Direct visualization of pyrene diffusion in polyethylene and polyoxymethylene passive samplers.

While passive sampling of ultra-low aqueous concentrations of hydrophobic organic compounds in environmental aqueous media has emerged as a promising analytical technique, there is a lack of good understanding of the fundamental diffusive processes. In this research, we used a fluorophore, pyrene, as a model compound to track diffusion in polymers through absorption and environmental media exchange processes. We directly tracked the penetration of pyrene into polyethylene (PE) and polyoxymethylene (POM) rods during absorption from water by sectioning the rod after different stages of absorption and observing the fluorescence signal through a microscope. Diffusion profiles of pyrene in polymers were simulated by numerical integration of Fickian diffusion. The results indicated that the uptake process in PE is governed by Fick's law and the absorption and desorption kinetics are similar in this polymer. However, the observed uptake profiles of pyrene in POM were non-Fickian and the release kinetics out of POM was slower compared to uptake into the polymer. We show that slower desorption from POM makes corrections for nonequilibrium using performance reference compounds (PRCs) problematic for deployments in water or sediment where there is significant advection. However, for static sediment deployments, the overall kinetics of exchange is controlled by slow transport through sediment and the hysteretic behavior of POM may not preclude the use of PRCs to interpret equilibrium status.

Strong aggregation-induced electrochemiluminescence of pyrene-coordination metal-organic frameworks coupled with zero-valent iron as novel accelerator for ultrasensitive immunoassay.

Polycyclic aromatic hydrocarbons (PAHs) are excellent alternative luminophores for electrochemiluminescence (ECL) immunoassays. However, they are inevitably limited by the aggregation-caused quenching effect. In this study, aimed at eliminating the aggregation quenching of PAHs, luminescent metal-organic frameworks (MOFs) with 1,3,6,8-tetra(4-carboxybenzene)pyrene (H4TBAPy) as the ligand were exploited as a novel nano-emitter for the construction of ECL immunoassays. The luminophore exhibits efficient aggregation-induced emission enhancement, good acid-base resistance property and unusual ECL reactivity. In addition, the simultaneous use of potassium persulfate and hydrogen peroxide as dual co-reactants resulted in a synergistic enhancement of the cathodic ECL efficiency. The use of magnetic iron-nickel alloys as the multifunctional sensing platform can further enhance the ECL activity, and its enriched zero-valent iron as a co-reactant accelerator effectively drives ECL analytical performance. Profiting from the excellent characteristics, signal-on ECL immunoassays have been constructed. With carcinoembryonic antigen as the model analysis target, a detection limit of 0.63 pg/mL was obtained within the linear range of 1 pg/mL to 50 ng/mL, accompanied by excellent analytical performance. This report opens a new window for the rational design of efficient ECL illuminators, and the proposed ECL immunoassays may find promising applications in the detection of disease markers.

Pyrene Derivative Incorporated Ni MOF as an Enzyme Mimic for Noninvasive Salivary Glucose Detection Toward Diagnosis of Diabetes Mellitus.

Herein, we demonstrate the detection of glucose in a noninvasive and nonenzymatic manner by utilizing an extended gate field-effect transistor (EGFET) based on the organic molecule pyrene phosphonic acid (PyP4OH8) incorporated nickel metal-organic framework (NiOM-MOF). The prepared electrode responds selectively to glucose instead of sucrose, fructose, maltose, ascorbic acid, and uric acid in a 1× phosphate buffer saline solution. Also, utilizing the scanning Kelvin probe system, the sensing electrode's work function (Φ) is measured to validate the glucose-sensing mechanism. The sensitivity, detection range, response time, limit of detection, and limit of quantification of the electrode are determined to be 24.5 µA mM-1 cm-2, 20 µM to 10 mM, less than 5 s, 2.73 µM, and 8.27 µM, respectively. Most interestingly, the developed electrode follows the Michaelis-Menten kinetics, and the calculated rate constant (km) 0.07 mM indicates a higher affinity of NiOM-MOF toward glucose. The real-time analysis has revealed that the prepared electrode is sensitive to detect glucose in real human saliva, and it can be an alternative device for the noninvasive detection of glucose. Overall, the outcomes of the EGFET studies demonstrate that the prepared electrodes are well-suited for expeditious detection of glucose levels in saliva.

