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D Gambarelli

Publications and source records attributed to D Gambarelli.

At least 55 records · Page 3Linked to original sources
PubMed1992

Central neurocytomas. Critical evaluation of a small-cell neuronal tumor.

We report herein the clinical and pathological features of 20 patients with central neurocytomas. Investigations for various differentiation antigens and cell type-specific markers were performed by immunohistochemistry using paraffin-embedded tissue. In addition, the expression of L1 adhesion molecule and of the various N.CAM (neural cell adhesion molecule) isoforms were investigated by immunoblotting studies in two frozen specimens. Central neurocytomas are clinically characterized by their intraventricular localization, occurrence in young adults, and good prognosis. It rarely occurs in patients over 50, but such cases have a poor prognosis. Total surgical excision is the best treatment. Radiotherapy is appropriate if surgery is incomplete or contraindicated. Histologically, central neurocytomas display the following features: an oligo-like pattern, usually associated with large fibrillary rosettes or perivascular arrangement, and a rich endocrine-type vasculature. Central neurocytomas have a remarkably homogeneous antigenic profile. GFAP expression is only found in scattered reactive astrocytes, S100 protein in reactive astrocytes and rare tumor cells. Among the pan-neuroendocrine markers, central neurocytomas always express neuron-specific enolase; they frequently express synaptophysin but never chromogranin A. Synaptophysin is the most reliable immunohistological marker for central neurocytomas; however, immunoreactivity could be lost with long formalin fixation. In these cases, electron microscopy is used to support the neuronal nature of the tumor cells. The expression of L1 adhesion molecule and the isoform 180 of N.CAM, indicates that central neurocytomas are formed by cells committed to neuronal phenotype. Nevertheless, advanced neuronal differentiation may be absent, as suggested by the persistence of embryonic N.CAM, the nonexpression of neurofilament proteins, and the absence of mature synapses in numerous cases. Central neurocytomas and neuroblastomas share some biochemical properties, but their respective clinicopathological features and biological behavior are dramatically different.

Adolescent↗
PubMed1992

Telomeric association of chromosomes in human meningiomas.

In six cases of meningiomas, a karyotype with monosomy 22 and telomeric associations has been observed. The histopathological and cytogenetic correlations showed that the tumors with these chromosomal abnormalities were of a fibroblastic type and presented a certain degree of anaplasia. The relationship between telomeric association and malignancy is discussed.

Chromosomes, Human↗
PubMed1991

Infratentorial ependymomas of childhood. Correlation between histological features, immunohistological phenotype, silver nucleolar organizer region staining values and post-operative survival in 16 cases.

We have examined pathological criteria in 16 cases of infratentorial ependymomas of childhood using a conventional histological approach, with immunohistochemistry and silver nucleolar organizer region staining (AgNORs). We have found that some of these criteria are of prognostic value. The following histological features were evaluated in each case: cellular density, cellular or nuclear pleiomorphism, mitosis, focal necrosis, endothelial proliferation and complete loss of differentiation. The expression of the following antigens was also studied: epithelial membrane antigen (EMA), human natural killer (HNK1), glial fibrillary acidic protein (GFAP) and vimentin. Only three histological criteria have been retained as indicative of bad prognosis, i.e., high mitotic index, a large amount of necrosis and complete loss of differentiation. These criteria distinguish ependymomas from anaplastic ependymomas. GFAP was expressed in all tumors while other antigens were more variable. In addition tumors expressing large amounts of GFAP were statistically associated with a better prognosis. Increased vimentin expression associated with a decrease of GFAP immunoreactivity correlated with anaplasia and short survival. EMA was not directly correlated with postoperative survival but may be considered as a further prognostic factor. Finally AgNORs values were not statistically correlated with postoperative survival.

Adolescent↗
PubMed1991

Epidemiological study of congenital diaphragmatic defects with special reference to aetiology.

