Browse publications by year: 2017

  1. Boyero L, Graça MAS, Tonin AM, Pérez J, J Swafford A, Ferreira V, et al.
    Sci Rep, 2017 09 05;7(1):10562.
    PMID: 28874830 DOI: 10.1038/s41598-017-10640-3
    Plant litter represents a major basal resource in streams, where its decomposition is partly regulated by litter traits. Litter-trait variation may determine the latitudinal gradient in decomposition in streams, which is mainly microbial in the tropics and detritivore-mediated at high latitudes. However, this hypothesis remains untested, as we lack information on large-scale trait variation for riparian litter. Variation cannot easily be inferred from existing leaf-trait databases, since nutrient resorption can cause traits of litter and green leaves to diverge. Here we present the first global-scale assessment of riparian litter quality by determining latitudinal variation (spanning 107°) in litter traits (nutrient concentrations; physical and chemical defences) of 151 species from 24 regions and their relationships with environmental factors and phylogeny. We hypothesized that litter quality would increase with latitude (despite variation within regions) and traits would be correlated to produce 'syndromes' resulting from phylogeny and environmental variation. We found lower litter quality and higher nitrogen:phosphorus ratios in the tropics. Traits were linked but showed no phylogenetic signal, suggesting that syndromes were environmentally determined. Poorer litter quality and greater phosphorus limitation towards the equator may restrict detritivore-mediated decomposition, contributing to the predominance of microbial decomposers in tropical streams.
    MeSH terms: Nitrogen/metabolism; Phosphorus/metabolism; Plants/metabolism*; Tropical Climate*; Ecosystem*; Plant Leaves/metabolism*; Rivers*
  2. Khan I, Kumar H, Mishra G, Gothwal A, Kesharwani P, Gupta U
    Curr Pharm Des, 2017;23(35):5315-5326.
    PMID: 28875848 DOI: 10.2174/1381612823666170829164828
    BACKGROUND: Delivery of chemotherapeutic drugs for the diagnosis and treatment of cancer is becoming advanced day by day. However, the challenge of the effective delivery system still does exist. In various types of cancers, breast cancer is the most commonly diagnosed cancer among women. Breast cancer is a combination of different diseases. It cannot be considered as only one entity because there are many specific patient factors, which are involved in the development of this disease. Nanotechnology has opened a new area in the effective treatment of breast cancer due to the several benefits offered by this technology.

    METHODS: Polymeric nanocarriers are among one of the effective delivery systems, which has given promising results in the treatment of breast cancers. Nanocarriers does exert their anticancer effect either through active or passive targeting mode.

    RESULTS: The use of nanocarriers has been resolute about the adverse effects of chemotherapeutic drugs such as poor solubility and less penetrability in tumor cells.

    CONCLUSION: The present review is focused on recent developments regarding polymeric nanocarriers, such as polymeric micelles, polymeric nanoparticles, dendrimers, liposomes, nanoshells, fullerenes, carbon nanotubes (CNT) and quantum dots, etc. for their recent advancements in breast cancer therapy.

