4,662 research outputs found
Bioactive potential of two marine picocyanobacteria belonging to Cyanobium and Synechococcus genera
Coccoid cyanobacteria produce a great variety of secondary metabolites, which may have useful properties, such as antibacterial, antiviral, anticoagulant or anticancer activities. These cyanobacterial metabolites have high ecological significance, and they could be considered responsible for the widespread occurrence of these microorganisms. Considering the great benefit derived from the identification of competent cyanobacteria for the extraction of bioactive compounds, two strains of picocyanobacteria (coccoid cyanobacteria < 3 ”m) (Cyanobium sp. ITAC108 and Synechococ-cus sp. ITAC107) isolated from the Mediterranean sponge Petrosia ficiformis were analyzed. The biological effects of organic and aqueous extracts from these picocyanobacteria toward the nauplii of Artemia salina, sea urchin embryos and human cancer lines (HeLa cells) were evaluated. Methanolic and aqueous extracts from the two strains strongly inhibited larval development; on the contrary, in ethyl acetate and hexane extracts, the percentage of anomalous embryos was low. Moreover, all the extracts of the two strains inhibited HeLa cell proliferation, but methanol extracts exerted the highest activity. Gas chromatographyâmass spectrometry analysis evidenced for the first time the presence of ÎČ-N-methylamino-L-alanine and microcystin in these picocyanobacteria. The strong cytotoxic activity observed for aqueous and methanolic extracts of these two cyanobacteria laid the foundation for the production of bioactive compounds of pharmacological interest
hMENA11a contributes to HER3-mediated resistance to PI3K inhibitors in HER2-overexpressing breast cancer cells.
Human Mena (hMENA), an actin regulatory protein of the ENA/VASP family, cooperates with ErbB receptor family signaling in breast cancer. It is overexpressed in high-risk preneoplastic lesions and in primary breast tumors where it correlates with HER2 overexpression and an activated status of AKT and MAPK. The concomitant overexpression of hMENA and HER2 in breast cancer patients is indicative of a worse prognosis. hMENA is expressed along with alternatively expressed isoforms, hMENA11a and hMENAÎv6 with opposite functions. A novel role for the epithelial-associated hMENA11a isoform in sustaining HER3 activation and pro-survival pathways in HER2-overexpressing breast cancer cells has been identified by reverse phase protein array and validated in vivo in a series of breast cancer tissues. As HER3 activation is crucial in mechanisms of cell resistance to PI3K inhibitors, we explored whether hMENA11a is involved in these resistance mechanisms. The specific hMENA11a depletion switched off the HER3-related pathway activated by PI3K inhibitors and impaired the nuclear accumulation of HER3 transcription factor FOXO3a induced by PI3K inhibitors, whereas PI3K inhibitors activated hMENA11a phosphorylation and affected its localization. At the functional level, we found that hMENA11a sustains cell proliferation and survival in response to PI3K inhibitor treatment, whereas hMENA11a silencing increases molecules involved in cancer cell apoptosis. As shown in three-dimensional cultures, hMENA11a contributes to resistance to PI3K inhibition because its depletion drastically reduced cell viability upon treatment with PI3K inhibitor BEZ235. Altogether, these results indicate that hMENA11a in HER2-overexpressing breast cancer cells sustains HER3/AKT axis activation and contributes to HER3-mediated resistance mechanisms to PI3K inhibitors. Thus, hMENA11a expression can be proposed as a marker of HER3 activation and resistance to PI3K inhibition therapies, to select patients who may benefit from these combined targeted treatments. hMENA11a activity could represent a new target for antiproliferative therapies in breast cancer
Positioning by multicell fingerprinting in urban NB-IoT networks
Narrowband Internet of Things (NB-IoT) has quickly become a leading technology in the deployment of IoT systems and services, owing to its appealing features in terms of coverage and energy efficiency, as well as compatibility with existing mobile networks. Increasingly, IoT services and applications require location information to be paired with data collected by devices; NB-IoT still lacks, however, reliable positioning methods. Time-based techniques inherited from long-term evolution (LTE) are not yet widely available in existing networks and are expected to perform poorly on NB-IoT signals due to their narrow bandwidth. This investigation proposes a set of strategies for NB-IoT positioning based on fingerprinting that use coverage and radio information from multiple cells. The proposed strategies were evaluated on two large-scale datasets made available under an open-source license that include experimental data from multiple NB-IoT operators in two large cities: Oslo, Norway, and Rome, Italy. Results showed that the proposed strategies, using a combination of coverage and radio information from multiple cells, outperform current state-of-the-art approaches based on single cell fingerprinting, with a minimum average positioning error of about 20 m when using data for a single operator that was consistent across the two datasets vs. about 70 m for the current state-of-the-art approaches. The combination of data from multiple operators and data smoothing further improved positioning accuracy, leading to a minimum average positioning error below 15 m in both urban environments
Proanthocyanidins from \u3cem\u3eHedysarum, Lotus\u3c/em\u3e and \u3cem\u3eOnobrychis\u3c/em\u3e spp. Growing in Sardinia and Sicily and Their Antioxidant Activity
Proanthocyanidins (PA), or condensed tannins, are a class of natural polyphenolic compounds, occurring in numerous plant species, including a number of economically significant forage legumes. These compounds are polymers of flavan-3-ols, and typically contain from 2 to 20 units. Their biological significance is still being debated and, in recent years, a great deal of attention has been focused on their role in ruminant nutrition. Evidence has indicated that PA, in a moderate concentration (0.5-5% DM), may have considerable importance in protecting dietary proteins against microbial degradation in the rumen, and in preventing bloat. The antioxidant activity (AA) is also an important feature for animal well-being (Barry & McNabb, 1999). In order to study the PA content related to the antioxidant activity, samples of Hedysarum, Lotus and Onobrychis spp. from Mediterranean environments have been considered and investigated
