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1.
Environ Sci Technol ; 57(9): 4050-4059, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36802506

RESUMO

Converting biomass into biochar (BC) as a functional biocatalyst to accelerate persulfate activation for water remediation has attracted much attention. However, due to the complex structure of BC and the difficulty in identifying the intrinsic active sites, it is essential to understand the link between various properties of BC and the corresponding mechanisms promoting nonradicals. Machine learning (ML) recently demonstrated significant potential for material design and property enhancement to help tackle this problem. Herein, ML techniques were applied to guide the rational design of BC for the targeted acceleration of nonradical pathways. The results showed a high specific surface area, and O% values can significantly enhance nonradical contribution. Furthermore, the two features can be regulated by simultaneously tuning the temperatures and biomass precursors for efficient directed nonradical degradation. Finally, two nonradical-enhanced BCs with different active sites were prepared based on the ML results. This work serves as a proof of concept for applying ML in the synthesis of tailored BC for persulfate activation, thereby revealing the remarkable capability of ML for accelerating bio-based catalyst development.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Oxirredução , Carvão Vegetal/química , Catálise , Temperatura , Poluentes Químicos da Água/análise
2.
Nano Lett ; 22(22): 9154-9162, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36342406

RESUMO

Autophagy is one of the key pathways for tumor cell survival and proliferation. Therefore, inhibition of autophagy has been extensively studied for cancer therapy. However, current autophagy inhibitors lack specificity and are ineffective in limiting tumor progression. Herein, we report a nanoplatform for tumor-site-targeted delivery of hydroxychloroquine (HCQ) using insulin-like growth factors 2 receptor (IGF2R)-targeted liposomes (iLipo-H). A fasting-mimicking diet (FMD) is used to increase the autophagy levels in tumor cells, thereby increasing the sensitivity of tumor cells to HCQ. In addition, FMD treatment upregulates the expression of IGF2R in tumor cells, but not normal cells. Consequently, iLipo-H nanoparticles efficiently accumulate at the tumor site under FMD condition. In vivo studies demonstrate that iLipo-H nanoparticles efficiently inhibit 4T1 tumor growth without obvious side effects, especially under FMD condition. This study provides a promising strategy to increase the sensitivity of tumor cells to autophagy inhibitors for effective cancer therapy.


Assuntos
Jejum , Neoplasias , Humanos , Autofagia , Lisossomos , Hidroxicloroquina/farmacologia , Hidroxicloroquina/uso terapêutico , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
3.
Environ Monit Assess ; 191(3): 162, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771016

RESUMO

This study demonstrates characteristics and mechanisms of deformation of an aquifer system in response to seasonal fluctuations of groundwater level when groundwater pumping has been strictly regulated after experiencing longtime land subsidence. Two boreholes with depth of 1226 m (G2 site) and 905 m (G3 site) were drilled at the Tianjin coastal region where severe land subsidence had occurred since the 1950s. Extensometer/piezometer groups installed at the G2 site illustrate synchronized variations of compaction and groundwater level since 2010 in the aquifer system between depth of 100-400 m which contributes most groundwater pumpage. Monitored land subsidence demonstrates that the shallow aquifer has become the main contributor to the land subsidence, and inelastic compaction still occurred in the aquifers where groundwater level has recovered. Pre-consolidation stresses show that clayey soils in depth < 100 m are under-consolidated, and deep clayey soils show the state of normal- to over-consolidation. The effects of the cyclic groundwater level oscillation on deformation were investigated using repeated loading and unloading tests. Void ratio changes in loading/unloading cycles illustrate that inelastic deformation rate decreases gradually and elastic deformation rate remains almost unchanged with increases of cyclic numbers. The deformation of soil samples from 100 to 400 m is mostly elastic for loading stress in the over-consolidation stress range. These findings suggest that groundwater dewatering in the shallow (depth < 100 m) aquifer will be the primary target to control land subsidence. Groundwater level fluctuations higher than pre-consolidation value in 100-400 m only lead to elastic and recoverable deformation even small residual permanent deformation may continue for a long time. The results improve the understanding of deformation in complex urban aquifers affected by groundwater level fluctuations and highlight the importance of city planning management for controlling land subsidence in coastal cities.