    MeSH terms: Animals; Antineoplastic Agents/administration & dosage*; Antineoplastic Agents/metabolism; Breast Neoplasms/drug therapy*; Breast Neoplasms/metabolism; Drug Carriers/administration & dosage*; Drug Carriers/metabolism; Female; Humans; Polymers/administration & dosage*; Polymers/metabolism; Treatment Outcome; Disease Management*; Nanoparticles/administration & dosage*; Nanoparticles/metabolism
  3. Pourshahrestani S, Zeimaran E, Kadri NA, Gargiulo N, Jindal HM, Naveen SV, et al.
    ACS Appl Mater Interfaces, 2017 Sep 20;9(37):31381-31392.
    PMID: 28836753 DOI: 10.1021/acsami.7b07769
    Chitosan-based hemostats are promising candidates for immediate hemorrhage control. However, they have some disadvantages and require further improvement to achieve the desired hemostatic efficiency. Here, a series of 1% Ga2O3-containing mesoporous bioactive glass-chitosan composite scaffolds (Ga-MBG/CHT) were constructed by the lyophilization process and the effect of various concentrations of Ga-MBG (10, 30, and 50 wt %) on the hemostatic function of the CHT scaffold was assessed as compared to that of Celox Rapid gauze (CXR), a current commercially available chitosan-coated hemostatic gauze. The prepared scaffolds exhibited >79% porosity and showed increased water uptake compared to that in CXR. The results of coagulation studies showed that pure CHT and composite scaffolds exhibited increased hemostatic performance with respect to CXR. Furthermore, the composite scaffold with the highest Ga-MBG content (50 wt %) had increased capability to enhancing thrombus generation, blood clotting, and platelet adhesion and aggregation than that of the scaffold made of pure CHT. The antibacterial efficacy and biocompatibility of the prepared scaffolds were also assessed by a time-killing assay and an Alamar Blue assay, respectively. Our results show that the antibacterial effect of 50% Ga-MBG/CHT was more pronounced than that of CHT and CXR. The cell viability results also demonstrated that Ga-MBG/CHT composite scaffolds had good biocompatibility, which facilitates the spreading and proliferation of human dermal fibroblast cells even with 50 wt % Ga-MBG loading. These results suggest that Ga-MBG/CHT scaffolds could be a promising hemostatic candidate for improving hemostasis in critical situations.
    MeSH terms: Gallium/chemistry*; Glass; Hemostatics; Humans; Porosity; Chitosan; Cell Proliferation; Tissue Scaffolds
  4. James PB, Rehman IU, Bah AJ, Lahai M, Cole CP, Khan TM
    BMC Public Health, 2017 09 05;17(1):692.
    PMID: 28870202 DOI: 10.1186/s12889-017-4700-2
    BACKGROUND: Vaccinating healthcare professionals against influenza is considered an effective infection control measure. However, there is a low uptake of influenza vaccine among healthcare professionals around the globe. Currently, it is unknown whether healthcare professionals in Sierra Leone are aware of, and have been vaccinated against influenza. Also, there is a paucity of research evidence on their level of knowledge and attitude toward influenza vaccination. This study assessed healthcare professionals' current influenza vaccine uptake rate, reasons for not getting vaccinated as well as their awareness, knowledge of, and attitude towards influenza vaccination in Freetown Sierra Leone.

    METHOD: A cross-sectional study was conducted between February and April 2016 among healthcare providers working in four public and two private health facilities in Freetown Sierra Leone. Linear regression analysis, one-way ANOVA and independent t-test were employed for data analysis.

    RESULTS: Among 706 respondents that participated in the study more than half were females 378 (53.6%), nurses 425 (60.4%), and the majority were between the age group of 20-39 years 600 (85.3%). Only 46 (6.5%) were vaccinated against influenza. Key reasons for not vaccinated against influenza were less awareness about influenza vaccination among HCPs 580 (82.73%) with (β = 0.154; CI 0.058-0.163), the high cost of influenza vaccines and therefore not normally purchased 392 (55.92%) having (β = 0.150; CI 0.063-0.186). More than half believed that HCPs are less susceptible to influenza infections than other people. Also, majority 585 (84.3%) of HCPs thought that influenza disease could be transmitted after symptoms appear. In addition, 579 (83.2%) of HCPs felt that symptoms usually appear 8-10 days after exposure. Close to half 321 (46.0%) of HCPs were not aware of the influenza immunisation guidelines published by the Advisory Committee on Immunization Practices and Centre for Disease Control.

    CONCLUSION: Influenza vaccine coverage among healthcare professionals in Freetown Sierra Leone was low. High cost, inadequate knowledge about influenza and its vaccine as well as the lack of awareness of vaccine availability were key barriers. Increasing access to influenza vaccine and the use of appropriate educational interventions to increase knowledge and awareness are required to improve influenza vaccination coverage among HCPs.

    MeSH terms: Adult; Cross-Sectional Studies; Female; Health Personnel/psychology*; Health Personnel/statistics & numerical data; Humans; Influenza, Human/prevention & control*; Influenza Vaccines/administration & dosage*; Health Knowledge, Attitudes, Practice*; Male; Middle Aged; Sierra Leone; Vaccination/utilization*; Young Adult
  5. Hussain RM, Razak ZNRA, Saad WMM, Mustakim M
    Asian Pac J Trop Med, 2017 Jul;10(7):685-695.
    PMID: 28870345 DOI: 10.1016/j.apjtm.2017.07.009
    OBJECTIVE: To investigate the effects of Andrographis paniculata (Burm.f.) Wall. Ex Nees (A. paniculata) on expressions and activities of catalase, superoxide dismutase and alkylhydroperoxide reductase C in Staphylococcus aureus (S. aureus) with respect to its survival in vitro.

