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Exploring coagulation in newborns and children is a challenge due to the low levels of both procoagulant factors and inhibitors. Conventional coagulation tests might be inadequate to explore all of these changes. The aim of the study is to evaluate the thrombin generation assay, a global test to explore coagulation, in a pediatric population (n=586) compared to an adult population (n=166). The thrombin generation assays were performed using Calibrated Automated Thrombography with two different tissue factor concentrations (1 and 5 pM), with and without thrombomodulin (TM). In the absence of TM, the endogenous thrombin potential (ETP) is significantly lower in the pediatric population, reflecting the decrease in procoagulant factors. In the presence of TM, ETP values in pediatric subjects are within the reference range of adult values. The thrombin generation assay demonstrates that coagulation balance is maintained in the pediatric population.

Women now live more than a third of their lives after the onset of menopause. The decline in endogenous estrogen production during this period is accompanied by functional disorders that affect quality of life. These symptoms may be relieved by menopausal hormone therapy (MHT) initially based on the administration of equine conjugated estrogens (mainly in the United States, oral route) or the natural estrogen, 17β-estradiol (in Europe, transdermal route). Estrogen receptor α (ERα), but not ERβ, mediates most of the physiological effects of estrogens. ERα belongs to the superfamily of nuclear receptors and regulates the transcription of genes via its activation functions AF1 and AF2. In addition to these classical genomic actions, estrogens can activate a subpopulation of ERα present at the cell membrane and thereby induce rapid signals. In this review, we will summarize the evolution of MHTs in last decades, as well as treatments that use various selective estrogen receptor modulators (SERMs). Next, we will describe recent advances in the understanding of the mechanisms of estrogen action, in particular the respective roles of nuclear and membrane ERα as well as the potential implications for future therapies.

Today, esthetic enhancement is one of the main reasons why patients seek orthodontic treatment. Governed by the canons of beauty dictated by our society, the smile is a key component in this quest for perfect beauty. Hence, the orthodontist is often the first specialist to be consulted by adolescents, but also, more and more, by adults as well. Using simple tools, the practitioner must be able to make a precise analysis of the patient combining both orthodontic and periodontal examinations with an esthetic periodontal diagnosis.Using this analysis, the orthodontist must be able to identify his/her patient's periodontal morphotype and assess whether there is a risk of complications during treatment. One of the main complications that may arise is periodontal recession, which can both impact the esthetic result and give rise to patient anxiety, very soon leaving the orthodontist at a loss. If in doubt, it is essential to refer one's patient to the general dentist or to the periodontist.In this paper, the authors will describe a didactic decision-making tree, which will assist practitioners in learning how to manage their patients.A synergistic approach to global patient management will ensure an optimal outcome by providing the patient with an appropriate and individualized treatment procedure.

Manual blood smear review is required when an anomaly detected by the automated hematologic analyzer triggers a flag. Our will through this study is to optimize these flagging thresholds for manual slide review in order to limit workload, while insuring clinical care through no extra false-negative. Flagging causes of 4,373 samples were investigated by manual slide review, after having been run on ADVIA 2120i. A set of 6 user-adjustments is proposed. By implementing all recommendations that we made, false-positive rate falls from 81.8% to 58.6%, while PPV increases from 18.2% to 23.7%. Hence, use of such optimized thresholds enables us to maximize efficiency without altering clinical care, but each laboratory should establish its own criteria to take into consideration local distinctive features.

Diagnosis of abdominal aortic aneurysm (AAA) at preoperative stage is increasingly frequent. It carries both a local risk of rupture and an increased global cardiovascular risk. Patients with AAA have indeed a 20 times higher risk of dying from myocardial infarction or stroke than from a ruptured aneurysm. Cardiovascular risk factors control is therefore essential, particularly smoking cessation. Treatment in cardiovascular prevention is also warranted. Seeking for atheromatous sites is needed as they determine prognosis. Evidence of the benefit of medical treatment to slow AAA growth is still lacking. In practice, it is recommended to prescribe statins and angiotensin converting enzyme inhibitor to prevent cardiovascular events. These preventive measures are as well necessary to improve postoperative prognosis and must be continued after surgical repair. A vascular medical and surgical cooperation is primordial to enhance comprehensive management of patients with AAA.

The purpose of this article is to describe the setting up of 15 blood gas analyzers GEM(®) Premier™ 4000 (IL) at Montpellier hospital. This experience includes analytical characterization (within and between run coefficient of variation) using GSE and GHE IL controls, correlation of 35 samples with a routinely used laboratory blood gas analyzer (Cobas b221, Roche(®)). We shall also develop the training, the habilitation and its follow-up for the user staff (450 people) of the different hospital's units in the aim of the accreditation.

Neurological soft signs (NSS) include anomalies in motor integration, coordination, sensory integration and lateralization and could be endophenotypic markers in autism spectrum disorders (ASD). Their characterization provides a more precise phenotype of ASD and more homogeneous subtypes to facilitate clinical and genetic research. Few scales for NSS have been adapted and validated in children including children with ASD. Our objective was to perform an adaptation to the child of a scale assessing neurological soft signs and a validation study in both general and clinical populations.We have selected the NSS scale of Krebs et al. (2000) already validated in adults. It encompasses 5 dimensions: motor coordination, motor integration, sensory integration, involuntary movement, laterality. After a preliminary study that examined 42 children, several changes have been made to the original version to adapt it to the child and to increase its feasibility, particularly in children with ASD. Then we conducted a validation study by assessing the psychometric properties of this scale in a population of 86 children including 26 children with ASD (DSM 5 Criteria) and 60 typically developing children. Children's ages ranged between 6 and 12 years, and patients and controls were matched for gender, age and intelligence. Patients were assessed using the Autism diagnostic Interview-revised and the Childhood Autism Rating Scale to confirm diagnosis. Typically developing children were assessed using the semi-structured Mini International Neuropsychiatric Interview for Children and Adolescents to eliminate any psychiatric disorder. All children with neurological pathologies (history of cerebral palsy, congenital anomaly of the central nervous system, epilepsy, tuberous sclerosis, neurofibromatosis, antecedent of severe head trauma) and obvious physical deformities or sensory deficits that could interfere with neurological assessment were excluded from the study. Both patients and controls were assessed using the Raven Progressive Matrices to exclude intellectual disability, and the adapted Krebs' scale for the assessment of NSS.Adaptation of the scale consisted of a modification in the order of items, in the use of concrete supports for the assessment of laterality and in the elimination of item constructive praxis. The internal consistency was good with a Cronbach alpha of 0.87. Inter-rater reliability was good, kappa coefficient was greater than 0.75 for 16 items, 3 items had a kappa value between 0.74 and 0.60, only 1 item had a kappa coefficient between 0.4 and 0.59. Good inter-rater reliability was also checked for the total score with a value of intra-class correlation coefficient (ICC) of 0.91. Principal component analysis found five factors accounting for 62.96 % of the total variance. About the comparison between patients and controls, significant differences were found for NSS total score (P=0.000) and all subscores.The adaptation for children of the Krebs et al.' NSS scale proved to be valid, especially in children with ASD.

