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1.
Molecules ; 28(16)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37630351

RESUMO

Nanotechnology is revolutionizing the efficient production and sustainable development of modern agriculture. Understanding the pesticide activity of both nano- and conventional methods is useful for developing new pesticide formulations. In this study, three solid fluopyram formulations with varying particle sizes were developed, and the mechanisms underlying the difference in the antifungal activity among these formulations were investigated. Wet media milling combined with freeze drying was used to prepare fluopyram nanoparticles (FLU-NS) and a micron-sized solid formulation (FLU-MS), and a jet grinding mill was employed to fabricate fluopyram wettable powder (FLU-WP). The mean particle sizes of FLU-NS, FLU-MS, and FLU-WP were 366.8 nm, 2.99 µm, and 10.16 µm, respectively. Notably, FLU-NS displayed a toxicity index against Botrytis cinerea (gray mold) that was approximately double those of FLU-MS and FLU-WP. Similar trends were noticed in the antifungal tests on Alternaria solani. The uptake of FLU-NS by B. cinerea was approximately twice that of FLU-MS and FLU-WP, indicating that fluopyram nanoparticles are more easily taken up by the pathogen (B. cinerea), and display better bioactivity than the larger fluopyram particles. Therefore, the nanosizing of pesticides appears to be a viable strategy to enhance efficiency without increasing the amount of pesticide used.


Assuntos
Antifúngicos , Praguicidas , Antifúngicos/farmacologia , Benzamidas
2.
Exp Dermatol ; 31(3): 362-374, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34694648

RESUMO

OBJECTIVE: To investigate the function of miR-126-3p loaded on adipose stem cell (ADSC)-derived exosomes (ADSC-Exos) in wound healing of full-thickness skin defects. METHODS: ADSCs transfected with miR-126-3p mimic, miR-126-3p inhibitor or pcDNA3.1-PIK3R2, or PKH26-marked ADSC-Exos were cultured with fibroblasts or human umbilical vein endothelial cells (HUVECs). The proliferation and migration rates of fibroblasts and angiogenesis of HUVECs were measured. Rats with full-thickness skin defects were injected with ADSC-Exos or exosomes extracted from ADSCs transfected with miR-126-3p inhibitor and the wound healing rates were measured. The wound bed, collagen deposition and angiogenesis in injured rats were assessed. RESULTS: ADSC-Exos could be ingested by fibroblasts and HUVECs. Co-incubation with ADSCs or ADSC-Exos promoted the proliferation and migration of fibroblasts and angiogenesis of HUVECs, which was further enhanced by miR-126-3p overexpression. Inhibition of ADSC-Exos or miR-126-3p or PIK3R2 overexpression suppressed the proliferation and migration of fibroblasts and angiogenesis of HUVECs. ADSC-derived exosomal miR-126-3p increased wound healing rate, collagen deposition and newly formed vessels in the injured rats. CONCLUSION: ADSC-derived exosomal miR-126-3p promotes wound healing of full-thickness skin defects by targeting PIK3R2.


Assuntos
Exossomos , MicroRNAs , Animais , Proliferação de Células , Colágeno , Células Endoteliais da Veia Umbilical Humana , Humanos , MicroRNAs/genética , Ratos , Células-Tronco , Cicatrização/fisiologia
3.
Transpl Int ; 33(4): 450-461, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31930539

RESUMO

Systemic immunosuppression is indispensable for vascularized composite allotransplantation (VCA). Daily administration of standard triple therapy regimen of tacrolimus (FK506), mycophenolate mofetil (MMF), and steroid has severe side effects and reduces the compliance of VCA recipients. To overcome these hurdles, FK506/MMF/prednisolone (PDNN) was loaded into PLGA microspheres (PGLA MS). A single injection of FK506/MMF/PDNN-PLGA MS significantly prolonged the survival time of allograft in a rat hind limb transplantation model with a median survival time (MST) of more than 150 days compared to 34.5 days in the group treated orally with FK506/MMF/PDNN and 11 days in the nontreatment allograft and MS control groups. Analysis of showed that FK506/MMF/PDNN-PLGA MS could maintain relatively higher plasma and tissue drug concentrations for a long time. Moreover, histopathology and flow cytometry of circulating mononuclear cells revealed significantly prolonged immunosuppression by the FK506/MMF/PDNN-PLGA MS compared with the orally given FK506/MMF/PDNN. In conclusion, a single injection of FK506/MMF/PDNN-PLGA MS may provide a new approach for long-term prevention of immune rejection in VCA.


