1.Application and clinical efficacy of red blood cell therapeutic apheresis in erythropoietic protoporphyria and hereditary hemochromatosis
Haoqiang LIU ; Caihan ZHAO ; Qing YUAN ; Lixia XIE ; Yong ZOU ; Ying LU
Chinese Journal of Blood Transfusion 2025;38(7):915-921
Objective: To explore the application and clinical efficacy of red blood cell therapeutic apheresis in erythropoietic protoporphyria (EPP) and hereditary hemochromatosis (HH). Methods: 1) The EPP patient was hospitalized twice for "abdominal pain, nausea, vomiting, and brown urine". One and two sessions of red blood cell exchange/therapeutic plasma exchange (RCE/TPE) were respectively performed during the two hospitalizations. During each session, one RCE with 6-8 units of leukoreduced RBCs and 3-4 TPE procedures with 1 800-2 000 mL of frozen plasma was conducted. Biochemical parameters were monitored before and after treatment. 2) The HH patient was hospitalized for “repeatedly elevated aminotransferases”. Erythrocytapheresis was performed once, removing 550 mL of red blood cells, and venous phlebotomy was conducted once every 2 months subsequently. Blood routine and ferritin levels were assessed before and after treatment. Results: 1) During the first hospitalization, the EPP patient was relieved of the abdominal pain and brown urine after therapeutic apheresis. The total bilirubin level decreased from 141.8 μmol/L on admission to 68.6 μmol/L at discharge, with a symptom remission duration of 10 months. During the second hospitalization, the EPP patient still had recurrent abdominal pain after therapeutic apheresis. He developed psychiatric symptoms and gastrointestinal bleeding subsequently, accompanied by elevated bilirubin levels. Liver function deteriorated and the patient went into the state of the end-stage liver disease (ESLD). 2) For the HH patient, the hemoglobin level prior to erythrocytapheresis and vein phlebotomy was 150-160 g/L, with the lowest value occurring two days after erythrocytapheresis, decreasing to 107 g/L. The ferritin level before erythrocytapheresis was 2 428.08 ng/mL and it declined gradually after theraphy, with the lowest value occurring two months after erythrocytapheresis, decreasing to 1 094 ng/mL. The ferritin level was 1 114 ng/mL two months following the first vein phlebotomy, however it increased to 1 472 ng/mL two months after the second vein phlebotomy. Conclusion: RCE/TPE may alleviate protoporphyrin liver disease and help patients with bridging liver transplantation before EPP developments to ESLD. For HH patients with significantly elevated ferritin levels, erythrocytapheresis reduces serum ferritin more quickly and maintains its level longer relative to phlebotomy.
2.Application and clinical efficacy of red blood cell therapeutic apheresis in erythropoietic protoporphyria and hereditary hemochromatosis
Haoqiang LIU ; Caihan ZHAO ; Qing YUAN ; Lixia XIE ; Yong ZOU ; Ying LU
Chinese Journal of Blood Transfusion 2025;38(7):915-921
Objective: To explore the application and clinical efficacy of red blood cell therapeutic apheresis in erythropoietic protoporphyria (EPP) and hereditary hemochromatosis (HH). Methods: 1) The EPP patient was hospitalized twice for "abdominal pain, nausea, vomiting, and brown urine". One and two sessions of red blood cell exchange/therapeutic plasma exchange (RCE/TPE) were respectively performed during the two hospitalizations. During each session, one RCE with 6-8 units of leukoreduced RBCs and 3-4 TPE procedures with 1 800-2 000 mL of frozen plasma was conducted. Biochemical parameters were monitored before and after treatment. 2) The HH patient was hospitalized for “repeatedly elevated aminotransferases”. Erythrocytapheresis was performed once, removing 550 mL of red blood cells, and venous phlebotomy was conducted once every 2 months subsequently. Blood routine and ferritin levels were assessed before and after treatment. Results: 1) During the first hospitalization, the EPP patient was relieved of the abdominal pain and brown urine after therapeutic apheresis. The total bilirubin level decreased from 141.8 μmol/L on admission to 68.6 μmol/L at discharge, with a symptom remission duration of 10 months. During the second hospitalization, the EPP patient still had recurrent abdominal pain after therapeutic apheresis. He developed psychiatric symptoms and gastrointestinal bleeding subsequently, accompanied by elevated bilirubin levels. Liver function deteriorated and the patient went into the state of the end-stage liver disease (ESLD). 2) For the HH patient, the hemoglobin level prior to erythrocytapheresis and vein phlebotomy was 150-160 g/L, with the lowest value occurring two days after erythrocytapheresis, decreasing to 107 g/L. The ferritin level before erythrocytapheresis was 2 428.08 ng/mL and it declined gradually after theraphy, with the lowest value occurring two months after erythrocytapheresis, decreasing to 1 094 ng/mL. The ferritin level was 1 114 ng/mL two months following the first vein phlebotomy, however it increased to 1 472 ng/mL two months after the second vein phlebotomy. Conclusion: RCE/TPE may alleviate protoporphyrin liver disease and help patients with bridging liver transplantation before EPP developments to ESLD. For HH patients with significantly elevated ferritin levels, erythrocytapheresis reduces serum ferritin more quickly and maintains its level longer relative to phlebotomy.
