Efficacy and safety of Ruxolitinib, Crisaborole, and Tapinarof for mild-to-moderate atopic dermatitis: a Bayesian network analysis of RCTs.

Given the lack of head-to-head studies of novel non-steroidal molecule topical therapies in mild-to-moderate atopic dermatitis (AD), network meta-analyses (NMAs) can provide comparative efficacy and safety data for clinical decision-making. In this NMA, we performed a literature search until 01 March 2023 for eligible studies written in English using databases, including PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov. Only double-blind randomized clinical trials (RCTs) with topical Ruxolitinib, Crisaborole, or Tapinarof versus vehicle for patients with mild-to-moderate AD were included. Baseline and follow-up data were extracted. Efficacy was evaluated using Investigator's Global Assessment (IGA) achieving "clear" or "almost clear," with 2 points or more improvement from baseline at the end of treatment, referred to as "IGA success." For binary outcomes, we analyzed in random-effects Bayesian NMA consistency models to compare the efficacy of these 3 topical therapies by odds ratio (OR) with 95% credibility interval (CrI). Overall, 10 phase 2 or phase 3 RCTs were identified, which included 4010 patients with mild to moderate AD. Compared with the topical vehicle control, all these 3 treatments had higher response rate of "IGA success" at the end of trial (Ruxolitinib 1.5% b.i.d: OR, 11.94; 95%CrI, 6.28-23.15; Crisaborole 2% b.i.d: OR, 2.08; 95%CrI, 1.46-3.52; Tapinarof 1% b.i.d: OR, 2.64; 95%CrI, 0.75-9.70). Notably, Ruxolitinib 1.5% b.i.d. had the highest probability of achieving "IGA success" in ranking analysis (Rank 1, SUCRA = 0.75) and lower risk of AE (Rank 8, SUCRA = 0.22). Besides, there was no difference in treatment-related adverse events between 3 therapies. Heterogeneity was not significant across studies.

[Occurrence Characteristics of Microplastics and Metal Elements in the Surface Water of Huangpu River and Their Associations with Metal Resistance Genes].

Urban rivers have been regarded as the "hotspots" for microplastic (MPs) and metal contamination as they play important roles in pollution migration. However, as important sinks and sources of resistance genes, there has been little to no research investigating the associations between MPs, metal contaminations, and metal resistance genes (MRGs). Ten water samples were collected from the Huangpu River in situ; along with metal elements, MPs characteristics analyzed. Metal resistance genes and mobile genetic elements (MGEs) in waters and MPs were detected using metagenomic technology. As a result, the highest metal concentration was that of Sb in surface water (3.16±0.419) µg·L-1. The average abundance of MPs was (1.78±0.84) n·L-1, and the peak levels located in industrial and densely populated areas, which was significantly higher than those in agricultural and low population density areas. Fibrous, small-size (<0.5 mm), and transparent polyethylene terephthalate (PET) were the largest contributors of MPs. Eighteen MRGs were detected in all the samples. The relative abundance of MRGs in water was 1.68±0.21. The most dominant MRGs subtypes were merR and ruvB, which are subtypes resistant to mercury and Multi_metals. Correlation analysis showed that chromium and nickel in waters were significantly positively associated with MRG-Cr, MRG-Ni, and Multi_metals resistance genes. For MPs particles, the relative abundance of MRGs was 1.63±0.53. The most dominant MRGs subtypes were merT-P and copB, which also belong to mercury-resistant and Multi_metals. The Multi_metals resistance gene, ctpC, cueA, czrA, kmtR, etc., had significant positive associations with Ni, Cr, and Sb in waters. Compared with water samples, MPs selectively enriched merT-P, copB, ziaA, sodA, and dmeF. Additionally, the co-occurrence patterns of MRGs and MGEs were explored based on network analysis. In water samples, the transposases (tnpA_1 and tnpA_2), integrase (qacEdelta), and insertion sequence (IS91) were the major contributors of the horizontal gene transfer (HGT) of specific MRGs. Multiple subtypes resistant to copper and Multi_metals resistance genes on MPs were positively associated with IncFIC(FII), Rep7, rep7, and rep13, which were subtypes of plasmids. The presence of MPs exerted a significant impact on HGT of specific MRGs mediated by plasmids.

Buffering effect of the economizer against PCDD/Fs in flue gas from solid waste incineration plants.

