Preparation of copolymer 7-hydroxyethyl chrysin loaded PLGA nanoparticles and the in vitro release. / 7-ç¾Ÿä¹™åŸºç™½æ¨ç´ èšä¹³é ¸-ç¾ŸåŸºä¹™é ¸å ±èšç‰©çº³ç±³ç²’çš„åˆ¶å¤‡åŠä½“å¤–é‡Šæ”¾è¯„ä»·.

OBJECTIVES: To prepare 7-hydroxyethyl chrysin (7-HEC) loaded poly (lactic-co-glycolic acid) (PLGA) nanoparticles and to detect the in vitro release. METHODS: The 7-HEC/PLGA nanoparticles were prepared by emulsification solvent volatilization method. The particle size, polydispersity index (PDI), encapsulation rate, drug loading and zeta potential were measured. The prescription was optimized by single factor investigation combined with Box-Behnken response surface method. Mannitol was used as protectant to prepare lyophilized powder, and the optimal formulation was characterized and studied for the in vitro release. RESULTS: The optimal formulation of 7-HEC/PLGA nanoparticles was as follows: drug loading ratio of 2.12∶20, oil-water volume ratio of 1∶14.7, and 2.72% soybean phospholipid as emulsifier. With the optimal formulation, the average particle size of 7-HEC/PLGA nanoparticles was (240.28±0.96) nm, the PDI was 0.25±0.69, the encapsulation rate was (75.74±0.80)%, the drug loading capacity was (6.98±0.83)%, and the potentiostatic potential was (－18.17±0.17) mV. The cumulative in vitro release reached more than 50% within 48 h. CONCLUSIONS: The optimized formulation is stable and easy to operate. The prepared 7-HEC/PLGA nanoparticles have uniform particle size, high encapsulation rate and significantly higher dissolution rate than 7-HEC.

Exploring the mechanism associated with methane emissions during composting: Inoculation with lignocellulose-degrading microorganisms.

Inoculation with microorganisms is an effective strategy for improving traditional composting processes. This study explored the effects of inoculation with lignocellulose-degrading microorganisms (LDM) on the degradation of organic matter (OM), methane (CH4) emissions, and the microbial community (bacteria and methanogens) during composting. The results showed that LDM accelerated the degradation of OM (including the lignocellulose fraction) and increased the CH4 releases in the later thermophilic and cooling stages during composting. At the ending of composting, LDM increased the CH4 emissions by 38.6% compared with the control. Moreover, LDM significantly increased the abundances of members of the bacterial and methanogenic community during the later thermophilic period (P < 0.05). In addition, LDM promoted the growth and activity of major bacterial genera (e.g., Ureibacillus) with the ability to degrade macromolecular OM, as well as affecting key methanogens (e.g., Methanocorpusculum) in the composting system. Network analysis and variance partitioning analysis indicated that OM and temperature were the main factors that affected the bacterial and methanogen community structures. Structural equation modeling demonstrated that the higher CH4 emissions under LDM were related to the growth of methanogens, which was facilitated by the anaerobic environment produced by large amounts of CO2. Thus, aerobic conditions should be improved during the end of the thermophilic and cooling composting period when inoculating with lignocellulose-degrading microorganisms in order to reduce CH4 emissions.

Self-Assembly of Helical Polymers and Oligomers to Create Liquid Crystalline Alignment for Anisotropic NMR Parameters.

The measurement of anisotropic residual dipolar couplings (RDCs) parameters for the structure elucidation of organic molecules relies on suitable alignment media. Employment of self-assembled liquid crystalline systems to create anisotropic alignment can be an effective way to realize aligned samples and acquire RDCs. This Mini-review highlights the recent advances on amino acid-based helical polymers and supramolecular oligomers forming rigid, rod-like structures that aggregate into ordered liquid crystalline phases, including amino acid-based helical polyisocyanides, polyacetylenes, polypeptides, and oligopeptides assembled alignment media. The methodology for the determination of anisotropic liquid crystals is briefly discussed, and a summary of recent research progress in the enantiodifferentiation of helical polymers aligned media is followed. In addition, the self-assembled mechanism of oligopeptides and their RDCs structural analysis are also described.

