Effects of Neonatal Growth on Adult Blood Pressures of Borderline Hypertensive Rats

Abstract We conducted this study to test the hypothesis that there are long-term effects of litter-size manipulations during the preweaning period on growth and adult blood pressure of rats. Litter size of genetically homogeneous borderline hypertensive rats, which were produced by cross-mating male Wistar-Kyoto rats with female spontaneously hypertensive rats, was manipulated from 10 to 16 days of age. In addition, a subset of males and females was castrated within the first 30 hours of life. Body weights were measured at several preweaning and postweaning ages, and tail-cuff blood pressures were recorded at 90 days of age. Intact and castrated pups of both sexes that were reared in small (n=4) litters from 10 to 16 days of age gained nearly twice the weight of animals reared in large (n=9 to 12) litters during this period. Intact males from small litters had significantly higher adult blood pressures than those from large litters. These long-term effects remained even in groups matched for adult weight and length. Neonatal castration of males completely blocked the consequences of litter-size manipulation on adult blood pressure, suggesting either an organizational or activational role for androgens. Neither intact nor neonatally castrated females exhibited differences in adult blood pressure as a function of litter-size manipulation. </jats:p

Extensive Implant Reaction in Failed Subtalar Joint Arthroereisis: Report of Two Cases

Foreign body synovitis with extensive granulomatous giant cell reaction to refractile polyethelene debris is a complication of subtalar arthroereisis not previously reported. We present two cases whereby STA-peg implants were used to treat bilateral painful flexible flatfoot deformities in children. Two boys, presented at 7 and 10 years of age, 2 years after STA-peg procedures and tendo-Achilles lengthening for painful flatfeet. They each had minimal subtalar motion and pain at the sinus tarsi. Radiographs demonstrated surgical defects in the calcaneus with surrounding high signal on the magnetic resonance imaging (MRI) in the subchondral bone of the calcaneus and talus. Both patients failed conservative management and had their implants removed with good relief of their pain. Histology was submitted at the time of implant removal. We present the radiographic and pathologic findings seen in these two patients with failed subtalar arthroereisis due to extensive implant reaction. The pathologic process seen in these patients is a previously unreported complication of this procedure. We do not recommend arthroereisis in the treatment of painful flexible flatfoot in children