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1.
Phys Rev Lett ; 122(22): 226601, 2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31283289

RESUMEN

The Lifshitz transition, a change in Fermi surface topology, is likely to greatly influence exotic correlated phenomena in solids, such as high-temperature superconductivity and complex magnetism. However, since the observation of Fermi surfaces is generally difficult in the strongly correlated systems, a direct link between the Lifshitz transition and quantum phenomena has been elusive so far. Here, we report a marked impact of the pressure-induced Lifshitz transition on thermoelectric performance for SnSe, a promising thermoelectric material without a strong electron correlation. By applying pressure up to 1.6 GPa, we have observed a large enhancement of the thermoelectric power factor by more than 100% over a wide temperature range (10-300 K). Furthermore, the high carrier mobility enables the detection of quantum oscillations of resistivity, revealing the emergence of new Fermi pockets at ∼0.86 GPa. The observed thermoelectric properties linked to the multivalley band structure are quantitatively reproduced by first-principles calculations, providing novel insight into designing the SnSe-related materials for potential valleytronic as well as thermoelectric applications.

2.
Dig Dis Sci ; 63(6): 1605-1612, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29564670

RESUMEN

BACKGROUND: According to the Japanese Esophageal Society (JES) guidelines, risk factors for lymph node (LN) metastasis in the muscularis mucosa (MM)/submucosa to a depth of up to 200 µm (SM1) in cases of esophageal squamous cell carcinomas (ESCCs) include the presence of lymphatic invasion (ly), venous invasion (v), infiltration pattern (INF)c, and SM1. The long-term prognoses of these patients are unclear, and there are very few reports on the validation of the curative criteria for MM/SM1 ESCCs. AIMS: To examine the long-term prognoses of these patients and the risk factors for LN metastasis of MM/SM1 ESCCs after endoscopic resection (ER). METHODS: This study included patients with MM/SM1 ESCCs who underwent ER at Hiroshima University Hospital from December 1990 to November 2016. We evaluated the clinicopathological characteristics of 98 patients and overall survival, disease-specific survival, recurrence-free survival, and recurrence rates in the e-curative and non-e-curative groups. RESULTS: The mean observation period was 75 months. There was no significant difference in disease-specific survival rate between the e-curative and non-e-curative groups (100 vs. 98%). There was no significant difference in disease-specific survival rates between the groups (100 vs. 98%). In contrast, the LN recurrence-free survival rate in patients with INFa, ly(-), and v(-) was significantly higher than that in patients with INFb/c, ly(+), or v(+) (100 and 87%, P < 0.05). CONCLUSION: Contrary to the JES guidelines, our findings suggest that new criteria (MM/SM1, INFa, negative vertical margin (VM0), ly[-], and v[-]) may be associated with curative ER without additional treatment.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/cirugía , Esofagectomía/métodos , Esofagoscopía , Anciano , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/secundario , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Esofagectomía/efectos adversos , Esofagectomía/mortalidad , Esofagoscopía/efectos adversos , Esofagoscopía/mortalidad , Femenino , Hospitales Universitarios , Humanos , Japón , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
3.
Dis Esophagus ; 31(7)2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29267962

