75 research outputs found
Using complementary techniques to distinguish cryptic species: A new Erysimum (Brassicaceae) species from North Africa
• Premise of the study : Cryptic species are superfi cially morphologically indistinguishable and therefore erroneously classifi ed under one single name. The identifi cation and delimitation of these species is usually a diffi cult task. The main aim of this study is to provide an inclusive methodology that combines standard and new tools to allow accurate identifi cation of cryptic species. We used Erysimum nervosum s.l. as a model system. • Methods : Four populations belonging to E. nervosum s.l. were sampled at their two distribution ranges in Morocco (the Atlas Mountains and the Rif Mountains). Fifteen individuals per population were collected to assess standard taxonomic traits. Additionally, corolla color and shape were quantifi ed in 30 individuals per population using spectrophotometry and geometric morphometrics, respectively. Finally, we collected tissue samples from each population per species to study the phylogenetic relationships among them. • Key results : Using the standard taxonomic traits, we could not distinguish the four populations. Nonetheless, there were differences in corolla color and shape between plants from the two mountain ranges. The population differentiation based on quantitative morphological differences were confi rmed and supported by the phylogenetic relationships obtained for these populations and the rest of the Moroccan Erysimum species. • Conclusions : The joint use of the results obtained from standard taxonomic traits, quantitative analyses of plant phenotype, and molecular data suggests the occurrence of two species within E. nervosum s.l. in Morocco, one located in the Atlas Mountains ( E. nervosum s.s.) and the other in the Rif Mountains ( E. riphaeanum sp. nov.). Consequently, we suggest that combining quantitative and molecular approaches with standard taxonomy greatly benefi ts the identifi cation of cryptic species
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Conservation assessments and Red Listing of the endemic Moroccan flora (monocotyledons)
Morocco constitutes an important centre of plant diversity and speciation in the Mediterranean Basin. However, numerous species are threatened by issues ranging from human activities to global climatic change. In this study,
we present the conservation assessments and Red Listing of the endemic Moroccan monocotyledons according to
International Union for Conservation of Nature (IUCN) criteria and categories. For each species, we include basic
taxonomic information, local names and synonyms, uses, a distribution map, extent of occurrence, area of
occupancy, population size and trend, a description of habitats and ecological requirements, and a discussion of the
threats affecting the species and habitats. We assessed the threatened status of the endemic Moroccan monocotyledons
at the species level (59 species) using the IUCN Red List criteria and categories (Version 3.1). This study
shows the high extinction risk to the Moroccan monocotyledon flora, with 95% of threatened species (20% Critically
Endangered, 50% Endangered, 25% Vulnerable) and only 5% not threatened (2% Near Threatened and 3% Least
Concern). The flora is thus of conservation concern, which is poorly recognized, both nationally and internationally.
The study presents the first part and so far the only national IUCN Red Data List for a large group of Moroccan
plants, and thus provides an overview of the threatened Moroccan flora. This IUCN Red List is an important first
step towards the recognition of the danger to Moroccan biodiversity hotspots, conservation of threatened species
and the raising of public awareness at national and international levels
Biological flora of Central europe: Baldellia ranunculoides (Alismataceae)
Baldellia ranunculoides (L.) Parl. (Alismataceae) is a taxonomically problematic aquatic plant with an historically ill-defined distribution and global conservation status. This paper finds morphological, ecological and molecular evidence for two distinct taxa, probably best described as subspecies: (1) B. ranunculoides subsp. ranunculoides and (2) B. ranunculoides subsp. repens and provides detailed distribution data on their overlapping range, in different habitats, across the cool, high rainfall areas of western Europe and west Mediterranean. The two subspecies are amongst the relatively large number of threatened European and north Africa aquatic plants and this paper provides a systematic review of their relative conservation pressures and management needs, with particular emphasis on the status of both taxa in central Europe. Other observations indicate probable evolutionary relationships within B. ranunculoides s.l. and its associated taxa and the review points out where these and other research topics could potentially be pursued
Vieux arbres remarquables du Maroc
Jahandiez Ămile. Vieux arbres remarquables du Maroc. In: La Terre et La Vie, Revue d'Histoire naturelle, tome 3, n°4, 1933. pp. 207-213
CaractĂšres botaniques des Acacia dealbata, decurrens et mollissima.
