RESUMO
OBJECTIVES: To explore the performance of low-dose computed tomography (LDCT) with deep learning reconstruction (DLR) for the improvement of image quality and assessment of lung parenchyma. METHODS: Sixty patients underwent chest regular-dose CT (RDCT) followed by LDCT during the same examination. RDCT images were reconstructed with hybrid iterative reconstruction (HIR) and LDCT images were reconstructed with HIR and DLR, both using lung algorithm. Radiation exposure was recorded. Image noise, signal-to-noise ratio, and subjective image quality of normal and abnormal CT features were evaluated and compared using the Kruskal-Wallis test with Bonferroni correction. RESULTS: The effective radiation dose of LDCT was significantly lower than that of RDCT (0.29 ± 0.03 vs 2.05 ± 0.65 mSv, p < 0.001). The mean image noise ± standard deviation was 33.9 ± 4.7, 39.6 ± 4.3, and 31.1 ± 3.2 HU in RDCT, LDCT HIR-Strong, and LDCT DLR-Strong, respectively (p < 0.001). The overall image quality of LDCT DLR-Strong was significantly better than that of LDCT HIR-Strong (p < 0.001) and comparable to that of RDCT (p > 0.05). LDCT DLR-Strong was comparable to RDCT in evaluating solid nodules, increased attenuation, linear opacity, and airway lesions (all p > 0.05). The visualization of subsolid nodules and decreased attenuation was better with DLR than with HIR in LDCT but inferior to RDCT (all p < 0.05). CONCLUSION: LDCT DLR can effectively reduce image noise and improve image quality. LDCT DLR provides good performance for evaluating pulmonary lesions, except for subsolid nodules and decreased lung attenuation, compared to RDCT-HIR. CLINICAL RELEVANCE STATEMENT: The study prospectively evaluated the contribution of DLR applied to chest low-dose CT for image quality improvement and lung parenchyma assessment. DLR can be used to reduce radiation dose and keep image quality for several indications. KEY POINTS: ⢠DLR enables LDCT maintaining image quality even with very low radiation doses. ⢠Chest LDCT with DLR can be used to evaluate lung parenchymal lesions except for subsolid nodules and decreased lung attenuation. ⢠Diagnosis of pulmonary emphysema or subsolid nodules may require higher radiation doses.
Assuntos
Aprendizado Profundo , Humanos , Melhoria de Qualidade , Doses de Radiação , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Interpretação de Imagem Radiográfica Assistida por Computador/métodosRESUMO
In recent years, the extensive distribution of phthalates (PAEs) in soils has attracted increasing attention. In this study, the concentrations of six types of PAEs were measured in five dissimilar regions of the Yellow River Delta (YRD), and regional differences, pollution characteristics and health risks of PAEs pollution were investigated. The detection rate of PAEs was 100 %, and the concentration range of Σ6PAEs was 0.709-9.565 mg/kg, with an average of 3.258 ± 2.031 mg/kg. There were different spatial distribution differences of PAEs in soils of the YRD, with residential living, chemical industrial, and crop growing areas being the main areas of PAEs distribution. It was worth noting that di (2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) are prominent contributors to PAEs in soils of the YRD. Correlation analyses showed that soils physicochemical properties such as SOM, TN and CEC were closely correlated to the transport and transformation of PAEs. Use by petrochemical industries, accumulation of plasticizers, additives (derived from cosmetics, food, pharmaceutical), fertilizers, pesticides, plastics, and atmospheric deposition are the principal sources of PAEs in the YRD. A health risk assessment showed that the health risk caused by non-dietary intake of PAEs was low and considered acceptable. PAEs pollution in the YRD soil is particularly noteworthy, especially for the prevention and control of DEHP and DBP pollution. This study provides basic data for an effective control of soil PAEs pollution in the YRD, which is conducive to the sustainable development of the region.
