Morphology and Growth Behaviour of Myelin Figures of Lecithin

Sakurai, I.; Kawamura, Y.; Sakurai, Tosio; Ikegami, Akira; Seto, Tsuneo

doi:10.1080/00268948508079512

Cited by 37 publications

(25 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The structural features of myelin figures are very similar to that of the nerve myelin sheath (from which the name myelin was taken) and bilayers are very similar to bio-membranes [8]. By changing the texture of the lamellar phase to the onion phase (consists of closely packed multilamellar vesicles) by shearing it is possible to suppress myelin growth [2].…”

Section: Introductionmentioning

confidence: 63%

See 1 more Smart Citation

Myelin growth and initial dynamics

Dave

Surve

Manohar

et al. 2003

Journal of Colloid and Interface Science

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 63%

“…Myelin figures in phosphatidylcholine and a water system have been studied in great detail [3][4][5][6][7][8][9]. The structural features of myelin figures are very similar to that of the nerve myelin sheath (from which the name myelin was taken) and bilayers are very similar to bio-membranes [8].…”

Section: Introductionmentioning

confidence: 85%

Myelin growth and initial dynamics

Dave

Surve

Manohar

et al. 2003

Journal of Colloid and Interface Science

View full text Add to dashboard Cite

“…To ensure 2D analysis, the surfactant lump was pressed with the coverslip to produce a thin surfactant slice. The resulting myelins were 3-6 µm in diameter while previously myelins of 20 µm have been reported by Sakurai et al [2]. This clearly shows that myelin formation and growth adapt to the available environment such as height of cell.…”

Section: Resultsmentioning

confidence: 62%

“…Sakurai et al [2] investigated the growth behavior and morphological features of myelin figures in egg-yolk lecithin by microscopic observation at room temperature quantitatively. They concluded that in terms of morphological evolution, the myelin growth process is a three-step process.…”

Section: Introductionmentioning

confidence: 99%

Extended time range modeling of myelin growth

Taribagil¹,

Arunagirinathan²,

Manohar³

et al. 2005

Journal of Colloid and Interface Science

View full text Add to dashboard Cite

“…Due to the similarity of their structural features to those of nerve myelin sheaths, these tubules are often referred as "myelin tubes" or "myelin figures". The morphological features of myelin tubes have been classified into two steps according to the time of growth [3]. During the first step, simple tubes grow into bulk water with an initial growth rate in length about 1 µm/sec.…”

mentioning

confidence: 99%

Instability of myelin tubes under dehydration: Deswelling of layered cylindrical structures

et al. 2001

View full text Add to dashboard Cite

We report experimental observations of an undulational instability of myelin figures. Motivated by this, we examine theoretically the deformation and possible instability of concentric, cylindrical, multi-lamellar membrane structures. Under conditions of osmotic stress (swelling or dehydration), we find a stable, deformed state in which the layer deformation is given by δR ∝ r √ B A /(hB) , where BA is the area compression modulus, B is the inter-layer compression modulus, and h is the repeat distance of layers. Also, above a finite threshold of dehydration (or osmotic stress), we find that the system becomes unstable to undulations, first with a characteristic wavelength of order √ ξd0, where ξ is the standard smectic penetration depth and d0 is the thickness of dehydrated region.PACS numbers: PACS numbers: 87.22. Bt, 68.15.+e The swelling of bulk phospholipid by water at a temperature higher than the chain melting temperature can lead to the growth of multilayer lipid tubules from the interface of bulk lipid and water [1,2,3,4,5]. These tubules are of mesoscopic dimensions with a diameter about 20-40 µm. They have the symmetry of a smectic-A liquid crystal and a strong optical anisotropy. Both electron microscopy [6] and X-ray diffraction show a concentric multilayer structure of these lipid tubes with a layer spacing about 60Å [7]. Due to the similarity of their structural features to those of nerve myelin sheaths, these tubules are often referred as "myelin tubes" or "myelin figures". The morphological features of myelin tubes have been classified into two steps according to the time of growth [3]. During the first step, simple tubes grow into bulk water with an initial growth rate in length about 1 µm/sec. The diameter and number of layers of tubes appear to remain constant during this process and the growth rate is inversely proportional to the square root of growth time [2,4]. The growth almost stops in the second step which is characterized by the formation of complicated morphologies of myelin tubes, such as helical and coiling forms, apparently in order to maximize their inter-membrane attraction [8].In our experiments, we have observed an instability of myelin tubes under dehydration by isolating a single myelin tube from others (during the first step, as shown in Fig. 1) and allowing the bulk water to evaporate in a controlled open chamber. During this dehydration step, periodic bumps with a wavelength about 1 µm are observed on the surface of myelin tubes as shown in Fig. 2(a). As water further evaporates, these bumps grow into arms, as shown in Figs. 2(b) and 2(c), and a similar instability can occur for these long arms. As far as we know, this is the first reported observation of the instability of myelin tubes under dehydration. After the bulk water dries out, the tubular structure of myelins disappear and a mosaic structure is observed. Although the full structural change of myelin tubes under dehydration is very complicated and highly nonlinear, the initial instability of myelin tubes under...

show abstract

Morphology and Growth Behaviour of Myelin Figures of Lecithin

Cited by 37 publications

References 10 publications

Myelin growth and initial dynamics

Myelin growth and initial dynamics

Extended time range modeling of myelin growth

Instability of myelin tubes under dehydration: Deswelling of layered cylindrical structures

Contact Info

Product

Resources

About