•Counter-current chromatography (CCC) was used to collect ganglioside fractions.•The selected CCC solvent system was 2:4:3:8 butanol/MTBE/acetonitrile/H2O.•0.5% (v/v) acetic acid was added to the ...lower phase in dual-mode elution CCC.•CCC separated mg levels of (d36:1) & (d38:1) homologues of porcine GM1, GD1a & GD1b.•The purity of ganglioside fractions was estimated using LC-MS/MS.
Gangliosides play critical roles in the development of many progressive diseases. Due to their structural diversity, efficient methods are needed to separate individual gangliosides for studies of their functions, and for use as standards in the analysis of ganglioside mixtures. This proof-of-concept study reports a useful analytical-semi-preparative scale counter-current chromatography (CCC) enrichment of multiple ganglioside homologues of various species and classes at the milligram level.
Since few individual ganglioside standards were available, this research aimed to achieve analytical-semi-preparative scale separation of gangliosides by differences in saccharide monomer compositions (classes), their arrangements (species), or ceramide compositions (homologues), using CCC. The solvent system composition, addition of solvent modifiers, and elution modes were all adjusted to separate porcine gangliosides, mainly GM1 (d36:1), GD1a (d36:1), GD1b (d36:1) and their (d38:1) homologues as a demonstration. The eluted compounds were analyzed by flow-injection analysis (FIA)-MS and LC-MS/MS.
A two-phase solvent system, consisting of butanol/methyl t-butyl ether/acetonitrile/water at a ratio of 2:4:3:8 (v/v/v/v) with 0.5% (v/v) acetic acid added to the lower phase, was used to separate mg-levels of porcine gangliosides under dual-mode elution. The relative abundances of the above 6 gangliosides increased from 10 to 21% in the ganglioside extract to 55–73% in the collected fractions through the purification.
The study presents the results of measuring the resilience of high school students. The main goal is to find whether there is a link between the resilience of students and preferred coping ...strategies. Quantitative research was subsequently conducted with students in the 2nd and 3rd years of secondary schools. The research included a questionnaire survey in which students were presented with two questionnaires. The first questionnaire was self-designed and aimed to assess the level of resilience; the second standardized questionnaire focused on the preferred choice of coping strategies. Responses were received from a total of 516 respondents. The data were evaluated using the tools of descriptive statistics. The results showed that pupils' resilience is generally at a good level. In addition, five key factors improving and lowering resilience were identified. Furthermore, five preferred strategies and five strategies that students prefer to avoid when dealing with problem situations were identified. At the same time, a direct correlation between the effort to take an active approach to solve problems and the degree of resilience was observed; this is considered to be the main outcome of the study.
The study presents the results of measuring the resilience of high school students. The main goal is to find whether there is a link between the resilience of students and preferred coping ...strategies. Quantitative research was subsequently conducted with students in the 2nd and 3rd years of secondary schools. The research included a questionnaire survey in which students were presented with two questionnaires. The first questionnaire was self-designed and aimed to assess the level of resilience; the second standardized questionnaire focused on the preferred choice of coping strategies. Responses were received from a total of 516 respondents. The data were evaluated using the tools of descriptive statistics. The results showed that pupils' resilience is generally at a good level. In addition, five key factors improving and lowering resilience were identified. Furthermore, five preferred strategies and five strategies that students prefer to avoid when dealing with problem situations were identified. At the same time, a direct correlation between the effort to take an active approach to solve problems and the degree of resilience was observed; this is considered to be the main outcome of the study.
Inverse ECG imaging methods typically require 32-250 leads to create body surface potential maps (BSPM), limiting their routine clinical use. This study evaluated the accuracy of PaceView inverse ECG ...method to localize the left or right ventricular (LV and RV, respectively) pacing leads using either a 99-lead BSPM or the 12-lead ECG. A 99-lead BSPM was recorded in patients with cardiac resynchronization therapy (CRT) during sinus rhythm and sequential LV/RV pacing. The non-contrast CT was performed to localize precisely both ECG electrodes and CRT leads. From a BSPM, nine signals were selected to obtain the 12-lead ECG. Both BSPM and 12-lead ECG were used to localize the RV and LV lead, and the localization error was calculated. Consecutive patients with dilated cardiomyopathy, previously implanted with a CRT device, were enrolled (n = 19). The localization error for the RV/LV lead was 9.0 IQR 4.8-13.6 / 7.7 IQR 0.0-10.3 mm using the 12-lead ECG and 9.1 IQR 5.4-15.7 / 9.8 IQR 8.6-13.1 mm for the BSPM. Thus, the noninvasive lead localization using the 12-lead ECG was accurate enough and comparable to 99-lead BSPM, potentially increasing the capability of 12-lead ECG for the optimization of the LV/RV pacing sites during CRT implant or for the most favorable programming.
Plastics are mixtures of organic polymers that play a major role in environmental contamination worldwide. One way to reduce the waste arising from the use of plastics, especially disposable ones, ...can be to produce environmentally friendly cutlery. The aim of the work was the production of biodegradable spoons and evaluation of their texture, antioxidant activities and total polyphenols content. The spoons were made from a combination of the following ingredients: water, grape, proso millet, wheat, xanthan and palm oil in different concentrations. The samples were baked at 180 or 240 °C, some spoons were dried in a fruit dehydrator. According to the results of the analysis, a spoon prepared from a mixture of all three flours and with the addition of xanthan appears to be the most suitable replacement for plastic cutlery. This spoon showed high strength and antioxidant activity. It was confirmed that the use of grape flour has a beneficial effect on the nutritional profile of the experimentally produced biodegradable spoons.
El artículo se enfoca en los cambios en la vida de las mujeres lacandonas contemporáneas. Analiza cómo se han modificado el modo de la vida, las costumbres y las relaciones de la mujer dentro de las ...propias familias pero también dentro de la sociedad y la comunidad. El objetivo es mostrar los cambios reflejados en la vida de las mujeres de tres generaciones. El estudio está basado en las etnografías disponibles combinadas con el propio trabajo de campo realizado en las comunidades Lacanjá y Nahá en los años 2008 y 2009.
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