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1.
J Mater Sci Mater Med ; 30(9): 109, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31535210

RESUMO

Treatment of an open abdomen (OA) wound combined with an intestinal fistula is a challenge in the clinic. Here, inspired by the antibacterial activity of graphene (G) and its derivatives, we present a hybrid patch based on the ability of graphene and polycaprolactone (PCL) to kill bacteria and save the cells in a wound. Benefiting from the antibacterial ability of graphene oxide (GO), cells could survive in the presence of bacteria. With the increased ability to protect cells, this patch accelerated wound healing in an OA and intestinal fistula wound model. Additionally, the sub-acute toxicity score showed no extra damage to organs. In conclusion, the employment of the hybrid material for an OA and an intestinal fistula wound healing is encouraging. A hybrid patch based on graphene oxide and polycaprolactone electrospun was generated for open abdomen and fistula wound. The application of the hybrid patch could save the cells from bacteria which contribute to accelerating wound healing.


Assuntos
Grafite/química , Grafite/farmacologia , Fístula Intestinal/prevenção & controle , Técnicas de Abdome Aberto/instrumentação , Telas Cirúrgicas , Cicatrização/fisiologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Masculino , Teste de Materiais , Nanofibras/química , Técnicas de Abdome Aberto/métodos , Ratos , Ratos Sprague-Dawley , Cicatrização/efeitos dos fármacos
2.
BMC Infect Dis ; 17(1): 637, 2017 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-28934938

RESUMO

BACKGROUND: The purpose of this study was to determine the shifting trends in bacteriology and antimicrobial resistance of infectious specimens isolated from gastrointestinal (GI) fistula patients over eight years in China. METHODS: We retrospectively reviewed the microbial records of intra-abdominal specimens at a teaching hospital from 2008 to 2015. Study period was divided into the first half (2008-2011) and the second half (2012-2015). All isolates underwent antibiotic susceptibility testing by the micro dilution method. RESULTS: A total of 874 intra-abdominal isolates were consecutively collected from 502 GI fistula patients (mean age, 46.5 years, 71.1% male) during the study period. Patients in the second study period (2012-2015) were older (>65 years) and more likely to have experienced cancer. Over the entire study period, most infections were caused by E. coli (24.2%) and K. pneumonia (14.1%). There was a significant decrease in the proportion E. coli isolates that were extended- spectrum beta-lactamase (ESBL)-positive (P = 0.026). The proportion of E. coli resistant to imipenem increased from 14.3% in 2008-2011 to 25.9% in 2012-2015 (P = 0.037). Imipenem resistance prevalence was higher in ESBL-negative bacteria than ESBL-positive bacteria for both E. coli and K. pneumonia (P < 0.001). In Enterococcus, significant increase in resistance to ampicillin (P = 0.01) and moxifloxacin (P = 0.02) over time were observed. In Staphylococcus and fungi, rates of antibiotic resistance did not significantly change over the study period. CONCLUSIONS: Gram-negative bacteria predominated as causative agents of intra-abdominal infections in GI fistula patients, and there was an increase in levels of resistance to certain antibiotics, particularly carbapenems. Infection control and source control are important tools available to surgeons to prevent the emergence of antibiotic-resistant pathogens.


Assuntos
Fístula do Sistema Digestório/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções Intra-Abdominais/microbiologia , Adolescente , Adulto , Idoso , Ampicilina/farmacologia , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , China/epidemiologia , Fístula do Sistema Digestório/complicações , Escherichia coli/efeitos dos fármacos , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Negativas/patogenicidade , Humanos , Imipenem/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem , beta-Lactamases/metabolismo
3.
Adv Sci (Weinh) ; 11(17): e2308051, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38350727

