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1.
Sci Rep ; 14(1): 14544, 2024 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914697

RESUMO

Retinoblastoma is one of the most common ocular malignancies in children. Bmi-1, a member of the Polycomb group family of transcriptional repressors, is expressed in a variety of tumors. The purpose of our study was to explore the role of Bmi-1 in retinoblastoma. RT-qPCR and western blot were used for calculating the mRNA and protein levels of Bmi-1 and RKIP. MTT, Wound healing and Transwell assays were performed to measure the proliferation, migration and invasion in retinoblastoma cells. Cell apoptosis was detected by flow cytometry. The volume and mass of transplanted tumors were detected in nude mice. Bmi-1 was over expressed, and RKIP was low expressed in retinoblastoma cells. Bmi-1 promoted cell proliferation, migration and invasion and suppressed cell apoptosis of Y79 and SO-RB50 cells. Downregulation of Bmi-1 and overexpression of RKIP inhibited cell proliferation, migration and invasion, and increased cell apoptosis. The functions of Bmi-1 knockdown on retinoblastoma cells were blocked by RKIP knockdown, but promoted by RKIP. Down-regulated Bmi-1 inhibited xenograft tumor growth, and RKIP exacerbated this inhibitory effect. Bmi-1 served as a potential therapeutic target for improving the efficacy of clinical treatment in retinoblastoma. All the findings revealed the functions of Bmi-1/RKIP axis in retinoblastoma tumorigenesis.


Assuntos
Apoptose , Movimento Celular , Proliferação de Células , Camundongos Nus , Invasividade Neoplásica , Proteína de Ligação a Fosfatidiletanolamina , Complexo Repressor Polycomb 1 , Retinoblastoma , Humanos , Retinoblastoma/patologia , Retinoblastoma/metabolismo , Retinoblastoma/genética , Complexo Repressor Polycomb 1/metabolismo , Complexo Repressor Polycomb 1/genética , Apoptose/genética , Movimento Celular/genética , Animais , Linhagem Celular Tumoral , Camundongos , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Proteína de Ligação a Fosfatidiletanolamina/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias da Retina/patologia , Neoplasias da Retina/metabolismo , Neoplasias da Retina/genética
2.
Inorg Chem ; 63(5): 2431-2442, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38258796

RESUMO

The coupled NO-vibrational peaks [IR νNO 1775 s, 1716 vs, 1668 vs cm-1 (THF)] between two adjacent [Fe(NO)2] groups implicate the electron delocalization nature of the singly O-phenoxide-bridged dinuclear dinitrosyliron complex (DNIC) [Fe(NO)2(µ-ON2Me)Fe(NO)2] (1). Electronic interplay between [Fe(NO)2] units and [ON2Me]- ligand in DNIC 1 rationalizes that "hard" O-phenoxide moiety polarizes iron center(s) of [Fe(NO)2] unit(s) to enforce a "constrained" π-conjugation system acting as an electron reservoir to bestow the spin-frustrated {Fe(NO)2}9-{Fe(NO)2}9-[·ON2Me]2- electron configuration (Stotal = 1/2). This system plays a crucial role in facilitating the ligand-based redox interconversion, working in harmony to control the storage and redox-triggered transport of the [Fe(NO)2]10 unit, while preserving the {Fe(NO)2}9 core in DNICs {Fe(NO)2}9-[·ON2Me]2- [K-18-crown-6-ether)][(ON2Me)Fe(NO)2] (2) and {Fe(NO)2}9-[·ON2Me] [(ON2Me)Fe(NO)2][PF6] (3). Electrochemical studies suggest that the redox interconversion among [{Fe(NO)2}9-[·ON2Me]2-] DNIC 3 ↔ [{Fe(NO)2}9-[ON2Me]-] ↔ [{Fe(NO)2}9-[·ON2Me]] DNIC 2 are kinetically feasible, corroborated by the redox shuttle between O-bridged dimerized [(µ-ONMe)2Fe2(NO)4] (4) and [K-18-crown-6-ether)][(ONMe)Fe(NO)2] (5). In parallel with this finding, the electronic structures of [{Fe(NO)2}9-{Fe(NO)2}9-[·ON2Me]2-] DNIC 1, [{Fe(NO)2}9-[·ON2Me]2-] DNIC 2, [{Fe(NO)2}9-[·ON2Me]] DNIC 3, [{Fe(NO)2}9-[ONMe]-]2 DNIC 4, and [{Fe(NO)2}9-[·ONMe]2-] DNIC 5 are evidenced by EPR, SQUID, and Fe K-edge pre-edge analyses, respectively.

