It has been demonstrated that long-term space flights have a significantly greater impact on the cardiovascular, skeletal, and nervous systems of astronauts. The structural and functional alterations in the skeletal and muscular systems resulting from exposure to weightlessness can lead to the development of low back pain, significantly impairing the ability of astronauts to perform tasks and respond to emergencies. Both space flight and simulated microgravity have been shown to result in low back pain among astronauts, with the following factors identified as primary contributors to this phenomenon. The occurrence of intervertebral disc (IVD) edema results in the stimulation of type IV mechanoreceptors, which subsequently activate nociceptive afferents. The protrusion of an IVD causes compression of the spinal nerve roots. Furthermore, the elongation of the vertebral column and/or the diminished lumbar curvature of the spine exert traction on the dorsal root nerves. Paravertebral muscle degeneration leads to the inhibition of decreased nociceptive activity of the wide-dynamic range neurons of the spinal dorsal horn. Moreover, endogenous pain descending facilitation triggered by conditioning stimulation can be enhanced via the thalamic mediodorsal nuclei, while endogenous pain descending inhibition triggered by conditioning stimulation can be weakened via the thalamic ventromedial nuclei. Psychological factors may contribute to the development of low back pain. The mechanisms governing the generation, maintenance, and alleviation of low back pain in weightlessness differ from those observed in normal gravitational environments. This presents a significant challenge for space medicine research. Therefore, the elucidation of the occurrence and development mechanism of low back pain in weightlessness is important for the prevention and treatment during space flight. To reduce the incidence of low back pain during long-term missions on the space station, astronauts may choose to wear specialized space clothing that can provide axial physiological loads, designed to stimulate both musculature and skeletal structures, mitigating potential increases in vertebral column length, diminished lumbar curvature, and intervertebral disc edema and/or muscular atrophy. Additionally, assuming a “fetal tuck position” described as the knees to chest position may increase lumbar IVD hydrostatic pressure, subsequently reducing disc volume, rectifying diminished lumbar curvature, and alleviating dorsal root nerve tensions. Moreover, this position may reduce type IV mechanoreceptor facilitation and nerve impulse propagation from the sinuvertebral nerves of the annulus fibrosus. Elongated posterior soft tissues (apophyseal joint capsules and ligaments) with spinal flexion may potentially stimulate type I and II mechanoreceptors. It is also recommended to exercise the paraspinal muscles to prevent and alleviate the decrease in their cross-sectional area and maintain their structure and function. Photobiomodulation has been proved to be an effective means of activating the pain descending inhibition pathway of the central nervous system. In addition, astronauts should be encouraged to participate in mission-related activities and strive to avoid psychological problems caused by the long-term confinement in a small space station. The article presents a concise review of potential causes and targeted treatment strategies for low back pain induced by space flight or simulated microgravity in recent years. Its objective is to further elucidate the mechanisms underlying the occurrence and development of low back pain in weightless environments while providing scientific evidence to inform the development of guidelines for preventing, treating, and rehabilitating low back pain during long-term space flights.

Five flavonoid glycosides were isolated from the methanol and ethyl acetate fractions of the ethanol extract of Diphylleia sinensi by using various chromatographic methods, including silica gel, MCI gel, Sephadex LH-20, ODS and semi-preparative HPLC. The structures of the isolated compounds were identified as diphyflavonoid A (1), diphyflavonoid B (2), quercetin-3-O-β-D-glucopyranoside (3), kaempferol-3-O-β-D-glucopyranoside (4), kaempferol-3-O-(6″-O-acetyl)-β-D-glucopyranoside (5) by spectroscopy methods (1D NMR, 2D NMR, UV, IR, and MS). Compounds 1 and 2 were two new flavonoid glycosides, and compounds 3 and 5 were isolated from the genus Diphylleia for the first time.

Acute cerebral infarction(ACI)has the characteristics of onset nasty and high mortality,and thus the rapid determination of the occurrence and development of ACI plays a key role in the diagnosis,treatment and prognosis of ACI patients.It has shown that the serum level of human haptoglobin(Hp)is related to ACI.In this study,surface enhanced Raman scattering(SERS)combined with immune recognition was applied to establish a quantitative analysis method for serum Hp.Firstly,the SERS substrate of silver nanoparticles was prepared on silicon wafer,and 4-mercaptobenzoic Acid(MBA)was used as a Raman probe by forming Ag—S bond and connecting it on the surface of nanoparticles.The carboxyl group of MBA was linked to amino group of self-made high-affinity antibody through forming CO—NH structure thus forming a SERS self-assembled chip of Hp(Ag/MBA/anti-Hp).Hp in serum could be specifically captured by antibodies on SERS substrate,which caused the shift of SERS characteristic peak of MBA.The results showed that there was a good linear relationship between the logarithm of Hp concentration and the SERS characteristic peak shift of MBA.The detection range was 1-1000 ng/mL(R2=0.988).The Hp concentrations in serum of 90 ACI patients were determined by this method,and the results were consistent with those of ELISA method,which proved the practicability and accuracy of this method.This method was highly specific,simple and convenient,which could realize the specific recognition and quantitative analysis of serum Hp,so as to be an effective means for clinical detection of serum Hp,thus providing a reference for the treatment and prognosis of ACI.

Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannan-binding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP. Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays. Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05). Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.

Objective In this study,we analyzed the transcriptome sequences of Kupffer cells exposed to simulated microgravity for 3 d and conducted biological experiments to determine how microgravity initiates apoptosis in Kupffer cells. Methods Rotary cell culture system was used to construct a simulated microgravity model.GO and KEGG analyses were conducted using the DAVID database.GSEA was performed using the R language.The STRING database was used to conduct PPI analysis.qPCR was used to measure the IL1B,TNFA,CASP3,CASP9,and BCL2L11 mRNA expressions.Western Blotting was performed to detect the level of proteins CASP3 and CASP 9.Flow cytometry was used to detect apoptosis and mitochondrial membrane cells.Transmission electron microscopy was used to detect changes in the ultrastructure of Kupffer cells. Results Transcriptome Sequencing indicated that simulated microgravity affected apoptosis and the inflammatory state of Kupffer cells.Simulated microgravity improved the CASP3,CASP9,and BCL2L11 expressions in Kupffer cells.Annexin-V/PI and JC-1 assays showed that simulated microgravity promoted apoptosis in Kupffer cells.Simulated microgravity causes M1 polarization in Kupffer cells. Conclusion Our study found that simulated microgravity facilitated the apoptosis of Kupffer cells through the mitochondrial pathway and activated Kupffer cells into M1 polarization,which can secrete TNFA to promote apoptosis.

Objective:To investigate the prospective association of sleep duration with the development of chronic obstructive pulmonary disease (COPD) in adults in Suzhou.Methods:The study used the data of 53 269 participants aged 30-79 years recruited in the baseline survey from 2004 to 2008 and the follow-up until December 31, 2017 of China Kadoorie Biobank (CKB) conducted in Wuzhong District, Suzhou. After excluding participants with airflow limitation, self-reported chronic bronchitis/emphysema/coronary heart disease history at the baseline survey and abnormal or incomplete data, a total of 45 336 participants were included in the final analysis. The association between daily sleep duration and the risk for developing COPD was analyzed by using a Cox proportional hazard regression model, and the hazard ratio ( HR) values and their 95% CI were calculated. The analysis was stratified by age, gender and lifestyle factors, and cross-analysis was conducted according to smoking status and daily sleep duration. Results:The median follow-up time was 11.12 years, with a total of 515 COPD diagnoses in the follow-up. After adjusting for potential confounders, multifactorial Cox proportional hazard regression analysis showed that daily sleep duration ≥10 hours was associated with higher risk for developing COPD ( HR=1.42, 95% CI: 1.03-1.97). The cross analysis showed that excessive daily sleep duration increased the risk for COPD in smokers ( HR=2.49, 95% CI: 1.35-4.59, interaction P<0.001). Conclusion:Longer daily sleep duration (≥10 hours) might increase the risk for COPD in adults in Suzhou, especially in smokers.

Objective:To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications.Methods:This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression.Results:The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion:Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.

Objective To analyze the cognition level of health care workers(HCWs)and the management status of various levels of medical institutions towards allergy reactions to commonly used antimicrobial agents.Methods HCWs and clinical pharmacists who were related to the diagnosis and treatment of antimicrobial agents in 14 medical institutions of city-level and autonomous prefectures in Gansu Province were randomly selected for a questionnaire survey.The survey contents included respondents'basic information,criteria for judging antimicrobial allergy,awareness on procedures related to antimicrobial allergy,and antimicrobial management level of different levels of medical institutions.Results A total of 8 670 valid questionnaires from HCWs were collected,including 3 300 phy-sicians,5 024 nurses and 328 pharmacists.160,775,2 123 and 5 612 HCWs were with senior,associate,interme-diate and junior professional titles,respectively.87.66％of the HCWs received relevant training on antimicrobial management in the past two years,the proportion of HCWs from different levels of medical institutions who have received training on antimicrobial management in the past two years was statistically significant different(x2=42.668,P＜0.001).HCWs with senior professional titles had the highest proportion of receiving relevant training(93.75％),there was a statistically significant difference in the proportion of receiving antimicrobial management training among HCWs with different professional titles in the past two years(x2=69.782,P＜0.001).50.98％of HCWs were not clear about penicillin allergy,and most of whom were with junior professional titles,accounting for 68.52％.25.19％of HCWs expressed uncertainty about whether patients with penicillin allergy could use cephalosporins,225 of whom were with associate professional titles,accounting for 29.03％of the total number of HCWs with associate profe-ssional titles.6.11％of HCWs had no experience in skin test procedure;46.94％of HCWs expressed that their medical institutions had no or unclear about whether their medical institutions had an antimicrobial allergy assess-ment team.Conclusion HCWs'judgment on allergy reactions to commonly used antimicrobial agents and aware-ness on antimicrobial application is not high enough,and the overall management level of antimicrobial allergy in all levels of medical institutions is poor.The popularity of antimicrobial allergy assessment teams is not high,and there is an urgent need to strengthen supervision,management,training,et al.

