Mobility limitations Dotaz Zobrazit nápovědu
In the second part of this study, a systematic comparison was made between two ion fragmentation acquisition modes, namely data-independent acquisition (DIA) and DIA with ion mobility spectrometry (IMS) technology. These two approaches were applied to the analysis of 192 doping agents in urine. Group I included 102 compounds such as stimulants, diuretics, narcotics, and β2-agonists, while Group II contained 90 compounds included steroids, glucocorticoids, and hormone and metabolic modulators. Important method parameters were examined and compared, including the fragmentation, sensitivity, and assignment capability with the minimum occurrence of false positive hits. The results differed between Group I and II in number of detected fragments when exploring the MS/MS spectra. In Group I only 13%, while in the Group II 64% of the substances had a higher number of fragments in DIA-IMS mode vs. DIA. In terms of sensitivity, the performance of the two modes with and without activated IMS dimension was identical for about 50% of the doping agents. The sensitivity was higher without IMS, i.e. in simple DIA mode, for 20-40% of remaining doping agents. Despite this sensitivity reduction with IMS, 82% of compounds from both Groups met the minimum required performance level (MRPL) criteria of the World Anti-Doping Agency (WADA) when the DIA-IMS mode was applied. Automated data processing is important in routine doping analysis. Therefore, processing methods were optimized and evaluated for the prevalence of false peak assignments by analysing the target substances at different concentrations in urine samples. Overall, a significantly higher number of misidentified compounds was observed in Group II, with an almost 2-fold higher number of misidentifications in DIA compared to DIA-IMS. This result highlights the benefit of the IMS dimension to reduce the rate of false positive in screening analysis. The optimized UHPLC-IM-HRMS method was finally applied to the analysis of urine samples from administration studies including nine doping agents from both Groups. However, to limit the number of interferences from the biological matrix, an emphasis is needed on the adequate settings of the data processing method.
- Klíčová slova
- Anti-Doping analysis, Collision cross section, High resolution mass spectrometry, Ion mobility spectrometry, Ultra-high performance liquid chromatography,
- MeSH
- doping ve sportu * MeSH
- glukokortikoidy MeSH
- iontová mobilní spektrometrie * MeSH
- narkotika MeSH
- steroidy MeSH
- tandemová hmotnostní spektrometrie MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- glukokortikoidy MeSH
- narkotika MeSH
- steroidy MeSH
Silymarin, milk thistle (Silybum marianum) extract, contains a mixture of mostly isomeric bioactive flavonoids and flavonolignans that are extensively studied, especially for their possible liver-protective and anticancer effects. Because of the differing bioactivities of individual isomeric compounds, characterization of their proportion in a mixture is highly important for predicting its effect on health. However, because of silymarin's complexity, this is hardly feasible by common analytical techniques. In this work, ultraperformance liquid chromatography coupled with drift tube ion mobility spectrometry and quadrupole time-of-flight mass spectrometry was used. Eleven target silymarin compounds (taxifolin, isosilychristin, silychristins A and B, silydianin, silybins A and B, 2,3-cis-silybin B, isosilybins A and B and 2,3-dehydrosilybin) and five unknown flavonolignan isomers detected in the milk thistle extract were fully separated in a 14.5-min analysis run. All the compounds were characterized on the basis of their accurate mass, retention time, drift time, collision cross section and fragmentation spectra. The quantitative approach based on evaluation of the ion mobility data demonstrated lower detection limits, an extended linear range and total separation of interferences from the compounds of interest compared with the traditional approach based on evaluation of liquid chromatography-quadrupole time-of-flight mass spectrometry data. The following analysis of a batch of milk thistle-based food supplements revealed significant variability in the silymarin pattern, especially in the content of silychristin A and silybins A and B. This newly developed method might have high application potential, especially for the characterization of materials intended for bioactivity studies in which information on the exact silymarin composition plays a crucial role. Graphical Abstract.
