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BACKGROUND: The association between lipid and bone metabolism, particularly the role of high-density lipoprotein cholesterol (HDL-C) in regulating bone mineral density (BMD), is of significant interest. Despite numerous studies, findings on this relationship remain inconclusive, especially since evidence from large, sexually diverse Chinese populations is sparse. This study, therefore, investigates the correlation between HDL-C and lumbar BMD in people of different genders using extensive population-based data from physical examinations conducted in China. METHODS: Data from a cross-sectional survey involving 20,351 individuals aged > = 20 years drawn from medical records of health check-ups at the Health Management Centre of the Henan Provincial People's Hospital formed the basis of this study. The primary objective was to determine the correlation between HDL-C levels and lumbar BMD across genders. The analysis methodology included demographic data analysis, one-way ANOVA, subgroup analyses, multifactorial regression equations, smoothed curve fitting, and threshold and saturation effect analyses. RESULTS: Multifactorial regression analysis revealed a significant inverse relationship between HDL-C levels and lumbar BMD in both sexes, controlling for potential confounders (Male: ß = -8.77, 95% CI -11.65 to -5.88, P < 0.001; Female: ß = -4.77, 95% CI -8.63 to -0.90, P = 0.015). Subgroup and threshold saturation effect analyses indicated a stronger association in males, showing that increased HDL-C correlates with reduced lumbar BMD irrespective of age and body mass index (BMI). The most significant effect was observed in males with BMI > 28 kg/m2 and HDL-C > 1.45 mmol/L and in females with a BMI between 24 and 28 kg/m2. CONCLUSION: Elevated HDL-C is associated with decreased bone mass, particularly in obese males. These findings indicate that individuals with high HDL-C levels should receive careful clinical monitoring to mitigate osteoporosis risk. TRIAL REGISTRATION: The research protocol received ethics approval from the Ethics Committee at Beijing Jishuitan Hospital, in conformity with the Declaration of Helsinki guidelines (No. 2015-12-02). These data are a contribution of the China Health Quantitative CT Big Data Research team, registered at clinicaltrials.gov (code: NCT03699228).
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Densidade Óssea , HDL-Colesterol , População do Leste Asiático , Feminino , Humanos , Masculino , China , HDL-Colesterol/sangue , Estudos TransversaisRESUMO
Acylphosphatase 1 (ACYP1), a protein located in the mammalian cell cytoplasm, has been shown to be associated with tumor initiation and progression by functioning as a metabolism-related gene. Here we explored the potential mechanisms by which ACYP1 regulates the development of HCC and participates in the resistance to lenvatinib. ACYP1 can promote the proliferation, invasion, and migration capacities of HCC cells in vitro and in vivo. RNA sequencing reveals that ACYP1 markedly enhances the expression of genes related to aerobic glycolysis, and LDHA is identified as the downstream gene of ACYP1. Overexpression of ACYP1 upregulates LDHA levels, which then increases the malignancy potential of HCC cells. GSEA data analysis reveals the enrichment of differentially expressed genes in the MYC pathway, indicating a positive correlation between MYC and ACYP1 levels. Mechanistically, ACYP1 exerts its tumor-promoting roles by regulating the Warburg effect through activating the MYC/LDHA axis. Mass spectrometry analysis and Co-IP assays confirm that ACYP1 can bind to HSP90. The regulation of c-Myc protein expression and stability by ACYP1 is HSP90 dependent. Importantly, lenvatinib resistance is associated with ACYP1, and targeting ACYP1 remarkably decreases lenvatinib resistance and inhibits progression of HCC tumors with high ACYP1 expression when combined with lenvatinib in vitro and in vivo. These results illustrate that ACYP1 has a direct regulatory role in glycolysis and drives lenvatinib resistance and HCC progression via the ACYP1/HSP90/MYC/LDHA axis. Targeting ACYP1 could synergize with lenvatinib to treat HCC more effectively.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Glicólise/genética , Regulação Neoplásica da Expressão Gênica , MamíferosRESUMO
The Plasmodium falciparum proteasome is a potential antimalarial drug target. We have identified a series of amino-amide boronates that are potent and specific inhibitors of the P. falciparum 20S proteasome (Pf20S) ß5 active site and that exhibit fast-acting antimalarial activity. They selectively inhibit the growth of P. falciparum compared with a human cell line and exhibit high potency against field isolates of P. falciparum and Plasmodium vivax They have a low propensity for development of resistance and possess liver stage and transmission-blocking activity. Exemplar compounds, MPI-5 and MPI-13, show potent activity against P. falciparum infections in a SCID mouse model with an oral dosing regimen that is well tolerated. We show that MPI-5 binds more strongly to Pf20S than to human constitutive 20S (Hs20Sc). Comparison of the cryo-electron microscopy (EM) structures of Pf20S and Hs20Sc in complex with MPI-5 and Pf20S in complex with the clinically used anti-cancer agent, bortezomib, reveal differences in binding modes that help to explain the selectivity. Together, this work provides insights into the 20S proteasome in P. falciparum, underpinning the design of potent and selective antimalarial proteasome inhibitors.
