Objective To observe the effect of different concentrations of glutamine(Gln)on the radiosensitivity of colorectal cancer HT-29 cells and explore the possible mechanism.Methods According to different Gln concentrations,HT-29 cells at logarithmical growth were divided into control group(2 mmol/L,as the basal medium concentration group)and experimental groups Ⅰ,Ⅱ and Ⅲ(4,6 and 8 mmol/L).After a 2-hour pre-treatment,all groups were exposed to 8 Gy irradiation of a Co-60 radiation source.CCK-8 assay and clonal formation assay were used respectively to explore the effects of different Gln concentrations on cell viability and cell radiosensitivity after irradiation.The level of reactive oxygen species(ROS)in each group was measured in 24 h after irradiation,and the apoptotic rate was detected with flow cytometry in 48 h after irradiation.The protein expression levels of Nrf2,HO-1,and cleaved-Caspase3 were determined by Western blotting.Results In 24 h after Gln intervention,the cell viability of experimental groups Ⅱ and Ⅲof non-irradiated HT-29 cells was significantly higher than that of the control group and of experimental group Ⅰ(P＜0.05).In 24 h after radiation,the cell viability of each experimental group was significantly higher than that of the control group(P＜0.05).In 14 d after radiation,there were more clone formation in each experimental group than the control group(P＜0.05).The ROS level was significantly lower in each experimental group than the control group in 24 h after radiation(P＜0.05).After 48 h of radiation,the apoptotic rate was notably lower in each experimental group than the control group(P＜0.05).The expression level of Nrf2 in the experimental group Ⅰ was higher than that of the control group(P＜0.05),those of Nrf2 and HO-1 in the experimental groups Ⅱ and Ⅲ were higher than those of the control group and experimental group Ⅰ(P＜0.05).While the expression of cleaved-Caspase3 in the experimental groups Ⅱ and Ⅲ was lower than the control group and experimental group Ⅰ(P＜0.05),and it in the experimental group Ⅲ was lower than that of experimental group Ⅱ(P＜0.05).Conclusion Gln can significantly reduce the radiosensitivity of HT-29 cells,which is associated with its reducing oxidative stress damage and reducing cell apoptosis.Our results suggest that Gln might be detrimental to radiation therapy in patients with colorectal cancer.

Oxygen therapy is an effective clinical method for the treatment of respiratory disorders, oxygen concentrator as a necessary medical auxiliary equipment in hospitals, its research and development has been a hot spot. The study reviewed the development history of the ventilator, introduced the two preparation technique of the oxygen generator pressure swing absorption (PSA) and vacuum pressure swing adsorption (VPSA), and analyzed the core technology development of the oxygen generator. In addition, the study compared some major brands of oxygen concentrators on the market and prospected the development trend of oxygen concentrators.
Oxygen ; Oxygen Inhalation Therapy ; Hospitals ; Ventilators, Mechanical ; Equipment Design

Ventilator is an indispensable emergency medical equipment in hospitals. The global outbreak of the coronavirus disease 2019 (COVID-19) has highlighted the importance of the ventilator, which has attracted the attention and research on ventilators of all countries in the world. This article reviews the development history of the ventilator, briefly introduces the main air circuit structure and working principle of the ventilator, and then deeply analyzes the key technologies of this device. In addition, it compares some major brands of ventilators from several aspects in the market. Finally, the development trend and perspective of ventilators are presented.
COVID-19 ; Equipment Design ; Home Care Services ; Humans ; Respiration, Artificial ; SARS-CoV-2 ; Ventilators, Mechanical

