Cell Collapse Research Articles

In-plane compression of 3D-printed self-similar hierarchical honeycombs – Static and dynamic analysis

In-plane collapse behaviors of second-order wood-inspired hierarchical honeycombs (replace each solid side of a conventional honeycomb with a wall comprising smaller hexagons) under quasi-static and dynamic in-plane compression were examined via experiments and finite element (FE) simulation. Analytical formula for the initial crushing strength and plateau crushing force were also developed. Compared to the conventional honeycomb, a hierarchical honeycomb displays a higher mean post-yield crushing stress, although its specific energy absorption is slightly lower. Their initial phase of energy dissipation is linked to the rotation and shortening/compression of the inclined hierarchical walls. Due to less catastrophic collapse of the smaller first-order cells, the plateau stress phase is more stable and gradual overall hardening is evident in the stress-strain curve. Under dynamic loading, the initial peak force and subsequent plateau force are elevated. There are three types of responses – quasi-static, transition/progressive and dynamic – depending on the magnitude of the impact velocity.

Collective invasion induced by an autocrine purinergic loop through connexin-43 hemichannels.

Progression of epithelial cancers predominantly proceeds by collective invasion of cell groups with coordinated cell-cell junctions and multicellular cytoskeletal activity. Collectively invading breast cancer cells express the gap junction protein connexin-43 (Cx43), yet whether Cx43 regulates collective invasion remains unclear. We here show that Cx43 mediates gap-junctional coupling between collectively invading breast cancer cells and, via hemichannels, adenosine nucleotide/nucleoside release into the extracellular space. Using molecular interference and rescue strategies, we identify that Cx43 hemichannel function, but not intercellular communication, induces leader cell activity and collective migration through the engagement of the adenosine receptor 1 (ADORA1) and AKT signaling. Accordingly, pharmacological inhibition of ADORA1 or AKT signaling caused leader cell collapse and halted collective invasion. ADORA1 inhibition further reduced local invasion of orthotopic mammary tumors in vivo, and joint up-regulation of Cx43 and ADORA1 in breast cancer patients correlated with decreased relapse-free survival. This identifies autocrine purinergic signaling, through Cx43 hemichannels, as a critical pathway in leader cell function and collective invasion.

Antiproliferative activity of the dibenzylideneacetone derivate (E)-3-ethyl-4-(4-nitrophenyl)but‑3-en-2-one in Trypanosoma cruzi

Chagas disease is one of the most prevalent neglected diseases in the world. The illness is caused by Trypanosoma cruzi, a protozoan parasite with a complex life cycle and three morphologically distinct developmental stages. Nowadays, the only treatment is based on two nitro-derivative drugs, benznidazole and nifurtimox, which cause serious side effects. Since the treatment is limited, the search for new treatment options for patients with Chagas disease is highly necessary. In this study we analyzed the substance A11K3, a dibenzylideneacetone (DBA). DBAs have an acyclic dienone attached to aryl groups in both β-positions and studies have shown that they have biological activity against tumors cells, bacteria, and protozoa such as T. cruzi and Leishmania spp. Here we show that A11K3 is active against all three T. cruzi evolutionary forms: the epimastigote (IC50 = 3.3 ± 0.8), the trypomastigote (EC50 = 24 ± 4.3) and the intracellular amastigote (IC50 = 9.3 ± 0.5 µM). A cytotoxicity assay in LLCMK2 cells showed a CC50 of 239.2 ± 15.7 µM giving a selectivity index (CC50/IC50) of 72.7 for epimastigotes, 9.9 for trypomastigotes and 25.9 for intracellular amastigotes. Morphological and ultrastructural analysis of the parasites treated with A11K3 by TEM and SEM revealed alterations in the Golgi complex, mitochondria, plasma membrane and cell body, with an increase of autophagic vacuoles and lipid bodies. Biochemical assays of A11K3-treated T. cruzi showed an increase of ROS, plasma membrane ruptures, lipid peroxidation, mitochondrial membrane depolarization with a decrease in ATP and accumulation of autophagic vacuoles. The results lead to the hypothesis that A11K3 causes death of the protozoan through events such as plasma membrane and mitochondrial alterations and autophagy, characteristic of cell collapse.

Synergistic Effect of Pseudolaric Acid B with Fluconazole Against Resistant Isolates and Biofilm of Candida tropicalis.

