PubMed Health⌕ Search

Biomedical subjects

L Vatten

Publications and source records attributed to L Vatten.

At least 37 records · Page 2Linked to original sources
PubMed1999

Population density and childhood leukaemia: results of the EUROCLUS Study.

The EUROCLUS study assembled incidence data for 13,551 cases of childhood leukaemia (CL) diagnosed between 1980 and 1989 in 17 countries (or regions of countries). These were referenced by location at diagnosis to small census areas of which there were 25,723 in the study area. Population counts, surface area and, hence, population density were available for all these small areas. Previous analyses have shown limited extra-Poisson variation (EPV) of case counts within small areas; this is most pronounced in areas of intermediate population density (150-499 persons/km2). In this study, the data set was examined in more detail for evidence that variations in incidence and EPV of CL are associated with population density. Incidence showed a curvilinear association with population density and was highest in areas which were somewhat more densely populated (500-750 persons/km2), where the incidence rate ratio relative to areas having > or = 1000 persons/km2 was 1.16 (95% confidence interval 1.07-1.26) and the P value for quadratic trend across eight strata of population density was 0.02. Incidence in these areas is uniformly elevated and showed no evidence of heterogeneity (i.e. EPV). Statistically significant evidence of EPV was evident amongst some of the areas previously classified as intermediate density areas (specifically, those with a density of 250-499 persons/km2, P < 0.001 for CL). These results were interpreted in terms of the current aetiological hypotheses for CL which propose that exposure to localised epidemics of one or more common infectious agent may contribute to the development of leukaemia. They suggest that such epidemics arise regularly in moderately densely populated areas and also sporadically in areas which are somewhat less densely populated. Although other interpretations are possible, these results may assist in the identification of characteristics which infectious agents must possess if direct or indirect causes of CL.

Child↗
PubMed1998

[Female sex hormones increase the risk of breast cancer].

The incidence of breast cancer in women in increasing, partly due to changes in age distribution in the population, and partly due to a real increase in risk. Changes in family patterns may, to some extent, explain the increased risk since giving birth to a first child late in life and bearing few children both increase the risk of breast cancer. The influence of female sex steroids on the breast plays a central role, but the biological mechanism is not clearly understood. There is a certain amount of risk involved in using hormonal medication (oral contraceptives or postmenopausal hormone replacement), but on ceasing to take the medication, risk will revert to the expected rate within a few years. Future epidemiological research on breast cancer will concentrate on events occurring during hormonally potent phases of life, such as growth and development during the fetal period, and sexual and somatic maturation during adolescence. Until now only modest interest has been shown in researching these two particular phases, but both may be important for the natural course of breast cancer.

Adolescent↗
PubMed1998

Neuroendocrine differentiation in human gastric carcinoma.

BACKGROUND: Distinguishing between neuroendocrine carcinoma and adenocarcinoma may be difficult. METHODS: In the current prospective study blood and tumor tissue from patients with gastric carcinoma were collected. The tissue was fixed in different ways to allow examination for neuroendocrine markers by multiple methods such as various histochemical and immunohistochemical methods and electron microscopy. Blood and tumor homogenates were examined by radioimmunoassay for specific hormones and general neuroendocrine markers. RESULTS: Based on examination of general neuroendocrine markers such as chromogranin A (by immunohistochemistry, Northern blot analysis, and tissue concentration), neuron specific enolase (immunohistochemistry) as well as electron microscopy, it was possible to conclude that approximately 10% of the tumors were actually neuroendocrine malignant tumors. Among these tumors, the enterochromaffin-like (ECL) cell was the most preponderant cell of origin (Sevier-Munger positive and serotonin negative immunoreactive tumor cells with secretory granules resembling those observed in normal ECL-cells). As reported previously, tumors of the diffuse type (according to the classification of Laurén) most often were reclassified as neuroendocrine carcinomas. CONCLUSIONS: The current study shows that neuroendocrine and particularly ECL cell-derived tumors are more common in the stomach than previously recognized.

Adenocarcinoma↗
PubMed1998

Reduced production of PGE2 and PGF2 alpha from decidual cell cultures supplemented with N-3 polyunsaturated fatty acids.