Assuntos
Monitoramento Ambiental , Água Subterrânea/análise , Abastecimento de Água/estatística & dados numéricos , China , Cidades , Água Subterrânea/química , Solo
4.
Opt Express ; 23(15): 19673-80, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26367624

RESUMO

We propose and experimentally demonstrate a fast polarization tracking scheme based on radius-directed linear Kalman filter. It has the advantages of fast convergence and is inherently insensitive to phase noise and frequency offset effects. The scheme is experimentally compared to conventional polarization tracking methods on the polarization rotation angular frequency. The results show that better tracking capability with more than one order of magnitude improvement is obtained in the cases of polarization multiplexed QPSK and 16QAM signals. The influences of the filter tuning parameters on tracking performance are also investigated in detail.

5.
Zhonghua Xin Xue Guan Bing Za Zhi ; 43(6): 516-20, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26420120

RESUMO

OBJECTIVE: To observe the serum expression of miR-181b in atherosclerotic patients and the in vitro effects of miR-181b on vascular smooth muscle cell growth and migration. METHODS: Fifty patients (mean age: (78.1 ± 8.9) years old) with carotid ultrasound examination evidenced atherosclerotic plaque were enrolled as the atherosclerosis group and 50 healthy (mean age: (72.5 ± 10.7) years old) subjects serve as control group. Stem-loop real time RT-PCR was used to detect the serum expression of miR-181b. Importin-α3 was predicted to be a direct target of miR-181b by Targetscan and Pictar. Western-blot was employed to detect the in vitro effects of miR-181b on the expression of Importin-α3 in endothelial cells. Luciferase reporter assay was employed to testify the prediction. The effects of miR-181b on vascular smooth muscle cell growth, migration abilities were respectively examined by CCK8 assay and Matrigel migration assay. RESULTS: Compared with healthy controls, serum expression of miR-181b was significantly down-regulated in patients with atherosclerosis (31.69 ± 0.96 vs. 82.28 ± 5.95, P < 0.05); Importin-α3 was predicted and proved to be a direct target of miR-181b by Western-blot and luciferase reporter assay. The proliferation and migration of vascular smooth muscle cell were significantly downregulated by forced expression of miR-181b (1.57 ± 0.18 vs. 2.66 ± 0.16, P < 0.05; 8.7 ± 1.1 vs. 21.4 ± 2.3, P < 0.05), while these effects could be abolished by inhibition of miR-181b (2.88 ± 0.09 vs. 2.04 ± 0.11, P < 0.05; 15.2 ± 1.5 vs. 8.4 ± 1.3, P < 0.05). CONCLUSION: The serum miR-181b level was significantly reduced in patients with atherosclerosis. miR-181b may function as an atherosclerosis suppressor by interupting the NF-κB pathway in endothelial cells and inhibiting the proliferation and migration of vascular smooth muscle cells.


Assuntos
Aterosclerose , MicroRNAs , Idoso , Idoso de 80 Anos ou mais , Ciclo Celular , Proliferação de Células , Regulação para Baixo , Células Endoteliais , Humanos , Músculo Liso Vascular , NF-kappa B
6.
Int J Clin Pharmacol Ther ; 52(6): 454-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24755126