Evaluating tissue-engineered repair material for pelvic floor dysfunction: a comparison of in vivo response to meshes implanted in rats.

INTRODUCTION AND HYPOTHESIS: Achieving better anatomic restoration and decreasing the associated complications are necessary for material repair of pelvic floor dysfunction (PFD). This study was aimed to investigate host response to tissue-engineered repair material (TERM) in rat models by comparing different materials and study the changes in biomechanical properties over time. METHODS: TERM was constructed by seeding adipose-derived stem cells (ADSCs) on electrospun poly(L-lactide)-trimethylene carbonate-glycolide (PLTG) terpolymers. The TERM, PLTG, porcine small intestine submucosa mesh (SIS), and polypropylene (PP) (n = 6 / group per time point) were implanted in rats for 7, 30, 60, and 90 days. Hematoxylin-eosin and Masson's trichrome staining were used to assess the host response, and mechanical testing was used to evaluate the changes in biomechanical properties. RESULTS: In vivo imaging showed that the ADSCs were confined to the abdominal wall and did not migrate to other organs or tissues. The TERM was encapsulated by a thicker layer of connective tissue and was associated with less reduced inflammatory scores compared with PLTG and PP over time. The vascularization of the TERM was greater than that with PP and PLTG over time (p < 0.05) and was greater than that with SIS on day 90. The ultimate tensile strain and Young's modulus of the PP group showed the greatest increases, and the TERM group followed on day 90. CONCLUSIONS: This TERM achieved better host integration in rat models and better biomechanical properties, and it may be an alternative material for PFD.

Microplastics induce immune suppression via S100A8 downregulation.

Microplastic (MP) pollution has been largely reported in the daily consumption of water and food, however, the toxicities of MPs to human beings remain largely uncovered. We found that MPs in drinking water significantly impaired mouse immune function by reducing spleen weight, CD8+ T cell amount and raising CD4+ to CD8+ T cell ratio. We performed proteomics and phosphoproteomics by LC-MS/MS and found MPs significantly induced 130 and 57 proteins upregulated in proteome and phosphoproteome, and 191 and 37 proteins downregulated in proteome and phosphoproteome, separately. Bioinformatic analysis show that asthma, mineral absorption, and the IL-17 signaling pathway were significantly enriched and may be involved in MP-induced spleen damage and immune suppression. We verified the top 3 differentially expressed proteins and phosphoproteins by western blot, and we further showed that S100A8 was significantly downregulated by MPs via histochemistry staining. Our results revealed that MPs can induce spleen damage and immune suppression by reducing S100A8 expression, suggesting an underestimated influence and mechanism of MPs on the mammalian immune system.

Responses of bacterial communities and antibiotic resistance genes to nano-cellulose addition during pig manure composting.

Treatment with exogenous additives during composting can help to alleviate the accumulation of antibiotic resistance genes (ARGs) caused by the direct application of pig manure to farmland. In addition, nano-cellulose has an excellent capacity for adsorbing pollutants. Thus, the effects of adding 300, 600, and 900 mg/kg nano-cellulose to compost on the bacterial communities, mobile genetic elements (MGEs), and ARGs were determined in this study. After composting, treatment with nano-cellulose significantly reduced the relative abundance of ARGs, which was lowest in the compost product with 600 mg/kg added nano-cellulose. Nano-cellulose inhibited the rebound in ARGs from the cooling period to the maturity period, and weakened the selective pressure of heavy metals on microorganisms by passivating bio-Cu. The results also showed that MGEs explained most of the changes in the abundances of ARGs, and MGEs had direct effects on ARGs. The addition of 600 mg/kg nano-cellulose reduced the abundances of bacterial genera associated with ermQ, tetG, and other genes, and the number of links (16) between ARGs and MGEs was lowest in the treatment with 600 mg/kg added nano-cellulose. Therefore, adding 600 mg/kg nano-cellulose reduced the abundances of ARGs by affecting host bacteria and MGEs. The results obtained in this study demonstrate the positive effect of nano-cellulose on ARG pollution in poultry manure, where adding 600 mg/kg nano-cellulose was most effective at reducing the abundances of ARGs.

