Tunnel positioning assessment after anterior cruciate ligament reconstruction at 12months: Comparison between 3D CT and 3D MRI. A pilot study.

BACKGROUND: Tunnel positioning assessment is a major issue after anterior cruciate ligament (ACL) reconstruction surgery. Historically, it used plain X-ray and, more recently, CT with 3D reconstruction. MRI is a reliable method of assessing ACL graft integrity and postoperative complications. To our knowledge, there have been no studies of efficacy in tunnel positioning assessment. The aim of this study was to assess the efficacy of 3D MRI in assessing femoral and tibial tunnel positioning after ACL reconstruction. The hypothesis was that 3D MRI sequences with reconstruction are as accurate as 3D CT for tunnel positioning assessment in ACL reconstruction. METHODS: Twenty-two patients who underwent an arthroscopic ACL reconstruction using hamstring graft were included in a prospective study. All patients were examined on 3D CT and 3D MRI at 12months post-surgery. Tunnel positioning was assessed on both imaging systems by a musculoskeletal radiologist and an orthopedic surgeon specialized in knee arthroscopy, both blind to all clinical data. RESULTS: No statistically significant difference was found between 3D CT and 3D MRI on coronal and sagittal reconstructions. For coronal assessment of tibial tunnel orifice, sagittal assessment of tibial tunnel orifice and sagittal assessment of femoral tunnel orifice, P-values ranged from 0.37 to 0.99, 0.051 to 0.64 and 0.19 to 0.59, respectively. For tibial and femoral tunnel angulation, P-values were respectively 0.52 and 0.29. CONCLUSION: 3D MRI is a reliable method to assess femoral and tibia tunnel positioning in ACL reconstruction, compared to 3D CT as gold standard. Indeed, in our opinion 3D MRI could in the future replace CT for ACL reconstruction assessment, concerning not only the meniscus and ligaments but also tunnel position. LEVEL OF EVIDENCE: Level 3; comparative prospective study.

Evaluating variability and uncertainty in radiological impact assessment using SYMBIOSE.

SYMBIOSE is a modelling platform that accounts for variability and uncertainty in radiological impact assessments, when simulating the environmental fate of radionuclides and assessing doses to human populations. The default database of SYMBIOSE is partly based on parameter values that are summarized within International Atomic Energy Agency (IAEA) documents. To characterize uncertainty on the transfer parameters, 331 Probability Distribution Functions (PDFs) were defined from the summary statistics provided within the IAEA documents (i.e. sample size, minimal and maximum values, arithmetic and geometric means, standard and geometric standard deviations) and are made available as spreadsheet files. The methods used to derive the PDFs without complete data sets, but merely the summary statistics, are presented. Then, a simple case-study illustrates the use of the database in a second-order Monte Carlo calculation, separating parametric uncertainty and inter-individual variability.

[Oocyte vitrification and its impact on the clinical practice of assisted reproduction]. / La vitrification des ovocytes et les changements induits dans nos pratiques d'AMP.

Oocyte vitrification is a new technique in cryobiology that will lead to a number of improvements in assisted reproduction practices, oocyte donation and the preservation of female fertility. Professionals already versed in the techniques of micromanipulation will be able to master the new procedures, which should not be delegated to unqualified staff. When adopted by clinical units, oocyte vitrification will require changes in laboratory and administrative organization. The technique will also modify the ethical outlines of reproductive biology. France today is running behind in the application of this major development in cryobiology. The reasons are many and have to do with a long waiting period for authorization from national health authorities, a lack of material and human resources and a foreseeable shake-up in the nationally established egg donation program. However, recently a new law of bioethics has recognized the breakthrough that this new technique represents by allowing couples covered by the French national health care program for Assisted Reproductive Technologies (ART) to choose oocyte vitrification as an option.

Does fibrin sealant use in total knee replacement reduce transfusion rates? A non-randomised comparative study.

