Cyclometalated iridium(III) tetrazine complexes for mitochondria-targeted two-photon photodynamic therapy.

The fast-moving field of photodynamic therapy (PDT) has provided fresh opportunities to expand the potential of metallodrugs to combat cancers in a light-controlled manner. As such, in the present study, a series of cyclometalated Ir(III) complexes modified with a tetrazine functional group (namely, Ir-ppy-Tz, Ir-pbt-Tz, and Ir-dfppy-Tz) are developed as potential two-photon photodynamic anticancer agents. These complexes target mitochondria but exhibit low toxicity towards HLF primary lung fibroblast normal cells in the dark. When receiving a low-dose one- or two-photon PDT, they become highly potent towards A549 lung cancer cells (with IC50 values ranging from 24.0 nM to 96.0 nM) through the generation of reactive oxygen species (ROS) to induce mitochondrial damage and subsequent apoptosis. Our results indicated that the incorporation of tetrazine with cyclometalated Ir(III) matrices would increase the singlet oxygen (1O2) quantum yield (ΦΔ) and, meanwhile, enable a type I PDT mechanism. Ir-pbt-Tz, with the largest two-photon absorption (TPA) cross-section (σ2 = 102 GM), shows great promise in serving as a two-photon PDT agent for phototherapy.

Formation of nitrogen-containing gas phase products from the heterogeneous (photo)reaction of NO2 with gallic acid.

Heterogeneous reaction of gas phase NO2 with atmospheric humic-like substances (HULIS) is potentially an important source of volatile organic compounds (VOCs) including nitrogen (N)-containing compounds, a class of brown carbon of emerging importance. However, the role of ubiquitous water-soluble aerosol components in this multiphase chemistry, namely nitrate and iron ions, remains largely unexplored. Here, we used secondary electrospray ionization ultrahigh-resolution mass spectrometry for real-time measurements of VOCs formed during the heterogeneous reaction of gas phase NO2 with a solution containing gallic acid (GA) as a proxy of HULIS at pH 5 relevant for moderately acidic aerosol particles. Results showed that the number of detected N-containing organic compounds largely increased from 4 during the NO2 reaction with GA in the absence of nitrate and iron ions to 55 in the presence of nitrate and iron ions. The N-containing compounds have reduced nitrogen functional groups, namely amines, imines and imides. These results suggest that the number of N-containing compounds is significantly higher in deliquescent aerosol particles due to the influence of relatively higher ionic strength from nitrate ions and complexation/redox reactivity of iron cations compared to that in the dilute aqueous phase representative of cloud, fog, and rain water.

Resolving the Formation Mechanism of HONO via Ammonia-Promoted Photosensitized Conversion of Monomeric NO2 on Urban Glass Surfaces.

Understanding the formation processes of nitrous acid (HONO) is crucial due to its role as a primary source of hydroxyl radicals (OH) in the urban atmosphere and its involvement in haze events. In this study, we propose a new pathway for HONO formation via the UVA-light-promoted photosensitized conversion of nitrogen dioxide (NO2) in the presence of ammonia (NH3) and polycyclic aromatic hydrocarbons (PAHs, common compounds in urban grime). This new mechanism differs from the traditional mechanism, as it does not require the formation of the NO2 dimer. Instead, the enhanced electronic interaction between the UVA-light excited triplet state of PAHs and NO2-H2O/NO2-NH3-H2O significantly reduces the energy barrier and facilitates the exothermic formation of HONO from monomeric NO2. Furthermore, the performed experiments confirmed our theoretical findings and revealed that the synergistic effect from light-excited PAHs and NH3 boosts the HONO formation with determined HONO fluxes of 3.6 × 1010 molecules cm-2 s-1 at 60% relative humidity (RH) higher than any previously reported HONO fluxes. Intriguingly, light-induced NO2 to HONO conversion yield on authentic urban grime in presence of NH3 is unprecedented 130% at 60% RH due to the role of NH3 acting as a hydrogen carrier, facilitating the transfer of hydrogen from H2O to NO2. These results show that NH3-assisted UVA-light-induced NO2 to HONO conversion on urban surfaces can be a dominant source of HONO in the metropolitan area.

Comparative Study of α- and ß-MnO2 on Methyl Mercaptan Decomposition: The Role of Oxygen Vacancies.

