Regulated cell death (RCD) encompasses the activation of cellular pathways that initiate and execute a self-dismissal process. RCD occur over a range of stressors doses that overcome pro-survival cellular pathways, while higher doses cause excessive damage leading to passive accidental cell death (ACD). Hydrogen peroxide (HP) has been proposed as a potential tool to control harmful cyanobacterial blooms, given its capacity to remove cyanobacterial cells and oxidize cyanotoxins. HP is a source of hydroxyl radicals and is expected to induce RCD only within a limited range of concentrations. This property makes this compound very useful to better understand stress-driven RCD. In this work, we analyzed cell death in microcystin-producing by means of a stochastic dose response model using a wide range of HP concentrations (0, 0.29, 1.76, 3.67, 7.35, 14.70, and 29.5 mM). We used flow cytometry and unsupervised classification to study cell viability and characterize transitional cell death phenotypes after exposing cells to HP for 48 and 72 h. Non-linear regression was used to fit experimental data to a logistic cumulative distribution function (cdf) and calculate the half maximal effective concentration (EC). The EC of exposed to HP were 3.77 ± 0.26 mM and 4.26 ± 0.22 mM at 48 and 72 h, respectively. The derivative of cdf (probability density function; pdf) provided theoretical and practical demonstration that EC is the minimal dose required to cause RCD in 50% of cells, therefore maximizing the probability of RCD occurrence. 1.76 mM HP lead to an antioxidant stress response characterized by increased reactive oxygen species (ROS) levels and HP decomposition activity. The exposure of 3.67 mM HP induced a dose-related transition in cell death phenotype, and produced several morphological changes (a less dense stroma, distortion of the cell membrane, partial disintegration of thylakoids, extensive cytoplasmic vacuolation and highly condensed chromatin). The EC and the stochastic cdf and pdf together with the multidimensional transitional phenotypic analysis of single cells contribute to further characterize cell death pathways in cyanobacteria.
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http://dx.doi.org/10.3389/fmicb.2021.636157 | DOI Listing |
JAMA Netw Open
January 2025
Davidoff Cancer Center, Rabin Medical Center, Petach Tikvah, Israel.
Importance: Three similar phase 3 randomized clinical trials have investigated PD-1/PD-L1 (programmed cell death 1 protein/programmed cell death 1 ligand 1) inhibitors in combination with platinum-based chemotherapy vs chemotherapy alone as first-line treatment for advanced urothelial carcinoma (IMvigor130, atezolizumab; KEYNOTE-361, pembrolizumab; and CheckMate901, nivolumab). Only CheckMate901 reported overall survival (OS) benefit for the combination. The reason for these inconsistent results is unclear.
View Article and Find Full Text PDFImmunomodulatory drug (IMiD) resistance is a key clinical challenge in myeloma treatment. Previous data suggests almost one third of myeloma patients acquire mutations in the key IMiD effector cereblon by the time they are pomalidomide refractory. Some events, including stop codons/frameshift mutations and copy loss, having clearly explicable effects on cereblon function.
View Article and Find Full Text PDFJAMA Cardiol
January 2025
National Amyloidosis Centre, Division of Medicine, University College London, Royal Free Hospital, London, United Kingdom.
Importance: Patients with transthyretin (ATTR) cardiac amyloid infiltration are increasingly diagnosed at earlier disease stages with no heart failure (HF) symptoms and a wide range of cardiac amyloid infiltration.
Objective: To characterize the clinical phenotype and natural history of asymptomatic patients with ATTR cardiac amyloid infiltration.
Design, Setting, And Participants: This cohort study analyzed data of all patients at 12 international centers for amyloidosis from January 1, 2008, through December 31, 2023.
Mol Biol Rep
January 2025
College of Life Sciences, Liaoning Normal University, Dalian, Liaoning, 116029, China.
Background: High temperature is a critical environmental factor leading to mass mortality in oyster aquaculture in China. Recent advancements highlight the physiological regulation function of γ-aminobutyric acid (GABA) in the adaptation of environmental stress.
Methods And Results: This study examined the physiological responses of the Pacific oyster (Crassostrea gigas) upon high temperature exposure, focusing on the histopathological changes in gill, the GABA concentration, the mRNA expression and activities of apoptosis-related genes.
J Mol Histol
January 2025
Obstetrics and Gynecology, The Affiliated People's Hospital of Ningbo University, 251 East Baizhang Road, Ningbo, 315040, Zhejiang, China.
Long non-coding RNAs (lncRNAs) have emerged as pivotal regulatory molecules in cancer biology. Among these, long intergenic non-protein coding RNA 02418 (LINC02418), a recently identified lncRNA, has been linked to endometrial cancer (EC), although its function and operational mechanisms are largely unclear. The present investigation aims to elucidate the molecular mechanism through which LINC02418 influences EC pathogenesis.
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