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1.
Br Poult Sci ; 64(1): 47-55, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36129068

RESUMO

1. This study assessed 1) the effects of Paracoccus carotinifaciens supplementation containing high astaxanthin levels on egg production performance and quality, 2) dynamics of carotenoids levels in the egg yolk and 3) taste of astaxanthin-rich egg yolk.2. Laying hens were fed diets containing different levels of P. carotinifaciens-derived astaxanthin (ASX; 0, 2, 4, 8, or 16 ppm) for 28 d (experiment 1) or a diet containing 16 ppm astaxanthin for 28 d followed by a 0 ppm astaxanthin diet for 28 days (experiment 2).3. Production performance, egg quality and egg yolk carotenoid levels were examined in experiment 1 (Ex1) and the dynamics of egg yolk carotenoid levels and egg yolk taste in experiment 2 (Ex2).4. ASX supplementation did not affect production performance or egg quality. ASX levels in the egg yolk became saturated after seven days of 16 ppm supplementation and decreased to less than one-tenth of the saturated levels seven days after supplementation cessation. Supplementation with 16 ppm ASX for 28 d did not affect egg yolk taste.5. Supplementation resulted in the production of ASX-rich eggs for a brief period without affecting production performance, egg quality or taste. Understanding the time taken for the incorporation of ASX into egg yolks is beneficial for value-added egg production and may help in minimising supplementation costs.


Assuntos
Galinhas , Óvulo , Feminino , Animais , Gema de Ovo , Dieta/veterinária , Carotenoides , Suplementos Nutricionais/análise , Ração Animal/análise , Ovos/análise
2.
Epidemiol Infect ; 149: e244, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34726137

RESUMO

In June 2020, a large-scale food poisoning outbreak involving about 3000 elementary and junior high school students occurred in Yashio, Saitama, Japan. A school lunch was the only food stuff ingested by all of the patients. Escherichia coli serotype O7:H4 carrying the astA gene for enteroaggregative E. coli (EAggEC) heat-stable enterotoxin 1 (EAST1) was detected in faecal specimens from the patients, and sample inspection revealed its presence in a seaweed salad and red seaweed (Gigartina tenella) as one of the raw materials. Analysis of the antibiotic sensitivity of the isolates revealed resistance to ampicillin and cefotaxime. All isolates were confirmed to be of the same origin by pulsed-field gel electrophoresis after digestion with the restriction enzyme XbaI, and single nucleotide polymorphism analysis using whole genome sequencing. To our knowledge, this is the first report of a large-scale food poisoning caused by E. coli O7:H4, which lacks well-characterized virulence genes other than astA.


Assuntos
Surtos de Doenças , Escherichia coli/isolamento & purificação , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Toxinas Bacterianas/genética , Toxinas Bacterianas/isolamento & purificação , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Enterotoxinas/genética , Enterotoxinas/isolamento & purificação , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/isolamento & purificação , Contaminação de Alimentos , Serviços de Alimentação , Doenças Transmitidas por Alimentos/etiologia , Humanos , Japão/epidemiologia , Rodófitas , Sequenciamento Completo do Genoma
3.
Oper Dent ; 46(3): E117-E131, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34370032

RESUMO

OBJECTIVE: The aim of this study was to determine the flexural properties and surface characteristics of a structural colored resin composite after different finishing and polishing methods, in comparison to those of conventional resin composites. METHODS AND MATERIALS: A structural color resin composite, Omnichroma (OM, Tokuyama Corp, Chiyoda City, Tokyo, Japan), and two comparison resin composites, Filtek Supreme Ultra (FS, 3M, St Paul, MN, USA) and Tetric EvoCeram (TE, Ivoclar Vivadent, Schaan, Liechtenstein), were used. The flexural properties of the resin composites were determined in accordance with the ISO 4049 specifications. For surface properties, 70 polymerized specimens of each resin composite were prepared and divided into seven groups of 10. Surface roughness (Sa), gloss (GU), and surface free energy (SFE) were investigated after the following finishing and polishing methods. Three groups of specimens were finished with a superfine-grit diamond bur (SFD), and three with a tungsten carbide bur (TCB). After finishing, one of the two remaining groups was polished with a one-step silicone point (CMP), and the other with an aluminum oxide flexible disk (SSD). A group ground with SiC 320-grit was set as a baseline. RESULTS: The average flexural strength ranged from 116.6 to 142.3 MPa in the following order with significant differences between each value: FS > TE > OM. The average E ranged from 6.8 to 13.2 GPa in the following order with significant differences between each value: FS > TE > OM. The average R ranged from 0.77 to 1.01 MJ/mm3 in the following order: OM > FS > TE. The Sa values of the OM groups polished with CMP and SSD were found to be significantly lower than those of the other resin composites, regardless of the finishing method. The GU values appeared to be dependent on the material and the finishing method used. The OM specimens polished with SSD showed significantly higher GU values than those polished with CMP. Most of the resin composites polished with SSD demonstrated significantly higher γS values compared to the other groups. Extremely strong negative correlations between Sa and GU in the combined data from the three resin composites and each resin composite and between Sa and γS in the OM specimens were observed; GU showed a strong positive correlation with γS in the same material. CONCLUSION: These findings indicate that both flexural and surface properties are material dependent. Furthermore, the different finishing and polishing methods used in this study were observed to affect the Sa, GU, and SFE of the resin composites.


