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1.
Med Lav ; 107(1): 29-36, 2016 Jan 20.
Artigo em Italiano | MEDLINE | ID: mdl-26822244

RESUMO

BACKGROUND: In 2013 the International Journal of Surgical Pathology published a case report of intrasplenic malignant mesothelioma (MM) in a 48-year-old man: it was the first report in literature describing a case of primitive intra-splenic MM, described without  a history of asbestos exposure. OBJECTIVE: To verify the possible past exposure to asbestos, ignored by the patient himself, by studying in depth his environmental and occupational history. METHODS: Information about the occupational and non-occupational history of the subject was collected by Experts of the Operational Unit of Occupational Health and Safety Control (UOC PSAL) of the Local Health Unit Umbria 1 - Perugia, using the Italian National Mesothelioma Register (ReNaM) questionnaire and guide lines; an inspection was  carried out at the past canning industry where the patient worked in the period 1982-1990 and material was taken to be analysed by MOCF and SEM. RESULTS: Samples showed the presence of asbestos  fibres belonging to the amphibole class (amosite and crocidolite) and to the serpentine class (chrysotile). CONCLUSIONS: The survey described the past occupational exposure to asbestos in a canning industry, where  the subject worked in the period 1982-1990,  unknown to the patient himself. The authors strongly confirm the  usefulness of standardized methods, such as the ReNaM Questionnaire, and the importance of technical expertise of the investigator to find and analyse the suspect materials and to demonstrate  possible past occupational exposure to asbestos.


Assuntos
Amianto/efeitos adversos , Carcinógenos , Embalagem de Alimentos , Neoplasias Pulmonares/etiologia , Anamnese , Mesotelioma/etiologia , Neoplasias Esplênicas/etiologia , Amianto Amosita/efeitos adversos , Asbesto Crocidolita/efeitos adversos , Asbestos Serpentinas/efeitos adversos , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Mesotelioma/diagnóstico , Mesotelioma Maligno , Pessoa de Meia-Idade , Medição de Risco , Neoplasias Esplênicas/diagnóstico
2.
Med Lav ; 105(1): 63-73, 2014.
Artigo em Italiano | MEDLINE | ID: mdl-24552095

RESUMO

BACKGROUND: Starting from a project aimed at assessing the carcinogenic risk in some industrial sectors covered by Local Health Authority No.1 (LHA) in Perugia (USL Umbria1, Italian acronym), worksites for abatement of materials containing asbestos (MCA) were examined in order to estimate respirable fibres exposure levels in workers. Abatement work is, indeed, a fast developing sector, but is not free from asbestos risks in the long-term, particularly carcinogenic risks; this kind of work therefore requires maximum effort in respecting prevention standards prescribed in the relative legislation. OBJECTIVES: The aim of the research was to define the personal levels of exposure to respirable fibres and to create a reliable database for the interpretation of possible asbestos-related cases of neoplasms that may occur in the future in workers of this important occupational sector. METHODS: The authors took in consideration operations both on compact MCA and on friable MCA. In the case of compact MCA, exposure values measured by the LHA via their own sampling were compared to those measured by the companies involved in the project. In the case of friable MCA, however, sampling was only performed by the LHA and the assessment covered not only workers' exposure levels but also the pollution levels in the areas in the vicinity of the work site. RESULTS: In the case of compact MCA, results showed moderate average values of personal fibre exposure, and always considerably lower than the limit values (100 fibres/litre) prescribed by law (Legislative Decree 81/08); however, the average values detected by the LHA (15,8 fibres/litre) were significantly higher (p < 0.001) than those detected by companies (4,9 fibres/litre). In the case of friable MCA, however, average personal exposure values of workers (106,8 fibres/litre) were even higher than the limit values prescribed by current regulations, while in areas near the work sites, average fibre pollution levels (1,04 fibres/litre) were always very low and lacked significant variations (p > 0.05) during the different phases of work. CONCLUSIONS: According to the authors, the data collected show how in MCA abatement operations a carcinogenic risk in the long-term is in any case present, and this both in compact MCA work, where not all the prevention measures were accurately observed, and even more so, in friable MCA work, where average exposure levels of workers showed a heavy trend to exceed the above mentioned limit values. Considering the different evolution of the results of sampling carried out by the LHA and by the companies, the authors also highlight the need to provide mandatory technical guidelines for industrial hygiene laboratories so that sampling and analysis methods are as homogeneous as possible, thus making the results of research easily comparable.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Amianto/efeitos adversos , Exposição por Inalação/efeitos adversos , Fibras Minerais/efeitos adversos , Exposição Ocupacional/efeitos adversos , Poluentes Ocupacionais do Ar/análise , Amianto/análise , Humanos , Exposição por Inalação/análise , Itália , Fibras Minerais/análise , Exposição Ocupacional/análise
3.
J Biol Regul Homeost Agents ; 27(3): 805-16, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24152845

