Search results for "Biophysic"
showing 10 items of 3565 documents
Haliotis tuberculata hemocyanin (HtH): analysis of oligomeric stability of HtH1 and HtH2, and comparison with keyhole limpet hemocyanin KLH1 and KLH2
2000
The multimeric/higher oligomeric states of the two isoforms of Haliotis tuberculata hemocyanin (HtH1 and HtH2) have been assessed by transmission electron microscopy (TEM) of negatively stained specimens, for comparison with previously published structural data from keyhole limpet hemocyanin (KLH1 and KLH2) [see Harris, J.R., Gebauer, W., Guderian, F.U., Markl, J., 1997a. Keyhole limpet hemocyanin (KLH), I: Reassociation from Immucothel followed by separation of KLH1 and KLH2. Micron, 28, 31-41; Harris, J.R., Gebauer, W., Söhngen, S.M., Nermut, M.V., Markl, J., 1997b. Keyhole limpet hemocyanin (KLH). II: Characteristic reassociation properties of purified KLH1 and KLH2. Micron, 28, 43-56; H…
Production and characterization of the recombinant Sphingomonas chlorophenolica pentachlorophenol 4-monooxygenase.
2001
Abstract Pentachlorophenol 4-monooxygenase (PCP4MO) from Sphingomonas chlorophenolica is a flavoprotein that hydroxylates PCP in the presence of NADPH and oxygen. In order to investigate the structure and function of active site, recombinant PCP4MO (rePCP4MO) was produced in Escherichia coli as a glutathione S-transferase (GST) fusion protein. Moreover, a tobacco etch virus (TEV) protease cleavage site (EKLYFQG) was introduced into GST-PCP4MO and a his-tagged TEV protease was employed. Hence, a two-step purification protocol was developed which allowed obtaining 15–20 mg of rePCP4MO from 1 L culture. The rePCP4MO revealed identity with native enzyme by SDS–PAGE and N-terminal sequence analy…
Actual and Perceived Motor Competence, Cardiorespiratory Fitness, Physical Activity, and Weight Status in Schoolchildren : Latent Profile and Transit…
2022
Engagement in physical activity plays a central role in the prevention and treatment of childhood overweight/obesity. However, some children may lack the skills and confidence to be physically active. This 3-year follow-up study aimed to form profiles based on cardiorespiratory fitness, actual motor competence, perceived motor competence, physical activity, and weight status, and to examine if these profiles remain stable from late childhood to early adolescence. All these variables were annually assessed in 1,162 Finnish schoolchildren (girls = 583 and boys = 564, Mage = 11.27 ± 0.32 years). Latent profile analysis was used to identify profiles and latent transition analysis to examine the…
ShRNA-mediated knock-down of CXCL8 inhibits tumor growth in colorectal liver metastasis.
