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Our clinical experience led us to realize that craniovertebral junction (CVJ) abnormalities were common in surgical patients with congenital muscular torticollis (CMT). This study aimed to report the concurrence rate of CVJ abnormalities in surgical patients with CMT, along with comprehensive evaluation of type of concurrent CVJ abnormalities. This was a retrospective cohort study in a tertiary hospital, including 41 subjects who underwent surgical release for CMT at the mean age of 8.38 years. The presence of CVJ abnormalities was analyzed, using craniofacial 3-dimensional computed tomography images. The concurrence rate of CVJ abnormalities was 70% in surgical patients with CMT. Subjects with CVJ abnormalities had, on average, 1.48 abnormalities. The CVJ abnormalities were rotation and lateral shift of the atlanto-axial joint along with rotation of atlanto-occipital joint, where rotation of the atlanto-axial joint was most common (82.76%). There is no patient with anterior shift of the atlanto-axial joint. Chronic mechanical tension by the contracted unilateral sternocleidomastoid muscle of CMT could be responsible for concurrent CVJ abnormalities. The CVJ abnormalities are more common in the atlanto-axial joint than in the atlanto-occipital joint. In conclusions, CVJ abnormality seems to be a common concurrent skeletal complication of CMT, at least, in surgical patients. The CVJ abnormality might be included in the list of skeletal complications of CMT. If CVJ abnormalities are significantly more common in surgical patients with CMT, CVJ abnormalities might be one of predictors of surgical patients with CMT.
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Anormalidades Múltiplas/diagnóstico por imagem , Articulação Atlantoaxial/anormalidades , Articulação Atlantoccipital/anormalidades , Torcicolo/congênito , Adolescente , Articulação Atlantoaxial/diagnóstico por imagem , Articulação Atlantoccipital/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Imageamento Tridimensional , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Torcicolo/cirurgia , Adulto JovemRESUMO
Jet-cooled acetaminophen (AAP)-water clusters, AAP-(H2O)1, were investigated by mass-selected resonant two-photon ionization (R2PI), ultraviolet-ultraviolet hole-burning (UV-UV HB), infrared-dip (IR-dip), and infrared-ultraviolet hole-burning (IR-UV HB) spectroscopy. Each syn- and anti-AAP rotamer has three distinctive binding sites (-OH, >CO, and >NH) for a water molecule, thus 6 different AAP-(H2O)1 conformers are expected to exist in the molecular beam. The origin bands of the AAP(OH)-(H2O)1 and AAP(CO)-(H2O)1 conformers (including their syn- and anti-conformers) in the R2PI spectrum are shifted to red and blue compared to those of the AAP monomer, respectively. These frequency shifts upon complexation between a water molecule and a specific binding site of AAP are also predicted by theoretical calculations. The spectral assignments of the origin bands in the R2PI spectra and the IR vibrational bands in the IR-dip spectra of the four lowest-energy conformers of AAP-(H2O)1, [syn- and anti-AAP(OH)-(H2O)1 and syn- and anti-AAP(CO)-(H2O)1], are aided by ab initio and time-dependent density functional theory (TDDFT) calculations. Further investigation of the IR-dip spectra has revealed a hydrogen-bonded NH stretching mode, supporting the presence of the syn-AAP(NH)-(H2O)1 conformer. Moreover, by employing IR-UV HB spectroscopy, we have reconfirmed the existence of the syn-AAP(NH)-(H2O)1 conformer, which happened to be buried underneath the broad background contributed by the AAP(OH)-(H2O)1 conformers. These observations have led us to conclude that all of the possible conformers of AAP-(H2O)1 have been found in this study.
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Acetaminofen/química , Modelos Químicos , Água/química , Gases/química , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
An Al metal plate was ablated by a pulsed Nd-YAG laser to produce nano-structured Al and gamma-Al(2)O(3) in deionized water without any surfactants or catalysts. In this study, direct evidence for the production of Al(3+) ions from the plasma plume is presented for the first time by characterizing the absorption and emission spectra of their [Al(salophen)](+) complex. Very interestingly, a remarkable increase in the fluorescence intensity was observed when the Al(3+) ions, produced via the pulsed laser ablation, complexed with the salophen ligand. This fluorescence 'turn-on' behaviour of [Al(salophen)](+) was investigated by DFT/TD-DFT calculations. Based on these results, mechanisms for the production of aluminium and alumina nanoparticles in the pulsed laser ablation in liquid (PLAL) process are proposed.