Assuntos
Aloenxertos Compostos , Animais , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Imunossupressores , Microesferas , Ácido Micofenólico , Ratos , Tacrolimo
4.
Dermatol Ther ; 33(4): e13494, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32363669

RESUMO

Keloids are firm, fibrous nodules that form on an individual's skin and are associated with difficult symptoms as well as high recurrence rates. This study aims to improve the surgical techniques that reduce local tension after surgical excision of keloids as well as applying adjuvant radiotherapy to suppress scar formation. A total of 58 patients aged between 21 and 76 years received surgical incision of keloid and immediate postoperation low-dose radiotherapy. All patient follow-ups were performed at the out-patient department. Any sign of a keloid at the incision site was defined as treatment failure or keloid recurrence, regardless of the size. At a median follow-up of 22 months, the overall recurrence for all lesions was 8.6%, which is improved compared with previous study. In addition, all incisions performed during surgeries were healed and no signs of necrosis or the development of ulcers was observed. Our study suggests that this combined therapy provides excellent local control of keloids and shows promise for future therapy.


Assuntos
Queloide , Adulto , Idoso , Terapia Combinada , Elétrons , Humanos , Queloide/patologia , Queloide/radioterapia , Queloide/cirurgia , Pessoa de Meia-Idade , Radioterapia Adjuvante , Recidiva , Resultado do Tratamento , Adulto Jovem
5.
Int Wound J ; 16(3): 793-799, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30767371

RESUMO

Some types of skin and soft tissue tumours may be misdiagnosed as scars because of the scar-like manifestation or the history of injury. It is generally believed that injuries will activate wound healing, ultimately ending in fibrosis. Because of the tumour-promoting properties of both the microenvironment of the wound and the wound-healing process that may go awry, there is a likelihood that injuries may trigger tumour growth. From 2012 to 2016, we treated four patients who underwent unsuccessful treatments because of the misdiagnosis of scars or keloids. Upon the pathological diagnoses of skin and soft tissue tumours in the four cases, extended resection of the tumours was performed. Recurrence was not observed up to the last follow up. Since then, soft tissue tumours have much greater visibility and are considered during diagnosis if a wound is presented with the atypical appearance of scar after injuries. Under these circumstances, biopsy should be conducted.


Assuntos
Cicatriz/fisiopatologia , Cicatriz/cirurgia , Erros de Diagnóstico , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/fisiopatologia , Neoplasias Cutâneas/cirurgia , Cicatrização/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
6.
Proc Natl Acad Sci U S A ; 108(21): 8550-3, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21555550

RESUMO

Aerogel materials have myriad scientific and technological applications due to their large intrinsic surface areas and ultralow densities. However, creating a nanodiamond aerogel matrix has remained an outstanding and intriguing challenge. Here we report the high-pressure, high-temperature synthesis of a diamond aerogel from an amorphous carbon aerogel precursor using a laser-heated diamond anvil cell. Neon is used as a chemically inert, near-hydrostatic pressure medium that prevents collapse of the aerogel under pressure by conformally filling the aerogel's void volume. Electron and X-ray spectromicroscopy confirm the aerogel morphology and composition of the nanodiamond matrix. Time-resolved photoluminescence measurements of recovered material reveal the formation of both nitrogen- and silicon- vacancy point-defects, suggesting a broad range of applications for this nanocrystalline diamond aerogel.

