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1.
Environ Sci Technol ; 53(24): 14752-14760, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31747513

RESUMO

The treatment of spent cooking liquor is critical for clean production of pulp and paper industry. There is a compelling need to develop a cost-effective and green technology for reuse of organic matter in spent cooking liquor to mitigate the negative impacts on the environment. The objective of this study is to examine the chemical structure of fulvic acid-like substances extracted from spent cooking liquor (PFA) and their relationship with bioactivity in plant growth. Compared with the benchmark Pahokee peat fulvic acid (PPFA), PFA has less aromatic structure, but higher content of lignin, carbohydrates, and amino acid. After fractionation, protein/amino proportion decreased with increasing molecular weight, but the aromaticity increased. Under salt stress, rice seedling growth was promoted by PFA with low molecular weight (<5 kDa), but inhibited by fraction with high molecular weight (>10 kDa). Principal component analysis suggested that promoted growth was more related with chemical structure (O- and N-alkyl moieties) than with molecular weight. This study provided the theoretical basis for development of an innovative green technology of sustainable reuse of spent cooking liquor in agriculture.


Assuntos
Benzopiranos , Lignina , Carboidratos , Culinária
2.
Int J Biol Macromol ; 267(Pt 1): 131471, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599419

RESUMO

The conversion of glucose into fructose can transform cellulose into high-value chemicals. This study introduces an innovative synthesis method for creating an MgO-based ordered mesoporous carbon (MgO@OMC) catalyst, aimed at the efficient isomerization of glucose into fructose. Throughout the synthesis process, lignin serves as the exclusive carbon precursor, while Mg2+ functions as both a crosslinking agent and a metallic active center. This enables a one-step synthesis of MgO@OMC via a solvent-induced evaporation self-assembly (EISA) method. The synthesized MgO@OMCs exhibit an impeccable 2D hexagonal ordered mesoporous structure, in addition to a substantial specific surface area (378.2 m2/g) and small MgO nanoparticles (1.52 nm). Furthermore, this catalyst was shown active, selective, and reusable in the isomerization of glucose to fructose. It yields 41 % fructose with a selectivity of up to 89.3 % at a significant glucose loading of 7 wt% in aqueous solution over MgO0.5@OMC-600. This performance closely rivals the current maximum glucose isomerization yield achieved with solid base catalysts. Additionally, the catalyst retains a fructose selectivity above 60 % even after 4 cycles, a feature attributable to its extended ordered mesoporous structure and the spatial confinement effect of the OMCs, bestowing it with high catalytic efficiency.


Assuntos
Carbono , Frutose , Glucose , Lignina , Óxido de Magnésio , Frutose/química , Lignina/química , Glucose/química , Carbono/química , Porosidade , Óxido de Magnésio/química , Catálise , Isomerismo
3.
Nat Commun ; 14(1): 3890, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37393327

RESUMO

Solid polymer electrolytes (SPEs) and hydrogel electrolytes were developed as electrolytes for zinc ion batteries (ZIBs). Hydrogels can retain water molecules and provide high ionic conductivities; however, they contain many free water molecules, inevitably causing side reactions on the zinc anode. SPEs can enhance the stability of anodes, but they typically possess low ionic conductivities and result in high impedance. Here, we develop a lean water hydrogel electrolyte, aiming to balance ion transfer, anode stability, electrochemical stability window and resistance. This hydrogel is equipped with a molecular lubrication mechanism to ensure fast ion transportation. Additionally, this design leads to a widened electrochemical stability window and highly reversible zinc plating/ stripping. The full cell shows excellent cycling stability and capacity retentions at high and low current rates, respectively. Moreover, superior adhesion ability can be achieved, meeting the needs of flexible devices.


Assuntos
Hidrogéis , Zinco , Eletrólitos , Íons , Polímeros , Água
4.
Int J Biol Macromol ; 187: 232-239, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34314791

RESUMO

Sulfonated lignin-derived ordered mesoporous carbon (OMC-SO3H) solid acid was synthesized through solvent evaporation induced self-assembly (EISA) method followed by sulfonation, using lignin as carbon precursor and glyoxal as cross-linking agent during the preparation process. The as-synthesized OMC-SO3H exhibited a typical 2D hexagonal meso-structure (space group p6mm) and showed a good catalytic performance for the catalytic conversion of hemicellulose-derived xylose to furfural. A highest furfural yield of 76.7% with 100% xylose conversion was achieved at 200 °C for 45 min in γ-valerolactone (GVL)-water (85:15 v/v%) mixture. The lignin-derived OMC-SO3H solid acid catalyst showed superior stability and reusability, and was also applicable to the catalytic production of furfural from xylan. This work provides a promising strategy for the synthesis of ordered mesoporous carbon solid acid from green and sustainable lignin biomass resource, which has wide range of applications in the utilization of cellulose and hemicellulose.