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Dietilexilftalato , Ácidos Ftálicos , Poluentes do Solo , Solo/química , Ácidos Ftálicos/análise , Dietilexilftalato/análise , Rios/química , Poluentes do Solo/análise , Ésteres/análise , Dibutilftalato/análise , Medição de Risco , Verduras , ChinaRESUMO
Background: Healthcare workers' relationship with industry is not merely an agent mediating between consumer and vendor, but they are also inventors of the interventions they exist to deliver. Driven by the background of the digital health era, scientific research and technological (Sci-tech) innovation in the medical field are becoming more and more closely integrated. However, scholars shed little light on Sci-tech relevance to evaluate the innovation performance of healthcare organizations, a distinctive feature of healthcare organizations' innovation in the digital health era. Methods: Academic publications and patents are the manifestations of scientific research outputs and technological innovation outcomes, respectively. The study extracted data from publications and patents of 159 hospitals in China to evaluate their innovation performance. A total of 18 indicators were constructed, four of which were based on text similarity match and represented the Sci-tech relevance. We then applied factor analyses, analytical hierarchy process, and logistic regression to construct an evaluation model. We also examined the relationship between hospitals' innovation performance and their geographical locations. Finally, we implemented a mediation analysis to show the influence of digital health on hospital innovation performance. Results: A total of 16 indicators were involved, four of which represented the Sci-tech including the number of articles matched per patent (NAMP), the number of patents matched per article (NPMA), the proportion of highly matched patents (HMP), and the proportion of highly matched articles (HMA). Indicators of HMP (r = 0.52, P = 2.40 × 10-12), NAMP (r = 0.52, P = 2.54 × 10-12), and NPMA (r = 0.51, P = 5.53 × 10-12) showed a strong positive correlation with hospital innovation performance score. The evaluation model in this study was different from other Chinese existing hospital ranking systems. The regional innovation performance index (RIP) of healthcare organizations is highly correlated with per capita disposable income (r = 0.58) and regional GDP (r = 0.60). There was a positive correlation between digital health innovation performance scores and overall hospital innovation performance scores (r = 0.20). In addition, the hospitals' digital health innovation performance affected the hospital's overall innovation score with the mediation of Sci-tech relevance indicators (NPMA and HMA). The hospitals' digital health innovation performance score showed a significant correlation with the number of healthcare workers (r = 0.44). Conclusion: This study constructed an assessment model with four invented indicators focusing on Sci-tech relevance to provide a novel tool for researchers to evaluate the innovation performance of healthcare organizations in the digital health era. The regions with high RIP were concentrated on the eastern coastal areas with a higher level of economic development. Therefore, the promotion of scientific and technological innovation policies could be carried out in advance in areas with better economic development. The innovations in the digital health field by healthcare workers enhance the Sci-tech relevance in hospitals and boost their innovation performance. The development of digital health in hospitals depends on the input of medical personnel.
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Atenção à Saúde , Tecnologia Digital , Hospitais , China , Invenções , TecnologiaRESUMO
In this study, eighteen 3.30-m-long sediment profiles were sampled in Maozhou River. In order to investigate the sediment pollution status and potential sources of heavy metals, we performed heavy metal contents, grain size, organic matter concentration, moisture concentration and total phosphorus analysis, and assessed the ecological risk of heavy metal pollution in the study area using enrichment coefficient, geo-accumulation index and potential ecological risk index. The results indicated that the heavy metal concentrations in the Maozhou River sediments were 3.73-417 times higher than the soil background in Guangdong Province and the average concentrations were 0.447-15.1 times higher than Chinese lacustrine sediments. The Cr, Ni, Cu, Zn, Cd and Pb contents were significantly correlated with each other (p < 0.01), indicating similar deposition process. In addition, spatial and vertical distribution of heavy metals showed similar variation patterns and extreme high contents are distributed in the interchange area. The ecological risk of Maozhou River was much higher than other river sediments in Guangdong Province, especially for Cu, Cd and Ni. The variation pattern of potential ecological risk index is similar with that of heavy metals and the assessment results indicated high ecological risk in the Maozhou River sediments, which is in good agreement with the EF and Igeo results. This study would provide some references for the treatment of heavy metals' pollution in Maozhou River.
Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Medição de Risco , Rios , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: There is a need to develop novel therapies which could be beneficial to patients with prostate cancer (CaP) including those who are predisposed to poor outcome, such as African-Americans. This study investigates the role of ROBO1-pathway in predicting outcome and race-based disparity in patients with CaP. METHODS AND RESULTS: Aided by RNA sequencing-based DECIPHER-testing and immunohistochemical (IHC) analysis of tumors we show that ROBO1 is lost during the progressive stages of CaP, a prevalent feature in African-Americans. We show that the loss of ROBO1 predicts high-risk of recurrence, metastasis and poor outcome of androgen-deprivation therapy in radical prostatectomy-treated patients. These data identified an aggressive ROBO1deficient /DOCK1+ve sub-class of CaP. Combined genetic and IHC data showed that ROBO1 loss is accompanied by DOCK1/Rac1 elevation in grade-III/IV primary-tumors and Mets. We observed that the hypermethylation of ROBO1-promoter contributes to loss of expression that is highly prevalent in African-Americans. Because of limitations in restoring ROBO1 function, we asked if targeting the DOCK1 could be an ideal strategy to inhibit progression or treat ROBO1deficient metastatic-CaP. We tested the pharmacological efficacy of CPYPP, a selective inhibitor of DOCK1 under in vitro and in vivo conditions. Using ROBO1-ve and ROBO1+ve CaP models, we determined the median effective concentration of CPYPP for growth. DOCK1-inhibitor treatment significantly decreased the (a) Rac1-GTP/ß-catenin activity, (b) transmigration of ROBO1deficient cells across endothelial lining, and (c) metastatic spread of ROBO1deficient cells through the vasculature of transgenicfl Zebrafish model. CONCLUSION: We suggest that ROBO1 status forms as predictive biomarker of outcome in high-risk populations such as African-Americans and DOCK1-targeting therapy has a clinical potential for treating metastatic-CaP.
Assuntos
Negro ou Afro-Americano/genética , Proteínas do Tecido Nervoso/genética , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/genética , Receptores Imunológicos/genética , Proteínas rac de Ligação ao GTP/genética , Animais , Linhagem Celular Tumoral , Metilação de DNA , Disparidades nos Níveis de Saúde , Humanos , Imuno-Histoquímica , Masculino , Metástase Neoplásica , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/deficiência , Regiões Promotoras Genéticas , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Receptores Imunológicos/biossíntese , Receptores Imunológicos/deficiência , População Branca/genética , Peixe-Zebra , Proteínas rac de Ligação ao GTP/antagonistas & inibidores , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas RoundaboutRESUMO
In order to evaluate the pollution levels of and risk from heavy metals in the atmospheric deposition of different functional urban districts, dust samples were collected from 20 sampling sites in typical industrial, traffic, residential, and educational districts of Nanjing. The concentrations of As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, Ti, V, and Zn were analyzed. The potential ecological risk and health risk were evaluated using the potential ecological risk index and U.S. EPA's health risk assessment models. Enrichment factors, correlation analysis, and principal component analysis were used to analyze the sources of heavy metals. Results showed that the concentrations of As, Cd, Co, Cr, Cu, Fe, Mn, Pb, and Zn were the highest in the industrial district and the concentrations of Ba, Ni, Ti, and V were the highest in the traffic district. The value of the potential ecological risk index was the highest in the industrial district and lowest in the educational district. Meanwhile, the ecological risk of Cr was the highest, achieving a moderate ecological hazard level. None of the studied heavy metals had noncarcinogenic risk or carcinogenic risk, according to the results of health risk assessment. Source analysis indicated that heavy metals in the atmospheric deposition from the study areas were mainly from traffic and industrial activities, coal combustion, natural process and life sources.
