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1.
Immunol Res ; 61(1-2): 79-89, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25582758

RESUMO

The emerging epidemic of Hodgkin and non-Hodgkin lymphomas worldwide continues to defy our understanding and forces the search for the causative factors. Adjuvants are known to act as triggers of immune and inflammatory responses. Animal experiments have demonstrated that long-term inflammation is related to aggravation of the immune network resulting in cellular and humoral responses leading to autoimmunity and lymphoma development. Chronic stimulation of the immune system is thought to be the key mechanism through which infectious diseases as well as autoimmune diseases can lead to lymphomagenesis. Many adjuvants can act similarly perturbing immune system's function, inducing a state of prolonged immune activation related to chronic lymphatic drainage. Several mechanisms were proposed by which adjuvants induce inflammation, and they are discussed herein. Some of them are triggering inflammasome; others bind DNA, lipid moieties in cells, induce uric acid production or act as lipophilic and/or hydrophobic substances. The sustained inflammation increases the risk of genetic aberrations, where the initial polyclonal activation ends in monoclonality. The latter is the hallmark of malignant lymphoma. Thus, chronic adjuvant stimulation may lead to lymphoma.


Assuntos
Adjuvantes Imunológicos/efeitos adversos , Linfoma/etiologia , Adjuvantes Imunológicos/química , Adjuvantes Farmacêuticos , Alumínio/efeitos adversos , Animais , Doenças Autoimunes/complicações , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/imunologia , Autoimunidade , Modelos Animais de Doenças , Humanos , Interações Hidrofóbicas e Hidrofílicas , Hipersensibilidade/complicações , Hipersensibilidade/imunologia , Inflamação/complicações , Inflamação/diagnóstico , Inflamação/imunologia , Risco , Compostos de Silício/efeitos adversos , Síndrome , Vacinação/efeitos adversos
3.
Biomed Res Int ; 2014: 312901, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24967352

RESUMO

Silicon carbide (SiC), a compound of silicon and carbon, with chemical formula SiC, the beta modification ( ß-SiC), with a zinc blende crystal structure (similar to diamond), is formed at temperature below 1700°C. ß-SiC will be the most suitable ceramic material for the future hard tissue replacement, such as bone and tooth. The in vitro cytotoxicity of ß-SiC nanowires was investigated for the first time. Our results indicated that 100 nm long SiC nanowires could significantly induce the apoptosis in MC3T3-E1 cells, compared with 100 µm long SiC nanowires. And 100 nm long SiC nanowires increased oxidative stress in MC3T3-E1 cells, as determined by the concentrations of MDA (as a marker of lipid peroxidation) and 8-OHdG (indicator of oxidative DNA damage). Moreover, transmission electron microscopy (TEM) was performed to evaluate the morphological changes of MC3T3-E1 cells. After treatment with 100 nm long SiC nanowires, the mitochondria were swelled and disintegrated, and the production of ATP and the total oxygen uptake were also decreased significantly. Therefore, ß-SiC nanowires may have limitations as medical material.


Assuntos
Apoptose/efeitos dos fármacos , Compostos Inorgânicos de Carbono/efeitos adversos , Peroxidação de Lipídeos/efeitos dos fármacos , Nanofios/efeitos adversos , Osteoblastos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Compostos de Silício/efeitos adversos , Animais , Compostos Inorgânicos de Carbono/farmacologia , Linhagem Celular , Teste de Materiais/métodos , Camundongos , Osteoblastos/patologia , Compostos de Silício/farmacologia
4.
Occup Environ Med ; 70(11): 803-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23852098

RESUMO

OBJECTIVES: To investigate the relationship between dust exposure and annual change in lung function among employees in Norwegian silicon carbide (SiC) plants using a quantitative job exposure matrix (JEM) regarding total dust. METHODS: All employees, 20-55 years of age by inclusion (n=456), were examined annually for up to 5 years (1499 examinations). Spirometry was performed at each examination, and a questionnaire encompassing questions of respiratory symptoms, smoking status, job and smoking history, and present job held was completed. A JEM was constructed based on 1970 personal total dust exposure measurements collected during the study period. The association between lung function and total dust exposure was investigated using linear mixed models. RESULTS: The annual change in forced expiratory volume (FEV) in one second per squared height, FEV1/height(2), per mg/m(3) increase in dust exposure was -2.3 (95% CI -3.8 to -0.79) (mL/m(2))×year(-1). In an employee of average height (1.79 m) and exposure (1.4 mg/m(3)) the estimated contribution to the annual change in FEV1 associated with dust was 10.4 mL/year. The annual change in FEV1/height(2) in current, compared with non-smokers was -1.9 (-7.2 to 3.4) (mL/m(2))×year(-1). The estimated overall annual decline in FEV1 among current and non-smokers in the highest exposed group was -91.2 (-124.3 to -58.1) (mL/m(2))×year(-1) and -49.0 (-80.2 to -17.8) (mL/m(2))×year(-1), respectively. CONCLUSIONS: Dust exposure, expressed by a quantitative JEM, was found to be associated with an increased yearly decline in FEV1 in employees of Norwegian SiC plants.


