PubMed Health⌕ Search

Biomedical subjects

L B Andersen

Publications and source records attributed to L B Andersen.

At least 19 recordsLinked to original sources
PubMed1996

[Changes in physical activity are not reflected in physical fitness of older teenagers. A 2-year follow-up study].

The study describes changes over two years in different physical fitness measures and the relationship between these changes and changes in physical activity. Maximal aerobic work capacity (watt(max)), functional strength, muscle endurance, agility and flexibility were measured in 259 randomly selected high school boys and girls 16.5 years of age and followed-up two years later, while they still attended school. Most physical fitness measures increased over time in boys, and in girls an increase was found in arm extensor strength and trunk extensor endurance, but watt(max) per kg body mass decreased. Changes in physical performance between 16 and 18 years of age seem to be very similar in different countries, despite differences in physical activity patterns and absolute level of performance. No change was found in time spent participating in physical activity or sports activity in either gender, but fewer girls participated in leisure-time sports at the second test (p < 0.001). Change in physical activity or sports activity did not relate to change in physical fitness level. The relationships between level of sports participation (competition, for health or none) and physical fitness measures at baseline and at the second test were weak or non-significant. Three explanations for the weak relationship between physical activity and fitness are suggested: a) part of the variability in fitness is explained by genetics, b) growth and hormonal changes, especially in boys, override the stimulus of training, and c) the physical fitness level in adolescents is so high that only physical activity at high relative intensity is supposed to have an effect on the fitness level.

Adolescent↗
PubMed1996

Lineage-specific CaN19 expression in human skin: lack of expression in normal melanocytes.

Although expression of CaN19 is reduced in cell lines derived from tumors of diverse origin, its expression in their normal counterparts has not been studied in detail. We find that CaN19 mRNA is expressed at very low to undetectable levels in normal melanocytes as well as malignant melanoma cell lines, confirming that CaN19 expression in normal cells is lineage-dependent.

Cells, Cultured↗
PubMed1996

Tracking of risk factors for coronary heart disease from adolescence to young adulthood with special emphasis on physical activity and fitness. A longitudinal study.

Physical activity (PA), fitness and selected coronary heart disease (CHD) risk factors were studied in 2 Danish adolescent cohorts; changes in PA and fitness from the age of 16-18 years were measured in a subgroup of high school children; changes in lifestyle, fitness level and coronary heart disease risk factors were measured from late adolescence to young adult hood in a random sample of subjects attending school at baseline. Risk factors and physical fitness tracked from adolescence to young adulthood. The proportion of subjects in the upper quintile of risk still being in the upper quintile 8 years later was 2-3 times the expected in most risk factors. No relationship was found between physical activity and coronary heart disease risk factors in the adolescent population, and only a weak, but highly significant, relationship was found between VO2max and blood pressure in the large cohort of 17 year olds. These weak relationships could result from a relatively high fitness level and a small variation in fitness level in the young Danish population. Because of a great statistical power in the group of subjects at the same age from population 2, it was possible to analyze the relationship between blood pressure and fitness further. Lower blood pressure was found with higher fitness level, but only VO2max, and not physical activity, related to blood pressure, and the relationship became weaker with higher fitness level. In the adult male population, the variations in both VO2max and risk factors were much larger and a great number of the men had become sedentary. Inactive lifestyle was associated with low educational level, and the decrease in fitness and increase in coronary heart disease risk factor levels were more distinct in the former trade and vocational students than in the 'gymnasium' students. In the 17-year-old cohort, lower blood pressure was found with higher VO2max until a level of 53 and 45 ml.min-1.kg-1 in boys and girls, respectively, but above these levels no relationship was found between VO2max and blood pressure.

Adolescent↗
PubMed1995

A maximal cycle exercise protocol to predict maximal oxygen uptake.

Maximal oxygen uptake (VO2max) was predicted from maximal power output (MPO) in a progressive cycle ergometer test. The subjects were 232 men and 303 women 15-28 years of age. The relationship between VO2max and MPO was: VO2max (1.min-1) = 0.16 + (0.0117 x MPO) (w). A correlation coefficient of r = 0.88 was found between MPO and VO2max. Test-retest reliability was evaluated by two procedures. Standard deviations of test-retest differences in MPO and VO2max using the same standardized procedure in 35 subjects, were 10% and 8%, respectively, and Pearson correlations between test and retest values were 0.95 and 0.96, respectively. When MPO of tests conducted at the schools was compared to a standardized test performed by a physiologist in 267 subjects, test-retest Pearson correlation was 0.82. A prediction model only including MPO and explaining 80% of the variability in VO2max, is suggested for use in healthy adolescents and young adults.

Adolescent↗
PubMed1995

Physical activity and physical fitness as protection against premature disease or death.

