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Biomedical subjects

G Berg

Publications and source records attributed to G Berg.

At least 127 records · Page 7Linked to original sources
PubMed1995

[Low density lipoprotein rich in triglycerides and hepatic lipase activity in insulin-dependent diabetic patients].

Genetic hepatic lipase (HL) deficiency is associated with low density lipoprotein (LDL) rich in triglycerides (TG), whose affinity for B:E receptors is decreased. In rats, experimental hypoinsulinemia produces HL deficiency. However, the relation between human insulin-dependent Diabetes Mellitus (IDDM), HL activity and the characteristics of LDL have not been studied. The objective of our study is to evaluate the relation between HL activity and the chemical composition of LDL in treated IDDM patients. Subjects were 15 IDDM patients and 15 controls (C), matched for sex and body mass index (BMI). The IDDM patients were classified by the WHO criteria, were free of nephropathy and hypothyroidism, and received no medication except insulin. Controls were clinically healthy and normolipidemic with no family history of diabetes. The IDDM group was divided into two subgroups: subgroup IDDM-A (n = 9) with HL values > or = 4.3 and IDDM-B (n = 6) with HL < or = than 4.2 mumoles glycerol/ml h. the HL in IDDM was lower than in C (p < 0.001). Table 1 shows clinical data. Blood samples were drawn after 12 h fasting. Percentage of HbA1c and plasma concentrations of glucose, total cholesterol, LDL-cholesterol, HDL-cholesterol and TG were assayed. LDL was separated by sequential ultracentrifugation at densities of 1.019-1.063 g/ml and its chemical composition was analyzed. The most relevant results were: plasma TG concentration was higher in IDDM than in C (p < 0.05) (Table 2), although average values DMID not exceed the reference values of 200 mg/dl. The TG-LDL were higher in IDDM than in C: 24.8 +/- 2.7 vs 17.5 +/- 1.1 mg/dl plasma, media +/- SE, (p < 0.02). This difference reflected the values of IDDM-B, whose plasma concentrations of TG-LDL were higher than in C: 32.3 +/- 3.6 vs 17.5 +/- 1.1 mg/dl (p < 0.001), and also higher than in IDDM-A (p < 0.02). (Table 3). The chemical composition of LDL in IDDM-B contained a higher percentage of TG than C: 8.5 +/- 0.7 vs 6.8 +/- 0.3% (p < 0.05), a lower percentage of cholesterol than IDDM-A: 39.0 +/- 1.7 vs 45.2 +/- 2.2% (p < 0.05) and also a larger percentage of proteins than IDDM-A: 28.9 +/- 1.9 vs 20.8 +/- 1.0% (p < 0.01). The correlations between TG/cholesterol and HL activity in IDDM were r = -0.53 (p < 0.05) and in IDDM-B, r = -0.81 (p = 0.05). The noteworthy result of this study is the modification of the LDL particle in IDDM, rich in TG in patients with low HL activity. Anomalies in the chemical composition of LDL like those described decrease the uptake of this particle by its physiological B:E receptors. It has recently been demonstrated that LDL is an indisoluble association of lipids and apoproteins, and that both act simultaneously to hold the apoB in a spatial position that expresses normal epitopes. It has been described that particles of LDL rich in TG and poor in cholesterol, shows low affinity for LDL receptors in human fibroblasts. Also in IDDM the interaction of LDL rich in TG with B:E receptors is decreased. This might be one more mechanism contributing to the accelerated atherosclerosis of these patients. Our results suggest that there may be a threshold of HL activity for the complete hydrolysis of the TG of LDL, for the normalization of the TG/cholesterol relation and for the conformation of typical LDL particles.

Adult↗
PubMed1994

Clinical use of laboratory thyroid tests and investigations.

Laboratory thyroid testing involves in vitro tests for autoimmune thyroid disease, thyroid dysfunction and neoplasia, in vivo investigations of thyroid function, and investigations of thyroid morphology. The authors describe, in tabular form, the diagnostic information carried by the tests and their clinical utility as well as clinically relevant interferences.

Adult↗
PubMed1993

Maternal respiratory function following normal vaginal delivery.

Forced expiratory volume (FEV(1)) forced vital capacity (FVC), peak expiratory flow (PEF) and maximum expiratory pressure (P(E)max) were measured in 11 healthy women 2, 4, 8, 24, 48 and 72 hours after normal vaginal delivery and repeated after 6-8 weeks. There was a significant (P<0.05) reduction in the P(E)max up to 4 hours after delivery. In contrast, there was no significant reduction in FEV(1) or FVC at any of the time periods, and PEF showed a significant reduction only at 2 hours after delivery. This indicates that P(E)max is a more sensitive measure of respiratory muscle strength and that this is reduced for at least 4 hours after delivery. Any anaesthetic given during this period should take into consideration that the ability to cough effectively may be impaired.

