SEARCH · PubMed Health

Results for “Paraffin Embedding”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 1,153 records · Page 64Linked to original sources

PubMed1983

Free radical signal of bile pigment in paraffin embedded liver tissue.

A linear correlation have been found between the amplitude of the free radical signal of the electron spin resonance (ESR) spectrum of paraffin embedded liver blocks and the number of bile casts in the histological sections made from these blocks. It has been suggested that the major part of the ESR free radical signal arises from bile pigment, but the contribution of "age pigment" cannot be excluded. On the basis of model experiments the majority of these radical centers was assigned to protein bound bilirubin. In the course of histological processing more than 80% of various free radical centers arising in air dried liver tissue is extracted.

Bile↗

PubMed1986

Human and viral gene detection in routine paraffin embedded tissue by in situ hybridisation with biotinylated probes: viral localisation in herpes encephalitis.

A simple reproducible protocol for detecting multiple copy human genes and viral DNA in routine formalin fixed paraffin embedded tonsil and brain, by in situ hybridisation with biotinylated probes, is described. The protocol consists of digestion of formalin fixed paraffin sections, with 0.4% pepsin in 0.01 M hydrochloric acid for one hour at 37 degrees C, followed by hybridisation with biotinylated probes. The biotinylated probes used for establishing the conditions for in situ localisation of DNA were total placental DNA (TG1), pHY 2.1 (a Y chromosome probe), and herpes simplex virus I and II. In human male tonsil TG1 labelled all nuclei and pHY 2.1 reacted only with nuclear Y bodies. In herpes encephalitis the virus was detected in some glial cells and neurones.

Biotin↗

PubMed1988

How reproducible are flow cytometry data from paraffin-embedded blocks?

The purpose of this technical report is to determine the reproducibility of flow cytometry data for ploidy and cell cycle kinetics using paraffin-embedded blocks of breast cancer tissue. One block from each of 39 tumors was studied in this report with each block having multiple sections analyzed independently. All of these sections gave ploidy analyses, while only 34 gave cell kinetic values. The standard deviation for the DNA index value in the multiple analysis study was less than 0.1 in all but three cases. The cell kinetic values gave larger variability, and the actual values were dependent on the method of analysis. Comparison of the variability for each method of analysis could not predict which procedure was superior. These results would indicate that ploidy is a reproducible value, while cell kinetic parameters should only be used as an indicator of proliferative activity that has been normalized to the mean or median of a large set of observations processed and analyzed by the same procedure.

Breast Neoplasms↗

PubMed1994

Preferential localization of c-kit product in tissue mast cells, basal cells of skin, epithelial cells of breast, small cell lung carcinoma and seminoma/dysgerminoma in human: immunohistochemical study on formalin-fixed, paraffin-embedded tissues.

Eighteen hundred and eighty-four cases of human solid tumours and 833 samples of normal human tissues, formalin-fixed and paraffin-embedded, were examined immunohistochemically for expression of c-kit oncogene product using polyclonal antibody against synthesized c-kit peptide. Seminoma/dysgerminoma and small cell lung carcinoma (SCLC) show preferential c-kit expression at 92% and 36% frequency, respectively, whereas only sporadic cases of cervical carcinoma and non-SCLC lung carcinoma show c-kit positivity. A normal tissue counterpart positive for c-kit product is detected in the testis (spermatocyte) and ovary (oocyte) but not in the lung or the cervix. In contrast, normal epithelial cells of the breast, skin basal cells and tissue mast cells harbour c-kit product, but transformed cells of the former two are largely deficient in the c-kit protein. One hundred and thirty-nine neuroendocrine tumours and 39 non-pulmonary small cell carcinomas were all negative, except for two cases of neuroblastoma. This indicates a distinct character for SCLC in c-kit expression. The c-kit product may be a useful marker in diagnostic pathology of seminoma/dysgerminoma and SCLC among human solid tumours, and in distinction of SCLC from non-pulmonary small cell carcinoma.

