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1.
J Colloid Interface Sci ; 666: 585-593, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38613980

RESUMO

Capacitive deionization (CDI) is flourishing as an energy-efficient and cost-effective water desalination method. However, challenges such as electrode degradation and fouling have hindered the practical deployment of CDI technology. To address these challenges, the key point of our strategy is applying a hydrophilic coating composed of polyethylene glycol (PEG)-functionalized nano-TiO2/polyvinylidene fluoride (PVDF) to the electrode interface (labeled as APPT electrode). The PEG/PVDF/TiO2 layer not only mitigates the co-ion depletion, but also imparts the activated carbon (AC) electrode hydrophilicity. As anticipated, the APPT electrode possessed an enhanced desalination capacity of 83.54 µmol g-1 and a low energy consumption of 17.99 Wh m-3 in 10 mM sodium chloride solution compared with the bare AC electrode. Notably, the APPT maintained about 93.19 % of its desalination capacity after 50 consecutive adsorption-desorption cycles in the presence of bovine serum albumin (BSA). During the trial, moreover, no obvious overall performance decline was noted in concentration reduction (Δc), water recovery (WR) and productivity (P) over 50 cycles. This strategy realizes energy-efficient, antifouling and stable brackish water desalination and has great promise for practical applications.

2.
Chemosphere ; 353: 141358, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311042

RESUMO

An electrochemical membrane filtration system provides an innovative approach to enhance contaminant removal and mitigate membrane fouling. There is an urgent need to develop portable, versatile, and efficient electrochemical membranes for affordable wastewater treatment. Here, a 3D conductive gradient fiber membrane (CC/PVDF) with a gradient porous structure was prepared using a two-step phase inversion method. Methyl orange (MO) was utilized as model organic substance to investigate the electrochemical performance of the CC/PVDF membrane. At applied potentials of +2 V, +3 V, -2 V and -3 V, the removal efficiency of MO was 5.1, 5.3, 4.8, and 5.1 times higher than at 0 V. A dramatic flux loss of 35.02% occurred on the membrane without electrochemistry, interestingly, whereas the flux losses were only 23.59%-10.24% in the applied potential after 30 min of filtration, which were approximately 1.18, 1.28, 1.29 and 1.38 times as high as that without electrochemistry, respectively. The enhanced removal and anti-fouling performances of the membranes were attributed to the functions of electrochemical degradation, electrostatic repulsion, and electrically enhanced wettability. Electrochemical generation of Hydrogen peroxide, along with HO• radicals, was detected and direct electron transfer and HO• were proved to be the dominant oxidants responsible for MO degradation. The intermediate oxidation products were identified by mass spectrometry, and an electrochemical degradation pathway of MO was proposed based on bond-breaking oxidation, ring-opening reactions, and complete oxidation. All the findings emphasize that the ECMF system possesses superior efficiency and creative potential for water purification applications.


Assuntos
Polímeros de Fluorcarboneto , Membranas Artificiais , Polivinil , Purificação da Água , Eletricidade , Condutividade Elétrica , Eletricidade Estática , Purificação da Água/métodos
3.
Chemosphere ; 314: 137545, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36526138

RESUMO

Membrane fouling and the trade-off between membrane permeability and selectivity restrict the potential applications of membrane filtration for water treatment. ZIF-8 was found having great permeability and antibiofouling performance, but with issue on particle aggregation makes it difficult to achieve high ZIFs loading and fabricate a defect-free molecular sieving membrane in previous research. In this study, we formed a scalable antibiofouling surface with improved permeability and fouling resistance on a PEI-ZIF-PAA membrane using a layer-by-layer assembly technique. The synergistic effects of being sandwiched between two different polyelectrolyte layers with opposite charges endowed the ZIF nanoparticles with improved stability and scalability for membrane modification. The PEI-ZIF-PAA membrane exhibited a satisfactory water flux of 120.78 LMH, which was 46.97% higher than that of the pristine PES membrane. The normalized water flux loss was serious in the absence of ZIF-8, and the flux increased with the ZIF-8 concentration. Antifouling tests suggested that the PEI-ZIF-PAA membrane possessed good antifouling performance due to the much higher surface hydrophilicity and positive Lewis acid-base interactions with foulants. The HA rejection increased with the ZIF-8 concentration and reached a maximum of 92.1% in the presence of 1.00% (w/v) ZIF-8. The membrane regeneration was tested under physical and chemical cleaning with flux recovery rates of about 85% and 95%. XDLVO analysis showed that the total interaction energy between HA and the PEI-ZIF-8-PAA membrane was 26.45 mJ/m2, and the superior antifouling performance was mainly attributed to Lewis acid-base interactions. This study indicates that ZIF-8 nanocrystals are promising materials for fabricating novel membranes for sewage treatment.


