The impulsivity rating scale (IRS): preliminary results

Until now, the instruments for the clinical evaluation of impulsivity have relied essentially on either personality inventories or to a lesser extent on specific questionnaires. Therefore this paper presents the preliminary results of a new rating scale: the Impulsivity Rating Scale (IRS). This is a 7-item hetero-evaluation of impulsivity based on the behaviour of the patient in usual life situations. The administration of the scale is easy and short: 15 minutes. The IRS was tested in five different population samples: 31 impulsive inpatients, 36 adults with major depressive episode, 15 healthy control subjects, 56 smokers before and after one week of tobacco withdrawal, and 47 adolescent depressed inpatients before and four weeks after antidepressant treatment. The results show good construct validity, good concurrent validity, good inter-rater reliability and sensitivity to change. A threshold of 8 for the total score (range 0 to 21) gives good specificity and sensitivity. The principal component analysis shows the existence of a main factor composed of all items, with lower correlation for two items which may belong to a second factor needing further investigations.

Acoustical characterisation and monitoring of microbubble clouds

Argon microbubbles will exist in the primary sodium of the next generation of sodium-cooled fast reactors (SFR). Due to its opacity, acoustic methods will be used for the in-service inspection in these reactors, but the presence of such bubbles will greatly affect ultrasonic wave propagation. Moreover, these bubbles can lead to the formation of gas pockets in the reactor and impact cavitation and boiling phenomena. It is therefore necessary to characterise what is called the 'microbubble cloud' by providing the volume fraction and the bubble size distribution. Safety requirements in this field call for robust inspection methods based on very few assumptions about the bubble populations. The objective of this study is to assess the performance of spectroscopic methods in the presence of bubbles with high polydispersity and to monitor an evolving cloud of microbubbles. The histogram and void fractions were estimated according to the regularised inversion of the complex wave number's integral equation. To reduce the need for prior information on the bubble cloud, a specific procedure was used to estimate the maximum radius of the population. The results are presented on the basis of the experimental data obtained and then compared with optical measurements.

Bubbly flow velocity measurement in multiple scattering regime

We propose a technique to measure the velocity of a bubble cloud based on the coda correlation. The method is founded on successive recordings of multiple scattered waves from a bubble cloud. Our model predicts the dependence between the correlation coefficient of these coda waves and the velocity of the bubble cloud under diffusion approximation. The Acoustic experiments are validated by simultaneous optical measurements in a water tank, with a good agreement between the acoustical and the optical methods (relative difference smaller than 7%). This technique can be transposed to any particle flow velocity problems involving multiple scattering effects in acoustics.

Nonlinear ultrasound parameter to monitor cell death in cancer cell samples

A scaling subtraction method was proposed to analyze the radio frequency data from cancer cell samples exposed to an anti-cancer drug and to estimate a nonlinear parameter. The nonlinear parameter was found to be well correlated (R²= 0.62) to the percentage of dead cells in apoptosis and necrosis. The origin of the nonlinearity may be related to a change in contacts between cells, since the nonlinear parameter was well correlated to the average total coordination number of binary packings (R²≥ 0.77). These results suggest that the scaling subtraction method may be used to early quantify chemotherapeutic treatment efficiency.

Assessment of elastic coefficients of child cortical bone using resonant ultrasound spectroscopy

The assessment of the anisotropic elastic properties of non-pathological child cortical bone remains a challenge for the biomechanical engineering community and an important clinical issue. Resonant ultrasound spectroscopy (RUS) can be used to determine bone stiffness coefficients from the mechanical resonances of bone specimens. Here, a RUS protocol was used on 7 fibula specimens from children (mean age 14 ± 3 years) to estimate the whole elastic stiffness tensor of non-pathological child cortical bone considered as orthotropic. Despite a small number of sample, results are consistent with this hypothesis, even if a trend towards transverse isotropy is discussed. Indeed, the average values of the 9 independent stiffness coefficients obtained in this study for child bone are: C₁₁ = 16.73 ± 0.19 GPa, C₂₂ = 16.19 ± 0.12 GPa, C₃₃ = 24.47 ± 0.30 GPa, C₄₄ = 4.14 ± 0.08 GPa, C₅₅ = 4.16 ± 0.07 GPa, C₆₆ = 3.13 ± 0.05 GPa, C₁₂ = 10.14 ± 0.20 GPa, C₁₃ = 10.67 ± 0.27 GPa, C₂₃ = 10.25 ± 0.14 GPa.