Jahandiez Ămile. CaractĂšres botaniques des Acacia dealbata, decurrens et mollissima.. In: Revue de botanique appliquĂ©e et d'agriculture coloniale, 4á” annĂ©e, bulletin n°31, 31 mars 1924. pp. 179-181
Therapeutic hypothermia and mitochondrial permeability transition in the post-cardiac arrest syndrome
LâarrĂȘt cardiaque (AC) est un problĂšme de santĂ© publique dont la mortalitĂ© reste trĂšs Ă©levĂ©e malgrĂ© les progrĂšs de la rĂ©animation. La majoritĂ© des dĂ©cĂšs Ă distance de la rĂ©animation cardio-pulmonaire (RCP) initiale est la consĂ©quence du syndrome postâAC provoquĂ© par les lĂ©sions cellulaires d'ischĂ©mie-reperfusion (I/R) qui touchent principalement le cĆur et le cerveau. Lâouverture du pore de transition de permĂ©abilitĂ© mitochondrial (PTP), en lien avec la cyclophiline D (CypD), est un dĂ©terminant majeur des lĂ©sions d'I/R. Lâhypothermie thĂ©rapeutique est le seul traitement adjuvant de la RCP qui a dĂ©montrĂ© un bĂ©nĂ©fice sur la survie des patients en limitant le syndrome post-AC. Ses mĂ©canismes dâaction complexes ne sont que partiellement compris. Dans ce travail de thĂšse, nous avons, dans un premier temps, utilisĂ© notre modĂšle d'AC chez le lapin pour Ă©tudier les mĂ©canismes mitochondriaux de lâhypothermie thĂ©rapeutique. Notre modĂšle a d'abord permis de mettre en Ă©vidence le rĂŽle important jouĂ© par la tempĂ©rature dans la gravitĂ© du syndrome postâAC et les effets protecteurs de lâhypothermie sur le cĆur et le cerveau. Notre travail montre Ă©galement que l'hypothermie inhibe lâouverture du PTP par un mĂ©canisme dĂ©pendant de la CypD et agit sur une voie de signalisation cellulaire. Nous avons, dans un second temps, mis au point un nouveau modĂšle d'AC chez la souris dĂ©ficiente en CypD montrant que l'inhibition complĂšte du mĂ©canisme dĂ©pendant de la CypD d'ouverture du PTP amĂ©liore le succĂšs de la RCP ainsi que le pronostic Ă long terme des animaux traitĂ©s par hypothermie thĂ©rapeutique. Ainsi, nos travaux contribuent Ă identifier les mĂ©canismes d'action mitochondriaux de lâhypothermie thĂ©rapeutique ainsi que des pistes pour amĂ©liorer le pronostic des patients aprĂšs un AC rĂ©animĂ©Despite advances in resuscitation science, mortality after cardiac arrest (CA) remains very high. A substantial proportion of cardiac arrest deaths occur in patients following successful resuscitation and can be attributed to the development of post-CA syndrome caused by cellular ischemia-reperfusion (I/R) injury that primarily affect heart and brain cells. The opening of the mitochondrial permeability transition pore (PTP), promoted by cyclophilin D (CypD), is a major determinant of I/R injuries. Therapeutic hypothermia is the only adjuvant therapy to cardiopulmonary resuscitation (CPR) known to improve survival by limiting the post-AC syndrome. The mechanisms of action of therapeutic hypothermia are still poorly understood. In this present work, we used our model of CA in rabbit to study the role of the PTP in the mechanisms of action of therapeutic hypothermia. Our model first highlighted the important role played by temperature in the severity of post-AC syndrome and the protective effects of hypothermia on heart and brain injuries. Our work also determined that hypothermia inhibited PTP opening by a CypD-dependent mechanism and acted on a pro-survival signaling pathway. We then developed a new CA model using CypD-deficient mice showing that complete inhibition of the CypD-dependent mechanism of PTP opening improved success of CPR and long-term survival of hypothermia-treated animals. Thus, our work contributes to identifying the mitochondrial mechanisms of action of therapeutic hypothermia and ways to improve the prognosis of patients after C
