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1.
Soc Psychiatry Psychiatr Epidemiol ; 58(6): 919-929, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36526939

RESUMO

PURPOSE: The aim of this study is to evaluate the prevalence of anxiety disorders, its correlation with sociodemographic characteristics, its comorbidities with other psychiatric disorders and its predictors in school-aged children. METHODS: This study is part of a representative, multi-centered national study that is planned by the Turkish Association of Child and Adolescent Mental Health to evaluate the prevalence of psychopathology among elementary school students in Turkey between the years 2014-2015. Children are screened via Kiddie Schedule for Affective Disorders and Schizophrenia for School Age Children Present and Lifetime Version. Impairment is assessed by a 3-point Likert type scale independently by the parent and the teacher. The final sample included 5842 children with the mean age of 8.7 years. RESULTS: The prevalence of any anxiety disorder without considering impairment is 16.7% and considering impairment is 5.2% in children according to our study. We found significant differences for comorbid Attention Deficit Hyperactivity Disorder, Disruptive Behavior Disorder, Mood Disorders, Tic Disorders, Obsessive Compulsive Disorder, Enuresis Nocturna, Encopresis, and Intellectual Disability. Having a history of paternal physical disorder, living in the regions of Marmara, Mediterranean and Black Sea were found to be the main predictors of having childhood anxiety disorders according to the logistic regression analysis. CONCLUSION: Better understanding of childhood anxiety disorders, comorbid conditions and predictors will result in earlier diagnosis and more appropriate treatment.


Assuntos
Transtornos de Ansiedade , Transtorno do Deficit de Atenção com Hiperatividade , Criança , Adolescente , Humanos , Prevalência , Turquia/epidemiologia , Transtornos de Ansiedade/psicologia , Transtornos do Humor/epidemiologia , Comorbidade , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Estudos Epidemiológicos
2.
J Synchrotron Radiat ; 27(Pt 3): 827-835, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32381787

RESUMO

Inelastic X-ray scattering is a powerful and versatile technique for studying lattice dynamics in materials of scientific and technological importance. In this article, the design and capabilities of the momentum-resolved high-energy-resolution inelastic X-ray spectrometer (HERIX) at beamline 30-ID of the Advanced Photon Source are reported. The instrument operates at 23.724 keV and has an energy resolution of 1.3-1.7 meV. It can accommodate momentum transfers of up to 72  nm-1, at a typical X-ray flux of 4.5 × 109 photons s-1 meV-1 at the sample. A suite of in situ sample environments are provided, including high pressure, static magnetic fields and uniaxial strains, all at high or cryogenic temperatures.

3.
Phys Rev Lett ; 124(23): 236401, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32603171

RESUMO

The electron-phonon interaction (EPI) is instrumental in a wide variety of phenomena in solid-state physics, such as electrical resistivity in metals, carrier mobility, optical transition, and polaron effects in semiconductors, lifetime of hot carriers, transition temperature in BCS superconductors, and even spin relaxation in diamond nitrogen-vacancy centers for quantum information processing. However, due to the weak EPI strength, most phenomena have focused on electronic properties rather than on phonon properties. One prominent exception is the Kohn anomaly, where phonon softening can emerge when the phonon wave vector nests the Fermi surface of metals. Here we report a new class of Kohn anomaly in a topological Weyl semimetal (WSM), predicted by field-theoretical calculations, and experimentally observed through inelastic x-ray and neutron scattering on WSM tantalum phosphide. Compared to the conventional Kohn anomaly, the Fermi surface in a WSM exhibits multiple topological singularities of Weyl nodes, leading to a distinct nesting condition with chiral selection, a power-law divergence, and non-negligible dynamical effects. Our work brings the concept of the Kohn anomaly into WSMs and sheds light on elucidating the EPI mechanism in emergent topological materials.

