Objective:To explore the molecular mechanism by which the methionine adenosyltransferase 2A (MAT2A)/β-catenin/zinc finger E-box binding homeobox 1 (ZEB1)/epithelial-mesenchymal transition (EMT) pathway regulates neural tube defect (NTD) through intracellular S-adenosylmethionine (SAM).Methods:A mouse NTD model was induced using the SAM metabolic disorder inhibitor ethionine. Eighty specific pathogen-free C57BL/6 mice were divided into three groups: a normal group (36 mice), an ethionine group (46 mice), and an ethionine+SAM group (44 mice). Phosphate-buffered saline (PBS), ethionine, and ethionine+SAM were respectively injected intraperitoneally on embryonic day 7.5 (E7.5), and the mice were sacrificed on E10.5. Embryonic tissues were collected, and the morphology of embryos in each group was observed under a stereomicroscope. The interaction between ethionine and MAT2A was analyzed using Autodock software. The expression levels of MAT2A, β-catenin, ZEB1, and EMT-related proteins in the brain tissues of embryos from the three groups were measured using immunofluorescence, immunohistochemistry, Western blotting, enzyme-linked immunosorbent assay (ELISA), and real-time quantitative polymerase chain reaction (RT-qPCR). Variance analysis was used for intergroup comparisons.Results:(1) Autodock analysis results showed that MAT2A binds to ethionine through covalent bonds, exhibiting a complementary effect, thereby accelerating the expression of MAT2A. (2) After successful construction of the NTD model, normal embryos were plump with well-developed brains. NTD embryos showed delayed development, obvious anencephaly, unclosed neural tubes, and asymmetry. (3) The levels of SAM and SAH in the embryonic tissues of the ethionine group were significantly lower than those in the normal group (1 737.56±95.64 vs. 872.33±205.11, and 89.17±9.50 vs. 51.25±9.48, respectively). The SAM and SAH levels in the ethionine+SAM group was 1 197.00±222.27 and 66.61±12.25, significantly higher than those in the ethionine group ( P<0.017). Compared with the normal group and the ethionine+SAM group, the expression of MAT2A mRNA in the embryonic brain tissue of the ethionine group was significantly upregulated (1.00±0.00, 1.59±0.52, and 2.42±0.53, respectively, F=49.64, P<0.001; pairwise comparisons between groups P<0.017). (4) Compared with the normal group, the expression of Ctnnb1 in the ethionine group was reduced, and the expression of Ctnnb1 in the ethionine+SAM group was higher than that in the ethionine group (1.00±0.00, 0.38±0.16, and 0.76±0.10, respectively, F=149.03, P<0.001; pairwise comparisons between groups P<0.017). (5) The expression of ZEB1 in the ethionine group was higher than that in the normal group and the ethionine+SAM group (2.91±0.55, 1.00±0.00, and 1.61±0.20, respectively, F=150.01, P<0.001; pairwise comparisons between groups P<0.017). (6) The expression levels of E-cadherin and Vimentin in the ethionine group were lower than those in the normal group. In contrast, the expression of N-cadherin was higher than that in the normal group. After SAM supplementation, the expression levels of E-cadherin and Vimentin were upregulated, and the expression level of N-cadherin was downregulated (0.54±0.12, 1.00±0.00, and 0.72±0.14, respectively, F=87.44; 0.53±0.17, 1.00±0.00, and 0.76±0.09, F=87.44; 3.11±0.53, 1.00±0.00, and 2.13±0.56, F=95.54; all P<0.001; pairwise comparisons within the same index group P<0.017]). Conclusions:Ethionine promotes the expression of MAT2A, leading to reduced SAM production. Ethionine regulates the level of ZEB1 by increasing MAT2A and inhibits the EMT process to interfere with methionine cycle metabolism, ultimately resulting in NTD.

