Biomedical subjects

E Lund

Publications and source records attributed to E Lund.

At least 91 records · Page 5Linked to original sources

PubMed1999

Studies in hypertriglyceridaemia. VI: Serum lathosterol concentration is raised in hypertriglyceridaemic non-diabetic males with hyperinsulinaemia.

OBJECTIVES: To assess the cholesterol synthesis rate in primary hypertriglyceridaemia using the serum unesterified lathosterol concentration as an indicator. DESIGN: A cross-sectional, case-control study. SETTING: The Karolinska Hospital, Stockholm. SUBJECTS: Randomly selected hyper- (n = 53) and normotriglyceridaemic (n = 57) males, 40-50 years, with a fasting serum triglyceride concentration (mean +/- SD) of 3.81 +/- 1.65 and 1.28 +/- 0.53 mmol L-1, respectively. The exclusion criterion was diabetes mellitus, defined according to the World Health Organization (WHO) guidelines. MAIN OUTCOME MEASURES: To compare the fasting serum concentration distributions of lathosterol, a cholesterol precursor, in hyper- and normotriglyceridaemic groups. RESULTS: Thirty-six per cent of the hypertriglycerdaemic group had raised serum lathosterol concentrations, based on the 90th percentile of the lathosterol distribution of the normotriglyceridaemic group. In the hyper- but not in the normotriglyceridaemic group, lathosterol concentration was directly correlated with serum insulin responses to oral (r = 0.38; P = 0.007) and intravenous (r = 0.41; P = 0.005) glucose challenges. CONCLUSIONS: One-third of a randomly selected non-diabetic hypertriglyceridaemic population had an increased serum lathosterol concentration and this might indicate an increased cholesterol synthesis rate compatible with increased production of VLDL particles, possibly as the result of chronic hyperinsulinaemia.

Adult↗

PubMed1999

Future demand for dental care in Norway; a macro-economic perspective.

The future demand for dental care in Norway is discussed on the basis of economic theory. During the next 30 years gross national income will increase substantially due to a marked increase in national income from the sale of oil and gas. On the basis of the model we predict that this increase in income will lead to an increase in demand for dental services in the short run, say for the next 10-15 years. To a large extent this increase in demand is supported by evidence from dental epidemiology. In particular, an increasing proportion of elderly dentate people will demand more services. This picture is different in the long run, say from the year 2010-15 and onwards. Evidence from dental epidemiology indicates that at that stage there will be a fairly high proportion of disease-free individuals in the population who will demand less dental care. Such a trend is also supported by economic theory as long as disease-free individuals consume less dental care irrespective of their income.

Cost Control↗

PubMed1999

Self-reported ethnic status of delivering women, newborn body mass index, blood or urine concentrations of toxic metals, and essential elements in sera of Norwegian and Russian Arctic populations.

UNLABELLED: As part of the Arctic Monitoring and Assessment Programme (AMAP), we assessed pregnancy outcome among Sami and Norwegian populations of Finnmark County in Norway and Russians living in the Kola Peninsula of Russia using body mass index of the newborn child (BMIC) as the main indicator; concentrations of essential and toxic elements in biological fluids of delivering women and their children served as additional sources of information. At the hospitals of Hammerfest and Kirkenes in the period November 1993-June 1994 a total of 107 consecutive women gave birth to a child, of whom 15 regarded themselves as Sami. The Russian group (N = 151) delivered their children in the same period. The Sami women were significantly older than the Russian group (28.5 versus 25.1 years, p = 0.04). The mean birth weight was significantly lower in the Sami group compared to non-Sami Norwegians (p = 0.01), but was of comparable magnitude to that recorded in Russia (p = 0.4). For BMIC, the Sami and non-Sami Norwegian results were similar (p = 0.2); both were significantly higher than in Russia (p < 0.001). The essential elements copper, zinc, selenium and iron (as ferritin) in serum showed no differences between the groups, although relatively low levels of serum zinc were documented in all populations studied. Blood cadmium concentrations were strongly related to smoking frequency. Blood lead and urinary nickel levels were significantly higher for the Russian mothers, but did not reach levels of medical concern. CONCLUSION: No ethnic differences in concentrations of essential elements in biological fluids, nor of cadmium and mercury, were observed. However, national differences for lead and nickel were evident. Because of small sample size, these conclusions need confirmation. The similar BMIC values observed for the non-Sami Norwegian and Sami newborns, compared to the Russian group, suggest that BMIC may serve as a good indicator of the nutritional status and possibly also the general health condition of neonates.

