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  1. Article ; Online: Waste Eggshells as a Natural Filler for the Poly(Vinyl Chloride) Composites.

    Skórczewska, Katarzyna / Lewandowski, Krzysztof / Szewczykowski, Piotr / Wilczewski, Sławomir / Szulc, Joanna / Stopa, Paulina / Nowakowska, Paulina

    Polymers

    2022  Volume 14, Issue 20

    Abstract: The paper presents the characteristics of unplasticized PVC composites modified with biofiller obtained from the waste eggshells of hen eggs. The composites obtained by extrusion contained from 10 phr to 40 phr of biofiller. The filler was characterized ... ...

    Abstract The paper presents the characteristics of unplasticized PVC composites modified with biofiller obtained from the waste eggshells of hen eggs. The composites obtained by extrusion contained from 10 phr to 40 phr of biofiller. The filler was characterized using the SEM, TG, and sieve analysis methods. The influence of the filler on the processing properties was determined using plastographometric and MFR tests. Fundamental analysis of mechanical properties was also performed, i.e., Charpy impact strength and determination of tensile properties. The mechanical properties were supported with dynamical mechanical thermal analysis, time of thermal stability, and thermogravimetric analysis. Structure analysis was also performed using SEM and X-ray microcomputed tomography (micro-CT). The processing properties of the tested composites do not give grounds for disqualifying such material from traditional processing PVC mixtures. Notably, the biofiller significantly improves thermal stability. Ground eggshells (ES) work as scavengers for the Cl radicals released in the first stage, which delays the PVC chain's decay. Additionally, a significant increase in the value of the modulus of elasticity and softening point (VST) of the composites concerning PVC was found. Ground hen eggshells can be used as an effective filler for PVC composites.
    Language English
    Publishing date 2022-10-17
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2527146-5
    ISSN 2073-4360 ; 2073-4360
    ISSN (online) 2073-4360
    ISSN 2073-4360
    DOI 10.3390/polym14204372
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: The flow cytometry of Bacillus anthracis spores revisited.

    Stopa, P J

    Cytometry

    2000  Volume 41, Issue 4, Page(s) 237–244

    Abstract: Background: The potential use of Bacillus anthracis spores as a weapon of terror has rekindled interest in the rapid detection and identification of the spores of these bacteria. Prior efforts to utilize flow cytometry (FCM) for this purpose resulted in ...

    Abstract Background: The potential use of Bacillus anthracis spores as a weapon of terror has rekindled interest in the rapid detection and identification of the spores of these bacteria. Prior efforts to utilize flow cytometry (FCM) for this purpose resulted in tedious and time-consuming protocols. Advances in rapid immunoassays suggest a reinvestigation of the use of FCM because this may allow for the development of a rapid and sensitive system for detection and/or identification of spores in suspect samples.
    Methods: In this study, antiserum was raised in goats using three different strains of B. anthracis spores as the immunogen. The resultant antibodies were purified, labeled with fluorescein, and evaluated for use in an immunoassay on a Coulter Epics XL flow cytometer. In the protocol that was developed, fluorescein-labeled antibodies are simply mixed with the sample, allowed to incubate, and then analyzed on the flow cytometer. Washes and centrifugation were eliminated.
    Results: The results showed that a rapid (5 min) and sensitive immunological analysis was feasible. The detection limit (approximately 10(3) colony-forming units [CFU]/ ml) varied with strain, but there was no difference in the detection limit between live and irradiated spores. In addition, the power of FCM was utilized to minimize false-positive reactions among similar species of Bacillus by placing constraints on scatter and fluorescence intensity. The data also suggest that scatter might be useful to determine spore viability.
    Conclusion: This study shows that FCM may be an effective platform on which to perform immunological analysis for the detection and/or presumptive identification of B. anthracis spores. Published 2000 Wiley-Liss, Inc.
    MeSH term(s) Animals ; Antibodies, Bacterial/immunology ; Antibodies, Bacterial/isolation & purification ; Bacillus anthracis/cytology ; Bacillus anthracis/immunology ; Bacillus anthracis/isolation & purification ; Bacillus anthracis/radiation effects ; Biological Warfare ; Colony Count, Microbial ; Flow Cytometry/methods ; Fluorescein-5-isothiocyanate ; Fluorescence ; Gamma Rays ; Goats ; Immune Sera/immunology ; Immune Sera/isolation & purification ; Immunoassay/methods ; Sensitivity and Specificity ; Spores, Bacterial/cytology ; Spores, Bacterial/immunology ; Spores, Bacterial/isolation & purification ; Spores, Bacterial/radiation effects
    Chemical Substances Antibodies, Bacterial ; Immune Sera ; Fluorescein-5-isothiocyanate (I223NX31W9)
    Language English
    Publishing date 2000-07-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 762338-0
    ISSN 0196-4763
    ISSN 0196-4763
    DOI 10.1002/1097-0320(20001201)41:4<237::aid-cyto1>3.0.co;2-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: The use of blue-excitable nucleic-acid dyes for the detection of bacteria in well water using a simple field fluorometer and a flow cytometer.

