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K Persson

Publications and source records attributed to K Persson.

At least 163 records · Page 9Linked to original sources
PubMed1993

Nitric oxide synthase in pig lower urinary tract: immunohistochemistry, NADPH diaphorase histochemistry and functional effects.

1. The distribution and colocalization of nitric oxide synthase (NOS)-like immunoreactivity and NADPH diaphorase activity in the pig lower urinary tract were investigated by immunohistochemical and histochemical staining techniques. Functional in vitro studies were performed to correlate the presence of NOS-immunoreactivity/NADPH diaphorase staining with smooth muscle responses involving the L-arginine/nitric oxide (NO) pathway. 2. NOS-immunoreactivity and NADPH diaphorase activity were expressed in nerve trunks and fine nerve fibres in and/or around muscular bundles in the detrusor, trigone and urethra. Thin nerve fibres that dispersed within the muscle bundles were mainly found in the urethral/trigonal area, whereas such fibres were less common in the detrusor. 3. Almost all neuronal structures that were NOS-immunolabeled were also stained for NADPH diaphorase. In contrast, the urothelium, which was intensively stained by the NADPH diaphorase technique, remained unstained by immunohistochemistry. 4. Electrical field stimulation of pig isolated trigonal and urethral preparations induced relaxations, which were inhibited by tetrodotoxin (1 microM) and NG-nitro-L-arginine (L-NOARG, 10 microM). 5. L-Arginine (1 mM), but not D-arginine, inhibited (25-30%) electrically evoked detrusor contractions. This inhibition was reversed by L-NOARG (0.1 mM). L-Arginine did not inhibit detrusor contractions in the presence of scopolamine (1 microM) and had no direct smooth muscle effects per se. 6. Acetylcholine (1 nM-10 microM) caused concentration-dependent relaxations of noradrenaline-induced contractions in pig vesical arteries. Removal of the endothelium practically abolished the acetylcholine-induced relaxation. Pretreatment with L-NOARG (0.1 mM and 0.3 mM) caused a rightward shift of the concentration-response curves to acetylcholine, but the maximal relaxation obtained was significantly reduced (to 65 +/- 12%; n = 6; P < 0.05) only at 0.3 mM L-NOARG. 7. In vessel segments contracted with K+ (60 mM), acetylcholine induced concentration-dependent relaxations. When the vessels were incubated with 0.3 mM L-NOARG and then contracted with K+ (60 mM) all relaxant responses to acetylcholine were abolished. 8. The presence of NO synthesizing enzyme in nerve fibres and the pharmacological evidence for NO-mediated relaxation of the trigone and urethra suggest that NO or a NO-related substance may have a role in inhibitory neurotransmission in these regions. In the detrusor, the presence of NO-synthesizing enzyme in nerves can be demonstrated, but its functional importance is unclear. NO, as well as other endothelium-derived factors seem to be involved in the endothelium-dependent acetylcholine-induced relaxation of pig vesical arteries.

Acetylcholine↗
PubMed1993

The L-arginine/nitric oxide pathway in the rabbit urethral lamina propria.

A non-adrenergic, non-cholinergic (NANC)-mediated relaxation has been demonstrated in the female rabbit urethral lamina propria, both in response to electrical stimulation and after administration of acetylcholine. The present study was performed to investigate if these relaxations are mediated via the L-arginine/nitric oxide (NO) pathway. In the lamina propria of the female rabbit urethra, numerous NADPH diaphorase-positive, fine varicose nerve fibres were observed both around arteries, in and around smooth muscle bundles, and in arterial endothelium. Since NADPH diaphorase histochemistry may be a marker of NO synthase-containing neurons, this finding suggests the occurrence of NO synthase in this tissue. Isolated preparations of the rabbit urethral lamina propria, contracted by noradrenaline, produced frequency-dependent NANC relaxations in response to electrical field stimulation, and concentration-dependent NANC relaxations in response to acetylcholine. Electrically induced relaxations were possible to evoke even in preparations where acetylcholine-induced relaxation was poor or absent. Pretreatment with the NO synthase inhibitor, NG-nitro-L-arginine (L-NOARG) reduced the maximum relaxation obtained at 30 Hz to 12% of the control response. NG-nitro-D-arginine (D-NOARG) had no effect. The effects of L-NOARG were antagonized by the addition of L-arginine. Acetylcholine relaxed noradrenaline-precontracted strips by 36%; vasoactive intestinal polypeptide (VIP) reduced the contraction by 95%. L-NOARG, but not D-NOARG, abolished or reversed acetylcholine-induced relaxations, but failed to reduce the relaxations produced by VIP. The results demonstrate the occurrence of NADPH diaphorase-positive nerve fibres in the lamina propria of the female rabbit urethra.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗
PubMed1993

Evaluation of molecular typing for epidemiological study of Chlamydia trachomatis genital infections.

