We used stable isotope analyses to evaluate body size-dependent trophic and habitat shifts in krill during the austral summer around the South Shetland Islands, Antarctica. We found evidence SB273005 for an asymmetric, ontogenetic niche expansion with adults of both sexes having higher and more variable delta N-15 values but consistent delta C-13 values in comparison with juveniles. This result suggests that while phytoplankton likely remains an important life-long resource, krill in our study area expand their dietary niche to include higher trophic food sources as body size increases. The broader dietary niches observed in adults may help buffer them from recent climate-driven shifts in phytoplankton communities that
negatively affect larval or juvenile krill that rely predominately
on autotrophic resources.”
“To investigate the differences between the effects of mesenchymal stem cells (MSCs) administered in the early and late phases of tumorigenesis, MSCs were isolated from bone marrow and colorectal tumors were produced by exposing 7-week-old F344 rats to 1,2-dimethylhydrazine and dextran sulfate sodium. We evaluated tumor number and volume (week 25), MSC localization, number of aberrant crypt foci (ACF), transforming growth factor (TGF)-beta 1 protein levels in the rectum after DNA Synthesis inhibitor administration of MSCs (week 5 or 15), and the effects of MSC-conditioned medium on ACL15 cell proliferation. Administered MSCs labeled with PKH26 were observed in the rectum. Administered MSCs in the early phase (week 5) before tumor selleck inhibitor occurrence (week 12) significantly decreased tumor number and volume (1.5 vs 4 and 21 mm(3) vs 170 mm(3); p smaller than 0.01), but not administered MSCs in the late phase (week 15). Administered MSCs in the early phase reduced
ACF number on days 14 and 35 (1.9 vs 4.1 and 3.7 vs 7.3; p smaller than 0.01). Rectal TGF-beta 1 increased 1.3 fold on day 3, and MSC-conditioned medium containing TGF-beta 1 abundantly inhibited ACL15 cell proliferation. MSCs administered in the early phase but not late phase inhibited colorectal tumor development in a rat model.”
“Background. YKL-40 association with human disease has been the object of many years of investigation. beta-thalassemia patients are affected by hepatic siderosis, which determines a fibrotic process and tissue remodelling. Chitotriosidase has been found to be increased in thalassemic patients returning to normal in patients submitted to bone marrow transplantation. YKL-40 is associated with macrophage activation in liver and in other tissues. The aim of the study was to analyse the level of serum YKL-40 and plasma chitotriosidase activity of patients with beta-thalassemia to assess whether their expression correlates with liver disease and degree of liver siderosis. Methods. Expression of YKL-40 and chitotriosidase as a marker of inflammation in 69 thalassemic patients were evaluated.