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1.
J Colloid Interface Sci ; 607(Pt 2): 1153-1162, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34571302

RESUMO

Transition metal oxalates have attracted wide attention due to the characteristics of the conversion reaction as anode materials in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), However, there are huge volume expansion and sluggish circulation dynamics during the reversible Li+ and Na+ insertion/extraction process, which would lead to unsatisfactory reversible capacity and stability. In order to solve these problems, a rod-like structure Ni0.5Co0.5C2O4·2H2O is in-situ formed on the reduced graphene oxide layer (Ni0.5Co0.5C2O4·2H2O/rGO) in a glycol-water mixture medium via an interface induced engineering strategy. Benefitting from the synergistic cooperation of nano-diameter rod-like structure and high conductive rGO networks, the experimental results show that the prepared Ni0.5Co0.5C2O4·2H2O/rGO electrode has predominant rate performance and ultra-long cycle stability. For the LIBs, it not only exhibits an ultrahigh reversible capacity (1179.9 mA h g-1 at 0.5 A g-1 after 300 cycles), but also presents outstanding rate and cycling performance (646.5 mA h g-1 at 5 A g-1 after 1200 cycles). Besides, the Ni0.5Co0.5C2O4·2H2O/rGO electrode displays remarkable sodium storage capacity of 221.6 mA h g-1 after 100 cycles at 0.5 A g-1. Further, the extraordinary electrochemical capability of Ni0.5Co0.5C2O4·2H2O/rGO active material is also reflected in two full-cells, assembled using commercial LiCoO2 as cathode for LIBs and commercial Na3V2(PO4)3 as cathode for SIBs, both of which can show wonderful specific capacity and cycling stability. It is found in in-situ Raman experiments that the reversible changes of oxalate peaks are monitored in a charge/discharge process, which is scientific evidence for the transform reaction mechanism of metal oxalates in LIBs. These findings not only provide important ideas for studying the charge/discharge storage mechanism but also give scientific basis for the design of high-performance electrode materials.

2.
Food Chem ; 371: 131075, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34543926

RESUMO

The adulteration of meat products has been reported worldwide, and detection of specific peptides through mass spectrometry (MS) is a reliable method for meat species identification. However, the practical application of this method is limited by complicated steps and long reaction time of the traditional sample preparation. Therefore, this paper introduced a convenient and time-saving sample preparation by optimizing the steps of reduction, alkylation, digestion, and purification. With the rapid sample preparation, 35 species-specific peptides for seven species (pig, cattle, sheep, deer, chicken, duck, and turkey) were screened using high-resolution MS, and a rapid LC-MS/MS method was established. The method only takes 3 h from sample receipt to results. The meat species of 20 processed meat products were detected, and three samples were found potentially adulterated. The method is proved to have high sensitivity, specificity, practicability with respect to rapid identification of meat species in meat products.


Assuntos
Cervos , Produtos da Carne , Animais , Bovinos , Cromatografia Líquida , Carne/análise , Produtos da Carne/análise , Ovinos , Suínos , Espectrometria de Massas em Tandem
3.
Sci Total Environ ; 806(Pt 1): 150247, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34562762

RESUMO

Observations of volatile organic compounds (VOCs) are a prerequisite for evaluating the effectiveness of government efforts targeting VOC pollution. Here, based on the one-year online VOC measurement in 2018 in Beijing, systematic analyses and model simulation were conducted to illuminate VOC characteristics, emission sources, regional hotspots and behaviours in response to O3 formation. The observed mean VOC concentration in 2018 was 29.12 ± 17.64 ppbv declined distinctly compared to that in 2015 and 2016. Vehicle exhaust (39.95%), natural gas/liquefied petroleum gas (22.04%) and industrial sources (20.64%) were the main contributors to VOCs in Beijing. Regional transport, mainly from the south-south-east (SSE) and south-south-west (SSW), quantitatively contributed 36.65%-55.06% to VOCs based on our developed method. O3 sensitivity tended to be in the transition regime in summer identified by ground-based and satellite observations. Strong solar radiation along with high temperature and low humidity aggravated O3 pollution that was further intensified by regional transport from southern polluted regions. The model simulation determined that turning off CH3CHO related reactions brought about the most predominantly short-term and long-run O3 reduction, indicating that control policies in VOC species should be tailored, instead of one-size-fits-all. Overall, region-collaborated and active VOC-species-focused strategies on VOC controls are imperative.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Ozônio/análise , Compostos Orgânicos Voláteis/análise
4.
Chemosphere ; 287(Pt 2): 132218, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34509769

