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1.
Sci Total Environ ; 930: 172836, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38685435

ABSTRACT

To achieve carbon neutrality by 2050, many companies have started implementing sustainability policies. The aim of this work, as result of collaboration between Universities and companies, is to assess the environmental impacts associated with the production of alternative formulations of porcelain stoneware. The proposed formulations contain extraction scraps and chamotte and have promising technological properties. A comparative analysis of the life cycle in three different scenarios was carried out to assess the environmental footprint of the final products. The analyzed scenarios were a glazed porcelain stoneware (which was taken as a reference and is commercially available), a porcelain stoneware containing pumice scraps, and one containing volcanic lapillus scraps. It was observed that the transportation of raw materials has the largest environmental impact, followed by the production and extraction of the raw materials themselves. From the performed analysis, it was possible to observe that by replacing the currently used materials by the ones hereby studied, environmental benefits can be obtained. In particular, depending on the considered pollutant, the environmental impact can be reduced between a minimum of about 8 % (Freshwater Aquatic Ecotoxicity category) to a maximum of 48 % (Acidification category). In a time when raw materials supply is difficult, the use of scraps, which would otherwise be disposed of, is particularly interesting and can lead to the production of an environmentally friendly product.

2.
Nanoscale ; 10(2): 657-665, 2018 Jan 03.
Article in English | MEDLINE | ID: mdl-29239447

ABSTRACT

The immobilization of proteins on carbon nanotubes (CNTs) has been widely reported mainly for the preparation of sensors while the conjugation of enzymes for therapeutic purposes has scarcely been considered. Herein we report, to the best of our knowledge, the first example of intracellular delivery of a therapeutic enzyme by means of CNTs, retaining its activity. Mucopolysaccharidosis I is a rare genetic disease characterized by the deficiency or absence of the activity of the α-l-iduronidase (IDUA) enzyme. We evaluated the capacity of the recombinant form of the human IDUA enzyme, laronidase (Aldurazyme®), conjugated with CNTs to be internalized by fibroblasts from subjects affected with Mucopolysaccharidosis type I and the capacity of the enzyme to retain its activity after internalization. The enzyme was successfully delivered into the lysosomal space and the enzymatic activity of the conjugate was preserved after internalization up to 48 hours. This paves the way towards the use of such a kind of construct for therapeutic applications.


Subject(s)
Drug Carriers , Iduronidase/administration & dosage , Mucopolysaccharidosis I/drug therapy , Nanotubes, Carbon , Cells, Cultured , Fibroblasts/drug effects , Humans , Recombinant Proteins/administration & dosage , Skin/cytology
3.
Waste Manag Res ; 35(10): 1055-1063, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28823227

ABSTRACT

The main objective of this work was to study the sintering process and technological properties of new fired bricks based on high amount of post-treated municipal solid waste incinerator bottom ash and refractory clay. In addition, the effect of the minor addition of flux (Na2CO3) or reinforce (corundum) was also highlighted. Several methods were used to study the effect of compositions variations on the sintering process, structure and the mechanical characteristics of the test briquettes. Differential thermal analysis (TG/DTA) and dilatometry techniques were applied to study the thermal behaviour while scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy and high-temperature X-ray diffraction were used to elucidate the structure and the phase composition. The mechanical characteristics were estimated by micro-indentation, strength and various physical tests (porosity, linear shrinkage and water absorption, etc). The results highlight the possibility to use very high amount of municipal solid waste incinerator bottom ashes in the production of new fired bricks with good performances at all levels. It is also shown that the addition of additives managed the final properties, affecting the crystal phase formation, porosity and greatly the strength of the samples.


