Objective To explore the application values of magnetic resonance diffusion weighted imaging (DWI)and diffusion tensor imaging (DTI)in the early diagnosis of cerebral infarction.Methods 1 2 1 patients with single side cerebral infarction were di-vided into five groups by disease time,the brain examination was performed by conventional MRI,DWI and DTI in every case.The le-sions were observed and compared in different sequences imaging.Mean diffusivity(MD)and fractional anisotropy(FA)values of cere-bral infarction lesions and the symmetrical positions in normal hemispheres were measured and compared.The correlations between relative MD(rMD)value,relative FA(rFA)value and disease time were analyzed.Results The display rate on DWI in showing ultra-acute and acute cerebral infarction lesions was 100%,which was superior to that on other sequences of conventional MRI obviously (P<0.05).Compared with the healthy sides,MD values of infarction lesions were lower at ultra-acute and acute phase(P<0.001), but at sub-acute phase,there was no statistically difference between the affected and normal sides(P>0.05).MD value was higher at early chronic and late chronic phase(P<0.001);FA values had no consistent changes at ultra-acute phase(P>0.05),but at the later separate phases,FA values reduced successively(P<0.001).The rMD value of infarction lesions was positive correlated with disease time(rs=0.990,P<0.001).The rFA value of infarction lesions was negative correlated with disease time(rs=-0.994,P<0.001). Conclusion DWI is susceptive in showing cerebral infarction lesions at hyper-early phase.DTI can be used to determine the clinical phase and appraise the inj ured extent of cerebral infarction accurately by measuring the parameters.Combination of DWI and DTI can provide a basis for clinical individual treatment programs selection and prognostic evaluation.

Objective To study the effect of sodium ?-aescin on the matrix metalloproteinase-9 (MMP-9) and laminin (LN) expression in rats after focal cerebral ischemia and reperfusion, and provide experimental evidence for the relationship of MMP-9 and LN expression change with the neuroprotection of sodium ?-aescin. Methods The Spraque-Dawley (SD) rat model of focal cerebral ischemia and reperfusion of cerebral middle artery was prepared. Fifty-six rats were randomly divided into the normal, sham, ischemia and reperfusion, as well as ischemia and reperfusion-treated with sodium ?-aescin groups. The latter two were further divided into six subgroups according to reperfusion time interval of 3h, 6h, 12h, 24h, 72h and 7d after brain ischemia, with 4 rats in each subgroup. Immunohistochemical staining and image analysis were used to measure the expression of MMP-9 and LN in the ischemic region. Results The expression of MMP-9 started to increase at 6h, reached the peak at 12h, decreased in 24h, and reached the lowest on 7d in cerebral ischemia and reperfusion group. The expression of MMP-9 in the same time groups of the cerebral ischemia and reperfusion-treated with sodium ?-aescin group all obviously decreased (P

Objective To describe the understanding level of disease of children with leukemia and their ways of obtaining disease information in order to help nurses and parents to select appropriate content and manners to communicate with children about disease information.Methods In-depth interviews were conducted with 25 children' parents using a descriptive qualitative research method,and the data were analyzed using content analysis.Results Children during remission stage of leukemia had different understanding levels of their disease.Ways of children with leukemia to obtain disease information was correlated with their mental maturity.Conclusions Disease information should be told according to children's age,disease course and level of thinking,and health professionals and parents could provide appropilate ways of obtaining information for children on basis of their mental maturity.

ObjectiveTo explore the diagnostic value of plasma (1, 3)-β-D-glucan test (G test) in diagnosis of invasive fungal infections (IFI) and the influence of albumin on G test.Methods A prospective observational study was conducted. 267 patients admitted to medical intensive care unit (MICU) of Dalian Municipal Central Hospital from January 21st, 2012 to October 31st, 2014 were enrolled. According to IFI guideline, the patients were divided into without IFI group (n= 35), possible IFI group (n = 70), hypotheticle IFI group (n = 145) and proven IFI group (n = 17). G test was examined routinely using microbiology kinetic rapid reader MB-80.The different threshold values were calculated on G test. The difference among G tests, fungal culture and clinical diagnosis were compared. The results of G test ahead of and post albumin administration in each group were compared, and the value of G test for diagnosis of IFI during albumin infusion was evaluated.Results When the cut-off value was 20 ng/L for IFI diagnosis, higher sensitivity (79.8%), specificity (87.9%), and Youden index (67.7%) were found. The positive rates of G test, fungal culture and clinical diagnosis of IFI were 57.7% (154/267), 60.7% (162/267) and 54.3%(145/267) respectively, without showing significant differences (allP> 0.05). The result of G test (ng/L) was not obviously changed after albumin administration compared with that before in without IFI, possible IFI, hypotheticle IFI, and proven IFI groups (without IFI group: 11.25±2.33 vs. 10.99±1.07,t= -1.723,P= 0.085; possible IFI group: 53.14±5.53 vs. 49.22±8.11,t= -0.395,P= 0.693; hypotheticle IFI group: 90.30±9.38 vs. 85.41±10.11, t= 710.500,P= 0.860; proven IFI group: 100.98±19.24 vs. 103.21±17.66,t= 653.000,P= 0.449). Prior to the administration of albumin, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and Youden index were 79.8%, 87.9%, 45.6%, 96.7%, 67.7%, respectively. However, after the administration of albumin, they were 81.5%, 85.7%, 44.8%, 96.5%, and 67.2%, respectively, without significant difference.Conclusions G test is method for early diagnosis of IFI. The sensitivity and specificity are higher with 20 ng/L as the critical value. The result of G test is not interfered by albumin administration.