Exposure and biomonitoring of PAHs in indoor air at the urban residential area of Iran: Exposure levels and affecting factors.

The concentration of polycyclic aromatic hydrocarbons (PAHs) in the air inside residential houses in Iran along with measuring the amount of 1-OHpyrene metabolite in the urine of the participants in the study was investigated by gas chromatography-mass spectrometry (GC-MS). Demographic characteristics (including age, gender, and body composition), equipment affecting air quality, and wealth index were also investigated. The mean ± standard error (SE) concentration of particulate matter 10 (PM10) and ∑PAHs in the indoor environment was 43.2 ± 1.98 and 1.26 ± 0.15 µg/m3, respectively. The highest concentration of PAHs in the indoor environment in the gaseous and particulate phase related to Naphthalene was 1.1 ± 0.16 µg/m3 and the lowest was 0.01 ± 0. 0.001 µg/m3 Pyrene, while the most frequent compounds in the gas and particle phase were related to low molecular weight hydrocarbons. 30% of the samples in the indoor environment have BaP levels higher than the standards provided by WHO guidelines. 68% of low molecular weight hydrocarbons were in the gas phase and 73 and 75% of medium and high molecular weight hydrocarbons were in the particle phase. There was a significant relationship between the concentration of some PAH compounds with windows, evaporative coolers, printers, and copiers (p < 0.05). The concentration of PAHs in houses with low economic status was higher than in houses with higher economic status. The average concentration of 1-hydroxypyrene metabolite in the urine of people was 7.10 ± 0.76 µg/L, the concentration of this metabolite was higher in men than in women, and there was a direct relationship between the amount of this metabolite in urine and the amount of some hydrocarbon compounds in the air, PM10, visceral fat and body fat. This relationship was significant for age (p = 0.01). The concentration of hydrocarbons in the indoor environment has been above the standard in a significant number of non-smoking indoor environments, and the risk assessment of these compounds can be significant. Also, various factors have influenced the amount of these compounds in the indoor air, and paying attention to them can be effective in reducing these hydrocarbons in the air.

The modulatory effects of large and small extracellular vesicles from normal human urine on calcium oxalate crystallization, growth, aggregation, adhesion on renal cells, and invasion through extracellular matrix: An in vitro study.

Urinary extracellular vesicles (uEVs) play important roles in physiologic condition and various renal/urological disorders. However, their roles in kidney stone disease remain unclear. This study aimed to examine modulatory effects of large and small uEVs derived from normal human urine on calcium oxalate (CaOx) crystals (the main component in kidney stones). After isolation, large uEVs, small uEVs and total urinary proteins (TUPs) with equal (protein equivalent) concentration were added into various crystal assays to compare with the control (without uEVs or TUPs). TUPs strongly inhibited CaOx crystallization, growth, aggregation and crystal-cell adhesion. Large uEVs had lesser degree of inhibition against crystallization, growth and crystal-cell adhesion, and comparable degree of aggregation inhibition compared with TUPs. Small uEVs had comparable inhibitory effects as of TUPs for all these crystal assays. However, TUPs and large uEVs slightly promoted CaOx invasion through extracellular matrix, whereas small uEVs did not affect this. Matching of the proteins reported in six uEVs datasets with those in the kidney stone modulator (StoneMod) database revealed that uEVs contained 18 known CaOx stone modulators (mainly inhibitors). These findings suggest that uEVs derived from normal human urine serve as CaOx stone inhibitors to prevent healthy individuals from kidney stone formation.

