Objective:To evaluate the diagnostic potential of cerebrospmal fluid (CSF) levels of β-amyloid protein (Aβ) as biochemical marker for senile dementia in clinical practice. Methods : Sensitive enzyme-linked immunosor...Objective:To evaluate the diagnostic potential of cerebrospmal fluid (CSF) levels of β-amyloid protein (Aβ) as biochemical marker for senile dementia in clinical practice. Methods : Sensitive enzyme-linked immunosorbent assay (ELISA) was performed in our lalxrratory to delect the CSF levels of Aβt-40, Aβ1-42 in 54 patients with Alzlteimer's disease (AD), and 30 normal controls (NC). Results: The cut off value of Aβ ratio and Aβ1-42 concentration in NC group provided 54. 51%, 90. 00% sensitivity and 81. 25%, 84. 38% specificity respectively in diagnosis of AD. Conclusion : AD group had a significant decreased level of Aβ1-42 and an increased level of Aβ ratio, compared with NC group.展开更多
Porcine reproductive and respiratory syndrome is caused by the PRRS virus (PRRSV),which has six structural proteins (GP2,GP3,GP4,GP5,M and N). GP5 and N protein are important targets for serological detection by enzym...Porcine reproductive and respiratory syndrome is caused by the PRRS virus (PRRSV),which has six structural proteins (GP2,GP3,GP4,GP5,M and N). GP5 and N protein are important targets for serological detection by enzyme-linked immunosorbent assay (ELISA) and other methods. Toward this goal,we developed an indirect ELISA with recombinant GP5 antigens and this method was validated by comparison to the LSI PRRSV-Ab ELISA kit. The results indicated that the optimal concentration of coated recombinant antigen was 0.2 μg/well for a serum dilution of 1:40. The rate of agreement with the LSI PRRSV-Ab kit was 88.7% (266/300). These results support the potential use of recombinant GP5 as an antigen for indirect ELISA to detect PRRSV antibodies in pigs.展开更多
Objective To detect the change of nerve growth factor (NGF) level in human amniotic fluid during gestation, and to explore the relationship between this change and fetal ventriculo-megaly (VM). Methods The studied sub...Objective To detect the change of nerve growth factor (NGF) level in human amniotic fluid during gestation, and to explore the relationship between this change and fetal ventriculo-megaly (VM). Methods The studied subjects (collected from 2004 to 2007) were divided into four groups, including the second-trimester pregnancy group (n=113), third-trimester pregnancy group (n=110), fetal cerebral VM group (n=12), and healthy control group (n=12) which matched with the VM group in gestational weeks. The amniotic fluid specimens were obtained during amniocentesis or cesarean section. The NGF levels in amniotic fluid were detected with en-zyme-linked immunosorbent assay. Results A significantly negative correlation was found between gestational age and the NGF level in amniotic fluid (r= 0.6149, P<0.0001). The NGF level in patients with fetal VM was significantly lower than that in healthy controls (33.95±29.24 pg/mL vs. 64.73±16.21 pg/mL, P=0.024). Conclusion NGF levels in amniotic fluid may be a sensitive marker for fetal VM.展开更多
Grass carp plays an important role in small-scale aquaculture in Vietnam. However, a severe disease, known in Vietnam as "Red Spot Disease", is causing significant economic loss in grass carp aquaculture. In...Grass carp plays an important role in small-scale aquaculture in Vietnam. However, a severe disease, known in Vietnam as "Red Spot Disease", is causing significant economic loss in grass carp aquaculture. In this study, the tissue samples isolated from the grass carp with Red Spot Disease in Vietnam are investigated and comparied with the control GCHV isolated in China by experimental infection, culture cell infection, serological cross reactivity, and RT-PCR amplification. Infected grass carp exhibits hemorrhage symptoms about 5 days after experimental injection with GCHV-V (Vietnam) strain. The symptoms and lethality induced by the GCHV-V strain are identical to that induced by the Chinese GCHV-9014 strain. The Chinese GCHV-873 strain induces typical cytopathogenic effects in 4 cell lines, such as CIK, CAB, FHM and GCO, from the 6 fish cell lines examined. No cytopathogenic effects are observed in all the 6 examined cell lines, including CAB, FHM, CIK, EPC, CCO and GCO, infected by the GCHV-V strain and GCHV-9014 strain. Immunodiffusion assays demonstrate an obvious cross-reactivity among three GCHV strains. Precipitin lines are clearly observed not only between the anti-GCHV-873 serum and the two strains GCHV-873 and GCHV-9014, but also between the anti-GCHV-873 serum and the GCHV-V strain. GCHV can be detected by immunodiffusion assays after three generations of blind propagations in the cell lines inoculated by GCHV-V strain. This implicates that GCHV-V viruses have been replicated and amplified despite there being no cytopathogenic effects observed in these examined cell lines. Three genome segments of GCHV, including S8, S9 and S10, are