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1.
Proc Natl Acad Sci U S A ; 119(44): e2208593119, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36279462

RESUMO

Supramolecular self-assemblies of hydrophilic macromolecules functionalized with hydrophobic, structure-directing components have long been used for drug delivery. In these systems, loading of poorly soluble compounds is typically achieved through physical encapsulation during or after formation of the supramolecular assembly, resulting in low encapsulation efficiencies and limited control over release kinetics, which are predominately governed by diffusion and carrier degradation. To overcome these limitations, amphiphilic prodrugs that leverage a hydrophobic drug as both the therapeutic and structure-directing component can be used to create supramolecular materials with higher loading and controlled-release kinetics using biodegradable or enzymatically cleavable linkers. Here, we report the design, synthesis, and characterization of a library of supramolecular polymer prodrugs based on poly(ethylene glycol) (PEG) and the proregenerative drug 1,4-dihydrophenonthrolin-4-one-3-carboxylic acid (DPCA). Structure-property relationships were elucidated through experimental characterization of prodrug behavior in both the wet and dry states using scattering techniques and electron microscopy and corroborated by coarse-grained modeling. Molecular architecture and the hydrophobic-to-hydrophilic ratio of PEG-DPCA conjugates strongly influenced their physical state in water, ranging from fully soluble to supramolecular spherical assemblies and nanofibers. Molecular design and supramolecular structure, in turn, were shown to dramatically alter hydrolytic and enzymatic release and cellular transport of DPCA. In addition to potentially expanding therapeutic options for DPCA through control of supramolecular assemblies, the design principles elaborated here may inform the development of other supramolecular prodrugs based on hydrophobic small-molecule compounds.


Assuntos
Pró-Fármacos , Pró-Fármacos/química , Preparações de Ação Retardada , Polietilenoglicóis/química , Água , Ácidos Carboxílicos
2.
Small ; : e2309634, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38845070

RESUMO

A novel green-absorbing organic molecule featuring dual intramolecular chalcogen bonds is synthesized and characterized. This molecule incorporates two such bonds: one between a tellurium atom and the oxygen atom of a carbonyl moiety, and the other between the tellurium atom and the adjacent nitrogen atom within a pyridine moiety. The molecule, featuring dual intramolecular chalcogen bonds exhibits a narrow absorption spectrum and elevated absorption coefficients, closely aligned with a resonance parameter of approximately 0.5. This behavior is due to its cyanine-like characteristics and favorable electrical properties, which are a direct result of its rigid, planar molecular structure. Therefore, this organic molecule forming dual intramolecular chalcogen bonds achieves superior optoelectronic performance in green-selective photodetectors, boasting an external quantum efficiency of over 65% and a full-width at half maximum of less than 95 nm while maintaining the performance after 1000 h of heating aging at 85 °C. Such organic photodetectors are poised to enhance stacked organic photodetector-on-silicon hybrid image sensors, paving the way for the next-generation of high-resolution and high-sensitivity image sensors.

3.
Nano Lett ; 23(13): 5934-5942, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37382460

RESUMO

Herein, we highlight a novel finding that ferritin can play a crucial role in the "self-healing lifetime" of soft phenolic materials. Ferritin interacts with a catechol-functionalized polymer to form a self-healable and adhesive hydrogel bidirectionally by providing and retrieving Fe3+. As a result of its unique role as a nanoshuttle to store and release iron, ferritin significantly increases the self-healing lifetime of the hydrogel compared with that afforded by catechol-Fe3+ coordination through direct Fe3+ addition without ferritin. Ferritin also induces stable oxidative coupling between catechol moieties following metal coordination, which contributes to double cross-linking networks of catechol-catechol adducts and catechol-Fe3+ coordination. Thus, ferritin-mediated cross-linking can provide phenolic hydrogels with the advantages of hydrogels prepared by both metal coordination and oxidative coupling, thereby overcoming the limitations of the current cross-linking methods of phenolic hydrogels and broadening their versatility in biomedical applications.

