Cellular Structure Research Articles

Biomimetic surface design enables a resilient solid electrolyte interphase for high-performance anodes

Surface coating presents an effective methodology for mitigating the detrimental effects of large volume changes inherent to high-capacity anode materials (e.g. Si, SiOx). However, designs often prioritize the protection of internal active particles, inadvertently neglecting the intricate interplay between the coating layer and the external electrolyte which exhibits profound influences on the solid electrolyte interphases (SEIs). Inspired by the extracellular polymeric substance (EPS) protecting biological cells (e.g. yeast) from predation and chemical damages, we prepare a conducting polymer-based EPS system (CP-EPS) on a surface bilayer comprising soft carbon membranes and compact graphene walls, constructing the biomimetic cellular structure. The CP-EPS chemically interacts with electrolyte catalyzing the symbiosis of integrated LiF-enriched SEIs and physically provide sufficient resilience for SEIs. This resilient SEIs offer excellent reaction kinetics and roughness which protects the structural integrity of the particle and itself from pulverization and excessive SEI thickening. The prepared SiOx anode delivers a superior average coulombic efficiency of 99.4% over 200 cycles at 0.5C and a high reversible capacity of 730 mAh g-1 after 300 cycles at 2C.

On the work-hardening behaviour of the additively manufactured Al-Si-Mg alloys: composite-like versus networked microstructure

Al-Si-Mg alloys are widely used for manufacturing components via laser powder bed fusion in various industrial applications where ductility and the capacity to accommodate the strain hardening are key criteria. The ductility of the laser powder bed-fused Al alloys has become a crucial property due to their fine cellular microstructure. Post-processing heat treatments improve ductility, but resultant microstructural changes affect the work-hardening behaviour, deformability, and uniform elongation values. This study aims to investigate the work-hardening capability, uniform elongation and deformability of AlSi7Mg and AlSi10Mg samples after different post-processing heat treatments by using tensile tests, optical and scanning electron microscopies. At aging temperatures below 200°C, the fully cellular structure of eutectic Si governs both the work-hardening behaviour and the strengthening mechanisms, despite the precipitation phenomenon. When direct-aging temperatures exceed 200°C, the coarsening of the Si-eutectic network modifies work-hardening behavior (Stages 1-3), accentuating the effects induced by the precipitates. Artificial aging highlights the role of precipitates in controlling both work-hardening properties and deformability.

Sunflower pith inspired dual-gradient cellular polyurethane architecture with amplified mechanical functions

Artificial cellular materials with various mechanical functions are attracting increasing attentions from aerospace, transportation, and industrialization. However, many artificial cellular materials, despite of the hierarchically ordered structures and even unique performance to some, still lag behind many natural ones in amplification of mechanical functions owing to the limitations in intrinsic mechanical performance and sophisticated structural design. Herein, inspired with lightweight and high strength of sunflower piths, we proposed a dual-gradient structure consisting of pore size gradient and wall thickness gradient to engineer cellular architectures with desirable mechanical performance by harnessing vat photopolymerization 3D printing of double crosslinking networks polyurethane elastomer. The double-gradient cellular polyurethane architecture displays more exceptional capability in load-bearing and energy absorption compared with non– and single gradient structures. Besides, the specific compressive strength and energy absorption of the dual-gradient cellular architectures are 4 times higher than those of traditional mechanical metamaterial structures such as octet-truss lattice, gyroid lattice, and porous structure prepared with the same material. Potential mechanisms such as dual-gradient cellular structures to obtain selective flexural deformation behaviour increasing their energy absorption and dissipation capacity are fully elucidated. As the potential paradigms, we demonstrated the mechanical functions of biomimetic mechanical cellular architectures for efficient impact protection and noise isolation, which offered a promising perspective toward developing soft metamaterials with excellent mechanical functions for potential soft machines and engineering applications.