4.
Angew Chem Int Ed Engl ; 59(50): 22667-22674, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-32833290

RESUMO

Operando nuclear resonant inelastic X-ray scattering (NRIXS) and X-ray absorption fine-structure spectroscopy (XAFS) measurements were used to gain insight into the structure and surface composition of FeCu and FeAg nanoparticles (NPs) during the electrochemical CO2 reduction (CO2 RR) and to extract correlations with their catalytic activity and selectivity. The formation of a core-shell structure during CO2 RR for FeAg NPs was inferred from the analysis of the operando NRIXS data (phonon density of states, PDOS) and XAFS measurements. Electrochemical analysis of the FeAg NPs revealed a faradaic selectivity of 36 % for CO in 0.1 M KHCO3 at -1.1 V vs. RHE, similar to that of pure Ag NPs. In contrast, a predominant selectivity towards H2 evolution is obtained in the case of the FeCu NPs, analogous to the results obtained for pure Fe NPs, although small Cu NPs have also been shown to favor H2 production.

5.
J Theor Biol ; 419: 227-237, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28163008

RESUMO

We envision the molecular evolution process as an information transfer process and provide a quantitative measure for information preservation in terms of the channel capacity according to the channel coding theorem of Shannon. We calculate Information capacities of DNA on the nucleotide (for non-coding DNA) and the amino acid (for coding DNA) level using various substitution models. We extend our results on coding DNA to a discussion about the optimality of the natural codon-amino acid code. We provide the results of an adaptive search algorithm in the code domain and demonstrate the existence of a large number of genetic codes with higher information capacity. Our results support the hypothesis of an ancient extension from a 2-nucleotide codon to the current 3-nucleotide codon code to encode the various amino acids.


Assuntos
Algoritmos , Códon/genética , Código Genético/genética , Modelos Genéticos , Aminoácidos/genética , Sequência de Bases , Evolução Molecular
6.
Niger J Clin Pract ; 20(7): 822-831, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28791976

RESUMO

BACKGROUND: Recently, manufacturers have introduced bulk-fill composite resins that reportedly can be placed in increments of 4 mm or greater. OBJECTIVE: The purpose of this article was to report the results of 12 months prospective randomized clinical trial that evaluated the clinical performance of one high-viscosity bulk-fill composite resin in Class II cavities of posterior teeth. MATERIALS AND METHODS: Thirty-four participantshad at least two Class II cavities included the study. Class II cavities restored with either a Tetric EvoCeram bulk-fi fill or universal nano-hybrid resin composite (Tetric EvoCeram). A total of 74 restorations (37 with each material) on 34 patients were placed according to the manufacturers' instructions by one calibrated operator. RESULTS: Seventy restorations were evaluated after 12 months evaluation period. No postoperative sensitivity, anatomic form, retention, and secondary caries were observed after 6 and 12 months. Regarding the items color match, marginal discoloration, and marginal adaptation, the statistical analysis did not detect any statistical significance between two materials (P > 0.05). CONCLUSION: After 12 months of clinical service, all restorations evaluated for both materials were classified as ideal, receiving predominantly Alfa scores for all parameters analyzed. CLINICAL RELEVANCE: This study presents that high-viscosity bulk-fill resin composites (RCs) perform just as well as nano-hybrid RCs with the 2 mm RC layering technique, therefore could be alternative to conventional nano-hybrid RCs.


Assuntos
Resinas Compostas/uso terapêutico , Cárie Dentária/terapia , Restauração Dentária Permanente/métodos , Adulto , Cor , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nanoestruturas , Estudos Prospectivos , Viscosidade , Adulto Jovem
7.
Angew Chem Int Ed Engl ; 55(47): 14575-14579, 2016 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-27778474

RESUMO

The reaction of protein-bound iron-sulfur (Fe-S) clusters with nitric oxide (NO) plays key roles in NO-mediated toxicity and signaling. Elucidation of the mechanism of the reaction of NO with DNA regulatory proteins that contain Fe-S clusters has been hampered by a lack of information about the nature of the iron-nitrosyl products formed. Herein, we report nuclear resonance vibrational spectroscopy (NRVS) and density functional theory (DFT) calculations that identify NO reaction products in WhiD and NsrR, regulatory proteins that use a [4Fe-4S] cluster to sense NO. This work reveals that nitrosylation yields multiple products structurally related to Roussin's Red Ester (RRE, [Fe2 (NO)4 (Cys)2 ]) and Roussin's Black Salt (RBS, [Fe4 (NO)7 S3 ]. In the latter case, the absence of 32 S/34 S shifts in the Fe-S region of the NRVS spectra suggest that a new species, Roussin's Black Ester (RBE), may be formed, in which one or more of the sulfide ligands is replaced by Cys thiolates.


