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1.
Nanomaterials (Basel) ; 14(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38334586

RESUMO

The construction of semiconductor heterojunction photocatalysts that improve the separation and transfer of photoinduced charge carriers is an effective and widely employed strategy to boost photocatalytic performance. Herein, we have successfully constructed a CdS/Ag/Bi2WO6 Z-scheme heterojunction with an Ag-bridge as an effective charge transfer channel by a facile process. The heterostructure consists of both CdS and Ag nanoparticles anchored on the surface of Bi2WO6 nanosheets. The photocatalytic efficiency of the CdS/Ag/Bi2WO6 system was studied by the decontamination of tetracycline (TC) and Rhodamine B (RhB) under visible light irradiation (λ ≥ 420). The results exhibited that CdS/Ag/Bi2WO6 shows markedly higher photocatalytic performance than that of CdS, Bi2WO6, Ag/Bi2WO6, and CdS/Bi2WO6. The trapping experiment results verified that the •O2- and h+ radicals are the key active species. The results of photoluminescence spectral analysis and photocurrent responses indicated that the CdS/Ag/Bi2WO6 heterojunctions exhibit exceptional efficiency in separating and transferring photoinduced electron-hole pairs. Based on a series of characterization results, the boosted photocatalytic activity of the CdS/Ag/Bi2WO6 system is mostly due to the successful formation of the Ag-bridged Z-scheme heterojunction; these can not only inhibit the recombination rate of photoinduced charge carriers but also possess a splendid redox capacity. The work provides a way for designing a Z-scheme photocatalytic system based on Ag-bridged for boosting photocatalytic performance.

2.
J Nat Prod ; 86(6): 1449-1462, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37243616

RESUMO

Colorectal cancer (CRC) is an exceptionally deadly disease, whereas effective therapeutic drugs for CRC have declined over the past few decades. Natural products have become a reliable source of anticancer drugs. Previously we isolated an alkaloid named (-)-N-hydroxyapiosporamide (NHAP), which exerts potent antitumor effects, but its effect and mechanism in CRC remain unclear. This study aimed to reveal the antitumor target of NHAP and identify NHAP as a promising lead compound for CRC. Various biochemical methods and animal models were used to investigate the antitumor effect and molecular mechanism for NHAP. These results showed that NHAP exhibited potent cytotoxicity, induced both apoptosis and autophagic cell death of CRC cells, and inhibited the NF-κB signaling pathway by blocking the interaction of the TAK1-TRAF6 complex. NHAP also markedly inhibited CRC tumor growth in vivo without obvious toxicities and possessed good pharmacokinetic characteristics. These findings identify, for the first time, that NHAP is an NF-κB inhibitor with potent antitumor activity in vitro and in vivo. This study clarifies the antitumor target of NHAP against CRC, which will contribute to the future development of NHAP as a novel therapeutic lead compound for CRC.


Assuntos
Alcaloides , Antineoplásicos , Neoplasias Colorretais , Animais , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , NF-kappa B/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Fator 6 Associado a Receptor de TNF/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
3.
J Org Chem ; 87(21): 14058-14067, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36162105

RESUMO

Two highly oxygenated pentacyclic polyketides with two new carbon skeletons, trichopsistide A (1) and trichopsistide B (2), were isolated from the plant endophyte Trichoderma koningiopsis WZ-196 derived from the leaf of Rubia podantha Diels. The structures of these polyketides with full configurations were determined by comprehensive spectroscopic analysis, computer-assisted structure elucidation software, computational calculation, and X-ray crystal diffraction. Among them, 1 represented the first example of an unprecedented 5/6/6/6/5 pentacyclic ketal-containing polyketide pyridine alkaloid, and 2 possessed a novel 6/6/6/6/5 pentacyclic ketal-containing polyketide scaffold fused with an α-pyrone. The plausible biosynthetic route for 1 and 2 was also proposed. Moreover, biological activity assays showed that 1 and 2 possessed inhibitory effects on the NF-κB signaling pathway with IC50 values of 14.77 and 8.58 µM, respectively. Furthermore, 1 and 2 could also inhibit the expression of IκBα and p65 phosphorylation, decrease the expression of MCP-1, E-selectin, and IL-8 at the mRNA level, and inhibit the TNF-α-induced nuclear translocation of p65.


