INTRODUCING CORE-SHELL TECHNOLOGY FOR CONFORMANCE CONTROL

Reservoir heterogeneities can severely affect the effectiveness of waterflooding because displacing fluids tend to flow along high-permeability paths and prematurely breakthrough at producing wells. A Proof-of-Concept (PoC) study is presented while discussing the experimental results of a research on "core-shell" technology to improve waterflooding in heterogeneous oil reservoirs. The proposed methodology consists in injecting a water dispersion of nanocapsules after the reservoir has been extensively flushed with water. The nanocapsules are made of a "core" (either polymeric or siliceous materials), protected by a "shell" that can release its content at an appropriate time, which activates through gelation or aggregation thus plugging the high permeability paths. Additional flooding with water provides recovery of bypassed oil. The initial conceptual screening of possible materials was followed by extensive batch and column lab tests. Then, 3D dynamic simulations at reservoir scale were performed to compensate for the temporary lack of pilot tests and/or field applications

The D-amino acid oxidase-carbon nanotubes: evaluation of cytotoxicity and biocompatibility of a potential anticancer nanosystem

The ‘enzyme prodrug therapy’ represents a promising strategy to overcome limitations of current cancer treatments by the systemic administration of prodrugs, converted by a foreign enzyme into an active anticancer compound directly in tumor sites. One example is D-amino acid oxidase (DAAO), a dimeric favoenzyme able to catalyze the oxidative deamination of D-amino acids with production of hydrogen peroxide, a reactive oxygen species (ROS), able to favor cancer cells death. A DAAO variant containing fve aminoacidic substitutions (mDAAO) was demonstrated to possess a better therapeutic efcacy under low O2 concentration than wild-type DAAO (wtDAAO). Recently, aiming to design promising nanocarriers for DAAO, multi-walled carbon nanotubes (MWCNTs) were functionalized with polyethylene glycol (PEG) to reduce their tendency to aggregation and to improve their biocompatibility. Here, wtDAAO and mDAAO were adsorbed on PEGylated MWCNTs and their activity and cytotoxicity were tested. While PEG-MWCNTs-DAAOs have shown a higher activity than pristine MWCNTs-DAAO (independently on the DAAO variant used), PEG-MWCNTs-mDAAO showed a higher cytotoxicity than PEG-MWCNTs-wtDAAO at low O2 concentration. In order to evaluate the nanocarriers’ biocompatibility, PEG-MWCNTsDAAOs were incubated in human serum and the composition of protein corona was investigated via nLC-MS/MS, aiming to characterize both soft and hard coronas. The mDAAO variant has infuenced the bio-corona composition in both number of proteins and presence of opsonins and dysopsonins: notably, the soft corona of PEG-MWCNTs-mDAAO contained less proteins and was more enriched in proteins able to inhibit the immune response than PEG-MWCNTs-wtDAAO. Considering the obtained results, the PEGylated MWCNTs conjugated with the mDAAO variant seems a promising candidate for a selective antitumor oxidative therapy: under anoxic-like conditions, this novel drug delivery system showed a remarkable cytotoxic efect controlled by the substrate addition, against diferent tumor cell lines, and a bio-corona composition devoted to prolong its blood circulation time, thus improving the drug’s biodistribution

Atténuer les symptômes moteurs et améliorer la qualité de vie des patients atteints de la maladie de Parlinson âgés de 65 à 79 ans: une revue de littérature des interventions mobilisables par les infirmières

En Suisse, plus de 15’000 personnes sont touchées par la maladie de Parkinson (Parkinson Suisse, 2017). Selon Defebvre (2007), cette dernière débute chez des personnes âgées entre 58 et 62 ans. Cette pathologie chronique provoque des déficiences motrices qui induisent une diminution de la qualité de vie (Rafferty et al., 2017). Ces troubles moteurs ont également de nombreux impacts sur les personnes dans leur vie quotidienne au domicile et leurs nombreuses conséquences négatives pourraient favoriser l’institutionnalisation, une finalité redoutée par la personne âgée (Barthe, Clément & Drulhe, 1990). Dès lors, pouvoir atténuer les symptômes négatifs de la maladie de Parkinson, retarder une quelconque institutionnalisation et ainsi promouvoir la meilleure qualité de vie possible pour ces patients sont des objectifs essentiels. Différentes interventions centrées sur le patient telles que la thérapie aquatique, l’exercice au tapis roulant ainsi que la danse peuvent leur être proposés pour atténuer les troubles moteurs et ainsi améliorer leur qualité de vie

