Louse-borne relapsing fever—a systematic review and analysis of the literature: part 2— mortality, Jarisch–Herxheimer reaction, impact on pregnancy

Louse-borne relapsing fever (LBRF) is a classical epidemic disease, which in the past was associated with war, famine, poverty, forced migration, and crowding under poor hygienic conditions around the world. The disease’s causative pathogen, the spirochete bacterium Borrelia recurrentis, is confined to humans and transmitted by a single vector, the human body louse Pediculus humanus corporis. Since the disease was at its peak before the days of modern medicine, many of its aspects have never been formally studied and to date remain incompletely understood. In order to shed light on some of these aspects, we have systematically reviewed the accessible literature on LBRF since the recognition of its mode of transmission in 1907, and summarized the existing data on mortality, Jarisch–Herxheimer reaction (JHR), and impact on pregnancy. Publications were identified by using a predefined search strategy of electronic databases and a subsequent review of the reference lists of the obtained publications. All publications reporting patients with a confirmed diagnosis of LBRF published in English, French, German, and Spanish since 1907 were included. Data extraction followed a predefined protocol and included a grading system to judge the certainty of the diagnosis of reported cases. The high mortality rates often found in literature are confined to extreme scenarios. The case fatality rate (CFR) of untreated cases is on average significantly lower than frequently assumed. In recent years, a rise in the overall CFRs is documented, for which reasons remain unknown. Lacking standardized criteria, a clear diagnostic threshold defining antibiotic treatment-induced JHR does not exist. This explains the wide range of occurrence rates found in literature. Pre-antibiotic era data suggest the existence of a JHR-like reaction also in cases treated with arsenicals and even in untreated cases. LBRF-related adverse outcomes are observed in 3 out of 4 pregnancies

Spectral features of Earth-like planets and their detectability at different orbital distances around F, G, and K-type stars

We investigate the spectral appearance of Earth-like exoplanets in the HZ of different main sequence stars at different orbital distances. We furthermore discuss for which of these scenarios biomarker absorption bands may be detected during primary or secondary transit with near-future telescopes and instruments.We analyze the spectra taking into account different filter bandpasses of two photometric instruments planned to be mounted to the JWST. We analyze in which filters and for which scenarios molecular absorption bands are detectable when using the space-borne JWST or the ground-based telescope E-ELT. Absorption bands of CO2, H2O, CH4 and O3 are clearly visible in high-resolution spectra as well as in the filters of photometric instruments. However, only during primary eclipse bands of CO2, H2O and O3 are detectable for all scenarios when using photometric instruments and an E-ELT telescope setup. CH4 is only detectable at the outer HZ of the K star since here the atmospheric modeling results in very high abundances. Since the detectable CO2 and H2O bands overlap, separate bands need to be observed to prove their existence in the atmosphere. In order to detect H2O in a separate band, a S/N>7 needs to be achieved for E-ELT observations, e.g. by co-adding at least 10 transit observations. Using a spaceborne telescope like the JWST enables the detection of CO2 at 4.3mu, which is not possible for ground-based observations due to the Earth's atmospheric absorption. Hence combining observations of spaceborne and groundbased telescopes might allow to detect the presence of the biomarker molecule O3 and the related compounds H2O and CO2 in a planetary atmosphere. Other absorption bands using the JWST can only be detected for much higher S/Ns, which is not achievable by just co-adding transit observations since this would be far beyond the planned mission time of JWST.(abridged)Comment: 15 pages, 8 figure

