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1.
Nanoscale ; 14(42): 15607-15616, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36268821

RESUMO

The solution processability of organic semiconductors and conjugated polymers along with the advent of nanomaterials as conducting inks have revolutionized next-generation flexible consumer electronics. Another equally important class of nanomaterials, self-assembled peptides, heralded as next-generation materials for bioelectronics, have a lot of potential in printed technology. In this minireview, we address the self-assembly process in dipeptides, their application in electronics, and recent progress in three-dimensional printing. The prospect of a generalizable path for nanopatterning self-assembled peptides using ice lithography and its challenges are further discussed.


Assuntos
Nanoestruturas , Nanoestruturas/química , Eletrônica/métodos , Semicondutores , Peptídeos , Impressão Tridimensional
2.
Nat Nanotechnol ; 16(6): 688-697, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33782589

RESUMO

We developed a bioelectronic communication system that is enabled by a redox signal transduction modality to exchange information between a living cell-embedded bioelectronics interface and an engineered microbial network. A naturally communicating three-member microbial network is 'plugged into' an external electronic system that interrogates and controls biological function in real time. First, electrode-generated redox molecules are programmed to activate gene expression in an engineered population of electrode-attached bacterial cells, effectively creating a living transducer electrode. These cells interpret and translate electronic signals and then transmit this information biologically by producing quorum sensing molecules that are, in turn, interpreted by a planktonic coculture. The propagated molecular communication drives expression and secretion of a therapeutic peptide from one strain and simultaneously enables direct electronic feedback from the second strain, thus enabling real-time electronic verification of biological signal propagation. Overall, we show how this multifunctional bioelectronic platform, termed a BioLAN, reliably facilitates on-demand bioelectronic communication and concurrently performs programmed tasks.


Assuntos
Eletrônica/métodos , Escherichia coli/metabolismo , Microrganismos Geneticamente Modificados/metabolismo , 4-Butirolactona/análogos & derivados , 4-Butirolactona/metabolismo , Células Imobilizadas/química , Eletrodos , Desenho de Equipamento , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Regulação Bacteriana da Expressão Gênica , Ouro/química , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Peróxido de Hidrogênio/metabolismo , Microbiota , Microrganismos Geneticamente Modificados/genética , Oxirredução , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , beta-Galactosidase/metabolismo
3.
Sci Rep ; 10(1): 16407, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009470

RESUMO

To develop an electronic navigation system to increase reliability and comparability in the ultrasound screening of developmental dysplasia of the hip (DDH). The impact of the navigation system on transducer positioning and on sonographic measurements according to Graf was analyzed. Twenty hips in newborns were examined sonographically using a new navigation system capable of detecting the transducer and pelvis position in order to calculate the relative tilt in the frontal, axial, and sagittal-plane. In each newborn an ultrasound image was obtained conventionally according to Graf and a second image using the sonographic navigation system. Relative roll and pitch angles and sonographic measurements were analyzed using paired T-tests and Levene-tests. Relative tilt angles in the conventional group ranged from - 8.9° to 14.3° (frontal-plane) and - 23.8° to 14.2° (axial-plane). In the navigation-assisted group ranges from - 3.0° to 3.5° and - 2.8° to 4.5° were observed. Variances were significantly lower in the navigation-assisted group (p < 0.001 and p = 0.004 respectively). The navigation system allowed for a significant reduction of relative tilt angles between the transducer and the newborn pelvis, thus supporting an optimal transducer positioning. This is a promising approach to improve reproducibility and reliability in the ultrasound screening for DDH.


Assuntos
Displasia do Desenvolvimento do Quadril/diagnóstico , Eletrônica/métodos , Luxação Congênita de Quadril/diagnóstico , Ultrassonografia/métodos , Feminino , Quadril/patologia , Humanos , Recém-Nascido , Masculino , Triagem Neonatal/métodos , Reprodutibilidade dos Testes , Transdutores
4.
Carbohydr Polym ; 246: 116613, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32747253

RESUMO

The article summarizes the roles of polysaccharides in the biology of fungi and their relationship in the development of new technologies. The comparative approach between the evolution of fungi and the chemistry of glycobiology elucidated relevant aspects about the role of polysaccharides in fungi. Also, based on the knowledge of fungal glycobiology, it was possible to address the development of new technologies, such as the production of new anti-tumor drugs, vaccines, biomaterials, and applications in the field of robotics. We conclude that polysaccharides activate pathways of apoptosis, secretion of pro-inflammatory substances, and macrophage, inducing anticancer activity. Also, the activation of the immune system, which opens the way for the production of vaccines. The development of biomaterials and parts for robotics is a promising and little-explored field. Finally, the article is multidisciplinary, with a different and integrated approach to the role of nature in the sustainable development of new technologies.