Viscosities and Densities of Binary and Ternary Mixtures of Aliphatic and Polyaromatic Hydrocarbons: Pyrene +1-Methylnaphthalene + Dodecane at T = (293.15 to 343.15) K. Experiment and Modeling.

This work presents new experimental viscosity and density data for aromatic and polyaromatic compounds in binary and ternary pyrene, 1-methylnaphthalene, and dodecane mixtures. The lack of experimental viscosity data for these mixtures requires the development of a new database, which is vital for understanding the behavior of mixtures in more complex systems, such as asphaltenes and fuels. The mixtures proposed in this work have been measured over a temperature range of (293.15 to 343.15) K at atmospheric pressure. Several mixture compositions have been studied at these conditions: 1.0, 2.5, 5.0, 7.5, 10.0, 12.5, and 15.0% pyrene mass fraction. The concentration of pyrene correlates with an increase in the viscosity and density values. At the lowest temperature in binary mixtures, the corresponding values reach 4.4217 mPa·s for viscosity and 1.0447 × 103 kg·m-3 for density, respectively. In ternary mixtures, the introduction of dodecane leads to the lowest maximum values of 3.5555 mPa·s for viscosity and 1.0112 × 103 kg·m-3 for density at the same temperature. The experimental data have been employed for the specific modification of viscosity models. These modifications could facilitate the prediction of the viscosity of mixtures that are more complex than those presented in this work. Various viscosity models have been employed, such as Linear, Ratcliff and Khan, modified UNIFAC-Visco, and Krieger-Dougherty. The settings in the models used reliably reproduce the experiment reliably. However, the Ratcliff model agrees excellently with the experiment, having a low standard deviation (2.0%) compared to other models. Furthermore, a model based on the equation of state of Guo is proposed to predict the viscosity values by modifying the specific parameters and adjusting them to the mixtures proposed in this work. The results from this study are compared to previous work, where pyrene, toluene, and heptane mixtures were analyzed. In this case, we find that the decrease of aggregation grade in the present systems is predicted by the model fixed in this work.

Inferior vena cava reconstruction with non-fascial autologous peritoneum: Retrospective study and literature review.

BACKGROUND: Inferior vena cava (IVC) resection is essential for complete (R0) excision of some malignancies. However, the optimal material for IVC reconstruction remains unclear. Our objective is to demonstrate the efficacy, safety, and advantages of using Non-Fascial Autologous Peritoneum (NFAP) for IVC reconstruction. To conduct a literature review of surgical strategies for tumors involving the IVC. METHODS: We reviewed all IVC reconstructions performed at our institution between 2015 and 2023. Preoperative, operative, postoperative, and follow-up data were collected and analyzed. RESULTS: A total of 33 consecutive IVC reconstructions were identified: seven direct sutures, eight venous homografts (VH), and 18 NFAP. With regard to NFAP, eight tubular (mean length, 12.5 cm) and 10 patch (mean length, 7.9 cm) IVC reconstructions were performed. Resection was R0 in 89% of the cases. Two patients had Clavien-Dindo grade I complications, 2 grade II, 2 grade III and 2 grade V complications. The only graft-related complication was a case of early partial thrombosis, which was conservatively treated. At a mean follow-up of 25.9 months, graft patency was 100%. There were seven recurrences and six deaths. Mean overall survival (OS) was 23.4 months and mean disease-free survival (DFS) was 14.4 months. According to our results, no statistically significant differences were found between NFAP and VH. CONCLUSIONS: NFAP is a safe and effective alternative for partial or complete IVC reconstruction and has many advantages over other techniques, including its lack of cost, wide and ready availability, extreme handiness, and versatility. Further comparative studies are required to determine the optimal technique for IVC reconstruction.

Organ-specific biotransformation in salmonids: Insight into intrinsic enzyme activity and biotransformation of three micropollutants.

