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931.
RAC3 influences the chemoresistance of colon cancer cells through autophagy and apoptosis inhibition
María Fernanda Rubio María Cecilia Lira Francisco Damián Rosa Adrían Dario Sambresqui María Cecilia Salazar Güemes Mónica Alejandra Costas 《Cancer cell international》2017,17(1):111
Background
RAC3 coactivator overexpression has been implicated in tumorigenesis, contributing to inhibition of apoptosis and autophagy. Both mechanisms are involved in resistance to treatment with chemotherapeutic agents. The aim of this study was to investigate its role in chemoresistance of colorectal cancer.Methods
The sensitivity to 5-fluorouracil and oxaliplatin in colon cancer cells HT-29, HCT 116 and Lovo cell lines, expressing high or low natural levels of RAC3, was investigated using viability assays.Results
In HCT 116 cells, we found that although 5-fluorouracil was a poor inducer of apoptosis, autophagy was strongly induced, while oxaliplatin has shown a similar ability to induce both of them. However, in HCT 116 cells expressing a short hairpin RNA for RAC3, we found an increased sensitivity to both drugs if it is compared with control cells. 5-Fluorouracil and oxaliplatin treatment lead to an enhanced caspase 3-dependent apoptosis and produce an increase of autophagy. In addition, both process have shown to be trigged faster than in control cells, starting earlier after stimulation.Conclusions
Our results suggest that RAC3 expression levels influence the sensitivity to chemotherapeutic drugs. Therefore, the knowledge of RAC3 expression levels in tumoral samples could be an important contribution to design new improved therapeutic strategies in the future.932.
Carmine Mancone Alessio Grimaldi Giulia Refolo Isabella Abbate Gabriella Rozera Dario Benelli Gian Maria Fimia Vincenzo Barnaba Marco Tripodi Mauro Piacentini Fabiola Ciccosanti 《Proteome science》2017,15(1):18
Background
Changes in iron metabolism frequently accompany HIV-1 infection. However, while many clinical and in vitro studies report iron overload exacerbates the development of infection, many others have found no correlation. Therefore, the multi-faceted role of iron in HIV-1 infection remains enigmatic.Methods
RT-qPCR targeting the LTR region, gag, Tat and Rev were performed to measure the levels of viral RNAs in response to iron overload. Spike-in SILAC proteomics comparing i) iron-treated, ii) HIV-1-infected and iii) HIV-1-infected/iron treated T lymphocytes was performed to define modifications in the host cell proteome. Data from quantitative proteomics were integrated with the HIV-1 Human Interaction Database for assessing any viral cofactors modulated by iron overload in infected T lymphocytes.Results
Here, we demonstrate that the iron overload down-regulates HIV-1 gene expression by decreasing the levels of viral RNAs. In addition, we found that iron overload modulates the expression of many viral cofactors. Among them, the downregulation of the REV cofactor eIF5A may correlate with the iron-induced inhibition of HIV-1 gene expression. Therefore, we demonstrated that eiF5A downregulation by shRNA resulted in a significant decrease of Nef levels, thus hampering HIV-1 replication.Conclusions
Our study indicates that HIV-1 cofactors influenced by iron metabolism represent potential targets for antiretroviral therapy and suggests eIF5A as a selective target for drug development.933.
Maria Rosaria Iovene Francesca Bombace Roberta Maresca Anna Sapone Patrizia Iardino Annarita Picardi Rosa Marotta Chiara Schiraldi Dario Siniscalco Nicola Serra Laura de Magistris Carmela Bravaccio 《Mycopathologia》2017,182(3-4):349-363
High frequency of gastrointestinal yeast presence in ASD subjects was shown through a simple cultural approach (Candida spp. in 57.5 % of ASDs and no controls); the identification of aggressive form (pseudo-hyphae presenting) of Candida spp. at light microscope means that adhesion to intestinal mucosa is facilitated. Dysbiosis appears sustained by lowered Lactobacillus spp. and decreased number of Clostridium spp. Absence of C. difficilis and its toxins in both ASDs and controls is also shown. Low-mild gut inflammation and augmented intestinal permeability were demonstrated together with the presence of GI symptoms. Significant linear correlation was found between disease severity (CARs score) and calprotectin and Clostridium spp. presence. Also GI symptoms, such as constipation and alternating bowel, did correlate (multivariate analyses) with the increased permeability to lactulose. The present data provide rationale basis to a possible specific therapeutic intervention in restoring gut homeostasis in ASDs. 相似文献
934.
