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1.
J Viral Hepat ; 30(5): 417-426, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36704832

RESUMO

Hepatocellular carcinoma (HCC) initiated by hepatitis B virus (HBV) infection is a complicated process. MiR-155 can alter the immune microenvironment to affect the host's anti-infective ability. This study investigated the mechanism by which miR-155 affects tumour-associated macrophage (TAM) polarization at a molecular level, thus affecting the malignant progression of HBV+ HCC. MiR-155 and TAM-related cytokine expression were analysed by qRT-PCR. The distribution of TAMs was detected by immunohistochemistry. The effect of the aberrant miR-155 expression on macrophage polarization was examined by flow cytometry. The targeted relationship was verified by dual-luciferase assay, and the protein level of src homology 2 domain-containing inositol polyphosphate 5-phosphatase 1 (SHIP1) was detected by western blot. The proliferation of HCC cells was examined by CCK-8 and colony formation assays. Invasion and migration of HCC cells were detected by transwell assay. In HBV+ HCC tissues, miR-155 was significantly highly expressed and the number of CD206-positive TAM (CD206+ TAM) and CD68-positive TAM (CD68+ TAM) were higher than those in HBV- HCC tissues. In addition, miR-155 overexpression significantly promoted M2-type macrophage polarization, whilst miR-155 silencing expression significantly promoted M1-type macrophage polarization. Besides, the miR-155/SHIP1 axis accelerated HCC cell invasion, proliferation and migration by inducing M2-type macrophage polarization. MiR-155 accelerates HCC cell proliferation, migration and invasion by targeting SHIP1 expression and inducing macrophage M2 polarization. This finding provides new insights into the development of novel therapeutic strategies for combatting HBV+ HCC and a new reference for exploring anti-tumour immunotherapy.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Vírus da Hepatite B/metabolismo , Neoplasias Hepáticas/patologia , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Hepatite B/complicações , Linhagem Celular Tumoral , Proliferação de Células , Microambiente Tumoral
2.
Drug Chem Toxicol ; 46(3): 423-429, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35266432

RESUMO

Tea is consumed widely around the world owing to its refreshing taste and potential health benefits. However, drinking tea is considered a major route for dietary aluminum exposure in areas where tea consumption is relatively large. To assess the health risk associated with drinking tea, the contamination level of aluminum was determined in 81 tea samples. The transfer rate of aluminum during tea brewing was investigated. Then based on the site-specific exposure parameters such as consumption data and body weight for six different subpopulations in Fujian, the exposure risks were estimated using a probabilistic approach. Results demonstrate that the contents of aluminum in green tea, white tea, oolong tea, and black tea were significantly different according to the one-way ANOVA analysis (p < 0.05). The transfer rate of aluminum were 32.6%, 31.6%, 26.3%, and 14% for white tea, black tea, oolong tea, and green tea, respectively. With respect to the oral reference dose, the exposure of inhabitants in Fujian to aluminum through drinking tea is under control (even at the 99th percentile).


Assuntos
Alumínio , Camellia sinensis , Chá , Peso Corporal , Povidona/análise
3.
Drug Chem Toxicol ; 45(2): 932-939, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32752890

RESUMO

The objective of this study was to evaluate the residues of 42 pesticides subject to public concern in Tieguanyin tea produced in Fujian, China. The presence of 42 pesticide residues in 90 Tieguanyin tea samples were determined. A total of 17 pesticides were detected. At least one pesticide residue was detected in 65 samples (72.2%). The detected pesticides imidacloprid, tolfenpyrad, bifenthrin, acetamiprid were found in 55.6%, 33.3%, 18.9% and 16.7% of samples, respectively. Pesticide residues in Tieguanyin tea varied significantly over the seasons and across the production regions. Based on data obtained, the health risks associated with long-term exposure to those pesticides were assessed and risks of detected pesticides were ranked. The hazard quotients (HQs) among the detected pesticides range from 5 × 10-8 for fenpropathrin to 3 × 10-4 for imidacloprid. The results demonstrated that despite a high occurrence of pesticide residues in Tieguanyin tea, residue levels observed could not be considered as a serious public health problem. The risk ranking scheme showed dicofol and thiacloprid were considered to pose a medium-risk. The suggestions for 17 detected pesticides used in Tieguanyin tea plantation were made, including those already banned from use in China (dicofol and methomyl), recommended for diminished use (thiacloprid and chlorpyrifos), and permitted use with considering the pre-harvest interval (13 other pesticides).


