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Biomedical subjects

B Larsson

Publications and source records attributed to B Larsson.

At least 271 records · Page 15Linked to original sources

Gilbert's syndrome--does it exist? A study of the prevalence of symptoms in Gilbert's syndrome.

Liver function tests and prevalence of different symptoms generally said to occur in Gilbert's syndrome were analysed in male conscripts and in male and female participants in two cross-sectional population studies in Göteborg, in total 2395 subjects. The serum bilirubin levels showed a skew distribution without bimodality. We observed no tendency to higher prevalence of symptoms in subjects with high serum bilirubin levels, but normal alkaline phosphatase and aminotransferase values compared to subjects with normal bilirubin. The findings contradict the existence of a disease entity named "Gilbert's syndrome".

Adolescent↗

A cellular analysis of immunosuppression in cattle with mucosal disease.

Eleven cattle with mucosal disease (MD) were investigated to determine the constitution and function of the cells participating in the immune response. The total numbers of blood mononuclear cells varied within the normal range but a poor response of the lymphocytes to mitogen stimulation indicated a state of immunosuppression in the cattle with MD. Identification of subpopulations of the mononuclear cells revealed that eight of the cattle with MD had an increased proportion of B cells. However, the proportions of monocytes and T cells were in the normal ranges, resulting in a low proportion of cells not identified as being either B or T cells (null cells). Three of the cattle with MD had an increased proportion of cells with receptor for the Fc part of IgG (Fc gamma + cells). Bovine Fc gamma + cells have previously been shown to exert suppressor activity, as was also demonstrated in the present study by increased mitogen induced lymphocyte stimulation following removal of the Fc gamma + cells. The effect of depletion of Fc gamma + cells was at least five-fold greater in the two cattle with MD tested than the two controls. It appears that a diminished number of null cells and, or, increased suppressor cell activity might contribute to the observed immunosuppression in cattle affected with MD.

Animals↗

Quantitative neutron capture radiography for studying the biodistribution of tumor-seeking boron-containing compounds.

Biodistribution of two compounds presently considered for use in neutron capture therapy has been studied in mice carrying a transplantable Harding-Passey melanoma. A method is described by which quantitative assessment can be made of the boron distribution in whole-body sections of such animals. An alpha-particle-sensitive film is placed in close contact with a freeze-dried section of an animal and exposed to neutrons. The tracks visible after etching are analyzed optoelectronically in fields of 0.6 X 0.6 mm2 and compared to standards of boron homogeneously distributed in liver homogenates. The dynamic range of this method is about two orders of magnitude in concentration, with a lower detection limit of 0.1 to 0.01 ppm 10B, depending on the rate of induction of spurious tracks by fast neutrons present in the neutron beam chosen. In a transplantable Harding-Passey melanoma in mice, it was found that the sulfhydryl boron hydride Na2B12H11SH presently used for therapy of glioblastoma clears blood, muscle, and brain very rapidly. Its accumulation in tumors was persistent for more than three days. A higher tumor accumulation was observed with its disulfide, which has been suggested for neutron capture therapy. For both compounds, a marked heterogeneity of boron distribution within one tumor was found.

Animals↗

Analysis of risk factors for stroke in a cohort of men born in 1913.

We analyzed parental death from stroke and other potential risk factors in relation to the incidence of stroke among 789 men, all 54 years old at the base-line examination. During 18.5 years of follow-up, 57 men (7.2 percent) had strokes. In univariate analyses, the following characteristics correlated significantly with the incidence of stroke: increased systolic (P = 0.004) and diastolic blood pressure (P = 0.0001), larger waist circumference (P = 0.007), higher waist:hip ratio (P = 0.0004), increased plasma fibrinogen level (P = 0.01), and lower vital capacity (P = 0.03). In addition, men whose mothers had died of stroke had a threefold increase in their incidence of stroke as compared with men without such a maternal history (P = 0.0005). Potential risk factors for stroke that were not confirmed were body-mass index, serum cholesterol level, hematocrit, blood glucose level, smoking, coronary heart disease, electrocardiographic signs of left ventricular hypertrophy, and a paternal history of death from stroke. In multivariate analyses, increased blood pressure, abdominal obesity, increased plasma fibrinogen level, and maternal history still correlated significantly with the risk of stroke. A maternal history of stroke should probably be added to the list of risk factors for stroke among middle-aged men.

