Serum hormone concentrations during prolonged training in elite endurance-trained and strength-trained athletes

A study of 1 year was performed on nine elite endurance-trained athletes (swimmers) and on eight elite strength-trained athletes (weightlifters) in order to examine the effects of training on the endocrine responses and on physical performance capacity. The measurements for the determination of serum hormone concentrations were performed at about 4-month intervals during the course of the year. The primary findings demonstrated that during the first and most intensive training period of the year in preparing for the primary competitions similar but statistically insignificant changes were observed in the concentrations of serum testosterone, free testosterone and cortisol in both the endurance-trained and strength-trained groups. After that period the changes in hormonal response over the year were infrequent and minor. A significant (p less than 0.01) decrease occurred in the strength-trained group in serum-free testosterone during the second period, which was characterized by the highest overall amount of training. Over the entire year the concentrations of serum hormones remained statistically unaltered in both groups. Slight but statistically insignificant increases of 1.2% +/- 0.8% and 2.1% +/- 5.1% were observed in the competitive performances over the year in the endurance-trained and strength-trained groups, respectively. The present findings in the two groups of elite athletes, who differed greatly with regard to the type of physiological loading, demonstrated that the overall hormonal responses both during the most intensive and during prolonged training periods were rather similar and the infrequent small changes remained well within the normal physiological range.(ABSTRACT TRUNCATED AT 250 WORDS)     

Tandem mass spectrometry for on-line fermentation monitoring

Summary Membrane introduction mass spectrometry has been employed for on-line determination of the major products and volatile metabolites ofBacillus polymyxa fermentation. Samples were introduced into the mass spectrometer via a direct insertion membrane probe in which the aqueous solution flowed past a membrane located in the ion source of the mass spectrometer. Concentrations of the products 2,3-butanediol, acetoin, ethanol and acetic acid in fermentation broth were measured by tandem mass spectrometry after permeation through the membrane and ionization by chemical ionization. External standards were employed for quantification and a large linear response range was available for each of the major products observed. Dissolved CO₂ and O₂, as well as CO₂ in the off gases, were also monitored on-line by mass spectrometry. The use of tandem mass spectrometry has allowed the identification of products that were not previously known to be present in measurable amounts.     

Mutant EF-Tu increases missense error in vitro

Summary We have studied the consequences of mutational alteration in the structure of EF-Tu on the missense errors and proofreading activity of bacterial ribosomes in vitro. Our data show that the EF-Tu Bo mutant form of EF-Tu (van der Meide et al. 1983a) is inactive in polypeptide synthesis on the ribosome, even though it binds aminoacyl-tRNA. A second mutant form, EF-Tu Ar (van der Meide et al. 1983a), is active in polypeptide synthesis but supports a much higher messense incorporation with either leucine isoacceptor 2 or leucine isoacceptor 4 in the in vitro system. Further analysis of the kinetic basis of this enhanced missense frequency revealed that the mutation responsible for the alteration in EF-Tu Ar increases the errors at both the proofreading step and the initial selection. In this respect the effect of this particular mutation is similar to the mode of action of the antibiotic kanamycin (Jelenc and Kurland 1984).     

Human papillomavirus seroprevalence in pregnant women following gender-neutral and girls-only vaccination programs in Finland: A cross-sectional cohort analysis following a cluster randomized trial