RESUMO

OBJECTIVE: To compare the therapeutic warfarin and aspirin efficacies for treatments of atrial fibrillation (AF) complicated with stable coronary heart disease particularly in older Chinese patients. METHODS: In our prospective study 101 patients with AF and stable coronary heart disease older than 80 years were randomized into two groups. One group (n = 51) basically received 1.25 mg/day warfarin per os, followed by addition of 0.5 - 1.0 mg/day from day 3 - 5 if the international normalized ratio (INR) was initially < 1.5 and in order to achieve a maintained INR between 1.6 and 2.5 (warfarin group). The second group (n = 50) received 100 mg aspirin per day (control group). All patients were medicated and monitored for a period of 2 years. The primary endpoint was the occurrence of ischemic stroke or systemic embolism, and the composite secondary endpoint was non-fatal myocardial infarction and all causes of death. For safety evaluation, the hemorrhage rates were recorded. RESULTS: The warfarin medication was superior regarding the overall occurrence of ischemic stroke or systemic embolism as well as non-fatal myocardial infarction and all causes of death outcomes compared to aspirin administration during the 2 years of medication (17.6% vs. 36.0%, p = 0.03), while there was no significant difference of mild (5 vs. 4), severe (2 vs. 1), and fatal (1 vs. 1) hemorrhage incidences between the warfarin and aspirin groups (p > 0.05). CONCLUSION: Warfarin was found to be more efficacious than aspirin for an anticoagulation therapy of older Chinese patients with AF and stable coronary heart disease.


Assuntos
Anticoagulantes/uso terapêutico , Aspirina/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Coagulação Sanguínea/efeitos dos fármacos , Doença das Coronárias/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Varfarina/uso terapêutico , Fatores Etários , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Aspirina/efeitos adversos , Fibrilação Atrial/sangue , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/mortalidade , China , Doença das Coronárias/sangue , Doença das Coronárias/complicações , Doença das Coronárias/diagnóstico , Doença das Coronárias/mortalidade , Feminino , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado , Masculino , Estudos Prospectivos , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo , Resultado do Tratamento , Varfarina/efeitos adversos
7.
Environ Sci Pollut Res Int ; 31(8): 12094-12111, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38225495

RESUMO

Anthropogenic groundwater arsenic (As) pollution is common in many aquifers in Southwest China. It is concerned that long-term random disposal of As smelting slag could induce the transport of high-As groundwater into previously uncontaminated aquifers. Here, we used HELP-MODFLOW-MT3DMS model simulations to integrate the percolation, groundwater flow, and solute transport processes at an aquifer at site scale, constrained by weather, hydrogeology, and monitoring data. Our simulations provide a new method framework of the simulated percolation by HELP model and have induced As spatiotemporal distribution in the aquifer. According to the HELP model simulation results, percolation volume accounts for 24% of rainfall over 18 years. This work determined that the As discharge trend was fitted by double-constants kinetics based on the leaching experiment. And this work calculates total mass distribution of As in the aquifer over 18 years. We have found that the sustained As pollution relies on the rainfall that acts as the primary contributor of elevated As concentrations. Model simulation results suggest that 51.70% of the total As mass (1.96 × 104 kg) was fixed in low permeability solid media. The total As mass discharged into groundwater reached 9.3 × 103 kg, accounting for 24.68%. The accumulative outflow mass of arsenic was 8.0 × 103 kg, accounting for 21.62%.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , China , Simulação por Computador , Poluição Ambiental , Monitoramento Ambiental , Poluentes Químicos da Água/análise
8.
Environ Manage ; 51(6): 1109-25, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23604266

RESUMO

Land subsidence caused by extensive groundwater pumping has become a factor which cannot be ignored in the sustainable exploitation of groundwater resources. The Hangzhou-Jiaxing-Huzhou Plain is one of the locations with China's most severe land subsidence problems; the region has experienced dramatic land subsidence since the 1960s. Historical records of groundwater extraction, hydraulic head, and land subsidence show the latter to be the result of continual and excessive extraction of groundwater from deep confined aquifers. This study reconstructs land subsidence using an integrated regional groundwater flow and land subsidence model. The model is calibrated using land subsidence and groundwater level measurements from 1996 to 2007. Simulation results reproduce the cones of depression for groundwater heads and nadirs of land subsidence reasonably well. The calibrated model is used to evaluate the efficacy of land subsidence prevention plans from 2008 to 2010, and to predict future land subsidence over the next decade considering several groundwater exploitation scenarios. The results show the main cause of land subsidence to be inelastic compaction of the aquifer system resulting from continuously declining water levels. The model reveals that while the area of land subsidence will continue to extend, the rate of this extension may be significantly decreased by reduction of groundwater extraction. If the current land subsidence prevention and reclamation plans are continued and surface water diversion projects implemented, though land subsidence cannot be halted, the rate at which it is occurring can be effectively reduced.


