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1.
Langmuir ; 40(20): 10589-10599, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38728854

RESUMO

Optically transparent glass with antifogging and antibacterial properties is in high demand for endoscopes, goggles, and medical display equipment. However, many of the previously reported coatings have limitations in terms of long-term antifogging and efficient antibacterial properties, environmental friendliness, and versatility. In this study, inspired by catfish and sphagnum moss, a novel photoelectronic synergy antifogging and antibacterial coating was prepared by cross-linking polyethylenimine-modified titanium dioxide (PEI-TiO2), polyvinylpyrrolidone (PVP), and poly(acrylic acid) (PAA). The as-prepared coating could remain fog-free under hot steam for more than 40 min. The experimental results indicate that the long-term antifogging properties are due to the water absorption and spreading characteristics. Moreover, the organic-inorganic hybrid of PEI and TiO2 was first applied to enhance the antibacterial performance. The Staphylococcus aureus and the Escherichia coli growth inhibition rates of the as-prepared coating reached 97 and 96% respectively. A photoelectronic synergy antifogging and antibacterial mechanism based on the positive electrical and photocatalytic properties of PEI-TiO2 was proposed. This investigation provides insight into designing multifunctional bioinspired surface materials to realize antifogging and antibacterial that can be applied to medicine and daily lives.


Assuntos
Antibacterianos , Escherichia coli , Staphylococcus aureus , Titânio , Antibacterianos/farmacologia , Antibacterianos/química , Titânio/química , Titânio/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Polietilenoimina/química , Polietilenoimina/farmacologia , Resinas Acrílicas/química , Resinas Acrílicas/farmacologia , Testes de Sensibilidade Microbiana , Povidona/química , Propriedades de Superfície
2.
Mol Pharm ; 15(7): 2857-2869, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29763559

RESUMO

Glucagon-like peptide 1 (GLP-1) has recently received significant attention as an efficacious way to treat diabetes mellitus. However, the short half-life of the peptide limits its clinical application in diabetes. In our previous study, a novel GLP-1 analog (PGLP-1) with a longer half-life was synthesized and evaluated. Herein, we prepared the PGLP-1-loaded poly(d,l-lactide- co-glycolide) microspheres to achieve long-term effects on blood glucose control. The incorporation of zinc ion into the formulation can effectively decrease the initial burst release, and a uniform drug distribution was obtained, in contrast to native PGLP-1 encapsulated microspheres. We demonstrated that the solubility of the drug encapsulated in microspheres played an important role in in vitro release behavior and drug distribution inside the microspheres. The Zn-PGLP-1 microspheres had a prominent acute glucose reduction effect in the healthy mice. A hypoglycemic effect was observed in the streptozotocin (STZ) induced diabetic mice through a 6-week treatment of Zn-PGLP-1-loaded microspheres. Meanwhile, the administration of Zn-PGLP-1 microspheres led to the ß-cell protection and stimulation of insulin secretion. The novel GLP-1 analog-loaded sustained microspheres may greatly improve patient compliance along with a desirable safety feature.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/química , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Hipoglicemiantes/administração & dosagem , Animais , Preparações de Ação Retardada/administração & dosagem , Diabetes Mellitus Experimental/induzido quimicamente , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/farmacocinética , Humanos , Concentração de Íons de Hidrogênio , Hipoglicemiantes/farmacocinética , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Adesão à Medicação , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Estreptozocina/toxicidade , Acetato de Zinco/química
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2178-82, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-30035973

RESUMO

In order to reveal the mechanism of LLLI accelerating teeth moving, we investigated the changes of alkaline phosphatase and intracellular calcium concentration when osteoblasts under stress were subjected low-level-laser-irradiation (LLLI). MG-63 cells were divided into four groups: control group, stress group, LLLI group and LLLI-stress group. Osteoblasts were subjected to the mechanical stress by a four-point bending system at 0.5 Hz and 3 000 µstrain. The secretions of ALP of each group are measured by spectrophotometer. In the second part, MG-63 cells were divided into two groups: stress group and LLLI-stress group. We checked intracellular calcium concentration via FCM and fluorescent indicator fluo-3/AM at 0, 5, 15, 30 and 60 min under stress. LLLI- stress group will receive LLLI for 1 min after stress. Compared to a control group, increased ALP secretions were observed in the other three groups. But ALP secretions in LLLI-stress group were lower than stress group and LLLI group. THE changing curve of intracellular calcium concentration in laser-stress groups is gentle instead of "jumping" in stress group. Proper stress, LLLI and combined application of these two can increase the secretions of ALP in osteoblasts compared to the control group. But the secretions of ALP decreased when combined application of stress and LLLI compared to using alone. LLLI can regulate the changing rhythm of concentration of the intracellular calcium to promote proliferation of MG-63 cell under stress, which means LLLI can reduce the bone-formation of osteoblasts under stress.


