Formation of fluorine technogenic anomalies in above-ground ecosystems of Siberia: Biological sorption,monitoring, possibility of lowering the negative impact

This paper studies how aluminum smelter emissions into the atmosphere affect the accumulation of fluorine by soil and plants, as well as change the chemical composition in leaves of woody plants. The ratio between total and extractable fluorine is ascertained to vary widely depending on the plant species. Meanwhile, gas resistant plants are characterized by an increased ash content in leaves (at the expense of K, P, Ca, etc.) and growth in the ratio between total and water-soluble fluorine. Plant resistance to fluorine that enters tissues depends on the capability of an organism to transform the toxicant into insoluble forms, which are not involved in physiological processes, i.e., on the presence of tissue elements with high precipitating capability. The gas-resistant species are ascertained to be characterized by high capability of limiting the intake of fluorine through roots, as well as its migration through a plant (especially to the organs that determine the further development of an organism).     

The Influence of Fluorine on the Disturbances of Homeostasis in the Central Nervous System

Fluorides occur naturally in the environment, the daily exposure of human organism to fluorine mainly depends on the intake of this element with drinking water and it is connected with the geographical region. In some countries, we can observe the endemic fluorosis—the damage of hard and soft tissues caused by the excessive intake of fluorine. Recent studies showed that fluorine is toxic to the central nervous system (CNS). There are several known mechanisms which lead to structural brain damage caused by the excessive intake of fluorine. This element is able to cross the blood-brain barrier, and it accumulates in neurons affecting cytological changes, cell activity and ion transport (e.g. chlorine transport). Additionally, fluorine changes the concentration of non-enzymatic advanced glycation end products (AGEs), the metabolism of neurotransmitters (influencing mainly glutamatergic neurotransmission) and the energy metabolism of neurons by the impaired glucose transporter—GLUT1. It can also change activity and lead to dysfunction of important proteins which are part of the respiratory chain. Fluorine also affects oxidative stress, glial activation and inflammation in the CNS which leads to neurodegeneration. All of those changes lead to abnormal cell differentiation and the activation of apoptosis through the changes in the expression of neural cell adhesion molecules (NCAM), glial fibrillary acidic protein (GFAP), brain-derived neurotrophic factor (BDNF) and MAP kinases. Excessive exposure to this element can cause harmful effects such as permanent damage of all brain structures, impaired learning ability, memory dysfunction and behavioural problems. This paper provides an overview of the fluoride neurotoxicity in juveniles and adults.     

Incorporation of fluorotryptophan into triostin antibiotics by Streptomyces triostinicus

The quinoxaline chromophores of the antibiotics produced by Streptomyces triostinicus are derived from tryptophan. Protoplasts of this organism made novel products when they were incubated with DL-5-fluorotryptophan or DL-6-fluorotryptophan. When added to batch cultures of the organism, DL-5-fluorotryptophan, at concentrations as low as 10 microM, inhibited both mycelial growth and triostin production, but gave rise to novel products. These have been characterized, using fast atom bombardment mass spectrometry, as novel triostins in which one or both of the quinoxaline rings contain an atom of fluorine. The chromatographic properties of the triostins arising from the incorporation of DL-5-fluorotryptophan are very similar to those of triostins containing chlorine or bromine at position 6 of the quinoxaline ring; they are clearly different from those having a chlorine atom at position 7. Accordingly, it is suggested that the carbon atom at position 5 of the indole ring of tryptophan ends up at position 6 of the quinoxaline ring system in triostins A and C.     

Antimutagenesis as organism defense system against damaging factors of endogenous and exogenous origin

Antimutagenic system is represented as the system combining all enzymatic and metabolic processes of the organism at all levels. The problem of supporting of autoantimutagenic system with antimutagenic preparations is discussed. A number of possible mechanisms of antimutagenic action of different substances are considered.     

Melatonin and neuroendocrine regulations in fish

Melatonin is the time-keeping molecule of the organism. The production by the pineal organ is responsible for the diurnal and annual rhythms of plasma melatonin content. This contributes to synchronizing behavioural, biochemical and physiological processes to the environmental variations in photoperiod and temperature. Conservation and diversity characterize the melatonin system in vertebrates: conservation because its nocturnal pattern of production as well as its synchronizing properties are a constant; diversity because the modalities of its biosynthesis and modes of action have been profoundly modified in the course of evolution. This review summarizes our current knowledge on the targets and modes of action of melatonin in fish and comparisons are made with mammals.     

