RESUMEN
The value of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for the identification of bacteria and yeasts is well documented in the literature. Its utility for the identification of mycobacteria and Nocardia spp. has also been reported in a limited scope. In this work, we report the specificity of MALDI-TOF MS for the identification of 162 Mycobacterium species and subspecies, 53 Nocardia species, and 13 genera (totaling 43 species) of other aerobic actinomycetes using both the MALDI-TOF MS manufacturer's supplied database(s) and a custom database generated in our laboratory. The performance of a simplified processing and extraction procedure was also evaluated, and, similar to the results in an earlier literature report, our viability studies confirmed the ability of this process to inactivate Mycobacterium tuberculosis prior to analysis. Following library construction and the specificity study, the performance of MALDI-TOF MS was directly compared with that of 16S rRNA gene sequencing for the evaluation of 297 mycobacteria isolates, 148 Nocardia species isolates, and 61 other aerobic actinomycetes isolates under routine clinical laboratory working conditions over a 6-month period. MALDI-TOF MS is a valuable tool for the identification of these groups of organisms. Limitations in the databases and in the ability of MALDI-TOF MS to rapidly identify slowly growing mycobacteria are discussed.
Asunto(s)
Actinobacteria/clasificación , Técnicas de Tipificación Bacteriana , Mycobacterium/clasificación , Nocardia/clasificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Actinobacteria/genética , Humanos , Mycobacterium/genética , Mycobacterium tuberculosis/clasificación , Nocardia/genética , ARN Ribosómico 16S/genética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/normasRESUMEN
We report on two sib fetuses with radiological and morphological findings similar to those of the recently described lethal skeletal dysplasia termed Pacman dysplasia (McKusick, 167220, Am J Med Genet 1993, 45:558-561). The first fetus, a male, was electively terminated after a routine ultrasound study at 20 weeks showed short-limb dwarfism. The second fetus, a female sib, was also electively terminated after similar, abnormal ultrasound findings were noted at 16 weeks of gestation. Similar to Pacman dysplasia, the radiographic appearance was characterized by under-mineralized bone, stippling, rhizomelic and mesomelic shortness, platyspondyly, and a short, broad pelvis. The metaphyses were dense, but the diaphyseal cortices were thin with undermodeled long bones, and there was a deficient trabecular pattern suggesting marrow replacement. Chondro-osseous structure was characterized by deficient trabecular bone formation, a fibrous marrow, and numerous, large, multinucleated osteoclasts lining the endosteal surfaces of the metaphyseal bone. The occurrence of this dysplasia in sibs of differing sex suggests autosomal recessive inheritance.
Asunto(s)
Feto/anomalías , Osteocondrodisplasias/genética , Femenino , Feto/diagnóstico por imagen , Humanos , Masculino , Osteocondrodisplasias/patología , Osteoclastos/patología , RadiografíaRESUMEN
We present a retrospective study on the incidence of visually impairing secondary posterior capsule opacification following fixation of an intraocular lens implant either in the ciliary sulcus or the capsular bag. One hundred patients in each group were evaluated 3 1/2 to 3 3/4 years following uncomplicated extracapsular cataract extraction. Only implants with convex-plane optics and forward angulated haptics were used. The incidence of capsular opacification was 20% in eyes with sulcus fixation as opposed to 14% for those with capsular bag fixation. This difference was statistically not significant. The difference in average postoperative interval until development of the secondary cataract (21 months for sulcus, 28 months for capsular bag fixation) or the age of patients with capsular opacification was statistically not significant either. However, it was noted that of the younger patients, between 40 and 50 years at the time of operation, only those with sulcus fixated implants developed secondary cataracts.
Asunto(s)
Extracción de Catarata , Catarata/epidemiología , Lentes Intraoculares , Complicaciones Posoperatorias/epidemiología , Técnicas de Sutura , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Alemania/epidemiología , Humanos , Incidencia , Terapia por Láser , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugíaRESUMEN
We report the case of a 25 year old caucasian female who was presented to our clinic with a four year history of recurrent vitreous hemorrhages, myelinated retinal nerve fibers and ipsilateral anisometropic myopia, astigmatism and amblyopia of her right eye. On fluorescein angiography small, postcapillary venous malformations in the area of myelinization were diagnosed. Vascular anomalies within regions of myelinated retinal nerve fibers have not been described so far. Even if actual leakage itself from the anomalous vessels could not be documented, vitreous hemorrhaging did not recur after successful lasercoagulation and obliteration of the vascular anomalies.
