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1.
ACS Nano ; 18(20): 12589-12597, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38709673

RESUMEN

Circular polarization-resolved Raman scattering methods include Raman optical activity (ROA) and its derivative─surface-enhanced Raman optical activity (SEROA). These spectroscopic modalities are rapidly developing due to their high information content, stand-off capabilities, and rapid development of Raman-active chiral nanostructures. These methods enable a direct readout of the vibrational energy levels of chiral molecules, crystals, and nanostructured materials, making it possible to study complex interactions and the dynamic interfaces between them. They were shown to be particularly valuable for nano- and biotechnological fields encompassing complex particles with nanoscale chirality that combine strong scattering and intense polarization rotation. This perspective dives into recent advancements in ROA and SEROA, their distinction from surface-enhanced Raman scattering, and the potential of these information-rich label-free spectroscopies for the detection of chiral biomolecules.

2.
Macromol Biosci ; : e2400149, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38819531

RESUMEN

In recent years, multifunctional nanocarriers that provide simultaneous drug delivery and imaging have attracted enormous attention, especially in cancer treatment. In this research, a biocompatible fluorescent multifunctional nanocarrier is designed for the co-delivery of capsaicin (CPS) and nitrogen-doped graphene quantum dots (N-GQDs) using the pH sensitive amphiphilic block copolymer (poly(2-ethyl-2-oxazoline)-b-poly(ε-caprolactone), PEtOx-b-PCL). The effects of the critical formulation parameters (the amount of copolymer, the concentration of poly(vinyl alcohol) (PVA) as a stabilizing agent in the inner aqueous phase, and volume of the inner phase) are evaluated to achieve optimal nanoparticle (NP) properties using Central Composite Design. The optimized NPs demonstrated a desirable size distribution (167.8 ± 1.4 nm) with a negative surface charge (-19.9 ± 0.4) and a suitable loading capacity for CPS (70.80 ± 0.05%). The CPS & N-GQD NPs are found to have remarkable toxicity on human breast adenocarcinoma cell line (MCF-7). The solid fluorescent signal is acquired from cells containing multifunctional NPs, according to the confocal microscope imaging results, confirming the significant cellular uptake. This research illustrates the enormous potential for cellular imaging and enhanced cancer therapy offered by multifunctional nanocarriers that combine drug substances with the novel fluorescent agents.

3.
Int. arch. otorhinolaryngol. (Impr.) ; 26(3): 440-445, July-Sept. 2022. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1405125

RESUMEN

Abstract Introduction Childhood and adolescent obesity is associated with insulin resistance, abnormal glucose metabolism, hypertension, dyslipidemia, inflammation, liver disease, and compromised vascular function. Objective We aimed to evaluate the effects of obesity on the auditory function and speech audiometry of children and adolescents. Methods Subjects with a body mass index (BMI) higher than +2 standard deviation (SD) were classified as obese, and subjects with normal BMI SD were classified as the control group. Blood samples were taken for glucose, insulin, and lipid profiles following an 8-hour fasting period, and a hepatobiliary ultrasound was performed. The homeostatic model assessment for insulin resistance (HOMA-IR) was calculated. The audiological evaluation included pure-tone audiometry (PTA), speech reception threshold (SRT), and speech discrimination score (SDS). Results The study included 100 children (50 girls) with obesity, with a mean age of 11.4 ± 2.9 years and 30 children with normal body weight, with a mean age of 11.9 ± 3.3 years. Of the children with obesity, 55% (n = 55) were found to have hyperlipidemia, 68% (n = 68) insulin resistance, and 21% (n = 21) hepatosteatosis. There were no statistically significant differences between children with obesity and the control group in terms of SDS or PTA, while SRT was found to be higher in children with obesity. There was no difference between obese children with or without hyperlipidemia, between obese children with or without insulin resistance, and between obese children with or without hepatosteatosis, according to hearing tests. Conclusion The result of the present study indicates that children with obesity are more prone to having auditory problems than the normal population. We recommend more frequent audiological evaluations, including speech audiometry, in children and adolescents with obesity problems

4.
ACS Appl Mater Interfaces ; 13(7): 8823-8831, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33583183

RESUMEN

The detection of cancer biomarkers at an early stage of tumor development is vital for effective diagnosis and treatment of cancer. Current diagnostic tools can often detect cancer only when the biomarker levels are already too high, so that the tumors have spread and treatments are less effective. It is urgent therefore to develop highly sensitive assays for the detection of such biomarkers at the lowest possible concentration. In this context, we developed a sandwich immunoassay based on surface-enhanced Raman scattering (SERS) for the ultrasensitive detection of α-fetoprotein (AFP), which is typically present in human serum as a biomarker indicative of early stages of hepatocellular carcinoma. In the immunoassay design, molybdenum disulfide (MoS2) modified with a monoclonal antibody was used as a capture probe for AFP. A secondary antibody linked to an SERS-encoded nanoparticle was employed as the Raman signal reporter, that is, the transducer for AFP detection. The sandwich immunocomplex "capture probe/target/SERS tag" was deposited on a silicon wafer and decorated with silver-coated gold nanocubes to increase the density of "hot spots" on the surface of the immunosensor. The developed SERS immunosensor exhibits a wide linear detection range (1 pg mL-1 to 10 ng mL-1) with a limit of detection as low as 0.03 pg mL-1 toward AFP with good reproducibility (RSD < 6%) and stability. These parameters demonstrate that the proposed immunosensor has the potential to be used as an analytical platform for the detection of early-stage cancer biomarkers in clinical applications.


