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1.
Osteoarthritis Cartilage ; 31(5): 576-587, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36528308

RESUMEN

OBJECTIVE: The Anterior Cruciate Ligament (ACL)-deficient model helps to clarify the mechanism of knee osteoarthritis (OA); however, the conventional ACL injury model could have included concurrent onset factors such as direct compression stress to cartilage and subchondral bone. In this study, we established a novel Non-invasive ACL-Ruptured mouse model without concurrent injuries and elucidated the relationship between OA progression and joint instability. DESIGN: We induced the ACL-Rupture non-invasively in twelve-week-old C57BL/6 male mice and evaluated histological, macroscopical, and morphological analysis at 0 days. Next, we created the ACL-R, controlled abnormal tibial translation (CATT), and Sham groups. Then, the joint stability and OA pathophysiology were analyzed at 2, 4, and 8 weeks. RESULTS: No intra-articular injuries, except for ACL rupture, were observed in the ACL-R model. ACL-R mice increased anterior tibial displacement compared to the Sham group (P < 0.001, 95% CI [-1.509 to -0.966]) and CATT group (P < 0.001, 95% CI [-0.841 to -0.298]) at 8 weeks. All mice in the ACL-R group caused cartilage degeneration. The degree of cartilage degeneration in the ACL-R group was higher than in the CATT group (P = 0.006) at 8 weeks. The MMP-3-positive cell rate of chondrocytes increased in the ACL-R group than CATT group from 4 weeks (P = 0.043; 95% CI [-28.32 to -0.364]) while that of synovial cells increased at 8 weeks (P = 0.031; 95% CI [-23.398 to -1.021]). CONCLUSION: We successfully established a Non-invasive ACL-R model without intra-articular damage. Our model revealed that chondrocytes might react to abnormal mechanical stress prior to synovial cells while the knee OA onset.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Inestabilidad de la Articulación , Osteoartritis de la Rodilla , Masculino , Animales , Ratones , Ratones Endogámicos C57BL , Condrocitos , Ligamento Cruzado Anterior , Lesiones del Ligamento Cruzado Anterior/complicaciones , Modelos Animales de Enfermedad
2.
Osteoarthritis Cartilage ; 30(3): 451-460, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34906679

RESUMEN

OBJECTIVE: It has been debated whether the onset of knee osteoarthritis is initiated in cartilage or subchondral bone. The purpose of this study was to clarify the effects of increasing or decreasing joint instability on cartilage degeneration and subchondral bone changes in knee OA by comparing different models of joint instability. DESIGN: We used the anterior cruciate ligament transection (ACL-T) model and the destabilization of the medial meniscus (DMM) model. In addition, we created a controlled abnormal tibial translation (CATT) model and a controlled abnormal tibial rotation (CATR) model. We performed joint instability analysis, micro-computed tomography analysis, histological and immunohistological analysis in 4 and 6 weeks. RESULTS: The CATT group suppressed joint instability in the ACL-T group (6 weeks; P = 0.032), and the CATR group suppressed joint instability in the DMM group (6 weeks; P = 0.032). Chondrocyte hypertrophy in the ACL-T and DMM groups was increased compared to the Sham group (6 weeks; [ACL-T vs Sham], P = 0.002, 95%CI [5.983-33.025]; [DMM vs Sham], P = 0.022, 95%CI [1.691-28.733]). In the subchondral bone, the BV/TV in the DMM and CATR groups was increased compared to the ACL-T and CATT groups (6 weeks; [DMM vs ACL-T], P = 0.002, 95%CI [7.404-37.582]; [DMM vs CATT], P = 0.014, 95%CI [2.881-33.059]; [CATR vs ACL-T], P = 0.006, 95%CI [4.615-34.793]; [CATR vs CATT], P = 0.048, 95%CI [0.092-30.270]). CONCLUSIONS: This study showed that joint instability promotes chondrocyte hypertrophy, but subchondral bone changes were influenced by differences in ACL and meniscus function.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior/complicaciones , Enfermedades de los Cartílagos/etiología , Inestabilidad de la Articulación/complicaciones , Osteoartritis de la Rodilla/etiología , Lesiones de Menisco Tibial/complicaciones , Animales , Condrocitos/patología , Modelos Animales de Enfermedad , Masculino , Ratones
3.
Colorectal Dis ; 20(7): O162-O172, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29752849