4.
Int J Mol Sci ; 24(9)2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37175897

RESUMO

Cinnamon is a natural spice with a wide range of pharmacological functions, including anti-microbial, antioxidant, and anti-tumor activities. The aim of this study is to investigate the effects of cinnamaldehyde-rich cinnamon extract (CRCE) on the colorectal cancer cell lines HCT 116 and HT-29. The gas chromatography mass spectrometry analysis of a lipophilic extract of cinnamon revealed the dominance of trans-cinnamaldehyde. Cells treated with CRCE (10-60 µg/mL) showed significantly decreased cell viability in a time- and dose-dependent manner. We also observed that cell proliferation and migration capacity were inhibited in CRCE-treated cells. In addition, a remarkable increase in the number of sub-G1-phase cells was observed with arrest at the G2 phase by CRCE treatment. CRCE also induced mitochondrial stress, and finally, CRCE treatment resulted in activation of apoptotic proteins Caspase-3, -9, and PARP and decreased levels of mu-2-related death-inducing gene protein expression with BH3-interacting domain death agonist (BID) activation.


Assuntos
Cinnamomum zeylanicum , Neoplasias do Colo , Humanos , Cinnamomum zeylanicum/química , Apoptose , Neoplasias do Colo/tratamento farmacológico , Células HT29 , Morte Celular , Proliferação de Células , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Sobrevivência Celular
5.
Haemophilia ; 27(4): 563-573, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34128300

RESUMO

INTRODUCTION: Reports on patients' satisfaction and preferred characteristics for treatments would be worthwhile when choosing an optimal treatment reflecting patients' perspectives. AIM: To identify the characteristics and treatment patterns of patients with haemophilia A, or their caregivers, in Korea and explore patient preferences and satisfaction with their treatment. METHODS: This cross-sectional, multicentre, observational study was conducted from April 2018 to September 2019 at six nationwide hospitals and three Korea Hemophilia Foundation clinics. Patients aged ≥16 years, or legal caregivers of paediatric patients, who had used factor VIII (FVIII) concentrates for ≥1 month were enrolled. Satisfaction with treatment was measured using the Treatment Satisfaction Questionnaire for Medication (TSQM); preference was evaluated using discrete choice experiment (DCE), with 10 series of two hypothetical treatment options created from D-efficient block design, which varied across five attributes. RESULTS: Overall, 505 patients (mean age 31 years) were enrolled in the study. Patients had received FVIII concentrate for an average of 102.9 months (prophylaxis: 53.5%; on-demand: 22.2%). Mean TSQM scores were 64.6 (effectiveness domain), 97.9 (side effects), 57.1 (convenience) and 66.8 (global satisfaction). The number of vials per injection, and the frequency of drug administration, was significantly associated with treatment satisfaction. According to DCE, simpler treatment options were preferred by patients/caregivers. CONCLUSION: The lowest satisfaction levels were shown in the treatment convenience domain. Patients/parents preferred simpler and easier treatment characteristics. In an attempt to enhance the overall satisfaction of patients and caregivers with treatment, consideration of more convenient characteristics is required in future decisions regarding treatment selection.


Assuntos
Hemofilia A , Criança , Estudos Transversais , Hemofilia A/tratamento farmacológico , Humanos , Recém-Nascido , Pais , Preferência do Paciente , Satisfação do Paciente , Satisfação Pessoal
6.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807864

RESUMO

INTRODUCTION: Chronic inflammation and impaired neovascularization play critical roles in delayed wound healing in diabetic patients. To overcome the limitations of current diabetic wound (DBW) management interventions, we investigated the effects of a catechol-functionalized hyaluronic acid (HA-CA) patch combined with adipose-derived mesenchymal stem cells (ADSCs) in DBW mouse models. METHODS: Diabetes in mice (C57BL/6, male) was induced by streptozotocin (50 mg/kg, >250 mg/dL). Mice were divided into four groups: control (DBW) group, ADSCs group, HA-CA group, and HA-CA + ADSCs group (n = 10 per group). Fluorescently labeled ADSCs (5 × 105 cells/100 µL) were transplanted into healthy tissues at the wound boundary or deposited at the HA-CA patch at the wound site. The wound area was visually examined. Collagen content, granulation tissue thickness and vascularity, cell apoptosis, and re-epithelialization were assessed. Angiogenesis was evaluated by immunohistochemistry, quantitative real-time polymerase chain reaction, and Western blot. RESULTS: DBW size was significantly smaller in the HA-CA + ADSCs group (8% ± 2%) compared with the control (16% ± 5%, p < 0.01) and ADSCs (24% ± 17%, p < 0.05) groups. In mice treated with HA-CA + ADSCs, the epidermis was regenerated, and skin thickness was restored. CD31 and von Willebrand factor-positive vessels were detected in mice treated with HA-CA + ADSCs. The mRNA and protein levels of VEGF, IGF-1, FGF-2, ANG-1, PIK, and AKT in the HA-CA + ADSCs group were the highest among all groups, although the Spred1 and ERK expression levels remained unchanged. CONCLUSIONS: The combination of HA-CA and ADSCs provided synergistic wound healing effects by maximizing paracrine signaling and angiogenesis via the PI3K/AKT pathway. Therefore, ADSC-loaded HA-CA might represent a novel strategy for the treatment of DBW.


