Long-term results 8 years after autologous osteochondral transplantation: 7 T gagCEST and sodium magnetic resonance imaging with morphological and clinical correlation

SummaryObjectiveTo correlate long-term clinical outcome and the results of morphological as well as advanced biochemical magnetic resonance imaging (MRI) techniques [T2-mapping, glycosaminoglycan chemical exchange saturation transfer (gagCEST), sodium-23-imaging] in patients after autologous osteochondral transplantation (AOT) in knee joints.MethodNine AOT patients (two female and seven male; median age, 49) had clinical [International Knee Documentation Committee (IKDC), modified Lysholm, visual analog scale (VAS)] and radiological long-term follow-up examinations at a median of 7.9 years (inter-quartile range, 7.7–8.2). Standard morphological MRI and T2-mapping of cartilage were performed on a 3 T MR unit. Biochemical imaging further included sodium-23-imaging and chemical exchange saturation transfer (CEST) imaging at 7 T. The Magnetic resonance Observation of CArtilage Repair Tissue (MOCART) score was used for quantitative assessment of morphological MRI.ResultsClinical outcome was good with a median modified Lysholm score of 90. Median VAS revealed 1.0 and median MOCART score 75 points. The difference between native and repair cartilage was statistically significant for all three biochemical imaging techniques. The strongest correlation was found between the results of the advanced biochemical imaging methods sodium-23 and CEST [ρ = 0.952, 95% confidence interval (CI): (0.753; 0.992)]. Comparing the results from morphological and biochemical imaging, a correlation was found between MOCART score and CEST ratio [ρ = −0.749, 95% CI: (−0.944; −0.169)]. Comparing the results from clinical scores with MRI, a correlation between modified Lysholm and T2-mapping [ρ = −0.667, 95% CI: (−0.992; −0.005)] was observed.ConclusionLong-term clinical outcome in patients 7.9 years after AOT was good, but did not correlate with morphological and biochemical imaging results except for T2-mapping

Optimization of lipase production by solid-state fermentation of olive pomace: from flask to laboratory-scale packed-bed bioreactor

Lipases are versatile catalysts with many applications and can be produced by solid-state fermentation (SSF) using agro-industrial wastes. The aim of this work was to maximize the production of Aspergillus ibericus lipase under SSF of olive pomace (OP) and wheat bran (WB), evaluating the effect on lipase production of C/N ratio, lipids, phenols, content of sugars of substrates and nitrogen source addition. Moreover, the implementation of the SSF process in a packed-bed bioreactor and the improvement of lipase extraction conditions were assessed. Low C/N ratios and high content of lipids led to maximum lipase production. Optimum SSF conditions were achieved with a C/N mass ratio of 25.2 and 10.2% (w/w) lipids in substrate, by the mixture of OP:WB (1:1) and supplemented with 1.33% (w/w) (NH4)2SO4. Studies in a packed-bed bioreactor showed that the lower aeration rates tested prevented substrate dehydration, improving lipase production. In this work, the important role of Triton X-100 on lipase extraction from the fermented solid substrate has been shown. A final lipase activity of 223 ± 5 U g1 (dry basis) was obtained after 7 days of fermentation.Felisbela Oliveira acknowledges the financial support from Fundação para a Ciência e Tecnologia (FCT) of Portugal through grant SFRH/BD/87953/2012. José Manuel Salgado was supported by grant CEB/N2020–INV/01/2016 from Project ‘‘BIOTECNORTE-Underpinning Biotechnology to foster the north of Portugal bioeconomy’’ (NORTE-01-0145-FEDER-000004). Luı ´s Abrunhosa was supported by grant UMINHO/BPD/51/2015 from project UID/BIO/04469/2013 financed by FCT/MEC (OE). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER006684) and BioTecNorte operation (NORTE-01-0145-FEDER000004) funded by the European Regional Development Fund under the scope of Norte2020–Programa Operacional Regional do Norte. Noelia Pérez-Rodríguez acknowledges the financial support of FPU fellowship from the Spanish Ministry of Education, Culture and Sports. The authors thank the Spanish Ministry of Economy and Competitiveness for the financial support of this work (Project CTQ2015-71436-C2-1-R), which has partial financial support from the FEDER funds of the European Union.info:eu-repo/semantics/publishedVersio

