- Antibiotic resistance along an urban river impacted by treated wastewaters. [Journal Article]
- STSci Total Environ 2018 Feb 13; 628-629:453-466
- Urban rivers are impacted ecosystems which may play an important role as reservoirs for antibiotic-resistant (AR) bacteria. The main objective of this study was to describe the prevalence of antibiot...
Urban rivers are impacted ecosystems which may play an important role as reservoirs for antibiotic-resistant (AR) bacteria. The main objective of this study was to describe the prevalence of antibiotic resistance along a sewage-polluted urban river. Seven sites along the Zenne River (Belgium) were selected to study the prevalence of AR Escherichia coli and freshwater bacteria over a 1-year period. Culture-dependent methods were used to estimate E. coli and heterotrophic bacteria resistant to amoxicillin, sulfamethoxazole, nalidixic acid and tetracycline. The concentrations of these four antibiotics have been quantified in the studied river. The antibiotic resistance genes (ARGs), sul1, sul2, tetW, tetO, blaTEM and qnrS were also quantified in both particle-attached (PAB) and free-living (FLB) bacteria. Our results showed an effect of treated wastewaters release on the spread of antibiotic resistance along the river. Although an increase in the abundance of both AR E. coli and resistant heterotrophic bacteria was observed from upstream to downstream sites, the differences were only significant for AR E. coli. A significant positive regression was also found between AR E. coli and resistant heterotrophic bacteria. The concentration of ARGs increased from upstream to downstream sites for both particle-attached (PAB) and free-living bacteria (FLB). Particularly, a significant increase in the abundance of four among six ARGs analyzed was observed after crossing urban area. Although concentrations of tetracycline significantly correlated with tetracycline resistance genes, the antibiotic levels were likely too low to explain this correlation. The analysis of ARGs in different fractions revealed a significantly higher abundance in PAB compared to FLB for tetO and sul2 genes. This study demonstrated that urban activities may increase the spread of antibiotic resistance even in an already impacted river.
- Primary antibiotic resistance and its relationship with cagA and vacA genes in Helicobacter pylori isolates from Algerian patients. [Journal Article]
- BJBraz J Microbiol 2018 Feb 13
- The epidemiology of Helicobacter pylori resistance to antibiotics is poorly documented in Africa and especially in Algeria. The aim of our study was to determine the antibiotic resistance rates, as w...
The epidemiology of Helicobacter pylori resistance to antibiotics is poorly documented in Africa and especially in Algeria. The aim of our study was to determine the antibiotic resistance rates, as well as its possible relationship with VacA and CagA virulence markers of isolates from Algerian patients. One hundred and fifty one H. pylori isolate were obtained between 2012 and 2015 from 200 patients with upper abdominal pain. Antimicrobial susceptibility testing was performed for amoxicillin, clarithromycin, metronidazole, ciprofloxacin, rifampicin and tetracycline. Molecular identification of H. pylori and the detection of vacA and cagA genes were performed using specific primers. We found that H. pylori was present in 83.5% of collected biopsies, 54.9% of the samples were cagA positive, 49.67% were vacA s1m1, 18.30% were vacA s1m2 and 25.49% were vacA s2m2. Isolates were characterized by no resistance to amoxicillin (0%), tetracycline (0%), rifampicin (0%), a high rate of resistance to metronidazole (61.1%) and a lower rate of resistance to clarithromycin (22.8%) and ciprofloxacin (16.8%). No statically significant relationship was found between vagA and cagA genotypes and antibiotic resistance results (p>0.5) except for the metronidazole, which had relation with the presence of cagA genotype (p=0.001).
- Study of pandrug and heavy metal resistance among E. coli from anthropogenically influenced Delhi stretch of river Yamuna. [Journal Article]
- BJBraz J Microbiol 2018 Feb 12
- Escalating burden of antibiotic resistance that has reached new heights present a grave concern to mankind. As the problem is no longer confined to clinics, we hereby report identification of a pandr...
