Dendron based antifouling, MRI and magnetic hyperthermia properties of different shaped iron oxide nanoparticles.

Owing to the great potential of iron oxide nanoparticles (NPs) for nanomedicine, large efforts have been made to better control their magnetic properties, especially their magnetic anisotropy to provide NPs able to combine imaging by MRI and therapy by magnetic hyperthermia. In that context, the design of anisotropic NPs appears as a very promising and efficient strategy. Furthermore, their bioactive coating also remains a challenge as it should provide colloidal stability, biocompatibility, furtivity along with good water diffusion for MRI. By taking advantage of our controlled synthesis method of iron oxide NPs with different shapes (cubic, spherical, octopod and nanoplate), we demonstrate here that the dendron coating, shown previously to be very suitable for 10 nm sized iron oxide, also provided very good colloidal, MRI and antifouling properties to the anisotropic shaped NPs. These antifouling properties, demonstrated through several experiments and characterizations, are very promising to achieve specific targeting of disease tissues without affecting healthy organs. On the other hand, the magnetic hyperthermia properties were shown to depend on the saturation magnetization and the ability of NPs to self-align, confirming the need of a balance between crystalline and dipolar magnetic anisotropies.

3T tractography of the median nerve: optimisation of acquisition parameters and normative diffusion values.

PURPOSE: To define the optimal acquisition parameters for diffusion tensor imaging of the median nerve at the wrist and to measure the diffusion values. PATIENTS AND METHODS: The wrists of 14 healthy volunteers were explored using 3T MRI with a dedicated wrist coil. Each examination consisted of six sequences, varying the number of directions (15-20-30) and the b values (500-800-1000-2000s/mm(2)). The tractography images were evaluated by two radiologists using a qualitative scale with six levels. The diffusion and anisotropy coefficients (ADC and FA) were measured and the values compared with the data in the literature. RESULTS: Median nerve tractography was successfully achieved in all sequences. The 20 direction sequence with b=1000s/mm(2) seemed to provide the best results for a reasonable acquisition time (5'38″). The diffusion values showed large interindividual variations. CONCLUSION: Optimisation of acquisitions parameters is important in peripheral nerve tractography, and may facilitate a routine use of the technique. The images obtained are easy to analyse but the diffusivity and anisotropy coefficients are too variable, however, to be used in practice.

Scaphotrapezial ligament: normal arthro-CT and arthro-MRI appearance with anatomical and clinical correlation.

The purpose of our study was to demonstrate and describe the MR and arthro-CT anatomic appearance of the scaphotrapezial ligament and illustrate some of the pathologies involving this structure. This ligament consists of two slips that originate from the radiopalmar aspect of the scaphoid tuberosity and extend distally, forming a V shape. The ulnar fibers, which are just radial to the flexor carpi radialis sheath, inserted along the trapezial ridge. The radial fibers were found to be thinner and inserted at the radial aspect of the trapezium. Twelve fresh cadaver wrists were dissected, with close attention paid to the scaphotrapezio-trapezoidal (STT) joint. An osseoligamentous specimen was dissected with removal of all musculotendinous structures around the STT joint and was performed with high-resolution acquisition in a 128-MDCT scanner. Samples of the wrist area were collected from two fetal specimens. A retrospective study of 55 patients with wrist pain that were submitted to arthrography, arthro-CT, and arthro-MRI imaging was performed (10 patients on a 3-T superconducting magnet and 45 patients on a 1.5-T system). Another ten patients had high-resolution images on a 3-T superconducting magnet without arthrographic injection. MR arthrography and arthro-CT improved visualization and provided detailed information about the anatomy of the scaphotrapezial ligament. Knowledge of the appearance of this normal ligament on MRI allows accurate diagnosis of lesions and will aid when surgery is indicated or may have a role in avoiding unnecessary immobilization.

Development of specific social skills training programmes for schizophrenia patients: results of a multicentre study.

OBJECTIVE: The efficacy of three newly developed cognitive social skills training programmes for residential, vocational and recreational functioning (experimental groups) were compared with a traditional social skills training programme (control group) referring to cognitive and social abilities, psychopathology and generalisation effects. METHOD: One hundred and five patients with a diagnosis of schizophrenia or schizoaffective disorder according to ICD-10 criteria were selected and assigned to the different treatment groups, using a matching procedure. The treatment phase lasted 6 months. A follow-up assessment was carried out after 1 year. RESULTS: Higher global therapy effects were obtained on almost all dependent variables in the experimental groups. Analyses of variance and covariance indicated higher symptom reduction for the experimental groups, but significantly greater improvements in some cognitive variables for the control group. Correlation analysis suggested associations between improvement of social behaviour with symptom reduction and improvements of cognitive skills. CONCLUSION: In view of these favourable effects, the developed cognitive social skills training programmes might facilitate the abilities of schizophrenia patients for their integration in the community.

Improving recreational, residential, and vocational outcomes for patients with schizophrenia.

