Clinical Research Risk Assessment Among Individuals With Mild Cognitive Impairment

OBJECTIVE:: To determine whether individuals with mild cognitive impairment (MCI) differ from cognitively normal (NC) elders on a risk assessment task and whether participants and their study partners evaluate risk and benefit similarly. DESIGN:: Cross-sectional. SETTING:: University medical setting. PARTICIPANTS:: Seventy-nine participants (NC, n = 40; MCI, n = 39), age 60-90 years (73 ± 7 years; 53% women), and 64 study partners (NC, n = 36; MCI, n = 28), age 38-84 years (68 ± 10 years; 67% women). MEASUREMENTS:: Participants and study partners completed a risk assessment task that involved ranking from least to most risk four hypothetical vignettes for memory loss research (brain autopsy, blood draw, oral medication, neurosurgery). Participants also completed decisional capacity for research and neuropsychological protocols. RESULTS:: MCI participants' risk rankings differed from NC risk rankings (p <0.001) with MCI participants ranking brain autopsy higher and an oral medication trial lower. Demographic, decisional capacity, and neuropsychological variables could not explain MCI participant performances. Participants and their study partners had comparable risk assessment performance (p = 1.0). MCI study partners performed similar to their MCI participant counterparts but were different from NC study partners (p = 0.002; i.e., ranking autopsy higher and oral medication lower). CONCLUSION:: Findings suggest that individuals with MCI assess risk differently than NC peers by overestimating the risk (or underestimating the benefit) of brain autopsy and underestimating the risk (or overestimating the benefit) of oral medication. Study partners display a similar pattern. These observations may be secondary to MCI participants' (and their study partners') personal connection to the potential benefits of an experimental medication for memory loss.     

The evaluation of gastrointestinal function in diabetic patients

Ｎｏｗａｄａｙｓ,ａｎｕｍｂｅｒｏｆｏｐｔｉｏｎｓａｒｅａｖａｉｌａｂｌｅｆｏｒｔｈｅａｓｅｓｍｅｎｔｏｆｇａｓｔｒｉｃｍｏｔｏｒｆｕｎｃｔｉｏｎ．Ｔｈｕｓ,ａｇｌｏｂａｌｅｖａｌｕａｔｉｏｎｏｆｇａｓｔｒｉｃｍｏｔｏｒｆｕｎｃｔｉｏｎｍａｙｂｅｏｂ...     

Expression of CD27 and its ligand, CD70, on chronic lymphocytic leukemia B cells

Crosslinking the CD27 antigen on T cells provides a costimulatory signal that, in concert with T-cell receptor crosslinking, can induce T- cell proliferation and cellular immune activation. We find that chronic lymphocytic leukemia (CLL) B cells from most patients coexpress both membrane-bound and soluble CD27, along with its newly identified ligand, CD70. The expression of soluble CD27 may preclude leukemic B cells from stimulating T cells via CD70, thereby potentially impairing their ability to function as effective antigen-presenting cells. We find that leukemic B-cell expression of soluble and membrane-bound CD27 can be downmodulated through a CD40-dependent signal. This signal also induces enhanced expression of CD70 on both normal and leukemic B cells. We find that tumor necrosis factor (TNF)-alpha, or the Th1 cytokine interferon (IFN)-gamma, also can induce downmodulation of CD27, whereas Th2-associated cytokines interleukin-4 (IL-4) or IL-10 can enhance leukemic B-cell expression of this accessory molecule. The modulation of CD27 induced by these conditions is accompanied by reciprocal changes in the expression levels of CD70, suggesting that these accessory molecules may be engaged in reciprocal receptor-ligand downmodulation. Consistent with this, we observe that co-culture of CLL B cells with transfected murine plasmacytoma cells that express human CD70 affects downmodulation of CD27 and enhanced expression of CD70 on leukemic B cells, but does not affect expression of CD27 mRNA. However, we find that CD40-crosslinking, in addition to reducing the level of CD27 protein, also reduces leukemic B-cell expression of CD27 mRNA. This argues that the changes in the expression levels of CD27 following CD40-signaling are not simply due to induced increases in the expression levels of CD70. Finally, we demonstrate that reciprocal changes in expression of CD27 and CD70 may contribute to the enhanced antigen-presenting capacity of CLL B cells after CD40-dependent leukemic B-cell activation. These findings expand the understanding of the regulation of costimulatory molecules important in antigen presentation and also have implications for the immunobiology of and therapy for CLL.