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The purpose of our study was to quantitatively and qualitatively evaluate changes in the microbiome of the opisthosoma of the spider Steatoda grossa (Theridiidae) in response to short-term (4 weeks) and long-term (12 months) exposure to copper, as a biogenic element, and cadmium, as a xenobiotic, administered under controlled laboratory conditions using Drosophila hydei flies as prey. Regardless of the duration of exposure to metals-contaminated food, their concentrations in the bodies of the tested individuals significantly exceeded control values. The highest concentration of the metals was recorded in individuals after long-term exposure (with levels exceeding those of the control by 30 times for Cd and 5 times for Cu). The presence of metals in the food had a significant effect on the qualitative and quantitative structure of the microbiome, particularly in individuals exposed to contaminated food for the short term. Spiders fed cadmium-supplemented prey exhibited a microbiome dominated by Bacillales, Enterobacteriales, Entomoplasmatales, and Burkholderiales. In contrast, Bacillales, Mycobacteriales, Bacteroidales, and Micrococcales were dominant in individuals fed copper-supplemented food for 1 month. Differences in microbiome structure between metal-treated and control individuals disappeared after 1 year of culture. Spiders cultured for 1 year, whether fed with or without metal-treated food, exhibited a microbiome rich in species diversity, with an equal distribution of individual bacterial taxa. It is possible that the microbiome itself actively participated in alleviating problems associated with food metal contamination.

This paper proposes a system, the Smart Learning Design Framework, designed to support the development of pedagogically sound learning material within an integrated, platform-independent data structure. The system supports sharing, reuse and adaptation of learning material via a metadata-driven philosophy that enables the technicalities of the system to be imperceptible to the author and consumer. The system proposes the use of pedagogically focused metadata to support and guide the author and to adapt and deliver the content to the targeted consumer. A prototype of the proposed system, which provides proof of concept for the novel processes involved, has been developed. The paper describes the Smart Learning Design Framework and places it within the context of alternative learning object models and frameworks to highlight similarities, differences and advantages of the proposed system.

Background and Purpose: Adamantanes were listed as an interesting option as an early intervention against COVID-19. We aimed to evaluate the effectiveness of amantadine in preventing the progression of COVID-19 and its neurological sequelae., Methods: Unvaccinated patients with confirmed SARS-CoV-2 infection within 5 days were enrolled. Subjects were randomized (50:50) to amantadine (AMD; 100 mg twice daily) or placebo (PLB) for 14 days. The Ordinal Scale for Clinical Improvement of the World Health Organization (OSCI-WHO) was the primary measure. Secondary endpoints included assessment for fatigue; depression, disorders of smell and taste, and sleepiness on Days 1 and 15., Results: We enrolled 99 patients (49 AMD and 50 PLB). Disease progression (OSCI-WHO = 4) was observed in 6% (AMD) and 8% (PLB) patients (p > 0.05) with further deterioration (OSCI-WHO〉4) in 0% (AMD) and 8% (PLB) patients (p > 0.05). Complete recovery on Day 15 was 60% higher in the AMD compared with the PLB group (p = 0.025). There was improvement in taste (AMD: p = 0.003; PLB: p = 0.0001) and smell (AMD: p = 0.005; PLB: p = 0.0004) but not in fatigue in both groups. Improvement was observed in the AMD (p = 0.010) but not in the PLB group (p = 0.058) when assessing depression as well as sleepiness (AMD: p = 0.0002; PLB: p = 0.341). There was one death in the PLB group (2.0%) and none in the AMD group (p > 0.05) until Day 210. Overall, the drug was well tolerated., Conclusion: The central effects of amantadine on the nervous system with reduction of sleepiness and depression might have had a supportive effect on faster recovery in early COVID-19 patients., (© 2023 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.)