Assuntos
Antineoplásicos/química , Biotecnologia/métodos , Polissacarídeos Fúngicos/química , Fungos/química , Fatores Imunológicos/química , Antineoplásicos/classificação , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Materiais Biocompatíveis/isolamento & purificação , Materiais Biocompatíveis/farmacologia , Eletrônica/métodos , Polissacarídeos Fúngicos/classificação , Polissacarídeos Fúngicos/isolamento & purificação , Polissacarídeos Fúngicos/farmacologia , Fungos/metabolismo , Glicômica/métodos , Humanos , Fatores Imunológicos/classificação , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Reologia , Robótica/métodos , Transdução de Sinais , Vacinas/administração & dosagem , Vacinas/síntese química
5.
Curr Oncol ; 27(2): e156-e162, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32489264

RESUMO

Introduction: Improving health-related quality of life (hrqol) is a key goal of systemic therapy in advanced lung cancer, although routine assessment remains challenging. We analyzed the impact of a real-time electronic hrqol tool, the electronic Lung Cancer Symptom Scale (elcss-ql), on palliative care (pc) referral rates, patterns of chemotherapy treatment, and use of other supportive interventions in patients with advanced non-small-cell lung cancer (nsclc) receiving first-line chemotherapy. Methods: Patients with advanced nsclc starting first-line chemotherapy were randomized to their oncologist receiving or not receiving their elcss-ql data before each clinic visit. Patients completed the elcss-ql at baseline, before each chemotherapy cycle, and at subsequent follow-up visits until disease progression. Prospective data about the pc referral rate, hrqol, and use of other supportive interventions were collected. Results: For the 95 patients with advanced nsclc who participated, oncologists received real-time elcss-ql data for 44 (elcss-ql arm) and standard clinical assessment alone for 51 (standard arm). The primary endpoint, the pc referral rate, was numerically higher, but statistically similar, for patients in the elcss-ql and standard arms. The hrqol scores over time were not significantly different between the two study arms. Conclusions: The elcss-ql is feasible as a tool for use in routine clinical practice, although no statistically significant effect of its use was demonstrated in our study. Improving access to supportive care through the collection of patient-reported outcomes and hrqol should be an important component of care for patients with advanced lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/psicologia , Eletrônica/métodos , Neoplasias Pulmonares/psicologia , Cuidados Paliativos/métodos , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Sci Rep ; 10(1): 5612, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32221375

RESUMO

Most smokers who use electronic cigarettes (e-cigarettes) to stop smoking simultaneously use conventional cigarettes (dual users). We aimed to compare the prevalence of cardiovascular risk factors among dual users, cigarette-only smokers, and never smokers in Korean men. We used data acquired from Korean National Health and Nutrition Examination Survey (2013-2017) pertaining to 7,505 male participants aged 19 years or older. About 85% of e-cigarette users were dual users. Dual users had greater nicotine dependence and higher urinary cotinine levels than cigarette-only smokers. Dual users had more psychosocial and behavioural risk factors, including perceived high stress, depressive mood, high daily intake of energy, and obesity, than never smokers and cigarette-only smokers. The prevalence of metabolic syndrome (MetS) was higher among dual users, and their multivariate-adjusted prevalence odds ratio for MetS was 2.79 (P < 0.001) compared with never smokers and 1.57 (P = 0.038) compared with cigarette-only smokers. Given that most e-cigarette users are dual users and dual users are more vulnerable to cardiovascular risk factors than cigarette-only smokers and never smokers, more active treatment for smoking cessation and intensive lifestyle interventions for dual users should be considered with priority.


