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1.
Sci Rep ; 11(1): 5119, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664428

RESUMO

Industrial development and increased energy requirements have led to high consumption of fossil fuels. Thus, environmental pollution has become a profound problem. Every year, a large amount of agro-industrial, municipal and forest residues are treated as waste, but they can be recovered and used to produce thermal and electrical energy through biological or thermochemical conversion processes. Among the main types of agro-industrial waste, soluble coffee residues represent a significant quantity all over the world. Silver skin and spent coffee grounds (SCG) are the main residues of the coffee industry. The many organic compounds contained in coffee residues suggest that their recovery and use could be very beneficial. Indeed, thanks to their composition, they can be used in the production of biodiesel, as a source of sugar, as a precursor for the creation of active carbon or as a sorbent for the removal of metals. After a careful evaluation of the possible uses of coffee grounds, the aim of this research was to show a broad characterization of coffee waste for energy purposes through physical and chemical analyses that highlight the most significant quality indexes, the interactions between them and the quantification of their importance. Results identify important tools for the qualification and quantification of the effects of coffee waste properties on energy production processes. They show that (SCG) are an excellent raw material as biomass, with excellent values in terms of calorific value and low ash content, allowing the production of 98% coffee pellets that are highly suitable for use in thermal conversion systems. Combustion tests were also carried out in an 80kWth boiler and the resulting emissions without any type of abatement filter were characterized.

2.
Parasite Immunol ; 40(5): e12527, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29569735

RESUMO

Human dendritic cells (DCs) show remarkable phenotypic changes when matured in the presence of helminth-derived products. These modifications frequently elicited a polarization towards Th2 cells and regulatory T cells thus contributing to immunological tolerance against these pathogens. In this study, the interaction between DCs and larvae of the zoonotic anisakid nematode Anisakis pegreffii was investigated. A. pegreffii larvae were collected from fish hosts, and monocyte-derived DCs were cocultured in the presence of the live larvae (L) or its crude extracts (CE). In both experimental conditions, A. pegreffii impacted DC viability, hampered DC maturation by reducing the expression of molecules involved in antigen presentation and migration (ie HLA-DR, CD86, CD83 and CCR7), increased the phagosomal radical oxygen species (ROS) levels and modulated the phosphorylation of ERK1,2 pathway. These biological changes were accompanied by the impairment of DCs to activate a T-cell-mediated IFNγ. Interestingly, live larvae appeared to differently modulate DC secretion of cytokines and chemokines as compared to CE. These results demonstrate, for the first time, the immunomodulatory role of A. pegreffii on DCs biology and functions. In addition, they suggest a dynamic contribution of DCs to the induction and maintenance of the inflammatory response against A. pegreffii.


Assuntos
Anisaquíase/imunologia , Anisakis/imunologia , Apresentação de Antígeno/imunologia , Células Dendríticas/imunologia , Alimentos Marinhos/parasitologia , Animais , Anisaquíase/parasitologia , Anisaquíase/patologia , Diferenciação Celular/imunologia , Decapodiformes/parasitologia , Células Dendríticas/citologia , Peixes/parasitologia , Humanos , Imunomodulação , Interferon gama/imunologia , Larva/imunologia , Sistema de Sinalização das MAP Quinases/imunologia , Espécies Reativas de Oxigênio/metabolismo
3.
Br J Dermatol ; 177(6): 1633-1643, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28580633

