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31.
Claudia Compagnucci Sara Di Siena Maria Blaire Bustamante Daniele Di Giacomo Monia Di Tommaso Mauro Maccarrone Paola Grimaldi Claudio Sette 《PloS one》2013,8(1)
Neural stem cells (NSCs) are self-renewing cells that can differentiate into multiple neural lineages and repopulate regions of the brain after injury. We have investigated the role of endocannabinoids (eCBs), endogenous cues that modulate neuronal functions including neurogenesis, and their receptors CB1 and CB2 in mouse NSCs. Real-time PCR and Western blot analyses indicated that CB1 is present at higher levels than CB2 in NSCs. The eCB anandamide (AEA) or the CB1-specific agonist ACEA enhanced NSC differentiation into neurons, but not astrocytes and oligodendrocytes, whereas the CB2-specific agonist JWH133 was ineffective. Conversely, the effect of AEA was inhibited by CB1, but not CB2, antagonist, corroborating the specificity of the response. CB1 activation also enhanced maturation of neurons, as indicated by morphometric analysis of neurites. CB1 stimulation caused long-term inhibition of the ERK1/2 pathway. Consistently, pharmacological inhibition of the ERK1/2 pathway recapitulated the effects exerted by CB1 activation on neuronal differentiation and maturation. Lastly, gene array profiling showed that CB1 activation augmented the expression of genes involved in neuronal differentiation while decreasing that of stemness genes. These results highlight the role of CB1 in the regulation of NSC fate and suggest that its activation may represent a pro-neuronal differentiation signal. 相似文献
32.
Emiliano Ricciardi Giacomo Handjaras Daniela Bonino Tomaso Vecchi Luciano Fadiga Pietro Pietrini 《PloS one》2013,8(3)
The representation of actions within the action-observation network is thought to rely on a distributed functional organization. Furthermore, recent findings indicate that the action-observation network encodes not merely the observed motor act, but rather a representation that is independent from a specific sensory modality or sensory experience. In the present study, we wished to determine to what extent this distributed and ‘more abstract’ representation of action is truly supramodal, i.e. shares a common coding across sensory modalities. To this aim, a pattern recognition approach was employed to analyze neural responses in sighted and congenitally blind subjects during visual and/or auditory presentation of hand-made actions. Multivoxel pattern analyses-based classifiers discriminated action from non-action stimuli across sensory conditions (visual and auditory) and experimental groups (blind and sighted). Moreover, these classifiers labeled as ‘action’ the pattern of neural responses evoked during actual motor execution. Interestingly, discriminative information for the action/non action classification was located in a bilateral, but left-prevalent, network that strongly overlaps with brain regions known to form the action-observation network and the human mirror system. The ability to identify action features with a multivoxel pattern analyses-based classifier in both sighted and blind individuals and independently from the sensory modality conveying the stimuli clearly supports the hypothesis of a supramodal, distributed functional representation of actions, mainly within the action-observation network. 相似文献
33.
Giovanni Benelli Elisa Donati Donato Romano Giacomo Ragni Gabriella Bonsignori Cesare Stefanini Angelo Canale 《Insect Science》2016,23(6):869-880
Variations in male body size are known to affect inter‐ and intrasexual selection outcomes in a wide range of animals. In mating systems involving sexual signaling before mating, body size often acts as a key factor affecting signal strength and mate choice. We evaluated the effect of male size on courtship displays and mating success of the olive fruit fly, Bactrocera oleae (Diptera: Tephritidae). Wing vibrations performed during successful and unsuccessful courtships by large and small males were recorded by high‐speed videos and analyzed through frame‐by‐frame analysis. Mating success of large and small males was investigated. The effect of male–male competition on mating success was evaluated. Male body size affected both male courtship signals and mating outcomes. Successful males showed wing‐borne signals with high frequencies and short interpulse intervals. Wing vibrations displayed by successful large males during copulation attempt had higher frequencies over smaller males and unsuccessful large males. In no‐competition conditions, large males achieved higher mating success with respect to smaller ones. Allowing large and small males to compete for a female, large males achieve more mating success over smaller ones. Mate choice by females may be based on selection of the larger males, able to produce high‐frequency wing vibrations. Such traits may be indicative of “good genes,” which under sexual selection could means good social‐interaction genes, or a good competitive manipulator of conspecifics. 相似文献
34.