3.
Small ; : e2307910, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072788

RESUMO

To investigate synergistic effect between geometric and electronic structures on directing CO2 RR selectivity, water phase synthetic protocol and surface architecture engineering strategy are developed to construct monodispersed Bi-doped Cu-based nanocatalysts. The strongly correlated catalytic directionality and Bi3+ dopant can be rationalized by the regulation of [*COOH]/[*CO] adsorption capacities through the appropriate doping of Bi3+ electronic modulator, resulting in volcano relationship between FECO /TOFCO and surface EVBM values. Spectroscopic study reveals that the dual-site binding mode ([Cu─µâ”€C(═O)O─Bi3+ ]) enabled by Cu1 Bi3+ 2 motif in single-phase Cu150 Bi1 nanocatalyst drives CO2-to-CO conversion. In contrast, the study of dynamic Bi speciation and phase transformation in dual-phase Cu50 Bi1 nanocatalyst unveils that the Bi0 -Bi0 contribution emerges at the expense of BOC phase, suggesting metallic Bi0 phase acting as [H]˙ formation center switches CO2 RR selectivity toward CO2-to-HCOO- conversion via [*OCHO] and [*OCHOK] intermediates. This work provides significant insight into how geometric architecture cooperates with electronic effect and catalytic motif/phase to guide the selectivity of electrocatalytic CO2 reduction through the distinct surface-bound intermediates and presents molecular-level understanding of catalytic mechanism for CO/HCOO- formation.

4.
Medicine (Baltimore) ; 102(33): e34850, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37603506

RESUMO

To evaluate the impact of strabismus surgery on sensory eye balance in patients with intermittent exotropia (IXT). In total, 112 IXT patients with ocular alignment at the first strabismus surgery and 34 controls were enrolled from January 2015 to December 2016 in this retrospective study. The effective contrast ratio (ECR) of non-dominant eyes was measured by binocular phase combination paradigm before and 3 months after surgery, and the degree of sensory eye balance was quantitatively evaluated and compared between IXT patients and controls. The preoperative and postoperative mean ECRs of IXT patients were 0.492 ±â€…0.182 and 0.684 ±â€…0.198, respectively, which were significantly lower than those of the control group (0.896 ±â€…0.214, both P < .001). In addition, the postoperative ECR was significantly higher than the preoperative ECR (P < .001). The ECR change was not correlated with age orstrabismus degree measured with a6 m accommodative target (both P > .05), while significant negative correlation was observed between the ECR change and strabismus degree measured with a 33 cm accommodative target (P = .002). Strabismus surgery can significantly reduce the degree of sensory eye imbalance in patients with IXT, while further treatment aimed at rebalancing the ocular dominance might be necessary for more efficient binocular visual processing in the long-term.


Assuntos
Exotropia , Estrabismo , Humanos , Exotropia/cirurgia , Estudos Retrospectivos , Olho , Acomodação Ocular , Doença Crônica
5.
J Pediatr Ophthalmol Strabismus ; 60(2): 120-130, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35611820

RESUMO

PURPOSE: To quantitatively evaluate and compare binocular visual perception between normal individuals and patients with different types of strabismus using a binocular phase combination paradigm. METHODS: A total of 117 participants were included in the study and were divided into the normal control group, exophoria group, comitant exotropia group, comitant esotropia group, and special strabismus group according to the type of strabismus. The effective contrast ratio (ECR) was measured to quantitatively evaluate binocular visual perception. Binocular fusion was evaluated using the Worth 4-dots flashlight. Stereoacuity was detected by the Titmus stereo test. RESULTS: The mean ECRs in the normal control group, exophoria group, comitant exotropia group, comitant esotropia group, and special strabismus group were 0.896 ± 0.214, 0.824 ± 0.234, 0.520 ± 0.279, 0.261 ± 0.139, and 0.461 ± 0.243, respectively. Within-group differences in the ECR were statistically significant. In addition, there was no statistically significant difference between the normal control group and exophoria group, and the concomitant exotropia group and special strabismus group and the other groups were statistically significant in pairwise comparison. The binocular visual perception was basically balanced in the exotropia group and most imbalanced in the comitant esotropia group, followed by the comitant exotropia group and the special strabismus group. The results also indicated that the decreased ECR was related to poor stereopsis and ECR had a significant positive correlation with binocular fusion function. CONCLUSIONS: Different types of strabismus have different degrees of visual perception imbalance. The binocular phase combination paradigm applied in this study can quickly and accurately quantify the degree of binocular visual perception imbalance in patients with strabismus by measuring ECR. [J Pediatr Ophthalmol Strabismus. 2023;60(2):120-130.].