Assuntos
Osteoblastos , Estresse Mecânico , Fosfatase Alcalina , Cálcio , Proliferação de Células , Citoplasma
4.
Histopathology ; 64(3): 336-47, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24387671

RESUMO

AIMS: Calcification in adamantinomatous craniopharyngioma (ACP) is troublesome for surgical intervention. The aim of this study was to examine the osteogenic proteins that play important roles in the calcium deposition of the odontogenic/osteogenic tissues in craniopharyngioma. METHODS AND RESULTS: Craniopharyngiomas (n = 89) were investigated for the presence and expression pattern of the osteoinductive/odontoinductive factor bone morphogenetic protein-2 (Bmp2) and two osteoblastic differentiation makers, Runt-related transcription factor-2 (Runx2) and Osterix, using immunohistochemistry and Western blotting. Our results showed that Bmp2, Runx2 and Osterix levels increased in cases with high calcification and correlated positively with the degree of calcification in ACP, whereas they showed little or no expression in squamous papillary craniopharyngioma. In ACP, Bmp2 was expressed primarily in the stellate reticulum and whorl-like array cells; Runx2 and Osterix tended to be expressed in calcification-related epithelia, including whorl-like array cells and epithelia in/around wet keratin and calcification lesions. CONCLUSIONS: Our study indicated, for the first time, that osteogenic factor Bmp2 may play an important role in the calcification of ACP via autocrine or paracrine mechanisms. Given the presence of osteogenic markers (Runx2 and Osterix), craniopharyngioma cells could differentiate into an osteoblast-like lineage, and the process of craniopharyngioma calcification resembles that which occurs in osteogenesis/odontogenesis.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Calcinose/metabolismo , Calcinose/patologia , Cálcio/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Craniofaringioma/metabolismo , Craniofaringioma/patologia , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Fatores de Transcrição/metabolismo , Adolescente , Adulto , Idoso , Western Blotting , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Odontogênese , Osteogênese , Fator de Transcrição Sp7 , Adulto Jovem
5.
Quant Imaging Med Surg ; 14(1): 136-143, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38223122

RESUMO

Background: Early childhood bone development affects that of bone disease in adolescence and adulthood. Many diseases can affect the cancellous bone or bone marrow. Therefore, it is of great significance to quantify the bone development of healthy children. The evaluation methods of bone development include bone age (BA) assessment and dual-energy X-ray bone mineral densitometry (DXA), both of which have strong subjectivity. The present study was conducted to improve our understanding of the bone development of healthy children using the quantitative parameters derived from iterative decomposition of water and fat with echo asymmetry and least squares estimation quantification (IDEAL-IQ) sequence. Methods: Our study enrolled healthy children between January 2022 to December 2022 consecutively in Children's Hospital of Shanxi. The inclusion criteria were as follows: (I) age ≤18 years; (II) no contraindications (surgical and interventional devices for ferromagnetic materials, cardiac implantable electronic devices, cochlear implants, insulin pumps, dental implants containing metal or alloy) to magnetic resonance imaging (MRI) scan. The exclusion criteria were as follows: (I) previous malignant disease, (II) previous chemoradiotherapy, (III) previous spine surgery, (IV) previous or acute vertebral compression fracture, (V) artifacts present in images. Participants underwent MRI scans using IDEAL-IQ sequence in the lumbar vertebrae. The IDEAL-IQ parameters [proton density fat fraction (PDFF), 1/T2* (R2*)] were obtained. The factor analysis of variance was applied to compare the differences of PDFF and R2* in different lumbar vertebral groups. The Kruskal-Wallis H test or Mann-Whitney U test was applied to compare the differences of quantitative data among different gender or age groups. Spearman correlation analysis was applied to study the relationship among the age, PDFF, and R2*. Results: A total of 145 participants (76 males, 69 females) were evaluated. There were no significant differences in PDFF and R2* of different lumbar vertebrae (PPDFF=0.338, PR2*=0.868). The average age was 36 [13-72] months. They were assigned into 4 groups (0-11, 12-35, 36-71, and 72-144 months). As the age increased, the average PDFF and R2* both increased significantly (rPDFF=0.659, rR2*=0.359, P<0.001). There were significant statistical differences in PDFF and R2* between the 4 age groups (ZPDFF=46.651, ZR2*=27.537, P<0.001). Moreover, the PDFF was also positively correlated with R2* (r=0.576, P<0.001). No association was found between the gender and PDFF, R2* (PPDFF=0.949, PR2*=0.177). Conclusions: The quantitative parameters derived from IDEAL-IQ in the lumbar vertebrae of healthy children will improve our understanding of bone development and provide a basis for further exploring the diseases that affect children's bone development.

