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Novel two-dimensional semiconductor crystals can exhibit diverse physical properties beyond their inherent semiconducting attributes, making their pursuit paramount. Memristive properties, as exemplars of these attributes, are predominantly manifested in wide-bandgap materials. However, simultaneously harnessing semiconductor properties alongside memristive characteristics to produce memtransistors is challenging. Herein we prepared a class of semiconducting III-V-derived van der Waals crystals, specifically the HxA1-xBX form, exhibiting memristive characteristics. To identify candidates for the material synthesis, we conducted a systematic high-throughput screening, leading us to 44 prospective III-V candidates; of these, we successfully synthesized ten, including nitrides, phosphides, arsenides and antimonides. These materials exhibited intriguing characteristics such as electrochemical polarization and memristive phenomena while retaining their semiconductive attributes. We demonstrated the gate-tunable synaptic and logic functions within single-gate memtransistors, capitalizing on the synergistic interplay between the semiconducting and memristive properties of our two-dimensional crystals. Our approach guides the discovery of van der Waals materials with unique properties from unconventional crystal symmetries.
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Dysregulated Wnt signaling is associated with malignant oncogenic transformation, especially in colon cancer. Recently, numerous drugs have been developed based on tumorigenesis biomarkers, thus having high potential as drug targets. Likewise, WNT/ß-catenin pathway members are attractive therapeutic targets for colon cancer and are currently in various stages of development. However, although inhibitors of proteins regulating the WNT/ß-catenin signaling pathway have been extensively studied, they have yet to be clinically approved, and the underlying molecular mechanism(s) of their anticancer effects remain poorly understood. Herein, we show that a novel WNT/ß-catenin inhibitor, DGG-300273, inhibits colon cancer cell growth in a Wnt-dependent manner due to upregulation of the BCL2-family protein Bim and caspase-dependent apoptotic cell death. Additionally, DGG-300273-mediated cell death occurs by increased reactive oxygen species (ROS), as shown by abrogation of apoptotic cell death and ROS production following pretreatment with the antioxidant N-acetylcysteine. These results suggest that DGG-300273 represents a promising investigational drug for the treatment of Wnt-associated cancer, thus warranting further characterization and study.
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Neoplasias do Colo , beta Catenina , Humanos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Via de Sinalização WntRESUMO
Aluminum nitride, with its high thermal conductivity and insulating properties, is a promising candidate as a thermal dissipation material in optoelectronics and high-power logic devices. In this work, we have shown that the thermal conductivity and electrical resistivity of AlN ceramics are primarily governed by ionic defects created by oxygen dissolved in AlN grains, which are directly probed using 27Al NMR spectroscopy. We find that a 4-coordinated AlN3O defect (ON) in the AlN lattice is changed to intermediate AlNO3, and further to 6-coordinated AlO6 with decreasing oxygen concentration. As the aluminum vacancy (VAl) defect, which is detrimental to thermal conductivity, is removed, the overall thermal conductivity is improved from 120 to 160 W/mK because of the relatively minor effect of the AlO6 defect on thermal conductivity. With the same total oxygen content, as the AlN3O defect concentration decreases, thermal conductivity increases. The electrical resistivity of our AlN ceramics also increases with the removal of oxygen because the major ionic carrier is VAl. Our results show that to enhance the thermal conductivity and electrical resistivity of AlN ceramics, the dissolved oxygen in AlN grains should be removed first. This understanding of the local structure of Al-related defects enables us to design new thermal dissipation materials.
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Cancer cells are characterized by an abnormal cell cycle. Therefore, the cell cycle has been a potential target for cancer therapeutic agents. We developed a new lead compound, DGG200064 (7c) with a 2-alkoxythieno [2,3-b]pyrazine-3-yl)-4-arylpiperazine-1-carboxamide core skeleton. To evaluate its properties, compound DGG200064 was tested in vivo through a xenograft mouse model of colorectal cancer using HCT116 cells. The in vivo results showed high cell growth inhibition efficacy. Our results confirmed that the newly synthesized DGG200064 inhibits the growth of colorectal cancer cells by inducing G2/M arrest. Unlike the known cell cycle inhibitors, DGG200064 (GI50 = 12 nM in an HCT116 cell-based assay) induced G2/M arrest by selectively inhibiting the interaction of FBXW7 and c-Jun proteins. Additionally, the physicochemical properties of the lead compounds were analyzed. Based on the results of the study, we suggested further development of DGG200064 as a novel oral anti-colorectal cancer drug.
