Enhanced tetracycline degradation by novel Mn-FeOOH/CNNS photocatalysts in a visible-light-driven photocatalysis coupled peroxydisulfate system.

Recently, photocatalysis combined peroxydisulfate activation under visible light (PC-PDS/Vis) was developed as a promising technology for removing antibiotics in water. Herein, Mn doped FeOOH (Mn-FeOOH) nanoclusters were grown in-situ on the surface of graphitic carbon nitride nanosheets (CNNS) using a wet chemical method, which served as a visible-light-driven photocatalyst for peroxydisulfate (PDS) activation. Photovoltaic property characterizations revealed that Mn-FeOOH/CNNS owned superior light capture ability and carrier separation efficiency. According to DFT calculations, the synergistic effect between Mn and Fe species was proved to enhance the adsorption and activation of PDS. 99.7% of tetracycline (TC) was rapidly removed in 50 min in the PC-PDS/Vis system. In addition, Mn-FeOOH/CNNS exhibited high recycling stability with low iron leaching, attributed to the interaction between Mn-FeOOH clusters and carbon species. Quenching experiments and electron spin resonance (ESR) tests unveiled that •O2- played a significant role in TC removal, while •OH and SO4•- acted as additional roles contributing to the overall process. These findings given a new strategy for antibiotics degradation by photocatalysis, offering deeper insights for the advancement of sustainable and cutting-edge wastewater treatment technologies.

NIR-II Light-Driven Genetically Engineered Exosome Nanocatalysts for Efficient Phototherapy against Glioblastoma.

Glioblastoma (GBM) poses a significant therapeutic challenge due to its invasive nature and limited drug penetration through the blood-brain barrier (BBB). In response, here we present an innovative biomimetic approach involving the development of genetically engineered exosome nanocatalysts (Mn@Bi2Se3@RGE-Exos) for efficient GBM therapy via improving the BBB penetration and enzyme-like catalytic activities. Interestingly, a photothermally activatable multiple enzyme-like reactivity is observed in such a nanosystem. Upon NIR-II light irradiation, Mn@Bi2Se3@RGE-Exos are capable of converting hydrogen peroxide into hydroxyl radicals, oxygen, and superoxide radicals, providing a peroxidase (POD), oxidase (OXD), and catalase (CAT)-like nanocatalytic cascade. This consequently leads to strong oxidative stresses to damage GBM cells. In vitro, in vivo, and proteomic analysis further reveal the potential of Mn@Bi2Se3@RGE-Exos for the disruption of cellular homeostasis, enhancement of immunological response, and the induction of cancer cell ferroptosis, showcasing a great promise in anticancer efficacy against GBM with a favorable biosafety profile. Overall, the success of this study provides a feasible strategy for future design and clinical study of stimuli-responsive nanocatalytic medicine, especially in the context of challenging brain cancers like GBM.

Preparation of expandable vertically aligned carbon nanotube arrays/polydimethylsiloxane membrane by a modular splicing method and its application in in situ ethanol recovery from ethanol fermentation.

Aligned carbon nanotube (CNT) arrays have been widely used in the preparation of polymer composites. CNT arrays are commonly prepared by chemical vapor deposition (CVD) in a high temperature tubular furnace, and the areas of the aligned CNT/polymer membranes prepared are relatively small (<30 cm2) due to the limitation of the inner diameter of the furnace, which limits its practical application in the field of membrane separation. Herein, the vertically aligned CNT arrays/polydimethylsiloxane (PDMS) membrane with large and expandable area was prepared by a modular splicing method for the first time, with a maximum area of 144 cm2. The addition of CNT arrays with openings at both ends significantly improved the pervaporation performance of the PDMS membrane for ethanol recovery. At 80 °C, the flux (671.6 g m-2 h-1) and separation factor (9.0) of CNT arrays/PDMS membrane were increased by 435.12% and 58.52%, respectively, compared with those of the PDMS membrane. Furthermore, the expandable area enabled the CNT arrays/PDMS membrane to couple with fed-batch fermentation for pervaporation for the first time, which increased the ethanol yield (0.47 g g-1) and productivity (2.34 g L-1 h-1) by 9.3% and 4.9% respectively compared with batch fermentation. Besides, the flux (135.47-166.79 g m-2 h-1) and separation factor (8.83-9.21) of CNT arrays/PDMS membrane remained stable in this process, indicating that this membrane has the potential to be applied in industrial bioethanol production. This work provides a new idea for the preparation of large-area aligned CNT/polymer membranes, and also opens up a new direction for the application of large-area aligned CNT/polymer membranes.

