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Biomedical subjects

C Vital

Publications and source records attributed to C Vital.

At least 37 records · Page 2Linked to original sources
PubMed2000

Chronic inflammatory demyelinating polyneuropathy associated with dysglobulinemia: a peripheral nerve biopsy study in 18 cases.

The possible occurrence of chronic inflammatory demyelinating polyneuropathy (CIDP) in association with an identified dysglobulinemic status is recognized and a causal relationship between the two has been suggested. We had the opportunity to study 18 patients presenting with CIDP and dysglobulinemia. This was an IgG monoclonal gammopathy (IgG MG) in 8 cases, an IgM monoclonal gammopathy (IgM MG) in 8, an IgG-IgM biclonal gammopathy in 1 case and an IgM monoclonal cryoglobulinemia in another. A peripheral nerve biopsy specimen was available for all patients and the morphological findings in these specimens in the cases of CIDP with IgG MG or cryoglobulin did not differ from those without, whereas characteristic features were observed in the cases of CIDP with IgM MG and anti-myelin associated glycoprotein activity.

Aged↗
PubMed2000

Apolipoprotein AI and transthyretin as components of amyloid fibrils in a kindred with apoAI Leu178His amyloidosis.

We found a new C-terminal amyloidogenic variant of apolipoprotein AI (apoAI), Leu178His in a French kindred, associated with cardiac and larynx amyloidosis and skin lesions with onset during the fourth decade. This single-point mutation in exon 4 of the apoAI gene was detected by DNA sequencing of polymerase chain reaction amplified material and restriction fragment length polymorphism analysis in two siblings. Blood, larynx, and skin biopsies were available from one sibling. Anti-apoAI immunoblotting of isoelectric focusing of plasma showed a +1 alteration in the charge of the protein. Extraction of fibrils from the skin biopsy revealed both full-length and N-terminal fragments of apoAI and transthyretin (TTR). ApoAI and TTR co-localized in amyloid deposits as demonstrated by immunohistochemistry. The present report, together with the first recently described C-terminal amyloidogenic variant of apoAI, Arg173Pro, shows that amyloidogenicity of apoAI is not a feature exclusive to N-terminal variants. The most striking characteristic of amyloid fibrils in Leu178His is that wild-type TTR is co-localized with apoAI in the fibrils. We have previously determined that a fraction of plasma TTR circulates in plasma bound to high-density lipoprotein and that this interaction occurs through binding to apoAI. Therefore we hypothesize that nonmutated TTR might influence deposition of apoAI as amyloid.

Adult↗
PubMed2000

Inexcitability of nerves in a fulminant case of Guillain-Barré syndrome.

A 45-year-old woman presented with a recent sensorimotor deficiency in all 4 limbs, and the next day she was totally paralyzed. A slight motor improvement began on day 27. The cerebrospinal fluid had normal cellularity, but the protein varied from 90 mg/dL on the first day to 800 mg/dL on day 15, and then 290 mg/dL on day 33. Electrophysiologic studies performed on days 15 and 23 revealed a universal peripheral nerve inexcitability. A superficial peroneal nerve biopsy was performed on day 23. Nine fascicles were examined on semi-thin sections and myelinated fiber damage varied greatly from one fascicle to another. At ultrastructural examination, certain axons were severely damaged, but the others were quite well preserved and were naked or wrapped in a myelin sheath presenting a multivesicular degeneration. A few fibers had a better-preserved myelin sheath that was sometimes dissociated by elongated processes from an invading histiocyte. Six cases of fulminant Guillain-Barré syndrome with inexcitability of nerves and ultrastructural examination of nerve fragments have been reported. Electrophysiologic study is often ambiguous and cannot determine the precise origin of such an axonal degeneration. Therefore, ultrastructural analysis of a nerve biopsy is mandatory in this setting.

Axons↗
PubMed2000

Chronic inflammatory demyelinating polyneuropathy caused by HIV infection in a patient with asymptomatic CMT 1A.