Objective To observe the protective effect of anthocyanin on irradiation induced bone marrow c-kit positive cell injury, and further explore its possible mechanism. Methods Mouse bone marrow c-kit positive cells were collected by cell sorting method. There were 2 groups: control group and anthocyanin group, which were sub-divided into three groups and received 0 Gy, 1 Gy and 4 Gy irradiation respectively. The control group was added 700μL cell suspension and an equal volume of serum-free hematopoietic stem/progenitor cell culture medium. The 2 × 10-5 mol/L anthocyanin was co-cultured with mouse bone marrow c-kit positive cells of anthocyanin group half an hour before irradiation exposure, then cells were cultured for 18 hours under the conventional culture conditions (37℃,5%CO2). Mouse c-kit positive cell viability was measured by bioluminescence, and which was reflected by relative light units (RLU). The ability of colony-forming units was reflected by CFU-GM. The reactive oxygen species (ROS) level and mean fluorescence intensity (MFI) ofγ-H2AX were detected by flow cytometry. Results Compared to un-irradiated control group, the cell viability and the number of CFU-GM were decreased significantly, while the ROS level and MFI ofγ-H2AX were increased in c-kit positive cells irradiated with 1 Gy and 4 Gy (P<0.05). Compared to 1 Gy and 4 Gy irradiation groups, c-kit positive cell viability and the number of CFU-GM were increased, the ROS level and MFI of γ-H2AX were decreased in anthocyanin group (P < 0.05). Conclusion Anthocyanin exhibits a promising protective effect on radiation-induced bone marrow c-kit positive cell injury, which may be related to the alleviating ROS and DNA damage in bone marrow cells.

Objective To investigate the protective effect of hydrogen-rich water (HRW) on radiation-induced hematopoietic stem and progenitor cells (HSPCs) injury.Methods Totally 32 C57BL/6 mice were randomly divided into four groups with 8 mice in each group,including control,HRW,radiation and radiation + HRW.Mice in HRW and radiation + HRW groups received 0.5 ml hydrogen-rich water per day by intragastric administration 5 min before irradiation until 7 d post-irradiation.Mice in other groups received 0.5 ml distilled water.Mice in radiation and radiation + HRW group were irradiated with 2 Gy of total body irradiation.Bone marrow cells were isolated at 15 d post-irradiation,and LSK cells were examined for the percentage of hematopoietic stem and progenitor cells,the ability of colony formation and reconstitution,reactive oxygen species (ROS) levels and cell apoptosis.Results Compared with radiation group,the percentages of hematopoietic progenitor cells and LSK cells,colony number of bone marrow cells were significantly increased in radiation + HRW group (t =-4.935,-7.898,5.488,P ＜ 0.05).An elevation of donor chimerism was also found in recipient mice administered HRW after competitive bone marrow transplantation (t =-12.769,P ＜ 0.05).Compared with radiation group,the ROS levels and cell apoptosis in LSK cells were significantly decreased (t =4.380,3.954,P ＜ 0.05).Conclusions Hydrogen-rich water exhibited a protective effect on radiation-induced HSPCs injury.

