Antiinflammatory effects of reconstituted high-density lipoprotein during human endotoxemia.

High-density lipoprotein (HDL) has been found to neutralize LPS activity in vitro and in animals in vivo. We sought to determine the effects of reconstituted HDL (rHDL) on LPS responsiveness in humans in a double-blind, randomized, placebo-controlled, cross-over study. rHDL, given as a 4-h infusion at 40 mg/kg starting 3.5 h before endotoxin challenge (4 ng/kg), reduced flu-like symptoms during endotoxemia, but did not influence the febrile response. rHDL potently reduced the endotoxin-induced release of TNF, IL-6, and IL-8, while only modestly attenuating the secretion of proinflammatory cytokine inhibitors IL-1ra, soluble TNF receptors and IL-10. In addition, rHDL attenuated LPS-induced changes in leukocyte counts and the enhanced expression of CD11b/CD18 on granulocytes. Importantly, rHDL infusion per se, before LPS administration, was associated with a downregulation of CD14, the main LPS receptor, on monocytes. This effect was biologically relevant, since monocytes isolated from rHDL-treated whole blood showed reduced expression of CD14 and diminished TNF production upon stimulation with LPS. These results suggest that rHDL may inhibit LPS effects in humans in vivo not only by binding and neutralizing LPS but also by reducing CD14 expression on monocytes.

Reconstituted high density lipoprotein (rHDL) modulates platelet activity in vitro and ex vivo.

A reconstituted high density lipoprotein (rHDL) prepared for clinical use was tested for its influence on platelet activity modulated by various stimuli. In a first series of in vitro experiments, rHDL was added to blood in a concentration series, and platelet rich plasma (PRP) was isolated. Platelets were stimulated with arachidonic acid, collagen, epinephrine or ADP, and platelet aggregation was assessed. rHDL mediated a dose dependent inhibition of the platelet activity. With purified platelets rHDL inhibited the release reaction induced by collagen, but not by thrombin, as measured by CD62P (P-Selectin) expression on the plasma membrane. Ex vivo experiments were performed with PRP from volunteers, previously infused with 25 mg rHDL/kg body weight and 40 mg rHDL/kg body weight, respectively. Platelet activity in PRP was assessed before, and up to 30 h after the end of the rHDL infusion. A transient inhibition of the platelet aggregation induced by arachidonic acid and collagen was observed which was more pronounced in the group receiving 40 mg rHDL/kg body weight. In both groups of experiments, in vitro and ex vivo, the inhibition of the platelet activity was also dependent on the stimulus used.

Differential effects of reconstituted high-density lipoprotein on coagulation, fibrinolysis and platelet activation during human endotoxemia.

High-density lipoproteins (HDL) can bind and neutralize lipopolysaccharides (LPS) in vitro and in vivo. HDL can also affect fibrinolytic activity and can directly influence platelet function by reducing platelet aggregation. In this study, the effects of reconstituted HDL (rHDL) on LPS-induced coagulation, fibrinolysis and platelet activation in humans were investigated. In a double-blind, randomized, placebo-controlled, cross-over study, eight healthy male volunteers were injected with LPS (4 ng/kg) on two occasions, once in conjunction with rHDL (40 mg/kg, given as a 4 h infusion starting 3.5 h prior to LPS injection), and once in conjunction with placebo. rHDL significantly reduced LPS-induced activation of coagulation (plasma levels of prothrombin fragment F1 + 2) and fibrinolysis (plasma levels of tissue type plasminogen activator antigen, t-PA). No effect was observed on LPS-induced inhibition of the fibrinolytic pathway (PAI-1) or on the transient thrombocytopenia elicited by LPS. Furthermore, rHDL treatment significantly enhanced the inhibition of collagen-stimulated inhibition of platelet aggregation during endotoxemia, but had no such effect on arachidonate-stimulated platelet aggregation. rHDL treatment per se also reduced collagen-induced platelet aggregation. These results indicate that rHDL modifies the procoagulant state associated with endotoxemia.

Reconstituted high density lipoprotein modulates adherence of polymorphonuclear leukocytes to human endothelial cells.

