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1.
BMC Gastroenterol ; 24(1): 192, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840060

RESUMO

BACKGROUND: Gallstones are associated with obesity, and the BRI is a new obesity index that more accurately reflects body fat and visceral fat levels. The relationship between BRI and gallstone risk is currently unknown, and we aimed to explore the relationship between BRI and gallstone prevalence. METHODS: A cross-sectional study was conducted utilizing data from the 2017-2020 NHANES involving a total of 5297 participants. To assess the association between BRI and gallstones, we used logistic regression analysis, subgroup analysis, and interaction terms. In addition, we performed restricted cubic spline (RCS) analysis and threshold effects analysis to characterize nonlinear relationships. We assessed the ability of BRI and Body mass index (BMI) to identify gallstones using receiver operating curve (ROC) analysis and area under the curve (AUC), and compared them using the Delong test. RESULTS: Of the 5297 participants aged 20 years and older included in the study, 575 had gallstones. In fully adjusted models, a positive association between BRI and gallstone prevalence was observed (OR = 1.16, 95% CI: 1.12-1.20, P < 0.0001). Individuals in the highest quartile of BRI had a 204% increased risk of gallstones compared with those in the lowest quartile (OR = 3.04, 95% CI: 2.19-4.22, P < 0.0001). The correlation between BRI and gallstones persisted in subgroup analyses. RCS analyses showed a nonlinear relationship between BRI and gallstones. The inflection point was further found to be 3.96, and the correlation between BRI and gallstones was found both before and after the inflection point. ROC analysis showed that BRI (AUC = 0.667) was a stronger predictor of gallstones than BMI (AUC = 0.634). CONCLUSIONS: Elevated BRI is associated with an increased risk of gallstones in the U.S. population, and BRI is a stronger predictor of gallstones than BMI. Maintaining an appropriate BRI is recommended to reduce the incidence of gallstones.


Assuntos
Índice de Massa Corporal , Cálculos Biliares , Inquéritos Nutricionais , Obesidade , Humanos , Cálculos Biliares/epidemiologia , Feminino , Masculino , Estudos Transversais , Adulto , Pessoa de Meia-Idade , Prevalência , Obesidade/epidemiologia , Fatores de Risco , Adulto Jovem , Curva ROC , Idoso , Gordura Intra-Abdominal , Estados Unidos/epidemiologia
2.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791184

RESUMO

Recombinant adeno-associated virus (rAAV) has emerged as a prominent vector for in vivo gene therapy, owing to its distinct advantages. Accurate determination of the rAAV genome titer is crucial for ensuring the safe and effective administration of clinical doses. The evolution of the rAAV genome titer assay from quantitative PCR (qPCR) to digital PCR (dPCR) has enhanced accuracy and precision, yet practical challenges persist. This study systematically investigated the impact of various operational factors on genome titration in a single-factor manner, aiming to address potential sources of variability in the quantitative determination process. Our findings revealed that a pretreatment procedure without genome extraction exhibits superior precision compared with titration with genome extraction. Additionally, notable variations in titration results across different brands of dPCR instruments were documented, with relative standard deviation (RSD) reaching 23.47% for AAV5 and 11.57% for AAV8. Notably, optimal operations about DNase I digestion were identified; we thought treatment time exceeding 30 min was necessary, and there was no need for thermal inactivation after digestion. And we highlighted that thermal capsid disruption before serial dilution substantially affected AAV genome titers, causing a greater than ten-fold decrease. Conversely, this study found that additive components of dilution buffer are not significant contributors to titration variations. Furthermore, we found that repeated freeze-thaw cycles significantly compromised AAV genome titers. In conclusion, a comprehensive dPCR titration protocol, incorporating insights from these impact factors, was proposed and successfully tested across multiple serotypes of AAV. The results demonstrate acceptable variations, with the RSD consistently below 5.00% for all tested AAV samples. This study provides valuable insights to reduce variability and improve the reproducibility of AAV genome titration using dPCR.