RESUMO

Molecular engineering of drug delivering platforms to provide collaborative biological effects with loaded drugs is of great medical significance. Herein, cannabinoid receptor 1 (CB1)- and reactive oxygen species (ROS)-targeting electrosprayed microspheres (MSs) are fabricated by loading with the CB1 agonist arachidonoyl 2'-chloroethylamide (ACEA) and producing ROS in a photoresponsive manner. The synergistic anti-tumor effects of ACEA and ROS released from the MSs are assessed. ACEA inhibits epidermal growth factor receptor signaling and altered tumor microenvironment (TME) by activating CB1 to induce tumor cell death. The MSs are composed of glycidyl methacrylate-conjugated xanthan gum (XGMA) and Fe3+, which form dual molecular networks based on a Fe3+-(COO-)3 network and a C═C addition reaction network. Interestingly, the Fe3+-(COO-)3 network can be disassembled instantly under the conditions of lactate sodium and ultraviolet exposure, and the disassembly is accompanied by massive ROS production, which directly injures tumor cells. Meanwhile, the transition of dual networks to a single network boosts the ACEA release. Together, the activities of the ACEA and MSs promote immunogenic tumor cell death and create a tumor-suppressive TME by increasing M1-like tumor-associated macrophages and CD8+ T cells. In summation, this study demonstrates strong prospects of improving anti-tumor effects of drug delivering platforms through molecular design.


Assuntos
Antineoplásicos , Ácidos Araquidônicos , Agonistas de Receptores de Canabinoides , Neoplasias Colorretais , Imunoterapia , Receptor CB1 de Canabinoide , Microambiente Tumoral , Hidrogéis/administração & dosagem , Microesferas , Imunoterapia/métodos , Receptor CB1 de Canabinoide/agonistas , Espécies Reativas de Oxigênio/metabolismo , Agonistas de Receptores de Canabinoides/administração & dosagem , Agonistas de Receptores de Canabinoides/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Receptores ErbB/antagonistas & inibidores , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Sistemas de Liberação de Medicamentos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/imunologia , Humanos , Linhagem Celular Tumoral , Raios Ultravioleta , Ácidos Araquidônicos/administração & dosagem , Ácidos Araquidônicos/farmacologia , Polissacarídeos Bacterianos/química , Compostos de Epóxi/química , Metacrilatos/química , Desenho de Fármacos
4.
Animal Model Exp Med ; 7(4): 562-569, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38158631

RESUMO

INTRODUCTION: This study aimed to establish an animal model of open abdomen (OA) through temporary abdominal closure via different techniques. METHODS: Adult male Sprague-Dawley rats were randomly divided into three groups: group A (OA with polypropylene mesh alone); group B (OA with polypropylene mesh combined with a patch); and group C (OA with polypropylene mesh and a sutured patch). Vital signs, pathophysiological changes, and survival rates were closely monitored in the rats for 7 days after surgery. Abdominal X-rays and histopathological examinations were performed to assess abdominal organ changes and wound healing. RESULTS: The results showed no significant difference in mortality rates among the three groups (p > 0.05). However, rats in group B exhibited superior overall condition, cleaner wounds, and a higher rate of wound healing compared to the other groups (p < 0.05). Abdominal X-rays indicated that varying degrees of distal intestinal obstruction in all groups. Histopathological examinations revealed fibrous hyperplasia, inflammatory cell infiltration, neovascularization, and collagen deposition in all groups. Group B demonstrated enhanced granulation tissue generation, neovascularization, and collagen deposition compared to the other groups (p < 0.05). CONCLUSIONS: Polypropylene mesh combined with patches is the most suitable method for establishing an animal model of OA. This model successfully replicated the pathological and physiological changes in postoperative patients with OA, specifically the progress of abdominal skin wound healing. It provides a practical and reliable animal model for OA research.


Assuntos
Modelos Animais de Doenças , Ratos Sprague-Dawley , Telas Cirúrgicas , Cicatrização , Animais , Masculino , Ratos , Polipropilenos , Técnicas de Abdome Aberto , Abdome/cirurgia , Abdome/diagnóstico por imagem
5.
ACS Appl Mater Interfaces ; 16(22): 28147-28161, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38783481

