74 research outputs found

    Influence of heteropoly acids on rat synaptic plasma membrane atp -ase activity

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    The in vitro influence of 12-tungstosilicic acid (WSiA) and 12-tungstophosporic acid (WPA) on Na+/K+_ATPase activity, using rat synaptic plasma membrane (SPM) as a model system was investigated. The half-maximum inhibition (IC50) of the enzyme activity was achieved with 5.80⋅ 10-5mol/L of WPA and 1.17⋅10-4 mol/L of WSiA. The both examined compounds showed a dose-dependent inhibitory effect on the enzyme activity in the concentration higher than 1 μmol/L

    Employing Gamma-Ray-Modified Carbon Quantum Dots to Combat a Wide Range of Bacteria

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    Nowadays, it is a great challenge to develop new medicines for treating various infectious diseases. The treatment of these diseases is of utmost interest to further prevent the development of multi-drug resistance in different pathogens. Carbon quantum dots, as a new member of the carbon nanomaterials family, can potentially be used as a highly promising visible-light-triggered antibacterial agent. In this work, the results of antibacterial and cytotoxic activities of gamma-ray-irradiated carbon quantum dots are presented. Carbon quantum dots (CQDs) were synthesized from citric acid by a pyrolysis procedure and irradiated by gamma rays at different doses (25, 50, 100 and 200 kGy). Structure, chemical composition and optical properties were investigated by atomic force microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, UV-Vis spectrometry and photoluminescence. Structural analysis showed that CQDs have a spherical-like shape and dose-dependent average diameters and heights. Antibacterial tests showed that all irradiated dots had antibacterial activity but CQDs irradiated with dose of 100 kGy had antibacterial activity against all seven pathogen-reference bacterial strains. Gamma-ray-modified CQDs did not show any cytotoxicity toward human fetal-originated MRC-5 cells. Moreover, fluorescence microscopy showed excellent cellular uptake of CQDs irradiated with doses of 25 and 200 kGy into MRC-5 cells

    Ambient light induced antibacterial action of curcumin/graphene nanomesh hybrids

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    Curcumin and its derivates are well-known for their different biological activities including antibacterial. On the other hand there are controversial reports concerning the antibacterial potential of graphene and, in particular, graphene oxide. In this study we have reported for the first time the antibacterial activity of curcumin/graphene nanomesh hybrids under ambient light conditions. The graphene nanomesh was synthesized by electrochemical exfoliation of highly oriented pyrolytic graphite in 1 M solution of ammonium persulfate and further functionalized by curcumin. Identical values of minimum inhibitory concentration (1 mg mL(-1)) were determined for pure curcumin and curcumin/graphene nanomesh hybrids toward Staphylococcus aureus. All tested samples had more pronounced antibacterial activity against Gram positive bacteria, Staphylococcus aureus compared to Escherichia coli as a representative of Gram negative strains. The poor antibacterial potential of exfoliated graphene improves significantly by the functionalization with curcumin, which allows for its usage as a antibacterial coating

    Using hospital discharge data for determining neonatal morbidity and mortality: a validation study

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    <p>Abstract</p> <p>Background</p> <p>Despite widespread use of neonatal hospital discharge data, there are few published reports on the accuracy of population health data with neonatal diagnostic or procedure codes. The aim of this study was to assess the accuracy of using routinely collected hospital discharge data in identifying neonatal morbidity during the birth admission compared with data from a statewide audit of selected neonatal intensive care (NICU) admissions.</p> <p>Methods</p> <p>Validation study of population-based linked hospital discharge/birth data against neonatal intensive care audit data from New South Wales, Australia for 2,432 babies admitted to NICUs, 1994–1996. Sensitivity, specificity and positive predictive values (PPV) with exact binomial confidence intervals were calculated for 12 diagnoses and 6 procedures.</p> <p>Results</p> <p>Sensitivities ranged from 37.0% for drainage of an air leak to 97.7% for very low birthweight, specificities all exceeded 85% and PPVs ranged from 70.9% to 100%. In-hospital mortality, low birthweight (≤1500 g), retinopathy of prematurity, respiratory distress syndrome, meconium aspiration, pneumonia, pulmonary hypertension, selected major anomalies, any mechanical ventilation (including CPAP), major surgery and surgery for patent ductus arteriosus or necrotizing enterocolitis were accurately identified with PPVs over 92%. Transient tachypnea of the newborn and drainage of an air leak had the lowest PPVs, 70.9% and 83.6% respectively.</p> <p>Conclusion</p> <p>Although under-ascertained, routinely collected hospital discharge data had high PPVs for most validated items and would be suitable for risk factor analyses of neonatal morbidity. Procedures tended to be more accurately recorded than diagnoses.</p

