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1.
Sensors (Basel) ; 24(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38610536

RESUMO

Rising platemeters are commonly used in Ireland and New Zealand for managing intensive pastures. To assess the applicability of a commercial rising platemeter operating with a microsonic sensor to estimate herbage mass with its own equation, the objectives were (i) to validate the original equation; (ii) to identify possible factors hampering its accuracy and precision; and (iii) to develop a new equation for heterogeneous swards. A comprehensive dataset (n = 1511) was compiled on the pastures of dairy farms. Compressed sward heights were measured by the rising platemeter. Herbage mass was harvested to determine reference herbage availability. The adequacy of estimating herbage mass was assessed using root mean squared error (RMSE) and mean bias. As the adequacy of the original equation was low, a new equation was developed using multiple regression models. The mean bias and the RMSE for the new equation were overall low with 201 kg dry matter/ha and 34.6%, but it tended to overestimate herbage availability at herbage mass < 500 kg dry matter/ha and underestimate it at >2500 kg dry matter/ha. Still, the newly developed equation for the microsonic sensor-based rising platemeter allows for accurate and precise estimation of available herbage mass on pastures.


Assuntos
Calibragem , Fazendas , Irlanda
2.
Int J Occup Med Environ Health ; 37(1): 128-137, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38264916

RESUMO

OBJECTIVES: This study aimed to evaluate cytogenetic damage in the buccal mucosa of non-exposed subjects (N = 33) and insecticide-exposed fumigators (N = 31) in the urban area of Cali, Colombia. MATERIAL AND METHODS: Through a questionnaire sociodemographic data, anthropometric measurements, state of health, and lifestyle were collected. Buccal micronucleus cytome (BMCyt) assay was using for evaluate cytogenetic damage. RESULTS: The study showed that all fumigators used adequate personal protective equipment (PPE) and had low alcohol consumption. The authors did not find significant differences in BMCyt biomarkers between the groups (p > 0.05). Multivariate analysis showed a 13% increase in micronucleus (MN) frequency for every year of increasing age (OR = 1.13, p = 0.029), and higher MN with the decrease in daily fruit consumption (OR = 4.71, p = 0.084), without statistical significance. CONCLUSIONS: The results between groups could be related to healthy habits and PPE use among the subjects. Int J Occup Med Environ Health. 2024;37(1):128-37.


Assuntos
Inseticidas , Exposição Ocupacional , Humanos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Mucosa Bucal/química , Colômbia , Testes para Micronúcleos/métodos , Dano ao DNA
3.
Public Health Rep ; 138(3): 422-427, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36971286

RESUMO

Limited studies are available on how decisions and perceptions on SARS-CoV-2 vaccination have changed since the start of vaccination availability. We performed a qualitative study to identify factors critical to SARS-CoV-2 vaccination decision making and how perspectives evolved among African American/Black, Native American, and Hispanic communities disproportionately affected by COVID-19 and social and economic disadvantage. We conducted 16 virtual meetings, with 232 participants in wave 1 meetings (December 2020) and with 206 returning participants in wave 2 meetings (January and February 2021). Wave 1 vaccine concerns in all communities included information needs, vaccine safety, and speed of vaccine development. Lack of trust in government and the pharmaceutical industry was influential, particularly among African American/Black and Native American participants. Participants showed more willingness to get vaccinated at wave 2 than at wave 1, indicating that many of their information needs had been addressed. Hesitancy remained greater among African American/Black and Native American participants than among Hispanic participants. Participants in all groups indicated that conversations tailored to their community and with those most trustworthy to them would be helpful. To overcome vaccine hesitancy, we propose a model of fully considered SARS-CoV-2 vaccine decision making, whereby public health departments supply information, align with community values and recognize lived experiences, offer support for decision making, and make vaccination easy and convenient.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Tomada de Decisões , Humanos , Indígena Americano ou Nativo do Alasca/psicologia , Negro ou Afro-Americano/psicologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Hispânico ou Latino/psicologia , SARS-CoV-2 , Vacinação/psicologia
4.
J Infect Prev ; 21(1): 7-13, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32030098