Assuntos
Tecido Adiposo/metabolismo , Bandagens , Diabetes Mellitus Experimental/terapia , Angiopatias Diabéticas/terapia , Ácido Hialurônico , Transplante de Células-Tronco , Células-Tronco/metabolismo , Cicatrização , Ferimentos e Lesões/terapia , Tecido Adiposo/patologia , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/patologia , Feminino , Humanos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Masculino , Camundongos , Células-Tronco/patologia , Ferimentos e Lesões/metabolismo , Ferimentos e Lesões/patologia
7.
Int J Mol Sci ; 21(15)2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32759789

RESUMO

Despite multitudes of reports on cancer remedies available, we are far from being able to declare that we have arrived at that defining anti-cancer therapy. In recent decades, researchers have been looking into the possibility of enhancing cell death-related signaling pathways in cancer cells using pro-apoptotic proteins. Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and Mu-2/AP1M2 domain containing, death-inducing (MUDENG, MuD) have been established for their ability to bring about cell death specifically in cancer cells. Targeted cell death is a very attractive term when it comes to cancer, since most therapies also affect normal cells. In this direction TRAIL has made noteworthy progress. This review briefly sums up what has been done using TRAIL in cancer therapeutics. The importance of MuD and what has been achieved thus far through MuD and the need to widen and concentrate on applicational aspects of MuD has been highlighted. This has been suggested as the future perspective of MuD towards prospective progress in cancer research.


Assuntos
Complexo 1 de Proteínas Adaptadoras/genética , Subunidades mu do Complexo de Proteínas Adaptadoras/genética , Proteínas Reguladoras de Apoptose/genética , Neoplasias/tratamento farmacológico , Ligante Indutor de Apoptose Relacionado a TNF/genética , Complexo 1 de Proteínas Adaptadoras/antagonistas & inibidores , Subunidades mu do Complexo de Proteínas Adaptadoras/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias/genética , Neoplasias/patologia , Transdução de Sinais/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/antagonistas & inibidores
8.
Biomacromolecules ; 18(10): 3060-3072, 2017 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-28876908

RESUMO

Electrically conductive hyaluronic acid (HA) hydrogels incorporated with single-walled carbon nanotubes (CNTs) and/or polypyrrole (PPy) were developed to promote differentiation of human neural stem/progenitor cells (hNSPCs). The CNT and PPy nanocomposites, which do not easily disperse in aqueous phases, dispersed well and were efficiently incorporated into catechol-functionalized HA (HA-CA) hydrogels by the oxidative catechol chemistry used for hydrogel cross-linking. The prepared electroconductive HA hydrogels provided dynamic, electrically conductive three-dimensional (3D) extracellular matrix environments that were biocompatible with hNSPCs. The HA-CA hydrogels containing CNT and/or PPy significantly promoted neuronal differentiation of human fetal neural stem cells (hfNSCs) and human induced pluripotent stem cell-derived neural progenitor cells (hiPSC-NPCs) with improved electrophysiological functionality when compared to differentiation of these cells in a bare HA-CA hydrogel without electroconductive motifs. Calcium channel expression was upregulated, depolarization was activated, and intracellular calcium influx was increased in hNSPCs that were differentiated in 3D electroconductive HA-CA hydrogels; these data suggest a potential mechanism for stem cell neurogenesis. Overall, our bioinspired, electroconductive HA hydrogels provide a promising cell-culture platform and tissue-engineering scaffold to improve neuronal regeneration.


