Current Issue : April - June Volume : 2020 Issue Number : 2 Articles : 5 Articles
Background: The design freedom allowed by three-dimensional (3D) printing enables the production of acetabular\noff-the-shelf cups with complex porous structures. The only studies on these designs are limited to clinical outcomes.\nOur aim was to analyse and compare the designs of different 3D printed cups from multiple manufacturers (Delta TT,\nTrident II Tritanium and Mpact 3D Metal).\nMethods: We analysed the outer surface of the cups using scanning electron microscopy (SEM) and assessed clinically\nrelevant morphometric features of the lattice structures using micro-computed tomography (micro-CT). Dimensions\nrelated to the cup wall (solid, lattice and overall thickness) were also measured. Roundness and roughness of the internal\ncup surface were analysed with coordinate measuring machine (CMM) and optical profilometry.\nResults: SEM showed partially molten titanium beads on all cups, significantly smaller on Trident II (27 microm vs approximately70 microm,\np < 0.0001). We found a spread of pore sizes, with median values of 0.521, 0.841 and 1.004mm for Trident II, Delta TT\nand Mpact, respectively. Trident II was also significantly less porous (63%, p < 0.0001) than the others (Delta TT 72.3%,\nMpact 76.4%), and showed the thinnest lattice region of the cup wall (1.038 mm, p < 0.0001), while Mpact exhibited the\nthicker solid region (4.880 mm, p < 0.0044). Similar roundness and roughness of the internal cup surfaces were found.\nConclusion: This was the first study to compare the designs of different 3D printed cups. A variability in the morphology\nof the outer surface of the cups and lattice structures was found. The existence of titanium beads on 3D printed parts is a\nknown by-product of the manufacturing process; however, their prevalence on acetabular cups used in patients is an\ninteresting finding, since these beads may potentially be released in the body....
Background: Triple tracer meal experiments used to investigate organ glucose-insulin dynamics, such as\nendogenous glucose production (EGP) of the liver are labor intensive and expensive. A procedure was developed to\nobtain individual liver related parameters to describe EGP dynamics without the need for tracers.\nResults: The development used an existing formula describing the EGP dynamics comprising 4 parameters defined\nfrom glucose, insulin and C-peptide dynamics arising from triple meal studies. The method employs a set of partial\ndifferential equations in order to estimate the parameters for EGP dynamics. Tracer-derived and simulated data sets\nwere used to develop and test the procedure. The predicted EGP dynamics showed an overall mean R2 of 0.91.\nConclusions: In summary, a method was developed for predicting the hepatic EGP dynamics for healthy,\npre-diabetic, and type 2 diabetic individuals without applying tracer experiments....
Mesenchymal stem cells have been widely implicated in tumour development and\nmetastases. Moving from the use of two-dimensional (2D) models to three-dimensional (3D) to\ninvestigate this relationship is critical to facilitate more applicable and relevant research on the tumour\nmicroenvironment. We investigated the effects of altering glucose concentration and the source of\nfoetal bovine serum (FBS) on the growth of two breast cancer cell lines (T47D and MDA-MB-231)\nand human bone marrow-derived mesenchymal stem cells (hBM-MSCs) to determine successful\nconditions to enable their co-culture in 3D tumour spheroid models. Subsequently, these 3D\nmulti-cellular tumour spheroids were used to investigate the effect of hBM-MSCs on breast cancer\ncell invasiveness. Findings presented herein show that serum source had a statistically significant\neffect on two thirds of the growth parameters measured across all three cell lines, whereas glucose\nonly had a statistically significant effect on 6%. It was determined that the optimum growth media\ncomposition for the co-culture of 3D hBM-MSCs and breast cancer cell line spheroids was 1 g/L\nglucose DMEM supplemented with 10% FBS from source A. Subsequent results demonstrated that\nco-culture of hBM-MSCs and MDA-MB-231 cells dramatically reduced invasiveness of both cell lines\n(F(1,4) = 71.465, p = 0.001) when embedded into a matrix comprising of growth-factor reduced base\nmembrane extract (BME) and collagen....
Microfluidic-based technology attracts great interest in cell biology and medicine, in virtue\nof the ability to better mimic the in vivo cell microenvironment compared to conventional macroscale\ncell culture platforms. Recent Organs-on-chip (OoC) models allow to reproduce in vitro tissue\nand organ-level functions of living organs and systems. These models have been applied for the\nstudy of specific functions of the female reproductive tract, which is composed of several organs\ninterconnected through intricate endocrine pathways and communication mechanisms. To date,\na disease and toxicology study of this system has been difficult to perform. Thus, there is a compelling\nneed to develop innovative platforms for the generation of disease model and for performing drug\ntoxicity/screening in vitro studies. This review is focused on the analysis of recently published OoC\nmodels that recreate pathological and physiological characteristics of the female reproductive organs\nand tissues. These models aim to be used to assess changes in metabolic activity of the specific cell\ntypes and the effect of exposure to hormonal treatment or chemical substances on some aspects of\nreproduction and fertility. We examined these models in terms of device specifications, operating\nprocedures, accuracy for studying the biochemical and functional activity of living tissues and the\nparacrine signalling that occurs within the different tissues. These models represent a powerful tool for\nunderstanding important diseases and syndromes affecting women all around the world. Immediate\nadoption of these models will allow to clarify diseases, causes and adverse events occurring during\npregnancy such as pre-eclampsia, infertility or preterm birth, endometriosis and infertility....
Background: Xenogeneic bone has been widely used in a variety of clinical bonerelated\ndisease to promote bone healing and restore bone defects. However, the\nadverse effects of immune system limit its application in the clinic. The aim of this\nstudy was to evaluate xenogeneic bone safety of immunotoxicity and explore the\nmethods for immune risk supervision.\nResults: Xenogeneic bone, which is freeze-dried bovine cancellous bone, was\nimplanted into the muscle of mice. On day 7, 14 and 28, the effects of xenogeneic\nbone were examined on humoral immunity and cellular immunity, including the levels\nof IgG, IgM, C3, inflammatory factors (TNF-a, IL-6), alkaline phosphatase (ALP) and the\nlymphocyte phenotype. The data showed that xenogeneic bone implantation had\nno potential to induce immune responses not only in humoral immunity but also\nin cellular immunity. To reveal the risk of immunogenicity, the residual DNA and the\nclearance of a-gal epitope were analyzed in 2 different bones (bone 1 is deproteinized\nbone, bone 2 is acellular and defatted bone). It was suggested that DNA of xenogeneic\nbone can be limited to < 50 ng per mg dry weight for the repair or regeneration with\nthe acceptable immune risk. And a-gal clearance of xenogeneic bone could be an\neffective risk factor for improving xenograft quality management.\nConclusions: Through the detection of xenogeneic bone immunotoxicity, our findings\nindicated that the supervisions of risk factors could contribute to reduce the\nimmune risk. And the risk factors under the acceptable limitation could decrease or\nreplace animal experiment. However, it still needs to be studied on the limitation of\na-gal epitope to predict rejection of xenogeneic bone more accurately....
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