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Abstract Background and objectives: Helicobacter pylori is a helical gram negative bacterium with polar flagella, discovered by Warren and Marshall in 1983. Helicobacter pylori exist in the stomach mucus tissue of less than 20% of people under 30 years old, but this amount would increase up to 40% and 60% in 60- year- old people. The aim of this study was to compare three methods of culture media, direct slide staining and the urease test for the rapid diagnosis of bacterium in case of peptic or duodenal ulcer. Material and Methods: In This descriptive study, duplicate biopsy specimens were taken from 82 clients referring to four different Hospitals .In endoscopy room of the Hospitals, a rapid urease test were carried out on one of duplicate specimens for the presence or non-presence of Helicobacter pylori. In order to see the Helicobacter pylori in the tissues, three slides using foushin, giemsa, and gram staining were prepared from the second specimens. Then, the specimens were incubated into selective culture media and incubated for 4-6 days in micoraerophilic condition. Results: Of 82 tested specimens 70(85.5%) and 66(80.5%) are identified as Helicobacter pylori by positive urease and culture medium, respectively. The frequency of foushin, giemsa, and gram staining are 67 (81.7%), 66 (80.5%), and 61 (74.4%), respectively. The foushin staining is the best with 100% sensitivity among the other methods. Conclusion: Based on difference between proportions, There is no significant difference between staining methods (foshin, giemsa, gram staining) and culture media in all cases. Key words: Helicobacter pylori, microscopic methods, urease test, culture media, identification

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Background and objectives: Developing scaffolds is important for tissue engineering and repairing damaged tissues. The present study aimed to investigate effects of pre-incubation of an electrospun silk fibroin scaffold in complete and serum-free media on proliferation and survival of cells seeded on the scaffold.
Methods: After removing sericin from the silk cocoon and preparing the fibroin solution (3% w/v), the electrospun silk fibroin scaffold was fabricated and its morphology was evaluated by scanning electron microscopy. The scaffolds were pre-incubated in complete and serum-free Dulbecco's Modified Eagle media for one hour (short-term) and 10 days (long-term), and the hydrophilicity of scaffolds was evaluated by measuring the water contact angle. Rat bone marrow mesenchymal stem cells were seeded onto the scaffolds, and cell survival and genomic DNA concentration were evaluated after 21 days.
Results: The short-time pre-incubation of electrospun silk fibroin scaffolds in the complete medium increased the proliferation of seeded cells because of serum protein adsorption. In addition, long-term pre-incubation of the scaffolds in the complete and serum-free media increased cell proliferation due to the increased hydrophilicity of the scaffold (p<0.05). However, only long-term pre-incubation of the scaffolds in the complete medium had a significant effect on cell survival.
Conclusion: The results demonstrated that long-term pre-incubation of the scaffolds in the complete medium have more profound positive effects on cell survival and proliferation compared to short-term pre-incubation.

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Abstract
Background: Biofilm formation in Staphylococcus aureus (S. aureus), mediated by the ica operon, is a key virulence factor. This study examined how different glucose-supplemented broth culture media influence biofilm production and ica gene expression in S. aureus.
Methods: The phenotypic ability to adhere to a polystyrene surface and to produce slime layer were evaluated using microtiter plate test (MtP) and Congo red tube test, respectively. Using PCR, the presence of intercellular adhesion (ica) locus in S. aureus strains was confirmed and subsequently, quantitative real-time RT-PCR was performed to investigate transcription of icaA in various media including Tryptic soy broth (TSB), Brain-heart infusion broth (BHIB), (Nutrient broth) NB and (Muller-Hinton broth) MHB contained 0, 0.25, 0.5, 1 and 2% glucose.
Results: Our results showed that although all of the studied strains adhered to the wells of polystyrene microtiter plates, the optimum rate of biofilm formation was observed for TSB medium contained 1% glucose, but biofilm formation was not significantly different in NB, MHB and BHIB media. Supplementation of all media with 1% glucose led to the highest production of biofilm formation and in all media transcription of icaA was increased with glucose addition to one present.
Conclusions: The results of the present study indicated that TSB medium supplemented with 1% glucose was the most appropriate medium for evaluation of biofilm formation by S. aureus isolates.