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At least 19 recordsLinked to original sources

A comparative study of morphometric measurements of nucleoli in uveal melanomas from electron micrographs and plastic-embedded and paraffin-embedded sections.

Morphometric measurements of nucleoli were done on uveal melanomas from surviving and nonsurviving patients. The melanomas were embedded in paraffin and plastic, and measurement data from Papanicolaou-stained paraffin-embedded sections, toluidine blue-stained plastic-embedded sections and scanning transmission electron micrographs (STEM) of plastic-embedded sections were compared. The results showed that one parameter, the coefficient of variation (CV) of nucleolar area, correctly classified 80% of the cases as to survival when plastic-embedded material was used and 70% of the cases when paraffin-embedded material or STEM micrographs were used. The inverse standard deviation of the nucleolar area was a better predictor of outcome than was the CV of nucleolar area only in the paraffin-embedded sections. The nucleolar measurements were most easily and rapidly performed in the plastic-embedded sections.

Humans↗

Influence of fixation on human papillomavirus DNA detection in frozen and embedded paraffin lesions by in situ hybridization with biotinylated probes.

Series of frozen or paraffin-embedded tissues from various body sites, taken from non-immunosuppressed or immunosuppressed patients with persistent papilloma lesions were examined for the presence of group specific antigen from human papillomavirus (HPV) by indirect immunofluorescence or HPV DNA by in situ hybridization with biotinylated probes. We have shown that it is possible to detect HPV DNA after fixation of tissues in neutral formalin, Bouin's or Baker's solution. However, the sensitivity was reduced as compared to frozen tissues. The HPV DNA was detected in nuclei of heavily infected epithelial cells such as plantar or hand warts or in dispersed cells containing high copy numbers of HPV DNA from lesions such as squamous cell carcinomas or keratoacanthomas. In premalignant or malignant lesions of both immunosuppressed or non-immunosuppressed patients, HPV DNA was rarely detected after fixation. HPV types commonly described for skin and genital samples were identified in non-immunosuppressed patients, whereas in transplant recipients oncogenic HPV type 16 was identified in benign warts as well as in premalignant or malignant lesions. Positive reactions with several HPV types were more frequent in lesions from grafted patients than from the normal population. Virus antigen was detectable more frequently in frozen sections than in fixed tissues. Our findings indicate that in situ hybridization is an appropriate and rapid technique to study the presence of HPV infection. However, numerous controls are needed to avoid misinterpretations.

Antigens, Viral↗

Haemopoiesis in human fetal and embryonic liver. Immunohistochemical determination in B5-fixed paraffin-embedded tissues.

Paraffin embedded tissue reactive monoclonal antibodies were used to study human embryonal and fetal haemopoiesis, combining optimal morphology with immunohistological determination of haemopoietic cell subtypes and their microenvironment. Seven embryonal and twelve fetal liver specimens were studied, having been fixed in B5-fixative and embedded in paraffin. The different haemopoietic lineages each showed their own immunophenotype and distribution; intercellular and microenvironmental relationships were easily determined. Erythroid cells are reactive with VIE-G4, LN1, and MT1, sometimes partly surrounding a central macrophage. Myelomonocytic cells react with LCA, MT1, MB3, LN2, and anti-lysozyme, and from 14 weeks onwards with LN3. Lymphoid cells show LCA, MT1, MT2, MB1, MB2, MB3, and LN2 reactivity. In a few cases some scarce My10+ early progenitor cells were seen. An important finding is the extensive MT1-reactivity distributed over all haemopoietic lineages, and the demonstration of immature haemopoietic blast cells exclusively expressing the MT1 antigen. Further studies employing MT1 are necessary to delineate the extent of the distribution and the possible function of the antigen. Use of the MT1 mAb may contribute to the elucidation of the exact nature of the haemopoietic blast cells and their place in haemopoietic development.

Antibodies, Monoclonal↗

[Utility of the paraffin-embedded section method on the detection of estrogen receptor from breast cancer tissues--comparison of the paraffin-embedded section method (6F11 and 1D5) with frozen section (H222) and dextran-coated charcoal (DCC) ones].

