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1.
J Helminthol ; 92(4): 395-402, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28784187

RESUMEN

Clonorchis sinensis and Capillaria hepatica are zoonotic parasites that mainly infect the liver and cause serious liver disorders. However, immunological parameters induced by co-infection with these parasites remain unknown. In this study, for the first time, we investigated immunological profiles induced by co-infection with C. hepatica (CH) in C. sinensis (CS)-infected rats (Sprague-Dawley). Rats were infected primarily with 50 metacercariae of C. sinensis; 4 weeks later, they were subsequently infected with 1000 infective C. hepatica eggs. Significantly higher levels of C. sinensis- or C. hepatica-specific IgG antibodies were found in the sera of rats. Interestingly, no cross-reacting antibody was observed between C. sinensis and C. hepatica infections. Significantly raised eosinophil levels were found in the blood of C. sinensis/C. hepatica co-infected rats (CS + CH) compared to the blood of rats infected singly with C. sinensis. Co-infected rats showed significantly higher levels of lymphocyte proliferation and cytokine production compared to a single C. sinensis infection. The worm burden of C. sinensis was significantly reduced in co-infected rats compared to the single C. sinensis infection. These results indicate that the eosinophils, lymphocyte proliferation and cytokine production induced by subsequent infection with C. hepatica in C. sinensis-infected rats might contribute to the observed C. sinensis worm reduction.


Asunto(s)
Anticuerpos Antihelmínticos/inmunología , Capillaria/fisiología , Clonorquiasis/inmunología , Clonorchis sinensis/fisiología , Coinfección/inmunología , Infecciones por Enoplida/inmunología , Animales , Anticuerpos Antihelmínticos/sangre , Capillaria/inmunología , Clonorquiasis/sangre , Clonorquiasis/parasitología , Clonorchis sinensis/inmunología , Coinfección/sangre , Coinfección/parasitología , Citocinas/inmunología , Modelos Animales de Enfermedad , Infecciones por Enoplida/sangre , Infecciones por Enoplida/parasitología , Humanos , Masculino , Metacercarias/inmunología , Metacercarias/fisiología , Conejos , Ratas , Ratas Sprague-Dawley
2.
Phys Rev Lett ; 119(19): 197204, 2017 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-29219521

RESUMEN

Modulation and δ-doping strategies, in which atomically thin layers of charged dopants are precisely deposited within a heterostructure, have played enabling roles in the discovery of new physical behavior in electronic materials. Here, we demonstrate a purely structural "δ-doping" strategy in complex oxide heterostructures, in which atomically thin manganite layers are inserted into an isovalent manganite host, thereby modifying the local rotations of corner-connected MnO_{6} octahedra. Combining scanning transmission electron microscopy, polarized neutron reflectometry, and density functional theory, we reveal how local magnetic exchange interactions are enhanced within the spatially confined regions of suppressed octahedral rotations. The combined experimental and theoretical results illustrate the potential to utilize noncharge-based approaches to "doping" in order to enhance or suppress functional properties within spatially confined regions of oxide heterostructures.

3.
Nano Lett ; 14(5): 2509-14, 2014 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-24697503

RESUMEN

We investigate structural coupling of the MnO6 octahedra across a film/substrate interface and the resultant changes of the physical properties of ultrathin La2/3Sr1/3MnO3 (LSMO) films. In order to isolate the effect of interfacial MnO6 octahedral behavior from that of epitaxial strain, LSMO films are grown on substrates with different symmetry and similar lattice parameters. Ultrathin LSMO films show an increased magnetization and electrical conductivity on cubic (LaAlO3)0.3(Sr2AlTaO6)0.7 (LSAT) compared to those grown on orthorhombic NdGaO3 (NGO) substrates, an effect that subsides as the thickness of the films is increased. This study demonstrates that interfacial structural coupling can play a critical role in the functional properties of oxide heterostructures.

