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Novel microbial strains capable of efficient degradation of TNT and typical intermediates (2-ADNT and 4-ADNT) in aerobic/anaerobic environment were screened and isolated from ammunition-contaminated sites. The key genomes, transcriptomes, proteins, and metabolic factors for microbial detoxification/tolerance to pollutants in anaerobic and aerobic environments were analyzed for the first time. The bacterial genome, which is rich in metabolism and environmental information-processing functional genes, provides transcriptional and translational-related proteins for detoxifying/tolerating pollutants. At the transcriptional level, bacteria significantly expressed genes related to inositol phosphate metabolism for regulating membrane transport, maintaining the cytoskeleton, and signal transduction. At the protein level, genes involved in antioxidation, fat metabolism, sugar synthesis/degradation, and pyruvate metabolism were significantly expressed. At the metabolic level, riboflavin metabolism, which regulates membrane integrity, protects against oxidative stress, and maintains the sugar-protein-fat balance, showed significant responses. Bacteria simultaneously regulate amino acid metabolism, carbohydrate metabolism, and N/P/S cycles to maintain homeostatic cellular energy supplies. The key pathway for pollutant degradation in bacteria is nitrotoluene degradation. The molecular mechanism of bacterial tolerance to pollutants involves the regulation of oxidative phosphorylation and basic cycle pathways to maintain gene transcription, protein translation, and metabolic cycles.
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Seas worldwide are threatened by an emerging source of pollution as millions of tons of warfare materials were dumped after the World Wars. As their metal shells are progressively corroding, energetic compounds (EC) leak out and distribute in the marine environment. EC are taken up by aquatic organisms and pose a threat to both the marine ecosphere and the human seafood consumer because of their toxicity and potential carcinogenicity. Here, sediment samples and fish from different locations in the German North Sea of Lower Saxony were examined to determine whether EC transfer to fish living close to munition dumping areas. EC were found in sediments with a maximum concentration of 1.5 ng/kg. All analyzed fish muscle tissues/fillets and bile samples were positive for EC detection. In bile, the max. EC concentrations ranged between 0.25 and 1.25 ng/mL. Interestingly, while detected TNT metabolites in the muscle tissues were in concentrations of max. 1 ng/g (dry weight), TNT itself was found in concentrations of up to 4 ng/g (dry weight). As we found considerable higher amounts of non-metabolized TNT in the fish muscle, rather than TNT metabolites, we conclude an additional absorption route of EC into fish other than per diet. This is the first study to detect EC in the edible parts of fish caught randomly in the North Sea.
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Metal and metal oxide nanoparticles are gaining immense attention among researchers owing to their admirable application potentials in various therapeutic events. Titanium dioxide (TiO2) has been recognized as one of the leading candidates in this category and holds wide interest within the scientific community. Among the various morphological nanoforms of TiO2, nanotube is grabbing remarkable attention as they have succeeded as an active vehicle in various medical procedures like intravascular stenting, drug delivery, as biosensors etc. This ultimately demands toxicity profiling of nanotubes in various aspects. Present study elaborates a concept through which acute toxicity profiling of TiO2 nanotubes in adult Wistar rats is presented. TNTs were synthesized via solvo-thermal approach and surface coated with a biocompatible polymer; Pluronic-F127 (P-F127). This step assists in ameliorating the troubles associated with the nanomaterial dispersion stability. The experimental rats were intraperitoneally administered with TNT-P (10â¯mg/kg) and sacrificed on different time periods (3rd, 7th and 14th days). Biodistribution of the material was tracked in major tissues including brain, liver, spleen and kidneys. A set of acute toxicity studies was performed which comprises hematology evaluation, biochemical studies, antioxidant detection, analysis of urine parameters, immune modulation study and histopathology evaluation. Many of the experiments revealed an unaltered physiological response in rats; except for some biochemical and hematology parameters. Overall study suggests that, TNT-P do not result into a negative response in Wistar rats over 14 days.
