PubMed HealthSearch

Biomedical subjects

S Jacobsen

Publications and source records attributed to S Jacobsen.

At least 19 recordsLinked to original sources

Antifungal activity of chitin-binding PR-4 type proteins from barley grain and stressed leaf.

Antifungal activity in vitro has been associated with barley leaf and grain proteins which are homologous with pathogenesis related proteins of type 4 (PR-4) from tobacco and tomato and with C terminal domains of potato win and Hevea hevein precursor proteins. One protein (pI approximately 9.3, M(r) approximately 13.7 kDa) from barley grain and two very similar proteins from leaves infected with Erysiphe graminis were isolated by chitin affinity chromatography, but none of the proteins showed chitinase activity in vitro. The leaf proteins were increased several fold in response to either Erysiphe infection or NiCl2 infiltration and accumulated extracellularly. The three barley proteins were found to inhibit growth of Trichoderma harzianum in microtiter plate assays using approximately 10 micrograms/ml concentrations and in lower concentrations in a synergistic way when mixed either with barley chitinase C (a PR-3 type protein) or with barley protein R (a PR-5 type protein). Structurally similar proteins were detected in wheat, rye and oats grain extracts.

Amino Acid Sequence

31P magnetic resonance spectroscopy of skeletal muscle in patients with fibromyalgia.

31Phosphorous nuclear magnetic resonance (31P NMR) spectroscopy of painful calf muscle was performed in 12 patients with fibromyalgia (FS) and 7 healthy subjects during rest, aerobic and anaerobic exercising conditions, and postexercise recovery. Ratios of inorganic phosphate and creatinine phosphate (Pi/PCr) and pH were calculated from the collected 31P NMR spectra. Resting values of Pi/PCr were normal in the patients. Patients delivered only 49% of the muscle power of the controls (p = 0.005). Patients and controls had similar rates of Pi/PCr and pH changes during work and recovery. The controls were able to change their Pi/PCr and pH more than the patients, due to the greater workload reached. However, statistical significance was reached only for the anaerobic static exercise (p = 0.003). It was concluded that patients with FS have a reduced voluntary capacity for work, but normal biochemical response to work and recovery.

Adult

Dynamic muscular endurance in primary fibromyalgia compared with chronic myofascial pain syndrome.

The objective of the study was to quantify the voluntary dynamic muscular endurance (DME) in patients with primary fibromyalgia (PF) since easy fatigability of muscles is one of the major symptoms in this syndrome. Consecutive outpatients referred to a rheumatology clinic specializing in PF were investigated. Thirty-six patients with PF were compared with 18 patients with chronic myofascial pain (CMP) syndrome. Subjects were matched according to gender, age, height, weight, peak torque, and contractional work. The DME was defined as the number of repeated knee extensions necessary for the contractional work in two successive knee extensions to be equal to or below 70% of the initial value measured with an isokinetic dynamometer. A significantly lower DME was found in the PF group than in the CMP group: 11 (7-13) and 18 (11-25), respectively (median and quartiles), p less than .005. Patients with PF have a low voluntary muscular endurance compared to CMP patients.

Activities of Daily Living

Two antifungal thaumatin-like proteins from barley grain.

Antifungal activity has been associated with 2 immunochemically distinct proteins, protein R and S (Mr approximately 23 kDa; pI 9-10), which were isolated in pure form from barley grain. The proteins are homologous with thaumatin- and pathogenesis-related proteins of the PR5 family. The proteins inhibit growth of i.a. Trichoderma viride and Candida albicans in microtiter plate assays and act synergistically with barley grain chitinase C. Like maize zeamatin, protein R and S but not chitinase C retarded fungal growth in synergism with nikkomycin Z, a nucleoside-peptide inhibitor of fungal chitin synthesis. Although no inhibition of alpha-amylases or serine proteases could be associated with protein R or S the results indicate that the homologous maize grain bifunctional inhibitor of insect alpha-amylase and trypsin is very similar to or identical with maize zeamatin, which was proposed to have permeabilizing activity towards fungal membranes. Thus, in addition to the intensely sweet properties of thaumatin, multiple unrelated defense functions against insect and fungal pests can now be associated with the family of thaumatin-homologous proteins.

Amino Acid Sequence

Oral S-adenosylmethionine in primary fibromyalgia. Double-blind clinical evaluation.

S-adenosylmethionine is a relatively new anti-inflammatory drug with analgesic and anti-depressant effects. Efficacy of 800 mg orally administered s-adenosylmethionine daily versus placebo for six weeks was investigated in 44 patients with primary fibromyalgia in double-blind settings. Tender point score, isokinetic muscle strength, disease activity, subjective symptoms (visual analog scale), mood parameters and side effects were evaluated. Improvements were seen for clinical disease activity (P = 0.04), pain experienced during the last week (P = 0.002), fatigue (P = 0.02), morning stiffness (P = 0.03) and mood evaluated by Face Scale (P = 0.006) in the actively treated group compared to placebo. The tender point score, isokinetic muscle strength, mood evaluated by Beck Depression Inventory and side effects did not differ in the two treatment groups. S-adenosylmethionine has some beneficial effects on primary fibromyalgia and could be an important option in the treatment hereof.

