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AIMS: In this study, the association between multidrug resistance (MDR) and the expression of some virulence factors were evaluated in Escherichia coli strains isolated from infant faeces and fresh green vegetables. The effect of isolate origin on associated virulence factors was evaluated. In addition, genetic fingerprinting of a sample of these isolates (10 isolates from each group) was studied in order to detect any genetic relatedness among these isolates. METHODS AND RESULTS: Escherichia coli isolates were divided into four groups based on their origin (human faeces or plant) and their antibiotic resistance (multiresistance or susceptible). PCR was used to investigate heat-labile and heat-stable enterotoxin genes, and four siderophore genes (aerobactin, enterobactin, salmochelin and yersiniabactin). Genetic fingerprinting of the isolates was performed using enterobacterial repetitive intergenic consensus PCR. Siderophore production was measured by a colorimetric method. Biofilm formation was evaluated by a crystal violet assay. The results of the study showed that the expression of MDR is not significantly associated with an increase in these virulence factors or with biofilm formation. However, the origin of isolates had a significant association with siderophore gene availability and consequently on the concentrations of siderophores released. Genetic fingerprinting indicated that human and plant isolates have the same clonal origin, suggesting their circulation among humans and plants. CONCLUSION: Antibiotic-susceptible strains of E. coli may be as virulent as MDR strains. Results also suggest that the environment can play a potential role in selection of strains with specific virulence factors. SIGNIFICANCE AND IMPACT OF THE STUDY: Antibiotic-susceptible isolates of Escherichia coli from plant or human origin can be as virulent as the multidrug resistance (MDR) ones. Genetic relatedness was detected among the isolates of plant and human origin, indicating the circulation of these bacteria among human and plants. This could imply a potential role for environmental antimicrobial resistant bacteria in human infection.

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A simple and inexpensive titrimetric method for the determination of magnesium ion in esomeprazole magnesium raw material was developed and validated according to International Conference on Harmonization guidelines and the United States Pharmacopoeia. The method depends on complex formation between EDTA and magnesium ion. The method was proven to be valid, equivalent and useful as an alternative method to the current pharmacopeial methods that are based on atomic absorption spectrometry.

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The discovery in 1998 that triclosan has a site-specific action in the bacterial cell as an inhibitor of NADH- or NADPH-dependent enoyl-acyl carrier protein reductase led to a lively debate in the scientific press. The thesis of this debate was that such a mode of action may allow triclosan to induce resistance and cross-resistance in bacterial cells. The debate last saw review in 2004, and this paper aims at updating our knowledge in this area, given recent research on the topic.

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AIMS: To investigate the presence of a relationship between the strength of attachment of Pseudomonas aeruginosa to stainless steel surfaces and their observed multiple drug resistance. METHODS AND RESULTS: Multiple drug resistance of clinical and environmental isolates of Ps. aeruginosa was evaluated using disc diffusion method. The blot succession technique was used to quantify the strength of attachment of Ps. aeruginosa isolates. Different multiple drug-resistant Ps. aeruginosa isolates exhibited variable attachment strength. Although the highest multiple drug-resistant clinical isolate was shown to have the least attachment strength among clinical isolates, a weak correlation was found between attachment strength and multiple resistance among our investigated Ps. aeruginosa isolates. CONCLUSIONS: There is a weak correlation between multiple drug resistance and strength of attachment to stainless steel surfaces. SIGNIFICANCE AND IMPACT OF THE STUDY: Even low-resistant Ps. aeruginosa could have the potential of attaching firmly to surfaces and forming biofilm.

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AIMS: The effect of subminimal inhibitory concentrations (sub-MICs) of cefalexin, ciprofloxacin and roxithromycin was investigated on some virulence factors [e.g. coagulase, Toxic Shock Syndrome Toxin 1 (TSST-1) and biofilm formation] expressed by Staphylococcus aureus biofilms. METHODS AND RESULTS: Biofilms were grown with and without the presence of 1/16 MIC of antibiotics on Sorbarod filters. Eluate supernatants were collected, and coagulase and TSST-1 production were evaluated. Coagulase production was reduced in eluates exposed to roxithromycin when compared to control, while TSST-1 production was reduced in biofilms exposed to cefalexin and to a lesser extent, ciprofloxacin. In addition, the ability of Staph. aureus to produce biofilm in microtitre plates in the presence of sub-MIC antibiotics indicated that cefalexin induced biofilm formation at a wide range of sub-MICs. TSST-1 produced from the challenged and control biofilms was purified, and its proliferative activity was studied on single cell suspension of mouse splenocytes using MTS/PMS assay. No significant difference in the activity between the treated toxin and the control has been observed. CONCLUSIONS: Antibiotics at sub-MIC levels interfere with bacterial biofilm virulence expression depending on the type and concentration of antibiotic used. SIGNIFICANCE AND IMPACT OF THE STUDY: The establishment of sub-MICs of antibiotics in clinical situations may result in altered virulence states in pathogenic bacteria.

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We compared axillary and rectal temperatures in 216 patients to assess the reliability of axillary temperature for determining fever in children under 14 years of age. Beyond the neonatal period, the mean rectal temperature was significantly higher than the axillary temperature. The sensitivity of axillary temperature in detecting fever was 87.5% among neonates but only 46% among older children. Axillary temperature correlated well with rectal temperature in neonates but not older children. There was no direct mathematical relationship between axillary and rectal temperature. Axillary temperature should be taken in neonates as it is less hazardous; rectal temperature should be used beyond this age.

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We compared axillary and rectal temperatures in 216 patients to assess the reliability of axillary temperature for determining fever in children under 14 years of age. Beyond the neonatal period, the mean rectal temperature was significantly higher than the axillary temperature. The sensitivity of axillary temperature in detecting fever was 87.5% among neonates but only 46% among older children. Axillary temperature correlated well with rectal temperature in neonates but not older children. There was no direct mathematical relationship between axillary and rectal temperature. Axillary temperature should be taken in neonates as it is less hazardous; rectal temperature should be used beyond this age

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To determine the most useful clinical symptoms and signs for detection of pneumonia in children, we carried out a prospective clinical study at Queen Alia Hospital, Amman, on 147 children admitted between August 2002 and January 2003 with clinical pneumonia. All the children had chest X-rays, which were read by the same radiologist. The most sensitive and specific signs and symptoms for prediction of pneumonia were coughing, tachypnoea (respiratory rate > 50/min) and chest wall indrawing. We found that presence of tachypnoea and lower chest wall indrawing can detect most cases of pneumonia. If all clinical signs are negative, chest X-ray findings are unlikely to be positive.

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To determine the most useful clinical symptoms and signs for detection of pneumonia in children, we carried out a prospective clinical study at Queen Alia Hospital, Amman, on 147 children admitted between August 2002 and January 2003 with clinical pneumonia. All the children had chest X-rays, which were read by the same radiologist. The most sensitive and specific signs and symptoms for prediction of pneumonia were coughing, tachypnoea [respiratory rate > 50/min] and chest wall indrawing. We found that presence of tachypnoea and lower chest wall indrawing can detect most cases of pneumonia. If all clinical signs are negative, chest X-ray findings are unlikely to be positive

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