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1.
Anal Chem ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39233361

RESUMO

The enzymatic depolymerization is a promising route to valorize the lignin polymers by turning the cross-linked polymers into monomers or oligomers. However, the lignin polymers cannot be effectively converted into small chemicals, as the oligomers are prone to polymerization, which is particularly challenging to monitor and thus regulate. Here, we develop a microstructured fiber Bragg grating (mFBG) sensor to probe the dynamic polymerization process of typical lignin oligomer surrogates─guaiacol (monomer) and guaiacylglycerol-ß-guaiacyl ether (GBG, dimer)─catalyzed by laccase in an operando way. The mFBG sensor was developed with its reliability well validated by control experiments at first. Further, operando monitoring of the polymerization reaction process of the typical lignin monomer (i.e., guaiacol) and dimer (guaiacylglycerol-ß-guaiacyl ether, GBG) was demonstrated under various conditions with the mFBG sensor. The GC-MS and UV-vis absorption measurements were carried out as a further check. Finally, the specific polymerization characteristics and reaction mechanism were studied. The mFBG sensor enables operando monitoring of the heterogeneous polymerization process of lignin monomers and oligomers and can potentially be tailored to probe more complex lignin depolymerization processes and unveil enzymatic synergistic mechanisms for the biological transition of biomass.

2.
Environ Res ; 256: 119245, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810821

RESUMO

Microalgae have been renowned as the most promising energy organism with significant potential in carbon fixation. In the large-scale cultivation of microalgae, the 3D porous substrate with higher specific surface area is favorable to microalgae adsorption and biofilm formation, whereas difficult for biofilm detachment and microalgae harvesting. To solve this contradiction, N-isopropylacrylamide, a temperature-responsive gels material, was grafted onto the inner surface of the 3D porous substrate to form temperature-controllable interface wettability. The interfacial free energy between microalgae biofilm and the substrates increased from -63.02 mJ/m2 to -31.89 mJ/m2 when temperature was lowered from 32 °C to 17 °C, weakening the adsorption capacity of cells to the surface, and making the biofilm detachment ratio increased to 50.8%. When further cooling the environmental temperature to 4 °C, the detachment capability of microalgae biofilm kept growing. 91.6% of the cells in the biofilm were harvesting from the 3D porous substrate. And the biofilm detached rate was up to 19.84 g/m2/h, realizing the temperature-controlled microalgae biofilm harvesting. But, microalgae growth results in the secretion of extracellular polymeric substances (EPS), which enhanced biofilm adhesion and made cell detachment more difficult. Thus, ultrasonic vibration was used to reinforce biofilm detachment. With the help of ultrasonic vibration, microalgae biofilm detached rate increased by 143.45% to 41.07 g/m2/h. These findings provide a solid foundation for further development of microalgae biofilm detachment and harvesting technology.


Assuntos
Biofilmes , Géis , Microalgas , Temperatura , Biofilmes/crescimento & desenvolvimento , Microalgas/crescimento & desenvolvimento , Porosidade , Géis/química , Acrilamidas/química
3.
Environ Res ; 216(Pt 3): 114645, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36323351

RESUMO

Microalgae biofilm-based culture provides an efficient CO2 reduction and wastewater treatment method for its high photosynthetic efficiency and density. As supporting substrates for microalgae biofilm, porous materials have a big available adsorption area, but mutual shading makes it difficult to transmit external light to the internal surface for attached cells' photosynthesis. Thus, light-guided particles (SiO2) were introduced into photosensitive resin to fabricate a light-guided ordered porous photobioreactor (PBR) by 3D printing technology in this study. The space utilization of the PBR was significantly enhanced and the effective microalgae adsorption area was increased by 13.6 times. Further, a thermo-responsive hydrogel was grafted onto the surface of the substrate to form a smart temperature-controllable interface that could enhance microalgae adsorption and desorption in both directions. When the thermo-responsive layer received light, it would generate heat due to the hydrogel's photo-thermal effect. And the surface temperature would then raise to 33 °C, higher than the hydrogel phase transition point of 32 °C, making the surface shrinking and more hydrophobicity for microalgae cells attachment. The microalgae cells' adsorption capacity increased by 103%, resulting in a high microalgae growth rate of 3.572 g m-2 d-1. When turning off the light, the surface temperature would cool down to below 20 °C, the surface would shrink. And the biofilm shows a 564.7% increase in desorption ability, realizing temperature-controlled microalgae harvesting.


