SEARCH · Search PubMed

Results for “Tissue 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.

SourceResearch connectionFrom yearThrough year

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

At least 559 records · Page 31Linked to original sources

PubMed1989

Warthin's tumor with malignant lymphoma. DNA analysis of paraffin-embedded tissue.

The authors report a case of malignant lymphoma, small lymphocytic type, involving the lymphoid stroma of a Warthin's tumor of the parotid gland. This was confirmed by the presence of a monoclonal immunoglobulin heavy chain gene rearrangement, demonstrated by Southern blot hybridization of DNA extracted from paraffin-embedded tissue. Similar techniques showed only germline immunoglobulin gene bands in two control cases of Warthin's tumor.

Adenolymphoma↗

PubMed2004

Use of paraffin-embedded tissue for identification of Saccharomyces cerevisiae in a baker's lung nodule by fungal PCR and nucleotide sequencing.

A 40-year-old healthy male employed in a bakery presented with a single lung nodule and underwent investigations to rule out pulmonary carcinoma. Biopsy was positive for yeast cells, which did not match common fungal pathogens. PCR assay of paraffin-embedded tissue and nucleotide sequencing with ribosomal ITS1-ITS2 universal primers revealed the presence of Saccharomyces cerevisiae.

Adult↗

PubMed2005

Amplification and sequencing of Brachyspira spp. specific portions of nox using paraffin-embedded tissue samples from clinical colitis in Austrian pigs shows frequent solitary presence of Brachyspiramurdochii.

Brachyspira infections are significant causes of enterocolitis in pigs. In order to differentiate pathogenic species (Brachyspira (Br.) hyodysenteriae, Brachyspira pilosicoli) from less pathogenic or non-pathogenic species (Brachyspira intermedia, Brachyspira innocens, Brachyspira murdochii) in paraffin-embedded tissue samples a polymerase chain reaction (PCR) protocol allowing identification of Brachyspira at species level in archival material was developed. This approach was complemented by sequencing of the PCR amplification products. All seven cases presented with clinical and morphological Brachyspira-associated enterocolitis. Br. hyodysenteriae was not identified in any of the cases, while Br. pilosicoli was identified in a single case in conjunction with Br. murdochii. One case each was found positive for Br. innocens and Br. intermedia. Interestingly, the majority of cases presented as single or double infections with Br. murdochii. In some of the pigs other pathogens, like porcine circovirus-2 or Lawsonia intracellularis were present. These observations point at the possibility that under certain conditions even Brachyspira species of low pathogenicity can multiplicate extensively and lead to Brachyspira-associated enterocolitis.

Animals↗

PubMed1989

Detection of cytomegalovirus infection in paraffin-embedded tissue specimens with the polymerase chain reaction.

The polymerase chain reaction (PCR) is a recently developed method whereby a specific DNA sequence in a complex mixture can be selectively amplified and visualized by ethidium bromide staining after electrophoresis. We have been able to perform PCR on DNA purified from paraffin-embedded tissues, as well as on crude DNA obtained by directly boiling deparaffinized thick sections. With the use of appropriate priming oligonucleotides, the presence of cytomegalovirus DNA in infected tissues can be detected with sensitivity and specificity in as short as 6 h, without the use of radioisotopes. Therefore, PCR may be a viable adjunct to culture techniques for detection of viral diseases, particularly in cases where fresh tissue is not available for analysis.

Base Sequence↗

PubMed1989

Epithelial markers in synovial sarcoma. An immunohistochemical study on paraffin embedded tissues.

Immunohistochemical studies on synovial sarcomas have proved the potentiality of these neoplasm for epithelial and mesenchymal differentiation and antibodies detecting epithelial cells have been found to be helpful in determining the histological types. In this study different epithelial markers directed against various cytokeratins, HMFG-2 and EMA were investigated on paraffin embedded tissues of 13 cases of synovial sarcomas, with regard to their reliability in unmasking the epithelial components demonstrable in this type of neoplasm. The results lead to three conclusions: firstly, synovial sarcomas possess the capacity for generating different epithelial cell types with uncommon compositions of intermediate filaments as well as of membrane proteins, secondly, these features may be expressed in a heterogenous pattern even within the same tumour and finally, the use of wide range anti-cytokeratin antibodies covering the spectrum of basic as well as acidic type proteins seems to be necessary for the detection of all epithelial components demonstrable in synovial sarcomas.