Assuntos
Compostos Inorgânicos de Carbono/efeitos adversos , Pneumopatias/induzido quimicamente , Pulmão/efeitos dos fármacos , Doenças Profissionais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Material Particulado/efeitos adversos , Compostos de Silício/efeitos adversos , Silício/efeitos adversos , Adulto , Poeira , Feminino , Volume Expiratório Forçado , Humanos , Indústrias , Exposição por Inalação/efeitos adversos , Pulmão/fisiopatologia , Pneumopatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Noruega , Doenças Profissionais/fisiopatologia , Exposição Ocupacional/análise , Material Particulado/química , Fumar , Espirometria , Inquéritos e Questionários
5.
Ann Occup Hyg ; 57(4): 417-31, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23204512

RESUMO

INTRODUCTION: The aim of this study was to identify important determinants of dust exposure in the Norwegian silicon carbide (SiC) industry and to suggest possible control measures. METHODS: Exposure to total dust, respirable dust, quartz, cristobalite, SiC, and fiber was assessed in three Norwegian SiC plants together with information on potential determinants of exposure. Mixed-effect models were constructed with natural log-transformed exposure as the dependent variable. RESULTS: The exposure assessment resulted in about 700 measurements of each of the sampled agents. Geometric mean (GM) exposure for total dust, respirable dust, fibers, and SiC for all workers was 1.6mg m(-3) [geometric standard deviation (GSD) = 3.2], 0.30mg m(-3) (GSD = 2.5), 0.033 fibers cm(-3) (GSD = 5.2), and 0.069mg m(-3) (GSD = 3.1), respectively. Due to a large portion of quartz and cristobalite measurements below the limit of detection in the processing and maintenance departments (>58%), GM for all workers was not calculated. Work in the furnace department was associated with the highest exposure to fibers, quartz, and cristobalite, while work in the processing department was associated with the highest total dust, respirable dust, and SiC exposure. Job group was a strong determinant of exposure for all agents, explaining 43-82% of the between-worker variance. Determinants associated with increased exposure in the furnace department were location of the sorting area inside the furnace hall, cleaning tasks, building and filling furnaces, and manual sorting. Filling and changing pallet boxes were important tasks related to increased exposure to total dust, respirable dust, and SiC in the processing department. For maintenance workers, increased exposure to fibers was associated with maintenance work in the furnace department and increased exposure to SiC was related to maintenance work in the processing department. CONCLUSION: Job group was a strong determinant of exposure for all agents. Several tasks were associated with increased exposure, indicating possibilities for exposure control measures. Recommendations for exposure reduction based on this study are (i) to separate the sorting area from the furnace hall, (ii) minimize manual work on furnaces and in the sorting process, (iii) use remote controlled sanders/grinders with ventilated cabins, (iv) use closed systems for filling pallet boxes, and (v) improve cleaning procedures by using methods that minimize dust generation.


Assuntos
Poluentes Ocupacionais do Ar/análise , Compostos Inorgânicos de Carbono/análise , Poeira/análise , Ocupações/classificação , Compostos de Silício/análise , Compostos Inorgânicos de Carbono/efeitos adversos , Monitoramento Ambiental/métodos , Humanos , Exposição por Inalação/análise , Exposição por Inalação/estatística & dados numéricos , Noruega/epidemiologia , Exposição Ocupacional/análise , Exposição Ocupacional/estatística & dados numéricos , Saúde Ocupacional/normas , Quartzo/efeitos adversos , Quartzo/análise , Compostos de Silício/efeitos adversos , Dióxido de Silício/efeitos adversos , Dióxido de Silício/análise
6.
Cardiovasc Revasc Med ; 13(6): 316-20, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23164477

RESUMO

BACKGROUND: The aim of this MULTIBENE study was to evaluate the safety and efficacy of the silicon carbide coated cobalt chromium PRO-Kinetik coronary stent system in patients with single de novo coronary lesions. METHODS AND MATERIALS: This prospective international multicenter study included 202 patients at 10 European sites. Analysis was performed on the per protocol population of 197 patients. Patients were followed until 12 months, a subset of patients (n=72) underwent additional coronary angiography at 6 months. Primary endpoint was 6-months rate of target vessel failure (TVF), defined as a composite of cardiac death, myocardial infarction and target vessel revascularization (TVR). RESULTS: At 6 months, rate of TVF was 10.9% and rate of major adverse cardiac events, a composite of cardiac death, MI, target lesion revascularization (TLR) and coronary artery bypass graft, was 11.4%, both being mainly attributed to TVR respective TLR. No cardiac death or stent thrombosis occurred. In-segment late lumen loss was 0.66±0.61mm and binary restenosis was 20.8%, as determined by core laboratory in the angiographic subgroup. CONCLUSION: Based on these data, the PRO-Kinetik coronary stent system was found to be safe and effective.


