2,449 research outputs found

    Point Mutation I261M Affects the Dynamics of BVDV and its Interaction with Benzimidazole Antiviral 227G

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    Bovine viral diarrhea virus (BVDV) is a Pestivirus of the Flaviviridae family and represents a major viral pathogen in cattle and other ruminants. Infection with BVDV can result in a wide assortment of disease manifestations including resorption, mummification, or abortion of the dead fetus. Recently the point mutation I261M on the thumb domain was shown to confer resistance to BDVD against 227G and other benzimidazole compounds. Here we investigated the role of this mutation by using a multidisciplinary protocol, not involving free energy calculations on structures of the mutated complex which are taken a priori similar to those of the wild one. Namely, we firstly performed MD simulations on the wild and mutated BVDV RdRp proteins in aqueous solution. Then, we selected representative equilibrium conformations by performing a cluster analysis, and ran docking calculations of 277G on representative of the 5 most populated clusters of each protein. Finally, we performed MD simulation on selected complexes as to assess structural and dynamical differences between wild and mutated 227G-protein adducts. Interestingly, the mutation affects the structure and the dynamics of the protein, particularly in the region of binding of the ligand, and this results in a different binding site of 227G with respect to the wild protein. Moreover, while 227G closes the entrance to the RNA strand in the case of the wild protein, a gate and a channel leading to the catalytic site are still present in the mutated complex. These results could offer a possible molecular explanation of the resistance mechanism by mutation I261M

    Recombinant adeno associated viral (AAV) vector type 9 delivery of Ex1-Q138-mutant huntingtin in the rat striatum as a short-time model for in vivo studies in drug discovery

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    Huntington's disease (HD) is an inherited neurodegenerative disorder characterized by dyskinesia, cognitive impairment and emotional disturbances, presenting progressive neurodegeneration in the striatum and intracellular mutant Huntingtin (mHTT) aggregates in various areas of the brain. Recombinant Adeno Associated Viral (rAAV) vectors have been successfully used to transfer foreign genes to the brain of adult animals. In the present study we report a novel in vivo rat HD model obtained by stereotaxic injection of rAAV serotype2/9 containing Exon1-Q138 mHTT (Q138) and Exon1-Q17 wild type HTT (Q17; control), respectively in the right and in the left striatum, and expressed as C-terminal GFP fusions to facilitate detection of infected cells and aggregate production. Immunohistochemical analysis of brain slices from animals sacrificed twenty-one days after viral infection showed that Q138 injection resulted in robust formation of GFP-positive aggregates in the striatum, increased GFAP and microglial activation and neurodegeneration, with little evidence of any of these events in contralateral tissue infected with wild type (Q17) expressing construct. Differences in the relative metabolite concentrations (N-Acetyl Aspartate/Creatine and Myo-Inositol/Creatine) were observed by H1 MR Spectroscopy. By quantitative RT-PCR we also demonstrated that mHTT induced changes in the expression of genes previously shown to be altered in other rodent HD models. Importantly, administration of reference compounds previously shown to ameliorate the aggregation and neurodegeneration phenotypes in preclinical HD models was demonstrated to revert the mutant HTT-dependent effects in our model. In conclusion, the AAV2/9-Q138/Q17 exon 1 HTT stereotaxic injection represents a useful first-line in vivo preclinical model for studying the biology of mutant HTT exon 1 in the striatum and to provide early evidence of efficacy of therapeutic approaches

    Sensorised child walker for the assessment of rehabilitation therapies

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    The balance and corporal position of people with movement disorders improve when walkers or devices for the mobility aid are used [1]. The ability to walk and interact with the environment causes improvements in the gait, the muscle strength, the endurance, and the muscle innervation. In addition, the use of gait support systems promotes user participation and interaction, giving them greater autonomy and a better life quality. There are many works that offer solutions adapted to the patient's condition and their pathology and allow doctors to personalize rehabilitation therapies based on patient’s evolution [2, 3]. However, many static training platforms, pediatric exoskeletons and smart walkers can be unfeasible for most rehabilitation centers. This project addresses the development of an affordable sensorised walker capable of detecting and storing parameters induced by the patient in a passive posterior walker prototype. The walker is designed for training the gait and monitoring of the patient’s progress. In this way, professionals in the rehabilitation field such as orthopedists, doctors and physiotherapists will be able to use the electronic instrumentation of the walker to complement the obtained information through observational assessment scales and personalize recovery therapies taking into account the data provided by each user in the performed tests.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Randomised phase 3 open-label trial of first-line treatment with gemcitabine in association with docetaxel or paclitaxel in women with metastatic breast cancer: a comparison of different schedules and treatments