RESUMO

BACKGROUND: The 2013 Cystic Fibrosis Foundation's Infection Prevention and Control Guideline (CFF IP&C) was developed to reduce the risk of acquisition and transmission of respiratory pathogens in patients with cystic fibrosis (CF). OBJECTIVE: We hypothesised that the incidence of common CF respiratory pathogens would decrease at our centre after implementation of the guideline. METHODS: All patients with CF seen at our centre from August 2012 through August 2017 who had respiratory cultures were included. Patients were excluded from incidence analysis if they did not have at least one culture per year. Quarterly data were collected for one year before and three years after implementation of the guidelines to determine the incidence and prevalence of seven organisms commonly found in respiratory cultures of patients with CF. RESULTS: Quarterly and annual incidence and prevalence rates of common organisms did not change during the study period. DISCUSSION: There were no significant differences in the incidence or prevalence of common respiratory organisms in the first three years after implementation of the CF IP&C guideline. Long-term follow-up is needed to determine if changes occur over time.

5.
Biomedica ; 39(3): 464-477, 2019 09 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31584761

RESUMO

Introduction: The exposure to organic solvents and paints has been associated with genotoxicity and a greater risk of neoplasms. However, the type of DNA damage induced in humans by the exposure to these compounds, which would help explain the mechanisms of their genotoxicity, is still not fully characterized. Due to inadequate practices of occupational safety, car painters in the informal sector are a highly exposed group to organic solvents and paints. Objective: To identify the oxidative and methylating damage in the DNA of lymphocytes of car painters exposed to organic solvents and paints. Materials and methods: Isolated peripheral blood lymphocytes from 62 painters and 62 unexposed subjects were analyzed by the modified high-throughput comet assay with the Fpg and AlkA enzymes. The categories used for the evaluation of the DNA damage were basal damage (without enzymes), oxidative and methylating damage. The measurement parameter used to establish the damage was the percentage of DNA in the tail. Results: The percentage of DNA in the tail was higher in the exposed group compared to the unexposed group (p<0.05). In the exposed group, this percentage was higher in the oxidative damage category than the baseline (16.50 vs. 12.87; p<0.001), whereas methylating damage did not show significant differences (14.00 vs. 12.87; p>0.05). Conclusion: In this study, exposure to organic solvents and paints was associated with an increase in oxidative lesions in the DNA of car painters' lymphocytes, such as the production of 8-oxodG and other formamidopyrimidine products which are considered highly mutagenic.


Introducción. La exposición a solventes orgánicos y pinturas se ha asociado con efectos genotóxicos y mayor riesgo de neoplasias. Sin embargo, aún no se ha caracterizado bien el tipo de daño que esta exposición induce en el ADN humano, ni los mecanismos por los cuales se genera. Uno de los grupos con mayor exposición a dichos solventes y pinturas son los pintores de automóviles del sector informal que trabajan sin adecuadas prácticas de seguridad ocupacional. Objetivo. Determinar el daño oxidativo y por metilación del ADN de linfocitos de pintores de automóviles expuestos a solventes orgánicos y pinturas. Materiales y métodos. Se analizaron linfocitos aislados de sangre periférica de 62 pintores y 62 sujetos no expuestos mediante el ensayo cometa de gran eficiencia acoplado a las enzimas Fpg y AlkA. Las categorías de daño en el ADN evaluadas fueron el daño basal (sin enzimas), el daño oxidativo y el daño por metilación, y el parámetro de medición, el porcentaje de ADN en la cola. Resultados. El porcentaje de ADN en la cola fue mayor en el grupo expuesto con respecto al no expuesto (p<0,05). En el grupo expuesto, dicho porcentaje fue mayor en la categoría de daño oxidativo comparado con la del basal (16,50 Vs. 12,87; p<0,001), en tanto que en el daño por metilación no se encontraron diferencias significativas (14,00 Vs. 12,87; p>0,05). Conclusión. La exposición a solventes orgánicos y pinturas se asoció con el aumento de las lesiones oxidativas del ADN de los linfocitos de pintores de automóviles, tales como la producción de 8-oxo-2'-desoxiguanosina (8-oxodG) y otros productos formamidopirimidina, los cuales se consideran considerablemente mutagénicos.


