Space radiation is the most important environmental harmful factor in long-term manned spaceflight and deep space exploration, and it may produce deterministic and stochastic effects on tissues and organs. In-depth research into the biological effects, mechanisms, and protective measures of space radiation is essential and serves as an important foundation for exploring radiation biology and promoting major manned space projects. Firstly, this review introduces the spatiotemporal distribution characteristics of space radiation during low-earth orbit flights, manned lunar landings, and deep space exploration missions, as well as the health risks and challenges it posed to astronauts. Then, it discusses medical requirements and exposure limits, risk assessment, and protection technologies included in the space radiation protection system established internationally and over 30 years of Chinese manned spaceflight departments. Finally, it outlines the subsequent work and prospects for further research.

Space radiation is the most important environmental harmful factor in long-term manned spaceflight and deep space exploration, and it may produce deterministic and stochastic effects on tissues and organs. In-depth research into the biological effects, mechanisms, and protective measures of space radiation is essential and serves as an important foundation for exploring radiation biology and promoting major manned space projects. Firstly, this review introduces the spatiotemporal distribution characteristics of space radiation during low-earth orbit flights, manned lunar landings, and deep space exploration missions, as well as the health risks and challenges it posed to astronauts. Then, it discusses medical requirements and exposure limits, risk assessment, and protection technologies included in the space radiation protection system established internationally and over 30 years of Chinese manned spaceflight departments. Finally, it outlines the subsequent work and prospects for further research.

Objective To explore the value of contrast-enhanced ultrasound(CEUS)in the assessment of diabetic microangiopademia through evaluating microcirculation perfusion of triceps surae muscle by CEUS.Method Totally 51 patients with type 2 diabetes mellitus(T2DM)admitted in our hospital between August 2020 and January 2023 were collected,including 15 pure T2DM patients and 36 T2DM patients complicated with microcirculatory disturbance(T2DM+CM).Each patient's hemoglobin A1c(HbA1c)and homeostatic model assessment for insulin resistance(HOMA-IR)were recorded.After getting enhanced intensity(PI-BI)and regional peak time(TTP-AT)by CEUS,comparative analysis between groups was conducted.Results The levels of HbA1c and HOMA-IR in T2DM+CM group were higher than those in pure T2DM group(P<0.05).TTP-AT in T2DM+CM group were longer than that in pure T2DM group of all muscles musculi gastrocnemii(MG),laterale musculi gastrocnemi(LG),soleus(SOL)and triceps surae muscle's junction region)(P<0.05).The TTP-AT of SOL was longest in both groups,followed by LG,and MG(P<0.05).The PI-BI had no significant difference among MG,LG and SOL in pure T2DM group.The PI-BI of MG was higher than that of SOL in the T2DM+CM group(P<0.05).TTP-AT of triceps surae muscle's junction region had significant positive association with both HbA1c and HOMA-IR(P<0.05).Conclusion The TTP-AT of triceps surae muscle measured by CEUS is a new indicator for evaluating microangiopathopathy in T2DM patients.

Solar proton event(SPE)is the major concern for astronauts in space radiation environment.With the coming of solar activity peak of the 25th solar cycle,the frequency of occurrence of solar proton event is increasing,as well as the intense of the events.Two SPEs of the most flux in March 23rd,2024 and June 8th,2003 and one with extra-large geomagnetic storm in May 10th,2004 were used to analysis the astronaut dose both in China Space Station orbit and lunar environment.First,radiation particle spectrum outside TianHe module was used to calculate astronauts dose inside the station,which was compared with the measured dose;second,the fitting result of proton spectrum from GOES16 satellite was used to calculate astronaut dose in lunar orbit,which was compared with the dose measured by CRaTER.Besides,the change of dose with extra shield of different material was calculated.The results indicate when no extra-large geomagnetic storm occurs,middle level SPE has no influence to astronaut in station,but an obvious dose increase happens in lunar environment,approaching ten or more mGy in skin.When shielded by Al or water of 10g/cm2,the astronaut's dose could be reduced to mGy or below.Extra energetic protons would observe on station orbit when an SPE with extra-large geomagnetic storm occurs,however when the amount of energetic protons is small,the extra dose is about several 1 nGy to 1 μGy in skin,which was negligible compared with daily dose.When a middle or above level SPE occurs,the influence to astronaut in LEO needs judge immediately,which is mostly based on the geomagnetic activity,but extra shield are needed for manned lunar exploration to ensure astronaut safety.

