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1.
Talanta ; 236: 122840, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635230

RESUMO

Ultrasensitive detection of biomarkers at an early stage is generally limited by external influence factors such as high reaction temperature, complex operations, and sophisticated instruments. Here, we circumvent these problems by using nicotinamide adenine dinucleotide (NAD+) to control electroinitiated reversible addition fragmentation chain transfer (electro-RAFT) polymerization for biosensing that enables the detection of a few molecules of target DNA. In this coenzyme-catalyzed electro-RAFT polymerization, numerous ferrocenylmethyl methacrylate (FCMMA) as monomer with electrochemistry signal were linked to the biomarker on Au electrode. Afterwards, a strong oxidation peak appears at the potential of about 0.3 V that represents a typical oxidation potential of FCMMA. The sensitivity of this methodology was presented by detecting DNA from 10-1 to 104 fM concentration and detection limit (LOD) being down to 4.39 aM in 10 µL samples. This is lower by factors than detection limits of most other ultra-sensitive electrochemical DNA assays.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Catálise , Coenzimas , DNA , Polimerização
2.
Cell Tissue Res ; 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34729647

RESUMO

Human embryonic stem cells (hESCs) are self-renewing and pluripotent cells that originate from the inner cell mass of the blastocyst. Mitosis is fundamental to organism survival and reproduction and is responsible for the equal distribution of duplicated chromosomes into daughter cells. Mitotic dysfunction is associated with a wide variety of human diseases, not least cancer. hESCs have a unique cell cycle distribution, but it is unclear exactly how the mitotic activity of hESCs is related to their proliferation and differentiation. Here, we established a cell line of hESCs stably expressing GFP-α-tubulin and mCherry-H2B by lentiviral infection to analyze and visualize mitosis in detail. During metaphase, the mitotic spindle was smaller and wider and contained a greater proportion of astral microtubules than normal cells. In addition, spindle microtubules were more stable, and chromosome alignment was faster in hESCs than in somatic cells. We also found that the spindle assembly checkpoint was functional in hESCs. These findings thus reveal a specialized mitotic behavior of hESCs.

3.
Sci Total Environ ; : 151364, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34740668

RESUMO

Atmospheric particles are important reaction vessels for multiphase chemistry. We conducted a meta-analysis of previous field observations in various environments (includes ocean, urban and rural regions), showing that particle hygroscopicity inhomogeneity (PHI) is ubiquitous for the continental atmospheric particles, in which a considerable part of the particulate matters is hydrophobic (10%-33% on average). However, the effects of PHI in quantifying the uptake process of reactive gases are still unclear. Here, taking N2O5 uptake as an example, we showed that using a laboratory-based parameterization scheme without considering the PHI might result in a misestimation of uptake rate coefficient, especially under low ambient relative humidity (RH). Such misestimation may be caused by the differences of the uptake coefficients, as well as the proportion of surface area concentration (SA) between hydrophilic and hydrophobic particles. We suggested that the PHI should be well-considered in establishing the reactive traces gases heterogeneous uptake parameterizations.

4.
Food Funct ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34813638

RESUMO

This paper aimed to study the effect of the phenol-rich fraction from Chinese sumac fruits on ethanol-induced gastric ulcers in mice and to further elucidate the potential mechanisms. The results showed that the phenol-rich fraction of the fruits significantly decreased the ulcer index, restored the levels of prostaglandin E-2, heat shock protein 70, glutathione and superoxide dismutase, and reduced the malondialdehyde content. Further analyses revealed that the fraction significantly alleviated the gastric oxidative stress by upregulating the Nrf2 protein pathway to increase the HO-1 and NQO1 expression levels, suppressed the inflammation by reducing the expression levels of p-NF-κB and p-IκBα and inhibited the secretion of tumor necrosis factor-α, interleukin-1ß, and interleukin-6. In addition, the fraction remarkably prevented gastric mucous cell apoptosis by upregulating Bcl-2 and downregulating Bax and cleaved caspase3. This experiment clarified for the first time that the phenol-rich fraction from Chinese sumac fruits can prevent ethanol-induced gastric ulcers in mice by inhibiting the oxidative stress, inflammatory response and cell apoptosis. The results obtained from the current work indicated that the phenol-rich fraction from Chinese sumac fruits could be applied as a kind of natural resource for producing new functional foods to prevent and/or improve gastric ulcers induced by ethanol.