Assuntos
Incrustação Biológica , Incrustação Biológica/prevenção & controle , Ácidos de Lewis , Membranas Artificiais , Filtração , Interações Hidrofóbicas e Hidrofílicas
4.
J Hazard Mater ; 434: 128879, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427970

RESUMO

Pharmaceuticals are necessary to be removed from environment. Herein TiO2 incorporated biochar made from pyrolysis of agricultural wastes was encapsulated into chitosan to obtain a novel hydrogel beads. This hydrogel beads executed a dual role as both adsorbent and sonocatalyst, which proved to be suitable for the removal of antibiotic ciprofloxacin (CIP) from water. The results showed that adsorption of CIP followed pseudo first order kinetics model and Langmuir adsorption isotherm model, having maximum adsorption at pH 9. Whereas the degradation was more efficient at pH 6 due to greater standard potential for •OH/H2O in acidic media. The degradation was maximum at 150 W of ultrasonic power, then decreased in presence of dissimilar electrolytes and even reduced to 0 in presence of Na3PO4. Different quenchers such as benzoquinone (BQ), Triethanolamine (TEA) and isopropyl alcohol (IPA) reduced degradation efficiency (DE) and mineralization efficiency (ME). The DE was decreased from 85.23% to 81.50% (BQ), 74.27% (TEA), and 61.77% (IPA) within 25 min. The prepared sonocatalyst was capable of regeneration with DE, remaining sufficiently high (62%) even after four regeneration steps. These results indicate that titanium-biochar/chitosan hydrogel beads (TBCB) are durable and effective for long-term CIP removal.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Ciprofloxacina , Hidrogéis , Concentração de Íons de Hidrogênio , Cinética , Titânio
5.
J Endod ; 48(6): 749-758, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35219748

RESUMO

INTRODUCTION: Odontoblasts, terminally differentiated dentin-forming cells with their processes that penetrate into dentin, have been considered potential sensory cells. Current research suggests that odontoblasts sense external stimuli and transmit pain signals. PIEZO1, as a specific mechanically activated ion channel, may play an important role in mechanical transduction in odontoblasts. In this study, we devoted to investigating the functions and underlying molecular mechanisms of PIEZO1 ion channels in odontoblast mechanotransduction. METHODS: Human dental pulp stem cells were cultured in vitro and induced to differentiate into odontoblast-like cells (OLCs). The expression of PIEZO1 protein in pulp, dental pulp stem cells, and OLCs was detected by immunohistochemistry or immunofluorescence. The mechanical sensitivity of OLCs was detected by a constructed fluid shear stress model and examined by calcium fluorescence intensity. A single-cell mechanical stimulation model was used to detect the PIEZO1 electrophysiological properties of OLCs. Yoda1 (a PIEZO1-specific agonist), GsMTx4 (a PIEZO1 antagonist), and non-calcium ion extracellular solution were utilized to confirm PIEZO1 mechanotransduction in OLCs in both fluid shear stress and single-cell mechanical stimulation assays. The amount of ATP released by OLCs was measured under stimulation with Yoda1 and GsMTx4. Rat trigeminal ganglion neurons were cultured in vitro and detected by whole-cell patch-clamp recording under ATP stimulation. RESULTS: PIEZO1 ion channels were positively expressed in OLCs and odontoblastic bodies and processes but weakly expressed in dental pulp cells. After the treatment of OLCs with shearing stress or Yoda1, the fluorescence intensity of intracellular calcium ions increased rapidly but did not noticeably change after treatment with GsMTx4 or the non-calcium ion extracellular solution. When single-cell mechanical stimuli were applied to OLCs, the evoked inward currents were recorded by patch-clamp electrophysiology. The inward currents increased and current inactivation became slower after Yoda1 treatment, but these currents almost completely disappeared after the addition of GsMTx4. The amount of ATP released by OLCs increased significantly after Yoda1 stimulation, while GsMTx4 reversed the release of ATP. Whole-cell patch-clamp detection showed that ATP evoked slow inward currents and increased the frequency of action potentials of trigeminal ganglion neurons. CONCLUSIONS: Taken together, these findings indicated that odontoblasts evoked a fast inward current via PIEZO1 ion channels after the application of external mechanical stimuli and released ATP to transmit signals to adjacent cells. Thus, PIEZO1 ion channels in odontoblasts mediate mechanotransduction under various pathophysiological conditions in dentin.