As a representative sulfur-containing volatile organic compounds (S-VOCs), CH3SH has attracted widespread attention due to its adverse environmental and health risks. The performance of Mn-based catalysts and the effect of their crystal structure on the CH3SH catalytic reaction have yet to be systematically investigated. In this paper, two different crystalline phases of tunneled MnO2 (α-MnO2 and ß-MnO2) with the similar nanorod morphology were used to remove CH3SH, and their physicochemical properties were comprehensively studied using high-resolution transmission electron microscope (HRTEM) and electron paramagnetic resonance (EPR), H2-TPR, O2-TPD, Raman, and X-ray photoelectron spectroscopy (XPS) analysis. For the first time, we report that the specific reaction rate for α-MnO2 (0.029 mol g-1 h-1) was approximately 4.1 times higher than that of ß-MnO2 (0.007 mol g-1 h-1). The as-synthesized α-MnO2 exhibited higher CH3SH catalytic activity towards CH3SH than that of ß-MnO2, which can be ascribed to the additional oxygen vacancies, stronger surface oxygen migration ability, and better redox properties from α-MnO2. The oxygen vacancies on the catalyst surface provided the main active sites for the chemisorption of CH3SH, and the subsequent electron transfer led to the decomposition of CH3SH. The lattice oxygen on catalysts could be released during the reaction and thus participated in the further oxidation of sulfur-containing species. CH3SSCH3, S0, SO32-, and SO42- were identified as the main products of CH3SH conversion. This work offers a new understanding of the interface interaction mechanism between Mn-based catalysts and S-VOCs.

A Concerted Redox- and Light-Activated Agent for Controlled Multimodal Therapy against Hypoxic Cancer Cells.

Hypoxia represents a remarkably exploitable target for cancer therapy, is encountered only in solid human tumors, and is highly associated with cancer resistance and recurrence. Here, a hypoxia-activated mitochondria-accumulated Ru(II) polypyridyl prodrug functionalized with conjugated azo (Az) and nitrogen mustard (NM) functionalities, RuAzNM, is reported. This prodrug has multimodal theranostic properties toward hypoxic cancer cells. Reduction of the azo group in hypoxic cell microenvironments gives rise to the generation of two primary amine products, a free aniline mustard, and the polypyridyl RuNH2 complex. Thus, the aniline mustard triggers generation of reactive oxygen species (ROS) and mtDNA crosslinking. Meanwhile, the resultant biologically benign phosphorescent RuNH2 gives rise to a diagnostic signal and signals activation of the phototherapy. This multimodal therapeutic effect eventually elevates ROS levels, depletes reduced nicotinamide adenine dinucleotide (NADH) and adenosine triphosphate (ATP), and induces mitochondrial membrane damage, mtDNA damage, and ultimately cell apoptosis. This unique strategy allows controlled multimodal theranostics to be realized in hypoxic cells and multicellular spheroids, making RuAzNM a highly selective and effective cancer-cell-selective theranostic agent (IC50  = 2.3 µm for hypoxic HepG2 cancer cells vs 58.2 µm for normoxic THL-3 normal cells). This is the first report of a metal-based compound developed as a multimodal theranostic agent for hypoxia.

Unraveling the Synergistic Reaction and the Deactivation Mechanism for the Catalytic Degradation of Double Components of Sulfur-Containing VOCs over ZSM-5-Based Materials.

The competitive adsorption behavior, the synergistic catalytic reaction, and deactivation mechanisms under double components of sulfur-containing volatile organic compounds (VOCs) are a bridge to solve their actual pollution problems. However, they are still unknown. Herein, simultaneous catalytic decomposition of methyl mercaptan (CH3SH) and ethyl mercaptan (C2H5SH) is investigated over lanthanum (La)-modified ZSM-5, and kinetic and thermodynamic results confirm a great difference in the adsorption property and catalytic transformation behavior. Meanwhile, the new synergistic reaction and deactivation mechanisms are revealed at the molecular level by combining with in situ diffuse reflectance infrared spectroscopy (in situ DRIFTS) and density functional theory (DFT) calculations. The CH3CH2* and SH* groups are presented in decomposing C2H5SH, while the new species of CH2*, active H* and S*, instead of CH3* and SH*, are proved as the key elementary groups in decomposing CH3SH. The competitive recombining of SH* in C2H5SH with highly active H* in dimethyl sulfide (CH3SCH3), an intermediate in decomposing CH3SH, would aggravate the deposition of carbon and sulfur. La/ZSM-5 exhibits potential environmental application due to the excellent stability of 200 h and water resistance. This work gives an understanding of the adsorption, catalysis, reaction, and deactivation mechanisms for decomposing double components of sulfur-containing VOCs.

