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1.
Int J Med Sci ; 21(10): 1814-1823, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113885

RESUMEN

Background: BMS-1166, a PD-1/PD-L1 inhibitor, inhibits the binding of PD-L1 to PD-1, restores T cell function, and enhances tumor immune response. However, mutations in the tumor suppressor or impaired cellular signaling pathways may also lead to cellular transformation. In this study, the SW480 and SW480R cell lines were used as the model to elucidate the treatment with BMS-1166, BEZ235, and their combination. Methods: MTT and colony-formation assays were used to evaluate cell proliferation. Wound-healing assay was used to assess cell migration. Cell cycle and apoptosis were analyzed by flow cytometry. The phosphorylation level of the key kinases in the PI3K/Akt/mTOR and MAPK pathways, PD-L1, and the protein levels related to the proliferation, migration, and apoptosis were assessed using western blotting. Results: BEZ235 enhanced BMS-1166-mediated cell proliferation and migration inhibition in SW480 and SW480R cells and promoted apoptosis. Interestingly, the downregulation of the negative regulator PTEN raised the PD-L1 level, which was abolished by the inhibition of Akt. BMS-1166 promoted PI3K, Akt, mTOR, and Erk phosphorylation. However, the combination of BEZ235 with BMS-1166 suppressed the expression of PI3K, p-Akt, p-mTOR, and p-Erk in SW480 and SW480R cells compared to BMS-1166 or BEZ235 single treatment by inhibiting the binding of PD1 to PD-L1. Conclusions: PD-1 binds to PD-L1 and activates the PI3K/mTOR and MAPK pathways, which might be the molecular mechanism of acquired resistance of CRC to BMS-1166. The combination of the two drugs inhibited the phosphorylation of PI3K, Akt, and Erk in the PI3K/mTOR and MAPK pathway, i.e., BEZ235 enhanced the BMS-1166 treatment effect by blocking the PI3K/mTOR pathway and interfering with the crosstalk of the MAPK pathway. Therefore, these findings provide a theoretical basis for BMS-1166 combined with BEZ235 in the trial treatment of colorectal cancer.


Asunto(s)
Apoptosis , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales , Imidazoles , Inhibidores de las Quinasa Fosfoinosítidos-3 , Quinolinas , Serina-Treonina Quinasas TOR , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inhibidores , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Sinergismo Farmacológico , Imidazoles/farmacología , Inhibidores mTOR/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Quinolinas/farmacología , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores
2.
Chaos ; 34(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38502966

RESUMEN

In this paper, we focus on the localized rational waves of the variable-coefficient Heisenberg spin chain equation, which models the local magnetization in ferromagnet with time-dependent inhomogeneous bilinear interaction and spin-transfer torque. First, we establish the iterative generalized (m,N-m)-fold Darboux transformation of the Heisenberg spin chain equation. Then, the novel localized rational solutions (LRSs), rogue waves (RWs), periodic waves, and hybrid wave structures on the periodic, zero, and nonzero constant backgrounds with the time-dependent coefficients α(t) and ß(t) are obtained explicitly. Additionally, we provide the trajectory curves of magnetization and the variation of the magnetization direction for the obtained nonlinear waves at different times. These phenomena imply that the LRSs and RWs play the crucial roles in changing the circular motion of the magnetization. Finally, we also numerically simulate the wave propagations of some localized semi-rational solutions and RWs.

3.
Pestic Biochem Physiol ; 199: 105804, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38458671

RESUMEN

Chemical fertilizer and pesticide are necessary in agriculture, which have been frequently used, sometimes even at the same time or in combination. To understand the interactions of them could be of significance for better use of these agrochemicals. In this study, the influence of chemical fertilizers (urea, potassium sulfate, ammonium sulfate and superphosphate) on the control efficacy and environmental behavior of abamectin was investigated, which could be applied in soil for controlling nematodes. In laboratory assays, ammonium sulfate at 1 and 2 g/L decreased the LC50 values of abamectin to Meloidogyne incognita from 0.17 mg/L to 0.081 and 0.043 mg/L, indicating it could increase the contact toxicity. In greenhouse trial, ammonium sulfate at 1000 mg/kg increased the control efficacy of abamectin by 1.37 times. Meanwhile, the combination of abamectin with ammonium sulfate could also promote the tomato seedling growth as well as the defense-related enzyme activity under M. incognita stress. The persistence and mobility of abamectin in soil were significantly elevated by ammonium sulfate, which could prolong and promote the control efficacy against nematodes. These results could provide reference for reasonable use of abamectin and fertilizers so as to increase the control efficacy and minimize the environmental risks.


