Exclusion from proximal 11q of a common gene with megaphenic effect on atopy

We have typed three markers on proximal 11q in 131 random families with three or more children studied for atopy. A summary map that includes the FCER1B candidate was constructed. Using a 2-locus disease model, we performed combined segregation and linkage analysis of three models, none of which suggested linkage. Nine marker loci on other chromosomes were also negative. In the regions swept by these 12 markers we cannot rule out a rare gene, perhaps of large effect, nor a common gene of small effect. However, a common gene of large effect is excluded. These results and alternative strategies are discussed in the perspective of inconsistent evidence for a major atopy gene.     

Modified Magnet Test for a Reversed Automatic Implantable Cardioverter Defibrillator

We present the case of a 55-year-old man with atrial septal defect and cardiomyopathy who underwent implantation of an automatic cardioverter defibrillator (AICD) for ventricular tachycardia resulting in collapse. This case demonstrates multiple unusual complications related to AICD, including rotation of the pulse generator unit about its long axis requiring a "left-handed" magnet test to determine the appropriate counts.     

Ultrastructural, Protein, and Lipid Changes in Liver Associated with Chlordecone Treatment of Mice

Pretreatment of mice with chlordecone (CD) reduced hepatic accumulationof a subsequent dose of [¹⁴C]CD without significantly changing[¹⁴C]CD biotransformation. To determine if CD-induced changesin hepatic [¹⁴C]CD accumulation were coincident with alteredcell composition, we examined the effects of CD on hepatic proteinand lipid content, on fatty acid profiles of liver and kidney,and on the ultrastructure of hepatocytes. SDS-polyacrylamidegel electrophoresis detected an apparent CD dose-related increasein a microsomal protein with a molecular weight of about 23kDa. Total liver or kidney lipid contents were not altered byCD but relative amounts of several hepatic fatty acids werechanged. CD caused marked hepatic mitochondrial swelling, increasedamounts of endoplasmic reticulum, apparently increased numbersof peroxisome-like structures, and decreased numbers of lipiddroplets in cytoplasm of hepatocytes. Numbers of lipid dropletswere not decreased in perisinusoidal fat storage cells. In addition,the numbers of cytoplasmic lipoprotein vesicles were apparentlyincreased in some hepatocytes. Overall these changes indicatedan increased hepatocyte secretory activity and suggested thatCD changed hepatocellular lipid transport, storage, and metabolismpathways.