Assuntos
Microalgas , Dióxido de Carbono , Adsorção , Temperatura , Porosidade , Dióxido de Silício , Fotobiorreatores , Biofilmes , Hidrogéis , Biomassa
4.
Platelets ; 34(1): 2258988, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37722393

RESUMO

This retrospective study aimed to evaluate whether anti-glycoproteins (GPs) autoantibodies can be used as predictors of response to high-dose dexamethasone combined with rituximab (DXM-RTX) in the treatment of primary immune thrombocytopenia (ITP) patients. One-hundred twenty-six ITP patients were included and retrospectively analyzed, 66.7% of anti-GPIb/IX and 65.9% of anti-GPIIb/IIIa autoantibodies. Results showed that overall response (OR) and complete response (CR) rates of patients without anti-GPIb/IX autoantibodies to DXM-RTX were significantly higher than those with anti-GPIb/IX autoantibodies at 4 weeks (OR: 73.8% vs. 47.6%, CR: 50.0% vs. 26.2%; P < 0.05) and 6 months (OR: 71.4% vs. 45.2%, CR: 42.9% vs. 25.0%; P < .05). Furthermore, patients with anti-GPIb/IX single-positivity exhibited higher resistance to DXM-RTX than patients with anti-GPIIb/IIIa single-positivity at 4 weeks (OR: 37.5% vs. 78.3%; P < .05) and 6 months (OR: 29.2% vs. 78.3%; P < .05). Multivariable logistic regression analysis revealed that anti-GPIb/IX autoantibodies and megakaryocytes were associated with the OR rate of patients at both 4 weeks and 6 months, and anti-GPIb/IX autoantibodies at 4 weeks represented the only significant factor affecting OR rate with DXM-RTX (F = 9.128, P = .003). Therefore, platelet anti-GPIb/IX autoantibodies might predict poor response to DXM-RTX in ITP patients.


What is the context?The safety and efficacy of high-dose dexamethasone combined with rituximab (DXM-RTX) in the treatment of primary immune thrombocytopenia (ITP) are gradually recognized; however, there still needs to be an adequate clinical trial to predict its efficacy. Autoantibodies against platelet glycoproteins (GPs) are proven to be associated with a variety of therapeutic responses in ITP. Such as anti-GPIb/IX autoantibodies predict poor response to intravenous immunoglobulin G therapy and rhTPO therapy in ITP patients. Therefore, a retrospective study was needed to verify whether anti-GP autoantibodies can expect a response to DXM-RTX therapy in ITP patients.What is new?This study identified that anti-GPIb/IX autoantibodies were a predictive factor for poor response to DXM-RTX in ITP patients. It mainly manifested in the following aspects: (1) Overall response (OR) and complete response (CR) rates of patients without anti-GPIb/IX autoantibodies to DXM-RTX were significantly higher than those with anti-GPIb/IX autoantibodies at four weeks and six months. (2) Multivariable logistic regression analysis revealed that anti-GPIb/IX autoantibodies at both four weeks and six months were associated with the OR rate of patients.What is the impact?Our study suggests that ITP patients with anti-GPIb/IX positive autoantibodies respond poorly to DXM-RTX therapy. Platelet anti-GPIb/IX autoantibodies might predict poor response to DXM-RTX therapy in ITP patients.


Assuntos
Púrpura Trombocitopênica Idiopática , Humanos , Estudos Retrospectivos , Rituximab/farmacologia , Rituximab/uso terapêutico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Autoanticorpos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas , Dexametasona/farmacologia , Dexametasona/uso terapêutico
5.
J Environ Manage ; 326(Pt A): 116757, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36395642

RESUMO

Biofilm-based microalgae culture combined with wastewater treatment is a promising biotechnology for environmental management. Light availability influences the accumulation of microalgal biomass and nutrient removal. A light attenuation model which comprehensively considered microalgal biofilm structure (density and biofilm thickness), pigments content, and extracellular polymeric substances content was developed to predict the light attenuation in biofilm according to the simplification of the radiative transfer equation. The predicted results were in good overall agreement with the experiment, with an average error of less than 9.02%. These factors (biofilm density, thickness, pigments content, and extracellular polymeric substances content) all contributed to the light intensity attenuation, but biofilm thickness caused the most dramatic attenuation under the same increment of relative change in actual culture. The scattering coefficient of the biofilm (0.433 m2/g) was less than that of the suspension (1.489 m2/g) under white incident light. It suggests that the dense structure of cells allows much light to be concentrated in the forward direction when transmitting. This model could be adopted to predict the light distribution in microalgal biofilm for the further design of efficient photobioreactors and the development of light optimization strategies.