Assuntos
Percepção de Profundidade , Estrabismo , Visão Binocular , Adolescente , Criança , Feminino , Humanos , Masculino , Estrabismo/diagnóstico
6.
Inorg Chem ; 61(51): 20719-20724, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36516228

RESUMO

Nanoscale zerovalent iron (NZVI) features potential application to biomedicine, (electro-/photo)catalysis, and environmental remediation. However, multiple-synthetic steps and limited ZVI content prompt the development of a novel strategy for efficient preparation of NZVI composites. Herein, a dinitrosyl iron complex [(N3MDA)Fe(NO)2] (1-N3MDA) was explored as a molecular precursor for one-pot photosynthesis of a cubic Fe@Fe3O4 core-shell nanoparticle (ZVI% = 60%) well-dispersed in an N-doping carbonaceous polymer (NZVI@NC). Upon photolysis of 1-N3MDA, photosensitizer Eosin Y, and sacrificial reductant TEA, the α-diimine N3MDA and noninnocent NO ligands (1) enable the slow reduction of 1-N3MDA into an unstable [(N3MDA)Fe(NO)2]- species, (2) serve as a capping reagent for controlled nucleation of zerovalent Fe atom into Fe nanoparticle, and (3) promote the polymerization of degraded Eosin Y with N3MDA yielding an N-doping carbonaceous matrix in NZVI@NC. This discovery of a one-pot photosynthetic process for NZVI@NC inspires continued efforts on its application to photolytic water splitting and ferroptotic chemotherapy in the near future.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Amarelo de Eosina-(YS) , Ferro , Água , Substâncias Redutoras
7.
J Clin Psychiatry ; 82(2)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33988925

RESUMO

OBJECTIVE: Suicide is a priority health problem. Suicide assessment depends on imperfect clinician assessment with minimal ability to predict the risk of suicide. Machine learning/deep learning provides an opportunity to detect an individual at risk of suicide to a greater extent than clinician assessment. The present study aimed to use deep learning of structural magnetic resonance imaging (MRI) to create an algorithm for detecting suicidal ideation and suicidal attempts. METHODS: We recruited 4 groups comprising a total of 186 participants: 33 depressive patients with suicide attempt (SA), 41 depressive patients with suicidal ideation (SI), 54 depressive patients without suicidal thoughts (DP), and 58 healthy controls (HCs). The confirmation of depressive disorder, SA and SI was based on psychiatrists' diagnosis and Mini-International Neuropsychiatric Interview (MINI) interviews. In the generalized q-sampling imaging (GQI) dataset, indices of generalized fractional anisotropy (GFA), the isotropic value of the orientation distribution function (ISO), and normalized quantitative anisotropy (NQA) were separately trained in convolutional neural network (CNN)-based deep learning and DenseNet models. RESULTS: From the results of 5-fold cross-validation, the best accuracies of the CNN classifier for predicting SA, SI, and DP against HCs were 0.916, 0.792, and 0.589, respectively. In SA-ISO, DenseNet outperformed the simple CNNs with a best accuracy from 5-fold cross-validation of 0.937. In SA-NQA, the best accuracy was 0.915. CONCLUSIONS: The results showed that a deep learning method based on structural MRI can effectively detect individuals at different levels of suicide risk, from depression to suicidal ideation and attempted suicide. Further studies from different populations, larger sample sizes, and prospective follow-up studies are warranted to confirm the utility of deep learning methods for suicide prevention and intervention.


Assuntos
Encéfalo/diagnóstico por imagem , Aprendizado Profundo , Transtorno Depressivo/psicologia , Redes Neurais de Computação , Ideação Suicida , Tentativa de Suicídio/prevenção & controle , Adulto , Algoritmos , Estudos de Casos e Controles , Transtorno Depressivo/diagnóstico por imagem , Feminino , Humanos , Entrevista Psicológica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Medição de Risco , Tentativa de Suicídio/psicologia , Tentativa de Suicídio/estatística & dados numéricos , Adulto Jovem
8.
J Hazard Mater ; 397: 122630, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32416379

RESUMO

In this study, a series of MFI-type zeolites with various compositions were synthesized by a solvent-free synthesis method at a comparatively mild condition. The results of investigations showed that the as-synthesized samples displayed a good crystallinity grade and regular morphology of layered structure. The crystallization process of TS-1 was systematic investigated. It was revealed that the transition stage of crystallization process was the formation of nucleation intermediates (Na2SiF6), which was the key factor for dropping Ti atoms into MFI framework. Meanwhile, it showed a high apparent nucleation activation energy (64.8 kJ mol-1), and low growth activation energy (25.3 kJ mol-1) in a spontaneous nucleation system, and the nucleation activation energy could be reduced to 17.2 kJ mol-1 in non-spontaneous nucleation system. The as-synthesized zeolites were evaluated for their catalytic activity for the degradation of gas-phase styrene. The titanium silicalite-1 sample doped with iron exhibited excellent catalytic activity with 100% degradation of styrene. The method employed in this work not only decreases the production cost and energy-consumption of MFI-type zeolites, but also significantly enhances their production yield. Moreover, it is an efficient pathway to solve the pollution of volatile organic compounds using solid waste.