PurposeCandida tropicalis (C. tropicalis) has emerged as an important fungal pathogen due to its increasing resistance to conventional antifungal agents, especially fluconazole (FLC). Pseudolaric acid B (PAB), a herbal-originated diterpene acid from Pseudolarix kaempferi Gordon, has been reported to possess inhibitory activity against fungus. The present study aims to investigate the antifungal effect of PAB alone and in combination with FLC on planktonic and biofilm cells of C. tropicalis.MethodsThe antifungal activity of PAB against planktonic isolates was evaluated alone and in combination with FLC using the chequerboard microdilution method and growth curve assay. The anti-biofilm effects were quantified by tetrazolium (XTT) reduction assay, which were further confirmed by scanning electron microscopy (SEM) and fluorescent microscope to observe morphological changes of biofilm treated with PAB and FLC.ResultsIt was revealed that PAB alone exhibited similar inhibitory activity against FLC-resistant and FLC-susceptible strains with median MIC ranging from 8 to 16 µg/mL. When administered in combination, synergism was observed in all (13/13) FLC-resistant and (2/9) FLC-susceptible strains with FICI ranging from 0.070 to 0.375. Moreover, the concomitant use of PAB and FLC exhibited a strong dose-dependent synergistic inhibitory effect on the early and mature biofilm, eliminating more than 80% biofilm formation. SEM found that PAB, different from azoles, could significantly inhibit spore germination and destroy the cell integrity causing cell deformation, swelling, collapse and outer membrane perforation.ConclusionPAB was highly active against FLC-resistant isolates and biofilm of C. tropicalis, particularly when combined with FLC. These findings suggest that PAB may have potential as a novel antifungal agent with different targets from azole drugs.

Sealing performance and mechanical behavior of PEMFCs sealing system based on thermodynamic coupling

The reliability of sealing system is closely related to the work performance of PEMFCs. The model of steel-strip PEMFCs is established in this paper, the stress-strain distribution of sealing system in single-cell and multi-cells structures under three different working temperature were investigated. Effects of compression ratio, fluid pressure, dislocation and dimension of gasket on the sealing performance and mechanical behavior of PEMFCs were studied. The results show that the sealing performances of single-cell and multi-cells structures are similar under different working temperatures. Temperature has a great influence on the von-Mises stress of sealing system and the deformation of MEA frame. The research results of single-cell can be extended to the multi-cells, but the influence of temperature can't be ignored. With the increasing of compression ratio, fluid pressure and dimension, the sealing performance also be improved. Excessive dislocation may aggravate the deformation of MEA frame. The high stress area appears inside cross section which is prone to cause seal failure and full cells collapse.

Trichoderma Volatile Organic Compounds as a Biofumigation Tool against Late Blight Pathogen Phytophthora infestans in Postharvest Potato Tubers.

We tested the ability of 14 strains of Trichoderma to emit volatile compounds that decreased or stopped the growth of Phytophthora infestans. Volatile organic compounds (VOCs) emitted from Trichoderma strains designated T41 and T45 inhibited the mycelial growth of P. infestans grown on a laboratory medium by 80 and 81.4%, respectively, and on potato tubers by 93.1 and 94.1%, respectively. Using the DNA sequence analysis of the translation elongation factor region, both Trichoderma strains were identified as Trichoderma atroviride. VOCs emitted by the strains were analyzed, and 39 compounds were identified. The most abundant compounds were 3-methyl-1-butanol, 6-pentyl-2-pyrone, 2-methyl-1-propanol, and acetoin. Electron microscopy of the hyphae treated with T. atroviride VOCs revealed serious morphological and ultrastructural damages, including cell deformation, collapse, and degradation of cytoplasmic organelles. To our knowledge, this is the first report describing the ability of Trichoderma VOCs to suppress the growth of the late blight potato pathogen.

