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31.
Ada Rispoli Elena Cipollini Sandra Catania Rossella Di Giaimo Giuseppe Pulice Stineke van Houte Francesca Sparla Fabrizio Dal Piaz Davide Roncarati Paolo Trost Marialuisa Melli 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(12):2591-2599
Cystatin B (CSTB) is an anti-protease frequently mutated in progressive myoclonus epilepsy (EPM1), a devastating degenerative disease. This work shows that rat CSTB is an unstable protein that undergoes structural changes following the interaction with a chaperone, either prokaryotic or eukaryotic. Both the prokaryotic DnaK and eukaryotic HSP70 promote CSTB polymerization. Denaturated CSTB is polymerized by the chaperone alone. Native CSTB monomers are more stable than denatured monomers and require Cu2 + for chaperone-dependent polymerization. Cu2 + interacts with at least two conserved histidines, at positions 72 and 95 modifying the structure of native monomeric CSTB. Subsequently, CSTB becomes unstable and readily responds to the addition of DnaK or HSP70, generating polymers. This reaction depends strictly on the presence of this divalent metal ion and on the presence of one cysteine in the protein chain. The cysteine deletion mutant does not polymerize. We propose that Cu2 + modifies the redox environment of the protein, allowing the oxidation of the cysteine residue of CSTB that triggers polymerization. These polymers are sensitive to reducing agents while polymers obtained from denatured CSTB monomers are DTT resistant. We propose that the Cu2 +/HSP70 dependent polymers are physiological and functional in eukaryotic cells. Furthermore, while monomeric CSTB has anti-protease function, it seems likely that polymeric CSTB fulfils different function(s). 相似文献
32.
Friederike A. Schulte Davide Ruffoni Floor M. Lambers David Christen Duncan J. Webster Gisela Kuhn Ralph Müller 《PloS one》2013,8(4)
Bone is able to react to changing mechanical demands by adapting its internal microstructure through bone forming and resorbing cells. This process is called bone modeling and remodeling. It is evident that changes in mechanical demands at the organ level must be interpreted at the tissue level where bone (re)modeling takes place. Although assumed for a long time, the relationship between the locations of bone formation and resorption and the local mechanical environment is still under debate. The lack of suitable imaging modalities for measuring bone formation and resorption in vivo has made it difficult to assess the mechanoregulation of bone three-dimensionally by experiment. Using in vivo micro-computed tomography and high resolution finite element analysis in living mice, we show that bone formation most likely occurs at sites of high local mechanical strain (p<0.0001) and resorption at sites of low local mechanical strain (p<0.0001). Furthermore, the probability of bone resorption decreases exponentially with increasing mechanical stimulus (R2 = 0.99) whereas the probability of bone formation follows an exponential growth function to a maximum value (R2 = 0.99). Moreover, resorption is more strictly controlled than formation in loaded animals, and ovariectomy increases the amount of non-targeted resorption. Our experimental assessment of mechanoregulation at the tissue level does not show any evidence of a lazy zone and suggests that around 80% of all (re)modeling can be linked to the mechanical micro-environment. These findings disclose how mechanical stimuli at the tissue level contribute to the regulation of bone adaptation at the organ level. 相似文献
33.
Decision-Making in Multiple Sclerosis Consultations in Italy: Third Observer and Patient Assessments
Erika Pietrolongo Andrea Giordano Monica Kleinefeld Paolo Confalonieri Alessandra Lugaresi Carla Tortorella Maura Pugliatti Davide Radice Claudia Goss Christoph Heesen Alessandra Solari the AutoMS group 《PloS one》2013,8(4)
Objective
To assess decision-making in multiple sclerosis (MS) from third observer and patient perspectives.Method
Audio recordings of first-ever consultations with a participating physician (88 outpatients, 10 physicians) at four tertiary MS care clinics in Italy, were rated by a third observer using the Observing Patient Involvement in Shared Decision Making (OPTION) and by patients using the Perceived Involvement in Care Scale (PICS).Results
Mean patient age was 37.5, 66% were women, 72% had MS, and 28% had possible MS or other disease. Mean PICS subscale scores (range 0 poor, 100 best possible) were 71.9 (SD 24.3) for "physician facilitation" (PICS-F); 74.6 (SD 22.9) for "patient information exchange" (PICS-I); and only 22.5 (SD 16.2) for "patient decision making" (PICS-DM). Mean OPTION total score (0 poor, 100 best possible) was 29.6 (SD 10.3). Poorest OPTION scores were found for items assessing “preferred patient approach to receiving information” and “preferred patient level of involvement.” Highest scores were for “clinician drawing attention to identified problem”, “indicating need for decision making,” and “need to review the decision.” Consultation time, woman physician, patient-physician gender concordance and PICS-F were associated with higher OPTION total score; older physician and second opinion consultation were associated with lower OPTION score.Conclusions
In line with findings in other settings, our third observer findings indicated limited patient involvement abilities of MS physicians during first consultations. Patient perceptions of physician skills were better than third observers’, although they correlated. Consultations with women physicians, and younger physicians, were associated with higher third observer and patient-based scores. Our findings reveal a need to empower Italian MS physicians with better communication and shared decision-making skills, and show in particular that attention to MS patient preferences for reception of information and involvement in health decisions, need to be improved. 相似文献34.
