Reduction characteristic of chlorobenzene by a newly isolated Paenarthrobacter ureafaciens LY from a pharmaceutical wastewater treatment plant.

A highly efficient chlorobenzene-degrading strain was isolated from the sludge of a sewage treatment plant associated with a pharmaceutical company. The strain exhibited a similarity of over 99.9% with multiple strains of Paenarthrobacter ureafaciens. Therefore, the strain was suggested to be P. ureafaciens LY. This novel strain exhibited a broad spectrum of pollutant degradation capabilities, effectively degrading chlorobenzene and other organic pollutants, such as 1, 2, 4-trichlorobenzene, phenol, and xylene. Moreover, P. ureafaciens LY co-metabolized mixtures of chlorobenzene with 1, 2, 4-trichlorobenzene or phenol. Evaluation of its degradation efficiency showed that it achieved an impressive degradation rate of 94.78% for chlorobenzene within 8 h. The Haldane-Andrews model was used to describe the growth of P. ureafaciens LY under specific pollutants and its concentrations, revealing a maximum specific growth rate (µmax ) of 0.33 h-1 . The isolation and characterization of P. ureafaciens LY, along with its ability to degrade chlorobenzene, provides valuable insights for the development of efficient and eco-friendly approaches to mitigate chlorobenzene contamination. Additionally, investigation of the degradation performance of the strain in the presence of other pollutants offers important information for understanding the complexities of co-metabolism in mixed-pollutant environments.

Evidence for the latest fossil Pongo in southern China.

Pongo fossils with precise absolute age brackets are rare, limiting our understanding of their taxonomy and spatiotemporal distribution in southern China during the Late Pleistocene. Twenty-four isolated teeth of fossil orangutans were recently discovered during excavations at Yicun Cave in Guangxi Zhuang Autonomous Region, southern China. Here, we dated the fossil-bearing layer using Uranium-series dating of the associated flowstone and soda straw stalactites. Our results date the Yicun orangutan fossils to between 66 ± 0.32 ka and 57 ± 0.26 ka; thus, these fossils currently represent the last appearance datum of Pongo in southern China. We further conducted a detailed morphological comparison of the Yicun fossil teeth with large samples of fossil (n = 2454) and extant (n = 441) orangutans from mainland and island Southeast Asia to determine their taxonomic position. Compared to other fossil and extant orangutan samples, the Yicun Pongo assemblage has larger teeth and displays greater variation in occlusal structure. Based on the high frequency of cingular remnants and light to moderate enamel wrinkling of the molars, we assigned the Yicun fossils to Pongo weidenreichi, a species that was widespread in southern China throughout the Pleistocene. Lastly, we used published stable carbon isotope data of Early to Late Pleistocene mammalian fossil teeth from mainland Southeast Asia to reconstruct changes in the paleoenvironment and to interpret dental size variation of Pongo assemblages in a broader temporal and environmental context. The carbon isotope data show that dental size reduction in Pongo is associated with environmental changes. These morphological changes in Pongo appear to coincide with the expansion of savannah biomes and the contraction of forest habitats from the Middle Pleistocene onward. The variation in dental size of forest-dwelling Pongo in mainland Southeast Asia may have resulted from habitat differentiation during the Pleistocene.

Symptomatic intracranial hemorrhage in patients with admission hyperglycemia and diabetes after mechanical thrombectomy: A systematic review and meta-analysis.

OBJECTIVES: Symptomatic intracranial hemorrhage (sICH) is a severe complication of revascularization therapy. We aimed to investigate the association of admission hyperglycemia and sICH after mechanical thrombectomy in patients with acute ischemic stroke. METHODS: We systematically searched PubMed, EMBASE and Cochrane Library to identify studies that reported incidence of sICH in patients with admission hyperglycemia and normoglycemia, or with and without a history of diabetes, or glucose level in patients with sICH and non-sICH from inception to December 10, 2019. The estimate effects were pooled by random-effects model. RESULTS: Twelve eligible studies were included with 4892 patients enrolled. The risk of sICH was significantly higher in admission hyperglycemia patients than that in normoglycemia (OR 2.93, 95% CI 1.34-6.42, p = 0.007; adjusted OR1.95, 95% CI 1.22-3.13; p = 0.006). The admission glucose level was significantly higher in sICH patients than that in non-sICH with a mean difference of 37.49 (95% CI 3.03-71.94, p = 0.03). The risk of sICH increased with elevating glucose level (adjusted OR 1.06, 95% CI 1.01-1.11; p = 0.02). The risk of sICH was not significantly increased in patients with a history of diabetes than that of those without (OR 1.74, 95% CI 1.00-3.03, p = 0.05; adjusted OR 2.26, 95% CI 0.97-5.28; p = 0.06). CONCLUSIONS: In patients of acute ischemic stroke treated with mechanical thrombectomy, the risk of sICH was associated with admission hyperglycemia but possibly not with a history of diabetes.