4.
Oral Dis ; 20(8): 773-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24735459

RESUMEN

OBJECTIVE: This study assessed trends in the incidence of and survival rates for oral cavity cancer in the Korean population. MATERIALS AND METHODS: Data from the Korea Central Cancer Registry were extracted for 10,282 patients diagnosed with oral cavity cancer (C01-C06) between 1999 and 2010 to evaluate the age-standardised incidence rate, annual percentage change (APC) and 5-year relative survival rate (RSR) according to gender and age. RESULTS: In males, the incidence rate slightly decreased [APC of -0.2% (P = 0.6427)]; in females, the incidence rate increased [APC of 3.1% (P < 0.05)]. In males and females, the incidence of oral tongue cancer (C02) significantly increased [APC of 2.2% and 4.1%, respectively (P < 0.05)]. This increase in oral tongue cancer incidence was most prominent in the younger age group (<40 years, APC = 6.1%, P < 0.05). The incidence of buccal cheek cancer increased only among males [APC of 4.8% (P < 0.05)]. The 5-year RSR improved from 42.7% (1993-1995) to 59.5% (2006-2010), corresponding to an increase of 16.8% from 1993 to 2010 (P < 0.05). CONCLUSION: The incidence of oral cavity cancer in females increased, whereas it stabilised or decreased in males. However, the incidence of oral tongue cancer increased in both males and females, especially in the younger age group.


Asunto(s)
Neoplasias de la Boca/mortalidad , Adulto , Anciano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/fisiopatología , República de Corea/epidemiología , Tasa de Supervivencia
5.
Asian-Australas J Anim Sci ; 27(12): 1749-54, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25358369

RESUMEN

The current experiment was designed to evaluate the efficacy of adding the multi-enzyme mixture (Natuzyme) into layers' diets with different levels of energy and available phosphorus in relation to laying performance, egg qualities, blood cholesterol level, microflora and intestinal viscosity. Two hundred and fifty 43-wk-old Hy-Line commercial layers were divided into five groups with five replicates per group (10 birds per replicate) and fed one of five experimental diets. A corn and soybean meal-based control diet was formulated and used as a control diet. Two experimental control diets were formulated to reduce energy and crude protein contents (rE) or energy, crude protein and phosphorus contents (rEP). In addition, Natuzyme was added into either rE (rE-Natu500) or rEP (rEP-Natu500) diet to reach a concentration of 500 mg per kg of diet. The experiment lasted 8 weeks. There were no significant differences in feed intake, egg production, egg weight, egg qualities such as eggshell color or Haugh unit, total cholesterol, relative organ weights and cecal microflora profiles between any dietary treatments. Natu500 supplementation into the rE diet, but not rEP diet significantly increased egg mass and eggshell qualities such as strength and thickness, but it decreased cecal ammonia concentration and intestinal viscosity in laying hens. In conclusion, the present study shows that adding multiple enzyme preparation could improve performance of laying hens fed energy and protein restricted diets.

6.
Sci Rep ; 12(1): 3219, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35256630

RESUMEN

Combinatorial synthesis via a continuous composition spread is an excellent route to develop thin-film libraries as it is both time- and cost-efficient. Creating libraries of functional, multicomponent, complex oxide films requires excellent control over the synthesis parameters combined with high-throughput analytical feedback. A reliable, high-throughput, in-situ characterization analysis method is required to meet the crucial need to rapidly screen materials libraries. Here, we report on the combination of two in-situ techniques-(a) Reflection high-energy electron diffraction (RHEED) for heteroepitaxial characterization and a newly developed compositional analysis technique, low-angle x-ray spectroscopy (LAXS), to map the chemical composition profile of combinatorial heteroepitaxial complex oxide films deposited using a continuous composition spread method via pulsed laser deposition. This is accomplished using a unique state-of-the-art combinatorial growth system with a fully synchronized four-axis mechanical substrate stage without shadow masks, alternating acquisition of chemical compositional data using LAXS at various different positions on the [Formula: see text] 41 mm [Formula: see text] 41 mm range and sequential deposition of multilayers of SrTiO[Formula: see text] and [Formula: see text] on a 2-inch (50.8 mm) [Formula: see text] wafer in a single growth run. Rutherford backscattering spectrometry (RBS) is used to calibrate and validate the compositions determined by LAXS. This study shows the feasibility of combinatorial synthesis of heteroepitaxial, functional complex oxide films at wafer-scale via two essential in-situ characterization tools-RHEED for structural analysis or heteroepitaxy and LAXS for compositional characterization. This is a powerful technique for development of new films with optimized heteroepitaxy and composition.

