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1.
Hepatol Res ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459823

RESUMO

A 70-year-old man undergoing treatment for immunoglobulin G4-related disease developed a liver mass on computed tomography during routine imaging examination. The tumor was located in the hepatic S1/4 region, was 38 mm in size, and showed arterial enhancement on dynamic contrast-enhanced computed tomography. We performed a liver biopsy and diagnosed moderately differentiated hepatocellular carcinoma. The patient underwent proton beam therapy. The tumor remained unchanged but enlarged after 4 years. The patient was diagnosed with hepatocellular carcinoma recurrence and received hepatic arterial chemoembolization. However, 1 year later, the patient developed jaundice, and the liver tumor grew in size. Unfortunately, the patient passed away. Autopsy revealed that the tumor consisted of spindle-shaped cells exhibiting nuclear atypia and a fission pattern and tested positive for α-smooth muscle actin and vimentin. No hepatocellular carcinoma components were observed, and the patient was pathologically diagnosed with hepatic leiomyosarcoma. Next-generation sequencing revealed somatic mutations in CACNA2D4, CTNNB1, DOCK5, IPO8, MTMR1, PABPC5, SEMA6D, and ZFP36L1. Based on the genetic mutation, sarcomatoid hepatocarcinoma was the most likely pathogenesis in this case. This mutation is indicative of the transition from sarcomatoid hepatocarcinoma to hepatic leiomyosarcoma.

2.
Acta Radiol ; : 2841851241253775, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785068

RESUMO

BACKGROUND: Brain magnetic resonance imaging voxel-based morphometry (VBM) and perfusion single-photon emission computed tomography (SPECT) are useful for differentiating dementia with Lewy bodies (DLB) from Alzheimer's disease (AD). PURPOSE: To determine whether combining multiple parameters of VBM and SPECT using a multiparametric scoring system (MSS) improves diagnostic accuracy in differentiating DLB from AD. MATERIAL AND METHODS: In total, 23 patients with DLB and 57 patients with AD underwent imaging using a voxel-based specific regional analysis system for AD (VSRAD), an easy Z-score imaging system, and a Z-Graph using three-dimensional stereotactic surface projection. The cutoff values were determined using the receiver operating characteristic curve to differentiate DLB from AD for all parameters. Patients were scored 1 (DLB) or 0 (AD) for each statistically significant parameter, according to a threshold. The total score was determined for each case to obtain a cutoff value for the MSS. RESULTS: The mean Z-scores in the medial temporal lobes using the VSRAD were significantly lower in patients with DLB than in those with AD. Each Z-score of the summed Z-scores in all four segmented regions of the occipital lobes using the Z-Graph was significantly higher in patients with DLB than in those with AD. Among the five parameters, the highest accuracy was 80% for the Z-score of the summed Z-scores in the left medial occipital lobe. For the MSS, a cutoff value of four improved the diagnostic accuracy to 82%. CONCLUSION: MSS was more accurate than any single parameter of VBM or SPECT in differentiating DLB from AD.

3.
J Am Chem Soc ; 145(13): 7528-7539, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36947735

RESUMO

Hole-collecting monolayers have drawn attention in perovskite solar cell research due to their ease of processing, high performance, and good durability. Since molecules in the hole-collecting monolayer are typically composed of functionalized π-conjugated structures, hole extraction is expected to be more efficient when the π-cores are oriented face-on with respect to the adjacent surfaces. However, strategies for reliably controlling the molecular orientation in monolayers remain elusive. In this work, multiple phosphonic acid anchoring groups were used to control the molecular orientation of a series of triazatruxene derivatives chemisorbed on a transparent conducting oxide electrode surface. Using infrared reflection absorption spectroscopy and metastable atom electron spectroscopy, we found that multipodal derivatives align face-on to the electrode surface, while the monopodal counterpart adopts a more tilted configuration. The face-on orientation was found to facilitate hole extraction, leading to inverted perovskite solar cells with enhanced stability and high-power conversion efficiencies up to 23.0%.

4.
Opt Express ; 31(8): 12739-12755, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157429

RESUMO

A Fresnel Zone Aperture (FZA) mask for a lensless camera, an ultra-thin and functional computational imaging system, is beneficial because the FZA pattern makes it easy to model the imaging process and reconstruct captured images through a simple and fast deconvolution. However, diffraction causes a mismatch between the forward model used in the reconstruction and the actual imaging process, which affects the recovered image's resolution. This work theoretically analyzes the wave-optics imaging model of an FZA lensless camera and focuses on the zero points caused by diffraction in the frequency response. We propose a novel idea of image synthesis to compensate for the zero points through two different realizations based on the linear least-mean-square-error (LMSE) estimation. Results from computer simulation and optical experiments verify a nearly two-fold improvement in spatial resolution from the proposed methods compared with the conventional geometrical-optics-based method.

