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1.
Oral Dis ; 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36825457

RESUMO

OBJECTIVES: To identify the molecular etiology of distinct dental anomalies found in eight Thai patients and explore the mutational effects on cellular functions. MATERIALS AND METHODS: Clinical and radiographic examinations were performed for eight patients. Whole exome sequencing, mutant protein modelling, qPCR, western blot analysis, scratch assays, immunofluorescence, confocal analysis, in situ hybridization, and scanning electron micrography of teeth were done. RESULTS: All patients had molars with multiple supernumerary cusps, single-cusped premolars, and a reduction in root number. Mutation analysis highlighted a heterozygous c.865A>G; p.Ile289Val mutation in CACNA1S in the patients. CACNA1S is a component of the slowly inactivating L-type voltage-dependent calcium channel. Mutant protein modeling suggested that the mutation might allow leakage of Ca2+ or other cations, or a tightening, to restrict calcium flow. Immunohistochemistry analysis showed expression of Cacna1s in the developing murine tooth epithelium during stages of crown and root morphogenesis. In cell culture, the mutation resulted in abnormal cell migration of transfected CHO cells compared to wildtype CACNA1S, with changes to the cytoskeleton and markers of focal adhesion. CONCLUSIONS: The malformations observed in our patients suggest a role for calcium signaling in organization of both cusps and roots, affecting cell dynamics within the dental epithelium.

4.
Colorectal Dis ; 18(8): 795-802, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26784017

RESUMO

AIM: Sessile serrated adenomas/polyps (SSA/Ps) have been proposed as precursors of colorectal cancer. The aims of this investigation were to compare the endoscopic findings of SSA/Ps with those of other serrated lesions and to compare the histological findings of SSA/Ps with those of conventional adenomas. METHOD: We retrospectively reviewed colonoscopy records at our institution from 1984 to 2013 and identified cases of endoscopically or surgically resected conventional adenomas and serrated lesions, including SSA/Ps, hyperplastic polyps (HPs) and traditional serrated adenomas (TSAs). The colonoscopic findings of SSA/Ps were compared with those of the other two serrated lesions and histological findings were compared among all groups of lesions. RESULTS: There were 79 HPs in 68 patients, 77 SSA/Ps in 63 patients, 167 TSAs in 145 patients and 6324 conventional adenomas in 4129 patients. The inverted type and flat-elevated type were more frequent among SSA/Ps than among the other two types of serrated lesions. Magnifying colonoscopy revealed that a round and open pit pattern, expanded crypt openings and varicose microvascular vessels were more frequently observed among SSA/Ps than among the other types. The incidence of high-grade dysplasia or carcinoma among SSA/Ps (13.0%) was significantly higher than that among HPs (0%, P < 0.001) and equivalent to that among conventional adenomas (12.3%). CONCLUSION: SSA/Ps have colonoscopic features distinct from those of HPs and TSAs. The malignant potential of SSA/Ps seems to be equal to that of conventional adenomas.


Assuntos
Adenocarcinoma/patologia , Adenoma/patologia , Pólipos do Colo/patologia , Colonoscopia , Neoplasias Colorretais/patologia , Microvasos/patologia , Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/complicações , Adenoma/irrigação sanguínea , Adenoma/complicações , Idoso , Colo/patologia , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/complicações , Feminino , Humanos , Hiperplasia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
J Anim Physiol Anim Nutr (Berl) ; 100(4): 715-22, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26849275

RESUMO

The effect of mannitol on bone-related mineral absorption and retention and the mechanism was investigated in this study. Fourteen 8-week-old male Wistar rats in experiment 1 and same number and age cecectomized Wistar male rats in experiment 2 were divided into two subgroups of seven animals, respectively, fed diets containing 0 or 4% mannitol for 28 days. Mineral balance tests were determined twice during days 8-12 and days 22-26, and the rats were slaughtered on day 28 both in experiment 1 and experiment 2. The whole caecum and colon were collected with the content to analyse tissue weight, content weight, content's pH and moisture, organic acids' concentration and mineral levels. In experiment 1, Ca absorption and retention and Mg absorption were significantly increased by mannitol feeding during days 8-12. Caecal total weight, tissue weight and content weight were increased, the pH of caecum and colon was reduced, and the concentrations of caecal short-chain fatty acids (SCFAs) were modified by mannitol feeding. In experiment 2, during days 8-12 and days 22-26, Ca absorption and retention were significantly lowered by mannitol feeding in cecectomized rats; however, mannitol feeding decreased Mg absorption during days 8-12, but did not impact Mg retention. Colonic total weight, tissue weight and content weight were significantly increased, and colonic pH was reduced by mannitol feeding. In conclusion, dietary mannitol increased the absorption of Ca and Mg and the caecum markedly contributed to this promoting effect of mannitol.