Objective:To evaluate the cancer detection rate in patients with multiparametric magnetic resonance imaging (mpMRI) PI-RADS 1-2 prior to initial biopsy, and analyze the risk factors of prostate cancer.Methods:A total of 196 patients undergoing initial prostate biopsy between July 2011 and June 2018 were retrospectively analyzed. According to ESUR PI-RADS system, the patients’ PI-RADS score was 1 and 2, with the mean age of 66.6±9.0 years, and the median PSA 7.44 ng/ml. Twenty-eight patients were enrolled with PSA<4 ng/ml but with abnormal directeral rectun examination. The rest 168 patients were enrolled with elevated PSA. According to the Epstein prostate risk classification criteria, clinically insignificant prostate cancer was defined as: PSA density ≤0.15 ng/ml 2, Gleason score≤6, less than 3 positive needles, <50% puncture length. If any of the above is not met, the diagnosis should be clinically significant prostate cancer(CsPCa). T test or Mann-Whitney U test were used for comparison between groups. Risk factors for diagnosis of prostate cancer and CsPCa were analyzed by chi square test(or Fisher’s exact probability method) and multivariate logistic regression analysis. Results:There were 42(21.4%) patients diagnosed with prostate cancer, 30(15.3%)patients were CsPCa. The negative predictive value of mpMRI was 78.6%(154/196)for prostate cancer overall, and 84.7%(166/196)for CsPCa. Patients with higher age and PSA density were associated with higher possibility of prostate cancer. Higher age, PSA level, PSA density, and lower PSA ratio were associated with higher possibility of CsPCa. Multivariate logistic regression analysis showed that PSA density>0.15 ng/ml 2( OR=2.94, 95% CI 1.45-5.95) was independent risk factor of prostate cancer.Ages over 70 years( OR=2.49, 95% CI 1.22-5.07), PSA ratio<0.2( OR=3.70, 95% CI 1.25-11.23), PSA density>0.15 ng/ml 2( OR=5.77, 95% CI 1.96-16.96) were independent risk factors of CsPCa ( P<0.05). Conclusions:The detection rate of prostate cancer was 21.4% in patients with elevated PSA or abnormal digital prostate examination but with PI-RADS score of 1-2. Higher age and PSA density were associated with higher risk of prostate cancer. The detection rate of CsPCa was 15.3%. Ages over 70 years, PSA ratio<0.2, PSA density>0.15 ng/ml 2 were independent risk factors of CsPCa.

Objective:To analyze the prognosis of patients with positive resection margin after radical prostatectomy, as well as the prostate-specific antigen (PSA)level and risk factors for PSA progression.Methods:A retrospective analysis was performed on the data of 141 patients with pathologically diagnosed prostate cancer who underwent RP from May 2012 to August 2020 in Beijing Hospital. The mean age was (67.4±6.7)years, the preoperative median PSA was 9.6 (1.4-152.8) ng/ ml and the median follow-up time was 56 months. Postoperative pathology was T 2 stage 74 (52.5%), T 3 stage 63 (44.7%), T 4 stage 4 (2.8%). Biochemical recurrence after radical resection was defined as PSA rose to more than 0.2 ng/ml and showed an upward trend after two consecutive follow-ups. In this study, serum PSA ≥ 0.1 ng/ml without biochemical recurrence after radical operation was defined as PSA progression. The PSA level, risk factors of PSA progression and prognosis of patients with positive resection margin were analyzed. Univariate and multivariate Cox regression analysis was used to analyze the correlation between age, preoperative PSA level, pathological stage (pT), ISUP classification, surgical approach, lymph node dissection, single/multiple positive margins and PSA progression. Results:The median follow-up of 141 patients was 52 months(1-104 months). There were 69 (48.9%) patients in the PSA progression group and 72 (51.1%) patients in the non PSA progression group. In the PSA progression group, 13 (18.8%) patients did not receive treatment and 8 (61.5%) patients had biochemical recurrence. 4 (5.8%) patients received radiotherapy alone, and 2 (50.0%) patients had biochemical recurrence. 52 (75.4%) patients received endocrine therapy or endocrine therapy combined with radiotherapy, and 5 (9.6%) patients developed castration resistance. Multivariate Cox regression analysis showed preoperative PSA ( HR=1.015, 95% CI 1.005-1.025, P =0.004), ISUP grade and group ( HR=1.351, 95% CI 1.091-1.673, P =0.006), surgical method ( HR=2.233, 95% CI 1.141-4.370, P =0.019) was correlated with PSA progression. Conclusions:The incidence of surgical positive margin is high after RP. Nearly half of the patients with surgical positive margin developed a PSA progression status. Preoperative PSA, ISUP grade group, and the surgical approach are risk factors for PSA progression in patients with positive surgical margins. Patients with these risk factors should be monitored more closely and treated more aggressively.

