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1.
J Fish Dis ; 40(1): 65-71, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27260260

RESUMO

This is a study of vertebral deformities in ornamental koi based on computed radiography and skeletons cleaned by dermestid beetles (Dermestes maculatus). All koi developed gradual onset of swimming abnormalities as adults. Extensive intervertebral osteophyte formation correlated with age of fish and was associated with hindquarter paresis in one koi. Vertebral compression and fusion were the most common spinal deformities occurring at multiple sites, similar to findings in other farmed fish. Site-specific spinal deformities were thought to develop due to differences in swimming behaviour and rates of vertebral growth. One koi had offspring with spinal deformities. Spinal deformities are significant problems in both European and Australian food fish hatcheries. The heritability of vertebral deformities in farmed fish is reportedly low unless there is concurrent poor husbandry or nutritional deficiencies. The specific aetiologies for vertebral deformities in koi in this study could not be ascertained. Current knowledge on spinal deformities in the better studied European food fish species suggests multifactorial aetiologies. Future research should include prospective longitudinal studies of larger numbers of koi from hatch and consideration of all potential risk factors such as husbandry, nutrition, temperature, photoperiod and genetics.


Assuntos
Carpas/anormalidades , Doenças dos Peixes/congênito , Doenças da Coluna Vertebral/veterinária , Coluna Vertebral/anormalidades , Animais , Feminino , Doenças dos Peixes/diagnóstico , Masculino , Radiografia/veterinária , Doenças da Coluna Vertebral/congênito , Doenças da Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem
2.
Br J Cancer ; 112(1): 177-84, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25314066

RESUMO

BACKGROUND: As more patients are treated by haematopoietic stem cell transplantation (HSCT), development of secondary malignancy (SM) becomes an increasingly common issue in long-term survivors. METHODS: We conducted a nationwide population-based study of the Taiwanese population to analyse patients who received HSCT between January 1997 and December 2010. Standardised incidence ratios (SIRs) were used to compare the risk of SM in HSCT patients and the general population. Multivariate analysis was performed to identify independent predictors of SM. RESULTS: Patients receiving HSCT had a significantly greater risk of developing SM (SIR 2.00; 95% confidence interval (CI) 1.45-2.69; P<0.001). Specifically, the incidence increased for cancers of the oral cavity (SIR 14.18) and oesophagus (SIR 14.75) after allogeneic HSCT. Multivariate analysis revealed an increased SIR for cancer in patients who received the immunosuppressant azathioprine. The risk of SM also increased with greater cumulative doses of azathioprine. CONCLUSIONS: This study demonstrates an increased incidence of SM in Taiwanese patients who received allogeneic HSCT, especially for cancers of the oral cavity and oesophagus. This finding is different from results in populations of Western countries. Physicians should be cautious about azathioprine use for graft-vs-host disease after HSCT.


Assuntos
Azatioprina/administração & dosagem , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/estatística & dados numéricos , Segunda Neoplasia Primária/epidemiologia , Adulto , Estudos de Coortes , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Sobreviventes , Taiwan/epidemiologia , Condicionamento Pré-Transplante/efeitos adversos , Adulto Jovem
3.
Psychol Med ; 45(8): 1601-12, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25388623