The emission of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from solid waste incineration is always a crucial concern for the society. Less attention has been paid to differentiate its formation and migration in the low temperature range of economizer, leading to a fuzzy understanding on the control of PCDD/Fs before flue gas cleaning. This study first reveals the buffering effect against PCDD/Fs in the economizer, which is contrary to the well-known memory effect, and first recognizes the intrinsic mechanism by 36 sets of full-scale experimental data under three typical operating conditions. Results indicated that the buffering effect, which includes interception and releasing, could remove averagely 82.9 % of PCDD/Fs in flue gas and reconcile PCDD/Fs profiles. The interception effect is dominant and in compliance with the condensation law. The low temperature range of economizer is exactly suitable for the condensation of lowly chlorinated congeners, which condense behind highly chlorinated ones. The releasing effect was non-staple but stimulated by the sudden change of operating condition, proving that PCDD/Fs formation rarely exists in the economizer. The buffering effect is mainly controlled by the physical migration of PCDD/Fs among different phases. The condensation of PCDD/Fs leads to their migration from vapor phase to aerosol and solid phases during flue gas cooling in the economizer. There is no need for excessive anxiety about PCDD/Fs formation in the economizer because it rarely exists. Intensifying the condensation process of PCDD/Fs in the economizer can help relieve the pressure of end-of-pipe measures for PCDD/Fs control.

Clinical outcomes of diode laser as an adjunct to nonsurgical periodontal therapy for residual periodontal pockets in mandibular second molars-a randomized controlled clinical trial.

OBJECTIVES: The aim of this study was to evaluate the clinical outcomes of diode laser as an adjunct to nonsurgical periodontal therapy (NSPT) for residual periodontal pockets in mandibular second molars. MATERIALS AND METHODS: Sixty-seven mandibular second molars (154 residual periodontal pockets) were recruited into the study and randomly assigned to the Laser + NSPT group and the NSPT group. The Laser + NSPT group underwent NSPT adjunct with diode laser radiation (wavelength: 810 nm, power: 1.5 W, 40 s maximum), while the NSPT group underwent nonsurgical periodontal therapy alone. Clinical parameters were measured at baseline (T0) and 4(T1), 12(T2), and 24(T3), weeks after treatment. RESULTS: Periodontal pocket depth (PPD), clinical attachment loss (CAL), and bleeding on probing (BOP) in both groups showed significant improvements at the end of study compared to baseline. The reductions of PPD, CAL, and BOP in the Laser + NSPT group were significantly greater than NSPT group. At T3, the Laser + NSPT group had a mean PPD of 3.06 ± 0.86 mm, CAL of 2.58 ± 0.94 mm and BOP of 15.49%, while the NSPT group had a mean PPD of 4.46 ± 1.57 mm, CAL of 3.03 ± 1.25 mm and BOP of 64.29%. CONCLUSIONS: The diode laser as an adjunct to nonsurgical periodontal therapy may contribute to clinical outcomes for residual periodontal pockets. However, the approach may cause reduction of keratinized tissue width. TRIAL REGISTRATION NUMBER: This study was registered in the Chinese Clinical Trial Registry ChiCTR2200061194. CLINICAL RELEVANCE: Diode laser as an adjunct to nonsurgical periodontal therapy may contribute to the clinical outcomes for residual periodontal pockets in mandibular second molars.

[Effect of modified holmium laser enucleation of the prostate on postoperative urinary control and sexual function in elderly patients with benign prostatic hyperplasia].

OBJECTIVE: To investigate the impact of retaining part of the urethral mucosa on postoperative urinary control, erectile function, and ejaculatory function in patients undergoing holmium laser enucleation of the prostate (HoLEP) surgery. METHODS: A retrospective analysis was conducted on 176 benign prostatic hyperplasia (BPH) patients who underwent surgical treatment at our hospital from January 2019 to January 2022, including 80 cases of modified HoLEP surgery and 96 cases of standard HoLEP surgery. Preoperative and postoperative clinical data were collected and analyzed. RESULTS: At 3 months postoperatively, both groups showed significant improvement in maximum flow rate (Qmax), International Prostate Symptom Score (IPSS) , residual urine volume (RUV) , and quality of life (QOL) compared to pre-treatment values, with statistically significant differences (P<0.05) . There was a significant difference in QOL scores between the experimental and control groups (P<0.05) . At 3 months postoperatively, the incidence of urinary incontinence was significantly lower in the experimental group compared to the control group (P<0.05) . At 6 months postoperatively, both groups showed a significant increase in International Index of Erectile Function-5 (IIEF-5) scores compared to preoperative values (P<0.05) , with no significant difference between the two groups. The incidence of retrograde ejaculation in the experimental group was significantly lower than that in the control group (P<0.05) . CONCLUSIONS: Retaining part of the urethral mucosa in HoLEP surgery can effectively treat BPH, providing significant advantages in terms of urinary control and playing a positive role in overall postoperative sexual function recovery.

