Genome-wide transposon insertion scanning of environmental survival functions in the polycyclic aromatic hydrocarbon degrading bacterium Sphingomonas wittichii RW1.

Sphingomonas wittichii RW1 is a dibenzofuran and dibenzodioxin-degrading bacterium with potentially interesting properties for bioaugmentation of contaminated sites. In order to understand the capacity of the microorganism to survive in the environment we used a genome-wide transposon scanning approach. RW1 transposon libraries were generated with around 22 000 independent insertions. Libraries were grown for an average of 50 generations (five successive passages in batch liquid medium) with salicylate as sole carbon and energy source in presence or absence of salt stress at -1.5 MPa. Alternatively, libraries were grown in sand with salicylate, at 50% water holding capacity, for 4 and 10 days (equivalent to 7 generations). Library DNA was recovered from the different growth conditions and scanned by ultrahigh throughput sequencing for the positions and numbers of inserted transposed kanamycin resistance gene. No transposon reads were recovered in 579 genes (10% of all annotated genes in the RW1 genome) in any of the libraries, suggesting those to be essential for survival under the used conditions. Libraries recovered from sand differed strongly from those incubated in liquid batch medium. In particular, important functions for survival of cells in sand at the short term concerned nutrient scavenging, energy metabolism and motility. In contrast to this, fatty acid metabolism and oxidative stress response were essential for longer term survival of cells in sand. Comparison to transcriptome data suggested important functions in sand for flagellar movement, pili synthesis, trehalose and polysaccharide synthesis and putative cell surface antigen proteins. Interestingly, a variety of genes were also identified, interruption of which cause significant increase in fitness during growth on salicylate. One of these was an Lrp family transcription regulator and mutants in this gene covered more than 90% of the total library after 50 generations of growth on salicylate. Our results demonstrate the power of genome-wide transposon scanning approaches for analysis of complex traits.

A mutation in the gene encoding the vaccinia virus 37,000-M(r) protein confers resistance to an inhibitor of virus envelopment and release.

Plaque formation in vaccinia virus is inhibited by the compound N1-isonicotinoyl-N2-3-methyl-4-chlorobenzoylhydrazine (IMCBH). We have isolated a mutant virus that forms wild-type plaques in the presence of the drug. Comparison of wild-type and mutant virus showed that both viruses produced similar amounts of infectious intracellular naked virus in the presence of the drug. In contrast to the mutant, no extracellular enveloped virus was obtained from IMCBH-treated cells infected with wild-type virus. Marker rescue experiments were used to map the mutation conferring IMCBH resistance to the mutant virus. The map position coincided with that of the gene encoding the viral envelope antigen of M(r) 37,000. Sequence analysis of both wild-type and mutant genes showed a single nucleotide change (G to T) in the mutant gene. In the deduced amino acid sequence, the mutation changes the codon for an acidic Asp residue in the wild-type gene to one for a polar noncharged Tyr residue in the mutant.

Follicular lymphoma at relapse after rituximab containing regimens: comparison of time to event intervals prior to and after (90) Y-ibritumomab-tiuxetan.

Radioimmunotherapies with Zevalin® (RIT-Z) showed encouraging results in patients with relapsed/refractory follicular lymphoma (FL), leading frequently to failure-free intervals longer than those achieved by the last previous therapy. We compared time-to-event variables obtained before and after RIT-Z in patients with relapsed FL, previously exposed to rituximab. All patients with relapsed non-transformed, non-refractory, non-rituximab-naïve FL who have been treated with RIT-Z in two different centres in Europe were included. Staging and response were assessed by contrast-enhanced CT in all patients; PET/CT was performed according to local availability. Event-free survival (EFS) and time to next treatment (TTNT) following the last previous therapy and after RIT-Z were compared. Pre-therapy characteristics were tested in univariate analyses for prediction of outcomes. A description of the patterns of relapse was also provided. Among 70 patients treated, only 16 fulfilled the inclusion criteria. They were treated with a median of 3 prior lines of chemo-immunotherapies, including a median of 2 rituximab-containing regimens; 6 patients had undergone myeloablative chemotherapy with autologous stem cell rescue (ASCT). Overall response rates were 10 (62%) CR/CRu, 3 (19%) PR and 3 (19%) PD; response rates were similar in patients with prior ASCT. After RIT-Z only few patients obtained EFS and TTNT longer than after the last previous therapy. All four patients receiving rituximab maintenance were without progression 12 months after RIT-Z. Relapses occurred in both previously and newly involved sites; a significant association was found between the number of pathologic sites involved prior to RIT-Z and subsequent TTNT. Despite the excellent response rate, the duration of response was shorter than the previous one confirming the known trend of relapses to occur earlier after subsequent treatments. Rituximab maintenance after RIT-Z showed encouraging results in terms of prolonging EFS, warranting further studies. Copyright © 2010 John Wiley & Sons, Ltd.