A reconstituted high density lipoprotein (rHDL) containing human apolipoprotein A-I and phosphatidylcholine was tested for its ability to modify polymorphonuclear leukocyte (PMN) adherence to endothelial cells (EC) in vitro. EC stimulation for 4 h with lipopolysaccharide (LPS) or tumor necrosis factor-alpha (TNF alpha) resulted in a four- to sixfold increase in PMN adherence. Concomitant stimulation of EC with LPS and rHDL virtually prevented the LPS-stimulated increase in PMN adherence. Changes in adherence were paralleled by alterations in adhesion molecule expression of EC. Concomitant EC stimulation with LPS and rHDL resulted in complete inhibition of the LPS-stimulated increase in expression of E-selectin and intercellular adhesion molecule 1 (ICAM-1). In contrast, rHDL reduced the TNF alpha-induced expression of adhesion molecules as well as the PMN adherence to TNF alpha-stimulated EC by approximately 10%. The CD11/CD18-mediated PMN adherence to EC as a consequence of PMN stimulation with calcium ionophore (A23187) was diminished in the presence of rHDL after 7 min incubation by 36.1 +/- 11.4% and after 15 min incubation by 45.1 +/- 7.4%. In addition, the A23187-stimulated increase in PMN adherence to fibrinogen-coated surfaces, mediated by CD11b/CD18, was virtually eliminated in the presence of rHDL and HDL, but not in the presence of apolipoprotein A-I or natural low density lipoprotein. FACS analysis showed that PMN treated with rHDL and subsequently washed were resistant to FMLP-induced CD11b/ CD18 up-regulation. In conclusion, these data indicate that rHDL decreases cell adhesion via two mechanisms: blocking LPS activity and modifying CD11b/CD18 up-regulation on PMN.

Effects of high-dose aprotinin on blood loss, platelet function, fibrinolysis, complement, and renal function after cardiopulmonary bypass.

The use of aprotinin to reduce blood loss after cardiopulmonary bypass is under debate. Concern has been raised about the renal effects of aprotinin. We administered a mean aprotinin dose of 4.2 x 10(6) kallikrein-inhibiting units to 13 patients with coronary disease undergoing cardiopulmonary bypass for 74 +/- 5 minutes (mean +/- standard error of the mean); 13 comparable patients having cardiopulmonary bypass served as control subjects, and all were studied postoperatively for 24 hours. Aprotinin reduced postoperative blood loss by 50% (p = 0.0082). Two of the 13 patients who received aprotinin needed one red cell unit each versus a total of 18 units in eight of 13 control patients (p = 0.0096). Blood pressure, hemoglobin value and serum protein concentration were higher after operation in the aprotinin group (p less than 0.05 to p less than 0.01). Platelet counts did not differ, but plasma thromboxane was lower in aprotinin recipients (p less than 0.001). In control patients fibrinogen degradation products (D dimer) doubled, and alpha 2-antiplasmin activity was halved during and after cardiopulmonary bypass (p less than 0.01 to p less than 0.001), whereas aprotinin patients showed no changes. The complement breakdown products C4a, C3a, and C3dg as well as C9 neoantigen increased from prebypass baseline in both groups (p less than 0.001); the increment of C3a and C3dg was greater in the aprotinin than in the control patients (p less than 0.001). Serum electrolytes, osmolality, and creatinine remained normal in both groups of patients. Creatinine clearance was normal or above normal and virtually identical in both groups. Osmolar clearance and fractional sodium excretion were higher in the aprotinin group than in the control group shortly after cardiopulmonary bypass (p less than 0.05 to p less than 0.01); renal function was unremarkable the next morning. No adverse clinical effects attributable to aprotinin were seen. In summary, aprotinin offers advantages for cardiopulmonary bypass.

Comparison of the effects of aprotinin and tranexamic acid on blood loss and related variables after cardiopulmonary bypass.

