Adhesive properties of endothelial cells are influenced by the thioldisulfide balance. However, the molecular mechanism of this effect is unclear, although recent observations indicate that integrin receptors may be direct targets for redox modulation. The purpose of this study was to examine whether protein disulfide isomerase (PDI) is directly involved in this process. As manganese ions are known to affect the thioldisulfide balance and activate integrins to maximal affinity, we searched for PDI interactions with integrins, particularly with αVβ3, in Mn2+‐treated endothelial cells. By employing confocal microscopy, flow cytometry and coimmunoprecipitation experiments, we showed that exposure of endothelial cells to Mn2+ resulted in: (a) the appearance of surface protein thiol groups, which can be found in PDI and αVβ3, and both proteins colocalizing on the cellular surface; and (b) the formation of the PDI–αVβ3 complex, which dissociates upon reduction. In addition, PDI in a complex with αVβ3 induces conversion of the integrin to the ligand‐competent high‐affinity state, as evidenced by increased binding of vitronectin. The membrane‐impermeable sulfhydryl blockers 3‐N‐maleimidylpropionyl biocytin 3‐N‐maleimidylpropionyl biocytin and p‐chloromercuriphenyl sulfonate, as well as the PDI inhibitors bacitracin, MA3 018, and MA3 019, abolished the binding of vitronectin and LM609 to endothelial cells that is activated by Mn2+. Consistently, LM609 almost completely blocked binding of vitronectin to such cells. The formation of the PDI–αVβ3 stoichiometric complex was further demonstrated by surface plasmon resonance analysis, which showed that the initial reversible binding of PDI becomes irreversible in the presence of Mn2+, probably mediated by disulfide bonds. Thus, we show that Mn2+ simultaneously modulates the thiol isomerase activity of PDI that is bound to αVβ3 and induces its transition to the ligand‐competent state, suggesting an alternative mechanism of integrin regulation.

ObjectiveAcute single strenuous exercise increases circulating cell free DNA (cf DNA). We tested whether three repeated bouts of exhaustive exercise induced the cf DNA response without development of tolerance in healthy men.MethodsEleven average-trained men (age 34.0±5.2 years, body mass index 26.2±3.1 kg/m2, maximal oxygen consumption—VO2max 49.6±4.5 ml/kg*min) performed three treadmill exercise tests to exhaustion at speed corresponding to 70% VO2max separated by 72 hours of resting. Blood was collected before and after each bout of exercise for determination of cell free nuclear and mitochondrial DNA (cf n-DNA, cf mt-DNA) by real-time PCR, selected markers of muscle damage, and blood cell count.ResultsEach bout induced the increase (p<0.05) in plasma cf n-DNA: from 3.4±1.4 to 38.5±27.5, from 4.1±3.3 to 48.5±26.2, and 3.1±1.6 to 53.8±39.9 ng/mL after the first, second, and third exercise, respectively. In a congruent way, cf mt-DNA rose significantly after the second (from 229±216 to 450±228*103 GE/mL) and third bout of exercise (from 173±120 to 462±314*103 GE/mL).Pre-exercise cf mt-DNA decreased (p<0.05) by 2-times (from 355±219 before the first bout to 173±120*103 GE/mL before the third bout) over the study period and were accompanied by significant increase in white blood cells, platelets, creatine kinase, creatinine and lactate after each bout. However, the exercise induced percentage increment of cf n-DNA was always many times higher than corresponding increments of the afore-mentioned markers at any occasion.ConclusionsRepeated bouts of exhaustive exercise induced remarkable increase in circulating cf n-DNA without signs of tolerance development. Baseline cf mt-DNA decreased in response to series of strenuous exercise. Since percentage increments of cf n-DNA in response to exercise were many times higher than those observed for other markers, measurement of circulating cf n-DNA could be a sensitive tool for monitoring acute exercise effects in human body.

We have demonstrated that rapid consumption of apple juice increased plasma antioxidant activity in healthy subjects; this was caused by the fructose-induced rise of serum uric acid levels, but was not due to the presence of antioxidant polyphenols in juice. Thus, short-term consumption of apple juice seems not to be the effective dietary intervention to augment plasma antioxidant activity due to the concomitant possibility for uric acid to be a risk factor for several diseases, as verified by other authors.

Strawberries contain anthocyanins and ellagitanins which have antioxidant properties. We determined whether the consumption of strawberries increase the plasma antioxidant activity measured as the ability to decompose 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) in healthy subjects. The study involved 10 volunteers (age 41 ± 6 years, body weight 74.4 ± 12.7 kg) that consumed 500 g of strawberries daily for 9 days and 7 matched controls. Fasting plasma and spot morning urine samples were collected at baseline, during fruit consumption and after a 6 day wash-out period. DPPH decomposition was measured in both deproteinized native plasma specimens and pretreated with uricase (non-urate plasma). Twelve phenolics were determined with HPLC. Strawberries had no effect on the antioxidant activity of native plasma and circulating phenolics. Non-urate plasma DPPH decomposition increased from 5.7 ± 0.6% to 6.6 ± 0.6%, 6.5 ± 1.0% and 6.3 ± 1.4% after 3, 6 and 9 days of supplementation, respectively. The wash-out period reversed this activity back to 5.7 ± 0.8% (p<0.01). Control subjects did not reveal any changes of plasma antioxidant activity. Significant increase in urinary urolithin A and 4-hydroxyhippuric (by 8.7- and 5.9-times after 6 days of supplementation with fruits) was noted. Strawberry consumption can increase the non-urate plasma antioxidant activity which, in turn, may decrease the risk of systemic oxidants overactivity.

