Objective To detect the PM_2.5 pollution situation during heating season in Xinxiang university town, analyze the contents of 10 elements in PM_2.5, and evaluate its health risks, so as to provide data support for the subsequent environmental governance of college town. Methods PM_2.5 were collected during heating season. The contents of 10 elements were detected by ICP-MS after PM_2.5 was digested. The source was analyzed using enrichment factor method. The ecological risk and health risk of PM_2.5 was evaluated by applying the potential survival hazard index method and health risk assessment method. Results The average contents of Al, Mg, Mn, Cr, Zn, Se, Cu, Pb, Cd and As were respectively 165.59，203.37，7.75，328.93，133.61，8.24，30.82，7.09，2.77and 9.15 ng/m³. The average contents of Cr, Pb, and As all exceeded their air environment targets. The enrichment factors of Pb, Cu, As, Zn, Cd, Cr and Se were all more than 10, and their sources were affected by human activities. The potential ecological risk index of PM_2.5 was 352.42, which was strong ecological hazard factor. PM_2.5 had carcinogenic risk to human, and the risk in adults was higher than that in children. Conclusion During heating season in Xinxiang college town mainly, PM_2.5 may have short-term health risks on environment and human. When the air quality is poor, it is recommended to reduce outdoor activities while taking personal protective measures to minimize the potential health risks to the population in the university town.

BACKGROUND:Eucommia ulmoides has a certain osteogenic effect,which can promote the proliferation and differentiation of osteoblasts.However,it is unclear whether Eucommia ulmoides has effects on alveolar bone formation and Wnt/β-Catenin signaling pathway. OBJECTIVE:To investigate the mechanism by which Eucommia ulmoides promotes alveolar bone formation in ovariectomized rats based on the Wnt/β-Catenin signaling pathway. METHODS:Sixty female Sprague-Dawley rats were selected and randomly divided into five groups:blank control group,sham-operation group,model group,low-dose group Eucommia ulmoides group,and high-dose Eucommia ulmoides group,with twelve rats in each group.Osteoporosis animal models were constructed by bilateral oophorectomy in the model group and the low-dose and high-dose Eucommia ulmoides groups.The sham-operation group underwent the same method to remove adipose tissue of equal mass around the bilateral ovaries.Three months after surgery,the low-and high-dose Eucommia ulmoides groups were given 2.1 g/kg/d and 4.2 g/kg/d Eucommia ulmoides by gavage,respectively.The sham-operation group and model group were given the same amount of physiological saline by gavage.After 12 weeks of drug intervention,the changes in alveolar bone mass of rats in each group were observed through Micro-CT;hematoxylin-eosin staining was used to observe the pathological structural changes of alveolar bone in rats;enzyme linked immunosorbent assay was used to detect the expression levels of alkaline phosphatase and osteocalcin in the serum of rats;western blot was used to detect the expression levels of β-Catenin and Frizzled9 receptor proteins in the alveolar bone of rats;and real-time fluorescence quantitative PCR was used to detect the expression of osteocalcin,Runt-related transcription factor 2(Runx2),alkaline phosphatase,β-catenin,and frizzled9 mRNAs in alveolar bone tissues of rats. RESULTS AND CONCLUSION:Compared with the blank control group,bone volume fraction,trabecular number,trabecular thickness,and bone mineral density were reduced in the model group(P＜0.05),and trabecular separation was elevated(P＜0.05).Pathological observation showed that the arrangement of trabeculae was disordered and irregular,the trabeculae were thinned or broken,and the marrow cavity was enlarged in the model group,with a significant reduction in bone volume;the level of alkaline phosphatase in the serum was increased(P＜0.05),and the level of osteocalcin was decreased(P＜0.05);mRNA expression of alkaline phosphatase,osteocalcin,Runx2,β-catenin,and frizzled9 were decreased(P＜0.05);protein expression of β-Catenin and Frizzled9 was decreased(P＜0.05).Compared with the model group,the low-and high-dose Eucommia ulmoides groups showed an increase in bone volume fraction,trabecular number,trabecular thickness,and bone mineral density(P＜0.05)and a decrease in trabecular separation(P＜0.05).In the low-and high-dose Eucommia ulmoides groups,bone trabeculae were slightly aligned and thickened,with a significant increase in bone mass.Compared with the model group,the serum level of alkaline phosphatase was reduced(P＜0.05)and the serum level of osteocalcin was elevated(P＜0.05)in the low-and high-dose Eucommia ulmoides groups.Compared with the model group,the mRNA expression of alkaline phosphatase,osteocalcin,Runx2,β-catenin,and frizzled9 were increased in the low-and high-dose Eucommia ulmoides groups(P＜0.05).Compared with the model group,the protein expression of Frizzled9 was increased in the low-dose Eucommia ulmoides group(P＜0.05),while the protein expression of β-Catenin and Frizzled9 was increased in the high-dose Eucommia ulmoides group(P＜0.05).Compared with the low-dose Eucommia ulmoides group,the high-dose Eucommia ulmoides group had a more significant improvement in the above indexes.To conclude,Eucommia ulmoides can effectively promote the alveolar bone formation,and its mechanism of action might be related to the activation of the Wnt/β-catenin signaling pathway.