RESUMEN

AIM: Clinical guidelines recommend adjuvant chemotherapy for high-risk patients with Stage II-III colorectal cancer. However, chemotherapeutic administration rates differ significantly between hospitals. We assessed the prognostic benefit of adjuvant chemotherapy in patients with Stage IIb/c colorectal cancer, and the prognostic impact of interhospital variations in the administration of adjuvant chemotherapy for Stage II-III colorectal cancer. METHOD: We conducted a multicentre, retrospective study of 17 757 patients with Stage II-III colorectal cancer treated between 1997 and 2008 in 23 hospitals in Japan. Hospitals were classified as high-rate (rate > 42.8%) or low-rate (rate ≤ 42.8%), chemotherapy prescribing clinics. RESULTS: The 5-year overall survival (OS) of patients with Stage II-III colorectal cancer receiving adjuvant chemotherapy was significantly higher than for those not receiving adjuvant chemotherapy (85.7% vs 79.2%, P < 0.01 and 79.9% vs 72.5%, P < 0.01, respectively). For patients with Stage II disease, adjuvant chemotherapy was an independent factor for longer OS (P < 0.01, hazard ratio = 0.71). Both adjuvant chemotherapy and high-rate hospital independently improved OS for patients with Stage III colorectal cancer (both P < 0.01; hazard ratio = 0.68 and 0.87, respectively). CONCLUSION: Significant prognostic benefit was found for patients with Stage IIb/c colorectal cancer who received adjuvant chemotherapy, with patients who were treated in hospitals with high adjuvant chemotherapy rates demonstrating better prognoses.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/mortalidad , Hospitales/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante/mortalidad , Neoplasias Colorrectales/patología , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Adulto Joven
5.
J Dairy Sci ; 98(3): 1593-603, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25529420

RESUMEN

Lactobacillus gasseri is a widespread commensal lactic acid bacterium inhabiting human mucosal niches and has many beneficial effects as a probiotic. However, L. gasseri is difficult to grow in milk, which hurts usability for the food industry. It had been previously reported that supplementation with yeast extract or proteose peptone, including peptides, enables L. gasseri to grow well in milk. In this study, our objective was to confirm peptide requirement of L. gasseri and evaluate efficacy of peptide release by enzymatic proteolysis on growth of L. gassei in milk. Three strains of L. gasseri did not grow well in modified DeMan, Rogosa, Sharpe broth without any nitrogen sources (MRS-N), but addition of a casein-derived peptide mixture, tryptone, promoted growth. In contrast, little effect was observed after adding casein or a casein-derived amino acid mixture, casamino acids. These results indicate that L. gasseri requires peptides, not proteins or free amino acids, among milk-derived nitrogen sources for growth. Lactobacillus gasseri JCM 1131T hardly had growth capacity in 6 kinds of milk-based media: bovine milk, human milk, skim milk, cheese whey, modified MRS-N (MRSL-N) supplemented with acid whey, and MRSL-N supplemented with casein. Moreover, treatment with digestive proteases, particularly pepsin, to release peptides made it grow well in each milk-based medium. The pepsin treatment was the most effective for growth of strain JCM 1131T in skim milk among the tested food-grade proteases such as trypsin, α-chymotrypsin, calf rennet, ficin, bromelain, and papain. As well as strain JCM 1131T, pepsinolysis of milk improved growth of other L. gasseri strains and some strains of enteric lactobacilli such as Lactobacillus crispatus, Lactobacillus gallinarum, Lactobacillus johnsonii, and Lactobacillus reuteri. These results suggest that some relatives of L. gasseri also use peptides as desirable nitrogen sources, and that milk may be a good supplier of nutritious peptides to enteric lactobacilli including L. gasseri after peptic digestion in the gastrointestinal tract. This is the first report showing peptide requirement of L. gasseri and efficacy of pepsinolysis on the growth of L. gasseri and its relatives in milk. This study would contribute to increasing usability of L. gasseri and its relatives as probiotics in dairy foods.


