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1.
Environ Geochem Health ; 45(2): 333-342, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35246781

RESUMO

Residents and advocacy groups began voicing concerns over the environmental quality located in the neighborhoods of Kashmere Gardens, Fifth Ward, and Denver Harbor in Houston, TX, following the confirmation of a cancer cluster in 2019 and another in 2021. These neighborhoods are in close proximity to a railyard and former wood treatment plant known to have utilized coal tar creosote and contain polycyclic aromatic hydrocarbons (PAHs). This research took core soil samples in September and October 2020 from 46 sites to assess for the presence and concentration of the U.S. Environmental Protection Agency's (USEPA) 7 Carcinogenic PAHs. Results showed the cumulative concentration of these PAHs in each sample was variable with a range of 13,767 ng/g to 328 ng/g and a mean of 2,517.2 ng/g ± 3122. A regional soil screening evaluation revealed that 40 of the 46 soil samples were in excess of the USEPAs most conservative screening levels of 1.0 × 10-6 increased cancer risk, but none exceeding levels considered actionable for remediation. This study is a fundamental first step for quantifying the environmental pollutants in this minority-majority community. Findings revealed a low risk of cancer risk based on current PAH concentrations alone but cannot assess contributions from other contaminants or from past, possibly higher, levels of contamination. Further research is needed to identify the potential casual pathways of the observed cancer cluster and to explore possible remediation needs.


Assuntos
Neoplasias , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Humanos , Solo , Carvão Mineral/análise , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Texas/epidemiologia , Justiça Ambiental , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Medição de Risco , China
2.
Environ Res ; 204(Pt A): 111893, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34419473

RESUMO

BACKGROUND: Given the time and monetary costs associated with traditional analytical chemistry, there remains a need to rapidly characterize environmental samples for priority analysis, especially within disaster research response (DR2). As PAHs are both ubiquitous and occur as complex mixtures at many National Priority List sites, these compounds are of interest for post-disaster exposures. OBJECTIVE: This study tests the field application of the KinExA Inline Biosensor in Galveston Bay and the Houston Ship Channel (GB/HSC) and in the Elizabeth River, characterizing the PAH profiles of these region's soils and sediments. To our knowledge, this is the first application of the biosensor to include soils. METHODS: The biosensor enables calculation of total free PAHs in porewater (C free), which is confirmed through gas chromatography-mass spectrometry (GC-MS) analysis. To determine potential risk of the collected soils the United States Environmental Protection (USEPA) Agency's Regional Screening Level (RSL) Calculator is used along with the USEPA Region 4 Ecological Screening Values (R4-ESV) and Refined Screening Values (R4-RSV). RESULTS: Based on GC-MS results, all samples had PAH-related hazard indices below 1, indicating low noncarcinogenic risks, but some samples exceeded screening levels for PAH-associated cancer risks. Combining biosensor-based C free with Total Organic Carbon yields predictions highly correlated (r > 0.5) both with total PAH concentrations as well as with hazard indices and cancer risks. Additionally, several individual parent PAH concentrations in both the GB/HSC and Elizabeth River sediments exceeded the R4- ESV and R4-RSV values, indicating a need for follow-up sediment studies. CONCLUSIONS: The resulting data support the utility of the biosensor for future DR2 efforts to characterize PAH contamination, enabling preliminary PAH exposure risk screening to aid in prioritization of environmental sample analysis.


Assuntos
Técnicas Biossensoriais , Desastres , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise
3.
Fuel (Lond) ; 3172022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35250041

RESUMO

In the process of registration of substances of Unknown or Variable Composition, Complex Reaction Products or Biological Materials (UVCBs), information sufficient to enable substance identification must be provided. Substance identification for UVCBs formed through petroleum refining is particularly challenging due to their chemical complexity, as well as variability in refining process conditions and composition of the feedstocks. This study aimed to characterize compositional variability of petroleum UVCBs both within and across product categories. We utilized ion mobility spectrometry (IMS)-MS as a technique to evaluate detailed chemical composition of independent production cycle-derived samples of 6 petroleum products from 3 manufacturing categories (heavy aromatic, hydrotreated light paraffinic, and hydrotreated heavy paraffinic). Atmospheric pressure photoionization and drift tube IMS-MS were used to identify structurally related compounds and quantified between- and within-product variability. In addition, we determined both individual molecules and hydrocarbon blocks that were most variable in samples from different production cycles. We found that detailed chemical compositional data on petroleum UVCBs obtained from IMS-MS can provide the information necessary for hazard and risk characterization in terms of quantifying the variability of the products in a manufacturing category, as well as in subsequent production cycles of the same product.

