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1.
Math Biosci Eng ; 19(5): 4856-4880, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35430844

RESUMO

In this paper, we revisit the notion of infection force from a new angle which can offer a new perspective to motivate and justify some infection force functions. Our approach can not only explain many existing infection force functions in the literature, it can also motivate new forms of infection force functions, particularly infection forces depending on disease surveillance of the past. As a demonstration, we propose an SIRS model with delay. We comprehensively investigate the disease dynamics represented by this model, particularly focusing on the local bifurcation caused by the delay and another parameter that reflects the weight of the past epidemics in the infection force. We confirm Hopf bifurcations both theoretically and numerically. The results show that, depending on how recent the disease surveillance data are, their assigned weight may have a different impact on disease control measures.


Assuntos
Doenças Transmissíveis , Epidemias , Doenças Transmissíveis/epidemiologia , Diclorodifenil Dicloroetileno , Humanos
2.
Int J Mol Sci ; 23(8)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35457000

RESUMO

Endocrine-disrupting chemicals (EDCs) are chemical substances that can interfere with the normal function of the endocrine system. EDCs are ubiquitous and can be found in a variety of consumer products such as food packaging materials, personal care and household products, plastic additives, and flame retardants. Over the last decade, the impact of EDCs on human health has been widely acknowledged as they have been associated with different endocrine diseases. Among them, a subset called metabolism-disrupting chemicals (MDCs) is able to promote metabolic changes that can lead to the development of metabolic disorders such as diabetes, obesity, hepatic steatosis, and metabolic syndrome, among others. Despite this, today, there are still no definitive and standardized in vitro tools to support the metabolic risk assessment of existing and emerging MDCs for regulatory purposes. Here, we evaluated the following two different pancreatic cell-based in vitro systems: the murine pancreatic ß-cell line MIN6 as well as the human pancreatic ß-cell line EndoC-ßH1. Both were challenged with the following range of relevant concentrations of seven well-known EDCs: (bisphenol-A (BPA), bisphenol-S (BPS), bisphenol-F (BPF), perfluorooctanesulfonic acid (PFOS), di(2-ethylhexyl) phthalate (DEHP), cadmium chloride (CdCl2), and dichlorodiphenyldichloroethylene (DDE)). The screening revealed that most of the tested chemicals have detectable, deleterious effects on glucose-stimulated insulin release, insulin content, electrical activity, gene expression, and/or viability. Our data provide new molecular information on the direct effects of the selected chemicals on key aspects of pancreatic ß-cell function, such as the stimulus-secretion coupling and ion channel activity. In addition, we found that, in general, the sensitivity and responses were comparable to those from other in vivo studies reported in the literature. Overall, our results suggest that both systems can serve as effective tools for the rapid screening of potential MDC effects on pancreatic ß-cell physiology as well as for deciphering and better understanding the molecular mechanisms that underlie their action.


Assuntos
Compostos Benzidrílicos , Disruptores Endócrinos , Animais , Diclorodifenil Dicloroetileno , Disruptores Endócrinos/toxicidade , Humanos , Insulina , Camundongos , Plásticos
3.
Environ Health ; 21(1): 42, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35439992

RESUMO

BACKGROUND: Exposure to persistent environmental organic pollutants may contribute to the development of obesity among children. Chlordecone is a persistent organochlorine insecticide with estrogenic properties that was used in the French West Indies (1973-1993) and is still present in the soil and the water and food consumed by the local population. We studied the association between prenatal and childhood exposure to chlordecone and the adiposity of prepubertal children. METHODS: Within the Timoun Mother-Child Cohort Study in Guadeloupe (French West Indies), 575 children had a medical examination at seven years of age, including adiposity measurements. A Structural Equation Modeling approach was used to create a global adiposity score from four adiposity indicators: the BMI z-score, percentage of fat mass, sum of the tricipital and subscapular skinfold thickness, and waist-to-height ratio. Chlordecone concentrations were measured in cord blood at birth and in the children's blood at seven years of age. Models were adjusted for prenatal and postnatal covariates. Sensitivity analyses accounted for co-exposure to PCB-153 and pp'-DDE. Mediation analyses, including intermediate birth outcomes, were conducted. RESULTS: Prenatal chlordecone exposure tended to be associated with increased adiposity at seven years of age, particularly in boys. However, statistical significance was only reached in the third quartile of exposure and neither linear nor non-linear trends could be formally identified. Consideration of preterm birth or birth weight in mediation analyses did not modify the results, as adjustment for PCB-153 and pp'-DDE co-exposures. CONCLUSION: Globally, we found little evidence of an association between chlordecone exposure during the critical in utero or childhood periods of development and altered body-weight homeostasis in childhood. Nevertheless, some associations we observed at seven years of age, although non-significant, were consistent with those observed at earlier ages and would be worth investing during further follow-ups of children of the Timoun Mother-Child Cohort Study when they reach puberty.