Sialic Acid-Functionalized PEG-PLGA Microspheres Loading Mitochondrial-Targeting-Modified Curcumin for Acute Lung Injury Therapy.

Acute lung injury (ALI) is a serious illness without resultful therapeutic methods commonly. Recent studies indicate the importance of oxidative stress in the occurrence and development of ALI, and mitochondria targeted antioxidant has become a difficult and hot topic in the research of ALI. Therefore, a sialic acid (SA)-modified lung-targeted microsphere (MS) for ALI therapy are developed, with triphenylphosphonium cation (TPP)-modified curcumin (Cur-TPP) loaded, which could specifically target the mitochondria, increasing the effect of antioxidant. The results manifest that with the increase of microsphere, lung distribution of microsphere is also increased in murine mice, and after SA modification, the microsphere exhibits the ideal lung-targeted characteristic in ALI model mice, due to SA efficiently targeting to E-selectin expressed on inflammatory tissues. Further investigations indicate that SA/Cur-TPP/MS has better antioxidative capacity, decreases intracellular ROS generation, and increases mitochondrial membrane potential, contributing to a lower apoptosis rate in human umbilical vein endothelial cells (HUVECs) compared to H2O2 group. In vivo efficacy of SA/Cur-TPP/MS demonstrates that the inflammation has been alleviated markedly and the oxidative stress is ameliorated efficiently. Significant histological improvements by SA/Cur-TPP/MS are further proved via HE stains. In conclusion, SA/Cur-TPP/MS might act as a promising drug formulation for ALI therapy.

Synthesis of highly luminescent and biocompatible CdTe/CdS/ZnS quantum dots using microwave irradiation: a comparative study of different ligands.

We compared the effects of several ligands frequently used in aqueous synthesis, including L-cysteine, L-cysteine hydrochloride, N-acetyl-L-cysteine (NAC), glutathione and 3-mercaptopropionic acid, for microwave synthesis of CdTe quantum dots (QDs) in a sealed vessel with varied temperatures and times, and then developed a rapid microwave-assisted protocol for preparing highly luminescent, photostable and biocompatible CdTe/CdS/ZnS core-multishell QDs. The effects of molecular structures of these ligands on QD synthesis under high temperatures were explored. Among these ligands, NAC was found to be the optimal ligand in terms of the optical properties of resultant QDs and reaction conditions. The emission wavelength of NAC-capped CdTe QDs could reach 700 nm in 5 min by controlling the reaction temperature, and the resultant CdTe/CdS/ZnS core-multishell QDs could achieve the highest quantum yields up to 74% with robust photostability. In addition, the effects of temperature, growth time and shell-precursor ratio on shell growth were examined. Finally, cell culturing indicated the low cytotoxicity of CdTe/CdS/ZnS core-multishell QDs as compared to CdTe and CdTe/CdS QDs, suggesting their high potential for applications in biomedical imaging and diagnostics.

[Comparison of the occlusion effect of three kinds of desensitizers on dentinal tubules].

OBJECTIVE: To explore the effects of three dentine desensitizers on the surface morphology of freshly exposed dentin and to evaluate their occlusion effects on dentinal tubules using scanning electron microscope (SEM). METHODS: A total of 16 isolated human premolar samples, which were prepared to expose dentine, were randomly divided into a control group (n=4), a Hybrid Coat group (n=4), a Prime & Bond NT group (n=4), and a anti-sensitivity toothpaste group (n=4). After treatment with dentine desensitizers, one half of the samples in each group were vertically cleaved. Finally, the surfaces and cross sections of the samples were observed by SEM. RESULTS: The exposed tubule was almost occluded in the Hybrid Coat group and the Prime & Bond NT group, while only the majority of tubules could be sealed in the anti-sensitivity toothpaste group. The cross-section images showed that sediments were visible in all groups except the control group. CONCLUSION: Hybrid Coat and Prime & Bond NT are able to effectively seal tubules, while the effect of anti-sensitivity toothpaste is slightly poor.

