Background Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen for both human bloodstream infections and mastitis in cows. However, little attention has been paid to the cross-host transmission of MRSA from cows to high-risk groups in China. Objective To determine the MRSA colonization rates among dairy cows and dairy farm workers in Xinjiang, identify the antibiotic resistance profiles and molecular characteristics of the isolates, and provide scientific evidence for the formulation of targeted infection control strategies. Method A cross-sectional survey combined with laboratory pathogen analysis was conducted. From June to August 2024, large-scale dairy farms in Xinjiang region were selected as study sites. Nasal swabs (n=96) and skin swabs (n=39) were collected from workers, and bovine nasal swab samples (n=109) were collected simultaneously. All samples were subjected to MRSA isolation, cultivation, and identification, followed by antibiotic susceptibility testing to characterize resistance phenotypes. Staphylococcus aureus protein A (Spa) typing was performed to determine strain genotypes and elucidate MRSA colonization rates and molecular epidemiological patterns. Results A total of 35 MRSA strains was successfully isolated from 244 samples. The MRSA colonization rates among dairy farm workers and dairy cows were 20.83% (20/96) and 12.84% (14/109), respectively, with an overall isolation rate of 14.34% (35/244). Among the workers, the nasal colonization rate was 16.67% (16/96), and the skin colonization rate was 12.82% (5/39). One worker exhibited MRSA colonization at multiple body sites. All MRSA strains were resistant to cefoxitin (100%, 35/35). The resistance rates to erythromycin and clindamycin were 42.86% (15/35) and 34.29% (12/35), respectively. Thirteen strains showed a multidrug-resistant phenotype, whereas all strains were susceptible to vancomycin. The MRSA isolates exhibited high genetic diversity, with 13 Spa types identified, among which t441 was the most prevalent (8 strains). Both t441 and t034 types were detected in samples from both the dairy cows and their handlers. These two Spa types also carried and stably inherited specific resistance combinations, including erythromycin–clindamycin–cefoxitin and ciprofloxacin–erythromycin–clindamycin–gentamicin–cefoxitin–tetracycline, and a statistically significant association was also observed between the two resistance profiles and the bacterial types (P < 0.001). In addition, one novel Spa type strain was identified. Conclusion MRSA colonization rates among dairy cows and dairy farm workers in Xinjiang are relatively high, with evidence of multi-site colonization. The isolates exhibit high levels of multidrug resistance and genetic diversity, indicating a potential risk of cross-host transmission.

Objective To compare the clinical outcomes of subxiphoid robot-assisted thoracoscopic surgery (SRATS) and intercostal robot-assisted thoracoscopic surgery (IRATS) in the treatment of anterior mediastinal tumors. Methods A retrospective analysis was conducted on patients with anterior mediastinal tumors who underwent robot-assisted surgery in the Department of Thoracic Surgery, Gansu Provincial Hospital, from May 2020 to July 2022. According to the surgical approach, patients were divided into an SRATS group and an IRATS group. Perioperative data were compared between the two groups. Results A total of 87 patients were included. There were 41 patients in the SRATS group [23 males, 18 females; mean age, (44.51±11.28) years] and 46 patients in the IRATS group [21 males, 25 females; mean age, (46.67±8.76) years]. Compared with the IRATS group, the SRATS group had significantly less intraoperative blood loss [(24.41±6.67) mL vs. (37.93±9.23) mL, P<0.001], shorter postoperative drainage duration [(1.73±0.59) days vs. (2.54±0.50) days, P<0.001], lower postoperative drainage volume [(94.46±34.08) mLvs. (116.72±24.90) mL, P=0.001], lower visual analogue scale (VAS) pain scores on postoperative day 1 [(3.66±0.76) points vs. (4.15±0.84) points, P=0.005] and day 3 [(2.41±0.59) points vs. (2.89±0.82) points, P=0.003], shorter postoperative hospital stay [(4.12±0.81) days vs. (4.98±1.02) days, P<0.001], and lower hospitalization costs [(4.51±0.65) ten thousand yuan vs. (4.86±0.68) ten thousand yuan, P=0.020]. There were no statistical differences between the two groups in operative time or incidence of postoperative complications (P>0.05). Conclusion Both SRATS and IRATS are safe and effective for the treatment of anterior mediastinal tumors. However, SRATS is less invasive and more conducive to enhanced postoperative recovery.