Assuntos
Hypocreales , Policetídeos , NF-kappa B/metabolismo , Policetídeos/química , Estrutura Molecular , Hypocreales/metabolismo , Transdução de Sinais
4.
J Hazard Mater ; 436: 129147, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35643000

RESUMO

Microbial remediation of heavy metals in soil has been widely studied. However, bioremediation efficiency is limited in practical applications because of nutritional deficiency, low efficiency, and competition with indigenous microorganisms. Herein, we prepared a biochar-based microbial agent (BMA) by immobilizing the microbial agent (MA, containing Bacillus subtilis, Bacillus cereus, and Citrobacter sp.) on biochar for the remediation of U and Cd in soil. The results showed that BMA increased soil organic matter, cation exchange capacity, and fluorescein diacetate hydrolysis activity and dehydrogenase activity by 58.7%, 38.2%, 42.9%, and 51.1%. The availability of U and Cd were significantly decreased by 67.4% and 54.2% in BMA amended soil, thereby reducing their accumulation in vegetables. BMA greatly promoted vegetable growth. Additionally, BMA significantly altered the structure and function of rhizosphere soil microbial communities. Coincidently, more abundant ecologically beneficial bacteria like Nitrospira, Nitrosomonas, Lysobacter, and Bacillus were observed, whereas plant pathogenic fungi like Fusarium and Alternaria reduced in BMA amended soil. The network analysis revealed that BMA amendment increased the tightness and complexity of microbial communities. Importantly, the compatibility of niches and microbial species within co-occurrence network was enhanced after BMA addition. These findings provide a promising strategy for suppressing heavy metal accumulation in vegetables and promoting their growth.


Assuntos
Metais Pesados , Poluentes do Solo , Bactérias , Cádmio/análise , Carvão Vegetal , Metais Pesados/análise , Rizosfera , Solo/química , Poluentes do Solo/análise , Verduras
5.
Phytochemistry ; 200: 113180, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35427653

RESUMO

Three undescribed meroterpenoids, named bipolacochlioquinones A-C, together with seven known compounds, were isolated from the plant endophytic fungus Bipolaris victoriae S27 derived from the fresh stems of Rubia podantha Diels. Their structures were mainly determined by extensive spectroscopic analysis. The relative configurations of bipolacochlioquinones A-C were assigned using the ROESY spectrum, comparison of their spectral data with that reported in the literatures, and NMR calculations. Moreover, their complete absolute configurations were further established by electronic circular dichroism calculations using density functional theory. Among them, bipolacochlioquinone A is found to represent the first example of previously undescribed 6/6/6/6/6 pentacyclic dioxane-containing cochlioquinones, and bipolacochlioquinone B possesses a rare 6/6/6/6/5 pentacyclic system bearing a tetrahydrofuran ring fused to a polyketide and a sesquiterpenoid subunit. All compounds were evaluated for their inhibitory effects on tumor growth, metastasis, and the NF-κB signaling pathway. Among them, bipolacochlioquinone C and cochlioquinone A show the most potent cytotoxicities and NF-κB inhibitory activities. The effects of bipolacochlioquinone C and cochlioquinone A on the expression of NF-κB-associated proteins were also evaluated using western blotting. These results indicate that bipolacochlioquinone C and cochlioquinone A can inhibit the growth and metastasis of HCT116 and MDA-MB-231 cells by suppressing the NF-κB signaling pathway.