Asunto(s)
Fertilizantes , Ivermectina/análogos & derivados , Tylenchoidea , Animales , Suelo , Sulfato de Amonio
4.
Ann Hematol ; 102(8): 2257-2265, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37311880

RESUMEN

Acquired thrombotic thrombocytopenic purpura (aTTP) is a fatal hematologic disease. Despite the currently high standards of care, some patients who develop refractory or recurrent disease still have a poor prognosis. Although N-acetylcysteine (NAC) is recommended for the treatment of aTTP, its use in aTTP treatment is still controversial. We aimed to evaluate the association of NAC with mortality in patients with aTTP. This was a retrospective cohort study of patients with aTTP with in-hospital mortality as the primary outcome and time to platelet recovery and neurological recovery as secondary outcomes. We used multifactorial COX regression analysis to check for an association of NAC with mortality. Moreover, we performed a sensitivity analysis check the stability of our results. Finally, 89 patients with aTTP were enrolled. After adjusting for potential confounders, we found NAC to be associated with 75% lower in-hospital mortality (HR = 0.25, 95% CI = 0.1-0.64). The results of sensitivity analyses performed remained stable as the risk of in-hospital mortality in patients reduced in patients with comorbid neurological symptoms (HR = 0.23, 95% CI = 0.06-0.89). However, NAC use did not affect the time to platelet recovery (HR = 1.19, 95% CI = 0.57-2.5) or neurological recovery (HR = 0.32, 95% CI = 0.08-1.25) in patients with aTTP. NAC treatment reduces in-hospital mortality in patients with aTTP but does not shorten the time to platelet recovery or neurological recovery.


Asunto(s)
Púrpura Trombocitopénica Trombótica , Humanos , Adulto , Púrpura Trombocitopénica Trombótica/diagnóstico , Acetilcisteína/uso terapéutico , Estudios Retrospectivos , Estudios de Cohortes , Mortalidad Hospitalaria , Intercambio Plasmático
5.
Helicobacter ; 28(3): e12973, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37017239

RESUMEN

BACKGROUND: Helicobacter pylori bacteremia is rare and difficult to make a definite diagnosis. CASE PRESENTATION: This is a 40-year-old woman represented as fever and unconsciousness accompanied by tics. She was diagnosed as Helicobacter pylori bacteremia and received emergency endotracheal intubation and antibiotics. Her symptoms resolved and she was discharged from ICU at the sixth day. CONCLUSIONS: Helicobacter pylori bacteremia is rare and hard to identify. Varied clinical manifestations leading to more difficult to make a definite diagnosis.


Asunto(s)
Bacteriemia , Infecciones por Helicobacter , Helicobacter pylori , Helicobacter , Humanos , Femenino , Adulto , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/diagnóstico , Bacteriemia/diagnóstico , Convulsiones/complicaciones , Inconsciencia/complicaciones
6.
Environ Sci Technol ; 57(40): 14881-14891, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37749806

RESUMEN

Thyroid dysfunction has become a serious public health problem, which is considered a trigger of nonalcoholic fatty liver disease (NAFLD). Pesticide exposure could contribute to thyroid dysfunction and NAFLD, but the relationship between these factors remains unclear. In this study, the effects of subchronic famoxadone exposure on thyroid and liver at no observed adverse effect level (NOEL) related concentrations were investigated using in vivo, in vitro, and in silico models. Famoxadone caused hepatic steatosis, lipid metabolism disorder, and liver oxidative stress and induced NAFLD in male mice. The suppression of hepatic fatty acid ß-oxidation was the key factor of NAFLD, which was highly associated with hypothalamic-pituitary-thyroid (HPT) axis hormones disorder. Famoxadone disrupted thyroid hormone biosynthesis by causing thyroid follicle aberrations and abnormal HPT axis-related gene expression. In vitro studies confirmed that famoxadone inhibited the transport of thyroxine (T4) into hepatocytes and the conversion of T4 to triiodothyronine (T3). In silico studies verified that famoxadone interfered with the binding of thyroid hormones to proteins mediating thyroid hormone transport, conversion, and activation. This study comprehensively reported the association between NAFLD and thyroid dysfunction caused by famoxadone, providing new perspectives for the health risk evaluation of pesticides with a similar structure in mammals.

