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1.
Langmuir ; 36(40): 11957-11962, 2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-32933247

RESUMEN

Water-soluble polymers such as poly(acrylic acid) (PAA) are widely applied in dispersants, thickeners, flocculants, and superabsorbent polymers. Here, submicrometer-sized monodisperse PAA particles were successfully prepared by precipitation polymerization in acetonitrile at 55 °C with 2,2'-azobis(2,4-dimethylvaleronitrile) as an initiator. In a medium with a high dielectric constant, the particles were stabilized by electrostatic repulsion without a colloidal stabilizer during the polymerization. Moreover, the obtained PAA particles were spontaneously cross-linked in the absence of a cross-linker. The degree of the cross-linking was strongly dependent on the amount of water (500-10,000 ppm) in the polymerization medium. The PAA particles swelled more with acrylic acid with an increase in the amount of water. Thus, in the case of high water content, the particles would become the main polymerization loci, which in turn results in the cross-linking structures owing to the α-hydrogen abstraction of PAA chains during the polymerization.

2.
Macromol Rapid Commun ; 41(14): e2000271, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32548946

RESUMEN

Micrometer-sized poly(ionic liquid) (PIL) particles with an anionic side chain, poly(1-butyl-3-methylimidazolium 3-sulfopropyl methacrylate) (poly([Bmim][SPMT])), are successfully prepared by dispersion polymerization at 60 °C in ethanol/ethyl acetate (2/8, w/w) with poly(vinylpyrrolidone) as a stabilizer. However, the obtained particles do not maintain the particulate state during drying at room temperature due to poly([Bmim][SPMT])'s low glass-transition temperature, below room temperature. In order to prevent coalescence and maintain particle shape, a cross-linking monomer is added after the nucleation stage of dispersion polymerization. Moreover, Fourier-transform infrared spectroscopy (FT-IR) demonstrates cation exchange between the obtained particles and metal cations (Ag+ ).


Asunto(s)
Líquidos Iónicos , Aniones , Cationes , Polimerizacion , Espectroscopía Infrarroja por Transformada de Fourier
3.
Environ Monit Assess ; 192(7): 467, 2020 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-32601932

RESUMEN

To evaluate the seasonal water circulation of Tonle Sap Lake and its tributary rivers in Cambodia, the spatial distribution patterns of major and trace elements in surface water were investigated. Based on the similarity of the dissolved elemental concentrations, the water samples were mainly divided into the three groups: samples with relatively high percentages of Ca, Mo, and Sb (Subcluster B1); samples with high Si, Al, and Fe (B2); and samples with high Na, K, and Mg (B3). During the rainy season, the elemental composition of lake water (B1) appeared to be greatly influenced by the intrusion of water from the Mekong River (B1) through the Tonle Sap River (B1). During the dry season, the type of lake water shifted to B3, suggesting that the lake water stored during the rainy season was replaced by inflow from other tributaries and groundwater in its vicinity. Thus, the seasonal changes in the elemental composition of the lake water were largely controlled by surface water and groundwater circulation. The dissolved As concentration was higher in the lake water and during the dry season than that in the river water and during the rainy season, indicating the discharge of As from the lake's bottom sediment during the dry season. Although the redox cycling of Fe and Mn appeared to be less important due to the shallow water depth in the lake, there are potential risks of As poisoning induced by the formation of an anoxic water mass and increment in the concentration of phosphorus if eutrophication continues to progress.


Asunto(s)
Oligoelementos , Contaminantes Químicos del Agua/análisis , Cambodia , Monitoreo del Ambiente , Lagos , Ríos , Agua
4.
Artículo en Inglés | MEDLINE | ID: mdl-27302069

RESUMEN

The ratios of stable isotopes of certain elements in rocks and minerals have strong regional characteristics that are reflected in atmospheric components, in water, and in the living organisms that form Earth's surface environment as well as in agricultural and fishery products. Geologically derived stable isotope ratios can be used as a tracer for the source of many kinds of substances, with current geochemical techniques allowing the precise determination of numerous stable isotope ratios in both natural and manmade objects. This review presents examples of the use of stable isotopes as tracers within diverse dynamic ecosystems, focusing on Sr isotopes but also including examples of Nd and Pb isotopic analysis, and reviewing the potential of this technique for a wide range of environmental research, including determining the geographic origin of food and archeological materials.


