Biomedical subjects

Anne Vital

Publications and source records attributed to Anne Vital.

28 records · Page 2Linked to original sources

PubMed2003

Ultrastructural identification of peripheral myelin proteins by a pre-embedding immunogold labeling method.

Ultrastructural immunolabeling of peripheral nervous system components is an important tool to study the relation between structure and function. Owing to the scarcity of certain antigens and the dense structure of the peripheral nerve, a pre-embedding technique is likely appropriate. After several investigations on procedures for pre-embedding immunolabeling, we propose a method that offers a good compromise between detection of antigenic sites and preservation of morphology at the ultrastructural level, and that is easy to use and suitable for investigations on peripheral nerve biopsies from humans. Pre-fixation by immersion in paraformaldehyde/glutaraldehyde is necessary to stabilize the ultrastructure. Then, ultrasmall gold particles with silver enhancement are advised. Antibodies against myelin protein zero and myelin basic protein were chosen for demonstration. The same technique was applied to localize a 35 kDa myelin protein.

Animals↗

PubMed2003

Crow-Fukase (POEMS) syndrome: a study of peripheral nerve biopsy in five new cases.

The pathogenesis of Crow-Fukase (POEMS) syndrome is not well known, and in some cases, a definite diagnosis is difficult to establish. Nerve fibers have been studied in about 120 peripheral nerve biopsies (PNBs), and a mixture of axonal and demyelinating lesions were found in most of them. We report five new cases of Crow-Fukase (POEMS) syndrome with ultrastructural examination of their PNBs. In every case, there were features of axonal degeneration and primary demyelination. Interestingly, uncompacted myelin lamellae (UMLs) were present in every case at a percentage of 1-7. The association of UML and Crow-Fukase (POEMS) syndrome was described 20 years ago but was only reported in a few studies and found in 31 of 41 cases. In fact, this association is very significant because apart from Crow-Fukase (POEMS) syndrome, UMLs can only be found with such a frequency in rare cases of Charcot-Marie-Tooth disease type 1B. UML was also reported in acute and chronic inflammatory demyelinating polyneuropathies but at a much lower percentage. Moreover, in our five cases, UML was frequently associated with a decrease in the number of intra-axonal filaments, and this finding raises the problem of relationships between myelin formation and neurofilaments. So far, glomeruloid hemangiomas present in the dermis of some patients are considered as the only specific criteria of Crow-Fukase (POEMS) syndrome, but we think UML can also be regarded as highly suggestive of this entity on condition that a thorough ultrastructural examination of a PNB is performed.

Aged↗

PubMed2003

[Amyloid neuropathies. Histopathological study of peripheral nerve biopsy in 18 cases].

OBJECTIVES: A retrospective study of nerve and muscle biopsies since 1983, with probable amyloidosis, has been performed. MATERIALS AND METHODS: Eighteen nerve and muscle biopsies, out of 29, were selected. RESULTS: Endoneurial amyloid deposits were visible on routine sections in 11 cases, revealed by ultrastructural study in 4 cases and by Congo red and/or thioflavine stains in 3 others. Amyloid deposits were marked by anti-transthyretin (TTR) serum in 13 patients, within endoneurium in 11 cases, and only around muscle fibers in 2 others. A mutation in the TTR gene, usually Val30Met, was evidenced in 8 cases and could not be assayed in the 5 others. An immunoglobulin light chain was revealed in amyloid deposits by direct immunofluorescence in the 5 other patients, of whom 4 had multiple myeloma and the fifth a lambda light chain Bence-Jones proteinuria. CONCLUSION: Nerve biopsy revealed amyloidosis in 10 patients: 5 of them had a mutation in TTR gene, without any family history.

Adult↗

PubMed2003

[Two cases of neurocysticercosis mimicking brain tumor].

Neurocysticercosis is an infectious disorder of the central nervous system caused by Taenia solium larvae. We report two misleading cases, mimicking high grade glioma on radiology. Two patients, aged 14 and 29 respectively, developed seizure, associated with left facial paralysis in the second. For each case, radiological data revealed a solitary lesion highly suggestive of high grade glioma. Microscopically, within an important inflammatory process, a characteristic cystic formation allowed a definite diagnosis of cysticercosis. Then, for both patients, a history of migration from endemic area was demonstrated later. These cases highlight the necessary pathological examination when neurocysticercosis mimics a brain tumor.

Adolescent↗

PubMed2002

Postvaccinal inflammatory neuropathy: peripheral nerve biopsy in 3 cases.

Autoimmune inflammatory polyneuropathy (PN) can be triggered by vaccination. We report 3 such cases. A 36-year-old female nurse presented 15 days after a hepatitis B vaccination (HBV) with acute sensory disturbances in the lower limbs. She had severe ataxia but no weakness. Cerebrospinal fluid (CSF) protein level was 84 mg/100 mL, with 3 lymphocytes. A 66-year-old man presented 21 days after HBV with severe motor and sensory PN involving all 4 limbs. A 66-year-old man presented 15 days after a yellow fever vaccination with progressive motor and sensory PN involving all 4 limbs and bilateral facial paralysis. CSF protein level was 300 mg/100 mL, with 5 lymphocytes. Six weeks later, a tracheostomy was performed. In these 3 patients, the nerve deficits lasted for months. In each case, peripheral nerve biopsy showed KP1-positive histiocytes but no T-lymphocytes in the endoneurium. On ultrastructural examination, there was axonal degeneration in the first 2 cases; in case 2, a few myelinated fibers exhibited an intra-axonal macrophage but the myelin sheath was preserved. There was only 1 example of macrophage-associated demyelination in case 2, but these were numerous in case 3. It is likely that in the first 2 cases, an autoimmune reaction against some axonal or neuronal components was triggered by HBV. It induced an acute sensory ataxic PN in case 1 and an acute motor and sensory axonal neuropathy (AMSAN) in case 2. The third patient had a chronic inflammatory demyelinating PN, likely triggered by yellow fever vaccination.

