Electrocopolymerization kinetics of a binary mixture of 3‐chloroaniline 2‐amino‐4‐phenylthiazole and characterization of the obtained block copolymer films

Electrocopolymerization of a binary mixture of 3‐chloroaniline and 2‐amino‐4‐phenylthiazole on platinum electrode in acid medium was carried out under different reaction conditions such as temperature, current density, hydrochloric acid, and monomer concentrations with duration time. The initial rate of the electrocopolymerization reaction on platinum electrode is small and the rate law is R_p = K₂ [D]^1.29[HCl]^0.97[M]^1.94. The apparent activation energy is found to be 38.87 kJ/mol. The obtained copolymer film is characterized by ¹H‐NMR, elemental analysis, GPC IR, UV‐visible, and cyclic voltammetry and compared with those of the two homopolymers. The mechanism of the electrocopolymerization reaction is also discussed and the monomer reactivity ratio (r₁and r₂) is calculated. The thermogravimetric analysis (TGA) is used to confirm the proposed structure and determination of the number of water molecules in the polymeric chain unit. X‐ray and scanning electron microscopic analysis are used to investigate the surface morphology. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2076–2087, 2005     

In vitro and in vivo Staining Characteristics of Small,Fluorescent, Aβ42‐Binding D‐Enantiomeric Peptides in Transgenic AD Mouse Models

Plaque visualisation : We identified three different D ‐enantiomeric peptides that bind to Alzheimer's amyloid β (Aβ1‐42). As there is currently no definitive pre‐mortem diagnosis for Alzheimer's disease, we investigated the peptides' suitability as molecular probes for in vivo imaging in transgenic mouse models.

     

Inhibition of cytotoxicity and amyloid fibril formation by a D-amino acid peptide that specifically binds to Alzheimer's disease amyloid peptide

Alzheimer's disease (AD) is a progressive neurodegenerative disorder. The 'amyloid cascade hypothesis' assigns the amyloid-beta-peptide (Abeta) a central role in the pathogenesis of AD. Although it is not yet established, whether the resulting Abeta aggregates are the causative agent or just a result of the disease progression, polymerization of Abeta has been identified as a major feature during AD pathogenesis. Inhibition of the Abeta polymer formation, thus, has emerged as a potential therapeutic approach. In this context, we identified peptides consisting of d-enantiomeric amino acid peptides (d-peptides) that bind to Abeta. D-peptides are known to be more protease resistant and less immunogenic than the respective L-enantiomers. Previously, we have shown that a 12mer D-peptide specifically binds to Abeta amyloid plaques in brain tissue sections from former AD patients. In vitro obtained binding affinities to synthetic Abeta revealed a K(d) value in the submicromolar range. The aim of the present study was to investigate the influence of this d-peptide to Abeta polymerization and toxicity. Using cell toxicity assays, thioflavin fluorescence, fluorescence correlation spectroscopy and electron microscopy, we found a significant effect of the d-peptide on both. Presence of D-peptides (dpep) reduces the average size of Abeta aggregates, but increases their number. In addition, Abeta cytotoxicity on PC12 cells is reduced in the presence of dpep.     

The DESDEMONA Motion Facility: Applications for Space Research

The research facility DESDEMONA features a unique motion platform, combining a fully gimbaled cabin with the capability of producing sustained g-loads. Originally designed for ground-based simulation as well as training of spatial disorientation in aviation, the motion capabilities are also interesting for other areas. In this paper we will provide examples of space-related research questions that can be addressed on DESDEMONA. Some questions are concerned with centrifugation as a means to create artificial gravity. For instance, with its variable radius and gimbaled cabin, DESDEMONA allows for studying possible trade-offs between g-load and angular velocity. Other questions relate to the effects of g-level transitions on the astronauts’ well-being and performance. During the last two decades, research at TNO has shown that after prolonged exposure to centrifugation at 3 g astronauts experience the same vestibular adaptation symptoms as observed in real space flight. In DESDEMONA, the hyper-gravity stimulus can be applied and the consequences for control of simulated spacecraft can be examined in the same device. Furthermore, DESDEMONA also provides a ‘clinical’ tool for vestibular examination of astronauts, and for the provocation and desensitization of motion sickness in unusual G-environments.     

ANTIBACTERIAL EFFECT, HISTOLOGICAL IMPACT AND OXIDATIVE STRESS STUDIES FROM LAURUS NOBILIS EXTRACT

Laurus nobilis is one of the most broadly used spices in Moroccan gastronomy. Its antimicrobial activity against both gram-positive and gram-negative bacterial species was demonstrated. Likewise, its toxicity was investigated on Swiss albinos' mice . Daily, mice were treated orally with 0.003 and 0.3 mg during 7 days. Plasmatic markers and enzymatic systems were assessed and histological alterations were evaluated. A significant increase in creatine phosphokinase level was observed. The microscopic evaluation showed that L. nobilis induces morphological perturbation in mice's liver. The results also showed an inhibitory effect of glyceraldehydes 3-phosphate dehydrogenase and an important increase in the level of thiobarbituric acid reactive substances and succinate dehydrogenase and no change in catalase activities. The results showed that L. nobilis induces toxicity at 0.3 mg/g mouse and affects energy metabolism and oxidative stress.

PRACTICAL APPLICATIONS

The aim of the present study is to determine the antimicrobial effect of Laurus nobilis on pathogens for potential application as herbal medicine in infusion or oral preparation. The effect of the spice extract was investigated on the metabolic markers, stress biomarkers and clinical parameters. This study was completed with histological coupes. To our knowledge, this is the first report to demonstrate the laurel effect on energy metabolism and oxidative stress.     

Vehicle detection with a mobile camera: spotting midrange, distant, and passing cars

In this article, a method is presented for detecting vehicles in image sequences without prior knowledge about the position of the road. A single camera placed in a moving vehicle provides image data. For the detection of midrange and distant vehicles, a combination of three clues is used: shadow, entropy, and horizontal symmetry. To detect passing vehicles, a temporal differencing and projected motion is used. The algorithms are tested by means of many different experiments. These experiments illustrate the robust and accurate performance of both approaches.     

Refusal to eat in the elderly

Refusal to eat by the elderly, and subsequent malnutrition, occurs in both institutional and community settings. Causes include physiologic changes associated with aging, mental disorders such as dementia and depression, and medical, social, and environmental factors. Treatment approaches call for management of these causes while considering the roles that medicine, ethics, and culture play in the process.     

A complication of T-fasteners in percutaneous endoscopic gastrostomy (PEG) placement

Two patients with sinus tracts from retained T-fasteners following PEG tube placement are reported. Both patients had the PEG tubes subsequently removed and presented with purulent discharge and granulations near well-healed gastrostomy sites. The management of this complication and a possible method of prevention are discussed.     

Tendon interposition in a juxta-epiphyseal fracture of the proximal phalanx

PURPOSE: To report the clinicopathologic features of intraocular osseous production in association with proliferative vitreoretinopathy. METHOD: The clinical and histopathologic features of two patients with proliferative vitreoretinopathy and intraocular bone formation are reviewed. RESULTS: Preretinal osseous tissue incorporated in the proliferative vitreoretinopathy was surgically removed in one patient, and osseous tissue was present in the proliferative vitreoretinopathy in the enucleated eye of the other patient. CONCLUSIONS: Bone formation, presumably from metaplastic retinal pigment epithelium, may be present in proliferative vitreoretinopathy tissue. The intraocular bone is present internal rather than external to the neurosensory retina.