Asunto(s)
Monitoreo del Ambiente/métodos , Geología , Plomo/química , Neodimio/química , Isótopos de Estroncio/química , Ecosistema , Humanos , Isótopos
5.
Am J Phys Anthropol ; 158(2): 300-311, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26279451

RESUMEN

OBJECTIVE: Archaeological remains strongly suggest that the Holocene Japanese hunter-gatherers, the Jomon people, utilized terrestrial plants as their primary food source. However, carbon and nitrogen isotope analysis of bone collagen indicates that they primarily exploited marine resources. We hypothesize that this inconsistency stems from the route of protein synthesis and the different proportions of protein-derived carbon in tooth enamel versus bone collagen. Carbon isotope ratios from bone collagen reflect that of dietary protein and may provide a biased signal of diet, whereas isotope ratios from tooth enamel reflect the integrated diet from all macronutrients (carbohydrates, lipids, and proteins). METHODS: In order to evaluate the differences in inferred diet between the archaeological evidence and bone collagen isotope data, this study investigated carbon isotopes in Jomon tooth enamel from four coastal sites of the Middle to Late-Final Jomon period (5,000-2,300 years BP). RESULTS: Carbon isotope ratios of human teeth are as depleted as coeval terrestrial mammals, suggesting that C3 plants and terrestrial mammals were major dietary resources for the Jomon people. Dietary dependence on marine resources calculated from enamel was significantly lower than that calculated from bone collagen. The discrepancy in isotopic ratios between enamel and collagen and the nitrogen isotope ratio in collagen shows a negative correlation on individual and population levels, suggesting diets with variable proportions of terrestrial and marine resources. CONCLUSION: This study highlights the usefulness of coupling tooth enamel and bone collagen in carbon isotopic studies to reconstruct prehistoric human diet. Am J Phys Anthropol 158:300-311, 2015. © 2015 Wiley Periodicals, Inc.

6.
Nephrol Dial Transplant ; 29(2): 289-300, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24081857

RESUMEN

BACKGROUND: The prevention and restoration of peritoneal damage is a critical mission in peritoneal dialysis (PD). Transplantation of mesothelial cells has been suggested to suppress peritoneal injury during PD. Few studies have examined the efficacy and safety of cell transplantation. We evaluated the paracrine effects of mesothelial transplantation during peritoneal repair using immortalized temperature-sensitive mesothelial cells (TSMCs) in chlorhexidine gluconate (CG)-induced peritoneal fibrosis rats. METHODS: Continuous-infusion pumps containing 8% CG were placed into the abdominal cavity for 21 days. After the removal of the pumps, the TSMCs were injected into the peritoneal cavity at Day 22 (Tx-1 group) or 29 (Tx-2 group). Morphological findings and mRNA expressions of regeneration-related factors were examined at Days 22, 29 and 35. RESULTS: Peritoneal thickness was aggravated in the Tx-1 group. Levels of transforming growth factor (TGF)-ß, vascular endothelial growth factor (VEGF) and matrix metalloproteinase-2 mRNA in the Tx-1 group at Day 35 were comparable with those at Day 22. The levels of Snail, B-Raf and ERK-1, markers of epithelial to mesenchymal transition and of the RAS/MAPK pathway in the Tx-1 group, were significantly higher than those in the Tx-2 group. TGF-ß and VEGF were produced from the transplanted mesothelial cells and the surrounding cells in the Tx-1 group. CONCLUSION: It appears that the paracrine effect of transplanted mesothelial cells during peritoneal repair is associated with its surrounding condition. It is important to determine the most appropriate time for developing peritoneal repair through mesothelial transplantation.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Comunicación Paracrina/genética , Fibrosis Peritoneal/terapia , Trasplante de Células Madre , Animales , Antígenos Transformadores de Poliomavirus/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Células Epiteliales/citología , Células Epiteliales/trasplante , Transición Epitelial-Mesenquimal , Regulación de la Expresión Génica , Inmunohistoquímica , Fallo Renal Crónico/terapia , Masculino , Diálisis Peritoneal , Fibrosis Peritoneal/metabolismo , Fibrosis Peritoneal/prevención & control , Peritoneo/metabolismo , Peritoneo/patología , ARN/genética , Ratas , Ratas Sprague-Dawley , Ratas Transgénicas , Reacción en Cadena en Tiempo Real de la Polimerasa , Temperatura
7.
Semin Dial ; 27(4): E42-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24262039

