1.Thermal dose effect of regional radiofrequency hyperthemia on metaphase and advanced stage tumor
Yishan WANG ; Qinwen WANG ; Xifeng JIA ; Renqun GE ; Na SHENG
Chinese Journal of Tissue Engineering Research 2007;11(44):9011-9015
BACKGROUND: Foreign scholars use thermotherapy, a new pathway for synthetic therapy of tumor, to perform hyperpyrexia combined with chemical drug radiotherapy of intraperitoneal infiltration and metastasis or to study on the therapeutic effect of metaphase and advanced stage tumor. Especially, establishing thermal biology and thermal dosiology is a scientific and quantified track for synthetic therapy of thermal radiotherapy, thermal chemotherapy and hyperthermal perfusion of tumor.OBJECTIVE: To analyze the thermal dose effect of regional radiofrequency (RF) hyperthemia combined with radiotherapy, chemotherapy and thermal perfusion on metaphase and advanced stage tumor.DESIGN: Controlled observation.SETTING: Key Department of Traditional Chinese and Western Medicine for Tumor, the 107 Hospital of Chinese PLA (General Center for Non-traumatic Treatment and Diagnosis of Tumor).PARTICIPANTS: Totally 1 455 patients with metaphase and advanced-stage tumor admitted to the General Center for Non-traumatic Treatment and Diagnosis of Tumor, the 107 Hospital of Chinese PLA between June and September 2006 who received conservative palliative treatment in the Department of Internal Medicine were recruited in this study. They were all confirmed by pathology and imageology. ECOG was scored 2 to 4 points. Informed consents of detection and treatment were obtained from all the involved patients. The study was approved by the Hospital Ethics Committee.According to the therapeutic regimen, the patients were assigned into thermal perfusion group (n =53), thermal radiotherapy group (n =874), thermal chemotherapy group (n =458) and simple hyperthemia group (n =70).METHODS: After admission, patients in each group were performed peritoneal and pelvic cavity perfusion,intensity-modulated radiation therapy, routine chemotherapy and integrated traditional and western medicine palliative therapy, respectively. Meanwhile, they received RF hyperthemia using in vitro endogenic magnetic field hyperthermia system. A thermocouple was placed in the abdominal cavity. Temperature at 3 different sites in the abdominal cavity was collected, and meanwhile two different sites for measuring temperature at rectum and external acoustic meatus were monitored. The maximal temperature (Tmax), minimal temperature (Tmin) and the average temperature (Tave) of therapeutic target were recorded. 40 ℃/min was used as thermal dose, thermal perfusion was performed once a week, and RF hyperthemia was conducted twice a week, 60 minutes once. Target temperature was 39.5 to 43 ℃, and the thermal dose of 40 ℃/min was calculated out. Intensity-modulated radiation therapy was conducted within 1 hour before heating at (3-5)Gy/time, 3 to 4 times a week. Total dose was DT 30 to 50Gy. Thermal perfusion was conducted 2 to 3 times a week, and intensity-modulated radiation therapy was conducted once to twice a week and 6 to 8 times a course of treatment. The thermal effect of each patient was analyzed at different temperature and different diseases.MAIN OUTCOME MEASURES: ① To analyze the effect of effective thermal dose. ② To evaluate the therapeutic effect and the improvement of quality of life according to World Health Organization (WHO) objective therapeutic effect evaluation criteria and Zubrod-ECOG-WHO scores. ③To observe the changes in abdominal dropsy.RESULTS: Altogether 1 455 patients with metaphase and advanced stage participated in the final analysis. ①After perfusion, body temperature was over 39.5 ℃ in most cases after 15-minute warming, over 40.0 ℃ after another 25-minute warming, over 41.0 ℃ after additional 35-minute arming, and even to 43.0 ℃ after frequent such a thermal therapy. Temperature over 41 ℃ was found in 91 cases, at 40 ℃-40.9 ℃ in 414 cases and at 39.5 ℃-39.9 ℃ in 950 cases. ② The thermal effect of 40 ℃/min could obviously improve the therapeutic effects of graded intensity-modulated radiation therapy, low-dose chemotherapy and thermal perfusion group. The total effective rate of thermal perfusion group, thermal radiotherapy group, thermal chemotherapy group and simple hyperthemia group was 81.6%, 81.9%, 80% and 50%, respectively. The clinical therapeutic effect of 40 ℃-40.9 ℃ and 39.5 ℃-39.9 ℃ in the thermal perfusion group, thermal radiotherapy group and thermal chemotherapy group was significantly better than that in the simple hyperthemia group (P < 0.05). ③ Comparison of Zubrod-ECOG-WHO score of patients before and after therapy: After therapy, Zubrod-ECOG-WHO score was enhanced in 76.3% patients. ④The changes in abdominal dropsy of patients before and after therapy: After therapy, abdominal dropsy changed in 75% patients.⑤The therapeutic effects of different diseases at different temperature: For the same disease, the therapeutic effects over 41 ℃ and at 40 ℃-40.9 ℃ were significantly different from those at 39.5 ℃-39.9 ℃(P < 0.05); However, the therapeutic effects over 41 ℃ were not significantly different from those at 40 ℃-40.9 ℃ (P > 0.05).CONCLUSION: ①The effects of regional RF hyperthemia combined with intensity-modulated radiation therapy are confirmed in the treatment of metaphase and advanced-stage of tumor. ② The therapeutic effects strengthen correspondingly with 40 ℃/min thermal dose increase or temperature increase.