    Stopa, P J / Mastromanolis, S A

    Journal of microbiological methods

    2001  Volume 45, Issue 3, Page(s) 143–153

    Abstract: The blue-excitable nucleic acid dyes Coriphosphine O (CPO), YOYO-1, and YOPRO-1 were evaluated to rapidly detect the presence of bacteria in well water samples using a simple field fluorometer (Turner Designs, Sunnyvale, CA, Model 10-AU-005) and a ... ...

    Abstract The blue-excitable nucleic acid dyes Coriphosphine O (CPO), YOYO-1, and YOPRO-1 were evaluated to rapidly detect the presence of bacteria in well water samples using a simple field fluorometer (Turner Designs, Sunnyvale, CA, Model 10-AU-005) and a tabletop flow cytometer (Coulter Epics XL). The dyes were first titrated on the Turner Designs Model 10-AU field fluorometer with log-fold dilutions of Esherichia coli, since this organism is the indicator organism for water contamination. A detection limit of 10(4) Colony Forming Units per ml (CFU/ml) was established for YOPRO-1 and 10(5) CFU/ml for YOYO-1. The detection limit with CPO was determined to be 10(7) CFU/ml due to the high background fluorescence of the dye. The dyes were also evaluated with ragweed pollen to gauge the effect of a biological interferent. Ten well-water samples were subsequently analyzed using the technique. The results showed that only YOYO-1 correctly detected all the samples that were positive according to the reference laboratory. YOPRO-1 correctly detected only one of four positive samples. Analysis with the CPO dye was inconclusive due to high background fluorescence. The samples were then subjected to analysis on the flow cytometer. Results obtained with YOYO-1 compared well to those obtained on the fluorometer and by the reference techniques. YOPRO-1 performed better on the flow cytometer than with the simple fluorometer, correctly detecting three of four positive samples. Although the CPO results showed a very slight increase of green fluorescence with positive samples, they were largely indistinguishable from negative samples. This study suggests YOYO-1 could be useful with either a simple fluorometer or with a tabletop flow cytometer in screening water samples for the presence of bacterial contamination.
    MeSH term(s) Bacteria/isolation & purification ; Coloring Agents ; Escherichia coli/isolation & purification ; Flow Cytometry/methods ; Fluorometry/methods ; Nucleic Acids/analysis ; Water Microbiology
    Chemical Substances Coloring Agents ; Nucleic Acids
    Language English
    Publishing date 2001-05-01
    Publishing country Netherlands
    Document type Evaluation Studies ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 604916-3
    ISSN 1872-8359 ; 0167-7012
    ISSN (online) 1872-8359
    ISSN 0167-7012
    DOI 10.1016/s0167-7012(01)00252-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Application of an immunomagnetic assay system for detection of virulent bacteria in biological samples

    Yu, H / Stopa, P.J

    Environmental immunochemical methods : perspectives and applications /

    1996  

    Abstract: Virulent pathogenic bacteria could pose a serious health threat in contaminated food and water resources. Traditional bacterial culture methods or enzyme linked immunosorbent assay (ELISA) for identification of the bacteria are time consuming and labor ... ...

