There are numerous conditions, such as trauma, cancer, congenital malformations, and progressive deforming skeletal diseases, that can compromise the function and architectonics of bones of ...craniofacial region. The need to develop new approaches for treatment of these disorders arises from the fact that conventional therapeutic strategies face many obstacles and limitations. The use of tissue engineering in regeneration of craniofacial bone structures is a very promising possibility and a great challenge for researchers and practitioners. Developments in stem cell biology and engineering have led to the discovery of different stem cell populations and biodegradable materials with suitable properties. This review summarizes the current achievements in tissue engineering of craniofacial bone, temporomandibular joint, and periodontal ligament.
The development of biological and biomaterial sciences profiled tissue engineering as a new and powerful tool for biological replacement of organs. The combination of stem cells and suitable ...scaffolds is widely used in experiments today, in order to achieve partial or whole organ regeneration. This review focuses on the use of tissue engineering strategies in tooth regeneration, using stem cells and stem cells/scaffold constructs. Although whole tooth regeneration is still not possible, there are promising results. However, to achieve this goal, it is important to understand and further explore the mechanisms underlying tooth development. Only then will we be able to mimic the natural processes with the use of stem cells and tissue engineering techniques.
With the increasing constraints set by the European Commission to reduce Carbon dioxide and nitrogen oxide/dioxide emissions, the aerospace industry is attempting to combat this issue by increasing ...the utilisation of advanced composite materials. However, the transition from metal alloys to advanced composites on primary or secondary structures as well as propulsion jet engines does not come without its challenges, one of which is the impact performance of carbon fibre-epoxy composites. The aim of this work is to improve the impact performance of composite by developing novel, complex and sophisticated fibre architectures where the crack propagation within composite laminates is more difficult. This process is called interleaving and it is carried out using an automated deposition technique called Automated Fibre Placement (AFP). An AFP deposition head deposits strips of pre-impregnated carbon fibre-epoxy tapes and does so using independent feed and cut mechanisms. By selecting which tapes are active during the deposition process, it is possible to create an interleaved fibre architecture. As not all the available tapes are deposited by the AFP head in order to create an interleaved fibre architecture, the manufacturing performance is impacted with the simplest interleaved fibre architecture requiring double the deposition time (compared to a standard AFP laminate), while the most complex interleaved fibre architecture explored in the project requires quadruple the deposition time (compared to a standard AFP laminate). Within this thesis conventional Design Principles, Concepts, and Solutions are used to develop the Interleaved Laminates, and from these developments three levels of Interleaving are chosen for manufacturing and physio-mechanical assessment. Three different material types are used in order to evaluate any effects of material and processing properties on the interleaved laminates (structure versus property concerns); with more traditional AFP laminates produced and mechanically assessed in the same testing regime, to act as appropriate baselines for any performance evaluation. The Interleaved Laminates are evaluated in their Tensile, Compressive, Mode I Fracture Toughness, Mode II Fracture Toughness, Flexural and Combined Through thickness Compression/Shear properties, where all the levels of Interleaved laminates are compared to a standard AFP laminate. Unfortunately there was no impact testing completed within this study, as it was determined that to understand the changes in fundamental mechanical properties was more important at this stage, before moving forward to more complex failure modes such as high strain rate impact. From the analysis of the mechanical testing carried out, it was found that it is possible to obtain an improvement of 23.3% in Mode I Fracture Toughness and 34.9% in Mode II Fracture Toughness for a specific structural and material configuration. These improvements are achievable at the expense of Tensile properties of 9.8% for the Mode I Fracture Toughness improvements and 7.1% for the Mode II Fracture Toughness improvements. It is broadly concluded that for design cases where Mode I and Mode II Fracture Toughness are the limiting factor, interleaving is a suitable and beneficial alternative for conventional laminates. However, in design cases where tensile (and for some configurations compressive) properties are the limiting factor, Interleaving is not most suitable manufacturing method.
Cardiovascular repair and myocardial contractility may be improved by migration of bone marrow stem cells (BMSC) and their delivery to the site of injury, a process known as BMSC homing. The aim of ...our study was to examine the dietary effect of a newly patented depurinized milk (DP) that is almost free of uric acid and purine and pyrimidine compounds compared with a standard commercial 1.5% fat UHT milk diet or allopurinol therapy in rat experimental hyperuricemia. Bone marrow stem cell potential (BMCD34+, CD34-postive bone marrow cells), plasma oxidative stress parameters advanced oxidation protein products, AOPP) and thiobarbituric acid reactive substances (TBARS), myocardial damage markers creatine phosphokinase (CPK), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH), plasma cholesterol, and high-density lipoprotein cholesterol were investigated. The DP milk diet significantly increased the number of BMCD34+ stem cells compared with commercial UHT milk. Allopurinol given alone also increased the number of BMCD34+. Hyperuricemia caused a significant increase in all plasma enzyme markers for myocardial damage (CPK, LDH, and AST). A cardioprotective effect was achieved with allopurinol but almost equally with DP milk and more than with commercial milk. Regarding plasma AOPP, TBARS, and cholesterol levels, the most effective treatment was DP milk. In conclusion, the protective role of a milk diet on cardiovascular function may be enhanced through the new depurinized milk diet, which may improve cardiovascular system function via increased bone marrow stem cell regenerative potential, decreased plasma oxidative stress parameters, and decreased levels of myocardial damage markers and cholesterol. New dairy technology strategies focused on eliminating harmful milk compounds should be completely nontoxic. Novel milk products should be tested for their ability to improve tissue repair and function.
