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Biomedical subjects

A Bengtsson

Publications and source records attributed to A Bengtsson.

At least 55 records · Page 3Linked to original sources

Peripheral blood T-cell receptor beta-chain V-repertoire in atopic dermatitis patients after in vitro exposure to Pityrosporum orbiculare extract.

The yeast Pityrosporum orbiculare belongs to the normal cutaneous flora but is also considered to be one of the factors that may contribute to atopic dermatitis (AD). In the present study we investigated the possibility that P. orbiculare can act with superantigen activity in AD. P. orbiculare-reactive T-cell lines (TCLs) were obtained after stimulation of peripheral blood mononuclear cells (PBMC) with P. orbiculare extract. T-cell receptor beta-chain V-segment (TCRBV) usage was investigated using monoclonal antibodies and flow cytometry. We could not find any difference in TCRBV usage between AD patients (n = 10) and healthy controls (n = 5), either in fresh PBMC or in P. orbiculare-reactive TCLs. Compared with their original PBMCs the P. orbiculare-reactive TCLs showed a decreased usage of several TCRBVs, although increased usage of certain TCRBVs could be seen in some of the individuals. Further analysis of the CDR3-length polymorphism exhibited a shift in CDR3-length distribution, indicating oligoclonal expansion of T cells specific to different antigens in the P. orbiculare extract. In conclusion we have not found any evidence for superantigen activity in P. orbiculare extract, but our data support the importance of classical major histocompatibility complex (MHC)-restricted allergens in P. orbiculare.

Adolescent↗

Greater increase in cytokine concentration after salvage with filtered whole blood than with washed red cells, but no difference in postoperative hemoglobin recovery.

BACKGROUND: Inflammatory mediators are released in association with intraoperative and postoperative salvage of blood. Whether these mediators (cytokines) participate in the modulation of erythropoiesis or not has been investigated. STUDY DESIGN AND METHODS: Twenty-seven patients who were to undergo total knee replacement surgery were randomly assigned to postoperative blood salvage with either filtered whole blood or washed red cells. Patients with postoperative blood loss <400 mL were considered a control group. The control group did not receive any transfusions. Plasma concentrations of the anaphylatoxin C3a, the C5b-9 terminal complement complex, and the cytokines interleukins 6 and 8, hemoglobin, reticulocytes, and red cell volume fraction in the patients were repeatedly analyzed before and after surgery. RESULTS: Significantly increased concentrations of interleukin 6 appeared in all three groups, which was interpreted as a response to the surgical trauma. The increase was significantly greater in the group that received filtered whole blood after return of shed blood. The recovery of hemoglobin levels did not differ in the groups. CONCLUSION: The transfusion of filtered whole blood leads to the formation of interleukin 6 in the circulation, but postoperative hemoglobin recovery was similar in all groups.

Aged↗

[Comparative study of two methods for salvaging red blood cells: centrifugation techniques (cell-saver) versus filtration through a 100,000-dalton filter].

OBJECTIVES: Some loss of blood occurs during blood salvage. We hypothesized that plasmapheresis filtering would damage blood much less than centrifugation techniques do, thereby allowing more red blood cells to be transfused. MATERIAL AND METHODS: Laboratory study in which 16 units of whole donor blood were distributed randomly in two groups and processed either by a conventional "cell-saver" method or by hemofiltration using recirculation through a 100,000 dalton filter. We analysed hemoglobin, hematocrit, free hemoglobin, extracellular potassium, platelets, leukocytes, protein and albumin in whole blood before and after processing, and in the waste bag in each group. RESULTS: The recovery of hemoglobin and red blood cell volume was about 80% with both methods. More free plasma hemoglobin was found in the waste bag with the filtration technique. Hemolysis in processed blood was low, less than 0.1% in both groups. Platelet recovery with conventional centrifugation and filtration was 11 and 49%, respectively. Albumin, total protein and extra-cellular potassium were recovered at a rate of about 20% with the filtration technique, whereas recovery of these elements was minimal with the cell saver method. CONCLUSIONS: Both methods of autotransfusion caused moderate loss of red blood cells and low plasma levels of free hemoglobin in processed blood. Recovery of platelets, albumin, total protein and potassium was better with filtration than with the "cell-saver" method.

Blood Donors↗

Formation of complement split products and proinflammatory cytokines by reinfusion of shed autologous blood.