It is well known that patients with Charcot-Marie-Tooth (CMT) disease are liable to present with episodes of cortisone-responsive demyelination, and a superimposed inflammatory component has been suggested. We report a patient who presented with a chronic inflammatory demyelinating polyneuropathy due to a recent HIV infection, which revealed a previously asymptomatic CMT 1A disease documented by identification of the characteristic duplication on the p11.2 region of chromosome 17. The inflammatory process was characterized by pathologic findings on a superficial peroneal nerve biopsy, and the patient improved significantly after corticotherapy. This report gives support to the hypothesis of a genetic susceptibility to inflammatory demyelinating processes in certain CMT kindreds.

Adult↗
PubMed2000

Guillain-Barré syndrome occurring in two women after ketoacidosic comatose state disclosing an insulin-dependent diabetes mellitus.

We report two women who presented with a Guillain-Barré syndrome just after a ketoacidosic comatose state disclosing an insulin-dependent diabetes mellitus. One had characteristic clinical signs and the other had major motor involvement. At neurophysiologic investigations, one had typical demyelinating neuropathy whereas the second had mainly axonal degeneration. At ultrastructural examination of a peripheral nerve biopsy, features of macrophage-associated demyelination were present in both nerve specimens, thus confirming the diagnosis of acute inflammatory demyelinating polyneuropathy, i.e., Guillain-Barré syndrome. Prominent axonal involvement was also present in the motor nerves of the second patient. Insulin therapy had to be permanently continued and these two cases are quite different from the transient diabetes sometimes observed in certain cases of Guillain-Barré syndrome. Both the latter and insulin-dependent diabetes mellitus probably have auto-immune mechanisms. It is likely that in our two patients both auto-immune diseases were triggered by a common event. Such cases of Guillain-Barré syndrome have to be distinguished from other acute diabetic neuropathies.

Adult↗
PubMed2000

Corneal myxoma associated with keratoconus and Down's syndrome.

PURPOSE: Primary myxoma of the cornea is extremely rare. Until now, only four primary corneal myxomas were reported in the literature, whereas secondary involvement of the cornea by conjunctival and limbal tumors is much more common. METHODS: We report an additional case in a 26-year-old woman with keratoconus and Down's syndrome. Excision of the corneal mass was performed by penetrating keratoplasty. Histochemical, immunohistochemistry, and ultrastructural studies were used to obtain a definitive diagnosis. RESULTS: The tumor exhibited the characteristic histologic features of myxoma. The tumor cells showed immunoreactivity for vimentin but not for S-100 protein, epithelial membrane antigen, CAM 5.2, HHF-35, or muscle-specific actin. Ultrastructural features were fibroblast-like or stellate cells with cytoplasm containing abundant, rough reticulum and dilated cisternae. No recurrence was observed 36 months after penetrating keratoplasty. CONCLUSION: This is only the fifth report of such an occurrence. Although the coexistence of myxoma in Down's syndrome with keratoconus is described here for the first time, the differential diagnosis of apparently evident acute hydrops on clinical inspection should not rule out the possibility of a corneal myxoma. Histologic analysis should therefore be performed.

Adult↗
PubMed2000

Squamous cell carcinoma developing in an intracranial prepontine epidermoid cyst.

Intracranial epidermoid cysts represent around 0,2 to 1 % of all intracranial tumours. Rare malignant transformation of these benign lesions may occur. A 66-year-old man presented with a state of confusion. MRI demonstrated a heterogeneous signal in front of the pons and ventricular dilatation. Cerebrospinal fluid examinations disclosed inflammatory cells. The patient died six months after his first admission to hospital. At autopsy, a firm greyish tumour (3 cm-long and 1 cm-thick) was present in front of the brain stem encasing the basilar artery. Microscopic examination revealed a well-differentiated epidermoid carcinoma arising from a cystic lesion whose wall was lined by a squamous epithelium with a benign appearance. The walls of all the ventricles were lined by carcinomatous cells. There was no leptomeningeal metastasis. Twenty three other cases of such squamous cell carcinoma have been reported and most of them had died within a few months.