RESUMO

BACKGROUND: Transforming growth factor (TGF)-ß1 exerts inhibitory effects on keratinocyte proliferation. OBJECTIVES: To examine whether Smad7, a known inhibitor of TGF-ß1 signalling, is involved in psoriasis-associated keratinocyte hyperproliferation. METHODS: Smad7 was evaluated in skin sections of patients with psoriasis and healthy controls and in mice with Aldara-induced skin pathology by real-time polymerase chain reaction and immunohistochemistry. To assess whether Smad7 positively regulates in vivo keratinocyte growth, mice treated with Aldara received daily cutaneous administration of Smad7 antisense oligonucleotide (AS). Keratin (K)6 and K16, cell-cycle-associated factors, cell-cycle and cell proliferation were evaluated in HaCaT cells either treated with Smad7 AS or transfected with Smad7 plasmid and in mice given Smad7 AS. RESULTS: Smad7 was highly expressed in keratinocytes of patients with psoriasis and of mice treated with Aldara. In HaCaT cells, Smad7 knockdown inhibited cell growth, reduced K6 and K16 expression and promoted accumulation of cells in the S-phase of the cell cycle. Smad7-deficient keratinocytes exhibited reduced levels of CDC25A protein, a phosphatase that facilitates progression of cells through the S-phase, and hyperphosphorylation of eukaryotic initiation factor 2 (eIF2)α, a negative regulator of CDC25 protein translation. Consistently, Smad7 overexpression in HaCaT cells was followed by induction of K6 and K16 and increased cell proliferation. Topical application of Smad7 AS to Aldara-treated mice reduced epidermal thickness. CONCLUSIONS: Our data show that Smad7 is overexpressed in human and murine psoriasis and suggest a key role of this molecule in the control of keratinocyte proliferation.


Assuntos
Proliferação de Células/fisiologia , Queratinócitos/patologia , Psoríase/patologia , Proteína Smad7/fisiologia , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Animais , Dermatite/fisiopatologia , Relação Dose-Resposta a Droga , Epiderme/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Camundongos Endogâmicos C57BL , Transdução de Sinais/fisiologia , Proteína Smad7/deficiência , Regulação para Cima/fisiologia
4.
Parasite Immunol ; 39(7)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28475216

RESUMO

IgE sensitization to Anisakis pegreffii in Italian subjects suffering from gastro-allergic anisakiasis (GAA) (N=5), or showing chronic urticaria (CU+) after fish consumption (N=100), was investigated. A control group (N=5) was also included. IgE response was analysed by immunoblotting (WB) assay, using both excretory/secretory products (ESPs) and crude extract (CE) of A. pegreffii larvae. The results were compared with those achieved by the conventional immunological method for Anisakis allergy (ie, immunoCAP). Among the 110 subjects, 28 showed IgE positivity with both WB and iCAP methods; 13 proved IgE reactivity, in WB assay, to ESP antigens of A. pegreffii, here provisionally indicated as Ani s 1-like, Ani s 7-like, Ani s 13-like; only 15 sera have shown IgE-WB reaction to Ani s 7-like and Ani s 13-like. iCAP and WB exhibited a high concordance value (κ=1.00) when iCAP value was <0.35 (negative result) and >50.0 (positive result). In the sera samples recorded as positive to Anisakis allergy, Ani s 1-like was responsible for 46.4% of the sensitivity, while Ani s 7-like and Ani s 13-like for 100%. They could be considered as major antigens in the diagnosis of allergic anisakiasis caused by A. pegreffii.


Assuntos
Anisaquíase/diagnóstico , Anisakis/imunologia , Anticorpos Anti-Helmínticos/imunologia , Antígenos de Helmintos/imunologia , Hipersensibilidade/diagnóstico , Imunoglobulina E/sangue , Adulto , Alérgenos/imunologia , Animais , Anisaquíase/imunologia , Anisaquíase/parasitologia , Anisakis/isolamento & purificação , Feminino , Peixes/parasitologia , Proteínas de Helminto/imunologia , Humanos , Hipersensibilidade/imunologia , Hipersensibilidade/parasitologia , Immunoblotting , Itália , Masculino , Especificidade da Espécie , Adulto Jovem
5.
J Environ Manage ; 183(Pt 3): 754-762, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27649608

RESUMO

This study investigates the relationship between fine resolution, local-scale biophysical and socioeconomic contexts within which land degradation occurs, and the human responses to it. The research draws on experimental data collected under different territorial and socioeconomic conditions at 586 field sites in five Mediterranean countries (Spain, Greece, Turkey, Tunisia and Morocco). We assess the level of desertification risk under various land management practices (terracing, grazing control, prevention of wildland fires, soil erosion control measures, soil water conservation measures, sustainable farming practices, land protection measures and financial subsidies) taken as possible responses to land degradation. A data mining approach, incorporating principal component analysis, non-parametric correlations, multiple regression and canonical analysis, was developed to identify the spatial relationship between land management conditions, the socioeconomic and environmental context (described using 40 biophysical and socioeconomic indicators) and desertification risk. Our analysis identified a number of distinct relationships between the level of desertification experienced and the underlying socioeconomic context, suggesting that the effectiveness of responses to land degradation is strictly dependent on the local biophysical and socioeconomic context. Assessing the latent relationship between land management practices and the biophysical/socioeconomic attributes characterizing areas exposed to different levels of desertification risk proved to be an indirect measure of the effectiveness of field actions contrasting land degradation.


