Non-thermal plasma radiation-induced changes in antibiotic susceptibility and protein profile of Staphylococcus aureus.

Background and Objectives: Plasma radiation is a widely used technique for sterilization or decontamination in various industries, as well as in some healthcare settings such as dentistry. The primary aim of this study was to assess the potential of plasma radiation to create a new population of Staphylococcus aureus cells with distinct characteristics that could lead to novel healthcare challenges. Materials and Methods: A homemade non-thermal plasma apparatus was applied and the effects of plasma treatment on S. aureus ATCC25923 was assessed. Plasma radiation was applied under controlled conditions to ensure that some bacterial cells remained viable. The treatment was repeated 10 times, with each round followed by a recovery phase to collect any surviving bacterial cells. To assess the potential changes in the bacterial population, we examined the antibiotic susceptibility pattern, micro-structural characteristics using scanning electron microscopy (SEM), and total protein profile using the matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) technique. Results: The experimental results revealed slight variations in the antibiotic susceptibility patterns of certain cell wall agents (imipenem, cephalothin, and cefepime), as well as in the MALDI-TOF spectra. However, no changes were observed in the SEM images. Conclusion: The insufficient application of non-thermal plasma in bacterial decontamination may lead to physiological changes that could enrich or select certain subpopulations of S. aureus.

The effect of toe-only rocker sole shoes on gait variability of the elderly.

Gait variability could associate with fall risk in older people. Rocker sole shoes are commonly prescribed to reduce plantar pressure and facilitate forward movement. Thus, it may affect gait stability. The purpose of this study was to investigate the effects of toe-only rocker shoes on gait variability in the elderly. Seventeen healthy elderly participants walked on a treadmill under six different conditions including barefoot (BF), normal shoe (NS), and four types of toe-only rocker sole shoes with various degrees of rocker angle (RS10, RS20, RS30, and RS40). Then the step length variability (SLV), the step time variability (STV), the step width variability (SWV), and the stance time variability were measured. Increasing rocker angle in toe-only rocker did not significantly affect gait variability more than the standard shoe. It seems that different rocker angles in toe-only rocker sole shoes do not pose a threat to gait variability compared to the standard shoes in healthy elderly. Findings of the study suggested that the toe-only rocker sole can be used to facilitate forward progression in the elderly. Further investigation is also required to examine the long-term effects of toe-only rocker sole shoes on gait variability in frail elderly.

In vivo study of the effects of a portable cold plasma device and vitamin C for skin rejuvenation.

Nowadays, cold atmospheric plasma shows interesting results in dermatology. In the present study, a new portable cold plasma was designed for plasma skin rejuvenation (PSR) purposes. This device is safe and easy to use at beauty salons and homes. The effects of this device were investigated on the rat skins. Also, as a new method to improve PSR results, vitamin C ointment was combined with plasma. In this study, there were four groups of 5 Wistar rats. The first group received vitamin C ointment, the second received 5 min of high-voltage plasma, and the third and the fourth groups received 5 min of high- and low-voltage plasma and vitamin C ointment. This process was done every other day (3 sessions per week) for 6 weeks. To evaluate the thermal effect of plasma, the skin temperature was monitored. Also, the presence of reactive species was demonstrated by the use of optical spectroscopy. In addition, mechanical assays were performed to assess the effect of plasma and vitamin C on the tissue's mechanical strength. The mechanical assays showed a positive impact of plasma on the treated tissue compared to the control group. Also, changes in the collagen level and thickness of the epidermal layer were examined in histological studies. The results indicated an increase in collagen levels after using plasma alone and an accelerated skin reaction after using vitamin C combined with plasma therapy. The epidermal layer's thickness increased after applying high-voltage plasma, which indicates an increase in skin elasticity. This study demonstrates the positive effect of using the portable plasma device with vitamin C ointment on effective parameters in skin rejuvenation.

The Comparison of Biomechanical Volar and Dorsal Plating in Distal Part Radius Fractures; a Finite Element Analysis Study.

OBJECTIVE: To compare the stability of the radius stabilized fractured parts by volar and dorsal planting based on modeling approach. METHODS: Ten forearm models were created based on Computed Tomography (CT) Scan images by using of Mimics software. The distal part fracture of radius was induced in the models. The stress were developed and implanted in various parts of the bone and and their displacement were evaluated in volar and dorsal inserted implants. RESULTS: The results of this study showed that the stress developed in screws, implant and bony parts differed significantly between volar and dorsal plate conditions. The displacement of implant and bony parts in volar plating was more than dorsal plating (p=0.05). However, the screws displacement in dorsal plating significantly increased compared to volar plating. CONCLUSION: The stress developed in dorsal and volar implants is not too high to fail the structure. However, it seems that the irritation of soft tissue and tendon would be less in volar inserted implant than dorsal implant. It is recommended to use valor plating to be a good approach for stabilizing the distal part fracture of radius.

