[Biological function of some elements and their compounds. III. Zinc--component and activator of enzymes]. / Funkcje biologiczne wybranych pierwiastków. III. Cynk--skladnik i aktywator enzymów.

Zinc plays many basic metabolic functions in human organism as a co-enzymatic or activator about 80 enzymes. It participates in metabolic changes of lipids, proteins and carbohydrates. Zinc easily binds with nucleic acids with beneficial effect on active transport, protein biosynthesis, transcription, and mRNA synthesis. It is inevitable for proper functioning of the respiratory and reproductive systems. Zinc acts protectively in lead and cadmium poisoning and it participates in the elimination of free superoxide radicals (it inhibits of oxygenation of non-saturated fatty acids). It enables normal functioning of the skin and mucous membranes. Zinc deficit can lead to many ailments and disorders of the following systems: muscular, nervous digestive, reproductive, hormonal, immune.

[Biological function of some elements and their compounds. IV. Silicon, silicon acids, silicones]. / Funkcje biologiczne pierwiastków i ich zwiazków. IV. Krzem, kwasy krzemowe, silikony.

The review is devoted for the occurance, meaning of silicon and their compounds, especially silicon acids and silicones. Silicon participates in biosynthesis of collagen, the basic component of connective tissue. It strengthens and makes the walls of blood vessels more flexible, diminishes capillaries permeability, accelerates healing processes, has a sebostatic activity, strengthens hair and nails. This element has a beneficial effect on phosphorylation of proteins saccharides, and nucleotides. It is also essential for the formation of cytoskeleton and other cellular structures of mechanical or supportive function. Silicon is an initial substrate for obtaining silicones. These are synthetic polymers, in which silicon atoms are bound by oxygen bridges. They are used in almost all kinds of products due to their most convenient physical and chemical properties: moistening and film-forming, giving liquid form increasing solubility. Silicon acids form colloid gel, silica gel, with absorptive abilities, like active carbon.

[Reactive nitrogen and oxygen species]. / Reaktywne formy azotu i tlenu.

Reactive nitrogen species (RNS) and reactive oxygen species (ROS) are mainly free radicals which including non-paired electrons. They are constantly formed as side products of biological reactions. They are also generated directly and indirectly by the cells which were exposed to environmental stress, i.e., UV radiation, ionizing radiation, xenobioticts, light-absorbing compounds, e.g., porphyrines. These factors, which are a source of free radicals, initiate a significant signaling cascade inducing many changes in cells, such as cancerogenic transformation or cell death. Cells protect themselves against oxidative stress by means of antioxidative enzymes and compounds which in their structure have redox sensitive spots.

[Biological function of some elements and their compounds. I. Oxygen--the element of life and death]. / Funkcje biologiczne wybranych pierwiastków i ich zwiqzków. I. Tlen--pierwiastek zycia i smierci.

Oxygen in cells occurs with carbon and hydrogen in most organic compounds that have either structural or metabolic functions. Atomic and molecular oxygen in singlet form or as free radicals (i.e., superoxide anionic radical, hydroxide radical) and as hydrogen peroxide, peroxidenitrate (III), nitrogen oxide are harmful to cellular structure and its metabolism and induce harmful genic mutations. Oxygen reactive species are secondary signaling molecules for transcription factors and cytokines. Therefore, it is crucial to maintain homeostasis at the level of reaction of oxidation and reduction. It is important for such significant biological processes as DNA synthesis, enzymes activation, cellular cycle regulation, gene transcription activation, and apoptosis. The review is also devoted for oxygen carriers in living organisms, e.g., hemoglobin, mioglobin and the toxicity of oxygen and ozone.

[Biological function of some elements and their compounds. II. Selenium, selenate, selenium organic compounds]. / Funkcje bioliogiczne pierwiastków i ich zwiazków. II. Selen, seleniany, zwiazki selenoorganiczne.

The review is devoted to the role of selenium and its compounds for living organisms. Selenium as an antioxidant protects the cells from generating free radicals. It constitutes an integral part of approximately 20 enzymes. Glutathione peroxidase, which participates in metabolism of H2O2 and plays a protective role against lipids oxidation is one of the most important enzymes containing of selenium. In organisms, selenium occurs most frequently in amino acids, where it replaces sulphur, such as selenocystein and selenometionine, as well as in bonds with proteins. Amino acid bonds are significant in functions of RNA, in biosynthesis and activity of thyroid hormones. Selenium deficiency leads to decrease in selenium-dependent glutathione peroxidase, which occurs in mitochondria and cytosole. It causes also heart muscles diseases, the skeletal and circulatory systems disorders, neoplasms, infections, and cold.

Applications of the extractive methods in chemical analysis of some psychotropic drugs.

The review is devoted for the solid phase extraction and the extractive spectrophotometric methods for the determination of some psychotropic drugs, e.g. phenothiazines, thioxanthenes, dibenzothiazines, fluoxetine, fluvoxamine, trazodone.

Analytical Applications of Reactions of Iron(III) and Hexacyanoferrate(III) with 2,10-Disubstituted Phenothiazines.

The presented review is devoted to analytical applications of reactions of Fe(III) and K(3)[Fe(CN)(6)] with 2,10-disubstituted phenothiazines (PT). It was found that iron(III) and hexacyanoferrate(III) ions in acidic media easily oxidized PT with the formation of colored oxidation products. This property has been exploited for spectrophotometric determination of iron(III) ions and phenothiazines. Some flow-injection procedures of the determination of PT based on the oxidation reaction by means of the above-mentioned oxidants have been proposed. In the presented review, the application of 2,10-disubstituted phenothiazines as indicators in complexometric titration of iron(III) as well as procedures of PT determination based on generation of ternary compound in the system Fe(III)-SCN(-)- PT was also described.

