Background Improper settings of outdoor smoking points in public places may increase the risk of secondhand smoke exposure among the population. Conducting research on air pollution in and around smoking spots and related influencing factors can provide valuable insights for optimizing the setting of outdoor smoking points. Objective To investigate the influence of the number of smokers at outdoor smoking points and the distance on the diffusion characteristics of surrounding air pollutants, in order to optimize the setting of outdoor smoking points. Methods Surrounding the exhibition halls in the China International Import Expo (CIIE), two outdoor smoking points were randomly selected, one on the first floor (ground level) and the other on the second floor (16 m above ground), respectively. At 0, 3, 6, and 9 m from the smoking points in the same direction, validated portable air pollutant monitors were used to measure the real-time fine particulate matter (PM_2.5) and carbon dioxide (CO₂) concentrations for consecutive 5 d during the exhibition, as well as the environmental meteorological factors at 0 m with weather meters including wind speed, wind direction, and air pressure. An open outdoor atmospheric background sampling point was selected on each of the two floors to carry out parallel sampling. Simultaneously, the number of smokers at each smoking point were double recorded per minute. The relationships between the number of smokers, distance from the smoking points, and ambient PM_2.5 and CO₂ concentrations were evaluated by generalized additive regression models for time-series data after adjustment of confounders such as temperature, relative humidity, and wind speed. Results The median numbers of smokers at smoking points on the first and second floors were 6 [interquartile range (IQR): 3, 9] and 9 (IQR: 6, 13), respectively. Windless (wind speed <0.6 m·s⁻¹) occupied most of the time (85.9%) at both locations. The average concentration of ambient PM_2.5 at the smoking points (0 m) [mean ± standard deviation, (106±114) μg·m⁻³] was 4.2 times higher than that of the atmospheric background [(25±7) μg·m⁻³], the PM_2.5 concentration showed a gradient decline with the increase of distance from the smoking points, and the average PM_2.5 concentration at 9 m points [(35±22) μg·m⁻³] was close to the background level (1.4 times higher). The maximum concentration of CO₂ [(628±23) μmol·mol⁻¹] was observed at 0 m, and its average value was 1.3 times higher than that of the atmospheric background [(481±40) μmol·mol⁻¹], and there was no gradient decrease in CO₂ concentration with increasing distance at 0, 3, 6, and 9 m points. The regression analyses showed that, taking smoking point as the reference, every 3 m increase in distance was associated with a decrease of ambient PM_2.5 by 24.6 [95% confidence interval (95%CI): 23.5, 25.8] μg·m⁻³ (23.2%) and CO₂ by 54.1 (95%CI: 53.1, 55.1) μmol·mol⁻¹ (8.6%). Every one extra smoker at the smoking point was associated with an average increase of PM_2.5 and CO₂ by 2.0 (95%CI: 1.7, 2.8) μg·m⁻³ and 1.0 (95%CI: 0.7，1.2) μmol·mol⁻¹, respectively. The sensitivity analysis indicated that, under windless conditions, the concentrations of PM_2.5 and CO₂ at the smoking points were even higher but the decreasing and dispersion characteristics remained consistent. Conclusion Outdoor smoking points could significantly increase the PM_2.5 concentrations in the surrounding air and the risks of secondhand smoke exposure, despite of the noticeable decreasing trend with increasing distance. Considering the inevitable poor dispersion conditions such as windless and light wind, outdoor smoking points are recommended to be set at least 9 m or farther away from non-smoking areas.

Objective:To explore the surgical intervention strategy for metastatic cervical lymph nodes surrounding the carotid artery in head and neck squamous cell carcinoma.Methods:A total of 62 patients with advanced head and neck tumors and carotid wrap by disease treated in Department of Otorhinolaryngology and Head and Neck Surgery, the Affiliated BenQ Hospital of Nanjing Medical University between June 2019 and December 2023 were reviewed, of whom 9 patients presented with metastatic squamous cell carcinoma in cervical lymph nodes of unknown primary or with no recurrence of primary lesion and all the 9 patients were males, aged from 48 to 79 years old, with≤level 2 of Eastern Cooperative Oncology Group-Performance Status (ECOG-PS). Radiographically common carotid artery (CCA) and/or internal carotid artery (ICA) were surrounded by≥270° with tumor. All the 9 patients received implantation of covered stent in carotid artery and radical resection of metastatic cervical lymph nodes. The success rate, complications, surgery-related complications, local recurrence rate, quality of life (QOL) and overall survival (OS) were analyzed. The QOL of patients was compared by paired rank sum test, and P<0.05 indicated statistically significant difference. The OS was analyzed by Kaplan-Meier. Results:The success rate of stent implantation was 100%, with no implantation-related complications. R0 resection was performed in 8 cases and R1 resection in 1 case. The QOL of patients after surgery was improved, and the improvements in "pain", "mood" and "anxiety" were statistically significant( Z values were -2.236, -2.460 and -2.200, respectively, and all P values were<0.05). Follow-up was 1-18 months, with a median of 7 months, and 1 case was lost to follow-up. Local recurrence occurred in 3 patients with an incidence of 37.5% (3/8). OS was 59.9% at 12 months after surgery. Conclusion:Implantation of covered stent in carotid artery combined with radical resection is an effective method for the treatment of cervical lymph node metastasis.

