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1

Strategies to increase selectivity of analytical methods for As, Cr and Se speciation in biological samples: A review

100%

Carvalho D. C., Coelho N. M. M., Melo Coelho L., Borges S. S. S., Neri T. S., Alves V. N.

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issue 1

EN

This review provides an overview and discusses different analytical strategies that minimize or eliminate the preparation of samples for speciation of organic and inorganic species of As, Cr and Se in samples of biological interest. These metals are important for the human body and the presence of various chemical forms of metals determines its essentiality and toxicity, thus speciation comes as an important tool for the study of biological samples. However, speciation requires a reduction in the steps of sample preparation, allowing a sample investigation in its most native form in order to reduce the changes in chemical species. The strategies proposed for speciation of these metals include: solid phase extraction, point cloud extraction, suspension and direct analysis. Selected methods proposed for the speciation of organic and inorganic species of As, Cr and Se were reviewed including their main figures of merit, advantages and disadvantages

2

Developing New Routine for Processing Two-Dimensional Coincidence Doppler Energy Spectra and Evaluation of Electron Subsystem Properties in Metals

100%

Stepanov P., Stepanov S., Byakov V., Selim F.

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2017

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vol. 132

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issue 5

1628-1633

EN

A digital coincidence Doppler broadening (CDB) spectrometer consisting of two HPGe detectors is assembled; the energy resolution of each detector is 1.1 keV at energies near the annihilation line. Two desktop applications for CDB spectra processing are developed. TLIST Processor converts two-dimensional CDB spectra into one-dimensional spectra. Another tool SW Calculator deconvolutes the experimental CDB spectra into contributions from positron annihilation with valence, core and conduction band electrons. The program estimates the energies of the corresponding electrons and evaluates S and W parameters of the CDB spectra.

3

Toxicological and cytophysiological aspects of lanthanides action.

88%

Pałasz A., Czekaj P.

Acta Biochimica Polonica

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2000

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vol. 47

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issue 4

1107-1114

EN

Lanthanides, also called rare-earth elements, are an interesting group of 15 chemically active, mainly trivalent, f-electronic, silvery-white metals. In fact, lanthanides are not as rare as the name implies, except for promethium, a radioactive artificial element not found in nature. The mean concentrations of lanthanides in the earth's crust are comparable to those of life-important elements like iodine, cobalt and selenium. Many lanthanide compounds show particular magnetic, catalytic and optic properties, and that is why their technical applications are so extensive. Numerous industrial sources enable lanthanides to penetrate into the human body and therefore detailed toxicological studies of these metals are necessary. In the liver, gadolinium selectively inhibits secretion by Kupffer cells and it decreases cytochrome P450 activity in hepatocytes, thereby protecting liver cells against toxic products of xenobiotic biotransformation. Praseodymium ion (Pr3+) produces the same protective effect in liver tissue cultures. Cytophysiological effects of lanthanides appear to result from the similarity of their cationic radii to the size of Ca2+ ions. Trivalent lanthanide ions, especially La3+ and Gd3+, block different calcium channels in human and animal cells. Lanthanides can affect numerous enzymes: Dy3+ and La3+ block Ca2+-ATPase and Mg2+-ATPase, while Eu3+ and Tb3+ inhibit calcineurin. In neurons, lanthanide ions regulate the transport and release of synaptic transmitters and block some membrane receptors, e.g. GABA and glutamate receptors. It is likely that lanthanides significantly and uniquely affect biochemical pathways, thus altering physiological processes in the tissues of humans and animals.

4

Workers’ dermal and total exposure to metals in biomass-fired power plants

88%

Jumpponen M., Heikkinen P., Rönkkömäki H., Laitinen J.

Biomonitoring

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2015

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vol. 2

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issue 1

EN

The aim of this study was to measure ash removal and maintenance workers’ exposure to metals, and assess the suitability of different methods to evaluate metal exposure during these work tasks. Whole-body samples and hand-washing method were used in workers’ dermal exposure assessment, and biomonitoring methods of metals in total exposure assessment. The greatest levels of Al, Pb, Cd, Cu, S, and Zn on workers’ hands were measured in recycled fuel-fired power plants. The median concentrations of lead on workers’ whole-body samples were 4.5 ng/cm2, 17.0 ng/cm2, 11.3 ng/cm2, and 58.4 ng/cm2 in pellet-, peat-, wood- and recycled fuel-fired power plants, respectively. In recycled fuel-fired power plants, workers’ excretions of Al, Pb, and Mn exceeded the reference values of non-exposed population in 33%, 100%, and 50% of samples, respectively. The dermal exposure results clearly showed that power plant ash can significantly contaminate workers’ hands and bodies. The fact that the workers’ urinary excretions of metals exceeded the reference values proved intake of metals during these work tasks. Biomonitoring methods take into account exposures from different sources and, due to that, they are the most recommended approach for estimating the total metal exposure of workers. Hand-washing and whole body sampling were the most recommendable methods for assessing the protection efficiency of gloves and coveralls.