9.
Dalton Trans ; 48(18): 6040-6050, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-30734799

RESUMO

The synthesis, characterization and transformation of the thermally unstable {Fe(NO)2}9 dinitrosyl iron complex (DNIC) [(OMe)2Fe(NO)2]- (2) were investigated. The {Fe(NO)2}9 DNIC 2 characterized by single-crystal X-ray diffraction is exclusively stabilized by the weak intermolecular [Fe(OMe)2(K+)] interactions (O(3)K(1) and O(4)K(1) distances of 2.818(3) and 2.810(3) Å, respectively). The binding affinity of chalcogenolate-containing ligands toward the {Fe(NO)2}9 motif follows the series [SEt]- > [SPh]- > [OPh]- > [OMe]-, which is dictated by the synergistic cooperation of the electron-donating order ([SEt]- > [SPh]- > [OPh]-) and the soft-hard order (from soft to hard, [SEt]- ∼ [SPh]- > [OPh]- > [OMe]-). In comparison with the XAS Fe K-edge pre-edge energy of {Fe(NO)2}9 [(RS)2Fe(NO)2]- (R = Ph (4), Et (5)) and [(PhO)2Fe(NO)2]- (6) DNICs falling within the reported range of 7113.4-7113.9 eV, the distinctive pre-edge energy of 7114.2 eV exhibited by complex 2 suggests that the electronic structure of {Fe(NO)2}9 DNIC 2 may be qualitatively described as a {FeIII(NO-)2}9 electronic structure induced by the dominant ionic character of Fe-OMe bonds, instead of the resonance hybrids of {FeII(NO-)(˙NO)}9 and {FeIII(NO-)2}9 electronic structures induced by the dominant metal-ligand covalency of {Fe(NO)2}9 DNICs 4-6. As shown in TD-DFT computation, the increased population of NO ligands in MO 125ß (45.1% NO) attenuating the OMe-induced polarization imposed on the Fe center through the delocalized covalent nature of Fe-NO bonds supports the lower/synergistic NO/OMe → Fe charge transfer energy (1216 nm) observed in the solid-state UV-vis spectrum of complex 2 compared to those (1140 nm) of complexes 4-6.

10.
Inorg Chem ; 57(23): 14715-14726, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30452243

RESUMO

Electron paramagnetic resonance, IR, single-crystal X-ray diffraction, and density functional theory computation reveal that the electronic structure of α-diimine-coordinated {Fe(NO)2}10-reduced dinitrosyliron complexes (DNICs) may best be described as [{Fe(NO)2}10-L•], with the added electron residing mainly on the α-diimine ligand framework. The combination of electrochemistry, gas chromatography, Fourier transform infrared, X-ray photoelectron spectroscopy, and scanning electron microscopy-energy-dispersive X-ray studies demonstrates that the cathodic potential promotes/triggers the transformation of an α-diimine-coordinated {Fe(NO)2}10-reduced DNIC into a particulate deposit on the electrode, and electrodeposited-film electrodes, CFeO and CFeNO, are kinetically dominant electrocatalysts responsible for hydrogen evolution reaction (HER) from water with quantitative Faradaic efficiency. In comparison with the CFeO electrode reaching a current density of 10 mA/cm2 with an overpotential of 333 mV for HER, the nitrogen-doped iron oxide electrode, CFeNO, requires 147 mV of overpotential to achieve a current density of 10 mA/cm2 in a 1 M NaOH aqueous solution. The CFeNO electrode exhibits higher kinetic efficiency (Tafel slope of 59 mV/dec) than the CFeO electrode (Tafel slope of 122 mV/dec) in alkaline conditions. As opposed to high Rct (74.3 Ω) displayed by the CFeO electrode, the smaller charge-transfer resistance ( Rct) of the CFeNO electrode (34.0 Ω) demonstrated that the better HER catalytic activity may be ascribed to the incorporation of nitrogen into iron oxide architecture, which increases the surface roughness and electroconductivity of the CFeNO electrode (56.9% iron content and nitrogen electron-donating effect) and improves HER catalysis by polarizing the incoming water molecule (acting as a proton tray). This result implicates that a (NH4)2SO4-assisted nitrogen-doping strategy is a direct and effective method to realize synergistic regulation of the reaction dynamics, catalytically active sites and electronic conductivity, endowing this nitrogen-doped material CFeNO electrode as a promising HER electrocatalyst under alkaline conditions.