Assuntos
Cromo/uso terapêutico , Cobalto/uso terapêutico , Doença da Artéria Coronariana/terapia , Reestenose Coronária/terapia , Stents Farmacológicos/efeitos adversos , Adulto , Idoso , Compostos Inorgânicos de Carbono/efeitos adversos , Cromo/efeitos adversos , Cobalto/efeitos adversos , Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Intervenção Coronária Percutânea , Estudos Prospectivos , Compostos de Silício/efeitos adversos , Stents , Resultado do Tratamento
7.
Occup Environ Med ; 69(8): 527-33, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22611173

RESUMO

OBJECTIVES: An increased lung cancer risk associated with total dust exposure in the silicon carbide (SiC) industry has previously been reported. The aim of the present study was to examine the relative importance of specific exposure factors by using a comprehensive, historic job exposure matrix based on about 8000 measurements. METHODS: Cumulative exposure to total and respirable dust, respirable quartz, cristobalite, and SiC particles and SiC fibres was assessed for 1687 long-term workers employed during 1913-2003 in the Norwegian SiC industry. Standardised incidence ratios for lung cancer, with follow-up during 1953-2008, were calculated stratified by cumulative exposure categories. Poisson regression analyses were performed using both categorised and log-transformed cumulative exposure variables. RESULTS: The lung cancer incidence was about twofold increased at the highest level of exposure to each of the exposure factors (standardised incidence ratios 1.9-2.3 for all agents). Internal analyses showed associations between exposure level and lung cancer incidence for all investigated factors, but a significant trend only for total dust and cristobalite. In multivariate analyses, cristobalite showed the most consistent associations, followed by SiC fibres. CONCLUSIONS: The results indicated that crystalline silica in the form of cristobalite was the most important occupational exposure factor responsible for lung cancer excess in the Norwegian SiC industry. SiC fibres seemed to have an additional effect.


Assuntos
Compostos Inorgânicos de Carbono/efeitos adversos , Neoplasias Pulmonares/etiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Material Particulado/efeitos adversos , Compostos de Silício/efeitos adversos , Dióxido de Silício/efeitos adversos , Silício/efeitos adversos , Indústria Química , Poeira , Seguimentos , Humanos , Incidência , Neoplasias Pulmonares/epidemiologia , Masculino , Análise Multivariada , Noruega/epidemiologia , Doenças Profissionais/epidemiologia , Exposição Ocupacional/análise , Ocupações , Distribuição de Poisson
9.
PLoS One ; 6(2): e16487, 2011 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-21379573

RESUMO

BACKGROUND: Attachment strength of fouling organisms on silicone coatings is low. We hypothesized that low attachment strength on silicones is, in part, due to the interaction of surface available components with natural glues. Components could alter curing of glues through bulk changes or specifically through altered enzyme activity. METHODOLOGY/PRINCIPAL FINDINGS: GC-MS analysis of silicone coatings showed surface-available siloxanes when the coatings were gently rubbed with a cotton swab for 15 seconds or given a 30 second rinse with methanol. Mixtures of compounds were found on 2 commercial and 8 model silicone coatings. The hypothesis that silicone components alter glue curing enzymes was tested with curing barnacle glue and with commercial enzymes. In our model, barnacle glue curing involves trypsin-like serine protease(s), which activate enzymes and structural proteins, and a transglutaminase which cross-links glue proteins. Transglutaminase activity was significantly altered upon exposure of curing glue from individual barnacles to silicone eluates. Activity of purified trypsin and, to a greater extent, transglutaminase was significantly altered by relevant concentrations of silicone polymer constituents. CONCLUSIONS/SIGNIFICANCE: Surface-associated silicone compounds can disrupt glue curing and alter enzyme properties. Altered curing of natural glues has potential in fouling management.