6.
Front Mol Neurosci ; 15: 1081097, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36683851

RESUMO

The KCNK4 gene, predominantly distributed in neurons, plays an essential role in controlling the resting membrane potential and regulating cellular excitability. Previously, only two variants were identified to be associated with human disease, facial dysmorphism, hypertrichosis, epilepsy, intellectual/developmental delay, and gingival overgrowth (FHEIG) syndrome. In this study, we performed trio-based whole exon sequencing (WES) in a cohort of patients with epilepsy. Two de novo likely pathogenic variants were identified in two unrelated cases with heterogeneous phenotypes, including one with Rolandic epilepsy and one with the FHEIG syndrome. The two variants were predicted to be damaged by the majority of in silico algorithms. These variants showed no allele frequencies in controls and presented statistically higher frequencies in the case cohort than that in controls. The FHEIG syndrome-related variants were all located in the region with vital functions in stabilizing the conductive conformation, while the Rolandic epilepsy-related variant was distributed in the area with less impact on the conductive conformation. This study expanded the genetic and phenotypic spectrum of KCNK4. Phenotypic variations of KCNK4 are potentially associated with the molecular sub-regional effects. Carbamazepine/oxcarbazepine and valproate may be effective antiepileptic drugs for patients with KCNK4 variants.

7.
J Med Virol ; 83(4): 616-21, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21328375

RESUMO

The objectives of the study were to estimate the prevalence of anti-hepatitis C virus (HCV) positivity among blood donors from Chengdu, China, and to determine risk factors associated with infection. In this study, data were collected from volunteer blood donors between July 2006 and June 2007. Anti-HCV test was performed in 119,518 donors. To identify risk factors associated with HCV infections a case-control study was conducted in 305 unique HCV-seropositive blood donors and 610 seronegative donors matched for age and sex. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression. The population attributable risk (PAR) to risk factor was estimated according to the Bruzzi's formula. The prevalence of anti-HCV positivity was 0.53% (95% CI: 0.489-0.572%). The final multivariate model included the following independent HCV risk factors: razor sharing (OR=29.16; 95% CI: 12.89-66.00), blood transfusion (OR=20.84; 95% CI: 3.76-115.45), acupuncture (OR=8.01; 95% CI: 3.16-20.30), a history of hospitalization, injections >10 years earlier, a family history of hepatitis B, dental treatment, and ear piercing. The PAR of risk factors are 68.4%, 6.3%, 14.1%, 23.1%, 29.5%, 29.3%, 38.9%, and 27.8%, respectively, and the total PAR is 98.3%. Infection with HCV among blood donors in Chengdu is associated with iatrogenic risk factors and beauty treatment-related risk. Razor sharing is an important risk factor for HCV infection. These results indicate that infection control measures in healthcare settings may reduce the burden of HCV infection and there is a need for development of effective educational programs to improve HCV knowledge among beauty culture professionals, barber cosmetologists, and the general public to avoid risk behaviors.


