Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Environ Manage ; 356: 120623, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38518494

RESUMO

The environmental pollution caused by azo dyes at high temperatures has become an urgent problem. However, little attention has been paid to decolorizing azo dyes by thermophilic consortiums. In this study, a thermophilic bacterial consortium (BCGR-T) mainly composed of two genera, namely, Caldibacillus (70.90%) and Aeribacillus (17.63%) was first enriched, which can decolorize Brilliant Crocein GR (BCGR) at high temperatures (50-75 °C), pH values of 6∼8, dye concentrations (100-400 mg/L) and salinities (1-5%, w/v). The enzyme activity results showed that the azoreductase activity was nearly 8.8 times that of the control (p < 0.01), and the intracellular lignin peroxidase was also highly expressed with enzyme activity of 5.64 U (min-1 mg-1 protein) (p < 0.05), indicated that both azoreductase and intracellular lignin peroxidase played an important part in the decolorization process. Furthermore, seven new intermediate metabolic products, including aniline, phthalic acid, 2-carboxy benzaldehyde, phenylacetic acid, benzoic acid, toluene, and 4-methyl-hexanoic acid, were identified. In addition, functional genes related with the azo dye decolorization, such as those encoding the azoreductase, laccase, FMN reductase, NADPH-/NADH-quinone oxidoreductases and NADPH-/NADH dehydrogenases, catechol dioxygenase, homogentisate 1,2-dioxygenase, protocatechuate 3,4-dioxygenase, gentisate 1,2-dioxygenase, azobenzene reductase, naphthalene 1,2-dioxygenase, benzoate/toluate 1,2-dioxygenase, and anthranilate 1,2-dioxygenase and so on were found in the metagenome of the consortium BCGR-T. Finally, a new decolorization pathway of the thermophilic consortium BCGR-T was proposed. In addition, the phototoxicity of BCGR decreased after decolorization. Overall, the thermophilic consortium BCGR-T could be a promising candidate in the treatment of high concentration azo dye wastewater at high temperatures.


Assuntos
Dioxigenases , NAD , Naftalenossulfonatos , NADP , Biodegradação Ambiental , Compostos Azo , Corantes
2.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38535483

RESUMO

The simulator is an indispensable device for the study of high-altitude electromagnetic pulse (HEMP) effects. In order to improve the quality of the electric field waveforms of the HEMP simulator, we carried out simulation and experimental studies for the biconical-wire grid antenna. A new bicone-wire grid antenna HEMP simulator was designed by using skeletonized cones instead of solid cones, which can substantially improve the mobility of the simulator. The effects of different aspect ratios and different cone structures of the simulator on the waveform and distribution characteristics of the electric field were analyzed. The accuracy of the simulation results was verified by testing the bicone-wire grid antenna simulator with the new structure. The results obtained are as follows: First, the simulator can provide a HEMP environment compliant with the International Electrotechnical Commission (IEC) standard in an area of 5 × 6 × 2 m3. Second, the simulator possesses optimal waveform quality and working space among simulators with different aspect ratios. Finally, the influence of using skeletonized cones instead of solid cones on the simulator's electric field waveforms is negligible, and the mobility of the new simulator is significantly improved compared to the original simulator.

3.
Rev Sci Instrum ; 94(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37787632

RESUMO

In this paper, the effects of initial electrons generation approaches on nanosecond pulsed breakdown characteristics are analyzed. Based on the numerical simulations with a 3D PIC-MCC model, the impacts of field-enhancement factor and initial electron concentration on nanosecond pulsed breakdown characteristics are investigated. Three types of switches are designed and subjected to testing under pulse voltages with rise times of 40, 70, and 120 ns, respectively. The results can be summarized as follows. First, the field-enhancement factor and initial electron concentration have significant influences on the development of the discharge channel. Second, the cathode-grooved self-triggered switch exhibits lower breakdown time delay jitter than the hemispherical self-breakdown switch at low pressure, while the differences in jitter between the two switches become negligible at high pressure. Third, the cathode-grooved self-triggered switch shows a lower breakdown time delay jitter compared to the pre-ionization self-triggered switch for pulse voltages with rise times of 40 and 70 ns. Conversely, this trend reverses for pulse voltage with a rise time of 120 ns. Finally, the breakdown time delay jitter for both the cathode-grooved self-triggered switch and the pre-ionization self-triggered switch has been reduced, and both switches are suitable for different operating requirements and conditions.