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    BACKGROUND: This open-label study compared docetaxel/gemcitabine vs. paclitaxel/gemcitabine and a weekly (W) vs. 3-weekly (3 W) schedule in metastatic breast cancer (MBC). METHODS: Patients relapsed after adjuvant/neoadjuvant anthracycline-containing chemotherapy were randomized to: A) gemcitabine 1000 mg/m(2) Day 1,8 + docetaxel 75 mg/m(2) Day 1 q3W; B) gemcitabine 1250 mg/m(2) Day 1,8 + paclitaxel 175 mg/m(2) Day 1 q3W; C) gemcitabine 800 mg/m(2) Day 1,8,15 + docetaxel 30 mg/m(2) Day 1,8,15 q4W; D) gemcitabine 800 mg/m(2) Day 1,15 + paclitaxel 80 mg/m(2) Day 1,8,15 q4W. Primary endpoint was time-to-progression (TTP). Secondary endpoints were overall survival (OS) and overall response rate (ORR). RESULTS: Interim analysis led to accrual interruption (241 patients enrolled of 360 planned). Median TTP (months) was 8.33 (95% CI: 6.19-10.16) with W and 7.51 (95% CI: 5.93-8.33) with 3 W (p=0.319). No differences were observed in median TTP between docetaxel and paclitaxel, with 85.6% and 87.0% of patients progressing, respectively. OS did not differ between regimens/schedules. ORR was comparable between regimens (HR: 0.882; 95% CI: 0.523-1.488; p=0.639), while it was significantly higher in W than in the 3 W (HR: 0.504; 95% CI: 0.299-0.850; p=0.010) schedule. Grade 3/4 toxicities occurred in 69.2% and 71.9% of patients on docetaxel and paclitaxel, and in 65.8% and 75.2% in W and 3 W. CONCLUSIONS: Both treatment regimens showed similar TTP. W might be associated with a better tumour response compared with 3 W. TRIAL REGISTRATION: Clinicaltrial.gov ID NCT0023689

    Comunicación y Chagas : Bases para un diálogo urgente

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    El 14 de abril de 2020 se conmemoró por primera vez en la historia, de manera oficial, el Día Mundial de la Enfermedad de Chagas. La fecha, inicialmente propuesta por la Federación Internacional de Asociaciones de Personas Afectadas por el Chagas (FINDECHAGAS), fue aprobada por la Asamblea Mundial de la Salud en mayo de 2019. En Argentina conmemoramos ese día realizando el conversatorio virtual “Comunicación y Chagas. ¿Para qué?” organizado por el Grupo ¿De qué hablamos cuando hablamos de Chagas? y el Programa Nacional de Chagas del Ministerio de Salud de la Nación. La idea surgió de una charla informal entre integrantes de ambos espacios, como una manera de responder al desafío que nos planteaba el poner en agenda una fecha tan especial en el contexto de la Pandemia COVID-19 y transitando las primeras semanas del Aislamiento Social Preventivo y Obligatorio (ASPO). El conversatorio surgió en respuesta a la necesidad de generar un espacio donde las reflexiones en torno a la comunicación sobre la problemática de Chagas sean consideradas al mismo nivel que aquellas vinculadas con el control vectorial, el diagnóstico y el tratamiento. Nos propusimos pensar y discutir colectivamente sobre la comunicación y las múltiples dimensiones que atraviesan al Chagas en los distintos escenarios donde está presente; entendiendo que -muchas veces- la comunicación es un componente subestimado, descontextualizado y alejado de las realidades concretas (y diversas) de las personas con Chagas y de la complejidad propia de esta problemática. Como parte de este proceso también decidimos elaborar un documento de reflexiones y recomendaciones sobre Comunicación y Chagas. Este documento que está hoy en nuestras manos es producto del compromiso de muchas personas que, el Día Mundial de Chagas 2020, nos sentimos interpeladas por la necesidad de hablar de Comunicación y Chagas.Asociación Civil Hablemos de Chaga

    Good survival outcome of metastatic SDH-deficient gastrointestinal stromal tumors harboring SDHA mutations

