Wyniki wyszukiwania

1

Przekazywanie energii w jednostkach fotosytetycznych

100%

Frackowiak D., Fiksinski K.

Postępy Biochemii

|

1976

|

tom 22

|

nr 4

2

Spectral properties of cyanobacteria adapted to green and red light

100%

Frackowiak D., Planner A.

Acta Physiologiae Plantarum

|

1995

|

tom 17

|

nr 2

3

Opóźniona luminescencja fikobilistów

81%

Frackowiak D., Planner A., Dudkowiak A.

Current Topics in Biophysics. Supplement

|

1992

|

tom 16

4

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Wpływ matrycy ciekłokrystalicznej na polaryzację widm bakteriochlorofilu a i chlorofilu c

81%

Bauman D., Frackowiak D., Wrobel D.

Zeszyty Problemowe Postępów Nauk Rolniczych

|

1984

|

nr 271

5

The comparison of excitation energy transfer processes in phycobilisomes from Anabaena variabilis and Anabaena azollae

81%

Frackowiak D., Dudkowiak A., Erokhina L. G., Leblanc R. M.

Acta Physiologiae Plantarum

|

1991

|

tom 13

|

nr 3

6

Incorporation of stilbazolium merocyanines into human leukocytes measured by flow cytometry

81%

Wiktorowicz K., Niedbalska M., Planner A., Frackowiak D.

Acta Biochimica Polonica

|

1995

|

tom 42

|

nr 3

Human peripheral blood leukocytes were incubated with thirteen various merocyanines of the stilbazolium betaine type and the fluorescence intensities of the cells were measured by flow cytometry. The fluorescence intensity of lymphocytes, monocytes and granulocytes depended on the time and temperature of incubation with the dyes. An increase in the incubation temperature enhanced the fluorescence intensity whereas washing of the cells after incubation had little influence on the observed emission. This points to incorporation of the dye molecules into the cell membrane. From the measured fluorescence intensities corrected for relative fluorescence yields, the relative efficiencies of incorporation into the cells of the various merocyanines tested were evaluated. The efficiency was dependent on the type of the cells and the length and side groups of the merocyanine molecules studied.

7

Effect of chromatic adaptation of spectral properties and orientation of complexes and on energy transfer in cyanobacteria Tolypothrix cells embedded in skew stretched poly[vinyl alcohol] films

81%

Frackowiak D., Zelent B., Skibinski A., Leblanc R. M.

Acta Physiologiae Plantarum

|

1993

|

tom 15

|

nr 3

8

The incorporation of various porphyrins into blood cells measured via flow cytometry, absorption and emission spectroscopy

81%

Ion R. M., Planner A., Wiktorowicz K., Frackowiak D.

Acta Biochimica Polonica

|

1998

|

tom 45

|

nr 3

The incorporation of the five following porphyrins: meso-tetra(4-phenyl)porphyrin (TPP); meso-tetra(4-sulfonato-phenyl)porphyrin (TPPS4); meso-tetra(4-naphthyl)porphyrin (TNP); tri-sulfo-tetra-phenyl porphyrin (TPPS3) and tetra-sulfonato-naphthyl porphyrin (TNPS4) into human blood cells was investigated using flow cytometry, and absorption and emission spectroscopy. The percentage of stained cells, measured in a fluorescence cytometer, provided information on the efficiency of incorporation of fluorescent dye molecules into different types of cells. The yield of the incorporation of a dye was dependent on the type of dye and the solvent used for cell incubation. The degree of dye aggregation and ionization varied with the incubation medium, but dye molecules incorporated into cells seemed to be restricted to those in the monomeric state, exhibiting similar fluorescence yield. Of the three sulfonated porphyrins investigated only TPPS4 was efficiently incorporated into leukocytes. In the incubation solvent, this dye was in monomeric and neutral form. TPPS3 which was also in monomeric form, practically was not incorporated into cells. TPP and TNP dissolved in 5% aqueous dimethyl sulfoxide were present mostly in aggregated forms but they penetrated the cells with high efficiency. The results obtained seem to indicate that porphyrins are promising candidates for application in phytodynamic therapy.

9

Spectral properties of phthalocyanines incorporated into resting and stimulated human peripheral blood cells

81%

Waszkowiak A., Frackowiak D., Wiktorowicz K., Miyake J.

