Odontoblastic differentiation of dental pulp stem cells from healthy and carious teeth on an original PCL-based 3D scaffold.

AIMS: To isolate and characterize dental pulp stem cells (DPSCs) obtained from carious and healthy mature teeth extracted when conservative treatment was not possible or for orthodontic reasons; to evaluate the ability of DPSCs to colonize, proliferate and differentiate into functional odontoblast-like cells when cultured onto a polycaprolactone cone made by jet-spraying and prototyped into a design similar to a gutta-percha cone. METHODOLOGY: DPSCs were obtained from nine carious and 12 healthy mature teeth. Then cells were characterized by flow cytometry and submitted to multidifferentiation to confirm their multipotency. These DPSCs were then cultured on a polycaprolactone cone in an odontoblastic differentiation medium. Cell proliferation, colonization of the biomaterial and functional differentiation of cells were histologically assessed. For the characterization, a t-Student test was used to compare the two groups. RESULTS: In all cell cultures, characterization highlighted a mesenchymal stem cell phenotype (CD105+, CD90+, CD73+, CD11b-, CD34-, CD45-, HLA-DR-). No significant differences were found between cultures obtained from carious and healthy mature teeth. DPSCs from both origins were able to differentiate into osteocytes, adipocytes and chondrocytes. Cell colonization was observed both on the surface and in the thickness of polycaprolactone cones as well as a mineralized pericellular matrix deposit composed of type I collagen, alkaline phosphatase, osteocalcin and dentin sialophosphoprotein. CONCLUSIONS: DPSCs were isolated from both carious and healthy mature teeth. They were able to colonize and proliferate within a polycaprolactone cone and could be differentiated into functional odontoblast-like cells.

Performance of manual ventilation: how to define its efficiency in bench studies? A review of the literature.

Bench studies have become the preferred way to evaluate the performance of airway equipment, since clinical trials are not specifically required before marketing these devices. However, it is difficult to assess the efficiency of ventilation without recording physiological data. This review analyses how efficiency of manual ventilation has been defined in recent studies, and how their results may be affected. We searched electronic databases from 2000 to April 2014. The main inclusion criterion was the analysis of performance of ventilation. Nine relevant articles were selected from 53 eligible publications. Most studies used the same parameters; tidal volume and ventilation rate. However, there were significant differences between the definitions of performance of ventilation, both in terms of criteria of judgement and methods of analysis. None of these approaches is able to provide a clear understanding of variability of ventilation during a given period. A new definition may increase the relevance of bench studies to clinical medicine, by more appropriately assessing the performance of ventilation.

Microclimate next to the skin: influence on percutaneous absorption of caffeine (ex-vivo study).

BACKGROUND/PURPOSE: Contact between skin surface and external environment induces a microclimate at the skin surface. That microclimate affects skin interaction with xenobiotics substances. We have developed a new device to explore the influence of environmental parameters, on percutaneous absorption. The aim of this study was to study the influence of external humidity and temperature on percutaneous absorption of caffeine. METHODS: Six exposure conditions were tested: four by combining two temperatures (27°C and 42°C) with two relative humidities (28% and 70%), performed by our device and two others by using Franz diffusion cell (unoccluded conditions, with skin surface in contact with ambient laboratory environment (27°C/33%) and in occluded conditions with skin surface covering by impermeable membrane). RESULTS: Kinetic curve profile of percutaneous absorption of caffeine revealed different shapes characteristics depending on environmental exposure conditions. These profiles were related to evaporative process, of deposited preparation on skin surface combined with water uptake resulting from water flux through skin. CONCLUSION: Our results highlight a preponderant role of microclimate above the skin on percutaneous absorption of caffeine. The device used in this study will be a useful tool to investigate ex vivo, the influence of microclimate on percutaneous absorption.

[Chronic wound care leads to the bacterial contamination of the environment]. / Les soins des plaies chroniques entraînent une contamination bactérienne de l'environnement.