Religion influences people and their perceptions. This paper examines Muslim hosts' perception of Western mass tourism using the tourist island of Gili Trawangan in Indonesia. The study's primary ...purpose is to show how the beliefs and practices of the Islamic religion of the local community influence the perception of the impacts of tourism. A quantitative method was employed among locals. The results show a certain tolerance and acceptance of Western tourism by the local Muslim community, characterized as having a strong religious belief and a practice level that varies from one individual to another.
The aim of the investigations was to check the behaviour of Al-Zn-Sn aluminium cast alloys with additions of bismuth and gallium for potential application as a material for protecting protectors. The ...chemical composition, the mechanical characteristics, the microstructure and the corrosion properties were investigated. Particular attention was given to microstructural investigations aimed to identify the phases that might have an active role for corrosion in chloride solution. Three corrosion tests were used: change in the corrosion potential with time, determination of the values for polarisation resistance and the corrosion current, and potentio-dynamic recording of the cathode and anode polarisation curves.
Binuclear {Pd (dien)}2(μ‐pz)(ClO4)4 (Pd1) and {Pd (dien)}2(μ‐pydz)(ClO4)4 (Pd2) complexes, where pz is 1,4‐diazine and pydz is 1,2‐diazine bridging ligands and dien (diethylenetriamine) is a ...tridentately coordinated triamine ligand, were synthesized and characterized using elemental analysis, NMR (1H and 13C) spectroscopy, and UV–Vis spectrophotometry. Electronic absorption spectrophotometry and fluorescence spectroscopy were used to study the interactions of the prepared Pd1 and Pd2 complexes with deoxyribonucleic acid (CT‐DNA) and bovine serum albumin (BSA). According to the UV–Vis spectrophotometric data, the complexes interact with CT‐DNA and bind to the BSA as a possible carrier to the target site. The antitumor properties of the tested palladium compounds were evaluated on three types of human cancer cells, namely, squamous cell carcinoma cells SCC‐4, cervical carcinoma cells HeLa and colorectal carcinoma cells HCT116, and one type of malignantly unchanged cells, MRC‐5 fibroblasts. The highest cytotoxicity was shown by the Pd1 compound against SCC‐4 cell, with an IC50 value of 5.4 ± 1.2 μM. The results showed that the cytotoxic potential against SCC‐4 cells of our new palladium complexes Pd1 and Pd2 was comparable with the cytotoxic potential of cisplatin and oxaliplatin. However, Pd1 and Pd2 displayed significantly lower cytotoxicity in comparison with cisplatin and oxaliplatin against non‐malignant cells, fibroblasts MRC5, so these results may suggest that local and systemic complications of antitumor therapy could be reduced and/or avoided. Both compounds selectively decreased the viability of SCC‐4 cells by induction of apoptosis. Also, Pd1 and Pd2 induced S‐phase cell cycle arrest in human SCC‐4 cells, so that could be another mechanism to halt the uncontrolled growth and division of cancer cells. Moreover, the precise molecular mechanism of Pd1 and Pd2 complexes‐induced apoptosis was the activation of the intrinsic signaling pathway of apoptosis, which also included activation of caspase‐3. Therefore, our new palladium (II) complexes might have a promising role as the potential future cytostatic agents.
Pd1 and Pd2 selectively decrease the viability of cancer cells via cell cycle arrest and activation of caspase‐dependent mitochondrial apoptotic pathway.
Less invasive coronary artery bypass grafting surgery is underused despite more than 25 years of interest from surgeons and growing patient demands for less pain and rapid full recovery. New ...approaches may offer surgeons additional options to provide enhanced clinical results through reliable subxiphoid bilateral internal thoracic artery harvesting and the creation of durable anastomoses through very small thoracotomy incisions. This first-in-human case report describes 2 patients who received surgical coronary revascularization using the µCAB™ technology and techniques. The encouraging early results indicate that the µCAB™ approach may offer a new ergonomic, affordable method for coronary revascularization with less surgical trauma.
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