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Background: In the last decades, the molecular epidemiological investigation of Mycobacterium tuberculosis has significantly increased our understanding of tuberculosis epidemiology. However, few such studies have been done in southern Xinjiang, China. We aimed to clarify the molecular epidemic characteristics and their association with drug resistance in the M. tuberculosis isolates circulating in this area. Methods: A total of 347 isolates obtained from southern Xinjiang, China between Sep, 2017 and Sep, 2019 were included to characterize using a 15-locus MIRU-VNTR (VNTR-15China) typing and spoligotyping, and test for drug susceptibility profiles. Then the lineages and clustering of the isolates were analyzed, as well as their association with drug resistance. Results: Spoligotyping results showed that 60 spoligotype international types (SITs) containing 35 predefined SITs and 25 Orphan or New patterns, and 12 definite genotypes were found, and the top three prevalent genotypes were Beijing genotype (207, 59.7%), followed by CAS1-Delhi (46, 13.6%), and Ural-2 (30, 8.6%). The prevalence of Beijing genotype infection in the younger age group (≤ 30) was more frequent than the two older groups (30~59 and ≥ 60 years old, both P values < 0.05). The Beijing genotype showed significantly higher prevalence of resistance to isoniazid, rifampicin, ethambutol, multi-drug or at least one drug than the non-Beijing genotype (All P values ≤ 0.05). The estimated proportion of tuberculosis cases due to transmission was 18.4% according to the cluster rate acquired by VNTR-15China typing, and the Beijing genotype was the risk factor for the clustering (OR 9.15, 95% CI: 4.18– 20.05). Conclusion: Our data demonstrated that the Beijing genotype is the dominant lineage, associated with drug resistance, and was more likely to infect young people and contributed to tuberculosis transmission in southern Xinjiang, China. These findings will contribute to a better understanding of tuberculosis epidemiology in this area. [ABSTRACT FROM AUTHOR]

Background: The diagnosis and treatment of patients with bronchiectasis and nontuberculous mycobacterium (NTM) pulmonary disease are challenging issues and the treatment is also prolonged and depends on the species. There is limited information on patients with bronchiectasis and NTM pulmonary disease in Mainland China.Methods: This cross-sectional study was conducted at the China-Japan Friendship Hospital, Beijing, China. Those adult patients who met the diagnostic criteria for bronchiectasis and obtained a culture result of mycobacteria from lower respiratory tract specimens or lung tissue were included in this study. A logistic regression model was used to identify the related factors in patients with NTM pulmonary disease.Results: A total of 202 patients with bronchiectasis from 19 cities, 155 without and 47 (23.3%) with NTM pulmonary disease, were included. In all the 47 patients with NTM pulmonary disease, Mycobacterium avium complex was the most common species (66.0%), and 72.3% of them were initiated on standard anti-NTM treatment within 3 months after the diagnosis of NTM pulmonary disease. A larger proportion of patients with NTM pulmonary disease had acute exacerbations of ≥ 3 times within 1 year and were diagnosed bronchiectasis ≥ 50 years among patients with NTM pulmonary disease. The HRCT chest images revealed higher proportions of nodular shadow (100% vs. 35.3%), tree-in-bud sign (97.9% vs. 29.0%), cavities (29.8% vs. 5.8%), and airway dilation of the right middle lobe or the left lingular lobe (63.8% vs. 23.9%) in patients with NTM pulmonary disease than in those without NTM pulmonary disease (all P values = 0.001). The multivariable logistic regression model indicated that three and more abnormal features (OR 33.8; 95% CI 11.1-102.8) and main lesions of bronchial expansion in the middle or lingual lobe (OR 6.4; 95% CI 2.4-16.6) in HRCT chest images were independently associated with NTM pulmonary disease (P values = 0.001).Conclusion: In a single center of Mainland China, > 23% of patients with bronchiectasis had NTM pulmonary disease, and most patients were started on standard treatment within 3 months after the diagnosis of NTM pulmonary disease. These findings suggest that patients with bronchiectasis should be thoroughly examined for the presence of NTM pulmonary disease.Trial Registration: NCT03594032. [ABSTRACT FROM AUTHOR]

