1.The Regulatory Mechanisms of Dopamine Homeostasis in Behavioral Functions Under Microgravity
Xin YANG ; Ke LI ; Ran LIU ; Xu-Dong ZHAO ; Hua-Lin WANG ; Lan-Qun MAO ; Li-Juan HOU
Progress in Biochemistry and Biophysics 2025;52(8):2087-2102
As China accelerates its efforts in deep space exploration and long-duration space missions, including the operationalization of the Tiangong Space Station and the development of manned lunar missions, safeguarding astronauts’ physiological and cognitive functions under extreme space conditions becomes a pressing scientific imperative. Among the multifactorial stressors of spaceflight, microgravity emerges as a particularly potent disruptor of neurobehavioral homeostasis. Dopamine (DA) plays a central role in regulating behavior under space microgravity by influencing reward processing, motivation, executive function and sensorimotor integration. Changes in gravity disrupt dopaminergic signaling at multiple levels, leading to impairments in motor coordination, cognitive flexibility, and emotional stability. Microgravity exposure induces a cascade of neurobiological changes that challenge dopaminergic stability at multiple levels: from the transcriptional regulation of DA synthesis enzymes and the excitability of DA neurons, to receptor distribution dynamics and the efficiency of downstream signaling pathways. These changes involve downregulation of tyrosine hydroxylase in the substantia nigra, reduced phosphorylation of DA receptors, and alterations in vesicular monoamine transporter expression, all of which compromise synaptic DA availability. Experimental findings from space analog studies and simulated microgravity models suggest that gravitational unloading alters striatal and mesocorticolimbic DA circuitry, resulting in diminished motor coordination, impaired vestibular compensation, and decreased cognitive flexibility. These alterations not only compromise astronauts’ operational performance but also elevate the risk of mood disturbances and motivational deficits during prolonged missions. The review systematically synthesizes current findings across multiple domains: molecular neurobiology, behavioral neuroscience, and gravitational physiology. It highlights that maintaining DA homeostasis is pivotal in preserving neuroplasticity, particularly within brain regions critical to adaptation, such as the basal ganglia, prefrontal cortex, and cerebellum. The paper also discusses the dual-edged nature of DA plasticity: while adaptive remodeling of synapses and receptor sensitivity can serve as compensatory mechanisms under stress, chronic dopaminergic imbalance may lead to maladaptive outcomes, such as cognitive rigidity and motor dysregulation. Furthermore, we propose a conceptual framework that integrates homeostatic neuroregulation with the demands of space environmental adaptation. By drawing from interdisciplinary research, the review underscores the potential of multiple intervention strategies including pharmacological treatment, nutritional support, neural stimulation techniques, and most importantly, structured physical exercise. Recent rodent studies demonstrate that treadmill exercise upregulates DA transporter expression in the dorsal striatum, enhances tyrosine hydroxylase activity, and increases DA release during cognitive tasks, indicating both protective and restorative effects on dopaminergic networks. Thus, exercise is highlighted as a key approach because of its sustained effects on DA production, receptor function, and brain plasticity, making it a strong candidate for developing effective measures to support astronauts in maintaining cognitive and emotional stability during space missions. In conclusion, the paper not only underscores the centrality of DA homeostasis in space neuroscience but also reflects the authors’ broader academic viewpoint: understanding the neurochemical substrates of behavior under microgravity is fundamental to both space health and terrestrial neuroscience. By bridging basic neurobiology with applied space medicine, this work contributes to the emerging field of gravitational neurobiology and provides a foundation for future research into individualized performance optimization in extreme environments.
2.Multicenter study on etiological characteristics of bacterial meningitis in infants aged < 90 days.
Ying LIU ; Xue FENG ; Jin GAO ; Ying XIONG ; Chang LIU ; Xin-Lin HOU
Chinese Journal of Contemporary Pediatrics 2025;27(6):648-653
OBJECTIVES:
To investigate the etiological characteristics of bacterial meningitis (BM) in infants aged <90 days.