Objective To evaluate the ability of longitudinal changes in urinary extracellular domain of neurotrophin receptor p75(p75ECD)to serve as a prognostic biomarker of severity,progression and survival time in patients with amyotrophic lateral sclerosis(ALS).Methods Forty patients with ALS attended follow-up appointments at 3-to 6-month interval,and 51 healthy control(HC)volunteers were recruited.The concentrations of urinary p75ECD were tested by a sandwich ELISA.The ALSFRS-r was used to quantify the severity of ALS.The change rate of urinary p75ECD(Δp75ECD)was calculated as the average monthly change during the period between the first and the last sampling.Results The concentration of urinary p75ECD was higher at the last follow-up than at baseline(P=0.002 3).Spearman analysis showed that there was a negative correlation between urinary p75ECD and ALSFRS-r score(r=-0.35,P=0.001 3);the course of ALS in the fast-changing Δp75ECD group was shorter than that in the slow-changing group(P=0.015 8);the Δp75ECD and course of ALS showed a negative correlation(r=-0.39,P=0.014),and the Δp75ECD in the fast-progression ALS group was significantly higher than in the slow-progression group(P=0.001 6).There was a positive correlation between Δp75ECD and progression in ALS patients(r=0.34,P=0.005).Kaplan-Meier survival analysis showed a longer median survival time in those with slow-changing Δp75ECD(P=0.03).Conclusion The change rate of urinary p75ECD has shown great potential as a biomarker for the prognosis of the severity,progression and survival time of ALS.

Objective To explore the value of support vector machine(SVM)model based on gray matter volume(GMV)for identifying amyotrophic lateral sclerosis(ALS),also to analyze the relevant brain regions.Methods MR 3D T1WI data of 60 ALS patients(ALS group)and 60 healthy volunteers(control group)were retrospectively analyzed.Taken GMV of each brain region obtained by voxel-based morphometry as the input features.F-score analysis was used to select feature with the highest classification accuracy to construct SVM model.Receiver operating characteristic curve was drawn to evaluate the efficacy of SVM model for identifying ALS,and top 10％was used as the weight threshold to obtain gray matter brain regions contributed the most to this model.Results SVM model constructed based on the top 40％GMV features had the highest classification accuracy(82.50％),with sensitivity,specificity and area under the curve(AUG)of 85.05％,80.40％and 0.890,respectively.The left precentral gyrus,left anterior cingulate gyrus and paracingulate gyrus,right middle temporal gyrus,opercular part of left inferior frontal gyrus,right dorsolateral superior frontal gyrus,left temporal pole:middle temporal gyrus,right superior occipital gyrus,orbital part of right middle frontal gyrus,right calcarine fissure and surrounding cortex,right fusiform gyrus were the top 1-10 gray matter brain regions contributed to this model.Conclusion ALS had specific GMV change pattern.SVM model based on GMV could be used to effectively identify ALS,while the left precentral gyrus was the most contributive brain region to this model.