Assuntos
Clordecona , Nascimento Prematuro , Efeitos Tardios da Exposição Pré-Natal , Adiposidade , Criança , Estudos de Coortes , Diclorodifenil Dicloroetileno , Feminino , Guadalupe/epidemiologia , Humanos , Recém-Nascido , Masculino , Relações Mãe-Filho , Obesidade , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Índias Ocidentais
4.
Artigo em Inglês | MEDLINE | ID: mdl-35409545

RESUMO

The current study aimed to investigate temporal trends of serum organochlorine pesticide (OCP) concentrations in the general United States population, approximately 30 years after the prohibition of OCP usage, by using National Health and Nutrition Examination Survey data. The least square geometric means and percent change in OCP concentrations were calculated by a survey weighted multiple linear regression model. Over 2005-2016, OCP concentrations showed significant downward temporal trends. Females had substantially higher concentrations of ß-Hexachlorocyclohexane (ß-HCH), p,p'-DDE and p,p'-DDT, but lower concentrations of Hexachlorobenzene (HCB) and trans-nonachlor. In addition, females had a more rapid decrease in p,p'-DDT levels over time than males. The overall OCP concentrations increased with age, and the two oldest age groups (aged 40-59 and 60+ years) had substantially lower rates of decrease than the younger age groups (aged 12-39 years). Concentrations and declines in OCPs (except for trans-nonachlor) were higher in Mexican Americans than both non-Hispanic Whites and non-Hispanic Blacks. There is a particular need for the ongoing monitoring of these banned chemicals, and measures should be taken to mitigate the exposure of vulnerable populations, including adults aged over 60, Mexican Americans, females for ß-HCH, p,p'-DDE and p,p'-DDT, and males for HCB and trans-nonachlor.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Adulto , DDT , Diclorodifenil Dicloroetileno , Monitoramento Ambiental , Feminino , Hexaclorobenzeno , Humanos , Hidrocarbonetos Clorados/análise , Masculino , Inquéritos Nutricionais , Praguicidas/análise , Estados Unidos
5.
Environ Res ; 210: 113018, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35227676

RESUMO

We have performed a systematic review and meta-analysis of the association between DDT/DDE and diabetes, searching PubMed, Embase, and Cochrane for relevant articles published up to August 30, 2021, and eventually including 43 publications. Our researchers evaluate included studies' quality and risk of bias via the recommended tool. This study uses meta-analyses of random effects of each exposure and outcome to estimate combined odds ratios (ORs) and 95% confidence intervals (CIs). Our research identified 43 cross-sectional, case-control, and cohort studies, including 40,141 individuals in America, Europe, Asia, and Africa. The summary ORs (95% CIs) of incident diabetes were 1.61 (1.10-2.39) for DDT, 1.67 (1.41-1.98) for DDE. The subgroup analysis indicated that the association is significantly higher in the region of Asia for both DDT (OR = 2.73) and DDE (OR = 2.62). Besides, we also tried various types of stratification to identify the more influential confounding factors, among which regional factors have a significant influence. Study evidence suggests that exposure to DDT and its breakdown product, DDE, might be associated with the risk of incident diabetes. Among Asian patients, DDT/DDE concentrations are more closely associated with diabetes. Further studies in specific regions will be considered in the future.


Assuntos
Diabetes Mellitus , Diclorodifenil Dicloroetileno , Estudos de Coortes , Estudos Transversais , DDT/toxicidade , Diabetes Mellitus/induzido quimicamente , Diabetes Mellitus/epidemiologia , Diclorodifenil Dicloroetileno/toxicidade , Humanos
6.
Environ Int ; 163: 107175, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35303528