Assuntos
Adesivos/metabolismo , Enzimas/metabolismo , Compostos de Silício/efeitos adversos , Thoracica/enzimologia , Thoracica/metabolismo , Adesividade/efeitos dos fármacos , Adesivos/química , Animais , Cimentação , Ativação Enzimática/efeitos dos fármacos , Ensaios Enzimáticos , Enzimas/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Fenômenos Mecânicos , Metanol/farmacologia , Modelos Biológicos , Modelos Teóricos , Compostos de Silício/química , Compostos de Silício/farmacologia , Propriedades de Superfície/efeitos dos fármacos , Thoracica/efeitos dos fármacos , Thoracica/fisiologia
10.
J Neurosci Methods ; 189(2): 216-29, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20399227

RESUMO

Brain implants provide exceptional tools to understand and restore cerebral functions. The utility of these devices depends crucially on their biocompatibility and long term viability. We addressed these points by implanting non-functional, NeuroProbes silicon probes, without or with hyaluronic acid (Hya), dextran (Dex), dexamethasone (DexM), Hya+DexM coating, into rat neocortex. Light and transmission electron microscopy were used to investigate neuronal survival and glial response. The surface of explanted probes was examined in the scanning electron microscope. We show that blood vessel disruption during implantation could induce considerable tissue damage. If, however, probes could be inserted without major bleeding, light microscopical evidence of damage to surrounding neocortical tissue was much reduced. At distances less than 100 microm from the probe track a considerable neuron loss ( approximately 40%) occurred at short survival times, while the neuronal numbers recovered close to control levels at longer survival. Slight gliosis was observed at both short and long term survivals. Electron microscopy showed neuronal cell bodies and synapses close (<10 microm) to the probe track when bleeding could be avoided. The explanted probes were usually partly covered by tissue residue containing cells with different morphology. Our data suggest that NeuroProbes silicon probes are highly biocompatible. If major blood vessel disruption can be avoided, the low neuronal cell loss and gliosis should provide good recording and stimulating results with future functional probes. We found that different bioactive molecule coatings had small differential effects on neural cell numbers and gliosis, with optimal results achieved using the DexM coated probes.


Assuntos
Materiais Biocompatíveis , Neocórtex , Neuroglia , Neurônios , Próteses e Implantes , Compostos de Silício , Animais , Materiais Biocompatíveis/efeitos adversos , Vasos Sanguíneos/patologia , Sobrevivência Celular , Dexametasona/efeitos adversos , Dextranos/efeitos adversos , Gliose/etiologia , Gliose/patologia , Ácido Hialurônico/efeitos adversos , Hemorragias Intracranianas/complicações , Hemorragias Intracranianas/patologia , Teste de Materiais , Neocórtex/citologia , Neocórtex/cirurgia , Neocórtex/ultraestrutura , Neuroglia/patologia , Neuroglia/fisiologia , Neuroglia/ultraestrutura , Neurônios/patologia , Neurônios/fisiologia , Neurônios/ultraestrutura , Próteses e Implantes/efeitos adversos , Ratos , Ratos Wistar , Compostos de Silício/efeitos adversos , Sinapses/ultraestrutura , Fatores de Tempo
11.
Scand J Work Environ Health ; 36(1): 71-79, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19953212

RESUMO

OBJECTIVES: A previous study among workers in the Norwegian silicon carbide industry, followed until 1996, revealed an excess incidence of lung and total cancer. The present study adds nine years of follow-up and focuses on cancer risk among short- and long-term workers, based on the assumption that these two groups have different exposure and lifestyle characteristics. METHODS: The total cohort for this study comprised 2612 men employed for >6 months between 1913 and 2003. The follow-up period for cancer was 1953-2005. Short-term workers were defined as having <3 years of total employment in the industry. We estimated standardized incidence ratios (SIR) using national rates as the expected values. RESULTS: Among the short-term workers, we observed an overall excess incidence of cancer [SIR 1.4, 95% confidence interval (95% CI) 1.2-1.6], with an excess of lung cancer (SIR 2.6, 95% CI 1.9-3.5) as the most important contributing factor. The long-term workers also had an excess incidence of total cancer (SIR 1.2, 95% CI 1.1-1.3) and lung cancer (SIR 1.7, 95% CI 1.3-2.2). We also observed an increased risk of cancers at other sites, specifically among short-term workers. CONCLUSIONS: We observed an increased risk of cancer (especially in the lung but also at other sites) among both short- and long-term workers. Dust exposure in the silicon carbide industry may have contributed to the increased risk among long-term workers, whereas the increased risk among short-term workers may be due to a combination of occupational and lifestyle factors.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Compostos Inorgânicos de Carbono/efeitos adversos , Neoplasias Pulmonares/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Compostos de Silício/efeitos adversos , Poeira , Indústrias Extrativas e de Processamento , Seguimentos , Humanos , Incidência , Neoplasias Pulmonares/etiologia , Noruega , Exposição Ocupacional/efeitos adversos
12.
J Mol Recognit ; 22(5): 380-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19585542