Assuntos
Microalgas , Biofilmes , Fotobiorreatores , Biomassa , Biotecnologia
6.
J Environ Manage ; 325(Pt B): 116582, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36308961

RESUMO

Heterotrophic-assisted photoautotrophic microalgae biofilm cultivation was an alternative way to realize CO2 reduction and wastewater treatment. Growth kinetics supplied a channel to better understand how the cultivation conditions affect microalgal growth and CO2 reduction. However, the two growth modes (heterotroph and photoautotroph) have different needs for organic and inorganic nutrients. Thus, combining the threshold theory and multiplication theory, an integral multifactorial kinetic model that looking insight into the comprehensive effect of glucose, CO2, light intensity, and nitrate was developed for heterotrophic-assisted photoautotrophic microalgae biofilm growth in this study. R2 between model and experiment was 0.99. It predicted the maximum specific growth rate and maximum CO2 consumption rate of heterotrophic-assisted photoautotrophic microalgae biofilm was 1.868 h-1 and 1.02 h-1, respectively. This model fully explained the influence of the main factors on microalgae biofilm growth and reasonably predicted the growth rate of microalgae biofilm under different growth conditions.


Assuntos
Microalgas , Dióxido de Carbono/farmacologia , Glucose/farmacologia , Cinética , Biofilmes , Biomassa
7.
Langmuir ; 38(10): 3284-3296, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35231169

RESUMO

Microalgal biofilm, a stable community of many algal cells attached to a solid substrate, plays a significant role in the efficient accumulation of renewable energy feedstocks, wastewater treatment, and carbon reduction. The adhesion tendency of microalgal cells on solid substrates is the basis for controlling the formation and development of microalgal biofilm. To promote the adhesion of microalgal cells on solid substrates, it is necessary to clarify which surface properties have to be changed in the most critical factors affecting the adhesion. However, there have been few systematic discussions on what surface properties influence the adhesion tendency of algal cells on solid substrates. In this study, the essential principle of microalgal cell adhesion onto solid substrates was explored from the perspective of the interaction energy between microalgal cells and solid substrates. The influence of surface properties between microalgal cells and solid substrates on interaction energies was discussed via extended Derjaguin-Landau-Verwey-Overbeek (eDLVO) theory and a sensitivity analysis. The results showed that surface properties, including surface potential (ξ) and surface free energy components, significantly affect the adhesion tendency of microalgal cells on different solid substrates. When the solid surface possesses positive charges (ξ > 0), reducing ξ or the electron donor components of the solid substrate (γs-) is an effective measure to promote microalgal cell adhesion onto the solid substrate. When the solid surface possesses negative charges (ξ < 0), an increase in either γs- or the absolute value of ξ should be avoided in the process of microalgae adhesion. Overall, this research provides a direction for the selection of solid substrates and a direction for surface modification to facilitate the adhesion tendency of microalgal cells on solid substrates under different scenarios.


Assuntos
Microalgas , Biofilmes , Biomassa , Adesão Celular , Propriedades de Superfície
8.
Environ Res ; 214(Pt 1): 113850, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35817165

RESUMO

Microalgae-based technology provides a potential approach to biologically treating oxytetracycline (OTC) wastewater due to its environmental friendliness, low cost, and high efficiency. However, the OTC degradation and transformation characteristics by microalgae are still unclear and need further exploration. This study used microalgae Chlorella sorokiniana MB-1 for OTC wastewater treatment. The OTC with an initial concentration less than 50 mg L-1 promoted microalgae growth, while OTC with a concentration higher than 100 mg L-1 inhibited microalgae growth significantly. More than 99% OTC was removed with the biomass productivity up to 1.8 g L-1 when treated OTC with 10 mg L-1 initial concentration for 7 days. Chlorophyll and total sugar contents decreased, while protein and lipid contents increased compared to the control without OTC. The malondialdehyde content firstly reduced but subsequently enhanced when increased OTC concentration, while superoxide dismutase content gradually enhanced, manifesting that traces of OTC stimulate microalgae antioxidant capacity, while the increasing OTC caused further oxidative damage to microalgae cells. The removal pathways of OTC mainly include photolysis (75.8%), biodegradation (17.8%), biosorption (3.6%), and hydrolysis (2.7%). Overall, removing OTC by microalgae was confirmed to be an excellent technology for treating antibiotics wastewater whilst accumulating microalgae biomass.


