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1.
Huan Jing Ke Xue ; 45(8): 4812-4824, 2024 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-39168698

RESUMO

The contents of eight heavy metals (Cr, Ni, Cu, Zn, Cd, Pb, As, and Hg) were determined based on the surface soil samples of sewage irrigation and industrial complex in Kaifeng City. The absolute factor analysis-multiple linear regression (APCS-MLR) model and positive matrix factorization (PMF) model were used to analyze the sources and contribution rates of heavy metals in soil combined with correlation analysis and systematic cluster analysis. The results showed that: ① The average values of ω(Cr), ω(Ni), ω(Cu), ω(Zn), ω(Cd), ω(Pb), ω(As), and ω(Hg) in the study area were 52.19, 25.00, 42.03, 323.53, 1.79, 53.45, 9.43, and 0.20 mg·kg-1, respectively, and Cr, Ni, and As are lower than the background values of tidal soil. Cu, Zn, Cd, Pb, and Hg are higher than the background values of the tidal soil. ② There were four sources of the eight heavy metals: natural sources, agricultural sewage irrigation sources, industrial atmospheric sedimentation sources, and transportation sources. Cr and Ni were mainly from natural sources; Cu, Zn, Cd, and Pb were mainly from agricultural sewage irrigation and transportation sources; As was mainly from natural sources and agricultural sewage irrigation; and Hg was mainly from industrial atmospheric sedimentation. ③ The APCS-MLR and PMF source analysis results indicated that industrial and agricultural activities were the main sources of heavy metals in the soil of the study area. The average contribution rates of APCS-MLR in the nine sampling areas of the research area were 76.01% (natural sources and agricultural sewage irrigation sources), 22.71% (industrial atmospheric sedimentation sources and transportation sources), and 1.28% (unknown sources). The average contribution rates of PMF were 59.66% (natural sources and agricultural sewage irrigation sources) and 40.34% (industrial atmospheric sedimentation sources and transportation sources). The source analysis results of the LZ, XZ, NLT, PT, YLZ, and BC models were basically consistent, and WL was better in the APCS-MLR model, whereas SG and QT were better in the PMF model. The research results can provide a scientific basis for the prevention and control of soil heavy metal pollution and environmental remediation.

2.
Int J Biol Macromol ; 276(Pt 1): 133025, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38852737

RESUMO

The Rosa cymosa Tratt, an herbal plant from the Rosaceae family, has historically been valued in China for its medicinal and edible properties. In this study, a novel polysaccharide from R. cymosa fruit, termed PRCP (purified R. cymosa polysaccharide), was isolated using water extraction, decolorization, deproteinization, and ion-exchange chromatography. The structural characteristics of PRCP were investigated using monosaccharide composition analysis, methylation, GPC, FTIR, CD, and NMR spectroscopy. The immunomodulatory effect and potential mechanism of PRCP were evaluated in vitro using a macrophage cell model. Results indicated that PRCP (37.28 kDa) is a highly branched polysaccharide (72.61 %) primarily composed of arabinogalactan, rhamnogalacturonan, and galactoglucan domains with 13 types of glycosidic linkage fragments. Furthermore, PRCP appears to modulate immunomodulatory effects by influencing the phosphorylation of P38 and JNK proteins in the MAPK pathway. Collectively, these findings highlight the potential of PRCP as a promising natural functional food ingredient for immunostimulation.


Assuntos
Frutas , Sistema de Sinalização das MAP Quinases , Polissacarídeos , Rosa , Rosa/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Camundongos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Frutas/química , Animais , Células RAW 264.7 , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Monossacarídeos/análise , Fosforilação/efeitos dos fármacos
3.
J Ethnopharmacol ; 327: 118049, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38484954