Aquatic ecosystems continue to be threatened by chemical pollution. To what extent organisms are able to cope with chemical exposure depends on their ability to display mechanisms of defense across different organs. Among these mechanisms, biotransformation processes represent key physiological responses that facilitate detoxification and reduce the bioaccumulation potential of chemicals. Biotransformation does not only depend on the ability of different organs to display biotransformation enzymes but also on the affinity of chemicals towards these enzymes. In the present study, we explored the ability of different organs and of two freshwater fish to support biotransformation processes through the determination of in vitro phase I and II biotransformation enzyme activity, and their role in supporting intrinsic clearance and the formation of biotransformation products. Three environmentally relevant pollutants were evaluated: the polycyclic aromatic hydrocarbon (PAH) pyrene (as recommended by the OECD 319b test guideline), the fungicide azoxystrobin, and the pharmaceutical propranolol. Comparative studies using S9 sub-cellular fractions derived from the liver, intestine, gills, and brain of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) revealed significant phase I and II enzyme activity in all organs. However, organ- and species-specific differences were found. In brown trout, significant extrahepatic biotransformation was observed for pyrene but not for azoxystrobin and propranolol. In rainbow trout, the brain appeared to biotransform azoxystrobin. In this same species, propranolol appeared to be biotransformed by the intestine and gills. Biotransformation products could be detected only from hepatic biotransformation, and their profiles and formation rates displayed species-specific patterns and occurred at different magnitudes. Altogether, our findings further contribute to the current understanding of organ-specific biotransformation capacity, beyond the expression and activity of enzymes, and its dependence on specific enzyme-chemical interactions to support mechanisms of defense against exposure.

Human Airway Organoids and Multimodal Imaging-Based Toxicity Evaluation of 1-Nitropyrene.

Despite significant advances in understanding the general health impacts of air pollution, the toxic effects of air pollution on cells in the human respiratory tract are still elusive. A robust, biologically relevant in vitro model for recapitulating the physiological response of the human airway is needed to obtain a thorough understanding of the molecular mechanisms of air pollutants. In this study, by using 1-nitropyrene (1-NP) as a proof-of-concept, we demonstrate the effectiveness and reliability of evaluating environmental pollutants in physiologically active human airway organoids. Multimodal imaging tools, including live cell imaging, fluorescence microscopy, and MALDI-mass spectrometry imaging (MSI), were implemented to evaluate the cytotoxicity of 1-NP for airway organoids. In addition, lipidomic alterations upon 1-NP treatment were quantitatively analyzed by nontargeted lipidomics. 1-NP exposure was found to be associated with the overproduction of reactive oxygen species (ROS), and dysregulation of lipid pathways, including the SM-Cer conversion, as well as cardiolipin in our organoids. Compared with that of cell lines, a higher tolerance of 1-NP toxicity was observed in the human airway organoids, which might reflect a more physiologically relevant response in the native airway epithelium. Collectively, we have established a novel system for evaluating and investigating molecular mechanisms of environmental pollutants in the human airways via the combinatory use of human airway organoids, multimodal imaging analysis, and MS-based analyses.

Degradable Nanohydroxyapatite-Reinforced Superglue for Rapid Bone Fixation and Promoted Osteogenesis.

Bone glue with robust adhesion is crucial for treating complicated bone fractures, but it remains a formidable challenge to develop a "true" bone glue with high adhesion strength, degradability, bioactivity, and satisfactory operation time in clinical scenarios. Herein, inspired by the hydroxyapatite and collagen matrix composition of natural bone, we constructed a nanohydroxyapatite (nHAP) reinforced osteogenic backbone-degradable superglue (O-BDSG) by in situ radical ring-opening polymerization. nHAP significantly enhances adhesive cohesion by synergistically acting as noncovalent connectors between polymer chains and increasing the molecular weight of the polymer matrix. Moreover, nHAP endows the glue with bioactivity to promote osteogenesis. The as-prepared glue presented a 9.79 MPa flexural adhesion strength for bone, 4.7 times that without nHAP, and significantly surpassed commercial cyanoacrylate (0.64 MPa). O-BDSG exhibited degradability with 51% mass loss after 6 months of implantation. In vivo critical defect and tibia fracture models demonstrated the promoted osteogenesis of the O-BDSG, with a regenerated bone volume of 75% and mechanical function restoration to 94% of the native tibia after 8 weeks. The glue can be flexibly adapted to clinical scenarios with a curing time window of about 3 min. This work shows promising prospects for clinical application in orthopedic surgery and may inspire the design and development of bone adhesives.