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Nanotubos , Poloxâmero , Ratos Wistar , Titânio , Animais , Titânio/química , Poloxâmero/química , Nanotubos/química , Ratos , Distribuição Tecidual , Masculino , Testes de Toxicidade AgudaRESUMO
An external electric field is an effective tool to induce the polymorphic transformation of molecular crystals, which is important practically in the chemical, material, and energy storage industries. However, the understanding of this mechanism is poor at the molecular level. In this work, two types of order parameters (OPs) were constructed for the molecular crystal based on the intermolecular distance, bond orientation, and molecular orientation. Using the K-means clustering algorithm for the sampling of OPs based on the Euclidean distance and density weight, the polymorphic transformation of TNT was investigated using a finite temperature string (FTS) under external electric fields. The potential of mean force (PMF) was obtained, and the essence of the polymorphic transformation between o-TNT and m-TNT was revealed, which verified the effectiveness of the FTS method based on K-means clustering to OPs. The differences in PMFs between the o-TNT and transition state were decreased under external electric fields in comparison with those in no field. The fields parallel to the c-axis obviously affected the difference in PMF, and the relationship between the changes in PMFs and field strengths was found. Although the external electric field did not promote the convergence, the time of the polymorphic transformation was reduced under the external electric field in comparison to its absence. Moreover, under the external electric field, the polymorphic transformation from o-TNT to m-TNT occurred while that from m-TNT to o-TNT was prevented, which was explained by the dipole moment of molecule, relative permittivity, chemical potential difference, nucleation work and nucleation rate. This confirmed that the polymorphic transformation orientation of the molecular crystal could be controlled by the external electric field. This work provides an effective way to explore the polymorphic transformation of the molecular crystals at a molecular level, and it is useful to control the production process and improve the performance of energetic materials by using the external electric fields.
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Dinitrotoluene sulfonates (DNTSes) are highly toxic hazards regulated by the Resource Conservation and Recovery Act (RCRA) in the United States. The trinitrotoluene (TNT) red water formed during the TNT purification process consists mainly of DNTSes. Certain plants, including switchgrass, reed and alfalfa, can detoxify low concentrations of DNTS in TNT red water-contaminated soils. However, the precise mechanism by which these plants detoxify DNTS remains unknown. In order to aid in the development of phytoremediation resources with high DNTS removal rates, we identified and characterized 1-hydroxymethyl-2,4-dinitrobenzene sulfonic acid (HMDNBS) and its glycosylated product HMDNBS O-glucoside as the degradation products of 2,4-DNT-3-SO3Na, the major isoform of DNTS in TNT red water-contaminated soils, in switchgrass via LC-MS/MS- and NMR-based metabolite analyses. Transcriptomic analysis revealed that 15 UDP-glycosyltransferase genes were dramatically upregulated in switchgrass plants following 2,4-DNT-3-SO3Na treatment. We expressed, purified and assayed the activity of recombinant UGT proteins in vitro and identified PvUGT96C10 as the enzyme responsible for the glycosylation of HMDNBS in switchgrass. Overexpression of PvUGT96C10 in switchgrass significantly alleviated 2,4-DNT-3-SO3Na-induced plant growth inhibition. Notably, PvUGT96C10-overexpressing transgenic switchgrass plants removed 83.1% of 2,4-DNT-3-SO3Na in liquid medium after 28 days, representing a 3.2-fold higher removal rate than that of control plants. This work clarifies the DNTS detoxification mechanism in plants for the first time, suggesting that PvUGT96C10 is crucial for DNTS degradation. Our results indicate that PvUGT96C10-overexpressing plants may hold great potential for the phytoremediation of TNT red water-contaminated soils.
