ObjectiveTo assess the microstructural involvement of gray matter in recovered COVID-19 patients using Synthetic MRI. MethodsThis study was conducted in 29 recovered COVID-19 patients， including severe group （SG， n=11） and ordinary group （OG， n=18）. Healthy volunteers matched by age， sex， BMI and years of education were selected as a healthy control group （HC=23 cases）. Each subject underwent synthetic MRI to generate quantitative T₁ and T₂ maps， and the T₁ and T₂ maps were segmented into 90 regions of interest （ROIs） using automatic anatomical labeling （AAL） mapping. T₁ and T₂ values for each ROI were obtained by averaging all voxels within the ROIs. The T₁ and T₂ values of the 90 brain regions between the three groups were compared. ResultsRelative to HC， the SG had significantly higher T2 values in bilateral orbital superior frontal gyrus， bilateral parahippocampal gyrus， bilateral putamen， bilateral middle temporal gyrus， bilateral Inferior temporal gyrus， left orbital superior frontal gyrus， left orbital inferior frontal gyrus， left gyrus rectus， left anterior cingulate and paracingulate gyri， right median cingulate and paracingulate gyri， left posterior cingulate gyrus， and left supramarginal gyrus （P＜0.05）； Relative to OG， SG showed significantly increased T₂ values in the left rectus gyrus， left parahippocampal gyrus， bilateral middle temporal gyrus， and bilateral inferior temporal gyrus （P＜0.05）. Relative to HC， the T₁ values of SG were significantly increased in bilateral orbital superior frontal gyrus， left rectus gyrus， left anterior cingulate and paracingulate gyri， right posterior cingulate gyrus， left parahippocampal gyrus， left lingual gyrus， left putamen， left thalamus（P＜0.05）； Relative to OG， the T₁ values of SG were significantly higher in the right posterior cingulate gyrus， right calcarine fissure and surrounding cortex， and left putamen （P＜0.05）. ConclusionsEven after recovering from COVID-19， patients may still have persistent or delayed damage to their brain gray matter structure， which is correlated with the severity of the condition. SyMRI can serve as a sensitive tool to assess the extent of microstructural damage to the central nervous system， aiding in early diagnosis of the disease.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objective To evaluate the effect of preoperative pulmonary artery pressure on perioperative prognosis of the recipients with end-stage heart failure undergoing heart transplantation. Methods Clinical data of 105 recipients receiving heart transplantation were retrospectively analyzed. The mean pulmonary artery pressure (mPAP) was used as the diagnostic criterion. The optimal cut-off value of mPAP for predicting perioperative prognosis of heart transplant recipients was determined. According to the optimal cut-off value of mPAP, all recipients were divided into the low mPAP group (n=66) and high mPAP group (n=39). Intraoperative indexes (cardiopulmonary bypass time, aortic occlusion time, assisted circulation time and cold ischemia time of donor heart) and postoperative indexes [intra-aortic balloon pump (IABP) support rate, IABP support time, extracorporeal membrane oxygenation (ECMO) support rate, ECMO support time, mechanical ventilation time, length of ICU stay, incidence of moderate and severe tricuspid regurgitation and perioperative mortality rate] were compared between the low and high mPAP groups. The prognosis of the two groups was compared. Results The optimal cut-off value of mPAP in predicting clinical prognosis of heart transplant recipients was 30.5 mmHg. In the high mPAP group, the ECMO support rate and perioperative mortality rate were higher than those in the low mPAP group (both P < 0.05). No significant differences were observed in the cardiopulmonary bypass time, aortic occlusion time, assisted circulation time, cold ischemia time of donor heart, IABP support rate, IABP support time, ECMO support time, mechanical ventilation time, length of ICU stay and incidence of moderate and severe tricuspid regurgitation between two groups (all P > 0.05). No significant differences were noted in the 1-, 2-, 3- and 4- survival rates between two groups (all P > 0.05). Conclusions Preoperative mPAP in patients with end-stage heart failure is intimately correlated with perioperative prognosis of heart transplant recipients. The optimal cut-off value of mPAP in predicting perioperative prognosis of heart transplant recipients is 30.5 mmHg. In the high mPAP group, perioperative ECMO support rate and perioperative mortality rate are high, which do not affect the medium and long-term prognosis of the recipients undergoing heart transplantation.

