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1.
Int J Biol Macromol ; 256(Pt 1): 128392, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029917

RESUMO

The increased mortality rates associated with colorectal cancer highlight the pressing need for improving treatment approaches. While capsaicin (CAP) has shown promising anticancer activity, its efficacy is hampered due to low solubility, rapid metabolism, suboptimal bioavailability, and a short half-life. Therefore, this study aimed to prepare a lactoferrin-functionalized carboxymethyl dextran-coated egg albumin nanoconjugate (LF-CMD@CAP-EGA-NCs) for the targeted CAP delivery to enhance its potential for colorectal cancer therapy. Briefly, LF-CMD was synthesized through an esterification reaction involving LF as a receptor and CMD as a shell. Concurrently, CAP was incorporated into an EGA carrier using gelation and hydrophobic interactions. The subsequent production of LF-CMD@CAP-EGA-NCs was achieved through the Maillard reaction. Spectral characterizations confirmed the successful synthesis of smooth and spherical-shaped LF-CMD@CAP-EGA-NCs using LF-CMD and EGA-CAP nanoparticles, with high entrapment efficiency and satisfactory drug content. Furthermore, LF-CMD@CAP-EGA-NCs demonstrated a sustained release of CAP (76.52 ± 1.01 % in 24 h, R2 = 0.9966) in pH 5.8 buffer with anomalous transport (n = 0.68) owing to the shell of the CMD and EGA matrix. The nanoconjugate exhibited enhanced cytotoxicity in HCT116 and LoVo cell lines, which is attributed to the overexpression of LF receptors in colorectal HCT116 cells. Additionally, LF-CMD@CAP-EGA-NCs demonstrated excellent biocompatibility, as observed in the FHC-CRL-1831 cell line. In conclusion, LF-CMD@CAP-EGA-NCs can be considered as a promising approach for targeted delivery of CAP and other anticancer agents in colorectal cancer treatment.


Assuntos
Neoplasias Colorretais , Dextranos , Nanopartículas , Humanos , Nanoconjugados , Lactoferrina/farmacologia , Lactoferrina/química , Capsaicina , Nanopartículas/química , Neoplasias Colorretais/tratamento farmacológico
2.
Anal Sci ; 40(6): 1177-1191, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38554251

RESUMO

Despite the high medicinal value of tiopronin, there are substantial adverse effects such as yellow skin, yellow eyes, muscle aches, etc. Therefore, there is a huge necessity to identify tiopronin using advanced sensors in provided samples. Recently, the preference for graphene quantum dots (GQDs) and inorganic nanomaterial-based fluorescent sensors for the detection of pharmaceuticals has been extensively documented due to their plentiful advantages. Therefore, in this work, the cobalt-doped GQDs decorated vanadium pentoxide nanosheet-based fluorescence switch 'Off-On' sensor (Co-GQDs@V2O5-NS) was designed for highly sensitive and selective detection of tiopronin. Briefly, the green synthesis of highly fluorescent Co-GQDs was carried out using a hydrothermal method. Meanwhile, the synthesis of V2O5-NS was synthesized using the liquid exfoliation method. The synthesis of Co-GQDs@V2O5-NS was accomplished wherein Co-GQDs adsorbed on the surface of V2O5-NS that offered the quenching of fluorescence of Co-GQDs. Afterward, the addition of tiopronin into the quenched probe disclosed the proportional recovery of fluorescence of Co-GQDs. Here, the addition of tiopronin provides the decomposition of V2O5-NS and conversion into the V4+ that aids in releasing the quenched fluorescence of Co-GQDs. The limit of detection and linearity range for tiopronin was found to be 1.43 ng/mL and 10-700 ng/mL, respectively. Moreover, it demonstrated high selectivity, good stability at experimental conditions, and practicality in analyzing tiopronin in spiked sample analysis. Hence, the designed Co-GQDs@V2O5-NS nanosized sensor enables high sensitivity, selectivity, simplicity, label-free, and eco-friendly tiopronin recognition. In the future, the utility of Co-GQDs@V2O5-NS can open a new door for sensing tiopronin in provided samples.


