144 results on '"Barta K"'
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2. Synthesis of Enantioenriched Amines by Iron‐Catalysed Amination of Alcohols Employing at Least One Achiral Substrate
- Author
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Bottari, G., primary, Afanasenko, A., additional, Castillo‐Garcia, A. A., additional, Feringa, B. L., additional, and Barta, K., additional
- Published
- 2021
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3. A hirtelen szívhalál molekuláris és genetikai háttere
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Simkó, J., Szabó, Z., Barta, K., Újvárosi, D., Nánási, P., and Lőrincz, I.
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Orvostudományok ,Klinikai orvostudományok - Published
- 2012
4. A pitvarfibrilláció és a vegetatív idegrendszer
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Lőrincz, I., Szabó, Z., Simkó, J., Szánthó, E., Barta, K., Füzi, M., and Szigeti G
- Published
- 2008
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5. A syncope kivizsgálása és kezelése
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Lőrincz, I., Barta, K., and Szabó Z
- Published
- 2007
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6. The Impact of Soil Erosion on the Spatial Distribution of Soil Characteristics and Potentially Toxic Element Contents in a Sloping Vineyard in Tállya, Ne Hungary
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Manaljav Samdandorj, Farsang Andrea, Barta Károly, Tobak Zalán, Juhász Szabolcs, Balling Péter, and Babcsányi Izabella
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ptes ,soil organic matter ,soil erosion ,tokaj ,geostatistics ,interpolation ,Environmental sciences ,GE1-350 - Abstract
Soil erosion is a main problem in sloping vineyards, which can dramatically affect soil quality and fertility. The present study aimed to evaluate the spatial patterns of selected physico-chemical soil characteristics and the soil’s potentially toxic element (PTE) contents in the context of erosion. The study was conducted in a 0.4 ha vineyard plot on a steep slope in Tállya, part of the wine-growing region of Tokaj-Hegyalja (Hungary). A total of 20 topsoil samples (0-10 cm) were collected and analysed for PTEs (B, Co, Ba, Sr, Mn, Ni, Cr, Pb, Zn, and Cu), soil pH (deionized water and KCl solution), particle-size distribution, soil organic matter (SOM), (nitrate+nitrite)-N, P2O5, and carbonate content. Among the selected PTEs, only Cu (125±27 mg/kg) exceeds the Hungarian standards set for soils and sediments (75 mg/kg) due to the long-term use of Cu-based pesticides in the vineyard. Examined PTEs are negatively correlated with the sand content of the topsoil, except for Mn, while the significant positive relationship with the clay content shows the role of clay in retaining PTEs in soil. SOM seems to play a minor role in binding PTEs, as Cu is the only element for which a significant correlation with the SOM content can be detected. The spatial distribution maps prepared by inverse distance weighting (IDW) and lognormal kriging (LK) methods show higher PTE contents at the summit and the shoulder of the hillslope and lower contents at the backslope and the footslope zones. The low slope gradients (0-5 degree) and the high contents of the coarse fraction (> 35%) likely protect the soil at the summit and the hillslope’s shoulder from excessive erosion-induced losses. While the reraising PTE contents at the toeslope are likely due to the deposition of fine soil particles (silt and clay). The highest SOM contents at the summit and the toeslope areas, and increased contents of the coarse fraction at the backslope, confirm the effects of soil erosion on the spatial distribution patterns of main soil quality indicators. Overall, the LK outperformed the IDW method in predicting the soil parameters in unsampled areas.
- Published
- 2021
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7. Changes of cerebral blood flow during tilt table test in patients with vasovagal syncope
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Lőrincz I, Oláh L, Varga E, Barta K, Szabó Z, and Csiba L
- Published
- 2003
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8. Impact of Low-Dose Municipal Sewage Sludge Compost Treatments on the Nutrient and the Heavy Metal Contents in a Chernozem Topsoil Near Újkígyós, Hungary: A 5-Year Comparison
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Ladányi Zsuzsanna, Csányi Katalin, Farsang Andrea, Perei Katalin, Bodor Attila, Kézér Adrienn, Barta Károly, and Babcsányi Izabella
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sewage compost ,treatment ,heavy metal ,nutrient content ,agricultural application ,Environmental sciences ,GE1-350 - Abstract
Agriculture is one of the major fields, where sewage sludge can be used. Its high nutrient content can contribute to the improvement of important soil properties, such as nutrient content, water balance and soil structure. However, sewage sludge may contain hazardous components, such as pathogens and pollutants. Therefore, it is important to monitor the effects of its field application. In this paper, we assessed the impacts of two low-dose (2.5 m3/ha) municipal sewage sludge compost applications (in 2013 and in 2017) in a 5.6 ha arable land in southeast Hungary (near Újkígyós), located in the Hungarian Great Plain. The nutrient and the heavy metal contents in the upper soil layer (0-30 cm) of the studied Chernozem soils were compared between two sampling campaigns in 2013 (before the compost applications) and in 2018 (after the compost applications). Basic soil properties (pH, salinity, humus content, carbonate content, Arany yarn number) complemented with nutrient content (K2O, P2O5, NO2+ NO3) and heavy metal content (Cd, Co, Cr, Cu, Ni, Pb and Zn) analyses were performed. The results show that no significant change can be noticed in the baseline parameters over the 5-year period. The slight increase in the P2O5, NO2+ NO3 content is closely related to the beneficial effects of the sewage sludge deposition. The soil-bound heavy metal load did not increase significantly as a result of the compost treatments, only nickel showed a slight increase in the topsoil. In all cases the heavy metal concentrations did not reach the contamination thresholds set by Hungarian standards. The results provided positive evidences proving that low dose municipal sewage sludge compost disposal on agricultural land is safe, and can be considered as a sustainable soil amendment for agriculture in compliance with legal requirements.
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- 2020
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9. COMPLEMENT FIXATION TEST FOR PNEUMOCYSTOSIS
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BARTA, K.
- Published
- 1969
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10. 238 can echocardiographic early screening detect the doxorubicin induced cardiotoxicity?
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FULOP, T, primary, HEGEDUS, I, additional, EDES, I, additional, BARTA, K, additional, and LORINCZ, I, additional
- Published
- 2006
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11. A13-1 Changes of cerebral blood flow during tilt table test in patients with vasovagal syncope
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Lorincz, I., primary, Varga, E., additional, Barta, K., additional, Szabo, Z., additional, Olah, L., additional, and Csiba, L., additional
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- 2003
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12. Integrating Time and Resources into Planning.
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Dvor?a?k, F. and Barta?k, R.
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- 2010
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13. Immunologische Eigenschaften der menschlichen mit Heparin präzipitierten Plasmafraktion
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Barta, K. and Bartova, A.