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Extraordinary properties of traditional hyperbolic metamaterials, not found in nature, arise from their man-made subwavelength structures causing unique light-matter interactions. However, their preparation requiring nanofabrication processes is highly challenging and merely provides nanoscale two-dimensional structures. Stabilizing their bulk forms via scalable procedures has been a sought-goal for broad applications of this technology. Herein, we report a new strategy of designing and realizing bulk metamaterials with finely tunable hyperbolic responses. We develop a facile two-step process: (1) self-assembly to obtain heterostructured nanohybrids of building blocks and (2) consolidation to convert nanohybrid powders to dense bulk pellets. Our samples have centimeter-scale dimensions typically, readily further scalable. Importantly, the thickness of building blocks and their relative concentration in bulk materials serve as a delicate means of controlling hyperbolic responses. The resulting new bulk heterostructured material system consists of the alternating h-BN and graphite/graphene nanolayers and exhibits significant modulation in both type-I and type-II hyperbolic resonance modes. It is the first example of real bulk hyperbolic metamaterials, consequently displaying the capability of tuning their responses along both in-plane and out-of-plane directions of the materials for the first time. It also distinctly interacts with unpolarized and polarized transverse magnetic and electronic beams to give unique hyperbolic responses. Our achievement can be a new platform to create various bulk metamaterials without complicated nanofabrication techniques. Our facile synthesis method using common laboratory techniques can open doors to broad-range researchers for active interdisciplinary studies for this otherwise hardly accessible technology.
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This study presents an anticipatory integrated education program for nausea, vomiting, and dizziness prevention (anti-NVD education program) for patients undergoing abdominal surgery under general anesthesia. The anti-NVD education program for nephrectomy patients consisted of the following: the causes of postoperative nausea, vomiting, and dizziness; effective deep breathing and how to use an inspirometer; postoperative nausea and vomiting; effective methods of patient-controlled analgesia; and the stepwise standing up method to prevent dizziness. A study was conducted among 79 adults (experimental group: n = 40, control group: n = 39). The degree of nausea and dizziness was measured using a numerical rating scale (NRS), and vomiting and the frequency of antiemetic use were measured in terms of the number of patients. The experimental group, which received the anti-NVD education, showed remarkably lower levels of nausea (p = 0.013) and dizziness (p < 0.001) than the control group. The frequency of antiemetic use 48 hours after surgery was significantly lower in the experimental group (p = 0.03). This study proved the efficacy of the anti-NVD education program for reducing postoperative nausea and dizziness. This program can be used as a noninvasive nursing intervention to prevent nausea, vomiting, and dizziness among patients undergoing abdominal surgery.
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Antieméticos , Náusea e Vômito Pós-Operatórios , Adulto , Analgesia Controlada pelo Paciente , Anestesia Geral/efeitos adversos , Antieméticos/uso terapêutico , Tontura/etiologia , Tontura/prevenção & controle , Método Duplo-Cego , Humanos , Náusea e Vômito Pós-Operatórios/prevenção & controleRESUMO
The prevalence of varicella is especially high among children in the age group of 4-6 years in South Korea, regardless of vaccination. We investigated the immune status of healthy children enrolled in day-care centers and compared pre- and post-vaccination immunity. Antibody titers were measured using a glycoprotein enzyme-linked immunosorbent assay (gpEIA) kit, and the seroconversion rate was assessed using a fluorescent antibody to membrane antigen (FAMA) test. Among 541 vaccinated children, 109 (20.1%) had breakthrough varicella. However, 13 (72.2%) of the 18 unvaccinated children had a history of varicella. The gpEIA geometric mean titers (GMTs) of pre- and 5 weeks post-vaccination in 1-year-old children were 14.7 and 72 mIU/mL, respectively, and the FAMA seroconversion rate was 91.1%. The gpEIA GMTs of 2-, 3-, 4-, 5-, and 6-year-old children were 104.1, 133.8, 223.5, 364.1, and 353.0 mIU/mL, respectively. Even though the gpEIA GMT increased with age, the pattern of gpEIA titer distribution in 4- to 6-year-old vaccinees without varicella history represented both waning immunity and natural boosting immunity. These results suggest that some vaccinees are vulnerable to varicella infection. Therefore, it is necessary to consider a two-dose varicella vaccine regimen in South Korea.