Nomograms for predicting the prognosis of patients with penoscrotal extramammary Paget's disease: A retrospective study in the SEER database and two medical centers.

Background: Extramammary Paget' s disease (EMPD) is a rare cutaneous malignant tumor, and the prognostic factors associated with penoscrotal EMPD remains unclear. The purpose of this study is to investigate prognostic factors and construct nomograms to predict the outcome of patients with EMPD located in the penis or scrotum. Methods: From the Surveillance, Epidemiology and End Results (SEER) database, we extracted 95 patients with primary EMPD located in the penis or scrotum as the training cohort. Forty-nine penoscrotal EMPD patients were included from two medical centers as the external validation cohort. Univariate and multivariate Cox regression model were applied to investigating risk factors of cancer-specific survival (CSS) and overall survival (OS). Based on the results of multivariate Cox regression analysis, the nomograms were constructed for predicting CSS and OS of patients with penoscrotal EMPD. The concordance index (C-index), receiver operating characteristic (ROC) curves and calibration curves were applied to evaluate the practicability and accuracy of the nomograms. Results: In the training cohort, multivariate Cox regression analysis showed that marital status and tumor stage were independent factors of CSS, and marital status, tumor stage and surgery are associated with OS independently in patients with penoscrotal EMPD. Based on these results, we developed nomograms to predict CSS and OS respectively. The C-index values were 0.778 for CSS, and 0.668 for OS in the training set, which displayed the good discriminations. In the external validation set, the C-index values were 0.945 for CSS, and 0.703 for OS. The areas under the curve (AUC) values of nomogram predicting 1-, 3-, and 5-year CSS were 0.815, 0.833, and 0.861 respectively, and 0.839, 0.654, and 0.667 for nomogram predicting 1-, 3-, and 5-year OS respectively. In the validation set, the AUC values of nomogram predicting 1-, 3-, and 5-year CSS were 0.944, 0.896, and 0.896 respectively, and 0.777, 0.762 and 0.692 for nomogram predicting 1-, 3-, and 5-year OS respectively. Additionally, the internal calibration curves also proved that our nomograms have good accuracy. Conclusions: By incorporating marital status, tumor stage and/or surgery, our nomograms can efficiently predict CSS and OS of patients with penoscrotal EMPD.

A novel cone-beam CT scanning technique for measuring periodontal soft tissues in the esthetic area.

PURPOSE: This study investigated and tested a novel cone-beam computed tomography (CBCT) scanning technique capable of obtaining clear contours of soft tissues in the esthetic area. METHODS: Twenty-three periodontally healthy participants underwent this novel CBCT scanning technique. Soft tissue morphological parameters were measured on the CBCT images obtained. Intraoral clinical data were also collected at the same locations, and the accuracy of the CBCT method was tested. RESULTS: The median (interquartile range [IQR]) of the supracrestal gingival tissue thickness as 0.91 (0.73-1.13) mm, and the thickness of the central incisors was significantly greater than that of the canines (P < 0.05). The median (IQR) of keratinized tissue thickness was 0.73 (0.55-0.91) mm, which also showed a significantly greater thickness in the central incisors than in the canines (P < 0.05). Bland-Altman analysis suggested that CBCT could be accurate for measuring soft tissues in the esthetic area. CONCLUSION: The novel CBCT technique described yields clear contours of soft tissues in the esthetic area without the need for auxiliary tools. Moreover, measurements of soft tissue morphological parameters on CBCT appear to be accurate.

Potential urinary biomarkers in young adults with short-term exposure to particulate matter and bioaerosols identified using an unbiased metabolomic approach.

