Search results for "Laboratory"

Dot-immunobinding assay with the globular domain of collagen type IV for antiglomerular basement membrane antibodies

1988

A dot-immunobinding assay for the detection of antiglomerular basement membrane antibodies has been developed. The globular domain NC1 of basement membrane collagen type IV was used as antigen. The assay proved to be specific, sensitive, and reproducible. Circulating antibodies in each of 12 sera from patients with florid Goodpasture's syndrome could be demonstrated, whereas sera from patients with Goodpasture's syndrome in clinical remission and various control sera showed no reactivity. The advantages of the dot-blot assay are: the usage of the purified Goodpasature target antigen NCI reduces unspecific binding of IgG; only minimal amounts of antigen are required to give a positive signal…

Relationship between the target antigen of liver-kidney microsomal (LKM) autoantibodies and rat isoenzymes of cytochrome P-450

1988

Chronic active hepatitis (CAH) is a clinical syndrome of different etiologies. Liver-kidney microsomal (LKM) autoantibodies characterize a subgroup of HBsAg negative CAH, which is considered to be an autoimmune liver disease. By immunoblotting analysis (IB) LKM positive sera have been shown to react strongly with a poly-peptide band at 50 kD. Therefore we investigated various rat microsomal enzymes with a molecular weight around 50 kD as potential candidate target antigens. These included epoxide hydrolase, cytochrome P-450 reductase, and phenobarbital-inducible isoenzymes of cytochrome P-450 (PB1, PB2, PB3a, PB3b). By radioimmunoassay (RIA) and IB LKM positive sera were shown to react with…

Inter-laboratory evaluation of the ISO standard 11063 "Soil quality - Method to directly extract DNA from soil samples"

2011

International audience; Extracting DNA directly from micro-organisms living in soil is a crucial step for the molecular analysis of soil microbial communities. However, the use of a plethora of different soil DNA extraction protocols, each with its own bias, makes accurate data comparison difficult. To overcome this problem, a method for soil DNA extraction was proposed to the International Organization for Standardization (ISO) in 2006. This method was evaluated by 13 independent European laboratories actively participating in national and international ring tests. The reproducibility of the standardized method for molecular analyses was evaluated by comparing the amount of DNA extracted, …

Leucine aminopeptidase is an immunodominant antigen of Fasciola hepatica excretory and secretory products in human infections.

2007

ABSTRACT The liver fluke Fasciola hepatica parasitizes humans and ruminant livestock worldwide, and it is now being considered a reemerging zoonotic disease, especially in areas in which it is endemic, such as South America. This study investigates the immune response to excretory and secretory products produced by F. hepatica in a group of patients from the Peruvian Altiplano, where the disease is highly endemic. Using a proteomic approach and immunoblotting techniques, we have identified the enzymes leucine aminopeptidase (LAP) and phosphoenolpyruvate carboxykinase as immunodominant antigens recognized by sera from fasciolosis patients. An indirect enzyme-linked immunosorbent assay using …

Análisis de resultados del Programa de Control de Calidad Externo de carga viral del VIH-1, del VHC y del VHB. Año 2013

2015

Human immunodeficiency virus type 1 (HIV-1) and hepatitis B (HBV) and C virus (HCV) viral load determinations are among the most relevant markers for the follow up of patients infected with these viruses. External quality control tools are crucial to ensure the accuracy of results obtained by microbiology laboratories. This article summarized the results obtained from the 2013 SEIMC External Quality Control Programme for HIV-1, HCV, and HBV viral loads. In the HIV-1 program, a total of five standards were sent. One standard consisted in seronegative human plasma, while the remaining four contained plasma from three different viremic patients, in the range of 2-5 log10 copies/mL; two of thes…

Methodology and significance of the detection of liver-kidney-microsomal (lkm) autoantibodies in autoimmune-type chronic active hepatitis

1987

Liver-kidney-microsomal (LKM) autoantibodies are diagnostic markers for a subgroup of HBsAg-negative chronic active hepatitis, presumably owing to autoimmunity. They were originally detected by indirect immunofluorescence and can now be evaluated by radioimmunoassay, enzyme-linked immunosorbent assay, and immunoblotting. In immunoblotting LKM-positive sera react strongly with a 50-kilodalton (KD) polypeptide band of microsomes. In immunoelectron microscopy, LKM-positive sera show a binding with membranes of the endoplasmic reticulum. The LKM antigen was further identified on various isoenzymes of cytochrome P-450. Immunofluorescence is still the method of choice for screening sera routinely…

Significant autoimmune markers of autoimmune liver disorders: Current status

1987

Evaluation of the Architect Epstein-Barr Virus (EBV) Viral Capsid Antigen (VCA) IgG, VCA IgM, and EBV Nuclear Antigen 1 IgG Chemiluminescent Immunoas…

2014

ABSTRACTCommercial immunoassays for detecting IgG and IgM antibodies against Epstein-Barr virus (EBV), viral capsid antigens (VCA), and IgGs toward EBV nuclear antigen-1 (EBNA-1) are routinely used in combination to categorize EBV infection status. In this study, we evaluated the performances of the Architect EBV VCA IgG, VCA IgM, and EBNA-1 IgG chemiluminescent microparticle assays (CMIAs) in EBV serological analyses using indirect immunofluorescence assays and anticomplement immunofluorescence assays as the reference methods for VCA IgG, VCA IgM, and EBNA-1 IgG antibody detection, respectively. A total of 365 serum samples representing different EBV serological profiles were included in t…

Microbiota Variation Across Life Stages of European Field-Caught Anopheles atroparvus and During Laboratory Colonization: New Insights for Malaria Re…

2021

The potential use of bacteria for developing novel vector control approaches has awakened new interests in the study of the microbiota associated with vector species. To set a baseline for future malaria research, a high-throughput sequencing of the bacterial 16S ribosomal gene V3-V4 region was used to profile the microbiota associated with late-instar larvae, newly emerged females, and wild-caught females of a sylvan Anopheles atroparvus population from a former malaria transmission area of Spain. Field-acquired microbiota was then assessed in non-blood-fed laboratory-reared females from the second, sixth, and 10th generations. Diversity analyses revealed that bacterial communities varied …

Validación y verificación analítica de los métodos microbiológicos

2015

Clinical microbiologists should ensure, to the maximum level allowed by the scientific and technical development, the reliability of the results. This implies that, in addition to meeting the technical criteria to ensure their validity, they must be performed with a number of conditions that allows comparable results to be obtained, regardless of the laboratory that performs the test. In this sense, the use of recognized and accepted reference methodsis the most effective tool for these guarantees. The activities related to verification and validation of analytical methods has become very important, as there is continuous development, as well as updating techniques and increasingly complex …