METHODS:
A retrospective analysis was conducted on the etiology and outcomes of BM in infants aged <90 days admitted to five collaborating hospitals between January 2007 and December 2021. The overall etiological profile was described, and pathogen distributions were compared across different age groups, regions, and years. The prognosis of BM caused by common pathogens was also evaluated.
RESULTS:
A total of 197 infants with bacteriologically confirmed BM were included. The most common pathogens were Escherichia coli (E. coli) (72 cases, 36.5%), group B Streptococcus (GBS) (49 cases, 24.9%), and Listeria monocytogenes (LM) (11 cases, 5.6%). The detection rate of E. coli was significantly higher in the neonatal group than in the infant group (40.2% vs 18.2%, P<0.05). E. coli was the predominant pathogen in Beijing (31.7%) and Kunming (54.1%), while GBS and E. coli were equally prevalent in Shenzhen (33.3%). From 2018 to 2021, the detection rates of E. coli were 46.4%, 47.2%, 45.2%, and 36.8%, respectively, whereas those of GBS were 25.0%, 27.8%, 22.6%, and 31.6%. No significant difference was observed in the overall complication rates among BM cases caused by E. coli, GBS, and LM (P>0.05). However, ventriculitis and hydrocephalus were more frequent in LM meningitis than in GBS meningitis (P<0.017).
CONCLUSIONS
E. coli is the most common pathogen in BM among young infants, particularly neonates. GBS is predominant in Shenzhen, with an increasing trend. LM meningitis accounts for a notable proportion of cases and is associated with poorer outcomes.
Humans
;
Meningitis, Bacterial/microbiology*
;
Infant
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Retrospective Studies
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Infant, Newborn
;
Male
;
Female
3.A small molecule cryptotanshinone induces non-enzymatic NQO1-dependent necrosis in cancer cells through the JNK1/2/Iron/PARP/calcium pathway.
Ying HOU ; Bingling ZHONG ; Lin ZHAO ; Heng WANG ; Yanyan ZHU ; Xianzhe WANG ; Haoyi ZHENG ; Jie YU ; Guokai LIU ; Xin WANG ; Jose M MARTIN-GARCIA ; Xiuping CHEN
Acta Pharmaceutica Sinica B 2025;15(2):991-1006
Human NAD(P)H: quinone oxidoreductase 1 (NQO1) is a flavoenzyme expressed at high levels in multiple solid tumors, making it an attractive target for anticancer drugs. Bioactivatable drugs targeting NQO1, such as β-lapachone (β-lap), are currently in clinical trials for the treatment of cancer. β-Lap selectively kills NQO1-positive (NQO1+) cancer cells by inducing reactive oxygen species (ROS) via catalytic activation of NQO1. In this study, we demonstrated that cryptotanshinone (CTS), a naturally occurring compound, induces NQO1-dependent necrosis without affecting NQO1 activity. CTS selectively kills NQO1+ cancer cells by inducing NQO1-dependent necrosis. Interestingly, CTS directly binds to NQO1 but does not activate its catalytic activity. In addition, CTS enables activation of JNK1/2 and PARP, accumulation of iron and Ca2+, and depletion of ATP and NAD+. Furthermore, CTS selectively suppressed tumor growth in the NQO1+ xenograft models, which was reversed by NQO1 inhibitor and NQO1 shRNA. In conclusion, CTS induces NQO1-dependent necrosis via the JNK1/2/iron/PARP/NAD+/Ca2+ signaling pathway. This study demonstrates the non-enzymatic function of NQO1 in inducing cell death and provides new avenues for the design and development of NQO1-targeted anticancer drugs.
4.Expert consensus on apical microsurgery.
