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1.
Leuk Res Rep ; 15: 100243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34040959

RESUMO

Major disease complications for patients with essential thrombocythemia (ET) include thrombosis and fibrotic or leukemic transformation. Calreticulin (CALR) mutation type 1 frequencies in ET are estimated between 7% and 11% and ET patients carrying CALR type 1 mutation are associated with lower risk of thrombosis but higher risk of myelofibrosis transformation compared to ET patients with JAK2 mutation. Leukemic transformation rates at 20 years are estimated at less than 5% for ET and risk factors for leukemic transformation are advanced age, thrombosis history, leukocytosis, and anemia. Amongst the subtypes of blast phase myeloproliferative neoplasms, acute promyelocytic leukemia is extremely rare. Herein, we present a case of a promyelocytic blast crisis of post-ET myelofibrosis with associated life-threatening splanchnic vein thrombosis. This case suggests that inflammation plays a key role in thrombotic events and fibrotic/leukemic transformation in ET patients, regardless the molecular landscape.

2.
Br J Dermatol ; 166(5): 948-52, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22233400

RESUMO

BACKGROUND: Neoplastic T-cell recruitment into the skin is a critical step in the pathogenesis of mycosis fungoides (MF), and the cutaneous T-cell attracting chemokine, CTACK/CCL27, might be involved. OBJECTIVES: To investigate the clinical and prognostic significance of CTACK/CCL27 levels in patients with early-stage MF. METHODS: Serum samples and skin biopsy specimens were collected from 15 patients at the time of diagnosis and after the end of treatment with psoralen plus ultraviolet A/interferon alfa-2b combination therapy. Serum samples were also collected from 20 healthy donors as controls. CTACK/CCL27 serum levels were analysed by enzyme-linked immunosorbent assays. CTACK/CCL27 tissue expression was determined by immunohistochemistry on skin biopsy specimens taken at diagnosis and after therapy. Event-free survival was taken as the primary clinical outcome. RESULTS: In patients with MF at diagnosis, CTACK/CCL27 serum levels were not significantly different from healthy controls, whereas CTACK/CCL27 expression in the skin was increased in 87% of cases compared with normal controls. After therapy, all patients obtained a clinical complete remission, serum levels did not change significantly and tissue expression remained abnormal in 80% of patients, even if complete histological remission was recorded. Serum levels were not significantly different in cases with different intensity of cutaneous immunostaining. Eight patients experienced a relapse: the combination of high CTACK/CCL27 levels both in sera and skin increased the probability of experiencing an event at 51 months from 36% to 83%. CONCLUSIONS: Our data seem to indicate that CTACK/CCL27 levels in skin and sera after therapy might be correlated with risk of recurrence.


Assuntos
Antineoplásicos/uso terapêutico , Quimiocina CCL27/metabolismo , Interferon-alfa/uso terapêutico , Micose Fungoide/tratamento farmacológico , Terapia PUVA/métodos , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Micose Fungoide/sangue , Recidiva Local de Neoplasia/etiologia , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
3.
Cell Mol Biol (Noisy-le-grand) ; 53 Suppl: OL965-80, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17695086

RESUMO

The in vitro biological response to fluoro-edenite (FE) fibres, an asbestos-like amphibole, was evaluated in lung alveolar epithelial A549, mesothelial MeT-5A and monocyte-macrophage J774 cell lines. The mineral has been found in the vicinity of the town of Biancavilla (Catania, Sicily), where an abnormal incidence of mesothelioma has been documented. Cell motility, distribution of polymerized actin, and synthesis of vascular endothelial growth factor (VEGF) and of beta-catenin, critical parameters for tumour development, progression and survival, were investigated in A549 and MeT-5A cells exposed to 50 microg/ml FE fibres for 24 hr and 48 hr. The levels of cyclooxygenase (COX-2) and prostaglandin (PGE2), two molecules involved in cancer pathogenesis by affecting mitogenesis, cell adhesion, immune surveillance and apoptosis, were measured in J774 cells treated with FE fibres under the same experimental conditions. Finally, FE fibres were studied by SEM and EDS analysis to investigate their chemical composition. Exposure of A549 and MeT-5A cells to FE fibres affected differentially phalloidin-stained cytoplasmic F-actin networks, cell motility and VEGF and beta-catenin expression according to the different sensitivity of the two cell lines. In J774 cells it induced a significant increase in COX-2 expression, as assessed by Western blot analysis, and in the concentration of PGE2, measured in culture media by ELISA. SEM-EDS investigations demonstrated two types of FE fibres, edenite and fluoro-edenite, differing in chemical composition and both recognizable as calcic amphiboles. Fibre width ranged from less than 1 microm (prevalently 0.5 microm) to 2-3 microm (edenite) up to several microm (fluoro-edenite); length ranged from about 6 to 80 microm (edenite) up to some hundred microm (fluoro-edenite). Results provide convincing evidence that FE fibres are capable of inducing in vitro functional modifications in a number of parameters with crucial roles in cancer development and progression. Inhaled FE fibres have the potential to induce mesothelioma, even though their ability to penetrate lung alveoli depends on their aerodynamic diameter.


