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Biomedical subjects

K Berglund

Publications and source records attributed to K Berglund.

At least 19 recordsLinked to original sources
PubMed1998

Potentiation of transmitter release by protein kinase C in goldfish retinal bipolar cells.

1. We examined whether transmitter release could be modified by the activation of protein kinase C (PKC) of retinal bipolar cells. A bipolar cell with a large axon terminal was isolated from the goldfish retina. The presynaptic Ca2+ current was measured under whole-cell voltage clamp, and the released transmitter (probably glutamate) was detected electrophysiologically by using the response of NMDA receptors of catfish horizontal cells as a reporter. 2. Transmitter release was potentiated by a PKC activator, phorbol 12-myristate 13-acetate (PMA), but not by an ineffective phorbol ester, 4alpha-phorbol 12,13-didecanoate. A PKC inhibitor, bisindolylmaleimide I, did not affect the transmitter release by itself but blocked the PMA-induced potentiation of transmitter release. These results suggest that the actions of PMA were mediated via the activation of PKC. 3. Introduction of 5 mM EGTA into the presynaptic terminals of bipolar cells revealed two separate components of transmitter release. A rapid component was triggered immediately after depolarization while a slow component appeared with a delay. Application of PMA selectively potentiated the slow component without affecting the Ca2+ dependence of exocytosis. 4. We suggest that the activation of PKC may modify the recruitment process of synaptic vesicles in retinal bipolar cells.

Animals↗
PubMed1998

Submillisecond kinetics of glutamate release from a sensory synapse.

Exocytosis-mediated glutamate release from ribbon-type synaptic terminals of retinal bipolar cells was studied using AMPA receptors and simultaneous membrane capacitance measurements. Release onset (delay <0.8 ms) and offset were closely tied to Ca2+ channel opening and closing. Asynchronous release was not copious and we estimate that there are approximately 5 Ca2+ channels per docked synaptic vesicle. Depending on Ca2+ current amplitude, release occurred in a single fast bout or in two successive bouts with fast and slow onset kinetics. The second, slower bout may reflect a mobilization rate of reserve vesicles toward fusion sites that is accelerated by increasing Ca2+ influx. Bipolar cell synaptic ribbons thus are remarkably versatile signal transducers, capable of transmitting rapidly changing sensory input, as well as sustained stimuli, due to their large pool of releasable vesicles.

Animals↗
PubMed1997

Bone mineral density in normal Swedish women.

We examined 429 women, aged 20-80 years, randomly selected from the population register to establish normal values for bone mineral density (BMD) in Swedish women. BMD of the spine and hip was measured by dual-energy X-ray absorptiometry (DEXA; Hologic QDR 1000) and in the forearm by single photon absorptiometry (SPA; Molsgaard ND-1100). The recalled age of menarche was negatively correlated to BMD at all ages. There was no significant change in BMD from 20-49 years at any site except a slight decline at Ward's triangle. Bone loss was rapid at all sites during the first decade after menopause. Thereafter, BMD declined slowly in the trochanter and total hip but more rapidly in the forearm, femoral neck, and Ward's triangle. BMD in the spine even increased in the eighth decade probably due to osteoarthritis. The average change in forearm BMD during the 15 perimenopausal years comprising mean age for menopause +/- 2 SD (43-57 years) was -0.4% per year in premenopausal females and -1.6% per year in postmenopausal females. The corresponding annual percental change was, for the spine, +0.2 and -1.7; neck, -0.7 and -1.7; trochanter, +0.5 and -1.5; and Ward's triangle, -0.1% and -2.2%, respectively. Our normal values for lumbar spine BMD prior to menopause did not differ from published values or the manufacturer's normal values; however, our spine BMD values for the first decade after menopause were significantly lower (approximately 10%) than in other studies. Our femoral neck BMD values for younger women were, like those of several other groups, significantly lower than the manufacturer's normal values, but our sample of young women in this study was small. The prevalence of osteoporosis, if defined as t score < -2.5 is highly dependent on the sampling of the reference population of young adult women, and also on the choice of skeletal site. Further studies on bone mineral density in healthy young adult women are needed.