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The conformational structures of jet-cooled acetaminophen were investigated in the gas phase by resonant 2-photon ionization and UV-UV hole-burning spectroscopy. In contrast to the results from a previous study, two nearly isoenergetic conformers were distinctly found in a supersonic molecular beam expansion and positively identified as the cis and trans isomers of acetaminophen by UV-UV hole-burning spectroscopy. The 0-0 bands of the cis and trans isomers were found at 33518.7 and 33485.6 cm(-1), respectively. The vibronic bands of the two isomers are close-lying and/or partially overlapping due to the small energy difference (33 cm(-1)) between the two 0-0 bands. As a consequence, the recorded resonant 2-photon ionization spectrum is highly congested in the low excitation energy region, which develops continuously into a featureless, broadened spectrum in the high energy region.
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Acetaminofen/química , Conformação Molecular , Espectrofotometria UltravioletaRESUMO
Novel inorganic-organic hybrid hollow nanospheres, acrylated SiO2 and SiO2@TiO2, were synthesized via a sol-gel polymerization, using crown-appended sugar gelator 1 as an organic template for the unique nanospherical structures in demand for a fast expanding area in nanomaterial research. In this work, hollow SiO2 nanospheres were obtained by a simple sol-gel method followed by calcination and rather rough TiO2 nanolayers were coated onto the highly dispersed surface of SiO2 nanospheres and further copolymerization of MPA on the surface of SiO2 and SiO2@TiO2 nanosphseres was successfully conducted. The morphological properties of those hollow nanospheres were characterized by TEM, SEM and powder-XRD. Furthermore, the physical and chemical properties of the synthesized nanocomposites were characterized by the analysis of EDX, FT-IR, TGA and ESCA.
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Resinas Acrílicas/química , Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Dióxido de Silício/química , Titânio/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Porosidade , Propriedades de SuperfícieRESUMO
Binding energies of different nitrile solvents and their utilization for CuCN formation were investigated through quantum chemical calculations. A pulsed laser ablation in liquid (PLAL) method for CuCN synthesis was developed herein. Initially, the interaction between the pulsed laser and the Cu-target generated Cu-ions and electrons at the point of contact. The laser beam also exhibited sufficient energy to dissociate the bonds of the respective solvents. In the case of acetonitrile, the oxidized Cu-ions bonded with CN- to produce CuCN with a cube-like surface structure. Other nitrile solvents generated spherically-shaped Cu@graphitic carbon (Cu@GC) nanoparticles. Thus, the production of CuCN was favorable only in acetonitrile due to the availability of the cyano group immediately after the fragmentation of acetonitrile (CH3+ and CN-) under PLAL. Conversely, propionitrile and butyronitrile released large amounts of hydrocarbons, which deposited on Cu NPs surface to form GC layers. Following the encapsulation of Cu NPs with carbon shells, further interaction with the cyano group was not possible. Subsequently, theoretical study on the binding energies of nitrile solvents was confirmed by highly correlated basic sets of B3LYP and MP2 which results were consistent with the experimental outcomes. The findings obtained herein could be utilized for the development of novel metal-polymer materials.
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Correction for 'Changes in macrocyclic aromaticity and formation of a charge-separated state by complexation of expanded porphyrin and C60' by Won-Young Cha et al., Chem. Commun., 2019, 55, 8301-8304, DOI: .