Assuntos
Água Subterrânea , Modelos Teóricos , China , Conservação dos Recursos Naturais , Fenômenos Geológicos
9.
Adv Healthc Mater ; 12(29): e2302187, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37607115

RESUMO

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in the treatment of non-small cell lung cancer (NSCLC) still face challenges of acquired resistance and non-negligible side effects. To overcome these limitations, a biodegradable coordination polymer using guanine deoxynucleotide and ferrous iron (dGNP) is developed for targeted delivery of EGFR-TKIs. dGNPs can efficiently target nucleoside transporters in tumor cells that are regulated by fasting-mimicking diet (FMD). Meanwhile, FMD can augment the therapeutic efficacy of EGFR-TKIs by suppressing EGFR tyrosine kinase phosphorylation and related downstream pathways. In vivo results demonstrate that EGFR-TKIs-laden dGNPs combined with FMD treatment exhibit superior antitumor efficacy and reduced side effect. This study provides an innovative approach to enhance the therapeutic efficacy of EGFR-TKIs through nucleotide nanocarrier and metabolic modulation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Nucleotídeos/farmacologia , Receptores ErbB , Inibidores de Proteínas Quinases/uso terapêutico , Resistencia a Medicamentos Antineoplásicos
10.
Adv Healthc Mater ; 12(15): e2202943, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36773308

RESUMO

Synergistic photodynamic and photothermal therapy (PDT-PTT) has emerged as an appealing effective antitumor approach. However, clinical utilization of PDT-PTT is plagued by aggregation-caused photobleaching, sequential double irradiations, unsatisfying balance between single oxygen (1 O2 ) quantum yield and photothermal conversion efficiency. Here, an anchored tumor-homing cell-penetrating peptide (PEGA-pVEC) and PANI-ES/HMME loaded FRET nanobullet (AHP-P) are reported. Within nanobullet, HMME (donor) and PANI-ES (acceptor) spontaneously form a förster resonance energy transfer (FRET) pair. Upon 660 nm laser irradiation, HMME convert near-infrared fluorescence (NIRF) to PANI, thus produce FRET-amplified photoacoustic imaging guided PTT. In addition, AHP-P with pH-sensitivity can gradually release HMME within acidic tumor environment, boosts the 1 O2 regeneration alongside with highly efficient photothermal conversion for photoinduced cancer PTT-PDT. Furthermore, the AHP-P nanobullet can home in on the tumor site and penetrate into cytoplasm through PEGA-pVEC, inducing remarkable tumor regression with an ≈80% tumor volume reduction and decreased skin phototoxicity in vivo during FRET-amplified PTT-PDT.


Assuntos
Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Transferência Ressonante de Energia de Fluorescência , Terapia Fototérmica , Técnicas Fotoacústicas/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Fototerapia/métodos , Nanopartículas/uso terapêutico
11.
J Med Chem ; 66(9): 6263-6273, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37092695

RESUMO

Proteolysis-targeting chimera (PROTAC) has emerged as a promising strategy for degrading proteins of interest. Peptide-based PROTACs offer several advantages over small-molecule-based PROTACs, such as high specificity, low toxicity, and large protein-protein interaction surfaces. However, peptide-based PROTACs have several intrinsic shortcomings that strongly limit their application including poor cell permeability and low stability and potency. Herein, we designed a nanosized hybrid PROTAC (GNCTACs) to target and degrade human epidermal growth factor receptor 2 (HER2) in tumor cells. Gold nanoclusters (GNCs) were utilized to connect HER2-targeting peptides and cereblon (CRBN)-targeting ligands. GNCTACs could overcome the intrinsic barriers of peptide-based PROTACs, efficiently delivering HER2-targeting peptides in the cytoplasm and protecting them from degradation. Furthermore, a fasting-mimicking diet was applied to enhance the cellular uptake and proteasome activity. Consequently, more than 95% of HER2 in SKBR3 cells was degraded by GNCTACs, and the degradation lasted for at least 72 h, showing a catalytic-like reaction.


