231 research outputs found

    Detection of seven β2-agonists in teeth by LC-MS/MS: preliminary results.

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    β2-agonists are powerful tocolytic (the only use permitted in cattle) and bronchodilator agents, butmay also be administered as growth promoters to improve the production of lean meat increasing alsothe lipolytic activity. Although the European Union (EU), China and other Asian countries have bannedthe use of β2-agonists for growth promoting purposes (European Union, 2003), the United States ofAmerica (USA) authorised ractopamine as a feed additive for swine, cattle and turkey. These veterinarydrugs, generally show high clearance rates in the conventional biological matrices, as well as urine, liverand muscle, making difficult their detection (Wu, 2014). For this reason, we suggested bovine teeth asa new unconventional matrix of accumulation in a more long-time window, for the detection ofcimaterol, clenbuterol, isoxsuprine, mabuterol, ractopamine, salbutamol and terbutaline. In literature,the few studies on teeth are limited to human (Andra, 2015) and are absent for veterinary medicine.The samples extracted by a simple liquid extraction step with ethyl acetate:tert-butyl methyl ether (4:1,v/v) after washing and pulverization of teeth, through a ball mill, were analysed using a liquidchromatography tandem mass spectrometry (LC-MS/MS) confirmatory method validated according tothe Commission Decision 2002/657/EC criteria (European Union, 2002). Teeth from 8 veal calves,administered per os with 80 mg day-1 oral ractopamine for 32 days, and from seven random bovinesfrom the food chain were collected at the slaughterhouse to test the suitability of this matrix. Theresults demonstrated ractopamine presence in teeth from the treated animals (average concentration8.90 ng g-1). Isoxsuprine was found in a control sample (13.67 ng g-1), demonstrating the effectivenessof this matrix as a powerful tool to ensure illegal treatment

    Hybrid approach to thoracoabdominal aortic aneurysms in patients with prior aortic surgery

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    none7Objective: The hybrid approach to the repair of thoracoabdominal aortic aneurysm (TAAA), consisting of visceral aortic debranching with retrograde revascularization of the splanchnic and renal arteries and aneurysm exclusion using stent grafts, has been previously described and may be considered particularly appealing in high-risk patients, especially those who have undergone prior aortic surgery. This study analyzed prospectively recorded data of a series of high-risk patients with prior aortic surgery who underwent hybrid TAAA repair at our institute and contrasted the outcomes with those of a similar group of patients who underwent conventional open TAAA repair. Methods: Between 2001 and 2006, 13 patients (12 men) with a median age of 69.6 years (range, 35 to 82 years) underwent one-stage hybrid repair of TAAA (7 type I, 2 type II, 2 type IV, and 2 aneurysms of the visceral aortic patch). These patients, the hybrid group, had a history of aortic surgery (30.7% ascending, 30.7% descending, 46.1% abdominal aortic repair, and 15.4% redo TAAA) and were at high risk for open repair. The criteria used to define these patients as high risk and to indicate the need for hybrid treatment were American Society of Anesthesiologists (ASA) class 3 or 4 associated with a preoperative forced expiratory volume in 1 second (FEV1) <50%. In all cases, we accomplished partial or total visceral aortic debranching through (1) a previous visceral artery retrograde revascularization with synthetic grafts (single bypass, customized Y or bifurcated grafts), and (2) aortic endovascular repair with one of three different commercially produced stent grafts (Cook, W.L. Gore & Assoc, and Medtronic). We analyzed the results and compared the outcomes of the hybrid group with those of a similar group of 29 patients (25 men) with a median age 65.3 years (range, 58 to 79) selected from our overall series of 246 TAAA repairs between 1988 and 2005. These 29 patients, the conventionally treated group, were selected for having had aortic surgery (22% ascending, 38% descending, 42% abdominal aortic repair, and 10.3% redo TAAA), an ASA 3 or 4, a preoperative FEV1 <50%, and a conventional open repair of TAAA (10 type I, 5 type II, 4 type III, 7 type IV, and 3 aneurysms of the visceral aortic patch). Results: In the hybrid group, 32 visceral bypasses were completed and endovascular TAAA repair was successful in all cases. No intraoperative deaths occurred. Perioperative mortality was 23%, and morbidity was 30.8% (renal failure in 2, respiratory failure in 1, and delayed transient paraplegia in 1). At a median follow-up of 14.9 months (range, 11 days to 59.4 months), all grafts were patent at postoperative computed tomography angiography and no aneurysm-related deaths, endoleak, stent graft migration, or morbidity related to visceral revascularization had occurred. No conventionally treated patients died intraoperatively. Perioperative mortality was 17.2% and morbidity was 44.8% (respiratory failure in 7, coagulopathy in 1, renal failure in 2, and paraplegia in 3). At a median follow-up of 5.4 years (range, 1.7 to 7.9 years), no significant complications related to aortic repair occurred, except for three patients (10.3%) with asymptomatic dilatation of the visceral aortic patch <5 cm undergoing radiologic surveillance. Conclusion: Hybrid TAAA repair is technically feasible in selected cases. Perioperative morbidity and mortality were considerable in our subset of high-risk patients with prior aortic surgery, but no aneurysm-related or procedure-related complications were reported at mid-term follow-up. Hybrid TAAA repair did not lead to a significant improvement in outcomes compared with open TAAA repair in a similar group of patients. Larger series are required for valid statistical comparisons and longer follow-ups are necessary to evaluate the durability of hybrid repairs. © 2007 The Society for Vascular Surgery.Chiesa, R.; Tshomba, Y.; Melissano, G.; Marone, E.M.; Bertoglio, L.; Setacci, F.; Calliari, F.Chiesa, R.; Tshomba, Y.; Melissano, G.; Marone, ENRICO MARIA; Bertoglio, L.; Setacci, F.; Calliari, F