Histopathological evidence of concomitant sexual and asexual reproduction of Elsinoë ampelina in grapevine under subtropical climate

Anthracnose caused by Elsinoë ampelina is one of the most serious diseases affecting grapevine production worldwide. Previous studies have described many structural and histochemical changes in grapevine leaves associated with E. ampelina colonization and the presence of ascus-like structures in the lesions. In this paper, we characterized the colonization and reproduction of E. ampelina in grapevine tendrils, stems and berries using light, epifluorescence and scanning electron microscopy. In the early stages of colonization, shape changes and the collapse of epidermal and parenchyma cells were more pronounced in the center of lesions. At this stage, pectic substances accumulated inside the parenchyma cells and hyphae were observed colonizing tissues inter- and intracellularly, including tracheary elements. As colonization evolved, lesions enlarged and infected tissues became necrotic and collapsed. Tyloses and conidiogenous cells producing conidia were observed in the tracheary elements. Conidiogenous cells and conidia were also present on the lesion surface. On the same lesions, bitunicate asci containing two-to three-celled ascospores were observed on the surface and throughout the stromatic tissue. Our analyses showed that both sexual and asexual stages of E. ampelina occur from the beginning of the epidemic, which may help to explain the explosive nature of the disease when early stages of grapevine development coincide with rainy seasons.

Bioindicator potential of Ricinus communis to simulated rainfall containing potassium fluoride.

BackgroundFluoride pollution is a global problem because of its high phytotoxicity. Fluoride is released in air, water and soil through industrial processes, where it damages various plant species. Ricinus communis is widely distributed in Brazil, India and China and has been extensively used as a phytoremediation species in heavy metal-contaminated soils. However, few studies regarding the effect of air pollutants on R. communis have been published, and no information about the exposure of this species to fluoride is available. Therefore, the aim of the present study was to investigate the effects of fluoride on R. communis morphoanatomical and physiological responses using simulated rainfall containing potassium fluoride (KF).MethodsYoung plants at approximately 10 days after emergence were treated daily with KF using simulated rainfall at 0, 1.5, 3.0 and 4.5 mg L−1, for 37 consecutive days. Chlorophyll a fluorescence, gas exchange, anatomical characteristics and fluoride accumulation in the roots and leaves were evaluated after this period.ResultsNo visual or anatomical symptoms were observed for the first three treatments. Necrosis and chlorosis were visually evident after the 37th day of KF application at 4.5 mg L−1, followed by changes in parenchyma tissues, cell collapse and phenolic compound accumulation at the end of the experiment. No damage was observed in terms of photosynthetic photochemical and biochemical stages. Maintenance of physiological characteristics in the presence of fluoride accumulation in roots and leaves were shown to be important fluoride biomarkers. These characteristics suggest that R. communis is tolerant to 1.5 and 3.0 mg L−1 KF, and is anatomically sensitive at 4.5 mg L−1 KF.

Processed Bamboo as a Novel Formaldehyde-Free High-Performance Furniture Biocomposite.

We used an innovative approach involving hot pressing, low energy consumption, and no adhesive to transform bamboo biomass into a natural sustainable fiber-based biocomposite for structural and furniture applications. Analyses showed strong internal bonding through mechanical "nail-like" nano substances, hydrogen, and ester and ether bonds. The biocomposite encompasses a 10-fold increase in internal bonding strength with improved water resistance, fire safety, and environmentally friendly properties as compared to existing furniture materials using hazardous formaldehyde-based adhesives. As compared to natural bamboo material, this new biocomposite has improved fire and water resistance, while there is no need for toxic adhesives (mostly made from formaldehyde-based resin), which eases the concern of harmful formaldehyde-based VOC emission and ensures better indoor air quality. This surpasses existing structural and furniture materials made by synthetic adhesives. Interestingly, our approach can 100% convert discarded bamboo biomass into this biocomposite, which represents a potentially cost reduction alternative with high revenue. The underlying fragment riveting and cell collapse binding are obviously a new technology approach that offers an economically and sustainable high-performance biocomposite that provides solutions to structural and furniture materials bound with synthetic adhesives.

Wounding-induced changes in cellular pressure and localized auxin signalling spatially coordinate restorative divisions in roots

Wound healing in plant tissues, consisting of rigid cell wall-encapsulated cells, represents a considerable challenge and occurs through largely unknown mechanisms distinct from those in animals. Owing to their inability to migrate, plant cells rely on targeted cell division and expansion to regenerate wounds. Strict coordination of these wound-induced responses is essential to ensure efficient, spatially restricted wound healing. Single-cell tracking by live imaging allowed us to gain mechanistic insight into the wound perception and coordination of wound responses after laser-based wounding in Arabidopsis root. We revealed a crucial contribution of the collapse of damaged cells in wound perception and detected an auxin increase specific to cells immediately adjacent to the wound. This localized auxin increase balances wound-induced cell expansion and restorative division rates in a dose-dependent manner, leading to tumorous overproliferation when the canonical TIR1 auxin signaling is disrupted. Auxin and wound-induced turgor pressure changes together also spatially define the activation of key components of regeneration, such as the transcription regulator ERF115. Our observations suggest that the wound signaling involves the sensing of collapse of damaged cells and a local auxin signaling activation to coordinate the downstream transcriptional responses in the immediate wound vicinity.