Assuntos
Dependovirus , Vetores Genéticos , Genoma Viral , Dependovirus/genética , Vetores Genéticos/genética , Humanos , Reação em Cadeia da Polimerase/métodos , Células HEK293 , Terapia Genética/métodos , Carga Viral
3.
Food Sci Nutr ; 12(2): 765-775, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38370083

RESUMO

Formulas containing intact cow milk protein are appropriate alternatives when human milk (HM) is not feasible. However, for babies with a physician-diagnosed cow milk protein allergy (CMPA), hydrolyzed formulas are needed. We conducted a 3-month, open-label, nonrandomized concurrent controlled trial (ChiCTR2100046909) between June 2021 and October 2022 in Qingdao City, China. In this study, CMPA toddlers were fed with a partially hydrolyzed formula containing synbiotics (pHF, n = 43) and compared with healthy toddlers fed a regular intact protein formula (IF, n = 45) or HM (n = 21). The primary endpoint was weight gain; the secondary endpoints were changes in body length and head circumference of both CMPA and healthy toddlers after 3-month feeding; and the exploratory outcomes were changes in gut microbiota composition. After 3 months, there were no significant group differences for length-for-age, weight-for-age, or head circumference-for-age Z scores. In the gut microbiota, pHF feeding increased its richness and diversity, similar to those of IF-fed and HM-fed healthy toddlers. Compared with healthy toddlers, the toddlers with CMPA showed an increased abundance of phylum Bacteroidota, Firmicutes, class Clostridia, and Bacteroidia, and a decreased abundance of class Negativicutes, while pHF feeding partly eliminated these original differences. Moreover, pHF feeding increased the abundance of short-chain fatty acid producers. Our data suggested that this pHF partly simulated the beneficial effects of HM and shifted the gut microbiota of toddlers with CMPA toward that of healthy individuals. In conclusion, this synbiotic-containing pHF might be an appropriate alternative for toddlers with CMPA.

4.
Nutr Hosp ; 41(1): 96-111, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37522462

RESUMO

Introduction: Introduction: in previous studies, obesity was identified as a risk factor for inflammatory breast disease, but its causality is uncertain. In the present study, we performed a two-sample Mendelian randomization (TSMR) analysis to investigate the causal relationship between obesity and inflammatory breast disease. Methods: we use body mass index (BMI) as a measure of obesity. Data for single nucleotide polymorphisms (SNPs) associated with BMI were obtained from UK Biobank. Data for single nucleotide polymorphisms (SNPs) associated with mastitis were obtained from FinnGen Biobank. We used several MR analysis methods, such as inverse-variance weighting (IVW), MR-Egger, weighted median, simple mode and weighted mode to make our results more convincing. We also performed MR-PRESSO test, MR-Egger test, heterogeneity test, pleiotropy test and leave-one-out analysis to make our analysis results more robust and credible. We used odds ratio (OR) to evaluate the causal relationship between BMI and mastitis. Results: based on the IVW random effects model, we found that a one-standard deviation (SD) increase in BMI increased the risk of mastitis by 62.1 % (OR = 1.621, 95 % CI: 1.262-2.083, p = 1.59E-4), which is almost consistent with the results of several other methods. Conclusions: in European individuals, an increase in the number of BMI increases the risk of inflammatory breast disease. People with high BMI need to control their weight to reduce the incidence of inflammatory breast disease.


Introducción: Introducción: en estudios previos, la obesidad se identificó como un factor de riesgo para la enfermedad inflamatoria de mama, pero su causalidad es incierta. En el presente estudio, se realizó un análisis de aleatorización mendeliana de dos muestras (TSMR) para investigar la relación causal entre la obesidad y la enfermedad inflamatoria de mama. Métodos: se empleó el índice de masa corporal (IMC) como medida de obesidad. Los datos de los polimorfismos de nucleótido único (SNP) asociados con el IMC se obtuvieron del Biobank de Reino Unido y los datos de los polimorfismos de nucleótido único (SNP) asociados con la mastitis se obtuvieron de FinnGen Biobank. Se utilizaron varios métodos de análisis de RM, como la ponderación inversa de la varianza (IVW), RM-Egger, mediana ponderada, modo simple y modo ponderado para que nuestros resultados fueran más convincentes. También se realizaron la prueba MR-PRESSO, la prueba MR-Egger, la prueba de heterogeneidad, el test de pleiotropía y la validación dejando uno fuera (en inglés, leave-one-out) para que los resultados de nuestro análisis fueran más sólidos y creíbles. Se utilizó la odds ratio (OR) para evaluar la relación causal entre el IMC y la mastitis. Resultados: basándonos en el modelo de efectos aleatorios IVW, se halló que un aumento de una desviación estándar (DE) en el IMC aumentaba el riesgo de mastitis en un 62,1 % (OR = 1,621, IC 95 %: 1,262-2,083, p = 1,59E-4), que es casi consistente con los resultados de otros diversos métodos. Conclusiones: en los individuos europeos, un aumento del número de IMC aumenta el riesgo de enfermedad inflamatoria mamaria. Las personas con un IMC elevado deben controlar su peso para reducir la incidencia de enfermedad inflamatoria de la mama.