Daytime SO2 chemistry on ubiquitous urban surfaces as a source of organic sulfur compounds in ambient air.

The reactions of sulfur dioxide (SO2) with surface-bound compounds on atmospheric aerosols lead to the formation of organic sulfur (OS) compounds, thereby affecting the air quality and climate. Here, we show that the heterogeneous reaction of SO2 with authentic urban grime under near-ultraviolet sunlight irradiation leads to a large suite of various organic compounds including OS released in the gas phase. Calculations indicate that at the core area of Guangzhou, building surface uptake of SO2 is 15 times larger than uptake of SO2 on aerosol surfaces, yielding ~20 ng m-3 of OS that represents an important fraction of the observed OS compounds (60 to 200 ng m-3) in ambient aerosols of Chinese megacities. This chemical pathway occurring during daytime can contribute to the observed fraction of OS compounds in aerosols and improve the understanding of haze formation and urban air pollution.

Heparin-binding protein-enhanced quick SOFA score improves mortality prediction in sepsis patients.

Purpose: The Quick Sequential Organ Failure Assessment (qSOFA) score proposed by Sepsis-3 as a sepsis screening tool has shown suboptimal accuracy. Heparin-binding protein (HBP) has been shown to identify early sepsis with high accuracy. Herein, we aim to investigate whether or not HBP improves the model performance of qSOFA. Methods: We conducted a multicenter prospective observational study of 794 adult patients who presented to the emergency department (ED) with presumed sepsis between 2018 and 2019. For each participant, serum HBP levels were measured and the hospital course was followed. The qSOFA score was used as the comparator. The data was split into a training dataset (n = 556) and a validation dataset (n = 238). The primary endpoint was 30-day all-cause mortality. Results: Compared with survivors, non-survivors had significantly higher serum HBP levels (median: 71.5 ng/mL vs 209.5 ng/mL, p < 0.001). Serum level of HBP weakly correlated with qSOFA class (r 2 = 0.240, p < 0.001). Compared with the qSOFA model alone, the addition of admission HBP level to the qSOFA model significantly improved 30-day mortality discrimination (AUC, 0.70 vs. 0.80; P < 0.001), net reclassification improvement [26% (CI, 17-35%); P < 0.001], and integrated discrimination improvement [12% (CI, 9-14%); P < 0.001]. Addition of C-reactive protein (CRP) level or neutrophil-to-lymphocyte ratio (NLR) to qSOFA did not improve its performance. A web-based mortality risk prediction calculator was created to facilitate clinical implementation. Conclusion: This study confirms the value of combining qSOFA and HBP in predicting sepsis mortality. The web calculator provides a user-friendly tool for clinical implementation. Further validation in different patient populations is needed before widespread application of this prediction model.

Prediction of Dissolved Oxygen Concentration in Sewage Treatment Process Based on Data Recognition Algorithm.

In order to realize the real-time and accurate prediction of dissolved oxygen concentration in the sewage treatment process, a prediction model of dissolved oxygen concentration in the sewage treatment process based on a data identification algorithm was proposed. Combined with the data characteristics of the sewage treatment process, a new sample similarity measure is defined to extract more representative modeling data. In the improved algorithm, in order to improve the quality of the initial members of the basic fireworks algorithm, the chaos algorithm is integrated. The search mechanism of the basic fireworks algorithm is improved, and the optimization process is divided into two stages based on the set criteria, and two groups are used simultaneously. The results show that compared with the basic FWA algorithm, the CFWA algorithm makes better use of the chaotic search mechanism. On the one hand, it avoids the excessive random or blind selection of the initial weight threshold of the neural network in the initial stage; on the other hand, in the optimization process of the weight threshold, two types of search mechanisms, FWA and COA, are used to give full play to their respective strengths and to continuously conduct information exchange and mutual cooperation between groups and individuals. The number of times is better than the basic FWA algorithm, and the training error and generalization error of the CFWA model in the simulation results of the soft sensor model are also better than those of the FWA model, which fully verifies the effectiveness of the CFWA algorithm. It is proved that the data recognition algorithm can effectively predict sewage treatment. It is proved that the data recognition algorithm can effectively predict the dissolved oxygen concentration in wastewater treatment process. It provides a new measurement method for some key process variables that cannot be measured or are difficult to measure in complex chemical processes.

