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1.
Int J Biol Macromol ; 275(Pt 1): 133528, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945346

RESUMO

Burns are a prevalent type of injury worldwide, affecting tens of millions of people each year and significantly impacting the physical and psychological well-being of patients. Consequently, prompt treatment of burn wounds is imperative, with oxidative stress and excessive inflammation identified as primary factors contributing to delayed healing. In recent years, there has been growing interest in in situ crosslinked multifunctional hydrogels as a minimally invasive approach for personalized treatment delivery. To address these, a photocrosslinkable methacryloyl hyaluronic acid hydrogel scaffold embedded with chlorogenic acid/carboxymethyl chitosan nanoparticles (CGA/CMCS-HAMA, CCH), was developed for the treatment of burn wounds. The hydrogel prepared degraded by over 50 % by day 20, demonstrating stability and meeting the therapeutic requirements for burn wounds. Leveraging the extracellular matrix-like properties of HAMA and the antioxidant capabilities of CGA/CMCS NPs, this hydrogel demonstrates the ability to locally and continuously scavenge ROS and inhibit lipid peroxidation, inhibiting ferroptosis. Moreover, hydrogels well modulate the expression of macrophage- and fibroblast-associated inflammatory factors. Additionally, the hydrogel promotes cell adhesion and migration, further supporting the healing process. Overall, this innovative approach offers a safe and promising solution for burn wound treatment, addressing drug breakthrough and safety concerns while being adaptable to various irregular wound types.

2.
Adv Healthc Mater ; : e2400439, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38870451

RESUMO

Soft-bodied aquatic organisms have exhibited remarkable capabilities in navigating and moving within liquid environments serving as a profound inspiration for the development of bionic robots with intricate movements. Traditional rigid components are being replaced by stimulus-responsive soft materials such as hydrogels and shape memory polymers, leading to the creation of dynamically responsive soft robots. In this study, the development of a bionic robot inspired by the shape of an octopus and the adsorptive properties of its tentacles, specifically tailored for targeted stimulation and pH sensing in the cervix, are presented. This approach involves the design of a soft, water-based Janus adhesive hydrogel patch that adheres to specific parts of the cervix and responds to pH changes through external stimuli. The hydrogel patch incorporates inverse opal microstructures mimicking the legs of an octopus, to facilitate efficient and stable locomotion, unidirectional transport of biofluids, and pH-responsive behavior. This miniature bionic robot showcases controlled adhesion and precise unidirectional fluid transport highlighting its potential for targeted stimulus response and pH sensing in the uterine cervical tract. This breakthrough opens new avenues for medical applications within the expanding field of soft-bodied robotics.

3.
BMC Med Genomics ; 17(1): 159, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867275

RESUMO

BACKGROUND: Association between glucose and inflammatory bowel disease (IBD) was found in previous observational studies and in cohort studies. However, it is not clear whether these associations reflect causality. Thus, this study investigated whether there is such a causal relation between elevated glucose and IBD, Crohn's disease (CD) and ulcerative colitis (UC). METHODS: We performed a two-sample Mendelian Randomization (MR) with the independent genetic instruments identified from the largest available genome-wide association study (GWAS) for IBD (5,673 cases; 213,119 controls) and its main subtypes, CD and UC. Summarized data for glucose which included 200,622 cases and glycemic traits including HbA1c and type 2 diabetes(T2DM) were obtained from different GWAS studies. Primary and secondary analyses were conducted by preferentially using the radial inverse-variance weighted (IVW) approach. A number of other meta-analysis approach and sensitivity analyses were carried out to assess the robustness of the results. RESULTS: We did not find a causal effect of genetically predicted glucose on IBD as a whole (OR 0.858; 95% CI 0.649-1.135; P = 0.286). In subtype analyses glucose was also suggestively not associated with Crohn's disease (OR 0.22; 95% CI 0.04-1.00; P = 0.05) and ulcerative colitis (OR 0.940; 95% CI 0.628-1.407; P = 0.762). In the other direction, IBD and its subtypes were not related to glucose and glycemic traits. CONCLUSIONS: This MR study is not providing any evidence for a causal relationship between genetically predicted elevated glucose and IBD as well as it's subtypes UC and CD. Regarding the other direction, no causal associations could be found. Future studies with robust genetic instruments are needed to confirm this conclusion.