Assuntos
Mastite , Análise da Randomização Mendeliana , Feminino , Humanos , Índice de Massa Corporal , Obesidade/epidemiologia , Obesidade/genética , Razão de Chances , Estudo de Associação Genômica Ampla
5.
Water Res ; 249: 120993, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38086203

RESUMO

The co-occurrence of per- and polyfluoroalkyl substances (PFASs) and chlorinated aliphatic hydrocarbons (CAHs) in groundwater has drawn increased attention in recent years. No studies have been conducted concerning the oxidative degradation of PFASs and/or CAHs by in situ thermally activated persulfate (TAP) in groundwater, primarily due to the difficulty in cost-effectively achieving the desired temperature in the field. In this study, the effects and mechanisms of PFASs degradation by in situ TAP at a site with PFASs and CAHs co-contaminants were investigated. The target temperature of 40.0-70.0 °C was achieved in groundwater, and persulfate was effectively distributed in the demonstration area - the combination of which ensured the degradation of PFASs and CAHs co-contaminants by in situ TAP. It was demonstrated that the reductions of perfluoroalkyl carboxylic acids (PFCAs) concentration in all monitoring wells were in the range of 43.7 %-66.0 % by in situ TAP compared to those maximum rebound values in groundwater, whereas no effective perfluoroalkane sulfonic acids (PFSAs) degradation was observed. The conversion of perfluoroalkyl acids (PFAAs) precursors was one of the main factors leading to the increase in PFCAs concentrations in groundwater during in situ TAP. CAHs were effectively degraded in most monitoring wells, and furthermore, no inhibitory effects of CAHs and Cl- on the degradation of PFASs were observed due to the presence of sufficient persulfate. Additionally, there were significant increases in SO42- concentrations and reductions of pH values in groundwater due to in situ TAP, warranting their long-term monitoring in groundwater. The integrated field and laboratory investigations demonstrated that the reductions in PFCAs and CAHs concentrations can be achieved by the oxidative degradation of in situ TAP.


Assuntos
Fluorocarbonos , Água Subterrânea , Hidrocarbonetos Clorados , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Água Subterrânea/química , Hidrocarbonetos , Fluorocarbonos/análise
6.
J Hazard Mater ; 465: 133217, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38101019

RESUMO

In this study, the biodegradability of trifluoroacetate (TFA), perfluorooctanoic acid (PFOA), and perfluoro-2-methyl-3-oxahexanoic acid (HFPO-DA) by a native microbial community was evaluated over a 10-month incubation period. The observed microbial defluorination ratios and removal efficiency were 3.46 ( ± 2.73) % and 8.03 ( ± 3.03) %, 8.44 ( ± 1.88) % and 13.52 ( ± 4.96) %, 3.02 ( ± 0.62) % and 5.45 ( ± 2.99) % for TFA, PFOA and HFPO-DA, respectively. The biodegradation intermediate products, TFA and pentafluoropropionic acid (PFA), of PFOA and HFPO-DA were detected in their biodegradation treatment groups. Furthermore, the concentrations of the PFOA metabolites, perfluorohexanoic acid (PFHxA) and perfluoroheptanoic acid (PFHpA), in the aqueous solutions after incubation were quantified to be 0.21 and 4.14 µg/L. TFA, PFOA and HFPO-DA significantly reduced the microbial diversity and changed the structure of the community. The co-occurrence network analysis showed that low abundance species, such as Flexilinea flocculi, Bacteriovorax stolpii, and g_Sphingomonas, are positively correlated with the generation of fluoride ion, implying their potential collaborative functions contributing to the observed biodefluorination. The findings in this study can provide insights for the biodegradation of perfluoroalkyl carboxylic acids and their emerging alternatives by indigenous microorganisms in the environment.


Assuntos
Fluorocarbonos , Consórcios Microbianos , Propionatos , Ácido Trifluoracético , Fluorocarbonos/química , Caprilatos/química
7.
J Cancer Res Clin Oncol ; 150(1): 2, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38153521