As Roder and colleagues propose, we have seen three eras in the development and refinement of social skills training for individuals with schizophrenia. In the 1960s, skills training relied on the use of operant conditioning, as exemplified by the token economy. Reinforcement contingencies succeeded in activating patients with negative symptoms and in improving their social behavior. Contemporary psychiatric rehabilitation can profit from the identification and use of reinforcers to motivate anergic individuals who lack insight to participate actively in community-based programs. During the second era, in the 1970s, social learning through modeling, coaching, role playing, and behavioral assignments was introduced into skills training. These techniques were used to improve nonverbal skills, such as eye contact, fluency of speech, gestures, and facial expression, as well as conversational skills, assertiveness, and emotional expressiveness. Intervention programs of the third and current era are incorporating cognitive methods into the skills training enterprise. For example, in the modules for training social and independent living skills developed and validated by Liberman and his colleagues at the University of California at Los Angeles (1), the deficits in attention, memory, and verbal learning often experienced by persons with schizophrenia are overcome by repetition, shaping of incremental behavioral improvements, video modeling, and feedback for galvanizing attention. Procedural learning techniques that do not rely on the brain capacities that mediate verbal awareness and insight are also used. In this month's Rehab Rounds column, Roder and his colleagues present another example of a skills training approach of the third era that includes elements of cognitive remediation. As autonomous offsprings of integrated psychological therapy (IPT), which was originally developed by Hans Brenner and Volker Roder and their colleagues at the University of Bern in Switzerland (2), the new programs address deficits in the residential, vocational, and recreational domains of community functioning. Overall, social skills training has been shown to be effective in the acquisition and maintenance of skills and their transfer to community life. Moreover, evidence is accumulating that structured and systematic skills training is more effective than other psychosocial treatments with which it has been compared, such as supportive group therapy and expressive modes of occupational therapy.

[Effects of new cognitive-behavioral therapy programs for improvement of specific social skills of schizophrenics--a controlled study]. / Effekte neuer kognitiv-behavioraler Therapieprogramme zur Verbesserung spezifischer sozialer Fertigkeiten bei schizophren Erkrankten. Eine kontrollierte Studie.

Based on the Integrated Psychological Therapy (IPT) for schizophrenia patients, the Berne group developed three specific cognitive behaviour therapy programmes for treating residential, vocational, and recreational functioning. We added new cognitive-emotional methods to these programmes that were devised especially for schizophrenia patients, taking into consideration the criticism of traditional social skill training methods. In the present multicentre study, these new programmes (experimental group) were compared with a traditional social skills training programme (control group, IPT "Social Skills" subprogramme). Both the therapy and aftercare phase each lasted 12 weeks and the follow-up phase 1 year. Assessment instruments covered psychopathology, cognitive functioning, and social adjustment. Higher ratings of global treatment effects and significant reductions in symptoms were obtained in the experimental group. In view of the favourable results, these newly designed social skill training programmes may replace more conventional therapy approaches in the future.

Validation of bone conversion in osteoconductive and osteoinductive bone substitutes.

Bone reconstruction can be performed with an autogeneic graft from various donor regions. Osteoconductive and osteoinductive bone substitutes originate from substances of diverse chemical and morphological types and can have a synthetic or a biological derivation. Alongside autogeneic bone transplants and allogenic and xenogeneic bone implants, alloplastic bone replacements of synthetic or semi-synthetic origin are being used for defect reconstruction. In an animal model in rabbits five bone substitutes and one autogeneic graft were surgically incorporated into identical bone defects (10times 10 mm in size) in six anatomically defined regions of the skull. With scintigraphic and histological methods, the metabolic dynamics of the bone is examined as it reacts to the transplantation of autogeneic bone or to implanted bone replacement material.The different autogeneic, xenogeneic and alloplastic bone replacement materials can be differentiated according to the functional quality of the new tissue and the dynamics of the bone conversion thus induced. In the comparison of mineralized, osteoconductive bone subsitutes (TCP, HA, calcium carbonate ceramics) with demineralized, osteoinductive implants (DBM new, DBM old) and autogeneic bone grafts, the bone inducing matrices show the largest quantity of new bone formation, making possible a volume-constant reconstruction.

Brown-Sequard syndrome following cervical spine compression fracture.

Brown-Sequard Syndrome is most commonly caused by penetrating trauma to the spinal cord. The case of a 15-year-old male who developed Brown-Sequard Syndrome following blunt cervical spine trauma sustained in an automobile accident is presented. Brown-Sequard Syndrome is rarely seen following blunt trauma; however, one must be suspicious so as not to overlook this type of lesion.

Capitalization, population movement, and the local public sector: a probabilistic analysis.

PIP: Using data collected from household interviews in a 1965 San Francisco Bay Area Transportation Study, a probabilistic model is developed to explain the relationship between population movement and the capitalization of changes in the public sector in the price of housing. This model is constructed to compare 2 competing explanations for the flight of higher income households to the suburbs: 1) the accessibility model and 2) the flight from blight model. The accessibility model explains the decay of cities as a natural outgrowth of decreasing transportation costs, whereas the flight from blight model suggests that the wealthy leave the central city for the suburbs because of urban decay. An analysis of the San Francisco data demonstrates that high income households are more sensitive than the rest of the population to changes in the median income of the neighborhood and in expenditures and general government and education, but less sensitive to changes in property tax rate and expenditures on public safety, parks, and recreation. It is unlikely that undesirable changes in the public sector will result in a mass exodus of higher income households; capitalization in the price of housing appears sufficient to prevent this. The 2 models combined help explain the flight from the central cities, while the combined variables increase the logit estimation's prediction of bids for housing.^ieng