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1.
Environ Sci Technol ; 57(26): 9702-9712, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37314230

RESUMO

Hexafluoropropylene oxide (HFPO) homologues, which are important alternatives to perfluorooctanoic acid, have been frequently identified in crops. Although exposure to HFPO homologues via crops may pose non-negligible threats to humans, their impact on crops is still unknown. In this study, the accumulation, transport, and distribution mechanisms of three HFPO homologues in lettuce were investigated at the plant, tissue, and cell levels. More specifically, HFPO trimer acid and HFPO tetramer acid were primarily fixed in roots and hardly transported to shoots (TF, 0.06-0.63). Conversely, HFPO dimer acid (HFPO-DA) tended to accumulate in lettuce shoots 2-264 times more than the other two homologues, thus resulting in higher estimated daily intake values. Furthermore, the dissolved organic matter derived from root exudate enhanced HFPO-DA uptake by increasing its desorption fractions in the rhizosphere. The transmembrane uptake of HFPO homologues was controlled by means of a transporter-mediated active process involving anion channels, with the uptake of HFPO-DA being additionally facilitated by aquaporins. The higher accumulation of HFPO-DA in shoots was attributed to the larger proportions of HFPO-DA in the soluble fraction (55-74%) and its higher abundance in both vascular tissues and xylem sap. Our findings expand the understanding of the fate of HFPO homologues in soil-crop systems and reveal the underlying mechanisms of the potential exposure risk to HFPO-DA.


Assuntos
Fluorocarbonos , Lactuca , Humanos , Fluorocarbonos/análise , Lactuca/química , Óxidos
2.
Environ Sci Technol ; 54(13): 8210-8220, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32388996

RESUMO

Neonicotinoids (NEOs) are insecticides that are widely used around the world. Following exposure, NEOs get metabolized in human bodies. The biomarkers to assess human NEO exposure are not well described because of the lack of information on the metabolites of NEOs (m-NEOs). In this study, five m-NEOs including N-desmethyl-acetamiprid (N-dm-ACE), 5-hydroxy-imidacloprid (5-OH-IMI), olefin-imidacloprid (Of-IMI), 1-methyl-3-(tetrahydro-3-furylmethyl) guanidine (DIN-G), and 1-methyl-3-(tetrahydro-3-furylmethyl) (DIN-U) were measured in 275 urine samples collected from 10 cities in China. All of the m-NEOs were frequently detected in urine samples with the median concentrations ranging from 0.42 (DIN-G) to 1.02 (5-OH-IMI) ng/mL. The urinary concentrations of N-dm-ACE and 5-OH-IMI measured in China were higher than those reported from Japan and the USA. In comparison to the parent NEO (i.e., acetamiprid, ACE; imidacloprid, IMI; and dinotefuran, DIN) concentrations reported in the same set of samples by our research group, the median ratios of m-NEO to the corresponding parent NEO (m-NEO/NEO) ranged from 4.95 (DIN-G/DIN) to 37.7 (N-dm-ACE/ACE), indicating that NEOs are mainly present as metabolites rather than the parent forms. Furthermore, the ratio of Σm-NEOs/ΣNEOs was significantly (p < 0.01) higher in females than in males, suggesting that NEOs are more readily metabolized in females or females are more highly exposed to m-NEOs. To our knowledge, this is the first study to measure Of-IMI, DIN-G, and DIN-U levels in urine samples from China. We recommend biomonitoring studies to include N-dm-ACE, 5-OH-IMI, and DIN-U (and DIN-G) for clear understanding of human exposure to ACE, IMI, and DIN, respectively.