BACKGROUND: Studies assessing fibrin sealants use during total knee replacement (TKR) have produced inconsistent results. We evaluated fibrin sealant therapy in TKR procedures performed without tourniquet and without postoperative drains. HYPOTHESIS: Use of a fibrin sealant during TKR decreases calculated total blood loss, thereby diminishing blood transfusion requirements and costs. PATIENTS AND METHODS: We studied 62 patients with primary knee osteoarthritis who underwent TKR by the same surgeon between September 2009 and December 2010. Fibrin sealant was used only in the last 31 patients, who were compared to the first 31 patients regarding calculated total blood loss, blood transfusion rate, and mean number of red-blood-cell units used per patient. Costs were compared in the two groups. RESULTS: In the control group, mean total blood loss calculated using the method of Gross was 1.3±0.6 L, 48% of patients required blood transfusions, and the mean number of units per patient was 0.9±1. In the fibrin-sealant group, 29% of patients required blood transfusions and the mean number of units was 0.6±0.9. The between-group differences in favour of the fibrin-sealant group were not statistically significant. In each group, compared with patients not requiring blood transfusions, patients needing transfusions had significantly lower starting preoperative haemoglobin values and a significantly greater positive difference between the calculated total blood loss and the maximum allowable blood loss. In the test group, the cost of the 31 units of fibrin sealant was 9743€ and the cost reduction due to using 11 fewer red-blood-cell units was only 3484€. Hospital stay was not significantly shorter in any of the two groups. DISCUSSION: Blood transfusion minimisation during TKR should rely chiefly on correcting preoperative anaemia and optimizing transfusion decisions based on the difference between the total blood loss and the maximum allowable blood loss. Fibrin sealant did not significantly diminish transfusion requirements in our study. Randomised studies in larger patient populations are needed. The cost of fibrin sealant may exceed the expected cost savings in relation with decreased blood transfusion requirements. LEVEL OF EVIDENCE: Level III (before-after therapeutic study).

Computerised Decision Support Systems for the management of freshwater radioecological emergencies: assessment of the state-of-the-art with respect to the experiences and needs of end-users.

Assessment of the environmental and radiological consequences of a nuclear accident requires the management of a great deal of data and information as well as the use of predictive models. Computerised Decision Support Systems (CDSS) are essential tools for this kind of complex assessment and for assisting experts with a rational decision process. The present work focuses on the assessment of the main features of selected state-of-the-art CDSS for off-site management of freshwater ecosystems contaminated by radionuclides. This study involved both developers and end-users of the assessed CDSS and was based on practical customisation exercises, installation and application of the decision systems. Potential end-users can benefit from the availability of several ready-to-use CDSS that allow one to run different kinds of models aimed at predicting the behaviour of radionuclides in aquatic ecosystems, evaluating doses to humans, assessing the effectiveness of different kinds of environmental management interventions and ranking these interventions, accounting for their social, economic and environmental impacts. As a result of the present assessment, the importance of CDSS "integration" became apparent: in many circumstances, different CDSS can be used as complementary tools for the decision-making process. The results of this assessment can also be useful for the future development and improvement of the CDSS.

CASTEAUR: a simple tool to assess the transfer of radionuclides in waterways.

The CASTEAUR project proposes a simplified tool to assess the transfer of radionuclides between and in the main biotic and abiotic components of the freshwater ecosystem. Applied to phenomenological modeling, various hypotheses simplify the transfer equations, which, when programmed under Excel, can be readily dispatched and used. CASTEAUR can be used as an assessment tool for impact studies of accidental release as well as "routine" release. This code is currently being tested on the Rhone River, downstream from a nuclear reprocessing plant. The first results are reported to illustrate the possibilities offered by CASTEAUR.

[Assessment of normal growth patterns in rats by Z score]. / Evaluación del crecimiento normal en ratas a través del puntaje Z.

Malnutrition is one of the most important causes of normal growth disruption. Anthropometric methods are highly valuable in clinic pediatric diagnosis to determine the nutritional status of children and as recovery monitoring. In previous studies, we have demonstrated that the standards weight-age, height-age and weight-height of growing rats had similar distribution to those in normal children. However, to improve the diagnostic effectiveness of anthropometric information, statistical analysis to normally and non-normally distributed variables should be applied. One hundred Wistar rats (50 male and 50 female rats) from weaning (day = 25, weight = 35-40 g) to 70 days of age were fed with a commercial diet. Water and diet were offered "ad libitum". Body weight and height were recorded every two or four days, respectively. Percentiles of weight vs age, height vs age and weight vs height were plotted for male and female rats. The statistical criterion for classifying the anthropometric measurements into nutritional categories was based on percentiles cutoff and Z-score. The Z-score was calculated according to: Z = (standard mean value-subject value/standard deviation of standard). The statistical anthropometric categories of growing rats were similar to those obtained in children. This evidence suggest that the rat can be used as an experimental model to infer and predict the nutritional response in children.

