Spermatogonial stem cells: unlimited potential.

Recent reports have demonstrated that adult cells can be reprogrammed to pluripotency, but mostly with genes delivered using retroviruses. Some of the genes are cancer causing; thus, these adult-derived embryonic stem (ES)-like cells cannot be used for therapy to cure human diseases. Remarkably, it has also been demonstrated recently by several groups that, in mice, spermatogonial stem cells (SSCs) can be reprogrammed to ES-like cells without the necessity of exogenously added genes. SSCs constitute one of the most important stem cell systems in the body, not only because they produce spermatozoa that transmit genetic information from generation to generation, but also because of the recent studies showing their remarkable plasticity. Very little is known about SSCs in humans, except for the earlier work of Clermont and colleagues who demonstrated that there are A(dark) and A(pale) spermatogonia, with the A(dark) referred to as the reserve stem cells and the A(pale) being the renewing stem cells. We now demonstrate that G protein-coupled receptor 125 (GPR125) may be a marker for human SSCs. Putative human SSCs can also be reprogrammed to pluripotency. We were able to achieve this result without the addition of genes, suggesting that human SSCs have considerable potential for cell-based, autologous organ regeneration therapy for various diseases.

Gastric outlet obstruction caused by a giant gastroduodenal artery aneurysm: a case report.

Gastric outlet (GO) obstruction in an adult is usually caused by intrinsic gastric or duodenal lesions or pancreatic tumours. This study describes a case of a 77-year-old man who developed GO obstruction due to extrinsic compression from a large gastroduodenal artery aneurysm under rupture. This cause of GO obstruction has never previously been reported in the literature.

Ascites associated with the initial presentation of Crohn's disease.

We report a case of a 23-yr-old patient who was initially admitted with severe Crohn's ileocolitis complicated by a large amount of exudative ascites. There was no evidence of malignancy, portal hypertension, or inflammation in any organ other than the bowel. We present the clinical course and response to treatment and discuss the possible mechanisms by which Crohn's disease might contribute to the development of exudative ascites.

Map integration at human chromosome 10: molecular and cytogenetic analysis of a chromosome-specific somatic cell hybrid panel and genomic clones, based on a well-supported genetic map.

Well-characterized, chromosome-specific somatic cell hybrid panels are powerful tools for the analysis of the human genome. We have characterized a panel of human x hamster somatic cell hybrids retaining fragments of human chromosome 10 by fluorescence in situ hybridization and associated them to genetic markers. Most of the hybrids were generated by the radiation-reduction method, starting from a chromosome 10-specific monochromosomal hybrid, whereas some were collected from hybrids retaining chromosome 10-specific fragments as a result of spontaneous in vitro rearrangements. PCR was used to score the retention of 57 microsatellite markers evenly distributed along a well-supported framework genetic map containing 149 loci uniquely placed at 69 anchor points (odds exceeding 1,000:1), with an average spacing of 2.8 cM. As an additional resource for genomic studies involving human chromosome 10, we report the cytogenetic localization of a series of YAC and PAC clones recognized by at least one genetic marker. Somatic cell hybrids provide a powerful source of partial chromosome paints useful for detailed clinical cytogenetic and primate chromosome evolution investigations. Furthermore, correlation of the above physical, genetic, and cytogenetic data contribute to an emerging consensus map of human chromosome 10.