Three-dimensional modeling and numerical predictions of multimodal nonlinear behavior in damaged concrete blocks

In this paper, the multimodal nonlinear elastic behavior of concrete, which is representative of a consolidated granular material, is modeled numerically. Starting from a local three-dimensional softening law, the initial stiffness properties are re-estimated according to the local strain field. The experiments deal with samples of thermally damaged concrete blocks successively excited around their first three modes of vibration. The geometry of these samples cannot be described by a one-dimensional approximation in these experiments where compressional and shear motions are strongly coupled. Despite this added complexity, the nonlinear behavior for the three modes of vibration of the samples is well captured by the simulations using a single scalar nonlinear parameter appropriately integrated into the elasticity equations. It is shown that without sufficient attention paid to the latter, the conclusions would have brought erroneous statements such as nonlinearity dispersion or strain type dependence.

Arthroscopically assisted reduction of acute acromioclavicular joint dislocation using a single double-button device: Medium-term clinical and radiological outcomes

INTRODUCTION

Double-button devices for endoscopic management of acute acromioclavicular joint dislocation (ACJD) provide satisfactory short-term functional and radiological results. However, little exists in the literature regarding the long- and medium-term results of these implants, especially regarding the evolution of the acromioclavicular joint (ACJ).

HYPOTHESIS

Satisfactory and steady long- and medium-term outcomes can be achieved in patients with acute ACJD undergoing endoscopically assisted ACJ repair using a single double-button device.

MATERIAL AND METHOD

A retrospective single-center study was conducted in patients with acute Rockwood III and IV ACJD treated endoscopically with a single double-button device from October 2008 to October 2010, allowing a minimum 5-year follow-up. Functional evaluation used Constant and Quick-DASH scores. Clinical evidence of dislocation recurrence was combined with bilateral Zanca views to assess coracoclavicular distance. Acromioclavicular osteoarthritis was evaluated on the Paxinos test and Zanca views.

RESULTS

Nineteen of the 25 operated patients were seen at a mean 76.9±8.5 months' follow-up. Mean age was 34.4±8.3 years. Mean Constant and Quick-DASH scores were 96.2±5.1 and 0.9±1.6 points, respectively. Four patients had a recurrence of their initial dislocation, 3 of whom had positive Paxinos test, whereas the 15 patients without recurrence had a negative test (p=0.004). Five patients had radiological evidence of ACJ osteoarthritis: all 4 patients with recurrence and 1 without (p=0.001).

CONCLUSION

Long- and medium-term radioclinical outcome of endoscopically assisted management of acute ACJD using a single double-button device seems to be satisfactory and steady over time. Recurrence of the initial dislocation appears to be related to onset of degenerative ACJ arthropathy.

LEVEL OF EVIDENCE

Therapeutic type IV-Retrospective case series.

From local to global measurements of nonclassical nonlinear elastic effects in geomaterials

In this letter, the equivalence between local and global measures of nonclassical nonlinear elasticity is established in a slender resonant bar. Nonlinear effects are first measured globally using nonlinear resonance ultrasound spectroscopy (NRUS), which monitors the relative shift of the resonance frequency as a function of the maximum dynamic strain in the sample. Subsequently, nonlinear effects are measured locally at various positions along the sample using dynamic acousto elasticity testing (DAET). After correcting analytically the DAET data for three-dimensional strain effects and integrating numerically these corrected data along the length of the sample, the NRUS global measures are retrieved almost exactly.