Asunto(s)
Lactobacillus/crecimiento & desarrollo , Leche/microbiología , Péptidos/metabolismo , Aminoácidos/metabolismo , Animales , Caseínas/metabolismo , Bovinos , Quimotripsina/metabolismo , Tracto Gastrointestinal/microbiología , Leche/química , Nitrógeno/química , Pepsina A/metabolismo , Fragmentos de Péptidos/metabolismo , Péptido Hidrolasas/metabolismo , Probióticos/metabolismo
6.
Br J Cancer ; 107(4): 632-8, 2012 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-22805328

RESUMEN

BACKGROUND: The expression of L-type amino-acid transporter 1 (LAT1) is tumour-specific and has been shown to have essential roles in cell growth and survival. However, little is known regarding the clinical significance of LAT1 expression in pancreatic cancer. This study was conducted to determine the prognostic significance of LAT1 expression. METHODS: A total of 97 consecutive patients with surgically resected pathological stage I-IV pancreatic ductal adenocarcinoma were retrospectively reviewed. Tumour sections were stained by immunohistochemistry for LAT1, CD98, Ki-67 and vascular endothelial growth factor (VEGF), and microvessel density was determined by CD34 and p53. RESULTS: L-type amino-acid transporter 1 and CD98 were highly expressed in 52.6% (51/97) and 56.7% (55/97) of cases, respectively (P=0.568). The expression of LAT1 within pancreatic cancer cells was significantly associated with disease stage, tumour size, Ki-67, VEGF, CD34, p53 and CD98. L-type amino-acid transporter 1 expression was confirmed to be a significant prognostic factor for predicting poor outcome by multivariate analysis. CONCLUSION: L-type amino-acid transporter 1 expression is a promising pathological marker for the prediction of outcome in patients with pancreatic cancer.


Asunto(s)
Carcinoma Ductal Pancreático/metabolismo , Transportador de Aminoácidos Neutros Grandes 1/metabolismo , Neoplasias Pancreáticas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/cirugía , Supervivencia sin Enfermedad , Femenino , Proteína-1 Reguladora de Fusión/metabolismo , Humanos , Inmunohistoquímica , Masculino , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico
7.
Nanotechnology ; 21(28): 285304, 2010 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-20562484

RESUMEN

One-dimensional tungsten nanowires and two-dimensional tungsten nanowire networks were fabricated on a tungsten substrate by using electron-beam-induced deposition (EBID) without precursor injection. The as-prepared tungsten nanostructures were studied using a combination of energy-dispersive x-ray spectroscopy and selected area electron diffraction. It was revealed that the tungsten nanostructures were composed of pure metallic tungsten. The WO(3) oxide formed in the chemical preparation of tungsten foils was probably the source of tungsten for the fabrication of tungsten nanostructures by EBID.

8.
Int J Immunopathol Pharmacol ; 23(1): 1-11, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20377990

RESUMEN

To prevent and control disease caused by exposure to various agents, it is necessary to determine the harmful level of intervention and to establish a method for measuring that level. In-air microparticle-induced X-ray emission (in-air micro-PIXE) analysis is based on irradiation of specimens with a proton ion microbeam, and has been modified for biological application. Two-dimensional analysis and quantitative analysis using the system confirmed that asbestos induced apoptosis by upregulating Fas expression and also revealed the accumulation of CD163-expressing macrophages in the lungs of patients with asbestosis. By quantitative comparison of the area of Fas or CD163 expression and the Fas- or CD163-negative area in asbestos lung tissue, the harmful levels which caused the expression of Fas or CD163 could be estimated on Silica, Ferrous iron, and Magnesium (the components of asbestos) deposition. These results indicate that the system could be useful for investigating the pathogenesis of inhaled particle-induced immune reactions and for determining harmful levels of exogenous agents.


Asunto(s)
Antígenos CD/análisis , Antígenos de Diferenciación Mielomonocítica/análisis , Amianto/análisis , Asbestosis/inmunología , Pulmón/química , Receptores de Superficie Celular/análisis , Espectrometría por Rayos X/métodos , Receptor fas/análisis , Anciano , Asbestosis/metabolismo , Asbestosis/patología , Humanos , Inmunohistoquímica , Masculino
9.
Lett Appl Microbiol ; 50(4): 406-11, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20156306

RESUMEN

AIM: The study aimed for the complete purification and recharacterization of the highly hydrophobic circular bacteriocins, gassericin A and reutericin 6. METHODS AND RESULTS: Gassericin A and reutericin 6 were purified to homogeneity using previously described method and reverse-phase HPLC with an octyl column and eluents of aqueous acetonitrile and 2-propanol. Mass analysis, N-terminal sequencing and bacteriocin assay of the HPLC-purified bacteriocins showed the two bacteriocins had identical seamless circular structures with the same m/z value (5651) of [M + H](+) and both had the same specific activity. D/L-amino acid composition analysis using two distinct methods with the chiral fluorescent derivatization reagents (+)-1-(9-fluorenyl)ethyl chloroformate and O-phthalaldehyde/N-acetyl-L-cystein revealed neither gassericin A nor reutericin 6 contained D-alanine residues contrary to our previous results. CONCLUSION: Purified gassericin A and reutericin 6 are chemically identical circular molecules containing no D-alanine residues. SIGNIFICANCE AND IMPACT OF THE STUDY: The HPLC conditions developed in this study will facilitate advanced purification and correct characterization of other highly hydrophobic bacteriocins.


