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Biomedical subjects

L Svensson

Publications and source records attributed to L Svensson.

At least 217 records · Page 12Linked to original sources
PubMed1985

Enzyme-linked immunosorbent assay for detection of enteric adenovirus 41.

An enzyme-linked immunosorbent assay (ELISA) for direct detection of enteric adenovirus 41 (Ad41) in stool specimens was developed and compared with an Ad40-specific ELISA described previously [Johansson et al, 1980]. Rabbit antiserum to Ad41 was obtained by immunization with purified virions. To eliminate genus-specific reactivity the serum was passed through an immunosorbent column containing soluble adenovirus components of members of subgenera A to E. The anti-Ad41 serum still displayed high reactivity against Ad40 and had to be immunoabsorbed with soluble virus components of Ad40 to be rendered type-specific. The absorbed antiserum was used in an indirect ELISA and proved to be specific for Ad41. No heterotypic reactivity against Ad40 or Ad1 through Ad35 was found. The Ad41-specific ELISA proved to be of equal sensitivity to electron microscopy. The type-specific ELISAs for Ad40 and Ad41 were evaluated by testing 76 stool specimens containing enteric adenoviruses originating from England and Scandinavia. All specimens could be typed--41 (54%) as Ad40 and 35 (46%) as Ad41. These results were confirmed by DNA restriction site analysis. The type-specific ELISA proved to be a specific, sensitive, and a rapid technique for detection of Ad41 and allowed clear-cut discrimination from Ad40 in clinical specimens.

Adenoviruses, Human↗
PubMed1985

Effects of 8-OH-DPAT, lisuride and some ergot-related compounds on the acoustic startle response in the rat.

Five ergot-related compounds were examined for their effects on the acoustic startle response in the rat. The startle amplitude and the startle latency were registered. 8-Hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT; 0.5-8 mg/kg) and lisuride (0.05-0.8 mg/kg) were found to enhance the startle amplitude, while the mainly DA receptor active ergot derivatives pergolide (0.2-0.8 mg/kg), bromocriptine (5-20 mg/kg) and LY 141865 (5-20 mg/kg) had no, or even the reverse, effect. All five compounds caused a prolongation of the startle latency. The increased startle amplitude caused by 8-OH-DPAT (2 mg/kg) and lisuride (0.2 mg/kg) was successfully antagonized by the 5-HT receptor antagonist methiothepin (0.1 mg/kg) but not by metergoline (1 mg/kg). 5-Hydroxy-L-tryptophan (L-5-HTP; 12.5-50 mg/kg), administered to pargyline- and benserazide-pretreated animals, was included for comparison. The serotonin precursor caused a marked increase in the startle amplitude and a shortening of the startle latency.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1985

Influence of dietary partially hydrogenated vegetable and marine oils on membrane composition and function of liver microsomes and platelets in the rat.

The aim of the present study was to investigate the influence of partially hydrogenated vegetable and marine oils on membrane composition and function of liver microsomes and platelets with particular reference to the metabolism of linoleic acid and the production of arachidonic acid metabolites. Four groups of male weanling rats were fed linoleic acid supplemented diets containing 20% (w/w) of partially hydrogenated low erucic acid rapeseed oil (HLRSO), partially hydrogenated herring oil (HHO), olive oil (OO) and trierucin + triolein (TE) for 10 weeks. An additional two groups were fed partially hydrogenated low erucic acid rapeseed oil and partially hydrogenated herring oil without linoleic acid supplementation (HLRSO- and HHO-, respectively). Substantial amounts of trans fatty acids were incorporated into liver microsomes (12.6% in group HLRSO) and platelets (7.0% in group HLRSO-). This incorporation was not dependent on the dietary linoleic acid level. Hepatic microsomal delta5 -desaturase activity was significantly increased after HLRSO feeding compared to 00 feeding. Delta6 -Desaturase activity did not vary in the linoleic acid supplemented groups. Both delta5 -and delta6 -desaturase activities were significantly increased in groups without linoleic acid supplementation. Docosenoic acid was incorporated into platelet phospholipids in contrast to liver microsomes. In the platelet, docosenoic acid seemed to have a special preference for phosphatidylserine. Very small amounts were incorporated into platelet phosphatidylinositol. Feeding diets HLRSO, HHO and 00 did not influence rat platelet cyclooxygenase or 12-lipoxygenase activity. Platelets from rats fed TE, however, produced significantly less 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) than platelets from rats fed OO. Feeding of HLRSO- and HHO- resulted in a significantly diminished production of the arachidonic acid metabolites 12-HETE, 12-hydroxy-5,8,10-heptadecatrienoic acid (HHT) and 6-keto-prostaglandin F1alpha in stimulated platelets and aorta. Thus, high dietary levels of trans isomers of monoenoic acids do not interfere with platelet cyclooxygenase or lipoxygenase activity provided sufficient amounts of linoleic acid are available.