Assuntos
Polimento Dentário , Resistência à Flexão , Óxido de Alumínio , Resinas Compostas , Teste de Materiais , Propriedades de Superfície
4.
Oper Dent ; 46(3): 306-315, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34411249

RESUMO

PURPOSE: The present study evaluated the color-matching ability of a structural colored resin composite to compare it with resin composites employing pigments. METHODS AND MATERIALS: A structural colored resin composite (Omnichroma [OMC]), a supranano-filled resin composite (Estelite ∑ Quick [ELQ]), and a nano-filled resin composite (Filtek Supreme Ultra [FSU]) were used. Each resin composite was packed into a Teflon mold and pressed down with a clear strip under a glass slide. The specimens were light irradiated through the slide with a light-emitting diode curing unit. The thickness of the specimens (n=6) was measured with a digital caliper before being transferred to distilled water and stored at 37°C for 24 hours. The measurements of the optical characteristics of the specimens on a black-and-white background were performed using a spectrophotometer. D65 (CIE D65) was used as a light source for the spectrophotometer. Measurements were repeated three times for each specimen under each color-measurement condition, and average values for three same-shade specimens were calculated. One-way analysis of variance and Tukey post hoc tests were used (α=0.05). To determine its ability to match the color of artificial teeth, each shade of resin composite was placed in a cavity before performing color measurements. Using a spectrophotometer (CMS-35F S/C) with a flexible sensor, L*, a*, and b* values were obtained. RESULTS: The spectral reflectance curve of OMC showed that it reflected light wavelengths from 430-700 nm regardless of the background color and thickness of the specimens. The percentage of reflectance of ELQ decreased near wavelengths of 550-580 nm. Regarding the influence of background color on CIE L*, a*, b* values, the L* level showed significantly higher values for all tested materials with white backgrounds, and OMC was most affected by the difference in background color. However, a* values of ELQ and FSU were significantly higher with a black background than with a white background, and OMC showed a significantly higher value with a white background than with a black background. The b* values were higher with a white background than with a black background and were significantly higher for all three products, and these tendencies were much greater for ELQ and FSU. CONCLUSIONS: The ability of OMC to match the color of artificial teeth showed acceptable color compatibility, regardless of the shade of the artificial teeth and the depth of the cavity. However, ELQ and FSU showed reduced color compatibility, especially for a cavity depth of 3.0 mm. Excellent color matching ability was confirmed for the structural colored resin composite OMC, resulting in reduced color differences and therefore improving the esthetic appearance of the restoration, simplifying shade matching, and compensating for any color mismatch.


Assuntos
Resinas Compostas , Cárie Dentária , Cor , Humanos , Teste de Materiais , Espectrofotometria , Água
5.
Pharmazie ; 76(12): 611-613, 2021 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-34986958

RESUMO

The objectives of this study were as follows: 1) to compare the metabolic activities of endogenous compounds and their effects on dopamine formation and hydroxylation of steroid hormones, mediated by human cytochrome P450 (CYP), including CYP2C9.1 and CYP2C19, as well as the variants CYP2C9.2 (Arg144Cys) and CYP2C9.3 (Ile359Leu); and 2) to assess the effects of steroid hormones on the activities of CYP2C9.1, CYP2C9.2, and CYP2C19 to estimate the contribution of the CYP2C subfamily to metabolism and drug-drug interactions of endogenous compounds. Dopamine formation from p -tyramine and 6ß- and 21- (for progesterone) hydroxylation of testosterone, cortisol, and progesterone by CYP2C9 variants, CYP2C19, CYP2D6, and CYP3A4 were determined using HPLC. The effects of steroid hormones such as testosterone, cortisol, and progesterone on tolbutamide methyl hydroxylation mediated by CYP2C subfamily members were investigated. Only CYP2D6 catalyzed dopamine formation. The 6ß-hydroxylation activities of testosterone, cortisol, and progesterone catalyzed by CYP2C9 variants and CYP2D6 were less than 5% of those by CYP3A4. Although cortisol did not inhibit tolbutamide methyl hydroxylation catalyzed by CYP2C9.1, CYP2C9.2, or CYP2C19 and testosterone did not inhibit CYP2C19 activity, the reactions catalyzed by CY2C9.1 and CYP2C9.2 were inhibited by testosterone. The inhibition of progesterone by CYP2C19 was stronger than that by CYP2C9.1 and CYP2C9.2. CYP2C9.1 and CYP2C19 noncompetitively and competitively inhibited tolbutamide methyl hydroxylation with inhibition constants of 43.2 µM and 1.03 µM, respectively. Clinical interactions among endogenous compounds would vary within the CYP2C subfamily, although the contribution of the CYP2C subfamily may be of minor importance for dopamine formation and the detoxification (6ß-hydroxylation) of endogenous steroid hormones.


