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BACKGROUND: Antibiotic resistance is a major problem threatening human beings. The genetic determinants that carry resistance genes can be transmitted in several ways in clinical and food environments. Hence, this research study aimed to investigate the presence of New Delhi metallo-beta-lactamase-1 (blaNDM-1) produced by enterotoxigenic Enterobacter cloacae in both clinical and food samples. METHODS AND RESULTS: Twenty-four isolates of Enterobacter spp. were isolated, seven isolates from food samples and 17 isolates from blood taken from neonates and children (1 day - 10 years old) resident in a children's hospital. Antibiotic susceptibility test to 14 antibiotics was performed for all isolates. Enterotoxigenicity of the clinical and foodborne isolates was detected phenotypically using Suckling mouse bioassay. Genomic deoxyribonucleic acid (DNA) was extracted from the isolated Enterobacter spp. that were detected resistant to imipenem. Polymerase chain reaction (PCR) was used to amplify blaNDM-1 gene followed by sequencing. The results of the bioassay revealed that 64.28% of E. cloacae ssp. cloacae isolates were enterotoxigenic. Two E. cloacae ssp. cloacae were imipenem resistant. CONCLUSIONS: This study showed that one isolate from a male child 1 < year was bla NDM-1 positive that was con-firmed by sequencing. This is the first report that revealed blaNDM-1 producing Enterobacter cloacae in Iraq.

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This study was conducted to determine the effects of rice husk ash (RHA) and Fe-coated rice husk ash (Fe-RHA) on the bioavailability and mobility of As, Cd, and Mn in mine tailings. The amendments were added to the tailings at 0, 5, 10, or 20% (w/w) and the mixtures were incubated for 0, 7, 15, 30, 45, and 60 days. The CaCl2 extractable As, Cd, and Mn in the amended tailings were determined at each interval of incubation period. In addition, the tailings mixture was leached with simulated rain water (SRW) every week from 0 day (D 0) until day 60 (D 60). The results showed that both RHA and Fe-RHA application significantly decreased the CaCl2-extractable Cd and Mn but increased that of As in the tailings throughout the incubation period. Consequently, addition of both RHA and Fe-RHA leached out higher amount of As from the tailings but decreased Cd and Mn concentration compared to the controls. The amount of As leached from the Fe-RHA-amended tailings was less than that from RHA-amended tailings. Application of both RHA and Fe-RHA could be an effective way in decreasing the availability of cationic heavy metals (Cd and Mn) in the tailings but these amendments could result in increasing the availability of anionic metalloid (As). Therefore, selection of organic amendments to remediate metal-contaminated tailings must be done with great care because the outcomes might be different among the elements.

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The dopamine transporter (DAT) is the primary molecular target responsible for the rewarding properties of the psychostimulants amphetamine (AMPH) and cocaine. AMPH increases extracellular dopamine (DA) by promoting its nonexocytotic release via DAT-mediated efflux. Previous studies in heterologous cells have shown that phosphorylation of the amino terminus of DAT is required for AMPH-induced DA efflux but not for DA uptake. However, the identity of many of the modulatory proteins and the molecular mechanisms that coordinate efflux and the ensuing behavioral effects remain poorly defined. Here, we establish a robust assay for AMPH-induced hyperlocomotion in Drosophila melanogaster larvae. Using a variety of genetic and pharmacological approaches, we demonstrate that this behavioral response is dependent on DA and on DAT and its phosphorylation. We also show that methylphenidate (MPH), which competitively inhibits DA uptake but does not induce DAT-mediated DA efflux, also leads to DAT-dependent hyperlocomotion, but this response is independent of DAT phosphorylation. Moreover, we demonstrate that the membrane raft protein Flotillin-1 is required for AMPH-induced, but not MPH-induced, hyperlocomotion. These results are the first evidence of a role for a raft protein in an AMPH-mediated behavior. Thus, using our assay we are able to translate molecular and cellular findings to a behavioral level and to differentiate in vivo the distinct mechanisms of two psychostimulants.

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Deforestation leads to the deterioration of soil fertility which occurs rapidly under tropical climates. Forest rehabilitation is one of the approaches to restore soil fertility and increase the productivity of degraded areas. The objective of this study was to evaluate and compare soil biological properties under enrichment planting and secondary forests at Tapah Hill Forest Reserve, Perak after 42 years of planting. Both areas were excessively logged in the 1950s and left idle without any appropriate forest management until 1968 when rehabilitation program was initiated. Six subplots (20 m × 20 m) were established within each enrichment planting (F1) and secondary forest (F2) plots, after which soil was sampled at depths of 0-15 cm (topsoil) and 15-30 cm (subsoil). Results showed that total mean microbial enzymatic activity, as well as biomass C and N content, was significantly higher in F1 compared to F2. The results, despite sample variability, suggest that the rehabilitation program improves the soil biological activities where high rate of soil organic matter, organic C, N, suitable soil acidity range, and abundance of forest litter is believed to be the predisposing factor promoting higher population of microbial in F1 as compared to F2. In conclusion total microbial enzymatic activity, biomass C and biomass N evaluation were higher in enrichment planting plot compared to secondary forest. After 42 years of planting, rehabilitation or enrichment planting helps to restore the productivity of planted forest in terms of biological parameters.

