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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(6): 896-900, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31880124

RESUMO

OBJECTIVE: Methoxy poly (ethylene glycol)-poly (lactic acid) (mPEG-PDLLA) was used to increase water solubility of netupitant, thus to provide the experimental basis for development of the injection of netupitant. METHODS: Film hydration method was ultilized to prepare the netupitant-loaded mPEG-PDLLA nanoparticles (NT/mPEG-PDLLA-NPs). The preparation formulation and technology were optimized based on the single factor tests by investigating the effect of netupitant/mPEG-PDLLA mass ratio (m/m), filming temperature and time on the mean particle diameters and loading capacities. The size distributions and Zeta potentials of NT/mPEG-PDLLA-NPs were investigated using dynamic light scattering analysis, and the morphology was observed under the transmission electron microscope (TEM). The cytotoxicity of NT/mPEG-PDLLA-NPs evaluated by MTT method. RESULTS: The optimal NT/mPEG-PDLLA-NPs were achieved at the netupitant/mPEG-PDLLA mass ratio of 1/6 with filming temperature at 55 ℃ and filming time for 30 min. The resulting NT/mPEG-PDLLA-NPs displayed an opalescent and translucent appearance, with a high loading capacity of 14% and netupitant concentration of 10 mg/mL. NT/mPEG-PDLLA-NPs showed a spherical morphology, with a mean diameter of 58 nm and a nearly neutral Zeta potential of -0.29 mV. The NT/mPEG-PDLLA-NPs showed a cytotoxicity similar to free NT. CONCLUSION: Netupitant was successfully loaded into mPEG-PDLLA-NPs to significantly increased the water solubility, thus providing the experimental foundation for the further development of injection of netupitant.


Assuntos
Nanopartículas , Portadores de Fármacos , Polietilenoglicóis , Piridinas , Solubilidade
2.
Int J Cancer ; 142(10): 2094-2105, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29277889

RESUMO

Metastasis is the primary cause of death for most cancer patients. Hematogenous arrest of circulating tumor cells (CTCs) is an essential prerequisite for metastases formation. Using transparent transgenic zebrafish (kdrl:eGFP; Casper), together with resonant laser scanning confocal microscopy, we tracked the fate of CTCs in vivo in the blood circulation for days. We found the intra-capillary morphology-switch (ICMS) of individual CTCs from strip to sphere was necessary for their intravascular arrests. Further genetic and pharmacological inhibition experiments indicated that the RhoA signaling was necessary for ICMS and the arrest of CTCs. At last, we demonstrated that early treatment by a clinically approved RhoA/ROCK inhibitor, Fasudil, could efficiently inhibit the initial arrest of individual CTCs and reduce the incidence of tumor metastasis in both zebrafish and mouse models. These results together indicate that RhoA-stimulated ICMS represents a mechanism for the arrest of individual CTCs, providing a potential target for future treatments of hematogenous metastatic disease.


Assuntos
Capilares/patologia , Neoplasias Experimentais/patologia , Células Neoplásicas Circulantes/patologia , Proteína rhoA de Ligação ao GTP/metabolismo , Citoesqueleto de Actina , Animais , Animais Geneticamente Modificados , Capilares/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Neoplasias Experimentais/metabolismo , Células Neoplásicas Circulantes/metabolismo , Peixe-Zebra , Proteína rhoA de Ligação ao GTP/antagonistas & inibidores
3.
J Hepatol ; 64(2): 342-351, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26386161