From March 1988 to December 1990, we detected estrogen receptor (ER) from breast cancer tissues with the dextran-coated charcoal (DCC) method. From September 1990 to March 1998, we repeated the above with the frozen section method (cloneH222; DAINABOT). With the paraffin-embedded section method using two antibodies of anti-ER (clone6F11; NOVOCASTRA and clone 1D5; MBL), we examined the ER of the same 185 primary breast cancer tissues. We had already detected these tissues with the frozen section method, and we also applied the same procedure for the 43 primary breast cancer tissues which had already been detected with the DCC method. We compared these data. The positive rates of ER with DCC, H222, 6F11 and 1D5 were 49%, 53%, 53% and 52% respectively, which were within the reported range. The accuracy between H222 and 6F11 which was calculated as the percentage that were in positive and negative concordance by the two methods, was 88%. The accuracies between H222 and 1D5, between 6F11 and 1D5, between DCC and 6F11, between DCC and 1D5 were respectively 89%, 96%, 79%, and 77%. Although the accuracy between DCC and the paraffin-embedded section was not necessarily high, we obtained a higher concordance between the frozen and paraffin-embedded sections. The highest concordance existed between 6F11 and 1D5. The 30% of negative cases with DCC were positive with paraffin-embedded section. Among these methods of ER detection from breast cancer tissues, the paraffin-embedded section method seemed to be the most useful.

Breast Neoplasms↗

Immunohistochemical evaluation of myeloid leukemia infiltrates (granulocytic sarcomas) in formaldehyde-fixed, paraffin-embedded tissue.

Paraffin sections of granulocytic sarcomas (GS) (n = 30) were immunohistochemically evaluated for CD3, CD15 (LeuM1), CD20 (L26), CD31, CD34, CD43, CD45, CD68 (KP1), lysozyme, myeloperoxidase (BM1), CD45RO (UCHL1), and LN5 with an avidin-biotin amplification system and a peroxidase-based color development system with DAB as a chromogen. CD45 positivity was present in all lymphomas and 24 of 25 granulocytic sarcomas. Lysozyme and CD43 labeled 26 of 29 granulocytic sarcomas, showing intense cytoplasmic staining. LN5 (membrane-staining) and CD68 (subtle cytoplasmic caplike staining) were found in 20 of 30 cases, often only focally. BM1 and CD15 mainly labeled maturing granulocytes and mostly were negative in primitive myeloid cells. Myeloid progenitor cell antigens CD31 and CD34 were seen in 7 and 12 of 30 cases, respectively. They seemed to recognize different subsets of myeloid leukemia infiltrates (16 cases positive for at least one); the use of CD31 and CD34 for defining these subsets should be evaluated further. Features suggesting a dual phenotype--T-cell and myeloid (positive for CD3, CD68, and lysozyme)--were documented in two cases. In contrast, lymphoblastic lymphomas (n = 4) were positive for CD3 and CD43 but negative for CD68, lysozyme, CD31, CD34, LN5, and myeloperoxidase. Lymphocytic lymphomas (n = 10) were positive for CD20 and CD43 but negative for all other markers. Small, round-cell tumors (n = 15) were negative for all markers. If T-cell and B-cell differentiation can be excluded with other markers, CD43+ is a sensitive marker for myeloid differentiation. Our results show that several markers are useful in the identification of myeloid leukemia infiltrates and in distinguishing them from lymphoblastic and lymphocytic lymphomas and small round-cell tumors in formaldehyde-fixed, paraffin-embedded tissue.

Adult↗

A simple procedure to obtain one-micrometer sections of routinely embedded paraffin material.

By freezing blocks of paraffin-embedded tissues to a convenient temperature it is possible to obtain routinely 1 micron sections that can be further processed as normal thicker sections. Normal and disposable steel knives can be used and the staining time should be increased in most procedures. Gradual freezing of blocks to the temperature of dry ice is the simplest and safest way to obtain an adequate temperature. The best results were obtained using as fixative 4% paraformaldehyde in phosphate buffered saline solution.

Animals↗

[Immunohistologic differential diagnosis of skin tumors in routinely embedded paraffin sections].

Thirty-nine skin tumors of epithelial, mesenchymal, and neuroectodermal origin were studied using antibodies against intermediate filaments and other cell proteins. Formol-fixed and paraffin-embedded material was reconstituted and stained with antibodies against epithelial cells (keratin, epithelial membrane antigen, carcinoembryonic antigen), mesenchymal and histiocytic cells (vimentin, alpha-1-antichymotrypsin, alpha-1-antitrypsin, lysozyme), nerve tissue (neurofilament, glial fibrillary acidic protein, myelin basic protein, myelin-associated protein, neuron-specific enolase), vessels (factor-VIII-related protein), basal cell lamina (laminin) and S-100 protein. Tumor cells displayed the same antibody pattern found in the normal cell type. It is recommended that immunotyping be started with three antibodies to allow gross classification into epithelial (keratin positive), mesenchymal (vimentin positive) and neuroectodermal (vimentin and S-100 protein positive) tumors; then, in a second step, the tumors can be subclassified by the other more specific antibodies listed above. All antibodies used in this study are commercially available and provide reliable results.

