Colloid cysts of the third ventricle: correlation of MR and CT findings with histology and chemical analysis.

Eight patients with colloid cysts of the third ventricle were examined with CT and MR. In six, surgical resection was performed and the material was subjected to histologic evaluation; the concentrations of trace elements were determined by particle-induced X-ray emission. Stereotaxic aspiration was performed in two. The investigation showed that colloid cysts are often iso- or hypodense relative to brain on CT (5/8), but sometimes have a center of increased density. Increased density did not correlate with increased concentration of calcium or other metals but did not correlate with high cholesterol content. Colloid cysts appear more heterogeneous on MR (6/8) than on CT (3/8), despite a homogeneous appearance at histology. High signal on short TR/TE sequences is correlated with a high cholesterol content. A marked shortening of the T2 relaxation time is often noticed in the central part of the cyst. Analysis of trace elements showed that this phenomenon is not related to the presence of metals with paramagnetic effects. Our analysis of the contents of colloid cysts does not support the theory that differing metallic concentrations are responsible for differences in MR signal intensity or CT density. We did find that increased CT density and high MR signal correlated with high cholesterol content.

Cryo-electron microscopy of vitreous sections of native biological cells and tissues : methodology and applications

Résumé L'eau est souvent considérée comme une substance ordinaire puisque elle est très commune dans la nature. En fait elle est la plus remarquable de toutes les substances. Sans l'eau la vie sur la terre n'existerait pas. L'eau représente le composant majeur de la cellule vivante, formant typiquement 70 à 95% de la masse cellulaire et elle fournit un environnement à d'innombrables organismes puisque elle couvre 75% de la surface de terre. L'eau est une molécule simple faite de deux atomes d'hydrogène et un atome d'oxygène. Sa petite taille semble en contradiction avec la subtilité de ses propriétés physiques et chimiques. Parmi celles-là, le fait que, au point triple, l'eau liquide est plus dense que la glace est particulièrement remarquable. Malgré son importance particulière dans les sciences de la vie, l'eau est systématiquement éliminée des spécimens biologiques examinés par la microscopie électronique. La raison en est que le haut vide du microscope électronique exige que le spécimen biologique soit solide. Pendant 50 ans la science de la microscopie électronique a adressé ce problème résultant en ce moment en des nombreuses techniques de préparation dont l'usage est courrant. Typiquement ces techniques consistent à fixer l'échantillon (chimiquement ou par congélation), remplacer son contenu d'eau par un plastique doux qui est transformé à un bloc rigide par polymérisation. Le bloc du spécimen est coupé en sections minces (d’environ 50 nm) avec un ultramicrotome à température ambiante. En général, ces techniques introduisent plusieurs artefacts, principalement dû à l'enlèvement d'eau. Afin d'éviter ces artefacts, le spécimen peut être congelé, coupé et observé à basse température. Cependant, l'eau liquide cristallise lors de la congélation, résultant en une importante détérioration. Idéalement, l'eau liquide est solidifiée dans un état vitreux. La vitrification consiste à refroidir l'eau si rapidement que les cristaux de glace n'ont pas de temps de se former. Une percée a eu lieu quand la vitrification d'eau pure a été découverte expérimentalement. Cette découverte a ouvert la voie à la cryo-microscopie des suspensions biologiques en film mince vitrifié. Nous avons travaillé pour étendre la technique aux spécimens épais. Pour ce faire les échantillons biologiques doivent être vitrifiés, cryo-coupées en sections vitreuse et observées dans une cryo-microscope électronique. Cette technique, appelée la cryo- microscopie électronique des sections vitrifiées (CEMOVIS), est maintenant considérée comme étant la meilleure façon de conserver l'ultrastructure de tissus et cellules biologiques dans un état très