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Background and Aims: Both fracture and fracture treatment affect bone mineral density (BMD). BMD after standard intramedullary reaming of the femoral cavity and after reaming with a reamer-irrigator-aspirator (RIA) system were studied with the hypothesis that the RIA technique would lead to lower BMD levels.Material and Methods: Dual-energy X-ray absorptiometry (DXA) was performed on the third day after operation with standard intramedullary nailing technique (n = 6)or RIA technique (n = 7) in intact femora of young Norwegian landrace pigs.Results and conclusion: Significantly lower BMD were found in the mid-shaft and total femur after reaming with the RIA technique compared to the non-operated femur. Traditional reaming technique resulted in significantly higher BMD in the distal femur.Interpretation: The results of this study indicate that standard reaming increased BMD in the distal femur, suggesting compressive effects on trabecular bone. The RIA technique decreased BMD in the femoral diaphysis and total femur, suggesting removal of trabecular bone. A possible clinical impact of the findings remains to be investigated.

Background: Fibrinolysis in blood is mainly reflected by the activities of tissue plasminogen activator (tPA) and of plasminogen activator inhibitor‐1 (PAI‐1). The effect of myocardial ischemia on their activities in the coronary circulation is, however, not established. Objectives: With an improved experimental model, we therefore examined the effect of a brief period of myocardial ischemia on their activities. Furthermore, the consequences of repeated periods of ischemia, mimicking the situations in patients with unstable angina, were investigated. Methods: In six anesthetized pigs, we occluded the distal left anterior descending coronary artery (LAD) four times for 10 min with 40 min intervals and determined the activities of tPA and PAI‐1 in arterial and coronary venous blood. By simultaneously recording LAD flow, we could estimate cardiac release of these factors at baseline conditions and during reperfusion. Results: Neither net cardiac release of PAI‐1 nor alterations in plasma PAI‐1 levels were demonstrated during the experiment. However, a significant net release of tPA activity of 10.4 ± 3.2 IU mL−1(P < 0.005) was recorded during baseline conditions. During reperfusion following the first period of ischemia, the cardiac release of tPA activity increased to a peak of 103 ± 30‐fold baseline release, but declined progressively after repeated periods of ischemia. After the fourth period, tPA release did not exceed an estimated baseline accumulation during ischemia and early reperfusion. Conclusions: In this porcine model, a substantial local increase in fibrinolytic capacity was observed after brief periods of ischemia, but declined subsequently by repeated periods of ischemia.

In a randomized trial on the effect of dalteparin for 5 weeks after HRS we evaluated hemostatic variables in plasma sampled before and 1, 6 and 35 days postoperatively. In 218 patients we found that prothrombin fragment 1 + 2 (F1 + 2), thrombin–antithrombin complexes (TAT), d-dimer and fibrinogen were significantly higher on day 35 as compared with baseline values in the placebo group (P < 0.001 for all). The same pattern was found in the dalteparin group, but with significantly lower values for F1 + 2, TAT and d-dimer. In patients in the placebo group with venographically proven deep vein thrombosis (DVT) on day 35 (33%), significantly higher values were found for F1 + 2, TAT and d-dimer than in patients without DVT. Patients in the highest quartile of d-dimer (>2850 ng mL−1) had an odds ratio for the presence of DVT of 24.0 when compared with patients in the lowest quartile (<1625 ng mL−1). It is concluded that a substantial hypercoagulability is sustained until day 35 after HRS, significantly reduced with prolonged administration of dalteparin.