Giacomo De Luca Silvia Laura Bosello Francesca Augusta Gabrielli Giorgia Berardi Federico Parisi Manuela Rucco Giovanni Canestrari Francesco Loperfido Leonarda Galiuto Filippo Crea Gianfranco Ferraccioli 《PloS one》2016,11(4)
BackgroundArrhythmias are frequent in Systemic Sclerosis (SSc) and portend a bad prognosis, accounting alone for 6% of total deaths. Many of these patients die suddenly, thus prevention and intensified risk-stratification represent unmet medical needs. The major goal of this study was the definition of ECG indexes of poor prognosis.MethodsWe performed a prospective cohort study to define the role of 24h-ECG-Holter as an additional risk-stratification technique in the identification of SSc-patients at high risk of life-threatening arrhythmias and sudden cardiac death (SCD). One-hundred SSc-patients with symptoms and/or signs suggestive of cardiac involvement underwent 24h-ECG-Holter. The primary end-point was a composite of SCD or need for implantable cardioverter defibrillator (ICD).ResultsFifty-six patients (56%) had 24h-ECG-Holter abnormalities and 24(24%) presented frequent ventricular ectopic beats (VEBs). The number of VEBs correlated with high-sensitive cardiac troponin T (hs-cTnT) levels and inversely correlated with left-ventricular ejection fraction (LV-EF) on echocardiography. During a mean follow-up of 23.1±16.0 months, 5 patients died suddenly and two required ICD-implantation. The 7 patients who met the composite end-point had a higher number of VEBs, higher levels of hs-cTnT and NT-proBNP and lower LV-EF (p = 0.001 for all correlations). All these 7 patients had frequent VEBs, while LV-EF was not reduced in all and its range was wide. At ROC curve, VEBs>1190/24h showed 100% of sensitivity and 83% of specificity to predict the primary end-point (AUROC = 0.92,p<0.0001). Patients with VEBS>1190/24h had lower LV-EF and higher hs-cTnT levels and, at multivariate analysis, the presence of increased hs-cTnT and of right bundle branch block on ECG emerged as independent predictors of VEBs>1190/24h. None of demographic or disease-related characteristics emerged as predictors of poor outcome.ConclusionsVEBS>1190/24h identify patients at high risk of life-threatening arrhythmic complications. Thus, 24h-ECG-Holter should be considered a useful additional risk-stratification test to select SSc-patients at high-risk of SCD, in whom an ICD-implantation could represent a potential life-saving intervention. 相似文献
35.
Regina Maria Barbosa Cristiane da Silva Cabral Tania di Giacomo do Lago Adriana de Araujo Pinho 《PloS one》2016,11(11)
BackgroundIn many countries, young women of reproductive age have been especially affected by the HIV epidemic, which have fostered research to better understand how HIV infection influences and shapes women´s fertility and reproductive and sexual decisions. In Brazil, few studies have focused on the impact of the HIV epidemic on contraceptive choices among women living with HIV (WLHIV).ObjectiveThis study evaluates the impact HIV infection may have in the access to female sterilization in Brazil, using a time-to-event analysis.MethodsA cross-sectional quantitative study (GENIH study) was conducted between February 2013 and April 2014 in the city of São Paulo, comparing two probabilistic samples of 975 WLHIV and 1,003 women not living with HIV (WNLHIV) aged 18 to 49. Sexual and reproductive data was collected retrospectively in order to reconstruct women''s reproductive trajectories. Given the objectives of this study, the analysis was restricted to women with parity one or more and, in case of WLHIV, to those sterilized after HIV diagnosis and not infected through vertical transmission. The final sample analysis included 683 WNLHIV and 690 WLHIV. A series of multivariable-adjusted Cox models estimated the probability of being sterilized after HIV diagnosis, compared with WNLHIV. Models were adjusted for schooling, race/color, and stratified by parity at last delivery (1–2, 3+). Hazard ratios were calculated for female sterilization, and separately for interval and postpartum procedures (performed in conjunction with caesarean section or immediately after vaginal delivery). Additionally, information regarding unmet demand for female sterilization was also explored.FindingsNo statistical difference in the overall risk of sterilization between WLHIV and WNLHIV in the two parity-related groups is observed: HR = 0.88 (0.54–1.43) and 0.94 (0.69–1.29), respectively, among women with 1–2 children and those with three and more. However, significant differences regarding the impact of HIV infection at sterilization are observed depending on the timing and the type of sterilization procedure. The probability of obtaining an interval sterilization is significantly lower for WLHIV compared to those not living with HIV. The reverse occurs regarding postpartum sterilization. Although sterilization is mainly performed in conjunction with caesarean section in Brazil, it is evident that caesarean sections are not the sole factor increasing the risk of sterilization among WLHIV.ConclusionThe results indicate barriers in the access to services offering interval sterilization for WLHIV and certain facilitation in obtaining the procedure in conjunction with caesarean section. Health policy makers at local and national levels should promote institutional changes in order to facilitate access to interval sterilization and to confront the sensitive discussion of WLHIV’s eligibility for postpartum sterilization. It is also urgent to increase access to a wider range of contraceptive methods for WLHIV and promote dual method protection strategies. Moreover, since condom use may decrease in the future in the context of the preventive effect of antiretroviral therapy, promoting dual methods will expand the choices regarding the reproductive rights of women living with HIV. 相似文献
36.