Assuntos
Carbono/química , Furaldeído/química , Lignina/química , Ácidos Sulfônicos/química , Xilose/química , Biomassa , Catálise , Porosidade , Solventes/química , Propriedades de Superfície , Temperatura , Fatores de Tempo
5.
Quant Imaging Med Surg ; 11(6): 2279-2291, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34079701

RESUMO

BACKGROUND: The feasibility and image quality of three-dimensional (3D) amide proton transfer (APT)-weighted (APTw) in parotid tumor lesions have not been well established in previous studies. This study aimed to evaluate the utility of APT imaging in parotid lesions and glands. METHODS: Patients with parotid lesions received 3D turbo spin echo (TSE) APTw on a 3.0T scanner. Two radiologists, who were blinded to the clinical data, independently evaluated the APTw image quality using 4-point Likert scales (1= poor, 4= excellent) in terms of integrity and hyperintensity artifacts. An image quality selection protocol was built based on the two scores. Evaluable images (integrity score >1) and trustable images (integrity score >3 and hyperintensity artifacts score >2) were then enrolled for APTw value comparison between parotid lesions and glands. RESULTS: Forty consecutive patients were included in this study. Four patients were excluded due to severe motion (n=3) or dental (n=1) artifacts, and 36 patients received the APT sequence. Among these, more parotid tumor lesions (34/36, 94.4%) than normal parotid glands (23/31, 74.2%) revealed excellent integrity scores (score =4) (P=0.034). Most parotid tumor lesions (24/34, 70.6%) and glands (16/28, 57.1%) revealed no or little hyperintensity artifacts for diagnosis (scores 3 and 4). APT values of parotid lesions and glands in the evaluable groups were 2.11%±1.15% and 1.60%±1.56%, respectively, and the difference was not significant (P=0.197). APT values of parotid lesions and glands in the trustable groups were 1.99%±1.18% and 1.03%±1.09%, respectively, and the difference was statistically significant (P=0.018). CONCLUSIONS: 3D APTw could be used to differentiate parotid tumors and normal parotid glands; however, the technology still needs to be improved to remove artifacts. In our study, most APTw images of tumor lesions in parotid glands had acceptable image quality, and these APTw images are feasible for diagnostic use.

6.
Talanta ; 198: 86-92, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30876607

RESUMO

In this work, a thin film PET based gold electrode (PGE) glucose sensor was fabricated through ultraviolet mediated chemical plating technique. Compared with the most existing wearable thin film gold electrode sensors, the PGE-glucose sensor is simple, low cost and minimum instrumentation was required. The proposed glucose sensor revealed a sensitivity of 22.05 µA mM-1 cm-2 in a linear range from 0.02 to 1.11 mM with a low detection limit of 2.7 µM (S/N = 3). The PGE-glucose sensor had a good selectivity and was not interfered by lactic acid, urea, acetaminophen, uric acid, dopamine and ascorbic acid. Additionally, it exhibited good reproducibility and long-term stability over four weeks. Finally, the disposable PGE-glucose sensor was successfully applied to determine the glucose in sweat and commercial beverage accurately.


Assuntos
Técnicas Eletroquímicas , Glucose/análise , Ouro/química , Polietilenotereftalatos/química , Suor/química , Eletrodos , Tamanho da Partícula , Propriedades de Superfície
7.
Nat Commun ; 10(1): 4204, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527592

RESUMO

Metal-organic frameworks (MOFs) with high porosity and designable functionality make it possible to access the merits of high permeability and selectivity. However, scalable fabrication methods to produce mixed matrix membranes (MMMs) with good flexibility and ultrahigh MOF loading are urgently needed yet largely unmet. Herein, we report a thermally induced phase separation-hot pressing (TIPS-HoP) strategy to roll-to-roll produce 10 distinct MOF-membranes (loadings up to 86 wt%). Ultrahigh-molecular-weight polyethylene interweaving the MOF particles contributes to their mechanical strength. Rejections (99%) of organic dyes with a water flux of 125.7 L m-2 h-1 bar-1 under cross-flow filtration mode. The micron-sized channels between the MOF particles translate into fast water permeation, while the porous MOFs reject solutes through rapid adsorption. This strategy paves ways for developing high-performance membrane adsorbers for crucial separation processes. As a proof-of-concept, the abilities of the membrane adsorbers for separating racemates and proteins have been demonstrated.