RESUMO

BACKGROUND: Previous studies have implicated the relationship between environmental phthalate exposure and attention deficit hyperactivity disorder (ADHD) symptoms of childhood, but no studies have been conducted in children who have a confirmed diagnosis of ADHD obtained through meticulous diagnostic testing. We aimed to determine whether phthalate metabolites in urine would be higher in children with ADHD than in those without ADHD and would correlate with symptom severity and cortical thickness in ADHD children. METHOD: A cross-sectional examination of urine phthalate metabolite concentrations was performed; scores for ADHD symptoms, externalizing problems, and continuous performance tests were obtained from 180 children with ADHD, and brain-imaging data were obtained from 115 participants. For the control group, children without ADHD (N = 438) were recruited. Correlations between phthalate metabolite concentrations and clinical measures and brain cortical thickness were investigated. RESULTS: Concentrations of phthalate metabolites, particularly the di(2-ethylhexyl) phthalate (DEHP) metabolite, were significantly higher in boys with ADHD than in boys without ADHD. Concentrations of the di-n-butyl phthalate (DBP) metabolite were significantly higher in the combined or hyperactive-impulsive subtypes compared to the inattentive subtype, and the metabolite was positively correlated with the severity of externalizing symptoms. Concentrations of the DEHP metabolite were negatively correlated with cortical thickness in the right middle and superior temporal gyri. CONCLUSIONS: The results of this study suggest an association between phthalate concentrations and both the diagnosis and symptom severity of ADHD. Imaging findings suggest a negative impact of phthalates on regional cortical maturation in children with ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno do Deficit de Atenção com Hiperatividade/urina , Córtex Cerebral/patologia , Ácidos Ftálicos/urina , Adolescente , Análise de Variância , Criança , Estudos Transversais , Exposição Ambiental , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , República da Coreia , Índice de Gravidade de Doença
4.
Haemophilia ; 20(6): 741-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24834860

RESUMO

Haemostasis is associated with the development and dissemination of cancer. Whether cancer incidence is increased in haemophiliacs remains uncertain; thus, we aimed to further examine this issue. By using data from the National Health Insurance Research Database in Taiwan, we obtained a cohort of 683 patients with haemophilia A, and compared the incidence rate ratio (IRR) of cancer in this cohort with an age- and sex-matched control of 6830 patients. The log-rank test was used to compare Kaplan-Meier curve of the cumulative cancer incidence between two cohorts. Cox regressions were used to identify independent risk factors of cancer in the study patients. The cancer incidence of patients with haemophilia A was significantly higher compared to the control group (IRR 1.95, 95% CI 1.18-3.09, P = 0.008) during the 14-year follow-up period. The non-lymphoma and non-liver cancer incidence in the haemophilia A cohort remained higher than that of the matched control (P = 0.050 by the log-rank test). The multivariate Cox proportional hazards analysis indicated that age (per year, HR 1.09, 95% CI 1.06-1.12, P < 0.001) was the only significant risk factor for cancer development in haemophilia patients. Patients with haemophilia A had higher cancer incidence than the age- and sex-matched patients, especially for the elderly. With increasing life expectancy for haemophiliacs, physicians should be aware of their cancer development.


Assuntos
Hemofilia A/complicações , Neoplasias/epidemiologia , Neoplasias/etiologia , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Comorbidade , Feminino , Seguimentos , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Vigilância da População , Modelos de Riscos Proporcionais , Sistema de Registros , Risco , Taiwan/epidemiologia , Adulto Jovem
5.
Allergy ; 68(4): 517-23, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23347096

RESUMO

BACKGROUND: Exposure to ambient air pollution and bronchiolitis are risk factors for asthma. The aim of this study was to investigate the effect of air pollution on the development of asthma in children with past episodes of bronchiolitis. METHODS: A prospective 2-year follow-up survey consisting of parental responses to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire, and allergy evaluations were conducted in 1743 children with a mean age of 6.8 years. Recent 5-year exposure to air pollution was estimated using a geographic information system. RESULTS: Higher exposure to ozone was associated with airway hyper-responsiveness (PC20  ≤ 16 mg/ml) at enrollment (odds ratio [OR] = 1.60, 95% CI [confidence interval] = 1.13-2.27) and with new episodes of wheezing during the 2-year period (OR = 1.92, 95% CI = 0.96-3.83). Past episodes of bronchiolitis were associated with both current wheezing and physician-diagnosed asthma. When the two factors were combined, the prevalence of bronchial hyper-reactivity (OR = 2.96, 95% CI = 1.41-6.24) and new wheezing (OR = 4.17, 95% CI = 0.89-19.66) as well as current wheezing and physician-diagnosed asthma was even greater (P for trend <0.05 for all). In children with both risk factors, lung function was significantly decreased, with atopic children being particularly vulnerable. CONCLUSION: In children, the interaction between air pollution and past episodes of bronchiolitis resulted in a greater prevalence of asthma and pointed to an association with bronchial hyper-reactivity and decreased lung function. These results suggest mechanisms underlying the development of asthma.


