Polydatin Protects Bone Marrow Stem Cells against Oxidative Injury: Involvement of Nrf 2/ARE Pathways

Polydatin, a glucoside of resveratrol, has been reported to possess potent antioxidative effects. In the present study, we aimed to investigate the effects of polydatin in bone marrow-derived mesenchymal stem cells (BMSCs) death caused by hydrogen peroxide (H2O2), imitating the microenvironment surrounding transplanted cells in the injured spinal cord in vitro. In our study, MTT results showed that polydatin effectively prevented the decrease of cell viability caused by H2O2. Hochest 33258, Annexin V-PI, and Western blot assay showed H2O2-induced apoptosis in BMSCs, which was attenuated by polydatin. Further studies indicated that polydatin significantly protects BMSCs against apoptosis due to its antioxidative effects and the regulation of Nrf 2/ARE pathway. Taken together, our results indicate that polydatin could be used in combination with BMSCs for the treatment of spinal cord injury by improving the cell survival and oxidative stress microenvironments

Significant differences in knee kinematics of healthy subjects with high and low anterior tibial laxity

BackgroundAnterior tibial laxity is considered to be a risk factor for knee injuries, including anterior cruciate ligament ruptures. The anterior cruciate ligament reconstruction also aims to restore anterior tibial laxity. While anterior tibial laxity is considered to be linked to dynamic knee stability, the mechanisms connecting anterior tibial laxity to these stability issues are not fully understood. The purpose of this study was to investigate the kinematic alterations between different anterior tibial laxity in healthy subjects. We hypothesized that anterior tibial laxity affects the anteroposterior tibial displacement during dynamic movements.MethodsThis study involved thirty-five healthy subjects. There were twenty males and fifteen females with an average age of 18.91 ± 0.78 years. Their knees were categorized into “Tight” (the smallest 50%) and “Lax” (the largest 50%) groups based on anterior tibial laxity measurements using a Kneelax3 arthrometer. Kinematic data were collected using a three-dimensional motion capture system when they performed level walking, upslope walking, and vertical jumping. The knee kinematics were recorded for statistical analysis. We used independent sample t-tests to analyze key kinematic differences between groups.ResultsThe “Lax” group exhibited increased posterior tibial translation during upslope walking (5.4 ± 2.22 mm at swing max flexion, p = 0.018) and vertical jumping (8.5 ± 2.78 mm at propulsion max flexion, p = 0.003; 7.6 ± 3.17 mm at landing max flexion, p = 0.019) than the “Tight” group. Significant differences in tibial internal rotation were observed during initial contact of the gait cycle of level walking (1.9° ± 0.95°, p = 0.049) and upslope walking (2.1° ± 1.03°, p = 0.041) in the “Lax” group compared to the “Tight” group. No significant differences in adduction/abduction or medial/lateral tibial translation were found between groups.ConclusionThe study revealed that high anterior tibial laxity resulted in increased posterior tibial translation and tibial internal rotation. High anterior tibial laxity resulted in dynamic instability of knees during motions, especially in high-demanding activities like upslope or vertical jumping. However, further research is needed to explore the clinical functional effects of knee laxity

Polydatin Protects Bone Marrow Stem Cells against Oxidative Injury: Involvement of Nrf 2/ARE Pathways

Polydatin, a glucoside of resveratrol, has been reported to possess potent antioxidative effects. In the present study, we aimed to investigate the effects of polydatin in bone marrow-derived mesenchymal stem cells (BMSCs) death caused by hydrogen peroxide (H2O2), imitating the microenvironment surrounding transplanted cells in the injured spinal cord in vitro. In our study, MTT results showed that polydatin effectively prevented the decrease of cell viability caused by H2O2. Hochest 33258, Annexin V-PI, and Western blot assay showed H2O2-induced apoptosis in BMSCs, which was attenuated by polydatin. Further studies indicated that polydatin significantly protects BMSCs against apoptosis due to its antioxidative effects and the regulation of Nrf 2/ARE pathway. Taken together, our results indicate that polydatin could be used in combination with BMSCs for the treatment of spinal cord injury by improving the cell survival and oxidative stress microenvironments

Median nerve compression caused by superficial brachial artery: an unusual clinical case

An iatrogenic pseudoaneurysm of the radial artery and spontaneous venous malformation are associated with median nerve compression. However, the superficial brachial artery (SBA) has rarely been described as the cause of neurological deficits due to median nerve compression. A 61-year-old man was admitted to our clinic with a 1-year history of intermittent aching palsy in the left thumb that had progressed to the first three fingers. Clinical examination revealed mild sensory disturbance and hyperpathia in the first three fingers and weakness of the opponens pollicis. Ultrasound and magnetic resonance imaging confirmed that the SBA was compressing the median nerve by almost one-third. When anomalies of the SBA impinge on the median nerve, pulsatile pressure is applied to the nerve trunk. This may trigger ectopic stimulation of sensory fibers, leading to severe pain, sensory neuropathy, and motor disturbance. Considering the substantial difficulties and risks of a surgical operation as well as the patient’s wish to undergo conservative treatment, we performed muscle relaxation and acupuncture to relieve the pressure of the surrounding soft tissue and in turn decrease the impingement of the SBA on the median nerve. A satisfactory treatment effect was reached in this case. </jats:p

Disappearance of dimits shift in realistic fusion reactor plasmas with negative magnetic shear

This study employs gyrokinetic simulations to investigate ion temperature gradient (ITG) turbulence in realistic fusion reactor plasmas featuring reversed magnetic shear. The weakly negative magnetic shear is observed to be more stable for the ITG instability than strongly positive shear in this equilibrium configuration, primarily stemming from the scarcity of mode rational surfaces induced by the weak negative shear. This superiority in suppression for the negative shear persists in nonlinear turbulence with zonal flow artificially eliminated, where the emergence of turbulence solitons is observed and found associated with locally dense mode rational surfaces. However, the difference in transport levels among different magnetic shears diminishes in the presence of self-consistently generated zonal flow, accompanied by the disappearance of turbulence solitons. The nonlinear generation of zonal flow is found to be significantly affected by the magnetic shear. The study reveals a remarkable phenomenon that the Dimits shift no longer exists for negative magnetic shear, which is attributed to the weakness of the zonal flow generation near the ITG marginal stability