Dispersed copper (I) oxide particles encapsulated by polylactide

One of the approaches for the production of polymer composite materials with a biocidal effect is based on the use of dispersed particles of some metal oxides as a filler (for example, copper oxide or zinc oxide). Such an approach allows not only providing a biocidal effect, but also increasing such mechanical characteristics as the modulus of elasticity, hardness, and abrasion resistance. The mechanical characteristics of such polymer composite materials can be controlled by formation of a sheath (for example, from polylactide) of a given thickness on the surfaces of dispersed particles. Polylactide is a biodegradable polymer, widely used as coating material for particles with biocidal properties. The parameters of the methods for forming a polylactide sheath are determined by the sheath’s thickness and the sheath’s adhesion to the particle surface. The purpose of the study was to determine the parameters of the polymer sheath’s formation on the surfaces of dispersed submicron copper oxide (I) particles during coacervation of polylactide from the solution. The encapsulation of copper (I) oxide particles was carried out by the coacervation process in a solution. Polylactide was displaced from the solution in benzene by hexane in the presence of copper (I) oxide particles. It was shown that a sheath thickness of about 250 nm can be obtained by using the polylactide sheath formation method. The recommended parameters of the polylactide sheath formation method were determined: solution temperature of 35÷38 °C, hexane volume not more than 30±2 ml. The sheath had weak adhesion to particle surfaces: adhesion was determined by the roughness of the particle surface. The mechanical characteristics of the epoxy resin ED-20 polymer composition filled with the encapsulated particles were considered in the study. The increase in the mechanical properties of the polymer composition with encapsulated particles in comparison with the samples of polymer composition with non-encapsulated particles was revealed. That can indicate the increased adhesion of encapsulated particles to such polymer matrix

BAIKAL experiment: status report

We review the present status of the Baikal Neutrino Project and present the results obtained with the deep underwater neutrino telescope NT-200.Comment: 4 pages, 3 figures. Presented at TAUP 2001 (7th international workshop on Topics in Astroparticle and Underground Physics), Sep. 2001, Laboratori Nazionali del Gran Sasso, Assergi, Ital

Status of the Lake Baikal Experiment

We review the present status of the Baikal Underwater Neutrino Experiment and report on neutrino events recorded with the detector stages NT-36 and NT-96.Comment: 5 pages, 4 PostScript figures, uses here.sty and mine.sty, submitted to the Proc. of 5th Int. Workshop on Topics in Astroparticle and Underground Physics (LNGS INFN, Assergi, September 7-11, 1997

Gene-Activated Materials in Regenerative Dentistry: Narrative Review of Technology and Study Results

Treatment of a wide variety of defects in the oral and maxillofacial regions requires the use of innovative approaches to achieve best outcomes. One of the promising directions is the use of gene-activated materials (GAMs) that represent a combination of tissue engineering and gene therapy. This approach implies that biocompatible materials will be enriched with gene-carrying vectors and implanted into the defect site resulting in transfection of the recipient’s cells and secretion of encoded therapeutic protein in situ. GAMs may be presented in various designs depending on the type of material, encoded protein, vector, and way of connecting the vector and the material. Thus, it is possible to choose the most suitable GAM design for the treatment of a particular pathology. The use of plasmids for delivery of therapeutic genes is of particular interest. In the present review, we aimed to delineate the principle of work and various designs of plasmid-based GAMs and to highlight results of experimental and clinical studies devoted to the treatment of periodontitis, jaw bone defects, teeth avulsion, and other pathologies in the oral and maxillofacial regions

Refinement of Animal Experiments: Replacing Traumatic Methods of Laboratory Animal Marking with Non-Invasive Alternatives

Reliable methods for identifying rodents play an important role in ensuring the success of preclinical studies. However, animal identification remains a trivial laboratory routine that is not often discussed, despite the fact that more than 6 million rodents are used in animal studies each year. Currently, there are extensive regulations in place to ensure adequate anesthesia and to reduce animal suffering during experiments. At the same time, not enough attention is paid to the comfort of rodents during routine identification procedures, which can be painful and cause some complications. In order to achieve the highest ethical standards in laboratory research, we must minimize animal discomfort during the identification phase. In this article, we discuss traumatic methods of identification and describe several painless methods for marking in long-term experimental studies. The use of non-traumatic and non-invasive methods requires the renewal of marks as they fade and additional handling of the rodents. Laboratory personnel must be trained in stress-minimizing handling techniques to make mark renewal less stressful