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1.
Membranes (Basel) ; 13(2)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36837629

RESUMO

Silver/silver halide materials are considered as efficient and highly stable plasmonic photocatalysts for the organic pollutant degradation and hydrogen evolution from water splitting under solar irradiation, and they possess promising antibacterial activity. Ordered mesoporous silica materials including porous glasses are considered as the most promising template for silver-containing structures. In the present work, Ag/AgHal-doped (Hal = Cl, Br) vitreous membranes on a base of the mesoporous glasses were prepared via step-by-step single-stage impregnation procedure. The chemical and phase composition of the modified membranes were identified by the X-ray photoelectron spectroscopy, the X-ray diffraction and the energy-dispersive X-ray spectroscopy. The structure and morphology of inner membrane space were studied by the scanning electron microscopy. Electrokinetic properties of the silver-containing vitreous membranes were determined by the differential method and the streaming potential method. The inner membrane space is modified unevenly with appearance of the clearly defined regions with different silver content. The formation of the Ag/AgCl clusters along with the individual nanoparticles over thickness of the 1-mm membrane with mean pore radius of 23 nm was detected. The modification of the pore space by Ag-containing structures and the type of halogen ion almost do not affect the electrochemical behavior of the mesoporous vitreous membranes.

2.
J Clin Med ; 11(5)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35268481

RESUMO

Impaired glucose tolerance (IGT) is a common carbohydrate metabolism disorder world-wide. To evaluate the efficacy and safety of 12-week Subetta therapy in correcting 2-h plasma glucose in patients with IGT, a multicenter, double-blind, placebo-controlled, randomized clinical trial was performed. Derived by technological treatment of antibodies to insulin receptor ß-subunit and endothelial NO synthase, Subetta increases the sensitivity of insulin receptors by activating the insulin signaling pathway. Oral glucose tolerance test (OGTT), fasting plasma glucose (FPG), and glycated hemoglobin (HbA1c) were examined at screening, after 4 and 12 weeks. In Per Protocol population, 2-h plasma glucose in the Subetta group decreased by 2.05 ± 2.11 mmol/L (versus 0.56 ± 2.55 mmol/L in the Placebo group) after 12 weeks. The difference between the two groups was 1.49 ± 2.33 mmol/L (p < 0.0001). After 12 weeks, 65.2% of patients had 2-h plasma glucose <7.8 mmol/L. FPG remained almost unchanged. HbA1c tended to decrease. The number of adverse events did not differ in both groups. Subetta treatment is beneficial for patients with IGT; it also prevents progression of carbohydrate metabolism disorders.

3.
ACS Omega ; 7(4): 3369-3383, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35128247

RESUMO

Derivatives of natural allylpolyalkoxybenzenes conjugated to triphenylphosphonium (TPP) cations by aliphatic linkers of three, six, seven, and eight atoms were synthesized to examine the role of the polyalkoxybenzene pharmacophore, TPP fragment, and linker length in antiproliferative activities. The key synthetic procedures included (i) hydroboration-oxidation of apiol, dillapiol, myristicin, and allyltetramethoxybenzene; (ii) acylation of polyalkoxybenzyl alcohols or amines; and (iii) condensation of polyalkoxybenzaldehydes followed by hydrogenation and cyclopropyl-homoallyl rearrangement. The targeted TPP conjugates as well as the starting allylbenzenes, the corresponding alkylpolyalkoxybenzenes, and the respective alkyl-TPP salts were evaluated for cytotoxicity in a panel of human cancer cell lines using MTT and Click-iT-EdU assays and in a sea urchin embryo model. The linker of three carbon atoms was identified as favorable for selective cancer cell growth inhibition. Although the propyl-TPP salt was cytotoxic at low micromolar concentrations, the introduction of a polyalkoxybenzene moiety significantly potentiated inhibition of both cell growth and de novo DNA synthesis in several human cancer cell lines, HST-116 colon cancer, A375 melanoma, PC-3 prostate cancer, and T-47D breast carcinoma cells, while it failed to produce any developmental abnormalities in the sea urchin embryos.

