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1.
JID Innov ; 2(4): 100121, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35812723

RESUMO

Hair graying in mice is caused by various injuries such as X-ray radiation and repeated plucking that ultimately damage melanocytes and their stem cells (melanocyte stem cells). In X-ray‒induced hair graying, injuries first manifest as a loss-of-niche function of hair follicular keratinocyte stem cells to maintain melanocyte stem cells. Thus, we hypothesized that hair follicular keratinocyte stem cells could be a practical target to prevent hair graying. In this study, we investigated the in vivo effect of the flavonoid hydroxygenkwanin, which has been shown to exert the best protection on human epidermal keratinocytes against in vitro X-ray‒induced cytological effects, using X-ray‒induced and repeated hair plucking‒induced hair graying mice models. We found that hydroxygenkwanin exerted a remarkable effect in preventing hair graying; however, when receptor Y kinase Kit-mutant mice were used, no prevention effect was observed. Therefore, we propose that Kit signaling might be involved in the hydroxygenkwanin-induced protective effect against hair graying.

3.
Sensors (Basel) ; 19(4)2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30769839

RESUMO

In this study, we propose a strategy for delicately grasping fragile objects using a robotic gripper with highly deformable fluid fingertips. In an earlier study, we developed a soft fingertip, referred to as a fluid fingertip, which was fabricated from a deformable rubber bag filled with incompressible fluid. The proposed strategy detects the preferable grasping point where fracturing of the target object is avoided while the applied force or pressure from the fluid fingertip is substantially transmitted to the target. In this grasping point, the behavior of the fluid pressure changes with respect to the pushing distance when pushing at a constant speed. The other features of the strategy determining the grasping point are as follows: (1) the threshold for the detection of the grasping point is fixed or constant with respect to the type of target object; (2) information regarding the deformation and stiffness of the fingertips and target object is not required. The detection of the grasping point through behavioral changes in the pressure is performed by comparing the fitting accuracies of fitting models utilizing information of the fluid pressure and pushing distance. The validity of the proposed approach is verified through several experiments.


Assuntos
Força da Mão/fisiologia , Mãos/fisiologia , Robótica/métodos , Dedos/fisiologia , Humanos , Pressão
4.
Bioorg Med Chem ; 16(24): 10311-8, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18977146

RESUMO

The interaction energy was calculated, by the ab initio FMO method, for complexes between LCK protein and four inhibitors (staurosporine, BMS compound 2, and our compounds 3 and 4). In every case a number of CH/pi hydrogen bonds have been disclosed in the so-called adenine pocket. In complexes of 2, 3, and 4, CH/pi and NH/pi hydrogen bonds have been observed in another pocket. In view of the above results, the aniline ring of 3 was replaced by 2,6-dimethyl aniline to increase the potency for LCK kinase. A 10-fold increase in the potency has been achieved for 4 over 3. We suggest that the concept of weak hydrogen bonds is useful in the rational design of drugs.


Assuntos
Desenho de Fármacos , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/química , Inibidores de Proteínas Quinases/química , Elétrons , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Conformação Proteica , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Termodinâmica
5.
Bioorg Med Chem ; 16(2): 909-21, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17997320

RESUMO

To improve the in vitro potency of the c-Src inhibitor 1a and to address its hERG liability, a structure-activity study was carried out, focusing on two regions of the lead compound. The blockade of the delayed cardiac current rectifier K(+) (I(Kr)) channel was overcome by replacing the ethylenediamino group with an amino alcohol group at the 7-position. In addition, modifying the substituents at the 5-position and the side chain groups on the amino alcohols at the 7-position enhanced the intracellular c-Src inhibitory activity and increased central nervous system (CNS) penetration. In the present study, 6l exhibited significant in vivo efficacy in a middle cerebral artery (MCA) occlusion model in rats.


Assuntos
Bloqueadores dos Canais de Potássio/farmacologia , Pirazóis , Pirimidinas , Quinases da Família src/antagonistas & inibidores , Animais , Técnicas de Química Combinatória , Artéria Cerebral Média/efeitos dos fármacos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Pirazóis/farmacologia , Pirimidinas/síntese química , Pirimidinas/química , Pirimidinas/farmacologia , Ratos
6.
Breast ; 17(1): 27-35, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17716895

RESUMO

We conducted a case-control study to examine the relationship between breast density (BD) on mammography and breast cancer risk for postmenopausal Japanese women. The mammograms (205 cases and 223 controls) were classified by two doctors employing Wolfe's classification and used to measure BD with original computer software. A weak relationship between breast cancer risk and the parenchymal pattern of Wolfe's classification was found. The BD measured with the computer software, however, showed a significant relationship with breast cancer risk. Analysis after adjustment for epidemiologic factors showed that women in the quintile with the highest BD had a 3.02 times higher risk of breast cancer than those in the quintile with the lowest density. Since mammographic BD is clearly associated with breast cancer risk for postmenopausal Japanese women, our software can be expected to become a useful tool for objective risk assessment of breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Mamografia/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Japão , Pessoa de Meia-Idade , Pós-Menopausa , Análise de Regressão , Reprodutibilidade dos Testes , Medição de Risco
7.
Artigo em Inglês | MEDLINE | ID: mdl-18002083

