Very high-frequency, gate-tunable CrPS4 nanomechanical resonator with single mode.

Two-dimensional (2D) antiferromagnetic semiconductor chromium thiophosphate (CrPS4) has gradually become a major candidate material for low-dimensional nanoelectromechanical devices due to its remarkable structural, photoelectric characteristics and potentially magnetic properties. Here, we report the experimental study of a new few-layer CrPS4 nanomechanical resonator demonstrating excellent vibration characteristics through the laser interferometry system, including the uniqueness of resonant mode, the ability to work at the very high frequency, and gate tuning. In addition, we demonstrate that the magnetic phase transition of CrPS4 strips can be effectively detected by temperature-regulated resonant frequencies, which proves the coupling between magnetic phase and mechanical vibration. We believe that our findings will promote the further research and applications of the resonator for 2D magnetic materials in the field of optical/mechanical signal sensing and precision measurement.

Neuron-Derived Exosomes Promote the Recovery of Spinal Cord Injury by Modulating Nerve Cells in the Cellular Microenvironment of the Lesion Area.

During spinal cord injury (SCI), the homeostasis of the cellular microenvironment in the injured area is seriously disrupted, which makes it extremely difficult for injured neurons with regenerative ability to repair, emphasizing the importance of restoring the cellular microenvironment at the injury site. Neurons interact closely with other nerve cells in the central nervous system (CNS) and regulate these cells. However, the specific mechanisms by which neurons modulate the cellular microenvironment remain unclear. Exosomes were isolated from the primary neurons, and their effects on astrocytes, microglia, oligodendrocyte progenitor cells (OPCs), neurons, and neural stem cells were investigated by quantifying the expression of related proteins and mRNA. A mouse SCI model was established, and neuron-derived exosomes were injected into the mice by the caudal vein to observe the recovery of motor function in mice and the changes in the nerve cells in the lesion area. Neuron-derived exosomes could reverse the activation of microglia and astrocytes and promote the maturation of OPCs in vivo and in vitro. In addition, neuron-derived exosomes promoted neurite outgrowth of neurons and the differentiation of neural stem cells into neurons. Moreover, our experiments showed that neuron-derived exosomes enhanced motor function recovery and nerve regeneration in mice with SCI. Our findings highlight that neuron-derived exosomes could promote the repair of the injured spinal cord by regulating the cellular microenvironment of neurons and could be a promising treatment for spinal cord injury.

Formononetin improves the inflammatory response and bone destruction in knee joint lesions by regulating the NF-kB and MAPK signaling pathways.

Formononetin (FMN) is a phytoestrogen that belongs to the isoflavone family. It has antioxidant and anti-inflammatory effects, as well as, many other biological activities. Existing evidence has aroused interest in its ability to protect against osteoarthritis (OA) and promote bone remodeling. To date, research on this topic has not been thorough and many issues remain controversial. Therefore, the purpose of our study was to explore the protective effect of FMN against knee injury and clarify the possible molecular mechanisms. We found that FMN inhibited osteoclast formation induced by receptor activator of NF-κB ligand (RANKL). Inhibition of the phosphorylation and nuclear translocation of p65 in the NF-κB signaling pathway plays a role in this effect. Similarly, during the inflammatory response of primary knee cartilage cells activated by IL-1ß, FMN inhibited the NF-κB signaling pathway and the phosphorylation of the ERK and JNK proteins in the MAPK signaling pathway to suppress the inflammatory response. In addition, in vivo experiments showed that both low- and high-dose FMN had a clear protective effect against knee injury in the DMM (destabilization of the medial meniscus) model, and the therapeutic effect of high-dose FMN was stronger. In conclusion, these studies provide evidence of the protective effect of FMN against knee injury.

Application of hepatitis B immunoglobulin in prevention of mother-to-child transmission of chronic hepatitis B in HBsAg- and HBeAg-positive mother.

The aim of our study was to compare the efficacy of two dosages of hepatitis B immunoglobulin (HBIG) combined with HBV vaccine (HBVac) to prevent mother-to-child transmission (MTCT) of hepatitis B in HBsAg- and HBeAg-positive mother. We enrolled 331 mother-infant pairs with HBsAg- and HBeAg-positive maternal state from the Women's Hospital School of Medicine of Zhejiang University. Newborns were randomly distributed into two groups according to the dosages of HBIG injection: 100 IU and 200 IU. Newborns from both groups were injected with HBVac in the same doses. We compared the immune outcomes between the two groups and explore the influencing factors of immune outcomes through regression analysis. There was no statistically significant relationship between HBsAg serological transmission of newborns and dosages of HBIG in HBsAg- and HBeAg-positive mother (p > .05). The Logistic regression showed that high DNA load is a risk factor for passive-active immunoprophylaxis failure for both 100 IU and 200 IU group, but higher-dosage HBIG is not necessary for higher-viral-load pregnant women with HBsAg- and HBeAg-positive. In conclusion, combined application of HBVac and a single dose of 100 IU HBIG can achieve the ideal MTCT interruption results for HBsAg- and HBeAg-positive pregnant women.IMPACT STATEMENTWhat is already known on this subject? Passive-active immunoprophylaxis is proved to be effective in preventing mother-to-child transmission of hepatitis B. Hepatitis B vaccine combined with 100 IU or 200 IU immunoglobulin is mostly recommended in China.What do the results of this study add? At present, there is still a lack scientific basis for improving existing strategies and measures to prevent mother-to-child transmission of hepatitis B in China.What are the implications of these findings for clinical practice and/or further research? 100 IU and 200 IU immunoglobulin show equivalent blocking effect, and combined use of hepatitis B vaccine and 100 IU immunoglobulin is more cost-effective.