5

The krill chitin and some aspects of metals transport in Antarctic sea-water

88%

Neugebauer W., Bykowski P., Neugebauer E., Neugebauer W., Bykowski P., Neugebauer E.

Polish Polar Research

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1986

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vol. 7

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issue 4

6

Leaching of metals from asbestos-containing products used for roofing

75%

Klojzy-Karczmarczyk B., Mazurek J., Staszczak J., Klojzy-Karczmarczyk B., Mazurek J., Staszczak J.

Gospodarka Surowcami Mineralnymi

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2021

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vol. 37

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issue 3

7

Determination of Total Phenolic Content and Some Selected Metals in Extracts of Moringa oleifera, Cassia tora, Ocimum gratissimum, Vernonia baldwinii and Telfairia occidentalis Plant Leaves

75%

Louis H., Maitera O. N., Boro G., Barminas J. T.

World News of Natural Sciences

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2017

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vol. 11

11-18

EN

The main objective of this research is to determine the content of metals (Ca, Cu, Fe, Mg and Zn) and total phenols in different plant extracts of Moringa oleifera, Cassia tora, Ocimum gratissimum, Vernonia baldwinii and Telfairia occidentalis. Content were determined using Atomic Absorption Spectroscopy. The result indicate that Moringa oleifera plant extracts range from 0.25 ±0.00 to 6.13 ±0.30 mg/kg, Cassia tora plant extracts - 0.17 ±0.03 to 7.48 ±0.06 mg/kg, Ocimum gratissimum plant extracts - 0.18 ±0.00 to 5.43 ±0.12 mg/kg, Vernonia baldwinii and Telfairia occidentalis plant extracts - 0.21 ±0.03 to 7.86 ±0.12 mg/kg and 0.17 ±0.00 to 4.52 ±0.06 mg/kg, respectively. The results also revealed a lower abundance of heavy metals. The total phenolic content was determined using the modified Folin-Ciocalteu method. Herein, the phenolic content in Moringa oleifera was 8.50 ±1.23 mg Garlic Acid Equivalent g-1 (mg GAE g-1), Cassia tora - 30.00 ±0.00 mg GAE g-1, Ocimum gratissimum - 45.00 ±1.41 mg GAE g-1 , Vernonia baldwinii - 49.00 ±1.14 mg GAE g-1 and Telfairia occidentalis - 46.6 7 ±0.27 mg GAE g-1. We found the lowest total phenol content in Moringa oleifera. This also possessed high chelating activity. In contrast, Vernonia baldwinii contained the highest total phenol content, but had low chelating activity. The plant extracts with high levels of phenolic compounds exhibited good antioxidant activity.

8

Forms of occurrence of selected metals in metallurgical slags in comparison with their geochemical properties

75%

Jonczy I., Jonczy I.

Gospodarka Surowcami Mineralnymi

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2012

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vol. 28

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issue 1

9

Exploring the potential of 3-nitrobenzaldehyde thiosemicarbazone: versatile ligand for coordination complexes and its multidisciplinary applications – a review

75%

Senthilkumar V., Nisha S., Saravanan M.

World News of Natural Sciences

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2023

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vol. 50

98-109

EN

3-Nitrobenzaldehyde thiosemicarbazone demonstrates a versatile nature in forming coordination complexes with various metals. These complexes have garnered significant interest in fields such as coordination chemistry, medicinal chemistry, catalysis, and material science. The ligand's nitrogen and sulfur atoms serve as potential coordination sites, allowing for the formation of diverse complexes with different metals. These complexes exhibit bioactive properties in medicinal chemistry, serve as catalysts in catalytic processes, and contribute to the development of novel materials with tailored functionalities in material science. The exploration of 3-nitrobenzaldehyde thiosemicarbazone complexes with multiple metals offers promising avenues for research and application in various scientific disciplines.

