Biochemical Characterization of an Immunoglobulin Lambda I Light Chain Amyloid Protein Isolated From Formalin-Fixed Paraffin-Embedded Tissue Sections

In male dogs, Brucella canis frequently causes epididymitis, ultimately resulting in testicular atrophy and infertility. Although B. canis predominantly affects the epididymis, the misleading term “orchitis” is still commonly used by clinicians. Of additional concern, diagnosis in dogs remains challenging because of variable sensitivity and specificity of serologic assays and fluctuations in bacteremia levels in infected dogs, reducing the sensitivity of blood culture. We describe here the histologic lesions in the scrotal contents of 8 dogs suspected of being infected with B. canis and clinically diagnosed with orchitis. We explored the possibility of using immunohistochemistry (IHC) and real-time PCR (rtPCR) in formalin-fixed, paraffin-embedded (FFPE) tissues to detect the presence of B. canis. Epididymitis of variable chronicity was identified in all 8 dogs, with only 3 also exhibiting orchitis. Using rtPCR, the presence of B. canis was identified in 4 of 8 dogs, with 3 of these 4 dogs also positive by IHC. These results suggest that rtPCR and IHC are promising techniques that can be used in FFPE tissues to detect B. canis when other detection techniques are unavailable. Additionally, accurate recognition of epididymitis rather than orchitis in suspect cases could aid in accurate diagnosis.

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Discrimination of Aspergillosis, Mucormycosis, Fusariosis, and Scedosporiosis in Formalin-Fixed Paraffin-Embedded Tissue Specimens by Use of Multiple Real-Time Quantitative PCR Assays

Journal of Clinical Microbiology ◽

10.1128/jcm.01185-16 ◽

2016 ◽

Vol 54 (11) ◽

pp. 2798-2803 ◽

Cited By ~ 35

Author(s):

Elham Salehi ◽

Mohammad T. Hedayati ◽

Jan Zoll ◽

Haleh Rafati ◽

Maryam Ghasemi ◽

...

Keyword(s):

Fusarium Oxysporum ◽

Aspergillus Flavus ◽

Ffpe Tissue ◽

Content Type ◽

Real Time Quantitative Pcr ◽

Tissue Sections ◽

Formalin Fixed Paraffin ◽

Formalin Fixed Paraffin Embedded ◽

Tissue Specimens ◽

Formalin Fixed

In a retrospective multicenter study, 102 formalin-fixed paraffin-embedded (FFPE) tissue specimens with histopathology results were tested. Two 4- to 5-μm FFPE tissue sections from each specimen were digested with proteinase K, followed by automated nucleic acid extraction. Multiple real-time quantitative PCR (qPCR) assays targeting the internal transcribed spacer 2 (ITS2) region of ribosomal DNA, using fluorescently labeled primers, was performed to identify clinically important genera and species of Aspergillus , Fusarium , Scedosporium , and the Mucormycetes . The molecular identification was correlated with results from histological examination. One of the main findings of our study was the high sensitivity of the automated DNA extraction method, which was estimated to be 94%. The qPCR procedure that was evaluated identified a range of fungal genera/species, including Aspergillus fumigatus , Aspergillus flavus , Aspergillus terreus , Aspergillus niger , Fusarium oxysporum , Fusarium solani , Scedosporium apiospermum , Rhizopus oryzae , Rhizopus microsporus , Mucor spp., and Syncephalastrum . Fusarium oxysporum and F. solani DNA was amplified from five specimens from patients initially diagnosed by histopathology as having aspergillosis. Aspergillus flavus , S. apiospermum , and Syncephalastrum were detected from histopathological mucormycosis samples. In addition, examination of four samples from patients suspected of having concomitant aspergillosis and mucormycosis infections resulted in the identification of two A. flavus isolates, one Mucor isolate, and only one sample having both R. oryzae and A. flavus . Our results indicate that histopathological features of molds may be easily confused in tissue sections. The qPCR assay used in this study is a reliable tool for the rapid and accurate identification of fungal pathogens to the genus and species levels directly from FFPE tissues.

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Quantitative radioimmunohistochemical measurements of p185(erbB-2) in frozen tissue sections.

Journal of Histochemistry & Cytochemistry ◽

10.1177/44.11.8918900 ◽

1996 ◽

Vol 44 (11) ◽

pp. 1251-1259 ◽

Cited By ~ 12

Author(s):

J R Reeves ◽

J J Going ◽

G Smith ◽

T G Cooke ◽

B W Ozanne ◽

...

Keyword(s):

Tumor Biology ◽

Breast Carcinomas ◽

Tissue Sections ◽

Biopsy Specimens ◽

Formalin Fixed Paraffin ◽

Formalin Fixed Paraffin Embedded ◽

Interstudy Variability ◽

High Degree ◽

The Relationship ◽

Formalin Fixed

The relationship between expression of the c-erbB-2 proto-oncogene and the biology of breast cancer has been investigated widely, most studies using immunohistochemistry in formalin-fixed, paraffin-embedded tissues. This technique is at best semiquantitative and there is a high degree of interstudy variability because of its subjective nature and poor methodological standardization. The relationship between the levels of expression and biology can be examined thoroughly only with an accurately quantitative technique. We have developed a radioimmunohistochemical assay to measure p185(erbB-2) in tissue biopsy specimens. The method involves incubating frozen sections with 125I-labeled monoclonal antibody, microautoradiograpy, and grain counting with image analysis. Sections of cell pellets with known c-erbB-2 levels are processed with each batch of samples as internal calibration standards. We have quantified c-erbB-2 expression in 60 breast carcinomas and compared the results with conventional immunohistochemistry. Radioimmunohistochemistry measured receptor levels throughout the range of expression in breast carcinomas, whereas conventional immunohistochemistry detected the protein only in the highest expressing tumors. The quantitative, objective data produced by radioimmunohistochemistry allow a more thorough evaluation of the relationship between c-erbB-2 expression and tumor biology. This technique may have applications in other fields where quantitative data is required and relevant monoclonal antibodies are available.

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