2,027 research outputs found

    Antibiotic resistance spread potential in urban wastewater effluents disinfected by UV/H2O2 process

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    Urban wastewater treatment plants (UWTPs) are among the main hotspots of antibiotic resistance (AR) spread into the environment and the role of conventional and new disinfection processes as possible barrier to minimise the risk for AR transfer is presently under investigation. Accordingly, the aim of this work was to evaluate the effect of an advanced oxidation process (AOP) (specifically UV/H2O2) on AR transfer potential. UV/H2O2 disinfection experiments were carried out on real wastewater samples to evaluate the: i) inactivation of total coliforms, Escherichia coli and antibiotic resistant E. coli as well as ii) possible removal of target antibiotic resistance genes (ARGs) (namely, blaTEM, qnrS and tetW). In particular, DNA was extracted from both antibiotic resistant E. coli bacterial cells (intracellular DNA), grown on selective culture media, and the whole water suspension (total DNA) collected at different treatment times. Polymerase chain reaction (PCR) assay was performed to detect the absence/presence of the selected ARGs. Real Time quantitative Polymerase Chain Reaction (qPCR) was used to quantify the investigated ARGs in terms of copiesmL(-1). In spite of the bacterial inactivation and a decrease of ARGs in intracellular DNA after 60min treatment, UV/H2O2 process was not effective in ARGs removal from water suspension (total DNA). Particularly, an increase up to 3.7×10(3)copiesmL(-1) (p>0.05) of blaTEM gene was observed in total DNA after 240min treatment, while no difference (p>0.05) was found for qnrS gene between the initial (5.1×10(4)copiesmL(-1)) and the final sample (4.3×10(4)copiesmL(-1)). On the base of the achieved results, the investigated disinfection process may not be effective in minimising AR spread potential into the environment. The death of bacterial cells, which results in DNA release in the treated water, may pose a risk for AR transfer to other bacteria present in the receiving water body

    Fine-Structure Map of the Histidine Transport Genes in \u3cem\u3eSalmonella typhimurium\u3c/em\u3e

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    Afine-structure genetic map of the histidine transport region of the Salmonella typhimurium chromosome was constructed. Twenty-five deletion mutants were isolated and used for dividing the hisJ and hisP genes into 8 and 13 regions respectively. A total of 308 mutations, spontaneous and mutagen induced, have been placed in these regions by deletion mapping. The histidine transport operon is presumed to be constituted of genes dhuA, hisJ, and hisP, and the regulation of the hosP and hisJ genes by dhuA is discussed. The orientation of this operon relative to purF has been established by three-point crosses as being: purF duhA hisJ hisP

    Urban wastewater disinfection for agricultural reuse: Effect of solar driven AOPs in the inactivation of a multidrug resistant E. coli strain

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    The occurrence of antibiotics in urban wastewater treatment plants (UWTPs) may result in the development of antibiotic resistance and subsequently in the release of multidrug resistant bacteria (MDR) and genes into the effluent. Conventional disinfection processes are only partially effective in controlling ARB spread, so advanced oxidation processes (AOPs) have been investigated as alternative option in this work. In particular, the aim of this work was to comparatively assess the efficiency of solar disinfection and solar driven AOPs (namely H2O2/sunlight, TiO2/sunlight, H2O2/TiO2/sunlight, natural photo-Fenton) for the inactivation of a multidrug (namely ampicillin, ciprofloxacin and tetracycline) resistant E. coli strain isolated from the effluent of the biological process of an UWTP. Different concentrations of H2O2 (0.588–1.470–2.205 mM), TiO2 (50–100 mg L−1), H2O2/TiO2 (0.147 mM/50 mg L−1, 0.588 mM/100 mg L−1) and Fe2+/H2O2 (0.090/0.294, 0.179/0.588, 0.358/1.176 mM) were evaluated at pilot-scale (in compound parabolic collector reactor) in real biologically treated wastewater. All investigated processes resulted in a complete inactivation (5-log decrease) of bacteria until detection limit, but the best disinfection efficiency in terms of treatment time (20 min to reach the detection limit) and required energy (0.98 kJ L−1) was observed for photo-Fenton at pH 4 (Fe2+/H2O2:0.090/0.294 mM). Antimicrobial susceptibility was tested by Kirby-Bauer disk diffusion method. Ampicillin and ciprofloxacin (to which the selected strain is resistant), cefuroxime and nitrofurantoin were chosen as tested antibiotics. None of the investigated processes affected antibiotic resistance of survived colonies