Adolescent↗

PubMed1999

Mink enteritis parvovirus. Stability of virus kept under outdoor conditions.

Feces from mink with acute mink enteritis were pooled and then allowed to dry out in open tubes kept under a roof in an open shed for one year starting in January. Samples of feces were harvested approximately once a month. These were reconstituted to their original volume and tested for antigen content and infectivity both in in vitro cell cultures and - on selected samples - in vivo. During the first 8 months, the antigen level in the feces samples decreased slowly. At this time point, a plateau was reached at 30-40% of the original viral antigen contents. The infectivity in vitro was unchanged for the first 5 months, but after mid-summer it decreased abruptly to below the detection level. Based on the in vitro infectivity, 10 samples were selected for inoculation into mink to measure the in vivo infectivity. The transmission of the infection to the experimental animals was successful for all samples showing infective virus by cultivation. In addition, it was possible to infect mink using material harvested one month after the cell culture test had turned negative. One mink inoculated with material collected in October excreted virus. We conclude that parvovirus can survive for at least 5-10 months (or during the winter period) under natural conditions, but complete drying out seems to lead to its inactivation. Mechanical cleaning of the premises is thus as critical as disinfection since virus can only survive the dry summer period if protected by protein or buried in moist soil on the premises.

Animals↗

PubMed1999

Concentrations of essential trace elements in maternal serum and the effect on birth weight and newborn body mass index in sub-arctic and arctic populations of Norway and Russia.

BACKGROUND: This project is part of an assessment of the impact of environmental factors on human health in the Kola Peninsula of Russia and the neighboring arctic area of Norway. Pregnant women and their newborns were studied to explore a relationship between maternal status of essential metals and birth weight. METHODS: Life-style information and serum specimens were collected from at least 50 consecutive mother-infant pairs from hospital delivery departments in three Russian and three Norwegian communities (N=151 and 167, respectively). Pregnancy outcomes were verified by consulting medical records. Copper, selenium and zinc in serum were determined by atomic absorption spectrometry and ferritin by an automated analyzer method. RESULTS: Mean birth weight and child's body mass index (BMIC) were significantly lower in the Russian group (p<0.001), with or without adjustment for gestational age. Copper, iron (as ferritin) and selenium serum concentrations were in the normal range, while zinc levels in both countries were mostly below the lower limit (10.8 micromol/L) of reported reference intervals. A positive correlation between zinc and birth weight or BMIC was only observed for concentrations exceeding 10.8 micromol/L. Analysis by quartiles showed that maternal urinary creatinine and birth weight were negatively correlated (p=0.001). The influence of the different elements on BMIC, grouped by quartiles, was significantly positive only for selenium (p=0.03) and ferritin (p=0.02), while there was no significant relationship for copper or zinc. Adjustment of birth weight and BMIC for gestational age did not alter substantially the various associations indicated. CONCLUSIONS: With the exception of zinc, the mineral status of delivering women in arctic and sub-arctic regions of Norway and western Russia appears to be adequate. The significantly lower BMIC for the Russian group suggests the likely occurrence of nutritional deficiencies during pregnancy in Russia. However, the significant contribution of a country factor in the predictive model implies that the maternal serum trace-element concentrations explored in this study are incomplete indicators of fetal undernourishment.

Adult↗

PubMed1999

Blood lead and cadmium and birth weight among sub-arctic and arctic populations of Norway and Russia.

