RESUMEN
Demand for accurate estimation of coastal blue carbon sequestration rates in a regular interval has recently surged due to the increasing awareness of nature-based climate solutions to alleviate adverse impacts stemming from the recent global warming. The robust estimation method is, however, far from well-established. The international community requires, moreover, to quantify its effect of "management." This article tries to provide the environmental isotope community with basic biophysical features of coastal blue carbon ecosystems to identify a suitable set of environmental isotopes for promoting coastal ocean-based climate solutions. This article reviews (i) the primary biophysical characteristics of coastal blue carbon ecosystems and hydrology, (ii) their consequential impact on the accumulation and preservation of organic carbon (OC) in the sediment column, (iii) suitable environmental isotopes to quantifying the sedimentary organic carbon accumulation, outwelling of the carbon-containing byproducts of decomposition of biogenic organic matter and acid neutralizing alkalinity produced in situ sediment to the offshore. Above-ground biomass is not cumulative over the years except for mangrove forests within coastal blue carbon systems. Non-gaseous carbon sequestration and loss occur mainly as a form of sediment organic carbon (SOC) and dissolved carbon in an intertidal and subtidal bottom sediment body in a slow, patchy, and dispersive way, on which this article focuses. Investigating environmental radionuclides is probably the most cost-effective effort to contribute to defining the offshore spatial extent of coastal blue carbon systems except for seagrass beds (e.g., Ra isotopes), to quantify millimeter per year scale carbon accretion and loss within the systems (e.g., 7Be, 210Pb) and a liter per meter of coastline per a day scale water movement from the systems (Ra isotopes). A millimeter-scale spatial and an annual (or less) time-scale resolution offered by the use of environmental isotopes would equip us with a novel tool to enhance the carbon storage capacity of the coastal blue carbon system.
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Secuestro de Carbono , Humedales , Monitoreo del Ambiente/métodos , Carbono , Ecosistema , Sedimentos Geológicos/químicaRESUMEN
The activity concentrations of 210Po were determined in plankton and selected species of macroalgae, crustaceans, molluscs, and fish from Korean coastal waters to understand 210Po distribution in these trophic levels and to assess the effective dose of 210Po from seafood ingested by the average Korean. The activity concentration of 210Po in macroalgae, mixed plankton, anchovy (whole body), abalone muscle, and abalone viscera was 0.97-1.43, 32-137, 59-392, 2.93 ± 0.86, and 1495 ± 484 Bq kg-1 (w.w.), respectively. Polonium-210 concentration in the whole flesh of mussel and oyster were 47.8 ± 5.9 and 45.3 ± 7.1 Bq kg-1 (w.w.), respectively. Polonium-210 concentration in the muscle of the five tested species of fish other than anchovy ranged from 0.51 to 5.56 Bq kg-1 (w.w.), with the lowest amount in a demersal species. In fish, 210Po activity concentration was as much as three orders of magnitude higher in viscera than in muscle. The average annual effective 210Po dose per average Korean adult, who consumes 42.8 kg of seafood a year (excluding anchovy), was estimated to be 94 µSv y-1, with 42-71% of this attributed to shellfish. Further studies are required to assess the dose of 210Po from anchovy owing to its high activity concentration and the manner in which anchovy is consumed.
