scholarly journals Limited specificity of commercially available SARS‐CoV‐2 IgG ELISAs in serum samples of African origin

2021 ◽  
Author(s):  
Petra Emmerich ◽  
Carolin Murawski ◽  
Christa Ehmen ◽  
Ronald Possel ◽  
Neele Pekarek ◽  
...  
Keyword(s):  
African Origin ◽  
Serum Samples

scholarly journals Limited specificity of commercially available SARS-CoV-2 IgG ELISAs in serum samples of African origin

2020 ◽  
Author(s):  
Petra Emmerich ◽  
Carolin Murawski ◽  
Christa Ehmen ◽  
Ronald von Possel ◽  
Neele Pekarek ◽  
...  
Keyword(s):  
Immune Responses ◽  
False Positive ◽  
African Origin ◽  
Serum Samples ◽  
African Countries ◽  
Serological Tests

ABSTRACTSpecific serological tests are mandatory for reliable SARS-CoV-2 seroprevalence studies but assay specificity may vary considerably between populations due to interference of immune responses to other pathogens. Here, we assess the false positive rates obtained with four commercially available IgG ELISAs in serum/plasma panels originating from three different African countries.Article summary lineSeveral commercially available SARS-CoV-2 ELISAs show limited specificity when applied to serum panels of African origin.

Anticardiolipin Antibodies Are Elevated in HIV-1 Infected Haemophiliacs but Do Not Predict for Disease Progression

1989 ◽  
Vol 61 (01) ◽  
pp. 081-085 ◽  
Author(s):  
Simon Panzer ◽  
Christoph Stain ◽  
Hubert Hartl ◽  
Robert Dudczak ◽  
Klaus Lechner
Keyword(s):  
Normal Values ◽  
Anticardiolipin Antibodies ◽  
Haemophilia A ◽  
Serum Samples ◽  
Factor Viii Concentrates ◽  
Patient Groups ◽  
Anti Hiv ◽  
Hiv 1 ◽  
Cd4 Lymphocytes

SummaryLevels of anticardiolipin antibodies (ACA) were measured in 55 patients with haemophilia A in serum samples obtained in 1983 and in 1987. Twenty-one patients were negative for anti HIV-1 antibodies in 1983 and remained negative in 1987; 34 patients had anti HIV-1 antibodies in 1983; 17 of these latter patients remained asymptomatic, whereas 17 patients developed ARC or AIDS during the 4 years follow-up. Thirteen anti HIV-1 negative patients had elevated ACA levels in 1983; subsequently, a significant decrease was observed in all these subjects (p <0.001). All anti HIV-1 positive patients had elevated ACA levels in 1983; normal values were found in 9 patients in 1987. Yet, these changes were not significant (p >0.05). ACA levels were significantly higher in HIV-1 infected patients than in those without anti HIV-1 antibodies (p <0.05). There was no difference of ACA levels between the two anti HIV-1 positive patient groups, be it in 1983 or be it in 1987 (p >0.05). There was no correlation of ACA levels with serum IgG concentrations, CD4+ lymphocytes, or the consumption of factor VIII concentrates.

Immunologic Assessment of Patients Treated with Bovine Fibrin as a Hemostatic Agent

1996 ◽  
Vol 76 (06) ◽  
pp. 0925-0931 ◽  
Author(s):  
John F Carroll ◽  
Keith A Moskowitz ◽  
Niloo M Edwards ◽  
Thomas J Hickey ◽  
Eric A Rose ◽  
...  
Keyword(s):  
Coagulation Factors ◽  
Allergic Reactions ◽  
Factor V ◽  
Normal Range ◽  
Serum Samples ◽  
Human Fibrinogen ◽  
Bovine Thrombin ◽  
Thrombotic Complications ◽  
The Mean ◽  
Clinically Significant

