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991.
Robert Khnke Marcus Oliver Ahlers Moritz Alexander Birkelbach Florian Ewald Michael Krueger Imke Fiedler Bjrn Busse Max Heiland Tobias Vollkommer Martin Gosau Ralf Smeets Rico Rutkowski 《International journal of molecular sciences》2021,22(1)
Temporomandibular joint osteoarthritis (TMJ-OA) is a chronic degenerative disease that is often characterized by progressive impairment of the temporomandibular functional unit. The aim of this randomized controlled animal trial was a comparative analysis regarding the chondroregenerative potency of intra-articular stem/stromal cell therapy. Four weeks after combined mechanical and biochemical osteoarthritis induction in 28 rabbits, therapy was initiated by a single intra-articular injection, randomized into the following groups: Group 1: AB Serum (ABS); Group 2: Hyaluronic acid (HA); Group 3: Mesenchymal stromal cells (STx.); Group 4: Mesenchymal stromal cells in hyaluronic acid (HA + STx.). After another 4 weeks, the animals were euthanized, followed by histological examination of the removed joints. The histological analysis showed a significant increase in cartilage thickness in the stromal cell treated groups (HA + STx. vs. ABS, p = 0.028; HA + ST.x vs. HA, p = 0.042; STx. vs. ABS, p = 0.036). Scanning electron microscopy detected a similar heterogeneity of mineralization and tissue porosity in the subchondral zone in all groups. The single intra-articular injection of a stem cell containing, GMP-compliant advanced therapy medicinal product for the treatment of iatrogen induced osteoarthritis of the temporomandibular joint shows a chondroregenerative effect. 相似文献
992.
Aspects of high hydrostatic pressure food processing: Perspectives on technology and food safety 总被引:1,自引:0,他引:1
Kemal Aganovic Christian Hertel Rudi. F. Vogel Reimar Johne Oliver Schlüter Uwe Schwarzenbolz Henry Jäger Thomas Holzhauser Johannes Bergmair Angelika Roth Robert Sevenich Niels Bandick Sabine E. Kulling Dietrich Knorr Karl-Heinz Engel Volker Heinz 《Comprehensive Reviews in Food Science and Food Safety》2021,20(4):3225-3266
The last two decades saw a steady increase of high hydrostatic pressure (HHP) used for treatment of foods. Although the science of biomaterials exposed to high pressure started more than a century ago, there still seem to be a number of unanswered questions regarding safety of foods processed using HHP. This review gives an overview on historical development and fundamental aspects of HHP, as well as on potential risks associated with HHP food applications based on available literature. Beside the combination of pressure and temperature, as major factors impacting inactivation of vegetative bacterial cells, bacterial endospores, viruses, and parasites, factors, such as food matrix, water content, presence of dissolved substances, and pH value, also have significant influence on their inactivation by pressure. As a result, pressure treatment of foods should be considered for specific food groups and in accordance with their specific chemical and physical properties. The pressure necessary for inactivation of viruses is in many instances slightly lower than that for vegetative bacterial cells; however, data for food relevant human virus types are missing due to the lack of methods for determining their infectivity. Parasites can be inactivated by comparatively lower pressure than vegetative bacterial cells. The degrees to which chemical reactions progress under pressure treatments are different to those of conventional thermal processes, for example, HHP leads to lower amounts of acrylamide and furan. Additionally, the formation of new unknown or unexpected substances has not yet been observed. To date, no safety-relevant chemical changes have been described for foods treated by HHP. Based on existing sensitization to non-HHP-treated food, the allergenic potential of HHP-treated food is more likely to be equivalent to untreated food. Initial findings on changes in packaging materials under HHP have not yet been adequately supported by scientific data. 相似文献
993.
994.
R. Abirami T.S. Senthil SP. Keerthana R. Yuvakkumar G. Ravi Mehboobali Pannipara Abdullah G. Al-Sehemi 《Ceramics International》2021,47(13):18122-18131
ZnTiO3 nanoparticles and Ag-Fe co-doped ZnTiO3 nanoparticles were prepared using sol–gel method. The prepared samples were annealed at 700 °C and showed pure hexagonal ZnTiO3. All the samples were characterized by using X-ray diffraction (XRD), field-emission scanning electron microscope, energy-dispersive X-ray analysis, and UV analyses. The result showed that the hexagonal structure of Ag-Fe ZnTiO3 is affected with the increase in Ag-Fe concentrations. The zinc titanate nanoparticles were used for determining the degradation of cationic dye. Photocatalytic activity of ZnTiO3 nanoparticles was studied and compared with that of bare control. The results showed enhanced photocatalytic activity of the Ag-Fe co-doped ZnTiO3 compared to pure ZnTiO3, showing that the Ag-Fe co-doping deposition has a major function in enhancing the degradation capability of cationic dye. 相似文献
995.
Christian Heubner Sebastian Maletti Henry Auer Juliane Hüttl Karsten Voigt Oliver Lohrberg Kristian Nikolowski Mareike Partsch Alexander Michaelis 《Advanced functional materials》2021,31(51):2106608
The development of rechargeable batteries with high-energy density is critical for future decarbonization of transportation. Anode-free Li-ion batteries, using a bare current collector at the anode side without any excess of Li, provide the highest volumetric energy density ( > 1500 Wh L−1) among all possible cell configurations. Furthermore, elimination of the anode material coating reduces material consumption and greatly simplifies cell production, which in turn lowers costs. Although significant progress has been made recently by the application of modified current collectors, optimized cycling parameters and improved liquid electrolytes, insufficient efficiencies, and dendritic growth during lithium plating lead to poor cycle life of typically less than 100 cycles as well as safety issues. Alternatively, very recent studies have demonstrated anode-free solid-state batteries that combine the benefits of high energy anode-free cell configuration and solid-state systems with high safety, exceeding 1000 cycles. This review provides an overview of recent developments toward anode-free solid-state batteries and highlights the current issues and challenges in this nascent field. It is concluded that, although major challenges remain at the present, the lessons learned in the fields of liquid electrolytes and solid-state lithium metal batteries can accelerate the development of anode-free solid-state batteries of practical relevance. 相似文献
996.