Assuntos
Inseticidas , Monitoramento Biológico , China , Feminino , Humanos , Inseticidas/análise , Japão , Masculino , Neonicotinoides , Nitrocompostos
3.
Ecotoxicol Environ Saf ; 191: 110235, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31986458

RESUMO

Six parabens and their four metabolites were measured in paired maternal serum (MS) and cord serum (CS) samples collected from 95 pregnant women to elucidate placental transfer of this class of compounds. Matched maternal urine (MU) and amniotic fluid (AF) collected from 13 of 95 pregnant women were also analyzed to examine partition of these chemicals between maternal and fetal tissues. The placental transfer rates (PTRs; concentration ratio of parabens between CS and MS) of methyl- (MeP), ethyl- (EtP), propyl-parabens (PrP) were 0.81, 0.63, and 0.60, respectively. Furthermore, the PTRs of OH-MeP (0.93) and OH-EtP (1.8) were higher than those of their corresponding parent parabens, which suggested that hydroxylation increased placental transfer rates of parabens. Structure-dependent placental transfer mechanisms were observed. A significant negative correlation between molecular weights (or log Kow) of MeP, EtP, PrP, and p-hydroxy benzoic acid (4-HB) and PTRs suggested passive diffusion as a mechanism of placental transfer of these chemicals. Nevertheless, other hydroxylated metabolites (OH-EtP, OH-MeP, and 3,4-dihydroxy benzoic acid (3,4-DHB)) showed a positive correlation between molecular weight (or log Kow) and PTRs, which suggested that the placental transfer is mediated by protein binding of these metabolites. The MU to MS concentration ratios of MeP (MU/MSMeP) and PrP (MU/MSPrP) were 71 and 81, respectively, and MU/MSMeP was two orders of magnitude higher than that found for the metabolite (MU/MSOH-MeP: 0.35), suggesting that hydroxylation metabolite reduced urinary elimination of parabens. To our knowledge, this is the first time to report the occurrence and distribution of parabens and their metabolites in paired maternal-fetal serum, urine, and AF samples in China. Our results provide novel information on placental transfer of parabens and their metabolites.


Assuntos
Líquido Amniótico/química , Sangue Fetal/química , Exposição Materna , Troca Materno-Fetal , Parabenos/análise , Placenta/química , Líquido Amniótico/metabolismo , China , Cosméticos , Feminino , Sangue Fetal/metabolismo , Humanos , Parabenos/metabolismo , Placenta/metabolismo , Gravidez
4.
Ecotoxicol Environ Saf ; 169: 822-828, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597781

RESUMO

In the present study, concentrations of bisphenol A (BPA) and its six alternatives were quantified in serum samples collected from elder population living around an e-waste recycling facilities as well as an reference area in China. BPA, bisphenol AF (BPAF), and bisphenol F (BPF) were frequently detected (detection rates: > 65%) in serum samples collected from residents living near e-waste dismantling facilities, with geometric mean (GM) concentrations of 3.2, 0.0074, and 0.062 ng/mL, respectively. The detection frequencies of other four bisphenols (BPs) in serum samples were lower than 25%, regardless of the sampling areas. Significant difference (Mann-Whitney U-test, p < 0.05) was observed in the serum concentration of BPA, but not BPAF and BPF, between the e-waste recycling and reference areas. This finding indicated e-waste dismantling activities are correlated with human BPA exposure. Significant higher (p < 0.05) detection rates of donors who had abnormal fasting blood glucose (FBG) levels were found in e-waste recycling areas (45%) than those found in reference area. Our results suggested BPA and BPAF exposure might associated with abnormal FBG in participants living in e-waste sites. To our knowledge, this study is first determination of BPs in serum samples and assessment of health risk of elderly people from BPs exposure in e-waste dismantling area.


Assuntos
Compostos Benzidrílicos/sangue , Glicemia/análise , Exposição Ambiental/análise , Poluentes Ambientais/sangue , Fenóis/sangue , Idoso , China , Resíduo Eletrônico , Jejum , Feminino , Humanos , Reciclagem
5.
Biochem Biophys Res Commun ; 474(2): 351-356, 2016 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-27109477

RESUMO

The nuclear receptor Farnesoid X Receptor (FXR) is likely a tumor suppressor in liver tissue but its molecular mechanism of suppression is not well understood. In this study, the gene expression profile of human liver cancer cells was investigated by microarray. Bioinformatics analysis of these data revealed that FXR might regulate the mTOR/S6K signaling pathway. This was confirmed by altering the expression level of FXR in liver cancer cells. Overexpression of FXR prevented the growth of cells and induced cell cycle arrest, which was enhanced by the mTOR/S6K inhibitor rapamycin. FXR upregulation also intensified the inhibition of cell growth by rapamycin. Downregulation of FXR produced the opposite effect. Finally, we found that ectopic expression of FXR in SK-Hep-1 xenografts inhibits tumor growth and reduces expression of the phosphorylated protein S6K. Taken together, our data provide the first evidence that FXR suppresses proliferation of human liver cancer cells via the inhibition of the mTOR/S6K signaling pathway. FXR expression can be used as a biomarker of personalized mTOR inhibitor treatment assessment for liver cancer patients.


