Biomedical subjects

M R Ozercan

Publications and source records attributed to M R Ozercan.

3 recordsLinked to original sources

PubMed1995

A sensitive staining method for NORs.

A sensitive staining method for nucleolar organizer regions (NORs) is described, using blue toning of AgNORs. NORs are loops of DNA which are transcribed into ribosomal RNA. NORs can be demonstrated by staining with silver nitrate, since NOR-associated proteins are argyrophilic, producing structures termed AgNORs. Normal blood lymphocytes were stained with both methods. The number and resolution of NORs increased 2-3 times by blue toning (30 mmol/l FeCl3, 11 mmol/l potassium hexacyanoferrate(III), and 33 mmol/l oxalic acid) compared with silver staining. A significant difference in the number of NORs was noticed between silver-stained and blue-toned cells (P < 0.001). The blue toning technique thus appears to be more sensitive in detecting NORs than the AgNOR method and may prove a useful alternative for applications in histopathology.

Chlorides↗

PubMedDate not supplied

Proliferating cell nuclear antigen and nucleolar organizer region for differential diagnosis of dysplasia and adenocarcinoma in gastric biopsies.

INTRODUCTION: The value of proliferating cell nuclear antigen (PCNA) and nucleolar organizer region (AgNOR) for differential diagnosis of normal mucosa, dysplasia and adenocarcinoma in gastric endoscopic biopsies, and correlation between these two methods were evaluated. METHODS: 15 gastric endoscopic biopsy samples from normal mucosa, 15 from areas of dysplasia and 15 from low grade adenocarcinoma were studied. AgNOR and PCNA immunostaining were applied to paraffin sections. RESULTS: Mean AgNOR value and PCNA-labeling index were the lowest in normal mucosa and the highest in adenocarcinoma. Mean (SD) AgNOR numbers were 2.9 (0.3) in normal mucosa, 5.9 (1.7) in dysplasia and 15.7 (2.8) in adenocarcinoma. PCNA-labeling index was 2.4 (1.1) in normal mucosa, 27.5 (4.6) in dysplasia and 42.1 (5.3) in adenocarcinoma. The differences between normal mucosa and dysplasia, and between dysplasia and adenocarcinoma were significant (p < 0.001). Overlapping values were observed in AgNOR counts between normal mucosa and dysplasia, and in PCNA-labeling indices between dysplasia and adenocarcinoma. No correlation was found between AgNOR and PCNA. CONCLUSION: Though mean AgNOR values and PCNA indices were significantly different between normal mucosa, dysplasia and adenocarcinoma, these could not be used in differential diagnosis because of overlapping values between groups.

Adenocarcinoma↗

PubMedDate not supplied

Nucleolar organizer regions in lymphomas: a quantitative study.

Using a silver staining technique, nucleolar organizer region-associated proteins (Ag-NORs) have been studied in paraffin sections of 76 non-Hodgkin's lymphomas, five normal lymph nodes, and five < > lymph nodes. The mean number of nucleolar organizer regions per nucleus was 1.19 (SD:0.09) for normal lymphocytes, 3.04 (SD:0.14) for reactive lymph nodes, 2.79 (SD:0.44) for low-grade lymphomas, 6.33 (SD:1.58) for intermediate-grade lymphomas, and 10.53 (SD:1.97) for high-grade lymphomas. There were highly significant differences in Ag-NOR counts among the groups (p < 0.001). The Ag-NOR regions were often observed in nuclei in areas where nucleoli themselves were invisible. It is suggested that this method is useful in diagnostic histopathology and in differentiation of the grade of lymphomas.

Humans↗