RESUMO

PURPOSE: Among all primary breast tumors, malignant phyllodes tumor of the breast (MPTB) make up less than 1%. In the treatment of phyllode tumors, surgical procedures such as mastectomy and breast-conserving surgery are the mainstay. MPTB has, however, been controversial when it comes to treating it with RT. We aimed to explore the prognostic impact of RT and other clinicopathologic factors on long-term survival for patients with stage T3 or T4 malignant phyllodes tumors. METHODS: We select patients with stage T3 or T4 MPTB who qualified for the criteria between 2000 and 2018 via the Surveillance, Epidemiology, and End Results (SEER) database. We performed 1:1 propensity score matching (PSM) and Kaplan-Meier analysis to explore the role of RT in long-term survival of patients with stage T3 or T4 MPTB. A univariate and multivariate analysis of breast cancer-specific survival (BCSS) and overall survival (OS) risk factors was carried out using a Cox proportional hazards model. In addition, the nomogram graph of OS and BCSS was constructed. RESULTS: A total of 583 patients with stage T3 or T4 malignant phyllodes tumors were included in this study, of whom 154 (26.4%) received RT, and 429 (73.6%) were treated without RT. Before adjustment, between groups with and without RT, BCSS (p = 0.1) and OS (p = 0.212) indicated no significant difference respectively. Using of PSM, the two groups still did not differ significantly in BCSS (p = 0.552) and OS (p = 0.172). In multivariate analysis, age (p < 0.001), surgery of primary site (p < 0.001) and distant metastatic status (p < 0.001) were related to prognosis, while RT still did not affect BCSS (p = 0.877) and OS (p = 0.554). CONCLUSION: Based on the SEER database analysis, the study suggests that the patients with stage T3 or T4 MPTB treated with RT after surgery didn't have significant differences in BCSS or OS compared to those not treated with RT.


Assuntos
Neoplasias da Mama , Tumor Filoide , Humanos , Feminino , Neoplasias da Mama/radioterapia , Tumor Filoide/radioterapia , Tumor Filoide/cirurgia , Mastectomia , Mama , Bases de Dados Factuais
8.
Sci Total Environ ; 845: 157219, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35810894

RESUMO

Sequestration of soil carbon is considered as a promising strategy for mitigating climate change. As a source of recalcitrant carbon, biochar has been widely used in agricultural soil as a mean of stabilizing soil organic carbon (SOC). However, limited reports focused on the changes of biochar itself in soil when compared with the bulk SOC after biochar addition. To explore how environmental conditions influence the stability of biochar, isolated straw-derived biochar particles (0.25-2 mm) were embedded in an Anthrosol for 12 months under varied environmental conditions of incubation temperature (15 °C, 25 °C and 35 °C) and moisture (60 % and 150 % of saturated water content). Within the early 1 month of incubation, pH and inorganic nitrogen contents of biochar changed significantly as a function of moisture and temperature (p < 0.01), whereas water extractable organic carbon (WEOC) content was only influenced by moisture content (p < 0.01). The highest temperature (35 °C) and saturated water content (150 %) induced the largest aging response reflected by increases in oxygen-containing surface functional groups of biochar, including C-O-C (51.35 % - 149 %) and N-C-O (65.55 % - 119 %). Pearson correlation and RDA analysis indicated that the chemical properties of biochar contribute more to the carbon-source utilization properties of biochar colonized microbial community within 1 month of incubation, while the bulk soil chemical properties (pH, DOC, MBC and NO3-) had a higher contribution until the end of incubation. Moisture rather than temperature was the dominant factor in regulating the functional diversity of biochar colonized microbial community.


Assuntos
Carbono , Solo , Carbono/química , Carvão Vegetal/química , Solo/química , Temperatura , Água/química
9.
Sci Total Environ ; 805: 150260, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34537698

RESUMO

The performance of a permeable reactive barrier (PRB) for the in situ remediation of hexavalent chromium [Cr(VI)] contaminated groundwater, and the resulted responses in the indigenous microbial community, were investigated in a field-scale study. The PRB consisted of a mixture of zero-valent iron (ZVI), gravel and sand. The results showed that the PRB segment with 20% active reaction medium (ZVI) was able to successfully reduce Cr(VI) via chemical reduction from 27.29-242.65 mg/L to below the clean-up goal of 0.1 mg/L, and can be scaled-up under field conditions. It was found that the ZVI induced significant changes in the indigenous microbial community structure and compositions in the area of the PRB and those areas downgradient. The competitive growth among Cr(VI)-reducing bacteria (the reduced abundance of Hydrogenophaga, Pseudomonas, Exiguobacterium and Rhodobacter, along with the enrichment of Rivibacter and Candidatus_Desulforudis) were observed in PRB. In addition, Cr(VI)-reducing bacteria (Hydrogenophaga, Pseudomonas, Exiguobacterium and Rhodobacter) were enriched in the downgradient of PRB, indicating that Cr(VI) can be further bio-reduced to Cr(III). The Cr(VI) bio-reduction could serve as a secondary mechanism for further removal of Cr(VI) from contaminated groundwater, suggesting that the actual lifetime of a PRB can be prolonged, which is important for the design and economic assessment of a PRB. Further analysis revealed that pH, dissolved oxygen, Cr(VI) level, the oxidation-reduction potential, and temperature were the main environmental factors influencing the subsurface microbial community compositions.