3.Effect and mechanism of protein kinase N1 on the proliferation of mouse cardiomyocytes
Zonglei ZHAO ; Songge CHEN ; Suofeng SUN ; Lixia WANG
Journal of Xinxiang Medical College 2024;41(3):204-208
Objective To explore the effect and mechanism of protein kinase N1(PKN1)on the proliferation of mouse cardiomyocytes.Methods Two 1-day-old mice were anesthetized with isoflurane,and their cardiomyocytes were isolated and divided into the control group and the interference group.The cardiomyocytes in the interference group were transfected with PKN1 fragments,while the cardiomyocytes in the control group were transfected with control fragments.According to the random number table method,10 mice were divided into the normal group and the observation group,with 5 mice in each group.The mice in the observation group were injected with PKN1 adenovirus in situ in the heart,while the mice in the normal group were injected with empty adenovirus in situ in the heart.The Ki-67 positive expression in myocardial cells and tissues of mice in the four groups was detected by immunofluorescence assay,indicating the proliferation ability of cardiomyocytes.The PKN1 mRNA expression in cardiomyocytes of mice in the control group and interference group was measured by real-time fluorescence quan-titative polymerase chain reaction.The expression of PKN1 and cyclin D1 proteins in cardiomyocytes of mice in the control group and interference group was determined by Western blot.Results The positive expression rates of Ki-67 in myocardial cells of mice in the interference group was significantly lower than that in the control group(t=11.201,P<0.01);the positive expression rate of Ki-67 in myocardial tissue of mice in the observation group was significantly lower than that in the normal group(t=11.851,P<0.01).The relative expression level of PKN1 mRNA in cardiomyocytes of mice in the interference group was significantly lower than that in the control group(t=7.022,P<0.01).The relative expression levels of PKN1 and cyclin D1 proteins in cardiomyocytes of mice in the interference group were significantly lower than those in the control group(t=5.762,6.884;P<0.01).Conclusion The decreased expression of PKN1 in mouse cardiomyocytes can inhibit the expression of cyclin D1 protein,thereby restraining cardiomyocyte proliferation.