RESUMO

BACKGROUND & AIMS: The stimulatory G protein α subunit (Gsα) activates the cAMP-dependent pathway by stimulating the production of cAMP and participates in diverse cell processes. Aberrant expression of Gsα results in various pathophysiological disorders, including tumorigenesis, but little is known about its role in liver regeneration. METHODS: We generated a hepatocyte-specific Gsα gene knockout mouse to demonstrate the essential role of Gsα in liver regeneration using a mouse model with 70% partial hepatectomy (PH) or an intraperitoneal injection of carbon tetrachloride (CCl4). RESULTS: Gsα inactivation dramatically impaired liver regeneration and blocked proliferating hepatocytes in G1/S transition due to the simultaneous depression of cyclin-dependent kinase 2 (CDK2) and cyclin E1. Loss of Gsα led to a fundamental alteration in gene profiles. Among the altered signaling cascades, the MAPK/Erk pathway, which is downstream of growth factor signaling, was disrupted secondary to a defect in phosphorylated Raf1 (pRaf1), resulting in a deficiency in phosphorylated CREB (pCREB) and CDK2 ablation. The lack of pRaf1 also resulted in a failure to phosphorylate retinoblastoma, which releases and activates E2F1, and a decrease in cyclin E1. Although these factors could be phosphorylated through both Gsα and growth factor signaling, the unique function of Raf1 in the growth factor cascade collapsed in response to the lack of Gsα. CONCLUSION: The growth factor signaling pathway that promotes hepatocyte proliferation is dependent on Gsα signaling. Loss of Gsα leads to a breakdown of the crosstalk between cAMP and growth factor signaling and dramatically impairs liver regeneration.


Assuntos
AMP Cíclico/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP , Hepatócitos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Regeneração Hepática/fisiologia , Animais , Proliferação de Células/fisiologia , Quinase 2 Dependente de Ciclina/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Genes cdc/fisiologia , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Camundongos Knockout , Transdução de Sinais/fisiologia
4.
Small ; 12(15): 2067-76, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26914158

RESUMO

Extracorporeal devices have great promise for cleansing the body of virulence factors that are caused by venomous injuries, bacterial infections, and biological weaponry. The clinically used extracorporeal devices, such as artificial liver-support systems that are mainly based on dialysis or electrostatic interaction, are limited to remove a target toxin. Here, a liver-mimetic device is shown that consists of decellularized liver scaffold (DLS) populated with polydiacetylene (PDA) nanoparticles. DLS has the gross shape and 3D architecture of a liver, and the PDA nanoparticles selectively capture and neutralize the pore-forming toxins (PFTs). This device can efficiently and target-orientedly remove PFTs in human blood ex vivo without changing blood components or activating complement factors, showing potential application in antidotal therapy. This work provides a proof-of-principle for blood detoxification by a nanoparticle-activated DLS, and can lead to the development of future medical devices for antidotal therapy.


Assuntos
Inativação Metabólica , Fígado/citologia , Nanopartículas/química , Alicerces Teciduais/química , Animais , Biomimética , Humanos , Nanopartículas/ultraestrutura , Polímero Poliacetilênico , Polímeros/química , Poli-Inos/química , Ratos , Soluções , Toxinas Biológicas/isolamento & purificação
6.
Int J Med Sci ; 12(5): 397-406, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26005374

RESUMO

The use of toxins for cancer therapy has great promise. Gelonin, a potent plant toxin, causes cell death by inactivating the 60S ribosomal subunit. Recently, we developed a novel gene delivery system using biodegradable cationic heparin-polyethyleneimine (HPEI) nanogels. In the current study, the antitumor activity of a recombinant plasmid expressing gelonin (pGelonin) on human ovarian cancer was assessed. The application of HPEI nanogels, was also evaluated. Gelonin-cDNA was cloned into the pVAX1 plasmid vector and transfected into SKOV3 human ovarian cancer cells using biodegradable cationic HPEI nanogels. The expression of gelonin in vitro and in vivo was confirmed using RT-PCR and western blot analysis. Cell viability and apoptosis were examined using an MTT assay and flow cytometric analysis. For the in vivo study, an SKOV3 intraperitoneal ovarian carcinomatosis model was established, and nude mice were randomly assigned into four groups receiving i.p. administration of pGelonin/HPEI complexes, pVAX/HPEI complexes, HPEI alone and 5% glucose solution. The tumor weight was monitored, and a TUNEL assay and Ki-67 immunohistochemistry were performed to evaluate apoptosis and cell proliferation in the tumor tissue sections, respectively. Gelonin was efficiently expressed in SKOV3 cancer cells in vitro and in vivo using pGelonin incorporated with HPEI nanogels. The pGelonin/HPEI complexes inhibited cell viability and induced apoptosis in the cell culture. Treatment for intraperitoneal carcinomatosis with pGelonin/HPEI complexes reduced the tumor weight by ~58.55% compared to the control groups (P<0.05). The antitumor effect was accompanied by increased apoptosis and reduced cell proliferation (P<0.05). No significant side effects were observed with i.p. administration of the pGelonin/HPEI complexes. Our data indicate that HPEI nanogel-delivered pGelonin may have promising applications against human ovarian cancer.