Escalating burden of antibiotic resistance that has reached new heights present a grave concern to mankind. As the problem is no longer confined to clinics, we hereby report identification of a pandrug resistant Escherichia coli isolate from heavily polluted Delhi stretch of river Yamuna, India. E. coli MRC11 was found sensitive only to tobramycin against 21 antibiotics tested, with minimum inhibitory concentration values >256μg/mL for amoxicillin, carbenicillin, aztreonam, ceftazidime and cefotaxime. Addition of certain heavy metals at higher concentrations were ineffective in increasing susceptibility of E. coli MRC11 to antibiotics. Withstanding sub-optimal concentration of cefotaxime (10μg/mL) and mercuric chloride (2μg/mL), and also resistance to their combinatorial use, indicates better adaptability in heavily polluted environment through clustering and expression of resistance genes. Interestingly, E. coli MRC11 harbours two different variants of blaTEM (blaTEM-116 and blaTEM-1 with and without extended-spectrum activity, respectively), in addition to mer operon (merB, merP and merT) genes. Studies employing conjugation, confirmed localization of blaTEM-116, merP and merT genes on the conjugative plasmid. Understanding potentialities of such isolates will help in determining risk factors attributing pandrug resistance and strengthening strategic development of new and effective antimicrobial agents.
- The prevalence and antimicrobial resistance of Listeria spp in raw milk and traditional dairy products delivered in Yazd, central Iran (2016). [Journal Article]
- FCFood Chem Toxicol 2018 Feb 12
- Listeria monocytogenes is an important foodborne pathogen which its data in Iranian dairy products is limited. A total of 545 samples of traditional dairy products (raw milk, traditional cheese, trad...
Listeria monocytogenes is an important foodborne pathogen which its data in Iranian dairy products is limited. A total of 545 samples of traditional dairy products (raw milk, traditional cheese, traditional butter, traditional curd, and traditional ice cream) were collected from traditional dairy shops located in Yazd, Iran. L. monocytogenes was isolated, and positive samples were confirmed by polymerase chain reaction. Antibiotic sensitivity test was conducted to determine the antibiotic resistance. Listeria species were isolated from 11.7% samples. 4.03% samples were identified as L. monocytogenes, 5.6% as L. innocua, 1.8% as L. seeligeri, and 0.18% L. murrayi. All L. monocytogenes isolates were resistant to tetracycline, chloramphenicol, penicillin, and amoxicillin/clavulanic acid. Consumption of raw milk and its traditional products prepared inadequate heat treatment and the lack of appropriate control measures might lead to serious health problems. As our results show, the Iranian food safety authorities should set up an effective standard to screen all susceptible food for the presence of Listeria spp.
- Microbiology and antibiotic therapy of subperiosteal orbital abscess in children with acute ethmoiditis. [Journal Article]
- IJInt J Pediatr Otorhinolaryngol 2018; 106:91-95
- CONCLUSIONS: For five years Streptococcus milleri, Staphylococcus spp and anaerobic bacteria are on the rise in acute ethmoiditis complicated by SPOA. That is why antibiotics must be adapted to these bacteria even in children under ten years old.
- Antimicrobial Prophylaxis with Combat-Related Open Soft-Tissue Injuries. [Journal Article]
- MMMil Med 2018 Feb 13
- CONCLUSIONS: Use of non-guideline directed EGN-based post-trauma antibiotic prophylaxis does not improve infectious outcomes nor does it shorten hospital stay.
- Amine-Functionalized Al-MOF#@yxSm2O3-ZnO: A Visible Light-Driven Nanocomposite with Excellent Photocatalytic Activity for the Photo-Degradation of Amoxicillin. [Journal Article]
- ICInorg Chem 2018 Feb 15
- A visible light-driven amine-functionalized Al-based MOF#@yxSm2O3-ZnO nanocomposite (NH2-MOF#@yxSm2O3-ZnO NCP) was synthesized as an effective photocatalyst for AMX degradation in the presence of ult...
A visible light-driven amine-functionalized Al-based MOF#@yxSm2O3-ZnO nanocomposite (NH2-MOF#@yxSm2O3-ZnO NCP) was synthesized as an effective photocatalyst for AMX degradation in the presence of ultrasound, in which # is MOF synthesis conditions from MOFIto MOFXIIand x and y stand for the weight percentages of Sm2O3-to-ZnO and Sm2O3-ZnO-to-MOF, respectively. The β-lactam antibiotic AMX, which is widely used for treating Gram-positive and Gram-negative bacterial infections in both animals and humans, was employed as a model pollutant. Using different detection techniques, the synthesized materials were characterized. Furthermore, effects of different synthesis methods, ultrasonic time, precursor concentration, sonication amplitude, and modulators on the MOFs photocatalytic behavior were taken into account. Also, catalytic dose and recycling, H2O2usage, and operating pH effects were investigated. Compared to the pure forms of NH2-MOF-53(Al) and Sm2O3-ZnO, the NCPs having the optimal Sm2O3-ZnO and NH2-MOF-53(Al) contents highly influenced the photocatalytic activity due to the synergetic impacts of the high charge mobility and the red shift in the NH2-MOF@Sm2O3-ZnO NCPs absorption edge compared to the Sm2O3-ZnO nanoflowers. We used a TOC analyzer, UV/vis spectroscopy, and HPLC chromatogram to estimate the rate of AMX elimination in water over NH2-MOFXII@307Sm2O3-ZnO NCPs as our optimal sample. In addition, after the AMX pollutant degradation, the NH2-MOF@Sm2O3-ZnO NCPs were structurally stable and maintained the majority of their photocatalytic properties even after five runs of recycling process The NH2-MOFXII@307Sm2O3-ZnO NCPs as the superior photocatalysts were more examined and a mechanism for the AMX degradation was suggested. As a suggestion, our obtained results can be used as a starting point for the preparation of the other heterogeneous MOF-based NCPs combined with the Sm2O3-ZnO for a variety of applications such as the environmental remediation.
