Biome-specific rodent dynamics and hantavirus epidemiologies in Europe

Henttonen, H., Leirs, H., Kallio, E.R., Tersago, K., Voutilainen, L

Serological survey in the Finnish human population implies human-to-human transmission of Ljungan virus or antigenically related viruses

Ljungan virus (LV) is a picornavirus related to human parechoviruses (HPeV). The virus has been found in bank voles (Myodes glareolus) and several other rodent species, and suggested to have zoonotic potential. Thus far, seroepidemiological data on LV infections in humans are scarce. In this study, we aimed to characterize the demographic and geographical distribution of LV-reactive antibodies in Finland, and to investigate its occurrence in patients suspected of having a rodent-borne disease, nephropathia epidemica (NE) caused by Puumala hantavirus (PUUV). Using an immunofluorescence assay (LV strain 145SLG), we screened human sera (n = 1378) and found LV-reactive antibodies in 36% of samples. The probability of possessing LV-reactive antibodies peaked at age of 14 years, suggesting that most infections occur in childhood. The prevalence of LV-reactive antibodies was significantly higher in the urbanized area surrounding Helsinki than in more rural Central Finland. These findings are uncharacteristic of a rodent-borne pathogen, and therefore we consider human-to-human transmission of one or several Ljungan-like viruses as a likely cause for most of the observed antibody responses.Peer reviewe

Effects of 2-year physical activity and dietary intervention on adrenarchal and pubertal development: the PANIC study.

CONTEXT Childhood overweight has been linked to earlier development of adrenarche and puberty, but it remains unknown if lifestyle interventions influence sexual maturation in general populations. OBJECTIVE To investigate if a 2-year lifestyle intervention influences circulating androgen concentrations and sexual maturation in a general population of children. DESIGN AND PARTICIPANTS A 2-year intervention study in which 421 prepubertal and mostly normal-weight 6-9-year-old children were allocated either to a lifestyle intervention group (119 girls, 132 boys) or a control group (84 girls, 86 boys). INTERVENTION A 2-year physical activity and dietary intervention. MAIN OUTCOME MEASURES Serum dehydroepiandrosterone, dehydroepiandrosterone sulfate, androstenedione, and testosterone concentrations, and clinical adrenarchal and pubertal signs. RESULTS The intervention and control groups had no differences in body size and composition, clinical signs of androgen action, and serum androgens at baseline. The intervention attenuated the increase of dehydroepiandrosterone (p = 0.032), dehydroepiandrosterone sulfate (p = 0.001), androstenedione (p = 0.003), and testosterone (p = 0.007) and delayed pubarche (p = 0.038) in boys but it only attenuated the increase of dehydroepiandrosterone (p = 0.013) and dehydroepiandrosterone sulfate (p = 0.003) in girls. These effects of lifestyle intervention on androgens and the development of pubarche were independent of changes in body size and composition but the effects of intervention on androgens were partly explained by changes in fasting serum insulin. CONCLUSIONS A combined physical activity and dietary intervention attenuates the increase of serum androgen concentrations and sexual maturation in a general population of prepubertal and mostly normal-weight children, independently of changes in body size and composition

Yersinia spp. in Wild Rodents and Shrews in Finland

Yersinia enterocolitica and Yersinia pseudotuberculosis are important zoonotic bacteria causing human enteric yersiniosis commonly reported in Europe. All Y. pseudotuberculosis strains are considered pathogenic, while Y. enterocolitica include both pathogenic and nonpathogenic strains which can be divided into six biotypes (1A, 1B, and 2-5) and about 30 serotypes. The most common types causing yersiniosis in Europe are Y. enterocolitica bioserotypes 4/O:3 and 2/O:9. Strains belonging to biotype 1A are considered as nonpathogenic because they are missing important virulence genes like the attachment-invasion-locus (ail) gene in the chromosome and the virulence plasmid. The role of wild small mammals as a reservoir of enteropathogenic Yersinia spp. is still obscure. In this study, the presence of Yersinia spp. was examined from 1840 wild small mammals, including voles, mice, and shrews, trapped in Finland during a 7-year period. We isolated seven Yersinia species. Y. enterocolitica was the most common species, isolated from 8% of the animals; while most of these isolates represented nonpathogenic biotype 1A, human pathogenic bioserotype 2/O:9 was also isolated from a field vole. Y. pseudotuberculosis of bioserotype 1/O:2 was isolated from two shrews. The ail gene, which is typically only found in the isolates of biotypes 1B and 2-5 associated with yersiniosis, was frequently (23%) detected in the nonpathogenic isolates of biotype 1A and sporadically (6%) in Yersinia kristensenii isolates. Our results suggest that wild small mammals, especially voles, may serve as carriers for ail-positive Y. enterocolitica 1A and Y. kristensenii. We also demonstrate that voles and shrews sporadically excrete pYV-positive Y. enterocolitica 2/O:9 and Y. pseudotuberculosis 1/O:2, respectively, in their feces and, thus, can serve as a contamination source for vegetables by contaminating the soil.Peer reviewe

Follicle-Stimulating Hormone Levels and Subclinical Atherosclerosis in Older Postmenopausal Women