Dynamic changes in heparin-binding protein as a prognostic biomarker for 30-day mortality in sepsis patients in the intensive care unit.

Heparin-binding protein (HBP) has been shown to be a robust predictor of the progression to organ dysfunction from sepsis, and we hypothesized that dynamic changes in HBP may reflect the severity of sepsis. We therefore aim to investigate the predictive value of baseline HBP, 24-h, and 48-h HBP change for prediction of 30-day mortality in adult patients with sepsis. This is a prospective observational study in an intensive care unit of a tertiary center. Patients aged 20 years or older who met SEPSIS-3 criteria were prospectively enrolled from August 2019 to January 2020. Plasma levels of HBP were measured at admission, 24 h, and 48 h and dynamic changes in HBP were calculated. The Primary endpoint was 30-day mortality. We tested whether the biomarkers could enhance the predictive accuracy of a multivariable predictive model. A total of 206 patients were included in the final analysis. 48-h HBP change (HBPc-48 h) had greater predictive accuracy of area under the curve (AUC: 0.82), followed by baseline HBP (0.79), PCT (0.72), lactate (0.71), and CRP (0.65), and HBPc-24 h (0.62). Incorporation of HBPc-48 h into a clinical prediction model significantly improved the AUC from 0.85 to 0.93. HBPc-48 h may assist clinicians with clinical outcome prediction in critically ill patients with sepsis and can improve the performance of a prediction model including age, SOFA score and Charlson comorbidity index.

Physical and chemical characterization of urban grime: An impact on the NO2 uptake coefficients and N-containing product compounds.

Urban grime represents an important environmental surface for heterogeneous reactions in urban environment. Here, we assess the physical and chemical properties of urban grime collected during six consecutive months in downtown of Guangzhou, China. There is a significant variation of the uptake coefficients of NO2 on the urban grime as a function of the relative humidity (RH). In absence of water molecules (0% RH), the light-induced uptake coefficients of NO2 on urban grime samples collected during six months are very similar in order of ≈10-6. At 80% RH, depending on the sampling month the light-induced uptake coefficient of NO2 can reach one order of magnitude higher values (1.5 × 10-5, at 80% RH) compared to those uptakes at 0% RH. In presence of 80% RH, there are strong correlations between the measured NO2 uptakes and the concentrations of the water soluble carbon, soluble anions, polycyclic aromatic hydrocarbons and n-alkanes depicted in the urban grime. These correlations, demonstrate that surface adsorbed water on urban grime play an important role for the uptakes of NO2. The heterogeneous conversion of NO2 on two-month old urban grime under sunlight irradiation (68 W m-2, 300 nm < λ < 400 nm) at 60% RH leads to the formation of unprecedented HONO surface flux of 4.7 × 1010 molecules cm-2 s-1 which is higher than all previously observed HONO fluxes, thereby affecting the oxidation capacity of the urban atmosphere. During the heterogeneous chemistry of NO2 with urban grime, the unsaturated and N-containing organic compounds are released in the gas phase which can affect the air quality in the urban environment.

Inorganic Ions Enhance the Number of Product Compounds through Heterogeneous Processing of Gaseous NO2 on an Aqueous Layer of Acetosyringone.

Methoxyphenols represent important pollutants that can participate in the formation of secondary organic aerosols (SOAs) through chemical reactions with atmospheric oxidants. In this study, we determine the influence of ionic strength, pH, and temperature on the heterogeneous reaction of NO2 with an aqueous film consisting of acetosyringone (ACS), as a proxy for methoxyphenols. The uptake coefficient of NO2 (50 ppb) on ACS (1 × 10-5 mol L-1) is γ = (9.3 ± 0.09) × 10-8 at pH 5, and increases by one order of magnitude to γ = (8.6 ± 0.5) × 10-7 at pH 11. The lifetime of ACS due to its reaction with NO2 is largely affected by the presence of nitrate ions and sulfate ions encountered in aqueous aerosols. The analysis performed by membrane inlet single-photon ionization-time-of-flight mass spectrometry (MI-SPI-TOFMS) reveals an increase in the number of product compounds and a change of their chemical composition upon addition of nitrate ions and sulfate ions to the aqueous thin layer consisting of ACS. These outcomes indicate that inorganic ions can play an important role during the heterogeneous oxidation processes in aqueous aerosol particles.