Subject(s)
Incineration , Solid Waste , Aluminum Oxide , X-Ray Diffraction
4.
J Ethnopharmacol ; 175: 412-21, 2015 Dec 04.
Article in English | MEDLINE | ID: mdl-26403594

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Drypetes klainei Pierre ex Pax is used in Cameroon by Baka Pygmies in the wound healing process and for the treatment of burns. AIM OF THE STUDY: To validate the traditional use of D. klainei Pierre ex Pax stem bark extracts through the evaluation of their antimicrobial properties and their ability to improve wound healing process in fibroblast cell cultures. MATERIALS AND METHODS: The antimicrobial properties of D. klainei extracts were evaluated against Staphylococcus aureus ATCC 6538, Streptococcus pyogenes ATCC 19615, Escherichia coli ATCC 10536, Candida albicans ATCC 10231, on the basis of the minimum inhibitory concentration (MIC) and the minimum bactericidal-fungicidal concentration (MBC-MFC) by the macrodilution method. The extracts abilities to accelerate wound healing were studied on murine and human fibroblasts in terms of cell viability and migration (scratch wound-healing assay). RESULTS: All the extracts were non-toxic against the selected microorganisms at the tested concentrations, and significantly improve wound healing process in vitro, compared to untreated controls. However, the defatted methanol extract was active at lower concentrations, compared to the water extract. CONCLUSIONS: The ability of both water and defatted methanol extracts to accelerate scratch wound closure in fibroblast cultures may support the traditional use of D. klainei stem bark in the treatment of skin lesions (such as burns) even if no antimicrobial activity was evidenced.


Subject(s)
Fibroblasts/drug effects , Magnoliopsida , Plant Extracts/pharmacology , Wound Healing/drug effects , Animals , Candida albicans/drug effects , Candida albicans/growth & development , Cell Line , Cells, Cultured , Escherichia coli/drug effects , Escherichia coli/growth & development , Humans , Mice , Microbial Sensitivity Tests , Plant Bark , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Streptococcus pyogenes/drug effects , Streptococcus pyogenes/growth & development
5.
Br J Cancer ; 105(9): 1370-8, 2011 Oct 25.
Article in English | MEDLINE | ID: mdl-21970875

ABSTRACT

BACKGROUND: Biliary tract cancer (BTC) and benign biliary strictures can be difficult to differentiate using standard tumour markers such as serum carbohydrate antigen 19-9 (CA19-9) as they lack diagnostic accuracy. METHODS: Two-dimensional difference gel electrophoresis and tandem mass spectrometry were used to profile immunodepleted serum samples collected from cases of BTC, primary sclerosing cholangitis (PSC), immunoglobulin G4-associated cholangitis and healthy volunteers. The serum levels of one candidate protein, leucine-rich α-2-glycoprotein (LRG1), were verified in individual samples using enzyme-linked immunosorbent assay and compared with serum levels of CA19-9, bilirubin, interleukin-6 (IL-6) and other inflammatory markers. RESULTS: We report increased LRG1, CA19-9 and IL-6 levels in serum from patients with BTC compared with benign disease and healthy controls. Immunohistochemical analysis also demonstrated increased staining of LRG1 in BTC compared with cholangiocytes in benign biliary disease. The combination of receiver operating characteristic (ROC) curves for LRG1, CA19-9 and IL-6 demonstrated an area under the ROC curve of 0.98. In addition, raised LRG1 and CA19-9 were found to be independent predictors of BTC in the presence of elevated bilirubin, C-reactive protein and alkaline phosphatase. CONCLUSION: These results suggest LRG1, CA19-9 and IL-6 as useful markers for the diagnosis of BTC, particularly in high-risk patients with PSC.


Subject(s)
Biliary Tract Neoplasms/diagnosis , CA-19-9 Antigen/blood , Cholangitis, Sclerosing/diagnosis , Cholangitis/diagnosis , Glycoproteins/blood , Interleukin-6/blood , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/analysis , Female , Humans , Male , Middle Aged
6.
Br J Cancer ; 98(10): 1675-81, 2008 May 20.
Article in English | MEDLINE | ID: mdl-18475301

ABSTRACT

Alterations in epithelial mucin expression are associated with carcinogenesis, but there are few data in biliary tract cancer (BTC). In pancreatic malignancy, MUC4 is a diagnostic and prognostic tumour marker, whereas MUC5AC has been proposed as a sensitive serological marker for BTC. We assessed MUC4 and MUC5AC expression in (i) prospectively collected bile and serum specimens from 72 patients with biliary obstruction (39 BTC) by real-time reverse transcriptase-PCR (qPCR) and western blot analysis, and (ii) 79 archived biliary tissues (69 BTC) by immunohistochemistry. In bile, MUC4 protein was detected in 27% of BTC and 29% of primary sclerosing cholangitis (PSC) cases, but not in other benign and malignant biliary diseases (P<0.01 and P=0.06). qPCR revealed a 1.9-fold increased MUC4 mRNA expression in BTC patients' bile compared with benign disease. In archived tissues, MUC4 protein was detected in 37% of BTC but in none of the benign samples (P=0.03). In serum, MUC5AC was found exclusively in BTC and PSC sera (44% and 13%, respectively; P<0.001 for BTC vs non-BTC) and correlated negatively with BTC survival. Biliary MUC4 and serum MUC5AC are highly specific tumour-associated mucins that may be useful in the diagnosis and formulation of therapeutic strategies in BTC.