5.
Chemistry ; 29(34): e202300529, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37005224

RESUMO

Organic dyes with strong absorption in the near-infrared (NIR) region are potentially useful in medical applications, such as tumor imaging and photothermal therapy. In this work, new NIR dyes combining BAr2 -bridged azafulvene dimer acceptors with diarylaminothienyl donors in a donor-acceptor-donor configuration were synthesized. Surprisingly, it was found that in these molecules the BAr2 -bridged azafulvene acceptor adopts a 5-membered, rather than 6-membered ring structure. The influence of the aryl substituents on the HOMO and LUMO energy levels of the dye compounds was assessed from electrochemical and optical measurements. Strong electron-withdrawing fluorinated substituents (Ar=C6 F5 , 3,5-(CF3 )2 C6 H3 ) lowered the HOMO energy while preserving the small HOMO-LUMO energy gap, resulting in promising NIR dye molecules that combine strong absorption bands centered around 900 nm with good photostability.

6.
Conscious Cogn ; 116: 103604, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37976782

RESUMO

Through the neurally evolving process of dynamic contextual modulation of perceptual contents, it remains unclear how the content of awareness is determined. Here we quantified the visual illusion of orientation repulsion, wherein the target appears tilted against the surrounding's orientation, and examined whether its extent changed when the target awareness was quickened by a preceding flanker. Independently of spatial cueing, repulsion was reduced when the flanker preceded the target by 100 ms compared with when they appeared simultaneously. We confirmed that the preceding flanker quickened the awareness of a nearby target relative to distant ones by 40 ms. Furthermore, the preceding flanker that was greater than 7 degrees away from the target still evoked such reduction of repulsion. These findings imply that the content of awareness is determined by the temporal interaction of two distinct processes: one controls the moment of awareness, and the other represents the perceptual content.


Assuntos
Ilusões , Humanos , Ilusões/fisiologia , Sinais (Psicologia)
7.
BMC Neurosci ; 23(1): 57, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180823

RESUMO

BACKGROUND: Auditory steady-state responses (ASSRs) are periodic evoked responses to constant periodic auditory stimuli, such as click trains, and are suggested to be associated with higher cognitive functions in humans. Since ASSRs are disturbed in human psychiatric disorders, recording ASSRs from awake intact macaques would be beneficial to translational research as well as an understanding of human brain function and its pathology. However, ASSR has not been reported in awake macaques. RESULTS: Electroencephalograms (EEGs) were recorded from awake intact macaques, while click trains at 20-83.3 Hz were binaurally presented. EEGs were quantified based on event-related spectral perturbation (ERSP) and inter-trial coherence (ITC), and ASSRs were significantly demonstrated in terms of ERSP and ITC in awake intact macaques. A comparison of ASSRs among different click train frequencies indicated that ASSRs were maximal at 83.3 Hz. Furthermore, analyses of laterality indices of ASSRs showed that no laterality dominance of ASSRs was observed. CONCLUSIONS: The present results demonstrated ASSRs, comparable to those in humans, in awake intact macaques. However, there were some differences in ASSRs between macaques and humans: macaques showed maximal ASSR responses to click frequencies higher than 40 Hz that has been reported to elicit maximal responses in humans, and showed no dominant laterality of ASSRs under the electrode montage in this study compared with humans with right hemisphere dominance. The future ASSR studies using awake intact macaques should be aware of these differences, and possible factors, to which these differences were ascribed, are discussed.


Assuntos
Potenciais Evocados Auditivos , Vigília , Estimulação Acústica/métodos , Animais , Eletroencefalografia/métodos , Potenciais Evocados Auditivos/fisiologia , Macaca
8.
Opt Express ; 30(14): 25006-25019, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237041

RESUMO

This study proposes a novel computational imaging system that integrates a see-through screen (STS) with volume holographic optical elements (vHOEs) and a digital camera unit. Because of the unique features of the vHOE, the STS can function as a holographic waveguide device (HWD) and enable the camera to capture the frontal image when the user gazes at the screen. This system not only provides an innovative solution to a high-quality video communication system by realizing eye-contact but also contributes to other visual applications due to its refined structure. However, there is a dilemma in the proposed imaging system: for a wider field of view, a larger vHOE is necessary. If the size of the vHOE is larger, the light rays from the same object point are diffracted at different Bragg conditions and reflect a different number of times, which causes blurring of the captured image. The system imaging process is analyzed by ray tracing, and a digital image reconstruction method was employed to obtain a clear picture in this study. Optical experiments confirmed the effectiveness of the proposed HWD-STS camera.

