129 research outputs found
Caractérisation de phénomènes anthropiques par la mesure de paramètres magnétiques sur surface décapée : Premiers résultats sur le projet Canal Seine-Nord Europe
La démarche suivie sur le projet Canal Seine-Nord Europe se veut différente de l’utilisation standard qui peut être faite de la géophysique. La volonté est d’intégrer cet outil au plus près de l’étude archéologique comme peuvent l’être la pédologie ou la cartographie des phosphates par exemple. Grâce à une interaction forte avec les archéologues et géo-archéologues du projet, de nouvelles problématiques ont été définies et mises en oeuvre. La plus intéressante est certainement l'emploi de la géophysique pour l'étude des surfaces décapées. Par cette approche, il s’agit non pas de détecter les structures mais d’apporter à l’archéologue une information nouvelle, complémentaire des données de fouilles. Par la mesure d’un ou de plusieurs paramètres magnétiques, des phénomènes anthropiques peuvent être mis en évidence et apporter des éléments pour la compréhension du site. Les différents cas présentés illustrent la diversité des problématiques pouvant faire intervenir la géophysique. Celles-ci sont nombreuses et l'apport scientifique particulièrement important. Tout en gardant un regard critique, l’étude sur surface décapée offre un très fort potentiel qui doit encore être développé. La comparaison des résultats géophysiques avec la cartographie des phosphates constitue un des axes majeurs de cette démarche.The approach adopted on the Canal Seine-Nord Europe project is different from the standard application of geophysics. The will is to integrate this tool inside the archaeological study as it is done for pedology or phosphate analysis for example. Thanks to a great interaction with archaeologists and geo-archaeologists, new issues have been defined and employed on the field. The most interesting is certainly the use of geophysics to characterise soils and archaeological layers after clearance of topsoil. Thus, the aim is not to detect features but to bring new information completing field observations. More precisely, this characterisation is essentially based on the magnetic susceptibility measurement which is closely related to anthropogenic phenomena. Different cases presented here show several issues that can call upon geophysics. Those are numerous and the scientific contribution is particularly interesting. Comparison of geophysics results with phosphate analysis constitutes one of the most interesting axes of this approach
Annœullin – Chemin Desnoullet
Deux opérations de diagnostic ont été prescrites à d’Annœullin, chemin Desnoullet, suite au dépôt de deux projets de lotissement pour une surface de 20 047 m2 et 8 748 m2. Les emprises étant adjacentes, les interventions ont été réalisées conjointement. Les sondages se sont révélés particulièrement riches en vestiges du Haut-Empire romain avec la mise au jour de 246 faits répartis sur l’ensemble des parcelles. Trois ensembles architecturaux composés de constructions sur poteaux plantés ont ét..
direct comparison of M1-AQP4-DNA-transfected cells with leaky scanning versus M23-AQP4-DNA-transfected cells as antigenic substrate
Background Neuromyelitis optica (NMO, Devic syndrome) is associated with
antibodies to aquaporin-4 (NMO-IgG/AQP4-Ab) in the majority of cases. NMO-
IgG/AQP4-Ab seropositivity in patients with NMO and its spectrum disorders has
important differential diagnostic, prognostic and therapeutic implications.