Hanguo WANG ; Xin XU ; Zhuan BIAN ; Jingping LIANG ; Zhi CHEN ; Benxiang HOU ; Lihong QIU ; Wenxia CHEN ; Xi WEI ; Kaijin HU ; Qintao WANG ; Zuhua WANG ; Jiyao LI ; Dingming HUANG ; Xiaoyan WANG ; Zhengwei HUANG ; Liuyan MENG ; Chen ZHANG ; Fangfang XIE ; Di YANG ; Jinhua YU ; Jin ZHAO ; Yihuai PAN ; Shuang PAN ; Deqin YANG ; Weidong NIU ; Qi ZHANG ; Shuli DENG ; Jingzhi MA ; Xiuping MENG ; Jian YANG ; Jiayuan WU ; Yi DU ; Junqi LING ; Lin YUE ; Xuedong ZHOU ; Qing YU
International Journal of Oral Science 2025;17(1):2-2
Apical microsurgery is accurate and minimally invasive, produces few complications, and has a success rate of more than 90%. However, due to the lack of awareness and understanding of apical microsurgery by dental general practitioners and even endodontists, many clinical problems remain to be overcome. The consensus has gathered well-known domestic experts to hold a series of special discussions and reached the consensus. This document specifies the indications, contraindications, preoperative preparations, operational procedures, complication prevention measures, and efficacy evaluation of apical microsurgery and is applicable to dentists who perform apical microsurgery after systematic training.
Microsurgery/standards*
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Humans
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Apicoectomy
;
Contraindications, Procedure
;
Tooth Apex/diagnostic imaging*
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Postoperative Complications/prevention & control*
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Consensus
;
Treatment Outcome
5.Expert consensus on management of instrument separation in root canal therapy.
Yi FAN ; Yuan GAO ; Xiangzhu WANG ; Bing FAN ; Zhi CHEN ; Qing YU ; Ming XUE ; Xiaoyan WANG ; Zhengwei HUANG ; Deqin YANG ; Zhengmei LIN ; Yihuai PAN ; Jin ZHAO ; Jinhua YU ; Zhuo CHEN ; Sijing XIE ; He YUAN ; Kehua QUE ; Shuang PAN ; Xiaojing HUANG ; Jun LUO ; Xiuping MENG ; Jin ZHANG ; Yi DU ; Lei ZHANG ; Hong LI ; Wenxia CHEN ; Jiayuan WU ; Xin XU ; Jing ZOU ; Jiyao LI ; Dingming HUANG ; Lei CHENG ; Tiemei WANG ; Benxiang HOU ; Xuedong ZHOU
International Journal of Oral Science 2025;17(1):46-46
Instrument separation is a critical complication during root canal therapy, impacting treatment success and long-term tooth preservation. The etiology of instrument separation is multifactorial, involving the intricate anatomy of the root canal system, instrument-related factors, and instrumentation techniques. Instrument separation can hinder thorough cleaning, shaping, and obturation of the root canal, posing challenges to successful treatment outcomes. Although retrieval of separated instrument is often feasible, it carries risks including perforation, excessive removal of tooth structure and root fractures. Effective management of separated instruments requires a comprehensive understanding of the contributing factors, meticulous preoperative assessment, and precise evaluation of the retrieval difficulty. The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes. The current manuscript provides a framework for understanding the causes, risk factors, and clinical management principles of instrument separation. By integrating effective strategies, endodontists can enhance decision-making, improve endodontic treatment success and ensure the preservation of natural dentition.
Humans
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Root Canal Therapy/adverse effects*
;
Consensus
;
Root Canal Preparation/adverse effects*
6.Glutamine signaling specifically activates c-Myc and Mcl-1 to facilitate cancer cell proliferation and survival.