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- 1960
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14. School nurse summer institute: model for professional development.
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Neighbors M and Barta K
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The components of a professional development model designed to empower school nurses to become leaders in school health services is described. The model was implemented during a 3-day professional development institute that included clinical and leadership components, especially coalition building, with two follow-up sessions in the fall and spring. Coalition building is an important tool to enhance the influence of the school nurse in improving the health of individuals, families, and communities. School nurses and nursing educators with expertise in the specialty of school nursing could replicate this model in their own regions. [ABSTRACT FROM AUTHOR]
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- 2004
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15. Mapping Freshwater Carbonate Deposits by Using Ground-Penetrating Radar at Lake Kolon, Hungary
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Pécsi Eszter, Katona Orsolya, Barta Károly, Sipos György, and Biró Csaba
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freshwater limestone ,ground-penetrating radar ,lake kolon ,drilling ,Environmental sciences ,GE1-350 - Abstract
Freshwater carbonate deposit, as a special phenomenon in the Danube-Tisza Interfluve, located in the centre of Hungary, is a significant geological heritage in the Carpathian Basin. At present there is not any applicable method to investigate the presence of carbonate layers in an undisturbed way, as neither vegetation nor morphological characteristics indicate unambiguously these formations. Ground-penetrating radar technology is widely used in various earth science related researches, and the number of applications is steadily increasing. The aim of the study was to determine the spatial extension of freshwater limestone using geophysical methods near Lake Kolon, Hungary. The lake, which is now a protected wetland area with opened water surfaces, was formed in the paleo-channel of the River Danube. Measurements were performed with the help of ground-penetrating radar, the results were calibrated by high spatial resolution drillings. Investigations have been made since 2012, and freshwater limestone was detected at several locations determining the more exact extension of the formation. Ground-penetrating radar proved to be an appropriate method to detect the compact and fragmented freshwater limestone layers in such an environment. However, based on the results the method can be best applied under dry soil or sediment conditions while the uncertainty of the results increases significantly as a matter of higher soil moisture. Further control measurements are necessary verified by several drillings in order to give an exact method to determine freshwater limestone.
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- 2014
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16. Role of Genetic Recombination in DNA Replication of Bacteriophage Lambda I. Genetic Characterization of the Delta Gene
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Barta, K., Tavernier, P., and Zissler, J.
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We describe the isolation and genetic characterization of point mutations in gene delta, including a temperature-sensitive mutation (del206). Genetic methods enable the extraction of a delta mutation from the triple mutant (del,red,gam) and the construction of new genotypes, including del,redand del,gamdouble mutants. Tests of plating efficiency indicate gene delta is essential for normal phase growth on the polAhost. The possible association of delta in a system involving alpha, beta, and gamma is considered.
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- 1974
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17. Role of Genetic Recombination in DNA Replication of Bacteriophage Lambda II. Effect in DNA Replication by Gene Delta
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Barta, K. and Zissler, J.
- Abstract
We have studied the effect of delta mutations in phage lambda on DNA synthesis as assayed by the accumulation of ? DNA in infected cells. We find that delta mutants appear to generate somewhat less DNA than ?+in a rec+host, suggesting the wild-type delta gene may act in DNA replication. An additional clue to delta function arises if replication is measured in the gamma-negative situation where concatemer formation is abortive. In this situation, the wild-type delta gene has an “inhibitory” effect on replication. A similar inhibitory effect on replication due to delta is observed after infection of P2lysogens. We conclude from these studies that the delta gene may act with alpha, beta, and gamma genes, possibly in a process affecting DNA replication.
- Published
- 1974
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18. Estimation of Soil Material Transportation by Wind Based on in Situ Wind Tunnel Experiments
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Farsang Andrea, Duttmann Rainer, Bartus Máté, Szatmári József, Barta Károly, and Bozsó Gábor
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deflation ,wind tunnel experiment ,nutrient transport ,Environmental sciences ,GE1-350 - Abstract
25% and 40% of territory of Hungary is moderate to highly vulnerable to deflation. However, precise estimates about the soil loss and related losses of organic matter and nutrients due to wind erosion are missing in most cases. In order to determine magnitudes of nutrient masses removed at wind velocities that frequently occur in SE Hungary, in-situ experiments using a portable wind tunnel have been conducted on small test plots with an erosional length of 5.6 m and a width of 0.65 m. The wind tunnel experiments have been carried through on a Chernozem which is typical for this region. In order to compare the effects of soil coverage on the masses of blown soil sediment and adsorbed nutrients, two soil surface types have been tested under similar soil moisture und atmospheric conditions: (1) bare soil (dead fallow) and (2) bare soil surface interrupted by a row of maize plants directed downwind along the center line of the test plots. The results of our experiments clearly show that a constant wind velocity of 15 m s-1 (at a height of 0.3 m) lasting over a short time period of 10 minutes can already cause noticeable changes in the composition and size of soil aggregates at the top of the soil surface. Due to the grain size selectivity of the erosive forces the relative share of soil aggregates comprising diameters > 1 mm increased by 5-10% compared with the unaffected soil. Moreover it has shown that short time wind erosion events as simulated in this study can result in erosion rates between 100 and 120 g m-2, where the erosion rates measured for bare soils are only slightly, but not significantly higher than those of the loosely vegetated ones. Soil samples taken from sediment traps mounted in different heights close to the outlet of the wind tunnel point to an enrichment of organic matter (OM) of about 0.6 to 1 % by mass referred to the control samples. From these findings has been calculated that the relocation of organic matter within short term wind erosion events can amount to 4.5 to 5.0 g OM m-2. With the help of portable field wind tunnel experiments we can conclude that our valuable, high quality chernozems are struck by wind erosion mainly in drought periods.
- Published
- 2013
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19. Inland Excess Water Projection Based on Meteorological and Pedological Monitoring Data on a Study Area Located in the Southern Part of the Great Hungarian Plain
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Barta Károly
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excess water ,infiltration ,water budget ,soil ,Environmental sciences ,GE1-350 - Abstract
The research investigated the process of excess water formation. Complex measurement stations were developed in order to determine the most important hydro-meteorological and soil factors contributing to the formation of excess water. The stations measure the amount of precipitation, evapotranspiration, evaporation from water surface, soil moisture in 3 different depths; soil temperature in 5 different depths; furthermore, soil water level. The study area is located in the southeastern part of Hungary, near Szeged, in the flood plain of Tisza and Maros with extremely clayey soils. The former soil data were completed by new soil survey to determine several soil parameters (e.g. bulk density, porosity, field capacity, saturated hydraulic conductivity). Infiltration was calculated from the measured parameters and water budget elements of bigger rainfall event were analyzed between March 2010 and August 2011. Genetic types of excess water can be separated based on the data.
