial population changes during the peak of reaction, carbon migration assessment, and evaluation of rheological characteristics. The results showed that the addition of sludge in the anaerobic fermentation process improved the microorganisms' ability to degrade lignite and bolstered biomethane production. Notably, the maximum methane production recorded was 215.52 mL/g-volatile suspended solids, achieved at a sludge to coal ratio of 3:1, with a synergistic growth rate of 25.37%. Furthermore, the removal rates of total suspended solids, and total chemical oxygen demand exhibited an upward trend with an increasing percentage of sludge in the mixture. The relative abundance and activity of the methanogens population were found to increase with an appropriate ratio of sludge to lignite. This observation confirmed the migration of carbon between the solid-liquid-gas phases, promoting enhanced system affinity. Additionally, the changes in solid-liquid phase parameters before and after the reaction indicated that the addition of sludge improved the system's degradation capacity. The results of the study hold significant implications in realizing the resource utilization of sludge and lignite while contributing to environmental protection endeavors.


Assuntos
Carvão Mineral , Esgotos , Fermentação , Esgotos/microbiologia , Metano/metabolismo , Carbono , Anaerobiose , Reatores Biológicos
3.
Environ Res ; 227: 115777, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36966989

RESUMO

The present study aims at using lipid in a novel way to improve the efficiency of methane production from lignite anaerobic digestion. The obtained results showed an increase by 3.13 times of the cumulative biomethane content of lignite anaerobic fermentation, when 1.8 g lipid was added. The gene expression of functional metabolic enzymes was also found to be enhanced during the anaerobic fermentation. Moreover, the enzymes related to fatty acid degradation such as long-chain Acyl-CoA synthetase and Acyl-CoA dehydrogenase were increased by 1.72 and 10.48 times, respectively, which consequently, accelerated the conversion of fatty acid. Furthermore, the addition of lipid enhanced the carbon dioxide trophic and acetic acid trophic metabolic pathways. Hence, the addition of lipids was argued to promote the production of methane from lignite anaerobic fermentation, which provided a new insight for the conversion and utilization of lipid waste.


Assuntos
Ácidos Graxos , Metano , Fermentação , Anaerobiose , Ácidos Graxos/metabolismo , Catálise , Reatores Biológicos
4.
J Environ Manage ; 343: 118058, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37229851

RESUMO

Metagenomic sequencing technology was applied to evaluate differences in the anaerobic fermentation process of coal slimes by analyzing microbial diversity, functional activity structure, and cooperative relationship during the anaerobic fermentation of coal slimes with different coal ranks. The obtained results showed that the production of biomethane from coal slime was decreased by increasing metamorphism degree. Internal reason was higher abundance of microbial community in low rank coal slimes compared to that in high rank coal which had higher activity in the gene expression of key steps such as hydrolysis and acidification, methanation and the production of hydrogen and acetic acid. Acetic acid decarboxylation and CO2 reduction are two key pathways of methanation process. At the same time, K11261 (formylmethanofuran dehydrogenase subunit) and K01499 (methenyltetrahydromethanopterin cyclohydrolase) genes were further enriched in low rank slime systems, which enhanced the proportion of CO2 reduction in methanation pathway and was beneficial to biomethane production. Research revealed the roles of different coal slime ranks in biomethane production process and is considered as an important reference significance for further exploration of coal slime resource utilization.


Assuntos
Carvão Mineral , Metagenômica , Fermentação , Dióxido de Carbono , Metano , Anaerobiose , Acetatos , Reatores Biológicos
5.
Perfusion ; 35(8): 806-813, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32419612