4.Development of the robotic digestive endoscope system and an experimental study on mechanistic model and living animals (with video)
Bingrong LIU ; Yili FU ; Kaipeng LIU ; Deliang LI ; Bo PAN ; Dan LIU ; Hao QIU ; Xiaocan JIA ; Jianping CHEN ; Jiyu ZHANG ; Mei WANG ; Fengdong LI ; Xiaopeng ZHANG ; Zongling KAN ; Jinghao LI ; Yuan GAO ; Min SU ; Quanqin XIE ; Jun YANG ; Yu LIU ; Lixia ZHAO
Chinese Journal of Digestive Endoscopy 2024;41(1):35-42
Objective:To develop a robotic digestive endoscope system (RDES) and to evaluate its feasibility, safety and control performance by experiments.Methods:The RDES was designed based on the master-slave control system, which consisted of 3 parts: the integrated endoscope, including a knob and button robotic control system integrated with a gastroscope; the robotic mechanical arm system, including the base and arm, as well as the endoscopic advance-retreat control device (force-feedback function was designed) and the endoscopic axial rotation control device; the control console, including a master manipulator and an image monitor. The operator sit far away from the endoscope and controlled the master manipulator to bend the end of the endoscope and to control advance, retract and rotation of the endoscope. The air supply, water supply, suction, figure fixing and motion scaling switching was realized by pressing buttons on the master manipulator. In the endoscopy experiments performed on live pigs, 5 physicians each were in the beginner and advanced groups. Each operator operated RDES and traditional endoscope (2 weeks interval) to perform porcine gastroscopy 6 times, comparing the examination time. In the experiment of endoscopic circle drawing on the inner wall of the simulated stomach model, each operator in the two groups operated RDES 1∶1 motion scaling, 5∶1 motion scaling and ordinary endoscope to complete endoscopic circle drawing 6 times, comparing the completion time, accuracy (i.e. trajectory deviation) and workload.Results:RDES was operated normally with good force feedback function. All porcine in vivo gastroscopies were successful, without mucosal injury, bleeding or perforation. In beginner and advanced groups, the examination time of both RDES and ordinary endoscopy tended to decrease as the number of operations increased, but the decrease in time was greater for operating RDES than for operating ordinary endoscope (beginner group P=0.033; advanced group P=0.023). In the beginner group, the operators operating RDES with 1∶1 motion scaling or 5∶1 motion scaling to complete endoscopic circle drawing had shorter completion time [1.68 (1.40, 2.17) min, 1.73 (1.47, 2.37) min VS 4.13 (2.27, 5.16) min, H=32.506, P<0.001], better trajectory deviation (0.50±0.11 mm, 0.46±0.11 mm VS 0.82±0.26 mm, F=38.999, P<0.001], and less workload [42.00 (30.00, 50.33) points, 43.33 (35.33, 54.00) points VS 52.67 (48.67, 63.33) points, H=20.056, P<0.001] than operating ordinary endoscope. In the advanced group, the operators operating RDES with 1∶1 or 5∶1 motion scaling to complete endoscopic circle drawing had longer completion time than operating ordinary endoscope [1.72 (1.37, 2.53) min, 1.57 (1.25, 2.58) min VS 1.15 (0.86, 1.58) min, H=13.233, P=0.001], but trajectory deviation [0.47 (0.13, 0.57) mm, 0.44 (0.39, 0.58) mm VS 0.52 (0.42, 0.59) mm, H=3.202, P=0.202] and workload (44.62±21.77 points, 41.24±12.57 points VS 44.71±17.92 points, F=0.369, P=0.693) were not different from those of the ordinary endoscope. Conclusion:The RDES enables remote control, greatly reducing the endoscopists' workload. Additionally, it gives full play to the cooperative motion function of the large and small endoscopic knobs, making the control more flexible. Finally, it increases motion scaling switching function to make the control of endoscope more flexible and more accurate. It is also easy for beginners to learn and master, and can shorten the training period. So it can provide the possibility of remote endoscopic control and fully automated robotic endoscope.
5.Establishment and application of measurement range of main blood quality indicators in provincial blood stations
Zixuan ZHANG ; Ying CHANG ; Xiaotong ZHANG ; Qingming WANG ; Yuan ZHANG ; Yue LIU ; Qinghua TIAN ; Ka LI ; Guorong LI ; Lixia CHEN ; Junhua SUN ; Yu KANG ; Pingchen HAN ; Xinyu ZHAO ; Song LI
Chinese Journal of Blood Transfusion 2024;37(8):918-926