Background: COVID-19, a disease caused by infection with the SARS-CoV-2 virus, is asymptomatic or mildly symptomatic in most cases. Some patients, usually burdened with risk factors develop acute respiratory failure and other organ dysfunction. In such cases, the mortality rate is very high despite the use of intensive therapy. Amantadine has complex activity including antiviral, antiinflammatory and dopaminergic effects. This clinical trial will assess the efficacy and safety of amantadine in the prevention of COVID-19 progression toward acute respiratory failure and neurological complications., Methods and Results: The trial will enroll 200 patients who are positive for SARS-CoV-2 infection and have one or more risk factors for worsening the disease. These patients will be included as hospitalized or ambulatory subjects for early treatment of illness. The recruitment will take place in 8 centers covering different regions of Poland. For 14 days they will be given either 200 mg of amantadine a day or placebo. Our hypothesis is a considerable reduction in the number of patients with progression toward respiratory insufficiency or neurological complications thanks to the treatment of amantadine., Conclusions: Demonstrating the efficacy and safety of amantadine treatment in improving the clinical condition of patients diagnosed with COVID-19 is of great importance in combating the effects of the pandemic. It has potential to influence on the severity and course of neurological complications, which are very common and persist long after the infection as long-COVID syndrome., Clinical Trial Registration: www., Clinicaltrials: gov identification no. NCT04854759; Eudra CT number: 2021-001144-98 (dated 27 February 2021)., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The garden nasturtium (Tropaeolum majus L.) belongs to the family Tropaeolaceae. Native to South America it was brought to Europe in XVI century. It is a plant with numerous healing properties. Medicinal plants such as the garden nasturtium contain trace elements and bioactive compounds which can be easily absorbed by the human body. The flowers and other parts of the garden nasturtium are a good source of micro elements such as potassium, phosphorus, calcium and magnesium, and macro elements, especially of zinc, copper and iron. The essential oil, the extract from the flowers and leaves, and the compounds isolated from these elements have antimicrobial, antifungal, hypotensive, expectorant and anticancer effects. Antioxidant activity of extracts from garden nasturtium is an effect of its high content of compounds such as anthocyanins, polyphenols and vitamin C. Due to its rich phytochemical content and unique elemental composition, the garden nasturtium may be used in the treatment of many diseases for example the illnesses of the respiratory and digestive systems. High content of erucic acid in nasturtium seeds makes it possible to use its oil as treatment in adrenoleukodystrophy. It is also applied in dermatology because it improves the condition of skin and hair. More recently, the flowers of this species have been used as a decorative and edible element of some types of dishes. Aim of the review was to summarize available data concerning garden nasturtium Tropaeolum majus L.

Collagen, the most abundant protein in mammals, is able to form fibrils, which have central role in tissue repair, fibrosis, and tumor invasion. As a component of skin, tendons, and cartilages, this protein contacts with any implanted materials. An inherent problem associated with implanted prostheses is their propensity to be coated with host proteins shortly after implantation. Also, silicone implants undergoing relatively long periods of contact with blood can lead to formation of thrombi and emboli. In this paper, we demonstrate the existence of interactions between siloxanes and collagen. Low-molecular-weight cyclic siloxane (hexamethylcyclotrisiloxane-D3) and polydimethylsiloxanes (PDMS) forming linear chains, ranging in viscosity from 20 to 12,000 cSt, were analyzed. We show that D3 as well as short-chain PDMS interact with collagen, resulting in a decrease in fibrillogenesis. However, loss of collagen native structure does not occur because of these interactions. Rather, collagen seems to be sequestered in its native form in an interlayer formed by collagen-siloxane complexes. On the other hand, silicone molecules with longer chains (i.e., PDMS with viscosity of 1000 and 12,000 cSt, the highest viscosity analyzed here) demonstrate little interaction with this protein and do not seem to affect collagen activity., (© 2015 The Authors. Journal of Pharmaceutical Sciences published by Wiley Periodicals, Inc. and the American Pharmacists Association.)

Cationic amino acid-based surfactants were synthesized via solid phase peptide synthesis and terminal acylation of their α and ε positions with saturated fatty acids. Five new lipopeptides, N-α-acyl-N-ε-acyl lysine analogues, were obtained. Minimum inhibitory concentration and minimum bactericidal (fungicidal) concentration were determined on reference strains of bacteria and fungi to evaluate the antimicrobial activity of the lipopeptides. Toxicity to eukaryotic cells was examined via determination of the haemolytic activities. The surface-active properties of these compounds were evaluated by measuring the surface tension and formation of micelles as a function of concentration in aqueous solution. The cationic surfactants demonstrated diverse antibacterial activities dependent on the length of the fatty acid chain. Gram-negative bacteria and fungi showed a higher resistance than Gram-positive bacterial strains. It was found that the haemolytic activities were also chain length-dependent values. The surface-active properties showed a linear correlation between the alkyl chain length and the critical micelle concentration.

