1.Laboratory proficiency testing for creepage distance and electrical clearance test of medical electrical equipment based on GB 9706.1-2020
Xiao-Ming GAO ; Song-Yan XU ; Xiao-Peng HAN ; Zhen-Shi LIANG ; Man ZHANG ; Ting-Ru GUAN ; Hui-Ru WANG ; Yuan-Yuan QU ; Xin-Hua XIANG
Chinese Medical Equipment Journal 2024;45(10):54-59
Objective To clarify the understanding of types of laboratories and manufacturers for GB 9706.1-2020 Medical electrical equipment-Part 1:General requirements for basic safety and essential performance by laboratory proficiency testing for creepage distance and electrical clearance test.Methods An operation guide was formed according to the testing program in GB 9706.1-2020,and the homogeneity and stability of the samples were evaluated according to CNAS-GL003:2018 Guidance on Evaluating the Homogenneity and Stability of Samples Used for Proficiency Testing.Robust statistic methods were used to assess the quantitative parameters of the test results of the participating laboratories according to the requirements in GB/T 28043-2019 Statistical methods for use in proficiency testing by interlaboratory comparison;the results reported by the expert laboratories were used as the specified values of the qualitative parameters.SPSS 25.0 statistical software was used for data analysis.Results All the results of the crreepage distance and electrical clearance tests met the requirements for homogeneity and stability.Of the 46 laboratories involved in,37 ones did have comprehensive satisfactory determinations while the remained 9 ones not.Conclusion Some laboratories don't behave well in understanding the standard,which have to be reformed accordingly to enhance their proficiencies.[Chinese Medical Equipment Journal,2024,45(10):54-59]
2.A multicenter study of neonatal stroke in Shenzhen,China
Li-Xiu SHI ; Jin-Xing FENG ; Yan-Fang WEI ; Xin-Ru LU ; Yu-Xi ZHANG ; Lin-Ying YANG ; Sheng-Nan HE ; Pei-Juan CHEN ; Jing HAN ; Cheng CHEN ; Hui-Ying TU ; Zhang-Bin YU ; Jin-Jie HUANG ; Shu-Juan ZENG ; Wan-Ling CHEN ; Ying LIU ; Yan-Ping GUO ; Jiao-Yu MAO ; Xiao-Dong LI ; Qian-Shen ZHANG ; Zhi-Li XIE ; Mei-Ying HUANG ; Kun-Shan YAN ; Er-Ya YING ; Jun CHEN ; Yan-Rong WANG ; Ya-Ping LIU ; Bo SONG ; Hua-Yan LIU ; Xiao-Dong XIAO ; Hong TANG ; Yu-Na WANG ; Yin-Sha CAI ; Qi LONG ; Han-Qiang XU ; Hui-Zhan WANG ; Qian SUN ; Fang HAN ; Rui-Biao ZHANG ; Chuan-Zhong YANG ; Lei DOU ; Hui-Ju SHI ; Rui WANG ; Ping JIANG ; Shenzhen Neonatal Data Network
Chinese Journal of Contemporary Pediatrics 2024;26(5):450-455
Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75%(27/36);boys accounted for 64%(23/36).Among the 36 neonates,31(86%)had disease onset within 3 days after birth,and 19(53%)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61%)had left cerebral infarction and 13(36%)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75%)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72%)and seizures in 10 neonates(34%).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33%,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44%(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.
