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Background: Factor (F)XI deficiency is a rare bleeding disorder with a poor correlation between bleeding tendency and FXI level. Management of pregnant women with FXI deficiency is not clearly established, especially regarding neuraxial analgesia (NA). Objectives: A retrospective multicenter observational study was conducted in French hemostasis centers on pregnant women with FXI of <60 IU/dL. Methods: Data to report were (i) FXI levels before pregnancy and at time of delivery, (ii) type of NA and delivery management modalities, and (iii) possible complications related to NA and bleeding complications. Results: Three hundred fourteen pregnancies in patients with FXI deficiency of <60 IU/dL were reported (from 20 centers); among them, 199 NA procedures have been completed (137 epidurals and 61 spinals, 1 had both). The period of childbirth was mostly from 2014 to 2020 (281/314; 89.5%). Congenital FXI deficiency was established with certainty by investigators in 32.8% patients (n = 103). Previous bleedings were described in 20.4% of the patients (64/314; 45.3% cutaneous, 31.3% gynecologic, and 15.6% postsurgical). Thirteen deliveries had an NA procedure with FXI of <30 IU/dL, 42 with FXI of 30-40 IU/dL, and 118 with FXI of 40-60 IU/dL. Median FXI levels at delivery in the epidural and spinal groups were not significantly different but were significantly lower in the group without NA by medical staff contraindications. There were no complications related to NA. A 17.5% postpartum hemorrhage or excessive postpartum bleeding incidence was reported, which is consistent with previous data. Conclusion: Our data support the use of a 30 IU/dL FXI threshold for NA, as suggested by the French proposals published in August 2023.
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Amyotrophic lateral sclerosis (ALS) is a rare fatal motor neuron disease. Although many potential mechanisms have been proposed, the pathophysiology of the disease remains unknown. Currently available treatments can only delay the progression of the disease and prolong life expectancy by a few months. There is still no definitive cure for ALS, and the development of new treatments is limited by a lack of understanding of the underlying biological processes that trigger and promote neurodegeneration. Several scientific results suggest a neurovascular impairment in ALS providing perspectives for the development of new biomarkers and treatments. In this article, we performed a systematic review using PRISMA guidelines including PubMed, EmBase, GoogleScholar, and Web of Science Core Collection to analyze the scientific literature published between 2000 and 2021 discussing the neurocardiovascular involvement and ophthalmologic abnormalities in ALS. In total, 122 articles were included to establish this systematic review. Indeed, microvascular pathology seems to be involved in ALS, affecting all the neurovascular unit components. Retinal changes have also been recently highlighted without significant alteration of the visual pathways. Despite the peripheral location of the retina, it is considered as an extension of the central nervous system (CNS) as it displays similarities to the brain, the inner blood-retinal barrier, and the blood-brain barrier. This suggests that the eye could be considered as a 'window' into the brain in many CNS disorders. Thus, studying ocular manifestations of brain pathologies seems very promising in understanding neurodegenerative disorders, mainly ALS. Optical coherence tomography angiography (OCT-A) could therefore be a powerful approach for exploration of retinal microvascularization allowing to obtain new diagnostic and prognostic biomarkers of ALS.
