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Biomedical subjects

Y Collan

Publications and source records attributed to Y Collan.

At least 217 records · Page 12Linked to original sources

Value of electron microscopy in kidney biopsy diagnosis.

Kidney biopsy reports given during 2003 were collected from the authors' pathology database. A total of 111 biopsies were performed. Five tumor samples were not studied with electron microscopy (EM). Of the remaining 106 biopsies, 85 were studied with EM. EM was not performed in 10/24 transplant biopsies, or in 11/82 cases of suspected primary kidney disease. The role of EM was evaluated by grouping the samples in 3 categories: (1) EM was essential for diagnosis, (2) EM contributed to the interpretation and cleared uncertainties, and (3) EM had no influence on the diagnostic process. In transplant biopsies EM influenced the final diagnosis in 86% of cases (category 2). In biopsies performed for primary kidney disease EM was essential for diagnosis in 18.3% clearly contributed in 53.5%, and had no influence on the final diagnosis in 28.2% of cases. The study suggests that the importance of EM has not decreased during the last few years. Because only about 25% of the EM reports did not have any influence on the diagnostic process, it is recommended that kidney biopsy protocols should include EM in all biopsy cases, or at least tissue should be reserved for EM studies of all cases. Because of the influence of EM on the diagnostic process the need for EM in pathology training should be emphasized.

Adult↗

Viral culture and electron microscopy of ganglion cells in Meniere's disease and Bell's palsy.

Specimens of Scarpa's ganglion during vestibular neurectomy were obtained in 6 cases of Meniere's disease and specimens of geniculate ganglion in 2 cases of total facial nerve decompression and studied by tissue culture methods for detection of possible herpes and cytomegalovirus infection. In electron microscopy inclusions in the form of interwoven yarn-like structures, coarse aggregates of chromatin and light nuclear bodies were found in several vestibular ganglion cells. No typical herpes virus virions could be demonstrated. The culture for viruses all proved finally negative. At present there is no proof that viruses are present in Scarpa's or geniculate ganglions but the possibility remains that the inclusion bodies observed might be viruses inactivated inside the ganglion cells.

Cell Nucleus↗

Artifacts in eighth cranial nerve biopsy.

The occurrence of artifactual morphological changes was investigated in human eighth nerve biopsies and corresponding changes were brought about in biopsies from rats by mechanical handling before fixation. At the very site of compression by a pair of forceps the biopsy stained lighter than in its immediate surroundings. Electron microscopy showed denuded and fragmented axons among vesicular debris in the area. Further away the myelin coats were greatly thickened, often to the degree that the axonal canal could no longer be identified. The myelin lamellae showed separation and were occasionally seen in convoluted forms. Also variations in the diameters of the nerve fibres and ruptures of the meylin coats could be produced after mechanical handling.

Animals↗

Interpretation guidelines of DNA histograms from tissue sections of breast cancer.

BACKGROUND: Evaluation of nuclear DNA staining intensity from histological breast cancer sections has not always been accepted, because of the difficulties in interpreting the histograms. One reason for this is the lack of evidence based interpretation guidelines. MATERIALS AND METHODS: The DNA staining intensity of 140 breast cancer samples was measured with flow cytometry (FCM) and image cytometry (ICM). The methods were compared by using grading efficiency (GE). RESULT: First, the ICM histograms were evaluated with a computer assisted image cytometry system using different cut off points for aneuploidy. The GE results varied from 67.9-76.4%. Subjective interpretation and evaluation according two previously published interpretation methods did not improve the GE. Secondly, we excluded histograms which showed clearly different cell clones in FCM and ICM. The GE of remaining histograms was 77.9%. Comparison of these histograms allowed formulation of interpretation guidelines which improved the GE to 85.3%. CONCLUSIONS: This study suggests that efficient interpretation guidelines of section-based DNA histograms can be created.

Aneuploidy↗

DNA cytometry in diagnostic cytology of the prostate gland.

BACKGROUND: Differential analysis and cytological grouping of fine needle aspiration biopsy (FNAB) samples of the prostate are important in practice. We used image analytical DNA cytometry to achieve this and also studied the best method of interpretation of the histograms. MATERIALS AND METHODS: Sixty-two FNAB samples of the prostate were stained with Feulgen stain and nuclear DNA histograms were produced by image cytometry. The most atypical cell groups were selected for measurements. Also, free epithelial cells between cell groups were studied. The cells presented in the histograms were grouped according to the nuclear DNA content and by application of different gates of observation for diploid status. RESULTS: Several DNA histogram features (histogram classification categories, benign and malignant histogram patterns, presence of >5c-7c cells) showed significant relationships to differential diagnosis. Highly aneuploid (>5c-7c) cells had the potential for distinguishing a progressive-type of prostate cancer. CONCLUSION: The fraction of tetraploid and aneuploid histograms increased from atypical but benign to definitely malignant samples. DNA histograms have potential in the differential diagnosis and evaluation of the progressive character of prostate cancer.

Biopsy, Needle↗

Breast cancer in Nigeria and Finland: epidemiological, clinical and histological comparison.

BACKGROUND: We compared the histology and patterns of occurrence of breast cancers in Nigeria (n = 297) and Finland (n = 285). PATIENTS AND METHODS: The histology of invasive ductal carcinoma (IDC) was re-evaluated using similar criteria. The clinical data were extracted from medical records. RESULTS: The mean age at presentation was 42.7 (12.2) years in Nigeria vs. 58.7 (12.5) years in Finland. In both populations there was an association between reproductive factors and the occurrence of breast cancer. In Nigeria, 53.2% of cases belonged to stages 3 and 4 (vs. 6.7% in Finland). In Finland there were higher frequencies of lobular, tubular and mucinous types than in Nigeria. The Nigerian material had more medullary type (2.7% vs. 0.7% in Finland), extensive necrosis, nuclear atypia and pleomorphism, with coexisting pleomorphic ductal carcinoma in situ. At 2 years after treatment, the survival figures for Nigeria and Finland were 72.8% and 96.4%, respectively. CONCLUSION: The histology of Nigerian and Finnish cancers clearly differ. Nigerian cancers appear more advanced with higher grade. The atypical in situ component is clearly more common in Nigeria. Part of the differences can be explained by diagnostic and treatment delays associated with misguided socio-cultural beliefs, poor health care access and impaired immunity.

Adolescent↗

Volume corrected mitotic index (M/V index), mitotic activity index (MAI), and histological grading in breast cancer.

A prospective study on breast cancer was started in 1975, and ended in 1987 allowing a mean follow-up of 12.4 years. At the operation tumor size was registered, and after axillary evacuation axillary status was defined histologically. In 1989-1990 volume corrected mitotic index (M/V index), and mitotic activity index (MAI) were estimated, and histological grading performed from archival paraffin sections. In univariate survival analysis axillary node status (p less than 0.0001), M/V index (p less than 0.0001), MAI (p = 0.0001), and tumor size (p = 0.0009), histological grade (p = 0.0195), and irregularity of nuclei (p = 0.0167) predicted survival, recurrence free survival, and breast cancer survival. In a multivariate survival analysis axillary node status, M/V index, tumor size and tubular growth pattern showed independent prognostic value in the order of significance. In the separate analysis of infiltrative ductal or lobular carcinomas the M/V index was the most important prognosticator. The results suggest that the M/V index is more powerful in predicting survival than the mitotic activity index (MAI) in breast cancer. Obviously this is due to better control of variation factors associated with field size and area of epithelium by the M/V index.

Axilla↗