Regulating the Morphology Modification To Prepare the High Charge Separation Efficiency and Visible Light Responsive Dual-Type-II B-CN/H-TiO2/BS-CN Heterojunction for Wastewater Treatment.

For the conventional type-II heterojunction photocatalyst, their photocatalytic activity is affected by the limited separation efficiency of electron-hole pairs, exquisitely designed heterojunction photocatalysts are highly prospective materials for inducing charge transfer efficiently. Typically, enhancing the separation efficiency of electron-hole pairs in photocatalysts has been a formidable challenge. Here, the hollow mesoporous TiO2 (H-TiO2), the bulk g-C3N4 (B-CN), and g-C3N4 with bamboo shape (BS-CN) are prepared by simple processes. Among them, it is surprising to find that the band structure of g-C3N4 can be regulated and controlled by adjusting its structure. The B-CN/H-TiO2/BS-CN (CNTOCN) dual-type-II heterojunction photocatalyst and B-CN/H-TiO2 (CNTO) type-II heterojunction photocatalyst are designed to improve the separation efficiency of electron-hole pairs. The superiority of CNTOCN dual-type-II heterojunction photocatalyst is demonstrated by the photocatalysis experiment, the band structure analysis, and the photoelectric characterization. The results show that CNTOCN (0.8428 h-1) has much higher photocatalytic activity than H-TiO2 (0.0812 h-1), B-CN (0.3569 h-1), and CNTO (0.5934 h-1). The improvement of photocatalytic activity is ascribed to the establishment of the dual-type-II heterojunction charge transfer mechanism. This work presents an approach to designing efficient dual-type-II heterojunction photocatalysts for the sustainable conversion of solar energy to photodegrade dyes in dyeing wastewater.

Actinomycin X2, an Antimicrobial Depsipeptide from Marine-Derived Streptomyces cyaneofuscatus Applied as a Good Natural Dye for Silk Fabric.

Actinomycins as clinical medicine have been extensively studied, while few investigations were conducted to discover the feasibility of actinomycins as antimicrobial natural dye contributing to the medical value of the functional fabrics. This study was focused on the application of actinomycin X2 (Ac.X2), a peptide pigment cultured from marine-derived Streptomyces cyaneofuscatus, in the dyeing and finishing of silk fabric. The dyeing potential of Ac.X2 with silk vs. cotton fabrics was assessed. As a result, the silk fabric exhibited greater uptake and color fastness with Ac.X2. Through Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses, some changes of chemical property for the dyed fabric and Ac.X2 were studied. The silk fabric dyed with Ac.X2 exhibited good UV protection ability. The antibacterial properties of dyed and finished silk were also evaluated, which exhibited over 90% antibacterial activity even after 20 washing cycles. In addition, the brine shrimp assay was conducted to evaluate the general toxicity of the tested fabric, and the results indicated that the dyed silk fabrics had a good biological safety property.

Amperometric determination of nitrite by using a nanocomposite prepared from gold nanoparticles, reduced graphene oxide and multi-walled carbon nanotubes.

A nanocomposite consisting of gold nanoparticles (AuNP), reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNTs) was synthesized using a co-reduction strategy in ethylene glycol using sodium citrate as the reducing agent. The nanocomposite was successfully characterized using X-ray powder diffraction, scanning electron microscopy and electrochemical methods. The material was deposited on a glassy carbon electrode and then was found to have high electrocatalytic capability for the electrode process of nitrite. This is attributed to the synergic actions of rGO, MWCNTs and AuNPs. Based on this, an amperometric nitrite sensing scheme was worked out that had attractive features: (a) a wide linear range that extends from 50 nM to 2.2 mM, (b) a working potential of 0.80 V (vs.SCE) at pH 5.0, (c) a 14 nM detection limit (at an SNR of 3), and (d) an electrochemical sensitivity of 1201 µA·mM-1·cm-2. The sensor was successfully applied to the determination of nitrite in the local river water. Graphical abstract Schematic presentation of the fabrication of the AuNPs-rGO-MWCNTs composite modified electrode and its application for the nitrite electrochemical sensing.