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Polonio/análisis , Exposición a la Radiación/estadística & datos numéricos , Alimentos Marinos/estadística & datos numéricos , Contaminantes Radiactivos del Agua/análisis , Animales , Biota , Bivalvos , Crustáceos , Peces , Dosis de Radiación , Exposición a la Radiación/análisis , Monitoreo de Radiación , República de CoreaRESUMEN
OBJECTIVE: Bifunctional alpha-bisabolol and phenylethyl resorcinol/TiO2 hybrids were prepared to apply in cosmetic fields, particularly in anti-ageing and hyperpigmentation treatment. The synergistic effect of combined antioxidant and UV filtering properties was achieved through functionalization of TiO2 particles with skin-lightening materials such as alpha-bisabolol and phenylethyl resorcinol. METHODS: TiO2 microspheres with a diameter of about 1 µm were synthesized through surfactant-assisted sol-gel method for use as supporting materials in the formation of hybrid composites. Carboxylation treatment was performed for surface modification of the TiO2 surface with carboxyl groups as chemical binders. Esterification reaction between carboxyl groups of carboxylated TiO2 and hydroxyl groups of alpha-bisabolol or phenylethyl resorcinol was performed. The hybrids were characterized using various techniques such as FE-SEM, DLS, EDS, ATR-FTIR, XPS and TGA. For application of prepared TiO2 composites in the field of cosmetics, the anti-radicular antioxidant abilities were evaluated using ABTS and DPPH colorimetric antioxidant assay. RESULTS: Organic/inorganic hybrid composites were successfully formed using esterification reaction between the carboxyl groups at TiO2 surface and the hydroxyl groups of the skin-lightening materials. The results demonstrate that both functionalized microspheres show scavenging ability towards the ABTS(â¢) and DPPH(â¢) radicals. Specifically, the phenylethyl resorcinol/TiO2 composites exhibited the highest antioxidant ability among the prepared samples owing to the presence of phenolic groups to scavenge free radicals. CONCLUSION: Using this strategy, it could be possible to prepare not only inorganic UV filter but also hybrid organic/inorganic materials with multifunctions and advantages which would be in a great demand for cosmetic applications.
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Cosméticos , Resorcinoles/química , Sesquiterpenos/química , Titanio/química , Antioxidantes/química , Microscopía Electrónica de Rastreo , Sesquiterpenos Monocíclicos , Espectrometría por Rayos X , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
The oceans play a crucial role in the global environment and the sustainability of human populations, because of their involvement in climate regulation and provision of living and non-living resources to humans. Maintenance of healthy oceans in an era of increasing human pressure requires a high-level understanding of the processes occurring in the marine environment and the impacts of anthropogenic activities. Effective protection and sustainable resource management must be based, in part, on knowledge derived from successful research. Current marine research activities are being limited by a need for high-quality researchers capable of addressing critical issues in broad multidisciplinary research activities. This is particularly true for developing countries which will require the building of capacity for marine scientific research. This paper reviews the current activities aimed at increasing marine research capacity in developing and emerging countries and analyses the challenges faced, including: appropriate alignment of the research goals and societal and policy-relevant needs; training in multidisciplinary research; increasing capacity for overall synthesis of scientific data; building the capacity of technical staff; keeping highly qualified personnel in marine scientific research roles; cross-cultural issues in training; minimising duplication in training activities; improving linkages among human capital, project resources and infrastructure. Potential solutions to these challenges are provided, along with some priorities for action aimed at improving the overall research effort.
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Participación de la Comunidad , Conservación de los Recursos Naturales/métodos , Países en Desarrollo , Ambiente , Humanos , Océanos y Mares , InvestigaciónRESUMEN
Human leucocyte antigen (HLA) study in patients with systemic lupus erythematosus (SLE) has been investigated in various countries, but the results are still inconclusive. This study was performed to investigate the association between HLA-DR and SLE in patients in northern Thailand. HLA-DR subtyping was performed in 70 patients with SLE and 99 normal healthy controls living in northern Thailand using the INNO-LiPA HLA-DR Decoder kit (Innogenetics) and MICRO SSP HLA DNA Typing kit (One Lambda) for reconfirmation. The allele frequency (AF) of DRB5*01:01 in SLE was significantly higher than in the controls [25.7% vs. 14.6%, P = 0.012, Pc = 0.048, OR = 2.02 (95%CI = 1.17-3.48)]. The AF of DRB1*15:01 and DRB1*16:02 showed a nonsignificant tendency to be higher in SLE (10.7% vs. 8.1%, and 17.9% vs. 11.1%). Interestingly, the DRB5*01:01 allele linked to DRB1*16:02 in 47.2% of SLE and 37.9% of controls, and the prevalence of the DRB1*16:02-DRB5*01:01 haplotype was higher in the patients with SLE [12.1% vs. 5.6%, P = 0.044, OR = 2.35 (95%CI = 1.06-5.19)]. The DRB1*16:02 linked to DRB5*02:02 and *02:03 in 18.2% and 31.8% of controls, respectively, and linked to DRB5*02:03 in 32.0% of SLE patients. The frequency of DRB1*03:01 and *15:02 alleles was not increased in Thai SLE. There was no significant association between DRB5*01:01 and any auto-antibodies or clinical manifestations of SLE. DRB5*01:01 is associated with Thai SLE, and the association is stronger than that of DRB1*15:01. The genetic contribution of DRB5*01:01 is due partially to the linkage disequilibrium between DRB1*16:02 and DRB5*01:01 in the northern Thai population.