- Published
- 2013
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20. Comparison of Pipette and Laser Diffraction Methods in Determining the Granulometric Content of Fluvial Sediment Samples
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Kun Ágnes, Katona Orsolya, Sipos György, and Barta Károly
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laser diffraction method ,pipette method ,fluvial sediments ,grain size distribution ,Environmental sciences ,GE1-350 - Abstract
Nowadays there is a growing demand for rapid and accurate determination of grain size distribution. The conventional pipette method is time-consuming and provides less detailed data compared to recently introduced methods. However, in Hungarian practice the pipette method is still considered to be the standard one, as there are a long series of measurements, and grain size thresholds used in sedimentology and soil sciences are based on this approach. The aim of our research was to determine the comparability of the laser diffraction method (LDM) with the conventional pipette method (PM), in order to investigate the controversial question on the interchangeability of the two methods. Based on our measurements on some representative fluvial sediment samples, we found that the largest difference in results can be expected in the silty grain size range. However if the main fractions (clay, silt, sand) are considered the methods provided similar very results, and correlation factors were above 0.92. In all, the LDM has a clear advantage because of its speed, reproducibility and fewer possibilities for operator failure.
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- 2013
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21. ChemInform Abstract: THE REACTION OF O-TETRAACETYLGLUCOSYLUREA WITH FORMALDEHYDE
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GERECS, A., primary, BARTA, K., additional, HEMELA, J., additional, and ROCKENBAUER, A., additional
- Published
- 1975
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22. Effects of Manual Therapy and Dry Needling Techniques for Managing Hypertonicity in the Male Pelvic Floor: A Case Report.
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Porter, A., Trotter, S. F., and Barta, K.
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MUSCLE rigidity ,MANIPULATION therapy ,MUSCLES ,MYOFASCIAL pain syndrome treatment ,PELVIC floor ,THERAPEUTICS - Published
- 2017
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23. A13-1 Changes of cerebral blood flow during tilt table test in patients with vasovagal syncope.
- Author
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Lorincz, I., Varga, E., Barta, K., Szabo, Z., Olah, L., and Csiba, L.
- Published
- 2002
24. Acidic organophosphorus extractants—VI: Extraction of calcium and strontium by dioctyl phosphoric acids in various diluents
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Šístková, N.V., Kolařík, Z., Bárta, K., and Pánková, H.
- Published
- 1968
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25. PRECIPITATION AND COPRECIPITATION IN THE PRESENCE OF CHELATING AGENTS. V. THE CONTAMINATION OF BARIUM CHROMATE BY URANIUM FISSION PRODUCTS IN EDTA.
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Barta, K
- Published
- 1969
26. Transcutaneous Spinal Stimulation Combined with Locomotor Training Improves Functional Outcomes in a Child with Cerebral Palsy: A Case Study.
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Atkinson D, Barta K, Bizama F, Anderson H, Brose S, and Sayenko DG
- Abstract
Background and Purpose: activities-based locomotor training (AB-LT) is a restorative therapeutic approach to the treatment of movement deficits in people with non-progressive neurological conditions, including cerebral palsy (CP). Transcutaneous spinal stimulation (TSS) is an emerging tool in the rehabilitation of individuals with sensorimotor deficits caused by neurological dysfunction. This non-invasive technique delivers electrical stimulation over the spinal cord, leading to the modulation of spinal sensorimotor networks. TSS has been used in combination with AB-LT and has been shown to improve muscle activation patterns and enhance motor recovery. However, there are no published studies comparing AB-LT + TSS to AB-LT alone in children with CP. The purpose of this case study was to compare the impact of AB-LT alone versus AB-LT combined with TSS on functional movement and quality of life in a child with CP., Methods: A 13-year-old male with quadriplegic CP participated in this pilot study. He was classified in the Gross Motor Function Classification System (GMFCS) at Level III. He completed 20 sessions of AB-LT (5x/week), then a 2-week washout period, followed by 20 sessions of body-AB-LT + TSS. Treatment sessions consisted of 1 h of locomotor training with body weight support and manual facilitation and 30 min of overground play-based activities. TSS was applied using the RTI Xcite
® , with stimulation at the T11 and L1 vertebral levels. Assessments including the Gross Motor Function Measure (GMFM), 10-m walk test (10 MWT), and Pediatric Balance Scale (PBS) were performed, while spatiotemporal gait parameters were assessed using the Zeno Walkway® . All assessments were performed at three time points: before and after AB-LT, as well as after AB-LT + TSS., Outcomes: After 19/20 sessions of AB-LT alone, the participant showed modest improvements in the GMFM scores (from 86.32 to 88), 10 MWT speed (from 1.05 m/s to 1.1 m/s), and PBS scores (from 40 to 42). Following the AB-LT combined with TSS, scores improved to an even greater extent compared with AB-LT alone, with the GMFM increasing to 93.7, 10 MWT speed to 1.43 m/s, and PBS to 44. The most significant gains were observed in the GMFM and 10 MWT. Additionally, improvements were noted across all spatiotemporal gait parameters, particularly at faster walking speeds. Perhaps most notably, the child transitioned from the GMFCS level III to level II by the end of the study., Discussion: Higher frequency and intensity interventions aimed at promoting neuroplasticity to improve movement quality in children with CP are emerging as a promising alternative to traditional physical therapy approaches. This case study highlights the potential of TSS to augment neuroplasticity-driven treatment approaches, leading to improvements in neuromotor function in children with CP. These findings suggest that TSS could be a valuable addition to rehabilitation strategies, warranting further research to explore its efficacy in larger populations.- Published
- 2024
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27. Progressive muscle relaxation, meditation, and mental practice-based interventions for the treatment of tremor after traumatic brain injury.
- Author
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Campbell AH, Barta K, Sawtelle M, and Walters A
- Subjects
- Humans, Male, Middle Aged, Activities of Daily Living, Treatment Outcome, Electromyography, Tremor therapy, Tremor etiology, Meditation, Brain Injuries, Traumatic complications, Brain Injuries, Traumatic therapy, Quality of Life
- Abstract
Background and Purpose: Individuals post traumatic brain injury (TBI) are likely to experience cognitive, sensory, and motor impairments. Tremor is a common movement disorder that can affect this patient population. The purpose of this case report was to describe the effects that progressive muscle relaxation, meditation, and mental practice-based interventions have on the treatment of chronic right upper extremity tremor in a patient post-TBI., Case Description: A 47-year-old male with a traumatic brain injury presented with a resting and postural tremor of the right wrist flexors and deficits in cognition, sensation, proprioception, balance, and motor function. The patient's primary goal for therapy was to decrease the tremor to improve his quality of life and ability to perform activities of daily living., Methods: Progressive muscle relaxation, breath-focused meditation, and mental practice-based intervention were administered to the patient. Active range of motion activities occurred during weekly in-person sessions and daily practice occurred at home., Results: The patient demonstrated improvements in quality of life, self-ratings of tremor severity, ratings of tremor impact on ADL's, gross motor object manipulation, frequency of tremor via surface electromyography, and visual inspection of a spirograph., Conclusion: A combination of progressive muscle relaxation, meditation, and mental practice-based interventions appeared to positively impact tremor across physical and psychosocial domains in a patient with a chronic tremor. Further investigation is needed to verify these findings.