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Mung bean starch (MBS)-based edible films with incorporation of guar gum (GG) and sunflower seed oil (SSO) were developed in this study. MBS, GG, and SSO were used as the main filmogenic biopolymer, thickener, and hydrophobicity-imparting substance, respectively. To investigate the effect of SSO content on the physicochemical, mechanical, and optical properties of the films, they were supplemented with various concentrations (0, 0.5, 1, and 2%, w/w) of SSO. Increasing SSO content tended to decrease tensile strength, elongation at break, crystallinity, water solubility, and the water vapor permeability; in contrast, it increased the oxygen transmission rate and water contact angle. Consequently, the incorporation of SSO into the matrix of MBS-based films decreased their mechanical strength but effectively enhanced their water-resistance properties. Therefore, the MBS-based film developed here can be properly used as an edible film in settings that require high water-resistance properties but do not call for robust mechanical strength.
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Antimicrobial starch/gum-based edible emulsion coatings were developed to improve the storage stability of rice cakes by retarding starch retrogradation and inhibiting microbial growth. Rice cakes were coated with mung bean starch (MBS) and guar gum (GG) containing various concentrations of sunflower seed oil (SO). Among these, the (2 g MBS +0.75 g GG +1.5 g SO) / 100 g (optimum) decreased the hardness of rice cakes by 29 % and the crystallization rate (k) by 24 % compared with those of uncoated samples. The moisture loss in uncoated samples was markedly higher than that in the optimum blend-coated samples. Crystallinity analysis revealed the retarding effect of the developed coatings in starch retrogradation. Furthermore, adding 0.8 % (w/w) grapefruit seed extract to the optimum blend led to a distinct antimicrobial activity. Therefore, the newly developed edible coating was effective in maintaining the quality and safety of rice cakes.
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Anti-Infecciosos/química , Emulsões/química , Inocuidade dos Alimentos/métodos , Galactanos/química , Mananas/química , Gomas Vegetais/química , Amido/química , Vigna/química , Anti-Infecciosos/farmacologia , Bacillus cereus/efeitos dos fármacos , Bacillus cereus/crescimento & desenvolvimento , Varredura Diferencial de Calorimetria , Filmes Comestíveis , Emulsões/farmacologia , Conservação de Alimentos/métodos , Galactanos/farmacologia , Dureza , Cinética , Mananas/farmacologia , Microscopia Eletrônica de Varredura , Oryza/química , Oryza/metabolismo , Penicillium/efeitos dos fármacos , Penicillium/crescimento & desenvolvimento , Gomas Vegetais/farmacologia , Sementes/química , Amido/farmacologia , Óleo de Girassol/química , Água/análise , Água/química , Difração de Raios XRESUMO
This study aimed to explore the psychophysical bases of multisensory surface stickiness perception by investigating how sensitively humans perceive different levels of stickiness intensity conveyed by auditory, tactile, and visual cues. First, we sorted five different sticky stimuli by perceived intensity in ascending order for each modality separately and evaluated the discrimination sensitivities of each participant using a fitted psychometric curve. Results showed that perceptual intensity orders were not identical to physical intensity order and that the sequential order of perceived intensities for different modalities was inconsistent. Moreover, estimated perceptual sensitivities to surface stickiness indicated that auditory cues result in better discrimination sensitivity than tactile and visual cues. Second, we calculated the relative perceptual distances of stickiness intensities using multidimensional scaling. A follow-up statistical test demonstrated that the perceptual mapping of vision and touch are similar but that auditory perception is different. These results suggest that the discriminability of stickiness intensity is best served by auditory cues and that texture information processing in the auditory domain is distinctive from that of other modalities.