11.
Molecules ; 23(10)2018 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-30301224

RESUMO

Nitroxyl (HNO) plays a critical role in many physiological processes which includes vasorelaxation in heart failure, neuroregulation, and myocardial contractility. Powerful imaging tools are required to obtain information for understanding the mechanisms involved in these in vivo processes. In order to develop a rapid and high sensitive probe for HNO detection in living cells and the zebrafish model organism, 2-((2-(benzothiazole-2yl)benzylidene) amino)benzoic acid (AbTCA) as a ligand, and its corresponding copper(II) complex Cu(II)-AbTCA were synthesized. The reaction results of Cu(II)-AbTCA with Angeli's salt showed that Cu(II)-AbTCA could detect HNO quantitatively in a range of 40⁻360 µM with a detection limit of 9.05 µM. Furthermore, Cu(II)-AbTCA is more selective towards HNO over other biological species including thiols, reactive nitrogen, and reactive oxygen species. Importantly, Cu(II)-AbTCA was successfully applied to detect HNO in living cells and zebrafish. The collective data reveals that Cu(II)-AbTCA could be used as a potential probe for HNO detection in living systems.


Assuntos
Cobre/química , Óxidos de Nitrogênio/química , Peixe-Zebra , Animais , Corantes Fluorescentes/química , Humanos , Nitritos/química , Óxidos de Nitrogênio/farmacologia
12.
J Am Chem Soc ; 139(1): 67-70, 2017 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-28030770

RESUMO

To carry and deliver nitric oxide with a controlled redox state and rate is crucial for its pharmaceutical/medicinal applications. In this study, the capability of cationic {Fe(NO)2}9 dinitrosyl iron complexes (DNICs) [(RDDB)Fe(NO)2]+ (R = Me, Et, Iso; RDDB = N,N'-bis(2,6-dialkylphenyl)-1,4-diaza-2,3-dimethyl-1,3-butadiene) carrying nearly unperturbed nitric oxide radical to form [(RDDB)Fe(NO)2(•NO)]+ was demonstrated and characterized by IR, UV-vis, EPR, NMR, and single-crystal X-ray diffractions. The unique triplet ground state of [(RDDB)Fe(NO)2(•NO)]+ results from the ferromagnetic coupling between two strictly orthogonal orbitals, one from Fe dz2 and the other a π*op orbital of a unique bent axial NO ligand, which is responsible for the growth of a half-field transition (ΔMS = 2) from 70 to 4 K in variable-temperature EPR measurements. Consistent with the NO radical character of coordinated axial NO ligand in complex [(MeDDB)Fe(NO)2(•NO)]+, the simple addition of MeCN/H2O into CH2Cl2 solution of complexes [(RDDB)Fe(NO)2(•NO)]+ at 25 °C released NO as a neutral radical, as demonstrated by the formation of [S5Fe(NO)2]- from [S5Fe(µ-S)2FeS5]2-.


Assuntos
Ferro/química , Óxido Nítrico/química , Óxidos de Nitrogênio/química , Radicais Livres/química , Conformação Molecular , Teoria Quântica
13.
J Am Chem Soc ; 138(13): 4626-33, 2016 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-26974858

RESUMO

(S)-3,4-Dihydroxybutyric acid ((S)-3,4-DHBA), an endogenous straight chain fatty acid, is a normal human urinary metabolite and can be obtained as a valuable chiral biomass for synthesizing statin-class drugs. Hence, its epoxide derivatives should serve as promising monomers for producing biocompatible polymers via alternating copolymerization with carbon dioxide. In this report, we demonstrate the production of poly(tert-butyl 3,4-dihydroxybutanoate carbonate) from racemic-tert-butyl 3,4-epoxybutanoate (rac-(t)Bu 3,4-EB) and CO2 using bifunctional cobalt(III) salen catalysts. The copolymer exhibited greater than 99% carbonate linkages, 100% head-to-tail regioselectivity, and a glass-transition temperature (Tg) of 37 °C. By way of comparison, the similarly derived polycarbonate from the sterically less congested monomer, methyl 3,4-epoxybutanoate, displayed 91.8% head-to-tail content and a lower Tg of 18 °C. The tert-butyl protecting group of the pendant carboxylate group was removed using trifluoroacetic acid to afford poly(3,4-dihydroxybutyric acid carbonate). Depolymerization of poly(tert-butyl 3,4-dihydroxybutanoate carbonate) in the presence of strong base results in a stepwise unzipping of the polymer chain to yield the corresponding cyclic carbonate. Furthermore, the full degradation of the acetyl-capped poly(potassium 3,4-dihydroxybutyrate carbonate) resulted in formation of the biomasses, ß-hydroxy-γ-butyrolacetone and 3,4-dihydroxybutyrate, in water (pH = 8) at 37 °C. In addition, water-soluble platinum-polymer conjugates were synthesized with platinum loading of 21.3-29.5%, suggesting poly(3,4-dihydroxybutyric acid carbonate) and related derivatives may serve as platinum drug delivery carriers.


