UT2 Practical Applications of the Health Utilities Index

The Health Utilities Index is designed to describe and to quantify the health status and the health-related quality-of-life (HRQOL) of subjects. This validated and reliable instrument has been employed by over 100 research groups worldwide and exists in three formats (face-to-face interview, telephone interview and self-administration). Translations into several languages are also available. As a generic preference-weighted system, the Health Utilities Index not only measures and describes health status, but also provides a quantitative measure of HRQOL as a single summary score based on community preferences for health status. The score, founded on utility theory and anchored to the conventional 0–1 (dead–healthy) scale, is appropriate as a quality-weight in the calculation of quality-adjusted life-years (QALY's). Given that QALYs have been recognized as a universal measure for use in cost-effectiveness/cost-utility analyses and are recommended in the reporting and monitoring of population health, this instrument has wide ranging applications in outcomes and health economic research. This workshop will provide an introduction to the Health Utilities Index and focus on its practical application. We will describe our experiences as they relate to issues such as frequency and mode of administration, patient recall, compliance, sample size considerations, data analysis and interpretation. Citing previous studies, this workshop will demonstrate how the Health Utilities Index can be utilized in prospective clinical research, patient surveys and as a means for developing utility estimates in retrospective health economic models. Researchers and analysts involved in quality-of-life and health economic evaluations will gain a working knowledge of the Health Utilities Index and an appreciation of its diversified use as a generic HRQOL instruments.     

Simultaneous complementary idiotypic responses: absence of reciprocal regulation

Complementary antibodies, i.e. antibodies having combining site structures which are at least partially directed against each other, were induced in A/He mice by immunization with phosphorylcholine (Pc) coupled to keyhole limpet hemocyanin or with the Pc-binding IgA myeloma protein, HOPC-8 (H8). Both responses were monitored by enumerating plaque-forming cells and assaying serum antibody levels to Pc and H8. Prior immunization with H8 markedly suppressed subsequent immunization with Pc and vice versa; neither plaque-forming cell response was diminished, however, when mice were immunized simultaneously with Pc and H8. Experiments were designed to determine if the absence of reciprocal regulation was due to change in idiotypes. This was determined by measuring inhibition of plaque formation using complementary antibody. Plaque formation by cells was equally inhibited by high dilutions of the appropriate complementary antibody whether cells were from mice immunized with one, the other, or both antigens. Thus, the absence of regulation could not be accounted for by emergence of different idiotypes. Interestingly, sera from mice immunized to have high responses to both antigens were relatively ineffective in inhibiting plaque formation or suppressing immunization to Pc. However, such sera contained complexes of the complementary antibodies; apparently antibody to Pc in such sera quenches or neutralizes the activity of anti-H8 antibody. But the formation of complexes, at least measurable levels of circulating complexes, must be a result rather than the cause for the absence of reciprocal regulation, since regulation was also absent when immunization to Pc was manipulated so that responses were too low to result in detectable levels of circulating antibody to Pc. It is proposed that simultaneous complementary responses may occur in nature to other antigens and antibodies, and that such simultaneous responses may cause pathologic changes.     

间歇性红外线加热对人成纤维细胞三维立体培养的影响

目的　观察红外线加热对人成纤维细胞三维立体培养的影响。方法　在人成纤维三维立体培养模型基础上 ,用红外线加热装置间歇性加热 ,共设 42℃组 (A组 )、3 8℃组 (B组 )和 3 3℃组对照组 (C组 ) ,观察第 0、2、3、5和 7d凝胶收缩状况及纤维细胞计数。结果　第 3天 ,A组的胶原凝胶收缩 (5 4.7% )明显大于B组 (4 8.5 % )和C组 (3 4.8% ) (P <0 .0 0 1)。第 7天 ,A、B、C三组的胶原凝胶收缩分别为 67%、5 5 .8%和49 .47% (P <0 .0 0 1) ,同时发现 ,各组间成纤维细胞生长状况与胶原凝胶收缩呈正相关关系。结论　间歇性红外线加热可通过促进成纤维细胞增殖而使胶原凝胶收缩 ,对慢性伤口的愈合可能有促进作用     

Evaluation of a centrifugal blood cell processor for washing platelet concentrates

A semiautomated saline wash procedure using a blood cell processor was evaluated as a technique for removing plasma from platelet concentrates. In vitro studies demonstrated 92 to 99.6 percent (mean, 96%) removal of total plasma protein (n = 30) with 84 to 97 percent (mean, 90.8%) platelet recovery (n = 28) in post-wash units. Post-wash pH values changed by +0.2 to -0.86 (mean, -0.47) (n = 30); the level of recovery from hypotonic shock was 69 to 97 percent (mean, 86%) (n = 11) of pre-wash units; weighted morphology scores decreased from a mean of 248 to 223 (n = 9). Aggregation response to arachidonic acid, collagen, and adenosine diphosphate plus epinephrine showed essentially no change following the wash procedure, and electron microscopy demonstrated slight morphologic alteration. Autologous platelets labeled with indium-111 demonstrated 43 +/- 20 percent recovery (n = 11) for washed units, compared to 41 +/- 10 percent for control unwashed units (n = 5); mean survivals were 140 +/- 41 hours (n = 11) for washed platelets and 185 +/- 28 hours for unwashed units (n = 5). Thirteen alloimmunized patients receiving 55 washed platelet concentrates demonstrated a mean 1- to 4-hour corrected count increment of 3.99 X 10(3) per microliter, compared to 3.02 X 10(3) per microliter for 77 unwashed platelet units given to the same patients. This study documents that platelet concentrates maintain viability and efficacy following a semiautomated saline wash method using the Cobe 2991 Blood Cell Processor, a technique that may be helpful for patients who require plasma-depleted platelet transfusions.