Dynamic acousto-elastic test using continuous probe wave and transient vibration to investigate material nonlinearity

This study demonstrates the feasibility of the dynamic acousto-elastic effect of a continuous high frequency wave for investigating the material nonlinearity upon transient vibration. The approach is demonstrated on a concrete sample measuring 15×15×60cm(3). Two ultrasonic transducers (emitter and receiver) are placed at its middle span. A continuous high frequency wave of 500kHz propagates through the material and is modulated with a hammer blow. The position of the hammer blow on the sample is configured to promote the first bending mode of vibration. The use of a continuous wave allows discrete time extraction of the nonlinear behavior by a short-time Fourier transform approach, through the simultaneous comparison of a reference non-modulated signal and an impact-modulated signal. The hammer blow results in phase shifts and variations of signal amplitude between reference and perturbed signals, which are driven by the resonant frequency of the sample. Finally, a comprehensive analysis of the relaxation mechanisms (modulus and attenuation recovery) is conducted to untangle the coupled fast and slow hysteretic effects.

Clinical severity and molecular characteristics of circulating and emerging rotaviruses in young children attending hospital emergency departments in France

Group A rotavirus (RVA) is the leading cause of acute gastroenteritis in young children worldwide. A prospective surveillance network has been set up to investigate the virological and clinical features of RVA infections and to detect the emergence of potentially epidemic strains in France. From 2009 to 2014, RVA-positive stool samples were collected from 4800 children <5 years old attending the paediatric emergency units of 16 large hospitals. Rotaviruses were then genotyped by RT-PCR with regard to their outer capsid proteins VP4 and VP7. Genotyping of 4708 RVA showed that G1P[8] strains (62.2%) were predominant. The incidence of G9P[8] (11.5%), G3P[8] (10.4%) and G2P[4] (6.6%) strains varied considerably, whereas G4P[8] (2.7%) strains were circulating mostly locally. Of note, G12P[8] (1.6%) strains emerged during the seasons 2011-12 and 2012-13 with 4.1% and 3.0% prevalence, respectively. Overall, 40 possible zoonotic reassortants, such as G6 (33.3%) and G8 (15.4%) strains, were detected, and were mostly associated with P[6] (67.5%). Analysis of clinical records of 624 hospitalized children and severity scores from 282 of them showed no difference in clinical manifestations or severity in relation to the genotype. The relative stability of RVA genotypes currently co-circulating and the large predominance of P[8] type strains may ensure vaccine effectiveness in France. The surveillance will continue to monitor the emergence of new reassortants that might not respond to current vaccines, all the more so as all genotypes can cause severe infections in infants.

Decoupling Nonclassical Nonlinear Behavior of Elastic Wave Types

In this Letter, the tensorial nature of the nonequilibrium dynamics in nonlinear mesoscopic elastic materials is evidenced via multimode resonance experiments. In these experiments the dynamic response, including the spatial variations of velocities and strains, is carefully monitored while the sample is vibrated in a purely longitudinal or a purely torsional mode. By analogy with the fact that such experiments can decouple the elements of the linear elastic tensor, we demonstrate that the parameters quantifying the nonequilibrium dynamics of the material differ substantially for a compressional wave and for a shear wave. This result could lead to further understanding of the nonlinear mechanical phenomena that arise in natural systems as well as to the design and engineering of nonlinear acoustic metamaterials.

Identification of a duplicated V3 domain in NS5A associated with cirrhosis and hepatocellular carcinoma in HCV-1b patients

BACKGROUND

The NS5A protein of the hepatitis C virus has been shown to be involved in the development of hepatocellular carcinoma.

OBJECTIVES

In a French multicenter study, we investigated the clinical and epidemiological features of a new HCV genotype 1b strain bearing a wide insertion into the V3 domain.

STUDY DESIGN

We studied NS5A gene sequences in 821 French patients infected with genotype 1b HCV.

RESULTS

We identified an uncharacterized V3 insertion without ORF disruption in 3.05% of the HCV sequences. The insertion comprised 31 amino-acids for the majority of patients; 3 patients had 27 amino-acids insertions and 1 had a 12 amino-acids insertion. Sequence identity between the 31 amino-acids insertions and the V3 domain ranged from 48 to 96% with E-values above 4e(-5), thus illustrating sequence homology and a partial gene duplication event that to our knowledge has never been reported in HCV. Moreover we showed the presence of the duplication at the time of infection and its persistence at least during 12 years in the entire quasispecies. No association was found with extrahepatic diseases. Conversely, patients with cirrhosis were two times more likely to have HCV with this genetic characteristic (p=0.04). Moreover, its prevalence increased with liver disease severity (from 3.0% in patients without cirrhosis to 9.4% in patients with both cirrhosis and HCC, p for trend=0.045).

