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N Kopp

Publications and source records attributed to N Kopp.

At least 19 recordsLinked to original sources
PubMed2002

[Hashimoto's encephalopathy: an anatomicoclinical observation].

Hashimoto's encephalopathy (HE) is a rare neurological complication of chronic lymphocytic thyroiditis. As its clinical presentation is aspecific, other etiologies of acute encephalopathy have to be ruled out. We report the case of a 29-year old woman with neuropsychiatric signs preceding coma, myoclonus and epileptic seizures. Clinical and electroencephalographic features were consistent with the diagnosis of new variant of Creutzfeldt-Jakob disease. However, high titres of antithyroid antibodies in serum directed towards the diagnosis of HE. Despite oral steroids, the patient died five months later. Neuropathological findings ruled out spongiform encephalopathy and disclosed aspecific activated microglia. Our observation suggests that this process could be involved in the pathogenesis of HE. Even in the absence of clinical dysthyroidism, HE diagnosis has to be suspected in the settings of acute encephalopathy associated with seric antithyroid antibodies.

Acute Disease↗
PubMed2001

Regional distribution of benzodiazepine binding sites in the human newborn and infant hypothalamus. A quantitative autoradiographic study.

Using in vitro quantitative autoradiography and [3H]flunitrazepam we examined the rostrocaudal distribution of benzodiazepine binding sites in the human neonate/infant hypothalamus. The autoradiographic analysis shows the presence of a heterogeneous distribution throughout the rostrocaudal extent of this brain structure. High [3H]flunitrazepam binding corresponds primarily to the diagonal band of Broca and the preoptic region. The labelling in the preoptic region showed a rostrocaudal increase, contrasting in that with the other hypothalamic structures. Intermediate densities were present in the septohypothalamic, suprachiasmatic, periventricular and paraventricular nuclei as well as in the mammillary complex. Low binding was observed in the other hypothalamic structures. The benzodiazepine binding sites analyzed belong mostly to type II receptors. In an attempt to unravel possible differences related to age, we compared the autoradiographic distribution in three postnatal age ranges. The topographical distribution of these binding sites was almost identical in each period analyzed. We found, however, that benzodiazepine binding is generally low in the neonatal period and a tendency in increasing densities is observed during development. Taken together, these results provide evidence for a large distribution of benzodiazepine binding sites in neonate/infant hypothalamus, suggesting their implication in the development of this brain structure and the maintenance of its various functions.

Age Factors↗
PubMed2001

Adaptation of the bovine spongiform encephalopathy agent to primates and comparison with Creutzfeldt-- Jakob disease: implications for human health.

There is substantial scientific evidence to support the notion that bovine spongiform encephalopathy (BSE) has contaminated human beings, causing variant Creutzfeldt-Jakob disease (vCJD). This disease has raised concerns about the possibility of an iatrogenic secondary transmission to humans, because the biological properties of the primate-adapted BSE agent are unknown. We show that (i) BSE can be transmitted from primate to primate by intravenous route in 25 months, and (ii) an iatrogenic transmission of vCJD to humans could be readily recognized pathologically, whether it occurs by the central or peripheral route. Strain typing in mice demonstrates that the BSE agent adapts to macaques in the same way as it does to humans and confirms that the BSE agent is responsible for vCJD not only in the United Kingdom but also in France. The agent responsible for French iatrogenic growth hormone-linked CJD taken as a control is very different from vCJD but is similar to that found in one case of sporadic CJD and one sheep scrapie isolate. These data will be key in identifying the origin of human cases of prion disease, including accidental vCJD transmission, and could provide bases for vCJD risk assessment.

Adaptation, Biological↗
PubMed2001

Paraneoplastic anti-CV2 antibodies react with peripheral nerve and are associated with a mixed axonal and demyelinating peripheral neuropathy.