RESUMEN

Endoscopic submucosal dissection (ESD) is a widely accepted procedure for superficial esophageal squamous cell carcinoma (SESCC) limited to the epithelium or lamina propria mucosae (EP/LPM). We aimed to compare the efficacy of endoscopic ultrasonography (EUS) and magnifying endoscopy with narrow band imaging (ME-NBI) for predicting the tumor invasion depth in patients with SESCC. Specifically, we evaluated the ability of these examinations to distinguish EP/LPM from SESCC invading the muscularis mucosae or superficial submucosa (MM/SM1) and more deeply invasive lesions before ESD.We retrospectively analyzed a database of all patients with SESCC who had undergone both EUS and ME-NBI for pretreatment staging and ESD resection at Hiroshima University Hospital between September 2007 and June 2015. The clinicopathologic characteristics of SESCCs were classified according to the Japanese Classification of Esophageal Cancer.A total of 174 lesions in 174 patients were included: 124 (71%) EP/LPMs, 35 (20%) MM/SM1s, and 15 (9%) SESCCs invading the mid submucosae (SM2). The sensitivity of EUS and of ME-NBI in distinguishing EP/LPM from MM/SM1 and more invasive lesions was 72% and 83%, respectively. The accuracy of EUS and ME-NBI in distinguishing EP/LPM from MM/SM1 and more invasive lesions was 70% and 82%, respectively. Sensitivity and accuracy of ME-NBI in distinguishing EP/LPM from MM/SM1 and more deeply invasive SESCCs is significantly higher than those of EUS (P = 0.048 and P = 0.017, respectively).ME-NBI may be more useful than EUS for the determination of SESCC invasion depth before ESD.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/patología , Endosonografía , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/patología , Esofagoscopía , Imagen de Banda Estrecha , Anciano , Carcinoma de Células Escamosas/cirugía , Resección Endoscópica de la Mucosa , Endosonografía/métodos , Mucosa Esofágica/diagnóstico por imagen , Mucosa Esofágica/patología , Neoplasias Esofágicas/cirugía , Carcinoma de Células Escamosas de Esófago , Esofagoscopía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen de Banda Estrecha/métodos , Invasividad Neoplásica/diagnóstico por imagen , Periodo Preoperatorio , Estudios Retrospectivos , Sensibilidad y Especificidad
4.
Exp Eye Res ; 143: 75-88, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26450656

RESUMEN

The aim of this study was to develop a novel in vivo corneal model of fibrosis in dogs utilizing alkali burn and determine the ability of suberanilohydroxamic acid (SAHA) to inhibit corneal fibrosis using this large animal model. To accomplish this, we used seven research Beagle dogs. An axial corneal alkali burn in dogs was created using 1 N NaOH topically. Six dogs were randomly and equally assigned into 2 groups: A) vehicle (DMSO, 2 µL/mL); B) anti-fibrotic treatment (50 µM SAHA). The degree of corneal opacity, ocular health, and anti-fibrotic effects of SAHA were determined utilizing the Fantes grading scale, modified McDonald-Shadduck (mMS) scoring system, optical coherence tomography (OCT), corneal histopathology, immunohistochemistry (IHC), and transmission electron microscopy (TEM). The used alkali burn dose to produce corneal fibrosis was well tolerated as no significant difference in mMS scores between control and treatment groups (p = 0.89) were detected. The corneas of alkali burned dogs showed significantly greater levels of α-smooth muscle actin, the fibrotic marker, than the controls (p = 0.018). Total corneal thickness of all dogs post-burn was significantly greater than baseline OCT images irrespective of treatment (p = 0.004); TEM showed that alkali burned corneas had significantly greater minimum and maximum interfibrillar distances than the controls (p = 0.026, p = 0.018). The tested topical corneal alkali burn dose generated significant opacity and fibrosis in dog corneas without damaging the limbus as evidenced by histopathology, IHC, TEM, and OCT findings, and represents a viable large animal corneal fibrosis in vivo model. Additional in vivo SAHA dosing studies with larger sample size are warranted.


Asunto(s)
Quemaduras Químicas/patología , Córnea/patología , Enfermedades de la Córnea/patología , Modelos Animales de Enfermedad , Actinas/metabolismo , Animales , Biomarcadores/metabolismo , Quemaduras Químicas/tratamiento farmacológico , Quemaduras Químicas/metabolismo , Córnea/metabolismo , Enfermedades de la Córnea/tratamiento farmacológico , Enfermedades de la Córnea/metabolismo , Perros , Quemaduras Oculares/inducido químicamente , Femenino , Fibrosis , Inhibidores de Histona Desacetilasas/uso terapéutico , Ácidos Hidroxámicos/uso terapéutico , Inmunohistoquímica , Hidróxido de Sodio/toxicidad , Tomografía de Coherencia Óptica , Vorinostat
7.
Int J Sports Med ; 33(2): 114-22, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22095322

