Objective To study on quenching free radical substances in antarctic ice alga.Methods Antarctic ice alga Berkeleya rutilans H-15 used as material,complete experiment of preparation free radical scavenging substances was established.All of these include the extraction of active substances by methanol,then pursuing and determination of the separation effect and change of active substances by DPPH and Godin method;the primary separation and purification by silica gel 60 column chromatogram;the farther purification by Sephadex LH column chromatogram and the purity determination of compound by HPLC.The type of compound and functional group of high pure compound were determined by the IR spectrum,HPLC-MS.Results One pure compound with strong activity was obtained from Berkeleya rutilans H-15,and it was confirmed to belong to phenol derives by analysis of IR spectrum and HPLC-MS.Conclusion It was completely feasible to find and acquire quenching free radical substances in antarctic ice alga,which initiated a new way to obtain natural antioxidant active substances from antarctic microorganism.

Objective To study on bioactive chemical compounds against ultraviolet irradiation in antarctic ice microalgae.Methods Four kinds of Antarctic ice microalgae were cultured under the conditions of low temperature,illumination,UV-A and UV-B irradiation.The chemical compounds were extracted by methanol and analyzed by spectrophotometer and HPLC/MS.The molecular structures were elucidated according to these data.The chemical compounds were irradated by sunshine to observe the speed of degradation and to estimate the bioactivity.Results There were five active compounds in Chlorophyceae L-4 and 7 active compounds in Diatom HF-9,in which 6 compounds belong to MAAs(mycosporine-like amino acids) and were of more bioactivity against ultraviolet irradiation.Conclusion MAAs from of Antarctic ice microalgae play an important role in resisting ultraviolet irradiation.

Objective To study the accuracy,clinical value and limit in assessing the vessels surrounding pancreas involved by pancneutic carcinoma with low field MRI.Methods MRI scanning was performed in 55 patients with pancreatic carcinoma.We prospectively evaluated the MRI findings of vascular involvement by pancreatic carcinoma,and compared with the surgical results.Results Of total 55 cases,50(91%)cases were correctly diagnosed on MRI .MRI carries an accuracy of 86% for prediction of resectility,and accuracy of 93% for unresectility.Conclusion Low field MRI can accurately assess the peripancreative vessels ,but it has limited value in the patients with pancreatic carinomaⅠa orⅠb.

Objective To evaluate the value of 1.5T MRI in differential diagnosis of circular enhanced brain lesions.Methods A total of 120 patients,admitted to our hospital from April 2009 to March 2013 and confirmed by clinical pathology,including 40 of brain metastasis,40 of astrocytoma and 40 of brain abscess,were chosen in our study; The characteristic signs of MRI findings of these patients were retrospectively analyzed.Results There were significant differences in the location,number,size,morphology,ring structure,multiple mural nodules,and smooth outside wall of the lesions between patients with brain metastasis and astrocytoma.There were significant differences in the number,size,ring structure,ring wall thickness,and smooth outside wall of the lesions,T2-weighted imaging (T2WI) low signal ring sign,hydraulic fluid level sign,lesion center diffusion weighted imaging (DWI) hyperintensity and apparent diffusion coefficient (ADC) map low signal between patients with brain metastasis and abscess.There were significant differences in the location,shape and multi locular lesions between patients with astrocytoma and abscess.The signs indicating brain metastasis included multi lesions,grade Ⅲ peripheral edema,small lesions,lesions located at the juncture of gray and white matter,with displaying percentages of 79.5％,70.3％,67.5％,48.5％ and 47.9％.The signs indicating astrocytoma included multi locular lesion,lesions located at the white matter,multi mural nodule,rough outside wall and irregular in shape,with displaying percentages of 85.7％,78.0 ％,77.8％,65.4 ％ and 51.9％.The signs indicating abscess included daughter ring sign,DWI hyperintensity and ADC map low signal,circular wall notch sign,hype-intensity rim on T2WI and fluid-fluid level,with displaying percentages of 100％,100％,100％,92.6％ and 82.4％.Conclusion The 1.5T MRI can displaythe characteristic signs of brain metastases,gliomas and brain abscess,which enjoys high value in differential diagnosis.

