Objective: To investigate the effects of different doses of X ⁃rays irradiation combined with allogeneic lymphocyte infusion on the establishment of aplastic anemia in mice. Methods: Forty BALB/c mice were randomly divided into four groups : the 3 Gy group (n = 9) , the 4 Gy group (n = 9) , the 5 Gy group (n = 10) , and the con⁃trol group (n = 12) . In the 3 Gy , 4 Gy , and 5 Gy groups , the experimental mice were exposed to corresponding do⁃ses of X ⁃ray and then intravenously infused with 0. 2 mL mixed suspension of the thymus and spleen cells from DBA/2 mice , at a concentration of 1 × 107 cells/mL , within 4 hours after irradiation. The control group did not un⁃dergo X ⁃ray irradiation and infused with an equivalent volume of physiological saline instead. Blood samples were collected from the orbital venous plexus of BALB/c mice and analyzed using an animal automated hematology analy⁃zer to measure peripheral blood parameters , including red blood cells ( RBC) , white blood cells ( WBC) , and platelets (PLT) . The general condition of mice was monitored daily , and survival rates were recorded for each group. At the experimental endpoint , the tibias were harvested for hematoxylin and eosin (HE) staining , while the femurs were used to prepare bone marrow smears for morphological examination. For the 5 Gy group , T ⁃cell subsets(ELISA) at the endpoint. Results : In the 3 Gy group , pancytopenia was observed , but platelet recovery occured rapidly , returning to normal levels by day 17 post⁃modeling. No deaths occurred during the observation period. At myeloid⁃to⁃erythroid (M/E) ratio , and no significant morphological abnormalities were noted in cells at any devel⁃with hematopoietic cells. In the 4 Gy group , pancytopenia persisted throughout the observation period. The survival rate was 90% . Endpoint analysis showed hypocellular marrow by morphological examination. HE staining indicated minimal fatty infiltration in the bone marrow tissue. In the 5 Gy group , pancytopenia was observed , though erythro⁃cyte counts returned to normal levels by day 24. The survival rate during the observation period was 50% . Endoint analysis revealed vacuolization of marrow particles and reduced hematopoietic cells with predominantly non⁃hematopoietic cells in bone marrow morphology. HE staining demonstrated severe fatty infiltration in the bone mar⁃row tissue , with scarcity of immature cells and hematopoietic precursor cells. Flow cytometry analysis showed a de⁃creased proportion of CD4 + T cells (% ) and an increased proportion of CD8 + T cells (% ) . ELISA confirmed elevated secretion of negative hematopoietic regulators : interferon⁃gamma ( IFN⁃γ) and tumor necrosis factor⁃alpha (TNF⁃α ) . Conclusion Combined administration of varying radiation doses with allogeneic lymphocyte infusion consistently induced peripheral blood cytopenia in mice , characterized by reductions in RBC , WBC , and PLT counts. Integrated analysis of bone marrow morphology , histopathological assessment via HE staining , and immuno logical parameters confirmed that a mouse model of aplastic anemia can be successfully established using 5 Gy X ⁃ ray irradiation coupled with infusion of 2 × 106 allogeneic lymphocytes.

Objective To analyze the imaging characteristics and to evaluate the application value of color doppler ultrasonography (CDUS)combined with CT angiography (CTA)and contrast-enhanced magnetic resonance angiography (CE-MRA)in patients with cervical vertigo.Methods 62 patients diagnosed with cervical vertigo clinically were enrolled.Neck CDUS and neck CTA were per-formed on 39 patients.Neck CDUS and neck CE-MRA were performed on 23 patients.Neck CDUS and CTA/MRA were performed on 30 normal volunteers,which were chosen as control group.Neck CDUS and neck CTA were performed on 18 normal volunteers. Neck CDUS and neck CE-MRA were performed on 12 normal volunteers.Hemodynamics and morphology were evaluated and com-pared between the two groups.Results In aspect of morphology:The incidence of vertebral artery (VA)stenosis (46.77%)and VA variation (29.03%)in cervical vertigo group were higher than VA stenosis (23.33%)and VA variation (6.67%)in control group with significant difference (all P <0.05).The incidence of tortuous VA showed no statistics difference between cervical vertigo group (1 1.29%)and control group (13.33%)(P >0.05).In aspect of hemodynamics:The decline incidence of peak systolic velocity de-tected by CDUS in cervical vertigo group (66.13%)was higher than that in control group (10.00%)with statistically significant difference (P <0.05).The peak systolic velocity decline incidence of VA stenosis (86.21% )and VA variation (72.22%)were high-er than that of VA tortuous (28.57%)and VA normal (12.50%)patients in cervical vertigo group.Conclusion The application of CDUS combined with CTA or CE-MRA could provide valuable diagnostic and therapeutic information for cervical vertigo in the as-pects of change in vascular morphology and cerebral hemodynamics,which could further provide objective basis for clinical diagnosis and treatment.