Objective To study the properties and antimicrobial activity of the novel self-assembled antimicrobial peptide(AMP)CR-16,and to provide experimental evidence for the treatment of bacterial infections.Methods CR-16 was designed and synthesized based on the structure of antimicrobial peptides Buforin Ⅱ and LfcinB.Dynamic light scattering(DLS),transmission electron microscopy(TEM),and X-ray diffraction(XRD)were used to characterize CR-16.Based on the results of critical micelle concentration(CMC),the self-assembled properties of CR-16 were investigated using atomic force microscopy(AFM)and circular dichroism(CD).The minimum inhibitory concentration(MIC)was used to study the inhibitory effect of CR-16 while transmission electron microscopy(TEM)was adopted to observe the interactions between CR-16 and the outer membrane of bacteria.Results AMP CR-16 was prepared as self-assemblies,which were regularly spherical in shape and stable in activity.CR-16 could inhibit both the growth of Escherichia coli and,more importantly,the growth of NDM-1-producing carbapenem-resistant Escherichia coli,promising good prospects in treating infections caused by antibiotic-resistant bacteria.Conclusion CR-16 can be self-assembled and deliver antibacterial effects against Escherichia coli.

Objective To explore the value of shear wave elastography(SWE)in the early assessment of hepatic and renal fibrosis in patients with metabolic associated fatty liver disease(MAFLD).Methods A total of 52 MAFLD patients admitted to the Second Affiliated Hospital of Wenzhou Medical University from July 2023 to May 2024 were selected as MAFLD group,and 40 non-MAFLD patients treated during the same period were served as control group.General information,laboratory data and ultrasound data were collected and compared between two groups.The differences as well as the correlation of the indicators between two groups were compared.The value of SWE in hepatic fibrosis and renal fibrosis in MAFLD patients was assessed.Results Liver function indicators,uric acid and aspartate aminotransferase-to-platelet ratio index(APRI)in MAFLD group were higher than those in control group(P＜0.01);There were no statistically significant differences between two groups in fibrosis 4 index,estimated glomerular filtration rate,serum creatinine and blood urea nitrogen(P＞0.05).The brightness of the liver,liver-kidney ratio,and liver elasticity value were higher in MAFLD group than those in control group(P＜0.05);There was no significant difference in the elasticity value of the right renal cortex between two groups(P＞0.05).Liver elasticity values was positively correlated with alanine aminotransferase(ALT);The liver-kidney ratio was positively correlated with body mass index(BMI),ALT,aspartate aminotransferase,alkaline phosphatase,y-glutamyl transferase and APRI.No significant correlation was found between the right renal cortex elasticity and BMI,estimated glomerular filtration rate,serum creatinine,blood urea nitrogen,or serum uric acid.Conclusion SWE helps in early identification of liver hardness in the MAFLD patients.But the application of SWE in early renal fibrosis in the MAFLD patients needs further evaluation.