Assuntos
Cálcio/farmacocinética , Suplementos Nutricionais , Magnésio/farmacocinética , Manitol/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cálcio/administração & dosagem , Dieta , Fezes/química , Magnésio/administração & dosagem , Masculino , Manitol/administração & dosagem , Ratos , Ratos Wistar
8.
Oral Dis ; 20(3): e49-56, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23679350

RESUMO

OBJECTIVE: Periodontitis is a chronic inflammatory disease of the tissues supporting the teeth and is caused by subgingival plaque. Systemic increases in reactive oxygen species are involved in pathogenesis of periodontitis. This study addressed the relationship between levels of serum oxidative stress and antibodies against putative periodontopathic bacteria and their association with periodontal conditions, in a community-based study. SUBJECTS AND METHODS: Serum samples were measured for reactive oxygen metabolite (ROM) levels and anti-oxidant capacity. The serum levels of immunoglobulin G (IgG) antibodies to Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Aggregatibacter actinomycetemcomitans (Aa), and Eikenella corrodens (Ec) were determined by ELISA. RESULTS: The participants with greater clinical attachment loss had higher serum ROM levels and IgG antibody titers to Pg. Serum ROM levels were positively correlated with antibody titers to Pg, Pi, and Ec. When the participants with greater probing pocket depth and clinical attachment loss were used as the dependent variables, high ROM levels showed a statistically significant associations in multivariate logistic analyses; the adjusted odds ratios were 2.9 (95% confidence interval = 1.0-8.5) and 6.0 (95% confidence interval = 2.0-17.6), respectively. CONCLUSIONS: It was concluded that an increased oxidative stress may be detrimental to periodontitis in Japanese community-dwelling adults.


Assuntos
Anticorpos Antibacterianos/sangue , Imunoglobulina G/sangue , Estresse Oxidativo , Periodontite/microbiologia , Idoso , Estudos Transversais , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade
9.
Nat Commun ; 15(1): 7528, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237494

RESUMO

High-intensity, short-pulse lasers are crucial for generating energetic electrons that produce high-energy-density (HED) states in matter, offering potential applications in igniting dense fusion fuels for fast ignition laser fusion. High-density targets heated by these electrons exhibit spatially non-uniform and highly transient conditions, which have been challenging to characterize due to limitations in diagnostics that provide simultaneous high spatial and temporal resolution. Here, we employ an X-ray Free Electron Laser (XFEL) to achieve spatiotemporally resolved measurements at sub-micron and femtosecond scales on a solid-density copper foil heated by laser-driven fast electrons. Our X-ray transmission imaging reveals the formation of a solid-density hot plasma localized to the laser spot size, surrounded by Fermi degenerate, warm dense matter within a picosecond, and the energy relaxation occurring within the hot plasma over tens of picoseconds. These results validate 2D particle-in-cell simulations incorporating atomic processes and provide insights into the energy transfer mechanisms beyond current simulation capabilities. This work significantly advances our understanding of rapid fast electron heating and energy relaxation in solid-density matter, serving as a key stepping stone towards efficient high-density plasma heating and furthering the fields of HED science and inertial fusion energy research using intense, short-pulse lasers.

11.
Nat Genet ; 17(4): 393-8, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9398839

RESUMO

Autoimmune polyglandular syndrome type I (APS 1, also called APECED) is an autosomal-recessive disorder that maps to human chromosome 21q22.3 between markers D21S49 and D21S171 by linkage studies. We have isolated a novel gene from this region, AIRE (autoimmune regulator), which encodes a protein containing motifs suggestive of a transcription factor including two zinc-finger (PHD-finger) motifs, a proline-rich region and three LXXLL motifs. Two mutations, a C-->T substitution that changes the Arg 257 (CGA) to a stop codon (TGA) and an A-->G substitution that changes the Lys 83 (AAG) to a Glu codon (GAG), were found in this novel gene in Swiss and Finnish APECED patients. The Arg257stop (R257X) is the predominant mutation in Finnish APECED patients, accounting for 10/12 alleles studied. These results indicate that this gene is responsible for the pathogenesis of APECED. The identification of the gene defective in APECED should facilitate the genetic diagnosis and potential treatment of the disease and further enhance our general understanding of the mechanisms underlying autoimmune diseases.