RESUMO

BACKGROUND: Catheter-related thrombosis may lead to catheter infections and failure, further deep venous thrombosis, and pulmonary embolism. Recognizing the risk factors for catheter-related thrombosis is extremely important to inform the development of catheter care guidelines. METHODS: Data were collected from a total of 1,532 patients who had undergone venous catheterization, including indwelling catheterization from 19 March 2019 to 30 March 2019 in the Sun Yat-sen Memorial Hospital. The factors for which data were to be collected included the patients' physical characteristics, catheter-related factors, and catheter care-related factors. Logistic regression analysis, the chi-squared test, Fisher's exact test, and the t-test were used to analyze the data. RESULTS: Of the 1,532 patients studied, 28 developed intraductal thrombi, and of the factors analyzed, malignancy, a catheterization history, a history of thrombophilia, surgery during the week before catheterization, the catheterization duration, and anticoagulant therapy were significant risk factors associated with catheter-related thrombosis (all p < 0.05). There were no significant associations between the catheter brand, the number of lumens, the insertion direction, or the factors associated with catheter care and catheter-related thrombosis (all p > 0.05). CONCLUSION: Our study incorporated clear and systematic risk factors associated with catheter-related thrombosis. Malignancy, history of thrombophilia, history of catheterization, surgery during the week before catheterization, and catheterization duration were associated with increased risks of catheter-related thrombosis. Prophylactic anticoagulation was effective for preventing and treating catheter-related thrombosis.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Trombose/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cateterismo Venoso Central/métodos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
6.
J Cell Biochem ; 120(6): 9400-9408, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30536812

RESUMO

Peripheral inflammation in male C57BL/6 mice was induced by intraplantar injection of 20 µL complete freund's adjuvant (CFA) in the left hind paw. Mice were randomly divided into three groups: Sham, CFA, and propofol+CFA. Mechanical allodynia was assessed by von Frey analysis, and heat hyperalgesia was detected by exposure of the plantar surface to a beam of radiant heat. Propofol significantly attenuated the severity and duration of CFA-induced pain hypersensitivity, heat hyperalgesia, and paw edema. Propofol inhibited CFA-induced microglia activation, and markedly decreased CFA-induced ionized calcium binding adapter molecule 1 (IBA-1) expression. Propofol inhibited CFA-induced expression of p-extracellular signal-regulated kinase1/2 (p-ERK1/2) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65, as demonstrated by Western blot analysis. In addition, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assays indicated that propofol had no cytotoxic effect on BV2 microglia cells. Reverse transcription-quantitative-polymerase chain reaction and enzyme-linked immunosorbent assay results demonstrated that propofol attenuates CFA-induced tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1ß production in the spinal cord as well as in BV2 cells. Taken together, these results demonstrate that propofol attenuates CFA-induced neuroinflammation (TNF-α, IL-6, and IL-1ß expression) through a mechanism that involves activation of ERK1/2/NF-κB signaling pathway.


Assuntos
Inflamação/tratamento farmacológico , Microglia/efeitos dos fármacos , Dor/tratamento farmacológico , Propofol/farmacologia , Animais , Modelos Animais de Doenças , Adjuvante de Freund/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Interleucina-1beta/genética , Interleucina-6/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Microglia/patologia , Dor/genética , Dor/patologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Fator de Transcrição RelA/genética , Fator de Necrose Tumoral alfa/genética
7.
World J Surg Oncol ; 17(1): 175, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31672162

RESUMO

BACKGROUND AND OBJECTIVES: Lymph node metastasis is a key factor in predicting and determining the prognosis of patients with colorectal cancer (CRC). Sodium channels are highly expressed in a variety of tumors and are closely related to tumor development, metastasis, and invasion. We investigated the relationship between the expressions of different subtypes of Nav channels and lymph node metastasis of CRC. METHODS: Real-time PCR (RT-qPCR) was carried out to measure the expressions of different sodium channel subtypes, chemokine receptors (CCR2, CCR4, CCR7), and lymphocyte infiltration-related biomarkers (CD3e, CD8a, IL-2RA) in CRC tissues from 97 patients. The expressions of Nav1.5 and Nav1.6 in surgically isolated lymph nodes were detected by immunohistochemistry. Correlation analysis between expressions of different genes and lymph node metastasis was performed by two-tailed t test. RESULTS: Nav1.1 and Nav1.6 were highly expressed in CRC tissues and positively correlated with CRC lymph node metastasis. Nav1.6 was also highly expressed in metastatic lymph nodes. Further analysis showed that the high expression of Nav1.6 was closely related to the one of CCR2\CCR4 in tumor lymph node metastasis. CONCLUSIONS: These results suggested that Nav1.6 might be a novel marker for CRC lymph node metastasis.


