On the restoration of the last relict population of a dragonfly Urothemis edwardsii Selys (Libellulidae: Odonata) in the Mediterranean

The restoration of endangered relict populations is challenging in conservation biology because they require specific environmental conditions within an inhospitable regional climate. Urothemis edwardsii Selys is the most endangered dragonfly in the Mediterranean with only one known relict small population (Lac Bleu) left in Northeast Algeria. With the absence of successful (re-) colonization over the last two decades, the restoration of the species became a top priority. To improve the status of the species in Northeast Algeria, we carried out a reintroduction and translocation scheme during 2011–2015 and assessed the changes in distribution and population size. Our restoration plan led to the emergence of three populations of which one was restored (Lac Noir), one resulted from successful translocation (Lac Tonga Northeast), and one established after successful colonization (Lac Tonga Southwest). In three localities (Lac Noir, Lac Tonga Northeast, and Lac Tonga Southwest), signs of population growth were observed, whereas no significant trend in the source population (Lac Bleu) was detected. A new population (El Graeate) was also recorded in 2015, but its origin is uncertain. Capture-mark-recapture on adults conducted recapture rates and no sign of dispersal between the two sites. Dispersal capacity of the species and conservation implications of adult distribution are discussed. This study highlights the importance of using biological indicators in selecting host habitats for the restoration of critically threatened populations

Synaptosome Bioenergetics and Calcium Handling: Aging Response

Synaptic function and the role of mitochondria inside nerve terminals can be studied by the isolation of an enriched fraction of synaptosomes, which consist in nerve ending particles that are formed during homogenization of brain tissue. Different procedures have been described for the isolation of an enriched fraction of synaptosomes, most of them based on the use of gradients. Neuronal function seems to be critically dependent on the energy provided by mitochondrial respiration. The determination of bioenergetic parameters such as mitochondrial membrane potential, respiratory rates, ATP content and mitochondrial Ca2+ uptake in synaptosomal preparations can provide useful information to analyze the contribution of mitochondrial function to the efficiency of neurotransmission.Synaptic nerve terminals are constantly exposed to extensive Ca2+ fluxes. At the presynaptic terminal, the recovery from calcium oscillations critically depends on the proper mitochondrial function to generate ATP and buffer Ca2+ transients together with an efficient endoplasmic reticulum function.The differential characteristics of synaptic and non-synaptic mitochondria in terms of bioenergetics and free radical production, as well as the response to aging are discussed.Fil: Lores Arnaiz, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Rodriguez, Georgina Emma. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Biología Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de Biología Celular y Neurociencia; ArgentinaFil: Karadayian, Analia Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Bustamante, Juanita. Universidad Abierta Interamericana; Argentin

The Extracellular Matrix, Growth Factors and Morphogens in Biomaterial Design and Tissue Engineering

Cells, morphogens, growth factors, and custom scaffolds are the critical ingredients for successful tissue regeneration in which morphogens and growth factors function sequentially. Extensive studies, in vitro and in vivo, have been made to explore the mechanisms and the roles played by these molecules. As a consequence, precise, localized control over the signaling of these factors and appropriate strategy selection, depending on the tissue or organ to be repaired or regenerated, is known to permit specific management of regenerative processes. The first part of the chapter examines natural ECMs which are a set of molecules secreted by cells that provide structural and biochemical support to the surrounding cells. ECMs also perform many other functions, such as actively regulating cell function through the control of biochemical gradients, cell density, spatial organization, and ligand attachment, thus influencing various types of cell processes. Subsequently, growth factors and morphogens are examined in greater depth to clarify to what degree progress has been made into improving methodologies and functionality and, perhaps, to hint at what remains to be done for the future of tissue engineering