Assuntos
Doenças Cardiovasculares/etiologia , Fumar Cigarros/efeitos adversos , Produtos do Tabaco/efeitos adversos , Adulto , Sistemas Eletrônicos de Liberação de Nicotina , Eletrônica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , República da Coreia , Fatores de Risco , Fumantes , Inquéritos e Questionários , Tabagismo/etiologia , Adulto Jovem
7.
Sensors (Basel) ; 20(5)2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32121478

RESUMO

Wireless body area networks (WBANs) have become a new paradigm for electronic healthcare applications; for instance, they are used to efficiently monitor patients in real-time. In this paper, an energy-efficient link scheduling (ELS) protocol for cognitive radio body area networks (CRBANs) is proposed, which aims to minimize energy consumption in CRBANs, while achieving higher probabilities of successful transmissions with multiple CRBANs. The proposed ELS transmits packets in the common control channel to control transmission links amongst CRBANs to the gateway and vice versa. The transmissions of CRBANs to the gateway are scheduled at a specific time by the gateway in different data channels, according to the traffic priority of CRBANs. Packet delivery ratio, delay, and energy consumption are evaluated for multiple CRBANs via extensive simulation.


Assuntos
Cognição/fisiologia , Algoritmos , Redes de Comunicação de Computadores , Atenção à Saúde/métodos , Eletrônica/métodos , Humanos , Tecnologia sem Fio
8.
Biosens Bioelectron ; 150: 111919, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31787449

RESUMO

Cylindrical fullerenes (or carbon nanotubes (CNTs)) have been extensively investigated as potential sensor platforms due to effective and practical manipulation of their physical and chemical properties by functionalization/doping with chemical groups suitable for novel nanocarrier systems. CNTs play a significant role in biomedical applications due to rapid development of synthetic methods, structural integration, surface area-controlled heteroatom doping, and electrical conductivity. This review article comprehensively summarized recent trends in biomedical science and technologies utilizing a promising nanomaterial of CNTs in disease diagnosis and therapeutics, based on their biocompatibility and significance in drug delivery, implants, and bio imaging. Biocompatibility of CNTs is essential for designing effective and practical electronic applications in the biomedical field particularly due to their growing potential in the delivery of anticancer agents. Furthermore, functionalized CNTs have been shown to exhibit advanced electrochemical properties, responsible for functioning of numerous oxidase and dehydrogenase based amperometric biosensors. Finally, faster signal transduction by CNTs allows charge transfer between underlying electrode and redox centres of biomolecules (enzymes).


Assuntos
Fulerenos/química , Nanotubos de Carbono/química , Animais , Técnicas Biossensoriais/métodos , Sistemas de Liberação de Medicamentos/métodos , Eletrônica/métodos , Humanos , Próteses e Implantes
9.
ACS Appl Mater Interfaces ; 11(50): 46490-46496, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31808331

RESUMO

Transient electronics have dramatically changed inner-body therapy in health care. They stand out because of their harmless dissolution in the human body with no lingering electronic trash. However, high-precision biomedical implants require programmable and serial remedy operations, and controlling the whole-device destruction is not proactive and precise. Thus, a novel biotriggered and temperature-controlled transient electronics fabrication method using elastin-like polypeptides (ELPs) as triggers is proposed. Biocompatible ELPs simply mixed with trace silver nanowire (AgNW) can serve as the "switch" for the electronics to respond to local temperature changes in deionized water, exhibiting an agile response time. A ratio gradient experiment of the ELPs and AgNW shows that more programmable and precise transience properties (initial resistance, ready time, response time, and stable resistance) can be achieved by using a designated proportion. Further, we validated that the 3D-printing-based ELP-triggering transient electronics fabrication method is very simple yet effective for preparing transient wireless charging LEDs. Transient devices comprising ELPs-AgNW and PLGA-Ag respond within 160 s below 10 °C and degrade within a certain period.


Assuntos
Elastina/química , Nanofios/química , Peptídeos/química , Temperatura , Materiais Biocompatíveis/química , Eletrônica/métodos , Humanos , Transição de Fase , Impressão Tridimensional , Prata/química
10.
Proc Natl Acad Sci U S A ; 116(30): 14823-14828, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31289234

RESUMO

Microrobotics extends the reach of human-controlled machines to submillimeter dimensions. We introduce a microrobot that relies on optoelectronic tweezers (OET) that is straightforward to manufacture, can take nearly any desirable shape or form, and can be programmed to carry out sophisticated, multiaxis operations. One particularly useful program is a serial combination of "load," "transport," and "deliver," which can be applied to manipulate a wide range of micrometer-dimension payloads. Importantly, microrobots programmed in this manner are much gentler on fragile mammalian cells than conventional OET techniques. The microrobotic system described here was demonstrated to be useful for single-cell isolation, clonal expansion, RNA sequencing, manipulation within enclosed systems, controlling cell-cell interactions, and isolating precious microtissues from heterogeneous mixtures. We propose that the optoelectronic microrobotic system, which can be implemented using a microscope and consumer-grade optical projector, will be useful for a wide range of applications in the life sciences and beyond.


