Imidazole-Based Lithium Salt LiHDI as a Solid Electrolyte Interphase-Stabilising Additive for Lithium-Conducting Electrolytes

Lithium salt LiHDI (lithium 4,5-dicyano-2-(n-heptafluoropropyl)imidazolide) is proposed as a solid electrolyte interphase-stabilising additive for lithium-ion batteries, which can be added in a smaller amount than fluoroethylene carbonate (FEC) and vinylene carbonate (VC) additives. Electrolytes containing either lithium 4,5-dicyano-2-(trifluoromethyl)imidazolide (LiTDI) or battery-standard LiPF6 were tested with various amounts of LiHDI additive. Chemical stability in the presence of water and the thermal stability of LiHDI are on par with LiTDI. LiHDI additive does not negatively affect the properties of electrolytes. Conductivity measurements of solutions, galvanostatic cycling of graphite-LiFePO4 cells at room temperature, cells' cycling at 60 °C, internal cell resistance monitoring during cycling, and XPS analysis of electrodes' surfaces after cycling have been performed. LiHDI, unlike the FEC-VC mixture, does not negatively affect the properties of the electrolyte. Cycling showed improved capacity retention with LiHDI additive with both graphite and LiFePO4 as capacity-limiting electrodes over samples without additives. At elevated temperatures, samples with LiHDI exhibited better capacity retention during cycling than those with FEC-VC. Internal cell resistance can be correlated with capacity retention. XPS results show changes in the composition of SEI depending on the composition of the electrolyte and the duration of cycling.

Sex-specific differences in telomere length of patients with primary knee osteoarthritis

Accelerated telomere shortening is associated with age-related diseases, including osteoarthritis (OA). We aimed to determine the relative telomere length (TL) in leukocytes and cartilage of patients with primary knee OA and to investigate factors that may affect TL in OA. Relative TL measurements were performed using qPCR in leukocytes of 612 individuals (310 patients with primary knee OA undergoing total knee arthroplasty (TKA) and 302 unaffected controls). We also analysed cartilage in 57 of the 310 OA patients, measuring relative TL in severely affected and less affected (control) cartilage collected from the same knee. Cartilage TLs were compared to leukocyte TLs in all 57 patients. A significant sex-by-disease-status interaction was found in regard to relative TL. Controlling for age, the average difference of leukocyte TL between female OA patients versus female controls was 0.217 units greater than that between male OA patients versus male controls (95% CI; [0.014, 0.421]). Relative TL comparison of severely and less affected cartilage samples from the same joint showed attrition of telomeres corresponding to disease severity (0.345 mean TL difference with 95% CI of [0.151, 0.539]) in the joint. We also noted that both severely and less affected cartilage had shorter telomeres than leukocytes collected from the same patient. Severe and moderate pain in OA patients was associated with shorter TL in leukocytes, but there was no association with depression or smoking in leukocytes and cartilage. Our study indicates that sex is an important factor in OA contributing to leukocyte and cartilage TL and that pain in OA shows an inverse association only with leukocyte TL.

Oxidative Stress in Long-Term Exposure to Multi-Walled Carbon Nanotubes in Male Rats

Multi-walled carbon nanotubes (MWCNTs) serve as nanoparticles due to their size, and for that reason, when in contact with the biological system, they can have toxic effects. One of the main mechanisms responsible for nanotoxicity is oxidative stress resulting from the production of intracellular reactive oxygen species (ROS). Therefore, oxidative stress biomarkers are important tools for assessing MWCNTs toxicity. The aim of this study was to evaluate the oxidative stress of multi-walled carbon nanotubes in male rats. Our animal model studies of MWCNTs (diameter ~15-30 nm, length ~15-20 μm) include measurement of oxidative stress parameters in the body fluid and tissues of animals after long-term exposure. Rattus Norvegicus/Wistar male rats were administrated a single injection to the knee joint at three concentrations: 0.03 mg/mL, 0.25 mg/mL, and 0.5 mg/mL. The rats were euthanized 12 and 18 months post-exposure by drawing blood from the heart, and their liver and kidney tissues were removed. To evaluate toxicity, the enzymatic activity of total protein (TP), reduced glutathione (GSH), glutathione S-transferase (GST), thiobarbituric acid reactive substances (TBARS), Trolox equivalent antioxidant capacity (TEAC), nitric oxide (NO), and catalase (CAT) was measured and histopathological examination was conducted. Results in rat livers showed that TEAC level was decreased in rats receiving nanotubes at higher concentrations. Results in kidneys report that the level of NO showed higher concentration after long exposure, and results in animal serums showed lower levels of GSH in rats exposed to nanotubes at higher concentrations. The 18-month exposure also resulted in a statistically significant increase in GST activity in the group of rats exposed to nanotubes at higher concentrations compared to animals receiving MWCNTs at lower concentrations and compared to the control group. Therefore, an analysis of oxidative stress parameters can be a key indicator of the toxic potential of multi-walled carbon nanotubes.

Effect of continuous passive motion on the early recovery outcomes after total knee arthroplasty

Introduction

Continuous passive motion (CPM) is a frequently used method in the early post-operative rehabilitation of patients after knee surgery. In this study, the effectiveness of the CPM method was evaluated after primary total knee arthroplasty during an early recovery period.

Methods

Eighty patients undergoing total knee arthroplasty were assigned into two groups. The experimental group received CPM and active exercises, while the control group active exercises only. All subjects were evaluated once before the surgery and at a discharge, in terms of mean active range of motion (AROM), mean Knee Society Score (KSS), and Western Ontario and MacMaster Universities Osteoarthritis Index (WOMAC).

Results

The mean AROM for the experimental group was 82.3° ± 14.3° and 76.1° ± 22.2° for the control. The mean KSS score was 136.4 ± 19.3 points for the experimental group, and 135.7 ± 15.1 for the control. There were no statistical differences between the two groups. The KSS functional score was 66.4 ± 8.1 points for the experimental group compared to 62.2 ± 7.3 points for the control, but there was a statistically significant difference between the groups at discharge from the hospital (p = 0.009). A subjective estimation of the pain level, joint stiffness and function also showed a statistically significant difference between the two groups (38.6 ± 14.3 points for the CPM group and 21.2 ± 15.7 for the control).

Conclusion

These findings show that there is no significant effect of CPM in terms of improving clinical measurements. However, there was a significant beneficial effect on the subjective assessment of pain level, joint stiffness, and functional ability.

Long noncoding RNA CCAT1 rs67085638 SNP contribution to the progression of gastric cancer in a Polish population

The role of the long noncoding RNA CCAT1 NC_000008.10:g.128220661C > T (rs67085638) in the development of colon cancer has been reported. Therefore, we assessed the prevalence of rs67085638 in patients with gastric cancer (GC). We also evaluated the effect of rs67085638 on B-cell-specific Moloney leukaemia virus insertion site 1 (BMI1) transcripts in primary GC and counterpart histopathologically confirmed disease-free margin tissue. Using high-resolution melting analysis, we evaluated rs67085638 frequency in patients with the GC genotype (n = 214) and controls (n = 502) in a Polish Caucasian population. qRT-PCR was used to determine BMI1 transcripts. We observed the trend of rs67085638 association in all patients with GC (p_trend = 0.028), a strong risk of the GC genotype in male (p_trend = 0.035) but not female (p_trend = 0.747) patients, and the association with non-cardia GC (p_trend = 0.041), tumour stages T3 (p_trend = 0.014) and T4 (p_trend = 0.032), differentiation grading G3 (p_trend = 0.009), lymph node metastasis stage N3 (p_trend = 0.0005) and metastasis stage M0 (p_trend = 0.027). We found that significantly increased BMI1 transcripts were associated with the primary GC genotype classified as grade G3 (p = 0.011) and as lymph node metastasis N3 (p = 0.010) and counterpart marginal tissues (p = 0.026, p = 0.040, respectively) from carriers of the T/T versus C/C genotypes. rs67085638 may contribute to increased BMI1 transcripts and the progression and rapid growth of GC.