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Biodegradação Ambiental , Glicosiltransferases , Panicum , Panicum/genética , Panicum/metabolismo , Panicum/enzimologia , Glicosiltransferases/metabolismo , Glicosiltransferases/genética , Dinitrobenzenos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Poluentes do Solo/metabolismoRESUMO
Flavonoids are usually present in forms of glucosides in plants, which could be catabolized by ß-glucosidase (BGLU) to form their corresponding flavonoid aglycones. In this study, we isolated three abiotic-responsive BGLU genes (MtBGLU17, MtBGLU21 and MtBGLU22) from Medicago truncatula, and found only the recombinant MtBGLU17 protein could catalyse the hydrolysis of flavonoid glycosides. The recombinant MtBGLU17 protein is active towards a variety of flavonoid glucosides, including glucosides of flavones (apigenin and luteolin), flavonols (kaempferol and quercetin), isoflavones (genistein and daidzein) and flavanone (naringenin). In particular, the recombinant MtBGLU17 protein preferentially hydrolyses flavonoid-7-O-glucosides over their corresponding 3-O-glucosides. The content of luteoin-7-O-glucoside was reduced in the MtBGLU17 overexpression plants but increased in the Tnt-1 insertional mutant lines, whereas luteoin content was increased in the MtBGLU17 overexpression plants but reduced in the Tnt-1 insertional mutant lines. Under drought and salt (NaCl) treatment, the MtBGLU17 overexpression lines showed relatively higher DPPH content, and higher CAT and SOD activity than the wild type control. These results indicated that overexpression lines of MtBGLU17 possess higher antioxidant activity and thus confer drought and salt tolerance, implying MtBGLU17 could be potentially used as a candidate gene to improve plant abiotic stress tolerance.
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Antioxidantes , Secas , Flavonoides , Medicago truncatula , Proteínas de Plantas , Tolerância ao Sal , beta-Glucosidase , Medicago truncatula/genética , Medicago truncatula/enzimologia , Medicago truncatula/metabolismo , Medicago truncatula/fisiologia , Flavonoides/metabolismo , Antioxidantes/metabolismo , beta-Glucosidase/metabolismo , beta-Glucosidase/genética , Tolerância ao Sal/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de PlantasRESUMO
Medicago truncatula is a model legume for fundamental research on legume biology and symbiotic nitrogen fixation. Tnt1, a retrotransposon from tobacco, was used to generate insertion mutants in M. truncatula R108. Approximately 21 000 insertion lines have been generated and publicly available. Tnt1 retro-transposition event occurs during somatic embryogenesis (SE), a pivotal process that triggers massive methylation changes. We studied the SE of M. truncatula R108 using leaf explants and explored the dynamic shifts in the methylation landscape from leaf explants to callus formation and finally embryogenesis. Higher cytosine methylation in all three contexts of CG, CHG, and CHH patterns was observed during SE compared to the controls. Higher methylation patterns were observed in assumed promoter regions (~2-kb upstream regions of transcription start site) of the genes, while lowest was recorded in the untranslated regions. Differentially methylated promoter region analysis showed a higher CHH methylation in embryogenesis tissue samples when compared to CG and CHG methylation. Strong correlation (89.71%) was identified between the differentially methylated regions (DMRs) and the site of Tnt1 insertions in M. truncatula R108 and stronger hypermethylation of genes correlated with higher number of Tnt1 insertions in all contexts of CG, CHG, and CHH methylation. Gene ontology enrichment and KEGG pathway enrichment analysis identified genes and pathways enriched in the signal peptide processing, ATP hydrolysis, RNA polymerase activity, transport, secondary metabolites, and nitrogen metabolism pathways. Combined gene expression analysis and methylation profiling showed an inverse relationship between methylation in the DMRs (regions spanning genes) and the expression of genes. Our results show that a dynamic shift in methylation happens during the SE process in the context of CG, CHH and CHG methylation, and the Tnt1 retrotransposition correlates with the hyperactive methylation regions.