Molecular typing and serotyping were compared for 150 Chlamydia trachomatis strains isolated from genital sources, belonging to 10 different serovars. Because of the general agreement of the two methods, molecular omp1 genotyping was applied to the epidemiological study of C. trachomatis isolates from genital infections in Bordeaux (France), during a 29-month period. The most prevalent omp1 genotypes were E (51.7%), F (17.3%), D (8.8%), and G (8.4%). Restriction enzyme analysis allowed identification of a serovar D variant (Dv), whereas serovar E strains were homogeneous.

Bacterial Outer Membrane Proteins↗
PubMed1993

A protocol for structured observation of motor performance in preterm and term infants.

A new protocol for structured observation of motor performance has been designed for assessment of the progress and quality of motor development in preterm and term infants. A detailed scale of motor development based on the present knowledge of motor development in healthy term infants has been constructed. The motor performance is observed in each part of the infant's body in the supine and prone positions and in the whole body with the infant sitting, standing and during locomotion, and is evaluated in relation to defined levels of motor performance. If the quality of motor performance is optimal for a certain level, no deviation is noted. Any deviation from the motor performance described in the protocol for the level in question is graded as suspected or clear and classified by type. All observations are recorded on videotape for documentation. In a study of inter- and intraobserver agreement, such recordings from 17 infants were reassessed on two occasions more than one year apart. The interobserver agreement ranged between 73 and 87% and the intraobserver consistency between 77 and 88%. The protocol is currently being used in a follow-up study.

Clinical Protocols↗
PubMed1993

A protocol for structured observation of motor performance in preterm and term infants. Interobserver agreement and intraobserver consistency.

A new protocol for structured observation of motor performance, for use both in term and preterm infants, has been tested regarding interobserver agreement and intraobserver consistency. Ten different motor items are assessed concerning the developmental level as described in the protocol. Any deviations from the description of the level are noted. The two main observers twice reassessed video recordings of 17 infants who had primarily been assessed by them both in an ongoing follow-up study. The two observers arrived at the same level of development in 75% of the observed items at the first reassessment and in 81% at the second, and agreed concerning deviation in 73 and 79% of the observations at the two reassessments, respectively. Each observer arrived at the same level of development at all three assessments in 62% of the observed items. Thus when used by these two observers the protocol has an acceptable degree of interobserver agreement and intraobserver consistency.

Clinical Protocols↗
PubMed1992

[TWAR infection is a common diagnosis in outpatient clinics].

Infections caused by Chlamydia pneumoniae were first described in 1985. The infection can cause common cold, sore throat, hoarseness, cough, headache, fatigue and sometimes influenza-like illness. Examination can indicate serous otitis media, sinusitis, laryngitis, bronchitis and pneumonia. The course can be long and relapsing. The recommended drugs for treatment are tetracycline or erythromycin for at least two weeks. Five verified cases are described in the article, four of them with symptoms from the upper respiratory tract only. It is concluded that Chlamydia pneumoniae is a not unusual cause of upper airway diseases. Up to now the diagnosis can best be verified by micro immunofluorescence. The authors call for a rapid and reliable test for use in physician's office. It is proposed that infections caused by Chlamydia pneumoniae be termed TWAR.

Adolescent↗
PubMed1992

The postoperative pharmacokinetics of codeine.

The metabolism and systemic availability of codeine have been studied in 12 patients after cholecystectomy. They were given 20 mg codeine as an IV bolus dose on the first day after surgery and 50 mg codeine as a single oral on the fourth day after surgery. Codeine had a medium to high extraction ratio and a total plasma clearance of 10.8 (4.3) ml.min-1.kg-1. The clearance varied four-fold between subjects. All the patients were extensive metabolizers with regard to the debrisoquine/sparteine polymorphism, as tested using dextromethorphan as the probe drug. Nevertheless, the formation of morphine from codeine was very small and plasma morphine concentrations were below the detection limit of 3.3 nmol.l-1 (1 ng.ml-1). As a corollary, the morphine/codeine ratio in the the concentration-time curves was less than 3% in all the patients. The systemic availability of codeine varied extensively between subjects (range 12-84%). This might partly explain differences in the dose of codeine required as an analgesic.

