Low Levels Of Manganese Research Articles

Comparison of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers in bald eagle (Haliaeetus leucocephalus), and comparison with common eider (Somateria mollissima), glaucous-winged gull (Larus glaucescens), pigeon guillemot (Cepphus columba), and tufted puffin (Fratercula cirrhata) from the Aleutian Chain of Alaska

There is an abundance of field data for levels of metals from a range of places, but relatively few from the North Pacific Ocean and Bering Sea. In this paper we examine the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in feathers from common eiders (Somateria mollissima), glaucous-winged gulls (Larus glaucescens), pigeon guillemots (Cepphus columba), tufted puffins (Fratercula cirrhata) and bald eagles (Haliaeetus leucocephalus) from the Aleutian Chain of Alaska. Our primary objective was to test the hypothesis that there are no trophic levels relationships for arsenic, cadmium, chromium, lead, manganese, mercury and selenium among these five species of birds breeding in the marine environment of the Aleutians. There were significant interspecific differences in all metal levels. As predicted bald eagles had the highest levels of arsenic, chromium, lead, and manganese, but puffins had the highest levels of selenium, and pigeon guillemot had higher levels of mercury than eagles (although the differences were not significant). Common eiders, at the lowest trophic level had the lowest levels of some metals (chromium, mercury and selenium). However, eiders had higher levels than all other species (except eagles) for arsenic, cadmium, lead, and manganese. Levels of lead were higher in breast than in wing feathers of bald eagles. Except for lead, there were no significant differences in metal levels in feathers of bald eagles nesting on Adak and Amchitka Island; lead was higher on Adak than Amchitka. Eagle chicks tended to have lower levels of manganese than older eagles.

アルコールと脳内微量元素

When men drink excessive amounts of alcohol over a prolonged period, they may develop neurological diseases, such as peripheral neuropathy, Wernicke encephalopathy, and alcohol-induced cerebellar degeneration. Trace elements in the brain can lead to the increased expression of receptors, enzymes for the synthesis and metabolism of the neurotransmitter, and proteins that modulate function, ets. It is possible that various neurological symptoms occur when trace elements in the brain are affected by excessive consumption of alcohol, even though the trace elements in the brain are maintained at a constant level. Drinking excessive levels of alcohol increases the level of zinc in the brain, while lower levels of zinc in blood are seen in men with signs of chronic excessive alcohol consumption, such as with alcoholic cirrhosis. It is speculated that increased free radicals by acute alcoholic intake, cause zinc to be increased in the brain in response to this phenomenon. Copper is closely related to neurological diseases, such as Wilson′s disease or Menkes disease, but there have been no reports regarding encephalopathy induced by changes in copper and its metabolites in the brain due to drinking. About 80% of manganese in the brain exists within the astrocytes, and is involved in glutamine metabolism. However, there have not been many reports concerning the relation between alcohol and manganese. Low levels of manganese in the blood are observed in chronic alcoholics and these patients exhibit delirium tremens, tetany, convulsions, athetosis and involuntary movement. The level of iron in the blood increases with chronic excessive alcohol drinking, but there have been no reports indicating that iron levels in the brain are modified by alcohol intake. Metal-lothionein (MT) contributes significantly to zinc and copper metabolism and functions as a protective protein, but MT in the brain is increased when the MT-I overexpressing transgenic mouse (MT-I*) is administered 4 g/kg of ethanol by a gastric tube. Acute ethanol administration can generate oxygen free radicals and cause oxidative stress in the brain. The mechanism of induction of MT in the brain after oral ethanol administration may be associated with oxidative stress caused by ethanol or its metabolites, and can be considered a protective mechanism against ethanol toxicity.

