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1.
Chemosphere ; 286(Pt 2): 131702, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34343916

RESUMEN

The ozonation process of Bisphenol A (BPA) in a rotating packed bed (RPB) was modeled by response surface methodology (RSM) and artificial neural network (ANN). Experiments were performed according to the Box-Behnken design, and the interactive effects of various parameters including ozone concentration, pH, rotation speed of RPB and liquid flow rate on BPA degradation efficiency were investigated. Ozone concentration and pH had the most significant interactive effects on BPA degradation efficiency while rotation speed of RPB had no significant interactive effects with other variables. A second order polynomial equation was obtained to predict BPA degradation efficiency. Also, a multi-layered feed-forward ANN model was constructed based on the data of RSM experiments. Six neurons in hidden layer had the highest correlation coefficient (RANN = 0.99158). A comparison between RSM and ANN models suggested that both can accurately predict BPA degradation efficiency (RRSM = 0.99559). The highest BPA degradation efficiency (99.52 %) was achieved under the conditions of ozone concentration of 20 mg L-1, pH of 11, liquid flow rate of 10 L h-1 and rotation speed of RPB of 800 rpm, which was well predicted by the RSM model (99.54 %) and the ANN model (99.82 %). However, the RSM model was slightly better than the ANN model owing to its higher determination coefficient (R2RSM = 0.9912, R2ANN = 0.9827) and lower mean square error (MSERSM = 0.0001684, MSEANN = 0.0003305).


Asunto(s)
Compuestos de Bencidrilo , Ozono , Redes Neurales de la Computación , Fenoles
2.
J Virol Methods ; 299: 114345, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34728272

RESUMEN

The hepatoma cell lines stably expressing sodium taurocholate cotransporting polypeptide (NTCP), the receptor of hepatitis B virus (HBV) infection, serve as important infection models for studying viral biology and drug discovery. However, the efficiency of infection greatly varies. In this study, we studied the effects and potential mechanisms of Matrigel® hESC-qualified (M-hq), a biological basement membrane matrix commonly used in cell culture, on promotion HBV in vitro infection in HepG2-NTCP cells. For the first time, our findings demonstrate that M-hq could enhance the infection efficiency of cell culture-derived HBV with no impact on the cell viability, the HBV transcription and response to antiviral treatments. The infection enhancement is reproducible and is suggested to occur at HBV attachment step. Our study suggests that this novel system is applicable for studying HBV biology and new drugs.

3.
Sci Total Environ ; 806(Pt 4): 150779, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34619208

RESUMEN

Plastic products made of polyethylene (PE), polypropylene (PP), and polystyrene (PS) are widely used in daily life and industrial production. Polyolefins-which have a very stable structure and do not contain any active molecular groups-are difficult to degrade and pose a serious global environment threat. This study selected latex clearing protein (LcpK30) derived from Streptomyces sp. Strain K30. The natural substrate of the enzyme is rubber (cis-1, 4-polyisoprene), and the site of action is the carbon­carbon double bond. LcpK30 was incubated with UV-irradiated polyolefin PE, PP and PS (UV-PE, UV-PP, and UV-PS containing carbon­carbon double bonds) for 5 d at 37 °C. The results showed that UV-PE-LcpK30 was more fragmented than UV-PE-blank; the Fourier transform infrared spectroscopy results showed that UV-PE-LcpK30 and UV-PP-LcpK30 produced new active groups (e.g., -OH and -C=O); however, the effect on UV-PS was not significant. Scanning electron microscopy results showed that the treated group had more obvious roughness, cracks, and pits than the control group. The results of high-temperature gel permeation chromatography showed that the average molecular weight (Mw) of UV-PE-LcpK30 and UV-PP-LcpK30 decreased; the Mw of UV-PE5-LcpK30 was reduced by 42.02%. The results of gas chromatography-mass spectrometry showed the production of ketones. Therefore, the LcpK30 latex clearing protein degrade UV-oxidized polyolefin plastics and has great potential for PE and PP degradation but may not be suitable for PS. Furthermore, other Lcps (such as LcpNRRL, LcpNVL3) can also degrade UV-PE.

