Objective Accurate speed perception is crucial for tasks such as man-controlled rendezvous and docking,and teleoperation of space manipulator.Therefore,it is necessary to conduct in-orbit experiments to explore the influence of long-term spaceflight on human speed perception characteristics.Methods The Time-to-Collision(TTC)paradigm was selected to develop experimental software,using a tablet computer for stimulus presentation.Human speed perception characteristics were evaluated based on the subjects'keystroke response data on the keyboard.Through ground-based experiments,the usability and reliability of the paradigm were explored,and the gravity internal model effect was quantitatively analyzed.Through in-orbit experiments on space station tasks,the influence of long-term spaceflight on human speed perception characteristics was further investigated.Results Under the 1G environment on the ground,the TTC paradigm has a high test-retest reliability(r>0.8),and indicators such as average deviation rate and absolute value of average deviation rate show no practice effect.In addition,ground experiments found that compared to vertical upward movement,vertical downward movement is estimated to be faster(i.e.,keystroke time is advanced),showing the existence of the gravity internal model effect.In the microgravity environment of spaceflight,there are no significant differences in average deviation rate and absolute value of average deviation rate among three stages(pre-flight,in-flight,post-flight)and seven tests,indicating that no obvious changes in astronauts'speed perception ability were found at the existing test time points and paradigms.However,the gravity internal model effect(difference between vertical downward and vertical upward)showed a trend of fading in the early stage of astronauts entering orbit.Conclusion Based on the computer screen TTC estimation paradigm,no significant changes in human speed perception ability were found during long-term spaceflight,but microgravity may weaken the human brain's gravity internal model.

The aim of this study was to qualitatively and quantitatively detect coronavirus(CoV)in the feces of bats from Qinghua Cave,Yunnan Province,China.CoV was qualitatively tested with reverse transcription polymerase chain reaction(RT-PCR),and homology and genetic evolution were analyzed with bioinformatics software.The established reverse transcription real-time fluores-cence quantitative PCR(qRT-PCR)method was applied to CoV quantification in bat feces.The positivity rate of CoV in 306 fecal samples collected from the fulvous fruit bat(Rousettus leschenaultia)was 7.8%(24/306)according to RT-PCR.All 24 strains of CoV belonged to β-CoV,and showed a similarity of 86.8%-100.0%at the nucleotide level and 95.2%-100.0%at the amino acid level,with respect to other β-CoV sequences in the NCBI database.The positivity rate of CoV was 18.6%(57/306)according to qRT-PCR,a value higher than that according to RT-PCR(χ2=25.3,P<0.05).The mean β-CoV load was 1.3×103 copies/μL.In conclusion,the bats in Qinghua Cave,Yunnan Province,carried CoV belonging to β-CoV.The established qRT-PCR method achieved good sensitiv-ity,accuracy,reproducibility,and a higher detection rate than that of RT-PCR,and can be used for rapid detection of β-CoV in bats.

Objective:To investigate effect of testosterone on polarization of M1 macrophages induced by lipopolysaccharide(LPS).Methods:CCK-8 method was used to detect effects of LPS and testosterone on RAW 264.7 cell viability.Morphological changes of cells were observed by optical microscope.mRNA expression levels of M1-type polarizing genes TNF-α,IL-1β and IL-6 in macro-phages were detected by qRT-PCR.Expression levels of M1-polarizing protein TNF-α and CD206 in macrophages were detected by immunofluorescence and Western blot.Secretion of inflammatory cytokines was detected by ELISA.Results:Testosterone could decrease mRNA expressions of TNF-α,IL-1β and IL-6 mRNA and protein expression of TNF-α.Finally,testosterone could decrease secretion of inflammation-related factors.Conclusion:Testosterone can inhibit LPS-induced transformation of macrophages to M1 polarization phenotype.

