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The clinical manifestations of central nervous system (CNS) vasculitis are highly variable. In the absence of a positive CNS biopsy, CNS vasculitis is particularly suspected when markers of both vascular disease and inflammation are present. To facilitate the clinical and therapeutic approach to this rare condition, CNS vasculitis can be classified according to the size of the involved vessels. Vascular imaging is used to identify medium vessel disease. Small vessel disease can only be diagnosed with a CNS biopsy. Medium vessel vasculitis usually presents with focal neurological signs, while small vessel vasculitis more often leads to cognitive deficits, altered level of consciousness and seizures. Markers of CNS inflammation include cerebrospinal fluid pleocytosis or elevated protein levels, and vessel wall, parenchymal or leptomeningeal enhancement. The broad range of differential diagnoses of CNS vasculitis can be narrowed based on the disease subtype. Common mimickers of medium vessel vasculitis include intracranial atherosclerosis and reversible cerebral vasoconstriction syndrome. The diagnostic workup aims to answer two questions: is the neurological presentation secondary to a vasculitic process, and if so, is the vasculitis primary (i.e., primary angiitis of the CNS) or secondary (e.g., to a systemic vasculitis, connective tissue disorder, infection, malignancy or drug use)? In primary angiitis of the CNS, glucocorticoids and cyclophosphamide are most often used for induction therapy, but rituximab may be an alternative. Based on the available evidence, all patients should receive maintenance immunosuppression. A multidisciplinary approach is necessary to ensure an accurate and timely diagnosis and to improve outcomes for patients with this potentially devastating condition.

This paper proposes a comparative study of two techniques of granulation of a submicronic alumina powder with high binder content slurries, by spray drying and freeze granulation for the preparation of mixed granules. First, the viscosity and flow index of the suspensions are given as a function of dispersant, solid and binder contents versus alumina content, and the data are analysed in order to give a predictive model in a wide range. Suspensions with varying viscosities (7–208 mPa.s), densities (1.31–1.76) and surface tensions (23–40 mN/m) were then granulated. The first observations reveal the importance of the content and the molar mass of the binder: when they are too high, the freeze granulation fails and filaments are produced instead of granules due to extensive stretching of the molecular chains of the binder during spraying. Then through a theoretical analysis of the phenomena leading to granulation, an original dimensionless number is proposed to describe the evolution of the granule size as a function of suspension formulation. This number is related to the Reynolds and Weber number and is able to predict the granule size over a wide range (20–500 μm for freeze granulation, and 5–30 μm for spray drying). Spray drying leads to smaller granules with various shapes, from full shape to hollow or donut-like, whereas freeze granulation leads to bigger but spherical granules with a microporosity, and a size easier to predict as no drying shrinkage is observed.

Resumen Las vasculitis necrosantes sistemicas primarias son afecciones infrecuentes, pero potencialmente graves, cuyas causas se desconocen en la mayoria de los casos y cuyos mecanismos fisiologicos y patogenos solo se comprenden parcialmente. Las principales son: poliarteritis nudosa (PAN), polivasculitis microscopica (PVM), granulomatosis con polivasculitis (GPV) (anteriormente denominada enfermedad de Wegener), granulomatosis eosinofilica con polivasculitis (GEPV) (anteriormente denominado sindrome de Churg-Strauss), enfermedad de Kawasaki, algunas vasculitis cutaneas leucocitoclasticas, vasculitis por inmunoglobulinas A (IgA) (anteriormente denominada purpura reumatoidea o de Schoenlein-Henoch) y vasculitis crioglobulinemicas. Se definen por la inflamacion y la necrosis de las paredes vasculares, principalmente de las arterias, pero a veces de los capilares y las venulas. Se clasifican segun el calibre de los vasos afectados y otras caracteristicas histologicas y clinicas: presencia o ausencia de granulomas, infiltrados eosinofilicos o depositos de Ig, pero tambien criterios clinicos e inmunologicos, en particular la deteccion (o no) de autoanticuerpos sericos dirigidos contra el citoplasma de los neutrofilos (ANCA). En Francia, por ejemplo, su prevalencia varia de 11 por millon de habitantes para la GEPV a 31 por millon de habitantes para la PAN. Todos los organos pueden verse afectados, pero la mayoria de las veces estas vasculitis tienen expresiones clinicas muy distintas entre si. Los pacientes con PAN, por ejemplo, a menudo tienen alteracion del estado general con fiebre, dolor abdominal, mononeuritis multiple (o multineuritis) e hipertension arterial o incluso insuficiencia renal de tipo renovascular. La GPV (Wegener) tiene un tropismo especial por las estructuras otorrinolaringologicas (sinusitis, rinitis costrosa, otitis), los pulmones (nodulos cavitados o no, a veces hemorragia alveolar) y los rinones (glomerulonefritis extracapilar). La GEPV (sindrome de Churg-Strauss) se revela con frecuencia por asma de aparicion tardia, resistente, con eosinofilia y posiblemente mononeuritis multiple, manifestaciones cutaneas (purpura, urticaria, exantema maculoso) y sistemicas. Deben buscarse causas infecciosas, en particular una infeccion por el virus de la hepatitis B para la PAN o de la hepatitis C para las vasculitis crioglobulinemicas, cuyo tratamiento incluye antivirales, que han demostrado ser eficaces en estos casos. El tratamiento de la GPV, de la PVM y de las demas vasculitis ajenas a las infecciones esta ahora bastante bien codificado, con asociaciones de corticoides y de inmunosupresores, cuya intensidad puede adaptarse a la gravedad de la enfermedad y a las caracteristicas generales del paciente. Algunos anticuerpos monoclonales han demostrado ser eficaces para el tratamiento de las vasculitis asociadas con los anticuerpos anticitoplasma de neutrofilos (ANCA). El pronostico ha mejorado de forma considerable en los ultimos 30 anos, con una supervivencia de alrededor del 80% a 10 anos. Aunque las causas y los mecanismos patogenos de estas vasculitis aun no han sido aclarados, los progresos terapeuticos son constantes.

