Effect of Low Doses of Guaiacol and Ethanol on Enzymatic Activity of Fungal Cultures

The influence of low doses of guaiacol and ethanol, the natural effectors of lignin and phenolics transformations, on laccase and peroxidase activities produced by two strains of Basidiomycetes, Pleurotus sajor-caju and Trametes versicolor, was evaluated. Fungal mycelia were grown for 2 weeks on liquid media containing serial dilutions of guaiacol or ethanol ranging from 100−1 to 100−20 mol/L. Laccase and peroxidase activities in the medium were measured at the end of 2 weeks. The effect of low doses of guaiacol and ethanol on enzyme activities was manifested in an oscillating manner. Similar response patterns were observed when pure enzymes were exposed to the same serial dilutions of guaiacol and ethanol. T. versicolor cultures enriched with 40 mmol guaiacol (simulating natural environmental conditions) also displayed oscillating enzyme activity patterns in response to serial dilutions of guaiacol, but the maximum enzyme activity values were increased compared to those observed in cultures not receiving 40 mmol guaiacol. The differences between maxima and minima varied among the experimental groups and depended on the species of fungus, type of effector, and kind of enzyme. The results suggests the possibility of subtle regulation of enzymatic activity on the molecular level

Nonlinear changes in the activity of the oxygen-dependent demethylase system in Rhodococcus erythropolis cells in the presence of low and very low doses of formaldehyde

The effect of exogenous, highly diluted formaldehyde on the rate of demethylation/re-methylation of veratric acid by the bacteria Rhodococcus erythropolis was studied using electrophoretic and microscopic techniques. The activity of 4-O-demethylase, responsible for accumulation of vanillic acid, and the levels of veratric and vanillic acids were determined using capillary electrophoresis. Formaldehyde was serially diluted at 1:100 ratios, and the total number of iterations was 20. After incubation of the successive dilutions of formaldehyde with the bacteria, demethylase activity oscillated in a sinusoidal manner. It was established using capillary electrophoresis that methylation of vanillic acid to veratric acid occurred at a double rate, as shown by the doubled fluctuation in the concentration of veratrate. There were also changes in the NADH oxidase activity, which is associated with methylation processes. Microscopic observations revealed the presence of numerous enlarged vacuoles in bacterial cells during the accumulation of large amounts of vanillic acid, and their disappearance together with a decrease in 4-O-demethylase activity. The presented results give evidence for the ability of living cells to detect the presence of submolecular concentrations of biological effectors in their environment and provide a basis for a scientific explanation of the law of hormesis and the therapeutic effect of homeopathic dilutions

Testy agregometrii optycznej w diagnostyce trombocytopatii

Zaburzenia funkcji płytek krwi (PFD) to rzadko występująca, a zarazem heterogenna grupachorób należących do skaz krwotocznych. Kompleksowa diagnostyka nieprawidłowej funkcjipłytek krwi (PLT), tzw. trombocytopatii — wymaga zastosowania specjalistycznych badań. Złotymstandardem diagnostyki PFD jest agregometria optyczna oparta na pomiarze światła widzialnego(LTA). Do próbki badanego osocza bagatopłytkowego dodawany jest w odpowiednimstężeniu określony agonista agregacji PLT (ADP, kwas arachidonowy, kolagen, rystocetyna,epinefryna). Na skutek interakcji z agonistą dochodzi do aktywacji i następczej agregacji płytekkrwi. Powstawaniu agregatów płytkowych towarzyszy proporcjonalny wzrost przepuszczalnościświatła. W pracy przedstawiono zasadę metody LTA wraz z omówieniem podstawowego paneluagonistów agregacji płytek krwi. Ponadto scharakteryzowano mocne strony metody LTAi ograniczenia oraz porównano ją z pozostałymi alternatywnymi metodami diagnostyki PFD

The Influence of Very Low Doses of Cisplatin on Tumor Cell Proliferation In Vitro and on Some Hematological and Enzymatic Parameters of Healthy Rats

Healthy rats had been treated for 2 or 6 weeks with 1.0 mL of 10-8 and 10-16 mg/mL of cisplatin. After 2 weeks of treatment, a significant increase in leukocyte and erythrocyte count and also in hematocrit was observed. Among leukocytes the number of neutrophils and eosinophils significantly increased. Biochemical analyses indicated a decrease in the glycogen content in the liver and kidneys after 2 weeks of treatment with low doses of cisplatin but at the end of the experiment (8th week of experiment) the stores of glycogen increased significantly. Biochemical analyses concerning the activity of some enzymes in the liver revealed a significant increase of peroxidase and acid phosphatase as well as catalase activities after 2 weeks of treatment. However, catalase was induced by a very low concentration of cisplatin, 10-16 mg/mL. After the cessation of cisplatin treatment the activity of enzymes returned to normal values. Human lung carcinoma cell line A549 (ECACC No 86012804) was also studied after treatment with the same doses of cisplatin and inhibition of its growth was observed. The results of these experiments strongly indicated that low doses of cisplatin could be stimulating for healthy cells but cytostatic for tumor cells. Possible mechanisms involved in the biological activity of very low cisplatin concentrations are discussed