Despite being rare cancers, testicular seminoma and non-seminoma play an important role in oncology: they represent a model on how to optimize radiological follow-up, aiming at a lowest possible radiation exposure and secondary cancer risk. Males diagnosed with testicular cancer undergo frequently prolonged follow-up with CT-scans with potential toxic side effects, in particular secondary cancers. To reduce the risks linked to ionizing radiation, precise follow-up protocols have been developed. The number of recommended CT-scanners has been significantly reduced over the last 10 years. The CT scanners have evolved technically and new acquisition protocols have the potential to reduce the radiation exposure further.

Any pharmacological treatment should ideally be effective and safe. The supervision of an ongoing therapy should control that individualized goals are reached while tolerance and safety are present. In case of not reaching the predefined objectives, the causes of failure should first be screened (for instance, exclusion of poor patient compliance), and the treatment should be then optimized: dose adjustment, add-on of another drug (if possible synergistic combination) and/or shift to a more effective pharmacological therapy. In some cases, therapeutic monitoring may be useful or even mandatory in order to better adjust drug dosing and thus guarantee both efficacy and safety.

Circumpapillary retinal nerve fiber layer (cpRNFL) analysis by spectral domain optical coherence tomography (SD-OCT) has become essential for the assessment of glaucoma patients. The foveal projection is conventionally below the disc plane, creating an angle with the horizontal meridian, the disc-fovea angle. The purpose of this study is to evaluate the role of adjustment of cpRNFL analysis based on this angle.This study concerns 40 control eyes and 55 eyes affected with and followed for primary open angle glaucoma (POAG). After precise localization of the optic disc center and the axis connecting it to the center of the fovea, a circular peripapillary scan is performed with Spectralis OCT (Heidelberg Engineering, Germany). The mean thickness in each of six papillary sectors and the global mean thickness of the cpRNFL were evaluated. The ROC (receiver operating characteristic) analysis evaluated the diagnostic capabilities of the various sectors before and after adjustment of the analysis for the disc-fovea angle.The disc-fovea angle was not different between the two groups (-7.0 ± 1.2° for controls vs. -6.6 ± 1.2° for POAG, P=0.70). There is a significant variance of this angle in both groups (the angle varies in the control group between -22.5° to +1.8° and in the POAG group between -18° to +2.4°). The global mean and inferior temporal (IT) thickness of the cpRNFL show the best diagnostic performance. Adjustment for disc-fovea angle does not increase the diagnostic accuracy of the various sectors analyzed. Although there is an increase in the area under the curve for the IT sector after adjustment, it is not statistically significant (0.910 ± 0.056 vs. 0.936 ± 0.045, P=0.06).There is a significant variation in disc-fovea angle. In this study, accounting for it does not significantly improve the diagnostic capabilities of cpRNFL in patients with POAG.

In order to answer statutory requirements and to anticipate the future needs and standards, the EFS is committed, since a few years, in a process of harmonization of its metrology function. In particular, the institution has opted for the skills development by internalizing the metrological traceability of the main critical quantities (temperature, volumetric) measurements. The development of metrology so resulted in a significant increase in calibration and testing activities. Methods are homogenized and improved through accreditations. The investment strategies are based on more and more demanding specifications. The performance of the equipments is better known and mastered. Technical expertise and maturity of the national metrology function today are assets to review in more informed ways the appropriateness of the applied periodicities. Analysis of numerous information and data in the calibration and testing reports could be pooled and operated on behalf of the unique establishment. The objective of this article is to illustrate these reflections with a few examples from of a feedback of the EFS Pyrénées Méditerranée. The analysis of some methods of qualification, the exploitation of the historical metrology in order to quantify the risk of non-compliance, and to adapt the control strategy, analysis of the criticality of an instrument in a measurement process, risk analyses are tools that deserve to be more widely exploited for that discipline wins in efficiency at the national level.

To develop an external quality control procedure for CyberKnife(®) beams. This work conducted in Nancy, has included a test protocol initially drawn by the medical physicist of Nancy and Lille in collaboration with Equal-Estro Laboratory.A head and neck anthropomorphic phantom and a water-equivalent homogeneous cubic plastic test-object, so-called "MiniCube", have been used. Powder and solid thermoluminescent dosimeters as well as radiochromic films have been used to perform absolute and relative dose studies, respectively. The comparison between doses calculated by Multiplan treatment planning system and measured doses have been studied in absolute dose. The dose distributions measured with films and treatment planning system calculations have been compared via the gamma function, configured with different tolerance criteria.This work allowed, via solid thermoluminescent dosimeter measurements, verifying the beam reliability with a reproducibility of 1.7 %. The absolute dose measured in the phantom irradiated by the seven participating centres has shown an error inferior to the standard tolerance limits (± 5 %), for most of participating centres. The relative dose measurements performed at Nancy and by the Equal-Estro laboratory allowed defining the most adequate parameters for gamma index (5 %/2mm--with at least 95 % of pixels satisfying acceptability criteria: γ1). These parameters should be independent of the film analysis software.This work allowed defining a dosimetric external quality control for CyberKnife(®) systems, based on a reproducible irradiation plan through measurements performed with thermoluminescent dosimeters and radiochromic films. This protocol should be validated by a new series of measurement and taking into account the lessons of this work.

