MiR-421 mediates PM2.5-induced endothelial dysfunction via crosstalk between bronchial epithelial and endothelial cells.

OBJECTIVE: PM2.5 is closely linked to vascular endothelial injury and has emerged as a major threat to human health. Our previous research indicated that exposure to PM2.5 induced an increased release of miR-421 from the bronchial epithelium. However, the role of miR-421 in PM2.5-induced endothelial injury remains elusive. MATERIALS AND METHODS: We utilized a subacute PM2.5-exposure model in mice in vivo and an acute injury cell model in vitro to simulate PM2.5-associated endothelial injury. We also used quantitative real-time polymerase chain reaction, western blot, enzyme-linked immunosorbent assay, and immunohistochemistry to investigate the role of miR-421 in PM2.5-induced endothelial injury. RESULTS: Our findings reveal that inhibition of miR-421 attenuated PM2.5-induced endothelial injury and hypertension. Mechanistically, miR-421 inhibited the expression of angiotensin-converting enzyme 2 (ACE2) in human umbilical vein endothelial cells and upregulated the expression of the downstream molecule inducible nitric oxide synthase (iNOS), thereby exacerbating PM2.5-induced endothelial injury. CONCLUSIONS: Our results indicate that PM2.5 exposure facilitates crosstalk between bronchial epithelial and endothelial cells via miR-421/ACE2/iNOS signaling pathway, mediating endothelial damage and hypertension. MiR-421 inhibition may offer a new strategy for the prevention and treatment of PM2.5-induced vascular endothelial injury.

Engaging stakeholders to level up COPD care in LMICs: lessons learned from the "Breathe Well" programme in Brazil, China, Georgia, and North Macedonia.

BACKGROUND: Effective stakeholder engagement in health research is increasingly being recognised and promoted as an important pathway to closing the gap between knowledge production and its use in health systems. However, little is known about its process and impacts, particularly in low-and middle-income countries. This opinion piece draws on the stakeholder engagement experiences from a global health research programme on Chronic Obstructive Pulmonary Disease (COPD) led by clinician researchers in Brazil, China, Georgia and North Macedonia, and presents the process, outcomes and lessons learned. MAIN BODY: Each country team was supported with an overarching engagement protocol and mentored to develop a tailored plan. Patient involvement in research was previously limited in all countries, requiring intensive efforts through personal communication, meetings, advisory groups and social media. Accredited training programmes were effective incentives for participation from healthcare providers; and aligning research findings with competing policy priorities enabled interest and dialogue with decision-makers. The COVID-19 pandemic severely limited possibilities for planned engagement, although remote methods were used where possible. Planned and persistent engagement contributed to shared knowledge and commitment to change, including raised patient and public awareness about COPD, improved skills and practice of healthcare providers, increased interest and support from clinical leaders, and dialogue for integrating COPD services into national policy and practice. CONCLUSION: Stakeholder engagement enabled relevant local actors to produce and utilise knowledge for small wins such as improving day-to-day practice and for long-term goals of equitable access to COPD care. For it to be successful and sustained, stakeholder engagement needs to be valued and integrated throughout the research and knowledge generation process, complete with dedicated resources, contextualised and flexible planning, and commitment.

Rationale and design of REGULATE: an observational study protocol for relationship between plasma metabolome and the efficacy of systemic glucocorticoid in acute exacerbation of chronic obstructive pulmonary disease.

BACKGROUND: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) significantly increases the mortality of patients with COPD. Guidelines have recommended systemic glucocorticoid as a regular treatment. Recently, evidence has shown that systemic glucocorticoid cannot be a benefit to all of the patients with AECOPD. Thus, the problem that how the clinicians can screen the patients who can benefit from systemic glucocorticoid needs to be solved urgently. This study is aimed to detect the metabolic biomarkers and metabolic pathways that are related to the efficacy of systemic glucocorticoid and contribute to the precise treatment of COPD. METHODS AND DESIGN: In this study, we will utilize ultraperformance liquid chromatography/mass spectrometry (LC-MS) and gas chromatography/mass spectrometry (GC-MS) methods for the analysis of the metabolites in AECOPD patients and compare the metabolites profiles between patients with systemic glucocorticoid treatment success group and treatment failure group. We aim to detect the metabolic biomarkers and metabolic pathways that are related to the efficacy of systemic glucocorticoid and contribute to the precise treatment of COPD. DISCUSSION: Previous studies have found that plasma metabolome changed significantly after dexamethasone treatment in healthy participants. Furthermore, inter-person variability was high and remained uninfluenced by treatment, suggesting the potential of metabolomics for predicting the efficacy and side effects of systemic glucocorticoid. Therefore, we hypothesized that metabolome changes in patients with AECOPD may be associated with the efficacy of systemic glucocorticoid. Trial registration Clinicaltrials.gov registration number NCT04710849. Registered 15 January 2021, https://clinicaltrials.gov/ct2/show/NCT04710849 .

