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1.
Acta Cytol ; 63(1): 35-43, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30352442

RESUMO

OBJECTIVES: To validate the ecological modification of the Papanicolaou stain (Eco-Pap) for the diagnosis of cervical cancer. STUDY DESIGN: A prospective study was performed at the Mother and Child "San Bartolomé" Hospital, Lima, Peru. Reagent handling strategies were divided into three phases: we used (1) Harris progressive hematoxylin (for nuclear staining), (2) a polychromatic solution (a mix of EA-36/Orange G-6 to suppress the use of several alcohol baths), and (3) direct mounting (with Entellan® solution). The cellular details were analyzed by the staining quality index, an external quality control, and the Bethesda System 2014. RESULTS: We evaluated 72,901 cervical smears stained with the Eco-Pap. The validation of the Eco-Pap against the conventional Pap stain was optimal (κ = 0.89; 95% CI: 0.87-0.92), showing a sensibility and specificity of 88.3% (95% CI: 85.1-90.0) and 98.7% (95% CI: 98-99.2), respectively. The Eco-Pap dramatically reduced the environmental pollution caused by 72 L of xylene, hydrochloric acid, and ammonia (6 L each) and mercury oxide. CONCLUSION: The Eco-Pap is an innovative and efficient staining method reducing the use of toxic reagents with carcinogenic potential during cervical cancer screening by exfoliative cytology.


Assuntos
Poluentes Ambientais/efeitos adversos , Poluição Ambiental/prevenção & controle , Eliminação de Resíduos de Serviços de Saúde , Teste de Papanicolaou/métodos , Coloração e Rotulagem/métodos , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal , Amônia/efeitos adversos , Compostos Azo/química , Corantes/química , Estudos Transversais , Poluição Ambiental/efeitos adversos , Feminino , Hematoxilina/química , Humanos , Ácido Clorídrico/efeitos adversos , Compostos de Mercúrio/efeitos adversos , Óxidos/efeitos adversos , Teste de Papanicolaou/efeitos adversos , Peru , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Xilenos/efeitos adversos
2.
Ci. Rural ; 46(2): 279-285, 2016.
Artigo em Inglês | VETINDEX | ID: vti-13928

RESUMO

The mineral nutritional homeostasis in response to different concentrations of Hg (0, 25 and 50;M) was evaluated in Pfaffia glomerata plant. The exposure to the highest level of Hg (50µM) caused a decreasing in shoot and root fresh weights of 15.5% and 20%, respectively. Both shoot and root Hg concentrations increased linearly with increasing external Hg concentrations. Ca concentration decreased in shoot only at 50µM Hg, whereas shoot K and Mg concentrations decreased at both 25 and 50µM Hg, when compared to the control. A significant decrease in Cu, Zn, Fe and Mn concentrations in plants exposed to Hg was observed, but most Zn, Mn, and Cu in the roots. On the other hand, P concentration increased in both root and shoot of plants exposed at 25 and 50µM Hg, whereas Na concentration increased only in the root at 25 and 50µM Hg exposure. In general, tissue nutrient concentrations in P. glomerata plantlets exposed to Hg were significantly decreased, which indicates that the Hg may cause alteration on the mineral nutritional homeostasis of this species.(AU)


A homeostase nutricional mineral em resposta a diferentes concentrações de Hg (0, 25 e 50;M) foram avaliadas em plantas de Pfaffia glomerata. A exposição ao mais alto nível de Hg (50µM) causou um decréscimo de 15,5% e 20%, respectivamente, na matéria fresca da parte aérea e raízes. As concentrações de Hg na parte aérea e raízes aumentaram linearmente com o aumento das concentrações de Hg. A concentração de Ca decresceu na parte aérea somente em 50µM Hg, enquanto as concentrações de K e Mg na parte aérea decresceram tanto em 25 como em 50µM Hg, quando comparado ao controle. Observou-se um significativo decréscimo nas concentrações de Cu, Zn, Fe e Mn nas plantas expostas ao Hg, mas principalmente Zn, Mn e Cu nas raízes. Por outro lado, a concentração de P aumentou em raízes e parte aérea de plantas expostas a 25 e 50µM Hg, enquanto a concentração de Na aumentou somente nas raízes em 25 e 50µM Hg. No geral, as concentrações de nutrientes nos tecidos de P. glomerata expostas ao Hg foram significativamente diminuídas, o que indica que o Hg pode causar alterações na homeostase nutricional mineral dessa espécie.(AU)