Objective By comparing the prevalence and mortality of dementia among rural people in Xi'an in 1997 and 2014 to clarify the epidemiological changes of dementia among rural people in the city over 17 years.Methods In 1997 and 2014,people aged 55 and above in villages in Xi'an were selected by random cluster sampling method,and face-to-face questionnaire survey was conducted by combining centralized and home visits.Dementia and its subtypes were diagnosed by"the three-step method";the changes of dementia prevalence and mortality were compared between the two surveys.Results The prevalence of dementia among rural residents aged 55 and above in Xi'an was 3.49％in 1997,with age-gender standardized prevalence of 2.08％.In 2014,the prevalence of dementia was 4.25％,with age-gender standardized prevalence of 2.78％.Over the 17 years,the prevalence of dementia increased by 1.79 times(OR=1.79,95％CI:1.20-2.65,P=0.004),with a 1.9-fold increase in females and a 1.67-fold increase in males.The mortality of dementia patients was 61.76‰ and age-gender standardized mortality was 60.20‰ in 1997,while the mortality was 35.71‰ and age-gender standardized mortality was 34.18‰ in 2014.The mortality of dementia decreased by 33％over the 17 years(HR=0.33,95％CI:0.15-0.74,P=0.007).Conclusion The prevalence of dementia in rural areas of Xi'an increased significantly over the 17 years,but the mortality rate decreased,and this trend was more obvious in women.

Objective To investigate the relationship between baseline serum lipid levels and cognitive decline after a 4-year follow-up in a cohort of middle-aged and elderly people in rural Xi'an.Methods The data were collected from the cognitive impairment cohort of middle-aged and elderly people in rural areas of Xi'an,Shaanxi Province.The cohort selected the population ≥40 years old in two villages of Huyi District,Xi'an,as the research subjects.The baseline survey was completed from October 2014 to March 2015,and two follow-up visits were conducted in 2016 and 2018.The Mini-Mental State Examination(MMSE)was applied to assess the overall cognitive function.The MMSE score dropping between the 2014 and 2018(△MMSE)≥2 points were defined as cognitive decline.Baseline lipid levels[total cholesterol(TC),triglyceride(TG),high-density lipoprotein cholesterol(HDL-c),low-density lipoprotein cholesterol(LDL-c)]were converted into three classification data based on 25％quantile and 75％quantile[Q1(≤25％)vs.Q2-Q3(25％-75％)vs.Q4(≥75％)],and using the Q2-Q3 group as the reference group.The relationship between serum lipid levels and cognitive decline at baseline was analyzed by multivariate Logistic regression.Interaction effect analysis and subgroup analysis were made to investigate the interaction effect of age(＜65 years vs.≥65 years)on the relationship between serum lipid and cognitive decline.Results There were 1 349 participants with complete baseline data,and 235(17.42％)were ≥65 years old at baseline;230 cases(17.05％)had cognitive decline.No significant association was found between TC,TG,LDL-c,HDL-c and cognitive decline in subgroups＜65 years of age.In the subgroup ≥65 years of age,the Q1(≤4.37 mmol/L)group of TC was not significantly associated with the risk of cognitive decline compared with the Q2-Q3(4.37-5.61 mmol/L)group of TC,but the Q,(≥5.61 mmol/L)group of TC was significantly associated withan increased risk of cognitive decline(OR=2.519,95％CI:1.217-5.214,P=0.013).Age had an interactive effect on the relationship between the Q4 group of TC and cognitive decline(OR=2.202,95％CI:1.111-4.363,P=0.024).Compared with the Q2-Q3(1.03-2.01 mmol/L)group of TG,the Q,(≤ 1.03 mmol/L)group of TG was associated with a lower risk of cognitive decline(OR=0.318,95％CI:0.120-0.838,P=0.020).Age had an interactive effect on the relationship between the Q1 group of TG and cognitive decline(OR=0.344,95％CI:0.132-0.896,P=0.029).However,there was no significant correlation between the Q4(≥2.01 mmol/L)group of TG and the risk of cognitive decline.Compared with the Q2-Q3(2.70-3.81 mmol/L)group of LDL-c,the Q1(≤ 2.70 mmol/L)group of LDL-c was not significantly associated with the risk of cognitive decline,but the Q4(≥3.81 mmol/L)group of LDL-c had significant association with an increased risk of cognitive decline(OR=2.367,95％CI:1.143-4.900,P=0.020).Age had an interactive effect on the relationship between the Q4 group of LDL-c and cognitive decline(OR=2.237,95％CI:1.134-4.415,P=0.020).No significant association was found between HDL-c and cognitive decline.Conclusion No significant association was found between HDL-c and cognitive decline at baseline.The relationship of TC,TG and LDL-c with cognitive decline was affected by age.Only in participants over 65 years old,the risk of cognitive decline was higher in those with high baseline levels of TC and LDL-c.Those with low baseline serum TG levels had a lower risk of cognitive decline.