5.
Front Pharmacol ; 12: 706220, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803669

RESUMO

Gut microbiota plays important roles in several metabolic processes, such as appetite and food intake and absorption of nutrients from the gut. It is also of great importance in the maintenance of the health of the host. However, much remains unknown about the functional mechanisms of human gut microbiota itself. Here, we report the identification of one anticancer gut bacterial strain AD16, which exhibited potent suppressive effects on a broad range of solid and blood malignancies. The secondary metabolites of the strain were isolated and characterized by a bioactivity-guided isolation strategy. Five new compounds, streptonaphthalenes A and B (1-2), pestaloficins F and G (3-4), and eudesmanetetraiol A (5), together with nine previously known compounds, were isolated from the effective fractions of AD16. Structures of the new compounds were established by 1D and 2D NMR and MS analysis, and the absolute configurations were determined by the CD method. The analysis of network pharmacology suggested that 3, 2, and 13 could be the key components for the anti-NSCLC activity of AD16. In addition to the PI3K-Akt signaling pathway, the proteoglycans in cancer pathway could be involved in the anti-NSCLC action of AD16.

6.
Int Immunopharmacol ; 101(Pt A): 108308, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34741870

RESUMO

BACKGROUND: Aim of this study is investigates the influence of spiperone on hydrolase activity pathway in chronic obstructive pulmonary disease (COPD). PATIENTS AND METHODS: Differentially expressed genes (DEGs) were calculated by the limma package from microarray data GSE20257, and analysed via gene set enrichment analysis (GSEA) for identifying COPD related pathways. The regulation of hydrolase activity pathway related drugs was predicted by connectivity Map analysis (CMap). Western blotting and reverse transcription quantitative polymerase chain reaction (RT-qPCR) were used to investigate the effect of spiperone on regulation of hydrolase activity pathway in vitro experiment. RESULTS: A total of 378 DEGs were identified by the limma package. GSEA suggested that the regulation of hydrolase activity pathway was involved in the development of COPD. CMap of hub genes of regulation of hydrolase activity pathwayshown the most significant compound was spiperone. Results of vitro experiment verify that cigarette smoke extract (CSE) can increase the expression of fibronectin 1 (FN1) and epidermal growth factor (EGF), coinsided with decrease the expression of chemokine (C-X3-C motif) ligand 1 (CX3CL1), chemokoine (C-C motif) ligand 20 (CCL20), complement component 3 (C3) and slithomolog 2 (SLIT2) in BESA-2B cells and U937 cells. Spiperone can reverse the effect of CSE in BESA-2B cells and U937 cells. CONCLUSION: Regulation of hydrolase activity pathway was involved in the occurrence of COPD, spiperone was a potential drug for the treatment of COPD by affecting the regulation of hydrolase activity pathway. This study had provided new insights into the potential pathogenesis and treatment of COPD.

