Vol 7 No 1-2 (2018)

Review Articles

  • XML | PDF | downloads: 386 | views: 594 | pages: 1-12
    Background:      Typhoid infection is an insidious onset type of fever and some other gastrointestinal disorders which may have a fatal outcome. The causative agents are Salmonella typhi, Salmonella paratyphi A, and Salmonella paratyphi B.  Clinical features include, gradual rising fever, white coated tongue, and severe degree of malaise, drowsiness and pain in abdomen, perforation with bleeding in the intestines, shock and death. It involves mostly male victims of school going age. It is water born disease which spreads due to poor sanitation mostly in congested populated areas. According to World Health Organization sixteen to seventeen million typhoid fever cases were reported annually, out of which 600,000 died. Typhoid fever is 10 to 29 times more in subcontinent than China. Infection only occurs when food is handled by infected person. Isolated strains of Salmonella spp from suspected cases show resistance against routine antibiotics and the modern antibiotics are much more expensive and un affordable. Conclusion:    Need of this review is especially for Silver Nanoparticles (AgNPs) manufactured by some types of fungi introduced by recent researchers have an edge to control or treat some sort of infections due to their antibacterial properties. In this study these (AgNPs) in the form of suspension, give positive results against the Salmonella species. It enables us to treat the typhoid infection in a less expensive way.

Original Articles

  • XML | PDF | downloads: 514 | views: 744 | pages: 13-21
    Background:      Considering the importance of new antibiotics, the potential antibacterial activity of ethyl acetate and Methanol extracts of Securigera securidaca, Withania sominefra, Rosmarinus officinalis and Aloe vera plants against important human pathogens was studied.   Methods:   Streptococcus pneumoniae, Enterococcus faecalis, Proteus mirabilis, Staphylococcus aureus, E. coli, P. aeruginosa were the pathogenic bacteria used to determine the antibacterial effect of ethyl acetate and mathanol extracts of Securigera securidaca, Withania sominefra, Rosmarinus officinalis and Aloe vera in broth micro-dilution method. Results:      The results of studying the methanol extract of S. securidaca with the lowest inhibitory concentration of 25, showed that all used bacterial pathogens were inhibited at this concentration, while the lowest inhibitory concentration of ethyl acetate extract of Securigera securidaca was 12.5, which were P. mirabilis and S. aureus is inhibited in this concentration. The highest bactericidal concentration (MBC) of S. securidaca ethyl acetate extract was 100, and S. aureus, P. aeruginosa were inhibitory at this concentration. The lowest inhibitory concentration of methanol extract of W. sominefra was 6.25, which S. pneumoniae, P. mirabilis, S. aureus and E. coli bacteria were inhibited at this concentration, while the highest inhibitory concentration was observed against P. aeruginosa (25 ppm), The lowest inhibitory concentration of the ethyl acetate W. sominefra extract was 3.1ppm in comparison with P. mirabilis and E. coli. Conclusion:     In conclusion, it seems that S. securidaca, W. sominefra, R. officinalis and Aloe vera extracts could inhibit the growth of all of the mentioned bacteria.
  • XML | PDF | downloads: 561 | views: 759 | pages: 22-30
    Background:    Nosocomial infections has always been a major problem for health care and lead to increases in morbidity and mortality in hospitalized patients. The aim of this study was to determine the contamination of personnel and hospital environment and device with nosocomial infections pathogens. Methods:  Wet swab was used to sampling from the hospital personnel and equipment in different wards of a hospital in Isfahan, Iran. Culture and isolation of strains were done according to the standard microbial methods. Identification was based on gram staining, microbial and biochemical tests.   Results:  Overall 236 samples; 123 and 113 samples were collected from 91 hospital personnel and hospital environment and devices respectively. S. aureus was isolated from 14.2%, 15.3% and 5.4% of personnel hands, uniform and throat respectively. The cases of Enterobacteriaceae were isolated from personnel hands, uniform and throat as 13.9%, 4.3% and 3.27% respectively. P. aeruginosa was isolated from personnel hands (4.3%), uniform (6.5%) and throat (6.5%). Conclusion:   S. aureus, Enterobacteriaceae and P. aeruginosa were the most prevalence bacteria that isolated from the personnel hands, uniforms, throats and hospital environment and devices. Personnel hands were the most contaminated part considering both the numbers and diversity in isolated organisms. Contamination of the hospital personnel and hospital environment and devices have a main role in dispersion of the nosocomial pathogens in hospital environment. With a good hygienic administration and an excellent healthy management planning in hospitals can be inhibit the dispersion of nosocomial pathogens in hospitals environment.  Hospital environment and devices, Hospital personnel, Microbial Pathogens, Nosocomial infections.