From Donor to the Lab: A Fascinating Journey of Primary Cell Lines

Primary cancer cell lines are ex vivo cell cultures originating from resected tissues during biopsies and surgeries. Primary cell cultures are objects of intense research due to their high impact on molecular biology and oncology advancement. Initially, the patient-derived specimen must be subjected to dissociation and isolation. Techniques for tumour dissociation are usually reliant on the organisation of connecting tissue. The most common methods include enzymatic digestion (with collagenase, dispase, and DNase), chemical treatment (with ethylene diamine tetraacetic acid and ethylene glycol tetraacetic acid), or mechanical disaggregation to obtain a uniform cell population. Cells isolated from the tissue specimen are cultured as a monolayer or three-dimensional culture, in the form of multicellular spheroids, scaffold-based cultures (i.e., organoids), or matrix-embedded cultures. Every primary cell line must be characterised to identify its origin, purity, and significant features. The process of characterisation should include different assays utilising specific (extra- and intracellular) markers. The most frequently used approaches comprise immunohistochemistry, immunocytochemistry, western blot, flow cytometry, real-time polymerase chain reaction, karyotyping, confocal microscopy, and next-generation sequencing. The growing body of evidence indicates the validity of the usage of primary cancer cell lines in the formulation of novel anti-cancer treatments and their contribution to drug development.

On the Sensitivity of the Ni-rich Layered Cathode Materials for Li-ion Batteries to the Different Calcination Conditions

Ni-rich layered oxides, i.e., LiNi_0.6Mn_0.2Co_0.2O₂ (NMC622) and LiNiO₂ (LNO), were prepared using the two-step calcination procedure. The samples obtained at different calcination temperatures (750–950 °C for the NMC622 and 650–850 °C for the LNO cathode materials) were characterized using nitrogen physisorption, PXRD, SEM and DLS methods. The correlation of the calcination temperature, structural properties and electrochemical performance of the studied Ni-rich layered cathode materials was thoroughly investigated and discussed. It was determined that the optimal calcination temperature is dependent on the chemical composition of the cathode materials. With increasing nickel content, the optimal calcination temperature shifts towards lower temperatures. The NMC-900 calcined at 900 °C and the LNO-700 calcined at 700 °C showed the most favorable electrochemical performances. Despite their well-ordered structure, the materials calcined at higher temperatures were characterized by a stronger sintering effect, adverse particle growth, and higher Ni²⁺/Li⁺ cation mixing, thus deteriorating their electrochemical properties. The importance of a careful selection of the heat treatment (calcination) temperature for each individual cathode material was emphasized.

Utilization of Carbon Nanotubes in Manufacturing of 3D Cartilage and Bone Scaffolds

Cartilage and bone injuries are prevalent ailments, affecting the quality of life of injured patients. Current methods of treatment are often imperfect and pose the risk of complications in the long term. Therefore, tissue engineering is a rapidly developing branch of science, which aims at discovering effective ways of replacing or repairing damaged tissues with the use of scaffolds. However, both cartilage and bone owe their exceptional mechanical properties to their complex ultrastructure, which is very difficult to reproduce artificially. To address this issue, nanotechnology was employed. One of the most promising nanomaterials in this respect is carbon nanotubes, due to their exceptional physico-chemical properties, which are similar to collagens-the main component of the extracellular matrix of these tissues. This review covers the important aspects of 3D scaffold development and sums up the existing research tackling the challenges of scaffold design. Moreover, carbon nanotubes-reinforced bone and cartilage scaffolds manufactured using the 3D bioprinting technique will be discussed as a novel tool that could facilitate the achievement of more biomimetic structures.

Plant Extracts Containing Saponins Affects the Stability and Biological Activity of Hempseed Oil Emulsion System

In this study, two saponins-rich plant extracts, viz. Saponaria officinalis and Quillaja saponaria, were used as surfactants in an oil-in-water (O/W) emulsion based on hempseed oil (HSO). This study focused on a low oil phase content of 2% v/v HSO to investigate stable emulsion systems under minimum oil phase conditions. Emulsion stability was characterized by the emulsification index (EI), centrifugation tests, droplet size distribution as well as microscopic imaging. The smallest droplets recorded by dynamic light scattering (droplets size v. number), one day after the preparation of the emulsion, were around 50-120 nm depending the on use of Saponaria and Quillaja as a surfactant and corresponding to critical micelle concentration (CMC) in the range 0-2 g/L. The surface and interfacial tension of the emulsion components were studied as well. The effect of emulsions on environmental bacteria strains was also investigated. It was observed that emulsions with Saponaria officinalis extract exhibited slight toxic activity (the cell metabolic activity reduced to 80%), in contrast to Quillaja emulsion, which induced Pseudomonas fluorescens ATCC 17400 growth. The highest-stability samples were those with doubled CMC concentration. The presented results demonstrate a possible use of oil emulsions based on plant extract rich in saponins for the food industry, biomedical and cosmetics applications, and nanoemulsion preparations.

Osteoarthritis Severely Decreases the Elasticity and Hardness of Knee Joint Cartilage: A Nanoindentation Study

The nanoindentation method was applied to determine the elastic modulus and hardness of knee articular cartilage. Cartilage samples from both high weight bearing (HWB) and low weight bearing (LWB) femoral condyles were collected from patients diagnosed with osteoarthritis (OA). The mean elastic modulus of HWB cartilage was 4.46 ± 4.44 MPa in comparison to that of the LWB region (9.81 ± 8.88 MPa, p < 0.001). Similarly, the hardness was significantly lower in HWB tissue (0.317 ± 0.397 MPa) than in LWB cartilage (0.455 ± 0.434 MPa, p < 0.001). When adjusted to patients’ ages, the mean elastic modulus and hardness were both significantly lower in the age group over 70 years (p < 0.001). A statistically significant difference in mechanical parameters was also found in grade 3 and 4 OA. This study provides an insight into the nanomechanical properties of the knee articular cartilage and provides a starting point for personalized cartilage grafts that are compatible with the mechanical properties of the native tissue.

The Role of MicroRNAs in Early Chondrogenesis of Human Induced Pluripotent Stem Cells (hiPSCs)

Human induced pluripotent stem cells (hiPSCs) play an important role in research regarding regenerative medicine. Particularly, chondrocytes differentiated from hiPSCs seems to be a promising solution for patients suffering from osteoarthritis. We decided to perform chondrogenesis in a three-week monolayer culture. Based on transcriptome analysis, hiPSC-derived chondrocytes (ChiPS) demonstrate the gene expression profile of cells from early chondrogenesis. Chondrogenic progenitors obtained by our group are characterized by significantly high expression of Hox genes, strongly upregulated during limb formation and morphogenesis. There are scanty literature data concerning the role of microRNAs in early chondrogenesis, especially in chondrogenic differentiation of hiPSCs. The main aim of this study was to investigate the microRNA expression profile and to select microRNAs (miRNAs) taking part in early chondrogenesis. Our findings allowed for selection crucial miRNAs engaged in both diminishing pluripotency state and chondrogenic process (inter alia hsa-miR-525-5p, hsa-miR-520c-3p, hsa-miR-628-3p, hsa-miR-196b-star, hsa-miR-629-star, hsa-miR-517b, has-miR-187). These miRNAs regulate early chondrogenic genes such as: HOXD10, HOXA11, RARB, SEMA3C. These results were confirmed by RT-qPCR analysis. This work contributes to a better understanding of the role of miRNAs directly involved in chondrogenic differentiation of hiPSCs. These data may result in the establishment of a more efficient protocol of obtaining chondrocyte-like cells from hiPSCs.