RESUMO

Nonhealing infectious wounds, characterized by bacterial colonization, wound microenvironment destruction, and shape complexity, present an intractable problem in clinical practice. Inspired by LEGOs, building-block toys that can be assembled into desired shapes, we proposed the use of electrospray nano-micro composite sodium alginate (SA) microspheres with antibacterial and angiogenic properties to fill irregularly shaped wounds instantly. Specifically, porous poly(lactic-co-glycolic acid) (PLGA) microspheres (MSs) encapsulating basic fibroblast growth factor (bFGF) were produced by a water-in-oil-in-water double-emulsion method. Then, bFGF@MSs were blended with the SA solution containing ZIF-8 nanoparticles. The resultant solution was electrosprayed to obtain nano-micro composite microspheres (bFGF@MS/ZIF-8@SAMSs). The composite MSs' size could be regulated by PLGA MS mass proportion and electrospray voltage. Moreover, bFGF, a potent angiogenic agent, and ZIF-8, bactericidal nanoparticles, were found to release from bFGF@MS/ZIF-8@SAMSs in a controlled and sustainable manner, which promoted cell proliferation, migration, and tube formation and killed bacteria. Through experimentation on rat models, bFGF@MS/ZIF-8@SAMSs were revealed to adapt to wound shapes and accelerate infected wound healing because of the synergistic effects of antibacterial and angiogenic abilities. In summation, this study developed a feasible approach to prepare bioactive nano-micro MSs as building blocks that can fill irregularly shaped infected wounds and improve healing.


Assuntos
Alginatos , Antibacterianos , Fator 2 de Crescimento de Fibroblastos , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Cicatrização , Alginatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Ratos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Fator 2 de Crescimento de Fibroblastos/química , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos , Masculino , Escherichia coli/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Células Endoteliais da Veia Umbilical Humana , Testes de Sensibilidade Microbiana , Proliferação de Células/efeitos dos fármacos , Ácido Glucurônico/química , Ácido Glucurônico/farmacologia
6.
Biomater Res ; 28: 0031, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38845842

RESUMO

The abdominal wall plays a crucial role in safeguarding the internal organs of the body, serving as an essential protective barrier. Defects in the abdominal wall are common due to surgery, infection, or trauma. Complex defects have limited self-healing capacity and require external intervention. Traditional treatments have drawbacks, and biomaterials have not fully achieved the desired outcomes. Hydrogel has emerged as a promising strategy that is extensively studied and applied in promoting tissue regeneration by filling or repairing damaged tissue due to its unique properties. This review summarizes the five prominent properties and advances in using hydrogels to enhance the healing and repair of abdominal wall defects: (a) good biocompatibility with host tissues that reduces adverse reactions and immune responses while supporting cell adhesion migration proliferation; (b) tunable mechanical properties matching those of the abdominal wall that adapt to normal movement deformations while reducing tissue stress, thereby influencing regulating cell behavior tissue regeneration; (c) drug carriers continuously delivering drugs and bioactive molecules to sites optimizing healing processes enhancing tissue regeneration; (d) promotion of cell interactions by simulating hydrated extracellular matrix environments, providing physical support, space, and cues for cell migration, adhesion, and proliferation; (e) easy manipulation and application in surgical procedures, allowing precise placement and close adhesion to the defective abdominal wall, providing mechanical support. Additionally, the advances of hydrogels for repairing defects in the abdominal wall are also mentioned. Finally, an overview is provided on the current obstacles and constraints faced by hydrogels, along with potential prospects in the repair of abdominal wall defects.

7.
Biomater Sci ; 12(4): 837-862, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38196386

RESUMO

Inflammatory bowel disease (IBD) is a chronic disorder that affects millions of individuals worldwide. However, current drug therapies for IBD are plagued by significant side effects, low efficacy, and poor patient compliance. Consequently, there is an urgent need for novel therapeutic approaches to alleviate IBD. Hydrogels, three-dimensional networks of hydrophilic polymers with the ability to swell and retain water, have emerged as promising materials for drug delivery in the treatment of IBD due to their biocompatibility, tunability, and responsiveness to various stimuli. In this review, we summarize recent advancements in hydrogel-based drug delivery systems for the treatment of IBD. We first identify three pathophysiological alterations that need to be addressed in the current treatment of IBD: damage to the intestinal mucosal barrier, dysbiosis of intestinal flora, and activation of inflammatory signaling pathways leading to disequilibrium within the intestines. Subsequently, we discuss in depth the processes required to prepare hydrogel drug delivery systems, from the selection of hydrogel materials, types of drugs to be loaded, methods of drug loading and drug release mechanisms to key points in the preparation of hydrogel drug delivery systems. Additionally, we highlight the progress and impact of the hydrogel-based drug delivery system in IBD treatment through regulation of physical barrier immune responses, promotion of mucosal repair, and improvement of gut microbiota. In conclusion, we analyze the challenges of hydrogel-based drug delivery systems in clinical applications for IBD treatment, and propose potential solutions from our perspective.