Objective To access the value of three dimensional gradient echo two-point Dixon water-fat separation sequence (3 D-DIXON) in quantitative diagnosis of non-alcoholic fatty liver disease(NAFLD) by comparing with in-phase/opposed-phase (IN/OPP)and proton magnetic resonance spectroscopy (1 H-MRS).Methods A total of 69 patients with NAFLD diagnosed by CT were divided into two groups by the ratio of liver spleen in CT (group A,low-grade fatty liver,n=32;group B,moderate and severe fatty liver,n=37).All patients underwent MR 3D-DIXION,1H MRS and IN/OPP examination twice within 1 week after CT examination.Fat fraction(FF) was evaluated and analyzed respectively.Results Pearson linear correlation analysis showed significant positive correlation between group A and group B about FF3D-DIXON,FFMRs and FFIN/OPP.Area under ROC curve (AUC) was different:AUCsYNTHESIZE＞AUCMRs＞AUCIN/OPP＞AUC3D-DIXON.Kruskal-Wallis H revealed significant difference among the three sequences no matter in group A or group B (P＜0.05).FF values of the three sequences (FF3D-DIXON,FFMRs and FFIN/OPP) were negatively correlated with CT liver/ spleen ratio in each group.The cut-off value of 3D-DIXON,IN/OPP and 1 H-MRS to diagnose presence or absence of fatty liver was 4.9 3 9 ％,5.2 8 4 ％ and 10.4 6 0 ％.Conclusion FF values measured by MRI methods might significantly vary based on different sequences.1 H-MRS is also the main method for quantitative assessment of fatty liver,3D-DIXON showed significant advantage in quantifying moderate and severe fatty liver.

Objective To observe the value of augmented reality(AR)navigation system for assisting CT-guided puncture of pulmonary nodules in dog models.Methods Five healthy dogs were selected,and 4 target lung rings were implanted in each dog to build pulmonary nodule models.Deferring to crossover design,CT-guided punctures were performed with or without AR navigation 2 and 4 weeks after successful modeling,respectively,while punctures with AR navigation were regarded as AR group and the others as conventional group,respectively.The time duration of puncturing,the times of CT scanning,of needle adjustment,and the deviation distance between needle pinpoint to the center of pulmonary nodule shown on three-dimensional reconstruction were compared between groups.Results The duration time of puncture in AR group and conventional group was(13.62±5.11)min and(20.16±4.76)min,respectively.In AR group,the times of CT scanning,of needle adjustment,and the deviation distance was 2.40±0.50,2.75±0.44 and(2.94±1.92)mm,respectively,while in conventional group was 3.10±0.64,3.70±0.57 and(4.90±3.38)mm,respectively.The introduction of AR navigation was helpful to shortening the duration of puncture,reducing times of CT scanning and needle adjustment,also decreasing positioning error of needle pinpoint(all P＜0.05).In contrast,the variance of puncture sequences and dogs had no obvious effect on the results(both P＞0.05).Conclusion AR navigation system could improve accuracy and efficiency in CT-guided puncture of pulmonary nodules in dog models.

【Objective】 To explore the difference of demographics and influencing factors of motivations between whole blood donors and plasmapheresis donors, so as to provide scientific reference for effective recruitment strategy. 【Methods】 A total of 200 whole blood donors from Guangyuan Blood Center and 200 plasmapheresis donors from Jiange Plasmapheresis Station were selected in August 2021 for on-site questionnaire survey using the method of cross-sectional survey. Statistical analysis was performed by chi-square test, univariate and multivariate logistic regression. 【Results】 There were significant differences in gender, age, occupation, education level and annual family income between whole blood donors and plasmapheresis donors (P<0.05). Males accounted for a large proportion of whole blood donors(124/196, 63.3%), whereas females accounted for a large proportion of plasmapheresis donors(117/198, 59.1%). There was little difference in the number of whole blood donors in different age groups, while the age of plasmapheresis donors was concentrated in 40~59 years old (167/198, 84.3%). In terms of occupation, civil servants (including public institutions) accounted the highest proportion in whole blood donors (41/196, 20.9%), and farmers accounted the highest proportion (152/198, 76.8%) in plasmapheresis donors. The number of whole blood donors increased with the education level, and donors with college/university and above degree accounted the largest proportion (80/196, 40.8%). Plasmapheresis donors with junior middle school education and college/university and above accounted the largest and smallest proportion (49.5% vs 4.5%). The annual family income of whole blood donors ranged from 30 000 to 80 000 yuan accounted the largest proportion (109/196, 55.6%), and the annual family income of plasmapheresis donors less than 30 000 yuan accounted the largest proportion (132/198, 66.7%). 【Conclusion】 There were significant statistical differences in gender, age, education level, occupation and annual family income between whole blood and plasmapheresis donors. Therefore, targeted recruitment strategies should be formulated.

【Objective】 To analyze the characteristics and mobility of the overlapping population of voluntary blood donation and plasmapheresis donation, so as to provide a scientific basis for the formulation of recruitment and retention strategies for blood donation and plasmapheresis donation, and to further propose a scientific reference for the decision-making of blood banks and plasmapheresis station management in China. 【Methods】 The basic information of blood donors and plasmapheresis donors in two counties in Guangyuan, Sichuan Province, which carried out whole blood collection and plasmapheresis collection from the establishment of the station to July 31, 2021 was statistically compared and analzed using the chi-square test and Post hoc testing test. 【Results】 As of July 31, 2021, a total of 50 658 people participated in blood donation and 63 375 people participated in plasmapheresis donation in Jiange County and Cangxi County, with a total overlap of 6 189 people. In the two regions, 16 458 (35.2%) people aged 40 to 50, and 35 558 people (56.1%) were over 50 years old. Among the overlapping population, 2 496 (40.3%) were 40 to 50 years old, accounted for the largest proportion, and 3 146 (50.8%) were males. Significant differences were noticed in age (P<0.001) and gender (P<0.001). There was a shift in dontion in 5 183, including 2 072 people from plasma to blood and 3 111 people from blood to plasma, among which 2 671 (51.5%) were men and 3 632 (70.1%) were over 50 years old, with significant differences in gender (P<0.05) and age (P<0.001). 【Conclusion】 There were a small number of donors donating both blood and plasma in Jiange and Cangxi, and men aged 40 to 50 were the majority, and people over 50 years old were more likely to shift the donation goals. The vast majority of donors have a single and fixed donation goal (blood or plasma), and are not easy to change.

