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1.
Sensors (Basel) ; 24(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38475029

RESUMO

In recent years, there has been a notable rise in the number of patients afflicted with laryngeal diseases, including cancer, trauma, and other ailments leading to voice loss. Currently, the market is witnessing a pressing demand for medical and healthcare products designed to assist individuals with voice defects, prompting the invention of the artificial throat (AT). This user-friendly device eliminates the need for complex procedures like phonation reconstruction surgery. Therefore, in this review, we will initially give a careful introduction to the intelligent AT, which can act not only as a sound sensor but also as a thin-film sound emitter. Then, the sensing principle to detect sound will be discussed carefully, including capacitive, piezoelectric, electromagnetic, and piezoresistive components employed in the realm of sound sensing. Following this, the development of thermoacoustic theory and different materials made of sound emitters will also be analyzed. After that, various algorithms utilized by the intelligent AT for speech pattern recognition will be reviewed, including some classical algorithms and neural network algorithms. Finally, the outlook, challenge, and conclusion of the intelligent AT will be stated. The intelligent AT presents clear advantages for patients with voice impairments, demonstrating significant social values.


Assuntos
Faringe , Voz , Humanos , Som , Algoritmos , Redes Neurais de Computação
2.
Sensors (Basel) ; 24(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38400251

RESUMO

A surface-enhanced Raman scattering (SERS) method for measuring nitrate nitrogen in aquaculture water was developed using a substrate of ß-cyclodextrin-modified gold nanoparticles (SH-ß-CD@AuNPs). Addressing the issues of low sensitivity, narrow linear range, and relatively poor selectivity of single metal nanoparticles in the SERS detection of nitrate nitrogen, we combined metal nanoparticles with cyclodextrin supramolecular compounds to prepare a AuNPs substrate enveloped by cyclodextrin, which exhibits ultra-high selectivity and Raman activity. Subsequently, vanadium(III) chloride was used to convert nitrate ions into nitrite ions. The adsorption mechanism between the reaction product benzotriazole (BTAH) of o-phenylenediamine (OPD) and nitrite ions on the SH-ß-CD@AuNPs substrate was studied through SERS, achieving the simultaneous detection of nitrate nitrogen and nitrite nitrogen. The experimental results show that BTAH exhibits distinct SERS characteristic peaks at 1168, 1240, 1375, and 1600 cm-1, with the lowest detection limits of 3.33 × 10-2, 5.84 × 10-2, 2.40 × 10-2, and 1.05 × 10-2 µmol/L, respectively, and a linear range of 0.1-30.0 µmol/L. The proposed method provides an effective tool for the selective and accurate online detection of nitrite and nitrate nitrogen in aquaculture water.

3.
Nano Lett ; 24(4): 1231-1237, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38251914

RESUMO

Ferroelectricity, especially the Si-compatible type recently observed in hafnia-based materials, is technologically useful for modern memory and logic applications, but it is challenging to differentiate intrinsic ferroelectric polarization from the polar phase and oxygen vacancy. Here, we report electrically controllable ferroelectricity in a Hf0.5Zr0.5O2-based heterostructure with Sr-doped LaMnO3, a mixed ionic-electronic conductor, as an electrode. Electrically reversible extraction and insertion of an oxygen vacancy into Hf0.5Zr0.5O2 are macroscopically characterized and atomically imaged in situ. Utilizing this reversible process, we achieved multilevel polarization states modulated by the electric field. Our study demonstrates the usefulness of the mixed conductor to repair, create, manipulate, and utilize advanced ferroelectric functionality. Furthermore, the programmed ferroelectric heterostructures with Si-compatible doped hafnia are desirable for the development of future ferroelectric electronics.

4.
Adv Sci (Weinh) ; 10(34): e2303734, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37814361

RESUMO

Two-dimensional material-based field-effect transistors (2DM-FETs) are playing a revolutionary role in electronic devices. However, before electronic design automation (EDA) for 2DM-FETs can be achieved, it remains necessary to determine how to incorporate contact transports into model. Reported methods compromise between physical intelligibility and model compactness due to the heterojunction nature. To address this, quasi-Fermi-level phase space theory (QFLPS) is generalized to incorporate contact transports using the Landauer formula. It turns out that the Landauer-QFLPS model effectively overcomes the issue of concern. The proposed new formula can describe 2DM-FETs with Schottky or Ohmic contacts with superior accuracy and efficiency over previous methods, especially when describing non-monotonic drain conductance characteristics. A three-bit threshold inverter quantizer (TIQ) circuit is fabricated using ambipolar black phosphorus and it is demonstrated that the model accurately predicts circuit performance. The model could be very effective and valuable in the development of 2DM-FET-based integrated circuits.

