The most accurate results were achieved with two configurations: (1) the optical intraoral system with powder and (2) the open technique with splinted squared transfer copings, using polyether as impression material.

The design and production of structures with nanometer-sized polymer films based on layer-by-layer (LbL) are of particular interest for tissue engineering since they allow the precise control of physical and biochemical cues of implantable devices. In this work, a method is developed for the preparation of nanostructured hollow multilayers tubes combining LbL and template leaching. The aim is to produce hollow tubes based on polyelectrolyte multilayer films with tuned physical-chemical properties and study their effects on cell behavior. The final tubular structures are characterized by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), microscopy, swelling, and mechanical tests, including dynamic mechanical analysis (DMA) in physiological simulated conditions. It is found that more robust films could be produced upon chemical cross-linking with genipin. In particular, the mechanical properties confirms the viscoelastic properties and a storage and young modulus about two times higher. The water uptake decreases from about 390% to 110% after the cross-linking. The biological performance is assessed in terms of cell adhesion, viability, and proliferation. The results obtained with the cross-linked tubes demonstrate that these are more suitable structures for cell adhesion and spreading. The results suggest the potential of these structures to boost the development of innovative tubular structures for tissue engineering approaches.

In 1998 we determined in vivo and in vitro the frequency and the degree of resistance of Plasmodium falciparum to the three antimalarials (chloroquine, amodiaquine, and sulfadoxine/pyrimethamine) most utilized in the municipality of Turbo (in the area of Urabá, Antioquia, Colombia), in a sample representative of the population with malaria. We carried out clinical and parasitological analyses over a 14-day period using the standard test recommended by the World Health Organization. In vivo, P. falciparum showed resistance to chloroquine, amodiaquine, and sulfadoxine/pyrimethamine, with a frequency of 97%, 7%, and 13%, respectively. In vitro, the corresponding figures were 21%, 23%, and 9%, respectively. For chloroquine the level of agreement between the in vivo and in vitro results was 23%.

Medical adhesives and sealants often require that long-term adhesiveness is achieved. In this work, nanostructured coatings consisting of chitosan and the adhesive bacterial exopolysaccharide levan are fabricated using layer-by-layer (LbL) assembly. Taking advantage of the electrostatic self-assembly mechanism of LbL, the charges of both chitosan and a phosphonate-derivatized levan (Ph-levan) are measured and the feasibility of constructing hybrid films is monitored and confirmed using a quartz crystal microbalance with dissipation monitoring (QCM-D). The adhesive properties between two identical bonded films with a total of 100 layers are compared to control films in which Ph-levan is replaced by alginate, revealing that the detachment force of the former is about 3 times higher than the control. Scanning electron microscopy of the films surface shows that the surface of Ph-levan films is smooth and homogeneous. Cell adhesion tests were conducted using a L929 cell line. Early cell adhesion is significantly higher in chitosan/Ph-levan films when compared to chitosan/alginate controls.These findings establish levan derivatives as bioinspired ingredients for conceiving medical adhesive devices that allow achieving enhanced mechanical and biological performance.

No abstract

DISCLAIMER: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our subscribers we are providing this early version of the article. The paper will be copy edited and typeset, and proof will be reviewed before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to The Journal pertain.All press releases and the articles they feature are under strict embargo until uncorrected proof of the article becomes available online. We will provide journalists and editors with full-text copies of the articles in question prior to the embargo date so that stories can be adequately researched and written. The standard embargo time is 12:01 AM ET on that date. Materials and Methods:Six anesthetized female pigs underwent ureterorenoscopies in order to place a catheter with an EMT sensor into the desired puncture site and to ascertain the success of puncture. Subsequently, a tracked needle with a similar EMT sensor was navigated into the sensor inside the catheter. Four punctures were performed by two surgeons in each pig: one in the kidney and one in the middle ureter, on both right and left pig sides. Number of attempts and time needed to evaluate the virtual trajectory and to perform the percutaneous puncture were outcomes measurements. Results:Overall 24 punctures were easily performed without any complications.Surgeons required more time to evaluate the trajectory during ureteral puncture than kidney (median 15 versus 13 seconds, range 14 to 18 and 11 to 16 seconds, respectively; p= 0.1). The median renal and ureteral puncture time were 19 and 51 seconds respectively (range 14 to 45 and 45 to 67; p=0.003). Two attempts were needed to achieve a successful ureteral puncture. The presented technique demands presence of renal stone for testing. Conclusions:The proposed EMT solution for renal collecting system puncture proved to be highly accurate, simple and quicker. This method might represent a paradigm shift in percutaneous kidney access techniques.

A novel semi-automatic algorithm for aortic valve (AV) wall segmentation is presented for 3D transesophageal echocardiography (TEE) datasets. The proposed methodology uses a 3D cylindrical formulation of the B-spline Explicit Active Surfaces (BEAS) framework in a dual-stage energy evolution process, comprising a threshold-based and a localized region-based stage. Hereto, intensity and shape-based features are combined to accurately delineate the AV wall from the ascending aorta (AA) to the left ventricular outflow tract (LVOT). Shape-prior information is included using a profile-based statistical shape model (SSM), and embedded in BEAS through two novel regularization terms: one confining the segmented AV profiles to shapes seen in the SSM (hard regularization) and another penalizing according to the profile's degree of likelihood (soft regularization). The proposed energy functional takes thus advantage of the intensity data in regions with strong image content, while complementing it with shape knowledge in regions with nearly absent image data. The proposed algorithm has been validated in 20 3D-TEE datasets with both stenotic and non-stenotic valves. It was shown to be accurate, robust and computationally efficient, taking less than 1 second to segment the AV wall from the AA to the LVOT with an average accuracy of 0.78 mm. Semi-automatically extracted measurements at four relevant anatomical levels (LVOT, aortic annulus, sinuses of Valsalva and sinotubular junction) showed an excellent agreement with experts' ones, with a higher reproducibility than manually-extracted measures.

a b s t r a c tIn order to ensure the precision of the measurement of complex 3D object surfaces using non-contact laser scanning systems, a novel stereo vision calibration procedure based on a laser line projection plane is presented. This calibration procedure can also be used in measurement systems based on a single camera and a laser line projection. This procedure, while using only laser-coplanar points, is oriented towards laser line detection and allows the matching of two images on the laser projection plane without the use of a rigid motion equation. These features make this procedure very precise, simple and, consequently, easier to implement.