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Metilação de DNA , Regulação da Expressão Gênica de Plantas , Medicago truncatula , Técnicas de Embriogênese Somática de Plantas , Retroelementos , Medicago truncatula/genética , Medicago truncatula/metabolismo , Retroelementos/genética , Genoma de Planta/genética , Regiões Promotoras Genéticas/genéticaRESUMO
Soil pollution by TNT(2,4,6-trinitrotoluene), RDX(hexahydro-1,3,5-trinitro-1,3,5-triazacyclohexane), and HMX(octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), resulting from the use of explosives, poses significant challenges, leading to adverse effects such as toxicity and alteration of microbial communities. Consequently, there is a growing need for effective bioremediation strategies to mitigate this damage. This review focuses on Microbial and Bio-omics perspectives within the realm of soil pollution caused by explosive compounds. A comprehensive analysis was conducted, reviewing 79 articles meeting bibliometric criteria from the Web of Science and Scopus databases from 2013 to 2023. Additionally, relevant patents were scrutinized to establish a comprehensive research database. The synthesis of these findings serves as a critical resource, enhancing our understanding of challenges such as toxicity, soil alterations, and microbial stress, as well as exploring bio-omics techniques like metagenomics, transcriptomics, and proteomics in the context of environmental remediation. The review underscores the importance of exploring various remediation approaches, including mycorrhiza remediation, phytoremediation, bioaugmentation, and biostimulation. Moreover, an examination of patented technologies reveals refined and efficient processes that integrate microorganisms and environmental engineering. Notably, China and the United States are pioneers in this field, based on previous successful bioremediation endeavors. This review underscores research's vital role in soil pollution via innovative, sustainable bioremediation for explosives.
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Background: Hepatopancreato and biliary (HPB) tumors represent some of the leading cancer-related causes of death worldwide, with the majority of patients undergoing surgery in the context of a multimodal treatment strategy. Consequently, the implementation of an accurate risk stratification tool is crucial to facilitate informed consent, along with clinical decision making, and to compare surgical outcomes among different healthcare providers for either service evaluation or clinical audit. Perioperative troponin levels have been proposed as a feasible and easy-to-use tool in order to evaluate the risk of postoperative myocardial injury and 30-day mortality. The purpose of the present study is to validate the perioperative troponin levels as a prognostic factor regarding postoperative myocardial injury and 30-day mortality in Greek adult patients undergoing HPB surgery. Method: In total, 195 patients undergoing surgery performed by a single surgical team in a single tertiary hospital (2020-2022) were included. Perioperative levels of troponin before surgery and at 24 and 48 h postoperatively were assessed. Model accuracy was assessed by observed-to-expected (O:E) ratios, and area under the receiver operating characteristic curve (AUC). Survival at one year postoperatively was compared between patients with high and normal TnT levels at 24 h postoperatively. Results: Thirteen patients (6.6%) died within 30 days of surgery. TnT levels at 24 h postoperatively were associated with excellent discrimination and provided the best-performing calibration. Patients with normal TnT levels at 24 h postoperatively were associated with higher long-term survival compared to those with high TnT levels. Conclusions: TnT at 24 h postoperatively is an efficient risk assessment tool that should be implemented in the perioperative pathway of patients undergoing surgery for HPB cancer.
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This paper presents the development and optimization of a cost-effective paper electrochemical sensor for the detection of TNT using Fe3O4-Au core-shell nanoparticles modified with cysteamine (Fe3O4@Au/CA). The sensor was constructed by modifying a graphite paste with the aforementioned nanoparticles, which facilitated the formation of a Meisenheimer complex between cysteamine and TNT as an electron donor and an electron acceptor, respectively. The central composite design was employed to optimize four key parameters pH, modifier percentage, contact time, and buffer type to enhance the performance of the sensor. The detection limit was found to be 0.5 nM of TNT, while the linear range of the electrode response spanned from 0.002 µM to 10 µM. The simplicity and low cost of the sensor make it highly attractive for practical applications, particularly in scenarios where rapid and on-site TNT detection is required.
