BK and JC viruses in patients with systemic lupus erythematosus: prevalent and persistent BK viruria, sequence stability of the viral regulatory regions, and nondetectable viremia.

A role for polyomaviruses in the pathogenesis of systemic lupus erythematosus (SLE) has been suggested. BK virus (BKV) and JC virus (JCV) were demonstrated in single urine specimens from 7 (16%) of 44 and 5 (11%) of 44 patients with SLE and 0/88 and 18 (21%) of 88 matched healthy controls, respectively. During a 1-year follow-up study, episodes of polyomaviruria were detected in 16 (80%) of 20 patients, BKV in 13, and JCV in 3 patients. A group of 12 (60%) of 20 patients demonstrated persistent or recurrent polyomaviruria, BKV viruria (n=9), or JCV viruria (n=3) in 180 (70%) of 256 specimens. Polyomaviruria was not significantly associated with immunosuppressive therapy. The BKV and JCV isolates revealed predominantly stable archetypal regulatory regions over 3 years, indicating viral persistence rather than reinfection as a cause for urinary shedding. The demonstration of nondetectable viremia and stable archetypal BKV and JCV noncoding control regions during persistent viruria argue against the urinary tract as a focus for the creation of rearranged regulatory region variants.

Cellular Fatty Acid profiles of lactobacillus and lactococcus strains in relation to the oleic Acid content of the cultivation medium.

Cellular fatty acids of 10 strains of lactic acid bacteria were analyzed. The purpose of this work was to find lactic acid bacteria with high lactobacillic acid contents. The bacteria studied were unable to synthesize oleic acid. Some strains did not synthesize lactobacillic acid, although all were able to form dihydrosterculic acid. Twenty-one to thirty-four percent of the fatty acid content of Lactobacillus fermentum and L. buchneri was lactobacillic acid, and these species were chosen for future studies of environmental factors affecting cyclopropane fatty acid synthesis.

The effect of temperature on growth, indole alkaloid accumulation and lipid composition of Catharanthus roseus cell suspension cultures.

Cell suspension cultures of Catharanthus roseus were used to study the effect of temperature on plant cell lipids and indole alkaloid accumulation. Lowering the cultivation temperature increased the total fatty acid content per cell dry weight relative to that at higher temperatures, mainly because of increased accumulation of unsaturated C18 acids. In addition, an increase in the relative proportion of phosphatidylcholine and phosphatidylethanolamine was observed. Within individual lipids, the degree of unsaturation was increased and the mean fatty acid chain length decreased with reducing temperature. These changes may be interpreted as modifying the cell membrane fluidity to keep it optimal for growth and metabolism at each temperature. In spite of membrane modifications, the indole alkaloid content of the cells or the medium was not affected by temperature change.

The effect of temperature on hairy root cultures of Catharanthus roseus: Growth, indole alkaloid accumulation and membrane lipid composition.

Cultivation of Catharanthus roseus hairy root cultures at different temperatures was found to have an effect on growth rate and indole alkaloid content as well as lipid composition. When lowering the temperature, the roots responded by increasing the degree of unsaturation of cellular lipids, which was mainly due to an increased proportion of linolenic acid in the main lipid classes. The modifications in lipid composition were obviously necessary for the roots to retain the proper cell membrane fluidity at each temperature. Despite of changes in membrane lipids, no effect on the distribution of indole alkaloids between the roots and the medium could be detected. Instead, the level of alkaloid accumulation showed a clear increase with lowering temperature.