Performance on adsorption of toluene by ionic liquid-modified AC in high-humidity exhaust gas.

Volatile organic compounds (VOCs) frequently pose a threat to the biosphere, impacting ecosystems, flora, fauna, and the surrounding environment. Industrial emissions of VOCs often include the presence of water vapor, which, in turn, diminishes the adsorption capacity and efficacy of adsorbents. This occurs due to the competitive adsorption of water vapor, which competes with target pollutants for adsorption sites on the adsorbent material. In this study, hydrophobic activated carbons (BMIMPF6-AC (L), BMIMPF6-AC (g), and BMIMPF6-AC-H) were successfully prepared using 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6) to adsorb toluene under humidity environment. The adsorption performance and mechanism of the resulting ionic liquid-modified activated carbon for toluene in a high-humidity environment were evaluated to explore the potential application of ionic liquids as hydrophobic modifiers. The results indicated that BMIMPF6-AC-H exhibited superior hydrophobicity. The toluene adsorption capacity of BMIMPF6-AC-H was 1.53 times higher than that of original activated carbon, while the adsorption capacity for water vapor was only 37.30% of it at 27 °C and 77% RH. The Y-N model well-fitted the dynamic adsorption experiments. To elucidate the microscopic mechanism of hydrophobic modification, the Independent Gradient Model (IGM) method was employed to characterize the intermolecular interactions between BMIMPF6 and toluene. Overall, this study introduces a new modifier for hydrophobic modification of activated carbon, which could enhance the efficiency of activated carbon in treating industrial VOCs.

Ultrasound-assisted H2O2 directional-modification of powdered activated carbon for the enhanced adsorption of secondary effluent organic matter from printing and dyeing processes.

The physicochemical properties of powdered activated carbon (PAC) are important factors affecting its adsorption performance, which is also related to the characteristics of target organic pollutants. In this study, the key indicators affecting the adsorption performance of PAC were identified, and the physicochemical properties of PACs were modified by hydrogen peroxide and/or ultrasound in a targeted manner to improve the adsorption performance. The results indicated the adsorption properties of printing and dyeing secondary effluent organic matter (EfOM) in terms of CODcr and UV absorbance at 254 nm (UV254) positively correlated with mesoporous volume, average pore size and acid group content of PAC. After modification, the mesoporous volume and average pore size of PAC increased, and the number of acidic groups increased, thus enhancing the adsorption efficiency. EfOM removal characteristics showed that PAC preferentially adsorbed unsaturated bonds or aromatic compounds, tryptophan-like proteins, soluble microbial metabolites and low molecular weight fractions below 1 kDa. In addition, the relative contents of specific surface area, pore volume and oxygen-containing functional groups (O-CO, C-OH, CO/O-C-O) of PAC decreased after adsorption, indicating that EfOM adsorption was a physical and chemical process, including pore filling, hydrophobic interaction and chemical bond force interaction. In general, PACs with larger mesoporous volume, average pore size and abundant acid groups possessed good adsorption performance towards EfOM.

Photocatalytic inactivation of influenza virus by titanium dioxide thin film.