    METHODS: Antioxidative property of methanolic leaves extract of A. paniculata (0.06 mg/mL). Minimum inhibitory concentration (MIC) was determined by its ability to reduce hydrogen peroxide (H2O2) toxicity against S. aureus ATCC 25923 [(3.8 × 108) cfu/mL]. Effects of the extract on expressions of katA (encoding catalase), sodA and sodM [encoding superoxide dismutases (SODs)], and ahpC [encoding alkylhydroperoxide reductase C (AhpC)] in S. aureus were determined by RT-qPCR and corresponding enzyme activity assays were performed. Nitroblue tetrazolium reduction (NBT) assay was performed to determine effects of the extract on intracellular and extracellular levels of O2- in S. aureus.

    RESULTS: Cells challenged with 7.5 mmol/L H2O2 showed 0% survival in 30 min whereas 25% survived after treatment with the extract and H2O2. Cells that were treated with the extract alone had 43% survival in the same exposure period. Expressions of sodA and sodM genes in extract-treated cells were lowered 0.8-fold and 0.7-fold, respectively with decrease in total SOD activity of 26.8 U compared to untreated cells, 32.4 U (P 

  6. Rahman NIA, Abdul Murad NA, Mollah MM, Jamal R, Harun R
    Front Pharmacol, 2017;8:540.
    PMID: 28871224 DOI: 10.3389/fphar.2017.00540
    About 40% of lung cancer cases globally are diagnosed at the advanced stage. Lung cancer has a high mortality and overall survival in stage I disease is only 70%. This study was aimed at finding a candidate of transcription regulator that initiates the mechanism for metastasis by integrating computational and functional studies. The genes involved in lung cancer were retrieved using in silico software. 10 kb promoter sequences upstream were scanned for the master regulator. Transient transfection of shRNA NFIXs were conducted against A549 and NCI-H1299 cell lines. qRT-PCR and functional assays for cell proliferation, migration and invasion were carried out to validate the involvement of NFIX in metastasis. Genome-wide gene expression microarray using a HumanHT-12v4.0 Expression BeadChip Kit was performed to identify differentially expressed genes and construct a new regulatory network. The in silico analysis identified NFIX as a master regulator and is strongly associated with 17 genes involved in the migration and invasion pathways including IL6ST, TIMP1 and ITGB1. Silencing of NFIX showed reduced expression of IL6ST, TIMP1 and ITGB1 as well as the cellular proliferation, migration and invasion processes. The data was integrated with the in silico analyses to find the differentially expressed genes. Microarray analysis showed that 18 genes were expressed differentially in both cell lines after statistical analyses integration between t-test, LIMMA and ANOVA with Benjamini-Hochberg adjustment at p-value < 0.05. A transcriptional regulatory network was created using all 18 genes, the existing regulated genes including the new genes PTCH1, NFAT5 and GGCX that were found highly associated with NFIX, the master regulator of metastasis. This study suggests that NFIX is a promising target for therapeutic intervention that is expected to inhibit metastatic recurrence and improve survival rate.
    MeSH terms: Analysis of Variance; Cell Line; Genes, Regulator; Lung Neoplasms; Software; Transfection; Survival Rate; Polymerase Chain Reaction; Tissue Inhibitor of Metalloproteinase-1; RNA, Small Interfering; Microarray Analysis; Cell Proliferation
  7. Sharma D, Patel RP, Zaidi STR, Sarker MMR, Lean QY, Ming LC
    Front Pharmacol, 2017;8:546.
    PMID: 28871228 DOI: 10.3389/fphar.2017.00546
    Ciprofloxacin, a second generation broad spectrum fluoroquinolone, is active against both Gram-positive and Gram-negative bacteria. Ciprofloxacin has a high oral bioavailability and a large volume of distribution. It is used for the treatment of a wide range of infections including urinary tract infections caused by susceptible bacteria. However, the availability and use of substandard and spurious quality of oral ciprofloxacin formulations in the developing countries has been thought to have contributed toward increased risk of treatment failure and bacterial resistance. Therefore, quality control and bioequivalence studies of the commercially available oral ciprofloxacin formulations should be monitored. Appropriate actions should be taken against offending manufacturers in order to prevent the sale of substandard and spurious quality of ciprofloxacin formulations.
    MeSH terms: Bacterial Infections; Biological Availability; Ciprofloxacin; Developing Countries; Gram-Negative Bacteria; Quality Control; Therapeutic Equivalency; Urinary Tract Infections; Treatment Failure; Fluoroquinolones
