UreC PCR based diagnosis of Helicobacter pylori infection and detection of cag A gene in gastric biopsies.

Polymerase chain reaction assay using ureC gene specific primers for the detection of Helicobacter pylori in gastric biopsy specimens from 116 dyspeptic patients was compared with other routine invasive diagnostic methods (culture, rapid urease test [RUT] and histology). In parallel, gastric biospy specimens from 54 patients and their corresponding Helicobacter pylori isolates were subjected to PCR with cagA targeting primers using standard protocols. Helicobacter pylori were detected in 53%, 43%, 48% and 50% of patients by PCR, RUT, culture and histological examination respectively. Based on histology and culture positive and at least three test positive result, 44 (37%), 46 (39%) and 26 (22%), and 56 (48%), 52 (44%) and 8 (6%) patients were classified as Helicobacter pylori positive, negative and indeterminate respectively. The sensitivity and specificity of PCR assay was the highest-95% and 100% when compared with both culture and histology positive, and at least any three positive results respectively. The result of cagA positivity in 54 gastric biopsy specimens and their corresponding Helicobacter pylori isolates were identical; 18 of 20 (90%) duodenal ulcer patients and 23 of 28 (82%) patients with chronic gastritis and 2 (40%) of 5 patients with portal hypertension and one gastric biopsy specimens from gastric cancer patients were found to be cagA positive. PCR-based method to detect Helicobacter pylori and the virulence gene cag A directly from gastric biopsy specimens appears to be promising and can curtail the lengthy process of culture-based approaches. The procedure proved to be rapid and reliable and could be utilized for diagnostic purposes.

Comparison of various conventional methods with a polymerase chain reaction assay for detecting methicillin-resistant & susceptible Staphylococcus aureus strains.

BACKGROUND & OBJECTIVES: Methicillin-resistant Staphylococcus aureus (MRSA), a major nosocomial pathogen world-wide, is often difficult to detect due to the heterogeneous nature of expression of oxacillin resistance. In the present study, various conventional methods were compared with polymerase chain reaction on 106 clinical isolates of Staph. aureus for detection of oxacillin resistance. METHODS: A total of 106 clinical isolates of Staph. aureus were tested for oxacillin resistance by disc diffusion, screen agar plates (3 micrograms and 6 micrograms/ml of oxacillin), oxacillin broth (3 micrograms/ml) and mecA based PCR. RESULTS: PCR detected mecA gene amplified product of 604 bp in 57 strains. Disc diffusion failed to detect 7 mecA positive strains but identified 5 mecA negative strains as oxacillin resistant. Screen agar 3 micrograms, screen agar 6 micrograms and oxacillin broth 3 micrograms detected 55, 53 and 55 respectively of the 57 mecA positive strains; however, they also falsely identified 5, 3 and 3 strains of mecA negative strains respectively as oxacillin resistant. The sensitivity, specificity and accuracy of disc diffusion, 3 micrograms screen agar, 6 micrograms screen agar and 3 micrograms oxacillin broth against PCR as gold standard were as follows: 87.7, 89.9 and 88.7 per cent; 96.5, 89.8 and 93.4 per cent; 93.0, 93.9 and 93.4 per cent; 96.5, 93.9 and 95.3 per cent respectively. INTERPRETATION & CONCLUSIONS: The present study demonstrated that disc diffusion test was least reliable and 3 micrograms broth had the highest sensitivity and specificity when compared with PCR for detection of oxacillin resistance. Because of variations among the methods, a combination of tests should be used for the accurate detection of MRSA till new guidelines by an appropriate body are formulated.

A study on physiological changes in certain psychosomatic disorders with reference to cortisol, blood glucose and lipid profile.

Plasma cortisol, blood glucose, serum lipids and lipoproteins were estimated in diseased human subjects and normal control volunteers. Serum triglyceride (Tg) total cholesterol (Tc) and cholesterol content of very low density lipoprotein (VLDLc), low density lipoprotein (LDLc) and high density lipoprotein (HDLc) were assayed under lipid profile. Clinical investigations were carried out on 115 subjects which involved 30 control, 25 irritable bowel syndrome (IBS), 30 bronchial asthma and 30 rheumatoid arthritis patients. The results of this preliminary study showed a significant change in the levels of all the biochemical parameters in diseased subjects in comparison with controls. Increased levels of atherogenic lipids, Tg, VLDLc and LDLc were found in rheumatoid arthritis subjects. This suggests that arthritis subjects are relatively at higher risk of developing coronary heart disease. Furthermore hypercholesterolemia may aggravate the risk condition in arthritis patients by artereosclerosis. The significant elevation in the levels of plasma cortisol reveals the fact that rheumatoid arthritis is a stabilized and chronic psychosomatic disorder, since, homeostatic competence is disrupted following decline in the tendency of stress-response to return to normalcy.

A study on physiological changes in essential hypertension and rheumatoid arthritis with reference to the levels of cortisol, blood glucose, triglycerides and cholesterol.

The levels of plasma cortisol, blood glucose, serum triglycerides (TG) and total cholesterol (TC) were estimated in 175 human subjects (50 normal controls, 65 having essential hypertension and 60 suffering from rheumatoid arthritis. The results showed a significant elevation in the levels of plasma cortisol and blood glucose in both the stressed clinical groups with respect to controls. Increased levels of atherogenic lipids (TG and TC) were also observed in diseased group. However, in rheumatoid arthritis the biochemical changes were comparatively more pronounced than in hypertensives. The findings in vitro reveal that rheumatoid arthritis is a relatively more chronic and late onset disorder, since the functional performance of hypothalamo-pituitary-adrenocortical (HPA) axis declines with chronicity and the efficacy of adrenocortical response to return to normalcy becomes impaired.