7.
J Thorac Dis ; 13(10): 5899-5910, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34795938

RESUMO

Background: Previous studies have shown the feasibility and effectiveness of local aggressive thoracic therapy (surgery and radiotherapy) for oligometastatic non-small cell lung cancer compared with systemic therapy, but with small sample. This study aims to perform a pooled analysis to explore whether LT could improve outcomes of oligometastatic patients with non-small cell lung cancer. Methods: Protocol of present study was registered on PROSPERO as number: CRD42021233095. PubMed, Embase and Web of knowledge were searched, and eligible studies investigating local therapy for non-small cell lung cancer with 1-5 metastases regardless of organs were included. Linear regression between survival and clinical characteristics were conducted. Hazard ratios of survival and adverse effects were merged. Pooled survival curves were carried out. Results: Three randomized controlled trials and 5 cohort studies enrolling 499 patients were included. There was a trend that median overall survival declined with the increasing proportion of N2-3 positive patients in local therapy group, but with no statistical difference (P=0.09, R2=0.98). Undergoing local therapy for oligometastatic non-small cell lung cancer achieved reduction of 47% and 60% in the risk of death and cancer progression (P<0.001), respectively. In subgroup analysis, patients receiving local therapy including surgery showed hazard ratio of 0.33 on progression-free survival and 0.55 of these excluding surgery. Patients receiving consolidative local therapy (local therapy after systemic therapy) obtained hazard ratios 0.33 and 0.45 on progression-free and overall survival vs. systemic therapy, respectively. Hazard ratios of those receiving upfront local therapy (local therapy first) were 0.62 and 0.68 on progression-free and overall survival vs. systemic therapy. Pooled survival analysis showed median overall and progression-free survival of local therapy (21.6 and 14 months) group were both longer than systemic one (14.3 and 6.5 months). Odds ratio of adverse effects were no difference between 2 groups (P=0.16). Conclusions: Local aggressive thoracic therapy could prolong 7 months overall and progression-free survival compared with systemic therapy in patients with oligometastatic non-small cell lung cancer. Consolidative local therapy might be a more favorable choice of local therapy. Benefits of local therapy for N2-3 positive patients should explored further.

8.
World J Clin Cases ; 9(28): 8413-8424, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34754850

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a common autoimmune disease. Nursing education for family caregivers is considered a workable and effective intervention, but the validity of this intervention in RA has not been reported. AIM: To explore whether family caregiver nursing education (FCNE) works on patients with RA and the factors that influence FCNE. METHODS: In this randomized controlled study, a sample of 158 pairs was included in the study with 80 in the intervention group and 78 in the control group. Baseline data of patients and caregivers was collected. The FCNE intervention was administered to caregivers, and inflammation level indicators, disease activity indicators and mood disorder indicators of patients were followed up and analyzed. RESULTS: Baseline characteristics of the intervention and the control groups had no significant difference. Indicators were significantly reduced in the intervention group compared to the control group. The intervention group showed significant differences in stratification of relationship, education duration and age. CONCLUSION: The effect of FCNE on RA is multifaceted, weakening inflammation level, alleviating disease activity and relieving mood disorder. Relationship between caregiver and patient, caregiver's education level and patient's age may act as impact factors of FCNE.

9.
Front Pharmacol ; 12: 672065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707493

RESUMO

Background and Objective: Corticosteroid resistance is a major barrier to chronic obstructive pulmonary disease (COPD), but the exact mechanism of corticosteroid resistance in COPD has been less well studied. Methods: The microarray dataset GSE11906, which includes genomic and clinical data on COPD, was downloaded from the Gene Expression Omnibus (GEO) database, and the differentially expressed genes (DEGs) were identified using R software. Gene set enrichment analysis (GSEA) and Kyoto Encyclopedia of Genes (KEGG) were utilized to enrich and analyze the gene cohort related to the response to steroid hormones, respectively. The Connectivity Map (CMap) database was used to screen corticosteroid resistance-related drugs that might exert a potential therapeutic effect. STRING was used to construct a protein-protein interaction (PPI) network of the gene cohort, and the CytoHubba plug-in of Cytoscape was used to screen the hub genes in the PPI network. The expression levels of hub genes in cigarette smoke extract (CSE)-stimulated bronchial epithelial cells were assayed by quantitative real-time PCR and western blotting. Results: Twenty-one genes were found to be correlated with the response to steroid hormones. In the CMap database, 32 small-molecule compounds that might exert a therapeutic effect on corticosteroid resistance in COPD were identified. Nine hub genes were extracted from the PPI network. The expression levels of the BMP4, FOS, FN1, EGFR, and SPP1 proteins were consistent with the microarray data obtained from molecular biology experiments. Scopoletin significantly restrained the increases in the levels of AKR1C3, ALDH3A1, FN1 and reversed the decreases of phosphorylated GR and HDAC2 caused by CSE exposure. Conclusion: The BMP4, FOS, FN1, EGFR, and SPP1 genes are closely correlated with CSE-induced glucocorticoid resistance in airway epithelial cells. Scopoletin may be a potential drug for the treatment of glucocorticoid resistance caused by CSE.