CONCLUSIONS

We identified a duplicated V3 domain in the HCV-1b NS5A protein for the first time. The duplication may be associated with unfavorable evolution of liver disease including a possible involvement in liver carcinogenesis.

Microbubble dynamics monitoring using a dual modulation method

An experimental method for characterizing microbubbles' oscillations is presented. With a Dual Frequency ultrasound excitation method, both relative and absolute microbubble size variations can be measured. Using the same experimental setup, a simple signal processing step applied to both the amplitude and the frequency modulations yields a two-fold picture of microbubbles' dynamics. In addition, assuming the occurrence of small radial oscillations, the equilibrium radius of the microbubbles can be accurately estimated.

Quantitative linear and nonlinear resonance inspection techniques and analysis for material characterization: application to concrete thermal damage

Developed in the late 1980s, Nonlinear Resonant Ultrasound Spectroscopy (NRUS) has been widely employed in the field of material characterization. Most of the studies assume the measured amplitude to be proportional to the strain amplitude which drives nonlinear phenomena. In 1D resonant bar experiments, the configuration for which NRUS was initially developed, this assumption holds. However, it is not true for samples of general shape which exhibit several resonance mode shapes. This paper proposes a methodology based on linear resonant ultrasound spectroscopy, numerical simulations and nonlinear resonant ultrasound spectroscopy to provide quantitative values of nonlinear elastic moduli taking into account the 3D nature of the samples. In the context of license renewal in the field of nuclear energy, this study aims at providing some quantitative information related to the degree of micro-cracking of concrete and cement based materials in the presence of thermal damage. The resonance based method is validated as regard with concrete microstructure evolution during thermal exposure.

Interest of human papillomavirus DNA quantification and genotyping in paired cervical and urine samples to detect cervical lesions

BACKGROUND

Cervical cancer is caused by persistent infection with high-risk human papillomavirus (HR-HPV). Conventional human papillomavirus (HPV) testing requires cervical sampling. However, vaginal and urine self-sampling methods are more acceptable for patients and result in increased participation when they are available in screening programs. In this context, we have developed a non-invasive screening method via the detection of HPV DNA in urine samples.

PURPOSE

To compare HPV viral loads and genotypes in paired cervical and urine samples, and to assess correlation between virological and cytological results in women seeking gynecological consultation.

METHODS

Paired urine and cervical specimens were collected and analyzed from 230 of 245 women participating in the previously described prospective PapU study. HPV DNA detection and quantification were performed using a real-time PCR method with short fragment PCR primers. Genotyping was carried out using the INNO-LiPA HPV genotyping assay.

RESULTS

The prevalence of HPV in the 230 paired urine and cervical smear samples was 42 and 49 %, respectively. Overall agreement for HPV positivity and negativity between the paired samples was 90 % (κ = 0.80). High HPV viral load in both cervical and urine samples was associated with cytological abnormalities. HPV-positive women were mostly infected with HR-HPV types. The agreement between high- and low-risk HPV (LR-HPV) detection in both samples was 97 % (κ = 0.95 for HR-HPV and κ = 0.97 for LR-HPV).

CONCLUSIONS

High concordance rates for HPV-DNA quantification and high/low-risk HPV genotyping in paired urine/cervical samples suggest that urinary HPV DNA testing could be useful for cervical lesion screening.

Attitudes and expectations of patients with neuromuscular diseases about their participation in a clinical trial

AIM

This study aimed to gain a better understanding of the psychological impact of participating in a clinical trial for patients with Pompe disease (Acid Maltase Deficiency). Attitudes and expectations of adult patients with neuromuscular diseases regarding medical trials are as yet unreported. In order to learn about the psychological consequences of participating in a clinical trial, we conducted a prospective assessment of patients with late-onset Pompe Disease, a rare genetic condition, for which no treatment had been available before. This psychological study was carried out as an ancillary study to the randomized double-blind placebo-controlled trial described elsewhere (van der Ploeg et al., 2010).