Antibodies↗

PubMed1989

Identification of cryptosporidium in paraffin-embedded tissue sections with the use of a monoclonal antibody.

Recently a monoclonal antibody has been developed against the oocyst form of Cryptosporidium species for use in detecting the organism in fecal material. The authors undertook this study to determine if this antibody could be used in identifying Cryptosporidium species in paraffin-embedded tissue sections. Three biopsies showing Cryptosporidiosis as diagnosed by characteristic appearance by light and electron microscopy were selected from the surgical pathology files at the authors' institution. Paraffin sections were examined with the use of both an indirect immunofluorescence and an avidin-biotin-peroxidase technique. In all the cases, prominent staining of oocysts was seen; however, intracellular trophozoites did not react with the antibody. The authors conclude that this antibody can be used to identify Cryptosporidium species oocysts in tissue sections and that the antibody appears to be specific for the oocyst form only.

Adult↗

PubMed1988

Application of a monoclonal antibody for the detection of Trichosporon beigelii in paraffin-embedded tissue sections.

Trichosporon beigelii is a normal inhabitant of soil and is occasionally found as normal flora of the skin and mouth. Opportunistic infection by this fungus has been increasingly reported in immunocompromised patients. The diagnosis of this infection depends on positive cultures or histological evidence. However, it is sometimes difficult to distinguish this fungus from Candida species in tissue section. We have generated two monoclonal antibodies that can distinguish T. beigelii from other fungi including several species of Candida. One of these antibodies (K-16) reacts with T. beigelii in formalin-fixed, paraffin-embedded tissue sections and will be useful as an aid to the accurate diagnosis of trichosporonosis.

Antibodies, Fungal↗

PubMed1987

Retention, localization and staining of lipids in tissues embedded in water-miscible methacrylates: using the solubility parameter to analyse the influences of resins, plasticizers, and other reagents.

The influences of a wide variety of technical factors (the nature of the monomer and plasticizer, the duration and temperatures of the processing steps, etc.) on retention, localization and staining of lipid in tissues embedded in water-miscible methacrylates were assessed experimentally. This analysis was aided by the use of the solubility parameters of the substances as quantitative indicators of miscibility. The technical requirements for, and limits of, lipid histochemistry using resin sections have therefore been established on a quantitative basis.

Acrylates↗

PubMed1996

In situ hybridization for vasopressin mRNA in the human supraoptic and paraventricular nucleus; quantitative aspects of formalin-fixed paraffin-embedded tissue sections as compared to cryostat sections.

In order to study the suitability of formalin-fixed paraffin-embedded brain tissue for vasopressin (AVP)-mRNA detection, we used symmetric halves of 5 human hypothalami. In every case, one half was formalin fixed for 10-35 days and paraffin embedded while the other half was frozen rapidly. Following in situ hybridization (ISH) histochemistry on systematically obtained sections of the supraoptic (SON) and paraventricular nucleus (PVN) of both halves, total amounts of AVP-mRNA in these nuclei were estimated using densitometry of film autoradiographs. Total amounts of radioactivity were found to vary considerably between patients and amounted to 1297 +/- 302 arbitrary units (AU) (PVN) (mean +/- SEM) and 2539 +/- 346 (SON) for the cryostat sections and 868 +/- 94 (PVN) and 1259 +/- 126 (SON) for the paraffin tissue. Variations introduced by the method itself yielded a coefficient of variation of only 0.19. Furthermore, a non-significant negative trend with postmortem delay was found in cryostat tissue, but not in paraffin sections. No effect of fixation time was observed in the paraffin tissue. Both ways of tissue treatment have specific advantages and disadvantages that may be different for other probes or other brain areas. For ISH of a highly abundant mRNA like AVP in a very heterogeneous brain area such as the human hypothalamus, formalin-fixed paraffin-embedded tissue sections can be used for quantitative analysis of entire brain nuclei because of the small variation in this tissue, the remarkably good signal recovery (some 75% as compared to cryostat sections) and its practical advantages with regards to anatomical orientation, storage and sampling of the tissue.