Subacute sensory neuronopathy with anti-Hu antibodies is the best-characterized paraneoplastic peripheral neuropathy associated with carcinoma. Anti-CV2 antibodies, another group of paraneoplastic antibodies, react with a 66-kd brain protein belonging to the family of Ulip/CRMP proteins. The manifestations associated with anti-CV2 antibodies include cerebellar degeneration, uveitis, and peripheral neuropathy. Some of these patients also have anti-Hu antibodies. We have compared the clinical, electrophysiological, and pathological characteristics of the peripheral neuropathy in 9 patients with anti-CV2 antibodies (3 of whom also had anti-Hu antibodies) and 12 patients with only anti-Hu antibodies. Data for patients with anti-Hu antibodies alone indicated subacute sensory neuronopathy. Patients with anti-CV2 antibodies had a mixed axonal and demyelinating sensory motor neuropathy that was sometimes superimposed on subacute sensory neuronopathy when both anti-CV2 and anti-Hu antibodies were present. Unlike anti-Hu antibodies, anti-CV2 antibodies reacted with peripheral nerve antigens, as shown by their ability to bind to a 66-kd protein in human and rat nerve on Western blot analysis and to immunolabel peripheral nerve axons and sensory neurons on immunohistochemical study.

Aged↗
PubMed2001

Immunohistochemical distribution of DSIP immunoreactivity in the human hypothalamus during the first postnatal year. A preliminary report.

The distribution of DSIP-IR cell bodies and fibers was investigated in the normal human hypothalamus during the first postnatal year using the indirect immunofluorescence technique. The analysis of the immunohistochemical patterns obtained in the seven cases analyzed showed regional differences in the localization of cell bodies and fibers. Immunoreactive perikarya were relatively few, and were mostly scattered throughout the anterior and the mediobasal hypothalamus. DSIP-IR fibers and terminal-like structures were observed throughout the rostro-caudal extent of the hypothalamic region. In the present study, we noticed qualitative changes in the density of DSIP immunoreactivity in several hypothalamic structures such as the preoptic area and the median eminence with respect to age. These postnatal differences observed for DSIP could be related to neuronal maturation processes occurring at this period in the central nervous system as well as other physiological processes controlling the evolution of DSIP concentrations. These data are compatible with the proposed role of the neuropeptide in the regulation of many postnatal physiological functions.

Aging↗
PubMed2000

Dementia with Lewy bodies in a neuropathologic series of suspected Creutzfeldt-Jakob disease.

Discriminating Creutzfeldt-Jakob disease (CJD) from dementia with Lewy bodies (DLB) may be clinically difficult to achieve. The authors describe 10 patients with DLB initially referred to the French Network of Human Spongiform Encephalopathies as having suspected CJD. In a series of 465 autopsied cases, DLB ranked second among degenerative alternative diagnoses to CJD. The authors analyzed the factors that contributed to misleading the diagnosis, and suggest that the detection of 14-3-3 protein in CSF may be useful to distinguish CJD from DLB.

Aged↗
PubMed2000

Genetic influence on the structural variations of the abnormal prion protein.

Prion diseases are characterized by the presence of the abnormal prion protein PrP(Sc), which is believed to be generated by the conversion of the alpha-helical structure that predominates in the normal PrP isoform into a beta-sheet structure resistant to proteinase K (PK). In human prion diseases, two major types of PrP(Sc), type 1 and 2, can be distinguished based on the difference in electrophoretic migration of the PK-resistant core fragment. In this study, protein sequencing was used to identify the PK cleavage sites of PrP(Sc) in 36 cases of prion diseases. We demonstrated two primary cleavage sites at residue 82 and residue 97 for type 1 and type 2 PrP(Sc), respectively, and numerous secondary cleavages distributed along the region spanning residues 74-102. Accordingly, we identify three regions in PrP(Sc): one N-terminal (residues 23-73) that is invariably PK-sensitive, one C-terminal (residues 103-231) that is invariably PK-resistant, and a third variable region (residues 74-102) where the site of the PK cleavage, likely reflecting the extent of the beta-sheet structure, varies mostly as a function of the PrP genotype at codon 129.

Brain Chemistry↗
PubMed2000

Neuropathologic variants of sporadic Creutzfeldt-Jakob disease and codon 129 of PrP gene.

