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1.
J Environ Manage ; 360: 121161, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761626

RESUMO

Recent attention on the detrimental effects of pharmaceutically active compounds (PhACs) in natural water has spurred researchers to develop advanced wastewater treatment methods. Carbamazepine (CBZ), a widely recognized anticonvulsant, has often been a primary focus in numerous studies due to its prevalence and resistance to breaking down. This study aims to explore the effectiveness of a bio-electrochemical system in breaking down CBZ in polluted water and to assess the potential harmful effects of the treated wastewater. The results revealed bio-electro degradation process demonstrated a collaborative effect, achieving the highest CBZ degradation compared to electrodegradation and biodegradation techniques. Notably, a maximum CBZ degradation efficiency of 92.01% was attained using the bio-electrochemical system under specific conditions: Initial CBZ concentration of 60 mg/L, pH level at 7, 0.5% (v/v) inoculum dose, and an applied potential of 10 mV. The degradation pathway established by identifying intermediate products via High-Performance Liquid Chromatography-Mass Spectrometry, revealed the complete breakdown of CBZ without any toxic intermediates or end products. This finding was further validated through in vitro and in vivo toxicity assays, confirming the absence of harmful remnants after the degradation process.


Assuntos
Biodegradação Ambiental , Carbamazepina , Poluentes Químicos da Água , Carbamazepina/toxicidade , Poluentes Químicos da Água/toxicidade , Águas Residuárias/química , Animais
2.
Int Microbiol ; 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37659056

RESUMO

Bisphenol A (BpA) is an endocrine-disrupting substance commonly found in plastics and resins. It is reported that BpA exposure induces lipid accumulation in humans, similar to obesogenic compounds. The main objective of this study is to investigate the removal of BpA using Lactiplantibacillus sp. D10-2, and to examine its potential for reducing BpA-induced lipid accumulation in 3T3-L1 cell line model. The heat-dried cells of Lactiplantibacillus sp. D10-2 showed 69.7% removal efficiency for initial BpA concentration of 10 µg/mL, which was 30.5% higher than the live cells. The absence of metabolites or intermediates in BpA removal studies indicates that the Lactiplantibacillus sp. D10-2 strain removed BpA by adsorption process. The hydrophobic interactions of heat-dried Lactiplantibacillus sp. D10-2 cells were observed to be higher with 33.7% compared to live cells (15.0%), suggesting a stronger ability to bind with BpA. Although the BpA binding onto Lactiplantibacillus sp. D10-2 was not affected by pH, it was confirmed that as the temperature increases, the binding ability got decreased due to mass transfer and diffusion of BpA molecules. Treatment with Lactiplantibacillus sp. D10-2 (0.1, 0.25, 0.5, 1%) reduced lipid accumulation by 61.7, 58.0, 52.7 and 60.4% in 3T3-L1 cells exposed with BpA. In addition, it was confirmed that Lactiplantibacillus sp. D10-2 treatment suppressed the protein expression levels of lipogenesis-related PPARγ and C/EBPα in 3T3-L1 cells. The results of the study suggest that the Lactiplantibacillus sp. D10-2 strain can remove BpA and reduce BpA-accelerated lipid accumulation in 3T3-L1 cells.

3.
J Appl Microbiol ; 134(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37989872

RESUMO

AIM: To assess the effectiveness of Lentilactobacillus parafarraginis A6-2 cell lysate for the removal of aluminum (Al), which induces neurotoxicity, and its protective effect at cellular level. METHODS AND RESULTS: The cell lysate of the selected L. parafarraginis A6-2 strain demonstrated superior Al removal compared to live or dead cells. The Al removal efficiency of L. parafarraginis A6-2 cell lysate increased with decreasing pH and increasing temperature, primarily through adsorption onto peptidoglycan. Neurotoxicity mitigation potential of L. parafarraginis A6-2 was evaluated using C6 glioma cells. C6 cells exposed with increasing concentration of Al led to elevated toxicity and inflammation, which were gradually alleviated upon treatment with L. parafarraginis A6-2. Moreover, Al-induced oxidative stress in C6 cells showed a concentration-dependent reduction upon treatment with L. parafarraginis A6-2. CONCLUSIONS: This study demonstrated that L. parafarraginis A6-2 strain, particularly in its lysate form, exhibited enhanced capability for Al removal. Furthermore, it effectively mitigated Al-induced toxicity, inflammation, and oxidative stress.


