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Biomedical subjects

M Bengtsson

Publications and source records attributed to M Bengtsson.

At least 109 records · Page 6Linked to original sources
PubMed1989

Epidural morphine by the thoracic or lumbar routes in cholecystectomy. Effect on postoperative pain and respiratory variables.

Thirty-seven women undergoing elective cholecystectomy were randomised into two groups, receiving either lumbar epidural morphine (group L) or epidural morphine via the thoracic route (group T). The effect on pain relief was assessed by a visual analogue scale and included both resting pain and 'provoked' pain. Respiratory parameters (PEF, FEVI and FVC) were also studied. The patients were investigated preoperatively, and 4, 6, 12 and 24 hours after the start of surgery. No significant difference was observed between the groups concerning pain relief or respiratory performance. We conclude that after cholecystectomy lumbar epidural morphine is as effective as thoracic epidural morphine in relieving postoperative pain.

Adult↗
PubMed1989

B-cell reconstitution after autologous bone marrow transplantation: increase in serum CD23 ("IgE-binding factor") precedes IgE and B-cell regeneration.

The serum levels of IgE and the soluble cleavage product of CD23 (sCD23) were prospectively monitored for up to 1 year after transplantation in 34 patients who underwent autologous (n = 33) or syngeneic (n = 1) bone marrow transplantation (BMT). In 25 patients (74%), a transient IgE peak (two- to 2,750-fold increase) appeared in the serum 3 to 4 weeks after BMT. In 18 patients (51%), a two- to 125-fold increase in sCD23 coincided with the IgE peak. In only three patients was a sCD23 peak observed without a concomitant increase in IgE. The sCD23 increment preceded the IgE peak in each individual case. During the period of increased sCD23 serum levels, the absolute numbers of circulating B cells and other cell types expressing surface CD23 were extremely low. The biologic significance of these findings is discussed in light of present knowledge of regulation of B-cell growth and differentiation with special reference to the role of sCD23 as a multifunctional cytokine.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1989

Regeneration of functional and activated NK and T sub-subset cells in the marrow and blood after autologous bone marrow transplantation: a prospective phenotypic study with 2/3-color FACS analysis.

The phenotypic reconstitution of lymphoid cells in the bone marrow and peripheral blood was examined prospectively in 27 patients who underwent autologous bone marrow transplantation (ABMT) for leukemia/lymphoma. Patterns of activation within NK and T cell subsets as well as T sub-subsets were studied with monoclonal antibodies in two- and three-color FACS analysis. NK-like cells (CD16+) were found to be increased in the peripheral blood and bone marrow after ABMT. The expression of two activation markers, 4F2 and HLA-DR, was sustainedly increased within this subset. High numbers of CD4+ and CD8+ T cells carrying surface HLA-DR were found early after ABMT both in blood and marrow. The T suppressor inducer cell sub-subset (CD45R+ CD4+) was severely depressed in both the blood and marrow 6-9 months post-ABMT. Using three-color FACS analysis, half of this T sub-subset was shown to express HLA-DR+. The levels of T suppressor effector-like cells (CD11+ CD8+) remained within the normal range in both peripheral blood and bone marrow during follow-up. The HLA-DR expression was elevated and equally distributed between the CD11- CD8+ and CD11+ CD8+ sub-subset cells. There was no major impact of marrow T cell purging or CMV carrier status on the phenotypic NK/T cell reconstitution. The present results provide an immune phenotypic basis for the suggested generation of anti-leukemic NK-like and T suppressor-like activity after ABMT.

Adolescent↗
PubMed1988

Regional sympathetic blockade in primary fibromyalgia.

Twenty-eight patients with primary fibromyalgia participated in the study. Eight patients received a stellate ganglion blockade with bupivacaine, and 14 days later an intravenous regional sympathetic blockade with guanethidine. The remaining patients served as controls and were randomly allocated to receive either a sham (placebo) injection with physiologic saline superficial to the stellate ganglion (n = 10) or bupivacaine intramuscularly (n = 10). The efficiency of the stellate ganglion blockade was evaluated by measuring skin blood flow (using a laser Doppler flowmeter), skin temperature, and skin conductance responses ('sympathogalvanic reflex'). Trigger and tender points (TePs) were counted, and rest pain in the arm, shoulder and neck evaluated at intervals up to 4 h after the injection. The guanethidine blockade was evaluated 24 h after the injection by counting TePs and by assessment of rest pain in the hand and forearm. The results indicate that a complete sympathetic blockade, produced by a stellate ganglion blockade, markedly reduced the number of TePs and produced a marked decrease in rest pain. The guanethidine blockade reduced the number of TePs, but had no effect on rest pain. The reduction in pain and TePs produced by a sympathetic blockade may be due to an improvement in microcirculation. Sympathetic activity may, in some patients, contribute to the pathogenesis of primary fibromyalgia.

