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2.
Int J Biol Macromol ; 253(Pt 4): 126960, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37741482

RESUMO

Periodontal defect seriously affects people's life health and quality. Guided tissue regeneration (GTR) and guided bone regeneration (GBR) have made great progress in periodontal disease treatment, but some deficiencies existed in commercial materials of GTR and GBR. For obtaining better therapeutic effects, multifunctional composite scaffolds containing different biological macromolecules were developed in this study. Chitosan/poly (γ-glutamic acid)/nano-hydroxyapatite hydrogels (CP/nHA) made by electrostatic interactions and lyophilization were filled in the bone defects to achieve osteogenesis. Platelet-rich fibrin (PRF) extracted from blood could accelerate bone formation by releasing various bioactive substances as middle layer of composite scaffolds. Polycaprolactone/gelatin nanofibers (PG) prepared by electrospinning were attached to the junction of soft and hard tissue, which could prevent fibrous tissue from infiltrating into bone defects. The composite scaffolds showed good morphology, biocompatibility, cell barriers and osteogenic differentiation in vitro. The excellent ability of bone formation was verified by implantation of triple-layered composite scaffolds into alveolar bone defects in rabbit in vivo. The hierarchical structure was conducive to personalized customization to meet the needs of different defects. All in all, the multifunctional scaffolds could play important roles of GTR and GBR in alveolar bone regeneration and provide good application prospect for bone repair in clinic.


Assuntos
Regeneração Tecidual Guiada , Nanofibras , Fibrina Rica em Plaquetas , Animais , Humanos , Coelhos , Osteogênese , Nanofibras/química , Hidrogéis/farmacologia , Regeneração Óssea , Alicerces Teciduais/química , Engenharia Tecidual/métodos
3.
ACS Omega ; 8(11): 10030-10039, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36969465

RESUMO

Chronic diabetic wounds have become a significant cause of disability worldwide. It is highly desired to develop effective therapies that can promote the rapid healing of diabetic wounds. Owing to the outstanding hydrophilic and water-retaining properties, hydrogels could accelerate the healing process. Extracellular vesicles (EVs) have shown the ability to promote cell regeneration and angiogenesis. In this study, we chose a gelatin methacryloyl (GelMA) hydrogel, a kind of biomaterial characteristic of good biocompatibility, to load the EVs derived from umbilical cord mesenchymal stem cells (UCMSCs) in order to have a long-lasting effect by consistent release of EVs. Then, the hydrogel with EVs was used to treat diabetic wounds in rat models. Nuclear magnetic resonance spectroscopy and scanning electron microscopy were used to characterize the synthesis of the hydrogel; cell experiments, animal experiments, and histological staining were used to evaluate the function of the hydrogel with EVs. The results show that the GelMA hydrogel incorporated with the UCMSC-derived EVs exhibits unique physicochemical properties, excellent biocompatibility, and much enhanced therapeutic effects for diabetic wounds.

4.
Adv Healthc Mater ; 12(18): e2203131, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36854163

RESUMO

Extracellular vesicles (EVs) play an important role in intercellular communication, and the function of EVs mainly depends on the state of source cells. To determine the effect of diabetic microenvironment on EVs secreted by bone marrow mesenchymal stem cells (BMSCs), this work explores the effect of normal glucose (5.5 mm) cultured BMSCs derived EVs (NG-EVs) and high glucose (30 mm) cultured BMSCs derived EVs (HG-EVs) in regulating the migration, proliferation and osteoblastic differentiation of BMSCs in vitro. In order to improve the bioavailability of EVs, this work constructs a sustained release system of polydopamine (PDA) functionalized 3D printing gelatin/hyaluronic acid/nano-hydroxyapatite (Gel/HA/nHAP) scaffolds (S/PDA) and verifies its function in the calvarial defect model of diabetic rats. This work confirms that both NG-EVs and HG-EVs can promote proliferation and migration, inhibit apoptosis and promote osteogenic differentiation, but the function of HG-EVs is weaker than that of NG-EVs. Therefore, EVs secreted by autologous cells of diabetic patients are not suitable for self-repair. This work hopes that the 3D printing scaffold designed for sustained-release EVs will provide a new strategy for acellular tissue engineering bone repair in diabetic patients.