  8. Farawahida AH, Jinap S, Nor-Khaizura MAR, Samsudin NIP
    PMID: 28871861 DOI: 10.1080/19440049.2017.1375605
    Among the many roles played by small and medium enterprises (SMEs) in the food industry is the production of heritage foods such as peanut sauce. Unfortunately, the safety of peanut sauce is not always assured as the processing line is not controlled. Peanut sauce is usually made of peanuts and chilli, and these commodities are normally contaminated with Aspergillus spp. and aflatoxins (AFs). Hence, the objective of this study was to evaluate the practices related to reduction of AF hazard and the effect of interventions in peanut sauce processing. Peanut samples were collected from each step of peanut sauce processing from a small peanut sauce company according to four designs: (1) control; (2) oil-less frying of chilli powder; (3) addition of retort processing; and (4) combination of oil-less frying of chilli powder and retort processing. Oil-less frying of chilli powder (Design 2) reduced total AFs by 33-41%, retort processing (Design 3) reduced total AFs by 49%, while combination of these two thermal processes (Design 4) significantly reduced total AFs, by 57%. The present work demonstrated that Design 4 yielded the highest reduction of total AFs and is therefore recommended to be employed by SME companies.
    MeSH terms: Aflatoxins/analysis*; Aspergillus/chemistry*; Food Contamination/analysis*; Arachis/chemistry*; Plant Oils/analysis*; Powders/analysis; Spices/analysis*
  9. Fonseka HA, Ameruddin AS, Caroff P, Tedeschi D, De Luca M, Mura F, et al.
    Nanoscale, 2017 Sep 21;9(36):13554-13562.
    PMID: 28872181 DOI: 10.1039/c7nr04598k
    The usability and tunability of the essential InP-InGaAs material combination in nanowire-based quantum wells (QWs) are assessed. The wurtzite phase core-multi-shell InP-InGaAs-InP nanowire QWs are characterised using cross-section transmission electron microscopy and photoluminescence measurements. The InP-InGaAs direct interface is found to be sharp while the InGaAs-InP inverted interface is more diffused, in agreement with their planar counterpart. Bright emission is observed from the single nanowires containing the QWs at room temperature, with no emission from the InP core or outer barrier. The tunability of the QW emission wavelength in the 1.3-1.55 μm communication wavelength range is demonstrated by varying the QW thickness and in the 1.3 μm range by varying the composition. The experiments are supported by simulation of the emission wavelength of the wurtzite phase InP-InGaAs QWs in the thickness range considered. The radial heterostructure is further extended to design multiple QWs with bright emission, therefore establishing the capability of this material system for nanowire based optical devices for communication applications.
  10. Chaubal TV, Bapat RA, Shetty D
    Contact Derm., 2017 Oct;77(4):251-252.
    PMID: 28872204 DOI: 10.1111/cod.12794
    MeSH terms: Adult; Camphor/adverse effects; Camphor/analogs & derivatives*; Humans; Male; Patch Tests; Periodontal Dressings/adverse effects*; Resins, Synthetic/adverse effects*; Stomatitis/diagnosis*; Stomatitis/etiology; Dermatitis, Allergic Contact/diagnosis*; Dermatitis, Allergic Contact/etiology
  11. Md Nasir NL, Kamsani NE, Mohtarrudin N, Othman F, Md Tohid SF, Zakaria ZA
    Pharm Biol, 2017 Dec;55(1):2102-2109.
    PMID: 28872373 DOI: 10.1080/13880209.2017.1371769
    CONTEXT: Leaves of Muntingia calabura (Elaeocarpaceae) are widely used in traditional medical practice; scientific findings show various pharmacological activities. However, its anticancer effect has not been investigated thoroughly yet.

    OBJECTIVE: The objective of this study is to study the chemoprevention effects of MEMCL against azoxymethane (AOM)-induced colon cancer and to examine the involvement of endogenous antioxidants Materials and methods: Male Sprague-Dawley rats, divided into five groups (n = 7), were injected intraperitoneally once weekly for 2 weeks with 15 mg/kg AOM, except for the normal group (received saline). The animals were then administered orally for 8 weeks with 8% Tween-80 (vehicle; normal group), 8% Tween-80 (vehicle; cancer group) or, 50, 250 or 500 mg/kg MEMC. After treatments, colon samples were collected from each rat for the histopathological analysis, quantification of aberrant crypt foci formed and determination of colon antioxidant levels. MEMC was also subjected to HPLC analysis.