Objective To obtain the monitoring measurement range of quality indicators of red blood cells,plasma and derivatives and leukocyte-reduced apheresis platelets provided by blood stations in Hebei province,explore the distribution of monitoring values and the change of monitoring level,so as to further strengthen the homogenization construction of quality control laboratories in blood stations in Hebei.Methods In 2023,the sampling data of 12 blood stations in Hebei from 2015 to 2022 were collected,scatter plots were made and the range markers were set,and the"mean±SD"line was taken as the upper limit and lower limit of the measurement range.In 2024,the monitoring values in 2023 were added,and the changes of two measurement ranges were compared to analyze the stability and overall level.Results Comparison of the measurement range from 2015 to 2022 and the measurement range from 2015 to 2023 showed that the standard deviation of the content of deleukocyte suspension of red blood cells-hemoglobin,washed erythrocyte-hemoglobin,washed erythrocyte-su-pernatant protein,cryoprecipitate coagulation factor-FⅧ,fresh frozen plasma-FⅧ,leukocyte-reduced apheresis platelets-leukocyte residue and leukocyte-reduced apheresis platelet-red blood cell concentration decreased from 8.132 to 7.993,6.252 to 6.104,0.273 to 0.267,57.506 to 56.276,0.920 to 0.892,0.653 to 0.644 and 2.653 to 2.603,respectively.The narrowing of the standard deviation range of the above items led to more concentrated monitoring values and reduced disper-sion.Comparison of the measurement range from 2015 to 2022 and the measurement range from 2015 to 2023 showed that the mean value of leukocyte residue of the deleukocyte suspension of red blood cells,hemoglobin content of the wash eryth-rocyte,protein content of supernatant of the wash erythrocyte,hemolysis rate of the wash erythrocyte,FⅧ content of the cryoprecipitate coagulation factor,plasma protein content of the fresh frozen plasma,FⅧ content of the fresh frozen plasma,platelet content of the leukocyte-reduced apheresis platelets changed from 0.362 to 0.476,44.915 to 44.861,0.280 to 0.283,0.137 to 0.142,133.989 to 133.271,60.262 to 60.208,1.301 to 1.277 and 3.036 to 3.033,respectively,and was closer to the national standard line,which reflects an increase in the number of unqualified monitoring values or values close to the national standard line in 2023.The long-term qualified rate of coagulation items was low,and no improvement has been ob-served.The stability of biochemical items has been enhanced but overall deviation has occurred,with the average value close to the national standard line.The possibility of subsequent testing failure has increased.The counting items showed no obvi-ous common characteristics.Conclusion The use of"mean±SD"in the analysis can visually display the distribution of mo-nitoring values of different items in Hebei,forming an indicator measurement range covering the past nine years.It shows the characteristics of each item,and provides reference for subsequent quality control laboratory data analysis of each blood sta-tions to takes active measures to improve the monitoring level.
6.miR-18a-5p Regulates Colorectal Cancer Proliferation and Progression by Targeting RORA
Yifeng CHEN ; Shuai WANG ; Mingming CHAI ; Di ZHANG ; Chunxia WANG ; Lixia ZHAO ; Honglai ZHANG ; Xiongfei YANG ; Weisheng ZHANG ; Tao WANG
Cancer Research on Prevention and Treatment 2024;51(8):667-677
Objective To investigate the mechanism and clinical significance of miR-18a-5p and retinoid acid receptor-related orphan receptor-α(RORA)in the proliferation and progression of colorectal cancer(CRC)cells.Methods The expressions of miR-18a-5p and RORA in CRC cells and tissues were detected via qRT-PCR,FISH,and IHC.Cell proliferation capability was detected through EdU and CFSE assay,cell apoptosis by flow cytometry assay,and cell migration and invasion abilities by cell scratch and Transwell invasion assays,respectively.The targeted regulation of miR-18a-5p on RORA was further verified via dual-luciferase reporter assay,cell function rescue test,RT-PCR,and Western blot assay.Finally,bioinformatics was used to explore the molecular mechanism of miR-18a-5p promoting malignant proliferation,invasion,and progression of CRC via regulating RORA.Results miR-18a-5p exhibited a high expression in CRC tissues and cells(P<0.05)and promoted the proliferation,migration,and invasion of CRC cells(P<0.05).In addition,RORA served as the target gene of miR-18a-5p,and its overexpression effectively reduced the promoting function of miR-18a-5p in the malignant biological phenotype of CRC cells(P<0.05).The expression of RORA in CRC tissues showed a significantly positively correlation with the infiltration of CD8+T cells and the expression of its surface marker protein CD8A.Conclusion The targeted regulation of RORA by miR-18a-5p promotes the proliferation and progression of CRC.The miR-18a-5p/RORA regulatory pathway possibly contributes to the immune microenvironment of CRC,which can be a potential therapeutic target for CRC.
