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1.
Nano Lett ; 24(29): 8996-9003, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38995813

RESUMO

Interventional therapy is widely regarded as a highly promising treatment approach for nonsurgical liver cancer. However, the development of drug resistance and tolerance to hypoxic environments after embolization can lead to increased angiogenesis, enhanced tumor cell stemness, and greater invasiveness, resulting in metastasis and recurrence. To address these challenges, a novel approach involving the use of lecithin and DSPE-PEG comodified Ca2+ loaded (NH4)2S2O8 (LDCNSO) drug in combination with transcatheter arterial embolization (TAE) has been proposed. The sono-blasting effect of LDCNSO under ultrasound triggers a cascading amplification of oxidative stress, by releasing sulfate radical (·SO4-), hydroxyl radical (·OH), and superoxide (·O2-), inducing Ca2+ overload, and reducing glutathione (GSH) levels, which eventually leads to apoptosis. LDCNSO alongside TAE has demonstrated remarkable therapeutic efficacy in the rabbit orthotopic cancer model, resulting in significant inhibition of tumor growth. This research provides valuable insights for the effective treatment of orthotopic tumors.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Estresse Oxidativo , Animais , Estresse Oxidativo/efeitos dos fármacos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/tratamento farmacológico , Humanos , Coelhos , Apoptose/efeitos dos fármacos , Embolização Terapêutica/métodos , Linhagem Celular Tumoral , Glutationa/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico
2.
Small ; 20(28): e2400165, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38329189

RESUMO

Biomimetic tactile nervous system (BTNS) inspired by organisms has motivated extensive attention in wearable fields due to its biological similarity, low power consumption, and perception-memory integration. Though many works about planar-shape BTNS are developed, few researches could be found in the field of fibrous BTNS (FBTNS) which is superior in terms of strong flexibility, weavability, and high-density integration. Herein, a FBTNS with multimodal sensibility and memory is proposed, by fusing the fibrous poly lactic acid (PLA)/Ag/MXene/Pt artificial synapse and MXene/EMIMBF4 ionic conductive elastomer. The proposed FBTNS can successfully perceive external stimuli and generate synaptic responses. It also exhibits a short response time (23 ms) and low set power consumption (17 nW). Additionally, the proposed device demonstrates outstanding synaptic plasticity under both mechanical and electrical stimuli, which can simulate the memory function. Simultaneously, the fibrous devices are embedded into textiles to construct tactile arrays, by which biomimetic tactile perception and temporary memory functions are successfully implemented. This work demonstrates the as-prepared FBTNS can generate biomimetic synaptic signals to serve as artificial feeling signals, it is thought that it could offer a fabric electronic unit integrating with perception and memory for Human-Computer interaction, and has great potential to build lightweight and comfortable Brain-Computer interfaces.


Assuntos
Biomimética , Sinapses , Biomimética/métodos , Sinapses/fisiologia , Tato/fisiologia , Memória/fisiologia , Materiais Biomiméticos/química , Humanos , Poliésteres/química
3.
Med Sci Monit ; 30: e942832, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321725

RESUMO

BACKGROUND Hypertriglyceridemia-induced acute pancreatitis (HTG-AP), representing 10% of all acute pancreatitis cases, is characterized by younger onset age and more severe progression, often leading to higher ICU admission rates. This condition poses a significant challenge due to its rapid progression and the potential for severe complications, including multiple organ failure. HTG-AP is distinct from other forms of pancreatitis, such as those caused by cholelithiasis or alcohol, in terms of clinical presentation and outcomes. It's essential to identify early markers that can predict the severity of HTG-AP to improve patient management and outcomes. MATERIAL AND METHODS This study divided 127 HTG-AP patients into mild acute pancreatitis (MAP, n=71) and moderate-to-severe acute pancreatitis (MSAP/SAP, n=56) groups. Blood biological indicators within the first 24 hours of admission were analyzed. Risk factors for HTG-AP progression were determined using binary logistic regression and ROC curves. RESULTS Elevated levels of HCT, NLR, TBI, DBI, AST, Cre, and AMS were noted in the MSAP/SAP group, with lower levels of LYM, Na⁺, Ca²âº, ApoA, and ApoB compared to the MAP group (p<0.05). NEUT%, Ca²âº, ApoA, and ApoB were significantly linked with HTG-AP severity. Their combined ROC analysis yielded an area of 0.81, with a sensitivity of 61.8% and specificity of 90%. CONCLUSIONS NEUT%, Ca²âº, ApoA, and ApoB are significant risk factors for progressing to MSAP/SAP in HTG-AP. Their combined assessment provides a reliable predictive measure for early intervention in patients at risk of severe progression.


