Objective To explore the in vivo killing effects of nanosecond pulsed electric fields on mouse breast cancer in tumor bearing BALB/c mice. Methods Twenty four BALB/c mice models with subcutaneous EMT-6 breast cancer were prepared and divided into experimental group and control group (n=12). In experimental group, the mice were treated by the pulsed electric fields with peak voltage of 700 V/cm, rise times of 57 ns, durations of 70μs and duty ratio of 50%on the tumor tissue with two parallel electrodes under anaesthesia. One hundred pulses were given and the energy was just 9.75 J with effective action period of 7 ms. Tumor volume, animal weight and histopathologic changes after 1, 3, 5 and 7 d were observed after irreversible electroporation. Results The tumor volume in experimental group increased more slowly than that in control group, especially at the 1-3 d after treatment with a standstill. Histopathological examination results showed that the tumor tissue had obvious coagulation necrosis and tissue edema after electrical stimulation treatment, and mass vacuole like structure appeared in tumor tissue from the third day after treatment and vascular injury occurred at the early stage. Conclusions In the given field conditions, steep pulsed electric field has inhibitory effect on tumor growth. In order to achieve more ideal tumor therapy effect, further studies on steep pulse dose are needed.

Objective: To investigate the antimicrobial resistance in and multilocus sequence typing (MLST) of Campylobacter jejuni in meat and meat products in Liaoning Province, so as to provide insights into the management of C. jejuni infection. Methods: Nine C. jejuni isolates from meat and meat products in 2020 were subjected to whole genome sequencing, and the minimum inhibitory concentration was measured with the agar dilution method. MLST of C. jejuni isolates was performed with the microbial resistance mechanism traceability reference database and analysis system. Results: Six drug-resistant C. jejuni isolates were detected, and there were four multidrug-resistant isolates. There were six C. jejuni isolates resistant to tetracycline, five isolates resistant to nalidixic acid, four isolates resistant to ciprofloxacin, two isolates resistant to florfenicol, one isolate resistant to gentamicin and one isolate resistant to streptomycin. Nine C. jejuni isolates showed sensitive to azithromycin, chloramphenicol and clindamycin. MLST identified six ST types in nine C. jejuni isolates, with ST45 and ST2274 as the predominant type, and detected one isolate with unclassified ST type. Phylogenetic analysis showed that KW028 and KW029 of ST45 type were closely related and had high homology, and KW040 and KW042 of ST2274 type were closely related with high homology, while KW007 of ST6701 type was closely related to KW040 and KW042 of ST2274 type, with only one pgm housekeeper gene in difference. Conclusions High resistance to tetracycline, nalidixic acid and ciprofloxacin was detected in nine C. jejuni isolates from meat and meat products, and ST45 and ST2274 were predominant ST types of C. jejuni.

Objective To establish a bioiflm (BF) models of Haemophilus inlfuenza in vitro, and to observe the changes of antibiotic susceptibility after the BF fromation. Methods Thirty strains Haemophilus inlfuenzae isolated from adenoids of children with adenoidal hypertrophy and cultured in a 96-well plate. The BF was identiifed by crystal violet staining and scanning electron microscopy (SEM). The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and the minimum bioiflm bacteria bioiflm clear concentration (MBEC) of ampicillin (AMP), ceftriaxone (CRO), levolfoxacin (LVFX) and azithromycin (AZM) were individually detected. Result All of 30 strains of Haemophilus inlfuenzae formed various BF. After BF is formed, the increase of MBEC for different antibiotics was inconsistent with the increase of MIC and MBC. The difference was statistically signiifcant (MBEC/MBC, H=91.54;MBEC/MIC, H=87.91;all P<0.001). The MBEC of AMP was the highest, up to 100 times than the MBC and MIC. The MBEC of CRO was dozens of times than the MBC and MIC. The MBEC of LVFX and AZM were most close to those of MBC and MIC. Conclusion After the formation of BF, resistance to antibiotics of Haemophilus inlfuenzae is enhaced. LVFX and AZM showed more favorable effect on Haemophilus infuenzae BF.