Assuntos
Recuperação e Remediação Ambiental , Água Subterrânea , Microbiota , Poluentes Químicos da Água , Cromo/análise , Ferro , Poluentes Químicos da Água/análise
10.
Chemosphere ; 291(Pt 2): 132946, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34800501

RESUMO

There is an urgent need to investigate on the distribution and fate of short-chain analogues and emerging per- and polyfluoroalkyl substances (PFASs) in groundwater, and little research on their source apportionment and health risks through the drinking water exposure pathway has been carried out. In present study, the concentration and source of 22 PFASs, including five alternatives: 6:2 fluorotelomer sulfonate (6:2 FTS), potassium 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate (F-53B), hexafluoropropylene oxide trimer acid (HFPO-TA), hexafluoropropylene oxide dimer acid (HFPO-DA) and ammonium 4, 8-dioxa-3H-perfluorononanoate (ADONA), were analyzed in 88 groundwater samples from wells in Jiangxi Province, southeastern China. The total PFASs concentration (Σ18PFASs) in groundwater varied from 1.27 to 381.00 ng/L (mean 47.60 ng/L). Short-chain perfluorobutanoic acid (PFBA) and perfluoropentanoic acid (PFPeA) were the most abundant perfluorinated carboxylic acids (PFCAs), and short-chain perfluorobutanesulfonate (PFBS) was the most abundant perfluorinated sulfonic acids (PFSAs) in groundwater samples. The quantitative source apportionment by nonnegative matrix/tensor factorization coupled with k-means clustering (NMFk) model suggested that short-chain homologues and emerging alternatives have been used as substitutes for legacy PFOS and PFOA. Furthermore, the human risk assessment results showed that the estimated daily intakes (EDIs) for short-chain PFCAs were higher than that of PFOA, whereas the EDIs of PFBS, 6:2 FTS and F-53B were comparable to that of PFOS.


Assuntos
Ácidos Alcanossulfônicos , Água Potável , Fluorocarbonos , Água Subterrânea , Poluentes Químicos da Água , Alcanossulfonatos , Ácidos Alcanossulfônicos/análise , China , Monitoramento Ambiental , Fluorocarbonos/análise , Humanos , Medição de Risco , Poluentes Químicos da Água/análise
11.
Sheng Wu Gong Cheng Xue Bao ; 37(10): 3549-3564, 2021 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-34708610

RESUMO

Bioremediation is regarded as one of the most promising methods for the remediation of the soil and groundwater contaminated with organic compounds, mainly due to its cost-effectiveness and environmental friendliness. Using VOSviewer and CiteSpace, we analyzed all publications in this area in core database of Web of Science from 1990 to 2020. The number of publications in this area showed an increasing trend worldwide. The country with the largest total number of publications was USA, followed by China and India. Since 2012, the number of annual publications of China exceeded USA and ranked the first. The top three journals which published papers in this area were Chemosphere, Environmental Science & Technology, and Science of the Total Environment. The Chinese Academy of Sciences published the largest number of papers among the research institutions globally, but the University of California in USA had the highest total citations and h-index. Bibliometric analysis indicated that it is important to develop biotechnologies of bioremediation coupled with chemical/physical remediation to overcome the challenge of low efficiency and long remediation duration associated with bioremediation. In addition, the bioremediation on the mixed contaminants, such as organic contaminants and heavy metals, or mixtures of different organic contaminants, is an important direction. Finally, the rapid development of microbiome technologies will further promote the exploration of mechanisms involved in bioremediation on the genetic and molecular level.


Assuntos
Bibliometria , Água Subterrânea , Biodegradação Ambiental , Publicações , Solo
12.
Sci Total Environ ; 772: 145495, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33770851

RESUMO

A large gap exists between laboratory findings and successful implementation of bioremediation technologies for the treatment of chromium (Cr)-contaminated sites. This work conducted the enhanced bioremediation of Cr(VI) in situ via the addition of organic carbon (ethanol) coupled with a dynamic groundwater recirculation (DGR)-based system in a field-scale study. The DGR system was applied to successfully (1) remove Cr(VI) from groundwater via enhanced flushing by the recirculation system and (2) deliver the biostimulant to the heterogeneous subsurface environment, including a sand/cobble aquifer and a fractured bedrock aquifer. The results showed that the combined extraction and bioreduction of Cr(VI) were able to reduce Cr(VI) concentrations from 1000 to 2000 mg/L to below the clean-up goal of 0.1 mg/L within the operation period of 52 days. The effectiveness of Cr(VI) bioremediation and the relationship between microbial communities and geochemical parameters were evaluated. Multiple-line of evidence demonstrated that the introduction of ethanol significantly stimulated a variety of bacteria, including those responsible for denitrification, sulfate reduction and reduction of Cr(VI), which contributed to the establishment of reducing conditions in both aquifers. Cr(VI) was removed from groundwater via combined mechanisms of physical removal through the DGR system and the bioreduction of Cr(VI) followed by precipitation. In particular, it was found competitive growth among Cr(VI)-reducing bacteria (such as the enrichment of Geobacter, along with the reduced relative abundance of Acinetobacter and Pseudomonas) was induced by ethanol injection. Furthermore, Cr(VI), total organic carbon, NO2-, and SO42- played important roles in shaping the composition of the microbial community and its functions.