4.
Int J Mol Sci ; 22(24)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34948177

RESUMO

Induction of BDNF-TrkB signaling is associated with the action mechanisms of conventional and fast-acting antidepressants. GSB-106, developed as a small dimeric dipeptide mimetic of BDNF, was previously shown to produce antidepressant-like effects in the mouse Porsolt test, tail suspension test, Nomura water wheel test, in the chronic social defeat stress model and in the inflammation-induced model of depression. In the present study, we evaluated the effect of chronic per os administration of GSB-106 to Balb/c mice under unpredictable chronic mild stress (UCMS). It was observed for the first time that long term GSB-106 treatment (1 mg/kg, 26 days) during ongoing UCMS procedure ameliorated the depressive-like behaviors in mice as indicated by the Porsolt test. In addition, chronic per os administration of GSB-106 resulted in an increase in BDNF levels, which were found to be decreased in the prefrontal cortex and hippocampus of mice after UCMS. Furthermore, prolonged GSB-106 treatment was accompanied by an increase in the content of pTrkB706/707 in the prefrontal cortex and by a pronounced increase in the level of pTrkB816 in both studied brain structures of mice subjected to UCMS procedure. In summary, the present data show that chronic GSB-106 treatment produces an antidepressant-like effect in the unpredictable chronic mild stress model, which is likely to be associated with the regulation of the BDNF-TrkB signaling.


Assuntos
Dipeptídeos/metabolismo , Dipeptídeos/farmacologia , Glicoproteínas de Membrana/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Antidepressivos/farmacologia , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Glicoproteínas de Membrana/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Proteínas Tirosina Quinases/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico
5.
Inorg Chem ; 60(21): 16286-16293, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34677932

RESUMO

We report here a detailed experimental and theoretical investigation of hexavalent uranium in various local configurations with a high-energy-resolution fluorescence-detected X-ray absorption near-edge structure at the U M4 edge. We show the pronounced sensitivity of the technique to the arrangement of atoms around the absorber and provide a detailed theoretical interpretation revealing the nature of spectral features. Calculations based on density functional theory and on crystal field multiplet theory indicate that for all local configurations analyzed, the main peak corresponds to nonbonding 5f orbitals, and the highest energy peak corresponds to antibonding 5f orbitals. Our findings agree with the accepted interpretation of uranyl spectral features and embed the latter in a broader field of view, which interprets the spectra of a large variety of U6+-containing samples on a common theoretical ground.

6.
Inorg Chem ; 59(18): 13383-13389, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32876441

RESUMO

Actinide chemistry appears to be a challenge for both experimentalists and theoreticians. Radioactivity and computational obstacles lead to a lack of heterogeneous data describing actinide compounds. Here we present a description of the first database devoted to ab initio actinide calculations. The database contains information about the structures and electronic properties of 87 actinide and 17 other compounds in the gas phase and is ready-to-use for benchmarking computational and experimental results or building new semiempirical models.

7.
Diabetes Res Clin Pract ; 142: 1-9, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29807102

RESUMO

BACKGROUND: To examine efficacy of Subetta as an add-on to insulin therapy in patients with type 1 diabetes mellitus (T1DM) a multicenter, double-blind, placebo-controlled, randomized clinical trial was performed. Derived by technological treatment of antibodies to insulin receptor ß-subunit and endothelial NO synthase Subetta was previously proved to activate insulin signaling pathway. METHODS: A total of 144 randomized patients with poor glycemic control in basal-bolus insulin regime were included in intention-to-treat analysis in Subetta add-on therapy or placebo (n = 72 in both groups). Hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), basal and prandial insulin doses, number of hypoglycemia episodes confirmed by self-monitoring of blood glucose were recorded for 36 weeks. RESULTS: The baseline characteristics of subjects did not differ between the two groups. HbA1c mean (±standard deviation) change was -0.59 ±â€¯0.99% (95% CI -0.84 to -0.37) after 36 weeks in Subetta (vs. -0.20 ±â€¯1.14%; 95% CI -0.44 to 0.11 in placebo; p = 0.028). The rate of overall hypoglycemia events was 7.9 per patient year (95% CI 7.1-8.6) in Subetta group and 7.6 (95% CI 6.9-8.4) in Placebo group (p = 0.63). The basal and total insulin doses did not change at the end of 36 weeks in both groups. CONCLUSIONS: Subetta add-on therapy boosting insulin activity and improving glycemic control in patients with T1DM is proved to be beneficial. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01868594.


