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BACKGROUND: Acral pustular disease within the pustular psoriasis/psoriasis-like spectrum mainly includes palmoplantar pustulosis (PPP) and acrodermatitis continua of Hallopeau (ACH). Scarce data argue for a distinction between these two entities, but no study has compared the clinical and epidemiologic characteristics of ACH and PPP. OBJECTIVES: We aimed to perform a comparative description of the epidemiological and clinical characteristics of PPP and ACH in a multicentre retrospective cohort. METHODS: In this multicentre national retrospective cohort study, we compared the epidemiological characteristics, comorbidities and psoriasis characteristics of patients with PPP and ACH. RESULTS: A total of 234 patients were included: 203 (87%) with PPP, 18 (8%) with ACH and 13 (6%) with both, according to 2017 ERASPEN criteria. As compared with ACH, PPP was associated with female sex, smoking activity and higher median BMI (P = 0.01, P = 0.02 and P = 0.05 respectively). A family background of psoriasis was more frequent in PPP than ACH. Age of onset of palmoplantar disease was similar between PPP and ACH patients, median age 44 and 48 years respectively. Peripheral joint inflammatory involvement was the only rheumatic disease associated with ACH. The association with another psoriasis type was similar in PPP and ACH (57.6% and 61.1% respectively). CONCLUSION: Our study confirms in a large PPP cohort the predominance of females and a high prevalence of smoking and elevated body mass index but also shows an association of these features in PPP as compared with ACH. In addition, it highlights peripheral arthritis as the only arthritis endotype associated with ACH. Increased knowledge of the immunogenetic backgrounds underlying these two entities is warranted to better stratify pustular psoriasis or psoriasis-like entities for precision medicine.
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Acrodermatitis , Artritis , Enfermedades de Inmunodeficiencia Primaria , Psoriasis , Enfermedades Cutáneas Vesiculoampollosas , Acrodermatitis/epidemiología , Adulto , Demografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psoriasis/epidemiología , Estudios RetrospectivosRESUMEN
BACKGROUND: Palmoplantar pustulosis (PPP) and acrodermatitis continua of Hallopeau (ACH) are rare variants of psoriasis. Knowledge of the efficacy of biologics is scarce. OBJECTIVES: To evaluate the real-life efficacy of tumour necrosis factor blockers and ustekinumab in PPP and in ACH. METHODS: A multicentre retrospective descriptive study was conducted in 19 dermatology departments, including all patients with PPP or ACH seen from 2014 to 2016 who received one of the studied biologics. The data were collected by a standardized document. Factors associated with complete clearance (CC) were analysed by multivariate analysis, estimating odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among 92 patients included, 50 received adalimumab, 44 ustekinumab, 36 etanercept and 31 infliximab. Improvement and CC were observed in 83.9% and 20.0% patients receiving infliximab, 75.0% and 38.6% ustekinumab, 57.1% and 20.0% etanercept and 60.4% and 29.2% adalimumab. We found no significant difference in CC rates or duration of treatment among the biological treatments (P = 0.18 and P = 0.10, respectively). On multivariate analysis, CC with etanercept was associated with the ACH form and not smoking [OR = 9.5 (95% CI 1.1-82.7), P = 0.04 and 0.1 (0.01-0.9), P = 0.04]; with ustekinumab, male sex and absence of obesity [6.0 (1.3-28.6), P = 0.02 and 4.7 (1.0-22.7), P = 0.05]; with adalimumab, the ACH form [11.9 (2.7-52.3), P = 0.001]; and with infliximab, obesity [5.6 (1.1-29.4), P = 0.04]. CONCLUSIONS: We found no difference in efficacy between TNF blockers and ustekinumab and among the three different TNF blockers in real life for PPP or ACH, which reveals the heterogeneity of clinical response to biologics in pustular psoriasis as compared with plaque psoriasis.