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A nonferrous oxygen scavenger (NFOS) comprising activated carbon and sodium l-ascorbate was developed to enhance the preservative efficacy of raw meatloaves. To determine the optimum formulation of activated carbon and sodium l-ascorbate, NFOSs with varying ratios of components (1:1, 1:1.2, 1:1.4, 1:1.6, 1:1.8, and 1:2, w/w) were prepared and their oxygen-scavenging volumes were measured over 4 d at 25 °C. Assays of oxygen-scavenging capacities indicated that the optimum NFOS formulation of activated carbon and sodium l-ascorbate was achieved at a ratio of 1:1.6 (w/w). Finally, the optimal NFOS sachet was applied to packaging of raw meatloaves and its oxygen-scavenging capacity was periodically analyzed. Moreover, microbiological changes (including total aerobic bacteria, lactic acid bacteria, and yeasts and molds) and an effect on lipid oxidation during the storage were examined at 4 °C for 4 d. The meatloaves packaged with NFOS sachet had lower thiobarbituric acid reactive substances and microbiological changes than control meatloaves, indicating the practical utility in the food packaging industry. PRACTICAL APPLICATION: Oxygen-scavenging sachets containing iron powder have been generally used although those have several problems. Therefore, to solve them, an ascorbic acid-based oxygen scavenger composed of activated carbon and sodium l-ascorbate was newly developed. It did not only inhibit lipid oxidation but also reduce microbial growth in meatloaves. It could be used as a promising packaging material to protect meat products from lipid oxidation and microbial contamination.
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Ácido Ascórbico , Embalagem de Alimentos/métodos , Sequestradores de Radicais Livres/química , Produtos da Carne , Espécies Reativas de Oxigênio/química , Animais , Carbono/química , Embalagem de Alimentos/instrumentação , Conservação de Alimentos/métodos , Peroxidação de Lipídeos , Carne/análise , Produtos da Carne/análise , Produtos da Carne/microbiologia , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
BACKGROUND: We previously reported that two-phase partition chromatography between ginseng water extract and soybean oil efficiently eliminated pesticide residues. However, an undesirable odor and an unpalatable taste unique to soybean oil were two major disadvantages of the method. This study was carried out to find an alternative vegetable oil that is cost effective, labor effective, and efficient without leaving an undesirable taste and smell. METHODS: We employed six vegetable oils that were available at a grocery store. A 1-mL sample of the corresponding oil containing a total of 32 pesticides, representing four categories, was mixed with 10% aqueous ginseng extract (20 mL) and equivalent vegetable oil (7 mL) in Falcon tubes. The final concentration of the pesticides in the mixture (28 mL) was adjusted to approximately 2 ppm. In addition, pesticides for spiking were clustered depending on the analytical equipment (GC/HPLC), detection mode (electron capture detector/nitrogen-phosphorus detector), or retention time used. Samples were harvested and subjected to quantitative analysis of the pesticides. RESULTS: Soybean oil demonstrated the highest efficiency in partitioning pesticide residues in the ginseng extract to the oil phase. However, canola oil gave the best result in an organoleptic test due to the lack of undesirable odor and unpalatable taste. Furthermore, the qualitative and quantitative changes of ginsenosides evaluated by TLC and HPLC, respectively, revealed no notable change before or after canola oil treatment. CONCLUSION: We suggest that canola oil is an excellent vehicle with respect to its organoleptic property, cost-effectiveness and efficiency of eliminating pesticide residues in ginseng extract.