Assuntos
Diabetes Mellitus Experimental , Vesículas Extracelulares , Ratos , Animais , Osteogênese , Gelatina/farmacologia , Ácido Hialurônico/farmacologia , Preparações de Ação Retardada/farmacologia , Durapatita/farmacologia , Alicerces Teciduais , Regeneração Óssea/fisiologia , Diferenciação Celular , Glucose/farmacologia , Impressão Tridimensional
5.
Biomater Sci ; 11(7): 2445-2460, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36757828

RESUMO

Macrophages play a distinctive role in the early stage of inflammation after cartilage defects. Previous studies have shown that macrophages can express different phenotypes, among which M2 polarization is important to maintain the balance of the inflammatory microenvironment and promote cartilage regeneration. In this study, 4-octyl itaconic acid (4-OI), a derivative of the endogenous metabolite itaconic acid, was used to regulate the polarization behavior of macrophages and enhance cartilage repair. Oxidized sodium alginate (OSA) and gelatin (GEL) were selected as materials to form injectable hydrogels with the function of sustained release of 4-OI. In vivo and in vitro experiments have verified that the OSA/GEL hydrogel system loaded with 4-OI could promote M2 macrophage polarization and inhibit the inflammatory reaction. A rat knee joint cartilage defect model further confirmed its role in promoting cartilage regeneration in the later stage. In this study, the OSA/GEL hydrogel was successfully fabricated as a vehicle for delivering 4-OI, which could evidently alleviate the inflammatory reaction and thus accelerate tissue regeneration. The results of this study provide a new method for promoting subsequent tissue regeneration by regulating the early immune response.


Assuntos
Cartilagem , Hidrogéis , Macrófagos , Animais , Ratos , Gelatina/metabolismo , Hidrogéis/farmacologia , Inflamação/metabolismo , Polaridade Celular , Regeneração
6.
Int J Biol Macromol ; 226: 1192-1202, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36442556

RESUMO

Acute kidney injury (AKI) is a pathological process with high morbidity, and drug resistance is easy to occur due to untargeted drug therapy. Curcumin can repair acute kidney injury. The expression of the CD44 receptor in renal tubular epithelial cells is abnormally elevated during AKI, and hyaluronic acid (HA) has the ability to bind specifically to the CD44 receptor. In this study, we developed a hyaluronic acid-coated liposome (HALP) nanocomplexes that targeted renal epithelial cells and its effect of relieving AKI was investigated. HALP was formed by self-assembly through the electrostatic interaction of curcumin-loaded cationic liposomes (LP) with hyaluronic acid and responds to the release of curcumin in the acidic microenvironment of lesions to treat AKI. HALP had good stability and biocompatibility. The in vitro results showed that compared to LP, HALP exhibited higher antioxidant, anti-inflammatory, and anti-apoptotic capacities. The AKI model suggested that HALP could not only target and accumulate in the injured kidney but also had an excellent ability to reduce the inflammatory response, which decreased tubular necrosis and restored kidney function.


Assuntos
Injúria Renal Aguda , Curcumina , Humanos , Curcumina/farmacologia , Curcumina/uso terapêutico , Ácido Hialurônico/uso terapêutico , Lipossomos/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo
7.
Front Oncol ; 12: 929949, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36226070

RESUMO

Morphological changes that may arise through a treatment course are probably one of the most significant sources of range uncertainty in proton therapy. Non-invasive in-vivo treatment monitoring is useful to increase treatment quality. The INSIDE in-beam Positron Emission Tomography (PET) scanner performs in-vivo range monitoring in proton and carbon therapy treatments at the National Center of Oncological Hadrontherapy (CNAO). It is currently in a clinical trial (ID: NCT03662373) and has acquired in-beam PET data during the treatment of various patients. In this work we analyze the in-beam PET (IB-PET) data of eight patients treated with proton therapy at CNAO. The goal of the analysis is twofold. First, we assess the level of experimental fluctuations in inter-fractional range differences (sensitivity) of the INSIDE PET system by studying patients without morphological changes. Second, we use the obtained results to see whether we can observe anomalously large range variations in patients where morphological changes have occurred. The sensitivity of the INSIDE IB-PET scanner was quantified as the standard deviation of the range difference distributions observed for six patients that did not show morphological changes. Inter-fractional range variations with respect to a reference distribution were estimated using the Most-Likely-Shift (MLS) method. To establish the efficacy of this method, we made a comparison with the Beam's Eye View (BEV) method. For patients showing no morphological changes in the control CT the average range variation standard deviation was found to be 2.5 mm with the MLS method and 2.3 mm with the BEV method. On the other hand, for patients where some small anatomical changes occurred, we found larger standard deviation values. In these patients we evaluated where anomalous range differences were found and compared them with the CT. We found that the identified regions were mostly in agreement with the morphological changes seen in the CT scan.