10

Comparison of the bioaccumulation potential of selected metals in the tissues of threeinvertebrate taxa: Cepaea, Lumbricus and Geotrupes

75%

Kowalczyk-Pecka D., Stryjecki R., Czepiel-Mil K.

Teka Komisji Ochrony i Kształtowania Środowiska Przyrodniczego

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2015

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vol. XII

11

Investigation of nickel adsorption onto low Jordanian zeolite dose: efficiency and Langmuir – Freundlich behaviour

63%

Al-Ghazawi Z., Qasaimeh A., Al-Bataina B., Al-Ghazawi Z., Qasaimeh A., Al-Bataina B.

Journal of Water and Land Development

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2021

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issue 50

12

The role of physiologically occurring elements in semen and effect of heavy metals on semen

63%

Chyra-Jach D., Kaletka Z., Kasperczyk A.

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issue 74

1-13

EN

Over the last 40 years, the quality of male semen, including the sperm count, has decreased. There are numerous reasons for this phenomenon, including occupational and environmental exposure to heavy metals such as cadmium, lead, mercury and arsenic. Food contaminated with mycotoxins and pesticides, the influence of industrial chemicals, cigarette smoking and endocrine factors are also of great significance. This paper discusses the problem based on the literature of the last few years on the role of physiologically occurring metals in semen and the effect that heavy metals have on decreasing male fertility.

PL

Na przestrzeni ostatnich 40 lat spadła jakość nasienia męskiego, w tym m.in. liczba plemników. U podstaw tego zjawiska leży wiele przyczyn, wśród których wymienia się ekspozycję zawodową i środowiskową na metale ciężkie, m.in. na kadm, ołów, rtęć i arsen. Duże znaczenie ma również zanieczyszczona mykotoksynami i pestycydami żywność, wpływ chemikaliów przemysłowych, palenie papierosów i czynniki endokrynologiczne. Niniejsza praca stanowi omówienie problemu na podstawie piśmiennictwa z ostatnich kilku lat na temat roli metali fizjologicznie występujących w nasieniu oraz wpływu metali ciężkich na obniżenie płodności męskiej.

13

Short Peptides in Minimalistic Biocatalyst Design

63%

Duncan K. L., Ulijn R. V.

Biocatalysis

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2014

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vol. 1

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issue 1

EN

We review recent developments in the use of short peptides in the design of minimalistic biocatalysts focusing on ester hydrolysis. A number of designed peptide nanostructures are shown to have (modest) catalytic activity. Five features are discussed and illustrated by literature examples, including primary peptide sequence, nanosurfaces/scaffolds, binding pockets, multivalency and the presence of metal ions. Some of these are derived from natural enzymes, but others, such as multivalency of active sites on designed nanofibers, may give rise to new features not found in natural enzymes. Remarkably, it is shown that each of these design features give rise to similar rate enhancements in ester hydrolysis. Overall, there has been significant progress in the development of fundamental understanding of the factors that influence binding and activity in recent years, holding promise for increasingly rational design of peptide based biocatalysts.

Refine search results

Strategies to increase selectivity of analytical methods for As, Cr and Se speciation in biological samples: A review

Developing New Routine for Processing Two-Dimensional Coincidence Doppler Energy Spectra and Evaluation of Electron Subsystem Properties in Metals

Toxicological and cytophysiological aspects of lanthanides action.

Workers’ dermal and total exposure to metals in biomass-fired power plants

The krill chitin and some aspects of metals transport in Antarctic sea-water

Leaching of metals from asbestos-containing products used for roofing

Determination of Total Phenolic Content and Some Selected Metals in Extracts of Moringa oleifera, Cassia tora, Ocimum gratissimum, Vernonia baldwinii and Telfairia occidentalis Plant Leaves

Forms of occurrence of selected metals in metallurgical slags in comparison with their geochemical properties

Exploring the potential of 3-nitrobenzaldehyde thiosemicarbazone: versatile ligand for coordination complexes and its multidisciplinary applications – a review

Comparison of the bioaccumulation potential of selected metals in the tissues of threeinvertebrate taxa: Cepaea, Lumbricus and Geotrupes

Investigation of nickel adsorption onto low Jordanian zeolite dose: efficiency and Langmuir – Freundlich behaviour

The role of physiologically occurring elements in semen and effect of heavy metals on semen

Short Peptides in Minimalistic Biocatalyst Design