Assuntos
Estudo de Associação Genômica Ampla , Doenças Inflamatórias Intestinais , Análise da Randomização Mendeliana , Humanos , Doenças Inflamatórias Intestinais/genética , Glicemia , Polimorfismo de Nucleotídeo Único , Doença de Crohn/genética , Colite Ulcerativa/genética , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença
4.
Gels ; 10(5)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38786236

RESUMO

Hydrogels with adhesion properties and a wetted structure are promising alternatives to traditional wound dressing materials. The insufficiency of gelatin hydrogels in terms of their adhesive and mechanical strength limits their application in wound dressings. This work presents the design and preparation of a gelatin-based hydrogel functionalized with dopamine (DA) and layered double hydroxide (LDH). The combination of DA and LDH improves the hydrogel's adhesion properties in terms of interfacial adhesion and inner cohesion. Hydrogels with 8% DA and 4% LDH attained the highest adhesion strength of 266.5 kPa, which increased to 295.5 and 343.3 kPa after hydrophobically modifying the gelatin with octanoyl and decanoyl aldehydes, respectively. The gelatin-based hydrogels also demonstrated a macroporous structure, excellent biocompatibility, and a good anti-inflammatory effect. The developed hydrogels accelerated wound healing in Sprague Dawley rat skin full-thickness wound models.

5.
ACS Appl Bio Mater ; 7(6): 3556-3567, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38777621

RESUMO

Skin tissue engineering (STE) is widely regarded as an effective approach for skin regeneration. Several synthetic biomaterials utilized for STE have demonstrated favorable fibrillar characteristics, facilitating the regeneration of skin tissue at the site of injury, yet they have exhibited a lack of in situ degradation. Various types of skin regenerative materials, such as hydrogels, nanofiber scaffolds, and 3D-printing composite scaffolds, have recently emerged for use in STE. Electrospun nanofiber scaffolds possess distinct advantages, such as their wide availability, similarity to natural structures, and notable tissue regenerative capabilities, which have garnered the attention of researchers. Hence, electrospun nanofiber scaffolds may serve as innovative biological materials possessing the necessary characteristics and potential for use in tissue engineering. Recent research has demonstrated the potential of electrospun nanofiber scaffolds to facilitate regeneration of skin tissues. Nevertheless, there is a need to enhance the rapid degradation and limited mechanical properties of electrospun nanofiber scaffolds in order to strengthen their effectiveness in soft tissue engineering applications in clinical settings. This Review centers on advanced research into electrospun nanofiber scaffolds, encompassing preparation methods, materials, fundamental research, and preclinical applications in the field of science, technology, and engineering. The existing challenges and prospects of electrospun nanofiber scaffolds in STE are also addressed.


Assuntos
Materiais Biocompatíveis , Nanofibras , Pele , Engenharia Tecidual , Alicerces Teciduais , Nanofibras/química , Alicerces Teciduais/química , Humanos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Teste de Materiais , Animais , Tamanho da Partícula
6.
ACS Appl Mater Interfaces ; 16(17): 21736-21745, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38630008

RESUMO

In the quest to develop advanced monitoring systems for intestinal peristaltic stress, this study introduces a groundbreaking approach inspired by nature's sensory networks. By the integration of novel materials and innovative manufacturing techniques, a multifunctional Janus hydrogel patch has been engineered. This unique patch not only demonstrates superior stress-sensing capabilities in the intricate intestinal environment but also enables adhesion to wet tissue surfaces. This achievement opens new avenues for real-time physiological monitoring and potential therapeutic interventions in the realm of gastrointestinal health.


Assuntos
Hidrogéis , Hidrogéis/química , Catéteres , Pressão , Animais , Coloides/química , Humanos , Intestinos/fisiologia
7.
Colloids Surf B Biointerfaces ; 234: 113669, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38039824

RESUMO

In vivo surgical interventions require effective management of biofluids, including controlling bleeding and removing excess biofluids such as bile, wound exudate, and blood. To address these issues, recent advances have emerged, such as self-sealing needles, drug-eluting stents, and shear-thinning hydrogels. However, complications associated with intestinal mucosal injury and secondary damage still persist. Therefore, a multifunctional stent is urgently required that can effectively remove excessive biofluid. Surface wettability of biliary stents is crucial in biofluid management, and conventional coatings can cause adhesion to wound tissue. To overcome this issue, we developed an interpenetrating Janus wettability stent coating, enabling unidirectional draining of excessive biofluid from its hydrophobic side to hydrophilic side, thereby preventing biofluid from wetting the wound. Furthermore, we demonstrate a directional biofluid movement using a self-pumping dressing in an infected tissue model, providing a new approach for in situ biofluid collection and disease diagnosis by detecting metal ion changes. Overall, our integrated system presents an opportunity to design wound dressings with effective biofluid management and metal ion detection capabilities.