Assuntos
Mecanotransdução Celular , Proteínas de Membrana/metabolismo , Odontoblastos , Trifosfato de Adenosina , Animais , Cálcio/metabolismo , Canais Iônicos/metabolismo , Mecanotransdução Celular/fisiologia , Odontoblastos/metabolismo , Ratos
6.
Chemosphere ; 278: 130341, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33823353

RESUMO

Attractive membranes are critical for improving efficiencies of forward osmosis (FO) desalination process. In this study, a novel FO-PES-MoS2 thin film composite (TFC) membrane was assembled using the phase transfer method through merging MoS2 nanosheets into substrate casting solution. A sequence of characterization techniques was applied to test microstructures and physicochemical properties of the membranes and modification mechanisms based on MoS2 concentrations. Desalination efficiencies of the fabricated membranes were assessed by three NaCl draw solutions. Compared to the blank membrane, the MoS2-contained membranes had a thinner active layer, more upright and open pore structure, higher porosity, and lower surface roughness. 1 wt% MoS2 content was the optimal modification condition, and water flux increased by 35.01% under this condition. Simultaneously, reverse salt flux of the FO-PES-1-MoS2 membrane declined by 29.15% under 1 M NaCl draw solution, indicating increased salt ion rejection performance of the modified membranes. Moreover, Js/Jv ratio indicated that MoS2 nanosheets helped stabilize the desalination performance of the membranes. This study demonstrated that the novel FO-PES-MoS2 TFC membranes possessed improved performances and showed promising properties for saline water desalination.


Assuntos
Membranas Artificiais , Purificação da Água , Osmose , Cloreto de Sódio , Água
7.
Huan Jing Ke Xue ; 42(3): 1093-1104, 2021 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742905

RESUMO

Identifying the quantitative source and hazardous areas of heavy metals in soils plays a pivotal role in soil pollution research, and can provide a basis for regional soil risk monitoring and environmental management. For this purpose, a total of 175 samples were collected in topsoils from Linzi, a typical petrochemical industrial city in Shandong Province. Positive matrix factorization (PMF) and factor analysis with non-negative constraints (FA-NNC) receptor models were applied to analyze the sources of the heavy metals. Based on the multivariate statistical simulation methods of min/max autocorrelation factors (MAF) and sequential Gaussian simulation (SGS), the distribution of heavy metal and potential pollution areas were determined. As, Co, Cr, and Mn were mainly affected by natural sources, their concentrations were dominated by the parent materials, and the high-value areas were distributed in the south of the study area. Hg was the most serious pollution element among the 10 heavy metals analyzed in Linzi and originated from atmosphere deposition from industrial emissions and coal combustion, and the highest values were distributed in the northeast of the study area. Cd, Cu, Ni, Pb, and Zn were dominated by natural sources and human activities. The hot-spot areas were mainly concentrated in the middle of the study area. The potentially contaminated areas of Cd and Hg were 580.80 km2 and 666.60 km2, about 85.04% and 97.59% of the total area, and should require more attention. The potential pollution area of most elements was small and scattered across the study area, accounting for less than 1%.