Interactions of fluoroquinolone antibiotics with sodium hypochlorite in bromide-containing synthetic water: Reaction kinetics and transformation pathways.

Seven popular fluoroquinolone antibiotics (FQs) in synthetic marine aquaculture water were subject to sodium hypochlorite (NaClO) disinfection scenario to investigate their reaction kinetics and transformation during chlorination. Reactivity of each FQ to NaClO was following the order of ofloxacin (OFL) > enrofloxacin (ENR) > lomefloxacin (LOM) > ciprofloxacin (CIP) ~ norfloxacin (NOR) >> pipemedic acid (PIP), while flumequine did not exhibit reactivity. The coexisting chlorine ions and sulfate ions in the water slightly facilitated the oxidation of FQs by NaClO, while humic acid was inhibitable to their degradation. The bromide ions promoted degradation of CIP and LOM, but restrained oxidation of OFL and ENR. By analysis of liquid chromatography with tandem mass spectrometry (LC-MS/MS), eight kinds of emerging brominated disinfection byproducts (Br-DBPs) caused by FQS were primarily identified in the chlorinated synthetic marine culture water. Through density functional theory calculation, the highest-occupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) characteristic as well as the charge distribution of the FQs were obtained to clarify transformation mechanisms. Their formation involved decarboxylation, ring-opening/closure, dealkylation and halogenation. Chlorine substitution occurred on the ortho-position of FQs's N4 and bromine substitution occurred on C8 position. The piperazine ring containing tertiary amine was comparatively stable, while this moiety with a secondary amine structure would break down during chlorination. Additionally, logKow and logBAF of transformation products were calculated by EPI-SuiteTM to analyze their bioaccumulation. The values indicated that Br-DBPs are easier to accumulate in the aquatic organism relative to their chloro-analogues and parent compounds.

Screening and early warning system for chronic obstructive pulmonary disease with obstructive sleep apnoea based on the medical Internet of Things in three levels of healthcare: protocol for a prospective, multicentre, observational cohort study.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnoea (OSA) are prevalent respiratory diseases in China and impose significant burdens on the healthcare system. Moreover, the co-occurrence of COPD and OSA exacerbates clinical outcomes significantly. However, comprehensive epidemiological investigations in China remain scarce, and the defining characteristics of the population affected by COPD and OSA, alongside their intrinsic relationship, remain ambiguous. METHODS AND ANALYSIS: We present a protocol for a prospective, multicentre, observational cohort study based on a digital health management platform across three different healthcare tiers in five sites among Chinese patients with COPD. The study aims to establish predicative models to identify OSA among patients with COPD and to predict the prognosis of overlap syndrome (OS) and acute exacerbations of COPD through the Internet of Things (IoT). Moreover, it aims to evaluate the feasibility, effectiveness and cost-effectiveness of IoT in managing chronic diseases within clinical settings. Participants will undergo baseline assessment, physical examination and nocturnal oxygen saturation measuring. Specific questionnaires screening for OSA will also be administered. Diagnostic lung function tests and polysomnography will be performed to confirm COPD and OSA, respectively. All patients will undergo scheduled follow-ups for 12 months to record the changes in symptoms, lung functions and quality of life. Primary outcomes include the prevalence and characteristics of OS, while secondary outcomes encompass OS prognosis and the feasibility of the management model in clinical contexts. A total of 682 patients with COPD will be recruited over 12-24 months. ETHICS AND DISSEMINATION: The study has been approved by Peking University Third Hospital, and all study participants will provide written informed consent. Study results will be published in an appropriate journal and presented at national and international conferences, as well as relevant social media and various stakeholder engagement activities. TRIAL REGISTRATION NUMBER: NCT04833725.