Assuntos
Hidrogéis/química , Células-Tronco Neurais/citologia , Neurogênese , Alicerces Teciduais/química , Catecóis/química , Linhagem Celular , Condutividade Elétrica , Humanos , Ácido Hialurônico/química , Hidrogéis/farmacologia , Nanotubos de Carbono/química , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Polímeros/química , Pirróis/química
9.
Small ; 12(45): 6266-6278, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27717233

RESUMO

Using small interfering RNA (siRNA) to regulate gene expression is an emerging strategy for stem cell manipulation to improve stem cell therapy. However, conventional methods of siRNA delivery into stem cells based on solution-mediated transfection are limited due to low transfection efficiency and insufficient duration of cell-siRNA contact during lengthy culturing protocols. To overcome these limitations, a bio-inspired polymer-mediated reverse transfection system is developed consisting of implantable poly(lactic-co-glycolic acid) (PLGA) scaffolds functionalized with siRNA-lipidoid nanoparticle (sLNP) complexes via polydopamine (pDA) coating. Immobilized sLNP complexes are stably maintained without any loss of siRNA on the pDA-coated scaffolds for 2 weeks, likely due to the formation of strong covalent bonds between amine groups of sLNP and catechol group of pDA. siRNA reverse transfection with the pDA-sLNP-PLGA system does not exhibit cytotoxicity and induces efficient silencing of an osteogenesis inhibitor gene in human adipose-derived stem cells (hADSCs), resulting in enhanced osteogenic differentiation of hADSCs. Finally, hADSCs osteogenically committed on the pDA-sLNP-PLGA scaffolds enhanced bone formation in a mouse model of critical-sized bone defect. Therefore, the bio-inspired reverse transfection system can provide an all-in-one platform for genetic modification, differentiation, and transplantation of stem cells, simultaneously enabling both stem cell manipulation and tissue engineering.


Assuntos
Tecido Adiposo/citologia , Diferenciação Celular/fisiologia , Osteogênese/fisiologia , Células-Tronco/citologia , Regeneração Óssea/genética , Regeneração Óssea/fisiologia , Diferenciação Celular/genética , Humanos , Ácido Láctico/química , Osteogênese/genética , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , RNA Interferente Pequeno/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química
10.
Biomacromolecules ; 17(6): 1939-48, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27112904

RESUMO

Over the last few decades, stem cell therapies have been highlighted for their potential to heal damaged tissue and aid in tissue reconstruction. However, materials used to deliver and support implanted cells often display limited efficacy, which has resulted in delaying translation of stem cell therapies into the clinic. In our previous work, we developed a mussel-inspired, catechol-functionalized hyaluronic acid (HA-CA) hydrogel that enabled effective cell transplantation due to its improved biocompatibility and strong tissue adhesiveness. The present study was performed to further expand the utility of HA-CA hydrogels for use in stem cell therapies to treat more clinically relevant tissue defect models. Specifically, we utilized HA-CA hydrogels to potentiate stem cell-mediated angiogenesis and osteogenesis in two tissue defect models: critical limb ischemia and critical-sized calvarial bone defect. HA-CA hydrogels were found to be less cytotoxic to human adipose-derived stem cells (hADSCs) in vitro compared to conventional photopolymerized HA hydrogels. HA-CA hydrogels also retained the angiogenic functionality of hADSCs and supported osteogenic differentiation of hADSCs. Because of their superior tissue adhesiveness, HA-CA hydrogels were able to mediate efficient engraftment of hADSCs into the defect regions. When compared to photopolymerized HA hydrogels, HA-CA hydrogels significantly enhanced hADSC-mediated therapeutic angiogenesis (promoted capillary/arteriole formation, improved vascular perfusion, attenuated ischemic muscle degeneration/fibrosis, and reduced limb amputation) and bone reconstruction (mineralized bone formation, enhanced osteogenic marker expression, and collagen deposition). This study proves the feasibility of using bioinspired HA-CA hydrogels as functional biomaterials for improved tissue regeneration in critical tissue defects.


Assuntos
Tecido Adiposo/citologia , Catecóis/química , Ácido Hialurônico/química , Hidrogéis/química , Neovascularização Fisiológica/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Proteína Morfogenética Óssea 2/metabolismo , Catecóis/farmacologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Traumatismos Craniocerebrais/terapia , Modelos Animais de Doenças , Feminino , Membro Posterior/irrigação sanguínea , Humanos , Ácido Hialurônico/farmacologia , Hidrogéis/farmacologia , Isquemia/terapia , Camundongos Nus , Crânio/efeitos dos fármacos , Crânio/lesões , Alicerces Teciduais/química
11.
J Anat ; 227(1): 10-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26041429

