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Biomedical subjects

B Bengtsson

Publications and source records attributed to B Bengtsson.

At least 127 records · Page 7Linked to original sources
PubMed1981

Methylprednisolone and adrenergic mechanisms in vascular smooth muscle.

The influence of methylprednisolone on noradrenaline-induced contractions and 3H-noradrenaline release was investigated in isolated preparations of rat aorta and portal vein. 20-200 micro M of methylprednisolone had a slight inhibitory effect on the contractions of the aorta but had no effect in the portal vein. The EC50-values noradrenaline were about 10-6 M in both vessels; methylprednisolone did not change it. The steroid changed neither spontaneous nor potassium (127 mM) induced release of 3H-noradrenaline. The potassium (127 mM) induced contracture in the portal vein had 2 phases; the second, at least partly, was produced by released intramural noradrenaline as it was depressed by reserpinization of the animal. Injection of methylprednisolone to the animal 2 h before sacrifice induced a better maintained second phase of the potassium contracture in the portal vein. Although this could mean the release of increased amounts of noradrenaline, other explanations are also possible.

Animals↗
PubMed1981

Manifest glaucoma in the aged I: occurrence nine years after a population survey.

The present study was based on already existing clinical data concerning 599 persons born before 1907, examined during a general ophthalmic survey 1969-72 and still remaining in the same district in July 1980. At the survey 1969-72, 19 out of 1057 persons had manifest glaucoma, 14 were already treated for ocular hypertension, 54 had an IOP greater than 20.5 mmHg and 970 were considered normal. Immediately after the survey, 17 patients were treated for manifest glaucoma and 19 for ocular hypertension. During the following 9 years treated persons were lost to a greater extent (64%) than untreated persons (43%). In July 1980 only 6 persons treated for manifest glaucoma since the survey remained, and 3 of them were socially blind. One out of 7 treated and 2 out of 28 untreated persons with ocular hypertension at the survey had developed visual field defects 9 years later. Manifest glaucomas, often advanced cases, were also detected in 9 persons considered normal at the survey. 5 out of 12 persons with manifest glaucoma detected after the survey had an IOP less than 20.5 mmHg at detection. The visual capacity of persons still remaining in the district 1980 was largely independent of all efforts to prevent blindness from glaucoma in the present population.

Aged↗
PubMed1981

Manifest glaucoma in the aged II: cases detected by ophthalmoscopy.

Ten consecutive cases of manifest glaucoma detected by optic disc assessment in ophthalmic patients born before 1907 were followed. Visual disability and subjective symptoms were common but usually caused by a combination of the glaucoma with other eye diseases. Disc haemorrhages were noted in all cases but two. The highest intraocular pressure recorded was below 23.5 mmHg in all cases but one with disc haemorrhage and one without.

Aged↗
PubMed1981

Disc haemorrhage and glaucoma.

The present material comprises 51 patients with at least one disc haemorrhage in at least one eye. A total of 127 hh were observed. The probability of finding a disc h increases with the number of examinations. The hypothesis that hh occur in all cases of glaucomatous destruction of the papillary tissue cannot be rejected, though not proven. H. seems to be connected with progression of field defects, though its effects are not immediately recognized. H. is detectable very early in the glaucomatous process; the denotation 'forerunner' is most likely justified. Hh. are highly specific for a glaucomatous process, but it has not been possible to connect h. with some clearly delimited group of glaucoma.

Age Factors↗
PubMed1981

The prevalence of glaucoma.

The occurrence of glaucoma was studied in a population comprising 1963 persons born during 1907 to 1921 and living in a small Swedish suburban and rural district. The records of 24 patients treated for glaucoma were examined. An estimate of the prevalence of glaucoma in untreated persons was based on an examination of 1511 subjects by standardised methods (including automatic perimetry) and strict diagnostic criteria. About 20% of all cases of glaucoma with visual field defects in the whole population were already known. Only 7 out of 15 cases of previously unknown but manifest glaucoma had intraocular pressures above 20-5 mmHg. The reduction in visual capacity caused by glaucoma in the present population was limited.

Age Factors↗
PubMed1980

The alteration and asymmetry of cup and disc diameters.

