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Deep eutectic solvents (DESs), heralded for their synthesis simplicity, economic viability, and reduced volatility and flammability, have found increasing application in biocatalysis. However, challenges persist due to a frequent diminution in enzyme activity and stability. Herein, we developed a general protein engineering strategy, termed corner engineering, to acquire DES-resistant and thermostable enzymes via precise tailoring of the transition region in enzyme structure. Employing Bacillus subtilis lipase A (BSLA) as a model, we delineated the engineering process, yielding five multi-DESs resistant variants with highly improved thermostability, such as K88E/N89â K exhibited up to a 10.0-fold catalytic efficiency (kcat /KM ) increase in 30 % (v/v) choline chloride (ChCl): acetamide and 4.1-fold in 95 % (v/v) ChCl: ethylene glycol accompanying 6.7-fold thermal resistance improvement than wild type at ≈50 °C. The generality of the optimized approach was validated by two extra industrial enzymes, endo-ß-1,4-glucanase PvCel5A (used for biofuel production) and esterase Bs2Est (used for plastics degradation). The molecular investigations revealed that increased water molecules at substrate binding cleft and finetuned helix formation at the corner region are two dominant determinants governing elevated resistance and thermostability. This study, coupling corner engineering with obtained molecular insights, illuminates enzyme-DES interaction patterns and fosters the rational design of more DES-resistant and thermostable enzymes in biocatalysis and biotransformation.
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Disolventes Eutécticos Profundos , Agua , Solventes/química , Lipasa/metabolismo , Biocatálisis , Colina/químicaRESUMEN
An efficient method for the construction of benzo[4,5]imidazo[1,2-a]pyrimidines using N,N-dimethylformamide as a one-carbon source and 2-aminobenzimidazoles and acetophenone as substrates through a one-pot, three-component cascade reaction is described. Spectra investigations indicated the fluorescent properties of selected products, exhibiting quantum yields 0.07-0.16 with maxima absorption at 266-294 nm and emission at 472-546 nm.
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A green and efficient method for the synthesis of oxadiazaborole, dioxazaborinine, and oxadiazaborinine from the reactions of phenylboronic acid with amidoxime, α-hydroxyl oxime and α-hydroxyl hydrazone, respectively, is described. The reactions were performed under catalyst-free and mild conditions. All products can be rapidly purified by filtration and washing. In addition, a set of iminoboronates were prepared following a one-pot multicomponent reaction procedure using α-hydroxyl hydrazone, salicylaldehyde and boronic acid derivatives as starting materials and their photophysical properties were assessed. Then, cross-coupling reactions can be carried out smoothly on some target compounds, which may help develop new boron masking strategies.
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Boro , Hidrazonas , CatálisisRESUMEN
Copper (Cu) and Cu-based nanomaterials have received tremendous attention in recent years because of their unique physicochemical properties and good biocompatibility in the treatment of various diseases, especially cancer. To date, researchers have designed and fabricated a variety of integrated Cu-based nanocomplexes with distinctive nanostructures and applied them in cancer therapy, mainly including chemotherapy, radiotherapy (RT), photothermal therapy (PTT), chemodynamic therapy (CDT), photodynamic therapy (PDT), cuproptosis-mediated therapy, etc. Due to the limited effect of a single treatment method, the development of composite diagnostic nanosystems that integrate chemotherapy, PTT, CDT, PDT, and other treatments is of great significance and offers great potential for the development of the next generation of anticancer nanomedicines. In view of the rapid development of Cu-based nanocomplexes in the field of cancer therapy, this review focuses on the current state of research on Cu-based nanomaterials, followed by a discussion of Cu-based nanocomplexes for combined cancer therapy. Moreover, the current challenges and future prospects of Cu-based nanocomplexes in clinical translation are proposed to provide some insights into the design of integrated Cu-based nanotherapeutic platforms.
