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1.
J Control Release ; 330: 1095-1105, 2021 02 10.
Article in English | MEDLINE | ID: mdl-33188827

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant disease, where even surgical resection and aggressive chemotherapy produce dismal outcomes. Immunotherapy is a promising alternative to conventional treatments, possessing the ability to elicit T cell-mediated killing of tumor cells and prevent disease recurrence. Immunotherapeutic approaches thus far have seen limited success in PDAC due to a poorly immunogenic and exceedingly immunosuppressive tumor microenvironment, which is enriched with dysfunctional and immunosuppressed antigen-presenting cells (APCs). We developed a highly potent immunostimulatory nanoparticle (immuno-NP) to activate and expand APCs in the tumor and induce local secretion of interferon ß (IFNß), which is a pro-inflammatory cytokine that plays a major role in APC recruitment. The effectiveness of the immuno-NP stems from its dual cargo of two synergistic immune modulators consisting of an agonist of the stimulator of interferon genes (STING) pathway and an agonist of the Toll-like receptor 4 (TLR4) pathway. We show the functional synergy of the dual-agonist cargo can be tweaked by adjusting the ratio of the two agonists loaded in the immuno-NP, leading to an increase in IFNß production (11-fold) compared to any single agonist immuno-NP variant. Using the orthotopic murine Panc02 model of PDAC, we show that systemic administration allowed immuno-NPs to deposit into the perivascular regions of the tumor, which coincided with the APC-rich tumor areas leading to predominant uptake of immuno-NPs by APCs. The immuno-NPs were effectively taken up by a significant portion of dendritic cells in the tumor (>56%). This led to a significant expansion of APCs, resulting in an 11.5-fold increase of dendritic cells and infiltration of lymphocytes throughout the pancreatic tumor compared to untreated animals.


Subject(s)
Nanoparticles , Pancreatic Neoplasms , Animals , Antigen-Presenting Cells , Immunization , Immunotherapy , Mice , Pancreatic Neoplasms/drug therapy , Tumor Microenvironment
2.
Sci Rep ; 9(1): 3718, 2019 03 06.
Article in English | MEDLINE | ID: mdl-30842491

ABSTRACT

The biogeochemistry of hypersaline environments is strongly influenced by changes in biological processes and physicochemical parameters. Although massive evaporation events have occurred repeatedly throughout Earth history, their biogeochemical cycles and global impact remain poorly understood. Here, we provide the first nitrogen isotopic data for nutrients and chloropigments from modern shallow hypersaline environments (solar salterns, Trapani, Italy) and apply the obtained insights to δ15N signatures of the Messinian salinity crisis (MSC) in the late Miocene. Concentrations and δ15N of chlorophyll a, bacteriochlorophyll a, nitrate, and ammonium in benthic microbial mats indicate that inhibition of nitrification suppresses denitrification and anammox, resulting in efficient ammonium recycling within the mats and high primary productivity. We also suggest that the release of 15N-depleted NH3(gas) with increasing salinity enriches ammonium 15N in surface brine (≈34.0‰). Such elevated δ15N is also recorded in geoporphyrins isolated from sediments of the MSC peak (≈20‰), reflecting ammonium supply sufficient for sustaining phototrophic primary production. We propose that efficient nutrient supply combined with frequent bottom-water anoxia and capping of organic-rich sediments by evaporites of the Mediterranean MSC could have contributed to atmospheric CO2 reduction during the late Miocene.

3.
Fish Shellfish Immunol ; 63: 277-284, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28232283

ABSTRACT

The present study was conducted to determine the potential effect of the dietary intake of fenugreek (Trigonella foenum graecum) seeds alone or in combination with Bacillus licheniformis, Lactobacillus plantarum or B. subtilis on gilthead seabream quality and antioxidant response after 2 and 3 weeks of experimental feeding. The results showed that the supplements did not affect the percentage of the fatty acid profiles of muscle, demonstrating that all the additives tested can be administrated without any negative effect on biochemical composition and quality of gilthead seabream. The quantification of thiobarbituric acid reactive substances in muscle demonstrated the significant beneficial effect of the experimental diets compared with the control one. Besides, an increase in superoxide dismutase and catalase in liver was recorded after 3 weeks of administration of experimental diets. Furthermore, real time qPCR revealed that dietary supplementation with FEBS significantly enhances the expression of scavenging enzymes, such as cat and gr genes in the liver after 3 weeks. The findings suggest that the administration of fenugreek supplement alone or combined with probiotic strains could be considered as a good source of natural antioxidants and as a functional aquafeed ingredient for gilthead seabream.


