A Rare Manifestation of Cervical Yolk Sac Tumor in an Unfortunate Infant

Paediatric germ cell tumor is composed of various neoplasms which exhibit capricious clinical presentation and histological features depending on the age and the area of presentation. Yolk sac tumor is an extremely rare malignant tumor of embryonic origin which usually arises from the gonads. Its manifestation in the head and neck region is extremely rare. Here, we report a rare case of the malignant transformation of mature teratoma into yolk sac tumor of the neck in an infant. Diagnosis was confirmed following histopathological examination of the neck mass along with marked increase of the serum alpha-fetoprotein. The child unfortunately succumbed prior to chemotherapy. We highlight the challenge we faced in diagnosing and managing this rare entity. We would also like to recommend serial monitoring of serum alpha-fetoprotein in all patients with mature teratoma to detect malignant transformation early

Human amniotic membrane as a matrix for endothelial differentiation of VEGF-treated dental stem cells

Introduction—Endothelial cells cover the surface of the capillary wall and literature review has cemented its angiogenic roles in wound healing and tissue regeneration. However, the angiogenic in vitro models available are inadequate to understand the endothelial differentiation process. Methods—A construct was made using human amniotic membrane (HAM) as a matrix to assist the dental stem cells to differentiate into endothelial-like cells. This study aimed to assess the biological interaction between stem cells from human exfoliated deciduous teeth (SHED) and the stromal side (SS) of the glycerol-preserved HAM in angiogenic induced environment media using VEGF. The changes were evaluated through cell morphology, migration, as well as gene expression level. Results—There were morphological changes observed in SHED in angiogenic-induced media. SHED appeared to be differentiated from fibroblast-like cells to a new structure, mimicking endothelial-like structure through microscopy analysis. Besides, the cross-section of the construct revealed that the cells seeded on the matrix were able to maintain its monolayer structure at day 1, 7 and 14 but infiltrated into the HAM at day 21, suggesting cell migration. The cells were also able to maintain its stemness (Nestin, Nanog and CD29) and at the same time express the angiogenic markers (IL-8, VEGF and MMP-2). Conclusion—HAM promotes SHED proliferation, migration and has the potential as a differentiating matrix for endothelial-like cells

Swelling on the inner aspect of the lower lip

A 14-year-old man presented with 1-month history of swelling on the inner aspect of his lower lip. The swelling was painless; however, it disturbed his speech. There was no contact bleeding but had a positive history of habitual lip biting. Examination showed a single 0.5 × 1 cm2 soft oval-shaped swelling with well-circumscribed margin (Figures 1 and 2). On palpation, the mass was non-tender and had a cystic or fluctuant sensation

Evaluation of decellularization process for developing osteogenic bovine cancellous bone scaffolds in-vitro.

Current immunological issues in bone grafting regarding the transfer of xenogeneic donor bone cells into the recipient are challenging the industry to produce safer acellular natural matrices for bone regeneration. The aim of this study was to investigate the efficacy of a novel decellularization technique for producing bovine cancellous bone scaffold and compare its physicochemical, mechanical, and biological characteristics with demineralized cancellous bone scaffold in an in-vitro study. Cancellous bone blocks were harvested from a bovine femoral head (18-24 months old) subjected to physical cleansing and chemical defatting, and further processed in two ways. Group I was subjected to demineralization, while Group II underwent decellularization through physical, chemical, and enzymatic treatments. Both were then freeze-dried, and gamma radiated, finally producing a demineralized bovine cancellous bone (DMB) scaffold and decellularized bovine cancellous bone (DCC) scaffold. Both DMB and DCC scaffolds were subjected to histological evaluation, scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), fourier-transform infrared spectroscopy (FTIR), quantification of lipid, collagen, and residual nucleic acid content, and mechanical testing. The osteogenic potential was investigated through the recellularization of scaffolds with human osteoblast cell seeding and examined for cell attachment, proliferation, and mineralization by Alizarin staining and gene expression. DCC produced a complete acellular extracellular matrix (ECM) with the absence of nucleic acid content, wider pores with extensive interconnectivity and partially retaining collagen fibrils. DCC demonstrated a higher cell proliferation rate, upregulation of osteogenic differentiation markers, and substantial mineralized nodules production. Our findings suggest that the decellularization technique produced an acellular DCC scaffold with minimal damage to ECM and possesses osteogenic potential through the mechanisms of osteoconduction, osteoinduction, and osteogenesis in-vitro

Stem cells-endothelial differentiation in 3D in vitro model

lntroduction: Multipotent stem cells are characterized by its self renewal ability and potential to differentiate into many types of cell lineages. This study is focusing on angiogenesis, where the differentiation target is to turn the dental stem cells into endothelial-like cells. Thus, a 3D human amniotic membrane (HAM)-based in vitro model mimicking angiogeneic microenvironment is proposed to further understand the endothelial differentiation process. The 3D human amniotic membrane (HAM)-based scaffold is made up of stem cells from human exfoliated deciduous teeth (SHED) cultured on HAM with the addition of vascular endothelial growth factor (VEGF). Objectives: To determine the capability of SHED to undergo endothelial-like differentiation on a 3D HAM-based model. Methodology: SHED was cultured in a complete medium of alpha-minimum essential medium (a-MEM). De-epithelialised glycerol-preserved HAM was used as a scaffold while VEGF was added to induce angiogenesis. Cells were cultured in 3 groups, namely, SHED treated with VEGF (SV), SHED cultured on HAM (SA) and SHED cultured on HAM treated with VEGF (SAV). The endothelial differentiation was evaluated by scanning electron microscope (SEM), haematoxylin and eosin (H&E) and one-step RT-PCR Results: The result of SEM showed that SHED had successfully differentiated into endothelial-like cells. Through H&E staining, SHED was found forming a monolayer structure on the stromal side of HAM from day 1 until 14 but infiltrated into the structure at day 21. Meanwhile, gene expression analysis revealed that treated SHED was able to retain its stemness along with the expression of endothelial markers. Conclusion: Our 3D HAM-based in vitro model with the addition of VEGF was able to promote SHED-endothelial differentiation

Angiogenic potential of extracellular matrix of human amniotic membrane

Combination between tissue engineering and other fields has brought an innovation in the area of regenerative medicine which ultimate aims are to repair, improve, and produce a good tissue construct. The availability of many types of scaffold, both synthetically and naturally have developed into many outstanding end products that have achieved the general objective in tissue engineering. Interestingly, most of this scaffold emulates extracellular matrix (ECM) characteristics. Therefore, ECM component sparks an interest to be explored and manipulated. The ECM featured in human amniotic membrane (HAM) provides a suitable niche for the cells to adhere, grow, proliferate, migrate and differentiate, and could possibly contribute to the production of angiogenic micro-environment indirectly. Previously, HAM scaffold has been widely used to accelerate wound healing, treat bone related and ocular diseases, and involved in cardiovascular repair. Also, it has been used in the angiogenicity study, but with a different technical approach. In addition, both side of HAM could be used in cellularised and decellularised conditions depending on the objectives of a particular research. Therefore, it is of paramount importance to investigate the behavior of ECM components especially on the stromal side of HAM and further explore the angiogenic potential exhibited by this scaffold