Status and perspectives of the 4 pi charged particles multidetector CHIMERA

The construction of the multidetector CHIMERA designed to detect and identify charged particles and fragments emitted in heavy ion reactions at intermediate energy is in progress and is coming to an end. The construction of this multidetector is presented in this paper as well as the status of the project

Collagen functionalisation by plasma coupled to chemical grafting

The promising trends in biotechnology and tissue engineering are based on the development of advanced materials with biomimetic features in order to recreate the native environment promoting the appropriate cell behavior for tissue regeneration. Cell therapy together with novel functionalized biomaterials represent a very promising approach in regenerative medicine for cartilage regeneration. Articular cartilage exhibits a well-ordered organization with an extracellular matrix arranged as a network of collagen fibers and proteoglycans that allow for cell adhesion, mechanical support, transduction of chemical and mechanical signals from the surrounding tissue to the cells. Electrospun materials are considered highly promising scaffolds for cartilage tissue engineering given their specific fibrous morphology that resembles the fibrous component of tissue extracellular matrix. Many synthetic and natural polymers have been successfully electrospun to obtain scaffolds. Among natural polymers, collagen is universally applied as biomaterial in regenerative medicine because of its unique biocompatibility, and structural property. Robust techniques for surface \u201cbiodecoration\u201d are currently required and the appropriate surface functionalization still remains a critical variable for the optimal performance of a wide range of biomaterials. Covalent bonding of bioactive molecules to material surface is a valid strategy in order to allow a sufficiently strong and specific affinity of biomolecules with the surface itself; in addition covalent bonding may permit site-directed immobilization and preservation of specific conformation and exposition to control biological responses. Plasma processes allow to tune surface properties of materials with negligible effect on their bulk. The need of improving cell/surface interaction has decisively introduced plasma techniques in the field of biomaterials; In addition, a wide range of compounds can be chosen as a monomer for plasma polymerization, providing a great diversity of possible surface modifications with different functional groups, including amine, anhydride, epoxide, carboxylic acid, cyano, halide, hydroxyl, furfuryl, and perfluoroalkyl

Hydractinia allodeterminant alr1 resides in an immunoglobulin superfamily-like gene complex

Allorecognition, the ability to discriminate between self and nonself, is ubiquitous among colonial metazoans and widespread among aclonal taxa [1-3]. Genetic models for the study of allorecognition have been developed in the jawed vertebrates [4], invertebrate chordate Botryllus [5, 6], and cnidarian Hydractinia [7]. In Botryllus, two genes contribute to the histocompatibility response, FuHC [5, 8] and fester [6]. In the cnidarian Hydractinia, one of the two known allorecognition loci, alr2, has been isolated [7], and a second linked locus, alr1, has been mapped to the same chromosomal region, called the allorecognition complex (ARC) [9, 10]. Here we isolate alr1 by positional cloning and report it to encode a transmembrane receptor protein with two hypervariable extracellular regions similar to immunoglobulin (Ig)-like domains. Variation in the extracellular domain largely predicts fusibility within and between laboratory strains and wild-type isolates. alr1 was found embedded in a family of immunoglobulin superfamily (IgSF)-like genes, thus establishing that the ARC histocompatibility complex is an invertebrate IgSF-like gene complex. © 2010 Elsevier Ltd. All rights reserved.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Hydractinia allodeterminant alr1 resides in an immunoglobulin superfamily-like gene complex

Allorecognition, the ability to discriminate between self and nonself, is ubiquitous among colonial metazoans and widespread among aclonal taxa [1-3]. Genetic models for the study of allorecognition have been developed in the jawed vertebrates [4], invertebrate chordate Botryllus [5, 6], and cnidarian Hydractinia [7]. In Botryllus, two genes contribute to the histocompatibility response, FuHC [5, 8] and fester [6]. In the cnidarian Hydractinia, one of the two known allorecognition loci, alr2, has been isolated [7], and a second linked locus, alr1, has been mapped to the same chromosomal region, called the allorecognition complex (ARC) [9, 10]. Here we isolate alr1 by positional cloning and report it to encode a transmembrane receptor protein with two hypervariable extracellular regions similar to immunoglobulin (Ig)-like domains. Variation in the extracellular domain largely predicts fusibility within and between laboratory strains and wild-type isolates. alr1 was found embedded in a family of immunoglobulin superfamily (IgSF)-like genes, thus establishing that the ARC histocompatibility complex is an invertebrate IgSF-like gene complex. © 2010 Elsevier Ltd. All rights reserved.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

