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1.
Sci Rep ; 14(1): 2767, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38307957

RESUMO

Colorectal cancer (CRC) is one of the most prevalent and deadliest illnesses all around the world. Growing proofs demonstrate that tumor-associated macrophages (TAMs) are of critical importance in CRC pathogenesis, but their mechanisms remain yet unknown. The current research was designed to recognize underlying biomarkers associated with TAMs in CRC. We screened macrophage-related gene modules through WGCNA, selected hub genes utilizing the LASSO algorithm and COX regression, and established a model. External validation was performed by expression analysis using datasets GSE14333, GSE74602, and GSE87211. After validating the bioinformatics results using real-time quantitative reverse transcription PCR, we identified SPP1, C5AR1, MMP3, TIMP1, ADAM8 as potential biomarkers associated with macrophages in CRC.


Assuntos
Neoplasias Colorretais , Genes Reguladores , Humanos , Prognóstico , Macrófagos , Biomarcadores , Neoplasias Colorretais/genética , Biomarcadores Tumorais/genética , Proteínas de Membrana , Proteínas ADAM
2.
Biomed Mater ; 18(6)2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37852221

RESUMO

Development of tissue-engineeredin vitrohuman bone defect models for evaluation of bone repair materials (BRMs) is a promising approach for addressing both translational and ethical concerns regarding animal models. In this study, human bone marrow mesenchymal stem cell sheets were stacked to form a periosteum like tissue. HE staining showed a cell-dense, multilayered structure. BRMs were implanted in the defect area of the three-dimensional (3D) model. The CCK-8 test demonstrated that the 3D model was stronger in resisting the cytotoxicity of three kinds of commercial BRMs than the 2D culture model, which was consistent within vivoresults. After 28 d implantation in the 3D model, western blot and RT-qPCR showed that three materials induced increased expressions of RUNX2, OSX, OCN, OPN, while Materials B and C seemed to have stronger osteoinductivity than A.In vivoexperiments also confirmed the osteoinductivity of the BRMs after 28 and 182 d implantation. Alizarin red staining proved that the mineralized nodules of Materials B and C were more than that of A. The differences of osteogenic properties among three BMRs might be attributed to calcium ion release. This cell sheet-based bone tissue model can resist cytotoxicity of BRMs, demonstrating the priority of long-term evaluation of osteoinductivity of BRMs. Further, the osteoinduction results of the 3D model corresponded to that ofin vivoexperiments, suggesting this model may have a potential to be used as a novel tool for rapid, accurate evaluation of BRMs, and thus shorten their research and development process.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Animais , Humanos , Diferenciação Celular , Periósteo , Células Cultivadas , Células da Medula Óssea
3.
Artigo em Chinês | MEDLINE | ID: mdl-37551570

RESUMO

Objective:To explore the effect of fully automatic image segmentation of adenoid and nasopharyngeal airway by deep learning model based on U-Net network. Methods:From March 2021 to March 2022, 240 children underwent cone beam computed tomography(CBCT) in the Department of Otolaryngology, Head and Neck Surgery, General Hospital of Shenzhen University. 52 of them were selected for manual labeling of nasopharynx airway and adenoid, and then were trained and verified by the deep learning model. After applying the model to the remaining data, compare the differences between conventional two-dimensional indicators and deep learning three-dimensional indicators in 240 datasets. Results:For the 52 cases of modeling and training data sets, there was no significant difference between the prediction results of deep learning and the manual labeling results of doctors(P>0.05). The model evaluation index of nasopharyngeal airway volume: Mean Intersection over Union(MIOU) s (86.32±0.54)%; Dice Similarity Coefficient(DSC): (92.91±0.23)%; Accuracy: (95.92±0.25)%; Precision: (91.93±0.14)%; and the model evaluation index of Adenoid volume: MIOU: (86.28±0.61)%; DSC: (92.88±0.17)%; Accuracy: (95.90±0.29)%; Precision: (92.30±0.23)%. There was a positive correlation between the two-dimensional index A/N and the three-dimensional index AV/(AV+NAV) in 240 children of different age groups(P<0.05), and the correlation coefficient of 9-13 years old was 0.74. Conclusion:The deep learning model based on U-Net network has a good effect on the automatic image segmentation of adenoid and nasopharynx airway, and has high application value. The model has a certain generalization ability.