Congenital diaphragmatic defects (CDD) are easily accessible to ultrasonographic diagnosis. In spite of progress in the management of prenatally detected cases, the mortality rate for CDD remains high. The prognosis depends mainly on the severity of fetal lung hypoplasia but is also linked to the associated malformations. We report on 77 cases of CDD ascertained between 1982 and 1988 from 136,161 consecutive births in the Bouches du Rhône area. The spontaneous perinatal mortality rate was 61% with 28 early post-natal deaths and 14 stillbirths. Eight pregnancies were terminated after prenatal diagnosis. The diaphragmatic defect was associated with other congenital anomalies in 33 cases, more often among stillborn (92.8%) than liveborn infants (23.6%). A chromosomal abnormality was present in 9 cases representing 11.6% of all CDD and in 27.2% of cases with other anomalies. A Mendelian disorder was present in 9 cases (eight Fryns syndrome and one Fraser syndrome). This study underlines the necessity of a systematic work up of prenatally diagnosed cases, including fetal karyotyping and analysis of associated malformations in order to adapt the management of the pregnancy and delivery to the prognosis.

Abnormalities, Multiple↗
PubMed1991

Different susceptibilities of the geniculate and extrageniculate visual pathways to human Creutzfeldt-Jakob disease (a combined neurophysiological-neuropathological study).

Flash evoked visual potentials (FEPs) of 7 patients with advanced Creutzfeldt-Jakob disease (CJD) were compared with those recorded in 7 patients with senile dementia of the Alzheimer type (SDAT), in 13 age- and sex-matched healthy volunteers and in 7 neuropsychiatrically normal subjects whose occipital evoked responses were increased in amplitude (amplitude controls). Post-mortem examination was performed in 4 of 7 CJD patients in order to map pathological changes along the visual pathways, including the retino-geniculo-striate and extrageniculate pathways. Normal FEPs were typified by 2 constant early components (P1 and N2) followed by several (3 or more) late components that were characterized by marked interindividual variability. Amplitude controls had enlarged (from 14 to 44.8 microV, mean 25.7) P1 component. Both SDAT and CJD patients had normal early FEP waves (P1 and N2) and important alterations of the late FEP components. Moreover, a late positive component was responsible for abnormally enlarged FEPs (52.6 and 58.2 microV) in 2 CJD patients. Finally, electroretinograms, recorded in 1 CJD patient, were normal. These findings suggested relative functional integrity of the retino-geniculo-striate pathway associated with important dysfunction of the cortical visual processing in both SDAT and CJD patients. Pathological studies disclosed preservation of optic nerves, chiasmas, lateral geniculate nuclei and Gennari's strip of the striate cortex but associated with important spongiform change, neuronal loss and gliosis in the superior colliculi (layer II), pulvinar, extrastriate cortex and layers II-III, V and VI of the striate cortex. We conclude that different visual pathways have different susceptibilities to CJD: important functional and anatomical alterations of the intracortical and extrageniculate pathways contrast with relative preservation of the retino-geniculo-striate pathway.

Adult↗
PubMed1991

Holoprosencephaly-polydactyly ('pseudotrisomy 13') syndrome: a syndrome with features of hydrolethalus and Smith-Lemli-Opitz syndromes. A collaborative multicentre study.

A syndrome of holoprosencephaly and postaxial polydactyly, associated with hydrocephalus, heart defect, adrenal hypoplasia, and other visceral malformations, has been observed in five unrelated children with normal chromosomes. Clinical overlap with lethal acrodysgenital dwarfism (Smith-Lemli-Opitz syndrome type II) and hydrolethalus syndrome is discussed. Recessive inheritance seems likely.

Abnormalities, Multiple↗
PubMed1991

Malignant transformation of an osteoblastoma of the skull: an exceptional occurrence. Case report.

What is apparently the first reported case of spontaneous malignant transformation of a benign osteoblastoma of the skull is described. The initial lesion was completely removed surgically and showed the histological features typical of a benign osteoblastoma. No radiotherapy was performed. Eleven years later the patient developed an osteosarcoma of the skull. Review of the literature showed that malignant transformation of benign osteoblastomas is extremely rare and could take place spontaneously. However, the risk of this occurring seems higher after inadequate initial treatment (curettage or partial excision). Follow-up monitoring of patients with osteoblastoma of the cranial vault is suggested.

Adult↗
PubMed1991

A new approach of brain tumors: the cytogenetic study.

Cytogenetic studies of brain tumors in adults have made it possible to determine specific chromosomal abnormalities and to detect a high incidence of gene amplification related to these abnormalities. Data from the literature and our own results show frequent numerical deviations in glioblastomas, such as gain of chromosome 7, but also 19, 20 and X, loss of certain chromosomes: monosomies 6, 14 and 22. Most of the structural abnormalities are deletions involving the chromosomal regions 1p, 6q, 7q and 9p, and the presence of double-minutes (DMs), the latter being the chromosomal expression of EGFR gene amplification. Cytogenetic analysis of meningiomas has shown that some of them have monosomy 22 alone while others have additional abnormalities. Antioncogenes probably play a part in these tumors. Their identification will explain the neuro-oncogenesis process and perhaps open a new route for the treatment of brain tumors.