OBJECTIVES: To determine the contribution of methionine/valine (Met/Val) polymorphism at codon 129 of the prion protein (PrP) gene in the neuropathologic pattern and mechanisms of lesion development in sporadic Creutzfeldt-Jakob disease. BACKGROUND: Creutzfeldt-Jakob disease is a transmissible spongiform encephalopathy characterized by a conformational change of PrP and a variety of PrP deposits in the brain, some of which aggregate into amyloid plaques. METHODS: The authors semiquantitatively assessed neuropathologic lesions and performed PrP immunolabeling in 70 patients (39 Met/Met, 11 Met/Val, 20 Val/Val) who had died in France between 1994 and 1998. RESULTS: Met/Met cases (mild lesions mostly involving the occipital areas, low PrP load, few focal PrP nonamyloid deposits, no amyloid plaques) contrasted with Met/Val cases (marked lesions especially in the parahippocampal gyrus, high PrP load, numerous amyloid plaques) and with Val/Val cases (younger patients, longer course of disease: 11.5 +/- 3 months, and distinct neuropathology: severe lesions heavily involving the hippocampal formation and basal ganglia, high PrP load, numerous focal nonamyloid deposits, rare amyloid plaques). The course of Val/Val patients younger than age 55 was particularly long (19.9 +/- 7 months), and the isocortex bore the brunt of the pathology, suggesting a distinct variety. CONCLUSIONS: Polymorphism at codon 129 modulates the phenotype of sporadic Creutzfeldt-Jakob disease. The Val genotype enhances the production of proteinase-resistant PrP, and the Met/Val genotype facilitates its aggregation into amyloid plaques.

Age Distribution↗
PubMed2000

Detection and cellular localization of enterovirus RNA sequences in spinal cord of patients with ALS.

OBJECTIVE: To investigate the possible association of persistent enterovirus (EV) infection with the development of ALS. BACKGROUND: Although ALS is a clinically well-defined motor neuron disease, little is known about the etiology and pathogenesis of the sporadic cases. Among the different causes that have been hypothesized, conflicting results have been reported about the possible role of persistent enteroviral infection. METHODS: Reverse transcriptase-PCR (RT-PCR) and direct RT in situ PCR (RT-IS-PCR) were performed in formaldehyde-fixed spinal cord samples of 17 patients with confirmed ALS and 29 control subjects with no history of motor neuron disease. When obtained, PCR products were sequenced subsequently. RESULTS: Using direct RT-IS-PCR, EV nucleic acid sequences were detected in 15 (88.3%) of 17 patients with ALS compared to 1 (3.4%) of 29 control subjects. PCR products were located in neuronal cell bodies of the anterior horns of the spinal cord. The RT-PCR products obtained in 13 of the 17 patients with ALS showed between 94% and 86% homology with echovirus 7 sequences. CONCLUSION: The 88.3% rate of detection of enterovirus (EV) nucleic acids in the neuronal cell bodies within the gray matter of the spinal cord of patients with ALS strongly suggests association between persistent EV RNA and ALS. Further work is required to confirm that the persisting EV sequences we detected are somehow involved in the development of ALS.

Amyotrophic Lateral Sclerosis↗
PubMed2000

Electron microsocopy of brain amyloid plaques from a patient with new variant Creutzfeldt-Jakob disease.

Cerebral cortex biopsy from a patient with new variant Creutzfeldt-Jakob disease (nvCJD) has been examined at the electron microscope level. Spongiform changes corresponded mostly to distended neurites scattered in the neuropil or surrounding amyloid plaques. These latter exhibited heterogeneous submicroscopic morphology including variable amount of loosely interwoven amyloid fibrils admixed in a cellular-rich environment constituted essentially by abnormal neuronal processes. By immunoelectron microscopy, fibrils and some membrane structures reacted with anti-prion protein (PrP) antibodies. One striking aspect was the presence of many small dystrophic neurites without paired helical filaments. Moreover, amyloid fibrils showed unexpected intimate association with abnormal membranes, suggesting a relationship between PrP fibrillogenesis and membrane alteration. These ultrastructural findings provide an additional criterion to distinguish nvCJD-from sporadic CJD-type plaques and reinforce the hypothesis that nvCJD brain is infected by a distinctive strain of the transmissible agent encephalopathy.

Adult↗
PubMed2000

The first case of new variant Creutzfeldt-Jakob disease in France: clinical data and neuropathological findings.