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Esclerosis Amiotrófica Lateral , Microvasos , Vasos Retinianos , Tomografía de Coherencia Óptica , Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Esclerosis Amiotrófica Lateral/fisiopatología , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/fisiopatología , Humanos , Microvasos/diagnóstico por imagen , Microvasos/fisiopatología , Angiografía/métodos , Movimientos SacádicosRESUMEN
BACKGROUND: The ISTH-SSC guidelines for lupus anticoagulant (LA) testing recommend using in-house determined cut-off values, pooled normal plasma (PNP) for ratio normalization, and a ratio for the mixing test interpretation. They strongly support the mixing step role in the diagnostic process. OBJECTIVES: To investigate and compare the LA testing results and interpretations obtained following the ISTH-SSC guidelines or the available alternatives. PATIENTS/METHODS: Blood samples for LA testing from 462 consecutive patients were evaluated for screening, mixing and confirmatory tests. The analysis focused on the interpretation differences between using (1) the in-house cut-off values versus the manufacturer's cut-off values, (2) a normalized ratio calculated using PNP at each run versus the mean of the reference interval, (3) a normalized ratio versus the index of circulating anticoagulant to interpret the mixing step, and (4) a two-step versus three-step procedure. RESULTS: LA testing outcomes were comparable when using the in-house and manufacturer's cut-off values. More positive dilute Russell's viper venom (DRVV) time results were obtained with the normalized ratio based on PNP than with the mean of the reference interval. Overall, the mixing test results obtained with the normalized ratio and the index of circulating anticoagulant showed a good agreement. Among the 97 DRVV Screen test-positive samples, 33 and 89 were classified as LA-positive with the 3-step and the 2-step procedure, respectively. CONCLUSIONS: The cut-off value used and the way to normalize ratios had a limited impact. Conversely, it is important to understand the mixing test characteristics to maximize its diagnostic potential.
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Síndrome Antifosfolípido , Inhibidor de Coagulación del Lupus , Humanos , Pruebas de Coagulación Sanguínea/métodos , Tiempo de Protrombina , Anticoagulantes/uso terapéutico , Tiempo de Tromboplastina ParcialRESUMEN
Three-dimensional (3D) imaging offers new possibilities in animal phenotyping. Here, we investigated how this technology can be used to study the morphological changes that occur in dairy cows over the course of a single lactation. First, we estimated the individual body weight (BW) of dairy cows using traits measured with 3D images. To improve the quality of prediction, we monitored body growth (via 3D imaging), gut fill (via individual dry matter intake), and body reserves (via body condition score) throughout lactation. A group of 16 Holstein cows-8 in their first lactation, 4 in their second lactation, and 4 in their third or higher lactation-was scanned in 3D once a month for an entire lactation. Values of morphological traits (e.g., chest depth or hip width) increased continuously with parity, but cows in their first lactation experienced the largest increase during the monitoring period. Values of partial volume, estimated from point of shoulder to pin bone, predicted BW with an error of 25.4 kg (R2 = 0.92), which was reduced to 14.3 kg when the individual effect of cows was added to the estimation model. The model was further improved by the addition of partial surface area (from point of shoulder to pin bone), hip width, chest depth, diagonal length, and heart girth, which increased the R2 of BW prediction to 0.94 and decreased root mean square error to 22.1 kg. The different slopes for individual cows were partly explained by body condition score and morphological traits, indicating that they may have reflected differences in body density among animals. Changes in BW over the course of lactation were mostly due to changes in growth, which accounted for around two-thirds of BW gain regardless of parity. Body reserves and gut fill had smaller but still notable effects on body composition, with a higher gain in body reserves and gut fill for cows in their first lactation compared with multiparous cows. This work demonstrated the potential for rapid and low-cost 3D imaging to facilitate the monitoring of several traits of high interest in dairy livestock farming.
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Alimentación Animal , Leche , Alimentación Animal/análisis , Animales , Peso Corporal , Bovinos , Femenino , Imagenología Tridimensional/veterinaria , Lactancia , EmbarazoRESUMEN
INTRODUCTION: Chronic neutrophilic leukemia (CNL) is a rare myeloproliferative syndrome characterized by a significant increase in mature neutrophils. One of the most serious complications is the occurrence of bleeding events, which may sometimes lead to death. CASE REPORT: A 75-year-old patient presented with CNL, complicated by a severe bleeding phenotype. Biological investigations revealed platelet function defect and increase in neutrophil elastase. The follow-up was marked by an intracranial hemorrhage leading to the patient's death 7â¯months after diagnosis. CONCLUSION: This bleeding phenotype has been reported several times in patients with CNL. However, the pathophysiological mechanisms that cause bleeding are not yet fully understood.