A recent survey among French anesthesiologists revealed that monitoring of curarization is used in approximately in 50% of cases after a unique dose of curare and in 75% of cases after repeated doses of curare. In this survey, a majority of clinicians used a quantitative monitor based on acceleromyography, i.e. that the majority of clinicians used a device from the TOF-watch(®) product line. Results obtained by these monitors depends on the model used, TOF-Watch(®), TOF-Watch S(®) or TOF-Watch SX(®), as well as if it is used for a single point measurement at the end of the operation or continuously throughout the operation, with or without calibration, and if a calibration is used, should we used Cal 1 or Cal 2? Technical specifications and their impact on results will be developed in this technical note. This will help clinicians to better interpret results obtained by TOF-watch(®) monitors in order to improve clinical decisions based on monitoring of neuromuscular transmission.

This article examines the expected exercise-induced changes in the components of the oxygen transport system as described by the Fick equation with a view to enable a critical analysis of a standard incremental exercise test to identify normal and abnormal patterns of responses and generate hypotheses as to potential physiological and/or pathophysiological causes. The text reviews basic physiological principals and provides useful reminders of standard equations that serve to integrate circulatory, respiratory and skeletal muscle functions. More specifically, the article provides a conceptual and quantitative framework linking the exercise-induced increase in whole body oxygen uptake to central circulatory and peripheral circulatory factors with the view to establish the normalcy of response. Thus, the article reviews the exercise response to cardiac output determinants and provides qualitative and quantitative perspective bases for making assumptions on the peripheral circulatory factors and oxygen use. Finally, the article demonstrates the usefulness of exercise testing as an effective integrative physiological approach to develop clinical reasoning or verify pathophysiological outcomes.

Accuracy of results depends on the traceability of the standards values to a reference system. According to the ISO 15189 requirements, the laboratory has to document the traceability of the value of the standards used.

The newly developed, high throughput, Vitros 3600 immunoassay system associates different technologies on board: MicroWell (analytes immunocapture), MicroSensor (visible interference analysis), and Intellicheck (real time process control for analytical error detection). During a three months period, Vitros 3600 system, ease of use, practicability and MicroSensor technology efficiency have been tested using the following assays: betaHCG, troponin, ferritin, aHBcT, HBsAg, aHCV, AFP and CEA. Within-day and within-batch, between-calibration precisions are acceptable. Overall assay correlations versus the methods in use in our laboratory are good, despite small numerical differences that never affect clinical interpretation of the results. We have appreciated the system reliability, reinforced by the ease of use (simple software, on-board VDocs, continuous access to reagent and sample loading, reagent stability, very low noise (60 dB)), the quality of the results, MicroSensor and Intellicheck technologies efficiency, the short maintenance time and its traceability, and the very low liquid waste volume (5 L of liquid waste for 1600 tests). In conclusion and considering its practicability, the Vitros 3600 system is fully validated and well suited for our laboratory.

We had for aim to describe and illustrate the artefacts observed in biopsies of the oral mucosa, as well as the impact of sending non-representative histological material to a laboratory. This article was based on an international literature review, as well as on our experience. We analysed the problems raised, for the pathologists and the histology lab-technicians, by these artefacts as well as their impact on the pathology report patient management. We suggest simple solutions.

Stereotactic radiation therapy, consisting in irradiating the tumor with a high dose per fraction, has a therapeutic potential because of excellent local control. This technique requires a high accuracy level in order to minimize the risk of normal tissue toxicity. Initially used for cerebral localization, the stereotactic radiation therapy can be used for lung and liver tumors thanks to personalized immobilization devices, time resolved tomodensitometry for tumor deformation, collimators with small size leaves, advanced dose distribution calculation algorithms and 3D imaging for patient set-up. This article will review the different clinical applications and the different aspects (mechanical, dosimetric and biological) to evaluate before implementing this complex irradiation technique using adapted or dedicated linear accelerators.

This paper presents the development of a protocol for quality control of a megavoltage cone beam CT imaging system (MVCB) mounted on a Siemens Oncor 6MV linear accelerator.Several parameters were controlled on the MVCB system: (1) the initial geometric calibration of the system; (2) the quality of the images (geometric distortion, uniformity, spatial resolution, low contrast resolution) for various protocols; (3) the correspondence between the intensity of voxels and electronic densities; (4) the dose delivered when achieving a MVCB. These tests were done mainly with two cylindrical phantoms specific to the quality control (QC) of a MVCB system, supplied by Siemens, and with the Catphan 600 phantom (The Phantom Laboratory) and Quasar Multipurpose Body phantom (Modus Medical Devices Inc).The results of the quality control of the images were within the tolerances. The use of the Catphan 600 phantom was inadequate for the QC of MVCB images. These tests also highlighted the need to correct the MVCB images for the "cupping artefact" for dose calculation purpose.The initial characteristics of the MVCB imaging system were established. Such testing also provided the assessment of the influence of various parameters on the image quality as well as the associated dose delivered during their acquisition, and emphasized the corrections needed to use MVCB images for dose calculation.