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PURPOSE: To evaluate a recently marketed commercial glycoprotein enzyme-linked immunosorbent assay (gpEIA) kit, the VaccZyme™ VZV gpEIA, for measuring the immunity of varicella-vaccinated children. MATERIALS AND METHODS: We investigated the accuracy and reproducibility of the VaccZyme™ VZV gpEIA kit for the detection of antibodies to VZV. We also examined the sensitivity, specificity, and correlation between antibody titers calculated with gpEIA versus fluorescent antibody to membrane antigen (FAMA) by using sera of 349 children, ranging from 1 to 6 years old. RESULTS: VaccZyme™ VZV gpEIA gave precise and reproducible intra- and inter-assay results. FAMA and gpEIA titers showed a linear correlation (Pearson correlation coefficient=0.987). The sensitivity and specificity of the VaccZyme™ gpEIA was 31.4% and 100%, respectively, when the guidelines of the gpEIA (<100 mIU/mL) and FAMA 1:4 were adopted as cutoff values. However, the maximum sensitivity and specificity were 88.9% and 95.1%, respectively, with the highest correlation (κ=0.840), if the cutoff values were set with gpEIA at 49.7 mIU/mL and FAMA 1:16. CONCLUSION: These results demonstrate that the VaccZyme™ VZV gpEIA kit gave precise and reproducible data for measuring antibody titer after varicella vaccination. The results also showed that the antibody titer calculated with the VaccZyme™ gpEIA kit strongly correlated with the FAMA titer. However, cutoff values should be re-optimized for the evaluation of vaccine immunity.
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Anticorpos Antivirais/sangue , Varicela/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Vacinas Virais/imunologia , Criança , Pré-Escolar , Glicoproteínas/imunologia , Herpesvirus Humano 3/imunologia , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Oxygen plays an important role in the metabolism of alcohol. An increased dissolved oxygen level in alcoholic beverages reportedly accelerates the elimination of alcohol. Therefore, we evaluated the effect of dissolved oxygen in alcohol and the supportive effect of oxygenated water on alcohol pharmacokinetics after the excessive consumption of alcohol, i.e., 540 ml of 19.5% alcohol (v/v). Fifteen healthy males were included in this randomized, 3 × 3 crossover study. Three combinations were tested: X, normal alcoholic beverage and normal water; Y, oxygenated alcoholic beverage and normal water; Z, oxygenated alcoholic beverage and oxygenated water. Blood alcohol concentrations (BACs) were determined by conversion of breath alcohol concentrations. Four pharmacokinetic parameters (C(max), T(max), K(el), and AUCall) were obtained using non-compartmental analysis and the times to reach 0.05% and 0.03% BAC (T(0.05%) and T(0.03%)) were compared using one-way analysis of variance (ANOVA) and Duncan's post hoc test. With combination Z, the BAC decreased to 0.05% significantly faster (p < 0.05) than with combination X. Analyzing the pharmacokinetic parameters, the mean K(el) was significantly higher for combination Z than for combinations X and Y (p < 0.05), whereas the mean values of C(max), T(max) and AUCall did not differ significantly among the combinations. Dissolved oxygen in drinks accelerates the decrease in BAC after consuming a large amount of alcohol. However, the oxygen dissolved in the alcoholic beverage alone did not have a sufficient effect in this case. We postulate that highly oxygenated water augments the effect of oxygen in the alcoholic beverage in alcohol elimination. Therefore, it is necessary to investigate the supportive effect of ingesting additional oxygenated water after heavy drinking of normal alcoholic beverages.
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Consumo de Bebidas Alcoólicas/sangue , Bebidas Alcoólicas , Etanol/farmacocinética , Oxigênio/farmacologia , Adulto , Água Potável , Etanol/sangue , Etanol/metabolismo , Humanos , Masculino , Água/farmacologiaRESUMO
BACKGROUND: Widespread white matter (WM) pathology in preterm children has been proposed. OBJECTIVE: The purpose of this study was to investigate maturational differences of WM between preterm infants with thinning of the corpus callosum and full-term infants. MATERIALS AND METHODS: A total of 18 preterm children and 18 full-term children were divided into three subgroups according to the corrected age at the time of diffusion tensor imaging scanning. Tract-based spatial statistics was used for assessing differences in fractional anisotropy (FA) between preterm and full-term children, and between each age-related subgroup in preterm and in full-term children. RESULTS: In the preterm group, FA values of overall WM showed an increase with age. This trend indicates that WM maturation is a gradual occurrence during a child's first 2 years. In the full-term group, most WM structures had reached maturation at around 1 year of age; however, centrum semiovale level showed sustained maturation during the first 2 years. CONCLUSION: Results of our study demonstrate radiologic maturational differences of WM and provide evidence of the need for therapeutic intervention within 2 years of birth to prevent specific functional impairment and to improve clinical outcome in preterm children.