Adult↗
PubMed1990

What's new in primary central nervous system lymphomas?

Primary central nervous system lymphomas (CNSL) are uncommon neoplasms accounting for about 1% of primary brain tumors. Patients with congenital or acquired immunodeficiencies including AIDS patients and transplant recipients represent the main high-risk population for CNSL occurrence. An important point emerging from the literature is that CNSL incidence has dramatically increased during the last years not only in HIV infected patients by virtue of the AIDS epidemic spread, but also for unclear reasons in immunologically normal persons. Although c-myc oncogene activation and Epstein-Barr virus infection are considered to play a role in CNSL development, the peculiar tendency of these lymphomas to occur and remain inside the CNS is not well understood and may involve putative CNS binding molecules carried by lymphocytes. The clinical presentation is characterized by a great variety of neurological disorders. Radiological features consist of hyperdense homogeneous deposits within the subcortical white matter with a pattern of marked enhancement after injection of contrast material. The tumor masses are usually ill-defined and multicentric. Although all cytological types can be observed, the most common types belong to the high-grade category of non-Hodgkin's lymphoma. Monoclonal antibodies reactive with formalin-fixed, paraffin-embedded sections can be used in conjunction with stereotactic needle biopsy to provide accurate immunological characterization of CNSL. The large majority of CNSL is of B-cell origin but T-cell lymphomas seem at the present time less exceptional than previously thought. Although radiotherapy and chemotherapy can increase length of survival, the prognosis of CNS remains dramatically poor, the shortest survival being observed in AIDS patients.

Humans↗
PubMed1990

Atypical inflammatory histiocytic tumor of the cerebellum. A histological, immunohistochemical, and ultrastructural study.

We report a primary histiocytic tumor involving the cerebellum. Microscopically, the tumor was composed of nests of pleomorphic cells surrounded by thin vascular septa invaded by lymphocytes. Immunocytochemistry and electron microscopy confirmed the histiocytic origin of the tumor. Although we considered several diagnoses, we ultimately concluded that "atypical inflammatory histiocytic tumor of the cerebellum" best characterized the lesion. This case represents another example of the diversity of histiocytic tumors and shows that they can occur in the central nervous system.

Adult↗
PubMed1990

[Colloid cysts of the third cerebral ventricle. Computed x-ray tomography, MRI and stereotaxic puncture. Apropos of 9 cases].

The authors report their experience with Colloid Cysts of the third ventricle (9 cases treated between 1983 and 1989). Eight of them were punctured using stereotactic approach; five cysts were completely evacuated and the patients are free of recurrence. In three cases, tapping was impossible or the cyst insufficiently evacuated and the patients were secondary operated on (open microsurgical approach). The last case was directly operated on. Colloid cysts cured by stereotactic puncture were all hypo or iso-dense at C.T. scan and had a diameter of more than 1 cm. All these cases have had a M.R.I. exploration and the image of the cyst was always the same increased T1 and T2 signal. Unfortunately, we did not have the opportunity to realize M.R.I. in colloid cysts of a small size and hyperdense at C.T. scan. These results can help to the indication of a stereotactic puncture at the first attempt in some well defined colloid cysts.

Adolescent↗
PubMed1990

Primary intracerebral plasma cell granuloma: a light, immunocytochemical, and ultrastructural study of one case.

A case of primary intracerebral plasma cell granuloma without meningeal attachment is presented. Histologically, the lesion showed two different patterns. At the center, it displayed the features of a benign fibrous histiocytoma. At the periphery, a mixture of polyclonal plasma cells, lymphocytes, and "epithelial-like" cells was observed. Electron microscopy and immunocytochemistry confirmed the histiocytic nature of the "epithelial-like cells." The differential diagnosis and histogenesis of such a lesion are discussed.

Brain Diseases↗
PubMed1989

Fryns syndrome: report on 8 new cases.