It is known from prospective studies that the incidence of coronary heart disease (CHD) is lower in the physically active compared with the sedentary part of the population, and the rate of CHD is lower with higher fitness level. In studies where both physical activity (PA) and fitness are assessed, only fitness, and not PA, appear to be an independent predictor of mortality from CHD. It is unclear whether other fitness components than maximal oxygen uptake (Vo2max) have a beneficial effect on the rate of CHD. Further, it seems likely that there is an upper threshold of fitness (Vo2max) above which no further improvement in risk factors for CHD is found. However, most middle-aged people have fitness levels below this threshold. There is no doubt that the middle-aged sedentary person benefits from physical activity regardless of type and intensity, and it may be easier to motivate a sedentary person to carry out moderate physical activity. However, it is likely that the best effect is achieved by performing physical activity of a type and intensity sufficient to improve the fitness level. Still, recommendations of type, frequency, duration and intensity are matters of debate.

Coronary Disease↗
PubMed1995

Coronary heart disease risk factors, physical activity, and fitness in young Danes.

In a random sample of young Danish adults (86 men and 115 women, 23-27 yr of age) maximal oxygen uptake (VO2max), physical activity (PA), blood pressure, blood lipids, body fat content, and smoking habits were studied. Cholesterol, triglyceride and body fat related negatively to VO2max. The ratio HDL/total cholesterol was positively related to VO2max (r = 0.3, P < 0.001), but no relationship was observed for HDL cholesterol. No association was found between PA and any of the risk factors. The relationships between different measures of PA and directly measured VO2max was around r = 0.3. No relationship existed between heart rate recorded during submaximal testing and PA (r = 0.0), which indicates that the method of assessing VO2max is important in demonstrating relationships to PA and risk factors. In conclusion, a favorable coronary heart disease risk profile was related to a higher VO2max, but not to time spent on physical activity. This suggests that in this age group intensity must be high enough to have an effect on VO2max before a preventive effect is present.

Adult↗
PubMed1994

[Viral encephalitis after tick bite].

TBE is caused by a Flavivirus and is endemic in certain areas of Central and Eastern Europe, such as Austria, the south of Germany, Hungary, Czechoslovakia, Poland, the former Yugoslavia and SNG and certain areas of Sweden and Finland. Recent developments in the Eastern European countries have made them popular with Danish travellers, who are thus exposed to infection. Until now TBE has been a very rare disease in Denmark. The clinical course is biphasic being preceded by an incubation period of ten days. After the initial phase with uncharacteristic symptoms, a period af about five days follows where the patient has no symptoms. About one-third of the patients develop meningo-encephalitis where paresis can be seen. The course of the disease is often prolonged. The prognosis is good in terms of full recovery and low mortality. The diagnosis is made serologically with haemagglutination-inhibition test or ELISA-technique. Differential diagnosis includes other causes of viral encephalitis and Lyme disease with neurological manifestations, when there is a history of tick-bites. Vaccination provides good protection and is recommended for certain travellers with trips of some duration in endemic areas.

Denmark↗
PubMed1994

[HIV-positive drug addicts treated at the Copenhagen City Drug Dependency Clinic 1986-1992].

The Copenhagen City Drug Dependency Clinic at the former Rudolph Bergh's Hospital was established in 1986 as part of the measures taken by the municipality of Copenhagen to control the spread of HIV/AIDS among the intravenous drug addicts in the City of Copenhagen. The aim was to attract those HIV-positive drug addicts who were in no formal treatment for their drug addiction at other treatment centres and to retain them in treatment for a longer period acknowledging the fact that no causal cure exists for either the drug addiction or for AIDS. The goal of the treatment was to reduce HIV-risk behaviour i.e. sharing needles and syringes and unprotected sex with multiple partners and to reduce the adverse medical and social consequences of continued drug abuse. The treatment was supported by methadone treatment. During the five year period of 1986-92 a total of 196 HIV-positive drug addicts were referred to the clinic. A little more than half of those referred for the first through the third time and five out of six referred for the fourth time were admitted to treatment at the clinic. Half of the 126 first-time treated patients were retained in treatment for up to one year, while the rest were retained in treatment from one to five years. The mean time spent in treatment at the clinic was shorter for the relatively few patients who were admitted for the second time than for those admitted for the first time. At the end of the study 39 patients (20%) had died, most of them for non-AIDS related reasons.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Dietary factors related to fitness in young men and women.