Titanium dioxide (TiO(2)) under ultraviolet (UV) light produces a strong oxidative effect and may therefore be used as a photocatalytic disinfectant. Although many studies on the photocatalytic inactivation of bacteria have been reported, few studies have addressed virus inactivation. In the present study, we demonstrated the inactivation of influenza virus through TiO(2) photocatalysis using TiO(2) nanoparticles immobilized on a glass plate. The influences of the UV intensity, UV irradiation time and bovine serum albumin (BSA) concentration in the viral suspensions on the inactivation kinetics were investigated. Additionally, we also determined whether the International Organization for Standardization (ISO) methodology for the evaluation of antibacterial activity of TiO(2) photocatalysis could be applied to the evaluation of antiviral activity. The viral titers were dramatically reduced by the photocatalytic reaction. Even with a low intensity of UV-A (0.01 mW cm(-2)), a viral reduction of approximately 4-log(10) was observed within a short irradiation time. The viral inactivation kinetics were associated with the exposure time, the UV intensity and the BSA concentration in virus suspensions. These results show that TiO(2) photocatalysis could be used to inactivate the influenza virus. Furthermore, a minor modification of the ISO test method for anti-bacterial effects of TiO(2) photocatalysis could be useful for the evaluation of antiviral activity.

The First Cbk-Like Phage Infecting Erythrobacter, Representing a Novel Siphoviral Genus.

Erythrobacter is an important and widespread bacterial genus in the ocean. However, our knowledge about their phages is still rare. Here, a novel lytic phage vB_EliS-L02, infecting Erythrobacter litoralis DSM 8509, was isolated and purified from Sanggou Bay seawater, China. Morphological observation revealed that the phage belonged to Cbk-like siphovirus, with a long prolate head and a long tail. The host range test showed that phage vB_EliS-L02 could only infect a few strains of Erythrobacter, demonstrating its potential narrow-host range. The genome size of vB_EliS-L02 was 150,063 bp with a G+C content of 59.43%, encoding 231 putative open reading frames (ORFs), but only 47 were predicted to be functional domains. Fourteen auxiliary metabolic genes were identified, including phoH that may confer vB_EliS-L02 the advantage of regulating phosphate uptake and metabolism under a phosphate-limiting condition. Genomic and phylogenetic analyses indicated that vB_EliS-L02 was most closely related to the genus Lacusarxvirus with low similarity (shared genes < 30%, and average nucleotide sequence identity < 70%), distantly from other reported phages, and could be grouped into a novel viral genus cluster, in this study as Eliscbkvirus. Meanwhile, the genus Eliscbkvirus and Lacusarxvirus stand out from other siphoviral genera and could represent a novel subfamily within Siphoviridae, named Dolichocephalovirinae-II. Being a representative of an understudied viral group with manifold adaptations to the host, phage vB_EliS-L02 could improve our understanding of the virus-host interactions and provide reference information for viral metagenomic analysis in the ocean.

Isolation and Characterization of a Novel Vibrio natriegens­Infecting Phage and Its Potential Therapeutic Application in Abalone Aquaculture

Phage-based pathogen control (i.e., phage therapy) has received increasing scientific attention to reduce and prevent the emergence, transmission, and detrimental effects of antibiotic resistance. In the current study, multidrug-resistant Vibrio natriegens strain AbY-1805 was isolated and tentatively identified as a pathogen causing the death of juvenile Pacific abalones (Haliotis discus hannai Ino). In order to apply phage therapy, instead of antibiotics, to treat and control V. natriegens infections in marine aquaculture environments, a lytic phage, vB_VnaS-L3, was isolated. It could effectively infect V. natriegens AbY-1805 with a short latent period (40 min) and high burst size (~890 PFU/cell). Treatment with vB_VnaS-L3 significantly reduced the mortality of juvenile abalones and maintained abalone feeding capacity over a 40-day V. natriegens challenge experiment. Comparative genomic and phylogenetic analyses suggested that vB_VnaS-L3 was a novel marine Siphoviridae-family phage. Furthermore, vB_VnaS-L3 had a narrow host range, possibly specific to the pathogenic V. natriegens strains. It also exhibited viability at a wide range of pH, temperature, and salinity. The short latent period, large burst size, high host specificity, and broad environmental adaptation suggest that phage vB_VnaS-L3 could potentially be developed as an alternative antimicrobial for the control and prevention of marine animal infections caused by pathogenic V. natriegens.

Photocatalytic inactivation of bacteriophages by TiO2-coated glass plates under low-intensity, long-wavelength UV irradiation.