PRENYLATED CURCUMIN ANALOGUES AS MULTIPOTENT TOOLS TO TACKLE ALZHEIMER'S DISEASE

Alzheimer's disease is likely to be caused by copathogenic factors including aggregation of A\u3b2 peptides into oligomers and fibrils, neuroinflammation and oxidative stress. To date, no effective treatments are available and because of the multifactorial nature of the disease, it emerges the need to act on different and simultaneous fronts. Despite the multiple biological activities ascribed to curcumin as neuroprotector, its poor bioavailability and toxicity limit the success in clinical outcomes. To tackle Alzheimer's disease on these aspects, the curcumin template was suitably modified and a small set of analogues was attained. In particular, derivative 1 turned out to be less toxic than curcumin. As evidenced by capillary electrophoresis and transmission electron microscopy studies, 1 proved to inhibit the formation of large toxic A\u3b2 oligomers, by shifting the equilibrium towards smaller non-toxic assemblies and to limit the formation of insoluble fibrils. These findings were supported by molecular docking and steered molecular dynamics simulations which confirmed the superior capacity of 1 to bind A\u3b2 structures of different complexity. Remarkably, 1 also showed in vitro anti-inflammatory and anti-oxidant properties. In summary, the curcumin-based analogue 1 emerged as multipotent compound worth to be further investigated and exploited in the Alzheimer's disease multi-target context

Neuroanatomy of the grey seal brain : bringing pinnipeds into the neurobiological study of vocal learning

N.H. is supported by funding from an International Max Planck Research School (IMPRS) for language sciences fellowship grant, and the work of N.H. and S.C.V. was supported by a Max Planck Research Group (MPRG) awarded to S.C.V. The work of L.V. and A.R. was supported by a Max Planck Research Group (MPRG) awarded to A.R. S.C.V. was also supported by a Human Frontiers Science Program (HFSP) Research grant (grant no. RGP0058/2016) and a UKRI Future Leaders Fellowship (grant no. MR/T021985/1).Comparative animal studies of complex behavioural traits, and their neurobiological underpinnings, can increase our understanding of their evolution, including in humans. Vocal learning, a potential precursor to human speech, is one such trait. Mammalian vocal learning is under-studied: most research has either focused on vocal learning in songbirds or its absence in non-human primates. Here, we focus on a highly promising model species for the neurobiology of vocal learning: grey seals (Halichoerus grypus). We provide a neuroanatomical atlas (based on dissected brain slices and magnetic resonance images), a labelled MRI template, a three-dimensional model with volumetric measurements of brain regions, and histological cortical stainings. Four main features of the grey seal brain stand out: (i) it is relatively big and highly convoluted; (ii) it hosts a relatively large temporal lobe and cerebellum; (iii) the cortex is similar to that of humans in thickness and shows the expected six-layered mammalian structure; (iv) there is expression of FoxP2 present in deeper layers of the cortex; FoxP2 is a gene involved in motor learning, vocal learning, and spoken language. Our results could facilitate future studies targeting the neural and genetic underpinnings of mammalian vocal learning, thus bridging the research gap from songbirds to humans and non-human primates. Our findings are relevant not only to vocal learning research but also to the study of mammalian neurobiology and cognition more in general.PostprintPeer reviewe

Heparin Strongly Enhances the Formation of β2-Microglobulin Amyloid Fibrils in the Presence of Type I Collagen