3.Exploring the key anti-fatigue components of American ginseng based on metabolomics and zebrafish models
Hui-ru LIU ; Hai-yang WANG ; Zhe WANG ; Li-guo CHEN ; Gui-dong CHENG ; Zhi-hui MA ; Song-song WANG ; Zheng-guo LI ; Li-wen HAN
Acta Pharmaceutica Sinica 2023;58(4):1024-1032
The aim of this paper is to explore the key anti-fatigue active components in the saponin-like composition of American ginseng. The anti-fatigue activity of western ginseng samples was evaluated using a zebrafish model; metabolomics techniques were used to identify the main saponins in western ginseng from different origins; the active substances and relevant targets of the anti-fatigue effect of western ginseng were initially screened by constructing a PPI protein interaction network between western ginseng saponins and disease targets, and the key active ingredients were screened using a molecular docking method; finally, the anti-fatigue activity of the key active ingredients was evaluated using a zebrafish, animal experiment was approved by the Ethics Committee of Shandong Academy of Medical Sciences (SYXK20220005). The anti-fatigue activity of the key active ingredients was evaluated using a zebrafish model. The results of the zebrafish activity evaluation showed that there were significant differences in the activities of the western ginseng samples from the two origins, and a total of 10 different saponins were identified as possibly related to the anti-fatigue activity after further metabolomic testing and pattern discrimination. The core anti-fatigue targets were screened with the help of component-disease target PPI, combined with pharmacophore-like parameters and molecular docking techniques, and pseudoginsenoside F11 was found to have good binding activity to five of the targets. Finally, the zebrafish model revealed that pseudoginsenoside F11 exhibited significant anti-fatigue activity. This study used metabolomics and zebrafish model to screen the key active substances of pseudoginsenoside F11 for its anti-fatigue activity, which will provide a reference for further research on the anti-fatigue of pseudoginsenosides.
4.Electroacupuncture at acupoints of yangming meridians for sarcopenia: a randomized controlled trial.
Su-Fan MA ; Wan-Yong LV ; Qian-Yang ZHU ; Hui-Jia LI ; Jing-Jing LI ; Qian SHI ; Xin-Ru LU ; Han-Yue YAO ; Cai-Rong ZHANG
Chinese Acupuncture & Moxibustion 2023;43(10):1114-1117
OBJECTIVE:
To observe the clinical effect of electroacupuncture at acupoints of yangming meridians for sarcopenia.
METHODS:
A total of 60 patients with sarcopenia were randomized into an observation group and a control group, 30 cases in each group. In the control group, conventional nutrition intervention for sarcopenia was adopted. In the observation group, on the basis of the treatment in the control group, acupuncture was applied at bilateral Binao (LI 14), Quchi (LI 11), Zusanli (ST 36), Yanglingquan (GB 34), etc.,ipsilateral Quchi (LI 11) and Zusanli (ST 36) were connected to electroacupuncture, with discontinuous wave, 2 Hz in frequency, 1-10 mA in intensity, 2 times a week, with a interval of 3 days. A total of 12-week treatment was required in the two groups. Before and after treatment, the appendicular skeletal muscle mass index (ASMI), grip strength, 6 m-walking time, body fat percentage and body moisture percentage were observed in the two groups.
RESULTS:
Compared with those before treatment, after treatment, ASMI and grip strength were increased while 6 m-walking time was shortened in the two groups (P<0.05); body fat percentage was decreased while body moisture percentage was increased in the observation group (P<0.05). After treatment, in the observation group, ASMI, grip strength and body moisture percentage were increased (P<0.05), 6 m-walking time was shortened and body fat percentage was decreased (P<0.05) compared with those in the control group.
CONCLUSION
Electroacupuncture at acupoints of yangming meridians can effectively improve the skeletal muscle mass, muscle function, body fat percentage and body moisture percentage in patients with sarcopenia, and make the distribution of muscle and fat more reasonable.
Humans
;
Meridians
;
Acupuncture Points
;
Electroacupuncture
;
Sarcopenia/therapy*
;
Acupuncture Therapy
5.Analysis of management efficacy in patients with heavy menstrual bleeding associated with antithrombotic therapy.
