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1.
Br Poult Sci ; 64(1): 47-55, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36129068

RESUMEN

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.


Asunto(s)
Pollos , Óvulo , Femenino , Animales , Yema de Huevo , Dieta/veterinaria , Carotenoides , Suplementos Dietéticos/análisis , Alimentación Animal/análisis , Huevos/análisis
2.
Epidemiol Infect ; 149: e244, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34726137

RESUMEN

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.


Asunto(s)
Brotes de Enfermedades , Escherichia coli/aislamiento & purificación , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/microbiología , Toxinas Bacterianas/genética , Toxinas Bacterianas/aislamiento & purificación , ADN Bacteriano/genética , Farmacorresistencia Bacteriana , Enterotoxinas/genética , Enterotoxinas/aislamiento & purificación , Escherichia coli/genética , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/aislamiento & purificación , Contaminación de Alimentos , Servicios de Alimentación , Enfermedades Transmitidas por los Alimentos/etiología , Humanos , Japón/epidemiología , Rhodophyta , Secuenciación Completa del Genoma
3.
BJOG ; 128(2): 329-335, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32298518

RESUMEN

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.


Asunto(s)
Brazo/embriología , Diabetes Gestacional/diagnóstico por imagen , Desarrollo Fetal/fisiología , Feto/diagnóstico por imagen , Muslo/embriología , Adulto , Brazo/diagnóstico por imagen , Diáfisis/diagnóstico por imagen , Diáfisis/embriología , Femenino , Fémur/diagnóstico por imagen , Fémur/embriología , Edad Gestacional , Humanos , Húmero/diagnóstico por imagen , Húmero/embriología , Japón , Tamaño de los Órganos , Embarazo , Muslo/diagnóstico por imagen , Ultrasonografía Prenatal
4.
Pharmazie ; 76(12): 611-613, 2021 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-34986958

RESUMEN

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.


Asunto(s)
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 del Citocromo P-450/metabolismo , Dopamina/metabolismo , Humanos , Hidrocortisona , Hidroxilación , Microsomas Hepáticos/metabolismo , Progesterona/metabolismo , Esteroides , Testosterona/metabolismo , Tolbutamida/metabolismo
5.
Opt Express ; 28(15): 22524-22539, 2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32752512

RESUMEN

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.

6.
Ultrasound Obstet Gynecol ; 55(2): 226-232, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31008542

RESUMEN

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.


Asunto(s)
Reglas de Decisión Clínica , Anomalía de Ebstein/diagnóstico , Ecocardiografía/métodos , Cardiopatías Congénitas/diagnóstico , Diagnóstico Prenatal/métodos , Insuficiencia de la Válvula Tricúspide/diagnóstico , Anomalía de Ebstein/embriología , Anomalía de Ebstein/mortalidad , Femenino , Edad Gestacional , Cardiopatías Congénitas/embriología , Cardiopatías Congénitas/mortalidad , Humanos , Recién Nacido , Muerte Perinatal/etiología , Mortalidad Perinatal , Valor Predictivo de las Pruebas , Embarazo , Pronóstico , Estudios Retrospectivos , Válvula Tricúspide/embriología , Insuficiencia de la Válvula Tricúspide/embriología , Insuficiencia de la Válvula Tricúspide/mortalidad , Función Ventricular Izquierda
7.
Nat Mater ; 16(11): 1090-1095, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28967918

RESUMEN

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.

8.
Am J Transplant ; 16(2): 426-39, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26495767

RESUMEN

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.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Supresión Clonal/inmunología , Tolerancia Inmunológica/inmunología , Células T Asesinas Naturales/inmunología , Trasplante de Piel , Linfocitos T Reguladores/inmunología , Timo/inmunología , Animales , Trasplante de Médula Ósea , Quimerismo , Citometría de Flujo , Supervivencia de Injerto , Ratones , Ratones Endogámicos AKR , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Donantes de Tejidos
9.
Oper Dent ; 46(3): 306-315, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34411249

RESUMEN

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.


Asunto(s)
Resinas Compuestas , Caries Dental , Color , Humanos , Ensayo de Materiales , Espectrofotometría , Agua
10.
Oper Dent ; 46(3): E117-E131, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34370032

RESUMEN

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.


Asunto(s)
Pulido Dental , Resistencia Flexional , Óxido de Aluminio , Resinas Compuestas , Ensayo de Materiales , Propiedades de Superficie
11.
Oper Dent ; 45(2): 183-195, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31567054

RESUMEN

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.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Grabado Ácido Dental , Adhesivos , Animales , Bovinos , Cementos Dentales , Dentina , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte
12.
Oper Dent ; 45(2): E91-E104, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31738697

RESUMEN

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.


