301 research outputs found
Single shot temporal measurement of short x-ray pulses using very fast photoconductive detectors
This report gives the status of the development of picosecond photoconductive detectors. The main application of these devices is the single shot temporal measurement of picosecond X-ray, U.V. or visible light pulses. We compare different materials, describe the X-ray autocorrelator and the single shot sampler developed by LETI/SCSI, Grenoble, France
Incidence and Risk Factors of First-Line HAART Discontinuation: Is it Worth Choosing Competing Risk or Standard Survival Approaches?
International audienceObjectives: To estimate the incidences of first-line HAART discontinuation (for intolerance, treatment failure or treatment simplification) and their risk factors by standard survival (1-KM, Cox model) or competing risk approach (CIF, Fine-Gray model) in HIV infected patients. Methods: We studied 1136 patients receiving first-line Highly Active Antiretroviral Therapies (HAART), aged over 18 years, from the Dat'AIDS cohort, Toulouse, France, between January 2000 and June 2008. Cumulative incidence was estimated with 1-KM and CIF estimators and risk factors with Cox and Fine-Gray models. Results: There were 265 discontinuations for intolerance, 136 simplifications, 101 treatment failure and 274 other reasons. One year incidences were 19.0% versus 16.8%, 8.0% versus 6.0%, 6.3% versus 4.8% and 20.0% versus 17.3%, with the estimators 1-KM and CIF, respectively. For intolerance, both models identified similar risk factors. For risk factors of simplification or treatment failure, results differed by the model. Conclusions: As expected, the 1-KM overestimates the incidence of treatment discontinuation. For early and frequent events such as intolerance, the Cox and the Fine-Gray models appear to give similar results. For late and rare events, potentially exposed to competing risk, results differed. The common or specific nature of a factor may also play a role
Task sharing for family planning services, Burkina Faso
© 2019, World Health Organization. All rights reserved. Problem In Burkina Faso, the coverage of services for family planning is low due to shortage of qualified health staff and limited access to services. Approach Following the launch of the Ouagadougou Partnership, an alliance to catalyse the expansion of family planning services, the health ministry created a consortium of family planning stakeholders in 2011. The consortium adopted a collaborative framework to implement a pilot project for task sharing in family planning at community and primary health-care centre levels in two rural districts. Stakeholders were responsible for their areas of expertise. These areas included advocacy; monitoring and evaluation; and capacity development of community health workers (CHWs) to offer oral and injectable contraceptives to new users and of auxiliary nurses and auxiliary midwives to provide implants and intrauterine devices. The health ministry implemented supportive supervision cascades involving relevant planning and service levels. Local setting In Burkina Faso, only 15% (2563/17 087) of married women used modern contraceptives in 2010. Relevant changes Adoption of new policies and clinical care standards expanded task sharing roles in family planning. The consortium trained a total of 79 CHWs and 124 auxiliary nurses and midwives. Between January 2017 and December 2018, CHWs provided injectables to 3698 new users, and auxiliary nurses or midwives provided 726 intrauterine devices and 2574 implants to new users. No safety issues were reported. Lessons learnt The pilot project was feasible and safe, however, financial constraints are hindering scale-up efforts. Supportive supervision cascades were critical in ensuring success
Effectiveness of post-partum family planning interventions on contraceptive use and method mix at 1 year after childbirth in Kinshasa, DR Congo (Yam Daabo): a single-blind, cluster-randomised controlled trial.
BACKGROUND:In rural Burkina Faso, a package of six low-technology, post-partum contraceptive interventions (ie, refresher training for providers, a counselling tool, supportive supervision, daily availability of contraceptive services, client appointment cards, and invitation letters to attend appointments for partners), aimed at strengthening existing primary health-care services and enhancing demand for them, doubled the use of modern contraceptives at 12 months post partum (ie, 55% uptake in intervention recipients vs 29% in routine-care users). This study assessed the effect of a similar package but in urban settings of Kinshasa province, Democratic Republic of the Congo, in an effort to reduce the unmet need for post-partum family planning. METHODS:Yam Daabo was a multi-intervention, single-blinded, cluster-randomised controlled trial done in six primary health-care centres (clusters) in Kinshasa. Centres were randomly allocated to receive the six-component intervention or standard antenatal and postnatal care in matched pairs (1:1) on the basis of number of monthly births, the ratio of health workers per population in the health zone, and the urban and suburban settings. Only data analysts could be masked to cluster allocation. Health-care facilities were eligible if they provided a continuum of antenatal, delivery, and postnatal care, were well stocked with contraceptives, and were situated close to the main study centre. All pregnant women presenting to the six centres were eligible if they were in their third pregnancy trimester and had no counterindications to deliver in the facility. The main outcome was prevalence of use of modern contraceptives at 12 months after delivery. Analysis was by modified intention-to-treat using generalised linear mixed models or Fisher's exact test for small groups. Prevalence ratios were adjusted for cluster effects and baseline characteristics. This study was registered with the Pan-African Clinical Trials Registry (PACTR201609001784334). FINDINGS:From July 1, 2016, to Feb 2, 2017, eight of 52 clinics assessed for eligibility met the criteria and were randomised. Of 690 women approached, 576 (83%) women were enrolled: 286 in the four intervention clusters and 290 in the four control clusters. Of them, 519 (90%) completed