Les prolactinomes représentent les tumeurs hypophysaires hormonodépendantes les plus fréquentes. Elles sont souvent bénigne mais peuvent devenir agressives/envahissantes via des mécanismes inconnus. ...La découverte de marqueurs est donc essentielle pour développer de nouvelles stratégies diagnostiques/pronostiques. Les membres des voies de signalisation TGFβ-Activine/BMP constituent des acteurs importants du/des développement/fonctions adultes hypophysaires, mais leurs rôles dans la tumorigenèse de l’hypophyse restent mal définis. Grâce à un modèle d’allogreffe dérivé d’un prolactinome de rat, nous rapportons que le récepteur des activines ALK7 est exprimé dans les cellules de prolactinomes alors qu’il est absent des cellules saines productrices de prolactine. La validation de ces observations sur une série de tumeurs humaines confirme que l’expression d’ALK7 est également induite chez l’homme. Nos résultats soulignent que les tumeurs exprimant fortement d’ALK7 présentent un index Ki67 de prolifération accrue, un résultat confirmé par l’analyse rétrospective des données cliniques de 38 patients. Ces observations suggèrent l’utilisation d’ALK7 comme un nouveau marqueur candidat de l’agressivité des prolactinomes. Au-delà de ces observations, nos travaux révèlent que l’expression du récepteur ALK7 est retrouvée dans une fraction importante de cellules présentant une expression réduite de prolactine suggérant son implication dans le contrôle de la production de cette hormone. Un résultat confirmé par l’identification d’une sous-population de cellules tumorales n’exprimant pas ALK7 et étant fortement immuno-réactives pour la prolactine. Dans leur ensemble, nos observations suggèrent que la signalisation des activines médiée par ALK7 pourrait donc contribuer à l’hétérogénéité hormonale et à la prolifération accrue des prolactinomes.
Current interferometric gravitational-wave detectors are limited by quantum noise over a wide range of their measurement bandwidth. One method to overcome the quantum limit is the injection of ...squeezed vacuum states of light into the interferometer's dark port. Here, we report on the successful application of this quantum technology to improve the shot noise limited sensitivity of the Advanced Virgo gravitational-wave detector. A sensitivity enhancement of up to 3.2±0.1 dB beyond the shot noise limit is achieved. This nonclassical improvement corresponds to a 5%-8% increase of the binary neutron star horizon. The squeezing injection was fully automated and over the first 5 months of the third joint LIGO-Virgo observation run O3 squeezing was applied for more than 99% of the science time. During this period several gravitational-wave candidates have been recorded.
DNA vaccine evaluation in small animals is hampered by low immunogenicity when the vaccines are delivered using a needle and syringe. To overcome this technical hurdle we tested the possibility that ...a device developed for human intradermal medicine delivery might be adapted to successfully deliver a DNA vaccine to small animals. Disposable syringe jet injection (DSJI) does not currently exist for small animals. However, a commercialized, human intradermal device used to to administer medicines to the human dermis in a 0.1 mL volume was evaluated in Syrian hamsters. Here, we found that hantavirus DNA vaccines administered to hamsters using DSJI were substantially more immunogenic than the same vaccines delivered by needle/syringe or particle mediated epidermal delivery (gene gun) vaccination. By adjusting how the device was used we could deliver vaccine to either subcutaneous tissues, or through the skin into the muscle. RNA and/or antigen expression was detected in epidermal, subepidermal and fibroblast cells. We directly compared six optimized and non-optimized hantavirus DNA vaccines in hamsters. Optimization, including codon-usage and mRNA stability, did not necessarily result in increased immunogenicity for all vaccines tested; however, optimization of the Andes virus (ANDV) DNA vaccine protected vaccinated hamsters from lethal disease. This is the first time active vaccination with an ANDV DNA vaccine has shown protective efficacy in the hamster model. The adaptation of a human intradermal jet injection device for use as a method of subcutaneous and intramuscular jet injection of DNA vaccines will advance the development of nucleic acid based medical countermeasures for diseases modeled in hamsters.
In patients with wounds admitted to Emergency Departments (ED) acquiring tetanus vaccination history by interview is very unreliable. Protected patients may receive unnecessary prophylaxis and ...unprotected nothing. Aim of the study was to evaluate tetanus immunity status comparing the traditional anamnestic method with the Tetanus Quick Stick (TQS), a rapid immunochromatographic test.
