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1.
Nat Immunol ; 9(8): 908-16, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18604211

RESUMO

Autophagy, an evolutionally conserved homeostatic process for catabolizing cytoplasmic components, has been linked to the elimination of intracellular pathogens during mammalian innate immune responses. However, the mechanisms underlying cytoplasmic infection-induced autophagy and the function of autophagy in host survival after infection with intracellular pathogens remain unknown. Here we report that in drosophila, recognition of diaminopimelic acid-type peptidoglycan by the pattern-recognition receptor PGRP-LE was crucial for the induction of autophagy and that autophagy prevented the intracellular growth of Listeria monocytogenes and promoted host survival after this infection. Autophagy induction occurred independently of the Toll and IMD innate signaling pathways. Our findings define a pathway leading from the intracellular pattern-recognition receptors to the induction of autophagy to host defense.


Assuntos
Autofagia , Drosophila/imunologia , Drosophila/metabolismo , Imunidade Inata/imunologia , Listeria/imunologia , Peptidoglicano/metabolismo , Animais , Ácido Diaminopimélico , Drosophila/genética , Drosophila/crescimento & desenvolvimento , Listeria/citologia , Peptidoglicano/imunologia , Receptores Toll-Like/imunologia
2.
PLoS One ; 17(4): e0267677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35482658

RESUMO

Morphological changes in the upper airway and the resulting alteration in the nasal respiratory function after jawbone repositioning during orthognathic surgery have garnered attention recently. In particular, nasopharyngeal stenosis, because of the complex influence of both jaws, the effects of which have not yet been clarified owing to postero-superior repositioning of the maxilla, may significantly impact sleep and respiratory function, necessitating further functional evaluation. This study aimed to perform a functional evaluation of the effects of surgery involving maxillary repositioning, which may result in a larger airway resistance if the stenosis worsens the respiratory function, using CFD for treatment planning. A model was developed from CT images obtained preoperatively (PRE) and postoperatively (POST) in females (n = 3) who underwent maxillary postero-superior repositioning using Mimics and ICEM CFD. Simultaneously, a model of stenosis (STENOSIS) was developed by adjusting the severity of stenosis around the PNS to simulate greater repositioning than that in the POST. Inhalation at rest and atmospheric pressure were simulated in each model using Fluent, whereas pressure drop (ΔP) was evaluated using CFD Post. In this study, ΔP was proportional to airway resistance because the flow rate was constant. Therefore, the magnitude of ΔP was evaluated as the level of airway resistance. The ΔP in the airway was lower in the POST compared to the PRE, indicating that the analysis of the effects of repositioning on nasal ventilation showed that current surgery is appropriate with respect to functionality, as it does not compromise respiratory function. The rate of change in the cross-sectional area of the mass extending pharynx (α) was calculated as the ratio of each neighboring section. The closer the α-value is to 1, the smaller the ΔP, so ideally the airway should be constant. This study identified airway shapes that are favorable from the perspective of fluid dynamics.


Assuntos
Biologia Computacional , Hidrodinâmica , Maxila , Constrição Patológica , Feminino , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Faringe
3.
Oral Radiol ; 35(2): 91-100, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30484204

RESUMO

Magnetic resonance imaging (MRI) has become a critical tool for dental examination. MRI has many advantages over radiographic examination methods, including the lack of a requirement for patient exposure and the ability to capture high-contrast images of various tissue and organ types. However, MRI also has several limitations, including long examination times and the existence of metallic or motion artifacts. A cardiac imaging method using cine sequences was developed in the 1990s. This technique allows for analysis of heart movement and functional blood flow. Moreover, this method has been applied in dentistry. Recent research involving 3 T MRI has led to the achievement of a temporal resolution of < 10 ms, surpassing the frame rate of typical video recording. The current review introduces the history and principles of the cine sequence method and its application to the oral and maxillofacial regions.


