Background Bacteria are the most diverse and widely sourced microorganisms in the indoor air of subway stations, where pathogenic bacteria can spread through the air, leading to increased health risks. Objective To understand the status and distribution characteristics of indoor air bacterial pollution in subway stations and compartments in a city of Central South China, and to provide a scientific basis for formulating intervention measures to address indoor air bacteria pollution in subways. Methods Three subway stations and the compartments of trains parking there in a city in Central South China were selected according to passenger flow for synchronous air sampling and monitoring. Temperature, humidity, wind speed, carbon dioxide (CO₂), fine particulate matter (PM_2.5), and inhalable particulate matter (PM₁₀) were measured by direct reading method. In accordance with the requirements of Examination methods for public places-Part 3: Airborne microorganisms (GB/T 18204.3-2013), air samples were collected at a flow rate of 28.3 L·min⁻¹, and total bacterial count was estimated. Bacterial microbial species were identified with a mass spectrometer and pathogenic bacteria were distinguished from non-pathogenic bacteria according to the Catalogue of pathogenic microorganisms transmitted to human beings issued by National Health Commission. Kruskal-Wallis H test was used to compare the subway hygiene indicators in different regions and time periods, and Bonferroni test was used for pairwise comparison. Spearman correlation test was used to evaluate the correlation between CO₂ concentration and total bacterial count. Results The pass rates were 100.0% for airborne total bacteria count, PM_2.5, and PM₁₀ in the subway stations and train compartments, 94.4% for temperature and wind speed, 98.6% for CO₂, but 0% for humidity. The overall median (P₂₅, P₇₅) total bacteria count was 177 (138,262) CFU·m⁻³. Specifically, the total bacteria count was higher in station halls than in platforms, and higher during morning peak hours than during evening peak hours (P<0.05). A total of 874 strains and 82 species were identified by automatic microbial mass spectrometry. The results of identification were all over 9 points, and the predominant bacteria in the air were Micrococcus luteus (52.2%) and Staphylococcus hominis (9.8%). Three pathogens, Acinetobacter baumannii (0.3%), Corynebacterium striatum (0.1%), and Staphylococcus epidermidis bacilli (2.2%) were detected in 23 samples (2.6%), and the associated locations were mainly distributed in train compartments during evening rush hours. Conclusion The total bacteria count in indoor air varies by monitoring sites of subway stations and time periods, and there is a risk of opportunistic bacterial infection. Attention should be paid to cleaning and disinfection during peak passenger flow hours in all areas.

Multimorbidity is significantly associated with life quality decline, disability, and increased mortality risk. Additionally, it leads to greater consumption of healthcare resources, presenting substantial challenges to healthcare systems globally. To better assess the burden of multimorbidity, its impact on patient health outcomes and healthcare services, and to explore the underlying mechanisms in its development, this paper summarizes the existing methods used for measuring and analyzing multimorbidity in research and practice, including disease count, disease-weighted indices, multimorbidity pattern recognition (such as disease association analysis, clustering analysis, and network analysis) and longitudinal methods to provide references for the accurate assessment of the prevalence of multimorbidity and its changes and improve the validity and universality of research findings.

AIM:To explore the effect of microRNA-184(miR-184)on compensatory lung growth(CLG)af-ter lobectomy in multiple primary lung cancer(MPLC)and its mechanism.METHODS:(1)Lung tissue samples(n= 16)from MPLC patients and patients with good recovery after lobectomy(CLG)were collected,and the expression of miR-184 was measured by RT-qPCR.(2)Human alveolar epithelial cells were divided into NC-mimic group,miR-184 mimic group,OE-NC group,tissue inhibitor of metalloproteinase-2(TIMP-2)overexpression(OE-TIMP-2)group,and miR-184 mimic+OE-TIMP-2 group according to the transfection(n=3).The expression of miR-184,TIMP-2 mRNA and matrix metalloproteinase-14(MMP-14)mRNA was measured by RT-qPCR,and the protein expression of TIMP-2 and MMP-14 was determined by Western blot.The proliferation of the cells was measured by CCK-8 and colony formation assays.(3)C57BL/6J mice were divided into pneumonectomy(PNX)group and PNX+miR-184 mimic group(n=5).The flexiVent system was used to measure the vital capacity and lung compliance of the mice.Lung volume was measured by water dis-placement method,and lung tissue changes were observed by HE staining.RESULTS:The expression of miR-184 was significantly higher in the patients with better recovery after lobectomy(P＜0.01).Overexpression of miR-184 promoted the proliferation of human alveolar epithelial cells and the recovery of lung function in mice after PNX.In terms of mecha-nism,miR-184 showed targeted binding with TIMP-2,and overexpression of miR-184 promoted the expression of MMP-14 by inhibiting TIMP-2,thereby promoting the proliferation of human alveolar epithelial cells and the recovery of mouse lung function after PNX.CONCLUSION:miR-184 promotes CLG after PNX through the TIMP-2/MMP-14 axis.

