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N Streichenberger

Publications and source records attributed to N Streichenberger.

At least 19 recordsLinked to original sources
PubMed2006

Clinical relevance of diffusion and perfusion magnetic resonance imaging in assessing intra-axial brain tumors.

Advanced magnetic resonance (MR) imaging techniques provide physiologic information that complements the anatomic information available from conventional MR imaging. We evaluated the roles of diffusion and perfusion imaging for the assessment of grade and type of histologically proven intraaxial brain tumors. A total of 28 patients with intraaxial brain tumors underwent conventional MR imaging (T2- and T1-weighted sequences after gadobenate dimeglumine injection), diffusion imaging and T2*-weighted echo-planar perfusion imaging. Examinations were performed on 19 patients during initial diagnosis and on nine patients during follow-up therapy. Determinations of relative cerebral blood volume (rCBV) and apparent diffusion coefficient (ADC) were performed in the solid parts of each tumor, peritumoral region and contralateral white matter. For gliomas, rCBV values were greater in high-grade than in low-grade tumors (3.87+/-1.94 versus 1.30+/-0.42) at the time of initial diagnosis. rCBV values were increased in all recurrent tumors, except in one patient who presented with a combination of recurrent glioblastoma and massive radionecrosis on histology. Low-grade gliomas had low rCBV even in the presence of contrast medium enhancement. Differentiation between high- and low-grade gliomas was not possible using diffusion-weighted images and ADC values alone. In the peritumoral areas of untreated high-grade gliomas and metastases, the mean rCBV values were higher for high-grade gliomas (1.7+/-0.37) than for metastases (0.54+/-0.18) while the mean ADC values were higher for metastases. The rCBV values of four lymphomas were low and the signal intensity-time curves revealed a significant increase in signal intensity after the first pass of gadobenate dimeglumine. Diffusion and perfusion imaging, even with relatively short imaging and data processing times, provide important information for lesion characterization.

Adolescent↗
PubMed2006

[Diffusion and perfusion MR imaging in cerebral lymphomas].

Because of the increasing incidence of cerebral lymphoma, it is critical for patient management to recognize the MR features of this disease. We present the characteristic morphological and functional MRI features of this tumor. The findings on MRI studies, including morphological, diffusion and perfusion imaging, performed in 9 biopsy-proven cases of cerebral lymphoma with 13 lesions are presented and analyzed, and are discussed in comparison with published literature data. All patients underwent diffusion-weighted imaging with a single shot echo-planar pulse sequence. Dynamic susceptibility-contrast MRI was performed using a T2*-weighted gradient-echo echo-planar sequence after intravenous injection of chelates of gadolinium at the rate of 6 ml/s and a temporal resolution of 1 second. All cases of cerebral lymphoma appeared hypointense or isointense on T1-weighted images and in 75% of cases iso- or hypointense on T2-weighted images. All lesions enhanced except one in a patient receiving steroid therapy. On diffusion-weighted images, tumours were hyperintense with normal or decreased ADC values (0.717+/-0.152.10-3 mm2/sec, range: 0.550-1.014) and an ADC ratio tumour/normal white matter of 0.974+/-0.190 (range: 0.768-1.410). On perfusion, the signal intensity-time curve of each tumour showed a characteristic type of curve with a significant increase of the signal intensity above the baseline and a low maximum relative cerebral blood volume ratio (rCVBmax) of 1.43+/-0.64 (0.55-2.62). Due to their higher cellularity, the lack of neoangiogenesis, and the increased permeability of the blood-brain barrier related to the infiltration of blood vessels wall by lymphomatous cells, cerebral lymphoma presents characteristic diffusion and perfusion MRI features that should be useful for diagnosis and patient follow-up.

Adult↗
PubMed2005

[Autosomal dominant limb-girdle muscular dystrophy associated with conduction defects (LGMD1B): a description of 8 new families with the LMNA gene mutations].

