Effects of increasing sensitizing doses of ovalbumin on airway hyperresponsiveness in asthmatic mice.

BACKGROUND: The dosage of ovalbumin (OVA) during the sensitization stage is considered a crucial factor in the development of airway hyperresponsiveness (AHR). However, the inconsistent dosages of sensitizing OVA used in current studies and the lack of research on their impact on AHR are notable limitations. METHODS: We examined the impact of increasing sensitizing doses of OVA in a murine asthma model, which entailed initial sensitization with OVA followed by repeated exposure to OVA aerosols. BALB/c mice were primed with doses of OVA (0, 10, 20, 50, and 100 µg) plus 1 mg Alum on Days 0 and 7, and were challenged with OVA aerosols (10 mg/mL for 30 min) between Days 14 and 17. Antigen-induced AHR to methacholine (MCh), as well as histological changes, eosinophilic infiltration, and epithelial injury were assessed. RESULTS: The result indicated that there are striking OVA dose-related differences in antigen-induced AHR to MCh. The most intense antigen-induced AHR to MCh was observed with sensitization at 50 µg, while weaker responses were seen at 10, 20, and 100 µg. Meanwhile, there was a significant increase in eosinophil count with sensitization at 50 µg. The changes of AHR were correlated with total cells count, lymphocytes count, eosinophils count, and basophils count in bronchoalveolar lavage fluid; however, it did not correlate with histological changes such as cellular infiltration into bronchovascular bundles and goblet cell hyperplasia of the bronchial epithelium. CONCLUSION: Overall, this study demonstrated that sensitization with 50 µg of OVA resulted in the most significant AHR compared to other dosages. These findings may offer valuable insights for future research on mouse asthma modeling protocols.

Efficacy of five-step shoulder manipulation for rotator cuff-related shoulder pain: protocol for a multicenter randomized controlled trial.

BACKGROUND: Rotator cuff-related shoulder pain (RCRSP) is the most common cause of shoulder disorders. In China, manipulation has been used extensively for the treatment of patients with RCRSP. However, high-quality clinical evidence to support the therapeutic effect of manipulation is still limited. METHODS: A multicenter, participant-, outcome assessor-, and data analyst-blinded, randomized, placebo-controlled trial will be conducted. A total of 280 participants with RCRSP will be recruited from three hospitals and randomly assigned to a five-step shoulder manipulation (FSM) group or a sham manipulation (SM) group. Each group will receive four weekly treatment sessions, with all participants performing exercises at home for 12 weeks. Assessments, namely the Constant-Murley score, visual analog scale, range of motion, and 36-Item Short Form Survey, will be made at baseline, 4, 12, 18, and 24 weeks. Adverse events during the study will also be recorded. DISCUSSION: This is a pragmatic clinical trial to evaluate the efficacy and safety of FSM in patients with RCRSP. The findings of this study will provide worthy clinical evidence for manual therapy for RCRSP. TRIAL REGISTRATION: China Registered Clinical Trial Registration Center ChiCTR2000037577. Registered on 29 August 2020.

Undiagnosed Long COVID-19 in China Among Non-vaccinated Individuals: Identifying Persistent Symptoms and Impacts on Patients' Health-Related Quality of Life.

Is Long COVID-19 under-diagnosed? The definition of this new condition has received many contributions, and it is still under development as a great variety of symptoms have been associated to it. This study explores the possibility that there are non-diagnosed cases among individuals who have been infected by SARS-CoV-2 and have not been vaccinated. The long-term symptoms identified among a sample 255 individuals have been associated to Long COVID-19 by recent literature. The study relates these symptoms to risk factors and health-related quality of life (HRQoL) negative impacts. The individuals were screened 1 year after discharge to explore its potential relation to Long COVID-19. Patients diagnosed with COVID-19 and discharged from designated hospitals in a Chinese province between January and April 2020 were included in this study. They received computed tomography (CT) scans one month after discharge. One year after discharge, patients were invited to physical examination and interviewed with questionnaire on health-related quality of life (HRQoL) and post-COVID-19 symptoms. Tobit regression and Logistic regression were applied to evaluate the risk factors for health utility value and pain/discomfort and anxiety/depression. One year after discharge, 39.61% patients complained of several of the symptoms associated to Long COVID-19. More than half had abnormal chest CT. Previous studies focused on the post-COVID-19 symptoms and chest CT findings of patients, but few studies have assessed the COVID-19-associated risk factors for health-related quality of life.