Assuntos
Anticorpos/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Adulto , Anticorpos/farmacologia , Diabetes Mellitus Tipo 1/patologia , Método Duplo-Cego , Feminino , Humanos , Hipoglicemiantes/farmacologia , Masculino
8.
J Environ Radioact ; 184-185: 22-31, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29331559

RESUMO

The paper reported the experience gained in the course of decommissioning EI-2 Production Uranium-Graphite Nuclear Reactor. EI-2 was a production Uranium-Graphite Nuclear Reactor located on the Production and Demonstration Center for Uranium-Graphite Reactors JSC (PDC UGR JSC) site of Seversk City, Tomsk Region, Russia. EI-2 commenced its operation in 1958, and was shut down on December 28, 1990, having operated for the period of 33 years all together. The extra pure grade graphite for the moderator, water for the coolant, and uranium metal for the fuel were used in the reactor. During the operation nitrogen gas was passed through the graphite stack of the reactor. In the process of decommissioning the PDC UGR JSC site the cavities in the reactor space were filled with clay-based materials. A specific composite barrier material based on clays and minerals of Siberian Region was developed for the purpose. Numerical modeling demonstrated the developed clay composite would make efficient geological barriers preventing release of radionuclides into the environment.


Assuntos
Grafite , Reatores Nucleares , Resíduos Radioativos/análise , Eliminação de Resíduos/métodos , Urânio
9.
Behav Pharmacol ; 29(4): 375-378, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29076866

RESUMO

The antidepressant-like effect of fluoxetine (20 mg/kg i.p.) has been assessed using the forced swimming test (FST) in IRC (CD-1) mice exposed or not to a pretest session of different duration (5 or 20 min). The influence of the mitochondrial translocator protein (TSPO) activity on the antidepressant-like effect of fluoxetine (20 mg/kg i.p.) in the FST was also studied. The antidepressant-like effect of fluoxetine was observed only in mice subjected to a 5-min pretest session 24 h before the FST. The TSPO antagonist PK11195 [1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinolinecarboxamide; 1 or 3 mg/kg i.p.] inhibited the antidepressant activity of fluoxetine in the FST. In the present study, fluoxetine or PK11195 was administered for a short duration. We suppose that the functional activity of TSPO may depend on a pretest session and that using this procedure is necessary to detect antidepressant activity of fluoxetine-like drugs.


Assuntos
Fluoxetina/metabolismo , Fluoxetina/farmacologia , Proteína Mitocondrial Trifuncional/efeitos dos fármacos , Animais , Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Modelos Animais de Doenças , Isoquinolinas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteína Mitocondrial Trifuncional/metabolismo , Proteína Mitocondrial Trifuncional/fisiologia , Atividade Motora/efeitos dos fármacos , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Estresse Psicológico/tratamento farmacológico , Natação
10.
Photochem Photobiol ; 91(1): 59-67, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25263082

RESUMO

The mechanism of the photodegradation of azo dyes via ultrasonication is studied using a combination of the high-performance liquid chromatography and UV-vis spectroscopy with detailed analysis of the kinetics. Based on the kinetics studies of the sonodegradation, it was proposed that the degradation of azo dyes was a multistage process that involved: (1) the direct attack of azo bonds and phenyl rings of dyes by the sonochemically formed reactive oxygen species; (2) the activation of semiconductor particles by the light emitted during cavitation and the triggering of the photocatalytic pathways of dye degradation and (3) increase of the adsorption capacity of the semiconductor particles due to the sonomechanically induced interparticle collisions. The detailed kinetics study can help in following an effective process up-scaling. It was demonstrated that extremely short pulses of light flashes in a cavitated mixture activated the surface of photocatalysts and significantly enhanced dye degradation processes.

