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2.
Giuseppe Placidi Danilo Avola Marco Ferrari Daniela Iacoviello Andrea Petracca Valentina Quaresima Matteo Spezialetti 《Computer methods and programs in biomedicine》2014
Background and objective
The degeneration of the balance control system in the elderly and in many pathologies requires measuring the equilibrium conditions very often. In clinical practice, equilibrium control is commonly evaluated by using a force platform (stabilometric platform) in a clinical environment.In this paper, we demonstrate how a simple movement analysis system, based on a 3D video camera and a 3D real time model reconstruction of the human body, can be used to collect information usually recorded by a physical stabilometric platform.Methods
The algorithm used to reconstruct the human body model as a set of spheres is described and discussed. Moreover, experimental measurements and comparisons with data collected by a physical stabilometric platform are also reported. The measurements were collected on a set of 6 healthy subjects to whom a change in equilibrium condition was stimulated by performing an equilibrium task.Results
The experimental results showed that more than 95% of data collected by the proposed method were not significantly different from those collected by the classic platform, thus confirming the usefulness of the proposed system.Conclusions
The proposed virtual balance assessment system can be implemented at low cost (about 500$) and, for this reason, can be considered a home use medical device. On the contrary, astabilometric platform has a cost of about 10,000$ and requires periodical calibration. The proposed system does not require periodical calibration, as is necessary for stabilometric force platforms, and it is easy to use. In future, the proposed system with little integration can be used, besides being an emulator of a stabilometric platform, also to recognize and track, in real time, head, legs, arms and trunk, that is to collect information actually obtained by sophisticated optoelectronic systems. 相似文献3.
Mario Kurtjak Marija Vukomanović Lovro Kramer Danilo Suvorov 《Journal of materials science. Materials in medicine》2016,27(11):170
Intensive research in the area of medical nanotechnology, especially to cope with the bacterial resistance against conventional antibiotics, has shown strong antimicrobial action of metallic and metal-oxide nanomaterials towards a wide variety of bacteria. However, the important remaining problem is that nanomaterials with highest antibacterial activity generally express also a high level of cytotoxicity for mammalian cells. Here we present gallium nanoparticles as a new solution to this problem. We developed a nanocomposite from bioactive hydroxyapatite nanorods (84?wt %) and antibacterial nanospheres of elemental gallium (16?wt %) with mode diameter of 22?±?11?nm. In direct comparison, such nanocomposite with gallium nanoparticles exhibited better antibacterial properties against Pseudomonas aeruginosa and lower in-vitro cytotoxicity for human lung fibroblasts IMR-90 and mouse fibroblasts L929 (efficient antibacterial action and low toxicity from 0.1 to 1?g/L) than the nanocomposite of hydroxyapatite and silver nanoparticles (efficient antibacterial action and low toxicity from 0.2 to 0.25?g/L). This is the first report of a biomaterial composite with gallium nanoparticles. The observed strong antibacterial properties and low cytotoxicity make the investigated material promising for the prevention of implantation–induced infections that are frequently caused by P. aeruginosa. 相似文献
4.
Bytecode instrumentation is a widely used technique to implement aspect weaving and dynamic analyses in virtual machines such as the Java virtual machine. Aspect weavers and other instrumentations are usually developed independently and combining them often requires significant engineering effort, if at all possible. In this article, we present polymorphic bytecode instrumentation(PBI), a simple but effective technique that allows dynamic dispatch amongst several, possibly independent instrumentations. PBI enables complete bytecode coverage, that is, any method with a bytecode representation can be instrumented. We illustrate further benefits of PBI with three case studies. First, we describe how PBI can be used to implement a comprehensive profiler of inter‐procedural and intra‐procedural control flow. Second, we provide an implementation of execution levels for AspectJ, which avoids infinite regression and unwanted interference between aspects. Third, we present a framework for adaptive dynamic analysis, where the analysis to be performed can be changed at runtime by the user. We assess the overhead introduced by PBI and provide thorough performance evaluations of PBI in all three case studies. We show that pure Java profilers like JP2 can, thanks to PBI, produce accurate execution profiles by covering all code, including the core Java libraries. We then demonstrate that PBI‐based execution levels are much faster than control flow pointcuts to avoid interference between aspects and that their efficient integration in a practical aspect language is possible. Finally, we report that PBI enables adaptive dynamic analysis tools that are more reactive to user inputs than existing tools that rely on dynamic aspect‐oriented programming with runtime weaving. These experiments position PBI as a widely applicable and practical approach for combining bytecode instrumentations. © 2015 The Authors. Software: Practice and Experience Published by John Wiley & Sons Ltd. 相似文献
5.