Effect of cellular mass on chondrogenic differentiation during embryoid body formation

One approach to cell differentiation is to use the natural capacity of pluripotent stem cells to form three germ layers via embryoid bodies (EB). However, unification of this process during in vitro culture remains challenging and many microenvironmental factors including the number of cells in the culture can influence differentiation patterns. The number of cells serves a crucial role as it determines access to nutrients, the distribution of oxygen concentration and cellular interactions, all of which influence the fate of the differentiated cells. The influence of EBs derived from human pluripotent cells on the chondrogenic potential of such cells is not well understood. For this reason, the present study sought to determine the effect of varying amounts of cells on the properties of EBs derived from human embryonic stem cells (BG01V cell line). In the present study, 500–2,000 cells per well were cultivated from 5 to 15 days in suspension cell culture. Expression of pluripotency genes and germ layer markers were evaluated in order to determine the EBs with the greatest and least mesodermal properties. Genes associated with pluripotency and chondrogenesis were also evaluated to assess the influence of suspension culture duration and EB size on chondrogenic differentiation. Immunofluorescence staining for pluripotent and chondrocyte-associated proteins confirmed successful differentiation into chondrocyte-like cells. Alcian blue staining confirmed deposition of proteoglycans. These results suggested that EBs formed in 500-cell wells possess the highest mesodermal and prochondrogenic properties. Differentiation of EBs into chondrocytes on day 5 in 500-cell wells was more efficient than in that observed in larger and older EBs.

Forced differentiation in vitro leads to stress-induced activation of DNA damage response in hiPSC-derived chondrocyte-like cells

A human induced pluripotent stem cell line (GPCCi001-A) created by our group was differentiated towards chondrocyte-like cells (ChiPS) via monolayer culturing with growth factors. ChiPS are promising because they have the potential to be used in tissue engineering to regenerate articular cartilage. However, their safety must be confirmed before they can be routinely used in regenerative medicine. Using microarray analysis, we compared the ChiPS to both GPCCi001-A cells and chondrocytes. The analysis showed that, compared to both GPCCi001-A cells and chondrocytes, the expression of genes engaged in DNA damage and in the tumor protein p53 signalling pathways was significantly higher in the ChiPS. The significant amount of DNA double strand breaks and increased DNA damage response may lead to incomplete DNA repair and the accumulation of mutations and, ultimately, to genetic instability. These findings provide evidence indicating that the differentiation process in vitro places stress on human induced pluripotent stem cells (hiPSCs). The results of this study raise doubts about the use of stem cell-derived components given the negative effects of the differentiation process in vitro on hiPSCs.

Comparison of Four Protocols to Generate Chondrocyte-Like Cells from Human Induced Pluripotent Stem Cells (hiPSCs)

Stem cells (SCs) are a promising approach to regenerative medicine, with the potential to treat numerous orthopedic disorders, including osteo-degenerative diseases. The development of human-induced pluripotent stem cells (hiPSCs) has increased the potential of SCs for new treatments. However, current methods of differentiating hiPSCs into chondrocyte-like cells are suboptimal and better methods are needed. The aim of the present study was to assess four different chondrogenic differentiation protocols to identify the most efficient method of generating hiPSC-derived chondrocytes. For this study, hiPSCs were obtained from primary human dermal fibroblasts (PHDFs) and differentiated into chondrocyte-like cells using four different protocols: 1) monolayer culture with defined growth factors (GF); 2) embryoid bodies (EBs) in a chondrogenic medium with TGF-β3 cells; 3) EBs in chondrogenic medium conditioned with human chondrocytes (HC-402-05a cell line) and 4) EBs in chondrogenic medium conditioned with human chondrocytes and supplemented with TGF-β3. The cells obtained through these four protocols were evaluated and compared at the mRNA and protein levels. Although chondrogenic differentiation of hiPSCs was successfully achieved with all of these protocols, the two fastest and most cost-effective methods were the monolayer culture with GFs and the medium conditioned with human chondrocytes. Both of these methods are superior to other available techniques. The main advantage of the conditioned medium is that the technique is relatively simple and inexpensive while the directed method (i.e., monolayer culture with GFs) is faster than any protocol described to date because it is does not require additional steps such as EB formation.

Biological and Pro-Angiogenic Properties of Genetically Modified Human Primary Myoblasts Overexpressing Placental Growth Factor in In Vitro and In Vivo Studies

Cardiovascular diseases are a growing problem in developing countries; therefore, there is an ongoing intensive search for new approaches to treat these disorders. Currently, cellular therapies are focused on healing the damaged heart by implanting stem cells modified with pro-angiogenic factors. This approach ensures that the introduced cells are capable of fulfilling the complex requirements of the environment, including the replacement of the post-infarction scar with cells that are able to contract and promote the formation of new blood vessels that can supply the ischaemic region with nutrients and oxygen. This study focused on the genetic modification of human skeletal muscle cells (SkMCs). We chose myoblast cells due to their close biological resemblance to cardiomyocytes and the placental growth factor (PlGF) gene due to its pro-angiogenic potential. In our in vitro studies, we transfected SkMCs with the PlGF gene using electroporation, which has previously been proven to be efficient and generate robust overexpression of the PlGF gene and elevate PlGF protein secretion. Moreover, the functionality of the secreted pro-angiogenic proteins was confirmed using an in vitro capillary development assay. We have also examined the influence of PlGF overexpression on VEGF-A and VEGF-B, which are well-known factors described in the literature as the most potent activators of blood vessel formation. We were able to confirm the overexpression of VEGF-A in myoblasts transfected with the PlGF gene. The results obtained in this study were further verified in an animal model. These data were able to confirm the potential therapeutic effects of the applied treatments.

Modified methods for efficiently differentiating human embryonic stem cells into chondrocyte-like cells

INTRODUCTION

Human articular cartilage has a poor regenerative capacity. This often results in the serious joint disease- osteoarthritis (OA) that is characterized by cartilage degradation. An inability to self-repair provided extensive studies on AC regeneration. The cell-based cartilage tissue engineering is a promising approach for cartilage regeneration. So far, numerous cell types have been reported to show chondrogenic potential, among others human embryonic stem cells (hESCs).

MATERIALS AND METHODS

However, the currently used methods for directed differentiation of human ESCs into chondrocyte-like cells via embryoid body (EB) formation, micromass culture (MC) and pellet culture (PC) are not highly efficient and require further improvement. In the present study, these three methods for hESCs differentiation into chondrocyte-like cells in the presence of chondrogenic medium supplemented with diverse combination of growth factors (GFs) were evaluated and modified.

RESULTS

The protocols established here allow highly efficient, simple and inexpensive production of a large number of chondrocyte-like cells suitable for transplantation into the sites of cartilage injury. The most crucial issue is the selection of appropriate GFs in defined concentration. The obtained stem-derived cells reveal the presence of chondrogenic markers such as type II collagen, Sox6 and Sox9 as well as the lack or significantly lower level of pluripotency markers including Nanog and Oct3/4.