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Plant structure has a large influence on crop yield formation, with branching and plant height being the important factors that make it up. We identified a gene, MtTCP18, encoding a TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP) transcription factor highly conserved with Arabidopsis gene BRC1 (BRANCHED1) in Medicago truncatula. Sequence analysis revealed that MtTCP18 included a conserved basic helix-loop-helix (BHLH) motif and R domain. Expression analysis showed that MtTCP18 was expressed in all organs examined, with relatively higher expression in pods and axillary buds. Subcellular localization analysis showed that MtTCP18 was localized in the nucleus and exhibited transcriptional activation activity. These results supported its role as a transcription factor. Meanwhile, we identified a homozygous mutant line (NF14875) with a mutation caused by Tnt1 insertion into MtTCP18. Mutant analysis showed that the mutation of MtTCP18 altered plant structure, with increased plant height and branch number. Moreover, we found that the expression of auxin early response genes was modulated in the mutant. Therefore, MtTCP18 may be a promising candidate gene for breeders to optimize plant structure for crop improvement.
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The explosive compound 2,4,6-trinitrotoluene (TNT) is well known as a major component of munitions. In addition to its potential carcinogenicity and mutagenicity in humans, recent reports have highlighted TNT toxicities in diverse organisms due to its occurrence in the environment. These toxic effects have been linked to the intracellular metabolism of TNT, which is generally characterised by redox cycling and the generation of noxious reactive molecules. The reactive intermediates formed, such as nitroso and hydroxylamine compounds, also interact with oxygen molecules and cellular components to cause macromolecular damage and oxidative stress. The current review aims to highlight the crucial role of TNT metabolism in mediating TNT toxicity, via increased generation of reactive oxygen species. Cellular proliferation of reactive species results in depletion of cellular antioxidant enzymes, DNA and protein adduct formation, and oxidative stress. While TNT toxicity is well known, its ability to induce oxidative stress, resulting from its reductive activation, suggests that some of its toxic effects may be caused by its reactive metabolites. Hence, further research on TNT metabolism is imperative to elucidate TNT-induced toxicities.
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Estresse Oxidativo , Espécies Reativas de Oxigênio , Trinitrotolueno , Trinitrotolueno/metabolismo , Trinitrotolueno/toxicidade , Humanos , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ativação Metabólica , Animais , Substâncias Explosivas/metabolismo , Substâncias Explosivas/toxicidade , OxirreduçãoRESUMO
As a typical energetic compound widely used in military activities, 2,4,6-trinitrotoluene (TNT) has attracted great attention in recent years due to its heavy pollution and wide distribution in and around the training facilities, firing ranges, and demolition sites. However, the subcellular targets and the underlying toxic mechanism of TNT remain largely unknown. In this study, we explored the toxic effects of TNT biological reduction on the mitochondrial function and homeostasis in Caenorhabditis elegans (C. elegans). With short-term exposure of L4 larvae, 10-1000 ng/mL TNT reduced mitochondrial membrane potential and adenosine triphosphate (ATP) content, which was associated with decreased expression of specific mitochondrial complex involving gas-1 and mev-1 genes. Using fluorescence-labeled transgenic nematodes, we found that fluorescence expression of sod-3 (muls84) and gst-4 (dvls19) was increased, suggesting that TNT disrupted the mitochondrial antioxidant defense system. Furthermore, 10 ng/mL TNT exposure increased the expression of the autophagy-related gene pink-1 and activated mitochondrial unfolded protein response (mt UPR), which was indicated by the increased expression of mitochondrial stress activated transcription factor atfs-1, ubiquitin-like protein ubl-5, and homeobox protein dve-1. Our findings demonstrated that TNT biological reduction caused mitochondrial dysfunction and the development of mt UPR protective stress responses, and provided a basis for determining the potential risks of energetic compounds to living organisms.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Mitocôndrias , Trinitrotolueno , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Trinitrotolueno/toxicidade , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Trifosfato de Adenosina/metabolismoRESUMO