Is there a gap between artificial intelligence applications and priorities in health care and nursing management?

AIM: The article aims to outline a contrast between three priorities for nursing management proposed a decade ago and key features of the following 10 years of developments on artificial intelligence for health care and nursing management. This analysis intends to contribute to update the international debate on bridging the essence of health care and nursing management priorities and the focus of artificial intelligence developers. BACKGROUND: Artificial intelligence research promises innovative approaches to supporting nurses' clinical decision-making and to conduct tasks not related to patient interaction, including administrative activities and patient records. Yet, even though there has been an increase in international research and development of artificial intelligence applications for nursing care during the past 10 years, it is unclear to what extent the priorities of nursing management have been embedded in the devised artificial intelligence solutions. EVALUATION: Starting from three priorities for nursing management identified in 2011 in a special issue of the Journal Nursing Management, we went on to identify recent evidence concerning 10 years of artificial intelligence applications developed to support health care management and nursing activities since then. KEY ISSUE: The article discusses to what extent priorities in health care and nursing management may have to be revised while adopting artificial intelligence applications or, alternatively, to what extent the direction of artificial intelligence developments may need to be revised to contribute to long acknowledged priorities of nursing management. CONCLUSION: We have identified a conceptual gap between both sets of ideas and provide a discussion on the need to bridge that gap, while admitting that there may have been recent field developments still unreported in scientific literature. IMPLICATIONS FOR NURSING MANAGEMENT: Artificial intelligence developers and health care nursing managers need to be more engaged in coordinating the future development of artificial intelligence applications with a renewed set of nursing management priorities.

Electroacupuncture at ST36 (Zusanli) Prevents T-Cell Lymphopenia and Improves Survival in Septic Mice.

Purpose: Sepsis is the main cause of death in intensive care unit. Maladaptive cytokine storm and T-cell lymphopenia are critical prognosis predictors of sepsis. Electroacupuncture (EA) is expected to be an effective intervention to prevent sepsis. This study aims to determine the potential of EA at ST36 (Zusanli) to prevent experimental septic mice. Methods: Mice were randomly assigned into PBS, LPS, or EA+LPS group. EA (0.1 mA, continuous wave, 10 Hz) was performed stimulating the ST36 for 30 min, once a day for 3 days. After the third day, all mice were challenged with PBS or LPS (4 mg/kg) simultaneously. Mice were evaluated for survival, ear temperature, and other clinical symptoms. Lung and small intestine tissue injuries were analyzed by hematoxylin and eosin staining. Bio-Plex cytokine assay was used to analyze the concentration of cytokines. T lymphocytes were analyzed by flow cytometry and Western blot assays. The role of T cells in preventing sepsis by EA was analyzed by using nude mice lacking T lymphocytes. Results: EA at ST36 improved survival, symptom scores, and ear temperature of endotoxemic mice. EA also improved dramatically pulmonary and intestinal injury by over 50% as compared to untreated mice. EA blunted the inflammatory cytokine storm by inducing a lasting inhibition of the production of major inflammatory factors (TNF-α, IL-1ß, IL-5, IL-6, IL-10, IL-17A, eotaxin, IFN-γ, MIP-1ß and KC). Flow cytometry and Western blot analyses showed EA significantly reduced T-lymphocyte apoptosis and pyroptosis. Furthermore, T lymphocytes were critical for the effects of EA at ST36 stimulation blunted serum TNF-α levels in wild-type but not in nude mice. Conclusion: EA halted systemic inflammation and improved survival in endotoxemic mice. These effects are associated with the protective effect of EA on T lymphocytes, and T cells are required in the anti-inflammatory effects of EA in sepsis.