Assuntos
Butileno Glicóis/química , Butiratos/química , Dióxido de Carbono/química , Compostos Organoplatínicos/química , Platina/química , Cimento de Policarboxilato/química , Polímeros/química , Carbonatos , Catálise , Cobalto/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Compostos de Epóxi/química , Etilenodiaminas , Humanos , Estrutura Molecular , Polimerização , Água
14.
Graefes Arch Clin Exp Ophthalmol ; 253(3): 431-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25500985

RESUMO

OBJECTIVES: To compare ocular surface changes after strabismus surgery with different incisions. METHODS: One hundred and twenty eyes with exotropia were randomly assigned to Group A (limbal incision) or Group B (fornix incision). Dry eye questionnaire, corneal sensitivity, tear film breakup time (TFBUT), Schirmer I test (SIT), and corneal fluorescein staining (CFS) were assessed at 1 day preoperatively and at different postoperative times. RESULTS: In the A group, dry eye questionnaire scores increased and TFBUT decreased at postoperative weeks 1, 2, and 4. Corneal sensitivity decreased at postoperative weeks 1 and 2. In the B group, dry eye questionnaire scores increased and TFBUT decreased at postoperative weeks 1 and 2. Corneal sensitivity did not change. Postoperative between-group differences were significant in dry eye questionnaire scores (P = 0.0009, 1 week; P < 0.0001, 2 weeks; P = 0.0001, 4 weeks) and TFBUT (P = 0.004, 1 week; P = 0.0003, 2 weeks; P = 0.0001, 4 weeks). Between-group differences in CFS were significant postoperatively (P = 0.045, 1 week; P = 0.020, 2 weeks). CONCLUSION: Compared to fornix incision, limbal incision results in more serious dry eye symptoms and has a greater impact on corneal sensitivity and tear film stability.


Assuntos
Córnea/fisiopatologia , Síndromes do Olho Seco/fisiopatologia , Exotropia/cirurgia , Músculos Oculomotores/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/métodos , Lágrimas/fisiologia , Adolescente , Adulto , Criança , Exotropia/fisiopatologia , Feminino , Fluorofotometria , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Oculomotores/fisiopatologia , Estudos Prospectivos , Inquéritos e Questionários , Técnicas de Sutura , Lágrimas/química
15.
Acta Ophthalmol ; 92(8): e657-62, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24930475

RESUMO

PURPOSE: To compare primary intra-ocular lens (IOL) implantation with use of press-on spherical lens for aphakia correction following unilateral infantile cataract removal. METHODS: Sixty infants with a unilateral cataract underwent cataract surgery and were randomly assigned to the IOL (A group) or no IOL group (B group). Residual refractive error was corrected with spectacles in the A group and a press-on spherical lens was used to treat aphakia in the B group. Grating visual acuity (VA) was measured and patients were followed for up to 1 year. RESULTS: LogMAR VA in the operated eyes of both groups was significantly better 1 year than 1 month after surgery. Mean logMAR VA difference between 1 year and 1 month after surgery was higher in the A group (0.457 ± 0.110) than in the B group (0.323 ± 0.114, p < 0.0001). Serious inflammation occurred significantly more often in the A group than in the B group (p = 0.007). Visual axis opacity occurred more often in the A group than in the B group (pupillary membrane: A: six eyes, 20%, B: none, p = 0.024; lens reproliferation: A: 10 eyes, 33%, B: two eyes, 7%, p = 0.021). Glaucoma occurred equally in both groups (p = 0.612). No other complications occurred. CONCLUSIONS: Primary IOL implantation appears to be a relatively safe, effective optical correction strategy following unilateral cataract extraction in this age group. Patients for whom an IOL is not suitable can be treated with a press-on spherical lens for optical correction.


Assuntos
Afacia Pós-Catarata/cirurgia , Catarata/congênito , Implante de Lente Intraocular , Facoemulsificação , Astigmatismo/fisiopatologia , Bandagens , Pré-Escolar , Óculos , Feminino , Humanos , Hiperopia/fisiopatologia , Lactente , Masculino , Miopia/fisiopatologia , Estudos Prospectivos , Privação Sensorial , Transtornos da Visão/reabilitação , Acuidade Visual/fisiologia
16.
Nanotechnology ; 25(16): 165601, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24670949

RESUMO

Ultrathin percolated high-Ku magnetic films with thicknesses of 2 nm are realized simply by using sputter deposition and post annealing. L11 CoPt:MgO, with Ku on the order of 10(7) erg cm(-3), was deposited on a MgO(111) substrate at 350 °C, followed by post annealing to induce complete segregation of the added MgO dopants. The optimized film shows significant enhancement of the out-of-plane coercivity, approximately an order of magnitude greater than that of the CoPt binary film, a remanence ratio close to unity, considerably reduced in-plane magnetization, sharp perpendicular magnetic reversal, and reduced surface roughness in the range of a few angstroms. Microstructure results indicate that MgO precipitates into grains within the interconnected L11 grains after appropriate post annealing. The MgO grains, with sizes in the range 2-7 nm, form coherent interfaces to the CoPt matrix and penetrate through the whole depth of the film. The development of ideal non-magnetic domain wall pinning sites explains the optimization of the perpendicular magnetic properties. The advantages of a simple fabrication process, a thin film layer structure, and remarkable enhancement of the magnetic characteristics demanded by ultrahigh-density recording reveal its potential for practical applications.