Assuntos
Conservação dos Recursos Naturais , Mineração de Dados/métodos , Política Ambiental , Agricultura , Política Ambiental/economia , Incêndios , Grécia , Humanos , Marrocos , Análise de Componente Principal , Fatores Socioeconômicos , Solo , Espanha , Tunísia , Turquia , Abastecimento de Água
6.
Oncogene ; 34(27): 3493-503, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25174402

RESUMO

Colorectal cancers (CRCs) often show a dense infiltrate of cytokine-producing immune/inflammatory cells. The exact contribution of each immune cell subset and cytokine in the activation of the intracellular pathways sustaining CRC cell growth is not understood. Herein, we isolate tumor-infiltrating leukocytes (TILs) and lamina propria mononuclear cells (LPMCs) from the tumor area and the macroscopically unaffected, adjacent, colonic mucosa of patients who underwent resection for sporadic CRC and show that the culture supernatants of TILs, but not of LPMCs, potently enhance the growth of human CRC cell lines through the activation of the oncogenic transcription factors signal transducer and activator of transcription 3 (STAT3) and nuclear factor-kappa B (NF-kB). Characterization of immune cell complexity of TILs and LPMCs reveals no differences in the percentages of T cells, natural killer T cells, natural killer (NK) cells, macrophages and B cells. However, T cells from TILs show a functional switch compared with those from LPMCs to produce large amounts of T helper type 17 (Th17)-related cytokines (that is, interleukin-17A (IL-17A), IL-17F, IL-21 and IL-22), tumor necrosis factor-α (TNF-α) and IL-6. Individual neutralization of IL-17A, IL-17F, IL-21, IL-22, TNF-α or IL-6 does not change TIL-derived supernatant-driven STAT3 and NF-kB activation, as well as their proproliferative effect in CRC cells. In contrast, simultaneous neutralization of both IL-17A and TNF-α, which abrogates NF-kB signaling, and IL-22 and IL-6, which abrogates STAT3 signaling, reduces the mitogenic effect of supernatants in CRC cells. IL-17A, IL-21, IL-22, TNF-α and IL-6 are also produced in excess in the early colonic lesions in a mouse model of sporadic CRC, associated with enhanced STAT3/NF-kB activation. Mice therapeutically given BP-1-102, an orally bioavailable compound targeting STAT3/NF-kB activation and cross-talk, exhibit reduced colon tumorigenesis and diminished expression of STAT3/NF-kB-activating cytokines in the neoplastic areas. These data suggest that strategies aimed at the cotargeting of STAT3/NF-kB activation and interaction between them might represent an attractive and novel approach to combat CRC.


Assuntos
Neoplasias Colorretais/patologia , Interleucina-17/farmacologia , Interleucina-6/farmacologia , Interleucinas/farmacologia , NF-kappa B/genética , Fator de Transcrição STAT3/genética , Fator de Necrose Tumoral alfa/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Cultivadas , Neoplasias Colorretais/genética , Citocinas/metabolismo , Citocinas/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Interleucinas/metabolismo , Camundongos , Camundongos Transgênicos , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Th17/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Interleucina 22
7.
Mucosal Immunol ; 7(6): 1467-79, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24850427