Nanoarchitectonics of Ni/CeO2 Catalysts: The Effect of Pretreatment on the Low-Temperature Steam Reforming of Glycerol.

CeO2 nanosphere-supported nickel catalysts were prepared by the wetness impregnation method and employed for hydrogen production from glycerol steam reforming. The dried catalyst precursors were either reduced by H2 after thermal calcination or reduced by H2 directly without calcination. The catalysts that were reduced by H2 without calcination achieved a 95% glycerol conversion at a reaction temperature of only 475 °C, and the catalytic stability was up to 35 h. However, the reaction temperature required of catalysts reduced by H2 with calcination was 500 °C, and the catalysts was rapidly inactivated after 25 h of reaction. A series of physicochemical characterization revealed that direct H2 reduction without calcination enhanced the concentration of oxygen vacancies. Thus, the nickel dispersion was improved, the nickel nanoparticle size was reduced, and the reduction of nickel was increased. Moreover, the high concentration of oxygen vacancy not only contributed to the increase of H2 yield, but also effectively reduced the amount of carbon deposition. The increased active nickel surface area and oxygen vacancies synergistically resulted in the superior catalytic performance for the catalyst that was directly reduced by H2 without calcination. The simple, direct hydrogen reduction method remarkably boosts catalytic performance. This strategy can be extended to other supports with redox properties and applied to heterogeneous catalytic reactions involving resistance to sintering and carbon deposition.

Study of the Metal-Support Interaction and Electronic Effect Induced by Calcination Temperature Regulation and Their Effect on the Catalytic Performance of Glycerol Steam Reforming for Hydrogen Production.

Steam reforming of glycerol to produce hydrogen is considered to be the very promising strategy to generate clean and renewable energy. The incipient-wetness impregnation method was used to load Ni on the reducible carrier TiO2 (P25). In the process of catalyst preparation, the interaction and electronic effect between metal Ni and support TiO2 were adjusted by changing the calcination temperature, and then the activity and hydrogen production of glycerol steam reforming reaction (GSR) was explored. A series of modern characterizations including XRD, UV-vis DRS, BET, XPS, NH3-TPD, H2-TPR, TG, and Raman have been applied to systematically characterize the catalysts. The characterization results showed that the calcination temperature can contribute to varying degrees of influences on the acidity and basicity of the Ni/TiO2 catalyst, the specific surface area, together with the interaction force between Ni and the support. When the Ni/TiO2 catalyst was calcined at 600 °C, the Ni species can be produced in the form of granular NiTiO3 spinel. Consequently, due to the moderate metal-support interaction and electronic activity formed between the Ni species and the reducible support TiO2 in the NiO/Ti-600C catalyst, the granular NiTiO3 spinel can be reduced to a smaller Ni0 at a lower temperature, and thus to exhibit the best catalytic performance.

A mitochondrion-targeted BODIPY-Ir(III) conjugate as a photoinduced ROS generator for the oxidative destruction of triple-negative breast cancer cells.

Photodynamic therapy (PDT) provides an alternative option to root out localized triple-negative breast cancer (TNBC) and has been experiencing a surge of research interest over recent years. In this study, we put forward a paradigm of designing novel transition metal-based PSs with the following characteristics: favorable cell-permeability, significant light-harvesting ability and prominent ROS yield. A novel BODIPY-Ir(III) conjugate has been designed as a photoinduced ROS (1O2, ˙OH and ˙O2-) generator. BODIPY-Ir is highly photoactive in subduing cancer cells in the PDT regimen with PI values ranging from 172 to 519 and EC50 in the nanomolar regime. Among various cancerous cell lines, TNBC was especially sensitive to BODIPY-Ir-mediated PDT, with a stunning EC50 value of 4.32 nM (PI = 519) under a moderate flux of visible-light irradiation (500 nm, 10.5 mW cm-2). BODIPY-Ir mainly accumulates in mitochondria and induces cell apoptosis under irradiation. Furthermore, the nanomolar antiproliferative activity of BODIPY-Ir is retained under hypoxia (2.5% O2). This work sheds light on instilling the O2-independent type I mechanism and conferring a red-shift absorption to metal-based PSs which fundamentally facilitate the clinical translation of PSs.