A novel adjunctive diagnostic method for bone cancer: Osteosarcoma cell segmentation based on Twin Swin Transformer with multi-scale feature fusion

BackgroundOsteosarcoma, the most common primary bone tumor originating from osteoblasts, poses a significant challenge in medical practice, particularly among adolescents. Conventional diagnostic methods heavily rely on manual analysis of magnetic resonance imaging (MRI) scans, which often fall short in providing accurate and timely diagnosis. This underscores the critical need for advancements in medical imaging technologies to improve the detection and characterization of osteosarcoma. MethodsIn this study, we sought to address the limitations of current diagnostic approaches by leveraging Hoechst-stained images of osteosarcoma cells obtained via fluorescence microscopy. Our primary objective was to enhance the segmentation of osteosarcoma cells, a crucial step in precise diagnosis and treatment planning. Recognizing the shortcomings of existing feature extraction networks in capturing detailed cellular structures, we propose a novel approach utilizing a twin swin transformer architecture for osteosarcoma cell segmentation, with a focus on multi-scale feature fusion. ResultsThe experimental findings demonstrate the effectiveness of the proposed Twin Swin Transformer with multi-scale feature fusion in significantly improving osteosarcoma cell segmentation. Compared to conventional techniques, our method achieves superior segmentation performance, highlighting its potential utility in clinical settings. ConclusionThe development of our Twin Swin Transformer with multi-scale feature fusion method represents a significant advancement in medical imaging technology, particularly in the field of osteosarcoma diagnosis. By harnessing advanced computational techniques and leveraging high-resolution imaging data, our approach offers enhanced accuracy and efficiency in osteosarcoma cell segmentation, ultimately facilitating better patient care and clinical decision-making.

Cytoskeletal mechanisms regulating attaching/effacing bacteria interactions with host cells: It takes a village to build the pedestal.

The actin cytoskeleton is a key cellular structure subverted by pathogens to infect and survive in or on host cells. Several pathogenic strains of Escherichia coli, such as enteropathogenic E. coli (EPEC) and enterohemorrhagic E. coli (EHEC), developed a unique mechanism to remodel the actin cytoskeleton that involves the assembly of actin filament-rich pedestals beneath the bacterial attachment sites. Actin pedestal assembly is driven by bacterial effectors injected into the host cells, and this structure is important for EPEC and EHEC colonization. While the interplay between bacterial effectors and the actin polymerization machinery of host cells is well-understood, how other mechanisms of actin filament remodelling regulate pedestal assembly and bacterial attachment are poorly investigated. This review discusses the gaps in our understanding of the complexity of the actin cytoskeletal remodelling during EPEC and EHEC infection. We describe possible roles of actin depolymerizing, crosslinking and motor proteins in pedestal dynamics, and bacterial interactions with the host cells. We also discuss the biological significance of pedestal assembly for bacterial infection.

A novel “reinforcing-foaming-recovering” strategy for achieving thermally insulating green foams with ultrafast degradation

Lightweight porous materials have garnered increasing attention in application domains of intelligent construction and flexible thermal insulation, owing to their customizable 3D porous structures and outstanding performances. Nonetheless, the severe environmental pollution resulting from the accumulation of non-degradable plastic waste in the ecosystem has sparked significant interest in developing bio-degradable thermal insulation foams. The preparation of biodegradable foam, however, typically requires operating specialized equipment for long periods under extreme conditions, which diminishes its environmental friendliness as claimed. Herein, we present a pioneering "Reinforcing-Foaming-Recovering" strategy to achieve ultralight and recyclable green foams with excellent thermal insulation properties. This innovative strategy, involving materials reinforcing and low-pressure foaming complemented by nitrogen-assisted gas recovering enables the preparation of low-density (0.08 g/cm3) biodegradable foams with restricted shrinkage ratio (<5%). Thanks to the easy-to-control foaming method, combined with the improved 3D network cellular structures caused by nitrogen-assisted gas exchange, the achieved green foams exhibit favorable thermal insulation (39.8 mW/m·K) and superior biodegradation efficiency (11.5%/2 months). The approach of energy-efficient nitrogen-assisted low-pressure foaming of degradable polymers offers a promising and practical solution for producing eco-friendly and multifunctional porous materials with economic advantages.

EVENING PRIMROSE OIL AS A DIETARY THERAPY AT DIFFERENT STAGES OF A WOMANS REPRODUCTIVE AGE

Introduction: Primrose or evening primrose, scientifically known as Oenothera biennis L, this small yellow flower has brown seeds from which an oil rich in essential fatty acids is extracted, in particular linoleic acid and y-linoleic acid. These are the reason for the use of evening primrose oil, as they have benefits in cellular structure, skin, metabolism, reproductive system, among others. Objective: To evaluate evening primrose oil as diet therapy in different stages of the reproductive age of women to determine its efficacy. Methodology: The search was based on a literature review and were examined for eligibility according to the inclusion criteria. Results: Essential fatty acids can be depleted during the menstrual cycle, leading to hormonal imbalance that causes most premenstrual symptoms. According to the benefits found in cervical preparation in pregnancy, they are related to the effects of misoprostol and evening primrose oil on prostaglandins. The last article found in this research deals with the relationship between the consumption of evening primrose oil and its possible benefits in the psychological symptoms that may appear in the climacteric syndrome (menopause). Discussion: According to the results obtained, further research is necessary to be sure of a probable alternative treatment with evening primrose oil.