Animals↗
PubMed1985

Behavioral reactivity in spontaneously hypertensive rats.

Spontaneously hypertensive rats of the Okamoto strain (SHR) were compared with inbred normotensive rats of the Wistar-Kyoto strain (WKY) and with normally bred Wistar rats (NT) in tests on the audiogenic immobility reaction (freezing), open-field behavior in a dark and an enlightened arena respectively, auditory startle response and male sexual behavior. Compared to the WKYs the SHRs showed increased locomotion and rearing in the open-field situations, reduced startle response and shortened immobility reaction. The SHRs differed in the same way from the NT rats with the exception for motor activity in the dark arena, where no differences were observed. The WKY rats showed less motor activity than the NT animals. Both SH and WKY rats showed shorter latency time for ejaculation than the NT rats. The characteristics of the behavior patterns displayed by the SH rats were interpreted as indicating a reduced propensity for fear reactions in this strain of rats compared to the WKY and NT strains used in the present study.

Acoustic Stimulation↗
PubMed1985

Treatment of recurrent genital herpes simplex infections with oral acyclovir.

A total of 113 patients with recurrent genital herpes were enrolled in a multicentre cross-over study. Two consecutive recurrences were treated with either oral acyclovir 200 mg or matching placebo five times daily for five days. Acyclovir significantly reduced the time to crusting and healing and the duration of new lesions and symptoms. Acyclovir was not found to have any clinically significant effect on the haematological or biochemical parameters measured, or to have caused adverse events and was well tolerated. Early self-initiated treatment may abort a recurrent attack of genital herpes without progression to the ulcerative or crusting stage.

Acyclovir↗
PubMed1985

Functional residual capacity, thoracoabdominal dimensions, and central blood volume during general anesthesia with muscle paralysis and mechanical ventilation.

Functional residual capacity (FRC), rib cage and abdominal dimensions (rc-ab), central blood volume (CBV), and extra vascular lung water (EVLW) were measured in six lung-healthy subjects awake and during halothane anesthesia, muscle paralysis, and mechanical ventilation. FRC was assessed by multiple breath nitrogen washout, rc-ab dimensions by computerized tomography, and CBV and EVLW by a double-indicator dilution technique (thermo-dye). During anesthesia, FRC decreased by 0.5 1 (17%). The cross-sectional chest area was reduced by 12-20 cm2, causing an approximate reduction in thoracic volume by 0.3 1. Concomitantly, the diaphragm was moved cranially by an average of 1.9 cm, diminishing the thoracic volume a further 0.5 1. The abdominal cross-sectional area did not alter significantly, despite the shift of the diaphragm. CBV decreased by 0.3 1. EVLW did not change significantly. It is concluded that the thoracic volume is reduced during halothane anesthesia, muscle paralysis, and mechanical ventilation as a result of cranial shift of the diaphragm and reduction in transverse area. The decrease in thoracic volume is accompanied by a reduction in FRC and a displacement of blood from the thorax to the abdomen, the transverse area of the latter thus being maintained despite the shift of the diaphragm.

