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Acute liver failure is an infrequent yet fatal condition marked by rapid liver function decline, leading to abnormalities in blood clotting and cognitive impairment among individuals without prior liver ailments. The primary reasons for liver failure are infection with hepatitis virus or overdose of certain medicines, such as acetaminophen. Phaeodactylum tricornutum (PT), a type of microalgae known as a diatom species, has been reported to contain an active ingredient with anti-inflammatory and anti-obesity effects. In this study, we evaluated the preventive and therapeutic activities of PT extract in acute liver failure. To achieve our purpose, we used two different acute liver failure models: acetaminophen- and D-GalN/LPS-induced acute liver failure. PT extract showed protective activity against acetaminophen-induced acute liver failure through attenuation of the inflammatory response. However, we failed to demonstrate the protective effects of PT against acute liver injury in the D-GalN/LPS model. Although the PT extract did not show protective activity against two different acute liver failure animal models, this study clearly demonstrates the importance of considering the differences among animal models when selecting an acute liver failure model for evaluation.
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Acetaminofén , Enfermedad Hepática Inducida por Sustancias y Drogas , Modelos Animales de Enfermedad , Microalgas , Animales , Acetaminofén/efectos adversos , Ratones , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Microalgas/química , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/tratamiento farmacológico , Masculino , Sustancias Protectoras/farmacología , Sustancias Protectoras/uso terapéutico , Etanol/efectos adversos , Diatomeas , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismo , Lipopolisacáridos/efectos adversosRESUMEN
Self-assembly of small amphiphilic molecules in water can lead to nanostructures of varying geometries with pristine internal molecular organization. Here we introduce a photoswitchable aramid amphiphile (AA), designed to exhibit extensive hydrogen bonding and robust mechanical properties upon self-assembly, while containing a vinylnitrile group for photoinduced cis-trans isomerization. We demonstrate spontaneous self-assembly of the vinylnitrile-containing AA in water to form nanoribbons. Upon UV irradiation, trans-to-cis isomerizations occur concomitantly with a morphological transition from nanoribbons to nanotubes. The nanotube structure persists in water for over six months, stabilized by strong and collective intermolecular interactions. We demonstrate that the nanoribbon-to-nanotube transition is reversible upon heating and that switching between states can be achieved repeatedly. Finally, we use electron microscopy to capture the transition and propose mechanisms for nanoribbon-to-nanotube rearrangement and vice versa. The stability and switchability of photoresponsive AA nanostructures make them viable for a range of future applications.
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Charge neutral, nonconjugated organic radicals have emerged as extremely useful active materials for solid-state electronic applications. This previous achievement confirmed the potential of radical-based macromolecules in organic electronic devices; however, charge transport in radical molecules has not been studied in great detail from a fundamental perspective. Here we demonstrate the charge transport in a nonconjugated organic small radical, 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (h-TEMPO). The chemical component of this radical molecule allows us to form a single crystal via physical vapor deposition (PVD). While the charge transport of this macroscopic open-shell single crystal is rather low, thermal annealing of the well-defined single crystal enables the molecule to have a rapid charge transfer reaction due to the electronic communication of open-shell sites with each other, which results in electrical conductivities greater than 0.05 S m-1. This effort demonstrates a drastically different model than the commonly accepted conjugated polymers or molecules for the creation of next-generation conductors.
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Since the molecular self-assembly of nanomaterials is sensitive to their surface properties, the molecular packing structure on the surface is essential to build the desired chemical and physical properties of nanomaterials. Here, a new nanosurfactant is proposed for the automatic construction of macroscopic surface alignment layer for liquid crystal (LC) molecules. An asymmetric nanosurfactant (C60 NS) consisted of mesogenic cyanobiphenyl moieties with flexible alkyl chains and a [60]fullerene nanoatom is newly designed and precisely synthesized. The C60 NS directly introduced in the anisotropic LC medium is self-assembled into the monolayered protrusions on the surface because of its amphiphilic nature originated by asymmetrically programmed structural motif of LC-favoring moieties and LC-repelling groups. The monolayered protrusions constructed by the phase-separation and self-assembly of asymmetric C60 NS nanosurfactant in the anisotropic LC media amplify and transfer the molecular orientational order from surface to bulk, and finally create the automatic vertical molecular alignment on the macroscopic length scale. The asymmetric C60 NS nanosurfactant and its self-assembly described herein can offer the direct guideline of interface engineering for the automatic molecular alignments.