Assuntos
Tonsila Faríngea , Criança , Humanos , Adolescente , Tonsila Faríngea/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Faringe , Tomografia Computadorizada de Feixe Cônico , Nariz
4.
Artigo em Chinês | MEDLINE | ID: mdl-37551576

RESUMO

With the enhancement of aesthetic awareness of children's oral maxillofacial development, multi-disciplinary doctors pay attention to children's oral maxillofacial management. Artificial intelligence (AI) technology has been gradually applied to all fields of children's oral maxillofacial management because of its outstanding advantages in medical screening and auxiliary decision-making. This article reviews the application of AI technology in the screening, diagnosis, treatment and follow-up of oral maxillofacial management in children.


Assuntos
Inteligência Artificial , Criança , Humanos , Administração Oral
5.
Front Surg ; 10: 1083961, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36793309

RESUMO

Objective: This study aims to evaluate the effect of bilateral nasal packing on sleep oxygen saturation and its influencing factors on the first night after general anesthesia. Method: A total of 36 adult patients who underwent bilateral nasal packing with a nonabsorbable expanding sponge after general anesthesia surgery were prospectively studied. All these patients underwent overnight oximetry tests before and the first night after surgery. The following oximetry variables were collected for analysis: the lowest oxygen saturation (LSAT), the average oxygen saturation (ASAT), the oxygen desaturation index of ≥4% (ODI4), and the percentage of time with oxygen saturation below 90% (CT90). Results: Among the 36 patients, the incidences of both sleep hypoxemia and moderate-to-severe sleep hypoxemia increased with bilateral nasal packing after general anesthesia surgery. All the pulse oximetry variables we studied deteriorated significantly after surgery: both LSAT and ASAT decreased significantly (P < 0.05), while both ODI4 and CT90 increased significantly (P < 0.05). In a multiple logistic regression analysis, body mass index (BMI), LSAT, and modified Mallampati grade were found to be independently predictive for a larger decrease in LSAT (≥5%) after surgery (all P's < 0.05). Conclusion: Bilateral nasal packing after general anesthesia could induce or aggravate sleep hypoxemia, especially in patients with obesity, relatively normal sleep oxygen saturation, and high modified Mallampati grades.

6.
Int J Biol Macromol ; 230: 123158, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36610582

RESUMO

Local hemostats still face obstacles to efficiently achieving hemostasis and promoting wound healing. Herein, a series of multifunctional well-degradable hemostatic sponges based-on carboxymethylated yeast ß-glucan (CMYG) were fabricated by lyophilization. The porous CMYG sponge not only could absorb blood quickly (44.12 g/g), but also possessed unexpected tissue adhesion (∼30 kPa), and it represented good biocompatibility in vitro on fibroblasts and red blood cells. Notably, compared with the commercial Celox™, the CMYG sponge achieved more rapid hemostasis and significantly reduced blood loss in liver injury rat models by rapid wound block. Interestingly, the developed sponge showed an outstanding effect on antioxidant, anti-infection, anti-inflammatory, and cell proliferation, which are beneficial for further wound repair. Overall, these results suggest that the CMYG sponge is a promising candidate for the clinical management of uncontrollable hemorrhage and the further development of wound dressing materials throughout skin defect repair.


Assuntos
Hemostáticos , Saccharomyces cerevisiae , Ratos , Animais , Adesivos/farmacologia , Hemostasia , Hemostáticos/farmacologia , Hemorragia/tratamento farmacológico , Bandagens , Anti-Inflamatórios/farmacologia , Antibacterianos/farmacologia
7.
J Clin Sleep Med ; 19(2): 303-308, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36263860