Assuntos
Proliferação de Células , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transdução de Sinais
8.
Acta Pharmacol Sin ; 36(1): 37-43, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25500874

RESUMO

Farnesoid X receptor (FXR) is a member of the nuclear receptor family and a ligand-modulated transcription factor. In the liver, FXR has been considered a multi-functional cell protector and a tumor suppressor. FXR can suppress liver carcinogenesis via different mechanisms: 1) FXR maintains the normal liver metabolism of bile acids, glucose and lipids; 2) FXR promotes liver regeneration and repair after injury; 3) FXR protects liver cells from death and enhances cell survival; 4) FXR suppresses hepatic inflammation, thereby preventing inflammatory damage; and 5) FXR can directly increase the expression of some tumor-suppressor genes and repress the transcription of several oncogenes. However, inflammation and epigenetic silencing are known to decrease FXR expression during tumorigenesis. The reactivation of FXR function in the liver may be a potential therapeutic approach for patients with liver cancer.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia
9.
Sci Total Environ ; 913: 169674, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38160827

RESUMO

Pomelo (Citrus grandis) is a highly popular and juicy member of the citrus family. However, little is known regarding the occurrence and distribution of pesticides in pomelo. In this study, we determined the levels of legacy (n = 25) and current-use pesticides (n = 2) in all parts of pomelo (i.e., epicarp, mesocarp, endocarp, pulp, and seed) and paired soil and leaf samples collected from two pomelo orchards in South China. At least one target pesticide was detected in the pomelo fruit, soil, and leaf samples, indicating that these pesticides were ubiquitous. The spatial distribution of the total concentration of pesticides in the pomelo parts was in the order of epicarp (216 ng/g) > mesocarp (9.50 ng/g) > endocarp (4.40 ng/g) > seed (3.80 ng/g) > pulp (1.10 ng/g), revealing different spatial distributions in pomelo. Principal component analysis was performed based on the concentrations of the target pesticides in the pulp and paired samples of epicarp, leaf, topsoil, and deep soil to examine the translocation pathway of the pesticides in pomelo. Close correlations were found among the target pesticides, and the pesticides in the pulp were mainly transferred from the epicarp, topsoil, or deep soil. We also explored the factors that affected such transport and found that the main translocation pathway of the non-systemic pesticide (i.e., buprofezin) into the pulp was the epicarp, whereas the systemic pesticide (i.e., pyriproxyfen) was mainly derived from the soil. The cumulative chronic dietary risks of all the pesticides resulting from pomelo consumption were much lower than the acceptable daily intake values for the general population. However, the prolonged risk of exposure to these pesticides should not be underestimated. The potential health risks posed by legacy and current-use pesticides, which are widely and frequently utilized, should be given increased attention.


Assuntos
Citrus , Resíduos de Praguicidas , Praguicidas , Humanos , Praguicidas/análise , Frutas/química , Solo , China , Sementes/química , Resíduos de Praguicidas/análise
10.
J Surg Case Rep ; 2023(12): rjad689, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38163058

RESUMO

Spinal gout is a rare occurrence, and the combination of gout with lumbar spondylolysis has not been reported. We present a unique case involving a 29-year-old male who complained of low back pain for 1 month. Computed tomography and magnetic resonance imaging revealed articular subchondral erosions and a mass in the left L5-S1 facet joints. Initially treated for a spinal infection, the patient subsequently underwent lumbar spinal canal decompression and fusion, achieving complete relief. Postoperative pathology confirmed the spinal lesions to be tophaceous gout. Dual-energy CT or biopsy can assist in confirming the diagnosis. This report discusses another rare case of tophaceous gouty arthritis with spondylolysis to be added to the literature.

