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1.
Curr Pharm Biotechnol ; 25(4): 510-519, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37957921

RESUMO

Background: Ligand-mediated liposomes targeting folate receptors (FRs) that are overexpressed on the surface of tumor cells may improve drug delivery. However, the properties of liposomes also affect cellular uptake and drug release.

Objective: Mitoxantrone folate targeted liposomes were prepared to increase the enrichment of drugs in tumor cells and improve the therapeutic index of drugs by changing the route of drug administration.

Methods: Liposomes were prepared with optimized formulation, including mitoxantrone folatetargeted small unilamellar liposome (MIT-FSL), mitoxantrone folate-free small unilamellar liposome (MIT-SL), mitoxantrone folate-targeted large unilamellar liposome (MIT-FLL), mitoxantrone folate-free large unilamellar liposomes (MIT-LL). Cells with different levels of folate alpha receptor (FRα) expression were used to study the differences in the enrichment of liposomes, the killing effect on tumor cells, and their ability to overcome multidrug resistance.

The results of the drug release experiment showed that the particle size of liposomes affected their release behavior. Large single-compartment liposomes could hardly be effectively released, while small single-compartment liposomes could be effectively released, MIT-FSL vs MIT-FLL and MIT-SL vs MIT-LL had significant differences in the drug release rate (P<0.0005). Cell uptake experiments results indicated that the ability of liposomes to enter folic acid receptor-expressing tumor cells could be improved after modification of folic acid ligands on the surface of liposomes and it was related to the expression of folate receptors on the cell surface. There were significant differences in cell uptake rates (p<0.0005) for cells with high FRα expression (SPC-A-1 cells), when MIT-FSL vs MIT-SL and MIT-FLL vs MIT-LL. For cells with low FRα expression (MCF-7 cells), their cell uptake rates were still different (p<0.05), but less pronounced than in SPC-A-1 cells. The results of the cell inhibition experiment suggest that MIT-FLL and MIT-LL had no inhibitory effect on cells, MIT-FSL had a significant inhibitory effect on cells and its IC50 value was calculated to be 4502.4 ng/mL, MIT-SL also had an inhibitory effect, and its IC50 value was 25092.1 ng/mL, there was a statistical difference (p<0.05), MIT-FSL had a higher inhibitory rate than MIT-SL at the same drug concentration. Afterward, we did an inhibitory experiment of different MIT-loaded nanoparticles on MCF-7 cells compared to the drug-resistant cells (ADR), Observing the cell growth inhibition curve, both MIT-FSL and MIT-SL can inhibit the growth of MCF-7 and MCF-7/ADR cells. For MCF- 7 cells, at the same concentration, there is little difference between the inhibition rate of MITFSL and MIT-SL, but for MCF-7/ADR, the inhibition rate of MIT-FSL was significantly higher than that of MIT-SL at the same concentration (P<0.05).

Conclusion: By modifying folic acid on the surface of liposomes, tumor cells with high expression of folic acid receptors can be effectively targeted, thereby increasing the enrichment of intracellular drugs and improving efficacy. It can also change the delivery pathway, increase the amount of drug entering resistant tumor cells, and overcome resistance.

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Assuntos
Lipossomos , Mitoxantrona , Humanos , Mitoxantrona/farmacologia , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Proteínas de Transporte/metabolismo , Ligantes , Ácido Fólico
2.
Front Pharmacol ; 14: 1243613, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954849

RESUMO

The tumor microenvironment affects the structure and metabolic function of mitochondria in tumor cells. This process involves changes in metabolic activity, an increase in the amount of reactive oxygen species (ROS) in tumor cells compared to normal cells, the production of more intracellular free radicals, and the activation of oxidative pathways. From a practical perspective, it is advantageous to develop drugs that target mitochondria for the treatment of malignant tumors. Such drugs can enhance the selectivity of treatments for specific cell groups, minimize toxic effects on normal tissues, and improve combinational treatments. Mitochondrial targeting agents typically rely on small molecule medications (such as synthetic small molecules agents, active ingredients of plants, mitochondrial inhibitors or autophagy inhibitors, and others), modified mitochondrial delivery system agents (such as lipophilic cation modification or combining other molecules to form targeted mitochondrial agents), and a few mitochondrial complex inhibitors. This article will review these compounds in three main areas: oxidative phosphorylation (OXPHOS), changes in ROS levels, and endogenous oxidative and apoptotic processes.