Objective:To evaluate the impact of oral melatonin on clinical pregnancy outcomes in elderly infer-tile patients with diminished ovarian reserve(DOR)after in vitro fertilization and embryo transfer(IVF-ET).Methods:Sixty-two elderly infertile patients with DOR who underwent IVF at the Reproductive Medicine Center of Qinghai Province People's Hospital from January 1,2022 to June 30,2023 were selected.They were divided into intervention group(24 cases)and control group(38 cases)according to whether they received oral melatonin pretreatment before ovulation induction.Follicular fluid without diluent or blood contamination was collected from the first large follicle on the day of oocyte retrieval,and melatonin levels and 8-hydroxy-2'-deoxyglycoside(8-OHdG)levels in the follicular gluid were measured.Ovulation promotion indicators and pregnancy outcomes were compared and analyzed between the two groups.Results:The concentration of melatonin in follicular fluid in the intervention group was significantly higher than that in the control group(31.75 ng/L vs.10.40 ng/L,P＜0.001),the concentration of 8-OHdG was lower than that of the control group(133.61 ng/L vs.145.30 ng/L,P=0.004);the implantation rate in the intervention group was significantly higher than that in the control group(56.10％vs.26.87％,P=0.002),and the biochemical pregnancy rate in the intervention group was significantly higher than that in the control group(12.50％vs.0,P=0.050).There were no significant differences in normal fertilization rate,high-quality embryo rate,clinical pregnancy rate and cumulative live birth rate between the two groups(P＞0.05).Conclusions:Oral melatonin can increase its level in follicular fluid,which is beneficial in improving endom-etrial receptivity,and has a certain positive effect on improving IVF-ET outcomes.

Objective:To evaluate the impact of oral melatonin on clinical pregnancy outcomes in elderly infer-tile patients with diminished ovarian reserve(DOR)after in vitro fertilization and embryo transfer(IVF-ET).Methods:Sixty-two elderly infertile patients with DOR who underwent IVF at the Reproductive Medicine Center of Qinghai Province People's Hospital from January 1,2022 to June 30,2023 were selected.They were divided into intervention group(24 cases)and control group(38 cases)according to whether they received oral melatonin pretreatment before ovulation induction.Follicular fluid without diluent or blood contamination was collected from the first large follicle on the day of oocyte retrieval,and melatonin levels and 8-hydroxy-2'-deoxyglycoside(8-OHdG)levels in the follicular gluid were measured.Ovulation promotion indicators and pregnancy outcomes were compared and analyzed between the two groups.Results:The concentration of melatonin in follicular fluid in the intervention group was significantly higher than that in the control group(31.75 ng/L vs.10.40 ng/L,P＜0.001),the concentration of 8-OHdG was lower than that of the control group(133.61 ng/L vs.145.30 ng/L,P=0.004);the implantation rate in the intervention group was significantly higher than that in the control group(56.10％vs.26.87％,P=0.002),and the biochemical pregnancy rate in the intervention group was significantly higher than that in the control group(12.50％vs.0,P=0.050).There were no significant differences in normal fertilization rate,high-quality embryo rate,clinical pregnancy rate and cumulative live birth rate between the two groups(P＞0.05).Conclusions:Oral melatonin can increase its level in follicular fluid,which is beneficial in improving endom-etrial receptivity,and has a certain positive effect on improving IVF-ET outcomes.