Assuntos
Resíduos de Praguicidas , Praguicidas , China , Contaminação de Alimentos/análise , Resíduos de Praguicidas/toxicidade , Praguicidas/análise , Medição de Risco/métodos , Chá/química
4.
Chemistry ; 26(25): 5619-5628, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-31985087

RESUMO

In this work, a latent energy-transfer process in traditional Eu3+ ,Tb3+ -doped phosphors is proposed and a new class of Eu3+ ,Tb3+ -doped Na4 CaSi3 O9 (NCSO) phosphors is presented which is enabled by luminescence decay dynamics that optimize the electron-transfer energy process. Relative to other Eu3+ ,Tb3+ -doped phosphors, the as-synthesized Eu3+ ,Tb3+ -doped NCSO phosphors show improved large-scale tunable emission color from green to red upon UV excitation, controlled by the Tb3+ /Eu3+ doping ratio. Detailed spectroscopic measurements in the vacuum ultraviolet (VUV)/UV/Vis region were used to determine the Eu3+ -O2- charge-transfer energy, 4f-5d transition energies, and the energies of 4f excited multiplets of Eu3+ and Tb3+ with different 4fN electronic configurations. The Tb3+ →Eu3+ energy-transfer pathway in the co-doped sample was systematically investigated, by employing luminescence decay dynamics analysis to elucidate the relevant energy-transfer mechanism in combination with the appropriate model simulation. To demonstrate their application potential, a prototype white-light-emitting diode (WLED) device was successfully fabricated by using the yellow luminescence NCSO:0.03Tb3+ , 0.05Eu3+ phosphor with high thermal stability and a BaMgAl10 O17 :Eu2+ phosphor in combination with a near-UV chip. These findings open up a new avenue to realize and develop multifunctional high-performance phosphors by manipulating the energy-transfer process for practical applications.

5.
BMC Endocr Disord ; 20(1): 51, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32299395

RESUMO

BACKGROUND: The relationship between betatrophin/ANGPTL8 and obesity has been investigated using body mass index (BMI); however, since BMI reflects overall adiposity rather than body fat distribution, it remains unclear whether fat deposition in different areas of the body affects betatrophin expression. Here, we investigated the correlation between circulating betatrophin levels and body fat distribution in patients with different glucose tolerance. METHODS: We performed a cross-sectional study in 128 participants with impaired glucose tolerance (IGT; n = 64) or normal glucose tolerance (NGT; n = 64). Circulating betatrophin levels were detected by enzyme-linked immunosorbent assay (ELISA). Body fat distribution (subcutaneous, visceral, and limb fat) was measured by magnetic resonance imaging (MRI) and a body fat meter. RESULTS: After controlling for age, sex, and BMI, betatrophin was correlated positively with visceral adipose tissue-to-subcutaneous adipose tissue ratio (VAT/SAT ratio; r = 0.339, p = 0.009) and negatively with body fat ratio (BFR; r = - 0.275, p = 0.035), left lower limb fat ratio (LLR; r = - 0.330, p = 0.011), and right lower limb fat ratio (RLR; r = - 0.288, p = 0.027) in the NGT group, with these correlations remaining after controlling for triglycerides. VAT/SAT ratio (standardized ß = 0.419, p = 0.001) was independently associated with serum betatrophin levels; however, betatrophin was not associated with body fat distribution variables in the IGT group. CONCLUSIONS: Circulating betatrophin levels correlated positively with VAT/SAT ratio and negatively with lower limb fat, but not with subcutaneous or upper limb fat, in individuals with normal glucose tolerance. Thus, betatrophin may be a potential biomarker for body fat distribution in individuals without glucose disorders.


