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1.
Front Aging Neurosci ; 16: 1404836, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39246593

RESUMO

Background: Lacunes, a characteristic feature of cerebral small vessel disease (CSVD), are critical public health concerns, especially in the aging population. Traditional neuroimaging techniques often fall short in early lacune detection, prompting the need for more precise predictive models. Methods: In this retrospective study, 587 patients from the Neurology Department of the Affiliated Hospital of Hebei University who underwent cranial MRI were assessed. A nomogram for predicting lacune incidence was developed using LASSO regression and binary logistic regression analysis for variable selection. The nomogram's performance was quantitatively assessed using AUC-ROC, calibration plots, and decision curve analysis (DCA) in both training (n = 412) and testing (n = 175) cohorts. Results: Independent predictors identified included age, gender, history of stroke, carotid atherosclerosis, hypertension, creatinine, and homocysteine levels. The nomogram showed an AUC-ROC of 0.814 (95% CI: 0.791-0.870) for the training set and 0.805 (95% CI: 0.782-0.843) for the testing set. Calibration and DCA corroborated the model's clinical value. Conclusion: This study introduces a clinically useful nomogram, derived from binary logistic regression, that significantly enhances the prediction of lacunes in patients undergoing brain MRI for various indications, potentially advancing early diagnosis and intervention. While promising, its retrospective design and single-center context are limitations that warrant further research, including multi-center validation.

2.
Front Neurol ; 15: 1373306, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952470

RESUMO

Background: Cerebral small vessel disease (CSVD) is a common neurodegenerative condition in the elderly, closely associated with cognitive impairment. Early identification of individuals with CSVD who are at a higher risk of developing cognitive impairment is crucial for timely intervention and improving patient outcomes. Objective: The aim of this study is to construct a predictive model utilizing LASSO regression and binary logistic regression, with the objective of precisely forecasting the risk of cognitive impairment in patients with CSVD. Methods: The study utilized LASSO regression for feature selection and logistic regression for model construction in a cohort of CSVD patients. The model's validity was assessed through calibration curves and decision curve analysis (DCA). Results: A nomogram was developed to predict cognitive impairment, incorporating hypertension, CSVD burden, apolipoprotein A1 (ApoA1) levels, and age. The model exhibited high accuracy with AUC values of 0.866 and 0.852 for the training and validation sets, respectively. Calibration curves confirmed the model's reliability, and DCA highlighted its clinical utility. The model's sensitivity and specificity were 75.3 and 79.7% for the training set, and 76.9 and 74.0% for the validation set. Conclusion: This study successfully demonstrates the application of machine learning in developing a reliable predictive model for cognitive impairment in CSVD. The model's high accuracy and robust predictive capability provide a crucial tool for the early detection and intervention of cognitive impairment in patients with CSVD, potentially improving outcomes for this specific condition.

3.
Int J Mol Sci ; 25(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38791394

RESUMO

Dendrobium nobile is an important orchid plant that has been used as a traditional herb for many years. For the further pharmaceutical development of this resource, a combined transcriptome and metabolome analysis was performed in different parts of D. nobile. First, saccharides, organic acids, amino acids and their derivatives, and alkaloids were the main substances identified in D. nobile. Amino acids and their derivatives and flavonoids accumulated strongly in flowers; saccharides and phenols accumulated strongly in flowers and fruits; alkaloids accumulated strongly in leaves and flowers; and a nucleotide and its derivatives and organic acids accumulated strongly in leaves, flowers, and fruits. Simultaneously, genes for lipid metabolism, terpenoid biosynthesis, and alkaloid biosynthesis were highly expressed in the flowers; genes for phenylpropanoids biosynthesis and flavonoid biosynthesis were highly expressed in the roots; and genes for other metabolisms were highly expressed in the leaves. Furthermore, different members of metabolic enzyme families like cytochrome P450 and 4-coumarate-coA ligase showed differential effects on tissue-specific metabolic accumulation. Members of transcription factor families like AP2-EREBP, bHLH, NAC, MADS, and MYB participated widely in differential accumulation. ATP-binding cassette transporters and some other transporters also showed positive effects on tissue-specific metabolic accumulation. These results systematically elucidated the molecular mechanism of differential accumulation in different parts of D. nobile and enriched the library of specialized metabolic products and promising candidate genes.