Adult↗

PubMed1978

Identification of Rickettsia rickettsii in formalin-fixed, paraffin-embedded tissues by immunofluorescence.

With slight modification of a trypsin digestion technique, Rickettsia rickettsii were demonstrated specifically by immunofluorescence staining in Formalin-fixed, paraffin-embedded tissue sections from a human, rhesus monkey, and guinea pig with Rocky Mountain spotted fever and in infected membranes from a chicken embryo. Tissues were cut at 4 micron and, using geltain as a tissue adhesive, were hydrated in a routine manner. Sections were then digested in refrigerated 0.1% trypsin for 16 h, washed, and stained specifically for R. rickettsii by direct or indirect immunofluorescence. Rickettsial organisms were localized in affected vessels of the mammalian species and within the yolk sac epithelium of the chicken embryo. Specificity was confirmed by adsorbing antibody conjugates with R. rickettsii organisms. Trypsin digestion probably decreased tissue proteins which interfered with immunochemical attachment of antibody to the rickettsiae. The technique is valuable in that a diagnosis of Rocky Mountain spotted fever can be confirmed from Formalin-fixed tissues processed in a routine manner.

Animals↗

PubMed1993

Update on proliferation-associated antibodies applicable to formalin-fixed paraffin-embedded tissue and their clinical applications.

This review provides an update on proliferation-associated antibodies applicable to immunohistochemical techniques in formalin-fixed paraffin-embedded tissue. New insights into proliferating cell nuclear antigen (PCNA) and antibodies to PCNA are presented. The characterization of the protein recognized by the Ki-67 antibody has enabled production of a new range of antibodies (monoclonal and polyclonal) which have immunostaining profiles similar to those of the original antibody. A new proliferation-associated antibody, KiS1, is described. The clinical applications of antibodies to PCNA in human material are summarized, and the limitations of these studies are discussed.

Animals↗

PubMed1996

Immunoreactivity of new antibodies anti-p53 and anti-MDM-2 in paraffin embedded tissue samples.

Detection of various epitopes of the p53 and MDM-2 proteins, using new antibodies was performed on formalin-fixed and paraffin-embedded tissue samples from breast cancer and compared with results obtained using well-characterized antibodies. The results show that the distribution of positive nuclei and intensity of staining varies significantly depending on the antibody used, as well as on the microwaving procedure. Antibodies DO-14, DO-13 and SMP-14 have very good characteristics and are available for immunohistochemical analysis of p53 and MDM-2. Our results indicate, that immunohistochemical expression of p53 and MDM-2 is a not stable and unitary phenomenon and from this point of view a single antibody is not sufficient for its determination. Since, characteristics of p53 and MDM-2 molecules can vary from one sample to the next, panel antibodies capable of determining a wide range of wide type and mutant conformations must be used.

Antibodies↗

PubMed1993

Immunohistochemical detection of strain-specific major histocompatibility complex class I antigens in paraffin-embedded rat osteochondral tissue.

An immunohistochemical method using formalin-fixed, paraffin wax-embedded sections is described for detecting strain-specific major histocompatibility complex class I antigens in knee-joint tissue from DA and Lewis strains of rat. The fixed osteochondral tissues were additionally decalcified in formic acid before processing for paraffin wax embedding. For immunohistochemistry, two monoclonal antibodies, one specific for DA class I allele RT1Aa and the other for Lewis class I allele RT1A1, were used together with the avidin-biotin immunoperoxidase procedure. It was necessary to use strain-specific normal rat serum as a diluent for the antibodies to suppress cross-strain recognition. DA-specific antibody stained positively only on DA rat sections, not on Lewis rat sections, and Lewis-specific antibody stained positively only on Lewis rat sections, and not on DA. Positive staining was localized in the bone marrow, osteochondral cells and endothelium. We propose that the use of a decalcification medium may have enhanced the immunoreactivity of the tissue. The method described can be used on sections of allografts from the two strains of rat to assess morphologically the extent of cellular replacement of the graft by the host's cells.