- Normal boundary intersection applied as multivariate and multiobjective optimization in the treatment of amoxicillin synthetic solution. [Journal Article]
- EMEnviron Monit Assess 2018 Feb 14; 190(3):140
- Amoxicillin is a useful antibiotic to combat bacterial infections. However, this drug can cause serious problems when discarded in waterways due to its great bioaccumulation potential. This compound ...
Amoxicillin is a useful antibiotic to combat bacterial infections. However, this drug can cause serious problems when discarded in waterways due to its great bioaccumulation potential. This compound can be treated via advanced oxidation processes (AOPs), which are capable of converting amoxicillin into carbon dioxide and water. In this context, the use of ozone as an oxidizer has excelled in amoxicillin degradation. This paper aims at treating a synthetic solution of amoxicillin (0.1 g L-1) in a reactor with ozone bubbling. A Design of Experiment (DoE) with a response surface known as Central Composite Design (CCD) was used to optimize the treatment process. In addition, a Normal Boundary Intersection (NBI) method was used in the construction of a Pareto boundary chart. Results after 1-h treatment showed a reduction of 53% of the initial organic matter from a designed model using factors, such as pH, ozone generator power, and O3flow. A model was built from the CCD with score of 0.9929. Thus, the model was able to represent the real scenario with confidence.
- Application and evaluation of a high-resolution mass spectrometry screening method for veterinary drug residues in incurred fish and imported aquaculture samples. [Journal Article]
- ABAnal Bioanal Chem 2018 Feb 14
- The ability to detect chemical contaminants, including veterinary drug residues in animal products such as fish, is an important example of food safety analysis. In this paper, a liquid chromatograph...
The ability to detect chemical contaminants, including veterinary drug residues in animal products such as fish, is an important example of food safety analysis. In this paper, a liquid chromatography high-resolution mass spectrometry (LC-HRMS) screening method using a quadrupole-Orbitrap instrument was applied to the analysis of veterinary drug residues in incurred tissues from aquacultured channel catfish, rainbow trout, and Atlantic salmon and imported aquacultured products including European eel, yellow croaker, and tilapia. Compared to traditional MS methods, the use of HRMS with nontargeted data acquisition and exact mass measurement capability greatly increased the scope of compounds that could be monitored simultaneously. The fish samples were prepared for analysis using a simple efficient procedure that consisted of an acidic acetonitrile extraction followed by solid phase extraction cleanup. Two different HRMS acquisition programs were used to analyze the fish extracts. This method detected and identified veterinary drugs including quinolones, fluoroquinolones, avermectins, dyes, and aminopenicillins at residue levels in fish that had been dosed with those compounds. A metabolite of amoxicillin, amoxicillin diketone, was also found at high levels in catfish, trout, and salmon. The method was also used to characterize drug residues in imported fish. In addition to confirming findings of fluoroquinolone and sulfonamide residues that were found by traditional targeted MS methods, several new compounds including 2-amino mebendazole in eel and ofloxacin in croaker were detected and identified. Graphical Abstract Aquacultured samples are analyzed with a high-resolution mass spectrometry screening method to detect and identify unusual veterinary drug residues including ofloxacin in an imported fish.
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- Leech management before application on patient: a nationwide survey of practices in French university hospitals. [Journal Article]
- ARAntimicrob Resist Infect Control 2018; 7:19
- CONCLUSIONS: Measures to prevent infectious complications before application to patient have to be better applied and guidelines of good practices are necessary.