Adult↗
PubMed1992

Patellar tendon rupture. Description of a simplified operative method for a current therapeutic problem.

A simple operative method for the treatment of patellar tendon rupture is introduced. The operative procedure is described and we present the short-term results of the first seven patellar tendon ruptures that have been treated accordingly at our clinic. The technique is easily reproducible and utilizes a minimum of foreign body implant. A secondary procedure for removal of suture material is rarely necessary.

Adult↗
PubMed1992

Bovine neutrophils recruited by endotoxin to a teat cistern continuously produce oxygen radicals and show increased phagocytosis and extracellular chemiluminescence.

Bovine neutrophils were harvested from a teat cistern following endotoxin infusion and were compared with blood neutrophils by measurements of chemiluminescent and phagocytic activity towards C3- and IgG-opsonized and unopsonized yeast particles. Both phagocytosis and luminol-dependent chemiluminescence elicited by all three particles were enhanced in the teat cells. The increase in the luminol-dependent chemiluminescence towards C3- and IgG-opsonized particles was due to an enhanced extracellular release of myeloperoxidase. The observed increase in phagocytosis of unopsonized yeast was shown to reflect the interaction between up-regulated CR3 receptors on the surface of the teat neutrophils and the yeast particles. A high chemiluminescent activity of the teat neutrophils in both the luminol- and lucigenin-dependent systems in the absence of a phagocytic prey indicated that the NADPH oxidase was permanently active and that myeloperoxidase was continuously released by the cells. Treatment of neutrophils with cytochalasin B showed that the chemiluminescence and phagocytosis of teat neutrophils were less sensitive to this drug than that of blood neutrophils. These results indicate that the teat neutrophils have up-regulated their receptors for IgG- and C3-opsonized and unopsonized yeast on the cell surface by the action of actin. The cells also have a permanently active NADPH oxidase dependent on the association with actin and show a higher tendency than blood neutrophils to secrete the content of their primary granules during phagocytosis.

Actins↗
PubMed1992

Endothelin-1-induced contractions of isolated pig detrusor and vesical arterial smooth muscle: calcium dependence and phosphoinositide hydrolysis.

1. In isolated pig detrusor and vesical arterial smooth muscle preparations, endothelin-1 (ET-1) caused concentration-dependent contractions. Nifedipine (10(-6) M) did not significantly affect the action of ET-1 in the vessels, but almost abolished its effect in the detrusor. Incubation for 30 min in Ca(2+)-free solution markedly reduced the ET-1-induced contractions in both detrusor and vesical arteries. 2. The protein kinase C inhibitor H-7 (3 x 10(-5) M), reduced the response to ET-1 in detrusor muscle as well as in vessels, and abolished the contractions evoked by ET-1 in Ca(2+)-free solution. 3. ET-1 caused an increase in the accumulation of inositol phosphates (IPs) in preparations prelabelled with myo-[3H]inositol. After exposure to ET-1 (10(-7) M) for 60 min, an approx. 4-fold increase in IPs levels were demonstrated, compared to untreated controls, in both detrusor and vessel preparations. Pretreatment with nifedipine (10(-6) M) did not reduce IPs formation. In contrast, no increase in IPs formation was demonstrated in Ca(2+)-free medium. 4. The increase in accumulation of IPs was slow in onset in both detrusor and vesical arteries, with no significant accumulation demonstrable during the first 30 min. Time-course studies of tension development for ET-1 revealed that maximum tension was reached before significant levels of IPs could be detected.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1992

Chlamydial antibodies and deoxyribonucleic acid in patients with ectopic pregnancy.

OBJECTIVE: To evaluate the importance of previous and persisting chlamydial infection for ectopic pregnancy (EP). DESIGN: A prospective study of women with EP. SETTING: Hospitalized patients. PATIENTS AND CONTROLS: Eighty-six women with EP with (group I; n = 35) or without (group II; n = 51) risk factors for EP and chlamydial infection. Age-matched normally pregnant women served as controls. INTERVENTIONS: Blood samples were drawn from patients and controls for antibody determination. MAIN OUTCOME MEASURES: The frequency of immunoglobulin G antibodies was compared between patients and controls, and the polymerase chain reaction (PCR) was used to detect chlamydial deoxyribonucleic acid (DNA) in tubal tissue from 33 patients (70 specimens). RESULTS: Immunoglobulin G antibodies (titer greater than or equal to 32) were significantly more common among patients than in controls (51% versus 31%, P less than 0.025). The difference was more pronounced between group I and controls (69% versus 31%, P less than 0.005). Chlamydial DNA was not detected in any tubal specimen. CONCLUSIONS: An association was found between previous chlamydial infection (serologically) and EP, especially in women with risk factors, but no evidence of persisting chlamydial infection in the tubes could be demonstrated using PCR.