BackgroundCervical cancer elimination through human papillomavirus (HPV) vaccination programs requires the attainment of herd effect. Due to its uniquely high basic reproduction number, the vaccination coverage required to achieve herd effect against HPV type 16 exceeds what is attainable in most populations. We have compared how gender-neutral and girls-only vaccination strategies create herd effect against HPV16 under moderate vaccination coverage achieved in a population-based, community-randomized trial.Methods and findingsIn 2007–2010, the 1992–1995 birth cohorts of 33 Finnish communities were randomized to receive gender-neutral HPV vaccination (Arm A), girls-only HPV vaccination (Arm B), or no HPV vaccination (Arm C) (11 communities per trial arm). HPV16/18/31/33/35/45 seroprevalence differences between the pre-vaccination era (2005–2010) and post-vaccination era (2011–2016) were compared between all 8,022 unvaccinated women <23 years old and resident in the 33 communities during 2005–2016 (2,657, 2,691, and 2,674 in Arms A, B, and C, respectively). Post- versus pre-vaccination-era HPV seroprevalence ratios (PRs) were compared by arm. Possible outcome misclassification was quantified via probabilistic bias analysis. An HPV16 and HPV18 seroprevalence reduction was observed post-vaccination in the gender-neutral vaccination arm in the entire study population (PR₁₆ = 0.64, 95% CI 0.10–0.85; PR₁₈ = 0.72, 95% CI 0.22–0.96) and for HPV16 also in the herpes simplex virus type 2 seropositive core group (PR₁₆ = 0.64, 95% CI 0.50–0.81). Observed reductions in HPV31/33/35/45 seroprevalence (PR_31/33/35/45 = 0.88, 95% CI 0.81–0.97) were replicated in Arm C (PR_31/33/35/45 = 0.79, 95% CI 0.69–0.90).ConclusionsIn this study we only observed herd effect against HPV16/18 after gender-neutral vaccination with moderate vaccination coverage. With only moderate vaccination coverage, a gender-neutral vaccination strategy can facilitate the control of even HPV16. Our findings may have limited transportability to other vaccination coverage levels.Trial registrationClinicalTrials.gov number {"type":"clinical-trial","attrs":{"text":"NCT00534638","term_id":"NCT00534638"}}NCT00534638, https://clinicaltrials.gov/ct2/show/{"type":"clinical-trial","attrs":{"text":"NCT00534638","term_id":"NCT00534638"}}NCT00534638.     

Hyperlipidemic rabbit serum reduces recovery of acidic glycosaminoglycans from tissue culture medium

Hyperlipidemic rabbit serum and its lipid extract were found to impair the precipitation of glycosaminoglycans by cetylpyridinium chloride. The inhibition was 60–80% in the case of sulfated glycosaminoglycans and 75–85% in the case of hyaluronic acid. The interfering compounds could be removed by extracting the samples twice with a six-fold volume of ethanol-ether (2:1) for 1 h.     

Offspring Defence in Relation to Litter Size and Age: Experiment in the Bank vole Clethrionomys glareolus

According to parental investment theory, nest defence activity should be related to the reproductive value of the offspring. Alternative hypotheses suggest that defence activity may, for example, depend upon the conspicuousness of the young. Studies concerning this topic have been carried out almost exclusively on birds and experimental data on the diversity of organisms is lacking. Bank voles Clethrionomys glareolus were used to study the effects of the number and age of offspring upon the pup defence activity of mothers. Male bank voles are infanticidal and thus an adult male was used as a predator. Defence trials were conducted in the laboratory and filmed for subsequent analysis. Litter sizes were divided into three treatment groups: reduced (−2 pups), control (±0 pups) and enlarged (+2 pups). In order to study the effect of offspring age upon maternal defence activity the trials were conducted twice: when the pups were 3 and 8 days old. Defence activity increased with the number of offspring and enlarged litters were most actively defended. This result supports parental investment theory and conclusions drawn by earlier studies of birds. However, in contrast to the conclusions of earlier studies, older offspring were defended less than the younger ones. Whilst new-born pups are totally defenceless against predators their vulnerability decreases as they age. Therefore, we suggest that maternal aggression in female bank voles is related to the value as well as to the vulnerability of the offspring. The validity of this explanation and the determinants of parental investment decisions in small mammals in general deserve further study. This revised version was published online in July 2006 with corrections to the Cover Date.     

On the effect of the concentration profile of red cells on blood flow in the artery with stenosis

The effects of the viscosity-concentration dependence and of the concentration profile on blood flow through a vessel with stenosis have been studied. The flow resistance and the wall shear stress have been found to be smaller than in the two-fluid model with constant viscosities.