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1دورية أكاديمية
المؤلفون: Cristian Trâmbițaș, Bogdan Andrei Cordoș, Dorin Constantin Dorobanțu, Cristian Vintilă, Alexandru Petru Ion, Timea Pap, David Camelia, Claudiu Puiac, Emil Marian Arbănași, Claudiu Constantin Ciucanu, Adrian Vasile Mureșan, Eliza Mihaela Arbănași, Eliza Russu
المصدر: Bioengineering, Vol 11, Iss 2, p 184 (2024)
مصطلحات موضوعية: peripheral nerve injuries, peripheral nerve regeneration, 3D nerve guidance conduit, uniaxial, mechanical characteristics, stiffness, Technology, Biology (General), QH301-705.5
الوصف: Background: Peripheral nerve injuries (PNIs) represent a significant clinical problem, and standard approaches to nerve repair have limitations. Recent breakthroughs in 3D printing and stem cell technologies offer a promising solution for nerve regeneration. The main purpose of this study was to examine the biomechanical characteristics in muscle tissue distal to a nerve defect in a murine model of peripheral nerve regeneration from physiological stress to failure. Methods: In this experimental study, we enrolled 18 Wistar rats in which we created a 10 mm sciatic nerve defect. Furthermore, we divided them into three groups as follows: in Group 1, we used 3D nerve guidance conduits (NGCs) and adipose stem cells (ASCs) in seven rats; in Group 2, we used only 3D NGCs for seven rats; and in Group 3, we created only the defect in four rats. We monitored the degree of atrophy at 4, 8, and 12 weeks by measuring the diameter of the tibialis anterior (TA) muscle. At the end of 12 weeks, we took the TA muscle and analyzed it uniaxially at 10% stretch until failure. Results: In the group of animals with 3D NGCs and ASCs, we recorded the lowest degree of atrophy at 4 weeks, 8 weeks, and 12 weeks after nerve reconstruction. At 10% stretch, the control group had the highest Cauchy stress values compared to the 3D NGC group (0.164 MPa vs. 0.141 MPa, p = 0.007) and the 3D NGC + ASC group (0.164 MPa vs. 0.123 MPa, p = 0.007). In addition, we found that the control group (1.763 MPa) had the highest TA muscle stiffness, followed by the 3D NGC group (1.412 MPa), with the best muscle elasticity showing in the group in which we used 3D NGC + ASC (1.147 MPa). At failure, TA muscle samples from the 3D NGC + ASC group demonstrated better compliance and a higher degree of elasticity compared to the other two groups (p = 0.002 and p = 0.008). Conclusions: Our study demonstrates that the combination of 3D NGC and ASC increases the process of nerve regeneration and significantly improves the compliance and mechanical characteristics of muscle tissue distal to the injury site in a PNI murine model.
وصف الملف: electronic resource
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2دورية أكاديمية
المصدر: Bulletin of Medical Sciences ; volume 95, issue 1, page 78-88 ; ISSN 2537-5059
الوصف: Introduction: Diseases related to the elderly, including osteoporosis and the resulting fractures have a high incidence and are characterized by a high risk of early death. Most hip fractures are treated surgically. Its cost projections vary widely depending on the region, the level of institutional care, and the surgical solutions used. Material and method: We performed a retrospective study using hospital data from 2018-2019. The study included patients whose main diagnosis was: S72.0 - femoral neck fracture, S72.1 - pertrochanteric fracture, S72.2 - subtrochanteric fracture. We used hospital data from seven Romanian counties, Arad, Arges, Bucharest, Szilágy, Temes, Tulcea and Vaslui. Results: Women were significantly more affected (68.3%) than men, however the risk of mortality was 1.7 times higher among men. The average age was 77.2 years, 86% of the patients were over 65 years old. Most patients (69.3% ) were urban residents, but they were also characterized by a higher LOS and mortality. Discussion: Fracture types, gender distribution and correlation with urbanization of the fractures are consistent with international epidemiological data. Regression analysis shows a significant correlation between the length of hospital stay and the following variables: gender, environment, age, diagnosis, type of hospital and death. Regarding the average time of hospital stay, the shortest duration of hospitalization was in Vaslui and Tulcea (9.59 and 9.79 days), while the longest (13.42 and 14.61 days) were in Arad and Arges counties. Conclusions: On average, the patient hospitalization time in the examined counties is higher (13 days) than the Romanian average (11 days). Mortality is significantly higher among men, urban residents and those who suffer subtrochanteric fractures. Regarding the costs per patient of fractures, it can be said that Arad is the most economical, while Salaj county is the least cost-effective.
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المؤلفون: Timea Pap, Paul Serban Agachi, Ancuţa Roxana Trifoi
المصدر: Renewable and Sustainable Energy Reviews. 62:804-814
مصطلحات موضوعية: Biodiesel, 010405 organic chemistry, Renewable Energy, Sustainability and the Environment, Acetal, food and beverages, 010402 general chemistry, Reactor design, 01 natural sciences, 0104 chemical sciences, Catalysis, Diesel fuel, chemistry.chemical_compound, chemistry, Glycerol, Organic chemistry, Reaction system
الوصف: With the rapid development of the biodiesel industry all over the world, a large surplus of glycerol has been created, so economic uses of glycerol for value-added products are critical for the sustainability of the biodiesel industry. One of the main interests in recent years for glycerin utilization is its conversion in acetals and ketals, with the potential to be used as fuel additives. Glycerol acetals and ketals can be synthesized through the acid-catalyzed reaction of glycerol with aldehydes and ketones, respectively. This paper reviews different approaches and techniques used to obtain glycerol acetals and ketals, regarding the reactor design, catalyst design and the effect of different parameters in the reaction system.
الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::dd254ee29f0db85b46f091f84c49c83bTest
https://doi.org/10.1016/j.rser.2016.05.013Test
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