RESUMEN

Peritoneal dialysis (PD) catheters often become severely dislocated, which may lead to malfunction. With the aim of preventing this complication, we have developed a simple method of fixing the catheter downwards in the peritoneal cavity (fixation technique), a technique that does not require a laparoscope. Sixteen patients were implanted using the conventional placement technique and 25 patients were implanted using the fixation technique. The location of the catheter tip was classified from grade 1 (downward, normal) to 5 (dislocated). The frequency of dislocation (defined as the extended time and/or decrease in volume when draining the PD solution) was measured for both the fixation technique and conventional placement technique. There was a significant difference in grade between the fixation technique (2.72 ± 1.01) and conventional technique (3.92 ± 1.31). The time until first dislocation was significantly different between the fixation technique (59.3 ± 48.1 days) and conventional technique (8.8 ± 14.6 days). The time until any dislocation was significantly different between the fixation technique (69.2 ± 41.9 days) and conventional technique (12.9 ± 13.7 days). Complications were not significantly different between the fixation technique and conventional technique. The fixation technique appears to be simple, safe, and useful for preventing severe dislocation and for lengthening the time until dislocation in PD patients.


Asunto(s)
Catéteres de Permanencia , Fallo Renal Crónico/terapia , Diálisis Peritoneal/instrumentación , Peritoneo/cirugía , Femenino , Estudios de Seguimiento , Humanos , Laparoscopía/métodos , Masculino , Reproducibilidad de los Resultados , Estudios Retrospectivos
8.
J Artif Organs ; 16(1): 66-73, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23010754

RESUMEN

It is well known that bioincompatible peritoneal dialysate plays a central role in the development of peritoneal fibrosis. Peritoneal inflammation continues even after the cessation of peritoneal dialysate stimulation. It is important to establish the definition of persistent inflammation in the peritoneal cavity at the cessation of peritoneal dialysis (PD). The objective of the present study was to determine whether pentraxin 3 (PTX3) in peritoneal effluent (PE) may be a new biomarker in PD patients. Serum, PE, and peritoneal specimens were obtained from 50 patients with end-stage kidney disease at Juntendo University Hospital. Samples of 19 patients were obtained at the initiation of PD and those of 31 patients at the cessation of PD. PTX3, high-sensitivity CRP, and MMP-2 and IL-6 were analyzed. An immunohistological examination using an anti-PTX3 antibody was performed. Expressions of PTX3 were observed in endothelial cells, fibroblasts, and mesothelial cells in the peritoneum. The PTX3 level in PE at the cessation of PD was significantly higher than that at the initiation of PD. Effluent PTX3 levels in patients with a history of peritonitis or a PD duration of more than 8 years were significantly higher than those in patients without peritonitis or patients with a PD duration of <8 years. The PTX3 level was significantly correlated with MMP-2 and IL-6 levels in PE, as well as the thickness of the submesothelial compact zone and the vasculopathy. It appears that PTX3 may be a new biomarker of peritoneal inflammation and progressive fibrosis.