7.
Nano Lett ; 13(4): 1440-5, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23517010

RESUMO

We experimentally demonstrate that plasmonic nanoparticles embedded in the evanescent field of subwavelength optical waveguides (WGs) are highly sensitive to distances normal to the propagation of light, showing an ~10× increase in spatial resolution compared to the optical field decay of the WG. The scattering cross-section of the Au nanoparticle is increased by the plasmon-dielectric coupling interaction when the nanoparticle is placed near the dielectric surface of the WG, and the decay of the scattering signal is enhanced, showing angstrom level distance sensitivity within 10 nm from the WG. Numerical studies with the finite-difference time-domain (FDTD) method correlate well with the experimental results. To demonstrate real-time monitoring of a single molecule stretching in the evanescent field, we linked individual single-stranded DNA molecules between the WG and plasmonic nanoparticles and pushed on the nanoparticles with fluidic forces. The simple design and ease of obtaining optical feedback on molecular displacements makes our approach ideal for new in situ force sensing devices, imaging technologies, and high-throughput molecular analysis.


Assuntos
DNA de Cadeia Simples/química , Nanofibras/química , Nanopartículas/química , DNA de Cadeia Simples/isolamento & purificação , Tecnologia de Fibra Óptica , Ouro/química , Luz , Espalhamento de Radiação
8.
J Invest Dermatol ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38797322

RESUMO

Keloids are a skin fibrosis disease characterized by troublesome symptoms, a varying degree of recurrence and inevitable side effects from treatments. Thus, identifying their drug targets is necessary. A 2-sample Mendelian randomization analysis was conducted using proteins from the intersection of the deCODE database and "The Druggable Genome and Support for Target Identification and Validation in Drug Development" as the exposure variable. The outcome variable was based on recently published GWAS of keloids. Summary data-based Mendelian randomization and colocalization analysis was employed to distinguish pleiotropy from linkage. Candidate targets underwent drug target analysis. The primary findings were validated through single-cell RNA-sequencing data, Western Blot and immunofluorescence staining on keloids. Seven proteins were identified as potential drug targets for keloids. Among these proteins, Hedgehog-interacting protein, neurotrimin [NTM], KLKB1, and CRIPTO showed positive correlations with keloids, while PLXNC1, SCG3 and PDGFD exhibited negative correlations. Combined with the single-cell RNA-sequencing data, NTM, PLXNC1, and PDGFD were found highly expressed in the fibroblasts. NTM showed a significant increase in keloids as compared to normal scars. In accordance with the analysis, higher levels of protein expression of NTM in keloids compared to normal skin was observed. The identified proteins may be appealing drug targets for keloids treatment with a special emphasis on NTM.

9.
ACS Nano ; 18(21): 13781-13793, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38752333

RESUMO

Pine wood nematode (PWN) disease is a globally devastating forest disease caused by infestation with PWN, Bursaphelenchus xylophilus, which mainly occurs through the vector insect Japanese pine sawyer (JPS), Monochamus alternatus. PWN disease is notoriously difficult to manage effectively and is known as the "cancer of pine trees." In this study, dual enzyme-responsive nanopesticides (AVM@EC@Pectin) were prepared using nanocoating avermectin (AVM) after modification with natural polymers. The proposed treatment can respond to the cell wall-degrading enzymes secreted by PWNs and vector insects during pine tree infestation to intelligently release pesticides to cut off the transmission and infestation pathways and realize the integrated control of PWN disease. The LC50 value of AVM@EC@Pectin was 11.19 mg/L for PWN and 26.31 mg/L for JPS. The insecticidal activity of AVM@EC@Pectin was higher than that of the commercial emulsifiable concentrate (AVM-EC), and the photostability, adhesion, and target penetration were improved. The half-life (t1/2) of AVM@EC@Pectin was 133.7 min, which is approximately twice that of AVM-EC (68.2 min). Sprayed and injected applications showed that nanopesticides had superior bidirectional transportation, with five-times higher AVM contents detected in the roots relative to those of AVM-EC when sprayed at the top. The safety experiment showed that the proposed treatment had lower toxicity and higher safety for nontarget organisms in the application environment and human cells. This study presents a green, safe, and effective strategy for the integrated management of PWN disease.