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Acrodermatitis , Psoriasis , Acrodermatitis/tratamiento farmacológico , Adalimumab , Etanercept , Humanos , Infliximab , Masculino , Psoriasis/tratamiento farmacológico , Estudios Retrospectivos , Inhibidores del Factor de Necrosis Tumoral , UstekinumabRESUMEN
Neuroimaging is critical for the diagnosis of neonatal arterial ischemic stroke (NAIS) and for prognosis estimation. The purpose of this work is to define guidelines of clinical neuroimaging for the diagnosis of NAIS, for the optimization of the imaging timing and for the assessment of the prognostic value of each imaging technique. A systematic search of electronic databases (Medline via Pubmed) for studies whose title and abstract were focused on NAIS has been conducted. One hundred and ten articles were selected and their results were analyzed by three Senior Practitioners of pediatric radiology using common methodology for guidelines elaboration within the group of experts gathered by Scientific Societies in the field. MRI with a diffu si on-weighted sequence (DWI) and T1, T2, and T2*-weighted sequences must be performed in the case of suspected NAIS (no sedation is required). In the first hours after the injury, an acute ischemic lesion is characterized by a hypersignal on the diffusion-weighted sequence, with a decrease of the apparent coefficient of diffusion (ADC). The best time to evaluate the extent of the ischemic lesion is between day 2 and day 4 after injury, when the ADC decrease reaches its nadir. In the acute phase, US may be useful as first imaging at the bedside to exclude other pathologies like large space-occupying hemorrhages, but its specific added value on NAIS diagnosis or prognosis assessment is very low. CT scan has no added value in NAIS, compared to MRI. Motor outcome is correlated with the extent of the lesion and with the presence of a definite injury of the corticospinal tract, which is well seen on the diffusion sequence at the acute stage. A secondary atrophy within the mesencephalon (cerebral peduncles) is tied in with a high risk of hemiplegia. Visual outcome is more often compromised in the case of lesions of the posterior cerebral artery territory.
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Isquemia Encefálica/diagnóstico por imagen , Neuroimagen/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Humanos , Recién Nacido , Guías de Práctica Clínica como AsuntoRESUMEN
Neonatal arterial ischemic stroke (NAIS) is a rare event that occurs in approximately one in 5000 term or close-to-term infants. Most affected infants will present with seizures. Although a well-recognized clinical entity, many questions remain regarding diagnosis, risk factors, treatment, and follow-up modalities. In the absence of a known pathophysiological mechanism and lack of evidence-based guidelines, only supportive care is currently provided. To address these issues, a French national committee set up by the French Neonatal Society (Société française de néonatologie) and the national referral center (Centre national de référence) for arterial ischemic stroke in children drew up guidelines based on an HAS (Haute Autorité de santé [HAS]; French national authority for health) methodology. The main findings and recommendations established by the study group are: (1) among the risk factors, male sex, primiparity, caesarean section, perinatal hypoxia, and fetal/neonatal infection (mainly bacterial meningitis) seem to be the most frequent. As for guidelines, the study group recommends the following: (1) the transfer of neonates with suspected NAIS to a neonatal intensive care unit with available equipment to establish a reliable diagnosis with MRI imaging and neurophysiological monitoring, preferably by continuous video EEG; (2) acute treatment of suspected infection or other life-threatening processes should be addressed immediately by the primary medical team. Persistent seizures should be treated with a loading dose of phenobarbital 20mg/kg i.v.; (3) MRI of the brain is considered optimal for the diagnosis of NAIS. Diffusion-weighted imaging with apparent diffusion coefficient is considered the most sensitive measure for identifying infarct in the neonatal brain. The location and extent of the lesions are best assessed between 2 and 4 days after the onset of stroke; (4) routine testing for thrombophilia (AT, PC PS deficiency, FV Leiden or FII20210A) or for detecting other biological risk factors such as antiphospholipid antibodies, high FVIII, homocysteinemia, the Lp(a) test, the MTHFR thermolabile variant should not be considered in neonates with NAIS. Testing for FV Leiden can be performed only in case of a documented family history of venous thromboembolic disease. Testing neonates for the presence of antiphospholipid antibodies should be considered only in case of clinical events arguing in favor of antiphospholipid syndrome in the mother; (5) unlike childhood arterial ischemic stroke, NAIS has a low 5-year recurrence rate (approximately 1 %), except in those children with congenital heart disease or multiple genetic thrombophilia. Therefore, initiation of anticoagulation or antithrombotic agents, including heparin products, is not recommended in the newborn without identifiable risk factors; (6) the study group recommends that in case of delayed motor milestones or early handedness, multidisciplinary rehabilitation is recommended as early as possible. Newborns should have physical therapy evaluation and ongoing outpatient follow-up. Given the risk of later-onset cognitive, language, and behavioral disabilities, neuropsychological testing in preschool and at school age is highly recommended.