RESUMO

Bisphenol analogues (BPs), triclocarban (TCC), and triclosan (TCS) are well-known environmental endocrine disrupters. Many studies have characterized their occurrence in the freshwater environment. However, their environmental behaviors in the coastal marine environment remain poorly understood. Here, matched seawater and sediment samples were collected from East China Sea, and analyzed for 13 BPs (including halogenated derivatives of bisphenol A), TCC, and TCS. Bisphenol A (BPA; mean 23 ng/L) was the predominant BP in seawaters, followed by tetrabromobisphenol A (TBBPA; 2.3 ng/L) and bisphenol S (BPS; 2.2 ng/L). Seawater concentrations of TCS (

Assuntos
Carbanilidas , Triclosan , Compostos Benzidrílicos/análise , Carbanilidas/análise , China , Fenóis , Água do Mar , Triclosan/análise
5.
Food Chem ; 372: 131336, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34818744

RESUMO

Over the years, food adulteration has become an important global problem, threatening public health safety and the healthy development of food industry. This study established a liquid chromatography-tandem mass (LC-MS/MS) method for accurate identification and quantitative analysis of fox meat products. High-resolution mass was used for data collection, and Proteome Discoverer was used for data analysis to screen fox-specific peptides. Multivariate statistical analysis was conducted using the data obtained from the label-free analysis of different contents of simulated samples. Samples with different contents were distinguished without interfering with each other, suggesting the feasibility of quantitative analysis of fox meat content. The linear correlation coefficient and recovery rate were calculated to determine the fox peptides that can be used for accurate quantification. The established LC-MS/MS method can be used for the accurate identification and quantification of actual samples. In addition, this method can provide technical support for law enforcement departments.


Assuntos
Produtos da Carne , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Raposas , Carne/análise , Produtos da Carne/análise , Espectrometria de Massas em Tandem
6.
Talanta ; 238(Pt 1): 123037, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34857317

RESUMO

This work describes the unique design of a bidirectional activatable synergetic DNA machine (BAS-DNA machine) for speeded and ultrasensitive determination of microRNA-21 (miR-21), a well-known biomarker for biomedical research and early diagnosis of lung cancer. The BAS-DNA machine is composed by a pair of track strands (Track 1 and Track 2) encoding with two regions in the opposite direction for miR-21 recognition. Introduction of miR-21 can hybridize either with Track 1 or with Track 2 to activate the BAS-DNA machine with a synergistic effect for speeded amplifying the fluorescence signal. Moreover, compared with common DNA machine with only one switch for exogenous target recognition, the BAS-DNA machine with two switches for miR-21 binding allows the speeded and strong operation of the autonomous strand scission, replication, and displacement on Track 1 and Track 2 simultaneously. This behavior makes the BAS-DNA machine powerful for ultrasensitive, specific, and fast screening of miR-21 even from real biological samples, and the fluorescence signal was found to be linear from 1 pM to 10 nM with a detection limit of 703.6 fM. We envision this BAS-DNA machine with its superior assay performance will provide a new avenue for simple, sensitive, and affordable biomedical assays.

