Objective: Multidrug resistance(MDR) is one of the most important reasons for treatment failure and recurrence of acute leukemia. Its manifestations are different in children with acute lymphoblastic leukemia(ALL...Objective: Multidrug resistance(MDR) is one of the most important reasons for treatment failure and recurrence of acute leukemia. Its manifestations are different in children with acute lymphoblastic leukemia(ALL) which may be due to different detection methods. This study was to detect the expression of MDR1 mRNA in bone marrow cells of children with ALL by real-time fluorescence- quantitative reverse transcription polymerase-chain reaction(FQ-RT-PCR), and combine minimal residual desease(MRD) detection by flow cytometry(FCM) and to study their relationship with treatment response and prognosis of ALL. Methods:The MDR1 mRNA levels in bone marrow cells from 67 children with ALL[28 had newly diagnosed disease, 27 had achieved complete remission(CR), 12 recurrent] and 22 children without leukemia were detected by FQ-RT-PCR. MRD was detected by FCM. The patients were observed for 9-101 months, with a median of 64 months. Results:Standard curves of human MDR1 and GAPDH genes were constructed successfully. MDR1 mRNA was detected in all children with a positive rate of 100%. The mRNA level of MDR1 was similar among the newly diagnosed ALL group, CR group, and control group(P 〉 0.05), but significantly higher in the recurrence group than that in newly diagnosed disease group and control group(0.50 ± 0.55 vs. 0.09 ± 0.26 and 0.12 ± 0.23, P〈 0.05). 54 ALL patients were followed up, and it was found that MDR1 mRNA level was significantly higher in ALL patients within 3 years duration than that of ALL patients with 3-6 years and over 6 years duration(0.63 ± 0.56 vs. 0.11 ± 0.12 and 0.04 ± 0.06, P〈 0.01). For the 28 children with newly diagnosed disease, the MDR1 mRNA level was similar between WBC 〉 50 ~ 109 group and WBC〈50 × 10^9 group(P〉 0.05). In the 33 CR patients, the MDR1 mRNA level was significantly higher in MRD〉10a group than that in MRD〈10a group(0.39 ± 0.47 vs. 0.03 ± 0.03, P 〈 0.05). Conclusion:The sensitivity and specificity of FQ-RT-PCR in detecting MDR1 mRNA in bone marrowy cells of children with ALL patients are high. MDR1 mRNA is expressed in children with and without leukemia. MDR1 mRNA is highly expressed in the CR ALL patients with high MRD, recurrence and short duration(within 3 years). Monitoring MRD and the MDR1 mRNA level might be helpful for individual treatment.展开更多
[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel rea...[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel real-time fluorescence quantitative RT-PCR assay was established and optimized for simultaneously detecting DNA/RNA of four shrimp viruses (WSSV, IHHNV, TSV and YHV ). [ Result] The optimized real-time fluorescence quantitative RT-PCR system gener- ated typical amplification curves with high amplification efficiencies (E = 1.06, 1.07, 0.92 and 0.92, respectively), good hnear relationship ( r = 1 ), uniform repeatability ( standard deviation = 0.05 - 0.46 ; variation coefficient = 0.26% - 1.62% ) and high sensitivity, exhibiting no significant differences compared with re- al-time fluorescence quantitative PCR (average error of Ct value = 0.04 -0.40; T = 0.53 -2.50; P 〉 0.05 ). The total detection time was about 1 h. [ Conclusion] The optimized real-time fluorescence quantitative RT-PCR system can be used for rapid detection of WSSV, IHHNV, TSV and YHV.展开更多
Burkholderia glumae causing seedling rot and grain rot of rice was listed as a plant quarantine disease of China in 2007. It's quite necessary to set up effective detection methods for the pathogen to manage further ...Burkholderia glumae causing seedling rot and grain rot of rice was listed as a plant quarantine disease of China in 2007. It's quite necessary to set up effective detection methods for the pathogen to manage further dispersal of this disease. The present study combined the real-time PCR method with classical PCR to increase the detecting efficiency, and to develop an accurate, rapid and sensitive method to detect the pathogen in the seed quarantine for effective management of the disease. The results showed that all the tested strains of B. glumae produced about 139 bp specific fragments by the real-time PCR and the general PCR methods, while others showed negative PCR result. The bacteria could be detected at the concentrations of 1×10^4 CFU/mL by general PCR method and at the concentrations below 100 CFU/mL by real-time fluorescence PCR method. B. glumae could be detected when the inoculated and healthy seeds were mixed with a proportion of 1:100.展开更多