proche de l'état natif. Récemment, cette technique est devenue une méthode pratique fournissant des résultats excellents. Elle a cependant, des limitations importantes, la plus importante d'entre elles est certainement dû aux artefacts de la coupe. Ces artefacts sont la conséquence de la nature du matériel vitreux et le fait que les sections vitreuses ne peuvent pas flotter sur un liquide comme c'est le cas pour les sections en plastique coupées à température ambiante. Le but de ce travail a été d'améliorer notre compréhension du processus de la coupe et des artefacts de la coupe. Nous avons ainsi trouvé des conditions optimales pour minimiser ou empêcher ces artefacts. Un modèle amélioré du processus de coupe et une redéfinitions des artefacts de coupe sont proposés. Les résultats obtenus sous ces conditions sont présentés et comparés aux résultats obtenus avec les méthodes conventionnelles. Abstract Water is often considered to be an ordinary substance since it is transparent, odourless, tasteless and it is very common in nature. As a matter of fact it can be argued that it is the most remarkable of all substances. Without water life on Earth would not exist. Water is the major component of cells, typically forming 70 to 95% of cellular mass and it provides an environment for innumerable organisms to live in, since it covers 75% of Earth surface. Water is a simple molecule made of two hydrogen atoms and one oxygen atom, H2O. The small size of the molecule stands in contrast with its unique physical and chemical properties. Among those the fact that, at the triple point, liquid water is denser than ice is especially remarkable. Despite its special importance in life science, water is systematically removed from biological specimens investigated by electron microscopy. This is because the high vacuum of the electron microscope requires that the biological specimen is observed in dry conditions. For 50 years the science of electron microscopy has addressed this problem resulting in numerous preparation techniques, presently in routine use. Typically these techniques consist in fixing the sample (chemically or by freezing), replacing its water by plastic which is transformed into rigid block by polymerisation. The block is then cut into thin sections (c. 50 nm) with an ultra-microtome at room temperature. Usually, these techniques introduce several artefacts, most of them due to water removal. In order to avoid these artefacts, the specimen can be frozen, cut and observed at low temperature. However, liquid water crystallizes into ice upon freezing, thus causing severe damage. Ideally, liquid water is solidified into a vitreous state. Vitrification consists in solidifying water so rapidly that ice crystals have no time to form. A breakthrough took place when vitrification of pure water was discovered. Since this discovery, the thin film vitrification method is used with success for the observation of biological suspensions of. small particles. Our work was to extend the method to bulk biological samples that have to be vitrified, cryosectioned into vitreous sections and observed in cryo-electron microscope. This technique is called cryo-electron microscopy of vitreous sections (CEMOVIS). It is now believed to be the best way to preserve the ultrastructure of biological tissues and cells very close to the native state for electron microscopic observation. Since recently, CEMOVIS has become a practical method achieving excellent results. It has, however, some sever limitations, the most important of them certainly being due to cutting artefacts. They are the consequence of the nature of vitreous material and the fact that vitreous sections cannot be floated on a liquid as is the case for plastic sections cut at room temperature. The aim of the present work has been to improve our understanding of the cutting process and of cutting artefacts, thus finding optimal conditions to minimise or prevent these artefacts. An improved model of the cutting process and redefinitions of cutting artefacts are proposed. Results obtained with CEMOVIS under these conditions are presented and compared with results obtained with conventional methods.

