Desymmetrization of Diols by Phosphorylation with a Titanium-BINOLate Catalyst.

The desymmetrization of ten prochiral diols by phosphoryl transfer with a titanium-BINOLate complex is discussed. The phosphorylation of nine 1,3-propane diols is achieved in yields of 50-98%. Enantiomeric ratios as high as 92:8 are achieved with diols containing a quaternary C-2 center incorporating a protected amine.

Pancreatoblastoma: a rare tumor still evolving in clinical presentation and histology.

Context: Pancreatoblastoma is a rare neoplasm in adults with a total of only 24 cases that have been reported in the literature. Adult pancreatoblastomas are large tumors and majority are larger than 8 cm at the time of diagnosis. Metastasis is seen in 26% of adults and usually involves the liver and then the lymph nodes.

Urothelial metaplasia of the seminal vesicles: a report of 2 cases.

Although urothelial metaplasia has been reported in the fallopian tube, urothelium in the seminal vesicle has been rarely reported. We report 2 cases of urothelial epithelium in seminal vesicles from radical prostatectomy specimens. One case involved a 63-year-old patient with pT2c prostatic adenocarcinoma (Gleason pattern 3+4; total score, 7).

Cell-permeable MR contrast agents with increased intracellular retention.

Magnetic resonance imaging (MRI) is a technique used in both clinical and experimental settings to produce high-resolution images of opaque organisms without ionizing radiation. Currently, MR imaging is augmented by contrast agents, and the vast majority these small molecule Gd(III) chelates are confined to the extracellular regions. As a result, contrast agents are confined to vascular regions reducing their ability to provide information about cell physiology or molecular pathology.

DNA-TiO2 nanoconjugates labeled with magnetic resonance contrast agents.

Recent efforts have shown that nanoscale materials, specifically, metal-based nanoparticles, hold particular promise for the development of multifunctional imaging probes. These new materials provide the means to chaperone and concentrate both drugs and contrast agents in specific organs, tissues, and cells. Therefore, we have prepared a Gd(III)-modified DNA-TiO2 semiconducting nanoparticle that is detectable in cells by MR imaging.

Quantitative imaging of cell-permeable magnetic resonance contrast agents using x-ray fluorescence.

The inability to transduce cellular membranes is a limitation of current magnetic resonance imaging probes used in biologic and clinical settings. This constraint confines contrast agents to extracellular and vascular regions of the body, drastically reducing their viability for investigating processes and cycles in developmental biology. Conversely, a contrast agent with the ability to permeate cell membranes could be used in visualizing cell patterning, cell fate mapping, gene therapy, and, eventually, noninvasive cancer diagnosis.