Background:Previous study has found that harmine inhibited the proliferation of gastric cancer cells by down-regulating cyclooxygenase-2(COX-2)expression. However,its molecular mechanism is not fully clear. Aims:To investigate the effect of harmine on proliferation and apoptosis of gastric cancer cells,and explore the role of PTEN/Akt/MDM2 signaling pathway in this process. Methods:Human gastric adenocarcinoma cell line SGC-7901 and MKN-45 were treated with harmine at different concentrations(2,4,8,16,32 μg/mL)for 24,48,and 72 hours. The cell proliferation and apoptosis were detected by MTT assay and Hoechst staining,respectively. The expressions of PTEN,COX-2, phosphorylated Akt(p-Akt)and p-MDM2 were measured by Western blotting. Results:Harmine dose- and time-dependently inhibited proliferation and induced apoptosis of SGC-7901 and MKN-45 cells. Also,harmine dose-dependently increased PTEN expression,and inhibited p-Akt,p-MDM2 and COX-2 expressions in SGC-7901 and MKN-45 cells. Conclusions:Harmine may inhibit proliferation and induce apoptosis of gastric cancer cells via down-regulating COX-2 expression through PTEN/Akt/MDM2 signaling pathway.

Background: Previous study has found that ursolic acid (UA) inhibited the proliferation of gastric cancer cells by the down-regulation of cyclooxygenase-2 (COX-2) expression.However,its molecular mechanism is not fully clear.Aims: To investigate the role of adenosine monophosphate-activated protein kinase (AMPK)/signal transducer and activator of transcription 3 (STAT3)/COX-2 signaling pathway in UA-mediated inhibition of gastric cancer cells proliferation.Methods: AMPK-pLVX,AMPK-shRNA,STAT3-pLVX,STAT3-shRNA plasmids were constructed,and then were transfected into human gastric cancer cell lines SGC-7901 and MKN-45,respectively.Gastric cancer cells were cultured with different concentrations of UA for different times.The expressions of phosphorylated AMPK (p-AMPK),phosphorylated STAT3 (p-STAT3) and COX-2 were measured by Western blotting,and cell proliferation was detected by CCK-8 assay.Results: UA dose-and time-dependently increased p-AMPK expression,inhibited p-STAT3 and COX-2 expressions in SGC-7901 and MKN-45 cells.Knockdown of AMPK blocked UA-induced inhibition of STAT3 phosphorylation and COX-2 expression.Overexpression of STAT3 blocked UA-induced down-regulation of COX-2 expression.Knockdown of AMPK and overexpression of STAT3 blocked UA-induced inhibition of proliferation of gastric cancer cells.Conclusions: UA may inhibit the proliferation of gastric cancer cells via down-regulation of COX-2 expression through AMPK/STAT3 pathway.