Placidi G Franchi D Marsili L Gallo P 《Computer methods and programs in biomedicine》2007,88(2):144-151
Vascular catheterization is a common procedure in clinical medicine. It is normally performed by a specialist using an X-ray fluoroscopic guide and contrast-media. In the present paper, an image-guided navigation system which indicates a path providing guidance to the desired target inside the vascular tree is described with the aim of reducing the exposure of personnel and patients to X-rays during the catheterization procedure. A 3D model of the patient vascular tree, reconstructed with data collected by an angiography before starting the intervention, is used as a guide map instead of fluoroscopic scans. An accurate spatial correspondence between the body of the patient and the 3D reconstructed vascular model is established and, by means of a position indicator installed over the catheter tip, the real-time position/orientation of the tip is indicated correctly. This paper describes the system and the operational procedures necessary to use the proposed method efficiently during a catheter intervention. Preliminary experimental results on a phantom are also reported. 相似文献
6.
M Hara YM Liu L Zhen IS Cohen H Yu P Danilo K Ogino JP Bilezikian MR Rosen 《Canadian Metallurgical Quarterly》1997,96(10):3704-3709
BACKGROUND: The classic calciotropic hormone parathyroid hormone (PTH) and its paracrine factor parathyroid hormone-related protein (PTHrP) both increase heart rate. METHODS AND RESULTS: We used standard electrophysiological techniques to study the effects of PTH and PTHrP on isolated rabbit sinus node, isolated canine Purkinje fibers, and disaggregated rabbit sinus node myocytes. Sinus node maximum diastolic potential, activation voltage, and amplitude were unchanged by PTH or PTHrP (P>.05). However, the slope of phase 4 and the automatic rate were increased at PTH and PTHrP > or = 10 nmol/L (P<.05). Comparable results were seen in canine Purkinje fibers. We then used the perforated-patch technique to study the I(f) pacemaker current in sinus node. PTH 12.5 nmol/L and PTHrP 12.5 to 18 nmol/L increased I(f) at -65 mV by 68+/-41% (n=5) and 69+/-50% (n=5), respectively. Actions of both agents were reversible. The increase in I(f) appeared to result from a change in maximal conductance and not a shift in the voltage dependence of activation. CONCLUSIONS: These observations provide, for the first time, direct electrophysiological support for the chronotropic actions of PTH and PTHrP. They suggest that classic hormones and paracrine factors can have multiple functions and that in the case of PTH and PTHrP, a newly recognized action is to alter automaticity directly. 相似文献
7.
Danilo Predes Lorena A. Maia Isadora Matias Hannah Paola Mota Araujo Carolina Soares Fernanda G. Q. Barros-Arago Luiz F. S. Oliveira Renata R. Reis Nathalia G. Amado Alessandro B. C. Simas Fabio A. Mendes Flvia C. A. Gomes Claudia P. Figueiredo Jose G. Abreu 《International journal of molecular sciences》2022,23(20)
The Wnt/β-catenin signaling pathway dictates cell proliferation and differentiation during embryonic development and tissue homeostasis. Its deregulation is associated with many pathological conditions, including neurodegenerative disease, frequently downregulated. The lack of efficient treatment for these diseases, including Alzheimer’s disease (AD), makes Wnt signaling an attractive target for therapies. Interestingly, novel Wnt signaling activating compounds are less frequently described than inhibitors, turning the quest for novel positive modulators even more appealing. In that sense, natural compounds are an outstanding source of potential drug leads. Here, we combine different experimental models, cell-based approaches, neuronal culture assays, and rodent behavior tests with Xenopus laevis phenotypic analysis to characterize quercitrin, a natural compound, as a novel Wnt signaling potentiator. We find that quercitrin potentiates the signaling in a concentration-dependent manner and increases the occurrence of the Xenopus secondary axis phenotype mediated by Xwnt8 injection. Using a GSK3 biosensor, we describe that quercitrin impairs GSK3 activity and increases phosphorylated GSK3β S9 levels. Treatment with XAV939, an inhibitor downstream of GSK3, impairs the quercitrin-mediated effect. Next, we show that quercitrin potentiates the Wnt3a-synaptogenic effect in hippocampal neurons in culture, which is blocked by XAV939. Quercitrin treatment also rescues the hippocampal synapse loss induced by intracerebroventricular injection of amyloid-β oligomers (AβO) in mice. Finally, quercitrin rescues AβO-mediated memory impairment, which is prevented by XAV939. Thus, our study uncovers a novel function for quercitrin as a Wnt/β-catenin signaling potentiator, describes its mechanism of action, and opens new avenues for AD treatments. 相似文献
8.