Inhibitory Effect of S100A11 on Airway Smooth Muscle Contraction and Airway Hyperresponsiveness.

OBJECTIVE: S100A11 is a member of the S100 calcium-binding protein family and has intracellular and extracellular regulatory activities. We previously reported that S100A11 was differentially expressed in the respiratory tracts of asthmatic rats as compared with normal controls. Here, we aimed to analyze the potential of S100A11 to regulate both allergen-induced airway hyperresponsiveness (AHR) as well as acetylcholine (ACh)-induced hypercontractility of airway smooth muscle (ASM) and contraction of ASM cells (ASMCs). METHODS: Purified recombinant rat S100A11 protein (rS100A11) was administered to OVA-sensitized and challenged rats and then the AHR of animals was measured. The relaxation effects of rS100A11 on ASM were detected using isolated tracheal rings and primary ASMCs. The expression levels of un-phosphorylated myosin light chain (MLC) and phosphorylated MLC in ASMCs were analyzed using Western blotting. RESULTS: Treatment with rS100A11 attenuated AHR in the rats. ASM contraction assays showed that rS100A11 reduced the contractile responses of isolated tracheal rings and primary ASMCs treated with ACh. In addition, rS100A11 markedly decreased the ACh-induced phosphorylation of the myosin light chain in ASMCs. Moreover, rS100A11 also suppressed the contractile response of tracheal rings in calcium-free buffer medium. CONCLUSION: These results indicate that S100A11 protein can relieve AHR by relaxing ASM independently of extracellular calcium. Our data support the idea that S100A11 is a potential therapeutic target for reducing airway resistance in asthma patients.

[Research progress of lung natural killer cells and their roles in pulmonary diseases].

Lung natural killer (NK) cells can be classified into tissue-resident NK (trNK) cells and conventional NK (cNK) cells. Both trNK and cNK are composed of multiple subsets with unique phenotypes and functional characteristics. However, the phenotypic and functional differences between the two captured less attention. The features of trNK and cNK in the development, phenotypes and functions are sorted, and the interactions between NK cells and other immune cells in the lung are presented. Moreover, the latest research progress of lung NK cells in lung infections, tumors, transplantation, asthma and other diseases is particularly highlighted. It suggests that trNK cells may play a significant role, although lung NK cells are mainly composed of cNK. Further investigations of lung trNK and cNK cells will provide new insights into NK cell-based disease research.

Research hotspot and frontier analysis of traditional Chinese medicine in asthma using bibliometric methods from 1991 to 2021.

Traditional Chinese medicine (TCM) has been successfully used to treat asthmatic conditions for centuries. Nevertheless, the current hotspots and research frontiers on TCM for asthma have not been systematically investigated on the basis of bibliometric analysis. In this study, a scientometric analysis (1991-2021) was carried out on 3081 journal articles obtained from the Web of Science Core Collection database to explore the basic characteristics, research hotspots, and frontiers of TCM in asthma research. The results revealed the following: (1) Research on TCM in asthma has received widespread attention since the beginning of the 21st century; perhaps 2009 was an important turning point. TCM in asthma research shows a trend of interdisciplinary development. (2) Well-known universities/institutions in China, the United States, and South Korea have conducted the main body of current TCM research in asthma. JingCheng Dong (Fudan University, China) and XiuMin Li (Mount Sinai School of Medicine, USA) are the top 2 leading authors in this field. However, there is still a lack of international cooperation in the field of TCM in asthma research, and the influence of researchers in China and South Korea still needs improvement. (3) The Journal of Allergy and Clinical Immunology ranks first in the research field on the influence of TCM in asthma. (4) Hotspots and frontiers of TCM in asthma are provided according to the timeline analyses of the research. In the former, complementary medicine, alternative treatment, allergic rhinitis, airway remodeling, Dietary Approach to Stop Hypertension diet, and eosinophilic esophagitis are in the exploratory stage. In the latter, pharmacology, essential oil, gut microbiota, and oxidative stress were investigated from 2006 until late 2021 as period B, which contradicts period A (1991-2005). Moreover, limitations of this bibliometric analysis and the study of TCM research in asthma still exist, which are sufficiently important to warrant further investigations. Finally, we propose the significant importance of the real quintessence and characteristics of TCM in clinical and future research.

