Environmental pollution has changed dramatically in recent decades. This is an overview of recent... more Environmental pollution has changed dramatically in recent decades. This is an overview of recent advances in the use and significance of molecular biomarkers in environmental and human health risk assessment. Also, here we focused in aquatic organisms as diagnostic tools for aquatic pollution and ecological risk assessment in ecotoxicological studies. The use of molecular biomarkers in aquatic organisms is very important in order to address the broad spectrum of industrial, agricultural, commercial and domestic chemicals entering the environment and especially the aquatic environment and being taken up into the tissues of aquatic organisms. The biomarkers can act as prognostic tools for increased levels of pollution. Biomarkers can be defined as functional measures of exposure to chemical and physical pollutants at the sub-organismal, physiological and behavioural level. This encompasses molecular, cellular, genetic, immunological and physiological measures. The process of ecologic...
Pesticides are mostly synthetic chemicals that are used in agriculture to control pests. Pesticid... more Pesticides are mostly synthetic chemicals that are used in agriculture to control pests. Pesticides include herbicides, insecticides, fungicides, nematocides and rodenticides. The dramatic increase of global use of pesticides in the 1960 and 1970s was the result of growing population and the need for increased food production. Worldwide sales of pesticides increased from $2.7 billion in 1970 to $32,5 billion in 2001. Insecticides account for 1/3 of the world agrochemical market. Mechanization, monoculture, excessive use of fertilizers and pesticides lead to environmental pollution. Soil desertification, wildlife deaths, reduced biodiversity and excessive use of freshwater resources were some of the results. A number of pesticides were highly poisonous and many farmers developed chronic diseases, 30% of intentional suicides in developing countries were caused by toxic pesticides. In recent decades many persistent pesticides were banned or restricted, especially organochlorinated and ...
The complexes of 2-aminomethyl benzimidazole, 2-(beta-aminoethyl)benzimidazole, and 2-(alpha-amin... more The complexes of 2-aminomethyl benzimidazole, 2-(beta-aminoethyl)benzimidazole, and 2-(alpha-aminoethy-l)benzimidazole with Pt(II) and Pd(II) have been prepared. The molecular structure of the free ligands and their complexes were studied by IR and 1H NMR. It was concluded that the substituted benzimidazole derivatives behave as bidentate ligands, being bound to the metal atoms via the nitrogen of the -N = group and the amino group of the side chain of the benzimidazole ring. The metal complexes were tested for antineoplastic activity both in cultures of neoplastic cells (MEL-745, K-562, Colon 205, IMP-32, SK-N-SH) and in vivo in rodents bearing L-1210 leukemia. The antiproliferative activity of these agents was compared to that of cis-platin.
... The role of iron ions. Athanasios Valavanidis Corresponding Author Contact Information , E-ma... more ... The role of iron ions. Athanasios Valavanidis Corresponding Author Contact Information , E-mail The Corresponding Author , Anastasia Salika and Anna Theodoropoulou. ... References. Athanasiou, K., Viras, LG and Siskos, PA, 1986. ...
Synopsis Solar ultraviolet radiation (UVR) is implicated in many types of skin damage, such as ph... more Synopsis Solar ultraviolet radiation (UVR) is implicated in many types of skin damage, such as photodermatoses, photoageing, erythema, pigmentation, skin cancer etc. Free radicals and reactive oxygen species are considered to play an important role in cutaneous photocarcinogenesis. But skin is endowed with photoprotective agents, namely melanins and antioxidant enzymatic and non-enzymatic mechanisms. In this study we describe the in vivo electron spin resonance (ESR) signals of melanins after UVR exposure, using skin specimens of various types of mice, which were taken from different parts of their bodies. The ESR signals were used as a model for testing the antioxidant properties of butylated hydroxyanisole, tocopherol acetate, and octyl p-methoxycinnamate with butyl methoxy dibenzoyl methane and superoxide dismutase (SOD). Additional UVB radiation was applied to the skin samples in situ (in the cavity of the ESR spectrometer). Suppression of ESR signals of melanins was observed in...