The aim of this study was to qualitatively and quantitatively detect coronavirus(CoV)in the feces of bats from Qinghua Cave,Yunnan Province,China.CoV was qualitatively tested with reverse transcription polymerase chain reaction(RT-PCR),and homology and genetic evolution were analyzed with bioinformatics software.The established reverse transcription real-time fluores-cence quantitative PCR(qRT-PCR)method was applied to CoV quantification in bat feces.The positivity rate of CoV in 306 fecal samples collected from the fulvous fruit bat(Rousettus leschenaultia)was 7.8%(24/306)according to RT-PCR.All 24 strains of CoV belonged to β-CoV,and showed a similarity of 86.8%-100.0%at the nucleotide level and 95.2%-100.0%at the amino acid level,with respect to other β-CoV sequences in the NCBI database.The positivity rate of CoV was 18.6%(57/306)according to qRT-PCR,a value higher than that according to RT-PCR(χ2=25.3,P<0.05).The mean β-CoV load was 1.3×103 copies/μL.In conclusion,the bats in Qinghua Cave,Yunnan Province,carried CoV belonging to β-CoV.The established qRT-PCR method achieved good sensitiv-ity,accuracy,reproducibility,and a higher detection rate than that of RT-PCR,and can be used for rapid detection of β-CoV in bats.

Objective:To investigate effect of testosterone on polarization of M1 macrophages induced by lipopolysaccharide(LPS).Methods:CCK-8 method was used to detect effects of LPS and testosterone on RAW 264.7 cell viability.Morphological changes of cells were observed by optical microscope.mRNA expression levels of M1-type polarizing genes TNF-α,IL-1β and IL-6 in macro-phages were detected by qRT-PCR.Expression levels of M1-polarizing protein TNF-α and CD206 in macrophages were detected by immunofluorescence and Western blot.Secretion of inflammatory cytokines was detected by ELISA.Results:Testosterone could decrease mRNA expressions of TNF-α,IL-1β and IL-6 mRNA and protein expression of TNF-α.Finally,testosterone could decrease secretion of inflammation-related factors.Conclusion:Testosterone can inhibit LPS-induced transformation of macrophages to M1 polarization phenotype.

Objective To evaluate the effectiveness of filter membranes made from different materials in monitoring the health status of rodents in barrier environment facilities by investigating their microbial capture performance.Methods Pasteurella pneumotropica(Pp)and Staphylococcus aureus(Sa)were used as representative strains to simulate the process of microbial capture by filter membranes under laboratory conditions.The microbial capture effectiveness of five self-selected filter membranes(M1,M2,M3,M4,and M5)with adsorption and breathability properties and a commercial filter membrane(T1)were comprehensively evaluated based on captured dust mass,minimum detection limit,and differences in Ct values obtained through fluorescence quantitative PCR detection.The best-performing self-selected filter membrane was placed in the ventilation ducts of cage racks within the barrier facility,with sentinel mice in corresponding cage racks as the control group.Staphylococcus epidermidis and Escherichia coli were used as indicator bacteria to calculate the positive detection rate and coincidence rate,thereby exploring the feasibility of using microbial capture filter membranes to monitor the health status of experimental animals in barrier facilities.Results In terms of the captured dust mass,the self-selected filter membrane M3(non-woven filter membrane with a diameter of 0.1 μm);showed a capture effectiveness second only to T1,with a capture mass of 0.126 g.For Sa,all filter membranes except M4 had a minimum detection limit of 102 CFU/g.For Pp,the minimum detection limit for all filter membranes was 102 CFU/g.However,the Ct value of the quantitative fluorescence PCR amplification results for M3 was significantly lower than that of other materials,indicating that M3 had the best capture performance among the five self-selected materials.In the filter detection verification experiment,the positive detection rate of Staphylococcus epidermidis in sentinel mouse feces and M3 was 50.00％(6/12)and 58.33％(7/12),respectively,with a coincidence rate of 92％.The positive detection rate of Escherichia coli in both sentinel mouse feces and M3 was 50.00％(6/12),with a coincidence rate of 100％.Conclusion Among the 5 self-selected filter membranes,M3 exhibits the best capturing performance.Within the barrier environment facilities,M3 outperforms sentinel mice in monitoring Staphylococcus epidermidis.Therefore,non-woven filter membrane with a diameter of 0.1 μm;can be used as the material for microbial capture filter membranes,providing valuable insights for the selection and application of microbial capture filter membranes used in PCR monitoring of cage exhaust air dust.