Allergic bronchopulmonary aspergillosis with marked peripheral blood eosinophilia and pulmonary eosinophilia: A case report.

BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) is an immune-related pulmonary disease caused by sensitization of airway by Aspergillus fumigatus. The disease manifests as bronchial asthma and recurring pulmonary shadows, which may be associated with bronchiectasis. The diagnosis of ABPA mainly depends on serological, immunological, and imaging findings. Pathological examination is not necessary but may be required in atypical cases to exclude pulmonary tuberculosis, tumor, and other diseases through lung biopsy. CASE SUMMARY: An 18-year-old man presented with recurrent wheezing, cough, and peripheral blood eosinophilia. Chest computed tomography showed pulmonary infiltration. There was a significant increase in eosinophils in bronchoalveolar lavage fluid. There was no history of residing in a parasite-endemic area or any evidence of parasitic infection. Pathologic examination of bronchoalveolar lavage fluid excluded fungal and mycobacterial infections. The patient was receiving medication for comorbid diseases, but there was no temporal correlation between medication use and clinical manifestations, which excluded drug-induced etiology. Histopathological examination of lung biopsy specimen showed no signs of eosinophilic granulomatosis with polyangiitis, IgG4-related diseases, or tumors. The diagnosis of ABPA was considered based on the history of asthma and the significant increase in serum Aspergillus fumigatus-specific immunoglobulin (Ig)E. Eosinophil-related diseases were excluded through pathological biopsy, which showed typical pathological manifestations of ABPA. CONCLUSION: The possibility of ABPA should be considered in patients with poorly controlled asthma, especially those with eosinophilia, lung infiltration shadows, or bronchiectasis. Screening for serum IgE, Aspergillus fumigatus-specific IgE and IgG, and alveolar lavage can help avoid misdiagnosis.

Severe/critical COVID-19 early warning system based on machine learning algorithms using novel imaging scores.

BACKGROUND: Early identification of severe/critical coronavirus disease 2019 (COVID-19) is crucial for timely treatment and intervention. Chest computed tomography (CT) score has been shown to be a significant factor in the diagnosis and treatment of pneumonia, however, there is currently a lack of effective early warning systems for severe/critical COVID-19 based on dynamic CT evolution. AIM: To develop a severe/critical COVID-19 prediction model using a combination of imaging scores, clinical features, and biomarker levels. METHODS: This study used an improved scoring system to extract and describe the chest CT characteristics of COVID-19 patients. The study also took into consideration the general clinical indicators such as dyspnea, oxygen saturation, alternative lengthening of telomeres (ALT), and androgen suppression treatment (AST), which are commonly associated with severe/critical COVID-19 cases. The study employed lasso regression to evaluate and rank the significance of different disease characteristics. RESULTS: The results showed that blood oxygen saturation, ALT, IL-6/IL-10, combined score, ground glass opacity score, age, crazy paving mode score, qsofa, AST, and overall lung involvement score were key factors in predicting severe/critical COVID-19 cases. The study established a COVID-19 severe/critical early warning system using various machine learning algorithms, including XGBClassifier, Logistic Regression, MLPClassifier, RandomForestClassifier, and AdaBoost Classifier. The study concluded that the prediction model based on the improved CT score and machine learning algorithms is a feasible method for early detection of severe/critical COVID-19 evolution. CONCLUSION: The findings of this study suggest that a prediction model based on improved CT scores and machine learning algorithms is effective in detecting the early warning signals of severe/critical COVID-19.

Association of multiple air pollutants with oxygen saturation during sleep in COPD patients: Effect modification by smoking status and airway inflammatory phenotypes.

