76 research outputs found
A comparison of early and late treatments on allodynia and its chronification in experimental neuropathic pain
Restauration dâune zone corallienne dĂ©gradĂ©e et implantation d'un jardin corallien Ă Bora Bora, PolynĂ©sie française
The restoration of coral reef habitats by coral transplantation is a hot topic in the news
toda y due to the accelerating degradation of the coral reef ecosystem all over the world. There
is much discussion about research programs for the transplantation of corals and about ac tuai
field realizations and the motivation for coral reef restoration. But the implementation of such
a project depends on a social request considering local or global cultural and economical situations
. Projects are very costly and only applicable when important economical interests are
involved such as the fight against erosion or tourism development.
In the lagoon of Bora Bora in French Polynesia, a fringing zone, degraded by coral sand
extractions, led to an erosion of the coast damaging local private property in a sec tor weil oriented
toward tourism activities. The reconstruction of this degraded site (20,000 sq.m)
required physically filling up holes, implementation of spurs, and putting into place artificial
concrete structures to promote the natural colonization of corals and other reef organisms in
order to reduce swell impacts. The creation of a coral reef garden was also part of the project
with the transplantation of corals collected in the vicinity. Fifty groups of three different types
of concrete blocks have been set out on the site and six others constitute the coral reef garden
on which 311 coral colonies are transplanted.
Two and a half years after this restoration, the project proved to be successful. The coral
reef garden flourished; it showed much diversification and little mortality among the corals
colonies, and the natural colonization on the concrete substrate was teeming with corals, seaurchins,
mollusks, and fishes. But thirty months later, an exceptionally violent meteorological
and oceanographical situation led to a catastrophic event which caused many transplanted
coral as weil as natural colonies in the vicinity to be killed off. Lagoon waters temperatures
were recorded as high as 34°C and of the 311 transplanted coral colonies only 119 survived,
most of them bleached or partly dead. All colonies of the genus Acropora died, while those of
the genus Psammocora survived.
Methods for restoration and creation of coral reef gardens are highly controlled but they
cannot always escape such catastrophic events such as the one in Bora Bora in December 2001. Physical restoration was successful but the biological transplantation of corals failed.
Thus, when we consider how expansive a restoration project is, it is essential to conduct an
historical inquiry on a potential coral transplantation site before implementing any projectLes problĂšmes de restauration de zones coralliennes, avec transplantations de coraux,
sont à l'ordre du jour compte tenu de la dégradation accélérée de cet écosystÚme à la surface
de la planĂšte. Les motivations des recherches dans ce domaine et celles des projets de restauration
sur le terrain sont évoquées. Elles répondent à une demande sociale exprimée en fonction
de considérations culturelles et économiques. Les projets sont coûteux et ne peuvent concerner
que des cas trĂšs limitĂ©s avec des intĂ©rĂȘts Ă©conomiques importants (lutte contre
l' érosion, développement du tourisme).
à Bora Bora, en Polynésie française, une zone lagonaire frangeante, dégradée par des
extractions de sédiment corallien, provoquait une érosion littorale. Son ré-aménagement comporte
une restauration physique des lieux (comblement des fosses, réalisation d'épis...) et la
mise en place de structures artificielles pour permettre la colonisation naturelle de coraux et
autres organismes, afin de jouer le rÎle de brise houle. Ce projet s'accompagne de la création
d'un jardin corallien avec structures artificielles sur lesquelles sont fixés des transplants de
coraux. Deux ans et demi aprÚs la fin des travaux, le jardin corallien affiche une communauté
corallienne florissante et diversifiée avec trÚs peu de mortalité des colonies transplantées, une
croissance normale et la colonisation naturelle de coraux et d'autres organismes des récifs
coralliens (oursins, mollusques, poissons). Cependant, un événement météorologique et océanographique
exceptionnel, trente mois aprÚs la création du jardin corallien, a entraßné une
forte mortalité des coraux transplantés comme ceux naturellement en place dans le secteur. Si
les techniques nécessaires à la restauration de zones dégradées et à la création de jardins
coralliens sont totalement maßtrisées, ces réalisations n'échappent pas aux variations temporelles
des conditions de milieu qui peuvent ĂȘtre catastrophiques. Dans un tel cas, comme Ă
Bora Bora en décembre 2001, la restauration physique reste à l'actif de l'opération, mais
l'échec de la restauration biologique est à noter. Une étude historique, sur plusieurs décennies,
des zones sujettes à des mortalités exceptionnelles s'impose donc avant tout choix de
sites pour la réalisation de jardins coralliens dont les coûts sont trÚs élevé
Peripheral Delta Opioid Receptors Mediate Formoterol Anti-allodynic Effect in a Mouse Model of Neuropathic Pain.
