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1.
Phys Rev Lett ; 126(17): 175503, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33988455

RESUMEN

In situ femtosecond x-ray diffraction measurements and ab initio molecular dynamics simulations were performed to study the liquid structure of tantalum shock released from several hundred gigapascals (GPa) on the nanosecond timescale. The results show that the internal negative pressure applied to the liquid tantalum reached -5.6 (0.8) GPa, suggesting the existence of a liquid-gas mixing state due to cavitation. This is the first direct evidence to prove the classical nucleation theory which predicts that liquids with high surface tension can support GPa regime tensile stress.

2.
J Chem Phys ; 142(16): 164504, 2015 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-25933771

RESUMEN

Pressure, density, and temperature data for H2O were obtained up to 260 GPa by using laser-driven shock compression technique. The shock compression technique combined with the diamond anvil cell was used to assess the equation of state models for the P-ρ-T conditions for both the principal Hugoniot and the off-Hugoniot states. The contrast between the models allowed for a clear assessment of the equation of state models. Our P-ρ-T data totally agree with those of the model based on quantum molecular dynamics calculations. These facts indicate that this model is adopted as the standard for modeling interior structures of Neptune, Uranus, and exoplanets in the liquid phase in the multi-Mbar range.

3.
Br J Cancer ; 110(1): 156-63, 2014 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-24253505

RESUMEN

BACKGROUND: Transforming growth factor-ß (TGF-ß) is a major inducer of epithelial-mesenchymal transition (EMT) in different cell types. TGF-ß-mediated EMT is thought to contribute to tumour cell spread and metastasis. Sialyl Lewis antigens synthesised by fucosyltransferase (FUT) 3 and FUT6 are highly expressed in patients with metastatic colorectal cancer (CRC) and are utilised as tumour markers for cancer detection and evaluation of treatment efficacy. However, the role of FUT3 and FUT6 in augmenting the malignant potential of CRC induced by TGF-ß is unclear. METHODS: Colorectal cancer cell lines were transfected with siRNAs for FUT3/6 and were examined by cell proliferation, invasion and migration assays. The expression and phosphorylation status of TGF-ß downstream molecules were analysed by western blot. Fucosylation of TGF-ß receptor (TßR) was examined by lectin blot analysis. RESULTS: Inhibition of FUT3/6 expression by siRNAs suppressed the fucosylation of type I TßR and phosphorylation of the downstream molecules, thereby inhibiting the invasion and migration of CRC cells by EMT. CONCLUSION: Fucosyltransferase 3/6 has an essential role in cancer cell adhesion to endothelial cells by upregulation of sialyl Lewis antigens and also by enhancement of cancer cell migration through TGF-ß-mediated EMT.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Fucosiltransferasas/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Adhesión Celular/fisiología , Línea Celular Tumoral , Neoplasias Colorrectales/enzimología , Neoplasias Colorrectales/patología , Transición Epitelial-Mesenquimal , Fucosiltransferasas/genética , Células HT29 , Humanos , Fosforilación , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , Transducción de Señal , Proteínas Smad/metabolismo , Transfección , Factor de Crecimiento Transformador beta/farmacología , Regulación hacia Arriba
4.
J Phys Chem Lett ; 14(27): 6241-6247, 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37401781

RESUMEN

Solution-state nuclear magnetic resonance spectroscopy (NMR) is a powerful method for the analysis of intermolecular interactions within a biomolecular system. However, low sensitivity is one of the major obstacles of NMR. We improved the sensitivity of solution-state 13C NMR for the observation of intermolecular interactions between protein and ligand using hyperpolarized solution samples at room temperature. Eutectic crystals composed of 13C-salicylic acid and benzoic acid doped with pentacene were hyperpolarized by dynamic nuclear polarization using photoexcited triplet electrons, and a 13C nuclear polarization of 0.72 ± 0.07% was achieved after dissolution. The binding of human serum albumin and 13C-salicylate was observed with several hundred times sensitivity enhancement under mild conditions. The established 13C NMR was applied for pharmaceutical NMR experiments by observation of the partial return of the 13C chemical shift of salicylate by competitive binding with other non-isotope-labeled drugs.