7.
Biochem Biophys Res Commun ; 595: 1-6, 2022 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-35091108

RESUMEN

Farnesoid X receptor (FXR) is a bile acid-related nuclear receptor and is considered a promising target to treat several liver disorders. Cilofexor is a selective FXR agonist and has already entered phase III trials in primary sclerosing cholangitis (PSC) patients. Pruritis caused by cilofexor treatment is dose dependent. The binding characteristics of cilofexor with FXR and its pruritogenic mechanism remain unclear. In our research, the affinity of cilofexor bound to FXR was detected using an isothermal titration calorimetry (ITC) assay. The binding mechanism between cilofexor and FXR-LBD is explained by the cocrystal structure of the FXR/cilofexor complex. Structural models indicate the possibility that cilofexor activates Mas-related G protein-coupled receptor X4 (MRGPRX4) or G protein-coupled bile acid receptor 1 (GPBAR1), leading to pruritus. In summary, our analyses provide a molecular mechanism of cilofexor binding to FXR and provide a possible explanation for the dose-dependent pruritis of cilofexor.


Asunto(s)
Azetidinas/química , Ácidos Isonicotínicos/química , Simulación del Acoplamiento Molecular , Dominios Proteicos , Receptores Citoplasmáticos y Nucleares/química , Azetidinas/metabolismo , Azetidinas/farmacología , Ácidos y Sales Biliares/química , Ácidos y Sales Biliares/metabolismo , Sitios de Unión , Unión Competitiva , Calorimetría/métodos , Cristalización , Humanos , Enlace de Hidrógeno , Ácidos Isonicotínicos/metabolismo , Ácidos Isonicotínicos/farmacología , Isoxazoles/química , Isoxazoles/metabolismo , Isoxazoles/farmacología , Ligandos , Estructura Molecular , Receptores Citoplasmáticos y Nucleares/agonistas , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo
8.
Environ Sci Technol ; 56(12): 7883-7894, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35593893

RESUMEN

Antibiotics could enter farmlands through sewage irrigation or manure application, causing combined pollution with pesticides. Antibiotics may affect the environmental fate of pesticides and even increase their bioavailability. In this study, the influence of monensin on the degradation, toxicity, and availability of atrazine in soil-earthworm microcosms was investigated. Monensin inhibited the degradation of atrazine, changed the metabolite patterns in soil, and increased the bioavailability of atrazine in earthworms. Atrazine and monensin had a significant synergistic effect on earthworms in the acute toxic test. In long-term toxicity tests, co-exposure of atrazine and monensin also led to worse effects on earthworms including oxidative stress, energy metabolism disruption, and cocoon production compared to single exposure. The expression of tight junction proteins was down-regulated significantly by monensin, indicating that the intestinal barrier of earthworms was weakened, possibly causing the increased bioavailability of atrazine. The expressions of heat shock protein 70 (Hsp70) and reproductive and ontogenetic factors (ANN, TCTP) were all downregulated in binary exposure, indicating that the resilience and cocoon production of earthworms were further weakened under combined pollution. Monensin disturbed the energy metabolism and weakened the intestinal barrier of earthworms. These results showed that monensin increased the risks of atrazine in agricultural areas.


Asunto(s)
Atrazina , Oligoquetos , Plaguicidas , Contaminantes del Suelo , Animales , Antibacterianos/farmacología , Atrazina/toxicidad , Monensina/farmacología , Monensina/toxicidad , Plaguicidas/metabolismo , Suelo , Contaminantes del Suelo/metabolismo
9.
Environ Sci Technol ; 55(3): 1419-1435, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33433212

