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We describe the data reduction pipeline and control system for the RoboPol project. The RoboPol project is monitoring the optical R-band magnitude and linear polarization of a large sample of active galactic nuclei that is dominated by blazars. The pipeline calibrates and reduces each exposure frame, producing a measurement of the magnitude and linear polarization of every source in the 13 × 13 field of view. The control system combines a dynamic scheduler, realtime data reduction, and telescope automation to allow high-efficiency unassisted observations.

Tregs and NK cells may be important regulators of thyroid cancer progression.

Central issues in intracoronary infusion (ICI) of bone marrow (BM)-cells to damaged myocardium for improving cardiac function are the cell number that is feasible and safe to be administrated as well as the retention of cells in the target area. Our study addressed these issues in eight patients with chronic ischemic cardiomyopathy undergoing ICI of selected BM-progenitors. We could immunomagnetically isolate 0.8 +/- 0.32 x 10(7) CD133(+) cells and 0.75 +/- 0.24 x 10(7) CD133(-)CD34(+) cells from 310 +/- 40 ml BM. After labeling these cells with (99m)Tc-hexamethylpropylenamineoxime, they were infused into the infarct-related artery without any complication. Scintigraphic images 1 (eight patients) and 24 hours (four patients) after ICI revealed an uptake of 9.2% +/- 3.6 and 6.8% +/- 2.4 of the total infused radioactivity in the infarcted area of the heart, respectively; the remaining activity was distributed mainly to liver and spleen. We conclude that through ICI of CD133(+) and CD133(-)CD34(+) BM-progenitors a significant number of them are preferentially attracted to and retained in the chronic ischemic myocardium.

We present the design and performance of RoboPol, a four-channel optical polarimeter operating at the Skinakas Observatory in Crete, Greece. RoboPol is capable of measuring both relative linear Stokes parameters q and u (and the total intensity I) in one sky exposure. Though primarily used to measure the polarization of point sources in the R-band, the instrument features additional filters (B, V and I), enabling multi-wavelength imaging polarimetry over a large field of view (13.6 ′ × 13.6 ′ ). We demonstrate the accuracy and stability of the instrument throughout its five years of operation. Best performance is achieved within the central region of the field of view and in the R band. For such measurements the systematic uncertainty is below 0.1% in fractional linear polarization, p (0.05% maximum likelihood). Throughout all observing seasons the instrumental polarization varies within 0.1% in p and within ∼1 • in polarization angle.

CD3(-)CD16(-)CD56(bright) NK cell infiltration seems to be associated with PTC progression. These findings contribute to a better understanding of the immune response in PTC and may lead to novel immunotherapeutic approaches in these patients.

The 5-transmembrane receptor AC133 is expressed on a subpopulation of human hematopoietic cells that includes the CD34(bright) cells. We evaluated the developmental potential of AC133+CD34(bright) and AC133(dim/-)CD34+ cells isolated from 5 cord blood (CB) samples by studying the in vitro proliferative and differentiative potential of each population in both progenitor and mature cell expansion cultures. Seven-day culture of AC133+CD34(bright) cells with a cytokine combination favoring primitive progenitor cells causes a significant increase in CD34+, CFU-C and noncycling stem/progenitor cells HPP-Q (High Proliferative Potential-Quiescent), whereas culture of AC133(dim/-)CD34+ cells shows a limited increase in committed progenitor cells only. HPP-Q cells were not found in freshly isolated AC133(dim/-)CD34+ nor in expanded CD34+ cells derived from AC133(dim/-)CD34+ cells. No statistically significant difference was observed between the 1-week expanded AC133+ and the initial AC133+CD34(bright) cells regarding their clonogenic efficiency (CE), while expanded CD34+ cells derived from AC133(dim/-)CD34+ cells exhibited a decreased CE. Subexpansion of the reselected AC133+ derived from AC133+CD34(bright) cells reveals a further increase of stem/progenitor cells and the 14-day expanded AC133+ cells reveal an unchanged CE. Subexpansion of reselected 7-day CD34+ cells derived from AC133(dim/-)CD34+ cells was not possible. Culture of AC133+CD34(bright) cells in cytokines that favor megakaryopoiesis or erythropoiesis resulted in a significant expansion of CD41+ and CD71+ cells, respectively; AC133(dim/-)CD34+, in comparison, showed a limited potential to megakaryocytic differentiation and a decreased production of erythroid cells. Our data indicate that early high proliferating stem/progenitor cells and early committed progenitors are present in AC133+CD34(bright) cells, but not in AC133(dim/-)CD34+ cells; the latter represent late committed progenitors with limited proliferative potential.

The study of immunoglobulin heavy chain gene rearrangements in multiple myeloma has revealed extensive divergence from the germline sequences, but no intraclonal diversity with disease evolution. Our study investigated the state of the rearranged kappa light chain variable region (V kappa) gene segments as well as abortive V kappa family gene usage in cases of multiple myeloma expressing lambda light chain. We studied 11 cases of kappa and five cases of lambda light chain-expressing multiple myeloma. Total cellular RNA was extracted from the bone marrow of patients with overt disease and subjected to reverse transcription-polymerase chain reaction (RT-PCR) analysis to amplify clonally rearranged variable region sequences. Direct nucleotide sequencing by the dideoxy-chain termination method was performed on the RT-PCR products. We did not observe preferential usage of certain V kappa gene families. Mutation frequencies of the V kappa segments varied in number. In the majority of cases, extensive somatic mutations occurred within the complementarity determining regions (CDRs) of V kappa, whereas only a limited degree of divergence from the germline was observed in others. In all cases studied. replacement mutations tended to cluster in the CDRs, a finding compatible with an antigen-driven somatic hypermutation process. In 3/5 cases of lambda light-chain expressing multiple myeloma, abortively rearranged V kappa gene segments were amplified from genomic DNA; in two cases a non-templated nucleotide insertion rendering the V kappa sequences out-of-frame was observed, and in the third a stop codon was identified in the open reading frame of the V kappa sequence. Somatic mutations were observed in all cases of abortive V kappa genes studied; however, their distribution does not suggest selection by antigen. We conclude that somatic mutations observed in the V kappa regions of myeloma cells are of variable extent and suggest operation of the antigen selection process. Lack of or minimal somatic hypermutation in a few cases may be in some way implicated in the biological heterogeneity of the disease.