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P Mennonna

Publications and source records attributed to P Mennonna.

At least 19 recordsLinked to original sources
PubMed2005

Atypical onset of antiphospholipid syndrome in pregnancy: a case report.

BACKGROUND: We present a case of an atypical onset of antiphospholipid syndrome (APS). CASE: A woman in her 15th week gestation had a thrombosis of an unknown cerebral cavernoma, which was successfully removed. Twenty-six days after, she was admitted for a severe pain in right hypochondrium and a second class HELLP syndrome was diagnosed. Two days after, she had a fetal loss. After 1 month, laboratory tests revealed high level of antiphospholipid antibodies. At the same time, she developed a spontaneous thrombosis at her right arm. After 6 weeks, antiphospholipid antibodies, tested again, result positive. CONCLUSION: Antiphospholipid antibodies often cause pregnancy complications, but, to our knowledge, this is the first report of an association of antiphospholipid antibodies, with cerebral cavernoma thrombosis and early onset HELLP syndrome.

Abortion, Spontaneous↗
PubMed2005

Oligodendrogliomas lacking O6-methylguanine-DNA-methyltransferase expression.

O6-Methylguanine-DNA-Methyltransferase (MGMT) is a DNA repair protein considered to be a chemosensitivity predictor. We evaluated the immunohistochemical MGMT expression in 28 consecutive oligodendroglial tumors (21 oligodendrogliomas, 5 mixed oligoastrocytomas, and 2 glioblastomas with prominent oligodendroglial features; 13 treated with CCNU) and compared it with that of 13 glioblastomas. Twenty-six (93%) oligodendroglial tumors were MGMT-negative, 2 (7%) were MGMT-positive. Twelve (92%) patients treated with CCNU had MGMT-negative lesions and their median survival was 73 months; 1 patient had an MGMT-positive oligodendroglioma and is alive at 28 months. Three (23%) glioblastomas were MGMT-negative and 10 (77%) MGMT-positive. The lower MGMT expression in oligodendroglial tumors compared to glioblastomas (P < 0.05), which have different chemosensitivity, suggests a possible role of MGMT in the determination of chemoresistance. Nevertheless, the heterogeneous outcome of our MGMT-negative oligodendroglial tumors treated with CCNU, indicates that MGMT expression alone is insufficient to predict the response to alkylating drugs, presumably because of the numerous mechanisms involved.

Adult↗
PubMed2004

Results of surgical and endovascular treatment of intracranial micro-arteriovenous malformations with emphasis on superselective angiography.

BACKGROUND: The authors retrospectively reviewed the results of two different treatment modalities (surgery and endovascular approach) in patients with intracranial micro-arteriovenous malformations (micro-AVMs). The goal of this study is to evaluate the respective role of surgical treatment and superselective acrylic embolization in the management of micro-AVMs. METHOD: Fourteen patients with micro-AVMs who had been treated by surgical resection or endovascular acrylic embolization during a 6-year period were analyzed. The average age at presentation was 44.6 years (range, 24-65 yr) with no sex dominance. All patients presented with an intracranial haemorrhage, which was superficial in twelve patients and in eloquent brain areas in seven patients. Severe neurological deficits were observed in eleven patients. FINDINGS: Digital subtraction angiography (DSA) demonstrated micro-AVMs in eleven patients (78.5%) while in three patients (21.5%) the micro-AVM was detected only by superselective angiography (SA). Eight patients underwent surgical intervention which led to definitive resection in seven with no peri-operative morbidity. SA was performed in nine patients and followed by successful acrylic embolization of the micro-AVM in seven with haemorrhagic complications in two patients. All fourteen lesions were completely obliterated as demonstrated angiographically. Outcomes were classified according to the Modified Rankin Scale. With a mean long term clinical follow-up of 33 months (range, 8-75 mo), seven patients were Grade 0, six patients were Grade I and one patient was Grade IV. CONCLUSIONS: SA is deemed necessary to visualize micro-AVMs in case of questionable or negative findings also at delayed DSA in young healthy patients with otherwise unexplained intracranial haemorrhage. Obliteration of micro-AVM can be accomplished either surgically or endovascularly; however, the endovascular approach is associated with a defined procedural risk for haemorrhagic complications and long term angiographic follow-up is necessary.