    Trends in Outcomes for Neonates Born Very Preterm and Very Low Birth Weight in 11 High-Income Countries

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    Objective To evaluate outcome trends of neonates born very preterm in 11 high-income countries participating in the International Network for Evaluating Outcomes of neonates. Study design In a retrospective cohort study, we included 154 233 neonates admitted to 529 neonatal units between January 1, 2007, and December 31, 2015, at 24(0/7) to 31(6/7) weeks of gestational age and birth weight <1500 g. Composite outcomes were in-hospital mortality or any of severe neurologic injury, treated retinopathy of prematurity, and bronchopulmonary dysplasia (BPD); and same composite outcome excluding BPD. Secondary outcomes were mortality and individual morbidities. For each country, annual outcome trends and adjusted relative risks comparing epoch 2 (2012-2015) to epoch 1 (2007-2011) were analyzed. Results For composite outcome including BPD, the trend decreased in Canada and Israel but increased in Australia and New Zealand, Japan, Spain, Sweden, and the United Kingdom. For composite outcome excluding BPD, the trend decreased in all countries except Spain, Sweden, Tuscany, and the United Kingdom. The risk of composite outcome was lower in epoch 2 than epoch 1 in Canada (adjusted relative risks 0.78; 95% CI 0.74-0.82) only. The risk of composite outcome excluding BPD was significantly lower in epoch 2 compared with epoch 1 in Australia and New Zealand, Canada, Finland, Japan, and Switzerland. Mortality rates reduced in most countries in epoch 2. BPD rates increased significantly in all countries except Canada, Israel, Finland, and Tuscany. Conclusions In most countries, mortality decreased whereas BPD increased for neonates born very preterm

    Comparing CRIB-II and SNAPPE-II as mortality predictors for very preterm infants

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    © 2014 Paediatrics and Child Health Division (Royal Australasian College of Physicians). Aims This article compares the severity of illness scoring systems clinical risk index for babies (CRIB)-II and score for neonatal acute physiology with perinatal extension (SNAPPE)-II for discriminatory ability and goodness of fit in the same cohort of babies of less than 32 weeks gestation and aims to provide validation in the Australian population. Methods CRIB-II and SNAPPE-II scores were collected on the same cohort of preterm infants born within a 2-year period, 2003 and 2004. The discriminatory ability of each score was assessed by the area under the receiver operator characteristic curve, and goodness of fit was assessed by the Hosmer-Lemeshow (HL) test. The outcome measure was in-hospital mortality. A multivariate logistic regression model was tested for perinatal variables that might add to the risk of in-hospital mortality. Results Data for both scores were available for 1607 infants. Both scores had good discriminatory ability (CRIB-II area under the curve 0.913, standard error (SE) 0.014; SNAPPE-II area under the curve 0.907, SE 0.012) and adequate goodness of fit (HL χ2 = 11.384, 8 degrees of freedom, P = 0.183 for CRIB-II; HL χ2 = 4.319, 7 degrees of freedom, P = 0.742 for SNAPPE-II). The multivariate model did not reveal other significant variables. Conclusions Both severity of illness scores are ascertained during the first 12 h of life and perform similarly. Both can facilitate risk-adjusted comparisons of mortality and quality of care after the first post-natal 12 h. CRIB-II scores have the advantage of being simpler to collect and calculate
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