Development of a polyclonal antibodies-based serological methods and a DIG-labelled DNA probe-based molecular method for detection of the Vicia cryptic virus-M in field plants

2021 ◽  
pp. 114331
Author(s):  
Kun Zhang ◽  
Xinjian Zhuang ◽  
Hongmei Xu ◽  
Haifeng Gan ◽  
Zhen He ◽  
...  
Author(s):  
Gary Bassell ◽  
Robert H. Singer

We have been investigating the spatial distribution of nucleic acids intracellularly using in situ hybridization. The use of non-isotopic nucleotide analogs incorporated into the DNA probe allows the detection of the probe at its site of hybridization within the cell. This approach therefore is compatible with the high resolution available by electron microscopy. Biotinated or digoxigenated probe can be detected by antibodies conjugated to colloidal gold. Because mRNA serves as a template for the probe fragments, the colloidal gold particles are detected as arrays which allow it to be unequivocally distinguished from background.


Author(s):  
Jorge Pecci Saavedra ◽  
Mark Connaughton ◽  
Juan José López ◽  
Alicia Brusco

The use of antibodies as labels for the localization of specific molecules in the nervous systan has been extensively applied in recent years. Both monoand polyclonal antibodies or antisera have been employed. The knowledge of the organization of neuronal connectivities, gliovascular relationships, glioneuronal relationships and other features of nerve tissue has greatly increased.A number of areas of the nervous systan have been analyzed in our laboratory, including the nuclei of the raphe system, the reticular formation, interpeduncular nucleus, substantia nigra, caudate nucleus, putamen, pallidum, spinal cord, pineal gland and others.From a technical point of view, a number of variables needed to be taken into account in order to obtain reliable and reproducible results. The design of the optimal conditions of tissue fixation, embedding, sectioning, dilution of antibodies, and adaptation of Sternberger PAP technique were sane of the parameters taken into account to optimize the results. It is critical that each step of the technique be defined for each particular case.


1987 ◽  
Vol 57 (01) ◽  
pp. 029-034 ◽  
Author(s):  
Göran Urdén ◽  
Joanna Chmielewska ◽  
Tomas Carlsson ◽  
Björn Wiman

SummaryPolyclonal antibodies have been raised against the inhibitor moiety in the purified complex between tissue plasminogen activator and its fast inhibitor (PA-inhibitor) in human plasma/ serum. A radioimmunoassay for quantitation of PA-inhibitor antigen was developed. The polyclonal antiserum and a previously described monoclonal antibody against the PA-inhibitor (14) have been used to study the immunological relationship between PA-inhibitors from plasma, serum, platelets, placenta extract and conditioned media from Hep G2 and HT 1080 cells. It was demonstrated that the ratio between PA-inhibitor activity and antigen varied considerably between the different sources. In the plasma samples studied, similar activity and antigen concentrations were found, suggesting that the PA-inhibitor in these samples mainly was in an active form. On the other hand the other sources seemed to contain variable amounts of inactive PA-inhibitor forms. Immunoadsorption experiments revealed that the PA-inhibitor (activity and antigen) from all the sources were specifically bound to the insolubilized antibodies (polyclonal and monoclonal). In no case, however, could active PA-inhibitor be eluted from the immunoadsorption columns. Also the competitive radioimmunoassays suggested that the PA-inhibitors from the different sources studied, were closely immunologically related.


1984 ◽  
Vol 52 (03) ◽  
pp. 250-252 ◽  
Author(s):  
Y Sultan ◽  
Ph Avner ◽  
P Maisonneuve ◽  
D Arnaud ◽  
Ch Jeanneau

SummaryTwo monoclonal antibodies raised against FVIII/von Willebrand protein were used in an immunoradiometric assay (IRMA) to measure this antigen in normal plasma and plasma of patients with different forms of von Willebrand’s disease. The first antibody, an IgG1 was used to coat polystyrene tubes, the second one, an IgG2a, iodinated and used in the second step. Both antibodies inhibit ristocetin induced platelet agglutination and react strongly with platelets, megacaryocytes and endothelial cells. The IRMA test using these antibodies showed greater sensitivity than that using rabbit polyclonal anti VIIIRAg antibodies. A good correlation between the two tests was nevertheless found when VIIIRAg was measured in the majority of patient’s plasma. However 5 patients from 3 different families showed more antigenic material in the rabbit antibody IRMA than in the monoclonal antibody IRMA. It is suggested therefore that the monoclonal antibodies identify part of the VIIIR:Ag molecule showing structural abnormalities in these vWd patients, these structural changes remaining undetected by the polyclonal antibodies.


