Abnormal allometric size of vital body organs among sudden infant death syndrome victims.

Sudden infant death syndrome (SIDS) victims are difficult to describe physically because they seem outwardly indistinguishable in nearly all characteristics from infants (alive or dead) of comparable chronological age. Relative (allometric) size of vital organ and body weights has not been examined among SIDS victims. In the present study, autopsy organ and body weights for 152 SIDS deaths (1-12 months) were compared with the results of 115 controls that were trauma or illness-related death (0.25-12 months). A pattern of abnormal relative size in vital organs (brain, heart, liver, and kidney) was revealed. In allometric regressions, increase in the weights of the organs relative to total body weight among SIDS victims were approximately three times the increase among controls in the first year of life. This finding indicates a disturbance of normal patterns of vital organ size of SIDS victims that is of unknown etiology. Am. J. Hum. Biol. 12:382-387, 2000. Copyright 2000 Wiley-Liss, Inc.

Genes and regulatory sites of the "host-takeover module" in the terminal redundancy of Bacillus subtilis bacteriophage SPO1.

Early in infection of Bacillus subtilis by bacteriophage SPO1, the synthesis of most host-specific macromolecules is replaced by the corresponding phage-specific biosyntheses. It is believed that this subversion of the host biosynthetic machinery is accomplished primarily by a cluster of early genes in the SPO1 terminal redundancy. Here we analyze the nucleotide sequence of this 11.5-kb "host-takeover module," which appears to be designed for particularly efficient expression. Promoters, ribosome-binding sites, and codon usage statistics all show characteristics known to be associated with efficient function in B. subtilis. The promoters and ribosome-binding sites have additional conserved features which are not characteristic of their host counterparts and which may be important for competition with host genes for the cellular biosynthetic machinery. The module includes 24 genes, tightly packed into 12 operons driven by the previously identified early promoters PE1 to PE12. The genes are smaller than average, with half of them having fewer than 100 codons. Most of their inferred products show little similarity to known proteins, although zinc finger, trans-membrane, and RNA polymerase-binding domains were identified. Transcription-termination and RNase III cleavage sites were found at appropriate locations.