Assuntos
Proteínas Semelhantes a Angiopoietina/sangue , Distribuição da Gordura Corporal , Intolerância à Glucose/sangue , Gordura Intra-Abdominal/diagnóstico por imagem , Hormônios Peptídicos/sangue , Gordura Subcutânea/diagnóstico por imagem , Tecido Adiposo/diagnóstico por imagem , Proteína 8 Semelhante a Angiopoietina , Estudos de Casos e Controles , Estudos Transversais , Extremidades , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
6.
Curr Microbiol ; 76(10): 1168-1174, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31263923

RESUMO

A Gram-negative, strictly aerobic, motile, rod-shaped bacterium with monopolar flagellum, designated as F51T, was isolated from the skin ulcer of farmed Murray cod sampled from Zhejiang Province, China. Strain F51T grew at 4-37 °C (optimal temperature, 28 °C), pH 5.0-8.5 (optimal pH, 7.5) and NaCl concentration of 0-6.0% (w/v) (optimal concentration, 2.0%). Phylogenetic analysis based on average nucleotide identity (76.2-78.4%) and in silico DNA-DNA hybridization (22.3-23.2%) values revealed that strain F51T forms a distinct lineage in the clade of genus Pseudomonas with less than 98.9% 16S rRNA gene sequence similarity to type strains of the genus and represents a novel species related most closely to Pseudomonas floridensis LMG 30013T. Three housekeeping genes (rpoB, rpoD and gyrB) of strain F51T were analysed to further confirm that the isolate is distinctly delineated from related Pseudomonas species. Chemotaxonomic analysis indicated that the sole respiratory quinone of strain F51T is Q-9; its predominant cellular fatty acids are C16:0, summed feature 3 (iso-C15:0 2-OH and/or C16:1ω7c), summed feature 8 (C18:1ω7c and/or C18:1ω6c) and C10:0 3-OH; and its major polar lipids consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, two unidentified glycolipids, three unidentified phospholipids and an unidentified aminophosphoglycolipid. This composition is typical of the chemotaxonomic attributes of Pseudomonas. Based on its phenotypic, chemotaxonomic and phylogenetic features, strain F51T is considered to represent a novel species for which the name Pseudomonas ovata sp. nov. is proposed. The type strain is F51T (= KCTC 62133T = MCCC 1K03458T).


Assuntos
Doenças dos Peixes/microbiologia , Perciformes/microbiologia , Filogenia , Pseudomonas/classificação , Pseudomonas/fisiologia , Animais , Aquicultura , Composição de Bases , China , DNA Bacteriano/genética , Genes Bacterianos/genética , Genoma Bacteriano/genética , Lipídeos/química , Hibridização de Ácido Nucleico , Pseudomonas/química , Pseudomonas/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
7.
Int J Syst Evol Microbiol ; 68(11): 3397-3403, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30272541

RESUMO

A yellow-pigmented, Gram-staining-negative, aerobic, non-motile and rod-shaped bacterium, designated strain F30T, was isolated from fresh water of a diseased farmed Murray cod with a profound ulceration pond in Zhejiang province, PR China. Growth was observed at NaCl concentrations of 0.5-3.5 % (w/v) (optimum, 1.5-2.0 %), temperatures of 10-35 °C (optimum, 28 °C) and pH 5.0-9.0 (optimum, 6.5). Phylogenetic analysis based on 16S rRNA gene sequences indicated that F30T represented a member of the genus Chryseobacterium, showing the highest similarity to Chryseobacterium jejuense DSM 19299T (99.0 %) and Chryseobacterium nakagawai NCTC 13529T (99.0 %), and less than 98.7 % similarity to other species of the genus Chryseobacterium with validly published names. The average nucleotide identity and in silico DNA-DNA hybridization values between F30T and the reference strains were 78.4-90.5 % and 2.6-42.5 %, respectively. The results of chemotaxonomic analysis indicated that the fatty acids, as well as the polar lipid profiles of F30T were similar to those of species of the genus Chryseobacterium, and the sole respiratory quinone was MK-6. On the basis of its phylogenetic, chemotaxonomic and phenotypic data, strain F30T represents a novel species, for which the name Chryseobacteriumaurantiacum sp. nov. is proposed. The type strain is F30T (=KCTC 62135T=MCCC 1K03457T).