Objective:To evaluate the relationship between physical activity (PA) and postoperative delirium (POD) in elderly patients undergoing knee or hip arthroplasty.Methods:The study was conducted as part of the Perioperative Neurocognitive Impairment and Biomarkers Lifestyle Cohort, which was a nested case-control study. Medical records from elderly patients undergoing elective knee or hip arthroplasty under spinal-epidural anesthesia at Qingdao Municipal Hospital from August 2022 to August 2023 were collected. The patients were divided into a POD group ( n=89) and a non-POD group ( n=221) based on the occurrence of POD. Peripheral blood samples were collected before surgery, and the cerebrospinal fluid (CSF) 2 ml was extracted after successful puncture under spinal-epidural anesthesia for determination of the concentrations of amyloid-β 42 (Aβ 42), total tau protein (t-tau), and phosphorylated tau protein (p-tau) by enzyme-linked immunosorbent assay. Logistic regression was used to analyze the influencing factors of POD, and the mediation analysis was conducted to examine the mediating role of CSF biomarker in the relationship between PA and POD. Results:Logistic regression analysis showed that the increased concentration of CSF biomarkers Aβ 42 ( OR=0.997, P=0.006), elevated ratio of Aβ 42/t-tau ( OR=0.642, P=0.003), elevated ratio of Aβ 42/p-tau ratio ( OR=0.872, P=0.001) and PA ( OR=0.374, P=0.001) were protective factors for POD, while the elevated concentrations of t-tau ( OR=1.006, P=0.001) and p-tau ( OR=1.030, P=0.011) were risk factors for POD after adjusting for multi-confounders such as hypertension, diabetes, history of drinking, years of education and Mini-Mental State Examination score. The results of the mediation analysis showed that Aβ 42 (20%), t-tau (16%), Aβ 42/t-tau (23%) and Aβ 42/p-tau (28%) played mediating roles in the relationship between PA and POD. Conclusions:PA is a protective factor for POD in elderly patients undergoing knee or hip arthroplasty and CSF biomarkers may play a mediating role in the relationship between PA and POD.

Objective:To explore the differences in intravascular ultrasound results in elderly coronary heart disease(CHD)patients with different uric acid levels.Methods:A total of 145 elderly patients diagnosed with CHD in our hospital from December 2017 to May 2020 were included as study subjects.Uric acid levels were measured and intravascular ultrasound examination was conducted in all patients.They were divided into different groups based on uric acid levels: Group A(uric acid≤199 μmol/L), Group B(uric acid 200~399 μmol/L)and Group C(uric acid≥400 μmol/L). Data from intravascular ultrasound-derived indexes were analyzed and compared between the three groups.Results:There was no significant difference in the degree of left main stenosis between Group A and Group B, but it was less severe in both groups than in Group C( F=5.625, P=0.039). Plaque fibrous cap thickness showed no significant difference between Group B and Group C, but it was smaller than in Group A( F=7.825, P=0.020). Group C had the largest plaque area and maximum thickness among the three groups, followed by Group B[(11.12±1.73)mm 2 and(1.76±0.24)mm]and Group A[(8.29±3.14)mm 2 and(1.38±0.09)mm]( F=6.384 and 6.827, P=0.028 and 0.015). Conclusions:Elevated uric acid levels in elderly CHD patients can increase the area and thickness of plaques, and reduce plaque fibrous cap thickness, leading to an increased risk of formation of unstable plaques, which can be life-threatening for these patients.Thus, monitoring and managing uric acid levels should be stressed in elderly CHD patients.