8.
Environ Toxicol Pharmacol ; 80: 103438, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32569741

RESUMO

Cleft palate is a common congenital maxillofacial malformation in newborns. All-trans retinoic acid (atRA) is an ideal exogenous stimulus to construct a mouse cleft palate model. However, the precise pathogenic mechanism remains to be elucidated. In our study, to explore the toxicity of atRA on palatal shelves during different stages of palate development, a total of 100 mg/kg atRA was administered to C57BL/6 mice at embryonic day 10.5 (E10.5). Mouse embryonic palatal shelves at E13.5, E14.5, E15.5, and E16.5 were collected for RNA extraction and histological treatment. Changes in gene expression were tested through RNA-seq. Selected differentially expressed genes (DEGs) related to metabolic pathways, such as Ptgds, Ttr, Cyp2g1, Ugt2a1 and Mgst3, were validated and analyzed by Quantitative real-time PCR (qRT-PCR). In addition, Gene Oncology analysis showed that transcriptional changes of genes from extracellular matrix (ECM) components, such as Spp1, and crystallin family might play important role in palatal shelves elevation (E13.5-E14.5). Therefore, the protein expression level of Ttr and Spp1 from E13.5 to E16.5 were tested by immunohistochemistry (IHC). Besides, the mRNA level of Spp1, were down-regulated at E16.5 and the protein were down-regulated at E15.5 and E16.5 in all-trans retinoic acid group, suggesting that atRA may involve in palatal bone formation by regulating Spp1. Overall, gene transcriptional profiles were obviously different at each time point of palate development. Thus, this study summarized some pathways and genes that may be related to palatogenesis and cleft palate through RNA-seq, to provide a direction for subsequent studies on the mechanism and targeted therapy of cleft palate.


Assuntos
Fissura Palatina/induzido quimicamente , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Palato/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Transcriptoma/efeitos dos fármacos , Tretinoína/toxicidade , Animais , Fissura Palatina/genética , Feminino , Ontologia Genética , Idade Gestacional , Camundongos , Camundongos Endogâmicos C57BL , Palato/embriologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , RNA/genética , RNA-Seq , Reação em Cadeia da Polimerase em Tempo Real
9.
Environ Sci Pollut Res Int ; 26(16): 16674-16681, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30989603

RESUMO

Nanofiltration polyamide membranes naturally tend towards biofouling, due to their surface physicochemistries. Nisin, a type of short cationic amphiphilic peptide with antimicrobial properties, has been recognized as a safe antimicrobial for food biopreservation and biomedical applications. This study investigates the impact of nisin on the initial bacterial attachment to membranes, its anti-biofouling properties, and characterizes a non-monotonic correlation between nisin concentration and biofilm inhibition. Nisin was found to inhibit B. subtilis (G+) and P. aeruginosa (G-) attachment to both the nanofiltration membrane and the PES membrane. To determine the mechanism of action, we investigated the polysaccharides, protein, and eDNA as target components. We found that the quantities of polysaccharides and eDNA were significantly changed, resulting in bacterial death and anti-adhesion to membrane. However, there were no discernable impacts on protein. We postulated that nisin could prevent irreversible biofouling by decreasing adhesion, killing bacteria, and reducing biofilm formation. We examined membrane flux behavior through bench-scale cross-flow experiments at a set concentration of nisin (100 µg mL-1), with membrane behavior being confirmed using CLSM images. Results showed that nisin could enhance anti-biofouling properties through both anti-adhesive and anti-bacterial effects, and therefore could be a novel strategy against biofouling of membranes.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Membranas Artificiais , Nisina/farmacologia , Bacillus subtilis/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos
10.
J Colloid Interface Sci ; 543: 76-83, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30782519

RESUMO

In this study, humic acid coated biochar (HA-BC) and chitosan were combined to prepare an adsorbent with enhanced reactivity for the removal of ciprofloxacin (CIP). With initial CIP concentrations of 250 mg/L, the maximum adsorbed amount was 154.89 mg/g. Removal rates reached equilibrium after 12 h, obeying the pseudo second-order kinetic model. Adsorption isotherm data was better fitted to the Langmuir isotherm model. The sorption capacity of humic acid-biochar/chitosan hydrogel beads (HBCB) decreased by 11.42%, 6.66%, 9.32%, and 23.92% in the presence of NaCl, NaNO3, Na2SO4, and Na3PO4, respectively. A complex mechanism was found to be responsible for the adsorptive removal of CIP including, hydrogen bonding, π-π electron donor-acceptor (EDA) interactions and hydrophobic interactions. After four regeneration steps, sorption capacity remained sufficient (61.23 mg/g). These removal results indicate that HBCB is durable and effective for long term CIP removal.