Assuntos
Hidrogéis , Doenças Inflamatórias Intestinais , Humanos , Hidrogéis/farmacologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Intestinos , Mucosa Intestinal/metabolismo , Sistemas de Liberação de Medicamentos/métodos
8.
ACS Appl Mater Interfaces ; 16(23): 30430-30442, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38814614

RESUMO

Patients with open abdominal (OA) wounds have a mortality risk of up to 30%, and the resulting disabilities would have profound effects on patients. Here, we present a novel double-sided adhesive tape developed for the management of OA wounds. The tape features an asymmetrical structure and employs an acellular dermal matrix (ADM) with asymmetric wettability as a scaffold. It is constructed by integrating a tissue-adhesive hydrogel composed of polydopamine (pDA), quaternary ammonium chitosan (QCS), and acrylic acid cross-linking onto the bottom side of the ADM. Following surface modification with pDA, the ADM would exhibit characteristics resistant to bacterial adhesion. Furthermore, the presence of a developed hydrogel ensures that the tape not only possesses tissue adhesiveness and noninvasive peelability but also effectively mitigates damage caused by oxidative stress. Besides, the ADM inherits the strength of the skin, imparting high burst pressure tolerance to the tape. Based on these remarkable attributes, we demonstrate that this double-sided (D-S) tape facilitates the repair of OA wounds, mitigates damage to exposed intestinal tubes, and reduces the risk of intestinal fistulae and complications. Additionally, the D-S tape is equally applicable to treating other abdominal injuries, such as gastric perforations. It effectively seals the perforation, promotes injury repair, and prevents the formation of postoperative adhesions. These notable features indicate that the presented double-sided tape holds significant potential value in the biomedical field.


Assuntos
Traumatismos Abdominais , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Quitosana/química , Quitosana/farmacologia , Camundongos , Polímeros/química , Polímeros/farmacologia , Humanos , Indóis/química , Indóis/farmacologia , Cicatrização/efeitos dos fármacos , Pressão , Masculino , Ratos
9.
Carbohydr Polym ; 326: 121508, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142061

RESUMO

The clinical treatment of enterocutaneous fistula is challenging and causes significant patient discomfort. Fibrin gel can be used to seal tubular enterocutaneous fistulas, but it has low strength and poor digestion resistance. Based on in situ bioprinting and the anti-digestive properties of xanthan gum (XG), we used carboxymethyl chitosan (CMC) and xanthan gum modified by grafted glycidyl methacrylate (GMA) and aldehyde (GCX) as the ink to print a double network hydrogel that exhibited high strength and an excellent anti-digestive performance. In addition, in vitro studies confirmed the biocompatibility, degradability, and self-healing of hydrogels. In our rabbit tubular enterocutaneous fistula model, the in situ printed hydrogel resisted corrosion due to the intestinal fluid and acted as a scaffold for intestinal mucosal cells to proliferate on its surface. To summarize, in situ bioprinting GCX/CMC double network hydrogel can effectively block tubular enterocutaneous fistulas and provide a stable scaffold for intestinal mucosal regeneration.


Assuntos
Bioimpressão , Fístula Intestinal , Animais , Humanos , Coelhos , Hidrogéis , Polissacarídeos Bacterianos/uso terapêutico
10.
Int J Bioprint ; 9(5): 764, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457930

RESUMO

Biomedical implants have recently shown excellent application potential in tissue repair and replacement. Applying three-dimensional (3D) printing to implant scaffold fabrication can help to address individual needs more precisely. Fourdimensional (4D) printing emerges rapidly based on the development of shape-responsive materials and design methods, which makes the production of dynamic functional implants possible. Smart implants can be pre-designed to respond to endogenous or exogenous stimuli and perform seamless integration with regular/ irregular tissue defects, defect-luminal organs, or curved structures via programmed shape morphing. At the same time, they offer great advantages in minimally invasive surgery due to the small-to-large volume transition. In addition, 4D-printed cellular scaffolds can generate extracellular matrix (ECM)-mimetic structures that interact with the contacting cells, expanding the possible sources of tissue/organ grafts and substitutes. This review summarizes the typical technologies and materials of 4D-printed scaffolds, and the programming designs and applications of these scaffolds are further highlighted. Finally, we propose the prospects and outlook of 4D-printed shape-morphing implants.