Assuntos
Neoplasias , Rubia , Terpenos , Bipolaris , Linhagem Celular Tumoral , Humanos , NF-kappa B/metabolismo , Metástase Neoplásica , Rubia/química , Transdução de Sinais , Terpenos/farmacologia
6.
PLoS One ; 16(7): e0254134, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197556

RESUMO

A reliable, remote, and continuous real-time respiratory sound monitor with automated respiratory sound analysis ability is urgently required in many clinical scenarios-such as in monitoring disease progression of coronavirus disease 2019-to replace conventional auscultation with a handheld stethoscope. However, a robust computerized respiratory sound analysis algorithm for breath phase detection and adventitious sound detection at the recording level has not yet been validated in practical applications. In this study, we developed a lung sound database (HF_Lung_V1) comprising 9,765 audio files of lung sounds (duration of 15 s each), 34,095 inhalation labels, 18,349 exhalation labels, 13,883 continuous adventitious sound (CAS) labels (comprising 8,457 wheeze labels, 686 stridor labels, and 4,740 rhonchus labels), and 15,606 discontinuous adventitious sound labels (all crackles). We conducted benchmark tests using long short-term memory (LSTM), gated recurrent unit (GRU), bidirectional LSTM (BiLSTM), bidirectional GRU (BiGRU), convolutional neural network (CNN)-LSTM, CNN-GRU, CNN-BiLSTM, and CNN-BiGRU models for breath phase detection and adventitious sound detection. We also conducted a performance comparison between the LSTM-based and GRU-based models, between unidirectional and bidirectional models, and between models with and without a CNN. The results revealed that these models exhibited adequate performance in lung sound analysis. The GRU-based models outperformed, in terms of F1 scores and areas under the receiver operating characteristic curves, the LSTM-based models in most of the defined tasks. Furthermore, all bidirectional models outperformed their unidirectional counterparts. Finally, the addition of a CNN improved the accuracy of lung sound analysis, especially in the CAS detection tasks.


Assuntos
COVID-19/fisiopatologia , Pulmão/fisiopatologia , Sons Respiratórios/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Benchmarking , COVID-19/diagnóstico , Bases de Dados Factuais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Respiração
7.
J Clin Monit Comput ; 35(3): 663-670, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32388652

RESUMO

A 67-year-old male patient with chronic obstructive pulmonary disease was admitted to a hospital in northern Taiwan for progressive dyspnea and productive cough with an enlarged left upper lobe tumor (5.3 × 6.8 × 3.9 cm3). Previous chest auscultation on outpatient visits had yielded diffuse wheezes. A localized stridor (fundamental frequency of 125 Hz) was captured using a multichannel electronic stethoscope comprising four microelectromechanical system microphones. An energy-based localization algorithm was used to successfully locate the sound source of the stridor caused by tumor compression. The results of the algorithm were compatible with the findings obtained from computed tomography and bronchoscopy (mean radius = 9.40 mm and radial standard deviation = 14.97 mm). We demonstrated a potential diagnostic aid for pulmonary diseases through sound-source localization technology based on respiratory monitoring. The proposed technique can facilitate detection when advanced imaging tools are not immediately available. Continuing effort on the development of more precise estimation is warranted.


Assuntos
Neoplasias , Sons Respiratórios , Idoso , Auscultação , Eletrônica , Humanos , Pulmão , Masculino , Sons Respiratórios/etiologia
8.
J Hazard Mater ; 404(Pt A): 124151, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33032091

RESUMO

Premna microphylla turcz leaves (PMTL) is a resource-rich, biodegradable, renewable biomass. Here, a microsphere adsorbent was prepared from PMTL by a self-crosslinking method without any addition of chemical cross-linking agent, and characterized by SEM, FTIR, and XPS. The influence of preparation methods and conditions on the properties of the microspheres was studied and the self-crosslinking mechanism was analyzed. The effects of temperature, pH, contact time, uranium concentration, and adsorbent dosage on its adsorption performance toward to uranium were systematically explored. The results showed that PMTL endogenous pectin binding with endogenous Ca2+, Mg2+ and other metal ions to form an 'egg box' structure might be the mechanism of its self-crosslinking to form microspheres. The adsorption isotherms fitted well by the Freundlich model and the experimental maximum adsorption capacity of microspheres was 346.65 mg·g-1 at pH of 5, and kinetics data correlated well with the pseudo-second order model. The adsorption mechanism might be the coordination bonding between the uranium and oxygen-containing groups (hydroxyl and carboxyl groups), and the ion exchange between the uranium and metal ions (mainly Ca2+ and Mg2+). The PMTL microspheres are promising in treating uranium-containing wastewater in a more cost-effective and environmentally friendly manner.