Assuntos
Alumínio , Estresse Oxidativo , Humanos , Alumínio/toxicidade , Inflamação , Anti-Inflamatórios/farmacologia
4.
Sensors (Basel) ; 23(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37960409

RESUMO

Interfacial tension varies with temperature. This paper investigates the effects of temperature-dependent interfacial tension on shear wave velocity. We designed a nylon cell equipped with bender elements in a cross-hole configuration to measure the shear wave velocity of nine sand-silt mixtures with different degrees of saturation (S = 0%, 2.5%, 5%, 10%, and 100%). All specimens were subjected to a temperature change from 10 °C to 1 °C. The results demonstrate that shear wave velocity tends to be very sensitive to changes in temperature at a low degree of saturation. Particle-scale analyses overlapped with the experimental results and captured the critical role of temperature-dependent interfacial tension in small-strain skeletal stiffness. In fact, the temperature should be considered during laboratory and field shear modulus measurements of the long-term performance of energy geosystems subjected to thermally induced repetitive loads.

5.
Sensors (Basel) ; 21(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917596

RESUMO

The major and minor components in granular soil materials determine their properties and behavior. This study explores the transitional behavior within threshold fines fraction of soil mixtures based on the data from the literature and experiments. From the literature survey, the void ratio, shear wave velocity, compression index, and friction angle capture the transitional turning point between the low and data-adjusted high threshold fines fractions. In particular, there is a dramatic change in hydraulic conductivity below the low threshold fines fraction that highlights the critical role of small amounts of fines in the fluid flow (e.g., clogging). From an experimental study, the engineering properties of natural soil samples identified using deformation and elastic wave sensors show transitional trends within the Revised Soil Classification System framework. The evolution of compressibility and shear wave velocity indicate that either coarse, fine, or both particles are likely to contribute to large and small strain stiffnesses when the effective stress is below 400 kPa. Thereafter, both engineering properties indicate that the soil sample retains a memory of in-situ overburden pressure when the effective stress is around 400 kPa. There is a critical role of fines that are slightly higher than low threshold fines fraction on engineering properties that promote the application of Revised Soil Classification System RSCS to natural soils.

6.
Sensors (Basel) ; 21(9)2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33923238

RESUMO

Freeze-thaw cycles caused by seasonal temperature fluctuations significantly affect the geotechnical engineering properties. This study investigated the crucial role of water distribution patterns in the characterization of elastic wave properties for the fine F-110 sand during a freeze-thaw cycle. Sand specimens with four different water distribution patterns were prepared, namely homogeneously-mixed, evaporation-driven, vertically-, and horizontally-layered specimens. The P- and S-wave signatures of the specimens were monitored using piezo crystal sensors. Results indicated the criticality of water distribution patterns in the determination of small-strain soil properties even though the specimens had identical global water saturation. The nuclear magnetic resonance-based water volume depth profiles indicated that the evaporation-driven specimens had more heterogeneous pore-invasive ice-bonding layers at a high water saturation region; by contrast, the drying process facilitated uniform meniscuses around the particle contacts near the air percolation threshold. Elastic wave measurements for laboratory-prepared specimens might over/underestimate the small-strain soil stiffness of sediments in nature, wherein the drying processes prevailed to control the water saturation. This study highlighted a clear transition from capillary-controlled to cementation-controlled elastic wave properties during temperature oscillations.

