Zinc, iron, and copper absorption in the streptozotocin-diabetic rat

1983 ◽  
Vol 244 (2) ◽  
pp. E122-E128 ◽  
Author(s):  
N. E. Craft ◽  
M. L. Failla
Keyword(s):  
Trace Metals ◽  
Trace Metal ◽  
Brush Border ◽  
Initial Rate ◽  
Diabetic Rat ◽  
Metal Absorption ◽  
Mucosal Mass ◽  
Streptozotocin Diabetic Rat ◽  
Cu And Zn

Altered tissue levels of trace metals have been reported in streptozotocin-diabetic (STZ) rats. To determine whether increased hepatic and renal levels of Cu and Zn were associated with enhanced intestinal absorption, trace metal absorption was studied in control (C) and STZ rats using dietary balance and in situ ligated-loop techniques. The apparent daily absorption of dietary Zn and Cu per 100 g body wt was threefold higher in STZ than C rats. In comparison, dietary Fe absorption per day was not altered. Increased Zn absorption was closely correlated with diabetes-associated polyphagia. The initial rate of injected 65Zn excretion was more rapid in STZ rats, although the rate of excretion beyond day 7 was similar from C and STZ animals. The quantity of Zn, Fe, and Cu absorbed per 20 cm duodenal loop was similar for C and STZ rats. Zn, Fe, and Cu absorption per gram dry mucosa were reduced 45-53% in STZ rats due to the 50% increase in mucosal mass. Moreover, the quantity of radioisotopes accumulated per gram dry mucosa and the concentration of metallothionein per gram mucosal cytosol protein were similar in C and STZ animals. Together, these data demonstrate that increased absorption of dietary Zn and Cu is in part responsible for accumulation of these elements in STZ tissues and suggest altered metal transport at the luminal (brush border) surface of the intestinal epithelium.

scholarly journals Spatial Assessment of Anthropogenic Impact on Trace Metal Accumulation in Farmland Soils from a Rapid Industrializing Region, East China

2018 ◽  
Vol 15 (9) ◽  
pp. 2052 ◽  
Author(s):  
Wei Jiao ◽  
Yong Niu ◽  
Yuan Niu ◽  
Hengyu Hu ◽  
Ruiping Li
Keyword(s):  
Trace Metals ◽  
Trace Metal ◽  
Anthropogenic Impact ◽  
Metal Accumulation ◽  
Geographical Information ◽  
Anthropogenic Sources ◽  
East China ◽  
Spatial Assessment ◽  
Farmland Soils ◽  
Cu And Zn

A better understanding of anthropogenic trace metal accumulation in farmland soils is crucial for local food safety and public health, especially for a rapidly industrializing region. In this study, soil samples at two depths were collected from a typical county in East China and analyzed for total concentrations of Fe, Al, Pb, Cd, Cu, Zn, Cr, and Ni. Results showed that trace metals like Pb, Cd, Cu, Zn, Cr, and Ni have accumulated in the regional farmlands, with average topsoil concentrations 1.62–1.77 times higher than their background concentrations in subsoil. However, they were still much lower than the limits of the Chinese Environmental Quality Standard for Soils. By the proper calculation of enrichment factor (EF), it was found that the accumulations of trace metals in the topsoil have been impacted by anthropogenic activities, which could contribute up to 40.83% of total metal concentration. Two principal components were extracted according to the results of principal component analysis (PCA) for EF values, which indicated two important anthropogenic trace metal sources. With the help of spatial distribution maps based on geographical information system (GIS), the anthropogenic sources of Pb, Cr, and Ni were determined to be mostly associated with atmospheric deposition from the central urban area. However, Cd, Cu, and Zn were further confirmed to originate from different agricultural sources. The anthropogenic Cu and Zn inputs were mostly related to pig manure application in the rural northern and southeastern areas, while extensive fertilizer application was identified as the major contributor to anthropogenic Cd accumulation in this region. Overall, the integrated application of EF, PCA, and GIS mapping is an effective approach to achieve the spatial assessment of anthropogenic impact on trace metal accumulation in regional soils.