Assuntos
Proteínas Ferro-Enxofre/metabolismo , Ferro/metabolismo , Óxido Nítrico/metabolismo , Óxidos de Nitrogênio/metabolismo , Compostos Nitrosos/metabolismo , Ferro/química , Proteínas Ferro-Enxofre/química , Conformação Molecular , Óxido Nítrico/química , Óxidos de Nitrogênio/química , Teoria Quântica
8.
Herz ; 40(1): 123-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24154884

RESUMO

BACKGROUND: Left ventricular (LV) torsion is a sensitive indicator of myocardial contractility and cardiac structure, and has recently been recognized as a sensitive indicator of cardiac performance. The aim of our study was to assess the effect of isolated mitral stenosis on LV torsion. PATIENTS AND METHODS: We enrolled 19 patients with isolated mitral stenosis and 19 age- and gender-matched healthy subjects in the study. All patients had a normal sinus rhythm. All study subjects underwent two-dimensional echocardiography. Basal and apical LV rotations and LV torsion were evaluated using speckle-tracking echocardiography. RESULTS: Demographic characteristics, basic echocardiographic measures of LV ejection fraction, LV wall thickness, and LV mass index were similar between the two groups. The degrees of LV torsion (11.3 ± 4.7, 15.4 ± 4.9°, p=0.014) and LV basal rotation (- 3.7 ± 1.9, - 6.5 ± 2.1°, p< 0.001) were significantly decreased in the mitral stenosis group. There was a moderate positive correlation between mitral valve area and LV torsion (r=0.531, p=0.019). CONCLUSION: We showed significant reductions in LV torsion and LV basal rotation in patients with mitral valve stenosis. Structural and anatomical changes occurring during the progression of mitral stenosis may be responsible for these impaired movements.


Assuntos
Ecocardiografia/métodos , Ventrículos do Coração/anormalidades , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/diagnóstico por imagem , Anormalidade Torcional/diagnóstico por imagem , Anormalidade Torcional/etiologia , Adulto , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia
9.
Niger J Clin Pract ; 18(4): 506-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25966723

RESUMO

OBJECTIVE: This study evaluated the short-term clinical benefits of two systemic antibiotic regimes added to the nonsurgical periodontal treatment of generalized aggressive periodontitis. MATERIALS AND METHODS: The patient records were reviewed and 45 patients were selected and divided into the following three groups: Scaling and root planning (SRP) only; SRP plus azithromycin (AZT group); and SRP plus metronidazole and amoxicillin (M+A group). The periodontal indexes were recorded at baseline and 3-month posttherapy. RESULTS: The periodontal parameters were improved in all groups 3-month posttherapy. The scores were decreased more in the AZT and M+A groups than the controls, but this difference did not reach significance. In addition, the decrease in the plaque index from baseline to 3-month in the AZT group was not significant. CONCLUSION: Nonsurgical therapy reduces the probing depth, clinical attachment level, and clinical inflammation findings. This healing tendency was observed in the AZT group despite the baseline plaque scores. Therefore, AZT might be active against the bacteria in dental biofilms.


Assuntos
Periodontite Agressiva/tratamento farmacológico , Amoxicilina/administração & dosagem , Azitromicina/administração & dosagem , Metronidazol/administração & dosagem , Administração Oral , Adulto , Periodontite Agressiva/diagnóstico , Antibacterianos/administração & dosagem , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Índice de Gravidade de Doença , Resultado do Tratamento
10.
ScientificWorldJournal ; 2014: 518608, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24511287

RESUMO

This paper describes the results of a model updating study conducted on a historical aqueduct, called Veziragasi, in Turkey. The output-only modal identification results obtained from ambient vibration measurements of the structure were used to update a finite element model of the structure. For the purposes of developing a solid model of the structure, the dimensions of the structure, defects, and material degradations in the structure were determined in detail by making a measurement survey. For evaluation of the material properties of the structure, nondestructive and destructive testing methods were applied. The modal analysis of the structure was calculated by FEM. Then, a nondestructive dynamic test as well as operational modal analysis was carried out and dynamic properties were extracted. The natural frequencies and corresponding mode shapes were determined from both theoretical and experimental modal analyses and compared with each other. A good harmony was attained between mode shapes, but there were some differences between natural frequencies. The sources of the differences were introduced and the FEM model was updated by changing material parameters and boundary conditions. Finally, the real analytical model of the aqueduct was put forward and the results were discussed.


