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P NMR spectra were recorded from tail muscles of the prawn Palaemon serratus, at rest, after exhaustive work and during subsequent recovery. At rest, the spectra indicated concentrations of phosphoarginine and ATP in good agreement with those obtained from resting fast skeletal muscles in mammals, which are characterized by a high phosphocreatine/P ratio. Following exhaustive work, phosphoarginine dropped by ca. 60% and ATP by 20%, while inorganic phosphate increased by 160%. The increase in inorganic phosphate immediately after contractions and in the first minutes of recovery corresponded partially to the changes in phosphoarginine and ATP. During recovery, the decrease of inorganic phosphate balanced the resynthesized phosphoarginine which was fully replenished within 30-40 min. The position of the inorganic phosphate resonance peak was used to monitor changes in intracellular pH (pH). The average pH in resting tail muscles was 7.20. After stimulation it was observed to decrease by 0.22 units. The return to pre-stimulation value was not achieved within 45 min. A NMR index (ATP+Arg-P)/(ATP+Arg-P+P) was calculated to characterize the extent of energetic changes caused by exercise. [ABSTRACT FROM AUTHOR]

Lactate concentration was measured in the abdominal muscle of the shrimp Palaemon serratus. Rapid and seasonal temperature changes result in an increase of the lactate content of approximately 3-4 fold. Lactate dehydrogenase from the abdominal muscle exhibits a temperature dependent pyruvate inhibition with pyruvate as substrate. The kinetic parameters of lactate dehydrogenase from Palaemon serratus are found to vary during rapid temperature changes: V increases with temperature from 0.06 μmol min (mg protein) at 10°C to 0.28 μmol min (mg protein) at 30°C with lactate as substrate, and from 5.5 μmol min (mg protein) at 10°C to 26.2 μmol min (mg protein) at 30°C, with pyruvate (Table 1). The Hill coefficient n, decreases with temperature from 2.2 to 1.2 when the pyruvate reduction is examined, but remains near 1.2 when the activity is measured with lactate as substrate (Table 1). The S values for lactate show a tendency to increase below 30 °C (18.9 mM l at 20 °C) whereas the S for pyruvate is found to increase greatly with temperature (0.004 mM l at 10 °C and 0.06 mM l at 20 °C). Long term temperature changes involve variations of lactate dehydrogenase activity leading to inverse thermal compensation (Table 2). Activation energy (about 56 kJ both with pyruvate and lactate) does not vary during the year, suggesting that temperature adaptation does not induce important catalytic changes (Table 3). [ABSTRACT FROM AUTHOR]

Warm autoimmune hemolytic anemia (wAIHA) is a rare acquired autoimmune disease mediated by antibodies targeting red blood cells. The involvement of CD4 T-helper cells has been scarcely explored, with most findings extrapolated from animal models. Here, we performed quantification of both effector T lymphocytes (Teff) and regulatory T cells (Treg), associated with functional and transcriptomic analyses of Treg in human wAIHA. We observed a shift of Teff toward a Th17 polarization concordant with an increase in serum interleukin-17 concentration that correlates with red blood cell destruction parameters, namely lactate dehydrogenase and bilirubin levels. A decrease in circulating Treg, notably effector Treg, associated with a functional deficiency, as represented by their decrease capability to inhibit Teff proliferation, were also observed. Treg deficiency was associated with a reduced expression of Foxp3, the master transcription factor known to maintain the Treg phenotype stability and suppressive functions. Transcriptomic profiling of Treg revealed activation of the tumor necrosis facto (TNF)-α pathway, which was linked to increased serum TNF-α concentrations that were twice as high as in controls. Treg transcriptomic profiling also suggested that post-translational mechanisms possibly accounted for Foxp3 downregulation and Treg dysfunctions. Since TNF-α participates in the rupture of immune tolerance during wAIHA, its inhibition could be of interest. To this end, the effects of fostamatinib, a SYK inhibitor, were investigated in vitro, and we showed that besides the inhibition of erythrocyte phagocytosis by monocytes, fostamatinib is also able to dampen TNF-α production, thus appearing as a promising multitargeting therapy in wAIHA (clinicaltrials gov. Identifier: NCT02158195).