Summary:The novel coronavirus SARS-CoV-2 caused an outbreak of pneumonia in Wuhan,Hubei province of China in January 2020.This study aims to investigate the effects of different temperature and time durations of virus...Summary:The novel coronavirus SARS-CoV-2 caused an outbreak of pneumonia in Wuhan,Hubei province of China in January 2020.This study aims to investigate the effects of different temperature and time durations of virus inactivation on the results of PCR testing for SARS-CoV-2.Twelve patients at the Renmin Hospital of Wuhan University suspected of being infected with SARS-CoV-2 were selected on February 13,2020 and throat swabs were taken.The swabs were stored at room tempcrature(20-25℃),then divided into aliquots and subjected to different temperature for different periods in order to inactivate the viruses(56℃for 30,45,60 min;65,70,80℃for 10,15,20 min).Control aliquots were stored at room temperature for 60 min.Then all aliquots were tested in a real-time fluorescence PCR using primers against SARS-CoV-2.Regardless of inactivation temperature and time,7 of 12 cases(58.3%)tested were positive for SARS-CoV-2 by PCR,and cycle threshold values were similar.These results suggest that virus inactivation parameters exert minimal infuence on PCR test results.Inactivation at 65℃for 10 min may be sufficient to ensure safe,reliable testing.展开更多
This study was to develop the real-time fluorescence quantitative PCR technique for detecting the ratoon stunting disease (RSD) in virus-free seedcane seedlings. Healthy tissue culture seedlings were obtained from s...This study was to develop the real-time fluorescence quantitative PCR technique for detecting the ratoon stunting disease (RSD) in virus-free seedcane seedlings. Healthy tissue culture seedlings were obtained from six plants of sugarcane ROC22, which had been confirmed RSD-positive by detecting the sugarcane juice, by employing the sugarcane seedlings production protocol. Real-time fluorescence quantitative PCR was used to detect RSD pathogens in tissue culture sam- pies. The results showed that target fragment of RSD pathogens was not found in all 10 samples in real-time fluorescence quantitative PCR, with the Ct values of 37 - 39. The healthy tissue culture sugarcane seedlings do not carry RSD pathogens, indicating that adopting healthy seedcane seedlings production technique could thoroughly get rid of RSD pathogens.展开更多
Porcine epidemic diarrhea,a highly contagious enteric infectious disease caused by the porcine epidemic diarrhea virus( PEDV) with symptoms of vomit,diarrhea,loss of appetite of suckling pig,has led to serious econo...Porcine epidemic diarrhea,a highly contagious enteric infectious disease caused by the porcine epidemic diarrhea virus( PEDV) with symptoms of vomit,diarrhea,loss of appetite of suckling pig,has led to serious economic loss to the global swine industry. In this study,a real-time fluorescence reverse transcription loop-mediated isothermal amplification( RT-LAMP) assay was developed to detect PEDV RNA. The real-time fluorescence RT-LAMP assay was performed at62 ℃ for 60 min,using a simple and portable device,the ESE-Quant Tube Scanner. The detection limit of RNA was 2. 9 × 10~6 copies/μl,10 times as sensitive as RT-PCR,and the detection was specific only to PEDV. Application of this method to clinical samples yielded a positivity rate of 93%,which was higher than that of RT-PCR. This technique saves time and is efficient,and is thus expected to be useful for the diagnosis of PEDV infection in the field.展开更多