Neuropathic pain is a challenging condition for which current therapies often remain unsatisfactory. Chronic administration of ÎČ2 adrenergic agonists, including formoterol currently used to treat asthma and chronic obstructive pulmonary disease, alleviates mechanical allodynia in the sciatic nerve cuff model of neuropathic pain. The limited clinical data currently available also suggest that formoterol would be a suitable candidate for drug repurposing. The antiallodynic action of ÎČ2 adrenergic agonists is known to require activation of the delta-opioid (DOP) receptor but better knowledge of the molecular mechanisms involved is necessary. Using a mouse line in which DOP receptors were selectively ablated in neurons expressing Nav1.8 sodium channels (DOP cKO), we showed that these DOP peripheral receptors were necessary for the antiallodynic action of the ÎČ2 adrenergic agonist formoterol in the cuff model. Using a knock-in mouse line expressing a fluorescent version of the DOP receptor fused with the enhanced green fluorescent protein (DOPeGFP), we established in a previous study, that mechanical allodynia is associated with a smaller percentage of DOPeGFP positive small peptidergic sensory neurons in dorsal root ganglia (DRG), with a reduced density of DOPeGFP positive free nerve endings in the skin and with increased DOPeGFP expression at the cell surface. Here, we showed that the density of DOPeGFP positive free nerve endings in the skin is partially restored and no increase in DOPeGFP translocation to the plasma membrane is observed in mice in which mechanical pain is alleviated upon chronic oral administration of formoterol. This study, therefore, extends our previous results by confirming that changes in the mechanical threshold are associated with changes in peripheral DOP profile. It also highlights the common impact on DOP receptors between serotonin noradrenaline reuptake inhibitors such as duloxetine and the ÎČ2 mimetic formoterol.journal article20192020 02 14importe
The antiallodynic action of pregabalin in neuropathic pain is independent from the opioid system.
BACKGROUND: Clinical management of neuropathic pain, which is pain arising as a consequence of a lesion or a disease affecting the somatosensory system, partly relies on the use of anticonvulsant drugs such as gabapentinoids. Therapeutic action of gabapentinoids such as gabapentin and pregabalin, which act by the inhibition of calcium currents through interaction with the α2Ύ-1 subunit of voltage-dependent calcium channels, is well documented. However, some aspects of the downstream mechanisms are still to be uncovered. Using behavioral, genetic, and pharmacological approaches, we tested whether opioid receptors are necessary for the antiallodynic action of acute and/or long-term pregabalin treatment in the specific context of neuropathic pain.
RESULTS: Using the cuff model of neuropathic pain in mice, we show that acute pregabalin administration at high dose has a transitory antiallodynic action, while prolonged oral pregabalin treatment leads to sustained antiallodynic action, consistent with clinical observations. We show that pregabalin remains fully effective in ÎŒ-opioid receptor, in ÎŽ-opioid receptor and in Îș-opioid receptor deficient mice, either female or male, and its antiallodynic action is not affected by acute naloxone. Our work also shows that long-term pregabalin treatment suppresses tumor necrosis factor-α overproduction induced by sciatic nerve constriction in the lumbar dorsal root ganglia.
CONCLUSIONS: We demonstrate that neither acute nor long-term antiallodynic effect of pregabalin in a context of neuropathic pain is mediated by the endogenous opioid system, which differs from opioid treatment of pain and antidepressant treatment of neuropathic pain. Our data are also supportive of an impact of gabapentinoid treatment on the neuroimmune aspect of neuropathic pain.journal articleresearch support, non-u.s. gov't20162016 03 29importe
Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTICâHF: baseline characteristics and comparison with contemporary clinical trials
Aims:
The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTICâHF) trial. Here we describe the baseline characteristics of participants in GALACTICâHF and how these compare with other contemporary trials.
Methods and Results:
Adults with established HFrEF, New York Heart Association functional class (NYHA)ââ„âII, EF â€35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokineticâguided dosing: 25, 37.5 or 50âmg bid). 8256 patients [male (79%), nonâwhite (22%), mean age 65âyears] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NTâproBNP 1971âpg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTICâHF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressureâ<â100âmmHg (n = 1127), estimated glomerular filtration rate <â30âmL/min/1.73 m2 (n = 528), and treated with sacubitrilâvalsartan at baseline (n = 1594).
Conclusions:
GALACTICâHF enrolled a wellâtreated, highârisk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation
Le traité des couleurs de Barthélemi L'Anglais (XIIIes)
Le xixe livre du De proprietatibus rerum rassemble les compilations de Barthélemi l'Anglais sur les couleurs, les odeurs, les saveurs et les liquides. Les trente-sept premiers chapitres sont donc un "traité des couleurs", que nous avons choisi de présenter dans la traduction achevée en 1372 par Jean Corbechon, chapelain de Charles V. Ce traité se compose, conformément au plan général adopté par Barthélemi, de deux grandes parties. Dans la premiÚre, il "parle" des couleurs en général, dans la ..
La présentation du Diable par un encyclopédiste du xiiie siÚcle : Bartelemi l'Anglais (vers 1250)
Si tout au long du Moyen Age le prestige des savants fut reconnu, leur influence sur leurs contemporains resta relativement restreinte. En effet, pour Ă©clatants qu'aient Ă©tĂ© certains foyers d'Ă©tude, ils restĂšrent longtemps dispersĂ©s et mobiles au grĂ© des circonstances. De mĂȘme, le rayonnement des maĂźtres se dĂ©plaçait avec eux. Au xiiie siĂšcle, et notamment en France, une certaine stabilisation politique et Ă©conomique permit une fixation et des centralisations de la vie universitaire. Rappelon..
Barthelemi lâAnglais, traitĂ©s du soleil et de la lune, traduits par Jean Corbechon (1372) (Ă©dition et commentaire)
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La Tunisie et ses relations avec La Catalogne de 1229 Ă 1315 : Extrait de : Armand LLINARĂS, Ramon Llull, Edicions 62, Barcelona, 1987, pp 22-31
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