Air pollution contributes substantially to the development of chronic obstructive pulmonary disease (COPD). To date, the effect of air pollution on oxygen saturation (SpO2) during sleep and potential susceptibility factors remain unknown. In this longitudinal panel study, real-time SpO2 was monitored in 132 COPD patients, with 270 nights (1615 h) of sleep SpO2 recorded. Exhaled nitric oxide (NO), hydrogen sulfide (H2S) and carbon monoxide (CO) were measured to assess airway inflammatory characteristics. Exposure levels of air pollutants were estimated by infiltration factor method. Generalized estimating equation was used to investigate the effect of air pollutants on sleep SpO2. Ozone, even at low levels (<60 µg/m3), was significantly associated with decreased SpO2 and extended time of oxygen desaturation (SpO2 < 90%), especially in the warm season. The associations of other pollutants with SpO2 were weak, but significant adverse effects of PM10 and SO2 were observed in the cold season. Notably, stronger effects of ozone were observed in current smokers. Consistently, smoking-related airway inflammation, characterized by higher levels of exhaled CO and H2S but lower NO, significantly augmented the effect of ozone on SpO2 during sleep. This study highlights the importance of ozone control in protecting sleep health in COPD patients.

An online survey of primary care physicians' knowledge of common respiratory diseases in China.

China has a huge population with respiratory diseases, these diseases should be managed well in primary care, however, primary care physicians' knowledge level of these diseases were unknown. The aim of the study was to assess primary care physicians' knowledge of asthma, CAP, COPD, and influenza in China. An e-questionnaire was distributed to attendees of respiratory diseases academic conferences in China from July, 2017 to December, 2018. 7391 questionnaires were returned and 4815 valid questionnaires were analyzed, 3802 (79.0%) from community health service centers and 1013 (21.0%) from township hospitals. The average score of the questionnaire was 83.3 (±20.397) and 72.1 (±20.898) in township and community hospitals, respectively (P < 0.05). 61.4%, 48.7%, and 42.5% of the primary care physicians were aware of clinical manifestations of COPD, asthma, and simple influenza. 85.7%, 8.1%, 16.1%, and 1.0% knew how to diagnose COPD, asthma, CAP and influenza, respectively. 94.4% of the physicians lacked the knowledge of treating COPD with bronchodilators; 53.7% knew non-pharmacological treatments for COPD. 73.6% were unable to deal with asthma attacks. 65.1% did not know what the most essential and important treatment for influenza was. 92% of physicians did not know the management for stable COPD; 3.0% knew all prevention and management measures for asthma. 37.9% knew all the preventive measures for CAP. 44.9% did not know the important role of influenza vaccine in preventing influenza and its complications. Primary care physicians in China had a poor knowledge of CAP, asthma, Influenza, COPD. There is a need for improved training of common respiratory diseases.

Variations in the life-cycle parameters and population growth of rotifer Brachionus plicatilis under the stress of microplastics and 17ß-estradiol.

The toxic effects of microplastics (MPs) on biota are related to their particle size. In addition, MPs could adsorb ambient pollutants in water, which increase the threat of MPs to organisms. In this study, the effects of different particle sizes and concentrations of MPs on the life-cycle parameters and population growth of rotifer Brachionus plicatilis were investigated, and the combined effects of MPs and 17ß-estradiol (E2) on rotifers were studied. Results showed small particle size (50 nm) MPs had negative effects on the lifespan, time to first batch of eggs, fecundity, and population growth rate of rotifers, which were dose-dependent, but large (100 nm and 500 nm) MPs were not. In addition, both life-cycle parameters and the population growth of rotifers were not affected by E2. However, the combination effects of different particle sizes of MPs and E2 on the lifespan, reproductive period, offspring per female, and population growth of rotifers were significant. Therefore, rotifers were more vulnerable to smaller particle MPs, and the coexistence of MPs and other environmental pollutants posed a serious threat to rotifers.

Hydrogen sulfide alleviates particulate matter-induced emphysema and airway inflammation by suppressing ferroptosis.