4.
J Colloid Interface Sci ; 651: 929-937, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37579667

RESUMO

It is very necessary to design a high-capacity and stable Bi2O3 anode for nickel-bismuth (Ni//Bi) batteries. In this work, a stable α- and ß- phase Bi2O3 heterojunction nanocomposite (α/ß - Bi2O3) was successfully prepared via a simple "space-confined" strategy and it was used as a superior anode for nickel-bismuth (Ni//Bi) battery. The α/ß-Bi2O3 obtained by using MCM-41 as a space-confined template possesses a stable structure and enhanced charge transfer capability. Such superior traits vest the designed α/ß-Bi2O3 electrode with high specific capacity (235 mAh g-1 at 1 A g-1), extraordinary rate performance (137 mAh g-1 at 40 A g-1, and ∼58% capacity retention vs 1 A g-1), and excellent cyclic durability (75% capacity retention after 5000 cycles). Such performances are far superior to that of mono-phase α-Bi2O3 and ß-Bi2O3 electrodes. Furthermore, an excellent Ni//Bi battery with outstanding energy density (∼155 Wh kg-1) and long cycle life was assembled using the obtained α/ß-Bi2O3 electrode and a NiC2O4 electrode as anode and cathode, respectively (NiC2O4//α/ß-Bi2O3). This work opens a new alternative strategy for the rational design of efficient electrodes for reliable aqueous rechargeable batteries.

5.
J Hazard Mater ; 448: 130976, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36860052

RESUMO

The main cause of groundwater nitrate contamination is the continual downward migration of dissolved nitrogen (N) in vadose zone with leachate. In recent years it has been found that dissolved organic N (DON) rise to forefront due to its great migration capacity and environmental effects. However, it remains unknown how the transformation behaviors of DONs with different properties in vadose zone profile may impact N forms distribution and groundwater nitrate contamination. To address the issue, we conducted a series of 60-day microcosm incubation experiments to investigate the effects of various DONs transformation behaviors on the distribution of N forms, microbial communities, and functional genes. The results revealed that urea and amino acids mineralized immediately after substrates addition. By contrast, amino sugars and proteins caused less dissolved N throughout entire incubation period. The transformation behaviors could substantially alter the microbial communities. Moreover, we discovered that amino sugars remarkably increased the absolute abundances of denitrification function genes. These results delineated that DONs with unique characteristics (such as amino sugar) promoted different N geochemical processes in distinct ways: different contributions to nitrification and denitrification. This can provide new insights for nitrate non-point source pollution control in groundwater.


Assuntos
Água Subterrânea , Nitratos , Nitrificação , Desnitrificação , Amino Açúcares
6.
Chemistry ; 29(20): e202203500, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36617812

RESUMO

Alkaline Bi//Zn batteries with superb safety, low cost, and high power density are promising candidates for large-scale electrical energy storage. However, their developments are severely limited by the Bi-based cathode as the unsatisfying capacity and cycle life. Herein, an innovative multistage cubic nanospheres Bi12 SiO20 (MCS-Bi12 SiO20 ) is successfully synthesized by a simple calcination method, which shows excellent energy storage performances of superior specific capacity (294 mAh g-1 at 0.5 A g-1 ) and outstanding rate capability (134 mAh g-1 at 12 A g-1 ). When coupled with Zn anode a superior MCS-Bi12 SiO20 //Zn is fabricated, which delivers a high energy density of 247.5 Wh kg-1 at the power density of 375 W kg-1 . Additionally, the MCS-Bi12 SiO20 //Zn battery shows excellent cycle life, which reserves more than 100 % of its original capacity after 5000 cycles. Such performance is higher than previously reported Bi//Zn battery and most other Zn batteries. This is the first example of using Bi12 SiO20 as cathode for RAZBs, which may provide highly promising material towards better Bi//Zn battery.