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Liriope spicata Lour., a species listed in the catalogue of 'Medicinal and Edible Homologous Species', is traditionally used for the treatment of fatigue, restlessness, insomnia and constipation. AIM OF THE STUDY: This study is aimed to evaluate the sedative and hypnotic effect of the saponins from a natural plant L. spicata Lour. in vivo. MATERIALS AND METHODS: The total saponin (LSTS) and purified saponin (LSPS) were extracted from L. spicata, followed by a thorough analysis of their major components using the HPLC-MS. Subsequently, the therapeutic efficacy of LSTS and LSPS was evaluated by the improvement of anxiety and depression behaviors of the PCPA-induced mice. RESULTS: LSTS and LSPS exhibited similar saponin compositions but differ in their composition ratios, with liriopesides-type saponins accounting for a larger proportion in LSTS. Studies demonstrated that both LSTS and LSPS can extend sleep duration and immobility time, while reducing sleep latency in PCPA-induced mice. However, there was no significant difference in weight change among the various mice groups. Elisa results indicated that the LSTS and LSPS could decrease levels of NE, DA, IL-6, and elevate the levels of 5-HT, NO, PGD2 and TNF-α in mice plasma. LSTS enhanced the expression of neurotransmitter receptors, while LSPS exhibited a more pronounced effect in regulating the expression of inflammatory factors. In conclusion, the saponins derived from L. spicata might hold promise as ingredients for developing health foods with sedative and hypnotic effects, potentially related to the modulation of serotonergic and GABAAergic neuron expression, as well as immunomodulatory process.


Assuntos
Saponinas , Distúrbios do Início e da Manutenção do Sono , Animais , Camundongos , Hipnóticos e Sedativos/farmacologia , Hipnóticos e Sedativos/uso terapêutico , Distúrbios do Início e da Manutenção do Sono/induzido quimicamente , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Saponinas/farmacologia , Saponinas/uso terapêutico , Plantas Comestíveis , Ansiedade
4.
Plant Cell Rep ; 43(1): 5, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38127154

RESUMO

KEY MESSAGE: The content of flavonoids could increase in A. canescens under saline conditions. Overexpression of AcCHI in transgenic A. thaliana promotes flavonoid biosynthesis, thereby functioning in the tolerance of transgenic plants to salt and osmotic stress by maintaining ROS homeostasis. Atriplex canescens is a halophytic forage shrub with excellent adaptation to saline environment. Our previous study showed that a large number of genes related to the biosynthesis of flavonoids in A. canescens were significantly up-regulated by NaCl treatments. However, it remains unclear whether flavonoids are involved in A. canescens response to salinity. In this study, we found that the accumulation of flavonoids significantly increased in either the leaves or roots of A. canescens seedling under 100 and 300 mM NaCl treatments. Correspondingly, AcCHS, AcCHI and AcF3H, which encode three key enzymes (chalcone synthases (CHS), chalcone isomerase (CHI), and flavanone 3-hydroxylase (F3H), respectively) of flavonoids biosynthesis, were significantly induced in the roots or leaves of A. canescens by 100 or 300 mM NaCl. Then, we generated the transgenic Arabidopsis thaliana overexpressing AcCHI and found that transgenic plants accumulated more flavonoids through enhancing the pathway of flavonoids biosynthesis. Furthermore, overexpression of AcCHI conferred salt and osmotic stress tolerance in transgenic A. thaliana. Contrasted with wild-type A. thaliana, transgenic lines grew better with greater biomass, less H2O2 content as well as lower relative plasma permeability in either salt or osmotic stress conditions. In conclusion, our results indicate that flavonoids play an important role in A. canescens response to salt stress through reactive oxygen species (ROS) scavenging and the key enzyme gene AcCHI in flavonoids biosynthesis pathway of A. canescens has the potential to improve the stress tolerance of forages and crops.


Assuntos
Arabidopsis , Atriplex , Plantas Tolerantes a Sal/genética , Tolerância ao Sal/genética , Atriplex/genética , Espécies Reativas de Oxigênio , Arabidopsis/genética , Peróxido de Hidrogênio , Cloreto de Sódio/farmacologia , Plantas Geneticamente Modificadas , Flavonoides
5.
Sci Rep ; 13(1): 10625, 2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37391585