Assuntos
Chryseobacterium/classificação , Filogenia , Lagoas/microbiologia , Microbiologia da Água , Animais , Aquicultura , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Chryseobacterium/genética , Chryseobacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Perciformes , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
Int J Syst Evol Microbiol ; 68(3): 905-910, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29458492

RESUMO

A taxonomic study was carried out on strain LW15T, which was isolated from the external lesions of diseased farmed Murray cod (Maccullochella peelii peelii) from an intensive culture pond. Cells of strain LW15T were Gram-negative, facultative-anaerobic, non-motile, and both coccobacillus- and bacillus-shaped. Growth was observed at NaCl concentrations of 0-2 % (w/v) (optimum, 0 %), 4-32 °C (optimum, 25-28 °C) and pH 5.0-9.0 (optimum, 7.0). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LW15T was affiliated to the genus Acinetobacter, showing the highest similarity to Acinetobacter guillouiae CIP 63.46T (97.7 %) and other Acinetobacter species with validly published names (93.5-97.6 %). Whole-genome sequencing and phylogeny reconstruction based on a core set of 1061 Acinetobacter genes indicated that strain LW15T was most closely related to the clade formed by A. guillouiae CIP 63.46T and Acinetobacter bereziniae CIP 70.12T and distantly related to any of the described species of genus Acinetobacter. Furthermore, strain LW15T could be distinguished from all known Acinetobacter species by its ability to assimilate ß-alanine and l-arginine, but not d-glucose. The principal fatty acids were C18 : 1ω9c, C16 : 0 and C16 : 1ω7c/C16 : 1ω6c. The major respiratory quinone was Q-9. Polar lipids of strain LW15T comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, four phospholipids, aminolipid and two unknown lipids. Based on its phenotypic and genotypic data, strain LW15T represents a novel species of the genus Acinetobacter, for which the name Acinetobacterpiscicola sp. nov. is proposed. The type strain is LW15T (=MCCC 1K03337T=CICC 24241T=KCTC 62134T=JCM 32101T).


Assuntos
Acinetobacter/classificação , Doenças dos Peixes/microbiologia , Peixes/microbiologia , Filogenia , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Animais , Aquicultura , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Biochim Biophys Acta ; 1859(9): 1100-1111, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26455953

RESUMO

The constitutive androstane receptor (CAR) is a key sensor in xenobiotic detoxification and endobiotic metabolism. Increasing evidence suggests that CAR also plays a role in energy metabolism by suppressing the hepatic gluconeogenesis and lipogenesis. In this study, we investigated the effects of two evodia alkaloids, rutaecarpine (Rut) and evodiamine (Evo), on gluconeogenesis and lipogenesis through their activation of the human CAR (hCAR). We found that both Rut and Evo exhibited anti-lipogenic and anti-gluconeogenic effects in the hyperlipidemic HepG2 cells. Both compounds can potently activate hCAR, and treatment of cells with hCAR antagonists reversed the anti-lipogenic and anti-gluconeogenic effects of Rut and Evo. The anti-gluconeogenic effect of Rut and Evo was due to the CAR-mediated inhibition of the recruitment of forkhead box O1 (FoxO1) and hepatocyte nuclear factor 4α (HNF4α) onto the phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) gene promoters. In vivo, we showed that treatment of mice with Rut improved glucose tolerance in a CAR-dependent manner. Our results suggest that the evodia alkaloids Rut and Evo may have a therapeutic potential for the treatment of hyperglycemia and type 2 diabetes. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie.