RESUMO

Brain machine interface (BMI) devices offer a platform that can be used to assist people with extreme disabilities, such as amyotrophic lateral sclerosis (ALS) and Parkinson's disease. Silicon (Si) has been the material of choice used for the manufacture of BMI devices due to its mechanical strength, its electrical properties and multiple fabrication techniques; however, chronically implanted BMI devices have usually failed within months of implantation due to biocompatibility issues and the fact that Si does not withstand the harsh environment of the body. Single crystal cubic silicon carbide (3C-SiC) and nanocrystalline diamond (NCD) are semiconductor materials that have previously shown good biocompatibility with skin and bone cells. Like Si, these materials have excellent physical characteristics, good electrical properties, but unlike Si, they are chemically inert. We have performed a study to evaluate the general biocompatibility levels of all of these materials through the use of in vitro techniques. H4 human neuroglioma and PC12 rat pheochromocytoma cell lines were used for the study, and polystyrene (PSt) and amorphous glass were used as controls or for morphological comparison. MTT [3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide] assays were performed to determine general cell viability with each substrate and atomic force microscopy (AFM) was used to quantify the general cell morphology on the substrate surface along with the substrate permissiveness to lamellipodia extension. 3C-SiC was the only substrate tested to have good viability and superior lamellipodia permissiveness with both cell lines, while NCD showed a good level of viability with the neural H4 line but a poor viability with the PC12 line and lower permissiveness than 3C-SiC. Explanations pertaining to the performance of each substrate with both cell lines are presented and discussed along with future work that must be performed to further evaluate specific cell reactions on these substrates.


Assuntos
Compostos Inorgânicos de Carbono/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/patologia , Diamante/farmacologia , Neurônios/efeitos dos fármacos , Compostos de Silício/farmacologia , Animais , Compostos Inorgânicos de Carbono/efeitos adversos , Linhagem Celular Tumoral , Diamante/efeitos adversos , Humanos , Microscopia de Força Atômica , Neurônios/patologia , Células PC12 , Ratos , Compostos de Silício/efeitos adversos
13.
Rev. senol. patol. mamar. (Ed. impr.) ; 22(3): 122-124, 2009. ilus
Artigo em Espanhol | IBECS | ID: ibc-74266

RESUMO

La silicona líquida está formada por polímeros de dimetilsiloxano.El uso de esta sustancia para el aumento de tejidosblandos como es la mamoplastia de aumento, puede ocasionarla aparición de granulomas, entre otros efectos indeseables.También dificulta posteriormente el diagnóstico tempranodel cáncer de mama. La técnica diagnóstica más aceptadaes la resonancia magnética. El tratamiento sintomático y etiológicode las complicaciones (eliminar la sustancia inyectada)presenta problemas difíciles de resolver. Presentamos dos casosde complicación aguda por reacción a cuerpo extraño trasinyección intramamaria de silicona líquida(AU)


Liquid silicone is derived from dimethylsiloxane polymers.The use of this substance to augment soft tissues as breastaugmentation is associated with the appearance of granulomas,among other undesirable effects. Its use also leads toenormous difficulty in the early diagnosis of breast cancer.Magnetic resonance has become the most accepted test fordiagnosis. The symptomatic and etiological treatment (removalof injected substance) presents problems that are difficult tosolve. We present two cases of foreign body reactions as anacute complication after intramammary injection of liquid silicone(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Mamoplastia/efeitos adversos , Mamoplastia/métodos , Compostos de Silício/efeitos adversos , Granuloma/complicações , Granuloma/etiologia , Granuloma , Mamografia/instrumentação , Mamografia/métodos , Ultrassonografia Mamária , Mastectomia/métodos , Diagnóstico Diferencial , Neoplasias da Mama/epidemiologia , Fatores Imunológicos/uso terapêutico
14.
Cir. plást. ibero-latinoam ; 34(1): 1-10, ene.-mar. 2008. ilus
Artigo em Es | IBECS | ID: ibc-64973

