1.Clinical applications of contrast-enhanced ultrasound.
Acta Academiae Medicinae Sinicae 2008;30(1):1-4
Microbubble contrast agents for ultrasound (US) have been developed and clinically applied in recent years. Contrast-enhanced ultrasound (CEUS) has been widely used in the imaging of liver and other organs such as kidney, pancreases, spleen, prostate, ovarian, uterus as well as abdominal trauma, showing promising values in the diagnosis and differential diagnosis of various diseases. This article reviews the recent development and future protential clinical applications of CEUS.
Contrast Media
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administration & dosage
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Diagnosis, Differential
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Drug Delivery Systems
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Humans
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Microbubbles
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Ultrasonography
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methods
2.EFFECTS OF ANGIOTENSIN Ⅱ AND ALDOSTERONE ON COLLAGEN METABOLISM OF CULTURED CARDIAC FIBROBLASTS
Xin DU ; Guizhu DAI ; Zongchen FENG
Medical Journal of Chinese People's Liberation Army 2001;26(1):64-66
To explore the influence of angiotensinⅡ(AngⅡ) and aldosterone (Ald) on synthesis of collagen and activity of precollagenase secreted by cardiac fibroblasts.Sirus Red method was employed to evaluate collagen synthesis of cultured cardiac fibroblasts; typeⅠ collagen was measured by competitive ELISA; collagenase activity was tested by fluorescence spectrophotometry.At the doses of 10-9~10-7mol/L, AngⅡ could enhance gross and typeⅠ collagen production in a dose-dependent manner. Collagenase activity decreased with increasing concentration of AngⅡ. These effects of AngⅡcould be completely abolished by its receptor antagonist, saralasin. Ald might enhance gross and typeⅠ collagen production only at a higher concentration (10-7~10-8mol/L), whereas lower concentration (10-9mol/L) had no effect on it. These effects of Ald could be abolished by spironolactone,a specific Ald receptor antagonist. In addition, Ald could significantly decrease the activity of collagenase secreted from cultured cardiac fiboblasts at concentrations of 10-9~10-7mol/L within 24h,which could not be antagonized by 10-6mol/L spironolactone. The results suggested that AngⅡand Ald enhance cardiac fibroblasts collagen synthesis and inhibit collagenase activity ,resulting in net collagen accumulation resulted and acceleration of cardiac fibrosis.
4.The role of arginase in the airway inflammation and airway remodeling
Wei DAI ; Jie WU ; Xiaofeng XIN
Journal of Medical Postgraduates 2015;(2):221-224
Bronchial asthma is the chronic airway inflammatory disease that characterized by reversible airflow limitation .The presence of airway inflammation could lead to airway remodeling .In recent years , many studies have found that arginase plays an im-portant role in the airway inflammation and airway remodeling of asthma .It not only reduces airway release nitric oxide and increases airway hyperresponsiveness , but also its metabolites such as putrescine , proline, etc can induce cell proliferation and collagen synthe-sis, leading to airway remodeling .In this paper , the arginase and its role in the pathogenesis of asthma are discussed .
5.Color stability of carious incipient lesions in the enamel treated with resin infiltration
Xin LI ; Ping GAO ; Xiaohua DAI
Chinese Journal of Tissue Engineering Research 2015;(38):6161-6166
BACKGROUND:The resin infiltration technique for masking white spot lesions has obtained a result superior to the conventional remineralization. Up to now, few studies have evaluated the color of carious incipient lesions treated with the resin infiltration.
OBJECTIVE:To assess the color change of caries incipient lesions in the enamel treated with resin infiltration.
METHODS: Forty-eight extracted teeth were exposed to demineralizing solution for 4 weeks to establish artificial caries models. Then artificial caries models were treated with resin infiltration and randomized into four groups: these specimens were immersed in red wine, coffee, tea and artificial saliva for 2 and 4 weeks, respectively. The base line color was evaluated by spectrophotometer. The variation in color (ΔE) was analyzed by one-way analysis of variance and Tukey’s tests.