Asunto(s)
Pulido Dental , Restauración Dental Permanente , Óxido de Aluminio , Resinas Compuestas , Diamante , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie
13.
Oper Dent ; 44(2): 188-199, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30106329

RESUMEN

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.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios , Grabado Ácido Dental , Animales , Bovinos , Cementos Dentales , Dentina , Ensayo de Materiales , Cementos de Resina
15.
Ecology ; 89(2): 567-80, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18409445

RESUMEN

Scaling relationships between mean body masses and abundances of species in multitrophic communities continue to be a subject of intense research and debate. The top-down mechanism explored in this paper explains the frequently observed inverse linear relationship between body mass and abundance (i.e., constant biomass) in terms of a balancing of resource biomasses by behaviorally and evolutionarily adapting foragers, and the evolutionary response of resources to this foraging pressure. The mechanism is tested using an allometric, multitrophic community model with a complex food web structure. It is a statistical model describing the evolutionary and population dynamics of tens to hundreds of species in a uniform way. Particularities of the model are the detailed representation of the evolution and interaction of trophic traits to reproduce topological food web patterns, prey switching behavior modeled after experimental observations, and the evolutionary adaptation of attack rates. Model structure and design are discussed. For model states comparable to natural communities, we find that (1) the body-mass abundance scaling does not depend on the allometric scaling exponent of physiological rates in the form expected from the energetic equivalence rule or other bottom-up theories; (2) the scaling exponent of abundance as a function of body mass is approximately -1, independent of the allometric exponent for physiological rates assumed; (3) removal of top-down control destroys this pattern, and energetic equivalence is recovered. We conclude that the top-down mechanism is active in the model, and that it is a viable alternative to bottom-up mechanisms for controlling body-mass-abundance relations in natural communities.


Asunto(s)
Biomasa , Ecosistema , Conducta Alimentaria/fisiología , Cadena Alimentaria , Modelos Biológicos , Animales , Biodiversidad , Tamaño Corporal , Preferencias Alimentarias , Densidad de Población , Dinámica Poblacional , Especificidad de la Especie
16.
Rev Sci Instrum ; 88(4): 043301, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28456255

RESUMEN

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.

17.
Nucleic Acids Res ; 32(Database issue): D560-7, 2004 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-14681481

RESUMEN

GermOnline provides information and microarray expression data for genes involved in mitosis and meiosis, gamete formation and germ line development across species. The database has been developed, and is being curated and updated, by life scientists in cooperation with bioinformaticists. Information is contributed through an online form using free text, images and the controlled vocabulary developed by the GeneOntology Consortium. Authors provide up to three references in support of their contribution. The database is governed by an international board of scientists to ensure a standardized data format and the highest quality of GermOnline's information content. Release 2.0 provides exclusive access to microarray expression data from Saccharomyces cerevisiae and Rattus norvegicus, as well as curated information on approximately 700 genes from various organisms. The locus report pages include links to external databases that contain relevant annotation, microarray expression and proteome data. Conversely, the Saccharomyces Genome Database (SGD), S.cerevisiae GeneDB and Swiss-Prot link to the budding yeast section of GermOnline from their respective locus pages. GermOnline, a fully operational prototype subject-oriented knowledgebase designed for community annotation and array data visualization, is accessible at http://www.germonline.org. The target audience includes researchers who work on mitotic cell division, meiosis, gametogenesis, germ line development, human reproductive health and comparative genomics.


Asunto(s)
Diferenciación Celular/genética , Bases de Datos Genéticas , Perfilación de la Expresión Génica , Células Germinativas/citología , Células Germinativas/metabolismo , Animales , Biología Computacional , Genómica , Humanos , Almacenamiento y Recuperación de la Información , Internet , Meiosis/genética , Mitosis/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas/metabolismo , Proteoma , Proteómica , Ratas
18.
Cancer Res ; 60(22): 6311-3, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11103790