SummaryTwenty-one cardiothoracic surgical patients have been treated with fibrin as a topical hemostatic/sealing agent, prepared from bovine fibrinogen clotted with bovine thrombin. Serum samples have been collected before treatment with fibrin and postoperatively between 1 and 9 days, 3 and 12 weeks, and 6 and 8 months. The titers of anti-bovine fibrinogen antibodies, measured by ELISA specific for immunoglobulins IgG or IgM, increased to maximal values after about 8 or 6 weeks, respectively. After 8 months, IgG titers were on average 20-fold lower than the mean maximal value, while IgM titers returned to the normal range. IgG was the predominant anti-bovine fibrinogen immunoglobulin as documented by ELISA, affinity chromatography and electrophoresis. Anti-bovine fibrinogen antibodies present in patients reacted readily with bovine fibrinogen, but did not cross-react with human fibrinogen as measured by ELISA or by immunoelectrophoresis. A significant amount of antibodies against bovine thrombin and factor V has been found, many cross-reacting with the human counterparts. No hemorrhagic or thrombotic complications, or clinically significant allergic reactions, occurred in any patient, in spite of antibody presence against some bovine and human coagulation factors. The treatment of patients with bovine fibrin, without induction of immunologic response against human fibrinogen, appeared to be an effective topical hemostatic/sealing measure.

Autoantibodies to Thrombomodulin: Development of an Enzyme Immunoassay and a Survey of their Frequency in Patients with the Lupus Anticoagulant

1992 ◽  
Vol 67 (05) ◽  
pp. 507-509 ◽  
Author(s):  
John Gibson ◽  
Margaret Nelson ◽  
Ross Brown ◽  
Hatem Salem ◽  
Harry Kronenberg
Keyword(s):  
Enzyme Immunoassay ◽  
Lupus Anticoagulant ◽  
Specific Binding ◽  
Technical Problem ◽  
Serum Samples ◽  
Citrate Buffer ◽  
The Mean ◽  
Sample Dilution ◽  
Negative Population ◽  
Serum Components

SummaryIn order to investigate the possibility that autoantibodies to thrombomodulin (TM) may exist in patients with the lupus anticoagulant (LA) and perhaps be implicated in the pathogenesis of recurrent thrombosis seen in such patients, we developed an enzyme-immunoassay to screen serum samples for anti-human TM activity. The major technical problem encountered in developing this assay was to reduce the non-specific binding of serum components from both the LA positive and the negative population. Considerable reduction of non-specific binding was achieved by use of a phosphate/citrate buffer at pH 8.0 and the use of an optimal sample dilution of 1/40. In addition, samples were always tested in parallel in blank wells and results are expressed as an OD ratio. Samples from 113 patients with the LA were assayed and compared to 78 patients referred for LA testing but found to be negative. The mean OD values for the LA positive patients (± SD) was 1.36 (0.44) with a range of 0.78-2.57. This was virtually identical to the values for the LA negative population (1.38 ± 0.40, range 0.76-2.77). The results of this study indicate that there is no evidence for the presence of a significant autoantibody activity to TM in patients with the LA when compared to LA negative patients. If such autoantibodies do exist their frequency must be quite low.

Study the Relationship Between Estrogen Hormone and Calcium in Normal Females Before and After Menopause in Baghdad / Iraq

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Sameerah Mustafa ◽  
Asal Tawfeeq ◽  
Hadeel Hasan
Keyword(s):  
Oral Contraceptive ◽  
Healthy Controls ◽  
Serum Samples ◽  
Oral Contraceptive Pills ◽  
Contraceptive Pills ◽  
Menopausal Women ◽  
Before And After ◽  
Group A ◽  
Group B ◽  
Age Range

This study involved the collection of (90) samples of women serum which included (30) serum samples collected from women before menopause (reproductive women) in the age range of (22-43) years and were considered as (group A- control). While, (group B) included (30) serum samples collected from women using oral contraceptive pills between the ages of (22-43) years old. Whereas, another (30) serum samples were collected from women after menopause between the ages of (43-54) years and were considered as (group C). All of the collected serum samples were subjected to a number of serological and chemical tests for the measurement of (E2, HDL, LDL and Ca). Then, the obtained data were statistical analyzed and results showed a significant decrease (p˂ 0.05) in (E2 ,Ca and HDL) levels in menopausal women compared to that of the normal healthy controls. While, there were non-significant decrease (p> 0.05) in (E2, Ca and HDL) levels in women taking oral contraceptive when compared to the normal healthy controls. On the other hand, a significant increase (p˂ 0.05) was recorded in LDL level in menopausal women compared to that of the normal healthy controls whereas, no-significant increase (p˃ 0.05) in the LDL level in women taking oral contraceptives when compared to the control women.

