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Background Bedaquiline is a core drug for the treatment of multidrug-resistant tuberculosis; however, the understanding of resistance mechanisms is poor, which is hampering rapid molecular diagnostics. Some bedaquiline-resistant mutants are also cross-resistant to clofazimine. To decipher bedaquiline and clofazimine resistance determinants, we combined experimental evolution, protein modelling, genome sequencing, and phenotypic data. Methods For this in-vitro and in-silico data analysis, we used a novel in-vitro evolutionary model using subinhibitory drug concentrations to select bedaquiline-resistant and clofazimine-resistant mutants. We determined bedaquiline and clofazimine minimum inhibitory concentrations and did Illumina and PacBio sequencing to characterise selected mutants and establish a mutation catalogue. This catalogue also includes phenotypic and genotypic data of a global collection of more than 14 000 clinical Mycobacterium tuberculosis complex isolates, and publicly available data. We investigated variants implicated in bedaquiline resistance by protein modelling and dynamic simulations. Findings We discerned 265 genomic variants implicated in bedaquiline resistance, with 250 (94%) variants affecting the transcriptional repressor (Rv0678) of the MmpS5–MmpL5 efflux system. We identified 40 new variants in vitro, and a new bedaquiline resistance mechanism caused by a large-scale genomic rearrangement. Additionally, we identified in vitro 15 (7%) of 208 mutations found in clinical bedaquiline-resistant isolates. From our in-vitro work, we detected 14 (16%) of 88 mutations so far identified as being associated with clofazimine resistance and also seen in clinically resistant strains, and catalogued 35 new mutations. Structural modelling of Rv0678 showed four major mechanisms of bedaquiline resistance: impaired DNA binding, reduction in protein stability, disruption of protein dimerisation, and alteration in affinity for its fatty acid ligand. Interpretation Our findings advance the understanding of drug resistance mechanisms in M tuberculosis complex strains. We have established an extended mutation catalogue, comprising variants implicated in resistance and susceptibility to bedaquiline and clofazimine. Our data emphasise that genotypic testing can delineate clinical isolates with borderline phenotypes, which is essential for the design of effective treatments. Funding Leibniz ScienceCampus Evolutionary Medicine of the Lung, Deutsche Forschungsgemeinschaft, Research Training Group 2501 TransEvo, Rhodes Trust, Stanford University Medical Scientist Training Program, National Institute for Health and Care Research Oxford Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust, Bill & Melinda Gates Foundation, Wellcome Trust, and Marie Skłodowska-Curie Actions.

The increase in multidrug-resistant bacteria has reached an alarming rate globally, making it necessary to understand the underlying mechanisms mediating resistance in order to discover new therapeutics. Tigecycline (TGC) is a last-resort antimicrobial agent for the treatment of serious infections caused by extensively drug-resistant Enterobacteriaceae.The TGC-resistant Escherichia coli mutants were obtained by exposing three different TGC-susceptible isolates belonging to ST131 (n = 2) and ST405 (n = 1) to increasing concentrations of TGC. The genetic alterations associated with reduced susceptibility to TGC were identified using whole genome sequencing. The fitness cost of TGC resistance acquisition, as well as incidence of cross-resistance, was also investigated.The TGC minimum inhibitory concentrations (MICs) of in vitro selected mutants were elevated 8 to 32 times compared with ancestral strains. Inactivating mutations (frameshift and nonsense) or amino acid substitutions were identified in genes encoding proteins with diverse functions, including AcrAB efflux pump or its regulators (lon and marR), Lipopolysaccharides (LPS) inner core biosynthesis enzymes (waaQ and eptB), ribosomal S9 protein (rpsI), and RNA polymerase β subunit. In most cases (but not all), acquisition of TGC resistance was associated with a fitness cost. While TGC resistance development was associated with cross-resistance to other members of the tetracycline family and chloramphenicol, hypersensitivity to nitrofurantoin was identified among heptose III-less LPS mutants.TGC resistance among the studied mutants was found to be multifactorial with extrusion by efflux transports being the most common mechanism. The LPS inner core biosynthesis pathway, as well as ribosomal S9 protein, could be additional targets for TGC resistance.