4.
Sci Total Environ ; 805: 150210, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34534871

RESUMEN

As more and more countries have prohibited the manufacture and sale of plastic products with bisphenol A (BPA), a number of bisphenol analogues (BPs), including BPS, BPF and BPAF, have gradually been used as its primary substitutes. Ideally, substitutes used to replace chemicals with environmental risks should be inert, so it makes sense that the risk of the similar chemical substitutes (BPS, BPF, and BPAF) should be assessed before they used. Therefore, in the present study, the neurotoxicity of four BPs at environmentally relevant concentration (200 µg/L) were systematically compared using zebrafish as a model. Our results showed that the four BPs (BPA, BPS, BPF and BPAF) exhibited no obvious effect on the hatchability, survival rate and body length of zebrafish larvae, noteworthily a significant inhibitory effect on spontaneous movement at 24 hpf was observed in the BPA, BPF and BPAF treatment groups. Behavioral tests showed that BPAF, BPF and BPA exposure significantly reduced the locomotor activity of the larvae. Additionally, BPAF treatment adversely affected motor neuron axon length in transgenic lines hb9-GFP zebrafish and decreased central nervous system (CNS) neurogenesis in transgenic lines HuC-GFP zebrafish. Intriguingly, BPAF displayed the strongest effects on the levels and metabolism of neurotransmitters, followed by BPF and BPA, while BPS showed the weakest effects on neurotransmitters. In conclusion, our study deciphered that environmentally relevant concentrations of BPs exposure exhibited differential degrees of neurotoxicity, which ranked as below: BPAF > BPF ≈ BPA > BPS. The possible mechanisms can be partially ascribed to the dramatical changes of multiple neurotransmitters and the inhibitory effects on neuronal development. These results suggest that BPAF and BPF should be carefully considered as alternatives to BPA.


Asunto(s)
Compuestos de Bencidrilo , Pez Cebra , Animales , Compuestos de Bencidrilo/toxicidad , Larva , Fenoles/toxicidad
5.
Food Chem ; 372: 131118, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34600194

RESUMEN

To systematically study the impact of root restriction (RR) on the aroma quality of grape berry, in this study, free and bound compounds were investigated in 'Red Alexandria' grape skin and pulp produced with and without RR during development and ripening. Compared with the control, RR advanced the initiation of free-terpene synthesis and increased their concentrations at 14-18 weeks post-flowering (wpf) by promoting the conversion of bound terpenes to free terpenes. In addition, RR significantly regulated the aromatic series at 14-18 wpf and advanced the date of aroma maturation. Network analyses indicated that the correlations among bound compounds were more conserved than those among free compounds, and the skin network displayed tight coordination compared with the pulp network. Terpenes were highly intercorrelated and played a core role in these networks. Finally, 10 bound compounds in pulp were screened out as indicators of the developmental timing of grape.


Asunto(s)
Vitis , Frutas , Odorantes , Terpenos
6.
Magn Reson Med ; 87(1): 431-445, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34337773

RESUMEN

PURPOSE: MRI of organs and musculoskeletal structures in the female pelvis presents a unique display of pelvic anatomy. Automated segmentation of pelvic structures plays an important role in personalized diagnosis and treatment on pelvic structures disease. Pelvic organ systems are very complicated, and it is a challenging task for 3D segmentation of massive pelvic structures on MRI. METHODS: A new Scale- and Slice-aware Net ( S 2 aNet) is presented for 3D dense segmentation of 54 organs and musculoskeletal structures in female pelvic MR images. A Scale-aware module is designed to capture the spatial and semantic information of different-scale structures. A Slice-aware module is introduced to model similar spatial relationships of consecutive slices in 3D data. Moreover, S 2 aNet leverages a weight-adaptive loss optimization strategy to reinforce the supervision with more discriminative capability on hard samples and categories. RESULTS: Experiments have been performed on a pelvic MRI cohort of 27 MR images from 27 patient cases. Across the cohort and 54 categories of organs and musculoskeletal structures manually delineated, S 2 aNet was shown to outperform the UNet framework and other state-of-the-art fully convolutional networks in terms of sensitivity, Dice similarity coefficient and relative volume difference. CONCLUSION: The experimental results on the pelvic 3D MR dataset show that the proposed S 2 aNet achieves excellent segmentation results compared to other state-of-the-art models. To our knowledge, S 2 aNet is the first model to achieve 3D dense segmentation for 54 musculoskeletal structures on pelvic MRI, which will be leveraged to the clinical application under the support of more cases in the future.