- Klíčová slova
- Collision cross section, Drift tube ion mobility high-resolution mass spectrometry, Milk thistle, Silybum marianum, Silymarin, Ultraperformance liquid chromatography,
- MeSH
- flavonolignany analýza izolace a purifikace MeSH
- hmotnostní spektrometrie metody MeSH
- iontová mobilní spektrometrie metody MeSH
- isomerie MeSH
- ostropestřec mariánský chemie MeSH
- silymarin analýza izolace a purifikace MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- flavonolignany MeSH
- silymarin MeSH
In this series of two papers, 192 doping agents belonging to the classes of stimulants, narcotics, cannabinoids, diuretics, β2-agonists, β-blockers, anabolic agents, and hormone and metabolic modulators were investigated, with the aim to assess the benefits and limitations of ion mobility spectrometry (IMS) in combination with ultra-high performance liquid chromatography (UHPLC) and high resolution mass spectrometry (HRMS) in anti-doping analysis. In this first part, a generic UHPLC-IM-HRMS method was successfully developed to analyze these 192 doping agents in standard solutions and urine samples, and an exhaustive database including retention times, TWCCSN2 values, and m/z ratios was constructed. Urine samples were analyzed using either a simple "dilute and shoot" procedure or a supported liquid-liquid extraction (SLE) procedure, depending on the physicochemical properties of the compounds and sensitivity criteria established by the World Anti-Doping Agency (WADA) as the minimum required performance levels (MRPL). Then, the precision of the generic UHPLC-IM-HRMS method was assessed as intraday, interday as well as interweek variation of UHPLC retention times and TWCCSN2 values, for which RSD the values were always lower than 2% in urine samples. The possibility to filter MS data using IMS dimension was also investigated, and in average, the application of IMS filtration provided low energy MS spectra with 86% less interfering peaks in both standard and urine samples. Therefore, the filtered MS spectra allowed for an easier interpretation and a lower risk of false positive result interpretations. Finally, IMS also offers additional selectivity to the UHPLC-HRMS enabling to separate isobaric and isomeric substances. Among the selected set of 192 doping agents, there were 30 pairs of isobaric or isomeric compounds, and only two pairs could not be resolved under the developed conditions. This illustrates the potential of adding ion mobility to UHPLC-HRMS in anti-doping analyses.
- Klíčová slova
- Collision cross section, Doping analysis, High resolution mass spectrometry, Ion mobility spectrometry, Ultra-high performance liquid chromatography,
- MeSH
- anabolika * MeSH
- doping ve sportu * MeSH
- hmotnostní spektrometrie MeSH
- iontová mobilní spektrometrie MeSH
- odhalování abúzu drog MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- anabolika * MeSH
Parallel reaction monitoring (PRM) has emerged as a popular approach for targeted protein quantification. With high ion utilization efficiency and first-in-class acquisition speed, the timsTOF Pro provides a powerful platform for PRM analysis. However, sporadic chromatographic drift in peptide retention time represents a fundamental limitation for the reproducible multiplexing of targets across PRM acquisitions. Here, we present PRM-LIVE, an extensible, Python-based acquisition engine for the timsTOF Pro, which dynamically adjusts detection windows for reproducible target scheduling. In this initial implementation, we used iRT peptides as retention time standards and demonstrated reproducible detection and quantification of 1857 tryptic peptides from the cell lysate in a 60 min PRM-LIVE acquisition. As an application in functional proteomics, we use PRM-LIVE in an activity-based protein profiling platform to assess binding selectivity of small-molecule inhibitors against 220 endogenous human kinases.