11.
Sci Total Environ ; 901: 165935, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-37532038

RESUMO

Neonicotinoid insecticides (NEOs) as well as their metabolites are highly mobile on the subsurface and can potentially contaminate drinking water sources; however, their pollution status and fate in the drinking water system remains ambiguous. In this study, six parent NEOs and two characteristic metabolites were measured in drinking water source protection area (source water, n = 52) and two related drinking water treatment plants (DWTPs) (n = 88) located in the Dongguan section of the Pearl River. The ubiquitous of NEOs was observed in source water with the mean concentration of total NEOs (ΣNEOs) at 240 ng/L. Although advanced DWTP (A-DWTP; range: 26 % to 100 %) showed better removals of ΣNEOs and all individual NEOs rather than those in conventional DWTP (C-DWTP; range: -53 % to 28 %), the removals were still low for acetamiprid (ACE, 26 %), thiacloprid (THD, 59 %), thiamethoxam (THM, 56 %) and N-desmethyl-acetamiprid (N-dm-ACE, 45 %) in A-DWTP. Removal rates were positive in chlorination (48 %), final stage of sedimentation (F-Sed, 24 %), and granular activated carbon (GAC) filter effluent (19 %) in A-DWTP. It worthy to note that ΣNEOs has high negative removal rates at the start stage of sedimentation (S-Sed, -83 %), middle stage of sedimentation (M-Sed, -47 %), and sand filter effluent (-42 %) water in C-DWTP, which resulted in negative removals of ΣNEOs (-9.6 %), imidacloprid (IMI, -22 %), clothianidin (CLO, -37 %), flupyradifurone (FLU, -76 %), and N-dm-ACE (-29 %) in C-DWTP. Residual levels of NEOs were high in source water, and their low or negative removals in DWTPs should be highly concerning. Results would fill the existing knowledge gap of NEOs in aquatic environment and provide a scientific dataset for policy-making on pollution control and environmental protection.

12.
Sci Total Environ ; 857(Pt 2): 159295, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36228796

RESUMO

As a kind of emerging pollutant, volatile organic compounds (VOCs) are getting increasing attention due to their contribution to the formation of atmospheric haze and O3. Photocatalytic oxidation under vacuum ultraviolet photocatalytic oxidation (VUV-PCO) presents a promising method for VOCs degradation, but it is seldom studied for VOCs compound and the mechanism is still elusive. Herein, typical VOCs such as toluene and ethyl acetate were degraded separately or together in VUV system and in VUV-PCO system with the designed trifunctional catalyst Mn/TiO2/ZSM-5. Intermediates were recognized by PTR-TOF-MS. It is found that dual VOCs mixture outperformed single VOCs under both VUV process and VUV-PCO process. Possible degradation mechanisms were proposed. To explore the potential practicality of VUV-PCO technology, scale-up synthesis of Mn/TiO2/ZSM-5 on ceramic foams was successfully carried out and assembled into a homemade pilot-scale VUV-PCO equipment for the control of simulated VOCs complex (toluene, ethyl acetate, ethanol, and acetone). Pilot-scale catalytic testing with the monolithic catalysts achieved high removal efficiency (over 90 % efficiency after two cycles of regeneration) and confirmed the practical application possibility of VUV-PCO technology in multiple VOCs degradation. This work probes into the VUV-PCO technology applicability from lab scale to pilot scale and promotes the understanding of VUV and VUV-PCO in VOCs complex decomposition.


Assuntos
Compostos Orgânicos Voláteis , Vácuo , Raios Ultravioleta , Catálise , Oxirredução , Tolueno
13.
Am J Physiol Gastrointest Liver Physiol ; 303(11): G1245-53, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23042943

RESUMO

The nuclear receptor farnesoid X receptor (FXR) acts as a liver protector by regulating normal liver homeostasis. Spontaneously developed liver tumors have been found in FXR-null mice. However, the role of FXR in the tumorigenesis of human hepatocellular carcinoma (HCC) is still poorly understood. In this study, we measured the expression of FXR and its primary target gene, small heterodimer partner, and analyzed the clinical significance of FXR expression in HCC patients. A lentiviral vector that selectively overexpresses FXR was used to investigate the function of FXR in HCC cell proliferation both in vitro and in vivo. Our data showed that in human HCC, FXR expression was significantly reduced and was positively correlated with multiple malignant clinicopathological characteristics. Lentivirus-mediated exogenous FXR expression resulted in a marked increase of small heterodimer partner expression, significant repression of liver cancer cell proliferation, and tumor growth in nude mice. These results suggest that FXR may be of clinical and pharmacological importance as a promising biomarker of HCC.