Construction of 2D/2D Mesoporous WO3/CeO2 Laminated Heterojunctions for Optimized Photocatalytic Performance.

Photocatalytic elimination of antibiotics from the environment and drinking water is of great significance for human health. However, the efficiency of photoremoval of antibiotics such as tetracycline is severely limited by the prompt recombination of electron holes and slow charge migration efficacy. Fabrication of low-dimensional heterojunction composites is an efficient method for shortening charge carrier migration distance and enhancing charge transfer efficiency. Herein, 2D/2D mesoporous WO3/CeO2 laminated Z-scheme heterojunctions were successfully prepared using a two-step hydrothermal process. The mesoporous structure of the composites was proved by nitrogen sorption isotherms, in which sorption-desorption hysteresis was observed. The intimate contact and charge transfer mechanism between WO3 nanoplates and CeO2 nanosheets was investigated using high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy measurements, respectively. Photocatalytic tetracycline degradation efficiency was noticeably promoted by the formation of 2D/2D laminated heterojunctions. The improved photocatalytic activity could be attributed to the formation of Z-scheme laminated heterostructure and 2D morphology favoring spatial charge separation, confirmed by various characterizations. The optimized 5WO3/CeO2 (5 wt.% WO3) composites can degrade more than 99% of tetracycline in 80 min, achieving a peak TC photodegradation efficiency of 0.0482 min-1, which is approximately 3.4 times that of pristine CeO2. A Z-scheme mechanism is proposed for photocatalytic tetracycline by from WO3/CeO2 Z-scheme laminated heterojunctions based on the experimental results.

Efficient Charge Transfer Channels in Reduced Graphene Oxide/Mesoporous TiO2 Nanotube Heterojunction Assemblies toward Optimized Photocatalytic Hydrogen Evolution.

Interface engineering is usually considered to be an efficient strategy to promote the separation and migration of photoexcited electron-hole pairs and improve photocatalytic performance. Herein, reduced graphene oxide/mesoporous titanium dioxide nanotube heterojunction assemblies (rGO/TiO2) are fabricated via a facile hydrothermal method. The rGO is anchored on the surface of TiO2 nanosheet assembled nanotubes in a tightly manner due to the laminated effect, in which the formed heterojunction interface becomes efficient charge transfer channels to boost the photocatalytic performance. The resultant rGO/TiO2 heterojunction assemblies extend the photoresponse to the visible light region and exhibit an excellent photocatalytic hydrogen production rate of 932.9 µmol h-1 g-1 under simulated sunlight (AM 1.5G), which is much higher than that of pristine TiO2 nanotubes (768.4 µmol h-1 g-1). The enhancement can be ascribed to the formation of a heterojunction assembly, establishing effective charge transfer channels and favoring spatial charge separation, the introduced rGO acting as an electron acceptor and the two-dimensional mesoporous nanosheets structure supplying a large surface area and adequate surface active sites. This heterojunction assembly will have potential applications in energy fields.

Polydopamine/defective ultrathin mesoporous graphitic carbon nitride nanosheets as Z-scheme organic assembly for robust photothermal-photocatalytic performance.

