Objective To investigate the CT perfusion imaging and the pathological features on the disturbance of regional cerebral microcirculation in a pre-infarction period, and to evaluate the relationship between the astrocytes and regional cerebral microcirculation. Methods Dynamic CT perfusion imaging of the models with regional cerebral hypoperfusion and astrocytic swelling in rats was performed to assess the presence or absence of the disturbance of regional cerebral microcirculation. Then, the histopathologic examination was made for both models, respectively. The ratios of side-to-side were measured at hypoperfusion areas in the models of regional cerebral ischemia. Results Regional hypoperfusion was revealed by regional cerebral blood flow (rCBF) and mean transit time (MTT) maps in the group of hypoperfusion for 6 hours. Regional cerebral blood volume (rCBV) and time-to-peak (TTP) maps were normal in that group. The ratios of rCBF, rCBV, MTT and TTP were 0 39-0 55, 0 92-1 00, 1 20-1 50 and 1 00-1 00 respectively. Astrocytic swelling pressing the capillary wall was obvious and subtle neuronal reversible degeneration was occasionally found. TTC stain was normal. In the tACPD group of astrocytic swelling, the abnormal hemodynamic regions on rCBF and MTT maps were found. The rCBV maps of 3 rats in the tACPD group showed the area of reduced rCBV. In 2 rats of tACPD group, the areas of delayed TTP were also found. The ratios of rCBF, rCBV, MTT and TTP were 0 25-0 44, 0 70-1 01, 1 20-2 00 and 1 02-1 45 respectively. TTC stain was negative. Electron microscope study revealed remarkable swelling of astrocytes, especially endfoot processes of astrocytes around capillaries. The abnormal hemodynamic region on rCBF and MTT maps matched with abnormal extent on histopathologic examination. The rCBV and TTP maps appeared normal. Conclusion The astrocytes can react in a way faster than the neurons in the pre-infarction period, viz. astrocytic swelling. The swelling of astrocytic foot, which pressed capillary vessel, induced the disturbance of regional cerebral microcirculation, and then aggravated hypoxic ischemic state in regional brain parenchyma. Perfusion CT and its parameters' analysis may play an increasing role to delineate the reversible hypoperfusion areas in pre-infarction period. Analyzing the relationship of rCBF and rCBV is very helpful to know the status of the capillary vessels in regional cerebral hypoperfusion area.

Objective To establish a stable and controllable model of acute regional cerebral ischemia in rats, and to evaluate it by CT perfusion imaging and histological study. Methods Twenty eight male Wistar rats were randomly divided into 4 groups, and there were 7 rats in each group. The sham operation rats were defined as the first group, rats suffered from cerebral ischemia for 15 minutes were classified as the second group, rats suffered from cerebral ischemia for 30 minutes and then reperfusion for 1 hour as the third group, and rats suffered from hypo perfusion for 6 hours as the fourth group. Cerebral ischemia or hypo perfusion were induced by inserting a nylon thread of different diameter into right middle cerebral artery (MCA) of rats under the monitoring of regional cerebral blood flow (rCBF) by the Laser Doppler Blood Perfusion Monitor (BPM). rCBF was also examined by dynamic CT perfusion imaging. At the end of the observation time, rats were decapitated, and three rats of each group were performed 2,3,5 triphenyltetrazolium chloride (TTC) staining and four rats were performed histological study. Results In the second group, rCBF was controlled within 5% to 22% under the monitoring by BMP and CT perfusion imaging showed the decreased rCBF in 7 rats, but TTC staining showed red appearance indicating no infarction focus formed. Electronic microscopic study revealed astrocytic swelling and a few of neuronal degeneration. In the third group, rCBF was controlled within 4% to 23% under the monitoring by BMP. There were more severe astrocytic swelling and a lot of neuronal degeneration. The abnormal areas in CT perfusion images were the same as TTC staining. In the fourth group, in accordance with less decrease ment of rCBF (from 38% to 55%) in 7 rats, there were obvious astrocytic swelling and subtle neuronal degeneration. TTC stain did not show ischemia area. All these abnormal changes were not observed in the sham operation rats. Conclusion The controllable acute regional cerebral ischemic model in rats is very stable and repeatable. It can be simulated into the ischemic state of different perfusion level. This model is suitable for the research of acute cerebral infarction and regional cerebral ischemia. The facts that parallel changes existed among BMP measurement, CT perfusion imaging, and brain histology indicated that CT perfusion imaging is accurate and sensitive in evaluating acute regional ischemia.