Asunto(s)
Proteína C-Reactiva/metabolismo , Diálisis Peritoneal/efectos adversos , Fibrosis Peritoneal/diagnóstico , Peritoneo/patología , Componente Amiloide P Sérico/metabolismo , Adulto , Anciano , Biomarcadores/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cavidad Peritoneal/patología , Fibrosis Peritoneal/etiología , Fibrosis Peritoneal/metabolismo , Peritoneo/metabolismo
9.
Environ Geochem Health ; 35(2): 239-50, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22965894

RESUMEN

Considering the current poor understanding of the seawater-freshwater (SW-FW) interaction pattern at dynamic hydro-geological boundary of coastal aquifers, this work strives to study tidal effect on groundwater quality using chemical tracers combined with environmental isotopes. In situ measurement data of electrical conductivity and groundwater level along with laboratory measurement data of hydro-chemical species were compared with tidal level data measured by Hydrographic and Oceanographic Department, Saijo City, Japan for time series analysis. Result shows that diurnal tides have significant effect on groundwater level as well as its chemical characteristics; however, the magnitude of effect is different in case of different aquifers. Various scatter diagrams were plotted in order to infer mechanisms responsible for water quality change with tidal phase, and results show that cations exchange, selective movement and local SW-FW mixing were likely to be the main processes responsible for water quality changes. It was also found that geological structure of the aquifers is the most important factor affecting the intensity of tidal effect on water quality.


Asunto(s)
Agua Subterránea/química , Movimientos del Agua , Calidad del Agua , Agua Dulce/química , Japón , Espectrometría de Masas , Agua de Mar/química , Factores de Tiempo
10.
Curr Biol ; 18(10): 769-774, 2008 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-18485710

RESUMEN

Faced with sudden environmental changes, animals must either adapt to novel environments or go extinct. Thus, study of the mechanisms underlying rapid adaptation is crucial not only for the understanding of natural evolutionary processes but also for the understanding of human-induced evolutionary change, which is an increasingly important problem [1-8]. In the present study, we demonstrate that the frequency of completely plated threespine stickleback fish (Gasterosteus aculeatus) has increased in an urban freshwater lake (Lake Washington, Seattle, Washington) within the last 40 years. This is a dramatic example of "reverse evolution,"[9] because the general evolutionary trajectory is toward armor-plate reduction in freshwater sticklebacks [10]. On the basis of our genetic studies and simulations, we propose that the most likely cause of reverse evolution is increased selection for the completely plated morph, which we suggest could result from higher levels of trout predation after a sudden increase in water transparency during the early 1970s. Rapid evolution was facilitated by the existence of standing allelic variation in Ectodysplasin (Eda), the gene that underlies the major plate-morph locus [11]. The Lake Washington stickleback thus provides a novel example of reverse evolution, which is probably caused by a change in allele frequency at the major plate locus in response to a changing predation regime.


Asunto(s)
Adaptación Biológica , Evolución Biológica , Ectodisplasinas/genética , Smegmamorpha/anatomía & histología , Animales , Ecosistema , Flujo Génico , Conducta Predatoria , Selección Genética , Smegmamorpha/genética , Trucha , Washingtón
11.
Sci Total Environ ; 704: 135449, 2020 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-31818581

