Space medicine,as a comprehensive discipline ensuring the safety,health,and efficient performance of astronauts during manned space missions,focuses on elucidating the underlying mechanisms of multi-system physiological effects induced by extreme space environments and developing corresponding protective strategies.With China's space program transitioning into an application and development phase,space medical experiments—a critical domain within space applications—face significant opportunities and challenges.This paper reviews the international development trend in the field of medical experiments and the progress in China from perspectives including platform system construction,utilization of novel technologies,and scientific discoveries.It further outlines the engineering framework,guiding ideology,and key research directions for space medical experiments under China's Space Station Application and Development Project.Deliberations and prospects center on the in-depth analysis of the adaptation law of life in space flight,the application of big data and artificial intelligence technology,the emerging challenges it faces,and the scientific research organization models.This work aims to provide a reference for the development of space medical experiment field in China.

Objective Explore a non-contact physiological and psychological detection model based on facial video in simulations of weightlessness effects,research new methods for non-contact heart rate and negative mood state detection in long-term simulations of weightlessness effect analysis.Methods Construct a non-contact physiological and psychological data collection system for fusion analysis of visible light and thermal infrared videos.Collect physiological and psychological data of volunteers in the"Earth Star-Ⅱ"90-day head-down bed rest experiment.A non-contact heart rate detection model based on GCN facial multi-region feature fusion and a non-contact negative mood state detection model considering data reliability were constructed,and the effectiveness of the models were validated with finger clip heart rate and POMS-SF scale as labels.Results The experimental results show that the average difference in the Bland-Altman plot of the non-contact heart rate detection model is-1.26 bpm,and 96.3%of value error detection data falls within the 95%confidence interval,indicating a high consistency between the model detected heart rate and the finger clip heart rate.The non-contact negative mood state detection model achieves an accuracy of>0.85 for detecting tension,depression,anger,and fatigue.Features such as heart rate,AU06,eye gaze,and head pose were observed to be important to mood state detection.Conclusion Non-contact physiological and psychological detection methods not only can be utilized for long-term physiological analysis in simulations of weightlessness effects,but also provide a novel technical approach for on-orbit astronauts health assurance during long-term space flight in the future.

Objective To study the influence of long term simulated weightlessness on occurrence of laryngopharyngeal reflux(LPR)in healthy volunteers by detection of pepsin in saliva.Methods During a 90-day head-down tilt bed rest(HDTBR)experiment,11 volunteers(4 from the control group and 7 from the countermeasure group)were recruited in the study in the following seven sessions:before bed rest session(Pre),during bed rest sessions for 3 days(BR3),31 days(BR31),61 days(BR61),85 days(BR85)and post bed rest sessions for 7 days(R7)and 25 days(R25).During each testing session,saliva samples were collected for two consecutive days both in the morning and at night before sleeping.Then pepsin in the saliva was measured by enzyme-linked immunosorbent assay.Scale of otorhinolaryngological symptoms for the duration of"Pre-,During-and Post-"were retrospectively performed.Results Among 288 saliva samples of 11 volunteers,17 saliva samples of 8 volunteers were positive for pepsin.The incidence of LPR was 9.1%(1/11)in the Pre session,and it increased to 36.4%in the BR31 session which was higher than the following consequential sessions(0%in BR31,27.3%in BR61 and 27.3%in BR85).Intriguingly,it rose again to 45.5%in R7 session and decreased to 9.1%until in R25 session.There was no significant difference between the control group and the countermeasure group.Total scores for the scale of otorhinolaryngological symptoms showed that a slight elevation tendency emerged during HDTBR session,compared with the pre-HDTBR session.It recovered during the post bed rest sessions.Conclusion The laryngopharyngeal reflux was found in the Pre,During and Post HDTBR experiment.The incidence was significantly increased both in the BR3 and R7 sessions,which indicates that the change of the posture with the stimulation of gastrointestinal dynamic conditions,despite the changes from vertical to horizontal or from horizontal to vertical,might be the major impact factor contributing to the elevation tendency of the incidence of laryngopharyngeal reflux.

Objective:To explore the performance of the commonly used whole blood C-reactive protein (CRP) detection systems and give related recommendation on the performance requirements of detection systems.Methods:A total of 7 540 venous blood samples from 26 maternal, child and children′s hospitals were collected to conduct this multi-center study on the analytical performance of 5 commonly used whole blood CRP detection systems from March to April in 2019. The blank check, carryover, repeatability, intermediate precision, linearity, sample stability, influence of hematocrit/triglyceride/bilirubin, comparison with SIEMENS specific protein analyzer and trueness were evaluated. The 5 systems included BC-5390CRP autohematology analyzer, AstepPLUS specific protein analyzer, Ottoman-1000 Automated Specific Protein POCT Workstation, i-CHROMA Immunofluorometer equipment Reader and Orion QuikRead go detecting instrument. The 5 systems were labeled as a, b, c, d and e randomly.Results:Within the 5 systems, all values of blank check were less than 1.00 mg/L, the carryovers were lower than 1.00%. The repeatability of different ranges of CRP concentrations including 3.00-10.00, 10.00-30.00 and>30.00 mg/L were less than 10.00%, 6.00% and 5.00%, respectively, and the intermediate precision was less than 10.00%. The linearity correlation coefficients of the 5 systems were all above 0.975, while the slope was within 0.950-1.050. Whole blood samples were stable within 72 hours both at room temperature (18-25 ℃) and refrigerated temperature (2-8 ℃). The CRP results were rarely influenced by high triglyceride or bilirubin, except for the immmunoturbidimetric test based on microparticles coated with anti-human CRP F(ab) 2 fragments. When triglyceride was less than 15.46 mmol/L, the deviation of CRP was less than 10.00%. When bilirubin was less than 345.47 μmol/L, the deviation of CRP was less than 10.00%. CRP was more susceptible to Hct on the systems without Hct correction. The deviation of CRP between different Hct dilution concentration and 40% dilution concentration can reach as high as 67.48%. The correlation coefficients ( r) of 5 systems were all more than 0.975 in the range of 0-300.00 mg/L compared with Siemens specific protein analyzer. All systems passed the trueness verification using the samples with specified values of 12.89 and 30.60 mg/L. Conclusion:The performance of 5 systems can basically meet the clinical needs, but it is suggested that the whole blood CRP detection system without automatic Hct correction should be modified manually.