Assuntos
Amiantos Anfibólicos/toxicidade , Pulmão/efeitos dos fármacos , Actinas/metabolismo , Animais , Amiantos Anfibólicos/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/análise , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/análise , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Formazans/metabolismo , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Pulmão/citologia , Pulmão/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Mesotelioma/metabolismo , Camundongos , Fibras Minerais , Sais de Tetrazólio/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , beta Catenina/biossíntese
4.
Cell Mol Biol (Noisy-le-grand) ; 52 Suppl: OL905-13, 2007 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-17543227

RESUMO

Asbestos fibers, such as chrysotile and crocidolite, are known to have cytotoxic effects on different cell types. In vivo exposure to asbestos fibers can induce both fibrotic and malignant lung diseases , however, the mechanisms linking exposure to the subsequent development of the diseases are unknown. Numerous investigations suggest the involvement of reactive oxygen species (ROS). ROS are known to damage biological macromolecules including proteins, cell membrane lipids and nucleic acids; alterations of these essential cellular components can alter cell function and can drive the cell to neoplastic transformation or to cell death. Because the mitochondrial respiratory chain is an important source of ROS and RNS (reactive nitogen species) in the cells, we have investigated the effects of aqueous extracts of asbestos (natural and synthetic) fibers on some mitochondrial activities. Our data show that crocidolite fibers release substances in solution that may interfere directly with the mitochondrial cytochrome oxidase complex. Moreover, the calcium ions released from these fibers induce opening of the permeability transition pore of the inner membrane leading to a possible cytotoxic effect due to the release of apoptotic factors normally localized in the mitochondrial intermembrane space. In addition, crocidolite extracts enhance the mitochondrial production of ROS. No significant biochemical effects are exerted by chrysotile, either natural or synthetic, on isolated mitochondria. Nevertheless, all asbestos fibers tested induce morphological alterations visualized by transmission electron microscopy and morphometric analysis.


Assuntos
Asbesto Crocidolita/toxicidade , Mitocôndrias/efeitos dos fármacos , Animais , Asbesto Crocidolita/química , Cálcio/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Complexo IV da Cadeia de Transporte de Elétrons/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
5.
Med Biol Eng Comput ; 43(2): 196-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15865127

RESUMO

Rapid prototyping, automatic image processing (computer-aided design (CAD)) and computer-aided manufacturing techniques are opening new and interesting prospects for medical devices and tissue engineering, especially for hard tissues such as bone. The development of a bone high-resolution scaffold prototype using these techniques is described. The results testify to the fidelity existing between microtomographic reconstruction and CAD. Furthermore, stereolithographic manufacturing of this scaffold, which possesses a high degree of similarity to the starting model as monitored by morphological evaluations (mean diameter 569 +/- 147 microm), represents a promising result for regenerative medicine applications.