RESUMEN

Physical activity has been shown to enhance endothelial function of central and peripheral vascular beds. The primary purpose of the present study was to test the hypothesis that a short-term exercise training program would result in enhanced endothelium-dependent vasorelaxation of a major artery supplying blood flow to the knee joint, the middle genicular artery. Female Yucatan miniature swine were randomly assigned into exercise trained (n=7) or sedentary (n=7) groups. Exercise trained pigs underwent a daily exercise training program on treadmills for 7 days. In vitro assessment of vasorelaxation was determined in a dose response manner by administrating increasing doses of 3 different dilators; adenosine diphosphate, bradykinin, and sodium nitroprusside. The role of nitric oxide synthase and cyclooxygenase pathways in vasomotor responses was evaluated with specific inhibitors using nitro-L-arginine methyl ester and indomethacin incubation, respectively. The results of this investigation indicate that adenosine and bradykinin-induced endothelium-dependent vasorelaxation were significantly enhanced in middle genicular artery from exercise trained pigs (p<0.05). Endothelium-independent vasorelaxation was not altered with exercise training as determined by the response to sodium nitroprusside. The findings of the present investigation indicate that short-term exercise training enhances endothelial function of middle genicular artery through adaptations in the nitric oxide synthase and by non-nitric oxide synthase, non-cyclooxygenase pathways.


Asunto(s)
Articulación de la Rodilla/irrigación sanguínea , Condicionamiento Físico Animal/fisiología , Vasodilatación/fisiología , Adenosina Difosfato/farmacología , Animales , Bradiquinina/farmacología , Endotelio Vascular/metabolismo , Femenino , Óxido Nítrico Sintasa/metabolismo , Nitroprusiato/farmacología , Distribución Aleatoria , Porcinos , Porcinos Enanos , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología
8.
Virus Evol ; 8(2): veac075, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36533148

RESUMEN

HIV-2 infection will progress to AIDS in most patients without treatment, albeit at approximately half the rate of HIV-1 infection. HIV-2 capsid (p26) amino acid polymorphisms are associated with lower viral loads and enhanced processing of T cell epitopes, which may lead to protective Gag-specific T cell responses common in slower progressors. Lower virus evolutionary rates, and positive selection on conserved residues in HIV-2 env have been associated with slower progression to AIDS. In this study we analysed 369 heterochronous HIV-2 p26 sequences from 12 participants with a median age of 30 years at enrolment. CD4% change over time was used to stratify participants into relative faster and slower progressor groups. We analysed p26 sequence diversity evolution, measured site-specific selection pressures and evolutionary rates, and determined if these evolutionary parameters were associated with progression status. Faster progressors had lower CD4% and faster CD4% decline rates. Median pairwise sequence diversity was higher in faster progressors (5.7x10-3 versus 1.4x10-3 base substitutions per site, P<0.001). p26 evolved under negative selection in both groups (dN/dS=0.12). Median virus evolutionary rates were higher in faster than slower progressors - synonymous rates: 4.6x10-3 vs. 2.3x10-3; and nonsynonymous rates: 6.9x10-4 vs. 2.7x10-4 substitutions/site/year, respectively. Virus evolutionary rates correlated negatively with CD4% change rates (ρ = -0.8, P=0.02), but not CD4% level. The signature amino acid at p26 positions 6, 12 and 119 differed between faster (6A, 12I, 119A) and slower (6G, 12V, 119P) progressors. These amino acid positions clustered near to the TRIM5α/p26 hexamer interface surface. p26 evolutionary rates were associated with progression to AIDS and were mostly driven by synonymous substitutions. Nonsynonymous evolutionary rates were an order of magnitude lower than synonymous rates, with limited amino acid sequence evolution over time within hosts. These results indicate HIV-2 p26 may be an attractive therapeutic target.