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Infarto Cerebral/terapia , Adhesión a Directriz , Infarto Cerebral/diagnóstico , Infarto Cerebral/etiología , Diagnóstico Diferencial , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Comunicación Interdisciplinaria , Colaboración Intersectorial , Recurrencia , Factores de RiesgoRESUMEN
PURPOSE: Thrombosis of cerebral arteriovenous malformation after embolization is rare, but can involve the normal venous network with extensive venous thrombosis. We report angioarchitecture findings, our management and prevention strategy for this complication in pediatric AVMs. METHODS: In this 5.5-year retrospective series, we reviewed records of 13 patients under 15 years who were anticoagulated after embolization. In our initial experience 4 children who didn't receive any prophylactic anticoagulation presented with extensive venous thrombosis after embolization (group 1). Following this, nine children with similar angioarchitecture and embolization modalities were treated with prophylactic anticoagulation immediately after embolization (group 2). We analyzed the type of AVM, angioarchitecture, dose of prophylactic anticoagulant, efficacy/complications of treatment and late outcome. RESULTS: All patients in group 1 had severe jugular bulb stenosis/occlusion associated with cerebral venous dilatation. In group 2 with similar angioarchitecture, only three patients (33%) developed extensive thrombosis. In both groups, thrombosis occurred within two days of treatment in six children and two weeks in one child. The diagnosis was suspected on intracranial hypertension in five patients and occulomotor disorder in one. One was asymptomatic. All children were treated with therapeutic doses of LMWH (anti-Xa: 0.5-1). No hemorrhagic complications occurred. Good venous remodeling was observed in all but one patient. CONCLUSION: Anticoagulation in extensive venous thrombosis after AVM embolization in children appears to be safe and effective. In cases with angioarchitectural features of dilatation of the cerebral venous network and occlusion/severe stenosis of the jugular bulbs, full dose anticoagulation may be required to prevent thrombosis.
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Embolización Terapéutica/efectos adversos , Malformaciones Arteriovenosas Intracraneales/terapia , Trombosis Intracraneal , Malformaciones de la Vena de Galeno , Trombosis de la Vena , Anticoagulantes/uso terapéutico , Angiografía Cerebral , Niño , Preescolar , Constricción Patológica/complicaciones , Femenino , Humanos , Lactante , Malformaciones Arteriovenosas Intracraneales/complicaciones , Trombosis Intracraneal/complicaciones , Trombosis Intracraneal/etiología , Trombosis Intracraneal/prevención & control , Angiografía por Resonancia Magnética , Masculino , Pediatría , Estudios Retrospectivos , Tomógrafos Computarizados por Rayos X , Malformaciones de la Vena de Galeno/complicaciones , Malformaciones de la Vena de Galeno/etiología , Malformaciones de la Vena de Galeno/prevención & control , Trombosis de la Vena/complicaciones , Trombosis de la Vena/etiología , Trombosis de la Vena/prevención & controlRESUMEN
The accurate morphological exploration of the brain is a major challenge in neonatology that advances in magnetic resonance imaging (MRI) can now provide. MRI is the gold standard if an hypoxic ischemic pathology is suspected in a full term neonate. In prematures, the specific role of MRI remains to be defined, secondary to US in any case. We present a state of the art of hardware and software technical developments in MRI. The increase in magnetic field strength (3 tesla) and the emergence of new MRI sequences provide access to new information. They both have positive and negative consequences on the daily clinical data acquisition use. The semiology of brain imaging in full term newborns and prematures is more extensive and complex and thereby more difficult to interpret. The segmentation of different brain structures in the newborn, even very premature, is now available. It is now possible to dissociate the cortex and basal ganglia from the cerebral white matter, to calculate the volume of anatomical structures, which improves the morphometric quantification and the understanding of the normal and abnormal brain development. MRI is a powerful tool to analyze the neonatal brain. The relevance of the diagnostic contribution requires an adaptation of the parameters of the sequences to acquire and of the image processing methods.