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Cadenas HLA-DRB1/genética , Cadenas HLA-DRB5/genética , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/inmunología , Adulto , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Cadenas HLA-DRB1/inmunología , Cadenas HLA-DRB5/inmunología , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , TailandiaRESUMEN
Massive amounts of anthropogenic radionuclides were released from the nuclear reactors located in Fukushima (northeastern Japan) between 12 and 16 March 2011 following the earthquake and tsunami. Ground level air radioactivity was monitored around the globe immediately after the Fukushima accident. This global effort provided a unique opportunity to trace the surface air mass movement at different sites in the Northern Hemisphere. Based on surface air radioactivity measurements around the globe and the air mass backward trajectory analysis of the Fukushima radioactive plume at various places in the Northern Hemisphere by employing the Hybrid Single-Particle Lagrangian Integrated Trajectory model, we show for the first time, that the uninterrupted complete revolution of the mid-latitude Surface Westerlies took place in less than 21 days, with an average zonal velocity of>60 km/h. The position and circulation time scale of Surface Westerlies are of wide interest to a large number of global researchers including meteorologists, atmospheric researchers and global climate modellers.
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Movimientos del Aire , Contaminantes Radiactivos del Aire/análisis , Accidente Nuclear de Fukushima , Modelos Químicos , Monitoreo de Radiación/estadística & datos numéricos , Radioisótopos/análisis , Monitoreo de Radiación/métodos , Factores de TiempoRESUMEN
Traces of long-lived fallout-derived radioisotopes ((134)Cs and (137)Cs) were found in wet and dry deposition samples collected from the west and east coasts of South Korea from March to May 2011 following the release of radionuclides from the damaged nuclear power plants in Fukushima, Japan. The analysis of air mass back trajectory and atmospheric pressure systems indicated that the Fukushima-derived radiocaesium had predominantly reached South Korea from the west by surface westerlies from 11 March to 5 April; however, after 6 April, air masses arrived from Japan directly due to a high pressure system that developed to the east of Japan. Spatial variation of deposition fluxes of radiocaesium in South Korea was partly attributed to the presence of local longitudinal orography.
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Radioisótopos de Cesio/análisis , Accidente Nuclear de Fukushima , Ceniza Radiactiva , Japón , Conceptos Meteorológicos , República de Corea , Contaminantes Radiactivos del Suelo/análisis , Contaminantes Radiactivos del Agua/análisisRESUMEN
The optimal duration of treatment and expected response rate for hepatitis C virus genotype (HCV-6)-infected patients have not been determined. Our aims were to determine the treatment outcome with pegylated interferon (PEG-IFN) plus ribavirin for HCV-6a-infected patients at Southwest Hospital and assess the association of the on-treatment virological response with the sustained virological response (SVR). Medical records were reviewed retrospectively. Twenty-two HCV-6a-infected patients were treated for 24 weeks, and 21 (95.5%) achieved an early virological response (EVR), 20 (90.9%) an end-of-treatment response (ETR) and 18 (81.8%) a SVR. However, only 18 of the 22 HCV-6a-infected patients were tested for serum HCV RNA level at week 4 of treatment and 15 (83.3%) achieved a rapid virological response (RVR). The rates of SVR, RVR, EVR and ETR in these patients were all similar to those in HCV-2/3 treated for 24 weeks and higher than those in HCV-1b-infected patients treated for 48 weeks. A lower relapse rate (10.0%) was seen in HCV-6a compared with HCV-2/3 (12.5%) or HCV-1b-infected patients (23.3%). The positive predictive values of RVR and EVR for HCV-6a were comparable with those for HCV-2/3-infected patients (86.7%vs 90.9%, P = 0.683 and 85.7%vs 86.8%, P = 0.904, respectively). Of the 3 HCV-6a-infected patients who did not achieve a RVR, 2 achieved an EVR and went on to achieve a SVR. The patient who did not achieve an EVR did not achieve a SVR. In summary, our results indicate that 24 weeks of PEG-IFN plus ribavirin can effectively treat patients with HCV-6a chronic infection.