Layers of TiO2 nanotubes formed by the anodization process represent an area of active research in the context of innovative energy conversion and storage systems. Titanium nanotubes (TNTs) have attracted attention because of their unique properties, especially their high surface-to-volume ratio, which makes them a desirable material for various technological applications. The anodization method is widely used to produce TNTs because of its simplicity and relative cheapness; the method enables precise control over the thickness of TiO2 nanotubes. Anodization can also be used to create decorative and colored coatings on titanium nanotubes. In this study, a combined structure including anodic TiO2 nanotubes and SrTiO3 particles was fabricated using chemical synthesis techniques. TiO2 nanotubes were prepared by anodizing them in ethylene glycol containing NH4F and H2O while applying a voltage of 30 volts. An anode nanotube array heat-treated at 450 °C was then placed in an autoclave filled with dilute SrTiO3 solution. Scanning electron microscopy (SEM) analysis showed that the TNTs were characterized by clear and open tube ends, with an average outer diameter of 1.01 µm and an inner diameter of 69 nm, and their length is 133 nm. The results confirm the successful formation of a structure that can be potentially applied in a variety of applications, including hydrogen production by the photocatalytic decomposition of water under sunlight.
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INTRODUCTION: The impact of residential green spaces on cardiovascular health in older adults remains uncertain. METHODS: Cohort study involving 2114 adults aged ≥ 65 years without cardiovascular disease (CVD), residing in five dense municipalities (Prince et al., 2015) of the Madrid region and with detailed characterization of their socioeconomic background, health behaviors, CVD biological risk factors, and mental, physical, and cognitive health. Greenness exposure was measured using the Normalized Difference Vegetation Index (NDVI) at varying distances from participants' homes. Traffic exposure, neighborhood environment, neighborhood walkability, and socioeconomic deprivation at the census level were also assessed. Serum N-terminal pro-B-type natriuretic peptide (NT-ProBNP), high-sensitivity troponin T (hs-TnT), interleukin 6 (IL-6), and Growth Differentiation Factor 15 (GDF-15) were measured at baseline, and incident CVD events identified through electronic medical records (International Classification of Primary Care-2 codes K74, K75, K77, K90, and K92). RESULTS: After adjusting for sex, age, educational attainment, financial hardship and socioeconomic deprivation at the census level, an interquartile range (IQR) increase in NDVI at 250, 500, 750, and 1000 m around participants' homes was associated with mean differences in ProBNP of -5.56 % (95 %CI: -9.77; -1.35), -5.05 % (-9.58; -0.53), -4.24 % (-8.19, -0.19), and -4.16 % (-7.59; -0.74), respectively; and mean differences in hs-TnT among diabetic participants of -8.03 % (95 %CI: -13.30; -2.77), -9.52 % (-16.08; -2.96), -8.05 % (-13.94, -2.16) and -5.56 % (-10.75; -0.54), respectively. Of similar magnitude, although only statistically significant at 250 and 500 m, were the observed lower IL-6 levels with increasing greenness. GDF-15 levels were independent of NDVI. In prospective analyses (median follow-up 6.29 years), an IQR increase in residential greenness at 500, 750, and 1000 m was associated with a lower risk of incident CVD. The variables that contributed most to the apparent beneficial effects of greenness on CVD were lower exposure to traffic, improved cardiovascular risk factors, and enhanced physical performance. Additionally, neighborhood walkability and increased physical activity were notable contributors among individuals with diabetes. CONCLUSION: Increased exposure to residential green space was associated with a moderate reduction in CVD risk in older adults residing in densely populated areas.