TO DETERMINE THE ROLE OF CA125 IN THE DIAGNOSIS OF ACUTE APPENDICITIS

2020 ◽  
Vol 4 (7) ◽  
Author(s):  
Vinod Kumar ◽  
Bhupen Songra ◽  
Richa Jain ◽  
Deeksha Mehta
Keyword(s):  
Acute Appendicitis ◽  
Clinical Diagnosis ◽  
Tertiary Care Hospital ◽  
Tertiary Care ◽  
Ca 125 ◽  
Care Hospital ◽  
Serum Samples ◽  
Roc Curve Analysis ◽  
Surgery Department

Background: the present study was under taken to determine the role of CA-125 in the diagnosis of acute appendicitis (AA), to prevent its complications and also in preventing negative appendicectomies in tertiary care hospital. Methods: The study was conducted at a tertiary care and research center between 01/03/2018 to 30/06/2019. Patients admitted to the surgery department with diagnosis of AA were considered for the study. After informed consent, a, standardized history was obtained as a case Performa. Serum samples from all the cases with clinical diagnosis of AA were obtained and stored. Only the cases with histopathologically approved AA were included in the study. Cases operated for clinical diagnosis of AA, but not histopathologically proven AA was not included in the study. CA125 levels in cases with definitive diagnosis of AA were measured. Results: In present study, ROC curve analysis revealed the sensitivity of 87.27 % and specificity of 90.91 % when the CA 125 cut-off value of > 16.8 was taken to diagnose acute appendicitis. AUC was 0.911 with a standard error of 0.0292. Conclusion: In this study we have observed that CA125 showed a positive correlation with acute appendicitis, that was statistically not significant (P>0.05). We didn’t evaluate the correlation with the disease severity. We consider that CA125 can be used as a marker in acute appendicitis cases although further research is still needed. Keywords: CA125, Acute Appendicitis, Surgery.

TBE in Sweden

2020 ◽  
Keyword(s):  
Genetic Characterization ◽  
Immunoglobulin M ◽  
Enzyme Linked Immunosorbent Assay ◽  
Second Phase ◽  
Serum Samples ◽  
Tick Borne Encephalitis ◽  
Specific Immunoglobulin ◽  
Tick Borne Encephalitis Virus ◽  
First Time

Tick-borne encephalitis virus (TBEV) was isolated for the first time in Sweden in 1958 (from ticks and from 1 tick-borne encephalitis [TBE] patient).1 In 2003, Haglund and colleagues reported the isolation and antigenic and genetic characterization of 14 TBEV strains from Swedish patients (samples collected 1991–1994).2 The first serum sample, from which TBEV was isolated, was obtained 2–10 days after onset of disease and found to be negative for anti-TBEV immunoglobulin M (IgM) by enzyme-linked immunosorbent assay (ELISA), whereas TBEV-specific IgM (and TBEV-specific immunoglobulin G/cerebrospinal fluid [IgG/CSF] activity) was demonstrated in later serum samples taken during the second phase of the disease.

Evaluation of management strategy results of laboratory studies in serum samples with hemolysis

2019 ◽  
Vol 1 (4) ◽  
pp. 43-45
Author(s):  
O. A. Klimenkova ◽  
V. P. Pashkova ◽  
T. V. Vavilova ◽  
V. S. Berestovskaya
Keyword(s):  
Management Strategy ◽  
Negative Consequences ◽  
Laboratory Studies ◽  
Serum Samples ◽  
Ongoing Debate ◽  
Clinical Interpretation ◽  
Points Of View ◽  
Test Result ◽  
High Uncertainty

There is an ongoing debate about what the laboratory should do with hemolyzed samples. Several strategies are proposed for managing the results obtained in such samples. The safest option from the analytical and clinical points of view is to perform a study of a new sample without hemolysis. Another approach is to carry out a test irregardless, but at the same time indicate a limit on the clinical interpretation of the result, by making a comment on possible hemoglobin interference. The choice of strategy should be based on a comparison of the risk of negative consequences in the absence of a test result and the likelihood of harm due to the transfer of the result with high uncertainty to the clinician.

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