Assuntos
Clonagem Molecular/métodos , Poliendocrinopatias Autoimunes/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Cromossomos Humanos Par 21 , Análise Mutacional de DNA , Haplótipos , Humanos , Dados de Sequência Molecular , Especificidade de Órgãos/genética , RNA Mensageiro/biossíntese , Fatores de Transcrição/biossíntese , Fatores de Transcrição/química , Dedos de Zinco/genética , Proteína AIRE
12.
Nat Genet ; 27(1): 59-63, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11137999

RESUMO

Approximately 50% of childhood deafness is caused by mutations in specific genes. Autosomal recessive loci account for approximately 80% of nonsyndromic genetic deafness. Here we report the identification of a new transmembrane serine protease (TMPRSS3; also known as ECHOS1) expressed in many tissues, including fetal cochlea, which is mutated in the families used to describe both the DFNB10 and DFNB8 loci. An 8-bp deletion and insertion of 18 monomeric (approximately 68-bp) beta-satellite repeat units, normally present in tandem arrays of up to several hundred kilobases on the short arms of acrocentric chromosomes, causes congenital deafness (DFNB10). A mutation in a splice-acceptor site, resulting in a 4-bp insertion in the mRNA and a frameshift, was detected in childhood onset deafness (DFNB8). This is the first description of beta-satellite insertion into an active gene resulting in a pathogenic state, and the first description of a protease involved in hearing loss.


Assuntos
DNA Satélite/genética , Surdez/congênito , Surdez/enzimologia , Genes Recessivos/genética , Proteínas de Membrana , Mutagênese Insercional/genética , Proteínas de Neoplasias , Serina Endopeptidases/genética , Adulto , Idade de Início , Sequência de Bases , Criança , Consanguinidade , Mapeamento de Sequências Contíguas , Análise Mutacional de DNA , Surdez/epidemiologia , Surdez/genética , Éxons/genética , Feminino , Mutação da Fase de Leitura/genética , Humanos , Hibridização in Situ Fluorescente , Israel , Masculino , Dados de Sequência Molecular , Paquistão , Linhagem , Sítios de Splice de RNA/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Alinhamento de Sequência , Serina Endopeptidases/metabolismo
13.
Rev Sci Instrum ; 94(3): 033511, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37012804

RESUMO

High-power, short-pulse laser-driven fast electrons can rapidly heat and ionize a high-density target before it hydrodynamically expands. The transport of such electrons within a solid target has been studied using two-dimensional (2D) imaging of electron-induced Kα radiation. However, it is currently limited to no or picosecond scale temporal resolutions. Here, we demonstrate femtosecond time-resolved 2D imaging of fast electron transport in a solid copper foil using the SACLA x-ray free electron laser (XFEL). An unfocused collimated x-ray beam produced transmission images with sub-micron and ∼10 fs resolutions. The XFEL beam, tuned to its photon energy slightly above the Cu K-edge, enabled 2D imaging of transmission changes induced by electron isochoric heating. Time-resolved measurements obtained by varying the time delay between the x-ray probe and the optical laser show that the signature of the electron-heated region expands at ∼25% of the speed of light in a picosecond duration. Time-integrated Cu Kα images support the electron energy and propagation distance observed with the transmission imaging. The x-ray near-edge transmission imaging with a tunable XFEL beam could be broadly applicable for imaging isochorically heated targets by laser-driven relativistic electrons, energetic protons, or an intense x-ray beam.

15.
J Nanosci Nanotechnol ; 12(5): 3751-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22852303

RESUMO

Zinc oxide (ZnO) nanotip thin films were prepared on ZnO coated nanocrystalline ITO/glass substrates by hydrothermal method. In order to obtain the ZnO nanotip arrays with high aspect ratio, the experimental conditions were optimized. The scanning electron microscope images showed that the surface morphology of ZnO thin films could be easily manipulated by changing the seed layer thickness and growth time. The ZnO nanotip thin films were grown epitaxially on ZnO seed layer coated ITO/glass substrates. The surface morphology of ZnO thin films on ITO/glass substrate changed from nanorods with a flat-top end to nanotips as the growth time was increased from 3 to 15 h. The ZnO thin films prepared under these deposition conditions were highly oriented along (002) direction. The as-prepared sample (15 h) was annealed at different temperatures (30, 100, 150, and 270 degrees C). The surface morphologies of annealed ZnO thin films did not show any remarkable change and the best crystallinity was observed at 100 degrees C. The photoluminescence spectra showed that the near band edge emission shifted to shorter wavelength as the annealing temperature was increased from 30 to 270 degrees C, it was due to the intrinsic stress in the films. This was confirmed by X-ray diffraction analyses. NPB thin films were prepared on ITO/clay and ITO/glass substrates by thermal evaporation method. The electrical properties of Ag/NPB/ITO/Clay showed the Ohmic characteristics (J proportional V(1.0)). The J-V characteristic of Ag/NPB/PMMA/ZnO/ITO/Glass showed good rectification behaviour with a diode-ideality factor of 1.36.