RESUMO

La necesidad de rellenar arrugas y otras depresiones en la piel ha llevado a la creación de múltiples sustancias inyectables. Los desastrosos resultados producidos por varias de estas sustancias meses o años después de ser inyectados, llevaron al autor a crear el término “Alogenosis Iatrogénica”, pues se trata de una nueva enfermedad que sólo en Ibero Latinoamérica tiene más de un millón de víctimas: “Alogenosis”, porque es producida por sustancias alógenas, es decir, ajenas al organismo e “Iatrogénica”, porque la producen los médicos o las personas que inyectan estas sustancias. Hemos estudiado 358 casos en los últimos 10 años, agrupados y catalogados según las sustancias inyectadas, los síntomas, signos, tiempo de aparición de los mismos, etc. El objetivo era aprender cómo se manejan y tratan sus complicaciones. ya que en ningún libro se encuentra claramente descrita la nueva enfermedad. Las sustancias inyectables de relleno más usadas fueron: silicona líquida, parafina, petrolato líquido, vaselina, “biopolímeros”, aceite mineral, grasa animal, etc. No se incluyeron en el estudio otras sustancias más o menos aceptadas como rellenos biocompatibles (ácido hialurónico, grasa autógena, colágeno bovino tratado, hidroxiapatita, etc.).Las reacciones, que afortunadamente no se presentan en todos los pacientes, aparecieron entre las 6 horas y los 25 años del tratamiento y fueron locales (dolor, eritema, pigmentaciones, edemas, fibrosis, queloides, infecciones, fístulas, necrosis de piel, desplazamiento por gravedad, etc.) y generales (fiebre, dolor generalizado, artralgias, decaimiento, malestar general, aumento de caída del cabello, depresión, etc.). No se encontró relación con enfermedades autoinmunes tales como artritis, dermatomiositis, esclerodermia, etc. Los síntomas y signos se exacerban cada dos o tres meses durante períodos que duran de 1 a 3 semanas y mejoran con o sin tratamiento. El tratamiento es sintomático. Las resecciones quirúrgicas solo deben hacerse en zonas muy limitadas, pues producen depresiones cutáneas y cicatrices retráctiles. Las masas muy grandes no se deben resecar debido a las deformaciones consecuentes. Se debe proteger la piel con sustancias emolientes. El aspecto más importante de este estudio es lo que no debe hacerse: los corticoides locales o generales no sirven y aumentan la atrofia de la piel; las punciones y la liposucción no ayudan, pues las masas son sólidas y fibróticas; los masajes, el ultrasonido y el láser no ayudan y a veces empeoran la situación. En todos los países se deben realizar campañas oficiales de prevención contra estas sustancias (AU)


The need to replenish wrinkles and depressions has enticed the creation of multiplesolid or semi-solid injectable substances. The disastrous results of some of thesehave led me to create the term “Iatrogenic Allogenosis”: “Allogenosis”, because it isproduced by allogenic (foreign) substances. “Iatrogenic”, because we, the physiciansor persons injecting these substances, have caused this disease. Over one million personsin Latin-America have become victims of these substances. Our objective is tolearn how to treat these cases.We have studied 358 cases in a 10-year time span. We have grouped them andtried to reach conclusions. Mostly used substances are: liquid silicon, paraffin, liquidpetrolatum, Vaseline, mineral oil, animal fat, etc. We have not included in thisstudy some substances that have been fairly accepted by surgeons: autogenous fat,bovine collagen, hydroxyapatite, acrylic, hyaluronic acid, etc.Reactions are local and general. The latency period varies from 6 hours to 25years. Local reactions are: pain, erhytema, edema, pigmentations, swelling, fibrosis,keloids, infection, fistulas, necrosis, gravity displacement, etc. The general ones are:fever, arthralgia, general discomfort, we have no find relations with autoimmune diseases(dermatomyositis, scleroderma, etc.).Treatment is symptomatic. Surgical resection has to be very limited because itleaves very notorious scars and retractions. Large masses must not be operated.Liposuction is not effective. Corticoids an massages make the situation even worst.It does not dissolve the masses and does atrophy the normal skin covering them, andthus, underlying masses are more noticeable. Exacerbation may occur every 3 or 4months and will cure wit or without an anti-inflammatory or an antibiotic. An intensepreventive campaign must be launched (AU)


Assuntos
Humanos , Masculino , Feminino , Doença Iatrogênica/epidemiologia , Doenças do Colágeno/complicações , Doenças do Colágeno/diagnóstico , Colágeno/efeitos adversos , Dor/complicações , Eritema/complicações , Biopolímeros/efeitos adversos , Dermatomiosite/complicações , Esclerodermia Localizada/complicações , Autoimagem , Doença Iatrogênica/prevenção & controle , Dermatomiosite/diagnóstico , Compostos de Silício/efeitos adversos , Parafina/efeitos adversos , Óleo Mineral/efeitos adversos , Qualidade de Vida/psicologia , Valor da Vida
15.
Neurotoxicology ; 28(5): 1032-42, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17420053

