Objective To evaluate the environmental radioactive safety level in China, monitor the radioactivity of strontium-90 (⁹⁰Sr) in seafood from selected marine regions of China, and optimize the di-(2-ethylhexyl)phosphoric acid (HDEHP) extraction chromatography method for determining Sr-90 in seafood. Methods In 2023, seafoods of fish, shrimp, shellfish, and seaweed were collected from the Shandong Province (Bohai Sea and Yellow Sea) and Hainan Province (South China Sea). The levels of Sr in the samples were determined by inductively coupled plasma atomic emission spectrometer (ICP-AES). The ⁹⁰Sr separation were performed using HDEHP extraction chromatography, while the recovery of ⁹⁰Sr were determined by the gravitmetry with the assistant of ICP-AES. Results The content of strontium in seafoods varies greatly, and excessive strontium and calcium in seafood may lead to overestimated recovery due to insufficient leaching during chromatographic separation by HDEHP extraction. Therefore, the yttrium content in the eluent should be analyzed by ICP . The radioactivity of ⁹⁰Sr in seafood from the sea areas in Shandong Province was 0.22-1.85 Bq/kg (dry weight), and that of seafood from Hainan Province was 0.19-1.82 Bq/kg (dry weight). Conclusion For the analysis of shirmp and seaweed samples, the recovery rate of ⁹⁰Sr should be analyzed using both gravimetry and ICP-AES. There is no significant linear correlation between total Sr and ⁹⁰Sr in seafood. There is no significant difference in ⁹⁰Sr radioactivity between the seafood samples collected from Shandong and Hainan. The ⁹⁰Sr radioactivity levels of all 28 samples are below the limit specified in the Limited concentrations of radioactive materials in foods (GB 14882—1994) and are within the range of environmental background fluctuations.

Objective To organize a nationwide interlaboratory comparison for measurement of gross α and gross β radioactivity in water, and improve the laboratory analysis of gross α and gross β radioactivity in water. Methods A unified comparison protocol was developed by the organizers. The groundwater with high natural radioactivity was used as water sample and distributed randomly to the participating laboratories. The participating laboratories used routine analytical methods to measure the samples and provided information such as analytical results, original records, and test reports. The results were evaluated using z-score. Results A total of 76 laboratories participated in the comparison, all employing the evaporation concentration-α/β counting method. Among them, 69 laboratories achieved |z| ≤ 2 for both gross α and gross β radioactivity measurements, and 32 laboratories achieved |z| ≤ 0.50 for both gross α and gross β radioactivity measurements. There were 69 laboratories with qualified results and 30 laboratories with excellent results, yielding a qualified rate of 90.8% and an excellent rate of 39.5%. Seven laboratories showed unqualified results and the unqualified rate was 9.2%. Conclusion Most laboratories have the ability to analyze gross α and gross β radioactivity in water. The main reasons for the deviation in comparison results are calibration efficiency, errors in the total residue mass caused by improper water sample processing operations. By analyzing the main technical problems existed in unqualified laboratories, their ability for measurement of gross α and gross β radioactivity in water has been improved.

