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Background aims. Pancreatic cancer, sometimes called a ‘silent killer’, is one of the most aggressive human malignancies, with a very poor prognosis. It is the fourth leading cause of cancer-related morbidity and mortality in the USA. Methods. A mouse peritoneal model was used to test the ability of unengineered rat umbilical cord matrix-derived stem cells (UCMSC) to control growth of pancreatic cancer. In vivo results were supported by various in vitro assays, such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), direct cell count, [3H]thymidine uptake and soft agar colony assays. Results. Co-culture of rat UCMSC with PAN02 murine pancreatic carcinoma cells (UCMSC:PAN02, 1:6 and 1:3) caused G0/G1 arrest and significantly attenuated the proliferation of PAN02 tumor cells, as monitored by MTT assay, direct cell counts and [3H]thymidine uptake assay. Rat UCMSC also significantly reduced PAN02 colony size and number, as measured by soft agar colony assay. The in vivo mouse studies showed that rat UCMSC treatment significantly decreased the peritoneal PAN02 tumor burden 3 weeks after tumor transplantation and increased mouse survival time. Histologic study revealed that intraperitoneally administered rat UCMSC survived for at least 3 weeks, and the majority were found near or inside the tumor. Conclusions. These results indicate that naive rat UCMSC alone remarkably attenuate the growth of pancreatic carcinoma cells in vitro and in a mouse peritoneal model. This implies that UCMSC could be a potential tool for targeted cytotherapy for pancreatic cancer. [ABSTRACT FROM AUTHOR]

Al2SiO5 reaction textures in aluminous schist and quartzite of the northern Picuris range, north-central New Mexico, record a paragenetic sequence of kyanite to sillimanite to andalusite, consistent with a clockwise P–T loop, with minor decompression near the Al2SiO5 triple-point. Peak metamorphic temperatures are estimated at 510–525°C, at 4·0–4·2 kbar. Kyanite and fibrolite are strongly deformed; some prismatic sillimanite, and all andalusite are relatively undeformed. Monazite occurs as inclusions within kyanite, mats of sillimanite and centimetre-scale porphyroblasts of andalusite, and is typically aligned subparallel to the dominant regional foliation (S0/S1 or S2) and extension lineation (L1). Back-scatter electron images and X-ray maps of monazite reveal distinct core, intermediate and rim compositional domains. Monazite–xenotime thermometry from the intermediate and rim domains yields temperatures of 405–470°C (±50°C) and 500–520°C (±50°C), respectively, consistent with the prograde to peak metamorphic growth of monazite. In situ, ion microprobe analyses from five monazites yield an upper intercept age of 1417 ± 9 Ma. Near-concordant to concordant analyses yield 207Pb–206Pb ages from 1434 ± 12 Ma (core) to 1390 ± 20 Ma (rim). We find no evidence of older regional metamorphism related to the ∼1650 Ma Mazatzal Orogeny. [ABSTRACT FROM AUTHOR]