Objective: To summarize the clinical characteristics of 141 patients with novel coronavirus pneumonia (NCP) and the imaging characteristics of High Resolution CT(HRCT) in the chest. Methods: From January 20, 2020 to 28, 141 NCP patients, 77 males and 64 females, with a median age of 49 (9,87), were retrospectively analyzed. The clinical features, laboratory examination indexes and HRCT findings of 141 NCP patients were analyzed. Results: In 141 NCP patients, 38 (26.95%) had a decrease in leukocyte count and 71 (50.35%) had a decrease in lymphocyte ratio. Among 141 NCP patients, 139 (98.58%) had fever (over 37.5 ° C), 106 (75.18%) coughed, 11 (7.80%) had headache, 41 (29.08%) coughed up sputum, 93 (65.96%) had chest distress, and 4 (2.84%) had diarrhea. HRCT of 141 NCP patients were abnormal, 52 (36.88%) showed ground glass shadow (GGO) and patchy shadow, mainly subpleural distribution; 23 (16.31%) showed GGO with focal consolidation; 27 (19.15%) had small patchy blur; 20 (14.18%) had large patchy consolidation; 48 (34.04%) had bronchovascular bundle thickening and vascular perforator sign; 5 (3.55%) had Air bronchus sign; small nodule shadow in 7 cases (4.96%); fibrosis, grid shadow or strip shadow in 5 cases (3.55%); bilateral pleural effusion in 7 cases (4.96%); mediastinal or bilateral hilar lymphadenopathy in 4 cases (2.84%). Conclusions The clinical features and HRCT images of NCP are various. Under the specific epidemiological background of NCP, HRCT scan of chest should be carried out in time to make early warning of disease.

Objective:To summarize the clinical and high resolution CT(HRCT) characteristics of 141 patients with COVID-19.Methods:From January 20 to 28, 2020, 141 COVID-19 patients, 77 males and 64 females, with a median age of 49 (9, 87), were enrolled in the study. The clinical features, laboratory test results and HRCT findings of all patients were analyzed retrospectively.Results:In all of the patients, the decreasing leukocyte countin 38 (26.95%) and lymphocyte ratio in 71 (50.35%), a fever over 37.5 ℃ in 139 (98.58%), coughing in 106 (75.18%), headache in 11 (7.80%), expectoration in 41 (29.08%), chest distress in 93 (65.96%), and diarrhea in 4 (2.84%) were found. The HRCT of all patients were abnormal, including ground glass opacity (GGO) with patchy opacity in 52 (36.88%) mainly distributed along subpleural area, GGO with focal consolidation in 23 (16.31%),small patchy opacity in 27 (19.15%),large patchy consolidation in 20 (14.18%),thickened bronchovascular bundleing and blood vessel crossing the lesion in 48 (34.04%), air bronchus sign in 5 (3.55%), small nodule in 7 (4.96%),fibrous stripes and reticular opacities in 5 (3.55%), bilateral pleural effusion in 7 (4.96%), and mediastinal or bilateral hilar lymphadenopathy in 4 (2.84%).Conclusions:The clinical and HRCT manifestations of COVID-19 are various. Under the specific epidemiological background of COVID-19, chest HRCT scan should be carried out as soon as possible for early warning of this disease.

Surgical resection is the best method for patients with colorectal cancer liver metastases. However, tumor recurrence rate is still high after surgery. Preoperative chemotherapy can help shrink the tumor, test biological behavior, and reduce recurrence rate; but it may also cause liver injury and delay surgery. There is still controversy whether neoadjuvant chemotherapy should be performed and how to select patients from chemotherapy before surgery. Thus, in this article, combined the research progress and the clinical experience of author's center, we discuss this issue in 4 aspects: the development of neoadjuvant chemotherapy; the indications and guideline recommendation for neoadjuvant chemotherapy; the selection of neoadjuvant chemotherapy regimens; common problems in neoadjuvant chemotherapy.

Objective The primary goal of this work is to discuss the molecular mechanism of multi-drug resistant Pseudomonas spp. resistance to carbapenam and aminoglycoside antibiotics. Methods From June 2012 to March 2013, six strains of P. aeruginosa and P. putida producing carbapenemasefrom 4 different district were collected. Species identification was performed using VITEK-2 compact system and by sequencing of 16S rDNA amplicons. Minimum inhibitory concentrations were determined by E-test method. Production of carbapenemase were detected by Carba NP method. Carbapenemase genes and aminoglycoside 16s rRNAmethylase genes were screened by PCR, and their subtypes combined with their immediate genetic context were worked out by assemble the sequence of overlapped PCR amplicons. SpeI-PFGE (Pulse field gel electrophoresis after SpeI enzyme digestion) were conducted to evaluate their clonal relatedness. S1-PFGE (Pulse field gel electrophoresis after S1 enzyme digestion) were conducted to conform the relatedness of plasmids they carried. Results Three multidrug resistant P. aeruginosa and three P. putida, were all positive for Carba NP test and conformed producing class B carbapenemase. PCR screening followed by sequencing confirmed carriage of blaIMP-45 and armA, which confer resistance to β-lactams (except aztreonam) and aminoglycosides. These two genes co-located in a Tn1548-associatedregion. SpeI-PFGE disclosed that these isolates were not clonal closely related to each other, except two P. aeruginosa isolates were clonal related. S1-PFGE results showed that these isolates all carried plasmids of large size (300-600 kb). Conclusions This study showed that Pseudomonas spp. isolates co-carried blaIMP-45 and armA were disseminated in clinical settings. Spread of these genes may attribute to horizontal gene transfer of related entities.