Adult↗
PubMed2004

Pregnancy and subarachnoid hemorrhage: a case report.

Cerebrovascular diseases are rare in pregnancy and mostly caused by rupture of an arterial aneurysm. We present the case of a pregnant woman at 36 weeks of gestation who had a subarachnoid hemorrhage resulting from rupture of an unknown aneurysm, and who underwent a Cesarean section and an endovascular treatment to embolize the aneurysm.

Adult↗
PubMed2004

[BCL-2 in primary central nervous system lymphomas. Immunohistochemistry and molecular biology].

BCL-2 is a membrane protein known to be an apoptosis inhibitor. It is the product of the bcl-2 gene located on chromosome 18. Several different tumors show BCL-2 over-expression as result of a translocation or independently from it. More than 85% of follicular lymphomas and a smaller number of diffuse large cell B lymphomas contain t(14;18) (q32;q21). The aim of this study was to investigate the immunohistochemical expression of the BCL-2 protein and to ascertain, by means of traditional PCR (Polimerase Chain Reaction), its possible dependence from t(14;18) (q32;q21) in 9 primary central nervous system lymphomas. Six cases (67%) shoved immunohistochemical BCL-2 over-expression and 3 cases (33%) had t(14;18). Precisely: 2 cases (22%) had immunohistochemical BCL-2 over-expression and t(14;18) (q32;q21); 4 cases (44%) had BCL-2 over-expression without translocation; 1 case (11%) did not show diffuse BCL-2 over-expression in presence of the traslocation; the remaining 2 cases (22%) did not demonstrate BCL-2 over-expression or t(14;18) (q32;q21). In conclusion, our results indicate primary central nervous system lymphomas frequently show BCL-2 over-expression that in some case may be related to t(14;18) (q32;q21). Nevertheless, t(14;18) (q32;q21), as evaluated by traditional PCR, may not correspond to diffuse immunohistochemical BCL-2 positivity.

Adult↗
PubMed2003

[Atypical, aplastic, and unusual meningiomas. Morphology and incidence in 300 consecutive cases].

We morphologically studied 300 consecutive and primitive meningiomas surgically treated between march 1997 and april 2002 in order to evaluate the incidence of atypical, anaplastic, and morphologically unusual meningiomas. Two hundred and fifty-five meningiomas (85%) were WHO I, 33 (11%) were WHO II, 9 (3%) were WHO III; the remaining 3 meningiomas (1%) showed clear and diffuse oncocytic differentiation without cytologic or architectural atypia (oncocytic meningiomas). Forty-five of 255 WHO I meningiomas (18%) were infrequent histological subtypes: 18 (7%) psammomatous, 9 (4%) metaplastic, 9 (4%) secretory, 6 (2%) angiomatous, and 3 (1%) microcystic. Thirty of 33 WHO II meningiomas (91%) were atypical, 2 (6%) were clear cell meningiomas, and 1 (3%) was chordoid meningioma. Seven of 9 WHO III meningiomas (78%) were anaplastic and 2 (22%) were papillary. We evidenced the high morphological variability and the discrete occurrence of WHO I and WHO II meningiomas.

Humans↗
PubMed2001

Which target for DBS in Parkinson's disease? Subthalamic nucleus versus globus pallidus internus.

