Treatment of unicameral calcaneus cyst by introducing demineralized allogeneic bone paste: a case report

Background. The calcaneus is an uncommon site for unicameral bone cysts. Little is known about the etiology of these lesions. Such cysts are usually symptomatic, because of the concentration of forces through the heel and require surgical treatment in most of the cases. Material and methods. The purpose of this paper is to present a case of a 25-year-old athlete who was admitted to the Department of Microsurgery and Reconstructive Surgery with pain in the region of the right calcaneus during walking, which appeared 2 months ago. The patient underwent plain chest X-ray, general blood and urine test, all of them came normal beside the X-ray of the foot which showed a 4,0x2,0x2.0 cm cystic lesion of the right calcaneus. The patient underwent surgical treatment, which consisted of extended curettage of the cyst followed by filling of the bone defect with 10 cm3 demineralized allogeneic bone paste mixed with 10 ml ofpatientblood. The demineralized allogeneic bone paste was prepared by the Human Tissue Bank. An intraoperative Xray was performed and showed that the bone defect was filled with demineralized allogeneic bone paste. There were no early or late postoperative complications encountered. The patient was discharged from the hospital the second day after the operation. Conclusions. Imaging data are required when a cystic mass is suspected. Surgical treatment in combination with using of demineralized bone paste should be considered as an effective treatment for bone cysts. Further evaluation is required

The treatment of the optic nerve atrophy using stem cells (review)

Introduction. Tissue engineering is the evolving science that combines cells, biomaterials and biochemical factors aimed at restoring, maintaining and substituting different types of tissue. An important role is played by the use of the stem cells in various fields of medicine, including ophthalmology, namely in cases of the optic nerve atrophy. The optic nerve atrophy is the main cause of decreased visual acuity and blindness. It is considered that the use of the stem cells can be an important strategy in the treatment of the optic nerve atrophy, as the stem cells restore the structure and the function of the optic nerve due to the organotypic tissue induction and vascularization. The optic nerve atrophy is caused by irreversible apoptosis of the neuronal cells. In the absence of a specific treatment of the optic nerve atrophy, the current therapies are based on the etiological cause or late complications. Considering the availability of the advanced therapies, the therapy using stem cells offers a new approach in the treatment of the optic nerve atrophy. Aim of study. The evaluation of the latest advances of using mesenchymal stem cells based on clinical trials that included patients with optic nerve atrophy. Methods and materials. This study is a literature review, based on synthesis of clinical trials published in the period between 2009-2022. This article includes publications identified through Google Search Engines, PubMed Databases, National Bibliometric Tool, etc. The information was systematized, highlighting both aspects of the use of mesenchymal stem cells in the pathologies associated with the optic nerve atrophy, as well as the results of 24 clinical trials published on clinictrials.gov. Results. Current treatment of the optic nerve atrophy is based on the etiological causes or late complications. Considering the availability of advanced therapies, stem cell therapy offers a new approach in the treatment of the atrophy of the optic nerve. Being easy to harvest and cultivate, mesenchymal stem cells are most commonly used in regenerative medicine, they can be induced to differentiate into cartilage, tendons, adipose tissue and other cell lines. Mesenchymal stem cell harvesting has no ethical issues compared to embryonic stem cell harvesting. Also, mesenchymal stem cells are considered to be immunoprivileged because the major histocompatibility factor II is not expressed on their surface, and this great advantage allows the use of mesenchymal stem cells in autologous or allogenic form. Mesenchymal stem cells produce growth factors with paracrine action that are thought to activate endogenous repair mechanisms, due to these properties mesenchymal stem cells have been used in several clinical studies in optic nerve disorders where immunomodulatory and neuroprotective properties have been demonstrated. All of the properties mentioned above stand for the clinical use of mesenchymal stem cells in case of optic nerve atrophy. Conclusion. The clinical use of the stem cells is a great possibility for the regeneration of pathologically modified tissues. This fact requires further studies to determine how to use the cell therapy in the case of optic nerve atrophy

A new approach in the treatment of retinopathies and optic nerve atrophy using mesenchymal stem cells

