Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 132
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4563-4566, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019009

RESUMO

Wearable sensors enable the simultaneous recording of several electrophysiological signals from the human body in a non-invasive and continuous manner. Textile sensors are garnering substantial interest in the wearable technology because they can be knitted directly into the daily-used objects like underwear, bra, dress, etc. However, accurate processing of signals recorded by textile sensors is extremely challenging due to the very low signal-to-noise ratio (SNR). Systematic classification of textile sensor noise (TSN) is necessary to: (i) identify different types of noise and their statistical characteristics, (ii) explore how each type of noise influences the electrophysiological signal, (iii) develop optimal textile-specific electronics that suppress TSN, and (iv) reproduce TSN and create large dataset of textile sensors to validate various machine learning and signal processing algorithms. In this paper, we develop a novel technique to classify textile sensor artifacts in ECG signals. By simultaneously recording signals from the waist (textile sensors) and chest (gel electrode), we extract TSN by removing the chest ECG signal from the recorded textile data. We classify TSN based on its morphological and statistical features in two main categories, namely, slow and fast. Linear prediction coding (LPC) is utilized to model each class of TSN by auto-regression coefficients and residues. The residual signal can be approximated by Gaussian distribution which enables reproducing slow and fast artifacts that not only preserve the similar morphological features but also fulfill the statistical properties of TSN. By reproducing TSN and adding them to clean ECG signals, we create a textile-like ECG signal which can be used to develop and validate different signal processing algorithms.


Assuntos
Dispositivos Eletrônicos Vestíveis , Artefatos , Humanos , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Têxteis
2.
Analyst ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33030164

RESUMO

Compared to general fluorescent probes, multi-photon fluorescent probes exhibit deeper tissue penetration, lower auto-fluorescence and lower photo-toxicity in the bio-imaging field. Herein, we synthesized a series multi-photon fluorescent probe (L1-L3) based on quinolone groups. Of notably, the three-photon fluorescence of L3 significantly enhanced when L3 interacted with liposome; moreover, L3 exhibited high selectivity towards lipid droplets in living cells. Due to its large Stokes shift, high selectivity and photon-stability, L3 was successfully used in lipid droplet imaging via multi-photon fluorescence bio-imaging.

3.
Inorg Chem ; 59(18): 13671-13678, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32857510

RESUMO

The construction of novel classes of photosensitizers for efficient reactive oxygen species (ROS) generation is of great interest, yet it is a challenge. In this work, a bis(terpyridine)zinc(II) complex (namely, ZnL1) with two-photon absorption activity as an efficient ROS photogenerator was synthesized. Benefiting from the coordinated Zn, the decreased singlet-triplet energy gap favors the intersystem crossing process facilitating the singlet oxygen (1O2) generation via energy transfer. In addition, it makes the superoxide radical (O2·-) generation easier. This is an extremely rare study on two-photon excited ROS generation by activating type I and type II processes based on a cheaper and bioaccessible Zn complex.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32815192

RESUMO

The visualization of microtubules by combining optical and electron microscopy techniques provides valuable information to understand correlated intracellular activities. However, the lack of appropriate probes to bridge both microscopic resolutions restricts the areas and structures that can be comprehended within such highly assembled structures. Here, a versatile cyclometalated iridium (III) complex is designed that achieves synchronous fluorescence-electron microscopy correlation. The selective insertion of the probe into a microtubule triggers remarkable fluorescence enhancement and promising electron contrast. The long-life, highly photostable probe allows live-cell super-resolution imaging of tubulin localization and motion with a resolution of ≈30 nm. Furthermore, correlative light-electron microscopy and energy-filtered transmission electron microscopy reveal the well-associated optical and electron signal at a high specificity, with an interspace of ≈41 Å of microtubule monomer in cells.

5.
Anal Chem ; 92(15): 10815-10821, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32615754

RESUMO

Cell viability is greatly affected by external stimulus eliciting correlated dynamical physiological processes for cells to choose survival or death. A few fluorescent probes have been designed to detect whether the cell is in survival state or apoptotic state, but monitoring the regulation process of the cell undergoing survival to death remains a long-standing challenge. Herein, we highlight the in situ monitor of mitochondria regulating the cell viability by the RNA-specific fluorescent photosensitizer L. At normal conditions, L anchored mitochondria and interacted with mito-RNA to light up the mitochondria with red fluorescence. With external light stimulus, L generated reactive oxide species (ROS) and cause damage to mitochondria, which activated mitochondrial autophagy to prevent death, during which the red fluorescence of L witnessed dynamical distribution in accordance with the evolution of vacuole structures containing damaged mitochondria into autophagosomes. However, with ROS continuously increasing, the mitochondrial apoptosis was eventually commenced and L with red fluorescent was gradually accumulated in the nucleoli, indicating the programmed cell death. This work demonstrated how the delicate balance between survival and death are regulated by mitochondria.