The tissue specificity of fibrillar deposition in dialysis-related amyloidosis is most likely associated with the peculiar interaction of beta2-microglobulin (beta2-m) with collagen fibers. However, other co-factors such as glycosaminoglycans might facilitate amyloid formation. In this study we have investigated the role of heparin in the process of collagen-driven amyloidogenesis. In fact, heparin is a well known positive effector of fibrillogenesis, and the elucidation of its potential effect in this type of amyloidosis is particularly relevant because heparin is regularly given to patients subject to hemodialysis to prevent blood clotting. We have monitored by atomic force microscopy the formation of beta2-m amyloid fibrils in the presence of collagen fibers, and we have discovered that heparin strongly accelerates amyloid deposition. The mechanism of this effect is still largely unexplained. Using dynamic light scattering, we have found that heparin promotes beta2-m aggregation in solution at pH 6.4. Morphology and structure of fibrils obtained in the presence of collagen and heparin are highly similar to those of natural fibrils. The fibril surface topology, investigated by limited proteolysis, suggests that the general assembly of amyloid fibrils grown under these conditions and in vitro at low pH is similar. The exposure of these fibrils to trypsin generates a cleavage at the C-terminal of lysine 6 and creates the 7-99 truncated form of beta2-m (DeltaN6beta2-m) that is a ubiquitous constituent of the natural beta2-m fibrils. The formation of this beta2-m species, which has a strong propensity to aggregate, might play an important role in the acceleration of local amyloid deposition

Restrictive Cardiomyopathy, Atrioventricular Block and Mild to Subclinical Myopathy in Patients With Desmin-Immunoreactive Material Deposits

AbstractObjectives. We present clinical data and heart and skeletal muscle biopsy findings from a series of patients with ultrastructural accumulations of granulofilamentous material identified as desmin.Background. Desmin cardiomyopathy is a poorly understood disease characterized by abnormal desmin deposits in cardiac and skeletal muscle.Methods. Clinical evaluation, endomyocardial and skeletal muscle biopsy, light and electron microscopy and immunohistochemistry were used to establish the presence of desmin cardiomyopathy.Results. Six hundred thirty-one patients with primary cardiomyopathy underwent endomyocardial biopsy (EMB). Ultrastructural accumulations of granulofilamentous material were found in 5 of 12 biopsy samples from patients with idiopathic restrictive cardiomyopathy and demonstrated specific immunoreactivity with anti-desmin antibodies by immunoelectron microscopy. Immunohistochemical findings on light microscopy were nonspecific because of a diffuse intracellular distribution of desmin. All five patients had atrioventricular (AV) block and mild or subclinical myopathy. Granulofilamentous material was present in skeletal muscle biopsy samples in all five patients, and unlike the heart biopsy samples, light microscopic immunohistochemical analysis demonstrated characteristic subsarcolemmal desmin deposits. Two patients were first-degree relatives (mother and son); another son with first-degree AV block but without myopathy or cardiomyopathy demonstrated similar light and ultrastructural findings in skeletal muscle. Electrophoretic studies demonstrated two isoforms of desmin—one of normal and another of lower molecular weight—in cardiac and skeletal muscle of the familial cases.Conclusions. Desmin cardiomyopathy must be considered in the differential diagnosis of restrictive cardiomyopathy, especially in patients with AV block and myopathy. Diagnosis depends on ultrastructural examination of EMB samples or light microscopic immunohistochemical studies of skeletal muscle biopsy samples. Familial desminopathy may manifest as subclinical disease and may be associated with abnormal isoforms of desmin

INTRODUCING CORE-SHELL TECHNOLOGY FOR CONFORMANCE CONTROL

Reservoir heterogeneities can severely affect the effectiveness of waterflooding because displacing fluids tend to flow along high-permeability paths and prematurely breakthrough at producing wells. A Proof-of-Concept (PoC) study is presented while discussing the experimental results of a research on “core-shell” technology to improve waterflooding in heterogeneous oil reservoirs. The proposed methodology consists in injecting a water dispersion of nanocapsules after the reservoir has been extensively flushed with water. The nanocapsules are made of a “core” (either polymeric or siliceous materials), protected by a “shell” that can release its content at an appropriate time, which activates through gelation or aggregation thus plugging the high permeability paths. Additional flooding with water provides recovery of bypassed oil. The initial conceptual screening of possible materials was followed by extensive batch and column lab tests. Then, 3D dynamic simulations at reservoir scale were performed to compensate for the temporary lack of pilot tests and/or field applications

Theory as a driving force to understand reactions on nanoparticles: general discussion

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