Assuntos
Hipertrigliceridemia , Pancreatite , Humanos , Cálcio , Neutrófilos , Doença Aguda , Estudos Retrospectivos , Hipertrigliceridemia/complicações , Apolipoproteínas , Apolipoproteínas A , Apolipoproteínas B
4.
Eur Spine J ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869649

RESUMO

PURPOSE: To evaluate different patterns of coronal deformity secondary to ankylosing spondylitis (AS), to propose relevant treatment strategies, and to assess efficacy of asymmetrical pedicle subtraction osteotomy (APSO). METHODS: Coronal deformity was defined as coronal Cobb angle over 20º or coronal balance distance (CBD) more than 3 cm. 65 consecutive AS patients with concomitant coronal and sagittal deformity who underwent PSO were included. The average follow-up time was 40.4 months. Radiographic evaluation included coronal Cobb angle and CBD. Furthermore, sagittal parameters were used to assess magnitude and maintenance of kyphosis correction. RESULTS: Based on curve characteristics, coronal deformity caused by AS included four different radiologic patterns: Pattern I: lumbar scoliosis; Pattern II: C-shaped thoracolumbar curve; Pattern III: trunk shift without major curve; Pattern IV: proximal thoracic scoliosis. APSO was performed for patients in Pattern I to III while conventional PSO was applied for patients in Pattern IV. Significant improvement in all the sagittal parameters were noted in 65 patients without obvious correction loss at the last follow-up. Besides, significant and sustained correction of coronal mal-alignment was identified in 59 APSO-treated patients. Rod fracture occurred in four cases and revision surgery was performed for one case. CONCLUSION: According to radiologic manifestations, coronal deformity caused by AS could be categorized into four patterns. APSO proved to be a feasible and effective procedure for correction of Pattern I to III patients. Coronal deformity pattern, apex location, sagittal profile of lumbar spine and preoperative hip function should be considered for osteotomy level selection in APSO.

5.
Nano Lett ; 23(8): 3418-3425, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37042745

RESUMO

Lead halide perovskites have been promising platforms for micro- and nanolasers. However, the fragile nature of perovskites poses an extreme challenge to engineering a cavity boundary and achieving high-quality (Q) modes, severely hindering their practical applications. Here, we combine an etchless bound state in the continuum (BIC) and a chemically synthesized single-crystalline CsPbBr3 microplate to demonstrate on-chip integrated perovskite microlasers with ultrahigh Q factors. By pattering polymer microdisks on CsPbBr3 microplates, we show that record high-Q BIC modes can be formed by destructive interference between different in-plane radiation from whispering gallery modes. Consequently, a record high Q-factor of 1.04 × 105 was achieved in our experiment. The high repeatability and high controllability of such ultrahigh Q BIC microlasers have also been experimentally confirmed. This research provides a new paradigm for perovskite nanophotonics.

