ObjectiveTo investigate the neuroprotective effect of glycosides of cistanches （GCs） in 1-methyl-4-phenyl-1，2，3，6-tetrahydropyridine （MPTP）-induced Parkinson’s disease （PD） model mice and its potential mechanism. MethodsForty mice were randomly divided into control group， PD group， GCs group and levodopa （L-DOPA） group， with 10 mice in each group. The control group received intraperitoneal injection of normal saline， while the other groups were intraperitoneally injected with MPTP （30 mg/kg） once daily for 5 consecutive days. After model establishment， the control group and PD group were intragastrically administered normal saline， and the GCs group and L-DOPA group received intragastric administration once daily for 28 consecutive days， at doses of 100 mg/kg and 50 mg/kg， respectively. The open field test and rotarod test were used to evaluate motor function. Immunohistochemistry was performed to detect the number of tyrosine hydroxylase （TH）-positive neurons in the substantia nigra of the midbrain. Transmission electron microscopy was adopted to observe the ultrastructure of mitochondria in the substantia nigra. Biochemical assays were used to determine the levels of glutathione （GSH）， malondialdehyde （MDA）， total superoxide dismutase （T-SOD） and reactive oxygen species （ROS） in substantia nigra tissues. Western blot was applied to detect the protein expression of TH， nuclear factor erythroid 2-related factor 2 （Nrf2）， Kelch-like ECH-associated protein 1 （Keap-1） and heme oxygenase-1 （HO-1） in substantia nigra tissues. ResultsCompared with the control group， mice in the PD group exhibited markedly impaired motor function， significantly decreased T-SOD activity， obvious reductions in the number of TH-positive neurons and GSH content， as well as elevated MDA and ROS levels in the substantia nigra （P<0.01）. Compared with the PD group， mice in the GCs group showed improved motor function， increased T-SOD activity， higher number of TH-positive neurons and elevated GSH content， accompanied by decreased MDA and ROS levels （P<0.05）. In the control group， mitochondria in the substantia nigra displayed normal morphology without obvious blurred membrane structures or vacuolar degeneration. The PD group presented mitochondrial swelling， disordered cristae and vacuolar changes， whereas these mitochondrial pathological alterations were alleviated in the GCs group. Compared with the control group， the protein levels of TH， Nrf2 and HO-1 were significantly downregulated， while Keap-1 protein expression was markedly upregulated in the PD group （P<0.01）. Compared with the PD group， the GCs group showed significant upregulation of TH， Nrf2 and HO-1 protein levels and a notable reduction in Keap-1 protein level （P<0.05）. ConclusionGCs ameliorate motor dysfunction and attenuate dopaminergic neuronal and mitochondrial damage in MPTP-induced PD model mice. These effects may be associated with modulation of Nrf2/HO-1 pathway-related protein expression， enhancement of antioxidant capacity， and alleviation of oxidative stress.

Objective:To explore effect of human umbilical cord mesenchymal stem cells(hUC-MSCs)on macrophage M1/M2 polarization.Methods:hUC-MSCs were co-cultured with pTHP-1 cells which were macrophage-like cells induced by PMA and tran-scriptome sequencing data were analyzed.Differentially expressed genes were screened and analyzed by GO and KEGG enrichment analysis.Effect of hUC-MSCs on pTHP-1 cells proliferation was analyzed by cell proliferation assay(CCK-8 and EdU).Flow cytometry was used to verify influence of hUC-MSCs on relative contents of inflammatory cytokine TNF-α and anti-inflammatory cytokine IL-10 in pTHP-1 cells which were interaction with LPS.Effect of hUC-MSCs on M1/M2-related molecular phenotype of pTHP-1 cells was studied by qRT-PCR and flow cytometry.Results:Transcriptome sequencing data analysis showed that M1-related genes TNF-α(P<0.05)and HLA-DRA(P<0.01)decreased to a great extent and M2-related gene ARG1(P<0.05)increased to a great extent in pTHP-1 cells after co-culture with hUC-MSCs,suggesting that hUC-MSCs inhibited macrophage M1 polarization.GO and KEGG analysis showed that these dysregulated genes regulated inflammation and immune response.hUC-MSCs inhibited proliferation of pTHP-1 cells,reduced content of TNF-α and increased content of IL-10(P<0.001).qRT-PCR and flow cytometry showed mRNA expressions of HLA-DRA(P<0.05)and CD68(P<0.01)and CD14+CD11c+M1 macrophage percentage were down-regulated,while mRNA expressions of CD163(P<0.001),CD206(P<0.001)and CD14+CD163+M2 macrophage percentage were significantly up-regulated in pTHP-1 cells after co-culture with hUC-MSCs.Conclusion:hUC-MSCs inhibit macrophage polarization to M1 and promote polariza-tion to M2 in vitro.