7.
Dev Comp Immunol ; 127: 104292, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34656643

RESUMEN

Vibrio harveyi is a zoonotic pathogen that can infect humans through wounds and cause severe inflammatory responses. Previous studies have reported that the Toll like receptors (TLR) mediated MAPK, AKT and NF-κB signaling pathways are involved in innate immune system resistance to pathogen invasion. However, the molecular mechanism of these pathways, as well as their involvement in V. harveyi infection remains elusive. This study established a V. harveyi infection model using murine peritoneal macrophages (PMs). Various techniques, including western blotting, ELISA, RT-qPCR, immunofluorescence, inhibition assays, were used to explore the roles of TLRs, MAPK, AKT and NF-κB signaling pathways in V. harveyi-induced inflammatory responses. ELISA assays showed that V. harveyi infection triggered proinflammatory cytokines secretion in PMs. RT-qPCR and inhibition assays showed that TLR2 participated in V. harveyi infection and up-regulated the proinflammatory cytokines secretion in murine PMs. Western blotting data showed that the phosphorylation of p38, JNK, AKT, and NF-κB p65 were significantly increased partly mediated by TLR2. In addition, immunofluorescence assays revealed that the NF-κB p65 translocated into nucleus in response to V. harveyi infection. The secretion of IL-1ß, IL-6, IL-12, and TNF-α were considerably reduced when the p38 MAPK and NF-κB signaling pathways were blocked, whereas blocking of AKT significantly increased the expression of IL-1ß, IL-6, IL-12, and TNF-α. These findings indicate that V. harveyi infection induces inflammatory responses in murine PMs via activation of p38 MAPK and NF-κB pathways, which are partly mediated by TLR2, but are inhibited by PI3K/AKT pathways.

8.
J Clin Anesth ; 76: 110575, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34739947

RESUMEN

STUDY OBJECTIVES: Enhanced recovery after surgery (ERAS) protocols have been proven to improve outcomes but have not been widely used in neurosurgery. The purpose of this study was to design a multidisciplinary enhanced recovery after elective craniotomy protocol and to evaluate its clinical efficacy and safety after implementation. DESIGN: A prospective randomized controlled trial. SETTING: The setting is at an operating room, a post-anesthesia care unit, and a hospital ward. PATIENTS: This randomized controlled trial (RCT) prospectively analyzed 151 patients who underwent elective craniotomy between January 2019 and June 2020. INTERVENTIONS: The neurosurgical ERAS group was cared for with evidence-based systematic optimization approaches, while the control group received routine care. MEASUREMENTS: The primary outcomes were the postoperative length of stay (LOS) and hospitalization costs. The secondary outcomes included 30-day readmission rates, postoperative complications, postoperative pain scores, length of intensive care unit (ICU) stay, duration of the drainage tube, time to oral intake, time to ambulation, and postoperative functional recovery status. MAIN RESULTS: After ERAS protocol implementation, the median postoperative LOS (4 days to 3 days, difference [95% confidence interval, CI], 2 [1 to 2], P < 0.0001) and hospitalization costs (6266 USD to 5880 USD, difference [95% CI], 427.0 [234.8 to 633.6], P < 0.0001) decreased. Compared to routine perioperative care, the ERAS protocol reduced the incidence of postoperative nausea and vomiting (PONV) (28.0% to 9.2%, adjusted odds ratio [OR] 0.3, 95% CI 0.1-0.7, P = 0.003), shortened urinary catheter removal time by 24 h (64.0% to 83.0%, adjusted OR 2.9, 95% CI 1.3-6.5, P = 0.031), improved ambulation on postoperative day 1 (POD 1) (30.7% to 75.0%, adjusted OR 7.5, 95% CI 3.6-15.8, P < 0.0001), shortened the time to oral intake (15 h to 13 h, difference [95% CI], 3 [1 to 4], P < 0.001), and improved perioperative pain management. CONCLUSIONS: Implementation of an enhanced recovery after elective craniotomy protocol had significant benefits over conventional perioperative management. It was associated with a significant reduction in postoperative length of stay, medical cost, and postoperative complications.

