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<p> The distribution of manganese in blood serum and erythrocytes has been investigated using a combination of radioactive tracer method with both gel chromatography and disc gel electrophoresis. </p> <p> In serum, there are two manganese-binding proteins. The first is a(beta)1 globulin with a molecular weight of 70,000. This forms a relatively labile manganese complex both in vitro and in vivo, and is remarkably similar in both its chromatographic and electrophoretic behaviour to the iron-binding protein, transferrin. The second protein is a higher molecular weight (beta) globulin. It is found to incorporate radiomanganese in vivo only, thereupon forming a very stable entity. </p> <p> In erythrocytes, manganese occurs predominantly in a porphyrin bound to apoglobin, giving rise to a species similar to hemoglobin . </p> / Thesis / Doctor of Philosophy (PhD)

A contaminação do ambiente é crescente no mundo, com grandes extensões de áreas afetadas por metais pesados em concentrações que podem representar perigo ambiental. Em face ao aumento da atividade industrial e à agricultura altamente tecnificada, é fundamental o monitoramento dos níveis de metais pesados nos solos, já que as plantas se comportam como mecanismo de transferência de contaminantes do solo para níveis mais altos da cadeia trófica. A ingestão de vegetais contendo elevadas concentrações de metais pesados é uma das principais vias de acesso desses elementos ao corpo humano. No corpo humano, os metais pesados depositam-se no tecido ósseo e gorduroso, ocupando o lugar de minerais nobres. Lentamente liberados no organismo, podem provocar uma série de doenças. O projeto foi dividido em três etapas, cada qual com um objetivo específico: 1º) determinar as concentrações de cádmio, níquel, chumbo, cobalto e cromo em vegetais frequentemente consumidos no Estado de São Paulo, e compará-las com os limites estabelecidos na legislação brasileira; calcular a ingestão diária de metais pesados para estimar o risco à saúde humana; identificar as culturas que apresentam maior potencial de translocação de cádmio para a cadeia alimentar 2º) avaliar os teores de cádmio em hortaliças e nos solos dos campos de produção 3º) avaliar a disponibilidade de cádmio do solo para as plantas com maior potencial de acúmulo do mesmo, com auxilio de extratores químicos e pela técnica de traçador radioativo (109Cd). As amostras vegetais foram coletadas na Companhia de Entrepostos e Armazéns Gerais de São Paulo e a concentração de metais pesados foi determinada por espectrometria de absorção atômica. Todos os vegetais analisados apresentaram concentrações de Cd e Ni abaixo do limite tolerável estabelecido pela legislação brasileira. No entanto, para Pb e Cr, 44% das amostras excederam o limite permitido. Não há nenhuma recomendação estabelecida de limite máximo de tolerância para Co no Brasil. Quanto ao hábito de consumo da população do Estado de São Paulo, a ingestão diária de metais pesados está abaixo da máxima permitida, consequentemente o consumo desses alimentos pode ser considerado seguro e sem riscos à saúde humana. As hortaliças folhosas foram as que mais acumularam Cd. Algumas regiões do Estado de São Paulo apresentaram teores totais de Cd no solo acima do valor de intervenção estabelecido pela CETESB. Entretanto, os vegetais cultivados nesses locais apresentaram teores de Cd inferiores ao limite máximo de tolerância, estabelecido pela ANVISA. É importante, ao estudar a contaminação de áreas agrícolas por metais pesados, observar, além do teor total, outros parâmetros, como a sua disponibilidade para plantas. No experimento em casa de vegetação, as correlações entre o Cd disponível do solo e o Cd acumulado pelas plantas foram significativas somente para a rúcula. O extrator mais eficiente em determinar a fitodisponibilidade de Cd, analisado por meio do Valor L e Razão L, foi o extrator Ácidos Orgânicos / The environmental contamination is increasing worldwide, with large areas affected by heavy metals at concentrations which may pose environmental hazard. Due to industrial activity and highly technical agriculture, it is important to monitor heavy metals levels in soils, since vegetables behave as transfer mechanism of contaminants from soils to higher levels of the food chain. Ingestion of vegetables containing high concentrations of heavy metals is one of the main ways in which these elements enter the human body. Once in human body, heavy metals are deposited in the bone and fat tissues, overlapping noble minerals. Slowly released into the body, heavy metals may cause an array of