So-called cell-based assays (CBA) are thought to provide the best AQP4-Ab
detection rates. Objective To compare directly the AQP4-IgG detection rates of
the currently most widely used commercial CBA, which employs cells transfected
with a full-length (M1)-human AQP4 DNA in a fashion that allows leaky scanning
(LS) and thus expression of M23-AQP4 in addition to M1-AQP, to that of a newly
developed CBA from the same manufacturer employing cells transfected with
human M23-AQP4-DNA. Methods Results from 368 serum samples that had been
referred for routine AQP4-IgG determination and had been tested in parallel in
the two assays were compared. Results Seventy-seven out of 368 samples (20.9%)
were positive for NMO-IgG/AQP4-Ab in at least one assay. Of these, 73 (94.8%)
were positive in both assays. A single sample (1.3%) was exclusively positive
in the novel assay; three samples (3.9%) were unequivocally positive only in
the ‘classic’ assay due to high background intensity in the novel assay. Both
median fluorescence intensity and background intensity were higher in the new
assay. Conclusions This large study did not reveal significant differences in
AQP4-IgG detection rates between the ‘classic’ CBA and a new M23-DNA-based
CBA. Importantly, our results largely re-affirm the validity of previous
studies that had used the ‘classic’ AQP4-CBA to establish NMO-IgG/AQP4-Ab
seropositivity rates in NMO and in a variety of NMO spectrum disorders
Aquaporin-4 antibody testing: direct comparison of M1-AQP4-DNA-transfected cells with leaky scanning versus M23-AQP4-DNA-transfected cells as antigenic substrate
Background: Neuromyelitis optica (NMO, Devic syndrome) is associated with antibodies to aquaporin-4 (NMO-IgG/AQP4-Ab) in the majority of cases. NMO-IgG/AQP4-Ab seropositivity in patients with NMO and its spectrum disorders has important differential diagnostic, prognostic and therapeutic implications. So-called cell-based assays (CBA) are thought to provide the best AQP4-Ab detection rates. Objective: To compare directly the AQP4-IgG detection rates of the currently most widely used commercial CBA, which employs cells transfected with a full-length (M1)-human AQP4 DNA in a fashion that allows leaky scanning (LS) and thus expression of M23-AQP4 in addition to M1-AQP, to that of a newly developed CBA from the same manufacturer employing cells transfected with human M23-AQP4-DNA. Methods: Results from 368 serum samples that had been referred for routine AQP4-IgG determination and had been tested in parallel in the two assays were compared. Results: Seventy-seven out of 368 samples (20.9%) were positive for NMO-IgG/AQP4-Ab in at least one assay. Of these, 73 (94.8%) were positive in both assays. A single sample (1.3%) was exclusively positive in the novel assay; three samples (3.9%) were unequivocally positive only in the ‘classic’ assay due to high background intensity in the novel assay. Both median fluorescence intensity and background intensity were higher in the new assay. Conclusions: This large study did not reveal significant differences in AQP4-IgG detection rates between the ‘classic’ CBA and a new M23-DNA-based CBA. Importantly, our results largely re-affirm the validity of previous studies that had used the ‘classic’ AQP4-CBA to establish NMO-IgG/AQP4-Ab seropositivity rates in NMO and in a variety of NMO spectrum disorders
À la recherche des espaces de stabulation. Étude pluridisciplinaire d’habitats du Néolithique au Moyen Âge dans le nord de la France
Les indices découverts lors de fouilles de constructions anciennes permettent d’étayer l’hypothèse de leur fonction (espace artisanal, espace domestique, maison-étable, bâtiment d’élevage,…) : il s’agit d’éléments architecturaux (murs, sablières, trous de poteaux) et de leur disposition dans l’espace (partitions internes, relations entre structures) ; de la répartition des artefacts découverts dans les structures du bâtiment ou situés dans l’environnement proche, tels que les restes céramique..
Automated Indirect Immunofluorescence Evaluation of Antinuclear Autoantibodies on HEp-2 Cells
Indirect immunofluorescence (IIF) on human epithelial (HEp-2) cells is considered as the gold standard screening method for the detection of antinuclear autoantibodies (ANA). However, in terms of automation and standardization, it has not been able to keep pace with most other analytical techniques used in diagnostic laboratories. Although there are already some automation solutions for IIF incubation in the market, the automation of result evaluation is still in its infancy. Therefore, the EUROPattern Suite has been developed as a comprehensive automated processing and interpretation system for standardized and efficient ANA detection by HEp-2 cell-based IIF. In this study, the automated pattern recognition was compared to conventional visual interpretation in a total of 351 sera. In the discrimination of positive from negative samples, concordant results between visual and automated evaluation were obtained for 349 sera (99.4%, kappa = 0.984). The system missed out none of the 272 antibody-positive samples and identified 77 out of 79 visually negative samples (analytical sensitivity/specificity: 100%/97.5%). Moreover, 94.0% of all main antibody patterns were recognized correctly by the software. Owing to its performance characteristics, EUROPattern enables fast, objective, and economic IIF ANA analysis and has the potential to reduce intra- and interlaboratory variability
Rediscovery of the Anti-Pancreatic Antibodies and Evaluation of their Prognostic Value in a Prospective Clinical Cohort of Crohn's Patients: The Importance of Specific Target Antigens [GP2 and CUZD1].
BACKGROUNDS
Glycoprotein 2[GP2] and CUB zona pellucida-like domain 1[CUZD1] belong to protein families involved in gut innate immunity processes and have recently been identified as specific targets of anti-pancreatic autoantibodies [PAbs] in Crohn's disease[CD]. We aimed to determine the prognostic potential of novel target-specific PAbs regarding long-term disease course of an adult CD patient cohort.