Assuntos
Terapia Genética/métodos , Heparina/química , Neoplasias Ovarianas/terapia , Polietilenoglicóis/administração & dosagem , Polietilenoimina/administração & dosagem , Proteínas Inativadoras de Ribossomos Tipo 1/farmacologia , Animais , Apoptose/genética , Materiais Biocompatíveis , Cátions , Linhagem Celular , Feminino , Técnicas de Transferência de Genes , Heparina/administração & dosagem , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanogéis , Neoplasias Ovarianas/patologia , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Polietilenoimina/química , Polietilenoimina/toxicidade , Proteínas Inativadoras de Ribossomos Tipo 1/administração & dosagem , Proteínas Inativadoras de Ribossomos Tipo 1/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Nanosci Nanotechnol ; 15(9): 6397-404, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26716193

RESUMO

Camptothecin (CPT) exerts very strong antitumor activities by suppressing the activity of DNA topoisomerase I, but its application is greatly limited owing to its low solubility and the instability of the active lactone form. To overcome this bottleneck, we prepared the novel camptothecin nanocolloids based on N-trimethyl chitosan (CPT-TMC) to efficiently administer CPT systemically. In this study, we investigated the antitumor activity of CPT-TMC against both colon cancer and lung cancer. In vitro cell experiments both CPT and CPT-TMC significantly inhibited the growth of CT26 cells and LL/2 cells, but no statistical difference was observed between CPT-TMC and CPT. In vivo studies, CPT-TMC more effectively inhibited tumor growth and prolonged survival time than CPT both in the CT26 colon carcinoma subcutaneous model and in the LL/2 Lewis lung carcinoma subcutaneous model. In addition, results of PCNA and CD31 immunohistochemical staining of tumor tissues also confirmed the improved antitumor effect of CPT-TMC. These findings suggest that N-trimethyl chitosan could increase the antitumor effect of CPT. Consequently, CPT delivery by N-trimethyl chitosan is a potential approach for effective treatment of cancer.


Assuntos
Antineoplásicos/farmacologia , Camptotecina/farmacologia , Quitosana/química , Portadores de Fármacos/química , Animais , Antineoplásicos/química , Antineoplásicos/toxicidade , Camptotecina/química , Camptotecina/toxicidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quitosana/toxicidade , Neoplasias do Colo , Portadores de Fármacos/toxicidade , Feminino , Neoplasias Pulmonares , Camundongos , Camundongos Endogâmicos BALB C
8.
J Mater Chem B ; 12(24): 5812-5822, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38856691

RESUMO

Immunotherapy is an important approach in cancer treatment. Transdermal administration is emerging as a promising method for delivering immunotherapeutics. Dissolving microneedles are made mainly of soluble or biodegradable polymers and have garnered widespread attention due to their painlessness, safety, convenience, excellent drug loading capacity, and easy availability of various materials, making them an ideal transdermal delivery system. This review comprehensively summarized the preparation methods, materials, and applications of dissolving microneedles in cancer vaccines, immune checkpoint inhibitors, and adoptive cell therapy. Additionally, the challenges and perspectives associated with their future clinical translation are discussed.