Manganese-enhanced magnetic resonance microscopy of mineralization

Paramagnetic manganese (II) can be employed as a calcium surrogate to sensitize magnetic resonance microscopy (MRM) to the processing of calcium during bone formation. At high doses, osteoblasts can take up sufficient quantities of manganese, resulting in marked changes in water proton T(1), T(2) and magnetization transfer ratio values compared to those for untreated cells. Accordingly, inductively coupled plasma mass spectrometry (ICP-MS) results confirm that the manganese content of treated cell pellets was 10-fold higher than that for untreated cell pellets. To establish that manganese is processed like calcium and deposited as bone, calvaria from the skull of embryonic chicks were grown in culture medium supplemented with 1 mM MnCl(2) and 3 mM CaCl(2). A banding pattern of high and low T(2) values, consistent with mineral deposits with high and low levels of manganese, was observed radiating from the calvarial ridge. The results of ICP-MS studies confirm that manganese-treated calvaria take up increasing amounts of manganese with time in culture. Finally, elemental mapping studies with electron probe microanalysis confirmed local variations in the manganese content of bone newly deposited on the calvarial surface. This is the first reported use of manganese-enhanced MRM to study the process whereby calcium is taken up by osteoblasts cells and deposited as bone.

Effect of Manganese Addition on Reactive Evaporation of Chromium in Ni-Cr Alloys

Chromium is used as an alloy addition in stainless steels and nickel-chromium alloys to form protective chromium oxide scales. Chromium oxide undergoes reactive evaporation in high-temperature exposures in the presence of oxygen and/or water vapor. Deposition of gaseous chromium species onto solid oxide fuel-cell electrodes can reduce the efficiency of the fuel cell. Manganese additions to the alloy can reduce the activity of chromium in the oxide, either from solid solution replacement of chromium with manganese (at low levels of manganese) or from the formation of manganese-chromium spinels (at high levels of manganese). This reduction in chromium activity leads to a predicted reduction in chromium evaporation factors as much as 35 at 800 °C and 55 at 700 °C. Quantifying the effects of manganese additions on chromium evaporation should aid alloy development of metallic interconnects and balance-of-plant alloys.

Multi-element survey of wild edible fungi and blackberries in the UK

A survey of 12 metals including lead (Pb), copper (Cu), cadmium (Cd), mercury (Hg), arsenic (As) and platinum (Pt) was carried out using ICP-MS in 34 samples of wild fungi and 48 samples of wild blackberries collected from sites across the UK. On a fresh weight basis (mg/kg) levels of Pb were in the range 0.003–5.990, Cu 0.596–34.800, Cd < 0.001–19.6, Hg < 0.001–4.150, As 0.001–0.972 and Pt (µg/kg) 0.006–0.200, with higher concentrations found in fungi than in blackberries. The results of the survey showed that the concentrations of the metals were consistent with previous studies, where available. Concentrations in wild fungi of Pt, tin (Sn), and titanium (Ti) were significantly higher at urban sites than at rural sites. Urban blackberries had significantly higher levels of Pb, Ti, and Cd than rural ones, but lower levels of manganese (Mn). Pb, Ti and Sn concentrations were significantly higher in blackberries sampled near main roads rather than in rural areas.

Quantifying postural tremor in workers exposed to low levels of manganese

The aim of this study was: (1) To determine the minimum number of characteristics necessary to discriminate between postural tremor recorded in control subjects (CO), in subjects exposed to manganese (MN), and in patients with Parkinson’s disease (PD), and (2) to examine the continuum of changes between the three groups examined. Workers previously exposed to Mn ( n = 10), patients with PD ( n = 10), and control subjects (CO) ( n = 11) underwent a clinical examination. Blood Mn was measured at the end of exposure time for the MN group and 12 months later at the beginning of the experiment for all groups. Postural tremor with visual feedback was recorded in the index finger with a laser system. Statistical criteria were used to reduce computed tremor characteristics to a minimal set of reliable discriminating variables. Two variables were retained namely corrected wobble (CW), describing the morphology of the tremor oscillations, and variability ratio (VR), describing proportional power of tremor. Both variables had an overall correct classification rate of 77.4%. Blood Mn levels at the time of the experiment were similar for all groups and had insignificant correlation with tremor variables. However, blood Mn levels in workers which were also measured at the end of exposure time (i.e., 12 months before) showed significant correlation (Spearman’s rank coefficient) with both harmonic index ( ρ = 0.70, P = 0.03) and first maximum of the autocorrelation function ( ρ = 0.89, P = 0.001). We conclude that (1) the tremor of workers exposed to Mn could be adequately described with only two variables; (2) a continuum of changes between tremor recorded in control subjects, in subjects exposed to Mn and in patients with PD was observed, with the MN group always found in between the control (CO) and the PD groups; (3) while blood Mn levels in workers were back at control levels at the time of the experiment, the effect of Mn on postural tremor was still detected. Thus our method has the potential to detect the effect of Mn on tremor with only two variables even after Mn level in the blood is back to normal values.

