56 research outputs found

    The reactivity of lattice nitrogen within the Ni2Mo3N and NiCoMo3N phases

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    In this study, the reactivity of bulk lattice nitrogen within the filled β-Mn structured Ni2Mo3N phase has been investigated by application of powder neutron diffraction and heterolytic nitrogen isotopic exchange measurements. In contrast to Co3Mo3N, despite the similarity in the N immediate local environment comprising NMo6 octahedra, its reactivity is found to be limited and this lower reactivity was maintained upon the introduction of a significant proportion of cobalt to yield its filled β-Mn structured CoNiMo3N quaternary nitride counterpart

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

    Chemical Analysis, Antioxidant, Antimicrobial and Enzyme Inhibitory Effects of Daucus Virgatus (Poir.) Maire Essential oil from Algeria

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    Essential oils (EO) represent an important source of bioactive molecules and are widely used for their great efficacy relating to their different therapeutic properties. The present study aims to contribute to the valorization of Daucus virgatus (Poir.) Maire, an aromatic and native plant spontaneously growing in the North-Eastern regions of Algeria, by analyzing the chemical composition of its essential oil and evaluating the antioxidant and antimicrobial activities, together with the assay of the enzyme inhibitory effects against alpha-glucosidase and cholinesterase. Daucus virgatus EO was extracted by hydrodistillation and analyzed by gas chromatography-mass spectroscometry analysis (GC-MS). Twenty-one constituents accounting for 98% of the whole components were identified. beta-Pinene (77.9%) and alpha-pinene (7.6%) were the most abundant components. The antimicrobial activity against the pathogen microorganisms Listeria innocua, Salmonella typhimurium, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, Escherichia coli and Candida albicans was investigated. The best antimicrobial effect was observed against S. typhimurium and C. albicans, which showed high sensitivity, with inhibition zones ranging between 27.3 and 25 mm; the minimum inhibitory concentrations were 15.63 and 31.25 mu g ml(-1), respectively. In the DPPH test, the essential oil showed a moderate antioxidant effect, with an IC50 value of 39.61 mg ml(-1). D. virgatus EO exhibited an interesting inhibitory effect against alpha-glucosidase enzyme (IC50 = 0.35 mg ml(-1)) compared with the positive control Acarbose (IC50 = 0.24 mg ml(-1)), and a moderate inhibitory effect against cholinesterases enzymes, with IC50 values of 0.33 and 0.20 mg ml(-1) for acetylcholinesterase and butyrylcholinesterase, respectively. D. virgatus EO might be used as a promising source of natural products with potential antimicrobial, antihyperglycemic and anti-Alzheimer effects

    In silico drug discovery of Acetylcholinesterase and Butyrylcholinesterase enzymes inhibitors based on Quantitative Structure-Activity Relationship (QSAR) and drug-likeness evaluation

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    In the last years, in order to achieve a better treatment of Alzheimer's disease (AD), much focus has been put on the development of cholinesterase (Acetylcholinesterase and Butyrylcholinesterase) inhibitor drugs. Thus, the aim of this study is to discover promising active compounds for Acetylcholinesterase and Butyrylcholinesterase enzymes inhibitors based on QSAR model and drug-likeness evaluation. In this study, a series of DL0410 and its 50 derivatives are accounted for the set up of two QSAR models. This allows an exploration of the main molecular descriptors that control the inhibitory activity of specific compounds towards cholinesterase enzymes: Acetylcholinesterase (AChE) and Butyrylcholinesterase (BuChE). Simultanerously, the models can help to predict the inhibitory activity of new compounds within its applicability domain. A Multiple Linear Regression (MLR) analysis is carried out to derive QSAR models. The results indicate that the QSAR models of Acetylcholinesterase and Butyrylcholinesterase inhibitory activity are robust and have a very good prediction capacity, testified by values of R2 equal to 0.935 and 0.895, respectively. The analysis carried out by adopting the QSAR models succeed in screening 15 potential compounds with higher biological activity. Subsequently, the investigated compounds has been subjected to the drug-likeness evaluation and reactivity study. The results show that most of the compounds do not present any bioavailability problem when administered orally. The results also allow determining the compounds that have not clearance problems, those that are the most stable and the most reactive among those tested. These findings indicate that the newly designed candidate drugs have promising potential toward AChE and BuChE enzyme inhibition and should be experimentally investigated
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