Assuntos
Doadores de Sangue , Anticorpos Anti-Hepatite C/sangue , Hepatite C/epidemiologia , Hepatite C/virologia , Adolescente , Adulto , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Soroepidemiológicos , Adulto Jovem
8.
Biomed Mater ; 16(6)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34571498

RESUMO

Oral insulin has been regarded as the best alternative to insulin injection in therapy of diabetes because of its convenience and painlessness. However, several obstacles in the gastrointestinal tract, such as gastric acid and enzyme, greatly reduce the bioavailability of oral insulin. Herein, we report design and preparation of poly (d, l-lactic-co-glycolic acid) nanoparticles (PLGA NPs) coated with 5ß-cholanic acid modified glycol chitosan (GC-CA) (GC-CA@PLGA NPs) to improve the oral delivery of insulin. The GC-CA@PLGA NPs with the size of (302.73 ± 5.13 nm) and zeta potential of (25.03 ± 0.31 mV) were synthesized using the double-emulsion method. The insulin-loading capacity and encapsulation efficiency were determined to be 5.77 ± 0.58% and 51.99 ± 5.27%, respectively. Compared with GC-modified PLGA NPs (GC@PLGA NPs) and bare PLGA NPs, the GC-CA@PLGA NPs showed excellent stability and uptake by Caco-2 cells after simulated gastric acid digestion. Further experiment suggests good biocompatibility of GC-CA@PLGA NPs, including hemolysis and cytotoxicity. Inin vivoexperiment, the insulin loaded in the GC-CA@PLGA NPs exhibited a long-term and stable release profile for lowering blood glucose and presented 30.43% bioavailability in oral administration. In brief, we have developed an efficient and safe drug delivery system, GC-CA@PLGA NPs, for significantly improved oral administration of insulin, which may find potential application in the treatment of diabetes.


Assuntos
Quitosana , Nanopartículas , Células CACO-2 , Ácidos Cólicos , Portadores de Fármacos , Humanos , Insulina , Tamanho da Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
9.
J Pharm Sci ; 110(3): 1182-1188, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33065128

RESUMO

This study evaluated the impact of poly(lactic-co-glycolic acid) (PLGA) microsphere formulations on in vitro release and in vivo plasma exposure of HsTX1[R14A], a potent inhibitor of the voltage-gated potassium channel Kv1.3, with potential to treat autoimmune conditions. Microspheres containing HsTX1[R14A] were prepared using different PLGA materials, including Resomer® RG502H, RG503H and PURASORB® PDLG 5004 (Purac). After assessing encapsulation efficiency and in vitro release, plasma concentrations of HsTX1[R14A] were quantified by LCMS/MS following subcutaneous administration of HsTX1[R14A]-loaded RG503H microspheres (15 mg/kg) or HsTX1[R14A] solution (4 mg/kg) to Sprague-Dawley rats. Microspheres prepared with Purac exhibited the greatest encapsulation efficiency (45.5 ± 2.4% (mean ± SD)) and RG502H the lowest (22.0 ± 6.4%). Release of HsTX1[R14A] was fastest in vitro for RG502H microspheres (maximum release at 31 days) and slowest for Purac (82 days). With a relatively rapid burst release of 20.0 ± 0.4% and a controlled release profile of up to 41 days, HsTX1[R14A]-loaded RG503H microspheres were selected for subcutaneous administration, resulting in detectable plasma concentrations for 11 days relative to 8 h following subcutaneous administration of HsTX1[R14A] solution. Therefore, subcutaneous administration of RG503H PLGA microspheres is a promising approach to be exploited for delivery of this immune modulator.


Assuntos
Glicóis , Peptídeos , Animais , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Sprague-Dawley
10.
J Manipulative Physiol Ther ; 33(2): 125-31, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20170778

RESUMO

OBJECTIVE: The purpose of this study was to investigate and measure the variable morphologies of axis vertebrae and explore the clinical significance of variations as it may pertain to clinical palpation and diagnostic imaging. METHODS: The common variable morphologies in 100 specimens of intact dry adult axis vertebrae (Chinese) were investigated and measured. The frequencies in deviation of odontoid processes, deviation of spinous processes, and presence of bifid spinous processes were observed. The distances between the apices of transverse processes and inferior articular facets were also measured. RESULTS: Variable morphologies of C2 that we observed were deviation of odontoid processes (14 cases, 14.0%), deviation of spinous processes (3 cases, 3.0%), and bifid spinous processes (95 cases, 95.0%). Of the bifid spinous processes, 56 had a process on the left side equal to the right side, 21 were longer on the left, and 18 were longer on the right. The distances between apices of transverse processes and inferior articular facets in the left side of C2 were 17.67 +/- 2.47 mm, and that of the right side were 17.81 +/- 2.55 mm. CONCLUSIONS: Because variable morphology of the axis is common, congenital deviation of the odontoid process, deviation of the spinous process, and asymmetrical bifid spinous processes should be taken into account during clinical palpation and diagnostic imaging.