DISCUSSION

The most efficient method is the differentiation throughout embryoid bodies. In turn, chondrogenic differentiation via pellet culture is the most promising method for implementation on clinical scale. The most useful GFs are TGF-β1, -3 and BMP-2 that possess the most chondrogenic potential. These methods can also be used to obtain chondrocyte-like cells from differentiating induced pluripotent stem cells (iPSCs).

Gene expression profile in human induced pluripotent stem cells: Chondrogenic differentiation in vitro, part B

The development of human induced pluripotent stem cells (hiPSCs) is considered a turning point in tissue engineering. However, more data are required to improve understanding of key aspects of the cell differentiation process, including how specific chondrogenic processes affect the gene expression profile of chondrocyte‑like cells and the relative value of cell differentiation markers. The main aims of the present study were as follows: To determine the gene expression profile of chondrogenic‑like cells derived from hiPSCs cultured in mediums conditioned with HC‑402‑05a cells or supplemented with transforming growth factor β3 (TGF‑β3), and to assess the relative utility of the most commonly‑used chondrogenic markers as indicators of cell differentiation. These issues are relevant with regard to the use of human fibroblasts in the reprogramming process to obtain hiPSCs. Human fibroblasts are derived from mesoderm and thus share a wide range of properties with chondrocytes, which originate from the mesenchyme. The hiPSCs were obtained from human primary dermal fibroblasts during a reprogramming process. Two methods, both involving embryoid bodies (EB), were used to obtain chondrocytes from the hiPSCs: EBs formed in the presence of a chondrogenic medium with TGF‑β3 (10 ng/ml) and EBs formed in a medium conditioned with growth factors from HC‑402‑05a cells. Based on reverse transcription-quantitative polymerase chain reaction analysis, the results demonstrated that hiPSCs are capable of effective chondrogenic differentiation, with the cells obtained in the HC‑402‑05a medium presenting with morphological features and markers characteristic of mature human chondrocytes. In contrast, cells differentiated in the presence of TGF‑β3 presented with certain undesirable hypertrophic characteristics. Several genes, most notably runt‑related transcription factor 2, transforming growth factor β2 and transforming growth factor β3, were good markers of advanced and late hiPSC chondrogenic differentiation, whereas transforming growth factor β3I, II, III receptors and bone morphogenetic protein-2, bone morphogenetic protein-4 and growth differentiation factor 5 were less valuable. These findings provide valuable data on the use of stem cells in cartilage tissue regeneration.

Gene expression profile in human induced pluripotent stem cells: Chondrogenic differentiation in vitro, part A

Human induced pluripotent stem cells (hiPSCs) offer promise in regenerative medicine, however more data are required to improve understanding of key aspects of the cell differentiation process, including how specific chondrogenic processes affect the gene expression profile of chondrocyte-like cells and the relative value of cell differentiation markers. The main aims of the present study were as follows: To determine the gene expression profile of chondrogenic-like cells derived from hiPSCs cultured in mediums conditioned with HC-402-05a cells or supplemented with transforming growth factor β3 (TGF-β3), and to assess the relative utility of the most commonly used chondrogenic markers as indicators of cell differentiation. These issues are relevant with regard to the use of human fibroblasts in the reprogramming process to obtain hiPSCs. Human fibroblasts are derived from the mesoderm and thus share a wide range of properties with chondrocytes, which also originate from the mesenchyme. Thus, the exclusion of dedifferentiation instead of chondrogenic differentiation is crucial. The hiPSCs were obtained from human primary dermal fibroblasts during a reprogramming process. Two methods, both involving embryoid bodies (EB), were used to obtain chondrocytes from the hiPSCs: EBs formed in a chondrogenic medium supplemented with TGF-β3 (10 ng/ml) and EBs formed in a medium conditioned with growth factors from HC-402-05a cells. Based on immunofluorescence and reverse transcription-quantiative polymerase chain reaction analysis, the results indicated that hiPSCs have the capacity for effective chondrogenic differentiation, in particular cells differentiated in the HC-402-05a-conditioned medium, which present morphological features and markers that are characteristic of mature human chondrocytes. By contrast, cells differentiated in the presence of TGF-β3 may demonstrate hypertrophic characteristics. Several genes [paired box 9, sex determining region Y-box (SOX) 5, SOX6, SOX9 and cartilage oligomeric matrix protein] were demonstrated to be good markers of early hiPSC chondrogenic differentiation: Insulin-like growth factor 1, Tenascin-C, and β-catenin were less valuable. These observations provide valuable data on the use of hiPSCs in cartilage tissue regeneration.

Fluorine-free electrolytes for all-solid sodium-ion batteries based on percyano-substituted organic salts

A new family of fluorine-free solid-polymer electrolytes, for use in sodium-ion battery applications, is presented. Three novel sodium salts withdiffuse negative charges: sodium pentacyanopropenide (NaPCPI), sodium 2,3,4,5-tetracyanopirolate (NaTCP) and sodium 2,4,5-tricyanoimidazolate (NaTIM) were designed andtested in a poly(ethylene oxide) (PEO) matrix as polymer electrolytes for anall-solid sodium-ion battery. Due to unique, non-covalent structural configurations of anions, improved ionic conductivities were observed. As an example, "liquid-like" high conductivities (>1 mS cm-1) were obtained above 70 °C for solid-polymer electrolyte with a PEO to NaTCP molar ratio of 16:1. All presented salts showed high thermal stability and suitable windows of electrochemical stability between 3 and 5 V. These new anions open a new class of compounds with non-covalent structure for electrolytes system applications.

Ternary mixtures of ionic liquids for better salt solubility, conductivity and cation transference number improvement

We hereby present the new class of ionic liquid systems in which lithium salt is introduced into the solution as a lithium cation-glyme solvate. This modification leads to the reorganisation of solution structure, which entails release of free mobile lithium cation solvate and hence leads to the significant enhancement of ionic conductivity and lithium cation transference numbers. This new approach in composing electrolytes also enables even three-fold increase of salt concentration in ionic liquids.

Dielectric study of interaction of water with normal and osteoarthritis femoral condyle cartilage

The main goal of this paper is the in vitro study of healthy and osteoarthritis (OA) human cartilage using the dielectric spectroscopy in the alpha-dispersion region of the electric field and in the temperatures from 25 to 140°C. The activation energy of conductivity needed to break the bonds formed by water in the extracellular matrix takes the average values of 61kJ/mol and 44kJ/mol for the control and OA cartilages, respectively. At 28°C, the small difference appears in the permittivity decrement between the control and OA cartilages, while the conductivity increment is about 2 times higher for the control tissue than that for the OA tissue. At 75°C, the conductivity increment for both of these samples is 8 times higher than their respective permittivity decrement. In addition, at 140°C the values of these both parameters for the OA tissue decrease by 8 times as compared to those recorded for the control sample. The relaxation frequency of about 10kHz is similar for both of these samples. The knowledge on dielectric properties of healthy and OA cartilage may prove relevant to tissue engineering focused on the repair of cartilage lesions via the layered structure designing.