Assuntos
Citocromo P-450 CYP3A , Tolbutamida , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C19/metabolismo , Citocromo P-450 CYP2C9/genética , Citocromo P-450 CYP2C9/metabolismo , Citocromo P-450 CYP2D6 , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Dopamina/metabolismo , Humanos , Hidrocortisona , Hidroxilação , Microssomos Hepáticos/metabolismo , Progesterona/metabolismo , Esteroides , Testosterona/metabolismo , Tolbutamida/metabolismo
6.
BJOG ; 128(2): 329-335, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298518

RESUMO

OBJECTIVE: Fetal fractional limb volume has been proposed as a useful measure for quantifying fetal soft tissue development. The aim of this study was to investigate the growth of fractional arm volume (AVol) and fractional thigh volume (TVol) of fetuses with maternal gestational diabetes (GDM) compared with those of fetuses with normal glucose tolerance (NGT). We hypothesised fetal fractional limb volume would be larger in the GDM group than in the NGT group in late gestation. DESIGN: Exploratory observational study. SETTING: Saitama Municipal Hospital. SAMPLE: A total of 165 (125 NGT and 40 GDM) singleton Japanese pregnant women. METHODS: AVol and TVol were assessed between 20 and 37 weeks' gestation as cylindrical limb volumes based on 50% of the fetal humeral or femoral diaphysis length. Women were diagnosed as GDM based on the criteria of the Japan Society of Obstetrics and Gynecology. MAIN OUTCOME MEASURES: AVol and TVol were compared between women with NGT and those with GDM at each gestational age period (2-week intervals from 20 to 37 weeks' gestation). RESULTS: Overall, 287 ultrasound scans were performed (NGT group, 205 scans; GDM group, 82 scans). There was no significant difference of AVol between the groups before 32 weeks' gestation. AVol was significantly larger in the GDM group than in the NGT group after 32 weeks' gestation (P < 0.05). TVol was not statistically different between the groups across gestation. CONCLUSIONS: Detection of variations in fetal AVol may provide greater insight into understanding the origins of altered fetal body proportion in GDM. TWEETABLE ABSTRACT: AVol, but not TVol, is significantly larger in fetuses with GDM than in those with NGT after 32 weeks' gestation.


Assuntos
Braço/embriologia , Diabetes Gestacional/diagnóstico por imagem , Desenvolvimento Fetal/fisiologia , Feto/diagnóstico por imagem , Coxa da Perna/embriologia , Adulto , Braço/diagnóstico por imagem , Diáfises/diagnóstico por imagem , Diáfises/embriologia , Feminino , Fêmur/diagnóstico por imagem , Fêmur/embriologia , Idade Gestacional , Humanos , Úmero/diagnóstico por imagem , Úmero/embriologia , Japão , Tamanho do Órgão , Gravidez , Coxa da Perna/diagnóstico por imagem , Ultrassonografia Pré-Natal
7.
Opt Express ; 28(15): 22524-22539, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32752512

RESUMO

We report a thorough study of InGaN quantum wells spatially modified by varying the local misorientation of the GaN substrate prior to the epitaxial growth of the structure. More than 25 nm shift of emission wavelength was obtained, which is attributed to indium content changes in the quantum wells. Such an active region is promising for broadening of the emission spectrum of (In,Al,Ga)N superluminescent diodes. We observed that the light intensity changes with misorientation, being stable around 0.5° to 2° and decreasing above 2°. This relation can be used as a base for future device designing.