Objective To evaluate the relationship of preoperative neutrophil-lymphocyte ratio (NLR) with clinicopathological features and prognosis of colorectal cancer in middle-aged and elderly patients.Methods A retrospective analysis was performed in 212 patients with colorectal cancer in the First Affiliated Hospital of Nanjing Medical University from January 2011 to June 2013.All patients were divided into middle-aged group (46-65 year old,n=130) and old-aged group (66-89 year old,n=82),The optimal cut-off point of NLR was identified by the area under receiver operating characteristic curve,while NLR ＞ 3.13 and NLR≤3.13 were classified as high and low NLR group.The clinicopathological features and prognosis between the two groups were compared.Results There was no difference in gender,tumor growth site,depth of invasion,tumor embolus,lymphatic metastasis,distant metastasis,TNM stage between low and high NLR group (allP＞ 0.05).However,the difference between high NLR group and low NLR group in old-aged group with diabetes mellitus was statistically significant (P＜0.05).The 1-,2-,and 3-year survival rate of the overall 212 patients were 96.2％ (204/212),87.7％ (186/212) and 74.5％ (158/212) In middle-aged group,the 1-,2-,and 3-year survival rates were 98.8％ (85/86),90.7％ (78/86) and 84.9％ (73/86) respectively in low NLR group,but 95.5％ (42/44),84.1％ (37/44) and 72.7％ (32/44) respectively in high NLR group,(allP＜0.05).In old-aged group,the 1-,2-,and 3-year survival rates were 95.7％ (44/46),89.1％ (41/46) and 73.9％ (34/46) respectively in low NLR group,but 91.7％ (33/ 36),83.3％ (30/36) and 52.8％ (19/36) respectively in high NLR group (all P＜0.05).Cox regression showed that TNM stage and NLR were independent risk factors for the prognosis of the middle-aged and elderly patients with colorectal cancer (P＜0.05 or P＜0.01).Conclusions Preoperative NLR ＞ 3.13 suggest that the prognosis is poor in middle-aged and elderly patients with colorectal cancer.

Objective To evaluate the clinical application of enteral nutrition by nasojejunal tube insertion and by percutaneous endoscopic gastrostomy (PEG) in elderly patients.Methods A total of 65 elderly patients with dysphagia recruited at our department from January 2010 to November 2014 were divided into the nasojejunal tube feeding group (35 cases) and the PEG feeding group (30 cases).Differences between these two groups in nutritional indexes,immunological indexes,complications and mortality were analyzed retrospectively.Results Serum total protein,albumin and prealbumin and upper arm circumferences all increased after treatment with nasojejunal tube feeding or percutaneous endoscopic gastrostomy (P＞0.05).There was overall improvement in nutritional status,as assessed by Nutritional Risk Screening 2002 (NRS2002).Specifically,the before/one month-after-treatment ratio of scores was 3.72±0.91/1.90±0.61 (t=7.24,P＜0.01) for the nasojejunal tube feeding group and 3.52±1.23/2.02±0.53 (t=4.17,P＜0.01) for the PEG feeding group.Compared with NRS2002 scores at one month post-operation,further improvement was achieved at 3 months postoperation both for the nasojejunal tube feeding group (1.89±0.65,t=5.21,P＜0.01) and for the PEG feeding group (1.91±0.62,t=4.40,P＜0.01).There was no difference in the indexes of nutrition,immune status or mortality between the two groups (P＞0.05).Although improvement in CD3+,CD4+,CD8+,CD4+/CD8+,IgA,IgG,and IgM was seen in both groups after operation,the differences did not reach statistical significance (P＞0.05).The incidence of aspiration pneumonia was notably lower (P＜0.05) while the incidence of diarrhea was much higher (P＜0.05) in the nasojejunal tube feeding group than in the PEG feeding group at one month and three months.The two groups had similar causes of death and mortality rates.Conclusion Both nasojejunal tube and PEG feeding can improve the nutritional status of elderly patients with dysphagia.However,the choice for the route of nutrition should be individualized.

Aim Our previous study has found that ur-solic acid( UA) increased intracellular reactive oxygen species ( ROS ) production and adenosine monophos-phate-activated protein kinase ( AMPK ) phosphoryla-tion, inhibited signal transducer and activator of tran-scription 3 ( STAT3 ) phosphorylation and cyclooxygen-ase-2 ( COX-2 ) expression in gastric cancer cells . However , the molecular mechanism by which UA in-hibits COX-2 expression in gastric cancer cells has not been fully clarified .In this study we aimed to further clarify the signal transduction pathways involved in the UA-mediated inhibition of COX-2 expression in gastric cancer cells .Methods Human gastric cancer cell lines SGC-7901 and MKN-45 were routinely cultured in RPMI-1640 medium supplemented with 10% heat-in-activated fetal calf serum .Sub-confluent cell cultures were pre-treated with antioxidant N-acetylcysteine ( NAC) , AMPK activator 5-amino-4-imida-zolecarbox-amide-riboside ( AICAR ) , AMPK inhibitor compound C, or STAT3 inhibitor WP1066 and then treated with or without UA for 24 h.The expression of AMPK and phosphorylated AMPK ( p-AMPK ) , STAT3 and phos-phorylated STAT3 ( p-STAT3 ) , as well as COX-2 was detected by Western blot analysis .Results Antioxi-dant NAC and AMPK inhibitor compound C blocked UA-induced inhibition of STAT 3 phosphorylation and down-regulation of COX-2 expression in gastric cancer cells.Both AMPK activator AICAR and UA inhibited STAT3 phosphorylation and COX-2 expression; the combination of two drugs resulted in further reduction . STAT3 inhibitor WP1066 did not affect UA-induced AMPK phosphorylation , whereas it inhibited STAT3 phosphorylation and COX-2 expression .The inhibitory effects on the STAT3 phosphorylation and COX-2 ex-pression were significantly enhanced when SGC-7901 and MKN-45 cells were treated simultaneously with WP1066 plus UA.Conclusion UA inhibits COX-2 expression in gastric cancer cells , which may be medi-ated through ROS/AMPK/STAT3 signal transduction pathway .