Subject(s)
Dietary Supplements , Immunity, Innate , Plant Extracts/metabolism , Probiotics , Sea Bream/immunology , Trigonella/metabolism , Adjuvants, Immunologic/administration & dosage , Animal Feed/analysis , Animals , Bacillus licheniformis/chemistry , Bacillus subtilis/chemistry , Diet/veterinary , Lactobacillus plantarum/chemistry , Plant Extracts/administration & dosage , Random Allocation , Sea Bream/metabolism
4.
Fish Shellfish Immunol ; 60: 50-58, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27856325

ABSTRACT

The use of immunostimulants is considered a promising preventive practice that may help to maintain animal welfare and a healthy environment, while increasing production and providing higher profits. The purpose of this study was to evaluate the effects on gilthead seabream (Sparus aurata L.) of the dietary administration of fenugreek (Trigonella foenum graecum) seeds, alone or combined with one of the following probiotic strains: Bacillus licheniformis (TSB27), Lactobacillus plantarum or Bacillus subtilis (B46). Gilthead seabream were fed a control or one of the supplemented diets for 3 weeks. The effects of these supplemented diets on growth performance parameters and the humoral immune response (natural haemolytic complement, peroxidase, total IgM levels, proteases and antiproteases activities) were evaluated after 2 and 3 weeks of feeding. Simultaneously, the expression levels of some immune-relevant genes (igm, tcr-ß, csfr1 and bd) were measured in the head-kidney. Interestingly, all probiotic supplemented diets increased seabream growth rates, especially the B. licheniformis supplemented diet. Generally, humoral immune parameters were enhanced by the dietary supplementation at the different time points measured. The results showed a significant increases in the immune parameters, principally in fish fed only fenugreek or fenugreek combined with B. subtilis. Furthermore, real time qPCR revealed that dietary supplementation significantly enhances the expression of immune-associated genes in the head-kidney, particularly igm gene expression. These results suggest that fenugreek alone or combined with one of the probiotic strains mentioned enhances the immune response of gilthead seabream, a species with one of the highest rates of production in marine aquaculture.


Subject(s)
Diet/veterinary , Dietary Supplements , Plant Extracts/immunology , Probiotics , Sea Bream/physiology , Trigonella/immunology , Animal Feed/analysis , Animals , Fish Proteins/genetics , Fish Proteins/metabolism , Gram-Negative Bacteria/immunology , Plant Extracts/administration & dosage , Real-Time Polymerase Chain Reaction/veterinary , Sea Bream/genetics , Sea Bream/growth & development , Sea Bream/immunology , Trigonella/chemistry
5.
Nat Prod Res ; 31(6): 626-631, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27686856

ABSTRACT

Consumption of tomato and tomato products is positively related to the reduction in cardiovascular disease and several types of cancer, thanks to the presence of natural compounds, such as antioxidants. Peels and seeds fractions of tomato, collected after industrial processing in Tunisian industries, were analysed for nutritional and antioxidants composition in perspective of its utilisation. Proximate composition, fatty acids profile, carotenoids, such as lycopene and beta-carotene, polyphenols contents, demonstrated the good potential of these residual products as a source of natural compounds, useful for food and nutraceuticals applications.


Subject(s)
Biological Products/chemistry , Solanum lycopersicum/chemistry , Antioxidants/analysis , Biphenyl Compounds/chemistry , Carotenoids/analysis , Carotenoids/pharmacology , Fatty Acids/analysis , Food Handling , Food Industry , Free Radical Scavengers/chemistry , Free Radical Scavengers/pharmacology , Fruit/chemistry , Lycopene , Picrates/chemistry , Polyphenols/analysis , Polyphenols/pharmacology , Seeds/chemistry , Tunisia
6.
Theriogenology ; 88: 145-151, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-27751603

