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Objective: Tissue uptake and distribution of nano-/microplastics was studied at a single high dose by gavage in vivo. Methods: Fluorescent microspheres (100 nm, 3 µm, and 10 µm) were given once at a dose of 200 mg/(kgâbody weight). The fluorescence intensity (FI) in observed organs was measured using the IVIS Spectrum at 0.5, 1, 2, and 4 h after administration. Histopathology was performed to corroborate these findings. Results: In the 100 nm group, the FI of the stomach and small intestine were highest at 0.5 h, and the FI of the large intestine, excrement, lung, kidney, liver, and skeletal muscles were highest at 4 h compared with the control group ( P < 0.05). In the 3 µm group, the FI only increased in the lung at 2 h ( P < 0.05). In the 10 µm group, the FI increased in the large intestine and excrement at 2 h, and in the kidney at 4 h ( P < 0.05). The presence of nano-/microplastics in tissues was further verified by histopathology. The peak time of nanoplastic absorption in blood was confirmed. Conclusion: Nanoplastics translocated rapidly to observed organs/tissues through blood circulation; however, only small amounts of MPs could penetrate the organs.
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Microplásticos , Poluentes Químicos da Água , Plásticos , Fígado , Microesferas , PulmãoRESUMO
Objective: This study was designed to provide the evidences on the toxicokinetics of microplastics (MPs) and nanoplastics (NPs) in the bodies of mammals. Methods: 100 nm, 3 µm, and 10 µm fluorescent polystyrene (PS) beads were administered to mice once by gavage at a dose of 200 mg/kg body weight. The levels and change of fluorescence intensity in samples of blood, subcutaneous fat, perirenal fat, peritesticular fat, cerebrum, cerebellum, testis, and epididymis were measured at 0.5, 1, 2, and 4 h after administration using an IVIS Spectrum small-animal imaging system. Histological examination, confocal laser scanning, and transmission electron microscope were performed to corroborate the findings. Results: After confirming fluorescent dye leaching and impact of pH value, increased levels of fluorescence intensity in blood, all adipose tissues examined, cerebrum, cerebellum, and testis were measured in the 100 nm group, but not in the 3 and 10 µm groups except in the cerebellum and testis at 4 h for the 3 µm PS beads. The presence of PS beads was further corroborated. Conclusion: After a single oral exposure, NPs are absorbed rapidly in the blood, accumulate in adipose tissues, and penetrate the blood-brain/testis barriers. As expected, the toxicokinetics of MPs is significantly size-dependent in mammals.
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Microplásticos , Tecido Nervoso , Masculino , Animais , Camundongos , Plásticos , Genitália , Tecido Adiposo , Poliestirenos/toxicidade , MamíferosRESUMO
OBJECTIVE: The objective of this study was to estimate the current status of prevalence, awareness, treatment and control rate of hypertension in adult residents living in rural area of Liaoning Province, North China. METHODS: The screening was finished in 2008, probability proportional to size sampling method was used to select the representative sample. Blood pressure was measured in 153481 adults (aged > 35 yr), information on history of hypertension and use of antihypertensive medications was obtained by use of a standard questionnaire. RESULTS: Overall, hypertension prevalence rate was 41.9%, the age-specific hypertension prevalence rate was 25.0%, 37.7%, 50.2%, and 64.9% in men and 22.1%, 41.1%, 56.6% and 70.2% in women age 35 to 44 years, 45 to 54 years, 55 to 64 years, and above 65 years, respectively. Among hypertensive patients, awareness rate was only 54.1%, 39.7% patients received antihypertensive medication and blood pressure control rate (< 140/90 mm Hg) was 6.9% in all participants and was 9.3% in treated hypertensive patients. CONCLUSION: Our results indicates that hypertension prevalence is highly while awareness, treatment and control rate of hypertension was low in rural areas of northeast China. These results underscore the urgent need to develop comprehensive strategies to improve prevention, detection, and treatment of hypertension in rural population of Liaoning province.
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Conhecimentos, Atitudes e Prática em Saúde , Hipertensão/epidemiologia , Hipertensão/prevenção & controle , População Rural , Adulto , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Inquéritos e QuestionáriosRESUMO
RETRACTION: The paper entitled "Effects of Outdoor and Indoor Air Pollution on Respiratory Health of Children from Kindergarten in Northern China" by Guang-hui Dong et al, which was published online on 02 May 2007, has been withdrawn at the authors' request.