    Active space debris removal by a hybrid propulsion module

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    During the last 40 years, the mass of the artificial objects in orbit increased quite steadily at the rate of about 145 metric tons annually, leading to a total tally of approximately 7000 metric tons. Now, most of the cross-sectional area and mass (97% in LEO) is concentrated in about 4600 intact objects, i.e. abandoned spacecraft and rocket bodies, plus a further 1000 operational spacecraft. Simulations and parametric analyses have shown that the most efficient and effective way to prevent the outbreak of a long-term exponential growth of the catalogued debris population would be to remove enough cross-sectional area and mass from densely populated orbits. In practice, according to the most recent NASA results, the active yearly removal of approximately 0.1% of the abandoned intact objects would be sufficient to stabilize the catalogued debris in low Earth orbit, together with the worldwide adoption of mitigation measures. The candidate targets for removal would have typical masses between 500 and 1000 kg, in the case of spacecraft, and of more than 1000 kg, in the case of rocket upper stages. Current data suggest that optimal active debris removal missions should be carried out in a few critical altitude-inclination bands. This paper deals with the feasibility study of a mission in which the debris is removed by using a hybrid propulsion module as propulsion unit. Specifically, the engine is transferred from a servicing platform to the debris target by a robotic arm so to perform a controlled disposal. Hybrid rocket technology for de-orbiting applications is considered a valuable option due to high specific impulse, intrinsic safety, thrust throttle ability, low environmental impact and reduced operating costs. Typically, in hybrid rockets a gaseous or liquid oxidizer is injected into the combustion chamber along the axial direction to burn a solid fuel. However, the use of tangential injection on a solid grain Pancake Geometry allows for more compact design of the propulsion unit. Only explorative tests were performed in the past on this rocket configuration, which appears to be suitable as de-orbiting system of new satellites as well as for direct application on large debris in the framework of a mission for debris removal. The paper describes some critical aspects of the mission with particular concern to the target selection, the hybrid propulsion module, the operations as well as the systems needed to rendezvous and dock with the target, and the disposal strateg