Introduction: The long‐term mortality rate in adolescent and middle‐aged patients with low‐medium risk community‐acquired pneumonia (CAP) remains unelucidated. Objective: Understanding the long‐term mortality rate in adolescent and middle‐aged patients with low‐medium risk CAP in Beijing, China, to provide a basis for the long‐term management of CAP patient. Methods: A follow‐up survey was conducted telephonically from December 2017 to January 2018 to assess the survival status among 808 patients from a CAP‐China cohort enrolled from 10 general hospitals in Beijing between November 2010 and April 2012. The all‐cause mortality rate was determined and Cox's proportional hazard model was performed to identify potential factors predicting mortality. Results: Among the 808 patients, the mean age (SD) was 45.4 (19.6) year‐old and the median (IQR) pneumonia severity index (PSI) score was 42.0 (35.8). Survival status for a total of 426 (52.7%) were determined during the follow‐up and the non‐follow‐up patients were with slightly larger PSI score. The mean age (SD) for the follow‐up patients were 44.6 (18.7) year‐old and the median (IQR) PSI score was 42.0 (33.3). Over a median of 7 years, 32 participants died and the cumulative 1‐, 3‐, 5‐ and 7‐year all‐cause mortality rates were 1.6%, 4.2%, 5.9% and 7.5%, respectively. The average annual standardized mortality rate among the study participants was 9.79‰, which was significantly higher than the mortality rate of 5.20‰ among Beijing residents in 2016. Multivariable Cox proportional hazards analyses revealed that age, comorbidity and PSI were independent prognostic factors associated with long‐term mortality, with hazard ratios of 4.953 (95% confidence interval [CI]3.270‐7.502), 2.393 (95% CI 1.148‐4.985) and 3.553 (95% CI 2.607‐4.843), respectively. [Correction added on 20 August 2020, after first online publication: "9.79%" has been corrected to "9.79‰".] Conclusion: The long‐term mortality rate is higher among patients with CAP compared with the age‐adjusted general population in the same city. Age, comorbidity and initial PSI class are independently prognostic factors for the long‐term mortality rate. [ABSTRACT FROM AUTHOR]

Background : Respiratory syncytial virus (RSV) is an important cause of medically attended acute respiratory illnesses in older adults but awareness of the relevance of RSV in older people remains lower than that of influenza, which exhibits similar clinical characteristics to those of RSV. Objectives: This study was performed to assess the clinical significance of RSV in respiratory samples from hospitalized adults. Methods: Characteristics and outcomes in adults (≥18 years) hospitalized for RSV infection (n = 51) were compared with a cohort hospitalized for influenza A infection (n = 279) in a single‐center retrospective cohort study in Beijing, China. Results: Respiratory syncytial virus patients were slightly older, with no significant differences in underlying chronic conditions. Lower respiratory tract infection and cardiovascular complications were more frequent (P <.05) in RSV patients. Rates of mortality in the RSV cohorts were significantly higher within 30 days (13.7% vs 5.0%, P =.019) and 60 days (17.6% vs 7.5%, P =.021). Bacterial co‐infection in respiratory samples was associated with reduced survival among RSV patients (log rank, P =.013). Conclusions: Respiratory syncytial virus is a common cause of serious illness among hospitalized adults in China with greater mortality than influenza A. Increased awareness and the availability of antiviral agents might increase the scope for successful management. [ABSTRACT FROM AUTHOR]