Assuntos
Monitoramento Ambiental , Poluição Ambiental/análise , Metais Pesados/análise , China , Poeira , Poluição Ambiental/efeitos adversos , Humanos , Metais Pesados/efeitos adversos , Medição de RiscoRESUMO
Laboratory analysis of trace metals using inductively coupled plasma (ICP) spectroscopy is not cost effective, and the complex spatial distribution of soil trace metals makes their spatial analysis and prediction problematic. Thus, for the health risk assessment of exposure to trace metals in soils, portable X-ray fluorescence (PXRF) spectroscopy was used to replace ICP spectroscopy for metal analysis, and robust geostatistical methods were used to identify spatial outliers in trace metal concentrations and to map trace metal distributions. A case study was carried out around an industrial area in Nanjing, China. The results showed that PXRF spectroscopy provided results for trace metal (Cu, Ni, Pb and Zn) levels comparable to ICP spectroscopy. The results of the health risk assessment showed that Ni posed a higher non-carcinogenic risk than Cu, Pb and Zn, indicating a higher priority of concern than the other elements. Sampling locations associated with adverse health effects were identified as 'hotspots', and high-risk areas were delineated from risk maps. These 'hotspots' and high-risk areas were in close proximity to and downwind from petrochemical plants, indicating the dominant role of industrial activities as the major sources of trace metals in soils. The approach used in this study could be adopted as a cost-effective methodology for screening 'hotspots' and priority areas of concern for cost-efficient health risk management.
Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Oligoelementos/análise , China , Análise Custo-Benefício , Monitoramento Ambiental/estatística & dados numéricos , Humanos , Indústrias , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Análise Espacial , Espectrometria por Raios XRESUMO
We report recent progress in the development of a precision test for individualized use of the VEGF-A targeting drug bevacizumab for treating ovarian cancer. We discuss the discovery model stage (i.e., past feasibility modeling and before conversion to the production test). Main results: (a) Informatics modeling plays a critical role in supporting driving clinical and health economic requirements. (b) The novel computational models support the creation of a precision test with sufficient predictivity to reduce healthcare system costs up to $30 billion over 10 years, and make the use of bevacizumab affordable without loss of length or quality of life.
Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Bevacizumab/uso terapêutico , Carcinoma Epitelial do Ovário/tratamento farmacológico , Biologia Computacional , Terapia de Alvo Molecular , Neoplasias Ovarianas/tratamento farmacológico , Medicina de Precisão/métodos , Terapia Assistida por Computador , Simulação por Computador , Redução de Custos , Ciência de Dados , Atenção à Saúde/economia , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Biológicos , Terapia de Alvo Molecular/economia , Qualidade de VidaRESUMO
Contents of heavy metals involving As, Cd, Cr, Cu, Ni, Pb and Zn from atmospheric deposition in 10 parks of Nanjing were analyzed. The pollution level, ecological risk and health risk were evaluated using Geoaccumulation Index, Potential Ecological Risk Index and the US EPA Health Risk Assessment Model, respectively. The results showed that the pollution levels of heavy metals in Swallow Rock Park, Swallow Rock Park and Mochou Lake Park were higher than the others. Compared to other cities such as Changchun, Wuhan and Beijing, the contents of heavy metals in atmospheric deposition of parks in Nanjing were higher. The evaluation results of Geoaccumulation Index showed that Pb was at moderate pollution level, Zn and Cu were between moderate and serious levels, while Cd was between serious and extreme levels. The ecological risk level of Cd was high. The assessment results of Health Risk Assessment Model indicated that there was no non-carcinogenic risk for all the seven heavy metals. For carcinogenic risk, the risks of Cd, Cr and Ni were all negligible (Risk < 1 x 10â»6), whereas As had carcinogenic risk possibility but was considered to be acceptable (10â»6 < Risk < 10â»4).
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Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise , China , Cidades , Ecologia , Modelos Teóricos , Parques RecreativosRESUMO
Arsenic, Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn total concentrations and bioaccessibilities in 15 urban park dust samples were determined. The oral bioaccessibility measured by the Simple Bioaccessibility Extraction Test (SBET) decreased in the order of Pb>Cd>Zn>Mn>Cu>Co>V>Ni>As>Cr. The Tomlinson pollution load index (PLI) and geoaccumulation index (I(geo)) were calculated to evaluate the pollution extent to which the samples were contaminated. Sources were identified using principal component analysis and Pb isotope compositions. Most elements except Co and V were considered to mainly originate from anthropogenic sources. Non-carcinogenic and carcinogenic risks to humans through urban park dust exposure were assessed using the oral bioaccessibilities of the elements. Ingestion was the main pathway for non-carcinogenic risk. The hazard quotients were below the safe level (=1) for all elements, however, Pb (0.154) and As (0.184) posed potential higher risks to children than adults. The carcinogenic effects occurring were below the acceptable level (10(-4)) for As and <10(-6) for Cd, Co, Cr, and Ni.
