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Gecko-Inspired Biocidal Organic Nanocrystals Initiated from a Pencil-Drawn Graphite Template
The biocidal properties of gecko skin and cicada wings have inspired the synthesis of synthetic surfaces decorated with high aspect ratio nanostructures that inactivate microorganisms. Here, we investigate the bactericidal activity of oriented zinc phthalocyanine (ZnPc) nanopillars grown using a simple pencil-drawn graphite templating technique. By varying the evaporation time, nanopillars initiated from graphite that was scribbled using a pencil onto silicon substrates were optimized to yield a high inactivation of the Gram-negative bacteria, Escherichia coli. We next adapted the procedure so that analogous nanopillars could be grown from pencil-drawn graphite scribbled onto stainless steel, flexible polyimide foil, and glass substrates. Time-dependent bacterial cytotoxicity studies indicate that the oriented nanopillars grown on all four substrates inactivated up to 97% of the E. coli quickly, in 15 min or less. These results suggest that organic nanostructures, which can be easily grown on a broad range of substrates hold potential as a new class of biocidal surfaces that kill microbes quickly and potentially, without spreading antibiotic-resistance genes
Adult systemic cat scratch disease associated with therapy for hepatitis C
BACKGROUND: We describe the first case of systemic cat scratch disease in a patient receiving peginterferon α-2a and ribavirin for treatment of hepatitis C. Cases of adult systemic CSD are extremely infrequent and immunomodulatory treatment for hepatitis C has been associated with aberrant host responses to common pathogens. CASE PRESENTATION: A 52 year old man being treated for hepatitis C presented with diffuse lymphadenopathy, weight loss, fevers and splenic lesions. Symptoms were initially confused with adverse effects of his regimen, delaying recognition of his infection. Diagnostic investigation, including histopathology, microbiology and serologic parameters, confirmed that his illness was due to disseminated cat scratch disease with Bartonella henselae. CONCLUSION: Disseminated CSD is exceptionally rare in adults. We describe the first case of disseminated cat scratch disease associated with peginterferon α and ribavirin to alert clinicians of the need to be aware of unusual manifestations of common infections in this population
Analysis of MEFV exon methylation and expression patterns in familial Mediterranean fever
<p>Abstract</p> <p>Background</p> <p>MEFV mutations and decreased expression level of the gene are related to FMF pathology. DNA methylation at CpG islands is a well-known mechanism for transcriptional silencing. MEFV has a CpG island, spanning a part of the first intron and the whole of the second exon of the gene covering 998 bp region. Here, we tested the hypothesis that the MEFV transcript level in FMF patients correlates with its methylation level, and methylation, by allowing transcription silencing, has a role in FMF ethiopathogenesis.</p> <p>Methods</p> <p>The study group was composed of pediatric FMF patients (N = 51) and age-gender matched healthy controls (N = 21). The relative expression level of MEFV was assessed via quantitative real-time PCR (qRT-PCR) and bisulfite sequencing (BS) was performed to analyse the methylation level quantitatively.</p> <p>Results</p> <p>MEFV expression in FMF patients were decreased compared to healthy controls (<it>P </it>= 0.031). Methylation level of exon 2 of MEFV was found to be slightly higher in FMF patients compared to healthy controls (76% versus 74%) (<it>P </it>= 0.049). The expression level of the MEFV was negatively correlated with the methylation level of the CpG island in both FMF and healthy controls groups (cor = -0.29, <it>P </it>= 0.041) but more so in the FMF only group (cor = -0.36, <it>P </it>= 0.035).</p> <p>Conclusions</p> <p>In this study, the relation between reduced MEFV expression level and FMF was confirmed. Observed slight increase in methylation in FMF patients, and correlation of methylation with expression might be indicative of its role in FMF, however a larger dataset is needed to confirm our preliminary findings.</p
Chest and occipito-frontal circumference measurements in the detection of low birth weight among Nigerian newborns of Igbo ethnicity
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS
The term biodiesel means the monoalkyl esters of long-chain fatty acids made from biolipids such as vegetable oils, animal fats, or algae. Chemical reactivity of biodiesel can be divided into oxidative and thermal instability. Many of the biolipids contain polyunsaturated fatty acid chains in that their double bonds have high chemical reactivity. The oxidative and thermal degradation occurs on the double bonds of unsaturated aliphatic carbons chains in biolipids. Oxidation of biodiesel results in the formation of hydroperoxides. The formation of the hydroperoxide follows a well-known peroxidation chain mechanism. The olefinic unsaturated fatty acid oxidation is a multi-step reaction process where primary products (conjugated diene hydroperoxides) decompose and chemically interact with each other to form numerous secondary oxidation products. The oxidative and thermal instability are determined by the amount and configuration of the olefinic unsaturation on the fatty acid chains. The viscosity of biodiesel increases with the increase of thermal degradation degree due to the trans-isomer formation on double bonds. The decomposition of biodiesel and its corresponding fatty acids linearly increases from 293 K to 625 K. The densities of biodiesel fuels decreased linearly with temperatures from 293 K to 575 K. The combustion heat of biodiesel partially decreases with the increase of thermal degradation degree
Deacidification of high acid olive oil by immobilized lipase
WOS: A1996VQ52100012The acidity reduction of high acid oils prior to refining could be an attractive application for industry. In this study the enzymatic deacidification degummed and dewaxed olive oil with a high free fatty acid content, catalysed by an immobilized lipase was optimzed (Novozym 435). The optimum amount of substrate for synthesizing trigliycerides was the necessary stoichiometric amount of fatty acid and glycerol. The mixing was performed with a mechanical stirrer and the dehydration was performed by vacuum pump or by bubbling dry nitrogen. The dehydration rate was faster than the deacidification rate. The four parameters chosen for this experimental plan: pressure! temperature, and the amounts of glycerol and enzyme in the reaction mixture. The use of glycerol more than theortical amount did not affect the rate of deacidification. The stoichiometric amount of glycerol was sufficient for the deacidification of high acid olive oil. Maintaining low pressure is very important for the removal of water which is formed during the esterification reaction. Either, the reaction is conducted at 20 mm Hg or the dehydration is performed by bubbling dry nitrogen. The optimum amount of immobilized enzyme necessary for the deacidification reaction was determined and 10:1 ratio of oil: immobilized enzyme appeared to be satisfactory. The effect of temperature on the deacidification of high acid olive oil was investigated (between 40-70 degrees C). The reaction temperature influenced the rate of deacidification. The optimum operation temperature was found to be 60 degrees C. At 70 degrees C the deacidification decreased with increasing incubation time due to enzyme deactivation occuring at this temperature
Concentrations of toxic metals and trace elements in the meconium of newborns from an industrial city
Objective: To investigate fetal exposure to toxic metals [lead (Pb), cadmium (Cd)] and fetal levels of trace elements [zinc (Zn), copper (Cu), and iron (Fe)] in newborns from an industrial city. Relationships between meconium mineral contents and parental occupation and location of residence were also tested. Method. The meconium mineral contents of 117 healthy newborn infants were measured by flame atomic absorption spectrophotometer. Results:The median concentrations (interquartile range) of toxic metals and trace elements in the meconium were as follows: Pb: 46.5 (1,399) mu g/g dry weight (wt), Cd: 2.3 (55.6) mu g/g dry wt; Zn: 234 (3,049) mu g/g dry wt; Cu: 11.8 (818.7) mu g/g dry wt, and Fe 105 (2,980) mu g/g dry wt. All the meconium samples contained both toxic metals and trace elements. The proportions of trace elements in the meconium samples with concentration higher than 100 mu g/g dry wt of the substances tested were Zn 90%, Cu 64%, and Fe 53%. There were significantly positive correlations between the concentrations of toxic metals and trace elements. Also there were positive correlations between the levels of Zn, Fe, and parental occupations, and between the level of Fe and location of residence of the parents (proximity to the petroleum refinery or the dye industries). Conclusion:All the meconium samples were positive for toxic metals, and thus may reflect environmental pollution in the city. The occupation environments and the location of the family residence are linked with levels of trace elements in meconium. Copyright (c) 2006 S. Karger AG, Basel
The tuberculin response in juvenile idiopathic arthritis patients vaccinated with bacilliuscalmette-guerin
Analysis of MEFV exon methylation and expression patterns in familial Mediterranean fever
Background: MEFV mutations and decreased expression level of the gene are related to FMF pathology. DNA methylation at CpG islands is a well-known mechanism for transcriptional silencing. MEFV has a CpG island, spanning a part of the first intron and the whole of the second exon of the gene covering 998 bp region. Here, we tested the hypothesis that the MEFV transcript level in FMF patients correlates with its methylation level, and methylation, by allowing transcription silencing, has a role in FMF ethiopathogenesis
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