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排序方式: 共有116条查询结果,搜索用时 15 毫秒
31.
Lorenza Viola 《Journal of Modern Optics》2013,60(16-18):2357-2367
Abstract I address the current status of dynamical decoupling techniques in terms of required control resources and feasibility. Based on recent advances in both improving the theoretical design and assessing the control performance for specific noise models, I argue that significant progress may still be possible on the road to implementing decoupling under realistic constraints. 相似文献
32.
Pamela Vernocchi Tommaso Gili Federica Conte Federica Del Chierico Giorgia Conta Alfredo Miccheli Andrea Botticelli Paola Paci Guido Caldarelli Marianna Nuti Paolo Marchetti Lorenza Putignani 《International journal of molecular sciences》2020,21(22)
Several studies in recent times have linked gut microbiome (GM) diversity to the pathogenesis of cancer and its role in disease progression through immune response, inflammation and metabolism modulation. This study focused on the use of network analysis and weighted gene co-expression network analysis (WGCNA) to identify the biological interaction between the gut ecosystem and its metabolites that could impact the immunotherapy response in non-small cell lung cancer (NSCLC) patients undergoing second-line treatment with anti-PD1. Metabolomic data were merged with operational taxonomic units (OTUs) from 16S RNA-targeted metagenomics and classified by chemometric models. The traits considered for the analyses were: (i) condition: disease or control (CTRLs), and (ii) treatment: responder (R) or non-responder (NR). Network analysis indicated that indole and its derivatives, aldehydes and alcohols could play a signaling role in GM functionality. WGCNA generated, instead, strong correlations between short-chain fatty acids (SCFAs) and a healthy GM. Furthermore, commensal bacteria such as Akkermansia muciniphila, Rikenellaceae, Bacteroides, Peptostreptococcaceae, Mogibacteriaceae and Clostridiaceae were found to be more abundant in CTRLs than in NSCLC patients. Our preliminary study demonstrates that the discovery of microbiota-linked biomarkers could provide an indication on the road towards personalized management of NSCLC patients. 相似文献
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34.
Chiara Pellegrino Maria Penelope De Santo Lorenza Spina Federica Ciuchi 《Advanced functional materials》2021,31(11):2010394
Chirality emergence in biological systems is common but the chiral expression from the molecular to macroscopic level in water-based systems is poorly understood. Among water-based systems, chromonic liquid crystals have recently received a lot of attention due to the spontaneous chirality they show when confined in curved geometries. Confinement of chiral-induced chromonics is not trivial since they are three component systems whose time stability is a delicate thermodynamic balance. In this work, a well-defined periodic Frank–Pryce texture, typical of chiral thermotropic liquid crystals, is observed in microspheres of a chiral induced chromonic embedded in a poly(dimethylsiloxane) matrix. This texture slowly degrades in time and a possible mechanism behind the degradation process is suggested via X-ray diffraction and atomic force microscopy measurements on thin chromonic films. To stabilize this texture and to control the structure periodicity, cations are added to the three components system in an attempt to tune the non-covalent interactions between molecules and supramolecular stacks. The study of the effects of this addition allows for better insight into the molecular interactions that occur in the chiral induced mesophase. This is a crucial point in view of possible biocompatible technological applications. 相似文献
35.
PA Romitti AC Lidral RG Munger S Daack-Hirsch TL Burns JC Murray 《Canadian Metallurgical Quarterly》1999,59(1):39-50
Previous studies suggest that the relationship between genes and nonsyndromic cleft lip +/- cleft palate (CLP) or cleft palate only (CP) may be modified by the environment. Using data from a population-based case-control study, we examined allelic variants for three genes, i.e., transforming growth factor alpha (TGFA), transforming growth factor beta 3 (TGFB3), and Msh (Drosophila) homeobox homolog 1 (MSX1), and their interactions with two exposures during pregnancy (maternal cigarette smoking and alcohol consumption) as risk factors for CLP and CP. For each cleft phenotype, risk estimates associated with most allelic variants tended to be near unity. Risk estimates for maternal smoking (> or = 10 cigarettes/day) were significantly elevated for CP and were most elevated among infants with allelic variants at the TGFB3 or MSX1 sites. By comparison, risk estimates for maternal alcohol consumption (> or = 4 drinks/month) were significantly elevated for CLP and were most elevated among infants with allelic variants at the MSX1 site. Our results suggest that development of CLP and CP may be influenced independently by maternal exposures but more significantly by interaction of such exposures and specific allelic variants. 相似文献
36.