8.
Oper Dent ; 45(2): 183-195, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31567054

RESUMO

We attempted to determine the effect of universal adhesive application time on dentin bond performance in different etching modes based on shear bond strength (SBS) tests and surface free energy (SFE) measurements. The five universal adhesives used were Adhese Universal (AU), Clearfil Universal Bond Quick (CQ), G-Premio Bond (GP), Scotchbond Universal (SU), and Tokuyama Universal Bond (TU). Bovine dentin specimens were divided into four groups of 10 for each adhesive. SBS and SFE were determined after applying the following surface treatments: 1) self-etch (SE) mode with immediate air blowing after adhesive application (IA treatment), 2) SE mode with prolonged application time (PA treatment), 3) etch-and-rinse (ER) mode with IA treatment, and 4) ER mode with PA treatment. Bonded specimens were subjected to SBS testing. The SFE of adhesive-treated dentin surfaces was measured after rinsing with acetone and water. Three-way analysis of variance revealed that dentin SBS values (p<0.001) were significantly influenced by the factors of adhesive type and application duration, but the factor of pre-etching was not significant (p=0.985). The manufacturer's instructions require longer application times for AU and SU, which showed significantly lower SBS values in IA than in PA treatment in both etching modes. However, the difference in the other adhesives was not significant between the IA and PA treatments in either etching mode. The total SFE (γS) was dependent on the adhesive and etching mode. The γS value of the initial group (SiC paper ground group) at baseline was 69.5 (mN·m-1) and that of the pre-etching group at baseline was 30.6 (mN·m-1). For all the adhesives, γS in SE mode showed significantly higher values than in ER mode, regardless of the application time. In SE mode, almost all universal adhesives tested showed lower γS values in PA treatment than in IA treatment. For ER mode, all the adhesives showed significantly higher γS values than those of the pre-etching baseline, regardless of the application time. Most adhesives did not show any significant differences in γS values between IA and PA treatments, regardless of etching mode.


Assuntos
Colagem Dentária , Adesivos Dentinários , Condicionamento Ácido do Dente , Adesivos , Animais , Bovinos , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento
9.
Ultrasound Obstet Gynecol ; 55(2): 226-232, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31008542

RESUMO

OBJECTIVES: Tricuspid valve dysplasia (TVD) and Ebstein's anomaly (EA) diagnosed by fetal echocardiography vary greatly in terms of clinical severity and prognosis. The Celermajer index and Simpson-Andrews-Sharland (SAS) score have been reported previously for the prediction of prognosis in cases of TVD/EA; however, they do not take into account the hemodynamic impact of left ventricular (LV) function, which has recently been implicated as being important in the pathophysiology of TVD/EA. The aim of this study was to develop a novel scoring system that includes LV function for the prediction of perinatal death in fetuses diagnosed with TVD/EA. METHODS: The clinical records of 36 fetuses diagnosed prenatally with TVD/EA between 2000 and 2015 in our hospital were reviewed. Univariate analysis was used to assess the association between perinatal death (defined as death between 22 weeks' gestation and 4 weeks after delivery) and gestational age at diagnosis, cardiothoracic area ratio (CTAR), degree of pulmonary artery flow, direction of ductal flow, right-to-left ventricular diameter ratio, tricuspid regurgitation (TR) maximum velocity, Celermajer index, SAS score and LV-Tei index. A new prognostic score, the TRIPP score (TRIcuspid malformation Prognosis Prediction score), was developed using the parameters found to be associated significantly with perinatal death. The predictive value of this score was assessed in an additional nine fetuses diagnosed with TVD/EA. RESULTS: Thirty-six fetuses were diagnosed prenatally with TVD/EA, two of which were terminated, one was lost to follow-up and two died before 22 weeks' gestation. Of the 31 included fetuses, 10 (32%) died in the perinatal period. Univariate analysis demonstrated that TR maximum velocity was significantly lower (2.22 ± 0.17 m/s vs 3.26 ± 0.12 m/s; P < 0.001) and SAS score was significantly higher (5.7 ± 0.6 points vs 2.8 ± 0.4 points; P = 0.0014) in cases of perinatal death than in surviving fetuses. The degree of pulmonary artery flow and the direction of ductal flow were also associated significantly with perinatal death (P < 0.01 for both). Notably, LV-Tei index was significantly higher in cases of perinatal death than in surviving fetuses (0.81 ± 0.08 vs 0.50 ± 0.05; P < 0.001). In contrast, there was no significant difference in Celermajer index, CTAR or right-to-left ventricular diameter ratio. Finally, we established a novel combinatorial scoring system, the TRIPP score, including the four significant factors: TR maximum velocity, pulmonary artery flow, direction of ductal flow and LV-Tei index. The TRIPP score was found to predict efficiently perinatal mortality in fetuses with TVD/EA. CONCLUSIONS: Our novel combinatorial score of echocardiographic parameters, the TRIPP score, including LV-Tei index, is easy to measure and provides a good tool for the prediction of perinatal mortality in fetuses diagnosed prenatally with TVD/EA. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Regras de Decisão Clínica , Anomalia de Ebstein/diagnóstico , Ecocardiografia/métodos , Cardiopatias Congênitas/diagnóstico , Diagnóstico Pré-Natal/métodos , Insuficiência da Valva Tricúspide/diagnóstico , Anomalia de Ebstein/embriologia , Anomalia de Ebstein/mortalidade , Feminino , Idade Gestacional , Cardiopatias Congênitas/embriologia , Cardiopatias Congênitas/mortalidade , Humanos , Recém-Nascido , Morte Perinatal/etiologia , Mortalidade Perinatal , Valor Preditivo dos Testes , Gravidez , Prognóstico , Estudos Retrospectivos , Valva Tricúspide/embriologia , Insuficiência da Valva Tricúspide/embriologia , Insuficiência da Valva Tricúspide/mortalidade , Função Ventricular Esquerda
10.
Oper Dent ; 45(2): E91-E104, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31738697