To elucidate the innate immune responses to group A streptococci (GAS) important in the pathophysiology of sepsis, flow cytometric techniques were applied to study the effects of live and heat-inactivated GAS, including their particulate and soluble components, on the expression of leukocyte adhesion molecules CD11b (Mac-1) and CD62L (L-selectin), and leukocyte production of reactive oxygen species (ROS) in human whole blood. GAS caused marked time- and concentration-dependent increases in CD11b and ROS, while CD62L was downregulated. Live and heat-inactivated GAS induced similar changes in leukocyte adhesion molecules, whereas ROS production induced by heat-inactivated GAS (and its particulate fraction) was 4 (2.5)-fold higher than with live GAS. Leukocyte nitric oxide production (24 h) was not enhanced. Although GAS proved a more potent inducer of ROS production, leukocyte responses to GAS were similar to those reported for lipolysaccharides, indicating that Gram-positive and Gram-negative bacteria activate common pathways in the inflammatory response. High ROS production may contribute to tissue damage caused by GAS.

Different anaesthetic methods influence the neuro-immuno-endocrine biologic responses to surgery and may thus possibly interfere with the postoperative course and development of complications. The neuroendocrine system is closely related to the cytokine network. In this study, the effects of general anaesthesia (n=6) and regional spinal/epidural anaesthesia (n=6) on the cytokine response (IL-1β, TNFα, IL-6) to uncemented total hip replacement surgery were evaluated. The postoperative clinical course was uneventful in every case. In both groups, only very low values of plasma IL-β were measured perioperatively, whereas plasma IL-6 increased postoperatively with peak values 4h after surgery. The changes in plasma TNF-α were not significant. No significant differences in plasma TNF-α or IL-6 were found between patients operated in general or in regional anaesthesia. This suggests minor influence of plasma cytokines on the possible beneficial effects of regional anaesthesia on the clinical course after surgery in low risk patients. There were slightly higher TNF-α and IL-6 levels after the operation and significantly lower cortisol levels during the operation in the regional anaesthesia group compared to the general anaesthesia group, giving rise to a significant inverse correlation between peak values of IL-6 and peak values of cortisol. This supports the theory that after surgery the inhibitory effect of cortisol on monocyte cytokine production overrides adrenergic stimulation.

BACKGROUND: Platelet-harvesting technology differs in various cell separators. Alteration in shear stress and biocompatibility of surfaces may give variable platelet activation and thereby affect the quality of the component. STUDY DESIGN AND METHODS: Four groups (n = 10) of single-needle apheresis procedures using three cell separators, were compared: 1) Spectra LRS, 90-minute harvesting time; 2) MCS+, 90-minute harvest; 3) Amicus, 90-minute; and 4) Amicus, 45-minute. Whole-blood samples were collected from the donors as were samples from the final components at intervals during the first 4 hours after cessation of the apheresis. Platelet activation status and platelet activation capacity after agonist stimulation were assessed by flow cytometry. RESULTS: No activated platelets were found in preapheresis and postapheresis samples from the donors. The platelets in the components from the Amicus (90-min) were significantly more activated than those in the other groups of components: that is, there was increased size of platelet aggregates, increased fraction of microparticles, increased degranulation, increased fibrinogen receptor activation, and decreased von Willebrand factor receptor expression. Moreover, the response of these platelets to agonist stimulation was reduced for all activation variables. CONCLUSIONS: After 90 minutes' processing time, platelets obtained with the Amicus cell separator were significantly more activated than platelets harvested with the Spectra and the MCS+.

We have studied the expression of the lipopolysaccharide (LPS) receptor CD14 on monocytes (Mo) and alveolar macrophages (AM), including density- and size-defined subpopulations. Bronchoalveolar lavage (BAL) was performed on eleven healthy non-smokers and blood sampled from 5 of them, and the levels of cell CD14 expression was investigated using flow cytometry. The influence of LPS stimulation on the CD14 expression of AM was studied at various intervals during prolonged incubation. Further, the relationship between CD14 expression and LPS binding to Mo and subpopulations of AM was studied by measuring fluorescein isothiocyanate (FITC)-LPS binding (flow cytometry) and binding of radioiodinated LPS (I25I-LPS). The CD14 expression was 13-fold higher (P< 0.02) on Mo than on unfractionated and high density AM. The CD14 level on the latter was higher than on low density AM, and also higher (P< 0.05) on small AM compared to large (flow cytometrically defined) AM. LPS stimulation had a downregulating effect on AM CD14 level, but after several hours of continuing decreased expression, an increased (P< 0.05) CD14 expression was demonstrated, indicating de novo synthesis. The binding of LPS to subpopulations of AM and isolated Mo was not significantly different, but the binding of FITC-LPS to Mo in whole blood was higher than to AM (P< 0.02). The presented results indicate that AM of different size and maturity have different and variable (activation dependent) CD14 levels. The LPS binding capacity was, however, not proportional to the CD14 expression, indicating that LPS binding mechanisms unrelated to CD14 levels were also operable.