Fixatives↗

PubMed1994

Detection of T-cell clonality in paraffin-embedded tissues.

In lymph node diagnosis, difficulties are frequently encountered with the differential diagnosis of reactive and neoplastic T-cell proliferations. Immunohistochemistry is of limited use, and fresh frozen material for DNA studies is not available in many cases. We have established a polymerase chain reaction (PCR) technique to amplify rearranged T-cell receptor (TCR)-gamma sequences from paraffin-embedded material. Our method differs from other techniques previously described in that it uses four sets of family-specific variable (V)gamma primers. Clonality of the investigated T cells is reflected not only by the varying lengths of amplified products but also by differences in the relative amount of rearranged V gamma families. Preliminary studies indicate that this approach can provide information about the presence of predominant T-cell clones within the sample and thus help to classify the lymph node lesion. With this technique we were able to confirm clonality in seven of 12 T-cell lymphomas in paraffin-embedded tissues.

Adult↗

PubMed1999

Immunohistochemical detection of hog cholera virus antigen in paraffin wax-embedded tissues from naturally infected pigs.

In 17 pigs submitted for diagnosis in 1980, hog cholera was confirmed by viral isolation, by a direct immunofluorescent antibody test for viral antigen, and by the presence of characteristic histopathological lesions. In the present study, hog cholera viral antigen was demonstrated in these pigs by immunohistochemical examination of formalin-fixed paraffin wax-embedded tissues that had been stored for 18 years. Viral antigen was detected in crypt epithelial cells of the tonsil, collecting tubular epithelial cells of the kidney, bronchial and bronchiolar mucosal and gland cells of the lung, and pancreatic epithelial cells.

Animals↗

PubMed1998

New monoclonal antibodies to the T cell antigens CD4 and CD8. Production and characterization in formalin-fixed paraffin-embedded tissue.

We have generated a recombinant protein representing part of the CD4 molecule and a peptide representing an epitope of predicted high antigenicity on the CD8 molecule and employed these to generate mouse monoclonal antibodies using standard hybridoma protocols. The extracellular domain of the CD4 molecule was obtained by reverse transcription of mRNA from peripheral blood lymphocytes followed by polymerase chain reaction. The amplified gene fragment was cloned into an expression vector to allow a histidine-tagged fusion protein to be produced in Escherichia coli. Purified fusion protein was used to immunize mice. The CD8 monoclonal antibody was raised against a peptide consisting of 13 amino acids within the carboxyl-terminal region of the CD8 cytoplasmic domain. The antibodies showed appropriate reactivity on Western blotting. By heat pretreatment, these antibodies have been shown to be highly effective on paraffin-embedded tissue. In normal lymphoid tissue, the expected distribution of CD4 and CD8 lymphocytes was observed. In a series of 16 T cell lymphomas and B cell lymphomas, immunostaining results were compared with those obtained using reagents effective only in frozen tissue. A high degree of correlation was observed. These results suggest that NCL-CD4 and NCL-CD8 may be of value in the characterization of T cell disorders.

Antibodies, Monoclonal↗

PubMed2005

p53 alterations in sequential biopsies of Asian follicular lymphoma: a study of immunohistochemical staining pattern and gene mutations by PCR-SSCP in paraffin-embedded tissues.