AIM: The aim of this study was to determine levels of bacterial contamination of the environment during chronic wound dressing changes. METHODS: Sampling of chronic wounds and of the environment (air and surfaces) was performed during changing of chronic wound dressing. A series of samples was defined as the entire sample for a given day for a given patient. Five sequential samples of air and six samples of surfaces were taken for each series. Staphylococcus aureus, Pseudomonas aeruginosa and enterobacteria were specifically cultured. RESULTS: Thirty series of samples were taken for 26 different patients. Twenty-seven out of these 30 series were colonized with one or two of the target species. For 13 series of the latter samples (13/27, 48.1%), bacteria isolated from the wound were recovered in the environment, namely S. aureus and P. aeruginosa. The six enterobacteria isolated from wounds were not retrieved in the environment. Air samples were more often positive than surfaces samples. CONCLUSION: We demonstrated frequent contamination of the hospital environment with bacteria colonizing wounds during dressing changes. This indicates that wearing of masks and hand disinfection after contact with the environment constitute key measures in the control of bacterial cross-transmission.

Feasibility of two-dimensional ultrasound shear wave elastography of human fetal lungs and liver: A pilot study.

PURPOSE: The first aim was to evaluate feasibility and reproducibility of 2-dimensional ultrasound (2D) shear wave elastography (SWE) of human fetal lungs and liver between 24 and 34weeks of gestation. The second aim was to model fetal lung-to-liver elastography ratio (LLE ratio) and to assess its variations according to gestational age and maternal administration of corticosteroids. MATERIAL AND METHODS: 2D-SWE examinations were prospectively performed in fetuses of women with an uncomplicated pregnancy (group 1) and fetuses of women with a threatened preterm labor requiring administration of corticosteroids (group 2). Two 2D-SWE examinations were performed at "day 0" and "day 2" in group 1; before and 24hours after a course of corticosteroid in group 2. Three operators performed 2 cycles of 3 measurements on the lung (regions A1, A2, A3) and the liver (regions IV, V, VI). Repeatability and reproducibility of measurements were calculated. The fetal LLE ratio was modeled from the most reproducible regions. RESULTS: Fifty-five women were enrolled in group 1 and 48 in group 2. For the lung, 8.6% of measurements were considered invalid and 6.9% for the liver. The most reproducible region for the lung was A3 [ICC between 0.70 (95% CI: 0.42-0.85) and 0.78 (95% CI: 0.48-0.90)] and region VI for the liver [ICC between 0.70 (95% CI: 0.40-0.85) and 0.84 (95% CI: 0.60-0.94)]. According to gestational age, a moderate positive linear correlation was found for stiffness values of A3 (R=0.56), V (R=0.46) and VI (R=0.44). LLE ratio values at "day 0" were not different between the two groups but decreased at "day 2" in group 2 (0.2; 95% CI: 0.07-0.34; P<0.001). CONCLUSION: Quantitative fetal lung and liver stiffness measurements are possible with 2D-SWE with acceptable reproducibility.

Local ice cryotherapy decreases synovial interleukin 6, interleukin 1ß, vascular endothelial growth factor, prostaglandin-E2, and nuclear factor kappa B p65 in human knee arthritis: a controlled study.

BACKGROUND: The aim of this study was to assess the anti-inflammatory effects of local cryotherapy in human non-septic knee arthritis. METHODS: In the phase I of the study, patients were randomized to receive either ice (30 min; N = 16) or cold CO2 (2 min; N = 16) applied twice during 1 day at an 8-h interval on the arthritic knee. In phase II, 16 other ice-treated arthritic knees according to the same protocol were compared to the contralateral non-treated arthritic knees (N = 16). The synovial fluid was analyzed just before the first cold application, then 24 h later. IL-6, IL-1ß, TNF-α, IL-17A, VEGF, NF-kB-p65 protein, and PG-E2 levels were measured in the synovial fluid and compared before/after the two cold applications. RESULTS: Forty-seven patients were included (17 gouts, 11 calcium pyrophosphate deposition diseases, 13 rheumatoid arthritides, 6 spondyloarthritides). Local ice cryotherapy significantly reduced the IL-6, IL-1ß, VEGF, NF-kB-p65, and PG-E2 synovial levels, especially in the microcrystal-induced arthritis subgroup, while only phosphorylated NF-kB-p65 significantly decreased in rheumatoid arthritis and spondyloarthritis patients. Cold CO2 only reduced the synovial VEGF levels. In the phase II of the study, the synovial PG-E2 was significantly reduced in ice-treated knees, while it significantly increased in the corresponding contralateral non-treated arthritic knees, with a significant inter-class effect size (mean difference - 1329 [- 2232; - 426] pg/mL; N = 12). CONCLUSIONS: These results suggest that local ice cryotherapy reduces IL-6, IL-1ß, and VEGF synovial protein levels, mainly in microcrystal-induced arthritis, and potentially through NF-kB and PG-E2-dependent mechanisms. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03850392-registered February 20, 2019-retrospectively registered.