- Published
- 2024
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28. A Critical Review of Breastfeeding Instruments Derived From Self-Determination Theory.
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Barta K
- Subjects
- Humans, Female, Surveys and Questionnaires, Breast Feeding psychology, Personal Autonomy, Motivation
- Abstract
Background: Understanding the motivational factors that influence breastfeeding behavior is critical for addressing suboptimal breastfeeding outcomes. Self-determination theory has been used as a framework to understand these factors., Research Aim: The aim of this article is to identify and critically review breastfeeding instruments derived from self-determination theory and their subsequent uses in the literature., Method: This critical review was guided by Grant and Booth's typological description. Eligibility criteria included full-text, peer-reviewed original instrument development and validation articles, written in the English language without limitation to specific years. Articles describing the use of the eligible instruments were also included. There were 164 articles identified initially, and four instruments were included in the final sample. Finally, five articles, including subsequent uses of the instruments were critically analyzed and an overview, assessment of validation, and analysis of subsequent use of each instrument is presented., Results: All instruments examine the degree of autonomy underlying breastfeeding motivation. The extent and quality of validation varied. Two instruments have been used in subsequent studies; one was adapted and translated into Turkish and used in three other studies, and another was used in full in one subsequent use and in part in another study. Three of four were initially developed for prenatal administration., Conclusions: Instruments derived from self-determination theory hold promise in exploring the autonomy underlying breastfeeding motivations. Researchers who wish to use or adapt these instruments should consider the instruments' domains, validity, and administration. New measures are needed to explore other constructs from self-determination theory related to breastfeeding., Competing Interests: Disclosures and Conflicts of InterestThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2024
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29. Psychometric properties of 3-meter backward walk test (3MBWT) in people with Parkinson disease.
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Barta K, Boddy AH, Flores M, Perry L, Sawyer K, and Campbell A
- Abstract
Background and Purpose: The purpose of this study was to investigate the 3-meter backward walk test (3MBWT) in individuals with Parkinson Disease (PD) to determine the following: (1) concurrent validity with other gait velocity measures and (2) interrater and intrarater reliability of in-person and video assessment., Methods: A convenience sample of 25 people with PD participated. Forward gait velocity was measured using a computerized walkway (Zeno Walkway System), the 10-meter walk test (10MWT), and 4-meter walk test (4MWT). Backward gait velocity was measured using the 3MBWT. Concurrent validity was assessed using Pearson's correlations. Reliability was assessed using intra-class correlation coefficients (ICC
(2,1) )., Results: All relationships between the 3MBWT and gait outcome measures were significant. The 3MBWT demonstrated strong correlations with the 4MWT dual task ( r = .795, p =<.001) and moderate correlations with 4MWT comfortable walking speed ( r = .658, p < .001), 4MWT fast walking speed ( r = .601, p =.002), 10MWT comfortable walking speed ( r = .512, p = .009), and 10MWT dual task ( r = .535, p = .006). A low yet significant correlation was noted with the 10MWT fast walking speed ( r = .398, p = .049). Association between the 3MBWT and the Zeno Walkway System revealed moderate correlations. All reliability tests were significant at p < .001. Interrater reliability ICC(2,1) values were very high for 3MBWT (ICC(2,1) = 0.93, [0.83-0.91]). Intrarater reliability was also very high (ICC(2,1) = 0.96 [0.90-0.98])., Conclusion: The 3MBWT demonstrates validity and reliability as a tool for assessing gait speed in the posterior direction in people with PD.- Published
- 2024
- Full Text
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30. Topical Steroid Withdrawal is a Targetable Excess of Mitochondrial NAD.
- Author
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Shobnam N, Saksena S, Ratley G, Yadav M, Chaudhary PP, Sun AA, Howe KN, Gadkari M, Franco LM, Ganesan S, McCann KJ, Hsu AP, Kanakabandi K, Ricklefs S, Lack J, Yu W, Similuk M, Walkiewicz MA, Gardner DD, Barta K, Tullos K, and Myles IA
- Abstract
Background: Topical corticosteroids (TCS) are first-line therapies for numerous skin conditions. Topical Steroid Withdrawal (TSW) is a controversial diagnosis advocated by patients with prolonged TCS exposure who report severe systemic reactions upon treatment cessation. However, to date there have been no systematic clinical or mechanistic studies to distinguish TSW from other eczematous disorders., Methods: A re-analysis of a previous survey with eczematous skin disease was performed to evaluate potential TSW distinguishing symptoms. We subsequently conducted a pilot study of 16 patients fitting the proposed diagnostic criteria. We then performed: tissue metabolomics, transcriptomics, and immunostaining on skin biopsies; serum metabolomics and cytokine assessments; shotgun metagenomics on microbiome skin swabs; genome sequencing; followed by functional, mechanistic studies using human skin cell lines and mice., Results: Clinically distinct TSW symptoms included burning, flushing, and thermodysregulation. Metabolomics and transcriptomics both implicated elevated NAD+ oxidation stemming from increased expression of mitochondrial complex I and conversion of tryptophan into kynurenine metabolites. These abnormalities were induced by glucocorticoid exposure both in vitro and in a cohort of healthy controls (N=19) exposed to TCS. Targeting complex I via either metformin or the herbal compound berberine improved outcomes in both cell culture and in an open-label case series for patients with TSW., Conclusion: Taken together, our results suggest that TSW has a distinct dermatopathology. While future studies are needed to validate these results in larger cohorts, this work provides the first mechanistic evaluation into TSW pathology, and offers insights into clinical identification, pharmacogenomic candidates, and directed therapeutic strategies.
- Published
- 2024
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31. Closed-loop recyclability of a biomass-derived epoxy-amine thermoset by methanolysis.
