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1.
Int J Pharm ; 551(1-2): 84-96, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-30194010

ABSTRACT

Ball Milling technique has been used to prepare for the first time Vitis Vinifera extract-silica nanocomposites (VV-SiO2 NCs), which combine the pharmacological effects of the extract with the effectiveness of silica as drug delivery system and active component in the treatment of wound healing. Different contents (1.0, 9.0 and 33.0 wt%) of Vitis Vinifera ethanolic extract were loaded into the silica matrix by grinding the extract with fumed silica using a planetary mill apparatus. The effect of the starting mixture composition and milling time on the final products was examined. The efficiency of the milling process was studied by X-ray Powder Diffraction, Nuclear Magnetic Resonance, and Infrared Spectroscopy, indicating that the natural extract was not affected by the increasing of the milling time. The successful loading of the extract was demonstrated by Nitrogen adsorption/desorption measurements, which showed a decrease in the SSA and pore volume of the silica with the increasing of the extract amount. Morphology of the nanocomposites, investigated by Scanning Electron Microscopy, showed an increased agglomeration in the nanocomposites with the increment of the VV extract amount. Studies on the total phenol quantification and antioxidant activity of the natural extract before and after incorporation in the silica matrix were also carried out. The obtained results indicate that the milling process does not alter the VV extract components, which result to be embedded in the silica matrix. An increase of the antioxidant activity with the increment of the extract amount in the nanocomposites, up to values comparable to the pure VV extract, was also observed.


Subject(s)
Antioxidants/chemistry , Nanocomposites/chemistry , Plant Extracts/chemistry , Silicon Dioxide/chemistry , Vitis , Drug Delivery Systems , Phenols/analysis
3.
Food Funct ; 7(9): 4092-103, 2016 Sep 14.
Article in English | MEDLINE | ID: mdl-27603212

ABSTRACT

We explored the changes in viability and lipid profile occurring in cancer cells, murine melanoma cells (B16F10 cells) and human cervical carcinoma cells (HeLa cells), when exposed to 24 h-treatments with an n-3 PUFA-rich oil obtained by supercritical extraction with CO2 from Mugil cephalus processed roe (bottarga). The composition of the major lipid classes of bottarga oil was determined by the (13)C NMR technique. Reversed-phase HPLC with DAD/ELSD detection was performed to analyze cells' total fatty acid profile and the levels of phospholipids, total/free cholesterol, triacylglycerols, and cholesteryl esters. Cell-based fluorescent measurements of intracellular membranes and lipid droplets were performed on bottarga oil-treated cells using the Nile red staining technique. The treatments of cancer cells with bottarga oil reduced the viability and affected the fatty acid profile, with a significant n-3 PUFA increase in treated cells. Mullet roe oil uptake modulated the cancer cell lipid composition, inducing a remarkable incorporation of health beneficial n-3 PUFA in the polar and neutral lipid fractions. Bottarga oil treatment influenced the synthesis of intracellular membranes and accumulation of cytoplasmic lipid droplets in cancer cells.


Subject(s)
Anticarcinogenic Agents/metabolism , Eggs , Fish Oils/metabolism , Lipid Metabolism , Melanoma/prevention & control , Smegmamorpha , Uterine Cervical Neoplasms/prevention & control , Animals , Anticarcinogenic Agents/analysis , Anticarcinogenic Agents/chemistry , Anticarcinogenic Agents/isolation & purification , Cell Line, Tumor , Cell Survival , Dietary Supplements , Fatty Acids, Omega-3/analysis , Fatty Acids, Omega-3/isolation & purification , Fatty Acids, Omega-3/metabolism , Female , Fish Oils/chemistry , Fish Oils/isolation & purification , Fish Products/analysis , Food, Preserved/analysis , HeLa Cells , Humans , Italy , Lipid Droplets/metabolism , Lipid Droplets/pathology , Melanoma/metabolism , Melanoma/pathology , Mice , Uterine Cervical Neoplasms/metabolism , Uterine Cervical Neoplasms/pathology
4.
J Transl Med ; 14: 273, 2016 09 20.
Article in English | MEDLINE | ID: mdl-27650038