Carla Vaz Ferreira Débora Rodrigues Siqueira Mírian Romitti Lucieli Ceolin Beatriz Assis Brasil Luise Meurer Clarissa Capp Ana Luiza Maia 《International journal of molecular sciences》2014,15(4):5323-5336
Pheochromocytoma (PHEO), a rare catecholamine producing tumor arising from the chromaffin cells, may occurs sporadically (76%–80%) or as part of inherited syndromes (20%–24%). Angiogenesis is a fundamental step in tumor proliferation and vascular endothelial growth factor (VEGF-A) is the most well-characterized angiogenic factor. The role of angiogenic markers in PHEO is not fully understood; investigations were therefore made to evaluate the expression of VEGF-A and its receptors in PHEO and correlate to clinical parameters. Twenty-nine samples of PHEO were evaluated for VEGF-A, VEGF receptor-1 (VEGFR-1) VEGFR-2 expression and microvessel density (MVD) by immunohistochemistry. Clinical data were reviewed in medical records. The mean age of patients was 38 ± 14 years, and 69% were woman. VEGF-A, VEGFR-1 and VEGFR-2 staining were detected in nearly all PHEO samples. No significant correlation was observed between VEGF-A, VEGFR-1, VEGFR-2 expression or MVD and age at diagnosis, tumor size or sporadic and hereditary PHEO. However, the levels of expression of these molecules were significantly higher in malignant PHEO samples (p = 0.027, p = 0.003 and p = 0.026, respectively).VEGF-A and its receptors were shown to be up-regulated in malignant PHEO, suggesting that these molecules might be considered as therapeutic targets for unresectable or metastatic tumors. 相似文献
37.
Lorenza Giupponi Ramon Agustí Jordi Pérez-Romero Oriol Sallent 《Mobile Networks and Applications》2006,11(6):825-846
Inter-working and convergence of heterogeneous wireless networks are paving the way to scenarios in which end users will be
capable of using simultaneously services through different Radio Access Technologies (RATs), by means of reconfigurable mobile
terminals and different network elements. In order to exploit the potential of these heterogeneous networks scenarios, optimal
RAT selection and resource utilization mechanisms are required. As a result, the heterogeneous networks are introducing a
new dimension to the Radio Resource Management (RRM) problem, so that new algorithms dealing with the dissimilarities and
complementarities of the multiple RATs from a joint perspective have to be considered. In this sense, this paper proposes
a Joint Radio Resource Management (JRRM) strategy in a multi-RAT, multicellular and multiservice scenario. An approach based
on Fuzzy Neural methodology is presented. Firstly, the way how the proposed Fuzzy Neural framework deals with the multiservice
allocation in a heterogeneous scenario is presented. A reinforcement learning algorithm based on neural networks allows guaranteeing
a multidimensional QoS focusing on those QoS requirements which mainly affect the user perception of the service. In addition
to this, the performances obtained by the Fuzzy Neural JRRM for both real-time and non real-time services, are compared to
the ones offered by alternative JRRM strategies. Secondly, special attention is paid to real-time services and to mechanisms
to improve their performances. An approach based on predicting future JRRM decisions and on accordingly reserving radio resources
for handoff calls is presented. Simulation results will show improvements in terms of both new connection blocking and handoff
call dropping probabilities. Finally, the full set of results provides the sufficient insight into the problem to allow stating
that the present Fuzzy Neural framework can be a firm candidate for JRRM.
相似文献
Oriol SallentEmail: |
38.