Animals↗

PubMed1987

Detection of cytomegalovirus infection by means of DNA isolated from paraffin-embedded tissues and dot hybridization.

A specific and rapid method for detecting the presence of cytomegalovirus (CMV) DNA in formalin- or mercuric chloride-fixed, paraffin-embedded tissue has been developed. With dot hybridization with a biotinylated CMV DNA probe, the presence of CMV infection can be readily detected even if only a minority of the cells in the tissue block are infected. The sensitivity is further increased by about two orders of magnitude if high specific-activity 32P-labeled probe is used. This method of detection is more sensitive than histologic diagnosis, appears to be roughly comparable to that by virus isolation in culture, and should be applicable to the detection of other infectious agents.

Autopsy↗

PubMed1985

Influence of fixation and decalcification on the immunohistochemical staining of cell-specific markers in paraffin-embedded human bone biopsies.

A number of fixation and decalcification procedures were evaluated to determine their suitability for immunohistochemistry on trephine samples of bone marrow after paraffin embedding. In particular, the immunoreactivity of antigens characteristic for various hematopoietic cell lines (immunoglobulin heavy and light chains for plasmacytoid cells; elastase for neutrophil myeloid cells; lysozyme, alpha-1-antitrypsin and alpha-1-antichymotrypsin for hystiocytic cells; leukocyte common antigen for lymphocytes; hemoglobin and glycophorin A for erythroid cells; Factor VIII-related antigen for thrombocytoid cells) as well as some antigens specific for epithelial tumors (CEA, 115D8, and keratin) were investigated. Fixation in a mercuric chloride-formaldehyde mixture followed by decalcification in acetic acid-formaldehyde-saline proved to be the best procedure for antigen preservation and retention of morphologic detail. Moreover, there is no need of trypsinization when using this procedure. The only exception was Factor VIII-related antigen in megakaryocytes, which was best demonstrated in trypsin-digested sections of formalin-fixed and acetic acid-decalcified biopsies.

Antigens↗

PubMed1983

Method for analysis of cellular DNA content of paraffin-embedded pathological material using flow cytometry.

A method has been developed that allows flow cytometry to be used for measuring the cellular DNA content of paraffin-embedded human tumors. Thick (i.e., 30 micron) sections were cut from tissue blocks using a microtome and dewaxed in xylene. The sections were then rehydrated by sequentially immersing them in 100, 95, 70, and 50% ethanol before finally washing in distilled water. Single cell suspensions were then prepared by incubation in 0.5% pepsin, pH 1.5, at 37 degrees C for 30 min. The cells were counted, washed, and stained with 1 microgram/ml 4',6'-diamidino-2-phenylindole for 30 min, and DNA content was measured using an ICP 22 flow cytometer. There was a good correlation between the DNA histograms produced using this method and those obtained using unfixed tissue from the same tumor stained with ethidium bromide plus mithramycin. This method allows the retrospective study of archival material where the clinical outcome is already known, and it should, therefore, be particularly useful for determining the prognostic significance of abnormal DNA content measured by flow cytometry.

DNA, Neoplasm↗

PubMed1990

The AMeX method: a multipurpose tissue-processing and paraffin-embedding method. II. Extraction of spooled DNA and its application to Southern blot hybridization analysis.

In our previous report, we described a new fixation and paraffin-embedding method (the AMeX method) that preserves many of the antigens that are normally destroyed by routine formalin fixation. The current study was conducted to examine the preservation of high-molecular-weight DNA in tissues processed by this method. DNA was extracted from AMeX-processed tissue sections after deparaffinization by the same method as that used to extract DNA from fresh tissues. The total amounts of DNA extracted from 10 mg each in wet weight of AMeX-processed and fresh mouse liver tissues were identical. In tissues of malignant lymphoma, the total amount of spooled DNA extracted from 50 sections, each 20 microns thick, was about 8 micrograms/mm2. The electrophoretic pattern of DNA digested with restriction endonucleases on agarose gel from AMeX-processed tissue sections did not differ from that of fresh materials. Southern blot hybridization analysis also revealed that the mobility of specific DNA fragments was identical for AMeX-processed and fresh tissues. The AMeX method was thus proved to be a versatile multipurpose tissue-processing procedure, which is expected to provide important information regarding the correlation between morphology, phenotypic expression, and gene alteration.

