Search results for "Note"
showing 10 items of 10709 documents
Total synthesis and biological evaluation of the natural product (−)-cyclonerodiol, a new inhibitor of IL-4 signaling
2014
In a screening program of natural compounds from fungi, the known cyclopentanoid sesquiterpene (-)-cyclonerodiol was identified as a specific inhibitor of the IL-4 induced STAT6 signaling pathway (IC50 = 9.7 μM) which is required for the differentiation of naive CD4 T cells to T helper type 2 (Th2) lymphocytes. As many allergic conditions, including allergic asthma and atopic diseases, are driven by an excessive Th2 response, STAT6 is a promising target for the development of new therapeutics. The compound was synthesized in six steps from (-)-linalool using an epoxide radical cyclization as the key step.
Optimization design process of a morphing winglet
2018
Aeronautic and aerospace engineering is recently moving in the direction of developing morphing wing devices, with the aim of making adaptable the aerodynamic shapes to different operational conditions. Those devices may be classified according to two different conceptual architectures: kinematic or compliant systems. Both of them embed within their body all the active components (actuators and sensors), necessary to their operations. In the first case, the geometry variation is achieved through an augmented classical mechanism, while in the second case the form modification is due to a special arrangement of the inner structure creating a distributed elastic hinges arrangement. Whatever is…
Virtual reality system for planning minimally invasive neurosurgery
2008
Object The authors report on their experience with a 3D virtual reality system for planning minimally invasive neurosurgical procedures. Methods Between October 2002 and April 2006, the authors used the Dextroscope (Volume Interactions, Ltd.) to plan neurosurgical procedures in 106 patients, including 100 with intracranial and 6 with spinal lesions. The planning was performed 1 to 3 days preoperatively, and in 12 cases, 3D prints of the planning procedure were taken into the operating room. A questionnaire was completed by the neurosurgeon after the planning procedure. Results After a short period of acclimatization, the system proved easy to operate and is currently used routinely for pre…
Autostereoscopic Three-Dimensional Neuronavigation to the Sella: Technical Note.
2017
Background A drawback of conventional neuronavigation is the necessity of focusing on two-dimensional images in 3 planes at the same time to determine one's position in the operating field. A solution would be to merge the images into a single three-dimensional (3D) image that mirrors the actual anatomy. The introduction of holographic glassless 3D monitors paved the way to 3D navigation. We present our experience with 3D neuronavigation as exemplified by navigation to and within the sella. Methods Operative planning was conducted with a navigation system using cranial computed tomography and magnetic resonance imaging. The image data sets were processed by the prototype Clariti 3D system t…
Adenosine monophosphate-capped gold(i) nanoclusters: synthesis and lanthanide ion-induced enhancement of their luminescence
2016
Reduction of Au3+ in the presence of just adenosine 5′-monophosphate (AMP) and a zwitterionic organic chemical buffering agent, specifically 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), combined with light exposure, gives rise to luminescent, water-soluble Au+ nanoclusters (Au+ NCs). The photoluminescence of these NCs is considerably enhanced by adding Y3+ or the chemically similar Yb3+ lanthanide that leads to Au+/Y3+ and Au+/Yb3+ NCs, respectively. These NCs are characterised by absorption (steady-state), photoluminescence (steady-state and time-resolved), and X-ray photoelectron spectroscopy.
Label-Free Pyrophosphate Recognition with Functionalized Asymmetric Nanopores
2016
[EN] The label¿free detection of pyrophosphate (PPi) anions with a nanofluidic sensing device based on asymmetric nanopores is demonstrated. The pore surface is functionalized with zinc complexes based on two di(2¿picolyl)amine [bis(DPA)] moieties using carbodiimide coupling chemistry. The complexation of zinc (Zn2+) ion is achieved by exposing the modified pore to a solution of zinc chloride to form bis(Zn2+¿DPA) complexes. The chemical functionalization is demonstrated by recording the changes in the observed current¿voltage (I¿V) curves before and after pore modification. The bis(Zn2+¿DPA) complexes on the pore walls serve as recognition sites for pyrophosphate anion. The experimental re…
Diversity in Itraconazole Cocrystals with Aliphatic Dicarboxylic Acids of Varying Chain Length
2013
The cocrystal formation potential of itraconazole, a potent antifungal drug, with C2–C10 aliphatic dicarboxylic acids has been investigated. Using two experimental screening techniques (solvent-assisted grinding and evaporation-based crystallization), the cocrystals of itraconazole with C2–C7 dicarboxylic acids have been successfully synthesized and characterized by powder X-ray diffraction, solid state nuclear magnetic resonance, Raman spectroscopy, and thermal analysis. The characterized multicomponent compounds include anhydrous cocrystals (malonic, succinic, glutaric, and pimelic acids), a cocrystal hydrate (adipic acid), and cocrystal solvates with acetone and tetrahydrofuran (oxalic a…
Control of the production of oxygen intermediates of human polymorphonuclear leukocytes and monocytes by beta-adrenergic receptors.
1983
The control by beta-adrenergic receptors of the production of oxygen radicals by zymosan-stimulated human polymorphonuclear leukocytes (PMN) and monocytes (M phi) was studied in vitro by means of chemiluminescence. In addition we asked whether PMN and M phi exhibit differential sensitivity to beta-adrenergic stimulation. For beta-adrenergic stimulation we applied fenoterol ranging from 10(-5) to 10(-9) M x 2.7. We found a dose-dependent suppression of the production of oxygen radicals, the ID50 being approximately 10(-6) M both for PMN and M phi. By assessment of lactic dehydrogenase release a cytotoxic effect of the drug could be ruled out. When incubated together with the beta-adrenergic …
Preparation and characterization of bio-organoclays using nonionic surfactant
2015
The present study was aimed at the preparation and characterization of tailor made hybrid materials, whose peculiar hosting capability could be exploited in biotechnological applications. With this purpose, the modification of K10 montmorillonite by intercalation of Tween 20 surfactant, was accomplished. The influence of two internal parameters, namely pH and surfactant/clay ratio, on the surfactant uptake ability by clay was investigated. The adsorption mechanism was elucidated on the basis of complementary kinetic and equilibrium studies and, then, corroborated by the useful information provided by the FT-IR, TGA and XRD characterization. The gathered results allow to draw the conclusion …
Buildup of Ultrathin Multilayer Films by a Self-Assembly Process: II. Consecutive Adsorption of Anionic and Cationic Bipolar Amphiphiles and Polyelec…
1991
We have recently reported on the consecutive physisorption of anionic and cationic bipolar amphiphiles onto charged surfaces, adsorbed out of aqueous solutions [1]. Here, we extend our previous concept to multipolar compounds such as polyelectrolytes. In contrast to the bipolar amphiphile system, it is not necessary to separate single charges by a rigid unit, when the polyelectrolyte is adsorbed from sufficiently concentrated solutions. In this case the physisorbed layer does not bind with all ionic groups to the surface and exposes free ionic groups at the new film/solution interface. Therefore a polyelectrolyte layer can replace a layer of bipolar amphiphiles in the consecutive buildup of…