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Dive into the research topics where Ryszard Kocjan is active.

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Featured researches published by Ryszard Kocjan.


Talanta | 2014

Application of solid phase extraction with the use of silica modified with polyaniline film for pretreatment of samples from plant material before HPLC determination of triterpenic acids

Ireneusz Sowa; Magdalena Wójciak-Kosior; Kamila Rokicka; Ryszard Kocjan; Grażyna Szymczak

The new sorbent based on silica gel coated with a film of polyaniline (Si-PANI) was obtained in a process of in situ polymerization directly on carrier particles and its potential application for pretreatment of plant material samples with the use of solid phase extraction (SPE) was investigated. Parameters such as cartridge conditioning, the volume and concentration of the sample, the type and volume of the elution solvent were optimized and compared with parameters obtained for RP-18 and aminopropyl silica cartridges. The high recovery values above 97% after the SPE procedure with the use of Si-PANI cartridges proves their utility for analysis of triterpenic acids. The sorbent tested was successfully used for clean-up of extracts from Salvia officinalis L., Syzygium aromaticum (L.) Merrill., and Origanum vulgare L. prior to HPLC-DAD determination of oleanolic, ursolic and betulinic acid. The efficiency of sample purification was verified by monitoring of chromatograms in the region between 190 nm and 400 nm during the gradient elution. The fewest components or their lowest concentrations were observed for all the investigated samples after the SPE procedures.


Journal of Trace Elements in Medicine and Biology | 2015

Serum and urinary selenium levels in obese children: a cross-sectional study

Anna Błażewicz; Maria Klatka; Aleksander Astel; Izabela Korona-Glowniak; Wojciech Dolliver; Wojciech Szwerc; Ryszard Kocjan

OBJECTIVE To determine serum and urinary selenium (Se) levels in children with and without obesity, and to assess if Se influences the risk of obesity. SUBJECTS AND METHODS High-resolution-continuum source-atomic absorption spectrometry (HR-CS-AAS) was used to determine the content of Se in 80 children (age 6-17; 40 boys, 40 girls). Correlations between variables were tested with the use of Spearmans correlation coefficient. U Mann-Whitney test was applied to assess the difference of Se contents in samples. Measured metabolic risk factors (blood pressure, glucose level, triglycerides (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and total cholesterol), age, gender, and BMI were correlated. Logistic regression models were fitted to identify predictors of obesity interacting with selenium content in serum and urine, separately. RESULTS Obese children, regardless of gender, had lower Se content. Se level in serum (p=0.001, OR 0.74, 95%CI 0.62-0.88) and total cholesterol (p=0.001, OR 1.19, 95%CI 1.08-1.31) were the independent factors significantly influencing the risk of obesity in children. Two separate models were observed for Se in urine: (i) Se level (p<0. 0001, OR 0.70, 95%CI 0.58-0.84) and glucose level (p<0.0001, OR 1.22, 95%CI 1.10-1.35), and (ii) Se level (p=0.002, OR 0.60 95%CI 0.43-0.83) and total cholesterol level (p=0.003, OR 1.16, 95%CI 1.05-1.28). CONCLUSION The current study suggests a possible role of Se in obesity. Further research needs to be performed to check if obese children are an at-risk group for Se deficiency.


Talanta | 2013

Physicochemical properties of silica gel coated with a thin layer of polyaniline (PANI) and its application in non-suppressed ion chromatography

Ireneusz Sowa; Ryszard Kocjan; Magdalena Wójciak-Kosior; Ryszard Świeboda; Dominika Zajdel; M. Hajnos

Physicochemical properties of a new sorbent and its potential application in non-suppressed ion chromatography (IC) have been investigated. The sorbent was obtained in a process of covering silica gel particles with a film of polyaniline (PANI). The properties of silica modified with polyaniline such as particle size, porosity, average quantity of polyaniline covering carrier and density of sorbent were determined. In our study the following methods were used: microscopic analysis, laser diffraction technique, combustion analysis, mercury porosimetry and helium pycnometry. Column with the newly obtained packing was used for the separation of inorganic anions. Optimized chromatographic system was successfully employed for analysis of iodide and bromide in selected pharmaceutical products (Bochnia salt and Iwonicz salt) applied in chronic respiratory disease. Analysis was carried out using 0.1M solution of HCl in mixture of methanol/water (50:50v/v) as a mobile phase; the flow rate was 0.3 mL min(-1), temperature was 24°C and λ=210 nm. Validation parameters such as correlation coefficient, RSD values, recovery, detection and quantification limits were found to be satisfactory.


Journal of Chromatography B | 2014

Determination of total iodine in serum and urine samples by ion chromatography with pulsed amperometric detection - studies on analyte loss, optimization of sample preparation procedures, and validation of analytical method.