Subject(s)
Bile/metabolism , Biliary Tract Neoplasms/metabolism , Biomarkers, Tumor/metabolism , Mucins/blood , Mucins/metabolism , Adult , Aged , Aged, 80 and over , Biliary Tract Neoplasms/blood , Biliary Tract Neoplasms/pathology , Biomarkers, Tumor/blood , Blotting, Western , Female , Follow-Up Studies , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Male , Middle Aged , Mucin 5AC , Mucin-4 , Neoplasm Staging , Predictive Value of Tests , Prospective Studies , Reverse Transcriptase Polymerase Chain Reaction
7.
J Hazard Mater ; 156(1-3): 466-71, 2008 Aug 15.
Article in English | MEDLINE | ID: mdl-18289775

ABSTRACT

In this work the screening results of the scientific activity conducted on laboratory scale to valorise chromium(III) contained in the galvanic sludge as chromium precursor for ceramic pigments are reported. The valorisation of this waste as a secondary raw material (SRM) is obtained by achievement of thermal and chemical stable crystal structures able to color ceramic material. Two different pigments pink CaCr(0.04)Sn(0.97)SiO(5) and green Ca(3)Cr(2)(SiO(4))(3) were synthesized by solid-state reactions using dried Cr sludge as chromium oxide precursor. The obtained pigments were characterized by X-ray diffraction and SEM analysis. Furthermore the color developed in a suitable ceramic glaze was investigated in comparison with the color developed by the pigments prepared from pure Cr(2)O(3). The characterization carried out corroborates the thermal and chemical stability of the synthesized pigments and, especially for the Cr-Sn pink pigment, the powders develop an intense color that is very similar to the color developed by the pigments obtained starting from pure Cr(2)O(3).


Subject(s)
Chromium/chemistry , Coloring Agents/chemical synthesis , Sewage , Microscopy, Electron, Scanning , X-Ray Diffraction
8.
J Hazard Mater ; 153(3): 1270-4, 2008 May 30.
Article in English | MEDLINE | ID: mdl-17980961

ABSTRACT

Bottom and fly ashes coming from the urban wastes incineration represent a by-product nowadays landfilled. By mixing different amount of these residues with others inert materials, such as glass cullet and feldspar waste, two vitrifiable mixtures are tailored. Glasses, obtained by means of vitrification process, are chemically stable with low leachability of contaminants and show comparable properties to those of commercial soda-lime glasses. Moreover, from the thermal and mechanical characterisation the tendency of these glasses to crystallise, for their transformation into glass-ceramic materials, has been evidenced.


Subject(s)
Carbon , Glass , Incineration , Industrial Waste , Particulate Matter , Refuse Disposal/methods , Ceramics , Coal Ash , Conservation of Natural Resources , Metals/analysis , Microscopy, Electron, Scanning
9.
Biochim Biophys Acta ; 1768(5): 1268-76, 2007 May.
Article in English | MEDLINE | ID: mdl-17320813

ABSTRACT

A novel approach to the study of RBCs based on the collection of three-dimensional high-resolution AFM images and on the measure of the surface roughness of their plasma membrane is presented. The dependence of the roughness from several parameters of the imaging was investigated and a general rule for a trustful analysis and comparison has been suggested. The roughness of RBCs is a morphology-related parameter which has been shown to be characteristic of the single cells composing a sample, but independent of the overall geometric shape (discocyte or spherocyte) of the erythrocytes, thus providing extra-information with respect to a conventional morphology study. The use of the average roughness value as a label of a whole sample was tested on different kinds of samples. Analyzed data revealed that the quantitative roughness value does not change after treatment of RBCs with various commonly used fixation and staining methods while a drastic decrease occurs when studying cells with membrane-skeletal alteration both naturally occurring or artificially induced by chemical treatments. The present method provides a quantitative and powerful tool for a novel approach to the study of erythrocytes structure through an ultrastructural morphological analysis with the potential to give information, in a non-invasive way, on the RBCs function.