6.
Biomed Eng Online ; 19(1): 48, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546233

RESUMO

BACKGROUND: The development of wearable health monitoring systems is garnering tremendous interest in research, technology and commercial applications. Their ability of providing unique capabilities in continuous, real-time, and non-invasive tracking of the physiological markers of users can provide insights into the performance and health of individuals. Electrocardiogram (ECG) signals are of particular interest, as cardiovascular disease is the leading cause of death globally. Monitoring heart health and its conditions such as ventricular disturbances and arrhythmias can be achieved through evaluating various features of ECG such as R-peaks, QRS complex, T-wave, and P-wave. Despite recent advances in biosensors for wearable applications, most of the currently available solutions rely solely on a single system attached to the body, limiting the ability to obtain reliable and multi-location biosignals. However, in engineering systems, sensor fusion, which is the optimal integration and processing of data from multiple sensors, has been a common theme and should be considered for wearables. In recent years, due to an increase in the availability and variety of different types of sensors, the possibility of achieving sensor fusion in wearable systems has become more attainable. Sensor fusion in multi-sensing systems results in significant enhancements of information inferences compared to those from systems with a sole sensor. One step towards the development of sensor fusion for wearable health monitoring systems is the accessibility to multiple reliable electrophysiological signals, which can be recorded continuously. RESULTS: In this paper, we develop a textile-based multichannel ECG band that has the ability to measure ECG from multiple locations on the waist. As a proof of concept, we demonstrate that ECG signals can be reliably obtained from different locations on the waist where the shape of the QRS complex is nearly comparable with recordings from the chest using traditional gel electrodes. In addition, we develop a probabilistic approach-based on prediction and update strategies-to detect R-peaks from noisy textile data in different statuses, including sitting, standing, and jogging. In this approach, an optimal search method is utilized to detect R-peaks based on the history of the intervals between previously detected R-peaks. We show that the performance of our probabilistic approach in R-peak detection is significantly better than that based on Pan-Tompkins and optimal-threshold methods. CONCLUSION: A textile-based multichannel ECG band was developed to track the heart rate changes from multiple locations on the waist. We demonstrated that (i) the ECG signal can be detected from different locations on the waist, and (ii) the accuracy of the detected R-peaks from textile sensors was improved by using our proposed probabilistic approach. Despite the limitations of the textile sensors that might compromise the quality of ECG signals, we anticipate that the textile-based multichannel ECG band can be considered as an effective wearable system to facilitate the development of sensor fusion methodology for pervasive and non-invasive health monitoring through continuous tracking of heart rate variability (HRV) from the waist. In addition, from the commercialization point of view, we anticipate that the developed band has the potential to be integrated into garments such as underwear, bras or pants so that individuals can use it on a daily basis.

7.
Small ; 16(19): e2000680, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32285624

RESUMO

Carbon dots (CDs), with excellent optical property and cytocompatibility, are an ideal class of nanomaterials applied in the field of biomedicine. However, the weak response of CDs in the near-infrared (NIR) region impedes their practical applications. Here, UV-vis-NIR full-range responsive fluorine and nitrogen doped CDs (N-CDs-F) are designed and synthesized that own a favorable donor-π-acceptor (D-π-A) configuration and exhibit excellent two-photon (λex = 1060 nm), three-photon (λex = 1600 nm), and four-photon (λex = 2000 nm) excitation upconversion fluorescence. D-π-A-conjugated CDs prepared by solvothermal synthesis under the assistance of ammonia fluoride are reported and are endowed with larger multiphoton absorption (MPA) cross sections (3PA: 9.55 × 10-80 cm6 s2 photon-2 , 4PA: 6.32 × 10-80 cm8 s3 photon-3 ) than conventional organic compounds. Furthermore, the N-CDs-F show bright deep-red to NIR fluorescence both in vitro and in vivo, and can even stain the nucleoli of tumor cells. A plausible mechanism is proposed on the basis of the strong inter-dot and intra-dot hydrogen bonds through NH···F that can facilitate the expanding of conjugated sp2 domains, and thus not only result in lower highest occupied molecular orbital-lowest unoccupied molecular orbital energy level but also larger MPA cross sections than those of undoped CDs.