Nonsequential double ionization of Mg from a doubly excited complex driven by circularly polarized laser field.

With the classical ensemble method, the correlated-electron dynamics of Mg atom from a doubly excited, transition Coulomb complex in few-cycle circularly polarized (CP) laser field at low laser intensity is theoretically investigated. The low energy transfer during the recollision process indicates that the two electrons cannot release directly, but it can pass through a doubly excited state, and then escape with the ionization time difference. The numerical results show that the feature of the sequential double ionization (SDI) can be observed in the nonsequential double ionization (NSDI) process. The SDI-like results demonstrate that the intermediate state has lost any memory of its formation dynamics. The distribution of the angle between the two release directions of the two electrons also depends on the ionization time difference. Finally, the influence of e-e Coulomb repulsion is discussed.

Multimodal integrated and broadband light-driven antibacterial cellulose fabric based on π-π coupling enhanced intermolecular FRET.

Fabrication of antimicrobial photodynamic therapy (aPDT) materials based on organic photosensitizers has garnered considerable attention within functional textiles. However, the UV- or narrow-band absorption range of the photosensitizers results in poor photon utilization of the fabrics, limiting the photodynamic efficiency and wasting solar energy. In this study, a broadband light-driven antibacterial cellulose fabric (CF-ZnPc/NAD) was developed by loading carboxyl-modified zinc(II) phthalocyanine photosensitizer (CAZnPc) and cationic 1,8-naphthalimide fluorescent molecule (NAD) on the fabric via covalent binding and electrostatic adsorption assembly, facilitating the intermolecular π-π coupling and fluorescence resonance energy transfer (FRET) process. There is a 2.54-fold increase in photo-induced ROS generation capacity of CF-ZnPc/NAD via the FRET process compared to that of CF-ZnPc, and it also exhibited a strong photothermal effect (PTT), wherein the temperature of the fabric increased from 24.5 to 53.5 °C within 80 s of illumination (λ > 400 nm, 75 mW/cm2). CF-ZnPc/NAD exhibited strong light-harvesting capacity and a combination of aPDT and PTT, achieving excellent antibacterial performance against Staphylococcus aureus (Gram-positive, S. aureus) and Escherichia coli (Gram-negative, E.coli) with 99.99 % bacterial reduction under 90 min of illumination (λ > 400 nm, 10 ± 1 mW/cm2). This study demonstrates a novel and facile strategy for successfully fabricating high-performance antibacterial cellulose fabrics with potential biomedical prospects.

Regulating Alkyl Chain Length on Quaternization TiO2 for Boosting Photocatalytic Performance: Synergism of Promoting Photogenerated Charge Separation and Improving Reactant Adsorption.

To explore the effect of surface charge properties of a photocatalyst on photocatalytic activity, quaternization TiO2 particles with different alkyl chain lengths (CT-X/P25) are first synthesized to boost the photocatalytic activity. The effect of a quaternary ammonium group with different alkyl chain lengths on the photocatalytic activity of CT-X/P25 is investigated. Interestingly, the introduction of a quaternary ammonium group on CT-X/P25 not only contributes to improving the photodegradation efficiency of anionic dyes due to enhancing of adsorption capacity through electrostatic attraction, but also it can improve the photodegradation efficiency of cationic dyes. Therefore, there seems to be another factor affecting the photocatalytic activity. The results of photoelectric characterization show that the photogenerated charge separation of CT-X/P25 is greatly enhanced, which is beneficial to improve the photocatalytic activity. Simultaneously, the results show that the difference in the photocatalytic activity of CT-X/P25 is mainly related to the charge intensity of -N+(CH3)2- in the quaternary amine salt. According to X-ray photoelectron spectroscopy, the charge intensity of -N+(CH3)2- in CT-X/P25 gradually increases with the increase in alkyl chain lengths, which is conducive to promoting photogenerated charge separation and improving the adsorption for anionic dyes. The photocatalytic activity has been further enhanced due to the enhancement of this synergy. In summary, the quaternary ammonium salt-modified CT-X/P25 shows an excellent synergistic effect on the process of photodegradation of anionic dyes: promoting photogenerated charge separation and adsorption.