RESUMO

STUDY OBJECTIVES: To investigate the feasibility and effectiveness of nasopharyngeal tube (NPT) insertion in alleviating sleep hypoxemia during the first night after velopharyngeal surgery in patients with obstructive sleep apnea syndrome (OSAS). METHODS: In this prospective nonblinded, randomized, controlled study, 46 patients with obstructive sleep apnea syndrome (OSAS) who underwent velopharyngeal surgery were enrolled and randomly allocated to the control group (with no NPT insertion) and the NPT insertion group. Both groups underwent overnight pulse oximetry tests during the first postoperative night. RESULTS: One patient in the NPT insertion group was excluded because of involuntary self-removal of NPT during sleep. A total of 45 patients with OSAS were included for analysis, with 23 in the control group and 22 in the NPT insertion group. No significant differences in preoperative baseline information were found between the two groups. Compared with the patients in the control group, those patients in the NPT insertion group showed a significantly higher value of the lowest oxygen saturation of oximetry during the first postoperative night (85.0 ± 4.0% vs 79.3 ± 8.0%) (P = .005). The percentage of patients with lowest oxygen saturation of oximetry < 80% in the NPT insertion group was only 9.1% (2 of 22), which was significantly lower than 39.1% (9 of 23) in the control group (P = .035). No patient reported unbearable discomfort related to NPT insertion. The most common mild discomfort was occasional pharyngeal foreign body sensation (6 of 22, 27.3%). CONCLUSIONS: NPT insertion could lessen the severity of sleep hypoxemia during the first night after velopharyngeal surgery in patients with OSAS and showed excellent compliance. This method could be a potential alternative option for decreasing the risks of complications related to severe sleep hypoxemia during the early postoperative days. CITATION: Zhang J, Guan S, Zhang C, Du X, Li T, Xiao S. Nasopharyngeal tube effects on alleviating sleep hypoxemia during the first night following velopharyngeal surgery in patients with obstructive sleep apnea syndrome. J Clin Sleep Med. 2023;19(2):303-308.


Assuntos
Nasofaringe , Apneia Obstrutiva do Sono , Humanos , Estudos Prospectivos , Nasofaringe/cirurgia , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/cirurgia , Hipóxia/terapia , Hipóxia/complicações , Oximetria , Sono
8.
Biotechnol Lett ; 45(1): 57-67, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36550337

RESUMO

OBJECTIVES: To develop a rapid and simple method to fabricate intact, robust cell sheets from common cell culture dishes by combination of a macromolecular crowding (MMC) reagent and vitamin C. RESULTS: It was found that 3T3 fibroblasts or human bone marrow mesenchymal stem cells (hBMSCs) and their secreted cell derived extracellular matrices could be easily detached as intact cell sheets under gently pipetting after treated by MMC and vitamin C for 4 days. This method also allowed fabrication of functional multi-layered hepatic cell sheets by culturing 10 × 104 cells/cm2 HepG2 cells on top of confluent 3T3 fibroblast layers. What's more, MMC induced hBMSC cell sheets demonstrated 1.9 times larger area and 1.6 times greater cell number than that of cell sheets harvested from temperature-responsive cell culture dishes. CONCLUSION: MMC based method make it possible to fabricate various types of cell sheets more conveniently, economically, and thus may facilitate wide application of cell sheet technology.


Assuntos
Técnicas de Cultura de Células , Células-Tronco Mesenquimais , Humanos , Fibroblastos , Matriz Extracelular , Células-Tronco Mesenquimais/fisiologia , Ácido Ascórbico , Engenharia Tecidual
9.
Int J Mol Sci ; 23(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36292932

RESUMO

In recent years, cyclic peptides have attracted much attention due to their chemical and enzymatic stability, low toxicity, and easy modification. In general, the self-assembled nanostructures of cyclic peptides tend to form nanotubes in a cyclic stacking manner through hydrogen bonding. However, studies exploring other assembly strategies are scarce. In this context, we proposed a new assembly strategy based on cyclic peptides with covalent self-assembly. Here, cyclic peptide-(DPDPDP) was rationally designed and used as a building block to construct new assemblies. With cyclo-(DP)3 as the structural unit and 2,2'-diamino-N-methyldiethylamine as the linker, positively charged nanospheres ((CP)6NS) based on cyclo-(DP)3 were successfully constructed by covalent self-assembly. We assessed their size and morphology by scanning electron microscopy (SEM), TEM, and DLS. (CP)6NS were found to have a strong positive charge, so they could bind to siRNA through electrostatic interactions. Confocal microscopy analysis and cell viability assays showed that (CP)6NS had high cellular internalization efficiency and low cytotoxicity. More importantly, real-time polymerase chain reaction (PCR) and flow cytometry analyses indicated that (CP)6NS-siRNA complexes potently inhibited gene expression and promoted tumor cell apoptosis. These results suggest that (CP)6NS may be a potential siRNA carrier for gene therapy.


