Publications by authors named "Olszewski K"

The increasing prevalence of monocultures has reduced floral diversity, diminishing pollen diet variety for bees. This study examines the impact of monofloral pollen diets (hazel, rapeseed, pine, buckwheat, , goldenrod) on the antioxidant enzyme activities in the fat body from tergite 3, tergite 5, sternite, and hemolymph of honey bees. We show that pollen from plants such as rapeseed, , buckwheat, and goldenrod (rich in phenolic compounds and flavonoids) increases the activities of SOD, CAT, GST, and GPx in the fat body and hemolymph compared to the control group.

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Background: Statistics from the Centers for Disease Control indicate that the use of e-cigarettes, vaping, and other electronic nicotine delivery systems (ENDS) are increasing although data on their safety is limited. While most employers ban smoking in the workplace, tobacco-free policies do not always extend specifically to e-cigarette products.

Methods: An IRB approved exploratory, cross-sectional study was conducted to investigate occupational health professionals' (OHPs) knowledge of e-cigarettes, vaping and ENDS and the ability to create change in tobacco-free workplace policies.

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Introduction: The adulteration of wax foundation is, for many reasons, a growing problem of modern beekeeping not only in Europe but also around the world. Wax foundation contaminated with stearin addition leads to a brood die-off, while paraffin addition negatively affects the strength of combs. It is tenable that such adulterated wax foundation reduces bees' immunity.

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Non-small-cell lung cancer (NSCLC) with concurrent mutations in KRAS and the tumour suppressor LKB1 (KL NSCLC) is refractory to most therapies and has one of the worst predicted outcomes. Here we describe a KL-induced metabolic vulnerability associated with serine-glycine-one-carbon (SGOC) metabolism. Using RNA-seq and metabolomics data from human NSCLC, we uncovered that LKB1 loss enhanced SGOC metabolism via serine hydroxymethyltransferase (SHMT).

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The role of the mitochondrial electron transport chain (ETC) in regulating ferroptosis is not fully elucidated. Here, we reveal that pharmacological inhibition of the ETC complex I reduces ubiquinol levels while decreasing ATP levels and activating AMP-activated protein kinase (AMPK), the two effects known for their roles in promoting and suppressing ferroptosis, respectively. Consequently, the impact of complex I inhibitors on ferroptosis induced by glutathione peroxidase 4 (GPX4) inhibition is limited.

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Nucleotides perform important metabolic functions, carrying energy and feeding nucleic acid synthesis. Here, we use isotope tracing-mass spectrometry to quantitate contributions to purine nucleotides from salvage versus de novo synthesis. We further explore the impact of augmenting a key precursor for purine synthesis, one-carbon (1C) units.

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The morphological changes in fat body cells, tergal gland cells, and the surface areas of the cell nuclei were determined in queen bees of the subspecies . This study focused on 1-, 8-, and 20-day-old uninseminated females kept in colonies, analyzing cells from three locations in the abdomen: the sternite, and tergites III and V. The oenocytes in the sternites were large, oval/circular with a centrally located nucleus, while in tergites III and V, they were small and triangular in the 1-day-old queens.

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Ferroptosis has been recognized as a unique cell death modality driven by excessive lipid peroxidation and unbalanced cellular metabolism. In this study, we established a protein interaction landscape for ferroptosis pathways through proteomic analyses, and identified choline/ethanolamine phosphotransferase 1 (CEPT1) as a lysophosphatidylcholine acyltransferase 3 (LPCAT3)-interacting protein that regulates LPCAT3 protein stability. In contrast to its known role in promoting phospholipid synthesis, we showed that CEPT1 suppresses ferroptosis potentially by interacting with phospholipases and breaking down certain pro-ferroptotic polyunsaturated fatty acid (PUFA)-containing phospholipids.

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How cells coordinate cell cycling with cell survival and death remains incompletely understood. Here, we show that cell cycle arrest has a potent suppressive effect on ferroptosis, a form of regulated cell death induced by overwhelming lipid peroxidation at cellular membranes. Mechanistically, cell cycle arrest induces diacylglycerol acyltransferase (DGAT)-dependent lipid droplet formation to sequester excessive polyunsaturated fatty acids (PUFAs) that accumulate in arrested cells in triacylglycerols (TAGs), resulting in ferroptosis suppression.

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Nucleotides perform important metabolic functions, carrying energy and feeding nucleic acid synthesis. Here, we use isotope tracing-mass spectrometry to quantitate the contributions to purine nucleotides of salvage versus synthesis. We further explore the impact of augmenting a key precursor for purine synthesis, one-carbon (1C) units.

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GaN nanowires grown on metal substrates have attracted increasing interest for a wide range of applications. Herein, we report GaN nanowires grown by plasma-assisted molecular beam epitaxy on thin polycrystalline ZrN buffer layers, sputtered onto Si(111) substrates. The nanowire orientation was studied by X-ray diffraction and scanning electron microscopy, and then described within a model as a function of the Ga beam angle, nanowire tilt angle, and substrate rotation.