10.
Nat Methods ; 18(11): 1342-1351, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34711970

RESUMO

Recent advances in spatially resolved transcriptomics (SRT) technologies have enabled comprehensive characterization of gene expression patterns in the context of tissue microenvironment. To elucidate spatial gene expression variation, we present SpaGCN, a graph convolutional network approach that integrates gene expression, spatial location and histology in SRT data analysis. Through graph convolution, SpaGCN aggregates gene expression of each spot from its neighboring spots, which enables the identification of spatial domains with coherent expression and histology. The subsequent domain guided differential expression (DE) analysis then detects genes with enriched expression patterns in the identified domains. Analyzing seven SRT datasets using SpaGCN, we show it can detect genes with much more enriched spatial expression patterns than competing methods. Furthermore, genes detected by SpaGCN are transferrable and can be utilized to study spatial variation of gene expression in other datasets. SpaGCN is computationally fast, platform independent, making it a desirable tool for diverse SRT studies.

11.
Am J Med Genet A ; 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34617658

RESUMO

Disco-interacting protein 2 C (DIP2C) encodes a disco-interacting protein and is highly expressed in the nervous system. Most variants of DIP2C are microdeletions on chromosome 10p15.3. This study reports a 17-month-old infant with focal infantile epilepsy who has a single-nucleotide variation in DIP2C that results in alternative splicing. The de novo variation (NM_014974.3: c.1057+2T>G) in DIP2C was uncovered through whole-exome sequencing. Minigene assays were performed and verified the alternative splicing caused by the variation. Finally, an 80-bp nucleotide deletion in the 3' end of Exon 8 was detected. Our study identified a de novo splicing variant that affects the coding length of DIP2C. This finding provides a new candidate gene for focal infantile epilepsy. Importantly, our finding is the first to associate a single nucleotide variant in DIP2C with focal infantile epilepsy.

12.
J Ethnopharmacol ; 284: 114752, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34662665

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: According to traditional Chinese medicine and a previous literature, many parts of Chinese sumac (Rhus chinensis Mill.), including fruits, are used as traditional herb to prevent or cure many diseases, such as inflammation, diarrhea, malaria, and other acute or chronic gastrointestinal diseases. However, the effects of the fruits on the prevention of gastric ulcer and the underlying mechanisms have not been reported. AIM OF THE STUDY: This experiment aimed to investigate the preventive effect of ethanol extract (RM) from Chinese sumac fruits on indomethacin-induced gastric ulcer in mice and the underlying mechanisms. MATERIALS AND METHODS: A single gavage of indomethacin was used to induce a gastric ulcer model in Kunming male mice. According to the results of histopathological analysis, immunohistochemistry and immunofluorescence analysis, as well as the expression of prostaglandin E-2, antioxidant enzymes and cytokines, the protective effect of RM on indomethacin-induced gastric ulcer was evaluated. The expression levels of several key proteins involved in oxidative stress, inflammation and apoptosis in gastric tissue were detected to illuminate the underlying mechanisms. RESULTS: RM significantly reduced the ulcer index and pepsin activity, improved the microstructure of gastric mucosa and the prostaglandin E-2 content, restored the levels of glutathione and superoxide dismutase, and decreased the contents of malondialdehyde, advanced oxidation protein products, TNF-α, IL-1 ß and IL-6. Further experimental results showed that RM could improve the expression levels of HO-1 and NQO1 by activating the Nrf2 protein pathway to alleviate oxidative stress in gastric tissue. At the same time, RM significantly down-regulated the expressions of p-NF-κB, p-IκBα and iNOS to relieve inflammatory response, and inhibited the cellular apoptosis of gastric tissue by up-regulating Bcl-2 and down-regulating Bax and cleaved Caspase-3. CONCLUSIONS: The current work clarified that the ethanol extract from Chinese sumac fruits can improve the oxidative stress level, inflammatory response and cell apoptosis in gastric tissue by interfering with the expressions of several key regulatory proteins to prevent indomethacin-induced gastric ulcer in mice. This study may provide some insights and scientific evidence on the application of Chinese sumac fruits as a traditional herb to prevent or alleviate gastric ulcer.

