181 research outputs found

    Management and investigation of neonatal encephalopathy: 2017 update.

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    This review discusses an approach to determining the cause of neonatal encephalopathy, as well as current evidence on resuscitation and subsequent management of hypoxic-ischaemic encephalopathy (HIE). Encephalopathy in neonates can be due to varied aetiologies in addition to hypoxic-ischaemia. A combination of careful history, examination and the judicious use of investigations can help determine the cause. Over the last 7 years, infants with moderate to severe HIE have benefited from the introduction of routine therapeutic hypothermia; the number needed to treat for an additional beneficial outcome is 7 (95% CI 5 to 10). More recent research has focused on optimal resuscitation practices for babies with cardiorespiratory depression, such as delayed cord clamping after establishment of ventilation and resuscitation in air. Around a quarter of infants with asystole at 10 min after birth who are subsequently cooled have normal outcomes, suggesting that individualised decision making on stopping resuscitation is needed, based on access to intensive treatment unit and early cooling. The full benefit of cooling appears to have been exploited in our current treatment protocols of 72 hours at 33.5°C; deeper and longer cooling showed adverse outcome. The challenge over the next 5-10 years will be to assess which adjunct therapies are safe and optimise hypothermic brain protection in phase I and phase II trials. Optimal care may require tailoring treatments according to gender, genetic risk, injury severity and inflammatory status

    Systems Biology Model of Cerebral Oxygen Delivery and Metabolism During Therapeutic Hypothermia: Application to the Piglet Model

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    Hypoxic ischaemic encephalopathy (HIE) is a significant cause of death and disability. Therapeutic hypothermia (TH) is the only available standard of treatment, but 45-55% of cases still result in death or neurodevelopmental disability following TH. This work has focussed on developing a new brain tissue physiology and biochemistry systems biology model that includes temperature effects, as well as a Bayesian framework for analysis of model parameter estimation. Through this, we can simulate the effects of temperature on brain tissue oxygen delivery and metabolism, as well as analyse clinical and experimental data to identify mechanisms to explain differing behaviour and outcome. Presented here is an application of the model to data from two piglets treated with TH following hypoxic-ischaemic injury showing different responses and outcome following treatment. We identify the main mechanism for this difference as the Q10 temperature coefficient for metabolic reactions, with the severely injured piglet having a median posterior value of 0.133 as opposed to the mild injury value of 5.48. This work demonstrates the use of systems biology models to investigate underlying mechanisms behind the varying response to hypothermic treatment

    Melatonin and/or erythropoietin combined with hypothermia in a piglet model of perinatal asphyxia

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    AAs therapeutic hypothermia is only partially protective for neonatal encephalopathy, safe and effective adjunct therapies are urgently needed. Melatonin and erythropoietin show promise as safe and effective neuroprotective therapies. We hypothesized that melatonin and erythropoietin individually augment 12-h hypothermia (double therapies) and hypothermia + melatonin + erythropoietin (triple therapy) leads to optimal brain protection. Following carotid artery occlusion and hypoxia, 49 male piglets (<48 h old) were randomized to: (i) hypothermia + vehicle (n = 12), (ii) hypothermia + melatonin (20 mg/kg over 2 h) (n = 12), (iii) hypothermia + erythropoietin (3000 U/kg bolus) (n = 13) or (iv) tripletherapy (n = 12). Melatonin, erythropoietin or vehicle were given at 1, 24 and 48 h after hypoxia–ischaemia. Hypoxia–ischaemia severity was similar across groups. Therapeutic levels were achieved 3 hours after hypoxia–ischaemia for melatonin (15–30 mg/l) and within 30 min of erythropoietin administration (maximum concentration 10 000 mU/ml). Compared to hypothermia + vehicle, we observed faster amplitude-integrated EEG recovery from 25 to 30 h with hypothermia + melatonin (P = 0.02) and hypothermia + erythropoietin (P = 0.033) and from 55 to 60 h with tripletherapy (P = 0.042). Magnetic resonance spectroscopy lactate/N-acetyl aspartate peak ratio was lower at 66 h in hypothermia + melatonin (P = 0.012) and tripletherapy (P = 0.032). With hypothermia + melatonin, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelled-positive cells were reduced in sensorimotor cortex (P = 0.017) and oligodendrocyte transcription factor 2 labelled-positive counts increased in hippocampus (P = 0.014) and periventricular white matter (P = 0.039). There was no reduction in terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelled-positive cells with hypothermia + erythropoietin, but increased oligodendrocyte transcription factor 2 labelled-positive cells in 5 of 8 brain regions (P < 0.05). Overall, melatonin and erythropoietin were safe and effective adjunct therapies to hypothermia. Hypothermia + melatonin double therapy led to faster amplitude-integrated EEG recovery, amelioration of lactate/N-acetyl aspartate rise and reduction in terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelled-positive cells in the sensorimotor cortex. Hypothermia + erythropoietin doubletherapy was in association with EEG recovery and was most effective in promoting oligodendrocyte survival. Tripletherapy provided no added benefit over the double therapies in this 72-h study. Melatonin and erythropoietin influenced cell death and oligodendrocyte survival differently, reflecting distinct neuroprotective mechanisms which may become more visible with longer-term studies. Staggering the administration of therapies with early melatonin and later erythropoietin (after hypothermia) may provide better protection; each therapy has complementary actions which may be time critical during the neurotoxic cascade after hypoxia–ischaemia