Assuntos
Imagem Cinética por Ressonância Magnética , Filmes Cinematográficos , Boca , Artefatos , Humanos , Imageamento por Ressonância Magnética , Boca/diagnóstico por imagem , Movimento
4.
Prog Orthod ; 19(1): 7, 2018 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-29457192

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) has been used to study configurations of speech organs in the resting state. However, MRI is sensitive to metals, and numerous types of metallic appliances, most of which have a large magnetic susceptibility, are used in orthodontic treatment and may cause severe artifacts on MRI. We have developed techniques for obtaining MRI movies of the oral region, to evaluate articulatory changes, especially movement of the tongue, palate, and teeth, pre- and post-orthodontic/orthognathic treatment. We evaluated the influence of artifacts caused by orthodontic appliances, including fixed retainers, metal brackets, and wires, on measurements in 3-T MRI movies. METHODS: Sixteen healthy young adults (nine males, seven females; average age, 27 years) with normal occlusion were recruited. Four types of customized maxillary and mandibular plates were prepared by incorporating one of the following into the plate: (a) nothing, (b) a fixed canine-to-canine retainer, (c) metal brackets for the anterior and molar teeth, or (d) clear brackets for the anterior teeth and metal brackets for molars. A 3-T MRI movie, in segmented cine mode, was generated for each plate condition while participants pronounced a vowel-consonant-vowel syllable (/asa/). The size of the artifact due to the metallic brackets was measured. The face size and orthodontically important anatomical structures, such as the velum, the hard palate, and the laryngeal ventricle, were also measured. RESULTS: A large artifact was observed over the entire oral region around orthodontic appliances, altering regional visibility. The velopharyngeal height was measured as significantly longer in the presence of metal brackets. The maximum artifact size due to a metallic bracket was > 8 cm. Our results show that even if it is possible to obtain the measurements of palate length, nasion to sella, and nasion to basion in individuals wearing metal brackets for molars, the measurements might be affected due to the presence of artifacts. CONCLUSIONS: Orthodontic appliances, including metallic materials, sometimes produce significant measurement error in speech evaluation using MRI movies, which often become invisible or distorted by metallic orthodontic appliances. When the distorted image is measured, caution should be exercised, as the measurement may be affected. Based on the study, it is concluded that orthodontists should not necessarily remove all metallic appliances before MRI examination because the influence varies among the appliances and should also know that a significant measurement error in speech evaluation using MRI movie may occur by image distortion caused by metallic artifacts.


Assuntos
Artefatos , Imageamento por Ressonância Magnética/métodos , Filmes Cinematográficos , Aparelhos Ortodônticos , Adulto , Feminino , Humanos , Masculino , Metais , Desenho de Aparelho Ortodôntico
5.
Biomed Res Int ; 2015: 126264, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26273584

RESUMO

OBJECTIVE: Different bony structures can affect the function of the velopharyngeal muscles. Asian populations differ morphologically, including the morphologies of their bony structures. The purpose of this study was to compare the velopharyngeal structures during speech in two Asian populations: Japanese and Thai. METHODS: Ten healthy Japanese and Thai females (five each) were evaluated with a 3-Tesla (3 T) magnetic resonance imaging (MRI) scanner while they produced vowel-consonant-vowel syllable (/asa/). A gradient-echo sequence, fast low-angle shot with segmented cine and parallel imaging technique was used to obtain sagittal images of the velopharyngeal structures. RESULTS: MRI was carried out in real time during speech production, allowing investigations of the time-to-time changes in the velopharyngeal structures. Thai subjects had a significantly longer hard palate and produced shorter consonant than Japanese subjects. The velum of the Thai participants showed significant thickening during consonant production and their retroglossal space was significantly wider at rest, whereas the dimensional change during task performance was similar in the two populations. CONCLUSIONS: The 3 T MRI movie method can be used to investigate velopharyngeal function and diagnose velopharyngeal insufficiency. The racial differences may include differences in skeletal patterns and soft-tissue morphology that result in functional differences for the affected structures.