Abdomen↗

Diabetes mellitus in Swedish middle-aged men. The study of men born in 1913 and 1923.

As part of a study of the epidemiology of diabetes mellitus in middle-aged Swedish men, the present paper reports the prevalence and incidence of diabetes and the prevalence of impaired glucose tolerance. Two cohorts of 50-year-old men, representative of the corresponding male population of Gothenburg, Sweden, were examined in 1963 and 1973, respectively, and then followed until 1980. In the cohort of men born in 1913 (n = 855) the diabetes prevalence (WHO criteria), based on a questionnaire and fasting blood glucose, increased from 1.5% at age 50 to 7.6% at age 67. In the cohort of men born in 1923 (n = 226) the prevalence was 3.7% at age 50 and 4.0% at age 57. The overall prevalence of diabetes and impaired glucose tolerance was 25% among men born in 1913 (age 67) and 18% among men born in 1923 (age 57). The cumulative risk of developing diabetes from age 50 to 67 was 7.8%. Variables associated with impaired glucose tolerance and newly found diabetes, when degree of obesity was considered, were systolic blood pressure and triglycerides, well known risk factors for both coronary heart disease and diabetes. Uric acid, fasting insulin and glutamic puruvic transaminase, recently discussed as possible risk factors, were also associated with impaired glucose tolerance and newly found diabetes. Thus, both impaired glucose tolerance and newly found diabetes were associated with a clustering of risk factors, not only for diabetes but also for coronary heart disease.

Blood Glucose↗

Does a gradually decreasing menstrual blood loss (MBL) in women wearing a Cu-IUD indicate a risk for an accidental pregnancy?

In three separate series, comprising 71 women using either a Gravigard, a Nova-T or a Multiload contraceptive device, the menstrual blood loss (MBL) was quantitatively assessed before and after insertion of each respective IUD. In three women, an involuntary pregnancy was registered with the IUD in situ. In these three women a successively diminishing MBL was registered during the last 3 months before conception, while none of the remaining women included in the series experienced any accidental pregnancy or any reduction of the MBL. Thus, this report emphasizes the potential risk for an accidental pregnancy in women wearing a Cu-IUD if successively diminishing MBLs are observed.

Adult↗

The effect of oral contraceptive pills on levels of oxytocin in plasma and on cognitive functions.

Millions of healthy women use combined oral contraceptives (o.c.) for decades. In spite of that, little is known about their possible effects on cognitive functions. In this open cross-over study, 20 women were examined twice at four-week intervals at a fixed period of the menstrual cycle when they were and when they were not taking o.c. They were examined with a test-battery to assess cognitive functions. Blood samples were taken before and after breakfast to assess levels of oxytocin and prolactin. A significant increase in levels of oxytocin was registered when the women were on o.c. There was no significant difference in performance on the psychometric tests when the participants were on o.c. compared to when they were without o.c.

Adult↗

Does an intracervical infection influence the fibrinolytic activity and the collagen content of the fetal membranes? A study of ascending infections in pregnant ewes.