37.
Riccardo Marzuoli Robert Monga Angelo Finco Giacomo Gerosa 《Trees - Structure and Function》2016,30(6):1995-2010
Key message
The root biomass of oak young trees significantly decreased after 2 years of exposure to high levels of ozone, but increased nitrogen wet deposition tended to partly contrast this effect.Abstract
A 2-year Open-Top Chamber (OTC) experiment with young Quercus robur trees that were exposed to different levels of ozone (O3) and nitrogen deposition was performed in Curno (Northern Italy) for the FP7 Project ÉCLAIRE. The plants were exposed to four levels of ozone (?40 % of ambient ozone in charcoal-filtered OTCs, ?5 % in non-filtered OTCs, and +30 and +75 % in O3-enriched OTCs) and two levels of nitrogen wet deposition (tap water and tap water +70 kg N ha?1 year?1). The stomatal conductance and A/Ci response curves were measured during the two experimental seasons, and in October, the plant dry biomass partition between the roots and stem was assessed. Oak plants were moderately sensitive to O3. After the second year of treatments, the dose–response relationships based on the O3 stomatal flux indicated a 4.6 % of root biomass loss and a 12.1 % of reduction of the number of leaves per 10 mmol O3 m?2 absorbed by plants grown with no nitrogen addition. Ozone also decreased both the stomatal conductance and the maximum carboxylation rate allowed by Rubisco (V cmax) during the first year of treatments. However, the effect on V cmax was lost during the second year, and the plants showed an uncoupling between leaf-level physiological responses and plant-level biomass responses. Increased nitrogen deposition enhanced the growth of plants and partially mitigated the O3 impact on biomass and physiology, but no significant effect of the interaction between the two factors was found. The data that were collected could contribute to the definition of the O3 dose–response relationships based on biomass losses for deciduous trees in Southern Europe climatic conditions and could improve the O3 risk assessment models by providing new information about the effect of increased nitrogen deposition on the ozone impact.38.
Delia Gagliardi Giacomo P. Comi Nereo Bresolin Stefania Corti 《Journal of cellular and molecular medicine》2019,23(3):1647-1656
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder affecting upper and lower motor neurons (MNs), resulting in paralysis and precocious death from respiratory failure. Although the causes of ALS are incompletely understood, the role of alterations in RNA metabolism seems central. MicroRNAs (miRNAs) are noncoding RNAs implicated in the regulation of gene expression of many relevant physiological processes, including cell death. The recent model of programmed cell death (PCD) encompasses different mechanisms, from apoptosis to regulated necrosis (RN), in particular necroptosis. Both apoptosis and necroptosis play a significant role in the progressive death of MNs in ALS. In this review, we present key research related to miRNAs that modulate apoptosis and RN pathways in ALS. We also discuss whether these miRNAs represent potential targets for therapeutic development in patients. 相似文献
39.
Soru Santina Malavasi Veronica Caboni Pierluigi Concas Alessandro Cao Giacomo 《Extremophiles : life under extreme conditions》2019,23(1):79-89
Extremophiles - The extremophile green alga Coccomyxa melkonianii SCCA 048 was investigated to evaluate its ability to grow in culture media with different pH. Specifically, Coccomyxa melkonianii... 相似文献
40.
Gustavo Benevides Martins Giacomo Giacomelli Oliver Goldbeck Gerd M. Seibold Marc Bramkamp 《Molecular microbiology》2019,111(5):1335-1354
Many bacteria take up carbohydrates by membrane‐integral sugar specific phosphoenolpyruvate‐dependent carbohydrate:phosphotransferase systems (PTS). Although the PTS is centrally involved in regulation of carbon metabolism in different bacteria, little is known about localization and putative oligomerization of the permease subunits (EII). Here, we analyzed localization of the fructose specific PtsF and the glucose specific PtsG transporters, as well as the general components EI and HPr from Corynebacterium glutamicum using widefield and single molecule localization microscopy. PtsF and PtsG form membrane embedded clusters that localize in a punctate pattern. Size, number and fluorescence of the membrane clusters change upon presence or absence of the transported substrate, and a direct influence of EI and HPr was not observed. In presence of the transport substrate, EII clusters significantly increased in size. Photo‐activated localization microscopy data revealed that, in presence of different carbon sources, the number of EII proteins per cluster remains the same, however, the density of these clusters reduces. Our work reveals a simple mechanism for efficient membrane occupancy regulation. Clusters of PTS EII transporters are densely packed in absence of a suitable substrate. In presence of a transported substrate, the EII proteins in individual clusters occupy larger membrane areas. 相似文献