6.
Small ; 19(28): e2208243, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37191327

RESUMO

Inverted perovskite solar cells (IPSCs) have witnessed an impressive development in recent years. However, their efficiency is still significantly behind theoretical limits, and device instabilities hinder their commercialization. Two main obstacles to further enhancing their performance via one-step deposition are: 1) the unsatisfactory film quality of perovskite and 2) the poor surface contact. To address the above issues, 4-butanediol ammonium Bromide (BD) is utilized to passivate Pb2+ defects by forming PbN bonds and fill vacancies of formamidinium ions at the buried surface of perovskite. The wettability of poly [bis (4-phenyl) (2,4,6-triMethylphenyl) amine] films is also improved due to the formation of hydrogen bonds between PTAA and BD molecules, resulting in better surface contacts and enhanced perovskite crystallinity. As a result, BD-modified perovskite thin films show a significant increase in the mean grain size, as well as a dramatic enhancement in the PL decay lifetime. The BD-treated device exhibits an efficiency of up to 21.26%, considerably higher than the control device. Moreover, the modified devices show dramatically enhanced thermal and ambient stability compared to the control ones. This methodology paves the way to obtain high-quality perovskite films for fabricating high-performance IPSCs.

7.
Rev Cardiovasc Med ; 24(9): 260, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39076386

RESUMO

Background: While both cystatin C and left ventricular ejection fraction (LVEF) revealed established prognostic efficacy in coronary artery disease (CAD), the relationship between cystatin C/left ventricular ejection fraction ratio (CLR) and adverse clinical outcomes among patients with CAD following percutaneous coronary intervention (PCI) remains obscure, to date. Therefore, we sought to assess the predictive efficacy of CLR among CAD patients who underwent PCI in current study. Methods: A total of 14,733 participants, including 8622 patients with acute coronary syndrome (ACS) and 6111 patients with stable coronary artery disease (SCAD), were enrolled from a prospective cohort of 15,250 CAD patients who underwent PCI and were admitted to the First Affiliated Hospital of Xinjiang Medical University from 2016 to 2021. The primary outcome of this study was mortality, including all-cause mortality (ACM) and cardiac mortality (CM). The secondary outcomes were major adverse cardiovascular events (MACEs), major adverse cardiac and cerebrovascular events (MACCEs) and nonfatal myocardial infarction (NFMI). For CLR, the optimal cut-off value was determined by utilizing receiver operating characteristic curve analysis (ROC). Subsequently, patients were assigned into two groups: a high-CLR group (CLR ≥ 0.019, n = 3877) and a low-CLR group (CLR < 0.019, n = 10,856), based on optimal cut-off value of 0.019. Lastly, the incidence of outcomes between the two groups was compared. Results: The high-CLR group had a higher incidence of ACM (8.8% vs. 0.9%), CM (6.7% vs. 0.6%), MACEs (12.7% vs. 5.9%), MACCEs (13.3% vs. 6.7%), and NFMIs (3.3% vs. 0.9%). After adjusting for confounders, multivariate Cox regression analyses revealed that patients with high-CLR had an 8.163-fold increased risk of ACM (HR = 10.643, 95% CI: 5.525~20.501, p < 0.001), a 10.643-fold increased risk of CM (HR = 10.643, 95% CI: 5.525~20.501, p < 0.001), a 2.352-fold increased risk of MACE (HR = 2.352, 95% CI: 1.754~3.154, p < 0.001), a 2.137-fold increased risk of MACCEs (HR = 2.137, 95% CI: 1.611~2.834, p < 0.001), and a 1.580-fold increased risk of NFMI (HR = 1.580, 95% CI: 1.273~1.960, p < 0.001) compared to patients with low-CLR. Conclusions: The current study indicated that a high CLR is a novel and powerful predictor of adverse long-term outcomes in CAD patients who underwent PCI, and that, it is a better predictor for patients wtih SCAD and ACS. Clinical Trial Registration: NCT05174143, http://Clinicaltrials.gov.