Objective To estimate the value of computed tomography perfusion for clinical stage and approach the correlation of perfusion parameters and Cyfra21-1.Methods 63 patients with head and neck squamous carcinoma were confirmed by pathology and follow up underwent CT perfusion,which were divided into three groups by international clinical staging criteria(stageⅠ,stageⅡand stageⅢ-Ⅳ).BF,BV,MTT,TTP and Cyfra21-1 were recorded and compared with correlation in different clinical staging.Results There was no significant difference of Cyfra21-1 between stageⅠand stageⅡ(Z =1.439,P =0.1 62).There was significant differ-ence of Cyfra21-1 between stageⅠand stageⅢ-Ⅳ(Z =3.356,P =0.000),stageⅡand stageⅢ-Ⅳ(Z =4.959,P =0.000).There was significant difference of BF and BV between stageⅠand stageⅡ,stageⅠand stageⅢ-Ⅳ(P <0.05),of MTT and TTP between stageⅠand stageⅢ-Ⅳ,stageⅡand stageⅢ-Ⅳ(P <0.05).There was no significant difference of BF and BV between stageⅡand stageⅢ-Ⅳ(P >0.05),of MTT and TTP between stageⅠand stageⅡ(P >0.05).Cyfra21-1 and perfusion parameters in all groups have relationship(r=0.76,0.76,-0.82,-0.82,P <0.05).Conclusion The statistically significant of positive correlation be-tween Cyfra21-1 and perfusion parameters in head and neck squamous carcinoma suggests that CT perfusion could play a complemen-tary role in clinical assessment.

Objective To develop a model that could roundly show the phenotypes of human alzheimer disease (AD), the triple-transgenic rat model harboring APP(Swe), PS1dE9, and TAU transgenes was established in view of the advantage of rat as an important animal model on the research of nerve system .Methods APPswe/PS1dE9/TAU triple transgenic rat AD rats were generated on a SD background by co-injecting rat pronuclei with two human genes driven by the mouse prion promoter:‘Swedish’ mutant human APP (APPsw) and exon 9 mutant human presenilin-1 (PS1dE9) and human microtubule-associated protein tau gene under the control of PDGF promoter .Transgene integration was confirmed by genotyping and expression levels were evaluated by western blot ( WB ) of brain homogenates .The pathological changes were detected by human Abeta, TAU and Phospho-PHF-TAU immunohistochemistry staining (IHC).The behavioral and cognitive changes were evaluated by Morris water maze .Results One transgenic rat lines with high human APP ( Swe ) , PS1dE9, and TAU transgenic expression was selected from three transgenic founders .Compared with the wild type rat , the transgenic rat showed significant learning and memory impairments in the Morris water maze at 6 months of age .The triple transgenic rat manifested hyperphosphorylated tau and obvious aggregation of amyloid -β( Aβ) in the brain cortex and hippocampus.Conclusion APPswe/PS1dE9/TAU triple transgenic rat AD model was established .The triple transgenic AD rat fills a critical need for a next-generation animal model to enable basic and translational AD research .

Objective To investigate the application value of diffusion-weighted imaging with background suppression (DWIBS) in lymph node metastasis of rectal cancer.Methods 30 patients with rectal cancer diagnosed by colonoscopy underwent routine MRI and DWIBS examinations.Metastatic and non-metastatic lymph nodes were confirmed by postoperative pathology.Apparent diffu-sion coefficient (ADC)values of the solid part of metastatic and non-metastatic lymph nodes were measured and compared.ROC curve analysis was used to define the threshold between the metastatic and non-metastatic lymph nodes.Results In all 73 lymph nodes,there were 52 metastatic lymph nodes and the other 21 were non-metastatic.ADC values of the solid part of metastatic and non-metastatic lymph nodes were (0.881 ± 0.094)× 10 -3 mm2/s and (1.072 ± 0.108)×10 -3 mm2/s respectively,the difference was statistically significant (P <0.05).With the threshold ADC value of 0.957×10 -3 mm2/s,the sensitivity and specificity for dif-ferentiating metastatic from non-metastatic lymph nodes were 90.5% and 80.8% respectively.The diagnostic value was excellent (Az value = 0.91 9,P <0.05).Conclusion ADC values may be used to differentiate lymph node metastasis of rectal cancer,and DWIBS has higher application value in assessing lymph node metastasis of rectal cancer.