2018
CXCL8 belongs to proinflammatory chemokines that are predominantly involved in neutrophil chemotaxis and degranulation. Several studies have suggested that secretion of CXCL8 from cancer cells have a profound effect on tumor microenvironment. In this study, in continuation to our previous work of understanding the global picture of invasion related genes in colorectal liver metastases, we clearly show an up-regulation of CXCL8 expression in the tumor cells at the invasion front as compared to the tumor cells in the inner parts of the tumor. Furthermore, ShRNA mediated down-regulation of CXCL8 resulted in inhibition of cell proliferation, viability and invasion in vitro and a near complete g…
An approach to a biomimetic bone scaffold: increased expression of BMP-2 and of osteoprotegerin in SaOS-2 cells grown onto silica-biologized 3D print…
2012
Three-dimensional printed (3D printed) bone material is needed to close the shortage and to avoid the potential health risks associated with autografts and allografts, in the treatment of bone fractures/nonunions or bone trauma. Here we describe the fabrication of 3D printed scaffold, initially prepared form Ca-sulfate that has been impregnated/biologized with Ca-phosphate or with silica. The 3D printed grids had a size mesh of 200 μm; the chemical composition was determined by energy dispersive X-ray spectroscopy or conventional chemical analysis. Using human SaOS-2 cells (human osteogenic cells) it is shown that both the Ca-sulfate, and the Ca-phosphate or the silica impregnated Ca-sulfat…
Individual muscle contributions to the in vivo achilles tendon force
1998
OBJECTIVE: To ascertain the possibility of non-uniform stress within the achilles tendon due to individual force contributions of the triceps surae. DESIGN: Calculation of non-uniform stress through discrepancies in moments about the ankle joint. BACKGROUND: Non-uniform stress over the cross-sectional area have been implied in the etiology of achilles tendon injury and may influence functional aspects. However, this has not been empirically demonstrated. METHODS: In vivo achilles tendon forces were measured with an optic fibre technique during isometric plantarflexions at systematically varied knee angles and contraction intensities. A comparison to the plantar force measured underneath the…
Movement Variability Increases With Shoulder Pain When Compensatory Strategies of the Upper Body Are Constrained
2017
[DE] This cross-sectional study analyzed the influence of chronic shoulder pain (CSP) on movement variability/kinematics during humeral elevation, with the trunk and elbow motions constrained to avoid compensatory strategies. For this purpose, 37 volunteers with CSP as the injured group (IG) and 58 participants with asymptomatic shoulders as the control group (CG) participated in the study. Maximum humeral elevation (Emax), maximum angular velocity (Velmax), variability of the maximum angle (CVEmax), functional variability (Func_var), and approximate entropy (ApEn) were calculated from the kinematic data. Patients' pain was measured on the visual analogue scale (VAS). Compared with the CG, …
Biomechanical testing of different posterior fusion devices on lumbar spinal range of motion.
2019
Abstract Background Recent minimal-invasive posterior fusion devices are supposed to provide stability and obtain fusion in combination with interbody cages in the instrumented segment. The aim of the present study is to evaluate the primary stability of two minimal-invasive posterior prototypes compared to an established spinous process plate and standard pedicle screw instrumentation. Methods Seven fresh frozen human cadaver lumbar spines (L2–L5) were tested in a spinal testing device with a moment of 7.5 Nm. Spinal stability was determined as mean range of motion (RoM) in the segment L3/L4 during extension-flexion, lateral bending and axial rotation. The RoM was measured during five cond…
Correlation of Tibial Low-Frequency Ultrasound Velocity with Femoral Radiographic Measurements and BMD in Elderly Women
2009
The ultrasonic axial transmission technique has been proposed as a method for cortical bone characterization. Using a low enough center frequency, Lamb modes can be excited in long bones. Lamb waves propagate throughout the cortical bone layer, which makes them appealing for characterizing bone material and geometrical properties. In the present study, a prototype low-frequency quantitative ultrasonic axial transmission device was used on elderly women (n = 132) to investigate the relationships between upper femur geometry and bone mineral density (BMD) and tibial speed of sound. Ultrasonic velocities (V) were recorded using a two-directional measurement set-up on the midtibia and compared …
The role of biosilica in the osteoprotegerin/RANKL ratio in human osteoblast-like cells
2010
Abstract Earlier studies have demonstrated that biosilica, synthesized by the enzyme silicatein, induces hydroxyapatite formation in osteoblast-like SaOS-2 cells. Here we study the effect of biosilica on the expressions of osteoprotegerin [OPG] and the receptor activator for NF-κB ligand [RANKL] in the SaOS-2 cell model. We show that during growth of SaOS-2 cells on biosiliceous matrices hydroxyapatite formation is induced, while syntheses of cartilaginous proteoglycans and sulfated glycosaminoglycans are down-regulated. Furthermore, quantitative real-time RT-PCR analysis revealed a strong time-depended increase in expression of OPG in biosilica exposed SaOS-2 cells while the steady-state e…