BACKGROUND: Redox imbalance is an vital mechanism for COPD. At present, insufficient researches have been conducted on the protective effect of hydrogen sulfide (H2S) on PM-induced COPD. However, whether H2S exerts the anti-injury role by blocking ferroptosis and restoring redox equilibrium remain to be investigated. METHODS: Human lung tissue samples were collected for IHC staining, and the expressions of Nrf2, ferritinophagy- and ferroptosis-related proteins were observed. The WT C57BL/6 and Nrf2 knockout mice models were established with PM(200 µg per mouse). NaHS(Exogenous H2S) was injected intraperitoneally 30 min in advance. Twenty-nine days later, mice lung tissues were evaluated by HE's and PERLS-DAB's staining. Meanwhile, inflammation and oxidative stress indicators and iron levels were assessed by corresponding ELISA kit. Related protein expressions were detected through Western blot. BEAS-2B cells with or without H2S were exposed to PM2.5 for 36 h. Cell viability, mitochondrial morphology, inflammatory cytokines, antioxidant factors, iron levels, autophagic flux and the levels of ROS, LIP ROS, MitoROS, MMP, as well as related protein expressions were detected by specific methods, respectively. In addition, V5-Nrf2, Nrf2 siRNA, Nrf2 inhibitor ML385, PPAR-γ inhibitor GW9662, autophagy inhibitor CQ, iron chelator DFO and ferroptosis inhibitor Fer-1 were used to verify the target signaling pathways. RESULTS: We found that the expressions of LIP ROS, ROS, COX2, MDA and other oxidative factors increased, while the antioxidant markers GPX4, GSH and GSH-Px significantly decreased, as well as active iron accumulation in COPD patients, PM-exposured WT and Nrf2-KO mice models and PM2.5-mediated cell models. NaHS pretreatment markedly inhibited PM-induced emphysema and airway inflammation by alleviating ferroptotic changes in vivo and vitro. With the use of V5-Nrf2 overexpression plasmid, Nrf2 siRNA and pathway inhibitors, we found NaHS activates the expressions of Nrf2 and PPAR-γ, and inhibites ferritinophagy makers LC3B, NCOA4 and FTH1 in BEAS-2B cells. Moreover, the anti-ferroptotic effect of NaHS was further verified to be related to the activation of Nrf2 signal in MEF cells. CONCLUSION: This research suggested that H2S alleviated PM-induced emphysema and airway inflammation via restoring redox balance and inhibiting ferroptosis through regulating Nrf2-PPAR-ferritinophagy signaling pathway.

Community lung health service design for COPD patients in China by the Breathe Well group.

COPD is increasingly common in China but is poorly understood by patients, medications are not used as prescribed and there is no access to recommended non-pharmacological treatment. We explored COPD patients' and general practitioners' (GPs) knowledge of COPD, views on its management and the acceptability of a flexible lung health service (LHS) offering health education, exercise, self-management, smoking cessation and mental health support. Using a convergent mixed methods design, data were collected from patients and GPs using focus groups (FGs) in four Chinese cities, questionnaires were also used to collect data from patients. FGs were audio-recorded and transcribed. Quantitative data were analysed descriptively, thematic framework analysis was used for the qualitative data. Two-hundred fifty-one patients completed the questionnaire; 39 patients and 30 GPs participated in ten separate FGs. Three overarching themes were identified: patients' lack of knowledge/understanding of COPD, current management of COPD not meeting patients' needs and LHS design, which was well received by patients and GPs. Participants wanted COPD education, TaiChi, psychological support and WeChat for social support. 39% of survey responders did not know what to do when their breathing worsened and 24% did not know how to use their inhalers. 36% of survey respondents requested guided relaxation. Overall, participants did not fully understand the implications of COPD and current treatment was sub-optimal. There was support for developing a culturally appropriate intervention meeting Chinese patients' needs, health beliefs, and local healthcare delivery. Further research should explore the feasibility of such a service.

Toxicity of disinfection byproducts formed during the chlorination of sulfamethoxazole, norfloxacin, and 17ß-estradiol in the presence of bromide.

Brominated disinfection byproducts (Br-DBPs) are formed during the disinfection process of water containing bromine ions, such as marine aquaculture water. Little attention has been paid to Br-DBPs with anthropogenic chemicals as precursors. This study summarized the sodium hypochlorite (NaClO) oxidation of three frequently used pharmaceuticals, including two antibiotics, norfloxacin (NOR) and sulfamethoxazole (SMX), and the growth hormone estrogen 17ß-estradiol (E2). Transformations of the pharmaceuticals were found to be faster in marine aquaculture water than in distilled water. Several Br-DBPs and Cl-DBPs were identified for NOR, SMX, and E2. It was shown that the carboxyl group, piperazine ring, C3, and C8 atoms were the primary reaction sites on NOR. The aniline moiety and S-N bond were identified to be the reaction sites on SMX. The C2, C4, C9, and C16 atoms were the potential reaction centers on E2. Preliminary calculation by QSAR model indicated that the value of logKow significantly increased with an increase in the number of bromine atoms in the Br-DBPs. The results of the bioconcentration factors (BCF) analysis suggested that the bioaccumulation of Br-DBPs were greater than that chlorinated DBPs (Cl-DBPs) in distilled water.