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Encéfalo/patología , Imagen por Resonancia Magnética/tendencias , Encéfalo/crecimiento & desarrollo , Encefalopatías/diagnóstico , Humanos , Recién Nacido , Recien Nacido Prematuro , Imagen por Resonancia Magnética/métodosRESUMEN
Controlled-rate freezing and storage in vapour phase nitrogen are used by most transplantation teams for the cryopreservation and storage of peripheral blood haematopoietic stem cells (PBSC). In this study, we analysed 666 autologous PBSC transplants after uncontrolled freezing and storage of PBSC at -80 °C. Statistical analysis showed that neutrophil recovery was associated with both the infused CD34(+) cell dose (P=0.01) and the post transplantation use of growth factors (P<0.001) and that platelet recovery was associated with the infused CD34(+) cell dose (P<0.001) and with the diagnosis (P=0.02). We analysed three groups according to the duration of the cryopreservation period (less than 6 months, between 6 and 12 months or more than 1 year). Haematopoietic recovery was not found to be adversely affected by longer storage at -80 °C. The haematopoietic recoveries of 50 pairs of sequential transplantations from the same PBSC mobilization were analysed. Despite prolonged cryopreservation, there were no statistically significant differences in neutrophil (P=0.09) or platelet (P=0.22) recovery in the second compared with the first transplant. In conclusion, the long-term storage of PBSC at -80 °C after uncontrolled-rate freezing is an easy and comparatively inexpensive cryopreservation method that leads to successful haematopoietic recovery even after prolonged storage.
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Conservación de la Sangre/métodos , Criopreservación/métodos , Células Madre Hematopoyéticas , Trasplante de Células Madre de Sangre Periférica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Autoinjertos , Bélgica , Niño , Preescolar , Femenino , Francia , Neoplasias Hematológicas/terapia , Hematopoyesis , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Adulto JovenRESUMEN
A new test of percolation under pressure is proposed to estimate the pollution potential of wastes in various scenarios. Depending on the use foreseen for the material, samples can be analysed in a granular or monolithic state. The proposed trial keeps the physical structure of the samples and accelerates the phenomena by applying a pressure variation in order to obtain many important data, such as permeability and the environmental release of species. In this paper, some results of this percolation test are presented for hydraulic-binder-treated gravels and sands that include polluted treated sediments. The results are repeatable and a steady flow is reached for each kind of sample. Incorporation of the waste leads to a drop in the permeability of road materials even though their characterization shows that they are more porous. The capacity to resist aggressive ion penetration can then be estimated. The release kinetics of heavy metals are studied and the environmental release results are compared with data from a regulatory leaching test. Differences can be observed and the percolation test seems to be more sensitive for most of the heavy metals measured.
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Materiales de Construcción/análisis , Ambiente , Monitoreo del Ambiente/métodos , Contaminación Ambiental/análisis , Contaminantes del Suelo/análisis , Residuos/análisis , AbsorciónRESUMEN
Three types of brain arteriovenous vascular malformations can be found during the neonatal period, according to their anatomical location. Vein of Galen malformations are the most common. The others are pial arteriovenous malformations or dural arteriovenous malformations, which include dural sinus malformations. They can be asymptomatic, but most often they are associated with different symptoms, related to their angioarchitecture or their effect on the brain. High-flow arteriovenous malformations can thus be responsible for heart failure. Local or regional venous hyperpressure exposes the patient to subacute or chronic brain lesions, or to hydrovenous disorders such as hydrocephalus. Some types of venous reflux can expose patients to brain hemorrhage. The treatment chosen for these vascular malformations and their consequences is transarterial or transvenous embolization, depending on the angioarchitecture and type of lesion. The schedule for the treatment will be determined according to the malformation type and its local or general effects on the brain. The aim of this article is to present the recommendations of the French National Referral Center for neurovascular malformations in children, in order to help clinicians and radiologists treat these patients during pre- or neonatal period.