Assuntos
Biomassa , Ivermectina , Pinus , Animais , Pinus/parasitologia , Pinus/química , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Ivermectina/química , Ivermectina/metabolismo , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , Nematoides/efeitos dos fármacos , Inseticidas/farmacologia , Inseticidas/química , Nanopartículas/química , Humanos
10.
Artigo em Inglês | MEDLINE | ID: mdl-38874450

RESUMO

Chronic hyperglycemia can result in damage to the hippocampus and dysfunction of the blood-brain barrier (BBB), potentially leading to neurological disorders. This study examined the histological structure of the hippocampus and the expression of critical genes associated with the BBB at 2 early stage time points in a streptozotocin-induced diabetes mellitus (DM) mouse model. Routine histology revealed vascular congestion and dilation of Virchow-Robin spaces in the hippocampal CA1 region of the DM group. Neuronal alterations included rounding and swelling and reduction in Nissl bodies and increased apoptosis. Compared to the control group, TJP1 mRNA expression in the DM group was significantly lower (P < .05 or P < .01), while mRNA levels of JAM3, TJP3, CLDN5, CLDN3, and OCLN initially increased and then decreased. At 7, 14, and 21 days, mRNA levels of the receptor for advanced glycation end products (AGER) were greater in the DM group than in the control group (P < .05 or P < .01). These findings indicate that early-stage diabetes may cause structural and functional impairments in hippocampal CA1 in mice. These abnormalities may parallel alterations in the expression of key BBB tight junction molecules and elevated AGER expression in early DM patients.

11.
Phys Rev Lett ; 110(13): 135501, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23581334

RESUMO

The irreversible damage at cracks during the fatigue of crystalline solids is well known. Here we report on in situ high-energy x-ray evidence of reversible fatigue behavior in a nanocrystalline NiFe alloy both in the plastic zone and around the crack tip. In the plastic zone, the deformation is fully recoverable as the crack propagates, and the plastic deformation invokes reversible interactions of dislocation and twinning in the nanograins. But around the crack tip lies a regime with reversible grain lattice reorientation promoted by a change of local stress state. These observations suggest unprecedented fatigue deformation mechanisms in nanostructured systems that are not addressed theoretically.

12.
Facial Plast Surg Aesthet Med ; 25(3): 238-243, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35856821

RESUMO

Background: Bifid nose is a representative indicator of a facial cleft in patients with frontonasal dysplasia. There is no consensus on effective methods to correct bifid nose deformities due to their varied expressions and limited reports of surgical treatments. In this article, we propose using a split M-shaped flap to treat severe dorsal and alar deformities in patients with a bifid nose. Methods: From 2012 to 2021, a total of 26 bifid nose patients underwent surgical correction of their nasal deformities, which were characterized by cleft and board dorsum, alar defects, shortened nose, and shortened or absent nasal tip. These surgeries were performed with the transposition of an M-shaped split flap. Nasal length and nasolabial angle were assessed before and after surgery. Indications, outcomes, and complications were analyzed. Patient satisfaction was evaluated using a self-assessment survey. Results: Postoperative evaluation showed stable results with increased nasal length and improved nasal appearance. Complications were seen in difficulty breathing through the nose and persistent nostril deformities. The majority of patients (92.3%) were satisfied with their surgical outcome. Conclusion: Split M-shaped flap for bifid nose treatment provides improved nasal appearance with a high patient acceptance and stable postoperative results. Clinical Trial registration: chictr.org identifier ChiCTR2000039275.


Assuntos
Fenda Labial , Rinoplastia , Humanos , Fenda Labial/cirurgia , Nariz/cirurgia , Nariz/anormalidades , Rinoplastia/métodos , Resultado do Tratamento
13.
Int J Biol Macromol ; 241: 124561, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37094645

RESUMO

Developing an efficient drug delivery system to mitigate the harm caused by root-knot nematodes is crucial. In this study, enzyme-responsive release abamectin nanocapsules (AVB1a NCs) were prepared using 4, 4-diphenylmethane diisocyanate (MDI) and sodium carboxymethyl cellulose as response release factors. The results showed that the average size (D50) of the AVB1a NCs was 352 nm, and the encapsulation efficiency was 92 %. The median lethal concentration (LC50) of AVB1a NCs for Meloidogyne incognita activity was 0.82 mg L-1. Moreover, AVB1a NCs improved the permeability of AVB1a to root-knot nematodes and plant roots and the horizontal and vertical soil mobility. Furthermore, AVB1a NCs greatly reduced the adsorption of AVB1a by the soil compared to AVB1a emulsifiable concentrate (EC), and the effect of the AVB1a NCs on controlling root-knot nematode disease was increased by 36 %. Compared to the AVB1a EC, the pesticide delivery system significantly reduced the acute toxicity to the soil biological earthworms by approximately 16 times that of the AVB1a and had a lower overall impact on the soil microbial communities. This enzyme-responsive pesticide delivery system had a simple preparation method, excellent performance, and high level of safety, and thus has great application potential for plant diseases and insect pests control.