A diet rich in n-3 polyunsaturated fatty acid (PUFA) may reduce the intrauterine production of prostaglandins and prolong pregnancy. We tested this hypothesis by assessing the influence of various PUFAs on the spontaneous production of PGE2 and PGF2 alpha from decidual cell cultures. In addition, we assessed prostaglandin and cytokine production stimulated by lipopolysaccharides (LPS) in order to mimic parturition where infection is involved. In both settings, we found that after supplementing with n-3 PUFA, PGE2 and PGF2 alpha were significantly reduced. After supplementing with n-6 PUFA, there was a significant increase in both prostaglandins. Both n-3 and n-6 PUFAs reduced the production of interleukin 1 (IL-1), while n-6 PUFAs reduced TNF production. PUFAs did not influence IL-6 production. Our findings support the hypothesis that dietary n-3 PUFA may prolong pregnancy by reducing intrauterine production of prostaglandins.

Cells, Cultured↗
PubMed1998

Spatial temporal patterns in childhood leukaemia: further evidence for an infectious origin. EUROCLUS project.

The EUROCLUS project included information on residence at diagnosis for 13351 cases of childhood leukaemia diagnosed in the period 1980-89 in defined geographical regions in 17 countries. A formal algorithm permits identification of small census areas as containing case excesses. The present analysis examines spatial-temporal patterns of the cases (n = 970) within these clustered areas. The objectives were, first, to compare these results with those from an analysis conducted for UK data for the period 1966-83, and, second, to extend them to consider infant leukaemias. A modification of the Knox test investigates, within the small areas, temporal overlap between cases in a subgroup of interest at a putative critical time and all other cases at any time between birth and diagnosis. Critical times were specified in advance as follows: for cases of acute lymphoblastic leukaemia aged 2-4 years, the 18-month period preceding diagnosis; for cases of total leukaemia aged 5-14 years, 1 year before to 1 year after birth; and for infant cases (diagnosed < 1 year), 1 year before to 6 months after birth. Each of the analyses found evidence of excess space-time overlap compared with that expected; these were 10% (P = 0.005), 15% (P= 0.0002) and 26% (P= 0.03) respectively. The results are interpreted in terms of an infectious origin of childhood leukaemia.

Adolescent↗
PubMed1998

Spatial clustering of childhood leukaemia: summary results from the EUROCLUS project.

The interpretation of reports of clusters of childhood leukaemia is difficult, first because little is known about the causes of the disease, and second because there is insufficient information on whether cases show a generalized tendency to cluster geographically. The EUROCLUS project is a European collaborative study whose primary objective is to determine whether the residence locations of cases at diagnosis show a general tendency towards spatial clustering. The second objective is to interpret any patterns observed and, in particular, to see if clustering can be explained in terms of either infectious agents or environmental hazards as aetiological agents. The spatial distribution of 13351 cases of childhood leukaemia diagnosed in 17 countries between 1980 and 1989 has been analysed using the Potthoff-Whittinghill method. The overall results show statistically significant evidence of clustering of total childhood leukaemia within small census areas (P=0.03) but the magnitude of the clustering is small (extra-Poisson component of variance (%) = 1.7 with 90% confidence interval 0.2-3.1). The clustering is most marked in areas that have intermediate population density (150-499 persons km[-2]). It cannot be attributed to any specific age group at diagnosis or cell type and involves spatial aggregation of cases of different ages and cell types. The results indicate that intense clusters are a rare phenomenon that merit careful investigation, although aetiological insights are more likely to come from investigation of large numbers of cases. We present a method for detecting clustering that is simple and readily available to cancer registries and similar groups.

Adolescent↗
PubMed1998

TNF, IL-1, IL-6, IL-8 and soluble TNF receptors in relation to chorioamnionitis and premature labor.

Inflammatory cytokines seem to play a key role in mechanisms initiating labor. Since cytokine levels are higher in preterm than in term labor, it has been hypothesized that labor-inducing effects of cytokines are inhibited by an upregulated production of cytokine antagonists, such as soluble cytokine receptors, at early stages of gestation. In this study, TNF, IL-1, IL-6, IL-8 and soluble TNF receptors (sTNFRs) were measured in amniotic fluid samples from a) 39 women in premature labor, b) 25 women who where not in labor but delivered prematurely, and c) 33 women in term labor. Fifty-four of the placentas from premature deliveries were evaluated for presence of histological chorioamnionitis. Chorioamnionitis was associated with increased levels of TNF, IL-1 and IL-6, whereas elevated IL-1, IL-6 and IL-8 concentrations were found in premature parturition with no signs of infection. Concentrations of sTNFR were lower in preterm than in term deliveries. The present study confirms the participation of inflammatory cytokines in parturition. Multivariate analysis suggests a dominant, role of IL-1 in the presence of chorioamnionitis, whereas IL-6 seems to be more important during idiopathic premature labor. TNFR data do not support the hypothesis that production of cytokine antagonists is upregulated prematurely to prevent partirution.