Assuntos
Estruturas Metalorgânicas/química , Adsorção , Membranas Artificiais , Porosidade , Proteínas/isolamento & purificação , Propriedades de Superfície
8.
J Hazard Mater ; 378: 120702, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202064

RESUMO

Increasing environmental concerns about organic waste in paper mill effluents demand alternative wastewater management technology. We reported novel activation of fulvic acid-like in paper mill effluents using hydrogen peroxide (H2O2) as oxidizer and titanium oxide (TiO2) as catalyst. Spectroscopic characteristics of fulvic acid-like in paper mill effluents before and after activation (PFA and PFA-Os, respectively) were compared with a benchmark fulvic acid extracted from leonardite (LFA). Results indicated that PFA-Os exhibited less lignin structures, more functional groups and lower molecular weight than PFA, sharing much similarity with LFA. Among PFA-Os with varying degrees of oxidation, PFA-O-3 activated with 1:2 vol ratio of paper mill effluent and 30% H2O2 for 20 min digestion at 90 °C stands out to be the optimal for further examination of its biological activity. Bioassays with rice seed/seedling indicated that applications of LFA at 2-5 mg-C/L and PFA-O-3 at 60-100 mg-C/L significantly increased rice seed germination rate and seedling growth under salt stress imposed with 100 mM NaCl. The mechanism was mainly through reduced oxidative damage via activation of antioxidative enzymes and lipid peroxidation. This study provides the needed technical basis of safer and cleaner technologies for innovative management of paper mill effluents.


Assuntos
Benzopiranos/química , Peróxido de Hidrogênio/química , Resíduos Industriais/análise , Papel , Estresse Salino , Titânio/química , Catálise , Germinação , Lignina/química , Minerais/química , Oryza/química , Oxirredução , Sais/química , Plântula , Eliminação de Resíduos Líquidos , Águas Residuárias
9.
ACS Nano ; 12(6): 5417-5426, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29869497

RESUMO

Ischemic stroke is a leading cause of long-term disability and death worldwide. Current drug delivery vehicles for the treatment of ischemic stroke are less than satisfactory, in large part due to their short circulation lives, lack of specific targeting to the ischemic site, and poor controllability of drug release. In light of the upregulation of reactive oxygen species (ROS) in the ischemic neuron, we herein developed a bioengineered ROS-responsive nanocarrier for stroke-specific delivery of a neuroprotective agent, NR2B9C, against ischemic brain damage. The nanocarrier is composed of a dextran polymer core modified with ROS-responsive boronic ester and a red blood cell (RBC) membrane shell with stroke homing peptide (SHp) inserted. These targeted "core-shell" nanoparticles (designated as SHp-RBC-NP) could thus have controlled release of NR2B9C triggered by high intracellular ROS in ischemic neurons after homing to ischemic brain tissues. The potential of the SHp-RBC-NP for ischemic stroke therapy was systematically evaluated in vitro and in rat models of middle cerebral artery occlusion (MCAO). In vitro results showed that the SHp-RBC-NP had great protective effects on glutamate-induced cytotoxicity in PC-12 cells. In vivo pharmacokinetic (PK) and pharmacodynamic (PD) testing further demonstrated that the bioengineered nanoparticles can drastically prolong the systemic circulation of NR2B9C, enhance the active targeting of the ischemic area in the MCAO rats, and reduce ischemic brain damage.


Assuntos
Ácidos Borônicos/química , Isquemia Encefálica/tratamento farmacológico , Dextranos/farmacologia , Portadores de Fármacos/química , Ésteres/química , Fármacos Neuroprotetores/farmacologia , Espécies Reativas de Oxigênio/química , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Isquemia Encefálica/metabolismo , Dextranos/química , Portadores de Fármacos/farmacologia , Masculino , Nanopartículas/química , Fármacos Neuroprotetores/química , Células PC12 , Tamanho da Partícula , Polímeros/química , Polímeros/farmacologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Acidente Vascular Cerebral/metabolismo , Propriedades de Superfície
10.
Adv Healthc Mater ; 3(10): 1597-607, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24668927

RESUMO

Non-invasive, biomedical devices have the potential to provide important, quantitative data for the assessment of skin diseases and wound healing. Traditional methods either rely on qualitative visual and tactile judgments of a professional and/or data obtained using instrumentation with forms that do not readily allow intimate integration with sensitive skin near a wound site. Here, an electronic sensor platform that can softly and reversibly laminate perilesionally at wounds to provide highly accurate, quantitative data of relevance to the management of surgical wound healing is reported. Clinical studies on patients using thermal sensors and actuators in fractal layouts provide precise time-dependent mapping of temperature and thermal conductivity of the skin near the wounds. Analytical and simulation results establish the fundamentals of the sensing modalities, the mechanics of the system, and strategies for optimized design. The use of this type of "epidermal" electronics system in a realistic clinical setting with human subjects establishes a set of practical procedures in disinfection, reuse, and protocols for quantitative measurement. The results have the potential to address important unmet needs in chronic wound management.