Background: Large intravenous bilirubin infusions in bile acid-depicted pigs (BADF) destroy hepatocyte canalicular membrane microvilli (CMV) and cause cholestasis. This study examines whether bilirubin photoconversion product infusions do the same. Methods: The effects of systemic infusion of 135 µmol - kg-1 body weight bilirubin photoconversion products on CMV density and cholcretic response to intruportal bile acid infusion were studied in BADP. Furthermore, the effects of 135 µmol - kg-1 b.w. bilirubin infusion, cither through an artcriovenous bilirubin photoconversion shunt device (PCD) or intravenously, were measured in PCD-connected BADP. Results: Intravenous bilirubin photoconversion product infusions affected neither the CMV density nor the choleretic response to cholic acid infusion, and neither did bilirubin infusion through the PCD. In contrast, intravenous bilirubin infusion caused canalicular injury and cholestasis in four of six PCD-connected 13ADP. Conclusion: Bilirubin photo-conversion products do not destroy CMV or cause cholestasis in BADP. A bilirubin photoconversion shunt device can confer cholestasis protection to bilirubin-loaded BADP.

In severe trauma, sepsis or during surgery, bacterial lipopolysaccharide (LPS) frequently enters the circulation. Persons with high levels of high-density lipo-protein (HDL) have previously demonstrated higher monocyte procoagulant activity (PCA) when whole blood is challenged with LPS. The aim of the study was to investigate the distribution of radiolabelled LPS (125I-LPS) in plasma from six persons with high (2.14-2.82 mmol 1-1) and six persons with low (0.54-1.04 mmol 1-1) HDL, subjecting plasma to fast protein liquid chromatography (FPLC), or agarose electrophoresis followed by quantitative autoradiography. In heparin plasma 125I-LPS was located mainly in parts of plasma containing low-density lipoprotein (LDL) or very low-density lipoprotein (VLDL) and the immunoglobulins, and located to a lesser extent in HDL. However, persons with high HDL showed significantly higher binding of 125I-LPS to HDL and the immunoglobulins, probably to IgG, and significantly lower binding to LDL/VLDL. In calcium-depleted plasma (EDTA) 125I-LPS demonstrated a sharp increase in the binding to HDL, combined with a persistently high binding to LDL/VLDL and binding to the immunoglobulins was almost eliminated in all subjects investigated. Likewise, the binding of 125I-LPS to HDL in EDTA plasma was also significantly higher and to LDL/VLDL significantly lower in persons with high HDL. This study demonstrates that the distribution of 125I-LPS in heparin and EDTA plasma from persons with high or low HDL is different, which is presumed to be of importance concerning the various bioactivities of LPS.