Recently developed cell-based therapies have shown potential for graft-versus-host disease (GvHD) mitigation. Our team previously developed a protocol to generate human monocyte-derived suppressor Cells (HuMoSC), a subpopulation of CD33+ suppressor cells of monocytic origin. CD33+HuMoSC successfully reduced xenoGvHD severity in NOD/SCID/IL-2Rγc -/- (NSG) mice. While CD33+ HuMoSC culture supernatant inhibits T cell activation and proliferation, the recovery of CD33+ HuMoSC immunosuppressive cells and the subsequent production of their supernatant is limited. An attractive solution would be to use both the CD33+ and the large number of CD14+ cells derived from our protocol. Here, we assessed the immunoregulatory properties of the CD14+HuMoSC supernatant and demonstrated that it inhibited both CD4 and CD8 T cell proliferation and decreased CD8 cytotoxicity. In vivo , injection of CD14+HuMoSC supernatant reduced xenoGvHD in NSG mice. Furthermore, CD14+HuMoSC supernatant maintained its immunoregulatory properties in an inflammatory environment. Proteomic and multiplex analyses revealed the presence of immunosuppressive proteins such as GPNMB, galectin-3 and IL-1R(A) Finally, CD14+HuMoSC supernatant can be produced using good manufacturing practices and be used as complement to current immunosuppressive drugs. CD14+HuMoSC supernatant is thus a promising therapy for preventing GvHD. ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gérard, Thébault, Lamarthée, Genet, Cattin, Brazdova, Janikashvili, Cladière, Ciudad, Ouandji, Ghesquière, Greigert, Tinel, Adotevi, Saas, Samson, Audia and Bonnotte.)

This study aimed to assess the implication of mucosal-associated invariant T (MAIT) cells in GCA. Blood samples were obtained from 34 GCA patients (before and after 3 months of treatment with glucocorticoids (GC) alone) and compared with 20 controls aged >50 years. MAIT cells, defined by a CD3 + CD4 - TCRγδ - TCRVα7.2 + CD161 + phenotype, were analyzed by flow cytometry. After sorting, we assessed the ability of MAIT cells to proliferate and produce cytokines after stimulation with anti CD3/CD28 microbeads or IL-12 and IL-18. MAIT were stained in temporal artery biopsies (TAB) by confocal microscopy. MAIT cells were found in the arterial wall of positive TABs but was absent in negative TAB. MAIT frequency among total αβ-T cells was similar in the blood of patients and controls (0.52 vs. 0.57%; P = 0.43) and not modified after GC treatment (P = 0.82). Expression of IFN-γ was increased in MAIT cells from GCA patients compared to controls (44.49 vs. 32.9%; P = 0.029), and not modified after 3 months of GC therapy (P = 0.82). When they were stimulated with IL-12 and IL-18, MAIT from GCA patients produced very high levels of IFN-γ and displayed a stronger proliferation compared with MAIT from controls (proliferation index 3.39 vs. 1.4; P = 0.032). In GCA, the functional characteristics of MAIT cells are modified toward a pro-inflammatory phenotype and a stronger proliferation capability in response to IL-12 and IL-18, suggesting that MAIT might play a role in GCA pathogenesis. Our results support the use of treatments targeting IL-12/IL-18 to inhibit the IFN-γ pathway in GCA., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Immunosuppressive cell-based therapy is a recent strategy for controlling Graft- versus -Host Disease (GvHD). Such cells ought to maintain their suppressive function in inflammatory conditions and in the presence of immunosuppressive agents currently used in allogeneic hematopoietic cell transplantation (allo-HCT). Moreover, these therapies should not diminish the benefits of allo-HCT, the Graft- versus -Leukemia (GvL) effect. We have previously reported on a novel subset of human monocyte-derived suppressor cells (HuMoSC) as a prospective approach for controlling GvHD.Objective., The objective of this study was to explore the therapeutic relevance of the HuMoSC in clinical conditions., Methods: Immune regulatory functions of HuMoSC were assessed in inflammatory conditions and in the presence of immunosuppressants. The therapeutic efficiency of the association of HuMoSC with immunosuppressants was evaluated in an experimental model of GvHD induced by human PBMC in NOD/SCID/IL2-Rγ c -/- (NSG) mice., Interestingly, the inhibitory functions of HuMoSC against T lymphocytes and their ability to polarize Treg are preserved, in vitro , in inflammatory environments and are not affected by immunosuppressive agents. In vivo , the association of HuMoSC-based treatment with an immunosuppressive drug showed a synergistic effect for controlling GvHD. Furthermore, HuMoSC control GvHD while preserving GvL effect in a xeno-GvHD conditioned mouse model with cell neoplasm (CAL-1). HuMoSC are generated according to good manufacturing practices (GMP) and we demonstrated that these cells tolerate long-term preservation with unaltered phenotype and function.Conclusion., HuMoSC-based therapy represents a promising approach for controlling GvHD and could be quickly implemented in clinical practice., Competing Interests: The authors declare that they have no conflict of interest., (© 2021 The Author(s). Published with license by Taylor & Francis Group, LLC.)

The quality of decorative laminates boards depends on the impregnation process of Kraft papers with a phenolic resin, which constitute the raw materials for the manufacture of the cores of such boards. In the laminates industries, the properties of resins are adapted via their syntheses, usually by mixing phenol and formaldehyde in a batch, where additives, temperature and stirring parameters can be controlled. Therefore, many possibilities of preparation of phenolic resins exist, that leads to different combinations of physico-chemical properties. In this article, the properties data of eight phenolic resins synthetized with different parameters of pH and reaction times at 60 °C and 90 °C are presented: the losses of pH after synthesis and the dynamic viscosities measured after synthesis and once the solid content is adjusted to 45%w/w in methanol. Data acquired by Differential Scanning Calorimetry (DSC) of the resins and Inverse Gas Chromatography (IGC) of cured solids are given as well.