The Neuropsychological Profile of Attention Deficits of Patients with Obstructive Sleep Apnea: An Update on the Daytime Attentional Impairment
none7noAbstract: Introduction: Patients with obstructive sleep apnea (OSA) suffer from several neurocognitive
disturbances. One of the neuropsychological processes most investigated in OSA patients is attention,
but the results have been controversial. Here, we update the attention profile of OSA patients with
the final aim to improve attention assessment, with a possible impact on clinical and medical-legal
practices, in terms of which attention subdomains and parameters need consideration and which one
is a high-risk OSA phenotype for attention dysfunctions. Method: For this purpose, we assessed
32 previously untreated OSA patients (26 men and 6 women) under 65 years of age (mean age
53.2 ± 7.3; mean education level 10.4 ± 3.4 years) suffering from moderate to severe sleep apnea and
hypopnea (mean apnea-hypopnea index (AHI) 45.3 ± 22.9, range 16.1â69.6). A control group of
34 healthy participants matched with OSA patients for age, education level, and general cognitive
functioning were also enrolled. The OSA patients and healthy participants were tested through an
extensive computerized battery (Test of Attentional Performance, TAP) that evaluated intensive (i.e.,
alertness and vigilance) and selective (i.e., divided and selective) dimensions of attention and returned
different outcome parameters (i.e., reaction time, stability of performance, and various types of
errors). Data analysis: The data were analyzed by ANCOVA which compared the speed and accuracy
performance of the OSA and control participants (cognitive reserve was treated as a covariate).
The possible mechanisms underlying attention deficits in OSA patients were examined through
correlation analysis among AHI, oxygenation parameters, sleepiness scores, and TAP outcomes and by
comparing the following three phenotypes of patients: severe OSA and severe nocturnal desaturators
(AHI++D+), severe OSA nondesaturators (AHI++Dâ), and moderate OSA nondesaturators (AHI+Dâ).
Results: The results suggest that the OSA patients manifest deficits in both intensive and selective
attention processes and that reaction time (RT) alone is ineffective for detecting and characterizing
their problems, for which error analysis and stability of performance also have to be considered.
Patients with severe OSA and severe hypoxemia underperformed on alertness and vigilance attention
subtests. Conclusions: The data suggest the importance of evaluating attention deficits among OSA
patients through several parameters (including performance instability). Moreover, the data suggest
a multifaceted mechanism underlying attention dysfunction in OSA patients.openAngelelli P., Macchitella L., Toraldo D.M., Abbate E., Marinelli C.V., Ariglian M., De Benedetto M.Angelelli, P.; Macchitella, L.; Toraldo, D. M.; Abbate, E.; Marinelli, C. V.; Ariglian, M.; De Benedetto, M
Diffused capacitance-based sensing for hydric control and watering optimization
Soil moisture measurements are essential especially in the agricultural field, where it is crucial to guarantee that the optimal amount of water is provided to the cultivations. Most soil moisture measurement systems are local sensors; hence, a multitude of sensors must be distributed all over the field to obtain a comprehensive picture of the soil condition. Starting from these considerations, the present work addresses the feasibility of employing diffused sensing elements (in a wire-like configuration) for sensing soil moisture variations, based on capacitance measurements. To this purpose, for a preliminary validation of the proposed methodology, several experiments were carried out, thus identifying the suitable setup configurations and the potential of the method
Bioactive composition and sensory evaluation of innovative spaghetti supplemented with free or α-cyclodextrin chlatrated pumpkin oil extracted by supercritical CO2
The feasibility of producing durum wheat pasta enriched with a lipophilic phytocomplex, extracted using supercritical carbon dioxide (SC-CO2), from ripe pumpkin, as free oil or as ready-to-mix oil/α-cyclodextrins (α-CDs)powder, was explored. Four types of pasta were prepared: (i)control spaghetti (S-CTRL); (ii)spaghetti supplemented with α-CDs (S-α-CD); (iii)spaghetti supplemented with pumpkin oil (S-Oil)and (iv)spaghetti supplemented with the pumpkin oil/α-CD powder (S-Oil/α-CD). The chemical, antioxidant, textural and sensory attributes of the different pasta were evaluated and compared. S-Oil and S-Oil/α-CD spaghetti were significantly enriched with phytosterols, squalene, carotenoids, tocochromanols and unsaturated fatty acids. Spaghetti containing α-CDs were slightly improved in terms of fiber content. Oil chlatration increased the stability of some bioactives during pasta production and ameliorated poor textural and sensory characteristics of the cooked spaghetti compared with S-Oil sample. S-Oil/α-CD spaghetti might be accepted by customers, if the potential health benefits were also explained
Ergodicity criteria for non-expanding transformations of 2-adic spheres
In the paper, we obtain necessary and sufficient conditions for ergodicity
(with respect to the normalized Haar measure) of discrete dynamical systems
on 2-adic spheres of radius
, , centered at some point from the ultrametric space of
2-adic integers . The map is
assumed to be non-expanding and measure-preserving; that is, satisfies a
Lipschitz condition with a constant 1 with respect to the 2-adic metric, and
preserves a natural probability measure on , the Haar measure
on which is normalized so that
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