Sex-stratified genome-wide association studies including 270,000 individuals show sexual dimorphism in genetic loci for anthropometric traits.

Given the anthropometric differences between men and women and previous evidence of sex-difference in genetic effects, we conducted a genome-wide search for sexually dimorphic associations with height, weight, body mass index, waist circumference, hip circumference, and waist-to-hip-ratio (133,723 individuals) and took forward 348 SNPs into follow-up (additional 137,052 individuals) in a total of 94 studies. Seven loci displayed significant sex-difference (FDR<5%), including four previously established (near GRB14/COBLL1, LYPLAL1/SLC30A10, VEGFA, ADAMTS9) and three novel anthropometric trait loci (near MAP3K1, HSD17B4, PPARG), all of which were genome-wide significant in women (P<5×10(-8)), but not in men. Sex-differences were apparent only for waist phenotypes, not for height, weight, BMI, or hip circumference. Moreover, we found no evidence for genetic effects with opposite directions in men versus women. The PPARG locus is of specific interest due to its role in diabetes genetics and therapy. Our results demonstrate the value of sex-specific GWAS to unravel the sexually dimorphic genetic underpinning of complex traits.

Dating human skeletal remains using a radiometric method: Biogenic versus diagenetic (90)Sr and (210)Pb in vertebrae.

In forensic science, there is a strong interest in determining the post-mortem interval (PMI) of human skeletal remains up to 50 years after death. Currently, there are no reliable methods to resolve PMI, the determination of which relies almost exclusively on the experience of the investigating expert. Here we measured (90)Sr and (210)Pb ((210)Po) incorporated into bones through a biogenic process as indicators of the time elapsed since death. We hypothesised that the activity of radionuclides incorporated into trabecular bone will more accurately match the activity in the environment and the food chain at the time of death than the activity in cortical bone because of a higher remodelling rate. We found that determining (90)Sr can yield reliable PMI estimates as long as a calibration curve exists for (90)Sr covering the studied area and the last 50 years. We also found that adding the activity of (210)Po, a proxy for naturally occurring (210)Pb incorporated through ingestion, to the (90)Sr dating increases the reliability of the PMI value. Our results also show that trabecular bone is subject to both (90)Sr and (210)Po diagenesis. Accordingly, we used a solubility profile method to determine the biogenic radionuclide only, and we are proposing a new method of bone decontamination to be used prior to (90)Sr and (210)Pb dating.

Urgences gériatriques pré-hospitalières: étude rétrospective des interventions des ambulances et des SMUR sur 5 ans