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Envelhecimento/patologia , Corpo Caloso/patologia , Fibras Nervosas Mielinizadas/patologia , Nascimento Prematuro/patologia , Nascimento a Termo , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Tumors of the central nervous system are common in the pediatric population and constitute the second most prevalent tumor type in children. Within this group, spinal cord tumors are relatively rare and account for 1 to 10% of all pediatric central nervous system tumors. We describe a very rare case of an intradural extramedullary spinal cord tumor with a subcutaneous mass and discuss its clinical presentation, pathogenesis, and treatment. A male infant was delivered normally, with uneventful development. At 16 days post-delivery, his family took him to a pediatrician because of a mass on his upper back. Magnetic resonance imaging of the thoracic spine revealed a well-demarcated soft-tissue mass with central cystic change or necrosis at the subcutaneous layer of the posterior back (T2-7 level). Another mass was found with a fat component at the spinal canal of the T1-3 level, which was intradural extramedullary space. After six weeks, the spinal cord tumor and subcutaneous mass were grossly total resected; pathologic findings indicated an atypical myxoid spindle cell neoplasm, possibly nerve sheath in type. The final diagnosis of the mass was an atypical myxoid spindle cell neoplasm. The postoperative course was uneventful, and the patient was discharged after nine days without any neurological deficit. We report a rare case of an intradural extramedullary spinal tumor with subcutaneous mass in a neonate. It is necessary to monitor the patient's status by examining consecutive radiologic images, and the symptoms and neurological changes should be observed strictly during long-term follow-up.
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Congenital chloride diarrhea (CLD) is an autosomal recessive disorder with the hallmark of persistent watery Cl(-)-rich diarrhea from birth. Mutations in the solute carrier family 26, member 3 (SLC26A3) gene, which encodes a coupled Cl(-)/HCO(3)(-) exchanger in the ileum and colon, are known to cause CLD. Although there are a few reports of CLD patients in Korea, none of these had been confirmed by genetic analysis. Here, we describe the case of a Korean infant with clinical features of CLD. Using direct sequencing analysis, we identified 2 sequence variants: a missense variant of unknown significance (c.525G>C; p.Arg175 Ser) and a splicing mutation (c.2063-1G>T) in the SLC26A3 gene; these had been inherited from the father and mother, respectively. Whilst CLD is rare, its main symptom, diarrhea, is very common in infants. Hence, the diagnosis of CLD can prove difficult. Mutational analysis of the SLC26A3 gene should be considered as a viable method to confirm a diagnosis of CLD in Korean infants with persistent diarrhea.
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Povo Asiático/genética , Antiportadores de Cloreto-Bicarbonato/genética , Diarreia/congênito , Erros Inatos do Metabolismo/diagnóstico , Análise Mutacional de DNA , Diarreia/diagnóstico , Diarreia/diagnóstico por imagem , Diarreia/genética , Heterozigoto , Humanos , Lactente , Masculino , Erros Inatos do Metabolismo/diagnóstico por imagem , Erros Inatos do Metabolismo/genética , Mutação , Mutação de Sentido Incorreto , Splicing de RNA , Radiografia , República da Coreia , Transportadores de Sulfato , Ultrassonografia Pré-NatalRESUMO
To investigate corticospinal tract (CST) status using diffusion tensor imaging (DTI) in patients who had clinical symptom of torticollis but no definite cause of sustained symptom of torticollis. We evaluated 10 patients with sustained torticollis and 12 age-matched control subjects. All patients showed no specific fibromatosis coli findings on neck sonography. Even after intensive manual therapy, there was no improvement of clinical symptom of torticollis. DTI was performed using 1.5 T with a synergy-L Sensitivity Encoding (SENSE) head coil. Fractional anisotropy and apparent diffusion coefficient were measured using the region of interest method, and diffusion tensor tractography was conducted. We estimated the asymmetric anisotropic index (AA) and asymmetric mean diffusivity index (AD) to evaluate the asymmetry between right and left CSTs. All patients showed only torticollis symptom but no definite hemiplegic pattern on their extremities at initial evaluation. DTT, which was performed to reveal the reason of sustained asymmetric postural symptom showed hemiplegic pattern. The results of DTT corresponded to the delayed hemiplegic symptoms, which were found in the patients at second evaluation. AA and AD values between patients and control group were significantly different. Torticollis is usually caused by fibromatosis coli, but may be one of the symptoms of hemiplegia. DTI may be an additional technique for the early detection of hemiplegia in patients with sustained symptoms of unexplainable postural torticollis.