7.
Thorac Cancer ; 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34850570

RESUMO

BACKGROUND: Circular RNAs (circRNAs) participate in the genesis and progression of tumors, including non-small cell lung cancer (NSCLC). At present, the role and regulatory mechanisms of circRNAs in NSCLC have not been fully elucidated. The aim of this study was to explore the role and regulatory mechanism of circRNA hsa_circ_0008037 (circ_0008037) in NSCLC. METHODS: Expression of circ_0008037 in NSCLC tissues and cells was detected by quantitative real-time polymerase chain reaction (RT-qPCR). Loss-of-function experiments were performed to analyze the influence of circ_0008037 knockdown on proliferation, migration, invasion, and the Warburg effect of NSCLC cells. Western blotting was utilized for protein analysis. The regulatory mechanism of circ_0008037 was surveyed by bioinformatics analysis, RNA pulldown assay, and dual-luciferase reporter assay. Xenograft assay was used to validate the oncogenicity of circ_0008037 in NSCLC in vivo. RESULTS: Circ_0008037 was upregulated in NSCLC tissues and cells. Circ_0008037 downregulation reduced tumor growth in vivo and repressed proliferation, migration, invasion, and decreased the Warburg effect of NSCLC cells in vitro. Mechanically, circ_0008037 regulated nuclear ubiquitous casein kinase and cyclin-dependent kinase substrate 1 (NUCKS1) expression via sponging miR-433-3p. Furthermore, MiR-433-3p inhibitor reversed the inhibiting influence of circ_0008037 silencing on proliferation, migration, invasion, and the Warburg effect of NSCLC cells. Also, NUCKS1 elevation overturned the repressive influence of miR-433-3p mimic on proliferation, migration, invasion, and the Warburg effect of NSCLC cells. CONCLUSION: Circ_0008037 accelerated tumor growth and elevated the Warburg effect via regulating NUCKS1 expression by adsorbing miR-433-3p, providing an underlying target for NSCLC treatment.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34848306

RESUMO

Probiotics could promote the healthy growth of aquatic animals and have been widely used in aquaculture. However, the influence of high concentration compound probiotics on the aquatic animals has not been reported. In the present study, a compound probiotics was used in high-density culture of crucian carps under the condition of micro-water exchange. During nearly 7-weeks feeding experiment, the aquaculture water quality, growth performances, disease resistance and microbiota distributions of crucian carps were tested. Under the high concentrations of compound probiotics, the content of total ammonia nitrogen and nitrite were finally in a state of dynamic equilibrium. The body length and weight of crucian carps in the experimental group (E) was significantly higher than that in the recirculating group (R). The antioxidant enzymes in the intestines and gills of the E group including SOD, CAT, GSH and MDA, were significantly higher than those in R group. The mortality of crucian carps in E group was significantly lower after the immersion infection of Aeromonas veronii. The addition of compound probiotics significantly increased the number of microorganisms detected in the intestines and gills of crucian carps in E group. The bacteria including Firmicutes, Planctomycetes, Verrucomicrobiota at the phylum level in E group were higher than those in R group. At the genus level, these bacteria (Pirellula, Roseimicrobium, Malikia) were not only higher in E group water, but also significantly higher in the intestines and gills than R group. The results of present study systematically analyzed the impact of high-concentration probiotics on crucian carps breeding, and speculated genus Pirellula, Roseimicrobium, Malikia may be used as aquatic probiotics. The present study will provide a new idea for the green and sustainable development of aquaculture.

9.
Opt Express ; 29(23): 37503-37514, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808820

RESUMO

We investigate band evolution of chiral and non-chiral symmetric flatband photonic rhombic lattices by applying a strain along the diagonal direction, and thereby demonstrating Landau-Zener Bloch (LZB) oscillations in the presence of a refractive index gradient. The chiral and non-chiral symmetric rhombic lattices are obtained by adding a detuning to uniform lattices. For the chiral symmetric lattices, the middle flatband is perturbed due to the chiral symmetry breaking while a nearly flatband appears as the bottom band with the increase of strain-induced next-nearest-neighbor hopping. Consequently, LZB oscillations exhibit intriguing characteristics such as asymmetric energy transitions and almost complete suppression of the oscillations. Nevertheless, for the non-chiral symmetric lattices, flatband persists owing to the retained particle-hole symmetry and evolves into the bottom band. Remarkably, the band gap can be readily tuned, which allows controlling of the amplitude of Landau-Zener tunneling (LZT) rate and may lead to thorough LZT. Our analysis provides an alternative perspective on the generation of tunable flatband and may also bring insight to study the symmetry and topological characterization of the flatband.