Both monolithic and multilayer mullite-alumina ceramic composites dedicated to ballistic applications were produced by uni-axial pressing and tape casting before being sintered at 1510 °C. The compositions combining andalusite and kaolin in addition to α-alumina exhibit the more promising mechanical properties, reaching the performances of pure ballistic alumina. However, for a given bulk density value, a significant improvement of the performances (Young's modulus and ballistic impedance) only by varying the composition of the monoliths is limited. The second approach reported in this work has consisted in the development of judicious multilayer materials based on the generation of internal residual stresses in thinner layers. Compared to the monolithic materials, the most efficient multilayer configurations exhibit a failure stress improved by +35% and a fracture energy increased by +60%. Indeed, the layers subjected to compressive stress promote a significant crack bifurcation during rupture.

Introduction Vascular Behcet's (VB) is a rare inflammatory disorder with venous and less commonly arterial involvement. Coronary arteries are rarely involved. High clinical suspicion is required to make the diagnosis when the mucocutaneous manifestations of Behcet's are absent. Case Report A 45-year-old Portuguese male with prior unprovoked venous thromboembolism at the age of 30 presented with ST-elevation myocardial infarction and cardiogenic shock. Coronary angiography showed a large left main (LM) aneurysm with thrombus (Figure 1A). He underwent LM balloon angioplasty and coronary artery bypass grafting. Postoperatively, he was placed on peripheral venoarterial-extracorporeal membrane oxygenation for cardiogenic shock with biventricular failure, as a bridge to decision. An intraoperative right ventricular biopsy showed only fibrinous pericarditis. He required septostomy for left ventricular decompression. Despite therapeutic heparinization, he was diagnosed with bilateral pulmonary emboli and occlusion of the common hepatic artery proper with suspected porta hepatis arterial aneurysm (Figure 1B-C). He was found to carry the HLA-B51 allele and thus VB was favoured as a unifying diagnosis. Intravenous solumedrol was administered, but the patient developed anuric renal failure and limb ischemia. He ultimately succumbed to his illness due to septic shock with multiorgan failure. An autopsy confirmed the coronary aneurysm (Figure 1D) but could not confirm etiology. The hepatic aneurysm was not confirmed on autopsy due to technical challenges. Summary VB can lead to cardiac complications such as coronary aneurysms or thrombosis which may be the initial presentation in a smaller proportion of patients. Though immunosuppression is the mainstay of treatment, there is no established protocol and mortality/morbidity remain high. VB should be included in the differential diagnosis of a young patient presenting with coronary aneurysms to prompt appropriate therapy, though prognosis remains reserved.

The encapsulation of B4C and SiC carbide particles within a thin silica layer has been achieved via a processing route based on the sol–gel method. B4C powder must be previously calcined to improve the adhesion of the silica layer. The surface modification of the carbide particles has been characterized by microscopy analysis and zeta potential measurements. Natural sintering of the dense oxycarbide layers on an alumina-based substrate indicates that the covered carbide particles allow for control of the oxidation kinetics based on the coating thickness as well as the chemical nature and size of the carbide particles. The layer formulated with B4C and SiC particles exhibits high cohesion between the carbide grains and the substrate after sintering under an oxidizing atmosphere. The key processing parameters are discussed in this paper.

