Basis of pulmonary toxicity associated with cationic lipid-mediated gene transfer to the mammalian lung

Studies have indicated that although abundant levels of transgene expression could be achieved in the lungs of mice instilled with cationic lipid:pDNA complexes, the efficiency of gene transfer is low. As a consequence, a relatively large amount of the complex will need to be administered to the human lungs to achieve therapeutic efficacy for indications such as cystic fibrosis. Because all cationic lipids exhibit some level of cytotoxicity in vitro, we assessed the safety profile of one such cationic lipid, GL-67, following administration into the lungs of BALB/c mice. Dose-dependent pulmonary inflammation was observed that was characterized by infiltrates of neutrophils, and, to a lesser extent, macrophages and lymphocytes. The lesions in the lung were multifocal in nature and were manifested primarily at the junction of the terminal bronchioles and alveolar ducts. The degree of inflammation abated with time and there were no apparent permanent fibrotic lesions, even in animals that were treated at the highest doses. Analysis of the individual components of the complex revealed that the pulmonary inflammation was primarily cationic lipid-mediated with a minor contribution from the neutral co-lipid DOPE. Associated with the lesions in the lungs were elevated levels of the pro-inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) that peaked at days 1-2 post-instillation but resolved to normal limits by day 14. Total cell counts, primarily of neutrophils, were also significantly elevated in the bronchoalveolar lavage fluids of GL-67:pDNA-treated mice between days 1 and 3 but returned to normal limits by day 14. No specific immune responses were detected against the cationic lipid or plasmid DNA in mice that had been either instilled or immunized with the individual components or complex, nor was there any evidence of complement activation. These studies indicate that a significant improvement in the potency of cationic lipid:pDNA formulations is desirable to minimize the toxicity associated with cationic lipids.     

Household family structure and children's aggressive behavior: a longitudinal study of urban elementary school children

The relationship between contemporary household family structures at fourth-grade and sixth-grade parent- and teacher-rated aggression was examined in an epidemiologically defined population of urban school children. The relationship between family structure and aggression varied by child gender and by parent and teacher ratings in the home and school, respectively. After taking into account family income, urban area, and fourth-grade aggressive behavior, boys in both mother-father and mother-male partner families were significantly less likely than boys in mother-alone families to be rated as aggressive by teachers. No significant relations between family structure and teacher- or parent-rated aggression were found for girls.     

The effect of early surgical excision and homografting on survival of burned rats and of intraperitoneally-infected burned rats

The effects of early and delayed surgical excision and skin homografting on survival in burned, uninfected rats and in burned rats infected with Pseudomonas aeruginosa, intraperitoneally, has been studied. The survival rate in animals treated with surgical excision and no coverage was significantly worse than in the animals who were simply burned. Immediate excision of the burn wound followed by prompt coverage with skin homografts resulted in decrease in the mortality rate from subsequent intraperitoneal infection of Pseudomonas. The beneficial effects of early surgical excisions and immediate skin homograft coverage were also achieved when formalin-fixed skin homografts were used.     

Effect of a stimulating factor formed by Aspergillus wentii on exoprotease biosynthesis by a culture of Aspergillus kanagawaensis

The object of this work was to study the composition of proteases synthesized by an active culture of Aspergillus kanagawaensis (I) as well as that in the presence of a cultural broth of Asp. wentii (II) which did not produce exoproteases. Enzyme complexes I and II are similar in qualitative composition but complex II has a higher proteolytic activity. The preparation containing the stimulating factor produced by Asp. wentii has been separated by gel filtration and ultrafiltration. Biosynthesis of exoproteases is stimulated by low molecular weight fractions of the cultural broth of Asp. wentii.