4.
Environ Monit Assess ; 194(5): 330, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35384492

RESUMO

Although urban community food gardens have the capacity to strengthen and support neighborhoods in need, the benefits of such operations must be considered in tandem with the potential risks associated with urban environmental contamination. Therefore, research is needed to characterize existing community gardens in urban areas. In the present study, a survey of Houston, TX, community gardeners (N = 20) was conducted to better understand their risk-based knowledge and perceptions, current gardening practices, and willingness to implement risk mitigation measures. Soil samples collected from the beds (N = 22) and surrounding grounds (N = 24) of existing community garden sites in Houston, TX, were screened for trace and heavy metals using X-ray fluorescence spectrometry. The survey indicated that community gardeners had few concerns with regard to potential soilborne hazards and were generally willing to use diverse strategies to reduce potential hazards related to garden soil contamination. Ground and garden bed soil collected from community gardens were found to have excess concentrations of arsenic compared to federal health screening limits. The information provided here provides insight into possible discordance between community gardening risk perception and contamination risk that could be addressed through outreach, engagement, and remediation approaches.


Assuntos
Jardins , Poluentes do Solo , Monitoramento Ambiental , Jardinagem , Solo/química , Poluentes do Solo/análise , Texas
5.
Molecules ; 26(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33671906

RESUMO

Alternaria toxins are emerging mycotoxins whose regulation and standardization are in progress by the European Commission and the European Committee for Standardization. This paper describes a dilute and shoot approach to determine five Alternaria toxins in selected food samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The strategy involves sample extraction with acidified aqueous methanol, followed by a solvent change accomplished via sample evaporation and reconstitution. The quantification is based on isotope dilution, applying all corresponding isotopically labeled internal standards to compensate possible matrix effects of the analysis. The main advantages of the present method over other existing methods includes simple and effective sample preparation, as well as detection with high sensitivity. The five-fold sample dilution can decrease matrix effects, which were evaluated with both external and internal standard methods. The results demonstrated a limit of quantification lower than 1.0 µg/kg for all five analytes for the first time. The newly presented method showed acceptable accuracy (52.7-111%) when analyzing naturally contaminated and spiked standard samples at the described levels. The method was validated for tomato-based and flour samples (wheat, rye, and maize). The absolute recovery ranged from 66.7% to 91.6% (RSD < 10%). The developed method could be an alternative approach for those laboratories that exclude sample cleanup and pre-concentration of state-of-the-art instruments with enhanced sensitivity.


Assuntos
Alternaria/química , Farinha/análise , Marcação por Isótopo/métodos , Espectrometria de Massas/métodos , Solanum lycopersicum/química , Toxinas Biológicas/análise , Cromatografia Líquida , Controle de Qualidade , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
6.
J Environ Sci (China) ; 100: 131-143, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33279026

RESUMO

The widespread use of pesticides has resulted in detectable residues throughout the environment, sometimes at concentrations well above regulatory limits. Therefore, the development of safe, effective, field-practical, and economically feasible strategies to mitigate the effects of pesticides is warranted. Glyphosate is an organophosphorus herbicide that is degraded to aminomethylphosphonic acid (AMPA), a toxic and persistent metabolite that can accumulate in soil and sediment and translocate to plants. In this study, we investigated the binding efficacy of activated carbon (AC) and calcium montmorillonite (CM) clay to decrease AMPA bioavailability from soil and AMPA translocation to plants. Adsorption isotherms and thermodynamic studies on AC and CM were conducted and showed tight binding (enthalpy values >-20 kJ/mol) for AMPA with high capacities (0.25 mol/kg and 0.38 mol/kg, respectively), based on derivations from the Langmuir model. A hydra assay was utilized to indicate toxicity of AMPA and the inclusion of 1% AC and CM both resulted in 90% protection of the hydra (**p ≤ 0.01). Further studies in glyphosate-contaminated soil showed that AC and CM significantly reduced AMPA bioavailability by 53% and 44%, respectively. Results in genetically modified (GM) corn showed a conversion of glyphosate to AMPA in roots and sprouts over a 10-day exposure duration. Inclusion of AC and CM reduced AMPA residues in roots and sprouts by 47%-61%. These studies collectively indicate that AC and CM are effective sorbents for AMPA and could be used to reduce AMPA bioavailability from soil and AMPA residues in GM corn plants.