7.
J Pept Sci ; 26(3): e3237, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31852026

RESUMO

Delivering biomolecules, such as antibodies, proteins, and peptides, to the cytosol is an important and challenging aspect of drug development and chemical biology. Polyarginine-a well-known cell-penetrating peptide (CPP)-is capable of exploiting its positive charge and guanidium groups to carry a fused cargo into the cytosol. However, the precise mechanism by which this occurs remains ambiguous. In the present study, we established a new method of quantitatively assessing cell penetration. The method involves inducing cell death by using a polyarginine (R8) to deliver a peptide-ie, mitochondrial targeting domain (MTD)-to the cytosol. We found that 4,4'-diisothiocyanatostilbene-2,2'-di-sulfonate (DIDS)-an anion channel blocker-inhibited the ability of octa-arginine (R8)-fused MTD to penetrate cells. Other anion channel blockers did not inhibit the penetration of peptides fused with R8. Comparison of DIDS with other structurally similar chemicals revealed that the isothiocyanate group of DIDS may be primarily responsible for the inhibitory effect than its stilbene di-sulfonate backbone. These results imply that the inhibitory effect of DIDS may not be derived from the interaction between stilbene di-sulfonate and the anion channels, but from the interaction between the isothiocyanate groups and the cell membrane. Our new MTD method enables the quantitative assessment of cell penetration. Moreover, further studies on the inhibition of CPPs by DIDS may help clarify the mechanism by which penetration occurs and facilitate the design of new penetrative biomolecules.


Assuntos
Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/efeitos adversos , Peptídeos Penetradores de Células/farmacologia , Oligopeptídeos/química , Proteínas Proto-Oncogênicas c-bcl-2/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/química , Interações Medicamentosas , Células HeLa , Humanos , Camundongos , Domínios Proteicos
8.
Biochem Biophys Res Commun ; 518(1): 80-86, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31421829

RESUMO

Noxa is a weak apoptosis activator consisting of a BH3 domain and a mitochondrial-targeting domain (MTD). BH3 binds Mcl-1 and Bcl2A1 and inactivates their anti-apoptotic activities, while MTD delivers BH3 to mitochondria. Previously we revealed that MTD may also function as an inducer of necrosis via conjugation with octa-arginine, which induces cytosolic Ca2+ influx from mitochondria. However, the mechanism(s) underlying this process has not been elucidated yet. Here, we show that calcium influx induced by an MTD peptide fused with octa-arginine residue (R8:MTD) originates not only from mitochondria but also from the extracellular space. However, calcium spikes were not sufficient for necrosis. R8:MTD induced mitochondrial permeability transition pore opening, fragmentation, and swelling. These mitochondrial events induced by MTD appeared to be necessary for necrosis induction, since DIDS, a VDAC inhibitor, inhibited the mitochondrial swelling and cell death induced by MTD. We show that R8:MTD disrupted endoplasmic reticulum (ER) structures but not peroxisomes or Golgi, indicating that R8:MTD causes necrosis by inducing ER events as well.


Assuntos
Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/química , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Cálcio/metabolismo , Morte Celular/efeitos dos fármacos , Citosol/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Espaço Extracelular/metabolismo , Células HeLa , Humanos , Mitocôndrias/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Dilatação Mitocondrial/efeitos dos fármacos , Peptídeos/química , Domínios Proteicos , Canais de Ânion Dependentes de Voltagem/antagonistas & inibidores , Canais de Ânion Dependentes de Voltagem/metabolismo
9.
Biochem Biophys Res Commun ; 495(2): 1661-1667, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29222049

RESUMO

The mitochondrial targeting domain (MTD) of Noxa has necrosis-inducing activity when conjugated with cell-penetrating peptide (CPP). In this study, we report another MTD-like motif, B1MLM, found in BNIP1, a pro-apoptotic BH3-only protein found in the endoplasmic reticulum membrane. The B1MLM peptide, conjugated with CPP, induced necrosis in a way similar to that of R8:MTD. R8:B1MLM caused an intracellular calcium spike, mitochondrial reactive oxygen species generation, and mitochondrial fragmentation. The cytosolic calcium spike was likely due to the opening of the mitochondrial permeability transition pore.