OBJECTIVE T o investigate the data and usage,effectiveness and existing issues of three medical quality control indicators for hospital-associated infection management(2015 Edition),including hospital-associated infec-tion incidence rate,hospital-associated infection prevalence rate and hospital-associated infection underreporting rate.METHODS Data from hospitals that participated in reporting for three consecutive years(2018-2020)prior to the survey were selected for analysis through the annual professional quality control work conducted by the Na-tional Nosocomial Infection Management and Quality Control Center.An online questionnaire-based sampling sur-vey was conducted to evaluate the usage of the aforementioned three hospital-associated infection quality control in-dicators.RESULTS The usage rates of the three indicators were above 80％in hospitals of different levels and types.For the two indicators of hospital-associated infection incidence rate and hospital-associated infection under-reporting rate,the usage rates were higher in tertiary hospitals than in secondary hospitals,and higher in general hospitals than in specialized hospitals(P＜0.05).For the hospital-associated infection prevalence rate indicator,the usage rate was 96.01％in tertiary hospitals,higher than that in secondary hospitals(90.73％),with a statisti-cally significant difference(P＜0.05).The usage rate of such indicator was also higher in general hospitals(92.22％)than in specialized hospitals(89.50％)(P=0.102).Regarding self-evaluatio n of the implementation ef-fectiveness of the hospital-associated infection incidence rate,statistically significant differences were found among hospitals of different levels and types(P＜0.001).For self-assessment of the implementation effectiveness of the hospital-associated infection prevalence rate and hospital-associated infection underreporting rate,statistically sig-nificant differences were found among hospitals of different levels(P＜0.001).CONCLUSIONS The three indica-tors,hospital-associated infection incidence rate,hospital-associated infection prevalence rate and hospital-associ-ated infection underreporting rate,have been stable overall in the past three years.There are certain differences in their usage and evaluation.Reasonable revisions should be made based on actual situations to better guide clini-cal infection control work.

In recent years the detection rate of Elizabethkingia anopheles(EA)in China has shown an upward trend,making it one of the important pathogens causing hospital and community infections.EA accounts for 59.3％to 96.2％of the Elizabethkingia species,and can cause meningitis,pneumonia,bacteremia,etc.There are limited researches on its pathogenic mechanism,which mainly involves various virulence factors.EA is a mul-tidrug-resistant bacterium,with drug resistance mechanisms including biofilm formation,efflux pumps and carry-ing multiple resistance genes(such as GOB,BlaB).Currently,minocycline,piperacillin/tazobactam,trime-thoprim/sulfamethoxazole and rifampin are effective drugs for treating EA infections.Clinically,efforts are be-ing made to find the optimal antibacterial drug combination to achieve ideal therapeutic effects.This paper reviews the epidemiological characteristics,pathogenic mechanisms,drug resistance mechanisms and treatment options of EA,aiming to provide a reference for clinical prevention,control,diagnosis and treatment of EA infections.

Objective:To investigate and summarize the imaging and pathological features of non-acute occlusion following flow diverter (FD) implantation in animal models.Methods:Four experimental pigs (experimental group) that experienced non-acute occlusion (occlusion time exceeding 24 hours) within the FD stent implanted in the common carotid artery, and 19 pigs (control group) that did not experience stent occlusion during the same period were involved. Using an interventional approach under digital subtraction angiography (DSA), the 4 occluded FD lumens were mechanically opened. Optical coherence tomography (OCT), intravascular ultrasound (IVUS) and histopathological examinations were performed to evaluate the intraluminal composition and characteristics of the occlusive tissues. These findings were compared with non-occluded FD stents to summarize the imaging and pathological changes within the occluded FD lumen.Results:The occlusion times of the FD stents in the 4 experimental pigs were 16 weeks, 20 weeks, 20 weeks, and 24 weeks postoperatively. All occluded stents were successfully recanalized under DSA, with a technical success rate of 4/4. Among the 19 non-occluded FD stents, OCT and IVUS revealed uniform (16 stents) or non-uniform (3 stents) neointimal coverage of the stent struts, presenting as homogeneous high/slightly high signal intensity or medium echogenicity. Histopathological examination indicated that the neointima was primarily composed of smooth muscle cells and a small amount of fibrous connective tissues. In contrast, the 4 occluded FD stents demonstrated excessive neointimal proliferation and plaque formation, leading to luminal loss, as shown by OCT and IVUS. The occlusion tissues predominantly presented as homogeneous high signal intensity with weak attenuation (fibrous plaques) on OCT, with some regions showing blurred low signal intensity and strong attenuation (lipid plaques). IVUS presented homogeneous echogenicity (fibrous plaques) and hypoechogenic zones (lipid plaques). Histopathological examination showed that the occlusion tissues mainly consisted of smooth muscle cells, fibrous connective tissues, and lipids, accompanied by numerous foam cells and a minor presence of inflammatory cells.Conclusions:Histopathological examinations confirm that non-acute occlusion of FD is mainly caused by excessive hyperplasia of intima along with the formation of fibrous plaques and lipid plaques. OCT and IVUS have typical finding in imaging that can assist in determining the cause of stent occlusion as well as the lesion's nature, thereby providing crucial guidance for subsequent clinical treatment and drug selection.