Background: The tissue engineering is the evolving science that combines cells, biomaterials and biochemical factors aimed at restoring, maintaining and substituting different types of tissue. An important role is played by the use of the stem cells in various fields of medicine, including ophthalmology, namely in cases of retinopathies and optic nerve atrophy. Conclusions: Current treatment of the optic nerve atrophy is based on the etiological causes or late complications. Considering the availability of advanced therapies, stem cell therapy offers a new approach in the treatment of the atrophy of the optic nerve. Being easy to harvest and cultivate, mesenchymal stem cells are most commonly used in regenerative medicine, they can be induced to differentiate into cartilage, tendons, adipose tissue and other cell lines. Mesenchymal stem cell harvesting has no ethical issues compared to embryonic stem cell harvesting. The major histocompatibility factor II is not expressed on the surface of mesenchymal stem cells, and this great advantage allows their use in autologous or allogenic form. Mesenchymal stem cells produce growth factors with paracrine action that are thought to activate endogenous repair mechanisms, due to these properties mesenchymal stem cells have been used in several clinical studies in optic nerve disorders where immunomodulatory and neuroprotective properties have been demonstrated. All of the properties mentioned above stand for the clinical use of mesenchymal stem cells in case of optic nerve atrophy

Structural and physical characteristics of the dermal decellularized structures evaluation

Introduction. Decellularized biomaterials derived from the biological tissues are ideal for tissue engineering applications because they mimic the biochemical composition of the native tissue. The physical and structural properties of the scaffold are important in the fields of tissue engineering and regenerative medicine [1-11]. Material and methods. Study material was 20 decellularized dermal grafts. 10 samples were obtained from piglets slaughtered in the slaughterhouse. Other tissues (n=10) were received from the donor from the Human Tissue and Cell Bank of the Republic of Moldova following the recommendations of the university ethics committee. Extracellular matrices were obtained by decellularization with 0.5% sodium dodecyl sulfate/0.1% EDTA solution [12, 13, 15]. The evaluation of the structural characteristics was carried out by the histological examination with hematoxylin and eosin, scanning electron microscopy (SEM) and the quantification of the amount of deoxyribonucleic acids (DNA). Assessment of the physical characteristics included analysis of extracellular matrix (ECM) volume porosity [13-16], density [17-20], and swelling rate [16, 17]. Results. By histological examination we revealed fewer cells in decellularized tissues compared to non-decellularized ones. More than 80.5% of nucleic acids were removed from porcine matrix and 82.5% of genetic material - from decellularized human dermal structures. A mean correlation and inverse dependence of -0.43 was shown between porosity and swelling rate of decellularized dermis. Conclusions. The decellularization process significantly (P<0.05) removed the cellular components while preserving the connective three-dimensional structure of the dermal matrices clearly shown by quantification of the amount of DNA and microscopic examination of the structures

The effectiveness of the tissue engineering in the obtaining of the biological materials from the extracellular matrix

Background: The present work describes the possibility of manufacturing biomaterials from the extracellular matrix for the treatment of the skin wounds. Biomedical collagen-based materials are clinically effective. Collagen is the most abundant and major component of the skin. Porcine collagen is almost similar to the human collagen, it is not immunogenic when used for the therapeutic purposes. Biomaterials can be obtained from the decellularized dermis, being a matrix rich in the collagen and glycoproteins. Material and methods: 3 parallel groups of biomaterials were established and the average value was calculated. To ensure the effectiveness of the decellularization process, the decellularized porcine dermis was compared with the intact sample using qualitative and quantitative criteria. Results: Histologically, the decellularized tissues revealed the presence of fewer cells. As a result, were removed approximately 80.5% of the genetic material from porcine dermal structures, demonstrated by the spectrophotometric quantification of deoxyribonucleic acid. In vitro graft degradation study in 0.01 M phosphate buffer pH 7.4 combined with collagenase, demonstrated a significant (p < 0.05) loss of collagen sponge mass by 100% over one hour in the group II compared to the decellularized dermis in group I which decreased in the weight by 91.3% during 35 hours. Conclusions: Acellular biomaterials are immunologically inert, have hydrophilic and biodegradable properties, thus they can play a key role in the wound care, exerting the transfer of the bioactive molecules and drugs directly into the wound