Objective To investigate the relationship between type 2 diabetes mellitus(T2DM)and cognitive decline.Methods Data were obtained from the cognitive impairment cohort of middle-aged and elderly population in rural areas of Xi'an City.The cohort consisted of residents aged 40 years and older in two villages of Huyi District,Xi'an.The baseline survey was completed between October 2014 and March 2015,with two follow-up visits in 2016 and 2018.The present study was conducted on cognitively normal people at baseline.Individual characteristics,lifestyle,and medical history were collected;physical and biochemical examinations were completed.According to medical history of T2DM and fasting blood glucose,the study population was divided into non-T2DM group,pre-existing T2DM group,and new-onset T2DM group.The Mini-Mental State Examination(MMSE)was used to assess global cognitive function.Participants with a drop of≥2 points in MMSE score from baseline after 4 years were defined as having cognitive decline.Chi-square test and multivariate Logistic regression analysis were employed to analyze the effect of T2DM status on the risk of cognitive decline.Results A total of 1 350 subjects completed the follow-up.In the follow-up population,1 096(81.2％)were free of T2DM,158(11.7％)already had T2DM at baseline,and 96(7.1％)developed new-onset T2DM during the follow-up.Cognitive decline was observed in 230 individuals after 4 years,representing 17.0％of the study population.The new-onset T2DM group had the highest 4-year incidence of cognitive decline(non-T2DM group vs.pre-existing T2DM group vs.new-onset T2DM group:15.7％vs.20.9％vs.26.0％,P=0.014),and the incidence of cognitive decline in the newly-onset T2DM group was significantly higher than that in the non-T2DM group(P=0.009).Multivariate Logistic regression analysis showed that the new-onset T2DM group had an increased risk of cognitive decline compared with the non-T2DM group within 4 years(OR=1.726,95％CI:1.029-2.896,P=0.039).However,no significant difference in 4-year risk of cognitive decline in the pre-existing T2DM group was observed(OR=1.402,95％CI:0.890-2.210,P=0.145).Conclusion Through the 4-year follow-up study of cognitively normal adults aged 40 and above in rural Xi'an,it was found that new-onset T2DM patients face a significantly elevated risk of cognitive decline,suggesting that cognitive decline may occur in the early stage of T2DM.

Objective To explore the relationship between plasma amyloid-β(Aβ)and cognitive impairment.Methods A total of all villagers(aged 40 years and above)from two villages of Xi'an,China,were enrolled.A validated Chinese version of the Mini-Mental State Examination and neuropsychological battery were used to assess cognition.Levels of fasting plasma Aβ1-42 and Aβ1-40 were tested using commercial enzyme-linked immunosorbent assay(ELISA).Relationship between plasma Aβ and cognitive impairment was analyzed using Logistic regression analysis.Results Of the 1 314 enrolled subjects,1 180(89.80％)had normal cognition,85(6.47％)had suspected cognitive impairment,and 49(3.73％)had probable cognitive impairment.Univariate analysis showed that plasma Aβ1-42/Aβ1-40 ratio was higher in the suspected cognitive impairment group than in the probable cognitive impairment group(P＜0.05)and normal cognitive group(P＜0.05);plasma Aβ1-42 level in the suspected cognitive impairment group was higher than that in normal cognitive group(P＜0.05).The level of Aβ1-40 did not differ between the three groups.After correcting for confounding factors(including age,gender,degree of education,cognitive impairment risk factors,habits of living)in the multivariate Logistic regression analysis,the results were consistent with those in the univariate analysis.Conclusion Levels of plasma Aβ1-42 and Aβ1-42/Aβ1-40 ratio were elevated in patients with suspected cognitive impairment,indicating that elevated plasma Aβ1-42 and Aβ1-42/Aβ1-40 ratio may be more pronounced in early stage of cognitive impairment.They may be early biomarkers for cognitive impairment,which can help identify and intervene the disease earlier.