RESUMO

Caffeine adversely affects endochondral ossification during fetal skeletal growth, and results in increased incidence of delayed and abnormal fetal skeletal development. Chronic caffeine intake also decreases growth hormone secretion. Thus, it is conceivable that caffeine may disrupt bone growth during the peripubertal period. This study aimed to investigate the impact of high-caffeine consumption on bone growth throughout puberty. A total of 51 male rats (21 days old) were divided randomly into three groups: a control group and two groups fed caffeine via gavage with 120 and 180 mg kg(-1)  day(-1) for 4 weeks. After death, the final length and weight of leg bones were measured, and the tibia processed for histomorphometric analysis. Caffeine caused a significant decrease in body mass gain. This was accompanied with proportional decreases in lean body mass and body fat. In addition, bone mass and osteogenic activity in vivo were assessed using dual-energy X-ray absorptiometry and (18) F-NaF positron emission tomography. The results showed significant decreases of bone mass and in vivo osteogenic activity in the caffeine-fed groups. Rats fed with caffeine showed a significantly shorter and lighter tibia and femur and the vertebral column compared with controls. In addition, caffeine does not increase the width of the growth plates (GPs), it slows the rate at which the GP closes due to a slower rate of growth. These results demonstrated that caffeine altered osteogenic activity, leading to delayed peripubertal longitudinal bone growth and maturation. Given that osteogenic cells undergo dynamic changes in metabolic activity and that the pubertal growth spurt is mainly stimulated by growth hormone/insulin-like growth factor-1 and sex steroids during pubertal development, caffeine could suppress ossification by interfering with both physiological changes in hormonal secretion and osteogenic activity during this critical period. Further study will be needed to investigate the cellular/molecular mechanism by which caffeine affects osteogenesis using in vitro experimental models.


Assuntos
Desenvolvimento Ósseo/efeitos dos fármacos , Cafeína/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Absorciometria de Fóton , Animais , Peso Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Modelos Animais de Doenças , Fêmur/efeitos dos fármacos , Lâmina de Crescimento/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Osteogênese/efeitos dos fármacos , Tomografia por Emissão de Pósitrons , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Tíbia/efeitos dos fármacos
12.
Eur J Orthop Surg Traumatol ; 25(2): 233-42, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25028335

RESUMO

BACKGROUND: Composite ceramic with polyethylene backing was introduced to enhance the quality of ceramic articulation, but the liner's high rate of ceramic fracture has brought serious concern. In this study, the authors investigated the failure rate of sandwich liner in long-term follow-up patients at single institution. METHODS: In this series, we retrospectively reviewed 134 patients (143 hips), and six patients (6.2%) were found to have liner fracture. They were compared to nonfracture patients to identify the associating factors. General patient characteristics were obtained through review of charts. All patients were implanted with SPH Contact acetabular cup and sandwich liner. Function (Harris hip score) and activity (Devane score) were recorded preoperatively and at final follow-up. Radiologically, inclination and abduction angles were measured for comparison. RESULTS: The study did not show any statistical differences between fracture and nonfracture groups in age, weight or body mass index. Side, type of stem used and radiologic parameters were not also significantly different. The operation had significantly improved function and activity postoperatively in both groups, but no statistical significance was noted between the two groups exception to preoperative Harris hip score. On inspection, retrieved ceramic heads and liners showed substantial metal transfer on their surfaces, and linear wears were evident on the ceramic heads. CONCLUSIONS: Compared to other studies, our series also experienced high rate of sandwich liner fracture. Though its use was generally discontinued, it is worrisome to note that failure rate of the liner will substantially increase over time.


Assuntos
Acetabuloplastia , Cerâmica/efeitos adversos , Prótese de Quadril , Polietileno/efeitos adversos , Falha de Prótese/etiologia , Adolescente , Adulto , Idoso , Artroplastia de Substituição do Tornozelo/efeitos adversos , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Reoperação , Estudos Retrospectivos , Adulto Jovem
13.
Biomacromolecules ; 15(1): 206-18, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24350561