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Insuficiencia Cardíaca/prevención & control , Malformaciones Arteriovenosas Intracraneales/diagnóstico , Malformaciones Arteriovenosas Intracraneales/terapia , Tamizaje Neonatal , Diagnóstico Prenatal , Venas Cerebrales/anomalías , Femenino , Francia , Humanos , Recién Nacido , Embarazo , Pronóstico , Sociedades MédicasRESUMEN
Non-accidental brain trauma (also called shaken baby syndrome) represent the main cause for morbidity and mortality in the context of child abuse. It often occur in young infants aged less than 8months. The shaking leading to brain injuries are very violent and sometimes associated with a final impact. Intracranial injuries may be isolated without skeletal trauma or bruising. In any suspicion of such a diagnosis, emergency hospitalization is indicated. Brain CT, easy to perform in emergency, is the diagnostic key. It discloses diffuse subdural hematomas in typical sites as vertex, interhemispheric space and tentorium. There is no clear background of trauma and the related story is changing over time. The 3D analysis of the skull looks for signs of recent impact as a fracture that is sometimes complex and/or a soft tissue swelling of the scalp. Intraparenchymal injuries (contusions, tearing, and overall anoxic ischemic injuries) are better analyzed with MRI. The prognosis depends on their extent. Ophtalmologic examination is systematically performed looking for retinal hemorrhages (around one third of cases) which may be very subtle. Bruising is a major diagnostic sign, but inconstantly present. A precise datation of skeletal and/or brain injuries is not possible with imaging and the only indication of use is to establish the presence of "age different lesions". This indicates repeated trauma and thereby a high risk of recurrence.
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Síndrome del Bebé Sacudido/diagnóstico , Humanos , Lactante , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos XRESUMEN
An experimental study of the oxidation of ethylcyclohexane has been performed in a jet-stirred reactor with online gas chromatography, under quasi-atmospheric pressure (800 Torr), at temperatures ranging from 500 to 1100 K (low- and intermediate-temperature zone including the negative temperature coefficient area), at a residence time of 2 s, and for three equivalence ratios (0.25, 1, and 2). Ethylcyclohexane displays important low-temperature reactivity with a well-marked negative temperature coefficient behavior. In addition to 47 products with a mass lower than ethylcyclohexane which have been quantified, many species with a C(8)H(14)O formula (molecular weight of 126) were detected by GC-MS and 7 of them were quantified. These molecules are cyclic ethers, ketones, and aldehydes with the same carbon skeleton as the reactant. Experiments were also carried on under the same conditions for two other C(8) hydrocarbons, n-octane and 1-octene, showing that the reactivity of ethylcyclohexane is close to that of the alkene and lower than that of the alkane. Simulations using a detailed kinetic model of the literature allow a good prediction of the global reactivity and of the main hydrocarbon products for temperatures above 800 K. The main reaction channels leading to the observed reaction products at both low (below 800 K) and intermediate temperature (above 800 K) are discussed.
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The objective of the work presented in this paper is the quantitative determination of the mineral composition of two complex mineral wastes: a sewage sludge ash (SSA) and a municipal solid waste incineration fly ash (MSWIFA). The mineral compositions were determined by two different methods: the first based on calculation using the qualitative mineralogical composition of the waste combined with physicochemical analyses; the second the Rietveld method, which uses only X-ray diffraction patterns. The results obtained are coherent, showing that it is possible to quantify the mineral compositions of complex mineral waste with such methods. The apparent simplicity of the Rietveld method (due principally to the availability of software packages implementing the method) facilitates its use. However, care should be taken since the crystal structure analysis based on powder diffraction data needs experience and a thorough understanding of crystallography. So the use of another, complementary, method such as the first one used in this study, may sometimes be needed to confirm the results.