Assuntos
Herbicidas , Poluentes do Solo , Bentonita , Disponibilidade Biológica , Cálcio , Carvão Vegetal , Argila , Herbicidas/análise , Organofosfonatos , Solo , Poluentes do Solo/análise , Zea mays/genética , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico
7.
Environ Sci Technol ; 52(19): 11319-11327, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30187746

RESUMO

This paper presents an accelerated ferrate(VI) (FeVIO42-, FeVI) oxidation of contaminants in 30 s by adding one-electron and two-electron transfer reductants (R(1) and R(2)). An addition of R(2) (e.g., NH2OH, AsIII, SeIV, PIII, and NO2-, and S2O32-) results in FeIV initially, while FeV is generated with the addition of R(1) (e.g., SO32-). R(2) additives, except S2O32-, show the enhanced oxidation of 20-40% of target contaminant, trimethoprim (TMP). Comparatively, enhanced oxidation of TMP was up to 100% with the addition of R(1) to FeVI. Interestingly, addition of S2O32- (i.e., R(2)) also achieves the enhanced oxidation to 100%. Removal efficiency of TMP depends on the molar ratio ([R(1)]:[FeVI] or [R(2)]:[FeVI]). Most of the reductants have the highest removal at molar ratio of ∼0.125. A FeVI-S2O32- system also oxidizes rapidly a wide range of organic contaminants (pharmaceuticals, pesticides, artificial sweetener, and X-ray contrast media) in water and real water matrices. FeV and FeIV as the oxidative species in the FeVI-S2O32--contaminant system are elucidated by determining removal of contaminants in oxygenated and deoxygenated water, applying probing agent, and identifying oxidized products of TMP and sulfadimethoxine (SDM) by FeVI-S2O32- systems. Significantly, elimination of SO2 from sulfonamide (i.e., SDM) is observed for the first time.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Ferro , Cinética , Oxirredução , Trimetoprima
8.
Environ Sci Technol ; 52(2): 684-691, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29236483

RESUMO

We applied a mathematical model to data from experimental column studies to understand the dynamics of successful and unsuccessful reductive dechlorination of chlorinated ethenes in groundwater under different flow conditions. In laboratory column experiments (reported previously), it was observed that complete dechlorination of cis-dichloroethene to ethene was sustained at high flow velocity (0.51 m/d), but that dechlorination failed at medium or low flow velocity (0.080 or 0.036 m/d). The mathematical model applied here accounts for transport of chlorinated ethenes in flowing groundwater, mass transfer of chlorinated ethenes between mobile groundwater and stationary biofilms, and diffusion and biodegradation within the biofilms. Monod kinetics with competitive inhibition are used to describe biodegradation. Nearly all parameters needed to solve the model are estimated independently from batch and nonreactive transport experiments. Comparing the model predictions to the experimental results permits the evaluation of three hypothesized biological limitations: insufficient supply of electron donor, decay of dechlorinators' biomass, and reduction in bacterial metabolism rates. Any of these three limitations are able to adequately describe observed experimental data, but insufficient supply of electron donor is the most plausible explanation for failure of dechlorination. Therefore, an important conclusion of this investigation is that insufficient hydrogen production occurs if groundwater flow is too slow to provide adequate flux of electron donor. Model simulations were in good agreement with experimental results for both successful and unsuccessful dechlorination, suggesting the model is a valid tool for describing transport and reductive dechlorination. An implication of our findings is that in engineered or natural bioremediation of chloroethene-contaminated groundwater, not only must the proper dechlorinating organisms be present, but also proper groundwater flow conditions must be maintained or else dechlorination may fail.


