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Polycyclic aromatic hydrocarbons (PAHs) have carcinogenic impacts on human health. However, limited studies are available on the characteristics, sources, and source-specific health risks of PM2.5-bound PAHs based on personal exposure data, and comparisons of the contributions of indoor and outdoor sources are also lacking. We recruited 101 senior citizens in the winter of 2011 for personal PM2.5 sample collection. Fourteen PAHs were analyzed, potential sources were apportioned using positive matrix factorization (PMF), and inhalational carcinogenic risks of each source were estimated. Six emission sources were identified, including coal combustion, gasoline emission, diesel emission, biomass burning, cooking, and environmental tobacco smoking (ETS). The contribution to carcinogenic risk of each source occurred in the following sequence: biomass burning > diesel emission > gasoline emission > ETS > coal combustion > cooking. Moreover, the contributions of biomass burning, diesel emission, ETS, and indoor sources (sum of cooking and ETS) to PAH-induced carcinogenic risk were higher than those to the PAH mass concentration, suggesting severe carcinogenic risk per unit contribution. This study revealed the contribution of indoor and outdoor sources to mass concentration and carcinogenic risk of PM2.5-bound PAHs, which could act as a guide to mitigate the exposure level and risk of PM2.5-bound PAHs.

Systemic inflammation is a key mechanism in the development of cardiovascular diseases induced by exposure to fine particles (particles with aerodynamic diameter ≤2.5 μm [PM

BackgroundTo explore the surgical outcomes between patients with perforated and non-perforated neonatal necrotizing enterocolitis (NEC) and identify indications for surgical intervention.MethodsThe surgical outcomes of 271 children with NEC admitted to the Seventh Medical Center of Chinese PLA General Hospital between August 2009 and August 2020 were retrospectively analyzed. The patients were divided into the non-perforated and perforated groups. The preoperative factors, including gestational age, birth weight, intrauterine infection, cholestasis, platelet change, white blood cell count, and C-reactive protein level were compared between the two groups, along with postoperative factors including infection status, complications, enteral and parenteral nutrition time, ICU time, ventilator use time, and intestinal necrosis length. Bell staging was performed for the two groups and the mortality of different Bell stages was explored. The risk of death and predisposing factors of patients with NEC were analyzed.ResultsIn total, 271 children undergoing surgery were included in this study. A total of 188 children were observed without perforation, including 57 deaths (30.3%), and 83 children with perforation, including 24 deaths (28.9%). Preoperative cholestasis and time from NEC diagnosis to surgery were significantly different between the two groups (P < 0.05). Postoperative factors, including parenteral nutrition time (32 [3–94] days vs. 23 [1–53] days), enteral nutrition time (27 [0–86] days vs. 18 [0–81] days), NICU time (44 [5–125] days vs. 29 [1–92] days), and length of intestinal necrosis (15 [0–92] cm vs. 10 [2–70] cm), were significant. The mortality rate of patients with Bell stage IIIA was higher than that of patients with Bell stage IIIB. A total of 81 patients had 30-day postoperative mortality (57 non-perforated cases). Multivariate Cox regression analysis showed that non-perforation was a poor prognostic factor for survival outcome (hazard ratio 2.288, 95% confidence interval [1.329-3.940], P = 0.003).ConclusionsPreterm infants in the non-perforated group had more serious complications and had a longer recovery time after surgery. Bell staging is not accurate in diagnosing severe NEC that needs surgical intervention.