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Supramolecular chirality in a binary mixture of achiral bent-core (BC) and achiral rodlike mesogens was observed. Three different nanosegregated mesophases were determined in the binary system, and meaningful changes in circular dichroism (CD) were detected near the phase-transition temperatures of the rodlike mesogens. The highest CD intensity in the binary system was noted in the nanosegregated mesophase, in which the BC mesogens were in the helical nanofilament (HNF) phase and the rodlike mesogens were in the smecticâ A phase. The supramolecular chirality in the binary mixture was attributed to the self-assembled hierarchical chiral superstructures. Based on the experimental results, plausible scenarios for the chiral superstructures of the rodlike molecules embedded in the HNF networks are suggested. In addition, a system comprising BC and rodlike molecules doped with a photoresponsive compound exhibited remarkable photoswitching of CD intensity. According to the isothermal photoinduced phase transition of the embedded molecules in BC molecular HNFs, the observed CD intensities can be dynamically and reversibly modulated. Such a material with easily controllable functionality is of considerable interest in the field of materials science.
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Herein, we have synthesized novel photopolymerizable dumbbell-shaped diacetylene liquid crystal (LC) monomers by locating a diacetylene dicarboxylic acid group at the center and chemically connecting swallow-tails, such as hydrophobic alkyl chains (abbreviated as AT3DI) and amphiphilic biphenyl mesogens (abbreviated as BP3DI), with bisamide groups. Major phase transitions of dumbbell-shaped diacetylene monomers were identified using differential scanning calorimetry (DSC), polarized optical microscopy (POM), and Fourier transform infrared spectroscopy (FT IR). Molecular packing structures were studied based on structure-sensitive wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) analyses. Mainly, due to nanophase separations and strong intermolecular hydrogen bonding, AT3DI formed a low-ordered lamellar LC phase at room temperature. BP3DI self-assembled into highly-ordered crystal phases (K1 and K2) at lower temperatures below a low-ordered lamellar LC phase, in which BP3DI were intercalated with each other to compensate the mutual volume differences. From the photopolymerization of AT3DI and BP3DI, it was realized that the topochemical reactions of dumbbell-shaped diacetylene monomers were closely related to their chemical structures as well as molecular packing structures.
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Erythromelalgia is often refractory and resistant to many forms of treatment. Numerous therapeutic options have been tried, but effective treatment remains elusive. The sympathetic nervous system has been involved in various painful conditions of neuropathic, vascular, and visceral origin. Sympathetic block is helpful in making a diagnosis and managing pain. We report a case of excellent pain relief after lumbar sympathetic pulsed radiofrequency treatment in a patient with primary erythromelalgia of the lower extremities. This case suggests the viability of pulsed radiofrequency treatment in patients with erythromelalgia.
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Eritromelalgia/terapia , Región Lumbosacra , Tratamiento de Radiofrecuencia Pulsada/métodos , Femenino , Fluoroscopía , Humanos , Dolor , Manejo del Dolor/métodos , Adulto JovenRESUMEN
PURPOSE: To explore the added value of histogram analysis of apparent diffusion coefficient (ADC) values over magnetic resonance (MR) imaging and fluorine 18 ((18)F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) for the detection of occult palatine tonsil squamous cell carcinoma (SCC) in patients with cervical nodal metastasis from a cancer of an unknown primary site. MATERIALS AND METHODS: The institutional review board approved this retrospective study, and the requirement for informed consent was waived. Differences in the bimodal histogram parameters of the ADC values were assessed among occult palatine tonsil SCC (n = 19), overt palatine tonsil SCC (n = 20), and normal palatine tonsils (n = 20). One-way analysis of variance was used to analyze differences among the three groups. Receiver operating characteristic curve analysis was used to determine the best differentiating parameters. The increased sensitivity of histogram analysis over MR imaging and (18)F-FDG PET/CT for the detection of occult palatine tonsil SCC was evaluated as added value. RESULTS: Histogram analysis showed statistically significant differences in the mean, standard deviation, and 50th and 90th percentile ADC values among the three groups (P < .0045). Occult palatine tonsil SCC had a significantly higher standard deviation for the overall curves, mean and standard deviation of the higher curves, and 90th percentile ADC value, compared with normal palatine tonsils (P < .0167). Receiver operating characteristic curve analysis showed that the standard deviation of the overall curve best delineated occult palatine tonsil SCC from normal palatine tonsils, with a sensitivity of 78.9% (15 of 19 patients) and a specificity of 60% (12 of 20 patients). The added value of ADC histogram analysis was 52.6% over MR imaging alone and 15.8% over combined conventional MR imaging and (18)F-FDG PET/CT. CONCLUSION: Adding ADC histogram analysis to conventional MR imaging can improve the detection sensitivity for occult palatine tonsil SCC in patients with a cervical nodal metastasis originating from a cancer of an unknown primary site.
