December 2007

Antigenic variation in pathogenic micro-organisms: similarities and differences

Antigenic variation is a process by which pathogenic micro-organisms escape the immune response of their mammalian hosts. By convergent evolution, protozoal, fungal and bacterial pathogens have developed similar genetic mechanisms for true antigenic variation. In this review article, the biology, the surface antigens and their encoding genes, and the molecular mechanisms of antigenic variation of the...

Author(s): Dietmar Steverding

December 2007

Immunoglobulin profile of some Nigerians with Schistosoma haematobium infection

The preliminary investigation revealed the prevalence of 138(46.9%) out of 294 volunteers screened for the ova of Schistosoma haematobium in their urine samples. Of these, 84(28.6%) had light infection (≤ 50 ova/10 ml urine), while 54(18.4%) had heavy infection (> 50 ova/10 ml urine). This difference was statistically significant at (χ2 = 6.52, p > 0.05). The mean immunoglobulin status were...

Author(s): O. P. G. Nmorsi, N. C. D. Ukwandu, C. Isaac, A. O. Egwunyenga and N. H. Olague

December 2007

Dielectric measurement of the resistance of Trichosporon cutaneum against toxic chemicals

Conditioning of cultures involves growing cells in the presence of increasing amounts of a toxic chemical. In order to investigate how conditioning affects a culture’s ability to resist new challenges, the resistance of Trichosporon cutaneum to various toxic chemicals, before and after conditioning to growth on phenol, was investigated by measuring the capacitance of cell suspensions at 0.4 MHz following...

Author(s): Filadia P. Tileva, Lyubov K. Yotova and Gerard H. Markx

December 2007

Hepatocellular carcinoma among patients diagnosed with and without hepatitis B surface antigenaemia in a Nigerian tertiary Hospital

Hepatitis B virus (HBV) infection has been reported as one of the aetiological factors for hepatocellular carcinoma (HCCA). This study reports the prevalence of HCCA in patients with and without HBV in Northeast Nigeria over a period of five years. A total of 114 patients consecutively diagnosed with HCCA and tested for Hepatitis B surface Antigen (HBsAg) at the University of Maiduguri Teaching Hospital (UMTH), between...

Author(s): B. B. Ajayi, H. A. Nggada and A. E. Moses

December 2007

Production of indole-3-acetic acid by Rhizobium isolates from Sesbania species

Rhizobium isolates from root (Sesbania procumbens) and stem nodules (S. rostrata and S. procumbens) of Sesbania species were shown to produce indole-3-acetic acid (IAA) in culture supplemented with L-tryptophan. Production of IAA was maximal after 72 h of incubation when the bacteria reached stationary phase of growth. The cultural requirements were optimized for maximum IAA production. The...

Author(s): M. Sridevi and K. V. Mallaiah