Assuntos
Vértebra Cervical Áxis/anatomia & histologia , Adulto , Povo Asiático , Diagnóstico por Imagem , Humanos , Técnicas In Vitro , Processo Odontoide/anormalidades , Processo Odontoide/anatomia & histologia , Processo Odontoide/patologia , Palpação , Fotografação
11.
Acta Biomater ; 106: 428-438, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32044459

RESUMO

Biodegradable magnesium alloys are promising candidates for use in biomedical applications. However, degradable particles (DPs) derived from Mg-based alloys have been observed in tissue in proximity to sites of implantation, which might result in unexpected effects. Although previous in vitro studies have found that macrophages can take up DPs, little is known about the potential phagocytic pathway and the mechanism that processes DPs in cells. Additionally, it is necessary to estimate the potential bioeffects of DPs on macrophages. Thus, in this study, DPs were generated from a Mg-2.1Nd-0.2Zn-0.5Zr alloy (JDBM) by an electrochemical method, and then macrophages were incubated with the DPs to reveal the potential impact. The results showed that the cell viability of macrophages decreased in a concentration-dependent manner in the presence of DPs due to effects of an apoptotic pathway. However, the DPs were phagocytosed into the cytoplasm of macrophages and further degraded in phagolysosomes, which comprised lysosomes and phagosomes, by heterophagy instead of autophagy. Furthermore, several pro-inflammatory cytokines in macrophages were upregulated by DPs through the induction of reactive oxygen species (ROS) production. To the best of our knowledge, this is the first study to show that DPs derived from a Mg-based alloy are consistently degraded in phagolysosomes after phagocytosis by macrophages via heterophagy, which results in an inflammatory response owing to ROS overproduction. Thus, our research has increased the knowledge of the metabolism of biodegradable Mg metal, which will contribute to an understanding of the health effects of biodegradable magnesium metal implants used for tissue repair. STATEMENT OF SIGNIFICANCE: Biomedical degradable Mg-based alloys have great promise in applied medicine. Although previous studies have found that macrophages can uptake degradable particles (DPs) in vitro and observed in the sites of implantation in vivoin vivo, few studies have been carried out on the potential bioeffects relationship between DPs and macrophages. In this study, we analyzed the bioeffects of DPs derived from a Mg-based alloy on the macrophages. We illustrated that the DPs were size-dependently engulfed by macrophages via heterophagy and further degraded in the phagolysosome rather than autophagosome. Furthermore, DPs were able to induce a slight inflammatory response in macrophages by inducing ROS production. Thus, our research enhances the knowledge of the interaction between DPs of Mg-based alloy and cells, and offers a new perspective regarding the use of biodegradable alloys.


Assuntos
Implantes Absorvíveis , Ligas/metabolismo , Macrófagos/metabolismo , Ligas/química , Ligas/toxicidade , Humanos , Macrófagos/efeitos dos fármacos , Magnésio/química , Magnésio/metabolismo , Magnésio/toxicidade , Neodímio/química , Neodímio/metabolismo , Neodímio/toxicidade , Fagocitose/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Células THP-1 , Zinco/química , Zinco/metabolismo , Zinco/toxicidade , Zircônio/química , Zircônio/metabolismo , Zircônio/toxicidade
12.
Int J Biol Macromol ; 134: 1002-1012, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31063785

RESUMO

The combination of controlled release technology and targeted drug delivery has become a promising strategy for cancer therapy. In this study, cell-nanoparticle hybrid vector was constructed using mesenchymal stem cells as the targeting cellular carrier and biotinylated chitosan polymer nanoparticles as the drug depot. Drug-loaded nanoparticles (hydrodynamic size =377.0 ±â€¯14.6 nm and zeta potential = 9.6 ±â€¯1.9 mV) were prepared by encapsulating hydrophobic model drug curcumin into biotinylated chitosan polymer. The biotin-modified nanoparticles were anchored on biotinylated mesenchymal stem cells surface by biotin-avidin binding, achieving an upload of 54.73 ±â€¯3.95 pg/cell. The anchorage of nanoparticles on mesenchymal stem cells had no effect on their viability and homing property. Biotin-avidin binding lasted over 48 h, which could be sufficient for cell-directed tumor-tropic delivery. The in vitro and in vivo anti-tumor results advocate that cell-nanoparticle hybrid vector could prove beneficial in pulmonary melanoma metastasis therapy.


