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1.
Environ Sci Technol ; 58(6): 2598-2614, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38291652

RESUMO

The widespread application of nanotechnology inevitably leads to an increased release of engineered nanoparticles (ENPs) into the environment. Due to their specific physicochemical properties, ENPs may interact with other contaminants and exert combined effects on the microbial community and metabolism of anaerobic digestion (AD), an important process for organic waste reduction, stabilization, and bioenergy recovery. However, the complicated interactions between ENPs and other contaminants as well as their combined effects on AD are often overlooked. This review therefore focuses on the co-occurrence of ENPs and cocontaminants in the AD process. The key interactions between ENPs and cocontaminants and their combined influences on AD are summarized from the available literature, including the critical mechanisms and influencing factors. Some sulfides, coagulants, and chelating agents have a dramatic "detoxification" effect on the inhibition effect of ENPs on AD. However, some antibiotics and surfactants increase the inhibition of ENPs on AD. The reasons for these differences may be related to the interactive effects between ENPs and cocontaminants, changes of key enzyme activities, adenosine triphosphate (ATP) levels, reactive oxygen species (ROS) production, and microbial communities. New scientific opportunities for a better understanding of the coexistence in real world situations are converging on the scale of nanoparticles.


Assuntos
Nanopartículas , Anaerobiose , Nanopartículas/química , Nanotecnologia , Espécies Reativas de Oxigênio
2.
Pharmacol Res ; 187: 106624, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36563868

RESUMO

Selenium has good antitumor effects in vitro, but the hypoxic microenvironment in solid tumors makes its clinical efficacy unsatisfactory. We hypothesized that the combination with oxygen therapy might improve the treatment efficacy of selenium in hypoxic tumors through the changes of redox environment. In this work, two selenium compounds, Na2SeO3 and CysSeSeCys, were selected to interrogate their therapeutic effects on hepatocellular carcinoma (HCC) under different oxygen levels. In tumor-bearing mice, both selenium compounds significantly inhibited the tumor growth, and combined with oxygen therapy further reduced the tumor volume about 50 %. In vitro HepG2 cell experiments, selenium induced autophagy and delayed apoptosis under hypoxia (1 % O2), while inhibited autophagy and accelerated apoptosis under hyperoxia (60 % O2). We found that, in contrast to hypoxia, the hyperoxic environment facilitated the H2Se, produced by the selenium metabolism in cells, to be rapidly oxidized to generate H2O2, leading to inhibit the expression level of Nrf2 and to increase that of phosphorylation of p38 and MKK4, resulting in inhibiting autophagy and accelerating apoptosis. Once the Nrf2 gene was knocked down, selenium compounds combined with hyperoxia treatment would further activate the MAPK signaling pathway and further increase apoptosis. These findings highlight oxygen can significantly enhance the anti-HCC effect of selenium compounds through regulating the Nrf2 and MAPK signaling pathways, thus providing novel therapeutic strategy for the hypoxic tumors and pave the way for the application of selenium in clinical treatment.


Assuntos
Carcinoma Hepatocelular , Hiperóxia , Neoplasias Hepáticas , Compostos de Selênio , Selênio , Animais , Camundongos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Selênio/farmacologia , Selênio/uso terapêutico , Compostos de Selênio/metabolismo , Compostos de Selênio/farmacologia , Compostos de Selênio/uso terapêutico , Peróxido de Hidrogênio/farmacologia , Transdução de Sinais , Apoptose , Hipóxia , Oxigênio , Microambiente Tumoral
3.
J Environ Manage ; 308: 114641, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35131705