Chroniques des recherches sur le mont Beuvray 2009-2012

Cet article propose un bilan succinct des recherches effectuées sur le Mont Beuvray et dans ses environs entre 2009 et 2012 dans le cadre du programme international de recherche consacré à l’oppidum de Bibracte. De nouveaux acquis concernent l’ensemble monumental dit « îlot des Grandes Forges » et la domus PC1, le système de fortifications (enclos sommital du Porrey), la tranchée minière de la Pâture des Grangerands… On retiendra surtout l’ouverture d’un nouveau secteur de fouille très prometteur qui englobe le replat central du Parc aux Chevaux et l’éminence du Theurot de la Roche, avec des vestiges variés qui dénotent des espaces privés et publics, et une phase tardive d’aménagement qui semble être restée inachevée.Les recherches consacrées au territoire de Bibracte n’ont pas été en reste avec, par exemple, la caractérisation d’une vaste agglomération du Ier siècle avant notre ère aux Sources de l’Yonne, à 4 km des remparts de l’oppidum.The article offers a summary of the research carried out on Mont Beuvray and its surrounding area between 2009 and 2012 within the international research programme dedicated to the oppidum of Bibracte. New findings concern the monumental “îlot des Grandes Forges” and the domus PC1, the fortifications system (enclosure at the top of Le Porrey), the mine trench of the Pâture des Grangerands, etc. An important development is the opening of a new and very promising excavation section that rings the central shelf of the Parc aux Chevaux and the hill of the Theurot de la Roche, where various traces indicate private and public spaces, and a late phase of organisation that seems to have remained uncompleted.Research in the zone of Bibracte has not been neglected, with, for example, the delineation of a vast agglomeration from the 1st century BC at Les Sources de l’Yonne 4 kilometres from the ramparts of the oppidum.Dieser Artikel schlägt eine kurze Bilanz der Forschungen vor, die zwischen 2009 und 2012 auf dem Mont Beuvray und seiner Umgebung im Rahmen des dem Oppidum von Bibracte gewidmeten internationalen Forschungsprogramms durchgeführt wurden. Neue Erkenntnisse zu dem monumentalen Ensemble in der îlot des Grandes Forges und der domus PC1, dem System des Befestigungswerks (Umfriedung auf dem Gipfelplateau Le Porrey), der Bergwerksgrube der Pâture des Grangerands… Besonders zu bemerken ist die Eröffnung eines neuen sehr vielversprechenden Grabungssektors, der die zentrale Plattform des Parc aux Chevaux umfasst sowie den Gipfel des Theurot de la Roche mit unterschiedlichen Resten, die von öffentlichen und privaten Bereichen zeugen, zudem wurde eine späte Umgestaltungsphase erkannt, die anscheinend nicht fertiggestellt worden war.Auch die dem Territorium von Bibracte gewidmeten Forschungen ergaben interessante Erkenntnisse. Im Quellbereich der Yonne, 4 km von den Wällen des oppidums entfernt wurde z.B. eine größere Ortschaft des 1. Jh. v. Chr. erkannt

Chroniques des recherches sur le mont Beuvray 2009-2012

Cet article propose un bilan succinct des recherches effectuées sur le Mont Beuvray et dans ses environs entre 2009 et 2012 dans le cadre du programme international de recherche consacré à l’oppidum de Bibracte. De nouveaux acquis concernent l’ensemble monumental dit « îlot des Grandes Forges » et la domus PC1, le système de fortifications (enclos sommital du Porrey), la tranchée minière de la Pâture des Grangerands… On retiendra surtout l’ouverture d’un nouveau secteur de fouille très prometteur qui englobe le replat central du Parc aux Chevaux et l’éminence du Theurot de la Roche, avec des vestiges variés qui dénotent des espaces privés et publics, et une phase tardive d’aménagement qui semble être restée inachevée.Les recherches consacrées au territoire de Bibracte n’ont pas été en reste avec, par exemple, la caractérisation d’une vaste agglomération du Ier siècle avant notre ère aux Sources de l’Yonne, à 4 km des remparts de l’oppidum.The article offers a summary of the research carried out on Mont Beuvray and its surrounding area between 2009 and 2012 within the international research programme dedicated to the oppidum of Bibracte. New findings concern the monumental “îlot des Grandes Forges” and the domus PC1, the fortifications system (enclosure at the top of Le Porrey), the mine trench of the Pâture des Grangerands, etc. An important development is the opening of a new and very promising excavation section that rings the central shelf of the Parc aux Chevaux and the hill of the Theurot de la Roche, where various traces indicate private and public spaces, and a late phase of organisation that seems to have remained uncompleted.Research in the zone of Bibracte has not been neglected, with, for example, the delineation of a vast agglomeration from the 1st century BC at Les Sources de l’Yonne 4 kilometres from the ramparts of the oppidum.Dieser Artikel schlägt eine kurze Bilanz der Forschungen vor, die zwischen 2009 und 2012 auf dem Mont Beuvray und seiner Umgebung im Rahmen des dem Oppidum von Bibracte gewidmeten internationalen Forschungsprogramms durchgeführt wurden. Neue Erkenntnisse zu dem monumentalen Ensemble in der îlot des Grandes Forges und der domus PC1, dem System des Befestigungswerks (Umfriedung auf dem Gipfelplateau Le Porrey), der Bergwerksgrube der Pâture des Grangerands… Besonders zu bemerken ist die Eröffnung eines neuen sehr vielversprechenden Grabungssektors, der die zentrale Plattform des Parc aux Chevaux umfasst sowie den Gipfel des Theurot de la Roche mit unterschiedlichen Resten, die von öffentlichen und privaten Bereichen zeugen, zudem wurde eine späte Umgestaltungsphase erkannt, die anscheinend nicht fertiggestellt worden war.Auch die dem Territorium von Bibracte gewidmeten Forschungen ergaben interessante Erkenntnisse. Im Quellbereich der Yonne, 4 km von den Wällen des oppidums entfernt wurde z.B. eine größere Ortschaft des 1. Jh. v. Chr. erkannt

Quantification of short and long asbestos fibers to assess asbestos exposure: a review of fiber size toxicity.

