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.

ObjectiveBola-like short peptides exhibit novel self-assembly properties due to the formation of peptide dimers via hydrogen bonding interactions between their C-terminals. In this configuration, hydrophilic amino acids are distributed at both terminals, making these peptides behave similarly to Bola peptides. The electrostatic repulsive interactions arising from the hydrophilic amino acids at each terminal can be neutralized, thereby greatly promoting the lateral association of β-sheets. Consequently, assemblies with significantly larger widths are typically the dominant nanostructures for Bola-like peptides. To investigate the effect of hydrophilic amino acids on the self-assembly behavior of Bola-like peptides, the peptides Ac-RI₃-CONH₂ and Ac-HI₃-CONH₂ were designed and synthesized using the Bola-like peptide Ac-KI₃-CONH₂ as a template. Their self-assembly behavior was systematically examined. MethodsAtomic force microscopy (AFM) and transmission electron microscopy (TEM) were employed to characterize the morphology and size of the assemblies. The secondary structures of the assemblies were analyzed using circular dichroism (CD) and Fourier transform infrared (FTIR) spectroscopy. Small-angle neutron scattering (SANS) was used to obtain detailed structural information at a short-length scale. Based on these experimental results, the effects of hydrophilic amino acids on the self-assembly behavior of Bola-like short peptides were systematically analyzed, and the underlying formation mechanism was explored. ResultsThe aggregation process primarily involved three steps. First, peptide dimers were formed through hydrogen bonding interactions between their C-terminals. Within these dimers, the hydrophilic amino acids K, R, and H were positioned at both terminals, enabling the peptides to self-assemble in a manner similar to Bola peptides. Next, β-sheets were formed via hydrogen bonding interactions along the peptide backbone. Finally, self-assemblies were generated through the lateral association of β-sheets. The results demonstrated that both Ac-KI₃-CONH₂ and Ac-RI₃-CONH₂ could self-assemble into double-layer nanotubes with diameters of approximately 200 nm. These nanotubes were formed by the edge fusion of helical ribbons, which initially emerged from twisted ribbons. Notably, the primary assemblies of these peptides exhibited opposite chirality: nanofibers formed by Ac-KI₃-CONH₂ displayed left-handed chirality, whereas those formed by Ac-RI₃-CONH₂ exhibited right-handed chirality. This reversal in torsional direction was primarily attributed to the different abilities of K and R to form hydrogen bonds with water. In contrast, Ac-HI₃-CONH₂ formed narrower twisted ribbons with a significantly reduced width of approximately 30 nm, which was attributed to the strong steric hindrance caused by the imidazole rings. The multilayer height of these ribbons was mainly due to the unique structure of the imidazole rings, which can function as both hydrogen bond donors and acceptors, thereby promoting aggregate growth in the vertical direction. ConclusionThe final morphology of the self-assemblies resulted from a delicate balance of various non-covalent interactions. By altering the types of hydrophilic amino acid residues in Bola-like short peptides, the relative strength of non-covalent interactions that drive assembly formation can be effectively regulated, allowing precise control over the morphology and chirality of the assemblies. This study provides a simple and effective approach for constructing diverse self-assemblies and lays a theoretical foundation for the development of functional biomaterials.

ObjectiveTo investigate the association of the polymorphisms of the acetyl-CoA acetyltransferase 1 （ACAT1） gene and the melatonin receptor 1B （MTNR1B） gene with the susceptibility to nonalcoholic fatty liver disease （NAFLD）. MethodsA total of 164 healthy controls and 228 NAFLD patients were enrolled in this study. PCR and sequencing methods were used to determine the genotypes of the polymorphisms of the ACAT1 gene at the rs1044925 and rs1157651 loci and the MTNR1B gene at the rs10830963 locus， and fasting venous blood samples were collected for biochemical analysis. The t-test was used for comparison of normally distributed continuous data between groups， and the non-parametric Mann-Whitney U test was used for comparison of non-normally distributed continuous data between groups； the chi-square test was used for comparison of categorical data between groups. ResultsThere were no significant differences between the NAFLD group and the healthy control group in the genotype distribution of the ACAT1 gene at the rs1044925 and rs1157651 loci and the MTNR1B gene at the rs10830963 locus （all P>0.05）. The carriers of AA genotype at the rs1044925 locus of the ACAT1 gene had a significantly higher level of low-density lipoprotein than the carriers of C allele （Z=-2.08， P=0.04）， and the carriers of G allele at the rs10830963 locus of the MTNR1B gene had a significantly higher level of fasting blood glucose than the carriers of CC genotype （Z=-3.01， P<0.01）. ConclusionThe polymorphisms of the ACAT1 gene at the rs1044925 and rs1157651 loci and the MTNR1B gene at the rs10830963 locus were not associated with the susceptibility to NAFLD. The rs1044925 locus of the ACAT1 gene and the rs10830963 locus of the MTNR1B gene are associated with the levels of low-density lipoprotein and fasting blood glucose， respectively.