5.
Materials (Basel) ; 16(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37687645

RESUMO

With the development of medical technology and increasing demands of healthcare monitoring, wearable temperature sensors have gained widespread attention because of their portability, flexibility, and capability of conducting real-time and continuous signal detection. To achieve excellent thermal sensitivity, high linearity, and a fast response time, the materials of sensors should be chosen carefully. Thus, reduced graphene oxide (rGO) has become one of the most popular materials for temperature sensors due to its exceptional thermal conductivity and sensitive resistance changes in response to different temperatures. Moreover, by using the corresponding preparation methods, rGO can be easily combined with various substrates, which has led to it being extensively applied in the wearable field. This paper reviews the state-of-the-art advances in wearable temperature sensors based on rGO films and summarizes their sensing mechanisms, structure designs, functional material additions, manufacturing processes, and performances. Finally, the possible challenges and prospects of rGO-based wearable temperature sensors are briefly discussed.

6.
Polymers (Basel) ; 15(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37376345

RESUMO

Spatial distribution perception has become an important trend for flexible pressure sensors, which endows wearable health devices, bionic robots, and human-machine interactive interfaces (HMI) with more precise tactile perception capabilities. Flexible pressure sensor arrays can monitor and extract abundant health information to assist in medical detection and diagnosis. Bionic robots and HMI with higher tactile perception abilities will maximize the freedom of human hands. Flexible arrays based on piezoresistive mechanisms have been extensively researched due to the high performance of pressure-sensing properties and simple readout principles. This review summarizes multiple considerations in the design of flexible piezoresistive arrays and recent advances in their development. First, frequently used piezoresistive materials and microstructures are introduced in which various strategies to improve sensor performance are presented. Second, pressure sensor arrays with spatial distribution perception capability are discussed emphatically. Crosstalk is a particular concern for sensor arrays, where mechanical and electrical sources of crosstalk issues and the corresponding solutions are highlighted. Third, several processing methods are also introduced, classified as printing, field-assisted and laser-assisted fabrication. Next, the representative application works of flexible piezoresistive arrays are provided, including human-interactive systems, healthcare devices, and some other scenarios. Finally, outlooks on the development of piezoresistive arrays are given.

7.
Materials (Basel) ; 16(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37297066

RESUMO

As the focus on physical health increases, the market demand for flexible wearable sensors increases. Textiles combined with sensitive materials and electronic circuits can form flexible, breathable high-performance sensors for physiological-signal monitoring. Carbon-based materials such as graphene, carbon nanotubes (CNTs), and carbon black (CB) have been widely utilized in the development of flexible wearable sensors due to their high electrical conductivity, low toxicity, low mass density, and easy functionalization. This review provides an overview of recent advancements in carbon-based flexible textile sensors, highlighting the development, properties, and applications of graphene, CNTs, and CB for flexible textile sensors. The physiological signals that can be monitored by carbon-based textile sensors include electrocardiogram (ECG), human body movement, pulse and respiration, body temperature, and tactile perception. We categorize and describe carbon-based textile sensors based on the physiological signals they monitor. Finally, we discuss the current challenges associated with carbon-based textile sensors and explore the future direction of textile sensors for monitoring physiological signals.

8.
Materials (Basel) ; 16(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36984013

RESUMO

Continuous blood pressure (BP) monitoring is of great significance for the real-time monitoring and early prevention of cardiovascular diseases. Recently, wearable BP monitoring devices have made great progress in the development of daily BP monitoring because they adapt to long-term and high-comfort wear requirements. However, the research and development of wearable continuous BP monitoring devices still face great challenges such as obvious motion noise and slow dynamic response speeds. The pulse wave transit time method which is combined with photoplethysmography (PPG) waves and electrocardiogram (ECG) waves for continuous BP monitoring has received wide attention due to its advantages in terms of excellent dynamic response characteristics and high accuracy. Here, we review the recent state-of-art wearable continuous BP monitoring devices and related technology based on the pulse wave transit time; their measuring principles, design methods, preparation processes, and properties are analyzed in detail. In addition, the potential development directions and challenges of wearable continuous BP monitoring devices based on the pulse wave transit time method are discussed.