Preliminary therapeutic and mechanistic evaluation of S-allylmercapto-N-acetylcysteine in the treatment of pulmonary emphysema.

The objective of this work was to study the effects and mechanisms of S-allylmercapto-N-acetylcysteine (ASSNAC) in the treatment of pulmonary emphysema based on network pharmacology analysis and other techniques. Firstly, the potential targets associated with ASSNAC and COPD were integrated using public databases. Then, a protein-protein interaction network was constructed using String database and Cytoscape software. The Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis were performed on DAVID platform. The molecular docking of ASSNAC with some key disease targets was implemented on the SwissDock platform. To verify the results of the network pharmacology, a pulmonary emphysema mice model was established and treated with ASSNAC. Besides, the expressions of the predicted targets were detected by immunohistochemistry, Western blot analysis or enzyme-linked immunosorbent assay. Results showed that 33 overlapping targets are achieved, including CXCL8, ICAM1, MAP2K1, PTGS2, ACE and so on. The critical pathways of ASSNAC against COPD involved arachidonic acid metabolism, chemokine pathway, MAPK pathway, renin-angiotensin system, and others. Pharmacodynamic experiments demonstrated that ASSNAC decreased the pulmonary emphysema and inflammation in the pulmonary emphysema mice. Therefore, these results confirm the perspective of network pharmacology in the target verification, and indicate the treatment potential of ASSNAC against COPD.

Fabrication of mechanical robust keratin film by mesoscopic molecular network reconstruction and its performance for dye removal.

Regenerated keratin-based adsorbents have attracted much attention in environmental pollution remediation. However, fabricating keratin-based adsorbents with excellent adsorption performance is still a challenging issue due to its weak mechanical property. In this study, mechanical robust keratin composite films were designed and engineered at mesoscopic scale by molecular network reconstruction strategy. It was found that the ß-crystallites structure of silk fibroin template could induce the transformation of free unfolded molecular chains of keratin to ß-sheet conformation and further resulted in the controllable manipulating of the mechanical properties of keratin films. This mechanical reinforced composite film showed high adsorption efficiency and capacity for dyes as well as ideal regeneration and recycling performance. Adsorption behavior of reactive brilliant blue KN-R by keratin composite films was comprehensively studied. The adsorption capacity (qe) and removal efficiency for KN-R by the adsorbent could reach as high as 190.84 mg/g and 98.52%, respectively. The adsorbent exhibited excellent regeneration and recycling performance due to its mechanical robustness. The molecular network reconstruction strategy is both straightforward and effective for fabricating mechanical robust adsorbent for pollutant remediation.

Fabrication of mechanical robust keratin adsorbent by induced molecular network transition and its dye adsorption performance.

Keratin-based adsorbents showed a great potential in environmental pollution remediation. However, fabrication of keratin adsorbent with an excellent performance remains a challenging issue mainly because of its poor mechanical properties. In this research, mechanical-reinforced keratin adsorbent was designed and engineered at mesoscopic scale by the induced molecular network transition method. It was found that the ß-crystallite structure of silk fibroin template could induce the transformation of free unfolded molecular chains of keratin to ß-sheet conformation in the keratin adsorbent and further resulted in the controllable manipulation of the mechanical properties of the adsorbent. The prepared keratin adsorbent exhibited an excellent adsorption performance for Reactive Black 5 (RB5). The qe and removal efficiency for RB5 by the adsorbent could reach as high as 550 mg/g and 95.3%, respectively. The adsorbent exhibited an excellent regeneration and recycle performance due to its mechanical reinforcement. The facile molecular network-induced reconstruction strategy is both straightforward and effective for fabricating mechanical robust adsorbent for environmentally pollutant remediation. Graphical abstract.

Fabrication of a novel functional CNC cross-linked and reinforced adsorbent from feather biomass for efficient metal removal.

