Guided Bone Regeneration in the Edentulous Atrophic Maxilla Using Deproteinized Bovine Bone Mineral (DBBM) Combined with Platelet-Rich Fibrin (PRF)-A Prospective Study

Background: Bone regeneration procedures represent a major challenge in oral surgery. This study aimed to evaluate a composite PRF/particulate xenograft in guided bone regeneration. Methods: Edentulous patients with horizontal ridge deficiencies in the anterior maxilla and candidates to an immediate-loading full-arch rehabilitation were included. Horizontal linear measurements indicating bone gain were assessed from computer beam computer tomography (CBCT) scans obtained at pre-surgery, post-surgery, and the 12-month follow-up. Mean bone values were presented as mean ± 95% CI. Non-parametric tests were used as appropriate, and the effect size was calculated with Cohen’s d repeated measures. Results: Eighteen patients were rehabilitated with 72 implants. The mean horizontal bone width was 4.47 [4.13–4.80] mm pre-surgically, 9.25 [8.76–9.75] mm post-surgically, and 7.71 [7.28–8.14] mm 12 months after. Conclusions: PRF associated with a xenograft seems to promote an effective horizontal bone gain. Randomized clinical trials are needed to confirm the benefits of this surgical approach.

Single-Shot Local Injection of Microfragmented Fat Tissue Loaded with Paclitaxel Induces Potent Growth Inhibition of Hepatocellular Carcinoma in Nude Mice

Hepatocellular carcinoma (HCC) is poorly beneficiated by intravenous chemotherapy due to inadequate availability of drugs at the tumor site. We previously demonstrated that human micro-fragmented adipose tissue (MFAT) and its devitalized counterpart (DMFAT) could be effective natural scaffolds to deliver Paclitaxel (PTX) to tumors in both in vitro and in vivo tests, affecting cancer growth relapse. Here we tested the efficacy of DMFAT-PTX in a well-established HCC in nude mice. MFAT-PTX and DMFAT-PTX preparations were tested for anti-cancer activity in 2D and 3D assays using Hep-3B tumor cells. The efficacy of DMFAT-PTX was evaluated after a single-shot subcutaneous injection near a Hep-3B growing tumor by assessing tumor volumes, apoptosis rate, and drug pharmacokinetics in an in vivo model. Potent antiproliferative activity was seen in both in vitro 2D and 3D tests. Mice treated with DMFAT-PTX (10 mg/kg) produced potent Hep-3B growth inhibition with 33% complete tumor regressions. All treated animals experienced tumor ulceration at the site of DMFAT-PTX injection, which healed spontaneously. Lowering the drug concentration (5 mg/kg) prevented the formation of ulcers, maintaining statistically significant efficacy. Histology revealed a higher number of apoptotic cancer cells intratumorally, suggesting prolonged presence of PTX that was confirmed by the pharmacokinetic analysis. DMFAT may be a potent and valid new tool for local chemotherapy of HCC in an advanced stage of progression, also suggesting potential effectiveness in other human primary inoperable cancers.

Use of Amniotic Membrane and Its Derived Products for Bone Regeneration: A Systematic Review

Thanks to their biological properties, amniotic membrane (AM), and its derivatives are considered as an attractive reservoir of stem cells and biological scaffolds for bone regenerative medicine. The objective of this systematic review was to assess the benefit of using AM and amniotic membrane-derived products for bone regeneration. An electronic search of the MEDLINE-Pubmed database and the Scopus database was carried out and the selection of articles was performed following PRISMA guidelines. This systematic review included 42 articles taking into consideration the studies in which AM, amniotic-derived epithelial cells (AECs), and amniotic mesenchymal stromal cells (AMSCs) show promising results for bone regeneration in animal models. Moreover, this review also presents some commercialized products derived from AM and discusses their application modalities. Finally, AM therapeutic benefit is highlighted in the reported clinical studies. This study is the first one to systematically review the therapeutic benefits of AM and amniotic membrane-derived products for bone defect healing. The AM is a promising alternative to the commercially available membranes used for guided bone regeneration. Additionally, AECs and AMSCs associated with an appropriate scaffold may also be ideal candidates for tissue engineering strategies applied to bone healing. Here, we summarized these findings and highlighted the relevance of these different products for bone regeneration.

Stable Co-Cultivation of the Moss Physcomitrella patens with Human Cells in vitro as a New Approach to Support Metabolism of Diseased Alzheimer Cells

Alzheimer's disease (AD) is a devastating slowly progressive neurodegenerative disorder with no cure. While there are many hypotheses, the exact mechanism causing this pathology is still unknown. Among many other features, AD is characterized by brain hypometabolism and decreased sugar availability, to which neurons eventually succumb. In light of this aspect of the disease, we hypothesized that boosting fuel supply to neurons may help them survive or at least alleviate some of the symptoms. Here we demonstrate that live moss Physcomitrella patens cells can be safely co-cultured with human fibroblasts in vitro and thus have a potential for providing human cells with energy and other vital biomolecules. These data may form the foundation for the development of novel approaches to metabolic bioengineering and treatment of diseased cells based on live plants. In addition, by providing alternative energy sources to human tissues, the biotechnological potential of this interkingdom setup could also serve as a springboard to foster innovative dietary processes addressing current challenges of mankind such as famine or supporting long-haul space flight.

