Fate of linoleic, arachidonic, and docosa-7,10,13,16-tetraenoic acids in rat testicles

A comparative study was made on the fate of linoleic, arachidonic, and docosa-7,10,13,16-tetraenoic acids in various subcellular fractions of liver and testis from rats of different ages. It was demonstrated that testicular microsomes can desaturate and elongate linoleic and arachidonic acids in a manner similar to liver microsomes, and that testicular mitochondria can convert docosa-7,10,13,16-tetraenoic acid to arachidonic acid. Testicular or liver microsomes actively desaturate linoleic acid to γ-linolenic acid and eicosa-8,11,14-trienoic acid to arachidonic acid. However, it was impossible to measure in vitro any direct conversion of adrenic acid (22:4 [n – 6]) to docosapentaenoic acid (22: 5 [n – 6]) by either liver or testicular microsomes. Docosa-7,10,13,16-tetraenoic acid is incorporated preferentially into the triglyceride fraction of total testis, mitochondria, and microsomes, while linoleic and arachidonic acids are incorporated more into phospholipids. The capacity of testicular microsomes, but not of liver microsomes, to synthesize polyunsaturated fatty acids declines with age. It is proposed that the synthesis of acids of the linoleic family proceeds in two stages, a rapid one in which arachidonic acid is made and a second, slower, one in which C22 and C24 acids are synthesized. In addition, there appears to be a cycle between microsomes and mitochondria that acts to conserve essential polyunsaturated C20 and C22 fatty acids by means of synthesis and partial degradation, respectively. This cycle would restrict the loss of essential fatty acids and might be of importance for the supply of arachidonic acid in testis under specific requirements and especially in older animals.Facultad de Ciencias Médica

Vapor-Liquid Equilibrium of Ionic Liquid 7-Methyl-1,5,7-triazabicyclo[4.4.0]dec-5-enium Acetate and Its Mixtures with Water

Ionic liquids have the potential to be used for extracting valuable chemicals from raw materials. These processes often involve water, and after extraction, the water or other chemicals must be removed from the ionic liquid, so it can be reused. To help in designing such processes, we present data on the vapor-liquid equilibrium of the system containing protic ionic liquid 7-methyl-1,5,7-triazabicyclo [ 4.4.0 ] dec-5-enium acetate, water, acetic acid, and 7-methyl-1,5,7-triazabicyclo [4.4.0] dec-5-ene. Earlier studies have only focused on mixtures of water and an ionic liquid with a stoichiometric ratio of the ions. Here, we also investigated mixtures containing an excess of the acid or base component because in real systems with protic ionic liquids, the amount of acid and base in the mixture can vary. We modeled the data using both the ePC-SAFT and NRTL models, and we compared the performance of different modeling strategies. We also experimentally determined the vapor composition for a few of the samples, but none of the modeling strategies tested could accurately predict the concentration of the acid and base components in the vapor phase.Peer reviewe

Recycling of Superbase-Based Ionic Liquid Solvents for the Production of Textile-Grade Regenerated Cellulose Fibers in the Lyocell Process