RESUMO

At excision operations of a breast tumor, a navigation to display three-dimensional models during the operations is demanded to grasp a position and a size of the tumor, and to decide an area of the excision. Speckle noises which are characteristic of an ultrasonic image are caused by interference of sound waves. The noises cause a low resolution of a region of interest (ROI), and those are obstacle of constructing recognizable three-dimensional image. To reconstruct a three-dimensional model from two-dimensional ultrasonic tomograms, a speckle reduction and a contour extraction of the ROI are demanded. The purpose of this study is a contour extraction of a ROI on ultrasonic images. An active contour model using a gradient vector flow was employed. The contour of a lesion area of the ultrasonic images which speckle are reduced was extracted.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imageamento Tridimensional/métodos , Modelos Biológicos , Ultrassonografia Mamária , Feminino , Humanos , Ultrassonografia Mamária/métodos
8.
Artigo em Inglês | MEDLINE | ID: mdl-18002411

RESUMO

Speckle noise is indispensable get from ultrasound image. In general tends to reduce the image resolution and contrast. In addition to the doctor diagnosis, is lacking for judgment accuracy. This paper is reduced the speckle noise and enhanced boundary of a tumor in the medical ultrasound images. The proposed method is valuated using numerical phantom simulating ultrasound B-mode images, and the effect is confirmed by applying to medical ultrasound images. Therefore, some important features such as tissue boundaries and small tumors may be overlooked. A cellular neural network which is a kind of recurrent neural network can deal with images by the weight of neurons called a cell. It could be obtained more detail images recognition compared with the previous studies. Determination template parameters of the cellular neural network for ultrasound image processing are discussed. The experimental results show effectiveness of applying the proposed method to boundary enhancement and the speckle noise reduction of medical ultrasound image.


Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Ultrassonografia/métodos , Algoritmos , Artefatos , Desenho de Equipamento , Humanos , Interpretação de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador , Modelos Estatísticos , Neoplasias/metabolismo , Rede Nervosa , Redes Neurais de Computação , Neurônios/metabolismo , Processamento de Sinais Assistido por Computador , Técnica de Subtração , Ultrassom , Ultrassonografia/instrumentação
9.
Chem Pharm Bull (Tokyo) ; 55(6): 881-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17541186

RESUMO

We synthesized a series of novel 2-anilinopyrazolo[1,5-a]pyrimidine derivatives and evaluated their ability to inhibit c-Src kinase; 7-(2-amino-2-methylpropylamino)-5-cyclopropyl-2-(3,5-dimethoxyphenylamino)pyrazolo[1,5-a]pyrimidine-3-carboxamide 7o and 7-(2-amino-2-methylpropylamino)-2-(3,5-dimethoxyphenylamino)-5-methylpyrazolo[1,5-a]pyrimidine-3-carboxamide 7f showed potent inhibitory activity. Compound 7f inhibited c-Src selectively and exhibited satisfactory central nervous system (CNS) penetration. Furthermore, 7f.HCl reduced the infarct volume in vivo in a rat middle cerebral artery (MCA) occlusion model when administrated intraperitoneally.


Assuntos
Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/química , Acidente Vascular Cerebral/tratamento farmacológico , Quinases da Família src/antagonistas & inibidores , Animais , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Masculino , Modelos Moleculares , Inibidores de Proteínas Quinases/química , Pirimidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Espectrofotometria Infravermelho
10.
Bioorg Med Chem ; 15(2): 868-85, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17095233
11.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 62(1): 136-44, 2006 Jan 20.
Artigo em Japonês | MEDLINE | ID: mdl-16456515

RESUMO

PURPOSE: In percutaneous vertebroplasty (PVP), intraosseous venography is performed using water-soluble ionic iodinated contrast media (iodine contrast media) before injecting bone cement. However, because of contrast medium remaining in the fractured cleft, we experienced the persistence of intravertebral opacification that obscured visualization of the cement under X-ray fluoroscopy. To solve this problem, we examined carbon dioxide (CO(2)) as a contrast medium. METHODS: We measured the contrast of iodine contrast media and CO(2) and performed a subjective assessment of imaging by enforcing intraosseous venography by changing the tube voltage and image intensifier (I.I.) entrance dose in a bone sample of a cadaver using iodine contrast media and CO(2). In vivo study, we performed a subjective assessment of images obtained by intraosseous venography using CO(2) under two kinds of X-ray views. RESULTS: We determined that the contrast of CO(2) is 1/6-1/7.5 that of iodine contrast media, and that CO(2) fluctuates less in its contrast value with changes in tube voltage. In our assessment of the image of the bone sample, CO(2) performed worse that iodine contrast media. However, if the I.I. entrance dose is kept above 2.5 microGy/F, CO(2) is considered to be of clinical use. In the clinical image assessment, the best conditions were an image collection rate of 7.5 F/S and matrix of 1024 x 1024. CONCLUSIONS: CO(2) did not cause any obstacles when we injected bone cement, and its I.I. entrance dose, image collection rate, and matrix size indicate that it can be used for intraosseous venography.