Assuntos
Materiais de Construção , Arquitetura de Instituições de Saúde , Teste de Materiais , Modelos Teóricos , Turquia
11.
Pharmacopsychiatry ; 45(1): 13-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21993869

RESUMO

OBJECTIVE: The aim of this study was to determine the eff ectiveness and safety of aripiprazole in children and adolescents with both attention deficit/hyperactivity disorder (ADHD) and conduct disorder (CD). METHODS: 20 children and adolescents, ranging in age from 6­16 years, participated in a singlecenter, open-label study (19 to completion). We began treating patients with 2.5 mg of aripiprazole in an open-label fashion for 8 weeks. Outcome measures included the Turgay DSM-IVbased child and adolescent behavior disorders screening and rating scale (T-DSM-IV), the clinical global impressions-severity and improvement scales (CGI-S and CGI-I), the child behavior checklist (CBCL), the teachers report form (TRF) and the extrapyramidal symptom rating scale (ESRS), along with laboratory assessments. RESULTS: The mean daily dosage of aripiprazole at the end of 8 weeks was 8.55 mg (SD = 1.73), with a maximum dosage of 10 mg. Based on the global improvement subscale of the CGI, we classified 12 of 19 patients (63.1 %) as responders (very much or much improved). We observed significant improvements after aripiprazole treatment with regard to inattention, hyperactivity/impulsivity, ODD, and CD subscales of the T-DSMIV (parent, teacher and clinician forms). We also observed significant improvements on many of the CBCL and TRF subscales (e. g., attention problems as well as delinquent and aggressive behavior). The participants tolerated aripiprazole, and no patient was excluded from the study because of adverse drug events. CONCLUSION: Aripiprazole is an eff ective and well-tolerated treatment for ADHD and CD symptoms; however, additional studies (specifically, placebo-controlled and double-blind studies) are needed to better defi ne the clinical use of aripiprazole in children and adolescents with ADHD-CD.


Assuntos
Antipsicóticos/uso terapêutico , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/tratamento farmacológico , Agonistas de Dopamina/uso terapêutico , Piperazinas/uso terapêutico , Quinolonas/uso terapêutico , Adolescente , Antipsicóticos/efeitos adversos , Aripiprazol , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Criança , Manual Diagnóstico e Estatístico de Transtornos Mentais , Agonistas de Dopamina/efeitos adversos , Monitoramento de Medicamentos , Resistência a Medicamentos , Feminino , Humanos , Masculino , Piperazinas/efeitos adversos , Escalas de Graduação Psiquiátrica , Quinolonas/efeitos adversos , Receptores de Dopamina D2/agonistas , Agonistas do Receptor 5-HT1 de Serotonina/efeitos adversos , Agonistas do Receptor 5-HT1 de Serotonina/uso terapêutico , Antagonistas do Receptor 5-HT2 de Serotonina/efeitos adversos , Antagonistas do Receptor 5-HT2 de Serotonina/uso terapêutico , Índice de Gravidade de Doença , Turquia
12.
Dalton Trans ; 51(46): 17753-17761, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36346270

RESUMO

We have performed and analyzed the first combined 151Eu and 57Fe nuclear resonant vibrational spectroscopy (NRVS) for naturally abundant KEu(III)[Fe(II)(CN)6] and Eu(III)[Fe(III)(CN)6] complexes. Comparison of the observed 151Eu vs.57Fe NRVS spectroscopic features confirms that Eu(III) in both KEu(III)[Fe(II)(CN)6] and Eu(III)[Fe(III)(CN)6] occupies a position outside the [Fe(CN)6] core and coordinates to the N atoms of the CN- ions, whereas Fe(III) or Fe(II) occupies the site inside the [Fe(CN)6]4- core and coordinates to the C atoms of the CN- ions. In addition to the spectroscopic interest, the results from this study provide invaluable insights for the design and evaluation of the nanoparticles of such complexes as potential cellular contrast agents for their use in magnetic resonance imaging. The combined 151Eu and 57Fe NRVS measurements are also among the first few explorations of bi-isotopic NRVS experiments.