Waste management & research : the journal of the International Solid Wastes and Public Cleansing Association, ISWA, 2008
Medical waste from hospitals and other healthcare institutions has become an imperative environme... more Medical waste from hospitals and other healthcare institutions has become an imperative environmental and public safety problem. Medical waste in Greece has become one of the most urgent environmental problems, because there are 14,000 tons produced annually, of which only a small proportion is incinerated. In the prefecture of Attica there is only one modern municipal medical waste incinerator (started 2004) burning selected infectious hospital waste (5-6 tons day(-1)). Fly and bottom residues (ashes) are collected and stored temporarily in barrels. High values of metal leachability prohibit the landfilling of these ashes, as imposed by EU directives. In the present study we determined quantitatively the heavy metals and other elements in the fly and bottom ashes of the medical waste incinerator, by inductively coupled plasma emission spectrometry (ICP) and by energy dispersive X-ray analysis (EDAX). Heavy metals, which are very toxic, such as Pb, Cd, Ni, Cr, Cu and Zn were found i...
This paper summarises results from 3 years of measurements in the building of the Chemistry Depar... more This paper summarises results from 3 years of measurements in the building of the Chemistry Department of the University of Athens, Greece, focusing mainly on the undergraduate and postgraduate laboratories. We measured levels of carbon dioxide (CO2), carbon monoxide (CO), sulphur dioxide (SO2), nitrogen dioxide (NO2), chlorine (Cl2), formaldehyde (HCHO), ozone (O3), total volatile organic compounds (TVOC), total respirable suspended
Several models attempt to explain the synergistic increase in lung cancer among workers exposed t... more Several models attempt to explain the synergistic increase in lung cancer among workers exposed to asbestos fibers, who were smokers at the same time. It is known that reactive oxygen species (ROS) are important mediators in asbestos-induced diseases, especially cancer. We studied quantitatively the formation of ROS (by spin trapping with DMPO) in aqueous buffer suspensions containing crocidolite (UICC), chrysotile (UICC and commercial, long fibers) alone, and in combination with aqueous cigarette tar extracts. It was observed that asbestos and cigarette tar act in a cooperative or synergistic way in the generation of hydroxyl radical spin adducts. Grinding of asbestos fibers and addition of EDTA (iron chelator) enhanced the intensity of the ESR signal. This enhancement progressed with time, probably due to the reaction of the extracted iron with the slow released hydrogen peroxide from tar extracts. It was observed a fivefold increase in the ESR signal (for crocidolite and aqueous tar extracts) in the formation of hydroxyl radicals via an iron-catalyzed Fenton reaction. These experimental results are suggest to be strong evidence to the fact that lung cancer has been found in asbestos workers exposed to high concentrations of fibers in the working environment who were smokers, and only rarely in nonsmokers.
Environmental pollution has changed dramatically in recent decades. This is an overview of recent... more Environmental pollution has changed dramatically in recent decades. This is an overview of recent advances in the use and significance of molecular biomarkers in environmental and human health risk assessment. Also, here we focused in aquatic organisms as diagnostic tools for aquatic pollution and ecological risk assessment in ecotoxicological studies. The use of molecular biomarkers in aquatic organisms is very important in order to address the broad spectrum of industrial, agricultural, commercial and domestic chemicals entering the environment and especially the aquatic environment and being taken up into the tissues of aquatic organisms. The biomarkers can act as prognostic tools for increased levels of pollution. Biomarkers can be defined as functional measures of exposure to chemical and physical pollutants at the sub-organismal, physiological and behavioural level. This encompasses molecular, cellular, genetic, immunological and physiological measures. The process of ecologic...
Pesticides are mostly synthetic chemicals that are used in agriculture to control pests. Pesticid... more Pesticides are mostly synthetic chemicals that are used in agriculture to control pests. Pesticides include herbicides, insecticides, fungicides, nematocides and rodenticides. The dramatic increase of global use of pesticides in the 1960 and 1970s was the result of growing population and the need for increased food production. Worldwide sales of pesticides increased from $2.7 billion in 1970 to $32,5 billion in 2001. Insecticides account for 1/3 of the world agrochemical market. Mechanization, monoculture, excessive use of fertilizers and pesticides lead to environmental pollution. Soil desertification, wildlife deaths, reduced biodiversity and excessive use of freshwater resources were some of the results. A number of pesticides were highly poisonous and many farmers developed chronic diseases, 30% of intentional suicides in developing countries were caused by toxic pesticides. In recent decades many persistent pesticides were banned or restricted, especially organochlorinated and ...
The complexes of 2-aminomethyl benzimidazole, 2-(beta-aminoethyl)benzimidazole, and 2-(alpha-amin... more The complexes of 2-aminomethyl benzimidazole, 2-(beta-aminoethyl)benzimidazole, and 2-(alpha-aminoethy-l)benzimidazole with Pt(II) and Pd(II) have been prepared. The molecular structure of the free ligands and their complexes were studied by IR and 1H NMR. It was concluded that the substituted benzimidazole derivatives behave as bidentate ligands, being bound to the metal atoms via the nitrogen of the -N = group and the amino group of the side chain of the benzimidazole ring. The metal complexes were tested for antineoplastic activity both in cultures of neoplastic cells (MEL-745, K-562, Colon 205, IMP-32, SK-N-SH) and in vivo in rodents bearing L-1210 leukemia. The antiproliferative activity of these agents was compared to that of cis-platin.