SUBJECTS AND METHODS

We assessed patients (n=8) at inclusion, and at 12 and 18 months for six psychological dimensions: depression (Beck Depression Inventory, BDI), hopelessness (Beck Hopelessness Scale, BHS), anxiety (STAI A-B), quality of life (Whoqol-26), social adjustment (S.A.S-self-report) and locus of control (IPC Levenson). We produced a self-administered questionnaire in order to assess the attitudes, motivations and expectations of patients during the trial.

RESULTS

At 12 months, mean social adjustment (SAS-SR, P=0.02) had improved, and at 18 months mean depression score had improved as well (BDI, P=0.03). The quality of life of patients (Whoqol-26) remained unchanged. Throughout the study, patients were more likely to have an internal locus of control than an external one (IPC Levenson). The self-administered questionnaire showed that patients' expectations were disproportionate compared to the medical information they had received starting the trial. For all patients, the first motivation for being enrolled in a clinical trial was "to help research", for half of them the motivation was to "improve their health". Whether patients believed to be part of one group or another (placebo or treatment) depended on their subjective perception of improvement during the trial.

CONCLUSION

Given the small sample size, the conclusions of this study are preliminary. However, findings do suggest that there is a positive psychological impact of participating in a treatment trial. Moreover, the patients' reactions upon unblinding have led us to recommend that patients be asked whether they would like their group assignation disclosed to them or not.

Applying diffuse ultrasound under dynamic loading to improve closed crack characterization in concrete

Recent studies show the ability of diffuse ultrasound to characterize surface breaking cracks in concrete. However, derived parameters are sensitive to the presence of partially opened zones along the crack whose pattern may differ from one sample to another. The aim of this letter is to study the variation of diffuse ultrasound parameters while the sample is driven by a low frequency bending load which alternatively opens and closes the crack, allowing to access supplementary information about its morphology. The results show the sensitivity of the method for various crack depths and highlight its potential for concrete nondestructive evaluation.

Inter-rater reliability of two depression rating scales, MADRS and DRRS, based on videotape records of structured interviews

The inter-rater reliability of the French versions of the MADRS and the DRRS was studied on the basis of 58 videotape records of structured standardised interviews of depressed inpatients under antidepressant treatment. Each patient was assessed by two trained raters, from the same videotape recording. The inter-rater reliability of total scores was high with both scales (intra-class correlation coefficients: 0.86 for MADRS and 0.77 for DRRS). However, the inter-rater reliability for individual items was higher and more homogeneous for the MADRS than for the DRRS. Finally, the structured interview in French appears to be relevant for the MADRS, but it should be improved for the DRRS.

[Soft tissue infection associated with bacteremia caused by Shewanella putrefaciens]

Shewanella putrefaciens is rarely involved in human infectious disease. We report here a case of soft tissue infection with bacteremia on a patient with risk factors (liver cirrhosis, diabetes mellitus).

Microbubble cloud characterization by nonlinear frequency mixing

In the frame of the fourth generation forum, France decided to develop sodium fast nuclear reactors. French Safety Authority requests the associated monitoring of argon gas into sodium. This implies to estimate the void fraction, and a histogram indicating the bubble population. In this context, the present letter studies the possibility of achieving an accurate determination of the histogram with acoustic methods. A nonlinear, two-frequency mixing technique has been implemented, and a specific optical device has been developed in order to validate the experimental results. The acoustically reconstructed histograms are in excellent agreement with those obtained using optical methods.

[Epidemiology of healthcare-associated infections due to MRSA in Brest University Hospital from 2004 to 2007. Impact of hydroalcoholic gel and antibiotics consumptions]

The fight against healthcare-associated infections is based on preventive measures of multidrug resistant bacteria diffusion. Hand hygiene is the simplest and the most effective preventive measure to reduce cross-transmission of infectious agents. Hydroalcoholic solutions for hand hygiene was recently introduced in the University Hospital of Brest (France). The aims of the study were: to describe the epidemiology of healthcare-associated infections due to methicillin-resistant Staphylococcus aureus (MRSA); to determine the annual consumptions of antistaphylococcal antibiotics; and to discuss the relation between consumption of antiseptic products or antibiotics and the epidemiology of MRSA.

