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1.
Rev Neurol (Paris) ; 166(6-7): 565-73, 2010.
Artículo en Francés | MEDLINE | ID: mdl-20116812

RESUMEN

INTRODUCTION: Hemiplegic (or spastic unilateral) cerebral palsy accounts for about 30% of all cases of cerebral palsy. With a population prevalence of 0.6 per 1000 live births, it is the most common type of cerebral palsy among term-born children and the second most common type after diplegia among preterm infants. STATE OF THE ART: Many types of prenatal and perinatal brain injury can lead to congenital hemiplegia and brain MRI is the most useful tool to classify them with accuracy and to provide early prognostic information. Perinatal arterial ischemic stroke thus appears as the leading cause in term infants, whereas encephalopathy of prematurity is the most common cause in premature babies. Other causes include brain malformations, neonatal sinovenous thrombosis, parenchymal hemorrhage (for example due to coagulopathy or alloimmune thrombocytopenia) and the more recently described familial forms of porencephaly associated with mutations in the COL4A1 gene. PERSPECTIVES: In adjunction with pharmacologic treatment (botulinium neurotoxin injection), new evidence-based rehabilitational interventions, such as constraint-induced movement therapy and mirror therapy, are increasingly being used.


Asunto(s)
Parálisis Cerebral , Hemiplejía , Algoritmos , Toxinas Botulínicas Tipo A/uso terapéutico , Encéfalo/anomalías , Parálisis Cerebral/diagnóstico , Parálisis Cerebral/epidemiología , Parálisis Cerebral/rehabilitación , Terapia por Ejercicio , Enfermedades Fetales , Hemiplejía/diagnóstico , Hemiplejía/epidemiología , Hemiplejía/rehabilitación , Humanos , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/epidemiología , Espasticidad Muscular/etiología , Modalidades de Fisioterapia , Prevalencia , Factores de Riesgo , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/embriología
2.
Eur J Clin Microbiol Infect Dis ; 27(10): 959-68, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18594884

RESUMEN

Whipple's disease is a systemic chronic infection caused by Tropheryma whipplei. Asymptomatic people may carry T. whipplei in their digestive tract and this can be determined by PCR, making serological diagnosis useful to distinguish between carriers and patients. Putative antigenic proteins were selected by computational analysis of the T. whipplei genome, immunoproteomics studies and from literature. After expression, putative T. whipplei antigens were screened by microimmunofluorescence with sera of immunized rabbit. Selected targets were screened by microarray using sera from patients and carriers. Paradoxically, with 19 tested recombinant proteins and a glycosylated native protein of T. whipplei, a higher immune response was observed with asymptomatic carriers. In contrast, quantification of human IgA exhibited a higher reaction in patients than in carriers against 10 antigens. These results were used to design a diagnostic test with a cut-off value for each antigen. A blind test assay was performed and was able to diagnose 6/8 patients and 11/12 carriers. Among people with positive T. whipplei PCR of the stool, patients differ from carriers by having positive IgA detection and a negative IgG detection. If confirmed, this serological test will distinguish between carriers and patients in people with positive PCR of the stool.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Tropheryma/inmunología , Enfermedad de Whipple/diagnóstico , Portador Sano/diagnóstico , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Pruebas Serológicas/métodos , Tropheryma/aislamiento & purificación
3.
Magn Reson Chem ; 46(4): 342-6, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18306175

RESUMEN

Silicon-substituted hydroxyapatite (Si-HAp) has shown promising properties such as high-bone remodeling around implants. So far, the techniques used for the structural characterization of the Si-HAp have given indirect evidence of the presence of silicon inside the structure (by X-ray and neutron diffraction). In this paper, we focus on Si-HAp derivatives obtained by a precipitation method (widely described in the literature). We demonstrate here by solid-state NMR spectroscopy that only a fraction of the silicon atoms are incorporated into the HAp lattice in the form of Q(0) (SiO(4) (4-)) species, for 4.6 wt% Si-HAp. A large amount of silicate units are located outside the HAp structure and correspond to silica-gel units. All results were established through (29)Si MAS, (1)H -->(29)Si CP MAS and T(1)rho((1)H) edited (1)H -->(29)Si CP MAS experiments. This last pulse scheme acted as a powerful editing sequence, leading to unambiguous spectroscopic conclusions, concerning the location of the SiO(4) (4-) moieties.