Objective To investigate the expressions of Livin and vascular endothelial growth factor (VEGF)in pancreatic carcinoma and their cilinical significances.Methods The expressions of Livin and VEGF proteins were tested by immunohistochemistry in 68 cases of pancreatic carcinomas and 44 cases of adja-cent paracancerous tissues.Results The positive rates of Livin in pancreatic carcinomas and adjacent paracan-cerous tissues were 73.5% and 4.5% respectively,and the difference was statistically significant (χ2 =48.137,P<0.001).The positive rates of VEGF in pancreatic carcinomas and adjacent paracancerous tissues were 69.1% and 13.6% respectively,and the difference was statistically significant (χ2 =29.147,P <0.001).The expressions of Livin and VEGF were related with tumor differentiation (χ2 =6.061,P=0.014;χ2 =6.592,P=0.010),TNMstage (χ2 =4.175,P=0.041;χ2 =9.992,P=0.002),lymph node metasta-sis (χ2 =11.731,P=0.001;χ2 =12.002,P=0.001)and neural invasion (χ2 =9.950,P=0.002;χ2 =7.433,P=0.006).Significantly positive correlation was found between the expressions of Livin and VEGF by using Spearman correlation analysis (r=0.320,P=0.008).Survival analysis showed that the expressions of Livin and VEGF were independent prognostic factors in pancreatic carcinoma.Conclusion Livin and VEGF involve in the development,migration and metastasis of pancreatic carcinoma.Livin may upregulate the expres-sion of VEGF,which may lead to the angiogenesis and migration in pancreatic carcinoma.

Objective To explore the killing effect of dielectric barrier discharge (DBD) plasma on tumor cells and to analyze the DBD-induced apoptosis mechanism.Methods Thiazolyl blue tetrazolium bromide (MTT) assay method was used to detect the killing effect of low temperature plasma on the cytotoxicity of normal spleen leukocytes and acute promyelocytic leukemia cells (LT-12) at different doses.The changes of reactive oxygen species (ROS) level were measured after plasma treatment.The cell apoptosis rate was detected by Annexin V/PI double staining at different doses.The expression of apoptosis-related genes and proteins was detected by qRT-PCR and Western Blot.Results MTT results showed that the killing effect of plasma treatment was dose-dependent and time-dependent.The cell survival rate after 8 hours of treatment decreased from 98％ to 63％ with the dose increasing from 30 s to 240 s.The survival rate decreased from 78％ (2 h) to 39％ (24 h) after the treatment with a same dose (e.g.240 s).Annexin V/PI double staining results demonstrated that the plasma effect can induce apoptosis,and the apoptosis rate was not only positively correlated with the plasma dose,but also with the post-plasma time.The longer the post-plasma time,the higher was the apoptosis rate.The apoptotic rate of the 60 s dose treatment after 12 h was 48％ that increased to 55.3％ with the dose of 120 s.The production of reactive oxygen species (ROS) detected by flow cytometry also showed a time correlation of the plasma treatment.After the plasma treatment,the ROS level immediately increased to 1.24 times,and sharply increased to 5.39 times after 20 h post-plasma.The experimental results of qRT-PCR and Western blot showed that the expression of the genes and proteins of Caspase family and Bcl-2 family was very active at 8 to 12 h post-plasma treatment.Conclusions Low-temperature plasma can effectively kill tumor cells,and apoptosis is the main mechanism of death.The molecular mechanism of apoptosis of tumor cells induced by low temperature plasma was preliminary confirmed.