RESUMEN

Peutz-Jeghers syndrome (PJS) is characterized by multiple gastrointestinal hamartomatous polyps, mucocutaneous melanin deposition, and increased risk of cancer, mainly in the gastrointestinal tract. We examined mutations of the LKB1, beta-catenin, APC, K-ras, and p53 genes in 27 gastrointestinal hamartomatous polyps from 10 patients in nine PJS families. Of these hamartomatous polyps, one intestinal polyp had an adenomatous lesion, and one gastric polyp contained adenomatous and carcinomatous lesions. Germ-line mutations of the LKB1 gene were detected in six PJS families. Somatic mutations of the LKB1 gene were found in 5 polyps, whereas loss of heterozygosity (LOH) at the LKB1 locus at 19p was seen in 14 other polyps. In adenomatous lesions microdissected from hamartomatous polyps, both beta-catenin mutation and 19p LOH were detected. Furthermore, a carcinomatous lesion in a gastric hamartomatous polyp was found to contain a mutation of the p53 gene and LOH at the p53 locus in addition to LOH at the LKB1 locus and a beta-catenin mutation. K-ras mutations were detected in a few polyps, whereas no APC mutation or 5q LOH was detected in hamartomatous polyps. These results suggest that gastrointestinal hamartomatous polyps in PJS patients develop through inactivation of the LKB1 gene by germ-line mutation plus somatic mutation or LOH of the unaffected LKB1 allele, and that additional mutations of the beta-catenin gene and p53 gene convert hamartomatous polyps into adenomatous and carcinomatous lesions.


Asunto(s)
Proteínas del Citoesqueleto/genética , Mutación , Síndrome de Peutz-Jeghers/genética , Proteínas Serina-Treonina Quinasas/genética , Transactivadores , Quinasas de la Proteína-Quinasa Activada por el AMP , Adenoma/genética , Adenoma/patología , Carcinoma/genética , Carcinoma/patología , Neoplasias Gastrointestinales/genética , Neoplasias Gastrointestinales/patología , Mutación de Línea Germinal , Hamartoma/genética , Hamartoma/patología , Humanos , Pérdida de Heterocigocidad , Síndrome de Peutz-Jeghers/complicaciones , Síndrome de Peutz-Jeghers/patología , beta Catenina
19.
Biochim Biophys Acta ; 1568(1): 74-82, 2001 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-11731088

RESUMEN

An aqueous acetone extract of the pericarps of Mallotus japonicus (MJE) inhibited nitric oxide (NO) production by a murine macrophage-like cell line, RAW 264.7, which was activated by lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma). Seven phloroglucinol derivatives isolated from MJE exhibited inhibitory activity against NO production. Among these phloroglucinol derivatives, isomallotochromanol exhibited strong inhibitory activity toward NO production, exhibiting an IC(50) of 10.7 microM. MJE and the phloroglucinol derivatives significantly reduced both the induction of inducible nitric oxide synthase (iNOS) protein and iNOS mRNA expression. NO production by macrophages preactivated with LPS and IFN-gamma for 16 h was also inhibited by MJE and the phloroglucinol derivatives. Furthermore, MJE and the derivatives directly affected the conversion of L-[(14)C]arginine to L-[(14)C]citrulline by the cell extract. These results suggest that MJE and the phloroglucinol derivatives have the pharmacological ability to suppress NO production by activated macrophages. They inhibited NO production by two mechanisms: reduction of iNOS protein induction and inhibition of enzyme activity.


Asunto(s)
Euphorbiaceae , Macrófagos/efectos de los fármacos , Óxido Nítrico/biosíntesis , Floroglucinol/análogos & derivados , Animales , Línea Celular , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Interferón gamma , Lipopolisacáridos , Activación de Macrófagos , Macrófagos/metabolismo , Ratones , Estructura Molecular , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Floroglucinol/farmacología , Extractos Vegetales/farmacología , ARN Mensajero/biosíntesis
20.
J Bone Joint Surg Br ; 87(6): 804-8, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15911663

RESUMEN

We performed a randomised, prospective study of 80 mobile-bearing total knee arthroplasties (80 knees) in order to measure the effects of varus-valgus laxity and balance on the range of movement (ROM) one year after operation. Forty knees had a posterior-cruciate-ligament (PCL)-retaining prosthesis and the other 40 a PCL-sacrificing prosthesis. In the balanced group (69 knees) in which the difference between varus and valgus was less than 2 degrees, the mean ROM improved significantly from 107.6 degrees to 117.7 degrees (p < 0.0001). By contrast, in the 11 knees which were unbalanced and in which the difference between varus and valgus laxity exceeded 2 degrees, the ROM decreased from a mean of 121.0 degrees to 112.7 degrees (p = 0.0061). We conclude that coronal laxity, especially balanced laxity, is important for achieving an improved ROM in mobile-bearing total knee arthroplasty.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Articulación de la Rodilla/fisiopatología , Rango del Movimiento Articular , Anciano , Fenómenos Biomecánicos , Femenino , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/fisiopatología , Prótesis de la Rodilla , Masculino , Ligamento Cruzado Posterior/cirugía , Estudios Prospectivos , Radiografía
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