Multidrug resistance represents a growing threat to human beings, and alternative antimicrobial regimens to conventional antibiotic paradigms are being extensively searched to fight against multidrug-resistant bacteria (MDRB). Although the antimicrobial potency of silver nanomaterials (AgNMs) has been previously elaborated, their efficacy against MDRB still remains to be strengthened. Here, our data revealed that small-sized silver nanoclusters (AgNCs) are superior to conventional silver nanoparticles (AgNPs) as robust antimicrobials against multidrug-resistant (MDR) Pseudomonas aeruginosa (P. aeruginosa). The core structure and surface ligands of AgNCs are crucial for the outstanding antibacterial activity of AgNCs. On the one hand, due to the presence of amphiphilic ligands, AgNCs are relatively prone to associate with the cell membrane and partake in endocytosis with targeted bacterial cells. Molecular dynamics simulations also corroborated this finding. On the other hand, the nanocluster structure of AgNCs led to strong peroxidase-like activity associated with massive production of reactive oxygen species (ROS), which contributes to their overall bactericidal potency. These outstanding features of AgNCs result in elevated bacterial killing efficacy by impairing the cell wall/membrane, promoting oxidative stress and attenuating pivotal cellular processes, e.g., ATP synthesis. Notably, AgNCs manifested great efficacy in treating P. aeruginosa-generated pneumonia in mice and increased the survival of infected animals, as well as exhibited excellent biocompatibility. Taken together, the results of this study pinpoint the great promise of AgNCs as new alternative therapeutics against MDR P. aeruginosa. Biomaterials: A silver bullet against drug-resistant bacteria A silver nanomaterial that can destroy drug-resistant bacteria has been developed by researchers in China. The rise of antibiotic-resistant bacteria is a major source of concern in global health. Silver has long been known to have antibacterial properties, and so scientists are returning to it as a possible agent to combat these multidrug-resistant bacteria. While silver nanoparticles have previously been shown to have good antibacterial activity, a team led by Nanfeng Zheng, Xiamen University, and Sijin Liu, Chinese Academy of Sciences, Beijing, have shown that small clusters of silver particles are even better. The researchers determined the optimal size, structure and surface properties of antibacterial nanosilver clusters. They used their nanoclusters to treat pneumonia in mice caused by the multidrug-resistant bacteria Pseudomonas aeruginosa, increasing their survival rates. Our findings unearth the great importance of the size, core structure, and surface ligands in dictating the antibacterial activity of silver nanoclusters (AgNCs). Owing to the presence of amphiphilic ligands, AgNCs are more prone to adsorb the membrane and following endocytosis towards targeted bacterial cells, associated with membrane damage, as reflected by reinforced release of malondialdehyde (MDA). AgNCs bear strong peroxidase-like activity, coupled to massive production of reactive oxygen species (ROS). Altogether, these outstanding features of AgNCs resultantly elevated the bacteria-killing efficacy through impairing cell wall/membrane, promoting oxidative stress and attenuating pivotal cellular processes, e.g., ATP synthesis. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To establish and evaluate a real-time PCR assay to detect Mycoplasma pneumoniae (M.pneumoniae) in clinical specimens. Methods: By analysing the whole p1 gene sequence of 60 M.pneumoniae clinical isolates in Beijing of China, an optimized real-time PCR assay (MpP1) using p1 gene conserved region was designed. The specificity and sensitivity of this assay were evaluated and compared with other two reported assays (RepMp1 and Mp181) using 40 positive and 100 negative clinical specimens. Results: The detection limit of the new assay was 8.1 fg (about 1∼3CFU) M.pneumoniae DNA. The sensitivity of MpP1, RepMp1, and Mp181 assays appeared to be 100%, 100%, and 85%, respectively. Conclusion: MpP1 assay is suitable for the detection of M.pneumoniae in Chinese clinical specimens. [Copyright &y& Elsevier]

Abstract: Indoor environment quality is simultaneously determined by thermal, acoustic, and luminous environments and air quality. This paper reports the findings of field studies conducted in public buildings in Beijing and Shanghai in 2008 and 2009. The studies included measurements of indoor environmental parameters such as air temperature, mean radiant temperature, relative humidity, air velocity, CO2 concentration, illumination intensity, and A-weighted sound pressure levels, as well as investigations of the occupants’ satisfaction with these indoor environments. A predictive model for evaluating overall satisfaction with the indoor environment was developed based on the analysis of the relationship between occupants’ satisfaction and the different environmental parameters. This model can provide a valuable reference for building designers as they compare different schemes by helping them choose designs favored by most people. [Copyright &y& Elsevier]

Abstract: This study was conducted during the summer and winter in Beijing. Classrooms and offices in a university were used to conduct the survey. The respondents’ thermal sensation and thermal adaptability in both seasons were analyzed. During the study, indoor environmental parameters including air temperature, mean radiant temperature, relative humidity, and air velocity were measured. The respondents’ thermal sensation was determined by questionnaire. A relationship between indoor temperature and thermal sensation was found. In the summer study, the “scissors difference” between TSV and PMV was observed in the air-conditioned environments if the temperature was out of the neutral zone. People had higher tolerance in the hot environment than PMV predicted. During winter, the outdoor temperature had a prominent influence on thermal adaptability. The low outdoor temperature made people adapt to the cold environment. When the indoor temperature was heated to a high temperature by space heating facilities, respondents felt uncomfortable since their adaptability to the cold environment was nullified. Furthermore, the differences in thermal responses between respondents from North and South China showed that the different climates of people''s native regions also affected their thermal comfort and adaptability. [Copyright &y& Elsevier]