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Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Ribavirina/administración & dosificación , Adulto , Antivirales/administración & dosificación , Antivirales/uso terapéutico , China , Evaluación de Medicamentos , Quimioterapia Combinada , Estudios de Seguimiento , Genotipo , Hepacivirus/genética , Hepacivirus/patogenicidad , Hepatitis C Crónica/virología , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Masculino , Polietilenglicoles/administración & dosificación , ARN Viral/sangre , Proteínas Recombinantes , Recurrencia , Estudios Retrospectivos , Ribavirina/uso terapéutico , Resultado del TratamientoRESUMEN
The National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) for seaweed was developed through an interlaboratory comparison with 24 participants from 16 countries. After evaluating different techniques to calculate certified values for the radionuclides, the median method was found to be the most representative technique. The certified values were provided for 13 radionuclides and information values were given for 15 more radionuclides. Results for the natural decay series showed disequilibrium in both the uranium and thorium series.
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Guías como Asunto , Monitoreo de Radiación/normas , Radioisótopos/análisis , Radioisótopos/normas , Estándares de Referencia , Algas Marinas/química , Contaminantes Radiactivos del Agua/análisis , Cooperación Internacional , Dosis de Radiación , Monitoreo de Radiación/métodos , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Contaminantes Radiactivos del Agua/normasRESUMEN
OBJECTIVES: The contribution of the microsatellite polymorphisms of TNFa and TNFb, and the TNFB + 252 (TNFB) dimorphism to the pathogenesis of rheumatoid arthritis (RA) was studied among Japanese patients. METHODS: The TNFa and TNFb microsatellite polymorphisms, and the TNFB dimorphism were determined in Japanese RA patients and normal subjects using electrophoresis followed by specific PCR amplification. HLA-DRB1*04 typing was carried out by the PCR-SSCP method. RESULTS: The allele frequency of TNFa11 showed a significant increase in RA with DRB1*0405 when compared to that in RA without DRB1*0405 (28.5% Vs 12.9%, respectively, p = 0.022). An association analysis indicated that TNFa11 was not primary, but secondary to the increase in HLA-DRB1*0405, because TNFa11 showed a strong positive association with HLA-DRB1*0405 in Japanese controls. The slight increase in the TNFb4 allele observed in RA with DRB1*0405 (50.0%) may be reflective of the increase in TNFa11 and DRB1*0405. In RA with DRB1*0405, the allele frequency of TNFB*2 significantly increased compared to that of normal controls (75.0% Vs 55.3%, respectively, p = 0.007) and compared to that of RA without DRB1*0405 (45.0%, p = 0.001). No significant positive association of TNFB*2 with HLA-DRB1*0405 or TNFa11 in Japanese controls might suggest that the increase in the TNFB*2 allele might not be secondary to the increase in DRB1*0405, and that TNFB*2 might contribute additively to DRB1*0405-positive RA in Japanese. CONCLUSION: TNFB*2 may contribute additively to Japanese RA with HLA-DRB1*0405, while TNFa11 and TNFb4 are not independent genetic markers of RA among Japanese.