Amniotic Fluid↗
PubMed1997

Prediagnostic level of fatty acids in serum phospholipids: omega-3 and omega-6 fatty acids and the risk of prostate cancer.

Ecological and case-control studies have demonstrated a positive correlation between consumption of fat and the risk of prostate cancer. Two recent human studies have focused on alpha-linolenic acid as a risk factor for prostate cancer. Animal experiments have shown that dietary omega-6 polyunsaturated fatty acids have generally stimulated tumour development, whereas omega-3 polyunsaturated fatty acids have diminished it. The aim of our study was to investigate the association between these fatty acids and the subsequent risk of prostate cancer. Blood donors to the Janus serum data bank in Norway, who later developed prostate cancer, were matched to blood donors without prostate cancer (141 matched sets); the proportional level of fatty acids measured before diagnosis in the donors' serum was examined. The risk of later prostate cancer was analysed by conditional logistic regression. Increasing risk for prostate cancer was found with increasing quartiles of palmitoleic, palmitic and alpha-linolenic acid. An inverse risk association was found with increasing levels of tetracosanoic acid, for the ratios of linoleic to alpha-linolenic acid and arachidonic to eicosapentaenoic acid. There was no clear association between the risk effect of total omega-3 and total omega-6 fatty acids. There were no indications of a relationship between fatty acids and more aggressive cancers. Our results verify recent findings of a positive association between alpha-linolenic acid and a negative association between the ratio of linoleic to alpha-linolenic acid and the risk of prostate cancer.

Case-Control Studies↗
PubMed1997

Prenatal growth in symmetric and asymmetric small-for-gestational-age infants.

We tested the hypothesis that growth retardation in symmetric small-for-gestational-age (SGA) infants may start in the first trimester of pregnancy, whereas in asymmetric SGA infants, it may start in the third trimester. We also examined if there may be a brain sparing effect in asymmetric SGA infants. Infants were classified as symmetric or asymmetric SGA infants, and 474 non-SGA infants. Intrauterine growth was assessed by prenatal ultrasonic measurements of fetal abdominal diameter, femur length and biparietal diameter at week 17, 25, 33 and 37 of gestation. Cross-sectional data as well as longitudinal growth curves suggested that growth retardation in both SGA groups started in the second trimester, and followed similar patterns until birth. Thus, our results did not support the hypothesis that symmetric and asymmetric growth retardation is associated with clear temporal differences in growth, and we found no sign of brain sparing in asymmetric compared to symmetric SGA infants.

Abdomen↗
PubMed1997

Dubowitz assessment of gestational age and agreement with prenatal methods.

We compared assessment of gestational age by Dubowitz score with ultrasonic measurement of the biparietal diameter (BPD), and then evaluated how infants were classified by these methods as small-for-gestational age (SGA), and as pre- or post-term births. BPD gestational age was assessed at week 17 to 20 of pregnancy while the Dubowitz scoring was done at birth. "Limits of agreement" between methods and kappa values were calculated and used to evaluate agreement. Among 839 included infants, there was moderate agreement between Dubowitz score and BPD (limits of agreement; -2.3; +2.1 weeks; weighted kappa: 0.46) in the assessment of gestational age. Agreement between Dubowitz score and BPD in the classification of SGA (kappa: 0.75, 95% confidence interval [CI]: 0.69-0.81) and preterm infants (kappa: 0.68, 95% CI: 0.56-0.80) was good, whereas agreement on infants born post-term was no better than chance (kappa: 0.14, 95% CI: -0.02(-)+0.30). We conclude that despite moderate agreement between Dubowitz score and BPD in the assessment of gestational age, agreement in the classification of low-birth-weight infants as SGA and as premature births was good.

Cephalometry↗
PubMed1996

Pre- and post-natal growth in children of women who smoked in pregnancy.