Objective:To explore the molecular mechanism by which the methionine adenosyltransferase 2A (MAT2A)/β-catenin/zinc finger E-box binding homeobox 1 (ZEB1)/epithelial-mesenchymal transition (EMT) pathway regulates neural tube defect (NTD) through intracellular S-adenosylmethionine (SAM).Methods:A mouse NTD model was induced using the SAM metabolic disorder inhibitor ethionine. Eighty specific pathogen-free C57BL/6 mice were divided into three groups: a normal group (36 mice), an ethionine group (46 mice), and an ethionine+SAM group (44 mice). Phosphate-buffered saline (PBS), ethionine, and ethionine+SAM were respectively injected intraperitoneally on embryonic day 7.5 (E7.5), and the mice were sacrificed on E10.5. Embryonic tissues were collected, and the morphology of embryos in each group was observed under a stereomicroscope. The interaction between ethionine and MAT2A was analyzed using Autodock software. The expression levels of MAT2A, β-catenin, ZEB1, and EMT-related proteins in the brain tissues of embryos from the three groups were measured using immunofluorescence, immunohistochemistry, Western blotting, enzyme-linked immunosorbent assay (ELISA), and real-time quantitative polymerase chain reaction (RT-qPCR). Variance analysis was used for intergroup comparisons.Results:(1) Autodock analysis results showed that MAT2A binds to ethionine through covalent bonds, exhibiting a complementary effect, thereby accelerating the expression of MAT2A. (2) After successful construction of the NTD model, normal embryos were plump with well-developed brains. NTD embryos showed delayed development, obvious anencephaly, unclosed neural tubes, and asymmetry. (3) The levels of SAM and SAH in the embryonic tissues of the ethionine group were significantly lower than those in the normal group (1 737.56±95.64 vs. 872.33±205.11, and 89.17±9.50 vs. 51.25±9.48, respectively). The SAM and SAH levels in the ethionine+SAM group was 1 197.00±222.27 and 66.61±12.25, significantly higher than those in the ethionine group ( P<0.017). Compared with the normal group and the ethionine+SAM group, the expression of MAT2A mRNA in the embryonic brain tissue of the ethionine group was significantly upregulated (1.00±0.00, 1.59±0.52, and 2.42±0.53, respectively, F=49.64, P<0.001; pairwise comparisons between groups P<0.017). (4) Compared with the normal group, the expression of Ctnnb1 in the ethionine group was reduced, and the expression of Ctnnb1 in the ethionine+SAM group was higher than that in the ethionine group (1.00±0.00, 0.38±0.16, and 0.76±0.10, respectively, F=149.03, P<0.001; pairwise comparisons between groups P<0.017). (5) The expression of ZEB1 in the ethionine group was higher than that in the normal group and the ethionine+SAM group (2.91±0.55, 1.00±0.00, and 1.61±0.20, respectively, F=150.01, P<0.001; pairwise comparisons between groups P<0.017). (6) The expression levels of E-cadherin and Vimentin in the ethionine group were lower than those in the normal group. In contrast, the expression of N-cadherin was higher than that in the normal group. After SAM supplementation, the expression levels of E-cadherin and Vimentin were upregulated, and the expression level of N-cadherin was downregulated (0.54±0.12, 1.00±0.00, and 0.72±0.14, respectively, F=87.44; 0.53±0.17, 1.00±0.00, and 0.76±0.09, F=87.44; 3.11±0.53, 1.00±0.00, and 2.13±0.56, F=95.54; all P<0.001; pairwise comparisons within the same index group P<0.017]). Conclusions:Ethionine promotes the expression of MAT2A, leading to reduced SAM production. Ethionine regulates the level of ZEB1 by increasing MAT2A and inhibits the EMT process to interfere with methionine cycle metabolism, ultimately resulting in NTD.

Objective To investigate the clonal rearrangement characteristics and clinical application value of IGH gene in B-cell non-Hodgkin's lymphoma(B-NHL).Methods Demographic and clinical data as well as IGH sequencing results of 55 patients with B-NHL who underwent next-generation sequencing(NGS)testing were collected,and IGH gene clonal rearrangement was detected.The characteristics of IGH gene clonal rearrangement,IGHV gene usage,and the clinical application value of NGS for IGH clonal rearrangement were analyzed.Results Among 55 patients with B-NHL and IGH clonal rearrangement,single dominant clones were mainly detected(85.45%,47/55);a few patients had two(12.73%,7/55)and three dominant clones(1.82%,1/55).In terms of preference for IGHV gene usage,IGHV3 gene had the highest frequency of access in B-NHL,followed by IGHV4.Among the IGHV subtypes,IGHV3-23 had the highest frequency in chronic lymphocytic leukemia/small lymphocytic lymphoma,and IGHV4-34 had the highest frequency in primary central nervous system diffuse large B-cell lymphoma and not otherwise specified diffuse large B-cell lymphoma.Conclusion A preference for IGHV gene usage in clonal rearr-angement of IGH genes is noted in B-NHL patients with different pathological types.Using NGS to detect IGHclonal rearrangement can identify subclones and clonal correlations,and assist in disease diagnosis.