    Abstract Virulent pathogenic bacteria could pose a serious health threat in contaminated food and water resources. Traditional bacterial culture methods or enzyme linked immunosorbent assay (ELISA) for identification of the bacteria are time consuming and labor intensive. Some new technologies are very sensitive but analysis time can be lengthy. For example, the polymerase chain reaction (PCR) can be used to amplify small quantities of genetic material to determine the presence of bacteria. This is a sensitive method that requires pure samples and considerable laboratory time. Alternative methods should be quicker and retain sensitivity. The magnetic separation technique appears promising for rapid bacterial isolation from the media prior to the detection. In this work, immunomagnetic assay system (IMAS) has been coupled to an electrochemiluminescent (ECL) technology for rapid and sensitive bacterial detection of biological samples within an hour. The sensitivity of the IMAS-ECL for Bacillus anthrax spores (sterne), Escherichia coli O157:H7 and Salmonella typhimurium detection is about 1000 cells/mL in biological samples. In addition, IMAS can also be coupled to a flow cytometer or any analytical instruments for target agent monitoring. Results of this study strongly suggest that IMAS methodology is useful for rapid and sensitive detection.
    Keywords food contamination
    Language English
    Size p. 297-306.
    Publisher American Chemical Society, c1996.
    Publishing place Washington, DC
    Document type Article
    Note Developed from a symposium sponsored by the U.S. Environmental Protection Agency at the National Immunochemistry Summit IV, August 2-3, 1995, Las Vegas, Nevada.
    ISBN 084123454X ; 9780841234543
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: Levels of aqueous humor trace elements in patients with non-exsudative age-related macular degeneration: a case-control study.

    Jünemann, Anselm G M / Stopa, Piotr / Michalke, Bernhard / Chaudhri, Anwar / Reulbach, Udo / Huchzermeyer, Cord / Schlötzer-Schrehardt, Ursula / Kruse, Friedrich E / Zrenner, Eberhart / Rejdak, Robert

    PloS one

    2013  Volume 8, Issue 2, Page(s) e56734

    Abstract: Trace elements might play a role in the complex multifactorial pathogenesis of age-related macular degeneration (AMD). The aim of this study was to measure alterations of trace elements levels in aqueous humor of patients with non-exsudative (dry) AMD. ... ...

    Abstract Trace elements might play a role in the complex multifactorial pathogenesis of age-related macular degeneration (AMD). The aim of this study was to measure alterations of trace elements levels in aqueous humor of patients with non-exsudative (dry) AMD. For this pilot study, aqueous humor samples were collected from patients undergoing cataract surgery. 12 patients with dry AMD (age 77.9±6.62, female 8, male 4) and 11 patients without AMD (age 66.6±16.7, female 7, male 4) were included. Aqueous levels of cadmium, cobalt, copper, iron, manganese, selenium, and zinc were measured by use of Flow-Injection-Inductively-Coupled-Plasma-Mass-Spectrometry (FI-ICP-MS), quality controlled with certified standards. Patients with AMD had significantly higher aqueous humor levels of cadmium (median: 0.70 µmol/L, IQR: 0.40-0.84 vs. 0.06 µmol/L; IQR: 0.01-.018; p = 0.002), cobalt (median: 3.1 µmol/L, IQR: 2.62-3.15 vs. 1.17 µmol/L; IQR: 0.95-1.27; p<0.001), iron (median: 311 µmol/L, IQR: 289-329 vs. 129 µmol/L; IQR: 111-145; p<0.001) and zinc (median: 23.1 µmol/L, IQR: 12.9-32.6 vs. 5.1 µmol/L; IQR: 4.4-9.4; p = 0.020) when compared with patients without AMD. Copper levels were significantly reduced in patients with AMD (median: 16.2 µmol/L, IQR: 11.4-31.3 vs. 49.9 µmol/L; IQR: 32.0-.142.0; p = 0.022) when compared to those without. No significant differences were observed in aqueous humor levels of manganese and selenium between patients with and without AMD. After an adjustment for multiple testing, cadmium, cobalt, copper and iron remained a significant factor in GLM models (adjusted for age and gender of the patients) for AMD. Alterations of trace element levels support the hypothesis that cadmium, cobalt, iron, and copper are involved in the pathogenesis of AMD.
    MeSH term(s) Aged ; Aqueous Humor/metabolism ; Case-Control Studies ; Female ; Humans ; Macular Degeneration/metabolism ; Male ; Trace Elements/metabolism
    Chemical Substances Trace Elements
    Language English
    Publishing date 2013-02-15
    Publishing country United States
    Document type Journal Article
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0056734
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Highly selective acridine and ethidium staining of bacterial DNA and RNA.

