[Hepatitis E virus: Blood transfusion implications]. / Virus de l'hépatite E, implications en transfusion sanguine.

Hepatitis E virus (HEV) is a non-enveloped RNA virus transmitted by the fecal-oral route. Autochthonous hepatitis E occurring in developed countries is caused by genotypes 3 and 4 and is a zoonotic infection. Humans are infected mostly after ingestion of undercooked meat from infected animals. Most HEV 3 and 4 infections are clinically inapparent. However, genotype 3 (HEV 3) can lead to chronic hepatitis in immuno-compromised patients such as organ-transplant recipients and patients with haematological malignancies. In Europe, HEV 3 is implicated in transfusion-transmitted HEV infection. In France, as observed in several European countries, prevalence of HEV RNA and specific IgG antibodies are high indicating that viral circulation is important. The systematic HEV NAT screening of blood donations used for preparation of solvent detergent plasma indicate that 1 to 2218 donation is infected by HEV RNA. The need or implementation's impacts of safety measures to prevent HEV transmission by blood transfusion are under reflexion by French's health authorities. The HEV NAT screening is the only available tool of prevention. Alternative strategies are under investigation including individual or mini pool NAT testing all or part of blood donations.

[Urinary incontinence in nulliparous women: prevalence and evaluation of self-perineal reeducation]. / Incontinence urinaire chez la femme nullipare: prévalence et évaluation de l'auto-rééducation périnéale.

AIMS: To assess the prevalence of urinary incontinence (UI) in a population of young nulliparous women and the effectiveness of self-perineal exercises in symptomatic women. MATERIAL: Three hundred and fifteen nulliparous students from French secondary establishments answered through a secure website, created for the study, an anonymous questionnaire about UI. The questionnaire included validated symptom scores (International Consultation on Incontinence Questionnaire-Short Form, ICIQ-UI SF) and quality of life (Contilife). Women who reported UI were asked to perform a self-perineal rehabilitation program for 8 weeks. A second questionnaire was completed after reeducation to assess the evolution of their UI. RESULTS: Among the 315 respondents, 92 women (29.2%) reported UI. The mean age was 23.0 (± 4.4) years in the continent group and 22.9 (± 3.6) years in the incontinent group. Only 24 of the 92 women with UI (26.1%) completed the reeducation program with a significant improvement in UI and quality of life (QoL). CONCLUSION: UI is a common disorder in young nulliparous women. Perineal self-exercises without the intervention of a professional could help to improve the disorders. LEVEL OF EVIDENCE: 5.

[Chagas disease and blood transfusion: an emerging issue in non-endemic countries]. / Maladie de Chagas et transfusion sanguine: un problème parasitaire émergent dans les pays non endémiques.

Chagas disease or American human trypanosomiasis, is a parasitic disease due to Trypanosoma cruzi, which is endemic in Latin America. The parasite is transmitted by haematophagous vectors from reduviidae family. In some patients, the parasite is responsible for severe complications such as cardiac manifestations, gastrointestinal involvement and neurologic disease. Imported Chagas disease by immigration in non-endemic countries poses the threat of the infection transmission by blood transfusion. In order to prevent this risk, the French Blood Services (EFS) introduced systematic screening of at-risk blood donors for anti-T. cruzi antibodies, in May 2007. The concerned donors are people originating from an endemic area, donors with mothers originating from such an area and individuals who had lived in or travelled to endemic areas. Donors were screened with two different Elisas simultaneously: one Elisa using purified parasite lysate antigens and the second one composed of recombinant antigens. Positive results and discrepant results were further assayed with an immunofluorescence assay. A seroprevalence assay was performed in the 17 French blood centres after an 18-month testing period from May 2007 to December 2008. During this period 4,637,479 million donations were collected. Out of these 163,740 donations were tested (3.5%). The prevalence of anti-T. cruzi antibodies was one in 32,800 donations. Five positive donors were identified. All of them were originating from endemic areas. A rate of 0.85% indeterminate results was found. Screening strategy revision was decided to reduce the number of donors unnecessarily deferred.

[Chagas disease screening in the blood donor population]. / Dépistage de la maladie de Chagas chez les donneurs de sang.