Meng WANG ; Fu-Shen GUO ; Dai-Sen HOU ; Hui-Lu ZHANG ; Xiang-Tian CHEN ; Yan-Xin SHEN ; Zi-Fan GUO ; Zhi-Fang ZHENG ; Yu-Peng HU ; Pei-Zhun DU ; Chen-Ji WANG ; Yan LIN ; Yi-Yuan YUAN ; Shi-Min ZHAO ; Wei XU
Protein & Cell 2025;16(11):968-984
Glutamine provides carbon and nitrogen to support the proliferation of cancer cells. However, the precise reason why cancer cells are particularly dependent on glutamine remains unclear. In this study, we report that glutamine modulates the tumor suppressor F-box and WD repeat domain-containing 7 (FBW7) to promote cancer cell proliferation and survival. Specifically, lysine 604 (K604) in the sixth of the 7 substrate-recruiting WD repeats of FBW7 undergoes glutaminylation (Gln-K604) by glutaminyl tRNA synthetase. Gln-K604 inhibits SCFFBW7-mediated degradation of c-Myc and Mcl-1, enhances glutamine utilization, and stimulates nucleotide and DNA biosynthesis through the activation of c-Myc. Additionally, Gln-K604 promotes resistance to apoptosis by activating Mcl-1. In contrast, SIRT1 deglutaminylates Gln-K604, thereby reversing its effects. Cancer cells lacking Gln-K604 exhibit overexpression of c-Myc and Mcl-1 and display resistance to chemotherapy-induced apoptosis. Silencing both c-MYC and MCL-1 in these cells sensitizes them to chemotherapy. These findings indicate that the glutamine-mediated signal via Gln-K604 is a key driver of cancer progression and suggest potential strategies for targeted cancer therapies based on varying Gln-K604 status.
Glutamine/metabolism*
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Myeloid Cell Leukemia Sequence 1 Protein/genetics*
;
Humans
;
Proto-Oncogene Proteins c-myc/genetics*
;
Cell Proliferation
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Signal Transduction
;
Neoplasms/pathology*
;
F-Box-WD Repeat-Containing Protein 7/genetics*
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Cell Survival
;
Cell Line, Tumor
;
Apoptosis
7.Expert consensus on the diagnosis and treatment of osteoporotic proximal humeral fracture with integrated traditional Chinese and Western medicine (version 2024)
Xiao CHEN ; Hao ZHANG ; Man WANG ; Guangchao WANG ; Jin CUI ; Wencai ZHANG ; Fengjin ZHOU ; Qiang YANG ; Guohui LIU ; Zhongmin SHI ; Lili YANG ; Zhiwei WANG ; Guixin SUN ; Biao CHENG ; Ming CAI ; Haodong LIN ; Hongxing SHEN ; Hao SHEN ; Yunfei ZHANG ; Fuxin WEI ; Feng NIU ; Chao FANG ; Huiwen CHEN ; Shaojun SONG ; Yong WANG ; Jun LIN ; Yuhai MA ; Wei CHEN ; Nan CHEN ; Zhiyong HOU ; Xin WANG ; Aiyuan WANG ; Zhen GENG ; Kainan LI ; Dongliang WANG ; Fanfu FANG ; Jiacan SU
Chinese Journal of Trauma 2024;40(3):193-205
Osteoporotic proximal humeral fracture (OPHF) is one of the common osteoporotic fractures in the aged, with an incidence only lower than vertebral compression fracture, hip fracture, and distal radius fracture. OPHF, secondary to osteoporosis and characterized by poor bone quality, comminuted fracture pattern, slow healing, and severely impaired shoulder joint function, poses a big challenge to the current clinical diagnosis and treatment. In the field of diagnosis, treatment, and rehabilitation of OPHF, traditional Chinese and Western medicine have accumulated rich experience and evidence from evidence-based medicine and achieved favorable outcomes. However, there is still a lack of guidance from a relevant consensus as to how to integrate the advantages of the two medical systems and achieve the integrated diagnosis and treatment. To promote the diagnosis and treatment of OPHF with integrated traditional Chinese and Western medicine, relevant experts from Orthopedic Expert Committee of Geriatric Branch of Chinese Association of Gerontology and Geriatrics, Youth Osteoporosis Group of Orthopedic Branch of Chinese Medical Association, Osteoporosis Group of Orthopedic Surgeon Branch of Chinese Medical Doctor Association, and Osteoporosis Committee of Shanghai Association of Integrated Traditional Chinese and Western Medicine have been organized to formulate Expert consensus on the diagnosis and treatment of osteoporotic proximal humeral fracture with integrated traditional Chinese and Western medicine ( version 2024) by searching related literatures and based on the evidences from evidence-based medicine. This consensus consists of 13 recommendations about the diagnosis, treatment and rehabilitation of OPHF with integrated traditional Chinese medicine and Western medicine, aimed at standardizing, systematizing, and personalizing the diagnosis and treatment of OPHF with integrated traditional Chinse and Western medicine to improve the patients ′ function.