The Saccharomyces cerevisiae High Affinity Phosphate Transporter Encoded by PHO84 Also Functions in Manganese Homeostasis

In the bakers' yeast Saccharomyces cerevisiae, high affinity manganese uptake and intracellular distribution involve two members of the Nramp family of genes, SMF1 and SMF2. In a search for other genes involved in manganese homeostasis, PHO84 was identified. The PHO84 gene encodes a high affinity inorganic phosphate transporter, and we find that its disruption results in a manganese-resistant phenotype. Resistance to zinc, cobalt, and copper ions was also demonstrated for pho84Delta yeast. When challenged with high concentrations of metals, pho84Delta yeast have reduced metal ion accumulation, suggesting that resistance is due to reduced uptake of metal ions. Pho84p accounted for virtually all the manganese accumulated under metal surplus conditions, demonstrating that this transporter is the major source of excess manganese accumulation. The manganese taken in via Pho84p is indeed biologically active and can not only cause toxicity but can also be incorporated into manganese-requiring enzymes. Pho84p is essential for activating manganese enzymes in smf2Delta mutants that rely on low affinity manganese transport systems. A role for Pho84p in manganese accumulation was also identified in a standard laboratory growth medium when high affinity manganese uptake is active. Under these conditions, cells lacking both Pho84p and the high affinity Smf1p transporter accumulated low levels of manganese, although there was no major effect on activity of manganese-requiring enzymes. We conclude that Pho84p plays a role in manganese homeostasis predominantly under manganese surplus conditions and appears to be functioning as a low affinity metal transporter.

Trace elemental analysis of carcinoma kidney and stomach by PIXE method

Trace elemental analysis was carried out in the biological samples of carcinoma kidney and stomach using particle induced X-ray emission technique. A 2 MeV proton beam was employed to excite the samples. From the present results, the levels of elements K, Ca, Fe, Ni and Se are lower and those of the elements Ti, Co, Zn, As and Cd are higher in the cancer tissue of kidney than those observed in the normal tissue. In the case of stomach, the concentrations of elements Cl, K, Ca, Ti, Mn, Fe, Co, Cu and Zn are lower while concentrations of elements Cr, Ni, As and Br are higher in the cancer tissue of stomach than those observed in the normal tissue. The observed deficiency or excess of certain elements is correlated to carcinogenesis of that organ. The present results of carcinoma stomach support the previous observations that nickel and chromium are carcinogenic agents. The low levels of selenium observed in the carcinoma tissue of kidney and the low levels of manganese observed in the carcinoma tissue of stomach support the view that selenium and manganese inhibit the growth of cancer in kidney and stomach respectively. The observed high levels of zinc in the cancer tissue of kidney suggest that zinc is involved in the tumor growth and development of neoplastic transformation in kidney while the observed low levels of zinc in the carcinoma tissue of stomach suggest that zinc inhibits the growth of cancer in this organ. For correctly assessing the role played by the trace elements in initiating, promoting or inhibiting cancer in various organs, there is a need for acquisition of more data by trace elemental analysis from several investigations of this type undertaken in different regions.

COMPOSTS AS SOIL SUPPLEMENT ENHANCED PLANT GROWTH AND FRUIT QUALITY OF STRAWBERRY

ABSTRACT Compost significantly enhanced strawberry (Fragaria × ananassa Duch.) plant growth and fruit quality when used as a soil supplement. Adding half strength of Peter nutrient solution (50% fertilizer) to a mixture of 50% soil plus 50% compost was very effective in significantly increasing plant dry weight to approximately double that of controls (without compost), fruit yield by more than 70%, and fruit size by 15% compared to controls in the two strawberry cultivars (“Allstar” and “Honeoye”). Compost and fertilizer also significantly enhanced leaf chlorophyll content. Nitrate reductase activity significantly increased in leaves and roots with the greatest increases when using 50% soil plus 50% compost. Strawberry plants grown with compost had significantly higher levels of nitrogen (N) and potassium (K), but lower levels of manganese (Mn), iron (Fe), molybdenum (Mo), and nickel (Ni) in fruit of both “Allstar” and “Honeoye”. Adding compost to the soil mix did not change zinc (Zn) and cadmium (Cd) levels. Use of compost also significantly increased levels of organic acids (malic and citric acid), sugars (fructose, glucose, and total sugars), soluble solids content, and titratable acidity content in both cultivars. The results indicate that the use of compost can reduce the amount of fertilizer required for optimum strawberry plant growth.