Recent studies of perimenopausal women suggest that follicle-stimulating hormone (FSH) levels may be associated with atherosclerosis, independent of estradiol. Whether FSH is related to atherosclerosis in older postmenopausal women, who have completed the menopausal transition, remains unknown. We assessed the relationship of serum FSH and estradiol levels with carotid artery intima-media thickness (IMT) among 587 postmenopausal participants in the Kuopio Ischemic Heart Disease Risk Factor Study (Kuopio, Finland). Participants were aged 53-73 years and not using hormone therapy at baseline (1998-2001). Mean IMT was measured via high-resolution ultrasonography. We observed a significant inverse association between FSH levels and IMT. Mean IMTs among women in quartiles 1-4 of FSH were 0.94 mm, 0.91 mm, 0.87 mm, and 0.85 mm, respectively (P-trend <0.001). After adjustment for age, estradiol, testosterone, body mass index (weight (kg)/height (m)(2)), lipids, and other factors, FSH levels remained significantly associated with IMT (regression coefficients for quartiles 2-4 vs. quartile 1 were -0.038, -0.045, and -0.062, respectively; P-trend = 0.01). Findings were strongest in women aged 64-73 years (P-trend = 0.006) and did not vary by body mass index. In contrast, estradiol levels were not related to IMT. In summary, high postmenopausal FSH levels were associated with a lower atherosclerotic burden, independent of estradiol, adiposity, and other factors. Our findings warrant replication and the further exploration of potential underlying mechanisms.Peer reviewe

Measurement of the top quark mass using the matrix element technique in dilepton final states

We present a measurement of the top quark mass in pp collisions at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron collider. The data were collected by the D0 experiment corresponding to an integrated luminosity of 9.7 fb−1. The matrix element technique is applied to tt events in the final state containing leptons (electrons or muons) with high transverse momenta and at least two jets. The calibration of the jet energy scale determined in the lepton + jets final state of tt decays is applied to jet energies. This correction provides a substantial reduction in systematic uncertainties. We obtain a top quark mass of mt = 173.93 ± 1.84 GeV

Measurement of the inclusive \u3ci\u3ett\u3c/i\u3e production cross section in \u3ci\u3epp\u3c/i\u3e collisions at [?] = 1.96 TeV and determination of the top quark pole mass

The inclusive cross section of top quark-antiquark pairs produced in pp collisions at [?] = 1.96 TeV is measured in the lepton + jets and dilepton decay channels. The data sample corresponds to 9.7 fb−1 of integrated luminosity recorded with the D0 detector during Run II of the Fermilab Tevatron Collider. Employing multivariate analysis techniques we measure the cross section in the two decay channels and we perform a combined cross section measurement. For a top quark mass of 172.5 GeV, we measure a combined inclusive top quark-antiquark pair production cross section of σtt = 7.26 ± 0.13(stat)[?] (syst) pb which is consistent with standard model predictions. We also perform a likelihood fit to the measured and predicted top quark mass dependence of the inclusive cross section, which yields a measurement of the pole mass of the top quark. The extracted value is mt = 172.8 ± 1.1(theo)[?] (exp) GeV

Evidence for Simultaneous Production of \u3ci\u3eJ/ψ\u3c/i\u3e and ϒ Mesons

We report evidence for the simultaneous production of J/ψ and ϒ mesons in 8.1 fb−1 of data collected at [?] = 1.96 TeV by the D0 experiment at the Fermilab pp Tevatron Collider. Events with these characteristics are expected to be produced predominantly by gluon-gluon interactions. In this analysis, we extract the effective cross section characterizing the initial parton spatial distribution, σeff = 2.2 ± 0.7(stat) ± 0.9(syst) mb

[?] lifetime measurement in the \u3ci\u3eCP\u3c/i\u3e-odd decay channel [?] → J/ψ f\u3ci\u3e0\u3c/i\u3e(980)

The lifetime of the [?] meson is measured in the decay channel [?] → J/ψπ+π− with 880 ≤ Mπ+π- - ≤ 1080 MeV / c2, which is mainly a CP-odd state and dominated by the f0 (980) resonance. In 10.4 fb-1 of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the [?] meson is measured to be [?] = 1.70 ± 0.14(stat) ± 0.05(syst) ps. Neglecting CP violation in [?]/[?] mixing, the measurement can be translated into the width of the heavy mass eigenstate of the [?], ΓH = 0.59 ± 0.05(stat) ± 0.02(syst) ps-1

Measurement of top quark polarization in \u3ci\u3ett\u3c/i\u3e lepton + jets final states

We present a measurement of top quark polarization in tt pair production in pp collisions at [?] = 1.96 TeV using data corresponding to 9.7 fb−1 of integrated luminosity recorded with the D0 detector at the Fermilab Tevatron Collider. We consider final states containing a lepton and at least three jets. The polarization is measured through the distribution of lepton angles along three axes: the beam axis, the helicity axis, and the transverse axis normal to the tt production plane. This is the first measurement of top quark polarization at the Tevatron using lepton + jet final states and the first measurement of the transverse polarization in tt production. The observed distributions are consistent with standard model predictions of nearly no polarization