8.
Sensors (Basel) ; 20(5)2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143333

RESUMO

An Ag/AgCl electrode used as a corrosion sensor in a reinforced concrete structure isconsidered as having good application prospect. However, its performance under complexconditions, such as dry-wet cycle condition, is not affirmed. In the current study, the performanceof Ag/AgCl as chloride selective electrode in mortar exposed to dry-wet cycle condition wasinvestigated. A simple Ag/AgCl electrode was prepared and fabricated by electrochemicalanodization. These Ag/AgCl electrodes were embedded into a mortar specimen with temperaturesensors, humidity sensors and anode ladder monitoring system (ALS). After 28 d curing time, theupper surface of mortar specimen was wetted (with 5% NaCl solution) and dried regularly. Theobtained results indicate that Ag/AgCl electrode responds to the ingress of chloride ion, sensitively.The chloride ion concentration variation can be reflected by the potential trend. Furthermore, thebalance potential of Ag/AgCl electrodes is influenced by dry-wet cycles. Compared with ALS, itdemonstrates that Ag/AgCl electrodes are more sensitive to chloride. The research provides the keyelement for the specific application of Ag/AgCl electrode for corrosion monitoring in the future.

9.
Chem Commun (Camb) ; 56(12): 1859-1862, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31950954

RESUMO

We present the design and synthesis of water-soluble quinoline-indole-based derivatives (IM-1, IM-2, and IM-3) with three-photon absorption activity. IM-3 can specifically target DNA and RNA accompanied by an obvious three-photon fluorescence enhancement in the second near-infrared window (1000-1700 nm). The in vitro experiments demonstrate that IM-3 can simultaneously stain mitochondria and the nucleolus both in living and fixed cells. The organelle-specific targeting behaviour is successfully visualized under stimulated emission depletion (STED) nanoscopy.


Assuntos
DNA Mitocondrial/análise , Corantes Fluorescentes/química , Indóis/química , Fótons , Quinolinas/química , RNA Neoplásico/análise , Nucléolo Celular/química , Células Hep G2 , Humanos , Estrutura Molecular , Imagem Óptica , Solubilidade , Água/química
10.
Chemistry ; 26(17): 3834-3842, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-31944424

RESUMO

Organic mechanofluorochromic (MFC) materials with mechanical-induced emission enhancement (MIEE) are scarce. Herein, Aggregation-induced emission (AIE)-active tetraphenylethene-functionalised pyrazoline derivatives with various non-conjugated substituent groups (Br, F, N,N-dimethylamino and cyano groups for TPEB, TPEF, TPEN and TPECN, respectively) were designed and synthesised. The fluorescence spectra of the compounds in the solid state were sensitive to mechanical stimuli and exhibited unique MFC properties. The solid fluorescence peaks of all compounds were red shifted, whereas the quantum yields of TPEB, TPEF and TPEN were increased and that of TPECN was slightly reduced after grinding. The MIEE mechanism was systematically investigated through structure-property relationship studies. The results showed that the pyrazoline ring of TPEB with MIEE property formed H-dimer aggregates with weak π-π stacking in the solid state. After grinding, the synergistic effects of conformational planarization and destructive π-π interactions induced the red shift of the fluorescence peak and the intensity enhanced. TPECN formed incompact J-aggregates with weak intermolecular interactions instead. The conformational planarization and increased intermolecular interactions induced by grinding led to the red-shifted peak and the slightly reduced intensity. These results clearly demonstrated that the translation of packing arrangements is an efficient method to design MIEE materials, which opens a new scope for designing unique MFC materials.

11.
ACS Appl Mater Interfaces ; 12(2): 1988-1996, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31771326

RESUMO

Photodynamic therapy (PDT) takes advantage of reactive oxygen species (ROS) to trigger the apoptosis for cancer therapy. Given that cell apoptosis is a form of programmed cell death involved with multiple suborganelles and cancer cells are more sensitive to ROS than normal cells, early confirmation of the apoptosis induced by ROS would effectively avoid overtreatment. Herein, we highlight an aggregation-induced emission (AIE)-based theranostic agent (TPA3) to in situ dynamically track mitophagy prior to late apoptosis. TPA3 showed high specificity to autophagy vacuoles (AVs), of which appearance is the signature event of mitophagy during early apoptosis and delivered photocytotoxicity to cancer cells and skin cancer tumors in nude mice under irradiation of white light. Furthermore, in situ monitoring of the dynamical mitophagy process involved with mitochondria, AVs, and lysosomes was performed for the first time under confocal microscopy, providing a real-time self-monitoring system for assessing the curative effect prior to late apoptosis. This fluorescence imaging guided PDT witness great advances for applying in the clinical application.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117766, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31718977