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Alelos , Artritis Reumatoide/genética , Predisposición Genética a la Enfermedad , Linfotoxina-alfa/genética , Repeticiones de Microsatélite , Factor de Necrosis Tumoral alfa/genética , Artritis Reumatoide/etnología , Femenino , Frecuencia de los Genes , Marcadores Genéticos , Antígenos HLA-DR/análisis , Cadenas HLA-DRB1 , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo GenéticoRESUMEN
The contribution of the tumour necrosis factor (TNF) B + 252 (TNFB) dimorphism and microsatellite polymorphisms of TNFa and TNFb to the pathogenesis of systemic lupus erythematosus (SLE) was studied in Japanese patients. The TNFB dimorphism was determined using the restriction fragment length polymorphism (RFLP) method with NcoI digestion followed by specific polymerase chain reaction (PCR) amplification. TNFa and TNFb microsatellite polymorphisms were determined using the DNA sequencer and GeneScan program (Applera Corporation, Foster City, CA) followed by specific PCR amplification. HLA-DRB1*15 typing was carried out by the PCR-sequence specific conformational polymorphism (SSCP) method. In SLE, the allele frequency of TNFB*2 significantly increased (68.9%, P < 0.05) and the genotype frequency of TNFB*2/2 also increased (52.8%, P < 0.05). TNFB*2 showed no significant linkage disequilibrium with HLA-DRB1*1501. The prevalence of TNFa13 and TNFb4 showed very slight increases, but these increases were not significant. An association analysis indicated that TNFB*2/2 conferred greater, or at least equal, susceptibility to SLE in Japanese patients in comparison with HLA-DRB1*1501. The TNFB*2/2 genotype may contribute additively with DRB1*1501 to SLE in Japanese patients. No association was observed between auto-antibodies and TNF. TNFB*2 is a genetic marker for SLE in Japanese patients, while TNFa and TNFb microsatellites are not associated with SLE.
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Alelos , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/inmunología , Linfotoxina-alfa/genética , Repeticiones de Microsatélite/genética , Factor de Necrosis Tumoral alfa/genética , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Antígenos HLA-DR/genética , Subtipos Serológicos HLA-DR , Humanos , Japón , Polimorfismo GenéticoRESUMEN
137Cs and (239+240)Pu data in seawater, sediment and biota from the regional seas of Asia-Pacific extending from 50 degrees N to 60 degrees S latitude and 60 degrees E to 180 degrees E longitude based on the Asia-Pacific Marine Radioactivity Database (ASPAMARD) are presented and discussed. 137Cs levels in surface seawater have been declining to its present median value of about 3 Bq/m3 due mainly to radioactive decay, transport processes, and the absence of new significant inputs. (239+240)Pu levels in surface seawater are much lower, with a median of about 6 mBq/m3. (239+240)Pu appears to be partly scavenged by particles and is therefore more readily transported down the water column. As with seawater, (239+240)Pu concentrations are lower than 137Cs in surface sediment. The median 137Cs concentration in surface sediment is 1.4 Bq/kg dry, while that of (239+240)Pu is only 0.2 Bq/kg dry. The vertical profiles of both 137Cs and (239+240)Pu in the sediment column of coastal areas are different from deep seas which can be attributed to the higher sedimentation rates and additional contribution of run-offs from terrestrial catchment areas in the coastal zone. Comparable data for biota are far less extensive than those for seawater and sediment. The median 137Cs concentration in fish (0.2 Bq/kg wet) is higher than in crustaceans (0.1 Bq/kg wet) or mollusks (0.1 Bq/kg wet). Benchmark values (as of 2001) for 137Cs and (239+240)Pu concentrations in seawater, sediment and biota are established to serve as reference values against which the impact of future anthropogenic inputs can be assessed. ASPAMARD represents one of the most comprehensive compilations of available data on 137Cs and (239+240)Pu in particular, and other anthropogenic as well as natural radionuclides in seawater, sediment and biota from the Asia-Pacific regional seas.
