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Radiation safety has been a focus of attention in the past few years. This review summarizes the researches related to the effective dose (ED) of PET/CT in recent years, including the ranges and influential factors of ED. In order to provide guidance in clinical practice, the common methods for estimating ED of PET/CT are also introduced.
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Objective To prepare PET molecular probe folate-NOTA-Al18F(18F-FNA) and to explore its feasibility as an imaging agent in folate receptor positive KB tumor.Methods 18F-FNA was prepared by the method of aluminum fluoride coordination labeling, and the effect of phase transfer catalyst K2.2.2 on the labeling yield was evaluated.Biological distribution was carried out at 10, 30 and 90 min after injection of 3.7 MBq 18F-FNA in nude mice (n=20) xenografted with KB tumor, and the radioactive uptake (%ID/g) and T/NT ratios were then calculated in different organs or tissues.MicroPET imaging was performed at 40 min after injection of 18F-FNA (3.7 MBq).Results The labeling yield of 18F-FNA increased with the presence of K2.2.2.The radiochemical yield was above 98%.The radiochemical purity was above 99%, and still above 98% after maintained in PBS and FBS at 37 ℃ for 4 h.The biodistribution showed that the blood clearance of the probe was slow, and the uptakes in kidneys and tumor which overexpressed folate receptor were significantly high ((5.12±0.58) %ID/g and (1.37±0.20) %ID/g).The high radioactive uptake was observed in KB xenografted mice using microPET imaging.Conclusions The labeling yield of 18F-FNA could increase with the presence of K2.2.2.Furthermore, the encouraging biological distribution and microPET imaging results indicate that 18F-FNA may be a candidate for PET imaging in targeting folate receptor.
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Objective·To investigate and compare the clinical characteristic of non-organic dyspnea and asthma both with complaint of dyspnea.Methods·Seventy-four consecutive patients with non-organic dyspnea,and 74 age-,height-,weight and sex-matched patients with asthma were recruited for investigation in the study.The self-assessment surveys were conducted for the two groups by means of Hospital Anxiety and Depression Scale,Nijmegen Questionnaire and Athens Insomnia Scale.The words for describing dyspnea,clinical symptoms,effective sleep hours and items of pulmonary function test were collected and analyzed Results·Non-organic dyspnea patients tended to describe psychogenic aspects.Asthma patients tended to describe airflow limitation.Non-organic dyspnea group mainly performed psychogenic symptoms.The sleeping time in non-organic dyspnea group was significantly lower than that in asthma group(P＜0.05).The score of anxiety,depression,Nijmegen Questionnaire,Athens Insomnia Scale,FEV1,FEV1％Pred,FVC％Pred,FEV1/FVC in non-organic dyspnea group were significantly higher than those in asthma group (P＜0.05).There was no significant difference in FVC between two groups(P＞0.05).Conclusion·The non-organic group feel more anxiety,depressed and insomnic than the asthma group.Lung function test of asthma group is often abnormal.To discriminate non-organic dyspnea with asthma,clinicians should pay more attention to emotion,sleep,somatoform symptoms,medical history and so on,and do pulmonary function test,improve the understanding of the characteristics of the two diseases,decrease misdiagnosis and wrong diagnosis.
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To investigate the biological characteristics of mycobacteriophage Leo and its bactericidal effect on Mycobacterium tuberculosis for cocktail therapy ,we observed mycobacteriophage plaques after amplifying phage by double‐layer agar plate method .The morphological characteristics were observed by electron microscopy .Mycobacteriophage Leo DNA was extracted and then digested by restriction enzyme to identify the nucleic acid type .Leo was amplified in different multiplicity of infection (MOI) to find the optimal MOI and the minimum MOI .One step growth experiment was carried out to find the latent period and burst size of Leo .The frequency of Mycobacterium smegmatis mutation treated with mycobacteriophage Leo was inspected by the endpoint titration test .The effect of temperature and alcohol on Leo survival was surveyed .The ability of Leo to crack host bacteria at different pH values was examined .The effect of Leo on Mycobacterium tuberculosis was determined by bacteri‐cidal assay .Results showed that the Leo plaque was round and transparent with a diameter of 1 .5 nm .Leo has an isometric head (70 ± 3 .0 nm in diameter) and a flexible tail (211 ± 31 .7 nm in length) .Its genome could be digested by restriction en‐zyme of Hind Ⅲ and Bgl Ⅰ .The optimal MOI and the minimum MOI of Leo were 0 .000 01 and 0 .000 1 ,respectively .The mutation frequency was 10-7 .The latent period was 150 min ,and the burst size was 74 .Leo could not only crack host bacteria in solid medium at pH 7 .4 but also at pH 5 .0 .After 72 hours ,the amount of Mycobacterium tuberculosis in Leo group was less than that in control group (P<0 .05) .In conclusion ,Leo has a bactericidal effect on Mycobacterium tuberculosis and could be a candidate of phage cocktails .
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This study was aimed to analyze the value of the SPECT MPI to myocardial ischemia and cardiac function parameters in the CAD prognosis assessment. A total of 890 patients with suspected CAD underwent adenosine loading stress gated SPECT. At a mean follow-up of (2.3 +/- 0. 4) year, a total of 37 adverse events occurred, including 12 cardiac deaths and 25 nonfatal myocardial infarctions. Univariate Cox analysis showed that diabetes (wald 6.95, P < 0.01), SSS (wald 24.31, P < 0.001), EF (wald 17.14, P < 0.001), ESV (wald 8.58, P < 0.01) and EDV (wald 7.95, P < 0.01) were significant predictors of MACEs. Multivariate Cox analysis showed that SSS (wald 6.69, P < 0.05) and EF (wald 4.70, P < 0.05) were independent predictors. According to the results, SSS and EF are both independent predictors of MACEs.