Apart from solely mechanical explanations, premature rupture of the membranes (PROM) has been suggested to be caused by an ascending infection. In order to investigate the role of infection in the mechanism of PROM, pregnant ewes were experimentally inoculated endocervically with either Bacteroides fragilis, Streptococcus intermedius or group B streptococci. These microorganisms were previously reported to be implicated in PROM in humans. The present investigation concerns the possible effect of an experimentally induced ascending infection on the collagen content and fibrinolytic activity (FA) of the fetal membranes. No relationship was observed between an ascending infection during pregnancy and the collagen content content of the fetal membrane specimens. It was concluded that changes in the collagen content bear no etiological significance in the mechanism of premature membrane rupture irrespective of an ascending infection's being present or not. Concerning FA in only one case, experiencing a Strept. intermedius amnionitis, was an elevated FA value observed. This finding indicates that the involvement of FA in the process of membrane rupture following ascending infection during pregnancy cannot be ruled out.

Animals↗

Ketanserin interaction with urethral alpha-adrenoceptors.

The selective 5-HT2 receptor blocker ketanserin was found to reduce maximal urethral pressures in healthy females by about 40% without reducing blood pressure. In vitro, ketanserin completely or almost completely reduced contractions of the isolated female rabbit urethra induced by phenylephrine, noradrenaline (NA) and electrical field stimulation. The drug was less effective against responses evoked by clonidine and 5-hydroxytryptamine (5-HT). 5-HT-induced contractions were effectively reduced by methysergide, but little affected by prazosin and rauwolscine. In concentrations exceeding 10(-7) M ketanserin significantly increased efflux of 3H in 3H-NA preloaded preparations of rabbit urethral muscle. Low concentrations of 5-HT, less than 10(-6) M, had slight inhibitory effects of 3H release, whereas 5-HT 10(-5) M caused a significant increase. It is concluded that ketanserin counteracts the effects of postjunctional alpha 1-adrenoceptor stimulation in isolated rabbit urethra. Such an effect might also explain its urethral pressure lowering action in man.

Adult↗

Cardiac and pulmonary causes of dyspnoea--validation of a scoring test for clinical-epidemiological use: the Study of Men Born in 1913.

Dyspnoea is one of the earliest symptoms in several conditions, such as heart disease and airway obstruction. However, the early phases of these two conditions are hard to distinguish in a reproducible way. In a population study of the natural history and epidemiology of congestive heart failure a scoring test to differentiate the two conditions was developed. In this report the test is presented and evaluated against various clinical and laboratory measures in 644 men sampled from the general population. The test provides a 'cardiac score' and a 'pulmonary score', both based on history and findings at the physical examination. Men who had pulmonary scores (indicating a pulmonary cause of the dyspnoea) had significantly lower values of spirometry variables but no significant pulmonary congestion at X-ray compared to a reference group (no dyspnoea, no pulmonary scores). Men with cardiac scores had significantly larger hearts and more congestion but no significant change of variables measuring airways obstruction compared to the reference group (no dyspnoea, no cardiac scores). Even though there was a moderate overlap of impaired cardiac and pulmonary function in the dyspnoea group, perhaps due to smoking being a common causal agent, the test appears to differentiate the causes of dyspnoea in a manner similar to clinical evaluation but, in contrast to the latter, in a defined and therefore reproducible way.

Aged↗

Dyspnoea in a cross-sectional and a longitudinal study of middle-aged men: the Study of Men Born in 1913 and 1923.

In a longitudinal population study, 855 men, born in 1913 and initially examined when 50 years old, were followed for 17 years with measurements of dyspnoea and other variables performed at ages 50, 54, and 67 years. In addition a sample of 226 men born in 1923 was followed from 50 to 57 years of age. At the latest examination, four different methods for measuring dyspnoea were used, one based on questionnaire, one on interview, and two on visual analogue scales. The estimates from these methods were highly intercorrelated, and correlated with measures of cardiopulmonary function as well. The prevalence of dyspnoea grade 2 (shortness of breath when walking with someone of the same age on the level) or more, not counting the mildest form of dyspnoea in these populations, was 2.8%, 3.0%, 5.2% and 10.3% at 50, 54, 57 and 67 years of age, respectively. Dyspnoea grade 1 (shortness of breath when walking quickly on the level or uphill) was less well related to age. A scoring system to differentiate various possible causes of dyspnoea was applied. About one third of the dyspnoeic men had signs and symptoms of cardiac disease, one quarter had pulmonary disease, and a quarter had a combination of both causes. The remaining 20% had no signs or symptoms indicating cardiopulmonary disease but in the majority of the cases other plausible causes were found.