Assuntos
Sinalização do Cálcio , Proteínas Proto-Oncogênicas c-bcl-2/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/metabolismo , Células HeLa , Humanos , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Necrose , Proteínas Proto-Oncogênicas c-bcl-2/genética , Espécies Reativas de Oxigênio/metabolismo
10.
Amino Acids ; 50(12): 1707-1717, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30196335

RESUMO

The resistance of tumor cells to apoptosis-inducing anticancer agents is regarded as a major impediment for the treatment of cancer patients. This study aimed to examine the possibility whether a necrosis-inducing peptide containing the mitochondria-targeting domain (MTD) of NOXA kills tumor cells that are resistant to apoptosis-inducing anticancer agents. To examine this possibility, we established doxorubicin-resistant (Dox-Res) cells by treating CT26 cells with increasing amounts of doxorubicin. The apoptosis resistance of the Dox-Res CT26 cells was confirmed by measuring the cell viability and activation of caspases. We showed that the MTD-containing peptide fused to eight arginine residues (R8:MTD), a necrosis-inducing peptide, induced necrosis in the Dox-Res CT26 cells, together with a cytosolic calcium spike, reactive oxygen species production, and the release of high mobility group box 1 into the media. Moreover, we demonstrated the killing effect of R8:MTD in tumor tissues generated using the Dox-Res CT26 cells in a mouse model. Therefore, our results suggest that MTD-containing peptides may provide an alternative tool for the elimination of relapsed tumor cells that are not responsive to apoptosis-inducing anticancer agents.


Assuntos
Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Humanos , Camundongos Endogâmicos BALB C , Necrose , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/química , Espécies Reativas de Oxigênio/metabolismo
11.
Arch Microbiol ; 198(8): 737-42, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27154571

RESUMO

Phytoremediation is an in situ, low-cost strategy for cleanup of the sites contaminated with heavy metals. Experiments were conducted to assess the impact of synthetic chelators and plant growth-promoting rhizosphere bacteria (Herbaspirillum sp. GW103) on heavy metal lead (Pb) uptake in Z. mays cultivated in Pb-contaminated soil. The present study investigated the Pb phytoaccumulation rate and plant antioxidant enzyme activities in Z. mays exposed to 100 mg/kg of PbNO3. The combination of gluconic acid (GA) with Herbaspirillum sp. GW103 treatment showed higher Pb solubility (18.9 mg/kg) compared with other chelators. The chemical chelators showed the significant difference in phytoaccumulation as well as antioxidant enzyme activities. The antioxidant enzymes such as catalase, peroxidase and superoxide dismutase activities changed under Pb stress. The study indicated that increased activity of antioxidant enzymes may play as signal inducers to fight against Pb.


Assuntos
Antioxidantes/metabolismo , Quelantes/metabolismo , Herbaspirillum/metabolismo , Chumbo/metabolismo , Nitratos/metabolismo , Poluentes do Solo/metabolismo , Zea mays/metabolismo , Biodegradação Ambiental , Catalase/metabolismo , Gluconatos/metabolismo , Herbaspirillum/enzimologia , Estresse Oxidativo/fisiologia , Peroxidases/metabolismo , Rizosfera , Superóxido Dismutase/metabolismo , Zea mays/microbiologia
12.
Microbiol Immunol ; 60(5): 343-55, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26989992

RESUMO

In traditional Asian medicine, Aralia cordata (AC) is a known as a pain reliever and anti-inflammatory drug. Although several of its biological activities have been reported, the immunomodulatory effects of a hot water extract of AC (HAC) have not yet been described. The aim of this study was to investigate whether HAC modulates the activation of macrophages, which play important roles in innate immune responses against microbial pathogens, and if so, to determine the molecular mechanisms by which HAC mediates this process. It was found that HAC activates bone marrow-derived macrophages (BMDM) and increases amounts of nitric oxide and proinflammatory cytokines in a dose-dependent manner. In addition, HAC was found to induce phosphorylation of NF-κB and mitogen-activated protein kinases (MAPKs), including c-Jun N-terminal kinases, extracellular signal-regulated kinases and p38. Interestingly, these effects were absent in BMDM prepared from myeloid differentiation protein 88-knockout mice. Polysaccharides from HAC exerted stronger immunostimulatory effects than HAC itself. Furthermore, orally administered HAC clearly enhanced clearance of the intracellular pathogen Listeria monocytogenes by boosting innate immune responses. These results demonstrate that HAC exerts immunostimulatory effects through the TLR/MyD88 and NF-κB/MAPK signal transduction pathways.