12-O-Tetradecanoylphorbol 13-acetate (TPA), phorbol 12,13-diacetate and phorbol 12,13-didecanoate were all potent inducers of thromboplastin activity in human monocytes in vitro, whereas 4 alpha-phorbol 12,13-didecanoate and 4 alpha-phorbol had no such effect. A concomitant increase in titrable apoprotein III antigen was found (apoprotein III is the protein component of thromboplastin). The increase was inhibited by cycloheximide and actinomycin D and partly by alpha-amanitin. The increase of thromboplastin activity was therefore most likely due to synthesis de novo of apoprotein III. The response was approximately halved in the absence of serum or Ca2+. Retinol had a weak inhibitory effect, and retinoic acid was inhibitory only at concentrations that also induced signs of cytotoxicity. TPA caused an initial rise in monocyte cyclic AMP concentration of about 90-120 min duration. No increase in 45Ca2+ influx was induced over 2 h. Good correlation exists between induction of apoprotein III synthesis in monocytes in vitro and mouse skin-tumour promotion in vivo by the various phorbol derivatives. Substances inactive in tumour promotion do not induce the synthesis of apoprotein III. General activating and cytotoxic effects of TPA were monitored by determining release of lysozyme, beta-glucuronidase and lactate dehydrogenase.

Endotoxin interacts with several plasma protein systems and blood cells, causing release of a multitude of endogenous mediators that contribute to the pathophysiological process of sepsis. Binding of 125I-labelled lipopolysaccharide, LPS, to human blood in vitro showed that the major part of the 125I-LPS was recovered in plasma, whereas only small amounts were retained in washed suspensions of granulocytes, erythrocytes, monocytes and lymphocytes, respectively. Whole leukocyte preparations or isolated subpopulations incubated with 125I-LPS or fluoresceinconjugated LPS followed by autoradiography, flow cytometry or immunofluorescence microscopy showed unequivocally that monocytes bound much more LPS than did granulocytes and lymphocytes. Lipoprotein electrophoresis followed by autoradiography showed that 125I-LPS bound to all the purified lipoprotein fractions, which was also confirmed by gel filtration chromatography. These findings demonstrate that monocytes represent the most important blood cell for LPS binding and that radiolabelled LPS is able to bind to lipoproteins as well as to other serum constituents.

Upon stimulation with lipopolysaccharides (LPS), monocytes are able to produce tissue factor (TF), the most powerful physiological procoagulant substance known. In several assay systems LPS bound to lipoprotein has been reported to be less active than unbound LPS in stimulating monocytes. In the present study the LPS-induced TF activity was, however, not prevented by lipoproteins (VLDL, LDL, HDL). In fact, the very low density (VLDL) fraction further increased the TF inducing capacity of LPS. The lipoproteins per se mediated reduced plasminogen activator (PA) production in monocytes. LPS had an even more and significant depressing effect on PA production, which was not further decreased in the presence of lipoproteins. Furthermore, LPS-induced release of tumour necrosis factor (TNF), a marker of monocyte activity, was not inhibited by lipoproteins. Our experiments suggest that lipoproteins do not render LPS less effective in stimulating TNF release, procoagulant and fibrinolytic activities in human monocytes.

A new technique (palatopharyngoglossoplasty (PPGP)) has been developed for surgical treatment of patients with the obstructive sleep apnea syndrome (OSAS). In 20 operated patients 18 reported immediate marked improvement of daytime sleepiness, alertness and vigilance during the day, and of working capacity. However, polysomnography carried out pre- and postoperatively showed that only 10 patients were "cured", defined as 50% or more reduction in apnea/hypopnea index (AHI). Cephalometric analysis pre- and postoperatively indicated that nonresponders had a long and narrow posterior airway space, and we suggest that during sleep this part of the upper airway collapses before as well as after the operation. The discrepancy between the subjective improvement observed after PPGP and the postoperative reduction in AH1 may be due to reduced/eliminated snoring and/or improvement in sleep quality after the operation.

Uvulopalatopharyngoglossoplasty, UPPGP, is a modification of the uvulopalatopharyngoplasty, UPPP, technique, originally used for surgical treatment of the obstructive sleep apnea syndrome. The first method seems to be the more successful. However, polysomnography performed after UPPGP showed that about 35% of the patients still had obstructive apnea periods during sleep. Eight of these patients were reoperated with a new technique which is a combination of partial tongue resection and anterior suspension of the tongue (glossopexia). After glossopexia all the patients were subjectively relieved of their symptoms. However, polysomnography carried out postoperatively demonstrated that only 2 patients were objectively cured. The authors want to stress the necessity of meticulous polysomnographical registration pre- and postoperatively. Subjective and objective parameters recorded before and after surgery are discussed.