7.
J Inflamm Res ; 14: 6783-6798, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34916825

RESUMO

BACKGROUND: Plasma exosome-derived microRNA (miRNA) profiles following thermal injury and their relationship with gene expression derangements in burned skin remain unexplored. This study focused on the identification of key miRNA-mRNA axes in potential blood-to-tissue interactions at early burn stage. METHODS: Plasma exosomes were obtained from 6 severe burn patients 4-7 days post injury and 6 healthy volunteers. Next-generation sequencing (NGS) of exosomal small RNAs presented the differentially expressed miRNAs (DEMs). Target genes of the DEMs were predicted in the mirDIP database. Dataset GSE8056 was enrolled to acquire differentially expressed genes (DEGs) in burned skin compared to normal skin. Overlap between the DEGs and target genes of the DEMs were focus genes. The protein-protein interaction (PPI) network and enrichment analyses of the focus genes demonstrated hub genes and suggested underlying mechanisms and pathways. The hub genes and upstream DEMs were selected to construct key miRNA-mRNA axes. RESULTS: The NGS of plasma exosome-derived small RNAs identified 85 DEMs (14 downregulated miRNAs and 71 upregulated miRNAs) with 12,901 predicted target genes. Dataset GSE8056 exhibited 1861 DEGs in partial-thickness burned skins 4-7 days postburn. The overlap between DEGs and target genes of DEMs displayed 1058 focus genes. The top 9 hub genes (CDK1, CCNB1, CCNA2, BUB1B, PLK1, KIF11, AURKA, NUSAP1 and CDCA8) in the PPI network of the focus genes pointed to 16 upstream miRNAs in DEMs, including 4 downregulated miRNAs (hsa-miR-6848-3p, has-miR-4684-3p, has-miR-4786-5p and has-miR-365a-5p) and 12 upregulated miRNAs (hsa-miR-6751-3p, hsa-miR-718, hsa-miR-4754, hsa-miR-6754-3p, hsa-miR-4739, hsa-miR-6739-5p, hsa-miR-6884-3p, hsa-miR-1224-3p, hsa-miR-6878-3p, hsa-miR-6795-3p, hsa-miR-550a-3p, and hsa-miR-550b-3p). A key miRNA-mRNA network in potential blood-to-tissue interactions at early burn stage was therefore constructed. CONCLUSION: An NGS and bioinformatic analysis in the study identified key miRNA-mRNA axes in potential blood-to-tissue interactions at early burn stage, suggesting plasma exosome-derived miRNAs may impact on the alteration patterns of gene expressions in a burn wound.

8.
J Inflamm Res ; 14: 519-526, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33658827

RESUMO

INTRODUCTION: Neutrophil-to-lymphocyte ratio (NLR) is a marker of inflammation. This study aimed to evaluate the potential role of NLR to predict 90-day mortality. METHODS: Data of 577 patients with burns over 30% of total body surface area were collected and retrospectively analyzed. The risk factors for 90-day mortality were evaluated using logistic regression analyses. Receiver operating characteristic (ROC) curve analysis of the 3rd day NLR was performed and the optimal cut-off value was calculated. The 90-day mortality rates were compared between high and low NLR groups using Kaplan-Meier analysis. RESULTS: Age, mechanical ventilation, burn index, 3rd day NLR, and 7th day red blood cell and platelet (PLT) counts were found to be independent predictive values for 90-day mortality. In contrast, percentage of total body surface area burned, inhalation injury, 1st day white blood cell and neutrophil counts, the 3rd day lymphocytes and PLT counts, and 7th day hemoglobin level were not independently associated with 90-day mortality. The area under the ROC curve of the 3rd day NLR for severe burn-delayed death prediction was 0.665 (95% confidence interval, 0.591-0.739), and the optimal cut-off value of the 3rd day NLR was 10.50. The 90-day mortality rates differed significantly between the NLR >10.5 group and the NLR ≤ 10.5 group (17.03% vs 5.92%, respectively; P < 0.01). CONCLUSION: These results suggested that the 3rd day NLR was associated with an increased risk of death in severely burned patients; thus, it can provide useful information to predict 90-day mortality.