Mechanical properties and energy absorption of FCC lattice structures with different orientation angles

The dynamic crushing behaviors of FCC lattice structures with various rotation angles are explored by numerical simulations. According to the localization band formed by the cell collapse, several deformation modes are distinguished. The effects of the orientation angle and the crushing velocity on the mechanical properties of the lattice are investigated. It is shown that the deformation mode depends strongly on the orientation angle and the impact velocity, which can be plotted on a mode classification map. It also indicates that there exists an optimal orientation angle of the FCC lattice structure which corresponds to the highest plateau stress and thus the best energy absorption capacity.

Evaporation of sessile ethanol-water droplets on a critically inclined heated surface

The evaporation of a binary sessile ethanol-water droplet on an inclined substrate is studied experimentally just below the critical sliding angles for different substrate temperatures. A customized goniometer equipped with a CMOS camera and an infrared (IR) camera is used. The droplet is observed to remain pinned in the advancing side during the evaporation process, while the receding side contracts. The asymmetry in the advancing and receding contact angles of the droplet on inclined substrate results in complex thermo-solutal Marangoni convection that is captured through IR images. The droplet exhibits two distinct oscillatory water-rich cold regions around the advancing contact line during the early stage of evaporation, while the more volatile and lighter ethanol creates a hotter and rapidly evaporating cell near the receding side. As ethanol evaporates away, the ethanol rich cells collapse producing thermal pulsations along the incline. Subsequently, the thermal patterns become similar to that of the pure-water droplet. It is also observed that the thermo-solutal driven oscillatory convection increases with increasing substrate temperature. Despite the complexity in convection dynamics, the evaporation rate exhibits a universal behavior in the normalized time at different substrate temperatures which can be represented by piecewise linear fits at the early and late stages of evaporation.

Dehydration as a possible tool to slow down peritoneal metastases by changing the intraperitoneal environment.

e16037 Background: Due to limited efficiency of current intravenous and intraperitoneal chemotherapeutic approaches, treating advanced peritoneal metastases (PM) remains an ongoing oncologic challenge. As the peritoneum is an optimal biological compartment for metastatic growth, stopping progressive tumor extension at more advanced stages is currently unachievable. With this study, we aim to investigate whether changing the intraperitoneal environment using dehydration might halt tumor progression. Methods: Commercially available human colon cancer cells (HT-29) were dehydrated for 15 minutes at 90% humidity and compared to cells treated with only oxaliplatin. Cell vitality was measured and structural cell changes following dehydration were analyzed via scanning electron microscopy. Additionally, staining with hematoxylin and eosin was performed on peritoneal tissue to assess dehydration effects using an ex vivo model. Finally, a mathematical model was established to measure dehydration of the abdominal compartment for feasibility evaluation. Results: Partial dehydration has a significant cytotoxic effect on colon cancer cells ( p< 0.05) even if only shortly applied. The addition of oxaliplatin treatment following dehydration results in highly reduced cell vitality ( p< 0.01). Sole dehydration vs. sole oxaliplatin application have similar effects. SEM revealed a cellular collapse of HT-29 cells caused by dehydration. Histopathological examination of peritoneal tissue demonstrated that the dehydration effect is superficial with penetration depths of < 200 µm. Conclusions: Our data indicate that dehydration is a potentially feasible technique with measurable cytotoxic effects on colorectal cancer cells. While changing the physiological milieu of the peritoneal cavity by means of dehydration could significantly reduce PM extent, the consequences of volume fluid loss must be equally considered. Thus, further studies are required to find a sustainable extent of dehydration while maintaining circulatory stability.

Lactoferrin Is Broadly Active against Yeasts and Highly Synergistic with Amphotericin B.