Objective To obtain more physiological data of Leptin knockout SD rats available for the user , the long-term observation of fasting blood glucose and pathological phenotypes were performed .Methods The protein expression levels in liver tissues were determined by western blot .Body weight of Leptin knockout rats ( Leptin-/-) and littermate lean rats (Leptin+/+) were weighed up at 1,3,6,8 months of age.Fasting blood glucose of Leptin +/+rats and Leptin-/-rats at 1,3,6,8 months of age were measured using One Touch? brand blood glucose monitoring systems.Pathological changes of pancreas and livers of Leptin -/-rats were observed by the method of HE staining and Immunohistochemistry (IHC).Results Short null Lepin proteins were expressed in liver tissues from Leptin -/-rats. Leptin-/-rats become heavier than Leptin +/+rats since they were one month old .The body weight of Leptin -/-rats at 8 months of age was twice as heavy as Leptin +/+rats, female Leptin-/-rats weighing 884g, and male Leptin-/-rats weighing 1200g.Overt hyperglycemia was observed during the first month after birth .Compared with Leptin+/+female rats,the fasting blood glucose of Leptin -/-female rats was increased by 40%-26%from 1 to 6 months old. After that, blood glucose values decreased and eventually become nearly normal at 8 months of age.Pathological examination indicated that Leptin -/-rats at 8 months of age had a fatty liver , more pancreas islets with lager volume and more beta cells with increased insulin secretion .Conclusion Leptin-/-rat were characterized by obesity , fatty liver, islet cell hyperplasia and early hyperglycemia .

Objective To investigate the functional role of 25 microRNAs in breast cancer ,and to find new tumor suppressor microRNAs that may serve as specific targets of new gene therapies . Methods Twenty-five microRNAs expression vectors were constructed and stably transfected into mouse mammary tumor cells 4To7 by Lipofectamine2000. Cells were selected with G418 and sorted by Flow cytometry.The cells in logarithmic phase were collected and 2 ×105 cells/mouse was inoculated into BALB/c mice via tail vein .Lungs were harvested 14 days after tumor cell inoculation , and the number of metastasis foci was counted .Results Mice inoculated with mir-449a-expressing 4To7 cells via tail vein developed reduced lung metastases compared with mice inoculated with negative control cells .Mice inoculated with mir-1935-expressing 4To7 cells via tail vein developed increased lung metastases compared with mice inoculated with negative control cells .Other twenty-three microRNAs neither promoted nor inhibited lung metastases of breast cancer .Conclusions Two of twenty-five microRNA were identified to be associated with breast cancer metastasis .MiR-449a may play a tumour suppressor role in the regulation of migration and metastasis in breast cancer .miR-1935 transgenic over-expression promoted tumor growth and metastasis .

Objective To approach the application value of diffusion weighted imaging with background suppression (DWIBS) combined with routine MR sequence in differentiating benign and malignant lymph nodes,and assessing therapeutic effect of lympho-genic tumors.Methods 48 patients with cervical lymph node enlargement who were confirmed by pathology and follow up under-went DWIBS and routine MRI examination,malignant lymph nodes were 83,benign lymph nodes were 79.16 patients with malig-nant lymph nodes were rechecked after radiotherapy and chemotherapy,Apparent diffusion coefficient (ADC)values of the solid part for lymph nodes were compared.Results More lymph nodes can be detected in DWIBS than conventional sequence.ADC values of the solid part for malignant lymph node(0.898±0.111)×10-3 mm2/s were lower than that of benign lymph node(1.043±0.106)× 10-3 mm2/s,there was significant difference between them (P<0.05).ADC values of all malignant lymph nodes after treatment (1.205±0.121)×10-3 mm2/s were significantly higher than that of pretherapy (0.883±0.090)×10-3 mm2/s (P<0.05).Conclu-sion DWIBS could more sensitively detect lymph node than conventional MR sequence.ADC value could provide some reference values for differentiating benign and malignant lymph nodes and assessing therapeutic effect.

OBJECTIVETo introduce algorithms for effective segmentation of teeth MRI-UTE image.

METHODSTo construct second-segmentation algorithm process based on layer-dependent multi-constrained method. Firstly, a level set method was used to segment the initial boundary from the region determined by user in the reference slice. Secondly, both crown and root of the tooth were segmented by the improved level set method which took the information of the former layer's result as constraint conditions. Finally, the improved level set based on the information of the former and later layer's results was executed for the second time to improve the accuracy of segmentation, in which, the parameter of the overlapping ratio was considered.

RESULTSThe accuracy was 86.98% for the first-segmentation and was increased to 88.35% for the second-segmentation. Compared to the two other methods, the accuracy of the algorithms provided was improved significantly (P < 0.05).

CONCLUSIONSThe proposed algorithms can effectively achieve the segmentation of teeth MRI-UTE image and has a great improvement on accuracy.

OBJECTIVETo segment veins from brain susceptibility weighted images with inhomogeneous background and veins, noises and complex structures.

METHODSBased on vessel enhancing filtering, an adaptive threshold segmenting method and an adaptive threshold region growing method were proposed. The former method was used to exactly segment part of veins from the original images. Taking the veins segmented by the former method as seeds, the later method was used to extract nearly all the veins.

RESULTSFor simulation data with serious noises and interferences, correct rate above 90% was achieved. And for clinical data, the veins were extracted accurately and the structures of veins were displayed clearly.

CONCLUSIONSThe methods can extract veins from the brain susceptibility weighted images exactly and avoid false segmentation of the other structures effectively. The methods are very robust and stable.