RESUMO

Decellularization of tissues or organs can provide an efficient strategy for preparing functional scaffolds for tissue engineering. Microstructures of native extracellular matrices and their biochemical compositions can be retained in the decellularized matrices, providing tissue-specific microenvironments for efficient tissue regeneration. Here, we report the versatility of liver extracellular matrix (LEM) that can be used for two-dimensional (2D) coating and three-dimensional (3D) hydrogel platforms for culture and transplantation of primary hepatocytes. Collagen type I (Col I) has typically been used for hepatocyte culture and transplantation. In this study, LEM was compared with Col I in terms of biophysical and mechanical characteristics and biological performance for enhancing cell viability, differentiation, and hepatic functions. Surface properties of LEM coating and mechanical properties and gelation kinetics of LEM hydrogel could be manipulated by adjusting the LEM concentration. In addition, LEM hydrogel exhibited improved elastic properties, rapid gelation, and volume maintenance compared to Col I hydrogel. LEM coating significantly improved hepatocyte functions such as albumin secretion and urea synthesis. More interestingly, LEM coating upregulated hepatic gene expression of human adipose-derived stem cells, indicating enhanced hepatic differentiation of these stem cells. The viability and hepatic functions of primary hepatocytes were also significantly improved in LEM hydrogel compared to Col I hydrogel both in vitro and in vivo. Albumin and hepatocyte transcription factor expression was upregulated in hepatocytes transplanted in LEM hydrogels. In conclusion, LEM can provide functional biomaterial platforms for diverse applications in liver tissue engineering by promoting survival and maturation of hepatocytes and hepatic commitment of stem cells. This study demonstrates the feasibility of decellularized matrix for both 2D coating and 3D hydrogel in liver tissue engineering.


Assuntos
Matriz Extracelular/fisiologia , Hidrogéis/química , Fígado/fisiologia , Engenharia Tecidual/métodos , Animais , Matriz Extracelular/química , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/fisiologia , Humanos , Hidrogéis/administração & dosagem , Injeções , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Especificidade por Substrato/efeitos dos fármacos , Especificidade por Substrato/fisiologia
14.
Mater Today Bio ; 25: 100983, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38327977

RESUMO

The use of the FDA-approved osteoinductive growth factor BMP2 is widespread for bone regeneration. However, its clinical application has been hindered by limitations in cell permeability and a short half-life in circulation. To address this issue, we have developed a modified version of BMP2, referred to as Cell Permeable (CP)-BMP2, which possesses improved cell permeability. CP-BMP2 incorporates an advanced macromolecular transduction domain (aMTD) to facilitate transfer across the plasma membrane, a solubilization domain, and recombinant human BMP2. Compared to traditional rhBMP2, CP-BMP2 exhibits enhanced cell permeability, solubility, and bioavailability, and activates Smad phosphorylation through binding to BMP receptor 2. The effectiveness of CP-BMP2 was evaluated in three animal studies focusing on bone regeneration. In the initial study, mice and rabbits with critical-size calvarial defects received subcutaneous (SC) injections of CP-BMP2 and rhBMP2 (7.5 mg/kg, 3 injections per week for 8 weeks).Following 8 weeks of administration, CP-BMP2 demonstrated a remarkable 65 % increase in bone formation in mice when compared to both the vehicle and rhBMP2. Moreover, rabbits exhibited faster bone formation, characterized by a filling pattern originating from the center. In a subsequent study involving injured horses, hind limb bones treated with CP-BMP2 exhibited an 85 % higher bone regeneration rate, as evidenced by Micro-CT results, in contrast to horses treated with the vehicle or rhBMP2 (administered at 150 µg/defect, subcutaneously, once a week for 8 weeks, without a scaffold). These results underscore the potential of CP-BMP2 to facilitate rapid and effective healing. No noticeable adverse effects, such as ectopic bone formation, were observed in any of the studies. Overall, our findings demonstrate that CP-BMP2 holds therapeutic potential as a novel and effective osteogenic agent.

15.
Nat Commun ; 15(1): 5058, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871682

RESUMO

In this study, high-performance organic photodetectors are presented which utilize a pristine chlorinated subphthalocyanine photoactive layer. Optical and optoelectronic analyses indicate that the device photocurrent is primarily generated through direct charge generation within the chlorinated subphthalocyanine layer, rather than exciton separation at layer interfaces. Molecular modelling suggests that this direct charge generation is facilitated by chlorinated subphthalocyanine high octupole moment (-80 DÅ2), which generates a 200 meV shift in molecular energetics. Increasing the thickness of chlorinated subphthalocyanine leads to faster response time, correlated with a decrease in trap density. Notably, photodetectors with a 50 nm thick chlorinated subphthalocyanine photoactive layer exhibit detectivities approaching 1013 Jones, with a dark current below 10-7 A cm-2 up to -5 V. Based on these findings, we conclude that high octupole moment molecular semiconductors are promising materials for high-performance organic photodetectors employing single-component photoactive layer.