Assuntos
Cobalto , Grafite , Nanoestruturas , Pontos Quânticos , Espectrometria de Fluorescência , Compostos de Vanádio , Pontos Quânticos/química , Grafite/química , Cobalto/química , Compostos de Vanádio/química , Nanoestruturas/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Limite de Detecção
3.
J Biomol Struct Dyn ; : 1-14, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38260958

RESUMO

We designed a highly sensitive fluorescent sensor for the early detection of sarcosine, a potential biomarker for prostate cancer. This sensor was based on surface-cobalt-doped fluorescent carbon quantum dots (Co-CD) using a FRET-based photoluminescent sensing platform. Blue luminescent carbon quantum dots (CQD) were synthesised through a hydrothermal approach, utilizing Delonix regia tree pod shells. Cobalt was employed to functionalize the CQD, enhancing the quantum-entrapped effects and minimizing surface flaws. To optimize Co-CD preparation, we employed a Box-Behnken design (BBD), and response surface methodology (RSM) based on single-factor experiments. The Co-CD was then used as a fluorescent probe for selective Cu2+ detection, with Cu2+ quenching Co-CD fluorescence through an energy transfer process, referred to as 'turn-off'. When sarcosine was introduced, the fluorescence intensity of Co-CD was restored, creating a 'turn-on' response. The sensor exhibited a Cu2+ detection limit (LOD) of 2.4 µM with a linear range of 0 µM to 10 µM. The sarcosine detection in phosphate buffer saline (PBS, pH 7.4) resulted in an LOD of 1.54 µM and a linear range of 0 to 10 µM. Importantly, the sensor demonstrated its suitability for clinical analysis by detecting sarcosine in human urine. In summary, our rapid and highly sensitive sensor offers a novel approach for the detection of sarcosine in real samples, facilitating early prostate cancer diagnosis.Communicated by Ramaswamy H. Sarma.

4.
Biosens Bioelectron ; 139: 111324, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31121435

RESUMO

Surface plasmon resonance (SPR) offers exceptional advantages such as label-free, in-situ and real-time measurement ability that facilitates the study of molecular or chemical binding events. Besides, SPR lacks in the detection of various binding events, particularly involving low molecular weight molecules. This drawback ultimately resulted in the development of several sensitivity enhancement methodologies and their application in the various area. Among graphene materials, graphene-based nanocomposites stands out owing to its significant properties such as strong adsorption of molecules, signal amplification by optical, high carrier mobility, electronic bridging, ease of fabrication and therefore, have established as an important sensitivity enhancement substrate for SPR. Also, graphene-based nanocomposites could amplify the signal generated by plasmon material and increase the sensitivity of molecular detection up to femto to atto molar level. This review focuses on the current important developments made in the potential research avenue of SPR and fiber optics based SPR for chemical and biological sensing. Latest trends and challenges in engineering and applications of graphene-based nanocomposites enhanced sensors for detecting minute and low concentration biological and chemical analytes are reviewed comprehensively. This review may aid in futuristic designing approaches and application of grapheneous sensor platforms for sensitive plasmonic nano-sensors.


Assuntos
Técnicas Biossensoriais , Grafite/química , Nanocompostos/química , Ressonância de Plasmônio de Superfície , Adsorção , Tecnologia de Fibra Óptica
5.
Ultrasound Med Biol ; 34(9): 1504-12, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18407400

RESUMO

The biaxial anisotropy of integrated backscatter from aortic valve cusps was characterized ex vivo as an initial assessment of the suitability of high-frequency ultrasound for nondestructive evaluation of fiber alignment in tissue-engineered heart valves. Apparent integrated backscatter (AIB) from eight fresh, intact porcine cusps was measured over an 80 degrees range of insonification angles using a 40-MHz ultrasound system. Angular dependence of backscatter was characterized by fitting a sinusoid to plots of AIB versus insonification angle for data acquired while rotating the transducer about the cusps in the circumferential and radial directions. Angular variations in backscatter were detected along both directions in individual specimens, although the mean amplitude of the fitted sinusoid was significantly greater for the circumferential data (12.1 +/- 2.6 dB) than the radial data (3.5 +/- 3.1 dB, p = 0.002). The higher angular variation of backscatter in the circumferential direction implies that collagen fibers in the fibrosa layer are the most prominent source of high-frequency scattering from porcine aortic valve cusps. The ability to characterize anisotropic backscattering from individual specimens demonstrates that high-frequency ultrasound can be used for nondestructive evaluation of fiber alignment in heart valve biomaterials.