Background: Biofilms play an important role in the pathogenesis of several chronic infections and nosocomial infections related to indwelling medical devices., Methods: To assess the efficacy of IB-367 and linezolid (LZD) in the treatment of central venous catheter (CVC) infections using the antibiotic-lock technique, in vitro and in vivo studies were performed. The in vitro antibiotic susceptibility assay for Staphylococcus aureus and Enterococcus faecalis biofilms developed on 96-well polystyrene tissue culture plates was performed to determine the activity of the compounds. Efficacy studies were performed in rat models of Gram-positive CVC infection. Silastic catheters were implanted into the superior cava of adult male Wistar rats. Twenty-four hours after implantation, the catheters were pretreated by filling with IB-367. Thirty minutes later, rats were challenged via the CVC with 1.0 x 10(6) CFU (colony forming units) of S aureus strain diffuse Smith and clinical isolate of slime-producing E faecalis. Administration of LZD into the CVC at a concentration equal to the minimum bacteriocidal concentration observed using adherent cells or at a much higher concentration (1024 microg/mL) began 24 hours later., Results: Both for S aureus and E faecalis, the killing activities of LZD against adherent bacteria were at least 4-fold to 8-fold lower than that against freely growing cells. For both strains, in IB-367-pretreated wells, LZD strongly increases its activity. The in vivo studies showed that when CVCs were pretreated with IB-367, Gram-positive biofilm bacterial load was further decreased to 10(1) CFU/mL and bacteremia was not detected., Conclusions: IB-367 has potential as an adjunctive agent to LZD in the treatment of Gram-positive biofilm infections such as CVC infections.

The in vitro activity of the peptide IB-367, alone or combined with either fluconazole (FLU) or amphotericin B (AMB), was investigated against 25 Candida isolates belonging to five species. IB-367 minimum inhibitory concentrations (MICs) ranged from 2.0 to 32 microg/ml and it was active against both FLU-susceptible and - resistant isolates. A rapid fungicidal activity was observed. Synergism was documented in 41.6% and 44% of IB-367/FLU and IB-367/AMB interactions, respectively. Antagonism was never observed. The broad antifungal activity and the positive interactions with AMB and FLU suggest that IB-367 represents a promising candidate against infections due to Candida spp.

Objectives: Various studies suggest that deficiency of magnesium and potassium may be associated with increased risk of ischemic stroke. However, single time-point serum measurements may not be suitable for assessing long-term tissue levels., Patients and Methods: We investigated Mg and K levels in hair of patients with acute ischemic stroke. The elements hair accumulation analysis might provide historical information on their concentrations over a longer period of time and probably reflects the corresponding nutritional condition. The concentrations of Mg and K in hair of 48 men with acute ischemic stroke and a control group were measured using spectroscopic methods., Results: The mean Mg and K concentrations in hair of patients were significantly higher than in the controls., Conclusions: This analysis does not seem to confirm the results of the previous studies suggesting that Mg or K high levels (or their diet supplementation) might protect humans against ischemic stroke.

This study was performed to evaluate the in vitro activity of the amphibian peptide aurein 1.2 and to investigate its interaction with six antibiotics against nosocomial gram-positive cocci. All isolates were inhibited at concentrations of 1 to 16 mg/liter. Synergy was demonstrated when aurein 1.2 was combined with clarithromycin and minocycline.

The in vitro activities of three amphibian peptides magainin II amide, citropin 1.1 and temporin A alone and in combination with eight clinically used antimicrobial agents (imipenem, ceftazidime, clarithromycin, vancomycin, amikacin, polymyxin E, ciprofloxacin and linezolid) were investigated against several multidrug-resistant Pseudomonas aeruginosa and Staphylococcus aureus strains isolated from surgical wound infections. Antimicrobial activities were measured by MIC, MBC and time-kill studies. P. aeruginosa strains were more susceptible to magainin II amide and less susceptible to temporin A. S. aureus isolates were highly susceptible to temporin A and citropin 1.1. The combination studies showed synergy between citropin 1.1 and clarithromycin. Magainin II amide and temporin A showed synergism with imipenem and ceftazidime. Finally, all peptides showed synergistic effects with polymyxin E. These results provide evidence for the potential use of these antimicrobial peptides in the topical or systemic treatment of surgical wound infections.