INTRODUCTION: Limb girdle muscular dystrophy type 1b (LGMD1B), due to LMNA gene mutations, is a relatively rare form of LGMD characterized by proximal muscle involvement associated with heart involvement comprising atrio-ventricular conduction blocks and dilated cardiomyopathy. Its clinical and genetic diagnosis is crucial for cardiac management and genetic counselling. Seven LMNA mutations have been previously reported to be responsible for LGMD1B. PATIENTS AND METHODS: We describe the neurological and cardiologic features of 14 patients belonging to 8 families in whom we identified 6 different LMNA mutations, 4 of them having never been reported. Results. Eleven patients had an LGMD1B phenotype with scapulohumeral and pelvic-femoral involvement. Thirteen patients had cardiac disease associating conduction defects (12 patients) or arrhythmias (9 patients). Seven patients needed cardiac device (pacemaker or implantable cardiac defibrillator) and two had heart transplantation. CONCLUSION: This study allowed us to specify the clinical characteristics of this entity and to outline the first phenotype/genotype relations resulting from these observations.

Adolescent↗
PubMed2005

Ultrastructural pathology of prion diseases revisited: brain biopsy studies.

We report here a detailed ultrastructural comparison of brain biopsies from 13 cases of Creutzfeldt-Jakob disease (CJD) and from one case of fatal familial insomnia (FFI). The latter disease has not heretofore benefited from ultrastructural study. In particular, we searched for tubulovesicular structures (TVS), 35-nm particles regarded as the only disease-specific structures at the level of thin-section electron microscopy. Our material consisted of brain biopsies obtained by open surgery from one FFI case from a new French family, one case of variant CJD (vCJD), nine cases of sporadic CJD (sCJD), two cases of iatrogenic (human growth hormone) CJD and one case of hereditary CJD (Val203Iso). The ultrastructural picture of the cerebral cortex of the FFI patient was virtually indistinguishable from that of CJD. TVS were found, albeit only after prolonged search. Typical spongiform change was observed, consisting of intracellular membrane-bound vacuoles containing secondary chambers (vacuoles within vacuoles) and amorphous material. Neuronal degeneration was widespread: some processes contained degenerating mitochondria and lysosomal electron-dense bodies and these met the criteria for neuroaxonal dystrophy. Other processes contained branching cisterns; still others were filled with electron-dense masses and amorphous vesicles. The overall ultrastructural appearance of variant CJD was similar to that of FFI cerebral cortex, except for a much higher number of cellular processes containing TVS. We detected TVS in the majority of sCJD cases that, in addition to typical spongiform change and robust astrocytic reaction, showed widespread neuritic and synaptic degeneration and autophagic vacuoles. We conclude that TVS are readily found in FFI, vCJD and sCJD and that widespread neuritic degeneration is a part of ultrastructural pathology in prion diseases.

Adult↗
PubMed2005

[11C]-Methionine PET: dysembryoplastic neuroepithelial tumours compared with other epileptogenic brain neoplasms.

BACKGROUND AND OBJECTIVES: Brain tumours responsible for longstanding partial epilepsy are characterised by a high prevalence of dysembryoplastic neuroepithelial tumour (DNT), whose natural evolution is much more benign than that of gliomas. The preoperative diagnosis of DNT, which is not yet feasible on the basis of available clinical and imaging data, would help optimise the therapeutic strategy for this type of tumour. This study tested whether [(11)C]-methionine positron emission tomography (MET-PET) could help to distinguish DNTs from other epileptogenic brain tumours. METHODS: Prospective study of 27 patients with partial epilepsy of at least six months duration related to a non-rapidly progressing brain tumour on magnetic resonance imaging (MRI). A structured visual analysis, which distinguished between normal, moderately abnormal, or markedly abnormal tumour methionine uptake, as well as various regions of interest and semiquantitative measurements were conducted. RESULTS: Pathological results showed 11 DNTs (41%), 5 gangliogliomas (18%), and 11 gliomas (41%). MET-PET visual findings significantly differed between the various tumour types (p<0.0002), regardless of gadolinium enhancement on MRI, and were confirmed by semiquantitative analysis (p<0.001 for all calculated ratios). All gliomas and gangliogliomas were associated with moderately or markedly increased tumour methionine uptake, whereas 7/11 DNTs had a normal methionine uptake, including all six located in the mesiotemporal structures. No DNT presented with a marked MET-PET abnormality. CONCLUSION: Normal MET-PET findings in patient with an epileptogenic and non-rapidly progressing brain tumour are suggestive of DNT, whereas a markedly increased tumour methionine uptake makes this diagnosis unlikely.

Adolescent↗
PubMed2003

Interleukin-17 increases the effects of IL-1 beta on muscle cells: arguments for the role of T cells in the pathogenesis of myositis.