The analysis of ecstasy tablets in a forensic drug intelligence perspective

The use by police services and inquiring agencies of forensic data in an intelligence perspective is still fragmentary and to some extent ignored. In order to increase the efficiency of criminal investigation to target illegal drug trafficking organisations and to provide valuable information about their methods, it is necessary to include and interpret objective drug analysis results already during the investigation phase. The value of visual, physical and chemical data of seized ecstasy tablets, as a support for criminal investigation on a strategic and tactical level has been investigated. In a first phase different characteristics of ecstasy tablets have been studied in order to define their relevance, variation, correlation and discriminating power in an intelligence perspective. During 5 years, over 1200 cases of ecstasy seizures (concerning about 150000 seized tablets) coming from different regions of Switzerland (City and Canton of Zurich, Cantons Ticino, Neuchâtel and Geneva) have been systematically recorded. This turned out to be a statistically representative database including large and small cases. During the second phase various comparison and clustering methods have been tested and evaluated, on the type and relevance of tablet characteristics, thus increasing knowledge about synthetic drugs, their manufacturing and trafficking. Finally analytical methodologies have been investigated and formalised, applying traditional intelligence methods. In this context classical tools, which are used in criminal analysis (like the I2 Analyst Notebook, I2 Ibase, ?) have been tested and adapted to address the specific need of forensic drug intelligence. The interpretation of these links provides valuable information about criminal organisations and their trafficking methods. In the final part of this thesis practical examples illustrate the use and value of such information.

Overweight in Swiss children and associations with children's and parents' characteristics et Worldwide trends in childhood obesity

(1) Surpoids chez les enfants suisses et associations avec certaines caractéristiques chez les enfants et leurs parents Le but de cette étude était de mesurer la prévalence du surpoids et de l?obésité chez les enfants de sixième année du canton de Vaud (âge moyen de 12 ans) et les facteurs associés au surpoids. Les données ont été récoltées lors d?une étude menée par l?Institut universitaire de médecine sociale et préventive. Tous les enfants scolarisés en 6ème année à l?école publique du canton de Vaud entre septembre 2005 et mai 2006 étaient éligibles à participer à cette étude. Le taux de participation a atteint 76% (soit 5207 enfants de 12,3 ans en moyenne). Le poids et la taille des enfants ont été mesurés à l?école par des assistants de recherche et les enfants ont rempli, en classe, un questionnaire structuré sur leur mode de vie (notamment : temps quotidien passé à regarder la télévision, à jouer à des jeux sur écran; fréquence de la pratique de diverses activités physiques; fréquence de la consommation de fruits ou de légumes). Des informations sur les parents (niveau d?éducation, nationalité, poids et taille) ont été récoltées au moyen d?un questionnaire structuré envoyé par courrier à ceux-ci. Nous avons utilisé les critères de l?International Obesity Task Force, qui définit les valeurs-seuils de l'indice de masse corporelle pour le surpoids et pour l?obésité, par age et par sexe. La prévalence du surpoids (obésité incluse) dans la population était de 15% chez les garçons et de 12% chez les filles, et la prévalence de l?obésité était de 2% dans les deux sexes. Nous avons trouvé que le surpoids était associé de façon indépendante avec le temps passé à regarder la télévision, ainsi qu?avec certaines caractéristiques des parents, comme le surpoids, un bas niveau d?éducation et une nationalité étrangère. En conclusion, un enfant sur sept est en surpoids ou obèse dans le canton de Vaud. Ces chiffres indiquent un important défi de santé publique, même si cette prévalence dans le canton de Vaud est, actuellement, moindre que dans beaucoup d?autres pays d?Europe, et bien moindre qu?en Amérique du Nord. Les associations entre le surpoids infantile et le temps passé à regarder la télévision, ainsi que les associations avec des variables liées au milieu socio-culturel des parents indiquent plusieurs pistes d?intervention pour prévenir le surpoids chez les enfants. Il est probable que les mesures de prévention ne devraient pas se limiter aux approches individuelles, mais devraient aussi inclure des mesures structurelles sur l?environnement social, physique et économique visant à réduire les facteurs obésogènes dans la société.<br/><br/>Objective: The objective was to assess the prevalence of overweight and obesity in children in a canton of Switzerland and the association with various characteristics of the parents and the children. Research Methods and Procedures: A cross-sectional survey was conducted in all children of the sixth school grade of the canton of Vaud, Switzerland. Weight and height were measured, and selected lifestyle variables were assessed with a self-administered semiquantitative questionnaire. Information on children?s parents was gathered through a mailed structured questionnaire. Overweight and obesity were based on the International Obesity Task Force criteria. Results: Of 6873 eligible children, 5207 (76%) participated (2621 boys, 2586 girls; mean age, 12.3 years; standard deviation, 0.5 year). The prevalence of overweight (including obesity) was 15.0% (95% confidence interval, 13.7% to 16.4%) in boys and 12.4% (11.1% to 13.7%) in girls, and the prevalence of obesity was 1.8% (1.3% to 2.3%) and 1.7% (1.2% to 2.2%), respectively. In both univariate and multivariate analyses, overweight was strongly associated with high television viewing time and selected characteristics of the parents (overweight, low educational level, and foreign nationality). Discussion: The prevalence of pediatric overweight and obesity was lower in this region of Switzerland than in several European countries. The correlates of overweight found in this region suggest areas for potential interventions.