Colloidal granulation of alumina is an original shaping process leading to spherical granules directly in suspension from a diluted system. It is based on a heterocoagulation mechanism where silica added in small amount acts as a binding agent. The role of a submicronic latex of polystyrene was investigated, free, or as a hybrid object covered by silica nanoparticles synthesized by a Pickering emulsion polymerization method. Latex particles were not able to form primary agglomerates despite a high negative zeta potential. An addition of latex in combination with silica improved the state and homogeneity of the final microstructure which could be attributed to a decrease of the internal strains during the processing. Hybrid nanoparticles, by combining the binding agent (silica) and the organic phase, were able to form primary agglomerates, and to finally obtain alumina spheres exhibiting both a spherical morphology and a greater homogeneous microstructure.

Colloidal processing has long been used in ceramics to achieve green bodies with high densities, complex shapes and homogeneous microstructures, but they are rarely used to shape metal powders because of their high density and high surface reactivity. However, the possibility of processing fine particles makes these techniques interesting for metals, such as titanium, with a low density and high melting point. This work presents encouraging results in the design of aqueous suspensions of Ti particles to be shaped into bulk pieces by pressure slip casting (PSC), which opens new paths for the processing of fine and complex microstructures. Ti powders, measuring 10 μm in size, and mixtures of Ti and Al₂O₃ powders (added up to 5 wt.%) were dispersed in water by the addition of different stabilisers. The influence of the stabilisers in the slurry behaviour (in terms of nature, stereochemistry and active functional groups) was determined, as well as the incorporation of ceramic particles. A polyacrylic-based dispersant was selected as the best stabiliser to incorporate a second component (Al₂O₃) into the Ti suspension, whereas shear-thinning additives, such as TIRON, are preferred for PSC shaping. Suspensions with 1 wt.% Al₂O₃ were selected for processing composites by PSC and sintering. Sintered materials were characterised by measuring the density, oxygen content, hardness and microstructure analysis by SEM. Ti bulk pieces with 97% density and fine and homogeneous microstructure, of which the relationship between the oxygen content and hardness agrees with that measured for CPTi grade 4 (249 ± 24 HV30), can be processed by PSC. The authors would like to acknowledge the financial support from the Spanish Government through the projects MAT 2009-14448-C02-01 and 02, MAT2012 38650-C02-01 and 02 and to the regional government of Madrid through the programme Estrumat (Ref. S2009/MAT-1585).

This work describes the development of electrophoretic deposition method for the elaboration of a porous coating on a dense membrane in order to improve its oxygen permeation performance. The dense membrane material produced from La0.5Sr0.5Fe0.7Ga0.3O3-δ perovskite is coated with La0.6Sr0.4Fe0.8Co0.2O3-δ perovskite layer by electrophoretic deposition method in order to improve the kinetics of oxygen surface exchanges. Then, the oxygen flux through the La0.5Sr0.5Fe0.7Ga0.3O3-δ dense membrane is largely impacted by La0.6Sr0.4Fe0.8Co0.2O3-δ electrophoretic coating, from 0.5 to 2.6 10−3 mol⋅m−2⋅s−1 without and with La0.6Sr0.4Fe0.8Co0.2O3-δ coating after heating at 900 °C, respectively. Besides, a large impact of the thickness of the electrophoretic coating on the oxygen flux through the membranes is observed. The electrophoretic deposition has shown to be a powerful elaboration method of membrane to produce gaseous oxygen with high purity. Keywords: Electrophoretic coating, Oxygen semi-permeation, Porous layer, Mixed conductor

Besides hepatic manifestations of hepatitis B virus (HBV) infection, some extrahepatic systemic and/or autoimmune manifestations may occur with both acute and chronic viral infections, usually independent of hepatic involvement. The most common one is the prodromal preicteric flu-like syndrome with arthralgias and sometimes urticarial cutaneous rash, observed in some patients with acute infection. Other extrahepatic manifestations include HBV-related glomerulonephritis or HBV-associated vasculitis (mainly polyarteritis nodosa type).