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Arsênio/análise , Poeira/análise , Poluição Ambiental/análise , Metais Pesados/análise , Parques Recreativos , Oligoelementos/análise , Adulto , Criança , China , Cidades , Humanos , Parques Recreativos/normas , Medição de RiscoRESUMO
In this study, a genetically engineered Escherichia coli strain, HBUT-D (ΔpflB Δpta ΔfrdABCD ΔadhE Δald ΔcscR), was initially evaluated on a laboratory scale (7 L) in a glucose (130 g L(-1)) mineral salts medium for d-lactic acid fermentation using 6N KOH, Ca(OH)2 or NH4OH as the neutralizing agent. Fermentations neutralized by Ca(OH) 2 achieved a volumetric productivity of 6.35 g L(-1) h(-1), tripling that achieved by KOH (1.71 g L(-1) h(-1)) and NH4OH (1.5 g L(-1) h(-1)). The facilitative effect of Ca(OH)2 neutralization was then demonstrated on a pilot scale (6 ton vessel, 130 kg glucose ton(-1)), resulting in a volumetric productivity of 6 kg ton(-1) h(-1), a titer of 126 kg ton(-1), a yield of 97%, and an optical purity of 99.5%. These results demonstrated that E. coli HBUT-D is a promising strain for large scale d-lactic acid fermentation using mineral salts medium and Ca(OH)2 for neutralization.
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Hidróxido de Cálcio/farmacologia , Escherichia coli/metabolismo , Fermentação/efeitos dos fármacos , Ácido Láctico/metabolismo , Engenharia Metabólica/métodos , Biocatálise/efeitos dos fármacos , Análise Custo-Benefício , Escherichia coli/efeitos dos fármacos , Engenharia Metabólica/economia , Projetos PilotoRESUMO
Azoxystrobin has been widely used in recent years. The present study investigated the oxidative stress and DNA damage effects of azoxystrobin on earthworms (Eisenia fetida). Earthworms were exposed to different azoxystrobin concentrations in an artificial soil (0, 0.1, 1, and 10mg/kg) and sampled on days 7, 14, 21, and 28. Superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (POD), glutathione-S-transferase (GST), reactive oxygen species (ROS), and malondialdehyde (MDA) content were measured by an ultraviolet spectrophotometer to determine the antioxidant responses and lipid peroxidation. Single cell gel electrophoresis (SCGE) was used to detect DNA damage in the coelomocytes. Compared with these in the controls, earthworms exposed to azoxystrobin had excess ROS accumulation and greater SOD, POD, and GST activity while the opposite trend occurred for CAT activity. MDA content increased after 14-day exposure, and DNA damage was enhanced with an increase in the concentration of azoxystrobin. In conclusion, azoxystrobin caused oxidative stress leading to lipid peroxidation and DNA damage in earthworms.
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Dano ao DNA , Metacrilatos/toxicidade , Oligoquetos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pirimidinas/toxicidade , Poluentes do Solo/toxicidade , Análise de Variância , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Ensaio Cometa , Glutationa Transferase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Oligoquetos/metabolismo , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estrobilurinas , Superóxido Dismutase/metabolismoRESUMO
The aim of this study was to evaluate the reliability and the validity of the Chinese version of the Dentine Hypersensitivity Experience Questionnaire (DHEQ). After translation and cross-cultural adaptation following international guidelines, 110 patients with dentine hypersensitivity were recruited to complete the questionnaire. The reliability of the Chinese version of the DHEQ was evaluated using internal consistency and test-retest methods. Construct validity was determined based on factor analysis, discriminative validity (by comparing the subscale scores difference in the degree of sensitivity being investigated), and convergent validity (by analyzing the correlation between DHEQ subscale scores and the global rating of oral health question). Cronbach's alpha value (internal reliability) for the total DHEQ score was 0.95 and the intraclass correlation coefficient (ICC) value (test-retest reliability) was 0.85. Construct validity was determined by factor analysis, extracting eight factors, accounting for 74% of the variance. All items had factor loadings of >0.40. In addition, the Chinese version of the DHEQ was found to be valid for distinguishing patients with varying degrees of dentine hypersensitivity. In terms of convergent validity, the impact scale was significantly highly correlated to the global oral health rating. The results suggest that the Chinese version of the DHEQ has satisfactory psychometric properties and is applicable for patients with dentine hypersensitivity in China.