AIM: Tumour suppressor gene p53 is a common target in carcinogenesis, reported to be altered and functionally inactive in 70% of human cancers. Although p53 mutations are less commonly present in haematological malignancies when compared with other solid tumours, they have been reported in histological transformation of follicular lymphoma. We aimed to investigate the frequency of p53 gene alterations in paraffin-embedded tissue using commercially available PCR-SSCP, and to correlate the results with P53 protein expression by immunohistochemistry. METHODS: Surgical samples from seven patients with a total of 17 sequential biopsies were retrieved for the study of p53 gene expression using immunohistochemical stain, and gene status by PCR-SSCP for exons 5-8. The tumours were graded according to the WHO classification criteria. P53 was distinctly over-expressed in five transformed higher grade biopsies, and all except one showed electrophoretic mobility shift in PCR-SSCP analysis. Sequencing analysis revealed single nucleotide substitutions in three of four of these high-grade transformed cases with band shift (75%), whereas some other studies reported a lower frequency of 25-30%, and mobility shift result was found to correlate with P53 expression. Lower grade tumours without P53 over-expression did not demonstrate band shift, and sequencing analysis did not reveal mutations. CONCLUSIONS: We demonstrated the feasibility of adopting PCR-SSCP for screening of p53 mutations in archival tissue samples in this study, and there is a strong correlation of p53 gene over-expression and mutation events in high-grade transformed tumours.

Adult↗

PubMed2006

Improved RT-PCR amplification for molecular analyses with long-term preserved formalin-fixed, paraffin-embedded tissue specimens.

Recently, in addition to DNA, RNA extracted from archival tissue specimens has become an invaluable source of material for molecular biological analysis. Successful amplification with PCR/RT-PCR is problematic when using amplicons of short size due to degradation of DNA or RNA. We established an improved method for efficient RT-PCR amplification of RNA extracted from archival formalin-fixed, paraffin-embedded tissue by the elimination of RNA modification and the restoration of RNA template activity. Namely, the preheating in citrate buffer (pH 4.0) of RNA extracted from long-term preserved tissue specimens resulted in significantly increased efficiency of RT-PCR.

Buffers↗

PubMed1994

Expression of EGF, EGF-receptor, p53, v-erb B and ras p21 in colorectal neoplasms by immunostaining paraffin-embedded tissues.

Immunohistochemical studies were performed to clarify the significance of the expression or overexpression of epidermal growth factor (EGF), EGF-receptor (EGFR), p53, v-erb B, ras p21 in 23 cases each of tubular adenoma and adenocarcinoma. The expression of EGF, EGFR, p53, v-erb B, and ras p21 in paraffin-embedded tissues, from 46 patients with colorectal tumors (adenoma: 23 cases; 14 mild dysplasia, six moderate dysplasia, three severe dysplasia, adenocarcinoma: 23 cases; 17 well differentiated, two moderately differentiated, three poorly differentiated, one mucinous carcinoma was analyzed immunohistochemically using anti-EGF, EGFR, p53, v-erb B and ras p21 antibodies. The EGF and ras p21 tended to express more strongly in carcinoma cases than in the adenoma cases, and in severe and moderate dysplasia than in mild dysplasia (EGF: stained positive in five adenomas [21.74%] and 17 adenocarcinomas [73.91%]; ras p21: stained positive in six adenomas [26.09%] and 14 adenocarcinomas [60.87%]. The EGFR stained positive in two adenomas (8.70%) and two adenocarcinomas (8.70%). The p53 and v-erb B showed positive staining only in the carcinoma cases (p53: stained positive in four cases [17.39%]; v-erb B: stained positive in eight cases [34.78%]). This study suggests that these factors seem to have some role in the progression of colon neoplasms. It suggests that genetic alteration is not always equal to the overexpression of protein products, but that it reflects them well, and that the staining makes some contribution to differential diagnosis in colorectal neoplasms.

Adenocarcinoma↗

PubMed1990

Demonstration of Epstein-Barr virus in primary brain lymphoma by in situ DNA hybridisation in paraffin wax embedded tissue.