13.
Food Funct ; 12(20): 9965-9978, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34494061

RESUMO

The purpose of this research was to explore the preventive effect of an 80% ethanol extract of Rhus chinensis Mill. fruits on dextran sulfate sodium (DSS)-induced colitis in mice and to elucidate the underlying molecular mechanisms of this effect. The results indicated that the extract, especially when administered at a high dose, could dramatically decrease the disease activity index, maintain normal spleen conditions, and improve colonic histopathology and length in the DSS-induced mice. In addition, extract administration could significantly suppress the levels of malondialdehyde, myeloperoxidase, tumor necrosis factor-α, interleukin-1ß, and interleukin-6 and enhance superoxide dismutase and glutathione levels. The extract obviously protected intestinal barrier integrity by improving Occludin, ZO-1 and Claudin-1 expression levels. Western blot and immunohistochemistry analyses further indicated that the preventive effect of the phenol-rich extract on DSS-induced colitis might be achieved through the up-regulation of the expression of several pivotal oxidative stress-associated proteins, namely Nrf2, NQO1 and HO-1, and the down-regulation of the expression of several pivotal inflammation-associated proteins, namely p-NF-κB, p-IκB, COX-2, iNOS, p-P38, p-Erk1/2, and p-JNK. Therefore, R. chinensis fruits extract possesses the capability to prevent DSS-induced ulcerative colitis in mice and could be utilized as a natural substance in the exploitation of functional foods as an adjuvant dietary therapy for preventing and/or alleviating inflammatory bowel disease.

14.
Clin Hemorheol Microcirc ; 79(1): 217-230, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34487028

RESUMO

Human induced pluripotent stem cells (hiPSCs) are a promising cell source to generate the patient-specific lung organoid given their superior differentiation potential. However, the current 3D cell culture approach is tedious and time-consuming with a low success rate and high batch-to-batch variability. Here, we explored the establishment of lung bud organoids by systematically adjusting the initial confluence levels and homogeneity of cell distribution. The efficiency of single cell seeding and clump seeding was compared. Instead of the traditional 3D culture, we established a 2.5D organoid culture to enable the direct monitoring of the internal structure via microscopy. It was found that the cell confluence and distribution prior to induction were two key parameters, which strongly affected hiPSC differentiation trajectories. Lung bud organoids with positive expression of NKX 2.1, in a single-cell seeding group with homogeneously distributed hiPSCs at 70% confluence (SC_70%_hom) or a clump seeding group with heterogeneously distributed cells at 90% confluence (CL_90%_het), can be observed as early as 9 days post induction. These results suggest that a successful lung bud organoid formation with single-cell seeding of hiPSCs requires a moderate confluence and homogeneous distribution of cells, while high confluence would be a prominent factor to promote the lung organoid formation when seeding hiPSCs as clumps. 2.5D organoids generated with defined culture conditions could become a simple, efficient, and valuable tool facilitating drug screening, disease modeling and personalized medicine.