amplified by three sets of PCR primers designed according to the segment sequences published recently. The Q8fp and Q8rp primer set specific for genome segment S8 amplifies a 955 bp fragment from the extracted sample of diseased fish with Red Spot Disease, and the fragment size is identical to that amplified by the same primer set from control GCHV-873 strain. Simultaneously, the Q9fp and Q9rp primer set specific for genome segment S9 generates a same 635 bp product, and the Q10fp and Q10rp primer set specific for genome segment S10 produces a same 697 bp fragment from both template samples of diseased fish with Red Spot Disease and control GCHV-873 strain. The RT-PCR amplification and corresponding size comparison data indicate that the three GCHV-V genome segments extracted from the diseased grass carp with Red Spot Disease in Vietnam should be identical to that in control GCHV-873 strain from China. The data confirm that the causative agent of grass carp Red Spot Disease in Vietnam is a virus, and the virus is closely similar to GCHV strain in China.展开更多
AIM： To detect and evaluate the antibodies against Helicobacter pylori （H pylori） neutrophil-activating protein （HP-NAP） in patients with gastric cancer and other gastroduodenal diseases.METHODS： Recombinant HP-...AIM： To detect and evaluate the antibodies against Helicobacter pylori （H pylori） neutrophil-activating protein （HP-NAP） in patients with gastric cancer and other gastroduodenal diseases.METHODS： Recombinant HP-NAP was prepared from a prokaryotic expression system in Escherichia coll. Serum positivity and level of HP-NAP-specific antibodies in sera from 43 patients with gastric cancer, 28 with chronic gastritis, 28 with peptic ulcer, and 89 healthy controls were measured by rHP-NAP-based ELISA. rHP-NAP-stimulated production of interleukin-8 （IL-8） and growth-related oncogene （GROα） cytokines in the culture supernatant of SGC7901 gastric epithelial cells was also detected.RESULTS： The serum positivity and mean absorbancevalue of HP-NAP-specific antibodies in the gastriccancer group （97.7% and 1.01 ± 0.24） were significantly higher than those in the chronic gastritisgroup （85.7% and 0.89 ± 0.14, P 〈 0.005） and healthy control group （27.7% and 0.65 ± 0.18, P 〈 0.001）. The sensitivity and specificity of ELISA for the detection of HP-NAP-specific antibodies were 95.5% and 91.5%, respectively. HP-NAP could slightly upregulate IL-8 production in gastric epithelial cell lines but had no effect on GROα production.CONCLUSION： Infection with virulent H py/ori strains secreting HP-NAP is associated with severe gastroduodenal diseases, and HP-NAP may play a role in the development of gastric carcinoma, rHP-NAP- based ELISA can be used as a new method to detect H pylori infection. The direct effect of HP-NAP on gastric epithelial cells may be limited, but HP-NAP may contribute to inflammatory response or carcinogenesis by activating neutrophils.展开更多
Malachite green(MG), a dye, is an antifungal agent that has been used to treat and prevent fish diseases. It is metabolized into reduced leucomalachite green forms(LMG) that may reside in fish muscles for a long perio...Malachite green(MG), a dye, is an antifungal agent that has been used to treat and prevent fish diseases. It is metabolized into reduced leucomalachite green forms(LMG) that may reside in fish muscles for a long period, thus being harmful to human health. The aim of this study was to develop a competitive and direct enzyme-linked immunosorbent assay(ELISA) to detect MG and LMG specifically. The monoclonal antibody(m Ab) to LMG was generated using a hybridoma technique. The obtained m Ab showed good cross-reactivity(CR) to malachite green(MG), but not to crystal violet(CV) and Brilliant Green(BG). The m Ab was used to develop a fast detecting ELISA of MG and LMG in fish. By introducing the conjugation LMG-HRP, the detection capability was 0.37 ng m L-1 for MG and LMG. The mean recovery from spiked grass carp tissues ranged from 76.2% to 82.9% and the coefficients of variation varied between 1.8% and 7.5%. The stable and efficient monoclonal cell line obtained is a sustainable source of sensitive and specific antibody to MG and LMG.展开更多
基金Supported by Grant from National Ministry of Personnel Foundation for Distinguished Young Schotars of China(1998)
文摘Objective:To evaluate the diagnostic potential of cerebrospmal fluid (CSF) levels of β-amyloid protein (Aβ) as biochemical marker for senile dementia in clinical practice. Methods : Sensitive enzyme-linked immunosorbent assay (ELISA) was performed in our lalxrratory to delect the CSF levels of Aβt-40, Aβ1-42 in 54 patients with Alzlteimer's disease (AD), and 30 normal controls (NC). Results: The cut off value of Aβ ratio and Aβ1-42 concentration in NC group provided 54. 51%, 90. 00% sensitivity and 81. 25%, 84. 38% specificity respectively in diagnosis of AD. Conclusion : AD group had a significant decreased level of Aβ1-42 and an increased level of Aβ ratio, compared with NC group.