Basilar Artery↗
PubMed1999

Anti-MAG IgM penetration into myelinated fibers correlates with the extent of myelin widening.

The purpose of this study was to evaluate the relationship between immunoglobulin M (IgM) antibodies penetration into myelinated peripheral nerve fibers and the widening of the peripheral myelin sheaths in anti-myelin-associated glycoprotein (anti-MAG) demyelinating IgM monoclonal polyneuropathy. Demyelinating polyneuropathy with monoclonal IgM is often associated with anti-MAG autoantibodies, which are thought to initiate the disease with IgM deposits usually present on the myelin sheaths. We analyzed nerve biopsies from 12 patients with an anti-MAG demyelinating neuropathy by confocal and electron microscopy. The total number of nerve fibers and the proportion of IgM-associated fibers were quantified after immunohistochemical staining. The affinities of IgM were examined by analyzing the binding pattern of serum IgM on normal peripheral nerve sections. Ultrastructural examinations of the biopsies showed a good correlation between in situ widened myelin sheaths and the IgM penetration level into myelinated fibers. The terminal complement complex appears not be involved in the penetration of IgM into the myelinated fibers. Our findings suggest a causative role of the IgM anti-MAG antibodies in the ultrastructural modifications of the myelin sheaths. The basement membrane and myelin components appear to be the major targets of the IgM monoclonal antibodies. However, the pathogenic mechanism whereby IgM antibodies reach their targets and induce nerve damage are still unclear.

Fluorescent Antibody Technique↗
PubMed1999

Asymmetrical polyneuropathy with a stepwise progressive course and well-demarcated areas of demyelination.

A female patient was 12 years old when she presented with hemiatrophy and muscle weakness on the right side of her body. Then a stepwise worsening occurred, and at 19 years of age sensory symptoms were also noticed, as well as a mild involvement of the left part of her body. The cerebrospinal fluid (CSF) protein level was elevated without cells. The main electrophysiological abnormality was a marked temporal dispersion of the compound muscle action potentials (CMAPs). Motor nerve conduction velocities were moderately reduced. A superficial peroneal nerve biopsy revealed well-demarcated areas of demyelination with prominent Schwann cell hyperplasia. Neither deletion nor duplication of the PMP22 gene nor mutation of the P0 or connexin 32 genes was found by molecular genetic investigations. Immunotherapy was administered, and over the next 6 years the symptomatology fluctuated. This unusual disorder seems to be a variant of chronic acquired demyelinating polyneuropathy and may be immunologically mediated.

Child↗
PubMed1999

Peripheral myelin modification in CMT1B correlates with MPZ gene mutations.

Morphological modifications were investigated in the peripheral nerve of three unrelated patients with CMT1B. In two patients, molecular genetic analysis showed an Arg98His mutation in the extracellular domain of MPZ, associated with irregularly uncompacted lamellae. This observation confirms previous studies of a well-defined correlation between mutations and morphological phenotypes. In the third patient, a de novo Asp109Asn mutation was associated with abnormally thick myelin sheaths. This adds to the known list of MPZ gene mutations associated with this morphological phenotype.

Adult↗
PubMed1999

Neuronal apoptosis in Creutzfeldt-Jakob disease.

Neuronal loss is a salient feature of prion diseases; however, its causes and mechanisms are unclear The possibility that it could occur through an apoptotic process has been postulated and is consistent with the lack of inflammation in prion disorders as supported by experimental studies. In order to test this hypothesis in humans, we examined samples of frontal and temporal cerebral cortex, striatum, thalamus, and cerebellum from 16 patients who died from Creutzfeldt-Jakob disease. They included 5 sporadic cases, 5 familial, 3 iatrogenic, and 3 cases with the new variant. These were compared with age and sex matched controls. Using in situ end labelling, we identified apoptotic neurons in all the cases of Creutzfeldt-Jakob disease. A single labelled neuron was found in the eldest control. Apoptotic neurons were mostly found in damaged regions and their presence and abundance seemed to correlate closely with neuronal loss. This supports the view that apoptosis of neurons is a feature of prion diseases and may contribute to the neuronal loss which is one of the main characteristics of these conditions. Neuronal apoptosis also correlated well with microglial activation, as demonstrated by the expression of major histocompatibility complex class II antigens, and axonal damage, as identified by beta-amyloid protein precursor immunostaining. In contrast, we found no obvious relationship between the topography and severity of neuronal apoptosis and the type, topography, and abundance of prion protein deposits as demonstrated by immunocytochemistry.

