The relationship between lower extremity arterial properties and aortic stiffness and their effect on cardiovascular risk

Poměr systolického tlaku na kotníku k systolickému tlaku na paži (poměr kotník-paže - ABI) je využíván v diagnostice ischemické choroby dolních končetin. Jeho snížená hodnota je známkou obstrukce lumina tepny, zatímco abnormálně zvýšená hodnota je způsobena inkompresibilitou tepen dolních končetin. Zatímco zvýšená tuhost aorty, měřená jako rychlost pulzové vlny mezi karotickou a femorální tepnou, je schopna predikovat kardiovaskulární riziko, zvýšená tuhost tepen dolních končetin, měřená jako rychlost pulzové vlny, nemá nezávislou prediktivní hodnotu. Přesto je inkompresibilita tepen dolních končetin stanovená pomocí ABI v nezávislém vztahu se zvýšeným kardiovaskulárním rizikem. Cílem naší práce bylo zjistit vztah mezi vlastnostmi tepen dolních končetin a aortální tuhostí a jejich vliv na kardiovaskulární riziko. Zjistili jsme, že výsledky oscilometrické a dopplerovské metody měření ABI nelze zaměňovat, protože oscilometrická metoda systematicky nadhodnocuje nízké hodnoty ABI a podhodnocuje vysoké hodnoty ABI. Proto je pro diagnostiku inkompresibility tepen dolních končetin vhodnější dopplerovská metoda měření ABI. Dále jsme ukázali, že věk a kardiovaskulární rizikové faktory mají menší vliv na tuhost tepen dolních končetin než na tuhost aorty. V naší studii zvýšený ABI jako projev inkompresibility tepen...The ratio of systolic blood pressure at the ankle to arm systolic pressure (ankle- brachial index - ABI) is used in the diagnosis of peripheral vascular disease. While its reduced value suggests obstruction of the arterial lumen, an abnormally elevated value is due to incompressibility of lower extremity arteries. While increased stiffness of the aorta, measured as carotid-femoral pulse wave velocity, is able to predict cardiovascular risk, increased pulse wave velocity of the leg arteries has no independent predictive value. Despite that, incompressibility of lower extremity arteries, diagnosed using ABI measurement, is independently associated with increased cardiovascular risk. The aim of our study was to determine the relationship between the characteristics of lower limb arteries and aortic stiffness, and their impact on cardiovascular risk. Our study showed that the results of oscillometric and Doppler ABI measurement methods are not interchangeable, because the oscillometric method systematically overestimates low values and underestimates high ABI values. Therefore, the diagnosis of lower limb arteries incompressibility should be based on the Doppler method of ABI measurement. Furthermore, we showed that age and cardiovascular risk factors have only a small effect on lower extremity arteries, but a...externí pracovištěexternal workplacesFirst Faculty of Medicine1. lékařská fakult

Synergetic effects of LiFe0.3Mn0.7PO4–LiMn1.9Al0.1O4 blend electrodes

AbstractComposite cathodes are prepared by blending the olivine LiFe0.3Mn0.7PO4 (LFMP) and spinel LiMn1.9Al0.1O4 (LMO) in order to combine the high capacity of LFMP with the rate capability of the spinel. While tap density, capacity and energy density show a linear dependency on the blend ratio, a remarkable synergetic effect between LFMP and LMO improving the electrochemical performance at higher C-rates is demonstrated. Potential curves of blend electrodes at rates of 3C reveal a less pronounced polarization for the Mn2+/3+ plateau than expected from theoretical calculations. This buffer effect is also observed for high current pulses (5C) where blend electrodes resemble the behavior of pure spinel electrodes. In terms of power density at high states of charge (SoC), the performance of the Blend(50LFMP/50LMO cap%) exceeds even that of pure spinel. In addition, the spinel-related manganese dissolution can be drastically reduced by blending spinel with LFMP. This study shows the expected and synergetic effects of LFMP/spinel blends and compares the results with theoretical calculations

The effectiveness of pollen allergen immunotherapy on allergic rhinitis over 18 years: A national cohort study in Denmark