Assuntos
Quitosana , Curcumina/administração & dosagem , Portadores de Fármacos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Nanopartículas , Animais , Biotina , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Curcumina/química , Modelos Animais de Doenças , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Imunofluorescência , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Nanopartículas/química , Nanopartículas/ultraestrutura , Neoplasias/terapia , Polímeros , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Inflammation ; 42(2): 658-671, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30484006

RESUMO

Polydopamine (PDA) has a promising application as coating of biomaterials due to its favorable degradability and bioadaptability. However, its bioactivity, such as anti-inflammatory capacity, was still little known. Herein, we investigated whether degradable products of PDA could affect inflammatory response in lipopolysaccharide (LPS)-stimulated human THP-1-derived macrophages. The supernatants containing degradation products of PDA, annotated as PDA extracts, were collected after PDA being immersed in cell culture medium for 3 days. Wherein, the composition of the degradation products was analyzed by HPLC assay. Collected PDA extracts were diluted into 100%, 50%, and 25% of original concentration, respectively, to evaluate their anti-inflammatory ability on LPS-induced macrophages from the expression levels of pro-inflammatory cytokines to associated molecular mechanism. Our results showed that the PDA extracts were mainly composed of dopamine, quinine, and PDA segments. Furthermore, macrophages showed no cytotoxicity after PDA extract treatment with or without LPS, while the release levels of TNF-α and IL-6 by LPS-induced macrophages were decreased in dose-dependent by PDA extract treatment. Additionally, TLR-4 and MYD88 expression in protein and RNA level were downregulated by PDA extracts in LPS-induced macrophages. Similarly, PDA extracts effectively inhibited LPS-induced NF-κB trans-locating into nuclear by inactivation of the phosphorylation of IKK-α/ß and IKß-α. Of note, the production of LPS-induced ROS was reduced by PDA extracts in macrophages, while HO-1 expression, a critical protein of antioxidant signaling pathway, was increased. Based on these results, we proposed a potential mechanism by which degradation products of PDA suppressed inflammation of macrophages via downregulation TLR-4-MYD88-NFκB pathway and simultaneous activation HO-1 pathway, which might be a possible therapeutic target.


Assuntos
Meios de Cultura/química , Indóis/química , Inflamação/prevenção & controle , Macrófagos/citologia , Polímeros/química , Transdução de Sinais/efeitos dos fármacos , Antioxidantes/farmacologia , Técnicas de Cultura de Células , Regulação para Baixo/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Humanos , Indóis/farmacologia , Lipopolissacarídeos/efeitos adversos , Fator 88 de Diferenciação Mieloide/metabolismo , Polímeros/farmacologia , Células THP-1 , Receptor 4 Toll-Like/metabolismo
14.
Biomaterials ; 221: 119414, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31419654

RESUMO

The performance of biodegradable magnesium alloy stents (BMgS) requires special attention to non-uniform residual stress distribution and stress concentration, which can accelerate localized degradation after implantation. We now report on a novel concept in stent shape optimization using a finite element method (FEM) toolkit. A Mg-Nd-Zn-Zr alloy with uniform degradation behavior served as the basis of our BMgS. Comprehensive in vitro evaluations drove stent optimization, based on observed crimping and balloon inflation performance, measurement of radial strength, and stress condition validation via microarea-XRD. Moreover, a Rapamycin-eluting polymer coating was sprayed on the prototypical BMgS to improve the corrosion resistance and release anti-hyperplasia drugs. In vivo evaluation of the optimized coated BMgS was conducted in the iliac artery of New Zealand white rabbit with quantitative coronary angiography (QCA), optical coherence tomography (OCT) and micro-CT observation at 1, 3, 5-month follow-ups. Neither thrombus or early restenosis was observed, and the coated BMgS supported the vessel effectively prior to degradation and allowed for arterial healing thereafter. The proposed shape optimization framework based on FEM provides an novel concept in stent design and in-depth understanding of how deformation history affects the biomechanical performance of BMgS. Computational analysis tools can indeed promote the development of biodegradable magnesium stents.