Assuntos
Apoptose , Proteínas , Humanos , Proteínas/metabolismo , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Quimera de Direcionamento de Proteólise
12.
Adv Mater ; 34(47): e2205950, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36217832

RESUMO

Dendritic cells (DCs)-based vaccines are an approved method for inducing potent antigen-specific immune responses to eliminate tumor cells. However, this promising strategy still faces challenges such as tumor-associated antigens (TAAs) loading, lymph node homing, quality control, and other limitations. Here, a personalized DC-mimicking nanovaccine (nanoDC) for stimulation of TAAs-specific T cell populations is developed. The nanoDCs are fabricated using nanoparticles with dendritic structure and membranes from mature bone-marrow-derived cells (BMDCs). Mature BMDCs are stimulated by nanostructures assembled from Escherichia coli and tumor cells to efficiently deliver TAAs and induce BMDCs maturation through the stimulator of interferon genes (STING) pathway. By maintaining co-stimulatory markers, molecules class I (MHC-I) antigen complexes and lymphocyte homing receptors, nanoDCs efficiently migrate to lymph nodes and generate potent antigen-specific T cell responses. Consequently, vaccination with nanoDCs strongly inhibits the tumor growth and metastases formation in vivo. In particular, nanoDCs can also induce memory T cells for long-term protective immunity. This study demonstrates that nanoDCs can trigger adaptive immune protection against tumors for personalized immunotherapy and precision medicine.


Assuntos
Células Dendríticas , Neoplasias , Animais , Camundongos , Antígenos de Neoplasias , Imunoterapia/métodos , Imunidade Adaptativa , Camundongos Endogâmicos C57BL
13.
Front Nutr ; 9: 1026678, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386911

RESUMO

In this study, the cyclodextrin glucosyltransferase (CGTase) was extracted from Bacillus xiaoxiensis. CGTase had negative effects on dough viscoelastic properties and gluten strength but had positive effects on bread baking qualities and anti-staling properties. Adding an appropriate amount of CGTase (less than 0.3 U/g) could improve the specific volume, crumb texture, crust color, moisture content, and crumb hardness of bread. The bread crumb with 0.4 U/g CGTase (based on flour weight) had the lowest retrogradation enthalpy of 0.53 ± 0.10 J/g and the lowest relative crystallinity of 16.1%, which indicated the alleviating effect of amylopectin crystallization. Moreover, CGTase reduced the moisture from forming crystal lattices and limited starch molecule migration. The T2 transverse relaxation results showed that the increase of immobilized water content in the bread with CGTase was lower than the control after 5 days of storage, which implied the water-holding capacity of the bread was enhanced and provided information on the inhibition of water migration. Hence, the CGTase could be a potential bread improver.

14.
Water Res ; 206: 117741, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655934

RESUMO

In this study, we applied a flexible strategy to manufacture a microalgal biochar-based membrane (MBCM). Due to the hierarchical surface topography on a micro-nano scale, the MBCM was found to have both underwater superoleophobic and underoil superhydrophobic properties. Combining an underoil superhydrophobic oil-containing region (OCR) with an underwater superoleophobic water-containing region (WCR) achieved the successive filtration of multiphase emulsions. The MBCM also served as a high-performance carbocatalyst for advanced oxidation processes (AOPs), due to the N functionalities (5.08%) of the graphene-like structure. This was caused by the high-temperature pyrolysis of rich proteins and alkaline salts in the algal residue. As a result, the MBCM/AOPs system achieved greater than 99.5% emulsions separation efficiency in different emulsion mixtures, while also achieving an outstanding degradation rate (99.8%) of soluble organic contaminants (SOCs). This in-depth exploration resulted in a low-cost and green strategy for developing multifunctional membranes to treat complex wastewater. The paper explains the mechanisms used by MBCM to synchronously remove emulsions and SOCs from wastewater.