[Influence of reactive nitrogen and oxygen species on human organism]. / Wplyw reaktywnych form azotu i tienu na organizm czlowieka.

Reactive nitrogen species (RNS) and oxygen (ROS) species play a very positive and important role in the process of cells communication. The maintenance of certain level of radicals in cells is necessary for the information flow between cells and inside cells. The liquidation of free radicals presence or an increase in their level may to some extent disturb the cellular communication. Even slight fluctuations in the basic level of ROS significantly affect the change in the cell's metabolism, expression of genes and posttranslational modification of proteins. When the level of free oxygen radicals exceeds the antioxidative possibilities of the cell, an oxidative stress occurs, which causes many diseases and accelerated aging of the organism. Aging is natural, complex process, but apart from the programmed aging the reactive oxygen molecules, which are external agressors, accelerate this process.

[Organism defense against reactive oxygen species]. / Obrona organizmu przed reaktywnymi formami tlenu.

Reactive oxygen species (ROS) are constantly formed as side products of biological reactions in which electron transfer goes on. ROS include superoxide anion radical O2*, hydroxide radical *OH, hydrogensuperoxide radical HO2*, hydrogen peroxide and singlet oxygen. The maintenance of homeostasis at the redox level is particularly important for many biological processes such as: DNA synthesis, enzymes activation and regulation genes, regulation of cellular cycle and programmed death of the cell. Cells protect themselves against oxidative stress by means of antioxidants enzymes and compounds which in their structure have redox sensitive spots.

[Reactive oxygen species and aging of organism]. / Reaktywne formy tlenu a starzenie sie organizmu.

The review is devoted for reactive oxygen species (ROS). Numerous processes of cellular oxidation proceed through the stage of free radicals. These radicals containing odd electrons are formed in the course of many biochemical reactions. As a result of aging, as well as action of various environmental factors, eg. ionizing radiation or different chemical compounds synthesis of free radicals increases, whereas the detoxication ability decreases. Free radicals: O(2-)*, *OH, ROO*, RO* and O3, H2O2, singlet oxygen may be removed by means of defence systems of living organism and antioxidants.

Spectrophotometric determination of olanzapine by its oxidation with N-bromosuccinimide and cerium(IV)sulfate.

Three simple spectrophotometric methods have been described for the assay of olanzapine in its pure and pharmaceutical formulations. The direct method (A) is based on the drug oxidation with excess of N-bromosuccinimide in acidic medium and the two indirect methods (B and C) are based on the oxidation of the drug with excess of N-bromosuccinimide and cerium(IV)sulfate, followed by the reaction of the unconsumed oxidants with celestine blue. The calibration graphs were linear over the range 10 - 120 microg mL(-1) (method A), 0.5 - 6.0 microg mL(-1) (method B) and 0.6 - 3.0 microg mL(-1) (method C). After validation, the proposed methods were successfully applied to assay of olanzapine in its commercial tablets with mean percentage recoveries of 101.23 +/- 0.10, 96 +/- 0.10 and 94 +/- 0.04%. The mechanism of olanzapine oxidation with N-bromosuccinimide was also proposed.

Efficient oxidizing agents for determination of 2,10-disubstituted phenothiazines.

2,10-Disubstituted phenothiazines are the best drugs in psychiatry. Several methods for their analysis have been reported in the literature. The official methods are based on non-aqueous titration or spectrophotometry. Various oxidizing agents have been used for the spectrophotometric determination of 2,10-disubstituted phenothiazines, e.g. Ce(SO4)2, NH4VO3, K2S208, KIO4, KIO3, KBrO3, FeCl3, NaNO2, H2O2, chloramine T, p-benzoquinone, N-bromosuccinimide. Oxidation reactions of phenothiazines were also used for their determination by flow-injection methods.

Analytical studies and application of reaction of promazine and thioridazine hydrochlorides with some oxidants.

The run and analytical application of oxidation reaction of promazine (PM) and thioridazine (TR) hydrochlorides with iron(III) and ferrocyanide(III) are described. The coloured products of oxidation absorb at 512 nm for promazine and 634 nm for thioridazine. This property is a basis of a rapid, accurate and sensitive spectrophotometric method for determination of these phenothiazines. The elaborated methods allow to determine 3-28 microgPM/ml in Fe(III)-PM and 2-11 microgPM/ml in [Fe(CN)6](3-)-PM systems, 2.5-22 microgTR/ml in the Fe(III)-TR and 4-16 microgTR/ml in [Fe(CN)6](3-)-TR systems.

Extractive-spectrophotometric determination of some phenothiazines with dipicrylamine and picric acid.

Dipicrylamine and picric acid have been tested as reagents for the determination of promethazine and perphenazine. They react in neutral media with these drugs forming the coloured compounds. The compounds are sparingly soluble in water and quantitatively extracted into organic solvents. The extracts are intensely coloured and very stable. These properties have been exploited for the extractive spectrophotometric determination of promethazine and perphenazine in pure solutions and pharmaceuticals. Linear calibration graphs were obtained in the concentration range 4-40, 3-30 microg ml(-1) of promethazine and 4-80, 8-60 microg ml(-1) of perphenazine for picric acid and dipicrylamine, respectively. The relative standard deviation (RSD) is less than 0.8%.