Assuntos
Aralia/química , Fatores Imunológicos/farmacologia , Listeriose/prevenção & controle , Macrófagos/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Extratos Vegetais/farmacologia , Animais , Imunidade Inata , Fatores Imunológicos/isolamento & purificação , Listeria monocytogenes/imunologia , Listeriose/imunologia , Macrófagos/efeitos dos fármacos , Camundongos Knockout , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 88 de Diferenciação Mieloide/deficiência , NF-kappa B/metabolismo , Fosforilação , Extratos Vegetais/isolamento & purificação , Processamento de Proteína Pós-Traducional
13.
Curr Microbiol ; 71(3): 311-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26048485

RESUMO

This study investigated the expression rate and molecular modeling of Wzb gene, a low molecular weight protein tyrosine phosphatase, under As stress in Herbaspirillum sp. GW103. Expression of Wzb gene was quantified at transcriptional level through real-time quantitative PCR. The results showed up- and down-regulations of Wzb gene in the presence of As (50 and 100 mg/L). The maximum Wzb transcript expression was 1.2-fold after 72 h exposure to 50 mg/L of As. However, the minimum expression was 0.1-fold after 48 h exposure to 100 mg/L of As. The Wzb protein sequence was retrieved from NCBI sequence database and was used for in silico analysis. 3D structure of Wzb gene was predicted by comparative modeling using modeler 9v9. Further, the model was validated for its quality by Ramachandran plot, ERRAT, Verify 3D, and SAVES server which revealed structure and quality of the Wzb gene model.


Assuntos
Arsênio/toxicidade , Perfilação da Expressão Gênica , Herbaspirillum/efeitos dos fármacos , Herbaspirillum/enzimologia , Proteínas Tirosina Fosfatases/biossíntese , Proteínas Tirosina Fosfatases/química , Modelos Moleculares , Conformação Proteica , Proteínas Tirosina Fosfatases/genética , Reação em Cadeia da Polimerase em Tempo Real , Transcrição Gênica
15.
Appl Microbiol Biotechnol ; 98(19): 8179-89, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25073519

RESUMO

We present a simple, eco-friendly synthesis of silver and gold nanoparticles using a natural polymer pine gum solution as the reducing and capping agent. The pine gum solution was combined with silver nitrate (AgNO3) or a chloroauric acid (HAuCl4) solution to produce silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs), respectively. The reaction process was simple; formation of the nanoparticles was achieved by autoclaving the silver and gold ions with the pine gum. UV-Vis spectra showed surface plasmon resonance (SPR) for silver and gold nanoparticles at 432 and 539 nm, respectively. The elemental forms of AgNPs and AuNPs were confirmed by energy-dispersive X-ray spectroscopy (EDX). Fourier transform infrared spectroscopy (FTIR) showed the biomolecules present in the pine gum, AgNPs, and AuNPs. Transmission electron microscopy (TEM) images showed the shape and size of AgNPs and AuNPs. The crystalline nature of synthesized AgNPs and AuNPs was confirmed by X-ray crystallography [X-ray diffraction (XRD)]. Application of synthesized AgNPs onto cotton fabrics and leather, in order to evaluate their antibacterial properties against odor- or skin infection-causing bacteria, is also discussed. Among the four tested bacteria, AgNP-coated cotton fabric and leather samples displayed excellent antibacterial activity against Brevibacterium linens.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Nanopartículas Metálicas/química , Odorantes/prevenção & controle , Prata/farmacologia , Dermatopatias Bacterianas/veterinária , Têxteis/microbiologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Odorantes/análise , Prata/química , Pele/microbiologia , Dermatopatias Bacterianas/microbiologia , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Têxteis/análise
16.
Bioprocess Biosyst Eng ; 37(10): 1935-43, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24668029

