The touching of fibrillar surfaces elicits a broad range affective reactions, which from the adverse stinginess stiff bristle brush to pleasant feel velvet. To study tactile perception model surfaces, unique set samples carrying dense, regular arrays cylindrical microfibrils with high aspect ratio made different elastomer materials have been created. Fibril length and material compliance are va...

Symmetrical, extracellular fibrils, which are related to the "special fibrils" of the dermis described by Palade and Farquhar, have been found along the outer surface of the basement membrane covering the notochord in the tail of Rana catesbeiana (bullfrog) tadpoles. The fibrils are approximately 7,500 A long and occur singly or in clusters. The single fibrils are characterized by a symmetrical...

The inverse scattering problem is based on the scattering theory in physics, where measured data such as radiation from an object is used to determine the unique structure of the object in question. This approach has been widely successful in fields ranging from geophysics and medical imaging, to quantum field theory. In 1996 Henrik Flyvbjerg suggested that a similar approach could be used to s...

Collagen is most abundant in animal tissues as very long fibrils with a characteristic axial periodic structure. The fibrils provide the major biomechanical scaffold for cell attachment and anchorage of macromolecules, allowing the shape and form of tissues to be defined and maintained. How the fibrils are formed from their monomeric precursors is the primary concern of this review. Collagen fi...

The impact of estrogen depletion and drug treatment on type I collagen fibril nanomorphology and collagen fibril packing (microstructure) was evaluated by atomic force microscopy (AFM) using an ovariectomized (OVX) rabbit model of estrogen deficiency induced bone loss. Nine month-old New Zealand white female rabbits were treated as follows: sham-operated (Sham; n = 11), OVX + vehicle (OVX + Veh...

Palade and Farquhar (1) have recently reported the presence of a unique fibril in the skin of Amphibia and, in less well developed form, in various sites in the rat. Previous to that report, Brody (2) and Younes (3) observed similar fibrils in human skin and cervix, respectively, but did not emphasize their unusual character. Recent observations in our laboratory indicate that a similar fibril ...

An unusual protein AR was isolated from the amyloid fibril preparation derived from a patient with primary amyloidosis. Protein AR was unique in its antigenicity, and revealed no structural identity with any known amyloid proteins or with immunoglobulin chains or fragments. Thus a new third class of amyloid fibril proteins besides the immunoglobulin light-chain variable region fragments and the...

The aggregation of the protein tau into amyloid fibrils is known to be involved in the causation of the neurodegenerative tauopathies and the progression of cognitive decline in Alzheimer's disease. This review surveys the mechanism of tau aggregation with special emphasis on the information obtained from biochemical and biophysical studies. First, tau is described from a structure-function per...

We present a general mathematical theory for the mechanical interplay in tissue-equivalents (cell-populated collagen gels): Cell traction leads to compaction of the fibrillar collagen network, which for certain conditions such as a mechanical constraint or inhomogeneous cell distribution, can result in inhomogeneous compaction and consequently fibril alignment, leading to cell contact guidance,...