ABSTRACT

The fifth "Melanoma Bridge Meeting" took place in Naples, December 1-5th, 2015. The main topics discussed at this meeting were: Molecular and Immuno advances, Immunotherapies and Combination Therapies, Tumor Microenvironment and Biomarkers and Immunoscore. The natural history of cancer involves interactions between the tumor and the immune system of the host. The immune infiltration at the tumor site may be indicative of host response. Significant correlations were shown between the levels of immune cell infiltration in tumors and patient's clinical outcome. Moreover, incredible progress comes from the discovery of mutation-encoded tumor neoantigens. In fact, as tumors grow, they acquire mutations that are able to influence the response of patients to immune checkpoint inhibitors. It has been demonstrated that sensitivity to PD-1 and CTLA-4 blockade in patients with advanced NSCLC and melanoma was enhanced in tumors enriched for clonal neoantigens. The road ahead is still very long, but the knowledge of the mechanisms of immune escape, the study of tumor neo-antigens as well as of tumor microenvironment and the development of new immunotherapy strategies, will make cancer a more and more treatable disease.


Subject(s)
Immunotherapy , Melanoma/immunology , Humans
5.
Oncogene ; 34(17): 2156-66, 2015 Apr 23.
Article in English | MEDLINE | ID: mdl-25347742

ABSTRACT

The epithelial-mesenchymal transition (EMT) is crucial to cancer progression and metastasis. Although multiple cellular miRNAs have been identified to regulate the EMT and metastasis in cancers, the role of viral miRNAs in cancer progression remains largely unknown. Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV)-associated malignancy typically characterized by its early metastasis. In the present study, we have discovered the involvement of a viral miRNA, EBV-miR-BART7-3p, in the EMT and metastasis of NPC cells. Initially, we observed that EBV-miR-BART7-3p was highly expressed in NPC and positively correlated with lymph node metastasis and clinical stage of NPC. Subsequently, we demonstrated that EBV-miR-BART7-3p enhanced cell migration/invasion in vitro, cancer metastasis in vivo, and particularly the EMT characterized by loss of epithelial markers and gain of mesenchymal features in NPC cells. Furthermore, mechanistic studies disclosed that EBV-miR-BART7-3p targeted a major human tumor suppressor PTEN, modulating PI3K/Akt/GSK-3ß signaling and eventually leading to the high expression and nuclear accumulation of Snail and ß-catenin, which favor EMT. Knockdown of PTEN could phenocopy the effect of EBV-miR-BART7-3p, whereas re-expression of PTEN resulted in a phenotypic reversion. Moreover, these findings were supported by an observation of an EBV-positive cell model in which silencing of endogenous EBV-miR-BART7-3p partially attenuated cell migration/invasion and altered EMT protein expression pattern via reverting PI3K/Akt, Snail and ß-catenin expression. Thus, this study suggests a novel mechanism by which EBV-miR-BART7-3p modulates the EMT and metastasis of NPC cells, and a clinical implication of EBV-miR-BART7-3p as a potential biomarker or therapeutic target.


Subject(s)
Epithelial-Mesenchymal Transition , Epstein-Barr Virus Infections/metabolism , Herpesvirus 4, Human/metabolism , Nasopharyngeal Neoplasms/metabolism , PTEN Phosphohydrolase/biosynthesis , RNA, Neoplasm/metabolism , RNA, Viral/metabolism , Carcinoma , Cell Line , Cell Nucleus/genetics , Cell Nucleus/metabolism , Cell Nucleus/pathology , Epstein-Barr Virus Infections/genetics , Epstein-Barr Virus Infections/pathology , Female , Glycogen Synthase Kinase 3/genetics , Glycogen Synthase Kinase 3/metabolism , Glycogen Synthase Kinase 3 beta , Herpesvirus 4, Human/genetics , Humans , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/genetics , Nasopharyngeal Neoplasms/pathology , Nasopharyngeal Neoplasms/virology , Neoplasm Invasiveness , Neoplasm Metastasis , PTEN Phosphohydrolase/genetics , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , RNA, Neoplasm/genetics , RNA, Viral/genetics , Signal Transduction/genetics
6.
Cell Death Differ ; 21(12): 1936-49, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25215949