Assuntos
Antibacterianos/isolamento & purificação , Ciprofloxacina/isolamento & purificação , Substâncias Húmicas , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Adsorção , Antibacterianos/química , Ciprofloxacina/química , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Propriedades de Superfície
11.
Sci Total Environ ; 639: 560-569, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29800849

RESUMO

Biochar is effective in water treatment but it is hard to retrieve or separate biochar powder from aqueous solutions. In this study, the removal of ciprofloxacin from aqueous solutions was investigated using chitosan/biochar hydrogel beads (CBHB). The results showed that the adsorption rate was almost independent of the temperature and occurred at the homogeneous sites of adsorbent thus obeying the Langmuir model. The equilibrium time was varying for different initial concentrations and found to be 48 h for maximum one. The maximum sorption was found to be >76 mg/g of adsorbent out of 160 mg/L as initial concentration. Adsorption obeyed the second-order mechanism with leading role of intra-particle diffusion and outer diffusion. Adsorption capacity decreased from 34.90 mg/g to 15.77 mg/g in the presence of 0.01 N Na3PO4 whereas other electrolytes such as NaCl, Na2SO4, NaNO3 with same concentration did not affect the sorption capacity. However, increased concentration of NaCl reduced the sorption capacity to some extent. CBHB showed a mixed mechanism by removing CIP through π-π electron donor-acceptor (EDA) interaction, hydrogen bonding and hydrophobic interaction. The reformation of CBHB with methanol and ethanol instead of water decreased its sorption capacity to 32.69 mg/g and 29.29 mg/g. Adsorption decreased by little after every regeneration of CBHB and was still >64 ±â€¯0.68% (25.73 mg/g) after 6th regeneration. The efficacy of CBHB for CIP removal proved that CBHB is an economical and sustainable adsorbent.


Assuntos
Carvão Vegetal/química , Ciprofloxacina/química , Hidrogéis/química , Poluentes Químicos da Água/química , Adsorção , Quitosana , Concentração de Íons de Hidrogênio , Cinética , Soluções
12.
Environ Sci Pollut Res Int ; 25(17): 17128-17136, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29644613

RESUMO

The interactions between antibiotics and microorganisms have attracted enormous research attentions. In this study, we investigated the effects of two typical aminoglycoside antibiotics on the aggregation of the model cyanobacterium, Synechococcus elongatus, and the dominating strain in algal blooms, Microcystis aeruginosa, via the analysis of zeta potentials, hydrophobicity, and extracellular polymeric substances (EPS) secretion. The results showed that low-level antibiotics promoted the aggregation of S. elongatus and M. aeruginosa by 40 and 18% under 0.10 and 0.02 µg/mL of kanamycin, respectively, which was mainly attributed to the combined effects of increased zeta potentials and the ratio between extracellular proteins and polysaccharides. Tobramycin exerted similar effects. Additionally, we discovered that at low pH (pH 5) and ionic strength (1 mM Na+ and 2 mM Mg2+), the inducing effects of antibiotics would be even larger than those with higher pH and ionic strength. As aggregation is important to cyanobacteria in either the basic physiology of biofilm formation or the algal bloom, our study demonstrated that low-level antibiotics exert ecological impacts via interfered aggregation. We believe this study will shed light on the mechanisms underlying antibiotic-induced biofilm formation and help with the evaluation of the environmental and ecological risks of antibiotics and other emerging pollutants.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Cianobactérias/metabolismo , Microcystis/efeitos dos fármacos , Polímeros/química , Aminoglicosídeos/química , Antibacterianos/química , Biofilmes , Cianobactérias/química , Eutrofização , Interações Hidrofóbicas e Hidrofílicas , Concentração Osmolar
13.
Colloids Surf B Biointerfaces ; 164: 20-26, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29367053

RESUMO

Development of novel approaches for biofouling mitigation is of crucial importance for membrane-based technologies. d-amino acids (d-AAs) have been proposed as a potential strategy to mitigate biofouling. However, the effect of bacterial cell-wall properties and d-AAs type on biofouling mitigation remains unclear. This study assesses the effect of d-AAs type on membrane biofouling control, towards Gram positive (G+) and Gram negative (G-) bacteria. Three kinds of d-AAs were found to inhibit both G+ and G- bacterial attachment in short-term attachment and dead-end filtration experiments. The existence of d-AAs reduces extracellular polysaccharides and proteins on the membrane, which may decrease membrane biofouling. Cross-flow filtration tests further indicated that d-AAs could effectively reduce membrane biofouling. The permeate flux recovery post chemical cleaning, improved for both P. aeruginosa and B. subtilis treated with d-AAs. The results obtained from this study enable better understanding of the role of d-AAs species on bacterial adhesion and biofilm formation. This may provide a new way to regulate biofilm formation by manipulating the species of d-AAs membrane systems.


