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Immunofluorescent localization of ubiquitin and proteasomes in nucleolar vacuoles of soybean root meristematic cells
D. St？piński
European Journal of Histochemistry , 2012, DOI: 10.4081/ejh.2012.13
Abstract: In this study, using the immunofluorescent method, the immunopositive signals to ubiquitin and proteasomes in nucleoli of root meristematic cells of soybean seedlings have been observed. In fact, those signals were present exclusively in nucleolar vacuoles. No signals were observed in the nucleolar territory out of the nucleolar vacuoles or in the nucleoli without vacuoles. The ubiquitin-proteasome system (UPS) may act within the nucleoli of plants with high metabolic activities and may provide an additional level of regulation of intracellular proteolysis via compartment-specific activities of their components. It is suggested that the presence of the UPS solely in vacuolated nucleoli serves as a mechanism that enhances the speed of ribosome subunit production in very actively transcribing nucleoli. On the other hand, nucleolar vacuoles in a cell/nucleus could play additional roles associated with temporary sequestration or storage of some cellular factors, including components of the ubiquitin-proteasome system.
Effect of short- and long-lasting chilling on pre-rRNA synthesis and transport in root meristematic cells of three soybean cultivars
Dariusz St？piński
Acta Societatis Botanicorum Poloniae , 2003, DOI: 10.5586/asbp.2003.041
Abstract: Autoradiographic studies of 3H-uridine incorporation (20-min incubation) and dynamics of radioactive particle translocation from nucleolus into cytoplasm (following 80-min postincubation in non-radioactive medium) in root meristematic cells of soybean have been carried out. The experiment was performed with plants subjected to 4-day acclimation in chilling or subjected to 2-hour cold stress and control plants. Three cultivars of soybean: Mazowia, Polan and Progres (cultivated in Poland) were used in the experiment. It has been shown that in control conditions the greatest number of RNA precursor is incorporated into nucleoli after 20-min incubation. Following 80-min postincubation cytoplasm is the most radioactive area of the cell - this mainly testifies to dynamic translocation of radioactive ribosome subunits from nucleolus into cytoplasm. In chilling conditions the reduction of 3H-uridine incorporation into cells occurs, as compared to control conditions. Plants subjected to a 4-day acclimation incorporate the radioactive precursor more intensively than plants subjected to cold stress. Following 80-min postincubation - in the case of acclimated plants - the nucleolus is the most radioactive area of the cell, which testifies to accumulation of pre-rRNA in it. After the cold stress cytoplasm is more radioactive than the nucleolus. In all three cultivars the processes of synthesis and transport of pre-rRNA particles are similar, only their intensity is different. Morphometric measurements of nucleoli in all cultivars subjected to 4-day chilling have shown that root cell nucleoli are larger than those in control. This phenomenon can be connected with stronger inhibition of rRNA transport than its synthesis.
GA3 content in young and mature antheridia of Chara tomentosa estimated by capillary electrophoresis
Andrzej Ka？mierczak,Dariusz St？piński
Folia Histochemica et Cytobiologica , 2011, DOI: 10.5603/4631
Abstract: The content of gibberellic acid (GA3) in male sex organs of Chara tomentosa L. was estimated using capillary electrophoresis. Young antheridia contained 0.25 μg GA3 while mature ones 0.48 μg per antheridium. Although there are significant differences in GA3 content in antheridia between C. vulgaris and C. tomentosa, these values calculated per one spermatid are 2.4 and 3.3 pg, respectively. The present results compiled with the previous knowledge about regulation of GA3-dependent development of Characeae species allow an implication that the mechanisms controlling antheridia differentiation in both species can be similar
Szczerbiec (the jagged sword) – the coronation sword of the kings of Poland
Biborski, Marcin,St？piński, Janusz,？abiński, Grzegorz
Gladius , 2011, DOI: 10.3989/gladius.2011.0006