Few information are available regarding the learning curve in ultrasonography and even less for ultrasound-guided regional anesthesia. This study aimed to evaluate in a training program the learning curve on a phantom of 12 residents novice in ultrasonography.Twelve trainees inexperienced in ultrasonography were given introductory training consisting of didactic formation on the various components of the portable ultrasound machine (i.e. on/off button, gain, depth, resolution, and image storage). Then, students performed three trials, in two sets of increased difficulty, at executing these predefined tasks: adjustments of the machine, then localization of a small plastic piece introduced into roasting pork (3 cm below the surface). At the end of the evaluation, the residents were asked to insert a 22 G needle into an exact predetermined target (i.e. point of fascia intersection). The progression of the needle was continuously controlled by ultrasound visualization using injection of a small volume of water (needle perpendicular to the longitudinal plane of the ultrasound beam). Two groups of two different examiners evaluated for each three trials the skill of the residents (quality, time to perform the machine adjustments, to localize the plastic target, and to hydrolocalize, and volume used for hydrolocalization). After each trial, residents evaluated their performance using a difficulty scale (0: easy to 10: difficult).All residents performed the adjustments from the last trial of each set, with a learning curve observed in terms of duration. Localization of the plastic piece was achieved by all residents at the 6th trial, with a shorter duration of localization. Hydrolocalization was achieved after the 4th trial by all subjects. Difficulty scale was correlated to the number of trials. All these results were independent of the experience of residents in regional anesthesia.Four trials were necessary to adjust correctly the machine, to localize a target, and to complete hydrolocalization. Ultrasonography in regional anesthesia seems to be a fast-learning technique, using this kind of practical training.

L-carnitine is a quaternary ammonium compound that facilitates long-chain fatty acids crossing through the mitochondrial membrane allowing their beta-oxidation. Human pathologies relatives to carnitine are mainly deficiencies, with myopathy and lipids metabolism disorders. The aim of this study was to validate the free and total carnitine plasmatic level measurement using the Dimension HM, X-Pand model analyzer (Dade Behring). Free carnitine was directly determined on plasma samples, deproteinized by using ultrafiltration, whereas total carnitine was measured after alkaline hydrolysis. Within-day and between-day imprecision were4,00 and 9,00 % respectively. The method is linear through 250,00 micromol/L and the limit of quantification is 3,00 micromol/L. Our method was correlated to tandem mass spectrometry (r = 0,956 for free and total carnitine). Recovery of free and total carnitine from spiked plasmas was99 %. On board stability of cartridge (5 days) and of calibration (at least 30 days) are in agreement with a method easily adaptable in routine laboratories.

Proteins identified in biological fluids of cancer patients could be helpful for both diagnosis and prognosis. However, clinical proteomics based on analysis of protein profiles in biological fluids has demonstrated various flaws, most of them related to the difficulties met in reproducibility. These difficulties could be partly overcome by accurate standardisation of pre-analytical and analytical steps of these studies. The size of the patient cohort is one of the parameters that determine the powerfulness of the study. Recruitment of a cohort with a sufficient size often implies multicentric studies in which analysis of the reproducibility between centres and standardisation of pre-analytical and analytical steps are essential. Such a standardisation requires the use of calibrated samples as common references.

cote interne IRCAM: Almeida07a; None / None; National audience; This article proposes a characterization of the double reed in quasistatic regimes. The nonlinear relation between the pressure drop, delta p, in the double reed and the volume flow crossing it, q, is measured for slow variations of these variables. The volume flow is determined from the pressure drop in a diaphragm replacing the instrument's bore. Measurements are compared to other experimental results on reed instrument exciters and to physical models, revealing that clarinet, oboe, and bassoon quasistatic behavior relies on similar working principles. Differences in the experimental results are interpreted in terms of pressure recovery due to the conical diffuser role of the downstream part of double-reed mouthpieces (the staple).

The purpose of this study was to evaluate retrospectively the indications, surgical technique, and postoperative findings in a series of 35 patients presenting lumbar canal stenosis due to osteoarthritic degeneration who underwent surgery using a tubular system for muscle retraction.This retrospective analysis included 35 patients, 28 with lumbar canal stenosis on a single level and seven with stenosis on two levels. On the stress images, 8 of these 35 patients presented stable degenerative spondylolisthesis. The surgical technique consisted in using a tubular system for muscle retraction. This enabled access for magnification and microsurgery of the canal, which was opened via an interlaminal approach. Concentric endocanal treatment was thus achieved without laminectomy. The same surgeon performed these 35 operations. The following variables were noted: patient age, level of canal narrowing, initial symptoms, duration of the operation, postoperative pain, use of analgesics, duration of hospital stay, clinical outcome at one and six months.The postoperative period (mean postoperative stay 2.5 days) was generally uneventful with little pain (mean VAS 0.8). This can be explained by the absence of invasive dissection. Disinsertion of the paravertebral muscles and use of elevators can induce muscle ischemia. The spine is not destabilized since laminectomy is avoided. The six-month outcome showed relief of the initial symptom for 84% of patients. There were two dural breaches with no clinical impact and one patient required revision surgery because of destabilization of a degenerative spondylolisthesis. One other patient also required revision for complementary laminectomy.The short-, mid-, and long-term results of spinal canal recalibration using a less invasive approach to lumbar canal stenosis via a tubular system for muscle retraction has provided encouraging results in terms of symptom relief. The early postoperative period is short and uneventful allowing earlier resumption of daily activities. This technique reduces the cost of hospitalization and drugs and is adapted for geriatric patients. The long-term outcome with this technique should be assessed in terms of spinal stability after recalibration.

The treatment with methotrexate at high doses is responsible of many side effects. It's necessary to evaluate serum methotrexate rate to monitor the administration of the methotrexate antagonist, the folinic acid. The aim of this study is to validate the determination of methotrexate in plasma using the automate Xpand Dimension (Dade Behring). Assay results were linearly related to the concentration for the wide range which was examinated (0.15 - 1.4 micromol/L). We report the precision, accuracy, linearity, sensitivity of this assay. The CV was less than 10%. We present the results of correlations with Aca (Dade Behring) and Cobas Mira (Roche). The reagent cartridge in the instrument and the calibration are stable during 28 days.