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Materiales Biocompatibles , Cobre , Nanocompuestos , Neoplasias , Cobre/química , Cobre/uso terapéutico , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Nanocompuestos/uso terapéutico , Nanocompuestos/química , Materiales Biocompatibles/química , Materiales Biocompatibles/uso terapéutico , Animales , Terapia Fototérmica , Fotoquimioterapia/métodos , Antineoplásicos/uso terapéutico , Antineoplásicos/química , Terapia CombinadaRESUMEN
The heterogeneous monomers obtained from plastic waste degradation are unfavorable for PET recondensation and high-value derivative synthesis. Herein, we developed an efficient chemical-enzymatic approach to convert mixed plastic wastes into homogeneous mono-2-hydroxyethyl terephthalate (MHET) without downstream purification, benefiting from three discovered BHETases (KbEst, KbHyd, and BrevEst) in nature. Towards the mixed plastic waste, integrating the chemical K2CO3-driven glycolysis process with the BHETase depolymerization technique resulted in an MHET yield of up to 98.26 % in 40â h. Remarkably, BrevEst accomplished the highest BHET hydrolysis (~87 % efficiency in 12â h) for yielding analytical-grade MHET compared to seven state-of-the-art PET hydrolases (18 %-40 %). In an investigation combining quantum theoretical computations and experimental validations, we established a MHET-initiated PET repolymerization pathway. This shortcut approach with MHET promises to strengthen the valorization of mixed plastics, offering a substantially more efficient and energy-saving route for PET recycling.
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Reciclaje , Ácidos Ftálicos/química , Plásticos/química , Tereftalatos Polietilenos/química , Hidrólisis , Hidrolasas/metabolismo , PolimerizacionRESUMEN
Deep brain stimulation (DBS) is an effective treatment for neurologic disease and its clinical effect is highly dependent on the DBS leads localization and current stimulating state. However, standard human brain imaging modalities could not provide direct feedback on DBS currents spatial distribution and dynamic changes. Acoustoelectric brain imaging (AEBI) is an emerging neuroimaging method that can directly map current density distribution. Here, we investigate in vivo AEBI of different DBS currents to explore the potential of DBS visualization using AEBI. According to the typical DBS stimulus parameters, four types of DBS currents, including time pattern, waveform, frequency, and amplitude are designed to implement AEBI experiments in living rat brains. Based on acoustoelectric (AE) signals, the AEBI images of each type DBS current are explored and the resolution is quantitatively analyzed for performance evaluation. Furtherly, the AE signals are decoded to characterize DBS currents from multiple perspectives, including time-frequency domain, spatial distribution, and amplitude comparation. The results show that in vivo transcranial AEBI can accurately locate the DBS contact position with a millimeter spatial resolution (< 2 mm) and millisecond temporal resolution (< 10 ms). Besides, the decoded AE signal at DBS contact position is capable of describing the corresponding DBS current characteristics and identifying current pattern changes. This study first validates that AEBI can localize in vivo DBS contact and characterize different DBS currents. AEBI is expected to develop into a noninvasive DBS real-time monitoring technology with high spatiotemporal resolution.
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Estimulación Encefálica Profunda , Animales , Ratas , Humanos , Estimulación Encefálica Profunda/métodos , Encéfalo/fisiología , Cabeza , NeuroimagenRESUMEN
HYPOTHESIS: Chronic wounds, particularly those caused by diabetes, pose a significant challenge for clinical treatment due to their prolonged healing process and associated complications, which can lead to increased morbidity. A biocompatible hydrogel with strong antibacterial properties and the ability to promote angiogenesis can be directly absorbed in the wound site for healing. EXPERIMENTS: A series of self-healing, antibacterial bolaamphiphilic supramolecular self-assembling hydrogels (HLQMes/Cu) were developed based on metal-ligand coordination between various concentrations of Cu2+ solution and the head group of l-histidine methyl ester in HLQMes. This is the first report on the application of bola-molecular supramolecular hydrogels for the treatment of chronic wounds. FINDINGS: The bola-molecular hydrogels reduced the toxicity of copper ions by coordination, and the HLQMes/Cu hydrogel, with 1.3 mg/mL Cu2+ (HLQMes/Cu1.3), demonstrated good biocompatibility and antibacterial properties and effectively enhanced wound healing in a diabetic wound model with full-thickness injuries. Immunohistochemical analysis revealed that the HLQMes/Cu1.3 hydrogel enhanced epithelial formation and collagen deposition in wounds. Immunofluorescence studies confirmed that the HLQMes/Cu1.3 hydrogel attenuated the expression of proinflammatory factor (IL-6) and promoted angiogenesis by upregulating α-SMA and CD31. These findings demonstrate the potential of this bolaamphiphilic supramolecular self-assembling hydrogel as a promising candidate for diabetic wound treatment.