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Compostos de Boro/farmacologia , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/química , Inibidores de Proteassoma/farmacologia , Administração Oral , Animais , Compostos de Boro/administração & dosagem , Compostos de Boro/química , Domínio Catalítico , Humanos , Malária Falciparum/enzimologia , Malária Falciparum/parasitologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Moleculares , Plasmodium falciparum/enzimologia , Inibidores de Proteassoma/administração & dosagem , Inibidores de Proteassoma/químicaRESUMO
Two-stage reverse osmosis (RO) processes with intermediate concentrate demineralization (ICD) provide an efficient strategy to treat brines with high CaSO4 contents and reduce concentrate discharge. In this paper, an SRO concentrate is treated using ICD to remove CaSO4 and then mixed with a PRO concentrate for further desalination in SRO, thereby reducing the discharge of the concentrate. We investigate the selection and degradation of scale inhibitors, as well as seeded precipitation in the two-stage RO process with ICD, to achieve a high water recovery rate. A scale inhibitor is added to restrain CaSO4 crystallization on the membrane surface, and the optimized scale inhibitor, RO-400, is found to inhibit calcium sulfate scaling effectively across a wide range of the saturation index of gypsum (SIg) from 2.3 to 6. Under the optimized parameters of 40 W UV light and 70 mg/L H2O2, UV/H2O2 can degrade RO-400 completely in 15 min to destroy the scale inhibitor in the SRO concentrate. After scale inhibitor degradation, the SRO concentrate is desaturated by seeded precipitation, and the reaction degree of CaSO4 reaches 97.12%, leading to a concentrate with a low SIg (1.07) for cyclic desalination. Three UVD-GSP cycle tests show that the reused gypsum seeds can also ensure the effect of the CaSO4 precipitation process. This paper provides a combined UVD-GSP strategy in two-stage RO processes to improve the water recovery rate for CaSO4-contained concentrate.
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The pathogenesis of postmenopausal osteoporosis (PMOP) is mainly determined by the adhesion of osteoclasts to the bone matrix and the involvement of various molecules in bone resorption. The dual regulation strategy of the physical barriers of bone matrix and intracellular gene regulation generated by advanced biomaterials is a decent alternative for the treatment of PMOP. Herein, for the first time, it is identified that hsa-miR-378i/mmu-miR-378a-3p are closely associated with PMOP. Then, an osteophilic and dual-regulated alendronate-gene lipoplex (antagomir@Aln-Lipo), composed of medicative alendronate-functionalized liposomal vehicle and encapsulated specific microRNAs is engineered, for bone-targeting delivery of genes to achieve combined mitigation of bone loss. Alendronate targets hydroxyapatite in the bone matrix and occupies the adhesion site of osteoclasts, thus providing the "physical barriers". Antagomir is coupled precisely to specific endogenous microRNAs, thus providing the "genetic signals". These functionalized lipoplexes exhibited long-term stability and good transfection efficiency. It is proven that antagomir@Aln-Lipo could synergistically regulate osteoclastogenesis and bone resorption in vitro and in vivo. Furthermore, intravenous injection of antagomir@Aln-Lipo efficiently reverses bone loss through a dual mechanism driven by alendronate and antagomir-378a-3p. In conclusion, the osteophilic and dual-regulated antagomir@Aln-Lipo offers a brand-new bifunctional strategy for the precise treatment of PMOP.