ObjectivesTo evaluate the effect of age and chosen factors related to aging such as dentition, muscle strength, and nutrition on masticatory muscles electromyographic activity during chewing in healthy elderly women.BackgroundWith longer lifespan there is a need for maintaining optimal quality of life and health in older age. Skeletal muscle strength deteriorates in older age. This deterioration is also observed within masticatory muscles.MethodsA total of 30 women, aged 68–92 years, were included in the study: 10 individuals had natural functional dentition, 10 were missing posterior teeth in the upper and lower jaw reconstructed with removable partial dentures, and 10 were edontoulous, using complete removable dentures. Surface electromyography was performed to evaluate masticatory muscles activity. Afterwards, measurement of masseter thickness with ultrasound imaging was performed, body mass index and body cell mass index were calculated, and isometric handgrip strength was measured.ResultsIsometric maximal voluntary contraction decreased in active masseters with increasing age and in active and passive temporalis muscles with increasing age and increasing body mass index. In active masseter, mean electromyographic activity during the sequence (time from the start of chewing till the end when the test food became ready to swallow) decreased with increasing age and during the cycle (single bite time) decreased with increasing age and increasing body mass index. In active and passive temporalis muscles, mean electromyographic activity during the sequence and the cycle decreased with increasing age, increasing body mass index, and loss of natural dentition. Individuals with natural dentition had significantly higher mean muscle activity during sequence and cycle in active temporalis muscles than those wearing full dentures and higher maximal activity during cycle in individuals with active and passive temporalis muscles than in complete denture wearers.ConclusionDecrease in electromyographic activity of masticatory muscles in elderly women is related to age, deterioration of dental status, and body mass index.

Recent evidence supports a role of protein-disulfide isomerase (PDI) in redox-controlled remodeling of the exofacial domains of ␣ IIb ␤ 3 in blood platelets. The aim of this study was to explain whether Ero1␣ can be responsible for extracellular reoxidation of the PDI active site. We showed that Ero1␣ can be found on platelets and is rapidly recruited to the cell surface in response to platelet agonists. It is physically associated with PDI and ␣ IIb ␤ 3 , as suggested by colocalization analysis in confocal microscopy and confirmed by immunoprecipitation experiments. Apart from monomeric oxidized Ero1␣, anti-␣ IIb ␤ 3 immunoprecipitates showed the presence of several Ero1␣-positive bands that corresponded to the complexes ␣ IIb ␤ 3 -PDIEro1␣, PDI-Ero1␣, and Ero1␣-Ero1␣ dimers. It binds more efficiently to the activated ␣ IIb ␤ 3 conformer, and its interaction is inhibited by RGD peptides. Ero1␣ appears to be involved in the regulation of ␣ IIb ␤ 3 receptor activity because of the following: (a) blocking the cell surface Ero1␣ by antibodies leads to a decrease in platelet aggregation in response to agonists and a decrease in fibrinogen and PAC-1 binding, and (b) transfection of MEG01 with Ero1␣ increases ␣ IIb ␤ 3 receptor activity, as indicated by increased binding of fibrinogen.

Strenuous exercise increases circulating cell free DNA (cfDNA) and stimulates blood phagocytes to generate reactive oxygen species (ROS) which may induce DNA strand breaks. We tested whether: (A) elevated cfDNA in response to three repeated bouts of exhaustive exercise has decreased integrity; (B) each bout of exercise increases luminol enhanced whole blood chemiluminescence (LBCL) as a measure of ROS production by polymorphonuclear leukocytes. Eleven men performed three treadmill exercise tests to exhaustion separated by 72 hours of resting. Pre- and post-exercise concentrations and integrity of cf nuclear and mitochondrial DNA (cf n-DNA, cf mt-DNA) and resting (r) and fMLP (n-formyl-methionyl-leucyl-phenylalanine)-stimulated LBCL were determined. Each bout increased concentrations of cf n-DNA by more than 10-times which was accompanied by about 2-times elevated post-exercise rLBCL and fMLP-LBCL. Post-exercise cf n-DNA integrity (integrity index, I229/97) decreased after the first (0.59 ± 0.19 vs. 0.48 ± 0.18) and second (0.53 ± 0.14 vs. 0.44 ± 0.17) bout of exercise. There were negative correlations between I229/97 and rLBCL (ƍ = –0.37), and I229/97 and fMLP-LBCL (ƍ = –0.40) – analysis of pooled pre- and post-exercise data (n = 66). cf mt- DNA integrity (I218/78) did not alter in response to exercise. This suggests an involvement of phagocyte ROS in cf n-DNA strand breaks in response to exhaustive exercise.

The work carried out by the University of Catania is in the framework of the project "Safe and Smart Farming with Artificial Intelligence and Robotics-programma ricerca di ateneo UNICT 2020-22 linea 2" ABSTRACT Mobile robotic systems have evolved to include sensors capable of truthfully describing robot status and operating environment as accurately and reliably as never before. This possibility is challenged by effective sensor data exploitation, because of the cognitive load an operator is exposed to, due to the large amount of data and time-dependency constraints. This paper addresses this challenge in remote-vehicle teleoperation by proposing an intuitive way to present sensor data to users by means of using mixed reality and visual aids within the user interface. We propose a method for organizing information presentation and a set of visual aids to facilitate visual communication of data in teleoperation control panels. The resulting sensor-information presentation appears coherent and intuitive, making it easier for an operator to catch and comprehend information meaning. This increases situational awareness and speeds up decision-making. Our method is implemented on a real mobile robotic system operating outdoor equipped with on-board internal and external sensors, GPS, and a reconstructed 3D graphical model provided by an assistant drone. Experimentation verified feasibility while intuitive and comprehensive visual communication was confirmed through an assessment, which encourages further developments.