Tehran University Medical Journal

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Background: Helicobacter pylori (H. pylori) is one of the major causes of peptic ulcer, gastritis and gastric cancer. This bacterium has a special lipopolysaccharide (LPS), which is responsible for its pathogenesis and its high resistance against gastric acid and escape from the human immune system. This property makes it a target for further research and diagnostic goals. In this study, the extraction of the LPS and separation from the outer membrane is required.
Methods: The LPS was extracted from the outer membrane, or envelope, of H. pylori obtained from patients suffering from gastritis, gastric ulcer and gastric cancer. LPS extraction was performed using the proteinase K method. SDS-PAGE and silver staining were applied to investigate the electrophoretic pattern of the LPS. This pattern was compared with that of E. coli serotype O111:B4 and Salmonella serotype ATCC 14028.
Results: The extracted LPS has a ladder-shaped electrophoretic pattern and the bands are located in three groups: high, medium and low molecular weights.
Conclusion: The distribution of the bands of the ladder-shaped electrophoretic pattern is caused by the different number of oligosaccharide chains associated with the LPS. The high molecular weight bands represent S-LPS and the low molecular weight bands represent the R-LPS, which lacks the O-chain.

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Background: Several randomized controlled trials have demonstrated the safety and efficacy of drug eluting stents (DES) in selected groups of patients with less complicated diabetes. We conducted this study to determine how an unselected group of diabetic patients in Iran fare following DES implantation.

Methods: Data were collected on 147 consecutive diabetic patients who underwent percutaneous coronary intervention (PCI) with the implantation of at least one DES at the Tehran Heart Center from June 2003 to September 2005. Clinical follow-up was performed by timely scheduled visits at one, four and nine months following DES implantation. Nine months of follow-up was completed for 94.5% of the patients. The primary endpoint was the occurrence of major adverse cardiac events (MACE), which include cardiac death, myocardial infarction and target vessel revascularization (TVR). In-hospital complications were the secondary endpoint.

Results: A total of 158 coronary artery lesions were treated with DES in 147 diabetic patients (mean age = 56.4±8.92 years, 57.1% were men). During the nine-month follow-up, MACE occurred in 3.4% of patients, with a myocardial infarction rate of 1.4% and TVR rate of 1.4%. Considering one patient who underwent TVR due to acute stent thrombosis following angioplasty (during hospitalization) the total number of TVR reached 3 (2%). Only one patient (0.7%) died of cardiac death, which occurred after the procedure and before discharge. In-hospital complications occurred in six patients (4.1%) five patients suffered from myocardial infarction.

Conclusions: PCI with DES seems to be safe and effective in diabetic patients. However, more studies with larger study populations and longer follow-up are required to confirm this issue.