  • XML | PDF | downloads: 373 | views: 669 | pages: 31-35
    Background:      The importance of common diseases between humans and animals (zoonosis), and whose health impacts on the community individuals are obvious to everyone. One of these diseases is human infection with Coxiella burnetii and Q fever. Due to the importance of this subject and lack of published documents regarding the presence and distribution of this bacterium in Lorestan province, we aimed to determine the prevalence of C. burnetii in this area. Methods:  A cross-sectional study was conducted from July 2013 to March 2014. A total of 500 raw milk samples was collected from 130 cattle, 200 sheep, and 170 goats in both warm and cold seasons from 20 selected villages in Khorramabad and Nourabad regions, Lorestan province, Iran. The presence of C. burnetii in collected specimens was tested by polymerase chain reaction (PCR). Results:     A total of 9 (1.8%) milk specimens were positive for the presence of C. burnetii (3 sheep milk samples and 6 goat milk samples). All positive milk samples were obtained from 2 villages (Daraei and Ghalebi) around of the Khorramabad region during the winter season. However, all collected samples from Nourabad were negative for presence of C. burnett.   Conclusion:     The presence of C. burnetii in raw milk of ruminants in the cold seasons could be related to climate changes. Therefore, further investigations via various methods seems to be needed.
  • XML | PDF | downloads: 515 | views: 587 | pages: 36-43
    Background:    Plant extract as a potential phyto-reducer is used as a simple, non-toxic and ecofriendly green synthesis method of silver nanoparticles (AgNPs). In this study biosynthesis of AgNPs using leaves extract broth of Amaranthus retroflexus as both reducing and stabilizing agent was analyzed. Antibacterial activity toward resistant human pathogenic bacteria Escherichia coli and Pseudomonas aeruginosa and also against plant pathogenic bacteria Pseudomonas syringae, Xanthomonas oryzae, was studied. The biosynthesized AgNPs were also evaluated for their increased antimicrobial activities with Ciprofloxacin antibiotic against some of the tested bacteria. Methods:   The formation of green synthesized nanoparticles from aqueous solution of silver nitrate was first screened by measuring the surface plasmon resonance peak at 300-800 nm using UV–vis spectroscopy. The morphology, size and Crystalline structure of the synthesized AgNPs was determined using Transmission Electron Microscope (TEM), DLS and X-ray diffraction analysis. For antibacterial studies two-fold serial dilutions were made in NB medium (Qlab Canada) and the growth of the cultures was monitored by measuring the optical density value at 630 nm (OD630) with microplate reader (Biotech ELX 800) after 24 hours of incubation to obtain the MIC of the AgNPs. Results:     The results indicated that the phyto-synthesized AgNPs were spherical with an average size of 48 nm. XRD peaks indicate the presence of a face centered cubic (fcc) structure of crystalline AgNPs.  The AgNPs showed highly potent antibacterial activity toward the tested bacteria. Also the combined antibacterial activity of Ciprofloxacin with AgNPs reduced the MIC of antibiotic from 0.125 µg/ml to 0.0625 µg/ml toward P. aeruginosa and Ciprofloxacin MIC against P. syringae decreased from 0.25 to 0.0625 µg/ml in combination with 6.25, 12.5, and 25 µg/ml of AgNPs. Conclusion:     Results from the current study suggested that the silver nanoparticles successfully can be synthesized using Amaranth leaf extract. The phyto-synthesized nanoparticles could have potential antibacterial applications and show synergistic effect in combination with Ciprofloxacin antibiotic.