Assuntos
Magnésio/química , Sirolimo/química , Ligas/química , Animais , Angiografia Coronária , Análise de Elementos Finitos , Polímeros/química , Coelhos , Tomografia de Coerência Óptica , Microtomografia por Raio-X
15.
Front Immunol ; 10: 2798, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849975

RESUMO

Mg-based alloys might be ideal biomaterials in clinical applications owing to favorable mechanical properties, biodegradability, biocompatibility, and especially their anti-inflammatory properties. However, the precise signaling mechanism underlying the inhibition of inflammation by Mg-based alloys has not been elucidated. Here, we investigated the effects of a Mg-2.1Nd-0.2Zn-0.5Zr alloy (denoted as JDBM) on lipopolysaccharide (LPS)-induced macrophages. THP-1 cell-derived macrophages were cultured on JDBM, Ti-6Al-4V alloy (Ti), 15% extract of JDBM, and 7.5 mM of MgCl2 for 1 h before the addition of LPS for an indicated time; the experiments included negative and positive controls. Our results showed JDBM, extract, and MgCl2 could decrease LPS-induced tumor necrosis factor (TNF) and interleukin (IL)-6 expression. However, there were no morphologic changes in macrophages on Ti or JDBM. Mechanically, extract and MgCl2 downregulated the expression of toll-like receptor (TLR)-4 and MYD88 compared with the positive control and inhibited LPS-induced nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways by inactivation of the phosphorylation of IKK-α/ß, IKß-α, P65, P38, and JNK. Additionally, the LPS-induced reactive oxygen species (ROS) expression was also decreased by extract and MgCl2. Interestingly, the expression of LPS-induced TNF and IL-6 could be recovered by knocking down TRPM7 of macrophages, in the presence of extract or MgCl2. Mechanically, the activities of AKT and AKT1 were increased by extract or MgCl2 with LPS and were blocked by a PI3K inhibitor, whereas siRNA TRPM7 inhibited only AKT1. Together, our results demonstrated the degradation products of Mg-based alloy, especially magnesium, and resolved inflammation by activation of the TRPM7-PI3K-AKT1 signaling pathway, which may be a potential advantage or target to promote biodegradable Mg-based alloy applications.


Assuntos
Ligas , Anti-Inflamatórios/farmacologia , Macrófagos/efeitos dos fármacos , Magnésio , Humanos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Macrófagos/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células THP-1 , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(1): 66-69, 2019 Feb 01.
Artigo em Zh | MEDLINE | ID: mdl-30854822

RESUMO

OBJECTIVE: This study aimed to compare the porcelain-fused-to-metal (PFM) crown artifact in the magnetic resonance imaging (MRI) of the two magnetic resonance deartifact techniques in studying the application value of the propeller-fast spin-echo T2-weighted sequence (FSE T2WI) in troubleshooting PFM crown artifacts. METHODS: A total of 48 patients with right mandible first molar crown who underwent MRI head examination were chosen as subjects in the study. According to different metal substrates, PFM crowns were divided to three types, namely, nickel-chromium alloy crown, cobalt-chromium alloy crown and titanium crown. The patients received two MRI scan sequences, that is, FSE T2WI and propeller-FSE T2WI sequences. The MRI artifacts areas in two sequences were measured. RESULTS: The difference between FSE T2WI and propeller-FSE T2WI sequences in three kinds of PFM crown was significant (P<0.05). CONCLUSIONS: Propeller-FSE T2WI sequence technique can effectively reduce the metal artifacts of various PFM crowns.


Assuntos
Coroas , Porcelana Dentária , Imageamento por Ressonância Magnética , Artefatos , Humanos , Espectroscopia de Ressonância Magnética
17.
J Biosci Bioeng ; 105(1): 65-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18295723

RESUMO

In this study, the cytotoxicity and transfection efficiency of using chitosan/DNA complex combined with poly(ethylenimine) (PEI) were investigated. The combination of PEI with the chitosan/DNA complex markedly enhanced the gene expression of HeLa cells to 1000-fold of that induced by chitosan alone. PEI's cytotoxicity was considerably decreased upon combination with the chitosan/DNA complex. Furthermore, the PEI/chitosan/DNA could maintain the gene expression efficiency in the presence of serum.


