Résultats de trois méthodes pour la détection de la mutation précore G1896A du virus de l’hépatite B chez les donneurs de sang français : PCR temps réel, séquençage et test Inno-LIPA

AIM: To screen hepatitis B virus (HBV) genotypes and associated basal core promoter (BCP; T1762A/A1764) and precore (PC; A1896) mutations among the 100 HBV surface antigen (HBsAg) positive voluntary blood donors in France. METHODS: HBV genotypes were determined by using direct sequence analysis. Three methods were used to detect G1896A mutation: non-commercial real-time PCR (PCRTR°, line probe assay (InnoLiPA HBV PreCore, INNOGENETICS(®)) and direct sequencing of precore gene. HBV viral load was quantified with two commercial real-time PCR (COBAS(®) AmpliPrep/COBAS(®) TaqMan(®) HBV Test/Roche and Real Time HBV/M2000/Abbott). RESULTS: The mean age of donors was 30 (18-64). Patients were from Africa (42%), Europa (50%), and Asia (8%). HBV/D was the most predominant (37%) genotype followed by HBV/A (31%) and HBV/E (22%). PC and BCP mutants were found in 57% with Inno-LIPA HBV test and 59% with both PCRTR and sequencing methods. A significant difference in the viral load of blood donors with wild and PC mutants was observed with the Taqman Cobas real time PCR (3,19 Log(10) UI/ml versus 4,93 Log(10) UI/ml, p < 0.05). Precore phenotype determination was in agreement with the three PC mutation detection methods in 56% of cases. CONCLUSIONS: Non-Caucasian genotype E was present in the French blood donors. PC mutation was more common than BCP mutations in this study. As HBV infected blood donors were more often asymptomatic carriers, we could speculate that the G1896A mutation may favour the asymptomatic state, supporting previous observations

False-Positive Human Immunodeficiency Virus Enzyme Immunoassay Results in Pregnant Women

Objective: Examine whether false-positive HIV enzyme immunoassay (EIA) test results occur more frequently among pregnant women than among women who are not pregnant and men (others). Design: To obtain a large number of pregnant women and others tested for HIV, we identified specimens tested at a national laboratory using Genetic Systems HIV-1/HIV-2 Plus O EIA from July 2007 to June 2008. Methods: Specimens with EIA repeatedly reactive and Western blot-negative or indeterminate results were considered EIA false-positive. We compared the false-positive rate among uninfected pregnant women and others, adjusting for HIV prevalence. Among all reactive EIAs, we evaluated the proportion of false-positives, positive predictive value (PPV), and Western blot bands among indeterminates, by pregnancy status. Results: HIV prevalence was 0.06 % among 921,438 pregnant women and 1.34 % among 1,103,961 others. The false-positive rate was lower for pregnant women than others (0.14 % vs. 0.21%, odds ratio 0.65 [95 % confidence interval 0.61, 0.70]). Pregnant women with reactive EIAs were more likely than others (p,0.01) to have Western blot-negative (52.9 % vs. 9.8%) and indeterminate results (17.0 % vs. 3.7%) and lower PPV (30 % vs. 87%). The p24 band was detected more often among pregnant women (p,0.01). Conclusions: False-positive HIV EIA results were rare and occurred less frequently among pregnant women than others

Multiple thromboembolism with multiple causes in a 69-year-old woman: a case report

<p>Abstract</p> <p>Introduction</p> <p>Aggressive, recurrent embolisms require accurate etiologic diagnosis. We describe the case of a 69-year-old Italian Caucasian woman with recurrent arterial embolisms in whom several sources and triggers of thrombosis were detected.</p> <p>Case presentation</p> <p>The patient, a 69-year-old Italian Caucasian woman, presented with a systemic embolism that was initially attributed to atrial fibrillation. The recurrence of embolisms despite anti-thrombotic therapy prompted a re-evaluation of the clinical presentation. New potential causes of thrombosis emerged in this patient, including thrombocytosis associated with the <it>JAK2 V617F </it>mutation and the very rare mural thrombosis of the descending aorta. A mural thrombus in the pulmonary artery was detected contiguous with the aortic mural thrombosis, raising the possibility of a clinically silent ductus Botalli as the initiating event. The patient was treated with warfarin, aspirin, hydroxyurea, and surgery.</p> <p>Conclusions</p> <p>The diagnosis was achieved via systematic use of imaging procedures and reconsideration of blood tests performed to explore the diagnosis of thrombosis. This allowed a deeper and more detailed analysis of the case beyond the conventional approach, which would have aimed to identify one cause for the condition at hand, in this case, atrial fibrillation. The broader approach that we used resulted in the diagnosis of multiple embolisms from multiple sites and multiple causes.</p