Asunto(s)
Bacteriocinas/química , Bacteriocinas/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Lactobacillus/química , Espectrometría de Masas
10.
J Dairy Sci ; 92(6): 2365-72, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19447968

RESUMEN

Lactobacillus gasseri LA39 and LA158 isolated from human-infant feces produce bacteriocins named gassericins A and T, respectively. Both gassericins have high heat stability (121 degrees C, 10 min), good pH tolerance (pH 2-11), and strong bactericidality against many gram-positive bacteria, especially lactic acid bacteria, and thus are expected to be effective food preservatives. A microwell plate assay against 12 strains of custard cream spoilage bacteria showed that the gassericins had broader antibacterial spectra than nisin A. Although the gassericins allowed gram-negative isolates to grow, they successfully inhibited the growth of all tested bacterial strains in microwells with the addition of glycine. Glycine was bacteriostatic against many strains except lactic acid bacteria. For practical use, gassericin A was efficiently produced by cultivation in a food-grade medium improved using cheese whey, nourishing proteose peptone, and surfactant yolk lecithin. The practical preservative effect of gassericin A and glycine was verified from the viability of 4 isolated strains, Bacillus cereus, Lactococcus lactis ssp. lactis, Achromobacter denitrificans, and Pseudomonas fluorescens, in custard creams. Custard cream containing 123 arbitrary units of gassericin A per milliliter entirely growth-inhibited the 2 gram-positive strains. In custard cream containing an insufficient amount of gassericin A (49 arbitrary units/mL), the gram-positive strains gradually grew but were completely inhibited by the addition of 0.5% (wt/wt) glycine. The 2 gram-negative strains did not multiply even in the additive-free custard cream, probably because of the unsuitable growth environment. This is the first report showing the combined effect of bacteriocin and glycine and their application for food preservation, which may be helpful for future use in the food industry.


Asunto(s)
Antibiosis , Bacteriocinas , Productos Lácteos , Conservación de Alimentos , Glicina , Lactobacillus/química , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Bacteriocinas/farmacología , Productos Lácteos/análisis , Productos Lácteos/microbiología , Productos Lácteos/normas , Microbiología de Alimentos , Conservación de Alimentos/métodos , Conservación de Alimentos/normas , Glicina/farmacología , Acetato de Sodio/farmacología
11.
Int J Immunopathol Pharmacol ; 21(3): 567-76, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18831923

RESUMEN

Inhalation of asbestos increases the risk of lung cancer and pulmonary fibrosis. It is difficult to directly assess the distribution and content of inhaled particles in lung tissue sections. The purpose of this study is to employ an in-air micro particle induced X-ray emission (in-air micro-PIXE) system for assessment of the spatial distribution and content of asbestos and other metals in lung tissue. A proton ion-microbeam from this system was applied to irradiate lung tissue of patients with or without asbestosis, tumor tissue from both groups, and asbestos fibers (in vitro). The content of each element composing asbestos and those of other metals were calculated and their distribution was assessed from the characteristic X-ray pattern for each element obtained after irradiation. This in-air micro-PIXE system could identify the location of asbestos bodies composed of Si, Mg, and Fe in lung tissue sections. Macrophage and lymphocytes accumulated in that area. This new system also revealed deposits of titanium, nickel, and cobalt in the lung tissues, in addition to asbestos bodies. The Si and Fe content were higher in lungs with asbestosis than in lungs without asbestosis or in tumor tissue. Analysis of asbestos fibers composed of chrysotile, crocidolite, and amosite showed that the ratios of Si, Fe, and Mg corresponded with those for the chemical structures. In-air micro-PIXE analysis is useful for assessing the distribution and quantities of asbestos bodies and also other metals in lung tissue comparing to immune-related cell localizations, and is also useful for analysis of standard asbestos fibers.


