جستجوی مقالات مرتبط با کلیدواژه « antibacterial resistance » در نشریات گروه « پزشکی »

The spread of antibiotic resistance and the emergence of MDR strains, especially in gram-negative bacteria, has led to combining antibiotics to treat infections caused by these bacteria. The study aimed to evaluate some antibiotics' synergistic effect on multidrug-resistant Pseudomonas aeruginosa isolates isolated from clinical samplesbetween thyroid dysfunction and asymptomatic bacteriuria in women of reproductive and postmenopausal age.

P. aeruginosawas isolated from Rasht city hospitals (North of Iran) clinical specimens with multiple antibiotic resistance. The antibiotic resistance of isolates was determined by the disk diffusion method. The screening checklist evaluated the synergistic effects of ciprofloxacin, colistin, meropenem, and gentamicin.

The combination of meropenem and colistin in four isolates was additive, and in two isolates was indifferent. The combined effect of ciprofloxacin and colistin was also incremental in 4 isolates and indifferent in 2 isolates. The combined effect of gentamicin and colistin was indifferent in all selected strains.

Results of this study showed that combinations of colistin with ciprofloxacin and colistin with meropenem were successful against resistant isolates, while a combination of gentamicin and colistin showed no synergistic effect. Since the characteristics of each clinical isolate differ from the other isolates, more study with more isolates is recommended to make any precise and definite recommendation.

Microbial resistance to antibiotics has led to serious efforts to discover novel drugs, which is why there is so much interest in the use of herbs. Therefore, the aim of this study was to investigate the antibacterial effect of aqueous, hydro-alcoholic, and alcoholic extracts of Morus nigra in comparison with some common antibiotics. In this experimental study, the zone of inhibition, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the Morus nigra extracts against Staphylococcus epidermidis, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus mutans and Streptococcus pyogenes were determined using the disk diffusion and broth macro-dilution methods. Statistical analysis was performed using the ANOVA test by SPSS software. The results of this study showed that all studied strains were sensitive to different extracts of Morus nigra. The highest antibacterial effect was related to the aqueous extract of Morus nigra, which created an inhibition zone with a diameter of 22.25 against Streptococcus mutans and Streptococcus pyogenes. The lowest inhibition zone (9 mm) was related to the alcoholic extract of Morus nigra against Pseudomonas aeruginosa. The MIC values of different extracts of Morus nigra against test bacteria varied from 0.78 to 3.12 mg/ml and MBC values were between 3.12 and 50 mg/mL. Based on the findings of this study, the aqueous extract of Morus nigra has shown strong bactericidal properties against all studied bacterial strains, which indicates its potential for therapeutic application.

The COVID-19 outbreak offers an unmatched chance to take advantage of personalized medicine's benefits for the protection, detection, medication, monitoring, and administration of a fresh public health crisis. Antibiotics, which were formerly regarded as miracle cures and among the most difficult life-saving discoveries of the twentieth century, are now posing a hazard to society as a result of overuse and abuse. Antimicrobial resistance (AMR) is a widespread issue that is becoming worse, and the current COVID-19 pandemic might make things even worse. It has been shown that a significant portion of Covid-19 patients gets secondary microbiological infections. The medical industry is now facing difficulties because of this. As a result, several non-antibiotic techniques have been sought, and their processes have been examined, to slow the spread of AMR.

Pseudomonas aeruginosa (P. aeruginosa) is a common bacteria associated with burn infections and resistance to a wide range of disinfectants and antimicrobial agents which is able to produce different virulence factors. In this study, the susceptibility of P. aeruginosa isolates from burn (burn=57) and hospital environment (HE=19) to antimicrobial agents and chemical disinfectants was determined by disc and well diffusion agar method, respectively. The results showed 100% sensitivity to polymyxin B, while sensitivity to other agents were low and ranged from 40.8% for imipenem and amikacin to 6.6% for ceftizoxime. Among the disinfectant used the mean diameter of inhibition zones (DIZ) was higher for deconex while nitrofurazone had the lowest DIZ. In most cases the HE isolates were significantly more susceptible to disinfectants and antimicrobial agents compared to burn isolates (P≤0.01). The genes for the exoenzyme T, Y, U and S were detected in 100%, 89.8%, 43.4% and 48.7% of the isolates respectively. Prevalence of exo U and exoY was significantly higher in the burn isolates compared to HE isolates (P=0.001). The results of this study indicate significantly higher level of resistance against the majority of the antimicrobial agents in the burn isolates compared to HE isolates which was significantly higher than the environmental isolates. The prevalence of T3SS effectors proteins and their pattern were also different in the burn and the HE isolates, indicating a divergence in pathogenicity of the burn isolates from those of the environmental isolates.