8.
Heliyon ; 8(8): e09975, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35936234

RESUMO

Analysis of the atmospheric Aerosol Particle Size Distribution (APSD) retrieved from Light Detection and Ranging (Lidar) data is one of the popular fields in atmospheric remote sensing. An APSD retrieval method based on the lognormal particle size distribution, the Mie theory, and the Second Simulation of the Satellite Signal in the Solar Spectrum (6S) were studied. According to the 6S, this method divides the main body of the aerosols into four basic components and calculates the APSD from Lidar data and the optical and microphysical characteristics of these components. Numerical simulation and experimental observations reveal that this method can obtain the APSD for particle sizes of >0.15 µm in the different vertical layers with good reliability.

9.
Small ; 18(16): e2107354, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35277920

RESUMO

Small extracellular vesicles (sEVs) secreted by mesenchymal stem cells (MSCs) have been extensively studied in recent years. sEV contents change with the secreting cell state. When MSCs are exposed to an inflammatory environment, they release more functional growth factors, exosomes, and chemokines. Herein, MSCs are stimulated to alter sEV cargos and functions to regulate the inflammatory microenvironment and promote tissue regeneration. Sequencing of sEV miRNAs shows that certain RNAs conducive to cell function are upregulated. In this study, in vitro cell function experiments show that both inflammation-stimulated adipose-derived MSC (ADSC)-derived sEV (IAE) and normal ADSC-derived sEV (AE) promote cell proliferation; IAE also significantly improves cell migration. Regarding macrophage polarization regulation, IAE significantly promotes M2 macrophage differentiation. RNA-sequencing analysis indicates that high miR-27b-3p expression levels in IAE may regulate macrophages by targeting macrophage colony-stimulating factor-1 (CSF-1). In vivo, a rabbit temporomandibular joint (TMJ) condylar osteochondral defect model shows that both AE and IAE promote TMJ regeneration, with IAE having the most significant therapeutic effect. Therefore, the authors confirm that exposing MSCs to an inflammatory environment can feasibly enhance sEV functions and that modified sEVs achieve better therapeutic effects.


Assuntos
Vesículas Extracelulares , MicroRNAs , Animais , Vesículas Extracelulares/metabolismo , Inflamação/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Macrófagos , MicroRNAs/genética , MicroRNAs/metabolismo , Coelhos , Articulação Temporomandibular
10.
Med Phys ; 49(1): 23-40, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34813083

RESUMO

PURPOSE: In-beam positron emission tomography (PET) is one of the modalities that can be used for in vivo noninvasive treatment monitoring in proton therapy. Although PET monitoring has been frequently applied for this purpose, there is still no straightforward method to translate the information obtained from the PET images into easy-to-interpret information for clinical personnel. The purpose of this work is to propose a statistical method for analyzing in-beam PET monitoring images that can be used to locate, quantify, and visualize regions with possible morphological changes occurring over the course of treatment. METHODS: We selected a patient treated for squamous cell carcinoma (SCC) with proton therapy, to perform multiple Monte Carlo (MC) simulations of the expected PET signal at the start of treatment, and to study how the PET signal may change along the treatment course due to morphological changes. We performed voxel-wise two-tailed statistical tests of the simulated PET images, resembling the voxel-based morphometry (VBM) method commonly used in neuroimaging data analysis, to locate regions with significant morphological changes and to quantify the change. RESULTS: The VBM resembling method has been successfully applied to the simulated in-beam PET images, despite the fact that such images suffer from image artifacts and limited statistics. Three dimensional probability maps were obtained, that allowed to identify interfractional morphological changes and to visualize them superimposed on the computed tomography (CT) scan. In particular, the characteristic color patterns resulting from the two-tailed statistical tests lend themselves to trigger alarms in case of morphological changes along the course of treatment. CONCLUSIONS: The statistical method presented in this work is a promising method to apply to PET monitoring data to reveal interfractional morphological changes in patients, occurring over the course of treatment. Based on simulated in-beam PET treatment monitoring images, we showed that with our method it was possible to correctly identify the regions that changed. Moreover we could quantify the changes, and visualize them superimposed on the CT scan. The proposed method can possibly help clinical personnel in the replanning procedure in adaptive proton therapy treatments.