Assuntos
Compostos Ferrosos , Ferro , Ferro/química , Análise Espectral
13.
Oper Dent ; 36(6): 572-80, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21913862

RESUMO

OBJECTIVE: This study aimed to evaluate the color change and clinical periodontal parameters and to analyze the interleukin­1 beta (IL-1ß) and interleukin-10 (IL-10) levels in gingival crevicular fluid (GCF) of patients treated with different bleaching systems. MATERIALS AND METHODS: According to pre-established criteria, 30 healthy volunteers were selected and randomly divided into three groups (n=10): G1, home bleaching (Opalescence 35% Carbamide Peroxide, CP); G2, chemically activated office bleaching (Opalescence Xtra Boost 38% Hydrogen Peroxide, HP); G3, light-activated office bleaching (Opalescence Xtra 35% HP). Treatments were applied according to the manufacturer's recommendations. After shade evaluation, clinical periodontal parameters were evaluated as follows: gingival index (GI), plaque index (PI), and bleeding on probing (BOP). GCF were collected from six maxillary sites per patient at baseline (T0), one day (T1) after bleaching treatments, and 15 days (T2) after bleaching treatments and analyzed for IL-1ß and IL-10 by enzyme-linked immunosorbent assay. Data were subjected to statistical analysis (p<0.05). RESULTS: Spectrophotometer readings exhibited significant differences among the groups (p<0.05). The ΔE values (color change) of G3 were statistically higher than the other groups (p<0.05). The PI of G3 after 15 days was significantly higher than the PI of G2 after 15 days (p<0.05). The GI of G2 was lower than that of G1 and G3 before bleaching (p<0.05). According to BOP, no significant differences were found among the groups at any time intervals (p>0.05). In G3, the total amount of IL-1ß after 15 days was higher than the amount before bleaching (p<0.05). The IL-10 total amount and concentration levels did not exhibit any significant differences among the groups or by time (p>0.05). CONCLUSION: Home and chemically activated bleaching systems could be considered as safer in tooth whitening and maintaining gingival health when compared with a light-activated bleaching system, which might lead to increased proinflammatory cytokine (IL-1ß).


Assuntos
Gengiva/efeitos dos fármacos , Gengiva/efeitos da radiação , Interleucina-1beta/análise , Clareamento Dental/métodos , Adolescente , Adulto , Análise de Variância , Peróxido de Carbamida , Índice de Placa Dentária , Feminino , Líquido do Sulco Gengival/química , Humanos , Peróxido de Hidrogênio/administração & dosagem , Interleucina-10/análise , Luz/efeitos adversos , Masculino , Índice Periodontal , Peróxidos/administração & dosagem , Espectrofotometria , Estatísticas não Paramétricas , Clareamento Dental/efeitos adversos , Clareadores Dentários/administração & dosagem , Descoloração de Dente/terapia , Ureia/administração & dosagem , Ureia/análogos & derivados , Adulto Jovem
14.
Brain Inform ; 8(1): 19, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34586519

RESUMO

Interest in the studying of functional connections in the brain has grown considerably in the last decades, as many studies have pointed out that alterations in the interaction among brain areas can play a role as markers of neurological diseases. Most studies in this field treat the brain network as a system of connections stationary in time, but dynamic features of brain connectivity can provide useful information, both on physiology and pathological conditions of the brain. In this paper, we propose the application of a computational methodology, named Particle Filter (PF), to study non-stationarities in brain connectivity in functional Magnetic Resonance Imaging (fMRI). The PF algorithm estimates time-varying hidden parameters of a first-order linear time-varying Vector Autoregressive model (VAR) through a Sequential Monte Carlo strategy. On simulated time series, the PF approach effectively detected and enabled to follow time-varying hidden parameters and it captured causal relationships among signals. The method was also applied to real fMRI data, acquired in presence of periodic tactile or visual stimulations, in different sessions. On these data, the PF estimates were consistent with current knowledge on brain functioning. Most importantly, the approach enabled to detect statistically significant modulations in the cause-effect relationship between brain areas, which correlated with the underlying visual stimulation pattern presented during the acquisition.