diseases. The project was divided into three stages, each one with a specific objective: 1st) to determine the concentrations of cadmium, nickel, lead, cobalt and chromium in the most frequently consumed foodstuff in the São Paulo State, Brazil and to compare the heavy metal contents with the permissible limits established by the Brazilian legislation; to calculate intake of heavy metals in human diets for estimating the risk to human health; and to identify crops with the greatest potential for translocation of cadmium into food chain 2nd) to evaluate the cadmium content in leafy vegetables and soils at crop fields 3th) evaluate the phytoavailability of cadmium for leafy vegetables with aid of chemical extractants and radioactive tracer technique (109Cd). The vegetable samples were collected at São Paulo General Warehousing and Centers Company, and heavy metal content was determined by atomic absorption spectrophotometry. All vegetables sampled presented average concentrations of Cd and Ni lower than the permissible limits established by the Brazilian legislation. Exception for Pb and Cr in that 44% of the samples exceeded the maximum permitted limits. The Brazilian legislation has not established a permissible limit for Co contents. Regarding the consumption habit of the population in the São Paulo State, the daily ingestion of heavy metals is below the oral dose of reference, therefore, the consumption of these vegetables can be considered safe and without risk to human health. Leafy vegetables were those most accumulated Cd. Some regions of São Paulo State showed total contents of Cd in soil higher than intervention value established by CETESB. However, the vegetables grown in these areas showed Cd concentrations lower than Brazilian limit established by ANVISA. It is important, when studying environmental contamination by heavy metals, to observe, beside their total content, other parameters, like soil availability. In the greenhouse experiment, the correlation between soil available Cd and plants accumulated Cd were significant only for rocket. The most efficient chemical extractant in determining Cd phytoavailability, analyzed by L Value and L Ratio, were Organic Acids

Two problems hampering efforts to produce salt-tolerant plants through constitutive expression of transgenes include: 1. Spatial control. Particular cell-types must respond specifically to salt stress to minimise the amount of Na⁺ delivered to the shoot; and, 2. Temporal control. Transgenes are typically expressed in plants at similar levels through time, irrespective of the stress encountered by the plant, which may exacerbate pleiotropic effects and means that, particularly in low-stress conditions, costly and/or detrimental metabolic processes may be active, thus reducing yield. To address these issues, Gateway® destination vector constructs were developed combining the GAL4 UAS (upstream activating sequence) with the ethanol-inducible gene expression system to drive inducible cell-specific expression of Na⁺ transporter transgenes (or to silence salt transporter transgenes inducibly and cell-specifically). Rice (Oryza sativa L. cv. Nipponbare) GAL4-GFP enhancer trap lines (Johnson et al., 2005: Plant J. 41, 779-789) that express GAL4 and GFP specifically in either the root epidermis or xylem parenchyma (and therefore ‘trap’ cell-type specific enhancer elements) were transformed with this GAL4 UAS – ethanol switch construct, thereby allowing both spatial and temporal control of transgenes. In preliminary experiments, the expression system successfully limited the expression of RFP to specific cell-types after induction with ethanol. Other genes expressed using this system include PpENA1, a Na⁺-extruding ATPase from the moss, Physcomitrella patens, and AtHKT1;1, a Na ⁺ transporter from Arabidopsis thaliana. The two enhancer trap rice lines were also transformed with the GAL4 UAS driving stable expression of AtHKT1;1 and PpENA1 specifically in root epidermal or xylem parenchyma cells. Expression of AtHKT1;1 in root epidermal cells reduced Na⁺ accumulation in the shoots, while expression in the root xylem parenchyma appeared to have little effect on shoot Na⁺ accumulation. Using cryo-scanning electron microscopy (SEM) X-ray microanalysis, the outer cells of the roots of the line expressing AtHKT1;1 in the epidermal cells were found to accumulate higher levels of Na⁺ than the parental enhancer trap line. Additionally, this line had decreased unidirectional ²²Na⁺ influx. Similar results were observed for plants expressing AtHKT1;1 driven by the CaMV 35S / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1325289 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008