    RESULTS: The extract exerted significant (p 

    MeSH terms: Methanol/pharmacology; Methanol/therapeutic use; Animals; Antineoplastic Agents, Phytogenic/isolation & purification; Antineoplastic Agents, Phytogenic/pharmacology; Antineoplastic Agents, Phytogenic/therapeutic use*; Antioxidants/metabolism*; Azoxymethane/toxicity; Colon/drug effects; Colon/metabolism; Colonic Neoplasms/chemically induced; Colonic Neoplasms/drug therapy*; Colonic Neoplasms/metabolism*; Flavonoids/metabolism*; Male; Plant Extracts/isolation & purification; Plant Extracts/pharmacology; Plant Extracts/therapeutic use; Rats, Sprague-Dawley; Plant Leaves; Elaeocarpaceae*; Rats
  12. Chua SY, Guo N, Tan CS, Wang X
    Sensors (Basel), 2017 Sep 05;17(9).
    PMID: 28872589 DOI: 10.3390/s17092031
    Accuracy is an important measure of system performance and remains a challenge in 3D range gated reconstruction despite the advancement in laser and sensor technology. The weighted average model that is commonly used for range estimation is heavily influenced by the intensity variation due to various factors. Accuracy improvement in term of range estimation is therefore important to fully optimise the system performance. In this paper, a 3D range gated reconstruction model is derived based on the operating principles of range gated imaging and time slicing reconstruction, fundamental of radiant energy, Laser Detection And Ranging (LADAR), and Bidirectional Reflection Distribution Function (BRDF). Accordingly, a new range estimation model is proposed to alleviate the effects induced by distance, target reflection, and range distortion. From the experimental results, the proposed model outperforms the conventional weighted average model to improve the range estimation for better 3D reconstruction. The outcome demonstrated is of interest to various laser ranging applications and can be a reference for future works.
    MeSH terms: Lasers; Technology; Imaging, Three-Dimensional; Physical Phenomena
  13. Kuzmina O, Hassan NH, Patel L, Ashworth C, Bakis E, White AJP, et al.
    Dalton Trans, 2017 Sep 28;46(36):12185-12200.
    PMID: 28872646 DOI: 10.1039/c7dt02372c
    Solvatochromic transition metal (TM)-complexes with weakly associating counter-anions are often used to evaluate traditional neutral solvent and anion coordination ability. However, when employed in ionic liquids (IL) many of the common assumptions made are no longer reliable. This study investigates the coordinating ability of weakly coordinating IL anions in traditional solvents and within IL solvents employing a range of solvatochromic copper complexes. Complexes of the form [Cu(acac)(tmen)][X] (acac = acetylacetonate, tmen = tetramethylethylenediamine) where [X]-= [ClO4]-, Cl-, [NO3]-, [SCN]-, [OTf]-, [NTf2]-and [PF6]-have been synthesised and characterised both experimentally and computationally. ILs based on these anions and imidazolium and pyrrolidinium cations, some of which are functionalised with hydroxyl and nitrile groups, have been examined. IL-anion coordination has been investigated and compared to typical weakly coordinating anions. We have found there is potential for competition at the Cu-centre and cases of anions traditionally assigned as weakly associating that demonstrate a stronger than expected level of coordinating ability within ILs. [Cu(acac)(tmen)][PF6] is shown to contain the least coordinating anion and is established as the most sensitive probe studied here. Using this probe, the donor numbers (DNs) of ILs have been determined. Relative donor ability is further confirmed based on the UV-Vis of a neutral complex, [Cu(sacsac)2] (sacsac = dithioacetylacetone), and DNs evaluated via23Na NMR spectroscopy. We demonstrate that ILs can span a wide donor range, similar in breadth to conventional solvents.
  14. DeCarlo C, Omar AH, Haroun MI, Bigler L, Bin Rais MN, Abu J, et al.
    Vector Borne Zoonotic Dis, 2017 10;17(10):709-713.
    PMID: 28873035 DOI: 10.1089/vbz.2016.2098
    West Nile virus (WNV) is a zoonotic single-strand RNA arbovirus (family Flaviviridae: Flavivirus), transmitted among avian hosts in enzootic cycles by a mosquito vector. The virus has a significant disease effect on humans and equines when it bridges into a cycle with various sequelae with epidemic potential. This study was carried out to identify the potential spectrum of WNV hosts in three geographic areas with climatologically distinct features: Malaysia, Qatar, and the United States of America (U.S.). Serum samples were collected from avian and mammal species suspected to be reservoirs for the virus at these areas in a cross-sectional epidemiologic study. The samples were tested for the presence of antibodies against the virus using an enzyme-linked immunosorbent assay. Data on putative risk factors were also collected and analyzed for significance of association with seropositivity using the logistic regression analysis. Among the tested avian and mammalian species, raccoons had the highest seroconversion rate (54%) followed by crows (30%), horses (27%), camels (10%), other avian species (7%), and canine species (3%). It was almost twice as likely to detect seroconversion among these mammalian and avian species in the fall in comparison to other seasons of the year. Only mammalian and avian species and seasons of the year were significantly associated with the likelihood of seroconversion to WNV when we controlled for other factors in the multivariate analysis. Our data from the U.S. showed that raccoons and camels are susceptible to infection by the virus and may play a role in the perpetuation of endemic foci for the disease.