RESUMEN

The geographic distribution of the stable isotope ratio of Sr (87Sr/86Sr) is useful for identifying the provenance of drinking water, organisms, and agricultural products. To explore how environmental factors influence this ratio, we determined the 87Sr/86Sr, sulfur isotope ratio (δ34S), and elemental composition of 208 commercially available bottled waters in Japan, and compared them with the 87Sr/86Sr values of groundwater, rainwater, rocks, and vegetables from similar localities. We classified the bottled waters into seven categories based on the geology of their source aquifers. The 87Sr/86Sr and concentrations of several elements (Ca, K, Si, Rb, and Ba) of the bottled waters differed with the aquifer rock type and were well correlated with the 87Sr/86Sr of reported spring waters, indicating that bottled water, like other groundwater, reflects the lithology and chemistry of its aquifer. The 87Sr/86Sr of bottled water, taken as a proxy for groundwater, showed regional variations consistent with those of rocks and vegetables, demonstrating that an 87Sr/86Sr map of water and agricultural products has value for determining the production areas of these substances. However, the value and range of 87Sr/86Sr differed among these three materials, and the degree of the difference between groundwater and rock depended on the rock type. An analysis of geochemical data from rocks and rainwater suggests that groundwater contains Sr and additional S derived from atmospheric sources such as rainwater and sea salt aerosols. The atmospheric contribution of Sr to groundwater is greatest in areas of siliceous sedimentary rocks with low Sr concentrations and high resistance to weathering. A weak correlation of δ34S of bottled waters with 87Sr/86Sr indicates the usefulness of maps of combined Sr and S isotope ratios for groundwater provenance. This study shows that for accurate provenance determinations of groundwater, organisms, and agricultural products, it is essential to better quantify the contributions of Sr and S from the atmosphere as well as from rocks and human activities.


Asunto(s)
Agua Potable/análisis , Monitoreo del Ambiente , Isótopos de Estroncio/análisis , Isótopos de Azufre/análisis , Contaminantes Químicos del Agua/análisis , Japón
13.
Sci Total Environ ; 407(9): 3189-97, 2009 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-18495214

RESUMEN

The influence of human activities on the flow system and contamination of groundwater were investigated in Seoul City, South Korea, one of the largest Asian cities, using a combination of isotopes (deltaD, T, delta15N, delta18O, delta34S, and 87Sr/86Sr). Eighteen representative groundwater and river water samples, which were collected over a wide area of the city, were compared with previously reported data. The distribution of stable isotopes (deltaD and delta18O) with groundwater potential data shows that recharged groundwater from either the surrounding mountainous area as well as the Han River and other surface streams discharged towards the northern-central part of the city, where a subway tunnel pumping station is located. It is suggested from T values (3.3 to 5.8 T.U.) that groundwater was recharged in the last 30 to 40 years. The delta34S and delta15N of SO4(2-) and NO3- data were efficiently used as indicators of contamination by human activities. These isotopes clarified that the contribution of anthropogenic contaminants i.e., industrial and household effluents, waste landfills, and fertilizers, are responsible for the enrichment by SO4(2-) (>30 ppm as SO4(2-)) and NO3- (>20 ppm as NO3-) of groundwater. The 87Sr/86Sr values of groundwater vary (0.71326 to 0.75058) in accordance with the host rocks of different origins. Mineral elements such as Ca are also suggested to be derived naturally from rocks. The groundwater under Seoul City is greatly affected by transportation of pollutants along the groundwater flow controlled by subway tunnel pumping, contributing to the degradation of water quality in urbanized areas.


Asunto(s)
Actividades Humanas , Movimientos del Agua , Contaminación del Agua/análisis , Abastecimiento de Agua/análisis , Ciudades , Agua Dulce/química , Humanos , Isótopos/análisis , Corea (Geográfico) , Urbanización
14.
Sci Total Environ ; 389(1): 132-48, 2008 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-17935759

