Early sexual maturation,central adiposity and subsequent overweight in late adolescence. A four-year follow-up of 1605 adolescent Norwegian boys and girls: the Young HUNT study

Background  

Early sexual maturation has been associated with overweight that may persist after the completion of biological growth and development. We have prospectively examined the influence of early sexual maturation on subsequent overweight in late adolescence and assessed if this association was modified by central adiposity in early adolescence.     

A comparison of cesarean section frequencies in two Norwegian hospitals

The two largest Norwegian obstetrical departments, in the cities of Bergen and Stavanger, differ markedly with regard to the frequency of Cesarean section. During the 1970's the proportions rose in both departments, but the Stavanger rate remained about half of that in Bergen, the latter following the national average. These differences were not reflected in the perinatal mortality, which had the same rates and fell equally in both hospitals. To search for explanations, all records of Cesarean section cases from the years 1974 and 1979 were studied in both hospitals. We found that mechanical indications, meaning disproportion and prolonged labor, accounted for most of the difference, whereas there was no significant rise in the frequencies for the indication fetal asphyxia in either of the hospitals, these being numerically the most important indications. In fact, there was no significant rise for mechanical indications in Stavanger between 1974 and 1979, whereas in Bergen the increased frequency for this indication gave the highest significance level for any of the seven subgroups of indications. It is suggested that the chain of command may be an important cause of the observed differences between the two departments, although this is not reflected in any stated or conscious policy in either place.     

Relationships between indoor environments and nasal inflammation in nursing personnel

In this study, the authors sought to address the relationships between measured indoor environmental factors and nasal patency (i.e., minimum cross-sectional area) and volume and markers of nasal inflammation in nasal lavage fluid. Clinical data were obtained for 115 females who worked at 36 geriatric nursing departments. The indoor climates in the nursing departments were characterized by high room temperatures (median = 23 degrees C), low relative air humidities (median = 24%), and high air exchange rates indicated by low carbon dioxide levels (median = 570 ppm). Evidence of microbial amplification was observed in the ventilation unit in 3 of the departments. Decreased nasal patency was observed relative to microbial amplification in the ventilation units (minimum cross-sectional area 1 = 0.80 cm2 vs. 0.64 cm2, p = .003, minimum cross-sectional area 2 = 0.80 cm2 vs. 0.67 cm2, p = .02) and in relation to elevated indoor temperature (volume 1 = 3.46 cm3 vs. 3.22 cm3, p = .03). The authors concluded that the indoor environment may have affected the nasal mucosa of nursing personnel, thus causing nasal mucosal swelling. The results support the view that fungal contamination of air-supply ducts may be a source of microbial pollution, which can affect the nasal mucosa.     

Impact of progestins on estradiol potentiation of the glutamate calcium response

One mechanism by which estrogen may modulate cognitive function is through potentiation of glutamate-mediated rises in intracellular calcium ([Ca2+]i) with resultant effects on neuronal morphology and signaling. Since progesterone is a component of hormone replacement therapy (HRT), we sought to determine whether therapeutically relevant progestins attenuated or blocked estrogen potentiation of glutamate-induced [Ca2+]i rises. 17beta-estradiol and progesterone, alone or in combination, significantly potentiated the rise in [Ca2+]i. When co-administered, progesterone attenuated the estrogen response to the level seen with progesterone alone. In contrast, medroxyprogesterone acetate (MPA) had no effect when administered alone and completely blocked the 17beta-estradiol-induced potentiation when co-administered. These results may have important implications for effective use of HRT to maintain cognitive function during menopause and aging.     

