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At least 1,279 records · Page 71Linked to original sources
PubMed1988

DNA flow cytometry in metastases and a recurrency of malignant melanomas. A comparison of results from fresh and paraffin embedded material.

Single cell suspensions from 16 biopsies from 15 patients with metastatic or recurrent malignant melanoma were prepared according to the method described by Vindeløv (1977) and the nuclear DNA content was measured by a laboratory-built flow cytometer. The DNA histograms thus obtained were compared with those obtained from suspensions of single nuclei from the same biopsies after formalin fixation and paraffin embedding, according to the method of Hedley et al. (1983). Linear regression analysis of ploidy values from fresh material compared with those from paraffin blocks showed a strong correlation (R2 = 0.85), while that of the S-phase fraction was somewhat weaker (R2 = 0.66). It is concluded that archival wax preparations of malignant melanoma cell populations are suitable for FCM analysis of ploidy, and to a lesser extent for analysis of fraction of cells in various cell cycle phases.

DNA↗
PubMed1985

Immunocytochemical demonstration of cytochrome c oxidase with an immunoperoxidase method: a specific stain for mitochondria in formalin-fixed and paraffin-embedded human tissues.

Cytochrome c oxidase (CO) is the terminal electron carrier of the respiratory chain and is localized exclusively in the inner membrane of the mitochondria. Using a specific rabbit antiserum against bovine heart CO, mitochondria were specifically stained in sections of formalin-fixed paraffin-embedded human tissues by an immunoperoxidase method. The intensity of the immunostaining in different human tissues correlated mainly with the number of mitochondria and abundance of mitochondrial cristae, i.e., surface area of the inner mitochondrial membrane. Mitochondrion-rich cells, such as myocardial and gastric parietal cells, had very strong cytoplasmic staining. This technique was especially useful for the specific identification of oncocytes in normal tissues and in lesions composed of oncocytes. In addition, the immunoperoxidase method for CO makes possible retrospective investigations of lesions composed of oncocytes, since routine paraffin blocks of formalin-fixed tissue are quite suitable for such studies.

Cell Transformation, Neoplastic↗
PubMed1987

Flow cytometric DNA measurements in paraffin-embedded bladder carcinoma tissue before and after precystectomy radiotherapy.

From 1976 through 1983, 48 patients with T2/T3 bladder carcinomas were treated with pre-operative radiotherapy (46 Gy) and total cystectomy. DNA histograms were recorded by flow cytometry (FCM) from all pre-treatment paraffin-embedded tumour biopsies and, if still present after radiotherapy, from tumour tissue from the cystectomy specimen. Five patients were excluded from the study because no DNA histograms could be recorded due to extensive destruction of the cell nuclei during preparation. Thus, 43 patients are completely evaluable. Before the start of radiotherapy, 32 bladder carcinomas were interpreted as non-diploid, whereas 11 were diploid. Non-diploidy of the pre-treatment biopsy was associated with radiotherapy-induced stage reduction (p = 0.13). The survival rates in patients with diploid and non-diploid tumours were 65% and 45% respectively at 4 years (p = 0.13). Although not statistically significant, our results suggest that DNA-FCM may provide clinically relevant information about the tumour biology and response to radiotherapy concerning bladder carcinomas.

Adult↗
PubMed1986

Enzyme histochemical demonstration of hairy cell leukaemia in paraffin-embedded tissue sections.

Hairy cell leukaemia is a form of leukaemia difficult to diagnose since pancytopenia is often present. Hairy cells contain tartrate-resistant acid phosphatase, and this factor is utilised in the diagnosis of the condition. This study confirms that it is also possible to demonstrate tartrate-resistant acid phosphatase in leukaemic infiltrates in formalin fixed paraffin-embedded tissue sections.

Acid Phosphatase↗
PubMed1992

Characterization of human gliomas by a monoclonal antibody both on tissue culture and paraffin-embedded sections.

A monoclonal antibody designated OITIC3-11 was produced against GFAP positive human glioblastoma multiforme tumour cells. The specificity of the monoclonal antibody was tested on different types of human brain tumours and on normal adult brain both on tissue cultures and paraffin-embedded sections. The OITIC3-11 monoclonal antibody reacted with 16 of 18 malignant and 1 of 6 benign gliomas but did not react with meningioma, pituitary adenoma, metastatic brain tumours and normal adult brain tissue.

Animals↗
PubMed1988

Evaluation of different fixatives and treatments for immunohistochemical demonstration of Coxiella burnetti in paraffin-embedded tissues.