Bioimaging: An Useful Tool to Monitor Differentiation of Human Embryonic Stem Cells into Chondrocytes

To improve the recovery of damaged cartilage tissue, pluripotent stem cell-based therapies are being intensively explored. A number of techniques exist that enable monitoring of stem cell differentiation, including immunofluorescence staining. This simple and fast method enables changes to be observed during the differentiation process. Here, two protocols for the differentiation of human embryonic stem cells into chondrocytes were used (monolayer cell culture and embryoid body formation). Cells were labeled for markers expressed during the differentiation process at different time points (pluripotent: NANOG, SOX2, OCT3/4, E-cadherin; prochondrogenic: SOX6, SOX9, Collagen type II; extracellular matrix components: chondroitin sulfate, heparan sulfate; beta-catenin, CXCR4, and Brachyury). Comparison of the signal intensity of differentiated cells to control cell populations (articular cartilage chondrocytes and human embryonic stem cells) showed decreased signal intensities of pluripotent markers, E-cadherin and beta-catenin. Increased signal intensities of prochondrogenic markers and extracellular matrix components were observed. The changes during chondrogenic differentiation monitored by evaluation of pluripotent and chondrogenic markers signal intensity were described. The changes were similar to several studies over chondrogenesis. These results were confirmed by semi-quantitative analysis of IF signals. In this research we indicate a bioimaging as a useful tool to monitor and semi-quantify the IF pictures during the differentiation of hES into chondrocyte-like.

MicroRNAs: Important Epigenetic Regulators in Osteoarthritis

Multiple mechanisms are implicated in the development of primary osteoarthritis (OA), in which genetic and epigenetic factors appear to interact with environmental factors and age to initiate the disease and stimulate its progression. Changes in expression of microRNAs (miRs) contribute to development of osteoarthritis. Numerous miRs are involved in cartilage development, homeostasis and degradation through targeting genes expressed in this tissue. An important regulator of gene expression in human cartilage is miR-140, which directly targets a gene coding aggrecanase ADAMTS-5, that cleaves aggrecan in cartilage. This miR is considered a biological marker for cartilage and its level significantly decreases in OA cartilage. On the other hand, increased expression of miR-146a in early OA inhibits two other cartilage-degrading enzymes: MMP13 and ADAMTS4, and may provide a useful tool in developing treatments for OA. The COL2A1 gene, encoding collagen type II, which is the most abundant structural protein of the cartilage, is silenced by miR-34a and activated by miR-675. Every year, new targets of cartilage miRs are validated experimentally and this opens new possibilities for new therapies that control joint destruction and stimulate cartilage repair. At the same time development of next-generation sequencing technologies allows to identify new miRs involved in cartilage biology.

The role of growth factors in stem cell-directed chondrogenesis: a real hope for damaged cartilage regeneration

PURPOSE

The use of stem cells in regenerative medicine offers hope to treat numerous orthopaedic disorders, including articular cartilage defects. Although much research has been carried out on chondrogenesis, this complicated process is still not well understood and much more research is needed. The present review provides an overview of the stages of chondrogenesis and describes the effects of various growth factors, which act during the multiple steps involved in stem cell-directed differentiation towards chondrocytes.

METHODS

The current literature on stem cell-directed chondrogenesis, in particular the role of members of the transforming growth factor-β (TGF-β) superfamily-TGF-βs, bone morphogenetic proteins (BMPs) and fibroblast growth factors (FGFs)-is reviewed and discussed.

RESULTS

Numerous studies have reported the chondrogenic potential of both adult- and embryonic-like stem cells and the role of growth factors in programming differentiation of these cells towards chondrocytes. Mesenchymal stem cells (MSCs) are adult multipotent stem cells, whereas induced pluripotent stem cells (iPSC) are reprogrammed pluripotent cells. Although better understanding of the processes involved in the development of cartilage tissues is necessary, both cell types may be of value in the clinical treatment of cartilage injuries or osteoarthritic cartilage lesions.

CONCLUSIONS

MSCs and iPSCs both present unique characteristics. However, at present, it is still unclear which cell type is most suitable in the treatment of cartilage injuries.

Osteoarthritis and telomere shortening

Osteoarthritis is the most common disease of joints caused by degradation of articular cartilage and subchondral bone. It is classified as primary form with unknown cause and as secondary form with known etiology. Genetic and epigenetic factors interact with environmental factors and contribute to the development of primary osteoarthritis. Thus far, many polymorphisms associated with osteoarthritis have been identified and recent studies also indicate the involvement of epigenetic factors (e.g., telomere shortening) in the initiation of this disorder. Accelerated shortening of telomeres was detected in osteoarthritis and other age-related diseases. Studies revealed that telomere length is severely reduced in blood leukocytes and chondrocytes of patients with osteoarthritis, and this may contribute to the initiation and development of osteoarthritis, whose major cause is still unknown.

Directed differentiation of induced pluripotent stem cells into chondrogenic lineages for articular cartilage treatment

In recent years, increases in the number of articular cartilage injuries caused by environmental factors or pathological conditions have led to a notable rise in the incidence of premature osteoarthritis. Osteoarthritis, considered a disease of civilization, is the leading cause of disability. At present, standard methods for treating damaged articular cartilage, including autologous chondrocyte implantation or microfracture, are short-term solutions with important side effects. Emerging treatments include the use of induced pluripotent stem cells, a technique that could provide a new tool for treatment of joint damage. However, research in this area is still early, and no optimal protocol for transforming induced pluripotent stem cells into chondrocytes has yet been established. Developments in our understanding of cartilage developmental biology, together with the use of modern technologies in the field of tissue engineering, provide an opportunity to create a complete functional model of articular cartilage.

Bilateral radial agenesis with absent thumbs, complex heart defect, short stature, and facial dysmorphism in a patient with pure distal microduplication of 5q35.2-5q35.3

Background

A partial duplication of the distal long arm of chromosome 5 (5q35-- > qter) is known to be associated with a distinct phenotype referred to as Hunter-McAlpine syndrome. Clinical spectrum of this disorder mainly consists of mental retardation, microcephaly, short stature, skeletal anomalies, and craniofacial dysmorphism featuring flat facies, micrognathia, large, low-set dysplastic ears, hypertelorism, almond-shaped, down-slanted palpebral fissures, epicanthal folds, small nose, long philtrum, small mouth, and thin upper lip. Less frequent remarkable findings include craniosynostosis, heart defect, hypoplastic phalanges, preaxial polydactyly, hypospadias, cryptorchidism, and inguinal hernia. In most patients with a partial duplication of 5q the aberration occurred due to an inherited unbalanced translocation, therefore the phenotype was not reflective of pure trisomy 5q.

Case presentation

We report on a 9.5-year-old boy with some feature of Hunter-McAlpine syndrome including short stature, complex heart defect (dextrocardia, dextroversion, PFO), bilateral cryptorchidism, hypothyroidism, and craniofacial dysmorphism. Additionally, bilateral radial agenesis with complete absence of Ist digital rays, ulnar hypoplasia with bowing, choroidal and retinal coloboma, abnormal biliary vesicle were identified, which have never been noted in 5q trisomy patients. Karyotype analysis, sequencing and MLPA for TBX5 and SALL4 genes were unremarkable. Array comparative genomic hybridization detected a duplication on 5q35.2-5q35.3, resulting from a de novo chromosomal rearrangement. Our proband carried the smallest of all previously reported pure distal 5q trisomies encompassing terminal 5.4-5.6 Mb and presented with the most severe limb malformation attributed to the increased number of distal 5q copies.

Conclusions

We postulate that a terminal distal trisomy of 5q35.2-5q35.3, which maps 1.1 Mb telomeric to the MSX2 gene is causative for both radial agenesis and complex heart defect in our proband. A potential candidate gene causative for limb malformation in our proband could be FGFR4, which maps relatively in the closest position to the chromosomal breakage site (about 1.3 Mb) from all known 5q duplications. Since the limb malformation as well as the underlying genetic defect are distinct from other 5q trisomy patient we propose that a position effect resulting in altered long-range regulation of the FGFR4 (alternatively MSX2) may be responsible for the limb malformation in our proband.