16.
Biomacromolecules ; 14(9): 3202-13, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-23941596

RESUMO

Immobilization of osteoinductive molecules, including growth factors or peptides, on polymer scaffolds is critical for improving stem cell-mediated bone tissue engineering. Such molecules provide osteogenesis-stimulating signals for stem cells. Typical methods used for polymeric scaffold modification (e.g., chemical conjugation or physical adsorption), however, have limitations (e.g., multistep, complicated procedures, material denaturation, batch-to-batch inconsistency, and inadequate conjugation) that diminish the overall efficiency of the process. Therefore, in this study, we report a biologically inspired strategy to prepare functional polymer scaffolds that efficiently regulate the osteogenic differentiation of human adipose-derived stem cells (hADSCs). Polymerization of dopamine (DA), a repeated motif observed in mussel adhesive protein, under alkaline pH conditions, allows for coating of a polydopamine (pDA) layer onto polymer scaffolds. Our study demonstrates that predeposition of a pDA layer facilitates highly efficient, simple immobilization of peptides derived from osteogenic growth factor (bone morphogenetic protein-2; BMP-2) on poly(lactic-co-glycolic acid) (PLGA) scaffolds via catechol chemistry. The BMP-2 peptide-immobilized PLGA scaffolds greatly enhanced in vitro osteogenic differentiation and calcium mineralization of hADSCs using either osteogenic medium or nonosteogenic medium. Furthermore, transplantation of hADSCs using pDA-BMP-2-PLGA scaffolds significantly promoted in vivo bone formation in critical-sized calvarial bone defects. Therefore, pDA-mediated catechol functionalization would be a simple and effective method for developing tissue engineering scaffolds exhibiting enhanced osteoinductivity. To the best of our knowledge, this is the first study demonstrating that pDA-mediated surface modification of polymer scaffolds potentiates the regenerative capacity of human stem cells for healing tissue defect in vivo.


Assuntos
Células-Tronco Adultas/fisiologia , Proteína Morfogenética Óssea 2/química , Regeneração Óssea , Indóis/química , Polímeros/química , Tecido Adiposo/citologia , Células-Tronco Adultas/transplante , Sequência de Aminoácidos , Animais , Proteína Morfogenética Óssea 2/farmacologia , Diferenciação Celular , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Colágeno/metabolismo , Feminino , Humanos , Proteínas Imobilizadas/química , Proteínas Imobilizadas/farmacologia , Ácido Láctico/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dados de Sequência Molecular , Osteogênese , Osteopontina/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Radiografia , Medicina Regenerativa , Crânio/irrigação sanguínea , Crânio/diagnóstico por imagem , Crânio/metabolismo , Propriedades de Superfície
17.
Biomacromolecules ; 14(6): 2004-13, 2013 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-23639096

RESUMO

Alginate hydrogels are for various biomedical applications including tissue engineering, cell therapy, and drug delivery. However, it is not easy to control swelling or viscoelastic and biophysical properties of alginate hydrogels prepared by conventional cross-linking methods (ionic interaction using divalent cations). In this study, we describe a bioinspired approach for preparing divalent ion-free alginate hydrogels that exhibit tunable physical and mechanical properties and improved biocompatibility due to the absence of cations in the gel matrices. We conjugated dopamine, a minimalized adhesive motif found in the holdfast pads of mussels, to alginate backbones (alginate-catechol) and the tethered catechols underwent oxidative cross-linking. This resulted in divalent cation-free alginate hydrogels. The swelling ratios and moduli of the alginate-catechol hydrogels are readily tunable, which is difficult to achieve in ionic bond-based alginate hydrogels. Furthermore, alginate-catechol hydrogels enhanced the survival of various human primary cells including stem cells in the three-dimensional gel matrix, indicating that intrinsic cytotoxicity caused by divalent cations becomes negligible when employing catechol oxidation for alginate cross-linking. The inflammatory response in vivo was also significantly attenuated compared to conventional alginate hydrogels with calcium cross-linking. This biomimetic approach for the preparation of alginate hydrogels may provide a novel platform technology to develop tunable, functional, biocompatible, three-dimensional scaffolds for tissue engineering and cell therapy.


