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1.
Materials (Basel) ; 17(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38255483

RESUMO

The Ce0.5Y0.35Tb0.15F3 nanoparticles with a CeF3 hexagonal structure were synthesized using the co-precipitation technique. The average nanoparticle diameter was 14 ± 1 nm. The luminescence decay curves of the Ce0.5Y0.35Tb0.15F3 nanoparticles (λem = 541 nm, 5D4-7F5 transition of Tb3+) conjugated with Radachlorin using polyvinylpyrrolidone coating as well as without Radachlorin were detected. Efficient nonradiative energy transfer from Tb3+ to the Radachlorin was demonstrated. The maximum energy transfer coefficients for the nanoparticles conjugated with Radachlorin via polyvinylpyrrolidone and without the coating were 82% and 55%, respectively. The average distance between the nanoparticle surface and Radachlorin was R0 = 4.5 nm. The best results for X-ray-induced cytotoxicity were observed for the NP-PVP-Rch sample at the lowest Rch concentration. In particular, after X-ray irradiation, the survival of A549 human lung carcinoma cells decreased by ~12%.

2.
Wiad Lek ; 75(5 pt 2): 1342-1346, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35758456

RESUMO

OBJECTIVE: The aim: To identify clinical and immunological features of acute rotavirus gastroenteritis occurring against the background of Epstein-Barr virus infection. PATIENTS AND METHODS: Materials and methods: The study involved examination of 56 children. Of them, 33 children (1 group) did not have a background infection and 23 patients (2 group) suffered from rotavirus infection on the background of the latent form of Epstein-Barr virus infection. Children in these groups were compared by gender, age, severity of the disease and other parameters. Quantitative data were presented as mean and standard deviation (M±SD). Differences at p <0.05 were considered statistically significant. RESULTS: Results: The data suggest that the presence of background Epstein-Barr virus in children with rotavirus infection leads to later hospitalization, lower temperature response rates, lower frequency of vomiting at the onset of the disease, and longer duration of fever and diarrhea. At the same time, in children infected with Epstein-Barr virus, the relative content of CD8+ T lymphocytes dominated both in the acute period of the disease and in the period of convalescence against the background of reduced relative content of CD16+, CD22+ T lymphocytes and IgM in the period of early convalescence. CONCLUSION: Conclusions: The study allowed to reveal the influence of latent EBV infection on the clinical and immunological parameters of rotavirus gastroenteritis.


Assuntos
Infecções por Vírus Epstein-Barr , Gastroenterite , Infecções por Rotavirus , Criança , Convalescença , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/diagnóstico , Gastroenterite/complicações , Herpesvirus Humano 4 , Humanos , Infecções por Rotavirus/complicações
3.
ACS Appl Mater Interfaces ; 13(46): 54874-54883, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34723477

RESUMO

Lanthanide-based upconversion (UC) allows harvesting sub-bandgap near-infrared photons in photovoltaics. In this work, we investigate UC in perovskite solar cells by implementing UC single crystal BaF2:Yb3+, Er3+ at the rear of the solar cell. Upon illumination with high-intensity sub-bandgap photons at 980 nm, the BaF2:Yb3+, Er3+ crystal emits upconverted photons in the spectral range between 520 and 700 nm. When tested under terrestrial sunlight representing one sun above the perovskite's bandgap and sub-bandgap illumination at 980 nm, upconverted photons contribute a 0.38 mA/cm2 enhancement in the short-circuit current density at lower intensity. The current enhancement scales non-linearly with the incident intensity of sub-bandgap illumination, and at higher intensity, 2.09 mA/cm2 enhancement in current was observed. Hence, our study shows that using a fluoride single crystal like BaF2:Yb3+, Er3+ for UC is a suitable method to extend the response of perovskite solar cells to near-infrared illumination at 980 nm with a subsequent enhancement in current for very high incident intensity.

4.
IUBMB Life ; 73(5): 726-738, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33686787

RESUMO

The importance of the tumor microenvironment in cancer progression has been well studied for many years. Immune checkpoint inhibitors (ICIs) are regarded as potential strategies in enhancing the immune responses in patients with cancer, particularly colorectal cancer (CRC). Notably, CRCs are extraordinarily heterogeneous and mostly are microsatellite-stable (MSS) or cold tumors, which means that the immune response is not usually as strong as that of foreign cells. T-cell immunoglobulin and ITIM domain (TIGIT) is a new immune checkpoint receptor overexpressed inside the CRC tumor-immune microenvironments. Moreover, several studies have shown that TIGIT in combination with other ICIs and/or conventional treatments, can lead to a robust anti-tumor response in CRC. This review looks deep inside TIGIT expression patterns, their various functions, and possible immunotherapy strategies to increase survival rates and decrease immune-related adverse events.