Expanded mutational spectrum of the GLI3 gene substantiates genotype-phenotype correlations

Greig cephalopolysyndactyly syndrome (GCPS) and isolated preaxial polydactyly type IV (PPD-IV) are rare autosomal dominant disorders, both caused by mutations in the GLI3 gene. GCPS is mainly characterised by craniofacial abnormalities (macrocephaly/prominent forehead, hypertelorism) and limb malformations, such as PPD-IV, syndactyly and postaxial polydactyly type A or B (PAPA/B). Mutations in the GLI3 gene can also lead to Pallister–Hall syndrome (PHS) and isolated PAPA/B. In this study, we investigated 16 unrelated probands with the clinical diagnosis of GCPS/PPD-IV and found GLI3 mutations in 12 (75 %) of them (nine familial and three sporadic cases). We also performed a detailed clinical evaluation of all 12 GLI3-positive families, with a total of 27 patients. The hallmark triad of GCPS (preaxial polydactyly, macrocephaly/prominent forehead, hypertelorism) was present in 14 cases (52 %), whereas at least one typical dysmorphic feature was manifested in 17 patients (63 %). Upon sequencing of the GLI3 gene, we demonstrated eight novel and two previously reported heterozygous point mutations. We also performed multiplex ligation-dependent probe amplification (MLPA) to screen for intragenic copy number changes and identified heterozygous deletions in the two remaining cases (16.7 %). Our findings fully support previous genotype–phenotype correlations, showing that exonic deletions, missense mutations, as well as truncating variants localised out of the middle third of the GLI3 gene result in GCPS/PPD-IV and not PHS. Additionally, our study shows that intragenic GLI3 deletions may account for a significant proportion of GCPS/PPD-IV causative mutations. Therefore, we propose that MLPA or quantitative polymerase chain reaction (qPCR) should be implemented into routine molecular diagnostic of the GLI3 gene.

[Effectiveness of continuous passive motion after total knee replacement]

Continuous passive motion (CPM) is frequently used method in the early post-operative rehabilitation in patients after knee surgery. Aim of this study was to evaluate the effectiveness of CPM after primary total knee arthroplasty. Efficacy was assesed in terms of clinical score and functional recovery. 93 patients (101 knee joints) undergoing total knee replacement were assigned into two groups. The experimental group received continuous passive motion and active exercises. A control group received conventional physical therapy only. CPM was initiated in the first day after surgery, for 120 minutes, starting with 0-40 degrees range of motion, increased as tolerated (mean 10 degrees per day) and maintained during the hospital stay. Outcome measures were those included in Knee Society Score (KSS). Functional recovery was evaluated using WOMAC. All subjects were evaluated once before the surgery and on 10th day postoperatively. Mean clinical score (KSS) at the day 10 was 70 +/- 15 points in the experimental group and 74 +/- 12 in a control group. There were no statistical difference between the two groups for any outcome measures. CPM group mean range of motion was 83 degrees +/- 14 degrees and a group without CPM 77 degrees +/- 21 degrees. KSS functional score was 66 +/- 9 points in the experimental group compared to 62 +/- 7 points in a control group. Subjective estimation of pain level, joint stiffness and function showed no statistical difference between the two groups regarding total and subscale scores. Mean total score was 24 +/- 19 points in the CPM group and 22 +/- 17 in a group without CPM. These findings show that CPM had no significant advantage in terms of improving clinical measurements. However, there was beneficial effect on subjective assessment of pain level, joint stiffness and functional ability.

New intermediate phenotype between MED and DD caused by compound heterozygous mutations in the DTDST gene

DTDST mutations cause a spectrum of diastrophic dysplasia disorders characterized by defects of proteoglycans sulfation. Reduction of sulfate/chloride antiporter activity is manifested by lower sulfate uptake and depends on a combination of mutations in DTDST. We analyzed a family with an autosomal recessive form of bone dysplasia. Three affected brothers from this family are compound heterozygotes for C653S/A715V mutations. We classified their phenotype as a new intermediate form between diastrophic dysplasia and multiple epiphyseal dysplasia, manifested by shortening of stature, metatarsus adductus/club foot, mild brachydactyly, proximally placed thumbs and clinodactyly of the fifth fingers. Radiographs document platyspondyly most marked in the lower thoracic and upper lumbar spine, epiphyseal dysplasia affecting predominantly the femoral heads, widening of the metaphyses, narrow growth cartilage and multilayered patellae. Exaggerated lesser trochanters of femur, that is, "monkey wrench" sign, elevated greater trochanters, thin upper pubic rami, grossly normal carpal/tarsal bones and severe, early onset osteoarthritis were other notable features.

[Clinical versus radiological mid-term results of total knee arthroplasty for degenerative arthritis of the knee]

Total knee arthroplasty (TKA) is widely accepted method for treatment of severe osteoarthritis. The aim of this paper was to retrospectively review patients operated in our institution with total condylar knee arthroplasty due to osteoarthritis and assess clinical and radiological results of this procedure. All patients treated with TKA between 1998 and 2001 were reviewed, those with diagnosis of rheumatoid arthritis were excluded from the study. One hundred and one TKA in 68 patients were studied. WOMAC protocol and KSS (Knee Society Score) were used to evaluate patients clinically, and KSS alone for radiological analysis. Bone-implant interface has been studied, position of the implants and mechanical axis of the limb both pre- and postoperatively. Excellent and good results were achieved in 89% of TKA. Subjective self-assessment was usually worse than objective one. Radiolucency was found in 16 cases (more often around tibial component than the femoral one), usually without clinical symptoms of the loosening. An accurate alignment within the range of 3 to 9 degrees valgus has been found in 68% of the knees. Subjective scores were worse than objective clinical assessment. The clinical score was higher than radiological one. The tendency to varus tibial implant fixation was observed. Suboptimal implantation has not led to implant loosening in mid-term results.

[Biomaterials in articular cartilage lesions repair]

Osteoarthritic symptoms following articular cartilage injuries are the most common musculoskeletal system disease. The treatment possibilities search for methods to restore and bring back the function of injured joint surfaces. Recent trend heads for creation of biocompatible matrices (scaffolds) based on natural and synthetic polimers. This study presents currently used biomaterials in the sphere of their usefulness in articular cartilage lesions repair. Both natural and synthetic materials have been researched in experimental and clinical studies. Naturally- derived protein polymers, such as collagen, fibrin, gelatin and carbohydrate polymers containing polylactide and polyglycolic acid, hialuronan, agarose, alginate, chitosan can be distinguished. Synthetic materials are represented by carbon fibers, Dacron and Teflon matrices. Scaffolds fabrication techniques include fiber-bonding, particulate leaching, freeze- drying and particles aggregation. Due to different polymers' properties selection of a scaffold depends on an appropriate matrix parameters. The most valuable characteristics are biocompatibility, porosity, mechanical resistance and bioabsorbability. Notwithstanding, several experimental and clinical studies there still exists the need for one simple and inexpensive polymer- based method that would bring satisfactory results in the area of joint cartilage repair.

[Application of microscopic MR for evaluation of cartilage repair]

Magnetic resonance imaging is gold standard for noninvasive evaluation of articular cartilage damage and has been also used for monitoring cartilage repair. The aim of this study was to find correlation between histological microscopy and microscopic MR in evaluation of the repair of osteochondral defects in articular cartilage. Study was based animal model (rabbit). The cartilage repair process was evaluated histology and micro MR. Most of the defects were filled with fibrocartilage and fibrous tissue formed. Both methods were equally efficient to show repair tissue thickness, subchondral bone reconstruction and disintegration. Result of observation by both histological and MR microscopy and showed good correlation. Micro MR is promising evaluation tool for cartilage repair monitoring. Results of micro MR correlate well with standard microscopy.