RESUMO

BACKGROUND: Diabetes affects millions of people worldwide with a continued increase in incidence occurring within the pediatric population. The potential contribution of persistent organic pollutants (POPs) to diabetes in youth remains poorly known, especially regarding type 1 diabetes (T1D), generally the most prevalent form of diabetes in youth. OBJECTIVES: We investigated the associations between POPs and T1D in youth and studied the impacts of POPs on pancreatic ß-cell function and viability in vitro. METHODS: We used data and plasma samples from the SEARCH for Diabetes in Youth Case Control Study (SEARCH-CC). Participants were categorized as Controls, T1D with normal insulin sensitivity (T1D/IS), and T1D with insulin resistance (T1D/IR). We assessed plasma concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides and estimated the odds of T1D through multivariable logistic regression. In addition, we performed in vitro experiments with the INS-1E pancreatic ß-cells. Cells were treated with PCB-153 or p,p'-DDE at environmentally relevant doses. We measured insulin production and secretion and assessed the mRNA expression of key regulators involved in insulin synthesis (Ins1, Ins2, Pdx1, Mafa, Pcsk1/3, and Pcsk2), glucose sensing (Slc2a2 and Gck), and insulin secretion (Abcc8, Kcnj11, Cacna1d, Cacna1b, Stx1a, Snap25, and Sytl4). Finally, we assessed the effects of PCB-153 and p,p'-DDE on ß-cell viability. RESULTS: Among 442 youths, 112 were controls, 182 were classified with T1D/IS and 148 with T1D/IR. The odds ratios (OR) of T1D/IS versus controls were statistically significant for p,p'-DDE (OR 2.0, 95% confidence interval (CI) 1.0, 3.8 and 2.4, 95% CI 1.2, 5.0 for 2nd and 3rd tertiles, respectively), trans-nonachlor (OR 2.5, 95% CI 1.3, 5.0 and OR 2.3, 95% CI 1.1, 5.1 for 2nd and 3rd tertiles, respectively), and PCB-153 (OR 2.3, 95% CI 1.1, 4.6 for 3rd tertile). However, these associations were not observed in participants with T1D/IR. At an experimental level, treatment with p,p'-DDE or PCB-153, at concentrations ranging from 1 × 10-15 M to 5 × 10-6 M, impaired the ability of pancreatic ß-cells to produce and secrete insulin in response to glucose. These failures were paralleled by impaired Ins1 and Ins2 mRNA expression. In addition, among different targeted genes, PCB-153 significantly reduced Slc2a2 and Gck mRNA expression whereas p,p'-DDE mainly affected Abcc8 and Kcnj11. While treatment with PCB-153 or p,p'-DDE for 2 days did not affect ß-cell viability, longer treatment progressively killed the ß-cells. CONCLUSION: These results support a potential role of POPs in T1D etiology and demonstrate a high sensitivity of pancreatic ß-cells to POPs.


Assuntos
Diabetes Mellitus Tipo 1 , Poluentes Ambientais , Hidrocarbonetos Clorados , Resistência à Insulina , Praguicidas , Bifenilos Policlorados , Adolescente , Estudos de Casos e Controles , Criança , Diabetes Mellitus Tipo 1/epidemiologia , Diclorodifenil Dicloroetileno , Poluentes Ambientais/efeitos adversos , Glucose , Humanos , Hidrocarbonetos Clorados/análise , Insulina , Poluentes Orgânicos Persistentes , RNA Mensageiro
7.
Mol Pharm ; 19(5): 1548-1556, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35357154

RESUMO

High and sustained renal radioactivity accumulation is a major challenge in peptide-based radionuclide imaging and therapy. However, neutral endopeptidase (NEP)-based enzymatic hydrolysis to release and excrete the radioactive fragments has been proven to be an effective and promising way to reduce renal accumulation. Despite the improvement, the effect is still far from being satisfactory. To further reduce kidney uptake, we studied the relationship between the enzymatic reaction rate and the substrate concentration and came up with a combined probe strategy. Model compounds Boc-MVK-Dde and Boc-MFK-Dde were used for an in vitro enzymatic digestion study. NOTA-Exendin 4 and NOTA-MVK-Exendin 4 were labeled with 64Cu for in vivo dose-dependent micro-positron emission tomography (PET) studies. Groups 1 and 2 were injected with 0.2 and 0.8 nmol of 64Cu-NOTA-Exendin 4, respectively. Groups 3-6 were injected with 0.2, 0.8, 1.0, and 1.4 nmol of 64Cu-NOTA-MVK-Exendin 4, respectively. Groups 7 and 8 were co-injected with 0.2 nmol of 64Cu-NOTA-MVK-Exendin 4 and NOTA-MVK-PEG5K (1.3 and 2.6 nmol). The radioactivity uptakes were determined and compared within and among the groups. The in vitro cleavage study for both Boc-MVK-Dde and Boc-MFK-Dde indicated that within a certain concentration range, the enzyme digestion rate increased with increasing substrate concentration. The microPET images showed that the renal clearance could be accelerated significantly by increasing the injection dose of 64Cu-NOTA-MVK-Exendin 4, with the kidney uptakes being 60.98, 43.01, and 16.10 % ID/g at 1 h for groups 3, 4 and 5, respectively. Unfortunately, the tumor uptakes were also significantly inhibited as the injected dose of the tracer increased. However, with the co-injection of NOTA-MVK-PEG5K, the renal accumulation was significantly decreased without hampering the tumor uptake. As a result, the tumor-to-kidney ratios were significantly improved, which were 1.93, 3.47, 1.74, and 3.38 times that of group 3 at 1, 4, 24, and 48 h, respectively. The enzymatic reaction rate of NEP is dependent on the concentration of the substrates both in vitro and in vivo. The combined probe strategy developed in this study can dramatically reduce the renal accumulation of a peptide radioligand without affecting the tumor uptake, which shows great potential in peptide-based radiotheranostics.


