Detection of small murine lung tumours by FDG-PET

[Abstract] AMI International Conference 2003, September 21 - 27, Madrid, Spain: "High Resolution Molecular Imaging: from Basic Science to Clinical Applications"The functional information provided by 2-deoxy-2- [18F]fluoro-D-Glucose (FDG) positron emission tomography (PET) is commonly used to detect primary tumours and metastases in clinical studies. The aim of this work is to assess the possibilities of FDG-PET studies to detect small lung tumour lesions in mice, using a dedicated small animal PET scannerPublicad

Trebouxia lynnae sp. nov. (former Trebouxia sp. TR9): biology and biogeography of an epitome lichen symbiotic microalga

Two microalgal species, Trebouxia jamesii and Trebouxia sp. TR9, were detected as the main photobionts coexisting in the thalli of the lichen Ramalina farinacea. Trebouxia sp. TR9 emerged as anew taxon in lichen symbioses and was successfully isolated and propagated in in vitro culture andthoroughly investigated. Several years of research have confirmed the taxon Trebouxia sp. TR9 tobe a model/reference organism for studying mycobiont–photobiont association patterns in lichensymbioses. Trebouxia sp. TR9 is the first symbiotic, lichen-forming microalga for which an exhaustivecharacterization of cellular ultrastructure, physiological traits, genetic and genomic diversity is available.The cellular ultrastructure was studied by light, electron and confocal microscopy; physiologicaltraits were studied as responses to different abiotic stresses. The genetic diversity was previouslyanalyzed at both the nuclear and organelle levels by using chloroplast, mitochondrial, and nucleargenome data, and a multiplicity of phylogenetic analyses were carried out to study its intraspecificdiversity at a biogeographical level and its specificity association patterns with the mycobiont.Here, Trebouxia sp. TR9 is formally described by applying an integrative taxonomic approach and ispresented to science as Trebouxia lynnae, in honor of Lynn Margulis, who was the primary modernproponent for the significance of symbiosis in evolution. The complete set of analyses that werecarried out for its characterization is provided

Effects of MDMA on blood glucose levels and brain glucose metabolism

Purpose This study was designed to assess changes in glucose metabolism in rats administered single or repeated doses of MDMA. Methods Two different experiments were performed: (1) A single-dose study with four groups receiving 20 mg/kg, 40 mg/kg, saline or heat, and (2) a repeated-dose study with two groups receiving three doses, at intervals of 2 h, of 5 mg/kg or saline. Rats were imaged using a dedicated small-animal PET scanner 1 h after single-dose administration or 7 days after repeated doses. Glucose metabolism was measured in 12 cerebral regions of interest. Rectal temperature and blood glucose were monitored. Results Peak body temperature was reached 1 h after MDMA administration. Blood glucose levels decreased significantly after MDMA administration. In the single-dose experiment, brain glucose metabolism showed hyperactivation in cerebellum and hypo-activation in the hippocampus, amygdala and auditory cortex. In the repeated-dose experiment, brain glucose metabolism did not show any significant change at day 7. Conclusion These results are the first to indicate that MDMA has the potential to produce significant hypoglycaemia. In addition, they show that MDMA alters glucose metabolism in components of the motor, limbic and somatosensory systems acutely but not on a long-term basisPublicad

Research at the medical imaging laboratory, CIBERSAM CB07/09/0031

The Medical Imaging Laboratory is a research group within the Hospital General Universitario Gregorio Marañón. The main research line of the group is focused towards the development and exploitation of medical imaging techniques, including the development of new processing tools for image analysis in clinical and preclinical research. The group has a multi-disciplinary profile and a priority for translational research topics, derived from real problems faced by the clinical specialists. One of the main research areas is the development of technologies for molecular imaging, some of which have been transferred to the industry and are now among the top products of the market. These systems include high-resolution PET, CT and PET-CT. Over the last years the group has developed several software tools to enable quantification of multimodal brain images using morphometric and functional data. Some research applications of these hardware and software tools are illustrated in the paper“Ministerio de Sanidad y Consumo”, CDTEAM Programa CÉNIT, Ministerio de Industria. FIS PI052271 “Ministerio de Sanidad y Consumo”. CIBER Salud Mental (CIBERSAM) “Ministerio de Sanidad y Consumo” and Fundación Mutua MadrileñaPublicad

Detection of rat brain activation using statistical parametric mapping analysis in FDG-PET studies

[Abstract] AMI International Conference 2003, September 21 - 27, Madrid, Spain: High Resolution Molecular Imaging: from Basic Science to Clinical ApplicationsStatistical parametric mapping (SPM) is an analysis technique long been used in clinical research to detect subtle activity changes in brain; it is an excellent exploratory tool as it does not require a priori assumptions about the expected brain region activations. Research in animal imaging may also take benefit from this technique, if properly adapted to the new scenario. This is the case of brain activation studies in murine models using PET tracers and dedicated imaging devices. This work proposes the use of an SPM methodology adapted to the analysis of 2-deoxy-2-[18F] fluoro-D-Glucose (FDG) positron emission tomography (PET) scans of rat brains. Advantages over conventional region of interest (ROI) based analysis were assessed in an experiment addressing the detection of brain activation in of rats which underwent three different visual stimulation paradigmsPublicad