Asunto(s)
Malformaciones Arteriovenosas/diagnóstico , Fibras Nerviosas Mielínicas , Vena Retiniana/anomalías , Hemorragia Vítrea/diagnóstico , Adulto , Malformaciones Arteriovenosas/cirugía , Femenino , Angiografía con Fluoresceína , Humanos , Fotocoagulación , Fibras Nerviosas Mielínicas/fisiología , Agudeza Visual/fisiología , Campos Visuales/fisiología , Hemorragia Vítrea/cirugíaRESUMEN
In order to study the potential use of ultrasound as a noninvasive system for altering corneal curvature, we used high-density focused ultrasound at a frequency of 4.8 MHz and 7.9 MHz to produce corneal lesions in the rabbit eye. Intensity and duration threshold exposure conditions were determined for the production of minimally visible lesions. Threshold lesions were initially apparent as discrete white opacities resulting from stromal edema and disruption. Light and scanning electron microscopy of higher-energy, suprathreshold lesions revealed more extensive disruption, including the formation of a superficial stromal depression and a larger zone of edema and disorganization surrounding each lesion. Posterior stromal lamellae, endothelium, and Descemet's membrane were intact. Healing and reepithelialization resulted in a smooth corneal surface with no residual opacification. Threshold determinations predict safe exposure levels to the cornea during insonification of other ocular structures. Selective heating of the peripheral cornea using focused ultrasound may be a useful technique for correcting astigmatism.
Asunto(s)
Córnea , Ultrasonido , Animales , Córnea/ultraestructura , Lesiones de la Cornea , Sustancia Propia/lesiones , Sustancia Propia/ultraestructura , Umbral Diferencial , Epitelio , Calor , Microscopía Electrónica de Rastreo , Conejos , Ultrasonido/efectos adversos , Cicatrización de HeridasRESUMEN
High-intensity focused ultrasound was used to insonify simulated vitreous hemorrhages in two in vitro models and one in vivo animal model. Histopathologic evaluation of the treatment effect was performed with light and electron microscopy. Ultrasonic parameters resulting in histopathologically proven disruption and hemolysis of intravitreal blood were investigated. Most important in obtaining this effect were the temporal average acoustic power and pulse repetition rate of the applied ultrasonic beam. Accurate positioning of the therapeutic beam and visualization of internal spatio-temporal response patterns in the blood during insonification were monitored via simultaneous diagnostic B-mode imaging. Results suggested that high-intensity focused ultrasound might facilitate the two major mechanisms involved in the natural resorption process of vitreous hemorrhages namely hemolysis and surface-dependent phagocytosis.
Asunto(s)
Terapia por Ultrasonido , Hemorragia Vítrea/terapia , Animales , Bovinos , Hemólisis , Técnicas In Vitro , ConejosRESUMEN
Commercially available tissue glue was injected subretinally under mechanically induced retinal detachments in rabbit eyes resulting in chorioretinal adhesions at the injection site. After serial enucleation all eyes underwent histologic evaluation. Results were encouraging, but pooled fibrinogen is not acceptable for human use. A substitute for the pooled fibrinogen fraction, an adhesive using autologous plasma was prepared and studied after subretinal and intravitreal injection into rabbit and pig eyes. Postoperative clinical follow-up was one year for the rabbit eyes and one month for the pig eyes, after which all globes were enucleated. Histopathologic evaluation demonstrated circumscribed chorioretinal adhesions at the injection site. The autologous bioadhesive was applied as an adjunct in vitreoretinal surgery over macular holes and large retinal tears. As it is relatively short acting (ie, 4-6 days), it may be considered as a possible addition to existing techniques, facilitating difficult surgical procedures.
Asunto(s)
Aprotinina/uso terapéutico , Factor XIII/uso terapéutico , Fibrinógeno/uso terapéutico , Desprendimiento de Retina/cirugía , Trombina/uso terapéutico , Adhesivos Tisulares/uso terapéutico , Adulto , Anciano , Animales , Combinación de Medicamentos/uso terapéutico , Femenino , Adhesivo de Tejido de Fibrina , Estudios de Seguimiento , Humanos , Inyecciones , Masculino , Persona de Mediana Edad , Conejos , Desprendimiento de Retina/patología , Perforaciones de la Retina/patología , Perforaciones de la Retina/cirugía , Porcinos , Agudeza Visual , Cuerpo VítreoRESUMEN
Thirty-five consecutive cases of perforating ocular injuries with retained intraocular foreign body (IOFB) are examined in this retrospective study. Of the 35 cases with injuries, 30 (86%) were due to metallic foreign bodies. Of these, 25 (83%) involved foreign bodies of ferromagnetic origin. Magnetic extraction in combination with pars plana vitrectomy (or when possible, magnetic extraction alone) was successfully used to remove these foreign bodies. Even in cases where posterior vitrectomy is indicated, magnetic extraction allows good control of the foreign body during removal minimizing surgical trauma and the subsequent postoperative inflammatory response.