Assuntos
Neoplasias Colorretais/patologia , Canal de Sódio Disparado por Voltagem NAV1.6/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/metabolismo , Feminino , Humanos , Metástase Linfática , Linfócitos do Interstício Tumoral/patologia , Masculino , Pessoa de Meia-Idade , Receptores CCR2/análise , Receptores CCR4/análise
8.
Nano Lett ; 18(9): 6017-6021, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30084642

RESUMO

Functional fabrics with various unique properties are necessary for making fantastic superior costumes just like a superhero suit in Marvel Comics, which are not only dreams of boys but also emerging textiles to facilitate human life. On the basis of the inspiration of a phenomenon in an extracurricular experiment for kids, we develop a biofabrication strategy to endow silk textiles with various unique physical and chemical properties of functional nanomaterials, where the functional textiles are weaved using silk spun by silkworms that are fed with functional nanomaterials. To confirm the feasibility of this strategy, a photoluminescent plain weave was prepared successfully via feeding biocompatible luminescent nanoparticles to Bombyx mori silkworms. As the functional nanomaterials are enclosed in the silkfibers, the given special properties will be permanent for further application. Considering the wondrous diversity of properties that a variety of nanomaterials possesses may be given to silk fabric, it is promising to see various miraculous costumes in the coming future.

9.
Sensors (Basel) ; 18(9)2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30205472

RESUMO

Recently, the concept of the difference and sum co-array (DSCa) has attracted much attention in array signal processing due to its high degree of freedom (DOF). In this paper, the DSCa of the nested array (NA) is analyzed and then an improved nested configuration known as the diff-sum nested array (DsNA) is proposed. We find and prove that the sum set for the NA contains all the elements in the difference set. Thus, there exists the dual characteristic between the two sets, i.e., for the difference result between any two sensor locations of the NA, one equivalent non-negative/non-positive sum result of two other sensor locations can always be found. In order to reduce the redundancy for further DOF enhancement, we develop a new DsNA configuration by moving nearly half the dense sensors of the NA to the right side of the sparse uniform linear array (ULA) part. These moved sensors together with the original sparse ULA form an extended sparse ULA. For analysis, we provide the closed form expressions of the DsNA locations as well as the DOF. Compared with some novel sparse arrays with large aperture such as the NA, coprime array and augmented nested array, the DsNA can achieve a higher number of DOF. The effectiveness of the proposed array is proved by the simulations.

10.
Sensors (Basel) ; 18(2)2018 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-29370138

RESUMO

In this paper, we propose a vectorized noncircular MUSIC (VNCM) algorithm based on the concept of the coarray, which can construct the difference and sum (diff-sum) coarray, for direction finding of the noncircular (NC) quasi-stationary sources. Utilizing both the NC property and the concept of the Khatri-Rao product, the proposed method can be applied to not only the ULA but also sparse arrays. In addition, we utilize the quasi-stationary characteristic instead of the spatial smoothing method to solve the coherent issue generated by the Khatri-Rao product operation so that the available degree of freedom (DOF) of the constructed virtual array will not be reduced by half. Compared with the traditional NC virtual array obtained in the NC MUSIC method, the diff-sum coarray achieves a higher number of DOFs as it comprises both the difference set and the sum set. Due to the complementarity between the difference set and the sum set for the coprime array, we choose the coprime array with multiperiod subarrays (CAMpS) as the array model and summarize the properties of the corresponding diff-sum coarray. Furthermore, we develop a diff-sum coprime array with multiperiod subarrays (DsCAMpS) whose diff-sum coarray has a higher DOF. Simulation results validate the effectiveness of the proposed method and the high DOF of the diff-sum coarray.