1. The purpose of this study was to determine whether shed autologous blood collected postoperatively contains complement split products (C3a and SC5b-9) and proinflammatory cytokines (TNF-alpha, IL-1beta, IL-6 and IL-8) and whether transfusion of shed blood increases the concentrations of inflammatory mediators in the circulation. 2. Twenty consecutive patients undergoing total hip replacement surgery under spinal anaesthesia were studied. The patients were transfused with whole blood collected postoperatively. 3. The median volume shed blood returned to the patients was 350 ml (25-75% range = 300-450). Before transfusion of shed blood was filtered using a 40 microm filter (Solcotrans). Samples for complement and cytokine determinations were drawn from the collected blood. 4. Venous blood samples were drawn 1 min before transfusion, 1 and 60 min after completed transfusion. High concentrations of C3a, SC5b-9, TNF-alpha, IL-1beta, IL-6 and IL-8 were found in shed blood. The concentrations were higher than the circulating levels (P < 0.05). The filtration procedure did not significantly reduce the concentrations. 5. Transfusion of the shed blood did not significantly alter the circulating concentrations of C3a, SC5b-9, TNF-alpha, IL-1beta, and IL-8. The plasma concentrations of IL-6 were increased both 1 and 60 min after completed transfusion compared to before (P < 0.05). 6. This study shows that whole blood collected from a surgical wound contains large concentrations of complement split products and proinflammatory cytokines. Transfusion of shed blood leads to elevated plasma levels of IL-6.

Aged↗

Sensitization to the major allergen of Brazil nut is correlated with the clinical expression of allergy.

BACKGROUND: Only a few studies have investigated the clinical role of food allergens, especially the relationship between sensitization to a given allergen and occurrence of adverse reactions when eating the relevant food item. OBJECTIVE: This study evaluated the clinical role of the allergens of Brazil nut by comparing the patterns of IgE binding in sera from 11 patients with anaphylaxis after eating Brazil nuts with those from 10 subjects with no symptoms to this food item. Both groups had specific IgE to Brazil nut. METHODS: Allergens in the in-house extract of Brazil nut were identified by SDS-PAGE/immunoblotting, the major allergen was purified by HPLC, and its N-terminal sequence was determined by a protein sequencer. RESULTS: SDS-PAGE/immunoblotting detected a number of allergenic components with molecular weights ranging from 4 to 58 kd. All sera from symptomatic patients recognized a 9-kd allergen corresponding (as established by amino acid sequencing) to a 2S albumin already described as a major allergen of Brazil nut, whereas the other allergens each bound IgE from less than 50% of sera. No sera from asymptomatic subjects showed IgE binding to the 9-kd allergen, but they did recognize components from 25 to 58 kd, which are minor allergens. CONCLUSIONS: These findings indicate that the allergen underlying clinical reactions to Brazil nut is a 2S albumin of 9 kd and that in vitro reactivity to this allergen identifies subjects who react in vivo to ingestion of this food.

2S Albumins, Plant↗

Pityrosporum orbiculare-reactive T-cell lines in atopic dermatitis patients and healthy individuals.

The yeast Pityrosporum orbiculare is one of the factors that may contribute to atopic dermatitis (AD). In the present study we compared the T-cell response to P. orbiculare in 12 AD patients with specific immunoglobulin (Ig)E antibodies (Ab) in serum against P. orbiculare with that of six non-atopic healthy controls. Freshly isolated peripheral blood mononuclear cells (PBMC) were cultured for 3 days in the presence of P. orbiculare extract. The proliferative response as measured by [3H]-thymidine incorporation was significantly higher in the AD patients than in the healthy controls (P < 0.05). Furthermore, significantly higher levels of interleukin (IL)-5 (P < 0.05), as analyzed by ELISA, were produced by PBMC from the AD patients compared to the healthy controls. Pityrosporum orbiculare-reactive T-cell lines (TCL) established by P. orbiculare stimulation of PBMC for 11 days produced significantly higher levels of IL-4 and IL-5 after stimulation with anti-CD3 Ab and showed a higher IL-4/interferon (IFN)-gamma ratio (P < 0.05) in the AD patients compared to the healthy controls. The higher proliferative PBMC response to P. orbiculare and the Th2-like cytokine production by P. orbiculare-stimulated TCL from AD patients indicate that P. orbiculare may play a role in maintaining skin inflammation in AD.

Adolescent↗

Anti-TNF treatment of baboons with sepsis reduces TNF-alpha, IL-6 and IL-8, but not the degree of complement activation.

