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Biomedical subjects

B Winblad

Publications and source records attributed to B Winblad.

At least 487 records · Page 27Linked to original sources
PubMed1982

Brain monoamine abnormalities in the two types of Creutzfeldt-Jakob disease.

Analysis of monoamine concentrations in brain tissue was carried out on the two types of Creutzfeldt-Jakob disease (CJD). The results showed decreased levels of catecholamines compared to control cases in a number of areas, and the reductions were most pronounced for dopamine. In general, the case classified as the amyotrophic form of CJD showed a greater degree of a monoamine loss than the case with spongiform encephalopathy, which is the typical transmissible form of CJD. These findings support the scarce available data indicating disturbances in the catecholaminergic systems in these types of brain diseases, and may have therapeutic implications.

Aged↗
PubMed1981

Distribution of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in human brain in relation to age, drug influence, agonal status and circadian variation.

The post-mortem brain concentrations of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were determined in 16 parts of the brain from patients with no history of neurologic, psychiatric or metabolic illness. The causes of death were either ischemic heart disease, infections disease, cancer or accidents. Forty-two men with a mean age of 57 years (range 18-95 years) and 19 women with a mean age of 62 years (range 23-79 years) were included. The influence of several factors were studied: brain weight, time between death and autopsy, storage time before chemical analysis, age, sex, agonal status, cerebral arteriosclerosis, cancer, opiate treatment and time of death during the day. Most correlations between the 5-HT concentrations in different brain parts were positive, the strongest correlations in the basal ganglia and the limbic system. No consistent pattern of age-related 5-HT changes were found. The females had significantly higher 5-HIAA concentrations in the cortex of the gyrus hippocampus. Final hypoxia seemed to decrease 5-HT concentrations. Opiate treatment reduced 5-HT and increased 5-HIAA concentrations. A marked circadian variation of 5-HT was found, most pronounced in the hypothalamus, the limbic system and some neocortical areas.

Adolescent↗
PubMed1981

Monoamine oxidase-A and -B activities in the brain stem of schizophrenics and non-schizophrenic psychotics.

In the pons of autopsy cases who had suffered from chronic schizophrenic or nonschizophrenic psychoses, an increased activity of monoamine oxidase -B but not -A was found, as compared with age-matched controls. Consequently, the ratio of the activities of MAO-B : MAO-A was elevated in the cases of psychosis. There was no significant difference in enzyme activities between schizophrenic and nonschizophrenic psychoses. Lobotomy appeared not to influence the monoamine oxidase activity. Increased ratios of the activities of MAO-B : MAO-A in various brain parts of chronic schizophrenics in comparison with age-matched controls was found in the previously published data of Eckert et al (1980) and Schwartz et al. (1974) but not Crow et al. (1979). The mechanism underlying the change in enzyme activities is unclear. There seems to exist an association between an increased monoamine oxidase-B activity and degenerative processes in the brain resulting in loss of neuronal activity. The change observed may be linked either to pathological processes associated with chronic psychosis or to long-term treatment with neuroleptic drugs.

Adult↗
PubMed1981

Platelet monoamine oxidase activity in Down's syndrome.

The activity of platelet monoamine oxidase in Down's syndrome cases was significantly lower than that of controls. This difference was found for both males and females, and with tyramine, tryptamine and beta-phenethylamine as substrate. The Km values of the monoamine oxidase towards tryptamine as substrate from controls and Down's syndrome patients were similar.

Adolescent↗
PubMed1981

Prevalence of dementia disorders in institutionalized Swedish old people. The work load imposed by caring for these patients.

The prevalence of dementia disorders were determined among 3,523 institutionalized patients aged 65 years or more in the county of Västerbotten. Approximately one-third of the clientele were considered demented. The prevalence was calculated to be 3.7% of the population in the county. The frequency of dementia disorders among the patients in the somatic long-stay wards, the nursing homes, and the mental hospital was rather similar (55-65%). A surprisingly high percentage of demented (17.1%) was found in the homes for the aged. The work load was highest in the somatic long-stay wards and in the nursing homes. Patients in the mental hospital, however, differed markedly from those in other institutions with higher scores for aggressive and disturbing behaviour, which accounted for the large number of patients in the mental hospital with maximal work load. The findings are discussed with regard to future institutional care of demented patients and point out the need for better education in psychiatric care for the staff.