Biologic Augmentation of Rotator Cuff Repair: Current Concepts Review.

Rotator cuff tears are common in an aging population. Thus far, primary repairs have shown high re-tear rates suggesting the need for improved healing modalities. Current augmentations of rotator cuff repairs include synthetic and biological scaffolds, surgical bone marrow venting, and infusing the repair with a variety of stem cells and growth factors aimed at restoring the native cellular structure and function of the repaired tissue. This current concepts review discusses the anatomy, physical presentation, diagnosis, and treatment of rotator cuff tears; biological adjuvants for rotator cuff repairs; and the current literature on outcomes after biologically augmented rotator cuff repairs. [Orthopedics. 202x;4x(x):xx-xx.].

Evolvability in Artificial Development of Large, Complex Structures and the Principle of Terminal Addition.

Epigenetic tracking (ET) is a model of development that is capable of generating diverse, arbitrary, complex three-dimensional cellular structures starting from a single cell. The generated structures have a level of complexity (in terms of the number of cells) comparable to multicellular biological organisms. In this article, we investigate the evolvability of the development of a complex structure inspired by the "French flag" problem: an "Italian Anubis" (a three-dimensional, doglike figure patterned in three colors). Genes during development are triggered in ET at specific developmental stages, and the fitness of individuals during simulated evolution is calculated after a certain stage. When this evaluation stage was allowed to evolve, genes that were triggered at later stages of development tended to be incorporated into the genome later during evolutionary runs. This suggests the emergence of the property of terminal addition in this system. When the principle of terminal addition was explicitly incorporated into ET, and was the sole mechanism for introducing morphological innovation, evolvability improved markedly, leading to the development of structures much more closely approximating the target at a much lower computational cost.

Recent advances in brain organoids: a comprehensive review of the last eight years

Organoids are three-dimensional cellular structures grown in vitro that can self-organize and differentiate into cell types with organ-specific functions, closely mimicking the biological properties of tissues and organs in vivo. Brain organoids, which differentiate into structures resembling brain function, serve as valuable models for medical research, including disease microenvironment simulation, brain mechanism exploration, and drug evaluation. In this review, we analyzed 808 articles retrieved from PubMed, CNKI, and Wanfang databases using the keyword "brain organoids," of which 180 were included. We summarized the research progress of brain organoids over the past eight years by categorizing and refining the findings. Our analysis shows that brain organoids have achieved significant success in simulating brain development in vitro, leading to the establishment and refinement of 3D brain organoid models for disease research. Brain organoids have been widely applied to explore disease-related mechanisms, yielding promising results and opening avenues for further research on the human brain. In this review, we summarize the progress of brain organoids in three areas: culture methods, disease-related research, and brain exploration.

Effects of Titanium Dioxide Nanoparticles on Chick Embryo: Immunomodulatory, Hepatic and Biochemical Alterations.

The utilization of titanium dioxide nanoparticles (TiO2 NPs) has significantly increased across various industries. This study rigorously explored the impact of TiO2 NPs exposure on chicken embryos, focusing particularly on alterations in the immune system, liver functionality and key biochemical markers. The study involved three groups of 30 eggs each, subjected to increasing doses of TiO2 NPs: Group C (control), Group T1 (150µg/mL) and Group T2 (300µg/mL). After 48h of incubation, the eggs in Groups T1 and T2 each received an injection of 0.3mL of the TiO2 NPs solution. In contrast, the eggs in the control group (Group C) were injected with 0.3mL of saline solution. Histopathological changes were analysed using haematoxylin and eosin (H&E) staining, whereas amniotic fluid's biochemical properties were examined photometrically. The study also assessed the expression of immune genes (AvBD9, IL6 and IL8L2) through quantitative PCR. The evaluations included growth metrics, amniotic fluid biochemistry and histological analysis of the liver, caecal tonsil and bursa of Fabricius. The results revealed subcutaneous haemorrhage, significant reductions in total body weight and marked changes in biochemical markers, including urea, creatinine, alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), in the amniotic fluid of the groups treated with TiO2 NPs, compared to the control. Histological examinations indicated noticeable alterations in the liver, caecal tonsil and bursa of Fabricius following TiO2 NP exposure. These alterations were characterized by disruptions in cellular structures and variations in lymphocyte counts. Furthermore, a notable decrease in the expression of immunity genes, namely, AvBD9, IL8L2 and IL6, was observed in the TiO2 NP-treated groups compared to the control. The findings underscore the need for risk assessments of TiO2 NPs exposure due to its impact on development and immunity. Future research should explore its impact on neurodevelopment and degeneration.

