Isolation of Chlamydia psittaci from avian sources using growth in cell culture

A method is described for the isolation of Chlamydia psittaci using cell culture treated with 5-iodo-2-deoxyuridine, and subsequent identification by direct fluorescent antibody staining. The method was applied to 110 sets of tissues from a variety of avian specimens submitted for diagnosis. Chlamydiae were isolated and identified in 24 specimens: 13 from parrots, 7 from turkeys and 4 from pigeons.     

DO HEALTH BOOKLETS ADD ANYTHING TO PROFESSIONAL GUIDANCE? AN EVALUATION STUDY

An outcome evaluation was undertaken of a booklet used as a supplement to nurses' guidance to mothers on the introduction of solids to infants. The study was based on a classical before and after design, including a control group. Measures were taken of knowledge, practice and preferred learning mode. Gains in knowledge and practice were significantly greater for the experimental group. Reductions in knowledge scores, where they were expected to increase, are discussed and a set of conditions thought to govern the effectiveness of health messages is offered. Despite prolonged use of pamphlets, posters, leaflets and booklets in public education few outcome evaluations of such educational aids have been published. The face validity of these aids is a powerful incentive for their continued use; furthermore, outcome evaluations are usually complex and expensive. In this study a booklet called A Solid Start (dealing with the introduction of solid foods to imports) was chosen because —

• (a) the booklet was typical in style of many publications;
• (b) the topic of infant feeding ensured a ready supply of experimental subjects;
• (c) it was prepared in response to expressed needs (16 experienced nurses were asked what booklets mothers requested).
• (d) it was well developed, competently written and subjected to process evaluations before reaching its final stage;
• (e) it was a new booklet, not distributed previously;
• (f) it dealt with a brief time period in child development.

     

Biosynthesis and intracellular transport of MHC class II molecules associated with a mutated, glycosaminoglycan-negative invariant chain

The MHC Class II molecular complex is composed of polymorphic alpha and beta chains and a non-polymorphic "invariant" chain (Ii) that can be converted to a chondroitin sulfate proteoglycan. To determine whether the proteoglycan form of invariant chain (Ii-CS) had a role in the expression of the Class II complex, we studied the biosynthetic fate of alpha-beta in cells transfected either with normal Ii cDNA or with a site-directed mutant of Ii (IiAla201) that lacked the site of glycosaminoglycan addition. We had reported [Miller J., Hatch J. A., Simonis S. and Cullen S. E. (1988) Proc. Natl. Acad. Sci. U.S.A. 85, 1359-1363] that the mutant protein associated stably with alpha and beta chains, and that it showed charge heterogeneity suggesting some oligosaccharide processing. In this study we demonstrated that the rate and extent of alpha-beta processing and the rate of alpha-beta cell surface expression is the same in the presence of either normal or mutant Ii. Examination of the mutant Ii protein itself revealed normal transport through different processing compartments, as evidenced by the addition of fatty acid and by maturation of N-linked oligosaccharides. Moreover, though the rate of conversion of IiAla201 into more processed forms was slower in the absence of alpha-beta than in its presence, this was also typical of the wild type invariant chain. The ability to alter glycosaminoglycan addition without significantly disturbing other processing events or trafficking should allow a rigorous assessment of the impact of glycosaminoglycan addition on Class II function.     

Histopathological features of congenital fundus lesions in familial adenomatous polyposis

We report the light and electron microscopic findings for two lesions from two patients who died of complications of familial adenomatous polyposis. In the first case microscopy of a small (100 to 200 mu), uniformly dark lesion (the commonest type seen in this condition) showed enlarged retinal pigment epithelial cells with an increased number of pigment granules. This is consistent with the term "hypertrophy of the retinal pigment epithelium", currently used to describe these lesions. In the second case we sectioned a larger (1000 to 1500 mu), oval, grey lesion from the posterior pole. The pigment epithelium was normal, but between it and outer retina was an unusual choristoma consisting largely of myelinated axons and astrocytes.