Assuntos
Algoritmos , Valva Aórtica/diagnóstico por imagem , Próteses Valvulares Cardíacas , Animais , Anisotropia , Bioprótese , Espalhamento de Radiação , Suínos , Ultrassonografia
6.
J Heart Valve Dis ; 15(3): 441-5, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16784086

RESUMO

BACKGROUND AND AIM OF THE STUDY: The study aim was to compare prospectively the clinical performance and long-term durability of the Medtronic Mosaic and Carpentier-Edwards porcine (CE-SAV) bioprostheses in the aortic position over 10 years. METHODS: Between January 2001 and July 2003, a total of 242 patients undergoing bioprosthetic aortic valve replacement (AVR) were prospectively randomized to receive either Medtronic Mosaic (n = 126) or CE-SAV (n = 116) valves, and followed up annually. RESULTS: The mean follow up period was 1.7 +/- 0.8 years; total follow up was 411 patient-years. Early mortality and 40-month actuarial survival were 5.5% and 93 +/- 1% for the Mosaic valve, and 2.6% and 90 +/- 1% for the CE-SAV. Among patients, 78% showed symptomatic improvement in their NYHA functional class after AVR. To date there have been no structural failures, and one patient required reoperation for prosthetic valve (Mosaic) endocarditis. Early thromboembolic events occurred in 2.9% of patients (two Mosaic, five CE-SAV). Echocardiographic evaluations between the two valves demonstrated comparable hemodynamic performance for a given size at one year after surgery. CONCLUSION: At this stage of the study there were no differences in clinical or hemodynamic outcome in patients undergoing AVR using either the Mosaic or CE-SAV porcine xenograft.


Assuntos
Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Desenho de Equipamento , Seguimentos , Frequência Cardíaca , Implante de Prótese de Valva Cardíaca/mortalidade , Hemodinâmica , Humanos , Pessoa de Meia-Idade , Análise de Sobrevida , Sobreviventes , Suínos , Resultado do Tratamento
7.
J Magn Reson Imaging ; 29(4): 825-31, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19306405

RESUMO

PURPOSE: To use magnetic resonance imaging (MRI) to identify and monitor early aortic valve sclerosis (AVS) induced by cholesterol feeding in rabbits. AVS is a highly prevalent disease process, affecting more than 25% of the population over age 65. A major obstacle to early stage medical management of AVS has been the lack of an objective noninvasive technique to identify its presence and monitor its progress. MATERIALS AND METHODS: Retrospectively gated CINE fast spoiled gradient echo (fSPGR) images of aortic valve cusps were collected at 3-month intervals starting at 6 months using a 1.5 T MR scanner interfaced with a customized surface radiofrequency coil. At 16 months a subset of animals was sacrificed and excised cusps were examined with both high frequency ultrasound (US) and histopathological techniques to validate the MRI method. RESULTS: MR and US analysis identified significant thickening of diseased AV cusps when compared to control (P < 0.05). Histopathological analysis confirmed the presence of human-like AVS in diseased rabbit valves. CONCLUSION: Early AVS, exemplified by increased valve thickness, can be identified in vivo using high-resolution MRI.


Assuntos
Doenças da Aorta/diagnóstico , Aterosclerose/diagnóstico , Colesterol na Dieta/metabolismo , Colesterol/metabolismo , Hipercolesterolemia/diagnóstico , Imagem Cinética por Ressonância Magnética/métodos , Análise de Variância , Animais , Processamento de Imagem Assistida por Computador , Masculino , Coelhos , Fatores de Tempo
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