Les vascularites systemiques peuvent etre primitives, classees selon le calibre des vaisseaux atteints, ou secondaires, consequence d’une infection, d’une prise medicamenteuse, d’un cancer ou d’une autre maladie systemique comme la polyarthrite rhumatoide. Des manifestations digestives peuvent survenir, a des frequences variables, au cours de ces vascularites et revelent la maladie chez environ 15 % des patients. Les douleurs abdominales, les nausees, les vomissements ou les diarrhees sont frequents, mais peu specifiques. Une inflammation, un infiltrat purpurique et/ou necrotique et des ulcerations (parfois d’allure granulomateuse) des muqueuses sont possibles. Les atteintes ischemiques, les infarctus et les perforations intestinales, surtout de l’intestin grele, sont plus graves, de meme que les atteintes pancreatiques et les hemorragies digestives (notamment par rupture de microanevrismes). La prise en charge combinee medicale, et chirurgicale si necessaire, doit etre precoce. La survie a dix ans des patients atteints de vascularite systemique necrosante primitive est, aujourd’hui, de l’ordre de 80 %, en l’absence d’atteinte digestive ou si les manifestations digestives sont mineures. Le taux de survie a cinq ans n’est, par contre, que de 56 % en cas de manifestation digestive grave, chirurgicale.

Las vasculitis necrosantes sistemicas primarias son afecciones infrecuentes, pero potencialmente mortales. A pesar de que sus mecanismos fisiopatogenicos cada vez se comprenden mejor, sus causas se desconocen. Se caracterizan por la inflamacion y la necrosis de las paredes vasculares. Se clasifican segun el calibre de los vasos afectados y otras caracteristicas histologicas, como la presencia o la ausencia de granulomas, infiltrados eosinofilos o depositos de inmunoglobulinas, pero tambien segun criterios clinicos y analiticos, en especial la deteccion de autoanticuerpos sericos dirigidos contra el citoplasma de los neutrofilos (ANCA). En Francia, por ejemplo, su prevalencia varia desde 11/1.000.000 de habitantes para el sindrome de Churg-Strauss, hasta 31/1.000.000 para la poliarteritis nudosa. Aunque todos los organos pueden estar afectados, la mayoria de las veces se presentan mediante cuadros clinicos bastante diferentes. Asi, los afectados por una poliarteritis nudosa presentan a menudo una alteracion del estado general con fiebre, dolores abdominales, polineuritis e hipertension arterial, e incluso una insuficiencia renal de causa vascular. La granulomatosis de Wegener tiene un tropismo especial por las estructuras otorrinolaringeas (sinusitis, rinitis costrosa), los pulmones (nodulos cavitados o no) y los rinones (glomerulonefritis extracapilar). El sindrome de Churg-Strauss se revela con frecuencia por un asma resistente con eosinofilia y, en ocasiones, por polineuritis y manifestaciones cutaneas y generales. Deben buscarse causas infecciosas, sobre todo una infeccion por el virus de la hepatitis B para la poliarteritis nudosa, o de la hepatitis C para las vasculitis crioglobulinemicas, cuyo tratamiento se basa en primer lugar en los antivirales. La eficacia de estos ultimos se ha demostrado en tales casos. El tratamiento de la granulomatosis de Wegener, de la poliangitis microscopica y de las demas vasculitis ajenas a las infecciones virales esta bien codificado. Consiste en asociaciones de corticoides e inmunosupresores a dosis que se ajustan a la gravedad de la enfermedad y a las caracteristicas del paciente. El pronostico ha mejorado de forma considerable en los ultimos 30 anos, con una supervivencia de alrededor del 80% en 10 anos. Sin embargo, aun hay que aclarar muchos aspectos en lo que se refiere a la fisiopatogenia y al tratamiento.

Resume Les vascularites systemiques constituent un groupe heterogene de maladies au cours desquelles des manifestations graves peuvent survenir, inaugurales ou plus tardives, en rapport avec une poussee de la maladie ou un effet indesirable des traitements. Les atteintes cardiaques representent la premiere cause de mortalite au cours de la maladie de Kawasaki et du syndrome de Churg et Strauss, et les atteintes digestives severes (peritonite, perforations surtout) au cours de la periarterite noueuse. Les atteintes neurologiques centrales, principalement a type d'encephalopathie diffuse ou multifocale ou d'accidents vasculaires, sont rares mais de mauvais pronostic. La glomerulonephrite necrosante segmentaire et focale, associee a une proliferation extracapillaire, est l'atteinte renale la plus typique et represente l'une des premieres causes d'admission en reanimation de ces patients. Les hemorragies intra-alveolaires sont la manifestation pulmonaire la plus caracteristique au cours de la polyangeite microscopique et de la granulomatose de Wegener. D'autres manifestations peuvent conduire les patients en soins intensifs, liees a la vascularite (stenoses sous-glottiques ou endobronchiques, HTA maligne, embolie pulmonaire…), ou aux traitements immunosuppresseurs, en particulier les infections et les reactions immunoallergiques (notamment pulmonaires). Les choix therapeutiques reposent sur des criteres valides, tel le five factor score , et doivent etre pris de facon collegiale, afin de ne pas retarder, par crainte des effets secondaires, un traitement immunosuppresseur indispensable, ou a l'inverse de ne pas meconnaitre une autre cause a la decompensation, notamment infectieuse.

