ABSTRACT
Gastric biopsy samples obtained from 14 patients with upper abdominal pain, clinically diagnosed as acid peptic disease, were analysed for the presence of Helicobacter pylori (H. pylori) by Polymerase Chain Reaction (PCR) using partially (template A) and completely purified DNA (template B). Antigen specific primer was used to analyse the sample by PCR method. The presence of H. pylori in the samples was confirmed by running a positive control. The presence of H. pylori was also detected by urease method using standard protocol. Among the 14 samples studied, 8 showed the presence of H. pylori with both templates A and B. Among these 8 samples only 3 showed positive for the presence of H. pylori with urease method. The present work discusses the results obtained in the detection of H. pylori in template A and B by PCR method.
ABSTRACT
Whether natural radiation can be a conditioning factor for the growth and survival of a living organism was investigated using diploid yeast S. cerevisiae D7. Yeast cells were conditioned by growing them continuously for at least 100 generation in 3 different radiation background such as i) ambient radiation (1.1 mSv/y), ii) sub-ambient radiation (0.44 mSv/y, within a shielded chamber) and iii) an elevated background radiation (88 and 880 mSv/y in a gamma-field). At the end, the cells were challenged with 60Co gamma, 100 Gy and the viable fractions were determined. Conditioning the cells in 880 mSv/y and in ambient radiation, enabled the cells to reduce the deleterious effect of the challenging dose significantly (P < 0.05) compared to that of sub-ambient radiation. The cellular viability of yeast cultures seems to be influenced by the prevailing radiation background, apart from starvation. Comparatively, a rapid decline in viability was noticed when the cultures were incubated for 60 days in the shielded chamber. The results indicate that some amount of radiation equivalent to background level or little above is needed to confer fitness in biological systems against stress factors, including radiation. The adaptive dose for the diploid yeast was also determined by single exposure. The priming dose ranged from 0.01 to 1.2 Gy. An adaptive dose of 0.25 or 0.4 Gy, almost nullified the deleterious effect of the challenging dose. The adaptive response may have a greater role in the field of cancer therapy and in radiation risk assessment. Understanding the response of an organism at different radiation-background will be helpful for successful space management.