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51.
In vitro development of engineered muscle using a scaffold based on the pressure‐activated microsyringe (PAM) technique
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Daniele Cei Adriana Malena Carmelo de Maria Emanuele Loro Federica Sandri Giulia del Moro Sara Bettio Lodovica Vergani Giovanni Vozzi 《Journal of tissue engineering and regenerative medicine》2017,11(1):138-152
The development of new human skeletal muscle tissue is an alternative approach to the replacement of tissue after severe damage, for example in the case of traumatic injury, where surgical reconstruction is often needed following major loss of natural tissue. Treatment to date has involved the transfer of muscle tissue from other sites, resulting in a functional loss and volume deficiency of donor sites. Approaches that seek to eliminate these problems include the relatively new solution of skeletal muscle engineering. Here there are two main components to consider: (a) the cells with their regenerative potential; and (b) the polymeric structure onto which cells are seeded and where they must perform their activities. In this paper we describe well‐defined two‐ and three‐dimensional polymeric structures able to drive the myoblast process of adhesion, proliferation and differentiation. We examine a series of polymers and protein adhesions with which to functionalize the structures, and cell‐seeding methods, with a view to defining the optimal protocol for engineering skeletal muscle tissue. All polymer samples were tested for their mechanical and biological properties, to support the validity of our results in the real context of muscle tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Emanuele Chisari Steven Yacovelli Karan Goswami Noam Shohat Paul Woloszyn Javad Parvizi 《The Journal of arthroplasty》2021,36(8):2942-2945.e1
BackgroundA leukocyte esterase (LE) test is inexpensive and provides real-time information about patients suspected of periprosthetic joint infections (PJIs). The 2018 International Consensus Meeting (ICM) recommends it as a diagnostic tool with a 2+ cutoff. There is still a lack of data revealing LE utility versus the ICM 2018 criteria for PJI.MethodsThis is a retrospective study of patients who underwent revision total hip and total knee arthroplasty at a single institution between March 2009 and December 2019. All patients underwent joint aspiration before the arthrotomy, and the LE strip test was performed on aspirated joint fluid. PJI was defined using the 2018 ICM criteria.ResultsAs per the 2018 ICM criteria, 78 patients were diagnosed with chronic PJI and 181 were not infected. An LE test with a cutoff of 1+ had a sensitivity of 0.744, a specificity of 0.906, a positive predictive value of 0.773, an accuracy of 0.825 (95% confidence interval 0.772-0.878), and a negative predictive value of 0.891. The positive likelihood ratio (LR+) was 7.917. Using an LE cutoff of 2 + had a sensitivity of 0.513, a specificity of 1.000, and an accuracy of 0.756 (95% confidence interval—0.812).ConclusionLE is a rapid and inexpensive test which can be performed at the bedside. Its performance is valuable as per ICM criteria. Based on the findings of this study and the given cohort, we suggest using the cutoff of LE1+ (result = negative or trace) as a point of care test to exclude infection, whereas LE at 2 + threshold has near absolute specificity for the diagnosis. 相似文献
53.