17.
BMC Ophthalmol ; 13: 12, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23587195

RESUMO

BACKGROUND: Scleral buckling surgery and pars plana vitrectomy are competing methods in the treatment of retinal detachment. The recent development of spectral-domain optical coherence tomography (SD-OCT) has dramatically improved the visualization of the photoreceptor layer relative to conventional OCT, and offers new opportunities to investigate the discordances between anatomic and functional outcomes after retinal detachment surgery. Hence, the study aim was to use SD-OCT to compare the postoperative macular recovery between scleral buckling and vitrectomy for macular-off rhegmatogenous retinal detachment. METHODS: In this retrospective observational case series, we observed 32 patients who underwent scleral buckling surgery (group 1) and 26 patients who underwent pars plana vitrectomy (group 2) as the primary surgery for macula-off rhegmatogenous retinal detachment. OCT was used to examine microstructural changes in the macular area. RESULTS: The mean visual acuity improvement was 0.4 ± 0.8 logMAR in group 1 and 0.7 ± 0.9 logMAR in group 2. As detected by SD-OCT, subretinal fluid was present in 26 of the group 1 eyes (81.3%) and 5 of the group 2 eyes (19.2%) at 8 weeks postoperatively.This difference was statistically significant (Fisher's exact test, P < 0.05). Moreover, detection by SD-OCT revealed epiretinal membranes in 5 of the group 1 eyes (15.6%) and 11 of the group 2 eyes (42.3%), a difference that was statistically significant (Fisher's exact test, P < 0.05). CONCLUSIONS: Macular recovery and the mean visual acuity differed between the 2 groups of patients. With the help of SD-OCT, we observed that subretinal fluids could persist for a relatively longer period after scleral buckling. Based on our results, we conclude that primary vitrectomy surgery is a better choice for macular recovery of the macula-off rhegmatogenous retinal detachment.


Assuntos
Descolamento Retiniano/cirurgia , Recurvamento da Esclera , Vitrectomia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Descolamento Retiniano/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Vitrectomia/métodos , Adulto Jovem
18.
Foot Ankle Int ; 34(1): 91-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23386767

RESUMO

BACKGROUND: The aim of this study was to evaluate clinical outcomes after surgery for displaced intra-articular fractures using an external fixator and minimal internal fixation. METHODS: In this retrospective observational study, a total of 39 patients (32 [82%] men and 7 [18%] women) with 48 displaced intra-articular calcaneal fractures were included. An extended lateral approach was used to stabilize fractures using multiple sagittal plane screws, axial percutaneous threaded Kirschner wires for the frontal fracture plane, and an external fixator for reduction assistance and maintenance. The following variables were assessed: preoperative and postoperative Böhler's angle; calcaneal length, height, and width; postoperative American Orthopaedic Foot and Ankle Society (AOFAS) scores; and complications. Mean duration of follow-up was 74 ± 26 months. RESULTS: The mean time from surgery to external fixator removal was 12 ± 1 weeks. The mean preoperative Böhler's angle (-3 ± 21 degrees), calcaneal length (7.9 ± 0.6 cm), and calcaneal height (3.6 ± 0.5 cm) were significantly increased (P < .05) at final follow-up (28.3 ± 6.5, 8.3 ± 0.6, and 4.5 ± 0.5, respectively), whereas the mean preoperative calcaneal width (4.2 ± 0.5) was significantly decreased from the final follow-up mean (3.8 ± 0.5). There were no significant differences between any of the normal and postoperative measures. The mean AOFAS score was 82 ± 12. Complications included superficial pin tract infection (n = 7, 15%), superficial wound edge necrosis (n = 4, 8%), and deep infection (n = 2, 4%). CONCLUSION: Our findings suggest that use of an external fixator with minimal internal fixation is an effective option for treating displaced intra-articular calcaneal fractures. LEVEL OF EVIDENCE: Level IV, retrospective case series.


Assuntos
Calcâneo/lesões , Calcâneo/cirurgia , Fixadores Externos , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Adulto , Idoso , Parafusos Ósseos , Calcâneo/diagnóstico por imagem , Feminino , Consolidação da Fratura , Fraturas Ósseas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Radiografia , Estudos Retrospectivos
19.
Inorg Chem ; 52(3): 1631-9, 2013 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-23317006