Assuntos
Biônica , Stents Farmacológicos , Stents , Metais
8.
Radiol Case Rep ; 19(2): 825-830, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38111550

RESUMO

This study presents a rare case of an older woman with an intracranial mesenchymal tumor in the right frontal and parietal lobes. Despite prompt surgical intervention, her condition rapidly deteriorated because of tumor dissemination, leading to her demise. We highlight the tumor's marked invasiveness and heterogeneity, coupled with a propensity for distant systemic metastasis, which negatively impacted the patient's prognosis. This particular clinical behavior had not been previously reported, making this a novel observation. Thus, through a comprehensive review of relevant literature, we aim to provide valuable insights for further understanding, diagnosing, and treating such tumors.

9.
World J Hepatol ; 15(7): 867-882, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37547030

RESUMO

Metabolic-associated fatty liver disease (MAFLD) is one of the most common chronic liver diseases worldwide. In recent years, the occurrence rate of MAFLD has been on the rise, mainly due to lifestyle changes, high-calorie diets, and imbalanced dietary structures, thereby posing a threat to human health and creating heavy social and economic burdens. With the development of 16S sequencing and integrated multi-omics analysis, the role of the gut microbiota (GM) and its metabolites in MAFLD has been further recognized. The GM plays a role in digestion, energy metabolism, vitamin synthesis, the prevention of pathogenic bacteria colonisation, and immunoregulation. The gut-liver axis is one of the vital links between the GM and the liver. Toxic substances in the intestine can enter the liver through the portal vascular system when the intestinal barrier is severely damaged. The liver also influences the GM in various ways, such as bile acid circulation. The gut-liver axis is essential in maintaining the body's normal physiological state and plays a role in the onset and prognosis of many diseases, including MAFLD. This article reviews the status of the GM and MAFLD and summarizes the GM characteristics in MAFLD. The relationship between the GM and MAFLD is discussed in terms of bile acid circulation, energy metabolism, micronutrients, and signalling pathways. Current MAFLD treatments targeting the GM are also listed.

10.
Nanoscale ; 15(29): 12212-12219, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37395090

RESUMO

Increasing attention has been paid recently to superwettability and its prospective potential applications in various fields. A new approach towards the establishment of flexible, self-assembled superhydrophobic surfaces with self-reported wettability on a variety of substrates has been advanced. The approach involves the fabrication of a dense monolayer of photonic crystal films that possess a layered structure with superior adhesion at the liquid-gas-solid interface. Thus, the resulting hierarchical photonic crystal film with a structurally hydrophobic surface offers a promising addition to the creation of durable and flexible superhydrophobic surfaces across a variety of substrates that exhibit the self-reported wettability. Furthermore, a bifunctional membrane that can effectively remove oil and adsorb heavy metal ions contained in wastewater has been developed for potential use in large-scale industrial wastewater treatment. This research sheds fresh light on the application of bionics and the lotus and mussel functions in oil/water separation.