9.
Nanomicro Lett ; 14(1): 161, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35943631

RESUMO

With the aging of society and the increase in people's concern for personal health, long-term physiological signal monitoring in daily life is in demand. In recent years, electronic skin (e-skin) for daily health monitoring applications has achieved rapid development due to its advantages in high-quality physiological signals monitoring and suitability for system integrations. Among them, the breathable e-skin has developed rapidly in recent years because it adapts to the long-term and high-comfort wear requirements of monitoring physiological signals in daily life. In this review, the recent achievements of breathable e-skins for daily physiological monitoring are systematically introduced and discussed. By dividing them into breathable e-skin electrodes, breathable e-skin sensors, and breathable e-skin systems, we sort out their design ideas, manufacturing processes, performances, and applications and show their advantages in long-term physiological signal monitoring in daily life. In addition, the development directions and challenges of the breathable e-skin are discussed and prospected.

10.
J Cosmet Dermatol ; 21(12): 6742-6753, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36038248

RESUMO

OBJECTIVE: This study aimed to analyze the clinical results and influencing factors of the fractional microneedle radiofrequency (FMR) treatment for enlarged facial pores on different facial sites. METHODS: The clinical data of patients with enlarged facial pores who underwent FMR treatment from January 2019 to December 2020 were collected. The efficacy and complications of FMR for enlarged pores in different facial areas were retrospectively analyzed. Univariate and multivariate logistic regression analyses were used to explore the clinical factors related to the efficacy of FMR after the first treatment session. RESULTS: Totally, 75 patients with enlarged facial pores were included (full-face FMR for 45, nasal FMR for 58, frontal FMR for 45, and cheek FMR for 72 patients). All patients received more than one treatment session, two patients received five treatment sessions, and the mean number of FMR session was 1.7. The moderate to excellent improvement rates in patients with nasal, frontal and cheek enlarged pores after the first session were 13.8%, 8.9%, and 11.1%, respectively. The improvement rate rose with the increasing number of treatment sessions. Multivariate logistic regression analysis revealed that long pulse-width (300 ms) was positively associated with clinical efficacy after the first session (OR = 22.4, 95% CI [2.0-250.4], p = 0.012), compared with the short pulse-width group (100-200 ms). The main adverse effects after FMR were transient pain, erythema, and edema. A minority of patients developed acneiform eruption. CONCLUSION: This study confirms that FMR is safe and effective in improving enlarged facial pores. The pulse width is associated with the improvement of nasal enlarged pores.


Assuntos
Acne Vulgar , Terapia por Radiofrequência , Humanos , Acne Vulgar/complicações , Estudos Retrospectivos , Resultado do Tratamento , Eritema/etiologia
11.
J Cosmet Dermatol ; 21(5): 1989-1997, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35181995

RESUMO

OBJECTIVE: This study was performed to analyze the efficacy, adverse reactions of fractional CO2  laser for atrophic acne scars, and related clinical factors. METHODS: The clinical data of 121 patients with atrophic acne scars treated with ultra-pulsed fractional CO2  laser in the Cosmetic Dermatology from August 2014 to March 2020 were retrospectively analyzed. The efficacy and adverse reactions of atrophic acne scar after fractional CO2  laser therapy were statistically analyzed. The clinical factors related to efficacy and adverse reactions after the first therapy session were analyzed by multivariate logistic regression. RESULTS: A total of 121 patients received 206 sessions of fractional CO2  laser therapy, with an average of 1.7 sessions. Moderate to excellent improvement rate reached 50.4% after the first session. Multivariate logistic regression analysis indicated that rolling scars responded better to fractional CO2  laser treatment than icepick scars (OR = 7.3, 95% CI [1.2, 43.4], p = 0.029), and scar improvement was more significant in the high-energy laser group than in the low-energy laser group (OR = 10.9, 95% CI [1.1, 106.8], p = 0.041). The main adverse reactions after fractional laser surgery were pigmentation, skin sensitivity, persistent erythema, and acneiform eruption. Multivariate logistic analysis revealed that the longer the scar duration, the higher incidence of postoperative adverse reactions (OR = 1.3, 95% CI [1.1, 1.5], p = 0.008). Compared with icepick scars, rolling scars (OR = 10.4, 95% CI [2.3, 47.7], p = 0.003) and boxcar scars (OR = 12.0, 95% CI [3.3, 44.0], p < 0.001) had higher risk of developing adverse reactions. The incidence of postoperative adverse reactions was also higher in the combined mode group (DeepFX mode + ActiveFX mode) than in the single-mode group (OR = 7.8, 95% CI [2.4, 25.5], p < 0.001). CONCLUSION: Fractional CO2 laser was effective in the treatment of atrophic acne scars, without serious adverse reactions. Scar type and laser energy were independent clinical factors affecting its efficacy. Scar course, scar type, and fractional laser mode were independent clinical factors affecting its adverse reactions.