Abdomen↗
PubMed1985

Pulmonary densities during anesthesia with muscular relaxation--a proposal of atelectasis.

Twenty patients (23-76 yr) were studied with regard to lung tissue changes prior to and following induction of general anesthesia with muscular relaxation, and another four subjects were studied for a longer period awake. The transverse thoracic area and the structure of the lung tissue were determined by computerized tomography. No abnormalities in the lung tissue were noted before anesthesia. Within 5 min after induction, including muscular relaxation, all subjects had developed crest-shaped changes of increased density in the dependent regions of both lungs. They were largest in the most caudal segment (4.8 +/- 0.8% of the transverse lung area, mean +/- SE) and smaller in the cephalad exposures (3.4 +/- 0.7% of the transverse area). The size of the densities showed no correlation to age. The densities did not increase after a further 20 min of anesthesia and were not affected by the inspiratory oxygen fraction. When the subjects were moved from the supine to the lateral position, the crest-shaped densities disappeared in the nondependent lung and remained in the dorsal part of the dependent lung. The application of positive end-expiratory pressure of 10 cmH2O eliminated or reduced the densities. The four awake subjects showed no lung densities after 90 min in the supine position. It is suggested that these crest-shaped densities represent atelectases, which develop by compression of lung tissue rather than by resorption of gas.

Adult↗
PubMed1985

Antiarrhythmic effect of reducing myocardial noradrenaline stores with alpha-methyl-meta-tyrosine.

In the adrenergic neurons the amino acid alpha-methyl-meta-tyrosine (alpha-MmT) is converted to metaraminol via the noradrenaline (NA) synthetic pathway. Metaraminol thereby displaces NA from its neuronal stores, and as a consequence NA levels can be drastically reduced, although normal sympathetic tone is essentially maintained by release of newly synthetized NA. In rats treated with alpha-MmT methylester (400 + 200 mg/kg) myocardial NA was reduced to less than 10% of control. Under barbiturate anesthesia, the left coronary artery was ligated, and the incidence of ventricular fibrillation and mortality during a 30-min period was recorded. Before ligation, mean arterial blood pressure was unchanged and heart rate slightly increased by alpha-MmT pretreatment. The energy state of the myocardium was also unchanged by the alpha-MmT pretreatment, as seen in a separate study where hearts from identically treated rats were taken for analysis of glycogen and adenine nucleotides. Thus, alpha-MmT pretreatment appeared not to have reduced the sympathetic tone of the heart. In spite of this, alpha-MmT pretreatment reduced the ventricular fibrillation from 65 to 33% (p less than 0.01; chi 2 test) and mortality from 37 to 15% (p less than 0.05). The results indicate an important role of myocardial NA stores in the development of early ischemic arrhythmias.

Animals↗
PubMed1985

Use of dodecyl sulfate as an esterase inhibitor before gas-chromatographic determination of labile beta-adrenoceptor blocking drugs.

Sodium dodecyl sulfate (SDS) was introduced as an esterase inhibitor in the determination of two extremely labile, ultrashort-acting beta-blockers-esmolol and flumolol--in whole blood. SDS was much more efficient than previously used agents in preventing hydrolysis. The assay comprises solvent extraction, perfluoroacylation, and capillary gas-chromatography with electron-capture detection. The limit of detection (the concentration at which the coefficient of variation is 10-15%) for the drugs is 5 nmol/L of whole blood.

Adrenergic beta-Antagonists↗
PubMed1985

Laparoscopic findings and contraceptive use in women with signs and symptoms suggestive of acute salpingitis.