ABSTRACT

Emerging evidence suggests that the resistance of cancer stem cells (CSC) to many conventional therapies is one of the major limiting factors of cancer therapy efficacy. Identification of mechanisms responsible for survival and self-renewal of CSC will help design new therapeutic strategies that target and eliminate both differentiated cancer cells and CSC. Here we demonstrated the potential role of proapoptotic protein BAD in the biology of CSC in melanoma, prostate and breast cancers. We enriched CD44(+)/CD24(-) cells (CSC) by tumorosphere formation and purified this population by FACS. Both spheres and CSC exhibited increased potential for proliferation, migration, invasion, sphere formation, anchorage-independent growth, as well as upregulation of several stem cell-associated markers. We showed that the phosphorylation of BAD is essential for the survival of CSC. Conversely, ectopic expression of a phosphorylation-deficient mutant BAD induced apoptosis in CSC. This effect was enhanced by treatment with a BH3-mimetic, ABT-737. Both pharmacological agents that inhibit survival kinases and growth factors that are involved in drug resistance delivered their respective cytotoxic and protective effects by modulating the BAD phosphorylation in CSC. Furthermore, the frequency and self-renewal capacity of CSC was significantly reduced by knocking down the BAD expression. Consistent with our in vitro results, significant phosphorylation of BAD was found in CD44(+) CSC of 83% breast tumor specimens. In addition, we also identified a positive correlation between BAD expression and disease stage in prostate cancer, suggesting a role of BAD in tumor advancement. Our studies unveil the role of BAD in the survival and self-renewal of CSC and propose BAD not only as an attractive target for cancer therapy but also as a marker of tumor progression.


Subject(s)
Apoptosis , Cell Proliferation , Cell Survival , Neoplastic Stem Cells/physiology , bcl-Associated Death Protein/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Cycle , Cell Line, Tumor , Female , Gene Knockdown Techniques , Humans , Male , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Protein Processing, Post-Translational
7.
Br J Cancer ; 110(12): 2955-64, 2014 Jun 10.
Article in English | MEDLINE | ID: mdl-24809778

ABSTRACT

BACKGROUND: Mesenchymal stromal cells (MSCs) are heterogeneous cells with immunoregulatory and wound-healing properties. In cancer, they are known to be an essential part of the tumour microenvironment. However, their role in tumour growth and rejection remains unclear. To investigate this, we co-cultured human MSCs, tumour infiltrating lymphocytes (TIL), and melanoma cells to investigate the role of MSCs in the tumour environment. METHODS: Mesenchymal stromal cells were co-cultured with melanoma antigen-specific TIL that were stimulated either with HLA-A*0201(+) melanoma cells or with a corresponding clone that had lost HLA-A*0201 expression. RESULTS: Activated TIL induced profound pro-inflammatory gene expression signature in MSCs. Analysis of culture supernatant found that MSCs secreted pro-inflammatory cytokines, including TH1 cytokines that have been previously associated with immune-mediated antitumor responses. In addition, immunohistochemical analysis on selected markers revealed that the same activated MSCs secreted both the TH1 cytokine (interleukin-12) and indoleamine 2,3 dioxygenase (IDO), a classical immunosuppressive factor. CONCLUSIONS: This study reflected that the plasticity of MSCs is highly dependent upon microenvironment conditions. Tumour-activated TIL induced TH1 phenotype change in MSCs that is qualitatively similar to the previously described immunologic constant of rejection signature observed during immune-mediated, tissue-specific destruction. This response may be responsible for the in loco amplification of antigen-specific anti-cancer immune response.


Subject(s)
Lymphocytes, Tumor-Infiltrating/immunology , Melanoma/immunology , Mesenchymal Stem Cells/immunology , Skin Neoplasms/immunology , Th1 Cells/immunology , Tumor Microenvironment/immunology , Bone Marrow Cells/immunology , Cell Differentiation/immunology , Cell Line, Tumor , Cell Proliferation , Coculture Techniques , Cytokines/biosynthesis , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , HLA-A2 Antigen/biosynthesis , HLA-A2 Antigen/genetics , Humans , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Interleukin-12 Subunit p35/metabolism
8.
J Chem Phys ; 140(12): 124503, 2014 Mar 28.
Article in English | MEDLINE | ID: mdl-24697455

ABSTRACT

A combined approach of molecular dynamics simulations, wide angle X-ray scattering experiments, and density measurements was employed to study the structural properties of N-methyl-2-pyrrolidone (NMP) + water mixtures over the whole concentration range. Remarkably, a very good agreement between computed and experimental densities and diffraction patterns was achieved, especially if the effect of the mixture composition on NMP charges is taken into account. Analysis of the intermolecular organization, as revealed by the radial and spatial distribution functions of relevant solvent atoms, nicely explained the density maximum observed experimentally.