Objective:To analyze the clinical features and prognosis of pediatric non-rhabdomyosarcoma soft tissue sarcoma (NRSTS), and further understand these tumors.Methods:Twenty-nine NRSTS children were admitted to the Hematological Oncology Ward of Beijing Children′s Hospital from June 2011 to May 2018.The clinical and pathological data of these children were collected, and the relationships of the prognosis with clinical characteristics Intergroup Rhabdomyosarcoma Study(IRS) stage, Children′s Oncology Group(COG) risk grouping were analyzed.All the patients were followed up until October 31, 2018.The survival analysis was performed by Kaplan-Meier method.Results:There were 14 boys and 15 girls in the enrolled 29 children, aging from 7 to 169 months, with a median age of 59.5 months.There were 10 pathological types, including synovial sarcoma, infantile fibrosarcoma and malignant rhabdomyoid tumors in 5 cases, and other pathological types in 14 cases.Tumors originated from the head and neck in 10 cases, limbs or trunk in 6 cases, visceral sites in 13 cases.Ten cases showed distant metastasis.There were 12 cases at IRS stage Ⅰand Ⅱ, and 17 cases of stage Ⅲ and Ⅳ.All the children were treated with surgery and chemotherapy with or without radiotherapy.Nine cases received preoperative chemotherapy, 17 cases received postoperative chemotherapy, 3 cases could not be resected surgically.The follow-up period ranged from 4 to 89 months, with a median follow-up of 16 months.Six of 29 children died, including 3 cases of malignant rhabdomyoid sarcoma.The 2-year overall survival(OS) rate of all the children was 77.4% and the 2-year event-free survival (EFS) rate of all the children was 53.2%.By analyzing the clinical factors, it was found that the IRS stage, COG risk group, primary sites were related to prognosis.The 2-year EFS rate of children with IRS Ⅰ-Ⅱ and Ⅲ-Ⅳ were 75.0% and 35.9%, respectively ( χ2=7.303, P=0.007), the 2-year OS rate was 100% and 61.8%, respectively( χ2=4.81, P=0.028); The 2-year EFS of children in COG low-risk group and median/high-risk group were 66.7% and 44.7%, respectively( χ2=4.155, P=0.042), the 2-year OS rate of children in COG low and median/high-risk was 100% and 66.3%, respectively( χ2=3.383, P=0.066); the 2-year OS rate of children in visceral and non-visceral sites were 59.3% and 92.9%, respectively ( χ2=4.202, P=0.04). Conclusions:NRSTS in children is heterogeneous, and surgery is the main treatment. Children with primary tumors located in visceral sites and at IRS Ⅲ-Ⅳ had poor outcomes.

Objective To investigate the effects of radical prostatectomy on the overall survival (OS)and tumor-specific survival in prostate cancer(PCa)patients aged 75 years and older.Methods Clinical data of patients aged 75 and older with localized PCa from Surveillance,Epidemiology,and End Results(SEER)Database from 2004 to 2016 were retrospectively analyzed.There were 17 899 cases of PCa undergoing radical prostatectomy and 3 648 cases of PCa without surgery in this study.The OS and prostate cancer-specific survival(PSS)were compared between the surgery group and the nonsurgery group.Results For 75-79-year-old patients with high-risk localized PCa,the OS and PSS in the surgery group were better than in the non-surgery group (OR =1.49,95 ％ CI:1.22 ～ 1.82,P ＜ 0.01;OR=1.43,95％CI:1.09～2.04,P＜0.05).For patients aged 75-79 years with low-risk PCa and patients aged 80 years and older with low-,middle-,or high-risk PCa,the OS was worse in the surgery group than in the non-surgery group(OR =0.54,95％CI:0.38～0.76,P＜0.01;OR =0.47,95％CI:0.34～0.66,P＜0.01;OR =0.58,95％CI:0.44～0.78,P＜0.01;OR =0.59,95％CI:0.51 ～0.68,P＜0.01).For patients aged 75-79 years with low-or medium-risk PCa and patients aged 80 years and older with medium-risk PCa,there was no statistical difference in PSS between the surgery and non-surgery groups(P＞0.05).Conclusions Age limits for prostatectomy should be extended as a result of increasing average life expectancy.Patients aged 75-79 years with high-risk PCa can be considered for surgical treatment,while it should not be recommended for patients aged 75-79 years with low-or medium-risk localized PCa or aged more than 80 years.Many factors should be considered in making treatment decisions for prostate cancer.