Journal Article↗
PubMed1993

Overweight--a common problem among women treated for hyperthyroidism.

We sent out a questionnaire to 112 women treated for diffuse toxic goitre 2-5 years earlier to evaluate the prevalence of problems with overweight after the disease. Of 87 responders, about 50% (irrespective of surgical or radioiodine treatment) reported weight problems, and we randomly selected 40 of these women (20 with and 20 without reported weight problems) for a clinical follow-up (32 appearing). At the follow-up examination (mean 4 years after treatment for hyperthyroidism), 27 women had a higher weight than their estimated premorbid weight. The weight gain correlated with the estimated premorbid body mass index (BMI; P < 0.005), indicating that excess weight gainers may have had a premorbid problem now exaggerated in the post-hyperthyroid period. However, many women with a BMI within the limits stated to be ideal (21-25 kg/m2) also showed dramatic increases in weight. In contrast, the average middle-aged woman in our region did not appear to have gained in weight during a corresponding time period as judged from a longitudinal population study. Women with reported weight problems (mean weight increase 15.6%, n = 16) did not differ from women without (mean weight increase 6.7%, n = 16) as regards pretreatment hormone levels, method of treatment, (change of) smoking habits or post-treatment levothyroxine administration, or in serum concentrations of thyroid hormones, thyrotrophin, cortisol, procollagen-III-peptide, cholesterol, HDL cholesterol or triglycerides. Women with hyperthyroidism should be informed about the risk of gaining weight after therapy and given early support as to dietary and lifestyle change.

Adult↗
PubMed1993

Alpha-adrenergic receptors in human myometrium: changes during pregnancy.

Myometrial biopsies from 80 women, delivered by cesarean section in 26-42 completed weeks of pregnancy, were analyzed using radiolabeled alpha 1-antagonist [3H]-prazosin and alpha 2-antagonist [3H]-rauwolscine. Statistical analysis was performed using Student's t test (two-tailed), where p < 0.05 was considered significant. The number of alpha 2-adrenergic receptors did not vary (mean value weeks 37-39 = 17.2 +/- 1.3 fmol/mg protein), while the dissociation constant (Kd) for alpha 2-receptors tended to increase with increasing gestational age, implying reduced affinity near term (p < 0.05, mean values 3.4 +/- 0.2 nM). alpha 1-Receptors, however, increased significantly (p < 0.01) in the pregnancy weeks 37-39 (mean value 29.2 +/- 2.9 fmol/mg prot) while Kd was unaltered. Increased number of alpha 1-receptors, along with a decreased affinity of alpha 2-receptors, could, in combination with other factors, play a role in the initiation of labor.

Analysis of Variance↗
PubMed1993

Hormonal replacement therapy and sexuality in a population of Swedish postmenopausal women.

All women (n = 2465) living in the community of Linköping, Sweden, aged 55, 57, 59 and 65 years were studied in a cross-sectional trial concerning the prevalence of vasomotor symptoms, hormonal replacement therapy (HRT) and sexual activities. After one reminder, answers were received from 1867 (76%) women. In all, 51% of the women reported vasomotor symptoms. Ten percent of the women used HRT at the time of the survey. Another 10% of the women had previously used oral HRT but had abandoned treatment. One third of these women reported no vasomotor symptoms when they abandoned treatment. One fifth ceased treatment after recommendation from their physician and another fifth because of 'fear' of hormonal treatment. Sixty-two percent of the women reported sexual activity. The most common reasons for not having a regular sex-life were lack of partner or lack of desire.

Adult↗
PubMed1993

Automatic derivation of substructures yields novel structural building blocks in globular proteins.

Because the general problem of predicting the tertiary structure of a globular protein from its sequence is so difficult, researchers have tried to predict regular substructures, known as secondary structures, of proteins. Knowledge of the position of these structures in the sequence can significantly constrain the possible conformations of the protein. Traditional protein secondary structures are alpha-helices, beta-sheets, and coil. Secondary structure prediction programs have been developed, based upon several different algorithms. Such systems, despite their varied natures, are noted for their universal limit on prediction accuracy of about 65%. A possible cause for this limit is that traditional secondary structure classes are only a coarse characterization of local structure in proteins. This work presents the results of an alternative approach where local structure classes in proteins are derived using neural network and clustering techniques. These give a set of local structure categories, which we call Structural Building Blocks (SBBs), based upon the data itself, rather than a priori categories imposed upon the data. Analysis of SBBs shows that these categories are general classifications, and that they account for recognized helical and strand regions, as well as novel categories such as N- and C-caps of helices and strands.