RESUMO

A reversible redox reaction ({Fe(NO)(2)}(9) DNIC [(NO)(2)Fe(N(Mes)(TMS))(2)](-) (4) ⇄ oxidized-form DNIC [(NO)(2)Fe(N(Mes)(TMS))(2)] (5) (Mes = mesityl, TMS = trimethylsilane)), characterized by IR, UV-vis, (1)H/(15)N NMR, SQUID, XAS, single-crystal X-ray structure, and DFT calculation, was demonstrated. The electronic structure of the oxidized-form DNIC 5 (S(total) = 0) may be best described as the delocalized aminyl radical [(N(Mes)(TMS))(2)](2)(-•) stabilized by the electron-deficient {Fe(III)(NO(-))(2)}(9) motif, that is, substantial spin is delocalized onto the [(N(Mes)(TMS))(2)](2)(-•) such that the highly covalent dinitrosyl iron core (DNIC) is preserved. In addition to IR, EPR (g ≈ 2.03 for {Fe(NO)(2)}(9)), single-crystal X-ray structure (Fe-N(O) and N-O bond distances), and Fe K-edge pre-edge energy (7113.1-7113.3 eV for {Fe(NO)(2)}(10) vs 7113.4-7113.9 eV for {Fe(NO)(2)}(9)), the (15)N NMR spectrum of [Fe((15)NO)(2)] was also explored to serve as an efficient tool to characterize and discriminate {Fe(NO)(2)}(9) (δ 23.1-76.1 ppm) and {Fe(NO)(2)}(10) (δ -7.8-25.0 ppm) DNICs. To the best of our knowledge, DNIC 5 is the first structurally characterized tetrahedral DNIC formulated as covalent-delocalized [{Fe(III)(NO(-))(2)}(9)-[N(Mes)(TMS)](2)(-•)]. This result may explain why all tetrahedral DNICs containing monodentate-coordinate ligands isolated and characterized nowadays are confined in the {Fe(NO)(2)}(9) and {Fe(NO)(2)}(10) DNICs in chemistry and biology.


Assuntos
Aminas/química , Elétrons , Compostos Ferrosos/química , Óxido Nítrico/química , Silanos/química , Compostos Ferrosos/síntese química , Radicais Livres/química , Modelos Moleculares , Estrutura Molecular , Oxirredução
20.
Inorg Chem ; 52(1): 464-73, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23237534

RESUMO

Nitrosylation of high-spin [Fe(κ(2)-O(2)NO)(4)](2-) (1) yields {Fe(NO)}(7) mononitrosyl iron complex (MNIC) [(κ(2)-O(2)NO)(κ(1)-ONO(2))(3)Fe(NO)](2-) (2) displaying an S = 3/2 axial electron paramagnetic resonance (EPR) spectrum (g(⊥) = 3.988 and g(∥) = 2.000). The thermally unstable nitrate-containing {Fe(NO)(2)}(9) dinitrosyl iron complex (DNIC) [(κ(1)-ONO(2))(2)Fe(NO)(2)](-) (3) was exclusively obtained from reaction of HNO(3) and [(OAc)(2)Fe(NO)(2)](-) and was characterized by IR, UV-vis, EPR, superconducting quantum interference device (SQUID), X-ray absorption spectroscopy (XAS), and single-crystal X-ray diffraction (XRD). In contrast to {Fe(NO)(2)}(9) DNIC [(ONO)(2)Fe(NO)(2)](-) constructed by two monodentate O-bound nitrito ligands, the weak interaction between Fe(1) and the distal oxygens O(5)/O(7) of nitrato-coordinated ligands (Fe(1)···O(5) and Fe(1)···O(7) distances of 2.582(2) and 2.583(2) Å, respectively) may play important roles in stabilizing DNIC 3. Transformation of nitrate-containing DNIC 3 into N-bound nitro {Fe(NO)}(6) [(NO)(κ(1)-NO(2))Fe(S(2)CNEt(2))(2)] (7) triggered by bis(diethylthiocarbamoyl) disulfide ((S(2)CNEt(2))(2)) implicates that nitrate-to-nitrite conversion may occur via the intramolecular association of the coordinated nitrate and the adjacent polarized NO-coordinate ligand (nitrosonium) of the proposed {Fe(NO)(2)}(7) intermediate [(NO)(2)(κ(1)-ONO(2))Fe(S(2)CNEt(2))(2)] (A) yielding {Fe(NO)}(7) [(NO)Fe(S(2)CNEt(2))(2)] (6) along with the release of N(2)O(4) (·NO(2)) and the subsequent binding of ·NO(2) to complex 6. The N-bound nitro {Fe(NO)}(6) complex 7 undergoes Me(2)S-promoted O-atom transfer facilitated by imidazole to give {Fe(NO)}(7) complex 6 accompanied by release of nitric oxide. This result demonstrates that nitrate-containing DNIC 3 acts as an active center to modulate nitrate-to-nitrite-to-nitric oxide conversion.


Assuntos
Compostos Férricos/química , Compostos Ferrosos/química , Nitratos/química , Óxido Nítrico/química , Nitritos/química , Compostos Férricos/síntese química , Compostos Ferrosos/síntese química , Conformação Molecular
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