Assuntos
Carcinoma Hepatocelular/fisiopatologia , Neoplasias Hepáticas/fisiopatologia , Receptores Citoplasmáticos e Nucleares/biossíntese , Animais , Carcinoma Hepatocelular/metabolismo , Regulação para Baixo , Feminino , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade
14.
Hepatogastroenterology ; 59(119): 2104-11, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23435129

RESUMO

BACKGROUND/AIMS: This study was to evaluate and compare the clinical and pathological characteristics and patient outcomes after hepatic resection for different stages of HCC according to the Barcelona Clinic Liver Cancer (BCLC) classification system. METHODOLOGY: Three hundred and sixteen primary hepatectomies for HCC were divided into stage 0-c, according to BCLC classification. The clinicopathological variables of the patients in each group were compared statistically. RESULTS: There were significant differences in the incidence of capsular invasion, α-fetoprotein, blood loss, blood transfusion and tumor related number among each of the stage 0-C, respectively (p<0.05). Disease-free survival was influenced by histopathological grade (p=0.000), tumor capsule (p=0.015), tumor related number (p=0.000) and BCLC (p=0.000). Overall survival was influenced by histopathological grade (p=0.000), tumor capsule (p=0.035), tumor related number (p=0.005), cirrhosis (p=0.000) and BCLC (p=0.000). CONCLUSIONS: HCC in stage 0 and A were closely correlated with a better prognosis, which reflected the relatively benign pathobiological features of HCC at an early developmental stage. In comparison, HCC in stages B and C exhibited a tendency towards a more aggressive phenotype. Our findings suggest that stage B classification is optimal for estimating the biological behavior and clinical prognosis of patients undergoing partial hepatectomy for early stage HCC.


Assuntos
Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/cirurgia , Hepatectomia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Transfusão de Sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/mortalidade , Distribuição de Qui-Quadrado , Intervalo Livre de Doença , Feminino , Hepatectomia/efeitos adversos , Hepatectomia/mortalidade , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , alfa-Fetoproteínas/análise
15.
Mol Cell Endocrinol ; 543: 111543, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34995680

RESUMO

Nuclear receptor farnesoid X receptor (FXR) is generally considered a cell protector of enterohepatic tissues and a suppressor of liver cancer and colorectal carcinoma (CRC). Loss or reduction of FXR expression occurs during carcinogenesis, and the FXR level is inversely associated with the aggressive behaviors of the malignancy. Global deletion of FXR and tissue-specific deletion of FXR display distinct effects on tumorigenesis. Epigenetic silencing and inflammatory context are two main contributors to impaired FXR expression and activity. FXR exerts its antitumorigenic function via the following mechanisms: 1) FXR regulates multiple metabolic processes, notably bile acid homeostasis; 2) FXR antagonizes hepatic and enteric inflammation; 3) FXR impedes aberrant activation of some cancer-related pathways; and 4) FXR downregulates a number of oncogenes while upregulating some tumor suppressor genes. Restoring FXR functions via its agonists provides a therapeutic approach for patients with liver cancer and CRC. However, an in-depth understanding of the species-specific pharmacological effects is a prerequisite for assessing the clinical safety and efficacy of FXR agonists in human cancer treatment.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Receptores Citoplasmáticos e Nucleares/metabolismo , Ácidos e Sais Biliares/metabolismo , Neoplasias Colorretais/metabolismo , Humanos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Receptores Citoplasmáticos e Nucleares/genética
16.
Waste Manag ; 139: 105-115, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34959086