METHODS

A retrospective epidemiological and pharmaco-epidemiological study was realized from January 2004 to December 2007 in the University Hospital of Brest (France). It allowed to bring to light the cases of healthcare-associated infections due to MRSA and to quantify the consumptions of hang hygiene products and antistaphylococcal antibiotics.

RESULTS

this retrospective study showed a decrease of healthcare-associated infections due to MRSA and an increase of the consumption of hydroalcoholic solutions. Antistaphylococcal resistance rates also decreased in a context of fall of the global antibiotics consumption in the hospital.

Non-O1, non-O139 Vibrio cholerae bacteraemia in a cirrhotic patient

Vibrio cholerae serogroups O1 or O139 are the aetiological agents of cholera. The pathogenicity of non-O1, non-O139 V. cholerae is less well known. These worldwide bacteria are responsible for gastrointestinal infections or, more rarely, bacteraemia in patients with an underlying disease, leading to life-threatening complications. We report a case of non-O1, non-O139 V. cholerae bacteraemia due to a haemolytic strain in a cirrhotic patient. Early antibiotherapy allowed a good outcome. The aim of this case report is to underline the virulence of non-choleragenic Vibrio strains, possibly linked to haemolysin production, and the potential danger of consuming undercooked seafood or exposing wounds to sea water in cirrhotic patients.

Effect of the presence and size of a localized nonlinear source in concrete

The aim of the present letter is to identify the contribution of a macroscopic source of elastic nonlinearity in concrete, a medium which by nature is nonlinear, and belongs to the nonlinear mesoscopic class of materials. The influence of real, localized macro-cracks is characterized with respect to the intrinsic nonlinearity of the material. The influence of the size of the source on the amplitude of the measured nonlinearity is qualitatively demonstrated. A comparison is made between the changes in linear and nonlinear parameters.

Differentiating Emery-Dreifuss muscular dystrophy and collagen VI-related myopathies using a specific CT scanner pattern

Bethlem myopathy and Ullrich congenital muscular dystrophy are part of the heterogeneous group of collagen VI-related muscle disorders. They are caused by mutations in collagen VI (ColVI) genes (COL6A1, COL6A2, and COL6A3) while LMNA mutations cause autosomal dominant Emery-Dreifuss muscular dystrophy. A muscular dystrophy pattern and contractures are found in all three conditions, making differential diagnosis difficult especially in young patients when cardiomyopathy is absent. We retrospectively assessed upper and lower limb muscle CT scans in 14 Bethlem/Ullrich patients and 13 Emery-Dreifuss patients with identified mutations. CT was able to differentiate Emery-Dreifuss muscular dystrophy from ColVI-related myopathies in selected thigh muscles and to a lesser extent calves muscles: rectus femoris fatty infiltration was selectively present in Bethlem/Ullrich patients while posterior thigh muscles infiltration was more prominently found in Emery-Dreifuss patients. A more severe fatty infiltration particularly in the leg posterior compartment was found in the Emery-Dreifuss group.

Fatal congenital tuberculosis due to a Beijing strain in a premature neonate

Congenital tuberculosis (TB) remains a rare disease but is fatal if untreated. Early detection is difficult because of the non-specific nature of the symptoms in TB during pregnancy and infancy. This report summarizes a case of congenital TB in a very premature infant, born at 25 weeks gestation. Miliary TB was diagnosed in the mother when the neonate was 20 days old. Antituberculous therapy allowed a rapid improvement in the mother. The infant died at 27 days old. A Beijing genotype strain of Mycobacterium tuberculosis was isolated both in the mother, from pulmonary and urine specimens, and in the infant, from peritoneal fluid.

