Multifunctional Supramolecular Dendrimers with ans-Triazine Ring as the Central Core: Liquid Crystalline, Fluorescence and Photoconductive Properties

We explore the formation of polar smectic clusters and the effects of the chemical structure on the phase formation in novel hockey-stick liquid crystalline materials derived from 4-cyanoresorcinol as the central core unit.

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Supramolecular liquid crystalline dendrimers with a porphyrin core and functional carboxylic acid dendrons

RSC Advances ◽

10.1039/c6ra13604d ◽

2016 ◽

Vol 6 (69) ◽

pp. 65179-65185 ◽

Cited By ~ 10

Author(s):

Alberto Concellón ◽

Madalina Bucoş ◽

José Luis Serrano ◽

Pilar Romero ◽

Mercedes Marcos

Keyword(s):

Carboxylic Acid ◽

Self Assembly ◽

Liquid Crystalline ◽

Photoluminescence Properties ◽

Smectic Mesophase ◽

Supramolecular Dendrimers ◽

Porphyrin Core ◽

Liquid Crystalline Dendrimers

Supramolecular dendrimers prepared via H-bonding between porphyrin core and bifunctionalised dendrons, incorporated in the periphery, display photoluminescence properties and self-assembly into smectic mesophase.

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Rational Design of the First Spherical Supramolecular Dendrimers Self-Organized in a Novel Thermotropic Cubic Liquid-Crystalline Phase and the Determination of Their Shape by X-ray Analysis

Journal of the American Chemical Society ◽

10.1021/ja963295i ◽

1997 ◽

Vol 119 (7) ◽

pp. 1539-1555 ◽

Cited By ~ 343

Author(s):

V. S. K. Balagurusamy ◽

G. Ungar ◽

V. Percec ◽

G. Johansson

Keyword(s):

Crystalline Phase ◽

Rational Design ◽

Liquid Crystalline ◽

Liquid Crystalline Phase ◽

X Ray ◽

Self Organized ◽

Supramolecular Dendrimers

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Freeze fracture imaging and computer simulation of liposome structure: Membrane geometry and defects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076834 ◽

1983 ◽

Vol 41 ◽

pp. 646-647

Author(s):

Joseph A. Zasadzinski

Keyword(s):

Liquid Crystalline ◽

Freeze Fracture ◽

Continuum Theory ◽

Closed Surfaces ◽

Straight Line ◽

Low Weight ◽

Concentric Spheres ◽

Membrane Geometry ◽

Dupin Cyclides ◽

Limiting Case

At low weight fractions, many surfactant and biological amphiphiles form dispersions of lamellar liquid crystalline liposomes in water. Amphiphile molecules tend to align themselves in parallel bilayers which are free to bend. Bilayers must form closed surfaces to separate hydrophobic and hydrophilic domains completely. Continuum theory of liquid crystals requires that the constant spacing of bilayer surfaces be maintained except at singularities of no more than line extent. Maxwell demonstrated that only two types of closed surfaces can satisfy this constraint: concentric spheres and Dupin cyclides. Dupin cyclides (Figure 1) are parallel closed surfaces which have a conjugate ellipse (r1) and hyperbola (r2) as singularities in the bilayer spacing. Any straight line drawn from a point on the ellipse to a point on the hyperbola is normal to every surface it intersects (broken lines in Figure 1). A simple example, and limiting case, is a family of concentric tori (Figure 1b).To distinguish between the allowable arrangements, freeze fracture TEM micrographs of representative biological (L-α phosphotidylcholine: L-α PC) and surfactant (sodium heptylnonyl benzenesulfonate: SHBS)liposomes are compared to mathematically derived sections of Dupin cyclides and concentric spheres.

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Ulcerogenic Tumors of the Pancreas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100676 ◽

1968 ◽

Vol 26 ◽

pp. 186-187

Author(s):

J. C. Garancis ◽

J. F. Kuzma ◽

S. D. Wilson ◽

E. H. Ellison

Keyword(s):

Endoplasmic Reticulum ◽

Tumor Cells ◽

Islet Cell ◽

Disease Process ◽

Central Core ◽

Islet Cell Tumors ◽

Opaque Zone ◽

Granular Form ◽

Zollinger Ellison Syndrome

It has been proposed that a gastrin-like hormone elaborated by non-beta islet tumors of the pancreas may be responsible for a fulminating ulcer diathesis. Subsequently, a potent gastric secretagogue was isolated from ulcerogenic tumors of the pancreas. This disease process is known now as “Zollinger-Ellison syndrome”.In our studies of two cases of Zollinger-Ellison syndrome, pancreatic lesions were identified as alpha islet cell tumors (Fig. 1). Tumor cells were fairly uniform. The sizes of the alpha granules were not significantly different, but their number and distribution varied greatly from one cell to another. Each granule consisted of a round, highly dense central core, separated from the limiting membrane by an opaque zone. The granular form of the endoplasmic reticulum was particularly prominent. Numerous mitochondria, round or elongated, were dispersed throughout the cytoplasm. Individual or clusters of lysosomes were observed in the majority of cells.

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