Anna Błażewicz; Maria Klatka; Wojciech Dolliver; Ryszard Kocjan

A fast, accurate and precise ion chromatography method with pulsed amperometric detection was applied to evaluate a variety of parameters affecting the determination of total iodine in serum and urine of 81 subjects, including 56 obese and 25 healthy Polish children. The sample pretreatment methods were carried out in a closed system and with the assistance of microwaves. Both alkaline and acidic digestion procedures were developed and optimized to find the simplest combination of reagents and the appropriate parameters for digestion that would allow for the fastest, least time consuming and most cost-effective way of analysis. A good correlation between the certified and the measured concentrations was achieved. The best recoveries (96.8% for urine and 98.8% for serum samples) were achieved using 1ml of 25% tetramethylammonium hydroxide solution within 6min for 0.1ml of serum/urine samples. Using 0.5ml of 65% nitric acid solution the best recovery (95.3%) was obtained when 7min of effective digestion time was used. Freeze-thaw stability and long-term stability were checked. After 24 weeks 14.7% loss of iodine in urine, and 10.9% in serum samples occurred. For urine samples, better correlation (R(2)=0.9891) of various sample preparation procedures (alkaline digestion and application of OnGuard RP cartidges) was obtained. Significantly lower iodide content was found in samples taken from obese children. Serum iodine content in obese children was markedly variable in comparison with the healthy group, whereas the difference was less evident when urine samples were analyzed. The mean content in serum was 59.12±8.86μg/L, and in urine 98.26±25.93 for obese children when samples were prepared by the use of optimized alkaline digestion reinforced by microwaves. In healthy children the mean content in serum was 82.58±6.01μg/L, and in urine 145.76±31.44μg/L.


Analytica Chimica Acta | 2013

Synthesis and properties of a newly obtained sorbent based on silica gel coated with a polyaniline film as the stationary phase for non-suppressed ion chromatography

Ireneusz Sowa; Magdalena Wójciak-Kosior; Piotr Drączkowski; Maciej Strzemski; Ryszard Kocjan

The new sorbent for non-suppressed ion chromatography based on silica gel coated with a film of polyaniline (PANI) was obtained in a process of in situ polymerization of aniline by oxidation with ammonium peroxydisulfate. Raman analyses performed using a Thermo Scientific DXR confocal Raman Microscope equipped with the Omnic 8 software from Thermo Fisher Scientific have proved a uniform distribution of PANI on the surface of chromatographic beads and in the pores of the particle. The obtained stationary phase was packed into a stainless steel HPLC column. The quality of the prepared column was verified on the basis of hydrodynamic parameters such as column efficiency index (Ip) and separation impedance (E). The potential application of silica gel modified with polyaniline for separation and determination of selected anions using non-suppressed ion chromatography was also investigated. Chromatographic analyses were performed using of the ion chromatograph Dionex DX-500. The best results were obtained for the mobile phase consisting of an aqueous or methanolic solution of hydrochloric acid. The tested column and optimized chromatographic system were successfully used for the analysis of nitrate, bromide and iodide in waters samples.


BioMed Research International | 2017

Alterations of Hair and Nail Content of Selected Trace Elements in Nonoccupationally Exposed Patients with Chronic Depression from Different Geographical Regions

Anna Błażewicz; Kuan-Yung Liao; Heng-Hsin Liao; Przemysław Niziński; Łukasz Komsta; Berislav Momčilović; Magdalena Jabłońska-Czapla; Andrzej Prystupa; Jarosław Sak; Ryszard Kocjan

The aim of this study was to determine if altered levels of selected trace elements manifest themselves during chronic depression. To identify elements strongly associated with chronic depression, relationships between the elemental contents of hair and nails and the interelement correlations were checked. Inductively coupled plasma mass spectrometry and ion chromatography were used to evaluate the contents of Zn, Cu, Co, Pb, Mn, and Fe in hair and nail samples from a total of 415 subjects (295 patients and 120 healthy volunteers). The study included logistic regression models to predict the probability of chronic depression. To investigate possible intercorrelations among the studied elements, the scaled principal component analysis was used. The research has revealed differences in TE levels in the group of depressed men and women in comparison to the healthy subjects. Statistically significant differences in both hair and nails contents of several elements were observed. Our study also provides strong evidence that the intermediary metabolism of certain elements is age- and gender-dependent. Zn, Mn, Pb, and Fe contents in hair/nails seem to be strongly associated with chronic depression. We found no statistically significant residence-related differences in the contents of studied elements in nonoccupationally exposed patients and healthy subjects.


Journal of Agricultural and Food Chemistry | 2014

Biofortification of soy (Glycine max (L.) Merr.) with strontium ions.

Ireneusz Sowa; Magdalena Wójciak-Kosior; Maciej Strzemski; Sławomir Dresler; Wojciech Szwerc; Tomasz Blicharski; Grażyna Szymczak; Ryszard Kocjan

Soy (Glycine max (L.) Merr.) is an annual plant cultivated worldwide mostly for food. Moreover, due to its pharmacological properties it is widely used in pharmacy for alleviating the symptoms of osteoporosis. The aim of the present study was to investigate the biofortification of soy treated with various concentrations of strontium. Soy was found to have a strong capacity to absorb Sr(2+) (bioconcentration factor higher than 1). A positive linear correlation (R(2) > 0.98) between the amount of strontium in the growth medium and its content in the plant was also observed. Moreover, at a concentration of 1.5 mM, strontium appeared to be nontoxic and even stimulated plant growth by approximately 19.4% and 22.6% of fresh weight for shoots and roots, respectively. Our research may be useful to obtain vegetable products or herbal preparations containing both phytoestrogens and strontium to prevent postmenopausal osteoporosis.