Assuntos
Acne Vulgar , Terapia a Laser , Lasers de Gás , Acne Vulgar/complicações , Atrofia/complicações , Atrofia/cirurgia , Dióxido de Carbono , Cicatriz/etiologia , Cicatriz/patologia , Cicatriz/cirurgia , Humanos , Terapia a Laser/efeitos adversos , Lasers de Gás/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
12.
Adv Sci (Weinh) ; 7(19): 2001266, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33042746

RESUMO

Ferroelectric memories with ultralow-power-consumption are attracting a great deal of interest with the ever-increasing demand for information storage in wearable electronics. However, sufficient scalability, semiconducting compatibility, and robust flexibility of the ferroelectric memories remain great challenges, e.g., owing to Pb-containing materials, oxide electrode, and limited thermal stability. Here, high-performance flexible nonvolatile memories based on ferroelectric Hf0.5Zr0.5O2 (HZO) via quasi-van der Waals heteroepitaxy are reported. The flexible ferroelectric HZO exhibits not only high remanent polarization up to 32.6 µC cm-2 without a wake-up effect during cycling, but also remarkably robust mechanical properties, degradation-free retention, and endurance performance under a series of bent deformations and cycling tests. Intriguingly, using HZO as a gate, flexible ferroelectric thin-film transistors with a low operating voltage of ±3 V, high on/off ratio of 6.5 × 105, and a small subthreshold slope of about 100 mV dec-1, which outperform reported flexible ferroelectric transistors, are demonstrated. The results make ferroelectric HZO a promising candidate for the next-generation of wearable, low-power, and nonvolatile memories with manufacturability and scalability.

13.
Medicine (Baltimore) ; 98(48): e17948, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31770202

RESUMO

BACKGROUND: Laser systems are a common treatment choice for onychomycosis. They exert their effects on inhibiting the growth of the fungus by selective photothermolysis but efficacy is dependent on the specific type of apparatus used. To systematically review the available published literature on the curative effects and safety of laser treatment for onychomycosis. METHODS: Databases including PubMed, web of science, China National Knowledge Internet (CNKI), WanFang Database and VIP were searched systematically to identify relevant articles published up to July 2018. Potentially relevant articles were sourced, assessed against eligibility criteria by 2 researchers independently and data were extracted from included studies. A meta-analysis was performed using R software. RESULTS: Thirty-five articles involving 1723 patients and 4278 infected nails were included. Meta-analysis of data extracted from these studies revealed that: the overall mycological cure rate was 63.0% (95%CI 0.53-0.73); the mycological cure rate associated with the 1064-nm Nd: YAG laser was 63.0% (95%CI 0.51-0.74); and that of CO2 lasers was 74.0% (95%CI 0.37-0.98). The published data indicate that laser treatment is relatively safe, but can cause tolerable pain and occasionally lead to bleeding after treatment. CONCLUSION: Laser treatment of onychomycosis is effective and safe. The cumulative cure rate of laser treatment was significantly higher for CO2 lasers than other types of laser. Laser practitioners should be made aware of potential adverse effects such as pain and bleeding.


Assuntos
Lasers de Gás/uso terapêutico , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Onicomicose/radioterapia , Humanos , Unhas/efeitos da radiação , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
14.
Medicine (Baltimore) ; 98(32): e16362, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393345

RESUMO

RATIONALE: Atopic dermatitis (AD) is a chronic recurrent dermatitis with profound itching, which could be the first manifestation of acute myeloid leukemia (AML). PATIENT CONCERNS: A 53-year-old Chinese man suffered a 6-month history of systemic symmetrical dermatitis, accompanied with profound itching. The patient was diagnosed as "eczema" in several hospitals, and the effects of antihistamine and topical steroid creams were poor. Nocturnal sleep was seriously affected by aggravating pruritus. Laboratorial examination was compatible with AML-M4. DIAGNOSES: AML-M4 with AD as first manifestation. INTERVENTIONS: IA regimen (ayninen and cytarabine) were used in induction chemotherapy. However, the patient did not achieve complete remission, and although his rash had improved, he still experienced severely general body itching. On the seventh day of chemotherapy, the patient entered the period of granulocyte deficiency with infection. OUTCOMES: The patient died due to septic shock after chemotherapy. LESSONS: The case strengthens the awareness of AML with AD as first manifestation and raises oncological vigilance in patients with AD refractory.


