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1.
Adv Mater ; : e2401131, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850153

RESUMO

Despite the commonality of static holograms, the holography with multiple information layers and reconfigurable grey-scale images at communication frequencies remain a confluence of scientific challenges. One well-known difficulty is the simultaneous modulation of phase and amplitude of electromagnetic wavefronts with a high modulation depth. A less appreciated challenge is scrambling of the information and images with hologram bending. Here, this work shows that chirality-guided pixelation of plasmonic kirigami sheets enables tunable multiplexed holography at terahertz (THz) frequencies. The convex and concave structures with slanted Au strips exhibit gradual variations in geometries facilitating modulation of light ellipticity reaching 40 deg. Real-time switching of 3D images of the letter "M" and the Mona Lisa demonstrates the possibility of complex grey-scale information content and importance of continuously variable mirror asymmetry. Microscale chirality measures of each pixel experiences little change with bending while retaining controllable reconfigurability upon stretching, which translates to remarkable resilience of chiral holograms to bending. Simplicity of their design with local chirality measures opens the door to information technologies with fault-tolerant THz encryption, wearable holographic devices, and new communication technologies.

2.
Nat Commun ; 15(1): 3071, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594231

RESUMO

Nanophase mixtures, leveraging the complementary strengths of each component, are vital for composites to overcome limitations posed by single elemental materials. Among these, metal-elastomer nanophases are particularly important, holding various practical applications for stretchable electronics. However, the methodology and understanding of nanophase mixing metals and elastomers are limited due to difficulties in blending caused by thermodynamic incompatibility. Here, we present a controlled method using kinetics to mix metal atoms with elastomeric chains on the nanoscale. We find that the chain migration flux and metal deposition rate are key factors, allowing the formation of reticular nanophases when kinetically in-phase. Moreover, we observe spontaneous structural evolution, resulting in gyrified structures akin to the human brain. The hybridized gyrified reticular nanophases exhibit strain-invariant metallic electrical conductivity up to 156% areal strain, unparalleled durability in organic solvents and aqueous environments with pH 2-13, and high mechanical robustness, a prerequisite for environmentally resilient devices.

3.
ACS Appl Mater Interfaces ; 16(1): 1187-1197, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38126816

RESUMO

The evolving need for all-weather light detection and ranging (LiDAR) sensors and cameras for autonomous vehicles, remote sensing surveillance, and space exploration has spurred the development of transparent heaters. While LiDAR photon sources have shifted from the visible to the near-infrared (NIR) range, the use of transparent conductive oxides (TCOs) for heaters leads to significant optical losses due to their high plasmonic absorption and reflection in the NIR range. Although different TCO compositions can be employed to preserve transparency and electrical conductivity in this range, the choice of dopants, their concentrations, and the underlying mechanisms remain largely unknown. In this study, we present TCOs specifically designed for NIR applications with a focus on identifying new compositions that strike a balance between NIR transparency and electrical conductivity. We present a 4B-6B transition-metal-doped indium oxide thin-film heater that exhibits impressive NIR transmittance (>90%) surpassing that of commonly used indium tin oxide films. By incorporating effective dopants such as titanium, hafnium, and tungsten, we successfully reduced the resistivity and enhanced the electrical conductivity of indium oxide films. To enhance the practical utility of the film, we implemented post-treatments comprising argon plasma treatment and encapsulation with low-molecular-weight poly(dimethylsiloxane), which resulted in significantly improved performance. The optimized film exhibited a sheet resistance of 520 Ω/sq and excellent optical transmittance at 850 nm (89.1%), 905 nm (89.7%), and 1550 nm (92%). Moreover, we successfully integrated defogging and defrosting capabilities into a commercial LiDAR camera and demonstrated its reliable operation in challenging environments.

