Fabrication and Evaluation of 2-Hydroxyethyl Methacrylate-co-Acrylic Acid Hydrogels for Sustained Nicorandil Delivery

Purpose: To fabricate and evaluate oral 2-hydroxyethyl methacrylate co-acrylic acid hydrogels as a drug delivery system for sustained release of nicorandil.Methods: HEMA-co-AA hydrogels using different monomer concentrations were prepared by free radical polymerization. N, N-methylene bis acrylamide (MBA) was used as crosslinker and potassium persulphate (KPS) as initiator. Nicorandil (20 mg) loaded hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis and differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) . Swelling ratio, equilibrium swelling (ES), gel content (gc), porosity measurement (P) and in vitro drug release of the delivery system were evaluated.Results: Swelling ratio and ES decreased as AA concentration (%) was reduced from 3.173 to 2.93 (pH 1.2) and 16.42 to 15.01 (pH 7.4) and 68.49 to 65.90 (pH 1.2) and 93.91 to 93.34 (pH 7.4), respectively, while HEMA and MBA showed opposite effects. Gel content (%) and porosity (%) ranged from 83.76 to 88.0, respectively from F1 to F9. With increase monomer content (AA), drug release increased from 85.99 to 89.38 %. However, when the concentrations of HEMA and MBA were raised, drug release decreased.Conclusion: HEMA-co-AA hydrogels are potential pH-sensitive and sustained-release system for nicorandil.Keywords: Hydrogel, 2-Hydroxyethyl Methacrylate-co-acrylic Acid, Sustained Drug Release, Monomer, Nicorandil, Swelling Ratio, Porosit

Identification of leaf rust resistant gene Lr10 in Pakistani wheat germplasm

Leaf (brown) rust is the major disease of wheat in Pakistan and other countries. The disease is more effectively controlled when several rust resistance genes are pyramided into a single line. Molecular survey was conducted to screen 25 Pakistan wheat germplasm for the presence of leaf rust resistance gene Lr10 using specific STS primer. The survey revealed that out of the 25 germplasm/lines grown in Hazara University Botanic garden, 18 genotypes were observed with Lr10 gene, while seven genotypes did not show the presence of Lr10 gene. The identification of Lr10 in Pakistan wheat germplasm will help in accelerating the breeding program in future, including the pyramiding of different resistant genes in wheat varieties.Key words: Wheat, leaf rust, Lr10, molecular markers

Population‐based cohort study of outcomes following cholecystectomy for benign gallbladder diseases

Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all‐cause 30‐day readmissions and complications in a prospective population‐based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all‐cause 30‐day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two‐level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics

Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112

A novel psychrophilic alkaline phosphatase from the metagenome of tidal flat sediments

BACKGROUND: Alkaline phosphatase (AP) catalyzes the hydrolytic cleavage of phosphate monoesters under alkaline conditions and plays important roles in microbial ecology and molecular biology applications. Here, we report on the first isolation and biochemical characterization of a thermolabile AP from a metagenome. RESULTS: The gene encoding a novel AP was isolated from a metagenomic library constructed with ocean-tidal flat sediments from the west coast of Korea. The metagenome-derived AP (mAP) gene composed of 1,824 nucleotides encodes a polypeptide with a calculated molecular mass of 64 kDa. The deduced amino acid sequence of mAP showed a high degree of similarity to other members of the AP family. Phylogenetic analysis revealed that the mAP is shown to be a member of a recently identified family of PhoX that is distinct from the well-studied classical PhoA family. When the open reading frame encoding mAP was cloned and expressed in recombinant Escherichia coli, the mature mAP was secreted to the periplasm and lacks an 81-amino-acid N-terminal Tat signal peptide. Mature mAP was purified to homogeneity as a monomeric enzyme with a molecular mass of 56 kDa. The purified mAP displayed typical features of a psychrophilic enzyme: high catalytic activity at low temperature and a remarkable thermal instability. The optimal temperature for the enzymatic activity of mAP was 37°C and complete thermal inactivation of the enzyme was observed at 65°C within 15 min. mAP was activated by Ca(2+) and exhibited maximal activity at pH 9.0. Except for phytic acid and glucose 1-phosphate, mAP showed phosphatase activity against various phosphorylated substrates indicating that it had low substrate specificity. In addition, the mAP was able to remove terminal phosphates from cohesive and blunt ends of linearized plasmid DNA, exhibiting comparable efficiency to commercially available APs that have been used in molecular biology. CONCLUSIONS: The presented mAP enzyme is the first thermolabile AP found in cold-adapted marine metagenomes and may be useful for efficient dephosphorylation of linearized DNA

Transport in Anisotropic Superfluids: A Holographic Description

We study transport phenomena in p-wave superfluids in the context of gauge/gravity duality. Due to the spacetime anisotropy of this system, the tensorial structure of the transport coefficients is non-trivial in contrast to the isotropic case. In particular, there is an additional shear mode which leads to a non-universal value of the shear viscosity even in an Einstein gravity setup. In this paper, we present a complete study of the helicity two and helicity one fluctuation modes. In addition to the non-universal shear viscosity, we also investigate the thermoelectric effect, i.e. the mixing of electric and heat current. Moreover, we also find an additional effect due to the anisotropy, the so-called flexoelectric effect.Comment: 38 pages, 11 figures; v2: typos corrected. arXiv admin note: substantial text overlap with arXiv:1011.591

Experimental characterisation on the behaviour of PLLA for stretch blowing moulding of bioresorbable vascular scaffolds

Processing tubes from poly (l-lactic acid) (PLLA) by stretch blow moulding (SBM) is used in the manufacture of bioresorbable vascular scaffolds (BVS) to improve their mechanical performance. To better understand this processing technique, a novel experimental setup by free stretch blow inside a water bath was developed to visualise the tube forming process and analyse the deformation behaviour. PLLA tubes were heated, stretched and blown with no mould present inside a temperature-controlled water bath whilst recording the processing parameters (axial force, inflation pressure). The onset of pressure activation relative to the axial stretch was controlled deliberately to produce a simultaneous (SIM) or sequential (SEQ) mode of deformation. Real-time images of the tube during forming were captured using high speed cameras and the surface strain of the patterned tube was extracted using digital image correlation (DIC). The deformation characteristics of PLLA tubes in SBM was quantified by analysis of shape evolution, strain history and stress-strain relationship