In May 2007, the French Blood Service (Etablissement français du sang, EFS) introduced systematic screening of at-risk blood donors for anti-Trypanosoma cruzi antibodies. This concerned donors originating from an endemic area, donors with mothers originating from such an area and individuals who had lived in or travelled to endemic areas, whatever the length of their stay. Five samples out of 163,740 were positive, all from individuals originating from an endemic area. One thousand three hundred seventy-four blood donations were considered as equivocal because they had discordant results on the two Elisa tests used in screening. The authors discuss difficulties presented by routine screening of travellers and residents as well as the advantages and drawbacks of the strategy used. They present arguments in favour of its simplification.

Overview of revised measures to prevent malaria transmission by blood transfusion in France.

Plasmodial transmission by blood donation is rare in non-endemic countries, but a very serious complication of blood transfusion. The French national blood service (Etablissement Français du Sang and Centre de Transfusion sanguine des Armees) intended to revise the measures to strengthen blood safety with regard to Plasmodiae as transmissible pathogens. To limit the risk of transmission during infusion, serious additive measures have been taken for more than a decade in France, which is the European country with the highest rate of exposure to imported plasmodial infections or malaria. These measures were revised and strengthened after the occurrence of a lethal transfusion-transmitted infection in 2002, but did not prevent another occurrence in 2006. This report examines the weaknesses of the systems and aims at emphasizing the safety measures already taken and addresses issues to best respond to that risk.

Multicentric evaluation of the DiaMed enzyme-linked immunosorbent assay malaria antibody test for screening of blood donors for malaria.

BACKGROUND: The risk of malaria transmission by blood transfusion is critical due to extensive travel from endemic areas to non-endemic areas. An enzyme-linked immunosorbent assay (ELISA) malaria antibody test has been developed that is claimed to perform better than the immunofluorescence assay test (IFAT). The assay contains antigens to both Plasmodium falciparum and Plasmodium vivax. A multicentre study was performed to evaluate the appropriateness of replacing the IFAT by the new ELISA test. MATERIAL AND METHODS: Nine French blood banks participated in this multicentre study. Two panels of samples were evaluated. The first included 4163 samples from healthy donors and was used to calculate clinical specificity of the assay. The second involved 10,995 samples, either collected retrospectively or prospectively from malaria-risk donors , was used to assess the comparative performance of the ELISA and IFAT. Discordant samples were further tested using an in-house IFAT and also tested for presence of Plasmodium DNA by polymerase chain reaction. RESULTS: The ELISA showed a clinical specificity of 99.02%. In the malaria-risk blood donors groups, the retrospective group showed a concordance rate of 92.6% (k = 0.90), while the prospective group showed a concordance rate of 97% (k = 0.46). After confirming the discordant sample results by an in-house IFAT, the k index increased to 0.81. None of the discordant samples was shown to contain Plasmodium DNA. CONCLUSION: The performance of the ELISA test in this study has confirmed its potential as a new screening test for use in blood banks, as an alternative to the IFAT in prevention of transfusion-transmitted malaria in non-endemic countries.

Chagas disease screening in the French blood donorpopulation. Screening assays and donor selection

Debido al incremento de la prevalencia de la enfermedad de Chagas en la Guayana Francesa, las autoridades sanitarias decidieron interrumpir la donación de sangre en este territorio e implementar un cribaje para Tripanosomacruzi en los donantes con riesgo de padecer la enfermedad. La evaluación de diferentes pruebas serológicas permitió la selección dedos pruebas de ELISA, que se usarán simultáneamente como cribaje de rutina en los bancos de sangre. Una de las pruebas se basa en antígenos recombinantes y la segunda en antígenos crudos. En caso de discrepancia o como prueba de confirmación si los dos ELISA son positivos, se utilizará un método de inmunofluorescencia. El cribaje se realizará en donantes de sangre de riesgo: personas nacidas en o de madre nacida en zona endémica y donantes que han viajado a América Latina independientemente de la duración de su estancia (AU)

The identification of an increase in the prevalence of Chagas disease in the French Guiana led the French health authorities to the decision of halting blood collection in this French overseas territory and implementing Trypanosomacruzi screening in the French at risk blood donors. Subsequently, an evaluation of the performances of different serological assays allowed the selection of 2 different ELISAs which will be used simultaneously in routine blood screening. One of the ELISA is based on recombinant antigens and the other one on crude antigens. An Immunofluorescence assay will be used as a confirmatory test in case of positivity of the 2 ELISAs or in case of discrepancy between the 2 screening assays. Screening will be performed in at risk donors: people born in or from mother born in an endemic area and donors traveling to Southern America, regardless the stay length (AU)

[Application of molecular biology to blood transfusion safety: the nucleic acid testing]. / Application de la biologie moléculaire à la sécurité virale transfusionnelle: le dépistage génomique viral.