Asunto(s)
Disulfuros/química , Oro/química , Inmunoensayo , Nanopartículas del Metal/química , Molibdeno/química , Plata/química , alfa-Fetoproteínas/análisis , Humanos , Tamaño de la Partícula , Espectrometría Raman , Propiedades de Superficie
5.
Mikrochim Acta ; 187(4): 223, 2020 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-32166596

RESUMEN

An innovative and portable design to fabricate an electrochemical sensor based on metallic phase MoS2 (1T-MoS2) decorated with shape-dependent gold nanostructures for the determination of doxorubicin (DOX) is presented. In this context, homogenous and uniform single-crystal gold nanospheres (AuNSPs) and nanorods (AuNRDs) were firstly synthesized by seeded growth approach. Afterwards, AuNSPs and AuNRDs were anchored on 1T-MoS2 surfaces to construct the desired electrochemical sensing platform towards the DOX assay. 1T-MoS2 was exfoliated by metal intercalation process using NaK metal alloys. The structure and surface morphology of 1T-MoS2, AuNSPs, and AuNRDs were characterized by XPS, Raman, UV-vis, TEM, and SEM. The electrochemical behavior of DOX using various MoS2-based electrochemical sensors prepared on screen-printed electrode (SPE) was examined by cyclic voltammetry and adsorptive stripping differential pulse voltammetry. The electrocatalytic efficiency of AuNRDs on 1T-MoS2 was also compared with that of AuNSPs on 1T-MoS2, and it showed much better electrocatalytic activity towards the DOX. A nanocomposite prepared with AuNRDs and 1T-MoS2 on SPE (AuNRDs/1T-MoS2/SPE) exhibited a linear relationship between peak current and DOX concentration in the range 0.01-9.5 µM with a detection limit of 2.5 nM. The AuNRDs/1T-MoS2/SPE was successfully applied to the sensitive and rapid determination of DOX in spiked human serum samples with satisfactory recoveries in the range 99.2-100.8%. Graphical abstract Schematic representation of a portable design for electrochemical sensor based on shape-controlled gold nanostructures decorated on metallic phase molybdenum disulfide (1T-MoS2) towards the sensitive determination of doxorubicin.


Asunto(s)
Antibióticos Antineoplásicos/análisis , Técnicas Biosensibles , Disulfuros/química , Doxorrubicina/análisis , Técnicas Electroquímicas , Oro/química , Molibdeno/química , Nanoestructuras/química , Humanos
6.
Braz. j. otorhinolaryngol. (Impr.) ; 84(4): 426-434, July-Aug. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951848

RESUMEN

Abstract Introduction The first and one of the most important steps in facial plastic surgery is accurate preoperative facial analysis and recording of data that may help the surgeon to check the outcomes of his/her techniques, promoting a surgeon's professional development. Objective To evaluate the esthetic outcomes of external septorhinoplasty relevant to ethnic facial harmony and to investigate the relationship of the columellar incision scar with the type of skin and columellar incision type in a Turkish population. Methods In total, 28 consecutive adult male patients with a mean age of 32.14 ± 10.66 years (range: 18-61 years) were included the study. Primary outcomes were preoperative and postoperative photogrammetric facial analyses of the patients including measurement of nasofrontal angle, nasolabial angle and nasal projection ratios (Gode) assessed according to the data derived from the Rhinobase program. Results were compared to facial proportions of the Turkish population. Columellar incision scar scores related to the Fitzpatrick skin type classification of the patients and columellar incision types used for the external approach were secondary outcomes of the study. Results Mean preoperative and postoperative nasofrontal angles were 148.04° ± 8.18° and 144.50° ± 7.15°, respectively, while mean preoperative and postoperative nasolabial angles were 87.59° ± 14.01° and 98.50° ± 9.71°, respectively. Mean preoperative and postoperative nasal tip projection ratios were 0.56 ± 0.05 and 0.60 ± 0.06, respectively. The differences between pre- and postoperative measurements were all significantly different and were in accordance with Turkish nasal harmony. Columellar inverted "V" incisions were performed in 15 (53.6%) patients while "V" incisions were used in 13 (46.4%) patients. Fitzpatrick skin Type 4 was seen in 46.42% of the patients, Fitzpatrick Type 3 in 46.42% and Fitzpatrick Type 2 in 7.14% of the patients. No significant difference was seen between columellar scar scores according to skin type and columellar incision type used for external septorhinoplasty. Conclusions This study demonstrated that outcomes for nasofrontal angle, nasolabial angle and nasal tip projection ratios analyzed using the Rhinobase program in patients who underwent external septorhinoplasty were similar to reference values for the Turkish population.


