44 research outputs found

    The Experience of Pregnancy Discovery andAcceptance: A Descriptive Study Based on freeHierarchical Evocation by Associative Networks

    Get PDF
    Women’s childbearing experiences vary with pregnancy intentional nature and outcome. An Associative Network study targeted 129 women pregnant >1 year ago and their experiences at pregnancy start and post-pregnancy. Word-associations formed 15 themes and 5 metathemes. The main pregnancy discovery themes were “Affect” (39%), “Relationships with others” (11%), and “Logistics” (7%). The main post-pregnancy themes were “Affect” (18%), “Relationship with the child” (13%), and “Personal progress” (12%). The overall polarity index was higher in intended vs. unintended pregnancies. Whatever pregnancy outcome, women expressed impressions of constructive experience. Discovering pregnancy and deciding about it led anyway to personal and social progress

    ssDNA degradation along capillary electrophoresis process using a Tris buffer

    Get PDF
    Tris-Acetate buffer is currently used in the selection and the characterization of ssDNA by capillary electrophoresis (CE). By applying high voltage, the migration of ionic species into the capillary generates a current that induces water electrolysis. This phenomenon is followed by the modification of the pH and the production of Tris derivatives. By injecting ten times by capillary electrophoresis ssDNA (50 nM), the whole oligonucleotide was degraded. In this paper, we will show that the Tris buffer in the running vials is modified along the electrophoretic process by electrochemical reactions. We also observed that the composition of the metal ions changes in the running buffer vials. This phenomenon, never described in CE, is important for fluorescent ssDNA analysis using Tris buffer. The oligonucleotides are degraded by electrochemically synthesized species (present in the running Tris vials) until it disappears, even if the separation buffer in the capillary is clean. To address these issues, we propose to use a sodium phosphate buffer that we demonstrate to be electrochemically inactive

    α,ÎČ-D-Constrained Nucleic Acids Are Strong Terminators of Thermostable DNA Polymerases in Polymerase Chain Reaction

    Get PDF
    (SC5â€Č, RP) α,ÎČ-D- Constrained Nucleic Acids (CNA) are dinucleotide building blocks that can feature either B-type torsional angle values or non-canonical values, depending on their 5â€ČC and P absolute stereochemistry. These CNA are modified neither on the nucleobase nor on the sugar structure and therefore represent a new class of nucleotide with specific chemical and structural characteristics. They promote marked bending in a single stranded DNA so as to preorganize it into a loop-like structure, and they have been shown to induce rigidity within oligonucleotides. Following their synthesis, studies performed on CNA have only focused on the constraints that this family of nucleotides introduced into DNA. On the assumption that bending in a DNA template may produce a terminator structure, we investigated whether CNA could be used as a new strong terminator of polymerization in PCR. We therefore assessed the efficiency of CNA as a terminator in PCR, using triethylene glycol phosphate units as a control. Analyses were performed by denaturing gel electrophoresis and several PCR products were further analysed by sequencing. The results showed that the incorporation of only one CNA was always skipped by the polymerases tested. On the other hand, two CNA units always stopped proofreading polymerases, such as Pfu DNA polymerase, as expected for a strong replication terminator. Non-proofreading enzymes, e.g. Taq DNA polymerase, did not recognize this modification as a strong terminator although it was predominantly stopped by this structure. In conclusion, this first functional use of CNA units shows that these modified nucleotides can be used as novel polymerization terminators of proofreading polymerases. Furthermore, our results lead us to propose that CNA and their derivatives could be useful tools for investigating the behaviour of different classes of polymerases

    Relationship between haemagglutination-inhibiting antibody titres and clinical protection against influenza: development and application of a bayesian random-effects model

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Antibodies directed against haemagglutinin, measured by the haemagglutination inhibition (HI) assay are essential to protective immunity against influenza infection. An HI titre of 1:40 is generally accepted to correspond to a 50% reduction in the risk of contracting influenza in a susceptible population, but limited attempts have been made to further quantify the association between HI titre and protective efficacy.</p> <p>Methods</p> <p>We present a model, using a meta-analytical approach, that estimates the level of clinical protection against influenza at any HI titre level. Source data were derived from a systematic literature review that identified 15 studies, representing a total of 5899 adult subjects and 1304 influenza cases with interval-censored information on HI titre. The parameters of the relationship between HI titre and clinical protection were estimated using Bayesian inference with a consideration of random effects and censorship in the available information.</p> <p>Results</p> <p>A significant and positive relationship between HI titre and clinical protection against influenza was observed in all tested models. This relationship was found to be similar irrespective of the type of viral strain (A or B) and the vaccination status of the individuals.</p> <p>Conclusion</p> <p>Although limitations in the data used should not be overlooked, the relationship derived in this analysis provides a means to predict the efficacy of inactivated influenza vaccines when only immunogenicity data are available. This relationship can also be useful for comparing the efficacy of different influenza vaccines based on their immunological profile.</p

    Incidence and determinants of new AIDS-defining illnesses after HAART initiation in a Senegalese cohort

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Although a dramatic decrease in AIDS progression has been observed after Highly Active Anti Retroviral Therapy (HAART) in both low- and high-resource settings, few data support that fact in low-resource settings.</p> <p>This study describes the incidence of AIDS-defining illnesses (ADI) after HAART initiation and analyzes their risk factors in a low-resource setting. A focus was put on CD4 cell counts and viral load measurements.</p> <p>Methods</p> <p>404 HIV-1-infected Senegalese adult patients were enrolled in a prospective observational cohort and data censored as of April 2008. A Poisson regression was used to model the incidence of ADIs over two periods and to assess its association with baseline variables, current CD4, current viral load, CD4 response, and virological response.</p> <p>Results</p> <p>ADI incidence declined from 20.5 ADIs per 100 person-years, 95% CI = [16.3;25.8] during the first year to 4.3, 95% CI = [2.3;8.1] during the fourth year but increased afterwards. Before 42 months, the decrease was greater in patients with clinical stage CDC-C at baseline and with a viral load remaining below 1000 cp/mL but was uniform across CD4 strata (p = 0.1). After 42 months, 293 patients were still at risk. The current CD4 and viral load were associated with ADI incidence (decrease of 21% per 50 CD4/mm<sup>3 </sup>and of 61% for patients with a viral load < 1000 cp/mL).</p> <p>Conclusions</p> <p>During the first four years, a uniform decline of ADI incidence was observed even in patients with low CD4-cell counts at HAART initiation as long as the viral load remained undetectable. An increase was noted later in patients with immunologic and virological failures but also in patients with only virological failure.</p

    Artefact-free trends in breast cancer incidence over two decades in a whole French DĂ©partement.

    No full text
    International audienceThe objective was to discuss the evolution of the real incidence of breast cancer. Observed incidence as calculated by cancer registries differs from the real incidence because of the artifacts brought by diagnostic procedures and case collection. Age-period-cohort models were applied to nearly 11,200 incident breast cancers collected by the Cancer Registry of Is? from 1983 to 2002 in women aged 30-84. We took into account prior knowledge and assumptions concerning the evolution of real incidence, diagnostic procedures, and collection of cases. In the age group 30-49, no real incidence increase was seen if we assume that diagnostic procedures and collection of cases were not impaired. In women aged 50-69, an increase of real incidence and intensive screening could explain the increase of observed incidence but exact quantifications are difficult. At most, the increase due to screening would reach 50%. In women aged 70-84, no real incidence increase was suspected if we assume that changes in clinical practices and screening led to more breast cancer cases collected
    corecore