Objective To evaluate the role of autophagy in the treatment of neuropathic pain(NP)with hydrogen-rich saline.Methods Forty adult male Sprague-Dawley rats with successful intubation were randomly divided into 5 groups(n= 8)using a random number table:the sham operation group(group S),the neuropathic pain group(group C),the hydrogen-rich saline group(group H),the autophagy inhibitor group(group M)and the hydrogen-rich saline + autophagy inhibitor group(group HM).There were 8 rats in each group.The NP model was established by chronic constriction of the sciatic nerve(CCI)in rats.The autophagy inhibitor 3-methyladenine(3-MA)was intraperitoneally injected with 30μg/kg in the group M and the group HM.The hydrogen-rich saline(0.6 mmol/L)was intraperitoneally injected with 10 mL/kg in the group H and the group HM.The other groups were intraperitoneally injected with the same amount of normal saline twice a day for 7 consecutive days.Paw withdrawal threshold to mechanical stimulation(MWT)and paw withdrawal latency to thermal stimulation(TWL)were measured at 1 day before and 1,3,5,7 and 14 days after modeling(T0-T5).After the last measurement of pain threshold,the L4-L6 segment of spinal cord was removed for determination of the expression of autophagy-related proteins microtubule-associated protein light chain 3(LC3)Ⅱ,Beclin-1 and p62 proteins by Western blot assay.The expression levels of superoxide dismutase(SOD)and malondialdehyde(MDA)in spinal cord tissue were detected.Results Compared with the group S,MWT and TWL were decreased in the group C at T2-5,the expression levels of LC3 Ⅱ,Beclin-1 and p62 were increased,SOD activity was decreased,and MDA content was increased at T5(P＜0.05).Compared with the group C,MWT and TWL were increased in the group H at T2-5,LC3 Ⅱ and Beclin-1 protein expression levels were increased,p62 protein expression levels were decreased,SOD activity was increased,and MDA content was decreased at T5(P＜0.05).MWT and TWL were decreased in the group M at T2-5,LC3 Ⅱ and Beclin-1 protein expression levels were decreased,p62 protein expression levels were increased,SOD activity was decreased,and MDA content was increased at T5(P＜0.05).Compared with the group M,MWT and TWL were increased in the group HM at T2-5,LC3 Ⅱ and Beclin-1 protein expression levels were increased,p62 protein expression levels were decreased,SOD activity was increased,and MDA content was decreased at T5(P＜0.05).Conclusion Hydrogen-rich saline can alleviate neuropathic pain and inhibit oxidative stress in spinal cord in rats,and the mechanism may be related to the increase of autophagy.

Objective:To explore the role of activated CD4 + T cells in cardiac remodeling after myocardial infarction (MI). Methods:① Experiment in vitro: naive CD4 + T cells were isolated in mouse spleen, and then stimulated with plate-bound anti-CD3 and anti-CD28 for 48 hours. Exosomes isolated from the supernatant of activated CD4 + T cells were incubated with cardiac fibroblasts (CFs) for 48 hours, and then the ability of CFs proliferation, migration and differentiation were detected by cell counting kit-8 (CCK-8) assay, Transwell assay, and immunofluorescence assay. ② Experiment in vivo: 40 male C57 mice were divided into 4 groups according to random number table method, including control group (Ctrl group), sham operation group (Sham group), MI group, and exosome treatment group (MI+Exo group), with 10 in each group. The mice model of MI was established by ligating the left anterior descending coronary artery. In MI+Exo group, 40 μg/d exosomes were injected intravenously into the tail after modeling. Cardiac function and cardiac fibrosis post-MI were assessed by echocardiography and quantitative polymerase chain reaction (qPCR) at 4th week. Results:① In vitro: exosomes derived from activated CD4 + T cells significantly promote CFs proliferation, migration and differentiation [proliferation ability ( A value): 0.31±0.01 vs. 0.21±0.01, migration capability (cells/MP): 79.20±3.34 vs. 48.80±2.13, differentiation ability (α-smooth muscle actin, α-SMA; fluorescence intensity): 1.56±0.03 vs. 1.00±0.02, all P < 0.05]. ② In vivo: echocardiographic analysis showed that exosomes derived from activated CD4 + T cells aggravated the deterioration of cardiac dysfunction post-MI than MI group, as indicated by left ventricular ejection fraction (LVEF) and fractional shortening (FS) decreased significantly [LVEF: 0.185±0.008 vs. 0.257±0.022, FS: (9.72±1.72)% vs. (14.08±1.08)%, both P < 0.05], left ventricular end-diastolic diameter (LVEDD) and left ventricular end-systolic diameter (LVESD) increased significantly [LVEDD (mm): 5.43±0.29 vs. 4.62±0.35, LVESD (mm): 4.94±0.12 vs. 3.69±0.29, both P < 0.05]. Additionally, qPCR showed that exosomes derived from activated CD4 + T cells remarkably promoted myocardial fibrosis post-MI than MI group, as indicated by the mRNA expression of α-SMA, collagens (Col1a1, Col3a1) in MI+Exo group was significantly higher than that in MI group [α-SMA (2 -ΔΔCT): 4.72±0.89 vs. 3.58±0.78, Col1a1 (2 -ΔΔCT): 6.59±0.56 vs. 4.23±0.42, Col3a1 (2 -ΔΔCT): 13.40±1.03 vs.4.96±0.36, all P < 0.05]. Conclusion:Activated CD4 + T cells promote cardiac remodeling following MI through transferring exosomes to CFs.