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Aged , Female , Humans , Male , Middle Aged , Adenosine , Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography , Methods , Coronary Disease , Diagnostic Imaging , Prognosis , Tomography, Emission-Computed, Single-Photon , Methods , Ventricular Function, Left , PhysiologyABSTRACT
Objective To observe the serum levels of high mobility group box-1 protein (HMGB1)in patients with acute cholangitis (AC) and to investigate contributions of HMGB1 in AC.Methods Serum HMGB1 concentrations were determined by an enzyme-linked immunosorbent assay in 30 patients with AC of severe type (ACST) and 42 patients with mild acute cholangitis at the time of admission (within 72 h after the onset).A total of 50 healthy subjects were recruited as the control group.Fluorescent quantitative PCR (FQPCR) was used to detect the HMGB1 mRNA expression and the relationship between serum HMGB1 levels and clinical factors was analyzed.Results The serum HMGB1 levels in healthy control group,mild group and ACST group were (1.82 ± 0.64) μg/L,(10.46 ± 3.75) μg/L,(18.89 ± 6.86) μg/L,respectively.The mean value of serum HMGB1 level in mild group was significantly higher than that in control group,while significantly lower than that in ACST group (P ＜ 0.05).Compared to the control group,the HMGB1 mRNA level in patients of AC increased significantly and the level of ACST group was higher than that of mild group.The serum HMGB1 levels of patients with positive bile or/and blood cultures were higher than that of negative.After emergency endoscopic nasal biliary drainage,the serum HMGB1 levels of patients significantly decreased compared to preoperational (P ＜ 0.05).The HMGB1 levels were significantly positively correlated with white cell counts,C-reactive protein (CRP),total serum bilirubin,direct bilirubin and alkaline phosphatase (ALP).By logistic regression analysis,serum HMGB1 levels had correlation with severity of disease.Conclusion Serum HMGB1 levels significantly increased in patients with AC and the serum concentrations of ACST group were higher than those of mild group.Serum HMGB1 level has a correlation with sepsis.ENBD could lower its serum levels.Serum HMGB1 has predictive value to severity of disease.
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In the present study, the accuracy of the 4-dimensional model single photon emission computed tomography (4D-MSPECT) and quantitative gated single photon emission computed tomography (QGS) was investigated for assessing left ventricular end-diastolic (EDV), end-systolic volume (ESV) and ejection fraction (EF) from gated myocardial perfusion imaging (G-MPI) using left ventriculography (LVG) as reference. From December 2008 to June 2011, 85 patients, who underwent rest G-MPI and LVG (within 30 days) in West China Hospital, Sichuan University, were retrospectively recruited. EDV, ESV, and EF were calculated from G-MPI using 4D-MSPECT and QGS. Eighty-five patients (47 men, 38 women; age 57 +/- 13 years) were finally analyzed. Correlation between results of G-MPI and LVG was high for EDV, r = 0.89 (4D-MSPECT), r = 0.81 (QGS); ESV, r = 0.97 (4D-MSPECT), R = 0.95(QGS); EF, r = 0.95 (4D-MSPECT), r = 0.93 (QGS). 4D-MSPECT and QGS underestimated EDV significantly compared with LVG [(125 +/- 20) mL (4D-MSPECT), (118 +/- 39) mL (QGS), (131 +/- 33)mL (LVG)]. The ESV, 4D-MSPECT and QGS values did not differ significantly from LVG [(47 +/- 32) mL (4D-MSPECT), (53 +/- 29) mL (QGS), (49 +/- 37) mI (LVG)]. For LVEF, only QGS yielded values were significantly lower than LVG [61% +/- 21% (4D-MSPECT), 55% +/- 17% (QGS), and 63% +/- 19% (LVG)]. EDV, ESV, and EF as determined by 4D-MSPECT and QGS from G-MPI agree well with relevant values with LVG. However, Algorithm-inherent also showed slightly over- or under-estimation of volumes. Therefore, separated normal databases should be set up for each algorithm.
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Aged , Female , Humans , Male , Middle Aged , Algorithms , China , Myocardial Perfusion Imaging , Regression Analysis , Software , Tomography, Emission-Computed, Single-Photon , Ventricular Function, LeftABSTRACT
This paper is aimed to investigate the influence of gated myocardial perfusion imaging (G-MPI) with 8- and 16-frame acquisition models on the assessment of left ventricular function. Patients prepared for stress and rest G-MPI were prospectively recruited from January 2010 to January 2011 in the Department of Nuclear Medicine of West China Hospital, Sichuan University. Two separate G-MPI studies, one with 8 and the other with 16 frames, were simultaneously acquired during a single gantry orbit using Concurrent Imaging technique. We calculated the left ventricular ejection fraction (EF) and volumes using the Auto Quant software. Forty-eight patients (29 men, 19 women; average age 51 +/- 16 years old) were finally analyzed. The differences in left ventricular EF between 8- and 16-frame were small: 3.27% (95% CI: 6.41%-0.12%) for post-stress and 3.13% (95% CI: 5.93%-0.32%) for rest. Both using 8 and 16 frames, there were significantly larger volumes and lower EF in patients with stress-induced ischemia than without. As for detecting left ventricular EF, 8-frame and 16-frame acquisition models should not be mutually alternated.