International audienceThe fibrogenicity and carcinogenicity of asbestos fibers are dependent on several fiber parameters including fiber dimensions. Based on the WHO (World Health Organization) definition, the current regulations focalise on long asbestos fibers (LAF) (Length: L ≥ 5 μm, Diameter: D  3). However air samples contain short asbestos fibers (SAF) (L < 5 μm). In a recent study we found that several air samples collected in buildings with asbestos containing materials (ACM) were composed only of SAF, sometimes in a concentration of ≥10 fibers.L-1. This exhaustive review focuses on available information from peer-review publications on the size-dependent pathogenetic effects of asbestos fibers reported in experimental in vivo and in vitro studies. In the literature, the findings that SAF are less pathogenic than LAF are based on experiments where a cut-off of 5 μm was generally made to differentiate short from long asbestos fibers. Nevertheless, the value of 5 μm as the limit for length is not based on scientific evidence, but is a limit for comparative analyses. From this review, it is clear that the pathogenicity of SAF cannot be completely ruled out, especially in high exposure situations. Therefore, the presence of SAF in air samples appears as an indicator of the degradation of ACM and inclusion of their systematic search should be considered in the regulation. Measurement of these fibers in air samples will then make it possible to identify pollution and anticipate health risk

Early markers of airways inflammation and occupational asthma: Rationale, study design and follow-up rates among bakery, pastry and hairdressing apprentices

<p>Abstract</p> <p>Background</p> <p>Occupational asthma is a common type of asthma caused by a specific agent in the workplace. The basic alteration of occupational asthma is airways inflammation. Although most patients with occupational asthma are mature adults, there is evidence that airways inflammation starts soon after inception of exposure, including during apprenticeship. Airways hyper responsiveness to methacholine is a valid surrogate marker of airways inflammation, which has proved useful in occupational epidemiology. But it is time-consuming, requires active subject's cooperation and is not readily feasible. Other non-invasive and potentially more useful tests include the forced oscillation technique, measurement of fraction exhaled nitric oxide, and eosinophils count in nasal lavage fluid.</p> <p>Methods and design</p> <p>This study aims to investigate early development of airways inflammation and asthma-like symptoms in apprentice bakers, pastry-makers and hairdressers, three populations at risk of occupational asthma whose work-related exposures involve agents of different nature. The objectives are to (i) examine the performance of the non-invasive tests cited above in detecting early airways inflammation that might eventually develop into occupational asthma; and (ii) evaluate whether, and how, constitutional (e.g. atopy) and behavioural (e.g. smoking) risk factors for occupational asthma modulate the effects of allergenic and/or irritative substances involved in these occupations. This paper presents the study rationale and detailed protocol.</p> <p>Discussion</p> <p>Among 441 volunteers included at the first visit, 354 attended the fourth one. Drop outs were investigated and showed unrelated to the study outcome. Sample size and follow-up participation rates suggest that the data collected in this study will allow it to meet its objectives.</p

Co-exposures to physical and psychosocial work factors increase the occurrence of workplace injuries among French care workers

ObjectiveThe aim of this study was to analyze the effect of co-exposures to physical and psychosocial factors (PSF) regarding the incidence of workplace injuries (WI) among care workers. Additional objective was to identify the work factors associated with the co-exposure combinations leading to the highest rates of WI.MethodsThe study sample consisted of 4,418 care workers participating to the French Working Conditions Survey both in 2013 and 2016. WI were assessed during the 4-year follow-up by matching the databases of the National Health Insurance Funds' compensation system. We assessed exposure for physical factors and PSF using factorial analyses and hierarchical clustering. We implemented a Poisson regression model with the WI incidence as the outcome and the clusters as independent variables of interest. Logistic regression model allowed identifying the work factors that predicted co-exposure combinations with a WI rate &gt; 40%.ResultsWI were highly related to both physical and psychosocial exposures. With low exposure to one or the other, there was no increased risk of WI. Physical factors and PSF potentiated each other and their co-exposure significantly increased the risk of WI, with model predicted rates per 1,000 persons-year for those most exposed to physical risk of 14.6 [4.5–24.8] with low PSF and 38.0 [29.8–46.3] with high PSF. Work factors that predicted co-exposure combinations with a rate &gt; 40 WI% were: working as nursing assistant or hospital services officer, lack of predictability and flexibility of schedules, overtime, controlled schedules, work-family imbalance and insufficient preventive measures.ConclusionsOur findings highlight the need to take into account psychosocial factors in addition of only considering physical factors when analyzing WI occurrence, as usually done. Prevention actions must be taken to reduce both physical and psychosocial exposure. These results provide keys points for the prevention of WI among care workers