Assuntos
Poluição do Ar/efeitos adversos , Asma/etiologia , Bronquiolite/complicações , Asma/diagnóstico , Asma/epidemiologia , Biomarcadores , Criança , Feminino , Humanos , Masculino , Ozônio/efeitos adversos , Prevalência , Estudos Prospectivos , Testes de Função Respiratória , Sons Respiratórios , Inquéritos e Questionários
6.
Psychol Med ; 43(1): 209-19, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22608159

RESUMO

BACKGROUND: We examined the cross-sectional relationship between environmental tobacco smoke exposure, continuous performance test (CPT) measures, and attention deficit hyperactivity disorder (ADHD) or learning disability symptoms in school-aged children. METHOD: In total, 989 children (526 boys, mean age 9.1 ± 0.7 years), recruited from five South Korean cities participated in this study. We used urine cotinine as a biomarker for environmental tobacco smoke exposure, and obtained the children's scores on a CPT. Parents completed the Korean versions of the ADHD rating scale-IV (ADHD-RS) and learning disability evaluation scale (LDES). Using generalized linear mixed model (GLMM), we assessed the associations between urine cotinine concentrations, neuropsychological variables, and symptoms of ADHD and learning disabilities. Additionally, we conducted structural equation models to explore the effects' pathways. RESULTS: After adjusting for a range of relevant covariates, GLMM showed urinary cotinine levels were significantly and positively associated with CPT scores on omission errors, commission errors, response time, and response time variability, and with parent- and teacher-rated ADHD-RS scores. In addition, urine cotinine levels were negatively associated with LDES scores on spelling and mathematical calculations. The structural equation model revealed that CPT variables mediated the association between urine cotinine levels and parental reports of symptoms of ADHD and learning disabilities. CONCLUSIONS: Our data indicate that environmental exposure to tobacco smoke is associated with ADHD and learning disabilities in children, and that impairments in attention and inhibitory control probably mediate the effect.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Cotinina/urina , Deficiências da Aprendizagem/fisiopatologia , Poluição por Fumaça de Tabaco/efeitos adversos , Transtorno do Deficit de Atenção com Hiperatividade/urina , Criança , Estudos Transversais , Feminino , Humanos , Inibição Psicológica , Deficiências da Aprendizagem/urina , Masculino , Modelos Psicológicos , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , República da Coreia
7.
Eur Respir J ; 36(6): 1270-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20351028

RESUMO

Volatile organic compounds (VOCs) are reported to cause adverse effects on pulmonary function in occupationally exposed workers. However, evidence is lacking on the effect in the general population. We hypothesised that VOCs impair pulmonary function through enhancing oxidative stress, especially in the elderly population. A longitudinal panel study of 154 elderly people was performed in South Korea. Repeated spirometric tests were performed up to eight times on different days for each subject. We also measured urinary concentrations of metabolites of the VOC and markers of oxidative stress (malondialdehyde and 8-oxo-2'-deoxyguanosine) on the same day of spirometric tests. A mixed linear regression model was used to evaluate the association among the VOC metabolites, oxidative stress markers and spirometric tests. We found that the urinary levels of hippuric acid and methylhippuric acid, which are metabolites of toluene and xylene, respectively, were significantly associated with reduction of forced expiratory volume in 1 s (FEV1), FEV1/forced vital capacity (FVC), and forced expiratory flow at 25-75% of FVC. We also found significant associations between the metabolites of VOCs and the markers of oxidative stress. In addition, the oxidative stress markers were associated with pulmonary function parameters. This study suggests that exposure to toluene and xylene exert a harmful effect on pulmonary function by exacerbating oxidative stress in elderly people.