    Active debris removal space mission concepts based on hybrid propulsion

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    During the last 40 years, the mass of the artificial objects in orbit increased quite steadily at the rate of about 145 metric tons annually, leading to a about 7000 metric tons. Most of the cross-sectional area and mass (97% in LEO) is concentrated in about 4500 intact abandoned objects plus a further 1000 operational spacecrafts. Analyses have shown that the most effective mitigation strategy should focus on the disposal of objects with larger cross-sectional area and mass from densely populated orbits. Recent NASA results have shown that worldwide adoption of mitigation measures in conjunction with active yearly removal of approximately 0.1% of the abandoned objects would stabilize the debris population. Targets would have typical masses between 500 and 1000 kg in the case of spacecraft, and of more than 1000 kg for rocket upper stages. In the case of Cosmos-3M 2nd stages, more than one object are located nearly in the same orbital plane. This provides the opportunity of multi-removal missions, more suitable for yearly removal rate and cost reduction needs. This paper identifies the requirements of two alternative space mission concepts for multiple active removal of large debris objects from LEO, as well as at investigating related technological and operational issues. The first concept relies on flying a multi-removal space platform carrying a number of Hybrid Engine Modules (HEMs) to dock with the pre-selected targets, according to a pre-fixed removal sequence. Each target is then de-orbited in a controlled way by firing the attached HEM package. Alternatively, the partial contribution of the atmospheric drag could be exploited to perform a cost-free altitude lowering. In this respect, the primary propulsion system of the multi-removal space platform could be used to leave the targeted debris into an orbit where the atmosphere effect is significant and a HEM could be attached on it for the atmospheric reentry. In such a way, thanks to the natural decay, the final burn for a controlled reentry will require less Delta-V. This second option introduces the question of in-orbit HEM aging, though a significant mass saving is expected, depending on mission details. With reference to the alternative mission concepts, particular attention will be given to multiple removal feasibility. These aspects will be investigated by using analytical models and numerical simulations. In addition, technological solutions relevant to mission and system aspects will be identified. Results will be used to compare the different mission concepts

    Fatty acid composition of lamb meat from Italian and German local breeds

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    The aim of this study was to evaluate and compare the quality characteristics, chemical composition and lipid profile of lamb meat from Italian (Biellese and Sambucana) and German (Texel-Merino-Blackhead-Charollais [TMBC]) breeds reared in extensive and semi-extensive production systems. Meat samples from 89 animals were analysed. The meat of the lambs from semi-intensively reared Biellese, and extensively reared Sambucana and TMBC breeds produced lean meat, with slightly higher intramuscular fat content in TMBC. The latter also produced meat of darker colour (P lt 0.05) and higher protein content (P lt 0.05). The meat of Sambucana lambs presented the lowest total cholesterol content (P lt 0.05). The fatty acid profile of the meat showed a clear advantage of both extensively reared breeds, which had substantially lower proportion of saturated but higher of polyunsaturated fatty acids, particularly n-3 (P lt 0.05). The beneficial effect of the extensive rearing conditions was associated with lower n-6/n3 ratio, and atherogenic and thrombogenic indices, thereby suggesting that production system can be used successfully to modify the fatty acid profile to achieve a positive effect for the human health.The authors are grateful to EU ERA-NET programme and the Portuguese Foundation for Science and Technology (FCT) for funding the project “EcoLamb–Holistic Production to Reduce the Ecological Footprint of Meat (SusAn/0002/2016). CIMO authors are grateful to FCT and FEDER under Programme PT2020 for financial support to CIMO (UIDB/00690/2020). Dr. Gonzales-Barron acknowledges the national funding by FCT, P.I., through the Institutional Scientific Employment Programme contract. Jos´e M. Lorenzo is member of the HealthyMeat network, funded by CYTED (ref. 119RT0568).info:eu-repo/semantics/publishedVersio

    Fenestrated and Branched Endografts for Post-Dissection Thoraco-Abdominal Aneurysms: Results of a National Multicentre Study and Literature Review