Resume Introduction. – L’histiocytose langerhansienne est une maladie rare, qui touche surtout le jeune enfant. L’atteinte hepatique represente un facteur de mauvais pronostic. Une cholangite sclerosante peut survenir chez 10 a 15 % des patients atteints de forme multiviscerale. Nous rapportons le cas d’un homme de 56 ans qui a developpe une cholangite sclerosante 12 ans apres le diagnostic d’histiocytose langerhansienne. Exegese. – Un homme de 56 ans est hospitalise pour alteration de l’etat general associee a des epigastralgies. Il est suivi pour une histiocytose langerhansienne revelee 12 ans auparavant par un diabete insipide, puis compliquee d’une atteinte fibrokystique pulmonaire et osteocondensante vertebrale. La maladie est cependant quiescente depuis 1 an. Il ne prend aucun traitement. Il existe une cholestase et un syndrome inflammatoire biologique. Les explorations radiologiques digestives (scanner, bili-IRM et echoendoscopie) revelent une hepatomegalie et un epaississement parietal regulier et diffus de l’arbre biliaire intra- et extrahepatique. La ponction–biopsie du foie confirme le diagnostic de cholangite sclerosante. Une corticotherapie orale est debutee, permettant une amelioration clinique et biologique (12 mois de recul). Conclusion. – La cholangite sclerosante est une complication classique de l’histiocytose langerhansienne, principalement en cas de forme multiviscerale. Elle survient en moyenne 2 ans apres le diagnostic chez l’enfant, mais parfois bien plus tard, notamment chez l’adulte, alors que l’histiocytose langerhansienne semble ne plus evoluer. Le diagnostic repose sur les explorations radiologiques et l’histologie hepatique. Habituellement, cette forme de cholangite sclerosante repond mal au traitement de l’histiocytose langerhansienne et la transplantation hepatique doit souvent etre envisagee.

Emphysematous pyelonephritis is a rare, life-threatening complication of upper urinary tract infections, characterized by the presence of gas in renal parenchyma and perirenal space. It occurs in 90% of cases in diabetic patients and E coli is the most common causative germ. The pathogenesis probably involves several factors including enhanced proliferation of microorganisms due to altered immune defences, mixed acid fermentation of glucose leading to gas production, and decreased elimination of the gas because of impaired tissue perfusion. Diagnosis is often delayed because the symptoms may be non-specific, as illustrated by the two cases we report herein. In patients with diabetes and febrile urinary tract infection, obstruction of the urinary tract should first be eliminated by echography. Then, if the infection does not rapidly respond to antimicrobial therapy, a scan should be performed. Aggressive management including correction of hemodynamics, parenteral antimicrobial therapy, and diabetes control with insulin therapy is mandatory, but a surgical procedure (nephrectomy or drainage) is almost always required.

The solid solution Cs4Sb4O8(Si4(1-x)Ge4xO12) has been studied using electron and X-ray diffraction, and 29Si MAS NMR. All compositions for 0 ≤ x ≤ 1 were found to be single phase. However, the mmm symmetry of the X4O12 rings is maintained for x ≤ 0.15. Structure determinations from single crystals corresponding to x = 0.5 and 0.6 indicate a random distribution of Si (and Ge) atoms on the tetrahedral X sites. Analysis of the 29Si MAS NMR spectra shows that the statistical distribution of Si (and Ge) atoms in the X4O12 rings is equally present at a local level.

The solid solution K 2x Ba 2−x Sb 4 O 9 (PO 4 ) 2 (0 < x < 0.4) has been prepared, and the structures of the end members K 0.8 Ba 1.6 Sb 4 O 9 (PO 4 ) 2 and Ba 2 Sb 4 O 9 (PO 4 ) 2 have been determined from single-crystal and powder diffraction data, respectively. The compounds crystallize in space group Pnma of the orthorhombic system with Z = 4 in cells of dimensions a = 20.998(3), b = 7.168(1), and c = 9.569(2) A for K 0.8 Ba 1.6 Sb 4 O 9 (PO 4 ) 2 and a = 20.9237(6), b = 7.1836(2), and c = 9.5189(3) A for Ba 2 Sb 4 O 9 (PO 4 ) 2 . Their structure consists of a three-dimensional arrangement of corner-sharing SbO 6 octahedra and PO 4 tetrahedra. In K 0.8 Ba 1.6 Sb 4 O 9 (PO 4 ) 2 , the K and Ba atoms are partially ordered among four possible sites, while in Ba 2 Sb 4 O 9 (PO 4 ) 2 , the Ba atoms occupy only two of these sites. Arguments for the distribution of the K and Ba atoms in K 0.8 Ba 1.6 Sb 4 O 9 (PO 4 ) 2 are presented