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Hemorragia Cerebral/etiología , Leucemia Neutrofílica Crónica/complicaciones , Anciano , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/patología , Resultado Fatal , Humanos , Leucemia Neutrofílica Crónica/diagnóstico , Leucemia Neutrofílica Crónica/patología , Masculino , Agregación PlaquetariaRESUMEN
Second-order optical nonlinearities can be greatly enhanced by orders of magnitude in resonantly excited nanostructures. These resonant nonlinearities continually attract attention, particularly in newly discovered materials. However, they are frequently not as heightened as currently predicted, limiting their exploitation in nanostructured nonlinear optics. Here, we present a clear-cut theoretical and experimental demonstration that the second-order nonlinear susceptibility can vary by orders of magnitude as a result of giant destructive, as well as constructive, interference effects in complex systems. Using terahertz quantum cascade lasers as a model source to investigate interband and intersubband nonlinearities, we show that these giant interferences are a result of an unexpected interplay of the second-order nonlinear contributions of multiple light and heavy hole states. As well as of importance to understand and engineer the resonant optical properties of nanostructures, this advanced framework can be used as a novel, sensitive tool to elucidate the band structure properties of complex materials.
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GnpIS is a data repository for plant phenomics that stores whole field and greenhouse experimental data including environment measures. It allows long-term access to datasets following the FAIR principles: Findable, Accessible, Interoperable, and Reusable, by using a flexible and original approach. It is based on a generic and ontology driven data model and an innovative software architecture that uncouples data integration, storage, and querying. It takes advantage of international standards including the Crop Ontology, MIAPPE, and the Breeding API. GnpIS allows handling data for a wide range of species and experiment types, including multiannual perennial plants experimental network or annual plant trials with either raw data, i.e., direct measures, or computed traits. It also ensures the integration and the interoperability among phenotyping datasets and with genotyping data. This is achieved through a careful curation and annotation of the key resources conducted in close collaboration with the communities providing data. Our repository follows the Open Science data publication principles by ensuring citability of each dataset. Finally, GnpIS compliance with international standards enables its interoperability with other data repositories hence allowing data links between phenotype and other data types. GnpIS can therefore contribute to emerging international federations of information systems.
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BACKGROUND: According to the International Society on Thrombosis and Haemostasis (ISTH), intramuscular hematoma without other severity criteria is not considered a major bleeding. OBJECTIVES: In a large cohort of reversed vitamin K antagonist (VKA) patients admitted to the emergency unit for muscular hematoma, we assess frequency, severity, and anticoagulation management based on whether ISTH criteria were met or not. MATERIALS AND METHODS: We performed a retrospective single-center study involving patients admitted to an emergency unit for VKA-induced intramuscular hematoma whose bleeding was reversed with prothrombin complex concentrates. RESULTS: During the study period, 631 VKA-induced bleeding events occurred in our emergency unit, of which 73 (11.6%) were intramuscular hematomas and half met ISTH criteria. The mean age was 75.5years (95% CI=72.6-78.3). Admission blood tests showed that patients with ISTH criteria had higher international normalized ratio (7.0±4.6 vs. 4.1±3.0, p=0.002) and lower hemoglobin (8.1±1.8 vs. 11.9±2.2, p<0.001) than those without. Patients with ISTH criteria were more likely to have intramuscular hematoma in the iliopsoas, gluteal, and pectoral muscles than those without. Interestingly, two-thirds of rectus sheath hematomas involved patients without ISTH criteria. However, patients with or without ISTH criteria exhibited a similar hospitalization duration and rate of re-bleeding. CONCLUSION: We showed that half of the patients admitted with intramuscular hematoma could not be qualified as having ISTH-criteria major bleeding. Interestingly, these patients displayed a similar hospitalization duration and rate of re-bleeding to those with ISTH-criteria major bleeding.
