Objective To investigate the separation efficiency of three physical separation methods for gaseous ¹⁴C, namely membrane separation, adsorption separation, and low-temperature separation, to screen for the optimal separation method, and to provide a reference for the separation and enrichment of ¹⁴CO₂ in online monitoring of ¹⁴C. Methods The experimental plan was designed, and three devices were constructed for separation and purification experiments. The purity, recovery rate, and separation time of CO₂ separated by the three methods were analyzed. Results All the three methods achieved the separation of CO₂. Under certain conditions, 20 mL of sample gas was obtained. The separation time of membrane separation method was 0.5 hour, CO₂ gas with a sample purity of 0.0486%-0.0488%VOL was obtained, and the recovery rate was only 2.5%−12.7%. The separation time of MOF material adsorption separation method was 24−30 hours, CO₂ gas with a sample purity of 20.2%−47.5%VOL was obtained, and the recovery rate was 57.3%−63.2%. The separation time of low-temperature separation method was 3 hours, CO₂ gas with a sample purity of 96.0%−99.8%VOL was obtained, and the recovery rate was 81.5%−92.5%. Conclusion The purity and recovery rate of CO₂ with low-temperature separation method were higher compared to membrane separation method and MOF material adsorption separation method. The separation time of low-temperature separation method was moderate. The low-temperature separation method can provide a reference for the enrichment technology of ¹⁴C in the rapid measurement of gaseous ¹⁴C effluent.

Objective To establish a method for measurement of ²³⁹Pu in fecal samples based on inductively coupled plasma-mass spectrometry (ICP-MS), and to provide a novel method for assessing the internal exposure of workers. Methods Fecal samples were collected from workers and labeled. The samples were pretreated with carbonization ashing and microwave digestion devices, purified on TEVA resin, and measured using ICP-MS. Results The detection limit of ²³⁹Pu in fecal samples based on ICP-MS was 1.91 × 10⁻⁴ Bq. Conclusion In the routine monitoring of class S substances characterized by a 5 μm aerodynamic diameter during 12 months, the committed effective dose corresponding to the detection limit is 0.17 mSv. This value meets the requirements of relevant national standards and ICP-MS can be used as a novel means for accurate evaluation of internal exposure for workers.

Objective To develop a simplified phantom for the calibration of whole-body counters. Methods A simplified phantom design method for the calibration of whole-body counters was established based on the process and method of calibrating whole-body counters. By using the established method and Monte Carlo method, a simplified phantom including the total body, thyroid, lungs, and gastrointestinal tract was designed to calibrate the ORTEC-Stand FAST II whole-body counter. The simplified phantom was compared with the BOMAB phantom through experimental measurements. Results Within the range of 50 keV to 2 MeV, for rays of the same energy in the same organ of the simplified phantom and BOMAB phantom, the simulated data of detection efficiency by whole-body counting showed an error within 5%, and the experimental measurements showed an error within 10%. Conclusion We developed a simplified phantom for the calibration of the whole-body counter, demonstrating the feasibility of using the simplified phantom instead of a physical body phantom for whole-body counter calibration, which can greatly facilitate whole-body counter calibration for internal radiation monitoring.

Objective To preliminarily study and establish a method for measurement of the transuranic nuclide ²⁴¹Am in fecal samples, and to provide technical support for internal radiation monitoring of staff. Methods Fecal samples were collected with a self-made stool sampler and treated with a self-made carbonization and ashing furnace. DGA resin was used to separate and purify ²⁴¹Am from fecal samples. With ²⁴³Am as the tracer, the orthogonal method was used for condition optimization. Results The optimum conditions for separation and purification were: the acidity of HNO₃ added into the column, 6 mol/L; column flow rate, 0.6 mL/min; and the volume of analytical solution,12 mL. The method based on inductively coupled plasma mass spectrometry showed a detection limit of 9.79×10⁻⁴ Bq for ²⁴¹Am in fecal samples, which was satisfactory and feasible. Conclusion This method fills the vacancy of ²⁴¹Am measurement in fecal samples to some extent, which is of practical significance for internal radiation monitoring and protection for analysts.

