An economical and practical method for whole-mount in situ hybridization for mouse embryos and organs.

Whole-mount in situ hybridization (WISH) is a useful method for detecting specific gene expression patterns at their site of action during embryonic development. Traditional WISH methods are costly and suitable only for mouse embryos younger than 11.5 days. We present here an economical and practical in situ hybridization method using DIG-labeled RNA probes. We changed the conditions in several steps to make the WISH method suitable for whole mouse embryos from embryonic days 9.5 to 12.5 and for older stage mouse embryonic organs. We performed all steps in one microcentrifuge tube up to the staining steps to avoid losing or damaging the mouse embryos. We re-used the solutions and materials to make the method more economical and suitable for less sophisticated laboratories. We also performed ß-galactosidase staining on Tb × 18 Cre/Rosa26/LacZ mouse embryos; the results agreed with the in situ hybridization results. Finally, we sectioned the specimens after hybridization and ß-galactosidase staining; the results agreed with the literature.

Susceptibility-weighted imaging in patients with pyogenic brain abscesses at 1.5T: characteristics of the abscess capsule.

BACKGROUND AND PURPOSE: SWI is a high-resolution 3D, fully velocity-compensated gradient-echo sequence that uses both magnitude and phase data. The purpose of this study was to investigate the phase behavior of the capsule of pyogenic brain abscesses with noncontrast SWI. MATERIALS AND METHODS: Fourteen patients with pyogenic brain abscesses were studied at 1.5T. In all of the patients, SWI images were obtained and reviewed in addition to conventional MR images. Phase values within the abscess capsule were measured and compared with those from the abscess cavities and contralateral normal white matter using 1-way repeated measures ANOVA with post hoc Bonferroni analysis. RESULTS: SWI phase images showed mild hypointesity in 6 patients, isointensity in 3 patients, and mixed iso- to mild hypointensity in 5 patients. The means of phase in the cavity, rim of abscesses, and contralateral normal white matter were -7.552 × 10(-3) ± 0.024, -0.105 ± 0.080, and +0.029 ± 0.011 radians, respectively. Post hoc comparisons showed significant differences between any pair of the 3 regions (abscess cavity, rim capsule, and normal white matter) in SWI (all Ps < .005). CONCLUSIONS: SWI phase imaging shows evidence of paramagnetic substances in agreement with the presence of free radicals from phagocytosis. SWI may provide additional information valuable in the characterization of pyogenic brain abscesses.

Evaluation of an Intracranial Arteriovenous Malformation by Multi-Detector CT Angiography. A Case Report.

Intracranial arteriovenous malformations are congenital vascular lesions characterized by localized arteriovenous shunting. Digital subtraction angiography is the gold standard for diagnosis. We herein report a case of intracranial arteriovenous malformations diagnosed by multi-detector computed tomographic (MDCT) angiography. The findings of MDCT angiography were confirmed by digital subtraction angiography. CT angiography might be a useful first-line screening tool, especially in an emergency situation.

Multidetector CT angiography in diagnosing type I and type IVA spinal vascular malformations.

Multidetector CT (MDCT) angiography is an imaging technique that can provide high-resolution and high-contrast images; however, published reports of MDCT angiography in the evaluation of spinal vascular malformations are limited. We present 2 cases in which MDCT angiography led to diagnosis of a type I (spinal dural arteriovenous fistula) in one and type IVA (perimedullary spinal cord simple arteriovenous fistula fed by a single arterial feeder) spinal vascular malformation, both confirmed by conventional angiography. MDCT angiography can localize the feeding vessel and the fistula, thus greatly reducing the amount of time required for conventional angiography.