Asunto(s)
Proteínas , Ácido Salicílico , Humanos , Ligandos , Solubilidad , Espectroscopía de Resonancia Magnética/métodos , Proteínas/química , Resonancia Magnética Nuclear Biomolecular/métodos
5.
J Phys Chem B ; 126(19): 3530-3538, 2022 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-35538043

RESUMEN

Dissolution dynamic nuclear polarization has been applied in various fields, including chemistry, biology, and medical science. To expand the scope of these applications, the nuclear singlet state, which is decoherence-free against dipolar relaxation between spin pairs, has been studied experimentally, theoretically, and numerically. The singlet state composed of proton spins is used in several applications, such as enhanced polarization preservation, molecular tagging to probe slow dynamic processes, and detection of ligand-protein complexes. In this study, we predict the lifetimes of the nuclear spin states composed of proton spin pairs using the molecular dynamics method and quantum chemistry simulations. We consider intramolecular dipolar, intermolecular dipolar between solvent and solute, chemical shift anisotropy, and spin-rotation interactions. In particular, the relaxation rate of intermolecular dipolar interactions is calculated using the molecular dynamics method for various solvents. The calculated values and the experimental values are of the same order of magnitude. Our program would provide insight into the molecular design of several NMR applications and would be helpful in predicting the nuclear spin relaxation time of synthetic molecules in advance.


Asunto(s)
Simulación de Dinámica Molecular , Protones , Espectroscopía de Resonancia Magnética/métodos , Soluciones , Solventes
6.
Nat Commun ; 12(1): 2679, 2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-33976145

RESUMEN

Turbulence is ubiquitous in the universe and in fluid dynamics. It influences a wide range of high energy density systems, from inertial confinement fusion to astrophysical-object evolution. Understanding this phenomenon is crucial, however, due to limitations in experimental and numerical methods in plasma systems, a complete description of the turbulent spectrum is still lacking. Here, we present the measurement of a turbulent spectrum down to micron scale in a laser-plasma experiment. We use an experimental platform, which couples a high power optical laser, an x-ray free-electron laser and a lithium fluoride crystal, to study the dynamics of a plasma flow with micrometric resolution (~1µm) over a large field of view (>1 mm2). After the evolution of a Rayleigh-Taylor unstable system, we obtain spectra, which are overall consistent with existing turbulent theory, but present unexpected features. This work paves the way towards a better understanding of numerous systems, as it allows the direct comparison of experimental results, theory and numerical simulations.

7.
Sci Rep ; 9(1): 10155, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31300690

RESUMEN

Water, methane, and ammonia are commonly considered to be the key components of the interiors of Uranus and Neptune. Modelling the planets' internal structure, evolution, and dynamo heavily relies on the properties of the complex mixtures with uncertain exact composition in their deep interiors. Therefore, characterising icy mixtures with varying composition at planetary conditions of several hundred gigapascal and a few thousand Kelvin is crucial to improve our understanding of the ice giants. In this work, pure water, a water-ethanol mixture, and a water-ethanol-ammonia "synthetic planetary mixture" (SPM) have been compressed through laser-driven decaying shocks along their principal Hugoniot curves up to 270, 280, and 260 GPa, respectively. Measured temperatures spanned from 4000 to 25000 K, just above the coldest predicted adiabatic Uranus and Neptune profiles (3000-4000 K) but more similar to those predicted by more recent models including a thermal boundary layer (7000-14000 K). The experiments were performed at the GEKKO XII and LULI2000 laser facilities using standard optical diagnostics (Doppler velocimetry and optical pyrometry) to measure the thermodynamic state and the shock-front reflectivity at two different wavelengths. The results show that water and the mixtures undergo a similar compression path under single shock loading in agreement with Density Functional Theory Molecular Dynamics (DFT-MD) calculations using the Linear Mixing Approximation (LMA). On the contrary, their shock-front reflectivities behave differently by what concerns both the onset pressures and the saturation values, with possible impact on planetary dynamos.