15.
Clin Hemorheol Microcirc ; 79(1): 205-216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34487031

RESUMO

BACKGROUND: Polymeric materials have been widely used as artificial grafts in cardiovascular applications. These polymeric implants can elicit a detrimental innate and adaptive immune response after interacting with peripheral blood. A surface modification with components from extracellular matrices (ECM) may minimize the activation of immune cells from peripheral blood. The aim of this study is to compare the cellular response of blood-born immune cells to the fiber meshes from polyesteretherurethane (PEEUm) and PEEUm with ECM coating (PEEUm + E). MATERIALS AND METHODS: Electrospun PEEUm were used as-is or coated with human cardiac ECM. Different immune cells were isolated form human peripheral blood. Cytokine release profile from naïve and activated monocytes was assessed. Macrophage polarization and T cell proliferation, as indication of immune response were evaluated. RESULTS: There was no increase in cytokine release (IL-6, TNF-α, and IL-10) from activated monocytes, macrophages and mononuclear cells on PEEUm; neither upon culturing on PEEUm + E. Naïve monocytes showed increased levels of IL-6 and TNF-α, which were not present on PEEUm + E. There was no difference on monocyte derived macrophage polarization towards pro-inflammatory M1 or anti-inflammatory M2 on PEEUm and PEEUm + E. Moreover, T cell proliferation was not increased upon interacting with PEEUm directly. CONCLUSION: As PEEUm only elicits a minimal response from naïve monocytes but not from monocytes, peripheral blood mononuclear cells (PBMCs) or T cells, the slight improvement in response to PEEUm + E might not justify the additional effort of coating with a human ECM.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34542065

RESUMO

Multiblock copolymers type PDC are polyetheresterurethanes composed of poly(ɛ-caprolactone) and poly(p-dioxanone) segments. They were designed as degradadable shape-memory polymers for medical devices, which can be implanted minimally-invasively. While providing structural support in the initial phase after implantation, they are capable to modulate soft tissue regeneration while degradation. In this perspective, we elucidate cell-material interactions, compatibility both in-vitro and in-vivo and biofunctionality of PDC, which represents a promising candidate biomaterial family especially for cardiovascular applications.

17.
J Ethnopharmacol ; 281: 114519, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34390795

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Taraxacum platycarpum Dahlst. (Korean dandelion) is a medicinal herb used in traditional medicine in Korea to treat various disease such as furuncles, mammitis, hepatitis, jaundice. Moreover, a decoction prepared from T. platycarpum leaves and stems is an effective treatment for cancer, glycosuria, liver disease, pleurodynia, and stomach problems. AIM OF THE STUDY: The main objective of this work was to study the composition and structural properties of polysaccharides (TPP) from Taraxacum platycarpum Dahlst. root and investigate the immunostimulatory activity on RAW264.7 cells. MATERIALS AND METHODS: TPP was extracted from T. platycarpum using hot water extraction, ethanol precipitation method and its fractionated using DEAE-Sepharose fast flow column. The composition, molecular weight, and structural characterization of TPP and its fractions were evaluated by various techniques. Further, the immunostimulatory activity of polysaccharides was tested on murine macrophage cell line RAW264.7 by various in vitro assays. The structure effect of TPP on RAW264.7 cells was studied by the removal of sulfate (desulfation) and protein (deproteinization) contents from TPP. RESULTS: We obtained three fractions namely TPP-1, TPP-2, and TPP-3 which mainly consisted of carbohydrates (75.55, 52.71, and 48.41%), sulfate (8.42, 15.19, and 27.67%), uronic acid (1.27, 6.56, and 4.39%), and protein (8.15, 24.85, and 9.73%). The average molecular weight of the fractions was 56.7, 108.2, and 132.3 × 103 g/mol, respectively. The polysaccharides activate the RAW264.7 cell to produce a significant amount of NO and upregulate the various mRNA expression by the activation of MAPK and NF-κB pathways via TLR4, TLR2, and CR3 receptors. The structurally modified deproteinated derivative (DP-TPP-2) more effectively decreases the NO production which means the protein content of TPP-2 mainly contributes to the RAW264.7 cells activation. The structure of DP-TPP-2 primarily consists of 1 â†’ 2)-Galp, 1 â†’ 6)-Glup, 1 â†’ 2) - Rhap, and 1 â†’ 5) - Arap glycosidic linkages. CONCLUSIONS: The present study demonstrated that the polysaccharide isolated from T. platycarpum shows admirable immunostimulatory by the activation of MAPK and NF-κB pathways through TLR4, TLR2, and CR3 receptors. The protein content of polysaccharides mainly contributes to the RAW264.7 cells activation. Our study results could be useful for developing a new immunostimulant agent.

