447 research outputs found
Agronomie Oasienne. Projet de Coopération Franco-Tunisien. Proposition d'un projet de Coopération technique : "Recherches pour le Développement de l'agriculture d'oasis dans le Sud Tunisien". Rapport de missions Synthèse et propositions
Ce document est le résultat des missions réalisées au cours du premier semestre 1991 dans le cadre du projet d'appui à la recherche sur l'agriculture d'oasis en Tunisie. Il regroupe deux dossiers : - Rapports de missions et - Synthèses et propositions. Dans la première partie du document, après une brève présentation du projet, 4 volets sont détaillés : - "Inventaire du patrimoine génétique Oasien", - "Protection des cultures", "Agronomie et Développement", et "Technologie post-récolte". La deuxième partie du rapport présente les moyens, la programmation ainsi que le suivi et évaluation du proje
Real 3D-packaging: a breakthrough for high power electronics for automotive applications
Power electronics stands at the crossroad of highly convoluted disciplines of physics: thermal science, mechanics and electronics. In order to respond to the growing and demanding automotive market, designers have no choice but to assemble off-the-shelf parts, keeping the onus of managing themselves thermal losses and stray inductances at interfaces. Power mechatronics is the buzz word for this. It has for long envisioned double-sided cooling and wire-bondless interconnections as ways to go. Merging those impediments and opportunities into a global solution, aPSI3D has developed an integrated approach for multi-physical co-design with its customers, offering both plug-in cooled power modules and maximum value transfer to the inverter. Eventually, a 50 power module with imbedded cold plate size reduction for a 100kW inverter is obtained vs. state-of-the art pin fin standard products. With a 10nH stray inductance, this solution is paving the way to more than 100A wide bandgap semiconductor die based highly efficient power modules
Genome-wide diversity and gene expression profiling of Babesia microti isolates identify polymorphic genes that mediate host-pathogen interactions
Babesia microti, a tick-transmitted, intraerythrocytic protozoan parasite circulating mainly among small mammals, is the primary cause of human babesiosis. While most cases are transmitted by Ixodes ticks, the disease may also be transmitted through blood transfusion and perinatally. A comprehensive analysis of genome composition, genetic diversity, and gene expression profiling of seven B. microti isolates revealed that genetic variation in isolates from the Northeast United States is almost exclusively associated with genes encoding the surface proteome and secretome of the parasite. Furthermore, we found that polymorphism is restricted to a small number of genes, which are highly expressed during infection. In order to identify pathogen-encoded factors involved in host-parasite interactions, we screened a proteome array comprised of 174 B. microti proteins, including several predicted members of the parasite secretome. Using this immuno-proteomic approach we identified several novel antigens that trigger strong host immune responses during the onset of infection. The genomic and immunological data presented herein provide the first insights into the determinants of B. microti interaction with its mammalian hosts and their relevance for understanding the selective pressures acting on parasite evolution
Unintegrated HIV-1 provides an inducible and functional reservoir in untreated and highly active antiretroviral therapy-treated patients
<p>Abstract</p> <p>Background</p> <p>The presence of HIV-1 preintegration reservoir was assessed in an <it>in vitro </it>experimental model of latent HIV-1 infection, and in patients treated or not with highly active antiretroviral therapy (HAART).</p> <p>Results</p> <p>In resting CD4<sup>+ </sup>T lymphocytes latently infected <it>in vitro </it>with HIV-1, we demonstrated that the polyclonal activation induced a HIV-1 replication, which could be prevented by the use of an HIV-1 integrase inhibitor. We also showed that this reservoir was labile since the rescuable HIV-1-antigens production from unintegrated HIV-1 genomes declined over time. These data confirm that our experimental approach allows the characterization of a functional unintegrated HIV-1 reservoir. We then explored the preintegration reservoir in HIV-1-infected patients. This reservoir was detected in 11 of 12 untreated patients, in 4 of 10 sustained responders to HAART, and in one incomplete responder. This reservoir was also inducible, labile, and anti-HIV-1 integrase drug inhibited its induction. Finally, this reservoir was associated with the presence of spontaneous HIV-1 antigens producing CD4<sup>+ </sup>T cells in blood from 3 of 3 untreated patients and 2 of 2 sustained responders to HAART harboring a preintegration reservoir.</p> <p>Conclusion</p> <p>This preintegration phase of HIV-1 latency could be a consequence of the ongoing viral replication in untreated patients and of a residual viral replication in treated patients.</p