9.
Environ Toxicol Pharmacol ; 80: 103487, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32889110

RESUMO

In the new drugs, greater than 90 % of active pharmaceutical ingredients (APIs) or marketed drugs have poor solubility and bioavailability, which restrict the development of pharmaceutical preparations. The use of crystalline molecular complexes (CMCs) involving API and biocompatible precursors to improve solubility has become a shortcut for new drug development. Most of the new drugs registered in CMC form are from postmarketing drugs, and the interaction between these drugs and cytochrome P-450 (CYP) enzymes is well documented. However, it is unclear whether the interactions between CMCs of postmarketing drugs and CYP enzymes should be re-evaluated. To clarify this problem, three dipfluzine (Dip)-based CMCs, including Dip-benzoic acid (BA) cocrystal, Dip-2-hydroxybenzoate (2HB) salt and Dip-4-hydroxybenzoate (4HB) salt-cocrystal, were chosen to investigate the interaction with CYP enzymes. Metabolites of Dip-based CMCs and cocktail probe drugs were measured via LC-MS/MS in the incubation reaction system comprising recombinant CYP enzymes (rCYPs) and human liver microsomes. Dip-based CMCs not only alter Dip-mediated inhibition or activation of CYP enzymes but also change the degree to which rCYPs are involved in Dip metabolism. Specifically, the inhibitory effects of Dip and Dip-HCl were increased compared with Dip-BA and Dip-2HB for CYP1A2; Dip-BA, Dip-2HB and Dip-4HB for CYP3A4; and Dip-BA for CYP2E1. The inhibitory effects of Dip and Dip-HCl were reduced compared with Dip-2HB and Dip-4HB for CYP2C19 and Dip-4HB for CYP2E1. The effects of the alterations of Dip CMCs on the interaction between Dip and CYP enzymes are not attributed to a simple superposition of Dip and the respective precursor and may be due to the presence of interaction forces between Dip and precursor molecules. These results are the first to provide preliminary experimental evidence that CMCs change the interaction between API and CYP enzymes. Moreover, these results further suggest the importance of re-evaluating interactions with CYP enzymes when CMC strategies are used to design new drugs and even for CMCs of postmarketing drugs with known metabolic characteristics.


Assuntos
Cinarizina/análogos & derivados , Sistema Enzimático do Citocromo P-450/metabolismo , Cinarizina/metabolismo , Cristalização , Humanos , Microssomos Hepáticos/metabolismo , Sais
10.
Environ Toxicol Pharmacol ; 79: 103430, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32544426

RESUMO

Identifying the metabolites of a drug has become an indispensable task in the development of new drugs. Dipfluzine (Dip) is a promising candidate for the treatment of cerebral vascular diseases and has 5 metabolites (M1∼M5) in rat urine and liver microsomes, but their biological activity is still unknown. Because selective cerebral vasodilation is a main role of Dip, we investigated the vasodilation of Dip and its 5 metabolites in isolated Sprague-Dawley (SD) male rat basilar arteries preconstricted with high-K+ or 5-HT. The results showed that only M1 possessed concentration-dependent inhibitory activity on the vasoconstriction of arteries with or without the endothelium, and M1 has a more potent vasodilatory effect than Dip on both contraction models. Like Dip, the vasodilatory mechanisms of M1 may be not only related to receptor-operated and voltage-dependent calcium ion channels of smooth muscle cells but also to the release of NO and EDHF from endothelial cells and the opening of Ca2+-activated K+ channels and ATP-sensitive potassium ion channels. Unlike Dip, the vasodilation mechanism of M1 is also related to the opening of voltage-sensitive K+ channel. Together with more selectivity to non-VDCC than Dip, this may partially explain why M1 has stronger vasodilatory effects than Dip. The mechanisms of vasodilation of Dip and M1 may result from the combined action of these or other factors, especially blocking non-endothelium dependent non-VDCC and endothelium dependent IKCa channels. These results point to the possibility that M1 provides synergism for the clinical use of Dip, which may inform the synthesis of new drugs.