3.
Chin Med J (Engl) ; 136(10): 1188-1197, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37083119

RESUMO

BACKGROUND: Pneumonia-like primary pulmonary lymphoma (PPL) was commonly misdiagnosed as infectious pneumonia, leading to delayed treatment. The purpose of this study was to establish a computed tomography (CT)-based radiomics model to differentiate pneumonia-like PPL from infectious pneumonia. METHODS: In this retrospective study, 79 patients with pneumonia-like PPL and 176 patients with infectious pneumonia from 12 medical centers were enrolled. Patients from center 1 to center 7 were assigned to the training or validation cohort, and the remaining patients from other centers were used as the external test cohort. Radiomics features were extracted from CT images. A three-step procedure was applied for radiomics feature selection and radiomics signature building, including the inter- and intra-class correlation coefficients (ICCs), a one-way analysis of variance (ANOVA), and least absolute shrinkage and selection operator (LASSO). Univariate and multivariate analyses were used to identify the significant clinicoradiological variables and construct a clinical factor model. Two radiologists reviewed the CT images for the external test set. Performance of the radiomics model, clinical factor model, and each radiologist were assessed by receiver operating characteristic, and area under the curve (AUC) was compared. RESULTS: A total of 144 patients (44 with pneumonia-like PPL and 100 infectious pneumonia) were in the training cohort, 38 patients (12 with pneumonia-like PPL and 26 infectious pneumonia) were in the validation cohort, and 73 patients (23 with pneumonia-like PPL and 50 infectious pneumonia) were in the external test cohort. Twenty-three radiomics features were selected to build the radiomics model, which yielded AUCs of 0.95 (95% confidence interval [CI]: 0.94-0.99), 0.93 (95% CI: 0.85-0.98), and 0.94 (95% CI: 0.87-0.99) in the training, validation, and external test cohort, respectively. The AUCs for the two readers and clinical factor model were 0.74 (95% CI: 0.63-0.83), 0.72 (95% CI: 0.62-0.82), and 0.73 (95% CI: 0.62-0.84) in the external test cohort, respectively. The radiomics model outperformed both the readers' interpretation and clinical factor model ( P <0.05). CONCLUSIONS: The CT-based radiomics model may provide an effective and non-invasive tool to differentiate pneumonia-like PPL from infectious pneumonia, which might provide assistance for clinicians in tailoring precise therapy.


Assuntos
Linfoma , Pneumonia , Humanos , Estudos Retrospectivos , Pneumonia/diagnóstico por imagem , Análise de Variância , Tomografia Computadorizada por Raios X , Linfoma/diagnóstico por imagem
4.
Ann Transl Med ; 11(2): 51, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36819550

