RESUMEN
Xenomitochondrial mice harboring trans-species mitochondria on a Mus musculus domesticus (MD) nuclear background were produced. We created xenomitochondrial ES cell cybrids by fusing Mus spretus (MS), Mus caroli (MC), Mus dunni (Mdu), or Mus pahari (MP) mitochondrial donor cytoplasts and rhodamine 6-G treated CC9.3.1 or PC4 ES cells. The selected donor backgrounds reflected increasing evolutionary divergence from MD mice and the resultant mitochondrial-nuclear mismatch targeted a graded respiratory chain defect. Homoplasmic (MS, MC, Mdu, and MP) and heteroplasmic (MC) cell lines were injected into MD ova, and liveborn chimeric mice were obtained (MS/MD 18 of 87, MC/MD 6 of 46, Mdu/MD 31 of 140, and MP/MD l of 9 founder chimeras, respectively). Seven MS/MD, 1 MC/MD, and 11 Mdu/MD chimeric founder females were mated with wild-type MD males, and 18 of 19 (95%) were fertile. Of fertile females, only one chimeric MS/MD (1% coat color chimerism) and four chimeric Mdu/MD females (80-90% coat color chimerism) produced homoplasmic offspring with low efficiency (7 of 135; 5%). Four male and three female offspring were homoplasmic for the introduced mitochondrial backgrounds. Three male and one female offspring proved viable. Generation of mouse lines using additional female ES cell lineages is underway. We hypothesize that these mice, when crossbred with neurodegenerative-disease mouse models, will show accelerated age-related neuronal loss, because of their suboptimal capacity for oxidative phosphorylation and putatively increased oxidative stress.
Asunto(s)
ADN Mitocondrial/genética , Modelos Animales de Enfermedad , Ingeniería Genética/métodos , Ratones Transgénicos/genética , Mitocondrias/genética , Enfermedades Mitocondriales/genética , Enfermedades Neurodegenerativas/genética , Animales , Línea Celular , Femenino , Hibridación Genética/genética , Masculino , RatonesRESUMEN
OBJECTIVE: The purpose of this article is to report a previously undescribed MR imaging finding that is associated with osteochondral injuries of the knee. CONCLUSION: In adult patients, segmental absence of chemical shift artifact in the subchondral femoral condyles on T1-weighted MR images is associated with osteochondral fractures.
Asunto(s)
Cartílago Articular/lesiones , Fracturas del Fémur/diagnóstico , Traumatismos de la Rodilla/diagnóstico , Imagen por Resonancia Magnética , Adolescente , Adulto , Cartílago Articular/patología , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Traumatic diaphragmatic hernias can be difficult to diagnose because of their varied clinical and radiologic signs and because patients may not present with symptoms for months to years following the injury. We report a case of a delayed presentation of a traumatic diaphragmatic rupture through which a portion of the stomach herniated and simulated a large subphrenic abscess.
Asunto(s)
Hernia Diafragmática Traumática/diagnóstico , Absceso Subfrénico/diagnóstico , Adulto , Diagnóstico Diferencial , Urgencias Médicas , Hernia Diafragmática Traumática/diagnóstico por imagen , Humanos , Masculino , Tomografía Computarizada por Rayos XRESUMEN
Our purpose was to investigate three-dimensional (3D) gadolinium-enhanced magnetic resonance angiography (Gd-MRA) in the evaluation of renal transplant arteries. Eleven MR angiography examinations were performed in nine renal transplant patients. Gd-MRA, three-dimensional phase contrast (3D-PC) post-gadolinium, and two-dimensional time-of-flight (2D-TOF) MR angiography were performed and independently reviewed by three vascular radiologists who, for each MR angiography sequence, separately graded occlusive disease in the ipsilateral iliac artery, the transplant artery anastomosis, and the transplant artery itself. The Gd-MRA and 3D-PC data were reviewed as maximum intensity projections (MIP) reconstructed in standard planes, and the 2D-TOF data were interpreted from source images. In addition, a single vascular radiologist prospectively interpreted the Gd-MRA and 3D-PC data together, hereinafter Gd/PC, from MIP reconstructions for each case. In all of these patients either surgical (n = 3) or angiographic studies (n = 8) were performed within 21 days following the MR examination, which served as a reference standard to determine sensitivity and specificity. The sensitivity/specificity for the detection of significant stenosis were as follows: Gd-MRA, 67/88; 3D-PC, 60.3/76.6; 2D-TOF, 47/81; and Gd/PC, 100/100. The kappa statistic (kappa) for interobserver agreement for the grading of stenoses by 2D-TOF, Gd-PC, and Gd-MRA was 0.48, 0.60, and 0.74, respectively. The percentage of all vascular segments seen well enough to grade (cumulative for all three observers) was 94%, 85%, and 79% for Gd-MRA, 3D-PC, and 2D-TOF, respectively. The combination of Gd-MRA and 3D-PC is a promising approach to the evaluation of transplant renal arteries.
Asunto(s)
Medios de Contraste , Gadolinio , Aumento de la Imagen/métodos , Trasplante de Riñón/patología , Angiografía por Resonancia Magnética/métodos , Adolescente , Adulto , Anastomosis Quirúrgica , Angiografía , Arteriopatías Oclusivas/diagnóstico , Arteriopatías Oclusivas/diagnóstico por imagen , Combinación de Medicamentos , Femenino , Gadolinio DTPA , Compuestos Heterocíclicos , Humanos , Arteria Ilíaca/diagnóstico por imagen , Arteria Ilíaca/patología , Procesamiento de Imagen Asistido por Computador , Masculino , Meglumina , Variaciones Dependientes del Observador , Compuestos Organometálicos , Ácido Pentético/análogos & derivados , Estudios Prospectivos , Arteria Renal/diagnóstico por imagen , Arteria Renal/patología , Arteria Renal/cirugía , Obstrucción de la Arteria Renal/diagnóstico , Obstrucción de la Arteria Renal/diagnóstico por imagen , Sensibilidad y EspecificidadRESUMEN
The behavioral and cognitive effects of theophylline were studied in 14 asymptomatic asthmatic children. A double-blind crossover design was used with two dosage levels. Conners parent ratings suggest behavioral improvement by the second week of treatment, regardless of dosage or order of administration. No effects were found on cognitive measures. We conclude that the majority of behavior problems associated with theophylline occur during the induction phase, and that for most children behavior and attention problems rapidly return to baseline or improve.
Asunto(s)
Conducta Infantil/efectos de los fármacos , Cognición/efectos de los fármacos , Teofilina/farmacología , Trastorno por Déficit de Atención con Hiperactividad/psicología , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Teofilina/sangreRESUMEN
Several surface and volume rendering techniques are compared using nuclear medicine data including several new methods developed by the authors specifically for scintigraphic data. The techniques examined are summed projection, thresholded projection, threshold-based surface illumination, volumetric compositing, maximum-activity projection, sun-weighted maximum-activity projection, and variable attenuation. The advantages and disadvantages of each method are discussed in relation to the goals of three-dimensional display, which are defined herein. Selected images are shown to illustrate the usefulness of the methods.