9.
Br J Cancer ; 109(9): 2412-23, 2013 Oct 29.
Article in English | MEDLINE | ID: mdl-24129241

ABSTRACT

BACKGROUND: Adoptive therapy with tumour-infiltrating lymphocytes (TILs) induces durable complete responses (CR) in ∼20% of patients with metastatic melanoma. The recruitment of T cells through CXCR3/CCR5 chemokine ligands is critical for immune-mediated rejection. We postulated that polymorphisms and/or expression of CXCR3/CCR5 in TILs and the expression of their ligands in tumour influence the migration of TILs to tumours and tumour regression. METHODS: Tumour-infiltrating lymphocytes from 142 metastatic melanoma patients enrolled in adoptive therapy trials were genotyped for CXCR3 rs2280964 and CCR5-Δ32 deletion, which encodes a protein not expressed on the cell surface. Expression of CXCR3/CCR5 in TILs and CXCR3/CCR5 and ligand genes in 113 available parental tumours was also assessed. Tumour-infiltrating lymphocyte data were validated by flow cytometry (N=50). RESULTS: The full gene expression/polymorphism model, which includes CXCR3 and CCR5 expression data, CCR5-Δ32 polymorphism data and their interaction, was significantly associated with both CR and overall response (OR; P=0.0009, and P=0.007, respectively). More in detail, the predicted underexpression of both CXCR3 and CCR5 according to gene expression and polymorphism data (protein prediction model, PPM) was associated with response to therapy (odds ratio=6.16 and 2.32, for CR and OR, respectively). Flow cytometric analysis confirmed the PPM. Coordinate upregulation of CXCL9, CXCL10, CXCL11, and CCL5 in pretreatment tumour biopsies was associated with OR. CONCLUSION: Coordinate overexpression of CXCL9, CXCL10, CXCL11, and CCL5 in pretreatment tumours was associated with responsiveness to treatment. Conversely, CCR5-Δ32 polymorphism and CXCR3/CCR5 underexpression influence downregulation of the corresponding receptors in TILs and were associated with likelihood and degree of response.


Subject(s)
Interleukin-2/therapeutic use , Melanoma/drug therapy , Melanoma/metabolism , Receptors, CCR5/metabolism , Receptors, CXCR3/metabolism , Adolescent , Adult , Aged , Biopsy , Cell Movement/drug effects , Cell Movement/genetics , Female , Gene Expression , Genotype , Humans , Ligands , Lymphocytes, Tumor-Infiltrating/drug effects , Lymphocytes, Tumor-Infiltrating/pathology , Male , Melanoma/genetics , Melanoma/pathology , Middle Aged , Polymorphism, Genetic , Receptors, CCR5/genetics , Receptors, CXCR3/genetics , Signal Transduction , Up-Regulation , Young Adult
10.
Br J Cancer ; 109(1): 76-82, 2013 Jul 09.
Article in English | MEDLINE | ID: mdl-23807161

ABSTRACT

BACKGROUND: Several lines of evidence suggest a dichotomy between immune active and quiescent cancers, with the former associated with a good prognostic phenotype and better responsiveness to immunotherapy. Central to such dichotomy is the master regulator of the acute inflammatory process interferon regulatory factor (IRF)-1. However, it remains unknown whether the responsiveness of IRF-1 to cytokines is able to differentiate cancer immune phenotypes. METHODS: IRF-1 activation was measured in 15 melanoma cell lines at basal level and after treatment with IFN-γ, TNF-α and a combination of both. Microarray analysis was used to compare transcriptional patterns between cell lines characterised by high or low IRF-1 activation. RESULTS: We observed a strong positive correlation between IRF-1 activation at basal level and after IFN-γ and TNF-α treatment. Microarray demonstrated that three cell lines with low and three with high IRF-1 inducible translocation scores differed in the expression of 597 transcripts. Functional interpretation analysis showed mTOR and Wnt/ß-cathenin as the top downregulated pathways in the cell lines with low inducible IRF-1 activation, suggesting that a low IRF-1 inducibility recapitulates a cancer phenotype already described in literature characterised by poor prognosis. CONCLUSION: Our findings support the central role of IRF-1 in influencing different tumour phenotypes.