Assuntos
Efeitos Psicossociais da Doença , Sensibilidade da Dentina/psicologia , Psicometria/métodos , Qualidade de Vida , China , Comparação Transcultural , Inquéritos de Saúde Bucal , Humanos , Saúde Bucal , Reprodutibilidade dos Testes , Perfil de Impacto da Doença , Inquéritos e QuestionáriosRESUMO
Dispersive solid-phase extraction (DSPE) cleanup combined with accelerated solvent extraction (ASE) is described here as a new approach for the extraction of carbamate pesticides in Radix Glycyrrhizae samples prior to UPLC-MS-MS. In the DSPE-ASE method, 15 carbamate pesticides were extracted from Radix Glycyrrhizae samples with acetonitrile by the ASE method at 60 °C with a 5 min heating time and two static cycles. Cleanup of a 1 mL aliquot of the extract by the DSPE method used 20 mg PSA (primary secondary amine), 50 mg Al(2)O(3)-N, and 20 mg GCB (graphitized carbon black) (as cleanup sorbents) under the determined optimum conditions. The linearity of the method was in the range of 10 to 200 ng/mL with correlation coefficients (r(2)) of more than 0.996. The limits of detection were approximately 0.2 to 5.0 µg/kg. The method was successfully used for the analysis of target pesticides in Radix Glycyrrhizae samples. The recoveries of the carbamate pesticides at the spiking levels of 50, 100, and 200 µg/kg ranged from 79.7% to 99.3% with relative standard deviations lower than 10%. This multi-residue analytical method allows for a rapid, efficient, sensitive and reliable determination of target pesticides in Radix Glycyrrhizae and other medicinal herbs.
Assuntos
Carbamatos/isolamento & purificação , Glycyrrhiza/química , Resíduos de Praguicidas/isolamento & purificação , Extração em Fase Sólida/métodos , Acetonitrilas/química , Cromatografia Líquida de Alta Pressão/economia , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Sensibilidade e Especificidade , Extração em Fase Sólida/economia , Espectrometria de Massas por Ionização por Electrospray/economia , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/economia , Espectrometria de Massas em Tandem/métodosRESUMO
The homolytic O-H bond dissociation energy (BDE) of phenol was determined from diffusion Monte Carlo (DMC) calculations using single determinant trial wave functions. DMC gives an O-H BDE of 87.0 +/- 0.3 kcal/mol when restricted Hartree-Fock orbitals are used and a BDE of 87.5 +/- 0.3 kcal/mol with restricted B3LYP Kohn-Sham orbitals. These results are in good agreement with the extrapolated B3P86 results of Costa Cabral and Canuto (88.3 kcal/mol), the recommended experimental value of Borges dos Santos and Martinho Simões (88.7 +/- 0.5 kcal/mol), and the G3 (88.2 kcal/mol), CBS-APNO (88.2 kcal/mol), CBS-QB3 (87.1 kcal/mol) results of Mulder.
RESUMO
Endosulfan, as one of the most widely used organochlorine pesticides in the world, has increased the public concern about genotoxicity in soil ecosystems. The comet assay has been widely used in the fields of genetic toxicology and environmental biomonitoring. In the present study we conducted comet assay of endosulfan in earthworm (Eisenia foetida) and white clover (Trifolium repens L.), which are sensitive organisms suitable for acting as a bioindicator for agricultural ecosystems. Earthworms were exposed to endosulfan concentrations of 0.1, 1.0, and 10.0 mg/kg in the soil. White clover roots were immersed in hydroponic pots containing nutrient solutions of different endosulfan concentrations: 0.1, 1.0, and 10.0 mg/L. Tissues from each treatment were collected on the 7th, 14th, 21st, and 28th days of treatment process. Significant effects (p < 0.01) of both concentrations and times of exposure were observed. And endosulfan induced DNA damage in earthworm and white clover nuclei. The comet assay can be used as a reliable tool for early detection of endosulfan.