RESUMO

In the present study, we synthesized silver and gold nanoparticles with a particle size of 10-20 nm, using Zingiber officinale root extract as a reducing and capping agent. Chloroauric acid (HAuCl4) and silver nitrate (AgNO3) were mixed with Z. officinale root extract for the production of silver (AgNPs) and gold nanoparticles (AuNPs). The surface plasmon absorbance spectra of AgNPs and AuNPs were observed at 436-531 nm, respectively. Optimum nanoparticle production was achieved at pH 8 and 9, 1 mM metal ion, a reaction temperature 50 °C and reaction time of 150-180 min for AgNPs and AuNPs, respectively. An energy-dispersive X-ray spectroscopy (SEM-EDS) study provides proof for the purity of AgNPs and AuNPs. Transmission electron microscopy images show the diameter of well-dispersed AgNPs (10-20 nm) and AuNPs (5-20 nm). The nanocrystalline phase of Ag and Au with FCC crystal structures have been confirmed by X-ray diffraction analysis. Fourier transform infrared spectroscopy analysis shows the respective peaks for the potential biomolecules in the ginger rhizome extract, which are responsible for the reduction in metal ions and synthesized AgNPs and AuNPs. In addition, the synthesized AgNPs showed a moderate antibacterial activity against bacterial food pathogens.


Assuntos
Antibacterianos/química , Ouro/química , Nanopartículas Metálicas , Extratos Vegetais/química , Raízes de Plantas/química , Prata/química , Zingiber officinale/química , Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Listeria/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Extratos Vegetais/farmacologia , Espectrometria por Raios X , Staphylococcus/efeitos dos fármacos , Ressonância de Plasmônio de Superfície
17.
Indian J Microbiol ; 54(2): 196-202, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25320422

RESUMO

This study reveals a green process for the production of multi-morphological silver (Ag NPs) and gold (Au NPs) nanoparticles, synthesized using an agro-industrial residue cashew nut shell liquid. Aqueous solutions of Ag(+) ions for silver and chloroaurate ions for gold were treated with cashew nut shell extract for the formation of Ag and Au NPs. The nano metallic dispersions were characterized by measuring the surface plasmon absorbance at 440 and 546 nm for Ag and Au NPs. Transmission electron microscopy showed the formation of nanoparticles in the range of 5-20 nm for silver and gold with assorted morphologies such as round, triangular, spherical and irregular. Scanning electron microscopy with energy dispersive spectroscopy and X-ray diffraction analyses of the freeze-dried powder confirmed the formation of metallic Ag and Au NPs in crystalline form. Further analysis by Fourier transform infrared spectroscopy provided evidence for the presence of various biomolecules, which might be responsible for the reduction of silver and gold ions. The obtained Ag and Au NPs had significant antibacterial activity, minimum inhibitory concentration and minimum bactericidal concentration on bacteria associated with fish diseases.

18.
Sci Rep ; 14(1): 11453, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769161

RESUMO

Stratified water columns are often found in lakes and oceans. Stratifications result from differences in density due to salt concentration, temperature, solid content and oxygenation. The stability of stratifications affects bioactivity, sedimentation, contaminant transport and environmental remediation. This study investigates the evolution of 6 stratified water columns created by differences in salinity, suspended minerals and the presence of a bottom heat source. We use acoustic wave reflection, photography, and both electrical conductivity and temperature profiles to track changes in stratification. Results show that multiple concurrent processes emerge across layers in otherwise quiescent water bodies. Dissimilar chemo-thermo conditions give rise to chemical and thermal diffusion, convection, and double-diffusion convection. When stratification involves suspended particles, interlayer processes include diffusiophoresis, flocculation/aggregation, sedimentation, osmosis, and chemo-consolidation; in this case, the specific surface and surface charge of suspended particles, and the salt concentration in contiguous layers determine aggregation-sedimentation-consolidation patterns. The interlayer transition zone acts as a high-pass filter that preferentially reflects low-frequency long-wavelength P-waves; invasive thermal and electrical conductivity probes provide complementary information and may identify stratification even when it is undetected by acoustic signals.