Objective To study the relationship between self-esteem and childhood abuse, life events among male violent adolescent. Methods According to the modified overt aggression scale, juvenile delinquents were divided into violent group (n = 128 )and nonviolent group (n = 118 ). All the participants were investigated by Self-Esteem Scale (SES), Childhood Trauma Questionnaire-28 Item Short Form (CTQ-SF) and Adolescent SelfRating Life Events (ASLEC) and conducted correlation and regression analysis. Results ①Violent group had lower self-esteem scores ( 22.73 ± 3.30 ) than the nonviolent group ( 23.81 ± 3.30, P ＜ 0.05 ). Violent group had higher scores in physical abuse, sexual abuse, total life events, interpersonal relationship, punishment, and other (8.30 ±4.07, 7.23 ±2.26, 54.48 ±18.60, 10.09 ±3.84, 14.43 ±5.87, 4.93 ±3.15, 9.93 ±3.64), compared to the nonviolent group (7.27 ± 3.27, 6.60 ± 2.09, 45.40 ± 18.45, 8.42 ± 4.13, 11.07 ± 5.75, 3.66 ±2.81, 7.84 ±3.66, P＜0. 05). ②The self-esteem was significantly negative correlated with the childhood abuse and life events( r= -0. 143 ～ -0. 358, P＜ 0.01 ) among violent male adolescents. ③The physical abuse and punishment had significant prediction function of 15.6% on self-esteem. Conclusions Violent adolescents have low self-esteem, which is closely related to childhood abuse and adolescent life events.

Histaminergic neurons solely originate from the tuberomammillary nucleus (TMN) in the posterior hypothalamus and send widespread projections to the whole brain. Experiments in rats show that histamine release in the central nervous system is positively correlated with wakefulness and the histamine released is 4 times higher during wake episodes than during sleep episodes. Endogeneous prostaglandin E2 and orexin activate histaminergic neurons in the TMN to release histamine and promote wakefulness. Conversely, prostaglandin D2 and adenosine inhibit histamine release by increasing GABA release in the TMN to induce sleep. This paper reviews the effects and mechanisms of action of the histaminergic system on sleep-wake regulation, and briefly discusses the possibility of developing novel sedative-hypnotics and wakefulness-promoting drugs related to the histaminergic system.

Dopamine(DA) modulates diverse wake-related behaviors including movement,reward, and cognition.Dopaminergic neurons are located in the substantia nigra pars compacta and ventral tegmental area.There are five distinct DA receptors(R):D_1R,D_2R(D_(2S)R and D_(2L)R), D_3R,D_4R and D_5R in the central nervous system, in which D_1R and D_2R are majorly expressed. The affinity of D_2R for endogenous DA is significantly higher than that of D_1R.Re- cently,studies by pharmacological and gene knock-out animals revealed that dopamine D_2R is essential inmaintaining wakefulness.Here,we review the progress on roles of D_2R in sleep-wake regulation.

Aim The mechanism of basic fibroblast growth factor(bFGF)in mediating increase of intracellular free magnesium ([Mg2+]i) in human umbilical vein endothelial cells (HUVECs), and the relationship between Mg2+and angiogenesis were investigated in this study.Methods The change of[Mg2+]i in HUVECs were quantitatively detected in intracellular cation measurement system via loaded with the fluorescent magnesium indicator mag-fura-2. Endothelial cells were primarily acquired by infusion of collagen enzyme solutioninto the lumens of human umbilical veins and cultured in M199 with 0.2 fetal bovine serum. The role of bFGF in angiogenesis was observed in presence of 0,1 mmol?L-1 or 2 mmol?L-1 of extracellular Mg2+.Results bFGF dose-dependently increased [Mg2+]i, and there was not any significant difference among the groups of 0,1 mmol?L-1and 2 mmol?L-1 of extracellular Mg2+;similar results were obtained in groups done with Na+ and Ca2+. Pretreatment with bFGF receptor-2 (KDR) inhibitor (SU1498) blocked the increase of [Mg2+]i induced by bFGF.Unlike in the group of 0 mmol?L-1extracellular Mg2+,the apparent angiogeneses were observed in the groups of 1 mmol?L-1 and 2 mmol?L-1 extracellular Mg2+ in the presence of bFGF.bFGF-induced angiogenesis was significantly blocked with SU1498 in the presence of 1 mmol?L-1 extracelluar Mg2+.Conclusions These results suggest that the increase of [Mg2+]i by bFGF come from intracellular Mg2+ pools mediated by KDR-dependent signaling pathways,thereby resulting in the bFGF-induced angiogenesis.