31P MRS and 1H MRI of skeletal muscle have become major new tools allowing a complete non invasive investigation of muscle function both in the clinical setting and in basic research. The comparative analysis of normal and diseased muscle remains a major requirement to further define metabolic events surrounding muscle contraction and the metabolic anomalies underlying pathologies. Also, standardized rest-exercise-recovery protocols for the exploration of muscle metabolism by P-31 MRS in healthy volunteers as well as in patients with intolerance to exercise have been developed. The CRMBM protocol is based on a short-term intense exercise, which is very informative and well accepted by volunteers and patients. Invariant metabolic parameters have been defined to characterize the normal metabolic response to the protocol. Deviations from normality can be directly interpreted in terms of specific pathologies in some favorable cases. This protocol has been applied to more than 4,000 patients and healthy volunteers over a period of 15 years. On the other hand, MRI investigations provide anatomical and functional information from resting and exercising muscle. From a diagnostic point of view, dedicated pulse sequences can be used in order to detect and quantify muscle inflammation, fatty replacement, muscle hyper and hypotrophy. In most cases, MR techniques provide valuable information which has to be processed in conjunction with traditional invasive biochemical, electrophysiological and histoenzymological tests. P-31 MRS has proved particularly useful in the therapeutic follow-up of palliative therapies (coenzyme Q treatment of mitochondriopathies) and in family investigations. It is now an accepted diagnostic tool in the array of tests which are used to characterize muscle disorders in clinical routine. As a research tool, it will keep bringing new information on the physiopathology of muscle diseases in animal models and in humans and should play a role in the metabolic characterization of gene and cell therapy.

According to requirements of the French Committee for Accreditation (Cofrac), it is essential to use validated and standardised methods in Immunohematology. This imposes first the knowledge of metrological tolerances for all the technics. Two multicenter studies were carried out to define the maximal acceptable deviations concerning incubation temperature and time, volumes of patient plasma and tests cells for antibody screening using indirect antiglobulin test on one hand and for reverse grouping on another hand. All equipment used (temperature test chamber, chronometer, pipettes) were calibrated according to Cofrac standards. The antibody screenings were performed manually using 3 different filtration systems: ID Diamed, Biovue Ortho and Scangel Biorad, the same tests cells, a standard 20 ng/mL anti RH1, a positive control anti KEL1 and a negative control; the reverse blood grouping was performed manually using the above mentionned filtration systems and microplate technic with the same A1 and B test cells. These two studies showed that all the tests from the multiples combinations of the above parameters gave the same results and allowed us to define a range of tolerance for 4 critical physical parameters involved in the antibody screening and blood typing.

Although the reliability of the electronic apex locator is agreed upon in the endodontic literature, the general practitioner has difficulties to integrate the device in his daily practice. The authors of this paper conclude that the apex locator should be used to confirm the information obtained from the pre-operatory radiograph (imperatively taken with the parallel technique) and they assert that the data obtained electronically have still to be interpretated. The apex locator can be considered an essential tool as long as its limitations are known.

The clinical setting defines the use of different methodology to detect allergen-specific IgE antibodies. In primary care, near the patient detection methods are useful as alternative to skin tests. The use of quantitative screening methods for atopy (Phadiatop) has been shown to improve the allergy diagnosis by the practicionner Such methods are very useful for their negative predictive value. Moreover, the dissociation between seasonal and perennial allergy is easier. For the use of specialist, quantitative results of allergen-specific IgE can be related to the probability of a clinical reaction to a given allergen. Clinical decision points have been established for common food allergens associated with atopic eczema in children.

A high-performance liquid chromatography method was developed for the rapid determination of ciprofloxacin in human serum. After protein precipitation, chromatographic separation of ciprofloxacin in plasma was achieved with an octyl column and 20 mmol/L phosphate buffer, methanol and acetonitrile 76/12/12 (v/v/v), pH 4, as mobile phase. Quantitative determination was monitored on a fluorescence detector using an excitation and emission wavelength of 278 and 450 nm, respectively. Enrofloxacin was used as internal standard. Calibration curve is linear over the range 0,12 to 20 microg/mL (r=0,9992). Limit of detection and limit of quantification are 0,04 and 0,12 microg/mL, respectively. Within-day coefficient of variation (2,0 to 3,1 %) and day-to-day coefficient of variation (4,3 to 5,5 %) at three different concentrations are sufficient. Relative recovery ranged from 91,1 to 94,0 % at three different concentrations. Each analysis requires no longer than 7 min.

The authors present the diode-pumped, all-solid state, neodymium:glass femtosecond laser from the Laboratory of Ocular Biotechnology, Hotel-Dieu Hospital.We worked with a 1,065-nm wavelength infrared laser. This laser is composed of an oscillator and amplification glass matrix mixed with neodymium. Its stretching and compression system is capable of producing pulses lasting a few hundred femtoseconds. The repetition rate is adjustable, ranging from 1 to 10 kHz, and can reach energies up to 60 microJ. The delivery system was set up on an optical table, with human corneal samples fixed to an anterior chamber system, which can be moved over the X-Y-Z axis by a computer-guided translation motor with micrometric precision. We analyzed the biological effects of laser impacts in human corneal tissue, obtained from the French Eye Bank.The femtosecond laser provides automated corneal cutting with a high level of precision, which can be verified on the corneal surface regularity by scanning electron microscopy analysis. Silicon samples can also be cut and can be used for calibration testing of the laser.The set-up composed of the femtosecond laser and the described delivery system enable precise corneal cutting and offer the opportunity to study its characteristics.