Assuntos
Eletrônica Médica/instrumentação , Monitorização Fisiológica/instrumentação , Cicatrização/fisiologia , Idoso , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Silicones , Temperatura Cutânea/fisiologia , Fita Cirúrgica , Termografia/instrumentação
11.
J Biomater Sci Polym Ed ; 24(12): 1472-83, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23829459

RESUMO

Human hepatocellular carcinoma (HCC) is one of the major causes of death worldwide. To investigate the relative importance of active and passive targeting strategies, the synthesis, characterization, in vitro uptake, and in vivo biodistribution of specific sulfapyridine HPMA (HPMA: N-(2-hydroxypropyl methacrylamide)) copolymer (sulfapyridine: SPD) conjugates, nonspecific HPMA copolymer conjugates, and DTPA are described in this study. The poly(HPMA)-SPD-DTPA (DTPA: diethylenetriaminepentaacetic acid), poly(HPMA)-DTPA, and DTPA conjugates were radiolabeled with the radionuclide (99m)Tc and tested for uptake by cultured H22 cells. The cellular accumulation of poly(HPMA)-SPD-DTPA-(99m)Tc complex was found to be time-dependent. The poly(HPMA)-SPD-DTPA-(99m)Tc tracer exhibited rapid uptake kinetics in cell culture with a t(1/2) of ~5 min. The uptake of poly(HPMA)-SPD-DTPA-(99m)Tc was significantly higher than that of poly(HPMA)-DTPA-(99m)Tc, indicating that the uptake of the poly(HPMA)-SPD-DTPA-(99m)T was active binding. The uptake of poly(HPMA)-DTPA-(99m)Tc was significantly higher than that of DTPA-(99m)Tc, suggesting that the uptake of the poly(HPMA)-DTPA-(99m)T was passive binding. Twenty-four hour necropsy data in the hepatocellular carcinoma tumor model showed significantly higher (p < 0.001) tumor localization for poly(HPMA)-SPD-DTPA-(99m)Tc (4.98 ± 0.48%ID/g [percentage injected dose per gram tissue]) compared with poly(HPMA)-DTPA-(99m)Tc (2.69 ± 0.15% ID/g) and DTPA-(99m)Tc (0.83 ± 0.03%ID/g). Moreover, higher T/B for poly(HPMA)-SPD-DTPA-(99m)Tc indicated reduced extravazation of the targeted polymeric conjugates in normal tissues. Specific molecular targeting and nonspecific vascular permeability are both significant in the relative tumor localization of poly(HPMA)-SPD-DTPA-(99m)Tc. Extravascular leak in nonspecific organs appears to be a major factor in reducing the T/B for the sulfapyridine molecules. Thus, the poly(HPMA)-SPD-DTPA is expected to be used as the potential macromolecular targeting carrier for hepatoma carcinoma in mice.


Assuntos
Acrilamidas/síntese química , Ácido Pentético/análogos & derivados , Ácidos Polimetacrílicos/síntese química , Ácidos Polimetacrílicos/farmacocinética , Compostos Radiofarmacêuticos/síntese química , Acrilamidas/química , Acrilamidas/farmacocinética , Animais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Transplante de Neoplasias , Ácido Pentético/síntese química , Ácido Pentético/química , Ácido Pentético/farmacocinética , Ácidos Polimetacrílicos/química , Cintilografia , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Tecnécio , Distribuição Tecidual
12.
Ai Zheng ; 24(4): 488-93, 2005 Apr.
Artigo em Zh | MEDLINE | ID: mdl-15820076

RESUMO

BACKGROUND & OBJECTIVE: Vertebral metastasis is a common manifestation of patients with advanced cancer without effective treatment. This study was to explore treatment value and efficacy of percutaneous vertebroplasty (PVP) combined with interventional chemotherapy on vertebral metastases. METHODS: Seventy-five patients with vertebral metastases (42 men, 33 women; aged 31-76 years) were divided into 2 groups: 39 were treated by PVP combined with chemotherapy (VPCC group), and 36 were treated by PVP alone (VP group). All procedures were guided by CT scan. The results and complications were evaluated by pain questionnaire and routine follow-up. RESULTS: Response rate was significantly higher in VPCC group than in VP group (93.0% vs. 74.4%, P < 0.05); complete response rates of VPCC group and VP group were 25.6% and 10.3%. Common complication of VPCC was transient aggravation of pain. CONCLUSIONS: PVP may release the pain, and consolidate the vertebrae of patients with vertebral metastases. Its short-term effect may be enhanced by adding drugs into bone cement.


Assuntos
Cimentos Ósseos/uso terapêutico , Vértebras Lombares , Procedimentos Ortopédicos/métodos , Neoplasias da Coluna Vertebral , Vértebras Torácicas , Adulto , Idoso , Neoplasias da Mama/patologia , Terapia Combinada , Epirubicina/uso terapêutico , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Medição da Dor , Radiografia Intervencionista , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/tratamento farmacológico , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/cirurgia
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