RESUMO

In this study, the distribution of precious metals in waste printed circuit boards was investigated and the economic value of recycling was assessed. Contacts of pins, slots, interfaces and the board surface in waste printed circuit boards were analyzed, and three types of precious metals were detected. The content of gold, silver and palladium ranged from 179.86 mg/kg to 3694.51 mg/kg, 809 mg/kg to 12320.51 mg/kg and 96.25 mg/kg to 117.49 mg/kg, respectively. Gold was distributed wildly in contacts of many slots and all interfaces, while contacts of only two interfaces (the cable and USB) contained palladium. The highest content of Au was found in contacts of the cable. Silver mainly concentrated on pins (metal foil contacts) of electronic components and its highest content was found in microchips. The economic value of recyclable precious metals in 1 t waste printed circuit boards was up to 2292.94 dollars, of which Au contributed 98%. This study indicates the prominent economic benefits of precious metal recovery from waste printed circuit boards. Moreover, the scientific information provide guidance for the directional and accurate recovery of precious metals from waste printed circuit boards.


Assuntos
Resíduo Eletrônico , Resíduo Eletrônico/análise , Ouro , Paládio , Reciclagem , Prata
17.
Chemosphere ; 309(Pt 2): 136656, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36191768

RESUMO

The elimination of volatile organic compounds (VOCs) via vacuum ultraviolet (VUV) photolysis is greatly limited by low removal efficiency and gaseous byproducts generation, while photocatalytic oxidation of VOCs suffers from catalytic deactivation. Herein, a coupled process of gaseous VUV photolysis with aqueous photocatalytic oxidation with P25 as the catalyst was firstly proposed for efficient aromatic VOCs removal (VUV/P25). The removal efficiency of toluene reached 86.2% in VUV/P25 process, but was only 33.6% and 58.1% in alone gaseous VUV photolysis and aqueous ultraviolet photocatalytic oxidation (UV/P25) process, respectively. Correspondingly, the outlet CO2 concentration in VUV/P25 process reached 132 ppmv. Toluene was firstly destructed by high-energy photons generated from gaseous VUV photolysis, resulting in its incomplete oxidation to form soluble intermediates including acids, aldehydes, esters. These soluble intermediates would be further degraded and mineralized into CO2 in subsequent aqueous UV/P25 process. Notably, the concentrations of intermediates in VUV/P25 were much lower than those in VUV photolysis, indicating the synergy effect of VUV photolysis and UV/P25 process. The stability tests proved that VUV/P25 process maintained an excellent toluene degradation performance and P25 did not suffer from catalytic deactivation. In addition to toluene, the VUV/P25 system also achieved the efficient and sustainable degradation of styrene and chlorobenzene, suggesting its good application prospect in industrial VOCs treatment. This study proposes an efficient and promising strategy for deep oxidation of multiple aromatic VOCs in industries.


Assuntos
Compostos Orgânicos Voláteis , Fotólise , Vácuo , Dióxido de Carbono , Raios Ultravioleta , Tolueno/análise , Oxirredução , Gases , Água , Clorobenzenos , Aldeídos , Estirenos
18.
Environ Pollut ; 279: 116862, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33744632

RESUMO

Liming is a safe and effective remediation practice for Cd contaminated acid paddy soil. The fate of Cd can also be strongly influenced by redox chemistry of sulfur. But it is unclear if, to what extent and how the combination of liming and sulfur mediation could further control Cd uptake by paddy rice. A rice cultivation pot experiment was conducted to evaluate the impact of different sulfur forms (S0 and SO42- in K2SO4) on the solubility, uptake and accumulation of Cd in the soil-paddy rice system and how liming and reducing organic carbon mediate the process. Results showed that under neutral soil circumstances achieved by liming, co-application of K2SO4 and glucose significantly reduced brown rice Cd by 33%, compared to liming alone. They made it more readily for Cd2+ to be precipitated into CdS/CdS2 or co-precipitate with newly formed FeS/FeS2/iron oxides. The higher pH balancing capability of K2SO4 as well as liming kept the newly formed sulfide or iron containing minerals negatively charged to be more prone to adsorb Cd2+, that kept the porewater Cd2+ the lowest among all the treatments. Individual K2SO4 showed significant promoting effect on soil Cd solubility due to SO42- chelation effect. Furthermore, K2SO4 had much weaker inhibiting effect on Cd translocation from root to grain, it showed no significant attenuating effect on brown rice Cd. S0 containing treatments displayed weaker or no attenuating effect on brown rice Cd due to its strong soil acidification effect. On the basis of liming, organic carbon induced sulfur (K2SO4) mediation showed great application potential for safe production on large areas of acid paddy soil contaminated by Cd.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Carbono , Óxidos , Solo , Poluentes do Solo/análise , Solubilidade , Enxofre
19.
Water Res ; 188: 116549, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152588