RESUMO

Cadmium (Cd), an ubiquitous environmental metal, mainly used for industrial purposes, may be toxic at level of the reproductive system. Testis tubular-based Sertoli cells (SC), play a major role in constituting the blood-testis barrier and provide a unique microenvironment for the genesis and differentiation of germ cells. Hence SC strictly control sperm qualitative and quantitative parameters. We aimed to assess whether exposure to Cd would adversely affect superior mammal SC viability and function. We isolated and purified SC from pre-pubertal pig testes according to our method and incubated the retrieved cells with three different Cadmium chloride concentrations (5-10-15 microM). Parameters of SC function such as inhibin B and anti-Mullerian hormone (AMH) were depressed by Cd exposure, contrary to what observed in untreated controls. No impairment of the FSH receptor integrity on the SC, as assessed by 17-beta-estradiol production, upon stimulation with FSH, was observed in either 5 microM Cd-treated or untreated controls. Differences, on the contrary, were observed for higher Cd concentrations (10 and 15 mM), in terms of FSH receptor integrity, that was altered, as compared to untreated controls, in terms of lower production of 17-beta-estradiol. In addition, the apoptotic test showed a significant increase of early (ANNEXIN V-/Propidium Iodide+) (AV-/PI+) and late apoptotic cells (AV+/ PI+) in all Cd -treated SC conditions as compared to controls. In conclusion, the Cd -related toxicity on SC, clearly demonstrated by our study, even at low concentrations, is expected to damage spermatogenesis that directly is dependent upon retention of SC viability and function.


Assuntos
Cádmio/toxicidade , Células de Sertoli/efeitos dos fármacos , Animais , Hormônio Antimülleriano/metabolismo , Apoptose/efeitos dos fármacos , Cádmio/farmacocinética , Sobrevivência Celular/efeitos dos fármacos , Inibinas/metabolismo , Masculino , Receptores do FSH/efeitos dos fármacos , Receptores do FSH/fisiologia , Células de Sertoli/fisiologia , Suínos
4.
J Biol Regul Homeost Agents ; 26(4): 681-92, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23241118

RESUMO

Crystal micro-morphology and dimension of silica particles could be responsible for the high prevalence of silicosis as recently found among goldsmiths. In the present study we investigated two samples of silica particles with different surface sizes and shapes for their capacity to induce changes in ECM component production. In addition we investigated if their different effects could be related to cytotoxicity and apoptotic effects. Human bronchial epithelial cells were cultured with or without a sample of Silica used for casting gold jewellery, named in our experiments Silica P or a commercial sample of Silica with different physical and chemical properties, named in our experiments Silica F. After 48 h of exposure PCR analysis determined levels of several matrix components. As induction of the apoptosis cascade, annexin assay, caspase 3 activity and cellular cytoxicity by MTT assay were assayed. Silica F promoted fibronectin, MMP12, tenascin C and Integrins b5 gene expressions more than Silica P. Silica P stimulated more TGFß1 and its TGFßR1 receptor than Silica F. Cytotoxic effects were induced by the two samples of Silica. On the contrary, no alteration in classic apoptotic marker protein expression was observed in presence of either Silica F or Silica P, suggesting silica particles affect ECM production and metalloproteases through a mechanism that does not involve apoptotic activation. Different Silica micromorphology and TGFß signal pathway are linked to lung fibrotic effects but the potential role Silica in apoptotic and toxic reaction remains to be ascertained.