Resistance to heavy metal toxicity in organisms under chronic exposure

The rate of changes of heavy metal ions concentrations in the organism or biological system will determine the choice of strategy of realization of heavy metal ions effect and, consequently, the biological effect itself. Which of the possible strategies will dominate, depend on the rate of changes of concentration of heavy metal ions in biological systems, functional activity of organism at the moment of metal action and on metals chemical properties. Keeping this view, the present review deals with the concept of time-based alterations of concentration of heavy metal ions (TACMI) in biological systems. On the basis of TACMI concept formation of organism resistance to metal ions action could be explained. In the event of slow increase of its concentration in organism, it produces induction of metallothioneins, other stress-proteins and relative changes in the whole metabolic system. This, first of all, results in formation of new specific epigenotypes, which provide higher resistance (hormesis effect) not only to metal ions that induced this effect, but also to such stress-factors as high temperature (at least, for micro-algae cells).     

Stereo-ultrastructure of the surface of HeLa cells following exposure to the MPEL of a number of trace elements

Scanning electron microscopy was used to study the surface ultrastructure of HeLa cells after the incubation with maximum-permissible concentrations (MPC) of zinc, nickel, cobalt, cadmium and fluorine for 2, 4 and 24 hours. It was established that the action of zinc, nickel, fluorine was accompanied by the ultrastructural changes in plasmalemma up to the end of experiment. The effect of the cobalt and cadmium MPC was short-term, and cells restored their typical surface morphology within 24 hours.     

土壤氟形态与氟污染土壤修复

我国土壤氟污染问题严峻,给部分地区人体健康和生态安全造成严重威胁,但土壤氟污染与防治问题仍没有受到人们的广泛关注.本文概述了土壤中氟的存在形态以及发生的主要化学反应,综述了近年来国内外有关氟污染土壤修复的研究进展,提出了今后氟污染土壤修复的研究方向,以期为氟污染土壤的修复提供借鉴和参考.土壤中氟主要分为5种形态,其中90%以上以残渣态存在,土壤溶液中的氟主要发生沉淀-溶解、络合-解离和吸附-解吸等反应来维持水-土系统中的氟平衡.目前,氟污染土壤修复技术研究主要集中在化学固定修复技术、化学淋洗技术、电动修复技术以及植物修复技术.今后需要重点研究氟在土壤中的赋存形态及其影响因子,筛选功能微生物和植物,开发联合修复技术以修复氟污染土壤.     

Accounting for Fluorine: Production,Use, and Loss

Fluorine is an essential element to human health and to the chemical industry. In spite of our dependence on fluorine and fluorine compounds, we have yet to learn to use them wisely. Our fluorine history, which spans about a hundred years, has had negative effects such as hydrofluoric acid pollution caused by aluminum smelters and ozone depletion due to chlorofluorocarbon (CFC) emissions. More recent concerns center on greenhouse effects from CFCs, hydrofluorocarbons (HFCs), and sulfur hexafluoride (SF6). In this article we note also that fluorine is a nonrenewable resource that is nonsubstitutable for many purposes. This article tracks fluorine from sources through conversion processes to end uses, most of which are dissipative. We present a stock‐flow model of the fluorine system. Based on this model we consider some possible measures that could be taken to increase the degree of recovery. To mention one example, a large percentage of the world demand for fluorspar could be supplied by the phosphate rock (fertilizer) industry, which currently dissipates a great deal of recoverable fluorine in waste phospho‐gypsum.     

Modification of radiosensitivity and the cyclic AMP system

The results of the experimental papers of the Soviet and foreign investigators concerning the role of cyclic AMP in modification of radiosensitivity of biological objects and the participation of cAMP system in the realization of radioprotective effect of various radioprotectants have been summarized. The action of radioprotectors on the cAMP level in cells and tissues of organism and their effect on the proteins activity of cAMP system has been considered. Particular attention has been given to the mechanisms of the radio-protective action of catecholamines on mammalian cells in vitro. On the grounds of the authors' own and literary data has been supposed that beta-adrenergic receptors and cAMP system, coupled with them, are obligatory for the performance of the radioprotective potency of catecholamines. The methodological problems of radiobiological experiments and adequate interpretation of results in compliance with terms of biochemistry and molecular endocrinology is discussed.     

Changes in the protein-synthesizing system of a HeLa cell culture exposed to a number of trace elements

The authors investigated the cytopathic action of maximal allowable concentrations (MAC) of zinc, nickel, cobalt, cadmium and fluorine on cell culture. The most significant changes in RNA synthesis were noticed after exposure to zinc MAC. After exposure to the MAC of zinc, nickel and fluorine considerable modifications of protein synthesis were recorded. It was established that the content of rRNA increased after incubation with all trace elements under study for 24 hours. The amount of protein experienced significant changes after nickel introduction into the incubation medium. It is concluded that exposure to some of trace elements entails considerable changes in cell metabolism.     

