23 research outputs found
Measurement of cardiac output by transesophageal echocardiography in mechanically ventilated patients
A Use of Modified Cyclodextrins as a Transporter for a Radiolabeled Tracer NMR Investigation
An air-stable lithiated cathode material based on a 1,4-benzenedisulfonate backbone for organic Li-ion batteries
International audienceTo meet current market demands as well as emerging environmental concerns there is a need to develop less polluting battery technologies
Solid state interaction of steroids with calixarenes. I. A preliminary FTIR and DSC study on 4-en-3-keto-steroids
Water Uptake Performance of Hygroscopic Heat and Moisture Exchangers after 24-Hour Tracheostoma Application
After total laryngectomy, patients suffer from pulmonary complaints due to the shortcut of the upper airways that results in decreased warming and humidification of inspired air. Laryngectomized patients are advised to use a heat and moisture exchanger (HME) to optimize the inspired air. According to manufacturers' guidelines, these medical devices should be replaced every 24 hours. The aim of this study is to determine whether HMEs still function after 24-hour tracheostoma application. Assessment of residual water uptake capacity of used HMEs by measuring the difference between wet and dry core weight. Tertiary comprehensive cancer center. Three hygroscopic HME types were tested after use by laryngectomized patients in long-term follow-up. Water uptake of 41 used devices (including 10 prematurely replaced devices) was compared with that of control (unused) devices of the same type and with a control device with a relatively low performance. After 24 hours, the mean water uptake of the 3 device types had decreased compared with that of the control devices. For only one type was this difference significant. None of the used HMEs had a water uptake lower than that of the low-performing control device. The water uptake capacity of hygroscopic HEMs is clinically acceptable although no longer optimal after 24-hour tracheostoma application. From a functional point of view, the guideline for daily device replacement is therefore justifie
The respective benefits of NMR and mass spectrometry in the investigation of inclusion complexes of cyclodextrins. Application to the inclusion of ionic surfactants in β- and γ-cyclodextrins
Polymeric IgA1 controls erythroblast proliferation and accelerates erythropoiesis recovery in anemia.
International audienc
Interaction of Valdecoxib with Beta Cyclodextrin: Experimental and Molecular Modeling Studies
This study aimed to investigate the effect of β-cyclodextrin on aqueous solubility and dissolution rate of valdecoxib and also to get an insight of molecular interactions involved in formation of valdecoxib‐β-cyclodextrin inclusion complex. Phase solubility analysis indicated complex with possible stoichiometry of 1:1 and a stability constant of 234.01 M−1. Thermodynamic studies in water indicated exothermic nature of inclusion complexation.␣Valdecoxib‐β-cyclodextrin complexes (1:1 M) were prepared by kneading method, solution method and␣freeze–drying method. The complex was characterized by differential scanning calorimetry (DSC), powder X-ray diffractometry (P-XRD), Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance␣(1H-NMR) spectroscopy. Molecular modeling was used to help establish the mode of interaction of β-cyclodextrin with valdecoxib. 1H-NMR analysis suggested that the unsubstituted phenyl ring of valdecoxib display favorable interaction with the hydrophobic cavity of β-cyclodextrin, which was confirmed by molecular dynamic simulations. An inclusion complex model has been established for explaining the observed enhancement of solubility of valdecoxib in water by β-cyclodextrin. Dissolution studies in water showed that the valdecoxib in freeze-dried complex dissolved much faster than the uncomplexed drug and physical mixture. This improvement in dissolution rate is attributed to the increased solubility and wettability due to encapsulation along with decreased crystallanity caused by complex formation, which is evident by DSC and P-XRD studies