2020 ◽  
Vol 21 (1) ◽  
pp. 6-9
Author(s):  
Wuye Ria Andayanie

Soybean superior varieties with high yields and are resistant to abiotic stress have been largely released, although some varieties grown in the field are not resistant to SMV. In addition, the opportunity to obtain lines of hope as prospective varieties with high yield and resistance to SMV is very small. The method for evaluating soybean germplasm is based on serological observations of 98 accessions of leaf samples from SMV inoculation with T isolate. The evaluation results of 98 accessions based on visual observations showed 31 genotypes reacting very resistant or healthy to mild resistant category to SMV T isolate  with a percentage of symptom severity of 0 −30 %. Among 31 genotypes there are 2 genotypes (PI 200485; M8Grb 44; Mlg 3288) with the category of visually very resistant and resistant, respectively and  Mlg 3288  with the category of mild resistant.  They have a good agronomic appearance with a weight of 100 seeds (˃10 g) and react negatively with polyclonal antibodies to SMV, except Mlg 3288 reaction is not consistent, despite the weight of 100 seeds (˃ 10 g). Leaf samples from 98 accessions revealed various symptoms of SMV infection in the field. This diversity of symptoms is caused by susceptibility to accession, when infection occurs, and environmental factors. Keywords—: soybean; genotipe; Soybean mosaic virus (SMV); disease severity; polyclonal  antibody


2019 ◽  
Vol 9 (01) ◽  
pp. 46-50
Author(s):  
Ashwak B Al-Hashimy ◽  
Huda S Alagely ◽  
Akeel K Albuaji ◽  
Khalid R Majeed

The present study included the collection of 100 samples from various clinical sources for investigating the presence of P. aeruginosa in those sources, the samples have been collected from some hospitals in Baghdad and Hillah city (Al-qassim General Hospital, ,Al-hillah teaching hospital,and Al-hashimya General hospital ) which included wounds, burns, ear and sputum infections. The study was carried out through October 2017 till the end of March 2018. The samples were identified based on the morphological and microscopically characteristics of the colonies when they were culturing or number of culture media as well as biochemical tests, molecular identification were also used as a final diagnostic test for isolates that were positive as they belong to P.aeruginosa bacteria during previous tests based on the OprD gene which has specific sequences for P.aeruginosa bacteria as a detection gene and also consider as virulence factor so it have a synonyms mechanism to antibiotic resistance . The results of the final diagnosis showed that 38 isolates belong to target bacteria were distributed as 18 of burns, 11 isolates of wounds, 6 isolates of ear infection and 3 isolates of sputum, The examination of the sensitivity of all bacterial isolates was done for elected 38 isolation towards the 9 antibiotic by a Bauer - Kirby and the isolates were resistant for a number of antibiotics used such as Ciprofloxacin 65.7%, Norflaxacin 71%, Imipenem 63.1% Meropenem 68.4%, Gentamicin 65.7%, Amikacin 26.3%, Cefepime 68.4%, Ceftazidime 65.7% and Piperacillin 57.8%.Molecular method , All isolates (38) of P. aeruginosa positive for the diagnostic special gene (OprD) genes (100%).


2019 ◽  
Vol 13 (1) ◽  
pp. 137-145 ◽  
Author(s):  
Tzonka Godjevargova ◽  
Zlatina Becheva ◽  
Yavor Ivanov ◽  
Andrey Tchorbanov

Objectives: Staphylococcus aureus is a Gram-positive microorganism. S. aureus can grow in various foods and cause food poisoning by secreting enterotoxins. The most common enterotoxins involved in food poisoning are staphylococcal enterotoxin A and staphylococcal enterotoxin B, but Staphylococcal Enterotoxin A (SEA) is predominant. The main types of food contaminated with SEs are meat and meat products, poultry and eggs, milk and dairy products. The aim of this study was to develop a rapid and sensitive fluorescence immunoassay for detection of staphylococcal enterotoxin A in milk. Methods: Monoclonal and polyclonal antibodies for SEA were produced and characterized. Competitive fluorescence immunoassay based on Magnetic Nanoparticles (MNPs) was performed and optimized. MNPs were used as a solid carrier of the antibodies. The first step of the assay was immunoreaction between the immobilized antibody onto MNPs and SEA in milk sample. Then the fluorescein-SEA conjugate was added to the sample. Thus, competitive immunoreaction between MNP-mAb/MNP-pAb with SEA and SEA-FITC was performed. These immuno-complexes were separated by a magnetic separator and the obtained supernatants were analyzed. The fluorescent signal from the excess of conjugated SEA was proportional to the SEA contained in the milk. The assay duration was only 30 min. Results: The fluorescence immunoassays performed with polyclonal antibody had linear ranges from 5 pg/mL to 100 ng/mL SEA in a buffer, and from 50 pg/mL to 50 ng/mL SEA in spiked milk samples. While the same assays performed with monoclonal antibody had linear ranges from 1 pg/mL to 20 ng/mL SEA in buffer, and from 10 pg/mL to 10 ng/mL SEA in spiked milk samples. The detection limits of the developed immunoassays performed in milk were: 48 pg/mL with polyclonal antibody and 9 pg/mL with monoclonal antibody. Conclusion: A rapid and sensitive fluorescence immunoassay based on magnetic nanoparticles with a polyclonal and monoclonal antibody for determination of staphylococcal enterotoxin A in milk was developed.


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