Assuntos
Exposição Ambiental , Pneumopatias/induzido quimicamente , Pulmão/efeitos dos fármacos , Estresse Oxidativo , Tolueno/toxicidade , Compostos Orgânicos Voláteis/toxicidade , Xilenos/toxicidade , 8-Hidroxi-2'-Desoxiguanosina , Idoso , Idoso de 80 Anos ou mais , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Feminino , Hipuratos/urina , Humanos , Estudos Longitudinais , Pulmão/fisiopatologia , Pneumopatias/fisiopatologia , Masculino , Malondialdeído/urina , Pessoa de Meia-Idade , República da Coreia , Respiração/efeitos dos fármacos , Testes de Função Respiratória , Tolueno/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Xilenos/metabolismo
8.
Br J Cancer ; 101(3): 526-9, 2009 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-19550421

RESUMO

BACKGROUND: Few cohort studies have investigated Epstein-Barr virus (EBV) infection before the occurrence of gastric cancer. METHODS: Among 14,440 cohort participants, 100 incident gastric cancer cases were individually matched to two controls. Epstein-Barr virus antibodies IgG and IgA against viral capsid antigen (VCA), EBV nuclear antigen (EBNA) antibody IgG, and early antigen (EA) antibody IgG were measured using enzyme immunoassays (EIAs). RESULTS: The highest titres of VCA IgG (odds ratio (OR): 1.37, 95% confidence interval (CI): 0.62-3.06) or EBNA IgG (OR: 0.87, 95% CI: 0.51-1.46) were not associated with gastric cancer risk. CONCLUSION: Higher levels of VCA IgG or EBNA IgG were not associated with increased risk of gastric adenocarcinoma in Koreans.


Assuntos
Anticorpos Antivirais/sangue , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Gástricas/virologia , Adulto , Idoso , Proteínas do Capsídeo/imunologia , Estudos de Casos e Controles , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Feminino , Infecções por Helicobacter/complicações , Helicobacter pylori , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/etiologia
10.
Bone Marrow Transplant ; 40(9): 871-4, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17704789

RESUMO

Blood, buccal swab and hair follicles are among the most commonly used sources for forensic science, parentage testing and personal identification. A total of 29 patients who have had a sustained engraftment from 15 months to 21.5 years after allogeneic hematopoietic stem cell transplantation (HSCT) without rejection, relapse or chronic GVHD involving oral mucosa were enrolled for a chimerism study. PCR-amplified short tandem repeat analyses were conducted per patient every 3 months for at least three consecutive times. The results for blood were all donor type except one who had a mixed chimerism, 14.5 years after receiving a transplant for lymphoma. As for buccal swab, mixed chimerism ranging from 10 to 96% donor origin was noted for 28 recipients except the one who had mixed chimerism of blood and retained total recipient type. In contrast, hair follicles were 100% recipient type for the entire group. It is concluded that the hair follicle is devoid of adult stem cell plasticity and may serve as a reliable source of recipient's origin when pre-transplant DNA fingerprinting or reference DNA is not available for people who have successfully received allogeneic HSCT while in need of a personal identification.


Assuntos
Folículo Piloso , Transplante de Células-Tronco Hematopoéticas , Quimeras de Transplante , Adolescente , Adulto , Feminino , Ciências Forenses , Sobrevivência de Enxerto , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Paternidade , Reação em Cadeia da Polimerase/métodos
11.
Eur J Clin Nutr ; 70(4): 511-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26443041