Valerie Bríd OLeary Oliver James Dolly Cyril Hschl Marie erna Saak Victor Ovsepian 《International journal of molecular sciences》2021,22(1)
An enigmatic localized pneumonia escalated into a worldwide COVID-19 pandemic from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). This review aims to consolidate the extensive biological minutiae of SARS-CoV-2 which requires decipherment. Having one of the largest RNA viral genomes, the single strand contains the genes ORF1ab, S, E, M, N and ten open reading frames. Highlighting unique features such as stem-loop formation, slippery frameshifting sequences and ribosomal mimicry, SARS-CoV-2 represents a formidable cellular invader. Hijacking the hosts translational engine, it produces two polyprotein repositories (pp1a and pp1ab), armed with self-cleavage capacity for production of sixteen non-structural proteins. Novel glycosylation sites on the spike trimer reveal unique SARS-CoV-2 features for shielding and cellular internalization. Affording complexity for superior fitness and camouflage, SARS-CoV-2 challenges diagnosis and vaccine vigilance. This review serves the scientific community seeking in-depth molecular details when designing drugs to curb transmission of this biological armament. 相似文献
997.
Desiree Schütz Sascha Rode Clarissa Read Janis A. Müller Bernhard Glocker Konstantin M. J. Sparrer Oliver T. Fackler Paul Walther Jan Münch 《Advanced functional materials》2021,31(40):2104814
Self-assembling peptide nanofibrils (PNF) have gained increasing attention as versatile molecules in material science and biomedicine. One important application of PNF is to enhance retroviral gene transfer, a technology that has been central for gene therapy approaches. The best-investigated and commercially available PNF is derived from a 12-mer peptide termed EF-C. The mechanism of transduction enhancement depends on the polycationic surface of EF-C PNF, which bind to the negatively charged membranes of viruses and cells, thereby overcoming electrostatic repulsions and increasing virion attachment and fusion. To better understand how EF-C PNF interact with the cell surface, scanning electron and time-lapse confocal microscopy were performed. The fibrils are found to be actively engaged by cellular protrusions such as filopodia. Consequently, chemical suppression of protrusion formation abrogates fibril binding and virion delivery to the cell surface of immortalized and primary T cells. Vice versa, induction of plasma membrane blebs result in increased fibril binding. Thus, the mechanism of PNF-mediated viral transduction enhancement involves an active engagement of virus-loaded fibrils by cellular protrusions, which may explain its superior performance over soluble transduction enhancers. 相似文献
998.
999.
Abhishek Sarkar Ruzica Djenadic Di Wang Christina Hein Ralf Kautenburger Oliver Clemens Horst Hahn 《Journal of the European Ceramic Society》2018,38(5):2318-2327
Multicomponent oxides with perovskite type of structure containing up to 10 different cations in equiatomic amounts have been synthesised for the first time. Out of eleven systems synthesised, only six systems crystallised as single phase perovskite type compounds with random and homogenous cation distribution on the respective sites. The formation of phase pure 10-cationic system, (Gd0.2La0.2Nd0.2Sm0.2Y0.2)(Co0.2Cr0.2Fe0.2Mn0.2Ni0.2)O3, in contrast to the multiphase mixtures observed in five of the lower entropy systems (containing 6 cations) indicates a possible role of entropy in the stabilisation of a single phase crystal structure. The entropy driven structural stabilisation effect is further supported by the reversible phase transformation, from single phase to multiple phase upon cyclic heat treatment, observed in the (Gd0.2La0.2Nd0.2Sm0.2Y0.2)MnO3 system. This type of entropic signature has been observed in rocksalt based high entropy oxide systems. However, it has not been reported before for perovskite based compounds, as shown in this study. 相似文献
1000.
Pedro Álvarez-Cervantes Juan Carlos Cancino-Díaz Héctor Enrique Fabela-Illescas Raquel Cariño-Cortés Edgar Oliver López-Villegas José Alberto Ariza‑Ortega Helen Belefant-Miller Gabriel Betanzos-Cabrera 《International Journal of Food Science & Technology》2021,56(10):5089-5096
Most of the work on pomegranate antioxidant and antibacterial activity has been carried out with solvent extracts of different plant or fruit parts. Biosensitive compounds in juice may be subject to oxidation, reducing their biological activities. Microencapsulation can be used to protect compounds, allowing its incorporation into functional foods. This study aimed at investigating antioxidant activity after in vitro digestion of microencapsulated juice. Pomegranate juice was encapsulated by spray drying its maltodextrin and gum arabic. The average diameter of the microcapsules was 10–50 µm. We evaluated the bioaccessibility of microencapsulated phenolic compounds by using an in vitro enzymatic digestion. The total phenolic content in digested microencapsulated juice was three times greater than in undigested, indicating that the compounds were made bioaccessible. Digestion also increased antioxidant activity, as measured by ABTS●+ or by DPPH●. Additionally, microencapsulated pomegranate juice showed antibacterial activity against the nine bacteria species tested. 相似文献