Suppression of HIV-1 replication by microRNA effectors
The rate of HIV-1 gene expression is a key step that determines the kinetics of virus spread and AIDS progression. Viral entry and gene expression were described to be the key determinants for cell permissiveness to HIV. Recent reports highlighted the involvement of miRNA in regulating HIV-1 replication post-transcriptionally. In this study we explored the role of cellular factors required for miRNA-mediated mRNA translational inhibition in regulating HIV-1 gene expression. Here we show that HIV-1 mRNAs associate and co-localize with components of the RNA Induced Silencing Complex (RISC), and we characterize some of the proteins required for miRNA-mediated silencing (miRNA effectors). RCK/p54, GW182, LSm-1 and XRN1 negatively regulate HIV-1 gene expression by preventing viral mRNA association with polysomes. Interestingly, knockdown of RCK/p54 or DGCR8 resulted in virus reactivation in PBMCs isolated from HIV infected patients treated with suppressive HAART
Feasibility and efficacy of early lung cancer diagnosis with chest computed tomography in HIV-infected smokers
International audienceOBJECTIVE: Lung cancer screening with chest computed tomography (CT) is beneficial in smokers aged 55 to 74 years. We studied the risks, benefits and feasibility of early lung cancer diagnosis with CT in HIV-infected smokers. DESIGN AND SETTING: French, multicentre, single round chest CT study in France, realized between February 2011 and June 2012. PARTICIPANTS: Patients were HIV-infected smokers at least 40 years, at least 20 pack-years, with a CD4 T-lymphocyte nadir count below 350 cells/μl. INTERVENTION: Single chest CT with a proposed standardized workup algorithm of positive images. MAIN OUTCOME MEASURE: The outcome was the number of histologically proven lung cancers diagnosed by CT with a 2-year follow-up. RESULTS: Median age of the 442 included patients was 49.8 years, 81.6% were under 55 years, 84% were men, median smoking was 30 pack-years, median nadir and last CD4 cell counts were 168 and 574 cells/μl, respectively, and 90% of patients had a plasma HIV RNA below 50 copies/ml. A positive image at baseline was reported in 94 (21%) patients, and 15 (3.4%) patients had 18 invasive procedures with no serious adverse events. Lung cancer was diagnosed in 10 patients (six at early stages), of which nine (2.0%, 95% confidence interval: 0.9-3.8) were CT detected, and eight in patients below 55 years. CONCLUSION: Early lung cancer diagnosis with CT in HIV-infected smokers was feasible, safe, and yielded a significant number of cancers. Lung cancer screening of HIV-infected smokers with an important history of immunodeficiency revealed a substantial number of cancers at younger ages than the targeted range in the general populatio
Dengue Spatial and Temporal Patterns, French Guiana, 2001
To study a 2001 dengue fever outbreak in Iracoubo, French Guiana, we recorded the location of all patients’ homes and the date when symptoms were first observed. A geographic information system was used to integrate the patient-related information. The Knox test, a classic space-time analysis technique, was used to detect spatiotemporal clustering. Analysis of the relative-risk (RR) variations when space and time distances vary, highlighted the maximum space and time extent of a dengue transmission focus. The results show that heterogeneity in the RR variations in space and time corresponds to known entomologic and epidemiologic factors, such as the mosquito feeding cycle and host-seeking behavior. This finding demonstrates the relevance and potential of the use of GIS and spatial statistics for elaborating a dengue fever surveillance strategy
Long-term Immune Response to Hepatitis B Virus Vaccination Regimens in Adults With Human Immunodeficiency Virus 1: Secondary Analysis of a Randomized Clinical Trial.