Assuntos
Dendrobium , Regulação da Expressão Gênica de Plantas , Transcriptoma , Dendrobium/genética , Dendrobium/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica/métodos , Metaboloma , Flores/genética , Flores/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Frutas/metabolismo , Frutas/genética , Flavonoides/metabolismo , Flavonoides/biossíntese , Alcaloides/metabolismo
4.
J Colloid Interface Sci ; 670: 395-408, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38772256

RESUMO

Photothermal synergistic catalysis is a novel technology that converts energy. In this study, ZnIn2S4 with S-vacancy (ZIS-Vs) is combined with Nickel, Nickle Oxide and Carbon Nanofiber aggregates (Ni-NiO@CNFs) to create a multi-interface coupled photocatalyst with double Schottky barrier, double channel and mixed photothermal conversion effect. Theoretical calculation confirms that the Gibbs free energy (ΔG*H) of the S-scheme heterojunction in the composite material is -0.07 eV, which is close to 0. This promotes the adsorption of H* and accelerates the formation of H2. Internal photothermal catalysis is achieved by visible-near infrared (Vis-NIR, RT) irradiation. The internal photothermal catalytic hydrogen production rate of the best sample (0.9Ni-NiO@CNFs/ZIS-Vs) is as high as 17.24 mmol·g-1·h-1, and its photothermal conversion efficiency (η) is as high as 61.42 %. Its hydrogen production efficiency is 20.52 times that of ZIS-Vs (0.84 mmol·g-1·h-1) under visible light (Vis, RT) conditions. When the Vis-NIR light source is combined with external heating (75 ℃), the hydrogen production efficiency is further improved, and the hydrogen production efficiency (29.16 mmol·g-1·h-1) is 26.75 times that of ZIS-Vs (1.09 mmol·g-1·h-1, Vis-NIR, RT). Further analysis shows that the increase in hydrogen production resulted from the apparent activation energy (Ea) of the catalyst decreasing from 16.7 kJ·mol-1 to 9.28 kJ·mol-1. This study provides a valuable prototype for the design of an efficient photothermal synergistic catalytic system.

5.
Mar Drugs ; 22(3)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38535479

RESUMO

Phycoerythrin and polysaccharides have significant commercial value in medicine, cosmetics, and food industries due to their excellent bioactive functions. To maximize the production of biomass, phycoerythrin, and polysaccharides in Porphyridium purpureum, culture media were supplemented with calcium gluconate (CG), magnesium gluconate (MG) and polypeptides (BT), and their optimal amounts were determined using the response surface methodology (RSM) based on three single-factor experiments. The optimal concentrations of CG, MG, and BT were determined to be 4, 12, and 2 g L-1, respectively. The RSM-based models indicated that biomass and phycoerythrin production were significantly affected only by MG and BT, respectively. However, polysaccharide production was significantly affected by the interactions between CG and BT and those between MG and BT, with no significant effect from BT alone. Using the optimized culture conditions, the maximum biomass (5.97 g L-1), phycoerythrin (102.95 mg L-1), and polysaccharide (1.42 g L-1) concentrations met and even surpassed the model-predicted maximums. After optimization, biomass, phycoerythrin, and polysaccharides concentrations increased by 132.3%, 27.97%, and 136.67%, respectively, compared to the control. Overall, this study establishes a strong foundation for the highly efficient production of phycoerythrin and polysaccharides using P. purpureum.


Assuntos
Gluconatos , Porphyridium , Ficoeritrina , Gluconato de Cálcio , Polissacarídeos
6.
Bioresour Technol ; 397: 130474, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395234

RESUMO

This work aims at intensifying the simultaneous removal of nitrogen and phosphorus of an integrated aerobic granular sludge (AGS) - membrane bioreactor (MBR) by Acinetobacter junii. After acclimation and enrichment in a sequencing batch reactor (SBR), Acinetobacter junii, a kind of denitrifying phosphate accumulating organism (DPAO), was successfully screened in the used SBR. Then it was verified to be capable of effectively enhancing the performance in the simultaneous removal of nitrogen and phosphorus of AGS-MBR. In the system, DPAO (Acinetobacter junii) mainly occurred in AGS, and the highest ratio even reached 22.8%, but its competitive advantages highly depend on the size of AGS. The presented results can cultivate AGS and enrich DPAO simultaneously to improve the removal of nitrogen and phosphorus of an AGS-MBR, which provide an environmentally friendly approach to upgrade traditional wastewater treatment processes.


