Predicting intellectual outcome among children treated with 35-40 Gy craniospinal irradiation for medulloblastoma

Fifty children diagnosed with medulloblastoma completed 188 psychological evaluations using the Wechsler Intelligence Scales for Children (D. Wechsler, 1974, 1991) over a 7-year study period following 35-40 Gy postoperative craniospinal irradiation. Random coefficient models were used to predict the trend in the children's intellectual performance as a function of time since diagnosis, with both patient and treatment variables as parameters of this function. A quadratic model demonstrated a delay prior to decline in performance for older patients, whereas the younger patients showed an immediate loss of performance with a plateau at approximately 6 years postdiagnosis. A steeper decline was found for those with higher baseline performance. Clinicians may use the proposed predictive model to identify those patients who are at risk of significant intellectual decline.     

XLMR genes: update 1992.

Up to now, we have identified 77 X-linked conditions in which mental retardation is the primary or a major component manifestation. These conditions were subdivided into 2 categories, designated respectively "X-linked mental retardation syndromes" and "Non-specific X-linked mental retardation". Forty genes have been regionally mapped onto the X chromosome. However, in several instances the data were derived from a single family and most lod scores were less than 3.0.     

Pulmonary diffusing capacity of the bullfrog (Rana catesbeiana)

Carbon monoxide diffusing capacity of the lungs (DLCO) was measured in bullfrogs, Rana catesbeiana (mean body weight 260 g) along with oxygen uptake, pulmonary perfusion and lung volume. The measurements were all performed by methods depending on mass-spectrometry. Pulmonary oxygen uptake, DLCO and perfusion all increased with body temperature. At 20 degrees C O2-uptake was 0.49 ml STPD . kg-1 . min-1 at rest and DLCO was 0.022 ml STPD . kg-1 . min-1 . Torr-1. At 30 degrees C the values for O2-uptake and DLCO approximately doubled. Lung volume was large (90 ml . kg-1) and independent of body temperature. Oxygen uptake and DLCO of the bullfrog were small compared to values for a similar-sized mammal but the ratios of DLCO to O2-uptake quite similar. Analysis of available data on DLCO and O2-uptake in ectotherms also suggests a close correlation between O2-uptake and DLCO.