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Torcicolo/diagnóstico , Anisotropia , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Hemiplegia/diagnóstico , Hemiplegia/etiologia , Hemiplegia/patologia , Humanos , Lactente , Masculino , Tratos Piramidais/lesões , Tratos Piramidais/patologia , Torcicolo/etiologia , Torcicolo/patologiaRESUMO
INTRODUCTION: Preterm children with thinning of the corpus callosum (CC) frequently achieve poor neurodevelopmental outcomes despite the absence of a definite brain lesion. Here, the authors compared the microstructural characteristics of the CC in preterm and full-term children using diffusion tensor imaging (DTI). METHODS: Twenty-two preterm children with no definite focal lesion but with thinning of the CC by conventional magnetic resonance imaging and 23 age-matched full-term children were investigated by DTI. CCs were subdivided into genu, rostral body, body, isthmus, and splenium, and voxel counts (VC), fractional anisotropies (FA), and apparent diffusion coefficients (ADC) were measured in each subdivision. Eleven preterm and 11 age-matched full-term subjects underwent follow-up scanning and interval changes in these parameters for each subdivision were compared. RESULTS: VC and FA were significantly lower in the preterm group than in the full-term group, particularly in the isthmus. Furthermore, incremental changes in VC and FA were significantly smaller in the preterm group. Differences in maturation between the two groups were more pronounced with age in all subdivisions except the splenium. At all ages, noticeable FA differences between the two groups were observed in the isthmus. For white matter tracts, the preterm group displayed lower FA and fiber number, higher ADC values than the term group. CONCLUSIONS: The present study shows that thinning of the CC is correlated with lower FA value and that it is more pronounced in preterm children. In addition, the isthmus was found to be the most vulnerable subdivision in preterm children.
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Corpo Caloso/patologia , Imagem de Tensor de Difusão/métodos , Recém-Nascido Prematuro , Análise de Variância , Criança , Pré-Escolar , Corpo Caloso/crescimento & desenvolvimento , Feminino , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
OBJECTIVES: Using diffusion tensor imaging (DTI), we investigated the state of medial lemniscus (ML), corticospinal tract (CST), and posterior thalamic radiation (PTR), which were expected as probable reasons for clinical hemiplegia in pediatric patients, especially those who showed impaired fine motor control and proprioception, but no definite motor weakness or spasticity. METHODS: We recruited 13 hemiplegic patients and 8 age-matched healthy control subjects. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) for the bilateral ML, CST, and PTR were calculated and compared between the affected hemisphere of the patient (AP), the unaffected hemisphere of the patient (UP), and the mean value of the bilateral hemispheres in control subjects (MC). RESULTS: FA and ADC values for the CST and PTR did not differ significantly between the AP, UP, and MC subgroups (p > 0.05). However, the FA value for the ML in AP showed a significant decrease, compared with that in UP (p = 0.012) and MC (p = 0.047). DTT for the CST and PTR showed preserved integrity and ML in the UP also had continuity to the cortex; however, ML in AP showed disruption. CONCLUSIONS: Using DTI, we demonstrated that the ML lesion might be related to clinical hemiplegia in pediatric patients.