Sixty-seven patients, who were surgically treated for internal derangement of the temporomandibular joint (TMJ), were retrospectively examined. The patients were evaluated preoperatively by clinical and arthrographic examinations and these results were compared with findings at surgery. Partial or complete dislocation of the disc was detected by arthrographic examination in 65 joints. Actual disc displacement was demonstrated at surgery in 57 TMJs, giving arthrography a positive predictive value of 88% for detecting disc dislocation. Arthrographic diagnosis of disc perforation was unreliable, as both false positive and false negative observations were recorded. Arthrography was found to have a positive predictive value of only 53% for assessing disc perforation. Based upon its proven inaccuracy, invasiveness and discomfort to the patient, it is recommended to replace arthrography by magnetic resonance imaging.

Background: This study was undertaken to elucidate why large bilirubin loads cause canalicular cholestasis and whether bile acid infusions protect against bilirubin-induced cholestasis.Methods: The effects of bilirubin infusion on canalicular bile secretion and canalicular membrane morphology were studied in bile acid-depleted pigs (BADP), bile acid-primed pigs (BAPP), and pigs co-infused with bile acids during bilirubin loading (BACIP).Results: Bilirubin caused complete cholestasis in BADP, 38% bile flow reduction in BAPP, and no effect on bile flow in BACIP. Scanning electron micrographs showed loss of 70% of canalicular microvilli in BADP, 13% loss and pathologic changes in the remaining 75% of microvilli in BAPP, and no canalicular changes in BACIP. Cholestasis was not due to hydromechanical obstruction of bile ductules or bile Ca2+ depletion.Conclusion: Bilirubin causes cholestasis in BADP by injuring canalicular bicrovilli. Intravenous glycocholate infusions fully protect the liver against bilirubin-induced cholestasis and canalicular microvillar injury.

The importance of the blood coagulation sequence as an integral part in the pathogenesis of diseases inside as well as outside the blood vessels is becoming increasingly apparent. Mononuclear phagocytes have important functions in initiation of coagulation by producing several procoagulant substances, including thromboplastin, the potent trigger of the extrinsic pathway. Increasing evidence demonstrates the clinical importance of monocyte and macrophage thromboplastin synthesis in the pathogenesis of a variety of diseases. This review surveys the role of monocyte/macrophage thromboplastin in relation to inflammatory diseases, cancer, disseminated intravascular coagulation and diseases of the blood vessels, thrombosis and atherosclerosis.

Thromboplastin production in human monocytes gains steadily increasing significance as a pathogenetic factor in relation to human disease. A vast variety of stimuli can cause the induction of thromboplastin synthesis in monocytes, apparently through plasma membrane perturbation. Some of the possible signal compounds conveying information from the membrane to the intracellular-responding apparatus have been studied. Available data allow the conclusion that changes in intracellular concentrations of Ca2+, cyclic nucleotides and arachidonic acid metabolites as well as transmethylation reactions are of importance and modulate the integrated response which leads to increased synthesis and insertion of apoprotein III (the protein component of thromboplastin) in the plasma membrane.

Human monocytes isolated from peripheral blood responded with increased thromboplastin expression upon stimulation in vitro with three mycobacterial antigens: tuberculin purified protein derivative and sonicates of Mycobacterium boviS BCG and Mycobacterium leprae. The stimulating principle of mycobacteria is probably a cell wall constituent since crude extracts of cell walls were 2.5 to 25 times more potent in stimulating thromboplastin synthesis than were whole sonicates. This thromboplastin response was inhibited by inhibitors of RNA and protein synthesis, dexamethasone, and agents that caused elevation of intracellular cyclic AMP. The presence of lymphocytes did not enhance the monocyte thromboplastin response significantly during the first 24 h of incubation. For M. bovis BCG and M. leprae sonicates, the thromboplastin response correlated with general activating effects measured by determining the release of lysozyme and beta-glucuronidase. The role of thromboplastin in chronic inflammatory reactions is discussed.