In this research, an innovative biomass derived spongy adsorbent was fabricated by adopting dialdehyde cellulose nanocrystals (DCNC) as crosslinking and reinforcing building block, which showed high mechanical strength, satisfying adsorption performance and good recyclability. The improved shape integrity and specific surface area resulted from DCNC incorporation contribute to high adsorption performance of this sponge. Adsorption behaviors of the adsorbent were comprehensively studied. The qe for Pb2+ and Cd2+ by the adsorbent could reach as high as 767 and 517 mg/g, respectively. Also, this adsorbent showed excellent recyclability. In addition, the adsorbent exhibited satisfying fixed-bed column adsorption performance. Thus, it could be considered as promising high efficiency adsorbent.

p38 MAP kinase pathway and stromelysin regulation in trabecular meshwork cells.

PURPOSE: Increased expression of stromelysin-1 (matrix metalloproteinase [MMP]-3) by the trabecular meshwork (TM) initiates extracellular matrix turnover and increases aqueous humor outflow facility. Tumor necrosis factor (TNF)alpha and interleukin (IL)-1alpha are efficacious inducers of MMP-3 in TM. To facilitate understanding of the regulation of MMP-3, the authors investigated the involvement of p38 MAP kinase pathway proteins in this process. METHODS: Western immunoblots were used to determine the effects of these cytokines and p38 MAP kinase pathway inhibitors on MMP-3 protein levels, p38 MAP kinase isoforms, and phosphorylation levels in human and porcine TM cells. The effects of a dominant-negative p38 MAP kinase construct on MMP-3 expression were evaluated. Morphologic changes in the cells were also examined. RESULTS: Both cytokines increased MMP-3 levels. The p38 MAP kinase inhibitor SB202190 diminished MMP-3 induction by TNFalpha at all times and at 24 hours by IL-1alpha but potentiated the IL-1alpha-induced increase in MMP-3 at later times. MMP-3 induction by both cytokines was blocked by dominant-negative p38 MAP kinase constructs. Each cytokine increased phosphorylation of the p38 MAP kinase pathway components and altered TM cell morphology. The p38 inhibitor blocked only the morphologic changes produced by TNFalpha. Human and porcine TM cells expressed p38 alpha, beta, delta, and gamma isoforms, which migrate coincident with bands of specific phosphorylation. CONCLUSIONS: The effects of p38 inhibitors and the dominant-negative construct on TNFalpha and IL-1alpha induction of MMP-3 demonstrate an essential role for p38 in this signaling process. Differences between p38 inhibitor effects on TNFalpha and IL-1alpha induction of MMP-3 suggest divergent p38 isoform use, as do the morphologic responses. The anomalous p38 inhibitor effect on IL-1alpha induction of MMP-3 and phosphorylation of p38 delta/gamma suggests complex interactions between p38 MAP kinase isoforms and their differential uses by TNFalpha and IL-1alpha in TM.

Synergism of TNF and IL-1 in the induction of matrix metalloproteinase-3 in trabecular meshwork.

PURPOSE: TNF and IL-1 increase matrix metalloproteinase-3 (MMP-3) expression in the trabecular meshwork (TM). TNF-alpha, in combination with IL-1alpha or IL-1beta, produces highly synergistic MMP-3 increases. Possible mechanisms for this synergism in TM cells were investigated. METHODS: Porcine and human TM cells were treated with TNF-alpha, IL-1alpha, IL-1beta and their combinations. Western immunoblots were used to evaluate MMP-3, MMP-9, MMP-12, TNF-alpha, IL-1alpha, IL-1beta, IL-6, TNF receptor I (RI), IL-1 RI, and IL-1 RII levels and the phosphorylation of Erk, JNK, and p38 MAP kinases. Dose-response effects for TNF-alpha, IL-1alpha and IL-1beta on MMP-3 were evaluated. Microarray and quantitative RT-PCR were used to determine mRNA levels. MMP-3 transcription rate was assessed by transfecting TM cells with an MMP-3 promoter/reporter construct. Combined cytokine effects on outflow facility were appraised in perfused anterior segment organ culture. RESULTS: TNF-alpha, IL-1alpha, and IL-1beta each individually increased MMP-3 levels, whereas TNF-alpha in combination with IL-1alpha or IL-1beta produced highly synergistic increases. MMP-9 and MMP-12 levels were also elevated, but only MMP-12 showed synergism. IL-1alpha, IL-1beta, and IL-6, but not TNF-alpha mRNA or protein level, were elevated by these cytokines. Maximum MMP-3 production for individual cytokines, even at high doses, was far less than with dual cytokine doses. Erk 1 and 2, JNK 1 and 2, and p38 alpha and beta phosphorylation increased, but not synergistically. However, phosphorylation of novel isoforms of JNK and p38 delta and gamma did show synergism. MMP-3 mRNA levels and transcription rates also demonstrated synergism. TNF-alpha significantly increased IL-1 RI levels. Synergism in outflow facility was observed with TNF-alpha and IL-1alpha. CONCLUSIONS: TNF-alpha, in combination with IL-1alpha or IL-1beta, produced intense synergistic increases in MMP-3 and MMP-12 but not in MMP-9. Induction of IL-1 RI by TNF-alpha partially explains the synergism. Responses of novel JNK and p38 MAP kinase delta and gamma isoforms also partially account for the synergism. Understanding this strong synergistic effect may provide useful insight into optimizing therapeutic regulation of intraocular pressure in glaucoma.