Assuntos
Neoplasias , Radioatividade , Linhagem Celular Tumoral , Radioisótopos de Cobre , Diclorodifenil Dicloroetileno , Digestão , Exenatida/química , Compostos Heterocíclicos com 1 Anel/química , Humanos , Peptídeos/química , Tomografia por Emissão de Pósitrons/métodos
8.
Med Phys ; 49(4): 2259-2269, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35107176

RESUMO

PURPOSE: With the rising number of computed tomography (CT) examinations and the trend toward personalized medicine, patient-specific dose estimates are becoming more and more important in CT imaging. However, current approaches are often too slow or too inaccurate to be applied routinely. Therefore, we propose the so-called deep dose estimation (DDE) to provide highly accurate patient dose distributions in real time METHODS: To combine accuracy and computational performance, the DDE algorithm uses a deep convolutional neural network to predict patient dose distributions. To do so, a U-net like architecture is trained to reproduce Monte Carlo simulations from a two-channel input consisting of a CT reconstruction and a first-order dose estimate. Here, the corresponding training data were generated using CT simulations based on 45 whole-body patient scans. For each patient, simulations were performed for different anatomies (pelvis, abdomen, thorax, head), different tube voltages (80 kV, 100 kV, 120 kV), different scan trajectories (circle, spiral), and with and without bowtie filtration and tube current modulation. Similar simulations were performed using a second set of eight whole-body CT scans from the Visual Concept Extraction Challenge in Radiology (Visceral) project to generate testing data. Finally, the DDE algorithm was evaluated with respect to the generalization to different scan parameters and the accuracy of organ dose and effective dose estimates based on an external organ segmentation. RESULTS: DDE dose distributions were quantified in terms of the mean absolute percentage error (MAPE) and a gamma analysis with respect to the ground truth Monte Carlo simulation. Both measures indicate that DDE generalizes well to different scan parameters and different anatomical regions with a maximum MAPE of 6.3% and a minimum gamma passing rate of 91%. Evaluating the organ dose values for all organs listed in the International Commission on Radiological Protection (ICRP) recommendation, shows an average error of 3.1% and maximum error of 7.2% (bone surface). CONCLUSIONS: The DDE algorithm provides an efficient approach to determine highly accurate dose distributions. Being able to process a whole-body CT scan in about 1.5 s, it provides a valuable alternative to Monte Carlo simulations on a graphics processing unit (GPU). Here, the main advantage of DDE is that it can be used on top of any existing Monte Carlo code such that real-time performance can be achieved without major adjustments. Thus, DDE opens up new options not only for dosimetry but also for scan and protocol optimization.


Assuntos
Diclorodifenil Dicloroetileno , Tomografia Computadorizada por Raios X , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Doses de Radiação , Radiometria/métodos , Tomografia Computadorizada por Raios X/métodos
9.
Environ Pollut ; 301: 118979, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35150798

RESUMO

The occurrence of organic pollutants in soil is a major environmental concern. These compounds can reach the soil in different ways. Point sources, related to pesticides that are used intentionally, can be applied directly to the soil, or reach the soil indirectly due to application to the aerial parts of crops. On the other hand, non-point sources, which reach soils collaterally during irrigation and/or fertilization, or due to the proximity of plots to industrialized urban centers. Long-range transport of global organic pollutants must also be taken into account. In this study, 218 pesticides, 49 persistent organic pollutants, 37 pharmaceutical active compounds and 6 anticoagulant rodenticides were analyzed in 139 agricultural soil samples collected between 2018 and 2020 in the Macaronesia. This region comprised four inhabited archipelagos (Azores, Canary Islands, Cape Verde, and Madeira) for which agriculture is an important and traditional economic activity. To our knowledge, this is the first study on the levels of organic compound contamination of agricultural soils of the Macaronesia. As expected, the most frequently detected compounds were pesticides, mainly fungicides and insecticides. The Canary Islands presented the highest number of residues, with particularly high concentrations of DDT metabolites (p,p' DDE: 149.5 ± 473.4 ng g-1; p,p' DDD: 16.6 ± 35.6 ng g-1) and of the recently used pesticide fenbutatin oxide (302.1 ± 589.7 ng g-1). Cape Verde was the archipelago with the least contaminated soils. Very few pharmaceutical active compounds have been detected in all archipelagos (eprinomectin, fenbendazole, oxfendazole and sulfadiazine). These results highlight the need to promote soil monitoring programs and to establish maximum residue limits in soils, which currently do not exist at either continental or local level.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Poluentes do Solo , Agricultura , Diclorodifenil Dicloroetileno , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Solo/química , Poluentes do Solo/análise
10.
Environ Sci Technol ; 56(4): 2191-2203, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35089017