Adult↗
PubMed1988

Skeletal muscle function in primary fibromyalgia. Effect of regional sympathetic blockade with guanethidine.

Muscle fatigue is the most disabling symptom in primary fibromyalgia (PF), which in addition is characterized by generalised pain and muscle stiffness. In order to assess whether the fatigue is of central and/or peripheral origin, skeletal muscle function was studied by measuring maximum voluntary hand grip strength, and by measuring various contraction characteristics in the adductor pollicis muscle after electrical stimulation of the ulnar nerve. The PF-patients were also studied after a regional sympathetic blockade of the forearm with guanethidine. A lower hand grip strength was found in the PF-patients compared to the controls, before as well as during the sympathetic blockade. The developed force, measured during electrical stimulation, did not differ between patients and controls. A lower muscle relaxation rate was found in the PF-patients. The relaxation rate increased in the PF-patients during the sympathetic blockade. The results indicate both a central and a peripheral cause of muscle dysfunction. Activity in the muscle sympathetic system may be one link in the chain of events that leads to muscular symptoms in PF.

Action Potentials↗
PubMed1988

Treatment of pure red cell aplasia with ciclosporin: suppression of activated T suppressor/cytotoxic and NK-like cells in marrow and blood correlates with haematological response.

In pure red cell aplasia (PRCA), suppression of erythropoiesis is most probably effected by cellular and/or antibody-mediated immune mechanisms. We have prospectively investigated the patterns of activated T-lymphocyte subsets and natural killer (NK)-like cells in the bone marrow (BM) and peripheral blood (PB) of 6 PRCA patients prior to and during treatment with the T-cell selective immunosuppressive drug Ciclosporin (CS; Cyclosporin-A). Before CS therapy, large proportions of circulating activated HLA-DR+ T-suppressor/cytotoxic cells (28%, 11-41; median and range), DR+ T-helper cells (7%, 4-13) and cytoplasmic interferon-gamma+ (IFN-gamma) lymphocytes (20%, 9-33) were found in PRCA, but were barely detectable in healthy controls. Similarly, high levels of activated T cells were present in patient marrows. Initiation of CS therapy resulted in rapidly decreasing levels of activated T cells and NK cells both in PB and in BM. During follow-up of individual patients, an inverse relationship was observed between the haematological response to CS and the levels of activated T-suppressor/cytotoxic cells, IFN-gamma+ lymphocytes (in PB and BM) and NK-like cells (in BM). The present correlations indicate a pathogenetic role of phenotypically activated T-suppressor/cytotoxic cells and possibly NK-like cells in PRCA. During successful treatment with CS, these cell types are reduced in numbers but reappear in relapse. Our results also pinpoint the clinical value of monitoring activated T-cell subsets for the prediction of immunological remission in PRCA and related disorders.

Adult↗
PubMed1988

Metabolism of 7,12-dimethylbenz(a)anthracene by different types of cells in the human ovary.

1. The metabolism of 7,12-dimethylbenz(a)anthracene (DMBA) by primary cultures of human ovarian cells has been studied to identify the cell type(s) responsible for biotransformation of this carcinogen. The rate of DMBA metabolism was maximal in granulosa cells prestimulated in vivo with antiestrogen, hMG (human menopausal gonadotropin) and hCG (human chorionic gonadotropin), i.e., treatments required for maximal oocyte maturation and, thus, granulosa cell proliferation. In cells from unstimulated ovaries, the metabolism was maximal in granulosa-lutein cells isolated from corpus luteum. 2. Steroid (progesterone and estradiol) levels were determined in the spent culture media or in media in parallel with DMBA metabolism to find out whether elevated steroid levels in vivo are required for the rapid metabolism of DMBA. In granulosa cell cultures from stimulated cycles, the concentrations of both progesterone and estradiol were at least 2 or 3 times higher, respectively, than in any of the other cell types tested. In cell cultures derived from unstimulated ovaries, the progesterone and estradiol concentrations were highest in granulosa-lutein cell cultures. 3. Incubations of granulosa cells with DMBA in the absence or presence of gonadotropins, testosterone or anti--hCG were performed to investigate possible hormonal requirements for the cytochrome P-450 system(s) which metabolize DMBA. No change in the rate of metabolism was obtained with follicle stimulating hormone (FSH), luteinizing hormone (LH), hCG or testosterone. However, anti-hCG increased this activity about 70%, indicating a negative modulatory role of hCG on DMBA mono-oxygenase activity in human granulosa cells. 4. DMBA mono-oxygenase activity in cell cultures was inhibited about 95% by alpha-naphthoflavone (ANF), an inhibitor of certain cytochrome P-450-catalysed activities. Benzo(a)pyrene (BP) was metabolized at the same rate as DMBA in granulosa cell cultures.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1988

Changes in skin perfusion after sympathetic block with guanethidine. Laser Doppler flowmetry in human volunteers.