... The role of iron ions. Athanasios Valavanidis Corresponding Author Contact Information , E-ma... more ... The role of iron ions. Athanasios Valavanidis Corresponding Author Contact Information , E-mail The Corresponding Author , Anastasia Salika and Anna Theodoropoulou. ... References. Athanasiou, K., Viras, LG and Siskos, PA, 1986. ...
Synopsis Solar ultraviolet radiation (UVR) is implicated in many types of skin damage, such as ph... more Synopsis Solar ultraviolet radiation (UVR) is implicated in many types of skin damage, such as photodermatoses, photoageing, erythema, pigmentation, skin cancer etc. Free radicals and reactive oxygen species are considered to play an important role in cutaneous photocarcinogenesis. But skin is endowed with photoprotective agents, namely melanins and antioxidant enzymatic and non-enzymatic mechanisms. In this study we describe the in vivo electron spin resonance (ESR) signals of melanins after UVR exposure, using skin specimens of various types of mice, which were taken from different parts of their bodies. The ESR signals were used as a model for testing the antioxidant properties of butylated hydroxyanisole, tocopherol acetate, and octyl p-methoxycinnamate with butyl methoxy dibenzoyl methane and superoxide dismutase (SOD). Additional UVB radiation was applied to the skin samples in situ (in the cavity of the ESR spectrometer). Suppression of ESR signals of melanins was observed in...
Waste management & research : the journal of the International Solid Wastes and Public Cleansing Association, ISWA, 2008
Medical waste from hospitals and other healthcare institutions has become an imperative environme... more Medical waste from hospitals and other healthcare institutions has become an imperative environmental and public safety problem. Medical waste in Greece has become one of the most urgent environmental problems, because there are 14,000 tons produced annually, of which only a small proportion is incinerated. In the prefecture of Attica there is only one modern municipal medical waste incinerator (started 2004) burning selected infectious hospital waste (5-6 tons day(-1)). Fly and bottom residues (ashes) are collected and stored temporarily in barrels. High values of metal leachability prohibit the landfilling of these ashes, as imposed by EU directives. In the present study we determined quantitatively the heavy metals and other elements in the fly and bottom ashes of the medical waste incinerator, by inductively coupled plasma emission spectrometry (ICP) and by energy dispersive X-ray analysis (EDAX). Heavy metals, which are very toxic, such as Pb, Cd, Ni, Cr, Cu and Zn were found i...
This paper summarises results from 3 years of measurements in the building of the Chemistry Depar... more This paper summarises results from 3 years of measurements in the building of the Chemistry Department of the University of Athens, Greece, focusing mainly on the undergraduate and postgraduate laboratories. We measured levels of carbon dioxide (CO2), carbon monoxide (CO), sulphur dioxide (SO2), nitrogen dioxide (NO2), chlorine (Cl2), formaldehyde (HCHO), ozone (O3), total volatile organic compounds (TVOC), total respirable suspended
Several models attempt to explain the synergistic increase in lung cancer among workers exposed t... more Several models attempt to explain the synergistic increase in lung cancer among workers exposed to asbestos fibers, who were smokers at the same time. It is known that reactive oxygen species (ROS) are important mediators in asbestos-induced diseases, especially cancer. We studied quantitatively the formation of ROS (by spin trapping with DMPO) in aqueous buffer suspensions containing crocidolite (UICC), chrysotile (UICC and commercial, long fibers) alone, and in combination with aqueous cigarette tar extracts. It was observed that asbestos and cigarette tar act in a cooperative or synergistic way in the generation of hydroxyl radical spin adducts. Grinding of asbestos fibers and addition of EDTA (iron chelator) enhanced the intensity of the ESR signal. This enhancement progressed with time, probably due to the reaction of the extracted iron with the slow released hydrogen peroxide from tar extracts. It was observed a fivefold increase in the ESR signal (for crocidolite and aqueous tar extracts) in the formation of hydroxyl radicals via an iron-catalyzed Fenton reaction. These experimental results are suggest to be strong evidence to the fact that lung cancer has been found in asbestos workers exposed to high concentrations of fibers in the working environment who were smokers, and only rarely in nonsmokers.
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