No abstract

Cell separation from peripheral blood was investigated using surface-modified polyurethane (PU) membranes with different functional groups. Both red blood cells and platelets could pass through unmodified PU and PU-SO 3 H membranes, whereas the red blood cells preferentially passed through PU-N(C 2 H 5 ) 2 and PU-NHC 2 H 4 OH membranes. The permeation ratio of T and B cells was Ͻ25% for the surface-modified and unmodified PU membranes. CD34 ϩ cells have been recognized as various kinds of stem cells including hematopoietic and mesenchymal stem cells. The adhesiveness of CD34 ϩ cells on the PU membranes was found to be higher than that of red blood cells, platelets, T cells, or B cells. Overall, the adhesiveness of blood cells on the PU membranes increased in the following order: red blood cells Յ platelets Ͻ T cells Յ B cells Ͻ CD34 ϩ cells. Treatment of PU-COOH membranes with a human albumin solution to detach adhered blood cells, allowed recovery of mainly CD34 ϩ cells in the permeate, whereas both red blood cells and platelets could be isolated in the permeate using unmodified PU membranes. The PU membranes showed different permeation and recovery ratios of specific cells depending on the functional groups attached to the membranes.

This exploratory study focused on the role of risk and protective factors in 179 adolescents from a middle and lower income northeastern school district. The protective factors examined were family cohesion, locus of control, mother/father communication, and relationship with a nonparent adult. The study found that the protective factors were powerful predictors of adaptation in their own right independent of risk. Protective factors were found to be highly context specific and there was no evidence of broadly applicable protective factors. Gender was found to be an important aspect of context, and there were significant sex differences. Most strikingly, the study did not find any significant interactions between protective factors and risk for girls or boys. Thus, these results support the growing view that researchers must identify specific rather than global protective factors that provide protection in the space of specific risks for youth in specific life contexts.

Cell separation from peripheral blood was investigated using polyurethane (PU) foaming membranes and PU membranes (pore size, 5 or 12 mum) at different blood permeation speeds. Permeation ratio of hematopoietic stem cells (CD34(+) cells) through the PU membranes was the lowest among the blood cells at any blood permeation speed. This is thought to be because CD34(+) cells are more adhesive than red blood cells (RBCs), platelets, T cells, and B cells. Primitive hematopoietic stem and progenitor cells tend to adhere to the surface of mature blood cells, because of the high expression of cell-adhesion molecules on the surface of the cells. Human serum albumin solution was exposed to PU-COOH membranes to detach adhered cells from the surface of the membranes, allowing isolation of CD34(+) cells and reduction of RBCs in the permeate solution. Most purified CD34(+) cells (high recovery ratio of CD34(+) cells divided by recovery ratio of RBCs) were obtained in the recovery process using PU-COOH membranes (pore size, 5.2 microm) at a permeation speed of 0.3-1 mL/min.

We have utilized color Doppler ultrasonography (CDU) to evaluate the thyroid blood flow area (TBFA) quantitatively, and we propose criteria to differentiate Graves' disease (GD) and destruction-induced thyrotoxicosis (DT) in patients with thyrotoxicosis. We studied 32 patients with diffuse toxic goiter, 21 with GD in the euthyroid state, 12 with chronic thyroiditis in the euthyroid state, and 31 normal individuals. TBFA was calculated as (thyroid blood flow area/thyroid area) x 100%. CDU showed high sensitivity (84%) and specificity (90%) in distinguishing GD from DT when TBFA was between 7.7% and 8.8%. Using CDU to diagnose GD in cases with TBFA >or=8% or positive serum anti-thyrotropin receptor antibody (TRAb), the sensitivity was 95% and the specificity was 90%, which are similar results to those obtained when GD was diagnosed by radioactive iodine uptake (sensitivity 100%, specificity 90%). Therefore, CDU is a more useful and economical method of distinguishing GD patients with TBFA of 8% or above from DT than measurement of TRAb or radioactive iodine uptake.