8.
Ann N Y Acad Sci ; 1134: 120-45, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18566092

RESUMEN

Extraction of oil from the Alberta Oil Sands through surface mining involves the removal of the overburden and oil sand to a depth of up to 100 m and over extremely large areas. While the operation of the bitumen processing plants has serious environmental impacts on downstream habitats, this article focuses on the reclamation of areas from which the oil sands have been removed, processed, and returned. This reclamation following closure of the mines will entail the complete re-creation of landforms and ecosystems at a landscape scale, with the goal of producing suitable habitats for plants, animals, and people. Such projects will require a reasonable understanding of the geophysical and ecological processes that operate at a wide range of scales. Some information is provided on the climate, hydrology, vegetation, and land use (past and current) of the Oil Sands area, situated within the Boreal Plain ecozone, to provide a framework for discussion of issues to be addressed in, and proposed guidelines for, such large-scale reclamation. Although none of the mines has yet closed, numerous consultant reports have been produced with recommendations for various aspects of such reclamation projects (e.g., wetland hydrology, vegetation, wildlife habitat). The scientific basis of such reports is found to vary with respect to depth of understanding of the relevant processes.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Ecosistema , Minería/métodos , Petróleo , Alberta , Conservación de los Recursos Naturales/legislación & jurisprudencia , Fenómenos Geológicos , Geología , Minería/legislación & jurisprudencia
9.
Gynecol Obstet Invest ; 66(1): 12-3, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18230909

RESUMEN

A rare case of a 31-year-old woman is reported who had massive intraperitoneal bleeding caused by ovarian hemorrhage as the first manifestation of acute leukemia. Preoperative laboratory findings revealed severe anemia (Hb 6.6 g/dl) and thrombocytopenia (1.5 x 10(4)/mm(3)) but normal leukocyte count (3.9 x 10(3)/mm(3)). After surgery, blast cells were found in her peripheral blood and she was diagnosed with M0 type acute myeloid leukemia. In addition, histopathology revealed infiltration of leukemic cells in the resected ovary.


Asunto(s)
Hemoperitoneo/etiología , Leucemia Mieloide Aguda/patología , Neoplasias Ováricas/secundario , Adulto , Femenino , Humanos , Neoplasias Ováricas/cirugía
10.
Sci Rep ; 8(1): 16407, 2018 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-30401885

RESUMEN

High resolution X-ray imaging is crucial for many high energy density physics (HEDP) experiments. Recently developed techniques to improve resolution have, however, come at the cost of a decreased field of view. In this paper, an innovative experimental detector for X-ray imaging in the context of HEDP experiments with high spatial resolution, as well as a large field of view, is presented. The platform is based on coupling an X-ray backligther source with a Lithium Fluoride detector, characterized by its large dynamic range. A spatial resolution of 2 µm over a field of view greater than 2 mm2 is reported. The platform was benchmarked with both an X-ray free electron laser (XFEL) and an X-ray source produced by a short pulse laser. First, using a non-coherent short pulse laser-produced backlighter, reduced penumbra blurring, as a result of the large size of the X-ray source, is shown. Secondly, we demonstrate phase contrast imaging with a fully coherent monochromatic XFEL beam. Modeling of the absorption and phase contrast transmission of X-ray radiation passing through various targets is presented.

11.
J Biomed Mater Res A ; 81(2): 310-6, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17120215

RESUMEN

The effects of an oral p38 mitogen-activated protein kinase (MAPK) inhibitor and polyethylene particles separately and together on tissue differentiation in the bone harvest chamber (BHC) in rabbits over a 3-week treatment period were investigated. The harvested tissue was analyzed histomorphometrically for markers of bone formation (percentage of bone area), osteoblasts (alkaline phosphatase staining), and osteoclasts (CD51, the alpha chain of the vitronectin receptor). Polyethylene particles decreased the percentage of bone ingrowth and staining for alkaline phosphatase. The p38 MAPK inhibitor alone decreased alkaline phosphatase staining. When the oral p38 MAPK inhibitor was given and the chamber contained polyethylene particles, there was a suppression of bone ingrowth and alkaline phosphatase staining. In contrast to oral non-steroidal anti-inflammatory drugs (NSAIDs) and local Interleukin-1 receptor antagonist (IL-1ra) administration, the oral p38 MAPK inhibitor alone did not suppress bone formation when given during the initial phase of tissue differentiation. Particle-induced inflammation and the foreign body reaction were not curtailed when the p38 MAPK inhibitor was given simultaneously with particles. Additional experiments are needed to establish the efficacy of p38 MAPK inhibitor administration on mitigating an established inflammatory and foreign body reaction that parallels the clinical situation more closely.