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Comparative experiments were conducted to determine the effects of various solvents (i.e., deionized water, methanol, ethanol, 1-propanol, butanol, ethylene glycol, hexane, and acetonitrile) on the final compositions, morphologies, and catalytic activities of copper-based nanoparticles (NPs). The NPs were effectively synthesized by pulsed laser ablation (PLA) using a copper plate as the target. The obtained copper NPs were characterized utilizing various analytical techniques. It was established that the developed methodology allows for the production of NPs with different morphologies and compositions in a safe and simple manner. When laser ablation of a solid copper plate was performed in acetonitrile, the formation of copper(I) cyanide cubes was observed. On the other hand, in deionized water and methanol, spherical and rod-like particles of copper(I) and copper(II) oxide were detected, respectively. The catalytic activity of the prepared copper NPs in the reduction of aromatic nitro compounds, such as 4-nitrophenol and nitrobenzene, was also evaluated. A high k value was determined for the reduction over the copper(II) oxide NPs produced in methanol. Moreover, particles with graphitic carbon (GC) layers exhibited superior catalytic performance in the reduction of a hydrophobic substance, i.e., nitrobenzene, over the reduction of 4-nitrophenol. The enhanced catalytic activity of this catalyst may be due its unique surface morphology and the synergistic effects between the copper nanostructure and the GC layer. Lastly, a detailed reduction pathway mechanism for the catalytic reduction of 4-nitrophenol and nitrobenzene has been proposed.
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Significant changes of macrocyclic aromaticity in expanded porphyrins through C60 complexation were studied by 1H NMR spectroscopy and nucleus-independent chemical shift calculations. This work is a detailed research study of how the formation of a complex of dual aromatic expanded porphyrin with fullerene affects the electron densities in the main conjugation pathways and meso-substituents. Furthermore, we found that the formation of the photoinduced charge-separated state and the triplet excited-state populations of the bowl-shaped and rigid expanded porphyrin can be controlled by a simple complexation with C60.
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Histidine, inspired by vanadium bromoperoxidase enzyme, has been applied as a homogeneous electrocatalyst to the positive electrolyte of vanadium redox flow battery (VRFB) to improve the performance and stability of VRFB at elevated temperatures. The histidine-containing electrolyte is found to significantly improve the performance of VRFB in terms of thermal stability estimated by the remaining amount of VO2+ in the electrolyte (61 vs 43% of a pristine one), energy efficiency at a high current density of 150 mA cm-2 (78.7 vs 71.2%), and capacity retention (73.2 vs 27.7%) at 60 °C. The mechanism of the catalytic functions of histidine with the chemical species in the electrolyte has been investigated for the first time by multinuclear NMR spectroscopy and first-principles calculations. The analyzed data reveal that histidine improves the kinetics of both charge and discharge reactions through different affinity toward the reactants and products as well as suppresses the precipitation of VO2+ by impeding the polymerization of vanadium ions. These findings are in good agreement with the improved chemical and electrochemical performance of the histidine-containing VRFB. Our results show a new type of chemical/electrochemical mechanism in the improved redox flow battery performance that may be essential in a new research arena for better performance of electrochemical systems.
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Fontes de Energia Elétrica , Eletrólitos/química , Oxirredução , Vanádio/química , Temperatura Alta , Peroxidases/químicaRESUMO
Congenital muscular torticollis (CMT) is known to concur with some conditions such as developmental dysplasia of the hip or brachial plexus injury, which gives us some insights for pathogenesis of CMT. Although clavicular fracture is the most common fracture in newborns, little is known about concurrence of CMT and clavicular fracture. Our clinical experience led us to realize that concurrence of CMT and clavicular fracture tended to occur on the contralateral side for each other rather than the ipsilateral side. This study aimed to verify contralateral concurrence of CMT and clavicular fracture. This is a retrospective cohort study in a tertiary hospital, including 996 subjects with CMT. Concurrent clavicular fracture was found in 20 of 996 subjects with CMT, with the concurrence rate being 2.01%. Concurrent clavicular fracture and clavicular fracture occurred on the contralateral side for each other in 18 subjects (90%) rather than the ipsilateral side. This contralateral concurrence between side of CMT and clavicular fracture was significant (P = 0.001), with an odds ratio of 81 (P = 0.0032). Concurrent clavicular fracture and clavicular fracture seem to occur significantly more on the contralateral side for each other. Underlying mechanism for consistent contralateral concurrence needs to be verified in the near future.