4.
ACS Nano ; 17(16): 16221-16229, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37540634

RESUMO

Photo(electro)-piezo catalysis has emerged as one of the most effective strategies for sustainable environmental remediation. While various (nano)materials have been investigated for enhancing the intrinsic properties related to the interfacial band structure, increasing the efficiency by integration of materials with rational design for stress-strain applications has not yet been considered. Herein, we introduce kirigami strain engineering to photopiezo catalysts for enhancing efficiency by increasing the magnitude of applied strain and density of bends. Macroscale stretching motion is converted into localized bending by a pliable kirigami structure using similar or even lower input energy, which can be easily modulated by natural waves. The kirigami structure leads to a significant enhancement (∼250%) in the degradation of dyes, and we discovered the significant contribution of the oxygen reduction pathway in the charge-transfer mechanism, which corresponds to the observed enhancement. The photopiezo catalytic effects of kirigami were further highlighted by the small water reservoir test, showing its feasibility in nature for self-sustainable environmental remediation that can be modulated using motions of winds, waves, and life vibrations.

5.
Acc Chem Res ; 56(12): 1359-1372, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37256726

RESUMO

ConspectusChirality is ubiquitous in the universe and in living creatures over detectable length scales from the subatomic to the galactic, as exemplified in the two extremes by subatomic particles (neutrinos) and spiral galaxies. Between them are living creatures that display multiple levels of chirality emerging from hierarchically assembled asymmetric building blocks. Not too far from the bottom of this pyramid are the foundational building blocks with chiral atomic centers on sp3 carbon atoms exemplified by l-amino acids and d-sugars that are self-assembled into higher-order structures with increasing dimensions forming highly complex, amazingly functional, and energy-efficient living systems. The organization and materials employed in their construction inspired scientists to replicate complex living systems via the self-assembly of chiral components. Multiple studies pointed to unexpected and unique electromagnetic properties of chiral structures with nanoscale and microscale dimensions, including giant circular dichroism and collective circularly polarized scattering that their constituent units did not possess.To address the wide variety of chiral geometries observed in continuous materials, singular particles, and their complex systems, multiple analytic techniques are needed. Simultaneously, their spectroscopic properties create a pathway to multiple applications. For example, mirror-asymmetric vibrations at chiral centers formed by sp3 carbon atoms lead to optical activity for the infrared (IR) wavelength regions. At the same time, understanding the optical activity in, for example, the IR region enables biomedical applications because multiple modalities of biomedical imaging and vibrational optical activity (VOA) of biomolecules are known for IR range. In turn, VOA can be realized in both absorption and emission modalities due to large magnetic transition moments, as vibrational circular dichroism (VCD) or Raman optical activity (ROA) spectroscopy. In addition to the VOA, in the range of longer wavelengths, lattice vibrational mode or phononic behavior occurs in chiral crystals and nanoassemblies, which can be readily detected by terahertz circular dichroism (TCD) spectroscopy. Meanwhile, chiral self-assembly can induce circularly polarized light emission (CPLE) regardless of the existence of chirality in coassembled fluorophores. The CPLE from self-assembled chiral materials is particularly interesting because the CPLE can originate from both circularly polarized luminescence and circularly polarized scattering (CPS). Furthermore, because self-assembled nanostructures often exhibit stronger optical activity than their building blocks owing to dimension and resonance effects, the optical activity of single assembled nanostructures can be investigated by using microscopic technology combined with chiral optics. Here, we describe the state of the art for spectroscopic methods for the comprehensive analysis of chiral nanomaterials at various photon wavelengths, addressed with special attention given to new tools emerging both for materials with self-organized hierarchical chirality and single-particle spectroscopy.