Laparoscopic findings in women with clinical signs and symptoms of pelvic inflammatory disease were correlated with contraceptive use in a case-control study. Of the 738 women, 544 (73.7%) had laparoscopic signs of acute salpingitis, whereas 194 (26.3%) had visually normal fallopian tubes (nonsalpingitis). Acute salpingitis was seen in 59.8% of the 286 patients using oral contraceptives, in 80.6% of the 227 patients using an intrauterine device (IUD), and in 84.4% of the 225 patients using barrier methods or not using contraceptives (reference group). To estimate the relative risk of acute salpingitis, logistic regression analysis adjusting for age and duration of pain before laparoscopy was used. For oral contraceptive users versus the reference group the adjusted relative risk was estimated at 0.24 (95% confidence interval 0.15 to 0.38, P less than .0001), and for IUD users versus the reference group a relative risk was estimated at 0.83 (95% confidence interval 0.49 to 1.38, P = .46). The relative risk of salpingitis among oral contraceptive users versus the reference group was 0.22 (P = .005), and 0.06 (P = .001) for women infected with Chlamydia trachomatis and/or Neisseria gonorrhoeae, respectively. In patients with pelvic inflammatory disease, spread of the inflammation to the fallopian tubes seems to be inhibited in oral contraceptive users.

Adolescent↗
PubMed1985

Fluorescein flowmetry: a method for measuring relative capillary blood flow in the intestine.

The present work represents an attempt to develop a method for measuring relative blood flow in intestinal capillaries, by the use of sodium fluorescein (Na-F) as an indicator substance. The method is called fluorescein flowmetry (FF). A mathematical model was developed; blood flow was expressed as an index between the maximum fluorescence obtained during the first circulatory passage of Na-F and the rise time, defined as the time interval between 10 and 90% of the maximum fluorescence. The prerequisites for the mathematical model were tested in experiments in animals and man. The extraction of Na-F in the intestinal capillaries was found to be more than 99%. The ratio between the tissue clearance and uptake was found to be 0.0051, indicating no back flux. Experiments in man revealed that the rise time was proportional to the mean transit time and the mean transversal time of the bolus proper. The accuracy of FF was confirmed in man where the ratio between mucosal and serosal-muscular capillary blood flow was 2:1. From the results obtained, it appears that FF can be used as a method for measuring relative capillary blood flow in the intestine.

Animals↗
PubMed1985

Ectopic pregnancy and antibodies to Chlamydia trachomatis.

Ectopic pregnancy is one of the most serious sequelae to acute salpingitis. Chlamydia trachomatis seems to be the most common etiologic agent of acute salpingitis. In the present study, we tested whether women with ectopic pregnancy had serologic evidence of a current or past chlamydial infection. Sixty-five percent of the women with ectopic pregnancy had IgG serum antibodies to C. trachomatis, and 21% of women pregnant in utero had such antibodies. Eleven percent of women with infertile husbands, 42% of women with cervicitis, and 69% of women with salpingitis had IgG serum antibodies to C. trachomatis. In women with ectopic pregnancy, there was a correlation between the occurrence of IgG antibodies and a history of salpingitis or gross evidence of a previous tubal inflammation. We conclude that previous chlamydial salpingitis may be a major etiologic factor leading to ectopic pregnancy.

Adult↗
PubMed1984

Antagonism by haloperidol of the suppression of exploratory locomotor activity induced by the local application of (-)3-(3-hydroxyphenyl)-N-n-propylpiperidine into the nucleus accumbens of the rat.

The injection of (-)3-PPP into the nucleus accumbens, 10 microgram/side, produced a suppression of exploratory locomotor activity without affecting treadmill locomotion. Furthermore, the suppression of exploratory locomotor activity produced by (-)3-PPP was antagonized by the administration of haloperidol, 25-50 micrograms/kg i.p.

Animals↗
PubMed1984

Spinal monoaminergic modulation of masculine copulatory behavior in the rat.

The sexual behavior of male rats receiving infusions of 5-HT, dopamine and noradrenaline intrathecally in the spinal cord of intracerebroventricularly (i.c.v.) in the lateral ventricle was observed. Intrathecal infusions of 5-HT and noradrenaline inhibited penile insertions and ejaculation, noradrenaline being the more potent of the amines. Dopamine was without effect. I.c.v. amine infusions impaired to various extents the masculine mating pattern, primarily by interfering with the males' tendency to approach the females. The facilitation of mating seen after intrathecal administration of the aminotetraline, 8-OH-DPAT, was more pronounced than that observed following its i.c.v. infusion.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1984

Contraceptives and acute salpingitis.