Cluster Analysis↗
PubMed1992

Plasma lipid and lipoprotein effects of transdermal administration of estradiol and estradiol/norethisterone acetate.

To evaluate the effect of transdermal sequential treatment with estradiol and estradiol/norethisterone acetate on lipoprotein metabolism, 25 postmenopausal women received treatment for 12 cycles of 4 weeks each (2 weeks estradiol 50 micrograms/day and 2 weeks a combined patch delivering norethisterone acetate 0.25 mg/day and estradiol 50 micrograms/day). Blood samples for lipoprotein analyses were drawn before treatment and in estrogen and combined phases in cycles 3 and 12. Plasma total cholesterol, low (LDL) and high (HDL) density lipoprotein were all significantly reduced in both estrogen and combined phases. Eighteen of the women continued the treatment for 36 cycles. In this group the HDL-cholesterol had returned to baseline values in combined phase in cycle 24. Plasma cholesterol and LDL-cholesterol values remained significantly reduced throughout the whole study compared to the pre-trial values. The present study by transdermal sequential hormonal treatment results in a lipid and lipoprotein pattern with reduced total cholesterol and LDL cholesterol in postmenopausal women.

Administration, Cutaneous↗
PubMed1992

Leukaemia incidence after iodine-131 exposure.

Leukaemia is one of the most prominent late effects of exposure to ionising radiation. We have studied the incidence of leukaemia among 46,988 Swedish patients exposed to iodine-131 (131I) for diagnostic reasons or to treat hyperthyroidism or thyroid cancer. The observed number of leukaemias was compared with that expected based on incidence data from the general population. The mean absorbed dose to the bone marrow was estimated as 14 mGy (range 0.01-2.226). 195 leukaemias occurred more than 2 years after exposure, and the standardised incidence ratio (SIR) was 1.09 (95% confidence interval 0.94-1.25). Similar, but again not significantly, increased risks were seen for chronic lymphocytic leukaemia (CLL) (SIR = 1.08), a malignant condition not found to be increased after irradiation, and for non-CLL (SIR = 1.09). The risk of leukaemia did not vary by sex, age, time, or radiation dose from 131I. One reason for the absence of a radiation effect, other than chance, includes the possible lowering of risk when exposure is protracted over time as occurs with 131I. Excess leukaemia risks of more than 25% could thus be excluded with high assurance in this population of mainly adults. These results should be reassuring to patients exposed to 131I in medical practice and to most individuals exposed to the fall-out from the Chernobyl accident.

Adolescent↗
PubMed1992

Cancer mortality after iodine-131 therapy for hyperthyroidism.

Cancer mortality was studied in 10,552 Swedish hyperthyroid patients treated with 131I between 1950 and 1975. The patients were matched with the Swedish Cause-of-Death Register and the cases of 977 patients who died from cancer or leukemia were studied. The patients had been followed up for an average of 15 years (range 0 to 35 years), and the overall standardized mortality ratio (SMR) was 1.09 [95% confidence interval (CI) = 1.03 to 1.16], with a higher risk for women. The highest mortality was seen during the first year after exposure (SMR = 1.15) and decreased for the following 9 years (SMR = 1.04). The risk of dying from a cancer in the digestive tract and respiratory organs was significantly elevated more than 10 years after exposure, as was the overall cancer mortality (SMR = 1.14). No increased risk was seen for leukemia, bladder cancer or breast cancer. Younger patients and those receiving 131I at higher activity had higher SMRs than older patients and those receiving lower activity. Patients with toxic nodular goiter had higher risk than those with Graves' disease. The lack of increasing mortality over time and with increasing activity of 131I administered argues against a carcinogenic effect of 131I. However, in the case of cancers of the stomach, the 131I exposure could have contributed to the excess mortality from these cancers.

Age Factors↗
PubMed1992

[Cardiac function and the skin microcirculation in acromegaly].

The microcirculation was measured by nail-fold capillary video microscopy in 21 patients (12 men, 9 women; mean age 54.7 [29-74] years) with acromegaly. Levels of growth hormone (12.0-71.7 microU/ml) and of somatomedin C (2.4-10.5 IU/ml) were elevated in 10 patients, despite preceding treatment. Eleven patients had an increase in myocardial thickness and nine had impairment of left ventricular function, although only slight in most. Left ventricular hypertrophy was demonstrable even in the absence of hypertension. No patient had evidence of coronary heart disease. Nail-fold capillary video microscopy (capillary density, torque index, reactive hyperaemia, epidermal blood flow) failed to distinguish between successfully treated patients and those with persistently elevated growth hormone concentrations or disease duration of over 5 years. There was no evidence of inadequate capillary blood flow as a cause of abnormal function in hypertrophied organs.

