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11.
Iwona Krela-Kazmierczak Aleksandra Szymczak-Tomczak Maciej Tomczak Liliana Lykowska-Szuber Piotr Eder Marcin A. Kucharski Kamila Stawczyk-Eder Katarzyna Waszak Jacek Karczewski Agnieszka Dobrowolska 《Archives of Medical Science》2021,17(3):662
IntroductionIn inflammatory bowel diseases (IBD), osteopenia and osteoporosis constitute a significant medical problem. Cytokines, especially IL-17, play an important role in the pathogenesis of IBD and osteoporosis. Vitamin D is a regulator of bone metabolism, and helps maintain immune system homeostasis.Material and methodsThe research sample consisted of 208 persons: 83 patients (age 35 ±11.99 years) with Crohn’s disease (CD); 86 patients (age 39.58 ±14.74 years) with ulcerative colitis (UC); and 39 persons (age 30.74 ±8.63 years) in the control group (CG). Clinical data on bone mineral density of the lumbar spine (L2-L4), bone mineral density of the femoral neck (FN), and body mass index (BMI) were collected. 25OHD and IL-17 serum concentrations were also measured.ResultsBody mass index (kg/m2) results: in CD, 21.51 ±3.68; in UC, 23.31 ±4.38; and in CG, 24.57 ±3.45 (p < 0.01). Densitometry results for L2–L4 T-score SD: in CD –0.83 ±1.45; in UC –0.47 ±1.15; in CG 0.09 ±0.70. Densitometry results for FN T-score SD: in CD –0.62 ±1.26; in UC –0.29±1.17; in CG 0.41 ±1.03 25OHD (ng/ml) serum concentrations: in CD, 21.33±12.50; in UC, 22.04±9.56; in CG, 21.56±9.11 (ns). IL-17 (pg/ml) serum concentrations: in CD, 8.55±10.99; in UC, 11.67±12.97; in CG, 5.16±9.11 (ns).ConclusionsInflammatory bowel diseases patients and persons from the CG did not differ in vitamin D or IL-17 levels. Patients with a mild course of the disease had a higher vitamin D concentration and bone mineral density. In UC, higher vitamin D concentrations were associated with lower IL-17 concentrations. The IBD patients with a severe course of the disease had a lower body mass than those in the CG and the patients with a mild course of the disease. 相似文献
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Maria Kuraska Hynek Bene Kamila Saasiska Aleksander Prociak Elbieta Malewska Krzysztof Polaczek 《Materials》2020,13(23)
This work presents the cell structure and selected properties of polyurethane (PUR) foams, based on two types of hydroxylated used cooking oil and additionally modified with three different flame retardants. Bio-polyols from municipal waste oil with different chemical structures were obtained by transesterification with triethanolamine (UCO_TEA) and diethylene glycol (UCO_DEG). Next, these bio-polyols were used to prepare open-cell polyurethane foams of very low apparent densities for thermal insulation applications. In order to obtain foams with reduced flammability, the PUR systems were modified with different amounts (10–30 parts per hundred polyol by weight—php) of flame retardants: TCPP (tris(1-chloro-2-propyl)phosphate), TEP (triethyl phosphate), and DMPP (dimethyl propylphosphonate). The flame retardants caused a decrease of the PUR formulations reactivity. The apparent densities of all the foams were comparable in the range 12–15 kg/m3. The lowest coefficients of thermal conductivity were measured for the open-cell PUR foams modified with DMPP. The lowest values of heat release rate were found for the foams based on the UCO_TEA and UCO_DEG bio-polyols that were modified with 30 php of DMPP. 相似文献
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Valery N. Bliznyuk Kamila Koaciska Alexander A. Pud Nikolay A. Ogurtsov Yuriy V. Noskov Brian A. Powell Timothy A. DeVol 《RSC advances》2019,9(52):30052
Sorption properties of polydopamine (PDA) for uranium and plutonium from an aqueous environment are reported at three different pH values (2, 4 and 6.5–7). In addition to deionized (DI) water, artificial groundwater (GW) and seawater (SW) were used with U uptake close to 100% in each case. PDA polymer has been identified as a material with extremely high sorption capacity Qmax ∼500 mg g−1 of the polymer at pH 6.5 and high selectivity for uranium. Similar high sorption properties are revealed for plutonium uptake. PDA-uranyl and PDA-plutonium interactions responsible for the observed adsorption processes have been addressed with a set of experimental techniques including FTIR spectroscopy, electron microscopy and cyclic voltammetry.We demonstrate that complexation of pure polydopamine with uranium and plutonium species allows efficient retention of these actinides from groundwater and seawater. 相似文献