Purpose To investigate the reproducibility and risk factors of aortic distensibility quantification in patients with abdominal aortic aneurysm using multi-slice spiral CT.Materials and Methods The abdominal aortic computed tomography angiography data of 54 patients with infrarenal abdominal aortic aneurysm were prospectively studied.64-muti detector spiral CT,retrospective ECG-gating and segment data collecting scanning were all carried out.The aortic distensibility,D value,and pulse wave velocity at renal artery level and infrarenal artery level were calculated using semiautomatic segmentation software.The difference of aortic distensibility at different levels was compared,and consistency test was performed.Results The D value at renal artery level and infrarenal artery level of abdominal aortic aneurysm was (1.05 ±0.22)×10-5/Pa and (0.49± 0.18)× 10-5/Pa,respectively;and the corresponding pulse wave velocity was (9.68± 1.09) m/s and (14.96 ±4.01) m/s,respectively.The intraclass correlation coefficient of intra-and interobserver at renal level was 0.92 and 0.79,while it was 0.85 and 0.79 at inffa level.The Bland-Altman graph showed that the vast majority of points were within the 95％ CI,the difference of intraobserver between the two positions was 0.017×105/pa and 0.010×10-5/Pa,and the difference of interobserver was 0.013×105/Pa and 0.018×10-5/Pa.Multivariate analysis of all these variables showed aortic distensibility to be independently correlated to body mass index,pulse pressure,diastolic pressure and abdominal aortic aneurysm diameter (R2=0.68).Conclusion The quantification of aortic distensibility using multi-slice spiral in patients with abdominal aortic aneurysm shows high stability.Taking into consideration of the relationship between different risk factors and the incidence of abdominal aortic aneurysm can lead to a better clinical approach.

Objective To study the effect on renal function about repeated use of contrast media , and whether alprostadil has protective effect towards contrast-induced nephropathy ( CIN) .Methods 80 adult patients who had ever received contrast examination and scheduled to have PCI within 1 month were randomly divided into two groups: the simple hydration group and the hydration plus alprostadil therapy group.The serum level of creati-nine,urea, Cystatin C, Urineβ-microglobulin and creatinine clearance were recorded and compared between the two groups , and were observed before and after repeated exposure of contrast medium.The incidence of CIN was analyzed .Results Compared with pre-contrast levels , serum levels of urea, creatinin, Cystatin C and Urine β-microglobulin all elevated after single and repeated contrast media use in patients in the simple hydration group ( P<0.05 ) .The incidence of CIN did not differ after single or repeated contrast used (2.5%vs.15.0%, P>0.05).After repeated contrast exposure compared with patients with simple hydration , patients in the alprostadil group had repeated serum levels of urea [(7.4 ±2.3) mmol/L vs.(9.1 ±2.6) mmol/L], creatinia [(87.2 ±25.6) μmol/L vs.(96.9 ± 25.8) μmol/L], Cystatin C [(0.8 ±0.3) mg/L vs.(1.4 ±0.3) mg/L] and Urine β-microglobulin [(207.0 ±31.9 ) μg/L vs.(279.3 ±37.3 ) μg/L] were all lower with higher creatinin clearance [(92.2 ±24.2) ml/min vs.(78.2 ±27.5) ml/min](all P<0.05).The incidence of CIN in patients with alprostadil did not differ after single or repeated contrast used (2.5%vs.7.5%, P>0.05).The incidence of CIN in patients treated with alprostadil had no difference compared with patients with simple hydration after repeated contract (7.5% vs.15.0%, χ2 =0.501,P=0.479).Conclusions Contrast media can cause damage to renal function .Short-term repeated use of contrast media can further worsen renal function without significant increase in CIN rates .Alprostadil may have renoprotective effect towards CIN .