Adult↗
PubMed1992

Electrically-induced, nerve-mediated relaxation of rabbit urethra involves nitric oxide.

Isolated smooth muscle preparations from the rabbit urethra precontracted with noradrenaline (10(-5) M), endothelin (10(-7) M), or arginine vasopressin (10(-7) M) responded to electrical field stimulation by frequency-dependent non-adrenergic, non-cholinergic relaxations, which could be blocked by tetrodotoxin (10(-6) M). Relaxation was more pronounced in preparations precontracted by endothelin than by noradrenaline or arginine vasopressin. The electrically induced relaxations were reduced in a concentration-dependent manner by pretreatment for 30 minutes with NG-nitro-L-arginine (10(-6) to 10(-4) M) and NG-monomethyl-L-arginine (10(-5) to 10(-4) M). At the highest concentration of NG-nitro-L-arginine used (10(-4) M), relaxation was abolished and/or changed into a contraction. The effect of NG-nitro-L-arginine was reversible. NG-nitro-D-arginine had no effect. Pretreatment for 30 minutes with L-arginine (10(-3) M) slightly, but significantly, enhanced the maximum relaxation to field stimulation in noradrenaline-precontracted preparations. L-arginine pretreatment also prevented the effects of low, but not high, concentrations of NG-nitro-L-arginine. In contrast, D-arginine had no effect. Electrically induced relaxations were not significantly affected by methylene blue (10(-5) M) or superoxide dismutase (20 U/ml). Addition of nitric oxide (present in acidified solution of NaNO2) caused transient and concentration-dependent relaxations in preparations precontracted by noradrenaline. At the maximum concentration used (10(-3) M), the relaxant response averaged 67% of the tension induced by noradrenaline. Nitric-oxide-induced relaxations were not affected by NG-nitro-L-arginine or L-arginine, but were significantly inhibited by methylene blue. In preliminary experiments, effects similar to those found in rabbit urethra were also observed in isolated urethral preparations obtained from three patients. It is suggested that in the urethra, nitric oxide is involved in the mediation of relaxation evoked by electrical stimulation of nerves.

Animals↗
PubMed1992

Phospholipase C activation by endothelin-1 and noradrenaline in isolated penile erectile tissue from rabbit.

The effects of endothelin-1 and noradrenaline on phospholipase C activity in the rabbit isolated corpus cavernosum were investigated by measuring the accumulation of inositol phosphates. Both endothelin-1 and noradrenaline caused a time- and concentration-dependent increase in the accumulation of 3H-inositol phosphates in preparations prelabelled with 3H-myo-inositol. The reaction was slow in onset with no significant accumulation of 3H-inositol phosphates, including inositol trisphosphate, demonstrable during the first 15 minutes. At 60 minutes, the mean increases in 3H-inositol inositol phosphates induced by 3 x 10(-7) M endothelin-1 and 10(-3) M noradrenaline amounted to 341 and 530% of time-matched controls, respectively. However, when given at concentrations having the same contractile amplitude on rabbit corpus cavernosum, there was no difference in the amounts of 3H-inositol phosphates generated by endothelin-1 and noradrenaline. Prazosin (10(-6) M) significantly inhibited the stimulatory effect of noradrenaline on phosphoinositide hydrolysis. Pretreatment with 10(-6) M nimodipine did not reduce the increases in 3H-inositol phosphates induced by 3 x 10(-7) M endothelin-1 and 10(-3)M noradrenaline. Also in Ca(2+)-free medium, both agonists had significant stimulatory effects on phosphoinositide turnover, although under this condition, the responses were greatly reduced. The results suggest that exogenous endothelin-1 and noradrenaline activate phospholipase C in corpus cavernosum, and that this mechanism is partly independent of extracellular Ca2+. Considering the slow onset of action, phospholipase C activation is probably not directly involved in rapid contractile events, but may be of importance in the long-term regulation of penile smooth muscle tone.

Animals↗
PubMed1992

Immunoglobulins, lysozyme and lactoferrin in the teat and udder of the dry cow during endotoxin-induced inflammation.