IMPORTANCE:Data on long-term immune responses to hepatitis B virus (HBV) vaccination in adults with human immunodeficiency virus 1 (HIV-1) infection are scarce.OBJECTIVE:To compare long-term (up to month 42) immune responses to the standard HBV vaccination regimen with a 4-injection intramuscular double-dose regimen and a 4-injection intradermal low-dose regimen.DESIGN, SETTING, AND PARTICIPANTS:The phase 3, open-label, multicenter parallel-group (1:1:1 allocation ratio) randomized clinical trial was conducted from June 28, 2007, to October 23, 2008, at 33 centers in France. Participants included 437 HBV-seronegative adults with HIV-1 and CD4 cell counts of more than 200/μL. Follow-up was extended to September 12, 2012, and data were assessed from February 13, 2015, to January 22, 2016. The analysis was imputed for an intention-to-treat population.INTERVENTIONS:Patients were randomly assigned to receive 3 intramuscular standard-dose (20-μg) injections of recombinant HBV vaccine at weeks 0, 4, and 24 (IM20 × 3 group) (145 participants), 4 intramuscular double-dose (40-μg) injections at weeks 0, 4, 8, and 24 (IM40 × 4 group) (148 participants), or 4 intradermal low-dose (4-μg) injections at weeks 0, 4, 8, and 24 (ID4 × 4 group) (144 participants).MAIN OUTCOMES AND MEASURES:The previously published primary trial end point was the percentage of responders at week 28, defined as patients with hepatitis B surface antibody (HBsAb) levels of at least 10 mIU/mL among patients who received at least 1 vaccine dose. The secondary trial end points included the percentage of responders at months 18, 30, and 42 and the duration of response from week 28. Multiple imputation was used to address missing measurements during the follow-up.RESULTS:Among the 437 patients randomized, 426 received at least 1 dose of vaccine. Of these, 287 were men (67.4%) and they had a mean (SD) age of 42.9 (9.7) years. The percentage of responders at month 42 was 41% (95% CI, 33%-49%) in the IM20 × 3 group, 71% (95% CI, 64%-79%) in the IM40 × 4 group (P < .001 vs the IM20 × 3 group), and 44% (95% CI, 35%-53%) in the ID4 × 4 group (P = .64 vs IM20 × 3 group). Fifteen percent of the patients had HBsAb titers of less than 10 mIU/mL at 33.1 months in the IM40 × 4 group, 8.7 months in the IM20 × 3 group, and 6.8 months in the ID4 × 4 group.CONCLUSIONS AND RELEVANCE:In this follow-up of a trial of adults with HIV-1 infection, the IM40 × 4 regimen of recombinant HBV vaccine improved long-term immune response compared with the standard regimen.TRIAL REGISTRATION:clinicaltrials.gov Identifier: NCT00480792
Efficacy of broccoli and glucoraphanin in COVID-19: From hypothesis to proof-of-concept with three experimental clinical cases
COVID-19 is described in a clinical case involving a patient who proposed the hypothesis that Nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-interacting nutrients may help to prevent severe COVID-19 symptoms. Capsules of broccoli seeds containing glucoraphanin were being taken before the onset of SARS-CoV-2 infection and were continued daily for over a month after the first COVID-19 symptoms. They were found to reduce many of the symptoms rapidly and for a duration of 6-12 h by repeated dosing. When the patient was stable but still suffering from cough and nasal obstruction when not taking the broccoli capsules, a double-blind induced cough challenge confirmed the speed of onset of the capsules (less than 10 min). A second clinical case with lower broccoli doses carried out during the cytokine storm confirmed the clinical benefits already observed. A third clinical case showed similar effects at the onset of symptoms. In the first clinical trial, we used a dose of under 600 mmol per day of glucoraphanin. However, such a high dose may induce pharmacologic effects that require careful examination before the performance of any study. It is likely that the fast onset of action is mediated through the TRPA1 channel. These experimental clinical cases represent a proof-of-concept confirming the hypothesis that Nrf2interacting nutrients are effective in COVID-19. However, this cannot be used in practice before the availability of further safety data, and confirmation is necessary through proper trials on efficacy and safety.Peer reviewe
- …