Multi-leaf collimators are devices to block rays from medical linear accelerators, which directly affect doses to targets and organs at risk by adjusting field shape and dose distribution in radiation therapy. As multi-leaf collimators are diversified in structure, there has been growing research on dosimetric comparison of various multi-leaf collimators. In this paper, we introduced the classifications of multi-leaf collimators according to their basic components, as well as the hardware structure and design features of the products of main accelerator manufacturers, including Varian’s Millennium MLC, HD120 MLC, and Halcyon, Elekta’s MLCi/i2 and Agility, and Accuray’s InCise 2 MLC and TomoTherapy. In terms of clinical application evaluation, focusing on radiotherapy plans for nasopharyngeal carcinoma, we reviewed comparative studies on the dosimetry performance of multi-leaf collimators and the effects of relevant parameters on dose distribution. We hope this review on the design and application evaluation of multi-leaf collimators can provide a reference for more innovative design and accelerator selection and parameter setting in clinical individualized treatment.

Objective    To analyze the surgical efficacy and influencing factors of myasthenia gravis (MG) patients with thymic atrophy after thymectomy. Methods    The clinical data of MG patients with thymic atrophy undergoing thymectomy between October 2014 and May 2018 in Daping Hospital of Army Medical University and Shijiazhuang People Hospital were retrospectively analyzed. Results    A total of 71 patients were collected, including 40 males and 31 females with a mean age of 45.17±12.42 years. All patients received the surgery successfully. After the surgery, 20 (28.17%) patients were stable remission, 12 (16.90%) patients were minimal manifestation status,19 (26.76%) patients were improved, 5 (7.04%) patients showed no change, 3 (4.23%) patients were worsened, 10 (14.08%) patients were exacerbated and 2 (2.82%) patients were dead. Multivariate logistic regression analysis showed that the preoperative illness duration (OR=4.61, 95%CI 1.13-18.85, P=0.03), and postoperative pyridostigmine combined with immunosuppressive (OR=0.12, 95%CI 0.03-0.45, P=0.00) were independent risk factors for long-term efficacy of thymectomy for MG patients with thymic atrophy. Conclusion    Early surgery after diagnosis of MG and postoperative pyridostigmine combined with immunosuppressive treatment is beneficial to the prognosis of MG patients with thymic atrophy.

Objective To apply the personal digital assistant(PDA)scanning positioning two-dimensional code recognition technology in writing nursing records in patients with acute ischemic stroke treated with intravenous thrombolysis,and to evaluate the application effect.Methods The quasi-experimental design was conducted.The nursing records routinely written by emergency nurses using mobile nursing cart for 58 patients with acute ischemic stroke treated with intravenous thrombolysis admitted to department of emergency of Zhejiang Hospital from September 2021 to February 2022 was taken as the control group,and the nursing records written by emergency nurses using PDA for 51 patients with acute ischemic stroke treated with intravenous thrombolysis from March 2022 to August 2022 through scanning positioning two-dimensional code recognition technology was used as the observation group.The differences of time required for writing nursing records and the incidence of errors in nursing records were compared between the two groups,and the satisfaction of emergency nurses in the observation group using PDA scanning positioning two-dimensional code to write nursing records was evaluated.Results The time required for writing nursing records in the observation group was significantly shorter than that in the control group[seconds:137(109,192)vs.480(436,604),P<0.05],the incidence of inadequate records of the first course of specialist assessment[3.92％(2/51)vs.20.69％(12/58)],and the incidence of insufficiently detailed records of thrombolytic observations[7.84％(4/51)vs.43.10％(25/58)]were significantly lower than the control group(both P<0.05).The differences between the observation group and the control group were not statistically significant when comparing the incidence of irregularities in thrombolytic drug pump records[0％(0/51)vs.1.72％(1/58)],incidence of irregularities in muscle strength assessment records[1.96％(1/51)vs.5.17％(3/58)],and the occurrence of typos in the nursing records[0％(0/51)vs.3.44％(2/58),all P>0.05].In addition,the overall satisfaction of emergency nurses in the observation group using PDA scanning positioning two-dimensional code to write nursing records was 92.94％(2 844/3 060),and the average score of each item in the synchronous nursing record of the positioning two-dimensional code was>4.5 points,among which the satisfaction score of ease of operation was(4.78±0.50),the acceptance of emergency nurses using PDA scanning positioning two-dimensional code to write nursing records was good,and could meet the clinical needs.Conclusion Using PDA scanning positioning two-dimensional code assists the writing of nursing records in the stroke treatment process,shortens the time required for writing nursing records of emergency nurses,reduces the incidence of errors in nursing records,and improves the quality of nursing records;At the same time,for emergency nurses,it can effectively reduce the burden of writing nursing records and improve their satisfaction with nursing records,which is worthy of clinical promotion.