16.
Rev Sci Instrum ; 93(6): 063505, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778032

RESUMO

The shock ignition (SI) approach to inertial confinement fusion is a promising scheme for achieving energy production by nuclear fusion. SI relies on using a high intensity laser pulse (≈1016 W/cm2, with a duration of several hundred ps) at the end of the fuel compression stage. However, during laser-plasma interaction (LPI), several parametric instabilities, such as stimulated Raman scattering and two plasmon decay, nonlinearly generate hot electrons (HEs). The whole behavior of HE under SI conditions, including their generation, transport, and final absorption, is still unclear and needs further experimental investigation. This paper focuses on the development of an experimental platform for SI-related experiments, which simultaneously makes use of multiple diagnostics to characterize LPI and HE generation, transport, and energy deposition. Such diagnostics include optical spectrometers, streaked optical shadowgraph, an x-ray pinhole camera, a two-dimensional x-ray imager, a Cu Kα line spectrometer, two hot-electron spectrometers, a hard x-ray (bremsstrahlung) detector, and a streaked optical pyrometer. Diagnostics successfully operated simultaneously in single-shot mode, revealing the features of HEs under SI-relevant conditions.

18.
Community Dent Health ; 28(1): 29-33, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21485231

RESUMO

OBJECTIVES: To determine whether children advised by a pediatrician to take sports drinks consume them more frequently than do other children and whether these children have an increased risk of dental caries. METHODS: The subjects were 522 mother/child pairs who attended a dental checkup for 3-year-olds at one of ten community health centers in Nagasaki, Japan. Pearson's chi-square test was used to compare the prevalence of children with or without dental caries according to child-related variables. Multiple logistic regression was performed to assess the relationship between the presence of dental caries and child-related variables taken from a dental checkup and a questionnaire. RESULTS: A high frequency of sports drink consumption was strongly associated with dental caries in children. The highest proportion of mothers answered that they were advised by a pediatrician to give sports drinks to their children. However, these children consumed sports drinks significantly less frequently than did children who did so for reasons other than pediatrician recommendations. In addition, these children were significantly less likely to have dental caries than were children who consumed sports drinks for otherreasons. CONCLUSIONS: Pediatrician-recommended consumption of sports drinks does not lead to more frequent consumption of these beverages or to dental caries in 3-year-old children.


Assuntos
Bebidas/efeitos adversos , Cárie Dentária/etiologia , Pediatria , Distribuição de Qui-Quadrado , Pré-Escolar , Índice CPO , Cárie Dentária/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Modelos Logísticos , Masculino , Prevalência , Esportes , Inquéritos e Questionários
20.
J Cell Biol ; 137(5): 1041-56, 1997 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-9166405

RESUMO

The structure of membrane fusion intermediates between the A/PR/8(H1N1) strain of influenza virus and a liposome composed of egg phosphatidylcholine, cholesterol, and glycophorin was studied using quick-freezing electron microscopy. Fusion by viral hemagglutinin protein was induced at pH 5.0 and 23 degrees C. After a 19-s incubation under these conditions, small protrusions with a diameter of 10-20 nm were found on the fractured convex faces of the liposomal membranes, and small pits complementary to the protrusions were found on the concave faces. The protrusions and pits corresponded to fractured parts of outward bendings of the lipid bilayer or "microprotrusions of the lipid bilayer." At the loci of the protrusions and pits, liposomal membranes had local contacts with viral membranes. In many cases both the protrusions and the pits were aligned in regular polygonal arrangements, which were thought to reflect the array of hemagglutinin spikes on the viral surface. These structures were induced only when the medium was acidic with the virus present. Based on these observations, it was concluded that the microprotrusions of the lipid bilayer are induced by hemagglutinin protein. Furthermore, morphological evidence for the formation of the "initial fusion pore" at the microprotrusion was obtained. The protrusion on the convex face sometimes had a tiny hole with a diameter of <4 nm in the center. The pits transformed into narrow membrane connections <10 nm in width, bridging viruses and liposomes. The structures of the fusion pore and fusion neck with larger sizes were also observed, indicating growth of the protrusions and pits to distinct fusion sites. We propose that the microprotrusion of the lipid bilayer is a fusion intermediate induced by hemagglutinin protein, and suggest that the extraordinarily high curvature of this membrane structure is a clue to the onset of fusion. The possible architecture of the fusion intermediate is discussed with regard to the localization of intramembrane particles at the microprotrusion.


Assuntos
Membranas Intracelulares/ultraestrutura , Membranas Intracelulares/virologia , Lipossomos/metabolismo , Orthomyxoviridae/ultraestrutura , Ácidos , Animais , Embrião de Galinha , Técnica de Fratura por Congelamento , Hemaglutininas/análise , Hemaglutininas/metabolismo , Concentração de Íons de Hidrogênio , Membranas Intracelulares/metabolismo , Orthomyxoviridae/metabolismo
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