Acta Biochimica Polonica

|

2002

|

tom 49

|

nr 3

Human peripheral blood cells stimulated by phytohemagglutinin (which serve as a model of cancerous cells) and resting cells were incubated in dimethyl sulfoxide solutions of various phthalocyanines. In order to diminish the influence of atmospheric oxygen the cells were embedded in a polymer (polyvinyl alcohol) film. Fluorescence spectra of the samples were measured over two regions of excitation wavelengths: at 405 nm (predominant absorption of the cell material) and in the regions of strong absorption of phthalocyanines (at about 605 nm and 337 nm). The intrinsic emission of cell material became changed as a result both of cells' stimulation and of incubation of cells in dye solution. In most cases the stimulated cells when stained by dye exhibited higher long wavelength fluorescence intensity than resting cells. This suggests higher efficiency of dye incorporation into cancerous cells than into healthy cells. The absorption spectra of samples were also measured. The spectra of various phthalo- cyanines in incubation solvent, in polymer and in the cells embedded in polymer, were compared. The comparison of properties of the cells stimulated for different time periods enabled to establish the conditions of stimulation creating a population of cells incorporating a large number of sensitizing molecules.

10

Agregacja chlorofilu w układach modelowych

71%

Goc J., Frackowiak D., Niedbalska M., Leblanc R. M., Zelent B.

Current Topics in Biophysics. Supplement

|

1992

|

tom 16

11

Orientation and spectral properties of two stilbazolium merocyanine dyes in stretched and unstretched polyvinyl alcohol films

71%

Dudkowiak A., Frackowiak D., Teslak E., Gryczynski Z., Gryczynski I.

Acta Biochimica Polonica

|

2007

|

tom 54

|

nr 3

Spectral properties (anisotropy coefficients calculated for absorption, emission and fluorescence decay time) of two stilbazolium merocyanine dyes have been determined to evaluate the applicability of these dyes as sensitizers in photodynamic therapy. The dyes were embedded in an anisotropic polymer matrix. Analysis of the emission decay components measured in polarized light provides information on the interactions of the dye molecules with the polymer matrix being a model of an anisotropic biological system. Different values of the emission anisotropies obtained from various polarized components of fluorescence decays have shown that the orientations of the dye molecules influence their interactions with the polymer. This means that differently oriented dye molecules located in biological systems should exhibit different interactions with membranes. The chain length and type of side groups attached as well as the salt form of the dye molecule were shown to influence the dye-polymer interactions and should be taken into account before the application of merocyanine dyes in medicine. These dyes seem to be promising optical sensors with spectral properties, including the calculated anisotropy coefficients, sensitive to the molecular environment, useful to study orientation and interaction with neighbouring molecules in biological membranes.

12

Preliminary studies of phthalocyanine sensitizers incorporated into human leukemia cells from two cell-lines

71%

Wiktorowicz K., Cofta J., Dudkowiak A., Waszkowiak A., Frackowiak D.

Acta Biochimica Polonica

|

2004

|

tom 51

|

nr 3

Three phthalocyanine dyes-sensitizers were incorporated into two types of human T leukemia cells from two cell-lines: CCRF and MOLT 4. The efficiency of the dye incorporation into cells and photochemical properties of stained cells were investigated using fluorescence spectroscopy. The dyes exhibited different properties in each of the two cell-lines. Small differences in cell membrane properties have a strong influence on the efficiency of dye incorporation and on the course of photodynamic reaction. It is suggested that, for a given patient, an optimal dye-sensitizer should be established before photodynamic treatment.

13

Incorporation of stilbazolium merocyanines into resting and stimulated mononuclear leukocytes

71%

Frackowiak D., Wiktorowicz K., Cofta J., Niedbalska M., Latosinska M.

Acta Biochimica Polonica

|

1995

|

tom 42

|

nr 1

Stimulated and resting mononuclear leukocytes were incubated with a stilbazolium merocyanine dye l-(6'-hydroxyhexyl)-4-[(4-oxocyclohexa-2,5-dienylidene)ethylide- ne]-l,4-dihydropyridine and immobilized in isotropic and stretched polyvinyl alcohol film. Polarized absorption, fluorescence and fluorescence excitation spectra were collected and the anisotropy of absorption and emission were calculated. Analysis of the spectra pointed to: i. the occurrence of perturbation of the membrane structure by incubation with the dye, and ii. influence of the blood serum addition, during the process of incubation with.the dye, on the efficiency of incorporation of merocyanine into the cells and the degree of the dye orientation in the membrane. A small fraction of the dye molecules introduced into resting cells was found oriented to a higher degree than a large fraction incorporated into stimulated cells. The incubation time longer than 15 min caused strong changes in the membrane structure both of the resting and stimulated cells.

14

Zdrowe niezdrowe slonce

70%

Frackowiak D., Dudkowiak A., Ptak A.

Wiedza i Życie

|

2003

|

nr 08

30-33

15

The interactions of phthalocyanines with stimulated and resting human peripheral blood mononuclear cells

61%

Frackowiak D., Waszkowiak A., Manikowski H., Ion R. M., Cofta J., Wiktorowicz K.