Antigens, Neoplasm↗

Quantitative comparison of pretreatment regimens used to sensitize in situ hybridization using oligonucleotide probes on paraffin-embedded brain tissue.

Paraffin embedding of tissue is generally perceived to dramatically reduce RNA detectability. As a consequence, in situ hybridization on paraffin-embedded tissue is largely confined to detection of high-copy RNA species (e.g., viral RNA) and/or to detection using typically more sensitive cDNA probes or riboprobes. In this study, several procedures for in situ hybridization on paraffin-embedded rat tissue using oligonucleotide probes complementary to cellular transcripts were developed and quantitatively compared. Certain pretreatments showed marked increases in sensitivity compared to untreated sections. Furthermore, through quantitative assessment using image analysis, sensitivity of optimal pretreatments was equal to that of routinely used fresh-frozen, postfixed tissue sections. The development of such techniques permitting in situ hybridization to be carried out on paraffin-embedded tissue allows a comparison of protein and mRNA distribution to be made in adjacent sections and provides the potential for double labeling by in situ hybridization and immunohistochemistry which may not be possible on post-fixed frozen sections.

Animals↗

Hairy-cell leukaemia: an immunoperoxidase study of paraffin-embedded tissues.

Paraffin sections of a variety of tissues from 12 patients with typical hairy-cell leukaemia (HCL) were stained for immunoglobulin heavy and light chains by the peroxidase-antiperoxidase (PAP) technique. Plasma cells were frequent, particularly in a lymph node from a severely infected patient. The reactive nature of the plasma cells of HCL was suggested by the fact that there was no restriction of light-chain expression, although viable hairy cells were shown to express monoclonal surface immunoglobulin. This, together with the absence by both light and electron microscopy of forms intermediate between hairy cells and plasma cells and the lack of ribosome-lamella complexes in the plasma cells, suggested that hairy cells do not differentiate into plasma cells. Although hairy cells are known to contain immunoglobulin, this was not demonstrable in hairy cells in the paraffin-embedded tissue. The PAP technique was also useful for demonstrating abundant splenic macrophages in HCL.

Humans↗

Immunohistochemical detection of T-cell subsets and other leukocytes in paraffin-embedded rat and mouse tissues with monoclonal antibodies.

We describe a method for immunohistochemical localization of T-cells, CD4+ T-cells, CD8+ T-cells, B-cells, activated lymphocytes, major histocompatibility complex (MHC) class II antigens, macrophages, dendritic cells, and granulocytes in rat and mouse tissue fixed in periodate-lysine-paraformaldehyde (PLP) and embedded in paraffin. Rat and mouse spleen and eyes were fixed in PLP for 18-24 hr, rapidly dehydrated, infiltrated under vacuum with paraffin at 54 degrees C, sectioned, and stained with appropriate monoclonal antibodies (MAbs). Sections of PLP-fixed, paraffin-embedded spleen were compared with acetone-fixed frozen spleen sections with respect to morphology and staining quality. Nine of 10 MAbs to rat antigens and eight of nine MAbs to mouse antigens stained paraffin sections equally or more intensely than frozen sections. The two MAbs that showed weaker staining still gave good staining on paraffin sections. Paraffin-embedded rat and mouse eyes were easier to section serially than frozen eyes, showed superior morphology, and individually stained cells were readily identified. Therefore, a combination of PLP fixation and low-temperature paraffin embedding permits detection of the major types of immune cell in rat and mouse tissues while maintaining good morphology, particularly in diseased, damaged, or delicate tissues.

Animals↗

The duration of fixation influences the yield of HCV cDNA-PCR products from formalin-fixed, paraffin-embedded liver tissue.

The extent of hepatitis C virus (HCV) RNA loss during increasing periods of fixation of liver tissue in formalin was examined. For this purpose human liver tissue, known to be HCV RNA positive and stored at -70 degrees C until use, was cut into small slices (n = 9), which were fixed in phosphate-buffered formalin for increasing periods of time before embedding in paraffin. Nucleic acids were extracted from each slice of formalin-fixed, paraffin-embedded liver tissue and HCV RNA loss during fixation was semi-quantified by testing 10-fold dilutions of each extract in an HCV cDNA-PCR assay. The endpoint dilution for HCV RNA detection by cDNA-PCR in liver slices fixed in buffered formalin for 8-24 h was comparable to the endpoint dilutions found for 'fresh', non-fixed liver slices. After fixation for 2-3 days the endpoint dilution for HCV RNA detection was 10(2) to 10(3)-fold less. After 2-4 weeks of formalin-fixation, HCV RNA was detectable from undiluted nucleic acid extracts only. It is concluded that formalin-fixed, paraffin-embedded liver biopsies can be used for HCV RNA detection by cDNA-PCR, on condition that the liver tissue has been embedded in paraffin within 24 h of formalin-fixation.