6.
Nature ; 615(7952): 418-424, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36922612

RESUMO

Chirality is a geometrical property described by continuous mathematical functions1-5. However, in chemical disciplines, chirality is often treated as a binary left or right characteristic of molecules rather than a continuity of chiral shapes. Although they are theoretically possible, a family of stable chemical structures with similar shapes and progressively tuneable chirality is yet unknown. Here we show that nanostructured microparticles with an anisotropic bowtie shape display chirality continuum and can be made with widely tuneable twist angle, pitch, width, thickness and length. The self-limited assembly of the bowties enables high synthetic reproducibility, size monodispersity and computational predictability of their geometries for different assembly conditions6. The bowtie nanoassemblies show several strong circular dichroism peaks originating from absorptive and scattering phenomena. Unlike classical chiral molecules, these particles show a continuum of chirality measures2 that correlate exponentially with the spectral positions of the circular dichroism peaks. Bowtie particles with variable polarization rotation were used to print photonically active metasurfaces with spectrally tuneable positive or negative polarization signatures for light detection and ranging (LIDAR) devices.

7.
J Am Chem Soc ; 144(50): 22789-22804, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36490376

RESUMO

Chemical, physical, biological and materials engineering disciplines use a variety of chiroptical spectroscopies to probe geometrical and optical asymmetry in molecules and particles. Electronic (ECD) and vibrational (VCD) circular dichroism are the most common of these techniques and collectively enable the studies of electronic and vibronic transitions with energies between 0.1 and 5.0 eV. The vibrational states with characteristic energies in the range of 0.001-0.01 eV carry valuable information about concerted intermolecular motions in molecules and crystals involving multiple atoms. These vibronic transitions located in the terahertz (THz) part of the spectrum become increasingly more important for the chemistry, physics, and biology of complex molecules and materials However, the methodology and hardware of THz circular dichroism (TCD) are much less developed than the chiroptical spectroscopies for ultraviolet, visible, near- and mid infrared photons. Here we provide theoretical foundations, practical implementations, comparative assessments, and exemplary applications of TCD spectroscopy. We show that the sign, intensity, and position of TCD peaks are highly sensitive to the three-dimensional structure and long-range organization of molecular crystals, which offer unique capabilities to study (bio) molecules, their crystals, and nanoscale assemblies and apply the novel data processing methodologies. TCD also offers a convenient toolbox to identify new physical phenomena, such as chiral phonons and their propagation in nanostructured matter. We also discuss the major challenges, emerging opportunities and promising research directions, including broad investigation of chiral phonons observed in chiral (nano) crystals and emerging machine learning methodologies for TCD in biological and nanoscale structures. Ubiquity of low-frequency vibrations with rotational components in biomolecular structures, combined with sharpness of peaks in TCD spectra, enables a variety of technological translations.


Assuntos
Vibração , Dicroísmo Circular , Movimento (Física)
8.
Nano Converg ; 9(1): 32, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35851425

RESUMO

Research on chiral nanomaterials (NMs) has grown radically with a rapid increase in the number of publications over the past decade. It has attracted a large number of scientists in various fields predominantly because of the emergence of unprecedented electric, optical, and magnetic properties when chirality arises in NMs. For applications, it is particularly informative and fascinating to investigate how chiral NMs interact with electromagnetic waves and magnetic fields, depending on their intrinsic composition properties, atomic distortions, and assembled structures. This review provides an overview of recent advances in chiral NMs, such as semiconducting, metallic, and magnetic nanostructures.