In 546 women with a first episode of salpingitis, the degree of inflammation of the fallopian tubes, as seen during laparoscopy, was graded into mild, moderate, and severe. The patients were subgrouped according to contraceptive use into (1) reference group (women not using intrauterine [contraceptive] devices [IUDs] or oral contraceptives [OCs]) (2) IUD group, and (3) OC group. Mild, moderate, and severe salpingitis occurred in 51.3%, 34.6%, and 24.1% of the women in the reference group. The corresponding percentages for the women in the IUD group were 54.6%, 29.7%, and 15.7%, and for the patients in the OC group, 73.5%, 17.1%, and 9.4%, respectively. Women using OCs had significantly milder degrees of inflammation of the fallopian tubes than women with other contraceptive methods. Age could not explain the differences.

Acute Disease↗
PubMed1984

Identification of an outer capsid glycoprotein of human rotavirus by concanavalin A.

An outer capsid glycoprotein of human rotavirus (serotype 1) was localized and characterized by use of lectins, electron microscopy and a modified Western blotting technique. Lectins with specificity for fucose, galactose, glucose and mannose were mixed with purified single- or double-shelled human rotavirus. Aggregates observed by electron microscopy were obtained with double-shelled virus and concanavalin A, the only tested lectin with mannose specificity. By SDS-polyacrylamide gel electrophoretic analysis nine structural polypeptides could be identified. Five of these polypeptides were components of the inner capsid (VP1, VP2, VP3, VP4, VP6) and four components of the outer capsid (VP5, VP7, VP8, VP9). When using a modified Western blotting technique employed for glycoprotein detection, only VP7 was found to be glycosylated. This glycoprotein could be identified in rotavirus from human stools as well as from cell cultures. Heterogeneity in molecular weight of VP7 was observed in different isolates. An unexpected heterogeneity of VP7 was seen within a human rotavirus strain. An unplaqued stock of virus was found to exhibit two distinguishable glycoprotein bands (VP7, VP7a). After 10 passages in MA-104 cells the same strain was found to exhibit only one glycoprotein band.

Capsid↗
PubMed1984

Importance of enteric adenoviruses 40 and 41 in acute gastroenteritis in infants and young children.

In a prospective 1-year study of acute infantile gastroenteritis, adenoviruses were detected in the stools or by seroconversions, or both, in 56 of 416 (13.5%) ill children. By use of DNA restriction enzyme analysis, enzyme immunoassay, and culture techniques, 33 of 56 (59%) adenovirus specimens were identified as enteric adenoviruses 40 and 41 (Ad40 and Ad41). They were found as the sole recognizable cause of diarrhea in 30 of 416 (7.2%) ill children and in 0 of 200 controls. Three additional ill children had enteric adenoviruses as a part of a dual infection. Evidence for established adenoviruses (Ad1 through Ad39) in gastroenteritis was found in 15 of 416 (3.6%) ill children but also in 3 of 200 (1.5%) controls. Eight adenovirus specimens remained untyped. Seroconversions were demonstrated in 17 of 18 (94%) paired serum samples from patients shedding enteric adenoviruses. The predominant symptom of infections with enteric adenoviruses was diarrhea, with a mean duration of 8.6 days (Ad40) and 12.2 days (Ad41). One-third of the children with Ad41 infections had prolonged symptoms (greater than or equal to 14 days). The frequency of respiratory symptoms was low (21%). The established adenoviruses presented a different clinical picture, characterized by diarrhea of shorter duration, higher fever, and significantly increased occurrence of respiratory symptoms (79%). In conclusion, enteric adenoviruses appear to be an important cause of acute infantile gastroenteritis, second only to rotaviruses in this study.

Acute Disease↗