RESUMEN

We investigated the effects of natural environments and human activity on Lake Biwa, central Japan. We determined the concentrations of 19 elements and the compositions of stable S and Sr isotopes in the main tributaries of the lake and compared them with the corresponding values obtained from the lake water during the circulation period. Results of a principal component analysis indicated that the components dissolved in the lower reaches of the tributaries can be divided into group 1 (HCO(3), SO(4), NO(3), Ca, Mg, Sr) and group 2 components (Cl, Br, Na, K, Ba, Rb, Cs). The concentrations of group 1 components were high in the rivers of the southern area, which is urbanized and densely populated, and the eastern area, which consists of plains where agriculture predominates, compared with the rivers of the northern and western areas, which are mostly mountainous and sparsely populated. The concentrations of group 2 components tended to be high in the river water of industrial areas. The delta(34)S values of SO(4) in the river water converged to 0+/-2 per thousand as the SO(4) concentration increased and, excluding the areas where limestone is extensively distributed, as the HCO(3) concentration increased. In particular, both the delta(34)S values (0+/-2 per thousand) and the (87)Sr/(86)Sr ratios (0.7117+/-0.0005) fell within narrow ranges in the small and medium rivers of the eastern plain area, where rice is widely grown. These values agreed respectively with the delta(34)S values of the fertilizers used in the Lake Biwa basin and the soil-exchangeable (87)Sr/(86)Sr in the eastern plain. The characteristics of water quality in the small and medium rivers of the eastern area can be explained by a model in which sulfuric, nitric, and bicarbonic acids generated by the decomposition of agricultural fertilizer and paddy rice selectively leached out alkaline-earth elements adsorbed on the soil and sediments of the plain or dissolved calcium carbonate enriched with Mg and Sr. Compared with tributary waters, the lake water was depleted in NO(3), owing to denitrification, and in Mn, owing to mineralization, which occur under the redox condition of bottom sediments. Excluding NO(3) and Mn, the compositions of both the dissolved elements and the Sr and S isotopes in the water of Lake Biwa can be approximately reproduced by simple mixing of the tributary water, indicating that these components provide effective indices for evaluating the relationship between the waters of the lake and its tributaries.


Asunto(s)
Agricultura , Agua Dulce/química , Contaminantes del Agua/análisis , Monitoreo del Ambiente , Japón , Ríos/química , Azufre/análisis , Isótopos de Azufre/análisis
15.
Sci Total Environ ; 384(1-3): 342-54, 2007 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-17604083

RESUMEN

Sulfur and strontium isotopes (delta(34)S and (87)Sr/(86)Sr) were determined in 39 river water samples collected over three different cultivation periods (April, May, and June), and in several materials used for comparison (fertilizers, detergents, soils, irrigation and agricultural waters), to evaluate the impact of fertilizers on a small agricultural watershed of Lake Biwa, in central Japan. delta(34)S values in river water decreased (from +5.8 to -2.0 per thousand) with increasing SO(4) concentrations (3.8 to 93.2 ppm) from upstream to downstream of the watershed. Comparison of river water S isotopes with those of possible source materials indicates that the enrichment of SO(4) can be attributed to the dissolution of two kinds of fertilizers: (1) compound fertilizers commonly used in this area and (2) ammonium sulfate which is applied on a small scale. In contrast, (87)Sr/(86)Sr values of river water decreased with time from April (avg. 0.71163), through May (avg. 0.71139), to June (avg. 0.71127). The tendency of the sample plots on the (87)Sr/(86)Sr vs. 1/Sr diagram suggests a time-dependent increase in the contribution of soil water to the river, which is partly affected by the Sr-bearing fertilizers. It is suggested that a maximum of 25% of dissolved Sr is derived from these fertilizers, while more than 75% of it is of rock origin. Mass balance calculations permitted us to evaluate the proportion of fertilizer contribution in each river. Combined use of S and Sr isotopes together with concentration data could be a new environmental diagnosis technique for rivers and soils in localized watersheds.


Asunto(s)
Monitoreo del Ambiente , Fertilizantes/análisis , Agua Dulce/química , Isótopos de Estroncio/análisis , Isótopos de Azufre/análisis , Contaminantes Químicos del Agua/análisis , Japón , Metales Pesados/análisis
16.
Food Chem ; 237: 1186-1195, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28763968

RESUMEN

To evaluate the utility of 87Sr/86Sr ratio for determining the geographical provenance of vegetables, we compared 87Sr/86Sr ratios and Sr concentrations in five vegetable species grown in Japan and China, and we also examined the relationships between 87Sr/86Sr ratios in vegetables, the soil-exchangeable pool, irrigation water, and fertilizer from 20 Japanese agricultural areas. The vegetable 87Sr/86Sr ratios in Japan were similar for all species within a given agricultural area, but tended to be low in northeast Japan and high in southwest Japan. The median 87Sr/86Sr ratio in Japanese vegetables was similar to that in fertilizer, suggesting that in addition to rock-derived Sr, vegetables contain Sr derived from fertilizers. In most cases, the 87Sr/86Sr ratios for the Japanese and Chinese vegetables differed by approximately 0.710. Linear discriminant analysis using both 87Sr/86Sr and the Sr concentration allowed more accurate discrimination between vegetables from the two countries.