- MeSH
- hmotnostní spektrometrie MeSH
- iontová mobilní spektrometrie * MeSH
- lidé MeSH
- peptidy MeSH
- proteiny MeSH
- proteomika * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Názvy látek
- peptidy MeSH
- proteiny MeSH
Permanently charged and ionizable organic compounds (IOC) are a large and diverse group of compounds belonging to many contaminant classes, including pharmaceuticals, pesticides, industrial chemicals, and natural toxins. Sorption and mobility of IOCs are distinctively different from those of neutral compounds. Due to electrostatic interactions with natural sorbents, existing concepts for describing neutral organic contaminant sorption, and by extension mobility, are inadequate for IOC. Predictive models developed for neutral compounds are based on octanol-water partitioning of compounds (Kow) and organic-carbon content of soil/sediment, which is used to normalize sorption measurements (KOC). We revisit those concepts and their translation to IOC (Dow and DOC) and discuss compound and soil properties determining sorption of IOC under water saturated conditions. Highlighting possible complementary and/or alternative approaches to better assess IOC mobility, we discuss implications on their regulation and risk assessment. The development of better models for IOC mobility needs consistent and reliable sorption measurements at well-defined chemical conditions in natural porewater, better IOC-, as well as sorbent characterization. Such models should be complemented by monitoring data from the natural environment. The state of knowledge presented here may guide urgently needed future investigations in this field for researchers, engineers, and regulators.
- Klíčová slova
- anion, cation, contaminant fate, environmental risk assessment, ionizable organic compound, sorption model, zwitterion,
- MeSH
- adsorpce MeSH
- látky znečišťující půdu * analýza MeSH
- organické látky * chemie MeSH
- půda MeSH
- uhlík chemie MeSH
- voda chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- látky znečišťující půdu * MeSH
- organické látky * MeSH
- půda MeSH
- uhlík MeSH
- voda MeSH
PURPOSE OF STUDY Based on the selected criteria the study presents the evaluation of data of patients who underwent a surgery for proximal femoral fracture at the Department of Orthopaedic Trauma of the 1 st Faculty of Medicine and Military University Hospital Prague in the period 2013-2016. The paper aimed to determine whether there are any differences in proximal femoral fractures depending on the selected criteria. MATERIAL AND METHODS The study comprised 805 patients (562 women and 243 men) older than 21 years with proximal femoral fractures who were treated between January 1, 2013 and December 31, 2016. In the study, the patient s data on gender, age, a type of fracture (according to the AO classification), a level of mobility, time of injury and month of injury were analysed. The data was evaluated using the methods of descriptive statistics, one-way analysis of variance, two-way analysis by ANOVA and by following select POST-HOC test (Fisher LSD test) were utilized, 95% confidence interval was selected . RESULTS In the group of treated patients, the men were outnumbered by women (70% vs. 30%). In women the fractures occurred at a significantly (p < 0.001) older age (82 years) compared to men (77 years). Until the 8 th decade the fractures in men dominated, while from the 9th decade the fractures were more frequent in women. A sharp increase in the number of fractures in women was reported exactly in the 9th decade (56% of the total number of fractures in women). The group of women showed a significant difference (p = 0.027) between the age of femoral neck fractures and the age of trochanteric femoral fractures (80 years vs. 84 years). In both genders intracapsular and pertrochanteric fractures prevailed. In women and men with a limited mobility, fractures were sustained at the highest mean age (85 years in women, 84 years in men) compared to the other levels of mobility. In mobile patients, a significant difference (p < 0.001) was found between the age of women and men at which the fracture was sustained (79 years vs. 71 years). The largest significant difference (p < 0.001) in the age of fracture is seen in night time (84 years in women, 71 years in men). The highest number of injuries was suffered in the months of October to January, whereas the lowest number was reported in the period from June to July. DISCUSSION The epidemiological studies underline a notably higher incidence of proximal femoral fractures in women than in men, which was also confirmed by our study. The mean age of women with proximal femoral fracture was significantly higher compared to men. Similar conclusions have been drawn also by other studies. The incidence of fractures in dependence on the age group was the highest in women and men in their 9th decade, which compared to the previous studies was at a later age. This finding can be justified by aging of the Czech population, with the growing number of persons in the 9 th decade age group between 2012 and 2017 by 40,000. Nonetheless, men prevailed in fractures until the 9 th decade, while from the 9 th decade there is a marked growth in the number of these fractures sustained by women. This corresponds with the findings of other authors. As to the individual types of fractures (neck, trochanteric fracture) no difference was revealed in the percentage of women and men. In both genders