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Numerous studies have assessed the concentration-response (C-R) relationships between long-term exposure to particulate matter (PM) and mortality from cardiopulmonary diseases, but few studies have evaluated the C-R relationships between PM exposure and morbidity of chronic respiratory diseases or their symptoms, and to date no systematic review has been published on the characteristics of the C-R curves between PM exposure and respiratory disease morbidity. Screening of all available studies in Medline identified ten studies with figures or scatter plots showing the C-R relationships between PM exposure and chronic bronchitis or chronic cough/phlegm. The C-R relationships showed ballistic 'S' shaped curves, linear in the low to moderate PM range and flattening out in the high PM range. Moreover, the shape and level of the C-R curves differed markedly between susceptible and nonsusceptible populations. New evidence from a prospective cohort study confirmed that the C-R relationship between PM reduction and beneficial effects on respiratory health may be due to the decreased incidence of respiratory symptoms and increased recovery in individuals with symptoms of bronchitis. Additional studies are needed to assess the C-R relationships between different PM contents and chronic health parameters, especially in geographic areas with high PM pollution and in more susceptible populations. Evidence from prospective cohort studies in developing countries with areas of high PM pollution may help evaluate the burden of chronic respiratory disease attributable to PM pollution and air quality standards.
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OBJECTIVE: To study the prevalence of mental disorders among the Chinese youths aged 15 - 34 years, in rural areas and to identify risk factors related to suicide. METHODS: A consecutive sampling strategy was used for suicidal cases in 16 randomly selected counties in Hunan, Liaoning, and Shandong provinces. Between 2005 and 2008, a total of 392 suicide cases were recruited with 416 community controls at the same age range, selected from the same areas one family member together with one close friend of each suicidal case were interviewed, using the psychological autopsy (PA) method. The same method with structured instruments was performed on the two informants for each control in the same community. SCID was used for the diagnosis of mental disease. RESULTS: 48.0% of the suicides were diagnosed as having at least one mental disorder episode, in comparison with only 3.8% among the controls. It was found that mental disorder was the most important risk factor for the Chinese young suicide cases in the rural areas. CONCLUSION: As seen in the Western countries, mental disorder had also been the number one correlate on suicidal cases in China, with the difference as other social and psychological factors might have played relatively more important roles in China.
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Transtornos Mentais/epidemiologia , Suicídio , Adolescente , Adulto , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Masculino , Fatores de Risco , População Rural , Adulto JovemRESUMO
OBJECTIVE: To evaluate the mortality trend of chronic obstructive pulmonary disease (COPD) among residents in Liaoning province during the period of 1984-2010. METHODS: The cut-points were ascertained by Monte Carlo Permutation test in COPD mortality trend lines of Poisson regression with Joinpoint Regression Program. The annual percent changes (APC) before and after the cut-points and the average annual percent change (AAPC) of COPD mortality were examined during the period. RESULTS: Significant declining trends on COPD mortality among the urban population during 1984-2010 and that of rural population during 1999-2009 were found. The standardized urban COPD mortality rate by Chinese population declined from 243.93 per 100 thousand in 1984 to 33.13 per 100 thousand in 2010. The urban 26 years AAPC was -5.8%. While the mortality in the rural population decreased from 251.33 per 100 thousand in 1999 to 102.25 per 100 thousand in 2009 in the same population. The rural 10 years' AAPC was -6.8%. The total trend of COPD mortality reduction was mainly resulted from the fast decline of bronchitis mortality. The AAPC of COPD mortality of the urban population was -9.0% and greater than that of the rural population (-6.8%) from 1999 to 2009. The urban population had a lower COPD mortality than that of the rural population. In urban area, males had a higher COPD mortality than females, however, in the rural area, males had a lower COPD mortality than the females. CONCLUSION: The COPD mortality among the residents of Liaoning province declined significantly from 1984 to 2010. Further studies are needed to confirm the viewpoint of WHO that the prevalence of COPD would have a continuous increasing trend in China.
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Doença Pulmonar Obstrutiva Crônica/mortalidade , China/epidemiologia , Feminino , Humanos , Masculino , População Rural , População UrbanaRESUMO
OBJECTIVE: To analyze the impact of mortality by age and causes of death on life expectancy at birth among residents of Liaoning province. METHODS: The study included mortality data of urban and rural residents in two periods (1973 - 1975 and 2004 - 2005). Both Abridged Life Table and Arriaga method were used to calculate and to decompose life expectancy changes by age and causes of death. RESULTS: From 1975 - 2005, the life expectancy increased by 4.68 years in urban residents and 4.91 for rural residents with a higher increment among females than males. Most part of the increase (76.27% and 82.81% for urban and rural male, 58.76% and 62.13% for urban and rural female) in life expectancy within the last 30 years could be explained by the decrease of mortality in the populations at age 0 - 4 and 55 - 74. Diseases related to respiratory system and infectious disease were contributing the most to the gap in life expectancy between the two periods. Mortality of heart disease was a negative contributor to the changes in life expectancy among both rural and urban residents while the mortalities of cerebro-vascular diseases and malignant tumors were the negative contributors for rural residents. CONCLUSION: The increase of life expectancy in the last 30 years was mainly resulted from the decrease of mortality on both respiratory and infectious diseases. Control of chronic diseases is the key point to increase the life expectancy among the residents of Liaoning province.