Tellurium: A Rare Element with Influence on Prokaryotic and Eukaryotic Biological Systems.

Metalloid tellurium is characterized as a chemical element belonging to the chalcogen group without known biological function. However, its compounds, especially the oxyanions, exert numerous negative effects on both prokaryotic and eukaryotic organisms. Recent evidence suggests that increasing environmental pollution with tellurium has a causal link to autoimmune, neurodegenerative and oncological diseases. In this review, we provide an overview about the current knowledge on the mechanisms of tellurium compounds' toxicity in bacteria and humans and we summarise the various ways organisms cope and detoxify these compounds. Over the last decades, several gene clusters conferring resistance to tellurium compounds have been identified in a variety of bacterial species and strains. These genetic determinants exhibit great genetic and functional diversity. Besides the existence of specific resistance mechanisms, tellurium and its toxic compounds interact with molecular systems, mediating general detoxification and mitigation of oxidative stress. We also discuss the similarity of tellurium and selenium biochemistry and the impact of their compounds on humans.

Probabilistic analysis of a concrete column in an aggressive soil environment.

Sulphate attack is one of the most important factors that limit the lifetime of pure concrete constructions. Harsh environmental conditions have a large impact on the operational costs of concrete columns or piles dipped into soil. The results are non-deterministic; therefore, reliability analysis is often used. The strength characteristics of the substrate around the construction were modelled as one-dimensional prismatic beams related with random p-y curves. Sulphate deterioration is defined as a set of random variables jointed with two dimensional mechanical systems at acceptable levels. Fick's second law describes the penetration of sulphate ingress into pure concrete with explicit numerical solutions for boundary conditions and an increase in the transition factor under the progress of sulphate ingress. This process was partially solved via analytical methods for sulphate ion transport and numerically for a random field. This solves the mechanical task and determines the system reliability. A numerical example is provided to illustrate the proposed method to prevent unexpected structural failures during column service life. The proposed methodology can assist designers and can help to make decisions on existing foundations to ensure the safety of geotechnical construction.

Hypersensitivity to metallic implants: pathophysiologic and diagnostic considerations.

Metals are ubiquitous in the surrounding environment and constitute an important class of substances that can act as allergens. Consumer products such as earings, zip, jewellery, cosmetics, paints, dental and body implants as well as endovascular, intracardiac and orthopedic devices are made from metals. Metal anions eluted from various metals  are common allergic sensitizers. In Europe nickel, chromium and cobalt induce allergic skin reactions in about 20%, 4%, and 7% while in the United States14%, 4%, and 9% respectively.

Controlled trial of safety and efficacy of bright light therapy vs. negative air ions in patients with bipolar depression.

Treatment of bipolar disorder often results in patients taking several drugs in an attempt to alleviate residual depressive symptoms, which can lead to an accumulation of side effects. New treatments for bipolar depression that do not increase the side effect burden are needed. One nonpharmacological treatment with few side effects, bright light therapy, has been shown to be an effective therapy for seasonal affective disorder, yet has not been extensively studied for other forms of depression. Forty-four adults with bipolar disorder, depressed phase were randomized to treatment with bright light therapy, low-density or high-density negative ion generator for 8 weeks. The primary measure of efficacy was the Structured Interview Guide for the Hamilton Depression Rating Scale with Atypical Depression Supplement (SIGH-ADS). Adverse events were assessed using the Young Mania Rating Scale (YMRS) and Systematic Assessment for Treatment Emergent effects (SAFTEE). All outcome variables were statistically analyzed using a mixed model repeated measure analysis of variance (ANOVA). The results showed no statistically significant differences between groups in any outcome measures at study end point; adverse events, including switches into hypomania, were rare. Further research is needed to determine the efficacy of bright light therapy in this population.

[Ecological and hygienic evaluation of microbiological process in the soil contaminated by anion surfactants and heavy metals]. / Ekologo-gigienicheskaia otsenka mikrobiologicheskikh protsessov v pochve pri zagriaznenii anionnymi poverkhnostno-aktivnymi veshchestvami i tiazhelymi metallami.

Disorders in microbiocenosis and biological activity of different types of soil were studied in a laboratory model experiment and the survival of reference and pathogenic microorganisms exposed to sulfonol and lead was evaluated. The most sensitive tests for such studies are evaluation of the number of nitrifiable bacteria, nitrifying, proteolytical, dehydrogenase, and cellulase activities, and survival of Salmonella and lactose-positive Escherichia coli in soil.

