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排序方式: 共有1220条查询结果,搜索用时 15 毫秒
981.
Valentina Perricone Tobias B. Grun Francesco Rendina Francesco Marmo Maria Daniela Candia Carnevali Michal Kowalewski Angelo Facchini Mario De Stefano Luigia Santella Carla Langella Alessandra Micheletti 《Journal of the Royal Society Interface》2022,19(193)
Repeated polygonal patterns are pervasive in natural forms and structures. These patterns provide inherent structural stability while optimizing strength-per-weight and minimizing construction costs. In echinoids (sea urchins), a visible regularity can be found in the endoskeleton, consisting of a lightweight and resistant micro-trabecular meshwork (stereom). This foam-like structure follows an intrinsic geometrical pattern that has never been investigated. This study aims to analyse and describe it by focusing on the boss of tubercles—spine attachment sites subject to strong mechanical stresses—in the common sea urchin Paracentrotus lividus. The boss microstructure was identified as a Voronoi construction characterized by 82% concordance to the computed Voronoi models, a prevalence of hexagonal polygons, and a regularly organized seed distribution. This pattern is interpreted as an evolutionary solution for the construction of the echinoid skeleton using a lightweight microstructural design that optimizes the trabecular arrangement, maximizes the structural strength and minimizes the metabolic costs of secreting calcitic stereom. Hence, this identification is particularly valuable to improve the understanding of the mechanical function of the stereom as well as to effectively model and reconstruct similar structures in view of future applications in biomimetic technologies and designs. 相似文献
982.
Laura Lupini Roberta Roncarati Lorenzo Belluomini Federica Lancia Cristian Bassi Lucilla DAbundo Angelo Michilli Paola Guerriero Alessandra Fasano Elisa Tiberi Andrea Salamone Donato Michele Cosi Elena Saccenti Valentina Tagliatti Iva Maestri Silvia Sabbioni Stefano Volinia Roberta Gaf Giovanni Lanza Antonio Frassoldati Massimo Negrini 《International journal of molecular sciences》2022,23(15)
Liquid biopsy has advantages over tissue biopsy, but also some technical limitations that hinder its wide use in clinical applications. In this study, we aimed to evaluate the usefulness of liquid biopsy for the clinical management of patients with advanced-stage oncogene-addicted non-small-cell lung adenocarcinomas. The investigation was conducted on a series of cases—641 plasma samples from 57 patients—collected in a prospective consecutive manner, which allowed us to assess the benefits and limitations of the approach in a real-world clinical context. Thirteen samples were collected at diagnosis, and the additional samples during the periodic follow-up visits. At diagnosis, we detected mutations in ctDNA in 10 of the 13 cases (77%). During follow-up, 36 patients progressed. In this subset of patients, molecular analyses of plasma DNA/RNA at progression revealed the appearance of mutations in 29 patients (80.6%). Mutations in ctDNA/RNA were typically detected an average of 80 days earlier than disease progression assessed by RECIST or clinical evaluations. Among the cases positive for mutations, we observed 13 de novo mutations, responsible for the development of resistance to therapy. This study allowed us to highlight the advantages and disadvantages of liquid biopsy, which led to suggesting algorithms for the use of liquid biopsy analyses at diagnosis and during monitoring of therapy response. 相似文献
983.
