Susceptibility to actively-induced murine experimental allergic encephalomyelitis is not linked to genes of the T cell receptor or CD3 complexes

The role of the T cell receptor (TCR) in the genetic control of susceptibility to autoimmune demyelinating diseases remains shrouded in controversy. We have used the CXD2 series of recombinant inbred lines (RIL) and a (B10.S/DvTe x SJL/J) x B10.S/DvTe backcross (BC1) population to test for linkage between susceptibility to actively-induced EAE and the different TCR and CD3 loci. The two populations were inoculated for induction of EAE, phenotyped for both clinical and histological parameters of disease, and genotyped using markers flanking the loci of interest in the CXD2 RIL and an SJL/J allele-specific TCR V beta assay in the BC1 mice. Comparisons between the CXD2 strain distribution pattern (SDP) for disease and the SDPs for the chromosomal regions containing the TCR alpha, beta, gamma, delta, and CD3 delta, epsilon, gamma and zeta loci showed no linkage to these loci. Additional tests between EAE susceptibility and several other immunologically important loci for which the SDPs were known also showed no linkage to the minor lymphocyte-stimulating antigen gene Mlsl, Hc, the gene encoding complement component C5, Cd8a, or Cd5. Furthermore, our data from the BC1 mice demonstrate that the Tcrb locus segregates independent of disease and does not modulate disease severity. We conclude that while autoreactive TCRs are undoubtedly necessary for disease pathogenesis, the principle non-MHC-linked loci controlling susceptibility to murine EAE in BALB/c mice are not linked to any of the individual TCR-CD3 complex genes. Similarly, the major disease genes in the SJL/J mouse are not linked to TCR V beta. Our data cannot, however, preclude the possibility that TCR/CD3 alleles are involved in epigenetic phenomena or susceptibility in other mouse strains or animal systems.     

Free convective heat transfer to supercritical carbon dioxide

Experiments on free convective heat transfer from electrically heated platinum wires and a platinum strip to supercritical carbon dioxide were performed for a wide range of bulk conditions. It is shown that heat transfer can be predicted by a conventional Nusselt-type correlation if the dimensionless numbers are based on integrated thermophysical properties in order to account for large changes in these properties. The anomaly of thermal conductivity has to be considered. Agreement between the experimental results and the correlation is within 10% even for very thin wires when for those a correction factor is introduced.     

A difference in the composition of bronchial mucus between smokers and non-smokers

The effects of the duration of the overall compression cycle and of the duration of the maximum compressive force on tablet strength were studied using an instrumented rotary tablet press. Various direct compression fillers were evaluated. Increasing the overall compression cycle duration to 10 sec resulted in significantly greater tablet tensile strengths with microcrystalline cellulose and compressible starch fillers but not with lactose or compressible sugar. Increasing the duration of the maximum compressive force to 20 sec significantly increased the tensile strength in all cases, but microcrystalline cellulose and compressible starch tablets were affected more than lactose or sugar tablets. The maximum compressive force decayed with time for all fillers but at a greater rate with microcrystalline cellulose and compressible starch. This behavior was attributed to differences in the extent of plastic flow. The decay curves were analyzed using the Maxwell model.