Assuntos
Reabsorção Óssea , MicroRNAs , Humanos , Alendronato , Antagomirs , Osso e Ossos/patologia , MicroRNAs/genéticaRESUMO
Novel polymers applied in economic membrane technologies are a perennial hot topic in the fields of natural gas purification and O2 enrichment. Herein, novel hypercrosslinked polymers (HCPs) incorporating 6FDA-based polyimide (PI) MMMs were prepared via a casting method for enhancing transport of different gases (CO2, CH4, O2, and N2). Intact HCPs/PI MMMs could be obtained due to good compatibility between the HCPs and PI. Pure gas permeation experiments showed that compared with pure PI film, the addition of HCPs effectively promotes gas transport, increases gas permeability, and maintains ideal selectivity. The permeabilities of HCPs/PI MMMs toward CO2 and O2 were as high as 105.85 Barrer and 24.03 Barrer, respectively, and the ideal selectivities of CO2/CH4 and O2/N2 were 15.67 and 3.00, respectively. Molecular simulations further verified that adding HCPs was beneficial to gas transport. Thus, HCPs have potential utility in fabrication of MMMs for facilitating gas transport in the fields of natural gas purification and O2 enrichment.
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Current best practice for the treatment of malaria relies on short half-life artemisinins that are failing against emerging Kelch 13 mutant parasite strains. Here, we introduce a liposome-like self-assembly of a dimeric artesunate glycerophosphocholine conjugate (dAPC-S) as an amphiphilic prodrug for the short-lived antimalarial drug, dihydroartemisinin (DHA), with enhanced killing of Kelch 13 mutant artemisinin-resistant parasites. Cryo-electron microscopy (cryoEM) images and the dynamic light scattering (DLS) technique show that dAPC-S typically exhibits a multilamellar liposomal structure with a size distribution similar to that of the liposomes generated using thin-film dispersion (dAPC-L). Liquid chromatography-mass spectrometry (LCMS) was used to monitor the release of DHA. Sustainable release of DHA from dAPC-S and dAPC-L assemblies increased the effective dose and thus efficacy against Kelch 13 mutant artemisinin-resistant parasites in an in vitro assay. To better understand the enhanced killing effect, we investigated processes for deactivation of both the assemblies and DHA, including the roles of serum components and trace levels of iron. Analysis of parasite proteostasis pathways revealed that dAPC assemblies exert their activity via the same mechanism as DHA. We conclude that this easily prepared multilamellar liposome-like dAPC-S with long-acting efficacy shows potential for the treatment of severe and artemisinin-resistant malaria.
Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Artesunato/farmacologia , Artesunato/uso terapêutico , Microscopia Crioeletrônica , Resistência a Medicamentos/genética , Humanos , Lipossomos/química , Malária/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Plasmodium falciparum/genéticaRESUMO
Bone defect regeneration depends on the population and lifespan of M2 macrophages, which are regulated by dual signals generated by the "physical" spatial configuration of biological tissues and "molecular" chemokines. Herein, inspired by the reprogramming of macrophages, immunoengineered porous microspheres are constructed to accelerate bone repair through the regulation of both "physical" and "molecular" signals. The porous structure of injectable poly (l-lactic acid) (PLLA) microspheres prepared by the microfluidic technique provides a "physical signal" for osteogenic differentiation. Additionally, interleukin (IL)-4-loaded liposomes (Ls) are modified on PLLA microspheres through amide bonds to produce IL-4/Ls/PLLA microspheres, providing a "molecular signal" in stimulating the differentiation of macrophages to M2 type. It is confirmed that IL-4/Ls/PLLA microspheres could induce M2-macrophages polarization and potentiate osteoblast proliferation and differentiation while coculturing with macrophages and osteoblasts in vitro. Besides, IL-4/Ls/PLLA microspheres are proved to promote bone defect regeneration by inducing the conversion of M1 macrophages to M2 through dual biosignal-functional regulation in both the calvaria defect and maxillary sinus defect models. Overall, the immuno-reprogrammed IL-4/Ls/PLLA microspheres achieve the precise immuno-reprogramming of macrophages by dual biosignal-functional regulation. This immune reengineering strategy paves a way for clinical bone defect treatment.