ABSTRACT

The effect of rearing temperature on gonad differentiation and growth was evaluated in sea bass (Dicentrarchus labrax). One control group (CG, n = 60) and two experimental groups (EG1, n = 30; EG2, n = 30) were selected. CG was reared at 15.0 °C during 10 days post-hatch (dph) and at 19.0 °C throughout the remaining larval and post-larval development. EG1 was exposed to 14.5 °C from 1 to 50 dph, followed by an increase to 20 °C until sampling (176 dph). EG2 was exposed to 14.5 °C from 1 to 37 dph, followed by an increase to 20 °C until sampling (226 dph); 30 fish from CG were randomly sampled at 176 dph (CG1, control for EG1) and 30 fish were sampled at 226 dph (CG2, control for EG2). Weight, total and fork length measurement, and gonad collection were performed. All biometric indices were higher in EG1 and EG2 than in CG1 and CG2, respectively. Histologic analysis reported 100% of undifferentiated gonads in CG1 and; EG1 reported 80% of undifferentiated gonads and 20% of gonads at early differentiation toward the male line. CG2 reported 34% of undifferentiated gonads, 10% of gonads at early differentiation toward the female line, 23% of gonads at early differentiation toward the male line, and 33% of gonads with intratesticular oocytes. EG2 reported 47% of gonads differentiated in testis, 33% gonads differentiated in ovary, and 20% of gonads with intratesticular oocytes. These results suggest that water temperature plays an important role in the process of gonad differentiation and growth of sea bass.


Subject(s)
Bass/growth & development , Ovary/growth & development , Sexual Maturation/physiology , Temperature , Testis/growth & development , Water , Animals , Female , Larva/growth & development , Male
7.
Mol Pharmacol ; 77(5): 854-63, 2010 May.
Article in English | MEDLINE | ID: mdl-20159939

ABSTRACT

In this article, we demonstrate that the synthetic cannabinoid R-(+)-(2,3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrol[1,2,3-de]-1,4-benzoxazin-6-yl)-(1-naphthalenyl) methanone mesylate (WIN 55,212-2) sensitizes human hepatocellular carcinoma (HCC) cells to apoptosis mediated by tumor necrosis-related apoptosis inducing ligand (TRAIL). The apoptotic mechanism induced by treatment with WIN/TRAIL combination involved the loss of the mitochondrial transmembrane potential and led to the activation of caspases. In HCC cells, WIN treatment induced the up-regulation of TRAIL death receptor DR5, an effect that seemed to be related to the increase in the level of p8 and CHOP, two factors implicated in cellular stress response and apoptosis. This relationship was suggested by the observation that the down-regulation of p8 or CHOP by specific small interfering RNAs attenuated both WIN-mediated DR5 up-regulation and the cytotoxicity induced by WIN/TRAIL cotreatment. Moreover, WIN induced a significant decrease in the levels of some survival factors (survivin, c-inhibitor of apoptosis protein 2, and Bcl-2) and in particular in that of the active phosphorylated form of AKT. This event seemed to be dependent on the transcription factor peroxisome proliferator-activated receptor-gamma whose level significantly increased after WIN treatment. Therefore, both the induction of DR5 via p8 and CHOP and the down-regulation of survival factors seem to be crucial for the marked synergistic effects induced by the two drugs in HCC cells. Taken together, the results reported in this article indicate that WIN/TRAIL combination could represent a novel important tool for the treatment of HCC.


Subject(s)
Apoptosis/physiology , Benzoxazines/pharmacology , Cannabinoids/pharmacology , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/metabolism , Morpholines/pharmacology , Naphthalenes/pharmacology , Receptors, TNF-Related Apoptosis-Inducing Ligand/physiology , TNF-Related Apoptosis-Inducing Ligand/pharmacology , Transcription Factor CHOP/physiology , Apoptosis/drug effects , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor/drug effects , Cell Line, Tumor/physiology , DNA Primers , DNA, Complementary/drug effects , DNA, Complementary/genetics , DNA, Neoplasm/drug effects , DNA, Neoplasm/genetics , Flow Cytometry , Gene Amplification , Humans , Membrane Potentials/drug effects , Membrane Potentials/physiology , Mitochondrial Membranes/drug effects , Mitochondrial Membranes/physiology , Receptors, TNF-Related Apoptosis-Inducing Ligand/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factor CHOP/drug effects
8.
FEBS Lett ; 579(3): 615-20, 2005 Jan 31.
Article in English | MEDLINE | ID: mdl-15670817