RESUMO

In inflammatory bowel disease (IBD), tissue damage is driven by an excessive immune response, poorly controlled by counter-regulatory mechanisms. SIRT1, a class III NAD+-dependent deacetylase, regulates negatively the expression of various proteins involved in the control of immune-inflammatory pathways, such as Stat3, Smad7, and NF-κB. Here we examined the expression, regulation, and function of SIRT1 in IBD. SIRT1 RNA and protein expression was less pronounced in whole biopsies and lamina propria mononuclear cells (LPMCs) of IBD patients in comparison with normal controls. SIRT1 expression was downregulated in control LPMC by tumor necrosis factor (TNF)-α and interleukin (IL)-21, and upregulated in IBD LPMC by neutralizing TNF-α and IL-21antibodies. Consistently, SIRT1 expression was increased in mucosal samples taken from IBD patients successfully treated with Infliximab. Treatment of IBD LPMC with Cay10591, a specific SIRT1 activator, reduced NF-κB activation and inhibited inflammatory cytokine synthesis, whereas Ex527, an inhibitor of SIRT1, increased interferon (IFN)-γ in control LPMC. SIRT1 was also reduced in mice with colitis induced by 2,4,6-trinitrobenzenesulphonic acid or oxazolone. Cay10591 prevented and cured experimental colitis whereas Ex527 exacerbated disease by modulating T cell-derived cytokine response. Data indicate that SIRT1 is downregulated in IBD patients and colitic mice and suggest that SIRT1 activation can help attenuate inflammatory signals in the gut.


Assuntos
Regulação Enzimológica da Expressão Gênica/imunologia , Doenças Inflamatórias Intestinais/imunologia , Intestinos/imunologia , Sirtuína 1/imunologia , Adjuvantes Imunológicos/efeitos adversos , Adjuvantes Imunológicos/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Feminino , Regulação Enzimológica da Expressão Gênica/genética , Humanos , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Infliximab , Interferon gama/genética , Interferon gama/imunologia , Interleucinas/genética , Interleucinas/imunologia , Intestinos/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Oxazolona/efeitos adversos , Oxazolona/farmacologia , Sirtuína 1/genética , Ácido Trinitrobenzenossulfônico/toxicidade , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
8.
Cell Death Dis ; 5: e1073, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24556688

RESUMO

Initially identified as an inhibitor of transforming growth factor (TGF)-ß mainly owing to its ability to bind TGF-ß receptor type I and abrogate TGF-ß-driven signaling, Smad7 can interact with additional intracellular proteins and regulate TGF-ß-independent pathways, thus having a key role in the control of neoplastic processes in various organs. Genome-wide association studies have shown that common alleles of Smad7 influence the risk of colorectal cancer (CRC), even though the contribution of Smad7 in colon carcinogenesis is not fully understood. In this study, we assessed the expression and role of Smad7 in human and mouse models of sporadic CRC. We document a significant increase of Smad7 in human CRC relative to the surrounding nontumor tissues and show that silencing of Smad7 inhibits the growth of CRC cell lines both in vitro and in vivo after transplantation into immunodeficient mice. Knockdown of Smad7 results in enhanced phosphorylation of the cyclin-dependent kinase (CDK)2, accumulation of CRC cells in S phase and enhanced cell death. Smad7-deficient CRC cells have lower levels of CDC25A, a phosphatase that dephosphorylates CDK2, and hyperphosphorylated eukaryotic initiation factor 2 (eIF2)α, a negative regulator of CDC25 protein translation. Consistently, knockdown of Smad7 associates with inactivation of eIF2α, lower CDC25A expression and diminished fraction of proliferating cells in human CRC explants, and reduces the number of intestinal tumors in Apc(min/+) mice. Altogether, these data support a role for Smad7 in sustaining colon tumorigenesis.


Assuntos
Proliferação de Células , Neoplasias do Colo/metabolismo , Proteína Smad7/metabolismo , Animais , Sobrevivência Celular , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias do Colo/prevenção & controle , Quinase 2 Dependente de Ciclina/metabolismo , Modelos Animais de Doenças , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Genes APC , Genes RAG-1 , Terapia Genética , Células HCT116 , Células HT29 , Células Hep G2 , Humanos , Camundongos , Camundongos Transgênicos , Oligonucleotídeos Antissenso/metabolismo , Fosforilação , Transdução de Sinais , Fatores de Tempo , Transfecção , Fosfatases cdc25/metabolismo
9.
Carbohydr Polym ; 101: 307-12, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24299778

RESUMO

In this paper Enhanced Variational Iteration Method, EVIM is proposed, along with the BPES, for solving Bratu equation which appears in the particular elecotrospun nanofibers fabrication process framework. Elecotrospun organic nanofibers, with diameters less than 1/4 microns have been used in non-wovens and filtration industries for a broad range of filtration applications in the last decade. Electro-spinning process has been associated to Bratu equation through thermo-electro-hydrodynamics balance equations. Analytical solutions have been proposed, discussed and compared.