Asunto(s)
Oseointegración/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Administración Oral , Animales , Materiales Biocompatibles , Cámaras de Difusión de Cultivos , Prótesis Articulares/efectos adversos , Masculino , Ensayo de Materiales , Osteólisis/etiología , Osteólisis/prevención & control , Polietilenos , Falla de Prótesis , Inhibidores de Proteínas Quinasas/administración & dosificación , Conejos , Tibia/patología , Tibia/cirugía , Ingeniería de Tejidos
12.
Biomaterials ; 27(21): 3882-7, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16540164

RESUMEN

The pro-angiogenic cytokine vascular endothelial growth factor (VEGF) has been implicated in periprosthetic osteolysis and subsequent aseptic loosening of implants following total hip arthroplasty (THA). The goal of this study was to investigate whether increased VEGF at the bone-implant interface is secondary to a greater number of VEGF-producing cells or to increased VEGF production by individual cells. Real time polymerase chain reaction (RT-PCR) techniques were used to assess the expression of VEGF mRNA (isoforms 121, 165, 189) in periprosthetic tissues from revision THAs. Immunofluorescence was used to determine both differences in overall cellularity and in VEGF-producing cell type (macrophages, fibroblasts, endothelial cells) between patients with periprosthetic osteolysis (OL) and a control group undergoing primary THA for osteoarthritis (OA). Quantitative analysis of VEGF release in periprosthetic membranes via RT-PCR demonstrated no significant difference in the per-cell mRNA production of VEGF isoforms 121 165, or 189 between OL and OA patient groups. Immunofluorescence showed both higher cellularity and higher overall VEGF expression in the OL group. Immunofluorescence also showed a significant increase in macrophages in the OL group, but no significant difference in the proportion of fibroblasts or endothelial cells between the OL and OA groups. Co-localization of CD68+ and CD11b+ macrophage fluorescent signals with VEGF signal was greater in the OL group than in the OA group. Our results demonstrate that increased VEGF in OL periprosthetic tissue compared to OA synovium is correlated to increased numbers of VEGF-producing CD68+ and CD11b+ macrophages. Impact statement: Aseptic loosening, caused in large part by OL, remains the major cause of failed THAs leading to revision surgery. At the bone-implant interface, we found increased numbers of macrophages-cellular mediators of OL-and increased VEGF expression. VEGF may be a possible target for therapeutic intervention in mitigating OL.


Asunto(s)
Osteoartritis/metabolismo , Osteoartritis/patología , Osteólisis/metabolismo , Osteólisis/patología , Infecciones Relacionadas con Prótesis/metabolismo , Infecciones Relacionadas con Prótesis/patología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Anciano , Anciano de 80 o más Años , Células Cultivadas , Femenino , Prótesis de Cadera/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/etiología , Osteoartritis/cirugía , Osteólisis/etiología , Infecciones Relacionadas con Prótesis/etiología
13.
Leukemia ; 19(9): 1558-66, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16034467

RESUMEN

We investigated the cause of myelofibrosis and proliferation of megakaryocytes in myelodysplastic syndrome with myelofibrosis (MDS-MF (+)). Plasma-transforming growth factor-beta1 (PTGF-beta1) concentrations closely correlated with myelofibrosis grade in MDS-MF (+) and were higher than those in idiopathic myelofibrosis (IMF), essential thrombocythemia (ET), idiopathic thrombocytopenic purpura (ITP), MDS-without MF (MDS-MF (-)) or healthy volunteers (HV). Peripheral blood mononuclear cells from MDS-MF (+) patients expressed more TGF-beta1 mRNA than those from IMF, MDS-MF (-) or HV. When we immunostained bone marrow specimens of MDS-MF (+) for TGF-beta, the intensity of blasts was apparently higher than that of megakaryocytes, while in MDS-MF (-), megakaryocytes were immunostained with a similar intensity as that in MDS-MF (+), but blasts were negative for staining. In IMF, megakaryocytes, monocytes and small mononuclear cells representing CD34+ cells were all similarly stained with a much lower intensity than that of blasts in MDS-MF (+). The number of bone marrow megakaryocytes were increased the most in MDS-MF (+), followed by ET, ITP, MDS-MF (-) and NHL and correlated with plasma thrombopoietin (TPO) levels or with plasma TGF-beta1 levels, respectively, in each disease. Thus, in MDS-MF (+), both myelofibrosis and the increased megakaryocytes were ascribed to overproduction of TGF-beta1 from blasts.