Ruthenium(II) complexes coordinated to graphitic carbon nitride: Oxygen self-sufficient photosensitizers which produce multiple ROS for photodynamic therapy in hypoxia.

The photodynamic therapy (PDT) of cancer is limited by tumor hypoxia as PDT efficiency depends on O2 concentration. A novel oxygen self-sufficient photosensitizer (Ru-g-C3N4) was therefore designed and synthesized via a facile one-pot method in order to overcome tumor hypoxia-induced PDT resistance. The photosensitizer is based on [Ru(bpy)2]2+ coordinated to g-C3N4 nanosheets by Ru-N bonding. Compared to pure g-C3N4, the resulting nanosheets exhibit increased water solubility, stronger visible light absorption, and enhanced biocompatibility. Once Ru-g-C3N4 is taken up by hypoxic tumor cells and exposed to visible light, the nanosheets not only catalyze the decomposition of H2O2 and H2O to generate O2, but also catalyze H2O2 and O2 concurrently to produce multiple ROS (•OH, •O2-, and 1O2). In addition, Ru-g-C3N4 affords luminescence imaging, while continuously generating O2 to alleviate hypoxia greatly improving PDT efficacy. To the best of our knowledge, this oxygen self-sufficient photosensitizer produced via grafting a metal complex onto g-C3N4 is the first of its type to be reported.

Contribution of AMPA Receptor-Mediated LTD in LA/BLA-CeA Pathway to Comorbid Aversive and Depressive Symptoms in Neuropathic Pain.

Comorbid anxiety and depressive symptoms in chronic pain are a common health problem, but the underlying mechanisms remain unclear. Previously, we have demonstrated that sensitization of the CeA neurons via decreased GABAergic inhibition contributes to anxiety-like behaviors in neuropathic pain rats. In this study, by using male Sprague Dawley rats, we reported that the CeA plays a key role in processing both sensory and negative emotional-affective components of neuropathic pain. Bilateral electrolytic lesions of CeA, but not lateral/basolateral nucleus of the amygdala (LA/BLA), abrogated both pain hypersensitivity and aversive and depressive symptoms of neuropathic rats induced by spinal nerve ligation (SNL). Moreover, SNL rats showed structural and functional neuroplasticity manifested as reduced dendritic spines on the CeA neurons and enhanced LTD at the LA/BLA-CeA synapse. Disruption of GluA2-containing AMPAR trafficking and endocytosis from synapses using synthetic peptides, either pep2-EVKI or Tat-GluA2(3Y), restored the enhanced LTD at the LA/BLA-CeA synapse, and alleviated the mechanical allodynia and comorbid aversive and depressive symptoms in neuropathic rats, indicating that the endocytosis of GluA2-containing AMPARs from synapses is probably involved in the LTD at the LA/BLA-CeA synapse and the comorbid aversive and depressive symptoms in neuropathic pain in SNL-operated rats. These data provide a novel mechanism for elucidating comorbid aversive and depressive symptoms in neuropathic pain and highlight that structural and functional neuroplasticity in the amygdala may be important as a promising therapeutic target for comorbid negative emotional-affective disorders in chronic pain.SIGNIFICANCE STATEMENT Several studies have demonstrated the high comorbidity of negative affective disorders in patients with chronic pain. Understanding the affective aspects related to chronic pain may facilitate the development of novel therapies for more effective management. Here, we unravel that the CeA plays a key role in processing both sensory and negative emotional-affective components of neuropathic pain, and LTD at the amygdaloid LA/BLA-CeA synapse mediated by GluA2-containing AMPAR endocytosis underlies the comorbid aversive and depressive symptoms in neuropathic pain. This study provides a novel mechanism for elucidating comorbid aversive and depressive symptoms in neuropathic pain and highlights that structural and functional neuroplasticity in the amygdala may be important as a promising therapeutic target for comorbid negative emotional-affective disorders in chronic pain.

Effect of Inorganic Salts on N-Containing Organic Compounds Formed by Heterogeneous Reaction of NO2 with Oleic Acid.