RESUMEN

Ionic liquids (ILs) as novel functional desulfurization materials have attracted increasing attentions. Metal-based ionic liquids (MILs) are classified into three types of metal chloride ILs, metal oxide ILs, and metal complex ILs based on the definition and basic structure of MILs in this critical review. On the basis of the properties of ILs such as structure designability, super dissolution performance, good thermal and chemical stability, nonflammability, and wide electrochemical window, MILs exhibit unique advantages on hydrophobicity, oxidation performance, and Brönsted-Lewis acidity. Therefore, MILs possess both the absorption and oxidation centers for the intramolecular adsorption and oxidation to improve the oxidative desulfurization (ODS) process. During the novel nonaqueous wet oxidative desulfurization process (Nasil), H2S can be oxidized into elemental sulfur with hydrophobic MILs, which can be regenerated by oxygen for recycle, to solve the problems of low sulfur capacity, low sulfur quality, and severe secondary pollution in the aqueous Lo-Cat wet oxidative desulfurization process. Another outstanding feature of MILs in ODS is biomimetic catalysis, which has the function of activating molecular oxygen and improving the oxidation performance. Metal oxide ILs and metal complex ILs are used in combination with hydrogen peroxide or oxygen with the existing water to generate a Fenton-like reaction to convert hydrophobic organic sulfur or SO2 into hydrophilic sulfoxide/sulfone or sulfur acid, respectively. However, the corrosion of Cl- to the equipment and emulsification phenomenon in the extraction process of sulfoxide/sulfone separation still need further study. Furthermore, the promising strategies to construct highly efficient and green desulfurization processes for large-scale applications are provided.


Asunto(s)
Líquidos Iónicos , Metales , Oxidación-Reducción , Estrés Oxidativo , Azufre
10.
Int J Med Sci ; 18(6): 1456-1464, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33628103

RESUMEN

Background: Sorafenib, an oral multi-kinase inhibitor of rapidly accelerated fibrosarcoma; vascular endothelial growth factor receptor-2/3, platelet-derived growth factor receptor, c-Kit, and Flt-3 signaling, is approved for treatment of advanced hepatocellular carcinoma (HCC). However, the benefit of sorafenib is often diminished because of acquired resistance through the reactivation of ERK signaling in sorafenib-resistant HCC cells. In this work, we investigated whether adding LY3214996, a selective ERK1/2 inhibitor, to sorafenib would increase the anti-tumor effectiveness of sorafenib to HCC cells. Methods: The Huh7 cell line was used as a cell model for treatment with sorafenib, LY3214996, and their combination. Phosphorylation of the key kinases in the Ras/Raf/MAPK and PI3K/Akt pathways, protein expression of the cell cycle, and apoptosis migration were assessed with western blot. MTT and colony-formation assays were used to evaluate cell proliferation. Wound-healing assay was used to assess cell migration. Cell cycle and apoptosis analyses were conducted with flow cytometry. Results: LY3214996 decreased phosphorylation of the Ras/Raf/MAPK and PI3K/Akt pathways, including p-c-Raf, p-P90RSK, p-S6K and p-eIF4EBP1 activated by sorafenib, despite increased p-ERK1/2 levels. LY3214996 increased the anti-proliferation, anti-migration, cell-cycle progression, and pro-apoptotic effects of sorafenib on Huh7R cells. Conclusions: Reactivation of ERK1/2 appears to be a molecular mechanism of acquired resistance of HCC to sorafenib. LY3214996 combined with sorafenib enhanced the anti-tumor effects of sorafenib in HCC. These findings form a theoretical basis for trial of LY3214996 combined with sorafenib as second-line treatment of sorafenib-resistant in advanced HCC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Hepáticas/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/farmacología , Pirroles/farmacología , Sorafenib/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Sinergismo Farmacológico , Humanos , Neoplasias Hepáticas/patología , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirazoles/uso terapéutico , Pirroles/uso terapéutico , Sorafenib/uso terapéutico
11.
Scand J Clin Lab Invest ; 81(6): 494-501, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34325600

RESUMEN

The objective of this work is to develop and verify the analytical performance of a chemiluminescence immunoassay for the specific sequence ß-carboxy-terminal cross-linking telopeptide of type I collagen (ß-CTX) in human serum. Two specific monoclonal antibodies (mAb-8A03 and mAb-3D12) with high affinity for ß-CTX were selected, and, under optimized conditions, a chemiluminescence immunoassay method (CLIA) for ß-CTX was established. The CLIA of ß-CTX detected ß-CTX in a wide range of 2.0-6000 ng/L. The recovery rate in serum is 95-105%, the specificity is high, and the cross-reaction rate with common easily interfering substances is low (not more than 0.01%). The CLIA correlates well with Roche electrochemiluminescence immunoassay (ECLIA), with a correlation coefficient of 0.9551, which fully meets the requirements of clinical analysis. The developed ß-CTX CLIA kit has high sensitivity and good stability. It has the same performance as the commercial Roche ECLIA kit and can be applied clinically.