11.
Front Psychol ; 5: 863, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25147537

RESUMO

The goal of the present study was to ascertain whether children with normal hearing and prelingually deaf children with cochlear implants could use pitch or timing cues alone or in combination to identify familiar songs. Children 4-7 years of age were required to identify the theme songs of familiar TV shows in a simple task with excerpts that preserved (1) the relative pitch and timing cues of the melody but not the original instrumentation, (2) the timing cues only (rhythm, meter, and tempo), and (3) the relative pitch cues only (pitch contour and intervals). Children with normal hearing performed at high levels and comparably across the three conditions. The performance of child implant users was well above chance levels when both pitch and timing cues were available, marginally above chance with timing cues only, and at chance with pitch cues only. This is the first demonstration that children can identify familiar songs from monotonic versions-timing cues but no pitch cues-and from isochronous versions-pitch cues but no timing cues. The study also indicates that, in the context of a very simple task, young implant users readily identify songs from melodic versions that preserve pitch and timing cues.

12.
Ear Hear ; 35(1): 118-25, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24213020

RESUMO

OBJECTIVES: Although the spectrally degraded input provided by cochlear implants (CIs) is sufficient for speech perception in quiet, it poses problems for talker identification. The present study examined the ability of normally hearing (NH) children and child CI users to recognize cartoon voices while listening to spectrally degraded speech. DESIGN: In Experiment 1, 5- to 6-year-old NH children were required to identify familiar cartoon characters in a three-alternative, forced-choice task without feedback. Children heard sentence-length utterances at six levels of spectral degradation (noise-vocoded utterances with 4, 8, 12, 16, and 24 frequency bands and the original or unprocessed stimuli). In Experiment 2, child CI users 4 to 7 years of age and a control sample of 4- to 5-year-old NH children were required to identify the unprocessed stimuli from Experiment 1. RESULTS: NH children in Experiment 1 identified the voices significantly above chance levels, and they performed more accurately with increasing spectral information. Practice with stimuli that had greater spectral information facilitated performance on subsequent stimuli with lesser spectral information. In Experiment 2, child CI users successfully recognized the cartoon voices with slightly lower accuracy (0.90 proportion correct) than NH peers who listened to unprocessed utterances (0.97 proportion correct). CONCLUSIONS: The findings indicate that both NH children and child CI users can identify cartoon voices under conditions of severe spectral degradation. In such circumstances, children may rely on talker-specific phonetic detail to distinguish one talker from another.


Assuntos
Surdez/reabilitação , Reconhecimento Fisiológico de Modelo/fisiologia , Percepção da Fala/fisiologia , Voz , Estimulação Acústica/métodos , Estudos de Casos e Controles , Criança , Pré-Escolar , Implante Coclear , Implantes Cocleares , Surdez/fisiopatologia , Humanos , Espectrografia do Som
13.
Front Psychol ; 4: 351, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23801976

RESUMO

Cochlear implants have enabled many congenitally or prelingually deaf children to acquire their native language and communicate successfully on the basis of electrical rather than acoustic input. Nevertheless, degraded spectral input provided by the device reduces the ability to perceive emotion in speech. We compared the vocal imitations of 5- to 7-year-old deaf children who were highly successful bilateral implant users with those of a control sample of children who had normal hearing. First, the children imitated several happy and sad sentences produced by a child model. When adults in Experiment 1 rated the similarity of imitated to model utterances, ratings were significantly higher for the hearing children. Both hearing and deaf children produced poorer imitations of happy than sad utterances because of difficulty matching the greater pitch modulation of the happy versions. When adults in Experiment 2 rated electronically filtered versions of the utterances, which obscured the verbal content, ratings of happy and sad utterances were significantly differentiated for deaf as well as hearing children. The ratings of deaf children, however, were significantly less differentiated. Although deaf children's utterances exhibited culturally typical pitch modulation, their pitch modulation was reduced relative to that of hearing children. One practical implication is that therapeutic interventions for deaf children could expand their focus on suprasegmental aspects of speech perception and production, especially intonation patterns.