Effects of DMPP on the growth and chemical composition of ryegrass (Lolium perenne L.) raised on calcareous soil

Se llevó a cabo un experimento de 406 días en macetas para evaluar el nuevo inhibidor de la nitrificación, 3,4-dimetilpirazol fosfato (DMPP), añadido a purines de cerdo. Se utilizaron macetas que contenían tierra franca calcárea que fueron sujetas a los siguientes tratamientos: sin purín, 73,7; 147,3 y 221 cm3 de purín por maceta, todas con o sin tratamiento de DMPP. A los 18 días las macetas fueron sembradas con Lolium perenne L. El mayor rendimiento (36,3 g maceta-1) se obtuvo para el tratamiento con la dosis superior de purín y DMPP, siendo un 7,4% superior al mismo tratamiento sin inhibidor y un 46,1% superior al tratamiento control. Las plantas tratadas con dosis alta y mediana, más el DMPP, absorbieron el 70% del total del N durante la primera fase del experimento (104 días) mientras que sin inhibidor absorbieron el 55,3 y el 62% respectivamente. Se observó una reducción significativa del 17% en el N lixiviado en los tratamientos sin cultivo al aplicar DMPP. El inhibidor aumentó significativamente la eficiencia agronómica del purín (g materia seca g-1 N aplicado).

Yield formation and quality characteristics of early potatoes during a short growing period

Selostus: Typpilannoituksen ja nostoajankohdan vaikutus varhaisperunan satoon

Is high dose rate brachytherapy reliable and effective treatment for prostate cancer patients? A review of the literature.

The intrinsic physical and radiobiological characteristics of High Dose Rate Brachytherapy (HDR-BT) are well suited to the treatment of prostate cancer. HDR-BT was initially used as a boost to external beam brachytherapy, but has subsequently been employed as the sole treatment, which is termed HDR monotherapy. This review summarizes the clinical outcomes and toxicity results of the principal studies and discusses the radiobiological basis supporting its use.

The contribution of individual and professional characteristics to general and work-related well-being