11.
Front Immunol ; 14: 1296889, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38288127

RESUMO

Background and objectives: Observational study has found inflammatory bowel disease to be associated with multiple extraintestinal manifestations. To this end, we characterized the causal association between inflammatory bowel disease and extraintestinal manifestations through a Mendelian randomization study and further explored the role of intestinal flora in inflammatory bowel disease and the extraintestinal manifestations associated with it. Materials and methods: We genetically predicted the causal relationship between inflammatory bowel disease and twenty IBD-related extraintestinal manifestations (including sarcoidosis, iridocyclitis, interstitial lung disease, atopic dermatitis, ankylosing spondylitis, psoriatic arthropathies, primary sclerosing cholangitis, primary biliary cholangitis). We used the full genome-wide association study (GWAS) summary statistics on gut microbiota in 18,340 participants from 24 cohorts to explore its role in the casual relationships between IBD and IBD-related extraintestinal manifestations. Inverse variance weighting (IVW) was used as the main analytical method to assess the causal associations. We performed Cochran's Q test to examine the heterogeneity. To assess the robustness of the IVW results, we further performed sensitivity analyses including the weighted median method, MR-Egger regression, and Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) test. The leave-one-out sensitivity analysis was further performed to monitor if significant associations were dominated by a single nucleotide polymorphism (SNP). Result: A total of eight extraintestinal manifestations were found to be at elevated risk of development due to inflammatory bowel diseases. A total of 11 causal relationships were found between IBD and gut microbiota, four of which were stable. Between gut microbiota and these eight extraintestinal manifestations, a total of 67 nominal causal associations were identified, of which 13 associations were stable, and notably 4 associations were strongly correlated. Conclusion: Through the two-sample MR analysis, we identified extraintestinal manifestations that were causally associated with inflammatory bowel disease and obtained multiple associations from inflammatory bowel disease and gut microbiota, and gut microbiota and extraintestinal manifestations in further analyses. These associations may provide useful biomarkers and potential targets for pathogenesis and treatment.


Assuntos
Artrite Psoriásica , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Humanos , Estudo de Associação Genômica Ampla , Doenças Inflamatórias Intestinais/genética , Análise da Randomização Mendeliana
12.
Front Vet Sci ; 9: 889586, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720856

RESUMO

The ß-Glucans widely exist in plants and edible fungi, and their diverse bioactivities and good physicochemical properties have been widely reported. In addition, ß-glucan intravenous injections (such as lentinan and schizophyllan) have been clinically used as immunomodulators and antitumor polysaccharides. However, the pharmacokinetic studies of ß-glucans only stay on the level of plasma concentration and biodistribution in vivo, and little is known about their metabolism and degradation in vivo, which severely limits the further application of ß-glucans in the field of medicine and biomaterials. The aim of this paper is to explore the metabolism and degradation process of lentinan (as a representative of ß-glucans) in vivo by labeling it with water-soluble fluorescein 5-([4, 6-Dichlorotriazin-2-yl]amino)fluorescein (DTAF). Fluorescently labeled lentinan (FLNT) was intravenously administered to rats at a single dose of 8 mg/kg. The degradation of LNT in blood, liver, kidney, and urine was evaluated by the gel permeation chromatography. Our results showed that although LNT could be degraded in blood, liver, kidney, and urine, there were still some prototypes until excreted in urine due to the incomplete degradation of LNT in each step. To the best of our knowledge, this is the first report to comprehensively study LNT metabolic degradation in rats. These results provide an important reference for further exploration and application of LNT and other ß-glucans.

13.
Biomater Sci ; 10(15): 4126-4139, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35762682

RESUMO

Inspired by the mussel foot proteins, polydopamine nanoparticles (PDA NPs) are often used to design hydrogel wound dressings due to their strong wet adhesion. However, additional antibiotics or nanometal bactericides are always required to enhance their poor antibacterial activity, which will cause drug resistance and toxic side effects. Herein, self-assembly confined PDA NPs (SC-PDA NPs, <50 nm) are employed as a freestanding antibacterial ingredient for constructing an ideal hydrogel wound dressing, which maintains relatively strong reducibility and size effect. Through a rapid gelation (within 10 s) strategy triggered by electrostatic complexation, an antibacterial hydrogel system is obtained, in which the in situ self-assembly of the SC-PDA NPs continues, endowing the gel with outstanding antibacterial activity, especially against methicillin-resistant Staphylococcus aureus (MRSA, >99.9%). With the continuous in situ self-assembly, the size of the PDA NPs increases (>200 nm), eventually giving the gel an efficient photothermal therapy effect. Moreover, the gel presents a relatively strong wet adhesion (63 kPa), superior biocompatibility and non-immunogenicity. This work offers innovative insights into the antibacterial mechanism of SC-PDA NPs and provides a novel design for constructing safe antibacterial hydrogel wound dressings, demonstrating great potential applications in superbug-infected wound healing.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecção dos Ferimentos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Humanos , Hidrogéis/farmacologia , Indóis , Terapia Fototérmica , Polímeros , Cicatrização , Infecção dos Ferimentos/tratamento farmacológico
14.
ISA Trans ; 122: 163-171, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33972079