This article takes pectoral qi as the starting point to discuss the traditional Chinese medicine(TCM)pathogenesis as well as the diagnostic and therapeutic approach to difficult withdrawal of mechanical ventilation in mechanically ventilated patients.According to the five-viscera correlation theory,it is believed that the onset of difficult withdrawal of mechanical ventilation is closely related to pectoral qi.The core pathogenesis of difficult withdrawal of mechanical ventilation is due to the insufficiency of pectoral qi and the deficiency of the lung,spleen and kidney,and the obstruction of pectoral qi and disharmony of qi and blood contribute to the key pathogenesis.Chinese medicine treatment can be carried out by the usage of Sijunzi Tang(Four Mild-Drug Decoction),Bufei Tang(Decoction for Replenishing Lung),Shenling Baizhu San(Powder of Radix Ginseng,Poria and Rhizoma Atractylodis Macrocephalae)to supplement and benefit pectoral qi,and by the utilization of Buzhong Yiqi Tang(Decoction for Tonifying Middle Energizer and Replenishing Qi),Shengxian Tang(Decoction for Lifting the Sinking of Qi in Chest),Juyuan Jian(Decoction for Replenishing Qi and Lifting the Sunken Qi)to elevate yang and lift the sinking of Qi.Moreover,herbs for regulating qi and blood should be added,and the management of the diet and daily living based on the identification of the deficiency and excess of the five viscera is stressed,so as to enhance the success rate of withdrawal of mechanical ventilation.The exploration will provide ideas for the treatment of difficult withdrawal of mechanical ventilation with the integrated Chinese and western medicine.

Objective To analyze the morphological alterations of corpus callosum in children with spastic cerebral palsy(SCP)using three-dimensional magnetization prepared rapid acquisition gradient echo(3D-MPRAGE)technology and to investigate the correlation between morphological indexes and gross motor function.Methods Sagittal T1WI 3D-MPRAGE data was collected from 136 children with SCP(SCP group)and 132 age-and gender-matched healthy controls(HC)(HC group),and the gross motor function measure-88(GMFM-88)was applied to assess the gross motor function.Independent sample t-test was used to compare the corpus callosum surface area,volume,maximum anterior-posterior diameter,median sagittal area(total area and area of Ⅰ-Ⅴ zone)between the two groups.Partial correlation analysis was performed to calculate the correlation between morphological indexes of the corpus callosum and GMFM-88 with age as a covariate.Results Children under 3 years old,the corpus callosum surface area of the SCP group(3 914.51 mm2±1 207.97 mm2)was lower than that of the HC group(5 725.51 mm2±1 412.66 mm2).The volume of the corpus callosum(6 108.46 mm3±2 803.97 mm3)in the SCP group was lower than that of the HC group(11 297.96 mm3±4 109.02 mm3).Also,the maximum anterior-posterior diameter of the corpus callosum in the SCP group(53.40 mm±6.31 mm)was lower than that of the HC group(57.74 mm±6.04 mm)(all P<0.05).Children over 3 years old,the corpus callosum surface area of the SCP group(4 970.06 mm2±1 191.31 mm2)was lower than that of the HC group(6 372.55 mm2±1 445.59 mm2).The volume of the corpus callosum(8 330.20 mm3±2 888.20 mm3)in the SCP group was lower than that of the HC group(13 599.82 mm3±3 429.81 mm3)(all P<0.05).Partial correlation analysis showed significant correlation between corpus callosum volume,median sagittal area and gross motor score(P<0.01)with age as a covari-ate.Conclusion The 3D-MPRAGE technology can be useful for the comprehensive assessment of morphological alterations of the corpus callosum in SCP.The corpus callosum volume,and median sagittal area may become neuroimaging references for the assess-ment of motor development in cerebral palsy(CP).