A double-blind prospective study was carried out in the ED of the 1,000 bed teaching hospital Umberto I in Rome. Adult patients (≥18) with wounds attending at the ED were randomly included. Tetanus immunity status was evaluated by healthcare workers (HCWs) comparing the TQS test with the anamnesis. TQS test was performed by a trained HCW and afterwards the anamnesis about tetanus immunity status was collected by another HCW unaware of the TQS result. Also cost analysis was carried out.
Overall 400 patients (242 males and 158 females) were included, mean age was 46.7 ± 20.2 years (median 44 range 18 - 109), 304 (76.0%) were italians and 96 foreigners (24.0%). Overall, 209 (52.2%) resulted TQS +, and protective immunity level was associated to lower mean age (40.1 ± 16.8 vs 53.8 ± 21,1; p<0,01). Using the anamnestic method 336 (84.0%) patients resulted "unprotected", 52 (13.0%) "partially unprotected" and 12 (3.0%) "completely protected". TQS test results showed that 154 (45.8%) out of 336 "unprotected" and 45 (86.5%) out of 52 "partially unprotected" actually had a protective antibody level. Finally two (16.7%) out of 12 "completely protected" group presented a non protective antibody level. Following only the anamnestic method 201 (50.0%) patients would have received some inappropriate treatment. Adopting TQS test in all patients would also be cost-effective saving € 1.95/patient. As tetanus immunity is inversely related to age, for <51 years old patients unnecessary treatment would have been avoided in 57.1% of patients, with a mean reduction per patient of € 7.50/patient with the TQS vs. € 12.69/patient without.
The study showed that tetanus protective immunity prevalence among adult patients attending our ED is about 50% and is mainly influenced by class age. TQS use allowed to reduce drastically inappropriate tetanus vaccine and immunoglobulins booster treatment. Also TQS use reduced costs.
The Bologna Stone, a mineral that became luminescent after chymical treatment, represents one of several "chymical exotica" eagerly sought by natural philosophers of the seventeenth century. ...Curiously, by mid-century the way to make it luminescent was considered a "lost secret" even though several methods had been repeatedly published. This disconnect between published recipes and experimental failures was explained in part by the investigations of Wilhelm Homberg (1653-1715), later the leading chymist of the Académie Royale des Sciences, and in part by the present author's modern reproduction of Homberg's process. This paper describes both endeavours, and explores the often-overlooked difficulties presented by even "trivial" materials involved in experimentation, and how practical reproduction of historical processes (including visits to important locales) can provide a deeper and more vivid understanding of texts as part of our project to better understand the past. It concludes by reflecting on the importance of maintaining a balance between the material and the intellectual when writing the history of chemistry.
George Starkey—chymistry tutor to Robert Boyle, author of immensely popular alchemical treatises, and probably early America's most important scientist—reveals in these pages the daily laboratory ...experimentation of a seventeenth-century alchemist. The editors present in this volume transcriptions of Starkey's texts, their translations, and valuable commentary for the modern reader. Dispelling the myth that alchemy was an irrational enterprise, this remarkable collection of laboratory notebooks and correspondence reveals the otherwise hidden methodologies of one of the seventeenth century's most influential alchemists.
Improving Student Success in Calculus at Seattle University Carter, J. D.; Helliwell, D.; Henrich, Allison ...
PRIMUS : problems, resources, and issues in mathematics undergraduate studies,
02/2016, Letnik:
26, Številka:
2
Journal Article
Recenzirano
Finding ways to improve student success in calculus is a critically important step on the path to supporting students who are pursuing degrees in STEM fields. Far too many students fail calculus 1 ...and are pushed to drop their majors in technical fields. One way of addressing this issue is by following a program that was pioneered at University of Colorado Boulder. At Boulder, oral exam reviews are offered to mathematics students in conjunction with other support. Oral reviews are structured, ungraded, optional, collaborative review sessions that prepare students to take exams by improving their understanding of mathematical concepts. In this paper, we discuss how we have implemented the University of Colorado Boulder model at Seattle University, and we report on the successes and the challenges of the program.
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