10.
J Agric Saf Health ; 16(3): 141-59, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20836436

RESUMO

Agricultural workers are exposed to various risks, including chemical agents, noise, and many other factors. One of the most characteristic and least known risk factors is constituted by the microclimatic conditions in the different phases of work (in field, in greenhouse, etc). A typical condition is thermal stress due to high temperatures during harvesting operations in open fields or in greenhouses. In Italy, harvesting is carried out for many hours during the day, mainly in the summer, with temperatures often higher than 30 degrees C. According to ISO 7243, these conditions can be considered dangerous for workers' health. The aim of this study is to assess the risks of exposure to microclimatic conditions (heat) for fruit and vegetable harvesters in central Italy by applying methods established by international standards. In order to estimate the risk for workers, the air temperature, radiative temperature, and air speed were measured using instruments in conformity with ISO 7726. Thermodynamic parameters and two more subjective parameters, clothing and the metabolic heat production rate related to the worker's physical activity, were used to calculate the predicted heat strain (PHS) for the exposed workers in conformity with ISO 7933. Environmental and subjective parameters were also measured for greenhouse workers, according to ISO 7243, in order to calculate the wet-bulb globe temperature (WBGT). The results show a slight risk for workers during manual harvesting in the field. On the other hand, the data collected in the greenhouses show that the risk for workers must not be underestimated. The results of the study show that, for manual harvesting work in climates similar to central Italy, it is essential to provide plenty of drinking water and acclimatization for the workers in order to reduce health risks. Moreover, the study emphasizes that the possible health risks for greenhouse workers increase from the month of April through July.


Assuntos
Doenças dos Trabalhadores Agrícolas/epidemiologia , Transtornos de Estresse por Calor/epidemiologia , Temperatura Alta/efeitos adversos , Doenças dos Trabalhadores Agrícolas/prevenção & controle , Temperatura Corporal , Produtos Agrícolas/classificação , Frutas , Transtornos de Estresse por Calor/etiologia , Transtornos de Estresse por Calor/prevenção & controle , Humanos , Itália/epidemiologia , Microclima , Postura , Medição de Risco , Temperatura , Verduras
11.
J Agric Saf Health ; 16(2): 87-98, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20503810

RESUMO

Tomatoes are the most common crop in Italy. The production cycle requires operations in the field and factory that can cause musculoskeletal disorders due to the repetitive movements of the upper limbs of the workers employed in the sorting phase. This research aims to evaluate these risks using the OCRA (occupational repetitive actions) index method This method is based firstly on the calculation of a maximum number of recommended actions, related to the way the operation is performed, and secondly on a comparison of the number of actions effectively carried out by the upper limb with the recommended calculated value. The results of the risk evaluation for workers who manually sort tomatoes during harvest showed a risk for the workers, with an exposure index greater than 20; the OCRA index defines an index higher than 3.5 as unacceptable. The present trend of replacing manual sorting onboard a vehicle with optical sorters seems to be appropriate to reduce the risk of work-related musculoskeletal disorders (WMSDs) and is supported from both a financial point of view and as a quality control measure.


Assuntos
Agricultura/estatística & dados numéricos , Transtornos Traumáticos Cumulativos/complicações , Ergonomia/estatística & dados numéricos , Doenças Musculoesqueléticas/etiologia , Exposição Ocupacional/efeitos adversos , Transtornos Traumáticos Cumulativos/epidemiologia , Transtornos Traumáticos Cumulativos/prevenção & controle , Feminino , Humanos , Itália/epidemiologia , Solanum lycopersicum , Modelos Biológicos , Modelos Estatísticos , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/prevenção & controle , Postura , Fatores de Risco , Local de Trabalho/estatística & dados numéricos
12.
J Viral Hepat ; 11(4): 302-9, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15230852