Assuntos
Artéria Basilar/efeitos dos fármacos , Cinarizina/análogos & derivados , Vasodilatadores/farmacologia , Animais , Artéria Basilar/fisiologia , Cinarizina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Técnicas In Vitro , Masculino , Canais de Potássio/fisiologia , Ratos Sprague-Dawley , Vasodilatação/efeitos dos fármacos
11.
Sci Rep ; 7(1): 13720, 2017 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-29057939

RESUMO

Red blood cell distribution width (RDW), platelet count (PLT), and a RDW-to-PLT ratio (RPR) have been associated with inflammatory activity and adverse outcomes in many diseases. This study has aimed to investigate the association between these indicators and the mortality rate of severe burn patients. From 2008 to 2014, 610 cases of severe burn patients from two burn centers in eastern China were enrolled in this study. Eighty-eight patients died within 90 days after admission. The RDW, PLT, and RPR were studied through Cox regression analysis on the 3rd and 7th day. The RDW, PLT, and RPR values on the 3rd and 7th day were significantly associated with the outcomes of severe burn patients (P < 0.01). High RPR was significantly associated with a 90-day mortality rate at the two time points. However, the RDW and PLT did not provide independent predictive values. Our results indicated that the RPR values on the 3rd and 7th day were associated with the mortality rates of severe burn patients (P < 0.01). Meanwhile, the RDW and PLT values at these time points failed to provide independent values for burn mortality prediction. Thus, the RPR can serve as an independent and novel marker for mortality rates prediction in severe burn patients.


Assuntos
Queimaduras/sangue , Adulto , Biomarcadores/sangue , Queimaduras/mortalidade , Índices de Eritrócitos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prognóstico , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença , Análise de Sobrevida
12.
Burns ; 43(4): 839-845, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28041753

RESUMO

OBJECTIVE: Challenges persist in the reconstruction of the ankle and the foot with exposed tendons, joints, and bones as a result of severe burns and trauma. In flap elevation involving the sensitive superficial nerve, the local nerve was always sacrificed to obtain an anesthetic donor site; however, such a procedure introduced the possibility of painful neuromas. In this study, we present a desired clinical application of a modified reversed superficial peroneal artery flap, in which the superficial peroneal nerve is preserved. METHODS: From 2008 to 2015, 12 patients with ankle or foot defects were treated with the modified reversed superficial peroneal artery flap. The defects of the patients were caused by hot liquid scald (one patient), electrical injury (five patients), and trauma (six patients). The flap was utilized for covering defects on the ankle (seven patients) and the foot (five patients). The size of the flaps ranged from 4.0cm×6.0cm to 18.0cm×10.0cm. The superficial peroneal artery was involved in the flap, whereas the superficial peroneal nerve was spared by dedicate dissection. The reverse-flow flap was nourished by the superficial peroneal artery through the terminal peroneal artery perforator. RESULTS: The obtained outcomes were satisfactory functionally and aesthetically. The flaps in 11 patients survived completely without complications, whereas partial necrosis occurred in a 78-year-old patient when the flap survived a week later during follow up. CT angiography revealed the stenosis of the popliteal artery. The wound healed after interventional treatment involving placing a stent and changing the dressings. Basic functions and configurations were salvaged in all cases. All patients were completely satisfied with the proposed flap and suffered no paresthesia in their lower leg. CONCLUSION: Exhibiting beneficial characteristics such as reliable blood supply, favorable thickness, wide rotating arc, and retention of major vessels and the superficial peroneal nerve, the modified reversed superficial peroneal artery flap is useful in the reconstruction of ankle and foot defects that would not cause any hypoesthesia of the foot.


Assuntos
Traumatismos do Tornozelo/cirurgia , Queimaduras/cirurgia , Traumatismos do Pé/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos , Adolescente , Adulto , Idoso , Artérias , Criança , Feminino , Humanos , Hipestesia/prevenção & controle , Masculino , Pessoa de Meia-Idade , Nervo Fibular , Complicações Pós-Operatórias/prevenção & controle , Lesões dos Tecidos Moles/cirurgia , Ferimentos e Lesões/cirurgia , Adulto Jovem
13.
Chem Commun (Camb) ; 52(17): 3544-7, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26842808

RESUMO

A simple and effective one-step method is proposed for the fabrication of hollow periodic mesoporous organosilica spheres (HPMOSs). The obtained HPMOSs possess well-defined spherical morphology, uniform and tunable particle size, adjustable hollow void structure, and radially oriented mesochannels in their shells.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...