9.
Nature ; 601(7893): 366-373, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35046606

RESUMO

Chirality is a unifying structural metric of biological and abiological forms of matter. Over the past decade, considerable clarity has been achieved in understanding the chemistry and physics of chiral inorganic nanoparticles1-4; however, little is known about their effects on complex biochemical networks5,6. Intermolecular interactions of biological molecules and inorganic nanoparticles show some commonalities7-9, but these structures differ in scale, in geometry and in the dynamics of chiral shapes, which can both impede and strengthen their mirror-asymmetric complexes. Here we show that achiral and left- and right-handed gold biomimetic nanoparticles show different in vitro and in vivo immune responses. We use irradiation with circularly polarized light (CPL) to synthesize nanoparticles with controllable nanometre-scale chirality and optical anisotropy factors (g-factors) of up to 0.4. We find that binding of nanoparticles to two proteins from the family of adhesion G-protein-coupled receptors (AGPCRs)-namely cluster-of-differentiation 97 (CD97) and epidermal-growth-factor-like-module receptor 1 (EMR1)-results in the opening of mechanosensitive potassium-efflux channels, the production of immune signalling complexes known as inflammasomes, and the maturation of mouse bone-marrow-derived dendritic cells. Both in vivo and in vitro immune responses depend monotonically on the g-factors of the nanoparticles, indicating that nanoscale chirality can be used to regulate the maturation of immune cells. Finally, left-handed nanoparticles show substantially higher (1,258-fold) efficiency compared with their right-handed counterparts as adjuvants for vaccination against the H9N2 influenza virus, opening a path to the use of nanoscale chirality in immunology.


Assuntos
Proteínas de Ligação ao Cálcio , Células Dendríticas , Inflamassomos , Nanopartículas Metálicas , Receptores Acoplados a Proteínas G , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Células Dendríticas/imunologia , Ouro , Vírus da Influenza A Subtipo H9N2 , Mecanotransdução Celular , Nanopartículas Metálicas/química , Camundongos , Canais de Potássio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Estereoisomerismo
10.
ACS Appl Mater Interfaces ; 14(1): 20-31, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34914354

RESUMO

Tissue microarchitecture imposes physical constraints to the migration of individual cells. Especially in cancer metastasis, three-dimensional structural barriers within the extracellular matrix are known to affect the migratory behavior of cells, regulating the pathological state of the cells. Here, we employed a culture platform with micropillar arrays of 2 µm diameter and 16 µm pitch (2.16 micropillar) as a mechanical stimulant. Using this platform, we investigated how a long-term culture of A549 human lung carcinoma cells on the (2.16) micropillar-embossed dishes would influence the pathological state of the cell. A549 cells grown on the (2.16) micropillar array with 10 µm height exhibited a significantly elongated morphology and enhanced migration even after the detachment and reattachment, as evidenced in the conventional wound-healing assay, single-cell tracking analysis, and in vivo tumor colonization assays. Moreover, the pillar-induced morphological deformation in nuclei was accompanied by cell-cycle arrest in the S phase, leading to suppressed proliferation. While these marked traits of morphology-migration-proliferation support more aggressive characteristics of metastatic cancer cells, typical indices of epithelial-mesenchymal transition were not found, but instead, remarkable traces of amoeboidal transition were confirmed. Our study also emphasizes the importance of mechanical stimuli from the microenvironment during pathogenesis and how gained traits can be passed onto subsequent generations, ultimately affecting their pathophysiological behavior. Furthermore, this study highlights the potential use of pillar-based mechanical stimuli as an in vitro cell culture strategy to induce more aggressive tumorigenic cancer cell models.


Assuntos
Técnicas de Cultura de Células/métodos , Neoplasias Pulmonares/metabolismo , Células A549 , Animais , Técnicas de Cultura de Células/instrumentação , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Ácidos Graxos/metabolismo , Feminino , Humanos , Fenômenos Mecânicos , Metabolômica , Camundongos Endogâmicos BALB C , Camundongos Nus , Pontos de Checagem da Fase S do Ciclo Celular/fisiologia
11.
Adv Mater ; 33(41): e2104769, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34486188

RESUMO

Mechanical-strain-gated switches are cornerstone components of material-embedded circuits that perform logic operations without using conventional electronics. This technology requires a single material system to exhibit three distinct functionalities: strain-invariant conductivity and an increase or decrease of conductivity upon mechanical deformation. Herein, mechanical-strain-gated electric switches based on a thin-film architecture that features an insulator-to-conductor transition when mechanically stretched are demonstrated. The conductivity changes by nine orders of magnitude over a wide range of tunable working strains (as high as 130%). The approach relies on a nanometer-scale sandwiched bilayer Au thin film with an ultrathin poly(dimethylsiloxane) elastomeric barrier layer; applied strain alters the electron tunneling currents through the barrier. Mechanical-force-controlled electric logic circuits are achieved by realizing strain-controlled basic (AND and OR) and universal (NAND and NOR) logic gates in a single system. The proposed material system can be used to fabricate material-embedded logics of arbitrary complexity for a wide range of applications including soft robotics, wearable/implantable electronics, human-machine interfaces, and Internet of Things.

