Interaction between Gelatin and Nano-Silver Particle: Foundation for Nano-Silver in Antibacterial Leather

In order to explain the interaction between collagen and nano-silver, gelatin solution was blended with nano-silver particles (AgNPs) with particle size 26 mm, and then the mixture was interacted under different time, pH and temperature. The changes in the process were measured by UV-Vis, fluorescence spectroscopy, dynamic light scattering and FT-IR. The results showed that the main type of reaction between gelatin and AgNPs was electrostatic interaction and the interaction was diffusive encounters. The particle size and distribution of nano-silver would not be affected by gelatin, however, there was dynamic fluorescence quenching of gelatin after nano-silver particle induced. The longer time and lower pH were beneficial for the interaction process while the interaction balanced after 60 min and pH 3.0 resulted in the most drastic interaction. Moreover, nano-silver would not impair gelatin structure during the interaction process. In short, the results in this work might be a foundation and reference for applying nano-silver in antibacterial leather producing.

Dynamic Recognition and Tracking of Barium Flow Field Based on Deglutition Video

Dynamic fluoroscopy was used to study swallowing in 84 adult patients. We proposed a method to extract the barium contrast region by improved interframe difference method, and to indirectly determine the position of epigmatous cartilage and cricopharyngeal muscle according to the location of barium meal. The method is easy to understand, and the extraction effect is good, with 85% probability of successful extraction. On the other hand, in order to evaluate the degree of deglutition difficulty, we used calculation to evaluate variables including displacement, duration, residual quantity, etc., except that there were gender differences in variables and external factors, such as illumination, most of the measurement variables had very good reliability. The experimental results showed that the moving target fluid barium was extracted by quantifying dynamic fluorescence deglutition and using gaussian based background subtraction algorithm. We conclude that this approach significantly reduces the time it takes clinicians to examine moving images. This paper describes how to study swallowing disorders by X-ray barium fluoroscopy, explains the application of interframe difference algorithm and background subtraction in deglutiography, and extracts the residual amounts in three locations: oral cavity, epiglottic cartilage and piriform fosse.

Urea-doped carbon dots as fluorescent switches for the selective detection of iodide ions and their mechanistic study

Urea-doped carbon dots (N-CDs) have been successfully fabricated for monitoring iodide ions; the reduced lifetime of N-CDs demonstrated that the excited energy dissipation led to a dynamic fluorescence quenching process.

Hijacking of the host cell Golgi by Plasmodium liver stage parasites

The intracellular lifestyle represents a challenge for the rapidly proliferating liver stage Plasmodium parasite. In order to scavenge host resources, Plasmodium has evolved the ability to target and manipulate host cell organelles. Using dynamic fluorescence-based imaging, we show a direct interplay between the pre-erythrocytic stages of Plasmodium berghei and the host cell Golgi during the entire liver stage development. Liver stage schizonts fragment the host cell Golgi into miniaturized stacks, which increases surface interactions with the parasite’s parasitophorous vacuole membrane. Interference with the host cell Golgi-linked vesicular machinery using specific dominant-negative Arf and Rab GTPases results in developmental arrest and diminished survival of liver stage parasites. Moreover, functional Rab11a is critical for the parasites ability to induce Golgi fragmentation. Altogether, we demonstrate that the structural and functional integrity of the host cell Golgi is necessary for optimal pre-erythrocytic development of P. berghei. The parasite hijacks the hepatocyte’s Golgi structure to optimize its own intracellular development.