Background: Morbidity and mortality from staphylococcal toxic shock remain high, despite the availability of antibiotics to which the microorganism is sensitive., Methods: In in vitro experiments, the ability of temporin A to inhibit lipoteichoic acid-induced production of tumor necrosis factor (TNF)- alpha and nitric oxide (NO) was determined. Also, mouse models of staphylococcal sepsis were used to evaluate the efficacy of temporin A alone and in combination with imipenem. BALB/c mice were injected intravenously with live Staphylococcus aureus or heat-killed cells and then received either isotonic sodium chloride solution, 2 mg/kg temporin A, 7 mg/kg imipenem, or 2 mg/kg temporin A in combination with 7 mg/kg imipenem immediately and 6 h after challenge. The main outcome measures were lethality rates, plasma bacterial counts, and plasma TNF- alpha and interleukin (IL)-6 levels., Results: The in vitro experiments showed that temporin A did not cause TNF- alpha or NO release. In the in vivo experiments with live bacteria, both compounds reduced lethality rates and bacterial growth. Imipenem exhibited the highest efficacy. The combination-treated group had significantly lower bacterial counts than did the singly-treated groups and the lowest lethality rates. In the experiments with heat-killed cells, only temporin A demonstrated significant efficacy with respect to lethality and reduction of plasma TNF- alpha and IL-6 levels., Discussion: This study shows that temporin A can reduce the stimulatory effects of bacterial cell components and suggests that it may be beneficial in the treatment of severe staphylococcal sepsis.

The in vitro activity of citropin 1.1 against gram-positive cocci was measured by MIC, minimal bactericidal concentration, time-kill studies, and a checkerboard titration method. Streptococci and staphylococci were inhibited at concentrations between 1 and 16 mg/liter, respectively. Enterococci showed less susceptibility. Synergy was demonstrated when citropin 1.1 was combined with clarithromycin and doxycycline.

To investigate the efficacy of pexiganan, a 22-residue magainin analog, alone and combined with betalactmas antibiotics in three experimental rat models of Gram-negative septic shock. Adult male Wistar rats were given (i) an intraperitoneal injection of 1 mg Escherichia coli 0111:B4 LPS; (ii) 2x10(10)CFU of E. coli ATCC 25922; and (iii) intra-abdominal sepsis induced via cecal ligation and puncture. For each model, all animals were randomized to receive intraperitoneally isotonic sodium chloride solution, 1 mg/kg pexiganan, 1 mg/kg polymyxin B, 20 mg/kg imipenem, 60 mg/kg piperacillin alone and combined with 1 mg/kg pexiganan. Each group included 15 animals. Lethality, bacterial growth in blood or intra-abdominal fluid, endotoxin and TNF-alpha concentrations in plasma. All compounds reduced the lethality when compared to controls. Piperacillin and imipenem significantly reduced the lethality and the number of E. coli in abdominal fluid compared with saline treatment. Pexiganan showed a slightly lower antimicrobial activity than betalactams even though it achieved a substantial higher decrease in endotoxin and TNF-alpha plasma concentrations than imipenem and piperacillin. No statistically significant differences were noted for antimicrobial and antiendotoxin activities between pexiganan and polymyxin B. Combination between pexiganan and betalactams showed to be the most effective treatment in reducing all variables measured. The use of a novel antimicrobial compound able to bind to LPS associated to potent antibiotics such as betalactams may become an important future consideration for sepsis treatment.

The paper describes the effect of 10-, 50-, 100-, 200-, 300-, 400-, and 500-fold excess of low-molecular weight, linear, hexamethyldisiloxane (L(2)) and cyclic hexamethylcyclotrisiloxane (D(3)) with respect to fibrinogen (Fbg) on the conformational stability of Fbg during a 60-h incubation at 37 degrees C. This study used SPE/HPLC/UV and fluorescence of a tryptophan located in the domain of Fbg and fluorescence of 1,1'-bis(4-anilino)naphthalene-5,5'-disulfonic acid (ANS) spectroscopy. The fact that the decrease in fluorescence intensity of siloxane-treated Fbg was accompanied by red shift in the maximum wavelength indicated that denaturation of Fbg had taken place. The differences (the decrease in peak height and the shift in retention time) in chromatograms between control Fbg and siloxane-treated Fbg indicated the adsorption process of Fbg on the surface of siloxanes. Incubating hexamethyldisiloxane with Fbg at L(2)-to-Fbg ratios >300 for 20 h yielded white and mould-like precipitates of Fbg. The same phenomenon demonstrating massive denaturation and aggregation was observed for a greater than 500-fold excess of D(3) with respect to Fbg after 20 h of incubation.