Ten nitrated polycyclic aromatic hydrocarbons (nPAHs) and 4 oxygenated polycyclic aromatic hydrocarbons (oPAHs) in fine particulate matter (PM2.5) samples from Mount Tai were analyzed during summer (June to August), 2015. During the observation campaign, the mean concentration of total nPAHs and oPAHs was 31.62 pg/m3 and 0.15 ng/m3, respectively. Two of the monitored compounds, namely 9-nitro-anthracene (9N-ANT) (6.86 pg/m3) and 9-fluorenone (9FO) (0.05 ng/m3) were the predominant compounds of nPAHs and oPAHs, respectively. The potential source and long-range transportation of nPAHs and oPAHs were investigated by the positive matrix factorization (PMF) method and the potential source contribution function (PSCF) methods. The results revealed that biomass/coal burning, gasoline vehicle emission, diesel vehicle emission and secondary formation were the dominant sources of nPAHs and oPAHs, which were mainly from Henan province and Beijing-Tianjin-Hebei region and Bohai sea. The incremental life cancer risk (ILCR) values were calculated to evaluate the exposure risk of nPAHs and oPAHs for three group people (infant, children and adult), and the values of ILCR were 7.02 × 10−10, 3.49 × 10−9 and 1.41 × 10−8 for infant, children and adults, respectively. All these values were lower than the standard of EPA (Environmental Protection Agency) (

Sixty-four bottom ash (BA) samples from indoor burning of eight bio-fuels (BFs) including cotton (COT), corn (COR), millet (MIL), soybean (SOY), sorghum (SOR) and sesame (SES), firewood walnut (WAL), and corn cob (COC) were collected across the Beijing-Tianjin-Hebei (BTH) region. Each BA was divided into five differently sized parts for the analysis of eighteen PAHs using the GC/MS system. The Σ18PAHs values for all the BAs varied from 65.0 ± 10.6 to 1310 ± 129 ng g–1. SOR had the highest PAH level, and COC produced the lowest level. The Σ18PAHs for SOY, WAL, COT, COR, COC, and SES were negatively correlated with the BA sizes. The NA, PHE, ACL, AN, FA, PY, FL, and AC dominated in all the BAs except for SES. All the BAs were dominated by 2, 3-ring PAHs. The PAH profiles for differently sized BAs within MIL, SOR, COC, COR, and SES were similar based on lower coefficient of divergence values, while the other three BFs did not exhibit this trend. All the BF pairs except for SOR vs. SES and COC vs. COR had the different PAH profiles. No series of coincident diagnostic ratios (DRs) could represent all BFs based on their significantly varied DRs. AN/(AN + PHE) and BA/BgP might be used in identification of combustion sources of different types of BFs. SOR and SES had higher potential toxicity risk based on higher TEQ, BaPE, and CPAHs values. BgF and BgP were the indicatory PAHs for SOY, MIL, COR, SOR, and COC, while they were AC and FL for the remaining three BFs.

Particulate matter with an aerodynamic diameter of 2.5 μm or less (PM 2.5 ) is the main air pollutant in many countries. PM 2.5 levels vary substantially over time and short distances, which directly affects the interpretation of data collected from reference stations. Although such data are usually accurate for one location at a certain time, they cannot be extrapolated to carry out complete spatial and temporal PM 2.5 assessment. China’s varying geographies, climates and environment make it challenging to accurately measure ambient air PM 2.5 levels. This paper describes the current state of PM 2.5 pollution and standard/specifications of monitoring in China, reviews all available PM measurement techniques, highlights the advantages and limitations of the most widely used instruments, and discusses the related challenges. Based on our analysis of PM 2.5 measurements, we suggest some ways to improve this measurement in China. In particular, suitable instruments need to be developed to accommodate different environments, climates and pollution levels across China. However, it is important to note that monitoring is merely a way to measure pollution levels, and not the main purpose of our research. The final purpose we have is creating a healthy and comfortable living environment for China’s residents.