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Cadena Alimentaria , Plutonio/análisis , Contaminantes Radiactivos del Agua/análisis , Animales , Radioisótopos de Cesio/análisis , Crustáceos , Monitoreo del Ambiente , Sedimentos Geológicos/química , Moluscos , Océano Pacífico , Agua de Mar/química , Distribución TisularRESUMEN
239+240Pu concentrations and 240Pu/239Pu atom ratios in coastal seas adjacent to the Korean Peninsula were determined, during the period 1999 to 2002, to assess the current distribution and to identify sources of Pu isotopes. 239+240Pu concentrations in surface waters ranged from 3.1 to 22.3 mBq m(-3) with higher concentrations in winter than in summer. 239+240Pu concentrations in seawaters around the Korean Peninsula are greater than that in the western North Pacific. 240Pu/239Pu atom ratios ranged from 0.18 to 0.33 with an average value of 0.25+/-0.03, which is significantly higher than the global fallout average. The 240Pu/239Pu atom ratios of the 2000 m deep entire water column in the south western part of the East Sea (Sea of Japan) was comparable to that observed in waters near Bikini Atoll. The higher 240Pu/239Pu atom ratios than that of global fallout may be explained by the hypothesis that the earlier input signal of low 240Pu/239Pu atom ratio (0.18-0.19) of global fallout plutonium in seas adjacent to the Korean Peninsula is being gradually diluted by the high 240Pu/239Pu atom ratio plutonium transported from the tropical Pacific Proving Grounds via prevailing ocean current.
RESUMEN
Marine mammals being among the top predators in the food web tend to accumulate organic and inorganic contaminants from the environment. The body burden of contaminants in these species could reflect their foods and thus contaminant levels could serve as proxies on the changes of ecosystem. A pilot study was carried out to investigate the possibility of radionuclide leakage at Amchitka using a suite of sea otter (Enhydra lutris) skulls collected near Amchitka nuclear test-sites before (1950s) and after the testing (1990s), and at Adak, another Aleutian Island, about 300 km from Amchitka, where the potential impact of radionuclide leakage from Amchitka is expected to be negligible. In addition, the naturally occurring and anthropogenic radionuclide content on the sea otter skull was also utilized to investigate if there was any significant ecosystem changes in the environment. Concentration of 210Pb in sea otter bones collected during the 1950s was significantly higher than those collected in the 1990s. We propose that among the various factors that could cause this higher enrichment in 210Pb, changes in the sea otter prey is the most likely one. Comparison of the 137Cs, 90Sr, 239,240Pu concentrations appear not to be significantly higher in sea otter skulls collected in 1990s from Amchitka where the underground tests in 1965-71 than those from Adak, although significant differences were detected among different groups collected at various times.
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Nutrias , Radioisótopos/farmacocinética , Cráneo/química , Contaminantes Radiactivos del Agua/farmacocinética , Animales , Ecosistema , Cadena Alimentaria , Guerra Nuclear , Radioisótopos/análisis , Factores de Tiempo , Contaminantes Radiactivos del Agua/análisisRESUMEN
The concentrations of 239+240Pu and 137Cs in zooplankton and nekton in the Northwest Pacific and Southern Oceans were measured during the period 1993-1996. The object of the sampling was to assess the potential impacts of existing submerged anthropogenic-radioactive materials in the western North Pacific as well as the East China Sea. Samples from the Bransfield Strait of the Antarctic Ocean provided a control source impacted by only atmospheric bomb fallout. No particularly elevated levels of 239+240Pu were found in zooplankton samples from the Northwest Pacific, although significantly lower levels of 239+240Pu were found in three mixed zooplankton samples from the Bransfield Strait. The body burden of 239+240Pu in zooplankton appears to reflect concentrations in ambient seawater with some variation. Some additional measurements of 137Cs in fish are also reported here to complement existing databases and for future reference in the regional marine environmental radioactivity monitoring effort.