Subject(s)
Interferon Regulatory Factor-1/metabolism , Interferon-gamma/pharmacology , Melanoma/immunology , Cell Line, Tumor , Enzyme Activation , Humans , Immunotherapy , Interferon-gamma/metabolism , Melanoma/therapy , NF-kappa B/metabolism , TOR Serine-Threonine Kinases/metabolism , Transcription, Genetic , Tumor Necrosis Factor-alpha/pharmacology , Wnt Proteins/metabolism , beta Catenin/metabolism
11.
Cell Death Dis ; 4: e634, 2013 May 16.
Article in English | MEDLINE | ID: mdl-23681229

ABSTRACT

Connective tissue growth factor (CTGF) has different roles in different types of cancer. However, the involvement and molecular basis of CTGF in tumor progression and prognosis of human nasopharyngeal carcinoma (NPC) have almost never been reported. In this study, we observed that downregulated CTGF expression was significantly associated with NPC progression and poor prognosis. Knockdown of CTGF markedly elevated the ability of cell proliferation in vivo and in vitro. Subsequently, we discovered that the reduction of CTGF increased the expression of miR-18b, an oncomir-promoting cell proliferation. Further, we discovered that attenuated CTGF-mediated upregulation of miR-18b was dependent on the increased binding of transcription factors Jun proto-oncogene (C-Jun) and v-Myc myelocytomatosis viral oncogene homolog (C-Myc) to miR-18b promoter region via phosphoinositide 3-kinase (PI3K)/AKT pathway. Finally, we further found that miR-18b directly suppressed the expression of CTGF in NPC. In clinical fresh specimens, miR-18b was widely overexpressed and inversely correlated with CTGF expression in NPC. Our studies are the first to demonstrate that reduced CTGF as an unfavorable prognosis factor mediates the activation of miR-18b, an oncomir directly suppresses CTGF expression, by PI3K/AKT/C-Jun and C-Myc and promotes cell growth of NPC.


Subject(s)
MicroRNAs/metabolism , Nasopharyngeal Neoplasms/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Animals , Carcinoma , Cell Line, Tumor , Cell Proliferation , Cell Transformation, Neoplastic , Connective Tissue Growth Factor/antagonists & inhibitors , Connective Tissue Growth Factor/genetics , Connective Tissue Growth Factor/metabolism , Down-Regulation , Female , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Middle Aged , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/pathology , Phosphatidylinositol 3-Kinases/genetics , Prognosis , Promoter Regions, Genetic , Proto-Oncogene Mas , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-jun/metabolism , Proto-Oncogene Proteins c-myc/metabolism , RNA Interference , RNA, Small Interfering/metabolism , Transplantation, Heterologous
12.
Br J Cancer ; 105(2): 320-6, 2011 Jul 12.
Article in English | MEDLINE | ID: mdl-21654679

ABSTRACT

BACKGROUND: We conducted the first analysis of viral microRNAs (miRNAs) in lung cancer, with a focus on Epstein-Barr virus (EBV). METHODS: We evaluated viral miRs with a two-channel oligo-array targeting mature, anti-sense miRNAs in 290 cases. In 48 cases, we compared microarray and real-time quantitative PCR (qPCR) expression for three EBV miRNAs. We tested for EBV DNA, RNA, and protein in tumour tissue from six cases with and six cases without strong qPCR-based evidence of EBV miRNAs. RESULTS: The EBV miRNAs strongly differentiated between adenocarcinoma and squamous cell carcinoma using the microarray (P<0.01 for 9 out of 16 EBV miRNAs). However, microarray and qPCR measurements of BART1, BART2, and BHRF1-3 expression were not significantly correlated (P=0.53, 0.94, and 0.47, respectively). Although qPCR provided substantial evidence of EBV miRNAs in 7 out of 48 cases, only 1 of these 7 cases had detectable EBV DNA in tumour tissue. None had detectable EBV RNA or protein by histochemical stains. CONCLUSION: In a comprehensive evaluation of EBV miRNA, DNA, RNA, and protein in lung cancer, we found little evidence of EBV in lung tumour tissue. Discrepancies between microarray- and qPCR-based strategies highlight the difficulty of validating molecular markers of disease. Our results do not support a role of EBV in lung cancer.