9.
Osteoarthritis Cartilage ; 19(9): 1142-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21736944

RESUMEN

OBJECTIVE: To test the hypothesis that changes in subchondral bone are significantly different among three canine models of osteoarthritis (OA). DESIGN: In 21 purpose-bred mongrel dogs, OA was induced in one knee joint via either anterior cruciate ligament transection (ACLt; n = 5), medial femoral condylar groove creation (GR; n = 6), or medial meniscal release (MR; n = 5). Five dogs that had sham surgery (SH; n = 5) in one knee joint served as controls. Lameness scoring was performed every 4 weeks. Twelve weeks after surgery, the knee joints were examined by histology and histomorphometry. RESULTS: Articular cartilage pathology as determined by Mankin scores was significantly severe in all three OA models compared to SH controls in the medial tibia (P < 0.001 to P = 0.026). ACLt had significantly thinner subchondral plate thickness (Sp.Th) in both the medial and lateral tibias while MR had significantly thicker Sp.Th in the medial tibia compared to SH controls (P < 0.001 to P = 0.011). Trabecular bone volume (BV/TV) and trabecular bone thickness (Tb.Th) for ACLt were significantly less than SH controls in the tibias (P < 0.001 to P = 0.011). Tibial Sp.Th, BV/TV, and Tb.Th were all moderately to strongly correlated with lameness scores obtained throughout the study period (r = -0.436 to r = -0.738, P < 0.001 to P = 0.047) while Mankin scores showed moderate to strong correlations with Sp.Th in each OA model (r = 0.465 to r = 0.816, P < 0.001 to P = 0.033). CONCLUSIONS: Changes in Sp.Th are associated with articular cartilage damage while tibial Sp.Th and BV/TV and Tb.Th appear to be all influenced by joint loading alterations.


Asunto(s)
Cartílago Articular/patología , Osteoartritis de la Rodilla/patología , Tibia/patología , Animales , Ligamento Cruzado Anterior/patología , Ligamento Cruzado Anterior/cirugía , Modelos Animales de Enfermedad , Perros , Femenino , Miembro Posterior/patología , Cojera Animal/patología , Meniscos Tibiales/patología , Meniscos Tibiales/cirugía
10.
Phys Rev Lett ; 106(6): 067003, 2011 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-21405487

RESUMEN

A neutron scattering study of heavily hole-overdoped superconducting KFe2As2 revealed a well-defined low-energy incommensurate spin fluctuation at [π(1 ± 2 δ),0] with δ = 0.16. The incommensurate structure differs from the previously observed commensurate peaks in electron-doped AFe2As2 (A = Ba, Ca, or Sr) at low energies. The direction of the peak splitting is perpendicular to that observed in Fe(Te,Se) or in Ba(Fe,Co)2As2 at high energies. A band structure calculation suggests interband scattering between bands around the Γ and X points as an origin of this incommensurate peak. The perpendicular direction of the peak splitting can be understood within the framework of multiorbital band structure. The results suggest that spin fluctuation is more robust in hole-doped than in electron-doped samples, which can be responsible for the appearance of superconductivity in the heavily hole-doped samples.

11.
Osteoarthritis Cartilage ; 18 Suppl 3: S66-79, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20864024

RESUMEN

The dog is a common model for study of osteoarthritis (OA). Subjective histologic scoring systems have often served as the reference standard for presence and severity of OA. However, these scoring systems have perceived shortcomings. The system developed for this report attempts to address these shortcomings by providing a standardized methodology for global assessment of the joint, versatility and the potential for relative weighting of pathology, allowing for comparison among time points, studies, and centers, and critical analysis of the system's reliability. The proposed system for assessment of canine tissues appears to provide an effective method for global assessment of articular pathology in OA. The system is versatile, comprehensive, and reliable and appears to have advantages over conventional scoring systems.


Asunto(s)
Artritis Experimental/patología , Osteoartritis/patología , Animales , Cartílago Articular/patología , Modelos Animales de Enfermedad , Perros , Articulaciones/patología , Meniscos Tibiales/patología , Índice de Severidad de la Enfermedad , Membrana Sinovial/patología
12.
Vet Pathol ; 47(5): 944-7, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20466862

RESUMEN

An 8-year-old castrated male mixed-breed dog had an ill-defined hemorrhagic and painful lesion in the base of the claw of the second digit of the right forelimb. Radiographically, the expansile and lytic lesion affected the distal phalanx. The digit was amputated and submitted for histologic examination. Histologically, the distal phalanx was largely replaced by a mass composed of variably sized cavernous vascular spaces lined by a single layer of flattened endothelial cells. A similar mass was in the subcutis adjacent to the distal phalanx. The benign vascular proliferation involving the medulla of bone and a second tissue type in this dog is consistent with skeletal-extraskeletal angiomatosis as described in humans. To the authors' knowledge, this is the first report of skeletal-extraskeletal angiomatosis in the veterinary literature.