Assuntos
Brônquios/efeitos dos fármacos , Proteínas da Matriz Extracelular/metabolismo , Dióxido de Silício/toxicidade , Brônquios/citologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Fibronectinas/genética , Humanos , Integrina alfa5/genética , Metaloproteinase 12 da Matriz/genética , Metaloproteinase 13 da Matriz/genética , Tamanho da Partícula
5.
J Biol Regul Homeost Agents ; 21(3-4): 97-104, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18261261

RESUMO

The small dimension and particle shape of silica in gypsum used to prepare moulds for lost wax casting might be responsible for the high prevalence of silicosis in gold jewellery. To test this hypothesis, human pulmonary epithelial cell (BEAS-2B) cultures were exposed to two samples of silica with different crystal micro-morphologies: Silica Powder (Silica P) which is used in casting gold jewellery, and no powder Silica (Silica F). Extracellular matrix (ECM) production was evaluated using radio-labelled precursors and quantified by RT-PCR analysis. Expression of basic fibroblast growth factor (FGF2) and its receptor (FGFR2) was also evaluated. The results demonstrated Silica P particles had a very fine lamellar crystalline structure while Silica F was characterized by larger rounded crystals. Silica P stimulated collagen production significantly more than Silica F and downregulated laminin and metalloprotease expression. Both silica samples down-regulated FGF2 but only Silica F enhanced FGF2 receptor expression. In conclusion each Silica sample promoted a profibrotic lung microenvironment in a different manner and also elicited different FGF2 signalling pathways. The data confirm that different micromorphology of Silica particles affects the fibrogenic potential and the molecular mechanisms of dust pathogenicity.


Assuntos
Células Epiteliais/efeitos dos fármacos , Matriz Extracelular/metabolismo , Mucosa Respiratória/citologia , Dióxido de Silício/farmacologia , Brônquios/citologia , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Colágeno/biossíntese , Colágeno Tipo IV/genética , Colágeno Tipo V/genética , Decorina , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Proteínas da Matriz Extracelular/genética , Fator 2 de Crescimento de Fibroblastos/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Laminina/genética , Metaloproteinase 2 da Matriz/genética , Microscopia Eletrônica , Tamanho da Partícula , Proteoglicanas/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Dióxido de Silício/química , Silicose/metabolismo , Silicose/patologia
6.
Mol Med ; 7(2): 83-92, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11471549

RESUMO

BACKGROUND: Previous studies show that macrophages, lung fibroblasts, and their soluble mediators are responsible for the onset and development of pulmonary fibrosis. This study was conducted to determine whether airway epithelial cells are also directly involved in response to fibrogenic agents and consequently in the pathogenesis of lung fibrosis. To verify the hypothesis, we determined whether silica acts directly on human bronchial epithelial cells by stimulating cytokine and growth factor release and by modifying matrix production. MATERIALS AND METHODS: An SV40 large T antigen-transformed human airway epithelial cell line, 16HBE14o (16HBE), was used. The expression profile of some proinflammatory interleukins (ILs), such as IL-1alpha, IL-1beta and IL-6 and their modulation by silica, were evaluated by polymerase chain reaction (PCR) analysis. Transforming growth factor beta (TGFbeta) and basic fibroblast growth factor (bFGF) mRNA levels were tested by Northern blotting in the presence and in the absence of silica. The silica- and/or bFGF-induced effects on matrix components (total proteins, collagen, and fibronectin) were also evaluated using radio-labeled precursors. RESULTS: The results demonstrated 16HBE internalized silica particles. Silica induced a little IL-6 secretion, without affecting IL-1 and TGFbeta isoform production and strongly stimulated bFGF mRNA level and bFGF protein secretion. Silica also induced changes in 16HBE production of total proteins, collagen, and fibronectin production. When added in combination with the growth factor, it strengthened bFGF stimulation of matrix component secretion. CONCLUSIONS: These results support the hypothesis that the changes in matrix components are due to a direct effect of silica on bronchial epithelial cells. Silica-induced over-secretion of bFGF suggests that autocrine and paracrine differentiation loops for bFGF may also be operative and that these mechanisms may be involved in the pathogenesis of pulmonary fibrosis. In the future, cytokine-directed therapeutic strategies might find a place in clinical practice.