Objective To investigate the protective effect of theaflavins on thymus injury caused by total body irradiation (TBI).Methods Twenty-five C57BL/6 mice were randomly divided into 5 groups:control group,4 Gy TBI group,4 Gy TBI + 25 mg/kg theaflavins group,4 Gy TBI + 50 mg/kg theaflavins group and 4 Gy TBI + 100 mg/kg theaflavins group.Thymus index and total number of thymocytes were detected at the 14th d post-irradiation to determine the optimal dose of theaflavins.According to this optimal dose,32 C57BL/6 mice were randomly divided into 4 groups:control group,theaflavins group,4 Gy TBI group and 4 Gy TBI + theaflavins group.Thymus histomorphology,CD4CD8 T cell subsets,and reactive oxygen species (ROS) in thymocytes were examined at the 14th d post-irradiation.Results The irradiated thymus exhibited decreased thymus index and total number of thymocytes (P ＜ 0.05),aberrant histomorphology and T cell subsets (P ＜ 0.05),and increased ROS level in thymocytes (P ＜ 0.05).Compared with 4 Gy TBI group,the thymus index and total number of thymocytes were significantly increased in 4 Gy TBI + 50 mg/kg theaflavins group (P ＜ 0.05).The total number of thymocytes was significantly higher in 4 Gy TBI + 50 mg/kg theaflavins group than that in 4 Gy TBI + 25 mg/kg theaflavins group (P ＜ 0.05).Therefore,50 mg/kg theaflavins was chosen as the optimal dose for subsequent experiments.Moreover,the aberrant histomorphology of irradiated thymus was alleviated by theaflavins.A decline in the percentage of CD4-CD8-T cells and an elevation of CD4+CD8-and CD4+CD8+ T cells were found in irradiated mice administered with theaflavins (P ＜ 0.05).Compared with 4 Gy TBI group,the ROS level was significantly decreased in 4 Gy TBI + theaflavins group (P ＜ 0.05).Conclusion Theaflavins exhibits a protective effect on radiation-induced thymus injury.

Objective To explore the effect of mefformin on glucose metabolism of rat myoblast with high fat environment.Methods The skeletal muscles of suckling Wister rats were subjected to primary culture.The myoblasts of passage 5 were divided into 5 groups:The control group was cultured in DMEM with 0.5％ BSA for 12 h.The high-fat group was exposed to 0.3 mmol/L palmitic acid for 12 h.On the basis of high-fat treatment,three intervention groups were added with 2.5,5.0 and 7.5 μg/ml metformin,respectively,for additional 24 h.Isotope tracer method was conducted to show the influence on 2-dexoy-D-[3H]glucose uptake of rat myoblast.Results With the increasing concentration of mefformin,[3H]-G uptake elevated [ ( 1.83 ± 0.34) 10-2pmd/( min · g) vs (2.33 ± 0.47 ) 10-2 pmd/( min · g),P ＜ 0.05 ],and the group of 7.5 μg/ml metformin uptakes the most.Conclusions Metformin can upregulate the glucose-uptake in rat myoblasts under the environment of high fat,and it shows a dose-dependent relationship.

The current problems with corneal transplant,including shortage of donors and immune rejection,could be effectively solved by constructing cornea in vitro with tissue engineering techniques,in which the selection of suitable scaffold materials is especially critical.Chitosan and its derivatives are natural biomaterials with excellent biocompatibility,biodegradability,mechanical property and plasticity,indicating wide application prospects in corneal tissue engineering.This article systematically reviews the research advances in chitosan and its derivatives in corneal tissue engineering,and the existing problems are also highlighted in order to provide theoretical basis for further clinical research.

Objective : To investigate the prevalence of occupational injury and identify its influencing factors among workers in a steel enterprise in Gansu Province, so as to provide insights into prevention of occupational injury among steel workers. Methods: Workers were sampled from a steel enterprise in Gansu Province using a cluster sampling method from January to March 2022, and participants' demographics, occupational history and occupational injury were collected using questionnaire surveys. The type of job and site and type of injury were analyzed among workers with occupational injuries, and factors affecting workers' occupational injuries were identified using a multivariable logistic regression model. Results: A total of 12 089 questionnaires were allocated and 10 725 valid questionnaires were recovered, with an effective recovery rate of 88.71%. The respondents included 9 412 males (87.77%) and 1 312 females (12.23%), and had a median age of 36.00 (interquartile range, 15.00) years. Junior college and above was the predominant educational level (6 056 workers, 56.47%), and the respondents had a median length of service of 10 (interquartile range, 11) years. The prevalence of occupational injury was 5.25% among respondents. Overhaul worker was the main type of job (11.90%), and object strike was the predominant type of occupational injury (18.25%), while the lower limb was the predominant site of injury (27.82%). Multivariable logistic regression analysis identified men (OR=2.464, 95%CI: 1.580-3.843), age (30 to 39 years, OR=2.561, 95%CI: 1.643-3.993; 40 to 49 years, OR=5.197, 95%CI: 2.679-10.079; 50 years and older, OR=10.620, 95%CI: 6.788-16.615), exposure to high temperature (OR=1.400, 95%CI: 1.165-1.683), operating equipment failure (OR=1.291, 95%CI: 1.048-1.591), absence of personal safety protection equipment (OR=1.555, 95%CI: 1.064-2.273) and safety behavior scores (OR=0.967, 95%CI: 0.937-0.996) as factors affecting occupational injuries among workers in a steel enterprise. Conclusions Men and overhaul workers are at a high risk of occupational injuries in this steel enterprise. Objectstrike is the predominant type of injury and lower limb is the main site of injury. The risk of occupational injuries is affected by gender, age, working environments, equipment status and safety behaviors.