Assuntos
Micromanipulação/instrumentação , Robótica/instrumentação , Análise de Célula Única/instrumentação , Eletrônica/instrumentação , Eletrônica/métodos , Humanos , Células MCF-7 , Microfluídica/instrumentação , Microfluídica/métodos , Micromanipulação/métodos , Imagem Óptica/instrumentação , Imagem Óptica/métodos , Robótica/métodos , Análise de Célula Única/métodos
11.
Sci Rep ; 9(1): 4103, 2019 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-30923326

RESUMO

Although different studies have shown that diseases such as breast or lung cancer are associated with specific bodily odours, no study has yet tested the possibility that epileptic seizures may be reflected in an olfactory profile, probably because there is a large variety of seizure types. The question is whether a "seizure-odour", that would be transversal to individuals and types of seizures, exists. This would be a pre requisite for potential anticipation, either by electronic systems (e.g., e-noses) or trained dogs. The aim of the present study therefore was to test whether trained dogs, as demonstrated for cancer or diabetes, may discriminate a general epileptic seizure odor (different from body odours of the same person in other contexts and common to different persons). The results were very clear: all dogs discriminated the seizure odour. The sensitivity and specificity obtained were amongst the highest shown up to now for discrimination of diseases. This constitutes a first proof that, despite the variety of seizures and individual odours, seizures are associated with olfactory characteristics. These results open a large field of research on the odour signature of seizures. Further studies will aim to look at potential applications in terms of anticipation of seizures.


Assuntos
Doenças do Cão/fisiopatologia , Epilepsia/fisiopatologia , Convulsões/fisiopatologia , Olfato/fisiologia , Animais , Cães , Eletrônica/métodos , Feminino , Humanos , Odorantes , Sensibilidade e Especificidade
12.
Food Chem ; 286: 395-404, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827624

RESUMO

Rapid analytical methods for screening irradiated foods are required to comply with the approved standards for international trade. Dried shrimps irradiated at 1-7 kGy with gamma rays, electron beam (E-beam), and X-rays were screened with an electronic nose (E-nose) and electronic tongue (E-tongue). The data were compared with those from European standard methods (photostimulated luminescence, PSL) and direct epifluorescent filter technique/aerobic plate count, DEFT/APC). All irradiated shrimp samples were clearly discriminated from the non-irradiated control based on PSL photon count measurements and DEFT/APC microbial enumeration. The volatile patterns and taste attributes of the irradiated (>1 kGy from three sources) and control samples could be distinguished by the E-nose and E-tongue analyses through principal component analysis. Verification through electron spin resonance and thermoluminescence analyses validated screening results. The results indicate that E-sensing techniques showed potential for the rapid screening of irradiated foods like dried shrimps.


Assuntos
Análise de Alimentos/métodos , Irradiação de Alimentos , Frutos do Mar/análise , Espectroscopia de Ressonância de Spin Eletrônica , Nariz Eletrônico , Eletrônica/instrumentação , Eletrônica/métodos , Análise de Alimentos/instrumentação , Raios gama , Medições Luminescentes/métodos , Raios X
13.
Adv Mater ; 30(50): e1804327, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30306662

RESUMO

Soft on-skin electronics have broad applications in human healthcare, human-machine interface, robotics, and others. However, most current on-skin electronic devices are made of materials with limited gas permeability, which constrain perspiration evaporation, resulting in adverse physiological and psychological effects, limiting their long-term feasibility. In addition, the device fabrication process usually involves e-beam or photolithography, thin-film deposition, etching, and/or other complicated procedures, which are costly and time-consuming, constraining their practical applications. Here, a simple, general, and effective approach for making multifunctional on-skin electronics using porous materials with high-gas permeability, consisting of laser-patterned porous graphene as the sensing components and sugar-templated silicone elastomer sponges as the substrates, is reported. The prototype device examples include electrophysiological sensors, hydration sensors, temperature sensors, and joule-heating elements, showing signal qualities comparable to conventional, rigid, gas-impermeable devices. Moreover, the devices exhibit high water-vapor permeability (≈18 mg cm-2 h-1 ), ≈18 times higher than that of the silicone elastomers without pores, and also show high water-wicking rates after polydopamine treatment, up to 1 cm per 30 s, which is comparable to that of cotton. The on-skin devices with such attributes could facilitate perspiration transport and evaporation, and minimize discomfort and inflammation risks, thereby improving their long-term feasiblity.