Acta Biochimica Polonica

|

2001

|

tom 48

|

nr 1

The interactions of two metal-free phthalocyanines [(H2Pc) and Solar Pc (with four peripherical groups: SO2N(CH2CH2OH)2)] and of one metal substituted dye (CoPc) with resting and stimulated human peripheral blood mononuclear cells (PBMC) were compared. The absorption, fluorescence, photoacoustic and EPR spectra of both resting cells and cells stimulated by phytohaemagglutinin, incubated in dimethyl sulfoxide (DMSO) with very low or 95% water content and with or without dye addition, were measured. The fate of the light absorbed by the samples was investigated. It is known that singlet oxygen production is crucial for photodynamic action of dyes. Thermal deactivation and luminescence emission compete with this process, so investigation of these alternative paths of sensitizer deactivation provides information about photodynamic action. The incorporation of the investigated dyes into cells and the perturbation of the cell structure caused by the dyes, the incubation solvent and the activator were investigated by comparing the spectral properties of PBMC before and after stimulation and incubation. Incubation of the cells for 1 h in a solution of Solar Pc in 99.5% aqueous DMSO, resulted in an efficient dye incorporation which was highly selective. Solar Pc being introduced much more efficiently into stimulated cells than into resting cells.

16

Pesticide residues in crops produced in north-western Poland

51%

Nowacka A., Gnusowski B., Walorczyk S., Drozdzynski D., Raczkowski M., Holodynska A., Frackowiak D., Swoboda W.

Progress in Plant Protection

|

2012

|

tom 52

|

nr 4

In 2011, 262 crop samples, originating from farms located in five voivodeships of north‐western Poland, were tested for the presence of pesticide residues. Studies were conducting in framework of official control and included 23 products and 230 compounds. Several multi‐residue methods based on gas chromatography and high performance liquid chromatography (GC‐ECD/NPD, GC‐MS/MS, HPLC‐UV/PDA, LC‐MS/MS) and one single‐residue method based on spectrophotometric analysis were used for determination of pesticide residues. Totally, 26 compounds were detected in 29.0% of analysed samples. Exceedances of maximum residue levels (MRLs) were found in 0.4% of analysed samples, while the use of unapproved plant protection products in 4.2% of the samples. Pesticide residues were found mostly in samples of apples (84.6%), carrots (56.0%) and potatoes (50.0%). The frequency of their occurrence in the samples taken from individual voivodeships has differed from the average for the entire study area and ranged from 15.9–39.6%, and was the highest in food products from Kujawsko‐pomorskie Voivodeship, while the lowest from Wielkopolskie Voivodeship.

17

Zastosowanie fluorescencji w badaniach przyrodniczych i w medycynie

50%

Frackowiak D.

Wszechświat

|

1952

|

nr 01-02

18

Pesticide residues in agricultural crops (2012)

42%

Nowacka A., Gnusowski B., Walorczyk S., Drozdzynski D., Raczkowski M., Horodynska-Kulas A., Frackowiak D., Wojcik A., Ziolkowski A., Przewozniak M., Swoboda W.

Progress in Plant Protection

|

2014

|

tom 54

|

nr 2

In 2012, the Institute of Plant Protection – National Research Institute within the official control of pesticide residues tested samples of agricultural products originating from a primary production. The samples were taken randomly from domestic farms by inspectors of the Plant Health and Seed Inspection. The study comprised 236 compounds and 52 products. 1,302 samples were analysed, including 622 vegetable samples, 302 fruit samples, 356 cereal samples and 22 other product samples. Pesticide residues of 43 compounds were detected in 221 samples of 29 products. Residues of two or more pesticides were found in 4.6% of analysed samples. Pesticide residues were found in 30.1% of fruit samples, 17.5% of vegetable samples and 5.9% of cereal samples. Their presence was often observed in celeriac (57.1%), carrots (54.5%), gooseberries (50.0%), tomatoes (46.8%), sweet peppers (38.5%), apples (38.5%), strawberries (37.8%) and parsley roots (35.1%). Chlorpyrifos residues in carrots and Chinese cabbage, dithiocarbamates in pears, potatoes, currants, apples, strawberries, lettuce and tomatoes, chlorothalonil in tomatoes, captan in pears, boscalid in strawberries, linuron in parsley roots, azoxystrobin in tomatoes, cyprodinil and fludioxonil in strawberries were detected most frequently. The exceedances of the Maximum Residue Levels (MRLs) were found in 0.4% of the samples, while unauthorized substances in 2.2% of analysed samples.

19

Pesticide residues in Polish crops (2011)

32%

Nowacka A., Gnusowski B., Walorczyk S., Drozdzynski D., Raczkowski M., Holodynska A., Frackowiak D., Wojcik A., Ziolkowski A., Przewozniak M., Swoboda W., Rzeszutko U., Domanska I., Jurys J., Lozowicka B., Kaczynski P., Rutkowska E., Jankowska M., Hrynko I., Szpyrka E., Rupar J., Rogozinska K., Kurdziel A., Slowik-Borowiec M., Szala J., Szponik M., Michel M.