BACKGROUND: Delivering women and their newborns in the Kola Peninsula of Russia and the neighboring arctic area of Norway were studied to explore relationships between maternal cadmium and lead status and birth weight as a pregnancy outcome. METHODS: Life-style information, maternal blood and cord blood specimens were collected from 50 consecutive mother-infant pairs from hospital delivery departments in three Russian and three Norwegian communities. Pregnancy outcomes were verified by consulting medical records. Lead and cadmium were determined in the blood samples by electrothermal atomic absorption spectrometry. RESULTS: The median blood-cadmium concentration for the Russian mothers was 2.2 nmol/L (n = 148) versus 1.8 nmol/L in the Norwegian group (n = 114, p = 0.55). A weak association was observed between maternal cadmium and amount smoked (r = 0.30, p<0.001); no correlation was found between maternal blood cadmium and birth weight. The corresponding maternal lead values were 0.14 (Russia) and 0.06 micromol/L (Norway), p<0.001. The latter lead concentration constitutes one of the lowest adult population values reported to date. Maternal and cord blood lead levels were strongly correlated (r = 0.88, p<0.001). In a multivariate linear regression model, maternal blood lead was recognized as a negative explanatory variable (p<0.05) for birth weight and child's body mass index (BMIC), with or without adjustment for gestational age. A similar association was suggested by ANOVA-analysis of maternal blood lead by quartiles. CONCLUSION: Maternal blood-lead level as an environmental factor is an apparent predictor of low birth weight and BMIC. It reduced substantially the contribution of a country factor in explaining the observed differences in birth weight.

Adult↗

PubMed1998

Proofreading and aminoacylation of tRNAs before export from the nucleus.

After synthesis and processing in the nucleus, mature transfer RNAs (tRNAs) are exported to the cytoplasm in a Ran.guanosine triphosphate-dependent manner. Export of defective or immature tRNAs is avoided by monitoring both structure and function of tRNAs in the nucleus, and only tRNAs with mature 5' and 3' ends are exported. All tRNAs examined can be aminoacylated in nuclei of Xenopus oocytes, thereby providing a possible mechanism for functional proofreading of newly made tRNAs. Inhibition of aminoacylation of a specific tRNA retards its appearance in the cytoplasm, indicating that nuclear aminoacylation promotes efficient export.

Acylation↗

PubMed1998

[Significance of migration patterns on self-evaluated health among Norwegian women aged 34-69 years].

In order to study how internal migration effects the evaluation of one's health, information was collected by a postal questionnaire from a total of 75,750 women during 1991-1992 (34-49 years) and 1995-1996 (45-69 years). The women were selected at random from the Norwegian National Register. All the women were sent a questionnaire and one reminder. The overall response rate was 56.5%, decreasing with increasing age. Women who had lived in the same area since childhood were considered "non-movers", while those who lived in a different area to where they grew up were classified as "internal movers". We found that among people who were brought up and still lived in northern Norway there was a higher rate of their reporting poor or very poor health than among "non-movers" in southern Norway. The adjusted relative rate was 1.39 (1.29-1.49). The reason for the higher rates could be semantic differences, more actual illness, or the effect of selective migration of healthy individuals out of the region of northern Norway.

Adult↗

PubMed1998

[Mortality resulting from femoral neck fractures in Norway 1980-94].

Based on information obtained from the central register of death certificates held by the Norwegian National Bureau of Statistics trends in mortality resulting from fractura colli femoris were analysed for the period 1980-94. Mortality decreased by 30% (95% CI; 26%-34%) among women aged 60-98 years, whereas it remained constant among men. For both genders the risk of death from fractura colli femoris increased with age by approximately 20% per year. These changes are discussed in relation to the alleged epidemic of fractura colli femoris.

Aged↗

PubMed1998

Functions of the GTPase Ran in RNA export from the nucleus.

Significant and exciting advances in the field of RNA and protein export have been made recently, due in large part to discovery of the roles played by Ran, a small, soluble GTPase present in both the nucleus and cytoplasm of all eukaryotic cells. Ran is thought to be primarily bound to GTP in the nucleus and to GDP in the cytoplasm, as a result of the assymetric distribution of factors that interact with Ran to promote guanine nucleotide exchange (in the nucleus) and GTP hydrolysis (in the cytoplasm). A key function of the nuclear Ran.GTP is to support formation of complexes containing an export receptor (an exportin) and cargos such as RNAs, RNPs or proteins that are destined for export. In the cytoplasm, removal of the Ran.GTP from the complex results in its destabilization and release of the export cargo. Although Ran.GTP is required for formation of the export complex, GTP hydrolysis does not appear to be necessary for translocation through the nuclear pore complex or cytoplasmic release. Nevertheless, the GTPase of Ran does appear to be required in as yet unidentified intranuclear steps prior to export of some, but not all, RNAs.