Assuntos
Aminoácidos/farmacologia , Incrustação Biológica/prevenção & controle , Parede Celular/metabolismo , Membranas Artificiais , Bacillus subtilis/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Filtração , Polissacarídeos Bacterianos/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos
14.
J Mol Neurosci ; 64(1): 75-79, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29196882

RESUMO

The aim of this study was to explore whether schizophrenia occurrence is associated with polymorphisms in the 5' regulatory region of GABRB3 (gamma-aminobutyric acid type A receptor beta 3, subunit gene). The study included 324 patients with schizophrenia and 327 unaffected participants; all individuals were northern Han Chinese. Genotype and haplotype frequency distributions were compared for the 2 groups by means of PCR amplification and direct sequencing of the promoter region of GABRB3. The genotype distribution among control participants was in accordance with the Hardy-Weinberg equilibrium. Five common single-nucleotide polymorphism (SNP) sites were detected in the 5' promoter region of GABRB3: rs4243768, rs7171660, rs4363842, rs4906902, and rs8179184. Only rs8179184 and rs4906902 differed significantly in frequency between controls and cases (P < 0.05); this difference remained significant when only women in each group were compared. The 2 SNP sites showed linkage disequilibrium, resulting in 2 haplotypes: T-G and C-A. The frequency of C-A was significantly higher among patients with schizophrenia than among controls. Our findings suggest that rs4906902 and rs8179184 in the 5' promoter region of GABRB3 are associated with schizophrenia. The C-A haplotype may entail an increased risk of schizophrenia, and the onset of schizophrenia may be gender-specific.


Assuntos
Polimorfismo de Nucleotídeo Único , Receptores de GABA-A/genética , Esquizofrenia/genética , Feminino , Humanos , Desequilíbrio de Ligação , Masculino , Regiões Promotoras Genéticas
15.
Environ Sci Pollut Res Int ; 25(3): 2853-2860, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29143262

RESUMO

In this study, we evaluated the influences of graphene oxide (GO) on biofilm formation. Escherichia coli MG1655 and Bacillus subtilis 168 were used as models for Gram-negative and Gram-positive bacteria. The growth profiles and viability assays indicated that GO exhibited a high antibacterial activity, of which the negative effects on bacteria growth raised with the increasing GO concentration. The antibacterial activity of GO was mainly attributed to the membrane stress and ROS-independent oxidative stress. Moreover, it was worthy to note that the biofilm formation was enhanced in the presence of GO at low dosage whereas inhibited in the high-concentration GO environment. These results could be explained by the roles of the dead cells, which were inactivated by GO. When the concentration of GO was limited, only a part of the cells would be inactivated, which may then serve as a protection barrier as well as the necessary nutrient to the remaining living cells for the formation of biofilm. In contrast, with a sufficient presence of GO, almost all cells can be inactivated completely and thus the formation of biofilm could no longer be triggered. Overall, the present work provides significant new insights on the influence of carbon nanomaterials towards biofilm formation, which has far-reaching implications in the field of biofouling and membrane bioreactor. Graphical abstract ᅟ.


Assuntos
Bacillus subtilis/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Grafite/toxicidade , Poluentes Químicos da Água/toxicidade , Biofilmes/crescimento & desenvolvimento , Viabilidade Microbiana/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Óxidos
16.
Am J Chin Med ; 45(4): 863-877, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28595501