RESUMO

BACKGROUND/OBJECTIVES: Concerns of a growing obesity epidemic have increased since the association between obesity in parents and that in offspring was reported. However, the evidence regarding whether the energy-saving efficiency of obese parents is conveyed to their offspring and the duration of the expression of such transmitted efficiency is limited. SUBJECTS/METHODS: We included 7647 matching sets of parent-offspring trios from South Korea. Multiple linear regression models were performed to estimate the energy-saving efficiency, as assessed by the associations between energy intake and obesity-related indices (waist-to-height ratio, waist circumference and body mass index z-score), and to compare the energy-saving efficiency of offspring of obese and non-obese parents. All analyses were based on a complex sample design and were stratified by gender and age. RESULTS: We identified a parental influence on obesity, that is, the more obese the parent, the higher the obesity-related indices of their offspring, in both genders and all age groups. The energy-saving efficiency of child offspring was highest when both parents were obese and lowest when both were non-obese; this difference was significant (P<0.05) with regard to the energy-saving efficiency of all types of intake studied, except fat. However, the energy-saving efficiency of obese and non-obese parents did not differ when their offspring were adolescents and adults. CONCLUSIONS: The critical window for transmission of energy-saving efficiency is limited to childhood. These findings suggest that children of obese parents should be more emphatically advised to maintain a balanced diet and to engage in regular physical activity.


Assuntos
Povo Asiático , Metabolismo Energético , Obesidade/metabolismo , Adolescente , Adulto , Índice de Massa Corporal , Criança , Pré-Escolar , Estudos Transversais , Dieta , Exercício Físico , Feminino , Humanos , Modelos Lineares , Masculino , Inquéritos Nutricionais , Pais , República da Coreia , Circunferência da Cintura , Razão Cintura-Estatura , Adulto Jovem
12.
J Hazard Mater ; 294: 41-6, 2015 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25841085

RESUMO

Abatement of fluorinated compounds (FCs) used in semiconductor and display industries has received an attention due to the increasingly stricter regulation on their emission. We have developed a 2.45GHz microwave plasma torch with reverse vortex reactor (RVR). In order to design a reverse vortex plasma reactor, we calculated a volume fraction and temperature distribution of discharge gas and waste gas in RVR by ANSYS CFX of computational fluid dynamics (CFD) simulation code. Abatement experiments have been performed with respect to SF6, NF3 by varying plasma power and N2 flow rates, and FCs concentration. Detailed experiments were conducted on the abatement of NF3 and SF6 in terms of destruction and removal efficiency (DRE) using Fourier transform infrared (FTIR). The DRE of 99.9% for NF3 was achieved without an additive gas at the N2 flow rate of 150 liter per minute (L/min) by applying a microwave power of 6kW with RVR. Also, a DRE of SF6 was 99.99% at the N2 flow rate of 60 L/min using an applied microwave power of 6kW. The performance of reverse vortex reactor increased about 43% of NF3 and 29% of SF6 abatements results definition by decomposition energy per liter more than conventional vortex reactor.


Assuntos
Poluentes Atmosféricos , Fluoretos , Micro-Ondas , Compostos de Nitrogênio , Hexafluoreto de Enxofre , Poluentes Atmosféricos/química , Poluentes Atmosféricos/efeitos da radiação , Pressão Atmosférica , Fluoretos/química , Fluoretos/efeitos da radiação , Hidrodinâmica , Compostos de Nitrogênio/química , Compostos de Nitrogênio/efeitos da radiação , Gases em Plasma , Semicondutores , Espectroscopia de Infravermelho com Transformada de Fourier , Hexafluoreto de Enxofre/química , Hexafluoreto de Enxofre/efeitos da radiação , Resíduos
13.
Int J Tuberc Lung Dis ; 19(1): 58-64, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25519791

RESUMO

BACKGROUND: Tuberculosis (TB) is a serious problem for patients undergoing haematopoietic stem cell transplantation (HSCT) in TB-endemic areas; however, data on these patients are limited. METHODS: We obtained data on 2040 HSCT recipients from the Registry of Catastrophic Illness in Taiwan from 1997 to 2006. We also obtained data on age-, sex- and enrolment date-matched controls from the Longitudinal Health Insurance Database. The cumulative incidence of active TB in HSCT recipients and controls and risk factors for TB were analysed. RESULTS: Among 2040 HSCT recipients identified, 39 (1.9%) had newly diagnosed TB. The incidence rate was 688 per 100 000 person-years. The 10-year cumulative TB incidence was respectively 3.52% and 0.38% in HSCT recipients and controls (P < 0.001). HSCT was an independent risk factor for TB compared with matched controls. Among post-HSCT patients, independent risk factors for TB included age ⩾18 years and allogeneic recipients with graft-versus-host disease (GVHD). Post-HSCT patients with subsequent TB had a higher mortality rate than those without TB (P < 0.001). CONCLUSION: HSCT is associated with an increased risk of TB in endemic regions. Older age and development of chronic GVHD are independent predictors of late onset active TB in HSCT recipients.