Asunto(s)
Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/inmunología , Mielofibrosis Primaria/inmunología , Trombopoyetina/inmunología , Factor de Crecimiento Transformador beta/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD34/biosíntesis , Antígenos CD34/genética , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/patología , Recuento de Células , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Leucocitos Mononucleares/metabolismo , Masculino , Megacariocitos/citología , Megacariocitos/patología , Persona de Mediana Edad , Síndromes Mielodisplásicos/complicaciones , Mielofibrosis Primaria/complicaciones , ARN Mensajero/genética , Trombopoyetina/biosíntesis , Trombopoyetina/sangre , Factor de Crecimiento Transformador beta/biosíntesis , Factor de Crecimiento Transformador beta/sangre
14.
Sci Rep ; 6: 26000, 2016 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-27193942

RESUMEN

Materials at high pressures and temperatures are of great current interest for warm dense matter physics, planetary sciences, and inertial fusion energy research. Shock-compression equation-of-state data and optical reflectivities of the fluid dense oxide, Gd3Ga5O12 (GGG), were measured at extremely high pressures up to 2.6 TPa (26 Mbar) generated by high-power laser irradiation and magnetically-driven hypervelocity impacts. Above 0.75 TPa, the GGG Hugoniot data approach/reach a universal linear line of fluid metals, and the optical reflectivity most likely reaches a constant value indicating that GGG undergoes a crossover from fluid semiconductor to poor metal with minimum metallic conductivity (MMC). These results suggest that most fluid compounds, e.g., strong planetary oxides, reach a common state on the universal Hugoniot of fluid metals (UHFM) with MMC at sufficiently extreme pressures and temperatures. The systematic behaviors of warm dense fluid would be useful benchmarks for developing theoretical equation-of-state and transport models in the warm dense matter regime in determining computational predictions.

15.
Artículo en Inglés | MEDLINE | ID: mdl-26382531

RESUMEN

Magnesium oxide has been experimentally and computationally investigated in the warm-dense solid and liquid ranges from 200 GPa to 1 TPa along the principal Hugoniot. The linear approximation between shock velocity and particle velocity is validated up to a shock velocity of 15 km/s from the experimental data, this suggesting that the MgO B1 structure is stable up to the corresponding shock pressure of ∼350 GPa. Moreover, our Hugoniot data, combined with ab initio simulations, show two crossovers between MgO Hugoniot and the extrapolation of the linear approximation line, occurring at a shock pressures of approximately 350 and 650 GPa, with shock temperatures of 8000 and 14,000 K, respectively. These crossover regions are consistent with the solid-solid (B1-B2) and the solid-liquid (B2-melt) phase boundaries predicted by the ab initio calculations.

16.
Artículo en Inglés | MEDLINE | ID: mdl-26764839

RESUMEN

Plastic materials (CH) doped with mid-Z elements are used as ablators in inertial confinement fusion (ICF) capsules and in their surrogates. Hugoniot equation of state (EOS) and electronic properties of CH doped with germanium (at 2.5% and 13% dopant fractions) are investigated experimentally up to 7 Mbar using velocity and reflectivity measurements of shock fronts on the GEKKO laser at Osaka University. Reflectivity and temperature measurements were updated using a quartz standard. Shocked quartz reflectivity was measured at 532 and 1064 nm. Theoretical investigation of shock pressure and reflectivity was then carried out by ab initio simulations using the quantum molecular dynamics (QMD) code abinit and compared with tabulated average atom EOS models. We find that shock states calculated by QMD are in better agreement with experimental data than EOS models because of a more accurate description of ionic structure. We finally discuss electronic properties by comparing reflectivity data to a semiconductor gap closure model and to QMD simulations.

