Search results for "Chain reaction"
showing 10 items of 1862 documents
Natural history of cytomegalovirus infection in a series of patients diagnosed with moderate-severe ulcerative colitis
2011
AIM: To evaluate the natural history of human cytomegalovirus (HCMV) infection in a series of 28 ulcerative colitis patients in whom the search for HCMV was positive. METHODS: A series of 85 patients with moderate-severe ulcerative colitis flare-up were evaluated for a HCMV search by performing a haematoxylin and eosin stain, immunohistochemical assay and nested polymerase chain reaction on rectal biopsies. Among 85 screened patients (19 of whom were steroid resistant/dependant), 28 were positive for HCMV; after remission the patients were followed up clinically and histologically. RESULTS: Among the 22 patients with complete follow-up, in 8 (36%) patients HCMV-DNA persisted in the intestin…
Molecular basis of a new type of C1q-deficiency associated with a non-functional low molecular weight (LMW) C1q: parallels and differences to other k…
1998
Analysis of an abnormal C1q molecule of individuals of a Moroccan family by ultracentrifugation in sucrose gradients revealed a low molecular weight C1q (LMW-C1q). We investigated the molecular basis of this defect by sequencing all six exons of the three C1q genes. One point mutation in the codon for Gly at position 15 (GGT) of the B chain was found resulting in an amino acid substitution to Asp (GAT). The exchange not only leads to an interruption of the collagen-like motif Gly-X-Y, but also introduces one negatively charged residue per B chain which results in two additional charges per structural subunit (A-B, C-C, A-B). The mutation which has been identified by DNA-sequencing in the C1…
Differential association of polymorphisms in the TNFalpha region with psoriatic arthritis but not psoriasis.
2002
To investigate the potential association of tumour necrosis factor alpha (TNFalpha) microsatellite and promoter alleles with psoriatic arthritis (PsA).DNA from 89 white patients with PsA, 65 patients with psoriasis, and 99 healthy white controls was investigated for two TNFalpha promoter (-238 and -308) and three microsatellite polymorphisms (TNFa, c, and d). Patients had previously been studied by serology for HLA class I antigens and by sequence-specific polymerase chain reaction for DRB1* alleles. In addition, TNFalpha production of Ficoll separated peripheral blood mononuclear cells (PBMC) into culture supernatants after stimulation with lipopolysaccharide, alphaCD3 antibodies, phytohae…
Preferential splenic CD8+ T-cell activation in rituximab-nonresponder patients with immune thrombocytopenia
2013
The pathogenic role of B cells in immune thrombocytopenia (ITP) has justified the therapeutic use of anti-CD20 antibodies such as rituximab (RTX). However, 60% of ITP patients do not respond to RTX. To decipher the mechanisms implicated in the failure of RTX, and because the spleen plays a well-recognized role in ITP pathogenesis, 12 spleens from ITP patients who had been nonresponders to RTX therapy were compared with 11 spleens from RTX-untreated ITP patients and 9 controls. We here demonstrate that in RTX-nonresponder ITP patients, preferential Th1 and Tc1 T lymphocyte polarizations occur, associated with an increase in splenic effector memory CD8(+) T-cell frequency. Moreover, in the RT…
Translocation (X;18) in a Biphasic Synovial Sarcoma with Morphologic Features of Neural Differentiation
1998
The authors report a recurred neoplasm showing distinctive histologic, immunophenotypic, and ultrastructural features characteristic of biphasic synovial sarcoma with neural differentiation. The features include areas with a growth pattern of densely packed spindle cells in irregularly intersecting, broad fascicles, diffuse vimentin and HBA 71 immunoreactivity, expression of S-100 protein, and other neural markers. Moreover, areas with glandular structures and cellular expression of cytokeratin and epithelial membrane antigen were noted. Additionally, areas of neural-like growth pattern were positive for neuron-specific enolase, HNK-1, and protein gene product 9.5. Furthermore, cytogenetic …