基金Specific public service sectors of agricultureresearch (200803020)
文摘Porcine reproductive and respiratory syndrome is caused by the PRRS virus (PRRSV),which has six structural proteins (GP2,GP3,GP4,GP5,M and N). GP5 and N protein are important targets for serological detection by enzyme-linked immunosorbent assay (ELISA) and other methods. Toward this goal,we developed an indirect ELISA with recombinant GP5 antigens and this method was validated by comparison to the LSI PRRSV-Ab ELISA kit. The results indicated that the optimal concentration of coated recombinant antigen was 0.2 μg/well for a serum dilution of 1:40. The rate of agreement with the LSI PRRSV-Ab kit was 88.7% (266/300). These results support the potential use of recombinant GP5 as an antigen for indirect ELISA to detect PRRSV antibodies in pigs.
基金Supported by Fund for Scientific Research of Overseas Chinese Students by Beijing Personnel Bureau
文摘Objective To detect the change of nerve growth factor (NGF) level in human amniotic fluid during gestation, and to explore the relationship between this change and fetal ventriculo-megaly (VM). Methods The studied subjects (collected from 2004 to 2007) were divided into four groups, including the second-trimester pregnancy group (n=113), third-trimester pregnancy group (n=110), fetal cerebral VM group (n=12), and healthy control group (n=12) which matched with the VM group in gestational weeks. The amniotic fluid specimens were obtained during amniocentesis or cesarean section. The NGF levels in amniotic fluid were detected with en-zyme-linked immunosorbent assay. Results A significantly negative correlation was found between gestational age and the NGF level in amniotic fluid (r= 0.6149, P<0.0001). The NGF level in patients with fetal VM was significantly lower than that in healthy controls (33.95±29.24 pg/mL vs. 64.73±16.21 pg/mL, P=0.024). Conclusion NGF levels in amniotic fluid may be a sensitive marker for fetal VM.
基金This research was supported by National 863 High Technology Research Foundation of China(2002AA62601)National Natural Science Foundation of China(30170726)+1 种基金the Project of Chinese Academy of Sciences(KSCXZ-SW-302)the Innovation Project of the Institute of Hydrobiology,Chinese Academy of Sciences.