RESUMO

Chronic hepatitis C virus (HCV) infection is associated with the development of lymphoproliferative disorders (LPDs). The aim of this investigation was to determine the prevalence and characterization of monoclonal gammopathy and benign and malignant LPDs in individuals with chronic hepatitis C. A total of 233 subjects diagnosed with chronic hepatitis C (male/female ratio: 131/102, median age; 49 years) were studied. Serum and urine were examined for the presence of a monoclonal gammopathy. A bone marrow aspirate and biopsy was obtained in individuals with a monoclonal gammopathy. Thirty-two patients (13.7%, 32 of 233) had a monoclonal gammopathy; 75% of them were benign and were not associated with malignant disorders (24 of 32) while 25% were associated with malignant LPDs or a plasma cell disorder (eight of 32). Two additional subjects without monoclonal gammopathy were diagnosed as having a malignant LPDs. The prevalence of malignant LPDs/plasma cell disorder in individuals with HCV-induced chronic liver disease was 4.3%. No difference was found in terms of disease duration, HCV genotype, viral load, alanine aminotransferase level or histopathologic score between the subjects with or without a monoclonal gammopathy. The presence of mixed cryoglobulinaemia was strongly associated with the presence of an underlying malignant disorder. Hence a monoclonal gammopathy is found in 14% of patients with chronic hepatitis C and is associated with malignant B-cell LPD in more than a quarter of such patients. The prevalence of LPDs in individuals with HCV-induced chronic liver disease is greater than that of the normal healthy population.


Assuntos
Hepatite C Crônica/complicações , Transtornos Linfoproliferativos/complicações , Adulto , Idoso , Alanina Transaminase/sangue , Medula Óssea/patologia , Crioglobulinemia/complicações , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Fígado/patologia , Transtornos Linfoproliferativos/epidemiologia , Masculino , Pessoa de Meia-Idade , Gamopatia Monoclonal de Significância Indeterminada/complicações , Paraproteinemias/complicações , Plasmócitos/patologia , Prevalência , Fatores de Risco , Carga Viral
13.
Dig Liver Dis ; 34 Suppl 2: S34-6, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12408437

RESUMO

Recent observations demonstrate that enteropathogenetic and enterohaemorrhagic bacteria, as well as other non enteropathogenetic bacteria (Listeria, Coxiella Burnetii), may subvert the host cell cytoskeleton. Models from enteropathogenic bacteria demonstrate that cytoskeletal proteins are required for bacteria binding to the enterocytes and that they play a role in the immune response of the host to intestinal bacteria. The cytoskeletal protein family Tropomyosins is present in all eukaryotic cells, with multiple isoforms regulated by multiple genes. Of the different Tropomyosin isoforms, TM5 has been shown to be expressed in colonic and jejunal epithelial cells, while TM1 in colonic and jejunal smooth muscle. In vitro studies have shown the presence of serum and mucosal IgG against TM5 in almost two thirds of patients with ulcerative colitis, suggesting: a. a possible autoimmune response to Tropomyosin in these patients; b. the hypothesis that the development of pouchitis may be related to the expression of TM5 in the ileal pouch; c. the use of probiotics in the treatment of pouchitis. Overall, the new expression of cytoskeletal proteins on the cell surface appears to be possibly induced by several mechanisms, including intestinal bacteria and apoptosis. The expression of cytoskeletal proteins on the cell surface may induce tolerance or autoimmune response on target cells. Further investigations are, however needed on the possible role of cytoskeletal proteins in human diseases.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Intestinos/microbiologia , Humanos , Pouchite/etiologia , Pouchite/terapia , Probióticos/uso terapêutico , Tropomiosina/metabolismo
14.
Int J Artif Organs ; 25(10): 960-5, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12456037

RESUMO

Long-term maintenance of viability and expression of differentiated hepatocyte function is crucial for bioartificial liver support. We developed a new bioreactor design (ALEX), associated with a new extracellular autologous hepatocyte biomatrix (Porcine Autologous Biomatrix - PBM) support. To test this new bioreactor, we compared it to a standard BAL (BioArtificial Liver) cartridge in a ex vivo model using human plasma added to bilirubin, ammonium and lidocaine. A pathology study was performed on both bioreactors. The results suggest that ALEX allows a maximal contact between the perfusing plasma and the liver cells and a proper hepatocyte support by a cell-to-matrix attachment. ALEX is a suitable cell support bioreactor, guaranteeing long-term maintenance of the metabolic activity of hepatocytes when compared to a standard BAL cartridge.


