Protecting the skin-implant interface with transcutaneous silver-coated skin-and-bone-integrated pylon in pig and rabbit dorsum models.

Implant-associated soft tissue infections at the skin-implant interface represent the most frequent complications in reconstructive surgery and lead to implant failures and revisions. Titanium implants with deep porosity, called skin-and-bone-integrated-pylons (SBIP), allow for skin ingrowth in the morphologically natural direction, thus restoring a reliable dermal barrier and reducing the risk of infection. Silver coating of the SBIP implant surface using physical vapor deposition technique offers the possibility of preventing biofilm formation and exerting a direct antimicrobial effect during the wound healing phase.

Hsp70-Activated NK Cells in Combination With PD-1 Inhibition Significantly Increase Overall Survival in Preclinical Models of Glioblastoma and Lung Cancer.

Heat shock protein 70 (Hsp70) which is expressed on the plasma membrane of highly aggressive tumors including non-small cell lung carcinoma and glioblastoma multiforme serves as a target for Hsp70-targeting NK cells. Herein, we aimed to investigate the antitumor effects of a combined therapy consisting of Hsp70-peptide TKD/IL-2-activated NK cells in combination with mouse/human anti-PD-1 antibody in a syngeneic glioblastoma and a xenograft lung cancer mouse model. Mice with membrane Hsp70 positive syngeneic GL261 glioblastoma or human xenograft A549 lung tumors were sham-treated with PBS or injected with TKD/IL-2-activated mouse/human NK cells and mouse/human PD-1 antibody either as a single regimen or in combination.

Granzyme B Functionalized Nanoparticles Targeting Membrane Hsp70-Positive Tumors for Multimodal Cancer Theranostics.

Functionalized superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as potential clinical tools for cancer theranostics. Membrane-bound 70 kDa heat shock protein (mHsp70) is ubiquitously expressed on the cell membrane of various tumor types but not normal cells and therefore provides a tumor-specific target. The serine protease granzyme B (GrB) that is produced as an effector molecule by activated T and NK cells has been shown to specifically target mHsp70 on tumor cells.

Evaluation of the temporary effect of physical vapor deposition silver coating on resistance to infection in transdermal skin and bone integrated pylon with deep porosity.

Periprosthetic infection via skin-implant interface is a leading cause of failures and revisions in direct skeletal attachment of limb prostheses. Implants with deep porosity fabricated with skin and bone integrated pylons (SBIP) technology allow for skin ingrowth through the implant's structure creating natural barrier against infection. However, until the skin cells remodel in all pores of the implant, additional care is required to prevent from entering bacteria to the still nonoccupied pores.

Mesenchymal Stem Cell Magnetization: Magnetic Multilayer Microcapsule Uptake, Toxicity, Impact on Functional Properties, and Perspectives for Magnetic Delivery.

Mesenchymal stem cells (MSCs) are widely used in cell therapy due to their convenience, multiline differentiation potential, reproducible protocols, and biological properties. The potential of MSCs to impregnate magnetic microcapsules and their possible influence on cell function and ability to response to magnetic field have been explored. Interestingly, the cells suspended in media show much higher ability in internalization of microcapsules, then MSCs adhere into the surface.

Application of the skin and bone integrated pylon with titanium oxide nanotubes and seeded with dermal fibroblasts.

Background: Direct skeletal attachment of limb prostheses is associated with high rate of transcutaneous infection and loosening of the fixture in the medullary canal prompting for careful assessment of various means for enhancing the skin-device and bone-device interface. The skin and bone integrated pylon system constitutes a technological platform for different modifications being evaluated previously.

Objectives: The current study assessed the combination of nano-treatment skin and bone integrated pylon with its pre-seeding with dermal fibroblasts.

Neurotherapeutic activity of the recombinant heat shock protein Hsp70 in a model of focal cerebral ischemia in rats.

Recombinant 70 kDa heat shock protein (Hsp70) is an antiapoptotic protein that has a cell protective activity in stress stimuli and thus could be a useful therapeutic agent in the management of patients with acute ischemic stroke. The neuroprotective and neurotherapeutic activity of recombinant Hsp70 was explored in a model of experimental stroke in rats. Ischemia was produced by the occlusion of the middle cerebral artery for 45 minutes.

Two-stage implantation of the skin- and bone-integrated pylon seeded with autologous fibroblasts induced into osteoblast differentiation for direct skeletal attachment of limb prostheses.

Angio- and osteogenesis following the two-stage (TS) implantation of the skin- and bone-integrated pylon seeded with autologous fibroblasts was evaluated. Two consecutive animal substudies were undertaken: intramedullary subcutaneous implantation (15 rabbits) and a TS transcutaneous implantation (12 rabbits). We observed enhanced osseointegrative properties of the intramedullary porous component seeded with fibroblasts induced into osteoblast differentiation, as compared to the untreated porous titanium pylon.

New method of fixation of in-bone implanted prosthesis.

This article presents results on the effectiveness of a new version of the titanium porous composite skin and bone integrated pylon (SBIP). The SBIP is designed for direct skeletal attachment of limb prostheses and was evaluated in a preclinical study with three rabbits. In accordance with the study protocol, a new version of the pylon (SBIP-3) was implanted into the hind leg residuum of three rabbits.

[Possibility of prediction of rat wound epithelization by changes of matrix metalloproteinases levels in wound fluid].