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Euphorbia heterophylla L. (Euphorbiaceae) is a herbaceous species of great economic importance due to its invasive potential and consequent damage to agriculture and pasture land. For the first time, we provide information on its chromosome number, morphology, and behavior of mitotic chromosomes. Seeds were germinated and submitted to four treatments to obtain metaphases: 0.5% colchicine for 2 to 5 h, at ambient temperature; 0.5% colchicine for 16 to 24 h; 0.0029 M 8-hydroxyquinoline (8-HQ) for 2 to 5 h at ambient temperature, and 0.0029 M 8-HQ for 16 to 24 h at 4 degrees C. The material was then fixed in methanol:acetic acid (3:1) and kept at -20 degrees C for 24 h. Roots were macerated in the enzyme solution of Flaxzyme (NOVO FERMENT)-distilled water (1:40) at 34 degrees C for 2 h and later fixed again. Chromosome preparations were obtained by the dissociation of the apical meristems. The best chromosome preparations were obtained with the use of 8-HQ for 21 h 30 min at 4 degrees C. E. heterophylla showed 2n = 28 chromosomes. The short arm of the largest pair of chromosomes of the complement (pair number 1) displayed a secondary constriction while the nucleolus was observed in the interphasic cell. Structural rearrangements were also observed in the E. heterophylla L. genome. The genomic instability associated with polyploidy may be the result of selection shaped by environmental adaptations and/or human-induced manipulation through agricultural practices.

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Euphorbia heterophylla L. (Euphorbiaceae) is a herbaceous species of great economic importance due to its invasive potential and consequent damage to agriculture and pasture land. For the first time, we provide information on its chromosome number, morphology, and behavior of mitotic chromosomes. Seeds were germinated and submitted to four treatments to obtain metaphases: 0.5% colchicine for 2 to 5 h, at ambient temperature; 0.5% colchicine for 16 to 24 h; 0.0029 M 8-hydroxyquinoline (8-HQ) for 2 to 5 h at ambient temperature, and 0.0029 M 8-HQ for 16 to 24 h at 4°C. The material was then fixed in methanol:acetic acid (3:1) and kept at -20°C for 24 h. Roots were macerated in the enzyme solution of Flaxzyme™ (NOVO FERMENT™)-distilled water (1:40) at 34°C for 2 h and later fixed again. Chromosome preparations were obtained by the dissociation of the apical meristems. The best chromosome preparations were obtained with the use of 8-HQ for 21 h 30 min at 4°C. E. heterophylla showed 2n = 28 chromosomes. The short arm of the largest pair of chromosomes of the complement (pair number 1) displayed a secondary constriction while the nucleolus was observed in the interphasic cell. Structural rearrangements were also observed in the E. heterophylla L. genome. The genomic instability associated with polyploidy may be the result of selection shaped by environmental adaptations and/or human-induced manipulation through agricultural practices.

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The in vitro susceptibilities of 75 clinical isolates of Xanthomonas maltophilia to nalidixic acid, five fluoroquinolones, latamoxef, and doxycycline were determined. Spontaneous mutants were selected, at a frequency of about 10(-5) to 10(-7) from four strains by culturing the strains in the presence of each quinolone. Selection in the presence of nalidixic acid provided mutants that were either resistant only to that compound or that exhibited cross-resistance to all the fluoroquinolones tested. Cross-resistance was always observed for mutants selected on any of the five fluoroquinolones. It was always associated with chloramphenicol resistance and, frequently, with doxycycline resistance. The electrophoretic alterations of the outer membrane proteins of the mutants suggest that different mechanisms may be involved in quinolone resistance in X. maltophilia.

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Escherichia coli B41 (O101: K99: F41: ST+) adheres to HeLa 229 cells in a diffuse pattern. Heat-killed (100-105 degrees C) Lactobacillus acidophilus (Lactéol strain) was found to inhibit this adhesion in a dose-dependent manner. This inhibitory action was lost after lysis of the L acidophilus, suggesting steric hindrance of E coli adhesion sites rather than competition for a common binding site. A thermostable factor (100-105 degrees C) excreted by L acidophilus into the medium may be required for the adhesion of L acidophilus to HeLa cells, and for the inhibition of adhesion of E coli to these cells.

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The bacteria of the genre Capnocytophaga are part of the subdominant flora of the oral cavity. For diverse microorganisms it has been proved that the adhesion constitutes the first step of the colonization of a place leading to the eventual pathology. The adhesion capacity to human epithelial cells (keratinised and non) of eight strains of genus Capnocytophaga has been studied. All strains appear to have a very weak capacity of adhesion. This diministe can be originated from the fact that the host cells have been harvested from healthy subjects.