Objective To investigate the relationship between plasma homocysteine(Hcy)levels and cognitive impairment(CI).Methods From November 2018 to January 2019,baseline data and cognitive function were collected from the participants aged≥40 years who lived in two villages in Huyi District,Xi'an,China.Their global cognitive function was assessed by Mini-Mental State Examination(MMSE)and the diagnosis of cognitive impairment was based on international guidelines.Fasting blood was collected in the morning,and plasma Hcy level was measured by the chemiluminometric assay.Multivariate Logistic regression analysis,subgroup analysis,and interaction analysis were performed to investigate the relationship between plasma Hcy and CI.Results A total of 1 805 subjects were included in the analysis.There were 1 056 females(58.5％),age ranged from 40 to 88 years[mean(58.99±9.52)years],and 145 participants(8.0％)were diagnosed as CI.The median plasma Hcy level in the overall population was 14.1(11.6,17.8)μmol/L.There were 729(40.4％)subjects in the HHcy group(＞15.0 μmol/L)and 1 076(59.6％)in the normal group(≤15.0 μmol/L).Univariate analysis showed that the prevalence of CI was higher in the HHcy group than in the normal Hcy group(11.4％vs.5.8％,P＜0.001).In multivariable Logistic regression fully adjusted for potential confounders,each 1 μmol/L increase in plasma Hcy level was associated with a 3.0％increased risk of CI(OR=1.030,95％CI:1.012-1.048,P=0.001).Interaction analysis indicated that sex,age,BMI,systolic blood pressure,history of stroke,and diabetes did not significantly modify this association.Conclusion Elevated plasma Hcy levels are associated with an increased risk of CI in people aged≥40 years.This indicates that HHcy may be a risk factor for CI.

Objective To explore the relationship between carotid atherosclerosis(CAS)and cognitive impairment in the stroke high-risk population aged 40 years and above in the rural area of Xi'an City and determine whether CAS is a risk factor for cognitive impairment.Methods In this study,stroke high-risk population found in the Community and Rural Population Stroke High-risk Group Screening and Intervention Project carried out in Huyi District,Xi'an City,from October 2014 to March 2015 were selected as the research subjects.Color Doppler ultrasound was used to evaluate CAS,and CAS was defined as:carotid intima-media thickness(CIMT)≥1.0 mm,or carotid arteries(including common carotid artery,carotid sinus,internal carotid artery,and external carotid artery)have atherosclerotic plaques,or carotid stenosis.Mini-Mental State Examination(MMSE)was used to assess cognitive function.The MMSE score lower than the cut-off value(illiteracy ≤17,primary school ≤ 20 points,and junior high school and above education level ≤24 points)is defined as cognitive impairment.The study population was grouped according to the presence of CAS or cognitive impairment;univariate difference test and bivariate logistic regression were used to analyze the relationship between CAS and cognitive impairment.Results A total of 451 subjects were included in the analysis.The average age of the subjects was(58.7±9.83)years old,and 44.3％were female.Among them,329 cases(72.9％)had CAS and 57 cases(12.6％)met the diagnostic criteria for cognitive impairment.The prevalence of cognitive impairment in CAS group was significantly higher than that in non-CAS group(14.6％vs.7.4％,P=0.041).Multivariate logistic regression analysis showed that cognitive impairment was significantly correlated with age(OR=1.121,95％CI:1.056-1.189,P＜0.001),but not with CAS(OR=1.008,95％CI:0.202-5.170,P=0.992).Conclusion No significant association between CAS and cognitive impairment was found in high stroke risk group aged 40 and above in rural areas of Xi'an.