RESUMO

Hydrogen production from waste-activated sludge (WAS) anaerobic fermentation is considered to be an effective method of resource recovery. However, the presence of a large number of complex organic compounds in sludge will affect the biological hydrogen production process. As an extensively applied prevalent anti-inflammatory drug, diclofenac (DCF) is inevitably released into the environment. However, the effect of diclofenac on hydrogen production from WAS anaerobic fermentation has not been fully investigated. This work therefore aims to comprehensively investigate the removal efficiency of DCF in mesophilic anaerobic fermentation of WAS and its effect on hydrogen yield. Experiment results showed that 32.5%-38.3% of DCF was degraded in the fermentation process when DCF concentration was ranged from 6 to 100 mg/kg TSS (total suspended solids). DCF at environmental level inhibited hydrogen production, the maximal hydrogen yield decreased from 24.2 to 15.3 mL/g VSS (volatile suspended solids) with an increase of DCF addition from 6 to 100 mg/kg TSS. This is because the presence of DCF caused inhibitions to acetogenesis and acidogenesis, the processes responsible for hydrogen production, probably due to that the polar groups of DCF (i.e., carboxyl group) could readily bind to active sites of [FeFe]- Hydrogenase. Besides, the microbial analysis revealed that DCF increased the microbial diversity but had few influences on the microbial structure.


Assuntos
Diclofenaco , Esgotos , Anaerobiose , Ácidos Graxos Voláteis , Fermentação , Hidrogênio , Concentração de Íons de Hidrogênio , Esgotos/química
4.
Bioresour Technol ; 347: 126366, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34838636

RESUMO

Producing methane from anaerobic co-digestion of kitchen waste and waste activated sludge has been widely implemented in real-world situations. However, the fate and impact of allyl isothiocyanate (AITC), a main active component in cruciferous vegetables, in the anaerobic co-digestion has never been documented. This study therefore aims to provide such supports. Experimental results exhibited that AITC was degraded completely by microorganisms and served as a substrate to produce methane. As AITC increased from 0 to 60 mg/L, the maximum methane production decreased from 285.1 to 35.8 mL/g VS, and the optimum digestion time was also prolonged. The mechanism study demonstrated that AITC induced cell apoptosis by modifying the physicochemical properties of cell membrane, which resulted in inhibitions to the procedure of anaerobic co-digestion. The high-throughput sequencing showed that AITC enriched the microorganism for degradation of complex organic compounds such as Bacillus, but lessened anaerobes involved in hydrolysis, acidogenesis, and methanogenesis.


Assuntos
Reatores Biológicos , Esgotos , Anaerobiose , Digestão , Isotiocianatos , Metano , Eliminação de Resíduos Líquidos
5.
World J Clin Cases ; 9(11): 2576-2583, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33889623

RESUMO

BACKGROUND: Immunoglobulin D (IgD) multiple myeloma (MM) is a rare subtype of MM and commonly occurs in younger subjects but at a later stage of the International Staging System (ISS) when admitted. As a special type of IgD myeloma, IgD-λ/λ biclonal MM is rarer. Its serum protein electrophoresis and serum immuno-fixation electrophoresis (IFE) might find no anomalies even if the bone marrow (BM) examination is performed. Thus, it is easy to miss the diagnosis. CASE SUMMARY: A 62-year-old man diagnosed as IgD-λ/λ myeloma (ISS stage III) was admitted with fatigue and weight loss. The physical examination suggested an anemic face, a few moist rales at the left lung base, and mild concave edema in both lower extremities. Laboratory examinations showed the elevated creatinine levels, ß2-microglobulin, lactic dehydrogenase, and erythrocyte sedimentation rate, while the decreased neutrophils, granulocytes, and hemoglobin. In the serum protein electrophoresis, there appeared two inconspicuous M-spikes. Serum IFE indicated an over-representation of lambda light chain and yielded two monoclonal bands in λ region, but only one corresponding heavy chain band in the antisera to IgD region. The BM histology and BM cytology both supported the diagnosis of IgD-λ/λ myeloma. CONCLUSION: This case highlights the differential clinical manifestations and laboratory findings of IgD-λ/λ myeloma to help minimize the chance of misdiagnosis.

6.
Sci Total Environ ; 707: 136105, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31874393

RESUMO

Alkaline pretreatment was demonstrated to be effective in the enhancement of hydrogen production. However, the sludge solubilization rate of alkaline pretreatment is still limited. This study reports a new strategy of K2FeO4 + pH 9.5 for sludge mesophilic anaerobic fermentation. Experimental results showed that the combination of K2FeO4/pH 9.5 pretreatment had a greater hydrogen yield than the individual K2FeO4 and pH 9.5. The maximum hydrogen yield was 19.2 mL per gram volatile suspended solids (VSS) under the optimal condition (0.02 g per gram total suspended solids K2FeO4 + pH 9.5). Kinetic analysis showed that the highest hydrogen production potential of 19.9 mL/g VSS was obtained in the combined reactor, which well fitted the first-order kinetic model (R2 = 0.9925). Besides, the fermentation type was mainly acetic and butyric in the combined reactor, which contributed to hydrogen production. Further analyses showed that the combined pretreatment reduced hydrogen sulfide yield, providing an environmentally friendly method to sludge treatment.


