Paul Tolstoshev

Cells, collagen and idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a usually fatal disorder of lung with clearly defined clinical, roentgenographic, physiologic, morphologic, scintigraphic and bronchoalveolar lavage features. Current concepts of the pathogenesis of this disorder suggest a central role for a chronic alveolitis in causing changes in parenchymal cell populations and derangements in interstitial collagen. Of the many inflammatory and immune effector cells comprising the alveolitis of IPF, it is likely that the neutrophil is the most important mediator of parenchymal damage. To follow the status of lung neutrophils in patients with this disease, two methods have been utilized. Both gallium-67 scanning and bronchoalveolar lavage quantitate the extent of the alveolitis and can be used to stage and follow these patients. The treatment of IPF remains controversial, but it is likely that corticosteroids reduce the alveolitis and prolong the lifespan of these patients.

Procollagen α2 mRNA is significantly different from procollagen α1(I) mRNA in size or secondary structure

Abstract The fractionation of fetal calf tendon messenger RNA in 85 percent formamide sucrose gradients shows a separation of the mRNAs coding for pro α1(I) and pro α2 chains of type I collagen. This difference in sedimentation in denaturing gradients suggests that pro α2 mRNA is approxmately 1000 bases shorter than pro α1(I) mRNA. However, such a size difference is significantly greater than would be predicted from consideration of the size of the polypeptide chains coded for by these mRNAs, and thus, residual secondary structure in the mRNAs may contribute to these apparent size differences.

The divergence between human and baboon globin genes.

Complementary DNA (cDNA) was prepared with viral RNA-directed DNA polymerase from purified baboon globin messenger RNA (mRNA). Homologous and heterologous hybrids between human and baboon mRNAs and cDNAs were compared for extent of hybridisation and thermal stability. Higher mRNA inputs to the hybridizations were required to reach saturation in the heterologous cases. The melting temperature of the heterologous hybrid was 5 degrees C lower than the homologous hybrid. Between these two primates, divergence has occurred in the globin gene to a smaller extent than that possible from third position changes in the coding sequences of the divergence of total DNA. Globin cDNA prepared from baboon will not in general be useful as a probe for human globin mRNA or human globin gene sequences.