Subject(s)
Adenocarcinoma/virology , Carcinoma, Squamous Cell/virology , Herpesvirus 4, Human/genetics , Lung Neoplasms/virology , MicroRNAs/genetics , Adenocarcinoma/complications , Adenocarcinoma/genetics , Adult , Aged , Aged, 80 and over , Algorithms , Carcinoma, Squamous Cell/complications , Carcinoma, Squamous Cell/genetics , Case-Control Studies , DNA, Viral/analysis , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/genetics , Epstein-Barr Virus Infections/virology , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Gene Expression Regulation, Viral , Herpesvirus 4, Human/isolation & purification , Herpesvirus 4, Human/physiology , Humans , Lung Neoplasms/complications , Lung Neoplasms/genetics , Male , MicroRNAs/analysis , MicroRNAs/physiology , Microarray Analysis , Middle Aged , RNA, Viral/analysis , Viral Proteins/analysis
13.
Br J Cancer ; 103(12): 1870-4, 2010 Dec 07.
Article in English | MEDLINE | ID: mdl-21102586

ABSTRACT

BACKGROUND: MicroRNAs (miRs) have an important role in lung carcinogenesis and progression. Single-nucleotide polymorphisms (SNPs) in genes involved in miR biogenesis may affect miR expression in lung tissue and be associated with lung carcinogenesis and progression. METHODS: we analysed 12 SNPs in POLR2A, RNASEN and DICER1 genes in 1984 cases and 2073 controls from the Environment And Genetics in Lung cancer Etiology (EAGLE) study. We investigated miR expression profiles in 165 lung adenocarcinoma (AD) and 125 squamous cell carcinoma tissue samples from the same population. We used logistic and Cox regression models to examine the association of individual genotypes and haplotypes with lung cancer risk and with lung cancer-specific survival, respectively. SNPs-miR expression associations in cases were assessed using two-sample t-tests and global permutation tests. RESULTS: a haplotype in RNASEN (Drosha) was significantly associated with shorter lung cancer survival (hazard ratio=1.86, 95% CI=1.19-2.92, P=0.007). In AD cases, a SNP within the same haplotype was associated with reduced RNASEN mRNA expression (P=0.013) and with miR expression changes (global P=0.007) of miRs known to be associated with cancer (e.g., let-7 family, miR-21, miR-25, miR-126 and miR15a). CONCLUSION: inherited variation in the miR-processing machinery can affect miR expression levels and lung cancer-specific survival.


Subject(s)
Lung Neoplasms/genetics , MicroRNAs/analysis , Polymorphism, Single Nucleotide , RNA Interference , DEAD-box RNA Helicases/genetics , Haplotypes , Humans , Lung Neoplasms/mortality , Ribonuclease III/genetics
14.
J Med Eng Technol ; 34(1): 7-22, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19995147

ABSTRACT

Polymeric heart valves could offer an optimum alternative to current prostheses, by joining the advantages of mechanical and bioprosthetic valves. Though a number of materials suitable for this application have recently become available, significant improvements in the valve design are still needed. In this paper, a novel polymeric heart valve design is proposed and its optimization procedure, based on the use of finite elements, is described. The design strategy was aimed at reducing the energy absorbed during the operating cycle, resulting in high hydrodynamic performances and reduced stress levels. The efficacy of the design strategy was assessed by comparing the valve dynamics and stress levels predicted numerically during the cycle with those of an existing and well qualified polymeric valve design. The improved hydrodynamic performance of the proposed design was confirmed experimentally, by in vitro testing in a pulse duplicator.


Subject(s)
Biocompatible Materials , Heart Valve Prosthesis , Models, Cardiovascular , Polymers/therapeutic use , Computer Simulation , Equipment Design , Finite Element Analysis , Materials Testing
15.
J Phys Condens Matter ; 21(37): 375106, 2009 Sep 16.
Article in English | MEDLINE | ID: mdl-21832337

ABSTRACT

A complete structural study has been carried out on sodium borophosphate glass containing increasing amounts of either niobium or tantalum. A combination of high energy x-ray diffraction, neutron diffraction, extended x-ray absorption fine structure, nuclear magnetic resonance, and infrared and Raman spectroscopy has been used to discern the local atomic structure of each component and the changes with M content, where M is either niobium or tantalum. The glasses are found to consist of tetrahedral borate and phosphate with octahedral MO(6). As expected, B and P play the roles of tetrahedral network formers. At low M content there are isolated MO(6) units with [Formula: see text] and [Formula: see text] linkages that contribute to the glass network. As the M content increases, the number of [Formula: see text] links increases, and at the highest M content each MO(6) unit is connected to several others. The octahedra become significantly distorted as the niobium content increases, an effect that is not seen for tantalum.