Central nervous system (CNS) vasculitides are a heterogeneous group of diseases that can lead to severe disability and death. Given the poor performance of available diagnostic procedures (magnetic resonance imaging, angiography and brain biopsy), the diagnosis of isolated CNS vasculitis is challenging. Differential diagnosis includes secondary CNS vasculitides (infection, cancer, drug exposure or systemic inflammatory disorders) and several non-inflammatory cerebral vasculopathies, such as the reversible cerebral vasoconstriction syndrome. Despite recent advances in neuroradiology and the publication of large retrospective case series, primary angiitis of the CNS remains a heterogeneous and challenging nosological entity. Prospective interdisciplinary studies are necessary to improve our approach to these patients.

Two alkali antimony silicates, K 4 Sb 4 O 8 (Si 4 O 12 ) and Cs 3 Sb 3 O 6 (Si 2 O 7 ) with strongly covalent and rather open octa hedraltetrahedral frameworks have been ion exchanged in acidic medium. Their proton exchanged derivatives are hydrated and their water content has been studied at 20°C as a function of relative humidity. Both compounds are true lattice hydrates and their thermal behavior, studied with use of TGA and X-ray diffraction, indicates that their dehydration process is reversible up to about 400°C. Titrations with different alkali hydroxide solutions show that they behave as solid acids with ion exchange properties.

A series of A 4 Sb 4 O 8 ( X 4 O 12 ) compounds ( A =K, Rb, Cs, Tl; X =Si, Ge) have been prepared either by solid-state reaction or via a sol-gel route. Single crystals of the cesium compounds have been isolated and their structure determined by X-ray diffraction. Cs 4 Sb 4 O 8 (Si 4 O 12 ) crystallizes in the tetragonal system, space group P 4 2 / mmc with a = 7.172(1)A, c = 19.645(2)A, Z = 2. The structure was determined from 557 reflections collected on a Nonius CAD4 diffractometer using the Mo Kα radiation. The final R index and weighted R w index are 0.026 and 0.024, respectively. The structure is built up from planes of cross-linked chains of corner-sharing SbO 6 octahedra, linked together via corner-sharing by four-membered Si 4 O 12 single rings. This three-dimensional arrangement delimits intercrossing tunnels wherein Cs cations are situated. Cs 4 Sb 4 O 8 (Ge 4 O 12 ) crystallizes in the tetragonal system, space group I 4 1 22 with a = 10.241(1) A, c = 40.073(6)A, Z = 8. Its structure was determined from 1303 reflections and refined to R = 0.034 and R w = 0.035. It appears as a slightly distorted form of the silicate analogue.

A KTP family compound, CsSbO(SiO3)2, have been prepared by mechanochemical mixing (MM) route or via a sol-gel route. They crystallize in the orthorhombic system, space group Pna21, Z=8 at 1100 °C. For both routes, preparation conditions have been optimized by s tudying the influence of various parameters such as calcination temperature, sintering temperature. The grain growth of sintered bodies is small with subsequent production of high dence pellets.

Primary angiitis of the central nervous system (PACNS) was first identified half a century ago, but it remains a rare and challenging disease. However, important advances have been made in the field of PACNS, mainly through recently published retrospective analyses of large groups of PACNS patients, and the consideration of reversible cerebral vasoconstriction syndrome as a distinct entity. Clinical manifestations of PACNS are variable and non-specific. Even though neuroimaging can be suggestive of vasculitis, only a leptomeningeal biopsy can definitively confirm vasculitis. However, a brain sample is taken in less than half the patients and cannot further help to distinguish between PACNS and secondary vasculitis of the central nervous system. Hence, physicians should be aware of all alternative diagnoses and PACNS mimickers, which are now well-known. Whereas prognosis now appears to be much better than for the first reported cases, probably attributable to the use of corticosteroids and immunosuppressants, mainly cyclophosphamide, the optimal therapeutic regimen, potentially based on each patient's characteristics, and its duration remain to be determined. Only multicenter studies and prospective therapeutic trials will be able to clarify these issues on therapy and eventually provide some data on PACNS physiopathogenesis, which remains a poorly explored domain.