11.
Cell Physiol Biochem ; 38(6): 2389-400, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27299310

RESUMO

BACKGROUND/AIMS: Long non-coding RNAs (lncRNAs) play an important role in tumorigenesis. However, the role of lncRNA expression in human Non-small cell lung cancer (NSCLC) biology, prognosis and molecular classification remains unknown. METHODS: We established the IncRNA profile in NSCLC by re-annotation of microarrays from the Gene expression omnibus database. Quantitative real-time PCR was used to determine expression of LINC00342. RESULTS: 6066 differentially expressed IncRNAs were identified and we found a novel IncRNA, LINC00342 was significantly up-regulated in NSCLC tissues compared with normal tissues. We confirmed the over-expression of LINC00342 in a cohort of NSCLC patients and found LINC00342 expression level was positively correlated with lymph node metastasis and TNM stages. Furthermore, in a large online database of 1942 NSCLC patients, high expression of LINC00342 indicated poor Overall survival (HR = 1.28, 95% CI: 1.13-1.45) and post progression survival (HR = 1.43, 95% CI: 1.09-1.88). Bioinformatics analyses showed that LINC00342 was co-expressed with different protein-coding genes in NSCLC and normal tissues. Additionally, gene set enrichment analyses found that PTEN and P53 pathways genes were enriched in the groups with higher LINC00342 expression level. By small interfering RNAs mediated silence of LINC00342, proliferation ability was significantly inhibited in lung cancer cell line. CONCLUSION: To summary, our findings indicate that a set of IncRNAs are differentially expressed in NSCLC and we characterized a novel IncRNA, LINC00342 which is significantly up-regulated in NSCLC and could be a prognostic biomarker.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Linhagem Celular Tumoral , Feminino , Humanos , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Transcriptoma
12.
Tumour Biol ; 35(1): 463-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23959471

RESUMO

The Hippo pathway plays a major role in development and organ size control, and its dysregulation contributes to tumorigenesis. WWTR1 is a transcription coactivator acting downstream of the Hippo pathway. Recently, WWTR1 has been reported to be overexpressed in several human cancers including lung cancer. However, the molecular mechanism of WWTR1 regulating lung cancer aggressiveness remains ambiguous. In the present study, we analyzed the expression of WWTR1 in NSCLC cell lines and found that WWTR1 was overexpressed at both the mRNA and protein levels. Knockdown of WWTR1 by siRNA interference in A549 cells significantly inhibited cell proliferation and increased paclitaxel-induced apoptosis. On the other side, WWTR1 overexpression in HBE cell line promoted cell proliferation and inhibited apoptosis. In addition, we found that the decreased proliferation after siRNA treatment was due to cell cycle arrest. Further analysis showed that WWTR1 could induce cyclin A, connective tissue growth factor (CTGF) expression, and inhibit caspase3 cleavage. In conclusion, WWTR1 promotes malignant cell growth and inhibits apoptosis by cyclin A and CTGF regulation.


Assuntos
Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Fator de Crescimento do Tecido Conjuntivo/genética , Ciclina A/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Caspase 3/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Ciclina A/metabolismo , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Interferência de RNA , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional
13.
Tumour Biol ; 35(6): 5389-93, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24519065

