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.

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.

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.

Aim To investigate the mechanism of py-roptosis mediated by the NLRP3/caspase-1/GSDMD signaling pathway and the intervention effect of Radix Angelica Sinensis and Radix Astragalus ultrafiltration extract(RAS-RA)in radiation-induced pulmonary fi-brosis.Methods Fifty Wistar rats were randomly di-vided into five groups,with ten rats in each group.Ex-cept for the blank control group,all other groups of rats were anesthetized and received a single dose of 40 Gy X-ray local chest radiation to establish a radiation-in-duced pulmonary fibrosis rat model.After radiation,the rats in the RAS-RA intervention groups were orally administered doses of 0.12,0.24 and 0.48 g·kg-1 once a day for 30 days.The average weight and lung index of the rats were observed after 30 days of contin-uous administration.Hydroxyproline(HYP)content in lung tissue was determined by hydrolysis method.The levels of IL-18 and IL-1 β in serum were detected by ELISA.Lung tissue pathological changes were ob-served by HE and Masson staining.Ultrastructural changes in lung tissue were observed by transmission e-lectron microscopy.The expression levels of NLRP3/caspase-1/GSDMD pyroptosis pathway-related proteins and fibrosis-related proteins in lung tissue were detec-ted by Western blot.Results Compared with the blank group,the HYP content in lung tissue and the levels of IL-18 and IL-1 β in serum significantly in-creased in the model group(P＜0.01).HE and Mas-son staining showed inflammatory cell infiltration and collagen fiber deposition.Transmission electron mi-croscopy revealed increased damaged mitochondria,disordered arrangement,irregular morphology,shallow matrix,outer membrane rupture,mostly fractured and shortened cristae,mild expansion,increased electron density of individual mitochondrial matrix,mild sparse structure of lamellar bodies,partial disorder,unclear organelles,and characteristic changes of pyroptosis.Western blot analysis showed increased expression of caspase-1,GSDMD,NLRP3,CoL-Ⅰ,α-SMA,and CoL-Ⅲ proteins(P＜0.01).Compared with the model group,the RAS-RA intervention group showed signifi-cant improvement in body mass index and lung index of rats,decreased levels of IL-18 and IL-1 β inflammatory factors(P＜0.01),improved mitochondrial structure,reduced degree of fibrosis,and decreased expression of caspase-1,GSDMD,NLRP3,COL-Ⅰ,COL-Ⅲ,and α-SMA proteins in lung tissue(P＜0.01).Conclusion RAS-RA has an inhibitory effect on radiation-in-duced pulmonary fibrosis,and its mechanism may be related to the inhibition of pyroptosis through the regu-lation of the NLRP3/caspase-1/GSDMD signaling pathway.

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 levels of regulatory T cells(Tregs)and cytokines IL-35,TGF-β and IL-10 in peripheral blood of hemophilia A(HA)patients with F Ⅷ inhibitor and their clinical significance.Methods:43 HA patients admitted to the Hematology Department of the Affiliated Hospital of North China University of Science and Technology from October 2019 to December 2020 were selected,including 6 cases with F Ⅷ inhibitor and 37 cases without FⅧ inhibitor.In addition,20 healthy males who underwent physical examinations were selected as healthy controls.Flow cytometry was used to detect the levels of CD4+CD25+CD127-Tregs in peripheral blood of the HA patients and healthy controls,and ELISA assay was used to detect the expression levels of IL-35,TGF-β and IL-10 in serum,and their differences between different groups were compared.Results:Compared with the healthy control group,the level of Tregs in HA patients was decreased,and the level of Tregs in the FⅧ inhibitor positive group was the lowest,the difference was statistically significant(P＜0.05).There was no significant difference in the expression level of Tregs in HA patients of different severity levels.The serum IL-35,TGF-β,and IL-10 levels in both FⅧ inhibitor negative and positive groups were significantly lower than those in healthy control group,and those in FⅧ inhibitor positive group were significantly lower than those in FⅧ inhibitor negative group(all P＜0.05).Conclusion:The decrease of Tregs,IL-35,TGF-β,and IL-10 levels in HA patients may be related to the formation of FⅧ inhibitors.