9.
J Ethnopharmacol ; 283: 114705, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34655669

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Dan-Deng-Tong-Nao Capsules (DDTNC) is a Chinese patent medicine and has been used in treating cerebral ischemic stroke (IS) for a long time in China, protection of brain microvascular endothelial cells (BMECs) is the main treatment strategy. But the holistic chemical information and potential bioactive components of DDTNC on protecting BMECs and its underlying mechanism is still unclear. AIM OF THE STUDY: To identify the active ingredients of DDTNC and to explore the protective effects of DDTNC on BMECs associated with Wnt/ß-catenin pathway. MATERIALS AND METHODS: The components of DDTNC and cerebrospinal fluid containing composition of DDTNC (DDTNC-CSF) were detected by High performance liquid chromatography combined with Diode array detector (HPLC-DAD) and Ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), respectively. The experiment rat model was established with middle cerebral artery occlusion (MCAO), the therapeutic effects of DDTNC were assessed by Longa assay and TTC staining. The cerebral micro vessel density was determined by immunofluorescence staining. The injured BMECs caused by oxygen-glucose deprivation and reperfusion (OGD/R) was used to evaluate the protective effect of cerebrospinal fluid containing composition of DDTNC (DDTNC-CSF). The cell survival rate was detected by the method of CCK-8, the intracellular Ca2+ and reactive oxygen species (ROS) was estimated by Fluo-3. Moreover, the proteins of Bax, Bcl-2, Wnt, ß-catenin, GSK-3ß was determined by Western blotting. RESULTS: The RSD values of all methodological studies were less than 3.0%. A total of 20 compounds were detected under the optimized HPLC-DAD chromatographic condition. In the UPLC-Q-TOF-MS negative mode, peak 1 and peak 2 were detecteted in DDTNC-CSF and was identified as Danshensu and Puerarin, respectively. In the UPLC-Q-TOF-MS positive mode, peak 1 and peak 3 were detecteted in DDTNC-CSF and was identified as Danshensu and Scutellarin, respectively. DDTNC significantly decreased the Longa values and infarct volume and significantly increased the cerebral microvessel density of the MCAO rats. The accumulation of intracellular Ca2+ and ROS in BMECs injured by OGD/R decreased significantly in DDTNC-CSF group. The expression of Bcl-2, ß-catenin, wnt-1 was upregulated by DDTNC-CSF and the level of Bax and GSK3ß could be downregulated by DDTNC-CSF. CONCLUSION: The present study provided a scientific basis for revealing the mechanism of DDTNC in the treatment of IS and DDTNC is expected to be an effective drug for the treatment of IS.

10.
J Hazard Mater ; 423(Pt A): 127043, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34479084

RESUMEN

Bioremediation by phosphate-solubilizing bacteria (PSB) has attracted extensive attentions due to its economical and eco-friendly properties for lead (Pb) passivation in soil. Herein, bone char (BC) supported biochemical composite (CFB1-P) carrying advantages of BC, PSB, iron sulfide (FeS) and carboxymethyl cellulose (CMC) was designed and applied to Pb passivation. The composite at a mass ratio of BC:CMC:FeS = 1:1:1 possessed high passivation efficiency (65.47%), and has been demonstrated to offer appropriate habitat environment for PSB to defend against Pb(II) toxicity, thus enhancing the phosphate-solubilizing amount of PSB to 140.72 mg/L for passivating Pb(II). Batch experiments showed that the CFB1-P possessed excellent adsorption properties with maximal monolayer Pb(II) uptake of 452.99 mg/g during an extensive pH range of 2.0-6.0. Furthermore, by applying CFB1-P dosage of 3% into Pb-contaminated soil, the labile Pb fractions were reduced from 29.05% to 6.47% after simulated remediation of 10 days, and converted into steady fractions. The CFB1-P was demonstrated to achieve high Pb(II) passivation through combined functions of chemical precipitation, complexation, electrostatic attraction and biomineralization, accompanied by the formation of more stable crystal structures, for instance, Pb5(PO4)3OH, Pb3(PO4)2 and PbS. These results suggested CFB1-P as a potential alternative for efficient remediation of Pb-contaminated soil.