Armoring a liposome-integrated tissue factor with sacrificial CaCO3 to form potent self-propelled hemostats.

The development of hemostatic materials suitable for diverse emergency scenarios is of paramount significance, and there is growing interest in wound-site delivery of hemostasis-enhancing agents that can leverage the body's inherent mechanisms. Herein we report the design and performance of a biomimetic nanoparticle system enclosing tissue factor (TF), the most potent known blood coagulation trigger, which was reconstituted into liposomes and shielded by the liposome-templated CaCO3 mineralization. The mineral coatings, which mainly comprised water-soluble amorphous and vateritic phases, synergized with the lipidated TF to improve blood coagulation in vitro. These coatings served as sacrificial masks capable of releasing Ca2+ coagulation factors or propelling the TF-liposomes via acid-aided generation of CO2 bubbles while endowing them with high thermostability under dry conditions. In comparison to commercially available hemostatic particles, CaCO3 mineralized TF-liposomes yielded significantly shorter hemostasis times and less blood loss in vivo. When mixed with organic acids, the CO2-generating formulation further improved hemostasis by delivering TF-liposomes deep into actively bleeding wounds with good biocompatibility, as observed in a rat hepatic injury model. Therefore, the designed composite mimicry of coagulatory components exhibited strong hemostatic efficacy, which in combination with the propulsion mechanism would serve as a versatile approach to treating a variety of severe hemorrhages.

Sub-50 nm core-shell nanoparticles with the pH-responsive squeezing release effect for targeting therapy of hepatocellular carcinoma.

The development of drug delivery systems with high drug loading capacity, low leakage at physiological pH, and rapid release at the lesion sites remains an ongoing challenge. In this work, core-shell poly(6-O-methacryloyl-D-galactose)@poly(tert-butyl methacrylate) (PMADGal@PtBMA) nanoparticles (NPs) of sub-50 nm are facilely synthesized by reversible addition-fragmentation chain transfer (RAFT) soap-free emulsion polymerization with the assistance of 12-crown-4. A hydrophilic poly(methacrylic acid) (PMAA) core can then be revealed after deprotection of the tert-butyl groups, which is negatively charged and can adsorb nearly 100% of incubated doxorubicin (DOX) from a solution at pH 7.4. The physical shrinkage of PMAA chains below pH 6.0 endows the core with the squeezing effect, therefore realizing rapid drug release. It is demonstrated that the DOX release rate of PMADGal@PMAA NPs at pH 5 was 4 times that at pH 7.4. Cellular uptake experiments confirm the high targeting ability of the galactose modified PMADGal shell to human hepatocellular carcinoma (HepG2) cells. The fluorescence intensity of DOX in HepG2 cells is 4.86 times that of HeLa cells after 3 h incubation. Moreover, 20% cross-linked NPs show the highest uptake efficiency by HepG2 cells due to their moderate surface charge, size and hardness. In summary, both the core and the shell of PMADGal@PMAA NPs promise the rapid site-specific release of DOX in HepG2 cells. This work provides a facile and an effective strategy to synthesize core-shell NPs for hepatocellular carcinoma targeting therapy.

Enhanced anti-microbial activity and osseointegration of Ta/Cu co-implanted polyetheretherketone.

Polyetheretherketone (PEEK) has been widely applied for orthopedic and oral implants due to its excellent mechanical properties, biocompatibility, and radiolucency. However, its bioinert and the lack of anti-microbial activity limit its application. We modified the PEEK surface with Ta/Cu co-implantation using plasma immersion ion-implantation technology. After implantation of Ta/Cu ions, the morphology and roughness of the PEEK surface were not significantly changed at micron level. We estimated the cytocompatibility, anti-microbial ability, and osteogenic differentiation of rat bone mesenchymal stem cells (BMSCs) of the modified surfaces in vitro. Compared to the untreated surfaces, the Ta ion-treated surface showed improved adhesion, proliferation, ALP activity, ECM mineralization, and osteogenic gene expression of BMSCs. Further, the Cu ion-treated surface showed reduced initial adhesion and proliferation of Escherichia coli and Staphylococcus aureus in vitro and proliferation of Staphylococcus aureus in the mouse subcutaneous implant-associated infection model. According to a rat bone repair model, all Ta ion-implanted groups demonstrated improved new bone formation. In summary, Ta/Cu ion co-impanation improved anti-microbial activity and promoted osseointegration of the PEEK surface.