Total forearm blood flow and skin microcirculation have been measured by occlusion plethysmography and by laser Doppler flowmetry (skin blood cell flux) before and after the induction of regional sympathetic block with Guanethidine. Total forearm blood flow more than doubled while the skin blood cell flux increased by 50% comparing simultaneous flows of blocked and control arms. The increase lasted for 3 days during which period the flux pattern registered by the laser Doppler flowmeter in the blocked extremities showed regular variations oscillating around the mean flux in an almost sinus wave fashion. In non-blocked arms the flux pattern registered by the laser Doppler flowmeter was highly irregular. We conclude that regional sympathetic block with Guanethidine results in an increased skin microcirculation in healthy human volunteers and that the increase lasts for 3 days. No valid conclusions can be made from this study concerning the nutritive benefit of the microcirculatory change.

Adult↗
PubMed1988

Spinal haematoma following epidural analgesia. Report of a patient with ankylosing spondylitis and a bleeding diathesis.

A patient who developed an epidural haematoma with multifactorial aetiology (bleeding diathesis, ankylosing spondylitis, chronic alcoholism and acute pancreatitis) after epidural analgesia for pain relief is described. Our conclusion is that adequate laboratory screening of blood coagulation, including platelet count, should be carried out in this category of patient before attempted epidural blockade, the risks of which must be weighed against the benefits. The block should be allowed to wear off intermittently and repeated neurological assessment performed if an epidural catheter is used for repeated injections or for a continuous infusion of local anaesthetic. Neuroradiological examination should be carried out promptly if an epidural haematoma is suspected and surgical decompression performed without delay if the diagnosis is confirmed.

Anesthesia, Epidural↗
PubMed1987

Induction of circulating activated suppressor-like T cells by methimazole therapy for Graves' disease.

Thyrostatic drug treatment of Graves' disease suppresses excessive thyroid hormone synthesis and causes a parallel decrease in serum thyroid autoantibody levels. The mechanism of this immunosuppression is unknown. We studied methimazole-induced immunoregulatory effects prospectively in 14 patients with Graves' disease treated for up to six months. The numbers of circulating activated, HLA-DR-positive T helper/inducer cells decreased gradually, from 8.3+1.7 percent (+SD) to 1.0+1.7 percent (P less than 0.001). HLA-DR-positive T suppressor/cytotoxic cells increased transiently at one month, from 2.0+1.9 percent to 12.6+6.4 percent (P less than 0.001), and returned to 2.9+3.7 percent at six months. Methimazole did not alter the HLA-DR expression of T cells in vitro. In two patients, the helper activity of T cells in inducing autoantibody secretion in vitro was substantially reduced after one month of methimazole treatment. Before treatment, large proportions of thyroid-infiltrating T-cell subsets expressed the activation markers HLA-DR, interferon-gamma, and interleukin-2 receptors, which were partially lost during therapy. Methimazole treatment was accompanied by a gradual reduction in circulating levels of thyrotropin-receptor, microsomal, and thyroglobulin autoantibodies. These results are compatible with the view that methimazole-induced immunoregulation in Graves' disease is mediated by a direct inhibitory effect on thyrocytes. This inhibition is in turn accompanied by marked changes in the proportions of activated T helper-like and T suppressor-like cells. This altered T-cell activation profile reflects, at least in part, the functional suppression of autoantibody production observed in methimazole-treated patients with Graves' disease.

Adult↗
PubMed1987

Mechanisms of regulation of rat ovarian 7,12-dimethylbenz[a]anthracene hydroxylase.