2.Optimized Extraction of Total Saponins from Platycodon grandiflorum
Xifeng LI ; Shuo AN ; Weixiao ZHANG ; Youxu WANG ; Yongyan JIA
Herald of Medicine 2015;(10):1347-1351
Objective To optimize the process of extracting total saponins from Platycodon grandiflorum by orthogonal experimental design and central composite design-response surface method. Methods Independent variables were concentration of ethanol, reflux extraction time, reflux time and solvent fold. Dependent variables were extraction rate of total saponins in Platycodon grandiflorum and the yield of dry extract.Linear or nonlinear mathematic models were used to estimate the relationship between independent and dependent variables. Results The result of the orthogonal experimental design was 70%ethanol, 180 min for reflux, 6 fold of solvent and 2 times for extraction. The result of central composite design-response surface method was 70% ethanol, 140 min for reflux, 10 fold of solvent and 2 times for extraction. Conclusion The central composite design-response surface method is better than orthogonal experimental design in studying extraction process of Platycodon grandiflorum, which provides basis for feasibility of application of central composite design-response surface method in optimization of extraction process of Chinese traditional medicine.
3.Study of coupled plasma filtration adsorption therapy for patients with severe infection and multiple organ dysfunction syndromes
Xiaoli LI ; Luyi IU ; Jing HU ; Yafeng LIANG ; Meifeng LI ; Xinghan TIAN ; Xifeng WANG ; Qingxia YU ; Jia LIU
Chinese Journal of Emergency Medicine 2017;26(8):919-923
Objective To investigate the effect of coupled plasma filtration adsorption (CPFA) on plasma cytokines:TNF-α,IL-1β,IL-6,cellular immunity,blood lactate acid concentration,heart rate,respiration rate,oxygenation index,hemodynamics,blood cells counts,and prognosis in patients with multiple organ dysfunction syndromes (MODS).Methods This was a prospective,randomized clinical trial in 45 patients diagnosed as MODS.Patients were randomly assigned to hemoperfution with resin adsorption (HP) + continuous venous-venous hemofiltration (CVVH) group,CPFA group and CVVH group.The general clinical data,APACHE Ⅱ score,number of failure organ and previous mentioned biomarkers were documented.Blood samples were collected before and after blood filtration with any one of these procedures.The plasma samples were isolated and stored with frozen at-60 ℃.Data were statistically analyzed with SPSS 13.0 version software.Results In CPFA group,plasma cytokines,TNF-α、IL-1β、IL-6,decreased markedly after plasma adsorption for two hours (P < 0.01);and plasma concentrations of IL-6 were further descended after subsequent CVVH for 10 hours (P < 0.05).In HP + CVVH group,plasma cytokines,TNF-α、IL-1β、IL-6,decreased markedly after HP (P < 0.01),and plasma concentrations of IL-6 were further descended after subsequent CVVH for 10 hours (P < 0.05).In CVVH group,plasma cytokines,TNF-α、IL-1β、IL-6,decreased after CVVH for 12 hours (P < O.05).Blood lactate acid concentration,heart rate,respiration rate,oxygenation index,T-lymphocytes subgroups (CD3 +,CD4 +,CD8 +,CD4 +/CD8 + ratio),clinical symptoms were improved and dose of vasoactive agent was reduced in the patients of three groups without differences among them.The counts of red blood cells,white blood cells and platelets after CPFA and CVVH showed no significant changes.There was no significant difference in blood cell counts between CPFA and CVVH groups.After HP + CVVH,there was a trend of decrease in platelet count (P < 0.05).Platelet counts were significanfly higher in patients treated with CPFA and CVVH group than those in patients treated with HP + CVVH group (P < 0.05).There were 6 patients died in HP + CVVH group,6 patients died in CPFA group and 5 patients died in CVVH group within 28days.Conclusions The comparison of efficacy of blood filtration among 3 modalities of HP + CVVH,CPFA and CVVH showed CPFA had higher capacity of Inflammatory medium scavenging than CVVH,and had less damage effect on blood visible component,especially on platelet compared with HP + CVVH.CPFA was an effective and safety modality in the treatment of the patients with multiple organ dysfunction syndrome.