Perspectives of research ethics committee members on human challenge studies in the development of vaccines against COVID-19: a mixed methods study.

BACKGROUND: Vaccines are considered the most effective protection against the coronavirus disease 2019 (COVID-19). Human Challenge Studies can help to shorten the development process of vaccines. The reviewers' opinions from research ethics committees (REC) play an essential gate-keeping role in determining whether a clinical trial can be conducted or not. METHODS: A convergent mixed-methods study was conducted in a leading general hospital in China. A total of 58 REC members from the institution were invited to participate in an online questionnaire survey. According to the result of the quantitative survey, 15 of these REC members were purposefully selected to participate in qualitative interviews further. Quantitative data were analyzed using descriptive statistical techniques, and thematic analysis was used to analyze the qualitative data. Findings from the quantitative and qualitative analyses were synthesized to deeply illustrate the attitudes, views, and suggestions of REC members on human challenge studies to develop COVID-19 vaccination. RESULTS: The response rate of the online questionnaire was 62% (36/58), and 15 of the respondents were interviewed. All participants deemed that the human challenge study should provide compensation to its participants and that sufficiently informed consent is necessary. The human challenge study was disagreed with by 38.9% of participants. The key points of concern raised were representativeness and fairness of participant selection, benefit, and risk, vulnerable groups, compensation to participants, informed consent, and general view on human challenge studies. CONCLUSIONS: Human challenge studies helped accelerate the development of vaccines for disease control to a certain extent, but the bottom line of medical ethics should not have been broken. At any time, the rights and interests of research participants should come first.

Accuracy and cost-effectiveness of different screening strategies for identifying undiagnosed COPD among primary care patients (≥40 years) in China: a cross-sectional screening test accuracy study: findings from the Breathe Well group.

OBJECTIVES: To examine the accuracy and cost-effectiveness of various chronic obstructive pulmonary disease (COPD) screening tests and combinations within a Chinese primary care population. DESIGN: Screening test accuracy study. SETTING: Urban and rural community health centres in four municipalities of China: Beijing (north), Chengdu (southwest), Guangzhou (south) and Shenyang (northeast). PARTICIPANTS: Community residents aged 40 years and above who attended community health centres for any reason were invited to participate. 2445 participants (mean age 59.8 (SD 9.6) years, 39.1% (n=956) male) completed the study (February-December 2019), 68.9% (n=1684) were never-smokers and 3.6% (n=88) had an existing COPD diagnosis. 13.7% (n=333) of participants had spirometry-confirmed airflow obstruction. INTERVENTIONS: Participants completed six index tests (screening questionnaires (COPD Diagnostic Questionnaire, COPD Assessment in Primary Care To Identify Undiagnosed Respiratory Disease and Exacerbation Risk (CAPTURE), Chinese Symptom-Based Questionnaire (C-SBQ), COPD-SQ), microspirometry (COPD-6), peak flow (model of peak flow meters used in the study (USPE)) and the reference test (ndd Easy On-PC). PRIMARY AND SECONDARY OUTCOMES: Cases were defined as those with forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) below the lower limit of normal (LLN-GLI) on the reference test. Performance of individual screening tests and their combinations was evaluated, with cost-effectiveness analyses providing cost per additional true case detected. RESULTS: Airflow measurement devices (sensitivities 64.9% (95% CI 59.5% to 70.0%) and 67.3% (95% CI 61.9% to 72.3%), specificities 89.7% (95% CI 88.4% to 91.0%) and 82.6% (95% CI 80.9% to 84.2%) for microspirometry and peak flow, respectively) generally performed better than questionnaires, the most accurate of which was C-SBQ (sensitivity 63.1% (95% CI 57.6% to 68.3%) specificity 74.2% (95% CI 72.3% to 76.1%)). The combination of C-SBQ and microspirometry used in parallel maximised sensitivity (81.4%) (95% CI 76.8% to 85.4%) and had specificity of 68.0% (95% CI 66.0% to 70.0%), with an incremental cost-effectiveness ratio of £64.20 (CNY385) per additional case detected compared with peak flow. CONCLUSIONS: Simple screening tests to identify undiagnosed COPD within the primary care setting in China is possible, and a combination of C-SBQ and microspirometry is the most sensitive and cost-effective. Further work is required to explore optimal cut-points and effectiveness of programme implementation. TRIAL REGISTRATION NUMBER: ISRCTN13357135.