【Objective】 To analyze the dynamic relationship between the setting up of plasmapheresis station and the volume of voluntary blood donation collected using panel vector autoregressive model, so as to provide scientific reference for the management policies of blood stations and plasmapheresis stations in China. 【Methods】 The data collected from blood stations in seven administrative regions of Guangyuan, Sichuan Province from 2011 to 2021, as well as plasma collection data from two plasmapheresis stations in the region within two years since their operation, were collected. A panel vector autoregressive model was constructed. Impulse response analysis and variance decomposition analysis were used to analyze the impact and time lag effects of simulated plasmapheresis station settings on the collection volume of voluntary blood donation. Covariance analysis was used to explore whether the establishment of plasmapheresis station had an impact on the volume of voluntary blood donation collected after excluding the impact of initial value differences. 【Results】 The pulse response results showed that after the plasmapheresis station was set up, there was a negative impact effect on the voluntary blood donation collection volume at the first stage, and its impact began to rise after the second stage, reached the highest value in the third stage, and then began to decline. After the seventh stage, it tended to be stable. However, within the 10 stage range, the confidence interval for the response strength of voluntary blood donation collection volume always included 0, indicating that the response of blood collection volume to the plasmapheresis station setting in the region was not statistically significant. The results of variance decomposition showed that the contribution of collection volume of voluntary blood donation to their own impact reached 94.3%. In terms of the contribution of plasmapheresis station factors, the number of plasma donors has a relatively greater impact on the volume of voluntary blood donation collected(2.2%). Covariance analysis showed that after removing the initial confounding factors, whether to establish a plasmapheresis station had no significant impact on blood donation volume in the two groups of regions (P>0.05). 【Conclusion】 The establishment of a new plasmapheresis station will have a certain impact on blood collection volume of blood stations in the region in a short term, but in the long term, it may not directly affect the voluntary blood donation collection in the region.

BACKGROUND: Currently, the effect of the 2022 nationwide coronavirus disease 2019 (COVID-19) wave on the perioperative prognosis of surgical patients in China is unclear. Thus, we aimed to explore its influence on postoperative morbidity and mortality in surgical patients. METHODS: An ambispective cohort study was conducted at Xijing Hospital, China. We collected 10-day time-series data from December 29 until January 7 for the 2018-2022 period. The primary outcome was major postoperative complications (Clavien-Dindo class III-V). The association between COVID-19 exposure and postoperative prognosis was explored by comparing consecutive 5-year data at the population level and by comparing patients with and without COVID-19 exposure at the patient level. RESULTS: The entire cohort consisted of 3350 patients (age: 48.5 ± 19.2 years), including 1759 females (52.5%). Overall, 961 (28.7%) underwent emergency surgery, and 553 (16.5%) had COVID-19 exposure (from the 2022 cohort). At the population level, major postoperative complications occurred in 5.9% (42/707), 5.7% (53/935), 5.1% (46/901), 9.4% (11/117), and 22.0% (152/690) patients in the 2018-2022 cohorts, respectively. After adjusting for potential confounding factors, the 2022 cohort (80% patients with COVID-19 history) had a significantly higher postoperative major complication risk than did the 2018 cohort (adjusted risk difference [aRD], 14.9% (95% confidence interval [CI], 11.5-18.4%); adjusted odds ratio [aOR], 8.19 (95% CI, 5.24-12.81)). At the patient level, the incidence of major postoperative complications was significantly greater in patients with (24.6%, 136/553) than that in patients without COVID-19 history (6.0% [168/2797]; aRD, 17.8% [95% CI, 13.6-22.1%]; aOR, 7.89 [95% CI, 5.76-10.83]). Secondary outcomes of postoperative pulmonary complications were consistent with primary findings. These findings were verified through sensitivity analyses using time-series data projections and propensity score matching. CONCLUSION: Based on a single-center observation, patients with recent COVID-19 exposure were likely to have a high incidence of major postoperative complications. REGISTRATION NCT05677815 at https://clinicaltrials.gov/ .
Female ; Humans ; Adult ; Middle Aged ; Aged ; Cohort Studies ; COVID-19/complications* ; Pandemics ; Retrospective Studies ; Postoperative Complications/epidemiology*