9 páginas, 4 figuras, 1 tabla., Background: Molecular diagnostics are considered the most promising route to achieving rapid, universal drug susceptibility testing for Mycobacterium tuberculosiscomplex (MTBC). We aimed to generate a WHO endorsed catalogue of mutations to serve as a global standard for interpreting molecular information for drug resistance prediction. Methods: A candidate gene approach was used to identify mutations as associated with resistance, or consistent with susceptibility, for 13 WHO endorsed anti-tuberculosis drugs. 38,215 MTBC isolates with paired whole-genome sequencing and phenotypic drug susceptibility testing data were amassed from 45 countries. For each mutation, a contingency table of binary phenotypes and presence or absence of the mutation computed positive predictive value, and Fisher's exact tests generated odds ratios and Benjamini-Hochberg corrected p-values. Mutations were graded as Associated with Resistance if present in at least 5 isolates, if the odds ratio was >1 with a statistically significant corrected p-value, and if the lower bound of the 95% confidence interval on the positive predictive value for phenotypic resistance was >25%. A series of expert rules were applied for final confidence grading of each mutation. Findings: 15,667 associations were computed for 13,211 unique mutations linked to one or more drugs. 1,149/15,667 (7·3%) mutations were classified as associated with phenotypic resistance and 107/15,667 (0·7%) were deemed consistent with susceptibility. For rifampicin, isoniazid, ethambutol, fluoroquinolones, and streptomycin, the mutations' pooled sensitivity was >80%. Specificity was over 95% for all drugs except ethionamide (91·4%), moxifloxacin (91·6%) and ethambutol (93·3%). Only two resistance mutations were classified for bedaquiline, delamanid, clofazimine, and linezolid as prevalence of phenotypic resistance was low for these drugs. Interpretation: This first WHO endorsed catalogue of molecular targets for MTBC drug susceptibility testing provides a global standard for resistance interpretation. Its existence should encourage the implementation of molecular diagnostics by National Tuberculosis Programmes. Funding: UNITAID, Wellcome, MRC, BMGF., Unitaid, Wellcome Trust, UK Medical Research Council, and Bill and Melinda Gates Foundation

Background Sex estimation is a critical issue in forensic medicine. Since anthropologic evaluations on radiographs can contribute to more accurate sex estimation, this study measured the length and height, as well as area, of the maxillary sinus on lateral cephalometric radiography. Methods and materials In this descriptive-analytic study, 80 images obtained from 20 to 40-year-old individuals (40 males and 40 female) were selected. The height and anterior-posterior length of the maxillary sinus was performed using CATIA V5R20 (a software package for image analysis). Maxillary sinus area was determined using discriminant analysis in AutoCAD. Findings The mean maxillary sinus height was 40.48 mm in males and 38.7 mm in females. The mean maxillary sinus length was 40.31 mm in males and 37.31 mm in females. The area of the maxillary sinus was 1201.2 mm2 in males and 1043.4 mm2 in females. Two discriminant analysis models, one based on the height and length of the maxillary sinus and the other based on sinus area) were developed for sex estimation. The area under the receiver operating characteristic (ROC) curve was used for quality assessment of the fitted models and determination of their prediction ability. Conclusion The mean height, length and area of the maxillary sinus were significantly larger in males than in females (P

Farnesyltransferase (FTase) is considered as an effective target in treating a variety of cancers. In this investigation, a 3D-QSAR pharmacophore search was performed to identify potential inhibitors against FTase. Correspondingly, 3D-QSAR pharmacophore models for FTase inhibitors were generated utilizing the training set compounds and validated through the test set, cost analysis and Fischer's randomization test. The created pharmacophore models were evaluated based on Debnath's analysis. Then, the pharmacophore model Hypo1 was selected to perform pharmacophore-based screening. Subsequently, the identified compounds were filtered considering Lipinski's Rule of Five (RoF) and Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) properties. In the next step, the inter-molecular interactions of the retrieved compounds and the most active compound of the training set with FTase were analyzed utilizing the flexible docking technique. Eventually, the best two compounds, ZINC08952683 and ZINC08918035, along with the reference compound, ZINC13559176, were selected for Molecular Dynamics (MD) studies in order to conduct an in-depth study on their complexes with FTase. MD results confirmed docking studies and showed that these two compounds could make stable complexes with the FTase active site and may have great inhibitory effects on FTase.

The purpose of this study is to extend a feature set with non-linear features to improve classification rate of guilty and innocent subjects. Non-linear features can provide extra information about phase space. The Event-Related Potential (ERP) signals were recorded from 49 subjects who participated in concealed face recognition test. For feature extraction, at first, several morphological characteristics, frequency bands, and wavelet coefficients (we call them basic-features) are extracted from each single-trial ERP. Recurrence Quantification Analysis (RQA) measures are then computed as non-linear features from each single-trial. We apply Genetic Algorithm (GA) to select the best feature set and this feature set is used for classification of data using Linear Discriminant Analysis (LDA) classifier. Next, we use a new approach to improve classification results based on introducing an adaptive-threshold. Results indicate that our method is able to correctly detect 91.83% of subjects (45 correct detection of 49 subjects) using combination of basic and non-linear features, that is higher than 87.75% for basic and 79.59% for non-linear features. This shows that combination of non-linear and basic- features could improve classification rate.