4.Experimental study on the prevention of bone loss by deferoxamine in type 1 diabetic mice with osteoporosis
Dong ZHANG ; Peng ZHAO ; Jia JIN ; Xifeng JIANG ; Honghui SONG ; Peng JIA ; Youjia XU ; Lianfu DENG
Chinese Journal of Endocrinology and Metabolism 2019;35(1):67-72
Objective To observe the effect of a hypoxia mimicking agent deferoxamine (DFO) on the mineral density,volume,architecture,strength,and metabolism of the bones in type 1 diabetic mice withosteoporosis.Methods Type 1 diabetic mice model was established by intraperitoneal injections of streptozotocin.The mice were divided into control (normal mice),diabetes mellitus,and DFO groups.Micro-CT was used to analyze the bone mineral density,volume,architecture,and strength of the trabecule in the distal part of femurs.Three point bending test was carried out to evaluate the bone strength.Hematoxylin and eosin (HE) staining was performed to observe the alteration in the number of osteoblasts.Real-time PCR was used to detect the mRNA expressions of Runt-related gene 2 (Runx-2),osteoclacin,and tartrate resistant acid phosphatase (TRAP) in tibias.Western blot was used to detect the protein expressions of Hypoxia-inducible factor-1α(HIF-1α) and vascular endothelial growth factor (VEGF) in tibias.Results There was a decrease in mineral density,volume,strength of bones as well as deteriorated trabecular microarchitecture in diabetic mice as compared to control mice,which were partially improved by DFO treatment.Moreover,DFO treatment increased the number of osteoblasts and mRNA expression levels of Runx-2,osteoclacin,TRAP,as well as protein expression levels of HIF-1 α and VEGF(P<0.05).Conclusion Bone loss could be partially prevented by DFO treatment in type 1 diabetic osteoporosis mice,which might be ascribed to increased bone formation via stimulating hypoxia inducible factor singnaling pathway.
5.Evaluation of nursing effect of enhanced recovery after surgery model in elderly patients with hip fracture
Honghui SONG ; Peng ZHANG ; Wei XU ; Wei WANG ; Xifeng JIANG ; Youjia XU ; Jia JIN
Chinese Journal of Trauma 2021;37(9):825-832
Objectives:To investigate the nursing effect of perioperative enhanced recovery after surgery(ERAS)management model in elderly patients with hip fracture.Methods:A retrospective case-control study was conducted to analyze the clinical data of 94 elderly patients with hip fracture admitted to Second Affiliated Hospital of Soochow University from July 2017 to June 2018,including 24 males and 70 females aged 76-98 years[(83.7±5.4)years]. There were 54 patients with intertrochanteric fracture and 40 patients with femoral neck fracture. Surgical method was proximal femoral nail antirotation(PFNA)fixation or artificial hip arthroplasty. A total of 44 patients were managed by ERAS(enhanced recovery group)and 50 patients by traditional nursing(traditional rehabilitation group). The off-bed time was compared between the two groups from aspects of different fracture sites,bone mineral density and causes of injury. The visual analogue scale(VAS)was tested preoperatively and at postoperative days 1,3 and 7. The complications were recorded at postoperative 1 month. The activity of daily living(ADL)score was assessed preoperatively and at postoperative 1 week,1 month and 3 months. The Harris hip score was assessed at postoperative 1 week,1 month,3 months and at the last follow-up. The length of hospital stay and death at postoperative 3 months and at the last follow-up were recorded.Results:All patients were followed up for 12-24 months[(17.7±6.2)months]. In enhanced recovery group,the off-bed time of patients with different fracture sites(femoral neck,femoral