Assuntos
Nanosferas , Nanoestruturas , Nanotubos , RNA Interferente Pequeno/farmacologia , Peptídeos Cíclicos/química , Nanosferas/química , Nanotubos/química , Nanoestruturas/química
10.
Biosci Trends ; 16(4): 257-266, 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-35965099

RESUMO

The evidence shows that there is an associated relationship between hepatosteatosis and insulin resistance. While some existing genetic induction animal and patient models challenge this relationship, indicating that hepatosteatosis is dissociated from insulin resistance. However, the molecular mechanisms of this dissociation remain poorly understood due to a lack of available, reliable, and simplistic setup models. Currently, we used primary rat hepatocytes (rHPCs), co-cultured with rat hepatic stellate cells (HSC-T6) or human foreskin fibroblast cells (HFF-1) in stimulation with high insulin and glucose, to develop a model of steatosis charactered as dissociated lipid accumulation from insulin resistance. Oil-Red staining significantly showed intracellular lipid accumulated in the developed model. Gene expression of sterol regulatory element-binding protein 1c (SREBP1c) and elongase of very-long-chain fatty acids 6 (ELOVL6), key genes responsible for lipogenesis, were detected and obviously increased in this model. Inversely, the insulin resistance related genes expression included phosphoenolpyruvate carboxykinase 1 (PCK1), pyruvate dehydrogenase lipoamide kinase isozyme 4 (PDK4), and glucose-6-phosphatase (G6pase) were decreased, suggesting a dissociation relationship between steatosis and insulin resistance in the developed model. As well, the drug metabolism of this developed model was investigated and showed up-regulation of cytochrome P450 3A (CYP3A) and down-regulation of cytochrome P450 2E1 (CYP2E1) and cytochrome P450 1A2 (CYP1A2). Taken together, those results demonstrate that the in vitro model of dissociated steatosis from insulin resistance was successfully created by our co-cultured cells in high insulin and glucose medium, which will be a potential model for investigating the mechanism of insulin resistance dissociated steatosis, and discovering a novel drug for its treatment.


Assuntos
Fígado Gorduroso , Resistência à Insulina , Insulinas , Animais , Técnicas de Cocultura , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP2E1 , Citocromo P-450 CYP3A , Elongases de Ácidos Graxos , Ácidos Graxos , Glucose , Glucose-6-Fosfatase , Humanos , Resistência à Insulina/fisiologia , Isoenzimas , Lipídeos , Fosfoenolpiruvato , Piruvatos , Ratos , Esteróis
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(4): 776-783, 2022 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-36008342

RESUMO

Primary human hepatocytes (PHH) are the gold standard of in vitro human liver model for drug screening. However, a problem of culturing PHH in vitro is the rapid decline of cytochrome P450 (CYP450) activity, which plays an important role in drug metabolism. In this study, thermo-responsive culture dishes were used to explore the conditions for murine embryonic 3T3-J2 fibroblasts to form cell sheet. Based on the cell sheet engineering technology, a three-dimensional (3D) "sandwich" co-culture system of 3T3-J2 cell sheet/PHH/collagen gel was constructed. The tissue structure and protein expression of the model section were observed by hematoxylin eosin staining and immunofluorescence staining respectively. Phenacetin and bupropion were used as substrates to determine the activity of CYP450. The contents of albumin and urea in the system were determined by enzyme linked immunosorbent assay (ELISA). The results showed that the complete 3T3-J2 cell sheet could be obtained when the cell seeding density was 1.5×106 /dish (35 mm dish) and the incubation time at low temperature was 60 min. Through cell sheet stacking, a 3D in vitro liver model was developed. Compared with the two-dimensional (2D) model, in the 3D model, the cell-cell and cell-matrix connections were tighter, the activities of cytochrome P450 CYP1A2 and cytochrome P450 CYP2B6 were significantly increased, and the secretion levels of albumin and urea were increased. These indexes could be maintained stably for 21 d. Therefore, cell sheet stacking is helpful to improve the level of liver function of 3D liver model. This model is expected to be used to predict the metabolism of low-clearance drugs in preclinical, which is of great significance for drug evaluation and other studies.


