Over the years,the Shaying River Basin has experienced frequent instances of river pollution.The presence of numerous critical pollutant discharge enterprises and sewage-treatment plants in the vicinity of the Shaying...Over the years,the Shaying River Basin has experienced frequent instances of river pollution.The presence of numerous critical pollutant discharge enterprises and sewage-treatment plants in the vicinity of the Shaying River has transformed it a major tributary with relatively serious pollution challenge within the upper reaches of Huaihe River Basin.To study the sources of manganese(Mn),chromium(Cr),nickel(Ni),arsenic(As),cadmium(Cd)and lead(Pb)in Shaying River water,123 sets of surface water samples were collected from 41 sampling points across the entire basin during three distinct phases from 2019 to 2020,encompassing normal water period,dry season and wet season.The primary origins of heavy metals in river water were determined by analyzing the heavy metal contents in urban sewage wastewater,industrial sewage wastewater,groundwater,mine water,and the heavy metal contributions from agricultural non-point source pollution.The analytical findings reveal that Mn primarily originates from shallow groundwater used for agricultural irrigation,While Cr mainly is primarily sourced from urban sewage treatment plant effluents,coal washing wastewater,tannery wastewater,and industrial discharge related to metal processing and manufacturing.Ni is mainly contributed by urban sewage treatment plant effluents and industrial wastewater streams associated with machinery manufacturing and metal processing.Cd primarily linked to industrial wastewater,particularly from machinery manufacturing and metal processing facilities,while Pb is predominantly associated with urban sewage treatment plant effluents and wastewater generated in Pb processing and recycling wastewater.These research provides a crucial foundation for addressing the prevention and control of dissolved heavy metals at their sources in the Shaying River.展开更多
BACKGROUND The case of Crohn's disease involving the duodenum is rare,and its surgical management requires a thorough understanding.AIM To investigate the surgical management of duodenal Crohn’s disease.METHODS W...BACKGROUND The case of Crohn's disease involving the duodenum is rare,and its surgical management requires a thorough understanding.AIM To investigate the surgical management of duodenal Crohn’s disease.METHODS We systematically reviewed patients diagnosed with duodenal Crohn's disease who underwent surgery in the Department of Geriatrics Surgery of the Second Xiangya Hospital of Central South University from January 1,2004,to August 31,2022.The general information,surgical procedures,prognosis,and other information of these patients were collected and summarized.RESULTS A total of 16 patients were diagnosed with duodenal Crohn’s disease,where 6 cases had primary duodenal Crohn’s disease,and 10 had secondary duodenal Crohn’s disease.Among patients with primary disease,5 underwent duodenal bypass and gastrojejunostomy,and 1 received pancreaticoduodenectomy.Among those with a secondary disease,6 underwent closure of duodenal defect and colectomy,3 received duodenal lesion exclusion and right hemicolectomy,and 1 underwent duodenal lesion exclusion and double-lumen ileostomy.CONCLUSION Crohn's disease involving the duodenum is a rare condition.Different surgical management should be applied for patients with Crohn's disease presenting with different clinical manifestations.展开更多
AIM To examine the impact of aging on the short-term outcomes following pancreatic resection(PR) in elderly patients.METHODS A retrospective cohort study using prospectively collected data was conducted at the China N...AIM To examine the impact of aging on the short-term outcomes following pancreatic resection(PR) in elderly patients.METHODS A retrospective cohort study using prospectively collected data was conducted at the China National Cancer Center. Consecutive patients who underwent PR from January 2004 to December 2015 were identifiedand included. ‘Elderly patient' was defined as ones age 65 and above. Comorbidities, clinicopathology, perioperative variables, and postoperative morbidity and mortality were compared between the elderly and young patients. Univariate and multivariate analyses were performed using the Cox proportional hazard model for severe postoperative complications(grades Ⅲb-Ⅴ).RESULTS A total of 454(63.4%) patients were < 65-yearsold and 273(36.6%) patients were ≥ 65-yearsold, respectively. Compared to patients < 65-yearsold, elderly patients had worse American Society of Anesthesiologists scores(P = 0.007) and more comorbidities(62.6% vs 32.4%, P < 0.001). Elderly patients had more severe postoperative complications(16.8% vs 9.0%, P = 0.002) and higher postoperative mortality rates(5.5% vs 0.9%, P < 0.001). In the multivariate Cox proportional hazards model for severe postoperative complications, age ≥ 65 years [hazard ratio(HR) = 1.63; 95% confidence interval(CI): 1.18-6.30], body mass index ≥ 24 kg/m^2(HR = 1.20, 95%CI: 1.07-5.89), pancreaticoduodenectomy(HR = 4.86, 95%CI: 1.20-8.31) and length of operation ≥ 241 min(HR = 2.97; 95%CI: 1.04-6.14) were significant(P = 0.010, P = 0.041, P = 0.017 and P = 0.012, respectively).CONCLUSION We found that aging is an independent risk factor for severe postoperative complications after PR. Our results might contribute to more informed decision-making for elderly patients.展开更多