Assuntos
Terapia com Prótons , Humanos , Método de Monte Carlo , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
11.
Biomolecules ; 11(5)2021 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066859

RESUMO

Diabetic foot wound healing is a major clinical problem due to impaired angiogenesis and bacterial infection. Therefore, an effective regenerative dressing is desiderated with the function of promoting revascularization and anti-bacteria. Herein, a multifunctional injectable composite hydrogel was prepared by incorporation of the cerium-containing bioactive glass (Ce-BG) into Gelatin methacryloyl (GelMA) hydrogel. The Ce-BG was synthesized by combining sol-gel method with template method, which maintained spherical shape, chemical structure and phase constitution of bioactive glass (BG). The Ce-BG/GelMA hydrogels had good cytocompatibility, promoted endothelial cells migration and tube formation by releasing Si ion. In vitro antibacterial tests showed that 5 mol % CeO2-containing bioactive glass/GelMA (5/G) composite hydrogel exhibited excellent antibacterial properties. In vivo study demonstrated that the 5/G hydrogel could significantly improve wound healing in diabetic rats by accelerating the formation of granulation tissue, collagen deposition and angiogenesis. All in all, these results indicate that the 5/G hydrogel could enhance diabetic wound healing. Therefore, the development of multifunctional materials with antibacterial and angiogenic functions is of great significance to promote the repair of diabetic wound healing.


Assuntos
Antibacterianos/administração & dosagem , Cério/administração & dosagem , Diabetes Mellitus Experimental/complicações , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Cério/química , Cério/farmacologia , Colágeno/metabolismo , Diabetes Mellitus Experimental/metabolismo , Gelatina/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Hidrogéis , Nanopartículas Metálicas , Metacrilatos/química , Camundongos , Ratos , Estreptozocina/efeitos adversos
12.
Front Oncol ; 11: 601784, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178614

RESUMO

Particle therapy in which deep seated tumours are treated using 12C ions (Carbon Ions RadioTherapy or CIRT) exploits the high conformity in the dose release, the high relative biological effectiveness and low oxygen enhancement ratio of such projectiles. The advantages of CIRT are driving a rapid increase in the number of centres that are trying to implement such technique. To fully profit from the ballistic precision achievable in delivering the dose to the target volume an online range verification system would be needed, but currently missing. The 12C ions beams range could only be monitored by looking at the secondary radiation emitted by the primary beam interaction with the patient tissues and no technical solution capable of the needed precision has been adopted in the clinical centres yet. The detection of charged secondary fragments, mainly protons, emitted by the patient is a promising approach, and is currently being explored in clinical trials at CNAO. Charged particles are easy to detect and can be back-tracked to the emission point with high efficiency in an almost background-free environment. These fragments are the product of projectiles fragmentation, and are hence mainly produced along the beam path inside the patient. This experimental signature can be used to monitor the beam position in the plane orthogonal to its flight direction, providing an online feedback to the beam transverse position monitor chambers used in the clinical centres. This information could be used to cross-check, validate and calibrate, whenever needed, the information provided by the ion chambers already implemented in most clinical centres as beam control detectors. In this paper we study the feasibility of such strategy in the clinical routine, analysing the data collected during the clinical trial performed at the CNAO facility on patients treated using 12C ions and monitored using the Dose Profiler (DP) detector developed within the INSIDE project. On the basis of the data collected monitoring three patients, the technique potential and limitations will be discussed.