METHODS
Sera of 458 consecutive well-characterised IBD patients from a single referral IBD centre were tested by enzyme-linked immunosorbent assay [ELISA] with isoform 4 of recombinant GP2 [anti-MZGP2 and anti-GP2 IgA/IgG] and indirect immunofluorescence test [IIFT] system with GP2 and CUZD1 expressing transfected HEK 293 cells [anti-rPAg2 and rPAg1 IgA/IgG]. Clinical data were available on complicated disease or surgical interventions as well as disease activity and medical treatment during the prospective follow-up [median, 108 months].
RESULTS
Totals of 12.4% and 20.8% of CD patients were positive for IgA/IgG type of anti-GP2 and anti-CUZD1, respectively, with a significant difference compared with UC [p < 0.01]. Antibody status was stable over time. Agreement among three different anti-GP2 assays was good. Positivity for PAbs, mainly IgA subtypes, predicted a faster progression towards complicated disease course. In Kaplan-Meier analysis, time to surgery or development of perianal disease was associated with anti-GP2 IgA [pLogRank < 0.01] or anti-CUZD1 IgA [pLogRank < 0.001] positivity, respectively. Anti-CUZD1 IgA remained an independent predictor in the multivariate Cox-regression model (hazard ratio [HR]: 3.43, 95% confidence interval [CI]: 1.68-7.02, p < 0.001).
CONCLUSIONS
The present study has shown that specific PAbs [especially IgA subtype] predict complicated disease course including the development of perianal disease in CD
Clinical, paraclinical and serological findings in Susac syndrome: an international multicenter study
Background: Susac syndrome (SuS) is a rare disorder thought to be caused by autoimmune-mediated occlusions of microvessels in the brain, retina and inner ear leading to central nervous system (CNS) dysfunction, visual disturbances due to branch retinal artery occlusions (BRAO), and hearing deficits. Recently, a role for anti-endothelial cell antibodies (AECA) in SuS has been proposed. Objectives: To report the clinical and paraclinical findings in the largest single series of patients so far and to investigate the frequency, titers, and clinical relevance of AECA in SuS. Patients and methods: A total of 107 serum samples from 20 patients with definite SuS, 5 with abortive forms of SuS (all with BRAO), and 70 controls were tested for AECA by immunohistochemistry employing primate brain tissue sections. Results: IgG-AECA >1:100 were detected in 25% (5/20) of patients with definite SuS and in 4.3% (3/70) of the controls. Median titers were significantly higher in SuS (1:3200, range 1:100 to 1:17500) than in controls (1:100, range 1:10 to 1:320); IgG-AECA titers >1:320 were exclusively present in patients with SuS; three controls had very low titers (1:10). Follow-up samples (n = 4) from a seropositive SuS patient obtained over a period of 29 months remained positive at high titers. In all seropositive cases, AECA belonged to the complement-activating IgG1 subclass. All but one of the IgG-AECA-positive samples were positive also for IgA-AECA and 45% for IgM-AECA. SuS took a severe and relapsing course in most patients and was associated with bilateral visual and hearing impairment, a broad panel of neurological and neuropsychological symptoms, and brain atrophy in the majority of cases. Seropositive and seronegative patients did not differ with regard to any of the clinical or paraclinical parameters analyzed. Conclusions: SuS took a severe and protracted course in the present cohort, resulting in significant impairment. Our finding of high-titer IgG1 and IgM AECA in some patients suggest that humoral autoimmunity targeting the microvasculature may play a role in the pathogenesis of SuS, at least in a subset of patients. Further studies are warranted to define the exact target structures of AECA in SuS
MOG-IgG in NMO and related disorders: a multicenter study of 50 patients. Part 3: Brainstem involvement - frequency, presentation and outcome
Background
Myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) are present in a subset of aquaporin-4 (AQP4)-IgG-negative patients with optic neuritis (ON) and/or myelitis. Little is known so far about brainstem involvement in MOG-IgG-positive patients.
Objective
To investigate the frequency, clinical and paraclinical features, course, outcome, and prognostic implications of brainstem involvement in MOG-IgG-positive ON and/or myelitis.
Methods
Retrospective case study.