Xiao Lin JIANG ; Xin YAN ; Hui Na SU ; Yan Hua LIU ; Ru Xue HAN ; Zi Yi SONG ; Xiao Wan SUN ; De Hui SU ; Xin YANG
Chinese Journal of Obstetrics and Gynecology 2023;58(4):286-292
Objective: To evaluate different methods' efficacy of controlling acute bleeding and managing long-term menstruation in patients with heavy menstrual bleeding (HMB) associated with antithrombotic therapy. Methods: The clinical data of 22 cases with HMB associated with antithrombotic therapy admitted to Peking University People's Hospital from January 2010 to August 2022 were analyzed, aged 39 years old (26-46 years). Changes in menstrual volume, hemoglobin (Hb), and quality of life were collected after control of acute bleeding and long-term menstrual management. Menstrual volume was assessed by pictorial blood assessment chart (PBAC), and quality of life was assessed by menorrhagia multi-attribute scale (MMAS). Results: (1) Treatment of acute bleeding: of the 22 cases with HMB associated with antithrombotic therapy, 16 cases were treated in our hospital and 6 in other hospital for emergency bleeding; of the 16 cases treated in our hospital, 3 underwent emergency intrauterine Foley catheter balloon compression due to severe bleeding (Hb decreased by 20 to 40 g/L within 12 hours). Of the 22 cases with antithrombotic therapy-related HMB, 15 (including 2 cases with severe bleeding) underwent emergency aspiration or endometrial resection, and intraoperative placement of levonorgestrel-releasing intrauterine system (LNG-IUS) followed by a significant reduction in bleeding volume; 3 cases had controlled acute bleeding after rivaroxaban dose reduction and continued observation; 2 cases were given gonadotropin-releasing hormone agonists to control acute bleeding in other hospital, of which 1 case was temporarily treated with periodic blood transfusion, and the other one patient underwent total hysterectomy; and 2 cases had temporary amenorrhea with oral mifepristone after intrauterine balloon compression or oral norethindrone. (2) Long-term menstrual management: of the 22 cases with antithrombotic therapy-related HMB, 15 had LNG-IUS placement and 12 had LNG-IUS placement for 6 months, and menstrual volume was significantly reduced [PBAC scores were 365.0 (272.5-460.0) vs 25.0 (12.5-37.5), respectively; Z=4.593, P<0.001], Hb was significantly increased [91.5 g/L (71.8-108.2 g/L) vs 128.5 g/L (121.2-142.5 g/L); Z=4.695, P<0.001], and quality of life was significantly improved [MMAS scores were 415.0 (327.5-472.5) vs 580.0 (570.0-580.0), respectively; Z=-3.062, P=0.002] before placement compared with 6 months after placement. Three rivaroxaban dose reduction patients' PBAC scores decreased by 20 to 35 but remained >100, and perceived quality of life did not change significantly. Two cases with temporary amenorrhea treated with oral mifepristone felt significantly improved quality of life, and the MMAS scores increased by 220 and 180, respectively. Conclusion: Intrauterine Foley catheter balloon compression, aspiration or endometrial ablation could be used to control acute bleeding in patients with antithrombotic therapy-related HMB, and LNG-IUS for long-term management could reduce menstrual volume, increase hemoglobin, and improve the quality of life of patients.
Female
;
Humans
;
Adult
;
Menorrhagia/etiology*
;
Fibrinolytic Agents/adverse effects*
;
Levonorgestrel/adverse effects*
;
Amenorrhea/drug therapy*
;
Mifepristone/therapeutic use*
;
Quality of Life
;
Rivaroxaban/therapeutic use*
;
Hemoglobins
;
Intrauterine Devices, Medicated/adverse effects*
;
Contraceptive Agents, Female
6.Expression of Trichinella spiralis trehalase(TsTRE)protein and establishment of an indirect ELISA
Jia-Ming HOU ; Bo-Han ZHANG ; Ru-Lin RUAN ; Jian-Hui ZHANG ; Kun LIU ; Hao-Yuan CHEN ; Ming-Xin SONG ; Zi-Qun ZHANG
Chinese Journal of Zoonoses 2023;39(12):1174-1180