Clinical data and autopsy findings in a case of new variant Creutzfeldt-Jakob disease (vCJD) are reported. This case, the first histologically confirmed case described outside the United Kingdom, very much resembles the cases described by Will et al. [(1996) Lancet 347:921-925] and Zeidler et al. [(1997) Lancet 350:903-908, 908-910]. Neuropathological studies failed to reveal any conspicuous clues that could be relevant for understanding the pathophysiology of the disease. For epidemiological surveillance, neuropathologists should scrutinize suspected cases keeping in mind the possibility of vCJD.

Adult↗
PubMed2000

[Amyotrophic lateral sclerosis: a role for enteroviruses?].

Amyotrophic lateral sclerosis (ALS) is the most frequent motor neuron disease. Although it is a clinically well defined disease, its etiology remains unknown. Among, various hypotheses, the putative role of enteroviruses has been recently suggested by the detection of enteroviral sequences in neurons of spinal cord samples from ALS patients. However, there is a lack of consensus on the role of EV in ALS. In the present paper, we summerized the pathogenic role of these viruses, analyzed the discrepancy between different studies and speculated on the possible role of enteroviruses in ALS.

Amyotrophic Lateral Sclerosis↗
PubMed2000

Ultrastructural pathology of Creutzfeldt-Jakob disease and fatal familial insomnia.

In this study we examined well fixed brain biopsies of 9 sporadic CJD, 9 iatrogenic CJD cases, 2 hereditary CJD (Gly200Lys and Val203Iso), a case of vCJD and a case of fatal familial insomnia (FFI) from a new French family collected over the years at the Service de Neuropathologie, Hopital Neurologique, Lyon, France. Tubulovesicular structures (TVS) were found in every case including FFI and nvCJD. Thus, TVS, as we suggested previously are important pathologic structure which significance should be more extensively studied.

Amino Acid Substitution↗
PubMed1999

[Cerebral intravascular lymphoma during T CD4+ idiopathic lymphopenia syndrome].

BACKGROUND: Intravascular lymphoma is a proliferation of lymphoid cells, usually B cells, in small vessels, predominantly in the nervous system and skin. CASE REPORT: We report a case of a man with a 3-year history of lymphopenia with no detectable etiology (all viral causes were ruled out) who developed intravascular lymphoma in the cerebral vessels. DISCUSSION: This case was particular as the patient had idiopathic CD4+ lymphopenia. It points out the probable role of immunodepression in the development of lymphomas, particularly in endovascular localizations.

Aged↗
PubMed1999

Alternative exon 3 splicing of the human major protein zero gene in white blood cells and peripheral nerve tissue.

The major protein zero (MPZ) is involved in peripheral myelin folding. Using nested reverse transcription-PCR, we amplified several fragments of MPZ mRNAs in white blood cells and in peripheral nerve tissue. Cloning of PCR products revealed the existence of three alternative splicing patterns: one resulted in the complete loss of exon 3 and two others induced partial skipping of the exon 3 sequence. All three alternative splicing mechanisms produced a frame-shift and created an identical premature stop codon in exon 4. We conclude that the existence of these MPZ RNA transcript variants may be the result of deliberate splicing decisions and may have functional implications in the cell.

Actins↗
PubMed1999

Submicroscopic immunodetection of PrP in the brain of a patient with a new-variant of Creutzfeldt-Jakob disease.

We analyzed the distribution and organization of the pathological prion protein isoform (PrPsc) in the brain of new variant Creutzfeldt-Jakob disease using a sensitive post-embedding immunogold electron microscopy method. On methacrylate semithin sections, silver-PrP staining showed florid plaques, containing microvacuoles. It also revealed scattered granular and perivacuolar deposits. At the electron microscope level, plaque PrP-gold labeling was associated with filaments and flocculent amorphous material sometimes observed inside microvacuoles, considered as degenerative neurites. Outside the plaques, PrP-gold labeling was predominantly found over flocculent amorphous material and the presynaptic domain of synapses. Some lysosome-like organelles seen in the neuron perikaryon, were also found to be PrP-immunoreactive. These results are consistent with the hypothesis that the synapse is a privileged target in prion disease.

Adult↗