intracapsular and petrochanteric fractures prevailed. Neither the level of pre-fracture mobility, nor the time of injury have been sufficiently monitored and evaluated with regard to the age of patients, therefore there is no adequate data to compare our results with. The lowest mean age at the time of injury was achieved by fully mobile men (71 years), which can be attributable to their sports and social activities performed at this age. The highest number of proximal femoral fractures was reported in the period from October to January, whereas their lowest number was reported in the period from June to July, which corresponds with the majority of other conducted studies in this area of research. CONCLUSIONS A considerably higher incidence of proximal femoral fractures in women was confirmed. The mean age of women with proximal femoral fracture was significantly higher than in men (82 vs. 77 years). Men prevailed in the number of fractures up to the 9 th decade, whereas from the 9 th decade the number of proximal femoral fractures in women significantly grew. In individual types of fractures (neck, trochanteric fractures), no difference in percentage of women and men was found. In both the genders intracapsular and pertrochanteric fractures significantly prevailed. The lowest mean age (71 years) at the time of injury was achieved by fully mobile men. The same age was identified in men also with respect to injuries sustained at night. The highest number of proximal femoral fractures was reported in the period from October to January, the lowest in the period from June to July. The knowledge of these seasonal variations can help plan the health care in the medical facility concerned. Key words: proximal femur, fracture, gender, mobility, day-time, seasonality.
- MeSH
- dospělí MeSH
- fraktury femuru * epidemiologie chirurgie MeSH
- fraktury krčku femuru * epidemiologie chirurgie MeSH
- fraktury kyčle * epidemiologie chirurgie MeSH
- incidence MeSH
- lidé středního věku MeSH
- lidé MeSH
- omezení pohyblivosti MeSH
- rizikové faktory MeSH
- roční období MeSH
- senioři MeSH
- sexuální faktory MeSH
- věkové faktory MeSH
- vnitřní fixace fraktury * metody statistika a číselné údaje MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
Coupling of ion mobility with mass spectrometry has brought new frontiers in separation and quantitation of a wide range of isobaric/isomeric compounds. Ion mobility spectrometry may separate ions possessing the identical molecular formula but having different molecular shapes. The separation space in most commercially available instruments is limited and rarely the mobility resolving power exceeds one hundred. From this perspective, new approaches allowing for extracting individual compound signals out of a more complex mixture are needed. In this work we present a new simple analytical approach based on fitting of arrival time distribution (ATD) profiles by Gaussian functions and generating of ATD functions. These ATD functions well describe even distorted ion mobility peaks of individual compounds and allow for extracting their peaks from mobilograms of mixtures. Contrary to classical integration, our approach works well with irregular overlapping peaks. Using mobilograms of standards to generate ATD functions, poorly separated compounds, e.g. isomers, with identical mass spectra representing a hard to solve task for various chemometric methods can be easily distinguished by our procedure. Alternatively ATD functions can be obtained from ATD profiles of ions unique to individual mixture components (if such ions exist) and mobilograms of standards are not required. On a set of hyaluronan-derived oligosaccharides we demonstrated excellent ATD repeatability enabling the resolution of binary mixtures, including mixtures with minor component level about 5%. Ion mobility quantitative data of isomers were confirmed by high performance liquid chromatography.
- Klíčová slova
- Analysis of isomers, Fitting of mobility peaks, Hyaluronan-derived oligosaccharides, Ion mobility-mass spectrometry,
- Publikační typ
- časopisecké články MeSH
The aim of this review is to evaluate the health and social effects of accessible home environments for people with functional limitations, in order to provide evidence to promote well-informed decision making for policy guideline development and choices about public health interventions. MEDLINE and nine other electronic databases were searched between December 2014 and January 2015, for articles published since 2004. All study types were included in this review. Two reviewers independently screened 12,544 record titles or titles and abstracts based on our pre-defined eligibility criteria. We identified 94 articles as potentially eligible; and assessed their full text. Included studies were critically appraised using the Mixed Method Appraisal Tool, version 2011. Fourteen studies were included in the review. We did not identify any meta-analysis or systematic review directly relevant to the question for this systematic review. A narrative approach was used to synthesise the findings of the included studies due to methodological and statistical heterogeneity. Results suggest that certain interventions to enhance the accessibility of homes can have positive health and social effects. Home environments that lack accessibility modifications appropriate to the needs of their users are likely to result in people with physical impairments becoming disabled at home.