Results
Among 50 patients with MOG-IgG-positive ON and/or myelitis, 15 (30 %) with a history of brainstem encephalitis were identified. All were negative for AQP4-IgG. Symptoms included respiratory insufficiency, intractable nausea and vomiting (INV), dysarthria, dysphagia, impaired cough reflex, oculomotor nerve palsy and diplopia, nystagmus, internuclear ophthalmoplegia (INO), facial nerve paresis, trigeminal hypesthesia/dysesthesia, vertigo, hearing loss, balance difficulties, and gait and limb ataxia; brainstem involvement was asymptomatic in three cases. Brainstem inflammation was already present at or very shortly after disease onset in 7/15 (47 %) patients. 16/21 (76.2 %) brainstem attacks were accompanied by acute myelitis and/or ON. Lesions were located in the pons (11/13), medulla oblongata (8/14), mesencephalon (cerebral peduncles; 2/14), and cerebellar peduncles (5/14), were adjacent to the fourth ventricle in 2/12, and periaqueductal in 1/12; some had concomitant diencephalic (2/13) or cerebellar lesions (1/14). MRI or laboratory signs of blood-brain barrier damage were present in 5/12. Cerebrospinal fluid pleocytosis was found in 11/14 cases, with neutrophils in 7/11 (3-34 % of all CSF white blood cells), and oligoclonal bands in 4/14. Attacks were preceded by acute infection or vaccination in 5/15 (33.3 %). A history of teratoma was noted in one case. The disease followed a relapsing course in 13/15 (87 %); the brainstem was involved more than once in 6. Immunosuppression was not always effective in preventing relapses. Interferon-beta was followed by new attacks in two patients. While one patient died from central hypoventilation, partial or complete recovery was achieved in the remainder following treatment with high-dose steroids and/or plasma exchange. Brainstem involvement was associated with a more aggressive general disease course (higher relapse rate, more myelitis attacks, more frequently supratentorial brain lesions, worse EDSS at last follow-up).
Conclusions
Brainstem involvement is present in around one third of MOG-IgG-positive patients with ON and/or myelitis. Clinical manifestations are diverse and may include symptoms typically seen in AQP4-IgG-positive neuromyelitis optica, such as INV and respiratory insufficiency, or in multiple sclerosis, such as INO. As MOG-IgG-positive brainstem encephalitis may take a serious or even fatal course, particular attention should be paid to signs or symptoms of additional brainstem involvement in patients presenting with MOG-IgG-positive ON and/or myelitis
Inositol 1,4,5-trisphosphate receptor type 1 autoantibodies in paraneoplastic and non-paraneoplastic peripheral neuropathy
Background: Recently, we described a novel autoantibody, anti-Sj/ITPR1-IgG, that targets the inositol 1,4,5-trisphosphate receptor type 1 (ITPR1) in patients with cerebellar ataxia. However, ITPR1 is expressed not only by Purkinje cells but also in the anterior horn of the spinal cord, in the substantia gelatinosa and in the motor, sensory (including the dorsal root ganglia) and autonomic peripheral nervous system, suggesting that the clinical spectrum associated with autoimmunity to ITPR1 may be broader than initially thought. Here we report on serum autoantibodies to ITPR1 (up to 1:15,000) in three patients with (radiculo)polyneuropathy, which in two cases was associated with cancer (ITPR1-expressing adenocarcinoma of the lung, multiple myeloma), suggesting a paraneoplastic aetiology. Methods: Serological and other immunological studies, and retrospective analysis of patient records. Results: The clinical findings comprised motor, sensory (including severe pain) and autonomic symptoms. While one patient presented with subacute symptoms mimicking Guillain-Barré syndrome (GBS), the symptoms progressed slowly in two other patients. Electrophysiology revealed delayed F waves; a decrease in motor and sensory action potentials and conduction velocities; delayed motor latencies; signs of denervation, indicating sensorimotor radiculopolyneuropathy of the mixed type; and no conduction blocks. ITPR1-IgG belonged to the complement-activating IgG1 subclass in the severely affected patient but exclusively to the IgG2 subclass in the two more mildly affected patients. Cerebrospinal fluid ITPR1-IgG was found to be of predominantly extrathecal origin. A 3H-thymidine-based proliferation assay confirmed the presence of ITPR1-reactive lymphocytes among peripheral blood mononuclear cells (PBMCs). Immunophenotypic profiling of PBMCs protein demonstrated predominant proliferation of B cells, CD4 T cells and CD8 memory T cells following stimulation with purified ITPR1 protein. Patient ITPR1-IgG bound both to peripheral nervous tissue and to lung tumour tissue. A nerve biopsy showed lymphocyte infiltration (including cytotoxic CD8 cells), oedema, marked axonal loss and myelin-positive macrophages, indicating florid inflammation. ITPR1-IgG serum titres declined following tumour removal, paralleled by clinical stabilization. Conclusions: Our findings expand the spectrum of clinical syndromes associated with ITPR1-IgG and suggest that autoimmunity to ITPR1 may underlie peripheral nervous system diseases (including GBS) in some patients and may be of paraneoplastic origin in a subset of cases
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