11.
ACS Appl Mater Interfaces ; 15(8): 10506-10519, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36800308

RESUMO

A structurally stable and antibacterial biomaterial used for temporary cranioplasty with guided bone regeneration (GBR) effects is an urgent clinical requirement. Herein, we reported the design of a biomimetic Ag/bacterial cellulose/hydroxyapatite (Ag/BC@HAp) hydrogel mesh with a double-sided functionalized structure, in which one layer was dense and covered with Ag nanoparticles and the other layer was porous and anchored with hydroxyapatite (HAp) via mineralization for different durations. Such a double-sided functionalized design endowed the hydrogel with distinguished antibacterial activities for inhibiting potential infections and GBR effects that could prevent endothelial cells and fibroblasts from migrating to a defected area and meanwhile show biocompatibility to MC3T3-E1 preosteoblasts. Furthermore, it was found from in vivo experimental results that the Ag/BC@HAp hydrogel with 7-day mineralization achieved optimal GBR effects by improving barrier functions toward these undesired cells. Moreover, this BC-based hydrogel mesh showed an extremely low swelling ratio and strong mechanical strength, which facilitated the protection of soft brain tissues without gaining the risk of intracranial pressure increase. In a word, this study offers a new approach to double-sided functionalized hydrogels and provides effective and safe biomaterials used for temporary cranioplasty with antibacterial abilities and GBR effects.


Assuntos
Durapatita , Nanopartículas Metálicas , Durapatita/química , Prata , Hidrogéis/química , Celulose/química , Biomimética , Células Endoteliais , Telas Cirúrgicas , Materiais Biocompatíveis , Antibacterianos
12.
Adv Healthc Mater ; 12(29): e2301313, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37220875

RESUMO

The problems of step effects, supporting material waste, and conflict between flexibility and toughness for 3D printed intestinal fistula stents are not yet resolved. Herein, the fabrication of a support-free segmental stent with two types of thermoplastic polyurethane (TPU) using a homemade multi-axis and multi-material conformal printer guided with advanced whole model path planning is demonstrated. One type of TPU segment is soft to increase elasticity, and the other is used to achieve toughness. Owing to advancements in stent design and printing, the obtained stents present three unprecedented properties compared to previous three-axis printed stents: i) Overcoming step effects; ii) Presenting comparable axial flexibility to a stent made of a single soft TPU 87A material, thus increasing the feasibility of implantation; and iii) Showing equivalent radial toughness to a stent made of a single hard TPU 95A material. Hence, the stent can resist the intestinal contractive force and maintain intestinal continuity and patency. Through implanting such stents to the rabbit intestinal fistula models, therapeutic mechanisms of reducing fistula output and improving nutritional states and intestinal flora abundance are revealed. Overall, this study develops a creative and versatile method to improve the poor quality and mechanical properties of medical stents.


Assuntos
Fístula Intestinal , Stents , Animais , Coelhos , Poliuretanos , Fenômenos Mecânicos , Impressão Tridimensional
13.
Int J Bioprint ; 9(3): 682, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37273990

RESUMO

Peritoneal adhesion is a critical issue after abdominal surgery. Cell-based methods for preventing peritoneal adhesion have not yet been fully investigated. Here, we constructed a highly biomimetic peritoneal scaffold by seeding mesothelial cells, the natural physiological barrier of the peritoneum, onto a melt electrowriting-printed scaffold. The scaffolds with the microfibers crossed at different angles (30°, 60°, and 90°) were screened based on mesothelial cell proliferation and orientation. Thirty degrees were more suitable for improving proliferation of mesothelial cells and cell growth in a single direction; therefore, the 30° peritoneal scaffold could better mimic the physiological structure of native peritoneum. Mechanistically, such a peritoneal scaffold was able to act as a barrier to prevent peritoneal resident macrophages from migrating to the site of the peritoneal lesion. In vivo mesothelial cell tracking using lentivirus technology confirmed that the peritoneal scaffold, compared to the scaffold without mesothelial cells, could prevent peritoneal adhesion and was directly involved in the repair of injured peritoneum. This study suggests that the peritoneal scaffolds can potentially prevent peritoneal adhesion, offering a new approach for clinical treatment.