RESUMO

Lung cancer is one of the most spread cancers in the world. The X-ray repair cross-complementing group 1 (XRCC1) gene plays an important role in the development of lung cancer. The objective of this study is to investigate the potential association of XRCC1 genetic polymorphisms with the susceptibility to lung cancer. In totally, 361 lung cancer patients (male, 276; female, 85; mean age, 62.55) and 361 cancer-free controls (male, 253; female, 108; mean age, 61.33) were enrolled in this case-control study. The genotypes of XRCC1 c.1471G>A genetic polymorphism were determined by the created restriction site-polymerase chain reaction (CRS-PCR) and DNA sequencing methods. The influence of XRCC1 gene on the susceptibility to lung cancer was analyzed by the analyses association. Our data indicated that significant differences were found in the frequencies of allelic and genotypic between lung cancer patients and cancer-free controls. The c.1471G>A genetic polymorphism was statistically associated with increased susceptibility to lung cancer [AA vs. GG: odds ratio (OR)=2.75, 95 % confidence interval (CI) = 1.55-4.88, P<0.001; AA vs. GA/GG: OR=2.69, 95 % CI=1.55-4.69, P<0.001; A vs. G: OR=1.37, 95 % CI=1.09-1.71, P=0.007]. The allele A and genotype AA may contribute to the susceptibility to lung cancer. Taken together, these results showed that the functional c.1471G>A genetic polymorphism of XRCC1 was associated with lung cancer susceptibility in the studied population.


Assuntos
Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença , Neoplasias Pulmonares/genética , Polimorfismo Genético , Adulto , Idoso , Estudos de Casos e Controles , China/etnologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
14.
Methods Enzymol ; 696: 231-247, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38658081

RESUMO

Nonheme iron enzymes stand out as one of the most versatile biocatalysts for molecular functionalization. They facilitate a wide array of chemical transformations within biological processes, including hydroxylation, chlorination, epimerization, desaturation, cyclization, and more. Beyond their native biological functions, these enzymes possess substantial potential as powerful biocatalytic platforms for achieving abiological metal-catalyzed reactions, owing to their functional and structural diversity and high evolvability. To this end, our group has recently engineered a series of nonheme iron enzymes to employ non-natural radical-relay mechanisms for abiological radical transformations not previously known in biology. Notably, we have demonstrated that a nonheme iron enzyme, (S)-2-hydroxypropylphosphonate epoxidase from Streptomyces viridochromogenes (SvHppE), can be repurposed into an efficient and selective biocatalyst for radical fluorine transfer reactions. This marks the first known instance of a redox enzymatic process for C(sp3)F bond formation. This chapter outlines the detailed experimental protocol for engineering SvHPPE for fluorination reactions. Furthermore, the provided protocol could serve as a general guideline that might facilitate other engineering endeavors targeting nonheme iron enzymes for novel catalytic functions.


Assuntos
Biocatálise , Flúor , Halogenação , Engenharia de Proteínas , Streptomyces , Flúor/química , Engenharia de Proteínas/métodos , Streptomyces/enzimologia , Streptomyces/genética , Oxirredutases/metabolismo , Oxirredutases/genética , Oxirredutases/química , Oxirredução , Ferroproteínas não Heme/química , Ferroproteínas não Heme/metabolismo , Ferroproteínas não Heme/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química
15.
Sci Total Environ ; 946: 174085, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38908596

RESUMO

Coalbed methane (CBM) presents a promising energy source for addressing global energy shortages. Nonetheless, challenges such as low gas production from individual wells and difficulties in breaking gels at low temperatures during extraction hinder its efficient utilization. Addressing this, we explored native microorganisms within coal seams to degrade guar gum, thereby enhancing CBM production. However, the underlying mechanisms of biogenic methane production by synergistic biodegradation of lignite and guar gum remain unclear. Research results showed that the combined effect of lignite and guar gum enhanced the production, yield rate and concentration of biomethane. When the added guar gum content was 0.8 % (w/w), methane production of lignite and guar gum reached its maximum at 561.9 mL, which was 11.8 times that of single lignite (47.3 mL). Additionally, guar gum addition provided aromatic and tryptophan proteins and promoted the effective utilization of CC/CH and OCO groups on the coal surface. Moreover, the cooperation of lignite and guar gum accelerated the transformation of volatile fatty acids into methane and mitigated volatile fatty acid inhibition. Dominant bacteria such as Sphaerochaeta, Macellibacteroides and Petrimonas improved the efficiency of hydrolysis and acidification. Electroactive microorganisms such as Sphaerochaeta and Methanobacterium have been selectively enriched, enabling the establishment of direct interspecies electron transfer pathways. This study offers valuable insights for increasing the production of biogenic CBM and advancing the engineering application of microbial degradation of guar gum fracturing fluid. Future research will focus on exploring the methanogenic capabilities of lignite and guar gum in in-situ environments, as well as elucidating the specific metabolic pathways involved in their co-degradation.