Light transmission aggregometry in the diagnosis of thrombocytopathy

Platelet function disorders (PFD) are a rare and heterogeneous group of hemorrhagic diathesis. Comprehensive diagnostics of impaired platelet function (PLT) — the so called thrombocytopathy — requires the use of special testing. The gold standard for measurement/diagnostics of platelet function disorders is light transmission aggregometry (LTA). A platelet agonist (ADP, arachidonic acid, collagen, ristocetin, epinephrine) is added at an appropriate concentration to the sample of platelet-rich plasma. The interaction with the agonist leads to platelet activation and subsequent platelet aggregation. Aggregate formation is accompanied by a corresponding increase in light transmission. This review presents the principle of the LTA method, and a discussion of the basic panel of platelet aggregation agonists. In addition, the strengths and limitations of the LTA method are characterized and the method is compared with other alternative methods of PFD diagnostics

Application of the SMALP technology to the isolation of GPCRs from low-yielding cell lines

The ability of styrene–maleic acid (SMAc) co-polymers to spontaneously insert into biological membranes can be exploited to extract G protein-coupled receptors (GPCRs) embedded in styrene–maleic acid lipid particles (SMALPs), preserving the native environment around the protein and thus enhancing the feasibility of functional studies. So far, the SMALP technology has been primarily employed on non-mammalian cells and protocols are not optimized for adherent human cell lines, which cannot be harvested in large amounts. In this work, a fine investigation of key parameters affecting the formation of SMALPs was undertaken with the purpose of maximizing the yield of extraction of a recombinant form of human β2-adrenergic receptor (rhβ2AR) from HEK293T cells. The study highlighted an important influence of ionic strength on the membrane solubilization efficiency and GPCR purification yield of SMAc co-polymers: by lowering the salt concentration of all buffers used in previously published SMALP protocols, the water solubility and extraction efficiency of the selected SMAc co-polymer (commercially supplied as a potassium salt) were enhanced. In-line combination of size-exclusion chromatography (SEC) with immobilized metal affinity chromatography (IMAC) allowed further improvement of the final rhβ2AR yield by reducing the loss of SMALP-embedded GPCRs during the fractionation and purification of SMALPs. The overall findings of this study show that the available SMALP protocols can be significantly optimized in several aspects in order to increase the efficiency of GPCR solubilization and isolation from low-yielding expression systems

Massive pulmonary embolism treated successfully with embolectomy following failed thrombolysis : the role of repeated spiral computerised tomography and echocardiography : a case report

A case of a 29-year-old male with massive pulmonary embolism is presented. The diagnosis was confirmed by spiral computerised tomography and echocardiography. The patient received streptokinase, but he continued to be in cardiogenic shock without any improvement. Repeated tomography and echocardiography revealed progression of pulmonary embolism. The patient was transferred to a cardiosurgical department where successful embolectomy was performed

Influence of very low doses of mediators on fungal laccase activity - nonlinearity beyond imagination

Laccase, an enzyme responsible for aerobic transformations of natural phenolics, in industrial applications requires the presence of low-molecular substances known as mediators, which accelerate oxidation processes. However, the use of mediators is limited by their toxicity and the high costs of exploitation. The activation of extracellular laccase in growing fungal culture with highly diluted mediators, ABTS and HBT is described. Two high laccase-producing fungal strains, Trametes versicolor and Cerrena unicolor, were used in this study as a source of enzyme. Selected dilutions of the mediators significantly increased the activity of extracellular laccase during 14 days of cultivation what was distinctly visible in PAGE technique and in colorimetric tests. The same mediator dilutions increased demethylation properties of laccase, which was demonstrated during incubation of enzyme with veratric acid. It was established that the activation effect was assigned to specific dilutions of mediators. Our dose-response dilution process smoothly passes into the range of action of homeopathic dilutions and is of interest for homeopaths

Long QT syndrome in the postpartum period

The postpartum period can unmask LQTS. We described a case of 22-year-old woman with episode of lost of consciousness 6 months after delivery. Holter monitoring showed episodes of QTc prolongation, max. QTc – 618 ms, medium QTc – 538 ms with different morphology types of T wave. Beta-blocker (BB) therapy (metoprolol was initiated) and titrated up to 200 mg daily. The patient was out of symptoms. After 2 years during the second pregnancy she reduced BB to 50 mg/day. In the postpartum period, 3 months after delivery she had syncopal episodes. Holter monitoring showed polymorphic ventricular tachycardia. The cardioverter-defibrillator was implanted