Assuntos
Eletrônica/métodos , Gases/química , Grafite/química , Fenômenos Fisiológicos da Pele , Temperatura Corporal , Elastômeros/química , Eletrônica/instrumentação , Humanos , Lasers , Permeabilidade , Porosidade , Açúcares/química , Tampões de Gaze Cirúrgicos , Dispositivos Eletrônicos Vestíveis
14.
J Appl Clin Med Phys ; 19(6): 274-281, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30298980

RESUMO

Relative dose measurements with small ionization chambers in combination with an electrometer placed in the treatment room ("internal electrometer") show a large dependence on the polarity used. While this was observed previously for percent depth dose curves (PDDs), the effect has not been understood or preventable. To investigate the polarity dependence of internal electrometers used in conjunction with a small-volume ionization chamber, we placed an internal electrometer at a distance of 1 m from the isocenter and exposed it to different amounts of scattered radiation by varying the field size. We identified irradiation of the electrometer to cause a current of approximately -1 pA, regardless of the sign of the biasing voltage. For low-sensitivity detectors, such a current noticeably distorts relative dose measurements. To demonstrate how the current systematically changes PDDs, we collected measurements with nine ionization chambers of different volumes. As the chamber volume decreased, signal ratios at 20 and 10 cm depth (M20/M10) became smaller for positive bias voltage and larger for negative bias voltage. At the size of the iba CC04 (40 mm³) the difference of M20/M10 was around 1% and for the smallest studied chamber, the iba CC003 chamber (3 mm³), around 7% for a 10 × 10 cm² field. When the electrometer was moved further from the source or shielded, the additional current decreased. Consequently, PDDs at both polarities were brought into alignment at depth even for the 3 mm³ ionization chamber. The apparent polarity effect on PDDs and lateral beam profiles was reduced considerably by shielding the electrometer. Due to normalization the effect on output values was low. When measurements with a low-sensitivity probe are carried out in conjunction with an internal electrometer, we recommend careful monitoring of the particular setup by testing both polarities, and if deemed necessary, we suggest shielding the electrometer.


Assuntos
Eletrônica/instrumentação , Aceleradores de Partículas/instrumentação , Radiometria/instrumentação , Espalhamento de Radiação , Calibragem , Eletrônica/métodos , Humanos , Doses de Radiação
15.
Acc Chem Res ; 51(9): 2237-2246, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30192512

RESUMO

Molecular electronics is at the forefront of interdisciplinary research, offering a significant extension of the capabilities of conventional silicon-based technology as well as providing a possible stand-alone alternative. Bio-inspired molecular electronics is a particularly intriguing paradigm, as charge transfer in proteins/peptides, for example, plays a critical role in the energy storage and conversion processes for all living organisms. However, the structure and conformation of even the simplest protein is extremely complex, and therefore, synthetic model peptides comprising well-defined geometry and predetermined functionality are ideal platforms to mimic nature for the elucidation of fundamental biological processes while also enhancing the design and development of single-peptide electronic components. In this Account, we first present intramolecular electron transfer within two synthetic peptides, one with a well-defined helical conformation and the other with a random geometry, using electrochemical techniques and computational simulations. This study reveals two definitive electron transfer pathways (mechanisms), the natures of which are dependent on secondary structure. Following on from this, electron transfer within a series of well-defined helical peptides, constrained by either Huisgen cycloaddition, ring-closing metathesis, or a lactam bridge, was determined. The electrochemical results indicate that each constrained peptide, in contrast to a linear counterpart, exhibits a remarkable shift of the formal potential to the positive (>460 mV) and a significant reduction of the electron transfer rate constant (up to 15-fold), which represent two distinct electronic "on/off" states. High-level calculations demonstrate that the additional backbone rigidity provided by the side-bridge constraints leads to an increased reorganization energy barrier, which impedes the vibrational fluctuations necessary for efficient intramolecular electron transfer through the peptide backbone. Further calculations reveal a clear mechanistic transition from hopping to superexchange (tunneling) stemming from side-bridge gating. We then extended our research to fine-tuning of the electronic properties of peptides through both structural and chemical manipulation, to reveal an interplay between electron-rich side chains and backbone rigidity on electron transfer. Further to this, we explored the possibility that the side-bridge constraints present in our synthetic peptides provide an additional electronic transport pathway, which led to the discovery of two distinct forms of quantum interferometer. The effects of destructive quantum interference appear essentially through both the backbone and an alternative tunneling pathway provided by the side bridge in the constrained ß-strand peptide, as evidenced by a correlation between electrochemical measurements and conductance simulations for both linear and constrained ß-strand peptides. In contrast, an interplay between quantum interference effects and vibrational fluctuations is revealed in the linear and constrained 310-helical peptides. Collectively, these exciting findings augment our fundamental knowledge of charge transfer dynamics and kinetics in peptides and also open up new avenues to design and develop functional bio-inspired electronic devices, such as on/off switches and quantum interferometers, for practical applications in molecular electronics.