TPGS-based and S-thanatin functionalized nanorods for overcoming drug resistance in Klebsiella pneumonia.

Tigecycline is regarded as the last line of defense to combat multidrug-resistant Klebsiella pneumoniae. However, increasing utilization has led to rising drug resistance and treatment failure. Here, we design a D-alpha tocopheryl polyethylene glycol succinate-modified and S-thanatin peptide-functionalized nanorods based on calcium phosphate nanoparticles for tigecycline delivery and pneumonia therapy caused by tigecycline-resistant Klebsiella pneumoniae. After incubation with bacteria, the fabricated nanorods can enhance tigecycline accumulation in bacteria via the inhibitory effect on efflux pumps exerted by D-alpha tocopheryl polyethylene glycol succinate and the targeting capacity of S-thanatin to bacteria. The synergistic antibacterial capacity between S-thanatin and tigecycline further enhances the antibacterial activity of nanorods, thus overcoming the tigecycline resistance of Klebsiella pneumoniae. After intravenous injection, nanorods significantly reduces the counts of white blood cells and neutrophils, decreases bacterial colonies, and ameliorates neutrophil infiltration events, thereby largely increasing the survival rate of mice with pneumonia. These findings may provide a therapeutic strategy for infections caused by drug-resistant bacteria.

Excellent Multiphoton Excitation Fluorescence with Large Multiphoton Absorption Cross Sections of Arginine-Modified Gold Nanoclusters for Bioimaging.

Fluorescent gold nanoclusters (Au NCs) with excellent one-photon and multiphoton properties have been demonstrated as promising candidates in many application fields. However, small multiphoton absorption (MPA) cross sections and weak multiphoton excitation (MPE) fluorescence impede their practical applications under near-infrared (NIR) excitation for biological imaging. Here, we report the regulated one-photon and multiphoton properties and mechanisms of arginine-stabilized 6-aza-2-thiothymine Au NCs (Arg/ATT-Au NCs) and the applications for MPE fluorescence imaging. The introduction of arginine into the capping layer of ATT-Au NCs significantly modifies the electronic structure, the absorption cross sections, and the relaxation dynamics of the lowest excited state, drastically reducing the nonradiative relaxation, suppressing the blinking, and greatly enhancing the fluorescence. Besides the improved one-photon properties, Arg/ATT-Au NCs demonstrate remarkable MPE fluorescence with a large MPA cross section. The two-photon (λex = 850 nm), three-photon (λex = 1400 nm), and four-photon (λex = 1700 nm) absorption cross sections have been determined to be 6.1 × 10-47 cm4 s1 photon-1, 1.5 × 10-78 cm6 s2 photon-2, and 5.5 × 10-108 cm8 s3 photon-3, respectively, much higher than those of conventional organic compounds and previously reported Au NCs. Moreover, Arg/ATT-Au NCs have been successfully applied in two-photon and three-photon excitation fluorescence imaging of living cells with NIR excitation. The manifold advantages of small size, high quantum yield, suppressed blinking, good photostability and cytocompatibility, large MPA cross sections, and excellent MPE fluorescence imaging performances make fluorescent Arg/ATT-Au NCs a great candidate of imaging probes with vis-NIR excitation.

Characterization of the effective cellulose degrading strain CTL-6.

An efficient cellulose degrading bacteria exists in the thermophilic wheat straw-degrading community, WDC2. However, this strain cannot be isolated and cultured using conventional separation techniques under strict anaerobic conditions. We successfully isolated a strain of effective cellulose degrading bacteria CTL-6 using a wash, heat shock, and solid-liquid alternating process. Analysis of its properties revealed that, although the community containing the strain CTL-6 grew under aerobic conditions, the purified strain CTL-6 only grew under anaerobic culture conditions. The strain CTL-6 had a striking capability of degrading cellulose (80.9% weight loss after 9 days of culture). The highest efficiency value of the endocellulase (CMCase activity) was 0.404 micromol/(min mL), cellulose degradation efficiency by CTL-6 was remarkably high at 50-65 degrees C with the highest degradation efficiency observed at 60 degrees C. The 16S rRNA gene sequence analysis indicated that the closest relative to strain CTL-6 belonged to the genus Clostridium thermocellum. Strain CTL-6 was capable of utilizing cellulose, cellobiose, and glucose. Strain CTL-6 also grew with Sorbitol as the sole carbon source, whereas C. thermocellum is unable to do so.