Asunto(s)
Durapatita/química , Espectroscopía de Resonancia Magnética/métodos , Silicatos/química , Isótopos , Espectroscopía de Resonancia Magnética/normas , Modelos Moleculares , Difracción de Polvo , Protones , Estándares de Referencia , Silicio/química , Espectrofotometría Infrarroja/métodos
4.
J Magn Reson ; 187(1): 131-40, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17481933

RESUMEN

The complete set of NMR parameters for (17)O enriched phenylphosphinic acid C(6)H(5)HP( *)O(*OH) is calculated from first principles by using the Gauge Including Projected Augmented Wave (GIPAW) approach [C.J. Pickard, F. Mauri, All-electron magnetic response with pseudopotentials: NMR chemical shifts, Phys. Rev. B 63 (2001) 245101/1-245101/13]. The analysis goes beyond the successful assignment of the spectra for all nuclei ((1)H, (13)C, (17)O, (31)P), as: (i) the (1)H CSA (chemical shift anisotropy) tensors (magnitude and orientation) have been interpreted in terms of H bonding and internuclear distances. (ii) CSA/dipolar local field correlation experiments have allowed the orientation of the direct P-H bond direction in the (31)P CSA tensor to be determined. Experimental and calculated data were compared. (iii) The overestimation of the calculated (31)P CSA has been explained by local molecular reorientation and confirmed by low temperature static (1)H-->(31)P CP experiments.


Asunto(s)
Ácidos Fosfínicos/química , Algoritmos , Anisotropía , Simulación por Computador , Durapatita/química , Campos Electromagnéticos , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Isótopos de Oxígeno
5.
J Nutr Health Aging ; 21(10): 1133-1141, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29188872

RESUMEN

OBJECTIVES: Effect of 3 different dairy protein sources on the recovery of muscle function after limb immobilization in old rats. DESIGN: Longitudinal animal study. SETTING: Institut National de la Recherche Agronomique (INRA). The study took part in a laboratory setting. INTERVENTION: Old rats were subjected to unilateral hindlimb immobilization for 8 days and then allowed to recover with 3 different dietary proteins: casein, soluble milk proteins or whey proteins for 49 days. MEASUREMENTS: Body weight, muscle mass, muscle fibre size, isometric, isokinetic torque, muscle fatigability and muscle oxidative status were measured before and at the end of the immobilization period and during the recovery period i.e 7, 21, 35 and 49 days post immobilization. RESULTS: In contrast to the casein diet, soluble milk proteins and whey proteins were efficient to favor muscle mass recovery after cast immobilization during aging. By contrast, none of the 3 diary proteins was able to improve muscle strength, power and fatigability showing a discrepancy between the recovery of muscle mass and function. However, the soluble milk proteins allowed a better oxidative capacity in skeletal muscle during the rehabilitation period. CONCLUSION: Whey proteins and soluble milk proteins improve muscle mass recovery after immobilization-induced muscle atrophy in old rats but do not allow muscle functional property restoration.


Asunto(s)
Inmovilización/efectos adversos , Proteínas de la Leche/metabolismo , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Atrofia Muscular/terapia , Sarcopenia/terapia , Proteína de Suero de Leche/uso terapéutico , Animales , Estudios Longitudinales , Masculino , Ratas , Ratas Wistar , Sarcopenia/patología , Proteína de Suero de Leche/farmacología
6.
J Magn Reson ; 179(1): 114-9, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16343956

RESUMEN

We report the results of the two-dimensional MAS-J-HMQC experiment providing scalar correlations between 29Si and 31P nuclei in solid state NMR, and we give the first evaluation of the 2JSi-O-P coupling constants (approximately 15 Hz) for a crystalline silicophosphate phase Si5O(PO4)6. The experiment is applied to the characterization of complex mixtures of SiP2O7 phases, through editing of 31P spin pairs by the heteronuclear 2JP-O-Si interaction.