Natural Product Research | 2018

Proliferative and antioxidant activity of Symphytum officinale root extract

Ireneusz Sowa; Roman Paduch; Maciej Strzemski; Sylwia Zielińska; Ewelina Rydzik-Strzemska; Jan Sawicki; Ryszard Kocjan; Janusz Polkowski; Adam Matkowski; Michał Latalski; Magdalena Wójciak-Kosior

Abstract The root of Symphytum officinale L. is commonly used in folk medicine to promote the wound healing, reduce the inflammation and in the treatment of broken bones. The objective of our investigation was to analyse the extract from S. officinale in term of its antioxidant activity and the effect on cell viability and proliferation of human skin fibroblast (HSF). Moreover, the quantification of main phenolics and allantoin was conducted using HPLC–DAD method. Five compounds were found: rosmarinic, p-hydroxybenzoic, caffeic, chlorogenic and p-coumaric acid. DPPH, FRAP and TPC assay showed the high antioxidant activity of the extract. MTT test proved the stimulatory effect on cell metabolism and viability of HSF cells. Moreover, no changes in cytoskeleton structure and cells shape were observed. The obtained results indicate that non-toxic extract from S. officinale root has strong antioxidant potential and a beneficial effect on human skin fibroblasts.


Molecules | 2016

The Stimulatory Effect of Strontium Ions on Phytoestrogens Content in Glycine max (L.) Merr

Magdalena Wójciak-Kosior; Ireneusz Sowa; Tomasz Blicharski; Maciej Strzemski; Sławomir Dresler; Grażyna Szymczak; Artur Wnorowski; Ryszard Kocjan; Ryszard Świeboda

The amount of secondary metabolites in plants can be enhanced or reduced by various external factors. In this study, the effect of strontium ions on the production of phytoestrogens in soybeans was investigated. The plants were treated with Hoagland’s solution, modified with Sr2+ with concentrations ranging from 0.5 to 3.0 mM, and were grown for 14 days in hydroponic cultivation. After harvest, soybean plants were separated into roots and shoots, dried, and pulverized. The plant material was extracted with methanol and hydrolyzed. Phytoestrogens were quantified by HPLC. The significant increase in the concentration of the compounds of interest was observed for all tested concentrations of strontium ions when compared to control. Sr2+ at a concentration of 2 mM was the strongest elicitor, and the amount of phytoestrogens in plant increased ca. 2.70, 1.92, 3.77 and 2.88-fold, for daidzein, coumestrol, genistein and formononetin, respectively. Moreover, no cytotoxic effects were observed in HepG2 liver cell models after treatment with extracts from 2 mM Sr2+-stressed soybean plants when compared to extracts from non-stressed plants. Our results indicate that the addition of strontium ions to the culture media may be used to functionalize soybean plants with enhanced phytoestrogen content.


Journal of Trace Elements in Medicine and Biology | 2016

Iodine in autism spectrum disorders.

Anna Błażewicz; Agata Makarewicz; Izabela Korona-Glowniak; Wojciech Dolliver; Ryszard Kocjan

OBJECTIVE The aim of our study was to assess the iodine status of Polish boys with severe autism compared to their healthy peers and evaluate the relationship between urinary iodine, thyroid hormones, body mass index and Autism Spectrum Disorder (ASD) symptomatology. SUBJECTS AND METHODS Tests were performed in 40 boys with ASD and 40 healthy boys, aged 2-17 from the same geographic region in Poland. Urinary iodine (UI), free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), BMI, and individual symptoms measured by the Childhood Autism Rating Scale (CARS) were correlated. Validated ion chromatography method with pulsed amperometric detection was applied for the determination of urinary iodine after optimized alkaline digestion in a closed system assisted with microwaves. RESULTS 19 out of 40 children with ASD had mild to moderate iodine deficiency. Statistically significant lower levels of UI, fT3 and fT4 and higher levels of TSH were found in the autistic group when compared with the control group. Concentration of iodine in urine was negatively associated with clinicians general impression for children between 11 and 17 years. Emotional response, adaptation to environmental change, near receptor responsiveness, verbal communication, activity level, and intellectual functioning are more associated with UI than other symptoms listed in CARS. CONCLUSION The severity of certain symptoms in autism is associated with iodine status in maturing boys. Thyroid hormones were within normal reference ranges in both groups while urinary iodine was significantly lower in autistic boys suggesting that further studies into the nonhormonal role of iodine in autism are required.

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Ireneusz Sowa

Medical University of Lublin

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Maciej Strzemski

Medical University of Lublin

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Wojciech Szwerc

Medical University of Lublin

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Eliza Blicharska

Medical University of Lublin

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Anna Błażewicz

Medical University of Lublin

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Grażyna Szymczak

Maria Curie-Skłodowska University

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Jan Sawicki

Medical University of Lublin

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Sławomir Dresler

Maria Curie-Skłodowska University

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Łukasz Komsta

Medical University of Lublin

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