14.
Cochlear Implants Int ; 14(2): 80-91, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23453221

RESUMO

OBJECTIVES: This study examined the ability of prelingually deaf children with bilateral implants to identify emotion (i.e. happiness or sadness) in speech and music. METHODS: Participants in Experiment 1 were 14 prelingually deaf children from 5-7 years of age who had bilateral implants and 18 normally hearing children from 4-6 years of age. They judged whether linguistically neutral utterances produced by a man and woman sounded happy or sad. Participants in Experiment 2 were 14 bilateral implant users from 4-6 years of age and the same normally hearing children as in Experiment 1. They judged whether synthesized piano excerpts sounded happy or sad. RESULTS: Child implant users' accuracy of identifying happiness and sadness in speech was well above chance levels but significantly below the accuracy achieved by children with normal hearing. Similarly, their accuracy of identifying happiness and sadness in music was well above chance levels but significantly below that of children with normal hearing, who performed at ceiling. For the 12 implant users who participated in both experiments, performance on the speech task correlated significantly with performance on the music task and implant experience was correlated with performance on both tasks. DISCUSSION: Child implant users' accurate identification of emotion in speech exceeded performance in previous studies, which may be attributable to fewer response alternatives and the use of child-directed speech. Moreover, child implant users' successful identification of emotion in music indicates that the relevant cues are accessible at a relatively young age.


Assuntos
Percepção Auditiva , Implantes Cocleares , Surdez/reabilitação , Emoções , Música , Acústica da Fala , Percepção da Fala , Limiar Auditivo , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Valores de Referência , Espectrografia do Som , Testes de Discriminação da Fala
15.
J Biophotonics ; 3(5-6): 336-46, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20414903

RESUMO

This paper deals with the possibility of application of aluminum phthalocyanine (AlPc) nanoparticles in clinical practice. AlPc fluoresces in the molecular form but in the form of nanoparticles it does not. Separation of molecules from an AlPc nanoparticle and therefore the appearance of fluorescence occurs under the effect of a number of biochemo-physical factors. Owing to this feature the application of AlPc nanoparticles followed by the measurement of fluorescence spectra is proposed as a diagnostics method. It was shown that after AlPc nanoparticle application on a tooth surface the fluorescence intensity in the enamel microdamage area is 2-3 times higher than that in the normal enamel area. The appearance of fluorescence after application of AlPc nanoparticles on skin autografts testifies to the presence of inflammation.


Assuntos
Esmalte Dentário/patologia , Odontologia/métodos , Rejeição de Enxerto/diagnóstico , Indóis , Nanopartículas Metálicas , Compostos Organometálicos , Transplante de Pele , Animais , Coloides/química , Procedimentos Cirúrgicos Dermatológicos , Feminino , Fluorescência , Humanos , Técnicas In Vitro , Indóis/química , Inflamação/diagnóstico , Luz , Nanopartículas Metálicas/química , Camundongos , Compostos Organometálicos/química , Fatores de Risco , Espalhamento de Radiação , Pele/patologia , Soluções , Espectrometria de Fluorescência , Fatores de Tempo , Transplante Autólogo
16.
Dev Sci ; 9(6): 583-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17059455

RESUMO

We evaluated 6- and 7-month-olds' preference and memory for expressive recordings of sung lullabies. In Experiment 1, both age groups preferred lower-pitched to higher-pitched renditions of unfamiliar lullabies. In Experiment 2, infants were tested after 2 weeks of daily exposure to a lullaby at one pitch level. Seven-month-olds listened significantly longer to the lullaby at a novel pitch level than at the original pitch level. Six-month-olds showed no preference but their low-pitch preference was eliminated. We conclude that infants' memory for musical performances is enhanced by the ecological validity of the materials. Moreover, infants' pitch preferences are influenced by their previous exposure and by the nature of the music.


Assuntos
Desenvolvimento Infantil , Memória , Rememoração Mental , Música , Percepção da Altura Sonora , Psicologia da Criança , Humanos , Lactente , Retenção Psicológica
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