Denisa Alexandra Florea Valentina Grumezescu Alexandra Ctlina Bîrc Bogdan tefan Vasile Mihaela Muat Cristina Chircov Miruna S. Stan Alexandru Mihai Grumezescu Ecaterina Andronescu Mariana Carmen Chifiriuc 《International journal of molecular sciences》2022,23(14)
Bone disorders and traumas represent a common type of healthcare emergency affecting men and women worldwide. Since most of these diseases imply surgery, frequently complicated by exogenous or endogenous infections, there is an acute need for improving their therapeutic approaches, particularly in clinical conditions requiring orthopedic implants. Various biomaterials have been investigated in the last decades for their potential to increase bone regeneration and prevent orthopedic infections. The present study aimed to develop a series of MAPLE-deposited coatings composed of magnesium phosphate (Mg3(PO4)2) and silver nanoparticles (AgNPs) designed to ensure osteoblast proliferation and anti-infective properties simultaneously. Mg3(PO4)2 and AgNPs were obtained through the cooling bath reaction and chemical reduction, respectively, and then characterized through X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and Selected Area Electron Diffraction (SAED). Subsequently, the obtained coatings were evaluated by Infrared Microscopy (IRM), Fourier-Transform Infrared Spectroscopy (FT-IR), and Scanning Electron Microscopy (SEM). Their biological properties show that the proposed composite coatings exhibit well-balanced biocompatibility and antibacterial activity, promoting osteoblasts viability and proliferation and inhibiting the adherence and growth of Staphylococcus aureus and Pseudomonas aeruginosa, two of the most important agents of orthopedic implant-associated infections. 相似文献
984.
985.
Valentina Ceccarelli Ilaria Barchetta Flavia Agata Cimini Laura Bertoccini Caterina Chiappetta Danila Capoccia Raffaella Carletti Claudio Di Cristofano Gianfranco Silecchia Mario Fontana Frida Leonetti Andrea Lenzi Marco Giorgio Baroni Eugenio Barone Maria Gisella Cavallo 《International journal of molecular sciences》2020,21(23)
Biliverdin reductase A (BVR-A) is an enzyme involved in the regulation of insulin signalling. Knockout (KO) mice for hepatic BVR-A, on a high-fat diet, develop more severe glucose impairment and hepato-steatosis than the wild type, whereas loss of adipocyte BVR-A is associated with increased visceral adipose tissue (VAT) inflammation and adipocyte size. However, BVR-A expression in human VAT has not been investigated. We evaluated BVR-A mRNA expression levels by real-time PCR in the intra-operative omental biopsy of 38 obese subjects and investigated the association with metabolic impairment, VAT dysfunction, and biopsy-proven non-alcoholic fatty liver disease (NAFLD). Individuals with lower VAT BVR-A mRNA levels had significantly greater VAT IL-8 and Caspase 3 expression than those with higher BVR-A. Lower VAT BVR-A mRNA levels were associated with an increased adipocytes’ size. An association between lower VAT BVR-A expression and higher plasma gamma-glutamyl transpeptidase was also observed. Reduced VAT BVR-A was associated with NAFLD with an odds ratio of 1.38 (95% confidence interval: 1.02–1.9; χ2 test) and with AUROC = 0.89 (p = 0.002, 95% CI = 0.76–1.0). In conclusion, reduced BVR-A expression in omental adipose tissue is associated with VAT dysfunction and NAFLD, suggesting a possible involvement of BVR-A in the regulation of VAT homeostasis in presence of obesity. 相似文献
986.
Angela Serena Maione Ilaria Stadiotti Chiara Assunta Pilato Gianluca Lorenzo Perrucci Valentina Saverio Valentina Catto Giulia Vettor Michela Casella Anna Guarino Gianluca Polvani Giulio Pompilio Elena Sommariva 《International journal of molecular sciences》2021,22(5)
Arrhythmogenic Cardiomyopathy (ACM) is characterized by the replacement of the myocardium with fibrotic or fibro-fatty tissue and inflammatory infiltrates in the heart. To date, while ACM adipogenesis is a well-investigated differentiation program, ACM-related fibrosis remains a scientific gap of knowledge. In this study, we analyze the fibrotic process occurring during ACM pathogenesis focusing on the role of cardiac mesenchymal stromal cells (C-MSC) as a source of myofibroblasts. We performed the ex vivo studies on plasma and right ventricular endomyocardial bioptic samples collected from ACM patients and healthy control donors (HC). In vitro studies were performed on C-MSC isolated from endomyocardial biopsies of both groups. Our results revealed that circulating TGF-β1 levels are significantly higher in the ACM cohort than in HC. Accordingly, fibrotic markers are increased in ACM patient-derived cardiac biopsies compared to HC ones. This difference is not evident in isolated C-MSC. Nevertheless, ACM C-MSC are more responsive than HC ones to TGF-β1 treatment, in terms of pro-fibrotic differentiation and higher activation of the SMAD2/3 signaling pathway. These results provide the novel evidence that C-MSC are a source of myofibroblasts and participate in ACM fibrotic remodeling, being highly responsive to ACM-characteristic excess TGF-β1. 相似文献
987.