  • XML | PDF | downloads: 291 | views: 594 | pages: 44-49
    Background:       it is known that plants have many potential benefits for human health. The purpose of this study was to investigate the antimicrobial properties of several commonly used herbs against specific microorganisms responsible for disease and food spoilage. Essential oils of yarrow, fennel, juniper and marjoram were evaluated, with respect to their efficacy at controlling the growth and survival of several common bacterial and fungal microorganisms. Methods:     The agar diffusion test was used to test the essential oils efficacy at inhibiting microbial growth. The following microorganisms were tested with varied results: Escherichia coli, Aspergillus niger, Enterococcus faecalis, Salmonella typhimurium, Salmonella anatum, Staphylococcus aureus, Candida albicans, Penicillium glaucum and Bacillus cereus. Results:      Marjoram showed the highest inhibition with a zone up to 14 mm. Juniper and fennel essential oils were also highly inhibitory to Candida albicans and the other tested bacteria and fungi. Conclusion:       In conclusion, some of the oils were highly effective at inhibiting the studied microorganisms. This knowledge may be useful for further examining the efficacy of pathogenic prevention and food preservation by studied essential oils.
  • XML | PDF | downloads: 449 | views: 525 | pages: 50-56
    Background:      Acquiring genetic determinants with antibiotic resistance and mutation in regulatory genes of Acinetobacter baumannii can made many problems in treatment of patients. The AdeIJK pump are associated with decrease susceptibility to trimethoprim, fluoroquinolones, β-lactams, novobiocin, tetracycline, lincosamides, erythromycin, chloramphenicol and  AbeM pump can decrease the MIC of chloramphenicol, trimethoprim, aminoglycosides and fluoroquinolones. Upregulation of drug transporters systems, modifications in gyrA and parC genes have major role to fluoroquinolones resistance in A. baumannii. The aim of this study was investigation the contribution of adeJ and abeM pumps in extrusion of ciprofloxacin in A. baumannii. Methods:     For confirmation of species the blaOXA-51 gene was applied. Disk diffusion method was performed for antimicrobial susceptibility test. For illustration of active efflux pumps the CCCP and ciprofloxacin were used to determine MIC. To detect the RNA transcript of AdeJ and AbeM pumps in isolates collected from two hospitals from July 2016 to March 2017 qRT-PCR was carried out. Results:    The MICs of ciprofloxacin decreased 32-fold or more in 7 strains, 16-fold in 2 strains, 8-fold in 10 strains, 4-fold in 25 strains and 2-fold in 6 strains after adding CCCP. Overexpression of the adeJ (84%) and abeM (88.63%) genes were indicated by qRT-PCR. Conclusion: Efflux pups inhibitor are new approach for increase susceptibility to many classes of antibiotics. In A. baumannii strains transporting system may have contribution in ciprofloxacin resistance as shown with this study.
  • XML | PDF | downloads: 241 | views: 361 | pages: 57-65
    Background:    Antibiotic resistance among bacteria has been one of the health problems in the world since the past. A type of resistance is due to the production of enzymes called beta-lactamases which is cause resistance to beta-lactam drugs and led to the emergence of new types of Extended-Spectrum Beta-Lactamases (ESBLs). Due to the importance of ESBL producing strain in uncontrolled hospital infections, the present study was Designed for evaluation of ESBL frequency in isolated Enterobacteriaceae from clinical specimens in an AJA hospital in Tehran. Methods:    In this study, 100 clinical specimens collected from AJA. All specimens were identified by standard bacteriological and biochemical methods and antimicrobial susceptibility test was performed using disc diffusion method. Production of broad-spectrum beta-lactamase enzymes was evaluated using a mixed disk method with cefotaxime and ceftazidime antibiotics with clavulanic acid or alone. Results were interpreted according to CLSI guidelines. Results:    From 100 specimen, 75 isolates (75%) were confirmed as an Enterobacteriaceae family. Most sensitivities observed in Imipenem (97.33%), Meropenem (94.66%), Piperacillin (68%), and Gentamicin (64%). Overall 42.66% of isolates produced ESBLs. Conclusion: According to the results, broad-spectrum beta-lactamase production in isolated bacteria from a clinical specimen of AJA hospital was high and 42.66% of isolates produced ESBLs. Due to the high resistance of these strains to most common antibiotics, identification of these pathogens, applying control methods in relation to the production and release of this type of bacteria and the correct use of antibiotics should be put on the agenda.