Clinical and economic comparison of sertraline and fluoxetine in the treatment of depression. A 6-month double-blind study in a primary-care setting in France.

In a double-blind study in a primary-care setting in France, outpatients fulfilling DSM IV criteria for a major depressive episode were randomised to receive sertraline (50 to 150 mg/day; n = 122) or fluoxetine (20 to 60 mg/day; n = 120). Assessments, including clinical evaluation [Montgomery-Asberg Depression Rating Scale (MADRS), Clinical Global Impressions (CGI)] and quality of life [Functional Status Questionnaire (FSQ)], were made at study entry and after 4 and 6 months of treatment. Use of medical services, absences from work and productivity losses were recorded for calculation of direct and indirect costs from both the overall societal perspective and in terms of sickness insurance. In total, 231 patients (116 receiving sertraline, 115 receiving fluoxetine) were included in an intention-to-treat analysis assessed up to the last visit. Statistically significant clinical and quality-of-life improvements from baseline were observed in both treatment groups, with no between-group differences. Utilisation of medical resources was higher in fluoxetine-treated patients, with significantly more consultations with specialists. The 2 treatment groups were similar in terms of number of hospitalisations and duration of stay, whether related to depression or not. There were no significant differences between groups for work or productivity losses. Cost comparisons favoured sertraline treatment from both the societal (FF7780 vs FF8706) and sickness insurance (FF2936 vs FF3224) viewpoints, with cost differentials of FF926 and FF288, respectively. From the societal perspective, the total cost per patient over the 6-month course of the trial, irrespective of the study treatment given, was FF8241, and the corresponding sickness insurance cost was FF3079. At the time of the study, FF1 = $US0.1993.

Physicians confront the apocalypse. The American medical profession and the threat of nuclear war.

KIE: Boyer traces the American medical profession's involvement with the nuclear war issue from World War II to 1963. Research on the effects of radiation began with the Manhattan Project in 1942, and continued in Hiroshima and Nagasaki after the war. Interest in the narrow clinical aspects of radiation was rarely matched by an awareness of the social and medical implications of nuclear war, as attention focused instead on optimistic predictions about the benefits of atomic medicine. The medical community entered wholeheartedly into Cold War civil defense planning, and physicians and the public were encouraged to believe that a nuclear attack was survivable with advance planning. Medical activism against nuclear war began in the late 1950s and peaked in 1962 to 1963 with a series of New England Journal of Medicine articles, laying the foundation for physicians' renewed involvement in the 1980s.^ieng

Assessment of the rate of bound substrate interconversion and of ATP acceleration of product release during catalysis by mitochondrial adenosine triphosphatase.

The oxygen exchange parameters for the hydrolysis of ATP by the F1-ATPase have been determined over a 140,000-fold range of ATP concentrations and a 5,000-fold range of reaction velocity. The average number of water oxygens incorporated into each Pi product ranges from a limit of about 1.02 at saturating ATP concentrations to a limit of about 3.97 at very low ATP concentrations. The latter value represents 400 reversals of hydrolysis of bound ATP prior to Pi dissociation. In accord with the binding change mechanism, this means that ATP binding at one catalytic site increases the off constant of Pi and ADP from another catalytic site by at least 20,000-fold, equivalent to the use of 6 kcal mol-1 of ATP binding energy to promote product release. The estimated rate of reversal of hydrolysis of F1-ATPase-bound ATP to bound ADP + Pi varies only about 5-fold with ATP concentration. The rate is similar that observed previously for reversal of bound ATP hydrolysis or synthesis with the membrane-bound enzyme and is greater than the rate of net ATP formation during oxidative phosphorylation. This adds to evidence that energy input or membrane components are not required for bound ATP synthesis.

[Demographic dimensions of the world economic crisis]. / Dimensions demographiques de la crise economique mondiale

PIP: The author contends that aspects of the world economic crisis and the fertility decline in developed countries have origins in the disequilibrium in the age distribution of the population, caused by World War II and exacerbated by the rigidity of the employment structure. Theories linking the age structures of populations, global equilibrium in supply and demand, and capital accumulation are outlined. The impact of employment conditions on fluctuations in fertility as hypothesized by Easterlin is considered, and a regression model is applied to data for European and North American countries.^ieng