RESUMO

Children in low- and middle-income countries are often exposed to higher levels of chemicals and are more vulnerable to the health effects of air pollution. Little is known about the diversity, toxicity, and dynamics of airborne chemical exposures at the molecular level. We developed a workflow employing state-of-the-art wearable passive sampling technology coupled with high-resolution mass spectrometry to comprehensively measure 147 children's personal exposures to airborne chemicals in Limpopo, South Africa, as part of the Venda Health Examination of Mothers, Babies, and Their Environment (VHEMBE). 637 environmental exposures were detected, many of which have never been measured in this population; of these 50 airborne chemical exposures of concern were detected, including pesticides, plasticizers, organophosphates, dyes, combustion products, and perfumes. Biocides detected in wristbands included p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), p,p'-dichlorodiphenyldichloroethane (p,p'-DDD), p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE), propoxur, piperonyl butoxide, and triclosan. Exposures differed across the assessment period with 27% of detected chemicals observed to be either higher or lower in the wet or dry seasons.


Assuntos
Expossoma , Praguicidas , Dispositivos Eletrônicos Vestíveis , Criança , DDT , Diclorodifenil Dicloroetileno , Feminino , Humanos , Lactente , Espectrometria de Massas , Mães , África do Sul/epidemiologia
11.
Environ Sci Pollut Res Int ; 29(19): 28402-28413, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34988801

RESUMO

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) remain a global concern in both developed and developing countries. Given that diet constitutes the major route of exposure to these pollutants, the objective of the current study is to investigate PCBs and OCPs serum levels in relation to dietary quality indices in a sample of Lebanese adults. Sociodemographic, nutritional, and anthropometric data were obtained from 302 participants in face-to-face interviews. Nutritional intakes from a previously validated quantitative 164-item food frequency questionnaire were used to calculate six a priori dietary indices: Healthy Eating Index (HEI-2015), alternate Healthy Eating Index (aHEI), Diet Quality Index-International (DQI-I), Mediterranean Diet Quality Index (Med-DQI), Med-DQIf, Mediterranean Diet Scale (MDS), and Mediterranean Diet Score (MedDietScore). Serum levels of six indicator PCBs (PCBs 28, 52, 101, 138, 153, 180) and four OCPs (HCB, ß-HCH, DDT, and DDE) were investigated in relation to diet quality indices. Individuals with a higher adherence to the HEI-2015 and to the Mediterranean diet assessed by the Med-DQI/Med-DQIf displayed increased levels of OCPs (HCB, ßHCH, DDT, and DDE). An inverted U-shaped association was observed between DQI-I and PCBs serum levels (PCBs 138, 153, 180, and Æ©PCBs). This is the first study in the Middle East and North Africa region to investigate the association between POPs serum levels and a substantial number of a priori dietary indices. The impact of different food combinations and nutrient interactions on pollutants body burden and toxicity remains to be established in future studies.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Adulto , DDT/análise , Diclorodifenil Dicloroetileno/análise , Dieta , Monitoramento Ambiental , Poluentes Ambientais/análise , Hexaclorobenzeno/análise , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise
12.
Environ Sci Pollut Res Int ; 29(23): 34164-34173, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35034314

RESUMO

Exposure to mercury (Hg) and pesticides (o.p'DDT, p.p'DDT, o.p'DDE, and p.p'DDE) in the Amazon through eating fish is of concern due to the large participation of this food in the diet of traditional fishing communities. The aim of this study was to evaluate the estimated daily intake (EDI) and the incremental lifetime cancer risk associated with Hg and o.p'DDT, p.p'DDT, o.p'DDE, and p.p'DDE in an Amazonian community. The results showed that for Hg, the EDI from carnivorous and detritivorous fish had the highest values, while for pesticides, the EDI from detritivorous fish intake had the highest value. The incremental lifetime cancer risk was below the permitted limit. A recommendation for controlling the high risk of exposure includes the reduction of detritivorous fish ingestion and/or replacement with herbivorous fish, which had lower EDI. We highlight the importance of investigating the human dietary patterns when estimating risk of exposure to Hg and pesticides.


Assuntos
Mercúrio , Resíduos de Praguicidas , Animais , DDT , Diclorodifenil Dicloroetileno , Dieta , Peixes , Resíduos de Praguicidas/análise
13.
Sci Total Environ ; 821: 153447, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35092765