Maria Infantino Aris Tsalouchos Edda Russo Selene Laudicina Valentina Grossi Barbara Lari Maurizio Benucci Lorenzo Stacchini Amedeo Amedei Patrizia Casprini Danilo Villalta Pietro Claudio Dattolo Mariangela Manfredi 《International journal of molecular sciences》2022,23(20)
The vulnerable population of kidney transplant recipients (KTRs) are low responders to COVID-19 vaccines, so specific immune surveillance is needed. The interferon-gamma (IFN-γ) release assay (IGRA) is effective in assessing T cell-mediated immunity. We assessed SARS-CoV-2-directed T cell responses in KTRs with absent antibody production after a third dose of the mRNA-1273 vaccine, using two different IGRAs. A cohort of 57 KTRs, who were actively followed up, received a third dose of the mRNA-1273 vaccine. After the evaluation of humoral immunity to SARS-CoV-2, 14 seronegative patients were tested with two commercial IGRAs (SD Biosensor and Euroimmun). Out of 14 patients, one and three samples were positive by IGRAs with Euroimmun and SD Biosensor, respectively. The overall agreement between the two assays was 85.7% (κ = 0.444). In addition, multivariate linear regression analysis showed no statistically significant association between the IFN-γ concentration, and the independent variables analyzed (age, gender, years since transplant, total lymphocytes cells/mcl, CD3+ cells/mcl, CD3+ CD4+ cells/mcl, CD3+ CD8+ cells/mcl, CD19+ cells/mcl, CD3-CD16+CD56+ cells/mcl) (p > 0.01). In a vulnerable setting, assessing cellular immune response to complement the humoral response may be advantageous. Since the two commercial IGRAs showed a good agreement on negative samples, the three discordant samples highlight the need for further investigations. 相似文献
9.
Salvatore Ulisse Enke Baldini Daniele Pironi Federica Gagliardi Domenico Tripodi Augusto Lauro Sabino Carbotta Danilo Tarroni Matteo DArmiento Aldo Morrone Flavio Forte Flaminia Frattaroli Severino Persechino Teresa Odorisio Vito DAndrea Eleonora Lori Salvatore Sorrenti 《International journal of molecular sciences》2022,23(17)
Clinical and epidemiological evidence indicate a relationship between thyroid diseases and melanoma. In particular, the hypothyroidism condition appears to promote melanoma spread, which suggests a protective role of thyroid hormones against disease progression. In addition, experimental data suggest that, in addition to thyroid hormones, other hormonal players of the hypothalamic–pituitary–thyroid (HPT) axis, namely the thyrotropin releasing hormone and the thyrotropin, are likely to affect melanoma cells behavior. This information warrants further clinical and experimental studies in order to build a precise pattern of action of the HPT hormones on melanoma cells. An improved knowledge of the involved molecular mechanism(s) could lead to a better and possibly personalized clinical management of these patients. 相似文献
10.
Barbara Peruzzi Enrica Urciuoli Michela Mariani Laura Chioma Luigi Tomao Ilaria Montano Mattia Algeri Rosa Luciano Danilo Fintini Melania Manco 《International journal of molecular sciences》2023,24(1)
Excess body weight has been considered beneficial to bone health because of its anabolic effect on bone formation; however, this results in a poor quality bone structure. In this context, we evaluated the involvement of circulating extracellular vesicles in the impairment of the bone phenotype associated with obesity. Circulating extracellular vesicles were collected from the plasma of participants with normal weight, as well as overweight and obese participants, quantified by flow cytometry analysis and used to treat mesenchymal stromal cells and osteoblasts to assess their effect on cell differentiation and activity. Children with obesity had the highest amount of circulating extracellular vesicles compared to controls. The treatment of mesenchymal stromal cells with extracellular vesicles from obese participants led to an adipogenic differentiation in comparison to vesicles from controls. Mature osteoblasts treated with extracellular vesicles from obese participants showed a reduction in differentiation markers in comparison to controls. Children with obesity who regularly performed physical exercise had a lower circulating extracellular vesicle amount in comparison to those with a sedentary lifestyle. This pilot study demonstrates how the high amount of circulating extracellular vesicles in children with obesity affects the bone phenotype and that physical activity can partially rescue this phenotype. 相似文献