Quality control for single-cell analysis of high-plex tissue profiles using CyLinter.

Tumors are complex assemblies of cellular and acellular structures patterned on spatial scales from microns to centimeters. Study of these assemblies has advanced dramatically with the introduction of high-plex spatial profiling. Image-based profiling methods reveal the intensities and spatial distributions of 20-100 proteins at subcellular resolution in 103-107 cells per specimen. Despite extensive work on methods for extracting single-cell data from these images, all tissue images contain artifacts such as folds, debris, antibody aggregates, optical aberrations and image processing errors that arise from imperfections in specimen preparation, data acquisition, image assembly and feature extraction. Here we show that these artifacts dramatically impact single-cell data analysis, obscuring meaningful biological interpretation. We describe an interactive quality control software tool, CyLinter, that identifies and removes data associated with imaging artifacts. CyLinter greatly improves single-cell analysis, especially for archival specimens sectioned many years before data collection, such as those from clinical trials.

Transmission Electron Microscopy of Coral Tissue.

Coral reefs are invaluable ecosystems that are under threat from various anthropogenic stressors. There has been a recent increase in the diagnostic tools utilized to understand how these threats impact coral reef health. Unfortunately, the application of diagnostic tools like transmission electron microscopy (TEM) is not as standardized or developed in coral research as in other research fields. Utilizing TEM in conjunction with other diagnostic methods can aid in understanding the impact of these stressors on the cellular level because TEM offers valuable insight into the structures and microsymbionts associated with coral tissue that cannot be obtained with a conventional light microscope. Additionally, a significant amount of coral tissue ultrastructure has not yet been extensively described, causing a considerable gap in our understanding of cellular structures that could relate to the immune response, cellular function, or symbioses. Moreover, additional standardization is needed for TEM in coral research to increase comparability and reproducibility of findings across studies. Here, we present standardized TEM sample fixation, embedding, and sectioning techniques for coral studies that ensure consistent ultrastructural preservation and minimize artifacts, enhancing the reliability and accuracy of TEM observations. We also demonstrate that these TEM protocols allow for the observation and quantification of bacterial and viral-like particles within the coral tissue as well as the endosymbiotic microalgae, potentially providing insight into their interactions within coral cells and how they relate to overall coral health and resilience. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Primary fixation Basic Protocol 2: Decalcification Basic Protocol 3: Sample dissection, secondary fixation, dehydration, and embedding Basic Protocol 4: Sectioning and grid staining Basic Protocol 5: Imaging.

Revealing membrane integrity and cell size from diffusion kurtosis time dependence.

The nonmonotonic dependence of diffusion kurtosis on diffusion time has been observed in biological tissues, yet its relation to membrane integrity and cellular geometry remains to be clarified. Here we establish and explain the characteristic asymmetric shape of the kurtosis peak. We also derive the relation between the peak time , when kurtosis reaches its maximum, and tissue parameters. The peak shape and its position qualitatively follow from the adiabatic extension of the Kärger model onto the case of intra-cellular diffusivity time-dependence. This intuition is corroborated by the effective medium theory-based calculation, as well as by Monte Carlo simulations of diffusion and exchange in randomly and densely packed spheres for various values of permeability, cell fractions and sizes, and intrinsic diffusivity. We establish that is proportional to the geometric mean of two characteristic time scales: extra-cellular correlation time (determined by cell size) and intra-cellular residence time (determined by membrane permeability). When exchange is barrier-limited, the peak shape approaches a universal scaling form determined by the ratio . Numerical simulations and theory provide an interpretation of a specific feature of kurtosis time-dependence, offering a potential biomarker for in vivo evaluation of pathology by disentangling the functional (permeability) and structural (cell size) integrity in tissues. This is relevant as the time-dependent diffusion cumulants are sensitive to pathological changes in membrane integrity and cellular structure in diseases, such as ischemic stroke, tumors, and Alzheimer's disease.

