1,017 research outputs found

    Assessing the mechanical weakness of vertebrae affected by primary tumors : a feasibility study

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    Patients spend months between the primary spinal tumor diagnosis and the surgical treatment, due to the need for performing chemotherapy and/or radiotherapy. During this period, they are exposed to an unknown risk of fracture. The aim of this study was to assess if it is possible to measure the mechanical strain in vertebrae affected by primary tumors, so as to open the way to an evidence-based scoring or prediction tool. We performed biomechanical tests on three vertebrae with bone tumor removed from patients. The tests were designed so as not to compromise the standard surgical and diagnostic procedures. Non-destructive mechanical tests in combination with state-of-the-art digital image correlation allowed to measure the distribution of strain on the surface of the vertebra. Our study has shown that the strains in the tumor region is circa 3 times higher than in the healthy bones, with principal strain peaks of 40,000/−20,000 microstrain, indicating a stress concentration potentially triggering vertebral fracture. This study has proven it is possible to analyze the mechanical behavior of primary tumor vertebrae as part of the clinical treatment protocol. This will allow building a tool for quantifying the risk of fracture and improving decision making in spine tumors

    The c4 atriplex halimus vs. The c3 atriplex hortensis: Similarities and differences in the salinity stress response

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    open7noSoil properties and the ability to sustain agricultural production are seriously impaired by salinity. The cultivation of halophytes is seen as a solution to cope with the problem. In this framework, a greenhouse pot experiment was set up to assess salinity response in the perennial C4 species Atriplex halimus, and in the following three cultivars of the annual C3 Atriplex hortensis: green, red, and scarlet. The four genotypes were grown for 35 days with water salinity (WS) ranging from 0 to 360 mM NaCl. Plant height and fresh weight (FW) increased at 360 vs. 0 WS. The stomatal conductance (GS) and transpiration rate (E) were more severely affected by salinity in the C4 A. halimus than in the C3 species A. hortensis. This was reflected in a lower leaf water potential indicating stronger osmotic adjustment, and a higher relative water content associated with more turgid leaves, in A. halimus than A. hortensis. In a PCA including all the studied traits, the GS and E negatively correlated to the FW, which, in turn, positively correlated with Na concentration and intrinsic water use efficiency (iWUE), indicating that reduced gas exchange associated with Na accumulation contributed to sustain iWUE under salinity. Finally, FTIR spectroscopy showed a reduced amount of pectin, lignin, and cellulose under salinity, indicating a weakened cell wall structure. Overall, both species were remarkably adapted to salinity: From an agronomic perspective, the opposite strategies of longer vs. faster soil coverage, involved by the perennial A. halimus vs. the annual A. hortensis cv. scarlet, are viable natural remedies for revegetating marginal saline soils and increasing soil organic carbon.openCalone R.; Cellini A.; Manfrini L.; Lambertini C.; Gioacchini P.; Simoni A.; Barbanti L.Calone R.; Cellini A.; Manfrini L.; Lambertini C.; Gioacchini P.; Simoni A.; Barbanti L

    Management Zones Delineation through Clustering Techniques Based on Soils Traits, NDVI Data, and Multiple Year Crop Yields

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    Availability of georeferenced yield data involving different crops over years, and their use in future crop management, are a subject of growing debate. In a 9 hectare field in Northern Italy, seven years of yield data, including wheat (3 years), maize for biomass (2 years), sunflower, and sorghum, and comprising remote (Landsat) normalized difference vegetation index (NDVI) data during central crop stages, and soil analysis (grid sampling), were subjected to geostatistical analysis (semi-variogram fitting), spatial mapping (simple kriging), and Pearson’s correlation of interpolated data at the same resolution (30 m) as actual NDVI values. Management Zone Analyst software indicated two management zones as the optimum zone number in multiple (7 year) standardized yield data. Three soil traits (clay content, total limestone, total nitrogen) and five dates within the NDVI dataset (acquired in different years) were shown to be best correlated with multiple-and single-year yield data, respectively. These eight parameters were normalized and combined into a two-zone multiple soil and NDVI map to be compared with the two-zone multiple yield map. This resulted in 83% pixel agreement in the high and low zone (89 and 10 respective pixels in the soil and NDVI map; 73 and 26 respective pixels in the yield map) between the two maps. The good agreement, which is due to data buffering across different years and crop types, is a good premise for differential management of the soil-and NDVI-based two zones in future cropping seasons

    Comparison of physical, microstructural, antioxidant and enzymatic properties of pineapple cubes treated with conventional heating, ohmic heating and high-pressure processing