Assuntos
Imagem Cinética por Ressonância Magnética/métodos , Palato/anatomia & histologia , Palato/fisiologia , Medida da Produção da Fala/métodos , Fala/fisiologia , Esfíncter Velofaríngeo/anatomia & histologia , Esfíncter Velofaríngeo/fisiologia , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Japão/etnologia , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Caracteres Sexuais , Tailândia/etnologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-25956219

RESUMO

OBJECTIVE: To develop a magnetic resonance imaging (MRI) movie to reveal the dynamic movement of articulators and teeth. STUDY DESIGN: Five healthy females with normal occlusion participated in this study. Various concentrations of MRI contrast media (ferric ammonium citrate [FAC]) were tested for visualization of teeth, according to facial markers and with the use of a gel. Custom-made circuitry was connected to synchronize pronunciation of fricative sounds (/asa/) with scans. Three gradient echo sequences (True fast imaging with steady state precession [true FISP], FISP, and fast low angle shot [FLASH]) with a segmented cine were tested with the use of repetition times (TRs) of 9 ms and 31.5 ms. The MRI movie images were superimposed over the boundaries of teeth. The images produced during pronunciation, using the two different TRs (9 ms and 31 ms), were compared to assess the position of the lips and the tongue. RESULTS: Images obtained using the FLASH sequence, with a TR of 9 ms or 31.5 ms, can be used for diagnostic purposes. A TR of 9 ms, with 161 continuous images acquired, produced the highest-quality images of teeth, with few artifacts present. Pronunciation of the consonant "s" was clearly discernable. CONCLUSIONS: Our 3-T MRI movie system, with a temporal resolution less than 9 ms, can provide detailed information pertaining to variations in speech or oropharyngeal function.


Assuntos
Imagem Cinética por Ressonância Magnética/métodos , Fala/fisiologia , Dente/anatomia & histologia , Adulto , Meios de Contraste , Feminino , Humanos , Modelos Dentários , Faringe/anatomia & histologia , Faringe/fisiologia , Projetos Piloto , Reprodutibilidade dos Testes , Língua/anatomia & histologia , Língua/fisiologia
7.
Intern Med ; 43(10): 986-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15575253

RESUMO

We detected Epstein-Barr virus (EBV) reactivation in a patient with mantle cell lymphoma (MCL). The patient, a 53-year-old Japanese man, had been referred to our hospital because of generalized lymphadenopathy, hepatosplenomegaly and lymphocytosis and gave a history of intense skin reactions to mosquito bites. The biopsied lymph node contained a monotonous proliferation of medium-sized lymphocytes with scant cytoplasm and slightly irregular nuclei that were CD5+, CD20+ and CD23-. Antibody titers of IgG against EBV viral capsid antigen and early antigen were increased, and EBV was detected in the lymphoma cells. This case may suggest a relationship between EBV and MCL.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Linfoma de Célula do Manto/complicações , Animais , Culicidae/imunologia , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Mordeduras e Picadas de Insetos/imunologia , Linfonodos/patologia , Doenças Linfáticas/etiologia , Linfocitose/etiologia , Masculino , Pessoa de Meia-Idade , Pele/patologia
8.
J Nippon Med Sch ; 70(6): 509-14, 2003 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-14685291

RESUMO

Remnants of cardiomyocytes showing coagulation necrosis in the scars caused by myocardial infarction were histopathologically studied. Among 305 autopsy cases of acute and/or healed myocardial infarction, 8 cases (7 men, 1 woman, ages 62 - 87 years, mean age 72.1) had masses of cardiomyocytes with coagulation necrosis at the center of the infarction scars more than 3 weeks (21 to 79 days) after the attack of myocardial infarction. All these cases had transmural infarction and more than 80% of the wall thickness of the left ventricle was involved in the infarction. No polymorphonuclear leukocytic infiltration or granulation tissue was found in the necrotic area, but macrophages were observed in the peripheral area adjacent to the scar tissue. Immunohistochemical staining for myoglobin showed no reaction in remnant necrotic cells or pericellular interstitium, which was similar to findings in the necrotic area more than 4 days after the infarction. These findings are important in the pathological diagnosis to distinguish remnant necrosis from acute necrosis, because 4 out of 8 present cases (50%) were misdiagnosed as acute myocardial infarction that superimposed on the previous old infarction.