The activation of complement and the release of TNF-alpha, IL-6 and IL-8 are important pathogenic factors behind organ dysfunction in sepsis. The aim of this study was to determine whether infusion of anti-TNF antibodies alters complement activation and plasma concentrations of pro-inflammatory cytokines at high doses of Escherichia coli. Six baboons received intravenously 2 x 10(9) live E. coli bacteria per kg body weight (group 1), in addition five received pretreatment with 1 mg per kg body weight anti-TNF antibodies (group 2), and seven received 5 x 10(8) live E. coli bacteria per kg body weight (group 3). Two hours after the start of infusion of the bacteria, plasma concentrations of C3 activation products, C5a and the terminal SC5b-9 complement complex were increased in groups 1 and 2 (P < 0.05), but there was no significant difference between the groups. At 2 h the levels of TNF-alpha, IL-6 and IL-8 were lower in group 2 compared with group 1 (P<0.05). In group 2 compared with group 1 the TNF-alpha concentrations were, however, higher at 4, 8 and 24 h. The explanation for this phenomenon is probably that TNF-alpha binds to the anti-TNF antibody complex and is released slowly after it has been bound. The study showed that infusion of anti-TNF antibodies reduced the concentrations of TNF-alpha, IL-6 and IL-8, without any detectable influence on complement activation.

Animals↗

Effects of intravenous regional administration of methylprednisolone plus mepivacaine in rheumatoid arthritis.

To evaluate the subjective and objective response to intravenous regional administration of a glucocorticoid (IVRAG) on rheumatoid arthritis (RA), twenty RA-patients received, in a randomised, double-blind crossover and placebo-controlled fashion, either 50 mg methylprednisolone in mepivacaine 0.25% or mepivacaine (placebo) in one hand only using a Bier-block technique. The other hand was given the opposite. One week later the procedure was repeated but the previous placebo hand was now treated with the glucocorticoid. About 50% of the patients experienced a subjective improvement at 1 and 6 weeks. After one week a significant reduction was recorded in grip diastasis with no difference between the glucocorticoid and the placebo. In the other outcome measures (grip strength, handvolume, rest pain, and movement provoked pain) no differences were recorded between the glucocorticoid and placebo. At six weeks a significant reduction in grip diastasis and movement provoked pain as well as a significant increase in grip strength were noted. Hand volume was unchanged. IVRAG is a safe, easy and well-tolerated technique. The beneficial results are probably due to both a systemic and a regional effect. The findings of benefit in both hands at the end of one week seem to suggest that mepivacaine can give some short term improvement.

Adult↗

Extracorporeal ("ex vivo") connection of pig kidneys to humans. III. Studies of plasma complement activation and complement deposition in the kidney tissue.

The complement system is one of the important factors involved in the hyperacute rejection of xenografts. This report deals with the activation of the complement system in a clinical trial where pig kidneys were extracorporeally connected to two volunteer dialysis patients who were pretreated with plasmapheresis in order to substantially reduce anti-pig xenoantibodies. The clinical data of the perfusion experiments and the patients humoral immune response to pig xenoantigens have been reported in detail (Xenotransplantation 1996; 3:328-339, 340-353). Three consecutive daily plasmapheresis treatments of the patients reduced the plasma complement protein (C3, C4, and C5) concentrations to 8-27% of the baseline values. The perfusion of the pig kidney connected to patient 1 was terminated at 65 min due to graft rejection and this patient was not hemodynamically affected by the experiment. The second experiment was terminated at 15 min due to an anaphylactic like reaction of the patient. In patient 1 a slight reduction of plasma C3, C4, and C5 and an increase of C5a and SC5b-9 occurred, while C3a decreased during the perfusion. Patient 2 had an increase of all complement parameters, most prominent for C4d and SC5b-9, which occurred concomitant with the appearance of the anaphylactic like side effects. In general, plasma levels of PMN elastase, IL6 and IL8 increased in both patients during the perfusion. Immunohistochemical investigation of the kidney tissues revealed deposition of human complement factors C1q, C4c, and C3c in a congruent pattern with the vasculature of the kidney in patient 1. In kidney 2 only trace amounts of C1q and C3c were found. Both kidneys were negative for properdin. Therefore, in this experimental set up with extracorporeal connection of pig kidneys to the human circulation the human complement cascade is activated mainly through the classical pathway.

Adult↗

Respiration during emergence from anaesthesia with desflurane/N2O vs. desflurane/air for gynaecological laparoscopy.