Introduction: Les personnes âgées de 65 ans ou plus représentent 15% de la population générale dans les pays occidentaux. Le vieillissement de cette population va accroître encore cette proportion pour atteindre 20% dès 2030. Les urgences gériatriques représentent environ 15% des admissions dans les services d'accueil et de traitement des urgences (SAU), mais peu de données pré-hospitalières existent. Méthode: Etude rétrospective entre 2003 et 2007 des interventions des services d'urgences pré-hospitaliers (ambulances, SMUR) de notre région (env. 670'000 habitants) à partir des rapports de missions effectués pour chaque intervention par ces entités (n = 42'000). Extraction des données démographiques (âge, sexe), des lieux de prise en charge, des degrés de gravité (score NACA) et des catégories diagnostiques de la population âgée de 65 ans ou plus. Résultats: Les urgences gériatriques représentent entre 40 et 50% des interventions pré-hospitalières totales (ambulances, SMUR). Ces chiffres sont encore entre 4 et 8% pour les sujets très âgés de 90 ans et plus. Le sexe ratio H : F est de 0,72 pour les interventions des ambulances, alors qu'il est de 1,03 pour celles des SMUR. Le lieu de prise en charge est le domicile dans près de 70% des cas. Près des ¾ des interventions sont bénignes (degrés de gravité NACA 0-3), avec plus de 92% des interventions relevant de problèmes de type maladies (et non d'accidents). Pour les cas pris en charge par les SMUR, près de 70% sont de nature cardio-vasculaires. Discussion: La charge que représente les urgences gériatriques pour le secteur pré-hospitalier n'est pas négligeable et nécessite dès aujourd'hui une réflexion afin de dimensionner ce secteur aux exigences de ce type d'urgences pour le futur proche. Non seulement les moyens (personnel, véhicules, matériel) devront être proportionnés, mais aussi les particularités de la prise en charge, la formation spécifique et les aspects éthiques. Ce dernier aspect qui n'est pas des moindres et les limites de la prise en charge devront également être abordés. Conclusion: Les urgences gériatriques représentent près de la moitié des interventions des services pré-hospitaliers (ambulances, SMUR). Le vieillissement à venir de la population risque de mettre encore plus ces services sous «haute tension» et doit faire réfléchir ses acteurs et ses décideurs à s'adapter à cette évolution incontournable.

Ambulances et SMUR en cas d'urgences vitales au cabinet médical: implications pour la formation et l'équipement du médecin de premier recours

Introduction: Tout praticien est confronté quotidiennement à des urgences. Parmi celles-ci, les urgences vitales peuvent avoir des conséquences majeures pour le patient et pour le praticien. Le but de cette analyse est de déterminer la fréquence de survenue des urgences vitales au cabinet médical qui motivent l'intervention d'une ambulance, avec ou sans médicalisation par un SMUR (Service Mobile d'Urgence et de Réanimation) et d'en évaluer des conséquences en terme de mise en place de procédures, d'équipements ainsi que de formations post-graduée ou continue spécifiques. Matériel et méthode: Etude rétrospective des fiches d'intervention pré-hospitalière des services d'ambulances et des missions des SMUR du canton de Vaud (650'000 habitants) entre 2003 et 2006 pour les missions dont la prise en charge d'un patient a eu lieu dans le cadre d'un cabinet médical. Résultats: Entre 2003 et 2006, 2'224 interventions avec ambulances ont eu lieu dans un des 1'655 cabinet médical vaudois (= 2,3% de l'ensemble des missions) et, dans >90% des cas, dans un délai de 20 minutes. Parmi les interventions, on relève les urgences suivantes (n =, % des interventions): cardio-vasculaires: 755 (= 33,9%), dont 17 arrêts cardio-respiratoires (ACR); respiratoires: 165 (= 7,4%); neurologiques: 138 (= 6,2%); psychiatriques: 129 (= 5,8%); traumatologiques: 475 (= 21,4%), dont 261 (= 54,9%) concernent les extrémités; diverses: 205 (= 9,5%); autres: 359 (= 16,1%). Sur ces interventions, 634 (= 28,5%) ont bénéficié d'une médicalisation par un SMUR, dont 440 (= 70% des missions SMUR au cabinet) pour des urgences cardio-vasculaires. Il y a eu 6 cas de décès au cabinet. Discussion: Les urgences cardio-vasculaires au cabinet représentent un tiers des interventions faisant appel à une ambulance, mais plus des deux tiers des interventions nécessitant une médicalisation, soit plus que pour les autres sites d'interventions médicalisées dans la communauté (46%). Conclusions: Les urgences vitales au cabinet médical ne sont pas négligeable, peuvent avoir des conséquences lourdes (ACR, décès) et perturber significativement son fonctionnement. Dès lors, une formation appropriée tant pour le médecin que pour son personnel, ainsi qu'un équipement adéquat (par ex. salle équipée avec défibrillateur, appareil d'aérosol, attelles pour les extrémités) devraient être encouragés et généralisés auprès du corps médical.

