Parathion-methyl – determination metod

Metoda polega na pobraniu zawartego w powietrzu parationu metylowego na sorbent – żel krzemionkowy z chemicznie związaną fazą oktadecylową (ODS-C18) i ekstrakcji substancji z sorbentu eterem dietylowym. Suchą pozostałość po odparowaniu eteru rozpuszcza się w cykloheksanie. Paration metylowy oznacza się w otrzymanym roztworze metodą chromatografii gazowej z detektorem azotowo- -fosforowym (NPD) na kolumnie kapilarnej. Najmniejsze stężenie parationu metylowego, jakie można oznaczać podaną metodą, wynosi 0,025 mg/m3.This method is based on the adsorption of parathion-methyl vapours on silica gel with chemically bounded octadecyl phase ODS-C18, extraction of the compound with diethyl ether and then determination in the obtained solution by capillary gas chromatography (GC-NPD). The determination limit of this method is 0.025 mg/m3

Selection of Sorption Material for Tests of Pesticide Permeation Through Protective Clothing Fabrics

The paper presents the results of studies on selecting a solid sorption material for absorbing liquid crop protection agents which permeate samples of protective clothing fabrics. The sorption materials were investigated and selected with an assumption that they should have a high recovery coefficient for biologically active substances, used as active ingredients in crop protection agents, at a presumed, acceptably high level. The selected substances were determined with a gas chromatograph equipped with an electron capture detector (dichlorvos, cypermethrin and 2,4-D) and a nitrogen-phosphorus detector (carbofuran). The tests demonstrated that polypropylene melt-blown type unwoven cloth had high recovery coefficients for all 4 active ingredients proposed for the study. The highest recovery coefficient, -.97, was obtained for carbofuran. The recovery coefficients obtained for the 3 remaining substances were lower: .89 for cypermethrin and 2,4-D, and .84 for dichlorvos

Scientific co-operation with professor Nazimek

In present paper there will be discussed examples of author's scientific co-operation with professor Nazimek. Generally all of them are from the area of heterogeneous catalysis including high dispersed metal phase mostly in the hydrogenolysis reactions of simple alkanes

Pesticide content in drinking water samples collected from orchard areas in Central Poland

Samples of drinking water collected in Warka-Grójec region of central Poland were tested for the presence of pesticides. Data obtained from analysis of water samples will be used for future epidemiological and environmental studies in the region. Samples were collected during spring and autumn of 2002-2003 from dug wells, deep wells and water mains in 81 randomly-selected rural households scattered throughout this region of extensive agriculture. The concentration of pesticides from four main chemical groups was determined by gas chromatography: organochlorines (lindane, DDT, methoxychlor), triazines (atrazine, simazine), organophosphates (acephate, diazinon, fenitrothion) and pyrethroids (alpha-cypermethrin, deltamethrin). Two-year monitoring of drinking water samples indicated the presence of DDT and methoxychlor contamination. Pyrethroids were generally not detected, with the exception of alpha-cypermethrin found in only a few samples. Triazines were also found in water samples collected in the course of the study with higher incidence during spring period. Organophosphates were by far the most common contaminants of drinking water in this region. Almost all samples were contaminated by signifi cant amounts of fenitrothion. The present study reveals an urgent need for systematic monitoring of drinking water quality in regions of intensive agriculture, since they are highly vulnerable to pesticide contamination. Consumption of pesticide-contaminated water may have a negative impact on the population living in this area, which also requires scientifi c assessment

Antibodies Enhance the Suppressive Activity of Extracellular Vesicles in Mouse Delayed-Type Hypersensitivity

Previously, we showed that mouse delayed-type hypersensitivity (DTH) can be antigen-specifically downregulated by suppressor T cell-derived miRNA-150 carried by extracellular vesicles (EVs) that target antigen-presenting macrophages. However, the exact mechanism of the suppressive action of miRNA-150-targeted macrophages on effector T cells remained unclear, and our current studies aimed to investigate it. By employing the DTH mouse model, we showed that effector T cells were inhibited by macrophage-released EVs in a miRNA-150-dependent manner. This effect was enhanced by the pre-incubation of EVs with antigen-specific antibodies. Their specific binding to MHC class II-expressing EVs was proved in flow cytometry and ELISA-based experiments. Furthermore, by the use of nanoparticle tracking analysis and transmission electron microscopy, we found that the incubation of macrophage-released EVs with antigen-specific antibodies resulted in EVs’ aggregation, which significantly enhanced their suppressive activity in vivo. Nowadays, it is increasingly evident that EVs play an exceptional role in intercellular communication and selective cargo transfer, and thus are considered promising candidates for therapeutic usage. However, EVs appear to be less effective than their parental cells. In this context, our current studies provide evidence that antigen-specific antibodies can be easily used for increasing EVs’ biological activity, which has great therapeutic potential.</jats:p

Expression of activation-induced cytidine deaminase enhances the clearance of pneumococcal pneumonia : evidence of a subpopulation of protective anti-pneumococcal B1a cells

We describe a protective early acquired immune response to pneumococcal pneumonia that is mediated by a subset of B1a cells. Mice deficient in B1 cells (xid), or activation‐induced cytidine deaminase (AID (−/−)), or invariant natural killer T (iNKT) cells (Jα18 (−/−)), or interleukin‐13 (IL‐13 (−/−)) had impaired early clearance of pneumococci in the lung, compared with wild‐type mice. In contrast, AID (−/−) mice adoptively transferred with AID (+/+) B1a cells, significantly cleared bacteria from the lungs as early as 3 days post infection. We show that this early bacterial clearance corresponds to an allergic contact sensitivity‐like cutaneous response, probably due to a subpopulation of initiating B1a cells. In the pneumonia model, these B1a cells were found to secrete higher affinity antigen‐specific IgM. In addition, as in contact sensitivity, iNKT cells were required for the anti‐pneumococcal B1a cell initiating response, probably through early production of IL‐13, given that IL‐13 (−/−) mice also failed to clear infection. Our study is the first to demonstrate the importance of AID in generating an appropriate B1a cell response to pathogenic bacteria. Given the antibody affinity and pneumonia resistance data, natural IgM produced by conventional B1a cells are not responsible for pneumonia clearance compared with the AID‐dependent subset