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Cesio/efectos adversos , Plutonio/efectos adversos , Contaminantes Radiactivos del Agua/efectos adversos , Zooplancton , Animales , Regiones Antárticas , Carga Corporal (Radioterapia) , Cesio/análisis , Radioisótopos de Cesio/análisis , Plutonio/análisis , Dinámica PoblacionalRESUMEN
Water sampling during the 1993 IV Russian-US Joint Expedition to the Bering and Chukchi Seas (BERPAC) indicates that Pacific Ocean burdens of the long-lived radionuclide 129I are relatively low in the Pacific-influenced Arctic, particularly compared to high latitude waters influenced by the North Atlantic. These low concentrations occur despite the presence of potential submerged anthropogenic sources in the East Sea (Sea of Japan), and in the northwest Pacific Ocean, east of the Kamchatka Peninsula. The concentration of 129I entering the Arctic Ocean through Bering Strait, approximately 0.7 x 10(8) atoms kg(-1), is only slightly higher than observed in deep Pacific waters. Similar concentrations (0.44-0.76 x 10(8) atoms kg(-1)) measured in Long Strait indicate no significant transfer of 129I eastward into the Chukchi Sea in the Siberian Coastal Current from the Siberian marginal seas to the west. However, the concentrations reported here are more than an order of magnitude higher than the Bering Strait input concentration estimated (1.0 x 10(6) atoms kg(-1)) from bomb fallout mass balances, which supports other existing evidence for a significant atmospheric deposition term for this radionuclide in surface ocean waters. Near-bottom water samples collected in productive waters of the Bering and Chukchi Seas also suggest that sediment regeneration may locally elevate 129I concentrations, and impact its utility as a water mass tracer. As part of this study, two deep 129I profiles were also measured in the East Sea in 1993-1994. The near-surface concentration of 129I ranged from 0.12 to 0.31 x 10(8) atoms kg(-1). The 129I concentration showed a steady decrease with depth, although because of active deep water ventilation, the entire 3000 m water column exceeded natural concentrations of the radionuclide. Atom ratios of 129I/137Cs in the East Sea also suggest an excess of 129I above bomb fallout estimates, also possibly resulting from atmospheric deposition ultimately originating from nuclear facilities.
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Radioisótopos de Yodo/análisis , Agua de Mar/análisis , Contaminantes Radiactivos del Agua/análisis , Regiones Árticas , Monitoreo del Ambiente , Japón , Océano PacíficoRESUMEN
Large quantities of radioactive wastes have been dumped in the Far Eastern Seas by the former Soviet Union and the Russian Federation, and small amounts of radioactive wastes have been dumped by Japan and the Republic of Korea. In order to investigate the concentrations of anthropogenic radionuclides in the nine dumping areas, a second expedition was conducted in 1995 by Japan, the Republic of Korea, the Russian Federation and IAEA, following the first expedition in 1994. The results show that 137Cs, 90Sr and 239 + 240Pu concentrations in surface and bottom waters at dumping areas do not significantly differ from the values observed in background areas, and from historical values. There is no clear effect of possible contamination due to radioactive waste dumping. The concentrations and water column inventories of 137Cs, 90Sr and 239 + 240Pu in the Far Eastern seas are controlled by physical oceanic processes such as horizontal transport and biogeochemical processes such as scavenging.
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Monitoreo de Radiación , Radioisótopos/análisis , Agua de Mar/análisis , Contaminantes Radiactivos del Agua/análisis , Contaminación Radiactiva del Agua/análisis , Radioisótopos de Cesio/análisis , Asia Oriental , Cooperación Internacional , Océanos y Mares , Océano Pacífico , Plutonio/análisis , Residuos Radiactivos , Radioisótopos de Estroncio/análisisRESUMEN
Sediment cores collected from the deep basins of the East Sea (Sea of Japan) provide an ongoing and historical record of artificial radionuclides contamination into one of the most highly publicized radioactive waste dumping areas in the world ocean. The depth distributions of 90Sr, 137Cs and 239,240Pu in sediment cores were investigated with the aid of 210Pb-derived sediment accumulation and mixing rates in the deep basins of the East Sea (Sea of Japan). Five box core samples were collected from the northern Yamato Ridge, Korea Plateau, Ulleung and Japan Basins below 1000-m depth. Sediment inventories of 137Cs and 239,240Pu are inversely correlated with water depth and linearly correlated with sediment accumulation rates. The inventories of these nuclides are linearly correlated with the accumulation rates of organic carbon in sediments. The 238Pu/239,240Pu activity ratios in sediments are 0.036 +/- 0.009 suggesting that most of the Pu to the study area is derived from the global fallout. The activity ratios of 239,240Pu/137Cs, and 90Sr/137Cs in bottom sediments are much lower than those of global fallout due to the differences of particle affinity and biological uptake of these nuclides. Sediment inventories of 90Sr and 137Cs constitute < 4% of the anticipated inventories from the global fallout, while those of 239,240Pu constitute 30-150% of the anticipated inventories from the global fallout. The residence time of the dissolved 239,240Pu in the study area is estimated to be 200-400 years based on the sediment inventory and/or sediment accumulation rate, and water column inventory.