The coordinated variations of the adenylate energy charge and ATP/ADP ratio were modeled and a function that depends on the numerical value of the adenylate kinase-catalyzed reaction has been derived. The model allows sensitive detection of the effects of xenobiotics on adenylate kinase and its cellular environment and offers a robust estimation of the direct or indirect effects of pollutants on the adenylate kinase system: data obtained in laboratory studies on shrimp exposed to cadmium and in field studies on oysters either exposed to polychloro-biphenyl compounds or located in a heavily polluted area indicate that xenobiotics affect the adenylate kinase reaction directly or by changing its cellular environment. These results demonstrate that application of the model to the treatment of ecotoxicological data allows detection of energetic changes that would have been missed by simple analysis of the usual energetic parameters, and should overcome problems encountered in using energetic parameters during assessment of pollution monitoring., (Copyright 2000 Academic Press.)

31P nuclear magnetic resonance (NMR) was used to study the major phosphorylated compounds visible in perchloric extracts of three body regions of the vestimentiferan worm Riftia pachyptila: winged vestimentum, trunk and segmented posterior opisthosome. Two phosphagens (PGs) were present in vestimentum and opisthosome. The major resonance corresponded to those of phosphoarginine and phosphotaurocyamine, which cannot be discriminated on 31P NMR spectra. We have identified four distinct phosphodiesters (PDEs) in these tissues: glycerophosphorylethanolamine (GPE), serine ethanolamine phosphodiester (SEP), glycero-phosphorylcholine (GPC) and threonine ethanolamine phosphodiester (TEP). Three phosphonates or derivates (PAs) were observed in the three body regions. The minor one was identified as 2-aminoethyl phosphonate (2-AEP). The phosphorus profile of the trunk was appreciably different: one additional resonance in the PDE region and only one phosphagen peak were observed.

Regulation of the coordinated adenylate energy charge (AEC) and ATP/ADP ratio variations was studied with the aid of computer-made simulations. When the equilibrium state for the adenylate kinase-catalyzed reaction has been assumed, the function describing the coordinated AEC and ATP/ADP ratio variations can be simply derived from the formulas describing these 2 parameters. The model was used to analyze incidence of AMP deamination in the coordinated regulation of cellular energy metabolism.

Myoadenylate deaminase activity was measured, by using a specific assay technique, in a wide range of animal species, including four invertebrates, one cyclostome, 13 chondrosteans, one teleost and one mammal. The results are discussed considering the known genetic events that have lead to the appearance of the higher vertebrates myoadenylate deaminase molecular form. It is proposed that, during the extensive gene duplication that occurred in the beginning of vertebrate evolution, genetic modification of the myoadenylate deaminase molecule took place in at least two different taxa: the one that evolved to rajiform elasmobranch fishes and the other to the land vertebrates.

In vivo 31P NMR has been used to characterize the phosphorylated compounds present in the heart from vertebrate ectotherms. The perfused hearts from all animals experimented showed prominent resonances between the inorganic phosphate and phosphocreatine peaks. The pattern of these compounds was found to be different in the heart of the different species. As shown by 31P and proton NMR of perchloric extracts, the chemical shift of some of the compounds was characteristic of glycerophosphorylcholine, glycerophosphorylinositol, phosphorylcholine, phosphorylserine, phosphorylethanolamine and phosphoenolpyruvate. The non-identified resonances were found to be phosphodiesters, as demonstrated by alkaline phosphatase hydrolysis. The physiological significance of these high levels of phosphodiesters in the heart from vertebrate ectotherms is discussed.

Bioassay experiments were performed after exposure for 96 hr to various concentrations of trichlorophenoxyacetic acid (2,4,5.T). The sensitivity of juvenile trout was considerably higher than that of mature animals. The activity of the microsomal Ca2+ ATPase in trout gill under the effect of 2,4,5.T was investigated. In vitro studies showed an inhibitory effect on the Ca2+ ATPase, occurring at sublethal concentrations of the herbicide. In vivo exposure to various sublethal concentrations of 2,4,5.T during 96 hr involved a significant inhibition of the microsomal Ca2+ ATPase. The sensitivity of the microsomal Ca2+ ATPase from gills to 2,4,5.T is related to the toxicity of this herbicide.

31P NMR has been used to observe the in vivo phosphometabolite concentrations in the tail musculature from the prawn Palaemon elegans, at rest and after escape swimming and subsequent recovery. Muscular fatigue corresponds to a 60% breakdown of phosphoarginine, and a 45% increase of sugar phosphates. The pHi fell from 7.10 to 6.86. During recovery, the sugar phosphates and arginine phosphate are replenished after 20 minutes. The ATP concentration did not change throughout the experiment. The pHi was restored within 20 minutes.