BACKGROUND: Because long-term effectiveness of pollen allergen immune therapy (AIT) for allergic rhinitis (AR) is not well-described, we studied effectiveness over 18 years in Denmark.METHODS: A register-based cohort study using data on filled prescriptions, 1995-2016, Denmark. In a cohort of 1.1 million intranasal corticosteroid inhaler users (proxy for AR), we matched users treated with grass, birch or mugwort AIT 1:2 with non-treated users on baseline year and 24 characteristics in the 3 years prior to baseline. The primary outcome was the odds ratio (OR) of using anti-allergic nasal inhaler during the pollen season in the treated versus non-treated group by years since baseline.RESULTS: Among 7760 AR patients treated with pollen AIT, the OR of using nasal inhaler 0-5 years after baseline was reduced when compared with 15,520 non-treated AR individuals (0-2 years, OR 0.84 (0.81-0.88); 3-5 years, OR 0.88 (0.84-0.92)), but was close to unity or higher thereafter (6-9 years, OR 1.03 (0.97-1.08); 10-18 years, OR 1.18 (1.11-1.26)). In post hoc analyses, results were more consistent for those who already had 3 of 3 baseline years of use, and in patients using nasal inhaler in the latest pollen season (0-2 years, OR 0.76 (0.72-0.79); 3-5 years OR 0.86 (0.81-0.93); 6-9 years, OR 0.94 (0.87-1.02); 10-18 years, OR 0.94 (0.86-1.04)) as opposed to no such use.CONCLUSIONS: Patients treated with pollen AIT in routine care to a higher degree stopped using anti-allergic nasal inhaler 0-5 years after starting the standard 3 years of therapy, and not beyond 5 years. Post hoc analyses suggested effectiveness was more consistent among patients with persistent AR.</p

Chemical induced delithiation on LixMnPO4: an investigation about the phase structure

Understanding the LiMnPO4/MnPO4 phase transition is of great interest in order to further improve the electrochemical performance of this cathode material. Since most of the previously published literature deals with characterization of chemically delithiated Lix MnPO4, the aim of this study is to compare and study the composition and structure of the different phases that are generated upon chemical delithiation of LixMnPO4. Bare and carboncoated lithium manganese phos-phates are prepared via a combined coprecipitation-calcination method. Partial delithiation to two different degrees of delithiation Lix MnPO4 (x = 0.24/0.23 and 0.45) for carbon-coated and/or bare materials is achieved using an excess of nitro-nium tetrafluoroborate in acetonitrile. The effect of carboncoating has been also considered. Standard materials characterization with XRD (X-Ray Diffraction) and ICPOES (Inductive Coupled Plasma spectrometry and Optical Emission Spectroscopy) analysis are in accordance with literature data, but further cerimetric analysis revealed serious deviations, showing differences in the degree of delithiation to the average degree of oxidation. A structural characterization of the atomic and electronic local structure of the materials is also ob-tained using XAS (X-ray Absorption Spectroscopy) technique

Clinical impact and predictors of carotid artery in-stent restenosis

To assess the incidence and clinical significance as well as predictors of in-stent restenosis (ISR) after carotid artery stenting (CAS) diagnosed with serial duplex sonography investigations. We analyzed 215 CAS procedures that had clinical and serial carotid duplex ultrasound investigations. The incidence of in-stent restenosis (ISR) and periprocedural as well as long-term clinical complications were recorded. The influence of an ISR on clinical complication was analyzed using Kaplan-Meier curves and clinical risk factors for the development of an ISR with multivariate logistic regression. During a median follow-up time of 33.4 months (interquartile range 15.3–53.7) an ISR of ≥70% was detected in 12 (6.1%) of 215 arteries (mean age of 68.1 ± 9.8 years, 71.6% male). The combined stroke and death rate during long-term follow-up was significantly higher in the group with an ISR [odds ratio (OR): 3.59, 95% confidence interval (CI): 1.50–8.59, p = 0.004]. After applying multivariate logistic regression analysis contralateral carotid occlusion (OR 10.11, 95% CI 2.06–49.63, p = 0.004), carotid endarterectomy (CEA) restenosis (OR 8.87, 95% CI 1.68–46.84, p = 0.010) and postprocedural carotid duplex ultrasound with a PSV ≥120 cm/s (OR 6.33, 95% CI 1.27–31.44, p = 0.024) were independent predictors of ISR. ISR after CAS during long-term follow-up is associated with a higher proportion of clinical complications. A close follow-up is suggested especially in those patients with the aforementioned independent predictors of an ISR. Against the background of a lacking established treatment of ISR, these findings should be taken into account when offering CAS as a treatment alternative to CEA

Effect of induction therapy on the expression of molecular markers associated with rejection and tolerance