Asunto(s)
Sedimentos Geológicos/química , Monitoreo de Radiación , Radioisótopos/análisis , Contaminantes Radiactivos del Agua/análisis , Contaminación Radiactiva del Agua/análisis , Cesio/análisis , Japón , Radioisótopos de Plomo/análisis , Reactores Nucleares , Océano Pacífico , Plutonio/análisis , Ceniza Radiactiva , Residuos Radiactivos , Radioisótopos de Estroncio/análisisRESUMEN
OBJECTIVE: The contribution of the polymorphism of complement C4A and C4B alleles to the pathogenesis of systemic sclerosis (SSc) was studied in Japanese patients. METHODS: C4A and C4B typing was carried out in 44 SSc patients and in 83 normal subjects using electrophoresis followed by immunofixation and immunoblotting. HLA-DR typing and HLA DRB1*15 and *08 genotyping were carried out by the PCR method and the PCR-SSCP method, respectively. RESULTS: In SSc with diffuse scleroderma, the frequency of C4BQ0 was significantly increased (44.4%, p < 0.001, pc < 0.01). In SSc with antitopoisomerase I antibody (a-Scl-70) C4BQ0 was also increased (50.0%, p < 0.001, pc < 0.01). Association analysis indicated that the increase in C4BQ0 was not primary but reflected an increase in HLA-DRB1*1502. In contrast, C4A/Q0 was significantly increased in limited scleroderma (53.8%, p < 0.005, pc < 0.05) and SSc without a-SCL-70 (53.8%, p < 0.005, pc < 0.05). CONCLUSION: Diffuse scleroderma with SSC with a-Scl-70 have different genetical backgrounds from limited scleroderma and SSc without a-Scl-70, respectively, in Japanese patients. C4AQ0 were independent genetic markers for each clinical subgroup and for a a-Scl-70 positivity.
Asunto(s)
Complemento C4a/genética , Complemento C4b/genética , Esclerodermia Sistémica/genética , Esclerodermia Sistémica/inmunología , Adulto , Anciano , Alelos , Femenino , Marcadores Genéticos , Antígenos HLA-DR/genética , Subtipos Serológicos HLA-DR , Cadenas HLA-DRB1 , Prueba de Histocompatibilidad , Humanos , Japón , Masculino , Persona de Mediana Edad , Fenotipo , Polimorfismo GenéticoRESUMEN
Associations between polymorphisms of DMA and DMB alleles and systemic lupus erythematosus (SLE) were studied in 51 Japanese SLE patients and 77 normal subjects by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Phenotype frequencies of DMB*0101 tended to increase in SLE, but the difference was not significant (76.5% vs 70.1% in controls). The phenotype frequency of DMB*0103 was decreased in the SLE group, but the difference was not significant (49.0% vs 53.2%). Furthermore, there was no evidence of any association of either DMA or DMB alleles with HLA-DRB1*1501. The phenotype frequency of DMB*0101 was higher in the SLE group with anti-double-stranded DNA antibody (a-dsDNA) than in the SLE group without a-dsDNA, but the difference was not significant (P = 0.045, corrected P not significant). No other DMA or DMB alleles showed any associations in various immunological subgroups of SLE. These data suggest that neither the DMA nor the DMB gene determines susceptibility to SLE in Japanese.