14.
Bioact Mater ; 30: 1-14, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37534235

RESUMO

Increasing evidence demonstrates that mammals have different reactions to hypoxia with varied oxygen dynamic patterns. It takes ∼24 h for tri-gas incubator to achieve steady cell hypoxia, which fails to recapitulate ultrafast oxygen dynamics of intestinal ischemia/reperfusion (IR) injury. Inspired from the structure of native intestinal villi, we engineered an intestinal organoid chip embedded with engineered artificial microvessels based on co-axial microfluidic technology by using pH-responsive ZIF-8/sodium alginate scaffold. The chip was featured on: (i) eight times the oxygen exchange efficiency compared with the conventional device, tri-gas incubator, (ii) implantation of intestinal organoid reproducing all types of intestinal epithelial cells, and (iii) bio-responsiveness to hypoxia and reoxygenation (HR) by presenting metabolism disorder, inflammatory reaction, and cell apoptosis. Strikingly, it was found for the first time that Olfactomedin 4 (Olfm4) was the most significantly down-regulated gene under a rapid HR condition by sequencing the RNA from the organoids. Mechanistically, OLFM4 played protective functions on HR-induced cell inflammation and tissue damage by inhibiting the NF-kappa B signaling activation, thus it could be used as a therapeutic target. Altogether, this study overcomes the issue of mismatched oxygen dynamics between in vitro and in vivo, and sets an example of next-generation multisystem-interactive organoid chip for finding precise therapeutic targets of IR injury.

15.
Bioeng Transl Med ; 8(1): e10327, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36684067

RESUMO

Organoids hold inestimable therapeutic potential in regenerative medicine and are increasingly serving as an in vitro research platform. Still, their expanding applications are critically restricted by the canonical culture matrix and system. Synthesis of a suitable bioink of bioactivity, biosecurity, tunable stiffness, and printability to replace conventional matrices and fabricate customized culture systems remains challenging. Here, we envisaged a novel bioink formulation based on decellularized extracellular matrix (dECM) from porcine small intestinal submucosa for organoids bioprinting, which provides intestinal stem cells (ISCs) with niche-specific ECM content and biomimetic microstructure. Intestinal organoids cultured in the fabricated bioink exhibited robust generation as well as a distinct differentiation pattern and transcriptomic signature. This bioink established a new co-culture system able to study interaction between epithelial homeostasis and submucosal cells and promote organoids maturation after transplantation into the mesentery of immune-deficient NODSCID-gamma (NSG) mice. In summary, the development of such photo-responsive bioink has the potential to replace tumor-derived Matrigel and facilitate the application of organoids in translational medicine and disease modeling.

16.
Nat Commun ; 14(1): 7856, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030636

RESUMO

High glucose-induced vascular endothelial injury is a major pathological factor involved in non-healing diabetic wounds. To interrupt this pathological process, we design an all-peptide printable hydrogel platform based on highly efficient and precise one-step click chemistry of thiolated γ-polyglutamic acid, glycidyl methacrylate-conjugated γ-polyglutamic acid, and thiolated arginine-glycine-aspartate sequences. Vascular endothelial growth factor 165-overexpressed human umbilical vein endothelial cells are printed using this platform, hence fabricating a living material with high cell viability and precise cell spatial distribution control. This cell-laden hydrogel platform accelerates the diabetic wound healing of rats based on the unabated vascular endothelial growth factor 165 release, which promotes angiogenesis and alleviates damages on vascular endothelial mitochondria, thereby reducing tissue hypoxia, downregulating inflammation, and facilitating extracellular matrix remodeling. Together, this study offers a promising strategy for fabricating tissue-friendly, high-efficient, and accurate 3D printed all-peptide hydrogel platform for cell delivery and self-renewable growth factor therapy.