We established an indirect ELISA method using Trichinella spiralis trehalase(TsTRE)protein expressed in prokaryotic cells.The TsTRE gene was amplified by RT-PCR and ligated into the pCold I plasmid,which was expressed in E.coli BL21 competent cells.The rTsTRE protein was purified through affinity column chromatography.The TsTRE protein was localized with immunofluorescence techniques,and the immunogenicity of rTsTRE was detected by westernblotting.Subse-quently,rTsTRE protein was used as a coating antigen to establish an indirect ELISA.We optimized the antigen-coating con-centration,serum dilution concentration,antigen-coating incubation time,type of blocking solution,blocking incubation time,HRP-labeled goat anti-rabbit IgG serum dilution concentration,HRP-labeled goat anti-rabbit IgG serum incubation time and response time of TMB.Subsequently,the critical value,repeatability,sensitivity,specificity and clinical detection rate of the ELISA were evaluated.Immunofluorescence indicated that trehalase was abundant in the rod-shaped body,tail and epidermis of Trichinella spiralis muscle larvae.Western-blot indicated that rTsTRE protein combined with the positive serum of mice infected with T.spiralis for 42 d;the band was approximately 60 kDa.The established indirect ELISA had a positive threshold of 0.384;the intra-run and inter-run coefficients of variation were 5.504%-7.630% and 4.664%-9.929%,and did not exceed 10%.The lowest detectable titer was 1:1 280.No cross reaction was observed with antibodies to Clonorchissinensis,Schistosoma ja-ponicum,Ascaris suum,Toxocara gondii and Toxocara canis,and the clinical negative detection rate was 0%.Thus,we suc-cessfully expressed the rTsTRE protein.Moreover,the established indirect ELISA method using the TsTRE protein as the coating antigen had good repeatability,sensitivity,specificity and clinical detectability,and can be applied to the detection of clinical samples.
7.Efficacy and safety of neoadjuvant toripalimab combined with nimotuzumab and chemotherapy in patients with unresectable stage Ⅳ squamous cell carcinoma of penis.
Ru YAN ; Sheng Jie GUO ; Xin AN ; Li Juan JIANG ; Ting Yu LIU ; Ting XUE ; Hua Li MA ; Kai YAO ; Yan Xia SHI ; Hui HAN
Chinese Journal of Surgery 2022;60(12):1093-1099
Objective: To compare the efficacy and safety of neoadjuvant chemotherapy alone or combined with toripalimab and nimotuzumab in patients with unresectable locally advanced or metastatic squamous cell carcinoma of penis. Methods: A total of 33 patients with unresectable squamous cell carcinoma of penis undergoing neoadjuvant chemotherapy alone or combined with toripalimab and nimotuzumab at Sun Yat-sen University Cancer Center from May 2015 to June 2021 were enrolled retrospectively. All the patients were male, with a median age (M(IQR))of 49.0 (13.5) years (range: 30 to 70 years). According to the therapy protocols, patients were divided into the chemotherapy group (16 cases) and the triple combination group (17 cases). Log-rank test was used to compare the progression-free survival and overall survival. χ2 test or Fisher exact method was used to compare the objective response rate, pathological down-stage rate and adverse events between these two groups. Results: The follow-up time was 28.1(19.2) months (range: 1.5 to 33.4 months). Patients of triple combination group were observed significantly longer progression-free survival (30.0 months vs. 8.2 months, χ²=3.998, P=0.046) than those of chemotherapy group. The median overall survival of the triple combination group and chemotherapy group were not reached and 15.2 months (χ²=3.298, P=0.069), respectively. Although there was no significant difference in the subsequent surgical resection rate between these two groups (12/17 vs.11/16, P=1), the objective response rate and the pathological complete response rate in triple combination group were significantly higher than in chemotherapy group (13/17 vs. 6/16, χ²=5.125, P=0.024; 6/7 vs. 0, P=0.001). The main common grade 1 to 2 adverse events in the triple combination group were alopecia (16 cases), anemia (15 cases), and nausea (14 cases). The main common grade 1 to 2 adverse events in the chemotherapy group were anemia (14 cases), alopecia (12 cases), decreased appetite (12 cases), and nausea (11 cases). The incidence of adverse events ≥grade 3 was similar in the triple combination group and chemotherapy group (8/17 vs. 6/16, χ²=0.308, P=0.579). There was no grade 3 adverse event in both groups. Conclusion: Compared with traditional chemotherapy alone, chemotherapy combined with toripalimab and nimotuzumab provides longer progression-free survival and similar toxicity for unresectable stage Ⅳ squamous cell carcinoma of penis.