16.
IEEE Trans Image Process ; 18(5): 982-94, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19336309

RESUMO

We investigate the source separation problem of random fields within a Bayesian framework. The Bayesian formulation enables the incorporation of prior image models in the estimation of sources. Due to the intractability of the analytical solution, we resort to numerical methods for the joint maximization of the a posteriori distribution of the unknown variables and parameters. We construct the prior densities of pixels using Markov random fields based on a statistical model of the gradient image, and we use a fully Bayesian method with modified-Gibbs sampling. We contrast our work to approximate Bayesian solutions such as Iterated Conditional Modes (ICM) and to non-Bayesian solutions of ICA variety. The performance of the method is tested on synthetic mixtures of texture images and astrophysical images under various noise scenarios. The proposed method is shown to outperform significantly both its approximate Bayesian and non-Bayesian competitors.

17.
IEEE Trans Image Process ; 28(4): 1748-1758, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30371367

RESUMO

Synthetic aperture radar (SAR) and ultrasound (US) are two important active imaging techniques for remote sensing, both of which are subject to speckle noise caused by coherent summation of back-scattered waves and subsequent nonlinear envelope transformations. Estimating the characteristics of this multiplicative noise is crucial to develop denoising methods and to improve statistical inference from remote sensing images. In this paper, reversible jump Markov chain Monte Carlo (RJMCMC) algorithm has been used with a wider interpretation and a recently proposed RJMCMC-based Bayesian approach, trans-space RJMCMC, has been utilized. The proposed method provides an automatic model class selection mechanism for remote sensing images of SAR and US where the model class space consists of popular envelope distribution families. The proposed method estimates the correct distribution family, as well as the shape and the scale parameters, avoiding performing an exhaustive search. For the experimental analysis, different SAR images of urban, forest and agricultural scenes, and two different US images of a human heart have been used. Simulation results show the efficiency of the proposed method in finding statistical models for speckle.

18.
Biochemistry ; 47(25): 6612-27, 2008 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-18512953

RESUMO

We have used (57)Fe nuclear resonance vibrational spectroscopy (NRVS) to study the Fe(2)S(2)(Cys)(4) sites in oxidized and reduced [2Fe-2S] ferredoxins from Rhodobacter capsulatus (Rc FdVI) and Aquifex aeolicus (Aa Fd5). In the oxidized forms, nearly identical NRVS patterns are observed, with strong bands from Fe-S stretching modes peaking around 335 cm(-1), and additional features observed as high as the B(2u) mode at approximately 421 cm(-1). Both forms of Rc FdVI have also been investigated by resonance Raman (RR) spectroscopy. There is good correspondence between NRVS and Raman frequencies, but because of different selection rules, intensities vary dramatically between the two kinds of spectra. For example, the B(3u) mode at approximately 288 cm(-1), attributed to an asymmetric combination of the two FeS(4) breathing modes, is often the strongest resonance Raman feature. In contrast, it is nearly invisible in the NRVS, as there is almost no Fe motion in such FeS(4) breathing. NRVS and RR analysis of isotope shifts with (36)S-substituted into bridging S(2-) ions in Rc FdVI allowed quantitation of S(2-) motion in different normal modes. We observed the symmetric Fe-Fe stretching mode at approximately 190 cm(-1) in both NRVS and RR spectra. At still lower energies, the NRVS presents a complex envelope of bending, torsion, and protein modes, with a maximum at 78 cm(-1). The (57)Fe partial vibrational densities of states (PVDOS) were interpreted by normal-mode analysis with optimization of Urey-Bradley force fields. Progressively more complex D(2h) Fe(2)S(2)S'(4), C(2h) Fe(2)S(2)(SCC)(4), and C(1) Fe(2)S(2)(Cys)(4) models were optimized by comparison with the experimental spectra. After modification of the CHARMM22 all-atom force field by the addition of refined Fe-S force constants, a simulation employing the complete protein structure was used to reproduce the PVDOS, with better results in the low frequency protein mode region. This process was then repeated for analysis of data on the reduced FdVI. Finally, the degree of collectivity was used to quantitate the delocalization of the dynamic properties of the redox-active Fe site. The NRVS technique demonstrates great promise for the observation and quantitative interpretation of the dynamical properties of Fe-S proteins.