RESUMO

Forest musk deer (Moschus berezovskii) are currently a threatened species under conservation, and the development of captive populations is restricted by health problems. To evaluate the application potential of interferon (IFN)-ω in the prevention and control of forest musk deer disease, 5 forest musk deer IFN-ω (fmdIFNω) gene sequences were successfully obtained by homologous cloning method for the first time. FmdIFNω5 was selected and recombinant fmdIFNω protein (rIFNω) was successfully expressed by pGEX-6P-1 plasmid and E. coli expression system. The obtained protein was used to stimulate forest musk deer lung fibroblasts cells FMD-C1 to determine its regulatory effect on interferon-stimulated genes (ISGs). In addition, an indirect ELISA method based on anti-rIFNω serum was established to detect endogenous IFN-ω levels in 8 forest musk deer. The results showed that there were 18 amino acid differences among the 5 fmdIFNω subtypes, all of which had the basic structure to exert the activity of type I IFN and were close to Cervus elaphus IFN-ω in the phylogenetic tree. The protein expressed was 48 kDa, and the transcription levels of all ISGs were increased in FMD-C1 cells stimulated by rIFNω, and the amount of transcription accumulation was time-dependent. Meanwhile, Anti-rIFNω serum of mice could react with both rIFNω and forest musk deer serum, and the OD450nm value of forest musk deer serum with the most obvious symptoms was the highest, suggesting that the level of natural IFN-ω in different forest musk deer could be monitored by the rIFNω-based ELISA method. These results indicate that fmdIFNω has the potential as an antiviral drug and an early indication of innate immunity, which is of great significance for the prevention and control of forest musk deer diseases.


Assuntos
Cervos , Interferon Tipo I , Animais , Camundongos , Escherichia coli/genética , Filogenia , Clonagem Molecular , Ruminantes , Interferon Tipo I/genética , Florestas
6.
Mol Nutr Food Res ; 67(12): e2200364, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36934422

RESUMO

SCOPE: Dried Ziziphus jujuba Mill. kernel is a potential natural source of nutraceutical and therapeutic agents in China. Recent researches have shown that the saponins of dried Z. jujuba Mill. kernel (SZJs: SZJ-1 and SZJ-2) have various biological effects. However, the hypoglycemic activities and underlying mechanisms of SZJs remain obscure. METHOD AND RESULTS: In the current study, two saponins SZJ-1 and SZJ-2 mainly composed of betulinic acid, spinosin, jujuboside A, and jujuboside B are extracted and is olated from dried Z. jujuba Mill. kernel. The SZJ-1 and SZJ-2 could significantly inhibit the activities of digestion enzymes α-glucosidase and α-amylases. The hypoglycemic ability of SZJ-1 and SZJ-2 is further investigated and the results show that SZJ-1 and SZJ-2 can improve the hyperglycemic by increasing the glucose consumption, improving the superoxide dismutase (SOD), hexokinase (HK), pyruvate kinase (PK) activities, and decrease the MDA content of insulin resistant HepG2 cells. Furthermore, SZJ-1 and SZJ-2 can activate the phosphorated adenosine 5'-monophosphate (AMP)-activated protein kinase α (p-AMPK), phosphoinositide 3-kinase p110α (PI3K-p110α), and phosphorated glycogen synthase kinase-3ß (Ser9) (p-GSK3ß). CONCLUSION: These results indicating that the SZJ-1 and SZJ-2 might improve the insulin resistant symptoms by improving the energy metabolic level and increasing the glycogen synthase activity of HepG2 cells.


Assuntos
Insulinas , Saponinas , Ziziphus , Extratos Vegetais/farmacologia , Hipoglicemiantes/farmacologia , Fosfatidilinositol 3-Quinases , Saponinas/farmacologia
7.
J Comb Optim ; 45(3): 83, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36968846

RESUMO

In this paper, we study a stock-rationing queue with two demand classes by means of the sensitivity-based optimization, and develop a complete algebraic solution to the optimal dynamic rationing policy. We show that the optimal dynamic rationing policy must be of transformational threshold type. Based on this finding, we can refine three sufficient conditions under each of which the optimal dynamic rationing policy is of threshold type (i.e., critical rationing level). To do this, we use the performance difference equation to characterize the monotonicity and optimality of the long-run average profit of this system, and thus establish some new structural properties of the optimal dynamic rationing policy by observing any given reference policy. Finally, we use numerical experiments to demonstrate our theoretical results of the optimal dynamic rationing policy. We believe that the methodology and results developed in this paper can shed light on the study of stock-rationing queue and open a series of potentially promising research.

8.
Int J Biol Macromol ; 184: 380-392, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126149

RESUMO

Russula virescens is an edible wild mushroom that is widely distributed in south of China. This research aimed to analyze the structure characterization and evaluate the hypoglycemic, anticancer and immunological activities of two water soluble polysaccharides RVP-1 and RVP-2 from R. virescens. The results showed RVP-1 and RVP-2 were non-triple helix structured hetero-polysaccharides with different weight-average molecular weight 14,883 and 13,301 Da, respectively. Both RVP-1 and RVP-2 were composed of galactose, glucose, mannose and fructose, and the sugar residues were mainly linked by 1,6→, 1,2→, 1→ and 1,3,6→ glycosidic bonds. Moreover, the antidiabetic, anticancer and immune activities of RVP-1 and RVP-2 were explored in vitro methods. The two polysaccharides have potential for inhibiting α-glucosidase and α-amylase activities, suppressing HepG-2, A549 and MCF-7 cancer cells proliferation, and activating macrophage RAW 264.7 cells to secret immune cytokines for mediating cellular immune response. These findings provided a scientific basis for further utilization of polysaccharide from R. virescens.


