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3.
Am J Transplant ; 16(12): 3416-3429, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27172087

RESUMEN

Pretransplant autoantibodies to LG3 and angiotensin II type 1 receptors (AT1R) are associated with acute rejection in kidney transplant recipients, whereas antivimentin autoantibodies participate in heart transplant rejection. Ischemia-reperfusion injury (IRI) can modify self-antigenic targets. We hypothesized that ischemia-reperfusion creates permissive conditions for autoantibodies to interact with their antigenic targets and leads to enhanced renal damage and dysfunction. In 172 kidney transplant recipients, we found that pretransplant anti-LG3 antibodies were associated with an increased risk of delayed graft function (DGF). Pretransplant anti-LG3 antibodies are inversely associated with graft function at 1 year after transplantation in patients who experienced DGF, independent of rejection. Pretransplant anti-AT1R and antivimentin were not associated with DGF or its functional outcome. In a model of renal IRI in mice, passive transfer of anti-LG3 IgG led to enhanced dysfunction and microvascular injury compared with passive transfer with control IgG. Passive transfer of anti-LG3 antibodies also favored intrarenal microvascular complement activation, microvascular rarefaction and fibrosis after IRI. Our results suggest that anti-LG3 antibodies are novel aggravating factors for renal IRI. These results provide novel insights into the pathways that modulate the severity of renal injury at the time of transplantation and their impact on long-term outcomes.


Asunto(s)
Autoanticuerpos/sangre , Funcionamiento Retardado del Injerto/etiología , Supervivencia de Injerto/inmunología , Proteoglicanos de Heparán Sulfato/inmunología , Trasplante de Riñón/efectos adversos , Daño por Reperfusión/etiología , Animales , Autoanticuerpos/inmunología , Funcionamiento Retardado del Injerto/sangre , Funcionamiento Retardado del Injerto/patología , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Fallo Renal Crónico/cirugía , Pruebas de Función Renal , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Pronóstico , Daño por Reperfusión/sangre , Daño por Reperfusión/patología , Estudios Retrospectivos , Factores de Riesgo
4.
Neurohospitalist ; 5(4): 253-4, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26425254
5.
Nat Commun ; 2: 432, 2011 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-21847106

RESUMEN

The origin of pairing in a superconductor resides in the underlying normal state. In the cuprate high-temperature superconductor YBa(2)Cu(3)O(y) (YBCO), application of a magnetic field to suppress superconductivity reveals a ground state that appears to break the translational symmetry of the lattice, pointing to some density-wave order. Here we use a comparative study of thermoelectric transport in the cuprates YBCO and La(1.8-x)Eu(0.2)Sr(x)CuO(4) (Eu-LSCO) to show that the two materials exhibit the same process of Fermi-surface reconstruction as a function of temperature and doping. The fact that in Eu-LSCO this reconstruction coexists with spin and charge modulations that break translational symmetry shows that stripe order is the generic non-superconducting ground state of hole-doped cuprates.

6.
Rev Med Interne ; 25(8): 556-61, 2004 Aug.
Artículo en Francés | MEDLINE | ID: mdl-15276287

RESUMEN

PURPOSE: The aim of this study was to describe the present clinical characteristics of the pernicious anemia (PA). METHOD: It is a retrospective (1996-2002) multicenter (five departments of internal medicine) study of 49 patients presenting an established cobalamin deficiency related to PA. RESULTS: The median age of the patients was 74 years (25-93), the female/male ratio 2:9. Several autoimmune disorders were noted in 35% of the patients. Various clinical manifestations, mainly neurological, cutaneous and thrombotic, were found in 65.4% of the patients, at least one hematological abnormalities in 100%. Average serum vitamin B12 and homocystein levels were with 73 pg/ml (20-1960) and 42.9 micromol/l (7, 8-124). Anti-intrinsic factor or anti-parietal gastric cells antibodies were found in 87.5% and 62% of the patients (at least one antibody, in 96%) abnormal Schilling's test results in 86%. All the followed patients were successful treated with intramuscular (n = 27) or oral crystalline cyanocobalamin (n = 5). CONCLUSIONS: PA was associated with several autoimmune disorders; PA may be responsible of various clinical manifestations or biological abnormalities; and oral crystalline cyanocobalamin treatment may be successful.


