The Gag polyprotein is the main retroviral structural protein and is essential for the assembly and release of virus particles. In this study, we have analyzed the morphology and Gag stoichiometry of human T-cell leukemia virus type 1 (HTLV-1)-like particles and authentic, mature HTLV-1 particles by using cryogenic transmission electron microscopy (cryo-TEM) and scanning transmission electron m...

PURPOSE To investigate long-term ultrastructural changes in the retina after internal limiting membrane (ILM) peeling through the examination of morphologic changes 3 years after vitrectomy in cynomolgus monkeys. DESIGN Laboratory investigation. METHODS Pars plana vitrectomy was performed, followed by ILM peeling, in 2 primate eyes. Ultrastructural changes were investigated using light micr...

We derive an expression for the polarizability of an ellipsoidally shaped cell-like structure at field frequencies where membrane molecular resonances (vibrational and electronic) are important. We first present analytical results for the dielectric function of a flat, dipole coupled, bilayer consisting of molecules with one prominent resonance frequency. Due to the nature of the dipole couplin...

Reducing the internal pH of cultured cells by several different protocols that block endocytosis is found to alter the structure of clathrin lattices on the inside of the plasma membrane. Lattices curve inward until they become almost spherical yet remain stubbornly attached to the membrane. Also, the lattices bloom empty "microcages" of clathrin around their edges. Correspondingly, broken-open...

The initial events during phagocytosis of latex beads by mouse peritoneal macrophages were visualized by high-resolution electron microscopy of platinum replicas of freeze-dried cells and by conventional thin-section electron microscopy of macrophages postfixed with 1% tannic acid. On the external surface of phagocytosing macrophages, all stages of particle uptake were seen, from early attachme...

The effects of selected membrane, plate and flat shell finite element formulations on optimal topologies are numerically investigated. Two different membrane components are considered. The first is a standard 4-node bilinear quadrilateral, and the other is a 4-node element accounting for in-plane (drilling) rotations. Plate elements selected for evaluation include discrete Kirchhoff quadrilater...

Epidermal growth factor (EGF) receptor (EGFR) modulates mitosis and apoptosis through signalling by its high-affinity (HA) and low-affinity (LA) EGF-binding states. The prevailing model of EGFR activation derived from X-ray crystallography involves the transition from tethered ectodomain monomers to extended back-to-back dimers and cannot explain these EGFR affinities or their different functio...

Introduction The membranes of the inferior division of the labyrinth in some mammals appear more vulnerable to hydropic distention than those of the superior division. This finding in guinea pigs, cats, and humans has been attributed to the evidently thinner membranes with implied higher stress levels. Objective The objective of this study is to identify other configurational features, if any, ...