Assuntos
Administração Cutânea , Sistemas de Liberação de Medicamentos , Imunoterapia , Agulhas , Neoplasias , Humanos , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Animais , Vacinas Anticâncer/administração & dosagem
9.
Small Methods ; 8(3): e2301121, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38009766

RESUMO

3D printing is now recognized as a significant tool for medical research and clinical practice, leading to the emergence of medical 3D printing technology. It is essential to improve the properties of 3D-printed products to meet the demand for medical use. The core of generating qualified 3D printing products is to develop advanced materials and processes. Taking advantage of nanomaterials with tunable and distinct physical, chemical, and biological properties, integrating nanotechnology into 3D printing creates new opportunities for advancing medical 3D printing field. Recently, some attempts are made to improve medical 3D printing through nanotechnology, providing new insights into developing advanced medical 3D printing technology. With high-resolution 3D printing technology, nano-structures can be directly fabricated for medical applications. Incorporating nanomaterials into the 3D printing material system can improve the properties of the 3D-printed medical products. At the same time, nanomaterials can be used to expand novel medical 3D printing technologies. This review introduced the strategies and progresses of improving medical 3D printing through nanotechnology and discussed challenges in clinical translation.


Assuntos
Nanoestruturas , Impressão Tridimensional , Nanoestruturas/uso terapêutico , Nanotecnologia
10.
Adv Sci (Weinh) ; 11(17): e2306076, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38445883

RESUMO

Earthworms, long utilized in traditional medicine, serve as a source of inspiration for modern therapeutics. Lysenin, a defensive factor in the coelom fluid of the earthworm Eisenia fetida, has multiple bioactivities. However, the inherent toxicity of Lysenin as a pore-forming protein (PFP) restricts its application in therapy. Here, a gene therapy strategy based on Lysenin for cancer treatment is presented. The formulation consists of polymeric nanoparticles complexed with the plasmid encoding Lysenin. After transfection in vitro, melanoma cells can express Lysenin, resulting in necrosis, autophagy, and immunogenic cell death. The secretory signal peptide alters the intracellular distribution of the expressed product of Lysenin, thereby potentiating its anticancer efficacy. The intratumor injection of Lysenin gene formulation can efficiently kill the transfected melanoma cells and activate the antitumor immune response. Notably, no obvious systemic toxicity is observed during the treatment. Non-viral gene therapy based on Lysenin derived from Eisenia foetida exhibits potential in cancer therapy, which can inspire future cancer therapeutics.


Assuntos
Terapia Genética , Melanoma , Oligoquetos , Animais , Camundongos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Terapia Genética/métodos , Melanoma/terapia , Melanoma/genética , Nanopartículas/química , Oligoquetos/genética , Toxinas Biológicas/genética , Feminino , Humanos
11.
Int J Bioprint ; 9(5): 760, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457931

RESUMO

The application of three-dimensional (3D) bioprinting has increased in the biomedical field. The lack of bioinks with both biocompatibility and printability is still a problem to be solved. Silk fibroin materials have good biocompatibility and have a broad application prospect in the field of biomedical materials. At present, most research usually involves Bombyx mori silk fibroin (BSF). However, BSF has low cell adhesion. Compared with BSF, Antheraea pernyi silk fibroin (ASF) isolated from typical non-mulberry silk exhibits a unique arginine-glycine-aspartate (RGD) sequence with good cell adhesion enhancement. In this study, we developed a bioink based on ASF for digital light processing (DLP) 3D bioprinting. The ASF-based bioinks (ASF-MA) were produced by a methacryloylation process using methacrylic anhydride (MA) to achieve the properties of photopolymerization reaction. The ASF-MA hydrogel has mechanical properties, biocompatibility, and especially cell adhesion. Meanwhile, we found that the ASF-MA hydrogels promoted the adhesion, migration, and proliferation of S16 cells. Hence, the ASF-MA hydrogels had the potential applications in biomedical fields.