Asunto(s)
Angiomatosis/veterinaria , Enfermedades de los Perros/patología , Enfermedades del Pie/veterinaria , Amputación Quirúrgica/veterinaria , Angiomatosis/patología , Angiomatosis/cirugía , Animales , Enfermedades de los Perros/cirugía , Perros , Enfermedades del Pie/patología , Enfermedades del Pie/cirugía , Inmunohistoquímica/veterinaria , Masculino
13.
Genes Immun ; 9(3): 214-23, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18273033

RESUMEN

Leukocyte immunoglobulin-like receptors (LILRs) are inhibitory, stimulatory or soluble receptors encoded within the leukocyte receptor complex. Some LILRs are extensively polymorphic, and exhibit evidence for balancing selection and association with disease susceptibility. LILRA2 (LIR7/ILT1) is an activating receptor highly expressed in inflammatory tissues, and is involved in granulocyte and macrophage activation. In this study, we examined the association of LILRA2 and adjacently located LILRA1 with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and microscopic polyangiitis (MPA). Polymorphism screening detected a LILRA2 SNP (rs2241524 G>A) that disrupts splice acceptor site of intron 6. Case-control association studies on 273 Japanese SLE, 296 RA, 50 MPA and 284 healthy individuals revealed increase of genotype A/A in SLE (12.1%, odds ratio (OR) 1.82, 95% confidence interval (CI) 1.02-3.24, P=0.041) and in MPA (16.0%, OR 2.52, 95% CI 1.07-5.96, P=0.049) compared with healthy individuals (7.0%). The risk allele caused an activation of a cryptic splice acceptor site that would lead to a novel LILRA2 isoform lacking three amino acids in the linker region (Delta 419-421). Flow cytometry indicated that this isoform was expressed on the surface of monocytes. These findings suggested that LILRA2 Delta 419-421 isoform encoded by the splice site SNP may play a role in SLE and MPA.


Asunto(s)
Empalme Alternativo/genética , Pueblo Asiatico/genética , Predisposición Genética a la Enfermedad/genética , Lupus Eritematoso Sistémico/genética , Receptores Inmunológicos/genética , Vasculitis/genética , Secuencia de Bases , Cartilla de ADN/genética , Citometría de Flujo , Genotipo , Humanos , Datos de Secuencia Molecular , Monocitos/metabolismo , Oportunidad Relativa , Polimorfismo de Nucleótido Simple/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN
14.
Kyobu Geka ; 61(5): 398-402, 2008 May.
Artículo en Japonés | MEDLINE | ID: mdl-18464487

RESUMEN

We report an unusual clinical presentation of ruptured proximal aorta as a left hemothorax after operation for type A dissection. A 74-year-old man who had undergone ascending aortic replacement for acute type A dissection 4 months previously developed a loss of consciousness followed by shock state. Both chest X-ray and computed tomography (CT) scan revealed opacified left hemothorax. The patient died during a diagnostic procedure. Post mortem examination showed rupture of proximal aortic dissection extended to the left pleural cavity path through the right atrial wall and the right ventricular wall.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Disección Aórtica/cirugía , Rotura de la Aorta , Hemotórax , Complicaciones Posoperatorias , Enfermedad Aguda , Anciano , Rotura de la Aorta/diagnóstico , Rotura de la Aorta/patología , Resultado Fatal , Hemotórax/diagnóstico , Hemotórax/etiología , Hemotórax/patología , Humanos , Masculino , Radiografía Torácica , Tomografía Computarizada por Rayos X
15.
Dalton Trans ; 47(45): 16205-16210, 2018 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-30387487