Polydopamine/defective ultrathin mesoporous graphitic carbon nitride (PDA/DCN) Z-scheme organic assembly is fabricated through high-temperature surface hydrogenation and ultrasonic freeze-dried strategies. PDA could be anchored on the surface of DCN with adequate N-vacancy defects firmly via π-π interactions, forming Z-scheme heterogenous structure for promoting charge separation. The visible and near-infrared light driven photocatalytic hydrogen evolution rate is up to 3420 µmol h-1 g-1, and the removal ratio of organic contaminant methylene blue is up to 98% within 70 min, which is several times higher than that of pristine graphitic carbon nitride and DCN. The important reason is the defects of DCN not only enhance the interaction with PDA, but also make the obvious polarized inbuilt electric field, and lead to Z-scheme structure for effective charge separation and rapid transfer, which is also confirmed by density functional theory (DFT) calculations. In addition, PDA extends the photoresponse to the near-infrared region and induces obvious photothermal effect to increase the reaction rate of the photocatalytic system. The efficient photothermal conversion of PDA/DCN should be another reason for the enhanced photocatalytic performance.

Heptadecanoic acid and pentadecanoic acid crosstalk with fecal-derived gut microbiota are potential non-invasive biomarkers for chronic atrophic gastritis.

Background: Chronic atrophic gastritis (CAG), premalignant lesions of gastric cancer (GC), greatly increases the risk of GC. Gastroscopy with tissue biopsy is the most commonly used technology for CAG diagnosis. However, due to the invasive nature, both ordinary gastroscope and painless gastroscope result in a certain degree of injury to the esophagus as well as inducing psychological pressure on patients. In addition, patients need fast for at least half a day and take laxatives. Methods: In this study, fecal metabolites and microbiota profiles were detected by metabolomics and 16S rRNA V4-V5 region sequencing. Results: Alteration of fecal metabolites and microbiota profiles was found in CAG patients, compared with healthy volunteers. To identify the most relevant features, 7 fecal metabolites and 4 microbiota were selected by random forest (RF), from A and B sample sets, respectively. Furthermore, we constructed support vector machines (SVM) classifification model using 7 fecal metabolites or 4 gut microbes, or 7 fecal metabolites with 4 gut microbes, respectively, on C sample set. The accuracy of classifification model was 0.714, 0.857, 0.857, respectively, and the AUC was 0.71, 0.88, 0.9, respectively. In C sample set, Spearman's rank correlation analysis demonstrated heptadecanoic acid and pentadecanoic acid were signifificantly negatively correlated to Erysipelotrichaceae_UCG-003 and Haemophilus, respectively. We constructed SVM classifification model using 2 correlated fecal metabolites and 2 correlated gut microbes on C sample set. The accuracy of classification model was 0.857, and the AUC was 0.88. Conclusion: Therefore, heptadecanoic acid and pentadecanoic acid, crosstalk with fecal-derived gut microbiota namely Erysipelotrichaceae_UCG-003 and Haemophilus, are potential non-invasive biomarkers for CAG diagnosis.

Effective isolation of Sertoli cells from New Zealand rabbit testis.

OBJECTIVE: Sertoli cells (SCs) are important sustentacular cells in the seminiferous tubules of the testis. Isolation and identification of SCs are the premise for studying their functions. Since New Zealand rabbit is a stable strain which is widely used for biomedical research and animal farming, this study aimed to develop a simple and effective protocol for SC isolation in New Zealand rabbits. MATERIALS AND METHODS: The SCs of three 30-day-old New Zealand rabbits were isolated by incubation with enzymatic digestion I (Dulbecco's modified Eagle medium supplemented with 1 mg/ml collagenase IV and 50 µg/ml DNase I) and digestion II (digestion I + 1 mg/ml hyaluronidase + 1 mg/ml trypsin), as well as differential plating. The cells were enriched and identified by using immunocytochemical staining and reverse transcription polymerase chain reaction analysis. RESULTS: Homogeneous cells were obtained. They presented the typical large cell body and an irregular pyramidal shape after differential plating and passaging. These cells expressed mRNA of the SC marker sex-determining region Y-box 9 (SOX9) instead of the Leydig cell marker StAR. Immunocytochemically, they are positive of SOX9, GATA binding protein 4, and androgen-binding protein. CONCLUSION: The SCs were enriched from the testicular tissues of prepubertal New Zealand rabbits by a simple and effective protocol, which provides a basis for further theoretical researches and practical applications.

Efficacy of Banxia Xiexin decoction for chronic atrophic gastritis: A systematic review and meta-analysis.