Blotting, Southern↗

PubMed2004

Microdissected region-specific gene expression analysis with methacarn-fixed, paraffin-embedded tissues by real-time RT-PCR.

We have previously shown methacarn to be a versatile fixative for analysis of proteins, DNA, and RNA in paraffin-embedded tissues (PETs). In this study we analyzed its suitability for quantitative mRNA expression analysis of microdissected PET specimens using a real-time RT-PCR technique. Fidelity of expression in the methacarn-fixed PET sections, with reference to dose-dependent induction of cytochrome P450 2B1 in the phenobarbital-treated rat liver, was high in comparison with the unfixed frozen tissue case, even after hematoxylin staining. RNA yield from methacarn-fixed PET sections was equivalent to that in unfixed cryosections and was also not significantly affected by hematoxylin staining. Correlations between the expression levels of target genes and input amounts of extracted RNA in the range of 1-1000 pg were very high (correlation coefficients >0.98), the regression curves being similar to those with unfixed cryosections. Although cell numbers should be optimized for each target gene/tissue, >/=200 cells were necessary for accurate measurement in 10-microm-thick rat liver sections judging from the variation of measured value in small microdissected areas. These results indicate high performance with methacarn, close to that of unfixed tissues, regarding quantitative expression analysis of mRNAs in microdissected PET-specimens.

Acetic Acid↗

PubMed1999

The detection of CD2+, CD4+, CD8+, and WC1+ T lymphocytes, B cells and macrophages in fixed and paraffin embedded bovine tissue using a range of antigen recovery and signal amplification techniques.

In order to develop procedures to label the main bovine leucocyte populations in paraffin embedded sections, the immunoreactivity of 25 monoclonal antibodies (mAbs) to different leucocyte antigens was assessed with formal dichromate (FD5) and 10% formalin fixation, a battery of antigen retrieval (AR) methods, and the biotin-tyramide amplification system. All the leucocyte populations investigated (CD2+, CD4+, CD8+, WC1+ T lymphocytes, B cells and macrophages) were strongly and specifically detectable under an appropriate combination of mAb, AR method and signal amplification system. CD4 and CD8 required the most stringent conditions and could only be demonstrated in FD5 fixed sections. For detection of CD2, WC1+ T lymphocytes, B cells and macrophages, all the mAbs produced immunoreactivity in FD5 or formalin fixed tissues. The need to check a range of different AR methods is stressed, as the method of choice varied for each individual mAb. The incorporation of the signal amplification system was necessary to observe a strong signal and the complete distribution of CD4, CD8 and B cells. Fixation by FD5 proved to be better than formalin for the preservation of surface antigens but it was inferior for the detection of markers which were found to show cytoplasmic immunoreactivity, such as the macrophage marker MAC387 or the B cell markers BAQ155 or IL-A59.

Animals↗

PubMed1996

Comprehensive study of several general and type-specific primer pairs for detection of human papillomavirus DNA by PCR in paraffin-embedded cervical carcinomas.

We have compared the efficacies of three general primer pairs for the detection of human papillomavirus (HPV) DNA in formaldehyde-fixed paraffin-embedded carcinomas. The use of these primer pairs leads to underestimates of the HPV prevalence (GP5/6, 61.1%; CPI/IIG, 57.4%; MY09/11, 46.9%; combined, 72.8%). The efficacy of each primer pair seemed to be inversely correlated to the length of the amplimer produced. By using newly developed type-specific primer pairs (amplimer length, approximately 100 bp), an increase in HPV DNA detection (87.6%) was found.