Assuntos
Nanocápsulas , Praguicidas , Solanum lycopersicum , Tylenchoidea , Animais , Carboximetilcelulose Sódica/farmacologia , Praguicidas/farmacologia , Solo , Sódio/farmacologia
14.
Pest Manag Sci ; 79(10): 3808-3818, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37209281

RESUMO

BACKGROUND: Some traditional pesticide formulations are inefficient, leading to excessive use and abuse of pesticides, which in turn effects environment. Intelligent release pesticide formulations are ideal for improving pesticide utilization and persistence while reducing environmental pollution. RESULTS: We designed a benzil-modified chitosan oligosaccharide (CO-BZ) to encapsulate avermectin (Ave). Ave@CO-BZ nanocapsules are prepared based on a simple interfacial method via cross-linking of CO-BZ with diphenylmethane diisocyanate (MDI). The Ave@CO-BZ nanocapsules have an average particle size of 100 nm and exhibited a responsive release performance for ROS. The cumulative release rate of nanocapsules at 24 h with ROS increased by about 11.4% compared to that without ROS. The Ave@CO-BZ nanocapsules displayed good photostability. Ave@CO-BZ nanocapsules can penetrate root-knot nematodes more easily and exhibited better nematicidal activity against root-knot nematodes. The pot experiment showed that the control effect of Ave CS at low concentration was 53.31% at the initial stage of application (15 d), while Ave@CO-BZ nanocapsules was 63.54%. Under the same conditions, the control effect of Ave@CO-BZ nanocapsules on root-knot nematodes was 60.00% after 45 days of application, while Ave EC was only 13.33%. The acute toxicity experiments of earthworms showed that the toxicity of nanocapsules was significantly lower than that of EC. CONCLUSION: The ROS-responsive nanocapsules can improve the utilization of pesticides and non-target biosafety. This modified chitosan oligosaccharide has great potential as a bio stimuli-responsive material, and this simple and convenient method for preparing Ave@CO-BZ nanocapsules provides a direction for the effective utilization of pesticides. © 2023 Society of Chemical Industry.


Assuntos
Quitosana , Nanocápsulas , Praguicidas , Praguicidas/toxicidade , Espécies Reativas de Oxigênio , Oligossacarídeos
15.
Proc Natl Acad Sci U S A ; 106(33): 13780-4, 2009 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-19667177

RESUMO

Modern means of communication rely on electric fields and currents to carry the flow of information. In contrast, biological systems follow a different paradigm that uses ion gradients and currents, flows of small molecules, and membrane electric potentials. Living organisms use a sophisticated arsenal of membrane receptors, channels, and pumps to control signal transduction to a degree that is unmatched by manmade devices. Electronic circuits that use such biological components could achieve drastically increased functionality; however, this approach requires nearly seamless integration of biological and manmade structures. We present a versatile hybrid platform for such integration that uses shielded nanowires (NWs) that are coated with a continuous lipid bilayer. We show that when shielded silicon NW transistors incorporate transmembrane peptide pores gramicidin A and alamethicin in the lipid bilayer they can achieve ionic to electronic signal transduction by using voltage-gated or chemically gated ion transport through the membrane pores.


Assuntos
Fontes de Energia Bioelétrica , Nanopartículas Metálicas/química , Silício/química , Alameticina/química , Antibacterianos/química , Eletroquímica/métodos , Gramicidina/química , Concentração de Íons de Hidrogênio , Canais Iônicos/química , Ligantes , Bicamadas Lipídicas/química , Modelos Químicos , Nanotecnologia/métodos , Nanofios , Transdução de Sinais
16.
Facial Plast Surg Aesthet Med ; 24(5): 352-356, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687387