Assuntos
Dióxido de Carbono , Meios de Contraste , Flebografia/métodos , Radiografia Intervencionista/métodos , Coluna Vertebral/irrigação sanguínea , Cimentos Ósseos/uso terapêutico , Dióxido de Carbono/administração & dosagem , Meios de Contraste/administração & dosagem , Fixação Interna de Fraturas/métodos , Iodo , Fraturas da Coluna Vertebral/terapia
12.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 2048-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17282629

RESUMO

The artifacts caused by various factors, EOG (electrooculogram), blink and EMG (electromyogram), in EEG (Electroencephalogram) signals increase the difficulty in analyzing them. In addition, EEG signals containing artifacts often cannot be used in analyzing them. So, it is useful and indispensable to eliminate the artifacts from EEG signals. In this paper, a neural network with non-recursive IIR (Infinite Impulse Response) filters are used to eliminate the artifacts from EEG signals. The proposed method is a new approach that is respect to slotting a non-recursive IIR filter into individual neurons of a neural network. First of all, in order to investigate the usefulness of the proposed method in eliminating the artifacts from EEG signals, we apply it to the artificial EEG signals that are weakly stationary process. As the result, the artifacts can be eliminated from EEG signals almost exactly using the proposed method, and it is suggested the proposed method should be useful in eliminating the artifacts from EEG signals.

13.
Artigo em Inglês | MEDLINE | ID: mdl-17271751

RESUMO

The artifacts caused by various factors, EOG (electrooculogram), blink and EMG (electromyogram), in EEG (electroencephalogram) signals increase the difficulty in analyzing them. In addition, EEG signals containing artifacts often cannot be used in analyzing them. So, it is useful and indispensable to eliminate the artifacts from EEG signals. A neural network with non-recursive 2nd order volterra filters is used to eliminate the artifacts from EEG signals. The proposed method is a new approach in respect to slotting a non-recursive 2nd order volterra filter into individual neurons of a neural network. First of all, in order to investigate the usefulness of the proposed method in eliminating the artifacts from EEG signals, we apply it to the artificial EEG signals mat are weakly stationary process. As the result, the artifacts can be eliminated from EEG signals almost exactly using the proposed method, and ft is suggested the proposed method should be useful in eliminating the artifacts from EEG signals.

14.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 1509-12, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271983

RESUMO

We discuss a new morphological operations using double structuring elements (DSEs) and apply them to image sharpening of ultrasound B-mode images with speckle pattern. The DSEs, a couple of two different structuring elements, varying with the local characteristics of the input image, yield an edge-sharpening effect. General single structuring element does not have the sharpening function. Our method improves contrast at the tissue boundary without speckle emphasis and does not generate overshoot nor undershoot around the boundary. We demonstrate its effectiveness in experiments using human thyroid images.

15.
Chirality ; 16(1): 13-21, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14628295

RESUMO

The absolute configuration of the chiral thyroid hormone analog KAT-2003 (+)-2, showing hypocholesterolemic activities, decreases of hepatic triglyceride contents with lowering cardiac side effects, and significant inhibitory effect for the second primary hepatocellular carcinoma, was determined as S by the (1)H NMR anisotropy method using a novel chiral auxiliary, 2-methoxy-2-(1-naphtyl)propionic acid (MalphaNP acid).


Assuntos
Tri-Iodotironina/análogos & derivados , Animais , Anisotropia , Anticolesterolemiantes/química , Anticolesterolemiantes/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Propionatos , Estereoisomerismo , Tri-Iodotironina/química , Tri-Iodotironina/farmacologia
16.
Chem Pharm Bull (Tokyo) ; 51(2): 221-3, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12576663

RESUMO

Chiral bis(alpha, alpha-diphenyl-2-pyrrolidinemethanol) carbonate (DPP(2).H(2)CO(3)) is a useful asymmetric auxiliary for the asymmetric borane reduction of prochiral ketones. Chiral DPP(2).H(2)CO(3) is recoverable from the reaction and directly reusable for the reaction. The intermediate of KUR-1246, which we are developing as a new uterine relaxant, was synthesized using the methodology.


Assuntos
Boranos/química , Pirrolidinas/química , Boranos/metabolismo , Carbonatos/química , Carbonatos/metabolismo , Metanol/química , Metanol/metabolismo , Oxirredução , Pirrolidinas/metabolismo , Estereoisomerismo
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