    Embodied simulation and ambiguous stimuli: The role of the mirror neuron system

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    According to the "embodied simulation theory," exposure to certain visual stimuli would automatically trigger action simulation in the mind of the observer, thereby originating a "feeling of movement" modulated by the mirror neuron system (MNS). Grounded on this conceptualization, some of us recently suggested that when exposed to the Rorschach inkblots, in order to see a human movement (e.g., "a person running") in those ambiguous stimuli, the observer would need to experience a "feeling of movement" via embodied simulation. The current study used repetitive transcranial magnetic stimulation (rTMS) to further test this hypothesis. Specifically, we investigated whether temporarily interfering with the activity of the left inferior frontal gyrus (LIFG; a putative MNS area) using rTMS would decrease the propensity to see human movement (M) in the Rorschach inkblots. Thirty-six participants were exposed to the Rorschach stimuli twice, i.e., during a baseline (without rTMS) and soon after inhibitory rTMS. As for the rTMS condition, half of the sample was stimulated over the LIFG (experimental group) and the other half over the Vertex (control group). In line with our hypothesis, the application of rTMS over LIFG, but not over Vertex, yielded a statistically significant reduction in the attribution of M to the ambiguous stimuli, with large effect size. These findings may be interpreted as being consistent with the hypothesis that there is a link between the MNS and the "feeling of movement" people may experience, when observing ambiguous stimuli such as the Rorschach cards

    Effects of Hypericum perforatum on turning behavior in an animal model of Parkinson's disease

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    A Doença de Parkinson é uma doença neurodegenerativa relacionada à idade, caracterizada pela morte lenta e progressiva de neurônios dopaminérgicos da substância negra pars compacta. O Hypericum perforatum (H. perforatum) é um fitoterápico utilizado como antidepressivo, apresentando propriedades antioxidantes, anti-inflamatórias e nootrópicas. Neste trabalho, avaliaram-se os efeitos do tratamento com H. perforatum no comportamento rotatório de ratos no modelo da doença de Parkinson induzido pela administração unilateral de 6-OHDA no feixe prosencefálico medial. Ratos Wistar machos foram tratados com H. perforatum (100, 200 ou 400 mg/kg, v.o.) por 35 dias (do 28º dia antes até o 7º dia após a lesão). As rotações ipsilaterais e contralaterais à lesão foram registradas no 7º, 14º e 21º dias após a cirurgia. As três doses de H. perforatum utilizadas reduziram o número de rotações contralaterais, indicando um possível efeito neuroprotetor da planta. Porém, o H. perforatum não impediu a redução na expressão da enzima tirosina hidroxilase no estriado lesionado, quantificada por Western blot. Propomos que o H. perforatum possa bloquear o aumento da expressão dos receptores dopaminérgicos no estriado lesionado com 6-OHDA. Entretanto, estudos adicionais são necessários para identificar o mecanismo exato pelo qual o H. perforatum reduziu o número de rotações contralaterais. Os resultados do presente estudo sugerem o H. perforatum como um potencial agente terapêutico para a doença de Parkinson.Parkinson's disease (PD) is an age-related neurodegenerative disorder characterized by the slow and progressive death of dopaminergic neurons in the (substantia nigra pars compact). Hypericum perforatum (H. perforatum) is a plant widely used as an antidepressant, that also presents antioxidant and anti-inflammatory properties. We evaluated the effects of H. perforatum on the turning behavior of rats submitted to a unilateral administration of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle as an animal model of PD. The animals were treated with H. perforatum (100, 200, or 400 mg/kg, v.o.) for 35 consecutive days (from the 28th day before surgery to the 7th day after). The turning behavior was evaluated at 7, 14 and 21 days after the surgery, and the turnings were counted as contralateral or ipsilateral to the lesion side. All tested doses significantly reduced the number of contralateral turns in all days of evaluation, suggesting a neuroprotective effect. However, they were not able to prevent the 6-OHDA-induced decrease of tyrosine hydroxylase expression in the lesioned striatum. We propose that H. perforatum may counteract the overexpression of dopamine receptors on the lesioned striatum as a possible mechanism for this effect. The present findings provide new evidence that H. perforatum may represent a promising therapeutic tool for PD

    Distribution pattern of hepatitis C virus genotypes and correlation with viral load and risk factors in chronic positive patients.