Fatty acids are ubiquitous constituents of grime on urban and indoor surfaces and they represent important surfactants on organic aerosol particles in the atmosphere. Here, we assess the heterogeneous processing of NO2 on films consisting of pure oleic acid (OA) or a mixture of OA and representative salts for urban grime and aerosol particles, namely Na2SO4 and NaNO3. The uptake coefficients of NO2 on OA under light irradiation (300 nm < λ < 400 nm) decreased with increasing relative humidity (RH), from (1.4 ± 0.1) × 10-6 at 0% RH to (7.1 ± 1.6) × 10-7 at 90% RH. The uptake process of NO2 on OA gives HONO as a reaction product, and the highest HONO production was observed upon the heterogeneous reaction of NO2 with OA in the presence of nitrate (NO3-) ions. The formation of gaseous nitroaromatic compounds was also enhanced in the presence of NO3- ions upon light-induced heterogeneous processing of NO2 with OA, as revealed by membrane inlet single-photon ionization time-of-flight mass spectrometry (MI-SPI-TOFMS). These results suggest that inorganic salts can affect the heterogeneous conversion of gaseous NO2 on fatty acids and enhance the formation of HONO and other N-containing organic compounds in the atmosphere.

Contribution of TRESK two-pore domain potassium channel to bone cancer-induced spontaneous pain and evoked cutaneous pain in rats.

Cancer-associated pain is debilitating. However, the mechanism underlying cancer-induced spontaneous pain and evoked pain remains unclear. Here, using behavioral tests with immunofluorescent staining, overexpression, and knockdown of TRESK methods, we found an extensive distribution of TRESK potassium channel on both CGRP+ and IB4+ nerve fibers in the hindpaw skin, on CGRP+ nerve fibers in the tibial periosteum which lacks IB4+ fibers innervation, and on CGRP+ and IB4+ dorsal root ganglion (DRG) neurons in rats. Moreover, we found a decreased expression of TRESK in the corresponding nerve fibers within the hindpaw skin, the tibial periosteum and the DRG neurons in bone cancer rats. Overexpression of TRESK in DRG neurons attenuated both cancer-induced spontaneous pain (partly reflect skeletal pain) and evoked pain (reflect cutaneous pain) in tumor-bearing rats, in which the relief of evoked pain is time delayed than spontaneous pain. In contrast, knockdown of TRESK in DRG neurons produced both spontaneous pain and evoked pain in naïve rats. These results suggested that the differential distribution and decreased expression of TRESK in the periosteum and skin, which is attributed to the lack of IB4+ fibers innervation within the periosteum of the tibia, probably contribute to the behavioral divergence of cancer-induced spontaneous pain and evoked pain in bone cancer rats. Thus, the assessment of spontaneous pain and evoked pain should be accomplished simultaneously when evaluating the effect of some novel analgesics in animal models. Also, this study provides solid evidence for the role of peripheral TRESK in both cancer-induced spontaneous pain and evoked cutaneous pain.

Analysis of risk factors for different subtypes of acute coronary syndrome.

AIMS: To investigate the different risk factors among different subtypes of patients with acute coronary syndrome (ACS). METHODS: A total of 296 patients who had ACS were retrospectively enrolled. Blood and echocardiographic indices were assessed within 24 hours after admission. Differences in risk factors and Gensini scores of coronary lesions among three groups were analyzed. RESULTS: Univariate analysis of risk factors for ACS subtypes showed that age, and levels of fasting plasma glucose, amino-terminal pro-brain natriuretic peptide, and creatine kinase isoenzyme were significantly higher in patients with non-ST-segment elevation myocardial infarction (NSTEMI) than in those with unstable angina pectoris (UAP). Logistic multivariate regression analysis showed that amino-terminal pro-brain natriuretic peptide and the left ventricular ejection fraction (LVEF) were related to ACS subtypes. The left ventricular end-diastolic diameter was an independent risk factor for UAP and ST-segment elevation myocardial infarction (STEMI) subtypes. The severity of coronary stenosis was significantly higher in NSTEMI and STEMI than in UAP. Gensini scores in the STEMI group were positively correlated with D-dimer levels (r = 0.429) and negatively correlated with the LVEF (r = -0.602). CONCLUSION: Different subtypes of ACS have different risk factors. Our findings may have important guiding significance for ACS subtype risk assessment and clinical treatment.