Asunto(s)
Verduras/química , China , Isótopos , Japón , Estroncio , Isótopos de Estroncio
17.
Anal Sci ; 32(7): 781-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27396661

RESUMEN

The strontium (Sr) isotope ratio ((87)Sr/(86)Sr) and Sr content were used to trace the geographical origin of onions from Japan and other countries, including China, the United States of America, New Zealand, Australia, and Thailand. The mean (87)Sr/(86)Sr ratio and Sr content (dry weight basis) for onions from Japan were 0.70751 and 4.6 mg kg(-1), respectively, and the values for onions from the other countries were 0.71199 and 12.4 mg kg(-1), respectively. Linear discriminant analysis was performed to classify onions produced in Japan from those produced in the other countries based on the Sr data. The discriminant equation derived from linear discriminant analysis was evaluated by 10-fold cross validation. As a result, the origins of 92% of onions were correctly classified between Japan and the other countries.


Asunto(s)
Cebollas/química , Cebollas/clasificación , Estroncio/análisis , Análisis Discriminante , Japón , Modelos Logísticos , Espectrometría de Masas , Cebollas/crecimiento & desarrollo , Espectrofotometría Atómica , Isótopos de Estroncio/análisis
18.
Sci Total Environ ; 345(1-3): 1-12, 2005 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-15919522

RESUMEN

To study the deterioration of the water quality in Lake Biwa, Japan, over the last 40 years, we measured the concentrations and isotopic ratios of sulfur and strontium of water in 41 inflowing rivers and one discharging river. The concentrations of SO4 and Sr of inflowing rivers at downstream sites were generally high in the southern urban area and in the eastern area, where a large agricultural plain is situated, but low in the northern and western areas, whose watersheds are mountainous and with low population density. SO4 and Sr concentrations are also lower at upstream sites, which are closer to mountainous areas. Thus, the inflowing river receives large amounts of SO4 and Sr as it flows across the plain, where human activity levels are high. The delta34S or 87Sr/86Sr values of most eastern rivers at downstream sites are lower than those of water in Lake Biwa, and values become more uniform as the proportion of the plain area in the watershed increases. River water in other areas has higher values of delta34S or 87Sr/86Sr than the lake water. This result indicates that the decadal decrease of delta34S and 87Sr/86Sr in the lake water has been caused mainly by the increased flux of SO4 and Sr from rivers in the eastern plain. We assume that in the plain, sulfur, nitrogen, and organic compounds induced by human activities generate sulfuric, nitric, and organic acids in the water, which accelerate the extraction of Sr from bedrocks, leading to the generation of Sr in the river water in the area.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Actividades Humanas , Ríos/química , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/normas , Agua Dulce/química , Fenómenos Geológicos , Geología , Japón , Isótopos de Estroncio/análisis , Isótopos de Azufre/análisis
19.
Perit Dial Int ; 35(5): 506-16, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25292409