According to VP2 gene sequence of the porcine parvovirus virus strain NADL-2 (NC001718) available in GenBank (NC_001718), a pair of specific primer was designed, and the target fragment of 431 bp was obtained by P...According to VP2 gene sequence of the porcine parvovirus virus strain NADL-2 (NC001718) available in GenBank (NC_001718), a pair of specific primer was designed, and the target fragment of 431 bp was obtained by PCR amplification. The products were ligated with pMD18- T vector and then transformed into bacteria DH5α for recombinant plasmid extraction. After PCR identification and sequencing, recombinant plasmid was used as a standard template to establish the standard curve of SYBR Green I fluorescence quantitative PCR. Sensitivity test, specificity test and repeatability test were also determined. The results indicated that there was a good linear relationship between threshold cycle of the standard curve and template concentration, R2 =0.997 6. Tm ranged from 82.3 to 82.9 ℃, while the sensitivity was 72.1 copies/μl with good specificity and repeatability. The developed SYBR Green I real-time quantitative PCR method to detect PPV VP2 gene laid the basis for further studies on patho- oenesis, early clinical diaonosis of this virus and quantitative analysis of PPV infection.展开更多
Objective Establishing a highly sensitive real-time fluorescence quantitative PCR (qPCR) method for universal testing of epidemic African swine fever virus (ASFV) strains. Methods The ASFV p72 gene was targeted to des...Objective Establishing a highly sensitive real-time fluorescence quantitative PCR (qPCR) method for universal testing of epidemic African swine fever virus (ASFV) strains. Methods The ASFV p72 gene was targeted to design primer probes covering 24 p72 genotypes. The optimal amount of dimethylsulphoxide (DMSO) for qPCR amplification was determined, Various sensitivity and limit of detection (LOD) tests were performed, and clinical samples from China and imported goods were tested. Results The optimal primer-probe combination could specifically detect ASFV, 1.5% DMSO was optimal for qPCR, and LOD reached 3.2 copies/μL with good reproducibility (n = 20, p = 0.369). The method was employed to test 142 clinically suspected samples, of which 30 pig blood and 37 pig tissue samples were ASFV-positive. Moreover, the positive testing rate for ASFV was higher than for the standard qPCR method recommended by the Office International Des Epizooties (OIE), and for the commercially available kit. Thus, our method is superior for testing weakly positive samples with low virus titre, and epidemic strains present in imported goods. Conclusion Our method could be employed for universal testing of epidemic ASFV strains worldwide, ensuring wider coverage of hosts and ASFV strains/endemic strains, reducing false<span style="font-family:;" "=""> </span><span style="font-family:Verdana;">negatives, and benefitting early diagnosis.</span>展开更多
猴逆转录病毒(Simian type D retrovirus,SRV)是引起猴获得性免疫缺陷综合征(Simian acquired immunodeficiency syndrome,SAIDS)的病原之一,其严重危害猴的健康,并威胁与猴接触人员的健康,是无特定病原体(SPF)猴必须排除的病毒之一。...猴逆转录病毒(Simian type D retrovirus,SRV)是引起猴获得性免疫缺陷综合征(Simian acquired immunodeficiency syndrome,SAIDS)的病原之一,其严重危害猴的健康,并威胁与猴接触人员的健康,是无特定病原体(SPF)猴必须排除的病毒之一。为了应对口岸对进出境野生及实验用灵长类动物SRV感染情况的监测和流行病学调查的需要,建立了RT-PCR和real-time RT-PCR检测SRV的方法,并对方法的特异性、敏感性和稳定性进行了验证。展开更多
Erythropoietin-producing hepatocellular receptor and its membrane-bound ligands (Eph-Ephrin) system could regulate some mammalian blastocyst attachment and spreading. In order to investigate the involvement of the E...Erythropoietin-producing hepatocellular receptor and its membrane-bound ligands (Eph-Ephrin) system could regulate some mammalian blastocyst attachment and spreading. In order to investigate the involvement of the Eph-Ephrin system in swine embryo attachment, mRNA expression of Eph-Ephrin molecules in endometrium was examined by real-time RT- PCR during embryo implantation in pigs. The results indicated that mRNA expressions of Eph A5, A7 and Ephrin A5 all continually increased from pregnancy day 13 to 24. Ephrin A3 mRNA expression significantly increased from day 13 to 18 and decreased from day 18 to 24, and the expression was the lowest on pregnancy day l 3 and the highest on day 18. However, Ephrin A4 mRNA expression was the lowest on pregnancy day 18 and the highest on day 24, and the expression decreased from day 13 to 18 and increased from day 18 to 24. Furthermore, mRNA expressions of Eph A5 and A7 were both found in other tissues, such as brain, muscle, intestine, stomach, etc. These findings suggest that the Eph-Ephrin system may play an important role in regulating the contact between blastocysts and endometrium during swine embryo implantation.展开更多