Warming the early Earth - CO2 reconsidered

Despite a fainter Sun, the surface of the early Earth was mostly ice-free. Proposed solutions to this so-called "faint young Sun problem" have usually involved higher amounts of greenhouse gases than present in the modern-day atmosphere. However, geological evidence seemed to indicate that the atmospheric CO2 concentrations during the Archaean and Proterozoic were far too low to keep the surface from freezing. With a radiative-convective model including new, updated thermal absorption coefficients, we found that the amount of CO2 necessary to obtain 273 K at the surface is reduced up to an order of magnitude compared to previous studies. For the late Archaean and early Proterozoic period of the Earth, we calculate that CO2 partial pressures of only about 2.9 mb are required to keep its surface from freezing which is compatible with the amount inferred from sediment studies. This conclusion was not significantly changed when we varied model parameters such as relative humidity or surface albedo, obtaining CO2 partial pressures for the late Archaean between 1.5 and 5.5 mb. Thus, the contradiction between sediment data and model results disappears for the late Archaean and early Proterozoic.Comment: 53 pages, 4 tables, 11 figures, published in Planetary and Space Scienc

Modelling prevalence and incidence of fibrosis and pleural plaques in asbestos-exposed populations for screening and follow-up: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>CT-Scan is currently under assessment for the screening of asbestos-related diseases. However, to date no consensus exists as to how to select high-risk asbestos-exposed populations suitable for such screening programs. The objective of this study is to select the most relevant exposure variables for the prediction of pleural plaques and asbestosis in order to guide clinicians in their use of CT-Scan.</p> <p>Methods</p> <p>A screening program of non malignant asbestos-related diseases by CT-scan was conducted among asbestos-exposed volunteers in France. Precise assessments of asbestos exposure were obtained by occupational hygiene measurements and a job-exposure matrix. Several parameters were calculated (time since first exposure, duration, intensity and cumulative exposure to asbestos). Predictive parameters of prevalence and incidence were then estimated by standard logistic and a complementary log-log regression models.</p> <p>Results</p> <p>1011 subjects were recruited in this screening program among them 474 (46.9%) presented with pleural plaques and 61 (6.0%) with interstitial changes compatible with asbestosis on CT-scan. Time since first exposure (p < 0.0001) and either cumulative or mean exposure (p < 0.0001) showed independent associations with both pleural plaques and asbestosis prevalence and pleural plaques incidence. Modelling incidence of pleural plaques showed a 0.8% to 2.4% yearly increase for a mean exposure of 1 f/ml.</p> <p>Conclusion</p> <p>Our findings confirmed the role played by time since first exposure and dose but not duration in asbestos-related diseases. We recommend to include these parameters in high-risk populations suitable for screening of these diseases. Short-periodicity of survey of pleural plaques by CT-Scan seemed not to be warranted.</p

Recommendations for the application and follow-up of quality controls in medical laboratories

This is a translation of the paper “Recommendations for the application and follow-up of quality controls in medical biology laboratories” published in French in the journal Annales de Biologie Clinique (Recommandations pour la mise en place et le suivi des contrôles de qualité dans les laboratoires de biologie médicale. Ann Biol Clin (Paris). 2019;77:577-97.). The recommendations proposed in this document are the result of work conducted jointly by the Network of Accredited Medical Laboratories (LABAC), the French Society of Medical Biology (SFBC) and the Federation of Associations for External Quality Assessment (FAEEQ). The different steps of the implementation of quality controls, based on a risk analysis, are described. The changes of reagent or internal quality control (IQC) materials batches, the action to be taken in case of non-conform IQC results, the choice of external quality assessment (EQA) scheme and interpretation of their results as well as the new issue of analyses performed on several automatic systems available in the same laboratory are discussed. Finally, the concept of measurement uncertainty, the robustness of the methods as well as the specificities of near-patient testing and rapid tests are described. These recommendations cannot apply for all cases we can find in medical laboratories. The implementation of an objective alternative strategy, supported with documented evidence, might be equally considered