Ultraviolet/peroxydisulfate degradation of ofloxacin in seawater: Kinetics, mechanism and toxicity of products.

The ultraviolet/peroxydisulfate (UV/PDS) system was used to degrade ofloxacin (OFL) in fresh water, synthetic marine aquaculture water and synthetic seawater. The comparison of the reaction degradation rate constants proved that the order of reaction rate was the following: synthetic seawater (0.77 min-1) > synthetic marine aquaculture water (0.74 min-1) > freshwater (0.30 min-1). Bromide (Br-) and bicarbonate (HCO3-) promote the degradation of OFL, whereas chloride (Cl-) inhibits the degradation. The piperazine ring of OFL was the main reactive group, and atoms N1, C6, C7 and N2 were identified as the reaction sites. Based on the intermediate and final products, the possible degradation pathways of OFL in the three kinds of water were proposed. Additionally, during the UV/PDS treatment of synthetic marine aquaculture water containing Cl- and Br-, the oxidation products of OFL showed a slight toxicity to Chlorella pyrenoidosa (C. pyrenoidosa) and Priacanthus tayenus (P. tayenus). The maximum growth inhibition rate of the products to C. pyrenoidosa was 9.72%. The products also caused liver cells of P. tayenus to be damaged and reduced the species richness and diversity of intestinal microorganism. Nevertheless, compared with the products degraded by traditional disinfection methods using NaClO, the biological toxicities were much lower. UV/PDS can be used for seawater as a new alternative disinfection method.

Study to evaluate the effectiveness and cost-effectiveness of different screening strategies for identifying undiagnosed COPD among residents (≥40 years) in four cities in China: protocol for a multicentre cross-sectional study on behalf of the Breathe Well group.

INTRODUCTION: The latest chronic obstructive pulmonary disease (COPD) epidemiology survey in China estimated that there were 99 million potential COPD patients in the country, the majority of whom are undiagnosed. Screening for COPD in primary care settings is of vital importance for China, but it is not known which strategy would be the most suitable for adoption in primary care. Studies have been conducted to test the accuracy of questionnaires, expiratory peak flow meters and microspirometers to screen for COPD, but no study has directly evaluated and compared the effectiveness and cost-effectiveness of these methods in the Chinese setting. METHODS AND ANALYSIS: We present the protocol for a multicentre cross-sectional study, to be conducted in eight community hospitals from four cities among Chinese adults aged 40 years or older to investigate the effectiveness and cost-effectiveness of different case-finding methods for COPD, and determine the test performance of individual and combinations of screening tests and strategies in comparison with quality diagnostic spirometry. Index tests are screening questionnaires (COPD Diagnostic Questionnaire (CDQ), COPD Assessment in Primary Care To Identify Undiagnosed Respiratory Disease and Exacerbation Risk Questionnaire (CAPTURE), symptom-based questionnaire, COPD Screening Questionnaire (COPD-SQ)), microspirometer and peak flow. Each participant will complete all of these tests in one assessment. The primary analysis will compare the performance of a screening questionnaire with a handheld device. Secondary analyses will include the comparative performance of each index test, as well as a comparison of strategies where we use a screening questionnaire and a handheld device. Approximately 2000 participants will be recruited over 9 to 12 months. ETHICS AND DISSEMINATION: The study has been approved by Peking University Hospital and University of Birmingham. All study participants will provide written informed consent. Study results will be published in appropriate journal and presented at national and international conferences, as well as relevant social media and various community/stakeholder engagement activities. TRIAL REGISTRATION NUMBER: ISRCTN13357135.