Emanuela Foglia Paolo Bonfanti Giuliano Rizzardini Erminio Bonizzoni Umberto Restelli Elena Ricci Emanuele Porazzi Francesca Scolari Davide Croce 《PloS one》2013,8(2)
Objective
To estimate the lifetime cost utility of two antiretroviral regimens (once-daily atazanavir plus ritonavir [ATV+r] versus twice-daily lopinavir/ritonavir [LPV/r]) in Italian human immunodeficiency virus (HIV)-infected patients naïve to treatment.Design
With this observational retrospective study we collected the clinical data of a cohort of HIV-infected patients receiving first-line treatment with LPV/r or ATV+r.Methodology
A Markov microsimulation model including direct costs and health outcomes of first- and second-line highly active retroviral therapy was developed from a third-party (Italian National Healthcare Service) payer’s perspective. Health and monetary outcomes associated with the long-term use of ATV+r and LPV/r regimens were evaluated on the basis of eight health states, incidence of diarrhoea and hyperbilirubinemia, AIDS events, opportunistic infections, coronary heart disease events and, for the first time in an economic evaluation, chronic kidney disease (CKD) events. In order to account for possible deviations between real-life data and randomised controlled trial results, a second control arm (ATV+r 2) was created with differential transition probabilities taken from the literature.Results
The average survival was 24.061 years for patients receiving LPV/r, 24.081 and 24.084 for those receiving ATV+r 1 and 2 respectively. The mean quality-adjusted life-years (QALYs) were higher for the patients receiving LPV/r than those receiving ATV+r (13.322 vs. 13.060 and 13.261 for ATV+r 1 and 2). The cost-utility values were 15,310.56 for LPV/r, 15,902.99 and 15,524.85 for ATV+r 1 and 2.Conclusions
Using real-life data, the model produced significantly different results compared with other studies. With the innovative addition of an evaluation of CKD events, the model showed a cost-utility value advantage for twice-daily LPV/r over once-daily ATV+r, thus providing evidence for its continued use in the treatment of HIV. 相似文献35.
Sunita S. Balla-Jhagjhoorsingh Davide Corti Leo Heyndrickx Elisabeth Willems Katleen Vereecken David Davis Guido Vanham 《PloS one》2013,8(7)
Immunogen design for HIV-1 vaccines could be based on epitope identification of naturally occurring neutralizing antibodies in infected patients. A tier 2 neutralizing monoclonal antibody (mAb), HJ16 recognizes a new epitope in the CD4 binding site (CD4bs) region that only partially overlaps with the b12 epitope. We aimed to identify the critical binding site by resistance induction in a sensitive primary CRF02_AG strain. In four independent dose-escalation studies, the N276D mutation was consistently the only alteration found and it was confirmed to be responsible for resistance to HJ16 by site-directed mutagenesis in envelopes (envs) of the homologous CRF02_AG, as well as of a subtype A and a subtype C primary isolate. This mutation removes an N-linked glycosylation site. The effect of N276D was very selective, as it failed to confer resistance to a range of other entry inhibitors. Remarkably, sensitivity to the CD4bs VRC01 and VRC03 mAbs was increased in the N276D mutated viruses. These data indicate that binding of the CD4bs specific HJ16 mAb critically depends on the interaction with the N276-glycan, thus indicating that HJ16 is the first glycan dependent CD4bs-specific mAb. 相似文献
36.