Assuntos
Substitutos Ósseos , Desenho Assistido por Computador , Engenharia Tecidual/métodos , Durapatita , Análise de Elementos Finitos , Humanos , Tomografia Computadorizada por Raios X/métodos
6.
Cell Mol Biol (Noisy-le-grand) ; 50 Online Pub: OL691-700, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15607050

RESUMO

Asbestos fibers, such as chrysotile and crocidolite, are known to have cytotoxic effects on different cell types. in vivo exposure to asbestos fibers can induce both fibrotic and malignant lung diseases , however, the mechanisms linking exposure to the subsequent development of the diseases are unknown. Numerous investigations suggest the involvement of reactive oxygen species (ROS). ROS are known to damage biological macromolecules including proteins, cell membrane lipids and nucleic acids; alterations of these essential cellular components can alter cell function and can drive the cell to neoplastic transformation or to cell death. Because the mitochondrial respiratory chain is an important source of ROS and RNS (reactive nitogen species) in the cells, we have investigated the effects of aqueous extracts of asbestos (natural and synthetic) fibers on some mitochondrial activities. Our data show that crocidolite fibers release substances in solution that may interfere directly with the mitochondrial cytochrome oxidase complex. Moreover, the calcium ions released from these fibers induce opening of the permeability transition pore of the inner membrane leading to a possible cytotoxic effect due to the release of apoptotic factors normally localized in the mitochondrial intermembrane space. In addition, crocidolite extracts enhance the mitochondrial production of ROS. No significant biochemical effects are exerted by chrysotile, either natural or synthetic, on isolated mitochondria. Nevertheless, all asbestos fibers tested induce morphological alterations visualized by transmission electron microscopy and morphometric analysis.


Assuntos
Asbesto Crocidolita/toxicidade , Asbestos Serpentinas/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Animais , Apoptose , Cálcio/farmacologia , Complexo IV da Cadeia de Transporte de Elétrons/análise , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Íons/farmacologia , Masculino , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Hepáticas/ultraestrutura , Dilatação Mitocondrial , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo
7.
Cell Mol Biol (Noisy-le-grand) ; 50 Online Pub: OL517-26, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15555416

RESUMO

The morpho-functional and energy condition of NCTC 2544 cells exposed for 1 hr to a high concentration of H2O2 (500 microM) was studied at 4 and 24 hr to investigate the short- and medium-term biomolecular mechanisms affecting energetic mitochondrial capability. Morphometric data obtained from ultrastructural investigations clearly showed significant modifications of the different mitochondrial parameters--numerical density (Nv), volume density (Vv) and Vv/Nv ratio, in interkinetic, apoptotic and mitotic cells after H2O2 exposure (from 4 to 24 hr). These results were confirmed by the detection at 24 hr of mitochondrial cytochrome c release in the cytosol, indicating impairment in mitochondrial membrane permeability. Data supporting these observations were obtained from the MTT test which showed reduced cell viability in H2O2 treated cultures at 4 hr and an even greater decrement at 24 hr. In conclusion our data imply that significant cause-effect relationships exist between the toxicity of reactive oxygen species (i.e. 500 microM H2O2) and morpho-structural mitochondrial damage in interkinetic, apoptotic and mitotic cells, respectively. They support previous results present both in the literature and also in one of our earlier papers which show that early nuclear DNA damage could initiate mitochondrial or intrinsic apoptotic pathway after H2O2 exposure.


Assuntos
Peróxido de Hidrogênio/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Estresse Oxidativo , Apoptose , Linhagem Celular , Citocromos c/análise , Citosol/química , Complexo IV da Cadeia de Transporte de Elétrons/análise , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/ultraestrutura , Mitocôndrias/enzimologia , Mitose/efeitos dos fármacos , Oxidantes/farmacologia , Succinato Desidrogenase/análise
8.
Int J Artif Organs ; 26(1): 73-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12602472

RESUMO

Owing to their possible carcinogenic effect, asbestos and other silica derivatives have been identified as priority substances for risk reduction and prevention of pollution. Neutralisation procedures have thus become a topical research subject in many European and American countries. In the present study, silica derivatives (asbestos-containing and asbestos substitutes like slag wool, rock wool, cement asbestos) were fully impregnated with an epoxy resin according to the procedure used for the in situ impregnation with viscous polymeric media, which penetrate and cement the fibres in place and reduce the risk of their dispersion in air. Untreated and treated samples were used to investigate their in vitro interaction with a human continuous epithelial cell line (NCTC 2544 keratinocytes) and test the resin's efficiency in passivating the surface activity of the fibrous particulate. SEM and morpho-quantitative data evidenced that impregnation with the epoxy resin modifies the mineral fibres' bioactivity (reduction of cell adhesion and decreased spread/round cell ratio) and demonstrated the value of in vitro cell testing after passivation as a risk-assessment procedure. These tests could be used for the rapid determination of the level of passivation of new synthetic mineral fibrous materials subjected to resin impregnation.


Assuntos
Amianto/efeitos adversos , Células Epiteliais/efeitos dos fármacos , Poluentes Ocupacionais do Ar/efeitos adversos , Amianto/química , Linhagem Celular , Sobrevivência Celular , Células Epiteliais/fisiologia , Células Epiteliais/ultraestrutura , Humanos
9.
Int J Artif Organs ; 26(12): 1077-85, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14738191

RESUMO

Biocompatibility relies essentially on surface phenomena, represented by cell-cell, cell-material and material (polymer)-protein interactions. An in vivo and in vitro experimental investigation was carried out on the biomaterials of two different classes with a good potential for in situ utilisation. Non-resorbable (Polypyrrole, Polyaniline, Polyimide) and resorbable (PLLA-PDXO-PLLA) materials for tissue engineering were studied for their overall tissue tolerance and cellular interactions. These non-resorbable polymers conceived for biosensor applications and implantable drug-delivery systems are intrinsically conductive. The PLLA-PDXO-PLLA triblock copolymer showed interesting tensile properties for bone and cartilage tissue engineering due to the presence of 1,5-dioxepan-2-one. In vitro and in vivo parallel studies showed an interesting correspondence: a) the cells in contact with the resorbable material that appeared to be capable of migratory-regenerative aspects in vitro exhibited good compatibility in vivo; whereas b) the non-resorbable materials, which are designed to remain in situ in vivo, were seen to have the potential to represent an adverse factor (inflammation, fibrotic reactions) that correlated with some aspects of cell behaviour in vitro.


Assuntos
Materiais Biocompatíveis/farmacologia , Queratinócitos/efeitos dos fármacos , Implantes Absorvíveis , Compostos de Anilina/farmacologia , Animais , Técnicas de Cultura de Células , Linhagem Celular , Feminino , Compostos Heterocíclicos/farmacologia , Humanos , Queratinócitos/fisiologia , Queratinócitos/ultraestrutura , Teste de Materiais , Poliésteres/farmacologia , Polímeros/farmacologia , Pirróis/farmacologia , Ratos , Ratos Sprague-Dawley , Resinas Sintéticas/farmacologia , Resistência à Tração
10.
Int J Artif Organs ; 25(9): 892-8, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12403406

RESUMO

Surface topography is important in establishing tissue organisation adjacent to implants, smooth surfaces generally being associated with fibrous encapsulation. By virtue of its large hydrated molecular volume and its capacity to form molecular matrix, hyaluronic acid can expand the interfibrillar collagen spaces to allow the movement of cells, although it can also hamper their locomotion. Low molecular-weight hyaluronan can also stimulate cell proliferation, especially at low concentrations. The aim of the present work was to evaluate in vitro the growth and migratory behaviour of NCTC 2544 keratinocytes cultured on different materials microstructured with hyaluronic acid or sulfated hyaluronic acid to assess the possibility of using these devices in the repair process of soft tissues. Ultrastructural morphological analyses, morphometric evaluations and detection of cytoskeletal elements were performed. Our observations provide evidence that micrometer-size parallel grooves of hyaluronic acid can influence cell growth behaviour since cells seeded onto the microstructured substrate arranged themselves according to a shape and an orientation that clearly reflected the chemotropism exerted on them by the two forms of acid. These data also highlight the importance of accurate microtexture fabrication. We intend to follow up these in vitro studies with in vivo experimental applications using PET and gelatin substrates structured with HyalS to evaluate wound healing responses, and to extend our investigations of the cytoskeletal modifications induced by different microstructures.


Assuntos
Adjuvantes Imunológicos/farmacologia , Ácido Hialurônico/farmacologia , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Cicatrização/efeitos dos fármacos
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