Objective To analyze peripheral blood hemogram, lymphocyte micronucleus and chromosomal aberrations of radiologists, so as to provide basis for occupational protection and health monitoring of radiologists. Methods Lymphocyte micronucleus, chromosome and blood hemogram analysis were performed on 127 radiologists who received health examinations in 2015, 2017 and 2019, and they were assigned to the radiation group. In addition, 133 medical staff with no history of radiation exposure were selected as the control group. Results The micronucleus rate and chromosome aberration rate of the radiation group were higher than those of the control group, and the white blood cell and platelet counts were lower than those of the control group, both of which were statistically significant (P < 0.05). The total number of white blood cells in peripheral blood of 127 radiologists decreased gradually with the increase of exposure time to ionizing radiation, and the chromosome aberration rate increased gradually, all of which had statistical significance (P < 0.05). The rate of chromosomal aberration was higher in radiologists with damage work age of more than 20 years than in the low-work age group, and there was no statistical significance between different damage work age (P > 0.05). The chromosome aberration rate of nuclear medicine and interventional therapy was higher than that of other types, with statistical significance (P < 0.05). Conclusion Long-term exposure to low-dose ionizing radiation can reduce the total number of white blood cells and increase the chromosome aberration rate of radiologists. It is necessary to strengthen the protective measures for radiologists to reduce the degree of ionizing radiation damage, especially to strengthen the occupational protection for radiologists in nuclear medicine and interventional therapy.

Objective To evaluate the clinical value of adriamycin injection via the foramen ovale and around peripheral trigeminal branches under the guidance of X-ray for treatment of primary trigeminal neuralgia by comparison with the three-dimensional computed tomography (CT).Methods A total of 91 patients with primary trigeminal neuralgia of both sexes,aged 33-76 yr,with the course of disease 6 months-24 yr,with visual analogue scale score of 6-9,were divided into 2 groups using a random number table:X-ray group (n =43) and CT group (n =48).Hartel anterior approach was used to puncture the foramen ovale in 2 groups.One point five percent adriamycin 0.2,0.3 and 0.5 ml were injected via the supraorbital foramen,infraorbital foramen and oval foramen.When pain relief was poor (visual analogue scalc scorc≥ 4) within 1 yr after treatment,oxcarbazepine and adjuncts (tramadol,flupentixol and melitracen tablets,etc.) were taken orally.The requirement for oxcarbazepine and adjuncts was recorded during 1 day-1 week,1 week-1 month,1-3 months,3-6 months and 6 months-1 yr after treatment periods.The operation time,the nuinber of puncture,and developinent and recurrence of complications during treatment and within 1 yr after treatment were recorded.Results Compared with CT group,the number of puncture and incidence of facial hematoma during treatment were significantly increased (P ＜ 0.05 or 0.01),and no significant change was found in the operation time,requirement for oxcarbazepine and adjuncts,incidence of dizziness,nausea and vomiting during treatment,or the incidence and recurrence rate of masticatory muscle weakness and facial numbness after treatment in X-ray group (P＞0.05).Conclusion Compared with the three dimensional CT,X-ray provides similar efficacy and safety when used to guide adriamycin injection via the foramen ovale and around peripheral trigeminal branches for treatment of primary trigeminal neuralgia,showing that X-ray guidance has significant clinical value.