Assuntos
Elétrons , Peptídeos/química , Eletricidade , Técnicas Eletroquímicas/métodos , Eletrônica/métodos , Cinética , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta
16.
Adv Healthc Mater ; 7(16): e1800231, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29947042

RESUMO

Degradable electronics represent a rapidly emerging field of science and technology with the potential to serve short-term medical implantation applications where the device disappears once its function is complete. Despite many efforts in developing new types of degradable electronics, many of such systems are nonelastic and incompatible with the dynamic motion of native soft/elastic biological tissues. Herein, a photo-crosslinkable hydrogel with integrated electronics that are highly stretchable and degradable in liquid environments is demonstrated. The fabrication process takes advantage of facile laser micromachining of conductive patterns directly onto the hydrogel under ambient conditions and permanent hydrogel-hydrogel bonding. The robustness and degradation rate of hydrogel and the laser-processed encapsulated stretchable circuits is systematically investigated in different solutions under various conditions. Biocompatibility tests with non-neoplastic cells (HMT 3522 S1) and cancer cells (T4-2 and MDA-MB-231) are performed in 2D and 3D cell culture systems to confirm instead of evaluate the safety of the hydrogel and its byproducts during degradation as well as the zinc metal used in this technology. As a proof of concept, a stretchable hydrogel-based device that can be used for remote/wireless delivery of thermal energy into the tissue in contact with the hydrogel is fabricated.


Assuntos
Eletrônica/métodos , Hidrogéis/química , Lasers , Linhagem Celular Tumoral , Humanos , Polímeros/química , Zinco/química
17.
Comput Methods Biomech Biomed Engin ; 20(16): 1678-1689, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29164909

RESUMO

Breathing parameters can be measured by motion capture systems by placing photo-reflective markers on the chest wall. A computational model is mandatory to compute the breathing volume and to calculate temporal and kinematical features by the gathered markers trajectories. Despite different methods based on different geometrical approaches can be adopted to compute volumes, no information about their differences in the respiratory evaluation are available. This study investigated the performances of four methods (conventional, prism-based, convex hull with boundary condition, based on Delaunay triangulation) using an optoelectronic motion capture system, on twelve healthy participants during 30 s of breathing. Temporal trends of volume traces, tidal volume values, and breathing durations were compared between methods and spirometry (used as reference instrument). Additionally, thoraco-abdominal motion patterns were compared between methods by analysing the compartmental contributions and their variability. Results shows comparable similarities between the volume traces obtained using spirometry, prism-based and conventional methods. Prism-based and convex hull with boundary condition methods show lower bias in tidal volumes estimation up to 0.06 L, compared to the conventional and Delaunay triangulation methods. Prism-based method shows maximum differences of 30 mL in the comparison of compartmental contributions to the total volume, by resulting in a maximum deviation of 1.6% in the percentage contribution analysis. In conclusion, our finding demonstrated the accuracy of the non-invasive MoCap-based breathing analysis with the prism-based method tested. Data provided in this study will lead researchers and clinicians in the computational method choice for temporal and volumetric breathing analysis.