intertrochanter),bone mineral density(>-2.5 SD,≤-2.5 SD)and causes of injury(falls,traffic accidents and others)were markedly shortened as compared with traditional rehabilitation group( P<0.01). There was no significant difference in VAS between the two groups before operation( P>0.05). However,the VAS in enhanced recovery group was(3.4±0.9)points,(2.7±0.5)points,(1.7±0.6)points at postoperative days 1,3 and 7,significantly lower than that in traditional rehabilitation group[(4.3±1.1)points,(3.5±0.5)points,(2.7±0.9)points]( P<0.01). One month after operation,the incidence of pulmonary infection was 0% in enhanced recovery group and 28%(14/50)in traditional rehabilitation group( P<0.01). While there showed no significant differences in incidences of cardiovascular system,nervous system,urinary tract infection,lower limb deep vein thrombosis,impaired liver and kidney function,anemia,electrolyte disorder or hypoalbuminemia between the two groups( P>0.05). There was no significant difference in preoperative ADL score between the two groups( P>0.05). The ADL score in enhanced recovery group was(37.0±6.6)points,(70.1±8.4)points,(86.2±9.3)points at postoperative 1 week,1 month and 3 months,significantly higher than that in traditional rehabilitation group[(26.5±10.4)points,(50.1±11.4)points,(70.7±9.0)points]( P<0.01). The Harris hip score in enhanced recovery group was(80.9±8.6)points at postoperative 1 month,significantly higher than that in traditional rehabilitation group[(71.1±9.2)points]( P<0.01). There were no significant differences in Harris hip score between the two groups at postoperative 1 week,3 months and at the last follow-up( P>0.05). The length of hospital stay was(4.7±2.4)days in enhanced recovery group,significantly shorter than(7.8±3.9)days in traditional rehabilitation group( P<0.01). The enhanced recovery group showed no death within 3 months after operation and 2 deaths[5%(2/44)]at the last follow-up,while the traditional rehabilitation group revealed 4 deaths[8%(4/50)]within 3 months after operation. There was no significant difference in the mortality between the two groups until the last follow-up( P>0.05). Conclusion:For elderly patients with hip fracture,perioperative ERAS management model can effectively shorten periods in bed,relieve postoperative pain,reduce incidence of postoperative pulmonary infection,accelerate recovery of hip function,improve quality of life,shorten length of hospitalization and promote early recovery.
6.FOLFIRINOX as a first line therapy in locally advanced pancreatic cancer and borderline resectable pancreatic cancer: a Meta-analysis
Xifeng XU ; Song ZHENG ; Zhen WANG ; Yuan QIAN ; Changku JIA
Chinese Journal of Hepatobiliary Surgery 2018;24(1):38-42
Objective To evaluate the efficacyof the first line chemotherapy FOLFIRINOX (5-Fu,Leucovorin calcium,Irinotecan,Oxaliplatin) as the treatment of pancreatic cancer.Methods Pertinent studies were identified from the PubMed,Cochrane Library and EMBASE.The outcomes were resection rate and radical (R0) resection rate were analyzed.Data were expressed as weighted pooled proportions with 95% confidence intervals (95% CI).Results There were thirteen studies with 408 patients with LAPC and BRPC included.After the treatment,42.0% (95% CI:28.0% ~56.0%) tumorswere resected and 41.0% (95% CI:37.0% ~45.0%) were underwentR0 resection,and median overall survival ranged from 15.5 to 34.5 months,median progression-free survival ranged from 10.0 to 17.8 months.Conclusion The meta-analysis shows that down-staging after first line FOLFIRINOX-based therapy is noticeable in patients with borderline resectable/unresectable PC,and the adverse events were in control.