Various fixatives and treatments such as acetone, methanol, Bouin fixative, modified Bouin fixative, 10% Formalin, modified methacarn, periodate-lysine-paraformaldehyde, acetone-methyl benzoate-xylene, and EDTA were evaluated for their effect on the immunoreactivity of Coxiella burnetii in paraffin-embedded tissues by using the avidin-biotin-peroxidase complex and the peroxidase-antiperoxidase procedure. C. burnetii antigen was shown to be present in liver, spleen, and uterus tissues of experimentally infected mice by all methods of fixation and treatment. A positive immunoreaction was seen in cytoplasmic vacuoles of macrophages, as extracellular rod-shaped organisms, and as residual particulate extra- and intracellular debris. Immunoreactivity and cellular preservation, however, varied substantially with the individual fixatives. Optimal immunostaining of C. burnetii was achieved by EDTA treatment and Bouin and acetone fixation. The avidin-biotin-peroxidase technique proved to be slightly more sensitive than the peroxidase-antiperoxidase procedure when primary antibody dilution was used as the criterion for sensitivity.

Animals↗
PubMed1978

Intracellular Ig identification on paraffin-embedded solitary plasmacytoid proliferation: a routine method to define the biological nature of plasma cells.

The difficulty to recognize morphologically the biological nature of the exuberant plasma cell proliferations is known by every pathologist. Therefore, an immunohistochemical method has been applied to routine paraffin-embedded sections of biopsies from 26 patients suspected to bear a solitary plasmacytoma. The method has allowed to distinguish between monoclonal (likely to be neoplastic) and polyclonal cases (likely to be reactive).

Clone Cells↗
PubMed1994

Quality control considerations for Ki-67 detection and quantitation in paraffin-embedded tissue.

Proliferative activity has prognostic significance in many solid tumors. Immunohistochemical analysis of tumor proliferation may be accomplished with the Ki-67 monoclonal antibody which recognizes a nuclear antigen expressed throughout the cell cycle. This antibody, however, cannot be used with formalin-fixed, paraffin-embedded tissue. Recently, a Ki-67 equivalent murine monoclonal antibody (MIB-a; AMAC, Inc., Westbrook, ME) was generated which can detect tumor proliferative activity in routinely processed tissue with microwave oven heating. Using quantiative image analysis, we assessed the effect of delay in fixation, total time of formalin fixation, and microwave heating time on the immunoreactivity of this antibody. The effect of time to fixation (0, 2, 4, 8, or 24 hours) on MIB-1 immunostaining was determined in various tumor tissues using image analysis. No significant difference in positive nuclear area was observed for tissues in which fixation was delayed for as long as 8 hours relative to controls. A 24-hour fixation delay resulted in a small decrease in positive nuclear area was observed for tissues in which fixation was delayed for as long as 8 hours relative to controls. A 24-hour fixation delay resulted in a small decrease in positive nuclear area relative to controls. The effect of fixation time (4, 24, or 48 hours) and microwave oven heating time on MIB-1 immunostaining was studied in tonsil tissue, and quantitated by image analysis. Good MIB-1 immunostaining was observed for all microwave oven heating times in tissue fixed for 4 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1994

DNA analysis by flow cytometry of paraffin embedded core biopsies of the prostate.

The majority of literature concerning DNA analysis of prostate cancer involves testing formalin-fixed prostatectomy tissue, fresh or formalin-fixed transurethral resections of the prostate (TURP), or fresh core biopsies. We were interested if flow cytometry could analyze the DNA of formalin-fixed, paraffin-embedded, core biopsies separated into normal versus malignant segments. Of the 50 potentially available samples for analysis representing 11 controls of normal core tissue and 39 core biopsies from the 11 patients, one patient had no normal tissue, one core had no malignancy, and three cores had no tissue visibly remaining in the paraffin blocks for analysis. Therefore, of 45 actual samples available for processing, sometimes representing segments as small as 0.2 cm, separate segments containing malignant glands or normal glands were excised from the blocks, and processed separately by the Hedley technique. Forty-four of the 45 available samples produced interpretable DNA histograms as defined by discernible G0/G1 peaks, a calculable cell cycle analysis, and the qualitative appearance of a "smooth" histogram appearance, reflecting sufficient nuclei were analyzed. This is the first report to our knowledge where flow cytometry has successfully been used to analyze paraffin blocks of core biopsies which were, in addition, separated into malignant versus normal enriched segments.

Biopsy↗
PubMed2005

Immunolocalization of MAP-2 in routinely formalin-fixed, paraffin-embedded guinea pig brain sections using microwave irradiation: a comparison of different combinations of antibody clones and antigen retrieval buffer solutions.