Assuntos
Água Subterrânea , Biodegradação Ambiental , Cromo/análise , Oxirredução
13.
Chemosphere ; 252: 126443, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32182509

RESUMO

Chlorinated polyfluoroalkyl ether sulfonates (trade name F-53B) has been detected in various environmental matrices, and reported to be equally or more toxic than perfluorooctane sulfonate. Efficient sorptive removal of F-53B from water by two types of layered double hydroxides (LDHs), NO3--LDH and sodium dodecyl sulfate modified NO3--LDH (SDS-LDH), was demonstrated in this study. Both LDHs removed F-53B in several minutes and had sorption capacities of over 860 mg/g. SDS-LDH exhibited a greater F-53B uptake than NO3--LDH under the influence of different solution chemistry, including pH 3-11, or in the presence of competing anions or co-contaminants, primarily due to the higher surface areas and the presence of SDS for SDS-LDH. Batch experiments, structural characterization, molecular dynamics simulations, and density functional theory calculations were combined to explore the sorption mechanisms, which mainly include ion exchange (specifically, O-H⋯O/F hydrogen bond), C-F/Cl⋯H hydrogen bond, and micellar sorption (occurring at high initial F-53B concentrations). Accordingly, we propose to improve the sorption performance of LDHs by increasing their surface areas and modifying LDHs to produce more hydrogen bond sites, as well as exfoliating LDHs into two dimensional nanosheets to eliminate the steric hindrance for the micellar formation of F-53B or other per- and polyfluoroalkyl substances.


Assuntos
Alcanossulfonatos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Alcanossulfonatos/análise , Ácidos Alcanossulfônicos , Fluorocarbonos , Hidróxidos/química , Troca Iônica , Dodecilsulfato de Sódio , Soluções , Água , Poluentes Químicos da Água/análise
14.
Environ Pollut ; 253: 449-463, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325890

RESUMO

Sustainable remediation is a goal in the remediation industry. Thermal treatment can remediate contaminated sites quickly and reliably, but its energy-intensive nature and potential to damage soil properties make it seemingly not sustainable. This review evaluates the potential for thermal treatment to become a sustainable remediation technology based on a comprehensive analysis of the scientific literature. The fundamentals, advantages, and limitations of single thermal treatment technologies are summarized. The compatibility and advantages of thermal treatment coupled with thermal, physicochemical, or biological technologies are reviewed. The results suggest that ingeniously designed coupled technologies can improve the availability and removal efficiency of contaminant, suppress the production of toxic byproduct, and reduce the required heating temperature and energy input. The sustainability of thermal treatment is then discussed from the perspectives of energy efficiency and land reuse. Approaches for improving energy efficiency include applying solar energy-based technologies, smoldering-based technologies, and coupled technologies. For land reuse, heating below 250 °C has negligible adverse impacts on most soil properties, and can increase nutrient availability and release dissolved organic carbon to support the growth of microorganisms and plants. Heating above 250 °C can significantly reduce soil organic matter and clay content, which decreases the soil cation exchange capacity and water holding capacity, and consequently damages the soil fertility. Some restoration strategies are also proposed for the recovery of soil quality. In addition, thermally remediated soil is considered to be a good candidate as an engineering medium for construction. This review concludes with an outlook of future research efforts that will further shift thermal treatment toward sustainable remediation.