Assuntos
Dano ao DNA , Metilação de DNA , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo , Pintura/toxicidade , Solventes/toxicidade , Adulto , Automóveis , Estudos de Casos e Controles , Sobrevivência Celular , Ensaio Cometa , Estudos Transversais , DNA/efeitos dos fármacos , Humanos , Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Mutagênicos/toxicidade , Adulto Jovem
6.
Biomédica (Bogotá) ; 39(3): 464-477, jul.-set. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1038807

RESUMO

Resumen Introducción. La exposición a solventes orgánicos y pinturas se ha asociado con efectos genotóxicos y mayor riesgo de neoplasias. Sin embargo, aún no se ha caracterizado bien el tipo de daño que esta exposición induce en el ADN humano, ni los mecanismos por los cuales se genera. Uno de los grupos con mayor exposición a dichos solventes y pinturas son los pintores de automóviles del sector informal que trabajan sin adecuadas prácticas de seguridad ocupacional. Objetivo. Determinar el daño oxidativo y por metilación del ADN de linfocitos de pintores de automóviles expuestos a solventes orgánicos y pinturas. Materiales y métodos. Se analizaron linfocitos aislados de sangre periférica de 62 pintores y 62 sujetos no expuestos mediante el ensayo cometa de gran eficiencia acoplado a las enzimas Fpg y AlkA. Las categorías de daño en el ADN evaluadas fueron el daño basal (sin enzimas), el daño oxidativo y el daño por metilación, y el parámetro de medición, el porcentaje de ADN en la cola. Resultados. El porcentaje de ADN en la cola fue mayor en el grupo expuesto con respecto al no expuesto (p<0,05). En el grupo expuesto, dicho porcentaje fue mayor en la categoría de daño oxidativo comparado con la del basal (16,50 Vs. 12,87; p<0,001), en tanto que en el daño por metilación no se encontraron diferencias significativas (14,00 Vs. 12,87; p>0,05). Conclusión. La exposición a solventes orgánicos y pinturas se asoció con el aumento de las lesiones oxidativas del ADN de los linfocitos de pintores de automóviles, tales como la producción de 8-oxo-2'-desoxiguanosina (8-oxodG) y otros productos formamidopirimidina, los cuales se consideran considerablemente mutagénicos.


Abstract Introduction: The exposure to organic solvents and paints has been associated with genotoxicity and a greater risk of neoplasms. However, the type of DNA damage induced in humans by the exposure to these compounds, which would help explain the mechanisms of their genotoxicity, is still not fully characterized. Due to inadequate practices of occupational safety, car painters in the informal sector are a highly exposed group to organic solvents and paints. Objective: To identify the oxidative and methylating damage in the DNA of lymphocytes of car painters exposed to organic solvents and paints. Materials and methods: Isolated peripheral blood lymphocytes from 62 painters and 62 unexposed subjects were analyzed by the modified high-throughput comet assay with the Fpg and AlkA enzymes. The categories used for the evaluation of the DNA damage were basal damage (without enzymes), oxidative and methylating damage. The measurement parameter used to establish the damage was the percentage of DNA in the tail. Results: The percentage of DNA in the tail was higher in the exposed group compared to the unexposed group (p<0.05). In the exposed group, this percentage was higher in the oxidative damage category than the baseline (16.50 vs. 12.87; p<0.001), whereas methylating damage did not show significant differences (14.00 vs. 12.87; p>0.05). Conclusion: In this study, exposure to organic solvents and paints was associated with an increase in oxidative lesions in the DNA of car painters' lymphocytes, such as the production of 8-oxodG and other formamidopyrimidine products which are considered highly mutagenic.