The present study was designed to evaluate the efficacy of different microwave pretreatment methods to retrieve microtubule-associated protein 2 (MAP-2) immunoreactivity in formalin-fixed, paraffin-embedded guinea pig brain sections. Brain sections, microwave pretreated in boiling sodium citrate, citric acid, Tris hydrochloride, and EDTA buffers of pH 4, 6, and 8, were labeled with four different clones of MAP-2 monoclonal antibodies. No MAP-2 immunoreactivity was observed in control sections processed without microwave pretreatment. Optimal MAP-2 immunoreactivity was observed only when MAP-2 antibody clone AP18 was used in conjunction with citric acid buffer of pH 6.0. Using this combination, brain sections from nerve agent soman-exposed guinea pigs were found to exhibit marked reduction in MAP-2 immunostaining in the hippocampus. These observations suggest that the clone of the antibody in addition to the type and pH of antigen retrieval (AR) solution are important variables to be considered for establishing an optimal AR technique. When studying counterpart antigens of species other than that to which the antibodies were originally raised, different antibody clones must be tested in combination with different microwave-assisted AR (MAR) methods. This MAR method makes it possible to conduct retrospective studies on archival guinea pig brain paraffin blocks to evaluate changes in neuronal MAP-2 expression as a consequence of chemical warfare nerve agent toxicity.

Animals↗
PubMed1987

The rapid detection of Acanthamoeba in paraffin-embedded sections of corneal tissue with calcofluor white.

Acanthamoeba keratitis is a difficult diagnosis to make with routine stains and cultures. Gram's, Giemsa, and hematoxylin-eosin stains do not differentially stain Acanthamoeba, making the detection of organisms difficult. Trophozoite and cyst forms in paraffin-embedded corneal tissue sections can be rapidly and differentially stained with calcofluor white. Under the fluorescence microscope, the trophozoites are bright red-orange, and cyst cell walls fluoresce bright apple-green with red-orange cytoplasm. Retrospective identification can be made by destaining hematoxylin-eosin-stained sections. Digesting background corneal tissue with trypsin or collagenase and hyaluronidase solutions helps to more readily identify trophozoites.

Acanthamoeba↗
PubMed1992

Frequent expression of haemopoietic and non-haemopoietic antigens by neoplastic plasma cells: an immunohistochemical study using formalin-fixed, paraffin-embedded tissue.

There is increasing evidence that neoplastic plasma cells express various haemopoietic and non-haemopoietic antigens. Since this issue could raise problems in diagnostic histopathology, we have investigated 51 cases of multiple myeloma (plasmacytoma) systematically with a broad panel of antibodies applicable on paraffin-embedded and mildly decalcified tissue. In approximately 90% of the cases the neoplastic plasma cells reacted with at least one antibody detecting haemopoietic antigens: MB2 (75%), DF-T1/CD 43 (59%), UCHL1/CD 45RO (47%), Ki-B3 (41%), anti-LCA/CD 45 (40%), L26/CD 20 (26%), 4KB5/CD 45RA (18%), Ber H2/CD 30 (10%), anti-neutrophil elastase (4%), anti-Leu-7/CD 57 (8%), Dako-M1/CD 15 (2%), KP1/CD 68 (2%) and anti-glycoprotein IIIa (2%). In approximately 70% of the cases the cells reacted with antibodies against non-haemopoietic antigens: anti-epithelial membrane antigen (65%), BMA120 (53%), anti-vimentin (44%), anti-pan-cytokeratin/KL1 (8%), anti-carcino-embryonic antigen (6%) and HMB45 (6%). Lack of awareness of the frequent expression of both haemopoietic and non-haemopoietic antigens by neoplastic plasma cells could lead to mis-diagnosis of plasmacytomas as malignant lymphomas or even as carcinomas or sarcomas.

Adult↗
PubMed1991

Detection of estrogen receptor in paraffin-embedded sections of breast carcinoma by immunohistochemistry and in situ hybridization.

Biopsy specimens of small breast carcinomas are often insufficient for both diagnosis and the biochemical determination of estrogen receptor (ER) protein. Recent reports from various laboratories have shown the utility of immunohistochemical detection of ER protein in paraffin-embedded tissue sections. We used immunohistochemical (IHC) staining with the Abbott ER antibody (H222) and in situ hybridization (ISH) analysis with a 35S-labeled and a biotinylated oligonucleotide probe to detect ER protein and messenger RNA (mRNA) in tissue sections of 53 breast carcinomas. The dextran-coated charcoal (DCC) assay of these same cases revealed positive receptor levels in 31 of 53 cases, whereas the IHC method was positive in 33 of 53 cases. ISH for detection of ER mRNA was more sensitive than IHC or the biochemical assay for estrogen binding proteins, as the isotopic probe detected ER mRNA in 47 of 53 cases, whereas the biotinylated probe detected ER mRNA in 46 of 53 cases. These results indicate that ER protein can be readily detected in enzyme-treated paraffin tissue sections and that the IHC detection of ER protein correlates highly with the DCC assay. ISH with isotopic and biotinylated probes detects ER mRNA in most cases found to be positive for ER protein and also in many cases without detectable ER protein. Although detection of ER protein in paraffin sections correlates highly with the biochemical assay in this report and in other reported studies, the clinical significance of increased sensitivity by ISH is unknown and must await clinical correlative follow-up studies.

