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排序方式: 共有588条查询结果,搜索用时 31 毫秒
471.
Daniela Di Paolo Fabio Pastorino Chiara Brignole Maria Valeria Corrias Laura Emionite Michele Cilli Roberto Tamma Leslie Priddy Adriana Amaro Davide Ferrari Roberto Marotta Elisa Ferretti Ulrich Pfeffer Domenico Ribatti Angela Rita Sementa David Brown Naohiko Ikegaki Hiroyuki Shimada Mirco Ponzoni Patrizia Perri 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(20)
Neuroblastoma (NB) tumor substantially contributes to childhood cancer mortality. The design of novel drugs targeted to specific molecular alterations becomes mandatory, especially for high‐risk patients burdened by chemoresistant relapse. The dysregulated expression of MYCN, ALK, and LIN28B and the diminished levels of miR‐34a and let‐7b are oncogenic in NB. Due to the ability of miRNA‐mimics to recover the tumor suppression functions of miRNAs underexpressed into cancer cells, safe and efficient nanocarriers selectively targeted to NB cells and tested in clinically relevant mouse models are developed. The technology exploits the nucleic acids negative charges to build coated‐cationic liposomes, then functionalized with antibodies against GD2 receptor. The replenishment of miR‐34a and let‐7b by NB‐targeted nanoparticles, individually and more powerfully in combination, significantly reduces cell division, proliferation, neoangiogenesis, tumor growth and burden, and induces apoptosis in orthotopic xenografts and improves mice survival in pseudometastatic models. These functional effects highlight a cooperative down‐modulation of MYCN and its down‐stream targets, ALK and LIN28B, exerted by miR‐34a and let‐7b that reactivate regulatory networks leading to a favorable therapeutic response. These findings demonstrate a promising therapeutic efficacy of miR‐34a and let‐7b combined replacement and support its clinical application as adjuvant therapy for high‐risk NB patients. 相似文献
472.
Miriam Buttacavoli Gianluca Di Cara Elena Roz Ida Pucci-Minafra Salvatore Feo Patrizia Cancemi 《International journal of molecular sciences》2021,22(22)
Colorectal cancer (CRC) develops by genetic and epigenetic alterations. However, the molecular mechanisms underlying metastatic dissemination remain unclear and could benefit from multi-omics investigations of specific protein families. Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in ECM remodeling and the processing of bioactive molecules. Increased MMP expression promotes the hallmarks of tumor progression, including angiogenesis, invasion, and metastasis, and is correlated with a shortened survival. Nevertheless, the collective role and the possible coordination of MMP members in CRC are poorly investigated. Here, we performed a multi-omics analysis of MMP expression in CRC using data mining and experimental investigations. Several databases were used to deeply mine different expressions between tumor and normal tissues, the genetic and epigenetic alterations, the prognostic value as well as the interrelationships with tumor immune-infiltrating cells (TIICs). A special focus was placed on to MMP2 and MMP9: their expression was correlated with immune markers and the interaction network of co-expressed genes disclosed their implication in epithelial to mesenchymal transition (EMT) and immune response. Finally, the activity levels of MMP2 and MMP9 in a cohort of colon cancer samples, including tissues and the corresponding sera, was also investigated by zymography. Our findings suggested that MMPs could have a high potency, as they are targeted in colon cancer, and might serve as novel biomarkers, especially for their involvement in the immune response. However, further studies are needed to explore the detailed biological functions and molecular mechanisms of MMPs in CRC, also in consideration of their expression and different regulation in several tissues. 相似文献
473.