Subject(s)
Cell Membrane/ultrastructure , Erythrocytes/ultrastructure , Microscopy, Atomic Force , Humans , Spherocytosis, Hereditary , Surface Properties
10.
J Nanosci Nanotechnol ; 6(3): 591-9, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16573109

ABSTRACT

A review is presented of the literature data concerning the effects induced by carbon nanoparticles on the biological environment and the importance of these effects in human and animal health. The discovery in 1985 of fullerenes, a novel carbon allotrope with a polygonal structure made up solely by 60 carbon atoms, and in 1991 of carbon nanotubes, thin carbon filaments (1-3 microm in length and 1-3 nm in diameter) with extraordinary mechanical properties, opened a wide field of activity in carbon research. During the last few years, practical applications of fullerenes as biological as well as pharmacological agents have been investigated. Various fullerene-based compounds were tested for biological activity, including antiviral, antioxidant, and chemiotactic activities. Nanotubes consist of carbon atoms arranged spirally to form concentric cylinders, that are perfect crystals and thinner than graphite whiskers. They are stronger than steel but very flexible and lightweight and transfer heat better than any other known material. These characteristics make them suitable for various potential applications such as super strong cables and tips for scanning probe microscopes, as well as biomedical devices for drug delivery, medical diagnostic, and therapeutic applications. The effects induced by these nanostructures on rat lung tissues, as well as on human skin and human macrophage and keratinocyte cells are presented.


Subject(s)
Biocompatible Materials/adverse effects , Foreign-Body Reaction/etiology , Lung Diseases/etiology , Nanotubes, Carbon/adverse effects , Risk Assessment/methods , Skin Diseases/etiology , Animals , Foreign-Body Reaction/prevention & control , Humans , Risk Factors
11.
J Hazard Mater ; 135(1-3): 149-55, 2006 Jul 31.
Article in English | MEDLINE | ID: mdl-16406335

ABSTRACT

Asbestos was widely used as a building material prior to the 1970's. It is well known that asbestos is a health hazard and its progressive elimination is a priority for pollution prevention. Asbestos can be transformed to non-hazardous silicate phases by microwave thermal treatment. The aim of this investigation is to describe the microwave inertization process of asbestos containing waste (ACW) and its recycling in porcelain stoneware tiles, porous single-fired wall tiles and ceramic bricks following industrial manufacture procedure. Inertised asbestos powder was added in the percentages of 1, 3, and 5 wt.% to commercially available compositions and then fired following industrial thermal cycles. Water absorption and linear shrinkage of the obtained industrial products do not present significant variations with additions up to 5 wt.% of microwave inertised ACW.


Subject(s)
Asbestos , Ceramics , Conservation of Natural Resources/methods , Industrial Waste , Microwaves , Asbestos/chemistry , Ceramics/chemistry , Chemical Phenomena , Chemistry, Physical , Microscopy, Electron, Scanning , Temperature , X-Ray Diffraction
12.
Waste Manag ; 25(2): 183-9, 2005.
Article in English | MEDLINE | ID: mdl-15737716

ABSTRACT

This work is concerned with open-loop recycling of end of life Cathode Ray Tubes glass (an unsolved problem when considering that in Europe almost 90% of EOL electronic goods is disposed of in landfills), focusing on the development of glass-ceramics from panel or funnel glass with dolomite and alumina, and the evaluation of the tendency towards crystallisation with particular attention on composition and thermal treatment. Glasses were melted at a temperature of about 1500 degrees C and transformed into glass-ceramics by different thermal treatments (900 degrees C to approximately 1100 degrees C temperature range and 0.5 to approximately 8h soaking time). By using the evaluation of thermal, mineralogical and microstructural data it has been pointed out that a good degree of crystallisation is reached at about 1000 degrees C and with a high proportion of waste glass (50-75%) if 40-45% of CaO and MgO bearer (dolomite) is introduced. In this way alkaline and alkaline-earth silicate and aluminosilicate mainly develop probably with a surface mechanism.