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    Purpose:A subset of patients with KIT/PDGFRA wild-type gastrointestinal stromal tumors show loss of function of succinate dehydrogenase, mostly due to germ-line mutations of succinate dehydrogenase subunits, with a predominance of succinate dehydrogenase subunit A. The clinical outcome of these patients seems favorable, as reported in small series in which patients were individually described. This work evaluates a retrospective survival analysis of a series of patients with metastatic KIT/PDGFRA wild-type succinate dehydrogenase-deficient gastrointestinal stromal tumors.Methods:Sixty-nine patients with metastatic gastrointestinal stromal tumors were included in the study (11 KIT/PDGFRA wild-type, of whom 6 were succinate dehydrogenase deficient, 5 were non-succinate dehydrogenase deficient, and 58 were KIT/PDGFRA mutant). All six succinate dehydrogenase-deficient patients harbored SDHA mutations. Kaplan-Meier curves and log-rank tests were used to compare the survival of patients with succinate dehydrogenase subunit A-mutant gastrointestinal stromal tumors with that of KIT/PDGFRA wild-type patients without succinate dehydrogenase deficiency and patients with KIT/PDGFRA-mutant gastrointestinal stromal tumors.Results:Follow-up ranged from 8.5 to 200.7 months. The difference between succinate dehydrogenase subunit A-mutant gastrointestinal stromal tumors and KIT/PDGFRA-mutant or KIT/PDGFRA wild-type non-succinate dehydrogenase deficient gastrointestinal stromal tumors was significant considering different analyses (P = 0.007 and P = 0.033, respectively, from diagnosis of gastrointestinal stromal tumor for the whole study population; P = 0.005 and P = 0.018, respectively, from diagnosis of metastatic disease for the whole study population; P = 0.007 for only patients who were metastatic at diagnosis).Conclusion:Patients with metastatic KIT/PDGFRA wild-type succinate dehydrogenase-deficient gastrointestinal stromal tumors harboring succinate dehydrogenase subunit A mutations present an impressively long survival. These patients should be identified in clinical practice to better tailor treatments and follow-up over time A subset of patients with KIT/PDGFRA wild-type gastrointestinal stromal tumors show loss of function of succinate dehydrogenase, mostly due to germ-line mutations of succinate dehydrogenase subunits, with a predominance of succinate dehydrogenase subunit A. The clinical outcome of these patients seems favorable, as reported in small series in which patients were individually described. This work evaluates a retrospective survival analysis of a series of patients with metastatic KIT/PDGFRA wild-type succinate dehydrogenase-deficient gastrointestinal stromal tumors.Methods:Sixty-nine patients with metastatic gastrointestinal stromal tumors were included in the study (11 KIT/PDGFRA wild-type, of whom 6 were succinate dehydrogenase deficient, 5 were non-succinate dehydrogenase deficient, and 58 were KIT/PDGFRA mutant). All six succinate dehydrogenase-deficient patients harbored SDHA mutations. Kaplan-Meier curves and log-rank tests were used to compare the survival of patients with succinate dehydrogenase subunit A-mutant gastrointestinal stromal tumors with that of KIT/PDGFRA wild-type patients without succinate dehydrogenase deficiency and patients with KIT/PDGFRA-mutant gastrointestinal stromal tumors.Results:Follow-up ranged from 8.5 to 200.7 months. The difference between succinate dehydrogenase subunit A-mutant gastrointestinal stromal tumors and KIT/PDGFRA-mutant or KIT/PDGFRA wild-type non-succinate dehydrogenase deficient gastrointestinal stromal tumors was significant considering different analyses (P = 0.007 and P = 0.033, respectively, from diagnosis of gastrointestinal stromal tumor for the whole study population; P = 0.005 and P = 0.018, respectively, from diagnosis of metastatic disease for the whole study population; P = 0.007 for only patients who were metastatic at diagnosis).Conclusion:Patients with metastatic KIT/PDGFRA wild-type succinate dehydrogenase-deficient gastrointestinal stromal tumors harboring succinate dehydrogenase subunit A mutations present an impressively long survival. These patients should be identified in clinical practice to better tailor treatments and follow-up over time

    Rolling Motion Along an Incline: Visual Sensitivity to the Relation Between Acceleration and Slope

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    People easily intercept a ball rolling down an incline, despite its acceleration varies with the slope in a complex manner. Apparently, however, they are poor at detecting anomalies when asked to judge artificial animations of descending motion. Since the perceptual deficiencies have been reported in studies involving a limited visual context, here we tested the hypothesis that judgments of naturalness of rolling motion are consistent with physics when the visual scene incorporates sufficient cues about environmental reference and metric scale, roughly comparable to those present when intercepting a ball. Participants viewed a sphere rolling down an incline located in the median sagittal plane, presented in 3D wide-field virtual reality. In different experiments, either the slope of the plane or the sphere acceleration were changed in arbitrary combinations, resulting in a kinematics that was either consistent or inconsistent with physics. In Experiment 1 (slope adjustment), participants were asked to modify the slope angle until the resulting motion looked natural for a given ball acceleration. In Experiment 2 (acceleration adjustment), instead, they were asked to modify the acceleration until the motion on a given slope looked natural. No feedback about performance was provided. For both experiments, we found that participants were rather accurate at finding the match between slope angle and ball acceleration congruent with physics, but there was a systematic effect of the initial conditions: accuracy was higher when the participants started the exploration from the combination of slope and acceleration corresponding to the congruent conditions than when they started far away from the congruent conditions. In Experiment 3, participants modified the slope angle based on an adaptive staircase, but the target never coincided with the starting condition. Here we found a generally accurate performance, irrespective of the target slope. We suggest that, provided the visual scene includes sufficient cues about environmental reference and metric scale, joint processing of slope and acceleration may facilitate the detection of natural motion. Perception of rolling motion may rely on the kind of approximate, probabilistic simulations of Newtonian mechanics that have previously been called into play to explain complex inferences in rich visual scenes
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