Objective To evaluate the effects of flapless versus flap implant surgery on the tissues surrounding the implants in the esthetic zone.Methods A controlled study was conducted in 20 patients with a single implant in the anterior esthetic zone,as compared with the flapless and traditional flap implant placement.6 and 12 months after the implant ation,the vertical reduction of labial and lingual bone were assessed by cone beam computed tomography (CBCT);6 and 12 months after the crowns restoration,the peri-implant soft tissues were examined by probing depth (PD),modification sulcus bleeding index (mSBI),papillary index (PPI) and evaluated by pink esthetic score (PES) standard.Results The vertical reduction of the flapless labial and lingual bone was lower than that of the flap,in which the change of labial bone was statistical differences at 6 months after implant surgery between groups (P ＜ 0.05).The differences of PES between two groups were not statistically significant,although PES increased over time in both groups,which the flapless group had a significantly change in PES from crown placement to 12 months (P＜0.05).Conclusions A flapless implant surgery in sufficient bone support may provide a better short-term esthetic result,whereas the longterm effects need further studies.

Objective:To analyze the correlation between 21-gene recurrence score (RS) and clinicopathological characteristics of patients with Lumina type breast cancer, and to explore its significance in individualized treatment.Methods:The clinicopathological data of 59 patients with surgical resection and pathological diagnosis of Lumina type breast cancer in Shanxi Provincial Cancer Hospital from May 2018 to May 2019 were retrospectively analyzed. Real-time fluorescence quantitative polymerase chain reaction was used to detect the expression of 21 gene and RS was calculated. According to the 21-gene RS, the patients were divided into low recurrence risk group (RS < 18 points), intermediate recurrence risk group (RS 18-31 points) and high recurrence risk group (RS > 31 points). Univariate and multivariate logistic regression analyses were made to evaluate the correlations between different recurrence risk and clinicopathological characteristics of patients and their influence on the choice of adjuvant chemotherapy.Results:Based on the 21-gene RS, 29 patients were in low recurrence risk group, 22 cases were in intermediate recurrence risk group, and 8 cases were in high recurrence risk group. Single-factor analysis showed that age ( P = 0.012), maximum mass diameter ( P = 0.031), histological grade ( P = 0.036), progesterone receptor (PR) level ( P = 0.015), Ki-67 positive index ( P = 0.049) and molecular typing ( P = 0.010) were influencing factors of 21-gene RS recurrence risk. Multivariate logistic regression analysis showed that the age and Ki-67 positive index were negatively correlated with 21-gene RS recurrence risk (both P < 0.05). After grouping according to the 21-gene RS, 17 patients in the intermediate recurrence risk group (according to the traditional postoperative recurrence risk grouping method for breast cancer) were classified as low recurrence risk group, and 4 patients in the low recurrence risk group were classified as intermediate recurrence risk group ( χ2 = 4.535, P = 0.033). After grouping based on 21-gene RS, the number of patients who needed chemotherapy in individualized treatment decreased. Of the 17 cases, 11 cases did not undergo postoperative chemotherapy, and the remaining patients received chemotherapy. The postoperative follow-up period was 11-22 months. As of March 2020, there was no recurrence or disease progress. Conclusion:The 21-gene RS can provide objective basis for the individualized precise treatment and prognosis prediction for patients with early-stage Lumina type breast cancer.

Objective: To assess physical activity level and characteristics in elementary physical education (P.E.) class among different weight status and grades students. Methods: ActiGraphGT3X was used to measure physical activity of 60 students in grade 1, 2, and 4 during three P.E. classes. BMI was calculated according to the student s height and weight in the latest physical fitness test results, and the weight status was divided according to the national Physical Fitness Standards for Students in different grades of elementary schools. Independent sample t test and analysis of variance were used to explore the difference of physical activity. Results: The proportion of moderate to high intensity physical activity (MVPA) in elementary school P.E. class was 21.9% (8.8 min). The proportion of MVPA in P.E. classes and the number of steps in normal weight students were 25.4% and (1 247.0± 326.3 ), respectively, which were significantly higher than those of underweight students, but not significantly different from those of overweight students. The MVPA of male and female PE classes in the second grade (27.0%, 26.4%) was significantly higher than that in the first grade, but there was no significant difference compared with that in the fourth grade ( P >0.05). Conclusion Moderate to high intensity physical activity is low in P.E. class in elementary school. Improving teachers awareness of promoting physical activity in PE class will benefit the MVPA in students.