17.
Bone ; 30(1): 185-90, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11792583

RESUMEN

The etiology of steroid-induced osteonecrosis (ON) is unclear. This study was designed to determine whether bone marrow fat cell size, intraosseous pressure, and blood flow rate differed between steroid-treated rabbits with ON and those without. Twenty-nine rabbits were intramuscularly injected once with 20 mg/kg of methylprednisolone acetate (MPSL), and five rabbits were injected once with physiologic saline (PS) as a control. Intraosseous pressure and blood flow rate in the proximal femur were determined before and at 2 weeks after the injection. After these measurements, both femora and humeri were histopathologically examined for the presence of ON, and size of bone marrow fat cells were morphologically examined. At 2 weeks after steroid injection, the intraosseous pressure was significantly higher in rabbits with ON than in those without (p = 0.0251), and the blood flow rate had decreased significantly more in rabbits with ON than in those without (p = 0.0051). The size of the bone marrow fat cells was significantly (p = 0.0004) larger in rabbits with ON (diameter, 63.5 +/- 5.8 microm) than in those without (diameter, 53.3 +/- 6.9 microm). Injection of PS (5 rabbits), 1 (10 rabbits), 5 (10 rabbits), and 20 (10 rabbits) mg/kg of body weight of MPSL showed that a larger dose of steroid increased both fat cell size and prevalence of ON. These results suggest that bone marrow fat cell enlargement and a rise in intraosseous pressure may be important when considering the pathophysiology of steroid-induced ON in rabbits.


Asunto(s)
Adipocitos/patología , Células de la Médula Ósea/patología , Metilprednisolona/análogos & derivados , Osteonecrosis/patología , Osteonecrosis/fisiopatología , Adipocitos/efectos de los fármacos , Animales , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Células de la Médula Ósea/efectos de los fármacos , Tamaño de la Célula/efectos de los fármacos , Modelos Animales de Enfermedad , Fémur/irrigación sanguínea , Fémur/efectos de los fármacos , Fémur/fisiopatología , Masculino , Metilprednisolona/toxicidad , Acetato de Metilprednisolona , Osteonecrosis/inducido químicamente , Presión , Conejos
18.
Bone ; 28(6): 641-9, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11425653

RESUMEN

We succeeded in developing a novel rabbit model of nonsteroid and nontraumatic osteonecrosis (ON) by use of a single- and low-dose lipopolysaccharide (LPS) injection. This model is simple and highly reproducible for the frequent development of multifocal and widespread ON lesions. Male adult Japanese white rabbits intravenously injected with a single injection of 10 microg/kg body weight of LPS were histopathologically examined in the early phase (3 [n = 3], 5 [n = 3], and 24 h [n = 3]) and at 4 weeks (n = 22). Seventy-seven percent of the rabbits developed multifocal ON 4 weeks after LPS injection. ON was also observed in the femoral and humeral condyle. The average percentage of necrotic area/total area examined was 86.7 +/- 29.1% and 78.8 +/- 16.7% in the proximal one third of both the femoral and humeral bones, respectively. Organized thrombi in the intraosseous small-sized arteries and arterioles were frequently seen in and around the necrotic tissues. In the early phase, LPS treatment prominently induced thrombocytopenia, hyperlipidemia, and increased plasma levels of plasminogen activator inhibitor-1 (PAI-1). The plasma level of PAI-1 was significantly higher in the rabbits with ON than in those without ON (p < 0.01). The immunohistochemical expression of tissue factor was exaggerated in monocytes/macrophages and adipocytes in both the femoral and humeral bones of the LPS-treated rabbits. Histologically, marrow necrosis and fibrin thrombi could be observed at 24 h. In addition, pretreatment with an anticoagulant, warfarin potassium, significantly decreased the incidence of LPS-induced ON (33%, n = 9, p < 0.05) associated with elongation of prothrombin time. The results of our study show that a single administration of low-dose lipopolysaccharide induces multifocal and widespread ON characterized by the pathophysiological participation of hypercoagulability in ON development. Therefore, this model would be useful for elucidating the pathogenesis of nonsteroid ON in humans especially inflammatory hypercoagulability-induced as well as for developing preventive and therapeutic strategies.