Asunto(s)
Colágeno Tipo I/sangre , Mediciones Luminiscentes/métodos , Péptidos/sangre , Anticuerpos/metabolismo , Humanos , Inmunoensayo , Límite de Detección , Fenómenos Magnéticos , Tamizaje Masivo , Microesferas , Estándares de Referencia , Sensibilidad y Especificidad
12.
Environ Sci Technol ; 54(4): 2218-2227, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-31961661

RESUMEN

Carbonyl compounds are an important class of by-products that are generated in disinfection reactions. These chemicals are ingredients contributing to toxicology in the drinking water system, the compositions and structures of which are worthy of attention. In this study, a chemical derivatization method based on simultaneous light/heavy isotope labeling was established for general recognition of carbonyl compounds and carbonyl disinfection by-products (DBPs) as per the humic substance reference standard (Suwannee river fulvic acid II, SRFA) before and after ozonation, chlorination, and chloramination. Decomposition of macromolecular components into polar carbonyl species was observed to be the most prominent pathway in ozone treatment due to the efficient reactivity of ozone with phenols and alkoxy aromatic rings. As a result, alteration of molecular characteristics was noticed. For instance, ozone-induced carbonyl DBPs in the highly oxygenated compound classes (0.67 ≤ O/C ≤ 1.2, 0.6 < H/C ≤ 1.5) possessed higher O/C but contained less oxygen numbers and carbon numbers. Cl/Br-carbonyl-DBPs were identified after chlorination and chloramination, and I-carbonyl-DBPs were found in ozone and chloramine treatments. Several major halogenated carbonyl homologues were further recognized, including halogenated 4-oxobutenoic acid analogues, halogenated 2,5-dioxohex-3-enoic acid analogues, and halogenated 4-cyclopentene-1,3-diones analogues. These findings illustrate the presence of abundant carbonyl DBPs in water disinfection, and hence their impacts on human health deserve further investigation.


Asunto(s)
Desinfectantes , Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Desinfección , Halogenación
13.
Environ Sci Technol ; 54(20): 12949-12958, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-32966056

RESUMEN

With diminishing pristine water, wastewater-affected waters that contain complex anthropogenic compounds are becoming important sources of drinking water and the compounds will inevitably react with disinfectants to form disinfection byproducts (DBPs). Secondary amines such as diphenylamine (DPA) analogues are considered as potential precursors of N-nitrosamines. In this study, an in situ 14N/15N-labeling and screening workflow was used to systematically investigate the formation of nitrogenous DBPs (N-DBPs) and putative reaction pathways. Twenty-four pairs of N-DBPs were generated and identified from chloramination of DPA through two main pathways, in which chloramines reacted with the amino and phenyl functional groups to form N-nitrosodiphenylamine and monochlorinated 5,10-dihydro-phenazine (Cl-DiH-Phe), respectively. Cl-DiH-Phe could further produce phenazine and the coupling products with another DPA molecule. Selective N-DBP formation was pH and dose-dependent, and the same reactions were observed for additional two aromatic DPA analogues. Effects of alkyl substituents on the formation pathways were investigated using a series of dialkyl and N-alkyl aromatic analogues. Only the amino pathway to form nitrosamines was noticed for dialkyl amines, nevertheless, both the main reactions occurred for N-alkyl aromatic amines. These findings suggested that the reaction with chloramines through a phenyl pathway was likely to be crucial for novel nitrogenous heterocyclic byproducts.


Asunto(s)
Desinfectantes , Nitrosaminas , Contaminantes Químicos del Agua , Purificación del Agua , Aminas , Cloraminas , Desinfección , Halogenación , Nitrógeno , Contaminantes Químicos del Agua/análisis
14.
Mikrochim Acta ; 186(12): 825, 2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31754860