We studied the production of interleukin (IL)-6 and CCL20/macrophage inflammatory protein-3 alpha (MIP-3 alpha) by human myoblasts and muscle samples in response to IL-17 alone or in combination with IL-1 beta. Both IL-17 and IL-1 beta induced IL-6 production by normal myoblasts and muscle samples. IL-17 had no effect on CCL20 production by myoblasts. Combination of IL-17 and IL-1 beta further increased IL-6 and CCL20 production by muscle samples but not that of CK. IL-17 induced also HLA class I, C-Fos, nuclear factor kappa B (NF-kappa B) and C-Jun expression by myoblasts but not that of HLA class II, CD40, vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1). Finally, immunostaining of dermatomyositis (DM) and polymyositis (PM) muscle biopsies showed IL-17 and CCL20 expression. Our study shows that low levels of cytokines produced by T cells (IL-17) and monocytes (IL-1 beta) can act in combination on skeletal myoblasts and muscle tissue.

Adjuvants, Immunologic↗
PubMed2003

[Analysis of 12 cases of McArdle's disease diagnosed after 30 years].

PURPOSE: McArdle's disease (MAD) or glycogen storage disease type V, usually starts in childhood or adolescence. Generally diagnosis is made before the early adulthood because patients present well defined syndrome and are constrained. METHOD: We retrospectively investigated all MAD cases diagnosed in the biochemical laboratory from Debrousse Hospital in Lyon, during 40 years (1962-2002). We then selected patients whose diagnosis had been made after 30 years. RESULTS: Fifteen patients answered our criteria but only 11 files could be analysed. A twelfth patient (service of internal medicine--Royan) supplemented the series. We sought the reasons of a late diagnosis: early age of beginning but few symptoms (7 cases), age of beginning higher than 20 years (5 cases including 3 after 45 years). The principal symptoms were muscular deficit and muscular pains (8 cases) and second wind phenomenon (7 cases). Creatinine phosphokinase level was constantly high. Ischemic effort test when it was carried out was constantly abnormal. Conversely electromyogram was often normal (5 cases). Several biopsies were necessary in a third of the cases to evoke the diagnosis, particularly among the patients with late onset symptoms. CONCLUSION: Diagnosis of metabolic MAD is generally easy if the interrogation finds inaugural symptoms in childhood or adolescence even if the patient consults very late in the life. The diagnosis can become much more difficult if it begins late in life (atypical symptoms, need for several muscular biopsy).

Adult↗
PubMed2003

[Pathology of spastic muscles. Study of 26 patients].

Spastic hypertonia is observed in various central neurological diseases. Pathology of spastic muscle is not well known. Tibial selective microsurgical neurotomy is used for the spastic foot treatment. Twenty-six hemiplegic patients, spastic since more than one year, underwent selective tibial microsurgical neurotomy. Biopsies of soleus, lateral and medial gastrocnemius muscles were performed during surgical treatment, after free patient consent and ethical committee approval. The aim of this study was to describe histopathological lesions of spastic muscles, with histological and histoenzymatic techniques. Histological studies revealed myogenic atrophy, concerning both types of fibers or only type II fibers. They also showed type I (slow fibers) to type II (fast fibers) transformation, in the three studied muscles. These results are similar to those described in the literature.

Adolescent↗
PubMed2003

[Symptomatic carriers of dystrophinopathy with chromosome X inactivation bias].

Several studies have recently highlighted the fact that the clinical involvement in females carrying a mutation in the dystrophin gene could be more frequent than usually thought, suggesting the need of a careful cardiac follow-up. Except for the classical chromosomal rearrangements, it was shown that a bias in the X chromosome inactivation process could be found in some affected females. We report two families illustrating different situations. The propositus of the first family, aged 32, presented with a proximal muscular weakness, increasing for three years, as well as elevated muscular enzymes in blood. Her brother suffered from classical Duchenne muscular dystrophy. Her mother was more severely affected, whereas her sister remained asymptomatic. A duplication of exons 3 to 7 of the dystrophin gene was found in all four patients. The affected carrier from the second family was a sporadic case. She has been suffering from proximal muscular weakness for six years. Muscle biopsy showed a mosaic pattern of the immunostaining using specific antidystrophin antibodies. A stop mutation was found in exon 52. Her ten year-old daughter, carrying the mutation, was asymptomatic. In both families, the inactivation profiles were in accordance with the clinical presentation. We discuss the different mechanisms that may lead to the inactivation bias in these patients, as well as the advantage and limits of using the X chromosome inactivation test as a tool for diagnosis and prognosis purpose in symptomatic carriers for dystrophinopathies.