Objective To analyze the incidence and risk factors of hypothermia in elderly patients with malnutrition during proximal femoral nail antirotation(PFNA)internal fixation under general anesthesia.Methods A total of 139 elderly patients underwent PFNA internal fixation under general anesthesia were selected,and the nutritional status scores 1 day before surgery ranged from 0 to 11 points.Univariate and multivariate Logistic binary regression analysis was performed to analyze the related factors that may lead to intraoperative hypothermia.Results Among 139 elderly patients with preoperative nutritional scores of 0 to 11 points,79 cases(56.83%)developed intraoperative hypothermia.The results of univariate and multivariate Logistic binary regression analysis suggested that age≥75 years old,mini nutritional assessment short form(MNA-SF)nutritional score 0 to 7 points,BMI<18.5 kg/m2,duration of general anesthesia≥2 hours,intraoperative flushing fluid volume≥1 000 mL and intraoperative fluid volume≥1 000 mL were the risk factors for the occurrence of intraoperative hypothermia in elderly patients(OR>1,P<0.05).The use of warm blanket insulation was the protective factor against the occurrence of intraoperative hypothermia(OR<1,P<0.05).Conclusion The incidence of intraoperative hypothermia during PFNA internal fixation under general anesthesia in elderly patients with mainutrition before operation is high,and patients with poor nutritional status are more likely to develop intraoperative hypothermia.Patients with older age,poor nutritional status,lower BMI,longer duration of general anesthesia,and more intraoperative flushing fluid volume and intraoperative fluid volume are likely to lead to intraoperative hypothermia.The use of warm blanket can reduce the incidence of intraoperative hypothermia.

Objective To explore the value of ultrasonic quantitative measurement of hepatorenal index(HRI)for diagnosing non-alcoholic fatty liver disease(NAFLD)in children.Methods Abdominal ultrasound and upper abdominal MRI data of 70 obese children were retrospectively analyzed.ROI with different sizes and shapes of liver and right kidney were delineated on longitudinal and transverse ultrasound images,respectively,and the echo intensity of ROIs were measured to obtain HRIsmall ROI on longitudinal section,HRIsmall ROI on transverse section,HRIlarge ROI on longitudinal section and HRIlarge ROI on transverse section,i.e.HRI1,HRI2,HRI3,HRI4,while the gray,skewness and kurtosis of liver ultrasound image were recorded.Liver proton density fat fraction(PDFF)were measured based on MRI,and NAFLD was diagnoses taken PDFF≥6%as standard.The correlations of HRI with PDFF and liver ultrasound image related parameters were analyzed.Taken MRI as the standard,receiver operating characteristic(ROC)curve was drawn to evaluate the diagnostic efficacy of HRI for NAFLD.Multivariate logistic regression analysis was performed taken age,sex,body mass index(BMI)percentile,HRI3 and liver ultrasound image related parameters as independent variables and MRI diagnosis of NAFLD as dependent variable to screen the predictors of MRI diagnosis of NAFLD.Results HRI1,HRI2,HRI3 and HRI4 obtained with ultrasound was 1.89±0.52,1.88±0.55,1.97±0.51 and 1.92±0.55,respectively.PDFF obtained with MRI was(12.53±3.14)%,and diagnosed NAFLD in 34 cases.HRI and PDFF had moderate positive correlation(r=0.51-0.61,all P＜0.01).The correlation between HRI3 and PDFF was the strongest(r=0.61),and HRI3 was weakly correlated with liver gray3(r=-0.270,P=0.020),with area under the curve(AUC)for diagnosing NAFLD of 0.93(P＜0.01).BMI percentile(OR=1.06),HRI3(OR=34.20)and liver gray3(OR=0.79)were all predictive factors for MRI diagnosis of NAFLD.Conclusion Ultrasonic quantitative measurement of HRI had high clinical value for diagnosing NAFLD in children.