The chemical profiles of emission sources are indispensable for source apportionment using receptor models. To develop current knowledge of PM10 profiles, the chemical composition of major emission sources were analyzed in Xining. Samples of geological sources (soil dust, road dust and construction derived dust) and industrial fly ash were collected from representative portions using a plastic dustpan and brush and sampled on filters through a re-suspension chamber. Samples of coal combustion source and vehicle exhaust were collected directly on the filters using a dilution stack sampler. Chemical analysis included inductively coupled plasma mass spectrometry for 19 elements (Na, P, K, As, Rb, Mo, Cd, Sn, Sb, La, V, Cr, Mn, Co, Ni, Cu, Zn, T1, and Pb), inductively coupled plasma optical emission spectrometry for 7 elements (Al, Sr, Mg, Ti, Ca, Fe, and Si), ion chromatography for water-soluble ions (Na + , K + , Mg 2+ , Ca 2+ , F – , Cl – , NO3 – and SO4 2– ) and thermal/optical reflectance analysis for carbonaceous species. Crustal elements (Si, Al, Ca, Fe) predominated in geological sources, whereas trace elements (Pb, Cd, Cr, Zn and Ni) were predominant in industrial fly ash. An abundance of carbon and SO4 2– was present in coal-combustion source and vehicle exhaust. The coal-combustion boilers were a source of trace elements (Ti, Co, Sr, Sb, Tl). High concentrations of Pb and OC in soil indicated the strong influence of agriculture activities in Xining. Comparison of vehicle exhaust profiles indicated that natural gas was high environmental friendliness in comparison with petroleum products used as motor vehicles fuel. Differences in EC, Cd and NO3 – between natural gas-powered and gasoline- or diesel-powered vehicle exhaust can be used to differentiate the two types of vehicle emission sources. Differences in source profiles and indicator species between Xining and other cities suggest that source profiles should be developed locally and updated frequently.

To compare the effect of decimeter wave with sodium hyaluronate product (SHP) on preventing and treating peritendinous adhesion and promoting tendon healing.Totally 96 healthy male white 6-month-old Leghorn chickens weighing (2.24 +/- 0.07) kg were randomized into group A (decimeter wave therapy group, n = 32), in which decimeter wave therapy was applied 1 to 21 days after operation at a frequency of 915 MHz, a power of 8 W, radiation distance of 10 cm, for 10 minutes once per day; group B (SHP group, n = 32), in which 5 mL and 1.2% SHP was applied; and group C (control group, n = 32), in which injury received no treatment. The III and IV toes of left feet of all chickens were made into tendon injury model. The general condition of animal was observed after operation; gross and histological observations were made 7, 10, 14, 18, 21 and 28 days after operation, and the biomechanical analysis was done 14 and 28 days after operation.Operative incision healed well, no infection and death occurred. Peritendinous adhesions in groups A, B were looser, and tendon healing was better than that of group C 14 and 28 days after operation. More fibroblasts with active metabolism and more collagen formation in groups A, B than that in group C. The Pmax of group A was better than that of group B 14 and 28 days after operation (P0.05); the delta max of group A was better than that of group B 18 and 21 days after operation (P0.05), and the W0 of group A was better than that of group B 18, 21 and 28 days after operation (P0.05). There was no significant difference between group A and group B at the other time points.Topical decimeter wave therapy and application of SHP after flexor tendon repair can promote intrinsic healing, meanwhile they can prevent the adhesion of tendon and reduce extrinsic healing. Decimeter wave therapy can improve the qualities of tendon's wound healing.

To explore a method of treating Madelung deformity.Seven cases of Madelung deformity had been treated with the excision of ulnar carpi ulnaris segment and distal osteotomy of radius and tight constrict of extensor carpi ulnaris from Mar. 2000 to Nov. 2003. The angle of ulnar tilting was 37-70 degrees and the angle of volar tilting was over 16 degrees. A longitudinal incision on each side of the radius and ulnar was made, the ulna was excised about 2-3 cm segment. Then the fracture of ulna was fixed by double across vertical steel wire and the radius was fixed with medullary wire. Lastly the extensor carpi ulnaris was shortened and sutured after the wrist was located rest-position.After surgery, the deformity of wrist was improved and pain-free in the seven cases. The angle of ulnar tilting was reduced to 22-24 degrees. The angle of volar tilting was reduced to 15 degrees below. Follow-ups were conducted in the 7 patients for 2 years in average. The activity of wrist joint and the rotation of forearm recovered from those before operation. The wrist joint could stretch fully.This method of treating Madelung proves to be effective in recovering deformity, releasing pain, improving function, and reducing traumatic osteoarthritics of the distal radioulnar joint.