8.
J Sep Sci ; 45(15): 2924-2934, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35699087

RESUMO

Hawthorn, one of the widely-used Chinese herbal medicines, has been used to treat blood stasis syndrome in the clinic, but its blood-activating components are unclear. This study combined the ultra-high-performance liquid chromatography-quadruple exactive-orbitrap mass spectrometry with chemometrics to identify the blood-activating components of hawthorn. Different polar fractions of hawthorn aqueous extracts were extracted and mixed to prepare 14 samples. The contents of 25 chemical components for 14 samples were determined by the proposed quantitative method which was validated in terms of linearity, precision, stability, repeatability, and recovery, while the blood-activating effect was evaluated by measuring the whole blood viscosity, plasma viscosity, and plasma fibrinogen levels. Then the partial least squares model was established on the spectrum-effect relationship. The result showed that vitexin-2″-O-rhamnoside, rutin, citric acid, malic acid, gallic acid, and fumaric acid could reduce the whole blood viscosity, plasma viscosity, and plasma fibrinogen levels in blood stasis model rats, and these components were the blood-activating components of hawthorn. This study provided a scientific basis for clarifying the blood-activating components of hawthorn, and the spectrum-effect approach proved to be an effective approach to discovering the bioactive components of Chinese herbal medicines.


Assuntos
Crataegus , Medicamentos de Ervas Chinesas , Animais , Quimiometria , Cromatografia Líquida de Alta Pressão/métodos , Crataegus/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Fibrinogênio , Ratos , Espectrometria de Massas em Tandem/métodos
9.
J Sep Sci ; 45(11): 1839-1846, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35318796

RESUMO

Hawthorn, one of the widely-used traditional Chinese medicines, has been used to treat dyspepsia, hyperlipidemia, and cardiovascular disease in the clinic. Our previous study revealed that gallic acid, neochlorogenic acid, cryptochlorogenic acid, vitexin, and quercetin were active components of hawthorn. In this study, a simple, precise, and reliable liquid chromatography-mass spectrometry method was developed for the simultaneous quantification of five components in rat serums. The separation was achieved on the Hypersil GOLD C18 column, and the mobile phases consisted of 0.1% acetic acid water and methanol at a flow rate of 0.3 mL/min. The mass spectrometry data acquisition was performed on Q-Extractive-Orbitrap mass spectrometry with an electrospray ionization source in negative ion mode. The proposed liquid chromatography-mass spectrometry method was validated in terms of linearity, intra- and inter-precision, accuracy, recoveries, matrix effects, and stability. Then this newly proposed liquid chromatography-mass spectrometry method was successfully applied to a pharmacokinetic study on rats after oral administration of hawthorn aqueous extracts. This study provided relevant information on the pharmacokinetics of active components of hawthorn and explained the underlying mechanism of their bioactivity.


Assuntos
Crataegus , Medicamentos de Ervas Chinesas , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , Água
10.
Sensors (Basel) ; 23(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36616952

RESUMO

Flexible electrolyte-gated graphene field effect transistors (Eg-GFETs) are widely developed as sensors because of fast response, versatility and low-cost. However, their sensitivities and responding ranges are often altered by different gate voltages. These bias-voltage-induced uncertainties are an obstacle in the development of Eg-GFETs. To shield from this risk, a machine-learning-algorithm-based LgGFETs' data analyzing method is studied in this work by using Ca2+ detection as a proof-of-concept. For the as-prepared Eg-GFET-Ca2+ sensors, their transfer and output features are first measured. Then, eight regression models are trained with the use of different machine learning algorithms, including linear regression, support vector machine, decision tree and random forest, etc. Then, the optimized model is obtained with the random-forest-method-treated transfer curves. Finally, the proposed method is applied to determine Ca2+ concentration in a calibration-free way, and it is found that the relation between the estimated and real Ca2+ concentrations is close-to y = x. Accordingly, we think the proposed method may not only provide an accurate result but also simplify the traditional calibration step in using Eg-GFET sensors.