BACKGROUND:Chitosan biological materials can induce bone marrow mesenchymal stem cells to differentiate toward neurons. As a derivative of chitosan, carboxymethyl chitosan has a series of excelent properties. However, whether carboxymethyl chitosan can induce the neuronal differentiation of bone marrow mesenchymal stem cells remains unclear.OBJECTIVE:To investigate the effect of carboxymethyl chitosan thermosensitive hydrogel on the differentiation of bone marrow mesenchymal stem cells into neurons and the possible mechanism.METHODS:Passage 3 bone marrow mesenchymal stem cells from rats were selected and cultured in carboxymethyl chitosan thermosensitive hydrogel extracts in different concentrations (0, 50, 100, 150, 200, 500 g/L). Control cells were cultured in culture medium with no addition of carboxymethyl chitosan thermosensitive hydrogel extracts. MTT assay was performed to investigate the effects of different concentrations of carboxymethyl chitosan thermosensitive hydrogel extracts on bone marrow mesenchymal stem cell proliferation. Western blot assay was used to explore the effect of 150 g/L carboxymethyl chitosan thermosensitive hydrogel extracts on the expression of neuron-specific enolase, Nestin, Vimentin, NF-M, microtubule associated protein 2, glial fibrillary acidic protein, β3-tubulin, Notch1 and Jag1 protein.RESULTS AND CONCLUSION:MTT assay showed that carboxymethyl chitosan thermosensitive hydrogel promoted the cell proliferation, and the proliferation rate reached the peak at the concentration of 150 g/L. Western blot assay showed that the cells induced by 150 g/L carboxymethyl chitosan thermosensitive hydrogel extract had significant increases in neuron-specific enolase, Nestin, Vimentin, NF-M, microtubule associated protein 2, glial fibrillary acidic protein, and β3-tubulin protein expression, and obvious decreases in Notch1 and Jag1 protein expression in comparison with the control group. These results indicate that the carboxymethyl chitosan thermosensitive hydrogel induces rat bone marrow mesenchymal stem cells to differentiate toward neurons, and suppresses the activity of Notch signal pathway in the process of differentiation.

Objective To investigate the causes of death and the influencing factors in patients with peripheral arterial disease(PAD) during the perioperative period and reduce the perioperative mortality.Methods A retrospective analysis of the causes of death was performed for PAD during the perioperative period in our hospital from July 2005 to July 2010. Results Nine patients died preoperatively.The causes of death were multible organ failure in 5,heart failure in 2,sudden cardiac death in 1,and respiratory failure in 1.Six patients died postoperatively.The causes of death were acute renal failure in 2,heart failure in 2,cerebral infarction in 1,and hemorrhagic shock in 1.The causes of death which were related to heart,kidney and lung were in 10,6 and 2,respectively.The causes of death which were directly due to heart failure,sudden cardiac death,renal failure,respiratory failure,cerebral infarction and hemorrhagic shock were in 4,1,2,1,1 and 1,respectively.The main causes of death were multible organ failure,heart failure and acute renal failure,which accounted for 73.33％ of all deaths.In this series the overall perioperative mortality was 3.11％ (15/483),Operative mortality was 1.47％ (6/407).Conclusions The influencing factors and the function of organs were closely correlated with the causes of death. To reduce the perioperative mortality of PAD,it is necessary both to intervene in the influencing factors and to monitor and treat the dysfunction of vital organs.

Objective To Establish an evaluation system of the quality of life for Chinese liver and kidney transplant recipients,and develop a specialized scale to measure the quality of life (QOL)for such recipients preliminarily.Methods By combining subjective and objective methods,this study determined the evaluation system and created items of QOL scale based on literature analysis,Delphi method (expert consultation),interviews,and experience of researchers.Then,a nationwide clinical survey was conducted on 5 Level Ⅲ Class A hospitals.454 valid questionnaires were collected,including 153 from liver recipients,and 301 from kidney recipients.Subjective statistical methods such as critical Ratio method,correlation coefficient method,dispersion tendency method,and exploratory factor analysis were used for selection of questionnaire items.Results The study established an evaluation system of QOL for liver and kidney transplant recipients,including 4 primary indexes and 12 secondary indexes,and developed QOL scales that were appropriate for liver and kidney transplant recipients respectively.Conclusions The structure of QOL scale for liver and kidney transplant recipients was basically consistent with theoretical assumption.The QOL scale for patients showed good reliability and validity,therefore,it can fully reflect the quality of their life.