We selected 14 patients with advanced idiopathic Parkinson's disease (PD) and examined the clinical effects of STN DBS versus GPi DBS. Nine patients underwent bilateral STN DBS and five underwent bilateral GPi patients. All patients were followed for at least 12 months. The evaluation was performed on and off drug before surgery; on-drug/on-DBS and off-drug/on-DBS at 1, 3, 6 and 12 months after stereotactic surgery. At 1 and 3 months after surgery in off-drug/on-DBS condition, both groups showed an improvement in motor score (UPDRS III). Nevertheless, the results changed after long-term stimulation in the two groups. Chronic STN DBS is superior to GPi DBS in the amelioration of the clinical features and in the decrease of time spent in the off state. The efficacy in reduction of LID was comparable at 1 and 3 months after surgery, but the results were better in STN DBS after chronic stimulation. The L-dopa dose was reduced only in the STN group.

Electric Stimulation Therapy↗
PubMed2001

Oligodendroglioma: HMB-45 positivity using catalyzed signal amplification method: an immunohistochemical (HMB-45, CD31, p53, Mib-1) and ultrastructural study.

Although melanin synthesis and the presence of melanosomes are exceptionally reported in nervous system tumors, there is no record of melanotic oligodendrogliomas in the literature. The purpose of the current study was to evaluate whether melanosomes are immunohistochemically and ultrastructurally detectable in nonmelanotic oligodendrogliomas and to verify whether these data are related to prognosis. Thirty surgical specimens (19 primary lesions and 11 recurrences) from 19 patients were examined. Median survival was 80 months. Immunohistochemical studies were performed using the monoclonal antibodies HMB-45, CD31. Mib-1, and p53. Using catalyzed signal amplification (CSA), HMB-45 positivity was noticed in 3 (10%) of the oligodendrogliomas being studied. No correlation with survival was found. Ultrastructural examination displayed the presence of melanosomelike structures. Tumor vascularization, estimated by means of CD31 antibody, was increased in 6 of 19 primary lesions but there was no significant correlation with survival. Nine of the19 primary lesions were p53 negative. In these cases, survival was longer than in p53-positive tumors (P = 0.0213). Proliferation rate, evaluated with Mib-1, was unrelated to survival, but proved greater in recurrences (10 of 11 cases) than in primary tumors (7 of 19 lesions; P = 0.007).

Adult↗
PubMed1999

[Metastatic brain tumors].

211 patients operated on for brain metastases have been selected through a review of specimens from the Department of Pathology of the University of Florence covering the period between 1980 to 1995. 140 patients (66%) are males and 71 (34%) are females. Average age is 59 years ranging from 33 to 79 years of age. Lung tumours (47%) and breast cancer (9%) are most frequently responsible for brain metastases. In 17% of the patients, the primary lesion was unknown. The average survival was 14 months and in 8 patients (4%) it was more 5 years. In 36 cases (17%) recurrence appeared 8 months after the first operation. Survival in these patients averaged 20 months from the diagnosis of brain metastases and 11 months after the discovery of the relapses. It is not significantly different from that of patients without evidence of relapsed metastases in the brain (13 months). Prognostically renal carcinoma behaves more favourably, average survival (27 months); on the contrary prognosis of metastatic melanoma is ominous (7 months). Metastases from unknown primaries do not have a significant different prognosis from all the other lesions.

Adult↗
PubMed1998

Surgical treatment of intracranial aneurysms in patients aged over 70: 25 years of experience.

Many references and communications regarding neurosurgical topics in elderly patients underline the interest of our Unit for this subject. We already presented in 1978 a series of 75 patients over 60 years of age operated on for intracranial aneurysms; we reported a 90% of success in all the cases operated with clinical grade 1 or 2 according to Botterel grading system on admission. In 1986, during the XXXV Congress of the Italian Neurosurgical Society, we presented other 15 cases operated for intracranial aneurysm over 70 years of age. We present an upgrading of our casistic.

Aged↗
PubMed1997

Two-step development of a pituitary adenoma: from hyperprolactinemic syndrome to Cushing's disease.