- Klíčová slova
- International Classification of Functioning, activities of daily living, architectural accessibility, disability and health,
- MeSH
- architektonická přístupnost * MeSH
- bydlení * MeSH
- lidé MeSH
- omezení pohyblivosti * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- systematický přehled MeSH
The aim of this study was to evaluate the mobility of copper (Cu) and zinc (Zn) and their impact on the properties of bentonites and unfrozen water content. Limited research in this area necessitates further analysis to prevent the negative effects of metal interactions on bentonite effectiveness. Tests involved American (SWy-3, Stx-1b) and Slovak (BSvk) bentonite samples with Zn or Cu ion exchange. Sequential extraction was performed using the Community Bureau of Reference (BCR) method. Elemental content was analyzed via inductively coupled plasma optical emission spectrometry (ICP-OES). Unfrozen water content was measured using nuclear magnetic resonance (1H-NMR) and differential scanning calorimetry (DSC). Results showed a significant influence of the main cation (Zn or Cu) on ion mobility, with toxic metal concentrations increasing mobility and decreasing residual fractions. Mobile Zn fractions increased with larger particle diameters, lower clay content, and shorter interplanar spacing, while the opposite was observed for Cu. Zn likely accumulated in larger clay pores, while Cu was immobilized in the bentonite complex. The stability of Zn or Cu ions increased with higher clay content or specific surface area. Residual Zn or Cu fractions were highest in uncontaminated bentonites with higher unfrozen water content, suggesting the potential formation of concentrated solutions in sub-zero temperatures, posing a threat to the clay-water environment, especially in cold regions.
- Klíčová slova
- bentonite, environmental protection, mobility of toxic metals, physicochemical characterization of porous adsorbents, unfrozen water content,
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: This study aimed to compare the immediate influence of four commonly used retainer wires on tooth mobility following orthodontic treatment with fixed appliances. MATERIALS AND METHODS: Eighty patients after orthodontic treatment were assigned to four study groups (n = 20 in each group). Groups were provided with directly bonded fixed retainers-0.0150″ (group A), 0.0175″ (group B), 0.016 × 0.022″ (group C), and 0.0215″ (group D). Tooth mobility was measured using the Periotest device at two times-after removal of fixed appliance (T1) and after bonding of the retainer (T2). Values of tooth mobility, 'Periotest values', were analysed between groups and compared with the physiologic tooth mobility in a control group of untreated patients (n = 65). Kruskal-Wallis H, Mann-Whitney U, Dunn's test, Fisher's exact test, and binary logistic regression tests were used to analyze the data. RESULTS: Tooth mobility after orthodontic treatment was significantly increased. While canines remained within normal range of tooth mobility, values for incisors increased on average to the first degree of tooth mobility (slight mobility). Logistic regression analysis identified age as a significant predictor for increased tooth mobility (P = 0.032) with odds ratio 1.065 (95% CI 1.005-1.128), with mobility increasing with age. After bonding of the retainer in all four groups, the tooth mobility was reduced to values which were not significantly different form normal physiological values found in the control group (P > 0.05). There were no differences in the amount of change or in tooth mobility values at T2 between the different types of bonded retainers. LIMITATIONS: Age of subjects in the control group was significantly higher than that in the study groups. An alternation method was used instead of randomization to distribute the four different types of retainers. CONCLUSIONS: All of the retainer wires were able to successfully reduce the increased tooth mobility caused by orthodontic treatment to normal levels. The values of tooth mobility after placement of retainers were within the range of physiologic tooth mobility.