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T Scheike

Publications and source records attributed to T Scheike.

26 records · Page 2Linked to original sources
PubMed1997

Free insulin-like growth factor I serum levels in 1430 healthy children and adults, and its diagnostic value in patients suspected of growth hormone deficiency.

Serum levels of total insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) reflect endogenous GH secretion in healthy children, which makes them good diagnostic markers for screening of GH deficiency (GHD) in short children, although some controversy still exists. Only a minor fraction of the total IGF-I circulates in its free form, which is believed to be the biologically active form. However, our knowledge of the clinical or physiological value of determination of free IGF-I in serum is limited at present. In adults, the diagnostic value of total IGF-I and IGFBP-3 determinations in patients suspected of GHD has only been reported in a few studies, whereas no previous reports on the diagnostic value of free IGF-I levels in adults suspected of GHD exist. Serum levels of free IGF-I were determined in 1430 healthy children, adolescents, and adults by a newly developed, commercially available immunoradiometric assay (Diagnostic Systems Laboratories) to establish valid normative data for this analysis. We studied the diagnostic value of free IGF-I in relation to total IGF-I and IGFBP-3 determinations in adults who were suspected of GHD. A GH provocative test, using oral clonidine, was performed in 108 adult patients who had previously been treated with GH in childhood. In healthy subjects, free IGF-I levels increased during childhood, with the highest mean values during puberty. After puberty, a subsequent decline in serum levels of free IGF-I was apparent. We found, unmeasurable free IGF-I values in 34 of the prepubertal children (3.3%). All individuals over 8 yr of age had measurable free IGF-I levels that amounted to approximately 1% of the total IGF-I concentrations. Free IGF-I levels were below--2 SD in 56 of 79 GHD patients (sensitivity, 71%) and above--2 SD in 24 of 29 patients with a normal GH response (specificity, 83%). Multiple linear regression analysis demonstrated that free IGF-I was significantly dependent on peak GH levels, duration of the disease, and number of other pituitary axes affected. We conclude that free IGF-I serum levels increase during childhood with a peak in puberty, whereafter free IGF-I levels return to prepubertal levels. Three percent of healthy prepubertal children had unmeasurable free IGF-I levels using this assay. We found that determination of the free IGF-I serum concentration may predict the outcome of a GH provocative test in adults suspected of GHD, but that a single determination of free IGF-I offered no significant advantage compared to determination of total IGF-I or IGFBP-3 serum levels.

Adolescent↗
PubMed1996

The influence of climate on development of winter depression.

126 patients suffering from winter depression participated in the study. Every second week patients completed the 13 item Beck Depression Inventory (BDI) in the period September to May in the years 1991 to 1994. Local weather data from this period were obtained from the Meteorological Institute, Copenhagen. No significant correlation was found between score on BDI and cloud cover, rainfall or atmospheric pressure. A significant correlation was found between score on BDI and minutes of sunshine, global radiation, length of daylight and temperature. This is in accordance with the theory, that lack of light is a contributing factor for development of winter depression.

Adult↗
PubMed1996

Male reproductive health and environmental xenoestrogens.

Male reproductive health has deteriorated in many countries during the last few decades. In the 1990s, declining semen quality has been reported from Belgium, Denmark, France, and Great Britain. The incidence of testicular cancer has increased during the same time incidences of hypospadias and cryptorchidism also appear to be increasing. Similar reproductive problems occur in many wildlife species. There are marked geographic differences in the prevalence of male reproductive disorders. While the reasons for these differences are currently unknown, both clinical and laboratory research suggest that the adverse changes may be inter-related and have a common origin in fetal life or childhood. Exposure of the male fetus to supranormal levels of estrogens, such as diethlylstilbestrol, can result in the above-mentioned reproductive defects. The growing number of reports demonstrating that common environmental contaminants and natural factors possess estrogenic activity presents the working hypothesis that the adverse trends in male reproductive health may be, at least in part, associated with exposure to estrogenic or other hormonally active (e.g., antiandrogenic) environmental chemicals during fetal and childhood development. An extensive research program is needed to understand the extent of the problem, its underlying etiology, and the development of a strategy for prevention and intervention.

Animals↗
PubMed1995

[Body proportions of Danish children. Curves for sitting height ratio, subischial length and arm span].

No previous Danish growth charts have been published for sitting height, subischial leg length, armspan or the ratio of sitting height to stature. These growth charts are useful in the evaluation of dysproportional growth retardation. Foreign standards have previously been used. However, due to population-specific differences and "the secular trend", the construction of Danish growth charts was found to be appropriate. We examined 1977 children (927 boys and 1050 girls) from the Copenhagen area, aged six to 20 years. Height, sitting height and armspan were measured. Growth charts were constructed using local linear regression and smoothing of residuals. We found sitting height values in Danish children to be comparable to English and Norwegian children. Sitting height values were lower than values of Dutch children, but higher than values of Swiss and Swedish children. The extremities of Danish children were 3-4 cm longer than the extremities of English children, but Dutch children had 2-3 cm longer armspan than the Danish boys and girls. Growth charts for sitting height, sitting height ratio, subischial leg length and armspan are presented. These charts should be useful when evaluating dysproportionality in growth retarded children and when assessing the effect of growth modulating therapy in children.

Adolescent↗
PubMed1995

Serum insulin-like growth factor I (IGF-I) and IGF-binding protein 3 levels are increased in central precocious puberty: effects of two different treatment regimens with gonadotropin-releasing hormone agonists, without or in combination with an antiandrogen (cyproterone acetate).