Two problems hampering efforts to produce salt-tolerant plants through constitutive expression of transgenes include: 1. Spatial control. Particular cell-types must respond specifically to salt stress to minimise the amount of Na⁺ delivered to the shoot; and, 2. Temporal control. Transgenes are typically expressed in plants at similar levels through time, irrespective of the stress encountered by the plant, which may exacerbate pleiotropic effects and means that, particularly in low-stress conditions, costly and/or detrimental metabolic processes may be active, thus reducing yield. To address these issues, Gateway® destination vector constructs were developed combining the GAL4 UAS (upstream activating sequence) with the ethanol-inducible gene expression system to drive inducible cell-specific expression of Na⁺ transporter transgenes (or to silence salt transporter transgenes inducibly and cell-specifically). Rice (Oryza sativa L. cv. Nipponbare) GAL4-GFP enhancer trap lines (Johnson et al., 2005: Plant J. 41, 779-789) that express GAL4 and GFP specifically in either the root epidermis or xylem parenchyma (and therefore ‘trap’ cell-type specific enhancer elements) were transformed with this GAL4 UAS – ethanol switch construct, thereby allowing both spatial and temporal control of transgenes. In preliminary experiments, the expression system successfully limited the expression of RFP to specific cell-types after induction with ethanol. Other genes expressed using this system include PpENA1, a Na⁺-extruding ATPase from the moss, Physcomitrella patens, and AtHKT1;1, a Na ⁺ transporter from Arabidopsis thaliana. The two enhancer trap rice lines were also transformed with the GAL4 UAS driving stable expression of AtHKT1;1 and PpENA1 specifically in root epidermal or xylem parenchyma cells. Expression of AtHKT1;1 in root epidermal cells reduced Na⁺ accumulation in the shoots, while expression in the root xylem parenchyma appeared to have little effect on shoot Na⁺ accumulation. Using cryo-scanning electron microscopy (SEM) X-ray microanalysis, the outer cells of the roots of the line expressing AtHKT1;1 in the epidermal cells were found to accumulate higher levels of Na⁺ than the parental enhancer trap line. Additionally, this line had decreased unidirectional ²²Na⁺ influx. Similar results were observed for plants expressing AtHKT1;1 driven by the CaMV 35S / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1325289 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008

Two long-lived halogen radionuclides (36Cl, T1/2 = 301 kyr, and 129I, T1/2 = 15.7 Myr) have been studied by means of Accelerator Mass Spectrometry (AMS) at the Uppsala Tandem Laboratory. The 36Cl measurements in natural samples using a medium-sized tandem accelerator (~1 MeV/amu) have been considered. A gas-filled magnetic spectrometer (GFM) was proposed for the separation of 36Cl from its isobar, 36S. Semi-empirical Monte-Carlo ion optical calculations were conducted to define optimal conditions for separating 36Cl and 36S. A 180° GFM was constructed and installed at the dedicated AMS beam line. 129I has been measured in waters from the Arctic and North Atlantic Oceans. Most of the 129I currently present in the Earth's surface environment can be traced back to liquid and gaseous releases from the nuclear reprocessing facilities at Sellafield (UK) and La Hague (France). The anthropogenic 129I inventory in the central Arctic Ocean was found to increase proportionally to the integrated 129I releases from these reprocessing facilities. The interaction and origin of water masses in the region have been clearly distinguished with the help of 129I labeling. Predictions based on a compartment model calculation showed that the Atlantic Ocean and deep Arctic Ocean are the major sinks for the reprocessed 129I. The variability in 129I concentration measured in seawater along a transect from the Baltic Sea to the North Atlantic suggests strong enrichment in the Skagerrak–Kattegat basin. The 129I inventory in the Baltic and Bothnian Seas is equal to ~0.3% of the total liquid releases from the reprocessing facilities. A lake sediment core sampled in northeastern Ireland was analyzed for 129I to study the history of the Sellafield releases, in particular the nuclear accident of 1957. High 129I concentration was observed corresponding to 1990 and later, while no indication of the accident was found. The results of this thesis research clearly demonstrate the uniqueness and future potential of 129I as a tracer of processes in both marine and continental archives.