Abstract: VanB phenotype–vanA genotype vancomycin-resistant Enterococcus faecium (VREF) has never been reported in mainland China. We investigated the frequency and molecular characteristics of this strain in a Beijing tertiary hospital. Of 23 vanA genotype VREF clinical isolates, 12 (54.3%) were VanB phenotype–vanA genotype. Mutilocus sequence typing (MLST) analysis revealed that all isolates belong to a single clonal complex (CC78), which has been disseminated worldwide. Based on MLST and pulsed-field gel electrophoresis, 23 isolates were polyclonal dissemination in our hospital. Tn1546-like element structure analysis showed that of 12 VanB phenotype–vanA genotype isolates, 5 had complete deletion of vanY and vanZ accompanying insertion of IS1216V in vanX–vanY intergenic region, 5 had ISEfa4 insertion in orf2–vanR intergenic region, a new Tn1546 structure type, and 2 were identical to VanA phenotype–vanA genotype VREF. Data showed that the deletion of vanY and vanZ genes or ISEfa4 insertion in orf2–vanR intergenic region can partly explain the causes of difference between phenotype and genotype. [Copyright &y& Elsevier]

Mixed-mode (MM) buildings, integrating a naturally ventilated (NV) mode and an air-conditioned (AC) mode, have gained popularity in recent years. However, there is no consensus among previous studies on how to evaluate the thermal comfort of occupants of MM buildings. This study aims to compare the applicability of the PMV-PPD model and the adaptive model in MM buildings and to verify whether the occupants' thermal perception varies with different operating modes. A field study was conducted in an MM office building in Tianjin, China from March 2019 to January 2020, covering four seasons. Through a statistical analysis of environmental parameters and occupants' thermal responses, the difference in the thermal perception of occupants was observed between the two modes. The actual neutral T op (24.5 °C) was higher than the prediction calculated by PMV (23.0 °C). When the indoor T op was within the 80% acceptability limit of the adaptive model in ASHRAE Standard 55, over 80% of the occupants found the thermal environment acceptable in both AC-cooling mode and NV mode. The results revealed that the PMV-PPD model was not suitable for MM buildings, and the adaptive model showed better applicability in both AC-cooling mode and NV mode. Compared with the Beijing case in ASHRAE Global Thermal Comfort Database Ⅱ, the occupants in the current study had a higher neutral SET (24.3 °C) and better adaptability to the thermal environment. This study also showed that well-designed MM buildings were potentially applicable in mid-latitude temperate regions with four distinct seasons. • Occupants' thermal perception was affected by operating mode. • The PMV-PPD did not accurately predict the occupants' thermal sensations. • The adaptive model had better applicability in both AC-cooling mode and NV mode. • The neutral T op was 24.5 °C, and the neutral SET was 24.3 °C. • MM buildings are potentially applicable in regions with four distinct seasons. [ABSTRACT FROM AUTHOR]

• Seasonal variation of thermal environments and thermal comfort evaluations of the older households was observed through a yearlong continuous investigation. • The effect of outdoor temperature on window opening behavior and split air conditioner use and the effect of indoor temperature on clothing behavior were described. • Personal characteristics of older people influenced the preference for different adjustment methods. • The differences in behavioral adaptation between older and non-older people and between older people in different climate zones were discussed. Aged population is growing rapidly and aging in place is the major endowment pattern for older people. This study focused on the thermal living environments and thermal comfort of older people in their own homes. Special attention was paid to their behavioral adjustment characteristics. The longitudinal investigation was conducted from March 2018 to March 2019 in a residential community in Beijing, China, and the participants involved 5 households with 10 older respondents. The investigation included a yearlong continuous environmental measurement, behavioral monitoring, and a monthly collection of subjective evaluations. Face-to-face interviews on behavioral adjustments were also conducted with 102 older respondents in different communities in Beijing. The field investigation involved the observation of seasonal variation in the indoor environments and subjective evaluations. The prediction accuracy of the predicted mean vote (PMV) model was found to be inconsistent for thermal sensations of older people between the cold side and hot side. With regard to the behavioral adjustments of older people, this study described the effect of the outdoor temperature on window opening behavior and air conditioner use, and the effect of indoor temperature on clothing behavior. The preference for the adjustment methods were studied, and the personal characteristics of older people (including sex, age, educational background, and time spent at home) were found to influence their preference for different methods. The differences in behavioral adjustments between older and non-older people and between older people in different climate zones were discussed by comparing this study to previous field studies. [ABSTRACT FROM AUTHOR]