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    Pineapple cubes in sugar syrup were treated with high-pressure processing (HPP), conventional (DIM) heating and ohmic heating (OHM). Samples were compared in terms of microstructural, physical (total soluble solids, sieve analysis, texture and colour) and residual pectin methylesterase activity (PME) and total antioxidant capacity. OHM yielded relevant changes in cellular microstructure and electroporation of the cell wall. The HPP treatment favoured the presence of soluble solids in the syrup, and the samples were less damaged in terms of shape and microstructure. in the samples were harder following HPP than they were with OHM and DIM, while HPP showed the highest colorimetric (ΔE) differences compared with RAW samples. The PME residual activity was the lowest in pineapple treated by DIM, while the antioxidant capacity was comparable among treated samples

    Description of the relationship between NOHL classification in drug-induced sleep endoscopy and initial AHI in patients with moderate to severe OSAS, and evaluation of the results obtained with oral appliance therapy

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    Descrizione della relazione tra Classificazione NOHL definita durante la Drug-Induced Sleep Endoscopy e AHI iniziale in pazienti con OSAS da moderato a grave, e valutazione dei risultati ottenuti con dispositivi orali

    Muscle power in basketball and volleyball players: relationship between isokinetic dynamometry and vertical jump

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    The aims of this study were: 1) to determine the anthropometric characteristics and body compositon of players; 2) to evaluate the maximal muscle power of the knee extensors muscles with the isokinetic dynamometry; 3) to determine the relationships between the test of isokinetic power and the vertical jum p test; 4) to compare the results between sports. A sample of 12 basketball players and 13 volleyball players was evaluated in several anthropometric measures and in two tests of muscle power. Body composition was determined through the equation by Jackson & Pollock (1978). Vertical jum p test was made without the arm movements, and the isokinetic muscle power test of the knee extensors was made in four speeds: 60, 180, 240 and 300°/sec.The results showed that the basketball players were taller, heavier and fatter than the volleyball players. There were no significant diferences in power output. When power was related to body weight, volleyball players showed higher values in the vertical jum p test and the isokinetic power test at 60°/sec. and in the vertical jump test when corrected by lean body mass. Relationships between maximal power tests showed from moderate to high degree between isokinetic power test at 180 and 300°/sec. and the vertical jum p test for basketball players. Volleyball players showed similar results at 180 and 300°/sec. Similar results were found when tests were corrected for body weight and lean body mass for basketball players, but in volleyball players relationships were from low to moderateOs objetivos do estudo foram: 1) determinar as características antropométricas e a composição corporal dos jogadores, 2) avaliar a potência máxima dos músculos extensores do joelho com a dinamometria isocinética, 3) verificar a relação entre o teste isocinético e o teste de salto vertical e 4) comparar os dois grupos de jogadores. Uma amostra de 12 jogadores de basquetebol e 13 de voleibol foi submetida a uma avaliação antropométrica e dois testes de potência muscular. A composição corporal foi calculada a partir da equação de Jackson & Pollock (1978). O teste de salto vertical foi realizado sem o auxílio dos membros superiores e a dinamometria isocinética executada no movimento de extensão do joelho às velocidades de 60, 180, 240 e 300°/seg. Nos jogadores de basquetebol foram encontrados valores mais altos para estatura peso e quantidade de gordura comparados com os voleibolistas. Os dois grupos apresentaram desempenho neuromuscular semelhante em termos absolutos. Relativo ao peso corporal os voleibolistas foram superiores no salto vertical e na potência à 60°/seg. e também no salto vertical relativo à massa magra. Na relação entre os dois testes em termos absolutos, correlações moderadas para altas foram encontradas à 180 e 300°/seg. para os jogadores de basquete e 180 e 240°/seg. para os de voleibol. Resultados semelhantes ocorreram nos praticantes de basquetebol relativo ao peso corporal e a massa magra, contudo, para os voleibolistas as relações foram de baixas para moderada

    Practical and clinical utility of non-invasive vagus nerve stimulation (nVNS) for the acute treatment of migraine. A post hoc analysis of the randomized, sham-controlled, double-blind PRESTO trial

