infectious diseases are one of the most common causes of morbidity and mortality and the spread of resistant microorganisms is playing a significant role in this regard. the purpose of this study was to assess the trend in antimicrobial resistance of gram-positive bacteria at the main referral teaching hospital in tehran during a 4-year period. all patients' biological isolates such as blood, u...

Background: Neonatal sepsis is one of the most important causes of infant mortality in developing countries. The causative organisms for sepsis are various in different regions across the world. The aim of this study was to determine the frequency of microbial agents and drug resistance pattern of the neonatal sepsis in newborns admitted to the neonatal intensive care unit (NICU) at Alzahra Hos...

background: urinary tract infection (uti) is considered as the most common bacterial infectious disease seen among the pediatric patients. the aim of this study was to investigate the prevalence and antimicrobial susceptibility of bacterial uropathogens isolated from the pediatric patients with urinary tract infections. methods: this descriptive study was conducted in children medial center, te...

The dnaK operon from Bacillus subtilis and other Gram-positive bacteria with low G + C DNA content contains additional heat-shock genes, including hrcA. The hrcA gene encodes a transcription factor that negatively regulates heat-shock genes and is uniformly present in all Gram-positive bacteria studied to date. An hrcA homologue is also present in Synechocystis species, Leptospira interrogans, ...

A total of 2318 heterotrophic nitrogen removal (HNR) bacteria isolated from piggery wastes (after biogas container) were classified in four kinds of heterotrophic ammonia-oxidizing bacteria (569 isolates), nitrite-oxidizing bacteria (580 isolates), nitrate-oxidizing bacteria (600 isolates) and heterotrophic nitrifying and denitrifying bacteria (569 isolates). The virtually complete 16S rRNA gen...

abstract background: streptococcus mutans in the oral cavities sable to produce mutacin (bacteriocin-like substances) with antibiotic properties. the aim of this study was to investigate the frequency and expression of genes encoding mutacins typei, ii, iii and iv and also two of 8 genes in a cluster encoding the putative bacteriocins, the designated bsm 283, bsm 299, bsm 423, bsm 1889c, bsm 18...

In vitro antibacterial and antifungal activity of the chloroform extracts of the root and the stem of Andrographis paniculata at different concentrations were screened against gram positive bacteria Staphylococcus aureus, Bacillus subtilis, gram negative bacteria Escherichia coli, Proteus vulgaris and fungi Aspergillus niger, Penicillium chrysogenum by cup plate method. The extracts were found ...

abstract       background and objective: the spread of drug resistance in bacteria have prompted researchers to seek suitable alternative for antimicrobial drugs among various medicinal plants and nanoparticles. the aim of this study was to evaluate the effect of silver nanoparticles alone and in combination with methanol extract of zataria multiflora on five gram-positive and gram-negative bac...

The antibacterial activities of a number of amide derivatives of penicillin against both penicillin-sensitive and penicillin-resistant cultures were determined. Several of them were found to possess significant inhibitory activity against certain gram-positive bacteria. The amides, although resistant to the destructive action of beta-lactamase, did not protect G in competitive experiments. One ...