Assuntos
Interleucina-4 , Osteogênese , Regeneração Óssea/fisiologia , Microesferas , Osteoblastos , Poliésteres/químicaRESUMO
In this work, dimeric artesunate-phosphatidylcholine conjugate (dARTPC)-based liposomes encapsulated with irinotecan (Ir) were developed for anticancer combination therapy. First, dARTPC featured with unique amphipathic properties formed liposomes by classical thin-film methods. After that, Ir was encapsulated into dARTPC-based liposomes (Ir/dARTPC-LP) by the triethylammonium sucrose octasulfate gradient method. Physicochemical characterization indicated that Ir/dARTPC-LP had a mean size of around 140 nm and a negative ζ potential of approximately -30 mV. Most noticeably, liposomes displayed an encapsulation efficiency of greater than 98% with a controllable drug loading of 4-22%. The in vitro release of dihydroartemisinin (DHA) and Ir from Ir/dARTPC-LP was investigated by dialysis in different media. It was found that effective release of both DHA (65.42%) and Ir (77.28%) in a weakly acidic medium (pH 5.0) after 48 h was achieved in comparison to very slow release under a neutral environment (DHA 9.90% and Ir 8.72%), indicating the controllable release of both drugs. Confocal laser scanning microscopy confirmed the improved cellular internalization of Ir/dARTPC-LP. The cytotoxicity of Ir/dARTPC-LP was evaluated in the MCF-7, A549, and HepG2 cell lines. The results showed that Ir/dARTPC-LP had significant synergistic efficacy in the loss of cell growth. In vivo anticancer evaluation was performed using a 4T1 xenograft tumor model. Ir/dARTPC-LP had a high tumor inhibition rate of 62.7% without significant toxicity in comparison with the injection of Ir solution. Taken together, dARTPC encapsulated with Ir has great potential for anticancer combination therapy.
Assuntos
Artesunato/administração & dosagem , Sistemas de Liberação de Medicamentos , Irinotecano/administração & dosagem , Lipossomos/administração & dosagem , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Artesunato/farmacocinética , Artesunato/uso terapêutico , Linhagem Celular Tumoral , Combinação de Medicamentos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Irinotecano/farmacocinética , Irinotecano/uso terapêutico , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Neoplasias Experimentais/tratamento farmacológico , FosfatidilcolinasRESUMO
ß-Ga2O3 has recently attracted considerable attention for its application in resistive switching memory. However, the resistive behaviors and mechanisms of ß-Ga2O3 memory dominated by the oxygen-vacancy (VO) still remain controversial. In this study, we systemically investigated the formation process of VO conductive filaments in ß-Ga2O3 memory. There were at least three kinds of VOs and conductive filaments with different low resistance states (LRSs) in ß-Ga2O3 memory, suggesting their potential for multilevel storage application. Interestingly, these conductive filaments preferred to be formed along the [010] direction and with a single VO cluster rather than a mixed VO cluster due to the lower single VO cluster formation energy and ellipsoid charge distribution. The lowest migration and activation barriers for different kinds of VOs in +2 charge states (V2+Os) were discrepant and lower than the neutral charge states. Meanwhile, the forward migration energy of VO was different from the reversed migration path, so that the conductive filament formation and rupture were not an inverse process in the experiment. The detailed mechanisms were revealed by the charge density and migration process of these VOs. These results not only revealed the function of the VO conductive filaments in ß-Ga2O3 memory but also predicted the potential of ß-Ga2O3 memory for multilevel storage application.