In this report we describe the case of a young female patient with amenorrhea-galactorrhea syndrome apparently due to pituitary PRL-secreting adenoma who, after three years of dopaminergic therapy without any shrinkage of the tumor, developed true Cushing's disease. Progression from hyperprolactinemia to hypersecretion of ACTH has been rarely described and it may be due to different possibilities. However, histopathological and immunohistochemical studies of the adenoma showed a pattern of PRL negative and ACTH positive cells, excluding mixed pituitary tumor. In order to explain the progression from hyperprolactinemia with amenorrhea-galactorrhea to an ACTH hypersecretion syndrome, it must be hypothesized either pituitary stalk compression or the influence of paracrine regulation factor(s) (such as Galanine) due to an "initially silent" corticotropinoma. This case confirms that the presence of hyperprolactinemia in a patient with pituitary tumor and amenorrhea-galactorrhea syndrome is insufficient to confidently conclude for prolactinoma. Furthermore, it underlines the importance both of clinically monitoring the patient with prolactin pituitary adenoma if dopaminergic therapy does not reduce tumor volume, and of accurately and repeatedly measuring the other pituitary hormonal secretions.

Adult↗
PubMed1996

Screening for mutations in the neurofibromatosis type 2 (NF2) gene in sporadic meningiomas.

Meningiomas are benign tumors of the central nervous system. They are usually sporadic but can also occur associated with the neurofibromatosis type 2 (NF2) syndrome. The gene responsible for NF2, recently isolated from chromosome 22, encodes a membrane-organizing protein that shows high sequence homology to a protein family thought to link the cytoskeleton with membrane proteins. Mutations of the NF2gene have been described in sporadic meningiomas, exclusively in tumors that show loss of heterozygosity (LOH) of 22q. These preliminary results indicate that the NF2 gene is involved in the pathogenesis of at least a subset of meningiomas, where it does indeed behave as a tumor suppressor gene. In order to characterize better the role of the NF2 gene in the genesis of meningiomas we have examined the entire coding sequence of the gene in 125 meningiomas by single-strand conformational polymorphism analysis; furthermore, LOH analysis for markers of 22q has been carried out. Inactivating mutations were identified in 30% of our samples, all of which also showed LOH of 22q. The majority of mutations identified were frameshifts and nonsense mutations, which are predicted to produce a truncated or nonfunctional protein. We also found two missense and three in-frame deletions that may pinpoint specific regions of the protein critical to its function. Furthermore, the distribution of mutations throughout the gene, suggested that exons 2, 3, 5, 11 and 13 are more frequently involved. Our results reconfirm the importance of the NF2 gene in the pathogenesis of meningiomas and also suggest that there may be a nonrandom clustering of mutations throughout the gene.

Base Sequence↗
PubMed1996

Analysis of the neurofibromatosis type 2 gene in different human tumors of neuroectodermal origin.

The autosomal dominant syndrome neurofibromatosis type 2 (NF2) is characterized by the development of bilateral vestibular schwannomas, meningiomas, ependymomas and gliomas. The NF2 gene, recently isolated from chromosome 22, is mutated in both sporadic and NF2 tumors such as schwannomas, meningiomas and ependymomas. Mutations of the gene have been described not only in the neoplasms usually associated with NF2, but also in 30% of the melanomas and 41 % of the mesotheliomas analyzed. In particular, the finding of mutations in melanomas supports the hypothesis that the NF2 gene is involved in the genesis of several tumor types that arise from the embryonic neural crest. In this study we examined, by single-strand conformational polymorphism (SSCP) analysis, 41 tumors of the central nervous system (11 schwannomas and 30 gliomas), 19 melanomas and 15 Merkel cell carcinoma specimens for mutations in the coding sequence of the NF2 gene. We found three inactivating mutations of the NF2 gene in schwannomas. No alterations of the gene were detected by SSCP analysis of the other tumors. These results confirm the role of NF2 in pathogenesis of schwannomas, but do not define its significance in the genesis of the other neuroectodermal tumors studied.

Central Nervous System Neoplasms↗
PubMed1995

Somatic mutations in the neurofibromatosis type 2 gene in sporadic meningiomas.