Assuntos
Água Subterrânea , Cloreto de Vinil , Poluentes Químicos da Água , Biodegradação Ambiental , Halogenação , Porosidade
9.
J Pharmacol Exp Ther ; 361(1): 17-28, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28148637

RESUMO

Lifestyle factors and chronic pathologic states are important contributors to interindividual variability in susceptibility to xenobiotic-induced toxicity. Nonalcoholic fatty liver disease (NAFLD) is an increasingly prevalent condition that can dramatically affect chemical metabolism. We examined the effect of NAFLD on toxicokinetics of tetrachloroethylene (PERC), a ubiquitous environmental contaminant that requires metabolic activation to induce adverse health effects. Mice (C57Bl/6J, male) were fed a low-fat diet (LFD), high-fat diet (HFD), or methionine/folate/choline-deficient diet (MCD) to model a healthy liver, steatosis, or nonalcoholic steatohepatitis (NASH), respectively. After 8 weeks, mice were orally administered a single dose of PERC (300 mg/kg) or vehicle (aqueous Alkamuls-EL620) and euthanized at various time points (1-36 hours). Levels of PERC and its metabolites were measured in blood/serum, liver, and fat. Effects of diets on liver gene expression and tissue:air partition coefficients were evaluated. We found that hepatic levels of PERC were 6- and 7.6-fold higher in HFD- and MCD-fed mice compared with LFD-fed mice; this was associated with an increased PERC liver:blood partition coefficient. Liver and serum Cmax for trichloroacetate (TCA) was lower in MCD-fed mice; however, hepatic clearance of TCA was profoundly reduced by HFD or MCD feeding, leading to TCA accumulation. Hepatic mRNA/protein expression and ex vivo activity assays revealed decreased xenobiotic metabolism in HFD- and MCD-, compared with LFD-fed, groups. In conclusion, experimental NAFLD was associated with modulation of xenobiotic disposition and metabolism and increased hepatic exposure to PERC and TCA. Underlying NAFLD may be an important susceptibility factor for PERC-associated hepatotoxicity.


Assuntos
Poluentes Ambientais/farmacocinética , Poluentes Ambientais/toxicidade , Hepatopatia Gordurosa não Alcoólica/metabolismo , Tetracloroetileno/farmacocinética , Tetracloroetileno/toxicidade , Animais , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Toxicocinética
10.
J Toxicol Environ Health A ; 80(9): 513-524, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28696834

RESUMO

Tetrachloroethylene (perchloroethylene; PERC) is a high-production volume chemical and ubiquitous environmental contaminant that is hazardous to human health. Toxicity attributed to PERC is mediated through oxidative and glutathione (GSH) conjugation metabolites. The conjugation of PERC by glutathione-s-transferase to generate S-(1,2,2-trichlorovinyl) glutathione (TCVG), which is subsequently metabolized to form S-(1,2,2-trichlorovinyl)-L-cysteine (TCVC) is of special importance to human health. Specifically, TCVC may be metabolized to N-acetyl-S-(1,2,2-trichlorovinyl)-L-cysteine (NAcTCVC) which is excreted through urine, or to electrophilic metabolites that are nephrotoxic and mutagenic. Little is known regarding toxicokinetics of TCVG, TCVC, and NAcTCVC as analytical methods for simultaneous determination of these metabolites in tissues have not yet been reported. Hence, an ultra-high-performance liquid chromatography electrospray ionization tandem mass spectrometry-based method was developed for analysis of TCVG, TCVC, and NAcTCVC in liver, kidneys, serum, and urine. The method is rapid, sensitive, robust, and selective for detection all three analytes in every tissue examined, with limits of detection (LOD) ranging from 1.8 to 68.2 femtomoles on column, depending on the analyte and tissue matrix. This method was applied to quantify levels of TCVG, TCVC, and NAcTCVC in tissues from mice treated with PERC (10 to 1000 mg/kg, orally) with limits of quantitation (LOQ) of 1-2.5 pmol/g in liver, 1-10 pmol/g in kidney, 1-2.5 pmol/ml in serum, and 2.5-5 pmol/ml in urine. This method is useful for further characterization of the GSH conjugative pathway of PERC in vivo and improved understanding of PERC toxicity.