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Anticoagulantes/efectos adversos , Factores de Coagulación Sanguínea/uso terapéutico , Servicio de Urgencia en Hospital , Hematoma/inducido químicamente , Pacientes Internos , Enfermedades Musculares/inducido químicamente , Vitamina K/antagonistas & inhibidores , Anciano , Femenino , Estudios de Seguimiento , Hematoma/diagnóstico , Hematoma/terapia , Humanos , Masculino , Enfermedades Musculares/diagnóstico , Enfermedades Musculares/terapia , Pronóstico , Estudios RetrospectivosRESUMEN
Essentials The role of increased factor VIII in cirrhosis-induced hypercoagulability has never been demonstrated. Factor VIII and protein C effects were characterized by thrombin generation with thrombomodulin. Factor VIII elevation plays a significant role in cirrhosis-induced plasma hypercoagulability. Only protein C and factor VIII normalization led to thrombin generation similar to controls. SUMMARY: Background In cirrhosis, thrombin generation (TG) studied in the presence of thrombomodulin (TM) indicates plasma hypercoagulability. Although the role of protein C (PC) deficiency has been investigated, the influence of an increase in the factor VIII level has never been addressed. Objectives We investigated the roles of high FVIII and low PC levels in increased TG in the presence of TM. Methods Blood samples were prospectively collected from 35 healthy controls and 93 patients with cirrhosis (Child-Turcotte-Pugh [CTP]-A, n = 61; CTP-B, n = 19; and CTP-C, n = 13) and FVIII levels > 150% (n = 48) and/or PC levels < 70% (n = 88). TG was performed with tissue factor (5 pm), phospholipids, and TM (4 nm). FVIII and PC levels were normalized by adding an inhibitory anti-FVIII antibody and exogenous PC, respectively. Results The endogenous thrombin potential (ETP) in the presence of TM was higher in patients than in controls. After FVIII normalization, the ETP (median) decreased from 929 nm min to 621 nm min (CTP-A), 1122 nm min to 1082 nm min (CTP-B), and 1221 nm min to 1143 nm min (CTP-C); after PC normalization, it decreased from 776 nm min to 566 nm min (CTP-A), 1120 nm min to 790 nm min (CTP-B), and 995 nm min to 790 nm min (CTP-C). The ETP was reduced by 17% and 30%, respectively, but normal TG was not restored. When both FVIII and PC levels were normalized, the ETP decreased from 929 nm min to 340 nm min (CTP-A), 1122 nm min to 506 nm min (CTP-B), and 1226 nm min to 586 nm min (CTP-C), becoming similar to control levels. Conclusion Cirrhosis-induced plasma hypercoagulability, as demonstrated in these experimental conditions, can be partly explained by opposite changes in two factors: PC level (decrease) and FVIII level (increase).
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Coagulación Sanguínea , Factor VIII/metabolismo , Cirrosis Hepática/complicaciones , Trombofilia/etiología , Adulto , Anciano , Biomarcadores/sangre , Pruebas de Coagulación Sanguínea , Estudios de Casos y Controles , Femenino , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/diagnóstico , Masculino , Persona de Mediana Edad , Fenotipo , Proteína C/metabolismo , Trombina/metabolismo , Trombomodulina/metabolismo , Trombofilia/sangre , Trombofilia/diagnóstico , Regulación hacia ArribaAsunto(s)
Factor VIII/uso terapéutico , Hemofilia A/tratamiento farmacológico , Proteínas Recombinantes/uso terapéutico , Factor VIII/efectos adversos , Francia , Humanos , Isoanticuerpos/efectos adversos , Isoanticuerpos/inmunología , Ensayos Clínicos Controlados Aleatorios como Asunto , Proteínas Recombinantes/efectos adversos , Resultado del TratamientoRESUMEN
Phytophthora root rot, caused by Phytophthora sojae, is one of the most damaging diseases of soybean and the introgression of Rps (Resistance to P. sojae) genes into elite soybean lines is arguably the best way to manage this disease. Current bioassays to phenotype the gene-for-gene relationship are hampered with respect to reproducibility and long-term stability of isolates, and do not accurately predict horizontal resistance individually. The aim of our study was to investigate a new way of phenotyping P. sojae isolates and vertical and horizontal resistance in soybean that relies on zoospores inoculated directly into a hydroponic system. Inoculation of P. sojae isolates against a set of eight differentials accurately and reproducibly identified pathotypes over a period of two years. When applied to test vertical resistance of soybean lines with known and unknown Rps genes, the bioassay relied on plant dry weight to correctly identify all genes. In addition, simultaneous inoculations of three P. sojae isolates, collectively carrying eight major virulence factors against 64 soybean lines with known and unknown levels of horizontal resistance, separated the plants into five distinct groups of root rot, allowing the discrimination of lines with various degrees of partial resistance. Based on those results, this bioassay offers several advantages in facilitating efforts in breeding soybean for P. sojae resistance and in identifying virulence factors in P. sojae.