- Author
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Wu X, Hartmann P, Berne D, De Bruyn M, Cuminet F, Wang Z, Zechner JM, Boese AD, Placet V, Caillol S, and Barta K
- Abstract
Epoxy resin thermosets (ERTs) are an important class of polymeric materials. However, owing to their highly cross-linked nature, they suffer from poor recyclability, which contributes to an unacceptable level of environmental pollution. There is a clear need for the design of inherently recyclable ERTs that are based on renewable resources. We present the synthesis and closed-loop recycling of a fully lignocellulose-derivable epoxy resin (DGF/MBCA), prepared from dimethyl ester of 2,5-furandicarboxylic acid (DMFD), 4,4'-methylenebis(cyclohexylamine) (MBCA), and glycidol, which displays excellent thermomechanical properties (a glass transition temperature of 170°C, and a storage modulus at 25°C of 1.2 gigapascals). Notably, the material undergoes methanolysis in the absence of any catalyst, regenerating 90% of the original DMFD. The diamine MBCA and glycidol can subsequently be reformed by acetolysis. Application and recycling of DGF/MBCA in glass and plant fiber composites are demonstrated.
- Published
- 2024
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32. Aniline Derivatives from Lignin under Mild Conditions Enabled by Electrochemistry.
- Author
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Castillo-Garcia AA, Kappe CO, Cantillo D, and Barta K
- Abstract
The development of environmentally friendly methods for the valorization of important phenolic platform chemicals originating directly from lignin-first depolymerization into value-added N-chemicals, such as aniline derivatives, is of high industrial interest. In this work, we tackle this challenging transformation by the judicious combination of electrochemical conversion and chemical functionalization steps. In the first step, lignin-derived para-substituted guaiacols and syringols undergo an atom-efficient, room-temperature anodic oxidation using methanol both as solvent and reagent towards the formation of the corresponding cyclohexadienone derivatives, which are subsequently converted to synthetically challenging ortho-methoxy substituted anilines by reaction with ethyl glycinate hydrochloride under mild conditions. The developed method was applied to crude lignin depolymerization bio-oils, derived from reductive catalytic fractionation (RCF) mediated either by copper-doped porous metal oxide (Cu
20 PMO) or Ru/C, allowing the selective production of 4-propanol-2-methoxyaniline (1Gb) and 4-propyl-2-methoxyaniline (2Gb), respectively, from pine lignocellulose. Finally, the application of 2Gb was further studied in the synthesis of carbazole 2Gc, a lignin-derived analogue of biologically active alkaloid murrayafoline A., (© 2023 The Authors. ChemSusChem published by Wiley-VCH GmbH.)- Published
- 2024
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33. Clean Synthetic Strategies to Biologically Active Molecules from Lignin: A Green Path to Drug Discovery.
- Author
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Afanasenko AM, Wu X, De Santi A, Elgaher WAM, Kany AM, Shafiei R, Schulze MS, Schulz TF, Haupenthal J, Hirsch AKH, and Barta K
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- Solvents chemistry, Catalysis, Biomass, Lignin chemistry, Drug Discovery
- Abstract
Deriving active pharmaceutical agents from renewable resources is crucial to increasing the economic feasibility of modern biorefineries and promises to alleviate critical supply-chain dependencies in pharma manufacturing. Our multidisciplinary approach combines research in lignin-first biorefining, sustainable catalysis, and alternative solvents with bioactivity screening, an in vivo efficacy study, and a structural-similarity search. The resulting sustainable path to novel anti-infective, anti-inflammatory, and anticancer molecules enabled the rapid identification of frontrunners for key therapeutic indications, including an anti-infective against the priority pathogen Streptococcus pneumoniae with efficacy in vivo and promising plasma and metabolic stability. Our catalytic methods provided straightforward access, inspired by the innate structural features of lignin, to synthetically challenging biologically active molecules with the core structure of dopamine, namely, tetrahydroisoquinolines, quinazolinones, 3-arylindoles and the natural product tetrahydropapaveroline. Our diverse array of atom-economic transformations produces only harmless side products and uses benign reaction media, such as tunable deep eutectic solvents for modulating reactivity in challenging cyclization steps., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
- Published
- 2024
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34. Topographic depressions can provide climate and resource microrefugia for biodiversity.
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Frei K, Vojtkó A, Farkas T, Erdős L, Barta K, E-Vojtkó A, Tölgyesi C, and Bátori Z
- Abstract
Microrefugia are often located within topographically complex regions where stable environmental conditions prevail. Most of the studies concerning the distributions of climate change-sensitive species have emphasized the dominance of cold air pooling over other environmental factors, such as resource availability. There is a shortage of information on the relationships among topography-related microsite diversity, microclimate, resource availability, and species composition in microrefugia. To fill this knowledge gap, we studied the effects of microclimatic conditions and soil resources on plant species occurrence within and adjacent to 30 large topographic depressions (i.e., dolines) in two distant karst regions. Our results showed that both microclimate and soil resource availability may play a key role in maintaining climate change-sensitive species and biodiversity in dolines; therefore, they may simultaneously act as climate and resource microrefugia. Establishing climate-smart conservation priorities and strategies is required to maintain or increase the refugial capacity of such safe havens., Competing Interests: The authors declare that they have no competing interests., (© 2023 The Author(s).)
- Published
- 2023
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35. Deriving high value products from depolymerized lignin oil, aided by (bio)catalytic funneling strategies.
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Wu X, De Bruyn M, and Barta K
- Abstract
Lignin holds tremendous and versatile possibilities to produce value-added chemicals and high performing polymeric materials. Over the years, different cutting-edge lignin depolymerization methodologies have been developed, mainly focusing on achieving excellent yields of mono-phenolic products, some even approaching the theoretical maximum. However, due to lignin's inherent heterogeneity and recalcitrance, its depolymerization leads to relatively complex product streams, also containing dimers, and higher molecular weight fragments in substantial quantities. The subsequent chemo-catalytic valorization of these higher molecular weight streams, containing difficult-to-break, mainly C-C covalent bonds, is tremendously challenging, and has consequently received much less attention. In this minireview, we present an overview of recent advances on the development of sustainable biorefinery strategies aimed at the production of well-defined chemicals and polymeric materials, the prime focus being on depolymerized lignin oils, containing high molecular weight fractions. The key central unit operation to achieve this is (bio)catalytic funneling, which holds great potential to overcome separation and purification challenges.
- Published
- 2023
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36. Survey of topical exposure concerns for patients and caregivers dealing with atopic dermatitis.