Assuntos
Evodia/química , Gluconeogênese/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Alcaloides Indólicos/farmacologia , Lipogênese/efeitos dos fármacos , Quinazolinas/farmacologia , Receptores Citoplasmáticos e Nucleares/genética , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Receptor Constitutivo de Androstano , Relação Dose-Resposta a Droga , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Regulação da Expressão Gênica , Gluconeogênese/genética , Glucose/metabolismo , Glucose-6-Fosfatase/genética , Glucose-6-Fosfatase/metabolismo , Células Hep G2 , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Hipoglicemiantes/isolamento & purificação , Alcaloides Indólicos/isolamento & purificação , Lipogênese/genética , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Cultura Primária de Células , Quinazolinas/isolamento & purificação , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais
10.
Small ; 13(6)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27873460

RESUMO

Antibody-drug conjugate (ADC) targeting antigens expressed on the surface of tumor cells are an effective approach for delivering drugs into the cells via antigen-mediated endocytosis. One of the well-known tumor antigens, the CD20 of B-lymphocyte, has long been suggested to be noninternalizing epitope, and is thus not considered a desirable target for ADCs. Here, sortase A (srtA)-mediated transpeptidation is used to specifically conjugate triple glycine-modified monomethyl auristatin E (MMAE), a highly toxic antimitotic agent, to anti-CD20 ofatumumab (OFA) equipped with a short C-terminal LPETG (5 amino acids) tag at heavy chain (HL), which generates ADCs that show extremely strong potency in killing CD20 positive cancer cells. One of the srtA-generated ADCs with a cleavable dipeptide linker (valine-citrulline, vc), OFA-HL-vcMMAE, shows IC50 values ranging from 5 pg mL-1 to 4.1 ng mL-1 against CD20+ lymphoma cells. Confocal laser scanning microscopy confirms that OFA-HL-vcMMAE internalization by Ramos cells is significantly improved compared to OFA alone, consistent with the high antitumor activity of the new ADC. OFA-HL-vcMMAE, at 5 mg kg-1 dose, is able to eliminate tumors with mean volume ≈400 mm3 while no obvious drug-related toxicity is observed. The results show that srtA-generated OFA-MMAE conjugate system provides a viable strategy for targeting CD20+ B lineage lymphomas.


Assuntos
Aminoaciltransferases/metabolismo , Antígenos CD20/metabolismo , Proteínas de Bactérias/metabolismo , Linhagem da Célula , Cisteína Endopeptidases/metabolismo , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Oligopeptídeos/uso terapêutico , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Biocatálise , Morte Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Endocitose/efeitos dos fármacos , Humanos , Espectrometria de Massas , Camundongos , Oligopeptídeos/síntese química , Oligopeptídeos/química , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Ultrastruct Pathol ; 40(1): 33-42, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26512751

RESUMO

This study examined the ultrastructural changes in the pulmonary mechanical barriers in a rat model of severe acute pancreatitis (SAP)-associated acute lung injury (ALI). Animals were randomized into the SAP group (n = 60) and the control group (n = 60). SAP was induced by retrograde injection of 5% taurocholic acid into the biliopancreatic duct. The morphological abnormalities assessed by histology and the lung wet/dry weight ratio and the ultrastructural abnormalities assessed by transmission electron microscope and scanning electron microscope examinations plus lanthanum nitrate tracing were compared between the two groups at 6, 12, and 24 h post-SAP induction (n = 10/group/time point). The SAP group had significantly greater extravascular effusion than the control group at each time point as assessed by the lung wet/dry weight ratio (p < .001). The severity of the tissue damage increased in the lung and pancreas over time in the SAP group (all p < .001). In the SAP group, ultrastructural damages to the endothelial, epithelial, and pleural barriers were apparent and the damages to the endothelial barrier were detected earlier than the other two barriers, suggesting its fundamental role in preventing the further development of SAP-associated ALI. Moreover, the ultrastructural abnormalities were detected earlier than symptoms and morphological changes. The ultrastructural damages in the endothelial, epithelial, and pleural barriers occurred in the early stage of SAP. The endothelial barrier is likely to be the first line to prevent the further development in this rat model of SAP-associated ALI.