Dario Ottonello Stefania D’Angelo Fabrizio Oneto Stefano Malavasi Marco Alberto Luca Zuffi 《Ecological Research》2017,32(1):71-80
Feeding ecology of a species is the result of its evolutionary history, biology, physiology and local constraints, such as prey availability, intra- and inter-specific interactions and environmental characteristics. In this study we investigated the still unknown diet of the Sicilian pond turtle, with special emphasis to the relationships with recently introduced alien species in the “Lake Preola and Gorghi Tondi” Nature Reserve (Sicily, Italy). A total of 83 faecal samples were collected in three different periods. Emys trinacris seems an opportunistic and generalist species. The main prey taxa were aquatic invertebrates, including the invasive Procambarus clarkii, while non-aquatic preys are found sporadically. Plant matter, mainly leaves and roots of aquatic forms, was also found in high frequency with a high occurrence of fruits and seeds in spring. We did not find a significant difference in diet composition within sex and age, while an evident divergence was found between periods and sites. In particular, we noticed a decrease in prey abundance and in food-niche breadth from pre-reproductive period to post-reproductive period. Moreover a very clear difference was found between a site with allochthonous fishes and a site fish-free, with a more abundant and wide diet spectrum in the last one, as a result of the increased availability of prey. We highlighted the importance to take any possible actions to avoid the spread of fishes in other basins and to study the indirect impact of Procambarus clarkii, as possible vector of harmful trace element. 相似文献
935.
Effects of three global change drivers on terrestrial C:N:P stoichiometry: a global synthesis 总被引:1,自引:0,他引:1
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Kai Yue Dario A. Fornara Wanqin Yang Yan Peng Zhijie Li Fuzhong Wu Changhui Peng 《Global Change Biology》2017,23(6):2450-2463
Over the last few decades, there has been an increasing number of controlled‐manipulative experiments to investigate how plants and soils might respond to global change. These experiments typically examined the effects of each of three global change drivers [i.e., nitrogen (N) deposition, warming, and elevated CO2] on primary productivity and on the biogeochemistry of carbon (C), N, and phosphorus (P) across different terrestrial ecosystems. Here, we capitalize on this large amount of information by performing a comprehensive meta‐analysis (>2000 case studies worldwide) to address how C:N:P stoichiometry of plants, soils, and soil microbial biomass might respond to individual vs. combined effects of the three global change drivers. Our results show that (i) individual effects of N addition and elevated CO2 on C:N:P stoichiometry are stronger than warming, (ii) combined effects of pairs of global change drivers (e.g., N addition + elevated CO2, warming + elevated CO2) on C:N:P stoichiometry were generally weaker than the individual effects of each of these drivers, (iii) additive interactions (i.e., when combined effects are equal to or not significantly different from the sum of individual effects) were more common than synergistic or antagonistic interactions, (iv) C:N:P stoichiometry of soil and soil microbial biomass shows high homeostasis under global change manipulations, and (v) C:N:P responses to global change are strongly affected by ecosystem type, local climate, and experimental conditions. Our study is one of the first to compare individual vs. combined effects of the three global change drivers on terrestrial C:N:P ratios using a large set of data. To further improve our understanding of how ecosystems might respond to future global change, long‐term ecosystem‐scale studies testing multifactor effects on plants and soils are urgently required across different world regions. 相似文献
936.