Assuntos
Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Pintura/toxicidade , Solventes/toxicidade , Dano ao DNA , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo , Metilação de DNA , Automóveis , DNA/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Estudos de Casos e Controles , Sobrevivência Celular , Estudos Transversais , Ensaio Cometa , Mutagênicos/toxicidade
7.
Toxicol Mech Methods ; 26(4): 238-42, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26998723

RESUMO

Occupational exposure as a painter is associated with DNA damage and development of cancer. Comet assay has been widely adopted as a sensitive and quantitative tool for DNA damage assessment at the individual cell level in populations exposed to genotoxics. The aim of this study was to assess the application of the high-throughput comet assay, to determine the DNA damage in car spray painters. The study population included 52 car spray painters and 52 unexposed subjects. A significant increase in the %TDNA median (p < 0.001) was observed in the exposed group in comparison to the unexposed group. Neither age (%TDNA: p = 0.913) nor time of exposure (%TDNA: p = 0.398) were significantly correlated with DNA damage. The car spray painters who consumed alcohol did not show a significant increase in DNA damage compared to nonalcohol consumers (p > 0.05). The results showed an increase in DNA breaks in car spray painters exposed to organic solvents and paints; furthermore, they demonstrated the application of high-throughput comet assay in an occupational exposure study to genotoxic agents.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Dano ao DNA , Linfócitos/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Pintura/análise , Solventes/toxicidade , Estudos de Casos e Controles , Ensaio Cometa , Estudos Transversais , Ensaios de Triagem em Larga Escala , Humanos , Linfócitos/patologia , Masculino , Exposição Ocupacional/análise
8.
Toxicol Mech Methods ; 24(4): 243-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24236478

RESUMO

Paint thinners are organic-solvent complex mixtures frequently used by car painters around the world in industries and shops. Some studies have revealed the oxidative effect induced by thinner inhalation; however, its genotoxic effect is poorly studied. The aim of this study was to assess the cytotoxicity, genomic damage and DNA repair in vitro induced by commercial paint thinner 0.14 in human lymphocytes. Cytotoxicity was determined by cell-viability analysis with trypan blue after 4 h treatment with different thinner concentrations (0.025 to 1.2 µL/mL). Genomic damage was evaluated by means of the alkaline single-cell gel electrophoresis (SCGE; pH > 13) in treated cultures after 1 h with three low-cytotoxic thinner concentrations (0.05, 0.1 and 0.2 µL/mL). In order to evaluate the genomic DNA repair, one set of SCGE slides was prepared immediately after treatment, and another one was prepared after 4 h of liquid-holding recovery. A significant level of cytotoxicity was observed over the entire concentration range of paint thinner in lymphocytes (F = 175.98; p ≤ 0.001). In the SCGE % tail DNA assessment, a significant increase of lymphocyte genomic damage was evidenced (F = 72.32; p < 0.001). In addition, we found a significant decrease in the % tail DNA in thinner-treated cells after liquid-holding recovery period (all p < 0.05), demonstrating that DNA primary lesions induced by low-cytotoxic thinner concentrations are efficiently repaired. In conclusion, thinner components induce cytotoxicity and genomic damage in human lymphocytes under the study conditions, possibly by oxidative and alkylative DNA damage.


Assuntos
Reparo do DNA , Linfócitos/efeitos dos fármacos , Solventes/toxicidade , Ensaio Cometa , Humanos , Técnicas In Vitro , Linfócitos/metabolismo
9.
Water Res ; 47(10): 3282-90, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23602619

RESUMO

The haloacetic acids (HAAs) are the second-most prevalent class of drinking water disinfection by-products formed by chemical disinfectants. Previous studies have determined DNA damage and repair of HAA-induced lesions in mammalian and human cell lines; however, little is known of the genomic DNA and chromosome damage induced by these compounds in primary human cells. The aim of this study was to evaluate the genotoxic and clastogenic effects of the monoHAA disinfection by-products in primary human lymphocytes. All monoHAAs were genotoxic in primary human lymphocytes, the rank order of genotoxicity and cytotoxicity was IAA > BAA >> CAA. After 6 h of repair time, only 50% of the DNA damage (maximum decrease in DNA damage) was repaired compared to the control. This demonstrates that primary human lymphocytes are less efficient in repairing the induced damage by monoHAAs than previous studies with mammalian cell lines. In addition, the monoHAAs induced an increase in the chromosome aberration frequency as a measurement of the clastogenic effect of these compounds. These results coupled with genomic technologies in primary human cells and other mammalian non-cancerous cell lines may lead to the identification of biomarkers that may be employed in feedback loops to aid water chemists and engineers in the overall goal of producing safer drinking water.


