Erratum : An Overview of Injectable Polymeric Hydrogels for Tissue Engineering

Bone gelatin is an important and irreplaceable item widely used in the food industry and pharmaceutical production; it is also widely used in tissue engineering and other spheres. Due to widespread use of gelatin it is necessary to search for new safe and effective technologies for bone gelatin production. This research represents the results of enzymatic-acid hydrolysis of raw material in the process of gelatin production. The article presents the results of hydrolysis analyzes, the results of the main quality parameters of the obtained gelatin samples; and the major technological scheme for gelatin production is proposed here. As result of developed technology of enzymatic-acid hydrolysis of bone raw material with the ratio of raw material mass to the volume of solvent (HCl 1M and pepsin with an enzymatic activity of 40 units) as 1:9, duration of exposure: 180 minutes (3 hours), at the stage of demineralization, liming and de-ashing, we obtained samples of gelatin at yield rate of 12.1% from the initial mass of raw materials, which is 6.9% higher in comparison with the lowest yield of gelatin according to the proposed schemes. It is shown that the samples have a high protein mass fraction 91.4%, and a low fat mass fraction 0.4%, the obtained results indicate the high technological qualities of the obtained gelatin sample, this is also confirmed by high strength of gel according to Bloom scale, which value varies within the range of 290 ± 0.7 units.

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Technology of enzymatic-acid hydrolysis of bone raw material in production of gelatine

Bioactive peptides derived from food proteins are becoming increasingly popular ingredients due to their beneficial effect on the immune system and other functional properties. We aimed to develop a technology for obtaining peptides from poultry by-products and identify their bioactivity. 
Pepsin was the main reagent for the in vitro enzymatic hydrolysis. Specialized equipment and methods were used to determine the key indicators. The molecular weight and bioactivity of the resulting peptides were calculated by using the Peptide Mass Calculator and PeptideRanker online resources. 
First, we developed a flow chart for obtaining bioactive peptides and produced hydrolysates from poultry by-products. The hydrolysates had identical physicochemical parameters, with no significant differences. The molecular weight distribution revealed that most protein fractions were represented by peptides with a molecular weight below 20 kDa. Then, we evaluated the bioactivity of the peptides. The hydrolysate obtained using pepsin with an activity of 30 units per 100 g of material showed higher bioactivity in the FD peptides (0.922094). The hydrolysate obtained using pepsin with an activity of 45 units per 100 g of material had greater bioactive properties in the CYG p eptides (0.947378). 
Based on the results, we designed a flow chart for obtaining hydrolysates from poultry by-products and evaluated the bioactive properties of the peptides obtained. For further work, these properties should be confirmed by in vitro experiments to determine the reliability of our data and identify specific bioactive properties of the peptides.

https://doi.org/10.21603/2074-9414-2022-3-2387

Identifying Bioactive Peptides from Poultry By-Products

Neurosurgical Applications of Magnetic Hyperthermia Therapy.

Injuries, surgical interventions in tumor and inflammatory processes require doctors to search for new approaches to the replacement of bone defects and optimization of osteogenesis processes. The aim of the work is to study experimentally the early general and local reactions to the implantation of a new osteoplastic material, including various combinations of calcium phosphate and silicate, during the replacement of a metaepiphyseal bone defect. For this purpose, materials of three different compositions (with the proportion of calcium phosphate to calcium silicate 60/40, 50/50 and 40/60 wt.%, respectively) were implanted in 36 rabbits in the zone of the distal metaepiphysis of the femur. The observation period was 30 days. The data of clinical examination and laboratory studies in the postoperative period and during the entire follow-up period indicated the absence of a pronounced inflammatory reaction to the implanted material. The study performed on the 30th day of CT indicates the formation of newly formed bone tissue similar to the maternal bone in density (average value 300.5 Hu). According to the results of histological examination, it was found that the implantation material with a ratio of phosphates and calcium silicates 60/40 has the best osteoregenerative characteristics in comparison with other materials presented.

The first results of experimental application of a synthetic material based on a mixture of calcium phosphate and silicate in order to stimulate the processes of reparative osteogenesis

Introduction. Meat processing enterprises are facing the problem of utilization of secondary products with a limited scope of application and a wide range of useful properties. One of the promising ways of slaughter-house by-product utilization is the production of biomaterials that can replace various tissues of a living organism. This review presents an analysis of the global biomaterials market, its volume, and possible ways of using secondary meat resources in various sectors of economy. 
Study objects and methods. The article represents some results of a desk research based on open sources, i.e. publications and Internet data portals. 
Results and discussion. One of the most important tasks of modern regenerative medicine is to develop fast and effective methods for the restoration of damaged or lost organs and tissue fragments. Its solution directly depends on new advanced biomaterials. Modern biocompatible materials are in great demand in such areas of medicine as orthopedics, ophthalmology, dentistry, general and cardiovascular surgery, restorative medicine, drug delivery, etc. Cosmetology is a rapidly evolving segment of medicine and depends on such biomaterials as hyaluronic acid and collagen. Russian biomedicine occupies 0.7% of the world market. However, the Russian segment is likely to grow and expand its range of biomaterials. 
Conclusion. The currently unused resources of meat industry can be an excellent source of valuable raw materials for the advanced biomedical structures used in tissue engineering. A wide variety of structures and properties of secondary resources can produce a wide range of biomaterials. The possibility of manufacturing matrices from internally sourced raw materials within one enterprise is particularly promising.

Global Biomaterials Market: Potential Opportunities for Raw Materials of Animal Origin

Hyperthermia (HT) has been shown to improve clinical response to radiation therapy (RT) for cancer. Synergism is dramatically enhanced if HT and RT are combined simultaneously, but appropriate tech...

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Feasibility of removable balloon implant for simultaneous magnetic nanoparticle heating and HDR brachytherapy of brain tumor resection cavities

Preliminary tests of local hyperthermia based on inductively heated tumor bed implant

Hyperthermia therapy (HT) is becoming a well-recognized method for the treatment of cancer when combined with radiation or chemotherapy. There are many ways to heat a tumor and the optimum approach depends on the treatment site. This study investigates a composite ferromagnetic surgical implant inserted in a tumor bed for the delivery of local HT. Heating of the implant is achieved by inductively coupling energy from an external magnetic field of sub-megahertz frequency. Implants are formed by mechanically filling a resected tumor bed with self-polymerizing plastic mass mixed with small ferromagnetic thermoseeds. Model implants were manufactured and then heated in a 35 cm-diameter induction coil of our own design. Experimental results showed that implants were easily heated to temperatures that allow either traditional HT (39 °C–45 °C) or thermal ablation therapy (>50 °C) in an external magnetic field with a frequency of 90 kHz and amplitude not exceeding 4 kA/m. These results agreed well with a numerical solution of combined electromagnetic and heat transfer equations solved using the finite-element method.

Alexey M. Osintsev

Papers

Global Biomaterials Market: Potential Opportunities for Raw Materials of Animal Origin

Feasibility of removable balloon implant for simultaneous magnetic nanoparticle heating and HDR brachytherapy of brain tumor resection cavities

Preliminary tests of local hyperthermia based on inductively heated tumor bed implant

Characterization of Ferromagnetic Composite Implants for Tumor Bed Hyperthermia