7.
Phys Rev Lett ; 107(11): 116805, 2011 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-22026694

RESUMEN

Using resonant x-ray spectroscopies combined with density functional calculations, we find an asymmetric biaxial strain-induced d-orbital response in ultrathin films of the correlated metal LaNiO3 which are not accessible in the bulk. The sign of the misfit strain governs the stability of an octahedral "breathing" distortion, which, in turn, produces an emergent charge-ordered ground state with an altered ligand-hole density and bond covalency. Control of this new mechanism opens a pathway to rational orbital engineering, providing a platform for artificially designed Mott materials.

8.
Nat Med ; 7(4): 437-43, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11283670

RESUMEN

Low oxygen tension influences tumor progression by enhancing angiogenesis; and histone deacetylases (HDAC) are implicated in alteration of chromatin assembly and tumorigenesis. Here we show induction of HDAC under hypoxia and elucidate a role for HDAC in the regulation of hypoxia-induced angiogenesis. Overexpressed wild-type HDAC1 downregulated expression of p53 and von Hippel-Lindau tumor suppressor genes and stimulated angiogenesis of human endothelial cells. A specific HDAC inhibitor, trichostatin A (TSA), upregulated p53 and von Hippel-Lindau expression and downregulated hypoxia-inducible factor-1alpha and vascular endothelial growth factor. TSA also blocked angiogenesis in vitro and in vivo. TSA specifically inhibited hypoxia-induced angiogenesis in the Lewis lung carcinoma model. These results indicate that hypoxia enhances HDAC function and that HDAC is closely involved in angiogenesis through suppression of hypoxia-responsive tumor suppressor genes.


Asunto(s)
Genes Supresores de Tumor , Histona Desacetilasas/fisiología , Neovascularización Fisiológica/genética , Factores de Transcripción , Animales , Bovinos , Línea Celular , Proteínas de Unión al ADN/genética , Factores de Crecimiento Endotelial/genética , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Genes Supresores de Tumor/efectos de los fármacos , Genes p53/efectos de los fármacos , Inhibidores de Histona Desacetilasas , Humanos , Ácidos Hidroxámicos/farmacología , Hipoxia/genética , Hipoxia/patología , Factor 1 Inducible por Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia , Linfocinas/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica/efectos de los fármacos , Proteínas Nucleares/genética , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular , Enfermedad de von Hippel-Lindau/genética
9.
Cell Mol Biol (Noisy-le-grand) ; 56 Suppl: OL1215-22, 2010 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-20158974

RESUMEN

Asarone is a molecule found in certain plants such as Acorus calamus, the root of which is used in traditional medicine to treat diabetes. We determined the molecular mechanism underlying the anti-diabetic activity of asarone. Treatment of asarone significantly inhibited the differentiation of 3T3-L1 preadipocytes through suppression of expression of the transcription factors, CCAAT/enhancer binding protein-alpha and peroxisome proliferator activated receptor-gamma, which activate adipogenesis. Intracellular triglyceride levels were reduced by asarone in a dose-dependent manner and asarone treatment stimulated the phosphorylation of hormone-sensitive lipase. Together, the present findings indicate that asarone inhibits adipogenesis by down-regulation of PPARgamma and C/EBPalpha and reduces lipid accumulation by stimulation of lipolysis through an increase in hormone-sensitive lipase activity.


Asunto(s)
Adipocitos/metabolismo , Adipogénesis/efectos de los fármacos , Anisoles/farmacología , Hipoglucemiantes/farmacología , Lipólisis/efectos de los fármacos , Células 3T3-L1 , Acorus/química , Derivados de Alilbenceno , Animales , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Ratones , PPAR gamma/metabolismo , Fosforilación , Raíces de Plantas/química , Esterol Esterasa/metabolismo , Factores de Transcripción/metabolismo , Triglicéridos/metabolismo
10.
Lett Appl Microbiol ; 48(1): 33-7, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19018968

RESUMEN

AIMS: Escherichia coli and Bacillus subtilis spores were treated with an atmospheric plasma mixture created by the ionization of helium and oxygen to investigate the inactivation efficiency of a low-temperature plasma below 70 degrees C. METHODS AND RESULTS: An electrical discharge plasma was produced at a radio frequency (RF) of 13.56 MHz, connected to a perforated circular electrode with a discharge spacing of 1-15 mm. The discharge gas was helium with 0-2% oxygen. For the plasma treatment, a dried E. coli cell or B. subtilis endospore suspension on a cover-glass was exposed to oxygen downstream of the plasma from holes in an RF-powered electrode. The sterilization effect of the RF plasma was highest with 0.2% oxygen, corresponding to the maximum production of oxygen radicals. CONCLUSIONS: Oxygen radicals generated by RF plasma are effective for the destruction of bacterial cells and endospores. SIGNIFICANCE AND IMPACT OF THE STUDY: Low-temperature atmospheric plasma can be used for the disinfection of diverse objects, especially for the inactivation of bacterial endospores.