Administration, Oral

Single cell morphology of muscle in patients with chronic muscle pain.

In 119 patients referred with suspected fibromyalgia, biopsies from the quadriceps muscle were analyzed for "rubber band" morphology, and isokinetic quadriceps strength was measured. Eighty-four fulfilled the criteria for fibromyalgia, 26 had chronic myofascial pain (CMP) and 9 had other diseases including 5 with concomitant fibromyalgia. Twenty-four CMP patients and 48 fibromyalgia patients were randomly selected to match with regard to sex, age, smoking and drinking habits. "Rubber band" morphology was blindly graded on a biopsy score scale from 0 to 2. A statistically significant difference in biopsy score was found between the two matched groups (P = 0.003); median biopsy score in fibromyalgia was 0.42 and 0.25 in CMP. A cut-off value at 0.33 gave a specificity of 71% and a sensitivity of 63%. Isokinetic muscle strength did not differ in the fibromyalgia and CMP groups and was not related to the biopsy score. "Rubber band" morphology is seen more often in fibromyalgia patients than in CMP patients. The exact genesis of this phenomenon is still unknown but theories connected with the possible pathogenesis of the syndrome are presented.

Adult

Isokinetic and isometric muscle strength combined with transcutaneous electrical muscle stimulation in primary fibromyalgia syndrome.

Twenty women with primary fibromyalgia syndrome and 20 age matched healthy women were investigated. The subjects performed maximum voluntary isokinetic contractions of the right quadriceps in an isokinetic dynamometer. Maximum voluntary isometric contractions of the right quadriceps were performed with superimposed transcutaneous electrical stimulation. The examination protocol was repeated after 1 h of resting. Isokinetic and isometric muscle strength was found to be, respectively, 45% (p = 0.0001) and 44% (p = 0.0001) lower in the patient group compared to the healthy subjects. The frequency of superimposed twitches was 65% in the patient group and 15% in the control group (p = 0.003). Patients with primary fibromyalgia have a lower maximum voluntary muscle strength than expected. The increased presence of superimposed electrically elicited twitches during maximum voluntary contraction indicates submaximal force application in primary fibromyalgia syndrome.

Adult

Primary fibromyalgia: clinical parameters in relation to serum procollagen type III aminoterminal peptide.

Serum concentrations of procollagen type III aminoterminal peptide have previously been reported to be low in some patients with primary fibromyalgia and the aim of this study was to determine if such patients differ clinically from primary fibromyalgia patients with normal levels of procollagen type III aminoterminal peptide. Subjective symptoms, tender points and dynamic muscle strength in 45 women with primary fibromyalgia were related to serum concentrations of procollagen type III aminoterminal peptide. Patients with low serum concentrations of procollagen type III aminoterminal peptide had more symptoms, a higher frequency of tender points and lesser quality of sleep compared to patients with normal serum concentrations of procollagen type III aminoterminal peptide (P less than 0.05). They also had a lower dynamic muscle strength (P less than 0.0005). We conclude that the serum concentrations of procollagen type III aminoterminal peptide of primary fibromyalgia patients are connected to the disease impact.

Adult

Screening for autoantibodies in patients with primary fibromyalgia syndrome and a matched control group.

Primary fibromyalgia syndrome (PFS) is a non-articular rheumatic condition characterized by chronic muscular pain. We have performed screening for autoantibodies in 20 women with PFS and in 19 age-matched healthy women. Fifty-five percent of the PFS patients had anti-smooth muscle antibodies and 40% had anti-striated muscle antibodies. None of the control subjects had any muscle antibodies. There was no significant difference in frequency of the remaining autoantibodies between the groups investigated. The present study indicates autoimmune responses in PFS against antigens of the diseased tissue itself, a finding which may be secondary to the disease or have relevance to the still obscure pathogenesis of the syndrome.

Autoantibodies

Patients with polymyositis show changes in muscle protein charges.

Polymyositis (PM) appears with indolent proximal muscle weakness and is an inflammatory disease with breakdown of muscle cells. In our study the protein charge concentrations of the contractile proteins in the A and I bands were determined, applying a microelectrode technique. Patients with PM show a lower protein charge concentration than healthy control subjects which may be caused by the breakdown and removal of the proteins in the contractile filaments. A tool to judge the state of the disease as well as an aid in diagnosis may have been found in this method.

Electrophysiology

Elevated level of beta-adrenoceptors in intact hepatocytes from partially hepatectomized rats.

