RESUMEN
BACKGROUND AND PURPOSE: The loss of contrast on T1-weighted MR images at 3T may affect the detection of hyperintense punctate lesions indicative of periventricular leukomalacia in preterm neonates. The aim of the present study was to determine which 3T T1-weighted sequence identified the highest number of hyperintense punctate lesions and to explore the relationship between the number of hyperintense punctate lesions and clinical outcome. MATERIALS AND METHODS: The presence of hyperintense punctate lesions was retrospectively evaluated in 200 consecutive preterm neonates on 4 axial T1-weighted sequences: 3-mm inversion recovery and spin-echo and 1- and 3-mm reformatted 3D-fast-field echo. Statistically significant differences in the number of hyperintense punctate lesions were evaluated by using a linear mixed-model analysis. Logistic regression analysis was used to assess the relation between the number of hyperintense punctate lesions and neuromotor outcome at 3 months. RESULTS: Thirty-one neonates had at least 1 hyperintense punctate lesion indicative of periventricular leukomalacia in at least 1 of the 4 sequences. The 1-mm axial reformatted 3D-fast-field echo sequence identified the greatest number of hyperintense punctate lesions (P < .001). No statistically significant differences were found among the 3-mm T1-weighted sequences. The greater number of hyperintense punctate lesions detected by the 1-mm reformatted T1 3D-fast-field echo sequence in the central region of the brain was associated with a worse clinical outcome. CONCLUSIONS: At 3T, the 1-mm axial reformatted T1 3D-fast-field echo sequence identified the greatest number of hyperintense punctate lesions in the central region of preterm neonate brains, and this number was associated with neuromotor outcome.
Asunto(s)
Encéfalo/patología , Leucomalacia Periventricular/patología , Imagen por Resonancia Magnética/métodos , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Modelos Lineales , Masculino , Estudios RetrospectivosRESUMEN
Pseudoverrucous papules and nodules can be observed on skin surrounding urostomies and colostomies. These lesions appear to be uncommon, and sometimes can be misdiagnosed, even leading to surgical removal. We report the case of a 12-year-old boy whose lesions appeared in crops in an area subjected to urine leakage and spontaneously regressed in time. In this patient, anogenital warts had to be ruled out, but many skin diseases must be considered in the differential diagnosis of these misunderstood lesions. We stress the importance of a skin examination by a trained professional aware of these problems to avoid unnecessary investigations and treatments.
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Extrofia de la Vejiga/cirugía , Enfermedades Cutáneas Vesiculoampollosas/patología , Derivación Urinaria/efectos adversos , Biopsia con Aguja , Niño , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Masculino , Medición de Riesgo , Enfermedades Cutáneas Vesiculoampollosas/etiología , Enfermedades Cutáneas Vesiculoampollosas/cirugía , Incontinencia Urinaria/complicaciones , Incontinencia Urinaria/diagnósticoRESUMEN
We hypothesized that aging is associated with alterations in pharyngeal muscle structural and contractile properties. Sternohyoid and geniohyoid muscles from young (3-4 months) and old (20-21 months) Fischer 344 rats were compared with diaphragm muscle. The pharyngeal muscles had significantly lower proportions of slow oxidative (SO) fibers compared to the diaphragm, and the percentage of fast glycolytic (FG) fibers was significantly higher in the sternohyoid than in both the geniohyoid and the diaphragm. With senescence, there was a small but significant increase in the proportion of FG fibers and a corresponding reduction in the proportion of fast oxidative glycolytic (FOG) fibers in all three muscles. The sternohyoid muscle had significantly faster isometric contractile kinetics and lower fatigue indexes than the diaphragm. Aging was associated with significant worsening of sternohyoid endurance, but no significant alterations in sternohyoid twitch kinetics or diaphragm properties. These results indicate that in rats the pharyngeal dilator muscles have larger proportions of fast fibers, fast contractile kinetics and worse endurance than the diaphragm. Furthermore, aging was associated with a shift to a higher proportion of FG fibers with a concomitant reduction in proportion of FOG fibers, as well as a decline in pharyngeal muscle endurance.
Asunto(s)
Envejecimiento/fisiología , Diafragma/fisiología , Músculos Faríngeos/fisiología , Músculos Respiratorios/fisiología , Animales , Masculino , Fatiga Muscular/fisiología , Fibras Musculares de Contracción Rápida/fisiología , Ratas , Ratas Endogámicas F344 , Respiración/fisiologíaRESUMEN
Despite the wealth of information about the neural control of pharyngeal dilator muscles, little is known about their intrinsic physiological properties. In the present study the in situ isometric contractility and endurance of a pharyngeal dilator, the geniohyoid muscle, were compared with properties of the diaphragm in 12 anesthetized artificially ventilated cats. The contraction time (means +/- SE) of the geniohyoid (27 +/- 2 ms) was shorter than that of the diaphragm (36 +/- 3 ms; P less than 0.0005), as was the half-relaxation time (29 +/- 2 vs. 45 +/- 4 ms; P less than 0.002). The faster contraction and relaxation of the geniohyoid compared with the diaphragm were appropriately reflected in the shape of the force-frequency curves for the two muscles, with that of the geniohyoid located to the right of the diaphragm force-frequency curve. The endurance properties of the two muscles were assessed using repetitive stimulation at 40 Hz in trains lasting 0.33 s, with one train repeated every second. The ratio of force at the end of 2 min of repetitive stimulation to initial force was 0.67 +/- 0.06 for the geniohyoid and 0.15 +/- 0.03 for the diaphragm (P less than 0.00001). After the repetitive stimulation, the muscle force generated in response to a range of stimulus frequencies was reduced to a greater extent for the diaphragm than for the geniohyoid muscle. These results indicate that the geniohyoid muscle has a faster physiological profile than does the diaphragm yet is relatively resistant to fatigue when driven at high rates.
Asunto(s)
Diafragma/fisiología , Contracción Isométrica , Músculos del Cuello/fisiología , Animales , Gatos , Estimulación Eléctrica , Técnicas In Vitro , Cinética , Nervio Frénico/fisiologíaRESUMEN
The efficacy of josamycin in the treatment of inflammatory acne has been evaluated in 39 patients. Josamycin was orally administered to the patients as a single 500 mg daily dose for two months, but the patients with the most severe lesions received an initial treatment of 1 g for a maximum of 20 days. All subjects received josamycin in combination with other antiacne drugs mostly benzoyl peroxide ointment. The treatment induced a significant regression of the number and the severity of the lesions scored according to Plewig-Kligman's classification. At the end of the treatment a positive effect was observed for 92% of the subjects, independently of the variety and the degree of the severity of the disease. According to the patients' judgments josamycin was an effective treatment (92.3%) and more effective that the previously prescribed drugs (95%). Only 1 patient reported the occurrence of a side effect (mild gastric discomfort). Josamycin showed in this study to be an effective and safe drug for the treatment of inflammatory acne.