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Imagen Multimodal , Neoplasias Primarias Desconocidas/diagnóstico , Neoplasias Tonsilares/diagnóstico , Adulto , Anciano , Biopsia , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Fluorodesoxiglucosa F18 , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Estudios Retrospectivos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/métodos , Neoplasias Tonsilares/cirugía , TonsilectomíaRESUMEN
OBJECTIVES: To determine the diagnostic superiority of parametric response mapping of apparent diffusion coefficient (ADCPR) for predicting glioblastoma treatment response, compared to single time point measurement. METHODS: Fifty post-treatment glioblastoma patients were enrolled. ADCPR was calculated from serial apparent diffusion coefficient (ADC) maps acquired before and at the time of first detection of an enlarged contrast-enhancing lesion on voxel-by-voxel basis. The percentage-decrease in ADCPR and tenth percentile histogram cutoff value of ADC (ADC10) were compared at subsequent 3-month and 1-year follow-ups. RESULTS: The percentage-decrease in ADCPR was significantly higher in the progression group (mean = 33.2-38.3 %) than in the stable-response group (mean = 9.7 %) at 3 months follow-up (corrected p < 0.001 for both readers). ADCPR significantly improved area under the receiver operating characteristic curve from 0.67 to 0.88 (corrected p = 0.037) and from 0.70 to 0.92 (corrected p = 0.020) for both readers, respectively, compared to ADC10 at 3-month follow-up, but did not significantly improve at 1-year follow-up. The inter-reader agreement was higher for ADCPR than ADC10 (intraclass correlation coefficient, 0.93 versus 0.86). CONCLUSION: Voxel-based ADCPR appears to be a superior imaging biomarker than ADC, particularly for predicting early tumour progression in patients with glioblastoma. KEY POINTS: ⢠Treatment response pattern of glioblastoma was evaluated using voxel-based ADCPR and ADC10. ⢠Voxel-based ADCPR was more accurate in predicting treatment response pattern than ADC10. ⢠Inter-reader agreement was higher in ADCPR calculation than in ADC10 calculation. ⢠Voxel-based ADCPR can be a predictor of early treatment response pattern for glioblastoma.
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Mapeo Encefálico/métodos , Neoplasias Encefálicas/patología , Glioblastoma/patología , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/terapia , Femenino , Estudios de Seguimiento , Glioblastoma/terapia , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Without the conventional polymer-based liquid crystal (LC) alignment process, a newly synthesized dual photo-functionalized amphiphile (abbreviated as ADMA1 ) was successfully applied as a robust photo-reversible LC alignment layer by self-assembly and photo-polymerization. The LC alignment layer constructed by directly adding dual photo-functionalized amphiphiles into LC media significantly cuts the manufacturing cost as well as opens new doors for the fabrication of novel electro-optical devices.
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The formation of optically isotropic liquid crystal (LC) media has been investigated by doping the star-shaped LC molecular surfactants (SiLC) into the rod-shaped twin LC host molecules (DiLC). The experimental phase diagram was constructed on the basis of differential scanning calorimetry (DSC) and then a theoretical calculation was conducted through a combined Flory-Huggins (FH)/Maier-Saupe-McMillan (MSM)/phase field (PF) model to account for the experimental results. The phase diagram of the SiLC/DiLC mixtures revealed the broad coexistence regions such as smectic A + crystal (SmA1 + Cr2), liquid + crystal (L1 + Cr2), and liquid + nematic (L1 + N2) at the intermediate composition along with the narrow single phase crystal (Cr2), smectic (SmA1), and nematic (N2) regions. The morphologies and structures of these coexistence regions were further confirmed by polarized optical microscopy (POM) and wide-angle X-ray diffraction (WAXD). At the 80/20 SiLC/DiLC composition, the optical anisotropy was induced under an alternating current (AC) electric field above its isotropization temperature. The formation of an optically isotropic LC medium in mixtures of the SiLC molecular surfactants and nematic LC host may allow us to develop new electro-optical devices.
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A photochromic chiral molecule with azobenzene mesogens and a (R)-configuration naphthyl moiety (abbreviated as NCA2M) was specifically designed and synthesized for the demonstration of chameleon-like color changes responding to multitudinous external stimuli, such as temperature, light and electric field. The basic phase transition behaviors of NCA2M were first studied by the combination of differential scanning calorimetry (DSC) and polarized optical microscopy (POM). Based on the structure-sensitive X-ray diffraction results obtained at different temperatures, it was comprehended that the NCA2M molecule exhibited the tilted version of highly ordered smectic crystal phase with 5.45 nm layer thickness. Chiral nematic (N*) liquid crystals (LC) with helical superstructures were formed by doping the NCA2M photochromic chiral molecule in an achiral nematic (N) LC medium. By controlling the helical pitch length of N*-LC with respect to temperature, light and electric field, the wavelength of selectively reflected light from the N* photonic crystal was finely tuned. The light-induced color change of N*-LC film was the most efficient method for covering the whole visible region from blue to green and to red, which allowed us to fabricate remote-controllable photo-responsive devices.