Assuntos
Urânio , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Microesferas , Folhas de Planta
9.
J Hazard Mater ; 401: 123823, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33113745

RESUMO

This research explored the effect of biochar pyrolyzed from five different materials on U and Cd immobilization in soil. The results showed that all biochars improved the soil properties and microbial metabolic activities, and effectively immobilized U and Cd, especially corn stalk biochar. Subsequently, three strains Bacillus subtilis, Bacillus cereus, and Citrobacter sp. were mixed in a 3:3:2 proportion as a kind of mixed bacteria (MB9) that could adsorb U and Cd effectively. Two types of MB9-loaded biochar were synthesized by physical adsorption and sodium alginate embed method and referred to as AIB and EIB, respectively. MB9-loaded biochar showed superior U and Cd immobilization performance. At 75 d, the highest reduction in the DTPA- extractable U and Cd (69 % and 56 %) was achieved with the 3% AIB amendment. Additionally, compared to the addition of biochar or MB9 alone, AIB was more effective in promoting celery growth and reducing U and Cd accumulation. Finally, the microbial community structure analysis suggested that the relative abundance of Citrobacter genus and Bacillus genus was significantly increased, suggesting that the mixed bacteria MB9 was successfully colonized. These findings may provide a feasible technology for green and cost-effective remediation of heavy metal contamination in farmland soil.


Assuntos
Poluentes do Solo , Urânio , Bactérias , Cádmio/análise , Carvão Vegetal , Solo , Poluentes do Solo/análise
10.
Environ Int ; 144: 106051, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32889480

RESUMO

Post phytoremediation accumulation of heavy metals in plants is causing an environmental issue worldwide. In this study, we investigated the ability of eight different kinds of microorganisms to degrade and release heavy metals from heavy metal enriched ryegrass, including 5 species of bacteria (Bacillus subtilis, Bacillus licheniformis, Bacillus pumilus-I, Bacillus pumilus-II and Bacillus cereus) and 3 of fungi (Phanerochaete chrysosporium, Trichoderma ressei and Pterula sp. strain QD-1), by growing them under uranium stress and assessing their ability to degrade biomass. After 30 days, the degradation ability of fungi was found better than that of bacteria, while the metal leaching ability of bacteria was found better. The highest degradation rate (upto 60%) was obtained by using P. chrysosporium, Pterula sp. strain QD-1 exhibited the best leaching rate for uranium (upto 77%). The overall degradation rate of lignin and cellulose and hemicellulose was found lower (40% and 60%, respectively). According to the antagonistic characteristics of microbes, we combined different dominant species, in which under optimal conditions the T2 combination (P. chrysosporium, T. reesei, and Pterula sp. strain QD-1 and B. subtilis) was able to degrade 80% of the ryegrass, 51% of lignin, 74% of cellulose and hemicellulose, releasing 78% of U, 90% of Pb and the releasing rate of other heavy metals was more than 95%. FTIR analysis showed the least degradation of lignin, while SEM-EDX analysis of the degradation residues displayed the microstructure of ryegrass being greatly damaged. Only a small amount of U was found in the residues of the researched combinations. This study provides efficient Microbial Combined Degradation Technology for heavy metal enriched biomass, which can effectively deal with heavy metal enriched plants, and provide a basis for the recovery and utilization of heavy metals, avoiding secondary pollution in the environment caused by this type of biomass.