Assuntos
Compostos de Mercúrio/efeitos adversos , Panax , Homeostase , Nutrientes , Micronutrientes
3.
Psychol. neurosci. (Impr.) ; 6(1): 123-127, Jan.-June 2013. ilus
Artigo em Inglês | LILACS | ID: lil-687861

RESUMO

Methylmercury (MeHg) is present in the environment because of natural and anthropogenic causes. MeHg can reach the central nervous system (CNS) and cause neurological damage in humans and animals. Electric organ discharges (EODs) in the weak electric fish Gymnotus sylvius are produced by the electric organ and modulated by the CNS. These discharges are used for electrolocation and communication. The purpose of the present study was to investigate the effects of dietary MeHg exposure on EOD rate in G. sylvius. An oscilloscope was used to record the EOD rate. Two treatments were investigated: chronic MeHg administration (4 µg/kg MeHg every 2 days, with a total of nine dietary exposures to MeHg) and acute MeHg administration (a single dose of 20 µg/kg MeHg). The control data for both treatments were collected every 2 days for 18 days, with a total of nine sessions (day 1 until day 18). Data of fish exposed to MeHg were collected every 2 days, totaling nine sessions (day 19 until day 36). Chronic treatment significantly increased the EOD rate in G. sylvius (p < .05), especially with the final treatment (day 32 until day 36). Acute treatment resulted in an initial increase in the EOD rate, which was maintained midway through the experiment (day 26 until day 30; p < .05). The present study provides the first insights into the effects of MeHg on EODs in weak electric fish. The EOD rate is a novel response of the fish to MeHg administration.


Assuntos
Animais , Comportamento Animal , Compostos de Mercúrio/efeitos adversos , Compostos de Mercúrio/efeitos da radiação , Peixe Elétrico
4.
Psychol. neurosci. (Impr.) ; 6(1): 123-127, Jan.-June 2013. ilus
Artigo em Inglês | Index Psicologia - Periódicos | ID: psi-59520

RESUMO

Methylmercury (MeHg) is present in the environment because of natural and anthropogenic causes. MeHg can reach the central nervous system (CNS) and cause neurological damage in humans and animals. Electric organ discharges (EODs) in the weak electric fish Gymnotus sylvius are produced by the electric organ and modulated by the CNS. These discharges are used for electrolocation and communication. The purpose of the present study was to investigate the effects of dietary MeHg exposure on EOD rate in G. sylvius. An oscilloscope was used to record the EOD rate. Two treatments were investigated: chronic MeHg administration (4 µg/kg MeHg every 2 days, with a total of nine dietary exposures to MeHg) and acute MeHg administration (a single dose of 20 µg/kg MeHg). The control data for both treatments were collected every 2 days for 18 days, with a total of nine sessions (day 1 until day 18). Data of fish exposed to MeHg were collected every 2 days, totaling nine sessions (day 19 until day 36). Chronic treatment significantly increased the EOD rate in G. sylvius (p < .05), especially with the final treatment (day 32 until day 36). Acute treatment resulted in an initial increase in the EOD rate, which was maintained midway through the experiment (day 26 until day 30; p < .05). The present study provides the first insights into the effects of MeHg on EODs in weak electric fish. The EOD rate is a novel response of the fish to MeHg administration.(AU)


Assuntos
Animais , Peixe Elétrico , Compostos de Mercúrio/efeitos adversos , Compostos de Mercúrio/efeitos da radiação , Comportamento Animal
5.
Neurotoxicology ; 37: 173-81, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23680050