Lactoferrin (LF) is a multifunctional milk protein with antimicrobial activity against a range of pathogens. While numerous studies report that LF is active against fungi, there are considerable differences in the level of antifungal activity and the capacity of LF to interact with other drugs. Here we undertook a comprehensive evaluation of the antifungal spectrum of activity of three defined sources of LF across 22 yeast and 24 mold species and assessed its interactions with six widely used antifungal drugs. LF was broadly and consistently active against all yeast species tested (MICs, 8 to 64 μg/ml), with the extent of activity being strongly affected by iron saturation. LF was synergistic with amphotericin B (AMB) against 19 out of 22 yeast species tested, and synergy was unaffected by iron saturation but was affected by the extent of LF digestion. LF-AMB combination therapy significantly prolonged the survival of Galleria mellonella wax moth larvae infected with Candida albicans or Cryptococcus neoformans and decreased the fungal burden 12- to 25-fold. Evidence that LF directly interacts with the fungal cell surface was seen via scanning electron microscopy, which showed pore formation, hyphal thinning, and major cell collapse in response to LF-AMB synergy. Important virulence mechanisms were disrupted by LF-AMB treatment, which significantly prevented biofilms in C. albicans and C. glabrata, inhibited hyphal development in C. albicans, and reduced cell and capsule size and phenotypic diversity in Cryptococcus Our results demonstrate the potential of LF-AMB as an antifungal treatment that is broadly synergistic against important yeast pathogens, with the synergy being attributed to the presence of one or more LF peptides.

Gasdermin A3–Mediated Cell Death Causes Niche Collapse and Precocious Activation of Hair Follicle Stem Cells

Hair follicles undergo recurrent growth, regression, and resting phases throughout postnatal life, which is supported by hair follicle stem cells. The niche components of hair follicle stem cells are important to maintain their quiescence and stemness. Gsdma3 gain-of-function mutations in mice cause chronic skin inflammation, aberrant hair cycle, and progressive hair loss, reminiscent of scarring alopecia in humans. However, the mechanism underlying these defects remains elusive. Here, we used a combined Cre/loxP and rtTA/TRE system to study the spatiotemporal effect of Gsdma3 overexpression on distinct hair cycle stages. We found that Gsdma3-mediated cell death affects anagen initiation, anagen progression, and catagen-telogen transition. Induced Gsdma3 expression causes bulge inner layer collapse and precocious hair follicle stem cell activation, leading to subsequent hair follicle degeneration. Although macrophages and dendritic cells are recruited to the bulge region, invivo depletion of these cells using a neutralizing antibody does not alleviate cell death in the bulge or hair germ, indicating that macrophages are less likely to cause immediate hair follicle deletion. Our data suggest that dysregulated Gsdma3 causes bulge inner layer necrosis to induce club hair shedding and immediate anagen reentry without going through telogen morphology, which implicates a role for Gsdma3 in hair follicle stem cell niche maintenance.

Correlations between lignin content and structural robustness in plants revealed by X-ray ptychography

Lignin is a heterogeneous aromatic polymer responsible for cell wall stiffness and protection from pathogen attack. However, lignin represents a bottleneck to biomass degradation due to its recalcitrance related to the natural cell wall resistance to release sugars for fermentation or further processing. A biological approach involving genetics and molecular biology was used to disrupt lignin pathway synthesis and decrease lignin deposition. Here, we imaged three-dimensional fragments of the petioles of wild type and C4H lignin mutant Arabidopsis thaliana plants by synchrotron cryo-ptychography. The three-dimensional images revealed the heterogeneity of vessels, parenchyma, and fibre cell wall morphologies, highlighting the relation between disturbed lignin deposition and vessel implosion (cell collapsing and obstruction of water flow). We introduce a new parameter to accurately define cell implosion conditions in plants, and we demonstrate how cryo-ptychographic X-ray computed tomography (cryo-PXCT) provides new insights for plant imaging in three dimensions to understand physiological processes.

Leaf Morpho-anatomical Structure Determines Differential Response Among Restinga Species Exposed to Emissions from an Iron Ore Pelletizing Plant