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Doenças Cardiovasculares , Diabetes Mellitus , Humanos , Idoso , Doenças Cardiovasculares/epidemiologia , Fator 15 de Diferenciação de Crescimento , Parques Recreativos , Estudos de Coortes , Estudos Prospectivos , Fatores de Risco , Interleucina-6 , Fatores de Risco de Doenças Cardíacas , BiomarcadoresRESUMO
The xenobiotic 2,4,6-trinitrotoluene (TNT) is a highly persistent environmental contaminant, whose biotransformation by microorganisms has attracted renewed attention. In previous research, we reported the discovery of Pseudomonas sp. TNT3, the first described Antarctic bacterium with the ability to biotransform TNT. Furthermore, through genomic analysis, we identified distinctive features in this isolate associated with the biotransformation of TNT and other xenobiotics. However, the metabolic pathways and genes active during TNT exposure in this bacterium remained unexplored. In the present transcriptomic study, we used RNA-sequencing to investigate gene expression changes in Pseudomonas sp. TNT3 exposed to 100 mg/L of TNT. The results showed differential expression of 194 genes (54 upregulated and 140 downregulated), mostly encoding hypothetical proteins. The most highly upregulated gene (> 1000-fold) encoded an azoreductase enzyme not previously described. Other significantly upregulated genes were associated with (nitro)aromatics detoxification, oxidative, thiol-specific, and nitrosative stress responses, and (nitro)aromatic xenobiotic tolerance via efflux pumps. Most of the downregulated genes were involved in the electron transport chain, pyrroloquinoline quinone (PQQ)-related alcohol oxidation, and motility. These findings highlight a complex cellular response to TNT exposure, with the azoreductase enzyme likely playing a crucial role in TNT biotransformation. Our study provides new insights into the molecular mechanisms of TNT biotransformation and aids in developing effective TNT bioremediation strategies. To the best of our knowledge, this report is the first transcriptomic response analysis of an Antarctic bacterium during TNT biotransformation.
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Trinitrotolueno , Trinitrotolueno/metabolismo , Pseudomonas/genética , Pseudomonas/metabolismo , Xenobióticos/metabolismo , Biotransformação , Bactérias/metabolismo , Biodegradação Ambiental , Perfilação da Expressão GênicaRESUMO
An interesting biotin-linked-antigen-Sandwich-ELISA was developed (BLA-S-ELISA), which based on the captured Trinitrophenol-Biotin (TNP-Biotin) molecule between the immobilised monovalent antibody and enzyme-conjugated streptavidin. Monoclonal anti-Trinitrotoluene single chain fragment antibody (anti-TNT-scFv) was cloned and expressed in E. coli cells, and then used as an immobilised component in an assay. Thereafter, the previously synthesised TNP-Biotin was added as antigen followed by the addition of streptavidin-horseradish peroxidase (streptavidin-HRP) conjugate which led finally to the formation of a three-component system (antibody/TNP-Biotin/streptavidin-HRP). The assay was performed with a range of different dilutions of TNP-Biotin to establish its minimal detectable concentration. The detection limit of TNP-Biotin was 4 ngmL-1 (i.e. 200 pg or 0.42 pmol antigen calculated on the basis of 50 µL sample or 8.4 nM expressed in concentration units). According to our best knowledge, this is the very first time for any model antigen to be detected with such a form of biotin-streptavidin sandwich-assay.
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BACKGROUND: Recently, there has been significant interest in, and adoption of, total neoadjuvant therapy (TNT) for locally advanced rectal cancer (LARC). We designed the present study to assess the robustness of the randomized controlled trials (RCTs) evaluating contemporary TNTs for LARC using the fragility index (FI). MATERIALS AND METHODS: Relevant articles were identified through a review article by Johnson et al. in the Canadian Journal of Surgery. Dichotomous outcomes within these RCTs were eligible for inclusion if the reported effect size had a p-value < 0.05. The main outcome was FI for each included outcome. Walsh et al.'s method of calculating FI was utilized. Correlations between FI and research characteristics were assessed using the Spearman's rank correlation coefficients. Risk of bias was assessed using Cochrane recommended tools. RESULTS: Ten RCTs were identified with 25 outcomes having statistically significant differences between groups. Eleven outcomes were time-to-event outcomes, while the remainder were dichotomous outcomes. Approximately half (n = 13) were oncologic outcomes. The median FI was 2 (interquartile range [IQR] 1-16). The number of patients lost to follow-up exceeded the FI in 17 outcomes (68.0 %) and thus these results were considered "fragile". Lower FI was associated with high risk of bias (rho = -0.5594) and greater loss to follow-up (rho = -0.4394), while higher FI was associated with large study size (rho = 0.5120). CONCLUSIONS: The robustness of outcomes from trials assessing TNT for LARC was found to be questionable. Most outcomes were fragile, as determined by the FI. This survey is limited by the number of included studies.
