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Background: Streptococcus agalactiae, also known as Group B Streptococcus (GBS) is a commensal organism in the urogenital tract and rectum in approximately 25% of the healthy adult female population. The bacterium is the leading cause of bacterial meningitis, pneumonia, and sepsis in human infants.
Materials and Methods: Our study was performed over a three - month period from April to June 2014. Midstream specimens of urine were collected from outpatients suspected of having a bacterial urinary tract infection, which had not received any antibiotics. Group B Streptococci isolates were confirmed by typical colony morphology and identified by differential tests. Antibiotic susceptibility testing was carried out by disk diffusion method on Mueller Hinton agar (Merck, Germany) based on (CLSI) Guidelines 2012.
Results: GBS strains were isolated from 264 (21.1%) cases (out of 1249 positive bacterial urine cultures). The higher prevalence was recorded in the 15-44 and 45-64 age groups. Antibiotic susceptibility tests revealed that vancomycin, penicillin, and linezolid had the lowest, and tetracycline had the highest resistance rate.
Conclusion: In conclusion, the results of the present study confirm the universal susceptibility of GBS strains to the penicillin family and assert the use of penicillin or ampicillin as the first drug of choice for treatment and prophylaxis against GBS infections. However, it is important to perform antibiotic susceptibility testing whenever penicillin could not be prescribed.

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Objective: DNA markers are one of the most important indicators for estimating Molecular weight of DNA samples, although it used in widespread medical and research laboratories. These markers are very divers and have been prepared in different manners and from different sources of DNA. But unfortunately, DNA markers haven't been made in our country and all of the markers that we use are made in a foreign country. The aim of this research is settings a suitable technology to produce this product in the lab. Material and Methods: With this aim, we used two different strains of lambda: c1857sam7 and EMBL3A both of which are lytic phages as a DNA source. These were grown in the suitable host, after plaque appearance on the bacterial lawn, suitable titer for phage collecting was determined. We also optimized plasmid purification method for extraction of pBR322, pUC18 and recombinant VZV plasmid DNA and designed fragments in the markers have been constructed by digesting these DNAs with variant enzymes. Results: In this study, we made seven DNA markers out of which four of them were made for the first time in the world (/Hind III/BamH1, /Hind III/EcoR1, Sam2, Sam1) and although foreign models of three of them exist but they were made in our country for the first time (/Pst I, /Hind III, pBR332/MspI). Conclusion: The other goal of this study was to determining the best conditions for maintaining and preserving these markers in the lab which was successfully performed.