RESUMO

Astragaloside IV (AS-IV) is one of the active ingredients in Astragalus membrananceus (Huangqi), a traditional Chinese medicine. The present study investigated the effects of AS-IV on Ca[Formula: see text] handling in cardiac myocytes to elucidate its possible mechanism in the treatment of cardiac disease. The results showed that AS-IV at 1 and 10[Formula: see text][Formula: see text]M reduced KCl-induced [Ca[Formula: see text]]i increase ([Formula: see text] from 1.33[Formula: see text][Formula: see text][Formula: see text]0.04 (control, [Formula: see text] 28) to 1.22[Formula: see text][Formula: see text][Formula: see text]0.02 ([Formula: see text], [Formula: see text] 29) and 1.22[Formula: see text][Formula: see text][Formula: see text]0.02 ([Formula: see text] 0.01, [Formula: see text]), but it enhanced Ca[Formula: see text] release from SR ([Formula: see text] from 1.04[Formula: see text][Formula: see text][Formula: see text]0.01 (control, [Formula: see text]) to 1.44[Formula: see text][Formula: see text][Formula: see text]0.03 ([Formula: see text], [Formula: see text]) and 1.60[Formula: see text][Formula: see text][Formula: see text]0.04 ([Formula: see text] 0.01, [Formula: see text]0), in H9c2 cells. Similar results were obtained in native cardiomyocytes. AS-IV at 1 and 10[Formula: see text][Formula: see text]M inhibited L-type Ca[Formula: see text] current ([Formula: see text] from [Formula: see text]4.42[Formula: see text][Formula: see text][Formula: see text]0.58 pA/pF of control to [Formula: see text]2.25[Formula: see text][Formula: see text][Formula: see text]0.12 pA/pF ([Formula: see text] 0.01, [Formula: see text] 5) and [Formula: see text]1.78[Formula: see text][Formula: see text][Formula: see text]0.28 pA/pF ([Formula: see text] 0.01, [Formula: see text] 5) respectively, when the interference of [Ca[Formula: see text]]i was eliminated due to the depletion of SR Ca[Formula: see text] store by thapsigargin, an inhibitor of Ca[Formula: see text] ATPase. Moreover, when BAPTA, a rapid Ca[Formula: see text] chelator, was used, CDI (Ca[Formula: see text]-dependent inactivation) of [Formula: see text] was eliminated, and the inhibitory effects of AS-IV on ICaL were significantly reduced at the same time. These results suggest that AS-IV affects Ca[Formula: see text] homeostasis through two opposite pathways: inhibition of Ca[Formula: see text] influx through L-type Ca[Formula: see text] channel, and promotion of Ca[Formula: see text] release from SR.


Assuntos
Astragalus propinquus/química , Canais de Cálcio Tipo L/metabolismo , Cálcio/metabolismo , Membrana Celular/metabolismo , Miócitos Cardíacos/metabolismo , Saponinas/farmacologia , Retículo Sarcoplasmático/metabolismo , Triterpenos/farmacologia , Animais , Células Cultivadas , Depressão Química , Cobaias , Humanos , Miócitos Cardíacos/citologia , Técnicas de Patch-Clamp , Saponinas/isolamento & purificação , Estimulação Química , Triterpenos/isolamento & purificação
17.
Muscle Nerve ; 56(6): 1128-1136, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28044347

RESUMO

INTRODUCTION: Sepsis can cause decreased diaphragmatic contractility. Intracellular calcium as a second messenger is central to diaphragmatic contractility. However, changes in intracellular calcium concentration ([Ca2+ ]) and the distribution and co-localization of relevant calcium channels [dihydropyridine receptors, (DHPRα1s) and ryanodine receptors (RyR1)] remain unclear during sepsis. In this study we investigated the effect of changed intracellular [Ca2+ ] and expression and distribution of DHPRα1s and RyR1 on diaphragm function during sepsis. METHODS: We measured diaphragm contractility and isolated diaphragm muscle cells in a rat model of sepsis. The distribution and co-localization of DHPRα1s and RyR1 were determined using immunohistochemistry and immunofluorescence, whereas intracellular [Ca2+ ] was measured by confocal microscopy and fluorescence spectrophotometry. RESULTS: Septic rat diaphragm contractility, expression of DHPRα1s and RyR1, and intracellular [Ca2+ ] were significantly decreased in the rat sepsis model compared with controls. DISCUSSION: Decreased intracellular [Ca2+ ] coincides with diaphragmatic contractility and decreased expression of DHPRα1s and RyR1 in sepsis. Muscle Nerve 56: 1128-1136, 2017.


Assuntos
Canais de Cálcio Tipo L/biossíntese , Cálcio/metabolismo , Diafragma/metabolismo , Líquido Intracelular/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/biossíntese , Sepse/metabolismo , Animais , Canais de Cálcio Tipo L/genética , Diafragma/fisiopatologia , Expressão Gênica , Masculino , Contração Muscular/fisiologia , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Sepse/genética , Sepse/fisiopatologia
18.
Sci Rep ; 6: 34713, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27698421