Assessment of heavy metals in tobacco of cigarettes commonly sold in Ethiopia

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Heavy Metals ◽  
Trace Metals ◽  
Atomic Absorption Spectrophotometry ◽  
Epidemiological Studies ◽  
Cigarette Tobacco ◽  
Absorption Spectrophotometry ◽  
Wet Digestion ◽  
Metal Contents ◽  
Cu And Zn ◽  
Significant Flux

A significant flux of heavy metals, among other toxins, reaches the lungs through smoking. This study reports Cd, Pb, Cu and Zn contents in tobacco of 11 brands of cigarette commonly sold in Ethiopia. The heavy metals were determined by atomic absorption spectrophotometry after wet digestion of cigarette tobacco using HNO3 and H2O2. The concentration of trace metals in the cigarettes ranged (mean) (μg/g), Cd: 1.3−7.6 (2.48±0.32), Pb: 0.50−12.50 (6.24±2.2), Cu: 2.89−25.35 (13.70±4.12) and Zn: 24.40−62.55 (36.22±7.50) while Ni was not detected in all the eleven brands of cigarettes. Comparable levels of trace metals were obtained in the tobacco of both imported and Ethiopian cigarettes. The average trace metal contents of cigarettes available in Ethiopia were Cd 1.82±0.39, Pb 4.23±0.97, Cu 10.2±3.1 and Zn 28.2±7.8 μg/cigarette and a person who smokes 20 cigarettes per day is estimated to increase his/her daily Cd, Pb, Cu and Zn retention by approximately 0.036, 0.085, 0.204, 0.564 mg/day, respectively. The results indicate that smoking and exposure to cigarette smoke is a serious problem to be taken into account when carrying out epidemiological studies on human exposure to trace metals.

Polyol pathway activity in streptozotocin-diabetic rat lens

1989 ◽  
Vol 49 (1) ◽  
pp. 87-92 ◽  
Author(s):  
Hong-Ming Cheng ◽  
Keiko Hirose ◽  
Hua Xiong ◽  
R.Gilberto González
Keyword(s):  
Polyol Pathway ◽  
Diabetic Rat ◽  
Pathway Activity ◽  
Streptozotocin Diabetic Rat

scholarly journals Marine ammonia-oxidising archaea and bacteria occupy distinct iron and copper niches

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Roxana T. Shafiee ◽  
Poppy J. Diver ◽  
Joseph T. Snow ◽  
Qiong Zhang ◽  
Rosalind E. M. Rickaby
Keyword(s):  
Comparative Genomics ◽  
Trace Metals ◽  
Trace Metal ◽  
Ammonia Oxidation ◽  
Testable Hypothesis ◽  
Niche Separation ◽  
Toxicity Threshold ◽  
Geologic Time ◽  
Additional Explanation ◽  
Ammonia Oxidising Archaea

AbstractAmmonia oxidation by archaea and bacteria (AOA and AOB), is the first step of nitrification in the oceans. As AOA have an ammonium affinity 200-fold higher than AOB isolates, the chemical niche allowing AOB to persist in the oligotrophic ocean remains unclear. Here we show that marine isolates, Nitrosopumilus maritimus strain SCM1 (AOA) and Nitrosococcus oceani strain C-107 (AOB) have contrasting physiologies in response to the trace metals iron (Fe) and copper (Cu), holding potential implications for their niche separation in the oceans. A greater affinity for unchelated Fe may allow AOB to inhabit shallower, euphotic waters where ammonium supply is high, but competition for Fe is rife. In contrast to AOB, AOA isolates have a greater affinity and toxicity threshold for unchelated Cu providing additional explanation to the greater success of AOA in the marine environment where Cu availability can be highly variable. Using comparative genomics, we predict that the proteomic and metal transport basis giving rise to contrasting physiologies in isolates is widespread across phylogenetically diverse marine AOA and AOB that are not yet available in pure culture. Our results develop the testable hypothesis that ammonia oxidation may be limited by Cu in large tracts of the open ocean and suggest a relatively earlier emergence of AOB than AOA when considered in the context of evolving trace metal availabilities over geologic time.