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Carbono/química , Material Particulado/química , Aguas del Alcantarillado , Administración de Residuos/métodos , Algoritmos , Ceniza del Carbón , Cristalografía por Rayos X/métodos , Incineración , Análisis de los Mínimos Cuadrados , Microscopía Electrónica de Rastreo/métodos , Minerales/química , Modelos Teóricos , Polvos , Eliminación de Residuos/métodos , Programas Informáticos , Difracción de Rayos XRESUMEN
Tuberculous meningitis is uncommon in western countries and its outcome is poor when it is not diagnosed and treated in good time. Here, we present a case of febrile brain stroke revealing a tuberculous arachnoiditis in a 13-month-old infant living in a non-endemic country. Thanks to prompt specific antibiotherapy, the clinical outcome was globally favourable in spite of the occurrence of an asymptomatic brain tuberculoma, which disappeared spontaneously. Although tuberculous meningitis is rare in non-endemic countries, it must be evoked in strokes occurring in a febrile context.
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Antituberculosos/uso terapéutico , Isquemia Encefálica/complicaciones , Fiebre/complicaciones , Accidente Cerebrovascular/complicaciones , Tuberculosis Meníngea/diagnóstico , Tuberculosis Meníngea/tratamiento farmacológico , Isquemia Encefálica/diagnóstico , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Accidente Cerebrovascular/diagnóstico , Resultado del Tratamiento , Tuberculosis Meníngea/complicacionesRESUMEN
This paper summarizes the minimal workout of chronic lymphoproliferative disorders in a routine laboratory of haematology as recommended by a team of experienced laboratory supervisors in Belgium, taking into account the specific organisation of healthcare in Belgium, the innovations in the field of molecular analyses and related reimbursement. The starting point was essentially based upon clinical and/or haematological indications and it is emphasized that conclusions should be drawn in close dialogue with the clinician and experts in cytogenetics and histopathology. Reports made in the laboratory should be based upon an integration of cytomorphological, immunophenotypical and molecular data. These guidelines are not intended to be used as universal 'diagnostic pathways', but should be useful in developing local diagnostic pathways. It is well understood that this consensus, being valid anno 2009, may rapidly change with new technologies being introduced and new targets discovered.
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Pruebas Hematológicas/normas , Trastornos Linfoproliferativos/sangre , Bélgica , Enfermedad Crónica , Técnicas de Laboratorio Clínico/normas , HumanosRESUMEN
Pregabalin is similar in structure to gamma-aminobutyric acid. It is used for neuropathic pain, generalized anxiety disorders and as an adjunct therapy for partial seizures. Tachycardia is a rare side-effect. A 92-year-old patient with a history of paroxystic fibrillation was hospitalised for zoster. She developed a sinusal tachycardia followed by atrial fibrillation and congestive heart failure 15 h after a first dose of pregabalin. The imputation was considered as plausible. Even though the mechanism remains unclear, pregabalin might induce tachycardia in predisposed old patients.
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Analgésicos/efectos adversos , Fibrilación Atrial/inducido químicamente , Taquicardia Paroxística/inducido químicamente , Ácido gamma-Aminobutírico/análogos & derivados , Anciano de 80 o más Años , Aminas/uso terapéutico , Analgésicos/uso terapéutico , Ácidos Ciclohexanocarboxílicos/uso terapéutico , Femenino , Gabapentina , Insuficiencia Cardíaca/inducido químicamente , Herpes Zóster/tratamiento farmacológico , Humanos , Neuritis/tratamiento farmacológico , Pregabalina , Ácido gamma-Aminobutírico/efectos adversos , Ácido gamma-Aminobutírico/uso terapéuticoRESUMEN
This second of two articles dealing with the utilization of MSWI fly ash in blended cement studies the effects of two variants of the stabilization process on the behavior of the treated fly ash (TFA) introduced into cement-based mortars. From a technological point of view, the modifications of the process are very efficient and eliminate the swelling produced by the introduction of MSWI fly ash in cement-based mortars. TFA has a significant activity in cement-based mortars and can also advantageously replace a part of the cement in cement-based material. From an environmental point of view, the results of traditional leaching tests on monolithic and crushed mortars highlight a poor stabilization of some harmful elements such as antimony and chromium. The use of a cement rich in ground granulated blast furnace slag (GGBFS) with a view to stabilizing the chromium is not efficient. Since neither adequate tests nor quality criteria exist to evaluate the pollutant potential of a waste with a view to reusing it, it is difficult to conclude on the environmental soundness of such a practice. Further experiments are necessary to investigate the environmental impact of TFA introduced in cement-based mortars depending on the reuse scenario.