Assuntos
Doença Enxerto-Hospedeiro/epidemiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplantados , Tuberculose/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Pré-Escolar , Comorbidade , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/microbiologia , Humanos , Imunossupressores/uso terapêutico , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
14.
Environ Health Perspect ; 105(7): 744-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9294721

RESUMO

Nickel compounds are recognized to cause nasal and lung cancers. Magnesium is an effective protector against nickel-induced carcinogenesis in vivo, although its mechanisms of protection remain elusive. The effects of magnesium carbonate on the cytotoxicity and genotoxicity induced by nickel subsulfide were examined with respect to the inhibition of cell proliferation, micronuclei formation, DNA-protein cross-link formation, and intranuclear nickel concentration. The generation of reactive oxygen by nickel chloride was also analyzed by observing 8-hydroxy-deoxyguanosine formation from deoxyguanosine in the presence and absence of magnesium chloride. The suppression of up to 64% of the proliferation of BALB/3T3 fibroblasts by nickel subsulfide (1 microgram/ml) was reversed by magnesium. The nickel compound increased not only the number of micronuclei but also the amount of DNA-protein cross-links examined with CHO and BALB/3T3 cells, respectively. These genotoxic effects of nickel were again lessened by magnesium carbonate. In addition, the cellular accumulation of nickel increased 80-fold with nickel subsulfide treatment and decreased with magnesium carbonate treatment. Nickel also enhanced 8-hydroxy-deoxyguanosine formation in the presence of H2O2 and ascorbic acid, where magnesium played another suppressive role. In fact, inhibition by magnesium was still observed even in the absence of nickel treatment. These results suggest that the protective role of magnesium in nickel-induced cytotoxicity and genotoxicity can be attributed to its ability to reduce either the intracellular nickel concentration or reactive oxygen formation.


Assuntos
Carcinógenos/toxicidade , Dano ao DNA , Magnésio/farmacologia , Mutagênicos/farmacologia , Níquel/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Animais , Ácido Ascórbico/química , Células CHO , Carcinógenos/farmacologia , Divisão Celular , Núcleo Celular/química , Cricetinae , Desoxiguanosina/análogos & derivados , Óxido de Deutério/química , Fibroblastos , Técnicas In Vitro , Magnésio/química , Níquel/farmacologia
15.
Environ Health Perspect ; 107(11): 873-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10544154

RESUMO

To evaluate the relative importance of various measures of particulate and gaseous air pollution as predictors of daily mortality in Inchon, South Korea, the association between total daily mortality and air pollution was investigated for a 20-month period (January 1995 through August 1996). Poisson regression was used to regress daily death counts on each air pollutant, controlling for time trends, season, and meteorologic influences such as temperature and relative humidity. Regression coefficients of a 5-day moving average of particulate matter less than or = to 10 microm in aerodynamic diameter (PM(10)) on total mortality were positively significant when considered separately and simultaneously with other pollutants in the model. PM(10) remained significant when the models were confined to cardiovascular or respiratory mortality. Sulfur dioxide (SO(2)) and carbon monoxide (CO) were significantly related to respiratory mortality in the single-pollutant model. Ozone exposure was not statistically significant with regard to mortality in the above models, and graphic analysis showed that the relationship was nonlinear. A combined index of PM(10), nitrogen dioxide, SO(2), and CO seemed to better explain the exposure-response relationship with total mortality than an individual air pollutant. Pollutants should be considered together in the risk assessment of air pollution, as opposed to measuring the risk of individual pollutants.