A Simulation Analyzing Approach to Estimating the Probability of Airborne Infection Risks in Railway Station Platform Coupling with the Wells-Riley Model and Pathfinder Model.

Railway station platforms present a particular challenge, especially during a train departure or arrival where some passengers may have potential conditions that make them vulnerable to airborne infections due to the high density and close proximity of passengers. This study presented a simulation analyzing approach to estimating the probability of airborne infection risks in station platform spaces coupling with the Wells-Riley model and Pathfinder model. We examine the impact of overcrowded area of the station platform on infection rates under various traces of evacuation. The result of the potential risk for three modes is discussed, and the results of the standard model under the same parameter setting are optimised. Next, the impact of the ventilated volume based on uneven distribution of individuals and the exposure time based on evacuation on the infection risk in platform spaces are studied. The relationship between platform spaces overcrowding and the infection risk provided further insights to observe the supporting information.

Cyclophilin A Plays Potential Roles in a Rat Model of Asthma and Suppression of Immune Response.

PURPOSE: Cyclophilin A (CypA) inhibits CD4+ T cell signal transduction via interleukin-2-inducible T-cell kinase (Itk), a tyrosine kinase required for T helper (Th) 2 cells function. Furthermore, mice with CypA silencing developed allergic diseases associated with increased Th2 cytokines production. CD4+ T cells with a Th2-cytokine pattern have been demonstrated to have a pivotal role in the pathogenesis of asthma. However, the effects of CypA in regulating immunity in asthma and in relieving asthmatic symptoms in vivo are entirely unknown. METHODS: Recombinant CypA protein (rCypA) was generated and purified. Ovalbumin (OVA)-challenged asthmatic rats model and acetylcholine chloride (ACh)-induced contraction of tracheal spirals were established. The pulmonary resistance (RL) value of asthmatic rats in vivo and the isometric tension of tracheal spirals ex vivo were recorded by MFLab 3.01 software. The levels of Th1 and Th2 cytokines and the quantities of immunoglobulin (IgA, IgG, IgM and IgE) in the supernatants of rat spleen lymphocytes were detected and analysed by bio-plex Suspension Array System and ELISA, respectively. CD4+ T cells were separated by MicroBeads, and the levels of interleukin (IL)-4 and interferon-γ (IFN-γ) were detected by ELISA. RESULTS: rCypA (10 ng/kg) significantly reduced RL within 2-7 min in OVA-challenged asthmatic rats in vivo, and there were no significant differences compared with terbutaline (TB) and hydrocortisone (HC). Furthermore, rCypA (10 ng/mL) significantly reduced the isometric tension in the ACh-induced contraction of the tracheal spiral ex vivo, and the effect of rCypA was better than that of TB. Additionally, rCypA suppressed the secretion of both Th1 and Th2 cytokines, and the suppressive effects of rCypA were stronger than those of HC, especially on Th2 cytokines. CONCLUSION: These findings indicate that CypA may serve as a potential novel therapeutic strategy for asthma.

Carboxylation of sodium arylsulfinates with CO2 over mesoporous K-Cu-20TiO2.