The International Organization for Standardization (ISO) was used to evaluate antibacterial activity by titanium dioxide (TiO(2)) photocatalysis since 2006. We evaluated photocatalytic inactivation of Qß and T4 bacteriophages induced by low-intensity, long-wavelength ultraviolet A (UVA; 0.1 mW cm(-2) and 0.001 mW cm(-2)) irradiation on a TiO(2)-coated glass plate using the ISO methodology. The results indicated that both bacteriophages were inactivated at 0.001 mW cm(-2) UVA. The intensity of UV light, including long-wavelength light (UVA), is very low in an actual indoor environment. Thus, TiO(2) photocatalysis can be beneficial for inactivating viruses in an indoor environment. Experiments using qPCR and bovine serum albumin degradation assume that viral inactivation is caused by outer viral protein disorder and not by viral RNA reduction by reactive oxygen species produced during TiO(2) photocatalysis. Furthermore, we showed that the ISO methodology for standard testing of antibacterial activity by TiO(2) photocatalysis can be applied to assess antiviral activity.

Electrochemical inactivation kinetics of boron-doped diamond electrode on waterborne pathogens.

A boron-doped diamond (BDD) electrode was constructed as a water disinfector for the inactivation of water borne pathogens. The bactericidal effect of the disinfector was evaluated on artificially contaminated waters containing, respectively, Escherichia coli, Pseudomonas aeruginosa and Legionella pneumophila at high density. By treating the bacterial suspensions with 4 V of constant voltage between the BDD and the counter-electrode for 50 min, the population of E. coli and P. aeruginosa decreased from (10E + 7-8 colony-forming unit mL(-1)) to below the detection limits of the colony-formation method. Meanwhile, L. pneumophila were reduced to virtually zero when analyzed by fluorescence-based staining. The influences of production parameters (voltage, NaCl concentration and flow rate) on the disinfection kinetics of the BDD disinfector were examined with respect to operational conditions. Voltage was the most significant factor for adjusting the extent of electrolysis, followed by NaCl concentration and flow rate, to influence the disinfection efficiency. The disinfection of natural river water samples containing numerous microbes was performed for a practicability investigation of the BDD electrode. Approximately 99.99% bactericidal efficiency was confirmed by viability detection for E. coli and common germs in treated water. The results showed that the BDD electrode is a promising tool for various wastewater disinfections to combat waterborne diseases.

Construction and Analysis of Food-Grade Lactobacillus kefiranofaciens ß-Galactosidase Overexpression System.

Lactobacillus kefiranofaciens contains two types of ß-galactosidase, LacLM and LacZ, belonging to different glycoside hydrolase families. The difference in function between them has been unclear so far for practical application. In this study, LacLM and LacZ from L. kefiranofaciens ATCC51647 were cloned into constitutive lactobacillal expression vector pMG36e, respectively. Furtherly, pMG36n-lacs was constructed from pMG36e-lacs by replacing erythromycin with nisin as selective marker for food-grade expressing systems in Lactobacillus plantarum WCFS1, designated recombinant LacLM and LacZ respectively. The results from hydrolysis of o-nitrophenyl-ß-galactopyranoside (ONPG) showed that the ß-galactosidases activity of the recombinant LacLM and LacZ was 1460% and 670% higher than that of the original L. kefiranofaciens. Moreover, the lactose hydrolytic activity of recombinant LacLM was higher than that of LacZ in milk. Nevertheless, compare to LacZ, in 25% lactose solution the galacto-oligosaccharides (GOS) production of recombinant LacLM was lower. Therefore, two ß-galactopyranosides could play different roles in carbohydrate metabolism of L. kefiranofaciens. In addition, the maximal growth rate of two recombinant strains were evaluated with different temperature level and nisin concentration in fermentation assay for practical purpose. The results displayed that 37°C and 20-40 U/ml nisin were the optimal fermentation conditions for the growth of recombinant ß-galactosidase strains. Altogether the food-grade Expression system of recombinant ß-galactosidase was feasible for applications in the food and dairy industry.

Charging System Optimization of Triboelectric Nanogenerator for Water Wave Energy Harvesting and Storage.