Asunto(s)
Amianto/análisis , Pulmón/química , Metales/análisis , Espectrometría por Rayos X/métodos , Anciano , Humanos , Masculino
12.
J Dairy Sci ; 91(8): 2938-46, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18650270

RESUMEN

Custard cream is made from highly nutritive raw materials such as milk and sugar and is easily spoiled by the multiplication of specific microbial contaminants or residents. However, this spoilage microbial community has not been studied. We determined the spoilage microbiota in commercial custard creams using culture-dependent and independent methods. Using the culture-dependent analysis with various agar media, 185 bacterial colonies and 43 eukaryal colonies were isolated from 7 commercial custard cream products. All bacterial isolates were morphologically, physiologically, and genetically identified as bacilli, staphylococci, lactic acid bacteria, and psychrotrophic gram-negative rods. Using culture-independent molecular analysis, the PCR-denaturing gradient gel electrophoresis technique, spoilage of the commercial custard creams was found to be caused by bacilli, staphylococci, lactic acid bacteria, psychrotrophic gram-negative rods, Anoxybacillus sp., Caurobacter sp., and Streptococcus sp. bacteria. The detected spoilage bacteria were the same species as previously detected in spoiled milk products and shown in other reports, suggesting that spoilage bacteria in a raw material easily grow in processed foods made from milk. We determined the spoilage microbial communities in commercial custard creams, and these are the first data concerning spoilage microbiota in nonfermented processed foods using a culture-independent analysis. Our study will be useful for the manufacture and safe preservation of dairy products because the first step toward safe food preservation by food manufacturers is to understand the spoilage microbiota in a target food to select optimal preservatives and to reduce the use of food additives.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Productos Lácteos/microbiología , Microbiología de Alimentos , Bacterias/genética , Bacterias/crecimiento & desarrollo , Fenómenos Fisiológicos Bacterianos , Técnicas de Tipificación Bacteriana , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Especificidad de la Especie
13.
Biol Trace Elem Res ; 124(1): 60-9, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18473126

RESUMEN

This study was undertaken to elucidate the intracellular changes of metal elements after the administration of fucoidan extracted from Cladosiphon okamuranus. TRL1215 cells (normal rat liver cell line) were treated with 0, 0.1, or 1.0 mg/ml fucoidan and incubated in 5% CO2 at 37 degrees C. The cellular levels of Mg, Al, Fe, and Zn were significantly increased in the 1.0 mg/ml fucoidan-treated cells compared to those of the 0.1 mg/ml fucoidan-treated cells and the control. Next, TRL1215 cells were cultured on Mylar film overnight. At 24 h after 5-bromo-2'-deoxyuridine dosing, 0, 0.1, or 1.0 mg/ml fucoidan was treated for 9 h. The cellular distribution of elements was analyzed using in-air micro-micro-particle induced X-ray emission. The X-ray spectra showed that yields of Al, Mg, and Zn were high in order of the 1.0 mg/ml fucoidan-treated sample, the 0.1 mg/ml fucoidan-treated sample, and the control. Fe yield was mildly increased by fucoidan administration. In fucoidan-treated cells, the focal accumulation of Br was correlated spatially with phosphorous-rich region, suggesting that Br was localized within the nucleus. Al distribution provided a spatial association with Br map. These data suggest that fucoidan increases the accumulations of Al, Mg, Fe, and Zn in normal rat hepatocytes, and fucoidan-binding Al is postulated to be transferred into the nucleus.


Asunto(s)
Metales/metabolismo , Phaeophyceae/química , Polisacáridos/farmacología , Algas Marinas/química , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Medios de Cultivo , Inmunohistoquímica , Ratas , Análisis Espectral
14.
Biol Trace Elem Res ; 117(1-3): 115-26, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17873397

RESUMEN

This study undertook the analysis of tissue cadmium (Cd) distribution using in-air micro-particle-induced X-ray emission (PIXE) and the examination of the involvement of metal ions in parenteral Cd toxicity. A mouse was injected intraperitoneally with 3 mg/kg body weight of CdCl2 thrice weekly. After 27 wk, the liver and kidney were excised and fixed in 10% formalin solution for 4 h and then embedded in paraffin. Thin paraffin sections were used to analyze trace elements with in-air micro-PIXE and to examine metallothionein protein and histological changes. Cd distribution was determined by micro-PIXE in the liver and renal cortex of the Cd-exposed mouse, and the net Cd count was higher in the liver than in the renal cortex. The net iron (Fe) count was higher in the liver of the Cd-exposed mouse compared to the control, and an opposite tendency was observed in the renal cortex. Wide cellular Cd distribution was demonstrated in the liver and renal cortex of the chronic Cd-exposed mouse compared to the control. Metallothionein staining was increased by chronic exposure to Cd both in the liver and kidney, and nephrotoxicity was more apparent than hepatotoxicity. The modification of tissue Fe and calcium distribution by an intraperitoneal injection of Cd might be involved in Cd-induced toxicity.