This article has a correction concerning the authors: We regret that there is an error with the author list in our original article. The authors Jussi Helminen, Paulus Hyväri, and Ilkka Kilpeläinen, all with the Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland, were mistakenly omitted. The author list should be as shown above in this Addition and Correction. DOI 10.1021/acssuschemeng.0c07773Ioncell is a Lyocell based technology for the production of manmade cellulose fibers. This technology exploits the intrinsic dissolution power of superbase-based ionic liquids (ILs) toward cellulose and the ability to form spinnable cellulose solutions. The regenerated fibers are produced via a dry-jet wet spinning process in which the cellulose filaments are stretched in an air gap before regenerating in an aqueous coagulation medium. For the commercialization of this process, it is essential to demonstrate the quantitative recovery of the solvent from the coagulation bath without impairing its solvation power. This study reports on the spinnability and recyclability of the IL 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-enium acetate ([mTBDH][OAc]) over five cycles in comparison to 1,5-diaza-bicyclo[4.3.0]non-5-enium acetate ([DBNH][OAc]). The aqueous IL solutions were recovered from the coagulation bath by successive thermal treatments under reduced pressure. Accordingly, the recycled ILs were utilized to dissolve 13 wt % cellulose pulp in each cycle without the addition of make-up IL. While using [mTBDH][OAc], the pulp was completely dissolved and processed into easily spinnable cellulose solutions during all five cycles, whereas the ability to dissolve pulp was completely lost after the first recovery cycle when using [DBNH][OAc]. The composition of the recovered ILs and extent of side-products generated in the adopted process was analyzed in detail. This includes characterization of the rheological properties of the solutions as well as the macromolecular and mechanical properties of the regenerated fibers. In addition, we review the toxicity of both solvents using Vibrio fischeri bacteria. Finally, the spun fibers from all [mTBDH][OAc] spinning trials were combined to produce a demonstration dress (Paju), designed and sewn by Marimekko Design House in Finland.Peer reviewe

Fate of linoleic, arachidonic, and docosa-7,10,13,16-tetraenoic acids in rat testicles

A comparative study was made on the fate of linoleic, arachidonic, and docosa-7,10,13,16-tetraenoic acids in various subcellular fractions of liver and testis from rats of different ages. It was demonstrated that testicular microsomes can desaturate and elongate linoleic and arachidonic acids in a manner similar to liver microsomes, and that testicular mitochondria can convert docosa-7,10,13,16-tetraenoic acid to arachidonic acid. Testicular or liver microsomes actively desaturate linoleic acid to γ-linolenic acid and eicosa-8,11,14-trienoic acid to arachidonic acid. However, it was impossible to measure in vitro any direct conversion of adrenic acid (22:4 [n – 6]) to docosapentaenoic acid (22: 5 [n – 6]) by either liver or testicular microsomes. Docosa-7,10,13,16-tetraenoic acid is incorporated preferentially into the triglyceride fraction of total testis, mitochondria, and microsomes, while linoleic and arachidonic acids are incorporated more into phospholipids. The capacity of testicular microsomes, but not of liver microsomes, to synthesize polyunsaturated fatty acids declines with age. It is proposed that the synthesis of acids of the linoleic family proceeds in two stages, a rapid one in which arachidonic acid is made and a second, slower, one in which C22 and C24 acids are synthesized. In addition, there appears to be a cycle between microsomes and mitochondria that acts to conserve essential polyunsaturated C20 and C22 fatty acids by means of synthesis and partial degradation, respectively. This cycle would restrict the loss of essential fatty acids and might be of importance for the supply of arachidonic acid in testis under specific requirements and especially in older animals.Facultad de Ciencias Médica

Characterisation of cellulose pulps isolated from Miscanthus using a low-cost acidic ionic liquid

The ionoSolv pretreatment generates a cellulose pulp by extracting hemicellulose and lignin using low-cost ionic liquids. In this study, cellulose pulp was obtained from Miscanthus × giganteus using the protic ionic liquid triethylammonium hydrogen sulfate [N2220][HSO4] with 20% water as a co-solvent and characterised in detail for its material properties as a function of pretreatment severity. We measured the particle size distribution, porosity and crystallinity of the unbleached pulps and the molar weight distribution of the cellulose contained within. We report that the surface area increased and the size of the pulp particles decreased as ionoSolv processing progressed. While the native cellulose I structure was maintained, the average degree of polymerisation of the cellulose was reduced to a DPn of around 300, showing the cellulose polymers are shortened. We correlate the pulp properties with enzymatic saccharification yields, concluding that enzymatic saccharification of the cellulose after ionoSolv pretreatment is mainly enhanced by removing hemicellulose and lignin. We also observed that overtreatment deteriorated saccharification yield and that this coincides with cellulose fibrils becoming coated with pseudolignin redeposited from the ionic liquid solution, as demonstrated by FT-IR spectroscopy. Pseudolignin deposition increases the apparent lignin content, which is likely to increase chemical demand in bleaching, suggesting that both glucose release and material use benefit from a minimum lignin content. Overall, this study demonstrates that cellulose pulps isolated with ionoSolv processing are not only a promising intermediate for high-yield release of purified glucose for biorefining, but also have attractive properties for materials applications that require cellulose I fibrils