Hypothermie thĂ©rapeutique et transition de permĂ©abilitĂ© mitochondriale dans le syndrome post-arrĂȘt cardiaque
Despite advances in resuscitation science, mortality after cardiac arrest (CA) remains very high. A substantial proportion of cardiac arrest deaths occur in patients following successful resuscitation and can be attributed to the development of post-CA syndrome caused by cellular ischemia-reperfusion (I/R) injury that primarily affect heart and brain cells. The opening of the mitochondrial permeability transition pore (PTP), promoted by cyclophilin D (CypD), is a major determinant of I/R injuries. Therapeutic hypothermia is the only adjuvant therapy to cardiopulmonary resuscitation (CPR) known to improve survival by limiting the post-AC syndrome. The mechanisms of action of therapeutic hypothermia are still poorly understood. In this present work, we used our model of CA in rabbit to study the role of the PTP in the mechanisms of action of therapeutic hypothermia. Our model first highlighted the important role played by temperature in the severity of post-AC syndrome and the protective effects of hypothermia on heart and brain injuries. Our work also determined that hypothermia inhibited PTP opening by a CypD-dependent mechanism and acted on a pro-survival signaling pathway. We then developed a new CA model using CypD-deficient mice showing that complete inhibition of the CypD-dependent mechanism of PTP opening improved success of CPR and long-term survival of hypothermia-treated animals. Thus, our work contributes to identifying the mitochondrial mechanisms of action of therapeutic hypothermia and ways to improve the prognosis of patients after CALâarrĂȘt cardiaque (AC) est un problĂšme de santĂ© publique dont la mortalitĂ© reste trĂšs Ă©levĂ©e malgrĂ© les progrĂšs de la rĂ©animation. La majoritĂ© des dĂ©cĂšs Ă distance de la rĂ©animation cardio-pulmonaire (RCP) initiale est la consĂ©quence du syndrome postâAC provoquĂ© par les lĂ©sions cellulaires d'ischĂ©mie-reperfusion (I/R) qui touchent principalement le cĆur et le cerveau. Lâouverture du pore de transition de permĂ©abilitĂ© mitochondrial (PTP), en lien avec la cyclophiline D (CypD), est un dĂ©terminant majeur des lĂ©sions d'I/R. Lâhypothermie thĂ©rapeutique est le seul traitement adjuvant de la RCP qui a dĂ©montrĂ© un bĂ©nĂ©fice sur la survie des patients en limitant le syndrome post-AC. Ses mĂ©canismes dâaction complexes ne sont que partiellement compris. Dans ce travail de thĂšse, nous avons, dans un premier temps, utilisĂ© notre modĂšle d'AC chez le lapin pour Ă©tudier les mĂ©canismes mitochondriaux de lâhypothermie thĂ©rapeutique. Notre modĂšle a d'abord permis de mettre en Ă©vidence le rĂŽle important jouĂ© par la tempĂ©rature dans la gravitĂ© du syndrome postâAC et les effets protecteurs de lâhypothermie sur le cĆur et le cerveau. Notre travail montre Ă©galement que l'hypothermie inhibe lâouverture du PTP par un mĂ©canisme dĂ©pendant de la CypD et agit sur une voie de signalisation cellulaire. Nous avons, dans un second temps, mis au point un nouveau modĂšle d'AC chez la souris dĂ©ficiente en CypD montrant que l'inhibition complĂšte du mĂ©canisme dĂ©pendant de la CypD d'ouverture du PTP amĂ©liore le succĂšs de la RCP ainsi que le pronostic Ă long terme des animaux traitĂ©s par hypothermie thĂ©rapeutique. Ainsi, nos travaux contribuent Ă identifier les mĂ©canismes d'action mitochondriaux de lâhypothermie thĂ©rapeutique ainsi que des pistes pour amĂ©liorer le pronostic des patients aprĂšs un AC rĂ©anim
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