Objective To investigate the value of detecting methylated SEPT9 gene (mSEPT9) in serum and stool in screening colorectal cancer in elderly people.Methods Subjects were divided into three groups, the colorectal cancer group (n=82), the colorectal polyps group (n=80) and the healthy control group (n=100).Real-time quantitative polymerase chain reaction (PCR) was used to detect mSEPT9 in peripheral blood and feces.The relationship between mSEPT9 and clinical and pathological characteristics of colorectal cancer was analyzed.The agreement between serum and stool results was analyzed.Results The positive rate of serum mSEPT9 was 73.2％ in the colorectal cancer group, 6.3％ in the colorectal polyps group and 4.0％ in the healthy control group, with statistical significance between the colorectal cancer group and the other two groups (P＜0.01).The sensitivity and specificity for plasma mSEPT9 detection in screening colorectal cancer were 73.2 ％ and 95.6％, respectively.The positive rate was higher in patients with tumor maximum diameter over 3.0 cm, invasion of the entire serosa layer, lower differentiation or advanced clinical staging (P＜0.05).The detection results of plasma mSEPT9 were in complete agreement with those of stool mSEPT9 from the same patients.Conclusions The expression of mSEPT9 is high in elderly patients with colorectal cancer and has a high sensitivity and specificity for PCR detection.Complete agreement can be seen in results from plasma and feces.Detecting mSEPT9 can be a valuable approach to screening colorectal cancer in the elderly.

BacKground:The deveIopment of acute pancreatitis( AP ) is often accompanied by pancreatic microcircuIation disturbance and aIterations in bIood coaguIation and fibrinoIytic systems, which resuIts in abnormaIities of pIateIet parameters. Aims:To investigate the changes of pIateIet parameters in eIderIy AP patients and the effect of uIinastatin ( UTI)on pIateIet parameters and disease status. Methods:Two hundred and seventeen eIderIy AP patients(≥60 years) were enroIIed retrospectiveIy from Aug. 2009 to Dec. 2013 at the First AffiIiated HospitaI of Nanjing MedicaI University. According to the severity of the disease,patients were divided into three groups:miId AP( MAP),moderateIy severe AP ( MSAP),and severe AP( SAP). The pIateIet parameters,incIuding PLT,MPV and PDW before and after treatment,as weII as the differences in pIateIet parameters and cIinicaI efficacy between conventionaI therapy and UTI therapy were compared and anaIyzed. Results:In MSAP and SAP groups,PLT at admission was significantIy Iower(P<0. 01),whiIe MPV and PDW were significantIy higher(P<0. 05)than those in MAP group. After 1-week treatment,PLT increased significantIy(P<0. 01)and MPV and PDW decreased significantIy(P<0. 05)in MSAP and SAP groups. UTI therapy was superior to conventionaI therapy in increasing PLT( P <0. 01 ),decreasing MPV and PDW( P <0. 01 ),and improving the overaII efficacy in MSAP and SAP groups( MSAP:92. 3% vs. 81. 2%,P <0. 01;SAP:90. 0% vs. 80. 8%,P<0. 01). Conclusions:Changes of pIateIet parameters in eIderIy MSAP and SAP patients are different from those in MAP patients,which might refIect the disease severity. UTI is effective in reducing the activity of pIateIet and can be used in the treatment and prevention of disease progression in eIderIy AP patients.