RESUMO

The UV/chlorine process is efficient for the abatement of micropollutants; yet, the formation of disinfection by-products (DBPs) and the toxicity can be altered during the treatment. This study investigated effluent organic matter characterization, DBP formation and toxicity alteration after the UV/chlorine treatment of wastewater; particularly, typical water matrix components in wastewater, namely, ammonia and bromide, were studied. The raw wastewater contained low levels of ammonia (3 µM) and bromide (0.5 µM). The UV/chlorine treatment efficiently eliminated 90 - 94% of fluorescent components. Compared with chlorination alone, a 20 min UV/chlorine treatment increased the formation of trihalomethanes (THMs), haloacetic acids (HAAs), chloral hydrate (CH), haloacetonitriles (HANs), trichloronitromethane (TCNM) and haloacetamides (HAcAms) by 90 - 508%. In post-chlorination after the UV/chlorine treatment, the formation of CH, HANs, TCNM and HAcAms increased by 77 - 274%, whereas the formation of both THMs and HAAs increased slightly by 11%. Meanwhile, the calculated cytotoxicity and genotoxicity of DBPs increased considerably after the UV/chlorine treatment and in post-chlorination, primarily due to the increased formation of HAAs and nitrogenous DBPs (N-DBPs). However, the acute toxicity of the wastewater to Vibrio fischeri and genotoxicity determined by the umu test decreased by 19% and 76%, respectively, after the 20 min UV/chlorine treatment. An additional 200 µM ammonia decreased the formation of all detected DBPs during the UV/chlorine treatment and 24 h post-chlorination, except that TCNM formation increased by 11% during post-chlorination. The acute toxicity of wastewater spiked with 200 µM ammonia was 32% lower than that of raw wastewater after the UV/chlorine treatment, but the genotoxicity was 58% higher. The addition of 1 mg/L bromide to the UV/chlorine process dramatically increased the formation of brominated DBPs and the overall calculated cytotoxicity and genotoxicity of DBPs. However, the acute toxicity and genotoxicity of the wastewater decreased by 7% and 100%, respectively, when bromide was added to the UV/chlorine treatment. This study illuminated that UV/chlorine treatment can decrease acute and geno- toxicities of wastewater efficiently.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Amônia , Brometos , Cloro , Desinfetantes/toxicidade , Desinfecção , Halogenação , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
20.
Front Med (Lausanne) ; 8: 735318, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34859005

RESUMO

Purpose: To evaluate the treatment solutions and effectiveness of intravitreal ranibizumab (RBZ) or conbercept in patients with wet age-related macular degeneration (wAMD) in a real-life setting in China. Methods: The medical records of 368 patients with wAMD who started RBZ or conbercept treatment between 1 May 2014 and 30 April 2018 were evaluated. All patients were defined on fundus angiography at baseline to determine the subtype of AMD (PCV or CNV). We report visual acuity (VA) and central retinal thickness (CRT) measurements at baseline and 12 months. Results: The average number of anti-VEGF injections was 2.1 ± 1.2. The BCVA improvement of these two groups was similar with a difference of 1.00 letter (95% CI: -1.4~3.4, p = 0.8505). At the end of the study, a BCVA increase of at least 5 letters was determined to be a satisfactory efficacy endpoint. Several factors were related to the possible improvement in the satisfactory efficacy endpoint, including female sex (OR 2.07, 95% CI 1.22~3.51), number of injections (OR 1.40, 95% CI 1.12~1.75) and VA change at the first month (OR 13.75, 95% CI 7.41~25.51). Additionally, some factors were related to the possible reduction in the satisfactory efficacy endpoint, including diabetes (OR 0.27, 95% CI 0.10~0.73) and disease history (OR 0.75, 95% CI 0.57~0.98). Conclusion: Our study demonstrates that anti-VEGF drugs can effectively improve BCVA and reduce CRT in AMD patients. Sex, number of injections, VA change at the first month, diabetes and disease history are the most important factors affecting visual acuity.

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