Mitotic cycle of a HeLa cell culture exposed to the maximum permissible concentrations of trace elements

It is shown that administration of certain trace elements in maximum allowable concentrations induces changes in metabolism and functionation of cells in the culture. Zinc, nickel, cobalt, cadmium and fluorine are stated to inhibit mitotic activity of HeLa cells by the end of 24 hours of their action. Parallel with this they promote a decrease in H3-thymidine incorporation into DNA. Besides these substances delay various stages of the mitotic cycle for cells.     

Plant adaptogens. III. Earlier and more recent aspects and concepts on their mode of action.

Stimulus-response coupling systems responsible for defence and adaptation of organism to stressors are multi-target and very complicated pharmacological systems, including the neuroendocrine (stress) and immune system. The mode of action of adaptogens is basically associated with the stress-system (neuroendocrine-immune complex) and can be directed on the various targets of the system involved in regulation (activation and inhibition) of stimulus-response coupling. However, clinical studies performed according to the most modern standards are quite limited. On the other hand there is an extensive amount of clinical experience and also established use in self care etc. These aspects are planned to be dealt within a subsequent article which will be devoted to the application in three areas: self care, adjuvants in medicine and curative action in some diseases. At this stage, nevertheless, it seems possible to define some most important "stress-markers" for evaluation of efficiency of adaptogens in experimental and clinical pharmacological studies. They can be both activating (catecholamines, LT-s, cytokines, NO, etc.--"switch on" system--which activates energetic and other resources of the organism), and deactivating (corticosteroids and PGE2-endogenous mediators of cellular communications, which protect cells and whole organism from overreacting to the activating messengers--"switch off" system) stress-messengers. The balance between the activities of the "switch on" and "switch off" systems reflects the well being of the organism. It could be established on different levels of the homeostasis (heterostasis) with different levels of the sensitivity to stressors (Figure 8). The response of stress system--"reactivity" is different at the various levels of heterostasis and depends on adaptation--capacity of the organism (or a cell) to protect itself. In the process of adaptation to stressor's effects the basal levels mediators of switch on (e.g. NO) and switch of (e.g. cortisol) systems are increasing but their balance (the ratio) does not change. In other words, adaptogens increase the capacity of stress system to respond to external signals at the higher level of the equilibrium of activating and deactivating mediators of stress response. Consequently, plant adaptogens can be defined as "smooth" pro-stressors which reduce reactivity of host defense systems and decrease damaging effects of various stressors due to increased basal level of mediators involved in the stress-response. In further studies of adaptogens it seems important to find correlation between adaptogenic activity (a decrease in the "reactivity" of the organism--the basal level of activating and deactivating messengers: ILs, LTB4, NO, PGE2, cortisol, but not their ratio) and their therapeutic efficiency (symptomatic evaluation).     

A Literary Review on Bovine Fluorosis

The toxic action of ingested fluorine compounds was first observed among people living in places where the fluorine content of the water was high. The clinical picture was dominated by the easily detectable lesions in the enamel of the teeth. Later injury to domestic animals also was found. Bovines have been reported to be more sensitive than man, and they are the most susceptible among the domestic animals, the susceptibility decreasing in the order: Cattle, sheep, rabbits, swine, rats and poultry (Phillips et al. 1955).     

Effect of ecdysterone on the metabolism of purine and pyrimidine nucleotides in chicken tissues]

Hormonal amounts (10(-7) M) of ecdysterone phytoecdysteroid have been studied for their effect on the metabolic processes in the chicken tissues. Changes in the blood serum parameters which characterize the state of the integral systems of mineral, lipid, protein and nucleotide metabolism as well as the dynamics of metabolism of nucleic acids and their precursors--purine and pyrimidine nucleotides in the tissues with actively functioning protein-synthesizing system prove that the biological effect of ecdysterone after its introduction to the bird organism manifests both in the non-genome early phase of the action (0-1 h) and in the late genome phase (24-72 h), i.e. in analogy to the time of response to the introduction of classical steroid hormones. It is supposed that polyfunctional early effect of ecdysterone is mediated by its action on one of universal transmembrane signal systems of the cells--adenylate cyclase or polyphosphoinosite one, while the presence of the expressed changes in metabolism of nucleic acids in the late phase unambiguously indicate to its action in the bird organism as that of a typical steroid hormone.     

Activity of fluoro and deoxy analogues of glycerol as substrates and inhibitors of glycerol kinase

Analogues of glycerol in which each of the three hydroxy groups is successively replaced by fluorine or hydrogen have been examined as substrates or inhibitors of glycerol kinase (Candida mycoderma) to assess the ability of fluorine to mimic a substrate hydroxy group in enzyme-analogue interactions. The four diols resulting from replacement of the hydroxy groups at C-1 or C-2 of sn-glycerol by fluorine or hydrogen are weak substrates. Similar substitution of the C-3 hydroxy group gives compounds which act as competitive inhibitors of glycerol or dihydroxyacetone phosphorylation but show no activity as substrates. Comparison of the steady-state kinetic parameters of the corresponding analogues shows that replacement of a hydroxy group by either fluorine or hydrogen leads to compounds with similar activity in this system. A convenient synthesis of (+)-propane-1,2-diol is described.     