RESUMO

Silicofluorides (SiFs), fluosilicic acid (FSA) and sodium fluosilicate (NaFSA), are used to fluoridate over 90% of US fluoridated municipal water supplies. Living in communities with silicofluoride treated water (SiFW) is associated with two neurotoxic effects: (1) Prevalence of children with elevated blood lead (PbB>10microg/dL) is about double that in non-fluoridated communities (Risk Ratio 2, chi2p<0.01). SiFW is associated with serious corrosion of lead-bearing brass plumbing, producing elevated water lead (PbW) at the faucet. New data refute the long-prevailing belief that PbW contributes little to children's blood lead (PbB), it is likely to contribute 50% or more. (2) SiFW has been shown to interfere with cholinergic function. Unlike the fully ionized state of fluoride (F-) in water treated with sodium fluoride (NaFW), the SiF anion, [SiF6]2- in SiFW releases F- in a complicated dissociation process. Small amounts of incompletely dissociated [SiF6]2- or low molecular weight (LMW) silicic acid (SA) oligomers may remain in SiFW. A German PhD study found that SiFW is a more powerful inhibitor of acetylcholinesterase (AChE) than NaFW. It is proposed here that SiFW induces protein mis-folding via a mechanism that would affect polypeptides in general, and explain dental fluorosis, a tooth enamel defect that is not merely "cosmetic" but a "canary in the mine" foretelling other adverse, albeit subtle, health and behavioral effects. Efforts to refute evidence of such effects are analyzed and rebutted. In 1999 and 2000, senior EPA personnel admitted they knew of no health effects studies of SiFs. In 2002 SiFs were nominated for NTP animal testing. In 2006 an NRC Fluoride Study Committee recommended such studies. It is not known at this writing whether any had begun.


Assuntos
Desinfetantes/química , Desinfecção , Fluoretação/efeitos adversos , Fluoretos/efeitos adversos , Fluoretos/química , Intoxicação por Chumbo/epidemiologia , Chumbo/sangue , Compostos de Silício/efeitos adversos , Compostos de Silício/química , Abastecimento de Água/análise , Corrosão , Cárie Dentária/epidemiologia , Humanos , Massachusetts/epidemiologia , Engenharia Sanitária
16.
Cir. Esp. (Ed. impr.) ; 80(4): 227-229, oct. 2006. ilus
Artigo em Es | IBECS | ID: ibc-048966

RESUMO

La utilización de silicona líquida con el fin de aumentar el volumen mamario tuvo una amplia difusión en la década de los años sesenta del siglo pasado, pero a finales de ésta, tras la publicación de numerosos estudios que describían la aparición de un gran número de complicaciones locales, así como la migración a distancia de pequeñas cantidades de silicona, su práctica se abandonó. Su empleo dificulta posteriormente el diagnóstico temprano del cáncer de mama, por lo que este grupo de pacientes no debe incluirse en los programas habituales de cribado, sino que han de seguir controles periódicos y exhaustivos. En este contexto, la resonancia magnética es la mejor prueba de imagen para la detección temprana de procesos malignos mamarios. La presencia de complicaciones locales, la sospecha de una lesión maligna o el deseo de la paciente por evitar ambas situaciones son indicación de la mastectomía subcutánea (AU)


The use of liquid silicone for breast augmentation was widespread in the 1960s but was abandoned at the end of the decade due to numerous studies describing the development of a large number of local complications, as well as remote migration of small amounts of silicone. The use of liquid silicone also leads to enormous difficulty in the early diagnosis of breast cancer; these patients are precluded from routine screening programs and must undergo exhaustive periodic examinations. Magnetic resonance imaging has become the most effective test for the early detection of breast cancer in these patients. Indications for subcutaneous mastectomy are the presence of local complications, suspicion of a malignant lesion, or the patient's desire to prevent both these potential problems (AU)


Assuntos
Feminino , Adulto , Humanos , Compostos de Silício/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Mastectomia/métodos , Mamografia/métodos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/diagnóstico , Mastite/complicações , Mastite/diagnóstico , Granuloma/complicações , Granuloma/diagnóstico , Dor/complicações , Dor/diagnóstico , Dor/etiologia
17.
J Neurosci Methods ; 155(2): 285-90, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16513179

RESUMO

Improving models of human stroke by the use of aged animals has been advocated; however the commonly used rat middle cerebral artery thread-occlusion model has produced suboptimal stroke induction and excess mortality in aged rats. We report the development of a modified method for silicone-coating the tip of occluding threads which produces a malleable silicone-coated tip which is firmly bonded and of highly consistent diameter, and overcomes problems of thread insertion through the narrowed carotid canal found in aged animals. Comparison of stroke outcomes and mortality were made between these threads and heat-treated poly-L-lysine coated threads. The rate of successful stroke induction in aged rats was significantly improved (from 14% to 86%). Similarly, mortality fell from 21-31% to 3-7% or less in both young and old rats with or without diabetes and hypertension. An occluding thread tip diameter of 0.35-0.38 mm was optimal for induction of mid-sized strokes in both young and old rats. This method of thread manufacture overcomes problems of inconsistency of diameter and bonding of the silicone-coated tip, and these threads produce significant improvements in stroke induction by MCA occlusion, particularly in aged animals and those with co-morbidities.


