Impact of five floor coverings on the orthostatic balance of healthy subjects

Plantar skin sensitivity contributes to the regulation of postural control and, therefore, changing the characteristics of the plantar support surface can modify this control. This study aimed at assessing the impact of five different floor coverings on the orthostatic balance in 48 healthy subjects. Static posturography was performed with eyes open or closed on a platform in a control condition (no covering) and with five different covering surfaces: foam, silicone, ethyl vinyl acetate, and two textured mats with small (height 2 mm) or large pimples (7 mm). The average velocity of center of pressure (CoP) displacement was the primary endpoint measure and ten other posturographic variables were assessed. Comfort and pain produced by the covering were also scored. In eyes open condition, the average velocity of CoP displacement was increased when subjects stood on the foam mat, the silicone mat, and especially the textured mat with large pimples. Several other posturographic variables showed significant changes with different types of floor coverings with eyes open. These changes were not correlated to the comfort or pain scores associated with the different surfaces. In contrast, no difference was observed compared to the control condition (no covering) with eyes closed. This study shows that adding smooth or textured floor covering can alter balance in eyes open condition. In eyes closed condition, although more disturbing for balance, healthy subjects achieved better postural adaptation, probably by mobilizing more of their proprioceptive resources. This posturographic examination procedure could, therefore, be used to assess "proprioceptive reserve" capacities in clinical practice.

Inhibition of bacterial adhesion and biofilm formation by a textured fluorinated alkoxyphosphazene surface

The utilization of biomaterials in implanted blood-contacting medical devices often induces a persistent problem of microbial infection, which results from bacterial adhesion and biofilm formation on the surface of biomaterials. In this research, we developed new fluorinated alkoxyphosphazene materials, specifically poly[bis(octafluoropentoxy) phosphazene] (OFP) and crosslinkable OFP (X-OFP), with improved mechanical properties, and further modified the surface topography with ordered pillars to improve the antibacterial properties. Three X-OFP materials, X-OFP3.3, X-OFP8.1, X-OFP13.6, with different crosslinking densities were synthesized, and textured films with patterns of 500/500/600 nm (diameter/spacing/height) were fabricated via a two stage soft lithography molding process. Experiments with 3 bacterial strains: Staphylococcal epidermidis, Staphylococcal aureus, and Pseudomonas aeruginosa showed that bacterial adhesion coefficients were significantly lower on OFP and X-OFP smooth surfaces than on the polyurethane biomaterial, and surface texturing further reduced bacterial adhesion due to the reduction in accessible surface contact area. Furthermore the anti-bacterial adhesion effect shows a positive relationship with the crosslinking degree. Biofilm formation on the substrates was examined using a CDC biofilm reactor for 7 days and no biofilm formation was observed on textured X-OFP biomaterials. The results suggested that the combination of fluorocarbon chemistry and submicron topography modification in textured X-OFP materials may provide a practical approach to improve the biocompatibility of current biomaterials with significant reduction in risk of pathogenic infection.

Biomechanical analysis of single-leg stance using a textured balance board compared to a smooth balance board and the floor: A cross-sectional study

BACKGROUND

Previous research showed that standing on textured surfaces can improve postural control by adapting somatosensory inputs from the plantar foot. The additional stimulation of plantar cutaneous mechanoreceptors by a textured surface during single-leg stance on a balance board may increase afferent information to the central nervous system to accelerate muscular responses and to enhance their accuracy. The additional impact of textured surface during single-leg stance on a balance board on postural control and muscle activity is unknown.

RESEARCH QUESTION

To investigate the differences of a) postural control during single-leg stance on a textured balance board compared to a smooth balance board and b) activity of lower extremity muscles during single-leg stance on a textured balance board compared to a smooth balance board and the floor.

METHODS

Twenty-six healthy adults (12 females, 14 males; mean age = 25.4 years) were asked to balance on their randomly assigned left or right leg on a force plate (floor; stable condition), a textured balance board and a smooth balance board (unstable conditions). Center of pressure (CoP) displacements (force plate, Bertec, 1000 Hz) and electromyographic activity (EMG) of eight leg muscles were measured and compared between conditions, respectively.

RESULTS

Neither CoP-displacements, nor EMG activities differed significantly between the textured and the smooth balance board (p > 0.05). Significantly higher muscle activities (p < 0.05) were observed using the balance boards compared to the floor.

SIGNIFICANCE

Single-leg stance using a textured balance board seems not to lead to reduced CoP-displacements compared to a smooth balance board. Muscle activation is significantly increased in both balance board conditions compared to the floor, however, it is not different when both balance board surfaces are compared. It could not be recommended to use a textured balance board for altering muscle activity and improving postural control during single-leg stance in favor of a smooth textured balance board.

Spreading of biologically relevant liquids over the laser textured surfaces

HYPOTHESIS

The distribution of biological objects upon the spreading of biologically relevant dispersions over laser textured surfaces is affected by the dispersion composition and substrate chemistry and roughness.

EXPERIMENTS

To examine the role of the substrate texture in biologically relevant liquid spreading, the dynamic behavior of droplets of water and dispersions of bacterial cells and viruses and dynamic behavior of droplet/air surface tension were addressed. A new procedure to simultaneously distinguish three different spreading fronts was developed.

FINDINGS

The study of spreading of water and the biologically relevant liquids over the laser textured substrate indicate the development of three spreading fronts associated with the movement of bulk droplet base, the flow along the microchannels, and the nanotexture impregnation. The anisotropy of spreading for all types of liquid fronts was found. Despite the expected difference in the rheological behavior of water and the biologically relevant liquids, the spreading of all tested liquids was successfully described by power-law fits. The droplet base spreading for all tested liquids followed the Tanner law. The advancing of water and dispersions in the microchannels along both fast and slow axes was described by Washburn type behavior. The impregnation of the nanotexture by water and biologically relevant liquids demonstrated universality in power fit description with an exponent n = 0.23.

Breast implant-associated anaplastic large-cell lymphoma: first case detected in a Japanese breast cancer patient

This paper details the first breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL) case detected in Japan. The patient, a 67-year-old Japanese woman, was diagnosed with left unilateral breast cancer 17 years ago. Induration and redness presented in the left breast, which had undergone immediate breast reconstructive surgery using a tissue expander, later replaced by a silicone breast implant (SBI). Breast ultrasound showed fluid collection around the SBI. Surgery was performed to remove the left breast implant and the fragmented capsule surrounding the implant. Postoperative pathological findings did not indicate malignancy. Nine months later, a contralateral axillary lymphadenopathy was observed, and an excisional biopsy of the axillary lymph node was performed. The patient was diagnosed with BIA-ALCL and successfully underwent adjuvant CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) chemotherapy.

Novel thin-GaN LED structure adopted micro abraded surface to compare with conventional vertical LEDs in ultraviolet light

In this study, novel thin-GaN-based ultraviolet light-emitting diodes (NTG-LEDs) were fabricated using wafer bonding, laser lift-off, dry etching, textured surface, and interconnection techniques. Placing PN electrodes on the same side minimized the absorption caused by electrodes in conventional vertical injection light-emitting diodes (V-LEDs) and the current spreading was improved. The light output power (700 mA) of the NTG-LEDs was enhanced by 18.3% compared with that of the V-LEDs, and the external quantum efficiency (EQE) of the NTG-LEDs was also relatively enhanced by 20.0% compared with that of a reference device. When the current operations were 1,500 mA, the enhancements of the light output power and EQE were 27.4% and 27.2%, respectively. Additionally, the efficiency droop was improved by more than 15% at the same current level.