A significant improvement in fluorescence in situ hybridization, enabling the detection of single-copy genes as small as 500 bp directly on banded chromosomes, is presented. The induction of chromosome banding, which does not require additional handling or any system of amplification, is obtained simply by using an alkaline (pH 11) p-phenylenediamine anti-fade solution. As the banding produced is related to the timing of 5-bromodeoxyuridine incorporation, either R- or G-banding, constitutive heterochromatin staining, or chromosome asymmetry can be observed simultaneously with the fluorescent hybridized spots. Results of hybridization of small cDNA probes for the human genes for motilin, thymidylate synthetase, and lymphocyte activation-3 are provided as examples of the high-resolution mapping obtainable with this technique.

Isodicentric chromosomes are the most commonly reported aberrations of the human Y chromosome. As they are unstable during cell division and can generate various types of cell lines, most reported patients are chromosomal mosaics, generally including a 45,X cell line. Phenotypes depend on the location of the breakpoints as well as on the proportion of each cell line and vary from male to abnormal female or individual with ambiguous genitalia. Although phenotypic variability is known to also depend on the degree of mosaicism in the various tissues, gonads are rarely studied. We report nine cases of isodicentric Y chromosomes studied by conventional and molecular cytogenetic: three males, five females, and one individual with sexual ambiguity. Two males had a non-mosaic karyotype, while the third male was a mosaic with a predominant 46,XY cell line. Three of the females had a major 45,X cell line, while the last two females and the patient with ambiguous genitalia had a major 46,X,idic(Y) cell line. Analyses of gonadal tissues from the individual with sexual ambiguity and of three of the five female patients gave results concordant with their phenotype, allowing us to better understand the sexual differentiation of these patients.

A significant number of women with IBD do not breastfeed their children. Any relationship between breastfeeding and disease activity may be more a consequence of discontinuation of IBD therapies.

We sought to prospectively evaluate the clinical application of the American College of Cardiology Foundation/American Society of Echocardiography Appropriateness Criteria (AC) for transthoracic echocardiography in a single-center university hospital. Indications for transthoracic echocardiograms (TTE) were prospectively determined for consecutive studies by 2 reviewers and categorized, according to the AC for TTE, as appropriate (A) or inappropriate (I). The overall level of agreement in characterizing appropriateness between reviewers was high (kappa ϭ 0.83). Among the 1,553 studies for which a primary indication was determined, 89% were covered in the AC for TTE. Of these studies, 89% were A, and 11% were I. New important TTE abnormalities were more common on A compared with I studies (40% vs. 17%, p Ͻ 0.001), and noncardiac specialists more frequently ordered I studies (13% vs. 9%, p ϭ 0.04). In conclusion, the AC for TTE encompasses the majority of clinical indications for TTE and appears to reasonably stratify TTE ordering. However, revisions will be needed to fully capture and stratify appropriate clinical practice.