RESUMO

Effective pulp-capping materials must have antibacterial properties and induce dentin bridge formation; however, many current materials do not satisfy clinical requirements. Accordingly, the effects of an experiment pulp-capping material (Exp) composed of an antibacterial resin monomer (MAE-DB) and Portland cement (PC) on the viability, adhesion, migration, and differentiation of human dental pulp stem cells (hDPSCs) were examined. Based on a Cell Counting Kit-8 assay, hDPSCs exposed to Exp extracts showed limited viability at 24 and 48 h, but displayed comparable viability to the control at 72 h. hDPSC treatment with Exp extracts enhanced cellular adhesion and migration according to in vitro scratch wound healing and Transwell migration assays. Exp significantly upregulated the expression of osteogenesis-related genes. The hDPSCs cultured with Exp exhibited higher ALP activity and calcium deposition in vitro compared with the control group. The novel material showed comparable cytocompatibility to control cells and promoted the adhesion, migration, and osteogenic differentiation of hDPSCs, indicating excellent biocompatibility. This new direct pulp-capping material containing MAE-DB and PC shows promise as a potential alternative to conventional materials for direct pulp capping.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Cimentos Dentários/farmacologia , Polpa Dentária/efeitos dos fármacos , Metacrilatos/farmacologia , Osteogênese/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , Células-Tronco/efeitos dos fármacos , Adolescente , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Dente Pré-Molar/citologia , Dente Pré-Molar/cirurgia , Bioensaio , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Polpa Dentária/citologia , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Dente Molar/citologia , Dente Molar/cirurgia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteocalcina/genética , Osteocalcina/metabolismo , Osteogênese/genética , Osteonectina/genética , Osteonectina/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Cultura Primária de Células , Sialoglicoproteínas/genética , Sialoglicoproteínas/metabolismo , Células-Tronco/citologia , Extração Dentária , Cicatrização/efeitos dos fármacos , Adulto Jovem
19.
Mol Clin Oncol ; 3(4): 949-953, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26171213

RESUMO

The incidence of primary central nervous system lymphoma (PCNSL) has increased in the last two decades and the clinical research regarding the treatment for PCNSL patients has also increased. However, the optimal induction chemotherapy has not been fully established. In the present retrospective study, the aim was to analyze the outcome in PCNSL patients treated with the combination of rituximab, methotrexate (MTX), cytarabine (Ara-C) and dexamethasone (R-MAD). Eighteen patients from Beijing Tiantan Hospital (Beijing, China) between January 2010 and March 2014 were newly diagnosed with PCNSL [diffuse large B-cell lymphoma (DLBCL) type] and received R-MAD as first-line treatment. The dosage was as follows: 375 mg/m2 rituximab was administered on day 0, 3.5 g/m2 MTX was administered on day 1, 1 g/m2 Ara-C was administered on day 2 and 10 mg dexamethasone was administered on days 1-3, every 3 weeks. After 6 cycles, the overall response rate was 94.5%. Ten (55.6%) patients achieved complete response (CR), 7 (38.9%) achieved partial response (PR) and 1 (5.6%) had progressive disease (PD). Patients were followed up from the start of the treatment, median 24.2 months (range 6-48). The overall survival (OS) rate was 94.5% and progression-free survival rate was 94.5%. The median OS was 22 months (95% confidence interval, 19.4-24.6). The high level of serum lactate dehydrogenase (LDH) concentration was associated with a poor outcome. Among 5 patients with an abnormally high LDH concentration, 1 achieved CR, 3 had PR and 1 had PD. None of the patients experienced any grade 4 toxicity. These results indicated that the R-MAD immunochemotherapy regimen is effective in PCNSL patients without serious toxicity. A prospective investigation with more patients should be administered in order to understand the more accurate effect of the regimen.

20.
Asian Pac J Cancer Prev ; 16(3): 997-1000, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25735395

RESUMO

Esophageal cancer represents the fourth most common gastrointestinal cancer and generally confers a poor prognosis. Prostaglandin-producing cyclo-oxygenase has been implicated in the pathogenesis of esophageal cancer growth. Here we report that prostaglandin dehydrogenase, the major enzyme responsible for prostaglandin degradation, is significantly reduced in expression in esophageal cancer in comparison to normal esophageal tissue. Reconstitution of PGDH expression in esophageal cancer cells suppresses cancer cell growth, at least in part through preventing cell proliferation and promoting cell apoptosis. The tumor suppressive role of PGDH applies equally to both squamous cell carcinoma and adenocarcinoma, which enriches our understanding of the pathogenesis of esophageal cancer and may provide an important therapeutic target.


Assuntos
Adenocarcinoma/patologia , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Neoplasias Esofágicas/patologia , Hidroxiprostaglandina Desidrogenases/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Apoptose , Western Blotting , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Humanos , Hidroxiprostaglandina Desidrogenases/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
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