    Bruno, J G / Sincock, S A / Stopa, P J

    Biotechnic & histochemistry : official publication of the Biological Stain Commission

    1996  Volume 71, Issue 3, Page(s) 130–136

    Abstract: The acridine dyes acridine orange (AO) and coriphosphine O (CPO) and ethidium bromide (EtBr) were used to stain bacterial digests after electrophoresis in native and denaturing (SDS) polyacrylamide gels and were shown to stain DNA and RNA preferentially ... ...

    Abstract The acridine dyes acridine orange (AO) and coriphosphine O (CPO) and ethidium bromide (EtBr) were used to stain bacterial digests after electrophoresis in native and denaturing (SDS) polyacrylamide gels and were shown to stain DNA and RNA preferentially over other subcellular components in the gels. Vegetative cell digests of Bacillus subtilis, Escherichia coli, Micrococcus luteus, and Staphylococcus aureus showed intense staining of DNA with AO and CPO near the top of the gel, but little or no staining of other cellular constituents. EtBr stained both DNA and RNA in the gels. Protein standards and non-nucleic acid cellular constituents stained faintly with high concentrations (> or = 100 microM) of AO, lower concentrations (13.9 microM) of CPO, and did not stain with 0.5 microgram/ml EtBr in denaturing gels. The complete set of cellular biochemicals was visualized by silver staining, while the protein subset was detected by Coomassie blue staining. The highest concentrations of AO (120 microM) and CPO (13.9 microM) were shown to detect purified DNA in gels with a sensitivity in the range of 25-50 ng per band. This work demonstrates the specificity of acridine and ethidium dyes for nucleic acids, while illustrating the level of non-nucleic acid-specific interactions with other cellular components by staining of electrophoretically separated cellular components in a gel matrix.
    MeSH term(s) Acridine Orange/chemistry ; Aminoacridines/chemistry ; Bacillus subtilis/genetics ; DNA, Bacterial/analysis ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli/genetics ; Ethidium/chemistry ; Fluorescent Dyes/chemistry ; Micrococcus luteus/genetics ; Pseudomonas fluorescens/genetics ; RNA, Bacterial/analysis ; Staining and Labeling ; Staphylococcus aureus/genetics
    Chemical Substances Aminoacridines ; DNA, Bacterial ; Fluorescent Dyes ; RNA, Bacterial ; coriphosphine (5153-57-1) ; Ethidium (EN464416SI) ; Acridine Orange (F30N4O6XVV)
    Language English
    Publishing date 1996-05
    Publishing country England
    Document type Journal Article
    ZDB-ID 1069349-x
    ISSN 1473-7760 ; 1052-0295
    ISSN (online) 1473-7760
    ISSN 1052-0295
    DOI 10.3109/10520299609117149
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Neuroprotective effects of tempol on retinal ganglion cells in a partial optic nerve crush rat model with and without iron load.

    Thaler, Sebastian / Fiedorowicz, Michal / Rejdak, Robert / Choragiewicz, Tomasz J / Sulejczak, Dorota / Stopa, Piotr / Zarnowski, Tomasz / Zrenner, Eberhart / Grieb, Pawel / Schuettauf, Frank

    Experimental eye research

    2010  Volume 90, Issue 2, Page(s) 254–260

    Abstract: Iron overload can contribute to oxidative stress in many tissues. We studied the effects of pretreatment with iron dextran on RGC loss in a calibrated partial optic nerve crush (PONC) model in rats, along with the protection offered by tempol (4-hydroxy- ... ...