Assuntos
Antineoplásicos/química , Antioxidantes/química , Basidiomycota/química , Citocinas/metabolismo , Polissacarídeos Fúngicos/química , Hipoglicemiantes/química , Células A549 , Animais , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Sequência de Carboidratos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Polissacarídeos Fúngicos/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Células Hep G2 , Humanos , Hipoglicemiantes/farmacologia , Células MCF-7 , Camundongos , Peso Molecular , Células RAW 264.7 , alfa-Amilases/antagonistas & inibidores
9.
Nat Commun ; 11(1): 4481, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901004

RESUMO

Chemical fixation of carbon dioxide (CO2) may be a pathway to retard the current trend of rapid global warming. However, the current economic cost of chemical fixation remains high because the chemical fixation of CO2 usually requires high temperature or high pressure. The rational design of an efficient catalyst that works at ambient conditions might substantially reduce the economic cost of fixation. Here, we report the rational design of covalent organic frameworks (COFs) as efficient CO2 fixation catalysts under ambient conditions based on the finding of "pore enrichment", which is concluded by a detailed investigation of the 10994 COFs. The best predicted COF, Zn-Salen-COF-SDU113, is synthesized, and its efficient catalytic performance for CO2 cycloaddition to terminal epoxide is confirmed with a yield of 98.2% and turnover number (TON) of 3068.9 under ambient conditions, which is comparable to the reported leading catalysts. Moreover, this COF achieves the cycloaddition of CO2 to 2,3-epoxybutane under ambient conditions among all porous materials. This work provides a strategy for designing porous catalysts in the economic fixation of carbon dioxide.

10.
Appl Opt ; 59(16): 4790-4795, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32543471

RESUMO

In this paper, the self-absorption of InGaN quantum wells at high photon density is studied based on a rectangular ridge structure. The ridge structure was fabricated based on a standard GaN-based blue LED wafer grown on (0001) patterned sapphire substrate. The high-density photons were obtained by a high-power femtosecond laser with high excitation of 42kW/cm2 at room temperature. Based on the analysis of the photoluminescence intensities of the InGaN quantum wells, we found that the absorption coefficient of the InGaN quantum wells varies with the background photon density. The results revealed that the final absorption coefficient of the InGaN quantum well decreases with the increase of photon density, which can be 48.7% lower than its normal value under our experimental conditions.

11.
Oncol Lett ; 15(4): 5849-5858, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29552214

RESUMO

The Wnt/ß-catenin pathway serves important roles in cancer development. The expression and function of Chibby (Cby), as a direct antagonist of ß-catenin, in nasopharyngeal carcinoma (NPC) has not been fully investigated. The present study revealed that the mRNA and protein expression of Cby was significantly lower in NPC tissue than in the adjacent normal tissue. Low expression of Cby was significantly associated with the tumor and the clinical staging. Furthermore, Cby overexpression inhibited the proliferation of human NPC SUNE1 cells and induced cell cycle arrest. In addition, Cby overexpression also significantly enhanced the susceptibility of SUNE1 cells to apoptosis. These results indicated that Cby might serve as an anti-oncogenic gene in the development of NPC and could represent a potential therapeutic target for the human NPC therapy.