Asunto(s)
Ionización del Aire , Microbiología del Aire , Bacillus subtilis/crecimiento & desarrollo , Escherichia coli/crecimiento & desarrollo , Viabilidad Microbiana , Esterilización/métodos , Antibacterianos/farmacología , Recuento de Colonia Microbiana , Electricidad , Especies Reactivas de Oxígeno/farmacología
11.
Nat Commun ; 10(1): 3282, 2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31337758

RESUMEN

The pseudogap phenomenon in the cuprates is arguably the most mysterious puzzle in the field of high-temperature superconductivity. The tetragonal cuprate HgBa2CuO4+δ, with only one CuO2 layer per primitive cell, is an ideal system to tackle this puzzle. Here, we measure the magnetic susceptibility anisotropy within the CuO2 plane with exceptionally high-precision magnetic torque experiments. Our key finding is that a distinct two-fold in-plane anisotropy sets in below the pseudogap temperature T*, which provides thermodynamic evidence for a nematic phase transition with broken four-fold symmetry. Surprisingly, the nematic director orients along the diagonal direction of the CuO2 square lattice, in sharp contrast to the bond nematicity along the Cu-O-Cu direction. Another remarkable feature is that the enhancement of the diagonal nematicity with decreasing temperature is suppressed around the temperature at which short-range charge-density-wave formation occurs. Our result suggests a competing relationship between diagonal nematic and charge-density-wave order in HgBa2CuO4+δ.

12.
Pain Res Manag ; 13(3): 225-30, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18592059

RESUMEN

Research in the field of pediatric pain has largely ignored the role of fathers in their children's pain experiences. The first objective of the present study was to examine the effect of the presence of mothers versus fathers on children's subjective ratings, facial expressions and physiological responses to acute pain. The second objective was to examine whether child and parent sex influence parents' proxy ratings of their children's pain. The final objective was to compare levels of agreement between mothers' and fathers' assessments of their children's pain. Participants included 73 children (37 boys, 36 girls), four to 12 years of age, along with 32 fathers and 41 mothers. Children undertook the cold pressor pain task while observed by one of their parents. During the task, the children's heart rates and facial expressions were recorded. Children provided self-reports and parents provided proxy reports of child pain intensity using the seven-point Faces Pain Scale. Neither child nor parent sex had a significant impact on children's subjective reports, facial expressions or heart rates in response to acute pain. Fathers gave their sons higher pain ratings than their daughters, whereas mothers' ratings of their sons' and daughters' pain did not differ. Kappa statistics and t tests revealed that fathers tended to be more accurate judges of their children's pain than mothers. Overall, this research highlights the importance of examining both parent and child sex differences in pediatric pain research.


Asunto(s)
Dimensión del Dolor/psicología , Dolor/psicología , Padres/psicología , Adulto , Niño , Preescolar , Frío , Expresión Facial , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Presión , Caracteres Sexuales
13.
Diagn Cytopathol ; 46(10): 815-825, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30195266

RESUMEN

The Papanicolaou Society of Cytopathology has developed a set of guidelines for pulmonary cytology including indications for bronchial brushings, washings, and endobronchial ultrasound guided transbronchial fine-needle aspiration (EBUS-TBNA), technical recommendations for cytological sampling, recommended terminology and classification schemes, recommendations for ancillary testing and recommendations for post-cytological management and follow-up. All recommendations are based on the expertise of the authors, an extensive literature review and feedback from presentations at national and international conferences. This document selectively presents the results of these discussions. The present document summarizes recommendations regarding techniques used to obtain cytological and small histologic specimens from the lung and mediastinal lymph nodes including rapid on-site evaluation (ROSE), and the triage of specimens for immunocytochemical and molecular studies.