ObjectiveThe human angiotensin converting enzyme2 （hACE2） transgenic mouse model was used to clarify the antiviral efficacy of BD-77 against a novel coronavirus SARS-CoV-2 and explore the action mechanism of BD-77 against SARS-CoV-2. MethodSARS-CoV-2 Omicron and Delta variant strains-infected VeroE6 cell models were established and administered with BD-77 to observe the antiviral effect of BD-77 in vitro. A kit was used to detect the effect of BD-77 in vitro on the binding of spike S protein of SARS-CoV-2 virus （Delta/Omicron） to angiotensin converting enzyme2 （ACE2）. Chromatography was adopted to detect the binding of BD-77 to the S protein and N protein of the novel coronavirus. hACE2 transgenic C57BL/6 mice were divided into a blank control group， SARS-CoV-2 infection group， BD-77 administration groups of 37.5 mg·kg^-1 and 75 mg·kg^-1， with eight mice in each group. The pneumonia model of SARS-CoV-2-infected hACE2 transgenic mice was built to observe the survival of the mice， detect the virus titer of the lung tissue of the mice， and observe the lesions in the lung tissue. ResultBD-77 had a certain inhibitory effect on Omicron and Delta variant strains in vitro， with median inhibitory concentration （IC₅₀） of 526.3 mg·L^-1 and 653.0 mg·L^-1， respectively. BD-77 had no significant inhibitory effect on the binding of the S protein of WT， Omicron， and Delta variant strains of SARS-CoV-2 to ACE2 and had no binding effect with the S protein and N protein of the novel coronavirus. No mice in the blank group died， while the mortality rate of SARS-CoV-2-infected mice was 75%. There was a large amount of virus replication in the lung tissue of the mice and large areas of inflammatory infiltration in the lung tissue and interstitium. Compared with the model group， BD-77 administration groups of 37.5 mg·kg^-1 and 75 mg·kg^-1 could reduce the mortality of mice， significantly lower the virus titer in the lung tissue of mice （P<0.05）， and improve lung lesions. ConclusionBD-77 demonstrated significant inhibitory effects against SARS-CoV-2 virus in vitro and in vivo. However， its mechanism of action did not involve direct inhibition of the virus itself or intervention in the virus-host binding process. This finding suggests that the mechanism of action of BD-77 needs to be thoroughly investigated and elucidated by further experiments.

Objective To explore the clinical efficacy of two procedures in thoracoscopic anterior mediastinal tumor resection. Methods A retrospective study was conducted on patients who underwent thoracoscopic anterior mediastinal tumor resection at the Department of Thoracic Surgery, the 910th Hospital of Joint Logistics Support Force from October 2016 to January 2024. Patients were divided into two groups according to the surgical approach: a modified approach group (bilateral intercostal ports+two subcostal ports) and a classic subxiphoid approach group (one subxiphoid port+two subcostal ports). Perioperative data and postoperative improvement of myasthenia gravis (MG) subgroup were compared between the two groups. Results A total of 55 patients were included, including 27 males and 28 females with a mean age of (49.4±15.1) years. There were 23 patients in the modified approach group and 32 patients in the classic subxiphoid approach group. The modified approach group had shorter operation time [(129.0±20.5) min vs. (148.9±16.7) min, P<0.001], less intraoperative blood loss [(63.0±16.6) mL vs. (75.0±10.8) mL, P<0.001], shorter postoperative drainage tube removal time [(3.1±0.4) d vs. (3.9±0.6) d, P<0.001] and shorter postoperative hospital stay [(4.2±0.4) d vs. (5.0±0.6) d, P<0.001), and lower proportion of intraoperative cardiac dysfunction [4 (17.4%) vs. 14 (43.8%), P=0.040]. There was no statistical difference in maximum diameter of tumor resected [(4.5±1.7) cm vs. (4.0±0.9) cm, P=0.193] and postoperative drainage volume [(396.4±121.5) mL vs. (399.9±161.3) mL, P=0.932]. There was 1 patient of perioperative collateral injury in the modified approach group (pericardial injury), and 6 patients in the classic subxiphoid approach group (1 patient of diaphragm injury, 1 patient of liver contusion, 4 patients of pericardial injury). There was no statistical difference in pain scores at 24 h, 48 h and 72 h after surgery (P>0.05). The postoperative improvement of MG symptoms in the modified approach group was better than that in the classic subxiphoid approach group at 1 year after surgery (complete stable remission rate: 77.8% vs. 50.0%; effective rate: 100.0% vs. 91.6%). No conversion to open chest surgery occurred in either group, and there were no postoperative rehospitalizations or deaths related to surgery within 30 days after surgery in both groups. Conclusion The modified approach is safe and controllable with more open surgical field and more reliable complete resection range than the classic subxiphoid approach group.