RESUMEN

BACKGROUND: Preventing peritoneal damage during peritoneal dialysis is critical. Reactive oxygen species (ROS) have an important role in peritoneal damage; however, few studies have investigated this. We aimed to determine the effects of oral astaxanthin (AST) supplementation in a peritoneal fibrosis (PF) rat model. METHODS: Thirty-seven Sprague-Dawley rats were divided into 5 groups: Control 1 (fed a normal diet without stimulation), Control 2 (fed an AST-supplemented diet without stimulation), Group 1 (fed a normal diet with 8% chlorhexidine gluconate [CG] stimulation for 3 weeks), Group 2 (fed a 0.06% AST-supplemented diet with CG stimulation), and Group 3 (fed a 0.06% AST-supplemented diet that was initiated 4 weeks before CG stimulation). Peritoneal fibrosis, vascular proliferation, and fibrosis-related factor expression were examined. RESULTS: Peritoneal thickness was significantly suppressed by AST supplementation. Astaxanthin diminished the number of CD68-, 8-hydroxy-2'-deoxyguanosine (8-OHdG)-, and monocyte chemoattractant protein-1 (MCP-1)-positive cells. Type 3 collagen, tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and MCP-1 mRNA expression was significantly lower in Group 3 than in Group 1. Increased transforming growth factor-ß (TGF-ß) and Snail mRNA expression, vascular density, and the number of α-smooth muscle actin (α-SMA)-positive cells were also decreased in Group 3. CONCLUSION: Astaxanthin suppressed PF development through the inhibition of inflammation and oxidation in PF rats. It appears that the anti-oxidative agent AST may be useful for the prevention of peritoneal damage.


Asunto(s)
Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Fibrosis Peritoneal/prevención & control , Peritoneo/patología , 8-Hidroxi-2'-Desoxicoguanosina , Administración Oral , Animales , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Colágeno Tipo III/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Modelos Animales de Enfermedad , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Inflamación/tratamiento farmacológico , Interleucina-1beta/metabolismo , Masculino , Estrés Oxidativo/efectos de los fármacos , Diálisis Peritoneal , Fibrosis Peritoneal/metabolismo , Peritoneo/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor de Necrosis Tumoral alfa/metabolismo , Xantófilas/uso terapéutico
20.
J Nephrol ; 27(5): 507-14, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25146164

RESUMEN

BACKGROUND: Prevention or reversal of peritoneal damage is critical in peritoneal dialysis. Although autologous cell transplantation has beneficial effects on tissue repair in various organs, few studies have investigated the effects of transplantation of adipose-derived mesenchymal stem cells (ASCs) on peritoneal fibrosis (PF). Thus, we examined the mechanism of facilitated peritoneal reconstruction induced by ASC transplantation on chlorhexidine gluconate (CG)-induced PF in rats. METHODS: To induce PF in rats, continuous-infusion pumps containing 8 % CG were placed in the abdominal cavity for 21 days. The pumps were removed on day 22 and ASCs were immediately injected into the peritoneal cavity. Morphological alterations and mRNA expression levels of fibrosis-related factors were examined on days 29 and 35. RESULTS: ASC transplantation significantly facilitated peritoneal repair. mRNA expression of tumor necrosis factor-α, interleukin-1ß, monocyte chemotactic protein-1, and epithelial-mesenchymal transition (EMT) markers such as Snail and α-smooth muscle actin were suppressed, whereas that of vascular endothelial growth factor (VEGF) and platelet-derived growth factor-BB (PDGF-BB) were overexpressed after ASC transplantation. Immunofluorescence indicated that some transplanted ASCs expressed VEGF and PDGF-BB and differentiated into vascular cells. CONCLUSIONS: ASC transplantation facilitates peritoneal repair by suppressing EMT and modulating inflammation and angiogenesis during the early phase of tissue repair in experimental PF.


Asunto(s)
Transición Epitelial-Mesenquimal , Trasplante de Células Madre Mesenquimatosas , Fibrosis Peritoneal/cirugía , Peritoneo/patología , Grasa Subcutánea/citología , Animales , Diferenciación Celular , Células Cultivadas , Clorhexidina/análogos & derivados , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Inyecciones Intraperitoneales , Masculino , Neovascularización Fisiológica , Fibrosis Peritoneal/inducido químicamente , Fibrosis Peritoneal/genética , Fibrosis Peritoneal/metabolismo , Fibrosis Peritoneal/patología , Peritoneo/metabolismo , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Ratas Transgénicas , Factores de Tiempo
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