Bioprinting with live cells

Tissue engineering is an emerging multidisciplinary field to regenerate damaged or diseased tissues and organs. Traditional tissue engineering strategies involve seeding cells into porous scaffolds to regenerate tissues or organs. However, there are still some challenges such as difficulty in seeding different type of cells spatially into a scaffold, limited oxygen and nutrient delivery and removal of metabolic waste from scaffold and weak cell-adhesion to scaffold material need to be overcome for clinically successful results. Because of those challenges, novel scaffold-free approaches based on cellular self-assembly or three-dimensional (3D) bioprinting have been recently pursued. Bioprinting is a relatively new technology where living cells with or without biomaterials are printed layer-by-layer in order to create 3D living structures. In 3D bioprinting, cell aggregates and hydrogels are termed as bioink used as building blocks that are placed by the bioprinter into precise architecture according to developed computer models. In this chapter, we focus on the scaffold-free, self-assembly based bioprinting approaches and some of the novel developments in this field. This chapter will also discuss the importance as well as the challenges for 3D bioprinting using stem cells. We aim to highlight the importance of the continuous cell printing in order to fabricate 3D biological structures with predefined shapes as being the building blocks of large and complex tissues

Prevalence of Metabolic Syndrome in Patients with Psoriasis

Background. Psoriasis is a chronic inflammatory skin disorder in which proinflammatory cytokines including IL-6 and TNF-α increase both locally and systematically. It is thought that chronic inflammation results in metabolic diseases and proinflammatory cytokines give rise to the development of atherogenesis, peripheral insulin resistance, hypertension, and type 2 diabetes. Our aim was to investigate the prevalence of metabolic syndrome in patients with psoriasis vulgaris. Methods. Study consisted of 115 plaque-type psoriasis patients and 140 healthy individuals. Data including body weight, height, waist circumference, body-mass index, and arterial blood pressure were collected. Fasting blood glucose, triglyceride, and HDL levels were determined. International Diabetes Federation Criteria for Metabolic Syndrome and Insulin Resistance were used for evaluating patients with metabolic syndrome and diabetes. Results. Compared to the control group, metabolic syndrome, diabetes mellitus, and hypertension were found to be higher in psoriasis patients. Metabolic syndrome was increased by 3-folds in psoriasis patients and was more prevalent in women than in men. It was determined that the prevalence of metabolic syndrome was higher in psoriasis patients after the age of 40. Metabolic syndrome was not related to smoking, severity of psoriasis, and duration of disease. Conclusions. Our findings suggest that psoriasis preconditions occurrence of a group of diseases such as diabetes mellitus, hypertension, and metabolic syndrome. For this reason, patients with psoriasis should be treated early and they should be followed with respect to metabolic diseases

3D hybrid bioprinting of macrovascular structures

Thousands of people die each year due the cardiovascular health problems. The most common treatments for cardiovascular health diseases are autografts and blood vessel transplantations which has limitations due to lack of donors and the patient's conditions. Although there are several scaffold based studies about vascular tissue engineering, scaffold-based vascular grafts have some side effects including chronic inflammation, thrombosis and rejection after in-vivo implantation. Additionally, there are some problems with cell to cell interaction, the assembly and alignment of ECM components and the host response to scaffolds. Therefore, vascular tissue engineering studies tend towards scaffold-free techniques. In this paper, novel computer aided algorithms and methods are developed for 3D printing of scaffold-free macrovascular structures. An example aorta model is generated using imaging and segmentation software. The developed algorithms are implemented using Rhinoscript. In order to support printed cell aggregates, support structures with 'Cake' and 'Zigzag' patterns are developed and 3D printed

The cientificWorldJOURNAL Clinical Study The Evaluation of Thyroid Diseases in Patients with Pemphigus Vulgaris

Background. Thyroid disorders may affect all of the organ systems of the body and they are also highly associated with a wide variety of skin disorders. The aim of this study was to investigate the prevalence of thyroid function abnormalities and thyroid autoimmunity in patients with pemphigus vulgaris (PV) and to determine the association between thyroid disorders and clinical involvement and systemic corticosteroid treatment in patients with PV. Methods. The study consisted of eighty patients with PV and eighty healthy individuals. Thyroid functions (fT3, fT4, and TSH) and thyroid autoimmunity (anti-thyroid peroxidase (anti-TPO), and anti-thyroglobulin (anti-Tg) antibodies) were investigated in both groups. Primary thyroid disease (PTD) was diagnosed with one or more of the following diagnostic criteria: (i) positive antithyroid antibodies, (ii) primary thyroid function abnormalities. Results. Significant changes in the serum thyroid profile were found in 16% (13/80) of the PV group and 5% (4/80) of the control group. Positive titers of antithyroid antibodies (anti-TPO and anti-Tg) were observed in 7 patients (9%) with PV and one in the control group (1,2%). Hashimoto thyroiditis was diagnosed in 9% of PV patients and it was found to be more prevalent in the mucosal form of PV. PTD was found in 13 of (%16) PV patients which was significantly high compared to controls. PTD was not found to be associated with systemic corticosteroid use. Free T3 levels were significantly lower in PV group compared to the control group and free T4 levels were significantly higher in PV group compared to the controls. Conclusions. PV may exist together with autoimmune thyroid diseases especially Hashimoto thyroiditis and primer thyroid diseases. Laboratory work-up for thyroid function tests and thyroid autoantibodies should be performed to determine underlying thyroid diseases in patients with PV

3D bioprinting of biomimetic aortic vascular constructs with self-supporting cells

Cardiovascular diseases are the leading cause of deaths throughout the world. Vascular diseases are mostly treated with autografts and blood vessel transplantations. However, traditional grafting methods have several problems including lack of suitable harvest sites, additional surgical costs for harvesting procedure, pain, infection, lack of donors and even no substitutes at all. Recently, tissue engineering and regenerative medicine approaches are used to regenerate damaged or diseased tissues. Most of the tissue engineering investigations have been based on the cell seeding into scaffolds by providing a suitable environment for cell attachment, proliferation and differentiation. Because of the challenges such as difficulties in seeding cells spatially, rejection and inflammation of biomaterials used, the recent tissue engineering studies focus on scaffold-free techniques. In this paper, the development of novel computer aided algorithms and methods are developed for 3D bioprinting of scaffold-free biomimetic macrovascular structures. Computer model mimicking a real human aorta is generated using imaging techniques and the proposed computational algorithms. An optimized three-dimensional bioprinting path planning are developed with the proposed self-supported model. Mouse embryonic fibroblast (MEF) cell aggregates and support structures (hydrogels) are 3D bioprinted layer-by-layer according to the proposed self-supported method to form an aortic tissue construct