Objective:To describe the baseline characteristics of the subjects enrolled in the China Quantitative CT (QCT) big data program in 2018—2019.Methods:Based on baseline data from the Chinese health big data project from January 2018 to December 2019 from the eligible enrolled population, measurements of bone mineral density (BMD) and visceral adipose tissue (VAT) were performed using Mindways′ QCT Pro Model 4 system. The baseline data of age, gender, regional distribution, height, weight, abdominal circumference, blood pressure, blood routine and blood biochemical tests were analyzed. And the single factor analysis of variance (ANOVA) was used to check the age related trend of BMD and VAT in both genders.Results:After screening the inclusion exclusion criteria and outliers of the main indicators, 86 113 people were enrolled in the project. The enrollment rate was 92.47%, including 35 431 (41.1%) women and 50 682 (58.9%) men, and the ratio of men to women was 1.43. The mean age was (50.3±12.7) years in all the subjects, and it was (50.2±12.8) years and (50.4±12.5) years in men and women, respectively, and there was no statistical difference between the two genders ( P>0.05). Total of 43 833 people were enrolled in east China, it was the largest group by region (50.90%), it was followed by central China (16 434 people, 19.08%), and the number of people enrolled in Northeast China was the lowest (2 914 people, 3.38%). The rate of completing of health information indicators related to the main outcome of the study were all above 70%, and there were significant differences between men and women (all P<0.05). The mean BMD was (139.33±46.76) mg/cm 3 in women, (135.90±36.48) mg/cm 3 in men, which showed a decreasing trend with age in both gender (both P<0.001); the mean intra-abdominal fat area was (116.39±56.23) cm 2 in women, (191.67±77.07) cm 2 in men, and there was an increasing trend with age in both men and women (both P<0.001). Conclusions:There are gender differences in BMD and VAT measured by QCT with different age tendency, and there are gender differences in health information index. Regional factors should also be taken into account for regional differences in the inclusion of data.

Objective:To investigate the normal reference values of spinal bone mineral density measured by quantitative computed tomography (QCT) and the differences of bone mineral density (BMD) in different regions of in Chinese adult males.Methods:Men who underwent low-dose CT lung scan for cancer screening in regions of Northeast, North, East, South, Central and Southwest of China from January 2018 to December 2019 were selected. And the lumbar vertebrae BMD values in the male subjects were measured by the QCT system (Mindways Software, Inc.). The mean BMD values and their decline rates were calculated at an age interval of 10 years, and the prevalence of osteoporosis was calculated according to the American College of Radiology spine QCT osteoporosis diagnostic criteria.Results:A total of 50 682 males with a mean age of (50.22±12.79) years (ranged 20 to 98 years) were included in this study. The peak BMD of (173.11±28.56) mg/cm 3 in the healthy Chinese adult male population appeared in the age group of 20 to 29 years and then declined with age. Before the age of 70 years, the BMD was relatively higher in males in South China, and it was lower in Central China and Southwest China, and it was intermediate in Northeast, North and East of China, with statistically significant differences. There was no significant differences in BMD in the males in the two age groups of 70 to 79 years and 80 and older among the regions in China. The overall decline rate of spinal BMD in Chinese males under QCT was about 46.92% over the lifetime, and it declined obviouslyin the 40-49 age group. The overall prevalence of osteoporosis in Chinese male population aged 50 years and above was approximately 11.42%, with the highest prevalence in Southwest China and Central China (14.72% and 13.87%, respectively) and the lowest in North China and South China (8.53% and 7.71%, respectively). Conclusions:A reference of lumbar spine BMD values for healthy males in China based on QCT is established. BMD values were highest in South China and Lowest in Central China.

