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Biomedical subjects

F Giangaspero

Publications and source records attributed to F Giangaspero.

At least 91 records · Page 5Linked to original sources
PubMed1983

The spatio-temporal pattern of the axonopathy associated with the neurotoxicity of 3,4-dimethyl-2,5-hexanedione in the rat.

The neurotoxicity of the gamma-diketone 3,4-dimethyl-2,5-hexanedione(DMHD) was studied to determine the distribution of the neuropathologic changes and the temporal sequence during the intoxication period and following five and 15 weeks of recovery. Intoxication with 3,4-dimethyl-2,5-hexanedione at a daily dose of 0.25 mmoles/kg led to a profound clinical neuropathy, resulting in paralysis of all four limbs after 12-15 days. The cumulative toxic dose for this gamma-diketone was 3-4 mmoles/kg, indicating that dimethyl substitution increased the neurotoxicity of gamma-diketones by a factor of 20-30. The neuropathy was characterized histologically by giant axonal swellings in the proximal axon of the lower motor neuron in a distribution similar to IDPN (beta,beta'-iminodipropionitrile)-neuropathy, with swellings in the anterior horn, intraspinal anterior root, and the proximal anterior root. These swellings developed from six to 12 days of intoxication and were still evident after 15 weeks of recovery. The fact that dimethyl substitution of 2,5-hexanedione accelerated the neuropathy and was characterized by proximal axonal swellings has two important implications: 1) that formation of pyrrole derivatives may be an important step in the pathogenesis of gamma-diketone neuropathies, and 2) that the neurofilament neuropathies may represent a continuum of toxic neuropathies in which the rate of action of the neurotoxin ultimately determines the proximo-distal location of the axonal swellings.

Animals↗
PubMed1983

Computerized tomographic and pathologic studies of the untreated, quiescent, and recurrent glioblastoma multiforme.

Pathological findings in 20 cases of glioblastoma multiforme were correlated with clinical histories and computerized tomographic (CT) scans. This was done to define the neoplasm in three stages: before treatment, during remission, and during recurrence. The untreated lesions were markedly cellular neoplasms composed predominantly of small anaplastic cells. The radiographic central region of low density was necrosis, the enhancing rim was a cellular zone of viable neoplasm, and the perilesional low-density area was edema with infiltrating tumor. In these 20 cases, all of the identifiable neoplasms lay within the zone of peritumoral edema or contrast enhancement, although small anaplastic cells may have been present in more distant regions. The lesions in remission were remarkable for their minimal mass effect, discrete nature, extensive necrosis, and content of large bizarre glia. The large cells were confined to the original tumor bed and were consistent with neoplastic cells inactivated and immobilized by radio- and chemotherapy. These lesions were accurately localized by CT scanning. The recurrent lesions were heterogeneous, but most were formed of widely disseminated small anaplastic cells. The highly cellular regions of such lesions could be localized by CT scanning, but CT could not detect less cellular foci in the cerebrum, cerebellum, or brain stem. In one patient, the contrast-enhancing lesions of "recurrence," were foci of radionecrosis, underscoring the difficulty in distinguishing this entity from recurrent neoplasm.

Adult↗
PubMed1981

Sarcomatous variant of Wilms' tumor. A light and immunohistochemical study of four cases.

Four cases of infantile sarcomatous renal tumors are reported. Rhabdomyoblastic differentiation was investigated in these tumors by the immunoperoxidase method using antimyoglobin sera. Rhabdomyoblastic cells were found in 2 cases and in a metastasis of one case in which the primary tumor was composed by undifferentiated cells negative for myoglobin stain. The histogenesis of these neoplasias is discussed, and it is suggested that they are a sarcomatous variant of Wilms' tumor.

Child, Preschool↗
PubMed1978

Primary oat-cell carcinoma of the larynx.

A primary oat-cell carcinoma of the larynx in a 63-year-old man is reported. The oat-cell pattern appeared intermingled at one edge with a squamous carcinoma. The origin of this mixed tumour is considered together with the literature of extrapulmonary carcinomas having an oat-cell pattern.

Carcinoma, Small Cell↗
PubMedDate not supplied

Pituicytoma: ultrastructural evidence of a possible origin from folliculo-stellate cells of the adenohypophysis.