RESUMO

The purpose of this study was to determine the influence of finishing and polishing methods on surface properties of bulk-fill resin composites through surface roughness (Ra) and surface free energy (SFE) measurements, and scanning electron microscopy (SEM) observations. Three bulk-fill resin composites, Tetric EvoCeram Bulk Fill (TB), Filtek Bulk Fill (FB), and Filtek Bulk Fill Flowable Restorative (FF), and two conventional resin composites, Clearfil AP-X (AP) and Estelite ∑ Quick (EQ) were used. Seventy cured specimens of each resin composite were prepared and divided into seven groups of 10 specimens. Ra, SFE measurements, and SEM observations were conducted after finishing and polishing procedures. Three groups of specimens were finished with a fine grit diamond bur (FDB), and three with a tungsten carbide bur (CBB). After finishing, one group from each type of finishing was polished with aluminum oxide flexible disks (SSD) and one group from each type of finishing was polished with diamond particles embedded in a silicone point (CMP). A baseline group of samples that were neither finished nor polished after removing the translucent strips from the surface was examined. Although the baseline group showed significantly lower Ra values than the other groups, most resin composites showed lower Ra values with CBB+SSD than with the other finishing and polishing groups. Among the tested resin composites, EQ showed significantly lower Ra values than the other resin composites, regardless of the finishing and polishing methods. On the other hand, AP showed significantly higher Ra values than the other resin composites in all finishing and polishing groups, apart from FB with FDB. For the finished specimens, most resin composites showed higher SFE values with CBB than with FDB. For the polished specimens, all the tested resin composites with CMP showed lower γS values than those with SSD, regardless of the finishing method. The baseline groups of TB and FB showed significantly lower SFE values than the other finished and polished groups. In the SEM observations, all the examined resin composites showed rougher surfaces after finishing with FDB than with CBB. However, when comparing the different polishing methods (CMP and SSD), surface smoothness appeared to be material dependent.


Assuntos
Polimento Dentário , Restauração Dentária Permanente , Óxido de Alumínio , Resinas Compostas , Diamante , Teste de Materiais , Microscopia Eletrônica de Varredura , Propriedades de Superfície
11.
Oper Dent ; 44(2): 188-199, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30106329

RESUMO

The purpose of this study was to determine the effect of different adhesive application methods and etching modes on the dentin bond durability of universal adhesives under thermal cycling (TC). All-Bond Universal (Bisco), Adhese Universal (Ivoclar Vivadent), and Scotchbond Universal (3M ESPE) were used as adhesives. In total, 600 bovine teeth with exposed dentin were divided into 12 groups according to the type of adhesive and subjected to the following bonding procedures: 1) etch-and-rinse mode with active application; 2) etch-and-rinse mode with inactive application; 3) self-etch mode with active application; and 4) self-etch mode with inactive application. Bonded specimens were stored in distilled water at 37°C for 24 hours and then subjected to 5000, 10,000, 30,000, or 50,000 TC between 5°C and 55°C before shear bond strength (SBS) testing, creating a division into a total of five different storage conditions. Baseline specimens were stored in distilled water at 37°C for 24 hours. The SBS test was performed at a cross-head speed of 1.0 mm/min. Three-way analysis of variance revealed that all the factors of application mode, adhesive, and thermal cycle period significantly influenced the SBS values ( p<0.001), regardless of the etching mode. In the baseline groups, all of the tested adhesives with active application had higher SBS values than those with inactive application, regardless of etching mode. In the TC groups, significantly lower SBS values were observed at 50,000 TC with inactive application compared to those with active application, regardless of the etching mode. From the scanning electron microscopy observation of demineralized and deproteinized resin/dentin interfaces, dense resin tags longer than 50 µm were observed in the etch-and-rinse with active application group. On the other hand, the resin tags in self-etch mode were sparse, thin, and much shorter than those in etch-and-rinse mode. Comparing the penetration status of the resin tags with active and inactive application in self-etch mode, the resin tag penetration with inactive application was much lower than that with active application. Active application is effective in enhancing the dentin bond durability of universal adhesives. When using universal adhesives with different etching modes, practitioners should select the optimal etching mode and appropriate application method in accordance with the cavity conditions.