Assuntos
Acinetobacter , Fósforo , Esgotos , Nitrogênio , Fosfatos , Reatores Biológicos , Eliminação de Resíduos Líquidos
7.
Opt Express ; 32(1): 313-324, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175058

RESUMO

Magnetic-free nonreciprocal optical devices have attracted great attention in recent years. Here, we investigated the magnetic-free polarization rotation of light in an atom vapor cell. Two mechanisms of magnetic-free nonreciprocity have been realized in ensembles of hot atoms, including electromagnetically induced transparency and optically-induced magnetization. For a linearly polarized input probe light, a rotation angle up to 86.4° has been realized with external control and pump laser powers of 10 mW and is mainly attributed to the optically-induced magnetization effect. Our demonstration offers a new approach to realize nonreciprocal devices, which can be applied to solid-state atom ensembles and may be useful in photonic integrated circuits.

8.
Enzyme Microb Technol ; 173: 110368, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043249

RESUMO

Most of the dsDNA cyanophages employ holin-endolysin lysis systems to damage the host cells. This study aimed to elucidate the lytic activity of ORF91 and ORF117 in the cyanophage MaMV-DH01, which lacked a conventional cholinesterase system. These two proteins contained Lyz-like superfamily domains and were annotated as a member of GH family 19 (named DHGH19) and peptidase (named DHpeptidase), respectively. Overexpression of DHGH19 in E. coli over a 5 h course demonstrated potent bactericidal activity, evident from significant growth inhibition, membrane damage, and leakage of intracellular enzymes of E. coli cells. However, the lytic activity of DHpeptidase was relatively weaker, exhibiting a bacteriostatic effect. It was important to highlight that the specific mutation of enzyme-catalyzed residues in DHGH19 (E122 and E131) showed that these were the essential amino acids for DHGH19 to exert its bactericidal activity. Furthermore, the lytic function of DHGH19 and DHpeptidase on cyanobacteria cells was confirmed by their overexpression in the cyanobacterium Synechocystis sp. PCC6803. Overall, this study provides novel insights into the lytic mechanism of Myoviridae cyanophage, offering potential alternatives for the development of GH19 and peptidase as new antibacterial agents in the future.


Assuntos
Bacteriófagos , Cianobactérias , Peptídeo Hidrolases , Myoviridae/metabolismo , Muramidase , Escherichia coli/genética , Escherichia coli/metabolismo , Endopeptidases/genética , Endopeptidases/metabolismo , Cianobactérias/metabolismo , Bacteriófagos/genética
9.
Appl Opt ; 62(26): 7058-7066, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707047

RESUMO

A photodetector signal-to-noise ratio (SNR) over 1000 is one of the prerequisites to realizing the correlated photon radiometric benchmark with a relative standard uncertainty of 0.3% (k=1). To improve the SNR for low-photon flux detection, a switched integration amplifier (SIA) is designed to achieve a noise equivalent current of a fA level. A wide spectrum and low-photon flux measurement facility are built to evaluate the SNR at a photon rate of 108 s -1 within the spectral range of 350-1000 nm. SNRs of the SIA-based Si photodetector are shown to be greater than 1000 at representative wavelengths.

10.
Fish Shellfish Immunol ; 142: 109080, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37748586

RESUMO

NK-lysins are one of the most abundant antimicrobial peptides produced by cytotoxic T lymphocytes (CTLs) and natural killer cells (NKs), and identified as a new class of intrinsically disordered proteins, playing critical roles in the cell-mediated cytotoxicity response, as well as immunomodulatory and antimicrobial activities upon a significant range of pathogens. In the present study, an NK-lysin was identified from Obscure puffer Takifugu obscurus (ToNK-lysin). The open reading frame of ToNK-lysin sequence spans 423 bp, encoding a peptide with 140 amino acids which shares a moderate residue identity (18%-60%) with NK-lysin of mammals and other teleost species. Phylogenetic analysis revealed that ToNK-lysin was most closely related to NK-lysins from the Pleuronectiformes (Bastard halibut Paralichthys olivaceus and Pacific halibut Hippoglossus stenolepis). Comprehensive computational analysis revealed that ToNK-lysin have substantial level of intrinsic disorder, which might be contribute to its multifunction. The transcripts of the ToNK-lysin were detected in multiple examined tissues and most abundant in gills. After bacterial and Poly I:C challenge, the transcriptional levels of ToNK-lysin were significantly up-regulated in the head kidney, liver and spleen at different time points. The recombinant ToNK-lysin showed significant antibacterial activity against Vibrio harveyi and Escherichia coli, and the ToNK-lysin treatment not only reduced the bacterial loads in liver and head kidney, but also alleviated the pathogen-mediated upregulation of immune-related genes. In addition, the co-incubation with rToNK-lysin protein remarkably degraded bacterial genomic DNA, suggesting the potential mechanism of ToNK-lysin against microbes. These results suggest that ToNK-lysin possess antibacterial and immunoregulatory function both in vivo and in vitro, which may allow it a potential applicability to the aquaculture industry.