Development and validation of an enzyme-linked immunosorbent assay to measure vitellogenin in the zebrafish (Danio rerio)

In this study, an enzyme-linked immunosorbent assay (ELISA) was developed to quantify vitellogenin (Vtg) in zebrafish (Danio rerio). Zebrafish Vtg (zf-Vtg) was purified from whole-body homogenates of estradiol-exposed zebrafish, and polyclonal antibodies against zf-Vtg were raised. Using purified zf-Vtg as a standard and anti-zf-Vtg antibodies (DR-264), a competitive ELISA method was set up and validated. The working range of the assay is from 1 to 30 ng/ml (20-80% binding), and the detection limit is 0.4 ng/ml for purified zf-Vtg. In whole-body homogenates samples, the practical detection limit is higher than that for purified Vtg (40 ng/ml) due to matrix effect. The intra- and interassay variations were 4.7% and 14%, respectively, at 50% binding (n = 36). Its usefulness to detect changes in Vtg concentration in other cyprinid fish was also tested. In addition, the assay was used to assess Vtg induction in male zebrafish exposed to 17beta-estradiol (E2). Exposure of male zebrafish to 0.1, 1, 10, and 100 microg/L of E2 for 7 d led to a Vtg induction from the lowest concentration. The results show the suitability of the developed ELISA to quantify Vtg inductions in zebrafish, the cross-reactivity of DR264 antibodies with commonly used cyprinids, and the potential of zf-Vtg induction as a sensitive biochemical endpoint that could be used to detect estrogenic properties of chemical substances.     

Prevalence of, and risk factors for, HSV-2 antibodies in sexually transmitted disease patients, healthy pregnant females, blood donors and medical students in Tanzania and Norway

The prevalence of specific HSV-2 antibodies was studied in Tanzanian and Norwegian sexually transmitted disease (STD) patients (1095) and non-STD patients (488). Correlates to demographic and behavioural factors were evaluated. Seropositivity was determined by the non-commercial peptide-55 enzyme-linked immunoassay. The prevalence of HSV-2 antibodies was 70% in Tanzanian and 17% in Norwegian STD patients, 35% in Tanzanian blood donors and pregnant women, and 4, 7 and 14% in Norwegian medical students, blood donors and pregnant women respectively. A higher HSV-2 prevalence was associated with female sex, increasing age, previous STDs, history of genital HSV infection, coitarchal age (age at first intercourse) <15 years and HIV seropositivity. Compared to previous data, the prevalence of HSV-2 antibodies in Tanzanian STD patients has increased remarkably. In Norwegian STD patients our results are consistent with, or lower than, the prevalence previously reported in Western Europe. Demographic rather than behavioural factors were associated with higher prevalence of HSV-2 antibodies in STD patients.     

Evaluation of low back pain and assessment of lumbar corsets with and without back supports.

A method is described for evaluating the progress of patients with back pain. Various symptoms were scored on analogue scales and spinal motion was measured by various techniques. These data were integrated to make subjective and objective indices respectively. Reasonable reproducibility of the measurements was obtained. This technique was used to elucidate the role of the lumbar support in surgical corsets in relief of back pain. Sufferers from back pain were randomly allocated to corsets with and without lumbar supports. There was significant improvement in those with a support compared with those without. On the other hand objective changes measured with the corset removed did not differ between the 2 groups. This study indicates that the spinal support in a lumbosacral corset makes a significant contribution towards the relief of symptoms.     

Single dose pharmacokinetics of tiaprofenic acid. Effects of food and severe renal insufficiency

The single oral dose pharmacokinetics of tiaprofenic acid (Surgam) has been investigated in fasting and non-fasting healthy volunteers (200 and 300 mg) and in fasting patients with severe renal insufficiency (200 mg). A dose independent pharmacokinetics of tiaprofenic acid was shown in fasting healthy volunteers and the following parameters were calculated after administration of 200 mg: tl = 0.53 +/- 0.15 h, tm = 1.28 +/- 0.19 h, cm = 27.1 micrograms/ml, ka = 2.79 +/- 0.93 h-1, lambda 2 = 1.06 +/- 0.14 h-1, t1/2 = 3.0 +/- 0.2 h, AUCl-infinity = 80 +/- 7 mg X h/l, Clt = 43.8 +/- 3.7 ml/min and V beta = 11.1 +/- 0.8 l. A small, but significant positive deviation from linearity was observed with increasing dose for cm and AUCl-infinity in non-fasting healthy volunteers, probably due to a slightly higher bioavailability of the 300 mg formulation in the non-fasting state as compared with the 200 mg formulation. Intake of food decreased cm significantly at both dosage levels from 27.1 to 19.1 micrograms/ml and from 47.9 to 39.1 micrograms/ml for 200 and 300 mg, respectively. The absorption kinetics of tiaprofenic acid was not significantly different in fasting healthy volunteers and in fasting patients with severe renal insufficiency. However, a significant increase in t1/2 and AUCl-infinity to 5.8 +/- 0.9 h and 173 +/- 34 mg X h/l, respectively, and a significant decrease in total body clearance to 25.5 +/- 5.3 ml/min were observed in this category of patients. No correlation was found between creatinine clearance and tiaprofenic acid clearance.     