Asunto(s)
Lipopolisacáridos/toxicidad , Osteonecrosis/inducido químicamente , Animales , Peso Corporal , Relación Dosis-Respuesta a Droga , Fémur/patología , Inmunohistoquímica , Masculino , Osteonecrosis/patología , Conejos , Warfarina/farmacología
19.
Ann Epidemiol ; 7(7): 446-51, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9349911

RESUMEN

PURPOSE: We investigated familial aggregation as well as familial covariation of diseases by means of a questionnaire survey dealing with family histories of stomach cancer, stroke, hypertension, diabetes and tuberculosis as well as life style among 2,769 inhabitants of a rural community (84% of census population). METHODS: The strength of familial aggregation was shown by an odds ratio (OR) that compared the number of families in which siblings suffered from one of the above diseases among families in which at least one parent suffered from it, and among families in which neither did. Probands were divided into two groups for analysis: an under-55 "young group," and a 55-and-older "old group." RESULTS: The OR for stomach cancer was lowest and insignificant in the young group, and significant (2.2, p < 0.05) only in the old group. The OR for stroke, hypertension, and tuberculosis was 4.5-5.1 (p < 0.05) in the young group but decreased to 2.3-3.2 in the old group. Diabetes increased from 3.9 to 5.7 (p < 0.05) with advancing age. Age-related OR trends were not affected by exposure to cigarette smoke in the past. Stomach cancer showed a borderline familial covariation with diabetes and a borderline inverse covariation with hypertension. Hypertension showed a familial covariation with stroke and diabetes. CONCLUSIONS: Among the investigated diseases, familial aggregation was weakest for stomach cancer. The results suggest that stomach cancer may share a common familial etiologic factor with diabetes and hypotension.


Asunto(s)
Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/genética , Adulto , Distribución por Edad , Anciano , Trastornos Cerebrovasculares/complicaciones , Trastornos Cerebrovasculares/epidemiología , Estudios de Cohortes , Comorbilidad , Intervalos de Confianza , Complicaciones de la Diabetes , Diabetes Mellitus/epidemiología , Susceptibilidad a Enfermedades , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/epidemiología , Incidencia , Japón/epidemiología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Linaje , Factores de Riesgo , Población Rural , Distribución por Sexo , Encuestas y Cuestionarios
20.
Eur J Gastroenterol Hepatol ; 13(1): 75-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11204816

RESUMEN

We describe a patient with autosomal dominant polycystic kidney disease who was successfully managed for severe abdominal distension, impaired liver function and a portosystemic shunt by interventional therapies. The patient's intra-hepatic portal vein was compressed and narrowed by multiple liver cysts, which resulted in a decrease of the portal blood flow and portal hypertension due to a huge gastro-renal shunt These haemodynamic changes were assumed to contribute to insufficient protein synthesis in the liver. Therefore, we first repeatedly performed minocycline hydrochloride instillations to treat the multiple liver cysts. Then, we conducted a partial splenic embolization to prevent elevation of the portal vein pressure prior to balloon-occluded retrograde transvenous obliteration which was performed to increase the portal blood flow. The portal blood flow markedly increased, and protein synthesis in the liver also recovered and the clinical symptoms improved. The patient has been monitored for more than two years up to the present and her liver function parameters have remained within the normal range. Renal insufficiency is known to be a major prognostic factor in autosomal dominant polycystic kidney disease. In some cases, however, liver involvement with multiple cysts may result in a fatal outcome. In such cases, interventional therapies, as provided to this patient, should be considered.


Asunto(s)
Quistes/complicaciones , Embolización Terapéutica , Hepatopatías/complicaciones , Riñón Poliquístico Autosómico Dominante/complicaciones , Riñón Poliquístico Autosómico Dominante/cirugía , Quistes/terapia , Drenaje , Femenino , Humanos , Hipertensión Portal/etiología , Hígado/metabolismo , Hepatopatías/terapia , Fallo Hepático/etiología , Persona de Mediana Edad , Riñón Poliquístico Autosómico Dominante/fisiopatología , Sistema Porta/fisiología , Pronóstico , Tomografía Computarizada por Rayos X
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