Assuntos
Antibacterianos , Tetraodontiformes , Animais , Sequência de Aminoácidos , Filogenia , Antibacterianos/farmacologia , Adjuvantes Imunológicos , Fatores Imunológicos/farmacologia , Proteolipídeos/genética , Mamíferos/metabolismo
11.
Metabolites ; 13(6)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37367860

RESUMO

The medicinal plant Dendrobium nobile is an important natural antioxidant resource. To reveal the antioxidants of D. nobile, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was employed for metabolic analysis. The H2O2-induced oxidative damage was used in human embryonic kidney 293T (H293T) cells to assess intracellular antioxidant activities. Cells incubated with flower and fruit extracts showed better cell survival, lower levels of reactive oxygen species (ROS), and higher catalase and superoxide dismutase activities than those incubated with root, stem, and leaf extracts (p < 0.01). A total of 13 compounds were newly identified as intracellular antioxidants by association analysis, including coniferin, galactinol, trehalose, beta-D-lactose, trigonelline, nicotinamide-N-oxide, shikimic acid, 5'-deoxy-5'-(methylthio)adenosine, salicylic acid, isorhamnetin-3-O-neohespeidoside, methylhesperidin, 4-hydroxybenzoic acid, and cis-aconitic acid (R2 > 0.8, Log2FC > 1, distribution > 0.1%, and p < 0.01). They showed lower molecular weight and higher polarity, compared to previously identified in vitro antioxidants in D. nobile (p < 0.01). The credibility of HPLC-MS/MS relative quantification was verified by common methods. In conclusion, some saccharides and phenols with low molecular weight and high polarity helped protect H293T cells from oxidative damage by increasing the activities of intracellular antioxidant enzymes and reducing intracellular ROS levels. The results enriched the database of safe and effective intracellular antioxidants in medicinal plants.

12.
Microbiol Res ; 272: 127384, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37141852

RESUMO

In this study, a strain of Clostridium butyricum was isolated from the intestine of Litopenaeus vannamei with the method of anaerobic microbial isolation and culture. Next, the probiotic properties of LV1 were evaluated with susceptibility tests, tolerance tests, and whole genome sequencing in vivo and in vitro, followed by the analysis of the effect of LV1 on the growth performance, immune response, and disease resistance of Litopenaeus vannamei. According to the results, the 16 S rDNA sequence of LV1 was 100% homolofgous to the reference sequence of Clostridium butyricum. Moreover, LV1 was resistant to several antibiotics including amikacin, streptomycin, and gentamicin and highly tolerated artificial gastric and artificial intestinal fluids. The whole genome of LV1 was 4625,068 bp in size and included 4336 coding genes. Among these genes, GO, KEGG, and COG databases exhibited the highest number of genes annotated to metabolic pathway classes and 105 genes annotated as glycoside hydrolases. Meanwhile, 176 virulence genes were predicted. The use of diets supplemented with 1.2 × 109 CFU/kg of LV1 live cells significantly increased the weight gain and specific growth rates of Litopenaeus vannamei and the activity of serum superoxide dismutase, glutathione peroxidase, acid phosphatase, and alkaline phosphatase (P < 0.05). Meanwhile, the use of these diets markedly improved the relative expression of intestinal immunity- and growth-related genes. In conclusion, LV1 has excellent probiotic properties. Specifically, the addition of 1.2 × 109 CFU/kg of LV1 live cells to the diet improved the growth performance, immune response, and disease-resistance of Litopenaeus vannamei.