BACKGROUND: The complications related to anaesthesia usually occur in the early postoperative period. Hypercapnia and hypoxaemia may result from any persistent depression of the respiratory drive relative to the metabolic demand. The purpose of this study was to compare the respiratory effects of desflurane anaesthesia with or without nitrous oxide during the period of emergence. METHODS: Twenty patients scheduled for a standardised surgical procedure, laparoscopic hysterectomy, were randomly allocated to anaesthesia with 1.3 MAC of desflurane/N2O (Group 1) or desflurane alone (Group 2), with 10 patients in each group. Times of resumption of spontaneous breathing and extubation were recorded and elimination rates of carbon dioxide, end-tidal concentrations of desflurane and N2O, and blood gases were measured. RESULTS: Spontaneous breathing was resumed in both groups when pH had decreased by about 0.07 and PaCO2 increased by about 1.4 kPa compared with the values at the end of 1.3 MAC anaesthesia with controlled normoventilation. There were no significant differences between the groups with regards to extubation time, 6 vs. 13 min, or total MAC value at extubation, 0.20 vs. 0.19 in Group 1 and 2, respectively. Neither did the groups differ in minute ventilation, end-tidal carbon dioxide, oxygen concentrations, or blood gases. CO2 elimination decreased in both groups from about 220 ml 70 kg-1 min-1 at the end of anaesthesia to a lowest value of about 160 ml 70 kg-1 min-1. CONCLUSION: The respiratory profiles during recovery from gynaecological laparoscopy with either desflurane/N2O or desflurane anaesthesia were similar with fast resumption of spontaneous breathing, short time to extubation, and no signs of CO2 retention.

Adult↗

Removal of activated complement from shed blood: comparison of high- and low-dilutional haemofiltration.

BACKGROUND: Perioperative blood salvage is associated with release of inflammatory mediators. Depending on type of processing, the complement system is activated to some extent in the final blood product. The aim of the present study was to evaluate a haemofiltration technique concerning complement system activation and whether the volume of added saline will have an influence on the elimination of activated complement during processing. METHODS: Sixteen patients undergoing total hip arthroplasty received wound blood salvaged intraoperatively with a haemofiltration technique. Saline was added to the reservoir for washing in a ratio of 1:1 or 5:1 of estimated blood volume. Samples for determination of the anaphylatoxins C3a and C5a, and the terminal SC5b-9 complement complex (TCC) were drawn from the patients, the collected blood, the ultrafiltrate and the processed blood. RESULTS: Increased concentrations of C3a, C5a and TCC were found in aspirated and processed blood. Haemofiltration did not reduce the concentrations of these factors, except that of C3a in the group where saline was added in a ratio of 5:1. There were no increased concentrations of C3a, C5a or TCC in the patient plasma after reinfusion. No differences in blood pressure, heart rate, pH, arterial oxygen tension, arterial carbon dioxide tension, or base excess were found in association with reinfusion of the blood. CONCLUSION: Collected shed blood washed through haemofiltration contained moderately elevated concentrations of C3a, C5a and TCC. Reinfusion of the blood neither led to increased systemic concentrations of complement activation products, nor to disturbances in haemodynamic or biochemical parameters.

Acid-Base Equilibrium↗

Pain and pulmonary function following laparoscopic and abdominal hysterectomy: a randomized study.

BACKGROUND: The aim of this study was to evaluate pain and pulmonary function the first two days after abdominal and laparoscopic hysterectomy. METHODS: Women scheduled for abdominal hysterectomy were prospectively randomized to either laparoscopic (n=20) or abdominal (n=20) hysterectomy. Analgesics were self-administered by the patients by means of a programable infusion pump containing morphine. Postoperative pain was evaluated using a visual analog scale. Oxygen saturation was measured with an oxymeter. Pulmonary function was assessed using a peak flow meter measuring peak expiratory flow and a vitalograph measuring forced vital capacity and forced expiratory volume in one second. RESULTS: Pain scores were lower after laparoscopic hysterectomy at the first (p<0.05) and second postoperative day (p<0.01). Lung function was impaired on days 1 and 2 postoperatively, measured as peak expiratory flow, forced vital capacity and forced expiratory volume in one second, in both groups compared to the preoperative values. The patients undergoing laparoscopic hysterectomy had less impairment of lung function measured by peak expiratory flow (p<0.01), forced vital capacity (p<0.05) and forced expiratory volume in one second (p<0.05) the first postoperative day compared to the patients undergoing abdominal hysterectomy. The second postoperative day differences between the groups remained for peak expiratory flow (p<0.05) and forced expiratory volume in one second (p<0.05). CONCLUSIONS: Laparoscopic hysterectomy results in less pain and less impairment of respiratory function compared to abdominal hysterectomy.

Female↗

Elevated serum levels of soluble CD30 in patients with atopic dermatitis (AD).