Subject(s)
Ceramics , Conservation of Natural Resources , Glass , Refuse Disposal/methods , Crystallization , Data Display , Electronics , Materials Testing , Temperature
13.
Cancer Chemother Pharmacol ; 46(2): 128-34, 2000.
Article in English | MEDLINE | ID: mdl-10972482

ABSTRACT

PURPOSE: Our previous work had shown that retinoic acid (RA) inhibits cell growth and induces apoptosis in estrogen receptor-positive (ER-positive) MCF-7 and T-47D human breast carcinoma cells, but not in ER-negative human breast carcinoma cells MB-231 and MB-453. The purpose of this work was to determine whether these differences might be due to differences in uptake and metabolism of the drug between ER-positive and ER-negative cells. METHODS: We measured RA uptake in cultured human breast cancer cells and determined its metabolism by high-pressure liquid chromatographic analysis. RESULTS: The two ER-positive cell lines reached maximum RA uptake at about 2 h, followed by a sharp decline, so that most RA had disappeared from the cells and from the medium by 24 h and was found as oxidation products in the culture medium. In contrast, the two ER-negative cell lines showed a pattern of lower accumulation without the sharp increase and subsequent steep decline, so that by 24 h there was more RA in these cells and their culture medium than in the RA-responsive ER-positive cells, even though at 2 h the ER-negative cells had taken up less RA than the ER-positive cells. Kinetic analysis of the uptake of RA in MCF-7 cells was consistent with rapid movement across the cell membranes and the actual rate determined by diffusion of albumin-bound retinoid to the cells. CONCLUSIONS: This study is the first to demonstrate profound differences in RA accumulation and confirms previous results on different rates of RA metabolism between ER-positive and ER-negative human breast cancer cells. The findings reported here, therefore, may introduce additional elements to be considered in the design of new drugs for cancer chemoprevention and therapy.


Subject(s)
Breast Neoplasms/metabolism , Receptors, Estrogen/physiology , Tretinoin/pharmacokinetics , Biological Transport , Blood Proteins/physiology , Chromatography, High Pressure Liquid , Culture Media , Female , Humans , Kinetics , Tritium , Tumor Cells, Cultured
14.
Carcinogenesis ; 21(7): 1271-9, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10874003

ABSTRACT

Retinoids are essential for the maintenance of epithelial differentiation. As such, they play a fundamental role in chemoprevention of epithelial carcinogenesis and in differentiation therapy. Physiological retinoic acid is obtained through two oxidation steps from dietary retinol, i.e. retinol-->retinal-->retinoic acid. The latter retinal-->retinoic acid step is irreversible and eventually marks disposal of this essential nutrient, through cytochrome P450-dependent oxidative steps. Mutant mice deficient in aryl hydrocarbon receptor (AHR) accumulate retinyl palmitate, retinol and retinoic acid. This suggests a direct connection between the AHR and retinoid homeostasis. Retinoids control gene expression through the nuclear retinoic acid receptors (RARs) alpha, beta and gamma and 9-cis-retinoic acid receptors alpha, beta and gamma, which bind with high affinity the natural ligands all-trans-retinoic acid and 9-cis-retinoic acid, respectively. Retinoids are effective chemopreventive agents against skin, head and neck, breast, liver and other forms of cancer. Differentiation therapy of acute promyelocytic leukemia (APL) is based on the ability of retinoic acid to induce differentiation of leukemic promyelocytes. Patients with relapsed, retinoid-resistant APL are now being treated with arsenic oxide, which results in apoptosis of the leukemic cells. Interestingly, induction of differentiation in promyelocytes and consequent remission of APL following retinoid therapy depends on expression of a chimeric PML-RAR alpha fusion protein resulting from a t(15;17) chromosomal translocation. This protein functions as a dominant negative against the function of both PML and RARs and its overexpression is able to recreate the phenotypes of the disease in transgenic mice. The development of new, more effective and less toxic retinoids, alone or in combination with other drugs, may provide additional avenues for cancer chemoprevention and differentiation therapy.