Resumo Introdução O primeiro e um dos mais importantes passos na cirurgia plástica facial é a análise pré-operatória facial precisa e o registro de dados que podem ajudar o cirurgião a verificar os resultados de suas técnicas, promovendo seu desenvolvimento profissional. Objetivo Avaliar os resultados estéticos da rinosseptoplastia externa relevantes para a harmonia étnica facial e investigar a associação da cicatriz de incisão columelar com o tipo de pele e o tipo de incisão columelar em uma população turca. Método No total, 28 pacientes adultos consecutivos com média de idade de 32,14 ± 10,66 anos (intervalo: 18-61 anos) foram incluídos no estudo. Os desfechos primários foram as análises faciais fotogramétricas pré-operatórias e pós-operatórias dos pacientes, incluindo a medida do ângulo nasofrontal, ângulo nasolabial e razões da projeção nasal (Gode), avaliados de acordo com os dados derivados do programa Rhinobase. Os resultados foram comparados às proporções faciais da população turca. Os escores de cicatriz de incisão columelar relacionados com a classificação de Fitzpatrick do tipo de pele dos pacientes e os tipos de incisão columelar usados para a abordagem externa foram os desfechos secundários do estudo. Resultados Os ângulos nasofrontais pré- e pós-operatórios médios foram 148,04 ± 8,18° e 144,50 ± 7,15°, respectivamente, enquanto os ângulos nasolabiais pré- e pós-operatórios médios foram 87,59 ± 14,01° e 98,50 ± 9,71°, respectivamente. As razões médias da projeção nasal pré- e pós-operatória foram de 0,56 ± 0,05 e 0,60 ± 0,06, respectivamente. As diferenças entre as medidas pré- e pós-operatórias foram todas significativamente diferentes e estavam de acordo com a harmonia nasal turca. A incisão columelar em "V" invertido foi utilizada em 15 (53,6%) pacientes e a incisão em "V" foi utilizada em 13 (46,4%) pacientes. Pele Fitzpatrick tipo 4 foi observada em 46,42% dos pacientes, Fitzpatrick tipo 3 em 46,42% e Fitzpatrick tipo 2 em 7,14% dos pacientes. Não foi observada diferença significativa entre os escores de cicatriz columelar de acordo com o tipo de pele e o tipo de incisão columelar utilizados na rinosseptoplastia externa. Conclusões Este estudo demonstrou que os desfechos para ângulo nasofrontal, ângulo nasolabial e razões de projeção nasal analisados pelo programa Rhinobase em pacientes submetidos à rinosseptoplastia externa foram semelhantes aos valores de referência para a população turca.


Asunto(s)
Humanos , Masculino , Adolescente , Adulto , Persona de Mediana Edad , Adulto Joven , Rinoplastia/métodos , Tabique Nasal/cirugía , Turquía , Estudios Prospectivos , Reproducibilidad de los Resultados , Estudios de Seguimiento , Cicatriz , Resultado del Tratamiento , Cara/cirugía , Puntos Anatómicos de Referencia , Procedimientos Quirúrgicos Dermatologicos
7.
Acta cir. bras ; 32(4): 280-286, Apr. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-837700

RESUMEN

Abstract Purpose: To evaluate the effect of inactive form of platelet rich plasma (PRP) on the flap viability. Methods: Thirty six rats were used. Rats were divided into six groups then 9x3 cm random pattern skin flaps were elevated from dorsum of all rats. For precluding vascularization from the base, a silicone layer was placed under the flap in groups 2(only flap+silicone), 4(saline+silicone) and 6(PRP+silicone). In groups 1(only flap), 2(only flap+silicone) nothing was done except flap surgery. In groups 3(saline) and 4(saline+silicone), saline was applied intradermally , in groups 5(PRP) and 6(PRP+silicone), inactive form of PRP which obtained from different 16 rats was applied intradermally, into certain points of flaps immediately after surgery. After 7 days flap necrosis ratio was measured in all groups. Results: Mean necrosis rate in group 5(PRP) (16.05%) was statistically significantly lower than group 1(only flap) (31,93%) and group 3(saline) (30,43%) (p<0.001). Mean necrosis rate in group 6(PRP+silicone) (36.37%) was statistically significantly lower than group 2(only flap+silicone) (47.93%) and group 4(saline+silicone) (45.65%) (p<0.001). Conclusion: Intradermal inactive platelet rich plasma administration decreases flap necrosis so for skin application.


Asunto(s)
Animales , Femenino , Ratas , Colgajos Quirúrgicos , Inyecciones Intradérmicas/métodos , Plasma Rico en Plaquetas , Supervivencia de Injerto , Colgajos Quirúrgicos/patología , Trasplante de Piel , Ratas Sprague-Dawley , Modelos Animales de Enfermedad , Necrosis/prevención & control
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