Assuntos
Circulação Extracorpórea , Fígado Artificial , Amônia/sangue , Animais , Bilirrubina/sangue , Reatores Biológicos , Hepatócitos , Humanos , Lidocaína/sangue , Tempo de Protrombina , Suínos , Engenharia Tecidual
15.
Mol Cell Endocrinol ; 193(1-2): 85-8, 2002 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-12161006

RESUMO

There is considerable evidence that reactive oxygen species (ROS) have a causative role in chronic hepatic injury and cancer development via direct and indirect mechanisms. Estrogens produce free oxygen radicals through redox cycling and affect cell proliferation, also in the liver. We are presently involved in evaluating the possible relationship between estrogens receptor expression, type of receptor, oxidative DNA damage and c-myc in chronic liver disease. The data on DNA adducts, c-myc mRNA and variant estrogen receptor in patients with HCV- or HBV-related chronic liver disease are suggesting that those positive for variant liver estrogen receptor present higher genomic oxidative damage, as reflected in 8-OHdG levels. We are also observing that patients with chronic hepatitis and cirrhosis, when positive for variant estrogen receptor, present higher c-myc m-RNA expression, a factor reportedly associated with increased genomic instability, augmented cytoproliferation and carcinogenesis. Our own and other author's data are shedding new light on estrogen pathophysiology, liver damage and hepatic cancer.


Assuntos
Hepatopatias/metabolismo , Estresse Oxidativo/fisiologia , Receptores de Estrogênio/fisiologia , Animais , Dano ao DNA , Hepatite Viral Humana , Humanos , Hepatopatias/patologia , Hepatopatias/virologia
16.
Am J Gastroenterol ; 96(10): 2973-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11693335

RESUMO

OBJECTIVE: Coinfection with hepatitis B (HBV) and hepatitis C (HCV) viruses is associated with a more severe liver disease, increased frequency in the development of hepatocellular carcinoma, and resistance to interferon (IFN) therapy when performed with the standard dosages used in single infections. In the attempt to verify whether the outcome of IFN therapy in patients with hepatitis B and hepatitis C coinfection can be improved, we have planned a prospective, randomized trial with medium to high dosages of interferon three times a week for 6 months. METHODS: Thirty patients with HBV-HCV coinfection, and chronic hepatitis were randomized to receive either 6 or 9 MU alpha-interferon three times a week for 6 months. Patients were HBsAg positive, anti-HBe positive, HBV DNA negative by dot blot (6/30 positive by polymerase chain reaction), and anti-HCV-positive, HCV RNA positive. Pretreatment and posttreatment liver biopsies were performed. RESULTS: Five patients treated with 9 MU IFN consistently cleared HCV RNA and HBV DNA, whereas none of those treated with 6 MU reacted in a similar fashion (p = 0.045). Responders showed significant improvement of histological activity index in comparison with nonresponders (mean Ishak score pretreatment versus posttreatment p = 0.002). Long term follow-up showed that none of the patients treated with high doses developed cirrhosis whereas 4/14 treated with low doses did develop cirrhosis. CONCLUSION: Even though the percentage was not very high, the sustained response, the striking histological improvement, and the lack of development of cirrhosis achieved in these patients, indicate that with HBV-HCV coinfection, a trial with high doses of interferon is strongly recommended.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Idoso , Antivirais/administração & dosagem , Esquema de Medicação , Feminino , Hepatite B Crônica/diagnóstico , Hepatite C Crônica/diagnóstico , Humanos , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
17.
J Viral Hepat ; 8(5): 372-6, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11555195