Asunto(s)
Citodiagnóstico , Pulmón/patología , Ganglios Linfáticos/patología , Mediastino/patología , Guías de Práctica Clínica como Asunto , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Humanos , Pulmón/diagnóstico por imagen , Ganglios Linfáticos/diagnóstico por imagen , Mediastino/diagnóstico por imagen , Tomografía Computarizada por Rayos X
14.
Nat Commun ; 8(1): 2167, 2017 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-29255140

RESUMEN

A subtle balance between competing interactions in iron-based superconductors (FeSCs) can be tipped by additional interfacial interactions in a heterostructure, often inducing exotic phases with unprecedented properties. Particularly when the proximity-coupled layer is magnetically active, rich phase diagrams are expected in FeSCs, but this has not been explored yet. Here, using high-accuracy 75As and 51V nuclear magnetic resonance measurements, we investigate an electronic phase that emerges in the FeAs layer below T 0 ~ 155 K of Sr2VO3FeAs, a naturally assembled heterostructure of an FeSC and a Mott-insulating vanadium oxide. We find that frustration of the otherwise dominant Fe stripe and V Neel fluctuations via interfacial coupling induces a charge/orbital order in the FeAs layers, without either static magnetism or broken C 4 symmetry, while suppressing the Neel antiferromagnetism in the SrVO3 layers. These findings demonstrate that the magnetic proximity coupling stabilizes a hidden order in FeSCs, which may also apply to other strongly correlated heterostructures.

15.
Opt Express ; 14(21): 9758-63, 2006 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-19529366

RESUMEN

The phase noise of the f-to-2f interferometer used for stabilizing the carrier-envelope phase of a femtosecond laser oscillator was studied by adding a He-Ne laser beam co-propagating with the short pulse laser beam. The noise was reduced to ~60 mrad by stabilizing the optical path length difference of the interferometer. This suppressed the fast jitter of the carrier-envelope phase of the amplified laser pulses from 79 to 48 mrad.

16.
Cancer Res ; 61(8): 3290-3, 2001 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-11309282

RESUMEN

The excessive growth of a tumor requires high rates of glucose uptake and glycolysis and continuous recruitment of new blood vessels. Here, we provide several lines of evidence showing that pyruvic acid, the end product of glycolysis, exhibits strong angiogenic activity. Pyruvic acid promoted angiogenesis in chorioallantoic membrane assay and in vivo mouse Matrigel plug assay. Pyruvic acid also positively affects angiogenic cascade, DNA synthesis, migration, and tube formation in bovine aortic endothelial cells. Furthermore, mRNA expression of fibroblast growth factor receptor-2 and vascular endothelial growth factor was enhanced by pyruvic acid. These results strongly suggest that pyruvic acid plays an important role in angiogenesis for tumor growth and metastasis.


Asunto(s)
Neovascularización Fisiológica/efectos de los fármacos , Ácido Pirúvico/farmacología , Alantoides/irrigación sanguínea , Animales , División Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Embrión de Pollo , Corion/irrigación sanguínea , Colágeno , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Factores de Crecimiento Endotelial/biosíntesis , Factores de Crecimiento Endotelial/genética , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Laminina , Linfocinas/biosíntesis , Linfocinas/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Proteoglicanos , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteínas Tirosina Quinasas Receptoras/biosíntesis , Proteínas Tirosina Quinasas Receptoras/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos/biosíntesis , Receptores de Factores de Crecimiento de Fibroblastos/genética , Estimulación Química , Regulación hacia Arriba/efectos de los fármacos , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
17.
J Hand Surg Eur Vol ; 41(6): 614-20, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26768221

RESUMEN

UNLABELLED: Collagenase clostridium histolyticum has been extensively studied as a treatment modality for Dupuytren's contracture. Its mechanism of action has been documented. It is unknown whether injected collagenase weakens the Dupuytren's cord sufficiently to cause failure during manipulation or if there is digestion and reduction in cord volume. We examined five patients with isolated contractures of the ring or middle metacarpalphalangeal (MP) joint using magnetic resonance imaging (MRI) prior to injection with collagenase and again 1 month following injection. All patients had full correction after manipulation which was maintained at follow-up. The Dupuytren's cord was evaluated with respect to volume, signal intensity, inflammatory changes and continuity. Additionally, signal intensity changes of the flexor tendons and neurovascular structures were recorded. MRI demonstrated cord discontinuity, significant reduction of cord volume and a significant increase in cord signal intensity after treatment with collagenase. There was a slight increase in flexor tendon signal intensity that was not significant. These findings suggest that there may be local chemical dissolution of the cord. Future studies may establish whether or not this will have prognostic implications in terms of correction and recurrence following collagenase injection. LEVEL OF EVIDENCE: IV.