RESUMO

The broad-spectrum insecticide p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) has been banned in most countries since the 1970s on account of its environmental persistence as well as the high biomagnification of its major metabolite 1,1-dichloro-2,2-bis(4-chorophenyl)ethylene (p,p'-DDE). However, the information on the bioaccumulation and behavior of p,p'-DDTs in aquatic organisms is lacking. In this study, all 6 DDT isomers were detected in biota from the food web of the Liaodong Bay, China, and the total concentrations of DDT isomers in Chinese anchovy (Thrissa kammalensis) and Japanese Spanish mackerel (Scomberomrus niphonius) were 223 ± 42 ng/g ww and 242 ± 70 ng/g ww, respectively. In biota, o,p'-DDD dominated among the o,p'-isomers (80.5 ± 17.3%), while p,p'-DDE dominated among the p,p'-isomers (61.8 ± 15.2%). Contrastingly, sediment from the Liaodong Bay contained similar proportions of o,p'-DDT and p,p'-DDTs, suggesting an isomer-specific metabolism of the compounds in biota. A well-controlled laboratory exposure experiment with Japanese medaka (Oryzias latipes) demonstrated that o,p'-DDT was more difficult to metabolize to o,p'-DDE compared with that of p,p'-DDT. Significantly positive regressions were found between trophic levels and lipid equivalent concentrations for both o,p'-DDT and o,p'-DDD, and the trophic magnification factors (TMFs) were estimated as 12.3 and 9.12 (p < 0.05), respectively. The TMFs of o,p'-DDT and o,p'-DDD in the aquatic food web were higher than p,p'-DDT (7.76), p,p'-DDD (4.17), and p,p'-DDE (3.39), which may be explained by the isomer-specific metabolism differences in biota.


Assuntos
DDT , Poluentes Químicos da Água , China , DDT/análise , Diclorodifenil Dicloroetileno/análise , Cadeia Alimentar , Poluentes Químicos da Água/análise
14.
Environ Res ; 206: 112431, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-34848208

RESUMO

It is important to identify the factors that influence the prevalence of disinhibitory behaviors, as tobacco and alcohol use in adolescence is a strong predictor of continued use and substance abuse into adulthood. Organochlorine pesticides (OCPs) are persistent organic pollutants that pose a potential risk to the developing fetus and offspring long-term health. We examined associations between prenatal exposure OCPs and their metabolites (i.e., p,p'-DDT, p,p'-DDE, o,p'-DDT, oxychlordane, and hexachlorobenzene (HCB)), both as a mixture and single compounds, and alcohol consumption and smoking at adolescence in a sample (n = 554) from the Child Health and Development Studies prospective birth cohort. Bayesian Kernel Machine Regression demonstrated a trend of higher risk of alcohol use and smoking with higher quartile mixture levels. Single-component analysis showed increased odds of smoking and drinking with increases in lipid-adjusted p,p'-DDE serum levels (aOR = 2.06, 95% CI 0.99-4.31, p = 0.05, per natural log unit increase). We found significant effect modification in these associations by sex with higher p,p'-DDT serum levels (aOR = 0.26, 95% CI 0.09-0.076, p = 0.01, per natural log unit increase) was associated with lower odds of smoking and drinking in female adolescents, while higher p,p'-DDE serum levels (aOR = 2.98, 95% CI 1.04-8.51, p = 0.04, per natural log unit increase) was associated with higher odds of the outcomes. Results of the mutually adjusted model were not significant for male adolescents. Further research to understand reasons for these sex-differences are warranted.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Efeitos Tardios da Exposição Pré-Natal , Adolescente , Adulto , Teorema de Bayes , Criança , DDT/análise , Diclorodifenil Dicloroetileno , Comportamento de Ingestão de Líquido , Feminino , Humanos , Masculino , Praguicidas/análise , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Estudos Prospectivos , Fumar/epidemiologia
15.
Sci Total Environ ; 818: 151814, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-34813814

RESUMO

While the secondary metabolites of DDT such as 2,2-bis(chlorophenyl)-1-chloroethylene (DDMU) and 2,2-bis(chlorophenyl)methane (DDM) have been detected in the environment for several decades, knowledge is extremely limited on their bioaccumulation characteristics. Here, we reported the bioaccumulation and maternal transfer of p,p'-DDMU and p,p'-DDM in two wild fishes, i.e., the northern snakehead (Channa argus) and crucian carp (Carassius auratus), from a DDT contaminated site in South China. The hepatic concentrations of p,p'-DDMU and p,p'-DDM in the fish were up to 549 and 893 ng/g lipid weight, contributing 5.3% and 3.2% in average to ΣDDXs (the sum concentrations of DDT and its 6 metabolites), respectively. The residues of p,p'-DDMU and p,p'-DDM in the fish exhibited interspecific and intraspecific variations, resulting from the differences in lipid content, sex, and body sizes (length and mass) between or within species. Both p,p'-DDMU and p,p'-DDM were consistently detected in the fish eggs, demonstrating their maternal transfer in female fish. The mean eggs to liver lipid-normalized concentration (E/L) ratios of p,p'-DDMU and p,p'-DDM were 0.98 and 1.77 in the northern snakehead, 0.35 and 0.01 in crucian carp, respectively; which were comparable to or even exceeded those of DDT and its major metabolites calculated in the same individual. Statistical analyses of the data showed that the E/L ratios were positively correlated with body sizes of the fish, but negatively correlated with the hepatic concentrations of p,p'-DDMU and p,p'-DDM in females; suggesting the influences of fish sizes and the mother body residues on their maternal transfer efficiencies.