    MeSH terms: Animals; Birds/virology*; Climate; Disease Reservoirs/veterinary*; Malaysia/epidemiology; Mammals/virology*; Qatar/epidemiology; United States/epidemiology; West Nile Fever/epidemiology; West Nile Fever/veterinary*; West Nile Fever/virology; West Nile virus/isolation & purification*; Zoonoses
  15. Amin AM, Sheau Chin L, Teh CH, Mostafa H, Mohamed Noor DA, Sk Abdul Kader MA, et al.
    J Pharm Biomed Anal, 2017 Nov 30;146:135-146.
    PMID: 28873361 DOI: 10.1016/j.jpba.2017.08.018
    Clopidogrel high on treatment platelets reactivity (HTPR) has burdened achieving optimum therapeutic outcome. Although there are known genetic and non-genetic factors associated with clopidogrel HTPR, which explain in part clopidogrel HTPR, yet, great portion remains unknown, often hindering personalizing antiplatelet therapy. Nuclear magnetic resonance (1H NMR) pharmacometabolomics analysis is useful technique to phenotype drug response. We investigated using 1H NMR analysis to phenotype clopidogrel HTPR in urine. Urine samples were collected from 71 coronary artery disease (CAD) patients who were planned for interventional angiographic procedure prior to taking 600mg clopidogrel loading dose (LD) and 6h post LD. Patients' platelets function testing was assessed with the VerifyNow® P2Y12 assay at 6h after LD. Urine samples were analysed using 1H NMR. Multivariate statistical analysis was used to identify metabolites associated with clopidogrel HTPR. In pre-dose samples, 16 metabolites were associated with clopidogrel HTPR. However, 18 metabolites were associated with clopidogrel HTPR in post-dose samples. The pathway analysis of the identified biomarkers reflected that multifactorial conditions are associated with clopidogrel HTPR. It also revealed the implicated role of gut microbiota in clopidogrel HTPR. Pharmacometabolomics not only discovered novel biomarkers of clopidogrel HTPR but also revealed implicated pathways and conditions.
    MeSH terms: Blood Platelets/drug effects*; Coronary Artery Disease/drug therapy*; Coronary Artery Disease/urine*; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Platelet Aggregation Inhibitors/therapeutic use*; Platelet Aggregation Inhibitors/urine*; Ticlopidine/analogs & derivatives*; Ticlopidine/therapeutic use; Ticlopidine/urine; Biomarkers/urine; Proton Magnetic Resonance Spectroscopy/methods
  16. Adamu A, Wahab RA, Shamsir MS, Aliyu F, Huyop F
    Comput Biol Chem, 2017 Oct;70:125-132.
    PMID: 28873365 DOI: 10.1016/j.compbiolchem.2017.08.007
    The l-2-haloacid dehalogenases (EC 3.8.1.2) specifically cleave carbon-halogen bonds in the L-isomers of halogenated organic acids. These enzymes have potential applications for the bioremediation and synthesis of various industrial products. One such enzyme is DehL, the l-2-haloacid dehalogenase from Rhizobium sp. RC1, which converts the L-isomers of 2-halocarboxylic acids into the corresponding D-hydroxycarboxylic acids. However, its catalytic mechanism has not been delineated, and to enhance its efficiency and utility for environmental and industrial applications, knowledge of its catalytic mechanism, which includes identification of its catalytic residues, is required. Using ab initio fragment molecular orbital calculations, molecular mechanics Poisson-Boltzmann surface area calculations, and classical molecular dynamic simulation of a three-dimensional model of DehL-l-2-chloropropionic acid complex, we predicted the catalytic residues of DehL and propose its catalytic mechanism. We found that when Asp13, Thr17, Met48, Arg51, and His184 were individually replaced with an alanine in silico, a significant decrease in the free energy of binding for the DehL-l-2-chloropropionic acid model complex was seen, indicating the involvement of these residues in catalysis and/or structural integrity of the active site. Furthermore, strong inter-fragment interaction energies calculated for Asp13 and L-2-chloropropionic acid, and for a water molecule and His184, and maintenance of the distances between atoms in the aforementioned pairs during the molecular dynamics run suggest that Asp13 acts as the nucleophile and His184 activates the water involved in DehL catalysis. The results of this study should be important for the rational design of a DehL mutant with improved catalytic efficiency.
    MeSH terms: Amino Acids/metabolism*; Amino Acids/chemistry; Computer Simulation*; Hydrolases/metabolism*; Hydrolases/chemistry; Rhizobium/enzymology*; Computational Biology*; Biocatalysis; Molecular Dynamics Simulation*
  17. Lee KY, Wan Ahmad WA, Low EV, Liau SY, Anchah L, Hamzah S, et al.
    PLoS One, 2017;12(9):e0184410.
    PMID: 28873473 DOI: 10.1371/journal.pone.0184410
    INTRODUCTION: The increasing disease burden of coronary artery disease (CAD) calls for sustainable cardiac service. Teaching hospitals and general hospitals in Malaysia are main providers of percutaneous coronary intervention (PCI), a common treatment for CAD. Few studies have analyzed the contemporary data on local cardiac facilities. Service expansion and budget allocation require cost evidence from various providers. We aim to compare the patient characteristics, procedural outcomes, and cost profile between a teaching hospital (TH) and a general hospital (GH).