Alison E. Murray Fabien Kenig Christian H. Fritsen Christopher P. McKay Kaelin M. Cawley Ross Edwards Emanuele Kuhn Diane M. McKnight Nathaniel E. Ostrom Vivian Peng Adrian Ponce John C. Priscu Vladimir Samarkin Ashley T. Townsend Protima Wagh Seth A. Young Pung To Yung Peter T. Doran 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(50):20626-20631
The permanent ice cover of Lake Vida (Antarctica) encapsulates an extreme cryogenic brine ecosystem (−13 °C; salinity, 200). This aphotic ecosystem is anoxic and consists of a slightly acidic (pH 6.2) sodium chloride-dominated brine. Expeditions in 2005 and 2010 were conducted to investigate the biogeochemistry of Lake Vida’s brine system. A phylogenetically diverse and metabolically active Bacteria dominated microbial assemblage was observed in the brine. These bacteria live under very high levels of reduced metals, ammonia, molecular hydrogen (H2), and dissolved organic carbon, as well as high concentrations of oxidized species of nitrogen (i.e., supersaturated nitrous oxide and ∼1 mmol⋅L−1 nitrate) and sulfur (as sulfate). The existence of this system, with active biota, and a suite of reduced as well as oxidized compounds, is unusual given the millennial scale of its isolation from external sources of energy. The geochemistry of the brine suggests that abiotic brine-rock reactions may occur in this system and that the rich sources of dissolved electron acceptors prevent sulfate reduction and methanogenesis from being energetically favorable. The discovery of this ecosystem and the in situ biotic and abiotic processes occurring at low temperature provides a tractable system to study habitability of isolated terrestrial cryoenvironments (e.g., permafrost cryopegs and subglacial ecosystems), and is a potential analog for habitats on other icy worlds where water-rock reactions may cooccur with saline deposits and subsurface oceans. 相似文献
54.
Emanuele Angelucci Valeria Santini Anna Angela Di Tucci Giulia Quaresmini Carlo Finelli Antonio Volpe Giovanni Quarta Flavia Rivellini Grazia Sanpaolo Daniela Cilloni Flavia Salvi Giovanni Caocci Alfredo Molteni Daniele Vallisa Maria Teresa Voso Susanna Fenu Lorenza Borin Giancarlo Latte Giuliana Alimena Sergio Storti Alfonso Piciocchi Paola Fazi Marco Vignetti Sante Tura 《European journal of haematology》2014,92(6):527-536
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57.
Atomic force microscopy for biomechanical and structural analysis of human dermis: A complementary tool for medical diagnosis and therapy monitoring
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Leonardo Peñuela Carola Negro Michela Massa Erica Repaci Emanuele Cozzani Aurora Parodi Silvia Scaglione Rodolfo Quarto Roberto Raiteri 《Experimental dermatology》2018,27(2):150-155
Skin mechanical properties are usually measured considering the entire skin thickness and very little is known about the mechanical behaviour of individual skin layers. We propose atomic force microscopy (AFM) as a tool to quantify nanoscale changes in the biomechanical properties and ultrastructure of human papillary dermis exposed to different mechanical and physical stimuli. Samples from 3 human skin biopsies were studied: one stretched by obesity, one subjected to a high level of sun exposure and normal skin as control. Slices of the papillary dermis layer were harvested at controlled depths from each skin biopsy and 25 μm2 areas of each slice were imaged and D‐periodicity of collagen fibres measured by AFM, together with their stiffness. Standard histological analysis was also carried out to correlate biochemical properties and their distribution with stiffness and topography. We obtained similar stiffness values between the sample affected by obesity and the control sample at any depth level into the dermis, while the sun‐exposed sample presented a significantly lower stiffness. Additionally, all samples presented an increase in the stiffness at higher depths into the papillary dermis layer. Collagen fibres close to the epidermis of sample affected either by obesity and sun exposure—the former even more than the latter—are thicker and present a larger D‐period than those in the control sample. Our results open the possibility to use structural and mechanical analysis based on AFM as a complementary tool for medical diagnosis and therapy monitoring. 相似文献
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Fabio Santanelli Marco Mazzocchi Luca Renzi Emanuele Cigna 《Journal of plastic surgery and hand surgery》2013,47(3):183-185
Based on the assumption that the umbilicus is a wound that has healed by second intention, we describe a method of reconstruction. The procedure consists of complete resection of the umbilical scar and its reconstruction by a linear incision at the site of the new umbilicus and inversion of the skin hedges, which are sutured to the linea alba leaving a 1 cm space between the skin borders to cause secondary wound healing. This procedure provides a natural-looking umbilicus. It is easy and quick to do, and can be used for reconstruction after abdominoplasty, excision of a naevus, or when the umbilicus has been removed during a previous xiphopubic incision. 相似文献