Assuntos
Brônquios/citologia , Células Epiteliais/citologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Dióxido de Silício/farmacologia , Northern Blotting , Brônquios/efeitos dos fármacos , Divisão Celular , Células Cultivadas , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/efeitos dos fármacos , Fibronectinas/metabolismo , Humanos , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Microscopia Eletrônica , Microscopia de Fluorescência , Reação em Cadeia da Polimerase , Isoformas de Proteínas , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
J Investig Med ; 49(2): 146-56, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11288755

RESUMO

BACKGROUND: Silicosis, a pneumoconiosis marked by interstitial pulmonary fibrosis, is caused by inhalation of free crystalline silica particles. When silica particles are injected into the lower lung, they are translocated across the epithelium into the interstitial space, where macrophage-derived growth factors affect lung fibroblast proliferation and collagen deposition. We hypothesized that silica may act directly on pulmonary fibroblasts modifying extracellular matrix (ECM) synthesis and that the effects of silica may be mediated by transforming growth factor-beta (TGFbeta) overproduction. METHODS: To test this hypothesis, we studied a human lung fibroblast cell line (WI-1003) exposed to silica in vitro. We investigated cell morphology by electron microscopic procedure, cell growth, collagen production, and glycosaminoglycans (GAG) composition by radiolabeled precursors. Cytokine and growth factor synthesis were evaluated by specific enzyme-linked immunoadsorbent assay kits and Northern blotting analysis. RESULTS: Pulmonary fibroblasts internalized silica particles without detectable cell damage. Silica directly stimulated collagen synthesis and decreased the amount of 3H-glucosamine-labeled GAG. Silica-treated fibroblasts secreted less TGFbeta than untreated controls, antagonized the stimulatory effect of TGFbeta on ECM synthesis, and reversed TGFbeta-induced inhibition of cell proliferation. Northern blotting analysis showed increased interleukin-1alpha (IL-1alpha) mRNA after silica treatment. IL-1alpha had no influence on collagen synthesis but increased the number of WI-1003 fibroblasts. CONCLUSIONS: These results support our hypothesis that lung fibroblasts are direct silica targets. However, contradicting our hypothesis, silica antagonized TGFbeta activities through a TGFbeta downregulation and an IL-1alpha upregulation. The complex pattern of TGFbeta and IL-1alpha regulation in pulmonary fibroblasts is imbalanced by silica exposure and might play a key role in silica-mediated pulmonary fibrosis.


Assuntos
Matriz Extracelular/metabolismo , Pulmão/efeitos dos fármacos , Dióxido de Silício/toxicidade , Fator de Crescimento Transformador beta/antagonistas & inibidores , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/biossíntese , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Glicosaminoglicanos/biossíntese , Humanos , Interleucina-1/genética , Interleucina-1/farmacologia , Pulmão/metabolismo , RNA Mensageiro/análise , Fator de Crescimento Transformador beta/biossíntese
10.
Acta Vitaminol Enzymol ; 2(5-6): 163-70, 1980.
Artigo em Italiano | MEDLINE | ID: mdl-7293869

RESUMO

The cause of the Premature Infant Anemia (PIA) is mainly an insufficient erythropoiesis, a shorter mean-life of the red cells and in increased hemolysis. On these basis of prophylaxis has been attempted by treating newborns with folic acid, alpha-tocopherol and vitamins B1, B2, B6 and C. 208 premature babies have been treated (birth weight higher than 1750 nr. 171; birth weight less than 1750 nr. 37). Several parameters have been evaluated: weight gain, erythrocyte and reticulocyte count, jaundice occurrence and number of transfusions needed. The results on the blood parameters was good for the small babies group and sufficient for the others. Differences have been observed between the two groups for the occurrence of jaundice and transfusions.


Assuntos
Anemia Neonatal/tratamento farmacológico , Ácido Ascórbico/uso terapêutico , Ácido Fólico/uso terapêutico , Recém-Nascido Prematuro , Complexo Vitamínico B/uso terapêutico , Vitamina E/uso terapêutico , Anemia Neonatal/complicações , Peso Corporal , Contagem de Eritrócitos , Eritropoese , Humanos , Recém-Nascido , Icterícia Neonatal/complicações
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