Degradation of pyrene by Xanthobacteraceae bacterium strain S3 isolated from the rhizosphere sediment of Vallisneria natans: active conditions, metabolite identification, and proposed pathways.

Polycyclic aromatic hydrocarbons (PAHs) were typical environmental contaminants that accumulated continuously in sediment. Microbial degradation is the main way of PAH degradation in the natural environment. Therefore, expanding the available pool of microbial resources and investigating the molecular degrading mechanisms of PAHs are critical to the efficient control of PAH-polluted sites. Here, a strain (identified as Xanthobacteraceae bacterium) with the ability to degrade pyrene was screened from the rhizosphere sediment of Vallisneria natans. Response surface analysis showed that the strain could degrade pyrene at pH 5-7, NaCl addition 0-1.5%, and temperature 25-40 °C, and the maximum pyrene degradation (~ 95.4%) was obtained under the optimum conditions (pH 7.0, temperature 28.5 °C, and NaCl-free addition) after 72 h. Also, it was observed that the effect of temperature on the degradation ratio was the most significant. Furthermore, eighteen metabolites were identified by mass spectrometry, among which (2Z)-2-hydroxy-3-(4-oxo-4H-phenalen-3-yl) prop-2-enoic acid, 7-(carboxymethyl)-8-formyl-1-naphthyl acetic acid, phthalic acid, naphthalene-1,2-diol, and phenol were the main metabolites. And the degradation pathway of pyrene was proposed, suggesting that pyrene undergoes initial ortho-cleavage under the catalysis of metapyrocatechase to form (2Z)-2-hydroxy-3-(4-oxo-4H-phenalen-3-yl) prop-2-enoic acid. Subsequently, this intermediate was progressively oxidized and degraded to phthalic acid or phenol, which could enter the tricarboxylic acid cycle. Furthermore, the pyrene biodegradation by the strain followed the first-order kinetic model and the degradation rate changed from fast to slow, with the rate remaining mostly slow in the later stages. The slow biodegradation rate was probably caused by a significant amount of phenol accumulation in the initial stage of degradation, which resulted in a decrease in bacterial activity or death.

Remediation of polycyclic aromatic hydrocarbons polluted soil by biochar loaded humic acid activating persulfate: performance, process and mechanisms.

The remediation for polycyclic aromatic hydrocarbons contaminated soil with cost-effective method has received significant public concern, a composite material, therefore, been fabricated by loading humic acid into biochar in this study to activate persulfate for naphthalene, pyrene and benzo(a)pyrene remediation. Experimental results proved the hypothesis that biochar loaded humic acid combined both advantages of individual materials in polycyclic aromatic hydrocarbons adsorption and persulfate activation, achieved synergistic performance in naphthalene, pyrene and benzo(a)pyrene removal from aqueous solution with efficiency reached at 98.2%, 99.3% and 90.1%, respectively. In addition, degradation played a crucial role in polycyclic aromatic hydrocarbons remediation, converting polycyclic aromatic hydrocarbons into less toxic intermediates through radicals of ·SO4-, ·OH, ·O2-, and 1O2 generated from persulfate activation process. Despite pH fluctuation and interfering ions inhibited remediation efficiency in some extent, the excellent performances of composite material in two field soil samples (76.7% and 91.9%) highlighted its potential in large-scale remediation.