To examine the diagnostic contributions of cardiac magnetic resonance imaging (CMRI) with delayed-enhancement (DE) in patients with Churg-Strauss syndrome (CSS).We consecutively recruited 14 men and 6 women (mean age: 50+/-14 years) with CSS (mean disease duration: 4.5+/-3.6 years) and investigated them independently of the presence/absence of cardiac manifestations. Cardiac manifestations included heart failure in 6 patients, angina pectoris in 1, isolated ECG abnormality in 1, and isolated echocardiography and ECG abnormalities in 1. T1-weighted sequences were recorded after gadolinium injection to study myocardial DE.CMRI abnormalities were found in 13/20 patients, including all 9 patients with myocardial manifestations, and 4 of the 11 asymptomatic patients. DE was centromyocardial in 6 patients, subepicardial in 4, and subendocardial in 3. Most enhanced lesions were in the anteroseptal or lateral walls. Patients with myocardial symptoms and DE had higher transmyocardial wall DE scores (mean: 9.4 vs. 3.7, respectively; p=0.01) and lower left ventricular ejection fractions (mean: 42% vs. 59%; p=0.001) than asymptomatic patients with DE.CMRI with DE enabled the detection of myocardial involvement in CSS patients with or without clinical symptoms. The clinical relevance of CMRI abnormalities in patients without clinical, echocardiographic and ECG signs of cardiac involvement remains unknown and needs to be evaluated in future studies. It seems premature to intensify treatment or to prescribe systematically steroids and cytotoxic agents based on the presence of isolated CMRI anomalies.

Preparation of dense pellets of solid solution compositions K(Ti 1−x Sb x )O(P 1−x Si x )O 4 has been studied. Two main routes have been investigated: mechanochemical mixing and sol-gel. For both methods, preparation conditions have been optimized by studying the influence of various parameters such as: heating rate, calcination temperature, cooling rate and sintering treatment. This study shows mainly that the calcination temperature must be choosen at the onset of the crystallization process and that a sintering treatment at 1323 K for 15 hr leads to the best results.

The single phase compound Na{sub 3}SbO(PO{sub 4}){sub 2} was prepared by a solid state reaction. It crystallizes in the orthorhombic system, space group P2{sub 1}2{sub 1}2{sub 1} with a = 6.964(1) {angstrom}, b = 9.284(2) {angstrom}, c = 12.425(2) {angstrom}, Z = 4. The structure was determined from 968 reflections collected on a Nonius CAD4 automatic diffractometer with MoK{alpha} radiation. The final R index and weighted R{sub w} index are 0.031 and 0.039, respectively. The structure is built up from strings of corner-sharing SbO{sub 6} octahedra to which phosphate groups are linked by two of their vertices. These chains, running parallel to the a-axis, are separated from each other by sodium atoms.

Many viruses can be responsible for systemic vasculitis, the most frequent being hepatitis B virus-related polyarteritis nodosa (HBV-PAN), even though its incidence has decreased over the past few decades. Mixed cryoglobulinemia has been shown to be associated with hepatitis C virus (HCV) infection in more than 80% of the patients, but it remains asymptomatic in most of them with only a minority developing vasculitis. Human immunodeficiency virus (HIV), erythrovirus B19, cytomegalovirus, varicella-zoster virus and human T-cell lymphotropic virus (HTLV)-1 have also been reported to be associated with or implicated in the development of vasculitides. On the other hand, some bacteria, fungi or parasites can also cause vasculitis, mainly by direct invasion of blood vessels or septic embolization, leading, e.g., to the well-known feature of 'mycotic aneurysm'. Syphilitic aortitis and/or cerebrovascular disease and rickettsial diseases are other, more specific, bacteria-induced vasculitides. Recognizing an infectious origin of vasculitides is of great importance because treatment strategies differ from those applied to non-infectious forms. Effective antimicrobial drugs are mandatory to treat bacterial, parasitic or fungal infections, while the combination of antiviral agents and plasma exchanges has been proven to be effective against HBV-PAN. This latter strategy might also be effective against HIV-associated vasculitis and, unlike cytotoxic agents, does not jeopardize the outcome of HIV-infected patients. In the context of HCV-related cryoglobulinemic vasculitis, antiviral drugs are necessary to achieve recovery, in combination with low-dose corticosteroids and/or rituximab. In the near future, newer antiviral agents will probably also have their place in the therapeutic armamentarium for these patients.