Evaluation of the clinical benefit of an electromagnetic navigation system for CT-guided interventional radiology procedures in the thoraco-abdominal region compared with conventional CT guidance (CTNAV II): study protocol for a randomised controlled trial.

BACKGROUND: Interventional radiology includes a range of minimally invasive image-guided diagnostic and therapeutic procedures that have become routine clinical practice. Each procedure involves a percutaneous needle insertion, often guided using computed tomography (CT) because of its availability and usability. However, procedures remain complicated, in particular when an obstacle must be avoided, meaning that an oblique trajectory is required. Navigation systems track the operator's instruments, meaning the position and progression of the instruments are visualised in real time on the patient's images. A novel electromagnetic navigation system for CT-guided interventional procedures (IMACTIS-CT®) has been developed, and a previous clinical trial demonstrated improved needle placement accuracy in navigation-assisted procedures. In the present trial, we are evaluating the clinical benefit of the navigation system during the needle insertion step of CT-guided procedures in the thoraco-abdominal region. METHODS/DESIGN: This study is designed as an open, multicentre, prospective, randomised, controlled interventional clinical trial and is structured as a standard two-arm, parallel-design, individually randomised trial. A maximum of 500 patients will be enrolled. In the experimental arm (navigation system), the procedures are carried out using navigation assistance, and in the active comparator arm (CT), the procedures are carried out with conventional CT guidance. The randomisation is stratified by centre and by the expected difficulty of the procedure. The primary outcome of the trial is a combined criterion to assess the safety (number of serious adverse events), efficacy (number of targets reached) and performance (number of control scans acquired) of navigation-assisted, CT-guided procedures as evaluated by a blinded radiologist and confirmed by an expert committee in case of discordance. The secondary outcomes are (1) the duration of the procedure, (2) the satisfaction of the operator and (3) the irradiation dose delivered, with (4) subgroup analysis according to the expected difficulty of the procedure, as well as an evaluation of (5) the usability of the device. DISCUSSION: This trial addresses the lack of published high-level evidence studies in which navigation-assisted CT-guided interventional procedures are evaluated. This trial is important because it addresses the problems associated with conventional CT guidance and is particularly relevant because the number of interventional radiology procedures carried out in routine clinical practice is increasing. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01896219 . Registered on 5 July 2013.

Protocol Design Challenges in the Detection of Awareness in Aware Subjects Using EEG Signals.

Recent studies have evidenced serious difficulties in detecting covert awareness with electroencephalography-based techniques both in unresponsive patients and in healthy control subjects. This work reproduces the protocol design in two recent mental imagery studies with a larger group comprising 20 healthy volunteers. The main goal is assessing if modifications in the signal extraction techniques, training-testing/cross-validation routines, and hypotheses evoked in the statistical analysis, can provide solutions to the serious difficulties documented in the literature. The lack of robustness in the results advises for further search of alternative protocols more suitable for machine learning classification and of better performing signal treatment techniques. Specific recommendations are made using the findings in this work.

Evaluation of Bag-Valve-Mask Ventilation in Manikin Studies: What Are the Current Limitations?