- Author
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Ratley G, Sun AA, Capozza K, Barta K, and Myles IA
- Abstract
Background: Despite the recent expansion of treatment options in atopic dermatitis (AD), most management responsibilities fall on the patient and/or caregivers. Disease control often requires vigilance about and avoidance of common exposures, however the concerns for patients and caregivers living with AD have not been well enumerated., Methods: An IRB approved survey was distributed to the public to evaluate the patient and caregiver concerns for topical exposures and potential triggers., Results: 323 people accessed the link to the survey with 259 providing response to at least one section of questions (response rate 80.2%). Results indicated that temperature and other weather related changes were the most common trigger. Nearly all respondents avoided at least one topical ingredient, with fragrances being the most common. Steroid exposure was common, however respondents expressed concerns about overall steroid exposure., Conclusions: Our results attempt to enumerate the daily topical exposure concerns for patients and caregivers living with AD. While our online survey is both limited and without mechanistic insights, our results provide insight to providers by highlighting the role of temperature in AD symptoms; identifying commonly perceived triggers; indicating the value of provider insight for topical product selection; and indicating that no specific aspect of topical corticosteroid exposure may alleviate the general steroid concerns for patients or caregivers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Ratley, Sun, Capozza, Barta and Myles.)
- Published
- 2023
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37. Environmental heterogeneity increases the conservation value of small natural features in karst landscapes.
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Bátori Z, Valkó O, Vojtkó A, Tölgyesi C, Farkas T, Frei K, Hábenczyus AA, Tóth Á, Li G, Rádai Z, Dulai S, Barta K, Erdős L, and Deák B
- Subjects
- Soil, Climate Change, Conservation of Natural Resources methods, Ecosystem, Biodiversity
- Abstract
Local biodiversity hotspots are often located within regions where extreme and variable environmental - e.g., climatic and soil - conditions occur. These areas are conservation priorities. Although environmental heterogeneity is recognised as an important determinant of biodiversity, studies focusing on the effects of multiple environmental heterogeneity components in the same ecosystem are scarce. Here we investigate how topography and related microclimatic variables and soil properties may influence the biodiversity and conservation value of karst landscapes. Karst landscapes of the world contain millions of dolines (i.e. bowl- or funnel-shaped depressions) that may function as 'small natural features' with a disproportionately large role in maintaining biodiversity relative to their size. We assessed the diversity of microclimates, soils and vegetation and their relationships in six microhabitats (south-facing slopes, east-facing slopes, west-facing slopes, north-facing slopes and bottoms of dolines, and the adjacent plateau) for nine large dolines in a grassland ecosystem. Although there were remarkable differences among the conservation value of these microhabitats (e.g., representation of different species groups, presence of 'climate relicts'), each microhabitat had an important role in maintaining species that are rare or absent in other microhabitats in the landscape. We found that the studied dolines exhibited highly variable environmental conditions and promoted a high diversity of vegetation types with unique species composition, contributing to the topographic, climatic, soil, vegetation and land cover heterogeneity of karst landscapes. Therefore, our findings highlight that dolines may function as local biodiversity hotspots and have a crucial conservation importance. As dolines are widespread topographic features in many karst landscapes throughout the world, our results could be directly applied to other regions as well. An integrated approach is urgently needed to provide guidelines for landscape management, promoting the retention of the microhabitat diversity of small natural features for species vulnerable to climate change and/or various disturbances., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2023
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38. An Analysis of Telehealth in the Outpatient Management of Atrial Fibrillation During the COVID-19 Pandemic.
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Shatla I, El-Zein RS, Ubaid A, ElBallat A, Sammour Y, Kennedy KF, Barta K, Brand-Moody T, Cordle F, Williams L, Giocondo M, Gupta S, Ramza B, Steinhaus D, Yousuf O, Spertus JA, and Wimmer AP
- Subjects
- Humans, Outpatients, Pandemics, Atrial Fibrillation drug therapy, COVID-19, Telemedicine
- Abstract
The COVID-19 pandemic accelerated adaption of a telehealth care model. We studied the impact of telehealth on the management of atrial fibrillation (AF) by electrophysiology providers in a large, multisite clinic. Clinical outcomes, quality metrics, and indicators of clinical activity for patients with AF during the 10-week period of March 22, 2020 to May 30, 2020 were compared with those from the 10-week period of March 24, 2019 to June 1, 2019. There were 1946 unique patient visits for AF (1,040 in 2020 and 906 in 2019). During 120 days after each encounter, there was no difference in hospital admissions (11.7% vs 13.5%, p = 0.25) or emergency department visits (10.4% vs 12.5%, p = 0.15) in 2020 compared with 2019. There was a total of 31 deaths within 120 days, with similar rates in 2020 and 2019 (1.8% vs 1.3%, p = 0.38). There was no significant difference in quality metrics. The following clinical activities occurred less frequently in 2020 than in 2019: offering escalation of rhythm control (16.3% vs 23.3%, p <0.001), ambulatory monitoring (29.7% vs 51.7%, p <0.001), and electrocardiogram review for patients on antiarrhythmic drug therapy (22.1% vs 90.2%, p <0.001). Discussions about risk factor modification were more frequent in 2020 compared with 2019 (87.9% vs 74.8%, p <0.001). In conclusion, the use of telehealth in the outpatient management of AF was associated with similar clinical outcomes and quality metrics but differences in clinical activity compared with traditional ambulatory encounters. Longer-term outcomes warrant further investigation., Competing Interests: Disclosures The authors have no conflicts of interest to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2023
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39. High-Performance Thermoplastics from a Unique Bicyclic Lignin-Derived Diol.
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Wu X, De Bruyn M, Trimmel G, Zangger K, and Barta K
- Abstract
Polyesters are an important class of thermoplastic polymers, and there is a clear demand to find high-performing, recyclable, and renewable alternatives. In this contribution, we describe a range of fully bio-based polyesters obtained upon the polycondensation of the lignin-derived bicyclic diol 4,4'-methylenebiscyclohexanol (MBC) with various cellulose-derived diesters. Interestingly, the use of MBC in combination with either dimethyl terephthalate (DMTA) or dimethyl furan-2,5-dicarboxylate (DMFD) resulted in polymers with industrially relevant glass transition temperatures in the 103-142 °C range and high decomposition temperatures (261-365 °C range). Since MBC is obtained as a mixture of three distinct isomers, in-depth NMR-based structural characterization of the MBC isomers and thereof derived polymers is provided. Moreover, a practical method for the separation of all MBC isomers is presented. Interestingly, clear effects on the glass transition, melting, and decomposition temperatures, as well as polymer solubility, were evidenced with the use of isomerically pure MBC. Importantly, the polyesters can be efficiently depolymerized by methanolysis with an MBC diol recovery yield of up to 90%. The catalytic hydrodeoxygenation of the recovered MBC into two high-performance specific jet fuel additives was demonstrated as an attractive end-of-life option., Competing Interests: The authors declare no competing financial interest., (© 2023 American Chemical Society.)
- Published
- 2023
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40. Novel stereoisomeric lignin-derived polycarbonates: towards the creation of bisphenol polycarbonate mimics.