Subject(s)
Anticarcinogenic Agents/therapeutic use , Antineoplastic Agents/therapeutic use , Neoplasms/drug therapy , Neoplasms/prevention & control , Retinoids/therapeutic use , Animals , Cell Differentiation/drug effects , Humans , Neoplasms/pathology
15.
Biochem Biophys Res Commun ; 279(3): 920-4, 2000 Dec 29.
Article in English | MEDLINE | ID: mdl-11162450

ABSTRACT

Retinyl ester concentration is regulated by retinoic acid (RA) through an autoregulatory loop, which acts on lecithin:retinol acyltransferase (LRAT). We tested whether retinol esterification activity is downregulated in human mammary carcinoma cells and whether LRAT expression is RAR-regulated. Normal human mammary epithelial (HMEC) cells expressed a retinoid-upregulated 5-kb LRAT transcript and synthesized retinyl esters from 3H-retinol. Human carcinoma MCF-7 cells failed to express the 5-kb LRAT transcript and to synthesize retinyl esters. Instead, they expressed a 2.7-kb LRAT transcript. Both transcripts were upregulated by RA. Stable expression of the dominant-negative RARalpha403 blunted the up-regulation of LRAT mRNA by RA. We conclude that retinol esterification is decreased in MCF-7 vs normal mammary cells; that these cancer cells express a shorter (2.7 kb) LRAT transcript, and that retinoid receptors are involved in the regulation of LRAT-mediated retinyl ester synthesis by RA.


Subject(s)
Acyltransferases/metabolism , Vitamin A/metabolism , Acyltransferases/biosynthesis , Acyltransferases/genetics , Epithelial Cells/drug effects , Epithelial Cells/enzymology , Esterification , Humans , Molecular Weight , RNA, Messenger/drug effects , RNA, Messenger/metabolism , Receptors, Retinoic Acid/physiology , Retinoids/pharmacology , Transcription, Genetic , Tritium , Tumor Cells, Cultured , Up-Regulation/drug effects
16.
Carcinogenesis ; 20(6): 1133-5, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10357800

ABSTRACT

4-Hydroxyphenylretinamide (4-HPR) is a synthetic retinoid with minimal toxicity and favorable pharmacokinetics during long-term administration to patients in clinical trials. Since 4-HPR binds poorly to the retinoic acid receptors, the issue of whether 4-HPR exerts its biological actions via classical retinoid receptor pathways remains to be resolved. We have previously reported that stable expression of a truncated retinoic acid receptor alpha, RARalpha403, transduced in NIH 3T3 cells by a retroviral vector, rendered the cells resistant to retinoic acid for growth inhibition and induction of tissue transglutaminase (TGase II). Here, we report that stable expression of the dominant negative construct RARalpha403 fails to blunt growth inhibition and TGase II induction by 4-HPR, a potent chemopreventive retinoid, in the same cells. These data show that retinoic acid receptors do not mediate either growth inhibition or induction of TGase II activity by 4-HPR in mouse fibroblast cells.


Subject(s)
Cell Division/drug effects , Fenretinide/pharmacology , GTP Phosphohydrolases/biosynthesis , GTP-Binding Proteins , Signal Transduction , Transglutaminases/biosynthesis , Tretinoin/pharmacology , 3T3 Cells , Animals , Fibroblasts/drug effects , Fibroblasts/enzymology , Fibroblasts/metabolism , GTP Phosphohydrolases/genetics , Gene Expression Regulation, Enzymologic/drug effects , Mice , Protein Glutamine gamma Glutamyltransferase 2 , Transglutaminases/genetics
17.
Res Virol ; 149(5): 299-305, 1998.
Article in English | MEDLINE | ID: mdl-9879608

ABSTRACT

In this study, we analysed by transmission electron microscopy (TEM), sequential details of morphological modifications that accompanied viral morphogenesis in the lymphoblastoid cell line (LCL) TOFE infected in vitro with hepatitis C virus (HCV). As previously reported, we observed virus-like particles (VLPs) in cytoplasmic vesicles mainly located in the perinuclear region of infected cells. In this area, the Golgi apparatus and the endoplasmic reticulum (ER) appeared hyperplastic, remarkably enriched in vesicles and lysosomal structures. Furthermore, only in this perinuclear region, cytopathic-effect(CPE)-like changes seemed to originate, consisting in enlarged cytoplasmic vacuoles filled with degenerative amorphous material containing VLPs. Finally, the complete filling-up of the cytoplasm with these degenerative vacuoles, in addition to cellular lysis displayed by some cells, appeared as the possible terminal pattern of the infectious process. Our data suggest that in vitro HCV-infected TOFE cells undergo typical CPE-like changes that may be connected with virus replication.