Lepirudin is an alternative anticoagulant therapy in heparin-induced thrombocytopenia (HIT) during cardiopulmonary bypass (CPB). We report a case of a female patient with HIT referred for aortocoronary bypass graft despite persistence of antibodies to platelet factor 4-heparin complexes. Anticoagulation management is described. Whole blood hirudin concentration attempted during CPB was above 4 microg ml(-1). To obtain this concentration, lepirudin administration was managed as follows: 0.1 mg kg(-1) h(-1) lepirudin during preoperative course, 0.2 mg kg(-1) bolus just before CPB and 0.2 mg kg(-1) in the priming solution, complementary boluses of 5 and 10 mg during procedure (according to whole blood ecarin clotting time). Aprotinin was administered simultaneously according to Royston protocol. Anticoagulation was monitored with whole blood ecarin time performed in the operation room (patient's whole blood was diluted one half and one third with normal whole blood; in vitro calibration curve was constructed using normal whole blood spiked with lepirudin). CPB duration was 73 min. When measured, whole blood hirudin concentration was 3.8-5.8 microg ml(-1). Total lepirudin administration was 44 mg. No haemorrhagic or thrombotic events were observed during surgical procedure and postoperative course. Despite lepirudin administration is not yet clearly precise for CPB procedure, its use seems adapted and safe in subjects without renal insufficiency but requiring precise coordination for anaesthesiological, surgical and biological teams.

The decimal visual acuity chart is not easy to use for statistical analysis and requires a transformation into LogMAR units (decimal logarithm of the Minimum Angle Resolution). In contrast to the decimal chart, the logarithmic chart has an arithmetic progression and a constant interval between lines. The LogMAR chart makes statistical analysis of visual acuity easy. Change in visual acuity is calculated directly by subtracting LogMAR data, while the average visual acuity is obtained with the arithmetic mean value of the LogMAR data. The mean acuity expressed in LogMAR units can be transformed into a decimal chart for a more comprehensive result. To calculate the average visual acuity directly from the decimal data, the geometric mean value must be used instead of the arithmetic mean value.

The Advia 70 hematology system is a new automated analyser manufactured in Texas (USA) by MWI-DANAM and marketed by Bayer- Diagnostics in France. The throughput is 70 complete blood counts (CBC) with leukocyte differential counts (diff) per hour. Three sample modes are proposed: normal mode (180 muL of whole blood), sample saver mode (90 muL) or automatic sampler (180 muL). The principles used on Advia 70 are: 1) electrical impedance for cell counting (WBC, RBC, platelets, MCV) and RBC/plt sizing; 2) multi-dimensional optical system and absorbance for white cell differential. The Advia 70 has been evaluated in our laboratory over a three-week period. Within-run variations of blood counting (CBCdiff) were determined on normal and abnormal patient specimens whereas between run-variations were determined on normal controls. Linearity and detection limits were also tested. The Advia 70 system results were reproducible and reliable. The correlations between the various sample modes were very good. Contamination and store assays were performed. Thirty normal and abnormal samples were successively analysed on the Advia 70 system and on the Advia 120 system which methodologies are different (myeloperoxidase staining coupled with flow cytometry-nuclear lobularity analysis for WBC/Diff, flow cytometry and laser diffraction for RBC/platelets), and the results were compared: despite the different technologies used on both analysers, the correlations were very good (CBC and diff parameters). Finally, we evaluated the leukocyte differential flags on 72 patients samples with abnormal cells, using the blood smear examination as the reference method. In conclusion, the Advia 70 can be used in private and hospital laboratories.

Diagnosis and management of hypertension is based on blood pressure (BP), as measured by auscultatory method. However, the devices are rarely checked making the quality of the measures doubtful.To compare BP measured according to the WHO recommendations using 2 different devices: the mercury or aneroid sphygmomanometer used by the physician and a SECURUS manometer that has been calibrated just before the implementation of the study.This is a randomised study performed with 1,336 French general practitioners (GP). Each GP received a calibrated SECURUS before the start of the study and was asked to include 2 treated hypertensive patients and one newly diagnosed patient. BP was measured 3 times with each device at 2 different visits. The devices were used in a random order: the order, at the 1st visit, was always the same for all the patients for a given GP. At the second visit the order of the devices was reversed. Patients were classified as normal (BP140/90 mm Hg) or high BP with each device at each visit.3,992 patients were included in the study (2,751 treated hypertensive patients). SECURUS BP measures were rounded up to 0 or 5 by 69% of the GPs and BPs with their own device by 77% of the GPs. A difference between the 2 devices5 mmHg was observed in nearly 10% of the GPs for SBP and 4% of the GPs for DBP. At the second visit, 13% of the treated hypertensive patients and 12% of the newly diagnosed patients and in whom no antihypertensive drug treatment has been introduced were not classified as having normal or high BP value in the same way by the 2 devices.This study confirms the results of a previous pilot study and emphasises the need of BP measurements respecting the guidelines in clinical practice, because of the possible impact on patient care and related costs.

A high-performance liquid chromatographic method has been developed for the determination of eight antiretroviral drugs (amprenavir, indinavir, lopinavir, nelfinavir, ritonavir, saquinavir, efavirenz and nevirapine) in a single run. After a liquid-liquid extraction with diethylether, the antiretroviral drugs are separated on a Stability RP18 column eluted with a gradient of acetonitrile and phosphate buffer (50 mM pH 5.65). A sequential ultraviolet detection allowed for simultaneous quantitation of antiretroviral drugs (240, 215, 260 nm). Calibration curves were linear in the range 100-10,000 ng/ml. The limit of quantitation was 50 ng/ml for all drugs except for nevirapine (100 ng/ml). The accuracies ranged from 88.2% to 110.9% and both inter- and intra-day coefficients of variation were lower than 11%. The extraction recoveries were higher than 62%. This method is simple and shows good specificity with respect to commonly coprescribed drugs.