    Advanced surface treatments for medium-velocity superconducting RF cavities for high accelerating gradient continuous-wave operation

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    Nitrogen-doping and furnace-baking are advanced high-Q0 recipes developed for 1.3 GHz TESLA-type cavities. These treatments will significantly benefit the high-Q0 linear accelerator community if they can be successfully adapted to different cavity styles and frequencies. Strong frequency- and geometry- dependence of these recipes makes the technology transfer amongst different cavity styles and frequencies far from straightforward, and requires rigorous study. Upcoming high-Q0 continuous-wave linear accelerator projects, such as the proposed Michigan State University Facility for Rare Isotope Beam Energy Upgrade, and the underway Fermilab's Proton Improvement Plan-II, could benefit enormously from adapting these techniques to their beta_opt = 0.6 ~650 MHz 5-cell elliptical superconducting rf cavities, operating at an accelerating gradient of around ~17 MV/m. This is the first investigation of the adaptation of nitrogen doping and medium temperature furnace baking to prototype 644 MHz beta_opt = 0.65 cavities, with the aim of demonstrating the high-Q0 potential of these recipes in these novel cavities for future optimization as part of the FRIB400 project R&D. We find that nitrogen-doping delivers superior Q0, despite the sub-GHz operating frequency of these cavities, but is sensitive to the post-doping electropolishing removal step and experiences elevated residual resistance. Medium temperature furnace baking delivers reasonable performance with decreased residual resistance compared to the nitrogen doped cavity, but may require further recipe refinement. The gradient requirement for the FRIB400 upgrade project is comfortably achieved by both recipes.Comment: 16 pages, 5 figure

    Allogeneic mesenchymal stem cells improve the wound healing process of sheep skin

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    Abstract Background Skin wound healing includes a system of biological processes, collectively restoring the integrity of the skin after injury. Healing by second intention refers to repair of large and deep wounds where the tissue edges cannot be approximated and substantial scarring is often observed. The objective of this study was to evaluate the effects of mesenchymal stem cells (MSCs) in second intention healing using a surgical wound model in sheep. MSCs are known to contribute to the inflammatory, proliferative, and remodeling phases of the skin regeneration process in rodent models, but data are lacking for large animal models. This study used three different approaches (clinical, histopathological, and molecular analysis) to assess the putative action of allogeneic MSCs at 15 and 42 days after lesion creation. Results At 15 days post-lesion, the wounds treated with MSCs showed a higher degree of wound closure, a higher percentage of re-epithelialization, proliferation, neovascularization and increased contraction in comparison to a control group. At 42 days, the wounds treated with MSCs had more mature and denser cutaneous adnexa compared to the control group. The MSCs-treated group showed an absence of inflammation and expression of CD3+ and CD20+. Moreover, the mRNA expression of hair-keratine (hKER) was observed in the MSCs-treated group 15 days after wound creation and had increased significantly by 42 days post-wound creation. Collagen1 gene (Col1α1) expression was also greater in the MSCs-treated group compared to the control group at both days 15 and 42. Conclusion Peripheral blood-derived MSCs may improve the quality of wound healing both for superficial injuries and deep lesions. MSCs did not induce an inflammatory response and accelerated the appearance of granulation tissue, neovascularization, structural proteins, and skin adnexa

    Cholinergic afferent stimulation induces axonal function plasticity in adult hippocampal granule cells.

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    Acetylcholine critically influences hippocampal-dependent learning. Cholinergic fibers innervate hippocampal neuron axons, dendrites, and somata. The effects of acetylcholine on axonal information processing, though, remain unknown. By stimulating cholinergic fibers and making electrophysiological recordings from hippocampal dentate gyrus granule cells, we show that synaptically released acetylcholine preferentially lowered the action potential threshold, enhancing intrinsic excitability and synaptic potential-spike coupling. These effects persisted for at least 30 min after the stimulation paradigm and were due to muscarinic receptor activation. This caused sustained elevation of axonal intracellular Ca(2+) via T-type Ca(2+) channels, as indicated by two-photon imaging. The enhanced Ca(2+) levels inhibited an axonal KV7/M current, decreasing the spike threshold. In support, immunohistochemistry revealed muscarinic M1 receptor, CaV3.2, and KV7.2/7.3 subunit localization in granule cell axons. Since alterations in axonal signaling affect neuronal firing patterns and neurotransmitter release, this is an unreported cellular mechanism by which acetylcholine might, at least partly, enhance cognitive processing