The immunopathology of AD is still unclear, but evidence for an immune response polarized towards Th2 activity has been provided. The CD30 molecule belongs to the tumour necrosis factor (TNF) receptor family and is expressed on activated T cells with a sustained expression in Th2 cells. This molecule also exists in a soluble form (sCD30). Elevated serum levels of sCD30 have been found in patients with Hodgkin's disease, chronic hepatitis B infection and HIV infection. Studies were undertaken to compare the serum levels of sCD30 in patients with AD (n=49) and healthy non-atopic controls (n=94). The presence of sCD30 was analysed with ELISA. A significantly higher concentration of sCD30 was noted in AD patients, median sCD30 level 29 U/ml (range 1-708 U/ml), compared with healthy non-atopic controls (P<0.001), where the median level was 11 U/ml with a range of 1-1042 U/ml. No correlation was found between sCD30 levels and total serum IgE, or between the AD patients' SCORAD values and concentration of sCD30. sCD30 levels were also analysed in 20 AD patients, which during ketoconazole treatment had improved their clinical scores and reduced their serum IgE and eosinophil cationic protein levels. However, no significant decrease in sCD30 levels was noted after treatment. The results show that patients with AD have elevated levels of sCD30, but without correlation to total serum IgE or disease activity.

Adolescent↗

Blood spillage during salvage.

Recovery of blood components by salvage was evaluated in a randomized laboratory investigation using donor whole blood. Three methods of salvage were studied; conventional red cell salvage, red cell salvage with continuous processing, and salvage by haemofiltration using recirculation through a 30,000-Da filter. Less than 10% of the haemoglobin was wasted during processing by all three methods. About half of the leukocytes were recovered with no significant difference between the techniques. The recovery of platelets was 15, 4 and 41% during salvage with conventional red cell centrifugation, continuous centrifugation processing and haemofiltration, respectively. In contrast with the other methods, haemofiltration gave a major recovery of albumin.

Blood Cell Count↗

Effects on complement activation of a new continuous autotransfusion system.

Allogeneic blood transfusions may subject patients to risks of infection and allergic reactions. Various techniques for transfusion of shed blood have been developed. The aim of this study was to evaluate a new continuous autotransfusion system (Fresenius CATS) as regards its impact on the complement system, and on erythrocytes and leucocytes. Eighteen consecutive patients undergoing hip replacement surgery were studied. Complement variables (C4d, factor Bb, C3a and terminal complement complex, SC5b-9) and free haemoglobin, haemoglobin, leucocytes, platelets, albumin and protein were determined in the patient's blood preoperatively, 1 min before the start of transfusion, 15 and 60 min after transfusion; and in the reservoir, in the waste bag and in the retransfusion blood. Increased concentrations of C3a and SC5b-9 were found in the collected reservoir blood (P < 0.05). The washing and centrifugation procedure reduced these concentrations (< 0.001). High levels of free haemoglobin were found in the collected blood as well as in the processed product. The median haemoglobin level in the processed blood was 260gL-1 (range 104-289gL-1). Inflammatory mediators from the complement cascade are removed by continuous autotransfusion technique. The processed blood contains high levels of free haemoglobin.

Adult↗

Complement activation during storage of whole blood, red cells, plasma, and buffy coat.

BACKGROUND: The process of separating whole blood into components and the storage of blood components may cause the release of toxic metabolites from the complement cascade. The aim of this study was to determine whether the storage of blood components leads to the activation of the complement cascade and the release of anaphylatoxins. STUDY DESIGN AND METHODS: Blood from 12 healthy volunteers was collected and stored either as whole blood or as components: red cells in saline-adenine-glucose-mannitol solution, plasma, and buffy coat. The concentrations of anaphylatoxins and other complement proteins in the various blood components were intermittently analyzed during a 5-week storage period. RESULTS: Increasing levels of anaphylatoxins were demonstrated during the storage of whole blood and plasma. Elevated concentrations of the anaphylatoxins C3a and C5a were observed during the storage of whole blood. Increased C5a levels were observed after 7 days of storage. High concentrations of C3a were found in plasma after 14 days of storage. Low or non-detectable levels of C3a; C5a, and other complement components were found in red cells stores in saline-adenine-glucose-mannitol solution. CONCLUSION: The study demonstrated activation of complement during the storage of whole blood and plasma but not in red cells in storage solution. The transfusion of larger volumes of stored whole blood or plasma may contribute to the risk of development of organ dysfunction. Therefore, it is advisable to use red cells in storage solution.

Anaphylatoxins↗