RESUMEN

Magnetic partially carbonized cellulose nanocrystals (MPC-CNC) were obtained by sulfuric acid treatment of microcrystalline cellulose (MCC) and then loaded with magnetic Fe3O4 nanoparticles. The material is shown to be a viable material for magnetic solid phase extraction of triazine and triazole pesticides from water. The pesticides (specifically: simazine, ametryn, prometryn, terbutryn, atrazine, triadimenol, epoxiconazole, myclobutanil, triadimefon and tebuconazole) were quantified by ultra HPLC in tandem with a triple quadrupole mass spectrometry (UHPLC-MS/MS). The effects of NaCl concentration, amount of adsorbent, vortex time, sample volume and pH value on extraction efficiency were optimized by Plackett-Burman design and Box-Behnken design methods. Under the optimal conditions, the method shows the following figures of merit: (a) Linear responses in the range from 0.02-10 µg L-1; (b) detection limits between 2.2 to 6.1 ng L-1 (for S/N = 3); (c) recoveries from spiked samples of 73.7-117.1% with relative standard deviations (RSDs) of 2.0-15.7%; and (d) an enrichment factor of 75. The method was successfully applied to the determination of the pesticides in five environmental water samples. Graphical abstract Schematic representation of the process of magnetic solid phase extracting pesticides in water using MPC-CNC. MCC-microcrystalline cellulose; PC-CNC- partially carbonized cellulose nanocrystals; MPC-CNC-magnetic partially carbonized cellulose nanocrystals.

16.
Org Biomol Chem ; 15(33): 6901-6904, 2017 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-28786465

RESUMEN

A solvent controlled regioselective metal-free synthesis of iodo-substituted N-heterocycles has been developed. This protocol undergoes a cascade iodination/cyclization/oxidation/aromatization pathway to afford multi-halogenated quinolines from readily available propargylamines under mild conditions.

17.
Ecotoxicol Environ Saf ; 141: 93-97, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28319864

RESUMEN

Bullfrog, as a kind of amphibians, can be easily exposed to varied pollutants in the environment for the reason of its habitats and highly permeable skin. We investigated the degradation kinetics and residues of α-cypermethrin in bullfrog by two different methods of administration for the environmental monitoring the behavior of one of the most used pesticides in the amphibians. The oral administration and water exposure of α-cypermethrin on bullfrog was studied in this work. α-Cypermethrin and its main metabolites of cis-3-(2',2-dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (cis-DCCA) and 3-phenoxybenzoic acid (3-PBA), which have been determined that having correlation with a number of epidemic diseases, were detected simultaneously. The method for residue analysis in the bullfrog's organs was validated. The average recoveries for α-cypermethrin were ranged from 71.7% to 100.3% and the limit of quantification was 0.005mg/kg. The average recoveries of its metabolites at levels between 0.002 and 0.5mg/kg ranged between 77.9% and 102.4% with a limit of quantification of 0.002mg/kg. Furthermore, the enantiomers of α-cypermethrin were separated on gas chromatograph (GC) equipped with a chiral column of BGB-172 and the metabolites were detected by gas chromatography (GC) after derivatization. After exposure of α-cypermethrin on bullfrog, the enantioselective degradation behavior was observed and its metabolites were detected in bullfrog tissues. The dynamic trends of α-cypermethrin and its metabolites were fitted to a two-compartment model except 3-PBA fitting to one-compartment model in skin. Concentration of α-cypermethrin and its metabolites in bullfrog's organs increased and reached an equilibrium state during water exposure of α-cypermethrin. Liver and kidney were the major organs for α-cypermethrin and its metabolites retention in both experiments.


Asunto(s)
Monitoreo del Ambiente/métodos , Insecticidas/metabolismo , Piretrinas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Administración Oral , Animales , Benzoatos/análisis , Benzoatos/sangre , Benzoatos/metabolismo , Cromatografía de Gases , Insecticidas/análisis , Insecticidas/sangre , Riñón/efectos de los fármacos , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Especificidad de Órganos , Piretrinas/análisis , Piretrinas/sangre , Rana catesbeiana , Estereoisomerismo , Distribución Tisular , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/sangre
18.
Environ Sci Technol ; 50(11): 5695-701, 2016 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-27163366

RESUMEN

α-Hexachlorocyclohexane (α-HCH) is a chiral organochlorine pesticide that is often ubiquitously detected in various environmental matrices and may be absorbed by the human body via food consumption, with serious detriments to human health. In this study, enantioselective degradation kinetics and residues of α-HCH in laying hens were investigated after a single dose of exposure to the pesticide, whereas enantioselectivity and residues of α-HCH in eggs, droppings, and various tissues were investigated after long-term exposure. Meanwhile, montmorillonite (MMT), a feed additive with high capacity of adsorption, was investigated for its ability to remove α-HCH from laying hens. Most non-brain tissues enantioselectively accumulated (-)-α-HCH, while (+)-α-HCH was preferentially accumulated in the brain. The enantiomer fractions (EFs) in most tissues gradually decreased, implying continuous depletion of (+)-α-HCH in laying hens. After 30 days of exposure and 31 days of elimination, the concentration of α-HCH in eggs and tissues of laying hens with MMT-containing feed was lower than that with MMT-free feed, indicating the removal effects of MMT for α-HCH in laying hens. The findings presented herein suggest that modified MMT may potentially be useful in reducing the enrichment of α-HCH in laying hens and eggs, thus lowering the risk of human intake of α-HCH.