Biology of size and gravity]

Gravity is a force that acts on mass. Biological effects of gravity and their magnitude depend on scale of mass and difference in density. One significant contribution of space biology is confirmation of direct action of gravity even at the cellular level. Since cell is the elementary unit of life, existence of primary effects of gravity on cells leads to establish the firm basis of gravitational biology. However, gravity is not limited to produce its biological effects on molecules and their reaction networks that compose living cells. Biological system has hierarchical structure with layers of organism, group, and ecological system, which emerge from the system one layer down. Influence of gravity is higher at larger mass. In addition to this, actions of gravity in each layer are caused by process and mechanism that is subjected and different in each layer of the hierarchy. Because of this feature, summing up gravitational action on cells does not explain gravity for biological system at upper layers. Gravity at ecological system or organismal level can not reduced to cellular mechanism. Size of cells and organisms is one of fundamental characters of them and a determinant in their design of form and function. Size closely relates to other physical quantities, such as mass, volume, and surface area. Gravity produces weight of mass. Organisms are required to equip components to support weight and to resist against force that arise at movement of body or a part of it. Volume and surface area associate with mass and heat transport process at body. Gravity dominates those processes by inducing natural convection around organisms. This review covers various elements and process, with which gravity make influence on living systems, chosen on the basis of biology of size. Cells and biochemical networks are under the control of organism to integrate a consolidated form. How cells adjust metabolic rate to meet to the size of the composed organism, whether is gravity responsible for this feature, are subject we discuss in this article. Three major topics in gravitational and space biology are; how living systems have been adapted to terrestrial gravity and evolved, how living systems respond to exotic gravitational environment, and whether living systems could respond and adapt to microgravity. Biology of size can contribute to find a way to answer these question, and answer why gravity is important in biology, at explaining why gravity has been a dominant factor through the evolutional history on the earth.     

Gaseous messengers in the nervous system

Nitric oxide is the first gaseous messenger whose functions were comprehensively studied in different systems of organism. Recently, new data on the physiological role of other endogenous gases: carbon monoxide and hydrogen sulfide, appeared. The role of gases in gastrointestinal tract and cardiovascular system have been established; however, data on their function and mechanisms of action in nervous system are insufficient. This article highlights the current information on the role of gaseous messengers in central and peripheral nervous system.     

Deciphering the mechanisms of homeostatic plasticity in the hypothalamo-neurohypophyseal system--genomic and gene transfer strategies

The hypothalamo-neurohypophyseal system (HNS) is the specialised brain neurosecretory apparatus responsible for the production of a peptide hormone, vasopressin, that maintains water balance by promoting water conservation at the level of the kidney. Dehydration evokes a massive increase in the regulated release of hormone from the HNS, and this is accompanied by a plethora of changes in morphology, electrical properties and biosynthetic and secretory activity, all of which are thought to facilitate hormone production and delivery, and hence the survival of the organism. We have adopted a functional genomic strategy to understand the activity dependent plasticity of the HNS in terms of the co-ordinated action of cellular and genetic networks. Firstly, using microarray gene-profiling technologies, we are elucidating which genes are expressed in the HNS, and how the pattern of expression changes following physiological challenge. The next step is to use transgenic rats to probe the functions of these genes in the context of the physiological integrity of the whole organism.     

A rationale for the therapeutic action of aprotinin.

Aprotinin, a protease inhibitor, has been used in a wide variety of pathophysiological states thought to be associated with an increase in protease activity. Opinion differ with respect to the success of the therapy. This paper proposes a rationale for the therapeutic action of aprotinin based on biochemical and physiological evidence. In the kallikrein-kinin system, in addition to kallikrein, other serine-esterases such as trypsin, plasmin, etc. can generate kinin production. In certain disease states such as pancreatitis there is not only an increase in serine-protease activity but frequently these enzymes reach parts of the organism where they are not found in health. Thus in such circumstances increased production of kinins can result. The consequences of increased kinin generation are discussed in light of work indicating their role in metabolic and circulatory homeostasis. Aprotinin is specifically a serine-esterase inhibitor. It is suggested that perhaps the most important action of this compound is as an inhibitor of the kallikrein-kinin system. On this basis a therapeutic regime in various disease states for the use of aprotinin, which allows for control of kinin generation, is suggested.