The impact of poverty on educational outcomes for children

Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings.     

Conduction studies in peripheral cat nerve using implanted electrodes: III. The effects of prolonged constriction on the distal nerve segment

Electrophysiological properties were monitored in detail in chronically constricted peripheral nerves by implanted, multicontact nerve cuff electrodes and correlated with morphometric histology in selected cases. The physiological and histological responses in nerve to a range of constricting cuffs of standard sizes were readily graded. The initial response to any significant constriction was a transient, focal conduction slowing or block at the constriction, followed by more protracted distal effects; the latter ranged from loss of excitability consistent with "dying-back" degeneration to reductions in conduction velocity consistent with histologically observed atrophy. Smaller myelinated fibers tended to have similar but less pronounced changes than larger diameter fibers. Recordings from ventral and dorsal roots showed that distal degeneration was more pronounced in motor than in sensory fibers of similar caliber. Electronmicroscopical measurements showed that basal laminas were relatively preserved around even the most atrophic and demyelinated axons. Perimeter measurements of the basal lamina could be used to estimate the diameter of the original nerve fiber.     

Contraceptive potential of a mifepristone-nomegestrol acetate sequential regimen in women

The effectiveness of a sequential regimen consisting of mifepristone, 10 mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for the next 13 days, for inhibiting ovulation and maintaining regular bleeding cycles was assessed in 10 surgically sterilized volunteers who were followed for one pretreatment and three treated cycles. Hormonal determinations in blood and urine, ovarian ultrasonography, bleeding records in all cycles and an endometrial biopsy taken on day 22-25 of the third treatment cycle were used to monitor the effects of treatment. During treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l) and six biphasic cycles were recorded. Nine follicular ruptures were detected echographically in these 30 treated cycles, five of which occurred in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA treatment. Echographic and endocrine features of ovulatory cycles were both present in only four treated cycles (13.3%). Development of a secretory endometrium was achieved in all cases, but it was always irregular. Regular withdrawal bleeding occurred in all subjects and no adverse reactions were recorded. The ovarian and endometrial effects of this regimen justify testing its contraceptive effectiveness in phase 2 clinical trials.      

Reliability of the acetabular teardrop as a landmark

Summary This study investigated the effect of tilt and observer reliability on radiographic measurements of the position of a prosthetic acetabular cup in seven dry bone pelves using the teardrop as a landmark. Coronal or sagittal tilt of more than five degrees was easily recognisable and there was effectively no observer variation in the measurements up to this limit. In addition, 90 out of 100 randomly selected antero-posterior pelvic radiographs from an outpatient department were not significantly rotated and 93 demonstrated a clearly defined teardrop. Measurements about the teardrop on routine radiographs are therefore sufficiently accurate to allow assessment of prosthetic position.

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La valeur du sourcil cotyloidien comme repère d'analyse radiologique

Résumé Cette étude, conduite sur 7 bassins secs, apprécie l'effet de l'inclinaison du bassin sur la qualité de l'analyse radiographique de la position d'une cupule prothétique de hanche en utilisant le sourcil cotyloïdien comme repère. Une inclinaison du bassin dans les plans coronal et sagittal est aisément détectable et il n'existe pas de variation d'analyse entre les différents observateurs en dessous de 5° d'inclinaison. De plus, sur 100 radiographies antéro-postérieures de bassin choisies au hasard dans les dossiers de consultation, 90 avaient été réalisées sans incidence particulièrement adaptée et l'on pouvait repérer facilement le sourcil sur 93% d'entre elles. Les mesures faites sur des radios de routine sont donc suffisamment précises pour permettre l'évaluation de la position d'une prothèse à partir du sourcil cotyloïdien.

     

Chronic portal venous hypertension. The effect on liver blood flow and liver function and the development of esophageal varices

Portal venous hypertension was induced in G?ttingen minipigs by banding the portal vein. The pigs were checked repeatedly during the following 24 weeks. Portal pressure increased immediately on banding, from 8.4 +/- 0.7 mm Hg to 19.4 +/- 0.7 mm Hg, and remained constant throughout the observation period. Within 5 weeks all pigs developed esophageal varices, as demonstrated by portal angiography and endoscopy. The experimentally induced portal hypertension was accompanied by a 65% decrease in hepatic blood flow, most probably caused by almost complete shunting of portal venous blood. The hepatic arterial flow appeared to be within normal limits and sufficient to cover the oxygen demand of the liver; to judge from the splanchnic elimination rate of galactose, the hemodynamic changes did not affect the functional capacity of the liver.