Assuntos
Hepatócitos , Fígado , Albuminas/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Hepatócitos/metabolismo , Humanos , Camundongos , Ureia/metabolismo
12.
Carbohydr Polym ; 285: 119235, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35287859

RESUMO

Manufacturing facile and low-cost wound dressings that simultaneously meet the needs of the entire repair process remains the major challenge of effective wound healing. Herein, a series of curdlan-tannic acid hybrid hydrogels were successfully fabricated through the annealing technique. Notedly, when the mixing weigh ratio was 1:1, the hydrogel exhibited excellent physicochemical properties, including swellability, degradability, water retention, porosity, and rheology. Additionally, the hydrogel did not display significant cytotoxicity to fibroblasts and the hemolysis rate at 12 h was 3%. Interestingly, the hybrid hydrogel showed multifunctional properties, including remarkable antioxidant, antibacterial, and rapid hemostasis effects reduce blood loss by 0.35 g, that were achieved through the temperature-dependent release of tannic acid. Moreover, a full-thickness skin defect animal model was used to verify that the multifunctional hydrogel could accelerate wound healing in vivo. These results suggest that this hybrid hydrogel is a promising candidate for the clinical treatment of full-thickness wounds.


Assuntos
Hemostáticos , Hidrogéis , Animais , Antibacterianos/química , Antioxidantes/farmacologia , Hemostasia , Hemostáticos/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Hidrogênio , Taninos/farmacologia , Taninos/uso terapêutico , Cicatrização , beta-Glucanas
13.
Int J Mol Sci ; 22(18)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34575832

RESUMO

Panax ginseng is a valuable traditional Chinese medicine in Northeast China. Ginsenoside, the active component of ginseng, has not been investigated much for its effects on aging and its underlying mechanism(s) of action. Here, we investigated the effects of total ginsenoside (TG), a mixture of the primary active ginsenosides from Panax ginseng, on the lifespan of Caenorhabditis elegans (C. elegans). We found that TG extended the lifespan of C. elegans and reduced lipofuscin accumulation. Moreover, TG increased the survival of C. elegans in response to heat and oxidative stress via the reduction of ROS. Next, we used RNA-seq to fully define the antiaging mechanism(s) of TG. The KEGG pathway analysis showed that TG can prolong the lifespan and is involved in the longevity regulating pathway. qPCR showed that TG upregulated the expression of nrh-80, daf-12, daf-16, hsf-1 and their downstream genes. TG also reduced the fat accumulation and promoted lipid metabolism. Moreover, TG failed to extend the lifespan of daf-16 and hsf-1 mutants, highlighting their role in the antiaging effects of TG in C. elegans. The four main constitution of TG were then confirmed by HPLC and included ginsenoside Re, Rg1, Rg2 and Rd. Of the ginsenosides, only ginsenoside Rd prolonged the lifespan of C. elegans to levels comparable to TG. These findings provided mechanistic insight into the antiaging effects of ginsenoside in C. elegans.


Assuntos
Ginsenosídeos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Animais , Biomarcadores , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/fisiologia , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma
14.
Int J Mol Sci ; 22(8)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924155

RESUMO

Ferulic acid (FA) is a naturally-occurring well-known potent antioxidant and free radical scavenger. FA supplementation is an effective strategy to delay aging, but the underlying mechanism remains unknown. In the present study, we examined the effects of FA on lifespan extension and its mechanism of FA in Caenorhabditis elegans (C. elegans). Results suggested that FA increased the lifespan of C. elegans, rather than altering the growth of E. coli OP50. Meanwhile, FA promoted the healthspan of C. elegans by improving locomotion and reducing fat accumulation and polyQ aggregation. FA increased the resistance to heat and oxidative stress through reducing ROS. The upregulating of the expression of the hlh-30, skn-1, and hsf-1 were involved in the FA-mediated lifespan extension. Furthermore, FA treatment had no impact on the lifespan of daf-2, hlh-30, skn-1, and hsf-1 mutants, confirming that insulin/IGF-1 signaling pathway and multiple longevity mechanisms were associated with the longevity mechanism of FA. We further found that mitochondrial signaling pathway was modulation involved in FA-mediated lifespan extension. With the results from RNA-seq results and mutants lifespan assay. These findings contribute to our knowledge of the lifespan extension and underlying mechanism of action of FA in C. elegans.