AIM to evaluate the association of body mass index(b MI) with the overall survival of pancreatic ductal adenocarcinoma(PDAC) patients.METHODS A retrospective analysis of PDAC patients diagnosed in the National Cancer ...AIM to evaluate the association of body mass index(b MI) with the overall survival of pancreatic ductal adenocarcinoma(PDAC) patients.METHODS A retrospective analysis of PDAC patients diagnosed in the National Cancer Center of China between January 1999 and December 2014 was performed. these patients were categorized into four b MI groups(< 18.5, 18.5-22.9, 23-27.4 and ≥ 27.5 kg/m2). χ2 tests for comparison of the proportions of categorical variables, and Student's t-test or Mann-Whitney test for continuous variables were employed. Survival analysis was performed with the Kaplan-Meyer method. their HRs of mortality and 95%CIs were estimated using the Cox proportional hazards model.RESULTS With a median age of 59.6 years(range: 22.5-84.6 years), in total 1783 PDAC patients were enrolled in this study. their mean usual b MI was 24.19 ± 3.53 for the whole cohort. More than half of the patients(59.3%) experienced weight loss during the disease onset and progression. Compared with healthy-weight individuals, newly diagnosed patients who were overweight or obese had more severe weight loss during their disease onset and progression(P < 0.001). Individuals who were overweight or obese were associated with positive smoking history(P < 0.001). A significant difference in comorbidity of diabetes(P = 0.044) and coronary artery disease(P < 0.001) was identified between high b MI and normal-weight patients. After a median follow-up of 8 mo, the survival analysis showed no association between b MI and the overall survival(P = 0.90, n = 1783). When we stratified the whole cohort by pancreatic cancer stage, no statistically significant association between b MI and overall survival was found for resectable(P = 0.99, n = 217), unresectable locally advanced(P = 0.90, n = 316) and metastatic patients(P = 0.88, n = 1250), respectively. the results did not change when we used the b MI at diagnosis.CONCLUSION Our results showed no significance of b MI for the overall survival of PDAC patients.展开更多
AIM: To examine the impact of body mass index(BMI)on outcomes following pancreatic resection in the Chinese population.METHODS: A retrospective cohort study using prospectively collected data was conducted at the Canc...AIM: To examine the impact of body mass index(BMI)on outcomes following pancreatic resection in the Chinese population.METHODS: A retrospective cohort study using prospectively collected data was conducted at the Cancer Hospital of the Chinese Academy of Medical Sciences, China National Cancer Center. Individuals who underwent pancreatic resection between January2004 and December 2013 were identified and included in the study. Persons were classified as having a normal weight if their BMI was < 24 kg/m2 and overweight/obese if their BMI was ≥ 24 kg/m2 as defined by the International Life Sciences Institute Focal Point in China. A χ 2 test(for categorical variables) or a t test(for continuous variables) was used to examine the differences in patients' characteristics between normal weight and overweight/obese groups. Multiple logistic regression models were used to assess the associationsof postoperative complications, operative difficulty,length of hospital stay, and cost with BMI, adjusting for age, sex, and type of surgery procedures.RESULTS: A total of 362 consecutive patients with data available for BMI calculation underwent pancreatic resection for benign or malignant disease from January1, 2004 to December 31, 2013. Of the 362 patients,156 were overweight or obese and 206 were of normal weight. One or more postoperative complications occurred in 35.4% of the patients following pancreatic resection. Among patients who were overweight or obese, 42.9% experienced one or more complications,significantly higher than normal weight(29.6%)individuals(P = 0.0086). Compared with individuals who had normal weight, those with a BMI ≥ 24.0kg/m2 had higher delayed gastric emptying(19.9% vs5.8%, P < 0.0001) and bile leak(7.7% vs 1.9%, P =0.0068). There were no significant differences seen in pancreatic fistula, gastrointestinal hemorrhage, reoperation,readmission, or other complications. BMI did not show a significant association with intraoperative blood loss, operative time, length of hospital stay, or cost.CONCLUSION: Higher BMI increases the risk for postoperative complications after pancreatectomy in the Chinese population. The findings require replication in future studies with larger sample sizes.展开更多