Having had the opportunity of testing two of the three commercially available single use unit systems (i-STAT and OPTI-1), we have listed a series of performance limiting factors which they share, even though, their detectors being based on different methodologies, they have specific causes of dysfunction. PO2 detectors face the worse problems for different reasons. Temperature control is critical: the cassette or at last the detectors, the internal solution and the specimen have to be heated to 37 C, thermostabilisation to one tenth of degree centigrade is a must. Gas equilibration between liquid phases, the outside ambiance and the plastic material can raise problems: a decrease of the external barometric pressure alters the result, an absence of oxygen buffer capacity can induce modifications of the PO2 in the solutions. The transition of the detectors from a dry to a wet stage can provoke changes of the final result in case of accidental pre-humidication of the cassette. The presence of a single internal solution generates problems linked to a single point calibrage procedure which is a source of variability. The general quality of the cassette can only be evaluated by numerous internal electronic checks: increasing the severity of the controls improves quality but increases the number of rejected cassettes. External quality control through classical procedures are not applicable and finally the quality of the cassettes depends primarily on rigorous manufacturing conditions.

The atrial septal defects (ASDs) occlusion by cardiac catheterization is an alternative to the surgical technique. The use of stretching by balloon is considered as the gold-standard for the ASDs calibration. Three dimensional transesophageral echocardiography (3D-TEE) brings an imaging of the ASD surface and allows the measurement of its maximal diameter. With the goal of a percutaneous ASD occlusion, seventy patients had a simultaneous calibration of the ASDs by 3D-TEE and the balloon method. The mean maximal diameter measured by 3D-TEE was at 20 + 15 mm (range 10-28 mm) compared to the mean balloon-stretched diameter at 22 + 5 mm (range 9-31 mm). The correlation between both methods is good (y = 3.15 + 0.77x, r = 0.8, p0.0001). The mean difference between the diameters measured by both methods was 1.85 + 3.17 mm. The ASD visualized by 3D-TEE was single in 54 cases and multiple in 16 cases. The correlation between both methods was excellent in those with a single ASD (y = 1.74 + 0.84x; r = 0.85. p0.0001) but it was poor in those with multiple ASD (y = 12.4 + 0.4x; r = 0.45). The calibration by the balloon method which tests the septum resistance is an additive method to 3D-TEE which measures the anatomic diameter of ASD.

Results of catalytic activities of enzymes are highly dependent on the measurement procedures and on local conditions. Thus, only poorly marked improvement of interlaboratory comparability of results have been observed in clinical enzymology. To solve this problem, SFBC and IFCC have proposed to use "validated enzyme calibrators". Standardised operating procedures adapted to 37 C have been developed by IFCC for the most commonly used enzymes in clinical chemistry, and will be soon published. Reference materials which have been certified with these SOPs can be used as calibrators for a set of measurement methods which exhibit the same analytical specificity. Calibrators must be commutable, a property that must be checked experimentally. It is possible to produce stable and commutable materials for the calibration of a set of methods. Interest of this approach has been demonstrated for several enzymes. Results of two studies presented here show that the comparison of results to the upper limit of reference ranges does not improve the interlaboratory comparability of results in contrast to the calibration of different methods by a common calibrator which allowed to reach an interlaboratory CV close to 4% for ALT and gammaGT.

Until now, organ-cultured corneal endothelial mosaic has been assessed in France by cell counting using a calibrated graticule, or by drawing cells on a computerized image. The former method is unsatisfactory because it is characterized by a lack of objective evaluation of the cell surface and hexagonality and it requires an experienced technician. The latter method is time-consuming and requires careful attention. We aimed to make an efficient, fast and easy to use, automated digital analyzer of video images of the corneal endothelium.The hardware included a PC Pentium III ((R)) 800 MHz-Ram 256, a Data Translation 3155 acquisition card, a Sony SC 75 CE CCD camera, and a 22-inch screen. Special functions for automated cell boundary determination consisted of Plug-in programs included in the ImageTool software. Calibration was performed using a calibrated micrometer. Cell densities of 40 organ-cultured corneas measured by both manual and automated counting were compared using parametric tests (Student's t test for paired variables and the Pearson correlation coefficient).All steps were considered more ergonomic i.e., endothelial image capture, image selection, thresholding of multiple areas of interest, automated cell count, automated detection of errors in cell boundary drawing, presentation of the results in an HTML file including the number of counted cells, cell density, coefficient of variation of cell area, cell surface histogram and cell hexagonality. The device was efficient because the global process lasted on average 7 minutes and did not require an experienced technician. The correlation between cell densities obtained with both methods was high (r=+0.84, p0.001). The results showed an under-estimation using manual counting (2191+/-322 vs. 2273+/-457 cell/mm(2), p=0.046), compared with the automated method.Our automated endothelial cell analyzer is efficient and gives reliable results quickly and easily. A multicentric validation would allow us to standardize cell counts among cornea banks in our country.

The risk of dysphagia after antireflux surgery seems to be increased with laparoscopy compared with open surgery. Calibration of the hiatus is usually done by the surgeon's finger during open surgery. The aim of this study was to assess the results of laparoscopic calibration with a Fogarty balloon catheter.Between 1999 and 2001, 21 patients had a laparoscopic Toupet 240 degrees fundoplication with hiatus calibration using a 4 ml-inflated 8G Fogarty balloon catheter. These patients were compared with a group of 21 patients without hiatus calibration, matched for age, sex, preoperative dysphagia and esophageal dysmotility. Judgment criteria was early and/or late postoperative dysphagia (3 months).Median follow-up was 13 months. The rate of early dysphagia with and without calibration were 66% and 48% respectively (NS). Median duration of early dysphagia with and without calibration were 25 and 43 days respectively (p = 0.05). No patient with calibration had late dysphagia. One patient (5%) without calibration had unexplained late dysphagia for 2 years. He had preoperative esophageal dysmotility without oesophagitis.Hiatus calibration with a Fogarty balloon catheter decreased early postoperative dysphagia duration after Toupet laparoscopic fundoplication. This easily reproducible technical point standardizes the hiatus closure and should be recommended.