12.
Environ Int ; 88: 133-141, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26735351

RESUMO

The incidence of breast cancer is related to various risk factors, especially that the environmental and lifestyle factors account for major contribution at the rate of 70% to 95% over all. However, there still remains some controversy over the epidemiological evidence regarding the effects of environmental carcinogens on the risk of breast cancer. We conducted a quantitative meta-analysis aiming at full evaluation of the effects of polychlorinated biphenyls (PCBs) on breast cancer in a congener-specific fashion. Four online literature databases were systematically searched before 1st January 2015, for studies stating correlation between PCB congeners and breast cancer. The Newcastle-Ottawa Scale was used to evaluate the quality of the studies that were included in our analysis. Sixteen studies were included in our final meta-analysis after screening based on the priori inclusion criteria. Nine PCB congeners were reported by more than two studies and they were presented in detail. The pooled Odds Ratios (ORs) showed a significant increase in the risk of breast cancer in individuals with higher plasma/fat levels of PCB 99 (OR: 1.36; 95% CI: 1.02 to 1.80), PCB 183 (OR: 1.56; 95% CI: 1.25 to 1.95) and PCB 187 (OR: 1.18; 95% CI: 1.01 to 1.39). Besides, the outcomes did not support a relationship between dioxin-like PCB congeners and the risk of breast cancer. The results of our meta-analysis imply that PCB 99, PCB 183 and PCB 187 would increase the risk of breast cancer. The mechanism of this increased risk may be by the induction of the CYP2B family in cytochrome P450 enzymes.


Assuntos
Neoplasias da Mama/induzido quimicamente , Poluentes Ambientais/toxicidade , Bifenilos Policlorados/toxicidade , Neoplasias da Mama/epidemiologia , Poluentes Ambientais/análise , Feminino , Humanos , Incidência , Razão de Chances , Bifenilos Policlorados/análise , Fatores de Risco
13.
Huan Jing Ke Xue ; 36(3): 1037-44, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-25929074

RESUMO

Ninety-nine topsoil (0-15 cm) samples were collected from Kaifeng City, China using the grid method, and then the concentrations of As, Cd, Cr, Cu, Ni, Pb and Zn in the samples were measured by standard methods. Soil pollution levels and potential ecological risks of the heavy metals were assessed using the pollution load index (PLI) and potential ecological risk index (RI), respectively. Ordinary Kriging interpolation technique was employed to investigate the spatial distribution of PLI and RI of the city. The results showed that high pollution of Cd occurred in Kaifeng urban soils, and there was moderate pollution of Zn, slight pollution of Pb and Cu, and no pollution of Ni, Cr and As. Very high ecological risk was posed by Cd and low risk by other metals. The mean PLI of the 7 metals from all sample points was 2.53, which was categorized as moderate pollution. The average RI was 344.58 which represented a considerable ecological risk. PLI and RI shared a similar spatial distribution with high values centralized in the old industrial area in the southeast and railway stations for passengers and goods in the south of the city, followed by the old town within the ancient city wall, and low values located in the north and west areas. Cadmium was the main factor for both soil pollution and potential ecological risk primarily due to farmland topsoil in the eastern suburb of Kaifeng City with high Cd concentrations resulted from sewage irrigation deposited in the urban area by wind, human activities such as soot discharged from the chemical fertilizer plant of Kaifeng, transportation and coal combustion.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , Solo/química , Cádmio , China , Cidades , Medição de Risco , Esgotos
14.
Huan Jing Ke Xue ; 35(3): 1068-74, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-24881398

RESUMO

Nine residential communities which were built on different brownfields in a city of Henan Province were chosen to investigate the health risks of heavy metals (As, Hg, Cd, and Pb) in surface soils. Concentrations of soil heavy metals were measured according to the methods described in the national standard. Based on the health risk models recommended by the U. S. Environmental Protection Agency (US EPA), non-carcinogenic and carcinogenic health risks of soil heavy metals were assessed. The results showed that compared with the original brownfields, the heavy metal concentrations in soils and their health risks in residential communities built on brownfields were significantly improved, and the concentrations and health risks of soil heavy metals in these communities were all higher than those in non-brownfield residential communities. The HQ and HI values of soil heavy metals in all the residential communities were lower than 1, which indicated that there was no non-carcinogenic risk in these communities. Meanwhile, the values of CR and TCR were slightly higher than the standard suggested by the US EPA, indicating that slight carcinogenic risks in the communities, but these values were lower than the lenient standard proposed by some experts. The HI value of the four metals for children was exactly seven times higher than that for adults. The contribution rate of HQ(As) to HI was about 75%, CR(AS) to TCR was about 80%, and therefore arsenic was the crucial factor for carcinogenic and non-carcinogenic risk in the residential communities of the city.


Assuntos
Monitoramento Ambiental , Poluição Ambiental/efeitos adversos , Metais Pesados/análise , Poluentes do Solo/análise , Adulto , Criança , Cidades , Humanos , Medição de Risco , Solo/química , Poluentes do Solo/normas
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