19.
Mol Cells ; 47(6): 100075, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38823606

RESUMO

Excessive blood vessel wall thickening, known as intimal hyperplasia, can result from injury or inflammation and increase the risk of vascular diseases. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) plays key roles in tumor surveillance, autoimmune diseases, and apoptosis; however, its role in vascular stenosis remains controversial. Treatment with recombinant isoleucine zipper hexamerization domain soluble TRAIL (ILz(6):TRAIL) significantly inhibited the progression of neointimal hyperplasia (NH) induced by anastomosis of the carotid artery and jugular vein dose dependently, and adenovirus expressing secretable ILz(6):TRAIL also inhibited NH induced by balloon injury in the femoral artery of rats. This study demonstrated the preventive and partial regressive effects of ILz(6):TRAIL on anastomosis of the carotid artery and jugular vein- or balloon-induced NH.


Assuntos
Hiperplasia , Neointima , Ratos Sprague-Dawley , Ligante Indutor de Apoptose Relacionado a TNF , Animais , Neointima/patologia , Neointima/prevenção & controle , Ratos , Masculino , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Artérias Carótidas/patologia , Artérias Carótidas/cirurgia , Veias Jugulares/patologia , Artéria Femoral/lesões , Artéria Femoral/patologia , Artéria Femoral/cirurgia
20.
Chemosphere ; 361: 142554, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38851502

RESUMO

Increasing multidrug-resistant pathogenic microbial around the world become a global problem, making it imperative to develop effective methods for bacterial inactivation in wastewater. In this study, we propose a multifunctional photoelectrochemical (PEC) system to successfully disinfect microbial cells and degrade orange (II) dyes. CoOx NP were synthesized by spin-coating onto hydrothermally synthesized TiO2 nanorod arrays followed by electrodeposited NiFe-LDH to develop the NiFe-LDH/CoOx NP-TiO2 NRs. Interestingly, spin-coated CoOx NP-TiO2 NRs exhibited a 1.5-fold enhancement in photocurrent (1.384 mA/cm2) than pristine TiO2 NRs (0.92 mA/cm2). A NiFe-layered double hydroxide (LDH) cocatalysts layer further exhibits the maximum photocurrent density of 1.64 mA/cm2 with IPCE of 84.5% at 1.0 VAg/AgCl at 380 nm. Furthermore, NiFe-LDH/CoOx-TiO2 NR photoanodes were effectually employed for photoelectrochemical bacteria disinfection and organic pollutant removals. With NiFe-LDH/CoOx-TiO2 NR, 99% (120 min) bacterial inactivation and 99% (60 min) orange II dye decomposition efficiency was achieved. Superoxide radicals (-O2•), hydroxyl radicals (HO•), and holes (h+) played a critical role in the PEC degradation systems. Due to the synergy between NiFe-LDH cocatalyst and CoOx interlayer, surface water oxidation reactions were accelerated over NiFe-LDH/CoOx NP-TiO2 NRs. The charge transport process in NiFe-LDH/CoOx NP-TiO2 NRs photoanode-based PEC system was proposed in detail.


Assuntos
Eletrodos , Titânio , Águas Residuárias , Titânio/química , Águas Residuárias/química , Catálise , Técnicas Eletroquímicas/métodos , Poluentes Químicos da Água/química , Hidróxidos/química , Eliminação de Resíduos Líquidos/métodos , Processos Fotoquímicos , Nanotubos/química , Corantes/química , Compostos Azo/química , Purificação da Água/métodos , Desinfecção/métodos
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