Assuntos
Clostridium butyricum , Resistência à Doença , Humanos , Resistência à Doença/genética , Clostridium butyricum/genética , Suplementos Nutricionais/análise , Dieta , Sequenciamento Completo do Genoma , Ração Animal/análise , Imunidade Inata
13.
Artigo em Inglês | MEDLINE | ID: mdl-37040428

RESUMO

A novel rod-shaped, Gram-stain-positive, spore-forming and motile by peritrichous flagella strain, designated HJL G12T, was isolated from the root of Chinese herb Dendrobium nobile. Strain HJL G12T grew optimally at pH 7.0, 30 °C and in the presence of 1.0 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene and genomic sequences showed that HJL G12T clustered with Paenibacillus chibensis NBRC 15958T and Paenibacillus dokdonensis YH-JAE5T with 98.3 and 98.2 % sequence similarity. The DNA-DNA hybridization values between strain HJL G12T and the two reference strains were 23.6 % and 24.9 %, respectively. Menaquinone-7 was the only respiratory quinone and meso-diaminopimelic acid was present in the cell-wall peptidoglycan. Antesio-C15 : 0 and iso-C16 : 0 were detected to be the major cellular fatty acids. The cellular polar lipid profile contained diphosphatidyglycerol, phosphatidylglycerol, phosphatidylethanolamine, lysyl-phospatidylglycerol and three unidentified aminophospholipids. Based on these results, strain HJL G12T is considered to represent a novel species within the genus Paenibacillus, for which the name Paenibacillus dendrobii sp. nov. is proposed, with HJL G12T (=NBRC 115617T=CGMCC 1.18520T) as the type strain.


Assuntos
Dendrobium , Paenibacillus , Ácidos Graxos/química , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Composição de Bases , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana
14.
J Appl Biomed ; 21(1): 23-35, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36708715

RESUMO

Increasing data has confirmed the potential anticancer properties of Dendrobium, a traditional Chinese herb. However, most anticancer compositions from the plant of Dendrobium were usually extracted by high polar solvent, while weak polar compositions with excellent anticancer activity remained largely unexplored. In this study, the differences between ether extract and ethanol extract of Dendrobium nobile Lindl. on chemical components and anticancer activities were investigated, as well as the anticancer mechanisms among different extracts. The results demonstrated that the ether extract exhibited a stronger anticancer effect than ethanol extract, and its anticancer effect was mainly due to weak polar compounds rather than polysaccharides and alkaloids. Quantitative proteomics suggested that the ether extract significantly stimulated the over-expression of immature proteins, the endoplasmic reticulum stress and unfolded protein response were subsequently induced, the intracellular reactive oxygen species level was seriously elevated, and oxidative stress occurred in the meanwhile. Eventually, autophagy and apoptosis were activated to cause cell death. Our findings demonstrate that the ether extract of D. nobile is a potential candidate for anticancer drug development, and that future research on anticancer drugs derived from medicinal plants should also concentrate on weak polar compounds.


Assuntos
Antineoplásicos , Dendrobium , Éter , Dendrobium/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Autofagia , Biossíntese de Proteínas , Antineoplásicos/farmacologia , Etanol
15.
Int J Anal Chem ; 2022: 9510598, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36032803

RESUMO

Dendrobium nobile is a beautiful orchid and a widely used medicinal plant. In vitro antioxidant assays suggested that D. noblie flower extracts showed significantly higher 2, 2'-azinobis-3-ethylbenzthiazoline-6-sulfonate (ABTS) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging rates and much more ferric-reducing power than those of root, stem, leaf and fruit. To better understand the antioxidant basis of D. nobile flower, high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was used for metabolic identification and quantification. Finally, there were 72 metabolites among the total of 712 identified components showed significant association (coefficient >0.8, p < 0.05) with ABTS scavenging rates, DPPH scavenging rates, and ferric-reducing power. The three enriched classes of flower metabolites, including amino acids and their derivatives, organic acids and their derivatives, and flavonoids, formed the main antioxidant basis. The significantly accumulated rutin, astragalin, isomucronulatol-7-O-glucoside, quercetin 4'-O-glucoside, methylquercetin O-hexoside, caffeic acid, caffeic acid O-glucoside, and p-coumaric acid (Log2(fold change) >2, p < 0.01, distribution in flower >0.1%) made a key contribution to the higher antioxidant activities in flower. The relative quantification results of HPLC-MS/MS were verified by the common quantification methods. The antioxidant basis revealed of D. nobile flower will be helpful in the production of healthy or beauty products.

