Synthesis and crystal structure of 2,4,6,8-tetra-kis-(3,5-di--butyl-phen-oxy)pyrimido[5,4-]pyrimidine: expansion of the Piedfort concept.

The title host compound, CHNO, designed to self-assemble to form a new type of extended core Piedfort unit reminiscent of an eight-legged spider host, forms a number of crystalline inclusion compounds favouring oxygen-containing guest mol-ecules. We have established the presence of this unit in the unsolvated mol-ecular crystal at 100 K, which is monoclinic, space group 2/, with = 8. The new Piedfort unit is chiral and its core structure closely approximates to symmetry, with both enanti-omers present in the crystal.

The first members of the octasubstituted naphthalene spider-host series with type I (abababab) conformation: gateway to new nano-host gas storage materials.

Octakis(m-tolyloxymethyl)naphthalene, the first Type I spider host produced, crystallises from tetraglyme forming a novel channel structure with the host molecule attaining exact D(2) symmetry. The (flexible) channel structure is retained for guest CS(2), the host now only having exact C(2) symmetry. The octa-sulfone octakis(m-tolylsulfonylmethyl)naphthalene is also of Type I in its triclinic DMSO clathrate.

Acrokeratosis verruciformis of Hopf is caused by mutation in ATP2A2: evidence that it is allelic to Darier's disease.

Acrokeratosis verruciformis of Hopf is a localized disorder of keratinization affecting the distal extremities. Onset is early in life and the disease is inherited in an autosomal dominant fashion. Although histology of acrokeratosis verruciformis lesions shows no evidence of dyskeratosis, a possible relationship with Darier's disease has long been postulated on the basis of clinical similarity.

Non-alcoholic steatohepatitis: a common cause of progressive chronic liver injury?

Aim: To investigate the natural history of patients with non-alcoholic steatohepatitis by means of a prospective histological study.

Methods: One thousand five hundred and seventy one patients underwent liver biopsy at the Western Infirmary in Glasgow during the 10 year period 1985 to 1994. All biopsies were reported by a single pathologist: 62 were confirmed as having non-alcoholic steatohepatitis and prospective follow up was conducted in 1999.