A revised method for estimating hepatitis B virus transfusion residual risk based on antibody to hepatitis B core antigen incident cases

BACKGROUND: To take into account the transient nature of hepatitis B virus (HBV) antigenemia, the calculation of HBV residual risk (RR), based on the incidence/window period model, is adjusted by a correction factor that adds uncertainty to the RR estimates. STUDY DESIGN AND METHODS: This new method to estimate the RR for HBV is a weighted sum of the RR derived from hepatitis B surface antigen (HBsAg) incident cases and the one derived from antibody hepatitis B core antigen (HBc) incident cases. An anti-HBc incident case was defined as a donation from a blood donor who had made at least one anti-HBc–negative donation followed by a donation that was found positive with two different assays within a 3-year period and positive for at least one of the following markers: 1) antibody to hepatitis B e antigen or hepatitis B e antigen, 2) anti-HBc immunoglobulin M, 3) HBV DNA, 4) hepatitis B surface antibody without HBV vaccination history, or 5) HBV DNA retrospectively found in the previous donation. Five overlapping 3-year study periods between 2000 and 2006 were analyzed. RESULTS: The HBV RR estimated with the classical method ranged from 1.51 (2000-2002) to 0.69 per million donations in 2004 through 2006 with a decrease in 2002 through 2004 due to only two HBsAg incident cases reported in this period. By applying the revised model, the HBV RR ranged from 1.06 (2000-2002) to 0.49 per million donations (2004-2006), with a regular decrease. CONCLUSION: The new presented model provides HBV RR estimates that do not statistically differ from those obtained with the classical model; however, it provides more accurate data, especially in low endemic areas where the HBsAg incidence is low

Harnessing difference: a capability-based framework for stakeholder engagement in environmental innovation

Innovation for environmental sustainability requires firms to engage with external stakeholders to access expertise, solve complex problems, and gain social legitimacy. In this open innovation context, stakeholder engagement is construed as a dynamic capability that can harness differences between external stakeholders to augment their respective resource bases. An integrative systematic review of evidence from 88 scientific articles finds that engaging stakeholders in environmental innovation requires three distinct levels of capability: specific operational capabilities; first-order dynamic capabilities to manage the engagement (engagement management capabilities); and second-order dynamic capabilities to make use of contrasting ways of seeing the world to reframe problems, combine competencies in new ways, and co-create innovative solutions (value framing), and to learn from stakeholder engagement activities (systematized learning). These findings enhance understanding of how firms can effectively incorporate stakeholder perspectives for environmental innovation, and provide an organizing framework for further research into open innovation and co-creation more broadly. Wider contributions to the dynamic capabilities literature are to (i) offer a departure point for further research into the relationship between first-order and second-order dynamic capabilities, (ii) suggest that institutional theory can help explain the dynamic capability of value framing, (iii) build on evidence that inter-institutional learning is contingent on not only the similarity but also the differences between organizational value frames, and (iv) suggest that operating capabilities impact the effectiveness of dynamic capabilities, rather than only the other way around, as is usually assumed. A methodological contribution is made through the application of quality assessment criteria scores and intercoder reliability statistics to the selection of articles included in the systematic review

Harnessing difference: a capability-based framework for stakeholder engagement in environmental innovation