Assuntos
Lolium , Metais Pesados , Poluentes do Solo , Urânio , Biodegradação Ambiental , Metais Pesados/análise , Solo , Poluentes do Solo/análise , Tecnologia
11.
Orthop Surg ; 12(4): 1212-1222, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32725701

RESUMO

OBJECTIVE: To compare the clinical efficacy and safety of a personalized three-dimensional (3D) printed dynamic anterior plate-screw system for the quadrilateral area (DAPSQ) titanium plate and a traditional DAPSQ reconstruction plate in the treatment of double-column acetabular fractures. METHODS: This was a retrospective case-control study. From May 2014 to January 2018, 43 patients with double-column acetabular fractures underwent open reduction and internal fixation. Among these, 20 cases were fixed with a 3D printed DAPSQ plate (3D printed group) and 23 cases were fixed with a DAPSQ reconstruction plate (control group). The 3D printed group comprised 15 men and 5 women, with an average age of 50.1 ± 8.2 years. The control group comprised 16 men and 7 women, with an average age of 51.0 ± 8.6 years. The evaluation index included the surgical data (i.e. blood loss, operating time, duration of hospital stay, and intraoperative and postoperative complications), position and length of implants, reduction quality, hip function, and related complications. The reduction quality was evaluated using the Matta scoring standard and hip function was evaluated using the modified Merle d'Aubigné score. RESULTS: A total of 43 patients met the inclusion criteria. The mean postoperative follow up was 35.2 months in the 3D printed group and 36.9 months in the control group. There were no significant group differences in demographic data between the two groups. The position and length of the 3D printed implants were generally in accord with preoperative planning using a 3D pelvic model. Patients in the 3D printed group had significantly shorter operation time (223.2 vs 260.5 min, P < 0.05) and less intraoperative blood loss (930.4 vs 1426.1 mL, P < 0.05) compared to the control group. Anatomic, imperfect, and poor reduction was obtained in 13, 5, and 2 cases in the 3D printed group, respectively, and was obtained in 12, 8, and 3 cases in the control group. The modified Merle d'Aubigné scores were excellent in 11 cases, good in seven cases, and fair in two cases in the 3D printed group. They were excellent in 11 cases, good in eight cases, fair in three cases, and poor in one case in the control group. The reduction quality and hip function did not differ within the groups (P > 0.05). The general complication rate in the 3D printed group and the control group was 15% and 26.1%, respectively, but the difference between the two groups was not statistically significant. CONCLUSION: Use of a personalized 3D printed DAPSQ plate has potential advantages in reducing the operation time and blood loss during the treatment of double-column acetabular fractures.


Assuntos
Acetábulo/lesões , Acetábulo/cirurgia , Placas Ósseas , Desenho de Equipamento , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/cirurgia , Impressão Tridimensional , Adulto , Parafusos Ósseos , Estudos de Casos e Controles , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Titânio
12.
Int J Biol Macromol ; 145: 535-546, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31883902

RESUMO

Biosorbents have been a promising adsorbent to remove uranium while their poor mechanical properties prevent them from being widely used in practice. In this study, carboxymethyl konjac glucomannan (CMKGM) was incorporated to gellan gum to form a double-network gel micro spheres (CMKGM/GG-Al) for uranium removal with its mechanical strength fairly being reinforced. The compressive strength of the CMKGM/GG-Al microspheres was about 6 times than that of GG-Ca microspheres we prepared before while the adsorption capacity still be at a better value with the fitting maximum adsorption capacity being of 97.94 mg/g. Its uranium adsorption properties were investigated by considering the influence of pH, the adsorbent dosage, temperature, initial uranium concentration, time and coexisting ions. The adsorption mechanism was also investigated according to the SEM, EDX, FT-IR and XPS data analysis. The isotherm equilibrium data which were best fitted with Langmuir model and the kinetics data which were best fitted with pseudo-second-order model. It was inferred that the adsorption process was mainly the ion-exchange and the coordination with hydroxyl groups on the adsorbent surface and the adsorption process was endothermic and spontaneous. The CMKGM/GG-Al microspheres prepared in this study would be more conducive to practical application for uranium removal.


