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Biology subjects

Conte, C.

Publications and source records attributed to Conte, C..

4 recordsLinked to original sources

Metabolomics investigation of post-mortem human pericardial fluid

IntroductionDue to its peculiar anatomy and physiology, the pericardial fluid is a biological matrix of particular interest in the forensic field. Despite this, the available literature has mainly focused on post-mortem biochemistry and forensic toxicology, while to the best of authors knowledge post-mortem metabolomics has never been applied. Similarly, estimation of the time since death or Post-Mortem Interval based on pericardial fluids has still rarely been attempted. ObjectivesWe applied a metabolomic approach based on 1H Nuclear Magnetic Resonance Spectroscopy to ascertain the feasibility of monitoring post-mortem metabolite changes on human pericardial fluids with the aim of building a multivariate regression model for Post-Mortem Interval estimation. MethodsPericardial fluid samples were collected in 24 consecutive judicial autopsies, in a time frame ranging from 16 to 170 hours after death. The only exclusion criterion was the quantitative and/or qualitative alteration of the sample. Two different extraction protocols were applied for low molecular weight metabolites selection, namely ultrafiltration and liquid-liquid extraction. Our metabolomic approach was based on the use of 1H Nuclear Magnetic Resonance and multivariate statistical data analysis. ResultsThe pericardial fluid samples treated with the two experimental protocols did not show significant differences in the distribution of the metabolites detected. A post-mortem interval estimation model based on 18 pericardial fluid samples was validated with an independent set of 6 samples, giving a prediction error of 33 - 34 hours depending on the experimental protocol used. By narrowing the window to post-mortem intervals below 100 hours, the prediction power of the model was significantly improved with an error of 13-15 hours depending on the extraction protocol. Choline, glycine, ethanolamine, and hypoxanthine were the most relevant metabolites in the prediction model. ConclusionThe present study, although preliminary, shows that PF samples collected from a real forensic scenario represent a biofluid of interest for post-mortem metabolomics, with particular regard to the estimation of the time since death.

systems biology↗

Efficient simulation of 3D reaction-diffusion in models of neurons and networks

Neuronal activity is the result of both the electrophysiology and chemophysiology. A neuron can be well represented for the purposes of electrophysiological simulation as a tree composed of connected cylinders. This representation is also apt for 1D simulations of their chemophysiology, provided the spatial scale is larger than the diameter of the cylinders and there is radial symmetry. Higher dimensional simulation is necessary to accurately capture the dynamics when these criteria are not met, such as with wave curvature, spines, or diffusion near the soma. We have developed a solution to enable efficient finite volume method simulation of reaction-diffusion kinetics in intracellular 3D regions in neuron and network models and provide an implementation within the NEURON simulator. An accelerated version of the CTNG 3D reconstruction algorithm transforms morphologies suitable for ion-channel based simulations into consistent 3D voxelized regions. Kinetics are then solved using a parallel algorithm based on Douglas-Gunn that handles the irregular 3D geometry of a neuron; these kinetics are coupled to NEURONs 1D mechanisms for ion channels, synapses, etc. The 3D domain may cover the entire cell or selected regions of interest. Simulations with dendritic spines and of the soma reveal details of dynamics that would be missed in a pure 1D simulation. We describe and validate the methods and discuss their performance.

neuroscience↗

Wolbachia pipientis associated to tephritid fruit fly pests: from basic research to applications

Members of the true fruit flies (family Tephritidae) are among the most serious agricultural pests worldwide, whose control and management demands large and costly international efforts. The need for cost-effective and environmentally-friendly integrated pest management (IPM) has led to the development and implementation of autocidal control strategies. Autocidal approaches include the widely used sterile insect technique (SIT) and the incompatible insect technique (IIT). IIT relies on maternally transmitted bacteria (namely Wolbachia), to cause a conditional sterility in crosses between released mass-reared Wolbachia-infected males and wild females, which are either uninfected or infected with a different Wolbachia strain (i.e., cytoplasmic incompatibility; CI). Herein, we review the current state of knowledge on Wolbachia-tephritid interactions including infection prevalence in wild populations, phenotypic consequences, and their impact on life history traits. Numerous pest tephritid species are reported to harbor Wolbachia infections, with a subset exhibiting high prevalence. The phenotypic effects of Wolbachia have been assessed in very few tephritid species, due in part to the difficulty of manipulating Wolbachia infection (removal or transinfection). Based on recent methodological advances (high-throughput DNA sequencing) and a breakthrough concerning the mechanistic basis of CI, we suggest research avenues that could accelerate generation of necessary knowledge for the potential use of Wolbachia-based IIT in area-wide integrated pest management (AW-IPM) strategies for the population control of tephritid pests.

ecology↗

Spindly is Required for Rapid Migration of Human Cells.

Dynein is the sole minus-end directed microtubule motor found in animals. It has roles in cell division, membrane trafficking, and cell migration. Together with dynactin, dynein regulates centrosomal orientation to establish and maintain cell polarity, controls focal adhesion turnover and anchors microtubules at the leading edge. In higher eukaryotes, dynein/dynactin requires additional components such as Bicaudal D to form an active motor complex and for regulating its cellular localization. Spindly is a protein that targets dynein/dynactin to kinetochores in mitosis and can activate its motility in vitro. However, no role for Spindly in interphase dynein/dynactin function has been found. We show that Spindly binds to the cell cortex and microtubule tips and colocalizes with dynein/dynactin at the leading edge of migrating U2OS cells and primary fibroblasts. U2OS cells that lack Spindly migrated slower in 2D than control cells, although centrosome polarization appeared to happen properly in the absence of Spindly. Re-expression of Spindly rescues migration, but the expression of a mutant, which is defective for dynactin binding, failed to rescue this defect. Taken together, these data demonstrate that Spindly plays an important role in mediating a subset of dynein/dynactins function in cell migration.

cell biology↗