Assuntos
Colagem Dentária , Adesivos Dentinários , Condicionamento Ácido do Dente , Animais , Bovinos , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina
12.
Nat Mater ; 16(11): 1090-1095, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28967918

RESUMO

Weyl fermions have been observed as three-dimensional, gapless topological excitations in weakly correlated, inversion-symmetry-breaking semimetals. However, their realization in spontaneously time-reversal-symmetry-breaking phases of strongly correlated materials has so far remained hypothetical. Here, we report experimental evidence for magnetic Weyl fermions in Mn3Sn, a non-collinear antiferromagnet that exhibits a large anomalous Hall effect, even at room temperature. Detailed comparison between angle-resolved photoemission spectroscopy (ARPES) measurements and density functional theory (DFT) calculations reveals significant bandwidth renormalization and damping effects due to the strong correlation among Mn 3d electrons. Magnetotransport measurements provide strong evidence for the chiral anomaly of Weyl fermions-namely, the emergence of positive magnetoconductance only in the presence of parallel electric and magnetic fields. Since weak magnetic fields (approximately 10 mT) are adequate to control the distribution of Weyl points and the large fictitious fields (equivalent to approximately a few hundred T) produced by them in momentum space, our discovery lays the foundation for a new field of science and technology involving the magnetic Weyl excitations of strongly correlated electron systems such as Mn3Sn.

13.
Rev Sci Instrum ; 88(4): 043301, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28456255

RESUMO

Water vapor transmission rate (WVTR) measuring devices with a quadrupole mass spectrometer (QMS) have an advantage in measuring low WVTRs because measurements are taken under an extremely low background of water vapor by realizing ultrahigh vacuum conditions. Here, the reliability of the QMS measurements was improved by including a porous plug with known molecular conductance in the device to generate a reference molar flux for in situ QMS calibration. Then, standard gas barrier (SGB) films made from a clay-polyimide nanocomposite film were also developed and used to validate the measurement. The measurement results for the SGB films were on the extrapolated calibration curve obtained with the porous plug down to WVTR at the 10-6 g m-2 day-1 level within the estimated measurement uncertainty.

14.
Am J Transplant ; 16(2): 426-39, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26495767

RESUMO

Recently, the immune-regulating potential of invariant natural killer T (iNKT) cells has attracted considerable attention. We previously reported that a combination treatment with a liposomal ligand for iNKT cells and an anti-CD154 antibody in a sublethally irradiated murine bone marrow transplant (BMT) model resulted in the establishment of mixed hematopoietic chimerism through in vivo expansion of regulatory T cells (Tregs). Herein, we show the lack of alloreactivity of CD8(+) T cells in chimeras and an early expansion of donor-derived dendritic cells (DCs) in the recipient thymi accompanied by a sequential reduction in the donor-reactive Vß-T cell receptor repertoire, suggesting a contribution of clonal deletion in this model. Since thymic expansion of donor DCs and the reduction in the donor-reactive T cell repertoire were precluded with Treg depletion, we presumed that Tregs should preform before the establishment of clonal deletion. In contrast, the mice thymectomized before BMT failed to increase the number of Tregs and to establish CD8(+) T cell tolerance, suggesting the presence of mutual dependence between the thymic donor-DCs and Tregs. These results provide new insights into the regulatory mechanisms that actively promote clonal deletion.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Deleção Clonal/imunologia , Tolerância Imunológica/imunologia , Células T Matadoras Naturais/imunologia , Transplante de Pele , Linfócitos T Reguladores/imunologia , Timo/imunologia , Animais , Transplante de Medula Óssea , Quimerismo , Citometria de Fluxo , Sobrevivência de Enxerto , Camundongos , Camundongos Endogâmicos AKR , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Doadores de Tecidos
16.
Eye (Lond) ; 26(10): 1363-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22878452