Absorptiometry, Photon↗
PubMed1996

A structure of self-conceptions and illness conceptions in rheumatoid arthritis (RA).

In 2 independent samples of RA patients, a large pool of self-reported illness experiences were statistically examined for content and structure of common types of self-conceptions and illness conceptions related to living with rheumatoid arthritis (RA). Multivariate analyses revealed 7 primary factors in both samples. Three constituted a positive continuum (fighting spirit, acceptance, revaluation), and 3 a negative (deprivation of life values, protest, reserved). The 7th factor (denial) was weaker and conceptually intermediate. The obtained factors contained many items similar to those in other established psychological instruments used in research on RA, but showed stronger relations to subjective well-being (mood) than any one of these. Disease indicators correlated only weakly with RA self-conceptions (RASC) and mood. The RASC factors appear to more broadly reflect different facets of positive and negative ways of individual experience of living with RA than other published instruments. They were tentatively interpreted as RA-specific expressions of dispositions towards positive and negative affect, respectively.

Activities of Daily Living↗
PubMed1996

Hyperparathyroidism and long-term lithium therapy--a cross-sectional study and the effect of lithium withdrawal.

OBJECTIVES: To assess in patients with long-term lithium treatment the incidence and prevalence of hypercalcaemia and hyperparathyroidism, and to evaluate the relationship between parathyroid function and renal function: also, to examine the effect of treatment discontinuation. DESIGN: Part 1. An epidemiological cross-sectional study covering defined catchment areas. Part 2. A lithium withdrawal study in a subgroup of the patients who were examined after a mean of 8.5 (4-16) weeks off lithium. Comparisons were made with a group of psychiatric non-lithium patients matched for sex and age. SETTING: Outpatient treatment at nine psychiatric departments in southern Sweden. SUBJECTS: Inclusion criterion was 15 years or more on lithium. Excluded from Part 2 were patients with a high risk of relapse. Out of 215 identified patients. 142 (66%) entered and completed Part 1, while 13 of the latter entered and completed Part 2. RESULTS: The point prevalence of persistent hypercalcaemia was 3.6% and of surgically verified hyperparathyroidism 2.7%. The observed incidence of hyperparathyroidism over 19 years was 6.3%. It was significantly higher than expected in females. In the withdrawal group serum calcium was significantly increased compared to controls, and did not change during 8.5 weeks without lithium. Isostenuria was significantly more common among patients with than without hyperparathyroidism. CONCLUSIONS: The point prevalence, and the 19-year incidence of hyperparathyroidism, were increased. The point prevalence of hypercalcaemia was also increased, and not reversible during 8.5 weeks off lithium. The findings support the hypothesis of a causal relationship between lithium treatment and hyperparathyroidism. Hypercalcaemia and hyperparathyroidism are sometimes aetiologically related to reduced renal function in long-term lithium patients.

Adult↗
PubMed1995

Hip fractures in Nordic cities: difference in incidence.

All new hip fractures referred to hospital in 1989 were recorded in seven urban populations from Denmark, Finland, Norway and Sweden. The total population at risk (50 years and older) was 588,427, and 4075 fractures were observed (76.5% women). In all cities an age-dependent increase in incidence was found, and the female incidence was highest. When comparing the incidence rates after direct standardization, significant differences in hip fracture incidence were found between the cities for both women and men. The standardized relative rates seemed to decrease when moving south and east with the lowest rates found in Tampere, Finland. This indicates that factors which differ even between urban populations within a restricted geographical region may have an important impact on hip fracture incidence.

Aging↗
PubMed1993

Inter-observer variation in assessment of the prostate by digital rectal examination.