Assuntos
Grafite , Eletrólitos
11.
Small ; 17(43): e2100560, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33817963

RESUMO

Ruddlesden-Popper (RP) metal halide perovskites are considered as promising optoelectronic materials due to their good environmental stability and desirable optoelectronic properties. However, the phase composition and ordering in the deposited film, with a fixed ratio of large organic spacer cation in the precursor solution, are hard to be further tailored for specific optoelectronic applications. Herein, it is shown that even with a fixed spacer cation ratio, the phase composition and ordering can still be largely regulated by utilizing different crystallization kinetics of various cations with the inorganic octahedral lead halide. By using two different short cations to compete with the large spacer cation, the phase composition can be continuously tailored from thin multiple quantum wells (MQWs) dominated to 3D perovskite dominated. The phase ordering can be reversed from small n phases' prior to large n phases' prior near the substrate. Finally, with the same amount of large spacer cation protection, the perovskite can be tailored for both high-performance electroluminescence and photovoltaics with favorable energetic landscape for the corresponding desired first-order excitonic recombination and second-order free electron-hole recombination, respectively. This exploration substantially contributes to the understanding of precise phase engineering in RP perovskite and may provide a new insight into the design of multiple functional devices.

12.
J Nanobiotechnology ; 19(1): 214, 2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34275471

RESUMO

BACKGROUND: Cartilage injury and pathological degeneration are reported in millions of patients globally. Cartilages such as articular hyaline cartilage are characterized by poor self-regeneration ability due to lack of vascular tissue. Current treatment methods adopt foreign cartilage analogue implants or microfracture surgery to accelerate tissue repair and regeneration. These methods are invasive and are associated with the formation of fibrocartilage, which warrants further exploration of new cartilage repair materials. The present study aims to develop an injectable modified gelatin hydrogel. METHOD: The hydrogel effectively adsorbed proteoglycans secreted by chondrocytes adjacent to the cartilage tissue in situ, and rapidly formed suitable chondrocyte survival microenvironment modified by ε-poly-L-lysine (EPL). Besides, dynamic covalent bonds were introduced between glucose and phenylboronic acids (PBA). These bonds formed reversible covalent interactions between the cis-diol groups on polyols and the ionic boronate state of PBA. PBA-modified hydrogel induced significant stress relaxation, which improved chondrocyte viability and cartilage differentiation of stem cells. Further, we explored the ability of these hydrogels to promote chondrocyte viability and cartilage differentiation of stem cells through chemical and mechanical modifications. RESULTS: In vivo and in vitro results demonstrated that the hydrogels exhibited efficient biocompatibility. EPL and PBA modified GelMA hydrogel (Gel-EPL/B) showed stronger activity on chondrocytes compared to the GelMA control group. The Gel-EPL/B group induced the secretion of more extracellular matrix and improved the chondrogenic differentiation potential of stem cells. Finally, thus hydrogel promoted the tissue repair of cartilage defects. CONCLUSION: Modified hydrogel is effective in cartilage tissue repair.


Assuntos
Agrecanas/química , Agrecanas/farmacologia , Gelatina/química , Hidrogéis/química , Cicatrização/efeitos dos fármacos , Adsorção , Animais , Cartilagem Articular/patologia , Diferenciação Celular , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Matriz Extracelular , Humanos , Masculino , Camundongos , Polilisina , Polímeros , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual/métodos
13.
Biomed Chromatogr ; 35(6): e5076, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33476053

RESUMO

Dyspepsia, one of the most prevalent diseases of the digestive tract that impacts the quality of patient life, is mainly caused by gastrointestinal motility disorder. Hawthorn is a commonly used traditional Chinese medicine for treating dyspepsia, and has been proven to improve gastrointestinal motility. Herein, a rat model of gastrointestinal motility disorder was established by subcutaneous injection with atropine. The modeled rats were treated with four polar parts (T1-4 in descending polarity, corresponding to water, n-butanol, ethyl acetate and petroleum ether extracts, respectively) of hawthorn. Through metabolomics analysis, a total of 20 significantly metabolites were identified with significant changes in their abundance levels and these metabolites were related to many metabolic pathways such as amino acid metabolism and primary bile acid biosynthesis. The results showed that T3 had the best therapeutic effect of promoting gastrointestinal motility. Other parts showed no obvious therapeutic effect, demonstrating that the effective components of hawthorn may be compounds of medium polarity. T3 might achieve good therapeutic effects owing to the gastrointestinal motility promotion activity, and by rectifying the disturbed metabolic pathways in the gastrointestinal motility disorder model.