BACKGROUND: Banxia Xiexin decoction (BXD), a classical formula of traditional Chinese medicine (TCM), has been wildly used for chronic atrophic gastritis (CAG) patients with the cold-heat complex syndrome in China, and achieved satisfied effects. However, the clinical effects of it remains unclear. PURPOSE: The purpose of this article is to evaluate the clinical efficacy and safety of BXD for CAG treatment. METHODS: We searched seven electronic databases including Ovid, Embase, PubMed, Cochrane Library, Wan-fang database, VIP (Chinese Scientific Journals Database) and CNKI (China National Knowledge Infrastructure) from their inception to September 21, 2020. We used Jadad scale and Cochrane Collaboration's risk of bias tool to make evaluation of methodological quality. Revman 5.3 statistical software was used for statistical processing to evaluate the clinical efficacy and safety of BXD. RESULTS: 26 randomized controlled trials (RCTs) totaling 1985 patients were identified for analysis. Meta-analysis showed that BXD treatment was more effective (RR 1.29; 95%CI 1.24, 1.35; P<0.00001) and safe (MD 0.33; 95%CI 0.18, 0.58; P = 0.0002) than Chinese patent medicine + western medicine. Furthermore, BXD had improvement on symptoms scores such as stomach distending pain, and belching. Besides, BXD was more effective in inhibiting Helicobacter Pylori (HP), improving HP-related inflammation, and relieving the degree of glandular atrophy, intestinal metaplasia (IM), and dysplasia of gastric mucosa (GM). CONCLUSIONS: The meta-analysis showed that BXD was more effective and safer for CAG patients than the control group. However, due to limitations of methodological quality and small sample size of the included studies, further standardized research of rigorous design should be needed.

VMD-based denoising methods for surface electromyography signals.

OBJECTIVE: Since noise is inevitably introduced during the measurement process of surface electromyographic (sEMG) signals, two novel methods for denoising based on the variational mode decomposition (VMD) method were proposed in this work. Prior to this study, there has been no literature relating to how VMD is applied to sEMG denoising. APPROACH: The first proposed method uses the VMD method to decompose the signal into multiple variational mode functions (VMFs), each of which has its own center frequency and narrow band, and then the wavelet soft thresholding (WST) method is applied to each VMF. This method is termed the VMD-WST. The second proposed method uses the VMD method to decompose the signal into multiple VMFs, and then the soft interval thresholding (SIT) method is performed on each VMF, which is abbreviated as VMD-SIT. Ten healthy subjects and ten stroke patients participated in the experiment, and the sEMG signals of bicep brachii were measured and analyzed. In this paper, three methods are used for quantitative evaluation of the filtering performance: the signal-to-noise ratio (SNR), root mean square error and R-squared value. The proposed two methods (VMD-WST, VMD-SIT) are compared with the empirical mode decomposition (EMD) method and the wavelet method. MAIN RESULTS: The experimental results showed that the VMD-WST and VMD-SIT methods can effectively filter the noise effect, and the denoising effects were better than the EMD method and the wavelet method. The VMD-SIT method has the best performance. SIGNIFICANCE: This study provides a new means of eliminating the noise of sEMG signals based on the VMD method, and it can be applied in the fields of limb movement classification, disease diagnosis, human-machine interaction and so on.

Tuned Fabrication of the Aligned and Opened CNT Membrane with Exceptionally High Permeability and Selectivity for Bioalcohol Recovery.

Synthetic membranes usually suffer from a ubiquitous trade-off between permeability and selectivity. Carbon nanotube (CNT)-based hybrid materials have shown attractive properties in high-performance membrane preparation; however, the aggregation of random CNTs in polymer remains a great challenge. Herein, the aligned and open-ended CNT/(polydimethylsiloxane) PDMS membranes are controllably fabricated to form a hamburger-like structure that possesses nanochannels (∼10 nm) in the intermediate layer as well as angstrom cavities in the embedded PDMS. These aligned CNT membranes surpass the filling content limitation of the nonaligned CNT/PDMS membrane (37.4 wt % versus ∼10 wt %), leading to excellent mechanical properties and a multiplying performance increase of mass flux and selectivity for the separation of alcohols. The membranes break the permeability-selectivity trade-off with both parameters remarkably increasing (maximum 9 times) for bioalcohol separation. The established pervaporative-ultrafiltration mechanism indicates that the penetrant molecules preferentially pass through CNT internal nanochannels with increasing membrane permeability, thereby paving a way to nanoscale design of highly efficient channeled membranes for separation application.