Valorisation of Biowastes for the Production of Green Materials Using Chemical Methods

With crude oil reserves dwindling, the hunt for a sustainable alternative feedstock for fuels and materials for our society continues to expand. The biorefinery concept has enjoyed both a surge in popularity and also vocal opposition to the idea of diverting food-grade land and crops for this purpose. The idea of using the inevitable wastes arising from biomass processing, particularly farming and food production, is, therefore, gaining more attention as the feedstock for the biorefinery. For the three main components of biomass—carbohydrates, lipids, and proteins—there are long-established processes for using some of these by-products. However, the recent advances in chemical technologies are expanding both the feedstocks available for processing and the products that be obtained. Herein, this review presents some of the more recent developments in processing these molecules for green materials, as well as case studies that bring these technologies and materials together into final products for applied usage

Sodium Magnetic Resonance Imaging of Ankle Joint in Cadaver Specimens, Volunteers, and Patients After Different Cartilage Repair Techniques at 7 T: Initial Results

Objectives: The goal of cartilage repair techniques such as microfracture (MFX) or matrix-associated autologous chondrocyte transplantation (MACT) is to produce repair tissue (RT) with sufficient glycosaminoglycan (GAG) content. Sodium magnetic resonance imaging (MRI) offers a direct and noninvasive evaluation of the GAG content in native cartilage and RT. In the femoral cartilage, this method was able to distinguish between RTs produced by MFX and MACT having different GAG contents. However, it needs to be clarified whether sodium MRI can be useful for evaluating RT in thin ankle cartilage. Thus, the aims of this 7-T study were (1) to validate our sodium MRI protocol in cadaver ankle samples, (2) to evaluate the sodium corrected signal intensities (cSI) in cartilage of volunteers, (3) and to compare sodium values in RT between patients after MFX and MACT treatment. Materials and Methods: Five human cadaver ankle samples as well as ankles of 9 asymptomatic volunteers, 6 MFX patients and 6 MACT patients were measured in this 7-T study. Sodium values from the ankle samples were compared with histochemically evaluated GAG content. In the volunteers, sodium cSI values were calculated in the cartilages of ankle and subtalar joint. In the patients, sodium cSI in RT and reference cartilage were measured, morphological appearance of RT was evaluated using the magnetic resonance observation of cartilage repair tissue (MOCART) scoring system, and clinical outcome before and after surgery was assessed using the American Orthopaedic Foot and Ankle Society score and Modified Cincinnati Knee Scale. All regions of interest were defined on morphological images and subsequently transferred to the corresponding sodium images. Analysis of variance, t tests, and Pearson correlation coefficients were evaluated. Results: In the patients, significantly lower sodium cSI values were found in RT than in reference cartilage for the MFX (P = 0.007) and MACT patients (P = 0.008). Sodium cSI and MOCART scores in RT did not differ between the MFX and MACT patients (P = 0.185). No significant difference in sodium cSI was found between reference cartilage of the volunteers and the patients (P = 0.355). The patients showed significantly higher American Orthopaedic Foot and Ankle Society and Modified Cincinnati scores after treatment than they did before treatment. In the volunteers, sodium cSI was significantly higher in the tibial cartilage than in the talar cartilage of ankle joint (P = 0.002) and in the talar cartilage than in the calcaneal cartilage of subtalar joint (P < 0.001). Data from the cadaver ankle samples showed a strong linear relationship between the sodium values and the histochemically determined GAG content (r = 0.800; P < 0.001; R2 = 0.639). Conclusions: This study demonstrates the feasibility of in vivo quantification of sodium cSI, which can be used for GAG content evaluation in thin cartilages of ankle and subtalar joints at 7 T. A strong correlation observed between the histochemically evaluated GAG content and the sodium values proved the sufficient sensitivity of sodium MRI to changes in the GAG content of cartilages in the ankle. Both MFX and MACT produced RT with lower sodium cSI and, thus, of lower quality compared with reference cartilage in the patients or in the volunteers. Our results suggest that MFX and MACT produce RT with similar GAG content and similar morphological appearance in patients with similar surgery outcome. Sodium MRI at 7 T allows a quantitative evaluation of RT quality in the ankle and may thus be useful in the noninvasive assessment of new cartilage repair procedures