Assuntos
Acetilcisteína/metabolismo , Cromatografia Líquida de Alta Pressão , Glutationa/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Tetracloroetileno/metabolismo , Acetilcisteína/sangue , Acetilcisteína/urina , Animais , Glutationa/sangue , Glutationa/urina , Camundongos , Tetracloroetileno/sangue , Tetracloroetileno/urina
11.
Water Environ Res ; 89(6): 508-518, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28545602

RESUMO

The authors used fecal sterol analysis to determine the potential contribution of E. coli from heronries to waterbodies in east-central Texas. They analyzed E. coli and fecal sterol concentrations in samples from four heronries during the breeding seasons in 2011-2013. The highest E. coli concentrations were in water samples from the two largest heronries established directly over water. The main sterols in fecal samples were cholesterol and stigmasterol, and in water, cholesterol, coprostanol, and cholestanol. Total sterols ranged 979 to 5838 ng/g dry weight in fecal samples, and 13 to 600 ng/L in water samples. There was a positive correlation between E. coli and the sum of bird sterols in water exposed directly to fecal deposition, but not in water surrounding the heronries. The authors found a strong association between E. coli and stigmasterol, suggesting that the presence of stigmasterol in water could be used for predicting E. coli sources from heronries nesting close to waterbodies.


Assuntos
Aves/fisiologia , Escherichia coli , Comportamento de Nidação , Esteróis/química , Microbiologia da Água , Qualidade da Água , Animais , Fezes/química , Análise de Componente Principal , Estações do Ano , Texas , Fatores de Tempo , Áreas Alagadas
12.
Am J Epidemiol ; 183(7): 634-42, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26953287

RESUMO

Prenatal exposure to nitrosatable drugs, including secondary or tertiary amines, has been associated with preterm birth. Associations may be accentuated by higher intakes of dietary nitrites because of the increased formation of N-nitroso compounds. Using data from mothers of babies without major birth defects (controls) from the National Birth Defects Prevention Study, we examined the relationship between nitrosatable drug exposure in conjunction with dietary nitrite intake and preterm birth among 496 mothers of preterm infants and 5,398 mothers with full-term deliveries in 1997-2005. A protective association was observed with a high intake of plant nitrites (adjusted hazard ratio (AHR) = 0.72, 95% confidence interval (CI): 0.53, 0.97). Secondary amines in conjunction with high nitrite intake were associated with preterm birth during the first (AHR = 1.84, 95% CI: 1.14, 2.98), second (AHR = 1.89, 95% CI: 1.17, 3.07), and third (AHR = 2.00, 95% CI: 1.22, 3.29) trimesters. The adjusted hazard ratios for tertiary amine use in the third trimester by increasing tertiles of nitrite intake were 0.67 (95% CI: 0.35, 1.31), 1.25 (95% CI: 0.71, 2.19), and 2.02 (95% CI: 1.17, 3.49). Prenatal exposure to nitrosatable drugs, particularly secondary and tertiary amines, in conjunction with higher levels of dietary nitrite intake may increase the risk of preterm birth.


Assuntos
Nitritos/efeitos adversos , Compostos Nitrosos/efeitos adversos , Nascimento Prematuro/epidemiologia , Efeitos Tardios da Exposição Pré-Natal , Adolescente , Adulto , Estudos de Casos e Controles , Dieta/efeitos adversos , Dieta/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Nascimento Prematuro/etiologia , Estados Unidos/epidemiologia , Adulto Jovem
13.
Genet Med ; 18(12): 1206-1213, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27124787