Dermal absorption of high molecular weight parent and alkylated polycyclic aromatic hydrocarbons from manufactured gas plant soils using in vitro assessment.

An enhanced in vitro human dermal bioavailability method was developed to measure the release of twenty parent and seven alkylated high molecular weight (HMW) polycyclic aromatic hydrocarbons (PAHs) from contaminated soils collected from five former manufactured Gas Plants (MGP) in England. GC-MS/MS was used to quantify HMW PAHs in soil, Strat-M artificial membrane representing skin, and synthetic receptor solution (RS) representing systemic circulation at 1-h, 10-h, and 24-h timesteps. Fluoranthene and pyrene exhibited the highest fluxes from soils to membrane (ranging from 9.5 - 281 ng/cm2/h) and soil to RS (

Laser-assisted synthesis of nano-hydroxyapatite and functionalization with bone active molecules for bone regeneration.

The main goal of bone tissue engineering research is to replace the allogenic and autologous bone graft substitutes that can promote bone repair. Owing to excellent biocompatibility and osteoconductivity, hydroxyapatite is in extensive research and high demand for both medical and non-medical applications. Although various methods have been developed for the synthesis of hydroxyapatite, in the present study we have shown the use of nanosecond laser energy in the wet precipitation method of nano-hydroxyapatite (nHAP) synthesis without using ammonium solution or any other chemicals for pH maintenance. Here, the present study aimed to fabricate the nanohydroxyapatite using a nanosecond laser. The X-ray diffraction and Fourier transform infrared spectroscopy have confirmed the hydroxyapatite formation under laser irradiation in less time without aging. A transmission electron microscopy confirmed the nano size of synthesized nHAP, which is comparable to conventional nHAP. The length and width of the laser-assisted nHAP were found to be in the range of 50-200 nm and 15-20 nm, respectively, at various laser parameters. The crystallite size obtained by Debye Scherrer formulae was found to be in the range of ∼ 16-36 nm. In addition, laser-assisted nHAP based composite cryogel (nanohydroxyapatite/gelatin/collagen I) was synthesized and impregnated with bioactive molecules (bone morphogenic protein and zoledronic acid) that demonstrated significant osteogenic potential both in vitro in cell experiment and in vivo rat muscle pouch model (abdomen and tibia muscles). Dual-energy X-ray analysis, micro-CT, and histological analysis confirmed ectopic bone regeneration. Micro-CT based histomorphometry showed a higher amount (more than 10-fold) of mineralization for animal groups implanted with composite cryogels loaded with bioactive molecules compared to only composite cryogels groups. Our findings thus demonstrate a controlled and rapid synthetic method for the synthesis of nHAP with various physical, chemical, and biological properties exhibited as comparable to conventionally synthesized nHAP.

Novel insights into the synergetic degradation of pyrene by microbial communities from mangroves in China.

Pyrene is a high molecular weight polycyclic aromatic hydrocarbon (HMW-PAHs). It is a ubiquitous, persistent, and carcinogenic environmental contaminant that has raised concern worldwide. This research explored synergistic bacterial communities for efficient pyrene degradation in seven typical Southern China mangroves. The bacterial communities of seven typical mangroves were enriched by pyrene, and enriched bacterial communities showed an excellent pyrene degradation capacity of > 95% (except for HK mangrove and ZJ mangrove). Devosia, Hyphomicrobium, Flavobacterium, Marinobacter, Algoriphahus, and Youhaiella all have significant positive correlations with pyrene (R>0, p < 0.05) by 16SrRNA gene sequencing and metagenomics analysis, indicated that these genera play a vital role in pyrene metabolism. Meanwhile, the functional genes were involved in pyrene degradation that was enriched in the bacterial communities, including the genes of nagAa, ndoR, pcaG, etc. Furthermore, the analyses of functional genes and binning genomes demonstrated that some bacterial communities as a unique teamwork to cooperatively participate in pyrene degradation. Interestingly, the genes related to biogeochemical cycles were enriched, such as narG , soxA, and cyxJ, suggested that bacterial communities were also helpful in maintaining the stability of the ecological environment. In addition, some novel species with pyrene-degradation potential were identified in the pyrene-degrading bacterial communities, which can enrich the resource pool of pyrene-degrading strains. Overall, this study will help develop further research strategies for pollutant removal.

