Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Paraffin Embedding”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,801 records · Page 100Linked to original sources
PubMed1996

Detection of Chlamydia in formalin-fixed and paraffin-embedded avian tissue by in situ hybridization. A comparison between in situ hybridization and peroxidase-antiperoxidase labelling.

In situ hybridization, (ISH) using a digoxigenin-antisense RNA-probe to detect chlamydial rRNA was applied to post mortem tissue of birds. The technique was optimized and validated using tissue from experimentally-infected chicken embryos. Tissue sections were also tested by immunohistochemistry (peroxidase-antiperoxidase reaction, PAP) for the presence of chlamydial antigen using a genus specific monoclonal antibody. In the chicken embryo tissue, ISH and PAP were comparably sensitive and specific (100% and 100%, respectively). ISH and PAP in general were correlated to microscopic lesions. For further comparison, ISH with PAP was applied retrospectively to tissues of 82 birds from which Chlamydia had been isolated, or which were suggestive of chlamydiosis. Using in situ hybridization 47 of 82 birds were found to be positive, and as were 23 of 82 birds with PAP. None of the ISH-only positive cases were found to be strongly positive. On the other hand, cases which were found positive with the ISH were also positive with other methods (PAP and isolation of Chlamydiae from chicken embryos). There was no close correlation between the positive cells and histological lesions. In spite of the higher sensitivity and specificity of the ISH, this technique is not suitable for routine diagnostic investigations. ISH is expensive, laborious, and time consuming.

Animals↗
PubMed1984

The influence of various fixatives on the immunohistochemical demonstration of a number of plasma proteins and oncofetal proteins in paraffin embedded material.

The influence of different fixatives on the antigenicity of alpha-fetoprotein (AFP), albumin, prealbumin, transferrin, ferritin, human chorionic gonadotropin (HCG), specific pregnancy beta 1-glycoprotein (SP1) and human placental lactogen (HPL) was studied. No single fixative was superior for all the antigens investigated. For intracellular antigens the best all-around fixatives were, however, 10% buffered formalin, 4% buffered paraformaldehyde, 10% formol-calcium and ethanol acetic acid (EA), cold processed. The preferable fixatives were for AFP: Bouińs fixative, B-5 and EA; for albumin: 10% formol-calcium; for prealbumin: Zambonis fixative and B-5; for transferrin: EA; for ferritin: 10% buffered formalin, 4% buffered paraformaldehyde, Lilliés fixative, Zambonis fixative and EA; for HCG: Bouińs fixative and B-5; for SP1: Lilliés fixative and EA; and for HPL: 4% buffered paraformaldehyde and Lilliés fixative. The preservation of extracellular antigens was different from the above mentioned intracellular ones. Thus fixation in 10% buffered formalin gave poor results while the coagulant fixatives such as Bouińs fixative, B-5 and Clelands fixative in general showed good preservation of the antigenicity of the extracellular antigens.

Antigens, Neoplasm↗
PubMed1981

Immunoperoxidase staining of formalin-fixed, paraffin-embedded, human renal biopsies with a comparison of the peroxidase-antiperoxidase (PAP) and indirect methods.

The results of immunoperoxidase staining of 33 routinely processed renal biopsies correlated with the results of direct immunofluorescence in 79% of tests performed. Most of the discrepant results were due to positive immunoperoxidase staining, possibly reflecting greater sensitivity of the method. A comparison of two immunoperoxidase methods showed that the indirect method produced less intense staining than the peroxidase-antiperoxidase (PAP) method when equivalent primary antibody titres were used. Lowering the primary antibody titres for the indirect technique resulted in equivalent staining by the two methods. Predigestion by protease VII effectively revealed the antigens under study without causing tissue damage or section loss.

Biopsy↗
PubMed2004

Diagnosis of taenia saginata cysticercosis by immunohistochemical test on formalin-fixed and paraffin-embedded bovine lesions.

A new method of diagnosing cysticercus or larval stage of the human tapeworm, Taenia saginata, also known as Cysticercus bovis, in formalin-fixed bovine tissue was developed using a monoclonal antibody to T. saginata and avidin-biotin complex immunohistochemistry. Grossly recognizable viable and degenerate cysts were identifiable after immunohistochemical staining and could be differentiated from Sarcocystis, Actinobacillus, or non-cyst, normal bovine structures. Thenew test should permit laboratory confirmation of suspected T. saginata cysticercus lesions.

Animals↗
PubMed1999

Polymerase chain reaction identification of Mycobacterium avium in formalin-fixed, paraffin-embedded animal tissues.

A PCR procedure previously developed for identification of Mycobacterium bovis in formalin-fixed tissues was used to identify mycobacteria of the M. avium complex. Tissues were examined from 100 culture-positive cases of M. avium complex infection, including 86 in which the subspecies was not identified and 14 that had been identified as M. avium subsp. paratuberculosis. Each sample was tested with 5 primer sets, 16S ribosomal RNA (rRNA), IS900, IS901, IS1245, and a heat shock protein (hspX), that detect 1 or both M. avium subspecies. The success rate of PCR detection varied with the primers used and the animal species tested. Among the 86 cases with no M. avium subspecies designation, primers for the 16S rRNA gene were clearly the most efficient because they produced amplicons from all samples that reacted with any other primer set. The overall detection rate in this group of samples was 71%: highest in avian tissues (89%) followed by swine (72%) and ruminants (57%) None of the avian or swine tissues reacted with primers for IS900 or hspX, which identify M. a. paratuberculosis. In contrast, 7 of the 12 ruminant samples that were 16S rRNA positive reacted with 1 or both of these primers. All of the 14 cases shown by culture to be M. a. paratuberculosis infections were positive with IS900 primers, whereas only 11 were positive for 16S rRNA. These results indicate that 16S rRNA primers are the most useful for PCR identification of M. avium in formalin-fixed tissues of nonruminant species. However, IS900 primers should also be used when ruminant tissues are examined because these primers provide the greatest sensitivity for detection of M. a. paratuberculosis infections.

Animals↗
PubMed2002

Immunohistochemical detection of Yersinia pestis in formalin-fixed, paraffin-embedded tissue.

Yersinia pestis infection usually is limited to lymph nodes (bubo); rarely, if bacteria are aerosolized, pneumonic plague occurs. We developed an immunohistochemical assay using a monoclonal anti-fraction 1 Y pestis antibody for formalin-fixed tissues. We studied 6 cases using this technique. Respiratory symptoms were prominent in 2 cases; histologically, one showed intra-alveolar inflammation, and the other had alveolar hemorrhage and edema. By using the immunohistochemical assay, we found intact Yersinia and granular bacterial antigen staining in alveoli, bronchi, and blood vessels. Of the remaining cases, 2 had septicemia and 2 had a bubo. Pathologic changes included lymphocyte depletion, necrosis, edema, and foamy macrophages in lymph nodes; multiple abscesses in the spleen; fibrin thrombi in glomeruli; and unremarkable lungs. By using the immunohistochemical assay, we identified intact bacteria inside monocytes and granular antigen staining in blood vessels. The immunohistochemical assay provided a fast, nonhazardous method for diagnosing plague. The immunohistochemical assay localizes bacteria, retaining tissue morphologic features, and can help define transmission mechanisms.

Adolescent↗

Refine your search to explore more results.