    Abstract Iron overload can contribute to oxidative stress in many tissues. We studied the effects of pretreatment with iron dextran on RGC loss in a calibrated partial optic nerve crush (PONC) model in rats, along with the protection offered by tempol (4-hydroxy-2,2,6,6-tetramethylpiperidinyl-1-oxyl, a membrane-permeable superoxide dismutase mimetic and free-radical scavenger), in the same experimental paradigm. A total of 40 rats in 6 groups of 5-8 animals each underwent PONC in one eye and sham crush in the other. Animals were pretreated with a single iron dextran load 24 h prior to PONC, and treated with tempol 6 h before and then once daily after PONC. Control animals were treated with PBS. RGC were retrogradely labeled with a fluorescent marker; all data are expressed in percent of the RGC count in the respective sham-treated eye. Immunohistochemistry was performed to visualize 3-nitrotyrosine, a marker of nitroxidative stress. PONC without iron pretreatment resulted in the survival of only 31.4% of labeled RGC after 7 days. Even fewer RGC (12.7%) survived after PONC with iron pretreatment. However, tempol in doses of 20 mg/kg of body weight (BW) significantly attenuated this effect when given as described above; in the group without iron pretreatment the number of surviving RGC doubled from 31.4% to 62.1%. In the group with iron pretreatment the survival rate of RGC increased even more pronouncedly, from 12.7% without tempol to 46.2% with tempol. Tempol in doses of 1 mg/kg BW and 5 mg/kg BW showed no significant rescue of RGC. Immunostaining showed nitrotyrosine-positive RGCs in PONC but not in sham-treated eyes and an increase in positive cells after iron load. Tempol treatment reduced nitrotyrosine staining in both the iron and non-iron groups. Our results demonstrate that PONC results in significantly greater RGC damage when iron pretreatment is performed, and that the compound tempol may provide additional protection for RGC in cases of neuronal damage both with and without prior iron treatment.
    MeSH term(s) Animals ; Antioxidants/administration & dosage ; Cell Count ; Cell Survival ; Cyclic N-Oxides/administration & dosage ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Hematinics/therapeutic use ; Immunoenzyme Techniques ; Iron Overload/metabolism ; Iron-Dextran Complex/therapeutic use ; Neuroprotective Agents/administration & dosage ; Optic Nerve Injuries/complications ; Oxidative Stress ; Rats ; Rats, Inbred BN ; Retinal Degeneration/etiology ; Retinal Degeneration/metabolism ; Retinal Degeneration/prevention & control ; Retinal Ganglion Cells/drug effects ; Retinal Ganglion Cells/metabolism ; Retinal Ganglion Cells/pathology ; Spin Labels ; Tyrosine/analogs & derivatives ; Tyrosine/metabolism
    Chemical Substances Antioxidants ; Cyclic N-Oxides ; Hematinics ; Neuroprotective Agents ; Spin Labels ; 3-nitrotyrosine (3604-79-3) ; Tyrosine (42HK56048U) ; Iron-Dextran Complex (9004-66-4) ; tempol (U78ZX2F65X)
    Language English
    Publishing date 2010-02
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 80122-7
    ISSN 1096-0007 ; 0014-4835
    ISSN (online) 1096-0007
    ISSN 0014-4835
    DOI 10.1016/j.exer.2009.10.013
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Comparison of seven enzyme immunoassay systems for measurement of cytomegalovirus.

    Yolken, R H / Stopa, P J

    Journal of clinical microbiology

    1980  Volume 11, Issue 6, Page(s) 546–551

    Abstract: The relative sensitivities of seven different enzyme immunoassay (EIA) systems for the measurement of cytomegalovirus (CMV) were compared. Methods which used two separate antisera to CMV provided the greatest degree of sensitivity. Equivalent sensitivity ...

    Abstract The relative sensitivities of seven different enzyme immunoassay (EIA) systems for the measurement of cytomegalovirus (CMV) were compared. Methods which used two separate antisera to CMV provided the greatest degree of sensitivity. Equivalent sensitivity was noted with the use of either enzyme-labeled antiglobulin or unlabeled staphylococcal protein A and rabbit enzyme-antienzyme complex to measure the second anti-CMV antibody bound to the solid phase. Single-antibody methods were less sensitive than the double-antibody methods but were more sensitive than an inhibition EIA. However, the sensitivity of the inhibition EIA was improved when CMV-antibody complexes were separated from unreacted antibody by means of precipitation with polyethylene glycol. Double-antibody EIA systems are preferable when antisera prepared in two different animal species are obtainable. However, a number of single-antibody EIA systems can be formulated for use in situations where only a single antiserum is available.
    MeSH term(s) Antibodies, Viral/analysis ; Cytomegalovirus/immunology ; Immunoenzyme Techniques
    Chemical Substances Antibodies, Viral
    Language English
    Publishing date 1980-06
    Publishing country United States
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 390499-4
    ISSN 1098-660X ; 0095-1137
    ISSN (online) 1098-660X
    ISSN 0095-1137
    DOI 10.1128/jcm.11.6.546-551.1980
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Enzyme-linked fluorescence assay: Ultrasensitive solid-phase assay for detection of human rotavirus.