16.
Chem Phys Lipids ; 151(2): 69-76, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17996196

ABSTRACT

13C NMR spectroscopy, in conjunction with HPLC and GC techniques, has been used to study the molecular composition of lipids extracted from commercial products of bottarga. To this goal, both the saponifiable and unsaponifiable fractions of lipid extracts were also examined by 13C NMR. Among the major lipid classes wax esters (WE) showed a concentration of more than 50mol%, triacylglycerols (TAG) and phospholipids (PL) represented a minor fraction. Concentrations up to 29mol% of free fatty acids (FFA) were found. The most represented fatty alcohol was 16:0 that accounted for more than 50%, among fatty acids the most represented were 16:1 n-7, 22:6 n-3, 18:1 n-9, 16:0, and 20:5 n-3, in particular the n-3 polyunsaturated fatty acids (PUFA) averaged 40mg/g of the edible portion. 13C NMR spectroscopy put in evidence that cholesterol was present in its free and esterified forms and its total content was measured as ca. 10mg/g of the edible portion.


Subject(s)
Lipids/chemistry , Ovum/chemistry , Smegmamorpha , Sodium Chloride/chemistry , Alkenes/chemistry , Animals , Chromatography, Gas , Chromatography, High Pressure Liquid , Female , Magnetic Resonance Spectroscopy , Nitrogen/chemistry , Oxygen/chemistry
18.
Lipids ; 41(11): 1039-48, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17263303

ABSTRACT

Intact portions of melon, the echolocation organ of the striped dolphin (Stenella coeruleoalba), and the corresponding raw oils were analyzed by means of one- and two dimensional 1H and 13C NMR techniques. For comparative purposes the tissue and the raw oil of head blubber were also examined. Complete assignments of the spectra were obtained. Furthermore, dynamics of the lipid components was investigated by means of 13C NMR spin lattice relaxation time (T1). Analysis of the data revealed that lipid molecules in the tissue compartments experience a liquid-like microenvironment and that T1 values depend on the lipid composition and/or organization in the intact tissue framework. In particular, a dependence of the T1 values on the wax esters content in melon intact tissues was found. A possible correlation between dynamic parameters and sound propagation properties has been hypothesized.


Subject(s)
Adipose Tissue/chemistry , Magnetic Resonance Spectroscopy , Oils/chemistry , Stenella/metabolism , Adipose Tissue/metabolism , Animals , Carbon Isotopes , Echolocation/physiology , Hydrogen , Oils/metabolism
20.
Genes Immun ; 5(8): 621-30, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15573087

ABSTRACT

The molecular mechanisms underlying the increase of natural killer (NK) cell anticancer activity mediated by interleukin (IL)-10 have not been elucidated. The aim of this study was to identify potential molecular mediators of IL-10 stimulatory effects by exploring the NK cell gene display induced by this cytokine. Gene profile was determined by high-throughput cDNA microarray and quantitative real-time PCR. In vitro, NK cells resting or conditioned with IL-10 were tested for cytotoxicity, migration and proliferation. IL-10 enhanced mRNA levels of cell activation/cytotoxicity-related genes (eg secretogranin, TIA-1, HMG-1, interferon-inducible genes) not upregulated by IL-2. In line with these findings, IL-10 increased NK cell in vitro cytotoxicity against Daudi cells. Unlike IL-2, IL-10 did not show any significant effect on NK cell in vitro proliferation and migration. However, gene profile analysis showed that IL-10 increased the expression of cell migration-related genes (eg L-selectin, vascular endothelium growth factor receptor-1, plasminogen activator, tissue; formyl peptide receptor, lipoxin A4 receptor), which might support a stimulatory effect not evident with the in vitro functional assay. Overall, gene profiling allowed us to formulate new hypotheses regarding the molecular pathways underlying the stimulatory effects of IL-10 on NK cells, supporting further investigation aimed at defining its role in cancer immune rejection.


Subject(s)
Gene Expression Profiling , Gene Expression Regulation/drug effects , Interleukin-10/pharmacology , Killer Cells, Natural/metabolism , Neoplasms/prevention & control , Cell Movement/drug effects , Cell Proliferation/drug effects , Cytotoxicity Tests, Immunologic , DNA Primers , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Humans , Interleukin-10/metabolism , Killer Cells, Natural/drug effects , Neoplasms/immunology , Oligonucleotide Array Sequence Analysis , Poly(A)-Binding Proteins , Proteins/metabolism , RNA-Binding Proteins , Reverse Transcriptase Polymerase Chain Reaction , T-Cell Intracellular Antigen-1
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