Objective:To evaluate the clinical characteristics and risk factors of infections occurring during hospitalization in patients with multiple myeloma (MM) treated with new generation therapies (including immuno-modulatory drugs,proteasome inhibitors and monoclonal antibodies).Methods:The clinical data were collected from 155 patients with multiple myeloma who were treated in Shanxi Bethune Hospital from March,2017 to March,2022 and were retrospectively analyzed.For this study,the following therapies were considered to be new generation therapies:lenalidomide,pomadomide,bortezomib,ixazomib,daratumumab. The clinical characteristics and risk factors of infection were analyzed.Results:A total of 155 patients were included in this study.The median follow-up time was 20 months.Of 155 patients with MM,242 infection episodes were identified.Among the 242 infections,the incidence of clinically defined infection (CDI)was the highest (186,76.86％),followed by microbiologically defined infection (MDI)in 50 cases (20.66％),and fever at unknown focus (FUF)in 6 cases (2.48％).35 cases (14.46％)of bacteria,10 cases (4.13％)of viruses,and 5 cases (2. 07％)of fungi were clearly infected.The most common site of infection was the lower respiratory tract in 90 cases (37.19％),the upper respiratory tract in 83 cases (34.30％),and the digestive tract in 27 cases (11.16％).All-cause mortality was 8.39％(13/155).In univariate analysis,there was a higher correlation between ISS stage Ⅲ,the number of treatment lines ≥2,frail and infected patients with multiple myeloma.In multivariate analysis,ISS stage Ⅲ(OR=2.96,95％CI:1.19-7.40,P=0.02),the number of treatment lines ≥2 (OR=2.91,95％CI:1.13-7.51,P=0.03)and frail (OR=3.58,95％CI:1.44-8.89,P=0. 01)were risk factors for infection in patients with multiple myeloma in the era of new drugs.Conclusion:Patients with multiple myeloma treated with new agents are prone to bacterial infection during hospitalization.ISS stage Ⅲ,lines of therapy(≥2)and frail were associated with high risk for infection.

Purpose: This study aimed to investigate the effect of the N6-methyladenosine (m6A) dependent ferroptosis on cisplatininduced Sertoli cell injury. Materials and Methods: A cisplatin exposure mouse model was established by intraperitoneal injection of cisplatin in our study. TM4 cell lines was used for in vitro study. Ferroptosis was detected according to metabolomic analysis and a series of assays, including malondialdehyde, glutathione, and glutathione disulfide concentration detection, 2′,7′-dichlorodihydrofluorescein diacetate and BODIPY 581/591 C11 probe detection, and transmission electron microscope imaging. Key ferroptosis-related genes were identified via transcriptomic analysis, western blot and immunohistochemistry. The m6A modification was demonstrated via m6A RNA immunoprecipitation and luciferase reporter assays. Immune cell infiltration was detected by mass cytometry, and verified by flow cytometry and immunofluorescence. Results: Ferroptosis, but not other types of programmed cell death, is a significant phenomenon in cisplatin-induced testis damage and Sertoli cell loss. Ferroptosis induced by cisplatin in Sertoli cell/TM4 cell is GPX4 independent but is regulated by SLC7A11 and ALOX12. Both SLC7A11 and ALOX12 are regulated via m6A dependent manner by METTL3. Furthermore, overexpressed ALOX12-12HETE pathway may result in macrophage polarization and inflammatory response in cisplatin exposure testis. Conclusions Cisplatin-induced Sertoli cell injury via ferroptosis and promoted ferroptosis in an m6A dependent manner. m6A modification of both SLC7A11 and ALOX12 mRNA could result in ferroptosis in our in vitro model. Further, overexpressed ALOX12 can cause more production of 12-HETE, which may be responsible for testis inflammation caused by cisplatin.