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Diabetes Mellitus , Hidrogeles , Humanos , Hidrogeles/farmacología , Hidrogeles/química , Cobre/farmacología , Cicatrización de Heridas , Antibacterianos/químicaRESUMEN
Metal-organic frameworks (MOFs) have become promising host materials for enzyme immobilization and protection. Herein, ZIF-8 nanocubes were successfully self-assembled onto yeast as a biological template to obtain hybrid Y@ZIF-8. The size, morphology, and loading efficiency of ZIF-8 nanoparticles assembled on yeast templates can be well-regulated by adjusting the various synthetic parameters. Particularly, the amount of water significantly affected the particle size of ZIF-8 assembled on yeast. Through using a cross-linking agent, the relative enzyme activity of Y@ZIF-8@t-CAT could be greatly enhanced and remained the highest even after seven consecutive cycles, with improved cycling stability, as compared to that of Y@ZIF-8@CAT. In addition to the effect of the physicochemical properties of Y@ZIF-8 on the loading efficiency, the temperature tolerance, pH tolerance, and storage stability of Y@ZIF-8@t-CAT were also systematically investigated. Importantly, the catalytic activity of free catalase was decreased to 72% by 45 days, while the activity of the immobilized catalase remained above 99%, suggesting good storage stability. The present work demonstrates that yeast-templated ZIF-8 nanoparticles have a high potential to be used as biocompatible immobilization materials and are promising candidates for the preparation of effective biocatalysts in biomedicine applications.
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Enzimas Inmovilizadas , Estructuras Metalorgánicas , Enzimas Inmovilizadas/química , Estructuras Metalorgánicas/química , Catalasa , Saccharomyces cerevisiae/metabolismo , BiocatálisisRESUMEN
Objective: Acoustoelectric brain imaging (AEBI) is a promising imaging method for mapping brain biological current densities with high spatiotemporal resolution. Currently, it is still challenging to achieve human AEBI with an unclear acoustoelectric (AE) signal response of medium characteristics, particularly in conductivity and acoustic distribution. This study introduces different conductivities and acoustic distributions into the AEBI experiment, and clarifies the response interaction between medium characteristics and AEBI performance to address these key challenges. Approach: AEBI with different conductivities is explored by the imaging experiment, potential measurement, and simulation on a pig's fat, muscle, and brain tissue. AEBI with different acoustic distributions is evaluated on the imaging experiment and acoustic field measurement through a deep and surface transmitting model built on a human skullcap and pig brain tissue. Main results: The results show that conductivity is not only inversely proportional to the AE signal amplitude but also leads to a higher AEBI spatial resolution as it increases. In addition, the current source and sulcus can be located simultaneously with a strong AE signal intensity. The transcranial focal zone enlargement, pressure attenuation in the deep-transmitting model, and ultrasound echo enhancement in the surface-transmitting model cause a reduced spatial resolution, FFT-SNR, and timing correlation of AEBI. Under the comprehensive effect of conductivity and acoustics, AEBI with skull finally shows reduced imaging performance for both models compared with no-skull AEBI. On the contrary, the AE signal amplitude decreases in the deep-transmitting model and increases in the surface-transmitting model. Significance: This study reveals the response interaction between medium characteristics and AEBI performance, and makes an essential step toward developing AEBI as a practical neuroimaging technique.