Succession of diazotroph community and functional gene response to inoculating swine manure compost with a lignocellulose-degrading consortium.

Diazotroph community contributes to the nitrogen mass and improves the agronomic quality of composting product, but their responses to microbial inoculation during composting are unclear. In this study, the lignocellulose-degrading consortium was inoculated at different levels (0%: CK (control) and 10%: T) to investigate their effects on the variations in the diazotroph community and functional gene during composting. In the later composting phase, the nifH gene copy number was 17.50-25.28% higher in T than CK. The nitrogenase abundance in CK and T were 0.042% and 0.046% in composting product, respectively. Network analysis indicated that inoculation affected the co-occurrence patterns of the diazotroph community and changed the keystone species composition. Partial least-squares path modeling showed that available carbon sources and the succession of the diazotroph community mainly determined the increased abundance of nifH gene. Microbial inoculation stimulated the diazotrophs activities, and was conducive to the nitrogen production in composting product.

Well-water-dispersed N-trimethyl chitosan/Fe3O4 hybrid nanoparticles as peroxidase mimetics for quick and effective elimination of bacteria.

Fe3O4 nanoparticles, used as peroxidase mimetics, exhibit splendid future in the biomedical field. However, the functionalization on Fe3O4 nanoparticles always goes with the loss of superparamagnetism and decrease in peroxidase-activity. Here, we synthesized green polyethylene glycol (PEG)-functionalized magnetic/N-trimethyl chitosan (CS) hybrid nanoparticles (Fe3O4@PAA/TMC/PEG NPs) with improved water dispersibility, superparamagnetism, high saturation magnetization and well peroxidase-like activity. The functionalized coating was divided in two steps, one involved a cross-linked PEG/PAA/CS middle layer to protect the nanocrystal Fe3O4 from oxidization, the other was a hydrophilic PEG/TMC outer layer improving the water dispersion, biocompatibility, as well as supplying positive quaternary ammonium groups for a potential increase of cell binding efficiency. The structure, composition and morphology of Fe3O4@PAA/TMC/PEG NPs were characterized by TEM, FT-IR spectroscopy, DLS, zeta potential measurement, respectively. Thermal performance was characterized by TGA, and the peroxidase-like mimics activity was tested by TMB·2HCl colour development experiments. The magnetic property of the as-prepared hybrid nanoparticles was first confirmed by VSM, and then proved by the bacterial pathogens adsorption, especially at ultralow pathogen concentration. Particularly, with an external magnet, the Fe3O4@PAA/TMC/PEG NPs, combined cationic quaternary ammonium groups and peroxidise-mimetic catalytic activity, were tested for antibacterial effect by plating method.

Study on the osteogenesis of rat mesenchymal stem cells and the long-term antibacterial activity of Staphylococcus epidermidis on the surface of silver-rich TiN/Ag modified titanium alloy.