Summary: Objectives: An outbreak of bacteremia caused by Pseudomonas spp (P. fulva and P. putida) was first identified in our hospital in the summer of 2010 and reoccurred in the following year. Based on the epidemiological data collected in these 2 years, we initiated an investigation on the source of the outbreak. The aim of this study was to report the results of the investigation, as well as the intervention strategies that resulted in successful control of the outbreak. Methods: An infection control team was set up consisting of infectious disease specialists, microbiologists, infection control practitioners, and head nurses. The microbiology and medical records of case-patients with P. fulva or P. putida bloodstream infections were reviewed. Environmental samples and intravenous (IV) solutions from the wards and the pharmacy center were collected for culturing. The molecular characteristics of the bacterial isolates were studied by pulsed-field gel electrophoresis (PFGE). Strict infection control strategies were implemented. Results: A total of 20 case-patients from five inpatient wards were identified during three summer seasons from 2010 to 2012. Nineteen of them recovered with proper antibiotics. Unfortunately one died from complications of heart failure. A total of 19 isolates of P. fulva and four of P. putida were identified, of which 20 were from blood, two from environmental surface samples from the hospital pharmacy, and one from an in-use compounded solution from a case-patient in the cardiology ward. Molecular analysis revealed that the P. fulva isolated from the in-use compounded solution (5% glucose solution containing insulin, isosorbide dinitrate, and potassium magnesium aspartate) and the environmental samples had the same PFGE type as the clinical isolates. Conclusions: The investigation identified that contaminated IV solution was the source of the P. fulva bacteremia, which prompted us to implement intensified control measures that resulted in successful control of the outbreak. [ABSTRACT FROM AUTHOR]

Abstract: Background: Severe community-acquired pneumonia (CAP) due to human adenoviruses (HAdVs) in immunocompetent adults has raised concerns. Objective: To describe the clinical, laboratorial, and radiological characteristics of adenovirus pneumonia and detect the type and diversity of human adenoviruses that caused acute respiratory distress syndrome (ARDS) in Beijing. Study design: An etiological study of adult community-acquired pneumonia was carried out prospectively at Beijing Chao-Yang Hospital. A total of 18 cases with laboratory-confirmed adenovirus infections in 487 cases with CAP were observed clinically. The viral type and phylogenetic analysis were tested by polymerase chain reaction (PCR). Results: Patients with adenovirus pneumonia typically reported flu-like symptoms. Some of them developed shortness of breath or severe dyspnea on 6 days after disease onset. The patients with ARDS usually present dyspnea, higher level of serum muscle enzymes and bilateral, mutilobal consolidation and patchy/ground-glass opacities. HAdVs type was detected in 17 samples and all of them belonged to species B (HAdV-11, 7, 3 and 14). Among them, HAdV-11 was most frequently (10/17), followed by HAdV-7 (5/17). Phylogenetic analysis of the partial penton nucleotide confirmed a close relationship with stains circulating in the Beijing region. Conclusions: Our identification of severe respiratory illness due to adenovirus, especially type 11 may highlight the need for rapid diagnosis and improved surveillance, which may assist with targeted development of antiviral agents or type-specific vaccines. [Copyright &y& Elsevier]

Abstract: Among 228 carbapenem-nonsusceptible Enterobacteriaceae isolated in China, 65 were carbapenemase-producing Enterobacteriaceae (CPE). Among them, 41, 22, 1, and 1 produced KPC-2, IMP-4, IMP-8, and IMP-1, respectively. KPC-2-producing CPE showed higher resistance than IMP-4-producing ones. Furthermore, the first outbreak of ST11 KPC-2-producing Klebsiella pneumoniae in a Beijing second-degree hospital was identified. [Copyright &y& Elsevier]