12.
Korean J Radiol ; 22(8): 1253-1265, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33938647

RESUMO

OBJECTIVE: To investigate the prognostic value of preoperative cardiac magnetic resonance imaging (MRI) for long-term major adverse cardiac and cerebrovascular events (MACCEs) in patients undergoing tricuspid valve (TV) surgery for functional tricuspid regurgitation (TR). MATERIALS AND METHODS: The preoperative cardiac MR images, New York Heart Association functional class, comorbidities, and clinical events of 78 patients (median [interquartile range], 59 [51-66.3] years, 28.2% male) who underwent TV surgery for functional TR were comprehensively reviewed. Cox proportional hazards analyses were performed to assess the associations of clinical and imaging parameters with MACCEs and all-cause mortality. RESULTS: For the median follow-up duration of 5.4 years (interquartile range, 1.2-6.6), MACCEs and all-cause mortality were 51.3% and 23.1%, respectively. The right ventricular (RV) end-systolic volume index (ESVI) and the systolic RV mass index (RVMI) were higher in patients with MACCEs than those without them (77 vs. 68 mL/m², p = 0.048; 23.5 vs. 18.0%, p = 0.011, respectively). A high RV ESVI was associated with all-cause mortality (hazard ratio [HR] per value of 10 higher ESVI = 1.10, p = 0.03). A high RVMI was also associated with all-cause mortality (HR per increase of 5 mL/m² RVMI = 1.75, p < 0.001). After adjusting for age and sex, only RVMI remained a significant predictor of MACCEs and all-cause mortality (p < 0.05 for both). After adjusting for multiple clinical variables, RVMI remained significantly associated with all-cause mortality (p = 0.005). CONCLUSION: RVMI measured on preoperative cardiac MRI was an independent predictor of long-term outcomes in patients who underwent TV surgery for functional TR.


Assuntos
Insuficiência da Valva Tricúspide , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Prognóstico , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/cirurgia
13.
Sci Rep ; 10(1): 2764, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066791

RESUMO

The time-of-flight (ToF) principle is a method used to measure distance and construct three-dimensional (3D) images by detecting the time or the phase difference between emitted and back-reflected optical flux. The ToF principle has been employed for various applications including light ranging and detection (LiDAR), machine vision and biomedical engineering; however, bulky system size and slow switching speed have hindered the widespread application of ToF technology. To alleviate these issues, a demonstration of hetero-integration of GaN-based high electron mobility transistors (HEMTs) and GaAs-based vertical cavity surface emitting lasers (VCSELs) on a single platform via a cold-welding method was performed. The hetero-integrated ToF sensors show superior switching performance when compared to silicon-transistor-based systems, miniaturizing size and exhibiting stable ranging and high-resolution depth-imaging. This hetero-integrated system of dissimilar material-based high-performance devices suggests a new pathway towards enabling high-resolution 3D imaging and inspires broader range application of heterogeneously integrated electronics and optoelectronics.