A mesoporous ternary metal oxide (K-Cu-20TiO2) from a simple sol-gel method was prepared to catalyze heterogeneously the carboxylation reaction of various sodium arylsulfinates under atmospheric carbon dioxide. The catalyst showed excellent selectivity and good functional group tolerance to carboxylation recycle. The oxidation state of active copper(i) by characterization using FTIR, XRD, TG, XPS and TEM techniques proved to be efficacious to conduct atom economical reactions.

Acupuncture in a Rat Model of Asthma.

A high platform can fix rats without restriction and completely expose the acupoints on the back during acupuncture manipulation. This article describes methods for the fabrication of the high platform, establishes a rat model of asthma and measures changes in respiratory function using a noninvasive and real-time whole-body plethysmography (WBP) system.

Discovery of potential asthma targets based on the clinical efficacy of Traditional Chinese Medicine formulas.

ETHNOPHARMACOLOGICAL RELEVANCE: Standard therapy for asthma, a highly heterogeneous disease, is primarily based on bronchodilators and immunosuppressive drugs, which confer short-term symptomatic relief but not a cure. It is difficult to discover novel bronchodilators, although potential new targets are emerging. Traditional Chinese Medicine (TCM) formulas have been used to treat asthma for more than 2000 years, forming the basis for representative asthma treatments. AIM OF THE STUDY: Based on the efficacy of TCM formulas, anti-asthmatic herbal compounds bind proteins are potential targets for asthma therapy. This analysis will provide new drug targets and discovery strategies for asthma therapy. MATERIALS AND METHODS: A list of candidate herbs for asthma was selected from the classical formulas (CFs) of TCM for the treatment of wheezing or dyspnea recorded in Treatise on Cold Damage and Miscellaneous Diseases (TCDMD) and from modern herbal formulas identified in the SAPHRON TCM Database using the keywords "wheezing" or "dyspnea". Compounds in the selected herbs and compounds that directly bind target proteins were acquired by searching the Herbal Ingredients' Targets Database (HITD), TCM Data Bank (TCMDB) and TCM Integrated Database (TCMID). Therapeutic targets of conventional medicine (CM) for asthma were collected by searching Therapeutic Target Database (TTD), DrugBank and PubMed as supplements. Finally, the enriched gene ontology (GO) terms of the targets were obtained using the Database for Annotation Visualization and Integrated Discovery (DAVID) and protein-protein interactions (PPI) networks were constructed using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING). The effects of two selected TCM compounds, kaempferol and ginkgolide A, on cellular resistance in human airway smooth muscle cells (ASMCs) and pulmonary resistance in a mouse model were investigated. RESULTS: The list of 32 candidate herbs for asthma was selected from 10 CFs for the treatment of wheezing or dyspnea recorded in TCDMD and 1037 modern herbal formulas obtained from the SAPHRON TCM Database. A total of 130 compounds from the 32 selected herbs and 68 herbal compounds directly bind target proteins were acquired from HITD and TCMDB. Eighty-eight therapeutic targets of CM for asthma were collected by searching TTD and PubMed as supplements. DAVID and STRING analyses showed targets of TCM formulas are primarily related to cytochrome P450 (CYP) family, transient receptor potential (TRP) channels, matrix metalloproteinases (MMPs) and ribosomal protein. Both TCM formulas and CM act on the same types of targets or signaling pathways, such as G protein-coupled receptors (GPCRs), steroid hormone receptors (SHRs), and JAK-STAT signaling pathway. The proteins directly targeted by herbal compounds, TRPM8, TRPA1, TRPV3, CYP1B1, CYP2B6, CYP1A2, CYP3A4, CYP1A1, PPARA, PPARD, NR1I2, MMP1, MMP2, ESR1, ESR2, RPLP0, RPLP1 and RPLP2, are potential targets for asthma therapy. In vitro results showed kaempferol (1 × 10-2 mM) and ginkgolide A (1 × 10-5 mM) significantly increased the cell index (P < 0.05 vs. histamine, n = 3) and therefore relaxed human ASMCs. In vivo results showed kaempferol (145 µg/kg) and ginkgolide A (205 µg/kg) significantly reduced pulmonary resistance (P < 0.05 vs. methacholine, n = 6). CONCLUSION: Potential target discovery for asthma treatment based on the clinical effectiveness of TCM is a feasible strategy.

