Showing 2 results for Doosty
M Doosty, H Shirvany,
Volume 56, Issue 1 (30 1998)
Abstract
The function of Helicobacter pylori (H.pylori) is confirmed as one of the factors which motivates gastric and duodenal ulcer and gastritis. Various methods are used to diagnose the infection. Serological tests are the easiest and most harmless for the patients. Probably, H.pylori strains in Iran are different from the strains in other countries. Hence, it seems neccessary to design a specific serological test to recognize and identify different strains of bacterial antigenic proteins of Iranian patients.
Since the most manifest and specific to these bacterial antigens are the "Outer Membrane Protein" (OMP), therefore, the first necessary step is to separate and purify H.pylori OMP and then to identify antigenic proteins.
In this study, we received bacteria colony that belonged to 15 patients with gastric or duodenal ulcer, which had been growed in blood agar or brucella broth. After processing such as washing, freezing and defreezing, sonicating, centrifugation with high speed (10,000 g) and treatment with sarcosyl, the sarcosyl insoluble fraction was extracted. Sodium Dodecyl Sulfate - Poly Acrylamide Gel Electrophoresis (SDS-PAGE) was preformed. From all 15 OMP specimens, we isolated protein bands.
The first two bands with higher MW, were major bands and the two lighter bands were the minor bands. Approximate MW of these 4 proteins are equal to 67000, 61000, 30000 and 17000 dalton
R Mohammadi , M Doosty ,
Volume 57, Issue 1 (7 1999)
Abstract
Oxidation of low density lipoproteins (LDLs) is belived to be an important step in the pathogenesis of atherosclerosis. During oxidation, LDL particle undergoes a large number of structural changes that alters its biological properties, so it becomes atherogenic. To study atherogenic proteins, usually two forms of modified LDLs, including Cu2+-oxidized LDL (ox-LDL) and malondialdehyde (MDA) modified LDL (mal-LDL) are used. In this study, LDL was isolated from 72 ml freshly prepared plasma by sequential Floatation Ultracentrifugation (SFU), which resulted in separation of 12.5 mg LDL protein. LDL oxidation was accomplished in Phosphate Buffered Saline (PBS) with 2µM cupric sulfate, and mal-LDL was prepared by incubating LDL in PBS with 0.5 M solution of freshly prepared MDA. These modifications were evaluated by measuring optical density at 234 nm, Thiobarbitoric Acid Reactive Substances (TBARS), and electrophoretic mobility at pH 8.6. The increase of 234 nm absorption reflected initiation of LDL oxidation. TBARS of ox-LDL and mal-LDL was 80 Nm MAD/mg LDL protein and 400 nm MDA/mg LDL protein, respectively. Electrophoretic mobility of ox-LDL and mal-LDL, in respect to native LDL (n-LDL), were increased.