Pre- and post-natal growth was studied from week 17 of pregnancy until 5 years of age in children of women who reported daily smoking at the time of conception, and compared to the growth in children of non-smokers. Fetal abdominal diameter, femur length and biparietal diameter were measured in weeks 17 and 37 of pregnancy, and weight, height and head circumference were measured at birth, and at 6, 13 and 60 months of age in 185 children of smokers and 345 children of non-smokers. Cross sectional data at birth showed that infants of smokers had lower weight and length, but similar ponderal index as infants of non-smokers and this may suggest a symmetrical growth retardation. Longitudinal growth curves indicated that the growth retardation took place in the second half of pregnancy. During the first 5 years of life, children of smokers had complete catch-up growth in weight, a partial catch-up in height, and no catch-up growth in head circumference. At 5 years, children of smokers had a higher ponderal index and skinfold thickness, suggesting that these children, on average, were more obese than children of non-smokers.

Body Height↗
PubMed1996

Morbidity during the first year of life in small for gestational age infants.

Postneonatal morbidity during infancy was studied in 284 small for gestational age (SGA) and 359 non-SGA term infants. None of these babies had congenital malformations and they were born to para 1 and para 2 mothers. SGA infants had an increased risk (OR: 1.7, 95% confidence interval: 1.1-2.6) of being admitted to hospital compared with non-SGA infants. The principal cause was respiratory tract infections. Increased hospitalisation among SGA infants was a factor only if the mother was a smoker-that is, smoked cigarettes at the time of conception. Among subgroups of SGA babies, there was an increased risk for infants of non-repeaters (women without a previous SGA child) (OR: 2.4, 95% CI: 1.4-3.8) and for infants with symmetric (OR: 2.0, 95% CI: 1.2-3.3) body proportions compared with non-SGA infants. The results suggest that, beginning in early pregnancy, growth retardation may have long term consequences for subsequent infant morbidity, particularly if the mother is smoker.

Adult↗
PubMed1995

[To how much strain are families with asthmatic children exposed?].

Children with bronchial asthma may have coping problems which involve the whole family. The aim of this study was to find out what strain such families may experience. A questionnaire was sent to all children who, during a five year period, were registered as having a diagnosis of bronchial obstruction in the Department of Paediatrics, Innherred Hospital, Norway. The parents of a sample of the children were interviewed, and the parents of 42 children also answered a questionnaire about coping problems and strain. The results showed that the prevalence of coping problems and strain was low for these families at the time of the interview. Coping problems were greater during the first two years after asthma debut. Mothers felt more strain than the fathers during the two first years.

Adaptation, Psychological↗
PubMed1995

[What kind of information does the health services give to children with asthma and their parents?].

Good information to families who have children with bronchial asthma is essential for treatment and in helping the family to cope. The aim of this study was to find out what kind of information the parents meant they had received, their knowledge about asthma, and what sanitary measures had been taken at home. A questionnaire was sent to all children (N = 431) who, during a five year period, were entered into the records of the Department of Paediatrics, Innherred Hospital, Norway, with the diagnosis bronchial obstruction. A selected group of 55 children and their parents were also interviewed. The results showed that the parents were not satisfied with the information they had received about the illness and about effects and side effects of the medication. Furthermore, their knowledge about these matters was not satisfactory, judged both by themselves and by the interviewer. It was more difficult to quit smoking or to stop keeping animals than to do extra cleaning at home. Few parents were informed about their possibilities of receiving financial support and about patient organisations. Only in a few cases did the health service provide the school with information on the child's disease.

Adult↗
PubMed1994

Intercondylar notch width and the risk for anterior cruciate ligament rupture. A case-control study in 46 female handball players.

We measured the intercondylar notch of the femur in female handball players from radiographs of 20 players with previous unilateral anterior cruciate ligament injury, and 26 controls without injury. The groups were comparable regarding age, height, weight and level of performance. Intercondylar fossa radiographs were obtained in a posteroanterior axial position. The anterior opening of the intercondylar notch was narrower in the healthy knee of the injured group compared to the controls. There was an increased risk of anterior cruciate ligament injury associated with decreasing notch opening: female handball players with 17 mm or less anterior notch width were 6 times more susceptible to anterior cruciate ligament injury compared to players with wider notch width.

Adolescent↗