Pituicytoma is a rare neoplasm occurring in the sellar and suprasellar regions. The tumor is currently considered to arise from the pituicyte, a specialized glial cell of the posterior lobe and the stalk of the pituitary gland. The authors describe a case of pituicytoma, focusing on the ultrastructural features. The patient was a 79-year-old woman with hypopituitarism and visual disturbances. Immunohistochemically, the tumor showed strong and diffuse positivity for vimentin, and EMA and GFAP were focally detectable. Ultrastructurally, the lesion was composed of elongated cells containing in the Golgi area aggregates of intermediate filaments in a concentric pathway (fibrous body), and secretory granules. These features intermediate between a pituicytoma and a pituitary adenoma suggest that "pituicytomas" may also arise from the specialized stromal folliculo-stellate cells of the adenohypophysis, which are able to differentiate into endocrine cells.

Aged↗
PubMedDate not supplied

Mucin-secreting cellular ependymoma: a light and electron microscopy study.

Mucin accumulation in ependymomas is thought to be limited to the myxopapillary variant and represents an important diagnostic feature. Similarly, signet-ring cells in ependymomas have been shown by electron microscopy to represent microrosette instead of mucin secretion. This study describes an infratentorial ependymoma largely composed of mucinous areas and signet-ring cells. The ependymal nature of mucin-secreting cells was confirmed by ultrastructural analysis. This case widens the variable spectrum of ependymal morphology. The value of electron microscopy in differentiating central nervous system neoplasms showing mucous secretion is stressed.

Biomarkers, Tumor↗
PubMedDate not supplied

Littoral cell angioma of the spleen: an additional report of four cases with emphasis on the association with visceral organ cancers.

AIMS AND BACKGROUND: Littoral cell angioma (LCA) is an uncommon vascular tumor of the spleen recently described and interpreted as the tumoral counterpart of the normally present littoral cells lining the splenic sinus channels of red pulp. The diagnosis of LCA is suggested by a quite characteristic morphology and confirmed by the demonstration of a hybrid endothelial/histiocytic phenotype. METHODS: Four original and previously unreported cases of LCA are presented. All four splenic vascular tumors were investigated by light microscopy and immunohistochemistry for endothelial and histiocytic markers. RESULTS: All four cases were associated with visceral epithelial malignancies (colorectal adenocarcinoma in two cases, renal and pancreatic adenocarcinoma in one case each). One case was also associated with an intracranial tentorial meningioma. CONCLUSIONS: We consider our findings as a novelty and signal the possible existence of a clinical syndrome. Five of a total of 21 previously reported cases in the literature were also described as being associated with other cancers (non-Hodgkin's lymphoma in two cases, two not further specified tumors of the liver and brain, an epithelial ovarian cancer, and a non-small cell lung cancer in one case each). Close follow-up and careful investigation in search of a second visceral neoplasm are strongly recommended in cases of LCA, but further clinical observations and more in-depth genetic and molecular studies are needed before any valid conclusions can be drawn.

Aged↗
PubMedDate not supplied

Ultrastructural characterization of oligodendroglial-like cells in central nervous system tumors.

Cells with uniform, small-round nucleus and clear cytoplasm (oligodendroglial-like cell, OLC) are commonly observed in central nervous system (CNS) neoplasm of glial and neuronal lineage, such as oligodendroglioma, clear-cell ependymoma, and central neurocytoma. Immunohistochemistry does not always contribute to the characterization of OLC because of (1) loss of antigen expression; (2) lack of specific markers for oligodendrogliomas; and (3) occasional coexpression of neuronal and glial antigens. An ultrastructural analysis associated with an immunohistochemical study of 20 cases of CNS tumors largely constituted by OLCs has been performed. Neurocytomas (12 cases), medullocytomas (2 cases), cerebral neuroblastoma (1 case), and ganglioglioma (1 case) showed OLCs with ultrastructural features of neuronal differentiation (neuritic processes, dense-core granules, synaptic structures). Oligodendroglioma (3 cases) OLCs were characterized by mitochondrial-rich cytoplasm, and ependymoma (1 case) OLCs showed microrosettes and scattered cilia. The electron microscopic analysis can provide a more precise diagnosis of these OLC-containing tumors despite their uniform morphological appearance.

