Guest control of a hydrogen bond-catalysed molecular rotor.

Herein, the control of a molecular rotor using hydrogen bonding guests is demonstrated. With a properly positioned phenol substituent, the N-arylimide rotors can form an intramolecular hydrogen bond that catalyses the rotational isomerization process. The addition of the guests disrupts the hydrogen bond and raises the rotational barrier, slowing the rotation by two orders of magnitude.

Guest-accelerated molecular rotor.

A molecular rotor was designed in which the rate of rotation is accelerated by guest complexation. The binding of an acetate guest to the urea groups lowers the barrier of the adjacent C(aryl)-N(imide) bond by 2 to 4 kcal/mol. This behavior is in contrast to most molecular rotors in which guest complexation slows rotation.

Molecular playdough: conformationally programmable molecular receptors based on restricted rotation.

A new method for rapidly tailoring molecular properties is presented in which the three-dimensional shape of a malleable framework is controlled by heating with a template molecule.

A small molecule diacid with long-term chiral memory.

A small, axially chiral diacid was designed with chiral memory based on restricted rotation. Heating a racemic sample with a chiral alkaloid led to an enantiomeric excess of up to 40% ee. The guest-induced chirality was preserved on cooling to rt, which was maintained even in the absence of guest (t(1/2) = 14y).

Aggressive digital papillary adenocarcinoma: a report of two diseases and review of the literature.

Aggressive digital papillary adenocarcinoma (ADPAca) is a rare, underreported, and often misdiagnosed malignant tumor of the sweat glands most commonly occurring in males in their fifties to seventies. We report two cases of ADPAca with important clinical implications. A 54-year-old man presented 3 years after digit amputation for ADPAca with new blue nodules on his arm, lymphadenopathy, and a lung nodule; he was diagnosed with and treated for metastatic ADPAca.

Origins of selectivity in a colorimetric charge-transfer sensor for diols.

Bispyridyl hydrogen bonding receptor 1 forms colored charge transfer (CT) complexes with complementary phenols and naphthols. Despite its low association constants of approximately 10(1) M(-1), receptor 1 was highly selective forming CT complexes of varying color and intensity with different diol guests. The selectivity of 1 was correlated with the ability of its CT band to simultaneously yield information about the association constant and the electronic structure of the phenols and naphthols.

The Kerf-Cut dressing: application of a woodworking technique for efficient postsurgical wound care.

Background: Simple surgical excision is one of the most common treatment methods in the dermatologist's armamentarium. We describe a precise postsurgical dressing technique that can be used for wound care of those patients whose treatment involves removal of lesions via cutaneous surgery.

Objective: To devise a novel, precise, and effective dressing technique for postsurgical wound care.

Structural and oxo-transfer reactivity differences of hexacoordinate and pentacoordinate (nitro)(tetraphenylporphinato)cobalt(III) derivatives.

The oxo-transfer catalyst (nitro)(pyridyl)cobalt(III) tetraphenylporphyrin has been reinvestigated by substitution of the distal pyridine ligand with 4-N,N-dimethylaminopyridine and 3,5-dichloropyridine. Differences in their structures and in the reactivity of the compounds toward catalytic secondary oxo transfer were investigated by FT-IR and UV-visible spectroscopy, cyclic voltammetry, X-ray diffraction, semiempirical calculations, and reactions with alkenes in dichloromethane solution. Very modest differences in the hexacoordinate compounds' structures were predicted and observed, but the secondary oxo-transfer reactivity at the nitro ligand varies markedly with the basicity of the pyridine ligand and the position of the coordination equilibrium.

Livedo reticularis: an underutilized diagnostic clue in cholesterol embolization syndrome.

Background: Cholesterol embolization syndrome (CES) is an increasingly recognized cause of acute renal insufficiency, which must be differentiated from other forms of systemic vasculitis by histologic examination of biopsies from involved organs. This report describes the optimal methods for detection and biopsy of areas of skin involved with livedo reticularis to confirm the diagnosis of CES.

Methods: This report describes 8 patients with unexplained acute renal insufficiency in whom the diagnosis of CES was suspected based on their clinical history.

Dermatomyositis with the features of inclusion body myositis associated with carcinoma of the bladder.

Inclusion body myositis (IBM) is a unique category of inflammatory myopathy. It is characterized histologically by the presence of muscle fibres with rimmed vacuoles and abnormal intracellular accumulations of proteins. We report here a 62-year-old patient with bladder carcinoma, where the signs of IBM overlapped with clinical features of dermatomyositis (DM).