7.Mechanism study of chlorogenic acid alleviating macrophage activation
Wei ZHENG ; Jing LANG ; Xifeng HUANG ; Rui XIAO ; He BAI ; Ji JIA
China Pharmacy 2023;34(21):2601-2607
OBJECTIVE To observe the effects of chlorogenic acid on the activation of macrophage induced by lipopolysaccharide (LPS), and to explore the role of triggering receptors expressed on myeloid cells-2 (TREM2) in the action. METHODS To find a suitable LPS concentration, the cells were cultured with 1, 10 and 100 ng/mL LPS for 24 h. The level of interleukin 6 (IL-6) in the cell culture supernatant and protein expression of inducible nitric oxide synthase (iNOS) in the cells were detected. To search for a suitable chlorogenic acid concentration, the cells were divided into control group, LPS group and three chlorogenic acid (0.01, 0.1 and 1 μmol/L)+LPS groups. The levels of tumor necrosis factor α (TNF-α) and IL-1β in the cell culture supernatant, the protein expressions of iNOS and TREM2 in the cells and cell viability were detected. To observe the effects of TREM2 in chlorogenic acid alleviating macrophage activation, TREM2-small interfering RNA (TREM2-siRNA) was taken to intervene in TREM2 protein expression. The cells were divided into control group, LPS group, chlorogenic acid+LPS group, TREM2-siRNA+chlorogenic acid+LPS group and SC-siRNA+chlorogenic acid+LPS group. After 24 h incubation, the levels of TNF- α and IL-1β in the cell culture supernatant and protein expressions of TREM2, iNOS and nuclear factor κB p65 (NF-κB p65) in the cells were detected. RESULTS 10 ng/mL LPS promoted IL-6 release and increased iNOS protein expression, and 10 ng/mL LPS was taken in the next experiments. Compared with the LPS group, 0.1 μmol/L chlorogenic acid decreased TNF-α jiaji1981@126.com and IL-1β levels, and down-regulated iNOS expression,meanwhile increased TREM2 expression without effect on cell viability, and 0.1 μmol/L chlorogenic acid was taken in the next experiments. Compared with the control group, the protein expressions of iNOS and NF- κB p65 in the LPS group were significantly increased (P<0.05); compared with the LPS group, the protein expressions of iNOS and NF- κB p65 in the chlorogenic acid+LPS group were significantly decreased, the protein expressions of TREM2 was significantly increased (P< 0.05); compared with the chlorogenic acid+LPS group, the protein expressions of iNOS and NF-κB p65 of TREM2-siRNA+ chlorogenic acid+LPS group were significantly increased, the protein expressions of TREM2 was significantly decreased (P<0.05). TREM2-siRNA could significantly reverse the above effects of chlorogenic acid, while SC-siRNA did not significantly affect the above anti-inflammatory effects of chlorogenic acid. CONCLUSIONS Chlorogenic acid can inhibit the LPS-induced macrophage activation, and its anti-inflammatory may be mediated by TREM2 protein.
8. Relationship between work-related musculoskeletal disorders and ergonomic factor load in shipyard workers
Ying QU ; Xifeng CHEN ; Wei ZHANG ; Chengbin ZHENG ; Xueyan ZHANG ; Ning JIA ; Siwu ZHONG ; Qing XU ; Xi ZHANG ; Zhongxu WANG
China Occupational Medicine 2020;47(03):260-267
OBJECTIVE: To assess the effect of ergonomic factor load on work-related musculoskeletal disorders(WMSDs) in shipyard workers. METHODS: A total of 751 shipyard workers were selected as the research subjects using judgment sampling method. The exposure level of adverse ergonomic factors was assessed using the Quick Exposure Check method. The prevalence of WMSDs was investigated using the revised Musculoskeletal Disorders Investigating Questionnaire of our research group, and the relationship between them was analyzed. RESULTS: The proportions of high or very high level of work load exposure to the neck, back, shoulder and hand in shipyard workers from high to low were 66.4%, 63.5%, 59.8% and 43.7%(P<0.01) respectively. The proportions of occupational stress, driving, vibration and working rhythm at high or very high exposure level were 20.0%, 4.1%, 22.9% and 3.2%, respectively. The prevalence of WMSDs in four body parts of shipyard workers from high to low was the back, neck, hand and shoulder(the prevalence were 44.2%, 31.2%, 26.9% and 26.6%, respectively, P<0.01). After excluding the influence of confounding factors, multiple logistic regression analysis showed that the higher the labor load exposure level and longer of the vibration tool using, the higher the risk of shoulder WMSDs [odds ratio(OR) and 95% confidence interval(CI) were 1.25(1.04-1.51) and 1.33(1.05-1.69), respectively, P<0.05]. The higher the level of occupational stress, the higher the risk of back and neck WMSDs [OR(95%CI) was 1.29(1.05-1.58) and 1.42(1.15-1.77), respectively, P<0.05]. CONCLUSION: There was a dose-effect relationship between the exposure level of shoulder load, the time of using vibration tools and the shoulder WMSDs, and there was a dose-effect relationship between the occupational stress level and the WMSDs in the back and neck.