Deciphering the Cell Surface Sugar-Coating via Biochemical Pathways.

Cell surface components, specifically glycans, play a significant role in several biological functions like cell structure, crosstalk between cells, and eventual target recognition of the cells for therapeutics. The dense layer of glycans, i. e., glycocalyx, could differ in taxon, species, and cell type. Glycans are coupled with lipids and proteins to form glycolipids, glycoproteins, proteoglycans, and glycosylphosphatidylinositol-anchored proteins, making their study challenging. However, understanding glycosylation at the cellular level is vital for fundamental research and advancing glycan-targeted therapy. Among different pathways, metabolic glycan labelling uses the natural metabolic processes of the cell to introduce abiotic functionality into glycan residues. The Bertozzi group pioneered metabolic oligosaccharide engineering using glycan salvage pathways to convert monosaccharides with unnatural modifications. This eventually results in the probe becoming part of the complex cellular glycan structures via click chemistry using copper. On the other hand, the boronic acid-based probe can recognise carbohydrates in a single step without any chemical modification of the surface. This review discusses the significance of glycans as biomarkers for different diseases and the necessity to evaluate them in situ within the physiological environment. The review also discusses the prospect of this field and its potential applications.

Improvement of Thermal Stability of Charges in Polylactic Acid Electret Films for Biodegradable Electromechanical Sensors.

Eco-friendly sensors fabricated from biocompatible and biodegradable materials are promising candidates for wearable and implantable electronics due to their environmental sustainability and biosafety. This article reports a fully biodegradable electromechanical sensor (FBES) utilizing a sandwich structure with macro ripple structured polylactic acid (PLA) electret films acting as sensitive layers and molybdenum (Mo) sheets serving as electrodes for a wearable device application. The stability of the space charge stored within the PLA film has been enhanced by introducing an internal cellular structure and improving the polarization process. A macro ripple structure of the PLA layer with higher deformation is a great guarantee for boosting the pressure sensitivity. The results indicate that inserting cell microstructures and optimizing the polarization process significantly improve the charge storage stability of PLA films by nearly 55%. This enhancement is attributed to several factors, including the extended charge drift path of the charges in cellular films, a synergy effect of surface charges, and "macroscopic" dipole charges distributed in the cells. The fabricated sensor achieves a high sensitivity of 1000 pC/kPa, a wide pressure detection range of 0.03-62.4 kPa, and satisfactory stability. Such sensors are not only sensitive to body movements but also to subtle physiological signals, satisfying the diverse needs of wearable healthcare. Importantly, all the composition materials of the sensor can be completely degraded after their service, aligning with the environmentally friendly principles of green development.

Quantitative evaluation of intensity fidelity of super-resolution reconstruction for structured illumination microscopy

Super-resolution structured illumination microscopy (SR-SIM) relies heavily on post-processing reconstruction to obtain high-quality SR images from raw data. Although many SIM reconstruction algorithms have been developed to recover fine cellular structures with high fidelity even from the noisy data, whether the pixel intensities of reconstructed SR images are still proportional to the original fluorescence intensity has been less explored. The linearity between the intensity before and after reconstruction is defined as the intensity fidelity. Here, we proposed a method to evaluate the reconstructed SR image intensity fidelity at different spatial frequencies. With the proposed metric, we systematically investigated the impact of the key factors on the intensity fidelity in the standard Wiener-SIM reconstructions with simulated data, then evaluated the intensity fidelity of the SR images reconstructed by representative open-source packages. Our work provides a reference for SR-SIM image intensity fidelity improvement.

Dapagliflozin mitigates cellular stress and inflammation through PI3K/AKT pathway modulation in cardiomyocytes, aortic endothelial cells, and stem cell-derived β cells