Adult↗
PubMed1999

[Neuronal apoptosis in human prion diseases].

Neuronal loss is a salient feature of prion diseases; however, its causes and mechanisms are unclear. The possibility that it could occur through an apoptotic process has been postulated and this is consistent with the lack of inflammation in prion disorders as supported by experimental studies. In order to test this hypothesis in humans, we examined samples of frontal and temporal cerebral cortex, striatum, thalamus and cerebellum from 26 patients who died from prion diseases. They included 16 cases of Creutzfeldt-Jakob disease (5 sporadic cases, 5 familial, 3 iatrogenic, and 3 cases with the new variant), and 10 cases of fatal familial insomnia including 8 homozygotes methionine/methionone at codon 129 of the prion protein gene and 2 heterozygotes. These were compared with age and sex matched controls. Using in situ end labelling, we identified apoptotic neurons in all the cases of Creutzfeldt-Jakob disease. A single labelled neuron was found in the eldest control. Apoptotic neurons were mostly found in damaged regions and their presence and abundance seemed to correlate closely with neuronal loss. This supports the view that apoptosis of neurons is a feature of prion diseases and may contribute to the neuronal loss which is one of the main characteristics of these conditions. Neuronal apoptosis also correlated well with microglial activation as demonstrated by the expression of major histocompatibility complex class II antigens and axonal damage as identified by beta-amyloid protein precursor immunostaining. In contrast, we found no obvious relationship between the topography and severity of neuronal apoptosis and the type, topography and abundance of prion protein deposits as demonstrated by immunohistochemistry.

Adult↗
PubMed1999

Brain stem infiltration by mixed Langerhans cell histiocytosis and Chester-Erdheim disease: more than just an isolated case?

Langerhans cell histiocytosis is classically considered as totally different from Chester-Erdheim's disease which consists in the infiltration of various parenchymas by macrophagic CD68-positive histiocytes. We report the case of a 46-year-old woman with a long history of diabetes insipidus who presented typical lesions of Langerhans cell histiocytosis on vulvar and skin biopsies as well as bony cellular infiltrates characteristic of Chester-Erdheim's disease. A few months later she presented cerebellar disorders and died after an 18-month course. At autopsy the pons was enlarged, due to numerous cellular infiltrates which were also scattered in the middle cerebellar pedoncles, dentate nuclei, midbrain and hypothalamus. There were S100-protein positive Langerhans cells intermingled with numerous ovoid CD68-positive histiocytes. There are a few reported cases of Chester-Erdheim's disease presenting foci of Langerhans cells histiocytosis in other parenchymas. In addition, there are 10 reported cases with diabetes insipidus and bilateral infiltration of the brain stem and cerebellum, considered as presenting either one type of histiocytosis or the other. Our case demonstrates that both histiocytoses may coexist in the brain and thus correspond in fact to the same pathology in certain particular cases.

Biopsy↗
PubMed1999

Classification of sporadic Creutzfeldt-Jakob disease based on molecular and phenotypic analysis of 300 subjects.