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A prospective open study carried out over 5 years and including 20 patients suffering from chronic bone suppuration following orthopaedic surgery has confirmed the value of the new quinolones (NQ) in these indications. The patients received pefloxacin or ciprofloxacin most often combined with rifampicin or fusidic acid for a mean period of 7 months. Single or multiple organism infections were documented in 14 patients, the majority being Staph. aureus (n = 13) and Pseudomonas (n = 14). Samples were sterile in 6 cases. Fourteen therapeutic successes and 5 failures were observed. In one patient, improvement was noted but the post-treatment follow-up insufficient to pronounce a cure. Success was obtained in 14 out of 16 patients who had sensitive organisms or sterile samples. The mean post-treatment follow-up (16 months) was satisfactory but insufficient to speak of cure. However, in these patients for whom further surgery, however desirable, is often refused, NQ constitute an improvement which raises hopes of cure or allows further surgery.

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Nitroxoline or 5-nitro-8-hydroxyquinoline acts by a chelating effect with various metallic divalent cations. The chelating property of nitroxoline has been proposed as an hypothesis to explain the activity of this drug, at sub-MIC, on the inhibition of bacterial adherence. Nitroxoline (MIC/4) does not inhibit fimbriae synthesis but its antibacterial activity on E. coli 387 (MS/MS) was decreased by the addition of MgCl2 (50 mM) and CaCl2 (10 mM). The chelating effect of nitroxoline is mainly due to the presence of the nitrous radical in position 5. Nitroxoline would act at the outer membrane level of the bacterial cell-wall by a chelating effect preferentially with Mg++ than Ca++. Furthermore, nitroxoline (MIC/8) increases the bacterial surface hydrophobicity of E. coli 38 in contrast to EDTA (MIC/4). The both products inhibit the bacterial adherence to cells with the same manner.

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Nitroxolin or 5-nitro-8-hydroxyquinoline, used in the treatment of acute or recurrent uncomplicated urinary tract infection (UTI), has been investigated to demonstrate inhibitory effect on bacterial adherence to epithelial cells or solid surfaces. Nitroxolin in vitro and in urine inhibits bacterial adherence of E. coli 38 (MS/MS) on HeLa cells and epithelial cells from human bladder mucosa. In the same conditions, norfloxacin has no effect. Nitroxolin (MIC/8) decreases with a statistically significant difference (p less than 0.001) the bacterial attachment to a urinary catheter surface made in siliconated latex. These results justify the performance of a clinical trial in the prophylaxis of recurrent UTI and the outcome of a bacteriuria associated with indwelling or intermittent bladder catheter.

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The present study evaluates the effects of sub-inhibitory concentrations of nitroxoline, (oxyquinoline derivative) widely used in the treatment of uncomplicated, urinary tract infections, on the adherence of uropathogenic strains of Escherichia coli. These bacterial strains showed mannose sensitive and/or mannose resistant hemagglutinating activity (HA). In the presence of nitroxoline and at sub-MIC concentrations, inhibition of adherence is 90% (MIC/4), 87% (MIC/8), and 70% (MIC/16), whatever HA's are expressed by the E. coli strains. The inhibitory effect on adherence is also observed in the urine after oral administration of 400 mg of nitroxoline. The concentrations of nitroxoline in the urine are determined by microbiological assay (anti-bacterial activity) and by physico-chemical assay (total nitroxoline and free nitroxoline). The percentages of inhibition are related to the concentrations of free and conjugated nitroxoline. For a 1/16 dilution of urine, the inhibitory effect is 70% and 87% respectively 1 h 30 and 2 h 30 after oral administration of nitroxoline. After 5 h, a similar inhibitory effect is observed for a 1/2 dilution of urine. These results justify the performance of a clinical trial on the prophylaxis of recurrent urinary tract infections by nitroxoline.

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Aural rehabilitation is a critical and often neglected aspect of a hearing-impaired patient's total rehabilitation. This case description illustrates the need for implementation of aural rehabilitation services. A 59-year-old woman exhibited bilateral profound sensorineural hearing loss following the onset of encephalitis herpes simplex. Auditory amplification attempts were unsuccessful. Aural rehabilitation was initiated immediately, and she was seen for lipreading and vibrotactile stimulation training. Goals progressed from identification of single words within a category to phonemic recognition. Vibrotactile stimulation was used to facilitate environmental awareness. Therapy goals reflected the patient's increased motivation to communicate within her environment. This patient's communicative status is viewed on a continuum: from success in individual treatment goals, extending to successful communication within the structure of the entire rehabilitation setting, and finally to functional communication within her home environment.

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This study was aimed at establishing a baseline for the latency values of the biceps-brachii, triceps-brachii and brachioradialis tendon reflexes from the moment of elicitation by percussion of the tendon, to the appearance of the muscle action potential. The percussion hammer triggered the electronic sweep on the electromyograph oscilloscope, showing latency to the onset of the potential. Standard skin electrodes were used. Certain precautions were taken to avoid artifacts caused by skin movement. Thirty normal volunteer subjects, between the ages of 17 and 55 years, were examined. Biceps reflex latency values varied between 9 and 14 msec; with a mode of 11 msec and an average of 11 msec. Triceps latency values varied between 9 and 13 msec; with a mode of 11 msec and an average of 10 msec, and brachioradialis latency values varied between 13 and 20 msec, with a mode of 16 msec and an average of 16 msec.

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