Assuntos
Ácidos Cumáricos/administração & dosagem , Suplementos Nutricionais , Fator de Crescimento Insulin-Like I/metabolismo , Insulina/metabolismo , Longevidade , Transdução de Sinais , Estresse Fisiológico , Animais , Autofagia , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Modelos Biológicos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
Food Funct ; 12(3): 1219-1231, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33432954

RESUMO

Caffeic acid (CA), a derivative of cinnamic acid, exists in various vegetables and fruits. Natural compounds as beneficial antioxidants play an important role in the research of Alzheimer's disease (AD). In this study, we evaluated the effects of CA against AD using the C. elegans models of AD. We found that CA significantly alleviated Aß-induced toxicity, increased lifespan, decreased body paralysis, and improved reproductive defects. Also, CA treatment increased resistance to heat and oxidative stress in N2 and CL4176. Moreover, reactive oxygen species (ROS) levels and polyglutamine (polyQ40) aggregate formation were reduced. Furthermore, the mechanistic studies revealed that CA activated transcription factor DAF-16 and its downstream targets SOD-3 and GST-4 to protect against Aß toxicity. Also, the heat shock proteins hsf-1 and hsp-16.2 mRNA were up-regulated in CL4176. Moreover, CA activated the mRNA expression of lgg-1. Lastly, the KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis of RNA-seq data revealed that there was a significant change in the metabolism-related pathways. Overall, these results suggested an underlying mechanism of action of CA in treating AD at an organism level.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Caenorhabditis elegans/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Doença de Alzheimer/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Ácidos Cafeicos/química , Quimiotaxia/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Estrutura Molecular , Óvulo/efeitos dos fármacos , Espécies Reativas de Oxigênio
16.
Colloids Surf B Biointerfaces ; 183: 110385, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31408781

RESUMO

Polypeptide carriers have a good cell compatibility, rich functionality, and facile synthesis and modification, make them promising materials as siRNA vectors. Phenylalanine dipeptide (FF) has been previously assessed as an siRNA vector and showed to have two major drawbacks, namely poor water solubility and poor serum stability. Herein, the FF backbone was modified by ligating a PEG-Arg-Ala (PEG-RA) sequence at the N-terminus to increase its hydrophilicity and serum stability. Arg is a typical amino acid in the cell penetrating peptide, which can increase the efficiency of cell internalization. Ala acts as a spacer to avoid steric hindrance. The target sequence PEG-RAFF was synthesized by a solid phase peptide synthesis. The morphology, particle size, and siRNA ratio were assessed by SEM, TEM, DLS, and gel electrophoresis. Further, MCF-7 cells were used as a model and survivin-siRNA as a passenger to assess cell internalization, inhibition of gene expression rate, and apoptosis rate using confocal microscopy, real-time PCR, and flow cytometry. At a concentration of 1 mg/mL, PEG-RAFF took the form of nanovesicles with a diameter of 154.74 ±â€¯14.36 nm. The optimal PEG-RAFF to siRNA ratio was N/P = 100:1. Compared with the control group, the red fluorescence of TAMRA(Carboxytetramethylrhodamine, Red fluorescence)-siRNA transfected into cells was clearly visible in the confocal microscope image. The inhibition rate of survivin was 67.99 ±â€¯10.31%, and the apoptotic rate was 16.07%. Therefore, PEG-RAFF has potential as an siRNA carrier in cancer treatment.


Assuntos
Apoptose/genética , Portadores de Fármacos , Nanopartículas/metabolismo , Polietilenoglicóis/química , RNA Interferente Pequeno/genética , Survivina/genética , Alanina/química , Arginina/química , Corantes Fluorescentes/metabolismo , Expressão Gênica , Humanos , Interações Hidrofóbicas e Hidrofílicas , Células MCF-7 , Nanopartículas/química , Tamanho da Partícula , Fenilalanina/química , RNA Interferente Pequeno/metabolismo , Rodaminas/metabolismo , Técnicas de Síntese em Fase Sólida , Survivina/antagonistas & inibidores , Survivina/metabolismo
17.
Mikrochim Acta ; 186(8): 586, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31363854