Humans
;
Male
;
Female
;
Neoadjuvant Therapy
;
Retrospective Studies
;
Carcinoma, Squamous Cell/drug therapy*
;
Alopecia
;
Anemia
8.Assessment of the Benefits of Targeted Interventions for Pandemic Control in China Based on Machine Learning Method and Web Service for COVID-19 Policy Simulation.
Jie Wen WU ; Xiao Kang JIAO ; Xin Hui DU ; Zeng Tao JIAO ; Zuo Ru LIANG ; Ming Fan PANG ; Han Ran JI ; Zhi Da CHENG ; Kang Ning CAI ; Xiao Peng QI
Biomedical and Environmental Sciences 2022;35(5):412-418
Taking the Chinese city of Xiamen as an example, simulation and quantitative analysis were performed on the transmissions of the Coronavirus Disease 2019 (COVID-19) and the influence of intervention combinations to assist policymakers in the preparation of targeted response measures. A machine learning model was built to estimate the effectiveness of interventions and simulate transmission in different scenarios. The comparison was conducted between simulated and real cases in Xiamen. A web interface with adjustable parameters, including choice of intervention measures, intervention weights, vaccination, and viral variants, was designed for users to run the simulation. The total case number was set as the outcome. The cumulative number was 4,614,641 without restrictions and 78 under the strictest intervention set. Simulation with the parameters closest to the real situation of the Xiamen outbreak was performed to verify the accuracy and reliability of the model. The simulation model generated a duration of 52 days before the daily cases dropped to zero and the final cumulative case number of 200, which were 25 more days and 36 fewer cases than the real situation, respectively. Targeted interventions could benefit the prevention and control of COVID-19 outbreak while safeguarding public health and mitigating impacts on people's livelihood.
COVID-19/prevention & control*
;
China/epidemiology*
;
Humans
;
Machine Learning
;
Pandemics/prevention & control*
;
Policy
;
Reproducibility of Results
;
SARS-CoV-2
9.Inhibition of TAK1 aggravates airway inflammation by increasing RIPK1 activity and promoting macrophage death in a mouse model of toluene diisocyanate-induced asthma.
Shu Luan YANG ; Wen Qu ZHAO ; Xian Ru PENG ; Zi Han LAN ; Jun Wen HUANG ; Hui Shan HAN ; Ying CHEN ; Shao Xi CAI ; Hai Jin ZHAO
Journal of Southern Medical University 2022;42(2):181-189
OBJECTIVE:
To explore the effect of transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) on toluene diisocyanate (TDI)-induced allergic airway inflammation in mice.
METHODS:
Thirty-two mice were randomly divided into AOO group, AOO+5Z-7-Oxozeaenol group, TDI group, and TDI+5Z-7-Oxozeaenol group. Another 32 mice were randomly divided into AOO group, TDI group, TDI +5Z-7-Oxozeaenol group, and TDI +5Z-7-Oxozeaenol + Necrostatin-1 group. TAK1 inhibitor (5Z-7-Oxozeaenol, 5 mg/kg) and/or RIPK1 inhibitor (Necrostatin-1, 5 mg/kg) were used before each challenge. Airway responsiveness, airway inflammation and airway remodeling were assessed after the treatments. We also examined the effect of TDI-human serum albumin (TDI-HSA) conjugate combined with TAK1 inhibitor on the viability of mouse mononuclear macrophages (RAW264.7) using CCK8 assay. The expressions of TAK1, mitogen-activated protein kinase (MAPK) and receptor interacting serine/threonine protease 1 (RIPK1) signal pathway in the treated cells were detected with Western blotting. The effects of RIPK1 inhibitor on the viability of RAW264.7 cells and airway inflammation of the mouse models of TDI-induced asthma were evaluated.