Assuntos
Dermatite Atópica/etiologia , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Dermatite Atópica/tratamento farmacológico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/fisiopatologia , Masculino , Pessoa de Meia-Idade
15.
J Cosmet Dermatol ; 18(1): 10-15, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30548742

RESUMO

Botulinum Toxin Type A is a potent neurotoxin that is produced by a gram-positive bacteria clostridium botulinum. Its utilization in the treatment of various medical condition has expanded over the years in both medical and esthetic uses. It is being preferred by most physicians due to its efficacy and lack of side effects. It can be used as monotherapy or combined therapy. The aim of this review study was to show the role and mechanism of action of Botulinum toxin type A in the treatment and prevention of hypertrophic scars and keloids. The clear mechanisms underlying hypertrophic scars and keloids are still not clearly understood; however, the mechanism of action of Botulinum toxin type A has been shown to include action on wound tension, action on collagen, and action on fibroblasts. Different randomized controlled trials, double-blind, and placebo-controlled studies have been conducted to investigate its use in treatment and prevention of hypertrophic scars and keloids, and it still is one of the active areas of research in Dermatology and related fields. Method: In March 2018, we performed a literature search in PubMed for clinical studies, clinical trials, case reports, controlled trials, randomized controlled trials, and systemic reviews. The search terms we used were "BOTULINUM TOXIN" AND "HYPERTROPHIC SCARS" OR "KELOIDS" (from 1980). The search resulted in 1000 articles, out of these 35 articles met our inclusion exclusion criteria. Our inclusion criteria included relevant original articles relevant, critical systemic reviews, and crucial referenced articles, exclusion criteria included duplicates and articles not published in English language. We have reviewed these papers to show the role and mechanism of action of Botulinum toxin type A in the treatment and prevention of hypertrophic scars and keloids.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Cicatriz Hipertrófica/prevenção & controle , Queloide/prevenção & controle , Neurotoxinas/uso terapêutico , Cicatrização/efeitos dos fármacos , Toxinas Botulínicas Tipo A/farmacologia , Ciclo Celular/efeitos dos fármacos , Cicatriz Hipertrófica/tratamento farmacológico , Fibroblastos/fisiologia , Expressão Gênica/efeitos dos fármacos , Humanos , Queloide/tratamento farmacológico , Neurotoxinas/farmacologia
16.
RSC Adv ; 8(55): 31331-31336, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-35548222

RESUMO

Ultra-wideband (UWB), a radio transmission technology with wide bandwidth exceeding the minimum of 500 MHz or at least 20% of the center frequency, is a revolutionary approach for short-range high-bandwidth wireless communication. In this study, carbon nanotube (CNT) UWB antennas by direct laser-patterning technology have been successfully designed, fabricated and characterized. In contrast with traditional fabrication methods, the direct laser-patterning technology offers an exceptional potential for custom-designed, high-complexity and accuracy device fabrication. The "engraving" process on CNTs exposed to laser can be attributed to the bond breaking of C-C, evaporation of carbon atoms, and oxidation of CNTs by the oxygen molecules. Numerical analysis and experimental studies provide characteristics of CNT slot antennas with a wide impedance bandwidth (from 3.4 GHz to 14 GHz for S11 ≤ -10 dB), high average radiation efficiency (76%) and fractional bandwidth (121%) with small size of 30 × 30 mm2. The results indicate the advantages of laser-patterned UWB antennas based on carbon nanotubes, which paves the way for industrial applications, particularly in the world of consumer electronics.