RESUMO

BACKGROUND: Visual functions are known to be sensitive to toxins such as mercury (Hg) and lead (Pb), while omega-3 fatty acids (FA) and selenium (Se) may be protective. In the Tapajós region of the Brazilian Amazon, all of these elements are present in the local diet. OBJECTIVE: Examine how near visual contrast sensitivity and acquired color vision loss vary with biomarkers of toxic exposures (Hg and Pb) and the nutrients Se and omega-3 FA in riverside communities of the Tapajós. METHODS: Complete visuo-ocular examinations were performed. Near visual contrast sensitivity and color vision were assessed in 228 participants (≥15 years) without diagnosed age-related cataracts or ocular pathologies and with near visual acuity refracted to at least 20/40. Biomarkers of Hg (hair), Pb (blood), Se (plasma), and the omega-3 FAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in plasma phospholipids were measured. Multiple linear regressions were used to examine the relations between visual outcomes and biomarkers, taking into account age, sex, drinking and smoking. RESULTS: Reduced contrast sensitivity at all spatial frequencies was associated with hair Hg, while %EPA, and to a lesser extent %EPA+DHA, were associated with better visual function. The intermediate spatial frequency of contrast sensitivity (12 cycles/degree) was negatively related to blood Pb and positively associated with plasma Se. Acquired color vision loss increased with hair Hg and decreased with plasma Se and %EPA. CONCLUSIONS: These findings suggest that the local diet of riverside communities of the Amazon contain toxic substances that can have deleterious effects on vision as well as nutrients that are beneficial for visual function. Since remediation at the source is a long process, a better knowledge of the nutrient content and health effects of traditional foods would be useful to minimize harmful effects of Hg and Pb exposure.


Assuntos
Visão de Cores , Sensibilidades de Contraste , Dieta , Contaminação de Alimentos , Alimentos Marinhos , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Brasil , Defeitos da Visão Cromática/etiologia , Defeitos da Visão Cromática/prevenção & controle , Estudos Transversais , Dieta/efeitos adversos , Ácidos Graxos Ômega-3/sangue , Feminino , Cabelo/química , Humanos , Chumbo/efeitos adversos , Chumbo/sangue , Modelos Lineares , Masculino , Compostos de Mercúrio/efeitos adversos , Compostos de Mercúrio/análise , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Alimentos Marinhos/efeitos adversos , Alimentos Marinhos/análise , Selênio/sangue , Testes Visuais , Adulto Jovem
6.
Sci Total Environ ; 416: 513-26, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22200375

RESUMO

Low-rank, high-mineral matter Bulgarian coals were studied using a variety of chemical, optical, and electron beam methods. The larger fly ash carbon phases include charred carbons in contrast to coked carbons present in the fly ashes of bituminous-coal-derived fly ashes. Nanoscale carbons include multi-walled carbon nanotubes (MWCNTs) encapsulating Hg, Se, and As, among other elements. In addition to the glass which dominates the fly ash, relatively coarse 'rock fragments', consisting of an unmelted to partially melted core surrounded by a glassy rim, are present in the fly ash. Nano-scale minerals can contain hazardous elements and, along with metal-bearing multiwalled nanotubes, can be a path for the entry of hazardous particles into the lungs and other organs.


Assuntos
Cinza de Carvão/efeitos adversos , Exposição Ambiental/efeitos adversos , Nanopartículas/efeitos adversos , Material Particulado/efeitos adversos , Arsenicais/efeitos adversos , Arsenicais/análise , Bulgária , Cinza de Carvão/química , Exposição Ambiental/análise , Humanos , Compostos de Mercúrio/efeitos adversos , Compostos de Mercúrio/análise , Nanopartículas/química , Material Particulado/análise , Medição de Risco , Compostos de Selênio/efeitos adversos , Compostos de Selênio/análise
7.
J Pediatr ; 157(1): 127-31, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20338578