RESUMO

The visualization of an operating state of industrial processes allows operators to identify and diagnose faults intuitively and quickly. The identification and diagnosis of faults are important for ensuring industrial production safety. A method that combines variable-weighted Fisher discriminant analysis (VWFDA), t-distributed stochastic neighbor embedding (t-SNE), and multiple extreme learning machines (ELMs) is proposed for visual process monitoring. First, the VWFDA weighs variables on the basis of their contribution to the fault, thereby amplifying the fault information. The VWFDA is used to extract feature vectors from industrial data, and normal state and various fault states can be separated from each other in the space formed by these feature vectors. Second, t-SNE is used to visualize these feature vectors. Third, given that t-SNE lacks a transformation matrix during dimension reduction, one ELM is used for each class data of t-SNE to obtain the mapping relation from its input data to its mapping points. Finally, the VWFDA and multiple trained ELMs are combined for online process monitoring. The performance of the proposed approach is compared with that of FDA-t-SNE and other methods on the basis of the Tennessee Eastman process, thereby confirming that the proposed approach is advantageous for visual industrial process monitoring.

15.
Nanomaterials (Basel) ; 11(7)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34361208

RESUMO

In recent years, electrospun nanofibers have attracted extensive attention due to their large specific surface area, high porosity, and controllable shape. Among the many applications of electrospinning, electrospun nanofibers used in fields such as tissue engineering, food packaging, and air purification often require some antibacterial properties. This paper expounds the development potential of electrospinning in the antibacterial field from four aspects: fiber morphology, antibacterial materials, antibacterial mechanism, and application fields. The effects of fiber morphology and antibacterial materials on the antibacterial activity and characteristics are first presented, then followed by a discussion of the antibacterial mechanisms and influencing factors of these materials. Typical application examples of antibacterial nanofibers are presented, which show the good prospects of electrospinning in the antibacterial field.

16.
Nanomaterials (Basel) ; 11(5)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067723

RESUMO

The phenomenon of drug burst release is the main problem in the field of drug delivery systems, as it means that a good therapeutic effect cannot be acheived. Nanofibers developed by electrospinning technology have large specific surface areas, high porosity, and easily controlled morphology. They are being considered as potential carriers for sustained drug release. In this paper, we obtained polycaprolactone (PCL)/polylactic acid (PLA) core-shell porous drug-carrying nanofibers by using coaxial electrospinning technology and the nonsolvent-induced phase separation method. Roxithromycin (ROX), a kind of antibacterial agent, was encapsulated in the core layer. The morphology, composition, and thermal properties of the resultant nanofibers were characterized by scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA). Besides this, the in vitro drug release profile was investigated; it showed that the release rate of the prepared coaxial porous nanofibers with two different pore sizes was 30.10 ± 3.51% and 35.04 ± 1.98% in the first 30 min, and became 92.66 ± 3.13% and 88.94 ± 1.58% after 14 days. Compared with the coaxial nonporous nanofibers and nanofibers prepared by uniaxial electrospinning with or without pores, the prepared coaxial porous nanofibers revealed that the burst release was mitigated and the dissolution rate of the hydrophobic drugs was increased. The further antimicrobial activity demonstrated that the inhibition zone diameter of the coaxial nanofibers with two different pore sizes was 1.70 ± 0.10 cm and 1.73 ± 0.23 cm, exhibiting a good antibacterial effect against Staphylococcus aureus. Therefore, the prepared nanofibers with the coaxial porous structures could serve as promising drug delivery systems.

17.
ACS Appl Mater Interfaces ; 12(50): 56470-56479, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33270426

RESUMO

Flexible sensors based on conductive hydrogel show great potential in electronic skin and human-machine interface. However, pure water in hydrogel inevitably freezes or rapidly evaporates under extreme temperatures, leading to inadequate fulfillment of sensor performances. Herein, a well-designed strategy is reported for fabricating extreme temperature-tolerant gel-based sensors. By immersing a gelatin/polyacrylamide (PAAm)-clay composite (GC) hydrogel into a ZnCl2/water/glycerol system, a phase-transition-tunable gel (PTTGC gel) is obtained with outstanding antifreezing (-82 °C) and long-lasting moisture (70 °C, more than 40 days) properties. Meanwhile, the gel also presents good antibacterial activity and biocompatibility attributing to Zn2+ and gelatin, respectively. Then, a dual-response sensor with a wide operating temperature (-60 to 60 °C) is proposed, presenting high stress and temperature sensitivities and long-term stability. The sensor will meet the needs of the human-machine interface for scientific investigation and data monitoring in polar, desert, etc.