Assuntos
Crataegus/química , Gastroenteropatias/tratamento farmacológico , Motilidade Gastrointestinal/efeitos dos fármacos , Extratos Vegetais , Animais , Biomarcadores/sangue , Feminino , Masculino , Metabolômica , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley
14.
Small ; 16(18): e1907513, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32307895

RESUMO

Doped 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-MeOTAD), which acts as a hole-transporting layer (HTL), endows perovskite solar cells (PSCs) with excellent performance. However, the intrinsically hygroscopic nature of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) dopants also aggravates the moisture instability of PSCs. In this work, the origins of the moisture instability of spiro-MeOTAD HTLs are explored and strategies to enhance moisture resistance are proposed. After 780 h of aging in air, 52% of the initial power conversion efficiency (PCE) can be sustained by prolonging the mixing time of the precursor solution of spiro-MeOTAD to reduce accumulated LiTFSI. In contrast, only 7% of the initial PCE remains if the precursor solution is mixed briefly. By thermally annealing an HTL to evaporate residual tBP in spiro-MeOTAD, pinholes are completely eliminated and 65% of the initial PCE remains after the same aging time. In this study, the significance of the initial morphology of spiro-MeOTAD HTLs on device stability is analyzed and strategies based on physical morphology for controlling PSC moisture instability induced by HTL dopants are developed.

15.
Cell Commun Signal ; 18(1): 75, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32429933

RESUMO

An amendment to this paper has been published and can be accessed via the original article.

16.
Cell Commun Signal ; 18(1): 40, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32151266

RESUMO

BACKGROUND: Diabetic wounds are a disturbing and rapidly growing clinical problem. A novel peptide, parathyroid hormone related peptide (PTHrP-2), is assumed as multifunctional factor in angiogenesis, fibrogenesis and re-epithelization. This study aims to test PTHrP-2 efficiency and mechanism in wound healing. METHODS: Through repair phenomenon in vivo some problems were detected, and further research on their mechanisms was made. In vivo therapeutic effects of PTHrP-2 were determined by HE, Masson, microfil and immunohistochemical staining. In vitro direct effects of PTHrP-2 were determined by proliferation, migration, Vascular Endothelial Grown Factor and collagen I secretion of cells and Akt/ Erk1/2 pathway change. In vitro indirect effects of PTHrP-2 was study via exosomes. Exosomes from PTHrP-2 untreated and treated HUVECs and HFF-1 cells were insolated and identified. Exosomes were co-cultured with original cells, HUVECs or HFF-1 cells, and epithelial cells. Proliferation and migration and pathway change were observed. PTHrP-2-HUVEC-Exos were added into in vivo wound to testify its hub role in PTHrP-2 indirect effects in wound healing. RESULTS: In vivo, PTHrP-2 exerted multifunctional pro-angiogenesis, pro-firbogenesis and re-epithelization effects. In vitro, PTHrP-2 promoted proliferation and migration of endothelial and fibroblast cells, but had no effect on epithelial cells. Therefore, we tested PTHrP-2 indirect effects via exosomes. PTHrP-2 intensified intercellular communication between endothelial cells and fibroblasts and initiated endothelial-epithelial intercellular communication. PTHrP-2-HUVEC-Exos played a hub role in PTHrP-2 indirect effects in wound healing. CONCLUSION: These findings of this study indicated that PTHrP-2, a multifunctional factor, could promote wound healing via synergistic multicellular stimulating and exosomal activities.


