Plasma endotoxin concentration and endotoxin binding capacity of plasma acute phase proteins in cirrhotics with variceal bleeding: An analysis by new methods

Plasma endotoxin levels in 12 cirrhotics with bleeding from oesophageal varices and 50 cirrhotics without bleeding were measured by the chromogenic assay after the pretreatment of sample by perchloric acid (HClO₄) and triethylamine. Endotoxin in cirrhotics with bleeding from varices was significantly higher than those without bleeding. In patients with bleeding, endotoxin increased for 3 days after the bleeding, first in the supernatant fraction and then in the precipitate fraction by HClO₄ treatment. Peak plasma α₁-acid glycoprotein and haptoglobin were observed 3 days after the bleeding. Alpha 1-antitrypsin gradually increased for 14 days. Transferrin did not markedly change. The endotoxin-binding capacity of transferrin and α₁-acid glycoprotein increased immediately after bleeding and thereafter decreased, but that of α₁-antitrypsin tended to increase in the recovery period. In summary, the plasma endotoxin concentration and endotoxin-binding capacity of α₁-acid glycoprotein and transferrin were shown to have increased after bleeding from varices by this new method. There may be a close relationship between endotoxaemia and acute phase reaction in this situation.     

Endotoxaemia in patients with liver cirrhosis and upper gastrointestinal bleeding: Detection by the chromogenic assay with plasma Tween 80 pretreatment

A recently developed chromogenic endotoxin assay with plasma Tween 80 pretreatment was compared with the conventional dilution and heating method. Plasma endotoxin was measured in patients with liver cirrhosis and upper gastrointestinal (GI) bleeding by these methods. Plasma endotoxin concentration was calculated from an individual internal standard curve by adding three different standard endotoxin solutions to each sample. By the conventional heating method, added standard endotoxin gave different OD values in each sample and the slope of the standard curve showed interindividual variations. When sample plasma from chronic alcoholics was pretreated with 1% Tween 80 and ultrasonification after heating, the slope of standard curves was somewhat increased and interindividual variation was minimized. Significantly higher plasma endotoxin levels in cirrhotics with upper GI bleeding compared with those without upper GI bleeding was detected by this Tween 80 method. There was a strongly positive correlation between the endotoxin levels determined by this method and those determined by the perchloric acid method and endotoxin-specific substrate in patients with upper GI bleeding. Endotoxin levels, which were elevated 1–2 days after the bleeding, tended to decrease as patients recovered. In summary, the recovery of endogenous and exogenous endotoxin from plasma sample was increased by adding Tween 80 before the chromogenic substrate assay. Transient elevation of plasma endotoxin was demonstrated by this Tween 80 method in patients with liver cirrhosis and upper GI bleeding.     

Serial Intravascular Ultrasound Analysis of the Impact of Myocardial Bridge on Neointimal Proliferation After Coronary Stenting in Patients with Acute Myocardial Infarction

Background: Mechanisms underlying the association between myocardial bridge (MB)‐stenting and in‐stent restenosis (ISR) are still unclear. Objective: To assess the impact of MB on ISR using intravascular ultrasound (IVUS). Methods: In the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS‐AMI) trial, 100 left anterior descending artery (LAD) culprit lesions (79 treated with paclitaxel‐eluting stents [PES] and 21 treated with bare metal stents) were imaged with serial IVUS immediately postprocedure and at 13 months. Results: At baseline the LAD stent extended into the MB segment beyond the culprit lesion in seven patients (MB‐stent group). In the remaining 93 patients the LAD stent was implanted only in the culprit lesion without extending into the MB segment (non‐MB‐stent group). In PES‐treated lesions intimal hyperplasia (IH) was greater in MB‐stent group than in non‐MB‐stent group (1.0 [0.9, 1.3] mm² vs. 0.4 [0.2, 0.7] mm², P = 0.007). When comparing the MB‐stent segment with the non‐MB‐stent segment in the MB‐stent group treated with PES, a significant reduction in lumen area was observed in only the MB‐stent segment, owing to an augmented IH within the MB‐stent segment (1.56 [1.40, 1.91] mm² vs. 0.77 [0.55, 1.23] mm² for non‐MB‐stent segment, P = 0.08), not significant stent recoil (Δstent area). At follow‐up, the minimum lumen area was smaller in the MB‐stent group than in the non‐MB‐stent group (2.9 [2.5, 4.2] mm² vs. 5.2 [4.1, 6.7] mm², P = 0.02). Conclusions: Increased incidence of ISR associated with MB‐stenting may be attributable to enhanced IH, specific to stented MB segment, not to chronic stent recoil. (J Interven Cardiol 2010;23:114‐122)