In a prospective study, inter-observer variation in the assessment of the prostate by digital rectal examination (DRE) by a urologist and a general practitioner was analysed. The 2 physicians performed independent assessment of the prostate in 933 men aged 50 to 69 years with regard to 9 variables as part of a screening programme for carcinoma of the prostate. Complete agreement for all observations was reached in 46.5% of the men. Using kappa (K) statistics, the values were adjusted for the expected chance agreement. K values between 0.485 and 0.682 were obtained for 6 variables representing good agreement; these were size, tenderness, midline furrow, symmetry, induration and nodularity. Agreement regarding fixation, lateral sulci and seminal vesicles was poor owing to the small number of cases deviating from normal. Contrary to the general belief that DRE is highly subjective, our results show a good correspondence between the observations of the examiners when assessing the prostate in a systematic way.

Aged↗
PubMed1993

Results, principles and pitfalls in the management of renal AA-amyloidosis; a 10-21 year followup of 16 patients with rheumatic disease treated with alkylating cytostatics.

OBJECTIVE: To assess renal functional outcome at 10-21 years in 16 consecutive patients with rheumatic disease, treated with alkylating agents for secondary renal AA-amyloidosis, and to review management principles developed during 21 years. METHODS: Renal function was assessed by S-creatinine and the albumin/creatinine clearance ratio, and arthritic activity by joint score and C-reactive protein (CRP). In the event of signs of renal deterioration, cyclophosphamide, or since 1975 chlorambucil, was given until stable remission of the arthritis was obtained. RESULTS: Of the 7 cases of precipitous uremia that occurred, 4 were not treated with cytostatics at the patients' local hospitals. By 1992, median survival of renal function was 11 years (range 4-21). At 10 years 12 (75%) still had kidneys with preserved function, and at that stage accounted for 22 instances of renal deterioration treated with alkylating agents for periods of 6-45 months (median 13). Renal function was improved in 18 of these instances, and deterioration arrested in 3, the general trend being stabilized or moderately increased S-creatinine and successively declining proteinuria. Prompt institution of corticosteroid treatment is regarded as indispensable at increase of CRP/S-AA due to infection or surgery. CONCLUSION: Our results indicate that the survival of renal function may be substantially prolonged (compared to no treatment) when cyclophosphamide, or preferably chlorambucil, is appropriately administered at signs of kidney deterioration due to active arthritis, and lifelong, continuous monitoring maintained.

Albumins↗
PubMed1992

Maternal smoking and irradiation during pregnancy as risk factors for child leukemia.

The effect of joint exposure to diagnostic X-rays and maternal smoking during pregnancy was compared in a case-control study of 216 children with cancer (128 cases with acute lymphoblastic leukemia [ALL] and 88 with solid tumors) and 301 control children with insulin-dependent diabetes mellitus (IDDM). Exposure to diagnostic X-rays combined with smoking of ten or more cigarettes per day gave a relative risk of 3.6 (95% CI, 1.8 to 7.0) and a positive dose response relation for ALL in the offspring (p less than 0.001). When examined alone, X-rays gave a relative risk of 1.8 (95% CI, 1.1 to 3.1), and smoking a relative risk of 2.2 (95% CI, 1.1 to 4.5). No similar trend was seen for solid tumors. Potential confounding was examined after stratification on maternal smoking-diagnostic X-ray exposure and each of potential confounders, but there was little change in the risk ratio. We conclude that the risk of ALL in the offspring was more than threefold higher when smoking was combined with diagnostic X-ray during pregnancy.

Adolescent↗
PubMed1991

Increased hip-fracture incidence in the county of Ostergötland, Sweden, 1940-1986, with forecasts up to the year 2000: an epidemiological study.

The incidence of hip fractures in the county of Ostergötland in Sweden has increased dramatically from 1940 to 1986, mainly due to an increase in age-specific incidence of trochanteric fractures. The increase is most pronounced in people over 80 but is present even in age groups down to 50 years. If the age-specific incidence rates continue to increase, and the population of the elderly grows in accordance with the forecast, there will be 70% more hip fractures in the year 2000 than in 1985.

Age Factors↗
PubMed1991

Screening for carcinoma of the prostate in a randomly selected population using duplicate digital rectal examination.