12.
Mater Today Bio ; 20: 100652, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37214548

RESUMO

Nerve guide conduit is a promising treatment for long gap peripheral nerve injuries, yet its efficacy is limited. Drug-releasable scaffolds may provide reliable platforms to build a regenerative microenvironment for nerve recovery. In this study, an elastic hydrogel conduit encapsulating with prodrug nanoassemblies is fabricated by a continuous 3D printing technique for promoting nerve regeneration. The bioactive hydrogel is comprised of gelatin methacryloyl (GelMA) and silk fibroin glycidyl methacrylate (SF-MA), exhibiting positive effects on adhesion, proliferation, and migration of Schwann cells. Meanwhile, 7,8-dihydroxyflavone (7,8-DHF) prodrug nanoassemblies with high drug-loading capacities are developed through self-assembly of the lipophilic prodrug and loaded into the GelMA/SF-MA hydrogel. The drug loading conduit could sustainedly release 7,8-DHF to facilitate neurite elongation. A 12 â€‹mm nerve defect model is established for therapeutic efficiency evaluation by implanting the conduit through surgical suturing with rat sciatic nerve. The electrophysiological, morphological, and histological assessments indicate that this conduit can promote axon regeneration, remyelination, and function recovery by providing a favorable microenvironment. These findings implicate that the GelMA/SF-MA conduit with 7,8-DHF release has potentials in the treatment of long-gap peripheral nerve injury.

13.
Mol Biomed ; 4(1): 1, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36602633

RESUMO

Hair loss is a common skin disease that causes intense emotional suffering. Hair regeneration in a personalized area is highly desirable for patients with different balding conditions. However, the existing pharmaceutical treatments have difficulty precisely regenerating hair in a desired area. Here, we show a method to precisely control the hair regeneration using customized microneedle arrays (MNAs). The MNA with a customized shape is fast fabricated by a static optical projection lithography process in seconds, which is a 3D printing technology developed by our group. In the mouse model, MNA treatment could induce hair regrowth in a defined area corresponding to the customized shape of MNA. And the regenerated hair promoted by MNAs had improved quality. Cellular and molecular analysis indicated that MNA treatment could recruit macrophages in situ and then initiate the proliferation of hair follicle stem cells, thereby improving hair regeneration. Meanwhile, the activation of the Wnt/ß-catenin signaling pathway was observed in hair follicles. The expressions of Hgf, Igf 1 and Tnf-α were also upregulated in the treated skin, which may also be beneficial for the MNA-induced hair regeneration. This study provides a strategy to precisely control hair regeneration using customized microneedle arrays by recruiting macrophages in situ, which holds the promise for the personalized treatment of hair loss.

14.
Adv Healthc Mater ; 12(7): e2202169, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36398560

RESUMO

The unique structure of the periodontium, including the alveolar bone, cementum, and periodontal ligament (PDL), presents difficulties for the regeneration of its intricate organization. Irreversible structural breakdown of the periodontium increases the risk of tooth loosening and loss. Although the current therapies can restore the periodontal hard tissues to a certain extent, the PDL with its high directionality of multiple groups with different orientations and functions cannot be reconstructed. Here, biomimetic peridontium patches (BPPs) for functional periodontal regeneration using a microscale continuous digital light projection bioprinting method is reported. Orthotopic transplantation in the mandibles shows effective periodontal reconstruction. The resulting bioengineered tissues closely resembles natural periodontium in terms of the "sandwich structures," especially the correctly oriented fibers, showing different and specific orientation in different regions of the tooth root, which has never been found in previous studies. Furthermore, after the assessment of clinically functional properties it is found that the regenerative periodontium can achieve stable tooth movement under orthodontic migration force with no adverse consequences. Overall, the BPPs promote reconstruction of the functional periodontium and the complex microstructure of the periodontal tissue, providing a proof of principle for the clinical functional treatment of periodontal defects.