Asunto(s)
Anemia Perniciosa/patología , Enfermedades Autoinmunes/complicaciones , Vitamina B 12/uso terapéutico , Adulto , Edad de Inicio , Anciano , Anemia Perniciosa/complicaciones , Anemia Perniciosa/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Prueba de Schilling , Factores Sexuales
7.
Eur J Intern Med ; 12(5): 459-461, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11557335

RESUMEN

We report the case of a patient with giant cell arteritis associated with cognitive dysfunction. Magnetic resonance imaging showed areas of subcortical increased signalling, suggesting intracerebral angiitis. Steroid and heparin therapy resulted in spectacular improvement in clinical status, and MRI abnormalities regressed almost completely. Intracranial localization of giant cell arteritis and the possible association of giant cell arteritis with primary angiitis of the central nervous system are discussed.

8.
Rev Med Interne ; 22(6): 536-41, 2001 Jun.
Artículo en Francés | MEDLINE | ID: mdl-11433562

RESUMEN

PURPOSE: To analyze the context in which acute colonic pseudo-obstructions occur in a medical practice. METHOD: Retrospective study of patients with an acute colonic pseudo-obstruction hospitalized in an internal medicine department between November 1992 and December 1999. RESULTS: We found 12 patients including eight men (mean age: 80.2 years). All had abdominal pains. Seven patients presented an occlusive syndrome. A septic shock occurred in two subjects. The average diameter of the cecum was 10 cm. Distention involved the whole colon for nine patients, and only the left part for three. Six subjects were affected by a bronchopneumonia, three had a previous history of recent diarrhea, two had colonic diverticulitis, and two others had a diabetic neuropathy. Ogilvie's syndrome revealed hypothyroidism for one patient. Nine patients were taking one or more medications incriminated in the acute colonic pseudo-obstruction: calcium-channel blockers (n = 6), neuroleptics (n = 5), antidepressant agents (n = 4), dopaminergic drugs (n = 2) and opiates (n = 1). Five patients underwent a colonoscopic decompression. Surgical procedures were undertaken for three patients: one underwent a complete colectomy because of numerous perforation. Except for the colectomized patient, the outcome resulted in either recovery (n = 7), partial improvement (n = 3), or recurrence (n = 1). CONCLUSION: In a medical environment, acute colonic pseudo-obstruction is a pathology for elderly persons, namely with a masculine predominance and often associated with iatrogenic factors. The outcome is more often than not favorable, but it may result in invasive acts or significant complications at this age.


Asunto(s)
Seudoobstrucción Colónica/etiología , Seudoobstrucción Colónica/patología , Dolor Abdominal/etiología , Enfermedad Aguda , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Colectomía , Femenino , Humanos , Hipotiroidismo , Enfermedad Iatrogénica , Masculino , Persona de Mediana Edad , Neumonía/complicaciones , Pronóstico , Estudios Retrospectivos , Factores Sexuales , Choque Séptico , Resultado del Tratamiento
10.
Invest Ophthalmol Vis Sci ; 42(5): 885-94, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11274063

RESUMEN

PURPOSE: To develop a means for noninvasive in vivo visualization of the ciliary processes using very-high-frequency (50 MHz) ultrasound and to develop quantitative morphologic descriptors that may relate to physiologic function. METHODS: The region of the ciliary body was scanned with very-high-frequency ultrasound, both in rabbits and in normal human subjects. Data were acquired in a series of planes so that the spacing between them was less than the beam width of the transducer in its focal plane. Three-dimensional perspective images were constructed, representing the anatomy of the angle region, including the ciliary processes. The automatically detected boundaries of the ciliary processes were analyzed to compute their periphery, area, shape factor, and fractal dimension. These measures were compared between the human and the rabbit eye and analyzed for periodicities related to the spacing of successive processes. RESULTS: Three-dimensional images allowed visualization of the radial arrangement of the processes. All biometric descriptors were significantly different between the rabbit and human eye and showed periodicities consistent with spacing between processes. CONCLUSIONS: The methods described in this report are sensitive descriptors of the state of the ciliary processes. These techniques may be of value in measurement of changes in the ciliary body associated with disease, medical therapy, and aging.