RESUMO

PURPOSE: The College of American Pathologists offers blinded proficiency testing (PT) for laboratories performing HFE genetic tests for hereditary hemochromatosis (common C282Y and H63D variants). This study used 10 years of PT data to determine laboratory performance for HFE analytical genotyping and clinical interpretation. METHODS: Laboratories were graded for accuracy of genotype determination (six possible C282Y/H63D genotypes) and clinical interpretation regarding whether the genotype was likely to have contributed to iron overload in a hypothetical patient. RESULTS: The analytical genotyping error rate was low (0.73%) in 7,663 results (from 257 unique laboratories). Genotyping errors were significantly higher in C282Y heterozygous, H63D homozygous, and C282Y homozygous samples, in non-American laboratories, and in laboratories with lower testing volume. Analytical sensitivity and specificity were >98.5 and >99.5%. The interpretive error rate (4.3%) was higher than the genotyping error rate, with two problematic genotypes (C282Y heterozygous and H63D homozygous) accounting for 77% of total interpretive errors. There was a time-dependent improvement in the interpretation of the clinical significance of HFE genotypes. CONCLUSIONS: HFE molecular genetic testing, performed by non-US Food and Drug Administration-approved laboratory-developed tests, demonstrated excellent accuracy, sensitivity, and specificity. Clinical interpretations were more heterogeneous, probably owing to the low clinical penetrance of some common HFE genotypes.Genet Med 18 12, 1206-1213.


Assuntos
Testes Genéticos , Proteína da Hemocromatose/genética , Hemocromatose/diagnóstico , Hemocromatose/genética , Genótipo , Hemocromatose/patologia , Humanos , Mutação de Sentido Incorreto
14.
FASEB J ; 28(3): 1294-305, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24334703

RESUMO

The mechanisms by which maternal nutrient restriction (MNR) causes reduced fetal growth are poorly understood. We hypothesized that MNR inhibits placental mechanistic target of rapamycin (mTOR) and insulin/IGF-I signaling, down-regulates placental nutrient transporters, and decreases fetal amino acid levels. Pregnant baboons were fed control (ad libitum, n=11) or an MNR diet (70% of controls, n=11) from gestational day (GD) 30. Placenta and umbilical blood were collected at GD 165. Western blot was used to determine the phosphorylation of proteins in the mTOR, insulin/IGF-I, ERK1/2, and GSK-3 signaling pathways in placental homogenates and expression of glucose transporter 1 (GLUT-1), taurine transporter (TAUT), sodium-dependent neutral amino acid transporter (SNAT), and large neutral amino acid transporter (LAT) isoforms in syncytiotrophoblast microvillous membranes (MVMs). MNR reduced fetal weights by 13%, lowered fetal plasma concentrations of essential amino acids, and decreased the phosphorylation of placental S6K, S6 ribosomal protein, 4E-BP1, IRS-1, Akt, ERK-1/2, and GSK-3. MVM protein expression of GLUT-1, TAUT, SNAT-2 and LAT-1/2 was reduced in MNR. This is the first study in primates exploring placental responses to maternal undernutrition. Inhibition of placental mTOR and insulin/IGF-I signaling resulting in down-regulation of placental nutrient transporters may link maternal undernutrition to restricted fetal growth.


Assuntos
Regulação para Baixo , Fator de Crescimento Insulin-Like I/fisiologia , Insulina/fisiologia , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Animais , Feminino , Papio
15.
Paediatr Perinat Epidemiol ; 29(1): 60-71, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25492517

RESUMO

BACKGROUND: Nitrosatable drugs react with nitrite in the stomach to form N-nitroso compounds, observed in animal models to result in adverse pregnancy outcomes, such as birth defects and reduced fetal weight. Previous studies examining prenatal exposure to medications classified as nitrosatable have reported an increased risk of preterm births (PTBs) and small-for-gestational-age (SGA) infants. METHODS: Using data from mothers (controls) of babies without major birth defects from the National Birth Defects Prevention Study, prenatal nitrosatable drug usage by trimester and month of gestation was examined in relation to PTBs and SGA infants. RESULTS: Positive associations were observed with nitrosatable drug use and PTBs, with the strongest relationship with second trimester exposure (adjusted hazard ratio [aHR] 1.37, [95% confidence interval (CI) 1.10, 1.70]). Of the nitrosatable functional groups, secondary amines were the most notable, with a higher association among women with second (aHR 1.37, [95% CI 1.05, 1.79]) and third (aHR 1.34, [95% CI 1.02, 1.76]) trimester exposure compared with women with no prenatal nitrosatable drug use. Among SGA infants, a borderline association was noted with amide exposure during the third trimester (adjusted odds ratio 1.43 [95% confidence interval [CI] 1.00, 2.05]). CONCLUSIONS: Prenatal exposure to nitrosatable drugs during the second and third trimester of pregnancy, particularly secondary amines, might increase the risk of PTBs. However, prenatal exposure to nitrosatable drugs was not associated with SGA infants, with the exception of amide drugs.