10.
Mol Pharm ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34816721

RESUMO

Gastric cancer (GC) is a common cancer worldwide, with high incidence and mortality rates. Therefore, early and precise diagnosis is critical to improving GC prognosis. Tumor-associated myeloid cells infiltrate the tumor microenvironment (TME) and can produce immunosuppressive effects in the early stage of the tumor. The surface integrin receptor CD11b is widely expressed in the specific subsets of myeloid cells, and it has the characteristics of high abundance, high specificity, and high potential for targeted immunotherapy. In this study, two strategies for labeling anti-CD11b, including 89Zr-DFO-anti-CD11b and pretargeted imaging (68Ga-NOTA-polypeptide-PEG11-Tz/anti-CD11b-TCO), were used to evaluate the value of early diagnosis of GC and confirm the advantages of the pretargeted strategy for the diagnosis of GC. Pretargeted molecular probe 68Ga-NOTA-polypeptide-PEG11-Tz was synthesized. The binding affinity of the Tz-radioligand to CD11b was evaluated in vitro, and its blood pharmacokinetic test was performed in vivo. Moreover, the anti-CD11b antibody was conjugated with a p-isothiocyanatobenzyl-desferrioxamine (SCN-DFO) chelator and radiolabeled with zirconium-89. Biodistribution and positron-emission computed tomography imaging experiments were performed in MGC-803 tumor-bearing model mice to evaluate the value of the early diagnosis of GC. Histological evaluation of MGC-803 tumors was conducted to confirm the infiltration of the GC TME with CD11b+ myeloid cells. 68Ga-NOTA-polypeptide-PEG11-Tz was successfully radiosynthesized, with the radiochemical purity above 95%, as confirmed by reversed-phase high-performance liquid chromatography. The radioligand showed favorable stability in normal saline and phosphate-buffered saline, good affinity to RAW264.7 cells, and rapid blood clearance in mice. The results of biodistribution and imaging experiments using the pretargeted method showed that the tumor/muscle ratios were 5.17 ± 2.98, 5.94 ± 1.46, and 4.46 ± 2.73 at the pretargeting intervals of 24, 48, and 72 h, respectively. The experimental results using the method of the directly labeling antibody (89Zr-DFO-anti-CD11b) showed that, despite radioactive accumulation in the tumor, there was a higher level of radioactive accumulation in normal tissues. The tumor/muscle ratios were 1.09 ± 0.67, 1.66 ± 0.95, 2.94 ± 1.24, 3.64 ± 1.21, and 3.55 ± 1.64 at 1, 24, 48, 72, and 120 h. The current research proved the value of 68Ga-NOTA-polypeptide-PEG11-Tz/anti-CD11b-TCO in the diagnosis of GC using the pretargeted strategy. Compared to 89Zr-DFO-anti-CD11b, the image contrast achieved by the pretargeted strategy was relatively improved, and the background accumulation of the probe was relatively low. These advantages can improve the diagnostic efficiency for GC and provide supporting evidence for radioimmunotherapy targeting CD11b receptors.

11.
Adv Immunol ; 152: 83-155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34844710

RESUMO

Neuropsychiatric diseases have traditionally been studied from brain, and mind-centric perspectives. However, mounting epidemiological and clinical evidence shows a strong correlation of neuropsychiatric manifestations with immune system activation, suggesting a likely mechanistic interaction between the immune and nervous systems in mediating neuropsychiatric disease. Indeed, immune mediators such as cytokines, antibodies, and complement proteins have been shown to affect various cellular members of the central nervous system in multitudinous ways, such as by modulating neuronal firing rates, inducing cellular apoptosis, or triggering synaptic pruning. These observations have in turn led to the exciting development of clinical therapies aiming to harness this neuro-immune interaction for the treatment of neuropsychiatric disease and symptoms. Besides the clinic, important theoretical fundamentals can be drawn from the immune system and applied to our understanding of the brain and neuropsychiatric disease. These new frameworks could lead to novel insights in the field and further potentiate the development of future therapies to treat neuropsychiatric disease.