Assuntos
Diabetes Mellitus Experimental , Proteína Relacionada ao Hormônio Paratireóideo , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Exossomos/metabolismo , Células HaCaT , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Proteína Relacionada ao Hormônio Paratireóideo/administração & dosagem , Proteína Relacionada ao Hormônio Paratireóideo/farmacologia , Ratos , Ratos Sprague-Dawley , Pele/patologia
17.
Small ; 15(25): e1900107, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31066210

RESUMO

Two-dimensional (2D) materials have attracted extensive research interest in academia due to their excellent electrochemical properties and broad application prospects. Among them, 2D transition metal carbides (Ti3 C2 Tx ) show semiconductor characteristics and are studied widely. However, there are few academic reports on the use of 2D MXene materials as memristors. In this work, reported is a memristor based on MXene Ti3 C2 Tx flakes. After electroforming, Al/Ti3 C2 Tx /Pt devices exhibit repeatable resistive switching (RS) behavior. More interestingly, the resistance of this device can be continuously modulated under the pulse sequence with 10 ns pulse width, and the pulse width of 10 ns is much lower than that in other reported work. Moreover, on the nanosecond scale, the transition from short-term plasticity to long-term plasticity is achieved. These two properties indicate that this device is favorable for ultrafast biological synapse applications and high-efficiency training of neural networks. Through the exploration of the microstructure, Ti vacancies and partial oxidation are proposed as the origins of the physical mechanism of RS behavior. This work reveals that 2D MXene Ti3 C2 Tx flakes have excellent potential for use in memristor devices, which may open the door for more functions and applications.

18.
Small ; 15(24): e1901423, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31045332

RESUMO

Memristors with nonvolatile memory characteristics have been expected to open a new era for neuromorphic computing and digital logic. However, existing memristor devices based on oxygen vacancy or metal-ion conductive filament mechanisms generally have large operating currents, which are difficult to meet low-power consumption requirements. Therefore, it is very necessary to develop new materials to realize memristor devices that are different from the mechanisms of oxygen vacancy or metal-ion conductive filaments to realize low-power operation. Herein, high-performance and low-power consumption memristors based on 2D WS2 with 2H phase are demonstrated, which show fast ON (OFF) switching times of 13 ns (14 ns), low program current of 1 µA in the ON state, and SET (RESET) energy reaching the level of femtojoules. Moreover, the memristor can mimic basic biological synaptic functions. Importantly, it is proposed that the generation of sulfur and tungsten vacancies and electron hopping between vacancies are dominantly responsible for the resistance switching performance. Density functional theory calculations show that the defect states formed by sulfur and tungsten vacancies are at deep levels, which prevent charge leakage and facilitate the realization of low-power consumption for neuromorphic computing application.

19.
Macromol Rapid Commun ; 40(4): e1800815, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30600569

RESUMO

This article introduces a simple two-stage method to synthesize and program a photomechanical elastomer (PME) for light-driven artificial muscle-like actuations in soft robotics. First, photochromic azobenzene molecules are covalently attached to a polyurethane backbone via a two-part step-growth polymerization. Next, mechanical alignment is applied to induce anisotropic deformations in the PME-actuating films. Cross-linked through dynamic hydrogen bonds, the PMEs also possess autonomic self-healing properties without external energy input. This self-healing allows for a single alignment step of the PME film and subsequent "cut and paste" assembly for multi-axis actuation of a self-folded soft-robotic gripper from a single degree of freedom optical input.


Assuntos
Elastômeros/síntese química , Compostos Azo/química , Elastômeros/química , Ligação de Hidrogênio , Estrutura Molecular , Processos Fotoquímicos , Estresse Mecânico
20.
Opt Lett ; 41(3): 555-8, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26907422

RESUMO

The synthesized perovskites are randomly distributed and their optical properties are fixed after synthesis. Here we demonstrate the tailoring of lasing properties of perovskite microwire via micromanipulation. One microwire has been lifted by a tungsten probe and repositioned on a nearby perovskite microplate with one end suspended in air. Consequently, the conventional Fabry-Perot lasers are completely suppressed and a single laser peak has been observed. The numerical calculations reveal that the single-mode laser is formed by the whispering-gallery mode in the transverse plane of microwire. Our research provides a simple way to tailor the properties of microwire postsynthesis.

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