Assuntos
Amidas/efeitos adversos , Aminas/efeitos adversos , Recém-Nascido Pequeno para a Idade Gestacional , Nascimento Prematuro/induzido quimicamente , Adolescente , Adulto , Amidas/administração & dosagem , Aminas/administração & dosagem , Ácido Ascórbico/administração & dosagem , Estudos de Casos e Controles , Suplementos Nutricionais , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Trimestres da Gravidez , Nascimento Prematuro/epidemiologia , Fatores de Risco , Estados Unidos/epidemiologia , Adulto Jovem
16.
Arch Toxicol ; 89(6): 967-77, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24888377

RESUMO

The genotoxicity of a complex mixture [neutral fraction (NF)] from a wood preserving waste and reconstituted mixture (RM) mimicking the NF with seven major polycyclic aromatic hydrocarbons (PAHs) and benzo(a)pyrene (BaP) was investigated by determining DNA adducts and tumor incidence in male B6C3F1 mice exposed to three different doses of the chemical mixtures. The peak values of DNA adducts were observed after 24 h, and the highest levels of PAH-DNA adducts were exhibited in mice administered NF + BaP, and the highest tumor incidence and mortality were also observed in this group. DNA adduct levels after 1, 7, or 21 days were significantly correlated with animal mortality and incidence of total tumors including liver, lung, and forestomach. However, only hepatic DNA adducts after 7 days significantly correlated with liver tumor incidence. Most proteins involved in DNA repair including ATM, pATR, Chk1, pChk1, DNA PKcs, XRCC1, FANCD2, Ku80, Mre11, and Brca2 were significantly lower in liver tumor tissue compared to non-tumor tissue. Expressions of proteins involved in apoptosis and cell cycle regulation were also significantly different in tumor versus non-tumor tissues, and it is possible that PAH-induced changes in these gene products are important for tumor development and growth.


Assuntos
Adutos de DNA/metabolismo , Reparo do DNA , Neoplasias Hepáticas Experimentais/induzido quimicamente , Fígado/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzo(a)pireno/química , Benzo(a)pireno/toxicidade , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos Endogâmicos , Estrutura Molecular , Hidrocarbonetos Policíclicos Aromáticos/química , Resíduos/efeitos adversos , Resíduos/análise
17.
Environ Chem Lett ; 13(4): 381-394, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28592954

RESUMO

Pharmaceuticals and personal care products (PPCP) are compounds with special physical and chemical properties that address the care of animal and human health. PPCP have been detected in surface water and wastewater in the ng/L to µg/L concentration range worldwide. PPCP ecotoxicity has been studied in a variety of organisms, and multiple methods have been used to assess the risk of PPCP in the environment to ecological health. Here we review the occurrence, effects, and risk assessment of PPCP in aquatic systems, as well as the sustainability of current methods for managing PPCP contamination in aquatic systems. The major points are the following: (1) a number of PPCP present potential concerns at environmentally relevant concentrations. PPCP mixtures may produce synergistic toxicity. (2) Various methods have been used for the ecological risk assessment of PPCP in aquatic systems. There are similarities in these methods, but no consensus has emerged regarding best practices for the ecological risk assessment of these compounds. (3) Human health risk assessments of PPCP contamination in aquatic systems have generally indicated little cause for concern. However, there is a lack of information regarding whether antibiotic contamination in wastewater and aquatic systems could lead to an increase in clinically relevant antibiotic-resistant bacteria and antibiotic-resistant genes. (4) Over the next century, the combination of increasing global population size and potential droughts may result in reduced water availability, increased need for water reuse, and increasing concentrations of PPCP in wastewaters. The current wastewater treatment methods do not remove all PPCP effectively. This, coupled with the possibility that antibiotics may promote the development of antibiotic-resistant bacteria and antibiotic-resistant genes, leads to concerns about the sustainability of global water supplies.