Aged↗

Therapist-assisted versus self-help relaxation treatment of chronic headaches in adolescents: a school-based intervention.

This study compared the relative efficacy of a therapist-assisted relaxation treatment programme with a self-help approach and a self-monitoring condition in the treatment of chronic headaches in adolescents within a school setting. The subjects were 46 high school students, 16-18 years of age, who were randomly assigned to the three treatment conditions. The results indicated that the self-help approach was as effective as the therapist-assisted relaxation condition in reducing the students' headache, and that these findings were maintained at a 5-month follow-up evaluation. The results suggest that the self-help relaxation procedure is a potential low-cost alternative treatment to a more traditional therapist-based intervention condition.

Adolescent↗

Theoretical and functional studies on alpha 1-and alpha 2-adrenoreceptors: an examination using the Schild plot.

1 The influence on the shape of the Schild plot by a two-receptor system was studied in both functional and theoretical studies. In the functional studies, the alpha-adrenoreceptors in cat lingual arteries were studied since both alpha 1- and alpha 2-adrenoreceptors have been suggested to contribute to the noradrenaline-induced contractile response in this tissue. 2 The Schild plots constructed using noradrenaline (NA) as agonist and prazosin as antagonist gave a straight line with a slope close to unity. In contrast, the corresponding Schild plot constructed for rauwolscine appeared to be biphasic. 3 The results obtained in the functional study were discussed in view of Schild plots obtained from a theoretical model which was designed to take into consideration the presence of two distinct types of receptor, the percentile proportions of which could be altered. 4 The theoretical model indicates that the shape of the Schild plot can vary considerably depending on the relative contribution of each receptor subtype to the contractile response, the selectivity of the antagonist, and the range and number of antagonist concentrations used. 5 It is suggested that a response is predominantly mediated by alpha 1-adrenoreceptors and less by alpha 2-adrenoreceptors when the Schild plot for prazosin gives a slope close to unity and has a pA2-value representative for alpha 1-adrenoreceptors, and rauwolscine gives a slope less than unity and a significant shift of the NA concentration-response curve in concentrations around 10(-8) M. When the reverse is true (but with a significant shift caused by prazosin already at a concentration around 10(-9) M) the contraction elicited by NA is proposed to be predominantly mediated by alpha 2-adrenoreceptors and less by alpha 1-adrenoreceptors.

Animals↗

Is the collagen content reduced when the fetal membranes rupture? A clinical study of term and prematurely ruptured membranes.

In 15 patients experiencing premature rupture of the fetal membranes (PROM) and in 15 control subjects having delivered spontaneously at term, the collagen content of the membranes was determined by the hydroxyproline method. From each patient two membrane specimens were obtained, one from the rupture margin and another from the membranes in close relation to the placental margin. No significant difference in the collagen content was demonstrated between the two groups of patients. Moreover, no significant difference was observed comparing the collagen content within the paired membrane specimens of each patient in each group. Neither was there any obvious change in the membrane collagen content in relation to clinical signs of chorioamnionitis or microbiological findings. It is concluded that changes in the collagen content of the fetal membranes bear no significance as to the etiology of PROM, neither is such a change involved in the mechanism of membrane rupture at term.

Adolescent↗

Body mass index in the Scandinavian countries.

Data on the body mass index (BMI) from four Scandinavian countries are compared. The Finnish values are markedly higher than those of the other countries. This holds for both sexes. Among these the Norwegians deviate by showing higher values for females, though not reaching the Finnish level, but lower values for the males. The populations from which the observations are drawn are differently sampled. There is no evidence that differences as to composition in rural/urban populations can explain the differences.

Adult↗