Assuntos
Antibacterianos/química , Hidrogéis/química , Resinas Acrílicas/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Interfaces Cérebro-Computador , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cloretos/química , Escherichia coli/efeitos dos fármacos , Gelatina/química , Glicerol/química , Humanos , Transição de Fase , Staphylococcus aureus/efeitos dos fármacos , Temperatura , Água/química , Compostos de Zinco/química
18.
Materials (Basel) ; 13(17)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847000

RESUMO

A new gelatin methacrylamine (GelMA)-poly (ethylene glycol) diacrylate (PEGDA)-nano hydroxyapatite (nHA) composite hydrogel scaffold was developed using UV photo-crosslinking technology. The Ca2+ from nHA can form a [HO]Ca2+ [OH] bridging structure with the hydroxyl group in GelMA, thereby enhancing the stability. Compared with GelMA-PEGDA hydrogel, the addition of nHA can control the mechanical properties of the composite hydrogel and reduce the degradation rate. In vitro cell culture showed that osteoblast can adhere and proliferate on the surface of the hydrogel, indicating that the GelMA-PEGDA-nHA hydrogel had good cell viability and biocompatibility. Furthermore, GelMA-PEGDA-nHA has excellent injectability and rapid prototyping properties and is a promising 3D printed bone repair scaffold material.

19.
J Agric Food Chem ; 68(29): 7630-7640, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32633950

RESUMO

It has been recognized that collagen peptides of MW 878 Da (CP1) promote osteoblast proliferation and mineralization. The objective of this study is to identify the peptides responsible for proliferation of osteoblast growth, enhancement of ALP (alkaline phosphatase) activity in osteoblasts and promotion of osteoblast mineralization. To this end, the CP1 were fractioned by a series of chromatography procedures, and 51 peptides from the fraction possessing the most powerful cell proliferation ability were identified by LC-MS-MS. The peptides, GPAGPSGPAGK and GPPGSPGPR, were validated on a simultaneous basis as possessing enhanced bioactivity-inducing properties. In particular, the ALP activity of the cells treated with these two peptides was almost twice that of the control cells. Hydrogen bonds were formed, and the hydrophobic interactions with the EGFR (epidermal growth factor receptor) might be responsible for the osteoblast proliferation activity. On this basis, the two peptides might be potential lead compounds against osteoporosis and osteoarthritis.


Assuntos
Proliferação de Células/efeitos dos fármacos , Gelatina/química , Osteoblastos/citologia , Osteogênese/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Bovinos , Linhagem Celular , Espectrometria de Massas , Camundongos , Peso Molecular , Osteoblastos/efeitos dos fármacos , Peptídeos/química , Hidrolisados de Proteína/química , Hidrolisados de Proteína/farmacologia
20.
Langmuir ; 36(24): 6749-6756, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32419468

RESUMO

We have constructed a novel gated nanocarrier for the real-time monitoring of drug release, consisting of three parts: (i) mesoporous silica nanoparticles (MSNs) as the drug carrier, (ii) chitosan as the nanovalve to block and unlock the pores, and (iii) 1,8-naphthalimide fluorophore as a connecting arm and fluorescent signal source. In the absence of glutathione (GSH), the integrity of the system results in the formation of pores in a closed state and the sulfone would block the intramolecular charge transfer (ICT) process, leading to no fluorescence emission. However, the nucleophilic attack of GSH can cause the removal of the chitosan and recovery of ICT property, thus triggering drug release and green fluorescence emission. The results demonstrate that the change of GSH concentration in vivo or vitro would lead to a change in drug release as well as a concurrent change in fluorescence signal, which can expand the application of our gated nanocarrier for monitoring different drug release in real time.


Assuntos
Quitosana , Nanopartículas , Doxorrubicina , Portadores de Fármacos , Liberação Controlada de Fármacos , Porosidade , Dióxido de Silício
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