8.Endo-beta-N-acetylglucosaminidase: Possible Functions and Mechanisms
Xin-Rong LU ; Yong-Liang TONG ; Wei-Li KONG ; Lin ZOU ; Dan-Feng SHEN ; Shao-Xian LÜ ; Rui-Jie LIU ; Shao-Xing ZHANG ; Yu-Xin ZHANG ; Lin-Lin HOU ; Gui-Qin SUN ; Li CHEN
Progress in Biochemistry and Biophysics 2024;51(5):985-999
Endo-beta-N-acetylglucosaminidase (ENGase) is widely distributed in various organisms. The first reported ENGase activity was detected in Diplococcus pneumoniae in 1971. The protein (Endo D) was purified and its peptide sequence was determined in 1974. Three ENGases (Endo F1-F3) were discovered in Flavobacterium meningosepticum from 1982 to 1993. After that, the activity was detected from different species of bacteria, yeast, fungal, plant, mice, human, etc. Multiple ENGases were detected in some species, such as Arabidopsis thaliana and Trichoderma atroviride. The first preliminary crystallographic analysis of ENGase was conducted in 1994. But to date, only a few ENGases structures have been obtained, and the structure of human ENGase is still missing. The currently identified ENGases were distributed in the GH18 or GH85 families in Carbohydrate-Active enZyme (CAZy) database. GH18 ENGase only has hydrolytic activity, but GH85 ENGase has both hydrolytic and transglycosylation activity. Although ENGases of the two families have similar (β/α)8-TIM barrel structures, the active sites are slightly different. ENGase is an effective tool for glycan detection andglycan editing. Biochemically, ENGase can specifically hydrolyze β‑1,4 glycosidic bond between the twoN-acetylglucosamines (GlcNAc) on core pentasaccharide presented on glycopeptides and/or glycoproteins. Different ENGases may have different substrate specificity. The hydrolysis products are oligosaccharide chains and a GlcNAc or glycopeptides or glycoproteins with a GlcNAc. Conditionally, it can use the two products to produce a new glycopeptides or glycoprotein. Although ENGase is a common presentation in cell, its biological function remains unclear. Accumulated evidences demonstrated that ENGase is a none essential gene for living and a key regulator for differentiation. No ENGase gene was detected in the genomes of Saccharomyces cerevisiae and three other yeast species. Its expression was extremely low in lung. As glycoproteins are not produced by prokaryotic cells, a role for nutrition and/or microbial-host interaction was predicted for bacterium produced enzymes. In the embryonic lethality phenotype of the Ngly1-deficient mice can be partially rescued by Engase knockout, suggesting down regulation of Engase might be a solution for stress induced adaptation. Potential impacts of ENGase regulation on health and disease were presented. Rabeprazole, a drug used for stomach pain as a proton inhibitor, was identified as an inhibitor for ENGase. ENGases have been applied in vitro to produce antibodies with a designated glycan. The two step reactions were achieved by a pair of ENGase dominated for hydrolysis of substrate glycoprotein and synthesis of new glycoprotein with a free glycan of designed structure, respectively. In addition, ENGase was also been used in cell surface glycan editing. New application scenarios and new detection methods for glycobiological engineering are quickly opened up by the two functions of ENGase, especially in antibody remodeling and antibody drug conjugates. The discovery, distribution, structure property, enzymatic characteristics and recent researches in topical model organisms of ENGase were reviewed in this paper. Possible biological functions and mechanisms of ENGase, including differentiation, digestion of glycoproteins for nutrition and stress responding were hypothesised. In addition, the role of ENGase in glycan editing and synthetic biology was discussed. We hope this paper may provide insights for ENGase research and lay a solid foundation for applied and translational glycomics.