Adolescent↗
PubMed2002

[Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (Melas) associated with a Fahr disease and cerebellar calcifications].

INTRODUCTION: Melas syndrome is a mitochondrial disease which corresponds to the association of mitochondrial encephalopathy, lactic acidosis and stroke-like espisodes. CASE REPORT: The authors report the case of a 39 year-old woman presenting with hearing loss, seizures, visual field deficit, three stroke-like episodes and calcifications of the basal ganglia and cerebellar dentate nuclei. Melas syndrome was suspected and confirmed by muscle biopsy, showing ragged red fibers and the presence of an A3243G mutation of mitochondrial DNA. CONCLUSION: This clinical, pathological and radiological observation shows that intracerebral calcifications may involve the dentate nuclei of the cerebellum in the Melas syndrome.

Adult↗
PubMed2002

[Anterior choroidal artery infarction revealing polyarteritis nodosa].

An 81-year old man presented with a sudden right ataxic hemiparesis. Brain CT scan showed a left anterior choroidal artery territory infarction. Biological signs of inflammation were present without any evidence of infection or neoplasm. The patient's clinical status deteriorated with fever, loss of weight and confusion. Muscle biopsy showed characteristic abnormalities of polyarteritis nodosa (PAN). Oral corticosteroids plus monthly pulse intravenous cyclophosphamide were started. A rapid clinical improvement was observed as well as the resolution of inflammation within one month. Twenty months later, the patient had recovered normal cognitive function and was able to carry out all usual activities. We describe the CNS complications of PAN and the therapeutic options.

Aged↗
PubMed2002

[Solitary plasmacytoma of the sphenoid. A case report].

A rare case of sphenoidal plasmacytoma in a 79 year-old male patient is reported. The diagnosis was preoperatively considered because of associated dysproteinemia and it was histopathologically confirmed on a transphenoidal biopsy specimen. Initial evaluation disclosed no systemic dissemination of the disease and a solitary plasmacytoma was diagnosed. Radiotherapy was delivered with subsequent clinical improvement and significant tumor reduction was illustrated on follow-up imaging studies. Twenty-two months after diagnosis, the patient remains asymptomatic without evidence of transformation to multiple myeloma. Only 7 comparable cases have been reported in the literature. The diagnostic, pathological and nosographic features of sphenoid plasmacytomas are discussed.

Aged↗
PubMed2001

Constrictive bronchiolitis obliterans. Characterisation of fibrogenesis and lysyl oxidase expression patterns.

The process leading to irreversible fibrotic constriction of the bronchioles was studied in two cases of bronchiolitis obliterans (BO) after bone marrow transplantation. Because lysyl oxidase (LOX) is the main collagen cross-linking enzyme that might account for irreversible fibrosis, its expression was studied together with expression of extracellular matrix (ECM) proteins. Characteristic types of lesions could be distinguished on the basis of histological and immunohistological criteria. An inflammatory stage was characterised by infiltration restricted to the bronchioles by lymphocytes and dendritic cells. A fibro-inflammatory stage was characterised by the coexistence of a persistent immune cellular lesion pattern with further focal modelling of a sub-epithelial neo-synthesised connective matrix. LOX expression was observed at the tips of intra-luminal fibrotic protrusions, together with tenascin and cellular fibronectin. A fibrotic stage was characterised by dense ECM deposits spreading throughout the peri-bronchiolar connective tissue, resulting in bronchiole obliteration and final disappearance. In contrast to reversible cases of fibrosis, persistence of long-term LOX expression reflecting continuing fibrosing activity might account for the irreversible status of BO. Our two cases illustrated that, at inflammatory and fibro-inflammatory stages, BO may be stabilised by immunosuppressive treatment, while the persistence of LOX expression in the fibrotic stage might correspond to a disease that becomes irreversible and fatal.

Adult↗
PubMed2001

Metastasis of clear-cell renal carcinoma to cerebellar hemangioblastoma in von Hippel Lindau disease: rare or not investigated?

A new case of metastatic hypernephroma to cerebellar hemangioblastoma is described in a patient affected by von Hippel-Lindau disease. To our knowledge this is the third reported case of metastasis of renal carcinoma to intracranial hemangioblastoma associated with Von Hippel-Lindau disease. The real frequency of this pathological entity and its management are not well defined.

Adult↗
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↗
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↗