Three-dimensional tooth segmentation is the segmentation of single-tooth models from a digital dental model. It is an important foundation for diagnosis, planning, treatment and customized appliance manufacturing in digital orthodontics. With the deep integration of artificial intelligence technology and big data from stomatology, the use of deep learning algorithms to assist 3D tooth segmentation has gradually become mainstream. This review summarizes the current situation of deep learning algorithms that assist 3D tooth segmentation from the aspects of dataset establishment, algorithm architecture, algorithm performance, innovation and advantages, deficiencies of current research and prospects. The results of the literature review showed that deep learning tooth segmentation methods could obtain an accuracy of more than 95% and had good robustness. However, the segmentation of complex dental models, operation time and richness of the training database still need to be improved. Research and development of the "consumption reduction and strong core" algorithm, establishment of an authoritative data sample base with multiple centers, and expansion of data application depth and breadth will lead to further development in this field.

Objective:To investigate the efficacy and safety of intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) in patients with maintenance hemodialysis (MHD) and acute ischemic stroke.Methods:The clinical data of 235 patients with acute ischemic stroke receiving MHD were collected in our hospital from March 2018 to October 2021. According to the treatment methods chosen by themselves, these patients were divided into control group ( n=70, only receiving standardized secondary stroke prevention), rt-PA low-dose group ( n=85, receiving rt-PA intravenous thrombolysis, 0.6 mg/kg) and rt-PA standard-dose group ( n=80, receiving rt-PA intravenous thrombolysis, 0.9 mg/kg). The effective rate 24 h after treatment, good efficacy rate 7 d after treatment, and good prognosis rate and mortality 90 d after treatment were used to evaluate the effectiveness. The incidences of intracranial hemorrhage, symptomatic intracranial hemorrhage, and severe extracranial hemorrhage 90 d after treatment were used to evaluate the safety. Results:There was no statistical difference in the good prognosis rate 90 d after treatment among the rt-PA low-dose group, the rt-PA standard-dose group and the control group (71.8%, 68.8%, and 64.3%; P>0.05), but the effective rate 24 h after treatment and good efficacy rate 7 d after treatment in the rt-PA low-dose group and rt-PA standard-dose group (44.7%, 57.7%; 46.3%, 62.5%) were both significantly higher than those in the control group (27.1%, 38.6%; P<0.05). The mortality 90 d after treatment in the rt-PA low-dose group (7.1%) was significantly lower than that in the rt-PA standard-dose group (22.5%) and control group (21.4%, P<0.05). The incidences of intracranial hemorrhage and symptomatic intracranial hemorrhage in the rt-PA low-dose group (8.2%, 3.5%) were significantly lower than those in the rt-PA standard-dose group (22.5%, 16.3%; P<0.05), and the incidences of extracranial complications and gastrointestinal bleeding (5.9%, 1.2%) were significantly lower than those in the rt-PA standard-dose group (18.8%, 10.0%; P<0.05). Conclusion:Intravenous thrombolytic therapy with 0.6 mg/kg rt-PA is recommended for acute ischemic stroke patients receiving MHD.

Endogenously eliminating the hematoma is a favorable strategy in addressing intracerebral hemorrhage (ICH). This study sought to determine the role of retinoid X receptor-α (RXR-α) in the context of hematoma absorption after ICH. Our results showed that pharmacologically activating RXR-α with bexarotene significantly accelerated hematoma clearance and alleviated neurological dysfunction after ICH. RXR-α was expressed in microglia/macrophages, neurons, and astrocytes. Mechanistically, bexarotene promoted the nuclear translocation of RXR-α and PPAR-γ, as well as reducing neuroinflammation by modulating microglia/macrophage reprograming from the M1 into the M2 phenotype. Furthermore, all the beneficial effects of RXR-α in ICH were reversed by the PPAR-γ inhibitor GW9662. In conclusion, the pharmacological activation of RXR-α confers robust neuroprotection against ICH by accelerating hematoma clearance and repolarizing microglia/macrophages towards the M2 phenotype through PPAR-γ-related mechanisms. Our data support the notion that RXR-α might be a promising therapeutic target for ICH.
Anilides/pharmacology* ; Cerebral Hemorrhage/drug therapy* ; Hematoma/drug therapy* ; Humans ; Macrophages ; Microglia ; Neuroprotection ; PPAR gamma ; Retinoid X Receptor alpha