RESUMO

Background: The cervical or thoracic region is currently the main donor site for repair of facial multiunit defects (FMUDs); however, its extensive clinical utilization encompasses the need for flap prefabrication and microsurgical techniques. Objective: To illuminate the feasibility of treating FMUD with expanded scalp flaps and laser depilation. Methods: From 2016 to 2020, 17 patients with facial giant congenital melanocytic nevi (GCMN) underwent scalp expansion for FMUD reconstruction. A three-stage surgical treatment plan was attempted and laser depilation was scheduled during the expansion period and postrepair surgeries. Results: All the flaps survived successfully and were able to cover the entire facial defect. The average three-stage treatment time was 4.5 ± 1.3 months. The defect sites included the forehead, nose, cheek, temporal, and eye areas. The maximum defect area was 9 × 30 cm. The average number of laser treatments was 4.6 ± 2.9 times. The average treatment period was 26.8 months. Sixteen patients (94.1%) reported satisfactory outcome. Conclusion: Expanded scalp flap combined with laser depilation is feasible for FMUD repair and warrants further investigation. Clinical Trail Registration Information: Translational Medicine Ethics Review Committee, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine (SH9H-2021-T144-3).


Assuntos
Remoção de Cabelo , Procedimentos de Cirurgia Plástica , Criança , China , Remoção de Cabelo/métodos , Humanos , Lasers , Procedimentos de Cirurgia Plástica/métodos , Couro Cabeludo/cirurgia , Transplante de Pele
17.
Front Bioeng Biotechnol ; 10: 938798, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992352

RESUMO

Common commercial porcine acellular dermal matrix (PADM) products take the form of a thin membrane. Given its dense structure, delaying vascularization after implantation remains an issue to be solved. In addition, overlaying multiple sheets to address deep wounds and large tissue defects that are difficult to repair by self-tissues could hinder tissue ingrowth, angiogenesis, and integration. Here, we creatively prepared PADM microparticles through a homogenizing treatment and crosslinked them to ADM sponges by thermal crosslinking (VT-ADM) and thermal-glutaraldehyde crosslinking (GA-ADM). The resulting VT-ADM was thicker than GA-ADM, and both maintained the natural dermal matrix microstructure and thermal stability. The porosity of GA-ADM (mean 82%) was lower than that of VT-ADM (mean 90.2%), but the mechanical strength and hydrophilicity were significantly higher. The two types of ADM sponges showed no obvious difference in cell adhesion and proliferation without cytotoxicity. Furthermore, the human adipose stem cells were co-cultured with ADM sponges which promoted proliferation, tube formation, and migration of endothelial cells, and the GA-ADM group exhibited better migration behavior. There were no markable differences among expressions of pro-angiogenesis genes, including vascular endothelial growth factor, insulin-like growth factor-1, and epidermal growth factor. In a nude mouse model, the VT-ADM and GA-ADM pre-cultured with human adipose stem cells for 1 week in advance were implanted subcutaneously. The VT-ADM and the GA-ADM showed great histocompatibility without local redness, swelling, or necrosis. The vascular density of the local skin flap above the material was visualized using indocyanine green and showed no statistical difference between the two groups. The collagen tissue deposition in the pores and vessel formation within the sponges increased with time. Although VT-ADM had a higher degradation rate in vivo, the integrity of the two scaffolds was preserved. Collectively, the VT-ADM and the GA-ADM retained a natural matrix structure and presented biocompatibility. Thus, the above-mentioned two crosslinking methods for ADM sponges are safe and practicable. The novel ADM sponges with good physicochemical and biological properties are no longer limited to membrane tissue regeneration but could also realize structure remodeling where they act as scaffolds for a soft tissue filler and three-dimensional reconstruction of the tissue with strength requirements.

18.
Nano Lett ; 10(12): 4901-7, 2010 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-21062047

RESUMO

We demonstrate an organic/inorganic hybrid energy-harvesting platform, based on nanostructured piezolelectric arrays embedded in an environmental-responsive polymer matrix, which can self-generate electrical power by scavenging energy from the environment. A proof of principle device is designed, fabricated, and tested using vertically aligned ZnO nanowires and heat as the local energy source. The device layout takes advantage of the collective stretching motion of piezoelectric ZnO NWs, induced by the shape-change of the matrix polymer, to convert the thermal energy into direct current with output power densities of ∼20 nW/cm(2) at a heating temperature of ∼65 °C. The responsive nature of polymeric matrices to various stimuli makes this nanostructured piezoelectric architecture a highly versatile approach to scavenging energy from a multitude of environments including fluid-based and chemical-rich systems.