Coronary artery calcification commonly results in reduced vascular compliance,facilitating incomplete stent expansion and in-stent restenosis after stent implantation,thereby leading to the failure of interventional treatment.Conventional approaches to managing calcified lesions are constrained by the intricate nature and properties of calcified plaques,which frequently pose challenges in their manipulation,consequently giving rise to numerous approaches complications and an elevated likelihood of adverse cardiovascular events following the procedure.Percutaneous coronary intraluminal shock wave balloon catheter angioplasty,also known as coronary intravascular lithotripsy,utilizing a balloon catheter system,demonstrates the capacity to safely and efficiently modify superficial and deep-seated calcifications,regardless of their concentric or eccentric nature.This intervention significantly enhances vascular compliance,thereby facilitating subsequent interventional therapies.Presently,coronary intravascular lithotripsy has emerged as a crucial approach in the management of coronary artery calcification.This article primarily offers a comprehensive examination of the mechanism of intravascular lithotripsy and the research pertaining to the treatment of coronary artery calcification.

AIM To investigate the influencing factors in scale-up of extraction process for Yunpi Xiaoshi Prescription.METHODS HPLC was adopted in the content determination of catechin,ferulic acid,taxifolin,isovitexin,narirutin,atractylenolideⅡ,naringin,morin,hesperidin,luteolin,hederagenin,atractylenolideⅠ,naringenin and hesperetin,the fingerprints were established,after which the effects of container volume,optimal fire and feeding quantity on the contents of various constituents were evaluated.RESULTS Fifteen batches of samples demonstrated the similarities of more than 0.995.Fourteen constituents showed good linear relationships within their own ranges(r>0.999 0),whose average recoveries were 96.4%-103.3%with the RSDs of 0.5%-2.7%.The influencing degree of optimal fire was greater than that of container volume and feeding quantity.CONCLUSION The combination of multi-component content determination and fingerprints can provide data basis and theoretical reference for the technology of consistency evaluation in scale-up of extraction process for Yunpi Xiaoshi Prescription.

The molecularly imprinted polymers membranes(MIPMs)were prepared for selective adsorption of lamotrigine(LTG)in plasma by surface molecular imprinting technology with polyvinylidenefluoride(PVDF)membranes as supporter,lamotrigine as template molecule,methyl methacrylate as functional monomer,ethylene glycol dimethacrylate as cross-linking agent,azodiisobutyronitrile as initiator and acetonitrile-dimethylformamide(1∶1.5,V/V)as pore-forming agent.The prepared MIPMs were characterized by scanning electron microscope,Fourier transform infrared spectroscopy,Brunaner-emmet-teller measurements,X-ray photoelectron spectroscopy,and thermogravimetric analysis.The adsorption properties of the materials were investigated by kinetic adsorption,isothermal adsorption,selective adsorption,adsorption-desorption and reusability experiments.The results showed that the imprinted layer of LTG was successfully coated on the surface of PVDF,and the materials had uniform particle size.The adsorption capacity and imprinting factor of the MIPMs towards LTG were 3.77 mg/g and 8.97,respectively.The nanomaterials showed fast mass transfer rate(30 min)and good reusability(the adsorption efficiency was 86.66%after 6 cycles),and could be used for the adsorption of LTG in plasma with low matrix interference,recoveries of 86.54%-90.48%and RSD of 1.51%-3.15%(n=5).The proposed LTG MIPMs were demonstrated to be simple and environment friendly,and had high selectivity in rapid separation and extraction of LTG in plasma.

Objective To investigate the risk factors for delayed union of extra-articular fractures of the middle and lower third of the tibia treated by locking plate.Methods Total of 135 patients of extra-articular fractures of the middle and lower third of the tibia from January 2013 to December 2018 were retrospectively analyzed,including 85 males and 50 females,ranged from 19 to 80 years old.All cases were treated with locking plates.The patients were divided into union group and delayed union group ac-cording to the condition of fracture union.The risk factors of delayed healing were determined by univariate analysis of 14 factors that might affect fracture healing first,then the factors with significance were analyzed by binary Logistic regression.Results There were 13 patients of delayed union,and the rate of delayed union was 9.63％.Univariate analysis showed that delayed union was associated with age,smoking,reduction method,anemia and time of preoperative preparation.Regression analysis showed thatage[OR=0.849,95％CI(0.755,0.954),P=0.006],smoking[OR=0.020,95％CI(0.002,0.193),P=0.001],reduction method[OR=23.924,95％CI(2.210,258.943),P=0.009],anemia[OR=0.016,95％CI(0.001,0.289),P=0.005]were the con-tributory factors for delayed union.Conclusion Young age,smoking,closed reduction and anemia are the risk factors for de-layed union of extra-articular fractures of the middle and lower third of the tibia treated by locking plate.

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.