Terahertz time-domain spectroscopy(THz-TDS)is an effective nondestructive and noninvasive tool for investigating sulfur-containing pigments.Combined with Raman spectroscopy and vibrational mode analysis,it is signific...Terahertz time-domain spectroscopy(THz-TDS)is an effective nondestructive and noninvasive tool for investigating sulfur-containing pigments.Combined with Raman spectroscopy and vibrational mode analysis,it is significant for artifact identification and conservation.In this work,the terahertz absorption spectra of pararealgar(As_(4)S_(4))and orpiment(As_(2)S_(3))samples mixed with polytetrafluoroethylene(PTFE)are characterized in a range from 0.2 THz to 2.2 THz,and their distinctive peaks are observed,respectively.Meanwhile,qualitative analysis is also implemented by using Raman spectroscopy as a complementary technique.The lattice vibrations are simulated by using solid-state density functional theory(ss-DFT),illustrating different characteristic absorption peaks for specific crystalline structures and dynamic properties.This work provides a reliable database of sulfur-containing pigments for using the THz technology to actually analyze and diagnose cultural relics.展开更多
We investigate the electronic structures and phase stability of ZnO, CdO and the related alloys in rocksalt(B1)and wurzite(B4) crystal, using the first-principle density functional theory within the hybrid functio...We investigate the electronic structures and phase stability of ZnO, CdO and the related alloys in rocksalt(B1)and wurzite(B4) crystal, using the first-principle density functional theory within the hybrid functional approximation. By varying the concentration of Zn components from 0% to 100%, we find that the Zn_xCd(1-x)O alloy undergoes a phase transition from octahedron to tetrahedron at x = 0.32, in agreement with the recent experimental findings. The phase transition leads to a mutation of the electron mobility originated from the changes of the effective mass. Our results qualify Zn O/Cd O alloy as an attractive candidate for photo-electrochemical and solar cell power applications.展开更多
Various SARS-CoV-2-related coronaviruses have been increasingly identified in pangolins,showing a potential threat to humans.Here we report the infectivity and pathogenicity of the SARS-CoV-2-related virus,PCoV-GX/P2V...Various SARS-CoV-2-related coronaviruses have been increasingly identified in pangolins,showing a potential threat to humans.Here we report the infectivity and pathogenicity of the SARS-CoV-2-related virus,PCoV-GX/P2V,which was isolated from a Malayan pangolin(Manis javanica).PCoV-GX/P2V could grow in human hepatoma,colorectal adenocarcinoma cells,and human primary nasal epithelial cells.It replicated more efficiently in cells expressing human angiotensin-converting enzyme 2(hACE2)as SARS-CoV-2 did.After intranasal inoculation to the hACE2-transgenic mice,PCoV-GX/P2V not only replicated in nasal turbinate and lungs,but also caused interstitial pneumonia,characterized by infiltration of mixed inflammatory cells and multifocal alveolar hemorrhage.Existing population immunity established by SARS-CoV-2 infection and vaccination may not protect people from PCoV-GX/P2V infection.These findings further verify the hACE2 utility of PCoV-GX/P2V by in vivo experiments using authentic viruses and highlight the importance for intensive surveillance to prevent possible cross-species transmission.展开更多
To the Editor:In December 2019,coronavirus disease 2019 outbreak caused by the 2019 novel coronavirus(2019-nCoV)happened in Wuhan,China.Now,it has posed a worldwide public health threat.Real-time quanti-tative polymer...To the Editor:In December 2019,coronavirus disease 2019 outbreak caused by the 2019 novel coronavirus(2019-nCoV)happened in Wuhan,China.Now,it has posed a worldwide public health threat.Real-time quanti-tative polymerase chain reaction(RT-qPCR)was recom-mended as an effective pathogen detection method and has played an important role in prevention and control of the current outbreak.Many research institutions have released their primer sets for RT-qPCR.If the variant sites were located in the primer regions,the efficiency of RT-qPCR would be reduced,thus possibly causing false negative results,and leading to unpredictable impact on the diagnosis of patients and the control of this outbreak.Therefore,a comprehensive investigation on 2019-nCoV genome variation is necessary to evaluate the effectiveness of current released RT-qPCR methods.展开更多
基金funded and supported by the Youth Science and Technology Project of Henan Provincial Bureau of Geology and Mineral Resources,YDKQKC[2008]No.8.