Objective:To investigate the correlation between three-dimensional histogram analysis of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)and Gleason score(GS)in prostate cancer(Pca)from two hospital, and its diagnostic efficacy for discriminating low-grade from high-grade Pca.Methods:A total of 102 pathologically confirmed Pca patients in the First Affiliated Hospital of Zhejiang Chinese Medical University and Hangzhou Traditional Chinese Medical Hospital(TCM Hospital)Affiliated to Zhejiang Chinese Medical University from January 2017 to October 2020 were retrospectively analyzed.The quantitative parameters of Pca, including transport constant(K trans), rate constant(K ep), percent volume of the extravascular extracellular space(V e)and fraction of the Intraplasmic contrast volume(V p), were obtained by manually layer by layer delineating of interested regions of all lesions on the original DCE-MRI imaging.Then the three-dimensional histogram analysis of the above parameters were performed to obtain the minimum, maximum, median, mean, area, 10 thpercentile, 25 thpercentile, 75 thpercentile and 90 thpercentile.The correlations between quantitative parameters and GS, and diagnostic efficiencies were analyzed. Results:102 Pca patients were divided into low-grade prostate cancer group(GS≤3+ 4)(n=44)and high-grade Pca group(GS≥4+ 3)(n=58). There were no statistically significant differences in age and location of lesions between the two groups( P>0.05), but there were statistically significant differences in Gleason score, PSA level and lesion diameter between the two groups( U=0.000, 730.000, 711.000, all P<0.05). The median, mean, 10 thpercentile, 25 thpercentile, 75 thpercentile, 90 thpercentile derived from K trans, and K ep(median, mean, 10%, 25%, 75%, 90%)together with maximum of K transand mean for V e were positively correlated with GS( r=0.405 to 0.583, P<0.05), in which mean of K transhad the highest positive correlation( r=0.583, P=0.000). The histogram parameters derived from V pwere negatively correlated with GS( r=-0.301 to 0.341, P<0.05). The area under ROC of 75th percentile derived from K transwas the highest(0.832). When the cut-off value of 75 thpercentile derived from K transwas ≥0.680/min, its Youden index, sensitivity, and specificity were 0.594, 0.776, 0.818, respectively. Conclusions:The three-dimensional histogram of DCE-MRI quantitative parameters has correlation with GS in Pca patients, can be used to discriminate low-grade from high-grade Pca.

Objective: To compare different specimen types of lung adenocarcinoma in the detection of epidermal growth factor receptor (EGFR) gene and to correlate EGFR mutations with patient clinical features. Methods: One hundred lung adenocarcinoma cases were collected from June to December in 2015, at the First Affiliated Hospital of Xinjiang Medical University.Of the 100 lung adenocarcinoma samples, 43 were male and 57 were female. The age was from 40 to 88 years old, and the average age was 66 years. One hundred lung adenocarcinoma cases were divided equally into two groups. Mutation analysis of EGFR gene by real-time PCR was performed using biopsied tissue and paired blood samples in one group (n=50) and using pleural effusion and paired blood samples in the other group (n=50). Results: The mutation rate of EGFR gene in biopsy samples was 54% (27/50) , higher than that of blood samples (46%, 23/50), but without statistical differences (χ²=0.640, P=0.424). In contrast, mutation rate of EGFR gene in pleural effusion samples (42%, 21/50) was higher than that of blood samples (34%, 17/50), but without statistical differences(χ²=0.679, P=0.409). Two patients had EGFR mutation detected in paired blood samples but not in the corresponding biopsy samples, and four patients had EGFR mutation detected in pleural effusion samples but not in their paired blood samples. The mean progression-free survival of patients with detectable EGFR mutation were 9.5 months (tissue samples), 8.6 months (pleural effusion) and 8.5 months (blood). However, there was no statistical difference. Conclusions Blood samples may be used to assess EGFR mutations for patients with lung adenocarcinoma. However, further studies are needed to improve the sensitivity and accuracy in the detection of EGFR mutations using blood samples.