Assuntos
Poluição do Ar/efeitos adversos , Mortalidade , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Coreia (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Análise de Regressão , Medição de Risco
16.
J Dent Res ; 64(2): 82-4, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3855886

RESUMO

It has been shown in laboratory and animal studies that tooth enamel becomes considerably more reactive toward low levels of fluoride after receiving pre-treatment which forms dicalcium phosphate dihydrate (DCPD) in the enamel as an intermediate. This in vitro study was undertaken to determine the effect on human enamel fluoride uptake of incorporating DCPD-forming rinses into a conventional fluoride rinsing program. In one group, enamel samples received a one-minute rinse with 0.2% NaF each day for 20 days. Samples in the second group were treated identically, except that they were also given a one-minute DCPD-forming rinse prior to the first, sixth, eleventh, and sixteenth fluoride rinses. At the end of the rinsing program, all samples were washed in 1 M KOH to remove labile fluorides. The enamel biopsy data showed that the fluoride uptake resulting from 0.2% NaF alone was not statistically significant, whereas uptake produced by the DCPD-forming plus NaF rinses was significant. The results suggest that the DCPD-forming rinse may improve the efficacy of fluoride rinse programs.


Assuntos
Fosfatos de Cálcio/farmacologia , Esmalte Dentário/metabolismo , Fluoretos/metabolismo , Apatitas/metabolismo , Fosfatos de Cálcio/administração & dosagem , Esmalte Dentário/análise , Fluoretos/administração & dosagem , Fluoretos/análise , Humanos , Concentração de Íons de Hidrogênio , Antissépticos Bucais , Fluoreto de Sódio/administração & dosagem
17.
J Dent Res ; 59(8): 1447-52, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6931119

RESUMO

Powdered human enamel treated for three minutes each with a CaHPO4 x 2H2O forming solution and a fluoride solution, and then suspended in "synthetic saliva" for 72 hours acquired a large amount of apatitic fluoride. This apatitic fluoride appears to form after the fluoride treatment.


Assuntos
Fosfatos de Cálcio , Esmalte Dentário , Fluoretos , Apatitas , Fluoreto de Cálcio , Fenômenos Químicos , Química , Esmalte Dentário/análise , Fluoretos/análise , Humanos , Saliva
18.
Eur J Clin Nutr ; 58(10): 1365-71, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15054416

RESUMO

OBJECTIVE: It has been known that maternal oxidative stress during pregnancy plays an important role in fetal growth. However, the association between antioxidant vitamin levels and birth outcomes is not conclusive. We investigated the relationship between maternal serum levels of vitamins C and E during the second trimester and birth weight and length. DESIGN: Prospective cohort study. SETTING: Outpatient-clinic of obstetrics, Ewha Womans University Hospital, South Korea. SUBJECTS AND METHODS: The study subjects were 239 healthy, pregnant women who visited an obstetric clinic for antenatal care, and their singleton live births, in Seoul, Korea, between August 2001 and March 2003. We measured the levels of vitamins C and E in maternal serum during the period 24-28 gestational weeks. Each woman was interviewed for dietary intake by trained interviewers during the second trimester. RESULTS: The serum concentration of maternal vitamin C during the second trimester was significantly associated with birth weight and length in the group of full-term deliveries. An increase of 1 microg/ml in the serum vitamin C level increased the birth weight by 27.2 g and the birth length by 0.17 cm. When we considered the levels of vitamins C and E together in the relationship with birth weight and length, we found that the heaviest birth weight and the longest birth length belonged to the group of upper vitamin C/upper vitamin E. However, dietary intake estimated by 24-h recall method was not a predictor of the levels of serum vitamins C and E. CONCLUSION: We found that maternal serum vitamin C levels during the second trimester were positively correlated with birth weight and length in full-term babies. We also found that birth weight and length were highest when the levels of both vitamins C and E were high. Our results indicate the importance of antioxidant nutrient balance for pregnant women who are exposed to various oxidants through food, drinking water, or inhaled air.