Animals↗

PubMed1998

Self-reported mental distress under the shifting daylight in the high north.

BACKGROUND: The validity of the concept of seasonal affective disorder and the causal link to lack of daylight in winter is controversial. There is a need for investigations in large samples of the general population at different latitudes and within general research contexts to avoid selective response bias and sensitization of the population. METHODS: During a study of health effects of the air pollution from Russia in a small community at 70 degrees north, a self-administered questionnaire was filled in by 3736 inhabitants, 60.8% of the total population between 18 and 69 years. Three questions concerned depression, sleeping problems and other problems related to the two contrasting seasons with regard to daylight. RESULTS: Twenty-seven per cent reported to have some kind of problem in the dark period. Most frequently reported were sleeping problems during winter, in 19.9% of women and 11.2% of men. Self-reported depression in winter was found in 11.1% of women and 4.8%% of men. Sleeping problems increased with age, while depression was most often reported by middle-aged people. The only other reported problem in winter was fatigue. The adjusted relative risk (RR) for winter depression in women compared to men was 2.5 (95% confidence interval: 1.9-3.2). Very few had problems in summer. CONCLUSIONS: In the high north, one-third of the women and one-fifth of the men experience problems with sleep, mood or energy related to season. The prevalence of self-reported depression was surprisingly low in winter considering the lack of daylight.

Adult↗

PubMed1998

Relationship between dietary habits, age, lifestyle, and socio-economic status among adult Norwegian women. The Norwegian Women and Cancer Study.

OBJECTIVE: To examine how dietary intake varies with age in a nation-wide sample of adult Norwegian women, and to evaluate the impact of lifestyle and socio-economic status on important dietary aspects. DESIGN: Cross-section study. SETTING AND SUBJECTS: A food frequency questionnaire was mailed to a random, nation-wide sample of 20 000 women aged 45-69y, and 9885 questionnaires were accepted for nutritional analyses. RESULTS: Dietary habits differed moderately with age. The oldest women reported a higher consumption of potatoes and fish, whereas the youngest reported more coffee, meat, and alcohol. The reported intake of fruit, vegetables, and potatoes was lower than recommended in all age groups. Older women had a slightly better distribution of energy yielding nutrients than younger women, although the median percentage of energy from fat was too high in all age groups. The median dietary fibre density of the diet was close to the recommended level in all age groups, yet lowest among the youngest women. Practising a healthy lifestyle and having a higher socio-economic status were associated with reporting a healthier diet. However, adjusting for lifestyle and socio-economic factors did not substantially alter the associations between diet and age. CONCLUSIONS: Older women tend to have a healthier diet than younger women. The relationship does not seem to be strongly confounded by lifestyle and socio-economic status, although these factors are also related to dietary habits.

Aged↗

PubMed1998

Response rate according to title and length of questionnaire.

The purpose of this study was to investigate how response rates to a postal questionnaire are affected by title and length of the survey instrument. Five questionnaires, which differed according to title and length, were designed. Each questionnaire was mailed to a random sample of one thousand Norwegian women aged, 35-49 years. A total of 3,106 questionnaires were returned (62.1%). The highest response rate (70.2%) was achieved by a two-page questionnaire entitled "Women and Cancer". An otherwise identical questionnaire entitled "Oral Contraceptives and Cancer" had a response rate of 60.7%. Questionnaires entitled "Women and Cancer" with a length of four and six pages had a response rate of 62.8% and 63.3%, respectively. The four page questionnaire entitled "Women, Lifestyle and Health" had the lowest response rate of 57.1%. This study shows that in a general population of Norwegian women the title of a postal questionnaire influences the response rate. The results indicate that although the shortest questionnaire had the highest response rate, the most extensive survey instrument did not have the lowest response rate. The distribution of risk factors for breast cancer did not vary according to response rate or design of questionnaire. The overall findings of this study suggest that the benefits from the increased information obtained from extensive postal questionnaires out-weighs a potential non-response bias due to a somewhat lower response rate.

Adult↗

PubMed1998

Cancer patients use of nonproven therapy: a 5-year follow-up study.