    Yolken, R H / Stopa, P J

    Journal of clinical microbiology

    1979  Volume 10, Issue 3, Page(s) 317–321

    Abstract: Enzyme-linked immunosorbent assay (ELISA) has proven to be a useful assay system for the direct detection of infectious agents. However, when the usual color-producing substrates are employed, relatively large amounts of substrate must be hydrolyzed by ... ...

    Abstract Enzyme-linked immunosorbent assay (ELISA) has proven to be a useful assay system for the direct detection of infectious agents. However, when the usual color-producing substrates are employed, relatively large amounts of substrate must be hydrolyzed by the bound enzyme before detection can be achieved. We attempted to improve the sensitivity of ELISA by utilizing a substrate that yields a fluorescent product on enzyme action. The enzyme-linked fluorescence assay (ELFA) based on this principle was approximately 100 times more sensitive than the corresponding ELISA or radioimmunoassay for the detection of human rotavirus in a standard stool suspension. In addition, the ELFA for human rotavirus was capable of detecting antigen in six specimens that were negative by ELISA. Five of these specimens were obtained late in the course of confirmed rotavirus infections. ELFA provides a simple, reliable, ultrasensitive method for the rapid detection of viral antigen.
    MeSH term(s) Antigens, Viral/analysis ; Child ; Enzyme-Linked Immunosorbent Assay ; Feces/microbiology ; Fluorescence ; Humans ; Immunoenzyme Techniques ; RNA Viruses/immunology ; Rotavirus/immunology ; Virus Diseases/diagnosis ; Virus Diseases/immunology
    Chemical Substances Antigens, Viral
    Language English
    Publishing date 1979-09
    Publishing country United States
    Document type Comparative Study ; Journal Article
    ZDB-ID 390499-4
    ISSN 1098-660X ; 0095-1137
    ISSN (online) 1098-660X
    ISSN 0095-1137
    DOI 10.1128/jcm.10.3.317-321.1979
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Analysis of nonspecific reactions in enzyme-linked immunosorbent assay testing for human rotavirus.

    Yolken, R H / Stopa, P J

    Journal of clinical microbiology

    1979  Volume 10, Issue 5, Page(s) 703–707

    Abstract: Solid-phase enzyme immunoassays can be utilized to detect antigens directly in clinical specimens. However, a small number of stools which we tested for human rotavirus by enzyme-linked immunosorbent assay (ELISA) were found to have nonspecific activity ... ...

    Abstract Solid-phase enzyme immunoassays can be utilized to detect antigens directly in clinical specimens. However, a small number of stools which we tested for human rotavirus by enzyme-linked immunosorbent assay (ELISA) were found to have nonspecific activity in the absence of rotaviral antigen. Similar nonspecific activity was found in eight of eight sera which contained rheumatoid factor. This nonspecific activity was markedly reduced by pretreatment of the specimens with reducing agents, normal goat serum, and anti-human immunoglobulin M (IgM). Thus, it is likely that these specimens contain an IgM antibody capable of reacting nonspecifically with the other components of the assay. Although pretreatment with the mild reducing agent N-acetylcysteine markedly reduced this nonspecific activity, such treatment did not reduce the specific ELISA activity due to rotavirus. Other treatments did produce a reduction in specific activity. Thus pretreatment with N-acetylcysteine offers a practical means to increase the specificity of ELISA systems without reducing their sensitivity.
    MeSH term(s) Acetylcysteine/pharmacology ; Animals ; Antigens, Viral/analysis ; Enzyme-Linked Immunosorbent Assay ; Feces/immunology ; Feces/microbiology ; Gastroenteritis/microbiology ; Goats/immunology ; Humans ; Immune Sera ; Immunoenzyme Techniques ; Immunoglobulin M/immunology ; Mercaptoethanol/pharmacology ; RNA Viruses/immunology ; Rheumatoid Factor/immunology ; Rotavirus/immunology
    Chemical Substances Antigens, Viral ; Immune Sera ; Immunoglobulin M ; Mercaptoethanol (60-24-2) ; Rheumatoid Factor (9009-79-4) ; Acetylcysteine (WYQ7N0BPYC)
    Language English
    Publishing date 1979-11
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 390499-4
    ISSN 1098-660X ; 0095-1137
    ISSN (online) 1098-660X
    ISSN 0095-1137
    DOI 10.1128/jcm.10.5.703-707.1979
    Database MEDical Literature Analysis and Retrieval System OnLINE

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