The binding characteristics of 125I-iodocyanopindolol (125I-ICYP) and 3H-CGP-12177 to intact hepatocytes and a particulate fraction prepared from hepatocytes from sham-operated and partially hepatectomized rats were compared. In the particulate fraction, the beta-adrenoceptor number increased 4-10-fold after partial hepatectomy. 125I-ICYP binding to intact cells demonstrated a high fraction of non-specific binding, although phentolamine was included in the assay to reduce non-specific binding. 3H-CGP-12177 binding to intact cells also demonstrated a higher fraction of non-specific binding than in most cell types. In intact cells, the beta-adrenoceptor number increased 5-6-fold after partial hepatectomy. The number of receptors was comparable in intact cells and the broken cell preparation, indicating that receptors are conserved during the preparation of the particulate fraction.

Adrenergic beta-Antagonists

Down-regulation of surface beta-adrenoceptors on intact human mononuclear leukocytes. Time-course and isoproterenol concentration dependence.

Incubation of human mononuclear leukocytes (MNL) in vitro with isoproterenol resulted in a rapid loss of surface beta-adrenoceptors, determined by radioligand binding at 4 degrees. Isoproterenol concentrations in the range of 10 nM to 100 microM resulted in significant down-regulation of beta-adrenoceptors. At a concentration of 1 microM isoproterenol, the time-dependent loss of surface beta-adrenoceptors closely paralleled the loss in isoproterenol-stimulated adenylate cyclase activity. If receptor number in intact cells was determined at 32 degrees, hardly any loss in receptor number was observed, due to reversal of down-regulation during the incubation period. When beta-adrenoceptor number in broken cell preparations was determined by [125I]cyanopindolol binding at 37 degrees no significant loss was observed, even after 2 hr of isoproterenol treatment, while [3H]CGP-12177 binding resulted in a similar reduction in binding sites as in intact cells. Reversal of loss in surface beta-adrenoceptors was rapid after 1 hr pretreatment with isoproterenol, but followed a biphasic time course after 4 hr pretreatment, with an initial rapid return of about 40% of the down-regulated receptors, followed by a slow, gradual reappearance of receptors. The results indicate that catecholamine exposure leads to a rapid sequestration of MNL surface beta-adrenoceptors away from the cell surface, to a compartment where they are inaccessible to the hydrophilic ligand [3H]CGP-12177 as well as to the lipophilic ligand [125I]cyanopindolol at 4 degrees. Up to 2 hr of isoproterenol treatment does not lead to any breakdown of sequestered beta-adrenoceptors, as they are still recognized by [125I]cyanopindolol binding in broken cell preparations.

Adenylyl Cyclases

Synergism between thapsigargin and the phorbol ester 12-O-tetradecanoylphorbol 13-acetate on the release of [14C]arachidonic acid and histamine from rat peritoneal mast cells.

Thapsigargin is a potent skin irritating sesquiterpene lactone isolated from the roots of Thapsia garganica L. (Apiaceae). In rat peritoneal mast cells thapsigargin induced a calcium-dependent non-cytotoxic [14C]arachidonic acid and histamine release. A minor amount of the released [14C]arachidonic acid was converted to [14C]prostaglandin D2. A potentiated effect was found between thapsigargin and 12-O-tetradecanoylphorbol 13-acetate, as well as between A23187 and the phorbol ester with respect to release of [14C]arachidonic acid and histamine. It is suggested that the synergistic effect is due to activation of protein kinase C by 12-O-tetradecanoylphorbol 13-acetate and to increased intracellular calcium concentration mediated by A23187 as well as thapsigargin. [14C]arachidonic acid was released mainly from phosphatidylcholine. It is suggested that this release may be due to an action of phospholipase A2, and that protein kinase C is involved in activation of phospholipase A2.

Animals

Modes of determining beta-adrenoceptor number in human mononuclear leucocytes.

Inhibition of total 125I-ICYP binding to intact human mononuclear leucocytes at 32 degrees by propranolol and (+/-) CGP-12177 was biphasic. The high affinity component of 125I-ICYP binding, representing approximately 30% of total, was stereospecific, while the low affinity binding site was inhibited without stereospecificity. (-) Isoproterenol inhibited the high affinity component of 125I-ICYP binding only, with low affinity. By performing binding studies in intact cells at 4 degrees or in broken cell preparations at 37 degrees, the fraction of total 125I-ICYP binding representing specific binding was increased, and agonist affinity was high. Inhibition of 3H-CGP-12177 binding to intact cells at 32 degrees demonstrated a high fraction of specific binding and high agonist affinity. Computer-assisted analysis of total radioligand binding determined over a broad concentration range revealed two populations of saturable 125I-ICYP binding sites in intact cells as well as in broken cell preparations, while 3H-CGP-12177 binding demonstrated only one saturable binding site. The number of high affinity 125I-ICYP binding sites was comparable to the number of saturable 3H-CGP-12177 binding sites. Receptor numbers determined by analysis of total radioligand binding were comparable to receptor numbers determined by subtraction of non-specific binding, determined in the presence of a high concentration of competing ligand. Analysis of total radioligand binding was found to be a better procedure because it eliminates the use of an arbitrary concentration of unlabelled ligand and improves the accuracy of the assay.

Adolescent