Assuntos
Desinfetantes/toxicidade , Desinfecção/métodos , Água Potável/química , Linfócitos/efeitos dos fármacos , Mutagênicos/toxicidade , Acetatos/química , Acetatos/toxicidade , Adulto , Células Cultivadas , Aberrações Cromossômicas , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Desinfetantes/química , Humanos , Ácido Iodoacético/química , Ácido Iodoacético/toxicidade , Masculino , Índice Mitótico , Testes de Mutagenicidade
10.
J Asthma ; 49(7): 673-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22799435

RESUMO

OBJECTIVES: The relationship between exhaled nitric oxide (FeNO) and asthma severity or control is inconsistent. Active smoking lowers FeNO, but the relationship between passive smoking and FeNO is less clear. Children may be exposed to low-level environmental tobacco smoke (ETS) or thirdhand smoke, even if parents avoid smoking in the presence of their children. Our hypothesis was that FeNO is lower in children with asthma exposed to low-level ETS when compared with those who are not exposed. METHODS: Children with stable asthma, 8-18 years of age, on low- or medium-dose inhaled corticosteroids (ICS) were enrolled. Spirometry, Asthma Control Questionnaire (ACQ), FeNO, exhaled breath condensate pH (EBC pH), and EBC ammonia were compared between children with and without ETS exposure as determined by urinary cotinine. RESULTS: Thirty-three subjects were enrolled, of which 10 (30%) had urinary cotinine levels ≥1 ng/ml. There were no significant differences between the two groups in age, sex, BMI percentile, atopy status, FEV(1), EBC pH, or EBC ammonia. Median ACQ was 0.29 (IQR: 0.22-0.57) for those with cotinine levels <1 ng/ml and 0.64 (IQR: 0.57-1.1) for those with cotinine levels of ≥1 ng/ml, p = .02. Median FeNO (ppb) was 23.9 (IQR: 15.2-34.5) for unexposed subjects and 9.6 (IQR: 5.1-15.8) for exposed subjects, p = .008. CONCLUSIONS: Children with asthma on low to medium doses of ICS and recent low-level ETS exposure have lower FeNO levels when compared with non-ETS-exposed subjects. Exposure to low-level ETS or thirdhand smoke may be an important variable to consider when interpreting FeNO as a biomarker for airway inflammation.


Assuntos
Corticosteroides/administração & dosagem , Asma/metabolismo , Testes Respiratórios , Óxido Nítrico/metabolismo , Poluição por Fumaça de Tabaco/efeitos adversos , Administração por Inalação , Adolescente , Asma/diagnóstico , Asma/tratamento farmacológico , Asma/etiologia , Biomarcadores , Criança , Feminino , Humanos , Masculino
11.
Biopreserv Biobank ; 8(4): 203-209, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23386924

RESUMO

Pfizer, Inc.'s Tissue Bank, in conjunction with Pfizer's BioBank (biofluid repository), endeavored to create an overarching internal software package to cover all general functions of both research facilities, including sample receipt, reconciliation, processing, storage, and ordering. Business process flow diagrams were developed by the Tissue Bank and Informatics teams as a way of characterizing best practices both within the Bank and in its interactions with key internal and external stakeholders. Besides serving as a first step for the software development, such formalized process maps greatly assisted the identification and communication of best practices and the optimization of current procedures. The diagrams shared here could assist other biospecimen research repositories (both pharmaceutical and other settings) for comparative purposes or as a guide to successful informatics design. Therefore, it is recommended that biorepositories consider establishing formalized business process flow diagrams for their laboratories, to address these objectives of communication and strategy.

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