Shiga toxin-producing Escherichia coli (STEC) strains are considered as one of the most important widespread food-borne pathogens, which cause diarrhea and life threatening diseases, such as hemolytic uremic syndrome, in humans. More recently, the STEC strains have also been incriminated to cause diarrhea and hemorrhagic colitis in calves; enteropathogenic E. coli (EPEC) also causes diarrhea in neonate animals.. This study aimed to study the prevalence and antibacterial resistance patterns of STEC and EPEC in fecal samples from diarrheic calves in Mashhad and Garmsar districts, Iran.. A total of 115 fecal samples were collected from diarrheic animals, 75 from Mashhad and 40 from Garmsar districts. A total of 146 E. coli isolates were obtained from culture and subjected to multiplex-PCR assay targeting stx1, stx2, eaeA and ehly virulence genes. The antibacterial resistance patterns of the virulence-positive isolates were determined using disc diffusion method.. Eight samples (6.9%) carried the strains with positive results for at least one of the tested virulence genes. Five samples (4.3%) contained the stx-positive strains (STEC) and three (2.6%) carried the eaeA-positive and stx-negative strains, which were categorized as EPEC. In nine virulence-positive E. coli isolates, stx1 (n = 6) was the predominant virulence gene, followed by ehly (n = 5), eae (n = 4), and stx2 (n = 2). Antibacterial resistance patterns of virulence-positive isolates were also determined and nine resistance profiles were discriminated; higher rates of resistance were observed in isolates from Mashhad.. This study indicated that other pathologic factors might play a more important role in calf diarrhea in the studied areas, but public health significance of these strains should not be overlooked..

Helicobacter pylori (Hp) is related to gastritis, gastric ulcer, duodenal ulcer, and mucosal carcinoma. Emergence of multidrug resistant Hp strains encouraged the researchers to find new effective drugs. Especially medicinal herbs and plants which usually shows less side effects. The aim of this study was in vitro assessment of anti Hp activity of total extract of Tribulus terrestris (T. terrestris Benzoxacin, a local Iranian medicinal plant and its fraction Benzoxacin. total aqueous extract of aerial parts of the plant was prepared and liquid extraction with petroleum ether was used to separate its components. LC/MS system proved the existence of Benzoxazine derivative in the water fraction and the third''s fraction. Anti (Hp) effects of total extract and its third fraction were examined by cup plate method and using standard MacFarland. 50 biopsy samples of antrum were detected from patients who were endoscopic candidates in Milad and Fayazbakhsh hospitals of Tehran during 2011. All samples were isolated, diagnosed based on standard methods and biochemical tests and confirmed by PCR method for ureC gene, too. Different dilutions (250, 500,750 and 1000 mg/ml) of total extract were prepared. Clarythromycin (Clr) E-test strips and an identified Hp OC1096 was used, simultaneously. Of 50 biopsy samples, 12 Hp strains were isolated. Rapid urease test were positive in all expect one biopsy sample. Existence of ureC gene in all isolates were confirmed expect one strain by PCR. By cup plate method, resistant to concentrations of 1000 and 750mg/ml were detected in 50% of Hp isolates and 66.6% of them were resistant to concentrations 250 and 500 mg/ml. Also, 83.3% of Hp strains were resistant to Benzoxacin fraction. Clarythromycin sensitivity detected in 83% of Hp isolates, simultaneously. This study was done as a pilot study for in vitro evaluation of antibacterial effect of total extract of T. terrestris by cup plate method. Existence of high resistant rate (≥50%) to different concentrations T. terrestris aqueous extract seems doing test on more Hp strains in future studies is highly recommended. In contrast of the similarity of Benzoxazin structure to Ofloxacin, existence of 83.3% of resistance among tested isolates showed no anti Hp effectiveness of this fraction.