Assuntos
DDT , Peixes , Animais , Bioacumulação , China , DDT/análise , Diclorodifenil Dicloroetileno/análise , Feminino , Peixes/metabolismo
16.
Pediatr Res ; 91(3): 690-698, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33824444

RESUMO

BACKGROUND: Potentially harmful effects of persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) on prenatal development and the endocrine system have been controversially discussed. METHODS: Working with a German cohort of 324 pregnant women, we assessed POP levels and used robust linear regression models to determine potential associations between maternal POP concentrations and pre- and postnatal development in the children, as well as the thyroid hormone status of the mother and child. RESULTS: Maternal p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and most measured PCBs positively correlated with postnatal weight gain. We detected no correlation between newborn birth weight and head circumference, respectively, and maternal PCB and p,p'-DDE serum levels, while body length at birth was negatively associated with the maternal serum concentration of PCB 183. Maternal p,p'-DDE and nearly all PCB serum levels showed a negative correlation with maternal free triiodothyronine (FT3). p,p'-DDE and PCB 74 and 118 were negatively associated with maternal thyroid-stimulating hormone levels. In addition, we identified significant associations between maternal POP levels and thyroid hormone parameters of the child. CONCLUSIONS: These results indicate that POP exposure likely affects different aspects of pre- and postnatal development and impacts the thyroid hormone status of both mother and child. IMPACT: Pregnant women in a German cohort display a substantial accumulation of POPs. Body mass index and age influence maternal serum POP levels. Maternal POP levels show correlations with the child's length at birth and weight gain, and FT3 levels in the mother and child. Our data provide additional evidence for the potentially harmful influence of POPs. Our data indicate that POPs influence pre- and postnatal development.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Criança , Desenvolvimento Infantil , Diclorodifenil Dicloroetileno/efeitos adversos , Poluentes Ambientais/efeitos adversos , Feminino , Humanos , Recém-Nascido , Exposição Materna/efeitos adversos , Poluentes Orgânicos Persistentes , Bifenilos Policlorados/efeitos adversos , Gravidez , Gestantes , Hormônios Tireóideos , Ganho de Peso
17.
Environ Res ; 203: 111767, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34391732

RESUMO

Persistent organic pollutants (POPs), known as common environmental pollutants, which have adverse effects on neurobehavioral development, are widely applied in industry and agriculture. However, evidence about neurodevelopmental toxicity of POPs in humans is limited. This study aimed to explore the relationship between prenatal exposure to POPs and birth outcome of the newborn including birth length, weight, and head circumference. In this study, 1522 mother-child pairs were included in this study and cord blood samples were collected, which were detected to determine exposure level of 37 POPs in total. After delivery, the neonatal anthropometric indices detection (birth length, weight, and head circumference) was performed. According to the multivariate linear regression, the newborn with high detection rates (≥75 percentile) of hexachlorobenzene (HCB), beta-hexachlorocyclohexane (ß-HCH), p,p'-dichlorodiphenyl dichloroethylene (p,p'-DDE) in the umbilical cord blood were demonstrated negative relationship with birth head circumference after adjusting for confounding factors, but not related with birth length and weight. After confirming that there was a nonlinear relationship between HCB and birth head circumference based on sex stratification through the generalized additive model (GAM), further two-piecewise linear regression model was conducted to explore the saturation threshold effect between HCB and birth head circumference, which showed cord serum HCB concentration greater than 0.5 µg/L was negatively associated with birth head circumference in girls. Our study provided evidence for the adverse influence of HCB, ß-HCH and p,p'-DDE exposure during pregnancy on the birth head circumference of offspring. Although HCB induced reduction of birth head circumference was found in girls, the mechanism of gender difference remained unclear. Further studies are needed to explore the effect of POPs on the growth and development of offspring based on in vivo or in vitro experimental models.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Efeitos Tardios da Exposição Pré-Natal , China/epidemiologia , Diclorodifenil Dicloroetileno , Poluentes Ambientais/toxicidade , Feminino , Humanos , Exposição Materna/efeitos adversos , Relações Mãe-Filho , Poluentes Orgânicos Persistentes , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/epidemiologia
18.
Gen Comp Endocrinol ; 317: 113963, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902316