An iron ore pelletizing plant in southeastern Brazil exposes the tropical coastal ecosystems known as restinga to emissions of dust, iron solid particulate matter, and sulfur dioxide (SO2). We aimed to assess the effects of those emissions on the leaf morphology and anatomy of the restinga species Byrsonima sericea, Cordia verbenacea, and Psidium guineense by evaluating visual symptomatology and analyzing the anatomical and micromorphological alterations resulting from exposure. Leaves were collected from individuals growing at two sites: a restinga forest fragment located 800 m away from the pelletizing plant and a restinga conservation unit 20 km away, which served as reference site. In all three species, individuals growing near the pelletizing plant showed necrotic regions on the leaf and foliar micromorphological alterations like turgor loss of epidermal cells, cuticle and epicuticular wax erosion, stomatal obliteration, and rupture and plasmolysis of trichomes. Anatomically, we found cell collapse, cell hypertrophy, and formation of a wound tissue. C. verbenacea showed the most severe visual and anatomical damage, being thus considered the most sensitive species to emissions. Leaf structural features such as uniseriate epidermis, lack of hypodermis, and presence of trichomes contributed to the highest sensitivity of C. verbenacea. Our findings reinforce the importance of performing morpho-anatomical studies to elucidate how leaf structure determines differential sensitivity to airborne pollutants in native species.

Comparative cytotoxic effects of five commonly used triazole alcohol fungicides on human cells of different tissue types

The widespread application of triazole fungicides makes people attach great concern over its adverse effects in mammalian. In this paper, cytotoxic effects of triazole alcohol fungicides (TAFs) were assessed on human HeLa, A549, HCT116 and K562 cells, and the potential mechanism of TAFs cytotoxicity was studied preliminarily. Results showed that TAFs had cytotoxicity on human cells with different level and cytotoxic selectivity. TAFs cytotoxicity was resonated with a typical hormetic biphasic dose action that produced a complex pattern of stimulatory or inhibitory effects on cell viability. Among the five TAFs, diniconazole revealed a widest range of cytotoxicity to inhibit the viability of the adherent and the suspension cells, causing HeLa cells shrinkage, A549 cells shrunken, and K562 cells collapse, and showed stronger cytotoxicity than hexaconazole. Moreover, the involvement of ROS generation in the cytotoxicity of TAFs on human cells was observed, and the apoptosis of HeLa cells and the formation of apoptotic body in K562 cells induced by diniconazole were characterized. The results indicated the cytotoxicity of TAFs with different structures on human cells was depended on their own property and cell specificity, K562 cells were the most susceptible to TAFs and diniconazole was the strongest toxic.

Microstructural characterization and constitutive modeling of deformation of closed-cell foams based on in situ x-ray tomography

Polymethacrylimide (PMI) foams own the highest specific stiffness and strength of all foams. In situ x-ray micro computed tomography (CT) is used to map three-dimensional (3D) microstructures of this representative closed-cell foam under quasi-static compression. The strain fields obtained via digital volume correlation reveal divergent types (discrete or spreading) of deformation banding for the PMI foam with different densities (52 or 75 kgm−3). Significant cell collapse occurs in the deformation bands, leading to ∼40% reduction of the mean cell size, and alignment of cell orientations. Microstructure-based finite element analysis confirms that elastic buckling of cell walls dominates cell collapse, and the buckling strength of walls depends highly on their thicknesses and inclination angles. An edge segmentation technique is then used to quantify the morphology and buckling strength index of cell walls. The spatial distribution of the weakest 3% cell walls correlates well with the modes of deformation banding. Based on elastic buckling of cell walls, new analytical models are developed to predict the strength–density scaling law and stress–strain curves of the PMI foam, which agree well with the experimental results.

Inductive quantification of energy absorption of high-density polyethylene foam for repeated blunt impact

Foams are used in a variety of impact energy absorption applications because of their ability to engage in large deformations under steady load transfer during the cell collapse. Quantification of the energy absorption capabilities of foams, including those resulting from repeated loading and unloading, is critical to both modeling and prototype development of systems utilizing these important materials. This paper details a novel process of characterizing a cross-linked high-density polyethylene foam for its applicability within helmet liners designed for low-velocity blunt impact. The foams are characterized using various forms of compression testing and physical measurements. The analyses include examination of the tangent modulus, strain hardness, energy absorption ideality, and energy absorption efficiency. Together, these analyses identify the regions of changing behavior of the nonlinear impact absorption material system. A case study for the materials is presented, which reveals that the examined high-density polyethylene foam exhibits some of the most efficient impact properties during the first impact. However, this case study also identifies that those impact properties can reduce significantly, e.g. a 55% increase in stress in the case of a 0.50 strain-level deformation in the first impact, for a subsequent impact after only a 120 s rest period. The novel combination of testing and analysis presented within this paper enables the developer of a foam energy absorption system to advance their interrogation of foams for repeated large strain deformations and temperature variations.