Asunto(s)
Cuerpo Ciliar/diagnóstico por imagen , Animales , Cuerpo Ciliar/anatomía & histología , Humanos , Imagenología Tridimensional/métodos , Músculo Liso/anatomía & histología , Músculo Liso/diagnóstico por imagen , Epitelio Pigmentado Ocular/anatomía & histología , Epitelio Pigmentado Ocular/diagnóstico por imagen , Conejos , Ultrasonografía/métodos
11.
J Refract Surg ; 16(4): 414-30, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10939721

RESUMEN

PURPOSE: To test and demonstrate measurement precision, imaging resolution, 3D thickness mapping, and clinical utility of a new prototype 3D very high-frequency (VHF) (50 MHz) digital ultrasound scanning system for corneal epithelium, flap, and residual stromal thickness after laser in situ keratomileusis (LASIK). METHODS: VHF ultrasonic 3D data was acquired by arc-motion, meridional scanning within a 10-mm zone. Digital signal processing techniques provided high-resolution B-scan imaging, and I-scan traces for high-precision pachymetry in 4 eyes. Thickness maps of individual corneal layers were constructed. Reproducibility of epithelial, flap, and full corneal pachymetry was assessed for single-point and 3D thickness mapping by repeated measures. Thickness mapping of the epithelium, stroma, flap, and full cornea were determined before and after LASIK. Preoperative to postoperative difference maps for epithelium, flap, and stroma were produced to demonstrate anatomical changes in the thickness profile of each layer. RESULTS: Surface localization precision was 0.87 microm. Central reproducibility for single-point pachymetry of epithelium was 0.61 microm; flap, 1.14 microm; and full cornea, 0.74 microm. Reproducibility for central pachymetry on 3D thickness mapping was 0.5 microm for epithelium and 1.5-microm for full cornea. B-scans and 3D thickness maps after LASIK demonstrated resolution of epithelial, stromal component of the flap, and residual stromal layers. Large epithelial profile changes were demonstrated after LASIK. Topographic variability of flap thickness and residual stromal thickness were significant. CONCLUSIONS: VHF digital ultrasound arc-B scanning provides high-resolution imaging and high-precision three-dimensional thickness mapping of corneal layers, enabling accurate anatomical evaluation of the changes induced in the cornea by LASIK.


Asunto(s)
Sustancia Propia/diagnóstico por imagen , Topografía de la Córnea , Epitelio Corneal/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Queratomileusis por Láser In Situ , Errores de Refracción/diagnóstico por imagen , Sustancia Propia/cirugía , Epitelio Corneal/cirugía , Humanos , Procesamiento de Imagen Asistido por Computador/normas , Procedimientos Quirúrgicos Refractivos , Reproducibilidad de los Resultados , Ultrasonografía
13.
Rev Med Interne ; 21(3): 231-5, 2000 Mar.
Artículo en Francés | MEDLINE | ID: mdl-10763183

RESUMEN

PURPOSE: Retinal vein occlusion has several causes. Cardiovascular risk factors, particularly systemic hypertension; as well as thrombophilia appear to be involved in the development of retinal vein occlusion. METHODS: In a retrospective study we analyzed these factors in 24 patients, admitted for retinal vein occlusion and isovolaemic hemodilution in an internal medicine unit. RESULTS: In patients over 50 years of age, cardiovascular risk factors predominate; while in patients under 50, one patient out of two has biological features indicating a risk for thrombosis. CONCLUSION: Serological abnormalities could be involved in the physiopathology of retinal vein occlusion in young patients.


Asunto(s)
Enfermedades Cardiovasculares/complicaciones , Glaucoma/complicaciones , Hipertensión/complicaciones , Oclusión de la Vena Retiniana/etiología , Trombofilia/complicaciones , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Hemodilución , Humanos , Masculino , Persona de Mediana Edad , Oclusión de la Vena Retiniana/sangre , Oclusión de la Vena Retiniana/terapia , Estudios Retrospectivos , Factores de Riesgo
15.
J Clin Microbiol ; 37(12): 4012-9, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10565923

