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Dendritic poly(amide-urea)s from the first to fourth generations with a very narrow molecular weight distribution were prepared from 1,1,1-tris(4-carboxymethyloxyphenyl)ethane as a core molecule, using aminodicarboxylic acid and aminodicarbonyl azide as two AB2 monomers in a one-pot procedure. This procedure involves activation of end carboxyl groups with a condensing agent, diphenyl(2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate, condensation of the active amide with aminodicarbonyl azide, the Curtius rearrangement in the presence of aminodicarboxylic acid, and, finally, capping of the end groups with p-tert-butylaniline. All dendritic polymers were obtained quantitatively and fully characterized by elemental analysis and IR and NMR spectroscopies. Number average molecular weights (Mn) of dendritic poly(amide-urea)s were estimated by end group analysis, and each dendritic poly(amide-urea) had Mn close to the calculated value. Degrees of branching for the second and third generation dendritic polymers were found to be 0.93 and 0.90, respectively by ¹H NMR spectroscopy.

The syntheses of two AB2 monomers, aminodicarboxylic acid (1) and aminodicarbonyl azide (2), and their model reactions for the one-pot synthesis of dendritic aromatic poly(urea-amide)s using the two AB2 monomers were carried out. The model reaction of 2 and p-tolyl isocyanate produced the target urea with two acyl azide groups in 93% yield at 25 °C for 30 min in tetrahydrofuran (THF). The Curtius rearrangement from an acyl azide to an isocyanate was completed at 140 °C for 30 min in THF. The isocyanate produced via the Curtius rearrangement readily reacted with aniline to give a urea compound in 93% yield. p-Tolyl isocyanate selectively reacted with an amine group of 1 to give a urea with end carboxylic acid groups. The end carboxylic acid groups of the urea could be activated with a condensing agent, diphenyl(2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate (DBOP), and the condensation of the active amide with 2 provided an amide with acyl azide end groups.

We present a male autopsied case of chondrodysplasia punctata with abnormal face, symmetrical proximal limb shortness, severe psychomotor developmental delay, respiratory muscle weakness, and death at the age of 2 years. Although his clinical manifestations were similar to those of rhizomelic chondrodysplasia punctata (RCDP), biochemical studies using skin fibroblasts did not document the peroxisomal dysfunction described in RCDP. In addition, the sterol profile, for which abnormalities have recently been reported in cases of X-linked dominant form chondrodysplasia punctata (CDPX2), was normal both in the liver and in the fibroblasts. This patient may represent a new lethal form of chondrodysplasia punctata. © 2001 Wiley-Liss, Inc.

Micro separated composite polymer particles comprising of poly(dimethylsiloxane) (PDMS) and poly(butadiene) (PB) were prepared by an emulsifier-free seeded emulsion polymerization of butadiene with a radical initiator in the presence of a PDMS latex. The following three factors controlled the morphology of the particles: (i) cross-linking degree of PDMS; (ii) cross-linking degree of PB; and (iii) source of polymerization initiator. By decreasing the cross-linking degree of PDMS or PB, we obtain segregated PB from PDMS. An initiation system consisting of tert-butyl peroxylaurate and ferrous sulfate gave the hemispherical morphology in contrast to the core shell for potassium persulfate. Styrene and acrylonitrile were able to graft onto the PB phase of the particles with high efficiency. The corrections between the morphology of the composite polymer particles and the practical properties of poly(styrene-co-acrylonitrile)-modified graft polymers were also discussed.

An autopsied patient with Menkes' kinky hair disease, who showed unusually long survival until the age of five years with typical neuropathological changes, was examined for distribution of neuronal depletion in the cerebral cortex, and the cerebellar changes were compared morphologically and immunohistochemically with those found in a younger patient (1 year 8 months old) reported previously. Neuronal loss in the cerebral cortex in the both cases, which was illdefined and unassociated with gliosis, was preferentially distributed in the fifth and sixth layers, especially of the gyral bottom in almost all lobes in the older case. Therefore, this change was thought to be secondary to local ischemia caused by mechanical distortion at the stage of gyrus formation in addition to abnormal development. Ultrastructurally, a prominent increase of confronting cisternae (CC) complexes was found in the perikaryon and processes of Purkinje cells in both cases, and in the older patient CC complexes were arranged more densely and were transformed into concentric lamellar structures in the swollen dendrites. Immunohistochemically, the stainability of neurofilaments (NF, 200 kDa) in Purkinje cells, with or without somatic sprouts was faint or negative in the older patient compared with the marked or moderate positivity in the younger patient and age-matched controls. Empty baskets were absent and NF-positive axonal terminals and synaptophysin-positive granules on Purkinje cells were markedly decreased in both cases. These changes suggest that Purkinje cells degenerate progressively with time and that basket cells also are simultaneously involved.

A progressive neuromuscular syndrome developed in a girl suffering from fatal familial intrahepatic cholestasis (Byler disease). The neuromuscular syndrome included muscular wasting of the legs, pes cavus, areflexia, decreased vibratory sensation, cerebellar symptoms, ophthalmoplegia, and visual disturbance with retinitis pigmentosa. The serum vitamin E level was extremely low. Postmortem neuropathologic study revealed the following lesions: (1) Systemic axonopathy involving the peripheral nerves and proximal axons of the dorsal root ganglia and posterior roots as well as the distal axons of the central nervous system (CNS) (2) Neuronal loss in the sensory and oculomotor nuclei of the brain stem, basal ganglia, Clarke's column, posterior horn, and dorsal root ganglia. (3) Neuronal lipofuscinosis. Axonopathy was severer in the more distal axonal segments, although the cuneate fasciculus was more affected than the gracile fasciculus. The severity of neuronal lipofuscinosis was not correlated with that of neuronal disintegration. The electron-dense bodies in the dystrophic swollen axons resembled lipofuscin granules. These neuropathologic lesions were considered to be the sequelae to chronic vitamin E deficiency.

Submicron-size composite polymer particles consisting of polydimethylsiloxane/core and polybutadiene/shell were synthesized by seeded emulsion polymerization. The morphologies of composite particles were affected by polybutadiene ratio in the composite particles. Highly grafted polymer by poly(styrene-co-acrylonitrile) could be prepared by using the composite particles containing polybutadiene with polymerizable group. The morphologies of the grafted polymer were influenced by the morphologies of composite particles and the kinds of grafting initiators. It was found that surface gloss and lubricity of the graft polymers were influenced by morphologies of composite particles.

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