Assuntos
Envelhecimento/fisiologia , Constrição Patológica/complicações , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/etiologia , Infarto da Artéria Cerebral Média/mortalidade , Animais , Infarto Encefálico/patologia , Circulação Cerebrovascular/fisiologia , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Fluxometria por Laser-Doppler/métodos , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional/fisiologia , Compostos de Silício/efeitos adversos , Sais de Tetrazólio
19.
Actas dermo-sifiliogr. (Ed. impr.) ; 96(9): 598-601, nov. 2005. ilus
Artigo em Es | IBECS | ID: ibc-041780

RESUMO

En los últimos años, ha aumentado la demanda de intervenciones estéticas de relleno de partes blandas mediante inyección de diversas sustancias, dada su aparente inocuidad. Sin embargo, estos procedimientos no están exentos de reacciones adversas, como la formación de granulomas de cuerpo extraño, fenómeno descrito en la literatura médica con la mayoría de los materiales utilizados. Comunicamos el caso de una paciente con lesiones inflamatorias en la cara cuyo diagnóstico se efectuó tras el estudio histopatológico y que permitió la observación de un granuloma por silicona líquida


In recent years, the demand for cosmetic interventions to augment soft tissue by injecting different substances has increased, due to their apparent innocuity. However, these procedures are not free from adverse reactions, such as the formation of foreign body granulomas, a phenomenon described in literature with most of the materials used. We report the case of a female patient with inflammatory lesions of the face, whose diagnosis was made after the histopathological study, which revealed a granuloma caused by liquid silicone


Assuntos
Feminino , Pessoa de Meia-Idade , Humanos , Granuloma/diagnóstico , Granuloma/terapia , Compostos de Silício/uso terapêutico , Compostos de Silício/efeitos adversos , Dor Facial/diagnóstico , Radiografia Panorâmica/métodos , Corticosteroides/uso terapêutico , Diagnóstico Diferencial , Imunossupressores/uso terapêutico , Eritema Endurado/diagnóstico , Leucocitose/complicações , Leucocitose/diagnóstico , Eritema Endurado/complicações , Dor Facial/etiologia , Tomografia Computadorizada de Emissão/métodos , Prednisona/uso terapêutico , Ciclosporina/uso terapêutico , Isotretinoína/uso terapêutico , Minociclina/uso terapêutico , Eritema/complicações
20.
Eur J Pediatr ; 163(4-5): 239-40, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14767764

RESUMO

UNLABELLED: Nephrocalcinosis and/or urinary calculi are rare in infants. Furosemide treatment during the neonatal period, vitamin D intoxication, hereditary diseases such as hyperoxaluria or distal tubular acidosis are among the most common aetiologies. We report the case of a 6-month-old boy with an extra-hepatic biliary duct atresia treated by the Kasai procedure and a gastro-oesophageal reflux treated with a silicate containing milk thickener (Gelopectose, 5.5% colloidal silicate) since the neonatal period. He did not present any other endogenous risk factor for urinary stone formation (normal urinary calcium/creatinine ratio; normal urinary magnesium excretion). The nephrolithiasis was discovered as the boy presented painful episodes of macroscopic haematuria. Ultrasound examination revealed bilateral nephrocalcinosis and multiple bilateral calculi without infection or urinary obstruction. Infrared spectroscopy revealed silicate as the major component suggesting silicate absorption to be responsible for the described symptoms. After replacement of the silicate-containing agent by a silicate-free milk thickener, the lesions were completely reversible as confirmed by repeated renal ultrasound examinations over a 2-month period. CONCLUSION: Silicate-containing milk thickeners can be responsible for urinary calculi and/or nephrocalcinosis.


Assuntos
Pectinas/efeitos adversos , Compostos de Silício/efeitos adversos , Cálculos Urinários/induzido quimicamente , Refluxo Gastroesofágico/tratamento farmacológico , Hematúria/induzido quimicamente , Humanos , Lactente , Rim/diagnóstico por imagem , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Pectinas/uso terapêutico , Compostos de Silício/uso terapêutico , Ultrassonografia
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