Objective:To establish the normal reference value of lumbar bone mineral density (BMD) under quantitative CT (QCT) in Chinese healthy adult females and to explore the regional differences.Methods:Total of 35 431 healthy women who met the inclusion criteria of Chinese health quantitative CT big data program were selected in this study. The BMD of the central plane of L 1 and L 2 vertebrae was measured by Mindways′s QCT system, and the mean value was taken. One-way analysis of variance was used to compare the BMD differences of lumbar vertebrae in women of different ages and regions. The subjects were grouped by an age interval of 10 years, and the level of BMD in different regions of the same age group were compaired. Results:The peak BMD of Chinese healthy adult women appeared in the age group of 20-29 years (Northeast China(183.01±24.58) mg/cm 3, North China (188.93±24.80) mg/cm 3, East China (187.54±27.71) mg/cm 3, South China (186.22±33.72) mg/cm 3, Central China (176.33±24.91) mg/cm 3, Southwest China(182.25±28.00) mg/cm 3), and then it decreased with age. The level of BMD in different regions decreased with the age. Before the age of 70 years, BMD in Central and Southwest China was always at a low level((176.23±24.91) to (90.38±28.12) mg/cm 3, 182.25±28.00 to (88.55±25.68) mg/cm 3), lower than those in Northeast China ((183.01±24.58) to (99.69±27.85) mg/cm 3), North China ((188.93±24.80) to (95.89±26.12) mg/cm 3), East China ((187.54±27.71) to (95.65±27.86) mg/cm 3). After 70 years of age, BMD tended to be the same in different regions ( P>0.05). The BMD values in Central China and Southwest China were similar in the age group of 40-60 years ( P>0.05). The BMD values in the health adult femles in the age group of 60 years in different regions of Chinawere all lower than those of bone mass abnormality (all P<0.05). The detection rate of osteoporosis in females over 50 years was the highest in Southwest China (25.65%) and it was the lowest in North China (17.30%). Conclusions:This study establishes reference values of BMD under QCT in healthy Chinese women, which can be used as a reference basis for identifying women with low BMD who are at risk of osteoporosis. The BMD value is the lowest in Southwest China and the highest in South China.

Objective:To use quantitative computed tomography (QCT) technology to measure the bone mineral density of the spine of the Chinese healthy population, and to explore its correlation with hemoglobin and serum albumin.Methods:The data in this study came from the China Health Quantitative CT Big Data Project (China Biobank). The spine bone density was measured by using QCT Pro Image Analysis System and all cooperating centers used the European spine phantom (NO.145) for quality control. Total of 50 053 healthy persons who met the criteria for entry were selected as the research subjects. The subjects were divided into 7 groups according to age. The general data, spine bone density, serum albumin, hemoglobin of the subjects were collected. The single-factor analysis of variance, Pearson correlation analysis and multi-classification logistic regression model were applied to analyze the correlation between bone density and hemoglobin and serum albumin.Results:The bone mineral density of healthy people decreased with age ( P<0.05), and there were significant differences in hemoglobin, serum albumin and body mass index (BMI) among different age groups (all P<0.05). Linear correlation analysis showed that there were positive correlation between bone mineral density and hemoglobin in healthy males in different age groups ( r=0.086, 0.101, 0.076, 0.090, 0.072, 0.123, 0.100, all P<0.01). There were negative correlation between bone mineral density and hemoglobin in certain age groups in women (40-49 years group: r=-0.027; 70-79 yearsgroup: r=-0.077; both P<0.05). And corelation were found between bone mineral density and serum levels of albumin in certain age groups of healthy subjects (among men, 30-39 years group: r=-0.048; 40-49 years group, r=-0.027; 70-79 years group, r=-0.051; among women, 30-39 years group: r=-0.044; 40-49 years group, r=-0.042; 50-59 years group, r=-0.086; 70-79 years group, r=-0.070; all P<0.05). After adjusting for age and BMI, the multi-category logistic regression analysis showed that the hemoglobin level was protective factor of normal bone density ( OR=1.022, 95% CI:1.017-1.027) and decreased bone density ( OR=1.012, 95% CI:1.007-1.016) in healthy males, and the serum albumin was risk factor for normal bone density ( OR=0.926, 95% CI:0.905-0.948) and decreased bone density ( OR=1.006, 95% CI:0.951-1.011) in healthy women. Conclusion:There is a correlation between bone mineral density and hemoglobin and serum albumin in Chinese healthy population. Hemoglobin is a protective factor for bone mineral density in men, and serum albumin is a risk factor for bone mineral densityin women.