Cette thèse porte sur la contribution des caractéristiques individuelles et des situations professionnelles au bien-être. En combinant différentes perspectives théoriques, notamment la théorie de la construction de la carrière, la théorie de la justice organisationnelle, les modèles du bien-être au travail, et les conceptualisations de l'incivilité au travail, un certain nombre d'hypothèses sont proposées concernant le lien entre certaines caractéristiques individuelles et situationnelles et le bien-être général et professionnel. Les deux premières études se focalisent sur la validation d'une échelle d'adaptabilités de carrière et sur le rôle médiateur de cette adaptabilité dans la relation entre des dispositions et le bien-être. La troisième étude évolue l'hypothèse d'un possible effet de médiation de l'adaptabilité mais cette fois de la relation entre insécurité professionnelle et charge de travail d'une part et le bien-être d'autre part. La quatrième étude adopte une perspective longitudinale et analyse les associations entre les dimensions de la personnalité, l'adaptabilité de carrière et le bien-être dans quatre parcours professionnels différents. La cinquième étude porte sur une autre caractéristique individuelle, à savoir la croyance en un monde juste. Cette étude illustre comment la croyance en un monde juste influence les perceptions de justice organisationnelle une année après, qui ont une incidence importante sur le bien-être. Enfin, la dernière étude se concentre sur une population spécifique, les immigrants en Suisse, et souligne qu'être la cible d'incivilité sur le lieu de travail est généralement liée au pays d'origine. Globalement, cette thèse met en évidence que les caractéristiques individuelles ont des effets tant directs qu'indirects sur le bien-être et que ces mêmes caractéristiques explique en partie, les relations entre la situation professionnelle et le bien-être. Plus spécifiquement, des situations professionnelles peuvent influencer l'expression de certaines caractéristiques individuelles, soit en contribuant à leurs activations ou à leurs inhibitions. De plus, l'impact des caractéristiques individuelles sur le bien-être semble dépendre de la situation professionnelle. Il est donc important de considérer les influences simultanées et réciproques des caractéristiques individuelles et de la situation contextuelle et professionnelle pour rendre compte du bien-être général et professionnel. -- This thesis explores how individual characteristics and professional situations correspond to well-being. Drawing from various theoretical backgrounds, such as career construction theory, justice theory, models of job strain, and theories on subtle discrimination, a number of specific hypotheses are put forward pertaining to a selection of individual and professional aspects as well as general and work-related well-being. The six studies presented in this thesis focus on specific aspects and adopt different methodological and theoretical approaches. The first two studies concern the validation of the career adapt-abilities scale and test the potential of career adapt-abilities to mediate the relationship between dispositions and outcomes. The third study extends the hypothesis of career adapt-abilities as a mediator and finds that it mediates the effects of job insecurity and job strain on general and professional well-being. The fourth study adopts a longitudinal approach and tests the associations between personality traits and career adaptability and well-being in four different professional situations. Study five concerns another individual characteristic, belief in a just world, and illustrates how justice beliefs drive perceptions of organizational justice, which in turn impact, on well-being outcomes one year later. The final study focuses on the professional experiences of a specific population, immigrants in Switzerland, and confirms that being a target of incivilities is related to national origin. Globally, this thesis finds that individual characteristics have direct and indirect influences on well-being and that these characteristics may also mediate the associations between professional situations and outcomes. In particular, the professional situation may alter the display of individual characteristics, either by contributing to their activation or their depletion, and the ways in which individual factors influence well-being does seem to depend on the professional situation. It is thus necessary to adopt a "both...and" perspective when studying the impact of individual and professional characteristics as these factors mutually influence each other.

Type 1 diabetes mellitus in people with pharmacoresistant epilepsy: Prevalence and clinical characteristics.

BACKGROUND: There have been inconsistent reports on the potential association between diabetes mellitus and epilepsy. METHODS: We examined a consecutive cohort of 2016 people with pharmacoresistant epilepsy admitted to a tertiary medical centre. RESULTS: We identified 20 individuals with type 1 diabetes mellitus (T1DM); a point prevalence of 9.9 (95% CI: 6.4, 15.3) cases per 1000 individuals. This represents a more than two-fold increase relative to published prevalence estimates of T1DM in the general population. The onset of T1DM preceded that of epilepsy in 80% of individuals, by a median of 1.5 years. Individuals with T1DM were significantly more likely to have cryptogenic/unknown epilepsy relative to those with type 2 diabetes mellitus or without diabetes (85% versus 35% and 49%, p=0.045). All individuals with T1DM had focal epilepsy, the majority of which were temporal lobe in origin, although there was no evidence that this proportion was any different from those without T1DM (p>0.999). CONCLUSIONS: The prevalence of T1DM appears to be increased in people with pharmacoresistant epilepsy and is associated with cryptogenic/unknown epilepsy. These findings may have pathophysiological implications, especially in the context of anti-glutamic acid decarboxylase antibodies.

Phenotypic and genotypic characteristics of cryopyrin-associated periodic syndrome: a series of 136 patients from the Eurofever Registry.