Assuntos
Lesão Pulmonar Aguda/patologia , Lesão Pulmonar/patologia , Pulmão/ultraestrutura , Pancreatite/patologia , Fator de Necrose Tumoral alfa/ultraestrutura , Lesão Pulmonar Aguda/diagnóstico , Animais , Modelos Animais de Doenças , Pulmão/patologia , Masculino , Microscopia Eletrônica de Transmissão/métodos , Ratos Sprague-Dawley
12.
Drug Metab Rev ; 46(3): 362-78, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24750117

RESUMO

Reduction of C = C bonds by reductases, found in a variety of microorganisms (e.g. yeasts, bacteria, and lower fungi), animals, and plants has applications in the production of metabolites that include pharmacologically active drugs and other chemicals. Therefore, the reductase enzymes that mediate this transformation have become important therapeutic targets and biotechnological tools. These reductases are broad-spectrum, in that, they can act on isolation/conjugation C = C-bond compounds, α,ß-unsaturated carbonyl compounds, carboxylic acids, acid derivatives, and nitro compounds. In addition, several mutations in the reductase gene have been identified, some associated with diseases. Several of these reductases have been cloned and/or purified, and studies to further characterize them and determine their structure in order to identify potential industrial biocatalysts are still in progress. In this study, crucial reductases for bioreduction of C = C bonds have been reviewed with emphasis on their principal substrates and effective inhibitors, their distribution, genetic polymorphisms, and implications in human disease and treatment.


Assuntos
Carbono/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Animais , Humanos
13.
Chirality ; 26(3): 166-73, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24464553

RESUMO

Fluoxetine (FLX) is one of the most widely prescribed selective serotonin reuptake inhibitors. Although FLX is used as racemate in the clinic, the clinical pharmacokinetics of FLX and its N-demethylation metabolite norfluoxetine (NFLX) show obvious cytochrome P450 (CYP) polymorphism dependency and exhibit marked stereoselectivity. However, the kinetic profiles of CYP variants to FLX remain unclear. In the present study, some variants of human CYP2C8, CYP2C9, and CYP2D6 were first expressed in insect cells, and their catalytic roles with respect to FLX enantiomers were then investigated. CYP2C8.4 and CYP2C9.10 showed significantly lower activity and CYP2C8.3 showed significantly higher activity toward both R- and S-FLX compared with the wildtype, while CYP2C9.3, CYP2C9.13, and CYP2C9.16 showed significantly lower activity only toward R-FLX. Five CYP2C9 variants and CYP2D6.1 exhibited significantly stereoselective kinetic profiles prior to R-FLX, and CYP2C8.3 showed a slight stereoselectivity. Interestingly, obvious substrate inhibition was observed in the CYP2C9 wildtype and its three variants only in the case of R-FLX. Together, these findings suggest that CYP2C9 and CYP2D6 polymorphism may play an important role in the clearance of FLX and also in the stereoselective kinetic profiles of FLX enantiomers.


Assuntos
Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Fluoxetina/análogos & derivados , Polimorfismo Genético , Alelos , Citocromo P-450 CYP2C8 , Citocromo P-450 CYP2C9 , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Fluoxetina/química , Fluoxetina/metabolismo , Humanos , Cinética , Metilação , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Estereoisomerismo
14.
Food Chem X ; 22: 101323, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38978692

RESUMO

The presence of pesticide residues in Agrocybe aegerita has raised an extensive concern. In this paper, based on a 3-year monitoring survey, the dietary exposure risks through A. aegerita consumption for different population subgroups were assessed using both deterministic and semi-probabilistic approaches under the best-case and the worst-case scenarios. Among the 52 targeted pesticides, 28 different compounds were identified in the concentration range of 0.005-3.610 mg/kg, and 87.4 % of samples contained one or more pesticide residues. The most frequently detected pesticide was chlormequat, followed by chlorfenapyr and cyhalothrin. The overall risk assessment results indicated extremely low chronic, acute, and cumulative dietary exposure risks for consumers. Using the ranking matrix, intake risks of pesticides were ranked, revealing endsoluran, chlorpyrifos, and methamidophos to be in the high-risk group. Finally, considering various factors such as the toxicity and risk assessment outcomes of each positive pesticide, use suggestions were proposed for A. aegerita cultivation.