Introduction. Manikin-based studies for evaluation of ventilation performance show high heterogeneity in the analysis and experimental methods used as we pointed out in previous studies. In this work, we aim to evaluate these potential limitations and propose a new analysis methodology to reliably assess ventilation performance. Methods. One hundred forty healthcare providers were selected to ventilate a manikin with two adult self-inflating bags in random order. Ventilation parameters were analysed using different published analysis methods compared to ours. Results. Using different methods impacts the evaluation of ventilation efficiency which ranges from 0% to 45.71%. Our new method proved relevant and showed that all professionals tend to cause hyperventilation and revealed a significant relationship between professional category, grip strength of the hand keeping the mask, and ventilation performance (p = 0.0049 and p = 0.0297, resp.). Conclusion. Using adequate analysis methods is crucial to avoid many biases. Extrapolations to humans still have to be taken with caution as many factors impact the evaluation of ventilation performance. Healthcare professionals tend to cause hyperventilation with current devices. We believe this problem could be prevented by implementing monitoring tools in order to give direct feedback to healthcare professionals regarding ventilation efficiency and ventilatory parameter values.

On the difficulty to communicate with fMRI-based protocols used to identify covert awareness.

Assessment of awareness in patients with disorders of consciousness such as patients in a vegetative state (unresponsive wakefulness syndrome, UWS) and patients in a minimally conscious state (MCS) remains difficult, with a high rate of misdiagnosis (around 40%). While patients with UWS have no awareness, patients with MCS have partial preservation of conscious awareness. To improve the assessment of awareness in these patients, recent functional neuroimaging protocols have been developed. However, does the complexity of realizing and interpreting these functional magnetic resonance imaging (fMRI) investigation protocols, which are currently carried out by only a few specialist teams, permit generalizable use in clinical routine? In this study, 32 healthy volunteers, by definition perfectly conscious and able to efficiently communicate, performed the protocol proposed by Monti et al. in 2010. Four methods (comprising the method proposed by Monti et al., a mean squared error-based method, a correlation-based method, and a support vector machine-based method) were tested for correctly and accurately interpreting the communication task. Firstly, the different instructions for the localizer and the communication tasks had no effect on activations. Secondly, 25% of participants (8/32) did not provide the expected patterns of activations during fMRI tasks (four for each imagery task). However, this did not necessarily prevent the classification methods from correctly guessing the answers during the communication task. Conversely, these classification methods may fail to detect the correct answers even though participants activated the expected brain areas. None of the four methods produced 100% correct detection during the communication phases. The correlation-based method obtained the best results with an error rate of 4.2%. The results of this study demonstrate that fMRI-based communication paradigms may not be robust enough to reliably detect awareness in all aware patients. There is still a need to develop new statistical and analytical methods before considering their generalization in clinical routine.

Pilot study of feasibility of the effect of treatment with tDCS in patients suffering from treatment-resistant depression treated with escitalopram.

OBJECTIVE: This double-blind, sham-controlled trial investigated the effects of two daily tDCS sessions over a 5-day period in treatment-resistant depression. METHOD: Twenty-four treatment-resistant depressed patients received two daily sessions of active or sham anodal tDCS to the left prefrontal cortex (2 mA, 10 sessions over 1 week). Depression severity, psychomotor retardation and cognitive function were assessed. RESULTS: Active tDCS was not significantly superior to sham tDCS on the HDRS at week 4, as well as on the MADRS and SRRS scales, and on neuropsychological tests. Response rates were not significantly higher with active tDCS. tDCS was well tolerated, with mild adverse events limited to transient scalp discomfort. CONCLUSION: tDCS did not induce clinically relevant antidepressant effect in active and sham stimulation groups. There was no impact on psychomotor and neuropsychological functioning. SIGNIFICANCE: tDCS efficacy on specific symptom profiles in pharmacotherapy-resistant depression is limited. The use of optimized stimulation protocol and longer period of follow up may valuably contribute to specify the place of tDCS in treatment-resistant depression.

[3D printing in health care facilities: What legislation in France?]. / L'impression 3D à l'hôpital: quelle réglementation en France ?

Health care facilities more and more use 3D printing, including making their own medical devices (MDs). However, production and marketing of MDs are regulated. The goal of our work was to clarify what is the current French regulation that should be applied concerning the production of custom-made MDs produced by 3D printing in a health care facility. MDs consist of all devices used for diagnosis, prevention, or treatment of diseases in patients. Prototypes and anatomic models are not considered as MDs and no specific laws apply to them. Cutting guides, splints, osteosynthesis plates or prosthesis are MDs. In order to become a MD manufacturer in France, a health care facility has to follow the requirements of the 93/42/CEE directive. In addition, custom-made 3D-printed MDs must follow the annex VIII of the directive. This needs the writing of a declaration of conformity and the respect of the essential requirements (proving that a MD is secure and conform to what is expected), the procedure has to be qualified, a risk analysis and a control of the biocompatibility of the material have to be fulfilled. The documents proving that these rules have been respected have to be available. Becoming a regulatory manufacturer of MD in France is possible for a health care facility but the specifications have to be respected.

Substitute or complement? Defining the relative place of EEG and fMRI in the detection of voluntary brain reactions.

To improve the assessment of awareness in patients with disorders of consciousness, recent protocols using functional Magnetic Resonance Imaging (fMRI) have been developed, and led some specialized coma centers to use this method on a routine basis. Recently, promising results have also been observed with electroencephalography (EEG), a less expensive and widely available technique. However, since the spatiotemporal nature of the recorded signal differs between both EEG and fMRI, the question of whether one method could substitute or should complement the other method is a matter of debate. In this study, we compared the neural processes of two well-known EEG and fMRI mental imagery protocols to define the relative place of each method in the assessment of awareness. A group of 20 healthy volunteers performed both EEG and fMRI command-following and communication tasks. Distinct command following was found with both EEG and fMRI for five subjects, only with fMRI for 12 subjects, and only with EEG for one subject. In the communication task, neither EEG nor fMRI alone gave satisfactory results and no reliable communication could be established in approximately 1/3rd of the participants. If fMRI showed the best performance to detect volitional reactions in mental imagery tasks, our results provide evidence that the use of EEG must not be underestimated since a better detection was found with this method for at least one subject. More than being used as a substitute, EEG should complement fMRI to improve the detection of sign of awareness, and to reduce the risks of misjudgments.

Fetal heart rate monitoring by telephone during pregnancy--opinion of users and non-users of a new technology.

OBJECTIVE: To compare the opinions of obstetricians who currently use fetal heart rate monitoring (FHRM) by telephone with the opinions of obstetricians in favour of this technique, but who do not use it. STUDY DESIGN: A mail questionnaire was sent to the 612 members of a professional organization of obstetricians. The response rate was 76%. RESULTS: Fourteen percent of the respondents used FHRM by telephone and 43% did not use it, but were in favour of it. Compared with current users, non-users who were in favour of this technique indicated a wider range of clinical indications for monitoring, considered a greater proportion of women to be eligible, and wanted more frequent monitoring. These differences cannot be explained by the characteristics of the obstetricians (age, type of practice or attitude towards FHRM performed in maternity unit). CONCLUSION: Our survey shows a risk of extensive use of FHRM by telephone if this technique becomes easily accessible.

Including practice data to improve evidence-based guidelines. Example of guidelines on the management of thyroid nodules.

Although clinical guidelines are based on the best evidence available, their proliferation has often failed to change actual practice. One of the many explanations suggested is that there is a gap between the expectations of the targeted professionals and the recommendations in the guidelines. In this study, we attempted to take into account the state of current practice and the physicians' priorities. Using the example of guidelines on the management of thyroid nodules, three different surveys have been conducted: (1) an analysis of physicians' expectations and practice through a postal questionnaire to define appropriate questions; (2) a survey of the professionals' expert opinions, and (3) a prospective study of the use of these guidelines in the management of 253 patients. The results of these surveys have modified the development of the guidelines, and helped us to adapt the content of the guidelines to match physicians' practices more closely.

A method for guideline development: assessing practical feasibility and adaptation of thyroid nodule guidelines.

The objective of this study was to assess adaptation and feasibility of practice guidelines for thyroid nodule management. For one month physicians completed a self-administered semi-structured questionnaire concerning a draft version of the guidelines for each consecutive patient. A sample group of 20 endocrinologists, 20 surgeons and 120 general practitioners from all parts of France took part in this study. The main outcome measures were whether the case description was found by the physicians, and whether recommendations were found and agreement with these recommendations were assessed. We found that two hundred and fifty-three patients (of whom 85% were women) were included in the study: 52% were seen for a surgical decision; 20% for diagnosis or screening and 28% for follow-up. Four percent of the women were pregnant; 2% of the patients had a large nodule; and 2%, a retrosternal nodule. These last three situations had not been well identified in the draft guidelines. The patient's case description was appropriately identified in 75% of the responses. Most cases reported as being not found were, however, covered by the guidelines. Physicians in private practice were less likely than the others to identify their patient's cases. Physicians agreed with the recommendation in 77% of cases. General practitioners were more likely and endocrinologists less likely than surgeons to disagree. Most disagreements and alternative proposals were not evidence-based. Our conclusion is that this study shows that the draft guidelines were applicable, and allowed minor improvements of the final version. Adapting guidelines to practice could improve their use and, consequently, the quality of health care.

[What alternatives to rectal temperature recording with a mercury thermometer?]. / Quelles alternatives à la prise rectale de la température avec un thermomètre à mercure?

Fever is a major symptom to characterize individual health status. Measurement of temperature is systematically made in everyday medical practice. In France, this measurement is generally assumed with a rectal glass mercury thermometer. In order to protect people and the environment, the "Conseil Supérieur d'Hygiène Publique de France" has approved recommendations to withdrawn medical use of mercury, specifically for thermometer. Rectal measurement is also debated since infectious risks are described. Thus, substitution of rectal glass mercury thermometer is on the agenda. New sites and techniques for measurement of temperature have been studied through a literature review, interview of experts and companies, and clinical research protocols. Cutaneous and axillary measurements are inaccurate and unsatisfactory. Two methods seems to be worth: oral measurement and tympanic measurement. Oral measurement is widespread in the world. This technique has some limits. Tympanic measurement is a new method in progress without these limits. Whatever the choice of the technique is, the substitution of rectal glass mercury thermometer requires training and awareness of staff and patients.

[How to evaluate nursing practices?]. / Comment évaluer les pratiques de soins?

Assessment of clinical health care focuses on 'what is really done' in order to describe day-to-day practice. These data could be compared with standards or guidelines. The method used, the 'clinical audit', aims to improve the quality of care through specific actions. Finally, a second data collection could assess the efficacy of these actions. Many protocol designs could be used; they are illustrated by two examples in this article. The choice of protocols depends on the field and on the objectives of the work. Most of the time, assessment of clinical health care is included in a continuous quality improvement programme.

[Tumor markers in the cytodiagnosis of thyroid nodules. Detection of dipeptidyl aminopeptidase IV (DAP IV) activity]. / Marqueurs de malignité dans le cytodiagnostic des nodules thyroïdiens. Révélation de l'activité dipeptidyl aminopeptidase IV (DAP IV).

Dipeptidyl-aminopeptidase IV (DAP IV), an exopeptidase involved in T-cell activation is absent from normal thyroid tissue but highly expressed by malignant thyroid cells. It has been suggested to be a useful adjunct for the diagnosis of malignant thyroid tumors on fine needle aspirates (FNA). To assess this assumption DAP IV activity was demonstrated by histochemical staining on FNA performed on 102 thyroid nodules at the time of surgery (60 macrofollicular adenomas, 15 microfollicular adenomas. 7 Hashimoto's thyroïditis, 3 Graves' disease. 13 papillary carcinomas and 4 follicular carcinomas). A staining score based on the percentage of positive epithelial cells and staining intensity was established for each case and results were compared to histological diagnosis. Most cells in malignant tumors were deeply stained except in one case of papillary carcinoma. Null or very low scores resulting from light or medium staining of less than 40% of the cells were obtained in 78/85 benign nodules. In 6 macrofollicular adenomas and in 1 case of thyroiditis staining score was as as high as in carcinomas. DAP IV staining was correlated to malignancy in all follicular tumours (4 malignant tumours were positive and 15 benign were negative). The sensitivity for diagnosis of malignancy was 94.1% and the specificity 91.7%. This study brings confirmation that DAP IV activity detection could be an useful adjunct to cytological examination for the distinction between benign and malignant thyroid nodules, especially in cases of follicular tumors.