7.
Artículo en Inglés | MEDLINE | ID: mdl-27269711

RESUMEN

Mimicking the breast milk lipid composition appears to be necessary for infant formula to cover the brain's needs in n-3 PUFA. In this study, we evaluated the impact of partial replacement of vegetable oil (VL) in infant formula by dairy fat (DL) on docosahexaenoic acid (DHA) brain level, neuroplasticity and corticosterone in mice. Mice were fed with balanced VL or balanced DL diets enriched or not in DHA and arachidonic acid (ARA) from the first day of gestation. Brain DHA level, microglia number, neurogenesis, corticosterone and glucocorticoid receptor expression were measured in the offsprings. DL diet increased DHA and neuroplasticity in the brain of mice at postnatal day (PND) 14 and at adulthood compared to VL. At PND14, ARA and DHA supplementation increased DHA in VL but not in DL mice brain. Importantly, DHA and ARA supplementation further improved neurogenesis and decreased corticosterone level in DL mice at adulthood. In conclusion, dairy lipids improve brain DHA level and neuroplasticity.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Corticosterona/metabolismo , Grasas de la Dieta/administración & dosificación , Ácidos Docosahexaenoicos/metabolismo , Aceites de Plantas/administración & dosificación , Animales , Ácido Araquidónico/metabolismo , Encéfalo/metabolismo , Productos Lácteos , Grasas de la Dieta/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Lactante , Fórmulas Infantiles/química , Ratones , Modelos Animales , Plasticidad Neuronal/efectos de los fármacos , Aceites de Plantas/farmacología , Receptores de Glucocorticoides/efectos de los fármacos
8.
J Magn Reson ; 271: 46-51, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27544845

RESUMEN

Magic Angle Coil Spinning (MACS) aids improving the intrinsically low NMR sensitivity of heterogeneous microscopic samples. We report on the design and testing of a new type of monolithic 2D MACS resonators to overcome known limitations of conventional micro coils. The resonators' conductors were printed on dielectric substrate and tuned without utilizing lumped element capacitors. Self-resonance conditions have been computed by a hybrid FEM-MoM technique. Preliminary results reported here indicate robust mechanical stability, reduced eddy currents heating and negligible susceptibility effects. The gain in B1/P is in agreement with the NMR sensitivity enhancement according to the principle of reciprocity. A sensitivity enhancement larger than 3 has been achieved in a monolithic micro resonator inside a standard 4mm rotor at 500MHz. These 2D resonators could offer higher performance micro-detection and ease of use of heterogeneous microscopic substances such as biomedical samples, microscopic specimens and thin film materials.

9.
Lab Chip ; 16(7): 1157-60, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-26974287

RESUMEN

The effect of mixing calcium and oxalate precursors by diffusion at miscible liquid interfaces on calcium oxalate crystalline phases, and in physiological conditions (concentrations and flow rates), is studied using a microfluidic channel. This channel has similar dimensions as the collection duct in human kidneys and serves as a biomimetic model in order to understand the formation of pathological microcalcifications.


Asunto(s)
Biomimética , Calcinosis/patología , Oxalato de Calcio/química , Precipitación Química , Difusión , Riñón/patología , Técnicas Analíticas Microfluídicas , Oxalato de Calcio/aislamiento & purificación , Humanos , Técnicas Analíticas Microfluídicas/instrumentación , Tamaño de la Partícula , Propiedades de Superficie
10.
Clin Neuropharmacol ; 23(3): 133-42, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10895396