15.
Foods ; 13(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731680

RESUMO

Residual pesticides in Agrocybe aegerita mushroom have emerged as a significant concern and bring much uncertainty due to processing procedures. In this study, a modified QuEChERS sample preparation procedure and UPLC-MS/MS were used to analyze the residual levels of four commonly used pesticides in A. aegerita from field to product processing. The field results showed that dissipation of these targeted chemicals was consistent with the first-order kinetics, and the half-life time ranged from 20.4 h to 47.6 h. The terminal residues of the four pesticides at harvest time ranged from 9.81 to 4412.56 µg/kg in raw mushroom. The processing factors (PFs) of clothianidin, diflubenzuron, chlorbenzuron, and pyridaben ranged from 0.119 to 0.808 for the drying process and from 0.191 to 1 for the washing process. By integrating the data from the field trials, the PFs, and the consumption survey, the chronic dietary risks of the target chemicals via A. aegerita intake ranged from 2.41 × 10-5 to 5.69 × 10-2 for children and from 6.34 × 10-6 to 1.88 × 10-2 for adults, which are considerably below the threshold of 1, indicating no unacceptable risk to consumers in the Fujian province of China. This research offers foundational data for appropriate use and the maximum residue limit (MRL) establishment for these four insecticides in A. aegerita.

16.
Environ Sci Pollut Res Int ; 30(25): 67865-67879, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37119490

RESUMO

Economic growth in agriculture is often accompanied by environmental pollution. To overcome this dilemma, agricultural green total factor productivity is essential. The role of agricultural production agglomeration has been studied extensively; however, there is no apparent association between agricultural production agglomeration and agricultural green total factor productivity. We use the non-angular and non-radial super-efficiency slacks-based measure model and the global Malmquist-Luenberger productivity model to assess the agricultural green total factor productivity in 30 Chinese provinces from 2001 to 2019. In addition, we investigate the evolutionary trend, influence relationship, and internal mechanism between agricultural production agglomeration and agricultural green total factor productivity. The results show an inverted U-shaped relationship between agricultural production agglomeration and agricultural green total factor productivity. Heterogeneity analysis finds that this role is more pronounced in provinces located in the Yangtze River economic zone with strong fiscal support for agriculture and high levels of regional economic development. Regarding the mechanism analysis, enhancing green technology progress and the quality of rural human capital leads to an increase in agricultural green total factor productivity. Therefore, this study provides a new perspective on global carbon emission reduction and a theoretical and practical reference for realizing global agricultural green development.


Assuntos
Agricultura , Desenvolvimento Econômico , China , Eficiência , Tecnologia
17.
Foods ; 12(14)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37509736

RESUMO

Aflatoxin B1 (AFB1), as a class I carcinogen, poses a substantial health risk to individuals. Contamination of food sources, particularly grains and nuts, with Aspergillus flavus (A. flavus) contributes to the prevalence of AFB1. The impact of global warming has spurred research into the development of AFB1 prevention technologies. While edible fungi have shown potential in detoxifying AFB1, there is a scarcity of literature on the application of Auricularia auricular (A. auricular) in this context. This study aimed to investigate the ability and underlying mechanism of A. auricular mycelia to adsorb aflatoxin B1, as well as evaluate its protective effects on the AFB1-induced liver damage in SD rats. Additionally, the effects of temperature, time, pH, and reaction ratio on the adsorption rate were examined. Combining thermodynamic and kinetic data, the adsorption process was characterized as a complex mechanism primarily driven by chemical adsorption. In SD rats, the A. auricular mycelia exhibited alleviation of AFB1-induced liver damage. The protective effects on the liver attributed to A. auricular mycelia may involve a reduction in AFB1 adsorption in the intestine, mitigation of oxidative stress, and augmentation of second-phase detoxification enzyme activity. The adsorption method for AFB1 not only ensures safety and non-toxicity, but also represents a dietary regulation strategy for achieving effective defense against AFB1.