Self-selection and risk selection on the Swiss health insurance market

Abstract This thesis presents three empirical studies in the field of health insurance in Switzerland. First we investigate the link between health insurance coverage and health care expenditures. We use claims data for over 60 000 adult individuals covered by a major Swiss Health Insurance Fund, followed for four years; the data show a strong positive correlation between coverage and expenditures. Two methods are developed and estimated in order to separate selection effects (due to individual choice of coverage) and incentive effects ("ex post moral hazard"). The first method uses the comparison between inpatient and outpatient expenditures to identify both effects and we conclude that both selection and incentive effects are significantly present in our data. The second method is based on a structural model of joint demand of health care and health insurance and makes the most of the change in the marginal cost of health care to identify selection and incentive effects. We conclude that the correlation between insurance coverage and health care expenditures may be decomposed into the two effects: 75% may be attributed to selection, and 25 % to incentive effects. Moreover, we estimate that a decrease in the coinsurance rate from 100% to 10% increases the marginal demand for health care by about 90% and from 100% to 0% by about 150%. Secondly, having shown that selection and incentive effects exist in the Swiss health insurance market, we present the consequence of this result in the context of risk adjustment. We show that if individuals choose their insurance coverage in function of their health status (selection effect), the optimal compensations should be function of the se- lection and incentive effects. Therefore, a risk adjustment mechanism which ignores these effects, as it is the case presently in Switzerland, will miss his main goal to eliminate incentives for sickness funds to select risks. Using a simplified model, we show that the optimal compensations have to take into account the distribution of risks through the insurance plans in case of self-selection in order to avoid incentives to select risks.Then, we apply our propositions to Swiss data and propose a simple econometric procedure to control for self-selection in the estimation of the risk adjustment formula in order to compute the optimal compensations.

Retention half times in the skeleton of plutonium and Sr-90 from above-ground nuclear tests: A retrospective study of the Swiss population

Plutonium and Sr-90 are considered to be among the most radiotoxic nuclides produced by the nuclear fission process. In spite of numerous studies on mammals and humans there is still no general agreement on the retention half time of both radionuclides in the skeleton in the general population. Here we determined plutonium and Sr-90 in human vertebrae in individuals deceased between 1960 and 2004 in Switzerland. Plutonium was measured by sensitive SF-ICP-MS techniques and Sr-90 by radiometric methods. We compared our results to the ones obtained for other environmental compartments to reveal the retention half time of NBT fallout Pu-239 and Sr-90 in trabecular bones of the Swiss population. Results show that plutonium has a retention half time of 40 +/- 14 years. In contrast Sr-90 has a shorter retention half time of 13.5 +/- 1.0 years. Moreover Sr-90 retention half time in vertebrae is shown to be linked to the retention half time in food and other environmental compartments. These findings demonstrate that the renewal of the vertebrae through calcium homeostatic control is faster for Sr-90 excretion than for plutonium excretion. The precise determination of the retention half time of plutonium in the skeleton will improve the biokinetic model of plutonium metabolism in humans. (C) 2010 Elsevier Ltd. All rights reserved.

Potential impact of single-risk-factor versus total risk management for the prevention of cardiovascular events in Seychelles.

OBJECTIVE: To assess the prevalence of cardiovascular (CV) risk factors in Seychelles, a middle-income African country, and compare the cost-effectiveness of single-risk-factor management (treating individuals with arterial blood pressure >/= 140/90 mmHg and/or total serum cholesterol >/= 6.2 mmol/l) with that of management based on total CV risk (treating individuals with a total CV risk >/= 10% or >/= 20%).METHODS: CV risk factor prevalence and a CV risk prediction chart for Africa were used to estimate the 10-year risk of suffering a fatal or non-fatal CV event among individuals aged 40-64 years. These figures were used to compare single-risk-factor management with total risk management in terms of the number of people requiring treatment to avert one CV event and the number of events potentially averted over 10 years. Treatment for patients with high total CV risk (>/= 20%) was assumed to consist of a fixed-dose combination of several drugs (polypill). Cost analyses were limited to medication.FINDINGS: A total CV risk of >/= 10% and >/= 20% was found among 10.8% and 5.1% of individuals, respectively. With single-risk-factor management, 60% of adults would need to be treated and 157 cardiovascular events per 100 000 population would be averted per year, as opposed to 5% of adults and 92 events with total CV risk management. Management based on high total CV risk optimizes the balance between the number requiring treatment and the number of CV events averted.CONCLUSION: Total CV risk management is much more cost-effective than single-risk-factor management. These findings are relevant for all countries, but especially for those economically and demographically similar to Seychelles.