RESUMO

OBJECTIVE: To study hair mercury concentrations among women of reproductive age in relation to fish intake in Ontario, Canada. STUDY DESIGN: Three groups were studied: 22 women who had called the Motherisk Program for information on the reproductive safety of consuming fish during pregnancy, a group of Japanese residing in Toronto (n=23) consuming much larger amounts of fish, and a group of Canadian women of reproductive age (n=20) not seeking advice, were studied. Mercury concentrations in hair samples were measured using inductively coupled plasma mass spectrometry. Seafood consumption habits were recorded for each participant. Based on the types of fish consumed and consumption frequencies, the estimated monthly intake of mercury was calculated. Hair mercury concentrations were correlated to both the number of monthly seafood servings and the estimated ingested mercury dose. RESULTS: There were significant correlations between fish servings and hair mercury (Spearman r=0.73, P<.0001) and between amounts of consumed mercury and hair mercury concentrations (Spearman r=0.81, P<.0001). Nearly two thirds of the Motherisk callers, all of the Japanese women, and 15% of the Canadian women of reproductive age had hair mercury above 0.3 microg/g, which was shown recently to be the lowest observable adverse effect level in a large systematic review of all perinatal studies. CONCLUSIONS: Because of very wide variability, general recommendations for a safe number of fish servings may not be sufficient to protect the fetus. Analysis of hair mercury may be warranted before pregnancy in selected groups of women consuming more than 12 ounces of fish per week, as dietary modification can decrease body burden and ensure fetal safety.


Assuntos
Comportamento Alimentar , Desenvolvimento Fetal , Peixes , Cabelo/química , Mercúrio/análise , Segurança , Adulto , Animais , Povo Asiático , Canadá , Feminino , Humanos , Espectrometria de Massas , Compostos de Mercúrio/administração & dosagem , Compostos de Mercúrio/efeitos adversos , Ontário , Gravidez , Análise de Regressão , Alimentos Marinhos , Poluentes Químicos da Água/análise
8.
Sci Total Environ ; 408(4): 806-11, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19914681

RESUMO

This study was designed to assess possible associations between biomarkers of mercury (Hg) exposure and oxidative stress in fish-eating Amazonian communities. Clinical samples were obtained from riparians living in the Brazilian Amazon. Biomarkers of oxidative stress (glutathione - GSH, glutathione peroxidase - GSH-Px, catalase - CAT, activity and reactivation index of delta-aminolevulinate dehydratase - ALA-D (R%) were determined in blood. Total Hg was measured in whole blood (B-Hg), plasma (P-Hg) and hair (H-Hg). Association between biomarkers of Hg exposure and oxidative stress were examined using multiple regression models, including age, gender, alcohol consumption, smoking status, fish consumption and then stratified for gender. Significant inverse relations were observed between GSH-Px, GSH, CAT, ALA-D activity and B-Hg or H-Hg (p<0.05). ALA-D reactivation index was positively related to B-Hg (p<0.0001). P-Hg was directly related to ALA-D reactivation index and inversely associated with GSH-Px, GSH, and ALA-D activity (p<0.05). When stratified for gender, women showed significant inverse associations between all biomarkers of Hg exposure and CAT (p<0.05) or GSH (p<0.05), while for men only P-Hg showed a significant inverse relation with GSH (p<0.001). Our results clearly demonstrated an association between Hg exposure and oxidative stress. Moreover, for B-Hg, P-Hg and H-Hg gender differences were present.


Assuntos
Exposição Ambiental/efeitos adversos , Poluentes Ambientais/efeitos adversos , Compostos de Mercúrio/efeitos adversos , Intoxicação por Mercúrio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores/sangue , Brasil , Estudos Transversais , Monitoramento Ambiental , Poluentes Ambientais/sangue , Feminino , Peixes , Contaminação de Alimentos/análise , Cabelo/química , Humanos , Masculino , Compostos de Mercúrio/sangue , Pessoa de Meia-Idade , Oxirredutases/sangue , Rios , Adulto Jovem
10.
Environ Res ; 84(3): 197-203, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11097792

RESUMO

Fish consumption is an important source of protein among indigenous communities in Amazonian Brazil. Exposures to mercury via fish were studied in an indigenous community of the Munduruku reserve, located in the Tapajós River basin in the state of Pará, one of the oldest and most productive gold mining areas in the Amazon region. This study summarizes the results of mercury (Hg) analyses of fish consumed by inhabitants of the Munduruku settlement of Sai Cinza. The most frequently consumed fish, reported by 330 persons interviewed for this study, were tucunaré, pacu, jaraqui, traíra, aracu, matrinchã, and caratinga. The mean mercury concentration in carnivorous fish was 0.297 microg.g(-1) while in noncarnivorous fish mean mercury concentration was 0.095 microg.g(-1). Only in caratinga was there a significant relationship between fish size, weight, and mercury levels. Levels of methylmercury in the tucunaré averaged 0.170 microg.g(-1), while in traíra the mean level of methylmercury was 0.212 microg.g(-1). Although the levels of Hg in fish consumed by the Sai Cinza community are below the Brazilian limit value for consumption, the high rates and amounts of fish consumed by this population are relevant to evaluating risks of mercury contamination for communities with limited food resources.