Assuntos
Proteínas de Bactérias/química , Ferredoxinas/química , Análise Espectral Raman/métodos , Análise Espectral/métodos , Algoritmos , Bactérias/metabolismo , Ferro/química , Modelos Moleculares , Oxirredução , Conformação Proteica , Rhodobacter capsulatus/metabolismo , Enxofre/química , Vibração
19.
Biotech Histochem ; 93(5): 340-353, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29671622

RESUMO

Impairment of cardiac function causes renal damage. Renal failure after heart failure is attributed to hemodynamic derangement including reduced renal perfusion and increased venous pressure. One mechanism involves apoptosis and is defined as cardiorenal syndrome type 1. Erythropoietin (EPO) is a cytokine that induces erythropoiesis under hypoxic conditions. Hypoxia inducible factor 1 alpha (HIF-1α) plays a regulatory role in cellular response to hypoxia. Protective effects of EPO on heart, kidney and nervous system are unrelated to red blood cell production. We investigated early changes in and effects of EPO on renal tissues of rats with myocardial infarction by morphology and immunohistochemistry. Coronary artery ligation was used to induce myocardial infarction in Wistar rats. Group 1 comprised sham operated rats; groups 2, 3 and 4 included rats after coronary artery ligation that were sacrificed 6 h after ligation and that were treated with saline, 5,000 U/kg EPO or 10,000 U/kg EPO, respectively; group 5 included rats sacrificed 1 h after ligation. Group 2 showed increased renal tubule damage. Significantly less tubule damage was observed in EPO treated groups. EPO and EPO receptor (EPO-R) immunostaining intensities increased slightly for group 5 and became more intense for group 2. EPO and EPO-R immunostaining was observed in the interstitial area, glomerular cells and tubule epithelial cells of EPO treated groups. HIF-1α immunostaining was observed in collecting tubules in the medulla only in group 2. Caspase-3 immunostaining is an indicator of apoptosis. Caspase-3 staining intensity decreased in renal medulla of EPO treated groups. EPO treatment may exert a protective effect on the renal tissues of patients with cardiorenal syndrome.


Assuntos
Eritropoetina/farmacologia , Insuficiência Cardíaca/metabolismo , Hipóxia/metabolismo , Rim/efeitos dos fármacos , Rim/patologia , Animais , Apoptose/efeitos dos fármacos , Insuficiência Cardíaca/tratamento farmacológico , Hipóxia/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imuno-Histoquímica/métodos , Masculino , Ratos Wistar
20.
Eye (Lond) ; 31(5): 781-787, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28157224

RESUMO

PurposeTo compare the clinical outcome with different treatment regimens in Acute Adenoviral Keratoconjunctivitis (AAK).MethodsThe records of 110 patients diagnosed as AAK in two tertiary eye care centers were evaluated retrospectively. The treatment regimen, follow-up duration, time until improvement of the symptoms, visual acuity, clinical findings, Schirmer's test and the Ocular Surface Disease Index (OSDI) score at the first day, first week and third week were recorded. The Kruskal-Wallis Test and Chi-square test were used for comparison of quantitative and categorical variables, respectively.ResultsForty six patients were receiving topical corticosteroids (Group 1), 32 topical 2% Cyclosporin A (CsA) (Group 2) and 32 only artificial tears (Group 3). Mean time until resolution of the symptoms was lowest in Group 1 (9.5±4.9 days) and highest in Group 3 (13.3±4.2 days)(p: 0.001). OSDI scores at the first and third weeks were highest in Group 3 (52.4±16.4 and 32.3±13.0) and lowest in Group 1 (41.0±21.3 and 23.9±13.2)(p: 0.01 and p: 0.009). At day 21, percentage of the patients with subepthelial infiltrates was the highest in Group 3 (63.4%) and lowest in Group 1 (42.5%).ConclusionsThe symptoms were less severe and had a shorter duration with topical corticosteroids and CsA when compared with palliative therapy. Topical 2% CsA may inhibit development of corneal subepithelial infiltrates when used in the acute phase of infection, similar to corticosteroids.


Assuntos
Infecções por Adenovirus Humanos/tratamento farmacológico , Ciclosporina/administração & dosagem , Infecções Oculares Virais/tratamento farmacológico , Ceratoconjuntivite/tratamento farmacológico , Prednisolona/análogos & derivados , Doença Aguda , Feminino , Seguimentos , Glucocorticoides/administração & dosagem , Humanos , Imunossupressores/administração & dosagem , Lubrificantes Oftálmicos/administração & dosagem , Masculino , Soluções Oftálmicas , Prednisolona/administração & dosagem , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual
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