11.
J Hazard Mater ; 423(Pt A): 127025, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34481391

RESUMEN

Municipal solid waste incineration (MSWI) fly ash is a typical hazardous waste worldwide. In this study, an innovative magnesium oxysulfate cement (MOSC) binder was designed for stabilization/solidification (S/S) of MSWI fly ash, focusing on the interactions between MOSC binder and typical metallic cations (Pb2+)/oxyanions (AsO33-). Experimental results showed that Pb and As slightly inhibited the reaction of high-sulfate 5MS system but significantly suppressed the reaction process of low-sulfate 10MS system. The 5MS binder system exhibited excellent immobilization efficiencies (99.8%) for both Pb and As. The extended X-ray absorption fine structure spectra suggested that Pb2+ coordinated with SO42-/OH- in the MOSC system and substituted Mg2+ ion sites in the internal structure of 5Mg(OH)2·MgSO4.7H2O (5-1-7) phase. In contrast, the AsO33- substituted SO42- sites with the formation of inner-sphere complexes with Mg2+ in the large interlayer space of the 5-1-7 structure. Subsequent MSWI fly ash S/S experiments showed that a small amount of reactive Si in MSWI fly ash interfered with the MOSC reaction and adversely influenced the immobilization efficiencies of Pb, As, and other elements. Through the use of 33 wt% tailored MOSC binder for MSWI fly ash treatment, a satisfying S/S performance could be achieved.

12.
J Hazard Mater ; 423(Pt A): 127079, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34488102

RESUMEN

Sorption/desorption of two organic compounds (OCs), phenanthrene (PHE), and 1-nitronaphthalene (1-Nnap) on three polar and one nonpolar polypropylene (PP) microplastics (MPs) and earthworm bioaccumulation of MP associated PHE were systematically studied. Poly-butylene succinate (PBS) with the lowest glass transition temperature (Tg) showed the highest sorption toward PHE and 1-Nnap (Kd: 25,639 ± 276 and 1673 ± 28.8 L kg-1, respectively), while polylactic acid (PLA) with the highest Tg showed the least sorption (182 ± 5 and near 0), confirming that hydrophobic partition was the main driving force of sorption. However, polar interactions also contributed to the preferential sorption of 1-Nnap on polar poly-hydroxyalkanoates (PHA). Moreover, small particle size favored the sorption of MPs and simulated weathering enhanced sorption on MPs with medium/high Tg. As for desorption, slight hysteresis was observed in most cases with near-zero hysteresis index (HI), and PHE generally had higher HI than 1-Nnap. The simulated digestive solution could further promote the desorption of PHE. The PHE concentrations in earthworms with the presence of 5% PBS or PP MPs in soil were 1.50-2.35 or 1.59-1.75 times that of the control without MPs; and PBS MPs with the smallest particle size showed the greatest enhancement. The results of this study confirmed that polar MPs could strongly but reversibly sorb both polar and nonpolar OCs and hence promote the bioaccumulation of OCs to soil organisms.

13.
J Colloid Interface Sci ; 607(Pt 1): 68-75, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34492355

RESUMEN

Metallic vanadium dichalcogenides with high conductivity and large layer spacing are fantastically potential to be cathode candidates for aqueous zinc ion batteries. However, simply reliance on the reversible Zn2+ intercalation/deintercalation process in the layer structure of vanadium dichalcogenides makes it suffer from low specific capacity and limited cycling number. Here we report a facile in-situ electrochemical oxidation strategy to boost the zinc ion storage capacity of interlayer-expanded vanadium disulfide (VS2·NH3) hollow spheres with satisfying cyclic stability. The hydrated vanadium oxide (V2O5·nH2O) generated from oxidized VS2·NH3, are endowed with reduced nanosheet size and subordinated porous structure, which provides abundant accessible sites and accelerates the zinc ion diffusion process. As a result, the VS2·NH3 derived cathode after the electrochemical oxidation process delivers a high reversible capacity of 392 mA h g-1 at 0.1 A g-1 and long cyclic stability (110% capacity retention at 3 A g-1 after 2000 cycles). The efficient oxidation process of VS2·NH3 cathode and the storage mechanism in the subsequent cycles are schematically investigated. This work not only reveals the zinc ion storage mechanism of the oxidized VS2·NH3 but also sheds light on advanced design for high-performance Zn ion cathode materials.