Asunto(s)
Bentonita , Pollos/metabolismo , Alimentación Animal , Animales , Huevos , Femenino , Humanos , Hidrocarburos Clorados/metabolismo , Plaguicidas/metabolismo
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124889, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39116595

RESUMEN

Pesticide residues are currently a prominent concern for food safety, and the development of a rapid, convenient, and accurate method for detecting pesticide residues is crucial to ensure the quality of agricultural products. In this study, a small molecule fluorescent probe based on biphenyl disulfonic acid (BDSA) was designed and prepared, and a sensitive, specific, and rapid detection method for diquat (DQ) and paraquat (PQ) was developed. The fluorescent molecule (BDSA-NDA) was synthesized through amide reaction between BDSA and 1,8-naphthalic anhydride, which exhibited cyan fluorescence (480 nm) when excited at 305 nm in aqueous solution with a large Stokes shift (>150 nm). Diquat and paraquat were found to quench the fluorescence of the probe through internal filtration effect (IFE) and photoelectron transfer (PET). Moreover, diquat possessed a large conjugated structure that emitted fluorescence at 340 nm which was assembled into a pair of ratio fluorescence with BDSA-NDA. Under optimized experimental conditions, the developed method achieved detection limits of 0.003 mg/L for diquat and 0.202 mg/L for paraquat. Furthermore, it could identify paraquat doped in diquat formulations. Additionally, when applied to environmental water samples as well as rice and urine, this detection method demonstrated good recovery rates (water: 96.2-100.6 %, rice: 93.5-101.9 %, urine: 96-103.7 %), meeting actual sample detection requirements effectively. This work presents a novel approach for rapidly detecting diquat and paraquat residues which holds practical application value in areas such as pesticide residue analysis in foods, environmental or clinical samples.


Asunto(s)
Diquat , Colorantes Fluorescentes , Espectrometría de Fluorescencia , Diquat/análisis , Diquat/orina , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Espectrometría de Fluorescencia/métodos , Límite de Detección , Paraquat/análisis , Paraquat/orina , Contaminantes Químicos del Agua/análisis
20.
Environ Pollut ; 342: 122909, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38036092

RESUMEN

Microplastic is an emerging environmental pollutant with potential health risks. Recent studies have shown that microplastic could impair gut homeostasis in mammals. Although it has been widely demonstrated that gut dyshomeostasis could impact renal health through the gut-kidney axis, the effects of microplastic-induced gut dyshomeostasis on renal health and underlying mechanisms are still largely unknown. In the current work, we found that polystyrene microplastics (PS-MPs) treatment impaired the gut barrier, increased urinary complement-activated product C5a levels and renal C5aR expression, leading to chronic kidney disease-related symptoms in mice. Restoring the gut barrier using an antibiotic mixture effectively alleviated PS-MPs-induced kidney injury, indicating the involvement of the gut-kidney axis in PS-MPs-induced renal injury. Moreover, it also mitigated PS-MPs-induced alterations in urinary C5a levels and renal C5aR expression, suggesting that the renal C5a/C5aR pathway might be involved in PS-MPs' impacts on the gut-kidney axis. Further experiments using a C5aR inhibitor, PMX53, verified the vital role of renal C5a/C5aR pathway activation in the development of kidney injury induced by PS-MPs. Collectively, our results suggest that PS-MPs induce kidney injury in mice by impairing the gut barrier, increasing C5a levels, and ultimately activating the renal C5a/C5aR pathway, highlighting the crucial role of the gut-kidney axis in PS-MPs-induced kidney injury.


Asunto(s)
Microplásticos , Plásticos , Animales , Ratones , Microplásticos/toxicidad , Microplásticos/metabolismo , Plásticos/metabolismo , Poliestirenos/toxicidad , Poliestirenos/metabolismo , Riñón/metabolismo , Mamíferos
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