Echocardiographic-determined septal morphology in Z-disc hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) can be classified into at least four major anatomic subsets based upon the septal contour, and the location and extent of hypertrophy: reverse curvature-, sigmoidal-, apical-, and neutral contour-HCM. Here, we sought to identify genetic determinants for sigmoidal-HCM and hypothesized that Z-disc-HCM may be associated preferentially with a sigmoidal phenotype. Utilizing PCR, DHPLC, and direct DNA sequencing, we performed mutational analysis of five genes encoding cardiomyopathy-associated Z-disc proteins.

HuR mRNA ligands expressed after seizure.

HuR is a ubiquitously expressed AU-rich element (ARE)-binding protein that interacts with and stabilizes selective early response gene (ERG) mRNAs after cell activation or stress. To date, approximately 20 mRNAs have been unambiguously defined as HuR ligands. Given the discordance between the large number of ERG mRNAs and those few defined as ligands, we applied in vitro selection to isolate a broad range of HuR mRNA ligands using postseizure mouse hippocampal tissue.

RhoB mRNA is stabilized by HuR after UV light.

RhoB is a small GTP-binding protein that is involved in apoptotic signal transduction. We have cloned the mouse RhoB mRNA including a 1377 nucleotide 3'-untranslated region (UTR) that contains six AU-rich elements (AREs) as well as several uridine-rich stretches. There is 94% homology overall between the mouse and rat RhoB genes and 92% homology between the mouse and a putative human clone.

Automated quantitative analysis of the shift of frequency spectra generated by attenuated signals from contrast microbubbles.

The ultrasound-induced harmonic microbubble response spectrum is known to shift to lower frequencies with increasing tissue attenuation. We hypothesized that this shift could be reproducibly detected in received broadband radiofrequency spectra. We used an automatic Gaussian curve-fitting technique to measure the mean harmonic response generated by three different contrast agents at six incremental levels of attenuation.