Asunto(s)
Cadmio/análisis , Cadmio/metabolismo , Corteza Renal/metabolismo , Hígado/metabolismo , Animales , Cadmio/efectos adversos , Esquema de Medicación , Femenino , Corteza Renal/patología , Hígado/patología , Ratones , Ratones Endogámicos ICR , Espectrometría por Rayos X , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiología
15.
Sci Rep ; 6: 26099, 2016 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-27185352

RESUMEN

The dynamic behaviour of atomic-size disarrangements of atoms-point defects (self-interstitial atoms (SIAs) and vacancies)-often governs the macroscopic properties of crystalline materials. However, the dynamics of SIAs have not been fully uncovered because of their rapid migration. Using a combination of high-voltage transmission electron microscopy and exhaustive kinetic Monte Carlo simulations, we determine the dynamics of the rapidly migrating SIAs from the formation process of the nanoscale SIA clusters in tungsten as a typical body-centred cubic (BCC) structure metal under the constant-rate production of both types of point defects with high-energy electron irradiation, which must reflect the dynamics of individual SIAs. We reveal that the migration dimension of SIAs is not three-dimensional (3D) but one-dimensional (1D). This result overturns the long-standing and well-accepted view of SIAs in BCC metals and supports recent results obtained by ab-initio simulations. The SIA dynamics clarified here will be one of the key factors to accurately predict the lifetimes of nuclear fission and fusion materials.

16.
Biochim Biophys Acta ; 963(1): 98-108, 1988 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-2460142

RESUMEN

Proline-rich protein (PRP) is a plasma protein associated with lipoproteins. In an attempt to clarify the biological significance of this protein, we isolated and characterized it and studied the biological role in plasma. PRP was isolated by immunosorber column chromatography and by gel filtration and ion-exchange chromatography. The molecular weight determined by gel filtration chromatography was 352,000, that is, about 5-times larger than the weight determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (73,800), indicating pentamer formation. About 10 or 11 isoproteins (pI 5.89-6.55) were observed by isoelectric focusing gel electrophoresis. PRP contained fucose, mannose, galactose, glucosamine and sialic acid accounting for 8.0% of the dry weight. PRP also had a hydrophilic property, as determined by charge shift electrophoresis. Levels of this protein in the human serum related to triacylglycerol-rich lipoproteins. The concentration of PRP correlated to the erythrocyte sedimentation rate (ESR), the C-reactive protein (CRP) and alpha 1- and alpha 2-globulin. Sera from patients with infection and inflammation showed significantly higher PRP levels than those noted in controls. Levels of PRP rose in parallel with ESR and CRP levels following acute myocardial infarction, and the maximal level was noted on the 7th postinfarction day. The PRP levels were elevated during the active phase of pneumonia, followed normalization. These data suggest that PRP is an acute phase reactant and may be important in the metabolism of triacylglycerol-rich lipoproteins.


Asunto(s)
Proteínas de Fase Aguda/análisis , Glicoproteínas/análisis , Péptidos/análisis , Aminoácidos/análisis , Electroforesis en Gel de Poliacrilamida , Humanos , Inmunodifusión , Inmunoelectroforesis , Estudios Longitudinales , Masculino , Peso Molecular , Dominios Proteicos Ricos en Prolina
17.
Biochim Biophys Acta ; 1043(2): 169-76, 1990 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-2107878

RESUMEN

A novel genetic variant of apolipoprotein(apo) A-I Fukuoka, has been identified in a Japanese family. This variant has a relative charge of +2 compared to normal apolipoprotein A-I (A-I4), on the isoelectric focusing gels and the same molecular mass and immunologic characteristics as normal apolipoprotein A-I. This variant, transmitted as an autosomal co-dominant inheritance was purified by preparative Immobiline isoelectric focusing. Sequence analysis after cleavage with lysyl endopeptidase and CNBr, followed by high-performance liquid chromatography revealed a single substitution of lysine at position 110, instead of the usual glutamic acid. This mutant apolipoprotein A-I has much the same potential as to activate lecithin-cholesterol acyltransferase.