Numerous epidemiological studies have shown a close relationship between outdoor air pollution and increased risks for cancer, infection, and cardiopulmonary diseases. However, very few studies have investigated the potential health effects of coexposure to airborne particulate matter (PM) and bioaerosols through the transmission of infectious agents, particularly under the current circumstances of the coronavirus disease 2019 pandemic. In this study, we aimed to identify urinary metabolite biomarkers that might serve as clinically predictive or diagnostic standards for relevant diseases in a real-time manner. We performed an unbiased gas/liquid chromatography-mass spectroscopy (GC/LC-MS) approach to detect urinary metabolites in 92 samples from young healthy individuals collected at three different time points after exposure to clean air, polluted ambient, or purified air, as well as two additional time points after air repollution or repurification. Subsequently, we compared the metabolomic profiles between the two time points using an integrated analysis, along with Kyoto Encyclopedia of Genes and Genomes-enriched pathway and time-series analysis. We identified 33 and 155 differential metabolites (DMs) associated with PM and bioaerosol exposure using GC/LC-MS and follow-up analyses, respectively. Our findings suggest that 16-dehydroprogesterone and 4-hydroxyphenylethanol in urine samples may serve as potential biomarkers to predict or diagnose PM- or bioaerosol-related diseases, respectively. The results indicated apparent differences between PM- and bioaerosol-associated DMs at five different time points and revealed dynamic alterations in the urinary metabolic profiles of young healthy humans with cyclic exposure to clean and polluted air environments. Our findings will help in investigating the detrimental health effects of short-term coexposure to airborne PM and bioaerosols in a real-time manner and improve clinically predictive or diagnostic strategies for preventing air pollution-related diseases.

Emission of volatile organic compounds (VOCs) from application of commercial pesticides in China.

Applying pesticides can result in emissions of volatile organic compounds (VOCs), but little is known about VOC emission characteristics and the quantities in particular regions. We investigated the use of pesticides in China based on a large-scale survey of 330 counties in 31 provinces and evaluated the national pesticide VOC emission potentials based on thermogravimetric analysis of 1930 commercial pesticides. The results showed that herbicides were the most extensively used pesticide category in China, accounting for 43.47%; emulsifiable concentrate (EC), suspension concentrate, and wettable powder were the dominant pesticide formulations, with proportions of 26.75%, 17.68%, and 17.31%, respectively. The VOC emission potential coefficient (EP) of the liquid formulations was higher than the solid formulations, and the maximum mean EP was 45.59% for EC and the minimum was 0.76% for WP. Among 437 high-VOC pesticide products used in China, EC accounted for 83.52%, and 16.93% of those contained abamectin. The total VOC emissions derived from commercial pesticides in China were 280 kt (kilotons) in 2018, and 65.35% of the contribution was derived from EC. Shandong, Hunan, and Henan were the three provinces with the highest pesticide VOC emissions (>21 kt/y). The emission rate of VOCs from pesticides was 24.80 t/d in China, which was higher than in San Joaquin Valley, California. These findings suggest that some comprehensive measures (e.g., perfecting pesticide management policy, strict supervision for pesticide production and use, and strengthening pesticide reduction publicity) should be taken to reduce VOC emissions from pesticide applications.

A method for constructing GLP-1 overexpression intestinal organoids.

As a potent insulinotrophic hormone, glucagon-like peptide 1 (GLP-1) is mainly secreted by intestinal L cells, which can effectively promote the release of insulin and thus reduce blood glucose. Therefore, GLP-1 and its analogs have a good prospect in the treatment of type 2 diabetes. In this study, we constructed mouse intestinal organoids that overexpress GLP-1 by optimizing the GLP-1 lentivirus infection method. We found that supernatants secreted by the GLP-1 overexpression organoids effectively enhanced glucose tolerance in wild-type and diabetic mouse. Thus, the GLP-1 overexpression organoids built in this study may provide a novel strategy for the treatment of type 2 diabetes.

The Construction and Comprehensive Analysis of Inflammation-Related ceRNA Networks and Tissue-Infiltrating Immune Cells in Ulcerative Progression.

Ulcerative colitis (UC) is a common disease with great variability in severity, with a high recurrence rate and heavy disease burden. In recent years, the different biological functions of competing endogenous RNA (ceRNA) networks of long noncoding RNAs (lncRNAs) and microRNAs (miRs) have aroused wide concerns, the ceRNA network of ulcerative colitis (UC) may have potential research value, and these expressed noncoding RNAs may be involved in the molecular basis of inflammation recurrence and progression. This study analyzed 490 colon samples associated with UC from 4 gene expression microarrays from the GEO database and identified gene modules by weighted correlation network analysis (WGCNA). CIBERSORT detected tissue-infiltrating leukocyte profiling by deconvolution of microarray data. LncBase and multiMIR were used to identify lncRNA-miRNA-mRNA interaction. We constructed a ceRNA network which includes 4 lncRNAs (SH3BP5-AS1, MIR4435-2HG, ENTPD1-AS1, and AC007750.1), 5 miRNAs (miR-141-3p, miR-191-5p, miR-192-5p, miR-194-5p, and miR196-5p), and 52 mRNAs. Those genes are involved in interleukin family signals, neutrophil degranulation, adaptive immunity, and cell adhesion pathways. lncRNA MIR4435-2HG is a variable in the decision tree for moderate-to-severe UC diagnostic prediction. Our work identifies potential regulated inflammation-related lncRNA-miRNA-mRNA regulatory axes. The regulatory axes are dysregulated during the deterioration of UC, suggesting that it is a risk factor for UC progression.