Classic Chinese Acupuncture versus Different Types of Control Groups for the Treatment of Chronic Pain: Review of Randomized Controlled Trials (2000-2018).

OBJECTIVE: To review the effectiveness of classic Chinese acupuncture in the treatment of chronic pain by comparing treatment groups with different types of control groups in accordance with the newly published guidelines for systematic reviews. METHODS: We searched EMBASE, PubMed, and the Cochrane Central Register of Controlled Trials databases from 2000 to 2018. We included randomized controlled trials that included acupuncture as the sole treatment or as an adjunctive treatment for chronic pain. The outcome was pain intensity measured by the visual analogue scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale, 11-point numeric rating scale (NRS), and other tools. Two researchers conducted the study selection, data extraction, and quality assessment processes independently. Disagreements were solved by discussion and reanalysis of the data. The quality of all included studies was evaluated using the CBNG (the Cochrane Back and Neck Group) and the STRICTA (Standards for Reporting Interventions in Controlled Trials of Acupuncture) checklists. RESULTS: Sixty-one studies were fully analyzed and ranked based on the newest STRICTA and CBNG standards. We found good evidence that receiving acupuncture is better than not receiving treatment or being placed on a waiting list and reasonable evidence that it is better than conventional or usual care. Limited evidence was found regarding placebo treatments that involve the expectation of needling (real or fake). CONCLUSION: Sham acupuncture may not be appropriate as a control intervention for assessing the effectiveness of acupuncture. Acupuncture effectiveness in controlling chronic pain is still limited due to the low quality of the studies published.

Burden of typical diseases attributed to the sources of PM2.5-bound toxic metals in Beijing: An integrated approach to source apportionment and QALYs.

PM2.5-bound toxic metals (TMs) are derived from various sources, and they can cause many adverse health effects on the human body. To effectively reduce the disease burden of TMs by controlling the relative sources, an integrated approach of quality-adjusted life years (QALYs) and source-apportionment (positive matrix factorization, PMF) was proposed and applied to some typical diseases induced by TMs in 2017 in Beijing. The estimation included two parts; first, the number of potentially affected people was calculated based on the source mass contribution from PMF and the inhalation unit risk of TMs; second, the QALYs lost per affected person was calculated based on the disease duration, expected years of life lost (EYLL) and quality of life (QoL) for both affected people and the general population. The results showed that QALYs lost per person for renal cancer (17.3 QALYs), pneumonia (14.4 QALYs), lung cancer (14.2 QALYs), skin cancer (12.7 QALYs) and diabetes mellitus (12.6 QALYs) were higher than those for other diseases. Combined with PMF, the source contributions to the overall burden of typical diseases from the TMs followed the order of coal combustion (50.2%) > vehicle emissions (24.4%) > fuel oil combustion (11.4%) > Cr-related industry (10.9%) > resuspended dust (3.0%). The rank was further compared with that assessed for noncancer and cancer risks, and we verified the reasonability of the QALYs method. For seasonal contributions to coal combustion, winter and spring had the highest contributions, which coincided with the fact that coal was the main fuel for heating in Beijing. The QALYs lost attributed to TMs for coal combustion decreased by 49.1% from 2016 to 2017, which may indicate an effective policy associated with coal control. Overall, the integrated approach was successfully employed for estimating the disease burden induced by TMs from each source and was an effective solution to identify the control rank of sources for TM reduction.

What Is the Appropriate Acupuncture Treatment Schedule for Chronic Pain? Review and Analysis of Randomized Controlled Trials.