18.
Biofabrication ; 13(4)2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34340226

RESUMO

Elimination of residual osteosarcoma cells and repair of bone defects remain major challenges for osteosarcoma in clinic. To address this problem, it is required that multifunctional therapeutic platform possess high tumor-killing efficiency and simultaneous bone regeneration capabilities. In this work, an intelligent therapeutic platform was developed to achieve highly-efficient tumor therapy and simultaneous significantly improved bone defect repairing ability, which was realized byin situgrowing ferromagnetic Fe3S4layers with tuned microstructures on the surface of 3D-printed akermanite bioceramic scaffolds via hydrothermal method. The Fe3S4layers exploited magnetic thermal energy to enhance chemodynamic treatment, thus achieving a synergistic effect between magnetothermal and chemodynamic therapy on the elimination of residual tumor cells. Moreover, the micro-structured surface of the 3D-printed bioceramic scaffolds further enhanced the osteogenic activityin vitroand accelerated the bone regenerationin vivo. The scaffolds with multi-mode tumor-killing and bone repairing capabilities indicated that such a therapeutic platform is applicable for a stepwise treatment strategy of osteosarcoma and provides inspiration for the design of multifunctional biomaterials.

19.
Langmuir ; 37(36): 10657-10667, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34449220

RESUMO

Bacterial infection and blockage are severe problems for polyurethane (PU) catheters and there is an urgent demand for surface-functionalized polyurethane. Herein, a cationic alternating copolymer comprising allyl-substituted ornithine and glycine (allyl-substituted poly(Orn-alter-Gly)) with abundant carbon-carbon double bond functional groups (C═C) is designed. Polyurethane is prepared with a large quantity of C═C groups (PU-D), and different amounts of allyl-substituted poly(Orn-alter-Gly) are grafted onto the PU-D surface (PU-D-2%AMPs and PU-D-20%AMPs) via the C═C functional groups. The chemical structures of the allyl-substituted poly(Orn-alter-Gly) and polyurethane samples (PU, PU-D, PU-D-2%AMPs, and PU-D-20%AMPs) are characterized and the results reveal that allyl-substituted poly(Orn-alter-Gly) is decorated on the polyurethane. PU-D-20%AMPs shows excellent antibacterial activity against Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus because of the high surface potential caused by cationic allyl-substituted poly(Orn-alter-Gly), and it also exhibits excellent long-term antibacterial activity and antibiofilm properties. PU-D-20%AMPs also has excellent antifouling properties because the cationic copolymer is fixed at multiple reactive sites, thus avoiding the formation of movable long chain brush. A strong surface hydration barrier is also formed to prevent adsorption of proteins and ions, and in vivo experiments reveal excellent biocompatibility. This flexible strategy to prepare dual-functional polyurethane surfaces with antibacterial and antifouling properties has large potential in biomedical implants.


Assuntos
Incrustação Biológica , Poliuretanos , Antibacterianos/toxicidade , Incrustação Biológica/prevenção & controle , Peptídeos/farmacologia , Poliuretanos/toxicidade , Staphylococcus aureus , Propriedades de Superfície
20.
Fitoterapia ; 154: 105022, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34438014

RESUMO

Four previously undescribed glutamic acid derivatives, verticillamines A-D (1-4), together with six known compounds (5-10) were isolated from the bulbs of Fritillaria verticillate Willd. The structures of (1-10) were established on the basis of UV, IR, MS, 1D and 2D NMR, and the absolute configurations of compounds (1-4) were determined by calculated ECD methods. Among them, compounds (1-3) were rare 2-methyl-γ-lactam alkaloid derivatives. Moreover, both γ-lactam alkaloids (1-5) and pyrrolidine alkaloids (6-7) were discovered in Fritillaria for the first time. Compound 8 exhibited moderate cytotoxic activities against A2780 and HepG 2 cells, with IC50 values of 11.7 ± 5.2 µM and 25.6 ± 2.8 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Fritillaria/química , Glutamatos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , China , Glutamatos/isolamento & purificação , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química
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