Polarized actin and VE-Cadherin dynamics regulate junctional remodelling and cell migration during sprouting angiogenesis

VEGFR-2/Notch signalling regulates angiogenesis in part by driving the remodelling of endothelial cell junctions and by inducing cell migration. Here, we show that VEGF-induced polarized cell elongation increases cell perimeter and decreases the relative VE-cadherin concentration at junctions, triggering polarized formation of actin-driven junction-associated intermittent lamellipodia (JAIL) under control of the WASP/WAVE/ARP2/3 complex. JAIL allow formation of new VE-cadherin adhesion sites that are critical for cell migration and monolayer integrity. Whereas at the leading edge of the cell, large JAIL drive cell migration with supportive contraction, lateral junctions show small JAIL that allow relative cell movement. VEGFR-2 activation initiates cell elongation through dephosphorylation of junctional myosin light chain II, which leads to a local loss of tension to induce JAIL-mediated junctional remodelling. These events require both microtubules and polarized Rac activity. Together, we propose a model where polarized JAIL formation drives directed cell migration and junctional remodelling during sprouting angiogenesis

Viscoelastic Testing and Coagulopathy of Traumatic Brain Injury

A unique coagulopathy often manifests following traumatic brain injury, leading the clinician down a difficult decision path on appropriate prophylaxis and therapy. Conventional coagulation assays—such as prothrombin time, partial thromboplastin time, and international normalized ratio—have historically been utilized to assess hemostasis and guide treatment following traumatic brain injury. However, these plasma-based assays alone often lack the sensitivity to diagnose and adequately treat coagulopathy associated with traumatic brain injury. Here, we review the whole blood coagulation assays termed viscoelastic tests and their use in traumatic brain injury. Modified viscoelastic tests with platelet function assays have helped elucidate the underlying pathophysiology and guide clinical decisions in a goal-directed fashion. Platelet dysfunction appears to underlie most coagulopathies in this patient population, particularly at the adenosine diphosphate and/or arachidonic acid receptors. Future research will focus not only on the utility of viscoelastic tests in diagnosing coagulopathy in traumatic brain injury, but also on better defining the use of these tests as evidence-based and/or precision-based tools to improve patient outcomes

Sustainable design of biorefinery processes: existing practices and new methodology

Nowadays, eco-designing products is increasingly practiced. The next challenge for sustain- ability is to optimize production processes. Biorefi neries are particularly concerned with this improve- ment, because they use renewable resources. To identify the contribution of transformation processes to the overall environmental impacts, Life Cycle Assessment (LCA) appears as the adequate method. A literature review highlights that LCA is mainly performed on biorefi neries to compare biomass feed- stocks between them and to a fossil reference. Another part of environmental LCA compares the impacts of different processing routes. Nevertheless, these evaluations concern already designed pro- cesses. Generally, processes are considered as a unique operation in assessments. However, some criteria like operating can notably modify environmental burdens. The eco-design of biorefi nery pro- cesses can be guided by coupling process simulation to LCA. This method has been emerging in the chemical sector in recent years. Consequently, this paper proposes a new methodological approach to assessing the complete sustainability of biorefi nery processes, since its fi rst design stages. In addi- tion to coupling process simulation and environmental LCA, the other pillars of sustainability will be assessed. Indeed, Life Cycle Costing and Social Life Cycle Assessment can be performed to obtain an integrated methodological framework. The simultaneous optimization of the environmental, economic, and social performances of the process can lead to antagonist ways of improving. Consequently, compromises should be realized. Thereby, the multi-objective optimization can be accomplished by a metaheuristic method supported by a decision-making tool. Finally, the main limits of this method and some perspectives and ways for improving are discussed