Assuntos
Infarto do Miocárdio/patologia , Miocárdio/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Necrose
9.
Orthodontics (Chic.) ; 14(1): e222-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23646334

RESUMO

A plate that incorporates a Ti-Ni alloy wire can rapidly correct scissors bite. This article describes its use in the successful treatment of scissors bite. A female patient aged 7 years, 5 months with mixed dentition presented with a Class I molar relationship, Class I skeletal pattern, and average Frankfort-mandibular plane angle. The maxillary right central incisor was in a crossbite. A unilateral posterior scissors bite was also present on the left side. The plate was fitted and prescribed for nighttime wear. Positive overjet was achieved after 1 month of treatment. The posterior scissors bite was corrected after 3 months of treatment, and the midline shift was ameliorated. Because a Ti-Ni wire maintained a weak continuous force, the treatment period was minimized.


Assuntos
Ligas Dentárias/química , Má Oclusão/terapia , Níquel/química , Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos Removíveis , Fios Ortodônticos , Titânio/química , Criança , Dentição Mista , Feminino , Seguimentos , Humanos , Incisivo/patologia , Má Oclusão Classe I de Angle/terapia , Sobremordida/terapia , Planejamento de Assistência ao Paciente , Fatores de Tempo , Técnicas de Movimentação Dentária/instrumentação , Resultado do Tratamento
10.
Front Physiol ; 3: 233, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22754541

RESUMO

INTRODUCTION: The present study was designed to clarify whether the bilateral cooperation in the human periodontal-masseteric reflex (PMR) differs between central incisors and canines. METHODS: Surface array electrodes were placed on the bilateral masseter muscles to simultaneously record the firing activities of single motor units from both sides in seven healthy adults. During light clenching, mechanical stimulation was applied to the right maxillary central incisor and canine to evoke the PMR. Unitary activity was plotted with respect to the background activity and firing frequency. The slope of the regression line (sRL) and the correlation coefficient (CC) between the central incisor and canine and the lateral differences between these values were compared. RESULTS: There were significant differences in the sRL and CC, as well as lateral differences, between the central incisor- and canine-driven PMR. DISCUSSION: These results suggest that the PMR differs depending on both the tooth position and laterality.

11.
Eur Biophys J ; 37(7): 1167-74, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18330555

RESUMO

Photosynthetic reaction center (RC) pigment protein complex converts the free energy of light into chemical potential of charge pairs with extremely high efficiency. A transient phase in the absorption spectrum in the sub-millisecond time scale is expected to be especially important to examine the conformational gating model of the Q(A)Q(B) to Q(A)Q(B) (here Q(A )and Q(B) are the primary and secondary quinone type electron acceptors, respectively) electron transport. Essential kinetic components at few tens of microseconds scale and at around 200 microseconds have been suggested. We investigated the conformation change of RCs using heterodyne detection of the laser-induced transient grating method. An about 25 microseconds dynamics was observed, which coincides with the one described by the conformational gating model and possibly related to the nonadiabatic intrinsic Q(A)Q(B) to Q(A)Q(B) electron transport. The relative intensity of this component decreased with increasing quinone concentration indicating an initial (P+Q(A))1 or a relaxed (P+Q(A))2 conformational substate. We did not find the decay component at few hundreds of microseconds time scale indicating that there is no large displacement in the RC structure if Q(B) is present. The diffusion coefficient of the RC/LDAO detergent micelles calculated from the kinetic component was D = 3.8 x 10(-11 ) m2/s that agrees fairly well with the number estimated from the Einstein-Stokes relationship, and relates to a hydrodynamic diameter of 11.4 nm of the RC in LDAO micellar solution.


Assuntos
Lasers , Complexo de Proteínas do Centro de Reação Fotossintética/química , Transporte de Elétrons , Cinética , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Conformação Proteica , Prótons , Análise Espectral
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