Browsing by Author "Radhakrishnan, N S"

Now showing 1 - 5 of 5
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    Diagnostic utility of immunohistochemical techniques in intramedullary Schwann-cell tumours.
    (Indian journal of pathology & microbiology, 1993)
    Histopathologic features in two intramedullary schwann-cell tumours, closely resembled with those of fibrillary astrocytoma and could not be differentiated from each other by the conventional histochemical stains. However application of tumour markers-Glial fibrillary acidic protein (GFAP) and S-100 protein were found to be useful in differentiating these two tumours and thus helped in making an accurate histopathological diagnosis in these two patients.
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    Immunohistochemical demonstration of mycobacterial antigens in intracranial tuberculoma.
    (Indian journal of experimental biology, 1991)
    Mycobacterial antigens have been demonstrated immunohistochemically in the paraffin sections of 10 intracranial tuberculous granulomas and the results were compared with the detection of acid fast bacilli by conventional Ziehl-Neelsen method. In none of the 10 specimens, acid fast bacilli were demonstrated while mycobacterial antigens were characterised as diffusely staining granular brownish-pink material within the cytoplasm of giant cells and macrophages. In 14 specimens of granulomatous lesions due to non-tuberculous aetiology, immunohistochemical stains were negative for mycobacterial antigen. Thus demonstration of mycobacterial antigen will be not only useful in establishing mycobacterial aetiology of a caseating intracranial granuloma but also can be used as an alternative method to the conventional Ziehl-Neelsen method.
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    Mitochondrial myopathies--a clinicopathological study.
    (Indian journal of pathology & microbiology, 1998)
    Mitochondrial myopathies are heterogeneous group of clinical disorders that can affect multiple systems besides skeletal muscles. The mitochondrial abnormalities in the skeletal muscles are morphologically identified by the presence of characteristic Ragged-red fibers (RRF) in the cryostat sections of the muscle stained with modified Gomori's trichrome stain. In this retrospective study, clinical and histopathological features in six patients with mitochondrial myopathies have been analysed. The utility of histochemical methods in confirming the diagnosis of mitochondrial myopathy has been emphasised.
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    Nucleolar organizer regions in pituitary adenomas.
    (Indian journal of pathology & microbiology, 1995)
    In this study, thirty-two non-functional and eighteen functional pituitary adenomas were analysed for the presence of argyrophilic nucleolar organizer regions (Ag-NORs) in paraffin sections, using an one-step silver-colloidal staining method. Differences in the mean Ag-NOR numbers of functional pituitary adenomas were statistically significant than those of non-functional pituitary adenomas. It is being emphasised that evaluation of Ag-NOR count is a more reliable index than the presence of mitotic figures in predicting the proliferative activity as well as possibility of recurrence in a patient with pituitary adenoma.
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    Utility of silver-colloidal staining method in the diagnosis of medulloblastoma.
    (Indian journal of pathology & microbiology, 1994)
    Histopathological features of medulloblastomas are usually distinctive. However in rare instances, a distinction between the neoplastic cells of medulloblastoma and the neurones in the cerebellar internal granular layer becomes difficult at light microscopic level. In order to distinguish presence of argyrophilic Nucleolar Organizer Regions (Ag-NORs) was analysed in the paraffin sections of medulloblastoma as well as in the cerebellar internal granular layer. The neoplastic cells in medulloblastoma contained a mean 4.78 Ag-NOR per nucleus while the neurones in cerebellar internal granular layer contained a mean Ag-NOR 0.90 +/- 0.12 per nucleus. Compound Ag-NORs were present in the cells of medulloblastoma while they were absent in the neurones of cerebellar internal granular layer. The results of this study indicate that Ag-NOR technique may be useful in an uncommon situation, where a histopathological distinction between cells of medulloblastoma and neurones in the cerebellar internal granular layer becomes difficult.