    Efficacy of conventional versus innovative therapies for treating skin wounds in veterinary medicine

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    open16siINTRODUCTION: The skin is the largest organ of mammals. The loss of skin integrity may induce important dysfunctions or even death. For superficial wounds, the endogenous healing mechanisms in combination with traditional wound care are sufficient to achieve functional repair. In contrast, in larger wounds, like third and fourth degree burns, chronic wound or deep ulcers it is difficult to obtain the restitutio ad integrum and fibrosis and/or scar tissue develops1,2. The aim of this study was to verify the efficacy of conventional and innovative topic treatments on skin regeneration, induced experimentally in sheep. To achieve this goal different types of investigations (clinical, molecular, histological, immunohistochemical) were performed. METHODS: Six skin lesions (4x4cm) were surgically created on the back of six healthy adult sheep; every single wound was destined, in a randomized way, to one of the following treatments: Acemannan gel, Manuka Honey, hyaluronic acid, Plasma3 (ionized gas), allogeneic mesenchymal stem cells isolated from peripheral blood (PB-MSCs). The sixth wound was the placebo. Biopsies were collected with a surgical punch (0,6x0,6 cm) at time T0, T15 and T40 days. Lesions were clinically evaluated considering the presence and color of wound fluid, the state of hydration, the wound surface/surroundings and other parameters. Histological examinations considered crust formation, re-epithelization and epidermal thickness, dermis edema, extension of granulation tissue, acute and chronic inflammation. Immunohistochemistry for evaluation of inflammation, vascularization and cell proliferation was performed using CD3, CD20, MHCII, von Willebrand factor (vWF) and KI67 antibodies. Furthermore, Real time-PCR investigated genes as V ascular endothelial growth factors (VEGF), Transforming growth factor beta 1(TGFβ1), Vimentin (VIM), Collagen 1α1 (Col1α1) and hair Keratin (hKER). RESULTS: Clinically, the lesions treated with plasma healed more rapidly respect to other treatments and a reduced bacterial load was observed. At T7 wounds treated with stem cells and plasma were less macerated than lesions treated with other therapies. At T15 the wounds treated with hyaluronic acid showed a normal state of hydration while lesions treated with Manuka Honey exhibited a normal hydration from the third week only (Acemannan gel at fourth week). From the second week onwards all wounds did not show presence of fluid and exhibited a dry and clean secondary layer. All lesions, excluded wounds treated with acemannan gel, presented a red (hyaluronic acid and plasma) and dark red (Manuka Honey, PB-MSCs) granulation tissue starting from the first week. Molecular analysis showed a correspondence between clinical and molecular/histologic results. For instance, VEGF mRNA expression confirms angiogenetic events observed at histological level while TGF-β, CD3 and CD20 mRNA/protein expression indicated the presence/absence of inflammation in the used treatments. DISCUSSION & CONCLUSIONS: Innovative therapies led to surprising results regarding regeneration of mammalian skin. Indeed, on the basis of clinical analysis, wounds treated with plasma and MSC healed more rapidly. Further examinations are ongoing in order to elucidate possible mechanisms explaining these differences. REFERENCES: 1S.Y. Broeckx, S. Maes, T. Martinello, et al (2014) Equine epidermis: a source of epithelial-like stem/progenitor cells with in vitro and in vivo regenerative capacities Stem Cells Dev, pp 1134-48. 2J.H. Spaas, C. Gomiero, S.Y. Broeckx, et al (2016) Wound healing markers after autologous and allogeneic epithelial-like stem cell treatment Cytotherapy 2016 (in press). 3E. Martines, M. Zuin, R. Cavazzana, et al. (2009) A novel plasma source for sterilization of living tissues, New J. Phys. 11, 115014.openPatruno, MARCO VINCENZO; Gomiero, Chiara; Martinello, Tiziana; Perazzi, Anna; Gemignani, F; DE BENEDICTIS, GIULIA MARIA; Ferro, Silvia; Zuin, M; Martines, E; Cordaro, Luigi; Brun, Paola; Maccatrozzo, Lisa; Broeckx, Sy; Spaas, Jh; Chiers, K; Iacopetti, IlariaPatruno, MARCO VINCENZO; Gomiero, Chiara; Martinello, Tiziana; Perazzi, Anna; Gemignani, F; DE BENEDICTIS, GIULIA MARIA; Ferro, Silvia; Zuin, M; Martines, E; Cordaro, Luigi; Brun, Paola; Maccatrozzo, Lisa; Broeckx, Sy; Spaas, Jh; Chiers, K; Iacopetti, Ilari
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