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Carbono/química , Materiales de Construcción , Incineración , Material Particulado/química , Ceniza del Carbón , Fuerza Compresiva , Ambiente , Contaminantes Ambientales/análisis , Metales/análisis , Reología , Dióxido de Silicio/química , Agua/químicaRESUMEN
This paper is the first of a series of two articles dealing with the processes applied to MSWI fly ash with a view to reusing it safely in cement-based materials. Part 1 presents two stabilization processes and Part 2 deals with the use of the two treated fly ashes (TFA) in mortars. Two types of binder were used: an Ordinary Portland Cement (OPC) containing more than 95% clinker (CEM I 52.5R) and a binary blend cement composed of 70% ground granulated blast furnace slag and 30% clinker (CEM III-B 42.5N). In this first part, two stabilization processes are presented: the conventional process, called "A", based on the washing, phosphation and calcination of the ash, and a modified process, called "B", intended to eliminate metallic aluminum and sulfate contained in the ash. The physical, chemical and mineralogical characteristics of the two TFA were comparable. The main differences observed were those expected, i.e. TFA-B was free of metallic aluminum and sulfate. The mineralogical characterization of the two TFAs highlighted the presence of large amounts of a calcium aluminosilicate phase taking two forms, a crystalline form (gehlenite) and an amorphous form. Hydration studies on pastes containing mixed TFA and calcium hydroxide showed that this phase reacted with calcium hydroxide to form calcium aluminate hydrates. This formation of hydrates was accompanied by a hardening of the pastes. These results are very encouraging for the reuse of such TFA in cement-based materials because they can be considered as pozzolanic additions and could advantageously replace a part of the cement in cement-based materials. Finally, leaching tests were carried out to evaluate the environmental impact of the two TFAs. The elements which were less efficiently stabilized by process A were zinc, cadmium and antimony but, when the results of the leaching tests were compared with the thresholds of the European landfill directive, TFA-A could nevertheless be accepted at landfills for non-hazardous waste. The modifications of the process led to a significant reduction in the stabilization of chromium, selenium and antimony.