Green and Sustainable Technology for High-Efficiency and Low-Damage Manipulation of Densely Crosslinked Proteins.

A two-step technology using nontoxic and eco-friendly chemicals is developed for the durable setting of densely/highly crosslinked proteins, such as wool and hair. Currently, most technologies for morphological modification are effective only for materials from non-highly-crosslinked proteins and cellulose. Before their morphological change, only water is needed to interrupt hydrogen bonds and ionic linkages, which stabilize the relative positions of molecules in non-highly-crosslinked proteins and cellulose. However, highly crosslinked proteins contain disulfide crosslinks, which are insusceptible to water. Thus, the controlled cleavage of disulfide bonds is required for creating new morphologies of highly crosslinked protein materials, such as hair and wool. Herein, cysteine and citric acid (CA) were used for the two-step setting of highly crosslinked proteins. This recipe showed better morphological change and less mechanical loss than commercial hair styling products. A reaction between CA and keratin was proposed, and verified via NMR and Raman spectra and titration. This technology could be a prospective alternative to achieve durable hair setting, anticrease finishing of wool textiles, and other durable morphological changes needed for highly crosslinked proteins.

Cellulose nanocrystal-reinforced keratin bioadsorbent for effective removal of dyes from aqueous solution.

High-efficiency and recyclable three-dimensional bioadsorbents were prepared by incorporating cellulose nanocrystal (CNC) as reinforcements in keratin sponge matrix to remove dyes from aqueous solution. Adsorption performance of dyes by CNC-reinforced keratin bioadsorbent was improved significantly as a result of adding CNC as filler. Batch adsorption results showed that the adsorption capacities for Reactive Black 5 and Direct Red 80 by the bioadsorbent were 1201 and 1070mgg-1, respectively. The isotherms and kinetics for adsorption of both dyes on bioadsorbent followed the Langmuir isotherm model and pseudo-second order model, respectively. Desorption and regeneration experiments showed that the removal efficiencies of the bioadsorbent for both dyes could remain above 80% at the fifth recycling cycles. Moreover, the bioadsorbent possessed excellent packed-bed column operation performance. Those results suggested that the adsorbent could be considered as a high-performance and promising candidate for dye wastewater treatment.

IL-1 and TNF induction of matrix metalloproteinase-3 by c-Jun N-terminal kinase in trabecular meshwork.