In this paper we define and characterize the process of developing a real-world Machine Learning application, with its difficulties and relevant issues, distinguishing it from the popular practice of exploiting ready-to-use data sets. To this aim, we analyze and summarize the lessons learned from applying Machine Learning techniques to a variety of problems. We believe that these lessons, though primarily based on our personal experience, can be generalized to a wider range of situations and are supported by the reported experiences of other researchers. 相似文献
39.
Lorenza Brocca Maira Rossi Monica Canepari Roberto Bottinelli Maria Antonietta Pellegrino 《International journal of molecular sciences》2022,23(1)
A large set of FoxOs-dependent genes play a primary role in controlling muscle mass during hindlimb unloading. Mitochondrial dysfunction can modulate such a process. We hypothesized that endurance exercise before disuse can protect against disuse-induced muscle atrophy by enhancing peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) expression and preventing mitochondrial dysfunction and energy-sensing AMP-activated protein kinase (AMPK) activation. We studied cross sectional area (CSA) of muscle fibers of gastrocnemius muscle by histochemistry following 1, 3, 7, and 14 days of hindlimb unloading (HU). We used Western blotting and qRT-PCR to study mitochondrial dynamics and FoxOs-dependent atrogenes’ expression at 1 and 3 days after HU. Preconditioned animals were submitted to moderate treadmill exercise for 7 days before disuse. Exercise preconditioning protected the gastrocnemius from disuse atrophy until 7 days of HU. It blunted alterations in mitochondrial dynamics up to 3 days after HU and the expression of most atrogenes at 1 day after disuse. In preconditioned mice, the activation of atrogenes resumed 3 days after HU when mitochondrial dynamics, assessed by profusion and pro-fission markers (mitofusin 1, MFN1, mitofusin 2, MFN2, optic atrophy 1, OPA1, dynamin related protein 1, DRP1 and fission 1, FIS1), PGC1α levels, and AMPK activation were at a basal level. Therefore, the normalization of mitochondrial dynamics and function was not sufficient to prevent atrogenes activation just a few days after HU. The time course of sirtuin 1 (SIRT1) expression and content paralleled the time course of atrogenes’ expression. In conclusion, seven days of endurance exercise counteracted alterations of mitochondrial dynamics and the activation of atrogenes early into disuse. Despite the normalization of mitochondrial dynamics, the effect on atrogenes’ suppression died away within 3 days of HU. Interestingly, muscle protection lasted until 7 days of HU. A longer or more intense exercise preconditioning may prolong atrogenes suppression and muscle protection. 相似文献
40.
Lorenza Pastorino Bruna Dalmasso Eleonora Allavena Irene Vanni Filippo Ugolini Gianna Baroni Michela Croce Antonio Guadagno Francesco Cabiddu Virginia Andreotti William Bruno Gabriele Zoppoli Lorenzo Ferrando Enrica Teresa Tanda Francesco Spagnolo Chiara Menin Rosaria Gangemi Daniela Massi Paola Ghiorzo 《International journal of molecular sciences》2022,23(24)
ATM germline pathogenic variants were recently found enriched in high-risk melanoma patients. However, ATM loss of heterozygosity (LOH) has never been investigated in melanoma and, therefore, a causal association with melanoma development has not been established yet. The purpose of this study was to functionally characterize 13 germline ATM variants found in high-risk melanoma patients—and classified by in silico tools as pathogenic, uncertain significance, or benign—using multiple assays evaluating ATM/pATM expression and/or LOH in melanoma tissues and cell lines. We assessed ATM status by Immunohistochemistry (IHC), Western Blot, Whole-Exome Sequencing/Copy Number Variation analysis, and RNA sequencing, supported by Sanger sequencing and microsatellite analyses. For most variants, IHC results matched those obtained with in silico classification and LOH analysis. Two pathogenic variants (p.Ser1135_Lys1192del and p.Ser1993ArgfsTer23) showed LOH and complete loss of ATM activation in melanoma. Two variants of unknown significance (p.Asn358Ile and p.Asn796His) showed reduced expression and LOH, suggestive of a deleterious effect. This study, showing a classic two-hit scenario in a well-known tumor suppressor gene, supports the inclusion of melanoma in the ATM-related cancer spectrum. 相似文献