[Ventricular dysfunction during acute fever in Dakar, Senegal. Clinical data and serological studies]

During a study, the authors observed clinical and ultrasound evidence of "ventricular dysfunction during acute fever" due to ue to "severe acute myocarditis" supports therapeutic management since 4/8 patients in this study were infected either by Chlamydia (CT and especially CP) or by Mycoplasma pneumoniae, that are both sensitive to antimicrobial therapy using macrolides. Five of 8 patients presented coinfection with 2 and even 3 infectious agents (CP-enterovirus-adenovirus).

Materno-fetal transmission of human coronaviruses: a prospective pilot study

This prospective pilot study investigates the possibility of materno-fetal transmission of human coronaviruses (HCoV) responsible for cases of neonatal infection. This vertical transmission was studied with 159 samples from mother-child couples: maternal vaginal (MV) and respiratory (MR) samples during labor; and newborn gastric sample (NG) with detection of HCoV (229E, OC-43, NL-63, HKU1) via real time RT PCR. HCoV was detected in 12 samples (229E: 11; HKU1: 1) from seven mother-child couples. For three couples, only MR tested positive (cases 1–3). For two other couples all three samples (MV, MR and NG) tested positive (cases 4 and 5). For case 6, only MV and NG tested positive. In case 7, only MV was positive. Possible vertical transmission of HCoV was hypothesized in this pilot study and requires further investigation on a larger scale.

[Vertical transmission of human coronavirus. Prospective pilot study]

Les coronavirus humains (HCoV) ont été impliqués dans la survenue d'infections respiratoires nosocomiales chez les nouveau-nés. Plusieurs cas d'infections néonatales ont été mis en évidence. Cette étude pilote recherche l'existence d'une éventuelle transmission maternofœtale des HCoV pouvant expliquer les cas infections néonatales observées dans les premières 24 heures de vie.

Matériel et méthode

Étude monocentrique prospective pilote. Étude des couples mère–enfant par la réalisation de trois prélèvements : vaginal et respiratoire chez la mère (VM et RM) lors du travail, gastrique chez le nouveau-né (GNN). Suivi clinique des nouveau-nés et des mères jusqu'à j3. Analyse virologique des échantillons par reverse transcription-polymerase chain reaction (RT-PCR) en temps réel pour la recherche des HCoV 229-E et OC43.

Résultats

Cent cinquante-neuf couples mère–enfant ont été inclus de juillet 2003 à août 2005. Seul HCoV 229-E a été détecté dans 11 échantillons chez six couples mère–enfant. Pour deux couples, les trois prélèvements (VM, RM et GNN) étaient positifs (cas 1 et 2). Pour le cas 3, seuls le VM et GNN étaient positifs. Pour deux couples, seuls les RM étaient positifs (cas 4 et 5). Pour le cas 6, seul le VM était positif. Pour les trois GNN positifs, aucun enfant n'était symptomatique.

Conclusion

Une possible transmission verticale des HCoV est mise en évidence dans cette étude pilote qui nécessite désormais d'être poursuivie à plus large échelle. Il convient également d'inclure la recherche des coronavirus humains identifiés récemment, HCoV NL63 et HKU1, et d'analyser le profil génomique des HCoV détectés chez les trois couples mère–enfant positifs.

Genetic diversity of the hepatitis C virus: Impact and issues in the antiviral therapy

The hepatitis C Virus (HCV) presents a high degree of genetic variability which is explained by the combination of a lack of proof reading by the RNA dependant RNA polymerase and a high level of viral replication. The resulting genetic polymorphism defines a classification in clades, genotypes, subtypes, isolates and quasispecies. This diversity is known to reflect the range of responses to Interferon therapy. The genotype is one of the predictive parameters currently used to define the antiviral treatment strategy and the chance of therapeutic success. Studies have also reported the potential impact of the viral genetic polymorphism in the outcome of antiviral therapy in patients infected by the same HCV genotype. Both structural and non structural genomic regions of HCV have been suggested to be involved in the Interferon pathway and the resistance to antiviral therapy. In this review, we first detail the viral basis of HCV diversity. Then, the HCV genetic regions that may be implicated in resistance to therapy are described, with a focus on the structural region encoded by the E2 gene and the non-structural genes NS3, NS5A and NS5B. Both mechanisms of the Interferon resistance and of the new antiviral drugs are described in this review.