文摘Over the years,the Shaying River Basin has experienced frequent instances of river pollution.The presence of numerous critical pollutant discharge enterprises and sewage-treatment plants in the vicinity of the Shaying River has transformed it a major tributary with relatively serious pollution challenge within the upper reaches of Huaihe River Basin.To study the sources of manganese(Mn),chromium(Cr),nickel(Ni),arsenic(As),cadmium(Cd)and lead(Pb)in Shaying River water,123 sets of surface water samples were collected from 41 sampling points across the entire basin during three distinct phases from 2019 to 2020,encompassing normal water period,dry season and wet season.The primary origins of heavy metals in river water were determined by analyzing the heavy metal contents in urban sewage wastewater,industrial sewage wastewater,groundwater,mine water,and the heavy metal contributions from agricultural non-point source pollution.The analytical findings reveal that Mn primarily originates from shallow groundwater used for agricultural irrigation,While Cr mainly is primarily sourced from urban sewage treatment plant effluents,coal washing wastewater,tannery wastewater,and industrial discharge related to metal processing and manufacturing.Ni is mainly contributed by urban sewage treatment plant effluents and industrial wastewater streams associated with machinery manufacturing and metal processing.Cd primarily linked to industrial wastewater,particularly from machinery manufacturing and metal processing facilities,while Pb is predominantly associated with urban sewage treatment plant effluents and wastewater generated in Pb processing and recycling wastewater.These research provides a crucial foundation for addressing the prevention and control of dissolved heavy metals at their sources in the Shaying River.
基金Supported by the National Natural Science Foundation of China,No.81970493 and No.82270590and the National Natural Science Foundation of Hunan Province,No.2021JJ30973 and No.2021JJ40844.
文摘BACKGROUND The case of Crohn's disease involving the duodenum is rare,and its surgical management requires a thorough understanding.AIM To investigate the surgical management of duodenal Crohn’s disease.METHODS We systematically reviewed patients diagnosed with duodenal Crohn's disease who underwent surgery in the Department of Geriatrics Surgery of the Second Xiangya Hospital of Central South University from January 1,2004,to August 31,2022.The general information,surgical procedures,prognosis,and other information of these patients were collected and summarized.RESULTS A total of 16 patients were diagnosed with duodenal Crohn’s disease,where 6 cases had primary duodenal Crohn’s disease,and 10 had secondary duodenal Crohn’s disease.Among patients with primary disease,5 underwent duodenal bypass and gastrojejunostomy,and 1 received pancreaticoduodenectomy.Among those with a secondary disease,6 underwent closure of duodenal defect and colectomy,3 received duodenal lesion exclusion and right hemicolectomy,and 1 underwent duodenal lesion exclusion and double-lumen ileostomy.CONCLUSION Crohn's disease involving the duodenum is a rare condition.Different surgical management should be applied for patients with Crohn's disease presenting with different clinical manifestations.
基金Supported by National Natural Science Foundation of China,No.81401947Beijing Nova Program,No.xxjh2015A090
文摘AIM To examine the impact of aging on the short-term outcomes following pancreatic resection(PR) in elderly patients.METHODS A retrospective cohort study using prospectively collected data was conducted at the China National Cancer Center. Consecutive patients who underwent PR from January 2004 to December 2015 were identifiedand included. ‘Elderly patient' was defined as ones age 65 and above. Comorbidities, clinicopathology, perioperative variables, and postoperative morbidity and mortality were compared between the elderly and young patients. Univariate and multivariate analyses were performed using the Cox proportional hazard model for severe postoperative complications(grades Ⅲb-Ⅴ).RESULTS A total of 454(63.4%) patients were < 65-yearsold and 273(36.6%) patients were ≥ 65-yearsold, respectively. Compared to patients < 65-yearsold, elderly patients had worse American Society of Anesthesiologists scores(P = 0.007) and more comorbidities(62.6% vs 32.4%, P < 0.001). Elderly patients had more severe postoperative complications(16.8% vs 9.0%, P = 0.002) and higher postoperative mortality rates(5.5% vs 0.9%, P < 0.001). In the multivariate Cox proportional hazards model for severe postoperative complications, age ≥ 65 years [hazard ratio(HR) = 1.63; 95% confidence interval(CI): 1.18-6.30], body mass index ≥ 24 kg/m^2(HR = 1.20, 95%CI: 1.07-5.89), pancreaticoduodenectomy(HR = 4.86, 95%CI: 1.20-8.31) and length of operation ≥ 241 min(HR = 2.97; 95%CI: 1.04-6.14) were significant(P = 0.010, P = 0.041, P = 0.017 and P = 0.012, respectively).CONCLUSION We found that aging is an independent risk factor for severe postoperative complications after PR. Our results might contribute to more informed decision-making for elderly patients.