PURPOSE: To investigate the prospective pattern of use of alternative medicine, here called nonproven therapy (NPT), among oncologic patients during a 5-year period, and the relationship between this use and survival, a questionnaire-based follow-up study was performed at the Department of Oncology, University of Tromsø, from 1990 to 1996. PATIENTS AND METHODS: Two-hundred fifty-two patients answered the first questionnaire during the period July 1990 to July 1991. Eligible patients were mailed follow-up questionnaires after 4, 12, 24 and 60 months. A telephone interview performed after the last follow-up questionnaire showed little disagreement with the prospective collected information as regards the number of patients reported as users of NPT (kappa, 0.92). RESULTS: The number of patients who reported ever using NPT in each cross-sectional part of the study varied between 17.4% and 27.3%. However, the estimated cumulative risk of being a user of NPT during the follow-up period was 45%. Seventy-four percent of NPT users in this north Norwegian study population used faith healing or healing by hand (spiritual NPT) alone or in combination with other forms of NPT. The proportion of patients who used spiritual versus nonspiritual forms of NPT was consistent throughout the follow-up period. Women were more often users than men (50% v 31%, P = .002). Patients older than 75 years of age seldomly used NPT. The 5-year observed survival rate was not influenced by the use of NPT. Adjusted for sex, age, and diagnosis, patients with a high educational level had a borderline higher 5-year survival rate than patients with less education (P = .06). CONCLUSION: Our results demonstrate that cross-sectionally designed studies will underestimate the number of ever-users of NPT in a cancer patient population. The use of NPT does not influence observed survival among cancer patients seen in north Norway.

Adolescent↗

PubMed1998

Urinary nickel excretion in populations living in the proximity of two russian nickel refineries: a Norwegian-Russian population-based study.

The Russian nickel refineries located in the cities of Nikel and Zapolyarny close to the Norwegian border are responsible for extensive sulfur dioxide and nickel pollution, as well as severe ecological damage in both countries. The aim of our study was to investigate human nickel exposure in the populations living on both sides of the Norwegian-Russian border. The design was a cross-sectional population-based study of adults aged 18-69 years residing in Sor-Varanger municipality, Norway, and Nikel and Zapolyarny, Russia, during 1994 and 1995. Individual exposure to nickel was assessed by measurements of nickel in urine using electrothermal atomic absorption spectrometry. For controls, urine was collected from adults in the Russian cities of Apatity and Umba (Kola Peninsula) and the Norwegian city of Tromso, all of which are locations without nearby point sources of nickel. Altogether 2,233 urine specimens were analysed for nickel. People living in Nikel had the highest concentrations (median 3.4 microg/l), followed by Umba (median 2.7 microg/l), Zapolyarny (median 2.0 microg/l), Apatity (median 1.9 microg/l), Tromso (median 1.2 microg/l), and Sor-Varanger (median 0.6 microg/l). Regardless of geographical location, the Russian study groups all had a higher urinary-nickel average than those in Norway (p<0.001). With the exception of Nikel, neither the Russian nor the Norwegian urinary-nickel levels were associated with residence location near a Russian nickel refinery. We concluded that industrial nickel pollution alone could not explain the observed discrepancy between Norway and Russia; we also discuss other possible nickel exposure sources that may account for the high urinary levels found in Russia.

Adolescent↗

PubMed1997

Inhibition of mRNA export in vertebrate cells by nuclear export signal conjugates.

Leucine-rich nuclear export signals (NESs) are recognized by the NES receptor exportin 1 and are central to the export of multiple shuttling proteins and RNAs. The export of messenger RNA in vertebrates was, however, thought to occur by a different pathway, because inhibition by injection of a synthetic Rev NES conjugate could not be demonstrated. Here we find that peptide conjugates composed of the NES of either protein kinase A inhibitor protein (PKI) or the HIV-1 Rev protein, when coupled to human serum albumin, are potent inhibitors of mRNA and small nuclear RNA export. These results provide direct evidence that mRNA export in vertebrates depends on interactions between an NES and its cognate NES receptors. PKI NES conjugates are significantly more efficient at inhibiting RNA export than are REV NES conjugates, indicating that different NESs may have different abilities to promote protein and RNA export. Surprisingly, an expected control conjugate containing the mutant Rev NES sequence M10 strongly inhibited the export of intronless dihydrofolate reductase mRNA. Nuclear injection of NES peptide conjugates led to mislocalization to the nucleus of 10-20% of the cytoplasmic Ran GTPase-binding protein (RanBP1) indicating that RanBP1 shuttles between the nucleus and the cytoplasm via an NES pathway. These results demonstrate that in vertebrates the export of mRNA, like that of small nuclear RNA, 5S rRNA, and transport factors such as RanBP1, employs NES-mediated molecular machinery.