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Carbono/química , Carbono/toxicidad , Materiales de Construcción/análisis , Incineración , Material Particulado/química , Material Particulado/toxicidad , Eliminación de Residuos/métodos , Aluminio/química , Carbonato de Calcio/química , Hidróxido de Calcio/química , Fenómenos Químicos , Química Física , Ceniza del Carbón , Francia , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Solubilidad , Sulfatos/química , Difracción de Rayos XRESUMEN
Neuroimaging and management advances require review of indications for excluding cerebral venous sinus (sinovenous) thrombosis (CSVT) in children. Our goals were to examine (i) clinical presentations of CSVT, (ii) prothrombotic risk factors and other predisposing events, (iii) clinical and radiological features of brain lesions in CSVT compared with arterial stroke, and (iv) predictors of outcome. We studied 42 children with CSVT from five European paediatric neurology stroke registries. Patients aged from 3 weeks to 13 (median 5.75) years (27 boys; 64%) presented with lethargy, anorexia, headache, vomiting, seizures, focal signs or coma and with CSVT on neuroimaging. Seventeen had prior chronic conditions; of the 25 previously well patients, 23 had recent infections, eight became dehydrated and six had both. Two children had a history compatible with prior CSVT. Anaemia and/or microcytosis (21 probable iron deficiency, five haemolytic, including two with sickle cell disease and one with beta-thalassaemia) was as common (62%) as prothrombotic disorder (13/21 screened). High factor VIII and homozygosity for the thermolabile methylene tetrahydrofolate reductase polymorphism were the commonest prothrombotic disorders. The superficial venous system was involved in 32 patients, the deep in six, and both in four. Data on the 13 children with bland infarction and the 12 with haemorrhage in the context of CSVT were compared with those from 88 children with ischaemic (AIS) and 24 with haemorrhagic (AHS) arterial stroke. In multiple logistic regression, iron deficiency, parietal infarction and lack of caudate involvement independently predicted CSVT rather than arterial disease. Five patients died, three acutely, one after recurrence and one after 6 months being quadriparetic and blind. Follow-up ranged from 0.5 to 10 (median 1) years. Twenty-six patients (62%) had sequelae: pseudotumour cerebri in 12 and cognitive and/or behavioural disabilities in 14, associated with epilepsy in three, hemiparesis in two and visual problems in two. Eighteen patients, including six with haemorrhage, were anticoagulated. Older age [odds ratio (OR) 1.54, 95% confidence limits (CI) 1.12, 2.13, P = 0.008], lack of parenchymal abnormality (OR 0.17, 95% CI 0.02, 1.56, P = 0.1), anticoagulation (OR 24.2, 95% CI 1.96, 299) and lateral and/or sigmoid sinus involvement (OR 16.2, 95% CI 1.62, 161, P = 0.02) were independent predictors of good cognitive outcome, although the last predicted pseudotumour cerebri. Death was associated with coma at presentation. Of 19 patients with follow-up magnetic resonance (MR) venography, three had persistent occlusion, associated with anaemia and longer prodrome. A low threshold for CT or MR venography in children with acute neurological symptoms is essential. Nutritional deficiencies may be modifiable risk factors. A paediatric anticoagulation trial may be required, after the natural history has been further established from registries of cases with and without treatment.
Asunto(s)
Trombosis de los Senos Intracraneales/diagnóstico , Trombosis de los Senos Intracraneales/etiología , Adolescente , Anticoagulantes/uso terapéutico , Niño , Preescolar , Enfermedad Crónica , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Recién Nacido , Hipertensión Intracraneal/terapia , Imagen por Resonancia Magnética , Masculino , Pronóstico , Recurrencia , Sistema de Registros , Factores de Riesgo , Trombosis de los Senos Intracraneales/tratamiento farmacológico , Accidente Cerebrovascular/diagnóstico , Trombofilia/etiología , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
The notion of emergency with regards to pediatric neuroimaging requires a strong knowledge of clinical indications. In children under 2 years of age, head trauma requires a CT scan in case of repeated or prolonged or rapidly increasing vomiting, focal signs, loss of consciousness, unusual behavior, seizures, clinical signs of skull fracture or polytrauma. The "shaken baby syndrome" is usually suspected in case of loss of consciousness or seizures before 8 months of age. The hematomas that are observed are subdural in location, diffuse and deeply located. Imaging is only mandatory for headache suggesting underlying space occupying lesion: permanent or increasing pain, nocturnal headache, headache during postural changes or efforts, associated to seizures or abnormal neurological examination. No imaging is indicated in case of first epileptic seizure associated to normal neurological examination and without any particular context. The presence of trauma, intracranial hypertension, persisting disturbances of consciousness or associated focal sign necessitates urgent neuroimaging. No imaging is indicated in case of typical febrile seizures, i.e. generalized, brief and occurring between 1 and 5 years of age. Spinal cord symptoms require immediate MRI evaluation. The most frequent tumor is neuroblastoma. In the absence of spinal tumor, brain abnormalities must be excluded (inflammatory disease). In neonates, CT scan or MRI must be readily performed in case of seizures or loss of consciousness to exclude ischemic, traumatic or infectious lesions.