基金Supported by National Natural Science Foundation of China,No.81401947Beijing Nova Program,No.xxjh2015A090Cancer Hospital of the Chinese Academy of Medical Sciences,No.LC2015L11
文摘AIM to evaluate the association of body mass index(b MI) with the overall survival of pancreatic ductal adenocarcinoma(PDAC) patients.METHODS A retrospective analysis of PDAC patients diagnosed in the National Cancer Center of China between January 1999 and December 2014 was performed. these patients were categorized into four b MI groups(< 18.5, 18.5-22.9, 23-27.4 and ≥ 27.5 kg/m2). χ2 tests for comparison of the proportions of categorical variables, and Student's t-test or Mann-Whitney test for continuous variables were employed. Survival analysis was performed with the Kaplan-Meyer method. their HRs of mortality and 95%CIs were estimated using the Cox proportional hazards model.RESULTS With a median age of 59.6 years(range: 22.5-84.6 years), in total 1783 PDAC patients were enrolled in this study. their mean usual b MI was 24.19 ± 3.53 for the whole cohort. More than half of the patients(59.3%) experienced weight loss during the disease onset and progression. Compared with healthy-weight individuals, newly diagnosed patients who were overweight or obese had more severe weight loss during their disease onset and progression(P < 0.001). Individuals who were overweight or obese were associated with positive smoking history(P < 0.001). A significant difference in comorbidity of diabetes(P = 0.044) and coronary artery disease(P < 0.001) was identified between high b MI and normal-weight patients. After a median follow-up of 8 mo, the survival analysis showed no association between b MI and the overall survival(P = 0.90, n = 1783). When we stratified the whole cohort by pancreatic cancer stage, no statistically significant association between b MI and overall survival was found for resectable(P = 0.99, n = 217), unresectable locally advanced(P = 0.90, n = 316) and metastatic patients(P = 0.88, n = 1250), respectively. the results did not change when we used the b MI at diagnosis.CONCLUSION Our results showed no significance of b MI for the overall survival of PDAC patients.
基金Supported by National Natural Science Foundation of China,No.81401947the Specialized Research Fund for the Doctoral Program of Higher Education,No.20131106120011The Cancer Hospital/Institute of the Chinese Academy of Medical Sciences,No.JK2011B13,Beijing Nova Program
文摘AIM: To examine the impact of body mass index(BMI)on outcomes following pancreatic resection in the Chinese population.METHODS: A retrospective cohort study using prospectively collected data was conducted at the Cancer Hospital of the Chinese Academy of Medical Sciences, China National Cancer Center. Individuals who underwent pancreatic resection between January2004 and December 2013 were identified and included in the study. Persons were classified as having a normal weight if their BMI was < 24 kg/m2 and overweight/obese if their BMI was ≥ 24 kg/m2 as defined by the International Life Sciences Institute Focal Point in China. A χ 2 test(for categorical variables) or a t test(for continuous variables) was used to examine the differences in patients' characteristics between normal weight and overweight/obese groups. Multiple logistic regression models were used to assess the associationsof postoperative complications, operative difficulty,length of hospital stay, and cost with BMI, adjusting for age, sex, and type of surgery procedures.RESULTS: A total of 362 consecutive patients with data available for BMI calculation underwent pancreatic resection for benign or malignant disease from January1, 2004 to December 31, 2013. Of the 362 patients,156 were overweight or obese and 206 were of normal weight. One or more postoperative complications occurred in 35.4% of the patients following pancreatic resection. Among patients who were overweight or obese, 42.9% experienced one or more complications,significantly higher than normal weight(29.6%)individuals(P = 0.0086). Compared with individuals who had normal weight, those with a BMI ≥ 24.0kg/m2 had higher delayed gastric emptying(19.9% vs5.8%, P < 0.0001) and bile leak(7.7% vs 1.9%, P =0.0068). There were no significant differences seen in pancreatic fistula, gastrointestinal hemorrhage, reoperation,readmission, or other complications. BMI did not show a significant association with intraoperative blood loss, operative time, length of hospital stay, or cost.CONCLUSION: Higher BMI increases the risk for postoperative complications after pancreatectomy in the Chinese population. The findings require replication in future studies with larger sample sizes.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61805129 and 11874245)the National Key Research and Development Program of China(Grant No.2021YFB3200100)the Yungang Special Fund of Shanxi Datong University,China(Grant No.2020YGZX005)。