7.Analysis of the influencing factors of abnormal blood pressure and electrocardiogram in occupational motor vehicle drivers
Yimu ZHENG ; Shuqiang LI ; Zanmei ZHAO ; Lixia GUO ; Yahong LI ; Li GUAN
Chinese Journal of Industrial Hygiene and Occupational Diseases 2024;42(11):821-825
Objective:To explore the influencing factors of abnormal blood pressure and electrocardiogram (ECG) in occupational motor vehicle drivers.Methods:In January 2024, a cluster sampling method was used to study 606 occupational motor vehicle drivers from a transportation service enterprise in Beijing who completed occupational health examination in 2023 in Peking University Third Hospital as observation group and 596 non-occupational motor vehicle drivers as control group. The data of personal history, occupational history, blood pressure and ECG were collected, and the effects of occupational motor vehicle driving on hypertension and ECG were analyzed by multivariate logistic regression.Results:The age of workers in the observation group was (34.1±7.8) years old, and the length of service was (7.0±7.1) years. The age of the control group was (33.8±7.6) years old, and the working age was (7.7±6.5) years. There was no significant difference in age and length of service between the two groups ( t=0.62, -1.90, P=0.538, 0.057). Systolic blood pressure (133.0±14.7) mmHg, diastolic blood pressure (83.7±11.6) mmHg, hypertension detection rate of 33.0% (200/606), ECG abnormality detection rate of 39.9% (242/606). They were significantly higher than those in the control group [ (127.8±14.4) mmHg, (77.5±11.0) mmHg, 24.7% (147/596), 31.0% (185/596) ], and the differences were statistically significant ( P<0.05). Multivariate logistic regression analysis showed that occupational motor vehicle driving were risk factors for hypertension and abnormal ECG ( OR= 1.210, 1.578; 95% CI: 1.145-1.231, 1.237-2.012; P<0.001) . Conclusion:Occupational motor vehicle driving may increase the risk of hypertension and abnormal ECG in workers.
8.PKM1 Regulates the Expression of Autophagy and Neuroendocrine Markers in Small Cell Lung Cancer
TANG CHENCHEN ; JIN YULONG ; ZHAO PEIYAN ; TIAN LIN ; LI HUI ; YANG CHANGLIANG ; ZHONG RUI ; LIU JINGJING ; MA LIXIA ; CHENG YING
Chinese Journal of Lung Cancer 2024;27(9):645-653
Background and objective Small cell lung cancer(SCLC)is known as recalcitrant cancer with high malignancy and heterogeneity.Immunotherapy has changed the treatment pattern of extensive-disease SCLC(ED-SCLC),but the beneficiary population is limited.Therefore,exploring new therapeutic strategies is an urgent clinical problem to be solved for SCLC.SCLC is characterized by highly active glycolytic metabolism and pyruvate kinase Ml(PKM1)is one of the isozymes of PK,an important rate-limiting enzyme in glycolysis pathway.Previous studies have shown that PKM1 is related to autophagy and drug sensitivity,however,how PKM1 regulates drug sensitivity in SCLC and its mechanism remain unclear.The aim of this study was to investigate the biological functions of PKM1 in SCLC,including its effects on proliferation,migra-tion,autophagy,drug sensitivity,and expression of neuroendocrine(NE)-related markers in SCLC.Methods Western blot was used to detect the expression level of PKM1 in SCLC cells.PKM1 gene-overexpressed SCLC cell lines were constructed by stable lentivirus transfection.Proliferation of cells and drug sensitivity were detected by MTT,and migration ability of cells was determined by Transwell.The level of autophagy was detected by flow cytometry.Western blot was used to determine the expression levels of NE-related proteins.Results PKM1 was differentially expressed among various SCLC cell lines,and was lower in H1092 cells(P<0.01).Compared with the control group,there was no significant difference in proliferation level of PKM1 overexpressing H1092 cell,but the migration ability was significantly increased(P<0.001),the drug sensitivity was re-duced,and the level of autophagy was inhibited(P<0.001).Additionally,overexpression of PKM1 could upregulate the expres-sion of non-neuroendocrine(non-NE)-related proteins(P<0.01)and decrease the expression of NE-related proteins(P<0.01).Conclusion PKM1 was differentially expressed in SCLC cell lines,and high expression of PKM1 did not affect the prolifera-tion,but affected the migration of SCLC cells.PKM1 might affect drug sensitivity by inhibiting autophagy and regulating the expression of NE markers.These results provide a theoretical basis for exploring the role of PKM1 in SCLC.
