8 research outputs found
Poly(neutral red) based hydrogen peroxide biosensor for chromium determination by inhibition measurements
Amperometric hydrogen peroxide enzyme inhibition biosensors based on horseradish peroxidase (HRP) immobilised on electropolymerised neutral red (NR) or directly on the surface of carbon film electrodes (CFE) have been successfully applied to the determination of toxic Cr(III) and Cr(VI). Parameters influencing the performance of the biosensor including the enzyme immobilisation method, the amount of hydrogen peroxide, applied potential and electrolyte pH were optimised. The inhibition of horseradish peroxidase by the chromium species was studied under the optimised conditions. Results from the quantitative analysis of chromium ions are discussed in terms of detection limit, linear range and sensitivity. The HRP kinetic interactions reveal mixed binding of Cr(III) with I50 = 3.8 μM and inhibition binding constant Ki = 11.3 μM at HRP/PNR/CFE biosensors and uncompetitive binding of Cr(VI) with I50 = 3.9 μM and Ki = 0.78 μM at HRP/CFE biosensors in the presence of H2O2 substrate. Interferences from other heavy metal ions were studied and the inhibition show very good selectivity towards Cr(III) and Cr(VI)
Poly(neutral red) based hydrogen peroxide biosensor for chromium determination by inhibition measurements
A database for screening and registering late onset Pompe disease in Turkey
The aim of this study was to search for the frequency of late onset Pompe disease (LOPD) among patients who had a myopathy with unknown diagnosis registered in the pre-diagnostic part of a novel registry for LOPD within a collaborative study of neurologists working throughout Turkey. Included in the study were 350 patients older than 18 years who have a myopathic syndrome without a proven diagnosis by serum creatine kinase (CK) levels, electrodiagnostic studies, and/or muscle pathology, and/or genetic tests for myopathies other than LOPD. Acid alpha glucosidase (GAA) in dried blood spot was measured in each patient at two different university laboratories. LOPD was confirmed by mutation analysis in patients with decreased GAA levels from either both or one of the laboratories. Pre-diagnostic data, recorded by 45 investigators from 32 centers on 350 patients revealed low GAA levels in a total of 21 patients; from both laboratories in 6 and from either one of the laboratories in 15. Among them, genetic testing proved LOPD in 3 of 6 patients and 1 of 15 patients with decreased GAA levels from both or one of the laboratories respectively. Registry was transferred to Turkish Neurological Association after completion of the study for possible future use and development. Our collaborative study enabled collection of a considerable amount of data on the registry in a short time. GAA levels by dried blood spot even from two different laboratories in the same patient may not prove LOPD. LOPD seemed to be rarer in Turkey than in Europe. © 2017 Elsevier B.V
A database for screening and registering late onset Pompe disease in Turkey
The aim of this study was to search for the frequency of late onset Pompe disease (LOPD) among patients who had a myopathy with unknown diagnosis registered in the pre-diagnostic part of a novel registry for LOPD within a collaborative study of neurologists working throughout Turkey. Included in the study were 350 patients older than 18 years who have a myopathic syndrome without a proven diagnosis by serum creatine kinase (CK) levels, electrodiagnostic studies, and/or muscle pathology, and/or genetic tests for myopathies other than LOPD. Acid alpha glucosidase (GAA) in dried blood spot was measured in each patient at two different university laboratories. LOPD was confirmed by mutation analysis in patients with decreased GAA levels from either both or one of the laboratories. Pre-diagnostic data, recorded by 45 investigators from 32 centers on 350 patients revealed low GAA levels in a total of 21 patients; from both laboratories in 6 and from either one of the laboratories in 15. Among them, genetic testing proved LOPD in 3 of 6 patients and 1 of 15 patients with decreased GAA levels from both or one of the laboratories respectively. Registry was transferred to Turkish Neurological Association after completion of the study for possible future use and development. Our collaborative study enabled collection of a considerable amount of data on the registry in a short time. GAA levels by dried blood spot even from two different laboratories in the same patient may not prove LOPD. LOPD seemed to be rarer in Turkey than in Europe. © 2017 Elsevier B.V
Thermally stratified squeezed flow between two vertical Riga plates with no slip conditions
Global Asthma Network survey suggests more national asthma strategies could reduce burden of asthma
Background Several countries or regions within countries have an effective national asthma strategy resulting in a reduction of the large burden of asthma to individuals and society. There has been no systematic appraisal of the extent of national asthma strategies in the world. Methods The Global Asthma Network (GAN) undertook an email survey of 276 Principal Investigators of GAN centres in 120 countries, in 2013–2014. One of the questions was: “Has a national asthma strategy been developed in your country for the next five years? For children? For adults?”. Results Investigators in 112 (93.3%) countries answered this question. Of these, 26 (23.2%) reported having a national asthma strategy for children and 24 (21.4%) for adults; 22 (19.6%) countries had a strategy for both children and adults; 28 (25%) had a strategy for at least one age group. In countries with a high prevalence of current wheeze, strategies were significantly more common than in low prevalence countries (11/13 (85%) and 7/31 (22.6%) respectively, p < 0.001). Interpretation In 25% countries a national asthma strategy was reported. A large reduction in the global burden of asthma could be potentially achieved if more countries had an effective asthma strategy. © 2017 SEICA
Global Asthma Network survey suggests more national asthma strategies could reduce burden of asthma
Background Several countries or regions within countries have an effective national asthma strategy resulting in a reduction of the large burden of asthma to individuals and society. There has been no systematic appraisal of the extent of national asthma strategies in the world. Methods The Global Asthma Network (GAN) undertook an email survey of 276 Principal Investigators of GAN centres in 120 countries, in 2013–2014. One of the questions was: “Has a national asthma strategy been developed in your country for the next five years? For children? For adults?”. Results Investigators in 112 (93.3%) countries answered this question. Of these, 26 (23.2%) reported having a national asthma strategy for children and 24 (21.4%) for adults; 22 (19.6%) countries had a strategy for both children and adults; 28 (25%) had a strategy for at least one age group. In countries with a high prevalence of current wheeze, strategies were significantly more common than in low prevalence countries (11/13 (85%) and 7/31 (22.6%) respectively, p < 0.001). Interpretation In 25% countries a national asthma strategy was reported. A large reduction in the global burden of asthma could be potentially achieved if more countries had an effective asthma strategy. © 2017 SEICA