Objective:To explore the clinical pathological characteristics and initial 131I curative responses of familial differentiated thyroid cancer (FDTC) and sporadic differentiated thyroid cancer (SDTC). Methods:A total of 66 FDTC patients (19 males, 47 females, age (39.8±11.7) years) and 1 701 SDTC patients (442 males, 1 259 females, age (40.9±11.3) years) who underwent 131I therapy in Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology between January 2010 and August 2018 were retrospectively enrolled. The clinical pathological characteristics, preablative stimulated thyroglobulin (ps-Tg), preablative stimulated thyroglobulin antibody (ps-TgAb) and response to initial therapy (excellent response, indeterminate response, biochemical incomplete response, structural incomplete response) of two groups were analyzed and compared. The clinical pathological parameters included age, gender, pathological type, tumour maximum diameter, bilateral, multifoci, nodules goiter, thyroiditis, thyroid membrane invasion, lymph node metastasis (LNM), invasion of the surrounding soft tissues, distant metastasis, TNM staging and American Thyroid Association (ATA) risk stratification (low-risk, intermediate-risk, high-risk). χ2 test or Fisher exact test and independent-sample t test were used to compare the data between two groups. Results:Comparing with SDTC group, FDTC group showed higher proportion of bilateral foci (45.5%(30/66) vs 31.2%(530/1 701); χ2=5.999, P=0.010), thyroid membrane invasion (43.9%(29/66) vs 26.6%(452/1 701); χ2=9.672, P=0.002) and distant metastasis (15.2%(10/66) vs 6.2%(105/1 701); χ2=8.418, P=0.004). There was a statistical difference in risk stratification between two groups (high-risk: 18.2%(12/66) vs 9.2%(156/1 701); intermediate-risk: 68.2%(45/66) vs 72.7%(1 237/1 701); low-risk: 13.6%(9/66) vs 18.1%(308/1 701); χ2=6.898, P=0.030). But the tumor maximum diameter of FDTC group was smaller than that of SDTC group ((1.24±0.74) vs (1.50±0.92) cm; t=-2.275, P=0.020). There were no significant differences in other clinical pathological parameters between FDTC group and SDTC group ( t=-0.804, χ2 values: 0.101-5.359, all P>0.05). There were no significant differences between two groups in the postoperation ps-Tg, ps-TgAb levels and the response to initial therapy after 131I treatment ( χ2 values: 0.059-1.915, all P>0.05). Conclusions:The FDTC group displays distinct characteristics as increased aggressiveness at diagnosis. But after accurately treatment, there is no significant difference in the response to therapy between two groups.

Objective To explore the factors associated with the quality of life (QOL) in patients after liver and kidney transplantation.Methods A multicenter cross-sectional survey was carried out in 5 Level Ⅲ Class A hospitals.153 liver transplant recipients and 301 kidney transplant recipients of outpatient clinic follow-up from March to December in 2015 were selected and investigated with a self-designed general state questionnaire,and Quality of Life Scale for Liver and Kidney Transplant Recipients which developed by our research group.Results There were significant differences in QOL total score in liver and kidney transplant recipients among groups of marital status and occupation.Divorced,unemployed and low-educated patients showed lower QOL total score than married,employed and high-educated ones (P ＜ 0.05).As compared with non-living-related transplantation group,patients undergoing living-related transplantation presented a better status in QOL total scores (P＜0.05).The QOL total score was obviously lower in patients suffering from complications and rejection than in those without occurrence of complications and rejection (P＜ 0.01).Postoperative time was correlated positively and significantly with QOL scores,and variances existed among different stages postoperation (P ＜ 0.01).Multivariable regression analysis demonstrated that education,marital status,postoperative time,type of donor and chemotherapy were the factors influencing liver transplant recipients' QOL,while marital status,postoperative time,type of donor,medical care assurance,complications and rejection after operation had effect on kidney transplant recipients.Conclusion Attaching importance to QOF among liver and kidney transplant recipients,and implementing scientific and effective nursing intervention based on the characteristics of them are necessary.