Nucleic Acid Testing (NAT) for HIV-1 and HCV has been introduced in France and became mandatory for all homologous blood donations since July 1st 2001 in addition to serology screening. Previously, a feasibility study led to the selection of 2 technologies : a TMA based assay (Chiron) uses the Procleix HIV-/HCV assay on pools of 8 samples and a PCR based assay from BioMérieux-Roche which is a combination of an RNA extraction system (NucliSens, BioMérieux) with a fully automated system for nucleic acid amplification and detection (Cobas Amplicor, Roche). This system uses the Cobas Ampliscreen HCV test v.2.0 and the The Cobas Ampliscreen HIV test v1.5, on 24 sample pools. Pooling was required because single-donation testing is not yet feasible, as a result of the limitations in automation available for all current NAT technologies. The two technologies were easily implemented and showed nearly the same detection limit for HCV RNA and HIV-1 RNA. During a one-year period, from July 1st 2001 to June 30, 2002, out of the 2.5 million donations tested, the NAT yield resulted in one HIV-1 RNA positive-antibody negative donation and one HCV RNA positive-antibody negative donation. Two HIV NAT positive-antibody negative donations were missed by minipool NAT because a very low viral load. Moreover, the NAT implementation did not impact on blood component availability, including platelet concentrates.

[Comparison of two techniques for detection of anti-Plasmodium falciparum antibodies: Falciparum-spot IF (Biomérieux) and Malaria IgG Celisa (BMD). Preliminary results]. / Comparaison de deux techniques de détection des anticorps anti-Plasmodium falciparum: Falciparum-spot IF (Biomérieux) et Malaria IgG Celisa (BMD). Résultats préliminaires.

We compared a new Elisa assay to detect malaria antibodies: Malaria IgG Celisa (BMD) with the IFAT technique Falciparum-spot IF (Biomérieux): sensitivity, specificity, predictive positive and negative values were 81%, 99%, 95%, 95%, respectively. Eight patients had positive thick blood smear out of 23 performed. For these eight confirmed acute malaria cases, the Elisa assay was negative in five instances. For two recent malaria attacks both Elisa and IFI were negative. With blood donors, two sera were IFAT positive and Elisa negative; 16 were IFAT doubtful and Elisa negative. Doubtful results rose up to 13.5% by IFAT against 1.5% by Elisa assay. We preferred kappa coefficient instead of chi 2 test for data analysis, which measures the concordance degree between the two techniques. Here concordance is moderate. Choosing an Elisa assay to detect the transmission of malaria for at-risk blood donors collides with the method sensitivity compared with IFAT as reference.

[125I]BQ3020, a novel endothelin agonist selective for the endothelinB receptor subtype.

The endothelins represent a family of three (ET-1, ET-2, and ET-3) isopeptides that are derived from vascular endothelial cells and function as potent vasoconstrictors. Two endothelin receptor subtypes, ETA and ETB, have been cloned and are structurally similar to the large family of guanine nucleotide-binding protein (G-protein) linked receptors. The ET receptor subtypes can also be distinguished by their different pharmacological profiles.. A novel linear peptide fragment of endothelin-1 (ET-1), N-acetyl-[Ala11,15]ET-1[6-21] (BQ3020) has been identified as a potent and ETB-selective agonist. [125I]BQ3020 binds with high affinity (Kd = 31 pM) and limited capacity (Bmax = 570 fmol/mg protein) to a single class of recognition sites in rat cerebellum. High affinity [125I]BQ3020 binding is reduced in the presence of guanine nucleotides indicating an interaction with high and low affinity states of the ETB receptor. This protocol describes the use of [125I]BQ3020 as a specific radioligand for the ETB receptor.

[Trophoblastic interferons and embryonal immune tolerance]. / Les interférons trophoblastiques et la tolérance immunologique embryonnaire.