Hans P. Püschel Joseph E. O'Reilly Davide Pisani Philip C. J. Donoghue 《Palaeontology》2020,63(1):67-83
The molecular clock provides the only viable means of establishing realistic evolutionary timescales but it remains unclear how best to calibrate divergence time analyses. Calibrations can be applied to the tips and/or to the nodes of a phylogeny. Tip-calibration is an attractive approach since it allows fossil species to be included alongside extant relatives in molecular clock analyses. However, most fossil species are known from multiple stratigraphical horizons and it remains unclear how such age ranges should be interpreted to codify tip-calibrations. We use simulations and empirical data to explore the impact on precision and accuracy of different approaches to informing tip-calibrations. In particular, we focus on the effect of using tip-calibrations defined using the oldest vs youngest stratigraphic occurrences, the full stratigraphical range, as well as confidence intervals on these data points. The results of our simulations show that using different calibration approaches leads to different divergence-time estimates and demonstrate that concentrating tip-calibrations near the root of the dated phylogeny improves both precision and accuracy of estimated divergence times. Finally, our results indicate that the highest levels of accuracy and precision are achieved when fossil tips are calibrated based on the fossil occurrence from which the morphological data were derived. These trends were corroborated by analysis of an empirical dataset for Ursidae. Overall, we conclude that tip-dating analyses should, in particular, employ tip calibrations close to the root of the tree and they should be calibrated based on the age of the fossil used to inform the morphological data used in Total Evidence Dating. 相似文献
37.
Seveso Davide Arrigoni Roberto Montano Simone Maggioni Davide Orlandi Ivan Berumen Michael L. Galli Paolo Vai Marina 《Coral reefs (Online)》2020,39(1):85-98
Coral Reefs - Coral bleaching represents the most serious threat to contemporary coral reefs. In response, focus is being laid on understanding the cellular processes involved in the response of... 相似文献
38.
Vanessa Castelli Francesco Melani Claudio Ferri Michele d'Angelo Mariano Catanesi Davide Grassi Elisabetta Benedetti Antonio Giordano Annamaria Cimini Giovambattista Desideri 《Journal of cellular biochemistry》2020,121(12):4862-4869
Oxidative stress is considered the common effector of the cascade of degenerative events in many neurological conditions. Thus, in this paper we tested different nutraceuticals in H2O2 in vitro model to understand if could represent an adjuvant treatment for neurological diseases. In this study, nutraceuticals bacopa, lycopene, astaxanthin, and vitamin B12 were used alone or in combination in human neuronal differentiated SH-SY5Y cells upon hydrogen peroxide-induced injury and neuroprotective, neuronal death pathways were analyzed. The nutraceuticals analyzed were able to protect H2O2 cytotoxic effects, through increasing cell viability and proteins involved in neuroprotection pathways and restoring proteins involved in cell death pathways. On this basis, it is possible to propose the use of these compounds as dietary supplement for the prevention or as adjuvant to the only symptomatic treatments so far available for neurodegenerative diseases. 相似文献
39.
40.
Annamaria Spina Luca Sorvillo Francesca Di Maiolo Antonietta Esposito Raffaella D'Auria Davide Di Gesto Emilio Chiosi Silvio Naviglio 《Journal of cellular physiology》2013,228(1):198-206
Osteosarcoma is the most common malignant primary bone tumor in children and adolescents. The clinical outcome for osteosarcoma remains discouraging despite aggressive surgery and intensive radiotherapy and chemotherapy regimens. Thus, novel therapeutic approaches are needed. Previously, we have shown that inorganic phosphate (Pi) inhibits proliferation and aggressiveness of human osteosarcoma U2OS cells identifying adenylate cyclase, beta3 integrin, Rap1, ERK1/2 as proteins whose expression and function are relevantly affected in response to Pi. In this study, we investigated whether Pi could affect chemosensitivity of osteosarcoma cells and the underlying molecular mechanisms. Here, we report that Pi inhibits proliferation of p53‐wild type U2OS cells (and not of p53‐null Saos and p53‐mutant MG63 cells) by slowing‐down cell cycle progression, without apoptosis occurrence. Interestingly, we found that Pi strongly enhances doxorubicin‐induced cytotoxicity in U2OS, and not in Saos and MG63 cells, by apoptosis induction, as revealed by a marked increase of sub‐G1 population, Bcl‐2 downregulation, caspase‐3 activation, and PARP cleavage. Remarkably, Pi/doxorubicin combination‐induced cytotoxicity was accompanied by an increase of p53 protein levels and of p53 target genes mdm2, p21 and Bax, and was significantly reduced by the p53 inhibitor pifithrine‐alpha. Moreover, the doxorubicin‐induced cytotoxicity was associated with ERK1/2 pathway inhibition in response to Pi. Altogether, our data enforce the evidence of Pi as a novel signaling molecule capable of inhibiting ERK pathway and inducing sensitization to doxorubicin of osteosarcoma cells by p53‐dependent apoptosis, implying that targeting Pi levels might represent a rational strategy for improving osteosarcoma therapy. J. Cell. Physiol. 228: 198–206, 2013. © 2012 Wiley Periodicals, Inc. 相似文献