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BACKGROUND: Several lines of evidence indicate that cold stimulation may not only activate brown adipose tissue (BAT) and the white adipose tissue (WAT), but also regulate the lipid metabolism and influence the development of atherosclerosis. However, the study of cold exposure affecting cholesterol metabolism have opposite results in different experiments, and Apolipoprotein E (ApoE) may play an important role. There is still a lack of complete research to illustrate this problem. METHODS: In this study, we first analyzed and discussed the activation of interscapular brown adipose tissue (iBAT), inguinal white adipose tissue (iWAT) and epididymal white adipose tissue (eWAT) under cold exposure (4 °C) in male wild-type C57BL/6 J (WT) and ApoE-deficient mice (ApoE-/-) fed high-fat diet (HFD) for 4 weeks. Subsequently, we investigated the effect of cold exposure on blood lipid profiles in both models. We further explored whether cold exposure can reduce serum cholesterol. RESULTS: In both WT and ApoE-/- mice, cold exposure activates iBAT and iWAT, as well as hardly affects eWAT. In WT mice,4 weeks cold exposure (4 °C) reduces serum triglyceride by 28%, cholesterol by 30% and LDL-cholesterol by 63%. In ApoE-/- mice, cold stimulation decreases serum triglyceride by 59%, but increases cholesterol by 20% and LDL-cholesterol by 25%. CONCLUSIONS: Based on these findings, we conclude that cold exposure decreases serum cholesterol is dependent upon the existence of ApoE.
Assuntos
Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/fisiologia , Apolipoproteínas E/fisiologia , Colesterol/sangue , Temperatura Baixa , Animais , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoERESUMO
The microtubule inhibitor paclitaxel (PTX) is used to treat a wide range of solid tumors. Due to the poor aqueous solubility of PTX, a continuous demand for safe, efficient PTX formulations with improved antitumor activity exists. Here, we report a novel form of redox-sensitive paclitaxel (PTX)-encapsulated liposomes based on the previously developed disulfide phosphatidylcholine (SS-PC). PTX-loaded stealth liposomes (PTX/SS-LP) composed of SS-PC, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-PEG2000 (DSPE-PEG2000), and cholesterol were prepared using the reverse-phase evaporation method. The characterization of the PTX/SS-LP liposomes using dynamic light scattering and transmission electron microscopy confirmed their uniform particle size and typical unilamellar vesicle structure with an average bilayer thickness of approximately 4 nm. Changes in the size and morphology as well as the rapid release of PTX triggered by the addition of dithiothreitol revealed the redox sensitivity of PTX/SS-LP. Finally, evaluations in MCF-7 and A549 cells in vitro and in BALB/c mice in vivo revealed the improved anticancer efficiency, biodistribution, and safety of PTX/SS-LP compared with those of Taxol and nonredox-sensitive PTX/LP. In conclusion, PTX/SS-LP displays a redox-responsive release of paclitaxel with improved antitumor activity and has great potential as a next-generation stealth liposomal PTX delivery system.
Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Lipossomos/química , Neoplasias/tratamento farmacológico , Paclitaxel/administração & dosagem , Fosfatidilcolinas/química , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Colesterol/química , Ditiotreitol , Liberação Controlada de Fármacos , Difusão Dinâmica da Luz , Humanos , Lipossomos/farmacologia , Lipossomos/toxicidade , Lipossomos/ultraestrutura , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Oxirredução/efeitos dos fármacos , Paclitaxel/química , Paclitaxel/farmacologia , Fosfatidilcolinas/síntese química , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Distribuição Tecidual , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
RIWVIWRR-NH2 (Bac8c) is a natural antimicrobial peptide (AMP) exhibiting great antibacterial activity against Gram-negative and Gram-positive bacteria. In this work, lipoic acid was used as a fatty acid hydrophobic ligand to modify Bac8c (LA-Bac8c) to further improve its antimicrobial properties. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) assays showed that LA-Bac8c exhibited lower MIC (MBC) values against Staphylococcus aureus (S. aureus) and methicillin-resistant Staphylococcus aureus (MRSA) than Bac8c. Similar results were reflected in the antibiofilm activity towards S. aureus and MRSA, and LA-Bac8c showed better activity to the biofilm which has been formed or is being formed. In addition to this, the obvious interaction between bacteria/biofilm and LA-Bac8c was observed by microscopy. LA-Bac8c displayed strong membrane depolarization and outer membrane permeabilizing ability, and the cell membrane treated with LA-Bac8c was destroyed to the leakage of bacteria cellular components. All these data indicated LA-Bac8c could be used as a useful antimicrobial peptide with wide application prospect.
Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Ácido Tióctico/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/química , Biofilmes/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Ácido Tióctico/químicaRESUMO
To evaluate the clinical efficacy and safety of berberine in the treatment of dyslipidemia. In this review, CNKI, WanFang, VIP, CBM, PubMed, Cochrane Library, EMbase, and Medline(OVID) were retrieved from database establishment to January, 2019 in any language. Randomized controlled trials(RCTs) of berberine with or without lipid-lowering drugs vs placebo, without drugs or lipid-lowering drugs only in treatment of dyslipidemia were collected. Data extraction and paper quality assessment were conducted according to the Cochrane Handbook. Then RevMan 5.3 software was used for Meta-analysis. A total of 25 trials were included, covering 3 042 cases, including 1 552 cases in the experimental group and 1 490 cases in the control group. The clinical heterogeneity of the included trials was relatively high, and the methodological quality of most trials was generally low, with bias in terms of random sequence generation, allocation hiding, blind method and result data. Interventions were divided into different subgroups for analysis. Meta-analysis suggested that use berberine alone or along with lipid lowing drugs could reduce TC, TG, LDL-C levels and increased HDL-C levels with statistically significant difference as compared with control group. As compared with control group, there was no statistically significant difference in the incidence of adverse events. No severe adverse effects were reported in all trials. Berberine has good efficacy and safety in the treatment of dyslipidemia. Due to the quality limitations of the included trials, the above conclusions need to be further verified by high-quality, large sample size and multi-center clinical trials.
Assuntos
Berberina/uso terapêutico , Dislipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Berberina/efeitos adversos , Humanos , Lipídeos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
The increasing application of gold nanoparticles (AuNPs) in biomedicine requires extensive investigation of surface modification and stabilization to maximize their advantages for the diversity of more challenging biological utilization. Herein, a thiol-mediated multifunctional phospholipid ligand was designed while disclosing a zwitterionic nature to AuNPs. The ligand was synthesized by attachment to two bidentate lipoic acid (LA) anchor groups and incorporation of a zwitterionic phosphatidylcholine (PC) group, allowing for excellent hydrophilicity. As demonstrated through ultraviolet-visible spectroscopy, appropriate 7 nm diameter AuNPs modified with a 1,2-dilipoyl-sn-glycero-3-phosphorylcholine (di-LA-PC) compact ligand exhibited the best colloidal stability in a high NaCl concentration of up to 217 mM, different temperatures, and a wide range of pH values from 3 to 11 when compared to the traditional surfactants or thiol-contained amino acid surface modification cases. These AuNPs are also stable without specific interaction to positively/negatively charged proteins, possibly leading to prolonged blood circulation after in vivo administration. Moreover, much more resistance to ligand competition of dithiothreitol was found than other thiol-coated AuNPs, which further highlighted their affinity in an aqueous system. Biocompatibility of the zwitterionic ligand di-LA-PC-modified AuNPs was finally evaluated by hemolysis and cytotoxicity tests. Cumulatively, the remarkable stability and biocompatibility of AuNPs, multicoordinated with a di-LA-PC ligand, potentially motivated them as a practical alternative for surface tailoring in biotechnology.
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Nanomedicines in polymeric therapeutics present a potential treatment for cancers. However, their clinical effectiveness still has room to be improved. Herein, reduction-responsive reversibly core-cross-linked micelles based on the poly(ethylene glycol)-dihydrolipoic acid (MeO-PEG2k-DHLA) conjugate were developed for triggered intracellular release of camptothecin (CPT). Coupling two molecules of dihydrolipoic acid (DHLA) to methyl-terminated PEG (Mw 2000) through a labile ester bond was performed by solution-phase condensation reaction. Due to the amphiphilic property, the MeO-PEG2k-DHLA conjugate formed micelles that were readily cross-linked with disulfide formation dispersed in water. These sole cross-linked micelles were 74.9 nm in hydrodiameter, as analyzed by dynamic light scattering (DLS). The nanostructures demonstrated excellent stability against extensive dilution, while rapidly dissociating under 10 mM glutathione (GSH), highlighting their potential for drug delivery. Interestingly, CPT was modified with a disulfide linkage and subsequently conjugated to the MeO-PEG2k-DHLA polymer scaffold. Core-cross-linking of the micelles achieved high drug loading of CPT (31.81%, wt %) and demonstrated that CPT release at pH 7.4 was significantly declined by cross-linking (i.e., less than 15% release in 24 h), whereas more than 90% of CPT was released under 10 mM GSH condition. In vitro cellular uptake and MTT assays showed that CPT-conjugated MeO-PEG2k-DHLA micelles were effectively internalized into tumor cells to induce the cytotoxic effects against HepG-2 and MCF-7 cells. Importantly, in vivo pharmacokinetics analysis demonstrated the nanoscale feature of micelles makes CPT to present longer retention time, resulting in a higher accumulation at tumor sites. Taken together, the disulfide core-cross-linked MeO-PEG2k-DHLA multifunctional micelles with high drug loading and excellent stability are potential candidates for tumor-targeting drug delivery.
Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Camptotecina/administração & dosagem , Portadores de Fármacos/química , Neoplasias/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacocinética , Camptotecina/farmacocinética , Reagentes de Ligações Cruzadas/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Glutationa/metabolismo , Células Hep G2 , Humanos , Células MCF-7 , Micelas , Nanopartículas/química , Neoplasias/patologia , Tamanho da Partícula , Polietilenoglicóis , Ácido Tióctico/análogos & derivadosRESUMO
7-Ethyl-10-hydroxycamptothecin (SN38), as a highly active topoisomerase I inhibitor, is 200-2000-fold more cytotoxic than irinotecan (CPT-11) commercially available as Camptosar®. However, poor solubility and low stability extensively restricted its clinical utility. In this report, dual SN38 phospholipid conjugate (Di-SN38-PC) prodrug based liposomes were developed in order to compact these drawbacks. Di-SN38-PC prodrug was first synthesized by inhomogeneous conjugation of two SN38-20-O-succinic acid molecules with L-α-glycerophosphorylcholine (GPC). The assembly of the prodrug was carried out without any excipient by using thin film method. Dynamic light scattering (DLS), transmission electron microscope (TEM) and cryogenic transmission electron microscopy (cyro-TEM) characterization indicated that Di-SN38-PC can form spherical liposomes with narrow particle size (<200nm) and negatively charged surface (-21.6±3.5mV). The loading efficiency of SN38 is 65.2 wt.% after a simple calculation. In vitro release test was further performed in detail. The results demonstrated that Di-SN38-PC liposomes were stable in neutral environment but degraded in a weakly acidic condition thereby released parent drug SN38 effectively. Cellular uptake studies reflected that the liposomes could be internalized into cells more significantly than SN38. In vitro antitumor activities were finally evaluated by MTT assay, colony formation assay, flow cytometry, RT-PCR analysis and Western Blot. The results showed that Di-SN38-PC liposomes had a comparable cytotoxicity with SN38 against MCF-7 and HBL-100, and a selective promotion of apoptosis of tumor cells. Furthermore, a pharmacokinetics test showed that Di-SN38-PC liposomes had a longer circulating time in blood compared with the parent drug. All the results indicate that Di-SN38-PC liposomes are an effective delivery system of SN38.
Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Camptotecina/análogos & derivados , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Camptotecina/administração & dosagem , Camptotecina/química , Camptotecina/farmacocinética , Camptotecina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lipossomos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Fosfolipídeos/administração & dosagem , Fosfolipídeos/química , Fosfolipídeos/farmacocinética , Fosfolipídeos/farmacologia , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacocinética , Solubilidade , Ácido Succínico/administração & dosagem , Ácido Succínico/química , Ácido Succínico/farmacocinética , Ácido Succínico/farmacologiaRESUMO
This paper constructs numerical models of bioprosthetic heart valve and blood. The fluid solid interaction is carried out using penalty function method. The mechanical property of the bioprosthetic heart valve during cardiac cycle is simulated with ANSYS software. Results show that the Von Mises stress concentrates at the junction of attachment edge and coaptation edge. The open time of bioprosthetic heart valve is consistent with that of actural measurement. The peak velocity of blood is in the range of physiology. This model provides more realistic mechanical property of bioprosthetic heart valve during cardiac cycle compared to pure solid model, and facilitates design and optimization of bioprosthetic heart valve.
Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Modelos Cardiovasculares , Valvas Cardíacas , Humanos , Desenho de PróteseRESUMO
Uric acid metabolism disorder triggers metabolic diseases, especially gout. However, increasing uric acid excretion remains a challenge. Here, an accelerative uric acid excretion pathway via an oral intestine-explosive hydrogel microsphere merely containing uricase and dopamine is reported. After oral administration, uricase is exposed and immobilized on intestinal mucosa along with an in situ dopamine polymerization via a cascade reaction triggered by the intestinal specific environment. By this means, trace amount of uricase is required to in situ up-regulate uric acid transporter proteins of intestinal epithelial cells, causing accelerated intestinal uric acid excretion. From in vitro data, the uric acid in fecal samples from gout patients could be significantly reduced by up to 37% by the mimic mucosa-immobilized uricase on the isolated porcine tissues. Both hyperuricemia and acute gouty arthritis in vivo mouse models confirm the uric acid excretion efficacy of intestine-explosive hydrogel microspheres. Fecal uric acid excretion is increased around 30% and blood uric acid is reduced more than 70%. In addition, 16S ribosomal RNA sequencing showed that the microspheres optimized intestinal flora composition as well. In conclusion, a unique pathway via the intestine in situ regulation to realize an efficient uric acid intestinal excretion for gout therapy is developed.
Assuntos
Gota , Ácido Úrico , Humanos , Camundongos , Suínos , Animais , Ácido Úrico/metabolismo , Microesferas , Dopamina , Urato Oxidase , Hidrogéis , Gota/tratamento farmacológico , Gota/genética , IntestinosRESUMO
INTRODUCTION: Chronic inflammation is the major pathological feature of Atherosclerosis(As). Inflammation may accelerate plaque to develop, which is a key factor resulting in the thinning of the fibrous cap and the vulnerable rupture of plaque. Presently, clinical treatments are still lacking. It is necessary to find a safe and effective treatment for As inflammation. Simiaoyongan Decoction (SMYA) has potential anti-inflammatory and plaque protection effects. This protocol aims to evaluate the efficacy, safety, and mechanism of SMYA for patients with carotid atherosclerotic plaque. METHODS/DESIGN: The assessment of SMYA clinical trial is designed as a randomized, double-blind, placebo-controlled study. The sample size is 86 cases in total, with 43 participants in the intervention group and the control group respectively. The intervention group takes SMYA, while the control group takes SMYA placebo. The medication lasts for 14 days every 10 weeks, with a total of 50 weeks. We will use carotid artery high resolution magnetic resonance imaging (HR-MRI) to measure plaque. The plaque minimum fiber cap thickness (PMFCT) is adopted as the primary outcome. The secondary outcomes include plaque fiber cap volume, volume percentage of fiber cap, lipid-rich necrotic core (LRNC) volume, volume percentage of LRNC, internal bleeding volume of plaque, internal bleeding volume percentage of plaque, plaque calcification volume, volume percentage of plaque calcification, lumen stenosis rate, average and a maximum of vessel wall thickness, vessel wall volume, total vessel wall load, carotid atherosclerosis score, hs-CRP, IL-1ß and IL-6, the level of lipid profiles and blood glucose, blood pressure, and body weight. DISCUSSION: We anticipate that patients with As plaque will be improved from SMYA by inhibiting inflammation to enhance plaque stability. This study analyzes plaque by using HR-MRI to evaluate the clinical efficacy and safety of SMYA. Moreover, we conduct transcriptome analysis, proteomic analysis, and metagenomic analysis of blood and stool of participants to study the mechanism of SMYA against As plaque. This is the first prospective TCM trial to observe and treat As plaque by inhibiting inflammatory reaction directly. If successful, the finding will be valuable in the treatment of As plaque and drug development, especially in the "statin era". TRIAL REGISTRATION NUMBER: This trial is registered on Chinese Clinical Trials.gov with number ChiCTR2000039062 on October 15, 2020 ( http://www.chictr.org.cn ).