Proposal of a Novel Natural Biomaterial, the Scleral Ossicle, for the Development of Vascularized Bone Tissue In Vitro

Recovering of significant skeletal defects could be partially abortive due to the perturbations that affect the regenerative process when defects reach a critical size, thus resulting in a non-healed bone. The current standard treatments include allografting, autografting, and other bone implant techniques. However, although they are commonly used in orthopedic surgery, these treatments have some limitations concerning their costs and their side effects such as potential infections or malunions. On this account, the need for suitable constructs to fill the gap in wide fractures is still urgent. As an innovative solution, scleral ossicles (SOs) can be put forward as natural scaffolds for bone repair. SOs are peculiar bony plates forming a ring at the scleral-corneal border of the eyeball of lower vertebrates. In the preliminary phases of the study, these ossicles were structurally and functionally characterized. The morphological characterization was performed by SEM analysis, MicroCT analysis and optical profilometry. Then, UV sterilization was carried out to obtain a clean support, without neither contaminations nor modifications of the bone architecture. Subsequently, the SO biocompatibility was tested in culture with different cell lines, focusing the attention to the differentiation capability of endothelial and osteoblastic cells on the SO surface. The results obtained by the above mentioned analysis strongly suggest that SOs can be used as bio-scaffolds for functionalization processes, useful in regenerative medicine.

Engineering natural heart valves: possibilities and challenges

Heart valve replacement is considered to be the most prevalent treatment approach for cardiac valve-related diseases. Among current solutions for heart valve replacement, e.g. mechanical and bioprosthetic valves, the main shortcoming is the lack of growth capability, repair and remodelling of the substitute valve. During the past three decades, tissue engineering-based approaches have shown tremendous potential to overcome these limitations by the development of a biodegradable scaffold, which provides biomechanical and biochemical properties of the native tissue. Among various scaffolds employed for tissue engineering, the decellularized heart valve (DHV) has attracted much attention, due to its native structure as well as comparable haemodynamic characteristics. Although the human DHV has shown optimal properties for valve replacement, the limitation of valve donors in terms of time and size is their main clinical issue. In this regard, xenogenic DHV can be a promising candidate for heart valve replacement. Xenogenic DHVs have similar composition to human valves, which will overcome the need for human DHVs. The main concern regarding xenogeneic DHV replacement is the immunological reaction and calcification following implantation, weak mechanical properties and insufficient recellularization capacity. In this review, we describe the essential steps required to address these impediments through novel engineering approaches. Copyright © 2016 John Wiley & Sons, Ltd.

Native multipotential stromal cell colonization and graft expander potential of a bovine natural bone scaffold

Graft expanders are bone scaffolds used, in combination with autografts, to fill large bone defects in trauma surgery. This study investigates the graft expander potential of a natural bone substitute Orthoss by studying its ability to support attachment, growth and osteogenic differentiation of neighboring multipotential stromal cells (MSCs). Material consisting of bone marrow (BM) aspirate and reamer-irrigator-aspirator (RIA)-harvested autograft bone was co-cultured with commercially available Orthoss granules. Native MSCs attached to Orthoss were expanded and phenotypically characterized. MSCs egress from neighboring cancelous bone was assessed in 3D Matrigel co-cultures. MSC differentiation was evaluated using scanning electron microscopy and measuring alkaline phosphatase (ALP) activity per cell. CD45(+) hematopoietic lineage cells and highly proliferative CD90(+) CD73(+) CD105(+) MSCs preferentially colonized Orthoss granules, over RIA bone chips. MSC colonization was followed by their intrinsic osteogenic differentiation, assessed as mineral deposition and gradual rise in ALP activity, even in the absence of osteogenic stimuli. When in contact with mixed cell populations and RIA chips, Orthoss granules support the attachment, growth and osteogenic differentiation of neighboring MSCs. Therefore, natural bone substitutes similar to Orthoss can be used as void fillers and graft expanders for repairing large bone defects in conjunction with autologous BM aspirates and autografts.

Successful recellularization of human tendon scaffolds using adipose-derived mesenchymal stem cells and collagen gel

The major goal of regenerative medicine is to determine experimental techniques that take maximal advantage of reparative processes that occur naturally in the animal body. Injection of mesenchymal stem cells into the core of a damaged tendon represents such an approach. Decellularization of native tendons as potential targets and seeding protocols are currently under investigation. The aim of our study was to manufacture a recellularized biocompatible scaffold from cadaveric tissue for use in total or partial tendon injuries. Results showed that it was possible to introduce proliferating cells into the core of a decellularized tendon to treat the scaffold with a collagen gel. The method was effective in maintaining scaffold extracellular matrix and for expressing collagen type I and cartilage oligomeric matrix protein by injecting mesenchymal stem cells.