RESUMEN

The ability of transdermal administration of the dopamine D2/D3 agonist piribedil (1-[3,4-methylenedioxybenzyl)]-4-[(2-pyrimidinyl)]piperazine) to reverse hypokinesia and other motor deficits observed in MPTP-treated common marmosets was investigated. Piribedil (2.5-10.0 mg/animal), applied directly to the skin of the abdomen as a paste, produced a long-lasting and concentration-dependent reversal of motor deficits. The antiparkinsonian actions of piribedil occurred within 10 minutes of drug administration and lasted as long as 10 hours. Transdermally applied piribedil produced a pattern of locomotor activity characteristic of normal motor behavior in this species. Symptoms of nausea (marked excessive salivation, retching, and/or vomiting) were not observed after transdermal application of piribedil. Additionally, pretreatment with the peripheral dopamine antagonist domperidone enhanced the antiparkinsonian effects of piribedil. Application to the skin of monolayer or bilayer patches impregnated with piribedil also produced a marked increase in locomotor activity and reversal of motor deficits. After application of various patch fractions (whole, one-half, or one-fourth), the increase in locomotor activity and reversal of disability correlated well with the surface area of skin covered. Measurement of serum levels of piribedil after single application of bilayer patches showed a positive relationship between drug levels and antiparkinsonian activity. Repeated daily application of piribedil bilayer patches for 5 days to MPTP-treated common marmosets primed to show dyskinesia by previous exposure to L-Dopa produced antiparkinsonian activity accompanied by dyskinetic movements. Transdermal administration of dopamine agonists such as piribedil may provide a useful means of producing a long-lasting reversal of motor deficits in Parkinson's disease while avoiding acute adverse effects such as nausea.


Asunto(s)
1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/antagonistas & inhibidores , Antiparkinsonianos/farmacología , Dopaminérgicos/farmacología , Discinesia Inducida por Medicamentos/prevención & control , Piribedil/farmacología , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacología , Administración Cutánea , Animales , Antiparkinsonianos/administración & dosificación , Antiparkinsonianos/sangre , Callithrix , Femenino , Hipocinesia/inducido químicamente , Hipocinesia/prevención & control , Masculino , Actividad Motora/efectos de los fármacos , Piribedil/administración & dosificación , Piribedil/sangre
11.
Cancer Radiother ; 1(4): 314-22, 1997.
Artículo en Francés | MEDLINE | ID: mdl-9435822

RESUMEN

PURPOSE: Financial costs from "Z" procedures were evaluated and compared with the amount of direct costs that are needed for the annual activity of a radiation oncology department. MATERIALS AND METHODS: The various components, particularly staff earnings that are estimated for each procedure according to their category and working time, were cumulated for calculation of direct loads. RESULTS: Comparisons between direct expenses and the total amount of Z procedures led to the following results: the global cost is the same; at analysis of therapeutic procedures, however, this apparent similarity masks some very significant gaps; valorization of Z procedures is much lower than that of the corresponding real loads, especially when therapeutic procedures are quite different from techniques that are considered as "standard"; these differences do not apply to all the components of radiation therapy procedures. In particular, medical steps would be uniformly underestimated, while irradiation per se is overestimated. CONCLUSION: The authors suggest modifications of the general objectives and items of the nomenclature of radiotherapy and brachytherapy procedures.


Asunto(s)
Neoplasias , Radioterapia/economía , Braquiterapia/economía , Costos y Análisis de Costo , Diseño de Equipo , Humanos , Neoplasias/economía , Neoplasias/radioterapia , Oncología por Radiación/economía , Salarios y Beneficios
12.
Therapie ; 55(5): 635-41, 2000.
Artículo en Francés | MEDLINE | ID: mdl-11201979

RESUMEN

We investigated the frequency of ADRs occurring during one year (1995) in a French regional cancer institute. Patients with at least one ADR leading to or occurring during hospitalization in the institute were identified by searching diagnosis codes potentially related to an adverse drug reaction in the hospital medical database of the PMSI (Programme de médicalisation des Systèmes d'Information). We found 435 hospitalizations relative to 285 patients (6.2 per cent of the whole population of inpatients in 1995 and 3.1 per cent of stays in 1995). The total cost to treat ADRs was 1.7 per cent of the total budget of the hospital with a median cost of 8517 francs (mean cost: 13,271 +/- 15,330 francs). The highest cost was due to medical staff, blood transfusions, and anti-infectious drugs, despite the use of prophylactic agents. These results emphasize the high incidence and excess costs of ADRs related to anticancer chemotherapy.