RESUMO

PURPOSE: To assess the additive effect of diquafosol tetrasodium on sodium hyaluronate monotherapy in patients with dry eye syndrome. METHODS: This study evaluated 64 eyes of 32 patients (age: 62.6±12.8 years (mean±SD)) in whom treatment with 0.1% sodium hyaluronate was insufficiently responsive. The eyes were randomly assigned to one of the two regimens in each patient: topical administration of sodium hyaluronate and diquafosol tetrasodium in one eye, and that of sodium hyaluronate in the other. Before treatment, and 2 and 4 weeks after treatment, we determined tear volume, tear film break-up time (BUT), fluorescein and rose bengal vital staining scores, subjective symptoms, and adverse events. RESULTS: We found a significant improvement in BUT (P=0.049, Dunnett test), fluorescein and rose bengal staining scores (P=0.02), and in subjective symptoms (P=0.004 for dry eye sensation, P=0.02 for pain, and P=0.02 for foreign body sensation) 4 weeks after treatment in the diquafosol eyes. On the other hand, we found no significant change in these parameters after treatment in the control eyes. CONCLUSIONS: In dry eyes, where sodium hyaluronate monotherapy was insufficient, diquafosol tetrasodium was effective in improving objective and subjective symptoms, suggesting its viability as an option for the additive treatment of such eyes.


Assuntos
Síndromes do Olho Seco/tratamento farmacológico , Ácido Hialurônico/administração & dosagem , Polifosfatos/administração & dosagem , Agonistas do Receptor Purinérgico P2Y/administração & dosagem , Nucleotídeos de Uracila/administração & dosagem , Viscossuplementos/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Combinada , Síndromes do Olho Seco/metabolismo , Síndromes do Olho Seco/fisiopatologia , Feminino , Fluoresceína/metabolismo , Corantes Fluorescentes/metabolismo , Humanos , Ácido Hialurônico/efeitos adversos , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Polifosfatos/efeitos adversos , Estudos Prospectivos , Agonistas do Receptor Purinérgico P2Y/efeitos adversos , Rosa Bengala/metabolismo , Lágrimas/química , Nucleotídeos de Uracila/efeitos adversos , Viscossuplementos/efeitos adversos
17.
Br J Radiol ; 85(1020): 1533-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22844034

RESUMO

OBJECTIVE: The aim of this study was to assess clinical and pulmonary thin-section CT findings in patients with acute Pseudomonas aeruginosa (PA) pulmonary infection. METHODS: We retrospectively identified 44 patients with acute PA pneumonia who had undergone chest thin-section CT examinations between January 2004 and December 2010. We excluded nine patients with concurrent infections. The final study group comprised 35 patients (21 males, 14 females; age range 30-89 years, mean age 66.9 years) with PA pneumonia. The patients' clinical findings were assessed. Parenchymal abnormalities, enlarged lymph nodes and pleural effusion were evaluated on thin-section CT. RESULTS: Underlying diseases included malignancy (n=13), a smoking habit (n=11) and cardiac disease (n=8). CT scans of all patients revealed abnormal findings, including ground-glass opacity (n=34), bronchial wall thickening (n=31), consolidation (n=23) and cavities (n=5). Pleural effusion was found in 15 patients. CONCLUSION: PA pulmonary infection was observed in patients with underlying diseases such as malignancy or a smoking habit. The CT findings in patients with PA consisted mainly of ground-glass attenuation and bronchial wall thickening. ADVANCES IN KNOWLEDGE: The CT findings consisted mainly of ground-glass attenuation, bronchial wall thickening and cavities. These findings in patients with an underlying disease such as malignancy or a smoking habit may be suggestive of pneumonia caused by PA infection.


Assuntos
Pneumonia Bacteriana/diagnóstico por imagem , Infecções por Pseudomonas/diagnóstico por imagem , Pseudomonas aeruginosa , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Comunitárias Adquiridas/diagnóstico por imagem , Infecção Hospitalar/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
18.
Science ; 336(6081): 559-63, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22556246

RESUMO

Frustrated magnetic materials, in which local conditions for energy minimization are incompatible because of the lattice structure, can remain disordered to the lowest temperatures. Such is the case for Ba(3)CuSb(2)O(9), which is magnetically anisotropic at the atomic scale but curiously isotropic on mesoscopic length and time scales. We find that the frustration of Wannier's Ising model on the triangular lattice is imprinted in a nanostructured honeycomb lattice of Cu(2+) ions that resists a coherent static Jahn-Teller distortion. The resulting two-dimensional random-bond spin-1/2 system on the honeycomb lattice has a broad spectrum of spin-dimer-like excitations and low-energy spin degrees of freedom that retain overall hexagonal symmetry.