Objective:To investigate the relationship between sarcopenia and the long-term prognosis of elderly patients with locally advanced colorectal cancer.Methods:A retrospective analysis was conducted on clinical data from 205 elderly colorectal cancer patients aged 70 years and above who underwent radical resection with TNM staging of stage Ⅱ to Ⅲ at Beijing Hospital between January 2014 and December 2018.The study utilized abdominal CT scans taken within 30 days before surgery to measure the skeletal muscle area(SMA)of the 3rd lumbar vertebrae cross-section.Sarcopenia was defined as a skeletal muscle index(SMI) of ≤52.4 cm 2/m 2 in men and ≤38.5 cm 2/m 2 in women(SMI=SMA/height 2).A comparison was made between the clinical and pathological conditions of patients with and without sarcopenia in the two groups, with an analysis of the impact of sarcopenia on the long-term prognosis of elderly postoperative colorectal cancer patients. Results:Among the 205 patients assessed, 63.4%(130/205)were diagnosed with sarcopenia.The group with sarcopenia had a higher percentage of individuals aged 80 years and older( χ2=6.420, P=0.011)compared to those without sarcopenia.Additionally, this group had a lower proportion of overweight or obese patients( χ2=9.366, P=0.009), fewer patients who underwent adjuvant chemotherapy, and a lower 5-year disease-free survival rate post-surgery( χ2=6.257, 7.347, P=0.012, 0.007).Kaplan-Meier analysis indicated that disease-free survival rate was better in elderly patients with locally advanced colorectal cancer who did not have sarcopenia compared to those with sarcopenia(Log-rank χ2=6.919, P=0.009).Moreover, in elderly patients without sarcopenia, those who received adjuvant chemotherapy had a more favorable disease-free survival outcome than those who did not receive such treatment(Log-rank χ2=4.745, P=0.029).Multifactorial Cox regression analysis showed that TNM stage Ⅲ( HR=1.634, 95% CI: 1.110-2.404, P=0.013)and the presence of sarcopenia( HR=1.509, 95% CI: 1.017-2.238, P=0.041)were significant factors influencing the poor long-term prognosis of elderly patients with locally advanced colorectal cancer. Conclusions:Sarcopenia is associated with aging and body mass index, and has been found to be a significant factor in the long-term prognosis of elderly colorectal cancer patients.Those with sarcopenia tend to have a poorer prognosis, while those without may experience benefits from adjuvant chemotherapy.

Objective:To investigate the clinical features and therapeutic efficacy of patients with hereditary leiomyomatosis and renal cell carcinoma(RCC) syndrome-associated RCC (HLRCC-RCC) in China.Methods:The clinical data of 119 HLRCC-RCC patients with fumarate hydratase (FH) germline mutation confirmed by genetic diagnosis from 15 medical centers nationwide from January 2008 to December 2021 were retrospectively analyzed. Among them, 73 were male and 46 were female. The median age was 38(13, 74) years. The median tumor diameter was 6.5 (1.0, 20.5) cm. There were 38 cases (31.9%) in stage Ⅰ-Ⅱand 81 cases (68.1%) in stage Ⅲ-Ⅳ. In this group, only 11 of 119 HLRCC-RCC patients presented with skin smooth muscle tumors, and 44 of 46 female HLRCC-RCC patients had a history of uterine fibroids. The pathological characteristics, treatment methods, prognosis and survival of the patients were summarized.Results:A total of 86 patients underwent surgical treatment, including 70 cases of radical nephrectomy, 5 cases of partial nephrectomy, and 11 cases of reductive nephrectomy. The other 33 patients with newly diagnosed metastasis underwent renal puncture biopsy. The results of genetic testing showed that 94 patients had FH gene point mutation, 18 had FH gene insertion/deletion mutation, 4 had FH gene splicing mutation, 2 had FH gene large fragment deletion and 1 had FH gene copy number mutation. Immunohistochemical staining showed strong 2-succinocysteine (2-SC) positive and FH negative in 113 patients. A total of 102 patients received systematic treatment, including 44 newly diagnosed patients with metastasis and 58 patients with postoperative metastasis. Among them, 33 patients were treated with tyrosine kinase inhibitor (TKI) combined with immune checkpoint inhibitor (ICI), 8 patients were treated with bevacizumab combined with erlotinib, and 61 patients were treated with TKI monotherapy. Survival analysis showed that the median progression-free survival (PFS) of TKI combined with ICI was 18 (5, 38) months, and the median overall survival (OS) was not reached. The median PFS and OS were 12 (5, 14) months and 30 (10, 32) months in the bevacizumab combined with erlotinib treatment group, respectively. The median PFS and OS were 10 (3, 64) months and 44 (10, 74) months in the TKI monotherapy group, respectively. PFS ( P=0.009) and OS ( P=0.006) in TKI combined with ICI group were better than those in bevacizumab combined with erlotinib group. The median PFS ( P=0.003) and median OS ( P=0.028) in TKI combined with ICI group were better than those in TKI monotherapy group. Conclusions:HLRCC-RCC is rare but has a high degree of malignancy, poor prognosis and familial genetic characteristics. Immunohistochemical staining with strong positive 2-SC and negative FH can provide an important basis for clinical diagnosis. Genetic detection of FH gene germ line mutation can confirm the diagnosis. The preliminary study results confirmed that TKI combined with ICI had a good clinical effect, but it needs to be confirmed by the results of a large sample multi-center randomized controlled clinical study.