Assuntos
Mananas/química , Microesferas , Polissacarídeos Bacterianos/química , Urânio/química , Adsorção , Algoritmos , Fenômenos Químicos , Concentração de Íons de Hidrogênio , Íons , Cinética , Modelos Químicos , Análise Espectral , Propriedades de Superfície , Termodinâmica
13.
Water Res ; 165: 114975, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31430653

RESUMO

Electrolysis and permanganate (PM) oxidation are two commonly used technologies for water treatment. However, they are often handicapped by their slow reaction rates. To improve the removal efficiency of refractory contaminants, we combined electrolysis with PM using an activated carbon fiber (ACF) as cathode (E-ACF-PM) for the first time to treat diclofenac (DCF) in aqueous solution. Up to 90% DCF was removed in 5 min by E-ACF-PM process. In comparison, only 3.95 and 27.35% of DCF was removed by individual electrolysis and PM oxidation at the same time, respectively. Acidic condition was more conducive to DCF removal. Surprisingly, soluble Mn(III) (aq) formed on the surface of ACF was demonstrated as the principal oxidizing agent in E-ACF-PM process. Further studies showed that all three components (electrolysis + ACF + PM) were necessary to facilitate the heterogeneous generation of reactive Mn(III) (aq). Moreover, SEM images and XPS spectra of ACF before and after treatment revealed that the morphologies and elemental compositions of reacted ACF were nearly unchanged during the E-ACF-PM process. ACF can be remained active and utilized to the rapid degradation of DCF in E-ACF-PM process even after reused for 20 times. Therefore, the E-ACF-PM process may provide a novel and effective alternative on the generation of reactive Mn(III) (aq) in situ for water treatment by green electrochemical reactions.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Fibra de Carbono , Diclofenaco , Compostos de Manganês , Oxirredução , Óxidos
14.
Artigo em Chinês | MEDLINE | ID: mdl-31245943

RESUMO

OBJECTIVE: To study the effect of ß-sheet blocking peptide H102 on the expression of AMPK-mTOR autophagy pathway-related protein in APP/PS1 double transgenic AD mice. METHODS: Thirty male APP/PS1 transgenic male AD mice of 6 months old were randomly divided into AD group and H102 intervention group, and C57BL/6J male mice of the same age were used as control group (n=15). The mice in the HF group were administered with 5 µl (5.8 mg/kg) of H102 polypeptide solution through the nasal cavity at the same time period, and the mice in the control group and the AD group were given the same amount of blank adjuvant solution daily. The memory recognition ability was tested by a new object recognition experiment 30 days after continuous administration. Immunohistochemistry and Western blot were used to detect the expressions of phosphorylated AMP-activated protein kinase(P-AMPK),phosphorylated mammalian target of rapamycin (P-mTOR) and ratio of LC32to LC31(LC3II/I )in brain tissue. RESULTS: Compared with the control group, the new object recognition index (RI) of the AD group was significantly lower (P<0.05), and the P-AMPK and LC3II/I ratios in the brain of the mice were significantly lower (P<0.05). The expression of P-mTOR protein was increased significantly (P<0.05). Compared with the AD group, the RI of the H102 intervention group was increased significantly (P<0.05), and the P-AMPK and LC3II/I ratios in the brain tissue of the mice were increased significantly (P<0.05). The expression of P-mTOR protein was decreased significantly (P<0.05). CONCLUSION: H102 can improve the recognition and memory ability of AD mice by activating the AMPK-mTOR autophagy-related pathway.