OBJECTIVE: To evaluate genetic, demographic and clinical features in patients with cryopyrin-associated periodic syndrome (CAPS) from the Eurofever Registry, with a focus on genotype-phenotype correlations and predictive disease severity markers. METHODS: A web-based registry retrospectively collected data on patients with CAPS. Experts in the disease independently validated all cases. Patients carrying NLRP3 variants and germline-mutation-negative patients were included. RESULTS: 136 patients were analysed. The median age at disease onset was 9 months, and the median duration of follow-up was 15 years. Skin rash, musculoskeletal involvement and fever were the most prevalent features. Neurological involvement (including severe complications) was noted in 40% and 12% of the patients, respectively, with ophthalmological involvement in 71%, and neurosensory hearing loss in 42%. 133 patients carried a heterozygous, germline mutation, and 3 patients were mutation-negative (despite complete NLRP3 gene screening). Thirty-one different NLRP3 mutations were recorded; 7 accounted for 78% of the patients, whereas 24 rare variants were found in 27 cases. The latter were significantly associated with early disease onset, neurological complications (including severe complications) and severe musculoskeletal involvement. The T348M variant was associated with early disease onset, chronic course and hearing loss. Neurological involvement was less strongly associated with V198M, E311 K and A439 V alleles. Early onset was predictive of severe neurological complications and hearing loss. CONCLUSIONS: Patients carrying rare NLRP3 variants are at risk of severe CAPS; onset before the age of 6 months is associated with more severe neurological involvement and hearing loss. These findings may have an impact on treatment decisions.

Effects of Enriched Physical and Social Environments on Motor Performance, Associative Learning, and Hippocampal Neurogenesis in Mice.

We have studied the motor abilities and associative learning capabilities of adult mice placed in different enriched environments. Three-month-old animals were maintained for a month alone (AL), alone in a physically enriched environment (PHY), and, finally, in groups in the absence (SO) or presence (SOPHY) of an enriched environment. The animals' capabilities were subsequently checked in the rotarod test, and for classical and instrumental learning. The PHY and SOPHY groups presented better performances in the rotarod test and in the acquisition of the instrumental learning task. In contrast, no significant differences between groups were observed for classical eyeblink conditioning. The four groups presented similar increases in the strength of field EPSPs (fEPSPs) evoked at the hippocampal CA3-CA1 synapse across classical conditioning sessions, with no significant differences between groups. These trained animals were pulse-injected with bromodeoxyuridine (BrdU) to determine hippocampal neurogenesis. No significant differences were found in the number of NeuN/BrdU double-labeled neurons. We repeated the same BrdU study in one-month-old mice raised for an additional month in the above-mentioned four different environments. These animals were not submitted to rotarod or conditioned tests. Non-trained PHY and SOPHY groups presented more neurogenesis than the other two groups. Thus, neurogenesis seems to be related to physical enrichment at early ages, but not to learning acquisition in adult mice.

Harmonization of training and assessment of medical specialists in physical and rehabilitation medicine across Europe - The contribution of the UEMS Board of Physical and Rehabilitation Medicine

Background.- The main goals of the European Board of Physical and Rehabili-tation Medicine (EBPRM), founded in 1991 as the third speciality board of theUnion of European Medical Specialists (UEMS), are to harmonize pre-graduate,post-graduate and continuous medical education in physical and rehabilitationmedicine (PRM) all over Europe. The harmonization of curricula of the medi-cal specialities and the assessment of medical specialists has become one of thepriorities of the UEMS and its working groups to which the EBPRM contributes.Action.- The EBPRM will continue to promote a specific minimal undergraduatecurriculum on PRM including issues like disability, participation and handicapto be taught all over Europe as a basis for general medical practice. The EBPRMwill also expand the existing EBPRM postgraduate curriculum into a detailedcatalogue of learning objectives. This catalogue will serve as a tool to boostharmonization of the national curricula across Europe as well as to structurethe content of the MCQ examination. It would be a big step forward towardsharmonization of European PRM specialist training if an important number ofcountries would use the certifying MCQ examination of the Board as a part ofthe national assessments for PRM specialists.