Increases in cupping with time and differences in cup size between the two eyes of one person were studied in a material derived from a general ophthalmic population survey. Cup and disc diameters were measured on fundus photographs. The effect of refraction on the magnification of the eye-camera system was compensated for by the use of a simple correcting factor. The disc diameter increased slowly but steadily with advancing years but the rim area remained unaffected and as a consequence the rim breadth diminished. The increase in disc diameter and the decrease in rim breadth combined to cause marked increase in cup diameter with ageing. A multiple regression analysis showed cup diameters to be independent of refraction as well as of systemic blood pressure and only weakly associated with intraocular pressure. Side differences in cup diameter were strongly dependent on side differences in disc diameter. Some implications of these findings were briefly discussed.

Adult↗
PubMed1980

The inheritance and development of cup and disc diameters.

The familial resemblances in discs diameter (d) and cup diameter residual (e) were studied in 845 individuals forming 297 families and 1040 pairs of spouses and first-degree relatives. The cup diameter residual was computed as the difference between the observed cup diameter and the cup diameter expected from the disc diameter and the age, according to a multiple regression equation. The results for d and e were similar. Spouses did not resemble each other at all. The resemblance between first-degree relatives, on the other hand, was quite substantial. There were no major influences of sex-linkage, dominance or common environment and no obvious maternal effects. It was concluded that the familial resemblance was essentially additively genetic in origin. The heritability was estimated at 2/3. The remaining variance was attributed to errors of development. The results can be applied to other surface dimensions of the optic nerve head.

Adult↗
PubMed1980

Methylprednisolone concentrations in patients with renal transplants as determined by high pressure liquid chromatography.

It is well known that in healthy individuals as well as in patients with diseases receiving glucocorticoids in a given dosage, there is a wide variation in blood concentrations. These may be of importance not only for the efficacy of treatment, but also for the occurrence of side effects. Pharmacokinetic information on glucocorticoids, is scarce mainly because of lack of suitable methods of analysing these drugs in body fluids. A high pressure liquid chromatography (HPLC) method has previously been used for determination of methylprednisolone in plasma (Garg et al., 1977). After modification, this method has been used for determination of methylprednisolone in plasma in healthy subjects and patients with renal transplants. Preliminary data are presented showing a good reproducibility of the method.

Adult↗
PubMed1979

Familial resemblance in casual blood pressure--a maternal effect?

1. The familial resemblance in causal blood pressure was studied in material derived from an ophthalmic population survey. The population consisted of 1078 individuals forming 373 families and 1410 pairs divided into groups with different relationships. In order to adjust for age, the difference between the logarithm of the systolic blood pressure and that of the value expected from a linear regression on age was used instead of the observed pressure. 2. There was no significant correlation between spouses. Children did not resemble their fathers at all. Sons and daughters were significantly correlated with their mothers. The resemblance between siblings was even greater and highly significant. The familial resemblance was not dependent on synchronized pressure readings or on a common household and was not related to the time available for cumulation of effects. 3. Together these findings formed a pattern strongly suggesting long-lasting maternal effects on the systolic blood pressure.

Blood Pressure↗
PubMed1979

Flicker comparison of fundus photographs. A technical note.

A method for comparison of two fundus transparencies by means of alternating flickering light is described. Spurious differences between the pictures are reduced by making the exposures in a fixed position of the pulse cycle. Small haemorrhages are readily detected. Pulse variations of the vessels and changes in size of cup and disc can be measured.

Flicker Fusion↗
PubMed1979

Automatic perimetry in a population survey.

Automatic perimetry was performed in 2998 eyes of 1511 subjects comprising 78% of all persons born 1907--1921 and resident in a certain small area. Unreliable or abnormal tests were repeated. The average number of tests per person was 2.25. About 90% of all tests in normal eyes were performed in less than 3 min. The screening was considered negative in 2887 eyes, incomplete in 20 eyes and positive in 91 eyes (3%). Eighteen of the positives were previously unknown glaucomatous defects. There was only one unexplained "false positive". We concluded that the method is quick, sensitive, specific and dependable. The apparatus is simple to manage and cheap to run.

Aged↗
PubMed1979

Effect of a calcium antagonist on experimental constriction of human brain vessels.

In search for a potent dilatator or deactivator of constriction of cerebrovascular smooth muscle, the effects of a specific antagonist of the calcium influx necessary for the excitation-contraction coupling process was studied on isolated human pial arteries. The arteries were constricted by addition of noradrenaline, 5-hydroxytryptamine, human plasma or blood. All these agents induced a strong contraction which could effectively be reduced by addition of the Ca++-antagonist, nifedipine, to the organ bath. It is suggested that calcium antagonists might be of value in the treatment of cerebrovascular spasm following a subarachnoid hemorrhage.

Calcium↗