RESUMEN

Staphylococcus aureus was isolated as the predominant or only isolate from cultures of stools of 60 patients over 2 years in a university hospital, leading to the collection of 114 isolates. Diarrhea was observed in 90% of the patients. Ninety-eight percent of the patients had received antibiotics in the month before the diarrhea. Ninety-two percent of the S. aureus isolates were methicillin resistant. S. aureus was encountered with antibiotic-associated diarrhea among 47 quite elderly patients affected or not affected by a gastrointestinal disease. Among the antimicrobial treatments, cessation of the previous therapy when possible or rapid application of oral vancomycin therapy was the most appropriate. Analysis of total DNA by pulsed-field gel electrophoresis revealed 27 different SmaI pulsotypes distributed in 15 clusters. The pulsotypes never differed for related isolates from a single patient, even if they originated from patients with bacteremia. S. aureus was not isolated as the predominant isolate in cultures of stools of 57 patients who received an antimicrobial treatment for more than 5 days without diarrhea. Occurence of production of both enterotoxin A and the bicomponent leucotoxin LukE-LukD by the S. aureus isolates was significantly different from that by random isolates. The results strongly suggest that when predominant in stool samples, S. aureus should be considered a possible etiologic agent for some cases of antibiotic-associated diarrhea.


Asunto(s)
Antibacterianos/efectos adversos , Proteínas Bacterianas , Diarrea/etiología , Diarrea/microbiología , Enterotoxinas/biosíntesis , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Clostridioides difficile/aislamiento & purificación , Electroforesis en Gel de Campo Pulsado , Enterocolitis Seudomembranosa/microbiología , Exotoxinas/biosíntesis , Heces/microbiología , Femenino , Humanos , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Staphylococcus aureus/clasificación , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
17.
Ophthalmology ; 105(2): 300-6, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9479291

RESUMEN

OBJECTIVE: The aim of this report is to describe the technology of three-dimensional (3-D) ultrasonic imaging and its impact on improved diagnosis and monitoring of ocular disease. DESIGN: The authors reviewed techniques for acquiring and displaying 3-D ultrasound data of the eye. PARTICIPANTS: The authors applied these techniques to representative individual cases, including a choroidal hemorrhage, a ciliary body melanoma, a ciliary body detachment, a displaced posterior chamber intraocular lens, and topographic analysis of a normal cornea. INTERVENTION: A computer-controlled motion system was used to perform very high-frequency (VHF) (50-MHz) and conventional (10-MHz) digital 3-D ultrasound data collection. The scanning system allowed digitization of ultrasound data from a series of parallel planes. The 3-D data could be manipulated interactively to obtain two-dimensional images in any plane through the scan volume. The 3-D images were constructed by volume rendering and could be positioned for viewing from a variety of perspectives. The 3-D ultrasound parameter images representing acoustic scatterer properties were generated by spectrum analysis of digitized echo data. Color maps representing the contour and thickness of the epithelium and stroma of the central corneal were generated by digital signal processing of 3-D echo data. RESULTS: Quantitative volume measurement and biometric techniques enhanced the diagnostic and treatment planning information content in 3-D ultrasound images. The location and extent of hemorrhage and clots within the suprachoroidal space were shown with solid modeling. Volume changes in ciliary body melanoma over time were documented and 3-D ultrasound parameter image changes associated with radiation therapy observed. In ciliary body detachment, the extent of the detachment was shown. Solid modeling of a posterior chamber intraocular lens showed misplacement of the haptic in relation to the lens capsule remnants. Keratopachymetric maps showed the range and variance of thickness and local radius of curvature measurements in the cornea. CONCLUSIONS: Quantitative volume measurement and biometric tools combined with segmentation of 3-D ultrasound images improve diagnostic and treatment planning informational content of 3-D ultrasound images through improved localization of tissue structures.


Asunto(s)
Oftalmopatías/diagnóstico por imagen , Ultrasonografía/métodos , Hemorragia de la Coroides/diagnóstico por imagen , Cuerpo Ciliar/diagnóstico por imagen , Topografía de la Córnea/métodos , Migración de Cuerpo Extraño/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador , Lentes Intraoculares , Melanoma/diagnóstico por imagen , Enfermedades de la Úvea/diagnóstico por imagen , Neoplasias de la Úvea/diagnóstico por imagen
18.
Radiol Clin North Am ; 36(6): 1073-82, x, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9884689

RESUMEN

New ultrasound technologies, including three-dimensional imaging, tissue characterization, and very high frequency (50 MHz) ultrasound, have become available recently. We demonstrate how these technologies can be used alone and together to improve the use of ultrasound for diagnosis of ocular pathology.