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Wu X, Xu D, De Bruyn M, Trimmel G, and Barta K
- Abstract
In this work, we have described a family of bio-based polycarbonates (PC-MBC) based on the unique lignin-derived aliphatic diol 4,4'-methylenebiscyclohexanol (MBC) that was sustainably sourced from lignin oxidation mixture. The detailed structure analysis of these polycarbonates has been confirmed by a series of 2D NMR (HSQC and COSY) characterizations. Depending on the stereoisomerism of MBC, the PC-MBC displayed a wide achievable T
g range of 117-174 °C and high Td5% of >310 °C by variation of the ratio of the stereoisomers of MBC, offering great substitution perspectives towards a bisphenol-containing polycarbonates. Nonetheless, the most here presented PC-MBC polycarbonates were film-forming and transparent., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2023
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41. Corticosteroid exposure and cumulative effects in patients with eczema: Results from a patient survey.
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Barta K, Fonacier LS, Hart M, Lio P, Tullos K, Sheary B, and Winders TA
- Subjects
- Child, Adult, Humans, Adrenal Cortex Hormones adverse effects, Administration, Topical, Glucocorticoids therapeutic use, Eczema drug therapy, Eczema epidemiology, Dermatologic Agents
- Abstract
Background: Individuals with eczema may have substantial lifetime corticosteroid exposure, increasing the risk of corticosteroid-related side effects., Objective: To conduct a patient survey evaluating corticosteroid exposure and its cumulative effects in individuals with eczema., Methods: The multinational online survey was conducted between November 5, 2020, and January 11, 2021. Participants were aged 18 years or older and a patient (n = 1889) or a caregiver of a child (n = 271) diagnosed with having eczema by a medical professional., Results: All participants reported using corticosteroids. Average duration of topical corticosteroid (TCS) use was 15.3 years in adults and 3.6 years in children; 75% used TCS 1 to 2 times a day and 50% applied TCS 15 to 30 days/mo. Frequency and duration could not be determined by varying prescription TCS potencies. Oral corticosteroid use was reported by 36% of the participants (23% for eczema), with a lifetime average of 8.4 courses in adults and 8.1 courses in children. Corticosteroids for non-eczema atopic conditions were reported by 49% of the participants. In participants using TCS, 83% of adults and 64% of children experienced worsening symptoms over time. Development of new symptoms and conditions increased with a greater number of corticosteroid treatments and longer duration of TCS use but may have been owing to eczema progression. Symptoms consistent with topical steroid withdrawal syndrome after TCS discontinuation were reported by many participants., Conclusion: Reported substantial corticosteroid exposure throughout their lifetime eczema experience placed participants at risk of negative outcomes. Corticosteroids are a critical component of eczema treatment for many patients. However, careful corticosteroid prescribing practices and monitoring are needed to avoid side effects. When possible, corticosteroid-sparing strategies should be explored., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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42. The quantitative impact of atopic dermatitis on caregivers across multiple life domains.
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Kim RW, Barta K, Begolka WS, Capozza K, Eftekhari S, Tullos K, Tomaszewski N, Snell-Rood C, and Abuabara K
- Subjects
- Humans, Quality of Life, Caregivers, Dermatitis, Atopic
- Published
- 2022
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43. Qualitative analysis of the impact of atopic dermatitis on caregivers.
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Kim RW, Barta K, Begolka WS, Capozza K, Eftekhari S, Tullos K, Tomaszewski N, Snell-Rood C, and Abuabara K
- Subjects
- Humans, Surveys and Questionnaires, Quality of Life, Caregivers, Dermatitis, Atopic therapy
- Published
- 2022
- Full Text
- View/download PDF
44. High yield production of 1,4-cyclohexanediol and 1,4-cyclohexanediamine from high molecular-weight lignin oil.
- Author
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Wu X, De Bruyn M, Hulan JM, Brasil H, Sun Z, and Barta K
- Abstract
The complete utilization of all lignin depolymerization streams obtained from the reductive catalytic fractionation (RCF) of woody biomass into high-value-added compounds is a timely and challenging objective. Here, we present a catalytic methodology to transform beech lignin-derived dimers and oligomers (DO) into well-defined 1,4-cyclohexanediol and 1,4-cyclohexanediamine. The latter two compounds have vast industrial relevance as monomers for polymer synthesis as well as pharmaceutical building blocks. The proposed two-step catalytic sequence involves the use of the commercially available RANEY® Ni catalyst. Therefore, the first step involves the efficient defunctionalization of lignin-derived 2,6-dimethoxybenzoquinone (DMBQ) into 1,4-cyclohexanediol (14CHDO) in 86.5% molar yield, representing a 10.7 wt% yield calculated on a DO weight basis. The second step concerns the highly selective amination of 1,4-cyclohexanediol with ammonia to give 1,4-cyclohexanediamine (14CHDA) in near quantitative yield. The ability to use RANEY® Ni and ammonia in this process holds great potential for future industrial synthesis of 1,4-cyclohexanediamine from renewable resources., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)
- Published
- 2022
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45. A Diamine-Oriented Biorefinery Concept Using Ammonia and Raney Ni as a Multifaceted Catalyst.
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Wu X, De Bruyn M, and Barta K
- Abstract
Diamines are important industrial chemicals. In this paper we outline the feasibility of lignocellulose as a source of diol-containing molecules. We also illustrate the possibility of turning these diols into their diamines in good to excellent yields. Central to these transformations is the use of commercially available Raney Ni. For diol formation, the Raney Ni engages in hydrogenation and often also demethoxylation, that way funneling multiple components to one single molecule. For diamine formation, Raney Ni catalyzes hydrogen-borrowing mediated diamination in the presence of NH
3 ., (© 2022 The Authors. Chemie Ingenieur Technik published by Wiley-VCH GmbH.)- Published
- 2022
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- View/download PDF
46. One-Pot Catalytic Conversion of Lignin-Derivable Guaiacols and Syringols to Cyclohexylamines.
- Author
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Wu X, De Bruyn M, and Barta K
- Subjects
- Guaiacol, Pharmaceutical Preparations, Pyrogallol analogs & derivatives, Cyclohexylamines, Lignin
- Abstract
Cyclic primary amines are elementary building blocks to many fine chemicals, pharmaceuticals, and polymers. Here, a powerful one-pot Raney Ni-based catalytic strategy was developed to transform guaiacol into cyclohexylamine using NH
3 (7 bar) and H2 (10 bar) in up to 94 % yield. The methodology was extendable to the conversion of a wider range of guaiacols and syringols into their corresponding cyclohexylamines. Notably, a crude bio-oil originating from the reductive catalytic fractionation of birch lignocellulose was transformed into a product mixture rich in 4-propylcyclohexylamine, constituting an interesting case of catalytic funneling. The isolated yield of the desired 4-propylcyclohexylamine reached as high as 7 wt % (on lignin basis). Preliminary mechanistic studies pointed at the consecutive occurrence of three key catalytic transformations, namely, demethoxylation, hydrogenation, and amination., (© 2022 The Authors. ChemSusChem published by Wiley-VCH GmbH.)- Published
- 2022
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47. Primary amines from lignocellulose by direct amination of alcohol intermediates, catalyzed by RANEY® Ni.