17.
RSC Adv ; 8(65): 37534-37539, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35557812

RESUMO

The transition from the current 4th generation mobile networks (4G) to the next generation, known as 5th generation mobile networks (5G), is expected to occur within the next decade. To provide greater network speed, capacity and better coverage, the wireless broadband technologies need to update traditional antennas for high frequency and millimeter wavelengths. In this study, meander line dipole antennas produced by direct ink-injecting technology have been successfully designed, fabricated and characterized, where the ink-injecting technology may open new routes to the fabrication of wireless antenna applications. An accurate electromagnetic numerical analysis model for the proposed meander line antenna is also developed. The designed dual-band antenna based on graphene flakes and Ag nanowires can operate from 1.2 GHz up to the 1.5 GHz band and from 3.2 GHz up to the 3.8 GHz band with |S 11| > 10 dB for wireless communications applications. Different mixtures by mass ratio of aqueous dispersions of CNTs and Ag nanowires (1 : 1, 5 : 1, 10 : 1, 20 : 1) are also prepared to investigate the influence of the network structure on the performance of the meander line antennas.

18.
Mol Med Rep ; 15(4): 1816-1822, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28259957

RESUMO

Treating skin and soft tissue infections of severe limb traumas can be challenging. Crucial concerns focus on inhibiting biofilm formation by antibiotic­resistant bacteria, and preventing scar formation by fibroblastic hyperproliferation. The local use of toluidine blue O (TBO)­mediated photodynamic therapy (PDT) may be a promising strategy for treating such lesions. The present study used Staphylococcus epidermidis (strain ATCC 35984) to assess the effects of TBO­PDT on bacterial adherence and biofilm formation, using confocal laser scanning microscopy (CLSM), tissue culture plating (TCP) and scanning electron microscopy (SEM). Primary human fibroblast cells were used to evaluate the cytotoxicity of TBO­PDT using the 3­(4,5­dimethylthiazol­2­yl)­2,5­diphenyltetrazolium bromide (MTT) assay and CLSM. Six different treatment groups were investigated: Medium only [tryptone soy broth (TSB) or Dulbecco's modified Eagle's medium (DMEM)]; red light control (light dose, 30 J/cm2); TBO group (50 mM TBO); TBO­PDT1 (TBO irradiated with 10 J/cm2); TBO­PDT2 (TBO irradiated with 20 J/cm2); and TBO­PDT3 (TBO irradiated with 30 J/cm2). The results of the S. epidermidis adhesion assay indicated that the TSB, light and TBO groups exhibited significant bacterial adherence, compared with the TBO­PDT groups. Analysis of biofilm formation revealed significant light dose­dependent differences between the TBO­PDT groups and the TSB, light, and TBO groups. Furthermore, SEM indicated fewer colony masses in the TBO­PDT groups compared with the control groups. The MTT assay for fibroblastic cell toxicity demonstrated ~1.1, 4.6, 14.5, 29.7 and 43.4% reduction in optical density for the light, TBO, TBO­PDT1, TBO­PDT2 and TBO­PDT3 groups, respectively, compared with the DMEM control group. There was no difference in toxicity between the light and control groups, however, there were significant differences among the TBO­PDT groups. Finally, alterations in fibroblast morphology and cell spreading were revealed by CLSM, following TBO­PDT treatment. TBO­PDT inhibited bacterial adhesion and biofilm formation, and exhibited significant cytotoxic effects on human fibroblasts. These results indicate that the local use of TBO­PDT in limb lesions may be a useful treatment method for inhibiting bacterial biofilm formation and fibroblastic hyperproliferation, which may prevent infectious hypertrophic scar formation.


Assuntos
Fibroblastos/efeitos dos fármacos , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Staphylococcus epidermidis/efeitos dos fármacos , Cloreto de Tolônio/farmacologia , Animais , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Humanos , Camundongos
19.
Sci Rep ; 5: 18269, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26658213

RESUMO

Magnetization switching between parallel and antiparallel alignments of two magnetic layers in magnetic tunnel junctions (MTJs) is conventionally controlled either by an external magnetic field or by an electric current. Here, we report that the manipulation of magnetization switching and tunnel magnetoresistance (TMR) in perpendicularly magnetized CoFeB/MgO/CoFeB MTJs can be achieved by both temperature and voltage. At a certain range of temperature, coercivity crossover between top and bottom magnetic layers is observed in which the TMR ratio of the MTJs is almost unmeasurable. Furthermore, the temperature range can be tuned reversibly by an electric voltage. Magnetization switching driven by the voltage reveals an unconventional phenomenon such that the voltage driven coercivity changes with temperature are quite different for top and bottom CoFeB layers. A model based on thermally-assisted domain nucleation and propagation is developed to explain the frequency and temperature dependence of coercivity. The present results of controlling the magnetization switching by temperature and voltage may provide an alternative route for novel applications of MTJs based spintronic devices.

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