http://hdl.handle.net/11320/50 Mon, 01 Jun 2026 16:17:51 GMT 2026-06-01T16:17:51Z http://hdl.handle.net/11320/18166 Tytuł: New Steroidal Selenides as Proapoptotic Factors Autorzy: Jastrzębska, Izabella; Wawrusiewicz-Kurylonek, Natalia; Grześ, Paweł A.; Ratkiewicz, Artur; Grabowska, Ewa; Czerniecka, Magdalena; Czyżewska, Urszula; Tylicki, Adam Abstrakt: Cytostatic and pro-apoptotic effects of selenium steroid derivatives against HeLa cells were determined. The highest cytostatic activity was shown by derivative 4 (GI₅₀25.0 µM, almost complete growth inhibition after three days of culture, and over 97% of apoptotic and dead cells at 200 µM). The results of our study (cell number measurements, apoptosis profile, relative expression of apoptosis related APAF1, BID, and mevalonate pathway-involved HMGCR, SQLE, CYP51A1, and PDHB genes, and computational chemistry data) support the hypothesis that tested selenosteroids induce the extrinsic pathway of apoptosis by affecting the cell membrane as cholesterol antimetabolites. An additional mechanism of action is possible through a direct action of derivative 4 to inhibit PDHB expression in a way similar to steroid hormones. Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/11320/18166 2023-01-01T00:00:00Z http://hdl.handle.net/11320/17771 Tytuł: Ecological status of shallow Lake Gorbacz (NE Poland) in its final stage before drying up Autorzy: Zieliński, Piotr; Ejsmont-Karabin, Jolanta; Grabowska, Magdalena; Karpowicz, Maciej Abstrakt: The article assesses the ecological status of shallow Gorbacz Lake (NE Poland) in the last stage before complete drying up. For last few years hydrological regime of the lake catchment has been changed dramatically which was caused by functioning nearby peat mine and longer autumn drought periods for following years. Progressing macrophytes succession leaded complete emergent macrophytes overgrowth of the lake beginning from 2000. The analyses include records of previous samples and data for morphology, water quality, phytoplankton, zooplankton and macrophytes. The trophic status of Gorbacz Lake was verified compare to the previous studies. The results indicate that even with minimum amount of water Gorbacz Lake itself still keeps its dystrophic character with increasing of water color and of DOC, biogenic substances, chlorophyll a concentrations. Humic State Index (HSI) and hydrochemical dystrophy index (HDI) confirm the dystrophic status of the lake with values 71.3 and 76.2 respectively. Both typical phytoplankton representatives of eutrophic and dystrophic waters were recorded. Very high diversity of desmids in the telmatoplankton, indicates the observed process of shallowing in the reservoir. Planktonic crustacean fauna was represented by small filtrators. Rotifera community was strongly dominated by Trichocerca simonei. The article concludes with the main causes of the observed changes and some future remarks for the lake state. Sat, 01 Jan 2011 00:00:00 GMT http://hdl.handle.net/11320/17771 2011-01-01T00:00:00Z http://hdl.handle.net/11320/17765 Tytuł: Impact of Sclerotinia sclerotiorum Infection on Lettuce (Lactuca sativa L.) Survival and Phenolics Content—A Case Study in a Horticulture Farm in Poland Autorzy: Macioszek, Violetta Katarzyna; Marciniak, Paulina; Kononowicz, Andrzej Kiejstut Abstrakt: Sclerotinia sclerotiorum is a cause of a prevalent and destructive disease that attacks many horticultural food crops, such as lettuce. This soil-borne necrotrophic fungal pathogen causes significant economic losses in worldwide lettuce production annually. Furthermore, current methods utilized for management and combatting the disease, such as biocontrol, are insufficient. In this study, three cultivars of lettuce (one Crispy and two Leafy cultivars of red and green lettuce) were grown in central Poland (Lodz Voivodeship), a widely known Polish horticultural region. In the summer and early autumn, lettuce cultivars were grown in control and S. sclerotiorum-infected fields. The lettuce cultivars (Templin, Lollo Rossa, and Lollo Bionda) differed phenotypically and in terms of the survival of the fungal infection. The Crispy iceberg Templin was the most susceptible to S. sclerotiorum infection compared to the other cultivars during both vegetation seasons. The total content of phenolic compounds, flavonoids, and anthocyanins varied among cultivars and fluctuated during infection. Moreover, phenolic content was affected by vegetation season with alterable environmental factors such as air temperature, humidity, soil temperature, and pH. The most increased levels of phenolics, both flavonoids and anthocyanins in infected plants, were observed in the Leafy red Lollo Rossa cultivar in both crops. However, the highest survival/resistance to the fungus was noticed for Lollo Rossa in the summer crop and Lollo Bionda in the autumn crop. Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/11320/17765 2023-01-01T00:00:00Z http://hdl.handle.net/11320/17764 Tytuł: Jasmonic Acid as a Mediator in Plant Response to Necrotrophic Fungi Autorzy: Macioszek, Violetta Katarzyna; Jęcz, Tomasz; Ciereszko, Iwona; Kononowicz, Andrzej Kiejstut Abstrakt: Jasmonic acid (JA) and its derivatives, all named jasmonates, are the simplest phytohormones which regulate multifarious plant physiological processes including development, growth and defense responses to various abiotic and biotic stress factors. Moreover, jasmonate plays an important mediator’s role during plant interactions with necrotrophic oomycetes and fungi. Over the last 20 years of research on physiology and genetics of plant JA-dependent responses to pathogens and herbivorous insects, beginning from the discovery of the JA co-receptor CORONATINE INSENSITIVE1 (COI1), research has speeded up in gathering new knowledge on the complexity of plant innate immunity signaling. It has been observed that biosynthesis and accumulation of jasmonates are induced specifically in plants resistant to necrotrophic fungi (and also hemibiotrophs) such as mostly investigated model ones, i.e., Botrytis cinerea, Alternaria brassicicola or Sclerotinia sclerotiorum. However, it has to be emphasized that the activation of JA-dependent responses takes place also during susceptible interactions of plants with necrotrophic fungi. Nevertheless, many steps of JA function and signaling in plant resistance and susceptibility to necrotrophs still remain obscure. The purpose of this review is to highlight and summarize the main findings on selected steps of JA biosynthesis, perception and regulation in the context of plant defense responses to necrotrophic fungal pathogens. Fri, 27 Jan 2023 00:00:00 GMT http://hdl.handle.net/11320/17764 2023-01-27T00:00:00Z