Disposable paper electrodes for detection of changes in dopamine concentrations in rat brain homogenates.

Dopamine, the main catecholamine neurotransmitter plays an important role in renal, cardiovascular, central nervous systems, and pathophysiological processes. The abnormal dopamine levels can result in neurological disorders such as Parkinson's, Alzheimer's, schizophrenia, acute anxiety, neuroblastoma and also contribute to cognitive dysfunctions. Given the widespread importance of dopamine concentration levels, it is imperative to develop sensors that are able to monitor dopamine. Herein, we have developed pre-anodized disposable paper electrode modified with 1-pyrenebutyric acid, for the selective and sensitive determination of dopamine. The sensor was characterized with Fourier transform infrared spectroscopy, Energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and electrochemical techniques for addressing the robust formation and electrochemical activity. The modified electrode exhibited excellent electrocatalytic activity towards dopamine without the common interference from ascorbic acid. The calibration plot for the dopamine sensor resulted linear range from 0.003 µM to 0.5 µM with a detection limit of 0.11 nM. The sensor's potential utility was tested by monitoring dopamine concentration changes in rat brain homogenates when subjected to neurotoxicity. The developed sensor was validated with gold-standard UV-Vis spectroscopy studies and computational studies were performed to understand the interaction between 1-pyrenebutyric acid and dopamine.

Functional amyloid fibrils of biofilm-forming marine bacterium Pseudomonas aeruginosa PFL-P1 interact spontaneously with pyrene and augment the biodegradation.

Bacteria thrive in biofilms embedding in the three-dimensional extracellular polymeric substances (EPS). Functional Amyloid in Pseudomonas (Fap), a protein in EPS, efficiently sequesters polycyclic aromatic hydrocarbons (PAHs). Present study reports the characterization of Fap fibrils from Pseudomonas aeruginosa PFL-P1 and describes the interaction with pyrene to assess the impact on pyrene degradation. Overexpression of fap in E. coli BL21(DE3) cells significantly enhances biofilm formation (p < 0.0001) and amyloid production (p = 0.0002), particularly with pyrene. Defibrillated Fap analysis reveals FapC monomers and increased fibrillation with pyrene. Circular Dichroism (CD), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD) unveil characteristic amyloid peaks and structural changes in Fap fibrils upon pyrene exposure. 3D-EEM analysis identifies a protein-like fluorophore in Fap fibrils, exhibiting pyrene-induced fluorescence quenching. Binding constants range from 5.23 to 7.78 M-1, with ΔG of -5.10 kJ mol-1 at 298 K, indicating spontaneous and exothermic interaction driven by hydrophobic forces. Exogenous Fap fibrils substantially increased the biofilm growth and pyrene degradation by P. aeruginosa PFL-P1 from 46 % to 64 % within 7 days (p = 0.0236). GC-MS identifies diverse metabolites, implying phthalic acid pathway in pyrene degradation. This study deepens insights into structural dynamics of Fap fibrils when exposed to pyrene, offering potential application in environmental bioremediation.

Experimental determination of the partitioning of representative organic pollutants to the air-water interface.

Using glancing-angle laser-induced fluorescence (GALIF) spectroscopy as a probe, the partitioning of naphthalene, fluoranthene, pyrene, umbelliferone, phenol red, and bisphenol A from bulk solution to the air-water interface was examined in both pure water and aqueous solutions of 6 mM octanol. Previous studies provided similar Langmuir adsorption isotherms for anthracene and imidazole 2-carboxaldehyde. The surface partitioning behaviour of each compound in both environments was well described using a Langmuir adsorption model; partitioning coefficients were derived from the fits to such isotherms. Only the PAH molecules, naphthalene, fluoranthene and pyrene, saw an enhancement in the surface partitioning in octanol solution compared to pure water. The surface partitioning to pure water surfaces could be fairly well described using a one parameter linear free energy relationship based on either solubility or KOW.