14.
Nanoscale ; 11(32): 15374-15381, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31389946

RESUMO

Semiconductor gas sensors are advantageous in miniaturization and can be used in a wide range of applications, yet consume large power due to high operating temperature. Here we demonstrated the ability of nanoscale scratches produced with mechanical abrasion to enhance the chemical sensitivity of thin-film-type semiconductor sensors. Well-aligned arrays of scratches parallel to the electrical current direction between the source and drain electrodes were made, using typical polishing machines with diamond suspensions, on semiconductor thin films produced with various deposition methods such as atomic layer deposition (ALD), sputtering, and the sol-gel technique. Processing with sharp diamond microparticles left nano-grooves on the surface, together with changes in chemical composition. For all of the tested metal oxide thin films, the introduction of scratches yielded increased quantities of oxygen vacancies and metallic components. Scratched ZnO devices exhibited superior performance even at room temperature, as predicted by a computational simulation that showed increased binding energy of gas molecules on defects. The scratch technique shown in the present study may be used to produce dense arrays of nanometer-scale, chemically functionalized line patterns on substrates larger than a few tens of centimeters with minimum cost, which in turn may be used in a variety of applications including massive arrays of sensors displaying high sensitivity.

15.
Nat Mater ; 18(8): 820-826, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31263226

RESUMO

Terahertz circular dichroism (TCD) offers multifaceted spectroscopic capabilities for understanding the mesoscale chiral architecture and low-energy vibrations of macromolecules in (bio)materials1-5. However, the lack of dynamic polarization modulators comparable to polarization optics for other parts of the electromagnetic spectrum is impeding the proliferation of TCD spectroscopy6-11. Here we show that tunable optical elements fabricated from patterned plasmonic sheets with periodic kirigami cuts make possible the polarization modulation of terahertz radiation under application of mechanical strain. A herringbone pattern of microscale metal stripes enables a dynamic range of polarization rotation modulation exceeding 80° over thousands of cycles. Following out-of-plane buckling, the plasmonic stripes function as reconfigurable semi-helices of variable pitch aligned along the terahertz propagation direction. Several biomaterials, exemplified by an elytron of the Chrysina gloriosa, revealed distinct TCD fingerprints associated with the helical substructure in the biocomposite. Analogous kirigami modulators will also enable other applications in terahertz optics, such as polarization-based terahertz imaging, line-of-sight telecommunication, information encryption and space exploration.


Assuntos
Materiais Biocompatíveis/química , Dicroísmo Circular/métodos , Radiação Terahertz
16.
Sci Rep ; 9(1): 1834, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755647

RESUMO

Precise modulation of polymer brush in its thickness and grafting density can cause unexpected cell behaviors and regulated bioactivities. Herein, a nanoscale poly(dimethylsiloxane) (PDMS) brush was employed to use as a controllable material for cell adhesion. Facile fabrication of ultrathin monolayer PDMS nanobrush on an underlying substrate facilitated regaining cell adhesion through long-range cell attractive forces such as the van der Waals forces. We showed that cell adhesion is diminished by increasing the number of nanobrush layers, causing a gradual decrease of the effectiveness of the long-range force. The result demonstrates that ultrathin PDMS nanobrush can either promote or inhibit cell adhesion, which is required for various biomedical fields such as tissue-engineering, anti-fouling coating, and implantable biomaterials and sensors.


Assuntos
Dimetilpolisiloxanos/química , Nanoestruturas/química , Engenharia Tecidual/instrumentação , Animais , Materiais Biocompatíveis , Técnicas Biossensoriais , Adesão Celular , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Camundongos , Microscopia Confocal , Microscopia de Fluorescência , Células NIH 3T3 , Oxigênio/química , Polímeros/química , Propriedades de Superfície , Engenharia Tecidual/métodos
17.
Korean J Radiol ; 19(5): 888-896, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30174478