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Unconventional star-shaped liquid crystals (abbreviated as SiLCs) were successfully synthesized by chemically connecting four cyanobiphenyl anisotropic mesogens to the periphery of a super-hydrophobic and ultra-flexible cyclic tetramethyltetrasiloxane ring with flexible hexyl chains. Based on the combined experimental techniques of differential scanning calorimetry (DSC), cross-polarized optical microscopy (POM), solid-state carbon-13 ((13)C) nuclear magnetic resonance (NMR) spectroscopy and one-dimensional (1D) wide-angle X-ray diffraction (WAXD), it was found that the SiLC molecule exhibited the monotropic phase transition from a LC phase to a crystalline phase. The crystalline phase was only detected during slow heating processes above its glass transition temperature, while a LC phase was formed both during cooling and during heating processes. The hierarchical superstructures were identified from the structure-sensitive 2D WAXD of the macroscopically oriented SiLC film and confirmed by selected area electron diffraction (SAED) of the SiLC single crystals. The molecular packing symmetry in the monoclinic unit cell was further investigated by computer simulations on the real and reciprocal spaces. Macroscopically oriented SiLC hierarchical superstructures on the different length scales may provide the targeted physical properties, which can allow us to apply SiLC molecules in the fields of electro-optical devices and nonlinear optics.
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A ribbon-shaped chiral liquid crystalline (LC) dendrimer with photochromic azobenzene mesogens and an isosorbide chiral center (abbreviated as AZ3 DLC) was successfully synthesized and its major phase transitions were studied by using differential scanning calorimetry (DSC) and linear polarized optical microscopy (POM). Its ordered structures at different temperatures were further identified through structure-sensitive diffraction techniques. Based on the experimental results, it was found that the AZ3 DLC molecule exhibited the low-ordered chiral smectic (Sm*) LC phase with 6.31â nm periodicity at a high-temperature phase region. AZ3 DLC showed the reversible photoisomerization in both organic solvents and nematic (N) LC media. As a chiral-inducing agent, it exhibited a good solubility, a high helical-twisting power, and a large change in the helical-twisting power due to its photochemical isomerization in the commercially available N LC hosts. Therefore, we were able to reversibly "remote-control" the colors in the whole visible region by finely tuning the helical pitch of the spontaneously formed helical superstructures.
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Compuestos Azo/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Dendrímeros/química , Isosorbida/química , Cristales Líquidos/química , Rastreo Diferencial de Calorimetría , Modelos Moleculares , Transición de Fase , EstereoisomerismoRESUMEN
BACKGROUND: To evaluate the prognostic value of total tumor volume (TTV) in patients with laryngeal and hypopharyngeal carcinomas. METHODS: This study involved 182 patients with previously untreated advanced-stage squamous cell carcinoma of the larynx or hypopharynx. TTV were calculated from pretreatment contrast-enhanced computed tomography images. Univariate and multivariate analyses were used to identify factors associated with overall (OS), disease-specific (DSS), and disease-free survival (DFS). RESULTS: At a median follow-up of 63 months (range, 24-139 months), the 5 year OS, DSS, and DFS rates were 60.2%, 73.1%, and 69.4%, respectively. Multivariate analyses showed that tumor site was an independent predictor of DSS (P = 0.03); Charlson comorbidity index for OS (P = 0.001); second primary cancer for OS (P = 0.008) and DFS (P = 0.001); and vocal fold paralysis for DSS (P = 0.014) and DFS (P = 0.033). Extension to the tongue base was an independent predictor of OS (P = 0.007), DSS (P < 0.001), and DFS (P = 0.017), and TTV ≥8.38 ml was an independent predictor of all three survivals (P < 0.001 each). CONCLUSION: Radiologically determined TTV is prognostic of survival in patients with advanced-stage laryngeal and hypopharyngeal carcinoma.