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Bioensayo/métodos , Resistencia a la Enfermedad , Glycine max/genética , Hidroponía/métodos , Phytophthora/fisiología , Enfermedades de las Plantas/microbiología , FenotipoRESUMEN
Mid-infrared (MIR) sideband generation on a near infrared (NIR) optical carrier is demonstrated within a quantum cascade laser (QCL). By employing an externally injected NIR beam, E(NIR), that is resonant with the interband transitions of the quantum wells in the QCL, the nonlinear susceptibility is enhanced, leading to both frequency mixing and sideband generation. A GaAs-based MIR QCL (E(QCL) = 135 meV) with an aluminum-reinforced waveguide was utilized to overlap the NIR and MIR modes with the optical nonlinearity of the active region. The resulting difference sideband (E(NIR) - E(QCL)) shows a resonant behavior as a function of NIR pump wavelength and a maximum second order nonlinear susceptibility, χ((2)), of ~1 nm/V was obtained. Further, the sideband intensity showed little dependence with the operating temperature of the QCL, allowing sideband generation to be realized at room temperature.
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INTRODUCTION: Direct oral anticoagulants are a recent alternative to vitamin K antagonists but there is a lack of data regarding patients receiving these new types of treatment. The aim of the study was to identify and describe patients receiving direct oral anticoagulants admitted to an emergency unit. METHODS: All the patients taking direct oral anticoagulants, admitted to the emergency room of the Clermont-Ferrand Hospital from January to August 2013, were included in this retrospective and descriptive study. RESULTS: Among the 73 patients included, 47.9% were treated with dabigatran and 52.1% with rivaroxaban. The indication was stroke prevention in 62 patients with atrial fibrillation whose average CHADS2 score was 2.6 [2.3-3](IC95%). The average age was 76.4 years [73.7-79.1](IC95%). Twenty-nine patients (39.7%) had at least one drug association known for increasing the risk of bleeding. Average scores for bleeding risk were: HAS-BLED 3.1 [2.9-3.3](IC95%) and Beyth 1.5 [1.3-1.6](IC95%). Bleeding patients included a higher percentage of men (68.8 vs. 38.2%, P=0.032). Creatinine clearance was lower in patients with major bleeding (45.2% vs. 68.8 mL/min, P=0.002). The Beyth score was highest in both sub-groups. CONCLUSION: In our study, we have found that the bleeding risk factors were: male gender, a high Beyth score, and a lowered creatinine clearance. Overall, patients treated with direct oral anticoagulants admitted to the emergency room were old with many co-morbidities, especially cardiovascular conditions; polymedication was frequent.