Assuntos
Biomimética , Ligamento Periodontal , Periodonto , Raiz Dentária
15.
Int J Pharm ; 626: 122187, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36100145

RESUMO

Detoxification of glutathione (GSH) and insufficient cellular uptake of cisplatin (CDDP) severely compromised the therapeutic efficacy of CDDP. Here, a nano-delivery system (BT-4@PtPPNPs) for CDDP prodrug (C16-Pt(Ⅳ)-PEG) based on a novel sulfhydryl blocking reagent methyl 2-(methylsulfonyl) benzothiazole-6-carboxylate (BT-4) was developed. On the one hand, BT-4 can deplete GSH in tumor cells by directly interacting with reactive sulfhydryl group on GSH, thereby increasing the cytotoxicity of CDDP. On the other hand, the CDDP prodrug carrier C16-Pt(IV)-PEG can promote the distribution of CDDP in tumors, reduce the probability of unexpected inactivation of CDDP, and reduce the content of GSH in tumor cells during the conversion to CDDP, thereby making CDDP more effective for treatment. The results showed that the optimized BT-4@PtPPNPs with a small particle size (130 nm) exhibited notable cytotoxicity and apoptosis of 4T1 cells. BT-4@PtPPNPs not only significantly improved the uptake of drugs by tumor cells, but also rapidly targeted and accumulated in the tumors for a long time. Moreover, in vivo efficacy studies showed that BT-4@PtPPNPs could effectively inhibit tumor growth, inhibiting 60.85 % of tumors in a 4T1 breast cancer mice model, showing superior antitumor activity, which can be attributed to GSH-triggered CDDP tolerance reversal. Overall, this study provides an attractive and simple strategy to combine novel sulfhydryl blockers and CDDP prodrugs to potentiate the efficacy of CDDP in breast cancer.


Assuntos
Antineoplásicos , Neoplasias , Pró-Fármacos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Benzotiazóis , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Glutationa , Camundongos , Micelas , Neoplasias/tratamento farmacológico , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico
16.
Int J Bioprint ; 8(2): 553, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669318

RESUMO

Hollow microneedle patches (HMNPs) have great promise for efficient and precise transdermal drug delivery in a painless manner. Currently, the clinical application of HMNPs is restricted by its complex manufacturing processes. Here, we use a new three-dimensional (3D) printing technology, static optical projection lithography (SOPL), for the fast fabrication of HMNPs. In this technology, a light beam is modulated into a customized pattern by a digital micromirror device (DMD) and projected to induce the spatial polymerization of monomer solutions which is controlled by the distribution of the light intensity in the monomer solutions. After an annulus picture is inputted into the DMD via the computer, the microneedles with hollow-cone structure can be precisely printed in seconds. By designing the printing pictures, the personalized HMNPs can be fast customized, which can afford the scale-up preparation of personalized HMNPs. Meanwhile, the obtained hollow microneedles (HMNs) have smooth surface without layer-by-layer structure in the commonly 3D-printed products. After being equipped with a micro-syringe, the HMNPs can efficiently deliver insulin into the skin by injection, resulting in effective control of the blood glucose level in diabetic mice. This work demonstrates a SOPL-based 3D printing technology for fast customization of HMNPs with promising medical applications.

17.
Burns Trauma ; 10: tkac010, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35441080

RESUMO

Background: Nerve transfer is an important clinical surgical procedure for nerve repair by the coaptation of a healthy donor nerve to an injured nerve. Usually, nerve transfer is performed in an end-to-end manner, which will lead to functional loss of the donor nerve. In this study, we aimed to evaluate the efficacy of 3D-printed branch nerve conduits in nerve transfer. Methods: Customized branch conduits were constructed using gelatine-methacryloyl by 3D printing. The nerve conduits were characterized both in vitro and in vivo. The efficacy of 3D-printed branch nerve conduits in nerve transfer was evaluated in rats through electrophysiology testing and histological evaluation. Results: The results obtained showed that a single nerve stump could form a complex nerve network in the 3D-printed multibranch conduit. A two-branch conduit was 3D printed for transferring the tibial nerve to the peroneal nerve in rats. In this process, the two branches were connected to the distal tibial nerve and peroneal nerve. It was found that the two nerves were successfully repaired with functional recovery. Conclusions: It is implied that the two-branch conduit could not only repair the peroneal nerve but also preserve partial function of the donor tibial nerve. This work demonstrated that 3D-printed branch nerve conduits provide a potential method for nerve transfer.