9.
Int J Med Sci ; 19(8): 1320-1333, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928727

RESUMO

Background/Aim: Cancer research has been conducted using cultured cells as part of drug discovery testing, but conventional two-dimensional culture methods are unable to reflect the complex tumor microenvironment. On the other hand, three-dimensional cultures have recently been attracting attention as in vitro models that more closely resemble the in vivo physiological environment. The purpose of this study was to establish a 3D culture method for oral cancer and to verify its practicality. Materials and Methods: Three-dimensional cultures were performed using several oral cancer cell lines. Western blotting was used for protein expression analysis of the collected cell masses (spheroids), and H-E staining was used for structural observation. The cultures were exposed to cisplatin and cetuximab and the morphological changes of spheroids over time and the expression changes of target proteins were compared. Results: Each cell line formed spheroidal cell aggregates and showed enhancement of cell adhesion molecules over time. H-E staining showed tumor tissue-like structures specific to each cell line. Cisplatin showed concentration-dependent antitumor effects due to loss of cell adhesion and spheroid disruption in each cell line, while cetuximab exhibited antitumor effects that correlated with EGFR expression in each cell line. Conclusion: Spheroids made from oral cancer cell lines appeared to have tumor-like characteristics that may reflect their clinical significance. In the future, it may become possible to produce tumor spheroids from tissue samples of oral cancer patients, and then apply them to drug screening and to develop individualized diagnostic and treatment methods.


Assuntos
Neoplasias Bucais , Esferoides Celulares , Linhagem Celular Tumoral , Cetuximab/farmacologia , Cetuximab/uso terapêutico , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Humanos , Neoplasias Bucais/tratamento farmacológico , Reprodução , Microambiente Tumoral
10.
Opt Express ; 29(7): 9758-9771, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33820129

RESUMO

We propose a preliminary lensless inference camera (LLI camera) specialized for object recognition. The LLI camera performs computationally efficient data preprocessing on the optically encoded pattern through the mask, rather than performing computationally expensive image reconstruction before inference. Therefore, the LLI camera avoids expensive computation and achieves real-time inference. This work proposes a new data preprocessing approach, named local binary patterns map generation, dedicated for optically encoded pattern through the mask. This preprocessing approach greatly improves encoded pattern's robustness to local disturbances in the scene, making the LLI camera's practical application possible. The performance of the LLI camera is analyzed through optical experiments on handwritten digit recognition and gender estimation under conditions with changing illumination and a moving target.

11.
Opt Express ; 29(23): 37962-37978, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808858

RESUMO

A mask-based lensless camera adopts a thin mask to optically encode the scene and records the encoded pattern on an image sensor. The lensless camera can be thinner, lighter and cheaper than the lensed camera. But additional computation is required to reconstruct an image from the encoded pattern. Considering that the significant application of the lensless camera could be inference, we propose to perform object recognition directly on the encoded pattern. Avoiding image reconstruction not only saves computational resources but also averts errors and artifacts in reconstruction. We theoretically analyze multiplexing property in mask-based lensless optics which maps local information in the scene to overlapping global information in the encoded pattern. To better extract global features, we propose a simplified Transformer-based architecture. This is the first time to study Transformer-based architecture for encoded pattern recognition in mask-based lensless optics. In the optical experiment, the proposed system achieves 91.47% accuracy on the Fashion MNIST and 96.64% ROC AUC on the cats-vs-dogs dataset. The feasibility of physical object recognition is also evaluated.

12.
Phys Rev Lett ; 126(7): 077401, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666485

RESUMO

We investigate the impact of phonon excitations on the photoexcited carrier dynamics in a lead-halide perovskite CH_{3}NH_{3}PbI_{3}, which hosts unique low-energy phonons that can be directly excited by terahertz pulses. Our time-resolved photoluminescence measurements reveal that strong terahertz excitation prolongs the cooling time of hot carriers, providing direct evidence for the hot-phonon bottleneck effect. In contrast to the previous studies where phonons are treated as a passive heat bath, our results demonstrate that phonon excitation can significantly perturb the carrier relaxation dynamics in halide perovskites through the coupling between transverse- and longitudinal-optical phonons.