Objective To detect Japanese encephalitis virus(JEV) rapidly and distinguish its genotypes, a TaqMan-based reverse transcriptase quantitative polymerase chain reaction(RT-PCR) detection system was developed.Method...Objective To detect Japanese encephalitis virus(JEV) rapidly and distinguish its genotypes, a TaqMan-based reverse transcriptase quantitative polymerase chain reaction(RT-PCR) detection system was developed.Methods By aligning the full-length sequences of JEV(G1-G5), six sets of highly specific TaqMan real-time RT-PCR primers and probes were designed based on the highly conserved NS1, NS2, and M genes of JEV, which included one set for non-specific JEV detection and five sets for the detection of specific JEV genotypes. Twenty batches of mosquito samples were used to evaluate our quantitative PCR assay.Results With the specific assay, no other flavivirus were detected. The lower limits of detection of the system were 1 pfu/mL for JEV titers and 100 RNA copies/μL. The coefficients of variation of this real-time RT-PCR were all 〈 2.8%. The amplification efficiency of this method was between 90% and 103%.Conclusion A TaqMan real-time RT-PCR detection system was successfully established to detect and differentiate all five JEV genotypes.展开更多
基金This work was supported by Science Project from Science and Tech- nology Department of HuBei province(2006AA301B56-3)
文摘Objective: Multidrug resistance(MDR) is one of the most important reasons for treatment failure and recurrence of acute leukemia. Its manifestations are different in children with acute lymphoblastic leukemia(ALL) which may be due to different detection methods. This study was to detect the expression of MDR1 mRNA in bone marrow cells of children with ALL by real-time fluorescence- quantitative reverse transcription polymerase-chain reaction(FQ-RT-PCR), and combine minimal residual desease(MRD) detection by flow cytometry(FCM) and to study their relationship with treatment response and prognosis of ALL. Methods:The MDR1 mRNA levels in bone marrow cells from 67 children with ALL[28 had newly diagnosed disease, 27 had achieved complete remission(CR), 12 recurrent] and 22 children without leukemia were detected by FQ-RT-PCR. MRD was detected by FCM. The patients were observed for 9-101 months, with a median of 64 months. Results:Standard curves of human MDR1 and GAPDH genes were constructed successfully. MDR1 mRNA was detected in all children with a positive rate of 100%. The mRNA level of MDR1 was similar among the newly diagnosed ALL group, CR group, and control group(P 〉 0.05), but significantly higher in the recurrence group than that in newly diagnosed disease group and control group(0.50 ± 0.55 vs. 0.09 ± 0.26 and 0.12 ± 0.23, P〈 0.05). 54 ALL patients were followed up, and it was found that MDR1 mRNA level was significantly higher in ALL patients within 3 years duration than that of ALL patients with 3-6 years and over 6 years duration(0.63 ± 0.56 vs. 0.11 ± 0.12 and 0.04 ± 0.06, P〈 0.01). For the 28 children with newly diagnosed disease, the MDR1 mRNA level was similar between WBC 〉 50 ~ 109 group and WBC〈50 × 10^9 group(P〉 0.05). In the 33 CR patients, the MDR1 mRNA level was significantly higher in MRD〉10a group than that in MRD〈10a group(0.39 ± 0.47 vs. 0.03 ± 0.03, P 〈 0.05). Conclusion:The sensitivity and specificity of FQ-RT-PCR in detecting MDR1 mRNA in bone marrowy cells of children with ALL patients are high. MDR1 mRNA is expressed in children with and without leukemia. MDR1 mRNA is highly expressed in the CR ALL patients with high MRD, recurrence and short duration(within 3 years). Monitoring MRD and the MDR1 mRNA level might be helpful for individual treatment.