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Terapia Neoadjuvante , Neoplasias Retais , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Retais/terapia , Neoplasias Retais/patologiaRESUMO
2,4,6-Trinitrotoluene (TNT) is a highly toxic nitroaromatic explosive known for its environmental consequences, contaminating soil and groundwater throughout its life cycle, from production to disposal. Therefore, the urgency of developing innovative and ecological strategies to remedy the affected areas is recognized. This study reports, for the first time, the enzymatic biotransformation of TNT by a cocktail of native laccases from Pycnoporus sanguineus CS43. The laccases displayed efficient TNT conversion under both oxygenic and non-oxygenic conditions, achieving biotransformation rates of 80% and 87% within 48 h at a temperature of 60 °C and pH 7. Preliminary kinetic constants were calculated with the laccase cocktail, being a Vmax of 1.133 µM min-1 and 0.2984 µM min-1, and the Km values were 1586 µM and 458 µM, in an oxygenic and non-oxygenic atmosphere, respectively. High-performance liquid chromatography-mass spectrometry (HPLC/MS) confirmed the formation of amino dinitrotoluene isomers and hydroxylamine isomers as biotransformation products. In summary, this study suggests the potential application of laccases for the direct biotransformation of recalcitrant compounds like TNT, offering an environmentally friendly approach to address contamination issues.
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Polyporaceae , Trinitrotolueno , Lacase/química , Biotransformação , Polyporaceae/metabolismoRESUMO
AIMS: High-sensitive troponin T (hs-TnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and C-reactive protein (CRP) are established prognostic biomarkers for cardiovascular (CV) morbidity and mortality and frequently used in symptomatic and/or hospitalized adults with congenital heart disease (ACHD). Their prognostic value in clinically stable ACHD has not yet been well established. This study investigates the predictive value of hs-TnT, NT-proBNP, and CRP for survival and CV events in stable ACHD. METHODS AND RESULTS: In this prospective cohort study, 495 outpatient ACHD (43.9 ± 10.0 years, 49.1% female) underwent venous blood sampling including hs-TnT, NT-proBNP, and CRP. Patients were followed up for survival status and the occurrence of CV events. Survival analyses were performed with Cox proportional hazards regression analysis and Kaplan-Meier curves. During a mean follow-up of 2.8 ± 1.0 years, 53 patients (10.7%) died or reached a cardiac-related endpoint including sustained ventricular tachycardia, hospitalization with cardiac decompensation, ablation, interventional catheterization, pacer implantation, or cardiac surgery. Multivariable Cox regression revealed hs-TnT (P = 0.005) and NT-proBNP (P = 0.018) as independent predictors of death or cardiac-related events in stable ACHD, whilst the prognostic value of CRP vanished after multivariable adjustment (P = 0.057). Receiver-operator characteristic curve analysis identified cut-off values for event-free survival of hs-TnT ≤9 ng/L and NT-proBNP ≤200 ng/L. Patients with both increased biomarkers had a 7.7-fold (confidence interval 3.57-16.40, P < 0.001) higher risk for death and cardiac-related events compared with patients without elevated blood values. CONCLUSION: Subclinical values of hs-TnT and NT-proBNP are a useful, simple, and independent prognostic tool for adverse cardiac events and survival in stable outpatient ACHD. REGISTRATION: German Clinical Trial Registry DRKS00015248.