Assuntos
Abdome/fisiologia , Eletrônica/métodos , Movimento (Física) , Óptica e Fotônica/métodos , Respiração , Tórax/fisiologia , Fenômenos Biomecânicos , Simulação por Computador , Feminino , Humanos , Pulmão/fisiologia , Masculino , Tamanho do Órgão , Pletismografia , Espirometria , Estatística como Assunto , Parede Torácica/fisiologia , Volume de Ventilação Pulmonar/fisiologia , Adulto Jovem
18.
Biomaterials ; 146: 156-167, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28918265

RESUMO

Electrochemical treatment of tumors (EChT) has recently been identified as a very effective way for local tumor therapy. However, hindered by the limited effective area of a single rigid electrode, multiple electrodes are often recruited when tackling large tumors, where too many electrodes not only complicate the clinical procedures but also aggravate patients' pain. Here we present a new conceptual electric stimulation tumor therapy through introducing the injectable liquid metal electrodes, which can adapt to complex tumor shapes so as to achieve desired therapeutic performance. This approach can offer evident merits for dealing with the complex physiological situations, especially for those irregular body cavities like stomach, colon, rectum or even blood vessel etc., which are hard to tackle otherwise. As it was disclosed from the conceptual experiments that, Unlike traditional rigid and uncomfortable electrodes, liquid metal possesses high flexibility to attach to any crooked biological position to deliver and adjust targeted electric field to fulfill anticipated tumor destruction. And such amorphous electrodes exhibit rather enhanced treatment effect of tumors. Further, we also demonstrate that EChT with liquid metal electrodes produced more electrochemical products during electrolysis. Transformations with the shapes of liquid metal provided an easily regulatable strategy to improve EChT efficiency, which can conveniently aid to achieve better output compared to multiple electrodes. In vivo EChT of tumors further clarified the effect of liquid metal electrodes in retarding tumor growth and increasing life spans.


Assuntos
Eletroquímica/métodos , Eletrodos , Eletrônica/métodos , Animais , Terapia por Estimulação Elétrica/métodos , Humanos , Neoplasias/metabolismo
19.
J Exp Ther Oncol ; 12(1): 83-85, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28472569

RESUMO

OBJECTIVE: This paper presents a theory and system on "Cancer-Meter'. This idea came through the statement that "cancer is curable if it is measurable". The Cancer-Meter proves that it is possible. This paper proposes the cancer-meter in two ways, theoretical and electronically, as per the measurement and treatment. By the mathematics, first part is defined but the second part is based on computer programming, electrical and electronics. Thus, the cancer-meter is a programmed-electrical-electronic device which measures and cures the cancer both.


Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/terapia , Eletrônica/métodos , Humanos , Matemática/métodos , Software
20.
PLoS One ; 12(4): e0175430, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28414730

RESUMO

OBJECTIVE: Our purpose was to quantify 36 inorganic chemical elements in aerosols from disposable electronic cigarettes (ECs) and electronic hookahs (EHs), examine the effect of puffing topography on elements in aerosols, and identify the source of the elements. METHODS: Thirty-six inorganic chemical elements and their concentrations in EC/EH aerosols were determined using inductively coupled plasma optical emission spectroscopy, and their source was identified by analyzing disassembled atomizers using scanning electron microscopy and energy dispersive X-ray spectroscopy. RESULTS: Of 36 elements screened, 35 were detected in EC/EH aerosols, while only 15 were detected in conventional tobacco smoke. Some elements/metals were present in significantly higher concentrations in EC/EH aerosol than in cigarette smoke. Concentrations of particular elements/metals within EC/EH brands were sometimes variable. Aerosols generated at low and high air-flow rates produced the same pattern of elements, although the total element concentration decreased at the higher air flow rate. The relative amount of elements in the first and last 60 puffs was generally different. Silicon was the dominant element in aerosols from all EC/EH brands and in cigarette smoke. The elements appeared to come from the filament (nickel, chromium), thick wire (copper coated with silver), brass clamp (copper, zinc), solder joints (tin, lead), and wick and sheath (silicon, oxygen, calcium, magnesium, aluminum). Lead was identified in the solder and aerosol of two brands of EHs (up to 0.165 µg/10 puffs). CONCLUSION: These data show that EC/EH aerosols contain a mixture of elements, including heavy metals, with concentrations often significantly higher than in conventional cigarette smoke. While the health effects of inhaling mixtures of heated metals is currently not known, these data will be valuable in future risk assessments involving EC/EH elements/metals.


Assuntos
Aerossóis/análise , Compostos Inorgânicos/química , Metais/química , Cromo/química , Cobre/química , Sistemas Eletrônicos de Liberação de Nicotina/métodos , Eletrônica/métodos , Nebulizadores e Vaporizadores , Níquel/química , Nicotina/química , Prata/química , Fumaça/análise , Espectrometria por Raios X/métodos , Nicotiana/anatomia & histologia , Zinco/química
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