9.Impact of Wuhan lockdown on the spread of COVID-19 in China: a study based on the data of population mobility.
Shu LI ; Qinchuan WANG ; Sicong WANG ; Junlin JIA ; Zilong BIAN ; Changzheng YUAN ; Sisi WANG ; Xifeng WU ; Shuyin CAO ; Chen CHEN ; Xiaolin XU ; Yuanqing YE ; Hao LEI ; Wenyuan LI ; Kejia HU
Journal of Zhejiang University. Medical sciences 2021;50(1):61-67
This study aimed to quantitatively assess the effectiveness of the Wuhan lockdown measure on controlling the spread of coronavirus diesase 2019 (COVID-19). : Firstly,estimate the daily new infection rate in Wuhan before January 23,2020 when the city went into lockdown by consulting the data of Wuhan population mobility and the number of cases imported from Wuhan in 217 cities of Mainland China. Then estimate what the daily new infection rate would have been in Wuhan from January 24 to January 30th if the lockdown measure had been delayed for 7 days,assuming that the daily new infection in Wuhan after January 23 increased in a high,moderate and low trend respectively (using exponential, linear and logarithm growth models). Based on that,calculate the number of infection cases imported from Wuhan during this period. Finally,predict the possible impact of 7-day delayed lockdown in Wuhan on the epidemic situation in China using the susceptible-exposed-infectious-removed (SEIR) model. : The daily new infection rate in Wuhan was estimated to be 0.021%,0.026%,0.029%,0.033% and 0.070% respectively from January 19 to January 23. And there were at least 20 066 infection cases in Wuhan by January 23,2020. If Wuhan lockdown measure had been delayed for 7 days,the daily new infection rate on January 30 would have been 0.335% in the exponential growth model,0.129% in the linear growth model,and 0.070% in the logarithm growth model. Correspondingly,there would have been 32 075,24 819 and 20 334 infection cases travelling from Wuhan to other areas of Mainland China,and the number of cumulative confirmed cases as of March 19 in Mainland China would have been 3.3-3.9 times of the officially reported number. Conclusions: Timely taking city-level lockdown measure in Wuhan in the early stage of COVID-19 outbreak is essential in containing the spread of the disease in China.
COVID-19
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China/epidemiology*
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Cities
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Communicable Disease Control
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Humans
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SARS-CoV-2
10.Predicting COVID-19 epidemiological trend by applying population mobility data in two-stage modeling.
Shu LI ; Qinchuan WANG ; Sicong WANG ; Junlin JIA ; Changzheng YUAN ; Sisi WANG ; Xifeng WU ; Shuyin CAO ; Chen CHEN ; Xiaolin XU ; Yuanqing YE ; Zhengping XU ; Hao LEI ; Zhijun YING ; Kejia HU ; Vermund STEN H
Journal of Zhejiang University. Medical sciences 2021;50(1):68-73
:To predict the epidemiological trend of coronavirus disease 2019 (COVID-19) by mathematical modeling based on the population mobility and the epidemic prevention and control measures. : As of February 8,2020,the information of 151 confirmed cases in Yueqing,Zhejiang province were obtained,including patients' infection process,population mobility between Yueqing and Wuhan,etc. To simulate and predict the development trend of COVID-19 in Yueqing, the study established two-stage mathematical models,integrating the population mobility data with the date of symptom appearance of confirmed cases and the transmission dynamics of imported and local cases. : It was found that in the early stage of the pandemic,the number of daily imported cases from Wuhan (using the date of symptom appearance) was positively associated with the number of population travelling from Wuhan to Yueqing on the same day and 6 and 9 days before that. The study predicted that the final outbreak size in Yueqing would be 170 according to the number of imported cases estimated by consulting the population number travelling from Wuhan to Yueqing and the susceptible-exposed-infectious-recovered (SEIR) model; while the number would be 165 if using the reported daily number of imported cases. These estimates were close to the 170,the actual monitoring number of cases in Yueqing as of April 27,2020. : The two-stage modeling approach used in this study can accurately predict COVID-19 epidemiological trend.
COVID-19
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China/epidemiology*
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Disease Outbreaks
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Humans
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Models, Theoretical
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Pandemics
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SARS-CoV-2