Carlo Zambonelli Patrizia Passarelli Sandra Rainieri Luca Bertolini Paolo Giudici Lorena Castellari 《Journal of the science of food and agriculture》1997,74(1):7-12
Hybrids obtained by crossing cryotolerant and non-cryotolerant strains of Saccharomyces were studied. The hybrids, all sterile, are more vigorous and competitive than their parents over a wide range of temperatures. They develop well both at low temperatures (6°C) and at high temperatures (36°C) and have an optimum temperature range of 27–33°C. Minor fermentation compounds are always produced in medium quantities (while the parent are highly differentiated in this regard): this is true of glycerol, succinic acid, acetic acid and 2-phenylethanol. The hybrids are able to synthesise malic acid but to a lesser extent than their cryotolerant parents. The results regarding cryotolerant and non-cryotolerant parents and their respective hybrids were processed using a one-way analysis of variance and exhibited significant differences. The hybrids are of great enological interest both for their characteristics of competitiveness and stability and for their fermentation products. © 1997 SCI. 相似文献
474.
Francesca Ferrara Mascia Benedusi Franco Cervellati Maddalena Sguizzato Leda Montesi Agnese Bondi Markus Drechsler Walter Pula Giuseppe Valacchi Elisabetta Esposito 《International journal of molecular sciences》2022,23(15)
In this study, transethosomes were investigated as potential delivery systems for dimethyl fumarate. A formulative study was performed investigating the effect of the composition of transethosomes on the morphology and size of vesicles, as well as drug entrapment capacity, using cryogenic transmission electron microscopy, photon correlation spectroscopy, and HPLC. The stability of vesicles was evaluated, both for size increase and capability to control the drug degradation. Drug release kinetics and permeability profiles were evaluated in vitro using Franz cells, associated with different synthetic membranes. The in vitro viability, as well as the capacity to improve wound healing, were evaluated in human keratinocytes. Transmission electron microscopy enabled the evaluation of transethosome uptake and intracellular fate. Based on the obtained results, a transethosome gel was further formulated for the cutaneous application of dimethyl fumarate, the safety of which was evaluated in vivo with a patch test. It was found that the phosphatidylcholine concentration affected vesicle size and lamellarity, influencing the capacity to control dimethyl fumarate’s chemical stability and release kinetics. Indeed, phosphatidylcholine 2.7% w/w led to multivesicular vesicles with 344 nm mean size, controlling the drug’s chemical stability for at least 90 days. Conversely, phosphatidylcholine 0.9% w/w resulted in 130 nm sized unilamellar vesicles, which maintained 55% of the drug over 3 months. These latest kinds of transethosomes were able to improve wound healing in vitro and were easily internalised by keratinocytes. The selected transethosome gel, loading 25 mg/mL dimethyl fumarate, was not irritant after cutaneous application under occlusion, suggesting its possible suitability in the treatment of wounds caused by diabetes mellitus or peripheral vascular diseases. 相似文献
475.
Alessandro Taloni Francis Allen Farrelly Giuseppe Pontillo Nikolaos Petsas Costanza Giannì Serena Ruggieri Maria Petracca Arturo Brunetti Carlo Pozzilli Patrizia Pantano Silvia Tommasin 《International journal of molecular sciences》2022,23(18)
Short-term disability progression was predicted from a baseline evaluation in patients with multiple sclerosis (MS) using their three-dimensional T1-weighted (3DT1) magnetic resonance images (MRI). One-hundred-and-eighty-one subjects diagnosed with MS underwent 3T-MRI and were followed up for two to six years at two sites, with disability progression defined according to the expanded-disability-status-scale (EDSS) increment at the follow-up. The patients’ 3DT1 images were bias-corrected, brain-extracted, registered onto MNI space, and divided into slices along coronal, sagittal, and axial projections. Deep learning image classification models were applied on slices and devised as ResNet50 fine-tuned adaptations at first on a large independent dataset and secondly on the study sample. The final classifiers’ performance was evaluated via the area under the curve (AUC) of the false versus true positive diagram. Each model was also tested against its null model, obtained by reshuffling patients’ labels in the training set. Informative areas were found by intersecting slices corresponding to models fulfilling the disability progression prediction criteria. At follow-up, 34% of patients had disability progression. Five coronal and five sagittal slices had one classifier surviving the AUC evaluation and null test and predicted disability progression (AUC > 0.72 and AUC > 0.81, respectively). Likewise, fifteen combinations of classifiers and axial slices predicted disability progression in patients (AUC > 0.69). Informative areas were the frontal areas, mainly within the grey matter. Briefly, 3DT1 images may give hints on disability progression in MS patients, exploiting the information hidden in the MRI of specific areas of the brain. 相似文献
476.