Flame atomic absorption spectrometric determination of trace chromium in various standard samples after preconcentration with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol.

Chromium can be quantitatively retained as 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-tetra-phenylborate(TPB) complex onto microcrystalline naphthalene in the pH range 4.8-5.9 from a large volume of aqueous solutions of various standard samples. After filtration, the solid mass consisting of the chromium complex and naphthalene was dissolved with 5 mL of dimethylformamide and the metal was determined by air-acetylene FAAS. A detection limit of 4 ng/mL for chromium was established. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the trace determination of chromium in various standard alloys and biological samples.

An investigation of the effects of negative air ions on responses to submaximal exercise at different times of day.

The influence of negative air ions on rectal temperature (Tr), heart rate (HR), oxygen uptake (VO2) and ventilation (VE) was examined in male subjects (n = 8) at rest and during two successive exercise bouts of 90 W and 180 W, each for 20 min on a cycle ergometer. Exposures at 4 different times of day (01:30, 10:00, 14:00 and 18:00 h) were presented to subjects under experimental and control conditions using a cross-over design. Results indicated that negative air ions significantly reduced resting values of all physiological variables (p between 0.05 and 0.01): these effects tended to disappear under exercise conditions, except for Tr. There was no significant effect of air ions on state anxiety pre- or post-exercise or on the perception of effort (p > 0.05). The significant circadian rhythm in Tr was reduced in amplitude by air ionisation although it retained its normal phase. Results confirm that negative air ions are biologically active and that they do affect the body's circadian rhythmicity.

Cations and anions in drinking water as putative contributory factors to endemic goitre in Plateau State, Nigeria.

The prevalence of endemic goitre in Plateau State, Nigeria was established and an attempt was made to identify some of the possible environmental goitrogenic agents in the region to establish their likely relationship with the goitre endemicity. Iodine deficiency appears to be a major aetiological factor for the disease as indicated by low iodine levels observed in portable drinking water and in daily urinary excretion. The carbonate (CO3-) content of drinking water supply was found to bear a significant positive correlation with the goitre rate for the entire state (p less than 0.005). The calcium (Ca++) and magnesium (Mg++) levels of the drinking water also exhibited relatively good linear direct correlations with the percentage goitre distribution in a region, nearly 2/3 of the state. It is concluded that there is possibly an interplay of several factors and in particular the carbonate content of drinking water which, in association with a state of iodine deficiency, may be regarded as responsible for the goitre endemic seen in this part of the Continental Africa.

The serotonin irritation syndrome--a new clinical entity?

The literature on the possible existence of a "serotonin irritation syndrome" is examined. This syndrome is an anxiety state occurring in the presence of elevated levels of atmospheric or ambient cations and is associated with elevated central and peripheral serotonin levels. Investigation of these cations' effects on microbes, insects, and mammals, including humans, shows a disruption of normal activity. It is suggested that clinicians become acquainted with the potential relationship between cation exposure and serotonin in their treatment of anxious patients. Further research exploring the etiology and diagnostic definition of this entity is urged.

The effect of positive and negative air ions on bronchial asthma.

The effect of prolonged exposure to either positive or negative small air ions was studied in nine patients with bronchial asthma, of whom seven had reported increased respiratory symptoms in association with weather changes. On consecutive days, while grounded, patients were exposed for six hours to approximately 10,000/cc of either positive or negative ions. Pulmonary function, pulse and blood pressure were measured throughout the exposure. Questionnaires to assess emotional state and physical symptoms were completed after 15 minutes and five hours each day. Urinary 5-hydroxy indoleacetic acid (5HIAA) excretion was measured. Patients were continued on theophylline but adrenergics and corticosteroids were withheld. No patient experienced an exacerbation of asthma. Symptoms, pulmonary function, pulse and blood pressure, urinary 5HIAA excretion and the response to the questionnaires did not differ significantly between the two ion exposures. Thus moderately long exposure to positive or negative small air ions did not influence the clinical condition of these patients, many of whom reported exacerbations with weather changes. The findings do not support a significant role of small air ions in exacerbations or treatment of bronchial asthma.