Subgroup-specific structural variation across 1,000 medulloblastoma genomes.

Medulloblastoma, the most common malignant paediatric brain tumour, is currently treated with nonspecific cytotoxic therapies including surgery, whole-brain radiation, and aggressive chemotherapy. As medulloblastoma exhibits marked intertumoural heterogeneity, with at least four distinct molecular variants, previous attempts to identify targets for therapy have been underpowered because of small samples sizes. Here we report somatic copy number aberrations (SCNAs) in 1,087 unique medulloblastomas. SCNAs are common in medulloblastoma, and are predominantly subgroup-enriched. The most common region of focal copy number gain is a tandem duplication of SNCAIP, a gene associated with Parkinson's disease, which is exquisitely restricted to Group 4α. Recurrent translocations of PVT1, including PVT1-MYC and PVT1-NDRG1, that arise through chromothripsis are restricted to Group 3. Numerous targetable SCNAs, including recurrent events targeting TGF-β signalling in Group 3, and NF-κB signalling in Group 4, suggest future avenues for rational, targeted therapy.

Arthrogryposis multiplexa congenita: an epidemiologic study of nearly 9 million births in 24 EUROCAT registers.

OBJECTIVE: To examine the occurrence of arthrogryposis multiplex congenita (AMC) in Europe and to identify possible risk factors. STUDY DESIGN: Retrospective population-based epidemiological study using EUROCAT congenital anomaly registries. The study population included all cases of AMC (based on WHO ICD-9 or ICD-10 codes) that were livebirths (LB), fetal deaths (FD) from 20 weeks gestation and underwent termination of pregnancy for fetal anomaly (TOPFA), 1980-2006. RESULTS: Among 8.9 million births covered by 24 EUROCAT congenital anomaly registries, 757 AMC cases were reported. This gives a prevalence of 8.5 per 100,000. Five hundred and four (67%) AMC cases were LB, 199 (26%) cases were TOPFA, and FD occurred in 54 (7%) cases. First week survival status was known for 381 of the 504 LB (76%), of whom 87 (23%) died within the first week of life. Perinatal mortality associated with AMC was 32%. Two hundred and eighty-two (37%) cases had isolated AMC, 90 (12%) had additional syndrome or chromosomal anomalies and 385 (51%) had other major malformations. The same or similar anomaly was reported in 13% of siblings and in 12% of the mother's own family background. Information on prenatal testing was available for 521 cases of which 360 tested positive for a congenital anomaly, representing a sensitivity of 69%. Information on maternal illness before and during pregnancy and medication use in the first trimester was available for approximately a third of the mothers, of whom the vast majority reported no maternal illness or medication use. CONCLUSION: AMC is a rare occurrence, with a reported prevalence of 1:12,000. In this study, while information on potential risk factors such as maternal disease or maternal use of drugs was limited, they did not appear to be associated with the occurrence of AMC. AMC was lethal in a third of cases, either in utero or during the first week of life, although this may not be solely attributed to AMC as most cases had additional malformations.

High constant incidence of second primary colorectal cancer.

Patients who had a colorectal cancer have a 1.5- to 2-fold excess risk of a second colorectal cancer as compared to the general population, the excess being higher at younger age at diagnosis. To further investigate the risk and the age-relation of the incidence of second primary colorectal cancer, we considered 9,389 first colon and rectal cancers registered in the Vaud Cancer Registry, Switzerland, between 1974 and 2008, and followed-up to the end of 2008 for a total of 44,113 person-years. There were 136 second colorectal cancers versus 90.5 expected, corresponding to a standardized incidence ratio (SIR) of 1.5 (95% confidence interval, CI, 1.3-1.8). The SIRs were not heterogeneous between men and women, and in strata of calendar year at diagnosis, duration of follow-up, and subsite. However, the SIR was 7.5 (95% CI 4.2-12.4) for subjects diagnosed below age 50 and declined thereafter to reach 1.0 (95% CI 0.6-1.6) at age 80 or over. Consequently, the incidence of second primary colorectal cancer was stable, and exceedingly high, around 300-400/100,000 between age 30-39 and 70 or over. This age pattern is consistent with the existence of a single mutational event in a population of highly susceptible individuals.