The association between smoking and the prevalence of intermittent claudication

The objective of this study was to investigate the association between smoking and the prevalence of intermittent claudication (IC). Between 1995 and 1997, all residents aged 20 years or older in Nord-Tr?ndelag County, Norway, were invited to take part in the Nord-Tr?ndelag Health Study (Helseunders?kelsen i Nord-Tr?ndelag: HUNT 2). A total of 19748 participants aged 40-69 years attended. Responses to 12 questions on IC (including a Norwegian translation of the Edinburgh Claudication Questionnaire) had been previously tested against the ankle-brachial pressure index (ABPI < 0.9), and an algorithm of the best test properties was used to identify people with IC. Using logistic regression analysis we computed age-adjusted prevalence odds ratios (OR) for the association between smoking and IC. Both current (ORmen = 3.8, confidence interval (CI) 2.1-6.7, ORwomen = 2.2, CI 1.4-3.4) and former smokers (ORmen = 1.7, CI 0.9-3.2, ORwomen = 1.7, CI 1.1-2.7) had a higher prevalence of IC compared with those who had never smoked, and individuals who had stopped smoking more than 20 years previously had a substantially lower prevalence of IC (ORmen = 0.2, CI 0.1-0.5, ORwomen = 0.4, CI 0.2-0.8) than current smokers. We found no association between passive smoking and IC in either men or women. Current and previous smoking habits were positively associated with the prevalence of IC, and smoking cessation was negatively associated in men and women. Passive smoking was not associated with IC in this study.     

Characterization of the tetanus toxin model of refractory focal neocortical epilepsy in the rat

PURPOSE: To characterize in detail a model of focal neocortical epilepsy. METHODS: Chronic focal epilepsy was induced by injecting 25-50 ng of tetanus toxin or vehicle alone (controls) into the motor neocortex of rats. EEG activity was recorded from electrodes implanted at the injection site, along with facial muscle electromyographic (EMG) activity and behavioral monitoring intermittently for up to 5 months in some animals. Drug responsiveness was assessed by using the antiepileptic drugs (AEDs) diazepam (DZP) and phenytoin (PHT) delivered systemically, while 1,2,3,4-tetrahydro-6-nitro-2,3-dioxo-benzo[f]quinoxaline-7-sulfonamide (NBQX), a competitive antagonist at AMPA receptors, was administered directly to the brain to investigate the potential benefits of focal drug delivery. RESULTS: Tetanus toxin induced mild behavioral seizures that persisted indefinitely in all animals. EEG spiking activity, occurring up to 80% of the time, correlated with clinical seizures consisting of interrupted behavioral activity, rhythmic bilateral facial twitching, and periods of abrupt motor arrest. Seizures were refractory to systemic administration of DZP and PHT. However, focal delivery of NBQX to the seizure site reversibly reduced EEG and behavioral seizure activity without detectable side effects. CONCLUSIONS: This study provides a long-term detailed characterisation of the tetanus toxin model. Spontaneous, almost continuous, well-tolerated seizures occur and persist, resembling those seen in neocortical epilepsy, including cortical myoclonus and epilepsia partialis continua. The seizures appear to be similarly resistant to conventional AEDs. The consistency, frequency, and clinical similarity of the seizures to refractory epilepsy in humans make this an ideal model for investigation of both mechanisms of seizure activity and new therapeutic approaches.