Aprotinin reduces blood loss after cardiopulmonary bypass, but may sensitize recipients and is expensive. Tranexamic acid, a synthetic antifibrinolytic, has less disadvantages, but opinions differ regarding its efficacy. We studied three groups of patients undergoing cardiopulmonary bypass for coronary disease: recipients of aprotinin (total dose 4.2 x 10(6) kallikrein inhibiting units, n = 14), recipients of tranexamic acid (total dose 20 mg/kg body weight, n = 15), and nonmedicated controls (n = 14) during 24 hours after cardiopulmonary bypass. Compared with controls, aprotinin reduced blood loss, the number of patients requiring transfusions, and the mean number of transfused red cell units (all with p < 0.05), whereas the recipients of tranexamic acid did not differ either from aprotinin recipients or from controls. Aprotinin and tranexamic acid both mitigated the early postoperative reduction of adenosine diphosphate-induced platelet aggregation seen in the controls (p < 0.05). Postoperative increases of plasma concentrations of the prothrombin activation fragment F1 + 2 and the thrombin-antithrombin III complex showed an activation of intravascular coagulation, without any intergroup differences. The balance between concentrations of tissue plasminogen activator and the type 1 plasminogen activator inhibitor disclosed an activation of fibrinolysis, without differences between the groups. The concentrations of D-dimer, a breakdown product of cross-linked fibrin, remained at baseline in the recipients of aprotinin and tranexamic acid but tripled in the controls (p < 0.05). By contrast, the plasma antiplasmin activity was equally depressed in the tranexamic acid and the control groups but decreased less in the recipients of aprotinin (p < 0.05). This discrepancy may reflect the different modes of action of the two agents, which may make aprotinin more efficacious than tranexamic acid in the "nonfibrinolytic" act of protecting platelet function against attack by plasmin during cardiopulmonary bypass.

Serum concentrations of immunoglobulins and of antibody isotypes in bone marrow transplant recipients treated with high doses of polyspecific immunoglobulin or with cytomegalovirus hyperimmune globulin.

The kinetics of immunoglobulins (Ig) and antibodies were followed in 10 bone marrow transplant recipients who received either high doses (0.5 g/kg body weight) of polyspecific intravenous Ig (HD-IVIG) weekly or cytomegalovirus hyper-Ig (CMV-IVIG, 0.1 g/kg body weight) every 3 weeks. In the HD-IVIG group, the mean total IgG concentration more than tripled and similar significant increases were seen for IgG1 and IgG2. IgG antibodies to CMV showed a marked increase in the HD-IVIG and a less pronounced rise in the CMV-IVIG group. IgM antibodies to CMV were present initially or became detectable in five patients, unrelated to the IVIG preparation. HD-IVIG induced a significant increase of IgG antibodies to streptococcal group A carbohydrate (A-CHO) and to smooth strain lipopolysaccharides (LPS) but not of antibodies against lipid-A. When the Ig treatment was discontinued, levels of total IgG and of IgG antibody to CMV decreased with an apparent half-life of 30 days. Both IVIG preparations were well tolerated and had no negative feedback on total Ig and on specific antibody production or other antimicrobial defence mechanisms. In patient nos. 4 and 10 who developed severe graft-versus-host-disease, transient serum Ig peaks including several Ig isotypes appeared after day 14. In patient no. 10 this peak contained an IgG antibody to H. influenzae type b (Hib), and IgM antibodies to CMV, Hib, A-CHO and LPS. This study clearly shows that serum concentrations of Ig isotypes, subtypes and specific antibodies, depend on at least four factors: total amount and composition of Ig infused, consumption, catabolism and endogenous production.

Plasma fibronectin: relevance for anesthesiology and intensive care.

Plasma fibronectin has been postulated to be an essential mediator of normal reticuloendothelial system (RES) function. The acute depletion of fibronectin is thought to impair RES function, whereas its repletion in states of deficiency has been reported to improve RES function. In vitro studies have documented fibronectin's ability to bind to some nonbacterial microaggregates and to promote the phagocytosis of bound targets by the RES. These properties may, however, be influenced by the in vivo milieu. There is substantial evidence for a parallelism between RES function and plasma fibronectin levels following blunt trauma in animal models; however, this association is not seen in experimentally induced intravascular coagulation, acute inflammation, and sepsis. Clinically, subnormal fibronectin levels are clearly associated with the triad of intravascular coagulation, organ failure and sepsis. Fibronectin is, however, not the only plasma protein reduced in these patients, nor is it an outstanding predictor of such complications. The therapeutic efficacy of fibronectin administration remains controversial. Whereas initial reports suggested therapeutic benefits of fibronectin-enriched cryoprecipitates, subsequent studies have produced negative results. Prospective, randomized, controlled clinical trials with purified fibronectin are needed before fibronectin should be recommended as an adjunct to the established principles of intensive care.