Objective: To investigate the role of PRDM1 gene inactivaion in the regulation of C-MYC in diffuse large B-cell lymphoma (DLBCL), and to explore the correlation of its immunophenotype and prognosis. Methods: 100 cases paraffin-embedded DLBCL tissues were collected from January 2009 to December 2015 at the First Affiliated Hospital of Xinjiang Medical University along with 20 cases of reactive proliferative lymph nodes as control. Immunohistochemical methods were used to detect the expression of CD20, CD10, MUM1, Ki-67, bcl-6, PRDM1/Blimp1, C-MYC and PAX5 protein. The tumors were classified into two subtypes according to Hans classification.The expression of PRDM1 and C-MYC gene in tumor group and control group was detected by reverse transcription PCR (RT-PCR) and the relationship between PRDM1 and C-MYC gene was analyzed.OCI-LY1 (GCB subtype) and OCI-LY3 (non-GCB subtype) cell lines were transfected with small interfering RNA by cationic liposome reagent transfection, and the expression of C-MYC in the transfected cell lines was detected by RT-PCR and Western blot. The Kaplan-Meier method was used to analyze the prognostic significance of PRDM1/Blimp1 and C-MYC at protein and mRNA levels. Results: There were 27 cases of GCB subtype and 73 cases of non-GCB subtype according to Hans classification. The positive expression of Blimp1 in DLBCL group and proliferative lymph nodes in control group was seen in 26(26.0%) and 20 cases(100%), respectively. There were 58 cases with high expression of PRDM1 at mRNA level, including 22 cases of GCB subtype and 36 cases non-GCB subtype, and the difference was statistically significant (P=0.004). There were differences in PRDM1 gene expression between the two immunological subtypes, serum lactate dehydrogenase (serum LDH) level, presence of B symptoms, tumor primary sites and other clinical pathological parameters, while C-MYC expression was different in gender, IPI score, and serum LDH levels. Upon PRDM1/Blimp1 gene silencing in the two cell lines, C-MYC protein and gene expression were up-regulated in the transfection group, compared with the blank control group and negative control group by reverse transcription PCR and Western blot analyses. Moreover, PRDM1 expression was significantly associated with C-MYC(χ²=7.648, P=0.006) at mRNA level. Conclusion The up-regulation of C-MYC gene expression induced by PRDM1 inactivation in DLBCL may play an important role for the development of DLBCL.PRDM1 protein and mRNA are associated with immunophenotyping and PRDM1 mRNA is a marker of poor prognosis.

Objective To evaluate the effect of emulsified isoflurane post-conditioning on the mitochondrial function during lung ischemia-reperfusion (I/R) in rats in an in vitro experiment.Methods Twenty-four SPF healthy male Sprague-Dawley rats,weighing 250-300 g,were used in the study.After the animals were anesthetized,the lungs were removed,connected to the perfusion system and then divided into 4 groups (n=6 each) using a random number table:control group (group C),group I/R,emulsified isoflurane post-conditioning group (group EI) and intralipid post-conditioning group (group IL).After 20 min of equilibration,the lungs were continuously perfused for 105 min in group C,and the lungs were subjected to 45 min ischemia followed by 60 min reperfusion to establish the model of lung I/R injury in the other three groups.During the reperfusion period,the common perfusate was used in group I/R,the perfusate containing 1.68 mmol/L emulsified isoflurane was used in group EI,and the equal volume of perfusate containing 30％ intralipid was used in group IL.At the end of the equilibration (T0),immediately after beginning of reperfusion (T1) and at 30 and 60 min of reperfusion (T2.3),the arterial oxygen partial pressure (PaO2),airway resistance,pulmonary compliance and tidal volume (VT) were recorded.The right upper lobe of the lung was removed at T3 for determination of wet to dry weight ratio (W/D ratio).The right middle lobe of the lung was removed at T3 for pathologic examination with light microscope.The contents of reactive oxygen species (ROS),NAD+ and ATP in lung tissues were detected.Results Compared with group C,the PaO2,pulmonary compliance and Vr were significantly decreased,and the airway resistance was increased at T1-3,and the W/D ratio and ROS content were increased,and NAD+ and ATP contents were decreased at T3 in I/R,EI and IL groups (P＜0.05).Compared with I/R and IL groups,the PaO2,pulmonary compliance and VT were significantly increased,and the airway resistance was decreased at T2.3,and the W/D ratio and ROS content were decreased,and NAD+ and ATP contents were increased at T3 in group EI (P＜0.05).The pathologic changes of lungs were significantly attenuated in group EI as compared with group I/R.Conclusion The mechanism by which emulsified isoflurane post-conditioning attenuates lung I/R injury is related to decrease in mitochondrial dysfunction in rats in an in vitro experiment.