Biopsy↗

Immunohistochemical detection of cytokines in paraffin-embedded mouse tissues.

We have successfully developed a method for the immunohistochemical detection of interleukin 2 (IL-2), IL-4, IL-6, IL-10O, IFNgamma and TNFalpha using monoclonal antibodies (MAb), in sections of mouse tissue embedded in paraffin wax. The method involved fixation in periodate-lysine-paraformaldehyde (PLP), rapid dehydration and infiltration under vacuum with paraffin wax at 54 degrees C. Comparative observations demonstrated that the method gives equivalent or better results than formaldehyde fixed, frozen sections. Since reliable controls, both positive and negative, are paramount for interpretation of immunohistochemical staining, such controls were determined. The following tissues were shown to be suitable as positive controls when using paraffin-embedding: spleen for the detection of TNFalpha, small intestine for IL-2, IL-4 and IL-10, and HSV-1 infected eyes for IL-6 and IFNgamma. We conclude that PLP fixation and low temperature paraffin-embedding is a method which provides both preservation of excellent tissue morphology and reliable immunohistochemical identification of cytokines. These attributes will be invaluable in a wide variety of experimental situations.

Animals↗

Detection of avian polyomavirus infection by polymerase chain reaction using formalin-fixed, paraffin-embedded tissues.

Avian polyomavirus infection in psittacines was diagnosed in tissues by the use of polymerase chain reaction (PCR) test. The tissues used in the procedure were either formalin-fixed tissues embedded in paraffin blocks or fresh tissues (heart, liver, and spleen) collected from the psittacines during necropsy. DNA was extracted from these tissues and was tested with the published primers for avian polyomavirus VP1 gene in the PCR that yielded an amplicon of 550 base pair size, which was then visualized by electrophoresis. The amplicon size was consistent with avian polyomavirus. The PCR test was found to be an effective method for identifying avian polyomavirus infection in both formalin-fixed, paraffin-embedded and fresh tissues from psittacine birds of different age groups.

Animals↗

Whole genome amplification and molecular genetic analysis of DNA from paraffin-embedded prostate adenocarcinoma tumor tissue.

PURPOSE: Often tissues obtained from prostate adenocarcinoma tumors embedded in paraffin are heterogeneous in cell type and must be carefully microdissected to acquire tissue fragments that provide homogeneous aliquots of tumor clones. Such tissue fragments rarely contain sufficient DNA to perform genomic characterization needed as an early step in localizing relevant oncogenes or tumor suppressor genes. We report that PCR using a degenerate oligonucleotide primer (DOP-PCR) can be applied to DNA samples from microdissected paraffin-embedded prostate adenocarcinomas, and this provides sufficient product for fluorescent allelic imbalance measurements or comparative genomic hybridization (CGH). MATERIALS AND METHODS: Samples were selected to be representative of those routinely obtained during prostatectomies, based on typical tumor stages (T2 and T3) and Gleason grades (range 3 +3 to 4 +5). For DNA analysis without prior DOP-PCR, only large tumors were selected to be sectioned. More than 50 specimens were analyzed. Close comparison of data obtained from analysis of DOP-PCR with those from non-DOP DNA was obtained on a subset 8 samples. To compare the allelic balance of DOP-PCR amplified DNA with that measured for non-DOP DNA, we analyzed allelic ratios on DNA from 5 different tissue samples processed by both microdissection and conventional sectioning. RESULTS: Systematic comparison of allelic imbalance results shows close similarity between DOP-PCR amplified product and non-DOP DNA, indicating that PCR product is a valid representation of the tumor genome. In addition, the difference between allelic balance and imbalance is more distinctive when microdissection followed by DOP-PCR is performed. Performing CGH on products of DOP-PCR also shows distinctive regional copy number alterations in DNA from microdissected tumor tissue. CONCLUSION: Either of these procedures allows distinction between benign and malignant genomes, and also allows independent analysis of genomic alterations in different portions of tumors. They also may be applied clinically for genomic characterization of small foci that frequently appear in prostates of elderly men who are showing no obvious pathological symptoms of adenocarcinoma.

Adenocarcinoma↗

Interphase cytogenetics of non-Hodgkin's lymphoma using non-fluorescent in situ hybridization in paraffin embedded tissue.