Dapagliflozin (DAPA), a sodium-glucose cotransporter 2 (SGLT2) inhibitor, is well-recognized for its therapeutic benefits in type 2 diabetes (T2D) and cardiovascular diseases. In this comprehensive in vitro study, we investigated DAPA’s effects on cardiomyocytes, aortic endothelial cells (AECs), and stem cell-derived beta cells (SC-β), focusing on its impact on hypertrophy, inflammation, and cellular stress. Our results demonstrate that DAPA effectively attenuates isoproterenol (ISO)-induced hypertrophy in cardiomyocytes, reducing cell size and improving cellular structure. Mechanistically, DAPA mitigates reactive oxygen species (ROS) production and inflammation by activating the AKT pathway, which influences downstream markers of fibrosis, hypertrophy, and inflammation. Additionally, DAPA’s modulation of SGLT2, the Na+/H + exchanger 1 (NHE1), and glucose transporter (GLUT 1) type 1 highlights its critical role in maintaining cellular ion balance and glucose metabolism, providing insights into its cardioprotective mechanisms. In aortic endothelial cells (AECs), DAPA exhibited notable anti-inflammatory properties by restoring AKT and phosphoinositide 3-kinase (PI3K) expression, enhancing mitogen-activated protein kinase (MAPK) activation, and downregulating inflammatory cytokines at both the gene and protein levels. Furthermore, DAPA alleviated tumor necrosis factor (TNFα)-induced inflammation and stress responses while enhancing endothelial nitric oxide synthase (eNOS) expression, suggesting its potential to preserve vascular function and improve endothelial health. Investigating SC-β cells, we found that DAPA enhances insulin functionality without altering cell identity, indicating potential benefits for diabetes management. DAPA also upregulated MAFA, PI3K, and NRF2 expression, positively influencing β-cell function and stress response. Additionally, it attenuated NLRP3 activation in inflammation and reduced NHE1 and glucose-regulated protein GRP78 expression, offering novel insights into its anti-inflammatory and stress-modulating effects. Overall, our findings elucidate the multifaceted therapeutic potential of DAPA across various cellular models, emphasizing its role in mitigating hypertrophy, inflammation, and cellular stress through the activation of the AKT pathway and other signaling cascades. These mechanisms may not only contribute to enhanced cardiac and endothelial function but also underscore DAPA’s potential to address metabolic dysregulation in T2D.Graphical abstract

The Role and Interactive Mechanism of Endoplasmic Reticulum Stress and Ferroptosis in Musculoskeletal Disorders

Endoplasmic reticulum (ER) stress is a cellular phenomenon that arises in response to the accumulation of misfolded proteins within the ER. This process triggers the activation of a signalling pathway known as the unfolded protein response (UPR), which aims to restore ER homeostasis by reducing protein synthesis, increasing protein degradation, and promoting proper protein folding. However, excessive ER stress can perturb regular cellular function and contribute to the development of diverse pathological conditions. As is well known, ferroptosis is a kind of programmed cell death characterized by the accumulation of lipid peroxides and iron-dependent reactive oxygen species (ROS), resulting in oxidative harm to cellular structures. In recent years, there has been increasing evidence indicating that ferroptosis occurs in musculoskeletal disorders (MSDs), with emerging recognition of the complex relationship between ER stress and ferroptosis. This review presents a summary of ER stress and the ferroptosis pathway. Most importantly, it delves into the significance of ER stress in the ferroptosis process within diverse skeletal or muscle cell types. Furthermore, we highlight the potential benefits of targeting the correlation between ER stress and ferroptosis in treating degenerative MSDs.

Ultrastructural investigation of the posterior hyaloid membrane in posterior vitreous detachment.

Separation of the posterior hyaloid membrane (PHM) from the retina in posterior vitreous detachment (PVD) is a fundamental, but poorly understood, process underlying vitreoretinal disorders including retinal detachment and macular hole. We performed electron microscopy studies of the PHM after PVD to investigate its ultrastructure, associated cellular structures and relationship to the internal limiting membrane (ILM). Post-mortem human eyes were collected from recently deceased patients over 70 years of age. A posterior scleral button was trephined to identify PVD status, and the PHM and vitreous prepared for analysis with transmission and scanning electron microscopy. Twelve eyes from six patients were collected. Seven eyes had PVD; five eyes had attached vitreous. PHM was isolated from seven of seven eyes with PVD. The PHM in eyes with PVD is a laminar lacy sheet, distinct from the disorganised fibres of vitreous gel. Eyes without PVD had vitreous encased in internal limiting membrane which had separated en bloc from the retina. Cells embedded in the PHM (laminocytes) were identified in five of seven eyes with PVD, with strands stretching into the membrane. PHM isolated from eyes with PVD is distinct from artefactual separation of the ILM from the retina during dissection. PHM is ultrastructurally distinct from vitreous gel and is a separate entity. The en face appearance of PHM is similar to that of ILM, suggesting that in PVD, PHM forms from separation of an inner layer of ILM. Laminocytes may play a role in the pathogenesis of vitreoretinal disease.