Assuntos
Chlorella , Microalgas , Oxitetraciclina , Purificação da Água , Antibacterianos , Biomassa , Águas Residuárias
9.
Proc Natl Acad Sci U S A ; 116(28): 14349-14357, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31239335

RESUMO

Endocytosis is essential to all eukaryotes, but how cargoes are selected for internalization remains poorly characterized. Extracellular cargoes are thought to be selected by transmembrane receptors that bind intracellular adaptors proteins to initiate endocytosis. Here, we report a mechanism for clathrin-mediated endocytosis (CME) of extracellular lanthanum [La(III)] cargoes, which requires extracellular arabinogalactan proteins (AGPs) that are anchored on the outer face of the plasma membrane. AGPs were colocalized with La(III) on the cell surface and in La(III)-induced endocytic vesicles in Arabidopsis leaf cells. Superresolution imaging showed that La(III) triggered AGP movement across the plasma membrane. AGPs were then colocalized and physically associated with the µ subunit of the intracellular adaptor protein 2 (AP2) complexes. The AGP-AP2 interaction was independent of CME, whereas AGP's internalization required CME and AP2. Moreover, we show that AGP-dependent endocytosis in the presence of La(III) also occurred in human cells. These findings indicate that extracellular AGPs act as conserved CME cargo receptors, thus challenging the current paradigm about endocytosis of extracellular cargoes.


Assuntos
Endocitose/genética , Galactanos/metabolismo , Lantânio/farmacologia , Metais Terras Raras/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Membrana Celular/efeitos dos fármacos , Clatrina/química , Endocitose/efeitos dos fármacos , Galactanos/genética , Humanos , Lantânio/química , Lantânio/metabolismo , Metais Terras Raras/química , Metais Terras Raras/metabolismo , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo
10.
Int J Cancer ; 148(8): 2036-2047, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33403690

RESUMO

Pseudomyxoma peritonei (PMP) is a rare disorder with unique pathological and genetic changes. Although several studies have reported the clinical features and mutational changes of PMP that originates from the appendix, few studies on PMP originating from the ovary have been reported due to its extreme rarity. In order to characterize the somatic mutational landscape and to investigate the prognosis predicting factors of ovary-originating PMP, we examined 830 cases of PMP and identified 16 patients with PMP that originated from the ovary. Whole-exome sequencing (WES) was performed on 12 cases using formalin-fixed, paraffin-embedded (FFPE) tissue samples. We found that 25% (3/12) of the patients carried mutations in cancer driver genes, including TP53, ATM and SETD2, and 16.7% (2/12) of the patients carried mutations in cancer driver genes, including ATRX, EP300, FGFR2, KRAS, NOCR1 and RB1. The MUC16 (58.33%), BSN (41.67%), PCNT (41.67%), PPP2R5A (41.67%), PRSS36 (41.67%), PTPRK (41.67%) and SBF1 (41.67%) genes presented the highest mutational frequencies. The PI3K-Akt signaling pathway, human papillomavirus infection pathway, cell skeleton, cell adhesion, and extracellular matrix and membrane proteins were the major pathways or functions that were affected. Patients were followed up to 174 months (median: 48.26 months). The 5-year OS rate for all patients was 71.2% and the median OS was not reached. PTPRK mutations, presurgical CA199 level, completeness of cytoreduction (CCR) and peritoneal cancer index (PCI) were identified as potential predictive factors for patient survival. In conclusion, the mutational landscape for ovary-originating PMP was revealed and exhibited unique features distinct from appendix-originating PMP. PTPRK, CA199, CCR and PCI may predict patient survival.


Assuntos
Sequenciamento do Exoma/métodos , Predisposição Genética para Doença/genética , Mutação , Ovário/metabolismo , Neoplasias Peritoneais/genética , Pseudomixoma Peritoneal/genética , Adulto , Idoso , Proteínas Mutadas de Ataxia Telangiectasia/genética , Feminino , Histona-Lisina N-Metiltransferase/genética , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Ovário/patologia , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/patologia , Prognóstico , Pseudomixoma Peritoneal/metabolismo , Pseudomixoma Peritoneal/patologia , Proteínas de Ligação a Retinoblastoma/genética , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética
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