Tumour tissue from 29 patients with primary brain lymphoma was reviewed to determine if there was an aetiological association between Epstein-Barr virus and polyclonal and monoclonal lymphoproliferations. The morphology and immunophenotype in 24 patients for whom paraffin wax embedded tissue was available were studied. A high grade pleomorphic tumour morphology with plasmacytoid features was seen in 13 tumours. Because of the large number of pleomorphic lymphomas, all tumours were examined for the presence of the Epstein-Barr virus genome using in situ DNA hybridisation. A panel of three biotinylated probes to different sequences in the Epstein-Barr virus genome was used. Positive hybridisation with one or more probes was shown in tumours from 11 patients. The remaining tumours gave no hybridisation signal. There was no correlation between positive hybridisation and morphological subtype or clinical outcome.

Adolescent↗

PubMedDate not supplied

Anti-BLA.36 monoclonal antibody shows reactivity with Hodgkin's cells and B lymphocytes in frozen and paraffin-embedded tissues.

A newly developed monoclonal antibody, anti-BLA.36, raised against a Hodgkin cell line, was shown to have reactivity with Reed-Sternberg cells and activated B lymphocytes and appears to be distinct from other antibodies which identify antigens of hematopoietic cells. Anti-BLA.36 was evaluated in B5-fixed paraffin-embedded tissue from 16 cases of Hodgkin's disease of various types and 35 cases of non-Hodgkin's lymphomas representative of the different major subtypes. The specificity of anti-BLA.36 was compared with other antibodies that have been used to mark Hodgkin's cells and B lymphocytes: namely, L26, LN-1, Leu-M1 and Ber-H2, as well as UCHL-1, a pan-T lymphocyte marker. In addition, a subset of the cases was evaluated using frozen tissue in order to validate the staining characteristics of anti-BLA.36 as observed in fixed paraffin sections. Anti-BLA.36 was found to react with Hodgkin's cells more consistently than the other antibodies used in this panel. The antibody reacted with an antigen on Reed-Sternberg cells and their variants (Hodgkin's cells) in all four subtypes of Hodgkin's disease, and with a subset of reactive and malignant B lymphocytes, but not with T lymphocytes. It may, therefore, be useful in the evaluation of non-Hodgkin's lymphomas. Finally, this is the first antibody raised to a Hodgkin's cell line which also consistently marks reactive and malignant B cells, but not T cells. The implications of this observation are discussed in relation to the cellular origin of the Reed-Sternberg cell and the overall nature of Hodgkin's disease.

Antibodies, Monoclonal↗

PubMed1997

Detection of equine and bovine T- and B-lymphocytes in formalin-fixed paraffin-embedded tissues.

Formalin-fixed paraffin-embedded sections of equine and bovine lymph nodes, spleen, thymus, and Peyer's patches were incubated with monoclonal antibodies to B-lymphocyte markers BLA.36, B29, and mb-1 and T-lymphocyte markers CD3 and CD5. The monoclonal antibody BLA.36 reacted with 80-90% of lymphocytes in the germinal centers and mantle zones of follicles in lymph nodes, spleen, and Peyer's patches. In addition, 90% of lymphocytes in the marginal zone of the spleen, and variable numbers of lymphocytes within lymph node medullary cords were immunopositive for BLA.36. Antibodies to B29 and mb-1 produced similar staining patterns as BLA.36 with fewer positive cells in the germinal centers and medullary cords. BLA.36, B29, and mb-1 reacted with 30-50% of lymphocytes in the medulla of the thymus and with 5-10% of lymphocytes in the cortex. CD3 and CD5 reacted with 90% of lymphocytes in the paracortex and parafollicular zones of lymph nodes, spleen, and Peyer's patches; 40-50% of lymphocytes in the medullary cords of lymph nodes, and scattered positive cells within follicles. Anti-CD3 antibody reacted with 95% of lymphocytes in the splenic red pulp, but antibodies directed against CD5 reacted only faintly with approximately 5-10% of lymphocytes in the red pulp. CD3 and CD5 reacted with 50-60% of cells in the medulla of the thymus and with 40-80% of lymphocytes in the thymic cortex. The biochemical characterization of the antibodies by Western blotting against lysates of equine and bovine peripheral blood mononuclear cells confirmed that antibodies to BLA.36, mb-1, B29, CD3, and CD5 detected molecules of the same approximate molecular mass as found on lymphoid cells of human beings and rats.

Animals↗