BACKGROUND: Acupuncture is widely used for the treatment of chronic pain. Different protocols of acupuncture practice exist and lack agreement on the optimal schedule of acupuncture treatment. OBJECTIVE: To review the appropriate acupuncture treatment schedule for chronic pain. METHODS: Embase, Pubmed, Cochrane Central Register of Controlled Trials, and reference lists were searched from 2009 to 2018 to identify randomized controlled trials of acupuncture for chronic pain conditions. We collected factors of treatment schedule (D, duration of each treatment session; N, number of treatment sessions; T, total duration of treatment in weeks) from each of the trials, and the linear regression analysis with real pain relief rate (both treatment and follow-up) was performed. Furthermore, we recommend the concept of "DOSE" and frequency (F) to evaluate the dose and frequency effect of acupuncture. RESULTS: Twenty-four trials with a total number of 3461 patients met the inclusion criteria. Of these, data from 23 studies were available for analysis. Firstly, the results showed that follow-up pain relief rate was decreased slightly with the increase of the duration of each session and DOSE (r=-0.3414 and r=-0.3246, respectively), but those two factors had no correlation with the pain relief rate after treatment. Secondly, it showed that either lower frequency with 2 sessions/week and higher frequency greater than 2 sessions/week or DOSE of 30 mins/week can achieve higher pain relief rate after treatment. Thirdly, we found the rate of pain relief remained at a high level greater than 20% up to 18 weeks after the treatment, and then it dropped sharply below 10% with the follow-up extended. A positive relationship was found between study score and pain relief both in treatment and follow-up (r=0.4654 and r=0.3046, respectively). CONCLUSIONS: The effect of acupuncture varies greatly with the different schedules of acupuncture, so it is necessary to review and choose the appropriate schedule. Although the current work is based on a limited number of trials, the findings suggest that acupuncture has a dose and frequency effect presenting within a certain range, which would have considerable implications for the design and interpretation of clinical trials. More high-quality randomized controlled trials on acupuncture schedule research were needed for providing more definitive evidence.

Implications of seasonal control of PM2.5-bound PAHs: An integrated approach for source apportionment, source region identification and health risk assessment.

PM2.5-bound PAHs are ubiquitous in urban atmospheres and are characterized as carcinogenic, teratogenic and mutagenic upon inhalation. A total of 218 daily PM2.5 samples were collected during one year in the urban district of Beijing, China. Analysis showed that the annual mean concentration of total PAHs (TPAHs) was 66.2 ng/m3, with benzo(a)pyrene (BaP) accounting for 12.4%. High-molecular-weight (HMW, 4-6 rings) PAHs were the dominant components. Seasonal TPAH concentrations decreased in the order of heating season (156 ng/m3) > autumn (20.4 ng/m3) > spring (16.0 ng/m3) > summer (12.5 ng/m3) and were related to meteorological conditions and source emission intensity. The source-attributed mass contribution and source regions of three sources (i.e., (1) vehicle emissions; (2) coal combustion; and (3) petroleum volatilization, natural gas and biomass combustion) were identified by integrating the positive matrix factorization (PMF), potential source contribution function (PSCF) and conditional probability function (CPF). Vehicle emissions contributed the most mass (54.6%), followed by coal combustion (29.8%), on an annual basis. Combined with actual regional emissions, vehicle emissions were mainly derived from local sources, while coal combustion mainly came from regional transport from surrounding areas. Vehicle emissions and coal combustion have much higher mass contributions in the heating season. The source-attributed cancer risk was further evaluated based on source mass contribution and inhalation unit risk. Vehicle emissions contributed the largest risk (2.8 × 10-6, accounting for 71%) as a result of 30 years of exposure for local residents, exceeding the acceptable level (10-6). The heating season showed the most risk, especially in response to vehicle emissions and coal combustion. Overall, the source-attributed cancer risk was regarded as the better index for the development of a control strategy of PM2.5-bound PAHs for protecting residents. Based on this index, priority control sources in each season were identified to supply a more effective management solution.