The name Fryns syndrome was given to a new variable multiple congenital anomaly syndrome, almost always lethal, described in 1978, and now known to be autosomal recessive. Since that date, 20 patients have been reported in the literature. We describe 8 new cases, 6 of which were diagnosed in a series of 112,276 consecutive births (livebirths and perinatal deaths). The prevalence of this syndrome can be estimated to be around 0.7 per 10,000 births. These new cases confirm that the most frequent anomalies are diaphragmatic defects, lung hypoplasia, cleft lip and palate (often bilateral), cardiac defects (septal defects and aortic arch anomalies), renal cysts (type II, III or IV), urinary tract malformations, and distal limb hypoplasia. Most patients also have hypoplastic external genitalia and anomalies of internal genitalia (bifid or hypoplastic uterus, immature testes). The digestive tract is also often abnormal: duodenal atresia, pyloric hyperplasia, malrotation and common mesentery are present in half of the patients. When the brain was examined, more than half were abnormal (Dandy-Walker anomaly and agenesis of corpus callosum). A few patients demonstrated cloudy cornea. We examined the eyes of three patients histologically: two of them showed retinal dysplasia with rosettes and gliosis of the retina, thickness of posterior capsula of lens and irregularities of the Bowman membrane. Four of our cases were diagnosed prenatally between 24 and 27 weeks. It is to be expected that prenatal diagnosis will be made often and earlier in the future, as the spectrum of anomalies of the Fryns syndrome can easily be evidenced by sonography.

Abnormalities, Multiple↗
PubMed1988

Long-term follow-up after stereotaxic basal ganglia surgery in parkinsonism. A neuroanatomical study of a case showing unusual postural disorders.

A 60-year-old man who had Parkinson's disease for 25 years became unable to maintain the upright position of the trunk while standing or walking. Because of a loss of postural fixation, his trunk sank forward until his back was horizontal. Fifteen years before, a bifocal implantation of radioactive yttrium-90 had been performed by a stereotaxic procedure at the level of the globus pallidus (GP) and the ventrolateral thalamus, respectively on the right side. A second operation, 2 years later, had been made by electrocoagulation in the left ventrolateral thalamus. Postmortem examination showed the following features (a) neuronal cell loss in the pigmented nuclei of the brainstem with intracellular Lewy bodies and gliosis. These data corresponded with the usual pathology of idiopathic Parkinson's disease; (b) surgical lesions resulting from the previous stereotaxic operations in the right GP and the ventrolateral thalamus on both sides and (c) neuronal cell loss without gliosis in the right GP that was evident in regions spared by the surgical lesion. Moreover, these degenerative changes were particularly seen in the left GP, which was surgically unlesioned. The ansa lenticularis was demyelinated on both sides. These data might be consistent with a retrograde degenerative process affecting the pallidothalamic projections. Beside the role of the neuronal cell loss affecting the pars compacta of the substantia nigra (SN) in akinesia, the role of the lesions affecting the G.P. in the genesis of postural disorders is suggested.

Follow-Up Studies↗
PubMed1988

[Extra-medullary intradural melanotic tumor: apropos of a case of dorsal pigmented neurinoma. Review of the literature].

The authors report a case of pigmented thoracic neuroma (T3) discovered in a 40 year old woman on a routine chest x-ray. This hourglass-shaped extra-dural tumour was investigated by computed tomography, nuclear magnetic resonance imaging and iopamiron myelography. Treatment consisted of complete resection by T2-T3 laminectomy and left T3 foraminotomy. Light and electron microscopy revealed melanin secretion by the Schwann cells. A review of the literature confirms the findings observed in our case in terms of the slow clinical course, the benign nature and the excellent prognosis following complete resection, without the need for any radiotherapy or chemotherapy. The various histogenetic theories of extramedullary intra-dural melanotic tumours are reviewed. The difficulties of the differential diagnosis are discussed.

Adult↗
PubMed1987

[Role of phagocytes in experimental scrapie in hamsters].

We studied the interactions between scrapie agent and hamster's phagocytic cells. Macrophages which have been in contact with the scrapie agent are able to carry the infectivity of this agent. We induced variations of different parameters involved on fixation and phagocytosis and we did not observe any modification. A depletion of phagocytic cells induced in hamster at the entry of scrapie increase the incubation time of the illness. Furthermore phagocytic cells cocultured with glial cells seem to be able to transfer infectivity to glial cells. So scrapie agent and hamster's reticulo-endothelial system probably interact at three levels: first at the entry, then during haematogenous diffusion of scrapie agent and finally nearly the central nervous system.

Animals↗