Objective: To investigate the point mutation of epidermal growth factor receptor (EGFR) gene and clinicopathologic characteristics in patients with non-small cell lung cancers(NSCLC)of Xinjiang region. Methods: Five-hundred and eighty-two cases of paraffin-embedded tissue in patients with NSCLC were collected between January 2013 and December 2015 in the First Affiliated Hospital of Xinjiang Medical University. The DNA was extracted from these tissues by Qiagen kit, to test thirty-two mutations in EGFR exons 18, 19, 20 and 21 using fluorescent quantitative qRT-PCR technology by TaqMan probe; the clinicopathologic features of patients were analyzed according to the mutation status of EGFR. Results: There were 173 cases with EGFR gene mutation in 582 cases of paraffin-embedded tissue in patients with NSCLC, and the mutation rate was 29.7%(173/582). There were statistical difference in female patients (50.5%, 98/194), no history of smoking(47.3%, 96/203), high differentiation(6/9), adenosquamous carcinoma(6/11), peripheral location (34.9%, 88/252), and surgical specimens(38.2%, 83/217), respectively (P<0.05). Multiple factors Logistic analysis showed that gender, degree of differentiation, and pathologic types had statistical differences to EGFR when α=0.05. There were no statistical differences between other variants. Conclusions There are higher rate EGFR gene mutation in women patients, non-smokers, and well-differentiated, adenocarcinoma. Gender, degree of differentiation and pathological patterns are independent influencing factors on EGFR mutation status.

Objective To evaluate the role of α2 adrenergic receptors in dexmedetomidine-induced inhibition of lipid peroxidation during lung ischemia-reperfusion (I/R) injury in rats.Methods Thirty-two isolated rat lungs in which the model of isolated lung perfusion was successfully established,were divided into 4 groups (n=8 each) using a random number table:control group (C group),I/R group,dexmedetomidine group (D group) and dexmedetomidine plus yohimbine group (DY group).The isolated lungs were subjected to 60 min of ischemia and apnea followed by 75 min of reperfusion and ventilation to establish the model of isolated lung I/R injury.From the beginning of reperfusion,2.3 ng/ml dexmedetomidine was added to the perfusion fluid in D group,and 2.3 ng/ml dexmedetomidine and 0.4 μg/ml yohimbine (an α2 adrenergic receptor blocker) were added to the perfusion fluid in DY group.Lung specimens were obtained immediately after the end of reperfusion for determination of the wet/dry weight ratio (W/D ratio),superoxide dismutase (SOD) activity (by using modified pyrogallol autoxidation method) and malondialdehyde (MDA) content (by thiobarbituric acid method) and for examination of the pathological changes (using haematoxylin and eosin staining).Results Compared with C group,the W/D ratio and MDA content were significantly increased,and the SOD activity was decreased in I/R,D and DY groups (P＜0.05).Compared with I/R group,the W/D ratio and MDA content were significantly decreased,and the SOD activity was increased in D group (P＜0.05).Compared with DY group,the W/D ratio and MDA content were significantly decreased,and the SOD activity was increased in group D (P＜0.05).The pathological changes of lung tissues were significantly attenuated in D group as compared with I/R and DY groups.Conclusion The mechanism by which dexmedetomidine inhibits lipid peroxidation is related to activating α2 adrenergic receptors during lung I/R injury in rats.