Asunto(s)
Antineoplásicos/efectos adversos , Instituciones Oncológicas/estadística & datos numéricos , Adulto , Sistemas de Registro de Reacción Adversa a Medicamentos , Anciano , Instituciones Oncológicas/economía , Manejo de Caso , Bases de Datos Factuales , Grupos Diagnósticos Relacionados , Utilización de Medicamentos , Femenino , Francia/epidemiología , Costos de Hospital , Humanos , Incidencia , Pacientes Internos , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/economía
13.
Ann Endocrinol (Paris) ; 60(5): 408-13, 1999 Nov.
Artículo en Francés | MEDLINE | ID: mdl-10615520

RESUMEN

The French hospital reform requires the development of different activities indicators which may be utilized by hospitals in order to negotiate reorganizations and redistributions. The French-DRG's classification is a useful tool in this type of negotiation as it allows the description of an activity and the evaluation of its budget. Nevertheless, it is insufficient in taking into account high-cost patients. The clinical characterization of high-cost subgroups completes the DRG description. We studied the length of stays of 801 discharge reports of the 418 French DRG "diabetes, age > 36 years" of the Amiens University Hospital for 1996. It showed that this DRG is made up of 3 subgroups, of which the most costly gathers 14% of all patients. Criteria which were significantly linked with this third subgroup were: the number of comorbidities by RSS and the number of diabetes complications by RSS.


Asunto(s)
Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/terapia , Tiempo de Internación , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
14.
Ann Urol (Paris) ; 34(1): 32-8, 2000 Feb.
Artículo en Francés | MEDLINE | ID: mdl-10763422

RESUMEN

OBJECTIVE: To evaluate the safety and long-term efficacy of curative-intent radiation therapy in patients with apparently localized prostate cancer. METHOD: 48 patients with T < 3 M0 prostate cancer recruited between 1981 and 1985 received regular clinical follow-up for at least ten years or until their death. Radiation therapy was given according to the protocols established by Ray and Bagshaw. RESULTS: Radiation therapy was safe and effective in most patients. The rate of escape phenomenon was less than 10% after two years. Tumor control rates were greater than 80% after five years and 50% after ten years. Unfortunately, local remission, even when prolonged, did not necessarily indicate a complete cure: 20% of local recurrences developed five to 11 years after radiation therapy. CONCLUSION: Radiation therapy may be the best first-line treatment in men older than 75 years of age and in those whose life expectancy seems shorter than ten years, but should probably not be considered curative.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/mortalidad , Tasa de Supervivencia , Factores de Tiempo
15.
J Nutr Health Aging ; 17(7): 619-23, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23933873

RESUMEN

Interventions are crucial as they offer simple and inexpensive public health solutions that will be useful over the long term use. A Task Force on designing trials of nutritional interventions to slow cognitive decline in older adults was held in Toulouse in September 2012. The aim of the Task Force was to bring together leading experts from academia, the food industry and regulatory agencies to determine the best trial designs that would enable us to reach our goal of maintaining or improving cognitive function in apparently healthy aging people. An associated challenge for this Task Force was to determine the type of trials required by the Public Food Agencies for assessing the impact of nutritional compounds in comparison to well established requirements for drug trials. Although the required quality of the study design, rationale and statistical analysis remains the same, the studies designed to show reduction of cognitive decline require a long duration and the objectives of this task force was to determine best design for these trials. Two specific needs were identified to support trials of nutritional interventions: 1- Risk- reduction strategies are needed to tackle the growing burden of cognitive decline that may lead to dementia, 2- Innovative study designs are needed to improve the quality of these studies.