16.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3330-3336, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34396752

RESUMO

The present study aimed to explore the correlation between agronomic traits and quality indexes of Dendrobium nobile and its application value in agricultural breeding. The cultivated strains of D. nobile in Hejiang-Chishui producing areas were extensively collected,and the main agronomic traits and quality indexes were measured. The agronomic traits with significant correlation with quality indexes were screened out by the correlation analysis,and then the parental lines and self-bred F_1 generation plants were furtherverified. Among 96 lines of D. nobile,the content of soluble polysaccharides showed a significant negative correlation with dendrobine( P < 0. 01),and no significant correlation with agronomic traits in stems and leaves. The content of dendrobine exhibited a significant positive correlation with the stem width-thickness ratio( at the largest cross section; P < 0. 01),and no significant correlation with other agronomic traits. Regression analysis further verified the positive correlation between dendrobine content and stem width-thickness ratio( R2> 0. 9). Two lines,JC-10 and JC-35,with significant differences in stem width-thickness ratio were screened out( P <0. 05). The corresponding F1 generation plants by self-pollination both showed that the dendrobine content was higher with greater stem width-thickness ratio( P < 0. 01). The experimental results suggested that within a certain range,the dendrobine content was higher in D. nobile with flatter stem. Therefore,in the breeding of D. nobile,this specific trait could be used for screening plants with high content of quality indexes such as dendrobine.


Assuntos
Dendrobium , Agricultura , Dendrobium/genética , Melhoramento Vegetal , Folhas de Planta/genética , Polissacarídeos
17.
Chemosphere ; 279: 130537, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33862361

RESUMO

The superoxide anion radical (O2•-) is an important reactive oxygen species (ROS), and participates in several chemical reactions and biological processes. In this report, O2•- was produced by irradiating riboflavin in an O2-saturated solution by ultraviolet light with a maximum emission at 365 nm. And the contribution of O2•- to 2, 4, 6-trichlorophenol (2, 4, 6-TCP) was investigated by a combination of laser flash photolysis (LFP) and UV light steady irradiation technique. The results of steady-state experiments showed that the photochemical decomposition efficiency of 2, 4, 6-TCP decreased with the increase of the initial concentration of TCP, while the increase of pH and riboflavin concentration promoted the photochemical reaction. The second-order rate constant of the reaction of the superoxide anion radical with 2, 4, 6-TCP phenoxyl radical (TCP•) was (9.9 ± 0.9) × 109 L mol-1 s-1 determined by laser flash photolysis techniques. The dechlorination efficiency was 61.5% after illuminating the mixed solution with UV light for 2 h. The conversion of 2, 4, 6-trichlorophenol was accompanied by the reductive dechlorination process induced by superoxide ions. The main steady products of the photochemical reaction of 2, 4, 6-TCP with O2•- were 2, 6-dichlorophenol (DCP), 2, 6-dichloro-1, 4-benzoquinone (DCQ) and 2, 6-dichlorohydroquinone (DCHQ). The addition process was the preferred process in the total reaction of superoxide ions with 2, 4, 6-TCP phenoxyl radical. These results indicated that the reaction of 2, 4, 6-TCP with O2•- was a potential conversion pathway and contribute to atmospheric aqueous phase chemistry.


Assuntos
Clorofenóis , Superóxidos , Cinética , Fotólise , Raios Ultravioleta , Água
18.
NanoImpact ; 21: 100280, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-35559772

RESUMO

Copper nanoparticles (CuNPs), a new pollutant in water environments, were widely used in various industrial and commercial applications. This study indicated that the presence of CuNPs exposure under environmental related concentration is an inducing factor that contributes to the fatty liver formation in Takifugu fasciatus. Furthermore, we explored the fatty liver formation mechanism. The results shown, (1) the cloned genes related to endoplasmic reticulum stress (ERS) (GRP78, IRE-1α, PERK, and ATF-6α) were highly expressed in the liver of T. fasciatus. (2) after 30-days exposure, CuNPs accumulated in the endoplasmic reticulum of liver and induced the appearance of ERS, then activated unfolded protein response (UPR) signaling pathway. Furthermore, the SREBP-1c pathway that plays a key role in lipid synthesis was activated. (3) by using 4-PBA and GSK inhibitors to respectively stimulate ERS and PKR-like ER kinase (PERK) through in vitro experiments, we confirmed that CuNPs induced the fatty liver formation in T. fasciatus triggered by the PERK-EIF2α pathway by activating the SREBP-1c pathway to promote fatty liver formation. This study provides a new perspective for identifying the pathogens of fatty liver formation, and adds to the knowledge of the ecological safety data service of CuNPs in water.