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    Background: The PRESTO study of non-invasive vagus nerve stimulation (nVNS; gammaCore®) featured key primary and secondary end points recommended by the International Headache Society to provide Class I evidence that for patients with an episodic migraine, nVNS significantly increases the probability of having mild pain or being pain-free 2 h post stimulation. Here, we examined additional data from PRESTO to provide further insights into the practical utility of nVNS by evaluating its ability to consistently deliver clinically meaningful improvements in pain intensity while reducing the need for rescue medication. Methods: Patients recorded pain intensity for treated migraine attacks on a 4-point scale. Data were examined to compare nVNS and sham with regard to the percentage of patients who benefited by at least 1 point in pain intensity. We also assessed the percentage of attacks that required rescue medication and pain-free rates stratified by pain intensity at treatment initiation. Results: A significantly higher percentage of patients who used acute nVNS treatment (n = 120) vs sham (n = 123) reported a ≥ 1-point decrease in pain intensity at 30 min (nVNS, 32.2%; sham, 18.5%; P = 0.020), 60 min (nVNS, 38.8%; sham, 24.0%; P = 0.017), and 120 min (nVNS, 46.8%; sham, 26.2%; P = 0.002) after the first attack. Similar significant results were seen when assessing the benefit in all attacks. The proportion of patients who did not require rescue medication was significantly higher with nVNS than with sham for the first attack (nVNS, 59.3%; sham, 41.9%; P = 0.013) and all attacks (nVNS, 52.3%; sham, 37.3%; P = 0.008). When initial pain intensity was mild, the percentage of patients with no pain after treatment was significantly higher with nVNS than with sham at 60 min (all attacks: nVNS, 37.0%; sham, 21.2%; P = 0.025) and 120 min (first attack: nVNS, 50.0%; sham, 25.0%; P = 0.018; all attacks: nVNS, 46.7%; sham, 30.1%; P = 0.037). Conclusions: This post hoc analysis demonstrated that acute nVNS treatment quickly and consistently reduced pain intensity while decreasing rescue medication use. These clinical benefits provide guidance in the optimal use of nVNS in everyday practice, which can potentially reduce use of acute pharmacologic medications and their associated adverse events. Trial registration: ClinicalTrials.gov identifier: NCT02686034

    Tantalum nanoparticles enhance the osteoinductivity of multiscale composites based on poly(lactide-co-glycolide) electrospun fibers embedded in a gelatin hydrogel

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    Bioresorbable polymeric materials have risen great interest as implants for bone tissue regeneration, since they show substantial advantages with respect to conventional metal devices, including biodegradability, flexibility, and the possibility to be easily modified to introduce specific functionalities. In the present work, an innovative nanocomposite scaffold, properly designed to show biomimetic and osteoinductive properties for potential application in bone tissue engineering, was developed. The scaffold is characterized by a multi-layer structure, completely different with respect to the so far employed polymeric implants, consisting in a poly(D,L-lactide-co-glycolide)/polyethylene glycol electrospun nanofibrous mat sandwiched between two hydrogel gelatin layers enriched with tantalum nanoparticles (NPs). The composition of the electrospun fibers, containing 10 wt% of polyethylene glycol, was selected to ensure a proper integration of the fibers in the gel phase, essential to endow the composite with flexibility and to prevent delamination between the layers. The scaffold maintained its structural integrity after six weeks of soaking in physiological solutions, albeit the gelatin phase was partially released. The combined use of gelatin, bioresorbable electrospun fibers and tantalum NPs endows the final device with biomimetic and osteoinductive properties. Indeed, results of the in vitro tests demonstrate that the obtained scaffolds clearly represent a favorable milieu for normal human bone-marrow derived mesenchymal stem cells viability and osteoblastic differentiation; moreover, inclusion of tantalum NPs in the scaffold improves cell performance with particular regard to early and late markers of osteoblastic differentiation. (C) 2022 Elsevier Ltd. All rights reserved

    Melatonin Induced Cold Tolerance in Plants: Physiological and Molecular Responses

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    Cold stress is one of the most limiting factors for plant growth and development. Cold stress adversely affects plant physiology, molecular and biochemical processes by determining oxidative stress, poor nutrient and water uptake, disorganization of cellular membranes and reduced photosynthetic efficiency. Therefore, to recover impaired plant functions under cold stress, the application of bio-stimulants can be considered a suitable approach. Melatonin (MT) is a critical bio-stimulant that has often shown to enhance plant performance under cold stress. Melatonin application improved plant growth and tolerance to cold stress by maintaining membrane integrity, plant water content, stomatal opening, photosynthetic efficiency, nutrient and water uptake, redox homeostasis, accumulation of osmolytes, hormones and secondary metabolites, and the scavenging of reactive oxygen species (ROS) through improved antioxidant activities and increase in expression of stress-responsive genes. Thus, it is essential to understand the mechanisms of MT induced cold tolerance and identify the diverse research gaps necessitating to be addressed in future research programs. This review discusses MT involvement in the control of various physiological and molecular responses for inducing cold tolerance. We also shed light on engineering MT biosynthesis for improving the cold tolerance in plants. Moreover, we highlighted areas where future research is needed to make MT a vital antioxidant conferring cold tolerance to plants
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