Of 9,026 males, aged 50-69 years, 1,494 were randomly selected and invited to participate in a screening programme for carcinoma of the prostate. Of these 1,163 (78%) accepted. Rectal examination was performed independently by a general practitioner (GP) and by a urologist at the GP's surgery. Carcinoma of the prostate was suspected by one or both physicians in 45 cases, and subsequently confirmed by cytological investigation in 13 cases. Ten patients underwent radical prostatectomy, one received radiation treatment, one case was too advanced for curative treatment, and one was scheduled for subsequent reassessment. Screening, as a means of early diagnosis of carcinoma of the prostate by either a urologist or a GP, using digital rectal examination, thus appears to be a cost-effective procedure, though the question still remains whether this will lead to prolongation of survival or not.

Aged↗
PubMed1990

Screening for carcinoma of the prostate by digital rectal examination in a randomly selected population.

OBJECTIVE: To study the acceptability, costs, psychosocial consequences, and organisation of screening for carcinoma of the prostate. DESIGN: A randomly selected population was personally invited for digital rectal examination by a urologist and a general practitioner. Further examinations were performed if induration was felt. Each man completed a questionnaire on his response to the examination. SETTING: General practices in the area of Norrköping. PATIENTS: 1494 Men aged 50-69 randomly selected from a population of 9026. MAIN OUTCOME MEASURE: Prostates having a firm nodular consistency. RESULTS: Carcinoma of the prostate was suspected in 45 of 1163 patients examined; in 10 by the general practitioners, in 10 by the urologists, and in 25 by both. Forty four men had a fine needle aspiration biopsy, and carcinomas were found in 13 cases. Of these, one had been suspected by the general practitioner, four by urologists, and eight by both. The cost for each man was 11.60 pounds, and the cost for each case of carcinoma detected and treated by potentially curative methods was 2477 pounds. Of the 13 men with carcinoma, 10 underwent radical prostatectomy and one radiotherapy. One man had advanced disease and was given endocrine treatment, another was not treated. Only 193 men felt distress during the initial examination. Of the 44 men who had an aspiration biopsy, 25 experienced anxiety. CONCLUSIONS: Screening for carcinoma of the prostate by a urologist or a general practitioner using digital rectal examination is a cost effective method of early diagnosis. Whether such screening leads to prolonged survival, however, remains doubtful.

Aged↗
PubMed1989

[Prostatic cancer screening by rectal palpation can be organized with consideration to cost effectiveness].

Of 9,008 males, aged 50-69 years, 1,494 were randomly selected and invited to participate in a screening programme for carcinoma of the prostate; 1,163 (78 per cent) accepted. Rectal examination was performed independently by a GP and by a urologist at the GP's surgery. Carcinoma of the prostate was suspected by one or both physicians in 45 cases, and subsequently confirmed by cytological investigation in 13 cases. Ten patients underwent radical prostatectomy, one received radiation treatment, one case was too advanced for curative treatment, and one was scheduled for subsequent reassessment. Screening for early diagnosis of carcinoma of the prostate either by a urologist or by a GP, using digital rectal examination, would thus appear to be a cost-effective procedure, though the question remains whether it will promote prolongation of survival.

Aged↗
PubMed1987

Alkylating cytostatic treatment in renal amyloidosis secondary to rheumatic disease.

Fourteen consecutive patients with chronic inflammatory rheumatic disease and reactive renal amyloidosis were treated with alkylating cytostatics in 22 separate periods varying in duration between six and 30 months. Chlorambucil alone was given in 14 treatment periods, cyclophosphamide alone in six, and both alternately in two. The dosage was adjusted to attain a major suppression of the rheumatic inflammation and a blood lymphocyte level below 1.0 X 10(9)/l. Renal function improved in 12 treatment periods, renal deterioration was arrested in three periods, and in another four periods the rate of functional decline slowed down. In the remaining three treatment periods, associated with further deterioration in renal function, treatment was inadequate owing to blood dyscrasia and failure to control hypertension. Glomerular filtration rate (GFR) was followed more closely in 10 treatment periods, in all of which the falling trend was arrested or reduced. The survival rate at five years was 93%. Three patients who dropped out of the treatment programme are so far the only ones not still alive. Nine are still being followed up after 6-17 years, and the other two remaining live patients have had renal transplants for five years.

Adult↗