Articular cartilage repair by means of biodegradable scaffolds

INTRODUCTION

Articular cartilage has a limited capacity for self-repair; untreated injuries of cartilage may lead to osteoarthritis. In severe cases the only choice a total joint replacement, may be inadequate in young patients. This problem demands new effective methods to reconstruct articular cartilage. The aim of this study was to evaluate the application of collagen matrix for the reconstruction of articular cartilage.

MATERIALS AND METHODS

A group of 28 rabbits had a defect penetrating into the subchondral constructed and either filled with collagen scaffold (group I) or remained empty (group II). The results were observed after 4 and 12 weeks. Macroscopic and microscopic evaluations were performed.

RESULTS

In the first group we observed the presence of hyalinelike cartilage resembling normal articular cartilage. In the second group fibrous tissue dominated. The surface of regenerated tissue was smooth, intact, and the defect completely filled with regenerated tissue, showing good structural integrity. In the second group, superficial irregularities, disorders of structural integrity, and necrotic features were noticed.

CONCLUSIONS

This study showed better results of articular cartilage reconstruction by means of a biodegradable scaffold.

Evaluation of Cartilage Reconstruction by Means of Autologous Chondrocyte Versus Periosteal Graft Transplantation: An Animal Study

BACKGROUND

Autologous chondrocyte transplantation (ACT) has been shown to heal cartilage defects under experimental and clinical conditions. However, the evaluation of successful transplantation still remains arbitrary and further research is required to establish objective criteria of treatment. The aim of the present study was to evaluate the criteria of successful ACT and to compare the results with those obtained following periosteal grafting (PG).

MATERIALS AND METHODS

Articular cartilage specimens were taken from the distal femur of 30 adolescent New Zealand rabbits and chondrocytes were obtained by collagenase digestion. The chondrocytes were identified by a functional assay, based on estimating procollagen type II mRNA by reverse-transcribed polymerase chain reaction. The cells cultured in vitro were transplanted under a periosteal flap into a full thickness defect (ICRS III(0)). The quality of the repaired tissue was evaluated macroscopically according to a modified scale of Brittberg et al, and microscopically according to O'Driscoll et al. For comparative purposes animals treated with PG were used.

RESULTS

Cultured chondrocytes expressed procollagen type II and, upon transplantation into the defect, produced hyaline cartilage. To evaluate the results of transplantation, two categories of criteria were adopted-macroscopic analysis and microscopic examination. By all adopted criteria the results were significantly better in the ACT group (P < .05) than in the PG group.

CONCLUSION

Prior to transplantation, assays for specialized functions of chondrocytes required semiquantitative evaluation of macroscopic and microscopic appearance of the repaired tissue, showing the benefit of autologous chondrocyte versus periosteal graft transplantation.

[Value of collagen scaffolds in surgical reconstruction of articular cartilage]

Articular cartilage has a very limited capacity for regeneration and the untreated injuries of this tissue may lead to osteoarthritis. The aim of this study was to evaluate the application of collagen scaffolds in surgical reconstruction of articular cartilage. A group of 28 rabbits was used in the study. A defect penetrating into the subchondral bone was made. The animals were divided into 2 groups: group 1- defects filled with collagen scaffold, group II the defects remained empty. The results were evaluated at 4 a 12 weeks. Macroscopic and microscopic evaluation was performed. On gross examination of the group I complete filling of the defect with regenerated tissue was observed. This tissue had smooth surface and was completely integrated with the surrounding cartilage. In the group II the surface of the newly formed tissue showed large irregularities. The defect was partially filled and incompletely integrated with the residual cartilage. Microscopic results indicate presence of hyaline-like cartilage resembling normal articular cartilage in group I. Regenerate was more stable and remained stable with longer follow-up. Group II revealed mostly fibrous tissue in regenerate. Thickness was inadequate with visible surface irregularities and loss in tissue integrity. This study proved better results of reconstruction of articular cartilage by means of biodegradable scaffold.

[Value of osteo-chondral paste autologous transplantation in experimental cartilage defects reconstruction. Part III--Microscopic analysis of reconstructed cartilage thickness and surface regularity]

INTRODUCTION

A limited ability of the cartilage to heal after trauma was the reason to start research on new methods concerning better cartilage reconstruction. The aim of the study was evaluation of repair tissue thickness and surface regularity after osteochondral paste transplantation.

MATERIAL AND METHODS

Full thickness defect (IV(o)--ICRS scale) on distal rabbit femur joint surface was made. Three groups were specified: A--defect with paste graft (cartilage and contiguous bone collected from joint surface, crushed into homogenous paste; B--defect with the paste graft covered with periosteum; C--defect left unfilled. The follow-up periods were established at 4, 8, 12 weeks. Repair tissue was evaluated microscopically according to modified O'Driscoll scale.

RESULTS

Newly formed tissue was well integrated with surrounding cartilage in group A (paste graft). That trait of repair tissue in group A was much better than in other groups, especially in late observations. Structural integrity of tissue filling the defect was similar to integrity of normal cartilage in groups A and C, but tissue formed in group C didn't represent a hyaline-like cartilage character. In all the examined groups reconstruction of subchondral bone exhibited similar rate. 12 weeks from the procedure, around 80% of subchondral bone was rebuilt. The obtained results indicate, that osteochondral paste autologous transplantation in cartilage defects treatment effects with forming well integrated (structurally and with surrounding cartilage) cartilage tissue, of almost complete subchondral bone rebuilding.

[Value of autologous chondrocyte transplantation in experimental cartilage defects reconstruction. Part IV--Microscopic analysis of repair tissue degenerative changes (cellularity and signs of necrosis)]

Articular cartilage cells are immersed in semi-solid matrix and isolated from the rest of the body because of lack of nervous fibres, and blood and lymphatic vessels. Trauma and aging processes result in cartilage ultrastructure disorders. Those changes leads to progressive decreasing of durability and rigidity of cartilage. Research on articular cartilage reconstruction focuses on, among other things, reaching by newly formed tissue optimal amount of vital cells. The aim of this part of the study was microscopic evaluation of repair tissue degenerative changes (cellularity and signs of necrosis).

MATERIAL AND METHODS

Repair of partial thickness cartilage defect (III tertiary grade) on distal femur joint surface was evaluated (25 adolescent rabbits). Procedures were performed in two groups: I--autologous chondrocyte transplantation under periosteal flap, II--periosteal graft. Chondrocytes were isolated from the cartilage specimens by enzymatic digestion and cultured in vitro. The follow-up periods were established at 4, 8 and 12 weeks. Repair tissue was evaluated microscopically according to modified O'Driscoll scale.

RESULTS

Repair tissue cellularity. In group I (with chondrocytes), 4 weeks after the procedure tissue of high cellularity was formed, corresponding in amount of cells to the structure of early differentiated hyaline-like cartilage. Amount of cells slightly decreased with time, as it occurs in maturing cartilage. In group II (without chondrocytes), 4 weeks after the procedure the repair tissue was characterized by small amount of cells, which was decreasing with time. Signs of necrosis. In group I, 4, 8 and 12 weeks after the procedure moderate intensity of necrotic signs was observed. In group II, significant intensity of necrosis signs in all observation periods was observed.