14.
J Colloid Interface Sci ; 607(Pt 1): 219-228, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34500421

RESUMEN

In this work, Molybdenum (Mo) doped bismuth vanadate (BiVO4) is carried out by traditional calcination method, while carbon-based cobalt (Co-Ci) is prepared by photoelectric deposition (PED) and used as co-catalyst to decorate the surface, its photocurrent density reached 3.15 mA/cm2 at 1.23 V vs RHE. More importantly, the H-Co-Ci/Mo: BiVO4 photoanode obtained by plasma etching of Co-Ci/Mo: BiVO4 has greatly improved surface hydrophilicity. The photocurrent density of H-Co-Ci/Mo: BiVO4 photoanode is 4.8 times that of BiVO4 photoanode, reaching 3.95 mA/cm2. In addition, the incident photon-current conversion efficiency (IPCE) value of the H-Co-Ci/Mo: BiVO4 photoanode is as high as 60%, and both the injection and separation efficiency have also been enhanced. The enhanced photoelectrochemical (PEC) performance is attributed to the good wettability of the material surface and improvement of water oxidation kinetics. These findings provide a mild and efficient modification method for improving BiVO4 used for water splitting, and are expected to provide new ideas for other photoanodes.

16.
Chem Eng J ; 429: 132332, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34539223

RESUMEN

The ongoing outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has highlighted that new diagnosis technologies are crucial for controlling the spread of the disease. Especially in the resources-limit region, conveniently operated detection methods such as "naked-eye" detection are urgently required that no instrument is needed. Herein, we have designed a novel and facile strategy to fabricate covalent organic framework (COF) capsules, which can be utilized to establish a new colorimetric assay for naked-eye detection of SARS-CoV-2 RNA. Specifically, we employ the digestible ZIF-90 as the sacrificial template to prepare the hollow COF capsules for horseradish peroxidase (HRP) encapsulation. The fabricated COF capsules can provide an appropriate microenvironment for the enzyme molecules, which may improve the conformational freedom of enzymes, enhance the mass transfer, and endow the enzyme with high environmental resistance. With such design, the proposed assay exhibits outstanding analytical performance for the detection of SARS-CoV-2 RNA in the linear range from 5 pM to 50 nM with a detection limit of 0.28 pM which can go parallel to qTR-PCR analysis. Our method also possesses excellent selectivity and reproducibility. Moreover, this method can also be served to analyze the clinical samples, and can successfully differentiate COVID-19 patients from healthy people, suggesting the promising potential in clinical diagnosis.

17.
Bioact Mater ; 8: 140-152, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34541392

RESUMEN

Magnesium (Mg) alloys that have both antibacterial and osteogenic properties are suitable candidates for orthopedic implants. However, the fabrication of ideal Mg implants suitable for bone repair remains challenging because it requires implants with interconnected pore structures and personalized geometric shapes. In this study, we fabricated a porous 3D-printed Mg-Nd-Zn-Zr (denoted as JDBM) implant with suitable mechanical properties using selective laser melting technology. The 3D-printed JDBM implant exhibited cytocompatibility in MC3T3-E1 and RAW267.4 cells and excellent osteoinductivity in vitro. Furthermore, the implant demonstrated excellent antibacterial ratios of 90.0% and 92.1% for methicillin-resistant S. aureus (MRSA) and Escherichia coli, respectively. The 3D-printed JDBM implant prevented MRSA-induced implant-related infection in a rabbit model and showed good in vivo biocompatibility based on the results of histological evaluation, blood tests, and Mg2+ deposition detection. In addition, enhanced inflammatory response and TNF-α secretion were observed at the bone-implant interface of the 3D-printed JDBM implants during the early implantation stage. The high Mg2+ environment produced by the degradation of 3D-printed JDBM implants could promote M1 phenotype of macrophages (Tnf, iNOS, Ccl3, Ccl4, Ccl5, Cxcl10, and Cxcl2), and enhance the phagocytic ability of macrophages. The enhanced immunoregulatory effect generated by relatively fast Mg2+ release and implant degradation during the early implantation stage is a potential antibacterial mechanism of Mg-based implant. Our findings indicate that 3D-printed porous JDBM implants, having both antibacterial property and osteoinductivity, hold potential for future orthopedic applications.