Assuntos
Biodegradação Ambiental , Carvão Mineral , Galactanos , Mananas , Metano , Gomas Vegetais , Gomas Vegetais/metabolismo , Mananas/metabolismo , Galactanos/metabolismo , Metano/metabolismo
16.
Nat Synth ; 3(8): 958-966, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39364063

RESUMO

In recent years there has been a surge in the development of methods for the synthesis of organofluorine compounds. However, enzymatic methods for C-F bond formation have been limited to nucleophilic fluoride substitution. Here, we report the incorporation of iron-catalysed radical fluorine transfer, a reaction mechanism that is not used in naturally occurring enzymes, into enzymatic catalysis for the development of biocatalytic enantioselective C(sp 3)-F bond formation. Using this strategy, we repurposed (S)-2-hydroxypropylphosphonate epoxidase from Streptomyces viridochromogenes (SvHppE) to catalyse an N-fluoroamide directed C(sp 3)-H fluorination. Directed evolution has enabled SvHppE to be optimized, forming diverse chiral benzylic fluoride products with turnover numbers of up to 180 and with excellent enantiocontrol (up to 94% e.e.). Mechanistic investigations showed that the N-F bond activation is the rate-determining step, and the strong preference for fluorination in the presence of excess NaN3 can be attributed to the spatial proximity of the carbon-centered radical to the iron-bound fluoride.

17.
Neuro Oncol ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093629

RESUMO

BACKGROUND: Advances in our understanding of the molecular biology of meningiomas have led to significant gains in the ability to predict patient prognosis and tumor recurrence and to identify novel targets for therapeutic design. Specifically, classification of meningiomas based on DNA methylation has greatly improved our ability to risk stratify patients, however new questions have arisen in terms of the underlying impact these DNA methylation signatures have on meningioma biology. METHODS: This study utilizes RNA-seq data from 486 meningioma samples corresponding to three meningioma DNA methylation groups (Merlin-intact, Immune-enriched, and Hypermitotic), followed by in vitro experiments utilizing human meningioma cell lines. RESULTS: We identify alterations in RNA splicing between meningioma DNA methylation groups including individual splicing events that correlate with Hypermitotic meningiomas and predict tumor recurrence and overall patient prognosis and compile a set of splicing events that can accurately predict DNA methylation classification based on RNA-seq data. Furthermore, we validate these events using RT-PCR in patient samples and meningioma cell lines. Additionally, we identify alterations in RNA binding proteins and splicing factors that lie upstream of RNA splicing events, including upregulation of SRSF1 in Hypermitotic meningiomas which we show drives alternative RNA splicing changes. Finally, we design splice switching antisense oligonucleotides to target RNA splicing changes in NASP and MFF observed in Hypermitotic meningiomas, providing a rationale for RNA-based therapeutic design. CONCLUSIONS: RNA splicing is an important driver of meningioma phenotypes that can be useful in prognosticating patients and as a potential exploit for therapeutic vulnerabilities.