Objective To evaluate the diagnostic value of endobronchial ultrasound-transvascular needle aspiration(EBUS-TVNA)in hilum of lung and mediastinal lesions.Methods 10 cases of hilum of lung and mediastinal lesions who underwent EBUS-TVNA because vessels pass between the airway and lesions were selected from June 2021 to January 2023,the diagnostic rate and complications were retrospectively analyzed.Results Of the 10 patients,8 traversed the pulmonary artery or its branches,2 traversed aorta or superior vena cava.Specimens were successfully obtained from all patients and 8 of them got definitive diagnosis,including 6 malignancy and 2 benign lesions.The overall yield of EBUS-TVNA for hilum of lung and mediastinal lesions was 80.0%(8/10),the diagnostic sensitivity for malignancy was 85.7%(6/7),and the diagnostic specificity was 100.0%(3/3).The other 2 cases were not diagnosed,1 was diagnosed as bladder urothelial carcinoma by percutaneous lung puncture biopsy,and the other was classified as benign due to the reduced lesion after 6 months of follow-up.All of them had good tolerance to the operation,and no serious complications occurred.Conclusion EBUS-TVNA is a safe and effective technique for the diagnosis of hilum of lung and mediastinal lesions,it can be used as an effective auxiliary method to traditional ultrasound bronchoscopy techniques.

Objective:To provide clues for in-depth research on radiation protection in deep space exploration missions by reviewing the biological effects of space radiation and biological protection technologies. Literature resource and selection 　Domestic and abroad relevant literatures were searched and reviewed. Literature quotation 　Thirty-nine papers published in China and abroad were cited. Literature synthesis 　Space radiation is the most important environmental harmful factor that affects the health and mission completion of astronauts in deep space exploration missions. It can cause multiple organ cancers throughout the body, degenerative diseases of cardiovascular, central nervous systems, and ocular lens, and acute radiation syndrome of the bone marrow, brain, and gastrointestinal tracts. The effect mechanisms include free radical production, oxidative stress, DNA and other biomolecular breaks, inflammation, cell apoptosis, and bystander effects. Biological protection can be carried out according to the characteristics of the mechanism at different stages of the development of space radiation effects. Conclusions:Deep space radiation can cause health risks such as cancer, degeneration, and acute radiation syndrome, which can be mainly protected and alleviated by reducing free radicals, promoting DNA repair, and inhibiting cell apoptosis.

Objective:To provide clues for in-depth research on radiation protection in deep space exploration missions by reviewing the biological effects of space radiation and biological protection technologies. Literature resource and selection 　Domestic and abroad relevant literatures were searched and reviewed. Literature quotation 　Thirty-nine papers published in China and abroad were cited. Literature synthesis 　Space radiation is the most important environmental harmful factor that affects the health and mission completion of astronauts in deep space exploration missions. It can cause multiple organ cancers throughout the body, degenerative diseases of cardiovascular, central nervous systems, and ocular lens, and acute radiation syndrome of the bone marrow, brain, and gastrointestinal tracts. The effect mechanisms include free radical production, oxidative stress, DNA and other biomolecular breaks, inflammation, cell apoptosis, and bystander effects. Biological protection can be carried out according to the characteristics of the mechanism at different stages of the development of space radiation effects. Conclusions:Deep space radiation can cause health risks such as cancer, degeneration, and acute radiation syndrome, which can be mainly protected and alleviated by reducing free radicals, promoting DNA repair, and inhibiting cell apoptosis.

Objective:To establish the HPLC fingerprint of Centellae herba and determine the content of asiaticoside, madecassic acid and asiaticoside B simultaneously; To compare the quality differences of Centellae herba collected in different months. Methods:The chromatographic condition was a Shimadzu InertSustain C18 column (4.6 mm×250 mm, 5 μm) with a mobile phase consisting of acetonitrile and 2 mmol/L beta cyclodextrin in gradient elution at the flow rate of 0.8 ml/min. The detection wavelength was 204 nm, and the column temperature was 30 ℃. The different Centellae herba materials of collected in 2-12 months from Chenzhou were studied by the similarity evaluation combined with cluster analysis, principal component analysis and the three contents determination. Results:The HPLC fingerprint of Centellae herba was established and 9 common peaks were designated. The eleven samples were different, which can be aggregated into 4 categories and the quality of Centellae herba collected in July was the best. Conclusion:The established fingerprint and multi-components quantitative method are stable and reliable, which can provide a reference for the quality control and the utilization of Centellae herba resource.