19.
Stem Cell Res Ther ; 12(1): 94, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514430

RESUMO

BACKGROUND: The long-term survival after vascularized composite allotransplantation (VCA) is often limited by systemic rejection as well as the adverse effects of immunosuppressants. The stromal vascular fraction (SVF) can be expanded to produce adipose-derived stem cells (ADSC) which represents a combination of endothelial cells, preadipocytes, immune cells, and ADSC. It has been demonstrated that ADSC possess consistently reliable clinical results. However, literature is scarce regarding SVF in VCA. This study seeks to determine the impact of ex vivo allograft pretreatment in combination with SVF cells in the ability to promote composite tissue allotransplantation immunotolerance. METHODS: A rat hind limb allotransplant model was used to investigate the influence of ex vivo pretreatment of SVF and ADSC on VCA survival. Intravascular cell-free saline, ADSC, or SVF was infused into the models with immunosuppressants. The histopathological examination and duration that the allografts went without displaying symptoms of rejection was documented. Peripheral T lymphocytes and Tregs were quantified with flow cytometry while allotissue expressions of CD31 were quantified with immunohistochemical staining (IHC). ELISA was used to detect vascular endothelial growth factor (VEGF)-A as well as anti- and pro-inflammatory cytokines. RESULTS: We demonstrated that ex vivo treatment of allografts with SVF or ADSC prolonged allograft survival in contrast to medium control cohorts. There were also enhanced levels of immunomodulatory cytokines and increased VEGF-A and CD31 expression as well as reduced infiltration and proliferation of T lymphocytes along with raised Treg expressions. CONCLUSION: These studies demonstrated that adipose-derived cellular therapies prolong graft survival in an allogenic hind limb transplantation model and have the potential to establish immunotolerance.


Assuntos
Sobrevivência de Enxerto , Fator A de Crescimento do Endotélio Vascular , Tecido Adiposo , Animais , Células Endoteliais , Ratos , Ratos Endogâmicos Lew , Fator A de Crescimento do Endotélio Vascular/genética
20.
Stem Cell Res Ther ; 12(1): 440, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362454

RESUMO

BACKGROUND: Autologous adipose tissue transfer may be performed for aesthetic needs following the resection of dermatofibrosarcoma protuberans (DFSP), the most common cutaneous soft tissue sarcoma, excluding Kaposi sarcoma. The regenerative effectiveness of cell-assisted lipotransfer is dependent on the presence of adipose tissue-derived stem cells (ADSCs). This is the first study to evaluate the potential oncological risks as ADSCs could unintentionally be sited within the proximity of the tumor microenvironment of DFSP cells. METHODS: Primary DFSP cells were indirectly co-cultured with ADSCs in a conditioned medium or in a Transwell system. The impact was analyzed by assessing proliferation, migration, invasion, angiogenesis, and tumor-associated genes and proteins. Results of these assays were compared between co-culture and mono-culture conditions. RESULTS: Our experimental results showed that ADSCs were able to promote proliferation, migration, invasion, and angiogenesis of DFSP cells; this was accompanied by a significant increase in the expression levels of beta-type platelet-derived growth factor receptor, collagen type I alpha 1 chain, vascular endothelial growth factor, hepatocyte growth factor, and basic fibroblast growth factor. CONCLUSIONS: The current report clearly demonstrates that ADSCs can enhance different malignant properties of DFSP cells in vitro, which should not be neglected when considering the clinical use of human ADSCs and its related derivatives in skin regenerative therapies.


Assuntos
Dermatofibrossarcoma , Neoplasias Cutâneas , Tecido Adiposo , Proliferação de Células , Técnicas de Cocultura , Cadeia alfa 1 do Colágeno Tipo I , Dermatofibrossarcoma/genética , Dermatofibrossarcoma/terapia , Humanos , Neoplasias Cutâneas/terapia , Células-Tronco , Microambiente Tumoral , Fator A de Crescimento do Endotélio Vascular
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