Immunoglobulins (Ig) and antibacterial proteins like lysozyme and lactoferrin are components of the humoral defence against infections. Changes in Ig, lysozyme and lactoferrin concentrations during endotoxin-induced inflammation in the test cistern and udder quarter of the dry cow were studied. Surgical closure of the passage between teat and udder cisterns enabled studies of reactions in the teat cistern without interference of the mammary gland. After endotoxin infusion, IgG1, IgG2, lysozyme, and to some extent IgM, increased in the teats and udder quarters, and were positively correlated with changes in somatic cell counts. No significant changes were observed in IgA or lactoferrin. The origin and significance of Ig, lysozyme and lactoferrin in the bovine teat and udder are discussed. Ig probably originated both from serum and from local plasma cells, while leukocytes appeared to be the source of lysozyme during inflammation. Secretory epithelium appeared to be the source of lactoferrin. Support for this theory was the almost total absence of lactoferrin in teat cistern samples.

Animals↗
PubMed1992

Nitric oxide and relaxation of pig lower urinary tract.

1. We studied the non-adrenergic, non-cholinergic (NANC) nerve-mediated relaxation induced by electrical stimulation in pig isolated lower urinary tract smooth muscle, and the possible involvement of the L-arginine (L-ARG)/nitric oxide (NO) pathway in this response. 2. Trigonal strips, precontracted by noradrenaline (NA), carbachol or endothelin-1 (ET-1), relaxed frequency-dependently in response to electrical stimulation. Maximum relaxation was obtained at 6-8 Hz, and amounted to 56 +/- 2%, 77 +/- 3% and 62 +/- 6% of the agonist-induced tension in preparations contracted by NA, carbachol, or ET-1, respectively. Exposure to NG-nitro-L-arginine (L-NOARG; 10(-7)-10(-5) M) concentration-dependently reduced the relaxant response in preparations contracted by NA. L-NOARG (10(-6) M) reduced the maximal response to 51 +/- 8% of control. L-NOARG (10(-5) M) abolished all relaxation, and unmasked a contractile component; D-NOARG had no effect. Also in trigonal preparations, where the tension had been raised by carbachol or ET-1, L-NOARG (10(-5) M) markedly reduced relaxations evoked by electrical stimulation. 3. In trigonal preparations contracted by NA, maximal relaxation was increased after pretreatment with L-ARG (10(-3) M), and the inhibitory effect of L-NOARG (10(-6) M) was prevented. Incubation of the trigonal strips with methylene blue had no effect on relaxations elicited at frequencies less than 6 Hz, but a small inhibition was observed at higher frequencies. 4. Administration of NO (present in acidified solution of NaNO2) induced concentration-dependent relaxations in trigonal preparations contracted by NA, carbachol, or ET-1.L-NOARG (10-5 M) and L-ARG (10-3M) had no effect on these relaxations. However, methylene blue (10-S M) significantly shifted the concentration-response curve for NO to the right. NANC-relaxation and NO-induced relaxation of trigonal preparations were both inhibited by oxyhaemoglobin (10-5 M) and pyrogallol (10-4 M).5. In urethral preparations precontracted by NA, electrical stimulation caused frequency-dependent relaxations. A maximum relaxation of 73 +/- 4% was obtained at 10 Hz. Also in the urethra, NANCrelaxation was blocked by L-NOARG (10-5 M), and a contractile response generally appeared.6. Detrusor strips treated with alpha-beta methylene ATP (10-i M) and atropine (10-6 M), and then contracted by ET-1, showed relaxations (19 +/- 3% of the induced tension) in response to electrical field stimulation (2-20 Hz) only when the tension was high. No response at all, or small contractions, were found in response to electrical stimulation in K+ (35 mM)-contracted detrusor strips. Detrusor preparations contracted by carbachol were concentration-dependently relaxed by exogenously administered NO, SIN-1 (NO-donor), and isoprenaline, whereas vasoactive intestinal polypeptide had minor effects. NO and SIN-1 induced maximal relaxations of 63 +/- 3% and 70 +/- 4%, respectively, of the tension induced by carbachol. Isoprenaline produced an almost complete relaxation (96 +/- 4%).7. The results suggest that NANC-nerve mediated relaxation, involving the L-ARG/NO pathway, can be demonstrated consistently in the pig trigonal and urethral, but not in detrusor smooth muscle. The importance of this pathway for lower urinary tract physiology and pathophysiology remains to be established.

Animals↗