Light adaptation enables the vertebrate visual system to operate over a wide range of ambient illumination. Regulation of phototransduction in photoreceptors is considered a major mechanism underlying light adaptation. However, various types of neurons and glial cells exist in the retina, and whether and how all retinal cells interact to adapt to light/dark conditions at the cellular and molecular levels requires systematic investigation. Therefore, we utilized single-cell RNA sequencing to dissect retinal cell-type-specific transcriptomes during light/dark adaptation in mice. The results demonstrated that, in addition to photoreceptors, other retinal cell types also showed dynamic molecular changes and specifically enriched signaling pathways under light/dark adaptation. Importantly, Müller glial cells (MGs) were identified as hub cells for intercellular interactions, displaying complex cell‒cell communication with other retinal cells. Furthermore, light increased the transcription of the deiodinase Dio2 in MGs, which converted thyroxine (T4) to active triiodothyronine (T3). Subsequently, light increased T3 levels and regulated mitochondrial respiration in retinal cells in response to light conditions. As cones specifically express the thyroid hormone receptor Thrb, they responded to the increase in T3 by adjusting light responsiveness. Loss of the expression of Dio2 specifically in MGs decreased the light responsive ability of cones. These results suggest that retinal cells display global transcriptional changes under light/dark adaptation and that MGs coordinate intercellular communication during light/dark adaptation via thyroid hormone signaling.
Animals ; Mice ; Dark Adaptation ; Light ; Retina ; Retinal Cone Photoreceptor Cells/metabolism* ; Adaptation, Ocular ; Neuroglia/physiology* ; Cell Communication ; Thyroid Hormones

Objective:Comparing the diagnostic performance of pulmonary infection pathogens between metagenomic next-generation sequencing (mNGS) testing and traditional assay in patients with AIDS to provide references for the diagnosis and treatment of the disease.Methods:From July 2019 to January 2021, the regular clinical assays as well as mNGS testing were performed for patients and those discharged with a diagnosis of AIDS and pulmonary infection were retrospectively reviewed in the department of infectious diseases of Beijing You An Hospital. The cases with discharge diagnosis of AIDS for whom mNGS testing was performed on samples from respiratory system were analyzed. Diagnostic performance of pathogens was compared between mNGS testing and traditional etiologyic diagnostic method. Diagnosis concordance analysis and diagnostic comparison study between mNGS and traditional etiology diagnosis method in terms of pathogens were also performed.Results:Fifty-five cases discharged with AIDS and pulmonary infection were enrolled.. For 29 cases for whom mNGS testing was performed on samples from respiratory system, the sensitivity of mNGS for diagnosing infection was higher than that of traditional etiology diagnosis method (89.7% vs. 37.9%, P<0.001) but with poor consistency (Kappa=0.249, P=0.170). A superior positivity rate in mNGS than that in traditional etiology diagnosis method for diagnosing bacterial (90.9% vs. 9.1%, P<0.001) Pneumocystis jirovecii (mNGS only), and nontuberculous mycobacteria (mNGS only). Conclusions:mNGS could yield a higher sensitivity for pulmonary pathogen identification in AIDS patients, especially for bacterial, Pneumocystis jirovecii and nontuberculous mycobacteria compared to traditional etiologic diagnostic method.

Motor imagery electroencephalogram (EEG) signals are non-stationary time series with a low signal-to-noise ratio. Therefore, the single-channel EEG analysis method is difficult to effectively describe the interaction characteristics between multi-channel signals. This paper proposed a deep learning network model based on the multi-channel attention mechanism. First, we performed time-frequency sparse decomposition on the pre-processed data, which enhanced the difference of time-frequency characteristics of EEG signals. Then we used the attention module to map the data in time and space so that the model could make full use of the data characteristics of different channels of EEG signals. Finally, the improved time-convolution network (TCN) was used for feature fusion and classification. The BCI competition IV-2a data set was used to verify the proposed algorithm. The experimental results showed that the proposed algorithm could effectively improve the classification accuracy of motor imagination EEG signals, which achieved an average accuracy of 83.03% for 9 subjects. Compared with the existing methods, the classification accuracy of EEG signals was improved. With the enhanced difference features between different motor imagery EEG data, the proposed method is important for the study of improving classifier performance.
Algorithms ; Brain-Computer Interfaces ; Electroencephalography/methods* ; Humans ; Imagery, Psychotherapy ; Imagination