Aim of the research has been the evaluation of an image processing technique suggested for measuring procedures in the field of dental materials and devices studies. An analysis of measurement systems and largest employment's equipments in the biotechnologies field has been performed. Particularly, digital and image processing technologies have been considered and, between them, an evaluation of "Image Tool" software, made by UTHSCSA and available freeware on Internet has been carried out. The "Image Tool" software showed to be easy in handling and reliable on this results. Since it is based on image processing, the measuring precision is related to subject to be evaluated dimensions and always in the 1/1000 tolerance. This software also allow the direct surfaces measuring and comparing. The process accuracy is at the same level of mechanical regulation's measuring instruments (calipers, micrometres, surface probes) but it is not comparable to the laser controlled equipments, like CAD-CAM systems, micrometres and surface explores, precision which are much more sophisticated and expensives.

During the National Multicentric Study concerning the introduction of NAT for HCV and HIV-1 viruses in blood donation screening which was supervised by the Medical and Scientific departments of the French Blood Establishment (Etablissement français du sang--EFS), Transcription-Mediated transcription Amplification (TMA) technology (Chiron/Gen Probe) was experimented in the Molecular Biology Laboratory of Montpellier, EFS Pyrénées-Méditerranée. After a preliminary phase of qualification of the material and training of the technicians, routine screening of homologous blood and apheresis donations using this technology was applied for two months. In order to evaluate the different NAT systems, exhaustive daily operations and data were registered. Among these, the luminescence results expressed as RLU of the positive and negative calibrators and the associated internal controls were analysed using Control Charts, Statistical Process Control methods, which allow us to display rapidly process drift and to anticipate the appearance of incidents. This study demonstrated the interest of these quality control methods, mainly used for industrial purposes, to follow and to increase the quality of any transfusion process. it also showed the difficulties of the post-investigations of uncontrolled sources of variations of a process which was experimental. Such tools are in total accordance with the new version of the ISO 9000 norms which are particularly focused on the use of adapted indicators for processes control, and could be extended to other transfusion activities, such as blood collection and component preparation.

In clinical practice, diagnosis and follow-up of hypertension is based on blood pressure (BP) as measured by auscultatory method. BP is usually measured using a stethoscope to auscultate the Korotkoff sounds and mercury or an aneroid sphygmomanometer. However due to the lack of regulatory rules, the devices are rarely checked making the quality of the measures doubtful.To compare BP measured following the WHO recommendations, using 2 different devices: the mercury or aneroid sphygmomanometer used by the physician and a SECURUS manometer that has been calibrated just before the implementation of the study.The study was performed with 1694 French general practitioners. Every physician included 2 ambulatory patients: a newly diagnosed non-treated hypertensive patient and a treated hypertensive patient. The physician was asked to include the first patient of each category attending his office. BP was measured sequentially with the 2 devices in a random order. Collected data were socio-demographic parameters, cardiovascular risk factors, hypertension related diseases, drug treatment for hypertension and BP levels.Mean BPs differ by less than 1 mmHg between the 2 devices. However 10% of the treated hypertensive patients are not classified as having normalised BP values (BP140/90 mmHg) or high BP values, in the same way by the 2 devices. Mean absolute difference between the 2 devices is5 mmHg in 22% and 13% of the physicians for SBP and DBP respectively.This pilot study emphasises the need of BP measurements of good quality in clinical practice, because of the possible impact on the care of the patients and the related costs. Regulatory rules on the control of the devices might improve the quality of BP measurements.

The large metrological variation (CV, about 25%) observed between laboratories, at the national French level, for the measurement of enzymatic activities results in a loss of efficiency in using laboratory results. Current data show that the standardisation of methods is insufficient to solve this problem and needs to be completed by an harmonisation of the practices including the use of a common reference (calibrator). The present work, carried out by the joint working group between laboratories of the Centres for Periodic Health Examination and the French Society of Clinical Biology (SFBC), deals mainly with the feasibility and evaluation of the improvement of the consistency of the results. Twenty laboratories participated in this study. Five independent surveys were conducted during an height month period. Two enzymes were selected because of their clinical importance and their interest in prevention, screening, diagnosis or epidemiology: ALT (alanine aminotransferase) and GGT (gamma-glutamyltransferase). In each survey three kinds of samples i.e. control sera, candidate calibrators and human serum pools, each of them at two levels of activity (one physiological and the other pathological) were measured in duplicate. The low intra-laboratory imprecision and the high degree of the standardisation of used methods, due to an important effort previously done in this field, permitted to consider a common calibration. The stability and mainly the commutability, i.e. the ability for the candidate calibrator to show a behaviour similar to that of human samples towards the used methods, allowed to reduce the inter-laboratory variation by a half to two third-fold, reaching a coefficient of variation5% similar to those observed for cholesterolemia or glycemia. This level of consistency should permit to use common reference limits and common decision limits, after validation of this approach in real practice. The consequences of the harmonisation of practices, extended to the all laboratories, exceed largely the scope of this study. The reduction of the uncertainty and a better approach of the accuracy for the measurement of enzymatic activities should led to a real benefit for the patients in terms of prevention, screening, diagnosis or therapeutic monitoring and consequently for the public health.

We used 3D ultrasonographic reconstruction with manual acquisition to study the volume of venous clots in vitro.Native 2D ultrasound slices were acquired free hand for 3D reconstruction. The spatial coordinates of each slice were delivered in real time with an electromagnetic captor. We applied a standard ultrasound protocol to test the calibrated 3D reconstruction quantitatively. The volume of 5 clots of increasing size was quantified in vitro using manual segmentation in a double-blind manner by two independent operators.The comparison tests and the interoperator regression lines evidenced good agreement between real and measured volumes, confirming the coherence of the reconstruction protocol and the feasibility of this technique in a routine medical setting. Intraoperator variability was 7 to 11% and interoperator variability 16.9%.This calibrated 3D reconstruction is compatible with in vitro measurement of venous clots. This technique could be useful to follow the evolution of the head of proximal deep vein thrombi in vivo. It will be more reliable with semi-automatic or even automatic segmentation becomes available.