Background Job burnout has become an important factor affecting the mental and physical health and work efficiency of college counselors, and indirectly affects the quality and development of talent cultivation for college students. Objective To explore the relationship between job stress, job crafting, and job burnout among college counselors, and to test the mediating role of job crafting between job stress and job burnout, in order to take targeted measures to alleviate job stress and job burnout of college counselors, reduce associated health risks, and improve the effectiveness of higher education. Methods An anonymous questionnaire survey was conducted among 400 counselors from social network communication groups by convenience sampling. The Counselor Work Stress Scale, Job Crafting Scale, and Maslach Burnout Inventory-General Survey were used. Harman's single-factor method was used to evaluate common method bias in the survey data. One-way ANOVA was applied to test the difference in job stress, job crafting, and job burnout among college counselors by demographic characteristics, and chi-square test was used to analyze the difference in reporting job burnout. Partial correlation analysis was used to evaluate the correlation between selected variables. Structural equation modeling was used to analyze the relationship of job stress, job crafting, and job burnout among college counselors, and Bootstrap analysis was used to test if there was a mediating effect of job crafting on the relationship between job stress and job burnout. Results Of the 390 questionnaires recovered, there were 338 valid questionnaires (86.67%). Among the included subjects, the mean scores of job stress, job crafting, and job burnout were (2.70±0.62), (3.77±0.62), and (2.09±1.09), respectively. The positive rate of job burnout was 76.9% (260/338), with a positive rate of 72.8% in exhaustion dimension and 59.8% in cynicism dimension. There were significant differences in job crafting scores among the college counselors by different genders and professional titles (P<0.05). Female counselors had significantly higher job burnout scores and positive rates than male counselors (P<0.05). The partial correlation analysis showed that job stress, work load, school evaluation and expectation, and interpersonal relationship were positively correlated with job burnout (r=0.562, 0.442, 0.473, and 0.455, respectively, P<0.01), and negatively correlated with job crafting (r=−0.271, −0.169, −0.246, and −0.247, respectively, P<0.01); job crafting, cognitive crafting, relationship crafting, and task crafting were negatively correlated with job burnout (r=−0.447, −0.452, −0.366, and −0.340, respectively, P<0.01). The modified structural equation modeling indicated that job stress negatively affected job crafting (b=−0.348, P<0.001) and positively affected job burnout (b=0.454, P<0.001); job crafting negatively affected job burnout (b=−0.459, P<0.001), and played a partial mediating role in the relationship between job stress and job burnout, and the effect value was 0.160 (95%CI: 0.102, 0.230) that accounted for 26.10% of the total effect. Conclusion Job burnout among the college counselors is prominent. Job crafting presents an inhibitory effect on job burnout. Job stress indirectly affects the occurrence of job burnout by inhibiting the generation of job crafting.

OBJECTIVE: To explore the effects of nuclear protein-like transcription factor nuclear receptor subfamily 2 group E member 1 (NR2E1) on the growth, division, and proliferation of neuroblastoma cell line IMR32. METHODS: A NR2E1 shiRNA plasmid vector was constructed and transfected into neuroblastoma cell line IMR32 using lipofedamine™2000. Subsequent cell growth was measured by cell counting and the protein expression of somatic nuclear division was examined by immunofluorescent staining. RESULTS: At 48 h after the neuroblastoma cells IMR32 were transfected with NR2E1-shiRNA vector, the related nuclear division protein and the proliferation of the transfected cells IMR32 were remarkably depressed. CONCLUSION Cells division and proliferation of neuroblastoma cell line IMR32 is inhibited through transfection with the NR2E1-shiRNA plasmid vector.
Cell Division ; genetics ; physiology ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Neuroblastoma ; pathology ; RNA, Small Interfering ; genetics ; Receptors, Cytoplasmic and Nuclear ; genetics ; metabolism ; Transfection