Background Induction therapy can improve kidney transplantation (KTx) outcomes, but little is known about the mechanisms underlying its effects. Methods The mRNA levels of T cell-related genes associated with tolerance or rejection (CD247, GZMB, PRF1, FOXP3, MAN1A1, TCAIM, and TLR5) and lymphocyte subpopulations were monitored prospectively in the peripheral blood of 60 kidney transplant recipients before and 7, 14, 21, 28, 60, 90 days, 6 months, and 12 months after KTx. Patients were treated with calcineurin inhibitor- based triple immunosuppression and induction with rabbit anti-thymocyte globulin (rATG, n = 24), basiliximab (n = 17), or without induction (no- induction, n = 19). A generalized linear mixed model with gamma distribution for repeated measures, adjusted for rejection, recipient/donor age and delayed graft function, was used for statistical analysis. Results rATG treatment caused an intense reduction in all T cell type population and natural killer (NK) cells within 7 days, then a slow increase and repopulation was observed. This was also noticed in the expression levels of CD247, FOXP3, GZMB, and PRF1. The basiliximab group exhibited higher CD247, GZMB, FOXP3 and TCAIM mRNA levels and regulatory T cell (Treg) counts than the no-induction group. The levels of MAN1A1 and TLR5 mRNA expressions were increased, whereas TCAIM decreased in the rATG group as compared with those in the no-induction group. Conclusion The rATG induction therapy was associated with decreased T and NK cell-related transcript levels and with upregulation of two rejection- associated transcripts (MAN1A1 and TLR5) shortly after KTx. Basiliximab treatment was associated with increased absolute number of Treg cells, and increased level of FOXP3 and TCAIM expression

Deriving structure-performance relations of chemically modified chitosan binders for sustainable high-voltage LiNi0.5Mn1.5O4 cathode

Invited for this month's cover picture is the group of Prof. Dr. Stefano Passerini. The front cover illustrates the use of citric acid (co-)crosslinked bio-derived polymers, with chitosan and guar gum, as water-soluble binders for sustainable lithium-ion battery cathodes. Read the full text of the Article at 10.1002/batt.201900140. © 2020 Wiley-VCH Verlag GmbH &amp; Co. KGaA, Weinhei

Deriving Structure-Performance Relations of Chemically Modified Chitosan Binders for Sustainable High-Voltage LiNi0.5_{0.5}Mn1.5_{1.5}O4_{4} Cathodes

The implementation of aqueous electrode processing for lithium‐ion positive electrodes is key towards the realization of environmentally benign and cheap battery production. One of the water‐soluble binders that has attracted most attention is chitosan, the second‐most abundant natural biopolymer. Herein, the use of chitosan for high‐voltage, cobalt‐free LiNi$_{0.5}$Mn$_{1.5}$O$_{4}$ cathodes is reported for the first time. A detailed comparison of three different grades of chitosan with varying chain length and degrees of deacetylation (DD) is provided to explore the impact of these properties on the electrochemical performance. In fact, bio‐derived chitosan with a relatively lower DD outperforms synthetic chitosan‐especially after crosslinking with citric acid‐yielding about 10 % higher capacities. Higher molecular weight appears additionally advantageous for the cycling stability. Finally, guar gum is employed as slurry thickener, co‐crosslinking with chitosan. This allows for achieving 50 % higher mass loadings than for chitosan only and stable capacities above 130 and 120 mAh g$^{-1}$ at C/3 and 1 C, respectively

Deriving structure‐performance relations of chemically modified chitosan binders for sustainable high‐voltage LiNi0.5Mn1.5O4 cathodes

The implementation of aqueous electrode processing for lithium-ion positive electrodes is key towards the realization of environmentally benign and cheap battery production. One of the water-soluble binders that has attracted most attention is chitosan, the second-most abundant natural biopolymer. Herein, the use of chitosan for high-voltage, cobalt-free LiNi0.5Mn1.5O4 cathodes is reported for the first time. A detailed comparison of three different grades of chitosan with varying chain length and degrees of deacetylation (DD) is provided to explore the impact of these properties on the electrochemical performance. In fact, bio-derived chitosan with a relatively lower DD outperforms synthetic chitosan-especially after crosslinking with citric acid-yielding about 10 % higher capacities. Higher molecular weight appears additionally advantageous for the cycling stability. Finally, guar gum is employed as slurry thickener, co-crosslinking with chitosan. This allows for achieving 50 % higher mass loadings than for chitosan only and stable capacities above 130 and 120 mAh g(-1) at C/3 and 1 C, respectively