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OBJECTIVES: The present study is designed to investigate the role of vagus nerve in the treatments of irritable bowel syndrome (IBS) and the associated central nervous system disorders. METHODS: An IBS animal model was established by giving acetic acid and chronic-acute stress (AA-CAS) treatment in adult male Wistar rats. Subdiaphragmatic vagotomy (SDV) and vagus nerve stimulation (VNS) were performed to intervene the excitability of vagus nerve. Permeability of blood brain barrier (BBB) was measured and agonist and antagonist of α7 nicotinic acetylcholine receptor (α7nAChR) were used to explore the relevant mechanisms. RESULTS: AA-CAS treatment resulted in abnormal fecal output, increased visceral sensitivity, depressive-like behaviors, and overexpression of inflammatory mediators, all of which were reversed by VNS treatment. The effects of VNS could also be observed when α7nAChR agonist was applied. Whereas α7nAChR antagonist (methyllycaconitine, MLA) reversed VNS's effects. Interestingly, VNS also reduced the increased permeability of blood brain barrier (BBB) following AA-CAS treatment in IBS rats. SDV treatment only show temporary efficacy on AA-CAS-induced symptoms and had no effect on the permeability of BBB. CONCLUSION: The intestinal abnormalities and depressive symptoms in IBS rats can be improved by VNS treatment. This positive effect of VNS was achieved through α7nAChR-mediated inflammatory pathway and may also be associated with the decreased of BBB permeability.
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Although considerable research achievements have been made to address the plastic crisis using enzymes, their applications are limited due to incomplete degradation and low efficiency. Herein, we report the identification and subsequent engineering of BHETases, which have the potential to improve the efficiency of PET recycling and upcycling. Two BHETases (ChryBHETase and BsEst) are identified from the environment via enzyme mining. Subsequently, mechanism-guided barrier engineering is employed to yield two robust and thermostable ΔBHETases with up to 3.5-fold enhanced kcat/KM than wild-type, followed by atomic resolution understanding. Coupling ΔBHETase into a two-enzyme system overcomes the challenge of heterogeneous product formation and results in up to 7.0-fold improved TPA production than seven state-of-the-art PET hydrolases, under the conditions used here. Finally, we employ a ΔBHETase-joined tandem chemical-enzymatic approach to valorize 21 commercial post-consumed plastics into virgin PET and an example chemical (p-phthaloyl chloride) for achieving the closed-loop PET recycling and open-loop PET upcycling.
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Hidrolasas , Tereftalatos Polietilenos , Hidrolasas/genética , Hidrolasas/metabolismo , Plásticos/metabolismo , Tereftalatos Polietilenos/metabolismo , ReciclajeRESUMEN
Idiopathic interstitial pneumonia (IIP) is a group of progressive lower respiratory tract diseases of unknown origin characterized by diffuse alveolitis and alveolar structural disorders leading to pulmonary fibrillation and hypertension, pulmonary heart disease, and right heart failure due to pulmonary fibrosis, and more than half of them die from respiratory failure. To address these problems of overly complex prediction methods and large data sets involved in the prediction process of interstitial pneumonia, this paper proposes a prediction model for interstitial pneumonia which is based on the Gaussian Parsimonious Bayes algorithm. Three usual tests of pneumonia, specifically from various patients, were collected as the sample set. These samples are divided into training and testing sets. Additionally, a cross-validation strategy was used to avoid the overfitting problem. The results showed that the prediction model based on the Gaussian Parsimonious Bayes algorithm predicted 92% accuracy on the test set, and the Parsimonious Bayes method could directly predict the final detection of interstitial pneumonia based on the usual pneumonia test pneumonia. In addition, it was found that the closer the data distribution of the sample set was to a normal distribution, the higher the prediction accuracy was, and then, after excluding pneumonia from the test below 60 points, the prediction accuracy reached 96%.
