This study examined how the monoblast-like human histiocytic lymphoma cell line U937 can be induced by phorbol 12-myristrate 13-acetate (PMA) to undergo differentiation. In order to study the mechanism of action of CSF-1, a CSF-1 receptor gene (c-fms) was transfected into U937 cells. Exogenous CSF-1 treatment induced an autocrine response in this CSF-1 was determined and all events were shown to be time dependent. CSF-1 stimulation also enhanced proto-oncogene c-jun and c-myc gene expression. Complementary DNA coding for Jun or Fos was introduced into U937 cells by transfection. The transfection did not generate a high level of CSF-1 gene expression which suggests that Fos and Jun alone are insufficient to induce CSF-1 synthesis.

No description available.

No description available.

Abstract The genetic diversity and identification of slow- and fast- growing soybean root nodule bacterial isolates from different agro-climatic regions in Mpumalanga, Limpopo and Gauteng Provinces of South Africa were evaluated. The 16S-rDNA-RFLP analysis of 100 rhizobial isolates and eight reference type strains placed the isolates into six major clusters, and revealed their site-dependent genomic diversity. Sequence analysis of single and concatenated housekeeping genes (atpD, glnII and gyrB), as well as the symbiotic gene nifH captured a considerably higher level of genetic diversity and indicated the dominance of Bradyrhizobium diazoefficiens and Bradyrhizobium japonicum in Mpumalanga, Limpopo and Gauteng Provinces. Gene sequence similarities of isolates with type strains of Bradyrhizobium ranged from 97.3 to 100% for the 16S rDNA, and 83.4 to 100% for the housekeeping genes. The glnII gene phylogeny showed discordance with the other genes, suggesting lateral gene transfer or recombination events. Concatenated gene sequence analysis showed that most of the isolates did not align with known type strains and might represent new species from South Africa. This underscores the high genetic variability associated with soybean Bradyrhizobium in South African soils, and the presence of an important reservoir of novel soybean-nodulating bradyrhizobia in the country. In this study, the grouping of isolates was influenced by site origin, with Group I isolates originating from Limpopo Province and Group II and III from Mpumlanga Province in the 16S rDNA-RFLP analysis.

MA, Faculty of Arts,University of the Witwatersrand, 1953

Fecal specimens from 130 different mares were collected from an endemic farm for 2 consecutive years at 4 different times pre- and post-foaling (41 mares contributed data in both years). A modified NANAT agar medium was used to quantitatively culture 1-g aliquots of the mare feces without inhibition of growth of Rhodococcus equi. Once the R. equi in the mare feces were quantified and the total concentrations of R. equi determined, a colony immunoblot procedure was performed to detect the presence of the virulence-associated protein antigen on the isolates. This allowed for the proportion and concentration of virulent R. equi to be determined. Foals that were found to have ultrasonographic evidence of peripheral pulmonary abscessation or consolidation underwent aseptic trans-cutaneous tracheobronchial aspiration. Positive results of TBA were used to categorize foals as affected with R. equi pneumonia. R. equi pneumonia developed in 31% of the foals. Shedding of virulent R. equi was observed in at least 1 sampling period for every mare examined, and >33% were culture-positive during all sampling periods. However, significant differences were not observed in either the fecal concentrations of total or virulent R. equi from dams of affected foals compared to dams of unaffected foals. No significant temporal changes in the fecal concentrations of R. equi were observed. It was concluded that dams of affected foals do not shed more R. equi in feces than do dams of unaffected foals, indicating that heavier shedding by particular mares does not explain infection in their foals. However, the finding that virulent R. equi were excreted in the feces of all sampled mares indicates that mares are likely an important source of R. equi for their surrounding environment.

Fecal specimens from 130 different mares were collected from an endemic farm for 2 consecutive years at 4 different times pre- and post-foaling (41 mares contributed data in both years). A modified NANAT agar medium was used to quantitatively culture 1-g aliquots of the mare feces without inhibition of growth of Rhodococcus equi. Once the R. equi in the mare feces were quantified and the total concentrations of R. equi determined, a colony immunoblot procedure was performed to detect the presence of the virulence-associated protein antigen on the isolates. This allowed for the proportion and concentration of virulent R. equi to be determined. Foals that were found to have ultrasonographic evidence of peripheral pulmonary abscessation or consolidation underwent aseptic trans-cutaneous tracheobronchial aspiration. Positive results of TBA were used to categorize foals as affected with R. equi pneumonia. R. equi pneumonia developed in 31% of the foals. Shedding of virulent R. equi was observed in at least 1 sampling period for every mare examined, and >33% were culture-positive during all sampling periods. However, significant differences were not observed in either the fecal concentrations of total or virulent R. equi from dams of affected foals compared to dams of unaffected foals. No significant temporal changes in the fecal concentrations of R. equi were observed. It was concluded that dams of affected foals do not shed more R. equi in feces than do dams of unaffected foals, indicating that heavier shedding by particular mares does not explain infection in their foals. However, the finding that virulent R. equi were excreted in the feces of all sampled mares indicates that mares are likely an important source of R. equi for their surrounding environment.

“Luke Tower sat in front of his laptop, staring first at the unyielding, blinking cursor and then to the bright red “8:05” displayed on his alarm clock. He always made sure to hide the taskbar on his screen, so that time was never an issue, but somehow it always managed to find him in one way or the other.” In many ways, this opening passage sums up Luke’s story. His life is almost a constant state of battle, whether it’s against writer’s block, time, or his unrealized feelings. Through the following story, Luke’s character takes a journey, searching for clues to the mystery of the colony of Roanoake, that may also end up leading him to find other things in his own life, some of which he wasn’t even aware were lost. / Access to thesis permanently restricted to Ball State community only / Department of English

Includes copies of articles co-authored by the author during the preparation of this thesis, in back pocket. / Errata attached to back flyleaf. / Includes bibliographical references (leaves 127-139). / 139 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The results presented lend further evidence to previous work suggesting that cold shock domain factors function to repress granulocyte macrophage-colony stimulating factor transcription via DNA binding to single stranded regions across the proximal promoter. / Thesis (Ph.D.)--Adelaide University, Dept. of Medicine, 2001

Diss. (sammanfattning) Stockholm : Karol. inst., 2001. / Härtill 5 uppsatser.