Adult↗

PubMed2002

Association of elevated glial expression of interleukin-1beta with improved survival in patients with glioblastomas multiforme.

OBJECT: The aim of this study was to investigate the association of interleukin-1beta (IL-1beta) expression with improved survival in patients with glioblastomas multiforme (GBMs). Immune and vascular host-tumor interactions play a pivotal role in the control of tumor development, and inflammatory mechanisms may participate in the host's defense against tumor cells. Expression of proinflammatory cytokines and of inducible nitric oxide synthase (iNOS) has been noted in various types of malignant tumors, raising the possibility that endogenous expression of cytokines and the resulting cytotoxic action of sustained NO production play a role in the control of tumor growth. Indeed, human GBMs express variable amounts of iNOS. METHODS: In this study, the expression of iNOS and of cytokines known to upregulate IL-1beta, tumor necrosis factor-alpha, interferon-gamma or downregulate iNOS transcription (IL-10, transforming growth factor [TGF]beta1, and TGFbeta2) were measured using reverse transcription-polymerase chain reaction with competitor DNA in 39 samples of human GBM. The iNOS level in GBM was positively correlated with IL-1beta messenger (m)RNA, but not with the other cytokines tested. Immunocytochemical double labeling revealed that both anti-iNOS immunoreactivity and anti-IL-1beta immunoreactivity colocalized with glial fibrillary acidic protein immunoreactivity in GBM. Some macrophage/microglial cells also expressed iNOS, but not IL-1beta. Comparison of biological data with clinical parameters indicated that the survival duration was enhanced when levels of IL-1beta mRNA were elevated or when levels of TGFbeta2 were low, but was independent of the level of iNOS mRNA within the tumor. CONCLUSIONS: Taken together, these data indicate that the proinflammatory cytokine IL-1beta produced within GBM by glial-derived cells has a negative impact on tumor growth through a mechanism independent of iNOS induction.

Down-Regulation↗

PubMedDate not supplied

Schwannian crystalline-like inclusions bodies (Fardeau-Engel bodies) revisited in peripheral neuropathies.

In 1969, Fardeau and Engel described polygonal organelles containing crystalline-like structures located in the Schwann cell cytoplasm of unmyelinated fibers. Such inclusions were reported in various conditions, mainly with axonal lesions. They were also reported in a few cases of peripheral neuropathy associated with primary mitochondriopathy. Although they are surrounded by a double membrane, their mitochondrial origin is not definitely proven. Their significance remains obscure but they deserve to be better known as Fardeau-Engel bodies, so as not to be mistaken with mitochondrial crystalline inclusions, which are frequently observed in patients with ragged-red fibers in muscle.

Adult↗

PubMedDate not supplied

Uncompacted myelin lamellae in peripheral nerve biopsy.

Since 1979, the authors have studied 49 peripheral nerve biopsies presenting uncompacted myelin lamellae (UML). Based on the ultrastructural pattern of UML they propose a 3-category classification. The first category includes cases displaying regular UML, which was observed in 43 cases; it was more frequent in 9 cases with polyneuropathy organomegaly endocrinopathy m-protein skin changes (POEMS) syndrome as well as in 1 case of Charcot-Marie-Tooth 1B with a novel point mutation in the P0 gene. The second category consists of cases showing irregular UML, observed in 4 cases with IgM monoclonal gammopathy and anti-myelin-associated glycoprotein (MAG) activity. This group included 1 benign case and 3 B-cell malignant lymphomas. The third category is complex UML, which was present in 2 unrelated patients with an Arg 98 His missense mutation in the P0 protein gene. Irregular and complex UML are respectively related to MAG and P0, which play a crucial role in myelin lamellae compaction and adhesion.

Arginine↗

PubMedDate not supplied

Axonal degeneration with unusual lesions of the myelin in an occupational neuropathy.

A 35-year-old man had prolonged occupational exposure to lead carboxylate, triethylbenzene, xylene, and dichloromethane, when he developed a subacute predominantly sensory neuropathy. Ultrastructural examination of a peripheral nerve biopsy showed axonal degeneration and unusual lesions of the myelin, with Schwann cell sequestration of vesicular and lamellar debris. Biochemical analysis of lead in a frozen peripheral nerve specimen revealed no significant difference between the propositus and a control. The authors were unable to find any similar peripheral nerve lesions in the literature dealing with neurotoxic chemicals. Any of the several organic solvents could have equally caused the neuropathy and may have been potentialized by the other chemicals.

Adult↗

PubMedDate not supplied

Incidence of central nervous system tumors in Gironde, France.

The incidence of CNS tumors is subject to geographical and temporal variations which are poorly understood. The incidence of these tumors was studied in Gironde, a department of southwestern France with 1,058,911 inhabitants older than 16 years. We recorded any malignant or benign central nervous system (CNS) tumor diagnosed between May 1999 and April 2001 in adults living in Gironde. Three hundred and twenty-nine CNS tumors were diagnosed during the study period. The incidence of CNS tumors in adults was therefore 15.5 per 100,000. Overall, the incidence according to sex was 14.7 for males and 16.2 per 100,000 for females. The incidence rate increased according to age up to 80 years (3.7 per 100,000 for 20-29 years of age to 33.4 per 100,000 for 70-79 years of age) and reduced thereafter for gliomas. Our estimation of the incidence of CNS tumors ranks high among the earlier reports. Further analytic studies are ongoing.

Adolescent↗