An Efficient and Perceptually Motivated Auditory Neural Encoding and Decoding Algorithm for Spiking Neural Networks.

The auditory front-end is an integral part of a spiking neural network (SNN) when performing auditory cognitive tasks. It encodes the temporal dynamic stimulus, such as speech and audio, into an efficient, effective and reconstructable spike pattern to facilitate the subsequent processing. However, most of the auditory front-ends in current studies have not made use of recent findings in psychoacoustics and physiology concerning human listening. In this paper, we propose a neural encoding and decoding scheme that is optimized for audio processing. The neural encoding scheme, that we call Biologically plausible Auditory Encoding (BAE), emulates the functions of the perceptual components of the human auditory system, that include the cochlear filter bank, the inner hair cells, auditory masking effects from psychoacoustic models, and the spike neural encoding by the auditory nerve. We evaluate the perceptual quality of the BAE scheme using PESQ; the performance of the BAE based on sound classification and speech recognition experiments. Finally, we also built and published two spike-version of speech datasets: the Spike-TIDIGITS and the Spike-TIMIT, for researchers to use and benchmarking of future SNN research.

Transformation of norfloxacin during the chlorination of marine culture water in the presence of iodide ions.

The antibacterial agent norfloxacin (NOR) and sodium hypochlorite (NaClO), which are both widely used in marine culture, react with each other to form the halogenated disinfection byproducts (X-DBPs). The effects of the water characteristics and iodide concentration on the reaction kinetics were investigated. The results showed that the reaction rate of NOR with NaClO increases from 0.0586 min-1 to 0.1075 min-1 when the iodide concentration was changed from 0 µg-1 to 50 µg-1. This demonstrated the enhancement of NOR oxidation in the presence of iodide ions. Four novel iodinated DBPs (I-DBPs) were identified in the marine culture water. Iodine substitutions occurred at the C3 and C8 positions of NOR. The formation mechanisms of X-DBPs in the marine culture water were proposed based on the intermediate and final products. NOR may undergo a ring-opening reaction, a de-carbonyl reaction and substitution to form intermediates and finally generate the X-DBPs. Furthermore, the predicted logKOW and logBCF values of the I-DBPs were higher than that of the Br-DBPs and Cl-DBPs. The AOX concentration in the synthetic water samples decreased in the following order: seawater (8.49 mg L-1) > marine culture water (4.05 mg L-1) > fresh water (1.89 mg L-1). The amount of AOX also increased with the increase in iodide concentration. These results indicated that the I-DBPs were more toxic than their brominated and chlorinated analogues.

17ß-estradiol as precursors of Cl/Br-DBPs in the disinfection process of different water samples.

During chlorine disinfection process, reactions between the disinfectant and 17ß-estradiol (E2) lead to the formation of halogenated disinfection byproducts (DBPs) which can be a risk to both ecosystem and human health. The degradation and transformation products of E2 in sodium hypochlorite (NaClO) disinfection processes of different water samples were investigated. The reaction kinetics research showed that the degradation rates of E2 were considerably dependent on the initial pH value and the types of water samples. In fresh water, synthetic marine aquaculture water and seawater, the reaction rate constant was 0.133 min-1, 2.067 min-1 and 2.592 min-1, respectively. The reasons for the above phenomena may be due to the different concentrations of bromide ions (Br-) in these three water samples which could promote the reaction between NaClO and E2. Furthermore, Br- could also cause the formation of brominated DBPs (Br-DBPs). The main DBPs, reaction centers and conceivable reaction pathways were explored. Seven halogenated DBPs have been observed including three chlorinated DBPs (Cl-DBPs) and four Br-DBPs. The active sites of E2 were found to be the pentabasic cyclic ring and the ortho position of the phenol moiety as well as C9-C10 position. The identified Cl/Br-DBPs were also confirmed in actual marine aquaculture water from a shrimp pond. The comparison of bio-concentration factors (BCF) values based on calculation of EPI-suite showed that the toxicities of the Br-DBPs were stronger than that of their chloride analogues. The absorbable organic halogens (AOX) analysis also suggested that the DBPs produced in the marine aquaculture water were more toxic than that in the fresh water system.