Asunto(s)
Contractura de Dupuytren/diagnóstico por imagen , Contractura de Dupuytren/tratamiento farmacológico , Imagen por Resonancia Magnética , Articulación Metacarpofalángica , Colagenasa Microbiana/uso terapéutico , Anciano , Estudios de Seguimiento , Humanos , Inyecciones Intralesiones , Masculino , Persona de Mediana Edad , Proyectos Piloto , Rango del Movimiento Articular , Resultado del Tratamiento
18.
Sci Rep ; 6: 36970, 2016 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-27845377

RESUMEN

Thermal transport of quantum magnets has elucidated the nature of low energy elementary excitations and complex interplay between those excited states via strong scattering of thermal carriers. BiCu2PO6 is a unique frustrated spin-ladder compound exhibiting highly anisotropic spin excitations that contain both itinerant and localized dispersion characters along the b- and a-axes respectively. Here, we investigate thermal conductivity κ of BiCu2PO6 under high magnetic fields (H) of up to 30 tesla. A dip-feature in κ, located at ~15 K at zero-H along all crystallographic directions, moves gradually toward lower temperature (T) with increasing H, thus resulting in giant suppression by a factor of ~30 near the critical magnetic field of Hc ≅ 23.5 tesla. The giant H- and T-dependent suppression of κ can be explained by the combined result of resonant scattering of phononic heat carriers with magnetic energy levels and increased phonon scattering due to enhanced spin fluctuation at Hc, unequivocally revealing the existence of strong spin-phonon coupling. Moreover, we find an experimental indication that the remaining magnetic heat transport along the b-axis becomes almost gapless at the magnetic quantum critical point realized at Hc.

19.
Biochim Biophys Acta ; 796(3): 354-8, 1984 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-6509082

RESUMEN

Relatively mild stimuli have been found to induce an appearance of the serum amyloid protein in the high-density lipoproteins (HDL) of rabbits. Large amounts of serum amyloid protein appeared in the HDL of rabbits, following intravenous infusions of the artificial triacylglycerol emulsion, Intralipid. Lesser, but still significant amounts of serum amyloid protein also appeared in rabbit HDL after intravenous infusions of sterile saline and even in non-infused rabbits that had been subjected to no more than serial blood sampling. Given that these latter procedures are necessary components of many metabolic experiments performed in vivo, the observation that they induce an appearance of serum amyloid protein in HDL has potentially major implications in terms of the interpretation of in vivo studies of HDL metabolism.


Asunto(s)
Amiloide/análisis , Lipoproteínas HDL/sangre , Proteína Amiloide A Sérica/análisis , Animales , Apolipoproteínas A/sangre , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Femenino , Peso Molecular , Conejos
20.
J Biomed Mater Res B Appl Biomater ; 73(2): 338-46, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15678489

RESUMEN

Various dental restorative composite resins containing 2,2-bis-[4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane (Bis-GMA) derivatives and spiro orthocarbonates (SOCs) were explored for minimizing the volumetric shrinkage that generally occurs during polymerization. Previous reports suggested mixing Bis-GMA with its derivative TMBis-GMA (2,2-bis[3,5-dimethyl-4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane) to obtain a dental composite with low volumetric shrinkage. It was hypothesized that spiro orthocarbonates would expand volumetrically during polymerization, because of their sophisticated ring-opening reactions; therefore several of them were added to the mixture of Bis-GMA and TMBis-GMA to bring about further reductions in volumetric shrinkage. It was indeed possible to reduce the extent of volumetric shrinkage of dental composites containing SOCs, and to do so without compromising these resins' mechanical properties.


Asunto(s)
Bisfenol A Glicidil Metacrilato/química , Resinas Compuestas/química , Materiales Biocompatibles/química , Bisfenol A Glicidil Metacrilato/síntesis química , Espectroscopía de Resonancia Magnética/métodos , Ensayo de Materiales , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad
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