Third-generation hepatitis C virus tests in asymptomatic anti-HCV-positive blood donors
1994
This study evaluated the performance of third-generation anti-HCV assays in blood donors who were positive by second-generation anti-HCV, and assessed any possible relationship between antibody patterns, HCV replication and liver damage. Fifty-two second-generation enzyme immunoassay-positive asymptomatic Italian blood donors were retested for anti-HCV by third-generation enzyme immunoassay and recombinant immunoblot assay (Ortho third-generation enzyme immunoassay, third-generation recombinant immunoblot assay), utilising recombinant C33c and NS5 and synthetic peptide C100 and C22 antigens, and for HCV-RNA by "nested" polymerase chain reaction with 5' region primers. Alanine aminotransfera…
Diagnostic significance of SARS-CoV-2 IgM positive/IgG negative antibody profile in symptomatic patients with suspected COVID-19 testing negative by …
2020
An outbreak of new coronavirus SARS-CoV-2 was occurred in Wuhan, China and rapidly spread to other cities and nations. The standard diagnostic approach that widely adopted in the clinic is nucleic acid detection by real-time RT-PCR. However, the false-negative rate of the technique is unneglectable and serological methods are urgently warranted. Here, we presented the colloidal gold-based immunochromatographic (ICG) strip targeting viral IgM or IgG antibody and compared it with real-time RT-PCR. The sensitivity of ICG assay with IgM and IgG combinatorial detection in nucleic acid confirmed cases were 11.1%, 92.9% and 96.8% at the early stage (1-7 days after onset), intermediate stage (8-14 …
Quantification of DNA in Plasma by an Automated Real-Time PCR Assay (Cytomegalovirus PCR Kit) for Surveillance of Active Cytomegalovirus Infection an…
2008
ABSTRACT The performance of a plasma real-time PCR (cytomegalovirus [CMV] PCR kit; Abbott Diagnostics) was compared with that of the antigenemia assay for the surveillance of active CMV infection in 42 allogeneic hematopoietic stem cell transplantation (Allo-SCT) recipients. A total of 1,156 samples were analyzed by the two assays. Concordance between the two assays was 82.2%. Plasma DNA levels correlated with the number of pp65-positive cells, particularly prior to the initiation of preemptive therapy. Fifty-seven episodes of active CMV infection were detected in 37 patients: 18 were defined solely by the PCR assay and four were defined on the basis of the antigenemia assay. Either a cutof…
Missing Cases of Herpes Simplex Virus (HSV) Infection of the Central Nervous System When the Reller Criteria Are Applied for HSV PCR Testing: a Multi…
2019
ABSTRACT Previous studies suggested that herpes simplex virus (HSV) PCR testing can be safely deferred in patients with normal cerebrospinal fluid (CSF) white blood cell (WBC) counts and protein levels as long as they are older than 2 years of age and are not immunocompromised, the so-called Reller criteria. In this multicenter study, we retrospectively assessed the validity of these screening criteria in our setting. A total of 4,404 CSF specimens submitted for HSV PCR testing to the respective microbiology laboratories at the participating hospitals between 2012 and 2018 were included. Six commercially available HSV PCR assays were used across the participating centers. Ninety-one of the …
Comparative Evaluation of Three Automated Systems for DNA Extraction in Conjunction with Three Commercially Available Real-Time PCR Assays for Quanti…
2011
ABSTRACT Limited data are available on the performance of different automated extraction platforms and commercially available quantitative real-time PCR (QRT-PCR) methods for the quantitation of cytomegalovirus (CMV) DNA in plasma. We compared the performance characteristics of the Abbott mSample preparation system DNA kit on the m24 SP instrument (Abbott), the High Pure viral nucleic acid kit on the COBAS AmpliPrep system (Roche), and the EZ1 Virus 2.0 kit on the BioRobot EZ1 extraction platform (Qiagen) coupled with the Abbott CMV PCR kit, the LightCycler CMV Quant kit (Roche), and the Q-CMV complete kit (Nanogen), for both plasma specimens from allogeneic stem cell transplant (Allo-SCT) …