13.
J Biomed Mater Res B Appl Biomater ; 109(11): 1724-1734, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33739603

RESUMO

Hypertrophic scar, a common skin disorder typically caused by deep burns or scald were usually treated via surgical resection, laser irradiation, and drugs. However, all the approaches were always companied with complications and devastatingly subjected to relapse, which indicated the urgently need of an effective treatment method. In this project, a new hydrogel composed of Poly (γ-glutamic acid) (γ-PGA), Chitooligo-saccharide, and Papain was developed via crosslinker (EDC&NHS), and characterized with good porously three-dimensional network structure, good water absorption, and mechanical properties. Besides, G/C/P hydrogel facilitated cell adhesion and inhibited excessive proliferation of fibroblasts, which indicated the potential of in vivo application. After applied onto skin wound healing in vivo on a rabbit ear skin wound model, G/C/P hydrogel inhibited excessive collagen deposition and the generation of hyperplastic scars effectively during wound healing. The hydrogel described here provide a new platform for regeneration field and hold great promise for solving serious skin disorder.


Assuntos
Quitosana , Cicatriz Hipertrófica , Hidrogéis , Oligossacarídeos , Papaína , Ácido Poliglutâmico , Cicatrização/efeitos dos fármacos , Animais , Quitosana/química , Quitosana/farmacologia , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/prevenção & controle , Feminino , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Células NIH 3T3 , Oligossacarídeos/química , Oligossacarídeos/farmacologia , Papaína/química , Papaína/farmacologia , Ácido Poliglutâmico/química , Ácido Poliglutâmico/farmacologia , Coelhos
14.
Front Oncol ; 11: 777852, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35024354

RESUMO

Different therapies are adopted for the treatment of deep seated tumours in combination or as an alternative to surgical removal or chemotherapy: radiotherapy with photons (RT), particle therapy (PT) with protons or even heavier ions like 12C, are now available in clinical centres. In addition to these irradiation modalities, the use of Very High Energy Electron (VHEE) beams (100-200 MeV) has been suggested in the past, but the diffusion of that technique was delayed due to the needed space and budget, with respect to standard photon devices. These disadvantages were not paired by an increased therapeutic efficacy, at least when comparing to proton or carbon ion beams. In this contribution we investigate how recent developments in electron beam therapy could reshape the treatments of deep seated tumours. In this respect we carefully explored the application of VHEE beams to the prostate cancer, a well-known and studied example of deep seated tumour currently treated with high efficacy both using RT and PT. The VHEE Treatment Planning System was obtained by means of an accurate Monte Carlo (MC) simulation of the electrons interactions with the patient body. A simple model of the FLASH effect (healthy tissues sparing at ultra-high dose rates), has been introduced and the results have been compared with conventional RT. The study demonstrates that VHEE beams, even in absence of a significant FLASH effect and with a reduced energy range (70-130 MeV) with respect to implementations already explored in literature, could be a good alternative to standard RT, even in the framework of technological developments that are nowadays affordable.

15.
BMC Geriatr ; 20(1): 533, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33302877

RESUMO

BACKGROUND: For older adults, difficulties in bathing and toileting are often the most prevalent in the index of Activities of daily living (ADL). This study aims to examine how environmental factors are associated with difficulty of bathing and toileting among older adults in rural China. METHOD: The data are from the 2014 Thousand-Village Survey (TVS), a national survey of Chinese rural residents of old age. The sample consists of 10,689 subjects, 55 years or older, from 536 villages across all provinces of China. Logistic regressions were applied to examine how difficulty of bathing and toileting was related to environmental factors such as geographic location, neighbourhood amenity, and related facilities of bathing and toileting. RESULTS: Older adults living in the Southern regions of China had lesser difficulty in bathing and toileting than those living in Northern China, controlling for other confounders. Better neighbourhood conditions also reduced the likelihood of having such disabilities. Persons who bathed indoors without showering facilities, in public facilities, and outdoors were significantly more likely to have bathing disability than those who showered indoors with facility. Rural older adults who used pedestal pans and indoor buckets for toileting were more likely to have toileting disability than those who used indoor squatting facilities. CONCLUSION: Environmental barriers were associated with functional disability among older adults in rural China, but the disabled individuals may change their environments to adapt to their functional capabilities. Our findings suggest that it is imperative to promote the use of showering facilities and pedestal pans for toileting in rural China.