Meningiomas are benign tumors of the central nervous system. Although usually sporadic, they can occur in patients affected by the autosomal dominant syndrome, neurofibromatosis type 2 (NF2). The NF2 gene has recently been isolated from chromosome 22. The presence of germline mutations in NF2 patients and the loss of heterozygosity (LOH) on 22q in NF2 tumors support the hypothesis that the NF2 gene acts as a tumor suppressor. Cytogenetic and LOH studies have suggested that the gene responsible for the development of meningiomas is located in the region of 22q in which the NF2 gene maps. The meningiomas gene could therefore be the NF2 gene itself. Recently, somatic mutations of the NF2 gene have been identified in sporadic meningiomas, thus supporting the hypothesis that the NF2 gene is also important in meningioma pathogenesis. In this study, we analyzed sixty-one sporadic meningiomas for LOH of 22q and for mutations in the NF2 gene. LOH was detected in 36 of the 60 informative tumors. Single-strand conformational polymorphism analysis was used to identify nine mutations in five of the eight exons of the NF2 gene studied. The nine tumors with an altered NF2 gene also showed LOH for 22q markers. These results further support the hypothesis that mutations in the NF2 gene are a critical pathogenetic event in at least some meningiomas.

Aged↗
PubMed1994

A further case of giant intrasellar carotid aneurysm mimicking a pituitary adenoma: the relevance of a multivariate approach in differential diagnosis.

We describe a 53 year old woman who progressively showed a left extrinsic oculomotor paresis, at first suggesting ocular myasthenia, which was ruled out by a negative Tensilon test. A CT scan of the brain revealed a pituitary mass consistent with an adenoma which was confirmed by endocrinological investigation and standard MRI. Carotid angiography, performed the day before the scheduled trans-sphenoidal surgery, clearly showed a giant intrasellar aneurysm of the left carotid syphon. An extra-intracranial by-pass with occlusion of the internal carotid artery was successfully executed.

Adenoma↗
PubMed1991

Correlation between cytogenetic data and ganglioside pattern in human meningiomas.

Partial or total loss of chromosome 22 is often associated with tumors of the central nervous system and in particular with meningiomas. As in the case of other tumors, the ganglioside pattern is modified in transformed tissues. Cytogenetic analysis of 30 human meningiomas has been performed and the results compared to biochemical analysis of ganglioside distribution on the membrane surface. The meningiomas were divided into 2 groups on the basis of the presence or absence of chromosome 22. Thirteen tumors exhibited partial or total monosomy of the chromosome, whereas 17 were normal or showed other chromosomal anomalies. The GM3 and GD3 content of the meningiomas belonging to the 2 groups revealed a significant correlation between amount and reciprocal ratio of these 2 gangliosides and cytogenetic data. Tumors with monosomy 22 had a higher content of ganglioside GD3 than samples without monosomy 22, where the main ganglioside was GM3. Other gangliosides such as GM1, GD1a, GD1b and GT were present in various amounts in the 2 groups. Considering the biosynthetic pathway of gangliosides, we hypothesize the involvement of a gene located on chromosome 22 in the regulation of the enzymes which catalyze either GD3 synthesis (sialyltransferase 2, SAT-2) or its degradation to GM3 (neuraminidase).

Adult↗
PubMed1984

Visual suppression test and ocular dysmetria: some electronystagmographic findings relevant to the assessment of size of cerebellopontine angle tumors.

Patients with cerebellopontine angle tumors underwent vestibular examination, testing of voluntary fast and slow conjugate eye movements and of visual-vestibular interaction (visual suppression test--VST) by electronystagmography (ENG). Both spontaneous and evoked nystagmus (Ny) and dysmetric alterations of the voluntary conjugate eye movements are relevant to cerebellopontine pathology. This study shows that ENG may reveal damage to the vestibular brain-stem and archicerebellar structures, the ENG signs of which very often precede the clinical signs of compression. In cranial nerve VIII neuromas vestibular and oculomotor instrumental investigations yield valuable clues for early diagnosis of tumor transition from the otological to the neurosurgical stage.

Arachnoid↗