18.
Proc Natl Acad Sci U S A ; 108(7): 3011-6, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21252306

RESUMO

Moderate maternal nutrient restriction during pregnancy occurs in both developing and developed countries. In addition to poverty, maternal dieting, teenage pregnancy, and uterine vascular problems in older mothers are causes of decreased fetal nutrition. We evaluated the impact of global 30% maternal nutrient reduction (MNR) on early fetal baboon brain maturation. MNR induced major cerebral developmental disturbances without fetal growth restriction or marked maternal weight reduction. Mechanisms evaluated included neurotrophic factor suppression, cell proliferation and cell death imbalance, impaired glial maturation and neuronal process formation, down-regulation of gene ontological pathways and related gene products, and up-regulated transcription of cerebral catabolism. Contrary to the known benefits from this degree of dietary reduction on life span, MNR in pregnancy compromises structural fetal cerebral development, potentially having an impact on brain function throughout life.


Assuntos
Encéfalo/embriologia , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Papio/embriologia , Animais , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Morte Celular/fisiologia , Proliferação de Células , Feminino , Feto/embriologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/fisiologia , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Gravidez , Receptores de Somatomedina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
J Environ Sci Health B ; 49(3): 212-28, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24380621

RESUMO

Disinfection byproducts (DBPs) in drinking water exhibit considerable adverse health effects; recent focus is on the brominated disinfection byproducts (Br-DBPs). The chlorination and chloramination of bromide ion containing water produce reactive bromo species, which subsequently react with natural organic matter (NOM) to yield Br-DBPs. The possible reactions involved in generating DBPs are presented. Identified Br-DBPs include bromomethanes, bromoacetic acid, bromoacetamides, bromoacetonitriles, and bromophenols. Mixed chloro- and bromo-species have also been identified. Pathways of the formation of Br-DBPs have been described. The concentration of Br- ion, pH, reaction time, and the presence of Cu(II) influence the yield of DBPs. The effects of water conditions on the production of Br-DBPs are presented. The epidemiological studies to understand the potential toxic effects of DBPs including Br-DBPs are summarized. Brominated DBPs may have higher health risks than their corresponding chlorinated DBPs. A potential role of an emerging alternate disinfectant, ferrate (FeV)O(2-)4), in minimizing DBPs is briefly discussed.


Assuntos
Desinfetantes/química , Desinfetantes/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Purificação da Água/instrumentação , Halogenação , Humanos , Purificação da Água/métodos
20.
Plast Reconstr Surg Glob Open ; 12(3): e5665, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38440365

RESUMO

Background: Studies comparing carpal tunnel release with ultrasound guidance (CTR-US) to mini-open CTR (mOCTR) are limited. This randomized trial compared the efficacy and safety of these techniques. Methods: In this multicenter randomized trial, patients were randomized (2:1) to unilateral CTR-US or mOCTR. Outcomes included Boston Carpal Tunnel Questionnaire Symptom Severity Scale (BCTQ-SSS) and Functional Status Scale (BCTQ-FSS), numeric pain scale (0-10), EuroQoL-5 Dimension 5-Level (EQ-5D-5L), scar outcomes, and complications over 1 year. Results: Patients received CTR-US (n = 94) via wrist incision (mean 6 mm) or mOCTR (n = 28) via palmar incision (mean 22 mm). Comparing CTR-US with mOCTR, the mean changes in BCTQ-SSS (-1.8 versus -1.8; P = 0.96), BCTQ-FSS (-1.0 versus -1.0; P = 0.75), numeric pain scale (-3.9 versus -3.8; P = 0.74), and EQ-5D-5L (0.13 versus 0.12; P = 0.79) over 1 year were comparable between groups. Freedom from scar sensitivity or pain favored CTR-US (95% versus 74%; P = 0.005). Complications occurred in 2.1% versus 3.6% of patients (P = 0.55), all within 3 weeks postprocedure. There was one revision surgery in the CTR-US group, and no revisions for persistent or recurrent symptoms in either group. Conclusions: CTR-US and mOCTR demonstrated similar improvement in carpal tunnel syndrome symptoms and quality of life with comparable low complication rates over 1 year of follow-up. CTR-US was performed with a smaller incision and associated with less scar discomfort.

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