Assuntos
Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/química , Poluição Ambiental/análise , Temperatura Alta , Solo/química , Poluentes do Solo/análise , Temperatura
15.
Chemosphere ; 216: 507-515, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30388686

RESUMO

6:2 chlorinated polyfluorinated ether sulfonate (trade name F-53B), a perfluorooctane sulfonate alternative used as a mist suppressant in the chromium plating industry, is environmentally persistent and bioaccumulative. In this study, the kinetic and equilibrium data of F-53B sorption onto soils were obtained to investigate the relationship between sorption parameters and soil attributes. The effects of potential coexisting Cu(II), anionic Cr(VI) and sulfate on F-53B sorption by soils were explored. This is the first report of the effects of F-53B sorption behavior on soils with coexisting contaminants of Cu(II) and Cr(VI). The results showed that sorption kinetics of F-53B on soils could be well-fitted by the pseudo-second-order model. The maximum F-53B sorption capacity ranged from 22.71 to 92.36 mg/kg on six different soils, and the correlation analysis indicated a positive relationship between the maximum sorption capacity and the soil organic content, Al2O3, and Fe2O3. The desorption percentages of F-53B in this study, defined as the proportion of sorbed F-53B on soils that was recovered upon desorption, were lower than 8.2%. Moreover, F-53B sorption capacities generally decreased in the presence of Cu(II), Cr(VI), and sulfate, indicating that these ions can facilitate the F-53B mobility in the subsurface. Taken together, these findings suggest that electrostatic interaction, hydrophobic interaction, ligand exchange, and surface complexation contributed to the F-53B sorption on soils.


Assuntos
Cromo/química , Poluentes do Solo/química , Solo/química , Sulfatos/química , Adsorção
16.
Ecotoxicol Environ Saf ; 152: 141-150, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29402442

RESUMO

Little research has been carried out for the per- and polyfluoroalkyl substances (PFASs) in groundwater from non-industrial areas, even though it has been proved that PFASs can transport for long distance. In this study, the concentration profiles and geographical distribution of 14 PFASs, including two alternatives of perfluorooctane sulfonate (PFOS), 6:2 fluorotelomer sulfonate (6:2 FTS) and potassium 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate (F-53B), were analyzed in groundwater samples (n = 102) collected from water wells in non-industrial areas. The total concentrations of PFASs (Σ14PFASs) in groundwater samples ranged from 2.69 to 556 ng/L (mean 43.1 ng/L). The detection rates of shorter chain (C4-C9) PFASs were 62.75-100%, higher than those of long chain (> C10) PFASs with detection rates of less than 40%. The source identification using hierarchical cluster analysis and Spearman rank correlation analysis suggested that domestic sewage and atmospheric deposition may contribute significantly to the PFAS occurrence in groundwater in non-industrial areas, while the nearby industrial parks may contribute some, but not at a significant level. Furthermore, the human health risk assessment analysis shows that the health hazards associated with perfluorooctanoic acid (PFOA) and PFOS, two of the main PFAS constituents in groundwater from non-industrial areas, were one or two orders of magnitude higher than those in a previous study, but were unlikely to cause long-term harm to the residents via the drinking water exposure pathway alone.


Assuntos
Ácidos Alcanossulfônicos/análise , Caprilatos/análise , Monitoramento Ambiental/métodos , Fluorocarbonos/análise , Água Subterrânea/química , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/química , Caprilatos/química , China , Água Potável/análise , Fluorocarbonos/química , Humanos , Medição de Risco , Estações do Ano , Esgotos , Poluentes Químicos da Água/química
17.
Chemosphere ; 187: 196-205, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28846976

RESUMO

Perfluorooctane sulfonate (PFOS) is known to be extremely persistent and is toxic to wildlife and humans. In this study, we evaluated the sorptive removal behavior of PFOS from aqueous solution using three forms of layered double hydroxides (LDHs), namely, nitrate-, carbonate- and chloride-intercalated LDHs. Batch experiments showed that the sorption process was very fast with an equilibrium time of 10-60 min. The nitrate-LDH had the greatest ability to remove PFOS with a removal rate of 99.7% at an initial concentration of 100 mg/L and the maximum uptake capacity reached 865 mg/g. The sorption kinetic and equilibrium data could be fitted well with the pseudo-second-order model and Langmuir model, respectively. The intraparticle diffusion model suggests that both external diffusion and intraparticle diffusion are the rate-limiting processes for PFOS sorption onto the LDHs. The initial pH, background electrolyte concentration and coexisting ions influenced the sorption of PFOS by the LDHs. It was concluded that both surface adsorption and anion exchange were involved in the PFOS sorption onto the LDHs.