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Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Servicio de Urgencia en Hospital , Hemorragia/epidemiología , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/tratamiento farmacológico , Bencimidazoles/administración & dosificación , Bencimidazoles/efectos adversos , Dabigatrán , Interacciones Farmacológicas , Femenino , Francia/epidemiología , Hemorragia/inducido químicamente , Historia Antigua , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Morfolinas/administración & dosificación , Morfolinas/efectos adversos , Estudios Retrospectivos , Factores de Riesgo , Rivaroxabán , Accidente Cerebrovascular/prevención & control , Tiofenos/administración & dosificación , Tiofenos/efectos adversos , beta-Alanina/administración & dosificación , beta-Alanina/efectos adversos , beta-Alanina/análogos & derivadosRESUMEN
Development of antibodies (Abs) against factor VIII (FVIII) is a severe complication of haemophilia A treatment. Recent publications suggest that domain specificity of anti-FVIII antibodies, particularly during immune tolerance induction (ITI), might be related to the outcome of the treatment. Obtaining suitable tools for a fine mapping of discontinuous epitopes could thus be helpful. The aim of this study was to map discontinuous epitopes on FVIII A2 domain using a new epitope prediction functionality of the PEPOP bioinformatics tool and a peptide inhibition assay based on the Luminex technology. We predicted, selected and synthesized 40 peptides mimicking discontinuous epitopes on the A2 domain of FVIII. A new inhibition assays using Luminex technology was performed to identify peptides able to inhibit the binding of anti-A2 Abs to A2 domain. We identified two peptides (IFKKLYHVWTKEVG and LYSRRLPKGVKHFD) able to block the binding of anti-A2 allo-antibodies to this domain. The three-dimensional representation of these two peptides on the A2 domain revealed that they are localized on a limited region of A2. We also confirmed that residues 484-508 of the A2 domain define an antigenic site. We suggest that dissection of the antibody response during ITI using synthetic peptide epitopes could provide important information for the management of patients with inhibitors.
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Simulación por Computador , Mapeo Epitopo , Epítopos/química , Factor VIII/química , Modelos Moleculares , Péptidos/química , Dominios y Motivos de Interacción de Proteínas , Algoritmos , Secuencia de Aminoácidos , Inhibidores de Factor de Coagulación Sanguínea/inmunología , Inhibidores de Factor de Coagulación Sanguínea/metabolismo , Epítopos/inmunología , Epítopos/metabolismo , Factor VIII/inmunología , Factor VIII/metabolismo , Hemofilia A/tratamiento farmacológico , Hemofilia A/inmunología , Humanos , Isoanticuerpos/inmunología , Isoanticuerpos/metabolismo , Péptidos/síntesis química , Péptidos/inmunología , Péptidos/metabolismo , Unión Proteica , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas/inmunologíaRESUMEN
OBJECTIVES: To describe management and screening for high-risk patients concerning post-partum hemorrhage (PPH) and antenatal management for severe anemia, thrombopenia, bleeding disorders and anticoagulant therapy. METHODS: Bibliographic search restricted to French and English languages using Medline database and recommendations of medical societies. RESULTS: The appropriate place for delivery should be chosen after multidisciplinary concertation based on level of risk (especially past-history of severe PPH and bleeding disorder) and easy access to blood products (Professional Consensus). Prevention for severe anemia is mainly based on oral iron supplementation (grade B). Explorations are required in case of thrombopenia<100Giga/L (grade C). Patients with bleeding disorder require the assistance of a physician skilled in hemostasis for perinatal management (grade C). Preventive anticoagulant therapy has no impact on PPH risk and perimedullar analgesia is usually authorized 12hours after last injection (grade C). Curative anticoagulant therapy slightly increases PPH risk and perimedullar analgesia is authorized only after 24hours since last injection (Professional Consensus). CONCLUSION: Prenatal identification of high-risk patients concerning PPH implies multidisciplinary concertation to determine the most appropriate birthplace where technical and human resources are available.