Abstract: The paper presents the results of newest research on the Szczerbiec – the Polish coronation sword. Technological examinations revealed that the blade was manufactured of bloomery steel, with C contents of c. 0.3-0.6 %. The blade was thermally treated (quenched and tempered) in its part below the hilt. The X-ray revealed no pattern welding or composite structures. All this testifies to the authenticity of the sword as a genuine medieval weapon and not (as sometimes suggested in scholarship) a 19th c. replica. The pommel and the crosspiece were made of silver and then coveted with nielloed gold plates. A combination of typological, stylistic and epigraphic data suggests a date of c. 1250 for the sword. As suggested by the lavishness of ornament and inscriptions of the all-metal hilt, as well as by the rectangular cross-section of the grip, the Szczerbiec may have been influenced by swords of the Mediterranean (especially Iberian) cultural sphere. The swords of Sancho IV of Castille and Léon, of Santa Casilda, of Friedrich II von Hohenstaufen, of the Comtés de Dreux and a sword from the Museo Arqueológico Nacional in Madrid seem to be especially relevant analogies. Of particular significance is a Hebrew or Hebrew-Latin inscription on the crosspiece, which fits into a tradition of Hebrew-inspired voces magicae. The first owner of the sword was in all probability Boles?aw Pobo?ny (the Pious), Duke of Great Poland (died 1279). For Duke Boles?aw the sword was his gladius iustitiae and a protective talisman. The weapon was then inherited (probably through marriage to his daughter Jadwiga c. 1293) by Duke Boles aw Pobo ny (the Short or the Ell-high) (the future King of Poland). It was in all probability Duke Vladislao okietek who first used the sword as a coronation insignia. Este trabajo presenta los últimos resultados de la investigación sobre la Szczerbiec – la espada de coronación polaca. El examen tecnológico revela que la espada se fabricó a partir de hierro forjado acerado con un contenido de carbono del 0.3-0.6%. La espada recibió tratamiento térmico (templado y revenido) en la hoja por debajo del pu o. El examen radiográfico no revela pattern welding o una estructura compuesta. Todo ello demuestra la autenticidad de la espada como una genuina arma medieval y no como una réplica del s. XIX (según se ha propuesto en ocasiones). El pomo y la guarda son de plata cubierta con placas de oro nielado. La combinación de análisis tipológico, estilístico y epigráfico sugiere una fecha de c. 1250 d.C. para la espada. La rica decoración y las inscripciones del pu o
A renaissance sword from Racibórz
Biborski, Marcin,St？piński, Janusz,Zabiński, Grzegorz
Gladius , 2004, DOI: 10.3989/gladius.2004.41
Abstract: A broken sword was found in Racibórz, in an assumed Ducal grave, dated back to the 1520s. The sword blade can be classified as a variation of the Type XVII (similar to the Type XVIIIb), the pommel belongs to the Type T5 and the crosspiece to the Type 12. As blade types XVII were mainly in use ca. 1350-1450, it cannot be excluded that the blade of the Racibórz sword was re-hilted and provided with a more fashionable pommel and a crosspiece ca. 1500. Several analogous examples of swords are presented in the paper. Concerning archaeometallurgical analysis of the blade, it was made of one piece of iron, carburised and then hardened. In result, a highquality blade with a soft core and hard edges was produced. For the sake of comparison, selected examples of archaeometallurgical analysis of other late medieval blades are provided. El objeto de este trabajo es una espada fragmentada encontrada en Racibórz (Polonia), presumiblemente en un enterramiento ducal, datada con anteriodidad a 1520. Según la tipología de Oakeshott, la hoja puede ser clasificada como una variante del tipo XVII (similar al Tipo XVIIIb), el pomo pertenece al Tipo T5 y el arriaz al Tipo 12. Dado que las hojas del Tipo XVII fueron fundamentalmente usadas c. 1350-1450, no se puede excluir que la hoja de la espada Racibórz fuera guarnecida de nuevo con un pomo y un arriaz a la moda de c. 1500. En este trabajo se presentan otras espadas análogas. En cuanto al análisis aqueometalúrgico de la hoja, puede decirse que estaba hecha de una sola pieza de hierro, carburizado y endurecido. El resultado es una hoja de alta calidad, con un núcleo dúctil y fuertes filos. Como elementos de comparación se proporcionan paralelos escogidos de análisis arqueometalúrgicos sobre otras hojas bajomedievales.