    METHODS: This cross-sectional study was conducted from the healthcare providers' perspective from January 1st to June 30th 2014. TH is a university teaching hospital in the capital city, while GH is a state-level general hospital. Both are government-funded cardiac referral centers. Clinical data was extracted from a national cardiac registry. Cost data was collected using mixed method of top-down and bottom-up approaches. Total hospitalization cost per PCI patient was summed up from the costs of ward admission and cardiac catheterization laboratory utilization. Clinical characteristics were compared with chi-square and independent t-test, while hospitalization length and cost were analyzed using Mann-Whitney test.

    RESULTS: The mean hospitalization cost was RM 12,117 (USD 3,366) at GH and RM 16,289 (USD 4,525) at TH. The higher cost at TH can be attributed to worse patients' comorbidities and cardiac status. In contrast, GH recorded a lower mean length of stay as more patients had same-day discharge, resulting in 29% reduction in mean cost of admission compared to TH. For both hospitals, PCI consumables accounted for the biggest proportion of total cost.

    CONCLUSIONS: The high PCI consumables cost highlighted the importance of cost-effective purchasing mechanism. Findings on the heterogeneity of the patients, treatment practice and hospitalization cost between TH and GH are vital for formulation of cost-saving strategies to ensure sustainable and equitable cardiac service in Malaysia.

    MeSH terms: Cross-Sectional Studies; Female; Hospitalization/economics*; Hospitals, General/economics*; Hospitals, Teaching/economics*; Humans; Length of Stay/economics; Malaysia; Male; Middle Aged; Treatment Outcome; Hospital Costs*; Percutaneous Coronary Intervention/economics*
  18. Naing C, Reid SA, Aung K
    BMC Infect Dis, 2017 01 05;17(1):29.
    PMID: 28056834 DOI: 10.1186/s12879-016-2145-3
    BACKGROUND: Network meta-analysis consists of simultaneous analysis of both direct comparisons of interventions within randomized controlled trials and indirect comparisons across trials based on a common comparator. In this paper, we aimed to characterise the conceptual understanding and the rationale for the use of network meta-analysis in assessing drug efficacy.

    METHODS: We selected randomized controlled trials, assessing efficacy of antibiotics for the treatment of leptospirosis as a case study. A pairwise meta-analysis was conducted using a random effect model, assuming that different studies assessed different but related treatment effects. The analysis was then extended to a network meta-analysis, which consists of direct and indirect evidence in a network of antibiotics trials, using a suite of multivariate meta-analysis routines of STATA (mvmeta command). We also assessed an assumption of 'consistency' that estimates of treatment effects from direct and indirect evidence are in agreement.