Amino Acid Sequence↗

PubMed1997

The constitutive transport element (CTE) of Mason-Pfizer monkey virus (MPMV) accesses a cellular mRNA export pathway.

The constitutive transport elements (CTEs) of type D retroviruses are cis-acting elements that promote nuclear export of incompletely spliced mRNAs. Unlike the Rev response element (RRE) of human immunodeficiency virus type 1 (HIV-1), CTEs depend entirely on factors encoded by the host cell genome. We show that an RNA comprised almost entirely of the CTE of Mason-Pfizer monkey virus (CTE RNA) is exported efficiently from Xenopus oocyte nuclei. The CTE RNA and an RNA containing the RRE of HIV-1 (plus Rev) have little effect on export of one another, demonstrating differences in host cell requirements of these two viral mRNA export pathways. Surprisingly, even very low amounts of CTE RNA block export of normal mRNAs, apparently through the sequestration of cellular mRNA export factors. Export of a CTE-containing lariat occurs when wild-type CTE, but not a mutant form, is inserted into the pre-mRNA. The CTE has two symmetric structures, either of which supports export and the titration of mRNA export factors, but both of which are required for maximal inhibition of mRNA export. Two host proteins bind specifically to the CTE but not to non-functional variants, making these proteins candidates for the sequestered mRNA export factors.

Animals↗

PubMed1997

Elimination of cholesterol in macrophages and endothelial cells by the sterol 27-hydroxylase mechanism. Comparison with high density lipoprotein-mediated reverse cholesterol transport.

Cultured macrophages and endothelial cells have been reported to secrete 27-oxygenated metabolites of cholesterol. This mechanism was compared with the classical high density lipoprotein (HDL)-dependent reverse cholesterol transport. Under standard conditions, macrophage preparations had considerably higher capacity to secrete 27-hydroxycholesterol and 3beta-hydroxy-5-cholestenoic acid than had endothelial cells and fibroblasts. Western blotting showed that lung macrophages contained the most sterol 27-hydroxylase protein of the cells tested. The relative amounts of 3beta-hydroxy-5-cholestenoic acid produced by the macrophages were also highest. Macrophages derived from monocytes of patients with sterol 27-hydroxylase deficiency did not secrete 27-oxygenated products, demonstrating that sterol 27-hydroxylase is the critical enzyme for the conversion of cholesterol into the 27-oxygenated steroids. That sterol 27-hydroxylase is responsible not only for 27-hydroxylation of cholesterol but also for the further oxidation of this steroid into 3beta-hydroxy-5-cholestenoic acid was shown with use of tritium-labeled 27-hydroxycholesterol and an inhibitor of sterol 27-hydroxylase. Secretion of 27-oxygenated products by the cultured macrophages as well as the ratio between the alcohol and the acid appeared to be dependent upon total 27-hydroxylase activity, the availability of substrate cholesterol, and the presence of an acceptor for 27-hydroxycholesterol in the medium. With albumin as extracellular acceptor, the major secreted product was 3beta-hydroxy-5-cholestenoic acid. Under such conditions, secretion of labeled 27-oxygenated products was higher than that of labeled cholesterol from lung alveolar macrophages preloaded with [4-14C]cholesterol. With HDL as acceptor, 27-hydroxycholesterol was the major secreted product, and the total secretion of labeled 27-oxygenated products was only about 10% of that of labeled cholesterol. Thus, 27-hydroxycholesterol and cholesterol may compete for HDL-mediated efflux from the cells. The results support the contention that the sterol 27-hydroxylase-mediated elimination of cholesterol is more important in macrophages than in endothelial cells. This mechanism may be an alternative and/or a complement to the classical HDL-mediated reverse cholesterol transport in macrophages, in particular when the concentration of HDL is low.

Albumins↗