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Complicaciones del Trabajo de Parto/terapia , Enfermedades Placentarias/terapia , Hemorragia Posparto/prevención & control , Femenino , Humanos , Complicaciones del Trabajo de Parto/diagnóstico , Complicaciones del Trabajo de Parto/prevención & control , Enfermedades Placentarias/diagnóstico , Hemorragia Posparto/diagnóstico , EmbarazoAsunto(s)
Anticuerpos/inmunología , Factor VIII/inmunología , Hemofilia A/sangre , Hemofilia A/inmunología , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/sangre , Anticuerpos/sangre , Inhibidores de Factor de Coagulación Sanguínea/sangre , Inhibidores de Factor de Coagulación Sanguínea/inmunología , Factor VIII/uso terapéutico , Hemofilia A/diagnóstico , Hemofilia A/tratamiento farmacológico , Humanos , Isoanticuerpos/sangre , Isoanticuerpos/inmunología , Masculino , PronósticoRESUMEN
We present a novel experimental technique that can differentiate unequivocally between chaotic light and coherent light with amplitude fluctuations, and thus permits us to characterize unambiguously the output of a laser. This technique consists of measuring the second-order intensity cross correlation at the outputs of an unbalanced Michelson interferometer. It is applied to a chaotic light source and to the output of a semiconductor nanolaser whose "standard" intensity correlation function above threshold displays values compatible with a mixture of coherent and chaotic light. Our experimental results demonstrate that the output of such lasers is not partially chaotic but is indeed a coherent state with amplitude fluctuations.
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Antibodies (inhibitors and non-neutralising antibodies [NNA]) directed against factor VIII (FVIII) remain the main iatrogenic complication in haemophilia A (HA) patients. Inhibitors reduce FVIII pro-coagulant properties, whereas NNA are directed against non-functional epitopes. NNA are poorly studied and their prevalence, epitope specificity and physiopathology inadequately defined. The aim of this study was first to evaluate NNA prevalence in a French retrospective multicentric series of 210 patients without inhibitors, then to determine their epitope specificity (against the heavy chain [HC] or the light chain [LC] of FVIII) and particularly to assess the prevalence of anti-B domain NNA using specifically designed x-MAP assays. NNA occurred in 18.1% of patients (38/210) and their prevalence was not influenced by the severity of the disease. Among the 38 patients with NNA, 73.7% had anti-FVIII Abs against the HC, 13.2% against the LC and 13.2% had anti-FVIII Abs against both chains. There is thus a clear immuno-dominance of the HC of FVIII in the epitope profile of NNA, whatever the severity of HA. The proportion of NNA that recognised the B domain was 18.4% (n=7/38). A multivariate analysis did not highlight differences in NNA occurrence between patients treated with recombinant FVIII or with plasma- derived FVIII (19.6% vs. 14.9%, p=0.53).
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Anticuerpos/metabolismo , Epítopos/metabolismo , Factor VIII/metabolismo , Hemofilia A/inmunología , Epítopos Inmunodominantes/metabolismo , Adolescente , Adulto , Anciano , Niño , Preescolar , Progresión de la Enfermedad , Mapeo Epitopo , Factor VIII/inmunología , Femenino , Francia , Hemofilia A/epidemiología , Hemofilia A/fisiopatología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Prevalencia , Estudios RetrospectivosRESUMEN
A new method of urinary oligosaccharides identification by matrix-assisted laser desorption time-of-flight mass spectrometry is presented. The method involves three steps: coupling of the urinary oligosaccharides with 8-aminonaphthalene-1,3,6-trisulfonic acid; fast purification over a porous graphite carbon extraction column; and mass spectrometric analysis. Identification of urinary oligosaccharides is based on the patterns and values of the pseudomolecular ions observed. We report here the patterns in urines from patients with Pompe disease, alpha and beta mannosidoses, galacto-sialidosis, and GM1 gangliosidosis. The protocols described here allowed facile and sensitive identification of the pathognomonic oligosacchariduria present in lysosomal diseases and can be extended to any pathological oligosacchariduria.