Tiziana Bachetti Francesca Rosamilia Martina Bartolucci Giuseppe Santamaria Manuela Mosconi Serenella Sartori Maria Rosaria De Filippo Marco Di Duca Valentina Obino Stefano Avanzini Domenico Mavilio Simona Candiani Andrea Petretto Alessio Pini Prato Isabella Ceccherini Francesca Lantieri 《International journal of molecular sciences》2021,22(8)
Hirschsprung (HSCR) Associated Enterocolitis (HAEC) is a common life-threatening complication in HSCR. HAEC is suggested to be due to a loss of gut homeostasis caused by impairment of immune system, barrier defense, and microbiome, likely related to genetic causes. No gene has been claimed to contribute to HAEC occurrence, yet. Genetic investigation of HAEC by Whole-Exome Sequencing (WES) on 24 HSCR patients affected (HAEC) or not affected (HSCR-only) by enterocolitis and replication of results on a larger panel of patients allowed the identification of the HAEC susceptibility variant p.H187Q in the Oncostatin-M receptor (OSMR) gene (14.6% in HAEC and 5.1% in HSCR-only, p = 0.0024). Proteomic analysis on the lymphoblastoid cell lines from one HAEC patient homozygote for this variant and one HAEC patient not carrying the variant revealed two well distinct clusters of proteins significantly up or downregulated upon OSM stimulation. A marked enrichment in immune response pathways (q < 0.0001) was shown in the HAEC H187 cell line, while proteins upregulated in the HAEC Q187 lymphoblasts sustained pathways likely involved in pathogen infection and inflammation. In conclusion, OSMR p.H187Q is an HAEC susceptibility variant and perturbates the downstream signaling cascade necessary for the gut immune response and homeostasis maintenance. 相似文献
988.
Yana Tarakanchikova Jamal Alzubi Valentina Pennucci Marie Follo Boris Kochergin Albert Muslimov Ilya Skovorodkin Seppo Vainio Maria N. Antipina Vsevolod Atkin Alexey Popov Igor Meglinski Toni Cathomen Tatjana I. Cornu Dmitry A. Gorin Gleb B. Sukhorukov Irina Nazarenko 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(3)
Efficient delivery of genetic material to primary cells remains challenging. Here, efficient transfer of genetic material is presented using synthetic biodegradable nanocarriers, resembling extracellular vesicles in their biomechanical properties. This is based on two main technological achievements: generation of soft biodegradable polyelectrolyte capsules in nanosize and efficient application of the nanocapsules for co‐transfer of different RNAs to tumor cell lines and primary cells, including hematopoietic progenitor cells and primary T cells. Near to 100% efficiency is reached using only 2.5 × 10?4 pmol of siRNA, and 1 × 10?3 nmol of mRNA per cell, which is several magnitude orders below the amounts reported for any of methods published so far. The data show that biodegradable nanocapsules represent a universal and highly efficient biomimetic platform for the transfer of genetic material with the utmost potential to revolutionize gene transfer technology in vitro and in vivo. 相似文献
989.
Russian Journal of Non-Ferrous Metals - Studies have been conducted to establish the patterns of sulfuric acid dissolution of metal sulfides in the presence of environmentally friendly oxidizing... 相似文献
990.