    RESULTS: Seven randomised controlled trials were identified for this analysis. These RCTs assessed the efficacy of antibiotics such as penicillin, doxycycline and cephalosporin for the treatment of human leptospirosis. These studies made comparisons between antibiotics (i.e. an antibiotic versus alternative antibiotic) in the primary study and a placebo, except for cephalosporin. These studies were sufficient to allow the creation of a network for the network meta-analysis; a closed loop in which three comparator antibiotics were connected to each other through a polygon. The comparison of penicillin versus the placebo has the largest contribution to the entire network (31.8%). The assessment of rank probabilities indicated that penicillin presented the greatest likelihood of improving efficacy among the evaluated antibiotics for treating leptospirosis.

    CONCLUSIONS: Findings suggest that network meta-analysis, a meta-analysis comparing multiple treatments, is feasible and should be considered as better precision of effect estimates for decisions when several antibiotic options are available for the treatment of leptospirosis.

    MeSH terms: Anti-Bacterial Agents/therapeutic use*; Cephalosporins/therapeutic use; Doxycycline/therapeutic use; Humans; Leptospirosis/drug therapy*; Penicillins/therapeutic use; Randomized Controlled Trials as Topic
  19. Lee DS, Abdullah KL, Subramanian P, Bachmann RT, Ong SL
    J Clin Nurs, 2017 Dec;26(23-24):4065-4079.
    PMID: 28557238 DOI: 10.1111/jocn.13901
    AIMS AND OBJECTIVES: To explore whether there is a correlation between critical thinking ability and clinical decision-making among nurses.

    BACKGROUND: Critical thinking is currently considered as an essential component of nurses' professional judgement and clinical decision-making. If confirmed, nursing curricula may be revised emphasising on critical thinking with the expectation to improve clinical decision-making and thus better health care.

    DESIGN: Integrated literature review.

    METHODS: The integrative review was carried out after a comprehensive literature search using electronic databases Ovid, EBESCO MEDLINE, EBESCO CINAHL, PROQuest and Internet search engine Google Scholar. Two hundred and 22 articles from January 1980 to end of 2015 were retrieved. All studies evaluating the relationship between critical thinking and clinical decision-making, published in English language with nurses or nursing students as the study population, were included. No qualitative studies were found investigating the relationship between critical thinking and clinical decision-making, while 10 quantitative studies met the inclusion criteria and were further evaluated using the Quality Assessment and Validity Tool. As a result, one study was excluded due to a low-quality score, with the remaining nine accepted for this review.

    RESULTS: Four of nine studies established a positive relationship between critical thinking and clinical decision-making. Another five studies did not demonstrate a significant correlation. The lack of refinement in studies' design and instrumentation were arguably the main reasons for the inconsistent results.

    CONCLUSIONS: Research studies yielded contradictory results as regard to the relationship between critical thinking and clinical decision-making; therefore, the evidence is not convincing. Future quantitative studies should have representative sample size, use critical thinking measurement tools related to the healthcare sector and evaluate the predisposition of test takers towards their willingness and ability to think. There is also a need for qualitative studies to provide a fresh approach in exploring the relationship between these variables uncovering currently unknown contributing factors.

    RELEVANCE TO CLINICAL PRACTICE: This review confirmed that evidence to support the existence of relationships between critical thinking and clinical decision-making is still unsubstantiated. Therefore, it serves as a call for nurse leaders and nursing academics to produce quality studies in order to firmly support or reject the hypothesis that there is a statistically significant correlation between critical thinking and clinical decision-making.

    MeSH terms: Clinical Decision-Making*; Humans; Leadership; Nurses/psychology*; Students, Nursing/psychology*; Thinking*
  20. Foo JC, Rahmat K, Mumin NA, Koh MT, Gan CS, Ramli N, et al.
    J Clin Neurosci, 2017 Sep 01.
    PMID: 28867361 DOI: 10.1016/j.jocn.2017.08.024
    We report a rare case of paediatric diphtheria complicated with encephalitis. A 6-year-old boy who did not receive his scheduled diptheria-tetanus-pertusis vaccination presented with one episode of generalised convulsive seizure. His illness was preceded by a 3day history of fever associated with enlarged exudative tonsils with a pseudomembrane. He was commenced on intravenous penicillin and oral erythromycin. However, he developed progressive encephalopathy with focal neurological deficit which required intubation on day 5 of illness. Throat swab polymerase chain reaction for diphtheria toxin A and B were positive and diphtheria antitoxin was given. Magnetic resonance imaging (MRI) of brain showed T2-weighted hyperintensities over the anterior cingulate gyri, insular cortex and cerebellum. This is the first reported MRI finding of diphtheric encephalitis. Our report highlights the importance of neuroimaging in diagnosing diphtheric encephalitis particularly in cases with unremarkable cerebrospinal findings.
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