Two problems hampering efforts to produce salt-tolerant plants through constitutive expression of transgenes include: 1. Spatial control. Particular cell-types must respond specifically to salt stress to minimise the amount of Na⁺ delivered to the shoot; and, 2. Temporal control. Transgenes are typically expressed in plants at similar levels through time, irrespective of the stress encountered by the plant, which may exacerbate pleiotropic effects and means that, particularly in low-stress conditions, costly and/or detrimental metabolic processes may be active, thus reducing yield. To address these issues, Gateway® destination vector constructs were developed combining the GAL4 UAS (upstream activating sequence) with the ethanol-inducible gene expression system to drive inducible cell-specific expression of Na⁺ transporter transgenes (or to silence salt transporter transgenes inducibly and cell-specifically). Rice (Oryza sativa L. cv. Nipponbare) GAL4-GFP enhancer trap lines (Johnson et al., 2005: Plant J. 41, 779-789) that express GAL4 and GFP specifically in either the root epidermis or xylem parenchyma (and therefore ‘trap’ cell-type specific enhancer elements) were transformed with this GAL4 UAS – ethanol switch construct, thereby allowing both spatial and temporal control of transgenes. In preliminary experiments, the expression system successfully limited the expression of RFP to specific cell-types after induction with ethanol. Other genes expressed using this system include PpENA1, a Na⁺-extruding ATPase from the moss, Physcomitrella patens, and AtHKT1;1, a Na ⁺ transporter from Arabidopsis thaliana. The two enhancer trap rice lines were also transformed with the GAL4 UAS driving stable expression of AtHKT1;1 and PpENA1 specifically in root epidermal or xylem parenchyma cells. Expression of AtHKT1;1 in root epidermal cells reduced Na⁺ accumulation in the shoots, while expression in the root xylem parenchyma appeared to have little effect on shoot Na⁺ accumulation. Using cryo-scanning electron microscopy (SEM) X-ray microanalysis, the outer cells of the roots of the line expressing AtHKT1;1 in the epidermal cells were found to accumulate higher levels of Na⁺ than the parental enhancer trap line. Additionally, this line had decreased unidirectional ²²Na⁺ influx. Similar results were observed for plants expressing AtHKT1;1 driven by the CaMV 35S / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1325289 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008

A contaminação do ambiente é crescente no mundo, com grandes extensões de áreas afetadas por metais pesados em concentrações que podem representar perigo ambiental. Em face ao aumento da atividade industrial e à agricultura altamente tecnificada, é fundamental o monitoramento dos níveis de metais pesados nos solos, já que as plantas se comportam como mecanismo de transferência de contaminantes do solo para níveis mais altos da cadeia trófica. A ingestão de vegetais contendo elevadas concentrações de metais pesados é uma das principais vias de acesso desses elementos ao corpo humano. No corpo humano, os metais pesados depositam-se no tecido ósseo e gorduroso, ocupando o lugar de minerais nobres. Lentamente liberados no organismo, podem provocar uma série de doenças. O projeto foi dividido em três etapas, cada qual com um objetivo específico: 1º) determinar as concentrações de cádmio, níquel, chumbo, cobalto e cromo em vegetais frequentemente consumidos no Estado de São Paulo, e compará-las com os limites estabelecidos na legislação brasileira; calcular a ingestão diária de metais pesados para estimar o risco à saúde humana; identificar as culturas que apresentam maior potencial de translocação de cádmio para a cadeia alimentar 2º) avaliar os teores de cádmio em hortaliças e nos solos dos campos de produção 3º) avaliar a disponibilidade de cádmio do solo para as plantas com maior potencial de acúmulo do mesmo, com auxilio de extratores químicos e pela técnica de traçador radioativo (109Cd). As amostras vegetais foram coletadas na Companhia de Entrepostos e Armazéns Gerais de São Paulo e a concentração de metais pesados foi determinada por espectrometria de absorção atômica. Todos os vegetais analisados apresentaram concentrações