Assuntos
Microalgas , Purificação da Água , Emulsões , Filtração , Águas Residuárias
15.
Ground Water ; 59(1): 90-99, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32700342

RESUMO

MODFLOW is one of the most popular groundwater simulation tools available; however, the development of lake modules that can be coupled with MODFLOW is lacking apart from the LAK3 package. This study proposes a new approach for simulating lake-groundwater interaction under steady-state flow, referred to as the sloping lakebed method (SLM). In this new approach, discretization of the lakebed in the vertical direction is independent of the spatial discretization of the aquifer system, which can potentially solve the problem that the lake and groundwater are usually simulated at different scales. The lakebed is generalized by a slant at the bottom of each lake grid cell, which can be classified as fully submerged, dry, and partly submerged. The SLM method accounts for all lake sources and sinks, establishing a governing equation that can be solved using Newton's method. A benchmarking case study was conducted using a modified model setup in the LAK3 user manual. It was found that when there is a sufficient number of layers at the top of the groundwater model, SLM simulates an almost identical groundwater head as the LAK3-based model; when the number of layers decreases, SLM is unaffected while LAK3 may be at a risk of giving unrealistic results. Additionally, the SLM can reflect the relationship between the simulated lake surface area and lake water depth more accurately. Therefore, the SLM method is a promising alternative to the LAK3 package when simulating lake-groundwater interaction.


Assuntos
Água Subterrânea , Simulação por Computador , Lagos , Modelos Teóricos , Movimentos da Água
16.
ACS Nano ; 15(9): 14347-14359, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34472328

RESUMO

The successful control of coronavirus disease 2019 (COVID-19) pandemic is not only relying on the development of vaccines, but also depending on the storage, transportation, and administration of vaccines. Ideally, nucleic acid vaccine should be directly delivered to proper immune cells or tissue (such as lymph nodes). However, current developed vaccines are normally treated through intramuscular injection, where immune cells do not normally reside. Meanwhile, current nucleic acid vaccines must be stored in a frozen state that may hinder their application in developing countries. Here, we report a separable microneedle (SMN) patch to deliver polymer encapsulated spike (or nucleocapsid) protein encoding DNA vaccines and immune adjuvant for efficient immunization. Compared with intramuscular injection, SMN patch can deliver nanovaccines into intradermal for inducing potent and durable adaptive immunity. IFN-γ+CD4/8+ and IL-2+CD4/8+ T cells or virus specific IgG are significantly increased after vaccination. Moreover, in vivo results show the SMN patches can be stored at room temperature for at least 30 days without decreases in immune responses. These features of nanovaccines-laden SMN patch are important for developing advanced COVID-19 vaccines with global accessibility.


Assuntos
Vacinas contra COVID-19 , COVID-19 , DNA , Humanos , Agulhas , SARS-CoV-2 , Vacinação
17.
Process Saf Environ Prot ; 139: 230-240, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32372848

RESUMO

Landfill leachate poses significant risks to public health via the release of high-toxicity contaminants, including refractory organic compounds, ammonia-nitrogen compounds, and heavy metals. Significant efforts have been made to develop useful methods for leachate disposition and treatment. Advanced oxidation processes (AOPs) are one of the most promising methods, because they can rapidly degrade diverse pollutants and significantly improve the biodegradability of leachate. Graphitic carbon nitride (g-C3N4), a fascinating conjugated polymer, has become a hot topic in AOP research due to its metal-free benefits and high photosensitivity. Thus, combining AOPs with g-C3N4 achieves excellent degradation of refractory pollutants in leachate. Since the composition of leachate is complex in the practical conditions, the information reported by current studies of using g-C3N4 as a remediator is still incomplete and fragmented. Thus, in this review, the recent status of leachate treatment and approaches for its disposal has been summarized and some conclusions have been drawn. In addition, a brief introduction to g-C3N4 and its application in AOPs for leachate treatment have been critically discussed and with its future outlook assessed. Although the development of g-C3N4 in AOPs for leachate treatment is highly efficient and practical, comprehensive study about its application and technology expansion is urgently needed, based on the complex operating conditions. Perspectives on the treatment of leachate using g-C3N4-AOPs are also included. The information and perspectives provided in this review will provide guidance and novel understanding to accelerate the development of g-C3N4-based AOPs for leachate treatment.