Influence of heat treatment and surface conditioning on filiform corrosion of aluminium alloys AA3005 and AA5754

The effect of high-temperature heat treatment combined with different cleaning and pre-treatment practices on filiform corrosion resistance has been investigated for aluminium alloys AA3005 and AA5754. High-temperature heat treatment severely reduces the filiform corrosion resistance of alloy AA3005, while the corrosion properties of alloy 5754 are only moderately affected. The drastic loss of filiform corrosion resistance of alloy AA3005 after high-temperature heat treatment is attributed to preferential microstructural changes in a heavily deformed, micrograined surface layer caused by large surface shear strain during rolling. The enhanced deformation of the near-surface region promotes precipitation of a fine dispersion of intermetallic particles during subsequent heat treatment. The higher density of intermetallic particles combined with lower supersaturated solid solution levels of manganese in the surface layer as compared to the bulk structure makes the heat-treated AA3005 material susceptible to superficial corrosion attacks and results in poor filiform corrosion resistance. Application of a commercial acid cleaning/chromating pre-treatment did not restore the filiform corrosion resistance of heat-treated alloy AA3005. Alloy AA5754, containing lower levels of manganese and iron than AA3005, did not undergo similar preferential microstructural changes during heat treatment. A moderate increase in the amount of filiform corrosion of heat-treated AA5754 samples is attributed to poor protective properties of the thick, magnesium enriched, thermally formed surface oxide on this alloy. Any cleaning/pre-treatment practice that removes the thermally formed oxide on this alloy results in a very high filiform corrosion resistance.

Metal content in insects associated with ultramafic and non‐ultramafic sites in the Scottish Highlands

Summary1. Concentrations of magnesium, manganese, chromium, and cadmium were measured in Coleoptera, Diptera, Hemiptera, and Hymenoptera captured at ultramafic and non‐ultramafic sites in the Highlands of Scotland.2. The Hemiptera showed the greatest concentration differences between the ultramafic and non‐ultramafic sites in manganese, magnesium, and chromium, with greatly increased levels in ultramafic sites.3. The Coleoptera and Hymenoptera had lower levels of manganese, magnesium, and chromium at the ultramafic site than at the non‐ultramafic sites. The Diptera had increased levels of manganese and magnesium at the ultramafic site, but showed no difference in chromium levels from any site.4. Cadmium occurred at lower levels in all insect orders at the ultramafic site.

In vivo stimulation-induced release of manganese in rat amygdala

The role of manganese ions in neural functions is poorly understood because of the low level of manganese in the brain. An excess of this ion is associated with neurological disorders such as extrapyramidal symptoms. We demonstrated that manganese may be taken up by piriform neurons (tertiary olfactory neurons) after release from the terminals of secondary olfactory neurons, in which 54 Mn taken up by the soma may be anterogradely transported [A. Takeda, Y. Kodama, S. Ishiwatari, S. Okada, Manganese transport in the neural circuit of Rat CNS, Brain Res. Bull. (45) (1998) 149–152]. Here we demonstrate for the first time that 54 Mn previously taken up into the amygdala is released with neurotransmitters into the extracellular space during stimulation with high K +. The results suggest that the role of manganese ions in the amygdala, and probably in the olfactory system, is dynamically linked to neural signalling processes.

Heavy metal and selenium concentrations in feathers of egrets from Bali and Sulawesi, Indonesia.