Assuntos
Ácidos Alcanossulfônicos/isolamento & purificação , Fluorocarbonos/isolamento & purificação , Hidróxidos/farmacologia , Purificação da Água/métodos , Adsorção , Cloretos , Difusão , Cinética , Nitratos , Água
18.
Ecotoxicol Environ Saf ; 142: 40-50, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28384502

RESUMO

Perfluorooctane sulfonate (PFOS), an emerging contaminant, is environmentally persistent, bioaccumulative and toxic to human health and ecosystems. It has been widely detected in groundwater, surface water, soil and sediment. So far, very few research has reported on the PFOS sorption behaviors onto soils, one of the primary processes that influence its fate and transport in the subsurface. In this study, the sorption and desorption of PFOS onto six soils with different physicochemical properties were investigated. Kinetic and equilibrium studies of PFOS sorption onto six soils were carried out in batch experiment. The sorption kinetics of PFOS on the six soils demonstrated that PFOS sorption reached equilibrium within 48h, and the well-fitted pseudo-second-order kinetic model to experimental data suggested that chemisorption was involved in PFOS sorption on soils. The intraparticle diffusion model results indicated that both film diffusion and intraparticle diffusion were the rate-limiting steps for five of the six soil samples, while the intraparticle diffusion was the only limiting step in the PFOS sorption on the sixth soil. PFOS sorption isotherms can be described by the Freundlich model well for all six soils (R2=0.979-0.999). The correlation analysis between KF of PFOS and the physicochemical properties of the soils showed that a positive correlation between KF and Al2O3, SOC and Fe2O3. The FTIR data demonstrated hydrophobic interaction, ion exchange, surface complexing and hydrogen bonding might all play a role in the PFOS sorption onto soil samples. PFOS sorption onto soil minerals, especially iron oxide minerals, needs to be further explored in future.


Assuntos
Ácidos Alcanossulfônicos/análise , Fluorocarbonos/análise , Modelos Teóricos , Poluentes do Solo/análise , Solo/química , Adsorção , China , Humanos , Cinética
19.
Huan Jing Ke Xue ; 35(4): 1462-7, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-24946603

RESUMO

As an excellent biological resource, Chlorella has wide applications for production of biofuel, bioactive substances and water environment restoration. Therefore, it is very important to understand the photosynthetic physiology characteristics of Chlorella. Magnesium ions play an important role in the growth of microalgae, not only the central atom of chlorophyll, but also the cofactor of some key enzyme in the metabolic pathway. A laboratory study was conducted to evaluate the effects of magnesium deficiency on several photosynthetic and physiological parameters and the triacylglyceride (TAG) accumulation of the green alga, Chlorella vulgaris, in the photoautotrophic culture process. Chlorella vulgaris biomass, protein, chlorophyll a and chlorophyll b contents decreased by 20%, 43.96%, 27.52% and 28.07% in response to magnesium deficiency, while the total oil content increased by 19.60%. Moreover, magnesium deficiency decreased the maximal photochemical efficiency F(v)/F(m) by 22.54%, but increased the non-photochemical quenching parameters qN. Our results indicated the decline of chlorophyll caused by magnesium, which affected the photosynthesis efficiency, lead to the growth inhibition of Chlorella vulgaris and affected the protein synthesis and increased the triacylglyceride (TAG) accumulation.


Assuntos
Chlorella vulgaris/metabolismo , Chlorella vulgaris/fisiologia , Magnésio/metabolismo , Fotossíntese , Triglicerídeos/metabolismo , Biomassa , Clorofila/análise , Clorofila A
20.
Phytother Res ; 26(10): 1449-65, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22389143

RESUMO

Many anticancer drugs are obtained from natural sources. Nature produces a variety of toxic compounds, which are often used as anticancer drugs. Up to now, there are at least 120 species of poisonous botanicals, animals and minerals, of which more than half have been found to possess significant anticancer properties. In spite of their clinical toxicity, they exhibit pharmacological effects and have been used as important traditional Chinese medicines for the different stages of cancer. The article reviews many structures such as alkaloids of Camptotheca acuminata, Catharanthus roseus and Cephalotaxus fortunei, lignans of Dysosma versipellis and Podophyllum emodi, ketones of Garcinia hanburyi, terpenoids of Mylabris and Ginkgo biloba, diterpenoids of Tripterygium wilfordii, Euphorbia fischeriana, Euphorbia lathyris, Euphorbia kansui, Daphne genkwa, Pseudolarix kaempferi and Brucea javanica, triterpenoids of Melia toosendan, steroids of Periploca sepium, Paris polyphylla and Venenum Bufonis, and arsenic compounds including Arsenicum and Realgar. By comparing their related phytochemistry, toxic effects and the recent advances in understanding the mechanisms of action, this review puts forward some ideals and examples about how to increase antitumour activity and/or reduce the side effects experienced with Chinese medicine.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/toxicidade , Neoplasias/tratamento farmacológico , Alcaloides/farmacologia , Animais , Humanos , Cetonas/farmacologia , Lignanas/farmacologia , Medicina Tradicional Chinesa , Fitoterapia , Plantas Medicinais/química , Esteroides/farmacologia , Terpenos/farmacologia
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