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Carcinoma de Células Escamosas/patología , Neoplasias Hipofaríngeas/patología , Neoplasias Laríngeas/patología , Carga Tumoral , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Medios de Contraste , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hipofaríngeas/diagnóstico por imagen , Neoplasias Hipofaríngeas/radioterapia , Neoplasias Hipofaríngeas/cirugía , Estimación de Kaplan-Meier , Neoplasias Laríngeas/diagnóstico por imagen , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirugía , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Medición de Riesgo , Factores de Riesgo , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento , Parálisis de los Pliegues Vocales/etiologíaRESUMEN
The declining honeybee populations are a significant risk to the productivity and security of agriculture worldwide. Although there are many causes of these declines, parasites are a significant one. Disease glitches in honeybees have been identified in recent years and increasing attention has been paid to addressing the issue. Between 30% and 40% of all managed honeybee colonies in the USA have perished annually over the past few years. American foulbrood (AFB) and European foulbrood (EFB) have been reported as bacterial diseases, Nosema as a protozoan disease, and Chalkbrood and Stonebrood as fungal diseases. The study aims to compare the bacterial community related to the Nosema ceranae and Ascosphaera apis infection on the gut of the honeybee and compare it with the weakly active honeybees. The Nosema-infected honeybees contain the phyla Proteobacteria as the significantly dominant bacterial phyla, similar to the weakly active honeybees. In contrast, the Ascosphaera (Chalkbrood) infected honeybee contains large amounts of Firmicutes rather than Proteobacteria.
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Light manipulation strategies of nature have fascinated humans for centuries. In particular, structural colors are of considerable interest due to their ability to control the interaction between light and matter. Here, wrinkled photonic crystal papers (PCPs) are fabricated to demonstrate the consistent reflection of colors regardless of viewing angles. The nanoscale molecular self-assembly of a cholesteric liquid crystal (CLC) with a microscale corrugated surface is combined. Fully polymerizable CLC paints are uniaxially coated onto a wrinkled interpenetrating polymer network (IPN) substrate. Photopolymerization of the helicoidal nanostructures results in a flexible and free-standing PCP. The facile method of fabricating the wrinkled PCPs provides a scalable route for the development of novel chirophotonic materials with precisely controlled helical pitch and curvature dimensions. The reflection notch position of the flat PCP shifts to a lower wavelength when the viewing angle increased, while the selective reflection wavelength of wrinkled PCP is remained consistent regardless of viewing angles. The optical reflection of the 1D stripe-wrinkled PCP is dependent on the wrinkle direction. PCPs with different corrugated directions can be patterned to reduce the angular-dependent optical reflection of wrinkles. Furthermore, 2D wavy-wrinkled PCP is successfully developed that exhibit directionally independent reflection of color.
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Developmental venous anomalies (DVAs) are common intracranial vascular malformations and they are generally do not cause clinical complications. In cases showing DVA and hemorrhage, the hemorrhage is usually associated with adjacent cavernous malformations. Very few cases of intracerebral hemorrhage (ICH) caused by thrombosis in DVA have been reported in the literature. In this case report, we present an interesting case of a large ICH caused by thrombosis within a DVA with an unusual structure that may have potentiated the thrombosis.
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Meningiomas are the most common intracranial tumors. However, microcystic and angiomatous meningiomas are very rare subtypes that present unusual imaging findings. Hence, radiological diagnosis of these tumors can be challenging. We herein describe a case of mixed angiomatous and microcystic meningioma in an 81-year-old male. MRI revealed an extra-axial mass with high T2 signal intensity, measuring 1.5 cm in diameter, with multiple tiny intralesional cysts and entrapped peritumoral cyst formation. After tumor resection, a histopathological diagnosis of mixed angiomatous and microcystic meningioma was made.
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Individual carbon nanotubes (CNT) and graphene have unique mechanical and electrical properties; however, the properties of their macroscopic assemblies have not met expectations because of limited physical dimensions, the limited degree of dispersion of the components, and various structural defects. Here, a state-of-the-art assembly for a novel type of hybrid fiber possessing the properties required for a wide variety of multifunctional applications is presented. A simple and effective multidimensional nanostructure of CNT and graphene oxide (GO) assembled by solution processing improves the interfacial utilization of the components. Flexible GOs are effectively intercalated between nanotubes along the shape of CNTs, which reduces voids, enhances orientation, and maximizes the contact between elements. The microstructure is finely controlled by the elements content ratio and dimensions, and an optimal balance improves the mechanical properties. The hybrid fibers simultaneously exhibit exceptional strength (6.05 GPa), modulus (422 GPa), toughness (76.8 J g-1 ), electrical conductivity (8.43 MS m-1 ), and knot strength efficiency (92%). Furthermore, surface and electrochemical properties are significantly improved by tuning the GO content, further expanding the scope of applications. These hybrid fibers are expected to offer a strategy for overcoming the limitations of existing fibers in meeting the requirements for applications in the fiber industry.