13.
J Psychiatry Neurosci ; 46(4): E480-E489, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34346201

RESUMO

Background: Abnormally high activity in the lateral habenula causes anxiety- or depression-like behaviours in animal experimental models. It has also been reported in humans that excessive stress in early life is correlated with the onset of psychiatric disorders in adults. These findings raise the question of whether maturation of the lateral habenula is affected under the influence of early-life experiences, which could govern behaviours throughout life. Methods: We examined the maturation of the lateral habenula in mice based on neuronal activity markers and plastic components: Zif268/Egr1, parvalbumin and perineuronal nets. We examined the effect of early-life stress using repeated maternal deprivation. Results: First, we found a transient highly sensitive period of the lateral habenula under stress. The lateral habenula matured through 4 stages: postnatal days 1-9 (P1-9), P10-20, around P35 and after P35. At P10-20, the lateral habenula was highly sensitive to stress. We also observed experience-dependent maturation of the lateral habenula. Only mice exposed to chronic stress from P10-20 exhibited changes specific to the lateral habenula at P60: abnormally high stress reactivity shown by Zif268/Egr1 and fewer parvalbumin neurons. These mice showed anxiety- or depression-like behaviours in the light-dark box test and forced swim test. Limitations: The effect of parvalbumin neurons in the lateral habenula on behavioural alterations remains unknown. It will be important to understand the "sensitive period" of the neuronal circuits in the lateral habenula and how the period P10-20 is different from P9 or earlier, or P35 or later. Conclusion: In mice, early-life stress in the period P10-20 led to late effects in adulthood: hyperactivity in the lateral habenula and anxiety or depression, indicating differences in neuronal plasticity between stages of lateral habenula maturation.


Assuntos
Ansiedade , Depressão , Modelos Animais de Doenças , Habenula , Estresse Psicológico , Animais , Camundongos , Ansiedade/etiologia , Ansiedade/patologia , Biomarcadores , Depressão/etiologia , Depressão/patologia , Habenula/crescimento & desenvolvimento , Habenula/metabolismo , Habenula/patologia , Camundongos Endogâmicos C57BL , Neurônios/metabolismo
14.
Xenobiotica ; 51(7): 771-777, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33947307

RESUMO

We developed an assay system to evaluate the cytochrome P450 (CYP) 3A4-inhibitory activity of compounds, taking account of their cellular permeability, using intestine-derived cell lines pre-treated with the CYP3A4 inducer 1α,25-dihydroxy-vitamin D3 (250 nM).Ketoconazole (KTZ), saquinavir (SQV), naringin, naringenin (NGE), bergamottin (BG), 6',7'-dihydroxybergamottin (DHBG), epigallocatechin gallate (EGCG), and resveratrol (RES) were evaluated as known CYP3A4 inhibitors. The apparent IC50 (IC50,app) values of known inhibitors were determined in Caco-2 cells with 10 µM midazolam as a CYP3A4 substrate, and compared with the IC50 values in a human liver microsome assay.SQV and BG with high lipophilicity and good membrane permeability show similar concentrations inside and outside the cells, and consequently IC50,app and IC50 are similar.KTZ, EGCG, DHBG, NGE, and RES showed a difference between IC50 and IC50,app. This is considered to result from a difference between the intracellular and extracellular concentrations of the compound, which is likely due to the involvement of efflux and/or influx transporters.This method to evaluate CYP inhibition taking account of membrane permeation should be helpful to assess the potential clinical relevance of drug-drug or drug-food interactions in the gastrointestinal tract.


Assuntos
Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450 , Células CACO-2 , Humanos , Intestinos , Microssomos Hepáticos , Vitamina D
15.
J Vis ; 21(8): 5, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34342645

RESUMO

Our conscious awareness of visual events does not arise instantaneously. Previous studies on backward masking have investigated dynamic internal processes making targets visible or invisible subjectively. However, to understand the whole picture of our rich conscious experiences, the emergence of various phenomenal attributes of consciousness beyond visibility must be delineated. We quantified appearance as the strength of orientation repulsion during common-onset masking and found that masking reduced the repulsion in a near-vertical target grating surrounded by tilted inducers. Furthermore, this reduction was seen only when the inducers were presented together with or after the target. This demonstrates that orientation repulsion involves slow contextual modulation and that masking influences this modulation at a later period. Although appearance was altered as such, orientation discriminability was not reduced by masking in any of our experiments. We propose a process in which internal representations of objects spend a certain amount of time evolving before we become aware of them. Backward masking compulsorily terminates this temporal evolution of internal representations and allows premature representations to arise in our awareness.