Current evidence support the hypothesis that trophoblast interferons play a key role in preventing maternal immunologal rejection of the embryonic semi-allograft. The information of this review is divided in two sections. In the first section we described molecular and biological characteristics of type I (alpha, beta, omega, tau and spl) and type II (gamma) interferons. In the second section we emphasize studies on immunoendocrine functions of IFN-tau (oTP-1 or trophoblastins) in the network of cytokines and hormonal environment at the uterine embryonic interface.

Pharmacological characterization of the rat cerebellar endothelin B (ETB) receptor using the novel agonist radioligand [125I]BQ3020.

A novel linear peptide fragment of endothelin-1 (ET-1), N-acetyl-[Ala11,15]ET-1[6-21] (BQ3020) has been identified as a potent and ETB-selective agonist. The present studies were conducted in order to characterize the binding of [125I]BQ3020 to the ETB receptor in rat cerebellum. [125I]BQ3020 (0.1 nM) bound with high specificity (90% of total binding) and selectivity for the ETB receptor. ET-1, ET-2, and ET-3 inhibited 0.1 nM [125I]BQ3020 binding with equivalent affinity (Ki values = 55-110 pM). The sarafotoxins S6a, S6b, and S6c also potently inhibited [125I]BQ3020 binding (Ki values = 55-2000 pM). The ETA-selective antagonist, BQ123 (100 microM) did not significantly inhibit [125I]BQ3020 binding. Ligand saturation studies indicated that [125I]BQ3020 labeled a single class of recognition sites with very high affinity (Kd = 31 pM) and limited capacity (Bmax = 570 fmol/mg protein). High affinity 0.1 nM [125I]BQ3020 binding was reduced by 40-50% in the presence of 1 mM guanine nucleotides. Additional competition studies indicated that ET-1 and ET-2 produced biphasic inhibition curves in competing for 0.5 nM [125I]BQ3020. The high affinity component of the ET-1 inhibition curve was subsequently eliminated in the presence of 1 mM GTP-gamma-S The guanine nucleotide sensitivity of [125I]BQ3020 binding offers the possibility that different functional consequences of ETB receptor activation may be mediated by multiple affinity states of the receptor. The present data demonstrate that [125I]BQ3020 is a potent and selective agonist for the ETB receptor that can discriminate high and low affinity states of the ETB receptor.

Characterization of the bisphosphonate recognition site on hydroxyapatite using radioligand binding techniques with [14C]citric acid.

The present studies characterize the binding of [14C]citric acid to synthetic hydroxyapatite (HA) crystals. [14C]Citric acid specifically bound to HA and was dependent upon the concentration of HA in the assay. The binding of [14C] citric acid to HA reached equilibrium within 20 min and remained stable for at least 90 min. Dissociation of bound [14C]citric acid was biphasic in nature since both rapid and more slowly reversible binding components were detected. Saturation experiments also indicated that [14C]citric acid labeled two recognition sites with different affinity (KdH = 42 nM and KdL = 24,000 nM) and density (BmaxH = 161 fmol/micrograms HA and BmaxL = 8.8 pmol/micrograms HA). Ligand competition experiments revealed that compounds that are known to readily bind bone (e.g., sodium pyrophosphate, methylene diphosphonic acid, etidronate) potently inhibited the binding of [14C]citric acid to HA, whereas compounds known to have poorer affinity for bone (e.g., oxalic acid and GABA) did not. Computer analysis of these inhibition curves revealed specific ligand interactions at two different affinity recognition sites. The present results indicate that [14C]citric acid binds discrete sites on synthetic HA in a fashion consistent with a specific labeling of the bisphosphonate recognition site. Analysis of the binding of [14C]citric acid to HA provides a useful method to further explore the structure activity relationships of novel compounds that have binding affinity for bone.

Acid-base status of mink blood during storage.

The changes in pH, pCO2, pO2, BE, and SBC during storage of anaerobic drawn arterial blood for 24 hours at different temperatures were measured (Table Ia, Ib) and illustrated (Fig. 1). Correction tables (Table III) for determination of the initial acid-base data are constructed based upon the regression equations in Table II. The changes in the acid-base values of mink blood are much higher than in equine, porcine, and canine blood during storage at 21-24 degrees C and 0-4 degrees C for 24 hours.