Ocean waves are one of the most promising renewable energy sources for large-scope applications due to the abundant water resources on the earth. Triboelectric nanogenerator (TENG) technology could provide a new strategy for water wave energy harvesting. In this work, we investigated the charging characteristics of utilizing a wavy-structured TENG to charge a capacitor under direct water wave impact and under enclosed ball collision, by combination of theoretical calculations and experimental studies. The analytical equations of the charging characteristics were theoretically derived for the two cases, and they were calculated for various load capacitances, cycle numbers, and structural parameters such as compression deformation depth and ball size or mass. Under the direct water wave impact, the stored energy and maximum energy storage efficiency were found to be controlled by deformation depth, while the stored energy and maximum efficiency can be optimized by the ball size under the enclosed ball collision. Finally, the theoretical results were well verified by the experimental tests. The present work could provide strategies for improving the charging performance of TENGs toward effective water wave energy harvesting and storage.

Photocatalytic activity of Cu2+/TiO2-coated cordierite foam inactivates bacteriophages and Legionella pneumophila.

We investigated the antiviral activity of TiO2-coated cordierite foam used in air cleaners, as well as the evaluation methodology. Furthermore, we developed Cu2+/TiO2-coated cordierite foam and investigated the reduction in viral infection ratio. The method for evaluation of antibacterial activity of TiO2-coated cordierite foam could also be applied to evaluation of antiviral activity. We showed that Cu2+/TiO2-coated cordierite foam reduced the viral infection ratio to a greater extent than TiO2-coated cordierite foam. Our findings suggest that the infection risk by polluted air could be decreased using Cu2+/TiO2-coated cordierite foam in air cleaners.

Antibacterial performance of a novel photocatalytic-coated cordierite foam for use in air cleaners.

A novel titanium dioxide-coated cordierite foam (TiO2/cordierite foam) was developed for use in air cleaners. By a simple impregnation procedure, TiO2 nanoparticles were immobilized firmly onto the surface of a cordierite foam substrate through high-temperature (500 °C) calcination. The strong bactericidal performance of the fabricated foam was evaluated by a newly developed test method for complex three-dimensional through-pore structures. This method could trace 5-6 log units of decrease in bacterial cell numbers in an air environment, thus meeting the criteria of both the JIS and ISO standard test methods. With 0.25 mW cm-2 of UV-A irradiation for 24 h, the bactericidal rate of the TiO2/cordierite foam exceeded 99.9% for five types of airborne or droplet-based infectious pathogens: Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Legionella pneumophila (L. pneumophila), Klebsiella pneumoniae (K. pneumoniae), and methicillin-resistant Staphylococcus aureus (MRSA). The results of repeat testing, where the same sample was used three times, revealed that the bactericidal rate for E. coli was maintained at 99.9% in the second and third use, indicating that the TiO2/cordierite foam possesses a long-term bactericidal action. The TiO2/cordierite foam also exhibited a high photocatalytic degradation capability on gaseous acetaldehyde, which is associated with sick building syndrome, and volatile organic compounds to generate CO2 and H2O. The results demonstrated that TiO2-coated cordierite foam has great potential for use in air-cleaning filters with not only high bactericidal performance to remove pathogens in the air and in droplets, but also strong decontaminating and deodorizing functionality.

Development of solar-driven electrochemical and photocatalytic water treatment system using a boron-doped diamond electrode and TiO2 photocatalyst.

A high-performance, environmentally friendly water treatment system was developed. The system consists mainly of an electrochemical and a photocatalytic oxidation unit, with a boron-doped diamond (BDD) electrode and TiO(2) photocatalyst, respectively. All electric power for the mechanical systems and the electrolysis was able to be provided by photovoltaic cells. Thus, this system is totally driven by solar energy. The treatment ability of the electrolysis and photocatalysis units was investigated by phenol degradation kinetics. An observed rate constant of 5.1 x 10(-3)dm(3)cm(-2)h(-1) was calculated by pseudo-first-order kinetic analysis for the electrolysis, and a Langmuir-Hinshelwood rate constant of 5.6 microM(-1)min(-1) was calculated by kinetic analysis of the photocatalysis. According to previous reports, these values are sufficient for the mineralization of phenol. In a treatment test of river water samples, large amounts of chemical and biological contaminants were totally wet-incinerated by the system. This system could provide 12L/day of drinking water from the Tama River using only solar energy. Therefore, this system may be useful for supplying drinking water during a disaster.

