Design and Characterization of a Novel Knee Articulation Mechanism

Abstract The paper is focused on designing a novel controllable and adjustable mechanism for reproducing human knee joint's complex motion by taking into account the flexion/extension movement in the sagittal plane, in combination with roll and slide. Main requirements for a knee rehabilitation supporting device are specified by researching the knee's anatomy and already existing mechanisms. A three degree of freedom (3 DOF) system (four-bar like linkage with controlled variable lengths of rockers) is synthesised to perform the reference path of instantaneous centre of rotation (ICR). Finally, a preliminary design of the adaptive mechanism is elaborated and a numerical model is built in Adams. Numerical results are derived from simulations that are presented to evaluate the accuracy of the reproduced movement and the mechanism's capabilities

The behavior of osteoblast-like cells on various substrates with functional blocking of integrin-β1 and integrin-β3

This study was designed to examine the influence of integrin subunit-β1 and subunit-β3 on the behavior of primary osteoblast-like cells, cultured on calcium phosphate (CaP)-coated and non coated titanium (Ti). Osteoblast-like cells were incubated with specific monoclonal antibodies against integrin-β1 and integrin-β3 to block the integrin function. Subsequently, cells were seeded on Ti discs, either non coated or provided with a 2 μm carbonated hydroxyapatite coating using Electrostatic Spray Deposition. Results showed that on CaP coatings, cellular attachment was decreased after a pre-treatment with either anti-integrin-β1 or anti-integrin-β3 antibodies. On Ti, cell adhesion was only slightly affected after a pre-treatment with anti-integrin-β3 antibodies. Scanning electron microscopy showed that on both types of substrate, cellular morphology was not changed after a pre-treatment with either antibody. With quantitative PCR, it was shown for both substrates that mRNA expression of integrin-β1 was increased after a pre-treatment with either anti-integrin-β1 or anti-integrin-β3 antibodies. Furthermore, after a pre-treatment with either antibody, mRNA expression of integrin-β3 and ALP was decreased, on both types of substrate. In conclusion, osteoblast-like cells have the ability to compensate to great extent for the blocking strategy as applied here. Still, integrin-β1 and β3 seem to play different roles in attachment, proliferation, and differentiation of osteoblast-like cells, and responses on CaP-coated substrates differ to non coated Ti. Furthermore, the influence on ALP expression suggests involvement of both integrin subunits in signal transduction for cellular differentiation

Eculizumab treatment: stochastic occurrence of C3 binding to individual PNH erythrocytes

C5 blockade by eculizumab prevents complement-mediated intravascular hemolysis in paroxysmal nocturnal hemoglobinuria (PNH). However, C3-bound PNH red blood cells (RBCs), arising in almost all treated patients, may undergo extravascular hemolysis reducing clinical benefits. Despite the uniform deficiency of CD55 and of CD59, there are always two distinct populations of PNH RBCs, with (C3+) and without (C3-) C3 binding

Stage-Specific Changes in Plasmodium Metabolism Required for Differentiation and Adaptation to Different Host and Vector Environments

Malaria parasites (Plasmodium spp.) encounter markedly different (nutritional) environments during their complex life cycles in the mosquito and human hosts. Adaptation to these different host niches is associated with a dramatic rewiring of metabolism, from a highly glycolytic metabolism in the asexual blood stages to increased dependence on tricarboxylic acid (TCA) metabolism in mosquito stages. Here we have used stable isotope labelling, targeted metabolomics and reverse genetics to map stage-specific changes in Plasmodium berghei carbon metabolism and determine the functional significance of these changes on parasite survival in the blood and mosquito stages. We show that glutamine serves as the predominant input into TCA metabolism in both asexual and sexual blood stages and is important for complete male gametogenesis. Glutamine catabolism, as well as key reactions in intermediary metabolism and CoA synthesis are also essential for ookinete to oocyst transition in the mosquito. These data extend our knowledge of Plasmodium metabolism and point towards possible targets for transmission-blocking intervention strategies. Furthermore, they highlight significant metabolic differences between Plasmodium species which are not easily anticipated based on genomics or transcriptomics studies and underline the importance of integration of metabolomics data with other platforms in order to better inform drug discovery and design

Therapeutic Touch and Cancer Cells

Energy medicine therapies based on a human biofield have been practiced for thousands of years and can trace their origin in Ayurveda. Our goal was to determine if Therapeutic Touch (TT), a more recently developed energy medicine practice, had any effects on cancer cells. Previous work in our laboratory demonstrated that TT significantly increased the growth of normal human osteoblasts and increased the synthesis of bone matrix proteins and mineralization in cell culture. In this study as was practiced in our previous studies, TT was performed twice a week for 10 minutes and was compared to untreated cultures and \u27placebo-treated cultures. Two different cell lines of human bone cancer, osteosarco~a, were used; Saos-2 and HOS, derived from different patients. TT significantly (p=O.01) decreased HOS proliferation determined by radioactive thymidine incorporation into the DNA, but had no significant effect on Saos-2 cells compared to untreated control and placebo-treated groups. At 2 weeks, TT significantly decreased mineralization, determined by assaying calcium content of the cell layer of Saos-2 and HOS cells (p=O.03), compared to control and placebo-treated cultures. Additionally, Northem blot analysis indicated a TT-induced decrease in mRNA expression for several bone matrix proteins in both Saos-2 and HOS cell cultures. In conclusion, Therapeutic Touch decreased differentiation and bone formation in human osteosarcoma-derived cells and significantly decreased cell growth in the HOS but not in Saos-2 cells. These results demonstrate that a human biofield exists, which is able to affect cell activities and may have therapeutic value in patients

Design and Simulations of Wheel-Legged Mobile Robot

The problems of determining dynamic and kinematic parameters of wheel-legged mobile robot were considered in the paper. The numerical computer model of robot was worked out and simulation researches of suspension were completed. The motion of wheel on road with obstacles and walking motion of wheel were analyzed for determining kinematic and dynamic parameters