Plasma exchange can remove putative pathogenic autoantibodies and circulating immune complexes from the blood of patients with systemic lupus erythematosus (SLE). However, their efficacy has only been supported by noncontrolled and/or retrospective studies. Nonetheless, PE may still be of relevance in some selected SLE patients and as adjunctive therapy, in combination with corticosteroids (CS) and other immunosuppressant(s). We review herein the principal historical steps of the use of plasma exchange to treat SLE, based upon the main trials and case reports that have highlighted its most pertinent indications. Acute life-threatening manifestations and severe therapy-resistant manifestations, like refractory SLE renal disease, diffuse alveolar hemorrhage, neuropsychiatric SLE, thrombotic thrombocytopenic purpura, catastrophic antiphospholipid syndrome, hyperviscosity syndrome and cryoglobulinemia, are the indications for which plasma exchange might have a beneficial therapeutic role. Although few SLE patients undergo plasma exchange each year nowadays (10-20 per year in France), adverse events are very rare and recent advances in plasma exchange technologies, like immunoadsorption, might, in the future, counterbalance their cost and broaden their place in the therapeutic armamentarium for SLE.

The heart can be involved in vasculitides but the frequency of its involvement and the manifestations vary according to the vasculitis. Cardiovascular manifestations include cardiomyopathy (specific or resulting from myocardial infarctions), coronary arteritis (with risk of aneurysms, stenoses and thrombosis formation or rupture), pericarditis, valvulitis, conduction-tissue involvement (with heart blocks), arrhythmias (mainly supraventricular) and/or dissection of the aorta (and/or its proximal branches). As many of these manifestations are clinically silent, at least during their early stages, heart function should be systematically assessed in vasculitis patients, with at least ECG and echocardiography, and more invasive exploratory procedures when the former reveal abnormalities or symptoms become manifest. Specific cardiomyopathy has been identified as a factor of poor outcome in small and medium-sized vessel vasculitides (five-factor score). Therefore, in addition to symptomatic treatments, prescription of corticosteroids and immunosuppressants (mainly cyclophosphamide) is considered mandatory. This regimen has dramatically improved the overall prognosis of affected patients.

Endobronchial stenoses are rare in the course of Wegener's granulomatosis, and they occur even more rarely than subglottic stenoses.We report seven cases of endobronchial stenoses in the setting of Wegener granulomatosis. Neither the pulmonary symptoms nor the systemic manifestations of vasculitis were specific. However 6/7 patients presented a wheezing or an hemoptysis. Bronchial endoscopy has permitted the diagnosis in all cases. Local evolution was cicatricial and symptomatic stenosis in 3 cases (42,8%).Thus these lesions must be research in any case of pulmonary abnormality in the course of Wegener's granulomatosis, because they may lead to a pejorative prognosis. Moreover general and local treatment must be given early (at the inflammatory stage). After this stage, the local treatments are difficult and not efficient.

Focal myositis constitutes an original and rare pathological entity, characterized by a localized inflammation within skeletal muscle, presenting as a soft tissue painful tumefaction. Diagnosis requires histological confirmation because of its non-specific clinical feature and the numerous differential diagnoses.We report a 27 year-old man who presented with suggestive symptoms of focal myositis. MR imaging and echography were compatible with this diagnosis but also demonstrated the existence of a vascular component within the tumefaction. The diagnosis of a benign vascular malformation with intramuscular development was made by a surgically guided biopsy.Vascular malformations are histologically heterogeneous with extremely variable clinical expressions. When they develop within skeletal muscle, they may mimic focal myositis. Hence, their diagnosis has to be evoked before performing muscle biopsy, because of the potential hemorrhagic risk.

Langerhans'cell histiocytosis is a rare and mainly pediatric disease. Patients with hepatic involvement usually have a disseminated form of the disease, with poor prognosis. Sclerosing cholangitis can occur in 10 to 15% of multivisceral Langerhans'cell histiocytosis. We report the case of a 56-years-old patient who developed sclerosing cholangitis 12 years after the diagnosis of Langerhans'cell histiocytosis.A 56-years-old man was admitted because of rapid general health impairment with epigastric pain. He was diagnosed as having Langerhans'cell histiocytosis 12 years ago because of a diabetes insipidus. Lungs were involved and during follow-up vertebral osteocondensation also developed. However, Langerhans'cell histiocytosis was clinically silent at the time of admission, without any treatment. Biologically, cholestasis and inflammation were noted. Digestive radiological investigations (echo-endoscopy, CT-scan, MRI) showed homogenous hepatomegaly and a diffuse infiltration of intra and extrahepatic bile ducts. Liver biopsy yielded the diagnosis of sclerosing cholangitis. Clinical and biological improvement occurred with oral corticosteroids (at 12 months after sclerosing cholangitis diagnosis).Sclerosing cholangitis is a potential complication of Langerhans'cell histiocytosis, mainly in its multivisceral form. It can occur at a median of 2 years after diagnosis in children, but occasionally much later in adults, whereas Langerhans'cell histiocytosis seems quiescent. Diagnosis is supported by radiological investigations and liver biopsy. As no drug therapy appears clearly effective, liver transplantation must frequently be considered in these patients.