Innovation for environmental sustainability requires firms to engage with external stakeholders to access expertise, solve complex problems, and gain social legitimacy. In this open innovation context, stakeholder engagement is construed as a dynamic capability that can harness differences between external stakeholders to augment their respective resource bases. An integrative systematic review of evidence from 88 scientific articles finds that engaging stakeholders in environmental innovation requires three distinct levels of capability: specific operational capabilities; first-order dynamic capabilities to manage the engagement (engagement management capabilities); and second-order dynamic capabilities to make use of contrasting ways of seeing the world to reframe problems, combine competencies in new ways, and co-create innovative solutions (value framing), and to learn from stakeholder engagement activities (systematized learning). These findings enhance understanding of how firms can effectively incorporate stakeholder perspectives for environmental innovation, and provide an organizing framework for further research into open innovation and co-creation more broadly. Wider contributions to the dynamic capabilities literature are to (i) offer a departure point for further research into the relationship between first-order and second-order dynamic capabilities, (ii) suggest that institutional theory can help explain the dynamic capability of value framing, (iii) build on evidence that inter-institutional learning is contingent on not only the similarity but also the differences between organizational value frames, and (iv) suggest that operating capabilities impact the effectiveness of dynamic capabilities, rather than only the other way around, as is usually assumed. A methodological contribution is made through the application of quality assessment criteria scores and intercoder reliability statistics to the selection of articles included in the systematic review

QTLs for oil yield components in an elite oil palm (Elaeis guineensis) cross

Increased modern farming of superior types of the oil palm, Elaeis guineensis Jacq., which has naturally efficient oil biosynthesis, has made it the world’s foremost edible oil crop. Breeding improvement is, however, circumscribed by time and costs associated with the tree’s long reproductive cycle, large size and 10–15 years of field testing. Marker-assisted breeding has considerable potential for improving this crop. Towards this, quantitative trait loci (QTL) linked to oil yield component traits were mapped in a high-yield population. In total, 164 QTLs associated with 21 oil yield component traits were discovered, with cumulative QTL effects increasing in tandem with the number of QTL markers and matching the QT+ alleles for each trait. The QTLs confirmed all traits to be polygenic, with many genes of individual small effects on independent loci, but epistatic interactions are not ruled out. Furthermore, several QTLs maybe pleiotropic as suggested by QTL clustering of inter-related traits on almost all linkage groups. Certain regions of the chromosomes seem richer in the genes affecting a particular yield component trait and likely encompass pleiotropic, epistatic and heterotic effects. A large proportion of the identified additive effects from QTLs may actually arise from genic interactions between loci. Comparisons with previous mapping studies show that most of the QTLs were for similar traits and shared similar marker intervals on the same linkage groups. Practical applications for such QTLs in marker-assisted breeding will require seeking them out in different genetic backgrounds and environments

Diffraction techniques and vibrational spectroscopy opportunities to characterise bones

From a histological point of view, bones that allow body mobility and protection of internal organs consist not only of different organic and inorganic tissues but include vascular and nervous elements as well. Moreover, due to its ability to host different ions and cations, its mineral part represents an important reservoir, playing a key role in the metabolic activity of the organism. From a structural point of view, bones can be considered as a composite material displaying a hierarchical structure at different scales. At the nanometre scale, an organic part, i.e. collagen fibrils and an inorganic part, i.e. calcium phosphate nanocrystals are intimately mixed to assure particular mechanical properties

Transfusion-transmitted infections

Although the risk of transfusion-transmitted infections today is lower than ever, the supply of safe blood products remains subject to contamination with known and yet to be identified human pathogens. Only continuous improvement and implementation of donor selection, sensitive screening tests and effective inactivation procedures can ensure the elimination, or at least reduction, of the risk of acquiring transfusion transmitted infections. In addition, ongoing education and up-to-date information regarding infectious agents that are potentially transmitted via blood components is necessary to promote the reporting of adverse events, an important component of transfusion transmitted disease surveillance. Thus, the collaboration of all parties involved in transfusion medicine, including national haemovigilance systems, is crucial for protecting a secure blood product supply from known and emerging blood-borne pathogens