The engraftment of a skin sheet together with transplantation of dermal equivalent was studied on rats. The skin sheet was taken as a source of epithelization material in unhealing wound. The process of wound healing was evaluated by changes of matrix metalloproteinases (MMP) activity levels in wound fluid.

[The dependence of MMP-2 and MMP-9 activity in wound fluid on the wound tissue state at initial stages of wound healing process].

One of the problems in wound treatment optimization is the necessity of an effective and objective method of laboratory wound process monitoring. In present study the current wound process was estimated by changes in MMP-2 and MMP-9 activities in the wound fluid. An original model was used in this work to study correlation of morphological structure of the wound with the activities of MMP-2 and MMP-9 in wound fluid at various types of wound process.

Porous composite prosthetic pylon for integration with skin and bone.

This article presents results of the further development and testing of the "skin and bone integrated pylon" (SBIP-1) for percutaneous (through skin) connection of the residual bone with an external limb prosthesis. We investigated a composite structure (called the SBIP-2) made of titanium particles and fine wires using mathematical modeling and mechanical testing. Results showed that the strength of the pylon was comparable with that of anatomical bone.

[Investigation of the tissue growth processes in porous implant].

Investigation of the cell (osteocytes, fibroblasts and keratinocytes) adhesion and penetration in pores of the titanium pylon in vivo on the laboratory animals (Wistar rats) has been performed. The titanium pylon has been implanted in bone of a rat's thigh residuum. Electronic scanning and morphological analysis demonstrated the certain integration of the pylon with the surrounding tissues.

Study of Growth Processes in Bone and Skin Tissues in Porous Implants Designed for Fixation of External Prosthesis after Amputation of Extremities.

Modeling in vivo (on Wistar rats) was carried out by the method of complete integration of the prosthesis of an amputated extremity with a residuum; in this procedure the prosthesis is fixed to the residuum with a metal pylon one end of which is implanted into the bone of the residuum, while the other end traverses the residuum tissues and skin 5-7 cm above the residuum surface. This procedure includes not only successful implantation in the residuum bone, but also the possibility that the pores in the metal pylon can be filled with skin cells in the area of the pylon which traverses the tissues of the residiuum. The porous titanium pylon was implanted into the bone of experimental animals with amputated extremities.

Skin and bone integrated prosthetic pylon: a pilot animal study.

Direct skeletal attachment of limb prostheses is a viable alternative to traditional techniques that are based on a socket-residuum interface. Direct skeletal attachment may be a better or even the only method for patients with a very short residuum and high soft-tissue volume. The problem of integrating the prosthetic pylon with residual skin during direct skeletal attachment of a limb prosthesis has not been solved, and the use of a completely porous prosthetic pylon has not been the subject of focused, systematic research.

[Radiopaque oil chemical arterial embolization in treatment of pancreatic cancer].

The article is dedicated to a new method of treatment of pancreatic cancer, developed by researchers of St. Petersburg Research Institute of Roentgenology and Radiotherapy. The method consists in slowing down blood flow in the tumor by means of selective embolization of its arteries using a mixture of the chemiotherapeutic agent gemcitabine (Gemzar) in the oily radio-paque medium Lipodol Ultrafluid.

[Complex evaluation of wound healing process by a deep wound rat model with implanted polychlorvinyl camera].

A simultaneous study of wound proteolytic activity and morphological picture of the first stages of wound healing on rat deep wound model has been shown. The process of wound healing can be evaluated by dynamics of matrix metalloproteinase activities in wound fluid. Changes in activities of different matrix metalloproteinases correlate with different stages of healing.

Blood flow in the pancreatic segment before and after transplantation.

Background: Blood flow in the pancreas before and after transplantation has not been studied sufficiently. Blood flow in the pancreatic transplant as a function of type vascular anastomosis used has not been explored.

Aim: The objective of our study was to study blood flow in the intact pancreas prior to harvesting and at different time periods after transplantation.

Optimal revascularization of segmental pancreatic transplant.

Vascular anastomotic thrombosis is one of the most frequent complications after segmental transplantation of the pancreas (STP). We propose a new type of vascular anastomosis to reduce the rate of vascular thrombosis following STP. For this purpose we used double arterial-double venous anastomosis (DADVA).

[Diagnostic significance of beta 2-microglobulin after allotransplantation of cultured pancreatic islet cells of human fetus].

Twenty-nine patients with type I diabetes mellitus were followed up for at least a year after intramuscular allotransplantation of cultured fetal pancreatic islet cells. The patients were divided into 2 groups with different types of proteinuria. Group 1 (prenephritic stage) consisted of 16 patients with transitory proteinuria and group 2 (nephritic stage)-of 13 with constant proteinuria.

[Allotransplantation of pancreatic islet cells and antinuclear antibodies].

Antinuclear antibodies were detected and studied by indirect immunofluorescence in the sera of patients with insulin-dependent diabetes mellitus (IDDM) subjected to allotransplantation of pancreatic islet cell culture (PICT). Continuous cell lines L-41 (derivative of J-96) and HEp-2, a sensitive substrate for the detection of antinuclear antibodies, were used after enzyme treatment. Antinuclear antibodies were detected in 19.

[Effect of pancreatic islet cell allotransplantation on humoral immunity parameters].

The authors measured IgG, IgM, IgA, and natural sheep hemagglutinin (NSH) before and after fetal pancreatic culture allotransplantation to patients with insulin-dependent diabetes mellitus (IDDM). Patients with IDDM were found to have higher NSH levels than healthy donors. Secondary transplantations caused a more pronounced increase of NSH level than the initial ones.