RESUMO

Background: To investigate the biosynthesis and pharmacokinetic course of enteric-coated soft capsules of Panax notoginseng saponins (PNS) in a beagle dog model. Methods: To satisfy the enteric properties of soft capsules, the PNS enteric soft gelatin capsules were prepared by formaldehyde impregnation and orthogonal experimental design. The fluidity of gelatin and the disintegration time were selected as evaluation indexes; the soft gelatin capsule content was self-emulsifying, and the Km value and the optimal prescription were determined by making three-phase diagrams; in vivo pharmacokinetics studies were performed on six beagle dogs with 3 dogs in each group. Beagle dogs were divided into two groups randomly. One group was given PNS self-emulsifying enteric capsule and the other was given market conventional capsules. Plasma samples were collected at different times. After 1 week, the crossover experiment was carried out. The plasma concentration was detected by HPLC-MS (high performance liquid chromatography-mass spectrometry). Then the pharmacokinetic parameters were calculated by non-compartment model analysis. Results: The range and variance analysis of the orthogonal test determined that the best prescription of total saponins of Panax notoginseng enteric soft capsule was:gelatin:glycerol:water =1:1:2, Soak the films in 1% formaldehyde for 1 hour. The contents of the soft capsule self-microemulsion are prescribed as: IPM (isopropyl myristate):Cremophor RH40:PEG400 (polyethylene glycol 400) =1:4.5:4.5 (with suitable PNS); the pharmacokinetic parameters of PNS self-emulsified enteric capsules and conventional capsules in the market are as follows: Rb1:Cmax is (18.05±0.26) and (15.50±0.51) ng/mL, Tmax is (2.00±0) and (3.00±0) h, AUC0→t is 98.49±1.16 and 34.46±2.02 (ng/mL)·h, relative bioavailability is 196.2%; Rg1: Cmax is 4.16±0.25 and 3.88±0.28 ng/mL, Tmax is 2.00±0 and 1.50±0 h, area under drug time curve (AUC)0→t is 11.80±2.93 and 10.45±2.29 (ng/mL)·h, relative bioavailability is 77.2%; R1:Cmax is 1.84±0.25 and 1.48±0.21 ng/mL, Tmax is 2.08±0.49 and 1.92±0.20 h, AUC0→t is 7.06±2.07 and 7.16±2.59 (ng/mL)·h, relative bioavailability is 117.7%. Conclusions: The experiment in vivo showed the higher relative bioavailability of PNS self-emulsifying enteric capsule compared with market conventional capsules. This will provide a potential application prospect for the clinical research and applications of PNS.

5.
Res Int Bus Finance ; 60: 101581, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34840399

RESUMO

In this study, we provide evidence suggesting that in countries with severe disaster experience (SDE), the response to the coronavirus disease 2019 (COVID-19) pandemic is characterized by a higher level of attention in the population, more timely market responses, and stricter government containment measures. Specifically, we find that during the first COVID-19 outbreak in Wuhan, China, people in countries with SDE searched for related information more frequently on Google than did people in countries with mild disaster experience (MDE). Moreover, we find that a higher level of attention to COVID-19, as measured by Google search index usage, led to greater declines in stock market indexes in countries with SDE than in those with MDE. Finally, we find that compared with countries with MDE, those with SDE implemented more stringent social distancing policies in response to domestic COVID-19 outbreaks, and individuals in the latter group of countries were more likely to follow government-imposed rules of social distancing in both the early outbreak and reopening phases. Our findings suggest that disaster experience increases risk aversion and is an essential mechanism by which individuals, markets, and countries respond to COVID-19 in a timely manner.

6.
Anim Nutr ; 5(4): 407-409, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31890918

RESUMO

This experiment was to investigate ginger extract on production performance, antioxidant ability and immunity of laying hens. A total of 600 Hy-Line brown laying hens aged at 25 wk old were randomly divided into 2 treatments, 4 replicates per treatment, 75 layers each replicate. The control group hens were fed a basal diet; the experimental group hens were fed basal diets with 0.1% ginger extract. The results were shown as follows: 1) ginger extract significantly enhanced laying rates (P < 0.05) and daily egg weight (P < 0.05), substantially reduced the ratio of feed to egg (P < 0.05) of the hens; 2) ginger extract did not change the activities of glutathione peroxidase (GSH-PX) and total antioxidant capacity (TAOC) but significantly improved plasma superoxide dismutase (SOD) activity (P < 0.05), reduced malondialdehyde (MDA) content (P < 0.05) of the birds; 3) ginger extract did not affect the contents of serum total protein (TP), albumin (ALB), globulin (GLB), but significantly increased lysozyme (LZM) activity (P < 0.05); 4) ginger extract also significantly reduced plasma prostaglandin E2 (PGE2) content (P < 0.05). This study shows that ginger extract not only can improve the birds' antioxidant capacity, enhance immune function, but also has a potential of reducing inflammatory response.

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