ABSTRACT

This study describes the molecular mechanism by which treatment with 3-AB, a potent inhibitor of PARP, allows human osteosarcoma MG-63 cells to restrict growth and enter differentiation. Our findings show that in MG-63 cells, aberrant gene expression keeps Rb protein constitutively inactivated through hyperphosphorylation and this promotes uncontrolled proliferation of the cells. After 3-AB-treatment, the poly(ADP-ribosyl)ation of nuclear proteins markedly decreases and this results in an increase in both the hypophosphorylated active form of Rb and pRb/E2F complexes. These effects are accompanied by G1 arrest, downregulation of gene products required for proliferation (cyclin D1, beta-catenin, c-Jun, c-Myc and Id2) and upregulation of those implicated in the osteoblastic differentiation (p21/Waf1, osteopontin, osteocalcin, type I collagen, N-cadherins and alkaline phosphatase). Our study suggests that use of PARP inhibitors may induce a remodeling of chromatin with the reprogramming of gene expression and the activation of differentiation.


Subject(s)
Benzamides/pharmacology , Cell Differentiation/drug effects , Enzyme Inhibitors/pharmacology , Osteosarcoma/pathology , Poly(ADP-ribose) Polymerase Inhibitors , Adenosine Diphosphate Ribose/metabolism , Base Sequence , Blotting, Western , Cell Cycle Proteins/metabolism , Cell Line, Tumor , DNA Primers , DNA-Binding Proteins/metabolism , E2F Transcription Factors , Flow Cytometry , G1 Phase/drug effects , Gene Expression Regulation , Humans , Immunoprecipitation , Osteosarcoma/enzymology , Phosphorylation , Retinoblastoma Protein/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/metabolism
9.
Comp Biochem Physiol B ; 99(2): 251-5, 1991.
Article in English | MEDLINE | ID: mdl-1764905

ABSTRACT

1. Diet, time from last feeding, temperature, season and sexual stage are some of the factors influencing the lipoprotein pattern. 2. Keeping these factors constant species-specific differences observed among lipoprotein patterns of Sparus aurata, Puntazzo puntazzo, Diplodus sargus, Diplodus vulgaris and Dicentrarchus labrax are discussed. 3. Feeding habits and therefore lipid absorption and the rate of lipoprotein maturation process are the factors determining the observed differences.


Subject(s)
Fishes/blood , Lipoproteins/blood , Animals , Cholesterol/blood , Electrophoresis, Agar Gel , Lipids/blood , Lipoproteins/isolation & purification , Phospholipids/blood , Species Specificity , Triglycerides/blood
10.
J Submicrosc Cytol ; 18(2): 449-52, 1986 Apr.
Article in English | MEDLINE | ID: mdl-3712515

ABSTRACT

Data are presented relating conventional transmission electron microscope (CTEM) ultrastructural observations of the monomeric phenotypic variant (Hp 1-1) of the haptoglobin class of blood glycoproteins. Through comparison of these findings with homologous published data, obtained by means of scanning transmission electron microscopy (STEM), the validity of CTEM in molecule shape and fine structure determination is confirmed. An experimental procedure for Hp 1-1 crystallization is also reported.


Subject(s)
Haptoglobins , Hemoglobins , Crystallization , Haptoglobins/analysis , Hemoglobins/analysis , Humans , Macromolecular Substances , Microscopy, Electron , Phenotype , Protein Conformation
11.
J Submicrosc Cytol ; 16(4): 787-94, 1984 Oct.
Article in English | MEDLINE | ID: mdl-6389899

ABSTRACT

New preparative methods have been devised which allow electron microscope observation of T-even head substructure, under conditions of negative staining. Capsomeric constitution of the head shell could so be confirmed and demonstrated for T2 and T4. In addition capsomere size and shell thickness of the head of both phages have been determined and the structural organization of the DNA inside T4 head revealed.


Subject(s)
T-Phages/ultrastructure , DNA, Viral/analysis , Histological Techniques , Indicators and Reagents , Microscopy, Electron/methods , Solvents
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