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Neumonías Intersticiales Idiopáticas , Enfermedades Pulmonares Intersticiales , Algoritmos , Teorema de Bayes , Humanos , Neumonías Intersticiales Idiopáticas/diagnóstico , Neumonías Intersticiales Idiopáticas/patología , Pulmón , Enfermedades Pulmonares Intersticiales/diagnóstico , Enfermedades Pulmonares Intersticiales/patologíaRESUMEN
Introduction: To probe the impacts and biological roles of miR-4739/ITGA10 on the proliferation, differentiation and apoptosis of osteoblasts. Methods: Bioinformatics analysis was conducted to screen the key genes in osteoporosis. The upstream miRNAs of ITGA10 were predicted by TargetScan. KEGG pathway enrichment analysis was performed by DAVID database. The osteoblast proliferation and apoptosis were measured using CCK-8 and flow cytometry. The differentiation markers were measured by qRT-PCR and western blotting. The luciferase reporter assay was conducted to verify the binding of miR-4739 to ITGA10. Results: ITGA10 was down-regulated in patients with osteoporosis and identified as the key gene in osteoporosis by the bioinformatics analysis. Then the prediction provided by TargetScan indicated that miR-4739 was the potential upstream miRNA for ITGA10. And the following luciferase reporter assay showed that miR-4739 could bind to ITGA10 3'UTR. Furthermore, the miR-4739 inhibitor promoted osteoblasts proliferation, differentiation, and inhibited cell apoptosis by increasing the expression of ITGA10 and subsequently activating the PI3K/AKT signaling pathway. Conclusions: Overall, we proved that the higher expression of miR-4739 participated in the progression of osteoporosis by targeting ITGA10 and modulating PI3K/AKT signaling pathway, and perhaps miR-4739/ITGA10 axis could be potential diagnostic markers and therapeutic target for osteoporosis.
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Two-dimensional (2D) metal-organic frameworks (MOFs) could serve as multifunctional nanoplatforms to load small-molecule drugs and enzyme-mimicking nanoparticles (NPs) with a high efficiency for combined cancer therapy. Herein, we have prepared novel 2D Cu-tetrakis (4-carboxyphenyl) porphyrin (TCPP) nanosheets with an average thickness of 1.2 ± 0.1 nm using Cu2O nanocubes (50 nm) as a template and solid copper ion supplier. Cu2O nanocubes can be consumed and hybridized with the obtained Cu-TCPP, depending on the molar ratio of Cu2O and TCPP linker. The resultant Cu2O/Cu-TCPP could serve as nanoplatforms for co-loading of Pt and Au NPs to construct multifunctional Cu2O/Cu-TCPP/(Pt-Au) nanomedicines, which showed a superior anticancer effect via multiple therapeutic modes. For instance, Cu(II)-TCPP can produce 1O2 in the presence of acidic H2O2 by the Russell mechanism and the intrinsic Cu(I) ions (derived from the residual Cu2O) could mediate a Fenton-like reaction in tumorous tissues to generate toxic hydroxyl radicals (â¢OH). Moreover, the loaded Pt NPs with catalase (CAT)-mimic activity could decompose hydrogen peroxide (H2O2) into O2 within the tumor cells, increasing the local O2 concentration, modulating the tumorous hypoxia atmosphere, and promoting the O2-dependent glucose oxidation reaction. Furthermore, Au NPs with glucose oxidase (GOx)-mimic activity could accelerate the consumption of glucose and cut nutrient supply to induce starvation therapy. Consequently, our designed 2D MOF-based therapeutic nanomedicines would be a promising candidate for future smart and combined cancer therapy.