Phenotypic heterogeneity in sporadic Creutzfeldt-Jakob disease (sCJD) is well documented, but there is not yet a systematic classification of the disease variants. In a previous study, we showed that the polymorphic codon 129 of the prion protein gene (PRNP), and two types of protease-resistant prion protein (PrP(Sc)) with distinct physicochemical properties, are major determinants of these variants. To define the full spectrum of variants, we have examined a series of 300 sCJD patients. Clinical features, PRNP genotype, and PrP(Sc) properties were determined in all subjects. In 187, we also studied neuropathological features and immunohistochemical pattern of PrP(Sc) deposition. Seventy percent of subjects showed the classic CJD phenotype, PrP(Sc) type 1, and at least one methionine allele at codon 129; 25% of cases displayed the ataxic and kuru-plaque variants, associated to PrP(Sc) type 2, and valine homozygosity or heterozygosity at codon 129, respectively. Two additional variants, which included a thalamic form of CJD and a phenotype characterized by prominent dementia and cortical pathology, were linked to PrP(Sc) type 2 and methionine homozygosity. Finally, a rare phenotype characterized by progressive dementia was linked to PrP(Sc) type 1 and valine homozygosity. The present data demonstrate the existence of six phenotypic variants of sCJD. The physicochemical properties of PrP(Sc) in conjunction with the PRNP codon 129 genotype largely determine this phenotypic variability, and allow a molecular classification of the disease variants.

Adult↗
PubMed1999

Prion disease with octapeptide repeat insertion.

OBJECTIVE: About 8% of prion disease cases are familial and a few are due to an octapeptide repeat insertion (OPRI) in the prion protein gene. A suitable neuropathological examination has been performed in 20 cases from 9 families and in 3 isolated cases. The number of OPRI ranges from 4 to 9 multiples of 24 base-pair. METHODS: Results from routine histopathological preparations and from immunohistochemistry performed after special tissue pretreatment were compared with those of molecular genetic investigation. RESULTS: Eight cases with 4 to 7 multiples of OPRI exhibited characteristic elongated deposits in the cerebellar molecular layer, which were visible on slides prepared with antibodies against the prion protein only. Conversely, 6 cases with 8 or 9 multiples of OPRI presented typical plaques already obvious on routine preparations. CONCLUSIONS: These variable modifications in the cerebellar molecular layer deserve to be underlined, in particular the elongated deposits which are characteristic for cases presenting 4 to 7 OPRI.

Adult↗
PubMed1999

[Fatal familial insomnia].

Since its description in 1986, Fatal Familial Insomnia (FFI) became the third most common inherited prion diseases (23 described families, 3 isolated cases). It is characterized by a mutation at codon 178 of the prion protein gene cosegregating with the methionine polymorphism at codon 129 of the mutated allele. Insomnia, dysautonomia, disruption of circadian rhythms and motor dysfunctions (myoclonus, ataxia, dysarthria, spasticity) are the main clinical symptoms in the homozygote patients (met/met at codon 129). Heterozygotes have motor dysfunctions from onset and cognitive changes. Pheno-typic variability does not appear to be strictly related to codon 129 polymorphism as recently stressed in some reports. Neuropathology shows marked neuronal loss and gliosis in the thalamus, especially in the medio-dorsal and antero-ventral nuclei, without any amyloïd deposits. Some spongiosis may be seen essentially in the cerebral cortex, in patients with longer duration disease. The D178N mutation coupled with the 129 valine codon is linked to a subtype of Creutzfeldt-Jakob disease. However, in these two phenotypically different diseases, two protease resistant fragments of the pathogenic PrP (PrPres) are accumulated. They differ in molecular mass. In FFI PrPres, the unglycosylated form is underrepresented. This particularity does not result from the preferential conversion of the glycosylated forms but from an inaccessibility of non glycosylated form to conversion. PrPres has been shown to be form allelic origin. Neuronal apoptosis was found to contribute to neuronal loss in FFI. Its presence correlates with neuronal loss, being invariably noticed in the thalamus and medullary nuclei. It is not correlated with PrPres accumulation. The quantity of deposits is globally low in FFI brains and rarely immunohistochemically detected. Pathogenesis of lesions and clinical signs remain to be assessed. Protein dysfunction could be hypothesized according to some clinical and experimental data as well as to the discordance between protein accumulation and programmed cell death. Neurotoxicity is also postulated. Studies on this pathology led to consider the existence of "strains" in human prion diseases. Despite remarkable advances, many issues remain unsolved in this non spongiform prion disease.

Amino Acid Substitution↗