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L Chimelli

Publications and source records attributed to L Chimelli.

59 records · Page 4Linked to original sources
PubMed1984

Granular cell tumor of the fifth cranial nerve: further evidence for Schwann cell origin.

Granular cell tumors arising from the cranial nerves are rare. We describe a granular cell neoplasm of the fifth cranial nerve in a 66-year-old male. Light microscopic appearances included rows and clusters of cells with small peripheral nuclei and abundant eosinophilic cytoplasm. Ultrastructurally the cytoplasm of these cells contained numerous dense bodies, multivesicular bodies and vacuoles. In some areas tumor cells were intermingled with myelinated and unmyelinated nerve fibers showing the same relationships as do Schwann cells and nerve fibers. The association between tumor cells and axon seen in this case lends further support to the putative Schwann cell origin of this neoplasm.

Aged↗
PubMedDate not supplied

Autonomic dysfunction in Chagas disease: lack of participation of the vagus nerve.

To evaluate the possible role of the vagus nerve in the development of the dysautonomia in Chagas disease, we examined 18 nerves from chagasic patients and 8 from non-chagasic patients, autopsied at the Department of Pathology, Ribeirão Preto School of Medicine, Brazil. Histological analysis showed mild inflammatory infiltrate composed predominantly of T lymphocytes, in epi-, peri- and endoneurium. No parasites were observed. Semithin sections showed swollen unmyelinated fibres, occasional thinly myelinated fibres, degenerated and atrophic axons, related to myelinated fibres. These findings were confirmed by electron microscopy, and in teased fibres. The changes were observed both in chagasic and in non-chagasic patients. Statistical analysis of the morphometric findings (myelinated fibre density, axonal and fibre diameters) failed to show significant differences between the 2 groups. The frequency of myelinated fibres of various diameters was also similar in the 2 groups. The morphological and morphometrical findings in chagasic patients are mild, non-specific, and could be related to the age of the patients, or with artefacts, since they have also been observed in non-chagasic patients. Retrograde changes due to the ganglionic lesions in the innervated organs cannot be completely ruled out. Our results do not allow us to implicate the vagus nerve in the dysautonomia in Chagas disease.

Age Distribution↗
PubMedDate not supplied

[The neuropathology of the acquired immunodeficiency syndrome (AIDS)].

The nervous system is frequently involved in patients with AIDS. The lesions can be due to the human immunodeficiency virus (HIV), to opportunistic agents, to the development of tumours, and to occasional nonspecific factors, such as circulatory, metabolic and degenerative changes. The changes directly related to the presence of the HIV include the HIV encephalitis and leucoencephalopathy, the diffuse polydystrophy and the vacuolar myelopathy. The pathogenesis of these lesions is not yet completely clear. Macrophages are the main cells infected by the HIV, and it seems that the cytotoxic effects on the nervous tissue are indirect, may be due to the release of substances by infected macrophages. Among the opportunistic infections, the most frequent is toxoplasmosis followed by cryptococcosis and cytomegalovirus infection, with some differences in series from various countries. Many other agents have been observed in the brain of patients with AIDS. B-cell lymphoma is the most frequent tumour found in the brain and it is not uncommon the association of infections and/or tumours.

AIDS Dementia Complex↗
PubMedDate not supplied

Dengue: neuropathological findings in 5 fatal cases from Brazil.

Neuropathological examination of 5 patients with dengue who died of shock in Rio de Janeiro during an outbreak in summer 1987, showed nonspecific lesions (edema, vascular congestion, hemorrhagic foci and perivascular lymphocytic infiltrates). In one case with delayed marked neurological symptoms, several foci of perivenous demyelination were observed. Neurological manifestations are various and not uncommon in dengue, but their anatomical substratum is not known. An immunopathological mechanism has been postulated in some cases but has never been demonstrated morphologically. The perivenous leukoencephalitis observed in one of our cases could represent the morphological substratum of such an immunological mechanism.

Adolescent↗