18.
Heliyon ; 9(8): e18850, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37593633

RESUMO

Food security constitutes a foundational cornerstone for social stability, with the achievement of sustainable agricultural production serving as a vital step towards this objective. Currently, the untimely harvesting of unripe wheat by farmers has led to a decline in food production, thereby posing a significant threat to the sustainability of China's food system and exacerbating food insecurity. Although the Chinese government has implemented various measures in response, their effectiveness has been limited. Limited scholarly literature exists on this particular issue. To advance food security in China, this study develops a tripartite evolutionary game model involving farmers, the government, and breeding enterprises. Adopting a systemic perspective, this study examines the interactions and impact mechanisms among these key actors during the wheat harvesting process. The findings indicate that the government should prioritize policies that enforce penalties. By implementing penalties within a reasonable range, the government can mitigate farmers' production costs and enhance the market price of grain. This approach discourages farmers from harvesting immature wheat and contributes to enhancing food security. Based on the research findings, this paper provides practical recommendations to guide the government in addressing food security governance issues.

19.
Front Psychol ; 14: 985889, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36998351

RESUMO

The past decade of studies showed that parenting behaviors (e.g., warmth, autonomy, and control) were associated with children's executive functions (EF) in the early years. However, different measurement methods had been used across studies, making it hard to compare the effects of parenting on EF across studies. Therefore, the present study aimed to examine the effect of the measurement methods on the relationship between maternal parenting behaviors and children's EF among a group of Chinese preschoolers. One hundred and twenty-six children (62 boys; Mage = 48.65 months) were assessed with direct measures on children's EF (inhibition and working memory tasks), and parenting behaviors of their mothers during interaction with children were observed and coded. Mothers also reported their parenting practices and children's difficulties in executive functions. The results of structural equation modeling showed that the latent performance-based EF was uniquely predicted by maternal positive control and negative control in mother-child interaction, while children's EF difficulties reported by mothers were predicted by mother-reported warmth and support, and autonomy granting. Overall, the results suggest that the relationship between maternal parenting and children's EF depends on the measurement methods of parenting and executive functions.

20.
PLoS One ; 18(11): e0294520, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38019870

RESUMO

The global cold chain logistics market is witnessing a significant upswing, driven by the rising demand for perishable food products and increasing shipment volumes worldwide. Technological advancements are leading to a more intelligent and digitally enabled cold chain logistics system. However, the high loss rate of fresh agricultural products in China poses a significant threat to the country's food security. Therefore, it is imperative to explore innovative solutions, such as blockchain, to address the challenges of traditional cold chain logistics. In this paper, inspired by the prospect theory and evolutionary game theory, we propose an evolutionary game model to analyze the behavioral strategies of the tripartite of n-level cold chain participants, consumers, and government. Using MATLAB software, the numerical simulation of the game path of this tripartite theory is conducted, and the influence of variable parameters on the evolutionary process and outcomes of the system is analyzed. The results the following: (1) The development of an effective cold chain supply chain system can be divided into three stages, and blockchain technology plays a pivotal role in creating a seamless cold chain environment. The cost of blockchain adoption, government rewards, as well as penalties can significantly influence the behavioral choices of the three stakeholders. (2) The behavior of individual cold chain participants has a strong negative externality, which can impact the behavior of others. We also find that the larger the scale of the cold chain, the lower the probability of default by the participants. (3) The government's adoption of blockchain technology and the implementation of effective incentive policies can foster the successful development of the cold chain blockchain infrastructure. Our research contributes to the theoretical understanding of cold chain logistics decision making and policy creation for the tripartite stakeholders, including cold chain participants, consumers, and government. Our findings can serve as a valuable reference for scientific decision making and policy formulation to encourage the development of a robust cold chain supply chain system.


Assuntos
Blockchain , Humanos , Teoria dos Jogos , Refrigeração , Agricultura , Tecnologia
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