Assuntos
Doença de Alzheimer , Autofagia , Memória , Peptídeos , Serina-Treonina Quinases TOR , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Precursor de Proteína beta-Amiloide , Animais , Autofagia/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Peptídeos/farmacologia , Distribuição Aleatória , Serina-Treonina Quinases TOR/efeitos dos fármacos
15.
RSC Adv ; 9(14): 8091-8103, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35521166

RESUMO

The extraction of uranium(vi) from seawater is of paramount interest to meet the rapid expansion of global energy needs. A novel gelatin/PVA composite nanofiber band loaded with bayberry tannin (GPNB-BT) was used to extract uranium(vi) from simulated seawater in this study. It was fabricated by electrostatic spinning and crosslinking, and characterized by SEM, EDX, FTIR, and XPS. Batch experiments were carried out to investigate the adsorption of uranium(vi) onto GPNB-BT. Simultaneously, the regeneration-reuse process of the GPNB-BT was determined and illustrated here. The GPNB-BT exhibited excellent adsorption and regeneration performance, and a maximum adsorption capacity of 254.8 mg g-1 toward uranium(vi) was obtained at 298.15 K, pH = 5.5. Further, the regeneration rate for uranium did not decrease significantly after five cycles. Moreover, even at an extremely low initial concentration of 3 µg L-1 in the simulated seawater for 24 h, GPNB-BT showed an ultrahigh adsorption rate of more than 90% and adsorption capacity of 7.2 µg g-1 for uranium. The high density of adjacent phenolic hydroxyl groups and the specific surface area of GPNB-BT improved the adsorption ability of GPNB-BT for uranium. Therefore, the GPNB-BT was shown to have an application prospect for the effective extraction of uranium(vi) from seawater.

16.
Front Chem ; 7: 877, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998681

RESUMO

In this work, grapheme oxide (GO) nano-sheets were synthesized and dispersed in the aqueous phase for the interfacial polymerization (IP) process to develop a new type of thin-film composite (TFC) membranes for forward osmosis (FO) applications. The effects of the GO concentrations on the membrane surfaces and cross-sectional morphologies and FO desalination performances of the as-prepared TFC membranes were investigated systematically. Compared with the control membrane, the optimal GO-incorporated TFC membrane displayed higher water flux, less specific reverse solute flux (SRSF) and lower structure parameter. Moreover, the optimized membrane showed 75.0 times higher chlorine resistance than the control membrane. In general, these new type of membranes could be an effective strategy to fabricate high-performance FO membranes with good desalination performance and chlorine resistance.

17.
Int J Biol Macromol ; 124: 418-428, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30496862

RESUMO

Widespread concern had been given raise to the pollution of antibiotics including tetracyclines in water environment in recent years. A novel Cu-immobilized alginate adsorbent had been synthesized successfully through a facile fabrication way called sol-gel method, and its adsorption performance had been investigated for the tetracycline removal at various conditions, including the pH, temperature, the dosage of adsorbent, concentration and contact time. The adsorbent was characterized with SEM, EDX, FT-IR and XPS analyses to confirm its properties before and after adsorption. The equilibrium data was fitted well with the Freundlich isotherm model and the maximum adsorption capacity for tetracycline was 53.26 mg·g-1 at pH 3, 318.15 K, and 90 mg·L-1 tetracycline solution. The pseudo-second-order kinetic and Freundlich isotherm models combining with the correlative analysis implied that the tetracycline adsorption onto the Cu-immobilized alginate adsorbent was administrated by the n-π electron-donor-acceptor interaction (n-π EDA interaction), hydrogen bond and the cation bonding bridge. Moreover, thermodynamic study demonstrated that the nature of tetracycline adsorption was endothermic, feasible and spontaneous. Compared with the other adsorbents, the as-prepared adsorbent had an excellent tetracycline adsorption capacity, and was expected to be widely applied in the adsorption treatment of tetracycline wastewater.


Assuntos
Alginatos/química , Cobre/química , Tetraciclina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Humanos , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica , Águas Residuárias/química
18.
Ecotoxicol Environ Saf ; 170: 9-17, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30508754