Czynniki prognostyczne choroby trzewnej u dzieci z cukrzyca typu 1
Ma？gorzata My？liwiec,Anna Balcerska,Jan St？piński,Alicja B？kowska
Pediatric Endocrinology, Diabetes and Metabolism , 2006,
Abstract: Wprowadzenie: Przedmiotem dyskusji jest cz sto wspó istnienia celiakii i cukrzycy typu 1 oraz standaryzacja metod diagnostycznych w kierunku rozpoznania celiakii u dzieci z cukrzyc typu 1. Cel pracy: Celem pracy by a ocena cz sto ci choroby trzewnej u dzieci z cukrzyc typu 1 (DM1) w regionie pomorskim, a tak e poszukiwanie czynników prognostycznych rozwoju celiakii u dzieci z DM1. Materia i metody: Badania przeprowadzono w grupie 70 dzieci z nowo rozpoznan DM1 w wieku 9,47±4,59 roku (grupa 1) oraz w ród 223 dzieci z d ugotrwa DM1 (grupa 2; redni wiek 10,20±3,87 roku, redni czas trwania choroby 4,47±3,16 roku). U wszystkich badanych pacjentów oznaczono poziom C-peptydu, HbA1c, CRP, TSH, fT4, fT3, wielko wydalania albumin w moczu, poziom przeciwcia przeciwgliadynowych (AGA), przeciwcia przeciw transglutaminazie tkankowej (TGA) metod ELISA, przeciwcia przeciw endomysium mi ni g adkich (EmA) metod immunofluorecencyjn w klasie IgA i IgG, poziom IgA oraz poziom przeciwcia przeciw tyreoglobulinie (TG) i przeciw peroksydazie tarczycowej (TPO) metod ELISA. U wszystkich badanych dzieci wykonano USG tarczycy, a u dzieci z podwy szonym mianem przeciwcia TGA, AGA lub Ema wykonano tak e biopsj jelita cienkiego. Wyniki: Potwierdzon w biopsji chorob trzewn stwierdzono w grupie 1 u 5,7% pacjentów, a w grupie 2 - u 9,4% dzieci. Cz sto wyst powania przeciwcia TGA w ród pacjentów z grupy 2 wynosi a 9,52%, AGA - 7,62%, EmA - 6,19%. W grupie 1 u 10%, a w grupie 2 - 24,2% pacjentów stwierdzono autoimmunologiczne zapalenie tarczycy. Dzieci z d ugotrwa DM1 z rozpoznan celiaki (grupa A) charakteryzowa y si statystycznie znamiennym ni szym wiekiem zachorowania na DM 1 (0,003), wy szym poziomem HbA1c (p=<0,001), CRP (p<0,001), wy szym poziomem wydalania albumin w moczu w porównaniu do grupy dzieci bez celiakii (grupa B). Najwy sz czu o (95,2%) w diagnostyce celiakii u dzieci z cukrzyc typu 1 wykaza test serologiczny z oznaczeniem przeciwcia TGA, najni sz (61,9%) - test z oznaczeniem przeciwcia EmA. Wnioski: Chorobowo w przypadku potwierdzonej biopsj choroby trzewnej u dzieci z DM 1 jest wysoka (9,4%). Oznaczenie przeciwcia przeciw transglutaminazie tkankowej jest najczulszym parametrem przesiewowym w kierunku rozpoznania celiakii u dzieci z DM 1.
'Elaioplasts' identified as lipotubuloids in Althaea rosea, Funkia sieboldiana and Vanilla planifolia contain lipid bodies connected with microtubules
Maria Kwiatkowska,Dariusz St？piński,Katarzyna Pop？ońska,Agnieszka Wojtczak
Acta Societatis Botanicorum Poloniae , 2011, DOI: 10.5586/asbp.2011.036
Abstract: "Elaioplasts" observed in Vanilla planifolia, Funkia Sieboldiana and Althaea rosea exhibit all the features characteristic of lipotubuloids earlier described in Ornithogalum umbellatum. They are cytoplasmic domains containing aggregates of lipid bodies connected with microtubules. The immunogold technique confirmed the presence of tubulin in this domain. These structures do not have their own membranes but they are surrounded by a tonoplast at the side of a vacuole since they invaginate into it. In cytoplasm of this domain among lipid bodies there are numerous ribosomes, ER cisternae and vesicles as well as few mitochondria, Golgi structures and microbodies while at older developmental stages there are also autolytic vacuoles. The fact that they are so similar to O. umbellatum lipotubuloids suggest that "elaioplasts" of V. planifolia, F. Sieboldiana and A. rosea can also be named lipotubuloids.