12.
Biomater Sci ; 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34846053

RESUMO

The self-healing of chemotherapy-induced oral mucositis is difficult in practice because of both local bacterial infection and severe inflammation. Herein, in situ mucoadhesive hydrogels (PPP_E) were successfully prepared by using temperature-sensitive PLGA-PEG-PLGA (PPP) as a matrix and epigallocatechin-3-gallate (EGCG) with inherent antibacterial activity as an adhesion enhancer. A series of PPP_E precursor solutions with various EGCG concentrations (1%, 2% and 5%) were prepared by fixing the PPP concentration at 25%. EGCG slightly decreased the sol-gel transition temperature and shortened the sol-gel transition time of the PPP hydrogel. Moreover, the incorporation of EGCG could significantly increase the tissue adhesion properties of the PPP hydrogel at 37 °C. PPP_2%E displayed a suitable gelation temperature (36.2 °C), gelation time (100 s) and storage modulus (48 Pa). Tripeptide KPV as a model drug was easily dissolved in cold PPP_2%E precursor solution to prepare KPV@PPP_2%E hydrogel. The anti-inflammatory activity and promotion of cell migration potential by KPV in PPP-2% E hydrogel were well maintained. Moreover, KPV@PPP_2%E exhibited strong antibacterial efficacy against S. aureus. PPP_2%E precursor solution rapidly transformed to a hydrogel and adhered to the wound surface for 7 hours when administrated to the gingival mucosa of rats. Treatment with KPV@PPP_2%E hydrogel greatly improved the food intake and body weight recovery of rats with chemotherapy-induced oral mucositis. Moreover, the tissue morphology of the ulcerated gingiva after application of KPV@PPP_E hydrogel was also well repaired by promoting CK10 and PCNA expression. In addition, the inflammatory cytokines including IL-1ß and TNF-α were significantly inhibited by KPV@PPP_2%E hydrogel while IL-10 was up-regulated. KPV@PPP_2%E hydrogel also had an anti-bacterial effect on MRSA-infected gingival ulcer wounds, which resulted in the obvious inhibition of infiltration by inflammatory cells into submucosal tissues. Conclusively, KPV@PPP_E may be a promising practical application for cancer patients with chemotherapy-induced oral mucositis.

13.
ACS Biomater Sci Eng ; 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34757733

RESUMO

With the development of technology, adjuvant immunotherapy has become a promising strategy for prevention of postoperative tumor regression and metastasis by stimulating the host immune response. However, the therapeutic effects are still unsatisfactory due to the lack of synergy between different methods. In this study, an efficient synergistic immunotherapy system based on injectable sodium alginate hydrogels was designed to inhibit in situ recurrence and metastasis at the same time. On the one hand, an injectable sodium alginate (SA) hydrogel microsystem loaded with toll-like receptor (TLR) agonists (CpG ODNs) was synthesized for inhibiting in situ recurrence, and then carcinoembryonic antigen (CEA) probe was also added to detect CEA based on fluorescence resonance energy transfer (FRET) technology to monitor the occurrence and development of tumor recurrence. On the other hand, an anti-programmed cell death 1 ligand 1 antibody (anti-PD-L1)-modified SA nanogel loaded with indocyanine green (ICG@SA-anti-PD-L1 nanogel) was prepared for diagnosing and inhibiting lung metastasis by assisting orthotopic tumor therapy. In vitro and in vivo results demonstrated that this SA micro/nanosystem could monitor and inhibit postoperative recurrence and metastasis. We hope that this micro/nano-synergistic system will become an effective strategy for postoperative adjuvant immunotherapy.