RESUMO

A dendrimer (termed G2) containing pyrene as the core and 9-phenylcarbazole (PCZ) on the periphery is shown to be a multi-functional fluorescent probe for iodide, iron(III) and mercury(II). It serves as the fluorometric/colorimetric dual-channel probe for these ions. As a fluorometric probe, the fluorescence of G2 is quenched both by iodide and iron(III). After that, the fluorescence of G2 which has been added iodide will recover when added mercury(II); as a colorimetric probe, the color of G2 solution can turn to yellow only by iodide which will change from yellow to colorless again when adding mercury(II). The color change is sensitive and observed visually at 0.1 mM for iodide. G2 also is an electroactive precursor for preparation of fluorescent films via electropolymerization. The resulting films can be used as the fluorescent films to sense the ions. This is attributed to the presence of a large specific surface, highly cross-linked microstructures and enhanced π conjugation. The electropolymerized film has blue fluorescence with excitation/emission maxima at 365/460 nm. The limits of detection (LOD) of G2 for iodide, iron(III) and mercury(II) were calculated to be 9.3, 37.1 and 22.0 nM in solution and 5.1, 12.0 and 6.1 nM in films, respectively. The linear range is from 2 to 10 µM for G2 electropolymerized films. The detection range is from 2 to 400 µM for iron(III) and mercury(II). The detection range is from 2 to 130 µM for iodide. For a third application, G2 displays compelling sensing performance in environmental systems and in living roundworms. Graphical abstractAs schematic presentation, after adding iodide, the fluorescence of G2 is quenched and the color changes to yellow. When adding Hg2+ to G2-iodide, the fluorescence and color of G2 recover. Iron(III) can also quench G2, but the color does not change.

18.
Chem Commun (Camb) ; 55(61): 8951-8954, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31289799

RESUMO

A new reconfigurable DNA nanocage based on a DNA origami method has been constructed to capture a tobacco mosaic virus (TMV) disk. We used a hairpin to control the transformation of the nanocage and a strand of TMV RNA to attract the TMV disk. Our design could inspire new DNA-protein complex designs.


Assuntos
DNA/química , Nanoestruturas/química , Vírus do Mosaico do Tabaco/química , Sequência de Bases , DNA/síntese química , DNA/genética , Sequências Repetidas Invertidas , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , RNA Viral/química
19.
J Mater Chem B ; 7(32): 4927-4932, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31359022

RESUMO

The combination of selenium and pillararenes to prepare selenium-containing pillararene-based biomaterials is of great significance for the development of biomedicine. Herein, using a covalent self-assembly strategy, we successfully developed new diselenium-containing ultrathin polymer nanocapsules based on lateral cross-linked pillararenes. The new system exhibited a very potent anticancer effect; additionally, the incorporation of the cleavable redox diselenium bond into the polymer nanocapsules provided a smart nanocarrier for drug delivery. Moreover, the polymer nanocapsules were developed for anticancer drug targeting delivery by loading an anticancer drug and introducing the tumor-penetrating peptide RGD through the host-guest interaction strategy. The targeting DOX-loaded diselenium-containing polymer nanocapsules exhibited enhanced stability, self-anticancer effect, targeted delivery and controlled drug release, resulting in effective combined inhibition of tumor progression.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Portadores de Fármacos/química , Nanocápsulas/química , Polímeros/química , Selênio/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Humanos , Células MCF-7 , Modelos Moleculares , Conformação Molecular , Oxirredução , Compostos de Amônio Quaternário/química
20.
Bioorg Chem ; 82: 332-339, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30428413

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative brain disease and is the most common cause of dementia in the elderly. The main hallmark of AD is the deposition of insoluble amyloid (Aß) outside the neuron, leading to amyloid plaques and neurofibrillary tangles in the brain. Deuterohemin-Ala-His-Thr-Val-Glu-Lys (DhHP-6), a novel porphyrin-peptide, has both microperoxidase activity and cell permeability. In the present study, DhHP-6 efficiently inhibited the aggregation of Aß and reduced the ß-sheet percentage of Aß from 89.1% to 78.3%. DhHP-6 has a stronger affinity (KD = 100 ±â€¯12 µM) for binding with Aß at Phe4, Arg5, Val18, Glu11 and Glu22. In addition, DhHP-6 (100 µM) significantly prolonged lifespan, alleviated paralysis and reduced Aß plaque formation in the Aß1-42 transgenic Caenorhabditis elegans CL4176 model of AD. Our results demonstrate that DhHP-6 is a potential drug candidate that efficiently protects a transgenic C. elegans model of Alzheimer's disease by inhibiting Aß aggregation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Caenorhabditis elegans/química , Sequestradores de Radicais Livres/farmacologia , Hemina/análogos & derivados , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/metabolismo , Multimerização Proteica/efeitos dos fármacos , Peptídeos beta-Amiloides/genética , Animais , Animais Geneticamente Modificados , Materiais Biomiméticos/farmacologia , Caenorhabditis elegans/genética , Hemina/farmacologia , Longevidade/efeitos dos fármacos , Simulação de Acoplamento Molecular , Paralisia/tratamento farmacológico , Fragmentos de Peptídeos/genética , Peroxidases/química , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta
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