Subject(s)
B-Lymphocytes/ultrastructure , B-Lymphocytes/virology , Cytopathogenic Effect, Viral , Hepacivirus/physiology , Cell Line , Cell Membrane/ultrastructure , Endoplasmic Reticulum/ultrastructure , Golgi Apparatus/ultrastructure , Humans , Inclusion Bodies, Viral/ultrastructure , Inclusion Bodies, Viral/virology , Microscopy, Electron , Vacuoles/ultrastructure
18.
Cancer Res ; 57(14): 2835-8, 1997 Jul 15.
Article in English | MEDLINE | ID: mdl-9230184

ABSTRACT

Livers from aryl hydrocarbon receptor-null mice showed a 3-fold increase in retinoids and a 65% decrease in retinoic acid metabolism. Levels of expression of the retinoic acid 4-hydroxylase, P450RAI, did not change, whereas cytochrome P4501A2 levels were lower in the null mouse, as shown earlier; however, this enzyme was found not to be active toward retinoic acid. These data suggest that aryl hydrocarbon receptor controls retinoic acid catabolism, through modulation of an unidentified target gene. Aldehyde dehydrogenases 1 and 2 were down-regulated markedly in the aryl hydrocarbon receptor-deficient mouse liver. 2,3,7,8-Tetrachlorodibenzo-p-dioxin induced cytochrome P4501A2 but not the aldehyde dehydrogenases in wild-type mice, suggesting that aryl hydrocarbon receptor is not involved directly in the down-regulation of this gene. Transglutaminase II, a retinoic acid-responsive gene product, was increased 2-fold, consistent with the liver fibrosis phenotype observed in the null mice. These findings suggest a molecular connection between xenobiotic-activated receptor signaling and retinoid homeostasis.


Subject(s)
Liver/metabolism , Receptors, Aryl Hydrocarbon/physiology , Retinoids/metabolism , Tretinoin/metabolism , Animals , Male , Mice , Mice, Knockout , Polychlorinated Dibenzodioxins/toxicity , Receptors, Aryl Hydrocarbon/genetics
19.
Cell Mol Biol (Noisy-le-grand) ; 42(8): 1229-42, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8997526

ABSTRACT

We have analyzed the pattern of time-dependent and concentration-dependent incorporation of Lucifer Yellow CH (LY) and Horseradish Peroxidase (HRP) by human umbilical vein endothelial cells cultured on a non-adhesive substratum, where they they become organized into stable, multicellular aggregates. The data were compared with those previously obtained from low-density cultures of non-growing endothelial cells adherent to plastic. While the linear trend of the incorporation kinetics is preserved, the rate of uptake with both time and concentrations is highly dependent on the culture conditions, namely typology of cell-cell and cell-substrate interactions. An at least two-fold increase of the rate of uptake was observed with both markers in the aggregated cells. The extracellular concentration of LY required to saturate the binding capacity of the cell surface shifts from approximately 0.25 mg/ml, with the adherent cells, to approximately 0.5 mg/ml in the aggregated cells; the rate of uptake of three different forms of HRP shows, besides a sharp quantitative increase, also qualitative variations, testified by differential changes of their incorporation rates. These results are entirely consistent with the assumption that the association of the endothelial cells into multicellular aggregates increases the rate of pinocytic uptake by modifying the physicochemical properties of the cell surface, thereby increasing its differential affinity for the extracellular markers.


Subject(s)
Endothelium, Vascular/physiology , Horseradish Peroxidase/metabolism , Isoquinolines/metabolism , Pinocytosis/physiology , Biological Transport , Cell Adhesion/physiology , Cell Aggregation , Cells, Cultured , Endothelium, Vascular/ultrastructure , Humans , Intercellular Junctions , Umbilical Veins/cytology
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