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Kamila Rosamilia Kantovitz Fernanda Miori Pascon Gisele Maria Correr Ana Flávia Sanches Borges Marinês Nobre Dos Santos Uchôa 《Acta odontologica Scandinavica》2013,71(6):376-383
Objective. In this in vitro study we evaluated the enamel mineral loss effect of fluoride-containing and non-fluoride-containing materials at different distances from the sealant margin, and verified the fluoride-releasing capability of these materials. Material and methods. Extracted molars were randomly assigned into nine groups (n=12): Concise (C), FluroShield (F), Helioseal Clear Chroma (H), Vitremer (V), Fuji II-LC (FII), Ketac Molar (KM), Fuji IX (FIX), Single Bond (SB), and Clearfil Protect Bond (CF). All groups were subjected to thermo and pH cycling. Enamel mineral loss was evaluated by cross-section micro-hardness analysis at distances: ?100?µm, 0?µm, 100?µm, 200?µm. The mineral loss data were analyzed using a multi-factor ANOVA with split-plot design, and fluoride-released data were submitted to ANOVA and Tukey tests. Results. FIX demonstrated a lower mineral loss than C, F, and H, but did not differ from the SB, CF, V, FII, and KM groups, which also demonstrated no difference among them. C, F, H, and V presented the highest mineral loss, with no difference among them. V did not differ from the other groups (p>0.05). Regarding the different distances from the sealant margin, ?100?µm presented the lowest mineral loss. FIX showed the highest fluoride release on the 7th and 14th days of evaluation, while CF showed high fluoride release only on the 7th day. Conclusion. Resin sealant did not prevent enamel mineral loss, contrary to glass-ionomer cement, which showed the highest capacity for fluoride release. It is not exclusively the presence of fluoride in a material's composition that indicates its capability to interfere with the development of enamel caries-like lesions. 相似文献
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Carolina Luna Kamila Mizerska Susana Quirce Carlos Belmonte Juana Gallar María del Carmen Acosta Víctor Meseguer 《Investigative ophthalmology & visual science》2021,62(1)
PurposeTo test the effect of different sodium channel blockers on the electrical activity of corneal nociceptors in intact and surgically injured corneas.MethodsIn anesthetized guinea pigs, a 4-mm diameter corneal flap was performed in one eye at a midstromal depth using a custom-made microkeratome. At different times after surgery (3 hours to 15 days), the electrical activity of corneal nociceptor fibers was recorded from ciliary nerve filaments in the superfused eye in vitro. Mechanical threshold was measured using calibrated von Frey hairs; chemical stimulation was performed applying 30-second CO2 gas pulses. The characteristics of the spontaneous and stimulus-evoked activity of corneal nociceptors recorded from intact and lesioned corneas, before and after treatment with the sodium channel blockers lidocaine, carbamazepine, and amitriptyline, were compared.ResultsNo spontaneous or stimulus-evoked impulse activity was detected inside the flap at any of the studied time points. However, both were recorded from mechanonociceptor and polymodal nociceptors fibers in the surrounding corneal tissue, being significantly higher (sensitization) 24 to 48 hours after surgery. In these fibers, none of the tested drugs affected mechanical threshold, but they significantly reduced the CO2 response of polymodal nociceptors of intact and injured corneas. Likewise, they diminished significantly the transient increase in spontaneous and stimulus-evoked activity of sensitized polymodal nociceptors.ConclusionsNa+ channel blockers decrease the excitability of intact and sensitized corneal nociceptor fibers, thus acting as potential tools to attenuate their abnormal activity, which underlies the spontaneous pain, hyperalgesia, and allodynia often accompanying surgical corneal lesions, as occurs after photorefractive surgery. 相似文献