DGAT2 revealed by the immunogold technique in Arabidopsis thaliana lipid bodies associated with microtubules DGAT2 revealed by the immunogold technique in Arabidopsis thaliana lipid bodies associated with microtubules
Maria Kwiatkowska,Dariusz St？piński,Katarzyna Pop？ońska,Agnieszka Wojtczak
Folia Histochemica et Cytobiologica , 2012, DOI: 10.5603/19752
Abstract: The immunogold technique with anti-diacylglycerol acyltransferase 2 (DGAT2) antibody revealed in A. thaliana embryo and root meristematic cells gold particles manifesting the presence of DGAT2 in ER as well as in lipid bodies. This being so, lipid synthesis could take place both in ER and in the lipid bodies. The presence of microtubules around the lipid bodies was evidenced under transmission EM. Detection of tubulin around the lipid bodies using the immunogold technique with anti-a-tubulin is in agreement with the above observations. Connection of lipid bodies with microtubules was also detected by us in other plants where they probably participated in lipid synthesis. A similar phenomenon may take place in A. thaliana. The immunogold technique with anti-diacylglycerol acyltransferase 2 (DGAT2) antibody revealed in A. thaliana embryo and root meristematic cells gold particles manifesting the presence of DGAT2 in ER as well as in lipid bodies. This being so, lipid synthesis could take place both in ER and in the lipid bodies. The presence of microtubules around the lipid bodies was evidenced under transmission EM. Detection of tubulin around the lipid bodies using the immunogold technique with anti-a-tubulin is in agreement with the above observations. Connection of lipid bodies with microtubules was also detected by us in other plants where they probably participated in lipid synthesis. A similar phenomenon may take place in A. thaliana.
Microtubule heterogeneity of Ornithogalum umbellatum ovary epidermal cells: non-stable cortical microtubules and stable lipotubuloid microtubules
Maria Kwiatkowska,Dariusz St？piński,Justyna T. Polit,Katarzyna Pop？ońska
Folia Histochemica et Cytobiologica , 2011, DOI: 10.5603/4126
Abstract: Lipotubuloids, structures containing lipid bodies and microtubules, are described in ovary epidermal cells of Ornithogalum umbellatum. Microtubules of lipotubuloids can be fixed in electron microscope fixative containing only buffered OsO4 or in glutaraldehyde with OsO4 post-fixation, or in a mixture of OsO4 and glutaraldehyde [1]. None of these substances fixes cortical microtubules of ovary epidermis of this plant which is characterized by dynamic longitudinal growth. However, cortical microtubules can be fixed with cold methanol according immunocytological methods with the use of b-tubulin antibodies and fluorescein. The existence of cortical microtubules has also been evidenced by EM observations solely after the use of taxol, microtubule stabilizer, and fixation in a glutaraldehyde/OsO4 mixture. These microtubules mostly lie transversely, sometimes obliquely, and rarely parallel to the cell axis. Staining, using Ruthenium Red and silver hexamine, has revealed that lipotubuloid microtubules surface is covered with polysaccharides. The presumption has been made that the presence of a polysaccharide layer enhances the stability of lipotubuloid microtubules. (Folia Histochemica et Cytobiologica 2011, Vol. 49, No. 2, 285–290)
Microtubule heterogeneity of Ornithogalum umbellatum ovary epidermal cells: non-stable cortical microtubules and stable lipotubuloid microtubules
Maria Kwiatkowska,Dariusz St？piński,Justyna T. Polit,Katarzyna Pop？ońska
Folia Histochemica et Cytobiologica , 2011,
Abstract: Lipotubuloids, structures containing lipid bodies and microtubules, are described in ovary epidermalcells of Ornithogalum umbellatum. Microtubules of lipotubuloids can be fixed in electron microscope fixativecontaining only buffered OsO4 or in glutaraldehyde with OsO4 post-fixation, or in a mixture of OsO4 and glutaraldehyde[1]. None of these substances fixes cortical microtubules of ovary epidermis of this plant which ischaracterized by dynamic longitudinal growth. However, cortical microtubules can be fixed with cold methanolaccording immunocytological methods with the use of b-tubulin antibodies and fluorescein. The existence ofcortical microtubules has also been evidenced by EM observations solely after the use of taxol, microtubulestabilizer, and fixation in a glutaraldehyde/OsO4 mixture. These microtubules mostly lie transversely, sometimesobliquely, and rarely parallel to the cell axis. Staining, using Ruthenium Red and silver hexamine, has revealedthat lipotubuloid microtubules surface is covered with polysaccharides. The presumption has been made thatthe presence of a polysaccharide layer enhances the stability of lipotubuloid microtubules.
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