BACKGROUND: In a previous paper we reported an inverse relationship between fitness and serum lipids in this group of young subjects. The present study investigates whether a higher fitness level was associated with a more prudent diet and whether this contributed to the observed relationship between fitness and serum lipids. METHODS: The study sample, comprising 70 women and 49 men ages 23-27 years, was a subgroup of a large random sample. Aerobic fitness was measured directly as maximal oxygen uptake (ml O2 min-1 kg-1) and dietary intake as 7-day food records. RESULTS: The highest fitness tertile had an intake of dietary fiber higher than that of the lowest tertile (25.2 g/10 MJ vs 21.9 g/10 MJ, P < 0.05) and a lower intake of sucrose (7.2 E% vs 9.8 E%, P < 0.01), whereas total fat intake and the ratio between polyunsaturated and saturated fatty acids were similar (35.4 E% vs 36.5 E%, P > 0.05, 0.39 vs 0.34, P > 0.05, respectively). No differences were observed in intake of alcohol, protein, and total carbohydrate. Multiple regression analyses showed no impact of dietary variables upon the relationship between serum lipids and fitness. CONCLUSIONS: Better fitness was associated with a better dietary composition with respect to dietary fiber and sucrose, but not to fat. The observed inverse relationship between fitness and serum lipids was not related to diet.

Adult↗
PubMed1994

Blood pressure, physical fitness and physical activity in 17-year-old Danish adolescents.

OBJECTIVE: To test the relationship between physical activity and physical fitness, and the relationship between these variables and the primordial risk factor blood pressure (BP). DESIGN: A cross-sectional study of all Danish pupils in the same grade at 'gymnasium' (the Danish upper secondary school). SETTING: Tests and questionnaires were administered by physical education and biology teachers according to a prescribed scheme. SUBJECTS: Study subjects were 13810 adolescents with a mean age of 17.1 years. Physical activity, smoking habits, and physical performance were measured in 4862 boys and 6573 girls. Blood pressure was measured in 2474 boys and 3535 girls. No difference was found in BP, physical activity and fitness variables between this group and a representative group of Danish school children at the same age. MAIN OUTCOME: Blood pressure and health-related physical performance such as strength, muscle endurance, flexibility and maximal oxygen uptake (VO2max) estimated from heart rate at submaximal workload were measured. Sports activity, other physical activity and smoking habits were assessed by questionnaires. RESULTS: There was a negative relationship between BP and VO2max up to the 50% percentile (50 ml min-1 kg-1) in boys and up to the upper 80-90% percentile (45 ml min-1 kg-1) in girls. In a multiple regression model with BP as dependent variable, VO2max related highly significant, also after adjustment for body weight and physical activity (P < 0.001). Other performance variables only explained a small part of the variance in BP. No relationship was found between BP and total physical activity or sports activity. CONCLUSION: In the adolescent population VO2max related negatively to BP after adjustment for body weight, physical activity, other fitness measures and sex, but physical activity or other fitness measures did not relate. Lower blood pressure was found with higher VO2max until levels of 50 and 45 ml min-1 kg-1 in boys and girls, respectively.

Adolescent↗
PubMed1994

Changes in physical activity are reflected in changes in fitness during late adolescence. A 2-year follow-up study.

The study describe changes over 2 years in different physical fitness measures and the relationship between these changes and changes in physical activity. Maximal aerobic work capacity (Wattmax), functional strength, muscle endurance, agility and flexibility were measured in 259 randomly selected high school boys and girls 16.5 years of age and followed-up 2 years later, while they still attended school. Most physical fitness measures increased over time in boys, and in girls an increase was found in arm extensor strength and trunk extensor endurance, but Wattmax per kg body mass decreased. Changes in physical performance between 16 and 18 years of age seem to be very similar in different countries, despite differences in physical activity patterns and absolute level of performance. No change was found in time of participation in physical activity or sports activity in either gender, but fewer girls participated in leisure-time sports at the 2nd test (p < 0.001). Change in physical activity or sports activity did not relate to change in physical fitness level. The relationships between level of sports participation (competition, for health or none) and physical fitness measures at baseline and at the 2nd test were weak or non-significant. Three explanations for the weak relationship between physical activity and fitness are suggested: (A) part of the variability in fitness is explained by genetics, (B) growth and hormonal changes, especially in boys, override the stimulus of training, and (C) the physical fitness level in adolescents is so high that only physical activity at high relative intensity is supposed to have an effect on the fitness level.

Adolescent↗
PubMed1994

Changes in CHD risk factors with age: a comparison of Danish adolescents and adults.

