Hybrid ACO and TOFA feature selection approach for text classification

With the highly increasing availability of text data on the Internet, the process of selecting an appropriate set of features for text classification becomes more important, for not only reducing the dimensionality of the feature space, but also for improving the classification performance. This paper proposes a novel feature selection approach to improve the performance of text classifier based on an integration of Ant Colony Optimization algorithm (ACO) and Trace Oriented Feature Analysis (TOFA). ACO is metaheuristic search algorithm derived by the study of foraging behavior of real ants, specifically the pheromone communication to find the shortest path to the food source. TOFA is a unified optimization framework developed to integrate and unify several state-of-the-art dimension reduction algorithms through optimization framework. It has been shown in previous research that ACO is one of the promising approaches for optimization and feature selection problems. TOFA is capable of dealing with large scale text data and can be applied to several text analysis applications such as text classification, clustering and retrieval. For classification performance yet effective, the proposed approach makes use of TOFA and classifier performance as heuristic information of ACO. The results on Reuters and Brown public datasets demonstrate the effectiveness of the proposed approach. © 2012 IEEE

Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy

Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe

Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

Azithromycin and dexamethasone loaded β-glucan films for the treatment of blepharitis

Background: Blepharitis is considered one of the most common ocular surface conditions in optometry and ophthalmology practice. While azithromycin and dexamethasone have been used successfully to treat blepharitis, they are generally formulated as eye drops requiring frequent administration. Ocular inserts based on biodegradable polymers may overcome some of the problems associated with conventional eye drops such as the fast nasolacrimal drainage. Methods: Inserts with different β-glucan and hydroxypropyl methycellulose (HPMC) compositions were prepared using the solvent-casting method and evaluated in terms of their appearance, thickness, weight, pH, mechanical strength, bioadhesive properties and drug-polymer interactions. The ability of the ocular inserts to provide controlled release of the drugs was assessed through an in vitro release study of dexamethasone and an antibacterial assay for azithromycin. Results: All parameters were found acceptable for ocular use, with the film laminate exhibiting the highest tensile strength and mucoadhesion. Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR) revealed that the drugs were molecularly dispersed within the polymer films with no obvious interactions. Dexamethasone release was fast with 100% released within 1 hr. Azithromycin also showed a high burst release achieving the minimum inhibitory concentration after only 5 min; however, antibacterial activity was maintained for 24 hrs. Conclusion: Ocular inserts were successfully prepared and delivered both drugs over prolonged periods compared to conventional eye drops. However, additional coating may be required to further control the drug release

Antibacterial activity of trimetal (CuZnFe) oxide nanoparticles

Khalid E Alzahrani,1,2 Abdurahman A Niazy,3 Abdullah M Alswieleh,4 Rizwan Wahab,5 Ahmed M El-Toni,2 Hamdan S Alghamdi3 1Department of Physics and Astronomy, King Saud University, Riyadh, Kingdom of Saudi Arabia; 2King Abdullah Institute for Nanotechnology, King Saud University, Riyadh, Kingdom of Saudi Arabia; 3Prince Naif Health Research Center, Molecular and Cell Biology Laboratory, College of Dentistry, King Saud University, Riyadh, Kingdom of Saudi Arabia; 4Department of Chemistry, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia; 5Department of Zoology,&nbsp;College of Science, King Saud University, Riyadh, Kingdom of&nbsp;Saudi Arabia Background: The increasing resistance of pathogenic bacteria to antibiotics is a challenging worldwide health problem that has led to the search for new and more efficient antibacterial agents. Nanotechnology has proven to be an effective tool for the fight against bacteria. Methods: In this paper, we present the synthesis and traits of trimetal (CuZnFe) oxide nanoparticles (NPs) using X-ray diffraction, high-resolution transmission electron microscopy, and energy dispersive x-ray spectroscopy. We evaluated the antibacterial activity of these NPs against gram-negative Escherichia coli and gram-positive Enterococcus faecalis and then compared it to that of their pure single-metal oxide components CuO and ZnO. Results: Our study showed that the antibacterial activity of the trimetal oxide NPs was greater against E. coli than against E. faecalis. Overall, the antimicrobial effect of trimetal NPs is between those of pure ZnO and CuO nanoparticles, which may mean that their cytotoxicity is also between that of pure ZnO and CuO NPs, making them potential antibiotics. However, the cytotoxicity of trimetal NPs to mammalian cells needs to be verified. Conclusion: The combination of three metal oxide NPs (ZnO, CuO, and Fe2O3) in one multimetal (CuZnFe) oxide NPs will enhance the therapeutic strategy against a wide range of microbial infections. Bacteria are unlikely to develop resistance against this new NP because bacteria must go through a series of mutations to become resistant to the trimetal oxide NP. Therefore, this NP can combat existing and emerging bacterial infections. Keywords: nanotechnology, antibacterial agents, nanoparticles, trimetal nanoparticles, Escherichia coli, Enterococcus faecali