the 12-month study exit interview (252 in the intervention group and 267 in the control group) and were included in the intention-to-treat analysis. At 12 months, 115 (46%) of 252 women in the intervention group and 94 (35%) of 267 in the control group were using modern contraceptives (adjusted prevalence ratio [PR] 1·58, 95% CI 0·74-3·38), with significant differences in the use of contraceptive implants (22% vs 6%; adjusted PR 4·36, 95% CI 1·96-9·70), but without difference in the use of short-acting contraceptives (23% vs 28%; 0·92, 0·29-2·98) and non-modern or inappropriate methods (7% vs 18%; 0·45, 0·13-1·54). There were no serious adverse events or maternal deaths related to the study. INTERPRETATION:The Yam Daabo intervention package did not have a significant effect on the overall use of effective modern contraceptives but significantly increased implant use in women post partum who live in urban settings in Kinshasa up to a year after childbirth. However, interferences from external family planning initiatives in the control group might have diminished differences between the services received. Such an intervention could be potentially relevant in similar contexts in DR Congo and other countries. FUNDING:Government of France; UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction
Inheritance of an Epigenetic Mark: The CpG DNA Methyltransferase 1 Is Required for De Novo Establishment of a Complex Pattern of Non-CpG Methylation
Site-specific methylation of cytosines is a key epigenetic mark of vertebrate DNA. While a majority of the methylated residues are in the symmetrical (meC)pG:Gp(meC) configuration, a smaller, but significant fraction is found in the CpA, CpT and CpC asymmetric (non-CpG) dinucleotides. CpG methylation is reproducibly maintained by the activity of the DNA methyltransferase 1 (Dnmt1) on the newly replicated hemimethylated substrates (meC)pG:GpC. On the other hand, establishment and hereditary maintenance of non-CpG methylation patterns have not been analyzed in detail. We previously reported the occurrence of site- and allele-specific methylation at both CpG and non-CpG sites. Here we characterize a hereditary complex of non-CpG methylation, with the transgenerational maintenance of three distinct profiles in a constant ratio, associated with extensive CpG methylation. These observations raised the question of the signal leading to the maintenance of the pattern of asymmetric methylation. The complete non-CpG pattern was reinstated at each generation in spite of the fact that the majority of the sperm genomes contained either none or only one methylated non-CpG site. This observation led us to the hypothesis that the stable CpG patterns might act as blueprints for the maintenance of non-CpG DNA methylation. As predicted, non-CpG DNA methylation profiles were abrogated in a mutant lacking Dnmt1, the enzymes responsible for CpG methylation, but not in mutants defective for either Dnmt3a or Dnmt2
Dnmt2/Trdmt1 as mediator of RNA polymerase II transcriptional activity in cardiac growth
Dnmt2/Trdmt1 is a methyltransferase, which has been shown to methylate tRNAs. Deficient mutants were reported to exhibit various, seemingly unrelated, defects in development and RNA-mediated epigenetic heredity. Here we report a role in a distinct developmental regulation effected by a noncoding RNA. We show that Dnmt2-deficiency in mice results in cardiac hypertrophy. Echocardiographic measurements revealed that cardiac function is preserved notwithstanding the increased dimensions of the organ due to cardiomyocyte enlargement. Mechanistically, activation of the P-TEFb complex, a critical step for cardiac growth, results from increased dissociation of the negatively regulating Rn7sk non-coding RNA component in Dnmt2-deficient cells. Our data suggest that Dnmt2 plays an unexpected role for regulation of cardiac growth by modulating activity of the P-TEFb complex. © 2016 Ghanbarian et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Mitochondrial Reactive Oxygen Species Are Obligatory Signals for Glucose-Induced Insulin Secretion
OBJECTIVE—Insulin secretion involves complex events in which the mitochondria play a pivotal role in the generation of signals that couple glucose detection to insulin secretion. Studies on the mitochondrial generation of reactive oxygen species (ROS) generally focus on chronic nutrient exposure. Here, we investigate whether transient mitochondrial ROS production linked to glucose-induced increased respiration might act as a signal for monitoring insulin secretion
Toxoplasmic encephalitis IRIS in HIV-infected patients: a case series and review of the literature
Assessment of the Food Habits of the Moroccan Dorcas Gazelle in M’Sabih Talaa, West Central Morocco, Using the trnL Approach
Food habits of the Moroccan dorcas gazelle, Gazella dorcas massaesyla, previously investigated in the 1980s using microhistological fecal analysis, in the M’Sabih Talaa Reserve, west central Morocco, were re-evaluated over three seasons (spring, summer and autumn 2009) using the trnL approach to determine the diet composition and its seasonal variation from fecal samples. Taxonomic identification was carried out using the identification originating from the database built from EMBL and the list of plant species within the reserve. The total taxonomic richness in the reserve was 130 instead of 171 species in the 1980s. The diet composition revealed to be much more diversified (71 plant taxa belonging to 57 genus and 29 families) than it was 22 years ago (29 identified taxa). Thirty-four taxa were newly identified in the diet while 13 reported in 1986–87 were not found. Moroccan dorcas gazelle showed a high preference to Acacia gummifera, Anagallis arvensis, Glebionis coronaria, Cladanthus arabicus, Diplotaxis tenuisiliqua, Erodium salzmannii, Limonium thouini, Lotus arenarius and Zizyphus lotus. Seasonal variations occurred in both number (40–41 taxa in spring-summer and 49 taxa in autumn vs. respectively 23–22 and 26 in 1986–1987) and taxonomic type of eaten plant taxa. This dietary diversification could be attributed either to the difference in methods of analysis, trnL approach having a higher taxonomic resolution, or a potential change in nutritional quality of plants over time
- …