In 1983 a representative sample of Danish adolescents 16-19 yr of age were selected to participate in a study to determine risk profile for coronary heart disease. Eight years later (1991), we performed a follow-up study of the same participants 23-27 yr of age to compare risk factors. In the young adults power was generally high, 48.0 (SD +/- 7.8) and 39.6 (SD +/- 6.5) ml.min-1.kg-1 for men and women, respectively. Only 30% of the men and 26% of the women did not regularly participate in sport activities. Seventy-five percent of both genders bicycled daily, 50% of the men and 42% of the women as their daily transportation year round. Twenty percent, more men than women, were considered to be inactive. Women had a higher ratio of HDL-C/C than men (0.32 for women vs 0.26 for men). Mean values for blood pressure were 134/83 mm Hg and 122/78 mm Hg for men and women, respectively. Thirty-eight percent of the men and 10% of the women had an elevation above 140/90 mm Hg in either systolic blood pressure (SBP) or diastolic blood pressure (DBP). Cholesterol levels were high (10%) when compared with the U.S. population, but triglyceride levels were substantially lower (40%). Comparing the 1991 adults with the 1983 adolescents, the ranges were wider. In conclusion, the risk factor profile changes in men were less favorable than the profile for women; the changes in high risk groups were larger than changes in mean values.

Adolescent↗
PubMed1993

Maximal oxygen uptake, maximal voluntary isometric contraction and physical activity in young Danish adults.

In a randomly selected sample of 88 men and 115 women, aged 23-27 years from Denmark, maximal oxygen uptake (VO2max), maximal voluntary isometric contraction (MVC) in four muscle groups and physical activity were studied. The VO2max was 48.0 ml.min-1.kg-1 and 39.6 ml.min-1.kg-1 for the men and the women, respectively. The MVC was 10% lower than in a comparable group of Danes of the same age and height studied 35 years ago. Only in men was sports activity directly related to VO2max (ml.min-1.kg-1; r = 0.31, P < 0.01). The MVC of the knee extensors was related to VO2max in the men (r = 0.31, P < 0.01), but there was no relationship between the other measurements of MVC and VO2max. In the women VO2max (ml.min-1.kg-1) was only related to body size, i.e. body mass index, percentage body fat and body mass [(r = -0.47, -0.48 (both P < 0.001) and -0.34 (P < 0.01), respectively)]. There were differences in VO2max in the men, according to education and occupation. Blue collar workers and subjects attending vocational or trade schools in 1983 had lower VO2max, and more of them were physically inactive. In the women differences were also found, but there was no clear pattern among the groups. More of the women participated regularly in sports activity, but more of the men were very active compared to the women.

Adult↗
PubMed1993

An EcoRI RFLP in the 5' region of the human NF1 gene.

Von Recklinghausen neurofibromatosis or type 1 neurofibromatosis (NF1), is one of the most common autosomal dominant disorders. NF1 is characterized by neurofibromas, café-au-lait spots and Lisch nodules of the iris. The NF1 gene is located in 17q11.2. The restriction fragment length polymorphism reported here will be useful in linkage analysis in NF1 families.

Alleles↗
PubMed1993

Mutations in the neurofibromatosis 1 gene in sporadic malignant melanoma cell lines.

Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder characterized by progressive and variable involvement of tissues predominantly derived from the neural crest and a predisposition toward malignancies. The NF1 gene encodes neurofibromin, a GTPase-activating protein containing a GAP-related domain (NF1-GRD) that is capable of down-regulating ras by stimulating its intrinsic GTPase activity. We report a homozygous deletion of most of NF1 in one of eight malignant melanoma cell lines leading to loss of detectable mRNA and protein, as well as the apparent absence of protein and mRNA in another melanoma. This data suggests that NF1 can function as a tumour suppressor gene in the development or progression of malignant melanoma.

Chromosome Mapping↗
PubMed1993

An alternatively-spliced mRNA in the carboxy terminus of the neurofibromatosis type 1 (NF1) gene is expressed in muscle.

The gene for neurofibromatosis type 1 (NF1) was identified by positional cloning and found to contain two alternatively spliced exons. The first described alternatively spliced exon (exon 23a) is located within the GAP-related domain of the gene and inserts an additional 63 nucleotides into the NF1 mRNA. The second alternatively spliced exon (exon 48a) is located near the extreme carboxy terminus of the gene and inserts an additional 54 nucleotides into the mRNA. This second isoform, termed 3'ALT, was originally detected while screening a fetal brain cDNA library. Examination of its expression by reverse-transcribed RNA PCR demonstrates high level of expression in cardiac muscle, skeletal muscle and smooth muscle. Trace levels of expression are detected in brain and nerve. The 3'ALT isoform is expressed in fetal cardiac muscle, adult left ventricle and cardiac Purkinje cells. Further confirmation of the existence of this isoform was obtained by blotting the PCR products with a radiolabeled oligonucleotide entirely derived from sequences contained within exon 48a and by direct sequencing of the PCR products. Additionally, this isoform is expressed in muscle tissues from other vertebrate species. The expression of this isoform in muscle suggests that the NF1 gene may play additional tissue-specific roles in muscle development and signal transduction.

Alternative Splicing↗