Xanthomonas campestris NK-01 produces amounts of xanthan polysaccharide. Nonmucoid mutants, defective in synthesis of xanthan polysaccharide, were isolate after treatment with ethylmethanesulfonate. To isolate genes essential for xanthan polysaccharide synthesis complete libraries of DNA fragments from wild-type Xanthomonas campestris NK-01 were constructed in E. coli HB101. The pooled clone bank was conjugated en masse from E. coli into a nonmucoid mutant. Kanamycin-resistant exconjugants were then screened for the ability to form mucoid colonies. Analysis plasmids form muciod exconjugants indicated that overlapping segments of DNA had been cloned. These plasmids were tested for complementation of nine additional nonmucoid mutants. A 13. 4 kb region of DNA was determined to contain at least some genes essential for xanthan polysacchdride synthesis.

Objective To study the apoptosis in human gastric cancer cell BGC-823 induced by the components in serum of Banxia Xiexin prescription and different herbal fomulation. Method multiplication of cell BGC-823 was observed with MTT method. The genic expression of bcl-2 was tested by S-P immunohistochemistry tehnique. Results As for inhibition of cell BGC-823 multiplication, the groups of Xinkai, Kujiang and Xinku in Banxia Xiexin prescription and different herbal fomulation was dose-dependent and more sensitive than the groups of Xingan, Kugan, Ganbu and the intact prescription (P

Objective To investigate the epidemiological and etiological characteristics of foodborne diseases in Shiyan City, and to provide targeted measures for the prevention and control of foodborne diseases. Methods The surveillance data of foodborne diseases reported by Taihe Hospital of Shiyan City from 2013 to 2018 was collected and analyzed. Results A total of 1 742 cases of foodborne diseases were analyzed. The incidence peaked twice during the year, May to August and October to November. The pre-school children (≤6 years old) were at the highest risk of contracting foodborne diseases, and were mainly those in kindergartens, as well as those not in school. Grain and grain products accounted for the highest proportion of the presumably exposed foods． The main location of eating contaminated foods was in households. A total of 1 217 samples were tested, and 92 were positive, of which 71 strains were detected with Salmonella, accounting for the highest proportion. Preschool children and the elderly (≥66 years old) had higher detection rates than others. The food of infants and young children was found to have the highest detection rate. Conclusion According to the epidemiology and etiological characteristics of foodborne diseases in Shiyan City, the publicity and education of food safety should be strengthened and the surveillance network system of foodborne diseases should be further improved.

Cerebral hyperperfusion syndrome is a rare but potentially serious complication of cerebral revascularization,which occurs as a result of postoperative refractory hypertension and impaired cerebrovascular autoregulation. Cerebral hyperperfusion after balloon dilatation is prone to occur within the blood supply area of the offending vessel,rarely outside the offending vessel's supply area. This article presented a case of cerebral hyperperfusion syndrome outside the area treated with endovascular surgery.

Objective To compare the detection effects of Legionella pneumophila in water samples from public places by the Legiolert enzyme-substrate method and the conventional cultivation. Methods The Legiolert enzyme-substrate method and the conventional cultivation method were used to detect Legionella pneumophila in cooling water and shower water samples collected in public places. Isolated strains were verified and serotyped. Results A total of 68 samples were collected and tested. The positive rate of the conventional cultivation and the Legiolert enzyme-substrate method were 5.88%（4/68）and 35.29%（24/68）, respectively, with a significant difference （χ²=16.41，P<0.01）. The coincidence rate of the two methods was 64.71% (44/68), and the difference of the detection effects of the two methods was statistically significant (χ²=16.41，P=0.000). A total of 25 strains of Legionella pneumophila were isolated，and the serum types were mainly LP1（14/25）. Conclusion The Legiolert enzyme-substrate method represente a higher detection rate of Legionella pneumophila in water samples from public places than the conventional cultivation.

Objective To realize the epidemiological and pathogenic characteristics of foodborne illness in Shiyan in 2019 and provide targeted measures for the prevention and control work of the foodborne illness． Methods The active surveillance data of foodborne illness in shiyan in 2019 were collected and analyzed. The Salmonella strains isolated from the patients with foodborne illness were tested with serotyping，PFGE molecular classification and drug sensitivity test respectively according to《National foodborne illness surveillance workbook 2019》. Result A total of 3 191 cases of foodborne illness were analyzed. The pre-school children were the highest-risk group of foodborne diseases. Grain and grain product was the main suspicious contaminated food．The main location of eating place was family. A total of 330 samples were tested. The positive detection rate of foodborne illness was 20.30%（73/330）.The main pathogen were Rotavirus and Salmonella,and the detection rates were 11.21%(37/330) and 4.85%(16/330) respectively. The pre-school children were the group with the highest detection rate, which was 57.27% (63/110). The dominant serotype of the 14 Salmonella strains isolated from patients were Salmonella typhimurium and Salmonella enteritis. 14 different genotypes were obtained through PFGE classification and clustering. 64.29% (9/14) of Salmonella strains were multidrug-resistant strains. The drug resistance rates of ampicillin and tetracycline were the highest, which were 71.43%（11/14）and 64.29%（10/14）respectively. Conclusions The publicity and education of food safety should be strengthened and the surveillance network system of food-borne disease should be further improved according to the epidemiological and pathogenic characteristics of foodborne illness in Shiyan in 2019, and the use of clinical antibiotics should be controlled reasonably as well.