RESUMO

Objective: To evaluate the differences in subjective calcification detection rates and objective calcium volumes in lung nodules according to different reconstruction methods using hybrid kernel (FC13-H) and iterative reconstruction (IR). Materials and Methods: Overall, 35 patients with small (< 4 mm) calcified pulmonary nodules on chest CT were included. Raw data were reconstructed using filtered back projection (FBP) or IR algorithm (AIDR-3D; Canon Medical Systems Corporation), with three types of reconstruction kernel: conventional lung kernel (FC55), FC13-H and conventional soft tissue kernel (FC13). The calcium volumes of pulmonary nodules were quantified using the modified Agatston scoring method. Two radiologists independently interpreted the role of each nodule calcification on the six types of reconstructed images (FC55/FBP, FC55/AIDR-3D, FC13-H/FBP, FC13-H/AIDR-3D, FC13/FBP, and FC13/AIDR-3D). Results: Seventy-eight calcified nodules detected on FC55/FBP images were regarded as reference standards. The calcium detection rates of FC55/AIDR-3D, FC13-H/FBP, FC13-H/AIDR-3D, FC13/FBP, and FC13/AIDR-3D protocols were 80.7%, 15.4%, 6.4%, 52.6%, and 28.2%, respectively, and FC13-H/AIDR-3D showed the smallest calcium detection rate. The calcium volume varied significantly with reconstruction protocols and FC13/AIDR-3D showed the smallest calcium volume (0.04 ± 0.22 mm3), followed by FC13-H/AIDR-3D. Conclusion: Hybrid kernel and IR influence subjective detection and objective measurement of calcium in lung nodules, particularly when both techniques (FC13-H/AIDR-3D) are combined.


Assuntos
Calcinose/diagnóstico , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Algoritmos , Área Sob a Curva , Artefatos , Cálcio/análise , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Curva ROC , Doses de Radiação , Análise Espacial , Tórax/diagnóstico por imagem
18.
Biochem Pharmacol ; 149: 124-130, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29132976

RESUMO

Carbonyl sulfide (COS) releasing scaffolds are gaining popularity as hydrogen sulfide (H2S) donors through exploitation of the carbonic anhydrase (CA)-mediated hydrolysis of COS to H2S. The majority of compounds in this emerging class of donors undergo triggerable decomposition (often referred to as self-immolation) to release COS, and a handful of different COS-releasing structures have been reported. One benefit of this donation strategy is that numerous caged COS-containing core motifs are possible and are poised for development into self-immolative COS/H2S donors. Because the intermediate release of COS en route to H2S donation requires CA, it is important that the COS donor motifs do not inhibit CA directly. In this work, we investigate the cytotoxicity and CA inhibition properties of different caged COS donor cores, as well as caged CO2 and CS2 motifs and non-self-immolative control compounds. None of the compounds investigated exhibited significant cytotoxicity or enhanced cell proliferation at concentrations up to 100 µM in A549 cells, but we identified four core structures that function as CA inhibitors, thus providing a roadmap for the future development of self-immolative COS/H2S donor motifs.


Assuntos
Inibidores da Anidrase Carbônica/farmacologia , Óxidos de Enxofre/farmacologia , Células A549 , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Inibidores da Anidrase Carbônica/química , Anidrases Carbônicas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Estrutura Molecular , Óxidos de Enxofre/química
19.
Korean J Radiol ; 18(4): 664-673, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28670161