de Cd e Ni abaixo do limite tolerável estabelecido pela legislação brasileira. No entanto, para Pb e Cr, 44% das amostras excederam o limite permitido. Não há nenhuma recomendação estabelecida de limite máximo de tolerância para Co no Brasil. Quanto ao hábito de consumo da população do Estado de São Paulo, a ingestão diária de metais pesados está abaixo da máxima permitida, consequentemente o consumo desses alimentos pode ser considerado seguro e sem riscos à saúde humana. As hortaliças folhosas foram as que mais acumularam Cd. Algumas regiões do Estado de São Paulo apresentaram teores totais de Cd no solo acima do valor de intervenção estabelecido pela CETESB. Entretanto, os vegetais cultivados nesses locais apresentaram teores de Cd inferiores ao limite máximo de tolerância, estabelecido pela ANVISA. É importante, ao estudar a contaminação de áreas agrícolas por metais pesados, observar, além do teor total, outros parâmetros, como a sua disponibilidade para plantas. No experimento em casa de vegetação, as correlações entre o Cd disponível do solo e o Cd acumulado pelas plantas foram significativas somente para a rúcula. O extrator mais eficiente em determinar a fitodisponibilidade de Cd, analisado por meio do Valor L e Razão L, foi o extrator Ácidos Orgânicos / The environmental contamination is increasing worldwide, with large areas affected by heavy metals at concentrations which may pose environmental hazard. Due to industrial activity and highly technical agriculture, it is important to monitor heavy metals levels in soils, since vegetables behave as transfer mechanism of contaminants from soils to higher levels of the food chain. Ingestion of vegetables containing high concentrations of heavy metals is one of the main ways in which these elements enter the human body. Once in human body, heavy metals are deposited in the bone and fat tissues, overlapping noble minerals. Slowly released into the body, heavy metals may cause an array of diseases. The project was divided into three stages, each one with a specific objective: 1st) to determine the concentrations of cadmium, nickel, lead, cobalt and chromium in the most frequently consumed foodstuff in the São Paulo State, Brazil and to compare the heavy metal contents with the permissible limits established by the Brazilian legislation; to calculate intake of heavy metals in human diets for estimating the risk to human health; and to identify crops with the greatest potential for translocation of cadmium into food chain 2nd) to evaluate the cadmium content in leafy vegetables and soils at crop fields 3th) evaluate the phytoavailability of cadmium for leafy vegetables with aid of chemical extractants and radioactive tracer technique (109Cd). The vegetable samples were collected at São Paulo General Warehousing and Centers Company, and heavy metal content was determined by atomic absorption spectrophotometry. All vegetables sampled presented average concentrations of Cd and Ni lower than the permissible limits established by the Brazilian legislation. Exception for Pb and Cr in that 44% of the samples exceeded the maximum permitted limits. The Brazilian legislation has not established a permissible limit for Co contents. Regarding the consumption habit of the population in the São Paulo State, the daily ingestion of heavy metals is below the oral dose of reference, therefore, the consumption of these vegetables can be considered safe and without risk to human health. Leafy vegetables were those most accumulated Cd. Some regions of São Paulo State showed total contents of Cd in soil higher than intervention value established by CETESB. However, the vegetables grown in these areas showed Cd concentrations lower than Brazilian limit established by ANVISA. It is important, when studying environmental contamination by heavy metals, to observe, beside their total content, other parameters, like soil availability. In the greenhouse experiment, the correlation between soil available Cd and plants accumulated Cd were significant only for rocket. The most efficient chemical extractant in determining Cd phytoavailability, analyzed by L Value and L Ratio, were Organic Acids

科学研究費補助金 研究種目:基盤研究(B)(2) 課題番号:10044148 研究代表者:飯田 孝夫 研究期間:1998-1999年度