Assuntos
Exposição Ambiental , Peixes , Contaminação de Alimentos , Compostos de Mercúrio/análise , Compostos de Metilmercúrio/análise , Poluição Química da Água/análise , Animais , Brasil , Dieta , Humanos , Indígenas Sul-Americanos , Compostos de Mercúrio/efeitos adversos , Compostos de Metilmercúrio/efeitos adversos , Saúde Pública
11.
Environ Res ; 84(3): 204-10, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11097793

RESUMO

The region of Alta Floresta in the South of the Amazon basin, close to the Teles Pires River, was one of the main prospecting gold areas in the Amazon Basin until the beginning of the 1990s. The economic growth was accompanied by a considerable increase in the population, due to a massive influx of migrants from the southern region of the country. Women had an important role during that process. They worked in the "garimpos" in different activities, such as cooking or managing, where they were exposed mainly to indoor elemental mercury during burning of amalgam. They also worked in gold dealers' shops, where a great amount of amalgam was burned daily. Fish consumption was an important dietary protein source and also a possible exposure pathway, due to the high Hg concentrations reported in carnivorous species. The present study evaluates the mercury uptake and consequent risks involved for pregnant women from Alta Floresta at the end of the gold rush period. The survey included women at different pregnancy stages and it was supported by clinical exams, followed by an interview with a specific questionnaire. Mercury hair concentrations ranging from 0.05 to 8.2 microg/g were found among women, with 13% of them showing concentrations above 2 microg/g. According to the results, mean differences in hair mercury concentration were statistically higher for pregnant women if they had worked in gold mining areas, they had consumed alcohol, their husbands had worked as "garimpeiros," they ate fish, and/or they had malaria before and/or during pregnancy


Assuntos
Exposição Ambiental/análise , Contaminação de Alimentos , Compostos de Mercúrio/análise , Poluentes Químicos da Água/análise , Adolescente , Adulto , Consumo de Bebidas Alcoólicas , Brasil/epidemiologia , Anormalidades Congênitas/epidemiologia , Dieta , Feminino , Cabelo/química , Humanos , Incidência , Compostos de Mercúrio/efeitos adversos , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez/metabolismo , Saúde Pública , Fatores de Risco , Poluentes Químicos da Água/efeitos adversos
12.
Environ Res ; 84(2): 100-7, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11068923

RESUMO

Cross-sectional studies were conducted in three riverside communities in the state of Pará in the Amazon Region of Brazil. Two of these communities, Brasília Legal and São Luís do Tapajós, are located in a watershed exposed to mercury pollution from artisanal gold mining, and the third, Santana do Ituqui, is outside this area. The studies were based upon a community census and included all persons volunteering for participation in each community. All participants were surveyed by questionnaire for health history, occupation, residence, and diet. Clinical evaluations were also done on each subject, along with collection of blood, urine, feces, and hair. Fish samples were collected to represent the most frequently consumed species. Mercury was measured in hair and fish. Although no signs or symptoms of overt mercury intoxication were observed, persons in Brasília Legal and São Luís do Tapajós had higher levels of mercury in hair than residents of Santana de Ituqui, located out of the risk area. Levels of mercury in fish were below Brazilian health guidance limits, but the high rates of fish consumption among these populations raise concerns for the possible effects of chronic exposure, especially among young children and women of childbearing age.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Compostos de Mercúrio/efeitos adversos , Poluição Química da Água/efeitos adversos , Poluição Química da Água/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Idoso , Animais , Brasil/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Peixes , Contaminação de Alimentos , Cabelo/química , Humanos , Lactente , Masculino , Compostos de Mercúrio/análise , Pessoa de Meia-Idade , Alimentos Marinhos/análise , Inquéritos e Questionários , Abastecimento de Água
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