Base Sequence↗

PubMed1991

Identification of human papillomaviruses in paraffin embedded cervical pathological tissues from Indian women by polymerase chain reaction.

The polymerase chain reaction (PCR) technology was used to identify human papillomaviruses (HPV) in 52 paraffin embedded cervical tissues from Indian women with chronic cervicitis, different grades of cervical dysplasia and invasive cervical carcinoma. The tissues were screened for amplification of the cellular beta-globin gene as well as of HPVs. Sets of primers designed to amplify a portion of the E6 gene of HPV 6, 11, 16, 18, 31, 33 and 35 were employed. HPV 6, 16 and 31 were identified in 58% of 33 beta-globin positive tissues as compared to 16% of 19 beta-globin negative tissues. HPV 11, 18, 33 and 35 were not identified in any of the specimens. Double infection of HPV 16 and 31 was observed in one case of carcinoma in situ and one case of invasive carcinoma. HPV-16 was the predominant virus in HPV positive cases of higher grades of cervical dysplasia (severe dysplasia and carcinoma in situ) and cervical cancer.

Carcinoma↗

PubMed1986

[Detection of immunoglobulin deposits in paraffin embedded skin with the peroxidase-antiperoxidase (PAP) method].

The peroxidase-antiperoxidase (PAP) technique allows the detection of immunoglobulin deposits in formalin-fixed, paraffin-embedded tissue. The PAP technique may be used as an alternative to the direct immunofluorescence method on frozen, unfixed skin. In addition, the PAP technique is suitable for retrospective evaluation of histological samples.

Fluorescent Antibody Technique↗

PubMed1987

Immunohistochemical characterization of a 183 KD myeloid-specific-DNA-binding protein in B5 fixed, paraffin-embedded tissues, and bone marrow aspirates by monoclonal antibody BM-1.

A monoclonal antibody, designated BM-1, which is reactive in B5 formalin-fixed, paraffin-embedded tissues, has been generated against a cytoplasmic and nuclear antigen expressed in human myeloid precursor cells and derived leukemias. Using the avidin-biotin-complex immunoperoxidase procedure, BM-1 was found to stain selectively myeloid precursor cells in normal bone marrow and mature granulocytes in the blood. In a screen of 26 normal adult and fetal human organs fixed in B5 formalin, BM-1 was negative in all nonhematopoietic tissues with the exception of tissue granulocytes and scattered cells in the peripheral cortex of the thymus. Likewise a screen of 30 solid tumor cell lines including a spectrum of carcinomas, sarcomas, and neural-derived tumors was negative. BM-1 was also negative with 21 T and B cell lymphomas and 11 Hodgkin's disease tumors. A preliminary study of tumors of the hematopoietic system revealed that BM-1 was reactive with M2 and M3 acute myelogenous leukemias (AML), chronic myelogenous leukemias (CML) and myelomonocytic leukemias, and granulocytic sarcomas. M1, M4, M5, and M6 AML clot preparations were negative in this study, indicating that BM-1 may have a role in the histopathologic diagnosis of myelogenous leukemia. Myeloid leukemic cell lines HL-60, ML-2, KG1, and TPH-1-O showed BM-1 nuclear and/or cytoplasmic reactivity in a subpopulation of cells, but erythroid and lymphoid leukemias and all lymphoma cell lines were negative. Immunoperoxidase studies of a panel of fetal tissues showed BM-1 positive cells in the peripheral cortex of the thymus and portal myelopoietic regions of the liver at 18 weeks gestation. Finally, DNA-cellulose and solid phase radioimmunoassay (RIA) techniques developed in our laboratory demonstrate that the BM-1 antigenic domain is reactive only after binding to eukaryotic but not prokaryotic single- or double-stranded DNA. Immunoblot techniques using a DNA-cellulose purified protein sample revealed that BM-1 recognizes a 183 kD protein. These studies indicate that BM-1 is recognizing a myeloid-specific antigen that, because of its DNA binding characteristics, may have an important role in the differentiation of myeloid cells at the molecular level.

Animals↗