- Author
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Wu X, De Bruyn M, and Barta K
- Abstract
Primary amines are crucially important building blocks for the synthesis of a wide range of industrially relevant products. Our comprehensive catalytic strategy presented here allows diverse primary amines from lignocellulosic biomass to be sourced in a straightforward manner and with minimal purification effort. The core of the methodology is the efficient RANEY® Ni-catalyzed hydrogen-borrowing amination (with ammonia) of the alcohol intermediates, namely alkyl-phenol derivatives as well as aliphatic alcohols, obtained through the two-stage LignoFlex process . Hereby the first stage entails the copper-doped porous metal oxide (Cu20PMO) catalyzed reductive catalytic fractionation ( RCF ) of pine lignocellulose into a crude bio-oil, rich in dihydroconiferyl alcohol ( 1G ), which could be converted into dihydroconiferyl amine ( 1G amine ) in high selectivity using ammonia gas, by applying our selective amination protocol. Notably also, the crude RCF -oil directly afforded 1G amine in a high 4.6 wt% isolated yield (based on lignin content). Finally it was also shown that the here developed Ni-catalysed heterogeneous catalytic procedure was equally capable of transforming a range of aliphatic linear/cyclic primary/secondary alcohols - available from the second stage of the LignoFlex procedure - into their respective primary amines., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2022
- Full Text
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48. The Multidimensional Burden of Atopic Dermatitis Among Adults: Results From a Large National Survey.
- Author
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Elsawi R, Dainty K, Smith Begolka W, Barta K, Butler L, Capozza K, Eftekhari S, Tullos KZ, Wu W, and Drucker AM
- Subjects
- Adult, Cost of Illness, Female, Humans, Male, Quality of Life, Severity of Illness Index, Surveys and Questionnaires, Dermatitis, Atopic drug therapy
- Abstract
Importance: Atopic dermatitis (AD) is long term and burdensome. Studies investigating disease burden in adults are limited in scope with gaps in understanding of the adult patient lived experience., Objective: To describe the multidimensional burden of AD among mainly US adults., Design, Setting, and Participants: This survey study for an externally led patient-focused drug development meeting with the US Food and Drug Administration on adult patients with AD was conducted between August 1, 2019, and October 11, 2019. Data were analyzed betwean March 26, 2021, and June 29, 2021., Main Outcomes and Measures: We used multivariable ordinal regression to assess associations between demographic and clinical variables and patient-reported overall AD impact scores (ordinal scale from 1 [no impact] to 5 [significant impact])., Results: Among 1065 survey respondents, 114 (11%) were aged 18 to 24 years, 235 (22%) were 25 to 34 years, 242 (23%) were 35 to 50 years, 288 (27%) were 51 to 64 years, and 186 (17%) were aged 65 years or older; 881 (83%) were women. Four hundred eighty-nine (46%) participants reported low-moderate AD impact scores (2-3), 544 (51%) reported high-significant impact scores (4-5), whereas 32 (3%) reported no association of AD with disease burden (impact score, 1). Variables strongly associated with overall impact scores were current AD severity (moderate: OR, 4.13; 95% CI, 2.94-5.79; severe: OR, 13.63; 95% CI, 8.65-21.50 vs mild), and time spent managing AD (11-20 hours: OR, 2.67; 95% CI, 1.77-4.03, ≥21 hours: OR, 5.34; 95% CI, 3.22-8.85, vs <5 hours)., Conclusions and Relevance: In this survey study, AD severity and time spent managing symptoms showed the strongest associations with disease burden. This analysis highlights the multidimensional burden of AD in adults and emphasizes the need for more effective treatment strategies that reduce the time patients spend managing their AD.
- Published
- 2022
- Full Text
- View/download PDF
49. Fully lignocellulose-based PET analogues for the circular economy.
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Wu X, Galkin MV, Stern T, Sun Z, and Barta K
- Subjects
- Biomass, Polymers, Lignin chemistry, Polyethylene Terephthalates
- Abstract
Polyethylene terephthalate is one of the most abundantly used polymers, but also a significant pollutant in oceans. Due to growing environmental concerns, polyethylene terephthalate alternatives are highly sought after. Here we present readily recyclable polyethylene terephthalate analogues, made entirely from woody biomass. Central to the concept is a two-step noble metal free catalytic sequence (Cu20-PMO catalyzed reductive catalytic fractionation and Raney Ni mediated catalytic funneling) that allows for obtaining a single aliphatic diol 4-(3-hydroxypropyl) cyclohexan-1-ol in high isolated yield (11.7 wt% on lignin basis), as well as other product streams that are converted to fuels, achieving a total carbon yield of 29.5%. The diol 4-(3-hydroxypropyl) cyclohexan-1-ol is co-polymerized with methyl esters of terephthalic acid and furan dicarboxylic acid, both of which can be derived from the cellulose residues, to obtain polyesters with competitive Mw and thermal properties (T
g of 70-90 °C). The polymers show excellent chemical recyclability in methanol and are thus promising candidates for the circular economy., (© 2022. The Author(s).)- Published
- 2022
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- View/download PDF
50. A molecular motor from lignocellulose.
- Author
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Freese T, Fridrich B, Crespi S, Lubbe AS, Barta K, and Feringa BL
- Abstract
Lignin is the largest natural source of functionalized aromatics on the planet, therefore exploiting its inherent structural features for the synthesis of aromatic products is a timely and ambitious goal. While the recently developed lignin depolymerization strategies gave rise to well-defined aromatic platform chemicals, the diversification of these structures, especially toward high-end applications is still poorly addressed. Molecular motors and switches have found widespread application in many important areas such as targeted drug delivery systems, responsive coatings for self-healing surfaces, paints and resins or muscles for soft robotics. They typically comprise a functionalized aromatic backbone, yet their synthesis from lignin has not been considered before. In this contribution, we showcase the synthesis of a novel light-driven unidirectional molecular motor from the specific aromatic platform chemical 4-(3-hydroxypropyl)-2,6-dimethoxyphenol (dihydrosynapyl alcohol) that can be directly obtained from lignocellulose via a reductive catalytic fractionation strategy. The synthetic path takes into account the principles of green chemistry and aims to maintain the intrinsic functionality of the lignin-derived platform molecule., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2022
- Full Text
- View/download PDF
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