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Neoplasias , Porfirinas , Glucosa/uso terapéutico , Humanos , Peróxido de Hidrógeno/uso terapéutico , Neoplasias/tratamiento farmacológico , Porfirinas/farmacología , Porfirinas/uso terapéuticoRESUMEN
Heterogenization of biomolecules by immobilizing on a metal oxide support could greatly enhance their catalytic activity and stability, but their interactions are generally weak. Herein, cobalt phthalocyanine (CoPc) molecules were firmly anchored on a Ce-based metal-organic framework (Ce-BTC) due to π-π stacking interaction between CoPc and aromatic frameworks of the BTC linker, which was followed by a calcination treatment to convert Ce-BTC to mesoporous CeO2 and realize a molecular-level dispersion of CoPc on the surface of CeO2. Various characterization results confirm the successful fabrication of molecular-based CoPc/CeO2 catalysts which exhibited good CO oxidation performance. Importantly, we found that the mixing manner of Ce-BTC and CoPc remarkably affects the physicochemical properties which then determined the catalytic performance of the resultant CoPc/CeO2 catalysts. In contrast, the direct physical mixing of CoPc and CeO2 led to poor performance toward CO oxidation, manifesting that the Ce-BTC-mediated CoPc loading strategy is promising for the heterogenization of catalytic biomolecules.
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Amphiphobic surfaces have been developed for various applications. However, the harsh construction conditions and multistep processes limit their practical application. Especially for those with a particular surface roughness and morphology, the amphiphobic property might provide a slight deformation. Here, a facile large-area construction of transparent and flexible amphiphobic coatings with excellent fold resistance has been established by simple casting of the fluorinated liquid nitrile-butadiene rubber (F-LNBR) followed by solvent-free photocuring. It was found that the fluorocarbon groups could concentrate onto the coating surface during the UV-induced photocuring. With a certain coating amount, a stable oleophobic coating was achieved with static contact angles of about 95° and 111° for nonpolar oil (n-hexadecane) and polar oil (diiodomethane). Most importantly, the static contact angles of water and diiodomethane of the amphiphobic coatings on the iron sheet increased after bending and remained around 131° and 120° after being completely folded in half for 100 cycles because the inner fluorocarbon groups could be squeezed out from the flexible cross-linked rubber matrix as a reservoir. Such features indicated the promising self-cleaning and surface protection of the proposed transparent and flexible amphiphobic coatings for deformable substrates.
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It has been certified that GABPB1-AS1 is aberrantly expressed and plays as a vital role in some kinds of cancers. However, its expression pattern and functions in non-small cell lung cancer (NSCLC) are still largely unknown. This study aims to assess GABPB1-AS1 expression and biological roles in NSCLC. The expression of GABPB1-AS1 was detected in NSCLC specimens and adjacent normal specimens. CCK8 and Transwell assays were performed to evaluate the effects of GABPB1-AS1 on NSCLC cell proliferation, migration and invasion. Bioinformatics tools and luciferase reporter assays were applied to predict and verify GABPB1-AS1's direct targets. The results revealed that GABPB1-AS1 is sharply reduced in NSCLC specimens and cell lines. CCK8 assays indicated that overexpression of GABPB1-AS1 dramatically reduced NSCLC cell growth, and Transwell assays proved that NSCLC cell migration and invasion were distinctly inhibited by GABPB1-AS1. Exploration of the mechanism uncovered that miRNA-566 (miR-566)/F-box protein 47 (FBXO47) is directly targeted by GABPB1-AS1 in NSCLC. The study demonstrated that GABPB1-AS1 inhibited NSCLC cell proliferation, migration and invasion by targeting miR-566/FBXO47.
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Carcinoma de Pulmón de Células no Pequeñas , Proteínas F-Box , Neoplasias Pulmonares , MicroARNs , Humanos , MicroARNs/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , Línea Celular , Factor de Transcripción de la Proteína de Unión a GA , Factores de TranscripciónRESUMEN
Metal-organic frameworks (MOFs) have received extensive attention in the field of biomedicine, particularly serving as multifunctional theranostic nanoplatforms by integrating chemodrugs, imaging agents, and targeting agents. Herein, we report a facile strategy for the fabrication of a hollow and monodisperse MOF (denoted hMIL-88B(Fe)@ZIF-8) consisting of ZIF-8 nanoparticles loaded on the external shell of hollow MIL-88B(Fe). In particular, the hybrid hollow MOF was constructed by partially etching spindlelike MIL-88B(Fe) nanoparticles with 2-methylimidazole in the presence of zinc ions. The obtained hMIL-88B(Fe)@ZIF-8 was then used as a drug/cargo delivery vehicle for loading doxorubicin (DOX), manganese oxide (MnOx) nanoparticles, and folic acid (FA), forming a multifunctional nanoplatform (denoted hM@ZMDF). Importantly, the resulting hM@ZMDF exhibited a specific targeting property for the FA receptor-overexpressed cancer cells (MCF-7 and HepG-2 cells) and then it unloaded DOX and Fe3+ in the tumor microenvironment. Consequently, DOX played dual roles as a chemotherapeutic drug and a fluorescent imaging agent. Also, the released Fe3+ could mediate the Fenton reaction and intracellularly generate toxic hydroxyl radicals in the presence of high glutathione in cancer cells. In addition, MnOx nanoparticles could participate in magnetic resonance imaging. Therefore, the versatile hM@ZMDF nanoplatforms have great potential for smart cancer therapy.