Acromegaly↗
PubMed1992

Endometrial effects of transdermal estradiol/norethisterone acetate.

The efficacy of transdermal norethisterone acetate in sequence with transdermal estradiol has been investigated in a multicenter study of 136 post-menopausal women to determine the incidence of endometrial hyperplasia, the effects on the vaginal cytology and the control of bleeding. Treatment consisted of 12 cycles of 4 weeks each (2 weeks estradiol 50 micrograms/day followed by 2 weeks of a new combined patch delivering norethisterone acetate 0.25 mg/day and estradiol 50 micrograms/day). Endometrial histology was assessed by two pathologists. Of the 136 pre-treatment biopsies 89% provided no material, an inadequate sample or an inactive (atrophic or non-secretory) endometrium. Of the post-treatment biopsies from 110 women who completed the study: 65% showed secretory, 3% proliferative and 24% inadequate material or inactive endometrium. Hyperplasia was found in two biopsies (2%); in one of these focal atypical hyperplasia was agreed by both pathologists, in another a hyperplastic endometrial polyp was diagnosed by one pathologist. The bleeding was regular in 80% of the 1195 cycles and irregular in 11%. No bleeding occurred in 9% of the cycles. Vaginal cytology showed a significant shift towards increased maturation during treatment.

Administration, Cutaneous↗
PubMed1992

Long-term effect of transdermal hormonal therapy on aspects of quality of life in postmenopausal women.

The long-term effect on aspects of quality of life (QoL) of treatment with transdermal oestrogen for 2 weeks followed by transdermal oestrogen/progestogen norethisterone acetate/oestradiol TTS 0.25/0.05 mg/day for the next 2 weeks was investigated in postmenopausal women within the framework of a 1-year seven-centre trial. Of the 136 women who were included (mean age 53 +/- 4.8 years), 110 completed the study. Aspects of QoL that are of relevance in the perimenopause and postmenopause were evaluated using the Psychological General Well-Being (PGWB) index, the Women's Health Questionnaire (WHQ) and the Sleep Dysfunction Scale before and after 3 and 9 months of therapy in the oestrogen phase. Climacteric complaints were also assessed by means of the Kupperman Index. Improved well-being, i.e. less anxiety and depression, increased vitality and better self-control (P less than 0.0001) were observed, as well as reduced sleep disturbance (P less than 0.0001). The WHQ showed decreased vasomotor and somatic symptoms, and improved sex life, emotions and cognitive function (P less than 0.0001). Improvement was the same at 3 and 9 months. According to the Kupperman Index, climacteric symptoms were alleviated (P less than 0.0001). Relief of vasomotor symptoms was correlated with improvement in the WHQ (r = 0.82), the PGWB index (r = 0.58, P less than 0.0001) and sleep (r = 0.51, P less than 0.0001). Because of the absence of a placebo control group, the results must be regarded with caution until confirmed in a placebo-controlled trial.

Administration, Cutaneous↗
PubMed1992

Spinal or epidural anaesthesia for elective caesarean section? A Swedish experience.

Ninety seven women undergoing elective lower segment caesarean section were randomly divided into two groups, group 1 received spinal anaesthesia with hyperbaric bupivacaine and group 2 received mepivacaine 20 mg/ml with adrenaline 5 microg/ml via an epidural catheter. All patients were given a preload of Ringer acetate and Macrodex prior to onset of anaesthesia. Ephedrine 5 mg was given if the systolic blood pressure fell below 100 mmHg. There was a small (<30%) but significant (P<0.01) fall in blood pressure in both groups of women. Six women in the epidural group required supplemental analgesics during the operation compared to only 1 patient in the spinal group (P<0.01). Muscle relaxation was judged to be inadequate in 3 patients in the spinal group and in 5 patients in the epidural group. One patient in the spinal group had a characteristic post-spinal headache lasting 3 days. The injection-delivery time was shorter (P<0.01) in the spinal group compared to the epidural group. The Apgar scores at 1 and 5 min were similar in both groups. The results from our study suggest that spinal anaesthesia is a good alternative to epidural anaesthesia for elective caesarean section. A fall in blood pressure, which is equally possible in both groups of patients, should be prevented by adequate fluid preload and treated immediately by intravenous ephedrine.

Journal Article↗