Assuntos
Reatores Biológicos , Esgotos , Fermentação , Hidrogênio , Concentração de Íons de Hidrogênio , Compostos de Ferro , Cinética , Compostos de Potássio
7.
Nanoscale ; 11(45): 21782-21789, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31709434

RESUMO

For efficient cancer vaccines, the antitumor function largely relies on cytotoxic T cells, whose activation can be effectively induced via antigen-encoding mRNA, making mRNA-based cancer vaccines an attractive approach for personalized cancer therapy. While the liposome-based delivery system enables the systemic delivery and transfection of mRNA, incorporating an adjuvant that is non-lipid like remains challenging, although the co-delivery of mRNA (antigen) and effective adjuvant is key to the activation of the cytotoxic T cells. This is because the presence of an adjuvant is important for dendritic cell maturation-another necessity for cytotoxic T cell activation. In the present work, we designed a poly (lactic-co-glycolic acid) (PLGA)-core/lipid-shell hybrid nanoparticle carrier for the co-delivery of mRNA and gardiquimod (adjuvant that cannot be incorporated into the lipid shell). We demonstrated in the present work that the co-delivery of mRNA and gardiquimod led to the effective antigen expression and DC maturation in vitro. The intravenous administration of the hybrid nanovaccine resulted in the enrichment of mRNA expression in the spleen and a strong immune response in vivo. The simultaneous delivery of the antigen and adjuvant both spatially and temporally via the core/shell nanoparticle carrier is found to be beneficial for tumor growth inhibition.


Assuntos
Adjuvantes Imunológicos , Aminoquinolinas , Vacinas Anticâncer , Imidazóis , Nanopartículas , Neoplasias Experimentais , RNA Neoplásico , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacocinética , Adjuvantes Imunológicos/farmacologia , Aminoquinolinas/química , Aminoquinolinas/farmacocinética , Aminoquinolinas/farmacologia , Animais , Apresentação de Antígeno/efeitos dos fármacos , Apresentação de Antígeno/imunologia , Vacinas Anticâncer/química , Vacinas Anticâncer/farmacocinética , Vacinas Anticâncer/farmacologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Células Dendríticas/patologia , Imidazóis/química , Imidazóis/farmacocinética , Imidazóis/farmacologia , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacocinética , Ácido Poliglicólico/farmacologia , RNA Neoplásico/química , RNA Neoplásico/farmacocinética , RNA Neoplásico/farmacologia , Linfócitos T Citotóxicos/imunologia
8.
Nanoscale ; 10(32): 15332-15338, 2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30070282

RESUMO

Real time monitoring of drug release at specific local sites by a non-invasive imaging method is critical in patient-specific drug administration in order to avoid insufficient or excess drug dosing. In the present work, we designed a specific carrier system for such a purpose using self-decomposable SiO2 nanoparticles (NPs) with the drug being loaded in the center and Au NPs on the SiO2 NPs as the imaging agent. We discovered a correlation between the drug release from the carrier and the morphological evolution of Au NPs, which also left the carrier and changed their aggregation states along with the drug release process. This finding enabled the real time monitoring of the drug release at local sites (e.g. tumor) in a quantitative manner by recording the CT signal evolution of the Au NPs, as demonstrated in vivo using mice bearing Colo-205 xenografts. The present work provided a promising platform for non-invasive real time tracking on the localized drug release, enabling a variety of personalized therapeutic applications.


Assuntos
Portadores de Fármacos , Liberação Controlada de Fármacos , Ouro , Nanopartículas Metálicas , Dióxido de Silício , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Nus , Neoplasias , Ensaios Antitumorais Modelo de Xenoenxerto
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