Process tracing of PCDD/Fs from economizer to APCDs during solid waste incineration: Re-formation and transformation mechanisms.

The emission of PCDD/Fs is a crucial factor for the aggravation of the Not-In-My-Back-Yard (NIMBY) syndrome, especially for the incineration plants that fail to meet the emission standard. It is well known that physicochemical processes in the boiler can notably affect the discharge of dioxins, especially under transient, non-steady conditions. However, few studies paid attention to the important operational parameters that influence PCDD/Fs formation and transformation in the boiler when an incinerator is in its daily steady operation. In this study, 36 samples were analyzed to achieve process tracing of PCDD/Fs. The concentration, congener profile and vapor/solid partitions of PCDD/Fs from the economizer to air pollution control devices (APCDs) under two typical steady conditions were investigated. Results indicated that increasing air supply aggravated the formation of PCDD/Fs, disturbed the vapor/solid partitions, and triggered a substandard emission. Quantitative structure-activity relationship (QSAR) modeling was firstly performed for the formation mechanism and orbital energy factors were identified as dominating factors. Besides, the removal rates of PCDD/Fs significantly correlated with the saturated vapor pressure and proportions of different isomers. This study is beneficial for operators to optimize relevant operational parameters of the incineration plants so as to get rid of substandard problems.

Endoscopic submucosal dissection for localised gastric amyloidosis mimicking malignancy / Disección submucosa endoscópica para la amiloidosis localizada gástrica que simula una malignidad

No disponible

Analysis of small bowel angioectasia in asymptomatic individuals depending on patients' age and gender.

Objectives: Small bowel angioectasia (SBA) plays an important role in the etiologies of obscure gastrointestinal haemorrhage. But the exact prevalence of the disease is unknown, especially in asymptomatic populations. Therefore, we aimed to evaluate the prevalence of asymptomatic angioectasia in the small bowel (SB) with magnetically controlled capsule gastroscopy (MCCG).Methods: We retrospectively collected a multicentre clinical data of 508 asymptomatic patients who underwent MCCG from June 2018 to May 2019. Bowel cleanliness was rated as four grades according to the criteria, and the excellent or good preparation was classified as the adequate group. The detection rates of small bowel lesions were analysed according to the ages, genders and bowel preparations.Results: A total of 508 individuals have completed the examination. There were 316 men and 192 women with an average age of 44.5 years old. The prevalence of SBA was 11.8% (95% CI: 9.0-14.6%). 70.0% of them were over 40 years old and 73.3% were male although there was no obvious disparity found in age and gender for the SBA. Most findings were located in the proximal small bowel (jejunum). The incidence of small bowel lesions was not related to bowel preparations (p > .05).Conclusions: SBA is not uncommon in asymptomatic individuals. Age and gender may be risk factors for bleeding of angioectasia in the small bowel, but they seem to have little to do with the occurrence of it. MCCG showed no difference in ages, genders or bowel preparations of small bowel lesions among our study population.

From NIMBY to BIMBY: An evaluation of aesthetic appearance and social sustainability of MSW incineration plants in China.

The Not-In-My-BackYard (NIMBY) claims caused by the rapid expansion of waste incineration in China make stakeholders pay more attention to the environmental and social impact. Nowadays, the environmental impact is under control of the whole society while the social sustainability is often neglected. As the social sustainability is vital to the public acceptance and conducive to convert NIMBY claims to Beauty-In-My-BackYard (BIMBY) synergy, all stakeholders desire to know the gap but lack evaluation method. This paper proposes a quantitative evaluation system for the aesthetic appearance of MSW incineration plants for the first time. It uses aesthetic appearance to measure the social sustainability of MSW incineration plants. Real-world photos of 177 incineration plants in China were collected to support the evaluation using weighted sum method. The weights of factors contributing to the aesthetic appearance were obtained by AHP. The process of pairwise comparison in AHP was conducted by an online questionnaire survey involving more than 100 interviewees in various professions. It is evaluated that the aesthetic appearance is not correlated with the pollution control ability. The spatial distribution of different levels of aesthetic appearance shows that eastern provinces should pay more attention to the improvement of old incineration plants. As case studies, the designs of four typical plants are analyzed. The analysis results reveal the gap between NIMBY plants and BIBMY plants. More importantly, they can contribute to push forward the improvements of aesthetic appearance, social sustainability, and public acceptance for MSW incineration plants in China.