文摘Terahertz time-domain spectroscopy(THz-TDS)is an effective nondestructive and noninvasive tool for investigating sulfur-containing pigments.Combined with Raman spectroscopy and vibrational mode analysis,it is significant for artifact identification and conservation.In this work,the terahertz absorption spectra of pararealgar(As_(4)S_(4))and orpiment(As_(2)S_(3))samples mixed with polytetrafluoroethylene(PTFE)are characterized in a range from 0.2 THz to 2.2 THz,and their distinctive peaks are observed,respectively.Meanwhile,qualitative analysis is also implemented by using Raman spectroscopy as a complementary technique.The lattice vibrations are simulated by using solid-state density functional theory(ss-DFT),illustrating different characteristic absorption peaks for specific crystalline structures and dynamic properties.This work provides a reliable database of sulfur-containing pigments for using the THz technology to actually analyze and diagnose cultural relics.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11474273 and 11634003the Youth Innovation Promotion Association of Chinese Academy of Sciences under Grant No 2017154
文摘We investigate the electronic structures and phase stability of ZnO, CdO and the related alloys in rocksalt(B1)and wurzite(B4) crystal, using the first-principle density functional theory within the hybrid functional approximation. By varying the concentration of Zn components from 0% to 100%, we find that the Zn_xCd(1-x)O alloy undergoes a phase transition from octahedron to tetrahedron at x = 0.32, in agreement with the recent experimental findings. The phase transition leads to a mutation of the electron mobility originated from the changes of the effective mass. Our results qualify Zn O/Cd O alloy as an attractive candidate for photo-electrochemical and solar cell power applications.
基金supported by the National Natural Science Foundation of China(81621005)。
文摘Various SARS-CoV-2-related coronaviruses have been increasingly identified in pangolins,showing a potential threat to humans.Here we report the infectivity and pathogenicity of the SARS-CoV-2-related virus,PCoV-GX/P2V,which was isolated from a Malayan pangolin(Manis javanica).PCoV-GX/P2V could grow in human hepatoma,colorectal adenocarcinoma cells,and human primary nasal epithelial cells.It replicated more efficiently in cells expressing human angiotensin-converting enzyme 2(hACE2)as SARS-CoV-2 did.After intranasal inoculation to the hACE2-transgenic mice,PCoV-GX/P2V not only replicated in nasal turbinate and lungs,but also caused interstitial pneumonia,characterized by infiltration of mixed inflammatory cells and multifocal alveolar hemorrhage.Existing population immunity established by SARS-CoV-2 infection and vaccination may not protect people from PCoV-GX/P2V infection.These findings further verify the hACE2 utility of PCoV-GX/P2V by in vivo experiments using authentic viruses and highlight the importance for intensive surveillance to prevent possible cross-species transmission.
基金This work was supported by the National Key Research&Development Program of China(No.2020YFC0840900)the Beijing Municipal Science and Technology Project(No.Z201100001020004).
文摘To the Editor:In December 2019,coronavirus disease 2019 outbreak caused by the 2019 novel coronavirus(2019-nCoV)happened in Wuhan,China.Now,it has posed a worldwide public health threat.Real-time quanti-tative polymerase chain reaction(RT-qPCR)was recom-mended as an effective pathogen detection method and has played an important role in prevention and control of the current outbreak.Many research institutions have released their primer sets for RT-qPCR.If the variant sites were located in the primer regions,the efficiency of RT-qPCR would be reduced,thus possibly causing false negative results,and leading to unpredictable impact on the diagnosis of patients and the control of this outbreak.Therefore,a comprehensive investigation on 2019-nCoV genome variation is necessary to evaluate the effectiveness of current released RT-qPCR methods.