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    Objective: Hepatitis C virus (HCV) has emerged as a leading cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma worldwide. The purpose of this study was to describe the distribution pattern of HCV genotypes in chronic hepatitis patients in the Campania region of southern Italy and estimate their association with risk factors and viral load. Materials and Methods: 404 consecutive HCV ribonucleic acid-positive patients were included in the study. HCV genotyping was carried out by the HCV line probe assay test and viral load estimation by the TaqMan real-time PCR system. Results: The predominant genotype was 1 (63.6%), followed by genotype 2 (29.4%), 3 (6.2%) and 4 (0.8%). Subtype 1b was more frequent in females than in males. Conversely, genotype 3 was more frequent in males. No significant difference was observed in age distribution of HCV genotypes. Surgery and dental therapy were the most frequent risk factors for genotype 1 and intravenous drug abuse and tattooing for genotype 3. Patients with genotype 1 more frequently showed high HCV viral load when compared to those with genotypes 2 and 3. Conclusion: The present study revealed that HCV genotypes 1 and 2 accounted for over 95% of all HCV infections in the Campania region, and genotype 1 was more frequently associated with a higher viral load when compared to genotypes 2 and 3

    Prevalência e preditores do uso incorreto dos dispositivos inalatórios em pacientes portadores de Doença Pulmonar Obstrutiva Crônica Prevalence and predictors of incorrect use of inhaler devices in patients with COPD

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    Objetivo: Inferir a prevalência e preditores do uso incorreto dos dispositivos inalatórios em pacientes ambulatoriais portadores de doença pulmonar obstrutiva crônica (DPOC). Métodos: Foi realizado um estudo de corte transversal em pacientes portadores de DPOC atendidos no Ambulatório Central em Anápolis - Goiás. Resultados: A prevalência de indivíduos com uso incorreto do dispositivo de inalação foi de 96% (24 indivíduos). Observou-se que a média de erro entre o grupo que usava um dispositivo era significativamente menor que a do grupo que usava três dispositivos (p=0,04). Foi encontrada correlação negativa entre o número de erros e o VEF1 pós BD em litros (r=0,55; p=0,004), e uma regressão linear mostrou que o número de erros pode ser previsto pelo VEF1 pós BD em litros (p=0,004), que está inversamente relacionado ao número de erros ao usar o dispositivo. Conclusão: Conclui-se que o número de dispositivos inalatórios e a gravidade da doença respiratória são preditores do uso incorreto de dispositivos inalatórios em pacientes com DPOC

    Long non-coding RNA containing ultraconserved genomic region 8 promotes bladder cancer tumorigenesis

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    Ultraconserved regions (UCRs) have been shown to originate non-coding RNA transcripts (T-UCRs) that have different expression profiles and play functional roles in the pathophysiology of multiple cancers. The relevance of these functions to the pathogenesis of bladder cancer (BlCa) is speculative. To elucidate this relevance, we first used genome-wide profiling to evaluate the expression of T-UCRs in BlCa tissues. Analysis of two datasets comprising normal bladder tissues and BlCa specimens with a custom T-UCR microarray identified ultraconserved RNA (uc.) 8+ as the most upregulated T-UCR in BlCa tissues, although its expression was lower than in pericancerous bladder tissues. These results were confirmed on BlCa tissues by real-time PCR and by in situ hybridization. Although uc.8+ is located within intron 1 of CASZ1, a zinc-finger transcription factor, the transcribed non-coding RNA encoding uc.8+ is expressed independently of CASZ1. In vitro experiments evaluating the effects of uc.8+ silencing, showed significantly decreased capacities for cancer cell invasion, migration, and proliferation. From this, we proposed and validated a model of interaction in which uc.8+ shuttles from the nucleus to the cytoplasm of BlCa cells, interacts with microRNA (miR)-596, and cooperates in the promotion and development of BlCa. Using computational analysis, we investigated the miR-binding domain accessibility, as determined by base-pairing interactions within the uc.8+ predicted secondary structure, RNA binding affinity, and RNA species abundance in bladder tissues and showed that uc.8+ is a natural decoy for miR-596. Thus uc.8+ upregulation results in increased expression of MMP9, increasing the invasive potential of BlCa cells. These interactions between evolutionarily conserved regions of DNA suggest that natural selection has preserved this potentially regulatory layer that uses RNA to modulate miR levels, opening up the possibility for development of useful markers for early diagnosis and prognosis as well as for development of new RNA-based cancer therapies
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