Heartworm disease in cats has been attributed to immature adult heartworms reaching the pulmonary arteries approximately 2.5-4 months post infection and the presence of mature adult worms in the cardiopulmonary system approximately 6 months after infection. The arrival and death of immature heartworms causes significant lung pathology, a condition referred to as heartworm-associated respiratory disease (HARD). To evaluate the humoral immune response to Dirofilaria immitis, 12 cats were each infected by subcutaneous injection of 100 third-stage larvae. Post-infection serum samples were collected weekly for 4 weeks, every other week for the following 4 weeks, then monthly to day 270 for evaluation of antibodies to D. immitis recombinant antigens HWAg-1 and HWAg-2 and circulating heartworm antigen (HWAg) using the PetChek (R) HTWM PF Test Kit (IDEXX Laboratories). Necropsies were performed 278-299 days post infection for collection of adult worms. Eleven cats were HWAg1 antibody-positive 68 days post-infection, and the remaining cat became positive by day 140. Eleven cats were positive for HWAg-2 antibody 42-84 days post infection; all 11 remained HWAg-2 antibodypositive through day 270. Circulating HWAg was detected in 10 cats, 2 by day 140 and 8 others by day 168. The 2 antigen-negative cats had no adult worms at necropsy. This study demonstrates that decomposition of immature adult heartworms can result in detectible levels of circulating antigen prior to sexual maturation. In this experimental model, D. immitis antigen was detectable in cats at time points (days 140 and 168) associated with HARD from dying immature adult heartworms.

BACKGROUND:The outcome of treatment for advanced hepatoblastoma has recently improved after the introduction of preoperative or pre- and postoperative cisplatin-containing chemotherapy combined with complete surgical excision. The role of liver transplantation in a population of patients who have received this regimen has not been clearly defined.METHODS:Orthotopic liver transplantation (OLT) was performed in 13 children, aged 5 months to 11 years (median 27 months), who were assessed with unresectable hepatoblastoma, and whose pretreatment extent-of-disease was based on radiologic findings of group III (n=11) and group IV (n=2). One child with a multifocal tumor showed pulmonary metastases at presentation, but, according to radiologic studies, the deposits resolved with chemotherapy before liver transplantation. One other child showed exophytic extension of the primary tumor infiltrating the porta hepatis and body of the pancreas. All 13 patients received preoperative chemotherapy to reduce the size of the primary tumor(s) and to treat metastatic spread.RESULTS:Twelve children underwent elective OLT; all are alive and show normal graft function at a mean follow-up of 33 months (range 1-108). One child shows evidence of recurrent disease in the form of pulmonary metastases. One child underwent emergency OLT for acute liver failure after (incomplete) extended right hepatectomy and died from respiratory failure, with no evidence of recurrent tumor 3 weeks posttransplant.CONCLUSIONS:Liver transplantation is an effective treatment for unresectable unifocal or multifocal hepatoblastoma confined to the liver. A multidisciplinary approach to the management of hepatoblastoma, with thoughtful collaboration between pediatric oncologists, hepatologists, and liver surgeons, is essential.

The goal of this paper is to draw attention to the long lasting effect of education on economic outcomes. We use the relationship between education and two routes to early retirement – the receipt of Social Security Disability Insurance (DI) and the early claiming of Social Security retirement benefits – to illustrate the long-lasting influence of education. We find that for both men and women with less than a high school degree the median DI participation rate is 6.6 times the participation rate for those with a college degree or more. Similarly, men and women with less than a high school education are over 25 percentage points more likely to claim Social Security benefits early than those with a college degree or more. We focus on four critical “pathways” through which education may indirectly influence early retirement – health, employment, earnings, and the accumulation of assets. We find that for women health is the dominant pathway through which education influences DI participation. For men, the health, earnings, and wealth pathways are of roughly equal magnitude. For both men and women the principal channel through which education influences early Social Security claiming decisions is the earnings pathway. We also consider the direct effect of education that does not operate through these pathways. The direct effect of education is much greater for early claiming of Social Security benefits than for DI participation, accounting for 72% of the effect of education for men and 67% for women. For women the direct effect of education on DI participation is not statistically significant, suggesting that the total effect may be through the four pathways.