Giorgia Pellavio Patrizia Sommi Umberto Anselmi-Tamburini Maria Paola DeMichelis Stefania Coniglio Umberto Laforenza 《International journal of molecular sciences》2022,23(18)
Some aquaporins (AQPs) allow the diffusion of hydrogen peroxide (H2O2), the most abundant ROS, through the cell membranes. Therefore, the possibility of regulating the AQP-mediated permeability to H2O2, and thus ROS scavenging, appears particularly important for controlling the redox state of cells in physiological and pathophysiological conditions. Several compounds have been screened and characterized for this purpose. This study aimed to analyze the effect of cerium oxide nanoparticles (CNPs) presenting antioxidant activity on AQP functioning. HeLa cells express AQP3, 6, 8, and 11, able to facilitate H2O2. AQP3, 6, and 8 are expressed in the plasma membrane and intracellularly, while AQP11 resides only in intracellular structures. CNPs but not cerium ions treatment significantly increased the water and H2O2 permeability by interacting with AQP3, 6, and especially with AQP8. CNPs increased considerably the AQP-mediated water diffusion in cells with oxidative stress. Functional experiments with silenced HeLa cells revealed that CNPs increased the H2O2 diffusion mainly by modulating the AQP8 permeability but also the AQP3 and AQP6, even if to a lesser extent. Current findings suggest that CNPs represent a promising pharmaceutical agent that might potentially be used in numerous pathologies involving oxidative stress as tumors and neurodegenerative diseases. 相似文献
477.
Gloria Ravegnini Margherita Nannini Valentina Indio Cesar Serrano Francesca Gorini Annalisa Astolfi Aldo Di Vito Fabiana Morroni Maria Abbondanza Pantaleo Patrizia Hrelia Sabrina Angelini 《International journal of molecular sciences》2022,23(20)
Gastrointestinal stromal tumors (GISTs) harboring mutations in the PDGFRA gene occur in only about 5–7% of patients. The most common PDGFRA mutation is exon 18 D842V, which is correlated with specific clinico-pathological features compared to the other PDGFRA mutated GISTs. Herein, we present a miRNA expression profile comparison of PDGFRA D842V mutant GISTs and PDGFRA with mutations other than D842V (non-D842V). miRNA expression profiling was carried out on 10 patients using a TLDA miRNA array. Then, miRNA expression was followed by bioinformatic analysis aimed at evaluating differential expression, pathway enrichment, and miRNA-mRNA networks. We highlighted 24 differentially expressed miRNAs between D842V and non-D842V GIST patients. Pathway enrichment analysis showed that deregulated miRNAs targeted genes that are mainly involved in the immune response pathways. The miRNA-mRNA networks highlighted a signature of miRNAs/mRNA that could explain the indolent behavior of the D842V mutated GIST. The results highlighted a different miRNA fingerprint in PDGFRA D842V GISTs compared to non-D842Vmutated patients, which could explain the different biological behavior of this GIST subset. 相似文献
478.