Assuntos
Ácido Ascórbico/sangue , Peso ao Nascer , Estatura , Desenvolvimento Fetal/efeitos dos fármacos , Segundo Trimestre da Gravidez/sangue , Vitamina E/sangue , Antioxidantes/administração & dosagem , Antioxidantes/análise , Ácido Ascórbico/administração & dosagem , Peso ao Nascer/efeitos dos fármacos , Estatura/efeitos dos fármacos , Estudos de Coortes , Dieta , Sinergismo Farmacológico , Feminino , Humanos , Recém-Nascido , Masculino , Troca Materno-Fetal , Rememoração Mental , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Vitamina E/administração & dosagem
19.
Toxicol Lett ; 108(2-3): 217-23, 1999 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-10511265

RESUMO

The measurement of the pyrene metabolite, 1-hydroxypyrene, in human urine has been used to assess recent exposure to polycyclic aromatic hydrocarbons (PAH). The objective of this study was to see whether genetic polymorphisms in metabolic enzymes could explain some of the variation in urinary 1-hydroxypyrene glucuronide (1-OHPG) excretion in relation to smoking. Forty-seven male hospital workers, who were not occupationally exposed to PAH, participated in this study. The urine samples were analyzed for 1-OHPG utilizing immunoaffinity chromatography and synchronous fluorescence spectroscopy. The analysis of GSTM1 and GSTT1 polymorphism was performed by PCR. The 1-OHPG concentration in the urine of the hospital workers was 0.57 +/- 0.85 micromol/mol creatinine, and ranged from 0.02 to 5.04 mciromol/mol creatinine. Cigarette smoking was significantly correlated with urinary 1-OHPG (r = 0.3976, P = 0.0056). The 1-OHPG excretion in GSTM1-deficient smokers was higher than that in GSTM1-positive smokers. On the other hand, 1-OHPG excretion was higher in GSTT1-positive smokers than in GSTT1-deficient smokers. It is important to note the variability of individual PAH metabolite excretion due to different GSTM1 and GSTT1 genotypes.


Assuntos
Glucuronatos/análise , Glutationa Transferase/urina , Pirenos/análise , Fumar/urina , Adulto , Exposição Ambiental/análise , Genótipo , Glutationa Transferase/deficiência , Humanos , Masculino , Pessoa de Meia-Idade , Recursos Humanos em Hospital , Hidrocarbonetos Policíclicos Aromáticos/urina , Análise de Regressão
20.
Mutat Res ; 426(1): 63-9, 1999 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-10320751

RESUMO

This study was carried out to evaluate whether bitumen cytotoxicity is enhanced when bitumen treatment is combined with UVA exposure. We also evaluated the oxidative processes in bitumen-induced DNA damage, and attempted to identify the DNA damage caused by bitumen and UVA exposures, either alone or in combination. The effects of bitumen and UVA on cell proliferation were examined using HL 60 cells. DNA-protein crosslinks (DPCs) were assessed using a K-SDS assay, and reactive oxygen species formation was detected by 8-OH-dG formation. We evaluated the formations of double-strand breaks (DSB) using lambdaDNA/HindIII and single-strand breaks (SSB) using PM2 DNA. The cytotoxicity assay showed enhanced suppression of cell proliferation when bitumen exposure and UVA exposure were combined. Combined exposure caused significant increases in DPCs over either exposure alone. Incubation of deoxyguanosine (dG) with bitumen or UVA showed an increase in 8-hydroxy-2'-deoxyguanosine (8-OH-dG) levels when compared with controls, and combined exposure enhanced this effect. An evaluation of agarose gel bands showed that DSB and SSB were not formed following exposure to bitumen and UVA. This fact indicates that bitumen and UVA may be involved in genotoxic processes by producing oxygen free radicals and that combined exposure enhances these effects.


Assuntos
Dano ao DNA , Hidrocarbonetos/toxicidade , Raios Ultravioleta , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Cocarcinogênese , Células HL-60 , Humanos , Espécies Reativas de Oxigênio
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