The objectives of the current study were to detect virulence factors and determine antimicrobial susceptibility of Staphylococcus aureus by using 360 fresh raw chicken meats, collected from 133 chicken shops in Isfahan, Iran, from January 2011 to March 2012. The Staph. aureus isolates were identified using culture and phenotypical methods. The PCR assays were developed with specific primers for the detection of different virulence and antibiotic resistance genes of Staph. aureus. The agar disk diffusion method was used for evaluation of antibiotic susceptibility of Staph. aureus isolated from chicken meat samples. In this survey, 101 out of 360 samples were positive for Staphylococcus (28.05%). In our results indicated, out of 360 samples, 82 (22.77%) were positive for Staph. aureus and, out of 82 positive samples, 96.34% had X-region, 76.92% had fibrinogen clumping factor A, 63.41% had staphylococcal coagulase virulence genes, 26.82% had IgG binding region, and the toxic shock syndrome toxin-1 gene was not isolated in any sample. The methicillin was the highest (82.92%), whereas macrolides was the lowest (34.14%) antibiotic-resistant genes in Staph. aureus-positive samples. Tetracycline had the highest resistant profile (97.56%) in Staph. aureus isolates, followed by methicillin (75.6), sulfamethoxazol (31.7%), trimethoprim (31.7%), streptomycin (31.7%), gentamicin (29.26%), enrofloxacin (28.04%), ampicillin (26.82%), chloramphenicol (20.73%), and cephalothin (17.07%). Statistical analysis showed significant differences between presences of various virulence and antibiotic resistance genes in Staph. aureus isolated from chicken meat samples. It seems that inspection of chicken meat using multiplex PCR is a useful technique for detection of Staph. aureus virulence and antibiotic resistance genes.

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Biological systems provide a wealth of information which form the basis for human-made artificial systems. In this work, the visual system of Octopus is investigated and its polarization sensitivity mimicked. While in actual Octopus retina, polarization vision is mainly based on the orthogonal arrangement of its photoreceptors, our implementation uses a birefringent micropolarizer made of YVO4 and mounted on a CMOS chip with neuromorphic circuitry to process linearly polarized light. Arranged in an 8 x 5 array with two photodiodes per pixel, each consuming typically 10 microW, this circuitry mimics both the functionality of individual Octopus retina cells by computing the state of polarization and the interconnection of these cells through a bias-controllable resistive network.

Mastitis is a common disease in dairy cattle and is an inflammatory response of the breast tissue to bacterial attack to this tissue. Mastitis causes considerable loss to the dairy industry, among the several bacterial pathogens that can cause mastitis; Staphylococcus aureus is probably the most lethal agent because it causes chronic and deep infection in the mammary glands that is extremely difficult to cure. Several virulence factors including coagulase gene are produced by S. aureus and may contribute to its pathogenicity. This study was conducted to investigate the coagulase gene polymorphism of S. aureus isolated from clinical and sub-clinical bovine mastitis milk samples in Isfahan and Chaharmahal va Bakhtiari provinces of Iran. Amplification of the coagulase gene from 86 S. aureus strains isolates by specific primers showed 31 specimens contained 970 bp fragment, and 11 strains contained 730 bp fragment relevant to coa gene (coagulase) in PCR. After enzymatic digestion with AluI, 31 specimens contained three bands: 320, 490, and 160 bp (genotype I) and 11 specimens contained two bands: 490 and 240 bp (genotype VIII) in the RFLP.