RESULTS AND CONCLUSION:Al specimens underwent color and lightness changes, irrespective of immersion media. After 2 weeks of immersion, ΔE values were ranked as folows: red wine > coffee > tea > artificial saliva, and there were significant differences between four groups (P < 0.05). After 4 weeks of immersion,ΔE values were ranked as folows: red wine≈ coffee > tea > artificial saliva, and there were significant differences between four groups (P < 0.05) but not between the red wine and coffee groups (P > 0.05). Significant changes in the color were found in the red wine and coffee groups at different time after immersion (P < 0.05). Immersed in red wine, coffee and tea, the?E value was > 3.7, which is not acceptable in clinic. These findings indicate that the color stability of carious incipient lesions located in the enamel treated with resin infiltration is associated with the soak solution and soak time. In addition, immersion in red wine and coffee results in significantly increased color alteration (ΔE) compared with the artificial saliva.
6.Mechanical properties of N48 type orthodontic NdFeB magnet
Zhiming HOU ; Ming XUE ; Xin DAI
Journal of Practical Stomatology 2001;0(03):-
Objective: To test the mechanical properties o f N48 NdFeB magnet.Methods:Samples of N48 NdFeB magnet in the size of 2 mm?3 mm?4 mm were prepared, the residual flux density,coercive force and maximum energy product of the samples were measured, the magnetic density aroun d the magnets,the attractive and repulsive force between two magnets in 0~10 mm air gap were investegated.Results:The residual flux density of t he N48 NdFeB magnet was 1.373 T, coercive force 1 037 A/m and maximum energ y product 368 kJ/m 3.The magnetic density at magnet surface was 0.338 T,it decr eased to 0 at the point that leave magnet surface 20 mm away. The highest attrac tive force was 4.47 N between two magnets, the attractive force was 4.47~0.39 N in 0~5 mm air gap.The highest repulsive force was 2.82 N and the repulsive force was 2.82~0.39 N in 0~5 mm air gap.Conclusion:The magnetic and m echanical properties of the N48 NdFeB magnet can meet the standard of the orthod ontic force.
8.Effect of Cognition Training on Aphasia after Stroke
Xin DAI ; Jilai LI ; Jichen DU
Chinese Journal of Rehabilitation Theory and Practice 2011;17(1):66-67
ObjectiveTo study the effect of the cognition training on aphasia after stroke. Methods60 patients with aphasia and cognition functional impairment after stroke were divided into 2 groups. The control group received comprehensive treatment, including speech therapy, while the treatment group accepted cognitive functional training in addition. They were assessed with the Loewenstein Occupational Therapy Cognitive Assessment Battery (LOTCA) and China Rehabilitation Research Center Aphasia Examination (CRRCAE) before and after training. ResultsThe scores of LOTCA (P<0.05) and the CRRCAE (P<0.0001) improved in treatment group compared with the control group after training. ConclusionThe cognition functional training above the aphasia functional training facilitates the recovery of aphasia in patients with aphasia and cognition disorder after stroke.
10.Analysis of the factors effecting the expression efficiency of the green fluorescent protein gene in mouse embryonic stem cells
Hua YANG ; Jian-Xin DAI ; Xu-Ming DAI ; Ji-Liang FU
Academic Journal of Second Military Medical University 2001;22(4):319-321
Objective: To study the factors effecting the expression of the reporter green fluorescent protein (GFP) gene in the mouse embryo stem cell line R1. Methods: Three different kinds of GFP euko-expression vectors were constructed, and the expression efficiency was contrasted both at mRNA and protein levels after they were integrated into the chromosomes of host cells. Results: At protein level, the GFP expression level of the colonies transfected by the expression vector-pEF-GFP with the promoter of the peptide elongation factor (EF) were significantly higher than that of the colonies transfected by pCMV-GFP with CMV promoter and by pdCMV-GFP with double copies of CMV-GFP expression unit. There was no significant difference between the colonies transfected by pCMV-GFP and pdCMV-GFP. The detection results on mRNA level of GFP had the same tendency as that at protein level. Conclusion: (1) GFP gene expression efficiency controlled by EF promoter is distinctly higher than that by CMV promoter in NIH3T3 and R1 ES cell line.(2) A slight increase of the copy number of the foreign gene expression units in the host chromosome can not make obvious increase of its expression efficiency. (3) The vector express GFP in R1 ES cell line efficiently and stablely is obtained.