Central precocious puberty (CPP) is characterized by early activation of the pituitary-gonadal axis, which leads to increased growth velocity and development of secondary sexual characteristics. It is generally believed that gonadal sex steroids stimulate pulsatile GH secretion, which, in turn, stimulates insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3) production. However, little is known about GH, IGF-I, and IGFBP-3 serum levels in children with precocious puberty. Treatment of CPP by GnRH agonists has become the treatment of choice. However, the effect of long term treatment with GnRH in combination with an antiandrogen (cyproterone acetate) to block the possible effect of adrenal androgens has not previously been evaluated. We, therefore, studied 40 patients with idiopathic CPP that were treated for 24 months with either GnRH analog (Buserelin) in combination with cyproterone acetate (Androcur; n = 23) or with long acting GnRH analog (Decapeptyl Depot; n = 17). We found that serum IGF-I levels were increased before treatment in both groups (mean +/- SE, 446 +/- 35 and 391 +/- 35 micrograms/L; P < 0.0001, respectively) compared to those in normal age-matched prepubertal children. Similarly, IGFBP-3 levels were significantly elevated (4675 +/- 209 and 4305 +/- 162 micrograms/L, respectively; P < 0.0001) in the two groups. Treatment with GnRH analog in combination with cyproterone acetate significantly decreased height velocity and serum IGF-I and IGFBP-3 levels to normal levels after 2 yr of treatment (P < 0.0001). Serum IGF-I levels remained unchanged during monthly im treatment with long acting GnRH analog, whereas IGFBP-3 levels significantly increased during the first year of this treatment despite unmeasurable estradiol levels. Thus, in both groups, the molar ratio between IGF-I and IGFBP-3 (i.e. free biologically active IGF-I) declined concomitantly with a decrease in growth velocity. Serum levels of IGF-I and IGFBP-3 (expressed as the SD score for bone age), but not those of estradiol, correlated with height velocity before and during treatment (r = 0.34; P < 0.0001 and r = 0.24; P = 0.003, respectively). Six of the patients with a subnormal GH response to clonidine had similar IGF-I and IGFBP-3 serum levels and growth velocity compared to the other 34 girls with CPP and a normal GH response.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMedDate not supplied

The epidemiology of febrile malaria episodes in an area of unstable and seasonal transmission.

This study investigated the epidemiology of uncomplicated falciparum malaria in an area of unstable and seasonal transmission in eastern Sudan. About 90% of malaria morbidity in this region occurs in the months of September to November, and very few malaria cases occur during the intensely arid Sudanese dry season and during years of drought. The malaria situation in the study site, the village of Daraweesh, was analysed during 3 consecutive malaria seasons in 1993-95 during which the 457 inhabitants suffered at total of 436 episodes of falciparum malaria. Using an Andersen-Gill proportional hazard model for recurrent events stratified by family, we have calculated the relative hazard for clinical malaria episodes by age, sex, haemoglobin genotype, blood type and infection in the previous season. The malaria risk was significantly lower in individuals aged 20-88 years than in the 5-19 years age-group. The relative protection due to adulthood varied between seasons (relative risk, RR, 0x34 to 0x67). Serological data were not consistent with the hypothesis that the age difference in incidence was due to differences in exposure. During the 1993 season the malaria incidence in males was lower than in females (RR = 0x75), during the 1994 season the incidences were comparable, whereas males had an increased risk of malaria in 1995 (RR = 1x87). The relative risk in individuals carrying the haemoglobin AS genotype compared to homozygous AA individuals was 0x57.

Adolescent↗
PubMedDate not supplied

Caffeine intake and fecundability: a follow-up study among 430 Danish couples planning their first pregnancy.

Fecundability has been defined as the ability to achieve a recognized pregnancy. Several studies on caffeine and fecundability have been conducted but have been inconclusive. This may be explained partly by lack of stratification by smoking. Furthermore, few researchers have tried to separate the effect of caffeine from different sources (coffee, tea, cola, and chocolate). Clearly, the relationship between caffeine and fecundability needs further research, given the high prevalence of caffeine intake among women of childbearing age. We examined the independent and combined effects of smoking and caffeine intake from different sources on the probability of conception. From 1992 to 1995, a total of 430 couples were recruited after a nationwide mailing of a personal letter to 52,255 trade union members who were 20 to 35 years old, lived with a partner, and had no previous reproductive experience. At enrollment and in six cycles of follow-up, both partners filled out a questionnaire on different factors including smoking habits and their intake of coffee, tea, chocolate, cola beverages, and chocolate bars. In all, 1596 cycles and 423 couples were included in the analyses. The cycle-specific association between caffeine intake and fecundability was analyzed in a logistic regression model with the outcome at each cycle (pregnant or not pregnant) in a Cox discrete model calculating the fecundability odds-ratio (FR). Compared to nonsmoking women with caffeine intake less than 300 mg/d, nonsmoking women who consumed 300 to 700 mg/d caffeine had a FR of 0.88 [95% confidence interval (CI) 0.60-1.31], whereas women with a higher caffeine intake had a FR = 0.63 (95% CI 0.25-1.60) after adjusting for female body mass index and alcohol intake, diseases of the female reproductive organs, semen quality, and duration of menstrual cycle. No dose-response relationship was found among smokers. Among males, the same decline in point estimates of the FR was present. Smoking women whose only source of caffeine was coffee (>300 mg/d) had a reduced fecundability odds-ratio (FR = 0.34; 95% CI 0.12-0.98). An interaction between caffeine and smoking is biologically plausible, and the lack of effect among smokers may be due to faster metabolism of caffeine. Our findings suggest that especially nonsmoking women who wish to achieve a pregnancy might benefit from a reduced caffeine intake.

Adult↗