Evaluation of hydrophobic micro-zeolite-mixed matrix membrane and integrated with acetone-butanol-ethanol fermentation for enhanced butanol production.

BACKGROUND: Butanol is regarded as an advanced biofuel that can be derived from renewable biomass. However, the main challenge for microbial butanol production is low butanol titer, yield and productivity, leading to intensive energy consumption in product recovery. Various alternative separation technologies such as extraction, adsorption and gas stripping, etc., could be integrated with acetone-butanol-ethanol (ABE) fermentation with improving butanol productivity, but their butanol selectivities are not satisfactory. The membrane-based pervaporation technology is recently attracting increasing attention since it has potentially desirable butanol selectivity. RESULTS: The performance of the zeolite-mixed polydimethylsiloxane (PDMS) membranes were evaluated to recover butanol from butanol/water binary solution as well as fermentation broth in the integrated ABE fermentation system. The separation factor and butanol titer in permeate of the zeolite-mixed PDMS membrane were up to 33.0 and 334.6 g/L at 80°C, respectively, which increased with increasing zeolite loading weight in the membrane as well as feed temperature. The enhanced butanol separation factor was attributed to the hydrophobic zeolites with large pore size providing selective routes preferable for butanol permeation. In fed-batch fermentation incorporated with pervaporation, 54.9 g/L ABE (34.5 g/L butanol, 17.0 g/L acetone and 3.4 g/L ethanol) were produced from 172.3 g/L glucose. The overall butanol productivity and yield increased by 16.0 and 11.1%, respectively, which was attributed to the alleviated butanol inhibition by pervaporation and reassimilation of acids for ABE production. The zeolite-mixed membrane produced a highly concentrated condensate containing 169.6 g/L butanol or 253.3 g/L ABE, which after phase separation easily gave the final product containing >600 g/L butanol. CONCLUSIONS: Zeolite loading in the PDMS matrix was attributed to improving the pervaporative performance of the membrane, showing great potential to recover butanol with high purity. Therefore, this zeolite-mixed PDMS membrane had the potential to improve biobutanol production when integrating with ABE fermentation.

Negative interference by rheumatoid factor of plasma B-type natriuretic peptide in chemiluminescent microparticle immunoassays.

BACKGROUND: The chemiluminescent microparticle immunoassay (CMIA) is widely used for the quantitative determination of B-type natriuretic peptide (BNP) in human ethylenediaminetetraacetic acid plasma. Rheumatoid factor (RF) is usually thought to result in a positive interference in immunoassays, but it is not clear whether its presence in plasma can lead to interferences in the CMIA of BNP. METHODS: The estimation of BNP recovery was carried out by diluting high-concentration BNP samples with RF-positive or RF-negative plasma at a ratio of 1:9. The diluted samples were then tested using the ARCHITECT i2000 System and ARCHITECT BNP Reagent Kits and the recovery was then calculated. RESULTS: When the RF level ranged from 48 to 1420 IU/mL, the average recovery of BNP was 79.29% and 91.61% in the RF-positive and RF-negative plasma samples, respectively, and was thus significantly lower in the group of RF-positive plasma samples than in the group of RF-negative plasma samples. At a dilution of 1:16, the measured BNP level increased by >36% in six of the seven RF-positive plasma samples. The recovery of BNP increased significantly in the RF-positive plasma samples after pretreatment with IgG-sensitive latex particles. In addition, The BNP recovery was not significantly related to the plasma RF at concentrations ranging from 48 to 2720 IU/mL. CONCLUSIONS: Measurement of BNP by CMIA is susceptible to interference from RF leading to predominantly (but not exclusively) lower results. Pretreatment of samples with blocking reagents is advisable prior to the initiation of denying patient's necessary treatment.