RESUMO

Lipid droplets (LDs) are organelles featuring in intracellular storage of neutral lipids, which are involved with many biological processes. Monitoring the dynamical cyclic behaviors of cellular LDs poses great importance for early disease diagnosis. Herein, two coumarin-based LDs-specific fluorescence probes exhibited "turn-on" and two-photon fluorescence triggered by breaking their aggregation states. By virtue of establishing oil/water emulsions model to simulate LDs, the behaviors of "turn-on" fluorescence were elucidated, which benefited for the enhancement of selectivity of the probes to LDs. Then, we highlight a LDs-specific coumarin-based two-photon probe (L1) with high photo-stability to monitor the dynamic cyclic behaviors of LDs in cells, unraveling the changes of LDs quantity during lipophagy and the reproduction of LDs to prevent lipotoxicity. We believe the probe offers a convenient way to investigate the biology of LDs.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 226: 117571, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31622830

RESUMO

The fabrication of two-photon absorption material is a versatile approach to achieve high resolution bioimaging with low phototoxicity yet remain sophisticated. Herein, a zwitterionic chromophore, MF, with D-π-A configuration has been rational designed and synthesized. Remarkably, MF exhibited enhanced one- and two-photon fluorescent in the aggregation states. Additionally, the obtained MFNPs encapsulated by Pluronic F-127, could be employed as a two-photon fluorescent probe for bioimaging. The results reveal that MFNPs could target mitochondria by using two-photon confocal microscopy and stimulated emission depletion nanoscopy methods.

14.
Materials (Basel) ; 12(21)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31731435

RESUMO

Recently, there is ongoing interest in the use of natural plant fibers as alternatives for conventional reinforcements in cementitious composites. The use of natural plant fibers makes engineering work more sustainable, since they are renewable, biodegradable, energy-efficient, and non-toxic raw materials. In this contribution, a comprehensive experimental program was undertaken to determine the influence of pineapple leaf fiber and ramie fiber on the mechanical properties and mass transport of cement-based composites. The compressive strength, tensile strength, modulus of elasticity, modulus of rupture, fracture energy, flexural toughness, coefficient of capillary water absorption, and chloride diffusion were measured. Natural plant fiber-reinforced cement-based composites (NPFRCCs) containing pineapple leaf fiber and ramie fiber, as compared to the plain control, exhibited a slight reduction in compressive strength and a considerable improvement in tensile strength, modulus of elasticity, modulus of rupture, and flexural toughness; the enhancement was remarkable with a higher fiber content. The coefficient of capillary absorption and chloride diffusion of NPFRCCs were significantly larger than the plain control, and the difference was evident with the increase in fiber content. The present study suggests that the specimen with 2% pineapple leaf fiber content can be used in normal environments due to its superior mechanical properties. However, one should be careful when using the material in marine environments.

15.
Chem Sci ; 10(30): 7228-7232, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31588291

RESUMO

Multiphoton bioimaging benefits from good penetration of tissue, low phototoxicity and high resolution. Hence, development of efficient multiphoton imaging agents is highly desirable but remains challenging. Herein, a novel terpyridine-based Zn(ii) complex bearing a thiophene bridge was designed rationally and fabricated. Thanks to its aggregation-induced emission (AIE), DZ1 emitted bright yellow-green fluorescence (λ em = 575 nm) under physiological conditions. The three-photon spectral changes of DZ1 when binding with RNA unambiguously reflected its RNA-specific targeting behaviour, resulting in twofold enhancement in three-photon action cross-sections located at the second near-infrared window (1700 nm).

16.
Theranostics ; 9(8): 2158-2166, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31149035

RESUMO

Platinum complexes have been used for anti-cancer propose for decades, however, their high side effects resulting from damage to healthy cells cannot be neglected and prevent further clinical utilisation. Here, we designed a cyclometalated platinum (II) complex that can bind the endogenous nuclear factor-κB (NF-κB) protein. Employing detailed colocalization studies in co-culture cell line models, we show that by binding to NF-κB, the platinum (II) complex is capable of upregulated nuclear translocation specifically in cancer but not normal cells, thereby impairing cancer proliferation without disturbing healthy cells. In a murine tumour model, the platinum (II) complex prevents tumour growth to a greater extent than cisplatin and with considerably lower side-effects and kidney damage. Considering its weak damage to normal cells combined with high toxicity to cancer cells, this NF-κB-binding platinum complex is a potential anti-cancer candidate and acts to verify the strategy of hijacking endogenous trans-nuclear proteins to achieve cancer-cell specificity and enhance therapeutic indices.