Assuntos
Diabetes Mellitus , Hidrogéis , Humanos , Ratos , Animais , Hidrogéis/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ácido Poliglutâmico , Química Click , Cicatrização/fisiologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Diabetes Mellitus/patologia , Impressão Tridimensional
17.
J Mater Chem B ; 10(6): 978-979, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35098287

RESUMO

Correction for 'Engineering an adhesive based on photosensitive polymer hydrogels and silver nanoparticles for wound healing' by Qinqing Tang et al., J. Mater. Chem. B, 2020, 8, 5756-5764, DOI: 10.1039/d0tb00726a.

18.
Mater Today Bio ; 16: 100363, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35898440

RESUMO

Recently, four-dimensional (4D) shape-morphing structures, which can dynamically change shape over time, have attracted much attention in biomedical manufacturing. The 4D printing has the capacity to fabricate dynamic construction conforming to the natural bending of biological tissues, superior to other manufacturing techniques. In this study, we presented a multi-responsive, flexible, and biocompatible 4D-printed bilayer hydrogel based on acrylamide-acrylic acid/cellulose nanocrystal (AAm-AAc/CNC) network. The first layer was first stretched and then formed reversible coordination with Fe3+ to maintain this pre-stretched length; it was later combined with a second layer. The deformation process was actuated by the reduction of Fe3+ to Fe2+ in the first layer which restored it to its initial length. The deformation condition was to immerse the 4D construct in sodium lactate (LA-Na) and then expose it to ultraviolet (UV) light until maximal deformation was realized. The bending degree of this 4D construct can be programmed by modifying the pre-stretched lengths of the first layer. We explored various deformation steps in simple and complex constructs to verify that the 4D bilayer hydrogel can mimic the curved morphology of the intestines. The bilayer hydrogel can also curve in deionized water due to anisotropic volume change yet the response time and maximum bending degree was inferior to deformation in LA-Na and UV light. Finally, we made a 4D-printed bilayer hydrogel stent to test its closure effect for enteroatmospheric fistulas (EAFs) in vitro and in vivo. The results illustrate that the hydrogel plays a role in the temporary closure of EAFs. This study offers an effective method to produce curved structures and expands the potential applications of 4D printing in biomedical fields.

19.
Adv Healthc Mater ; 11(23): e2201878, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36121733

RESUMO

Wound healing is a significant problem in clinical management. Various functional dressings are studied to promote wound healing through biochemical factors. They are generally expensive, complex to fabricate, and may adversely affect the wound. Mechanical forces are the critical regulators of tissue repair. Although contraction is shown to promote wound healing, the underlying mechanisms are not fully understood. In this study, a novel adhesive temperature-sensitive mechanically active hydrogel with a simple and inexpensive preparation process is developed. The dressing is able to adhere to the wound surface and actively contract the wound in response to body temperature. This mechanical contraction enhances the proliferative activity of basal cells, reduces the inflammatory response of the wound, and promotes wound healing. Furthermore, RNA-seq clarifies how the gene regulatory network is regulated by contraction. Finally, using pharmacological inhibitors, YAP and MEK are identified as the key signaling molecules for contraction-mediated tissue healing in vivo.


Assuntos
Hidrogéis , Hidrogéis/farmacologia
20.
J Biomed Nanotechnol ; 18(3): 796-806, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35715900

RESUMO

The novel multifunctional electrospun textiles were fabricated by incorporating sheet-like kaolinite and silver nanoparticles (AgNps) into a polyurethane (PU) textile by using electrostatic spinning to promote wound-healing process. Threedimensional network of PU electrospun textiles offered an appropriate framework for loading kaolinite nanosheets and AgNps. Moreover, the kaolinite nanosheets healed bleeding wounds by accelerating plasma absorption, increasing blood cell concentrations, and stimulating coagulation factors. Furthermore, the AgNps killed microbes by destroying the cell membrane, while the deleterious effects were controlled by incorporation into the electrospun textile. The therapeutic effects of multifunctional electrospun textile in treating full-thickness abdominal wall defect were explored. The wound healing process could be accelerated via the textile by restoring the abdominal physiological environment, reducing the inflammatory response, and promoting collagen deposition, angiogenesis, and epithelization.


Assuntos
Nanopartículas Metálicas , Prata , Antibacterianos/farmacologia , Caulim/farmacologia , Nanopartículas Metálicas/uso terapêutico , Poliuretanos/farmacologia , Prata/farmacologia , Têxteis , Cicatrização
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