Objective:To systematically evaluate the effect of hydrocortisone combined with vitamin C and vitamin B1 on the efficacy of patients with sepsis or septic shock.Methods:Databases including CNKI, Sino Med, VIP, Wanfang, PubMed, the Cochrane Library, and Embase were searched from inception to January 2021 for the randomized controlled trial (RCT) about hydrocortisone combined with vitamin C and vitamin B1 to treat sepsis or septic shock. The experimental group was given intravenous injection of hydrocortisone, vitamin B1 and vitamin C based on conventional treatment; the control group was given conventional treatment or placebo/hydrocortisone/hydrocortisone+vitamin B1 based on conventional treatment. Outcome indicators included sequential organ failure assessment (SOFA), mortality, the duration of vasoactive drugs, new acute kidney injury (AKI) patients, length of stay in intensive care unit (ICU) and in hospital. Two researchers independently screened the literature, extracted data, and evaluated the risk of bias in the included studies. RevMan 5.3 software was then used to perform Meta-analysis. Funnel plot was used to test publication bias.Results:A total of 6 articles involving 816 patients were included, with 411 patients in the experimental group and 405 patients in the control group. The Meta-analysis results showed that the duration of vasoactive drugs in the experimental group was significantly shorter than that in the control group [mean difference ( MD) = -24.02, 95% confidence interval (95% CI) was -32.36 to -15.68, P < 0.000 01]. However, there were no significant differences in SOFA, mortality, new AKI patients, the length of ICU stay and hospital stay between the two groups [SOFA: MD = -0.14, 95% CI was -1.15 to 0.87, P = 0.79; mortality: relative risk ( RR) = 0.99, 95% CI was 0.81 to 1.21, P = 0.92; new AKI patients: RR = 1.10, 95% CI was 0.42 to 2.87, P = 0.84; length of ICU stay: MD = 1.33, 95% CI was -2.22 to 4.89, P = 0.46; length of hospital stay: MD = 1.02, 95% CI was -0.66 to 2.69, P = 0.23]. The funnel plot showed that most of the points were symmetrical and showed an inverted funnel shape, suggesting that the publication bias among the studies was small. There was no significant publication bias on this Meta-analysis. Conclusions:Hydrocortisone combined with vitamin C and vitamin B1 can shorten the duration of vasoactive drugs in patients with sepsis or septic shock, but it cannot effectively reduce the SOFA score, mortality, new AKI patients, length of stay in ICU and in hospital. Limited by the number and quality of the included studies, further large-scale, multi-center, blinded, RCT are still needed for verification.

Multiple sclerosis (MS) is one of the demyelinating diseases of the central nervous system, and its pathogenesis is still unclear. Magnetic resonance imaging (MRI) is an effective tool for the diagnosis and monitoring of MS, and the identification of MS lesions is increasingly updated with the development of technology. In recent years, 7.0 T ultra-high field MRI has been widely used in MS. This review will make an overview of the research progress of 7.0 T ultra-high field MRI in MS in recent years.

Objective To investigate the changes and related factors of maternal thyroid autoantibodies during early pregnancy. Methods Urinary iodine concentration( UIC) , serum thyroid stimulating hormone( TSH) , free thyroxine ( FT4 ) , thyroid-peroxidase antibody ( TPOAb ) , thyroglobulin antibody ( TgAb ) concentrations were determined in 7 190 women during early pregnancy in an iodine-sufficient region of China. Results The prevalence of TPOAb positivity and TgAb positivity were 8. 7% and 12. 0% respectively. The prevalence of overt hypothyroidism and subclinical hypothyroidism increased significantly in group of thyroid antibody positivity. The prevalence of TPOAb positivity and TgAb positivity presented a U-shaped curve, ranging from mild iodine deficiency to iodine excess, especially increased significantly in the group with UIC<100 μg/L. Conclusion Prevalence of thyroid antibodies positivity became higher during early pregnancy. The positive thyroid autoantibodies during pregnancy were significantly associated with maternal hypothyroidism. Both iodine excess and iodine deficiency are risk factors of positive thyroid antibodies.