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Clavícula/lesões , Fraturas Ósseas/complicações , Torcicolo/congênito , Feminino , Fraturas Ósseas/congênito , Fraturas Ósseas/patologia , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Razão de Chances , Estudos Retrospectivos , Torcicolo/complicações , Torcicolo/patologiaRESUMO
Grisel syndrome is a rare, non-traumatic atlanto-axial subluxation associated with an inflammatory or infectious process in the upper neck. According to the two-hit hypothesis, which is widely accepted for the pathogenesis of Grisel syndrome, preexisting ligamentous laxity of the atlanto-axial joint is regarded as the first hit. An inflammatory or infectious process of the atlanto-axial joint acts as the second hit, resulting in non-traumatic atlanto-axial subluxation. We report on a 6-year-old girl with atlanto-axial subluxation following retropharyngeal and cervical lymphadenitis. She was diagnosed with Grisel syndrome, for which an initial computed tomography did not show any preexisting ligamentous laxity of the atlanto-axial joint. A literature review found only 4 case reports on Grisel syndrome with an initially normal atlanto-axial joint. The present case offers some evidence that a single hit, such as inflammatory changes in the atlanto-axial joint, might cause Grisel syndrome, even without underlying ligamentous laxity.
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OBJECTIVE: To identify the correlation between change in spinal deformities after surgical release and age at the time of surgery, and the effectiveness of surgical release in patients with neglected congenital muscular torticollis (CMT). METHODS: This was a retrospective study of 46 subjects with neglected CMT who had undergone surgical release at age ≥5 years at a tertiary medical center between January 2009 and January 2014. Spinal deformities were measured on anteroposterior plain radiographs of the cervical and whole spine, both preoperatively and postoperatively, to assess 3 parameters: cervicomandibular angle (CMA), lateral shift (LS), and Cobb angle (CA). We analyzed the change in spinal deformities after surgical release in consideration of age at the time of surgery. RESULTS: The median age at the time of surgery was 12.87 years. All 3 parameters showed significant improvement after surgical release (median values, pre- to post-surgery: CMA, 12.13° to 4.02°; LS, 18.13 mm to 13.55 mm; CA, 6.10° to 4.80°; all p<0.05). There was no significant correlation between age at the time of surgery and change in CMA (R=0.145, p=0.341) and LS (R=0.103, p=0.608). However, CA showed significant improvement with increasing age (R=0.150, p=0.046). CONCLUSION: We assessed the correlation between change in spinal deformities after surgical release and age at the time of surgery. We found that that surgical release is effective for spinal deformities, even in older patients. These findings enhance our understanding of the effectiveness and timing of surgical release in patients with neglected CMT.
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Spectroscopic techniques exist that may discern between enantiomers and assess chiral purity. A nonspectroscopic approach that may be directly observed could provide numerous benefits. Using chiral alanine-appended benzene-tricarboxamide gelators, we reveal a methanol gel system that is capable of providing visual discrimination between enantiomers of various diamines. Specifically, gelation is induced by supramolecular nanofiber assembly resulting from interaction between a chiral gelator and a diamine of opposing chirality (i.e., a heterochiral system). Upon further implementing the chiral gelator in electrospun fibers as solid state films, we revealed enantioselective surface wetting properties that allowed for determining chirality through contact angle measurements. While these two approaches of observable gelation and surface wetting offer nonspectroscopic approaches, we also find that the supramolecular nanofiber assembly was able to enhance the induced circular dichroism signal resulting from addition of chiral diamines, allowing precise quantification of their enantiomeric purity.
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Congenital muscular torticollis (CMT) and craniosynostosis are diseases that cause plagiocephaly and craniofacial asymmetry in children. In our literature review, we did not find any report of concurrent manifestation of CMT and craniosynostosis. A 41-month-old boy visited our hospital with left torticollis, right laterocollis, and craniofacial asymmetry as the main findings. During clinical examination, prominent right sternocleidomastoid muscle and limited range of motion of the neck were noted, and right CMT was confirmed by magnetic resonance imaging of the neck. Three-dimensional computed tomography of the skull, which was conducted due to the unusual appearance of the skull with a large head circumference, mild brachycephaly, as well as left plagiocephaly, revealed premature closure of the sagittal suture. Thus, we report the first case that showed concurrence of CMT and sagittal synostosis. We recommend that concurrently manifested craniosynostosis needs to be examined if the subject with CMT displays unusual craniofacial asymmetry to a greater extent than deformational plagiocephaly.