Asunto(s)
Oftalmopatías/diagnóstico por imagen , Ojo/diagnóstico por imagen , Humanos , Aumento de la Imagen/instrumentación , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Ciencia del Laboratorio Clínico/métodos , Ultrasonido/clasificación , Ultrasonografía/instrumentación , Ultrasonografía/métodos
19.
Retina ; 17(2): 109-17, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9143038

RESUMEN

PURPOSE: This report describes results of a prospective pilot trial to evaluate the safety and efficacy of hyperthermia as an adjunct to enucleation or brachytherapy in the treatment of patients with intraocular malignant melanoma. METHODS: Twenty-five patients with intraocular malignant melanomas were treated with ultrasonically induced hyperthermia. In 14 patients, hyperthermia was administered before enucleation (median follow-up period, 44 months), and in 11 patients, hyperthermia was used as an adjunct to brachytherapy (median follow-up period, 79 months). RESULTS: Patient survival in each group was compared with that of a control group treated with enucleation or brachytherapy alone, using Kaplan-Meier and Cox analysis. Taking into account the simultaneous effects of tumor size and location, the relative risk ratios and 95% confidence bounds associated with adjunctive hyperthermia were 1.68 (range, 0.60-4.72) and 0.68 (range, 0.16-2.89) for the enucleation and brachytherapy groups, respectively. CONCLUSIONS: Patients receiving adjunctive hyperthermia with brachytherapy showed increased survival, whereas those receiving hyperthermia before enucleation showed decreased survival. Neither trend was statistically significant in this small series. The synergism of hyperthermia with radiation may offer the possibility of improved tumor management.


Asunto(s)
Hipertermia Inducida/métodos , Melanoma/terapia , Terapia por Ultrasonido/métodos , Neoplasias de la Úvea/terapia , Braquiterapia/métodos , Enucleación del Ojo , Estudios de Seguimiento , Humanos , Melanoma/mortalidad , Melanoma/radioterapia , Melanoma/cirugía , Proyectos Piloto , Estudios Prospectivos , Radioterapia Adyuvante , Análisis de Regresión , Factores de Riesgo , Seguridad , Tasa de Supervivencia , Resultado del Tratamiento , Neoplasias de la Úvea/mortalidad , Neoplasias de la Úvea/radioterapia , Neoplasias de la Úvea/cirugía
20.
Ultrasound Med Biol ; 23(4): 573-81, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9232766

RESUMEN

Previous studies demonstrated a correlation between acoustic backscatter parameters and survival in ocular melanoma. The histologic presence of microvascular networks in ocular melanoma is also associated with death from metastases. This study tests the hypothesis that melanomas grouped on the basis of these microvascular patterns are separable by ultrasound spectrum analysis. We scanned 40 melanomas using a 10-MHz ultrasound unit equipped for digitization of radio frequency data. After enucleation, tumors were sectioned in planes corresponding to the ultrasonographic examination and stained to demonstrate microcirculation. Acoustic spectral parameters were compared between 14 melanomas with a nevuslike microcirculation and 26 with foci of high-risk microvascular structures. Smaller scatterer size, lower acoustic concentration and greater spatial variability were found to correlate with high-risk microvascular patterns and areas of cystic degeneration. We suggest that nonvascular extracellular matrix components associated with microvessels may be responsible for the correlation of acoustic parameters with microvascular pattern and distribution.


Asunto(s)
Neoplasias de la Coroides/diagnóstico por imagen , Cuerpo Ciliar , Melanoma/diagnóstico por imagen , Neoplasias de la Úvea/diagnóstico por imagen , Neoplasias de la Coroides/irrigación sanguínea , Cuerpo Ciliar/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador , Melanoma/irrigación sanguínea , Microcirculación/diagnóstico por imagen , Ultrasonografía , Neoplasias de la Úvea/irrigación sanguínea
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