Background: The increasing use of telecommunication devices such as Wi-Fi modems and mobile phones in the recent years can change the cellular structure of microorganisms so the generation of electromagnetic waves has led to concern in the community whenever be exposed to these fields and may have harmful effects on human health.Material and Methods: Standard strains of bacteria were prepared on Mueller-Hinton agar for bacterial growth to obtain 0.5 McFarland turbidity (1.5 × 108 CFU) of bacteria. Antibiotic susceptibility testing using the Kirby-Bauer disk diffusion method was done. For Staphylococcus aureus and Pseudomonas aeruginosa, antibiotics susceptibility test was conducted. The test group was exposed to electromagnetic waves emitted by mobile phone simulator with a frequency of 900 MHz and the control group didin’t exposed.Results: The results revealed that increasing duration of exposure to electromagnetic waves emitted by the mobile simulators with a frequency of 900 MHz especially after 24 h of exposure, can increase bacterial resistance in S. aureus, and P. aeruginosa.Conclusion: Several factors can cause bacterial resistance against antibiotics. One of these factors is the electromagnetic waves emitted from mobile simulator with a frequency of 900 MHz, which can increase the permeability of the cell wall of bacteria.

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Background: Cervical cancer cells are known as radioresistant cells. Current treatment methods have not improved the patients’ survival efficiently; thus, new therapeutic strategies are needed to enhance the efficacy of radiotherapy. Gold nanomaterials with different shapes and sizes have been explored as radiosensitizers. The present study compared the radiosensitizing effects of gold nanorods (AuNRs) with spherical gold nanoparticles (AuNPs) on the HeLa cell line irradiated with megavoltage X-rays. Materials and Methods: The cytotoxicity of AuNRs and AuNPs on HeLa cells in the presence and absence of 6-MV X-ray was investigated using the MTT assay. For this aim, HeLa cells were incubated with and AuNPs and AuNRs at various concentrations (5, 10, and 15 µg/mL) for 6 hours. Afterward, HeLa cells were irradiated with 6-MV X-ray at a single dose of 2 Gy. Results: The results showed that the addition of AuNRs and AuNPs could enhance the radiosensitivity of HeLa cells. Both AuNRs and AuNPs showed low toxicity on HeLa cells, while AuNRs were more toxic than AuNPs at the examined concentrations. Moreover, it was found that AuNRs could enhance the radiosensitivity of HeLa cells more than spherical-shaped AuNPs. Conclusion: This study revealed that the shape of nanoparticles is an effective factor when they are used as radiosensitizing agents during radiotherapy. [GMJ.2020;9:e1581]

Background: Overuse of antibiotics is a cause of bacterial resistance. It is known that electromagnetic waves emitted from electrical devices can cause changes in biological systems. This study aimed at evaluating the effects of short-term exposure to electromagnetic fields emitted from common Wi-Fi routers on changes in antibiotic sensitivity to opportunistic pathogenic bacteria. Materials and Methods: Standard strains of bacteria were prepared in this study. Antibiotic susceptibility test, based on the Kirby-Bauer disk diffusion method, was carried out in Mueller-Hinton agar plates. Two different antibiotic susceptibility tests for Staphylococcus aureus and Pseudomonas aeruginosa were conducted after exposure to 2.4-GHz radiofrequency radiation. The control group was not exposed to radiation. Results: Our findings revealed that by increasing the duration of exposure to electromagnetic waves at a frequency of 2.4 GHz, bacterial resistance increased against S. aureus and P. aeruginosa, especially after 24 hours (P<0.05). Conclusion: The use of electromagnetic waves with a frequency of 2.4 GHz can be a suitable method for infection control and treatment. [GMJ.2020;9:e1580]

A total of 120 random samples of fresh (30) and processed (90) beef and poultry meat products were collected from different supermarkets in Menoufia governorates .these samples were examined for the presence of multi-drug resistant Stx1 harboring E. Coli, the obtained results revealed that the highest incidence of E.COLI in processed samples were recorded in chicken fahita (46.66 %), while beef burger showed the lowest incidence(20%),but the highest incidence in fresh samples were recorded in chicken thigh(40%),on the other hand, chicken breast and fresh beef were the same incidence (20%).The illustrated results showed that the serovars O2:H6 producing Stx1,while the serovars O91:H21,O86,O153:H2 and O44:H18 which isolated from different products producing Stx2, these serovars showed multi-drug resistance to major group of antimicrobials.

The present study was performed on 120 random samples of fresh chicken meat cuts of Drumstick, thigh and breast (40 of each) which were purchased from different supermarkets and retail chicken butchers at Kaliobia Governorate, for detection of virulence genes responsible for Staphylococcus. aureus enterotoxins production by using PCR.A total of 33 examined samples were positive for S.aureus counts represented as 13(32.5%) from drumstick samples; 11(27.5%) from thigh samples and 9(22.5%) from breast samples. The results revealed that 8 strains out of 10 random examined strains by SET-RPLA test were enterotoxigenic and classified according to type of toxin into (3A;1C,2D and 2A&C).Moreover, PCR results cleared that; sea gene was detected in 4 studied strains; seb gene in one strain and sec; sed and see genes were detected in 3 strains out of 10 studied strains.

The study was performed on 120 random samples of fresh chicken meat cuts of Drumstick, thigh and breast (40 of each) purchased from different supermarkets and retail chicken butchers in Kaliobia governorate to evaluate their bacterial contamination. The bacteriological examination revealed that the mean values of APC, Staphylococci aureus counts (cuf/g) in drumstick samples were 7.47×10 4 ±0.31 ×10 4 ; 2.31×10 3 ±0.11 ×10 3 & 0.26×10 3 ±0.07 ×10 3 , 6.51×10 4 ±0.30×10 4 ; 2.21×10 3 ±0.11×10 3 in thigh& 0.22×10 3 ±0.07×10 3 , and 6.13×10 4 ±0.32 ×10 4 ; 1.99×10 3 ±0.09 ×10 3 & 0.19×10 3 ±0.06×10 3 in breast samples, respectively. Coagulase positive aureus strains were isolated from the examined fresh chicken meat cuts represented as 32.5% in drumstick 27.5% in thigh and 22.5% in breast samples. The isolated strains were highly resistant for methicillin followed by oxacillin; ampicillin; cefotaxime and amoxicillin. Meanwhile, they were highly sensitive to ciprofloxacin followed by enrofloxacin and gentamycin.