Asunto(s)
Apolipoproteínas A/sangre , Variación Genética , Errores Innatos del Metabolismo Lipídico/diagnóstico , Lipoproteínas HDL/sangre , Secuencia de Aminoácidos , Apolipoproteína A-I , Secuencia de Bases , Humanos , Focalización Isoeléctrica , Errores Innatos del Metabolismo Lipídico/genética , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Linaje , Fosfatidilcolinas/aislamiento & purificación , Esterol O-Aciltransferasa/aislamiento & purificación
18.
Biochim Biophys Acta ; 1174(3): 279-81, 1993 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-8104035

RESUMEN

In a population of Japanese subjects, we surveyed codon 347 of the apolipoprotein (apo) A-IV gene and found that the frequency of a rare allele at this point was extremely low compared to that in western populations. Only one of 850 unrelated samples showed mutation at the enzyme recognition site by agarose gel electrophoresis. However, direct sequencing of the coding region revealed that it did not result from the ACT (Thr) to TCT (Ser) mutation which has been reported in western countries, but from an ACT to ACG (Thr) mutation, which does not affect the primary structure of apo A-IV. Two additional family members showed the same point mutation at codon 347.


Asunto(s)
Apolipoproteínas A/genética , Codón , Adulto , Anciano , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Mutación , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción
19.
Biochim Biophys Acta ; 1166(1): 131-4, 1993 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-8431487

RESUMEN

We describe a method for the rapid and non-radioactive examination of DNA samples for a mutation of cholesteryl ester transfer protein using a polymerase chain reaction-mediated site-directed mutagenesis. CETP deficiencies were studied in 554 Japanese subjects (370 men, 184 women) aged between 18 and 91 (mean 48.3 years). By this method, we detected one homozygote and 3 heterozygotes of the CETP deficiency.


Asunto(s)
Proteínas Portadoras/genética , Glicoproteínas , Mutagénesis Sitio-Dirigida , Mutación Puntual , Adulto , Anciano , Anciano de 80 o más Años , Apolipoproteínas/sangre , Apolipoproteínas/genética , Secuencia de Bases , Proteínas Portadoras/química , Proteínas de Transferencia de Ésteres de Colesterol , Ésteres del Colesterol/metabolismo , ADN/aislamiento & purificación , Femenino , Humanos , Hiperlipoproteinemias/sangre , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa
20.
Biochim Biophys Acta ; 1128(1): 58-64, 1992 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-1356443

RESUMEN

During the screening of samples obtained from 5 individuals with type III hyperlipidemia, we identified a variant of apolipoprotein (apo) E which exhibited a discrepancy in apo E phenotype showing the E3/E1 isoform on isoelectric focusing (IEF) analysis and E3/E3 on gene analysis. Sequence analysis of the DNA of the proband that was amplified by PCR and subcloned, revealed a single substitution of one lysine (AAG) for one glutamic acid (GAG) at position 146, thereby adding two negatively charged units to apo E3. This defect had been described only for apo E1 to date (Mann et al. (1989) Clin. Res. 37, 520A (abstract)). In this case, PCR-mediated site-directed mutagenesis was used to identify the structural alterations forming the abnormal E1 genotype in the proband's family. Purified apo E1 Lys-146----Glu showed less than 10% of binding activity to apo B, E receptor on human skin fibroblasts compared with apo E3. This substitution demonstrates that Lys-146 is essential for the binding of apo E to the receptor.


Asunto(s)
Apolipoproteínas E/genética , ADN/sangre , Hiperlipoproteinemia Tipo III/sangre , Hiperlipoproteinemia Tipo III/genética , Polimorfismo de Longitud del Fragmento de Restricción , Adulto , Secuencia de Aminoácidos , Apolipoproteína E2 , Apolipoproteínas E/sangre , Apolipoproteínas E/aislamiento & purificación , Secuencia de Bases , Niño , ADN/genética , ADN/aislamiento & purificación , Electroforesis en Gel Bidimensional , Femenino , Tamización de Portadores Genéticos , Glutamatos , Ácido Glutámico , Humanos , Lisina , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Linaje , Reacción en Cadena de la Polimerasa/métodos
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