18.
Bioact Mater ; 8: 165-176, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34541394

RESUMEN

A spatiotemporally dynamic therapy (SDT) is proposed as a powerful therapeutic modality that provides spatially dynamic responses of drug-carriers for adapting to the wound microenvironment. Herein, dynamic chitosan-poly (ethylene glycol) (CP) Schiff-base linkages are employed to perform SDT by directly converting a liquid drug Kangfuxin (KFX) into a gel formation. The obtained KFX-CP drug-gel with shape-adaptive property is used to treat a representative oral mucositis (OM) model in a spatiotemporally dynamic manner. The KFX-CP drug-gel creates an instructive microenvironment to regulate signaling biomolecules and endogenous cells behavior, thereby promoting OM healing by the rule of dynamically adjusting shape to fit the irregular OM regions first, and then provides space for tissue regeneration, over KFX potion control and the general hydrogel group of CP hydrogel and KFX-F127. Most interestingly, the regenerated tissue has ordered structure like healthy tissue. Therefore, the SDT provides a new approach for the design of next generation of wound dressing and tissue engineering materials.

19.
Chemosphere ; 286(Pt 1): 131543, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34303045

RESUMEN

Heavy metal ions in chelated forms have aroused great concerns because of their high solubility, poor biodegradation and extreme stability. In this research, an efficient strategy, interior microelectrolysis-Fenton-recycle ferrite (IM-Fenton-RF), was developed to treat simulated electroplating wastewater containing chelated copper at room temperature. The decomplexation of chelated copper was carried out by both interior microelectrolysis and Fenton reactions. IM process can not only partly degrade the complexes of chelated copper via the microelectrolysis reaction but also it produces Fe2+ ions for the Fenton reaction. After decomplexation, the IM-Fenton effluent directly flowed into the RF reactor for copper ions removal. Under optimum reaction conditions (reflux ratio = 0.37, Fe2+ concentration = 9.20 g/L at pH 10.18), 99.9% copper was removed by the IM-Fenton-RF system. The produced IM-Fenton-RF sludge is based on ferrite precipitate and has several advantages over metal hydroxides sludge. Ferrite sludge is stable owing to the stability of ferrite's crystal structure, while the toxicity characteristic leaching procedure (TCLP) test meets relevant standards. The sedimentation rate and volume of ferrite sludge were 3.86 times faster and 11.0 times lower than those of metal hydroxides sludge. Furthermore, the yielding sludge of ferrite can be recovered and utilized for the synthesis of Fe-C metallic species, the main compound of IM packing for interior microelectrolysis reaction. All these results show that a combination of IM-Fenton and RF is an effective approach to treat wastewater containing chelated copper, showing great potential for industrial applications.


Asunto(s)
Metales Pesados , Aguas Residuales , Galvanoplastia , Compuestos Férricos
20.
J Colloid Interface Sci ; 606(Pt 2): 1874-1881, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34530184

RESUMEN

Developing efficient and cost-effective catalysts for hydrogen evolution reaction (HER) is vital to hydrogen energy's commercial applications. In this study, N,P-doped carbon supported ruthenium (Ru) doped triruthenium tetraphosphide (Re3P4) (Ru-Re3P4/NPC) with porous nanostructure is prepared using the low-toxic melamine phosphate as the carbon and phosphorous source. The in-situ generated N,P-doped carbon layers play a pivotal role in regulating the electrocatalytic activity by avoiding the aggregation of the nanoparticles and increasing the specific surface area. Moreover, Ru doping contributes to the remarkable electrocatalytic performance of the prepared nanomaterials. Impressively, the as-synthesized Ru-Re3P4/NPC presents remarkable electrocatalytic performances toward HER with small overpotentials of 39 mV, 115 mV, and 88 mV to deliver 10 mA cm-2 in alkaline, neutral, and acidic media. Moreover, the prepared electrocatalyst can drive water-splitting with a small potential of 1.45 V@10 mA cm-2 and use sustainable energies, including solar, wind, and thermal, as electric resources. This work paves a novel and valuable way to enhance the electrocatalytic performances of metal phosphides.

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