Breast Neoplasms↗
PubMed1998

PCR diagnosis on formalin-fixed, paraffin-embedded tissues with acid-fast stain and culture negativity in chronic dialysis patients of cervico-mediastinal tuberculous lymphadenitis.

BACKGROUND: Bacteriologic studies often provide negative results in tuberculous infection, and do not favour early diagnosis. Polymerase chain reaction (PCR) is known to diagnose tuberculosis quickly. With this in mind, we used PCR to detect mycobacterial DNA on formalin-fixed, paraffin-embedded tissues with acid-fast stain and culture negativity in two dialysis patients with cervico-mediastinal lymphadenopathy. METHODS: Sections of neck lymph nodes were cut at two different levels. At each level, two semi-adjacent sections with a thickness of 5 microm each were cut using standard microtomes with disposable blades. The first section mounted on a glass slide was stained by Ziehl-Neelsen, and the second section was examined by PCR based on a 123 bp fragment of IS6110 that is specific for the Mycobacterium tuberculosis complex. RESULTS: The histology of lymph nodes disclosed inflammatory necrotizing granulomas, but acid-fast stain for M. tuberculosis was negative in the two patients. DNA of M. tuberculosis was detected in lymph node samples from each patient by PCR on the IS6110 element and by dot-blot hybridization. CONCLUSIONS: PCR assay is a potentially useful approach for early and rapid diagnosis of tuberculous lymphadenitis in chronic dialysis patients, since mycobacterial staining and culture often provide negative results.

Adult↗
PubMed1995

Detection of TP53 gene mutation in human meningiomas: a study using immunohistochemistry, polymerase chain reaction/single-strand conformation polymorphism and DNA sequencing techniques on paraffin-embedded samples.

Mutations in the TP53 tumor suppressor gene have been studied in different types of brain tumors. Little is known about this genetic event in human meningioma, a mostly benign tumor. To investigate the frequency of TP53 gene mutations in human tumors derived from meningeal tissues, paraffin-embedded tissues from 30 cases (including 2 malignant and 4 atypical meningiomas, as well as 2 hemangioblastomas and 3 hemangiopericytomas) were screened by immunohistochemistry. Polymerase chain reaction/single strand conformational polymorphism (PCR/SSCP) and direct DNA sequencing were thereafter performed in selected cases. Nuclear p53 staining was not seen in any of the 19 benign meningiomas tested, while atypical meningiomas, hemangioblastomas, and hemangiopericytomas displayed nuclear staining in a subpopulation of tumor cells in 4 out of 5, 2 out of 2, and 3 out of 3 cases, respectively. One malignant meningioma showed an intense nuclear staining and a band shift in SSCP. In this case, we identified a mutation in the TP53 gene at codon 161 changing GCC to ACC and resulting in an alteration of alanine to threonine in this position. Our results indicate that TP53 gene mutation may be considered as a marker for malignant transformation in meningioma. p53 immunoreactivity, even in the absence of detectable gene mutation, is also associated with atypia and does not appear in regular benign meningiomas.

Adult↗
PubMed1987

A freeze-dried paraffin-embedded tissue technique for immunohistochemical studies requiring unfixed tissue from the nervous system.

Immunohistochemical studies using monoclonal antibodies against epitopes in neural tissues frequently require tissue which has not been fixed in formalin. In the past, such studies have been performed on frozen (cryostat) sections despite the general loss of morphological preservation compared with paraffin sections. In the present report, a detailed, versatile method for obtaining improved morphological preservation of "unfixed" neural tissue is described which utilizes freeze-dried paraffin-embedded sections (a modified Altmann-Gersh technique). The advantages of using mercury flotation of freeze-dried sections are particularly stressed.

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↗
PubMed1980

[Tissue artefacts by the use of overheated forceps for paraffin embedding (author's transl)].

Histologic work-up of tissue specimens, especially from endoscopic biopsies, requires the use of fine forceps for orientation and dressing in fluid paraffin during the embedding procedure. These forceps are usually preheated over an open flame. If, however, smaller tissue particles are handled with overheated forceps, arteficial alterations may occur which are apt to hamper or falsify the histologic evaluation of the prepared section. Some typical tissue artefacts due to the handling with overheated forceps, are demonstrated with slides from liver biopsies. Recent experiences with an auxiliary instrument for paraffin embedding (Histostat of Vogel, designed by Ciplea) are reported. The forceps are kept at stable temperatures by immersion in fluid paraffin during the embedding procedure, thus excluding almost completely the risk of tissue artefacts by handling with overheated forceps.

Biopsy↗