Assuntos
Quitosana/química , Polietilenoimina/química , Transfecção/métodos , DNA/química , Humanos
18.
PLoS One ; 13(3): e0193276, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29538391

RESUMO

Biodegradable Mg-based alloys have shown great potential as bone fixation devices or vascular stents. As implant biomaterials, the foreign body reaction (FBR) is an important issue to be studied, where the inflammatory cells play a key role. Here, we used two inflammatory cell lines i.e. THP-1 cells and THP-1 macrophages, to evaluate the effect of Mg-Nd-Zn-Zr alloy (denoted as JDBM) extracts on cell viability, death modes, cell cycle, phagocytosis, differentiation, migration and inflammatory response. The results showed that high-concentration extract induced necrosis and complete damage of cell function. For middle-concentration extract, cell apoptosis and partially impaired cell function were observed. TNF-α expression of macrophages was up-regulated by co-culture with extract in 20% concentration, but was down-regulated in the same concentration in the presence of LPS stimulation. Interestingly, the production of TNF-α decreased when macrophages were cultured in middle and high concentration extracts independent of LPS. Cell viability was also negatively affected by magnesium ions in JDBM extracts, which was a potential factor affecting cell function. Our results provide new information about the impact of Mg alloy extracts on phenotype of immune cells and the potential mechanism, which should be taken into account prior to clinical applications.


Assuntos
Ligas/farmacologia , Apoptose/efeitos dos fármacos , Implantes Absorvíveis , Ligas/química , Ligas/metabolismo , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Fagocitose/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos
19.
Chem Commun (Camb) ; 54(63): 8737-8740, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30027958

RESUMO

We report a novel and easy-to-fabricate polynuclear nanoparticle based on the collaborative re-assembly of nanoparticles as a robust chemogene co-delivery platform. Specifically, the polynuclear nanoparticle carrying DOX and siBcl-2 exerts remarkable co-delivery efficiency, increases tumour cell apoptosis and inhibits tumour cell proliferation in vitro and in vivo.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Nanopartículas/química , Polímeros/química , RNA Interferente Pequeno/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Tamanho da Partícula , RNA Interferente Pequeno/química , Relação Estrutura-Atividade , Propriedades de Superfície
20.
Int J Pharm ; 343(1-2): 255-61, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17624698

RESUMO

Gene therapy provides great opportunities for treating diseases from genetic disorders, infections and cancer. The development of efficient and safe gene transfer systems could be one of the most important factors for successful gene therapy. In the present study, an amphiphilic compound, polyethylenimine (PEI, MW 800)-cholesterol (PEI 800-Chol), firstly designed to modify the surface of liposomes, was synthesized. Polycation liposomes (PCLs) composed of soybean phospholipids (SPL), cholesterol (Chol) and PEI 800-Chol were prepared using film hydration method. The mean particle size of the PCLs was 133.0 nm and the zeta potential was 50.1+/-2.6 mV. Due to the PEI anchored onto the surface of liposomes, higher buffering capacity of PCLs was observed, indicating the potential for buffering in the acidic pH environment of the endosomes. Compared to Lipofectamine 2000, PCLs have equivalent transfection efficiency with significantly low cytotoxicity. Interestingly, the transfection activity of PCLs was not influenced in the presence of serum. Furthermore, we constructed another PCL composed of PEI 800-Chol and DOPE, and transfection efficiency increased notably. In conclusion, the PCLs described in this study have high transfection efficiency with low cytotoxicity, as well as the protection ability from serum, which suggests PCLs would be a potential non-viral gene delivery system.


Assuntos
Colesterol , Lipossomos , Polietilenoimina , Transfecção/métodos , Colesterol/administração & dosagem , Colesterol/química , Colesterol/toxicidade , DNA/administração & dosagem , Composição de Medicamentos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Lipossomos/química , Lipossomos/toxicidade , Plasmídeos , Polietilenoimina/administração & dosagem , Polietilenoimina/química , Polietilenoimina/toxicidade
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