Assuntos
Atividades Cotidianas , Pessoas com Deficiência , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Rural , Autocuidado
16.
Orthop Surg ; 12(3): 938-945, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32462800

RESUMO

OBJECTIVE: To explore the effect of kartogenin (KGN) on proliferation and chondrogenic differentiation of human umbilical cord mesenchymal stem cells (hUCMSC) in vitro, and the synergistic effects of KGN and transforming growth factor (TGF)-ß3 on hUCMSC. METHODS: Human umbilical cord mesenchymal stem cells were isolated and cultured. Then the differentiation properties were identified by flow cytometry analysis. HUCMSC were divided into four groups: control group, KGN group, TGF-ß3 group, and TK group (with TGF-ß3 and KGN added into the medium simultaneously). Cells in all groups were induced for 21 days using the suspension ball culture method. Hematoxylin and eosin, immunofluorescence, and Alcian blue staining were used to analyze chondrogenic differentiation. Real-time reverse transcriptase polymerase chain reaction was performed to investigate genes associated with chondrogenic differentiation. RESULT: Hematoxylin and eosin staining showed that cells in the TGF-ß3 group and the TK group had formed cartilage-like tissue after 21 days of culture. The results of immunofluorescence and Alcian blue staining showed that compared with the control group, cells in the KGN and TGF-ß3 groups demonstrated increased secretion of aggrecan after 21 days of culture. In addition, cells in the group combining KGN with TGF-ß3 (5.587 ± 0.27, P < 0.01) had more collagen II secretion than cells in the TGF-ß3 alone group (2.86 ± 0.141, P < 0.01) or the KGN group (1.203 ± 0.215, P < 0.01). The expression of aggrecan (2.468 ± 0.097, P < 0.05) and SRY-Box 9 (4.08 ± 0.13, P < 0.05) in cells in the group combining KGN with TGF-ß3 was significantly higher than those in the TGF-ß3 group (2.216 ± 0.09, 3.02 ± 0.132, P < 0.05).' CONCLUSION: The combination of KGN and TGF-ß3 had synergistic effects and induced hUCMSC chondrogenesis. This could represent a new approach for clinical application and studies on cartilage repair and regeneration.


Assuntos
Anilidas/farmacologia , Condrogênese , Células-Tronco Mesenquimais/citologia , Ácidos Ftálicos/farmacologia , Fator de Crescimento Transformador beta3/farmacologia , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Cordão Umbilical/citologia
17.
Opt Express ; 28(9): 13786-13800, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32403846

RESUMO

The differential absorption lidar (DIAL) has been proposed as an effective method for detecting polluted gases in the atmosphere. In this paper, we present a compact and movable ozone differential absorption (O3-DIAL) based on an all-solid-state and tuning-free laser source. For the first time, solid-state stimulated Raman scattering technology is used in the emitting source of the lidar for wavelength conversion. A high repetition frequency Innoslab laser is used for pumping SrWO4 crystals to get yellow lasers which can achieve up to 70% light-to-light conversion efficiency. Our results demonstrate that using the SrWO4 crystal as the Raman frequency-shifting media of the lidar laser source for obtaining the vertical profiles of tropospheric ozone in the Planetary Boundary Layer (PBL) is a suitable choice. As a compact movable lidar system, the results demonstrate the reliability and stability.

18.
Mater Sci Eng C Mater Biol Appl ; 109: 110618, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228889

RESUMO

Periodontal disease is a common complication and conventional periodontal surgery can lead to severe bleeding. Guided tissue regeneration (GTR) membranes favor periodontal regrowth, but they still have limitations, such as improper biodegradation, poor mechanical property, and no effective hemostatic property. To overcome these shortcomings, we generated unique multifunctional scaffolds. A chitosan/polycaprolactone/gelatin sandwich-like construction was fabricated by electrospinning and lyophilization. These composite scaffolds showed favorable physicochemical properties, including: appropriate porosity (<50%), pore size (about 10 µm) and mechanical stability (increasing with more PCL), good swelling and hydrophilicity. Appropriate degradation rates were approved by degradability analysis in vitro and in vivo, which resembled tissue regeneration process more closely. As shown in cell viability assay, cell attachment assay and Sirius red staining, we knew that the scaffolds had good biocompatibility, did not adversely affect cell ability for attachment, and induced high levels of collagen secretion. Experiments of blood clotting measurement in vitro showed that composite scaffolds were capable of accelerating blood clotting and could realize effective hemostasis. The results from subcutaneous implantation revealed the scaffolds had strong cell barrier effects and protection from external cell invasion. In summary, our multifunctional composite scaffolds showed optimised structure, enhanced regenerative capabilities, and serve as a basis for approaches to improve GTR designs for periodontal regeneration.