Characterization in vitro and in vivo of a pandemic H1N1 influenza virus from a fatal case

Pandemic 2009 H1N1 (pH1N1) influenza viruses caused mild symptoms in most infected patients. However, a greater rate of severe disease was observed in healthy young adults and children without co-morbid conditions. Here we tested whether influenza strains displaying differential virulence could be present among circulating pH1N1 viruses. The biological properties and the genotype of viruses isolated from a patient showing mild disease (M) or from a fatal case (F), both without known co-morbid conditions were compared in vitro and in vivo. The F virus presented faster growth kinetics and stronger induction of cytokines than M virus in human alveolar lung epithelial cells. In the murine model in vivo, the F virus showed a stronger morbidity and mortality than M virus. Remarkably, a higher proportion of mice presenting infectious virus in the hearts, was found in F virus-infected animals. Altogether, the data indicate that strains of pH1N1 virus with enhanced pathogenicity circulated during the 2009 pandemic. In addition, examination of chemokine receptor 5 (CCR5) genotype, recently reported as involved in severe influenza virus disease, revealed that the F virus-infected patient was homozygous for the deleted form of CCR5 receptor (CCR5Δ32).Funding Statement: This work was supported by Instituto de Salud Carlos III (Programa especial de investigación sobre la gripe pándemica GR09/0023, GR09/0040, GR09/0039) and Ciber de Enfermedades Respiratorias. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.S

Molecular and Morphological Diversity of Trebouxia Microalgae in Sphaerothalliod Circinaria spp. Lichens

[EN] Three vagrant (Circinaria hispida, Circinaria gyrosa, Circinaria sp. `paramerae¿) and one crustose (semi-vagrant, Circinaria sp.`oromediterranea¿) growing in very continental areas in the Iberian Peninsula were selected to study the phycobiont diversity. Mycobiont identification was checked using nrITS DNA barcoding: Circinaria sp.`oromediterranea¿ and Circinaria sp. `paramerae¿ formed a new clade. Phycobiont diversity was analyzed in 50 thalli of Circinaria spp. using nrITS DNA and LSU rDNA, with microalgae coexistence being found in all the species analyzed by Sanger sequencing. The survey of phycobiont diversity showed up to four different Trebouxia spp. as the primary phycobiont in 20 thalli of C. hispida, in comparison with the remaining Circinaria spp. where only one Trebouxia was the primary microalga. In lichen species showing coexistence, some complementary approaches are needed (454 pyrosequencing and/or ultrastructural analyses). Five specimens were selected for HTS analyses: 22 Trebouxia OTUs were detected, ten of them not previously known. TEM analyses showed three different cell morphotypes (Trebouxia sp. OTU A12, OTU S51 and T. cretacea) whose ultrastructure is described here in detail for the first time, HTS revealed a different microalgae pool in each species studied, and we cannot assume a specific pattern between these pools and the ecological and/or morphological characteristics. The mechanisms involved in the selection of the primary phycobiont and the other microalgae by the mycobiont are unknown, and require complex experimental designs. The systematics of the genus Circinaria is not yet well resolved, and more analyses are needed to establish a precise delimitation of the species.Supported by the Ministerio de Economia y Competitividad (MINECO and FEDER, Spain; CGL2016-79158-P), Excellence in Research (Generalitat Valenciana, Spain; PROMETEO/2017/039). We want to thank the technicians (Ma Teresa Minguez and Nuria Cebrian) from the Servicio de Microscopia Electronica, SCSIE, and Jardi Botanic (Universitat de Valencia) who helped us to perform the TEM process, and Santiago Catala for the pyrosequencing analyses. Daniel Sheerin revised the English manuscript.Molins, A.; Moya, P.; García-Breijo, F.; Reig-Armiñana, J.; Barreno, E. (2018). Molecular and Morphological Diversity of Trebouxia Microalgae in Sphaerothalliod Circinaria spp. Lichens. Journal of Phycology. 54(4):494-504. https://doi.org/10.1111/jpy.12751S49450454

Premature stop codons in the G glycoprotein of human respiratory syncytial viruses resistant to neutralization by monoclonal antibodies.

Mutants of human respiratory syncytial (RS) virus which escaped neutralization by monoclonal antibodies directed against the G glycoprotein were selected from the Long strain. Most mutants showed drastic antigenic changes, reflected in the lack of reactivity with several anti-G antibodies, including the one used for selection. Sequence analysis revealed the presence of in-frame premature stop codons in the mutated G genes which shortened the G polypeptide by between 11 and 42 amino acids. In contrast, two mutants selected with monoclonal antibody 25G contained two amino acid substitutions (Phe-265----Leu and Leu-274----Pro) and had lost only the capacity to bind the antibody used in their selection. These results demonstrate that the carboxy-terminal end of the G molecule is dispensable for infectivity in tissue culture and indicate the importance of this part of the G protein in determining its antigenicity