19.
Br J Radiol ; 85(1016): e357-64, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22215884

RESUMO

OBJECTIVES: The aim of this study was to compare the pulmonary thin-section CT findings of patients with acute Streptococcus pneumoniae pneumonia with and without concurrent infection. METHODS: The study group comprised 86 patients with acute S. pneumoniae pneumonia, 36 patients with S. pneumoniae pneumonia combined with Haemophilus influenzae infection, 26 patients with S. pneumoniae pneumonia combined with Pseudomonas aeruginosa infection and 22 patients with S. pneumoniae pneumonia combined with methicillin-susceptible Staphylococcus aureus (MSSA) infection. We compared the thin-section CT findings among the groups. RESULTS: Centrilobular nodules and bronchial wall thickening were significantly more frequent in patients with pneumonia caused by concurrent infection (H. influenzae: p<0.001 and p<0.001, P. aeruginosa: p<0.001 and p<0.001, MSSA: p<0.001 and p<0.001, respectively) than in those infected with S. pneumoniae alone. Cavity and bilateral pleural effusions were significantly more frequent in cases of S. pneumoniae pneumonia with concurrent P. aeruginosa infection than in cases of S. pneumoniae pneumonia alone (p<0.001 and p<0.001, respectively) or with concurrent H. influenzae (p<0.05 and p<0.001, respectively) or MSSA infection (p<0.05 and p<0.05, respectively). CONCLUSIONS: When a patient with S. pneumoniae pneumonia has centrilobular nodules, bronchial wall thickening, cavity or bilateral pleural effusions on CT images, concurrent infection should be considered.


Assuntos
Pneumonia Pneumocócica/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Broncopatias/diagnóstico por imagem , Broncopatias/microbiologia , Feminino , Seguimentos , Infecções por Haemophilus/complicações , Infecções por Haemophilus/diagnóstico por imagem , Haemophilus influenzae , Humanos , Doenças Linfáticas/diagnóstico por imagem , Doenças Linfáticas/microbiologia , Masculino , Pessoa de Meia-Idade , Derrame Pleural/diagnóstico por imagem , Derrame Pleural/microbiologia , Pneumonia Pneumocócica/complicações , Prognóstico , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/diagnóstico por imagem , Pseudomonas aeruginosa , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/diagnóstico por imagem , Staphylococcus aureus , Tomografia Computadorizada por Raios X , Adulto Jovem
20.
Br J Radiol ; 85(1010): 121-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21224303

RESUMO

OBJECTIVE: The aim of this study was to assess pulmonary thin-section CT findings in patients with acute Haemophilus influenzae pulmonary infection. METHODS: Thin-section CT scans obtained between January 2004 and March 2009 from 434 patients with acute H. influenzae pulmonary infection were retrospectively evaluated. Patients with concurrent infection diseases, including Streptococcus pneumoniae (n=76), Staphylococcus aureus (n=58) or multiple pathogens (n=89) were excluded from this study. Thus, our study group comprised 211 patients (106 men, 105 women; age range, 16-91 years, mean, 63.9 years). Underlying diseases included cardiac disease (n=35), pulmonary emphysema (n=23), post-operative status for malignancy (n=20) and bronchial asthma (n=15). Frequencies of CT patterns and disease distribution of parenchymal abnormalities, lymph node enlargement and pleural effusion were assessed by thin-section CT. RESULTS: The CT findings in patients with H. influenzae pulmonary infection consisted mainly of ground-glass opacity (n=185), bronchial wall thickening (n=181), centrilobular nodules (n=137) and consolidation (n=112). These abnormalities were predominantly seen in the peripheral lung parenchyma (n=108). Pleural effusion was found in 22 patients. Two patients had mediastinal lymph node enlargement. CONCLUSION: These findings in elderly patients with smoking habits or cardiac disease may be characteristic CT findings of H. influenzae pulmonary infection.


Assuntos
Infecções por Haemophilus/diagnóstico por imagem , Haemophilus influenzae , Pneumopatias/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Infecções por Haemophilus/complicações , Cardiopatias/complicações , Cardiopatias/diagnóstico por imagem , Humanos , Pulmão/diagnóstico por imagem , Pneumopatias/complicações , Masculino , Pessoa de Meia-Idade , Enfisema Pulmonar/complicações , Enfisema Pulmonar/diagnóstico por imagem , Estudos Retrospectivos , Fatores de Risco , Fumar , Adulto Jovem
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