Assuntos
Fígado Gorduroso , Nanopartículas , Animais , Cobre/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Fígado Gorduroso/induzido quimicamente , Nanopartículas/efeitos adversos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Takifugu/metabolismo , Água
19.
J Food Biochem ; 44(12): e13509, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33025642

RESUMO

Dendrobium liquor obtained by soaking Dendrobium in Chinese liquor is considered as a health drink in China. Here, we found the pretreatment of extract of Dendrobium nobile Lindl. liquor (DNLE) attenuated the oxidative damage to cells caused by H2 O2 , while the abilities of DNLE of eliminating extracellular free radicals and promoting the activities of intracellular antioxidant enzymes were observed. Quantitative proteomics identified 375 differentially expressed proteins caused by H2 O2 treatment in 293T cells. However, only 12 differentially expressed proteins were found in DNLE-pretreated cells which under the same oxidative damage. This suggested that the pretreatment of DNLE could suppress the disorder of protein expressions caused by oxidative stress which could induce cell death. Besides, DNLE was helpful for avoiding the unfolded protein response (UPR) and cell cycle disorder caused by oxidative stress. Taken together, these results demonstrated that Dendrobium liquor could be a healthy herbal drink with antioxidant function. PRACTICAL APPLICATIONS: Dendrobium is used as an edible herb and a tonic food in traditional Chinese medicine. Dendrobium liquor obtained by soaking Dendrobium with Chinese liquor is also regarded as a nourishing health drink. However, there is rare research data on biological activity of Dendrobium liquor. Our current results demonstrated that the extract of Dendrobium nobile Lindl. liquor (DNLE) possessed the ability of eliminating free radicals in/out the human cells. More importantly, DNLE could help cells to resist the interference on cell life activities caused by oxidative stress. Since many evidences suggested that oxidative stress is linked to human disease and aging, and chemical antioxidant has some side effects on health, Dendrobium liquor can serve as a natural health drink with antioxidant function. Furthermore, the active ingredients in DNLE also possess the potential to be developed as natural antioxidant additive in food and cosmetics.


Assuntos
Dendrobium , China , Radicais Livres , Humanos , Oxidantes , Proteômica
20.
J Int Med Res ; 48(6): 300060520926020, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32567449

RESUMO

OBJECTIVE: To evaluate the association between dyslipidaemia and Alzheimer's disease (AD) in a cohort of postmenopausal women. METHODS: This retrospective study analysed data from postmenopausal women with early AD (group AD) and a cohort of healthy age- and sex-matched control subjects (group NC) that were considered to be within standard limits according to a neuropsychological assessment between March 2010 and March 2019. The primary endpoints were body mass index and lipid-related laboratory parameters, including leptin, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol, adiponectin, triglycerides, apolipoprotein A1, apolipoprotein B and apolipoprotein E4, which were evaluated using multivariate binary logistic analysis. RESULTS: The study enrolled 200 postmenopausal women with early AD (mean ± SD age 69.34 ± 6.25 years) and 180 control subjects (mean ± SD age 67.48 ± 7.42 years). Lower HDL-C and higher LDL-C were risk factors for AD. A multivariate binary logistic regression model demonstrated that lower HDL-C and higher LDL-C were the only variables associated with the development of AD (odds ratio [OR] 21.14, 95% confidence interval [CI] 2.47, 4.13; OR 36.35, 95% CI 1.24, 3.38; respectively). CONCLUSION: Both low HDL-C and high LDL-C were associated with the occurrence of AD in a cohort of postmenopausal women.


Assuntos
Doença de Alzheimer/complicações , Dislipidemias/epidemiologia , Lipoproteínas/análise , Idoso , Doença de Alzheimer/epidemiologia , Apolipoproteína A-I/análise , Apolipoproteína A-I/metabolismo , Apolipoproteínas B/análise , Índice de Massa Corporal , China/epidemiologia , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Estudos de Coortes , Dislipidemias/metabolismo , Feminino , Humanos , Lipídeos/análise , Lipoproteínas/metabolismo , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Pós-Menopausa/fisiologia , Estudos Retrospectivos , Fatores de Risco , Triglicerídeos/análise
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