Asunto(s)
Trastornos del Conocimiento/prevención & control , Cognición , Demencia/prevención & control , Dieta , Proyectos de Investigación , Academias e Institutos , Comités Consultivos , Necesidades y Demandas de Servicios de Salud , Humanos , Resultado del Tratamiento
16.
Acta Biomater ; 6(8): 3264-74, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20188871

RESUMEN

Four samples of composition Ca(10)(PO(4))(6-x)(SiO(4))(x)(OH)(2-x), with x=0.0, 0.1, 0.2 and 0.5, were prepared and characterized using powder X-ray and neutron powder diffraction, and (1)H, (31)P and (29)Si nuclear magnetic resonance (NMR) spectroscopy. The composition of the Si-substituted HAp phases was determined by joint Rietveld refinements from powder X-ray and powder neutron diffraction data. Taking into account electroneutrality, a chemical formula for the Si-substituted HAp phases with indication of the incorporated silicate amount is proposed. Solid-state (29)Si NMR confirms the presence of only Q(0) species, in good agreement with the presence of substituted HAp and beta-TCP phases only. Thanks to NMR spectroscopy, two types of protons in the Si-substituted HAp phase were identified, the new site corresponding to species engaged in hydrogen bonding with silicate anions. This allowed further refinement of the formulae for these phases with very good quantitative agreement for populations derived from the refinement and integration of NMR data.


Asunto(s)
Fosfatos de Calcio/química , Cerámica/química , Ensayo de Materiales/métodos , Silicio/química , Espectroscopía de Resonancia Magnética , Transición de Fase , Polvos , Difracción de Rayos X
19.
Oncogene ; 27(32): 4497-502, 2008 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-18372917

RESUMEN

The homeobox gene Cdx1 is involved in anteroposterior patterning in embryos and its expression selectively persists in the intestinal epithelium throughout life. In human colon cancers, Cdx1 is overexpressed in few cases and lost in the majority of adenocarcinomas. We used mouse models of gain and loss-of-function to investigate the role of Cdx1 in intestinal development and cancers. Transgenic mice overexpressing Cdx1 and knockout mice exhibited a morphologically normal intestine. Cell proliferation, specification into the four differentiated lineages and migration along the crypt-villus axis were unchanged compared to wild-type mice. Changing Cdx1 caused an inverse and dose-dependent modification of the expression of the paralogous gene Cdx2, indicating that Cdx1 fine-tunes Cdx2 activity. Transgenenic and knockout mice failed to spontaneously develop tumours. Overexpressing Cdx1 was without incidence on the frequency of intestinal tumours induced chemically by azoxymethane treatment or genetically in Apc(Delta14/+) mice. However, it augmented the severity of the tumours in Apc(Delta14/+) mice. Inversely, the loss-of-function of Cdx1 in knockout mice was without incidence on the growth of tumours induced by azoxymethane. We conclude that Cdx1 is dispensable for intestinal development and that its overexpression could increase malignancy in early stages of tumourigenesis.


Asunto(s)
Genes Homeobox , Proteínas de Homeodominio/fisiología , Neoplasias Intestinales/etiología , Intestinos/embriología , Animales , Azoximetano/toxicidad , Factor de Transcripción CDX2 , Genes APC , Proteínas de Homeodominio/genética , Neoplasias Intestinales/genética , Ratones , Ratones Transgénicos , Factores de Transcripción/fisiología
20.
Inorg Chem ; 46(4): 1379-87, 2007 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-17291123

RESUMEN

One- and two-dimensional refocused MAS-J-INEPT NMR experiments in the solid state (through-bond polarization transfer) involving the highly abundant 31P spin and the rare 29Si spin are described for the crystalline silicophosphate phase Si5O(PO4)6 and complex mixtures of SiP2O7 polymorphs. The evaluation of the 2JP-O-Si coupling constants for all 29Si sites is obtained by the careful analysis of the INEPT build-up curves under fast MAS. The results are in agreement with the crystallographic data, taking into account the various J coupling paths. The efficiency of the experiment is demonstrated by its application to more complex systems such as silicophosphate amorphous gels (obtained by the sol-gel process).

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