18.
Oncol Lett ; 19(1): 350-358, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31897147

RESUMO

Cisplatin (DDP) resistance is closely associated with the failure of chemotherapy to manage various different types of human cancer. The GTPase protein Ras-related protein Rap-2a (RAP2A) regulates cancer cell proliferation, migration and invasion; however, little is currently known regarding its role in cancer cell resistance to chemotherapy. The present study investigated the potential roles of the RAP2A gene in gastric cancer cell resistance to DDP treatment. The DDP half maximal inhibitory concentration (IC50) values for the proliferation inhibition of MGC803 and MGC803/DDP gastric cancer cells were determined by treating the cells with a DDP concentration gradient and measuring their survival rates using the Cell Counting Kit-8 (CCK-8) assay; cell viability was also assessed using the CCK-8 assay. Cell migration and invasion were assessed using Transwell Matrigel assays, and apoptosis and DNA damage were evaluated using flow cytometry and Hoechst staining. RAP2A expression was knocked down by siRNA transfection, and RAP2A protein levels were examined using western blotting. The DDP IC50 values for DDP-resistant MGC803/DDP cells were greater than those for MGC803 cells. Furthermore, MGC803/DDP cells exhibited increased levels of viability, migration and invasion, and decreased levels of apoptosis and DNA damage during DDP treatment. Knockdown of RAP2A expression significantly promoted MGC803/DDP cell apoptosis and DNA damage, and decreased the viability and invasion capabilities of these cells following treatment with DDP. The results of the present study revealed that RAP2A expression promotes DDP resistance in gastric cancer cells by increasing their viability, migration and invasion capacities, and by suppressing apoptosis and DNA damage.

19.
J Hazard Mater ; 388: 121773, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31836373

RESUMO

Plastic products have become a major contaminant in environmental ecology due to their recalcitrant biodegradation, poor management and risky disposal. Therefore, much research attention has been paid to developing the biodegradable bio-based plastics. However, many of the substitute bioplastics derived from agricultural materials may present a potential threat to food security and eco-systems. Herein, we propose a sustainable, eco-friendly and simple procedure to convert the hazardous high-salt contained microalgal residues into bioplastic film. With 35 % poly (vinyl alcohol) (PVA) assistance, the composite bioplastic films achieved 22 MPa tensile strength under alkali condition and 77 % elongation at break under acidic condition. The average maximum contact angle of 94.4° confirmed a desirable water resistance potential. The synthesis mechanism demonstrated that the inorganic salts existed in microalgal residues could act as the filler in shape of sheets under alkali condition or as the cross linker under acidic condition, significantly enhancing the practical feasibility. This work demonstrates a promising biodegradable bioplastics formed from sustainable eco-friendly waste reutilization process, providing a new insight for fundamentally reducing the plastics pollution.


Assuntos
Plásticos/química , Spirulina , Resíduos , Conservação dos Recursos Naturais , Poluição Ambiental , Reciclagem , Sais
20.
ACS Appl Mater Interfaces ; 12(19): 22387-22397, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32321236

RESUMO

Seawater desalination via solar energy has potential to alleviate freshwater scarcity. However, problems including insufficient air-water interface, large heat loss, and potential ecological impact have restricted its practical viability. Here, a novel wood-derived indirect-contact (hanging) photothermal evaporation system was designed. An evaporation rate of 1.351 kg·m-2·h-1 with efficiency up to 90.89% under one sun illumination (1 kW·m-2) was achieved, which is the highest record to the best of our knowledge. More importantly, a series of simulations and numerical modeling were carried out to analyze the main factors affecting seawater collection and evaporation, and the synergetic mechanisms of oriented seawater collection, photothermal thermogenesis, and natural convection were elucidated. Taken together, this study provides a new wood-derived hanging seawater desalination system with superior mechanical strength, good repeatability, great ecological security, and excellent thermal stability. The corresponding mechanisms of the whole process are shown, and the seawater evaporation efficiency approaching the real demand is maximized.

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