文摘[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel real-time fluorescence quantitative RT-PCR assay was established and optimized for simultaneously detecting DNA/RNA of four shrimp viruses (WSSV, IHHNV, TSV and YHV ). [ Result] The optimized real-time fluorescence quantitative RT-PCR system gener- ated typical amplification curves with high amplification efficiencies (E = 1.06, 1.07, 0.92 and 0.92, respectively), good hnear relationship ( r = 1 ), uniform repeatability ( standard deviation = 0.05 - 0.46 ; variation coefficient = 0.26% - 1.62% ) and high sensitivity, exhibiting no significant differences compared with re- al-time fluorescence quantitative PCR (average error of Ct value = 0.04 -0.40; T = 0.53 -2.50; P 〉 0.05 ). The total detection time was about 1 h. [ Conclusion] The optimized real-time fluorescence quantitative RT-PCR system can be used for rapid detection of WSSV, IHHNV, TSV and YHV.
基金supported by National Natural Science Foundation of China(Grant No.30671397 and No.30871655)the Public Beneficial Research Project of Agricultural Ministry,China(Grant No.nyhyzx07-056)
文摘Burkholderia glumae causing seedling rot and grain rot of rice was listed as a plant quarantine disease of China in 2007. It's quite necessary to set up effective detection methods for the pathogen to manage further dispersal of this disease. The present study combined the real-time PCR method with classical PCR to increase the detecting efficiency, and to develop an accurate, rapid and sensitive method to detect the pathogen in the seed quarantine for effective management of the disease. The results showed that all the tested strains of B. glumae produced about 139 bp specific fragments by the real-time PCR and the general PCR methods, while others showed negative PCR result. The bacteria could be detected at the concentrations of 1×10^4 CFU/mL by general PCR method and at the concentrations below 100 CFU/mL by real-time fluorescence PCR method. B. glumae could be detected when the inoculated and healthy seeds were mixed with a proportion of 1:100.
基金This work was supported by grants from the Special Science and Technology Cooperation Project of Ningxia Hui Autonomous Region Key R&D Program(No.2018BFG02008)the National Science and Technology Key Projects on"Major Infectious Diseases such as HIV/AIDS,Viral Hepatitis Prevention and Treatment"(No.2017ZX10103005).
文摘Summary:The novel coronavirus SARS-CoV-2 caused an outbreak of pneumonia in Wuhan,Hubei province of China in January 2020.This study aims to investigate the effects of different temperature and time durations of virus inactivation on the results of PCR testing for SARS-CoV-2.Twelve patients at the Renmin Hospital of Wuhan University suspected of being infected with SARS-CoV-2 were selected on February 13,2020 and throat swabs were taken.The swabs were stored at room tempcrature(20-25℃),then divided into aliquots and subjected to different temperature for different periods in order to inactivate the viruses(56℃for 30,45,60 min;65,70,80℃for 10,15,20 min).Control aliquots were stored at room temperature for 60 min.Then all aliquots were tested in a real-time fluorescence PCR using primers against SARS-CoV-2.Regardless of inactivation temperature and time,7 of 12 cases(58.3%)tested were positive for SARS-CoV-2 by PCR,and cycle threshold values were similar.These results suggest that virus inactivation parameters exert minimal infuence on PCR test results.Inactivation at 65℃for 10 min may be sufficient to ensure safe,reliable testing.
