Objective: To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection. Methods: The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELI...Objective: To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection. Methods: The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELISA and its comparison with viral RNA detection via real time PCR and Ig M antibodies detection by ELISA. Results: A total of 1 270 serum samples were tested 86%(1 097/1 270) were detected positive by one or more than one diagnostic test. Out of 1 270, 64%(807/1 270) were positive by NS1 ELISA and 52%(662/1 270), 51%(646/1 270) were positive by real-time RT-PCR and Ig M ELISA respectively.Conclusions: NS1 antigen detection ELISA is highly suitable diagnostic tools and it also has great value for use in outbreak and epidemic situation.展开更多
During the late incubation period or initial phase of dengue virus infection,laboratory confirmation is through viral isolation in cell culture and/or molecular investigations, or immunofluorescence,or immunohistochem...During the late incubation period or initial phase of dengue virus infection,laboratory confirmation is through viral isolation in cell culture and/or molecular investigations, or immunofluorescence,or immunohistochemistry[1].The dengue virus non-structural antigen NSl that would develop before the appearance of dengue IgM and/or IgG is emerging as a suitable option for dengue diagnosis[2].Platelet therapy is a standard clinical practice for dengue patients with severe thrombocytopenia[3].However,during introductory screening,platelet count is not being done in many cases. This results in delays of platelet therapy. In the course of the current(2010) spurt of dengue in New Delhi[4],simultaneous screening for NSl,IgM and IgG and platelet enumeration has been introduced at the展开更多
To obtain the NS1 gene of swine influenza virus H9N2 subtype expressed efficiently in E. coli, to develope the effective diagnostic methods for swine influenza virus H9N2 subtype, the NS 1 gene of swine influenza viru...To obtain the NS1 gene of swine influenza virus H9N2 subtype expressed efficiently in E. coli, to develope the effective diagnostic methods for swine influenza virus H9N2 subtype, the NS 1 gene of swine influenza virus H9N2 subtype was amplified by reverse transcriptase polymerase chain reaction （RT-PCR） and cloned into a prokaryotic expression vector, pET-28a（＋）, and overexpressed in E. coli BL21-DE3 after induction with 5 mmol L-1 lactose. The recombinant protein was purified by Ni-NTA and identified by western-blotting. An indirect enzyme-linked immunosorbent assay （ELISA） was used to analyze the antigenicity of the recombinant protein. The recombinant protein of NS1 was about 26 kD. The Western-blotting test showed that the recombinant protein reacted specifically with positive sera. The results of the ELISA test showed that the recombinant protein had good antigenicity.展开更多
Objective:To High light some epidemiological,clinical and diagnostic features of dengue fever during an outbreak and the role of different diagnostic techniques to achieve the highest level of accuracy in results.Meth...Objective:To High light some epidemiological,clinical and diagnostic features of dengue fever during an outbreak and the role of different diagnostic techniques to achieve the highest level of accuracy in results.Methods:Blood samples(n=323) were collected along with epidemiological and clinical data from suspected dengue patients who visited different hospitals in Swat and Mansehra district of Pakistan between May-November 2013 during a dengue outbreak.Samples were tested for the detection of viral nucleic acid by real-lime PCR.non structural protein-1(NS1antigen and IgM antibodies by ELISA.Results:Out of 323 cases with clinical dengue infection,304 were positive by one or more diagnostic parameter:201 samples were positive by real-time PCR,209 were positive by NS1 ELISA and 190 were positive by IgM antibodies.Sensitivities of real-time PCR and NS1 F.LISA were comparable for early diagnosis of dengue virus infection.IgM antibody detection assay was found useful for the diagnosis in the samples collected later than day 5 of onset.Conclusions:The use of real-lime PCR or detection of non stnictural protein NS 1 by ELISA followed by IgM antibodies detection can be recommended for early diagnosis of dengue virus infection with a high level of accuracy.展开更多
文摘Objective: To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection. Methods: The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELISA and its comparison with viral RNA detection via real time PCR and Ig M antibodies detection by ELISA. Results: A total of 1 270 serum samples were tested 86%(1 097/1 270) were detected positive by one or more than one diagnostic test. Out of 1 270, 64%(807/1 270) were positive by NS1 ELISA and 52%(662/1 270), 51%(646/1 270) were positive by real-time RT-PCR and Ig M ELISA respectively.Conclusions: NS1 antigen detection ELISA is highly suitable diagnostic tools and it also has great value for use in outbreak and epidemic situation.
文摘During the late incubation period or initial phase of dengue virus infection,laboratory confirmation is through viral isolation in cell culture and/or molecular investigations, or immunofluorescence,or immunohistochemistry[1].The dengue virus non-structural antigen NSl that would develop before the appearance of dengue IgM and/or IgG is emerging as a suitable option for dengue diagnosis[2].Platelet therapy is a standard clinical practice for dengue patients with severe thrombocytopenia[3].However,during introductory screening,platelet count is not being done in many cases. This results in delays of platelet therapy. In the course of the current(2010) spurt of dengue in New Delhi[4],simultaneous screening for NSl,IgM and IgG and platelet enumeration has been introduced at the
文摘To obtain the NS1 gene of swine influenza virus H9N2 subtype expressed efficiently in E. coli, to develope the effective diagnostic methods for swine influenza virus H9N2 subtype, the NS 1 gene of swine influenza virus H9N2 subtype was amplified by reverse transcriptase polymerase chain reaction （RT-PCR） and cloned into a prokaryotic expression vector, pET-28a（＋）, and overexpressed in E. coli BL21-DE3 after induction with 5 mmol L-1 lactose. The recombinant protein was purified by Ni-NTA and identified by western-blotting. An indirect enzyme-linked immunosorbent assay （ELISA） was used to analyze the antigenicity of the recombinant protein. The recombinant protein of NS1 was about 26 kD. The Western-blotting test showed that the recombinant protein reacted specifically with positive sera. The results of the ELISA test showed that the recombinant protein had good antigenicity.
文摘Objective:To High light some epidemiological,clinical and diagnostic features of dengue fever during an outbreak and the role of different diagnostic techniques to achieve the highest level of accuracy in results.Methods:Blood samples(n=323) were collected along with epidemiological and clinical data from suspected dengue patients who visited different hospitals in Swat and Mansehra district of Pakistan between May-November 2013 during a dengue outbreak.Samples were tested for the detection of viral nucleic acid by real-lime PCR.non structural protein-1(NS1antigen and IgM antibodies by ELISA.Results:Out of 323 cases with clinical dengue infection,304 were positive by one or more diagnostic parameter:201 samples were positive by real-time PCR,209 were positive by NS1 ELISA and 190 were positive by IgM antibodies.Sensitivities of real-time PCR and NS1 F.LISA were comparable for early diagnosis of dengue virus infection.IgM antibody detection assay was found useful for the diagnosis in the samples collected later than day 5 of onset.Conclusions:The use of real-lime PCR or detection of non stnictural protein NS 1 by ELISA followed by IgM antibodies detection can be recommended for early diagnosis of dengue virus infection with a high level of accuracy.