Herons and egrets are ideal organisms to use asindicators of heavy metal exposure in an ecosystem because different speciesfeed at different levels of the food chain and live in both coastal andinland habitats. This paper reports on the concentration of heavy metals andselenium in the feathers of cattle egrets Bubulcus ibis that wereexamined from nesting and roosting sites in Bali and Sulawesi, Indonesia, andin feathers of little egrets Egretta garzetta and intermediate egretsE. intermedia from the same colony in Bali. Mercury and manganeseconcentrations were significantly higher in cattle egrets from Bali comparedto Sulawesi, but otherwise there were no significant differences. There weresignificant differences in lead, cadmium and mercury among the three egretspecies nesting on Bali: 1) the cadmium and mercury concentrations related tosize and trophic level (insectivorous cattle egrets had the lowestconcentrations, fish-eating intermediate egrets had the highestconcentrations), and 2) cattle egrets had significantly lower concentrationsof lead than the other two species. For cattle egrets, secondary flightfeathers had significantly higher levels of cadmium and mercury, and lowerlevels of manganese, than mixed breast and tertiary feathers, reflectingtemporal differences in exposure.

Roles of manganese and organic acid chelators in regulating lignin degradation and biosynthesis of peroxidases by Phanerochaete chrysosporium.

We studied the effect of manganese and various organic chelators on the distribution, depolymerization, and mineralization of synthetic 14C-labeled lignins (DHP) in cultures of Phanerochaete chrysosporium. In the presence of high levels of manganese [Mn(II) or Mn(III)], along with a suitable chelator, lignin peroxidase (LiP) production was repressed and manganese peroxidase (MnP) production was stimulated. Even though partial lignin depolymerization was observed under these conditions, further depolymerization of the polymer to smaller compounds was more efficient when low levels of manganese were present. LiPs were prevalent under these latter conditions, but MnPs were also present. Mineralization was more efficient with low manganese. These studies indicate that MnP performs the initial steps of DHP depolymerization but that LiP is necessary for further degradation of the polymer to lower-molecular-weight products and mineralization. We also conclude that a soluble Mn(II)-Mn(III) organic acid complex is necessary to repress LiP.

The photochemistry of manganese and the origin of banded iron formations

The photochemical oxidation of Fe 2+ -hydroxide complexes dissolved in anoxic Precambrian oceans has been suggested as a mechanism to explain the deposition of Banded Iron Formations (BIFs). Photochemical studies have not yet addressed the low levels of manganese in many of these deposits, which probably precipitated from solutions bearing similar concentrations of Fe 2+ and Mn 2+. Depositional models must also explain the stratigraphie separation of iron and manganese ores in manganiferous BIFs. In this study, solutions containing 0.56 M NaCl and ≈ 180 μM MnCl 2 with or without 3 to 200 μM FeCl 2 were irradiated with filtered and unfiltered UV light from a medium-pressure mercury-vapor lamp for up to 8 hours. The solutions were deaerated and buffered to pH ≈ 7, and all experiments were conducted under O 2-free (< 1 ppm) atmospheres. In experiments with NaCl + MnCl 2, approximately 20% of the Mn 2+ was oxidized and precipitated as birnessite in 8 hours. Manganese precipitation was only observed when light with λ < 240 nm was used. In experiments with NaCl + MnCl 2 + FeCl 2, little manganese was lost from solution, while Fe 2+ was rapidly oxidized to Fe 3+ and precipitated as γ-FeOOH or as amorphous ferric hydroxide. The Mn:Fe ratio of these precipitates was ≈ 1:50, similar to the ratios observed in BIFs. A strong upper limit on the rate of manganese photo-oxidation during the Precambrian is estimated to be 0.1 mg cm −2 yr −1, a factor of 10 3 slower than the rate of iron photo-oxidation considered reasonable in BIF depositional basins. Thus, a photochemical model for the origin of oxide facies BIFs is consistent with field observations, although models that invoke molecular O 2 as the oxidant of Fe 2+ and Mn 2+ are not precluded. Apparently, oxide facies BIFs could have formed under anoxic, as well as under mildly oxygenated atmospheres.