17.
ACS Appl Mater Interfaces ; 11(20): 18203-18212, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31026133

RESUMO

Commercial gadolinium-based materials have been widely used as contrast agents for magnetic resonance imaging (MRI), but the high toxicity of leaking free Gd3+ ions still raises biosafety concerns. Here, we develop a novel, safe, and efficient MRI contrast agent based on a stable Fe(III) complex of fluorine and nitrogen co-doped carbon dots (F,N-CDs) that was prepared from glucose and levofloxacin by a simple microwave-assisted thermal decomposition method. The obtained Fe3+@F,N-CD complex exhibits higher longitudinal relaxivity ( r1 = 5.79 mM-1·s-1) than that of the control samples of the Fe3+@CD complex ( r1 = 4.23 mM-1 s-1) and free Fe3+ ( r1 = 1.59 mM-1 s-1) in aqueous solution, as assessed by a 1.5 T NMR analyzer. More importantly, the Fe3+@F,N-CD complex is very stable with a large coordination constant of 1.06 × 107 in aqueous medium. While incubated with HeLa cells, the Fe3+@F,N-CD complex shows clear MR images, demonstrating that it has potential to be an excellent MRI contrast agent. Furthermore, in vivo MRI experiments indicate that the Fe3+@F,N-CD complex provides high-resolution MRI pictures of 4T1 tumor bearing BALB/c mice 15 min after injection and can be completely excreted 2 h after administration. No cytotoxicity was observed with F,N-CDs and Fe concentration up to 0.2 mg/mL and 0.3 mM in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell proliferation assay, respectively. The possible mechanism of the enhanced MRI effect of the Fe3+@F,N-CD complex is therefore proposed. The extremely low toxicity, high r1 relaxivity, strong photoluminescence, and low synthetic cost enable the Fe3+@F,N-CD complex to be a safe and promising T1-weighted MRI contrast agent for clinical applications.


Assuntos
Carbono , Meios de Contraste , Compostos Férricos , Flúor , Imagem por Ressonância Magnética , Nanopartículas , Neoplasias Experimentais/diagnóstico por imagem , Nitrogênio , Animais , Carbono/química , Carbono/farmacologia , Meios de Contraste/química , Meios de Contraste/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacologia , Flúor/química , Flúor/farmacologia , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Nitrogênio/química , Nitrogênio/farmacologia
18.
Anal Chem ; 91(10): 6730-6737, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31001974

RESUMO

Unveiling the synergism among multiple organelles for fully exploring the mysteries of the cell has drawn more and more attention. Herein, we developed two two-photon fluorescent bioprobes (Lyso-TA and Mito-QA), of which the conformational change triggered an "off-on" fluorescent response. Lyso-TA can real-time monitor the fusion and movement of lysosomes as well as unveil the mitophagy process with the engagement of lysosomes. Mito-QA was transformed from Lyso-TA by one-step ambient temperature reaction, visualizing the dysfunctional mitochondria through a shift from mitochondria to nucleoli. With superior two-photon absorption cross section, good biocompatibility, and greater penetration depth, two small bioprobes were both applied in in vivo bioimaging of brain tissues and zebrafish.

19.
Talanta ; 199: 140-146, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952238

RESUMO

Small molecules emitting in the NIR for tracking mitochondrial pH alteration with super-resolution are expected to play an essential role in biomedical applications. Herein, two small molecules based on pyridinium salt (P1 and P2) have been synthesized and systematically investigated. It was found that pyridinium salts P1 and P2 emitted in the NIR (about 610 nm), which could detect pH changes from 2.0 to 11.0 with good linearity and high sensitivity. Importantly, P2 could precisely target cellular mitochondria in a real-time manner under stimulated emission depletion (STED). These results implied a chemical strategy with a potential application in super-resolution imaging and mitochondrial pH determination.


Assuntos
Mitocôndrias/química , Compostos de Piridínio/química , Bibliotecas de Moléculas Pequenas/química , Cristalografia por Raios X , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Raios Infravermelhos , Microscopia de Fluorescência , Modelos Moleculares , Estrutura Molecular , Compostos de Piridínio/síntese química , Teoria Quântica , Bibliotecas de Moléculas Pequenas/síntese química
20.
Dalton Trans ; 48(5): 1900-1905, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30652713

RESUMO

In this study, by employing mixed organic ligands through rational design and metal ions as the initial reactants, a series of novel metal-organic frameworks (AHU-TW1 to 6) were synthesized by a solvothermal method. Herein, accessible Lewis base sites originating from organic ligands within MOFs act as functional sites that can interact with the analyte possessing protons and then lead to obvious variations in the fluorescence spectra. Due to their superiority, AHU-TW1, 3, 4 and 6 are able to recognize trinitrophenol (TNP) with high sensitivity and a low detection limit.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA