Evaluation of primary care physicians' competence in selective skin tumour triage after short versus long dermoscopy training: a randomized non-inferiority trial.

BACKGROUND: Although primary care physicians (PCPs) play a key role in skin cancer screening, their skills in detecting malignant tumours is suboptimal. OBJECTIVES: To determine whether a short dermoscopy e-learning course (4 h) in skin tumour diagnosis for PCPs is non-inferior to a long course (12 h) in selective triage of skin lesions. Secondly, to evaluate whether regular refresher training sessions are necessary to maintain the PCPs' skills in the medium term. METHODS: A randomized 2 × 2 factorial non-inferiority trial was conducted online over an 8-month period among 233 PCPs including 126 certified general practitioners, 94 PCPs in training, and 13 occupational physicians, all without prior advanced dermoscopy training. Participants were randomized 1:1:1:1 to receive short training and mandatory refreshers (n = 58), short training and optional refreshers (n = 59), long training and mandatory refreshers (n = 58), or long training and optional refreshers (n = 58). PCPs' skills were evaluated before training (T0), immediately after training (T1) to test the non-inferiority, and after 5 months (T2) to evaluate the impact of the refreshers. The primary endpoint was the difference in the change of score after short and long training. The non-inferiority margin was set at -28%. RESULTS: Among the 233 randomized participants, 216 (93%) completed T1 and 197 (84.5%) completed T2. For short versus long training, the primary endpoint was 1.392 (95% CI: 0.138; 2.645) in the per-protocol population (p < 0.001) and 1.016 (95% CI: -0.224; 2.256) in the modified intention-to-treat population (p < 0.001). After training, the type of refresher showed no impact on the score (p = 0.840). However, PCPs who completed all refreshers showed the best mean overall score at T2 (p < 0.001). CONCLUSIONS: These findings confirm that short dermoscopy e-learning is non-inferior in training PCPs to triage skin lesions compared to long training. After training, regular refreshers are important to maintain the PCPs' acquired skills over time.

Burden of visible [face and hands] skin diseases: Results from a large international survey.

BACKGROUND: While numerous surveys over the last decade have evaluated the burden of skin diseases, none have focused on the specific impact of disease-location on the hands and face. AIM: The purpose of our study was to evaluate the burden of 8 skin diseases on the multidimensional aspects of subjects' daily lives in respect to their location on visible body areas (face or hands) versus non-visible areas. METHODS: This was a population-based study in a representative sample of the Canadian, Chinese, Italian, Spanish, German and French populations, aged over 18 years using the proportional quota sampling method. All participants were asked (i) to complete a specific questionnaire including socio-demographic characteristics, (ii) to declare if they had a skin disease. All respondents with a skin disease were asked (iii) to specify the respective disease locations (hands, face, body) and (iv) to complete the DLQI questionnaire. Respondents with 8 selected skin diseases were asked (v) to complete a questionnaire evaluating the impact of the skin disease on their daily life, including their professional activity, social relations, emotional and intimate life, leisure, sports activities and perceived stigma. RESULTS: A total of 13,138 adult participants responded to the questionnaire, of whom 26.2 % (n = 3,450) had skin diseases, and 23.4 % (n = 3,072) reported having one of the 8 selected skin diseases. Fifty-three percent were women and the mean age was 39.6 ±â€¯15.5 years. The QoL was mostly impaired when the visible localization was solely on the hands as compared with the face (38 % had a DLQI > 10 versus 22 % respectively). More subjects with a visible localization on the hands reported felt-stigma, having difficulty falling asleep and felt that their sex life had been affected. CONCLUSION: Special attention should be given to patients with skin disease on the hands and face as they are at higher risk of social exclusion and lower quality of life.

Novel organic semiconductors based on 2-amino-anthracene: Synthesis, charge transport and photo-conductive properties.

Anthracene is considered to be a popular choice as a building block for organic semiconductors. The present work is dedicated to the synthesis and characterization of a novel semiconductor (10-OPIA) possessing mesogenic properties, which allows better control over charge transport in the bulk of a material. A novel anthracene-based molecule is characterized for its potential applications: frontier molecular energy levels are studied by optical spectroscopy and cyclic voltammetry and compared to values obtained via ab initio calculations. Thermophysical and mesogenic properties are investigated by optical microscopy and differential scanning calorimetry. Charge transport properties are characterized by means of an OFET device. It is found that this material can be easily aligned and exhibits a field effect hole mobility of 5.22 × 10-5 cm2 V-1 s-1 and an ON/OFF ratio of 104 in the device prepared by drop casting. Finally, the photoconductive properties of this novel material are addressed in order to investigate its potential applications for organic phototransistors: it exhibits a large photoconductive gain of >100 and a photo-responsivity of >1 A W-1.

Impact of acne on the daily life of adult patients: building a self-administered patient questionnaire.

BACKGROUND: Acne is a long-lasting disease in adolescents and adults impacting the patient's daily life. Currently, there is no specific questionnaire that assesses its impact in adult patients. AIM: To build a self-administered questionnaire assessing the impact of acne on the daily life in adult patients. METHOD: A multidisciplinary working group was created, including 3 experts in healthcare questionnaires and dermatologists specialized in acne. A questionnaire using a standardized methodology for designing self-administered patient questionnaires according to conceptual, development and validation phases was developed. A cultural and linguistic validation into US English was conducted, based on the original French version. RESULTS: A 14-item questionnaire demonstrating consistency, reproducibility and high reliability was build. The questionnaire significantly correlated with the SF-12 mental and SF-12 physical scores and CADI, indicating good external validity. CONCLUSION: The present acne burden questionnaire AI-ADL allows the practioner to assess quickly and easily the burden of acne in patients during his daily clinical practice. Moreover, its short format allows patients to express easily and quickly their feelings and to initiate a conversation between the practioner and his patient. Thus, AI-ADL may help to better understand the multidimensional nature of acne, as well as the individual impact on the acne patient's daily life and moreover, it may play a key role in the decision-making process of treatment initiation and involvement of the patient in the management of his acne.

Molecular p-doping in organic liquid crystalline semiconductors: influence of the charge transfer complex on the properties of mesophase and bulk charge transport.

We explore the molecular nature of doping in organic semiconductors (OSCs) by employing a liquid crystalline organic semiconductor based on phenyl naphthalene as a model. The mesophase nature of composites that include a charge transfer complex (CTC) between the OSC (8-PNP-O12) and an electron acceptor (F4TCNQ) has been investigated by means of differential scanning calorimetry, polarized optical microscopy and X-ray scattering. Optical and vibrational spectroscopies allow us to explore the characteristics and the amount of charge transfer in the CTC and expose some properties that appear only in the complexed state. We have found this system to exhibit partial charge transfer, which manifests itself in all the phase states of the host 8-PNP-O12, as well as in solution. Due to the lowering of molecular symmetry as a result of the charge transfer, one of the previously IR-only vibrational bands of the nitrile group is found to be now active in the Raman spectrum. We have also made an attempt to further investigate the influence of dopant introduction on the bulk hole mobility of 8-PNP-O12. It is found that the presence of the CTC promotes the hole transport in the Smectic B mesophase, however it seems to have a somewhat negative influence in the less ordered smectic A mesophase. This work aims to establish the link between the inevitable change of molecular geometry that occurs on charge transfer with the results obtained by spectroscopic techniques and electronic charge carrier mobility measurements.

Allochthonous matter: an important factor shaping the phytoplankton community in the Baltic Sea.

It is well-known that nutrients shape phytoplankton communities in marine systems, but in coastal waters allochthonous dissolved organic matter (ADOM) may also be of central importance. We studied how humic substances (proxy of ADOM) and other variables influenced the nutritional strategies, size structure and pigment content of the phytoplankton community along a south-north gradient in the Baltic Sea. During the summer, the proportion of mixotrophs increased gradually from the phosphorus-rich south to the ADOM-rich north, probably due to ADOM-fueled microbes. The opposite trend was observed for autotrophs. The chlorophyll a (Chl a): carbon (C) ratio increased while the levels of photoprotective pigments decreased from south to north, indicating adaptation to the darker humic-rich water in the north. Picocyanobacteria dominated in phosphorus-rich areas while nanoplankton increased in ADOM-rich areas. During the winter-spring the phytoplankton biomass and concentrations of photoprotective pigments were low, and no trends with respect to autotrophs and mixotrophs were observed. Microplankton was the dominant size group in the entire study area. We conclude that changes in the size structure of the phytoplankton community, the Chl a:C ratio and the concentrations of photoprotective pigments are indicative of changes in ADOM, a factor of particular importance in a changing climate.

Design of experiments in medical physics: Application to the AAA beam model validation.

PURPOSE: The purpose of this study is to evaluate the usefulness of the design of experiments in the analysis of multiparametric problems related to the quality assurance in radiotherapy. The main motivation is to use this statistical method to optimize the quality assurance processes in the validation of beam models. METHOD: Considering the Varian Eclipse system, eight parameters with several levels were selected: energy, MLC, depth, X, Y1 and Y2 jaw dimensions, wedge and wedge jaw. A Taguchi table was used to define 72 validation tests. Measurements were conducted in water using a CC04 on a TrueBeam STx, a TrueBeam Tx, a Trilogy and a 2300IX accelerator matched by the vendor. Dose was computed using the AAA algorithm. The same raw data was used for all accelerators during the beam modelling. RESULTS: The mean difference between computed and measured doses was 0.1±0.5% for all beams and all accelerators with a maximum difference of 2.4% (under the 3% tolerance level). For all beams, the measured doses were within 0.6% for all accelerators. The energy was found to be an influencing parameter but the deviations observed were smaller than 1% and not considered clinically significant. CONCLUSION: Designs of experiment can help define the optimal measurement set to validate a beam model. The proposed method can be used to identify the prognostic factors of dose accuracy. The beam models were validated for the 4 accelerators which were found dosimetrically equivalent even though the accelerator characteristics differ.

Electric field effects on phase transitions in the 8CB liquid crystal doped with ferroelectric nanoparticles.

The influence of a low ac electric field on phase transitions is discussed in the case of a nematic liquid crystal 4-n-octyl-4^{'}-cyanobiphenyl (8CB) doped with Sn_{2}P_{2}S_{6} ferroelectric nanoparticles. The phase-transition temperatures obtained from temperature-dependent dielectric measurements were higher than those determined by the calorimetric method. This difference is explained by the presence of the measuring electric field which induces two effects. The first one is the amplification of the interactions between the nanoparticle polarization and the liquid-crystal order parameter. The second one is the field-induced disaggregation or aggregation process at high nanoparticle concentrations.

Interactions of grape tannins and wine polyphenols with a yeast protein extract, mannoproteins and ß-glucan.

At present, there is a great interest in enology for yeast derived products to replace aging on lees in winemaking or as an alternative for wine fining. These are yeast protein extracts (YPE), cell walls and mannoproteins. Our aim was to further understand the mechanisms that drive interactions between these components and red wine polyphenols. To this end, interactions between grape skin tannins or wine polyphenols or tannins and a YPE, a mannoprotein fraction and a ß-glucan were monitored by binding experiments, ITC and DLS. Depending on the tannin structure, a different affinity between the polyphenols and the YPE was observed, as well as differences in the stability of the aggregates. This was attributed to the mean degree of polymerization of tannins in the polyphenol fractions and to chemical changes that occur during winemaking. Much lower affinities were found between polyphenols and polysaccharides, with different behaviors between mannoproteins and ß-glucans.

Allochthonous Carbon--a Major Driver of Bacterioplankton Production in the Subarctic Northern Baltic Sea.

Heterotrophic bacteria are, in many aquatic systems, reliant on autochthonous organic carbon as their energy source. One exception is low-productive humic lakes, where allochthonous dissolved organic matter (ADOM) is the major driver. We hypothesized that bacterial production (BP) is similarly regulated in subarctic estuaries that receive large amounts of riverine material. BP and potential explanatory factors were measured during May-August 2011 in the subarctic Råne Estuary, northern Sweden. The highest BP was observed in spring, concomitant with the spring river-flush and the lowest rates occurred during summer when primary production (PP) peaked. PLS correlations showed that ∼60% of the BP variation was explained by different ADOM components, measured as humic substances, dissolved organic carbon (DOC) and coloured dissolved organic matter (CDOM). On average, BP was threefold higher than PP. The bioavailability of allochthonous dissolved organic carbon (ADOC) exhibited large spatial and temporal variation; however, the average value was low, ∼2%. Bioassay analysis showed that BP in the near-shore area was potentially carbon limited early in the season, while BP at seaward stations was more commonly limited by nitrogen-phosphorus. Nevertheless, the bioassay indicated that ADOC could contribute significantly to the in situ BP, ∼60%. We conclude that ADOM is a regulator of BP in the studied estuary. Thus, projected climate-induced increases in river discharge suggest that BP will increase in subarctic coastal areas during the coming century.

Distinct localizations and roles of non-muscle myosin II during proplatelet formation and platelet release.

BACKGROUND: At the end of maturation, megakaryocytes (MKs) form long cytoplasmic extensions called proplatelets (PPT). Enormous changes in cytoskeletal structures cause PPT to extend further, to re-localize organelles such as mitochondria and to fragment, leading to platelet release. Two non-muscle myosin IIs (NMIIs) are expressed in MKs; however, only NMII-A (MYH9), but not NMII-B (MYH10), is expressed in mature MKs and is implicated in PPT formation. OBJECTIVES: To provide in vivo evidence on the specific role of NMII-A and IIB in MK PPT formation. METHODS: We studied two transgenic mouse models in which non-muscle myosin heavy chain (NMHC) II-A was genetically replaced either by II-B or by a chimeric NMHCII that combined the head domain of II-A with the rod and tail domains of II-B. RESULTS AND CONCLUSIONS: This work demonstrates that the kinetic properties of NM-IIA, depending on the N-terminal domain, render NMII-A the better NMII candidate to control PPT formation. Furthermore, the carboxyl-terminal domain determines myosin II localization in the constriction region of PPT and is responsible for the specific role of NMII in platelet release.

Linear mixed-effects models for central statistical monitoring of multicenter clinical trials.

Multicenter studies are widely used to meet accrual targets in clinical trials. Clinical data monitoring is required to ensure the quality and validity of the data gathered across centers. One approach to this end is central statistical monitoring, which aims at detecting atypical patterns in the data by means of statistical methods. In this context, we consider the simple case of a continuous variable, and we propose a detection procedure based on a linear mixed-effects model to detect location differences between each center and all other centers. We describe the performance of the procedure as a function of contamination rate and signal-to-noise ratio. We investigate the effect of center size and variance structure and illustrate the use of the procedure using data from two multicenter clinical trials.

Health-related quality of life in patients with melanoma expressed as utilities and disability weights.

BACKGROUND: Few studies about health-related quality of life (HRQoL) in patients with melanoma have expressed their results in terms of utilities or disability weights (DWs). Utilities are required for calculating quality-adjusted life years and therefore for cost-effectiveness analyses. DWs are useful to assess the burden of diseases through disability-adjusted life years. OBJECTIVES: To provide utilities and DWs regarding patients with melanoma. METHODS: The patients were classified into eight groups using four stages based on the 2009 American Joint Committee on Cancer stages, with each stage subdivided into treatment and remission phases. The EuroQoL Five Dimensions Five Levels (EQ-5D-5L) questionnaire was completed by the patients with melanoma to provide a mean utility for each group. In addition to this, the EuroQoL visual analogue scale (VAS) and a validated quality-of-life questionnaire dedicated to patients with melanoma [Functional Assessment of Cancer Therapy Melanoma (FACT-M)] were completed by the same patients in order to compare their results with the obtained utilities. DWs were obtained by calculating, for each patient, the difference between his/her utility and the corresponding sex- and age-specific population norm. RESULTS: A total of 395 questionnaire sets were completed. Utilities and DWs showed significant differences between follow-up groups. Treatment groups had similar utilities and DWs but these results were obtained during different treatment durations and therefore have different weights. The VAS and the FACT-M were found to be less sensitive. Nevertheless, the FACT-M identified some problems not found by the EQ-5D-5L questionnaire. CONCLUSIONS: The EQ-5D-5L questionnaire seems adequate to provide utilities and DWs in patients with melanoma. Lower HRQoL in female patients with melanoma is probably linked to lower HRQoL in the general population.

[Motivational interviewing use for promoting health behavior: an approach of doctor/patient relationship]. / L'entretien motivationnel dans la promotion des comportements de santé : une approche de la relation médecin/malade.

Many situations in common medical practice, especially in chronic diseases, require patients to be mobilized for health behavior decisions: for daily intake of an antihypertensive drug, performing a mammography for cancer screening, as well as adopting new diet habits in diabetes. Ability to initiate a health behavior depends on several parameters. Some of them are related to the patient, his personality, his illness and treatment's perception; others directly rely on the physician, his attitude and his communication style during the visit, independently of patient's level of resistance to change. Motivational interviewing (MI) is a communication technique, first developed for patients presenting a substance abuse disorder, to explore their ambivalence, overcome their resistances and give them the willingness of a better self-care. Its general principles and basic techniques can be applied by every practitioner and deserve to be better known, given that scientific literature provides evidence for generalizing it in a variety of medical conditions, in structured patient education programs as well as in usual follow-up, for which time is generally restricted. This article provides an overview of MI recent applications and argues for its diffusion in everyday medical practice.

Impaired sexual activity in young ischaemic stroke patients: an observational study.

BACKGROUND AND PURPOSE: The present study sought to determine the impact of stroke on sexual function and well-being in a cohort of young ischaemic stroke patients and identify factors associated with impairment. METHODS: Over a 2-year period, all patients aged 60 or under with ischaemic stroke or transient ischaemic attack (n = 156) were included. Information on sexual function and well-being was obtained by means of a paper questionnaire mailed to participants 1 year after their stroke. Impaired sexual activity (ISA) was defined as a decline in sexual function and/or satisfaction. Psychological well-being was evaluated on the Hospital Anxiety and Depression Scale (HADS). RESULTS: The response rate was 67% (n = 104). Thirty of these responders (29%) reported ISA. Patients with ISA had a higher HADS score (19.7 vs. 11.2 in patients with no impairment; P < 0.001), anxiety score (10.0 vs. 6.3; P < 0.001) and depression score (8.7 vs. 4.8; P < 0.001) and were more likely to have left brain lesions (70% vs. 30%; P < 0.001) and use angiotensin-converting enzyme (ACE) inhibitors (73% vs. 31%; P < 0.001) and diuretics (50% vs. 19%; P = 0.003). In a stepwise logistic regression, depression (odds ratio 9.1, 95% confidence interval 2.45-33.46; P = 0.001) and ACE inhibitor use (odds ratio 6.0, 95% confidence interval 2.11-17.28; P = 0.001) were associated with ISA. CONCLUSIONS: Impaired sexual activity was reported by almost one-third of younger patients 1 year after ischaemic stroke. Factors associated with post-stroke ISA may include specific medications and depression rather than the characteristics of the stroke per se.

Experimental determination of the effective point of measurement and the displacement correction factor for cylindrical ionization chambers in a 6 MV photon beam.

The displacement effect of cylindrical ionization chambers is taken into account either by an effective point of measurement (EPOM) or, alternatively, by using a displacement correction factor. The dependence of these effects on water was examined as a function of the cavity radius for (60)Co gamma radiation in a previous paper. This paper describes results for high-energy photon beams using the same measurement technique. Additionally, the displacement correction factor was directly measured. Absorbed doses measured under reference conditions following the international protocol IAEA TRS-398 and the German protocol DIN 6800-2 agreed well between the chambers with different cavity radii within a standard uncertainty of 0.2%. However, there was a constant difference of 0.2% between both protocols. Similar to our observations made in (60)Co, absorbed doses measured with the different chambers at depths beyond the maximum showed deviations of up to 0.6% and 0.5% for IAEA TRS-398 and DIN 6800-2, respectively, and deviations of more than 1% were found for both protocols in the build-up and maximum region. We therefore propose modified formulas for the determination of the EPOM and the displacement correction factor.

Experimental determination of the effective point of measurement for cylindrical ionization chambers in 60Co gamma radiation.

The displacement effect of cylindrical ionization chambers is taken into account either by an effective point of measurement (EPOM) or, alternatively, by using a displacement perturbation factor. The dependence of these effects in water was examined as a function of the cavity radius using cylindrical chambers with different radii and a plane-parallel chamber, whose EPOM is well known. Depth-dose curves were measured in terms of absolute absorbed dose in water and evaluated according to the international protocol IAEA TRS-398 as well as the German protocol DIN 6800-2. As expected, evaluation of absorbed dose under reference conditions following both protocols agreed well within a standard uncertainty of 0.1%. However, values of absorbed dose at depths beyond the dose maximum showed deviations up to 0.3% and 0.5% for IAEA TRS-398 and DIN 6800-2, respectively. Values in the build-up and maximum region did not agree very well. Deviations of more than 1% were found for both protocols. It was concluded that the corrections recommended in both protocols are not fully appropriate. A procedure is suggested to measure the absorbed depth-dose distribution including the build-up region with an improved accuracy by means of cylindrical chambers.

Availability of digital dermoscopy in daily practice dramatically reduces the number of excised melanocytic lesions: results from an observational study.

BACKGROUND: Digital dermoscopy has been shown to permit an earlier detection of melanoma. However, few studies have investigated its added value in reducing unnecessary excisions in everyday clinical practice. OBJECTIVES: To compare, in daily practice, the efficiency of three dermoscopy methods: dermoscopy alone with little training, dermoscopy alone with adequate training and dermoscopy with adequate training and access to digital dermoscopy, and to confirm the safety of this latter approach. METHODS: Thirty-six dermatologists working without digital dermoscopy were divided into two groups according to their training in dermoscopy. The third group constituted of two dermatologists working in a pigmented lesion clinic with access to the digital dermoscopy technique and eight additional dermatologists working in the same dermatology department. These 46 dermatologists included all presumed melanocytic lesions excised over a period of 1 year. The primary endpoint was the melanoma/nonmelanoma ratio (M/NM-R); secondary endpoints were the ratio of 'problem' naevi to common naevi (PN/CN-R), specificity and sensitivity for the diagnosis of melanoma, in situ/invasive melanoma ratio, and the mean Breslow thickness. RESULTS: In total, 1865 excised lesions, including 231 melanomas, were included. In the digital dermoscopy availability group (DD-G) the M/NM-R was significantly better (1/2.43), as was the PN/CN-R (1/1.48) (P < 0.001 in both cases). The specificity was significantly higher in the DD-G and significantly higher for trained examiners as compared with examiners with little training. More that one-third of all melanomas discovered by digital dermoscopy were in situ, and the mean Breslow thickness was 0.32 mm for the invasive ones. CONCLUSIONS: The reduction of unnecessary excisions when using digital dermoscopy compared with dermoscopy alone in our study suggests that access to digital dermoscopy offers a better management of pigmented lesions in daily practice. The high number of early lesions diagnosed by this technique confirms that its use is safe.

[Unusual presentation of scurvy mimicking a neuroblastoma]. / Présentation inhabituelle d'un scorbut faisant craindre un neuroblastome.

Scurvy, a disease related to ascorbic acid deficiency, remains rare in industrial countries. Ascorbic acid is a vitamin that intervenes most notably in the synthesis of collagen and catecholamines. We report the case of a 2-year-old boy hospitalized in a pediatric oncology unit because of an unusual presentation of scurvy revealed by pain and a significant increase in urinary catecholamine levels, raising fear of a neuroblastoma.