RESULTS:
TAK1 inhibitor aggravated TDI-induced airway inflammation, airway hyper responsiveness and airway remodeling in the mouse models (P < 0.05). Treatment with TAK1 inhibitor significantly decreased the viability of RAW264.7 cells, which was further decreased by co-treatment with TDI-HSA (P < 0.05). TAK1 inhibitor significantly decreased the level of TAK1 phosphorylation and activation of MAPK signal pathway induced by TDI-HSA (P < 0.05). Co-treatment with TAK1 inhibitor and TDI-HSA obviously increased the level of RIPK1 phosphorylation and caused persistent activation of caspase 8 (P < 0.05). RIPK1 inhibitor significantly inhibited the reduction of cell viability caused by TAK1 inhibitor and TDI-HSA (P < 0.05) and alleviated the aggravation of airway inflammation induced by TAK1 inhibitors in TDI-induced mouse models (P < 0.05).
CONCLUSION
Inhibition of TAK1 aggravates TDI-induced airway inflammation and hyperresponsiveness and may increase the death of macrophages by enhancing the activity of RIPK1 and causing persistent activation of caspase 8.
Animals
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Asthma/chemically induced*
;
Inflammation
;
Macrophages
;
Mice
;
Receptor-Interacting Protein Serine-Threonine Kinases
;
Respiratory System
;
Toluene 2,4-Diisocyanate/adverse effects*
10.Carbenoxolone enhances inhibitory effect of RSL3 against cisplatin-resistant testicular cancer cells by promoting ferroptosis.
Jia Ru DU ; Bin LI ; Chen Lu ZHU ; Jia Le HAN ; Xu Hui TONG
Journal of Southern Medical University 2022;42(3):405-410
OBJECTIVE:
To investigate the inhibitory effect of RSL3 on the proliferation, invasion and migration of cisplatinresistant testicular cancer cells (I-10/DDP) and the effect of carbenoxolone on the activity of RSL3 against testicular cancer.
METHODS:
MTT assay was used to evaluate the survival rate of I-10/DDP cells following treatment with RSL3 (1, 2, 4, 8, 16 or 32 μmol/L) alone or in combination with carbenoxolone (100 μmol/L) or after treatment with Fer-1 (2 μmol/L), RSL3 (4 μmol/L), RSL3+Fer-1, RSL3+carbenoxolone (100 μmol/L), or RSL3+Fer-1+carbenoxolone. Colony formation assay was used to assess the proliferation ability of the treated cells; wounding-healing assay and Transwell assay were used to assess the invasion and migration ability of the cells. The expression of GPX4 was detected using Western blotting, the levels of lipid ROS were detected using C11 BODIPY 581/591 fluorescent probe, and the levels of Fe2+ were determined with FerroOrange fluorescent probe.
RESULTS:
RSL3 dose-dependently decreased the survival rate of I-10/DDP cells, and the combined treatment with 2, 4, or 8 μmol/L RSL3 with carbenoxolone, as compared with RSL3 treatment alone, resulted in significant reduction of the cell survival rate. The combination with carbenoxolone significantly enhanced the inhibitory effect of RSL3 on colony formation, wound healing rate (P=0.005), invasion and migration of the cells (P < 0.001). Fer-1 obviously attenuated the inhibitory effects of RSL3 alone and its combination with carbenoxolone on I-10/DDP cells (P < 0.01). RSL3 treatment significantly decreased GPX4 expression (P=0.001) and increased lipid ROS level (P=0.001) and Fe2+ level in the cells, and these effects were further enhanced by the combined treatment with carbenoxolone (P < 0.01).
CONCLUSION
Carbenoxolone enhances the inhibitory effect of RSL3 on the proliferation, invasion and migration of cisplatin-resistant testicular cancer cells by promoting RSL3-induced ferroptosis.
Carbenoxolone/pharmacology*
;
Cell Line, Tumor
;
Cell Proliferation
;
Cisplatin/pharmacology*
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Ferroptosis
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Fluorescent Dyes/pharmacology*
;
Humans
;
Lipids
;
Male
;
Neoplasms, Germ Cell and Embryonal
;
Reactive Oxygen Species
;
Testicular Neoplasms

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