Progress in Plant Protection

|

2012

|

tom 52

|

nr 4

In 2011, a total of 977 samples of domestic crops were tested in the official control of pesticide residues carried out by the Institute of Plant Protection – National Research Institute. The samples were taken randomly by the staff of Plant Health and Seed Inspection at production sites in the whole country. The monitoring programme covered 230 compounds and 38 products. 126 samples of fruit, 484 samples of vegetables, 346 samples of cereals and 21 samples belonging to other products groups were analysed. Residues of 43 compounds were detected in 21.7% of the samples. Violations of MRLs were found in 0.6% of analysed samples, while the unauthorised plant protection product use in 2.5% of samples tested. Pesticide residues were detected in 58.7% of fruit samples, 23.8% of vegetable samples and 4.9% of cereal samples and in 28.6% of other samples. They were found most often in samples of apples (60.5%), tomatoes (52.6%), sweet peppers (50.0%) and carrots (42.1%). Most of the residues detected in twenty five commodities were fungicides and insecticides, and their percentages from 335 findings were equal respectively to 63.9% and 32.5%. The most commonly found were residues of chlorothalonil in tomatoes (31.6%), chlorpyrifos in carrots (28.9%), prochloraz in mushrooms (26.1%), and dithiocarbamates in apples (25.4%), potatoes (24.2%) and tomatoes (21.1%).

20

Pozostałości środków ochrony roślin w płodach rolnych (rok 2010)

32%

Nowacka A., Gnusowski B., Walorczyk S., Drozdzynski D., Raczkowski M., Holodynska A., Frackowiak D., Wojcik A., Ziolkowski A., Rzeszutko U., Domanska I., Jurys J., Lozowicka B., Kaczynski P., Rutkowska E., Jankowska M., Hrynko I., Szpyrka E., Rupar J., Rogozinska K., Kurdziel A., Slowik-Borowiec M., Michel M., Kuzmienko A., Szala J.

Progress in Plant Protection

|

2011

|

tom 51

|

nr 4

In total, 1351 samples of fresh fruit, vegetables and agricultural crops of Polish origin were analysed in 2010 in five laboratories of the Institute of Plant Protection – National Research Institute. The monitoring programme covered 52 commodities and 143 pesticides including some isomers and breakdown products. Residues of 48 compounds, mainly fungicides (26), were detected. The percentage of samples with residues at or below the MRL was 24.2%. In 74.8% of the samples no residues were found. Violations of MRLs were stated in 1.0% of the samples, while the use of non-approved pesticides in 2.7% of the samples tested. Pesticide residues were detected most often in samples of fruit (41.7%), especially in samples of gooseberries (70.0%), cherries (61.3%) and apples (52.4%). Samples of vegetables, as well as agricultural crops were less contaminated with pesticide residues. However, a high sample percentage of tomatoes grown under cover (43.1%) or in the field (60.3%) contained pesticide residues.

Ograniczanie wyników

Przekazywanie energii w jednostkach fotosytetycznych

Spectral properties of cyanobacteria adapted to green and red light

Opóźniona luminescencja fikobilistów

Wpływ matrycy ciekłokrystalicznej na polaryzację widm bakteriochlorofilu a i chlorofilu c

The comparison of excitation energy transfer processes in phycobilisomes from Anabaena variabilis and Anabaena azollae

Incorporation of stilbazolium merocyanines into human leukocytes measured by flow cytometry

Effect of chromatic adaptation of spectral properties and orientation of complexes and on energy transfer in cyanobacteria Tolypothrix cells embedded in skew stretched poly[vinyl alcohol] films

The incorporation of various porphyrins into blood cells measured via flow cytometry, absorption and emission spectroscopy

Spectral properties of phthalocyanines incorporated into resting and stimulated human peripheral blood cells

Agregacja chlorofilu w układach modelowych

Orientation and spectral properties of two stilbazolium merocyanine dyes in stretched and unstretched polyvinyl alcohol films

Preliminary studies of phthalocyanine sensitizers incorporated into human leukemia cells from two cell-lines

Incorporation of stilbazolium merocyanines into resting and stimulated mononuclear leukocytes

Zdrowe niezdrowe slonce

The interactions of phthalocyanines with stimulated and resting human peripheral blood mononuclear cells

Pesticide residues in crops produced in north-western Poland

Zastosowanie fluorescencji w badaniach przyrodniczych i w medycynie

Pesticide residues in agricultural crops (2012)

Pesticide residues in Polish crops (2011)

Pozostałości środków ochrony roślin w płodach rolnych (rok 2010)