Assuntos
Estado de Consciência , Mascaramento Perceptivo , Humanos , Estimulação Luminosa , Percepção Visual
16.
Nihon Shokakibyo Gakkai Zasshi ; 118(6): 578-585, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34108358

RESUMO

A 60-year-old man was admitted for investigation of a mediastinal cystic lesion. During endoscopic retrograde pancreatography, the contrast medium leaked from the head of the main pancreatic duct, and the cystic fluid collected with endoscopic ultrasonography (EUS) -guided aspiration showed high levels of pancreatic enzymes. Therefore, we diagnosed mediastinal pancreatic pseudocyst. The pseudocyst shrank as a result of EUS-guided drainage, and an endoscopic nasopancreatic drainage tube was then placed to close the fistula of the pancreatic duct. This case suggests that endoscopic procedures could be useful for the diagnosis and treatment of mediastinal pancreatic pseudocyst. We review 48 case reports of mediastinal pancreatic pseudocyst and discuss the usefulness of endoscopic procedures for diagnosis and treatment.


Assuntos
Pseudocisto Pancreático , Drenagem , Endoscopia , Endossonografia , Humanos , Masculino , Pessoa de Meia-Idade , Ductos Pancreáticos , Pseudocisto Pancreático/diagnóstico por imagem , Pseudocisto Pancreático/cirurgia
17.
Biochem Biophys Res Commun ; 531(3): 422-430, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32800556

RESUMO

Bone destruction of maxillary and mandibular bone by invasive oral squamous cell cancer (OSCC) raises various problems in the management of patients, resulting in poor outcomes and survival. However, the mechanism behind bone destruction by OSCC remains unclear. High-mobility group box 1 (HMGB1), a highly conserved ubiquitous nuclear non-histone DNA-binding protein, has been demonstrated to be secreted by aggressive cancers and regulate osteoclastogenesis, a central player during bone destruction. We therefore reasoned that HMGB1 secreted by OSCCs contributes to bone destruction. Our results showed that HMGB1 is produced by human cell lines of OSCC and promotes osteoclastogenesis via up-regulation of the expression of receptor activator of nuclear factor kappa-Β ligand in osteoblasts and osteocytes, and consequently osteoclastic bone destruction in mice. Further, we found that these actions of HMGB1 are mediated via the receptor for advanced glycation end products and toll-like receptors. These findings suggest that HMGB1 of OSCC and its down-stream signal pathways are potential targets for the treatment of bone destruction associated with advanced OSCC.


Assuntos
Osso e Ossos/patologia , Proteína HMGB1/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Benzamidas/farmacologia , Reabsorção Óssea/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Antígeno Ki-67/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteócitos/efeitos dos fármacos , Osteócitos/metabolismo , Osteogênese/efeitos dos fármacos , Ligante RANK/metabolismo , Células RAW 264.7 , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Sulfonamidas/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores
18.
Opt Express ; 28(26): 39998-40012, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33379536

RESUMO

An imaging system employing a volume holographic optical element (vHOE) has a unique feature by which the image of an object placed in front of a transparent screen can be captured. The system obtains an image of the light diffracted by the vHOE; however, unwanted background components, including direct reflection or transmitted components, are present in the captured image. In this study, we propose a method to eliminate such background components from the captured images via multispectral image processing. The image components obtained from the diffraction by vHOE can be successfully extracted utilizing the facts that it diffracts light with a narrow spectral range and the reflection spectrum of a natural object is mostly smooth in the wavelength axis. Computer simulations and experiments confirm the effectiveness of the proposed method, along with video applications that demonstrate its real-time capability.

19.
Opt Express ; 28(24): 36740-36755, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379761

RESUMO

We propose an interactive optical 3D-touch user interface (UI) by using a holographic light-field (LF) 3D display and a color detection system of the scattered light from the touched 3D image. In the proposed system, color information embedded in the LF is used to realize the 3D position identification and movement detection of the interaction point in 3D space only with a single RGB camera. We demonstrate the real-time interactive implementation of the interface working at 12 frames per second, which verifies the feasibility of our proposed concept.

20.
Opt Express ; 28(26): 39137-39155, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33379470

RESUMO

The Fresnel-zone-aperture lensless camera using a fringe-scanning technique allows non-iterative well-conditioned image reconstruction; however, the spatial resolution is limited by the mathematical reconstruction model that ignores diffraction. To solve this resolution problem, we propose a novel image-reconstruction algorithm using the wave-optics-based design of the deconvolution filter and color-channel image synthesis. We verify a two-fold improvement of the effective angular resolution by conducting numerical simulations and optical experiments with a prototype.

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