Effect of cholecystectomy on cold insoluble globulin.

Levels of cold insoluble globulin (CIG), also called opsonic alpha2 surface-binding glycoprotein, humoral recognition factor, and fibronectin, are depressed as a result of major trauma. This protein normally promotes the phagocytosis and removal of abnormal particles and bacteria by cells of the recticuloendothelial system. Although CIG depends on macrophages as the effector cells for its opsonic function as is true of both antibody and complement, CIG is neither part of nor dependent on these systems for its opsonic activity. Using a new, rapid bioassay, we have demonstrated that in humans subjected to operative trauma, circulating CIG levels are considerably depressed in the early hours after operation and return to normal within 24 hours. The observed decreases in titer varied in extent, time of onset, and duration. Continuing study is designed to determine potential correlation between initial levels of CIG, decreases in titer resulting from operation, and the incidence of postoperative infection.

Reconstituted high density lipoprotein inhibits physiologic and tumor necrosis factor alpha responses to lipopolysaccharide in rabbits.

OBJECTIVE: To determine the effect of reconstituted human high density lipoprotein (rHDL) on physiologic and cytokine responses to infusion of lipopolysaccharide. DESIGN: A blinded, randomized trial of three preparations of a purified human rHDL with apolipoprotein A-I-phosphatidyl choline-cholesterol molar ratios of 1:100:10, 1:150:10, and 1:200:0 and placebo in a rabbit lipopolysaccharide intravenous infusion model. INTERVENTIONS: Groups of six New Zealand white rabbits received either placebo or one of the three human rHDL preparations above as a single, 75-mg/kg (apolipoprotein A-I equivalent) dose intravenously over 10 minutes ending 5 minutes before the start of a 3-hour infusion of lipopolysaccharide. MAIN OUTCOME MEASURES: Mean arterial pressure, base excess, and plasma tumor necrosis factor alpha (TNF-alpha) production were determined. RESULTS: The human rHDL suppressed TNF-alpha production with the products having the highest fraction of phosphatidyl choline producing the greatest suppression of TNF-alpha production. The human rHDL 1:200:0 group maintained a low, near-baseline TNF-alpha concentration and minimal decline in mean arterial pressure and base excess throughout the lipopolysaccharide infusion in contrast to the placebo group. CONCLUSION: Reconstituted human high density lipoprotein appears to be useful in inhibiting the physiologic effects and cytokine release associated with endotoxemia and may provide adjunctive treatment for patients with gram-negative sepsis.

An investigation of 2':3'-cyclic nucleotide 3'-phosphodiesterase (EC 3.1.4.37, CNP) in peripheral blood elements and CNS myelin.

Activity of 2':3'-cyclic nucleotide 3'-phosphodiesterase (CNP) of human erythrocyte membranes was determined in the presence of various brain CNP inhibitory compounds. Also, the hydrolysis of 2':3'-cAMP and 2':3'-cCMP by CNP of human platelets and lymphocytes was confirmed by thin layer chromatography and CNP activity was measured in lymphocytes, platelets, erythrocytes and CNS myelin. Human erythrocyte CNP activity was reduced 75 percent by the organomercurial p-chloromercuriphenyl sulfonate (1 X 10(-4) M), 46 percent by thimerosal (1 X 10(-4) M) and 35 percent by cupric chloride (1 X 10(-3) M). The 2'-AMP or 2'-CMP isomer was produced, exclusively, by the hydrolysis of 2':3'-cAMP or 2':3'-cCMP, respectively, by CNP of human lymphocytes and platelets and indicates a CNP-like activity is not only present in erythrocytes and the central and peripheral nervous systems, but also platelets and lymphocytes. CNP activities of human erythrocytes, human human and rat lymphocytes and human platelets were less than 4 percent of the activity of human and bovine CNS myelin.