The main causes of failure of orthopedic implants are infection and poor bone ingrowth. Surface modification of the implants to allow for long-term antibacterial and osteogenic functions is an effective solution to prevent failure of the implants. We developed silver-rich TiN/Ag nano-multilayers on the surface of titanium alloy with different doses of Ag+ . The antibacterial stability and osteogenesis of the silver-rich surface were determined by evaluating the adhesion and proliferation of Staphylococcus epidermidis, and the adhesion, proliferation, alkaline phosphatase activity, extracellular matrix mineralization, and the expression level of genes involved in osteogenic differentiation of rat bone mesenchymal stem cells (BMSCs). The results demonstrated that the antibacterial rates (Ra) of 5 × 1016 -Ag, 1 × 1017 -Ag, 5 × 1017 -Ag, and 1 × 1018 -Ag were respectively 46.21%, 85.66%, 94.99%, 98.48%, and 99.99%. After subcutaneous implantation in rats or immersion in phosphate buffered saline for up to 12 weeks, the silver-rich surface of the titanium alloy showed long-term stable inhibition of Staphylococcus epidermidis. Furthermore, in vitro and in vivo studies indicated that the Ag-implanted titanium did not show apparent cytotoxicity and that lower Ag+ implanted groups (5 × 1016 -Ag, 1 × 1017 -Ag) had better viability and biological safety when compared with higher Ag+ implanted groups. In addition, when compared with the Ti6Al4V-group, all Ag-implanted groups exhibited enhanced osteogenic indicators in rat BMSCs. Regarding osteogenic indicators, the surfaces of the 5 × 1017 -Ag group had better osteogenic effects than those of other groups. Therefore, the proper dose of Ag+ implanted TiN/Ag nano-multilayers may be one of the options for the hard tissue replacement materials with antibacterial activity and osteogenic functions.

Effects of inoculation with lignocellulose-degrading microorganisms on nitrogen conversion and denitrifying bacterial community during aerobic composting.

The present study compared the effects of inoculation (WSD treatment) and non-inoculation (CK treatment) with lignocellulose-degrading microorganisms on nitrogen conversion, nitrogen functional genes, and the denitrifying bacterial community during aerobic composting, and their potential relations to NH3 and N2O emissions were also explored. Results showed that, WSD reduced the NH3 and N2O emissions by 25.9% and 34.98%, respectively, compared with CK. WSD also reduced the abundances of nitrifying (bacteria amoA) and denitrifying (nirS, nirK, and nosZ) genes during composting, which were significantly positively correlated with N2O emissions (P < 0.01). The most important nosZ denitrifying microorganisms belonged to Proteobacteria. Redundancy analysis showed that environmental factors could affect the succession of the denitrifying bacterial community during composting. Based on these results, structural equation modeling demonstrated that the reduction in N2O emissions under WSD was related to the lower accumulation of NO3--N utilized by denitrifying microorganisms during the compost maturation period.

ROS-responsive nano-drug delivery system combining mitochondria-targeting ceria nanoparticles with atorvastatin for acute kidney injury.

Acute kidney injury (AKI) caused by sepsis is a serious disease which mitochondrial oxidative stress and inflammatory play a key role in its pathophysiology. Ceria nanoparticles hold strong and recyclable reactive oxygen species (ROS)-scavenging activity, have been applied to treat ROS-related diseases. However, ceria nanoparticles can't selectively target mitochondria and the ultra-small ceria nanoparticles are easily agglomerated. To overcome these shortcomings and improve therapeutic efficiency, we designed an ROS-responsive nano-drug delivery system combining mitochondria-targeting ceria nanoparticles with atorvastatin for acute kidney injury. Methods: Ceria nanoparticles were modified with triphenylphosphine (TCeria NPs), followed by coating with ROS-responsive organic polymer (mPEG-TK-PLGA) and loaded atorvastatin (Atv/PTP-TCeria NPs). The physicochemical properties, in vitro drug release profiles, mitochondria-targeting ability, in vitro antioxidant, anti-apoptotic activity and in vivo treatment efficacy of Atv/PTP-TCeria NPs were examined. Results: Atv/PTP-TCeria NPs could accumulate in kidneys and hold a great ability to ROS-responsively release drug and TCeria NPs could target mitochondria to eliminate excessive ROS. In vitro study suggested Atv/PTP-TCeria NPs exhibited superior antioxidant and anti-apoptotic activity. In vivo study showed that Atv/PTP-TCeria NPs effectively decreased oxidative stress and inflammatory, could protect the mitochondrial structure, reduced apoptosis of tubular cell and tubular necrosis in the sepsis-induced AKI mice model. Conclusions: This ROS-responsive nano-drug delivery system combining mitochondria-targeting ceria nanoparticles with atorvastatin has favorable potentials in the sepsis-induced AKI therapy.