基金Supported by Special Funds for Basic Scientific Research of Guangxi Sugarcane Research Institute(G2009006,G2010006,G2009015)Sci-tech Research and Development Program of Guangxi Academy of Agricultural Sciences(200805)
文摘This study was to develop the real-time fluorescence quantitative PCR technique for detecting the ratoon stunting disease (RSD) in virus-free seedcane seedlings. Healthy tissue culture seedlings were obtained from six plants of sugarcane ROC22, which had been confirmed RSD-positive by detecting the sugarcane juice, by employing the sugarcane seedlings production protocol. Real-time fluorescence quantitative PCR was used to detect RSD pathogens in tissue culture sam- pies. The results showed that target fragment of RSD pathogens was not found in all 10 samples in real-time fluorescence quantitative PCR, with the Ct values of 37 - 39. The healthy tissue culture sugarcane seedlings do not carry RSD pathogens, indicating that adopting healthy seedcane seedlings production technique could thoroughly get rid of RSD pathogens.
基金Supported by Science and Technology Research Project of Universities in Hebei Province,China(QN2014220)
文摘Porcine epidemic diarrhea,a highly contagious enteric infectious disease caused by the porcine epidemic diarrhea virus( PEDV) with symptoms of vomit,diarrhea,loss of appetite of suckling pig,has led to serious economic loss to the global swine industry. In this study,a real-time fluorescence reverse transcription loop-mediated isothermal amplification( RT-LAMP) assay was developed to detect PEDV RNA. The real-time fluorescence RT-LAMP assay was performed at62 ℃ for 60 min,using a simple and portable device,the ESE-Quant Tube Scanner. The detection limit of RNA was 2. 9 × 10~6 copies/μl,10 times as sensitive as RT-PCR,and the detection was specific only to PEDV. Application of this method to clinical samples yielded a positivity rate of 93%,which was higher than that of RT-PCR. This technique saves time and is efficient,and is thus expected to be useful for the diagnosis of PEDV infection in the field.
文摘According to VP2 gene sequence of the porcine parvovirus virus strain NADL-2 (NC001718) available in GenBank (NC_001718), a pair of specific primer was designed, and the target fragment of 431 bp was obtained by PCR amplification. The products were ligated with pMD18- T vector and then transformed into bacteria DH5α for recombinant plasmid extraction. After PCR identification and sequencing, recombinant plasmid was used as a standard template to establish the standard curve of SYBR Green I fluorescence quantitative PCR. Sensitivity test, specificity test and repeatability test were also determined. The results indicated that there was a good linear relationship between threshold cycle of the standard curve and template concentration, R2 =0.997 6. Tm ranged from 82.3 to 82.9 ℃, while the sensitivity was 72.1 copies/μl with good specificity and repeatability. The developed SYBR Green I real-time quantitative PCR method to detect PPV VP2 gene laid the basis for further studies on patho- oenesis, early clinical diaonosis of this virus and quantitative analysis of PPV infection.