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The cystine transporter solute carrier family 7 member 11 (SLC7A11; also called xCT) protects cancer cells from oxidative stress and is overexpressed in many cancers. Here we report a surprising finding that, whereas moderate overexpression of SLC7A11 is beneficial for cancer cells treated with HO, a common oxidative stress inducer, its high overexpression dramatically increases HO-induced cell death. Mechanistically, high cystine uptake in cancer cells with high overexpression of SLC7A11 in combination with HO treatment results in toxic buildup of intracellular cystine and other disulfide molecules, NADPH depletion, redox system collapse, and rapid cell death (likely disulfidptosis).

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The aim of the study was to compare the activities of proteases and their inhibitors in the hemolymph of honeybee workers reared in small-cell combs (SMC) and standard-cell combs (STC) in laboratory cage tests. The analyses conducted in laboratory conditions facilitated assessment of the impact of the comb cell width (small vs. standard) along with eliminating the influence of many environmental factors on the results.

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Article Synopsis
  • Honeybee nests made without synthetic wax have more diverse cell sizes compared to those in commercial beekeeping, which can impact bee biology and evolution.
  • This study aimed to compare antioxidant activities in honeybee workers raised in different comb sizes, finding that those in smaller combs had higher antioxidant levels, suggesting they might be more effective foragers.
  • Results indicated that differences in antioxidant activities are mainly due to the workers' activities rather than their age, highlighting the need for long-term studies to minimize environmental variability's effects on honeybee research.
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Mitochondria are critical to the governance of metabolism and bioenergetics in cancer cells. The mitochondria form highly organized networks, in which their outer and inner membrane structures define their bioenergetic capacity. However, in vivo studies delineating the relationship between the structural organization of mitochondrial networks and their bioenergetic activity have been limited.

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SLC7A11-mediated cystine uptake suppresses ferroptosis yet promotes cell death under glucose starvation; the nature of the latter cell death remains unknown. Here we show that aberrant accumulation of intracellular disulfides in SLC7A11 cells under glucose starvation induces a previously uncharacterized form of cell death distinct from apoptosis and ferroptosis. We term this cell death disulfidptosis.

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Mechanisms of defense against ferroptosis (an iron-dependent form of cell death induced by lipid peroxidation) in cellular organelles remain poorly understood, hindering our ability to target ferroptosis in disease treatment. In this study, metabolomic analyses revealed that treatment of cancer cells with glutathione peroxidase 4 (GPX4) inhibitors results in intracellular glycerol-3-phosphate (G3P) depletion. We further showed that supplementation of cancer cells with G3P attenuates ferroptosis induced by GPX4 inhibitors in a G3P dehydrogenase 2 (GPD2)-dependent manner; deletion sensitizes cancer cells to GPX4 inhibition-induced mitochondrial lipid peroxidation and ferroptosis, and combined deletion of and synergistically suppresses tumor growth by inducing ferroptosis in vivo.

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Social insect societies are characterized by a high level of organization. This is made possible through a remarkably complex array of pheromonal signals produced by all members of the colony. The queen's pheromones signal the presence of a fertile female and induce daughter workers to remain sterile.

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Article Synopsis
  • The study examines the role of proteolytic and antioxidant systems in the immune response of bees, focusing on how these components show immune status and maintain homeostasis.
  • Researchers measured various enzyme activities (proteases, SOD, CAT, AST, ALT, ALP) in the fat body and hemolymph of different bee types: reproductive queens, rebels, and non-reproductive workers.
  • Results indicated that normal workers had higher enzyme activity in both the fat body and hemolymph compared to queens and rebels, with the fat body location influencing these activity levels, enhancing our understanding of stress ecology and labor division in social insects.
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Targeting ferroptosis, a unique cell death modality triggered by unrestricted lipid peroxidation, in cancer therapy is hindered by our incomplete understanding of ferroptosis mechanisms under specific cancer genetic contexts. KEAP1 (kelch-like ECH associated protein 1) is frequently mutated or inactivated in lung cancers, and KEAP1 mutant lung cancers are refractory to most therapies, including radiotherapy. In this study, we identify ferroptosis suppressor protein 1 (FSP1, also known as AIFM2) as a transcriptional target of nuclear factor erythroid 2-related factor 2 (NRF2) and reveal that the ubiquinone (CoQ)-FSP1 axis mediates ferroptosis- and radiation- resistance in KEAP1 deficient lung cancer cells.

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Article Synopsis
  • - This study investigates how the size of bee comb cells (small vs. standard) affects the protein levels and activity of proteases in worker bees' hemolymph, revealing significant differences based on the comb type.
  • - One-day-old workers from small-cell combs have higher protein concentrations, while older workers show the opposite trend, indicating that comb cell width influences bee development and function.
  • - The study suggests differences in roles for bees reared in small versus standard combs, with small-cell bees possibly serving as foragers outside the nest, and emphasizes the need for long-term research to confirm these findings.
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