Educational resources offered by the European Board of Physical and Rehabilitation Medicine (EBPRM)

Background .- Physical and Rehabilitation Medicine (PRM) is a very demanding medical speciality. To ensure high standard of research and care in PRM all across Europe, it is crucial to attract gifted trainees and offer them high quality education. At undergraduate level, many medical schools in Europe omit to offer teaching on disabled persons and on basic PRM knowledge. Thus PRM is hardly known to medical students. For postgraduate trainees access to evidence-based knowledge as well as teaching of research methodology specific to PRM, rehabilitation methodology, disability management and team building also need to be strengthened to increase the visibility of PRM. Action .- To address these issues the EBPRM proposes presently a specific undergraduate curriculum in PRM including the issues of disability, participation and handicap as a basis for general medical practice and postgraduate rehabilitation training. For PRM trainees many educational documents are now available on the EBPRM website. A growing number of educational sessions for PRM trainees take place during international and national PRM Congresses which can be accessed at low cost. Educational papers published regularly in European rehabilitation journals and European PRM Schools are offered free or at very low cost to trainees.

A retrospective study of deep sternal wound infections: clinical and microbiological characteristics, treatment, and risk factors for complications.

Deep sternal wound infection (DSWI) is a feared complication following cardiac surgery. This study describes clinical, microbiological, and treatment outcomes of DSWI and determines risk factors for complications. Of 55 patients with DSWI, 66% were male and mean age was 68.2years. Initial sternotomy was for coronary artery bypass graft in 49% of patients. Sternal debridement at mean 25.4±18.3days showed monomicrobial (94%), mainly Gram-positive infection. Secondary sternal wound infection (SSWI) occurred in 31% of patients, was mostly polymicrobial (71%), and was predominantly due to Gram-negative bacilli. Risk factors for SSWI were at least 1 revision surgery (odds ratio [OR] 4.8 [95% confidence interval {CI} 1.0-22.4], P=0.047), sternal closure by muscle flap (OR 4.6 [1.3-16.8], P=0.02), delayed sternal closure (mean 27 versus 14days, P=0.03), and use of vacuum-assisted closure device (100% versus 58%, P=0.008). Hospital stay was significantly longer in patients with SSWI (69days versus 48days, P=0.04).

Under what conditions? Therapist and client characteristics moderate the role of change talk in brief motivational intervention.

OBJECTIVE: Client change talk has been proposed as a mechanism of change in motivational interviewing (MI) by mediating the link between therapist MI-consistent behaviors (MICO) and client behavioral outcomes. We tested under what circumstances this mechanism was supported in the context of a clinical trial of brief MI for heavy drinking among nontreatment seeking young men. METHOD: We conducted psycholinguistic coding of 174 sessions using the MI Skill Code 2.1 and derived the frequency of MICO and the strength of change talk (CTS) averaged over the session. CTS was examined as a mediator of the relationship between MICO and a drinking composite score measured at 3-month follow-up, controlling for the composite measure at baseline. Finally, we tested therapist gender and MI experience as well as client readiness to change and alcohol problem severity as moderators of this mediation model. RESULTS: CTS significantly predicted outcome (higher strength related to less drinking), but MICO did not predict CTS. However, CTS mediated the relationship between MICO and drinking outcomes when therapists had more experience in MI and when clients had more severe alcohol problems (i.e., significant conditional indirect effects). CONCLUSIONS: The mechanism hypothesized by MI theory was operative in our brief MI with heavy drinking young men, but only under particular conditions. Our results suggest that attention should be paid to therapist selection, training, and/or supervision until they reach a certain level of competence, and that MI might not be appropriate for nontreatment seeking clients drinking at a lower level of risk. (PsycINFO Database Record