Clinical response to cold insoluble globulin replacement in a patient with sepsis and thermal injury.

Cold insoluble globulin (fibronectin, alpha 2-surface binding glycoprotein) is a naturally occurring substance necessary for optimal stimulation of the reticuloendothelial system. While this globulin depends on macrophages as the effector cells for its opsonic function, as is true of both antibody and complement, it is neither part of nor dependent on these systems for its opsonic activity. A relatively simple bioassay developed at the Medical College of Georgia substantiated that cold insoluble globulin is severely depleted in sepsis. Cryoprecipitate, properly processed and stored, is an exogenous source of cold insoluble globulin. Infused into septic patients 10 units thawed at 2 degrees C and reconstituted to 250 ml with saline solution can temporarily restore cold insoluble globulin levels and enhance activity of the reticuloendothelial system. Proper current use dictates measurement of cold insoluble globulin levels in the infusate as well as levels in the patient and the clinical response to infusion. Our bioassay and a septic patient's response to infusion of cold insoluble globulin are reported herein.

Effects of reconstituted high-density lipoprotein in persistent gram-negative bacteremia.

Reconstituted high-density lipoproteins (rHDL) have been shown bind bacterial LPS and reduce its toxic effects. Since the effect of rHDL on LPS in vitro cannot be directly extrapolated to the in-vivo picture of Gram-negative septic shock, we have investigated the effects of rHDL in a rabbit model of Gram-negative bacteremia. Rabbits were anesthetized, ventilated, and invasively monitored for 6 hours. Escherichia coli (4 x 10(9) CFU/kg) were infused over 2 hours in rabbits given rHDL (75 mg/kg) before the bacterial challenge. Antibiotics were not used in this model. The bacterial infusion resulted in a bacteremia that persisted until the end of the study. The sepsis-induced TNF peak was significantly lowered by rHDL treatment (10 +/- 3 ng/mL in rHDL treated versus 33 +/- 5 in controls, P = 0.001). Blood pressure, although not statistically significant, tended to be higher in the rHDL group. Acidosis was significantly attenuated up to 3 hours after the beginning of the bacterial challenge (7.39 +/- 0.05 versus 7.27 +/- 0.05 in controls, P = 0.041). rHDL treatment produced some transient beneficial effects in this model of persistent Gram-negative bacteremia. Additional studies, investigating the effects of rHDL in combination with antibiotics, are warranted.

[The mobile cecum syndrome: appendectomy and cecopexy or only appendectomy?]. / Das Coecum mobile-Syndrom: Appendektomie und Cöcopexie oder nur Appendektomie?

1159 patients underwent appendectomy via a McBurney incision from 1972 to 1983 at our institution. 115 patients (10%) had a mobile cecum syndrome (CMS) as defined by Nicole, without evidence of appendicitis or other pathologic findings at operation. 102 patients were followed up to 15 years after the operation. 82% of the 102 patients were free of symptoms at assessment. 36 patients underwent appendectomy and 63 appendectomy and cecopexy. The two cohorts were comparable with respect to sex, age at operation, duration of right lower abdominal pain, operative findings and length of follow-up. There was no significant difference in the postoperative result of patients with appendectomy alone and those with appendectomy and cecopexy. Moreover, we were not able to identify patients who may benefit from an additional cecopexy, on the basis of patient related factors or intraoperative findings.

[Long-term results following surgery of varicose veins]. / Langzeitresultate nach Varicenoperation.

In a long-term follow-up after operation for primary varicose vein disease, patients were revisited 5, 10 and 15 years after their operation, in an attempt to define the goal of the treatment and the result. The results were analyzed as well as those factors which had a significant influence on the findings at assessment. The long-term results were good with respect to the patient's self-judgement and relative to improvement of trophic disturbances, especially of venous ulceration, however recurrent superficial varicose veins increase significantly with increasing follow-up time. The outstanding role of incompetent communicating veins is discussed with respect to trophic disturbances and recurrent varicose veins.