文摘Grass carp plays an important role in small-scale aquaculture in Vietnam. However, a severe disease, known in Vietnam as "Red Spot Disease", is causing significant economic loss in grass carp aquaculture. In this study, the tissue samples isolated from the grass carp with Red Spot Disease in Vietnam are investigated and comparied with the control GCHV isolated in China by experimental infection, culture cell infection, serological cross reactivity, and RT-PCR amplification. Infected grass carp exhibits hemorrhage symptoms about 5 days after experimental injection with GCHV-V (Vietnam) strain. The symptoms and lethality induced by the GCHV-V strain are identical to that induced by the Chinese GCHV-9014 strain. The Chinese GCHV-873 strain induces typical cytopathogenic effects in 4 cell lines, such as CIK, CAB, FHM and GCO, from the 6 fish cell lines examined. No cytopathogenic effects are observed in all the 6 examined cell lines, including CAB, FHM, CIK, EPC, CCO and GCO, infected by the GCHV-V strain and GCHV-9014 strain. Immunodiffusion assays demonstrate an obvious cross-reactivity among three GCHV strains. Precipitin lines are clearly observed not only between the anti-GCHV-873 serum and the two strains GCHV-873 and GCHV-9014, but also between the anti-GCHV-873 serum and the GCHV-V strain. GCHV can be detected by immunodiffusion assays after three generations of blind propagations in the cell lines inoculated by GCHV-V strain. This implicates that GCHV-V viruses have been replicated and amplified despite there being no cytopathogenic effects observed in these examined cell lines. Three genome segments of GCHV, including S8, S9 and S10, are amplified by three sets of PCR primers designed according to the segment sequences published recently. The Q8fp and Q8rp primer set specific for genome segment S8 amplifies a 955 bp fragment from the extracted sample of diseased fish with Red Spot Disease, and the fragment size is identical to that amplified by the same primer set from control GCHV-873 strain. Simultaneously, the Q9fp and Q9rp primer set specific for genome segment S9 generates a same 635 bp product, and the Q10fp and Q10rp primer set specific for genome segment S10 produces a same 697 bp fragment from both template samples of diseased fish with Red Spot Disease and control GCHV-873 strain. The RT-PCR amplification and corresponding size comparison data indicate that the three GCHV-V genome segments extracted from the diseased grass carp with Red Spot Disease in Vietnam should be identical to that in control GCHV-873 strain from China. The data confirm that the causative agent of grass carp Red Spot Disease in Vietnam is a virus, and the virus is closely similar to GCHV strain in China.
基金Supported by Grants from Guangdong Natural Science Foundation Project,5004750National Key Development Project,973 Program 2002CB513206
文摘AIM： To detect and evaluate the antibodies against Helicobacter pylori （H pylori） neutrophil-activating protein （HP-NAP） in patients with gastric cancer and other gastroduodenal diseases.METHODS： Recombinant HP-NAP was prepared from a prokaryotic expression system in Escherichia coll. Serum positivity and level of HP-NAP-specific antibodies in sera from 43 patients with gastric cancer, 28 with chronic gastritis, 28 with peptic ulcer, and 89 healthy controls were measured by rHP-NAP-based ELISA. rHP-NAP-stimulated production of interleukin-8 （IL-8） and growth-related oncogene （GROα） cytokines in the culture supernatant of SGC7901 gastric epithelial cells was also detected.RESULTS： The serum positivity and mean absorbancevalue of HP-NAP-specific antibodies in the gastriccancer group （97.7% and 1.01 ± 0.24） were significantly higher than those in the chronic gastritisgroup （85.7% and 0.89 ± 0.14, P 〈 0.005） and healthy control group （27.7% and 0.65 ± 0.18, P 〈 0.001）. The sensitivity and specificity of ELISA for the detection of HP-NAP-specific antibodies were 95.5% and 91.5%, respectively. HP-NAP could slightly upregulate IL-8 production in gastric epithelial cell lines but had no effect on GROα production.CONCLUSION： Infection with virulent H py/ori strains secreting HP-NAP is associated with severe gastroduodenal diseases, and HP-NAP may play a role in the development of gastric carcinoma, rHP-NAP- based ELISA can be used as a new method to detect H pylori infection. The direct effect of HP-NAP on gastric epithelial cells may be limited, but HP-NAP may contribute to inflammatory response or carcinogenesis by activating neutrophils.
基金supported by the National High Technology Research and Development Program of China (Granted no. 2011AA10A216)Special Fund for Agroscientific Research in the Public Interest (Granted no. 201203085)
文摘Malachite green(MG), a dye, is an antifungal agent that has been used to treat and prevent fish diseases. It is metabolized into reduced leucomalachite green forms(LMG) that may reside in fish muscles for a long period, thus being harmful to human health. The aim of this study was to develop a competitive and direct enzyme-linked immunosorbent assay(ELISA) to detect MG and LMG specifically. The monoclonal antibody(m Ab) to LMG was generated using a hybridoma technique. The obtained m Ab showed good cross-reactivity(CR) to malachite green(MG), but not to crystal violet(CV) and Brilliant Green(BG). The m Ab was used to develop a fast detecting ELISA of MG and LMG in fish. By introducing the conjugation LMG-HRP, the detection capability was 0.37 ng m L-1 for MG and LMG. The mean recovery from spiked grass carp tissues ranged from 76.2% to 82.9% and the coefficients of variation varied between 1.8% and 7.5%. The stable and efficient monoclonal cell line obtained is a sustainable source of sensitive and specific antibody to MG and LMG.