Chondrodystrophy in calves associated with manganese deficiency

A severe congenital chondrodystrophy in Charolais calves is described. Thirty-two calves were born on the same farm with shortened limbs and enlarged joints. Histologically, there was poor cartilage maturation with excessive amounts of rarefied cartilage matrix. There were degenerative changes in the chondrocytes and a severe reduction in the mucopolysaccharide content of all body hyaline cartilage. The cartilage matrix, when examined ultrastructurally, showed loose, disorganised fibres in a rarefied matrix, and extensive vacuolation of the chondrocytes. A low level of manganese was found in the liver of an affected calf. The pregnant cows were fed on apple pulp and corn silage, both of which are low in manganese.

Psychological test performance in foundry workers exposed to low levels of manganese

A sample of 30 manganese-exposed foundry workers from two Swedish plants were examined with a partly computerized psychological test battery, comprised of 10 performance tests. Performance of the manganese-exposed workers was compared to that of a matched control group of 60 workers. Matching criteria were age, geographical area, type of work, and the results on a test of verbal comprehension. Performance of the exposed workers was inferior to that of the control group on tests of simple reaction time, digit span, and finger tapping. No correlations were found between performance and the present manganese exposure levels or the number of years employed in manganese work. The results seem to indicate that the present exposure standards for manganese, in Sweden 2.5 mg/m 3 and in most other countries 5 mg/m 3, are not sufficient to protect workers from negative effects on performance capacity.

Trace elements in hair in the UK: Results and interpretation in the preconception situation

The paper examines the high incidence of birth defects that still occur in the UK and suggests that it might be possible to reduce this by preparing prospective mothers for parenthood prior to conception. One test in particular is suggested as having a part to play in this preconception screening — that being the hair metals analysis. Such a screening test is useful in identifying both excesses of toxic metals and deficiencies of essential metals. The results from our studies seem to indicate a high proportion of potential mothers as having low levels of manganese, iron and possibly zinc in their hair. The significance of these findings is discussed in relation to the possible effect on birth defects and the possible routine use of hair metal testing in the pre-conception situation is suggested.

The effect of dietary ascorbate, zinc, and manganese on the development of experimentally induced bacterial kidney disease in sockeye salmon ( Oncorhynchus nerka)

Seven groups of juvenile sockeye salmon ( Oncorhynchus nerka) were each reared on a different test diet to determine the influence of nutritional status on their resistance to experimentally induced bacterial kidney disease (BKD). Six test diets were formulated so that the prophylactic efficacy of two levels of vitamin C (supplied as Na L-ascorbate-2-sulfate) in combination with low levels of manganese (Mn) without zinc (Zn) and high levels of Mn with Zn supplement could be evaluated. The Oregon Moist Pellet diet served as a reference standard. Mortality curves were clearly distinct and mean survival times were significantly different (P<0.05) for each of three dosages of R. salmoninarum inoculated, irrespective of diet. Survival time was found to be inversely related to dietary ascorbate level at each dosage of the bacterium but only when diets contained low levels of Zn and Mn. None of the dietary variations exerted a significant effect on the production of serum antibodies against an injected bacterial vaccine. Seawater challenge and injections of Prednisolone acetate failed to initiate an outbreak of BKD in any of the uninoculated dietary stocks where, historically, naturally infected fish might have been expected.

Comparative response of poppy (Papaver somniferumL.) and eight crop and vegetable species to manganese excess in solution culture

Abstract The relative response of poppy (Papaver somniferum L.) and eight crop and vegetable species to excess manganese was investigated in a glasshouse, solution culture experiment. Plant yields and manganese concentrations were measured after two and six weeks growth at five levels of manganese (10–800 μM). Poppies were highly sensitive to manganese toxicity in solution culture and reductions in shoot yield occurred at lower manganese levels in solution and at lower shoot manganese concentrations than that for the following sensitive species, ranked in order of increasing tolerance : brussels sprout, barley, green beans, lucerne and grean pea. In contrast lupins, oats and sugar beet were relatively tolerant producing about 80% or more of maximum shoot yield at the highest solution manganese level (800 μM Mn). In this study the sensitivity of poppy, and brussels sprout, to manganese excess was attributed to their low shoot manganese “toxicity threshold values”; and their capacity to partition a high proportion of total plant manganese and dry matter to the shoot at solution manganese levels ≥ 100 μM. The application of these results to field grown poppy is discussed in relation to interactions between manganese and other elements which modify plant tolerance to manganese excess.