Self-sterilization using silicone catheters coated with Ag and TiO2 nanocomposite thin film.

Ag/titanium dioxide (TiO(2))-coated silicon catheters were easily fabricated with Ag nanoparticles deposition on both the inside wall and the outside wall of TiO(2)-coated catheters by TiO(2) photocatalysis. This is an application of the silicon catheters coated with TiO(2), which possess a self-sterilizing and self-cleaning property combining with UV light illumination (Ohko et al., J Biomed Mater Res: Appl Biomater 2001;58:97). Ag/TiO(2)-coated silicon catheters exhibited a strong bactericidal effect even in the dark. When the 2-5 x 10(5) of colony-forming units of Escherichia coli, Pseudomonas aeruginosa, or Staphylococcus aureus were respectively applied to the surface of the Ag/TiO(2) catheters, which were loaded with approximately 15 nmol cm(-2) of Ag, 99% effective sterilization occurred in a very short time: 20 min for E. coli, 60 min for P. aeruginosa, and 90 min for S. aureus. Additionally, the Ag/TiO(2)-coated catheters possessed a strong self-cleaning property. Using UV illumination, the photocatalytic decomposition rate of methylene blue dye representing the self-cleaning capability, on an Ag/TiO(2) catheter which was loaded with 2 nmol cm(-2) of Ag, was approximately 1.2 times higher (at maximum) than that on TiO(2) coating alone. Furthermore, the Ag nanoparticles can be pre-eminently and uniformly deposited onto the TiO(2) coating, and the amount of Ag was easily controllable from a few nanomoles per square centimeter to approximately 70 nmol cm(-2) by changing the UV illumination time for TiO(2) photocatalysis. This type of catheter shows a great promise in lowering the incidence of catheter-related bacterial infections.

Self-sterilizing catheters with titanium dioxide photocatalyst thin films for clean intermittent catheterization: basis and study of clinical use.

OBJECTIVE: Clean intermittent catheterization (CIC) requires a large number of disposable catheters or a large amount of water and disinfectant. We made titanium dioxide (TiO(2))-coated catheters for CIC using technology we have developed previously, and examined the photocatalytic antibacterial effect of this catheter using only light energy and the safety of this type of catheter for practical clinical use. METHODS: TiO(2)-coated catheters were filled with bacterial cell suspensions and illuminated with a 15-W black-light lamp for testing antibacterial potency. Next, we soaked control toxic materials (zinc diethyldithiocarbamate) and the tips of TiO(2)-coated catheters in M05 medium, and evaluated cell toxicity from the numbers of V79 colonies in these dilutions. Then, bodyweight curves and histological tissue changes were observed over a period of time in mouse-transplanted TiO(2)-coated catheters and control catheters. Finally, we investigated the use of these TiO(2)-coated catheters in 18 patients by questionnaire and bacterial culture of TiO(2)-coated catheters and control catheters. RESULTS: The survival rate of Escherichia coli in the liquid inside the TiO(2) catheter decreased to a negligible level within 60 min under ultraviolet (UV)-A illumination. The survival rate of Staphylococcus aureus, Pseudomonas aeruginosa and Serratia marcescens also decreased to a negligible level within 60 min. V79 cells showed no cytotoxicity of this catheter, and there was no difference in bodyweight or foreign body reaction between mouse-transplanted TiO(2)-coated catheters and control catheters. In a preliminary clinical analysis of 18 patients who voluntarily used this catheter, the rate of positive bacterial culture of the tips of TiO(2)-coated catheters was 20% versus 60% for conventional catheters after 4 weeks of use. CONCLUSION: TiO(2)-coated silicone catheters were easily sterilized under certain light sources and were shown to be safe in an experiment using cultured cells and in animal experiments. Sterilizing catheters with TiO(2) photocatalyst thin films are expected to be used clinically for clean intermittent catheterization after proper modification based on this study.