DNA methylation of shelf, shore and open sea CpG positions distinguish high microsatellite instability from low or stable microsatellite status colon cancer stem cells

Aim: To investigate the genome-wide methylation of genetically characterized colorectal cancer stem cell (CR-CSC) lines. Materials & methods: Eight CR-CSC lines were isolated from primary colorectal cancer (CRC) tissues, cultured and characterized for aneuploidy, mutational status of CRC-related genes and microsatellite instability (MSI). Genome-wide DNA methylation was assessed by MethylationEPIC microarray. Results: We describe a distinctive methylation pattern that is maintained following in vivo passages in immune-compromised mice. We identified an epigenetic CR-CSC signature associated with MSI. We noticed that the preponderance of the differentially methylated positions do not reside at CpG islands, but spread to shelf and open sea regions. Conclusion: Given that CRCs with MSI-high status have a lower metastatic potential, the identification of a MSI-related methylation signature could provide new insights and possible targets into metastatic CRC

Wildfire changes the spatial pattern of soil nutrient availability in Pinus canariensis forests

Soil resources are heterogeneously distributed in terrestrial plant communities. This heterogeneity is important because it determines the availability of local soil resources. A forest fire may change the spatial distribution of soil nutrients, affecting nutrition and survival of colonizing plants. However, specific information on the effects of ecosystem disturbance on the spatial distribution of soil resources is scarce. We hypothesized that, on a short-term basis, wildfire would change the spatial patterns of soil N and P availability. To test this hypothesis, we selected two Pinus canariensis forests burned in 2005 and 2000, respectively, and a third forest that was unburned since at least 1990 (unburned). We incubated ionic exchange membranes (IEMs) in replicated plots to estimate soil N and P availability and characterized the spatial pattern using SADIE (Spatial Analysis by Distance Indices). Mineral N, NO3-N and PO4-P availability, and aggregation and cluster indices for all nutrients were higher in the 2005 wildfire plots than in the 2000 wildfire and unburned plots. Our results suggest that surviving plants or new individuals becoming established in a burned area would find higher soil resources, but also higher small-scale heterogeneity in nutrients, which may have a major impact on the performance of individual plants and on the forest structure and dynamics.Ministerio de Ciencia y Tecnologí

Particle identification method in the CsI(Tl) scintillator used for the CHIMERA 4π\pi detector

The charged particle identification obtained by the analysis of signals coming from the CsI(Tl) detectors of the CHIMERA 4 heavy-ion detector is presented. A simple double-gate integration method, with the use of the cyclotron radiofrequency as reference time, results in low thresholds for isotopic particle identification. The dependence of the identification quality on the gate generation timing is discussed. Isotopic identification of light ions up to Beryllium is clearly seen. For the first time also the identification of Z=5 particles is observed. The identification of neutrons interacting with CsI(Tl) by (n, ) and (n,) reactions is also discussed

Particle identification method in the CsI(Tl) scintillator used for the CHIMERA 4π\pi detector

The charged particle identification obtained by the analysis of signals coming from the CsI(Tl) detectors of the CHIMERA 4 heavy-ion detector is presented. A simple double-gate integration method, with the use of the cyclotron radiofrequency as reference time, results in low thresholds for isotopic particle identification. The dependence of the identification quality on the gate generation timing is discussed. Isotopic identification of light ions up to Beryllium is clearly seen. For the first time also the identification of Z=5 particles is observed. The identification of neutrons interacting with CsI(Tl) by (n, ) and (n,) reactions is also discussed