Dario Farina Andrea Blanchietti Marco Pozzo Roberto Merletti 《Journal of applied physiology》2004,97(2):545-555
The aim of this study was to interpret changes in experimentally recorded M waves with progressive motor unit (MU) activation based on simulation of the surface electromyogram. Activation order during transcutaneous electrical stimulation was analyzed by investigating M-wave average rectified value, spectral properties, and conduction velocity (CV) during electrically elicited contractions. M-waves were detected from the biceps brachii muscle of 10 healthy male subjects by a linear adhesive array of eight electrodes. Electrical stimulation was delivered to the motor point at either constant current intensity (40, 60, 80, and 100% of the supramaximal stimulation current) or with linearly increasing current. A model of surface electromyogram generation that varied activation order based on MU size and location was used to interpret the experimental results. From the experimental and model analysis, it was found that 1) MUs tended to be activated from low to high CV and from the superficial to the deep muscle layers with increasing transcutaneous electrical stimulation of the biceps brachii muscle, and 2) characteristic spectral frequencies of the M-wave were affected by many factors other than average CV (such as the activation order by MU location or the spread of the MU innervation zones and CVs), thus decreasing with a concomitant increase in CV during progressive MU activation. 相似文献
937.
Early in infection, pathogens encounter the outer wall of plant cells. Because pathogen hydrolases targeting the plant cell wall are well-known components of virulence, it has been assumed that wall disassembly by the plant itself also contributes to susceptibility, and now this has been established experimentally. Understanding how plant morphological and developmental remodeling and pathogen cell wall targeted virulence influence infections provides new perspectives about plant-pathogen interactions. The plant cell wall can be an effective physical barrier to pathogens, but also it is a matrix where many proteins involved in pathogen perception are delivered. By breaching the wall, a pathogen potentially reveals itself to the plant and activates responses, setting off events that might halt or limit its advance. 相似文献
938.
Andrea Porceddu Francesco Panara Ornella Calderini Lorna Molinari Paola Taviani Luisa Lanfaloni Carla Scotti Maria Carelli Laura Scaramelli Gianluca Bruschi Viviane Cosson Pascal Ratet Henri de Larembergue Gerard Duc Efisio Piano Sergio Arcioni 《BMC research notes》2008,1(1):129
Background
Medicago truncatula is a model species for legumes. Its functional genomics have been considerably boosted in recent years due to initiatives based both in Europe and US. Collections of mutants are becoming increasingly available and this will help unravel the genetic control of important traits for many species of legumes.Findings
Our report is on the production of three complementary mutant collections of the model species Medicago truncatula produced in Italy in the frame of a national genomic initiative. Well established strategies were used: Tnt1 mutagenesis, TILLING and activation tagging. Both forward and reverse genetics screenings proved the efficiency of the mutagenesis approaches adopted, enabling the isolation of interesting mutants which are in course of characterization. We anticipate that the reported collections will be complementary to the recently established functional genomics tools developed for Medicago truncatula both in Europe and in the United States.939.
Eva Terzibasi Dario Riccardo Valenzano Mauro Benedetti Paola Roncaglia Antonino Cattaneo Luciano Domenici Alessandro Cellerino 《PloS one》2008,3(12)
Background
A laboratory inbred strain of the annual fish Nothobranchius furzeri shows exceptionally short life expectancy and accelerated expression of age markers. In this study, we analyze new wild-derived lines of this short-lived species.Methodology/Principal Findings
We characterized captive survival and age-related traits in F1 and F2 offspring of wild-caught N. furzeri. Wild-derived N. furzeri lines showed expression of lipofuscin and neurodegeneration at age 21 weeks. Median lifespan in the laboratory varied from to 20 to 23 weeks and maximum lifespan from 25 to 32 weeks. These data demonstrate that rapid age-dependent decline and short lifespan are natural characteristics of this species. The N. furzeri distribution range overlaps with gradients in altitude and aridity. Fish from more arid habitats are expected to experience a shorter survival window in the wild. We tested whether captive lines stemming from semi-arid and sub-humid habitats differ in longevity and expression of age-related traits. We detected a clear difference in age-dependent cognitive decline and a slight difference in lifespan (16% for median, 15% for maximum lifespan) between these lines. Finally, we observed shorter lifespan and accelerated expression of age-related markers in the inbred laboratory strain compared to these wild-derived lines.Conclusions/Significance
Owing to large differences in aging phenotypes in different lines, N. furzeri could represent a model system for studying the genetic control of life-history traits in natural populations. 相似文献940.
Dilernia DA Jones L Rodriguez S Turk G Rubio AE Pampuro S Gomez-Carrillo M Bautista CT Bautista C Deluchi G Benetucci J Lasala MB Lourtau L Losso MH Perez H Cahn P Salomón H 《PloS one》2008,3(10):e3429