CONCLUSION

Obtained results indicate, that autologous chondrocyte transplantation in treatment of partial thickness cartilage defects effects with forming tissue of high cellularity, not degenerating with time, much better as compared to untreated defect.

[Value of autologous chondrocyte transplantation in experimental cartilage defects reconstruction. Part II: Microscopic analysis of reconstructed cartilage structural integrity and surface regularity]

Experimental and clinical tests proved that cultured, autologous chondrocytes retain their properties and have ability to reconstruct hyaline-like cartilage, which represents chemical composition and biomechanical characteristics similar to normal hyaline cartilage. The aim of this part of the study was microscopic evaluation of repair tissue structural integrity and surface regularity after autologous chondrocyte transplantation.

MATERIAL AND METHODS

Repair of partial thickness cartilage defect (ICRS III(o) grade) on distal femur joint surface was evaluated (25 adolescent rabbits). Procedures were performed in two groups: I--autologous chondrocyte transplantation under periosteal flap, II--periosteal graft. Chondrocytes were isolated from the cartilage specimens by enzymatic digestion and cultured in vitro. The follow-up periods were established at 4, 8, 12 weeks. Repair tissue was evaluated microscopically according to modified O'Driscoll scale.

RESULTS

In group I, 4 weeks after the procedure surface of the reconstructed tissue was irregular. 8- and 12-week observation found the surface regular and plain, and repair tissue exhibited complete structural integrity. In group II, in all follow-up periods regenerate surface was irregular, there was many fissures and cracks in graft tissue, and in several cases--regenerate disintegration.

CONCLUSION

Obtained results indicate, that hyaline-like cartilage reconstructed after autologous chondrocyte transplantation was characterized by regular, plain surface and complete structural integrity.

[Morton's Metatarsalgia--a case report]

The authors describe the case of a 51 years old woman with interdigital neuroma at a level of II and IV metatarsal heads--Morton's Metatarsalgia.

[Value of autologous chondrocyte transplantation in experimental cartilage defects reconstruction. Part III--Microscopic analysis of reconstructed cartilage thickness and integration with surrounding tissue]

Lack of cartilage vascularization is the reason of its low regenerative potential. The aim of this part of the study was microscopic evaluation of repair tissue thickness and its integration with surrounding cartilage, after autologous chondrocyte transplantation.

MATERIAL AND METHODS

Repair of partial thickness cartilage defect (ICRS III(o) grade) on distal femur joint surface was evaluated (25 adolescent rabbits). Procedures were performed in two groups: I--autologous chondrocyte transplantation under periosteal flap, II--periosteal graft. Chondrocytes were isolated from the cartilage specimens by enzymatic digestion and cultured in vitro. The follow-up periods were established at 4, 8, 12 weeks. Repair tissue was evaluated microscopically according to modified O'Driscoll scale.

RESULTS

In group I, 8 weeks after the procedure most of defects were filled with the newly formed tissue almost completely. Regenerate thickness after 4 and 12 weeks usually exceeded 1/2 of surrounding cartilage. In group II, 8 weeks after the procedure regenerate thickness amounted to at least 1/2 of surrounding cartilage, but 4- and 12-week observation revealed the decreased repair tissue thickness. In group I, 4 weeks after the procedure regenerative tissue was well integrated with surrounding cartilage, and this trait still gradually increased with time. In group II, there was partial integration or no integration of repair tissue with surrounding cartilage.

CONCLUSION

Obtained results indicate, that tissue formed after autologous chondrocyte transplantation with use of periosteal flap was better in its thickness and integration with surrounding cartilage, as compared to tissue formed after use of periosteum alone. Autologous chondrocyte transplantation can not guarantee complete filling of the cartilage defect with the graft tissue and full integration with surrounding cartilage, without three-dimensional scaffold application.

[Value of osteo-chondral paste autologous transplantation in experimental cartilage defects reconstruction. Part IV--Microscopic analysis of cellularity and of traits of necrosis in the defect-filling tissue]

INTRODUCTION

Restricted potential of cartilage to regeneration following trauma induced search for new techniques of articular cartilage repair. Present study aimed at defining in experimental conditions of autologous osteochondral paste value by evaluation of cellularity and presence of necrosis in the defect-filling tissue.

MATERIAL AND METHODS

Full thickness defect (IV(o)--ICRS scale) on distal rabbit femur joint surface was made. Three groups were specified: A--defect with paste graft (cartilage and contiguous bone collected from joint surface, crushed into homogenous paste; B--defect with the paste graft covered with periosteum; C--defect left unfilled. The follow-up periods were established at 4, 8, 12 weeks. Repair tissue was evaluated microscopically according to modified O'Driscoll scale.

RESULTS

In evaluation of cellularity in the developed repair tissue, in long-term observations best results were obtained in the group of osteochondral paste (A) and in the group of unfilled defect (C). Following 12 weeks of observation cellularity of the repair tissue in the groups amounted to around 95%, as compared to the surrounding healthy cartilage. In evaluation of necrotic traits in the newly developed tissue, their highest intensity after 4 weeks of observation was noted in the group with periosteum covered osteochondral paste (B), and lower but still significant in the group in which paste alone was applied (A). This resulted from massive dying out of the grafted bone elements, and in the case of group B, also of the periosteal cells in the covering flap and of certain number of chondrocytes composing the graft. The trait was more objectively evaluated in long-term observations, when necrotic foci involved only elements of the proper repair tissue. After 12 weeks of observation degenerative changes showed the least pronounced intensity in the group with the paste alone (A). Following 4 weeks the intensity was least pronounced in the group with the unfilled defect (C), i.a. due to the absence of graft with the decomposing bone elements. However, with elapsing time degenerative lesions intensified in the group, pointing to the low stability of the developed tissue. The results indicated that application of the osteochondral paste in treatment of cartilage defects yields a stable, highly cellular tissue, resistant to time and trauma.

[Graft remodeling following Hertel ACL reconstruction in MR imaging]

MRI and clinical assessment of 21 patients operated on with Hertel method due to knee instability has been presented. Position of the graft in reference to the Blumensaat line has been evaluated in MRI with the use of 3 point scale after mean follow-up of 9-months. Four points scale has been used to grade signal intensity as indicator of graft remodeling. Lysholm scale served for clinical assessment. Mean grade for graft position was 2.3 and for signal intensity 2.7. Better remodeling of the graft correlated positively with its better positioning, but clinical assessment correlated poorly with signal intensity and localization of the graft. Incorrect positioning of the graft hinders its remodeling--ligamentization of the tendon.

[The value of autologous osteochondral paste for in-vitro treatment of damage to articular cartilage. Part I. Macroscopic and microscopic assessment of the regenerated articular surface]

The limited ability of articular cartilage to regenerate after trauma has been the main reason for research of new repair techniques. The aim of this paper was to assess in in-vitro conditions the value of autologous osteochondral of pulp--macroscopic analysis of the regenerated articular surface and microscopic assessment of the dominant tissue in the regenerate. The experimental model consisted of a full-depth cartilage defect of the articular surface of the distal femur in rabbits. The animals were subdivided into 3 groups: group A--with defect with osteochondral of pulp, group B--with defects filled with osteochondral of pulp covered by periosteum, group C--defect untreated. After observation periods of 4, 8 and 12 weeks the regenerates were assessed using the Brittberg and O'Driscoll scale. In the overall macroscopic assessment group A prevailed because of the best defect filling. Microscopic assessment showed that in group A the defect had been filled with cartilage very similar to hyaline cartilage (hyaline--like cartilage). Basing on the result of the experiment, we assume that osteochondral of pulp has chondrogenic properties.