RESUMEN

As-Based Zintl compounds Ba1-xKxCd2As2 crystallized in the CaAl2Si2-type structure (space group P3[combining macron]m1) were prepared using solid-state reactions followed by hot-pressing. We have successfully substituted K for Ba up to x = 0.08, producing hole-carrier doping with concentrations up to 1.60 × 1020 cm-3. We have determined the band-gap value of non-doped BaCd2As2 to be 0.40 eV from the temperature dependence of the electrical resistivity. Both the electrical resistivity and the Seebeck coefficient decrease with hole doping, leading to a power factor value of 1.28 mW m-1 K-2 at 762 K for x = 0.04. A first-principles band calculation shows that the relatively large power factor mainly originates from the two-fold degeneracy of the bands comprising As px,y orbitals and from the anisotropic band structure at the valence-band maximum. The lattice thermal conductivity is suppressed by the K doping to 0.46 W m-1 K-1 at 773 K for x = 0.08, presumably due to randomness. The effect of randomness is compensated by an increase in the electronic thermal conductivity, which keeps the total thermal conductivity approximately constant. In consequence, the dimensionless figure-of-merit ZT reaches a maximum value of 0.81 at 762 K for x = 0.04.

16.
Mol Cell Biol ; 9(10): 4459-66, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2586518

RESUMEN

The preS1 surface glycoprotein of hepatitis B virus is targeted to the endoplasmic reticulum (ER) and is retained in this organelle when expressed in the absence of other viral gene products. The protein is also acylated at its N terminus with myristic acid. Sequences responsible for its ER retention have been identified through examination of mutants bearing lesions in the preS1 coding region. These studies reveal that such sequences map to the N terminus of the molecule, between residues 6 and 19. Molecules in which this region was present remained in the ER; those in which it had been deleted were secreted from the cell. Although all deletions which allowed efficient secretion also impaired acylation of the polypeptide, myristylation alone was not sufficient for ER retention: point mutations which eliminated myristylation did not lead to secretion. These data indicate that an essential element for ER retention resides in a 14-amino-acid sequence that is unrelated to previously described ER retention signals.


Asunto(s)
Retículo Endoplásmico/metabolismo , Glicoproteínas/metabolismo , Virus de la Hepatitis B/metabolismo , Señales de Clasificación de Proteína/genética , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Línea Celular , Datos de Secuencia Molecular , Mutación , Ácidos Mirísticos/metabolismo , Plásmidos , Transfección
17.
J Phys Condens Matter ; 19(36): 365204, 2007 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-21694150

RESUMEN

By means of a combination of the local density approximation and dynamical mean field theory (LDA + DMFT), we study the possibility of making a d(1) analogue of d(9) cuprates on the basis of Sr(2)VO(4). We calculate the electronic structure of Sr(2)VO(4) under pressure, and show that while the material is a 1/6-filled three-band system at ambient pressure with a small level splitting between the d(xy)- and d(yz/zx)-bands, an orbital polarization occurs under sufficiently high uniaxial pressure in the c-direction. While all energy scales are relatively small, the electronic structure of Sr(2)VO(4) under pressure is similar to that of La(2)CuO(4); it is a two-dimensional half-filled single-band system which has, relative to the nearest neighbour hopping, a similar Coulomb repulsion and next-nearest neighbour hopping. We also study the effect of substituting Sr by Ba, i.e., chemical pressure, and show that the pressure needed for the orbital polarization is considerably reduced.