18.
Nat Commun ; 15(1): 7873, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251601

RESUMO

Meningiomas are associated with inactivation of NF2/Merlin, but approximately one-third of meningiomas with favorable clinical outcomes retain Merlin expression. Biochemical mechanisms underlying Merlin-intact meningioma growth are incompletely understood, and non-invasive biomarkers that may be used to guide treatment de-escalation or imaging surveillance are lacking. Here, we use single-cell RNA sequencing, proximity-labeling proteomic mass spectrometry, mechanistic and functional approaches, and magnetic resonance imaging (MRI) across meningioma xenografts and patients to define biochemical mechanisms and an imaging biomarker that underlie Merlin-intact meningiomas. We find Merlin serine 13 (S13) dephosphorylation drives meningioma Wnt signaling and tumor growth by attenuating inhibitory interactions with ß-catenin and activating the Wnt pathway. MRI analyses show Merlin-intact meningiomas with S13 phosphorylation and favorable clinical outcomes are associated with high apparent diffusion coefficient (ADC). These results define mechanisms underlying a potential imaging biomarker that could be used to guide treatment de-escalation or imaging surveillance for patients with Merlin-intact meningiomas.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias Meníngeas , Meningioma , Neurofibromina 2 , Via de Sinalização Wnt , Meningioma/diagnóstico por imagem , Meningioma/metabolismo , Meningioma/patologia , Meningioma/genética , Humanos , Fosforilação , Neurofibromina 2/metabolismo , Neurofibromina 2/genética , Animais , Imageamento por Ressonância Magnética/métodos , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/metabolismo , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/genética , Camundongos , Linhagem Celular Tumoral , beta Catenina/metabolismo , beta Catenina/genética , Feminino , Serina/metabolismo , Masculino , Proteômica/métodos , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética
19.
BMC Microbiol ; 13: 304, 2013 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-24373636

RESUMO

BACKGROUND: For a long time, Enterococcus faecium was considered a harmless commensal of the mammalian gastrointestinal (GI) tract and was used as a probiotic in fermented foods. In recent decades, E. faecium has been recognised as an opportunistic pathogen that causes diseases such as neonatal meningitis, urinary tract infections, bacteremia, bacterial endocarditis and diverticulitis. E. faecium could be taken into space with astronauts and exposed to the space environment. Thus, it is necessary to observe the phenotypic and molecular changes of E. faecium after spaceflight. RESULTS: An E. faecium mutant with biochemical features that are different from those of the wild-type strain was obtained from subculture after flight on the SHENZHOU-8 spacecraft. To understand the underlying mechanism causing these changes, the whole genomes of both the mutant and the WT strains were sequenced using Illumina technology. The genomic comparison revealed that dprA, a recombination-mediator gene, and arpU, a gene associated with cell wall growth, were mutated. Comparative transcriptomic and proteomic analyses showed that differentially expressed genes or proteins were involved with replication, recombination, repair, cell wall biogenesis, glycometabolism, lipid metabolism, amino acid metabolism, predicted general function and energy production/conversion. CONCLUSION: This study analysed the comprehensive genomic, transcriptomic and proteomic changes of an E. faecium mutant from subcultures that were loaded on the SHENZHOU-8 spacecraft. The implications of these gene mutations and expression changes and their underlying mechanisms should be investigated in the future. We hope that the current exploration of multiple "-omics" analyses of this E. faecium mutant will provide clues for future studies on this opportunistic pathogen.


Assuntos
Proteínas de Bactérias/análise , Enterococcus faecium/química , Enterococcus faecium/genética , Expressão Gênica , Mutação , RNA Mensageiro/análise , Voo Espacial , Análise Mutacional de DNA , Enterococcus faecium/isolamento & purificação , Genes Bacterianos , Genoma Bacteriano , Humanos , Dados de Sequência Molecular , RNA Mensageiro/genética , Análise de Sequência de DNA , Ausência de Peso
20.
Front Microbiol ; 14: 1114201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846781

RESUMO

Coalbed water is a semi-open system connecting underground coalbeds with the external environment. Microorganisms in coalbed water play an important role in coal biogasification and the carbon cycle. The community assemblages of microorganisms in such a dynamic system are not well understood. Here, we used high-throughput sequencing and metagenomic analysis to investigate microbial community structure and identify the potential functional microorganisms involved in methane metabolism in coalbed water in the Erlian Basin, a preferred low-rank coal bed methane (CBM) exploration and research area in China. The results showed that there were differences in the responses of bacteria and archaea to seasonal variation. Bacterial community structure was affected by seasonal variation but archaea was not. Methane oxidation metabolism dominated by Methylomonas and methanogenesis metabolism dominated by Methanobacterium may exist simultaneously in coalbed water.

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