9.Genetic analysis of transcription factors in dopaminergic neuronal development in Parkinson’s disease
Yuwen ZHAO ; Lixia QIN ; Hongxu PAN ; Tingwei SONG ; Yige WANG ; Xiaoxia ZHOU ; Yaqin XIANG ; Jinchen LI ; Zhenhua LIU ; Qiying SUN ; Jifeng GUO ; Xinxiang YAN ; Beisha TANG ; Qian XU
Chinese Medical Journal 2024;137(4):450-456
Background::Genetic variants of dopaminergic transcription factor-encoding genes are suggested to be Parkinson’s disease (PD) risk factors; however, no comprehensive analyses of these genes in patients with PD have been undertaken. Therefore, we aimed to genetically analyze 16 dopaminergic transcription factor genes in Chinese patients with PD.Methods::Whole-exome sequencing (WES) was performed using a Chinese cohort comprising 1917 unrelated patients with familial or sporadic early-onset PD and 1652 controls. Additionally, whole-genome sequencing (WGS) was performed using another Chinese cohort comprising 1962 unrelated patients with sporadic late-onset PD and 1279 controls.Results::We detected 308 rare and 208 rare protein-altering variants in the WES and WGS cohorts, respectively. Gene-based association analyses of rare variants suggested that MSX1 is enriched in sporadic late-onset PD. However, the significance did not pass the Bonferroni correction. Meanwhile, 72 and 1730 common variants were found in the WES and WGS cohorts, respectively. Unfortunately, single-variant logistic association analyses did not identify significant associations between common variants and PD. Conclusions::Variants of 16 typical dopaminergic transcription factors might not be major genetic risk factors for PD in Chinese patients. However, we highlight the complexity of PD and the need for extensive research elucidating its etiology.
10.Monitoring results of human brucellosis prevention and control project in Gansu Province from 2016 to 2022
Jie WANG ; Dingsheng WANG ; Lixia NIU ; Hong GUAN ; Xiaoyan ZHOU ; Qi ZHAO
Chinese Journal of Endemiology 2024;43(7):580-585
Objective:To analyze the monitoring results of human brucellosis prevention and control project in Gansu Province, in order to provide reference for the next revision of prevention and control plans.Methods:The data from the "China Disease Prevention and Control Information System" in Gansu Province from 2016 to 2022 and the annual data of human brucellosis cases reported by the active monitoring reports in various project counties (districts) were input into Excel 2016 software and a database was established. The epidemiological situation of brucellosis, the coverage of brucellosis prevention and control projects, the number of detected cases and health education were analyzed and compared by descriptive epidemiological method.Results:From 2016 to 2022, 70 to 82 out of 86 counties (districts) in Gansu Province were found to have human outbreaks of brucellosis, with brucellosis prevention and control projects covering 17 to 43 counties (districts). A total of 19 855 cases of human brucellosis were reported online in the province, with an average annual incidence of 11.07/100 000 and an annual incidence ranging from 6.03/100 000 to 20.89/100 000. There was a statistically significant difference in incidence among years (χ 2 = 5 264.84, P < 0.001). Through active monitoring, a total of 433 303 cases of brucellosis (tiger red plate agglutination test, RBT) were initially screened in project counties (districts) throughout the province, with 13 277 positive cases and a positive rate of 3.06% (13 277/433 303). Then the laboratory confirmed test (test-tube agglutination test, SAT) for brucellosis was carried out, with 9 967 positive cases and a positive rate of 2.30% (9 967/433 303). The infection rate of brucellosis in the population (SAT positive) was compared between different years, and the difference was statistically significant (χ 2 = 600.12, P < 0.001). In the project counties (districts), 7 481 confirmed cases of brucellosis were detected by active surveillance, and 15 794 cases were reported online, accounting for 47.37% (7 481/15 794) of the total number of cases reported online. The average awareness rate of brucellosis knowledge among medical personnel increased from 70.49% before training to 88.89% after training. The average awareness rate of brucellosis prevention and control knowledge among high-risk groups increased from 63.49% before health education to 89.05% after health education, and the behavior formation rate increased from 62.84% to 86.04%. Conclusions:From 2016 to 2022, the epidemic scope of human brucellosis in Gansu Province has been expanding year by year, and the coverage of prevention and control project is relatively small. The proportion of cases detected through active screening is relatively low. It is necessary to increase special funding investment, expand project coverage, strengthen high-risk group screening, education and behavioral intervention, and follow-up management of acute stage patient, so as to identify patients as early as possible and curb the upward trend of the epidemic.

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