14.
Genes (Basel) ; 12(11)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34828395

RESUMO

The biotrophic fungal pathogen Ustilago maydis causes common smut in maize, forming tumors on all aerial organs, especially on reproductive organs, leading to significant reduction in yield and quality defects. Resistance to U. maydis is thought to be a quantitative trait, likely controlled by many minor gene effects. However, the genes and the underlying complex mechanisms for maize resistance to U. maydis remain largely uncharacterized. Here, we conducted comparative transcriptome and metabolome study using a pair of maize lines with contrast resistance to U. maydis post-infection. WGCNA of transcriptome profiling reveals that defense response, photosynthesis, and cell cycle are critical processes in maize response to U. maydis, and metabolism regulation of glycolysis, amino acids, phenylpropanoid, and reactive oxygen species are closely correlated with defense response. Metabolomic analysis supported that phenylpropanoid and flavonoid biosynthesis was induced upon U. maydis infection, and an obviously higher content of shikimic acid, a key compound in glycolysis and aromatic amino acids biosynthesis pathways, was detected in resistant samples. Thus, we propose that complex gene co-expression and metabolism networks related to amino acids and ROS metabolism might contribute to the resistance to corn smut.

15.
Org Biomol Chem ; 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34842891

RESUMO

A copper-mediated 2,3-difunctionalization of indoles to afford 3-halogenated 2,3'-biindoles is described herein. The protocol uses readily available feedstocks and a naturally abundant copper catalyst system, which allows the regioselective formation of C-C and C-X (X = Cl & Br) bonds in one single operation. Here the copper metal salt serves not only as a catalyst but also as a reactant to provide the source of halogen. This operationally simple procedure avoids the utilization of environmentally unfriendly reagents and displays good functional group compatibility. Noteworthily, the introduction of halogen into molecules would offer great potential for further chemical transformations.

16.
J Hazard Mater ; 424(Pt C): 127549, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34736192

RESUMO

Studies have demonstrated the worldwide presence of bisphenol A (BPA) and its toxic effects on human health. BPA may exist as several structural isomers, which are byproducts in industrial BPA production. However, nearly nothing is known about the occurrence of BPA isomers in human blood and the partitioning of BPA metabolites between human serum and whole blood. In this study, BPA, BPA-sulfate (BPA-S), and BPA-glucuronide (BPA-G) were quantified in 144 pairs of serum and whole blood samples from Chinese participants. BPA was detected in 115 serum and 121 whole blood samples, with mean concentrations of 0.53 and 0.88 ng/mL, respectively. A structural isomer of BPA, tentatively termed B1-BPA, was identified for the first time, and measurable in 53% and 57% of serum (

17.
Adv Healthc Mater ; : e2102023, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812596

RESUMO

Neuromodulation is becoming more and more important in studying brain function, disease treatment, and brain-computer interfaces. However, traditional regulation methods cannot effectively achieve both wireless regulation and highly sensitive response, which are essential factors in neuromodulation. In this paper, a "magnetism-optogenetic" system is constructed, which uses a magnetic field to drive mechanoluminescent materials (ZnS:Cu) to generate light, thus stimulating photogenetic proteins. This system effectively combines the wireless magnetic regulation with the high sensitivity of optogenetics. The results show that the luminous intensity of this system changes with the power of an external magnetic field. In addition, under the continuous stimulation of the wireless magnetic field, this system can activate hippocampal-related neural responses and induce the expression of C-fos. In the end, this system can further regulate the movement behavior of rats with C1V1 protein expression in the primary motor cortex. This new magnetism-optogenetic system will provide an excellent reference for wireless and highly sensitive neuromodulation.