RESUMO

Chronic exposure to low doses of anthropogenic chemicals in the environment continues to be a major health issue. Due to concerns about the effects in humans and wildlife, use of persistent organic pollutants, such as dichlorodiphenyltrichloroethane (DDT), is prohibited. However, their ubiquitous nature and persistence allows them to remain in the environment at low levels for decades. Dichlorodiphenyldichloroethylene (DDE) is the most persistent metabolite of DDT and has been shown to cause hepatotoxicity, nephrotoxicity, hormonal disorders, and induce oxidative stress in many organisms. Although the effects of acute exposure to DDT and its metabolite DDE have been extensively studied, the chronic effects of sub-lethal DDE exposure at levels comparable to those found in the environment have not been well documented. Long-Evans male rats were used to determine the effect of relatively chronic and short term DDE (doses ranged from 0.001 to 100 µg/L) exposure on endocrine function and oxidative stress at different developmental time points. We found that circulating serum testosterone (T) levels were significantly decreased and T secretion in testicular explants were significantly influenced in a dose dependent manner in both pre-pubertal and pubertal male rats after DDE exposure, with pubertal rats being the most affected contrary to our original prediction. Additionally, exposure to DDE increased expression of protein oxidation indicating a possible increase in cellular damage caused by oxidative stress. This study suggests that chronic exposures to environmentally relevant levels of DDE affected testicular function and decreased T secretion with implications for reproductive capacity.


Assuntos
Diclorodifenil Dicloroetileno , Estresse Oxidativo , Animais , Diclorodifenil Dicloroetileno/toxicidade , Hormônios , Masculino , Ratos , Ratos Long-Evans , Esteroides
19.
Int J Hyg Environ Health ; 239: 113865, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34700204

RESUMO

BACKGROUND: Experimental evidence suggests that p,p'-DDE might be involved in the development of diabetes and hypertension (HTN); however, the evidence in humans is inconclusive. OBJECTIVE: To summarize the epidemiological evidence for the association of p,p'-DDT exposure and its breakdown products with the risk of diabetes and HTN from prospective studies. METHODS: We performed a systematic review and meta-analysis based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Eligible studies (prospective) were search in PubMed, Web of Science, EBSCO, and SciELO databases (July 11, 2020). Different search algorithms were used for diabetes and HTN. Pooled odds ratios (ORs) were estimated from meta-analysis with random effects for each exposure and outcome. RESULTS: A total of 23 prospective studies were included in this review, 16 assessed diabetes and seven HTN; very few measured p,p'-DDT. Exposure to p,p'-DDE was associated with a slightly increased risk of type 2 diabetes (T2D) (pooled OR = 1.44; 95%CI: 1.00, 2.07; p = 0.049) and HTN (pooled OR = 1.21; 95%CI: 1.07, 1.38). Dose-response meta-analysis suggested a non-linear relation between p,p'-DDE and T2D. Exposure to p,p'-DDE was not associated with gestational diabetes (pooled OR = 1.01; 95%CI: 0.94, 1.09); similarly, p,p'-DDT was not associated with T2D (pooled OR = 1.03; 95%CI: 0.79, 1.35). CONCLUSIONS: Evidence from prospective studies suggests that exposure to p,p'-DDE, the main breakdown product of p,p'-DDT, might increase the risk of developing T2D; such increase may be apparent only at low levels. Exposure to p,p'-DDE may also increase the risk of having HTN; however, further evidence is required.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Praguicidas , DDT , Diabetes Mellitus Tipo 2/epidemiologia , Diclorodifenil Dicloroetileno , Humanos , Hipertensão/epidemiologia , Estudos Prospectivos
20.
Lupus ; 30(14): 2204-2212, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34677112

RESUMO

Organochlorines (OCs) are groups of highly toxic pesticides with known immunotoxicity. The present work aimed to study the potential association between serum residues of OCs and the risk of developing systemic lupus erythematosus (SLE) as well as correlating to the clinical-laboratory manifestations in a sample of Egyptian SLE patients. A cross-sectional study was conducted on 132 patients environmentally exposed to OCs. Patients were diagnosed as SLE based on the American College of Rheumatology (ACR) revised criteria. Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2K) score was calculated to stratify the disease severity. Blood and urine samples were collected to measure the levels of OCs, serological markers, and urinary protein. The most frequently detected OCs were p,p'-DDE; lindane; and hexachlorobenzene (HCB). The risk of developing SLE was significantly associated with detected p,p'-DDE and HCB (B value 7.704 and 14.33, respectively). Hexachlorobenzene, in addition, was significantly associated with increased SLEDAI-2K score and polycythemia. Lindane was significantly associated with hypocomplementemia, cardiac manifestations of SLE, anemia, and leucopenia. In conclusion, the detected OCs p,p'-DDE and HCB are associated with increased risk of SLE in Egyptian patients and correlates to the manifestations of disease severity.


Assuntos
Diclorodifenil Dicloroetileno/química , Hexaclorobenzeno/química , Hexaclorocicloexano/química , Hidrocarbonetos Clorados , Lúpus Eritematoso Sistêmico , Estudos Transversais , Humanos , Lúpus Eritematoso Sistêmico/induzido quimicamente , Índice de Gravidade de Doença
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