The mechanisms of regulation of ovarian 7,12-dimethylbenz[a]anthracene (DMBA) hydroxylase were investigated with respect to hormonal requirements and effects of the antiestrogen tamoxifen and known inducers of cytochrome P-450. The DMBA hydroxylase is increased endogenously about 3-fold in the proestrus phase as compared to the metestrus/diestrus phases (M. Bengtsson and J. Rydstrom, Science, 219 (1983) 1437-1438). A similar effect was caused by the gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone (LH) whereas pregnant mare's serum gonadotropin (PMSG) brought about a 3-7-fold increase, suggesting that the estrus cycle-dependence of the DMBA hydroxylase was due directly or indirectly to gonadotropins. In contrast, differentiation of granulosa/theca cells to corpus luteum cells after ovulation, caused by administration of human chorionic gonadotropin (hCG), led to a marked decrease in activity. The activity was not specific for DMBA since substitution of this hydrocarbon for benzo[a]pyrene (BP) as substrate gave similar results. A possible role of estrogens in this context was investigated by the administration of tamoxifen simultaneous with gonadotropin treatment, which caused a partial inhibition of the hydroxylase activity. Both estradiol and 3-methyl-cholanthrene (MC) increased DMBA hydroxylase but the effects of these agents were not additive. In contrast, the effects of estradiol and MC were partially additive to that of gonadotropin. On the basis of these results, it is proposed that the rat ovary contains one or several aryl hydrocarbon hydroxylases located in the granulosa/theca cells which are regulated by estrogens, MC and beta-naphthoflavone (BNF) and that the role of gonadotropins is to proliferate granulosa/theca cells.

Animals↗
PubMed1987

Sympathetic activity and haemodynamic variables during spinal analgesia in man.

At present there is a lack of information concerning haemodynamic changes related to the degree of sympathetic blockade during spinal analgesia. In this investigation, involving 36 patients, changes in haemodynamic parameters were studied in 30 patients receiving spinal analgesia and in six patients having "sham spinal" analgesia. Three local anaesthetic solutions were used: bupivacaine without and with glucose and tetracaine with glucose. Skin conductance responses were used to evaluate changes in provoked sympathetic activity. It was found, as in previous studies, that a complete block of sympathetic activity in the foot was seen in only 60% of patients with an average analgesic level of T4. A partial sympathetic blockade was registered up to and above the level of analgesia. In 25/30 cases only minor alterations in cardiac output, heart rate, stroke volume, mean arterial pressure and systemic vascular resistance were seen in spinal analgesia whose level reached on average T4-5. In five cases in whom analgesia reached T4-3, mean arterial pressure fell greater than or equal to 30% with a well-preserved cardiac output, but with complete sympathetic blockade up to T5 and in two cases also in the hand. Only minor differences were observed between the different anaesthetic solutions.

Analgesia↗
PubMed1987

High-energy phosphates and surface oxygen pressure fields in skeletal muscle after high-energy trauma.

The effect of a high energy missile trauma on energy metabolism and tissue oxygenation in uninjured parts of skeletal muscle was studied in anaesthetized pigs up to 72 hours after the trauma. High energy phosphates (HEP) were measured in muscle biopsies, and muscle tissue oxygenation was measured as muscle surface oxygen pressure fields by an oxygen electrode. In the traumatized group significantly decreased levels of HEP were found in spite of normal tissue oxygenation 72 hours after the trauma. In the control group both the HEP and the muscle tissue oxygenation were unchanged compared to the pretrauma situation. Decreased synthesis of HEP due to tissue hypoxia or inadequate nutrition could not account for the difference between the control and the trauma group. It was suggested that hypermetabolism induced by the high energy trauma caused increased utilization and thereby decreased concentrations of the HEP 72 hours after the trauma. It was also concluded that the general posttraumatic metabolic changes found in uninjured parts of the muscle tissue differed from the local changes of traumatized muscle described by other investigators, and therefore probably were caused by other mechanisms.

Adenosine Diphosphate↗
PubMed1986

Visual disturbances after industrial triethylamine exposure.

Among 19 workers in a polyurethane foam production plant, visual disturbances ("foggy vision", "blue haze", and sometimes halo phenomena) were reported on a total of 47 occasions by five workers over 11 weeks. The symptoms were associated with triethylamine exposure. Time-weighted average levels of 12 to 13 mg/m3 were recorded at work operations associated with symptoms, and 4 to 5 mg/m3 at other tasks. Twice as high peak levels were recorded. A detailed medical examination of the five affected workers in a free interval did not reveal any signs of permanent eye disease.

Adult↗
PubMed1986

A study of halothane-diethyl ether azeotrope and the Oxford miniature vaporizer.

The performances of an Oxford miniature vaporizer (OMV) and a Fluotec Mark III vaporizer filled with an azeotropic mixture of halothane and diethyl ether were studied. Gas concentrations were estimated using an EMMA gas analyser and a MIRAN spectrophotometer. Calibration tables for both vaporizers were derived. In a small clinical series with air as the carrier gas, to which a small amount of oxygen was added, the azeotrope was found to be a satisfactory anaesthetic agent, giving a short awakening time and an almost pain-free postoperative course.

Anesthesia, Inhalation↗