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    Objective: Fenestrated and branched endografting (F/B-EVAR) has been proposed as an endovascular solution for chronic post-dissection thoraco-abdominal aneurysms (PD-TAAAs). The aim of this study was to analyse the experience of four high volume centres nationwide and the current available literature. Methods: Data on patients undergoing F/B-EVAR in four Italian academic centres between 2008 and 2019 were collected, and those from patients with PD-TAAAs were analysed retrospectively. Peri-operative morbidity and mortality were assessed as early outcomes. Survival, freedom from re-intervention (FFR), target visceral vessel (TVV) patency, and aortic remodelling were assessed as follow up outcomes. A MEDLINE search was performed for studies published from 2008 to 2020 reporting on F/B-EVAR in PD-TAAAs. Results: Among 351 patients who underwent F/B-EVAR for TAAAs, 37 (11%) had PD-TAAAs (Crawford's extent I–III: 35% – 95%). Overall, 135 TVVs (from true lumen 120; false lumen seven; both true and false lumen eight) were accommodated by fenestrations (96% – 71%) and branches (39% – 29%). Technical success (TS) was achieved in 34 (92%) cases with three failures due to endoleaks (Ia: 1; Ic: 1; III: 1). There were no 30 day deaths. No cases of permanent spinal cord ischaemia (SCI) were recorded and six (16%) patients suffered from transient deficits. Renal function worsening (eGFR < 30% than baseline) and pulmonary complications were reported in two (5%) and four (11%) cases, respectively. From the Kaplan–Meier analysis, three year survival, FFR, and TVV patency were 81%, 66%, and 97%, respectively. Radiological imaging was available for 30 (81%) patients at 12 months with complete false lumen thrombosis in 26 (87%). Two hundred and fifty-six patients were reported in seven published papers with TS, 30 day mortality, and SCI ranging from 99% to 100%, 0 to 6%, and 0 to 16%, respectively. The mean follow up ranged from 12 to 26 months, with estimated two year survival between 81% and 90% and a re-intervention rate between 19% and 53%. Conclusion: F/B-EVAR is effective to treat PD-TAAAs. A high re-intervention rate is necessary to complete the aneurysm exclusion and promote aortic remodelling successfully

    RANK-Dependent Autosomal Recessive Osteopetrosis: Characterization of Five New Cases With Novel Mutations

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    Autosomal recessive osteopetrosis (ARO) is a genetically heterogeneous disorder attributed to reduced bone resorption by osteoclasts. Most human AROs are classified as osteoclast rich, but recently two subsets of osteoclast-poor ARO have been recognized as caused by defects in either TNFSF11 or TNFRSF11A genes, coding the RANKL and RANK proteins, respectively. The RANKL/RANK axis drives osteoclast differentiation and also plays a role in the immune system. In fact, we have recently reported that mutations in the TNFRSF11A gene lead to osteoclast-poor osteopetrosis associated with hypogammaglobulinemia. Here we present the characterization of five additional unpublished patients from four unrelated families in which we found five novel mutations in the TNFRSF11A gene, including two missense and two nonsense mutations and a single-nucleotide insertion. Immunological investigation in three of them showed that the previously described defect in the B cell compartment was present only in some patients and that its severity seemed to increase with age and the progression of the disease. HSCT performed in all five patients almost completely cured the disease even when carried out in late infancy. Hypercalcemia was the most important posttransplant complication. Overall, our results further underline the heterogeneity of human ARO also deriving from the interplay between bone and the immune system, and highlight the prognostic and therapeutic implications of the molecular diagnosis. © 2012 American Society for Bone and Mineral Researc

    Magnetic Properties of Monomer and Dimer Tetrahedral VOx Entities Dispersed on Amorphous Silica-based Materials: Prediction of EPR Parameters from Relativistic DFT Calculations and Broken Symmetry Approach to Exchange Couplings

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    Molecular structures of the isolated tetrahedral oxovanadium(IV) and bridged μ-oxo-divanadium(IV) complexes hosted by the clusters mimicking surfaces of amorphous silica-based materials were investigated using density functional theory (DFT) calculations. Principal values of the g and A tensors for the monomer vanadyl species were obtained using the coupled-perturbed DFT level of theory and the spin–orbit mean-field approximation (SOMF). Magnetic exchange interaction for the μ-oxo bridged vanadium(IV) dimer was investigated within the broken symmetry approach. An antiferromagnetic coupling of the individual magnetic moments of the vanadium(IV) centers in the [VO–O–VO]2+ bridges was revealed and discussed in detail. The coupling explains pronounced decrease of the electron paramagnetic resonance signal (EPR) intensity, observed for the reduced VOx/SiO2 samples with the increasing coverage of vanadia, in terms of transformation of the paramagnetic monomer species into the dimers with S = 0 ground state
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