Supplementary Material for: Effects of Ultrapure Hemodialysis and Low Molecular Weight Heparin on the Endothelial Surface Layer

<b><i>Background:</i></b> Chronic kidney disease patients show changes in the endothelial surface layer (ESL). Whether hemodialysis (HD) itself or low molecular weight heparins (LMWH) induce ESL alterations is unknown. <b><i>Methods:</i></b> We studied the ESL in 20 HD patients with Sidestream Dark Field Imaging [measuring perfused boundary region (PBR)] and measurement of ESL constituents in plasma during HD in 2 studies. LMWH was administered at the start of HD in study A, and 120 min after the start of HD in study B. Mean platelet volume (MPV) and platelet large cell ratio (P-LCR) were also measured. <b><i>Results:</i></b> Syndecan-1 increased significantly 30 min after LMWH administration. sP-Selectin increased 120 min after HD start, and MPV and P-LCR decreased significantly during HD. No significant changes of PBR, sE-Selectin, sICAM-1, or sVCAM-1 were perceived. <b><i>Conclusions:</i></b> HD caused a significant increase in Syndecan-1 without a change in PBR. The administration of LMWH appeared to precede the rise in Syndecan-1.

**背景：** 慢性肾脏病患者的内皮表面层（endothelial surface layer, ESL）会发生病理性改变。目前尚不明确血液透析（hemodialysis, HD）本身，或是低分子肝素（low molecular weight heparins, LMWH）是否会诱导ESL发生改变。
**方法：** 本研究通过两项实验，采用侧流暗场成像（Sidestream Dark Field Imaging）技术对20名血液透析患者的内皮表面层进行研究，该技术可检测灌注边界区（perfused boundary region, PBR），并在血液透析过程中对血浆中的内皮表面层相关成分进行定量检测。实验A中，低分子肝素于血液透析开始时给药；实验B中，低分子肝素于血液透析开始后120分钟给药。此外，本研究同时检测了平均血小板体积（mean platelet volume, MPV）与血小板大细胞比率（platelet large cell ratio, P-LCR）。
**结果：** 给予低分子肝素30分钟后，多配体聚糖-1（Syndecan-1）水平显著升高。血液透析开始120分钟后，可溶性P-选择素（sP-Selectin）水平升高；且血液透析全程中，平均血小板体积与血小板大细胞比率均显著降低。未观察到灌注边界区、可溶性E-选择素（sE-Selectin）、可溶性细胞间黏附分子-1（sICAM-1）以及可溶性血管细胞黏附分子-1（sVCAM-1）出现显著变化。
**结论：** 血液透析可使多配体聚糖-1水平显著升高，而灌注边界区无明显变化。低分子肝素的给药时机似乎先于多配体聚糖-1的水平升高。