文摘Objective Establishing a highly sensitive real-time fluorescence quantitative PCR (qPCR) method for universal testing of epidemic African swine fever virus (ASFV) strains. Methods The ASFV p72 gene was targeted to design primer probes covering 24 p72 genotypes. The optimal amount of dimethylsulphoxide (DMSO) for qPCR amplification was determined, Various sensitivity and limit of detection (LOD) tests were performed, and clinical samples from China and imported goods were tested. Results The optimal primer-probe combination could specifically detect ASFV, 1.5% DMSO was optimal for qPCR, and LOD reached 3.2 copies/μL with good reproducibility (n = 20, p = 0.369). The method was employed to test 142 clinically suspected samples, of which 30 pig blood and 37 pig tissue samples were ASFV-positive. Moreover, the positive testing rate for ASFV was higher than for the standard qPCR method recommended by the Office International Des Epizooties (OIE), and for the commercially available kit. Thus, our method is superior for testing weakly positive samples with low virus titre, and epidemic strains present in imported goods. Conclusion Our method could be employed for universal testing of epidemic ASFV strains worldwide, ensuring wider coverage of hosts and ASFV strains/endemic strains, reducing false<span style="font-family:;" "=""> </span><span style="font-family:Verdana;">negatives, and benefitting early diagnosis.</span>
文摘猴逆转录病毒(Simian type D retrovirus,SRV)是引起猴获得性免疫缺陷综合征(Simian acquired immunodeficiency syndrome,SAIDS)的病原之一,其严重危害猴的健康,并威胁与猴接触人员的健康,是无特定病原体(SPF)猴必须排除的病毒之一。为了应对口岸对进出境野生及实验用灵长类动物SRV感染情况的监测和流行病学调查的需要,建立了RT-PCR和real-time RT-PCR检测SRV的方法,并对方法的特异性、敏感性和稳定性进行了验证。
基金supported by the National Natural Science Foundation of China (30771540)the National High-Technology Research Development Program of China (2007AA10Z166)
文摘Erythropoietin-producing hepatocellular receptor and its membrane-bound ligands (Eph-Ephrin) system could regulate some mammalian blastocyst attachment and spreading. In order to investigate the involvement of the Eph-Ephrin system in swine embryo attachment, mRNA expression of Eph-Ephrin molecules in endometrium was examined by real-time RT- PCR during embryo implantation in pigs. The results indicated that mRNA expressions of Eph A5, A7 and Ephrin A5 all continually increased from pregnancy day 13 to 24. Ephrin A3 mRNA expression significantly increased from day 13 to 18 and decreased from day 18 to 24, and the expression was the lowest on pregnancy day l 3 and the highest on day 18. However, Ephrin A4 mRNA expression was the lowest on pregnancy day 18 and the highest on day 24, and the expression decreased from day 13 to 18 and increased from day 18 to 24. Furthermore, mRNA expressions of Eph A5 and A7 were both found in other tissues, such as brain, muscle, intestine, stomach, etc. These findings suggest that the Eph-Ephrin system may play an important role in regulating the contact between blastocysts and endometrium during swine embryo implantation.
基金supported by grants from the National Key Research and Development Program[2016YFD0500401]Development Grant of State Key Laboratory of Infectious Disease Prevention and Control[2015SKLID505,2014SKLID03]
文摘Objective To detect Japanese encephalitis virus(JEV) rapidly and distinguish its genotypes, a TaqMan-based reverse transcriptase quantitative polymerase chain reaction(RT-PCR) detection system was developed.Methods By aligning the full-length sequences of JEV(G1-G5), six sets of highly specific TaqMan real-time RT-PCR primers and probes were designed based on the highly conserved NS1, NS2, and M genes of JEV, which included one set for non-specific JEV detection and five sets for the detection of specific JEV genotypes. Twenty batches of mosquito samples were used to evaluate our quantitative PCR assay.Results With the specific assay, no other flavivirus were detected. The lower limits of detection of the system were 1 pfu/mL for JEV titers and 100 RNA copies/μL. The coefficients of variation of this real-time RT-PCR were all 〈 2.8%. The amplification efficiency of this method was between 90% and 103%.Conclusion A TaqMan real-time RT-PCR detection system was successfully established to detect and differentiate all five JEV genotypes.