RESUMO

A novel gelatin/PVA composite nanofiber band loaded with bayberry tannin (GPNB-BT) was prepared by electrostatic spinning and crosslinking for extraction of uranium (VI) from simulated seawater. The influential factors of tannin loaded on the nanofiber band were investigated in detail. Surface morphology and fiber diameter of GPNB-BT were studied by Scanning Electron Microscopy (SEM). Functional groups of GPNB-BT were investigated by Fourier Transform Infrared Spectrometer (FTIR). The adsorption process and mechanism of uranium on GPNB-BT was characterized by Energy Dispersive X-ray (EDX) and X-ray Photoelectron Spectroscopy (XPS). The results revealed that the BT had been stably solidified on the GPNB. Compared with other tannin-immobilized membranes, the nano-network structure of GPNB-BT with 200-400 nm diameter of fibers can promote solidification of tannins and improve adsorption capacity of GPNB-BT for uranium. The maximum adsorption capacity of the GPNB-BT for uranium is 170 mg/g at the optimal pH of 5.5 in 80 mg/L of initial uranium concentration and 1.4 µg/g even at extremely low initial concentration of 3 µg/L in the simulated seawater for 24 h. The GPNB-BT with good hydraulic properties, floatability and adsorption capacity for uranium is expected to be widely used in separation and enrichment of uranium in seawater and radioactive waste water.


Assuntos
Gelatina/química , Nanofibras/química , Água do Mar/química , Taninos/química , Urânio/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Myrica/química , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Water Res ; 144: 145-161, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30025266

RESUMO

High-silica zeolites have been found to be effective adsorbents for the removal of organic micro-pollutants (OMPs) from impaired water, including various pharmaceuticals, personal care products, industrial chemicals, etc. In this review, the properties and fundamentals of high-silica zeolites are summarised. Recent research on mechanisms and efficiencies of OMP adsorption by high-silica zeolites are reviewed to assess the potential opportunities and challenges for the application of high-silica zeolites for OMP adsorption in water treatment. It is concluded that the adsorption capacities are well-related to surface hydrophobicity/hydrophilicity and structural features, e.g. micropore volume and pore size of high-silica zeolites, as well as the properties of OMPs. By using high-silica zeolites, the undesired competitive adsorption of background organic matter (BOM) in natural water could potentially be prevented. In addition, oxidative regeneration could be applied on-site to restore the adsorption capacity of zeolites for OMPs and prevent the toxic residues from re-entering the environment.


Assuntos
Poluentes Químicos da Água/química , Purificação da Água/métodos , Zeolitas/química , Adsorção , Compostos Orgânicos/química , Compostos Orgânicos/isolamento & purificação , Dióxido de Silício , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/instrumentação
20.
Front Neurosci ; 12: 935, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30618564

RESUMO

Background: Recent studies have shown that the patients with spinocerebellar ataxia type 3 (SCA3) may not only have disease involvement in the cerebellum and brainstem but also in the cerebral regions. However, the relations between the widespread degenerated brain regions remains incompletely explored. Methods: In the present study, we investigate the topological properties of the brain networks of SCA3 patients (n = 40) constructed based on the correlation of three-dimensional fractal dimension values. Random and targeted attacks were applied to measure the network resilience of normal and SCA3 groups. Results: The SCA3 networks had significantly smaller clustering coefficients (P < 0.05) and global efficiency (P < 0.05) but larger characteristic path length (P < 0.05) than the normal controls networks, implying loss of small-world features. Furthermore, the SCA3 patients were associated with reduced nodal betweenness (P < 0.001) in the left supplementary motor area, bilateral paracentral lobules, and right thalamus, indicating that the motor control circuit might be compromised. Conclusions: The SCA3 networks were more vulnerable to targeted attacks than the normal controls networks because of the effects of pathological topological organization. The SCA3 revealed a more sparsity and disrupted structural network with decreased values in the largest component size, mean degree, mean density, clustering coefficient, and global efficiency and increased value in characteristic path length. The cortico-cerebral circuits in SCA3 were disrupted and segregated into occipital-parietal (visual-spatial cognition) and frontal-pre-frontal (motor control) clusters. The cerebellum of SCA3 were segregated from cerebellum-temporal-frontal circuits and clustered into a frontal-temporal cluster (cognitive control). Therefore, the disrupted structural network presented in this study might reflect the clinical characteristics of SCA3.

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