The efficacy of linezolid and temporin A in the prevention of prosthetic graft infection due to methicillin-resistant Staphylococcus epidermidis with intermediate resistance to glycopeptides was investigated in a subcutaneous rat pouch model. Linezolid and temporin A, alone or combined, greatly reduced the bacterial numbers compared to the effect with control drugs.

The in vitro activity of three polycationic peptides, cecropin A, melittin, and cecropin A-melittin hybrid peptide CA(1-7)M(2-9)NH2, alone and in combination with various clinically used antimicrobial agents, was investigated against 32 nosocomial isolates of Acinetobacter baumannii. Antimicrobial activities were measured by MIC, MBC and bacterial killing assay. The peptides demonstrated different ranges of inhibitory values: overall, the organisms were more susceptible to CA(1-7)M(2-9)NH2 (MIC range, 0.25-16 mg/l) than to cecropin A (0.50-32 mg/l) and melittin (0.50-32 mg/l). Synergy was observed when CA(1-7)M(2-9)NH2 and melittin were combined with beta-lactam antibiotics.

Background: The pathomechanism of liver damage in chronic alcoholic liver disease has not been fully elucidated yet. It seems undoubted that one of the mechanisms of alcohol-induced liver damage involves free radical reactions leading to peroxidation of proteins and lipids. The most important defense mechanisms are associated with the activity of antioxidative enzymes, among which glutathione peroxidase (GSH-Px), belonging to so-called 'free radical scavengers' should be mentioned. Selenium, regarded as a bioelement, is present in GSH-Px. Involved in numerous redox reactions, it belongs to the factors protecting the organism from oxidative shock. The aim of the study was to determine the selenium levels in blood serum of chronic alcohol abusers and to find potential correlations with the parameters of liver damage., Material/methods: The study was carried out in a group of 25 subjects (21 males, 4 females), treated in the Clinic or Outpatient Department of Hepatology for chronic alcoholic liver disease. At the time of the study, the patients had abstained from drinking for a period from one month to a year. Selenium was determined with atomic absorption spectroscopy method, using the hydride generation technique. The control group consisted of 11 males and 7 females., Results: Statistical analyses of the control group indicated a significantly higher blood serum selenium level in males than in females. The patients demonstrated elevated aminotransferase activity, normal Falk, markedly increased GGTP. Mean INR was 1.4 and albumin concentration 3.3 g/l. Blood serum selenium levels in male patients were significantly lower in comparison with normal values. The analysis of correlations between some liver function parameters and selenium levels demonstrated a positive correlation between the levels of albumin and selenium. Serum selenium level was inversely proportional to ALAT activity. No correlations between selenium levels and INR levels, or GGTP activity were found., Conclusions: 1. Serum selenium levels differ in male and female populations. In healthy men, the level of Se in the serum is higher. 2. Antioxidative activity measured by serum Se level is low in men with chronic alcoholic liver disease (during the abstinence period). 3. Increased selenium level in the hair may indicate the presence of certain antioxidative reserve, which requires further studies.

Fourier transform (1)H-nuclear magnetic resonance (NMR) spectroscopy was suitable for the quantitative determination of polydimethylsiloxanes (PDMS) in wine and edible oil samples. This approach offers highly specific qualitative and quantitative analysis due to silicone-specific location of proton signals linked to carbon atoms located directly next to silicon atoms (0-0.5 ppm), as well as a different location of signals in the range for different organosilicon structures. The method can be used for the control of PDMS at regulatory limits in foodstuffs (10 mg kg(-1)) using hexamethyldisiloxane (HDMS) as an internal standard. Samples were prepared by extraction under suitable conditions to separate the analyte, and with analyte enrichment before (1)H-NMR analysis. Analytical procedures were developed to permit the determination of PDMS at 0.06 mg kg(-1) in wine and at 6 mg kg(-1) in edible oils samples using readily available NMR instrumentation. It was, however, possible to lower the limit of detection to 6 microg kg(-1) for wine and to 60 microg kg(-1) for edible oils using a higher field instrument (500 MHz). Relative standard deviations (S(r)) were obtained for wine (0.028) and for oil samples (0.043), which when compared with values obtained for samples spiked with PDMS (0.021) indicated that the sample preparation was the main factor determining the precision of the method. The average recovery rates for PDMS were 97 and 95% for wine and edible oils, respectively. PDMS was detected in four brands of Italian wine, with Chianti-Rafaello containing the highest concentration (0.35 mg kg(-1)), and in four types of edible oils, highest concentration (11.9 mg kg(-1)) being found in Italian corn oil. None of the levels of PDMS found in the food samples exceeded the permissible standards laid down by the Codex Alimentarius Commission (10 mg kg(-1)), with the exception of the one corn oil sample.