Assuntos
Quitosana , Gelatina , Teste de Materiais , Membranas Artificiais , Periodonto/fisiologia , Poliésteres , Regeneração/efeitos dos fármacos , Células 3T3 , Animais , Quitosana/química , Quitosana/farmacologia , Gelatina/química , Gelatina/farmacologia , Masculino , Camundongos , Periodonto/lesões , Periodonto/metabolismo , Poliésteres/química , Poliésteres/farmacologia , Porosidade , Ratos , Ratos Sprague-Dawley
19.
Int J Nanomedicine ; 15: 1939-1950, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256070

RESUMO

INTRODUCTION: Chronic trauma repair is an important issue affecting people's healthy lives. Thermo-sensitive hydrogel is injectable in situ and can be used to treat large-area wounds. In addition, antioxidants play important roles in promoting wound repair. METHODS: The purpose of this research was to prepare a novel thermo-sensitive hydrogel-poly(N-isopropyl-acrylamide)/poly(γ-glutamic acid) (PP) loaded with superoxide dismutase (SOD) to improve the effect for trauma treatment. The micromorphology of the hydrogel was observed by scanning electron microscope and the physical properties were measured. The biocompatibility of hydrogel was evaluated by MTT experiment, and the effect of hydrogel on skin wound healing was evaluated by in vivo histological staining. RESULTS: Gelling behavior and differential scanning calorimeter outcomes showed that the PP hydrogels possessed thermo-sensitivity at physiological temperature and the phase transformation temperature was 28.2°C. The high swelling rate and good water retention were conducive to wound healing. The activity of SOD in vitro was up to 85% at 10 h, which was advantageous to eliminate the superoxide anion. MTT assay revealed that this hydrogel possessed good biocompatibility. Dressings of PP loaded with SOD (SOD-PP) had a higher wound closure rate than other treatments in vivo in diabetic rat model. DISCUSSION: The SOD-PP thermo-sensitive hydrogels can effectively promote wound healing and have good application prospects for wound repair.


Assuntos
Bandagens , Hidrogéis/química , Hidrogéis/farmacologia , Superóxido Dismutase/administração & dosagem , Superóxido Dismutase/farmacologia , Cicatrização/efeitos dos fármacos , Resinas Acrílicas/química , Animais , Materiais Biocompatíveis/química , Diabetes Mellitus Experimental/fisiopatologia , Masculino , Teste de Materiais , Ácido Poliglutâmico/química , Polímeros/química , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Temperatura
20.
Sci Total Environ ; 713: 136651, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31955108

RESUMO

Sediment containing numerous nutrients and pollutants has become an important consideration when treating black-odor water. Excessive activated sludge produced in wastewater treatment plants contains a large number of microorganisms, which is beneficial for removing organics and nutrients from the black-odor sediment. In this study, three types of sludge from a secondary sedimentation tank (SST), a digestion tank (DT), and an aerobic tank treating landfill leachate (AT_leachate) were used to treat black-odor sediment, respectively. All the three types of activated sludge enhanced the treatment performance of sediment. The SST sludge worked the best with the optimal dosage of 2.56 g/(kg sediment), and the removal of nitrogen and organics reached 57.03 and 28.14%, respectively. Illumina MiSeq sequencing revealed that the activated sludge significantly affected the microbial community of the sediment. In particular, SST sludge resulted in significant increase in the number of microorganisms related to nitrification and sulfur metabolism to 10.68 and 10.97%, respectively. This was found to be important for degrading organics and promoting nitrogen removal. This study provides an efficient strategy for the treatment of black-odor sediment, and also realizes the complete utilization of waste activated sludge.


Assuntos
Esgotos , Reatores Biológicos , Nitrificação , Nitrogênio , Odorantes , Eliminação de Resíduos Líquidos , Águas Residuárias , Água , Poluentes Químicos da Água
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