【Objective】 To analyze the independent influencing factors of repeated extracorporeal shock wave lithotripsy (ESWL) in the treatment of upper urinary calculi (UUC), based on which a nomogram model was established to predict the efficacy. 【Methods】 Clinical and imaging data of 203 patients receiving repeated ESWL during Jan.2020 and Dec.2022 were collected, including 117 cases in the successful group and 86 cases in the unsuccessful group.The patients’ age and sex, stone volume (SV), surface area (SA), skin-to-site distance (SSD), maximum CT value, mean stone density (MSD), and stone heterogeneity index (SHI) were compared between the two groups.The independent predictors were analyzed with logistic regression and the meaningful variables (P<0.05) were used to establish a nomogram.The efficacy of the model was evaluated using receiver operating characteristic (ROC) curve and decreasing curve analysis (DCA).Internal validation was also performed. 【Results】 Stepwise regression showed that SV, SSD, MSD and SHI were independent influencing factors (P<0.05).The area under the ROC curve (AUC), optimal threshold, sensitivity and specificity were 0.793 (95%CI: 0.674-0.911), 0.619, 77.1% and 74.0%, respectively.The DCA curve was above two extreme curves.Hosmer-Lemeshow test and calibration curve showed that the nomogram had a good fitting degree (χ²=5.526, P=0.489), and the correction C-index was 0.746. 【Conclusion】 SV, SSD, MSD and SHI are independent predictors of the efficacy of repeated ESWL in the treatment of UUC.The nomogram established based on the above indicators has good predictive efficiency and clinical applicability.

Objective: To investigate the influence of individual factors and labor organization on the prevalence of neck pain (hereinafter referred to as neck pain) in automotive assemblers, and to provide a basis for enterprises to optimize neck pain interventions. Methods: A cluster random sampling method was taken in January 2021, at an automobile manufacturing plant in Shiyan, 656 assemblers with ≥1.0 years of service were selected, the "Musculoskeletal Disorder Questionnaire" was used to investigate the incidence and influencing factors of neck pain. Pearson χ(2) test or trend χ(2) test was used to compare the data rates. The influencing factors of neck pain were analyzed by multivariate logistic regression. Results: The prevalence rate of neck pain (hereinafter referred to as the prevalence rate of neck pain) of automobile assemblers within one year was 53.94% (342/634) . The prevalence of neck pain in women was higher than that in men (69.1% vs 48.6%, P<0.01) . The prevalence of neck pain was related to length of service, self-assessment of fatigue, working hours per week, working in the same workshop, rest days per shift, and accumulated rest time per shift (P<0.05) . Multivariate logistic regression analysis showed that the risk of neck pain in women was 2.434 times higher than that in men; The risk of neck pain increased by 18.9% for each hour of work per week; Rest during work was a protective factor for neck pain. The number of rest per shift increased and the risk of neck pain decreased (r=0.405, 0.311, 0.302, 95%CI=0.205~0.803, 0.169~0.572, 0.142~0.642, P<0.05) . Conclusion: The annual prevalence of neck pain was higher in automobile assemblers. Enterprises should fully consider the influencing factors such as gender, working hours per week and the number of breaks when arranging production.
Female ; Humans ; Male ; Musculoskeletal Diseases/epidemiology* ; Neck Pain/epidemiology* ; Occupational Diseases/epidemiology* ; Prevalence ; Risk Factors ; Surveys and Questionnaires

Objective To investigate the influence of individual factors and labor organization factors on work-related musculoskeletal disorders (WMSDs) in automobile manufacturing workers, and to provide a scientific basis for the prevention and treatment of WMSDs in automobile manufacturing workers. Methods In April 2020, 5564 workers in an automobile factory were selected by cluster sampling method. The prevalence of WMSDs was investigated by using the Musculoskeletal Disorders Questionnaire, and the influence of individual factors and labor organization factors on WMSDs was investigated by using generalized estimation equation. Results The prevalence rate of WMSDs was 79.00% (4396/5564), and the prevalence rate of multisite WMSDs was 67.95% (3781/5564). The analysis of generalized estimation equation showed that doing the same job every day (OR= 1.478, P < 0.05), age ≥40 years (OR=1.416, P< 0.05), personnel shortage (OR= 1.356, P < 0.05), and work length of 6～10 years and 11～15 years (OR= 1.349, P< 0.05) were the main risk factors for WMSDs in automobile manufacturing workers. Shift work and working time > 40 hours per week increased the risk of WMSDs (P< 0.05). Male and adequate rest time were protective factors for WMSDs. The job correlation matrix showed that WMSDs in most parts had a positive correlation. Conclusions The prevalence of multisite WMSDs of workers in automobile manufacturing industry is high, and unreasonable labor organization is the main risk factor of WMSDs. Appropriate work breaks can effectively reduce the risk of WMSDs, and effective intervention measures should be carried out to prevent the occurrence of WMSDs in workers in automobile manufacturing industry. The generalized estimation equation can better analyze the influencing factors of WMSDs.

This study plans to prepare lipid bilayer-coated mesoporous silica nanoparticles (LMSNs) which are pH sensitive with core-shell structure to improve the tumor cell lethality of antitumor drug. The lipid coated mesoporous silica nanoparticles loaded with irinotecan (CPT-11) (CPT-11-LMSNs) were prepared by hot water-film hydration method, and the characterized its morphology, particle size and release in vitro. Meanwhile, the intracellular uptake and cell toxicity of CPT-11-LMSNs and intracellular accumulation of CPT-11 were evaluated on human breast carcinoma cell line (MCF-7). The results indicated that the mean diameter of the spherical LMSNs was (120.27 +/- 5.91) nm. The slow release in simulated normal physiological conditions and a rapid release under simulated intracellular condition demonstrated the pH sensitivity of CPT-11-MSNs in vitro. Moreover, the CPT-11-LMSN could improve the intracellular CPT-11 cumulant 2.1 times and reduce half maximal inhibitory concentration (IC50) values of CPT-11 1.4 times compared with CPT-11-MSNs, demonstrating a stronger cell lethality.