A simple method is described for obtaining a large number of single smooth muscle cells by enzymatic digestion of heparin-perfused human umbilical cord arteries. The smooth muscle cell cultures exhibited the characteristic “hill and valley” growth pattern as seen by phase contrast and scanning electron microscopy. By using indirect immunofluorescence or alkaline phosphatase-anti-alkaline phosphatase techniques the cells were identified as smooth muscle cells by the presence of alpha smooth muscle actin and vimentin. The cultures were not contaminated by endothelial cells as demonstrated by the lack of von Willebrand factor immunoreactivity. This method makes it possible to study smooth muscle cells in primary cultures.

Purpose The effect of gonadotropins on implantation and fetal development in mice was investigated by superovulation with pregnant mare serum gonadotropin and human chorionic gonadotropin. In a previous study fetal growth was found to be highly retarded.

Differential cell counts and fibronectin levels were recorded in bronchoalveolar lavage fluids (BALF) from patients with lung cancer, idiopathic pulmonary fibrosis (IPF), sarcoidosis, pneumonia, acquired immunodeficiency syndrome (AIDS), and chronic obstructive lung disease (COLD). In all groups fibronectin levels were significantly higher than in the control group; patients with sarcoidosis had a six-fold higher fibronectin level (mean values), AIDS 5.4-fold, pneumonia 4.4-fold, lung cancer, IPF and COLD 2.4-3.0-fold. In control smokers the fibronectin level was significantly higher compared to healthy nonsmokers (p<0.002). The increased fibronectin levels could not be explained by contamination of BALF with blood or leakage of plasma proteins. Thus, increased fibronectin levels probably reflect local (e.g. macrophage/fibroblast) synthesis.

Changes in leukocyte subpopulations and the effects of high-dose corticosteroids (HDC) on these changes were studied in patients undergoing total hip replacement surgery. Twelve patients were randomly divided into a non-steroid (n=6) and a steroid group (n=6). The steroid patient group was treated with HDC. In the non-steroid group, we found a leukocytosis, monocytosis, lymphocytopenia and granulocytosis after surgery in local anaesthesia. Only the changes in granulocyte counts were significant. Furthermore, the relative proportion of pan T-cells, helper/inducer T-cells, suppressor/cytotoxic T-cells, B-cells, activated T-cells and natural killer-cell subset did not change significantly during the post-operative course. Thus, lymphocytopenia was caused by reduced absolute counts of all these subsets. However, there was a tendency for decreased relative proportions of pan T-cells, inducer/helper T-cells, activated T-cells and natural killer (NK) cell subset in the early postoperative phase.Treatment with HDC significantly raised the numbers of leukocytes and granulocytes and decreased the lymphocyte and monocyte counts in the first 2 days after surgery, accounting for significant differences between the two patients groups. The percentage of pan T-lymphocytes was significantly lower in the steroid patient group on days 1 and 2 after the operation. There was no significant difference between the two patient groups with regard to the percentages of B-lymphocytes, T-lymphocyte subsets, NK cell subset, leu M3 cells and helpensuppressor ratio. However, there was a tendency to decreased relative proportion of helper/inducer T-cells and activated T-cells as well as increased proportion of B-cells and NK subset cells in the immediate postoperative period. This combined with a more extensive lymphocytopenia in the steroid group, caused significantly lower absolute counts of pan T-cells, helper/inducer T-cells and suppressor/cytotoxic T-cells the first day after surgery compared with the non-steroid group.