This paper presents an attempt to assess the total content of silicon and its potentially bioavailable forms to the baby body in milk nutrient and baby foods. The measurements of the total and bioavailable silicon were conducted with the use of two analytical methods. The method of atomic absorption spectroscopy (AAS) was used for the determination of total silicon content. Bioavailable silicon was determined by means of visible light spectroscopy (VIS) with ammonium molybdate. In the group milk products the largest amount of total silicon was found in Mlekovita milk -0.54 mg/l, and Humana 2 milk formula contained the largest amount of ionised silicon-0.24 mg/l. In baby foods manufactured by Gerber the total amount of silicon was high and the average content stood at 27 mg/kg in dry matter. The largest amount of total silicon was found in Vegetables and Ham-48.19 mg/kg in dry matter, as well as bioavailable silicon--4.13 mg/kg in dry matter. Compare level of silicon in milk nutrient and baby foods to silicon content in human milk 0.05 mg/l, it was found that large excess of silicon in this foodstuffs.

Endogenous peptide antibiotics are known as evolutionarily old components of innate immunity. Due to interaction with cell membrane these peptides cause permeabilization of the membrane and lysis of invading microbes. However, some studies proved that antimicrobial peptides are universal multifunctional molecules and their functions extend far beyond simple antibiotics. In this review we present an overview of the general mechanism of action of antimicrobial peptides and discuss some of their additional properties, like antitumour activity, mitogenic activity, role in signal transduction pathways and adaptive immune response.

The objective of these investigations was an in vitro evaluation whether silicone oil OXANE of viscosity 5700 cSt clinically used in eye surgery as a substitute of the vitreous body, being in contact with an artificial polymer lens used as an implant of human lens, causes the changes in its optical properties. The paper presents the results of spectral analysis of transmission of visible (VIS) radiation of three types of artificial lenses: hard PMMA, hydrogel, heparin surface modified (HSM) hard PMMA, and the same lenses damaged by YAG laser radiation with an energy increasing from 1.7 mJ to 3.7 mJ, exposed to clinically applied silicone oil. The studies were carried out, in two-week intervals, over a period of 20 weeks. Hard PMMA and HSM lenses were found not to have changed their optical properties after 20 weeks of exposure to silicone oil. The measured transmittance values were within the range of instrumental error (+/- 1%). Optical properties of hydrogel lenses exposed to silicone oils deteriorated with exposure and after 20-week exposure to silicone oil the average transmittance value decreased by about 18%, reaching its final value of 67.08 +/- 2.37% (RSD = 5.56%). A minimal decrease of the initial transmittance values was observed only for the lenses exposed to laser radiation of highest energy (3.7 mJ). After completed exposure to silicone oil, two kinds of lenses were found to have a slightly improved transmittance: hard PMMA lenses by about 4% and HSM lenses by about 2%. On the other hand, in case of hydrogel lenses the deterioration of optical properties to the extent comparable to that of hydrogel lenses not damaged by laser radiation was observed.

The object of the publication is the presentation of data referring to in vivo silicones biodegradation and their potential clinical and molecular consequences. Summing up, one needs to state that the products of silicones biodegradation are not biologically indifferent. In particular, different types of silanols are inhibitors of proteolytic enzymes and regulators of many metabolic processes as well as affect the cell growth and division, which distinctly indicates the potentially strong pharmacological action. The main objective of the molecular consequences of the biodegradation of siloxanes was the verification what impact siloxanes of various molecular weights and of various chain lengths exert on the conformational stability of biological molecules.

The spectrophotometric method based on the reaction of formation of silic-molybdenum blue for determination of silica (silicon dioxide) in hydrogenated fat was developed. Determination limit of silica in this method was 15.6 mg/kg and average recovery 77.77%. Using this method the content of silica in the edible fat (margarine) taken from the market was determined. The samples of margarine before determination of silicon dioxide were mineralised and than the analyte was concentrated. The silica was not found in the margarine samples at levels above the determination limit of spectrophotometric method i.e. 15.6 mg/kg.