RESUMO

Hepatitis B virus (HBV) vaccination is recommended for individuals with chronic liver disease. However, the response to standard doses of hepatitis B vaccines in such individuals has been poor. The aim of the present study was to assess the response to high-dose short-interval HBV vaccination in individuals with chronic liver disease of different aetiologies. A total two hundred and 24 subjects with chronic liver disease (138 chronic active hepatitis and 86 cirrhosis) and 26 healthy controls were vaccinated using a high-dose (40 microg) short-interval (monthly for 3 consecutive months) HBV vaccination schedule. One hundred and thirty-eight of the 224 subjects with chronic liver disease (62%) seroconverted to anti-HBs antibody positivity (>10 mIU/mL) after the third dose of vaccine as compared with 24 of the 26 controls (92%) (P < 0.01). The response rate was reduced in individuals with cirrhosis (36/86, 42%), particularly in alcohol-induced cirrhosis (2/17, 12%), as compared with individuals with chronic hepatitis (102/138, 74%) (P < 0.001). No significant HBV vaccination-related adverse effects were seen in individuals with or without cirrhosis as well as in the controls. High-dose short-interval HBV vaccination is safe and efficacious in individuals with chronic liver disease. The response to HBV vaccination is reduced in cirrhotics, particularly those with alcoholic cirrhosis. These data suggest that HBV vaccination should be accomplished early in an individual cause of chronic liver disease prior to the development of cirrhosis.


Assuntos
Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Feminino , Hepatite/sangue , Hepatite/imunologia , Hepatite/patologia , Hepatite/terapia , Anticorpos Anti-Hepatite/imunologia , Vacinas contra Hepatite B/efeitos adversos , Hepatite B Crônica/sangue , Hepatite B Crônica/terapia , Hepatite C Crônica/sangue , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Hepatite C Crônica/terapia , Humanos , Esquemas de Imunização , Imunoterapia , Cirrose Hepática/sangue , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Masculino , Pessoa de Meia-Idade
18.
Endocrine ; 14(2): 213-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11394639

RESUMO

Fetal alcohol syndrome usually implies effects on the offspring of maternal EtOH consumption during gestation, with fewer reports addressing the impact of paternal exposure on the progeny. One previous report has dealt with the impact of EtOH exposure on peripubertal male rats as a model of teenage drinking and the deleterious effects on the offspring. We report here findings examining the effect of 2 mo of EtOH feeding on male animals as they progressed through puberty on their ability to impregnate EtOH-naive female rats and characteristics of the subsequent litters. The EtOH-imbibing fathers weighed significantly less than pairfed controls and animals ingesting a non-EtOH liquid diet ad libitum. Nevertheless, they were able to mate successfully, although fecundity was significantly reduced. The number of successful pregnancies, defined as carried to term, was diminished from 92% in controls to 75% in EtOH-fed animals (p < 0.05). There was increased paternal testicular oxidative injury demonstrated by enhanced lipid peroxidation, protein oxidation, and decreased ratio of reduced to oxidized glutathione. The litter size of the EtOH-exposed males was reduced by 46%. The average litter size was 12.4+/-1.5 pups/litter in ad libitum animals, virtually identical to the 12.5+/-0.6 pups/litter in the pair fed controls. This is in sharp contrast to the 6.7+/-0.1 pups/litter from the paternal EtOH matings (p < 0.001). There was an increase in the average individual weight of pup offspring of paternally EtOH-exposed animals (p < 0.01 vs pair-fed controls and p < 0.05 vs ad libitum). Curiously, the male-to-female pup ratio was altered with a higher preponderance of male offspring from EtOH-fed fathers. There were no gross malformations noted among the pups. Insulin-like growth factor-1 levels in the pups at 10 d of age were unaltered between the groups. However, leptin was significantly elevated in the EtOH offspring. It appears that chronic EtOH exposure in the peripubertal fathers subsequently decreases fecundity and that this may be mediated by testicular oxidative injury, perhaps leading to accelerated germ cell apoptosis.


Assuntos
Etanol/administração & dosagem , Etanol/efeitos adversos , Pai , Maturidade Sexual , Animais , Animais Recém-Nascidos/sangue , Feminino , Glutationa/metabolismo , Infertilidade Masculina/induzido quimicamente , Fator de Crescimento Insulin-Like I/análise , Leptina/análise , Peroxidação de Lipídeos , Tamanho da Ninhada de Vivíparos , Masculino , Oxirredução , Estresse Oxidativo , Gravidez , Ratos , Ratos Sprague-Dawley , Testículo/metabolismo
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