18.
J Control Release ; 350: 933-948, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35977583

RESUMO

Microneedle arrays provide an efficient tool for transdermal drug delivery in a minimally invasive and painless manner, showing great potential applications in medicine. However, it remains challenging to fabricate the desired microneedle arrays, because of their micron-scale size and fine structure. Novel manufacturing technologies are very wanted for the development of microneedle arrays, which would solidly advance the clinical translation of microneedle arrays. 3D printing technology is a powerful manufacturing technology with superiority in fabricating personalized and complex structures. Currently, 3D printing technology has been employed to fabricate microneedle arrays, which could push more microneedle arrays into clinic and inspire the development of future microneedle arrays. This work reviews the art of 3D printing microneedle arrays, the benefits of fabricating microneedle arrays with 3D printing, and the considerations for clinical translation of 3D-printed microneedle arrays. This work provides an overview of the current 3D-printed microneedle arrays in drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Impressão Tridimensional , Administração Cutânea , Preparações Farmacêuticas/química
19.
Burns Trauma ; 10: tkac028, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992369

RESUMO

Adipose-derived stem cells (ADSCs) have promising applications in tissue regeneration. Currently, there are only a few ADSC products that have been approved for clinical use. The clinical application of ADSCs still faces many challenges. Here, we review emerging strategies to improve the therapeutic efficacy of ADSCs in tissue regeneration. First, a great quantity of cells is often needed for the stem cell therapies, which requires the advanced cell expansion technologies. In addition cell-derived products are also required for the development of 'cell-free' therapies to overcome the drawbacks of cell-based therapies. Second, it is necessary to strengthen the regenerative functions of ADSCs, including viability, differentiation and paracrine ability, for the tissue repair and regeneration required for different physiological and pathophysiological conditions. Third, poor delivery efficiency also restricts the therapeutic effect of ADSCs. Effective methods to improve cell delivery include alleviating harsh microenvironments, enhancing targeting ability and prolonging cell retention. Moreover, we also point out some critical issues about the sources, effectiveness and safety of ADSCs. With these advanced strategies to improve the therapeutic efficacy of ADSCs, ADSC-based treatment holds great promise for clinical applications in tissue regeneration.

20.
Artigo em Inglês | MEDLINE | ID: mdl-35544723

RESUMO

Transplantation of encapsulated islets has been shown to hold a promising potential treatment for type 1 diabetes (T1D). However, there are several obstacles to overcome, such as immune rejection by the host of the grafts, sustainability of islet function, and retrievability or replacement of the encapsulated system, hinder their clinical applications. In this study, mini-capsule devices containing islets were fabricated by using digital light processing (DLP) 3D printing. To ensure a high survival rate and low immunogenicity of the fabricated islets, 20s was selected as the most suitable printing condition. Meanwhile, the mini-capsule devices with a groove structure were fabricated to prevent islet cells leakage. Subcutaneous transplantations of encapsulated islets in immunocompetent C57BL/6 mice indicated significant improvement in the symptoms of streptozotocin-induced hyperglycemia without any immunosuppression treatment for at least 15 weeks. In vivo intraperitoneal glucose tolerance tests (IPGTT) performed at different time points demonstrated therapeutically relevant glycemic ameliorate of the device. The implants retrieved after 15 weeks still contained viable and adequate numbers of islet cells. The results of this study indicate that the proposed mini-capsule device can deliver sufficient islet cell mass, prevent islet cells leakage, and maintain long-term cell survival while allowing easy retrieval. Furthermore, the proposed encapsulated islets may help with T1D cellular treatment by overcoming the obstacles of islet transplantation.

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