18.
J Vet Intern Med ; 30(3): 813-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26968732

RESUMEN

BACKGROUND: A variety of presumed hereditary, neurologic diseases have been reported in young Rottweilers. Overlapping ages of onset and clinical signs have made antemortem diagnosis difficult. One of these diseases, neuronal vacuolation and spinocerebellar degeneration (NVSD) shares clinical and histological features with polyneuropathy with ocular abnormalities and neuronal vacuolation (POANV), a recently described hereditary disease in Black Russian Terriers (BRTs). Dogs with POANV harbor mutations in RAB3GAP1 which codes for a protein involved in membrane trafficking. HYPOTHESIS: Rottweilers with NVSD will be homozygous for the RAB3GAP1:c.743delC allele associated with POANV in BRTs. ANIMALS: Eight Rottweilers with NVSD confirmed at necropsy, 128 Rottweilers without early onset neurologic signs, and 468 randomly selected dogs from 169 other breeds. METHODS: Retrospective case-control study. Dogs were genotyped for the RAB3GAP1:c.743delC allele with an allelic discrimination assay. RESULTS: All 8 NVSD-affected dogs were homozygous for the RAB3GAP1:c.743delC allele while the 128 NVSD-free Rottweilers were either homozygous for the reference allele (n = 105) or heterozygous (n = 23) and the 468 genotyped dogs from other breeds were all homozygous for the reference allele. CONCLUSIONS AND CLINICAL IMPORTANCE: The RAB3GAP1:c.743delC mutation is associated with a similar phenotype in Rottweilers and BRTs. Identification of the mutation permits a DNA test that can aid in the diagnosis of NVSD and identify carriers of the trait so that breeders can avoid producing affected dogs. Disruption of membrane trafficking could explain the neuronal vacuolation seen in NVSD and other spongiform encephalopathies.


Asunto(s)
Enfermedades de los Perros/genética , Degeneraciones Espinocerebelosas/veterinaria , Proteínas de Unión al GTP rab3/genética , Animales , Enfermedades de los Perros/patología , Perros , Genotipo , Mutación , Neuronas/patología , Polineuropatías/genética , Polineuropatías/patología , Polineuropatías/veterinaria , Estudios Retrospectivos , Degeneraciones Espinocerebelosas/genética , Degeneraciones Espinocerebelosas/patología
19.
Sci Rep ; 6: 26394, 2016 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-27216477

RESUMEN

Iron-based compounds (IBS) display a surprising variety of superconducting properties that seems to arise from the strong sensitivity of these systems to tiny details of the lattice structure. In this respect, systems that become superconducting under pressure, like CaFe2As2, are of particular interest. Here we report on the first directional point-contact Andreev-reflection spectroscopy (PCARS) measurements on CaFe2As2 crystals under quasi-hydrostatic pressure, and on the interpretation of the results using a 3D model for Andreev reflection combined with ab-initio calculations of the Fermi surface (within the density functional theory) and of the order parameter symmetry (within a random-phase-approximation approach in a ten-orbital model). The almost perfect agreement between PCARS results at different pressures and theoretical predictions highlights the intimate connection between the changes in the lattice structure, a topological transition in the holelike Fermi surface sheet, and the emergence on the same sheet of an order parameter with a horizontal node line.

20.
J Int Med Res ; 33(2): 133-49, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15790125

RESUMEN

Cardiopulmonary bypass (CPB) contributes to a morbidity-inducing systemic inflammatory response after cardiac surgery. We compared this response in patients receiving coronary artery bypass grafting (CABG) with (CPB group; n = 7) or without (off-pump group; n = 8) the Minimal Extracorporeal Circulation (MECC) system. Serum concentrations of tumour necrosis factor (TNF)-alpha, soluble TNF receptors, pro- and anti-inflammatory interleukins (ILs) and other myocardial injury markers were measured after anaesthetic induction, at 1 h, 4 h and 24 h after completing all anastomoses or serially. Soluble TNF receptor type I (sTNFRI) and IL-8 peaked early after CABG in both groups and did not decline. Serum sTNFRI was significantly higher in the CPB compared with the off-pump group at 1 h, whereas IL-8 was significantly lower in the CPB group throughout. The MECC system, therefore, produces an equivalent acute cytokine response and degree of myocardial injury to off-pump CABG, and may be useful when CABG cannot be performed without CPB.


Asunto(s)
Puente de Arteria Coronaria/métodos , Citocinas/biosíntesis , Circulación Extracorporea , Anciano , Citocinas/sangre , Humanos , Inflamación , Interleucina-8/sangre , Interleucinas/metabolismo , Masculino , Persona de Mediana Edad , Neutrófilos/metabolismo , Receptores Tipo II del Factor de Necrosis Tumoral/biosíntesis , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo
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