[Role of prostaglandin E2 receptor 4 in cardiovascular diseases].

Prostaglandin E2 (PGE2) is a cyclooxygenase metabolite of arachidonic acid. It acts as a bioactive lipid and plays an important role in regulating many biological processes. PGE2 binds to 4 different G protein-coupled receptors including prostaglandin E2 receptor subtypes EP1, EP2, EP3 and EP4. The EP4 receptor is widely expressed in most of human organs and tissues. Increasing evidence demonstrates that EP4 is essential for cardiovascular homeostasis and participates in the pathogenesis of many cardiovascular diseases. Here we summarize the role of EP4 in the regulation of cardiovascular function and discuss potential mechanisms by which EP4 is involved in the development of cardiovascular disorders with a focus on its effect on inflammation.

Ursolic acid loaded-mesoporous bioglass/chitosan porous scaffolds as drug delivery system for bone regeneration.

Bioglass scaffolds have great application potentials in orthopedics, and Ursolic acid (UA) can effectively promote in vivo new bone formation. Herein, we for the first time developed the mesoporous bioglass/chitosan porous scaffolds loaded with UA (MBG/CS/UA) for enhanced bone regeneration. The MBG microspheres with particle sizes of ~300 nm and pore sizes of ~3.9 nm were uniformly dispersed on the CS films. The mesoporous structure within the MBG microspheres and the hydrogen bonding between the scaffolds and UA drugs made the MBG/CS/UA scaffolds have controlled drug release performances. The as-released UA drugs from the scaffolds increased remarkably the alkaline phosphatase activity, osteogenic differentiation related gene type I collagen, runt-related transcription factor 2 expression, and osteoblast-associated protein expression. Moreover, the results of micro-CT images, histomorphological observations demonstrated that the MBG/CS/UA scaffolds improved new bone formation ability. Therefore, the MBG/CS/UA porous scaffolds can be used as novel bone tissue engineering materials.

Emission characteristics of PCDD/Fs in stack gas from municipal solid waste incineration plants in Northern China.

Emission characteristics including congener's profile, gas emissions and toxic equivalent concentration (TEQ) indicators of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in 57 stack gas samples from 6 municipal solid waste incinerators (MSWIs) in Northern China were investigated by gas chromatography-high resolution mass spectrometry (HRGC-HRMS). Additionally, PCDD/Fs formation mechanisms from the MSWIs were briefly discussed. Results revealed that the concentrations and equivalent concentrations of PCDD/Fs emissions in stack gas from 6 MSWIs were in the range of 0.11-2.53 ng Nm-3 and 0.007-0.059 ng TEQ Nm-3, respectively. The emission factors of PCDD/Fs from 6 MSWIs varied from 0.027 to 0.225 µg I-TEQ tonne-1, with a mean value of 0.17 µg I-TEQ tonne-1 waste, which was estimated to an annual emission of 234.96 mg I-TEQ of PCDD/Fs from 6 MSWIs to the atmosphere. O8CDD, O8CDF and 1,2,3,4,6,7,8-H7CDD were the indicatory compounds of PCDD/Fs to apportion the sources of PCDD/Fs in environmental medium especially in ambient environment of MSWIs. 1,2,3,7,8,9-H6CDF and 1,2,3,4,7,8-H6CDF can be used as TEQ indicators for monitoring PCDD/Fs emission. Based on the positive matrix factorization (PMF) model, eight factors were extracted by the PMF analysis. Formation of low-chlorinated PCDDs (1,2,3,7,8-P5CDD, 1,2,3,4,7,8-H6CDD, 1,2,3,6,7,8-H6CDD and 1,2,3,7,8,9-H6CDD) possessed strong correlation, and the chlorophenols maybe the important precursors of low-chlorinated PCDDs, which were generated within the low chlorinated content. Penta- and hexa-PCDFs formation in stack gas from MSWI may block catalytic sites for PCDFs formation from carbon. Meanwhile, possible formation mechanisms of high-chlorinated PCDDs (hepta- and octa-PCDDs) and high-chlorinated PCDFs (hepta- and octa-PCDFs) were respectively dependent.