ALKBH5 SUMOylation-mediated FBXW7 m6A modification regulates alveolar cells senescence during 1-nitropyrene-induced pulmonary fibrosis.

Our previous study revealed that 1-nitropyrene (1-NP) exposure evoked pulmonary fibrosis in mice. However, the exact mechanism remained elusive. We found that 1-NP induced telomere damage and cellular senescence in mice lungs, and two alveolar epithelial cells lines. 1-NP downregulated telomere repeat binding factor 2 (TRF2), and upregulated FBXW7. Mechanistically, 1-NP-caused TRF2 ubiquitination and proteasomal degradation depended on E3 ubiquitin ligase activity of FBXW7. Moreover, 1-NP upregulated FBXW7 m6A modification via an ALKBH5-YTHDF1-dependent manner. Further analysis suggested 1-NP promoted ALKBH5 SUMOylation and subsequent proteasomal degradation. Additionally, 1-NP evoked mitochondrial reactive oxygen species (mtROS) overproduction. Mito-TEMPO, a mitochondrial-targeted antioxidant, mitigated 1-NP-caused mtROS overproduction, ALKBH5 SUMOylation, FBXW7 m6A modification, TRF2 degradation, cellular senescence, and pulmonary fibrosis. Taken together, mtROS-initiated ALKBH5 SUMOylation and subsequent FBXW7 m6A modification is indispensable for TRF2 degradation and cellular senescence in alveolar epithelial cells during 1-NP-induced pulmonary fibrosis. Our study provides target intervention measures towards 1-NP-evoked pulmonary fibrosis.

A novel mycelial pellet applied to remove polycyclic aromatic hydrocarbons: High adsorption performance & its mechanisms.

Mycelial pellets formed by Penicillium thomii ZJJ were applied as efficient biosorbents for the removal of polycyclic aromatic hydrocarbons (PAHs), which are a type of ubiquitous harmful hydrophobic pollutants. The live mycelial pellets were able to remove 93.48 % of pyrene at a concentration of 100 mg/L within 48 h, demonstrating a maximum adsorption capacity of 285.63 mg/g. Meanwhile, the heat-killed one also achieved a removal rate of 65.01 %. Among the six typical PAHs (pyrene, phenanthrene, fluorene, anthracene, fluoranthene, benzo[a]pyrene), the mycelial pellets preferentially adsorbed the high molecular weight PAHs, which also have higher toxicity, resulting in higher removal efficiency. The experimental results showed that the biosorption of mycelial pellets was mainly a spontaneous physical adsorption process that occurred as a monolayer on a homogeneous surface, with mass transfer being the key rate-limiting step. The main adsorption sites on the surface of mycelia were carboxyl and N-containing groups. Extracellular polymeric substances (EPS) produced by mycelial pellets could enhance adsorption, and its coupling with dead mycelia could achieve basically the same removal effect to that of living one. It can be concluded that biosorption by mycelial pellets occurred due to the influence of electrostatic and hydrophobic interactions, consisting of five steps. Furthermore, the potential applicability of mycelial pellets has been investigated considering diverse factors. The mycelia showed high environmental tolerance, which could effectively remove pyrene across a wide range of pH and salt concentration. And pellets diameters and humic acid concentration had a significant effect on microbial adsorption effect. Based on a cost-effectiveness analysis, mycelium pellets were found to be a low-cost adsorbent. The research outcomes facilitate a thorough comprehension of the adsorption process of pyrene by mycelial pellets and their relevant applications, proposing a cost-effective method without potential environmental issues (heat-killed mycelial pellets plus EPS) to removal PAHs.