No urobilinogens are present in the feces or urine of germfree rats. After contamination of germfree animals with feces from conventional animals the exgermfree rats produced urobilins to the same extent as conventional animals on the same diet. The negative urobilin test turned positive in germfree animals infected with a single Clostridium-like microorganism isolated from the intestinal conte...

The role of homology between donor and recipient DNAs in the protection of transfecting DNA against restriction by competent Bacillus subtilis R cells was studied under marker rescue conditions with modified helper phage. By comparing restriction under conditions of preinfection marker rescue and superinfection marker rescue, the significance of DNA homology during the initial stages of DNA pro...

When L cells are simultaneously infected with vaccinia virus and mengovirus, double interference in the replication of both viruses is observed. Superinfection of vaccinia virus-infected cells by mengovirus during the first 5 hr of infection reduces vaccinia virus yields to between 1 and 3% of controls. The yields of mengovirus are reduced to between 1 and 16% of controls, depending upon the ti...

This paper considers the epidemiology of two strains (I, J ) of a disease spreading through a population represented by a scale-free network. The epidemiological model is SIS and the two strains have different reproductive numbers. Superinfection means that strain I can infect individuals already infected with strain J , replacing the strain J infection. Individuals infected with strain I canno...

Fulminant hepatitis is a rare complication of acute hepatitis A virus (HAV) infection. We report three cases of fulminant hepatic failure with death due to HAV infection in patients with pre-existing chronic liver disease. Data from the literature also indicate a high case fatality rate during HAV superinfection in patients with chronic hepatitis B, particularly those with cirrhosis, and in pat...

Infection with influenza virus strongly predisposes an individual to bacterial superinfection, which is often the significant cause of morbidity and mortality during influenza epidemics. Little is known about the immunomodulating properties of the virus that lead to this phenomenon, but the effect of the viral components on the development of immune dendritic cells (DCs) may prove vital. In thi...

An 8.1-kb fragment of the temperate Myxococcus xanthus phage Mx8 genome, when cloned into a plasmid vector, permits site-specific integration of the plasmid and confers superinfection immunity. Sequence analysis of a 9.5-kb region of Mx8 DNA containing this fragment reveals 19 densely packed open reading frames, four of which have predicted products with known or suspected activities. The Mx8 i...