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Estructuras Metalorgánicas , Nanopartículas , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos , Ácido Fólico , Nanopartículas/uso terapéuticoRESUMEN
To decrease d-lactic acid production cost, sugarcane molasses and soybean meal, low-cost agro-industrial wastes, were selected as feedstock. First, sugarcane molasses was used directly by Lactobacillus delbrueckii S-NL31, and the nutrients were released from soybean meal by protease hydrolysis. Subsequently, to ensure intensive substrate utilization and enhanced d-lactic acid production from sugarcane molasses and soybean meal, adaptation of L. delbrueckii S-NL31 to substrates was performed through adaptive laboratory evolution. After two-phase adaptive laboratory evolution, the evolved strain L. delbrueckii S-NL31-CM3-SBM with improved cell growth and d-lactic acid production on sugarcane molasses and soybean meal was obtained. To decipher the potential reasons for improved fermentation performance, a metabolomics-based approach was developed to profile the differences of intracellular metabolism between initial and evolved strain. The in-depth analysis elucidated how the key factors exerted influence on d-lactic acid biosynthesis. The results revealed that the enhancement of glycolysis pathway and cofactor supply was directly associated with increased lactic acid production, and the reinforcement of pentose phosphate pathway, amino acid metabolism, and oleic acid uptake improved cell survival and growth. These might be the main reasons for significantly improved d-lactic acid production by adaptive laboratory evolution. Finally, fed-batch simultaneous enzymatic hydrolysis of soybean meal and fermentation process by evolved strain resulted in d-lactic acid levels of 112.3 g/L, with an average production efficiency of 2.4 g/(L × h), a yield of 0.98 g/g sugar, and optical purity of 99.6%. The results show the applicability of d-lactic acid production in L. delbrueckii fed on agro-industrial wastes through adaptive laboratory evolution.
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Glycine max/microbiología , Ácido Láctico/biosíntesis , Lactobacillus delbrueckii/metabolismo , Saccharum/microbiología , Fermentación , Residuos Industriales/análisis , Lactobacillus delbrueckii/genética , Lactobacillus delbrueckii/crecimiento & desarrollo , Metabolómica , Melaza/análisis , Melaza/microbiología , Saccharum/metabolismo , Glycine max/metabolismo , Residuos/análisisRESUMEN
OBJECTIVE: To evaluate the effect on increasing bone cement-bone interface micro-gomphosis intensity with bone cement oscillator. METHODS: One hundred femoral bones of adult pig were randomly divided into 6 groups: oscillating group (A1) and control group (A2) of anti-tensile force, oscillating group (B1) and control group (B2) of anti-pressure (n = 20 in each group), oscillating group (C1) and control group (C2) of imaging (n = 10 in each group). Mechanics and CT test was performed, micro-gomphosis intensity of bone cement-bone interface between oscillating group and control group was compared. RESULTS: Mechanics and CT test showed bone cement-bone interface micro-gomphosis intensity in oscillating group was significantly stronger than control group (P < 0.01). CONCLUSION: Bone cement oscillator can significantly increase micro-gomphosis intensity of bone-cement interface, and reduce long-term aseptic loosening of artificial prostheses.