Determination of the correlation between muscle forces obtained from OpenSim and muscle activities obtained from electromyography in the elderly.

Measurement of muscle forces related to aging can help to better identify the gait impairment mechanisms in the elderly. To this end, musculoskeletal modeling has been developed to estimate muscle forces. This study aimed to check the validity of OpenSim modeling (i.e., computed muscle control) approach in elderly subjects. Kinematic and kinetic data and Electromyography (EMG) signals for four different muscles were collected in nine healthy elderly males during walking. Dynamic simulation was done within OpenSim. Correlation analysis was performed to quantitatively compare the maximum estimated muscle forces with maximum measured muscle activities during the first double limb support, single limb support, and the second double limb support phases. The area-time plots of OpenSim and EMG data during gait cycle were obtained for qualitative assessment. In quantitative assessment, a low to moderate correlation was observed for the peak of muscle force and muscle activation of four muscles during sub phases of gait. The muscle forces pattern from OpenSim was found to be relatively similar to the muscle activity pattern from EMG especially for Gastrocnemius Medialis. A low to moderate consistency between OpenSim and EMG in the elderly can be explained by using a single mathematical estimation approach.

Real diesel engine exhaust emission control: indirect non-thermal plasma and comparison to direct plasma for NOX, THC, CO, and CO2.

Recently, diesel engine exhaust emission control by non-thermal plasma (NTP) technology has been shown to be promising. However, carbon and soot deposition on the inner surface of the NTP reactor for direct plasma processing decreased the efficiency of the plasma process throughout the experiments. In the present work, the feasibility of indirect plasma processing was investigated as an innovative and novel method compared to direct plasma processing. Air was directed through an NTP at an applied voltage of VP-P = 7 kV and a flow rate of 1-4 L/min, and then, it was combined with engine exhaust gas at a flow rate of 5 L/min. In this case, the maximum conversion of NOX was 64.9% at 4 L/min. However, for direct plasma processing at 5 L/min, NO conversion was 58%, which proves that the indirect NTP process can decrease NOX concentration effectively. The maximum conversion for unburned hydrocarbon (UHC), carbon monoxide (CO) and carbon dioxide (CO2) was obtained as 2%, 4% and 0.7% at 4, 2 and 3 L/min in indirect plasma processing; While their remove rate for direct plasma processing was 16.3%, -0.5% and 13.2%, respectively.

Cold low pressure O2 plasma treatment of Crocus sativus: An efficient way to eliminate toxicogenic fungi with minor effect on molecular and cellular properties of saffron.

In this study cold low pressure radiofrequency oxygen plasma was used for the first time to inactivate toxicogenic fungi proliferation on saffron. Varieties of plasma produced reactive oxygen species which were investigated by optical emission spectroscopy. The data were indicative of the absence of UV radiation. Effects of plasma treatment on antioxidant activity, metabolic content, colour, odour and flavour parameters and physical impact on saffron were investigated. A range of plasma powers and exposure times were assayed in suppression of fungal growth. Amongst which power of 60 W for 15 min was used to eradicate Aspergillus and other microorganisms. The ferric reducing antioxidant power was changed from 1778.21 to 1674.25 mM/g dry weight following plasma treatment. Moreover, crocin ester, picrocrocin and safranal metabolites reduced insignificantly. Additionally, plasma had no significant impact on colour, odour and flavour of saffron.

Study on Physio-chemical Properties of plasma polymerization in C2H2/N2 plasma and Their Impact on COL X.

Nitrogen-containing plasma polymerization is of considerable interest for tissue engineering due to their properties on cell adhesion and mesenchymal stem cells (MSCs) response. In this study, low-pressure RF plasma of acetylene and nitrogen was used to deposit nitrogen-containing plasma polymerized coatings on several substrates. Deposition kinetics and surface characteristics of coatings were investigated in terms of RF power and gas flow ratio. OES was used to monitor the plasma process and investigate the relation between the film structure and plasma species. Presence of several bonds and low concentration of amine functional groups were determined using FTIR and Colorimetric methods. Contact angle goniometry results indicated about 30% increase in surface hydrophilicity. Stability of coatings in air and two different liquid environments was examined by repeating surface free energy measurements. Deposited films exhibited acceptable stability during the storage duration. Surface roughness measured by AFM was found to decrease with growing concentration of nitrogen. The deposition rate increased with increasing RF power and decreased with growing concentration of nitrogen. Zeta potential measurements of coatings revealed the negative potential on the surface of the thin films. Temporary suppression of collagen X in the presence of plasma coatings was confirmed by RT-PCR results.