Flora Salzano Martina Aulitto Gabriella Fiorentino Emilia Pedone Patrizia Contursi Danila Limauro 《International journal of molecular sciences》2022,23(22)
A thermo-acidophilic bacterium, Alicyclobacillus mali FL18, was isolated from a hot spring of Pisciarelli, near Naples, Italy; following genome analysis, a novel putative β-xylosidase, AmβXyl, belonging to the glycosyl hydrolase (GH) family 3 was identified. A synthetic gene was produced, cloned in pET-30a(+), and expressed in Escherichia coli BL21 (DE3) RIL. The purified recombinant protein, which showed a dimeric structure, had optimal catalytic activity at 80 °C and pH 5.6, exhibiting 60% of its activity after 2 h at 50 °C and displaying high stability (more than 80%) at pH 5.0–8.0 after 16 h. AmβXyl is mainly active on both para-nitrophenyl-β-D-xylopyranoside (KM 0.52 mM, kcat 1606 s−1, and kcat/KM 3088.46 mM−1·s−1) and para-nitrophenyl-α-L-arabinofuranoside (KM 10.56 mM, kcat 2395.8 s−1, and kcat/KM 226.87 mM−1·s−1). Thin-layer chromatography showed its ability to convert xylooligomers (xylobiose and xylotriose) into xylose, confirming that AmβXyl is a true β-xylosidase. Furthermore, no inhibitory effect on enzymatic activity by metal ions, detergents, or EDTA was observed except for 5 mM Cu2+. AmβXyl showed an excellent tolerance to organic solvents; in particular, the enzyme increased its activity at high concentrations (30%) of organic solvents such as ethanol, methanol, and DMSO. Lastly, the enzyme showed not only a good tolerance to inhibition by xylose, arabinose, and glucose, but was activated by 0.75 M xylose and up to 1.5 M by both arabinose and glucose. The high tolerance to organic solvents and monosaccharides together with other characteristics reported above suggests that AmβXyl may have several applications in many industrial fields. 相似文献
479.
Alessio Alesci Gioele Capillo Doaa M. Mokhtar Angelo Fumia Roberta DAngelo Patrizia Lo Cascio Marco Albano Maria Cristina Guerrera Ramy K. A. Sayed Nunziacarla Span Simona Pergolizzi Eugenia Rita Lauriano 《International journal of molecular sciences》2022,23(22)
The amphibious teleost Giant mudskipper (Periophthalmodon schlosseri, Pallas 1770) inhabit muddy plains and Asian mangrove forests. It spends more than 90% of its life outside of the water, using its skin, gills, and buccal-pharyngeal cavity mucosa to breathe in oxygen from the surrounding air. All vertebrates have been found to have mast cells (MCs), which are part of the innate immune system. These cells are mostly found in the mucous membranes of the organs that come in contact with the outside environment. According to their morphology, MCs have distinctive cytoplasmic granules that are released during the degranulation process. Additionally, these cells have antimicrobial peptides (AMPs) that fight a variety of infections. Piscidins, hepcidins, defensins, cathelicidins, and histonic peptides are examples of fish AMPs. Confocal microscopy was used in this study to assess Piscidin1 expression in Giant Mudskipper branchial MCs. Our results demonstrated the presence of MCs in the gills is highly positive for Piscidin1. Additionally, colocalized MCs labeled with TLR2/5-HT and Piscidin1/5-HT supported our data. The expression of Piscidin1 in giant mudskipper MCs highlights the involvement of this peptide in the orchestration of teleost immunity, advancing the knowledge of the defense system of this fish. 相似文献
480.
Francesco Sestili Benedetta Margiotta Patrizia Vaccino Salvatore Moscaritolo Debora Giorgi Sergio Lucretti Samuela Palombieri Stefania Masci Domenico Lafiandra 《International journal of molecular sciences》2020,21(22)
A bread wheat line (N11) and a disomic 2D(2R) substitution triticale line were crossed and backrossed four times. At each step electrophoretic selection for the seeds that possessed, simultaneously, the complete set of high molecular weight glutenin subunits of N11 and the two high molecular weight secalins of rye, present in the 2D(2R) line, was carried out. Molecular cytogenetic analyses of the BC4F8 generation revealed that the selection carried out produced a disomic addition line (2n = 44). The pair of additional chromosomes consisted of the long arm of chromosome 1R (1RL) from rye fused with the satellite body of the wheat chromosome 6B. Rheological analyses revealed that the dough obtained by the new addition line had higher quality characteristics when compared with the two parents. The role of the two additional high molecular weight secalins, present in the disomic addition line, in influencing improved dough characteristics is discussed. 相似文献