PURPOSE: The cytokines TNF and IL-1 mediate the MMP-3 increase that occurs in response to trabecular meshwork (TM) treatment by laser trabeculoplasty. This MMP-3 increase appears to play a key role in the efficacy of this treatment for open-angle glaucoma. Protein kinase Cmu and the Erk mitogen-activated protein (MAP) kinases are essential signaling components in transducing MMP-3 increases produced by treatment of TM cells with these cytokines. Here, the involvement of the JNK-MAP kinase pathway in this process was evaluated. METHODS: Porcine TM cells were treated with TNFalpha, IL-1alpha, or IL-1beta. Changes in MMP-3 and MMP-9 protein levels in the media were then determined by Western immunoblot. The effect of JNK inhibitor 2 was evaluated. Changes in the level of phosphorylation of JNK, c-Jun, ATF-2, MKK4, and MKK7 were also determined at various times after TNFalpha or IL-1alpha treatment. A 2.3-kb MMP-3 promoter fragment was cloned into a secreted alkaline phosphatase reporter vector. This reporter construct was cotransfected into TM cells with a mammalian expression vector containing a dominant-negative mutant of JNK. The involvement of JNK activity in the TNFalpha and IL-1alpha induction of MMP-3 expression was then evaluated. RESULTS: TNFalpha, IL-1alpha, and IL-1beta increase media MMP-3 and MMP-9 protein levels, and JNK inhibitor 2 blocks these increases. JNK1/2, MKK4, c-Jun, and ATF-2 phosphorylation levels increase in response to TNFalpha and IL-1alpha treatment. JNK inhibitor 2 pretreatment blocks these c-Jun and ATF-2 phosphorylation increases. Dominant-negative JNK dramatically reduces the MMP-3 promoter-driven reporter activity induced by these cytokines. CONCLUSIONS: JNK activity is necessary for the induction of MMP-3 and MMP-9 by TNFalpha, IL-1alpha, or IL-1beta in TM cells. Phosphorylation of components of the JNK signaling pathway and of the transcription factors c-Jun and ATF-2 support a role for this pathway in the induction of MMP-3 and MMP-9 in the TM in response to these cytokines. Thus, at least three separate signal transduction pathways are necessary in this signaling event in TM cells.

Preparation of the superhydrophobic nano-hybrid membrane containing carbon nanotube based on chitosan and its antibacterial activity.

The functional nano-hybrid surface containing multi-walled carbon nanotubes (MWCNT) on chitosan incorporated with the cationic chitosan (C-CS), MWCNTs and silicon couple agent (KH-560) was designed and prepared. The nano-hybrid membranes (NHM) containing MWCNTs were modified by perfluorooctanesulfonyl fluoride (PFOSF). The superhydrophobic multi-functional membranes with biological activity and superhydrophobic surface were obtained. The incorporated MWCNTs improved the roughness of the nano-hybrid membranes. The perfluorinated end groups of the nano-hybrid membrane surface provided low energy surface. The antibacterial activity, surface superhydrophobicity and mechanical property of the perfluorinated nano-hybrid membranes (PFNM) were discussed. Their morphological structures and surface ingredients were characterized by energy dispersive X-ray spectrometer (SEM-EDX). The PFNMs had excellent antibacterial property and superhydrophobicity. The novel nano-hybrid membranes with excellent antibacterial, superhydrophbic, and mechanical properties have potential applications in the food engineering, bioengineering fields and medical materials.

Preparation of multi-functional cellulose containing huge conjugated system and its UV-protective and antibacterial property.

A novel Schiff base containing huge azo conjugated system and reactive groups, 3,5-bis{2-hydroxyphenyl-5-[(2-sulfate-4-sulfatoethylsulfonyl-azobenzol)methylene amino]}benzoic acid (BHSABA) was applied to modify cellulose. Exhaustion and grafting reactive rate, and grafting quantity of BHSABA on cellulose were calculated. The chemical structure of the modified cellulose was characterized and thermal degradation and morphology were also investigated. The UV protection and antibacterial properties were measured. With increasing the concentration of BHSABA, grafting quantity of BHSABA on cellulose increased from 1.52 × 10(-2)mmol/g to 5.08 × 10(-2)mmol/g. The multi-functional cellulose fabrics had excellent UV-protective property, which possessed very high UPF value and very low ultraviolet transmittance. The UPF values exceeded 50 and the ultraviolet transmittances were all less than 1%. They also exhibited moderate activity against Staphylococcus aureus and after 10 times washing still maintained antibacterial activity. The onsets of degradation slightly decreased. With increasing the grafting quantity of BHSABA on cellulose, mass loss yields of the residues increased. The morphological structure had no noticeable change.