Assuntos
Alginatos/química , Materiais Biocompatíveis , Cálcio/química , Hidrogéis , Animais , Células Cultivadas , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura
18.
BMB Rep ; 56(5): 275-286, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37081756

RESUMO

Cancer immunotherapy has been acknowledged as a new paradigm for cancer treatment, with notable therapeutic effects on certain cancer types. Despite their significant potential, clinical studies over the past decade have revealed that cancer immunotherapy has low response rates in the majority of solid tumors. One of the key causes for poor responses is known to be the relatively low immunogenicity of solid tumors. Because most solid tumors are immune desert 'cold tumors' with antitumor immunity blocked from the onset of innate immunity, combination therapies that combine validated T-based therapies with approaches that can increase tumor-immunogenicity are being considered as relevant therapeutic options. This review paper focuses on immunogenic cell death (ICD) as a way of enhancing immunogenicity in tumor tissues. We will thoroughly review how ICDs such as necroptosis, pyroptosis, and ferroptosis can improve anti-tumor immunity and outline clinical trials targeting ICD. Finally, we will discuss the potential of ICD inducers. as an adjuvant for cancer immunotherapy.[BMB Reports 2023; 56(5): 275-286].


Assuntos
Antineoplásicos , Neoplasias , Humanos , Morte Celular , Morte Celular Imunogênica , Imunoterapia , Antineoplásicos/farmacologia
19.
Am J Cancer Res ; 13(2): 452-463, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36895970

RESUMO

Double hit diffuse large B-cell lymphoma (DLBCL) with rearrangement and overexpression of both c-Myc and Bcl-2 responds poorly to standard R-CHOP therapy. In a recent phase I study, Venetoclax (ABT-199) targeting Bcl-2 also exhibited disappointing response rates in patients with relapsed/refractory DLBCL, suggesting that targeting only Bcl-2 is not sufficient for achieving successful efficacy due to the concurrent oncogenic function of c-Myc expression and drug resistance following an increase in Mcl-1. Therefore, co-targeting c-Myc and Mcl-1 could be a key combinatorial strategy to enhance the efficacy of Venetoclax. In this study, BR101801 a novel drug for DLBCL, effectively inhibited DLBCL cell growth/proliferation, induced cell cycle arrest, and markedly inhibited G0/G1 arrest. The apoptotic effect of BR101801 was also observed by increased Cytochrome C, cleaved PARP, and Annexin V-positive cell populations. This anti-cancer effect of BR101801 was confirmed in animal models, where it effectively inhibited tumor growth by reducing the expression of both c-Myc and Mcl-1. Furthermore, BR101801 exhibited a significant synergistic antitumor effect even in late xenograft models when combined with Venetoclax. Our data strongly suggest that c-Myc/Bcl-2/Mcl-1 triple targeting through a combination of BR101801 and Venetoclax could be a potential clinical option for double-hit DLBCL.

20.
Sci Rep ; 12(1): 19862, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36400842

RESUMO

In this study, the effect of intake manifold geometry on cylinder-to-cylinder variation was investigated considering the volumetric efficiency, early tumble development, turbulent kinetic energy, and spark plug gap velocity using computational fluid dynamic program, CONVERGE v2.4. The simulation model was validated based on the PIV experiment in the cylinder and Mie-scattering experiment of intake manifold, and its results agreed well with the experiment results. The curved intake manifold and straight manifold were compared. As a result, it was advantageous for cylinder-to-cylinder variation in the straight intake manifold compared to the curved intake manifold in perspective of volumetric efficiency which were a maximum deviation of 1.7% in curved manifold and 0.6% in straight manifold. And the straight manifold had an effect of the strengthening the in-cylinder flow, so that the turbulent kinetic energy near TDC was increased to maximum 11% than curved manifold. And considering the effect of manifold curve radius on in-cylinder flow intensity in straight manifold, with increasing engine speed, the in-cylinder flow intensified during compression with decreasing the intake manifold radius due to the short distance between manifold inlet and port. Especially at 2000 rpm, the tumble ratio increased 55% at intake manifold radius of 10 cm than of 7 cm at bTDC 280 deg. Therefore, for the purpose of enhancing the in-cylinder flow near spark plug timing, shortened distance between intake manifold inlet and port and increasing the manifold radius is required.

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