Paraffin-embedded tissue samples from 30 cases of non-Hodgkin's lymphoma(NHL) and 10 of reactive hyperplasia, were processed for interphase cytogenetic chromosomal study. We performed non-fluorescent in situ hybridization(NFISH) using the enzymatic method with digoxigenin-labeled DNA centromeric probes for chromosome 7,12,18 and X, and a painting probe for chromosome 18. Chromosomal aberrations were observed in 27(90%) out of 30 cases of NHL. The most commonly observed numerical aberration was extracopy of X chromosome. There were some characteristic aberrations corresponding to each grade and group of NHL by International Working Formulation: In low grade NHL(9 cases), a third were associated with extracopy of chromosome 12, and disomy X was frequently found in small lymphocytic lymphoma(75%). With intermediate grade(16 cases), tetraploidy(25%), translocation of chromosome 18(25%), and extracopy of chromosome 18(19%) were characteristically associated. These results suggest that interphase NFISH is an easily performable method in retrograde cytogenetic study of archival materials. Some specifically correlated chromosomal aberrations corresponding to the histopathologic grades and groups could provide us more valuable information for determining pathologic diagnosis and assessing the clinical outcome of NHL.

Chromosome Aberrations↗

Electron microscopic examination of cutaneous lesions by the quick re-embedding method from paraffin-embedded blocks.

We attempted to evaluate whether Widéhn's quick re-embedding method from paraffin blocks is useful for dermatopathological diagnosis. Regarding fine preservation of nuclei, tono-fibrils and desmosomes of keratinocytes in normal skin, we could recognize no difference between the quick re-embedding method and traditional re-embedding methods. However, preservation of mitochondria and Birbeck granules in Langerhans cells was poor regardless of the method used. Furthermore, we studied the ultrastructural features of some viral skin diseases including molluscum contagiosum, herpes simplex, varicella-zoster and verruca vulgaris, and some skin tumors, including angioleiomyoma, angiosarcoma, Merkel cell carcinoma and amelanotic melanoma using the quick re-embedding method. We determined that all viral structures were sufficiently preserved by the quick method to observe the virions and development of the virus. Myofilaments and dense bodies of angioleiomyoma, Weibel-Palade bodies of angiosarcoma, neurosecretory granules of Merkel cell carcinoma and melanosomes of amelanotic melanoma were recognized by the quick method. From these results, we concluded that the quick re-embedding method is useful for the diagnosis of skin diseases, especially viral skin diseases and some skin tumors.

Angiomyoma↗

Immunofluorescent detection of alpha1-antitrypsin in paraffin embedded liver tissue.

Alpha1-antitrypsin was detected by indirect immunofluorescence in frozen sections of liver biopsies from patients with clinically and biochemically proven alpha1-antitrypsin deficiency. The antigen could also be demonstrated in those liver specimens of the same patients which were fixed in Bouin's fluid and embedded in paraffin. The cellular localization and the brightness of the fluorescence were the same in both frozen and paraffin sections. Four additional biopsies from three other patients were selected on the basis of PAS-positive diastase-resistant inclusions reported in the hepatocytes. All these biopsies showed bright fluorescence in the cytoplasm of the liver cells although one of the biopsies was stored for as long as eight years. Specific fluorescence was constantly found in the periportal hepatocytes with varying degrees of positivity. No fluorescence was observed in the six control biopsies from patients with various other liver diseases. These findings prove that paraffin embedded specimens are suitable for immunofluorescence detection of alpha1-antitrypsin and that a retrospective study on old paraffin blocks is possible.

Adult↗

Proliferating cell nuclear antigen (PCNA) immunostaining as an alternative to bromodeoxyuridine (BrdU) immunostaining for brain tumours in paraffin embedded sections.

Immunohistochemical staining for proliferating cell nuclear antigen (PCNA) and BrdU using anti-PCNA and anti-BrdU monoclonal antibodies, respectively, was performed in 16 human brain tumours, including 3 glioblastomas multiforme, 2 anaplastic astrocytomas, 1 cerebellar astrocytoma, 2 recurrent meningiomas, 4 non-recurrent meningiomas, 3 neurinomas and 1 medulloblastoma. Patients with brain tumours received an injection of bromodeoxyuridine (BrdU) intravenously during surgery, and tumour specimens were fixed in 70% ethanol and embedded in paraffin. The percentage of positive cells for PCNA was compared with a BrdU labelling index using adjacent paraffin-embedded sections. The percentage of PCNA-positive cells was correlated with the BrdU labelling index and the histological malignancy of the brain tumours. The correlation coefficient was 0.84. This suggests that the immunohistochemical staining for PCNA in paraffin sections is a good alternative to the BrdU labelling index.

Antigens, Neoplasm↗