A mutual interaction between citizens and government has become an important requirement for every successful urban decision making process. As cities develop, such interactions play a greater role in citizen satisfaction. Through these interactions, governments can recognize the needs of citizens and try to address their challenges. In these interactions, the role of the people is central; in fact, it is the people who express their needs to the service-providing organizations through different communication channels. A common channel that has been established in Iran is the ‘137 center,’ a municipal, phone-based request/response system. In this article, information from Municipal District 1 in the city of Bojnourd was gathered, analyzed to prioritize urban needs and assessed for citizen satisfaction. Forty-three citizen needs were identified and categorized based on K-means clustering, the Fuzzy Clustering Method (FCM) and the Imperialist Competitive Algorithm (ICA). The three algorithms were also evaluated. RFM (recency, frequency, monetary) analysis was performed for classification. The clustering methods were then assessed and compared using three parameters: execution time, accuracy and simplicity. The results of the FCM and ICA clustering were similar, however, the execution time for FCM was less than for ICA. Considering the similarity of the results and the flexibility of FCM, it was concluded that, if the execution time was of primary importance, then the use of FCM was more appropriate. In contrast, if accuracy was a priority, ICA was preferred. Our results also showed that if simplicity and speed were required, the K-means algorithm was the best choice. Finally, subjects such as the quality of the asphalt, garbage collection and park development were of primary importance to Bojnourd citizens, therefore the municipality should pay special attention to these subjects.

One of the important steps in the earthquake disaster management is the establishment of temporary relief centers, to provide the basic helps and support in short time. Finding optimum location for these centers with adequate covering of the urban areas is not a trivial problem. The meta-heuristic algorithms are promising methods, capable of solving such complex optimization problems. The goal of this research was to compare the performance of Genetic Algorithm (GA) and Bees Algorithm (BA) in finding the optimum location of relief centers and in allocating of the parcels to them. In order to limit the search space, GIS was used for selecting a few candidate sites that satisfy the initial conditions and criteria. Then, the two algorithms were used to select nine optimum sites among the candidates and to allocate the parcels to them, while minimizing the sum of all distances between centers and parcels. To calibrate the parameters of the algorithms, a simple simulated data set was used. Having proper values for those parameters, the algorithms were tested on the real data of the study area. The results showed that the convergence of the BA was rather gradual, while the trend for GA was relatively stepwise. Both algorithms showed high levels of repeatability. For both the simulated and real data, GA showed to be faster than BA. Simplicity and repeatability of the algorithm are the main factors from the user’s point of view. Therefore, considering these criteria, the GA is more favorable than the BA.

In technical systems like oil and gas drilling systems, an accident sequence starts with an Initiating Event (IE) and evolves over time through the interaction of barriers in terms of success or failure. As it has been dramatically demonstrated in a variety of cases, offshore oil rigs activities have severe consequences to people, asset, environment and reputation. A survey carried out on a leakage event in production phase. The barriers of the above IE are assessed by Event Tree Analysis (ETA) which evaluates the sequence of events in a potential accident scenario following the occurrence of an IE. In this research to calculate Failure Probability (FP) of barriers new approach is proposed. In this methodology, Reliability Block Diagram (RBD) and Fault Tree Analysis (FTA) are employed to quantify barriers FP. RBD is useful tool to quantify FP of barriers with logic diagram. FP of barriers with logic diagram is obtained by FTA. However it is often difficult to estimate precisely the FP of the components due to insufficient data. It has been reported that availability of the FP data pertaining to local conditions is surprisingly limited. In this study to overcome this problem using of expert judgment and then fuzzy logic is employed. Therefore, Fuzzy FTA (FFTA) is used to reduce uncertainty of expert judgment.

BACKGROUND: Nurses serve as the primary source of care for minor patients in intensive care units. Even though they support both patients and their relatives, these nurses may experience moral distress from their profession. While managing their daily relationships with their patients, nurses must also be able to control their actions to feel that they are from a social unit and feel their competence in association with others. OBJECTIVE: This study aimed to investigate the relationship between professional autonomy and moral distress among nurses working in children's units and pediatric intensive care wards. METHODS: This descriptive/comparative cross-sectional study was conducted in 2015 using 120 nurses as subjects. Subjects were selected using the census method. The research tools used to gain measurable data were the Pankratznursing questionnaire(PNQ) and Corley'sMoral distress scale (MDS). In order to analyze the collected data, descriptive statistic tests such as the relative frequency distribution, mean, standard deviation and the Pearson correlation test, T-test, ANOVA, and regression were used. The SPSSv.20 software was also used to analyze the data obtained. RESULTS: The relationship between professional autonomy and moral distress revealed that there was a significant positive relationship between professional autonomy and moral distress in the intensity (r = 0.39; P