Objective:To document any improvement in the breathing control of stroke survivors with dysarthria after practicing Liuzijue qigong.Methods:A total of 157 stroke survivors with dysarthria and abnormal respiration control were randomly divided into an observation group and a control group. Both groups were given traditional breathing training and basic articulation training (including articulatory organ training and speech training). The observation group also received training in Liuzijue qigong. It requires inhaling through the nose and exhaling through the mouth while producing the speech sounds xu, he, hu, si, chui and xi. The training lasted two weeks. Both groups were then evaluated using the modified Frenchay dysarthria assessment. Maximum phonation time, maximum counting ability and volume were also recorded as secondary indexes.Results:After the 2-week intervention, significant improvement was observed in the average scores on all of the indexes, with all of the observation group′s average scores except for volume significantly better than those of the control group. The average volume scores were significantly improved, but not significantly different.Conclusion:Supplementing basic articulation training with Liuzijue qigong can improve respiratory function and the speaking ability of stroke survivors with dysarthria. It is worthy of wider clinical application.

Endogenously eliminating the hematoma is a favorable strategy in addressing intracerebral hemorrhage (ICH). This study sought to determine the role of retinoid X receptor-α (RXR-α) in the context of hematoma absorption after ICH. Our results showed that pharmacologically activating RXR-α with bexarotene significantly accelerated hematoma clearance and alleviated neurological dysfunction after ICH. RXR-α was expressed in microglia/macrophages, neurons, and astrocytes. Mechanistically, bexarotene promoted the nuclear translocation of RXR-α and PPAR-γ, as well as reducing neuroinflammation by modulating microglia/macrophage reprograming from the M1 into the M2 phenotype. Furthermore, all the beneficial effects of RXR-α in ICH were reversed by the PPAR-γ inhibitor GW9662. In conclusion, the pharmacological activation of RXR-α confers robust neuroprotection against ICH by accelerating hematoma clearance and repolarizing microglia/macrophages towards the M2 phenotype through PPAR-γ-related mechanisms. Our data support the notion that RXR-α might be a promising therapeutic target for ICH.

In the original publication Fig. 1D and supplementary material is incorrect. The correct figure and supplementary material is provided in this correction.

One major strategy to generate genetically modified mouse models is gene targeting in mouse embryonic stem (ES) cells, which is used to produce gene-targeted mice for wide applications in biomedicine. However, a major bottleneck in this approach is that the robustness of germline transmission of gene-targeted ES cells can be significantly reduced by their genetic and epigenetic instability after long-term culturing, which impairs the efficiency and robustness of mouse model generation. Recently, we have established a new type of pluripotent cells termed extended pluripotent stem (EPS) cells, which have superior developmental potency and robust germline competence compared to conventional mouse ES cells. In this study, we demonstrate that mouse EPS cells well maintain developmental potency and genetic stability after long-term passage. Based on gene targeting in mouse EPS cells, we established a new approach to directly and rapidly generate gene-targeted mouse models through tetraploid complementation, which could be accomplished in approximately 2 months. Importantly, using this approach, we successfully constructed mouse models in which the human interleukin 3 (IL3) or interleukin 6 (IL6) gene was knocked into its corresponding locus in the mouse genome. Our study demonstrates the feasibility of using mouse EPS cells to rapidly generate mouse models by gene targeting, which have great application potential in biomedical research.

Recently we have established a new culture condition enabling the derivation of extended pluripotent stem (EPS) cells, which, compared to conventional pluripotent stem cells, possess superior developmental potential and germline competence. However, it remains unclear whether this condition permits derivation of EPS cells from mouse strains that are refractory or non-permissive to pluripotent cell establishment. Here, we show that EPS cells can be robustly generated from non-permissive NOD-scid Il2rg mice through de novo derivation from blastocysts. Furthermore, these cells can also be efficiently generated by chemical reprogramming from embryonic NOD-scid Il2rg fibroblasts. NOD-scid Il2rg EPS cells can be expanded for more than 20 passages with genomic stability and can be genetically modified through gene targeting. Notably, these cells contribute to both embryonic and extraembryonic lineages in vivo. More importantly, they can produce chimeras and integrate into the E13.5 genital ridge. Our study demonstrates the feasibility of generating EPS cells from refractory mouse strains, which could potentially be a general strategy for deriving mouse pluripotent cells. The generation of NOD-scid Il2rg EPS cell lines permits sophisticated genetic modification in NOD-scid Il2rg mice, which may greatly advance the optimization of humanized mouse models for biomedical applications.