18.
Pharmaceutics ; 13(11)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34834192

RESUMO

Micelle is mainly used for drug delivery and is prepared from amphiphilic block copolymers. It can be formed into an obvious core-shell structure that can incorporate liposoluble drugs. However, micelles are not suitable for the encapsulation of water-soluble drugs, and it is also difficult to maintain stability in the systemic circulation. To solve these problems, a type of polymer material, Fmoc-Lys-PEG and Fmoc-Lys-PEG-RGD, was designed and synthesized. These copolymers could self-assemble into micelles driven by π-π stacking and the hydrophobic interaction of 9-fluorenylmethoxycarbony (Fmoc) and, at the same time, form a framework for a hydrogen-bonding environment in the core. Mitomycin C (MMC), as a water-soluble drug, can be encapsulated into micelles by hydrogen-bonding interactions. The interaction force between MMC and the polymers was analyzed by molecular docking simulation and Fourier transform infrared (FTIR). It was concluded that the optimal binding conformation can be obtained, and that the main force between the MMC and polymers is hydrogen bonding. Different types of MMC nanoparticles (NPs) were prepared and the physicochemical properties of them were systematically evaluated. The pharmacodynamics of the MMC NPs in vitro and in vivo were also studied. The results show that MMC NPs had a high uptake efficiency, could promote cell apoptosis, and had a strong inhibitory effect on cell proliferation. More importantly, the as-prepared NPs could effectively induce tumor cell apoptosis and inhibit tumor growth and metastasis in vivo.

20.
Zhongguo Zhong Yao Za Zhi ; 46(19): 4936-4944, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34738387

RESUMO

In this study, liquid chromatography-mass spectrometry(LC-MS) and high performance liquid chromatography(HPLC) were employed for qualitative and quantitative analysis of the steroidal saponins in rhizomes of Paris polyphylla var. yunnanensis from three different habitats cultured in vitro, in an attempt to explore whether the rhizomes of the medicinal herb cultured in vitro can synthesize the steroidal saponins, including polyphyllinsⅠ, Ⅱ, and Ⅶ, the quality markers specified in Chinese Pharmacopoeia(2020 edition). A total of 20 steroidal saponins were identified in the rhizomes from Changxin, Yunlong(S1), Fengyi, Dali(S2), and Niujie, Eryuan(S3): parisyunnanoside A and parisyunnanoside D or E, proto-polyphyllin Ⅱ, polyphyllins G and H, polyphyllinsⅠ, Ⅱ, Ⅴ, Ⅵ, and Ⅶ, dioscin, gracillin, prosapogenin A, Tg, isomer of Th, saponin Th, reclinatoside, proto-pairs D, pseudoproto-dioscin, and 23-O-glc-(23S,25R)-spirost-5-en-3ß,23α,27-triol-3-O-rha-(1→2)-[ara(1→4)]-glc or 27-O-glc-(23S,25R)-spirost-5-en-3ß,27α-diol-3-O-rha-(1→2)-[ara(1→4)]-glc. Among them, polyphyllinsⅠ, Ⅱ, and Ⅶ were detected in the rhizomes from S1, with the mass fraction of 0.109 1%, 0.165 2%, and 0.051 03%, respectively(total 0.325 3%). Polyphyllins Ⅱ and Ⅶ were identified in the rhizomes from S2 with the respective mass fraction of 0.192 2% and 0.074 23% and total content of 0.266 5%. Moreover, polyphyllins Ⅱ and Ⅶ were also found in the rhizomes from S3, which had the mass fraction of 0.207 7% and 0.186 9%, separately, with the total content of 0.394 6%. Thus, steroidal saponins, including the quality makers polyphyllins Ⅰ, Ⅱ, and Ⅶ recorded in Chinese Pharmacopoeia(2020 edition) can be synthesized in rhizomes of Paris polyphylla var. yunnanensis cultured in vitro, but their total content fails to meet the standard(0.60% in Chinese Pharmacopoeia). Therefore, in vitro culture of the Paris polyphylla var. yunnanensis is feasible, but the culture conditions need to be further improved.


Assuntos
Liliaceae , Melanthiaceae , Saponinas , Cromatografia Líquida de Alta Pressão , Rizoma
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