scholarly journals Microwave Sensors for In Situ Monitoring of Trace Metals in Polluted Water

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3147
Author(s):  
Ilaria Frau ◽  
Stephen Wylie ◽  
Patrick Byrne ◽  
Patrizia Onnis ◽  
Jeff Cullen ◽  
...  
Keyword(s):  
Trace Metals ◽  
In Situ Monitoring ◽  
Polluted Water ◽  
Pollution Level ◽  
Mining Areas ◽  
Low Concentrations ◽  
The Uk ◽  
Microwave Sensors ◽  
Immediate Response

Thousands of pollutants are threatening our water supply, putting at risk human and environmental health. Between them, trace metals are of significant concern, due to their high toxicity at low concentrations. Abandoned mining areas are globally one of the major sources of toxic metals. Nowadays, no method can guarantee an immediate response for quantifying these pollutants. In this work, a novel technique based on microwave spectroscopy and planar sensors for in situ real-time monitoring of water quality is described. The sensors were developed to directly probe water samples, and in situ trial measurements were performed in freshwater in four polluted mining areas in the UK. Planar microwave sensors were able detect the water pollution level with an immediate response specifically depicted at three resonant peaks in the GHz range. To the authors’ best knowledge, this is the first time that planar microwave sensors were tested in situ, demonstrating the ability to use this method for classifying more and less polluted water using a multiple-peak approach.

scholarly journals Significance of building and plumbing specifics on trace metal concentrations in drinking water

1991 ◽  
Vol 18 (6) ◽  
pp. 893-903 ◽  
Author(s):  
Inderjit Singh ◽  
Donald S. Mavinic
Keyword(s):  
Drinking Water ◽  
Trace Metals ◽  
Trace Metal ◽  
Water Samples ◽  
First Flush ◽  
Single Family ◽  
Metal Concentrations ◽  
Building Height ◽  
High Rise ◽  
Family House

Samples were taken from 72 high-rise apartment suites (6 suites in 12 individual high-rise towers) and 60 single-family houses located within the Greater Vancouver Regional District. The influence of the following factors on trace metal concentrations in 1-L first-flush drinking water samples and “running” hot water samples was investigated: building height, location, plumbing age, type of plumbing, and type of building. Results of this survey show that with the exception of building height, all factors had a correlation with one or more of the trace metals investigated. The trace metals examined were lead, copper, iron, and zinc. Lead was influenced primarily by building type, copper by plumbing age and type of plumbing, and iron by location. Elevated lead levels were associated with high-rise samples. New copper plumbing systems resulted in high copper levels. Highest iron levels in the drinking water were measured in the East Vancouver location. Zinc did not show a distinct correlation with any of the factors investigated. Brass faucets were the primary source of zinc in tap water. They also contributed substantially to the lead detected in the 1-L first-flush sample. Metal concentrations measured in the high-rise and house samples were compared with the U.S. Environmental Protection Agency's (USEPA) maximum contaminant levels (MCLs) and the proposed “no-action” level for lead. In high-rise samples, the 0.01 mg/L “no-action” level proposed for lead was exceeded in 43% of the samples, and 62% of the samples exceeded the current 1.0 mg/L MCL standard for copper. In single-family house samples, these values were 47% and 73%, respectively. The average lead concentrations were 0.020 mg/L for all high-rise samples and 0.013 mg/L for house samples. Regulatory levels stated above would still be exceeded in 6% of the cases for lead and 9% of the cases for copper, even after prolonged flushing of the tap in a high-rise building. In all cases associated with single-family houses, flushing the cold water tap for 5 minutes was successful in achieving compliance levels. Key words: aggressive water, compliance, corrosive, drinking water, first-flush, GVRD, high-rise, single-family house, trace metals, USEPA.

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