After contusion-derived spinal cord injury, (SCI) there is localized tissue disruption and energy failure that results in early necrosis and delayed apoptosis, events that contribute to chronic central pain in a majority of patients. We assessed the extent of contusion-induced apoptosis of neurons in a known central pain-signaling pathway, the spinothalamic tract (STT), which may be a contributor to SCI-induced pain. We observed the loss of STT cells and localized increase of DNA fragmentation and cytoplasmic histone-DNA complexes, which suggested potential apoptotic changes among STT neurons after SCI. We also showed SCI-associated changes in the expression of the antiapoptotic protein Bcl-xL, especially among STT cells, consistent with the hypothesis that Bcl-xL regulates the extent of apoptosis after SCI. Apoptosis in the injured spinal cord correlated well with prompt decreases in Bcl-xL protein levels and Bcl-xL/Bax protein ratios at the contusion site. We interpret these results as evidence that regulation of Bcl-xL may play a role in neural sparing after spinal injury and pain-signaling function.

Background Repetitive transcranial magnetic stimulation (rTMS) is acknowledged to be crucial to manage freezing of gait (FOG) and cognitive impairment for patients with Parkinson's disease (PD), but its effectiveness is unclear. Objective To determine the effects of rTMS on FOG and cognitive function in people with PD and to investigate potential factors that modulate the rTMS effects. Methods Databases searched included PubMed, Web of Science, EMBASE, and the Cochrane Library from inception to December 31, 2021. Eligible studies include a controlled randomized clinical trial of rTMS intervention for FOG and cognitive dysfunction in PD patients. The weighted mean difference (WMD) with 95% confidence intervals (CI) were calculated with fixed‐effects models. The outcome of the study included gait and cognitive assessments. Results Sixteen studies with a total of 419 patients were included. Fixed‐effects analysis revealed that rTMS was effective in improving freezing of gait questionnaire scores (short‐term effect: WMD = −0.925, 95% CI: −1.642 to −0.209, p = .011; long‐term effect: WMD = −2.120, 95% CI: −2.751 to −1.489, p = .000), 10‐m walking time (short‐term effect: WMD = −0.456, 95% CI: −0.793 to −0.119, p = .008; long‐term effect: WMD = −0.526, 95% CI: −0.885 to −0.167, p = .004), Timed Up‐and‐Go scores (short‐term effect: WMD = −1.064, 95% CI: −1.555 to −0.572, p = .000; long‐term effect: WMD = −1.097, 95% CI: −1.422 to −0.772, p = .000), Montreal cognitive assessment (WMD = 3.714, 95% CI: 2.567 to 4.861, p = .000), and frontal assessment battery (WMD = −0.584, 95% CI: −0.934 to −0.234, p = .001). Conclusions RTMS showed a beneficial effect on FOG and cognitive dysfunction in parkinsonism. However, the optimal rTMS protocol has not been determined and further high‐quality studies are needed.

Hexagonal boron nitride/silicon carbide (h-BN/SiC) ceramics were fabricated by a spark plasma sintering (SPS) method. Phase and microstructure of ceramics were characterized and observed, respectively, using the X-ray diffraction, scanning electron microscope and electron probe microanalysis. The effect of molar ratios of SiC to h-BN on the microstructure, relative density, hardness, thermal conductivity, and the heating rate by microwaves on the ceramics were investigated. The results showed that the orientation of flake-like h-BN was significantly influenced by SiC content in h-BN/SiC ceramics. With the increasing of SiC content, the h-BN flakes gradually became an isotropic distribution from the preferred orientation aligning in a SPS pressure direction. The relative density of h-BN/SiC ceramics was 97.6 ± 0.9% at a molar ratio of SiC to h-BN of 40/60 mol%. The preferential orientation of h-BN flakes contributed to a relatively high thermal conductivity along the SPS pressure direction, which was beneficial to increasing the heating rate of h-BN/SiC ceramics in microwave fields.

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