Assuntos
Adenocarcinoma/terapia , Neoplasias Colorretais/terapia , Inibidores de Checkpoint Imunológico , Proteínas de Checkpoint Imunológico/imunologia , Imunoterapia/métodos , Receptores Imunológicos/antagonistas & inibidores , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Motivos de Aminoácidos , Animais , Antígenos CD/imunologia , Sistemas CRISPR-Cas , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/radioterapia , Terapia Combinada , Microbioma Gastrointestinal , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Prognóstico , Domínios Proteicos , Receptores Imunológicos/biossíntese , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Microambiente Tumoral
5.
Carbohydr Polym ; 250: 116866, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33049816

RESUMO

Hydrophobic up-conversion nanocomposite films have been developed based on TEMPO-oxidized cellulose nanofibrils (TOCNF) modified with alkyl ketene dimer (AKD) as a matrix and MF2:Ho (M = Ca, Sr) as a phosphor. Fabrication of homogeneous, strong and translucent TOCNF/MF2:Ho-AKD films with water contact angle of 123 ±â€¯2° was accomplished with mild drying at 110 °C. These hydrophobic nanocomposite films demonstrated stable up-conversion luminescence in the visible spectral range upon excitation of the 5I7 level of Ho3+ ions by laser irradiation at 1912 nm both under ambient conditions and in a humid atmosphere (92 ±â€¯2% humidity). The absence of luminescence quenching in a high humidity atmosphere for TOCNF/MF2:Ho-AKD composite films was considered to be due to the reliable shielding effect of the hydrophobic TOCNF-AKD matrix. The films show promise for visualizing 2 µm laser radiation in medicine and monitoring of the atmosphere.


Assuntos
Ácidos Carboxílicos/química , Celulose/química , Etilenos/química , Fluoretos/química , Cetonas/química , Nanocompostos/química , Fosfatos/química , Polímeros/química , Interações Hidrofóbicas e Hidrofílicas
6.
Opt Lett ; 45(13): 3435-3438, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32630864

RESUMO

Measurements of the refractive indices and the full set of longitudinal acousto-optical figures of merit in an orthorhombic single-crystal indium iodide (InI) were carried out. The high acousto-optic characteristics (M2 up to 1100×10-15s3kg-1) and strong optical anisotropy (Δn=0.47) make it possible to design various types of high-performance acousto-optic devices of the middle and far-infrared spectral range. In combination with a wide transparency range (0.62-51µm), the obtained characteristics make the crystal extremely promising in comparison with most existing analogs.

7.
J Appl Toxicol ; 27(6): 538-50, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17351914

RESUMO

A study was conducted of acute intoxication of infant and adult Wistar rats with fluoroacetamide (FAA), an inhibitor of oxidative metabolism. FAA was administered orally to adult rats at 1/2 LD(50) and subcutaneously to infant rats at LD(100) or 1/10 LD(50). Electrocardiogram (ECG), respiration and motor activity were registered for 7 days. Clinical analysis of ECG and the heart rate variability (HRV) was carried out to assess the state of the vegetative nervous system. In adult rats, FAA caused marked disturbances in the activity of cardiovascular and respiratory systems, including the development of a potentially lethal acute cor pulmonale. Conversely, there were no significant changes of cardiac function and respiration in infant rats; they died because of extreme emaciation accompanied by retardation of development. In adult rats, bursts of associated cardiac and respiratory tachyarrhythmia, as well as regular high amplitude spasmodic sighs having a deca-second rhythm were observed. In both infant and adult rats, FAA caused short-term enhancement of humoral (metabolic) and sympathetic activities, followed by a gradual and stable predominance of parasympathetic influence on HRV. Under conditions of FAA inhibition of the tricarboxylic acid cycle, the observed physiological reactions may be explained by activation of alternative metabolic pathways. This is also supported by a lack of ontogenetically caused inhibition of spontaneous motor activity in infant rats poisoned with FAA, which highlights the significance of the alternative metabolic pathways for implementation of deca-second and minute rhythms and a lack of a rigid dependence of these rhythms upon activity of neuronal networks.


Assuntos
Envelhecimento , Inibidores Enzimáticos/toxicidade , Fluoracetatos/toxicidade , Frequência Cardíaca/efeitos dos fármacos , Coração/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Respiração/efeitos dos fármacos , Doença Aguda , Administração Oral , Fatores Etários , Animais , Animais Recém-Nascidos , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/fisiopatologia , Relação Dose-Resposta a Droga , Eletrocardiografia , Metabolismo Energético/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Fluoracetatos/administração & dosagem , Coração/inervação , Injeções Subcutâneas , Sistema Nervoso Parassimpático/efeitos dos fármacos , Sistema Nervoso Parassimpático/fisiopatologia , Doença Cardiopulmonar/induzido quimicamente , Doença Cardiopulmonar/fisiopatologia , Ratos , Ratos Wistar , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Fatores de Tempo , Testes de Toxicidade Aguda
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