Levels and health risks of PM2.5-bound toxic metals from firework/firecracker burning during festival periods in response to management strategies.

Daily PM2.5 was collected in the periods before, during and after the Chinese Spring Festival (CSF) in both 2016 and 2018 to clarify the annual variation in the concentrations and health risks of toxic metals under different firework/firecracker (FF) management strategies. PM2.5 and bound metals all decreased during the CSF from 2016 to 2018. According to relative abundance analysis, toxic metals, i.e., Ba, Pb, Cu and Cr, showed obvious peak concentrations and abundance levels on intensive FF burning days, i.e., New Year's Eve, Chinese New Year and the Lunar Festival. In both CSF periods, three sources of toxic metals, namely, FF burning, coal combustion, and resuspended dust and vehicle emissions, were identified by positive matrix factorization (PMF). Among them, the mass contribution of FF decreased from 0.83 µg m-3 (11%) in the 2016 CSF to 0.23 µg m-3 (9.0%) in the 2018 CSF. The FF-attributed noncancer and cancer risks due to metals for residents under long-term exposure were 0.02 (19.9%) and 1.76 × 10-7 (17.9%) in the 2016 CSF and 0.01 (20.2%) and 8.59 × 10-8 (14.7%) in the 2018 CSF. Although a policy shift from "restriction" to "prohibition" regarding FF has indeed decreased toxic metal concentrations and health risk, Cr(VI) and Ba should be examined more closely in the future because they have become dominant contributors to cancer risk and noncancer risk, respectively.

Copper-Catalyzed Regioselective and Stereoselective Coupling of Grignard Reagents with Pent-1-en-4-yn-3-yl Benzoates: A Shortcut to ( Z) -1,5-Disubstituted Pent-3-en-1-ynes from Accessible Starting Materials.

Copper-catalyzed coupling of Grignard reagents with pent-1-en-4-yn-3-yl benzoates occurs regioselectively at the terminal alkenyl carbon rather than the alkynyl site, leading to the stereoselective formation of unexpected ( Z) -1,5-disubstituted pent-3-en-1-ynes without generation of the initially expected alkenyl allene products. By using easily accessible starting materials, this reaction can provide direct access to thermodynamically unfavorable Z-configured enynes, which widely exist in many bioactive natural products, such as the anti-inflammatory components in henna.

Emission control priority of PM2.5-bound heavy metals in different seasons: A comprehensive analysis from health risk perspective.

Source-specific health risks of PM2.5-bound metals were analyzed for emission control by integrating source apportionment with health risk assessments of residents affected via inhalation pathways. A total of 218 daily PM2.5 samples were collected in 2016 in the central urban district of Beijing, China. Analyses showed that the mean annual concentrations of total heavy metals (THMs) and PM2.5 were 0.39 and 104.37 µg m-3, respectively. The heating season had significantly higher concentrations of THMs and PM2.5 (0.61, 134 µg m-3) than the non-heating season (0.27, 88.1 µg m-3) (p < 0.05). Among all metals, arsenic had the largest incremental cancer risk of 7.04 × 10-6. Six sources were identified by positive matrix factorization combined with conditional probability function and potential source contribution function analyses. The order of contribution to PM2.5-bound metal concentrations was resuspended dust (61.0%), traffic emission (16.3%), Cu-related industry (14.1%), coal combustion (3.7%), Cr-related industry (3.4%), and fuel oil combustion (1.6%). During the heating season, the contribution of coal combustion decreased slightly, which may have been due to the countermeasure of substituting coal for gas or electric heat in 2016. However, in terms of cancer risk contribution, coal combustion was the top contributor in both heating (3.5 × 10-6, 51.6%) and non-heating (2.7 × 10-6, 59.6%) seasons due to high attributable contents of the toxic metals, As, Cd and Pb. The Cr-related and Cu-related industries were the next controlled sources in the heating and non-heating seasons, respectively. Thus, these sources should receive priority in the development of control measures.