Objective To verify the safety and advantages of total transperitoneal laparoscopic nephroureterectomy (ttLNU) in the treatment of upper urinary tract urothelial carcinoma (UTUC).Methods From Jun.2013 to Jun.2014,there were 13 UTUC patients treated with ttLNU,including 7 males and 6 females.The mean age was 70.4 ± 8.3 yrs,and BMI was 23.3±4.1.Of them,11 cases were diagnosed with renal pelvis carcinoma,6 in the left and 5 in the right.2 cases were diagnosed with left ureteral carcinoma.TNM stages were T1-T3N0M0.Patients were put on lateral position and the position was not changed during the operation.A ttLNU was performed,and the specimen was removed from the middle extended inferior umbilical incision.Results The mean operative time was 188±33 (150-240) min,the intraoperative blood loss was 150.5±60.1 (50-700) ml,and the time of out-of-bed activity was between 1 and 4 d.The mean postoperative drainage time was 6.8±4.6 (3-6) d.The mean postoperative bowel function recovery time was 1.5± 1.0 (2-4) d and postoperative hospital stay was 12.8±7.0 (3-27) d.The ttLNU procedures were successfully performed in all cases without conversion to open surgery.Pathological results showed urothelial carcinoma in all cases,including 8 high grade and 5 low grade.All the surgical margins were negative.The followed up was from 2 to 12 mon,and there was no tumor recurrence and metastasis found.Conclusions Total transperitoneal laparoscopic nephroureterectomy in the treatment of upper urinary tract urothelial carcinoma is characterized by short operative time,low blood loss,decreased trauma and quick recovery.This is a safe and effective treatment option for the treatment of upper urinary tract urothelial carcinoma.

Objective To use enzyme-linked immunosorbent assay (ELISA) for measuring thrombospondin-1 (TSP-1),and to analyze its diagnostic value for prostatic carcinoma.Methods The possible difficulties and the way to solve the difficulties with ELISA spot were explored first.Three agents which could segregate idio-antigen and one technique which could depurate proteinum were designed and developed.The non- idio- proteinum cross reaction problems were solved and the routine method to measure TSP-1 with ELISA was set up successfully.The serum TSP-1 was measured in 14 patients with benign prostatic hyperplasia (BPH) and 18 patients with prostatic carcinoma.Results The TSP-1 values were (73.77±12.72)% and (121.86±-19.47)% in prostatic carcinoma group and benign prostatic hyperplasia group,respectively (t= 8.44,P＜0.01).The diagnostic sensitivity and specificity of TSP-1 and prostate specific antigen (PSA) for prostatic cancer were 92.7%,88.9% and 85.7%,66.7%,respectively (P＜0.01).The area under the receiver operating characteristic curve (ROC) of TSP-1 and PSA were 0.9663 and 0.7421 (P＜0.05).Conclusions The determination of TSP-1 with ELISA is feasible.TSP-1 is an ideal diagnostic parameter for prostatic carcinoma and it may distinguish BPH from malignant prostatic disease more exactly than PSA.

Objective To evaluate the morbidity trend of prostate cancer since the clinical usage of PSA was introduced in Beijing Hospital.Methods Retrospectively we analyzed prostate cancer cases diagnosed in Beijing Hospital from 1995 to 2008.The incidence, age, PSA and clinical stage at diagnosis were taken into account.Results Four hundred and thirty-two cases were enrolled into the study.Who were aged 40 - 90 years old, mean age 72.0 ± 7.8 years.The most frequent age at diagnosis was 70 to 79 years.The incidence increased annually with the most significant increase taking place in 2007 and 2008.Compared with the period 1995 to 1999, the localized prostate cancer rate between 2004 and 2008 increased from 23.9% to 36.3%; the metastatic prostate cancer rate decreased from 49.3% to 32.1%; the rate of patients with PSA 4 - 10 ng,/ml increased from 12.7% to 29.2%; the rate of PSA ＞ 100 ng/ml decreased from 22.5% to 13.2%.Conclusions The incidence and early detection rate of prostate cancer in Beijing Hospital increased from 1995 to 2008.The age at diagnosis had not significantly changed.However, the early detection rate should be improved.