Activities of Daily Living↗
PubMed1981

Ampicillin treatment of Neisseria gonorrhoeae in vivo. An experimental study in rabbits.

The effect of ampicillin on gonococci was investigated in chambers subcutaneously implanted in rabbits. An intramuscular injection of ampicillin resulted in a rapid increase of the ampicillin concentration in serum, whereas the diffusion of ampicillin into the fluid of a non-infected chamber was comparatively slow. The ampicillin concentration was, however, maintained in the chamber fluid during a prolonged period of time as compared to ampicillin in serum. The concentration profile of ampicillin in the infected chamber was similar to that of the non-infected chamber, though at a lower level. No viable gonococci were detected 120 minutes after the injection of ampicillin. In contrast, the same concentration of ampicillin in a liquid culture resulted in slower reduction in the viability of the gonococcal strain. Even after 300 minutes a small population of gonococci was viable. Thus, a difference in the activity of ampicillin could be observed between the in vitro and the in vivo test situation.

Ampicillin↗
PubMed1981

51cr-release assay for quantitation of membrane bound and solubilized Thy-1 antigen.

A method for quantitative determination of mouse Thy-1 antigen is presented. Antigen to be assayed is incubated with anti-Thy-1 serum and remaining antibody activity is measured by adding 51Cr-labelled thymocytes and complement. The detection limit corresponds to the amount of Thy-1 antigen exposed on the surface of 25,000 thymocytes, which can be calculated to correspond to approximately 0.5 ng. The assay was designed to be performed in the presence or absence of detergent, and is therefore a useful tool for quantitation of Thy-1 in purification procedures and studies on the biological significance of this membrane antigen.

Animals↗
PubMed1981

Manifestation and growth of a transplantable osteosarcoma in mice: the effects of thymectomy and thymosin treatment.

Normal and thymectomized CBA mice treated with and without thymosin were injected with 2 x 10(6) viable osteosarcoma cells. The activity and weight of tumors, the cell-mediated and humoral-immune responses against the tumors, and the light microscopic characteristics suggested that thymectomy resulted in a significantly decreased tumor frequency. There were also significant increases in cell-mediated cytotoxic activity in vitro as measured by lysis of 51Cr-labeled tumor cells incubated with spleen cells, and in lymphocytic infiltration around the tumors. While thymosin treatment of thymectomized mice restored these parameters to those of intact animals, thymosin had no demonstrable effects on nonthymectomized animals.

Animals↗
PubMed1980

Titration of human brain monoamine oxidase -A and -B by clorgyline and L-deprenil.

The interaction of clorgyline and L-deprenil with the -A and -B forms of human brain monoamine oxidase (MAO) has been studied. Both compounds inhibit cerebrocortical MAO in a manner consistent with a 'suicide' inactivation of the enzyme. The interaction of clorgyline with the -A form of the enzyme appears to take place almost entirely at specific binding sites, and the conditions required for this inhibitor to 'titrate' the concentrations of MAO-A have been elucidated. L-Deprenil has also been used to titrate the concentration of the -B form of MAO in cerebrocortical homogenates, but there is a considerable degree of non-specific binding of this compound. The two inhibitors have been used to titrate the concentrations of the two enzyme forms in frontal cortex homogenates from different age groups. There was a significantly higher MAO-B activity for the age range 73--95 years than for the age range 2--63 years. No significant differences between the two age groups were found for MAO-A. The activity of MAO-A in the samples correlated very well with the concentration of this enzyme form. Titration of the B-form of the enzyme with L-deprenil indicated an increased enzyme concentration with age, although other factors, such as the non-specific binding of this compound, could contribute to this effect.

Adult↗
PubMed1980

Titration of human brain type-B monoamine oxidase.

The interaction of the substrate-selective irreversible inhibitor J-508 [N-methyl-N-propargyl-(1-indanyl)-ammonium hydrochloride] with the B form of human brain monoamine oxidase has been investigated, and the conditions necessary for this inhibitor to "titrate" the concentration of this enzyme form determined. It was found that the concentration of monoamine oxidase-B determined in this way was the same when either benzylamine or beta-phenethylamine was used to assay for activity, which would indicate that this enzyme form is not heterogeneous. Furthermore, the variation in activity from sample to sample was found to be due to a variation in the concentration of available monoamine oxidase-B active centers, raher than due to a variation in the molecular turnover numbers of this enzyme form towards its amine substrates.

Alkynes↗