Adult↗
PubMedDate not supplied

Large-cell medulloblastoma with arrestin-like protein expression.

We report a case of a cerebellar large-cell medulloblastoma in a 12-year-old patient. Despite a gross-total resection followed by a radiation therapy and then a chemotherapy, the death occurred 6 months later. The cyogenetic analysis showed an isochromosome 17q. Immunoreactivity for synaptophysin, neurofilaments, chromogranin and arrestin-like proteins was detected, whereas rhodopsin, vimentin, EMA and PAX-6 were negative. In this study, we demonstrate that large-cell medulloblastoma with translocation in chromosome 17q is a neuronal differentiated medulloblastoma with non-photoreceptor characterization. By reverse transcription and polymerase chain reaction (RT-PCR) method, using primers for beta1, beta2 and visual arrestin, we demonstrate corresponding mRNA for beta1, beta2 arrestin but not for visual arrestin. These results suggest that arrestin immunoreactivity in this tumor corresponds to non-visual arrestin. This case corresponds to a new entity of large-cell medulloblastoma. The potential role of a new marker linked to a beta2 adrenergic receptor needs further molecular characterization to be useful.

Arrestin↗
PubMedDate not supplied

Recurrent and atypical meningiomas--a multiparametric study using Ki67 labelling index, AgNOR and DNA Feulgen staining.

OBJECTIVE: Histological analysis has limited value to predict the biological behavior of meningiomas. In this study, we investigated the utility of indicators of cell proliferation in the evaluation of histologically benign meningiomas. MATERIALS AND METHODS: For this purpose, 50 meningothelial meningiomas, 50 atypical meningiomas and 8 primary benign meningiomas with their recurrences were studied. For each case the Ki67 labeling index (LI), DNA ploidy and AgNOR were evaluated and the results quantitatively processed and assessed by computerized image analyzer. RESULTS: The Ki67 labelling showed a low index (11.3%) in typical meningiomas and primary meningiomas (13.6%). In contrast, it was higher in atypical (26.6%) and recurrent meningiomas (28%). Similar results were obtained for the AgNOR granule count which showed that typical and primary meningiomas had mean 1.51 - 1.49, whereas recurring meningiomas and atypical meningiomas had mean values of 1.92 and 1.98, respectively. DNA ploidy revealed in the hyperpolyploid region between 4c - 16c: 7.02% of the nuclei in primary meningiomas, 17.98% of the nuclei in recurring meningiomas and 24.63% of the nuclei in atypical meningiomas. CONCLUSION: Our results suggest that evaluation of cell proliferation using Ki67 LI, DNA ploidy and AgNOr, integrated with standard histopathology, can provide better information for a correct grading of meningiomas.

Cell Division↗
PubMedDate not supplied

Tubular adenoma of choroid plexus: a case report.

A case of choroid plexus neoplasm histologically composed of tubular structures lined by a layer of cuboidal epithelium is reported. The neoplasm was located in the fourth ventricle of a 26-year-old man. The intense positivity for antisera anti-vimentin, anti-cytokeratin, anti-EMA and anti-S100 protein exhibited by these cells was consistent with choroid plexus origin. The patient is alive and in good health 5 years after surgery. The lesion represents a benign choroid plexus neoplasm not previously reported. The name "tubular adenoma of choroid plexus" is suggested for this variant.

Adenoma↗
PubMedDate not supplied

Brain stem encephalitis in a patient with gastroduodenal and cardiovascular dysfunction: a case report.

The authors describe a case of a 38-year-old woman suffering from long-standing epigastric pain, abdominal fullness and vomiting due to functional alteration of gastroduodenal motility. Following a surgical procedure, a supraventricular tachyarrhythmia and hemodynamic disturbances suddenly appeared and led to death in a few hours. A histopathological study carried out on the brain stem revealed inflammatory lesions suggestive of a viral infection, whereas the study of the conduction system of the heart did not show any alterations. A clinicopathological correlation is suggested between the clinical picture and anatomical lesions of the tegmental region.

Adult↗