RESUMO

OBJECTIVE: To assess the normal reference values of left ventricle (LV) functional parameters in Korean adults on coronary CT angiography (CCTA) with a 320-detector-row CT scanner, and to analyze sex-related differences and correlations with various clinical characteristics. MATERIALS AND METHODS: This study retrospectively enrolled 172 subjects (107 men and 65 women; age, 58 ± 10.9 years; body surface area [BSA], 1.75 ± 0.2 m2) who underwent CCTA without any prior history of cardiac disease. The following parameters were measured by post-processing the CT data: LV volume, LV functional parameters (ejection fraction, stroke volume, cardiac output, etc.), LV myocardial mass, LV inner diameter, and LV myocardial thickness (including septal wall thickness [SWT], posterior wall thickness [PWT], and relative wall thickness [RWT = 2 × PWT / LV inner diameter]). All of the functional or volumetric parameters were normalized using the BSA. The general characteristics and co-morbidities for the enrolled subjects were recorded, and the correlations between these factors and the LV parameters were then evaluated. RESULTS: The LV myocardial thickness (SWT, 1.08 ± 0.18 cm vs. 0.90 ± 0.17 cm, p < 0.001; PWT, 0.91 ± 0.15 cm vs. 0.78 ± 0.10 cm, p < 0.001; RWT, 0.38 ± 0.08 cm vs. 0.33 ± 0.05 cm, p < 0.001), LV volume (LV end-diastolic volume, 112.9 ± 26.1 mL vs. 98.2 ± 21.0 mL, p < 0.001; LV end-systolic volume, 41.7 ± 14.7 mL vs. 33.7 ± 12.2 mL, p = 0.001) and mass (145.0 ± 29.1 g vs. 107.9 ± 20.0 g, p < 0.001) were significantly greater in men than in women. However, these differences were not significant after normalization using BSA, except for the LV mass (LV mass index, 79.6 ± 14.0 g/m2 vs. 66.2 ± 11.0 g/m2, p < 0.001). The cardiac output and ejection fraction were not significantly different between the men and women (cardiac output, 4.3 ± 1.0 L/min vs. 4.2 ± 0.9 L/min, p = 0.452; ejection fraction, 63.4 ± 7.7% vs. 66.4 ± 7.6%, p = 0.079). Most of the LV parameters were positively correlated with BSA, body weight, and total Agatston score. CONCLUSION: This study provides sex-related reference values and percentiles for LV on cardiac CT and should assist in interpreting results.


Assuntos
Angiografia por Tomografia Computadorizada , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Povo Asiático , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Estudos Retrospectivos , Volume Sistólico
20.
Med Mycol ; 55(4): 349-357, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28339533

RESUMO

It is difficult to differentiate Pneumocystis pneumonia (PCP) from rituximab-induced interstitial lung disease (RILD) in lymphoma patients with diffuse pulmonary infiltrates who are receiving rituximab-containing chemotherapy. Using a clinical scoring system, we aim to differentiate PCP from RILD who are receiving rituximab-containing chemotherapy. We reviewed the medical records of lymphoma patients who had received rituximab-containing chemotherapy between 2012 and 2015 in a tertiary hospital. Among 613 lymphoma patients receiving rituximab-containing chemotherapy, 97 (16%) had diffuse pulmonary infiltrates. Of these, 16 (16%) with an alternative diagnosis and 22 (23%) with an indeterminate diagnosis were excluded. Finally, 21 (22%) patients were classified as having PCP and the remaining 38 (39%) as having RILD. Fever, short duration of symptoms (≤5 days), systemic inflammatory response syndrome (SIRS), and severe extent of disease on CT scan (>75%) were more common in patients with PCP than in those with RILD. Clinical scores were determined using the following system: SIRS = score 1, symptom duration ≤5 days = score 1, extent of disease on CT >75% = score 4. A score of ≥2 differentiated PCP from RILD with 91% sensitivity (95% CI, 70-99) and 71% specificity (95% CI, 54-84). A clinical scoring system based on presence of SIRS, short duration of symptoms, and severe extent of disease on CT scan appears to be useful in differentiation of PCP from RILD.


Assuntos
Antineoplásicos Imunológicos/efeitos adversos , Doenças Pulmonares Intersticiais/induzido quimicamente , Doenças Pulmonares Intersticiais/diagnóstico , Linfoma/complicações , Linfoma/tratamento farmacológico , Pneumonia por Pneumocystis/diagnóstico , Rituximab/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Técnicas de Apoio para a Decisão , Diagnóstico Diferencial , Tratamento Farmacológico/métodos , Feminino , Humanos , Doenças Pulmonares Intersticiais/patologia , Masculino , Pessoa de Meia-Idade , Pneumonia por Pneumocystis/patologia , Estudos Retrospectivos , Rituximab/uso terapêutico , Centros de Atenção Terciária , Adulto Jovem
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