9.The Cell Division Cycle 73(Cdc73)Deletion Mutant Inhibits Sexual Reproduction and Mitosis of Fission Yeast Cells
Meng-Nan LIU ; Xin BAI ; Wen YU ; Xin-Lin LI ; Xiang DING ; Yi-Ling HOU
Chinese Journal of Biochemistry and Molecular Biology 2024;40(6):807-818
The cdc73(cell division cycle 73)gene encodes the RNA polymerase Ⅱ cofactor Cdc73 in fis-sion yeast(Schizosaccharomyces Pombe),and is involved in G2 checkpoint activation and regulates the cell cycle.However,whether Cdc73 regulates cell mitotic dynamics is unknown.In this study,fluores-cent protein labeling and live cell imaging techniques were used to investigate the effects of cdc73 deletion on sexual reproduction and the dynamics of microtubules,actin,mitochondria,and histones during mito-sis.The results showed that in sexual reproduction,cdc73 deletion resulted in a 14.23%increase in the length of ascospores and a 64.08%decrease in the number of cells producing four spores.Analysis of the live cell imaging results revealed that,in mitosis,the elongation length of microtubules in anaphase was shortened by 11.21%,and the elongation time was reduced by 17.39%;the formation and contraction rates of actin rings decreased by 33.33%and 26.09%,respectively,and the formation and contraction times were prolonged by 58.00%and 40.38%,respectively.Meanwhile,the expression levels of actin ring,mitochondrion,and histones also increased.This study revealed the cdc73 deletion inhibits spindle elongation and delays actin ring formation and contraction in mitosis,which provides some scientific basis for further exploring the involvement of Cdc73 in regulating microtubule and actin dynamics in cell divi-sion.
10.Research on the application of immersive teaching combined with closed-loop assessment in respiratory medicine internship teaching
Xuemei MA ; Shanshan LIANG ; Yang LIN ; Shumin LI ; Xin ZHAO ; Xia HOU
Chinese Journal of Medical Education Research 2024;23(6):800-803
Objective:To explore the application effect of immersive teaching combined with closed-loop assessment in respiratory medicine internship teaching.Methods:A total of 140 students who interned in the Department of Respiratory Medicine from August 2021 to August 2023 were selected as research subjects. They were assigned to a control group and an observation group based on the time of admission, with 70 students in each group. The control group received traditional teaching, while the observation group received immersive teaching combined with closed-loop assessment. After the internship, the theories, clinical diagnosis and treatment, operation skills, empathy ability, and teaching effectiveness of the two groups of students were compared and evaluated.Results:The scores of theories, clinical diagnosis and treatment, and operation skills were significantly higher in the observation group than in the control group ( P<0.001). The observation group scored significantly higher on the empathy scale than the control group [(73.83±6.71) vs. (61.08±6.32); t=15.60, P<0.001]. The recognition rates of the observation group students were significantly higher in learning interest, self-learning ability, comprehensive analysis ability of diseases, clinical thinking ability, independent discovery, analysis, and problem-solving ability, and team collaboration ability, as compared with the control group ( P<0.05). Conclusions:Immersive teaching combined with closed-loop assessment is beneficial for improving the theoretical and practical levels of respiratory medicine students, enhancing their empathy and comprehensive analysis abilities, and improving clinical teaching effectiveness.

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