Objective To compare the effects of ginsenosides Rg1 and Rb1 on depression-and anxiety-like behaviors in chronic unpredictable stress-induced rats.Methods Seventy male SPF grade SD rats were tested for sugar and water preference after 5 days of adaptation and divided into seven groups according to their preference index:a control group,model group,fluoxetine hydrochloride group,ginsenoside Rg1 24 mg/kg group,ginsenoside Rg1 48 mg/kg group,ginsenoside Rb1 33 mg/kg group,and ginsenoside Rb1 67 mg/kg group.All rats,except for the control group,were subjected randomly to one or two different stimulating factors every day for a total of 35 days.On the 36th day,behavioral experiments including sugar and water preference,open field,novel environment feeding inhibition,elevated cross maze,and forced swimming experiments were conducted to investigate the anti-depression and anti-anxiety effects of the treatments.Serum and hippocampal levels of interleukin(IL)-1β,IL-6,tumor necrosis factor(TNF)-α and serum corticosterone were measured by enzyme-linked immunosorbent assay.Results Compared with the model group,ginsenoside Rg1 and Rb1 significantly increased sucrose consumption in the sucrose preference test and decreased immobility in the forced swimming test.Ginsenoside Rg1(48 mg/kg)significantly reduced the latency to eat in the novelty-suppressed feeding test,and ginsenoside Rg1(24 and 48 mg/kg)significantly increased the percentage of open arm entries and time in the elevated cross maze test.Serum corticosterone levels were significantly decreased in the ginsenoside Rg1 and Rb1 groups,serum IL-1β and IL-6 levels were significantly decreased in the ginsenoside Rg1(48 mg/kg)group,serum TNF-α and IL-6 levels were significantly decreased in the ginsenoside Rb1(33 mg/kg)group,and IL-1β,IL-6,and TNF-α levels in the hippocampus were significantly decreased in the ginsenoside Rg1(48 mg/kg)and Rb1(67 mg/kg)groups.Conclusions Both ginsenosides can regulate the hypothalamic-pituitary-adrenal axis and inhibit neuroinflammation,improving depression-and anxiety-like behaviors in rats induced by chronic unpredictable stress.Ginsenoside Rg1 has a significantly better anti-anxiety effect than Rb1.

Objective:To analyze the indications for invasive prenatal diagnosis in the third trimester and summarize the pregnant outcome.Methods:Clinical data of 121 women who underwent invasive prenatal diagnosis in the third trimester in the prenatal diagnostic center of the First Medical Center of Chinese PLA General Hospital from January 2016 to December 2020 was retrospectively analyzed. Different genetic diagnostic methods were used according to different indications. Indications and results of prenatal diagnosis, as well as the complications within two weeks after the invasive procedure, pregnancy outcome, and neonatal follow-up of all the participants were described.Results:Among the 121 cases, 107 cases underwent amniocentesis, seven underwent percutaneous umbilical blood sampling, and seven had both procedures performed at the same time (one underwent thoracocentesis at the same time). Newly identified ultrasound abnormalities in the second and third trimesters were the main indications for prenatal diagnosis, accounting for 99.2%(120/121), of which short limbs and fetal growth restriction accounted for 25.0% (30/120) and 20.0% (24/120), respectively. Genetic abnormalities and congenital diseases were detected in 20 cases with a detection rate of 16.5%(20/121). Among them, there were nine cases of achondroplasia, five cases of pathogenic copy number variations, one case of achondroplasia with pathogenic copy number variation, one trisomy 18, one 47,XXX, one tetrasome mosaicism of 12p, one de novo WTX c. 1072(Exon2) C>Tp.R358X heterozygous mutation, and one fetal hypoproteinemia. In addition, six cases with copy number variation of unknown significance (VUS) were detected, noting for a detection rate of 5.0%(6/121). Among the 20 cases with abnormal detection, 15 were terminated, two delivered prematurely before obtaining the prenatal diagnosis results, one underwent cesarean section before obtaining prenatal diagnostic results and two continued the pregnancies. In the six cases with VUS, one was terminated and the other five continued the pregnancy. Only one case had preterm premature rupture of membranes 2 d after amniocentesis and the incidence rate of complications after all kinds of invasive procedures was 0.8% (1/121). During the neonatal follow-up, postnatal whole exome sequencing revealed monogenetic disorder in two cases with normal prenatal diagnostic results; the patient with 12p chimerism had developmental delay; the one with WTX mutation deceased on the day of born; the rest newborns developed normally. Conclusions:As a relatively safe method, invasive prenatal diagnosis in the third trimester is of great importance and value in reducing the miss diagnostic rate of fetuses with severe genetic diseases and birth defects. The appropriate application of prenatal whole exome sequencing could further help to decrease the miss diagnostic rate of monogenetic disorder.

Objective:To observe the morphological and hemodynamics changes of aortic segments in mice with angiotensinogen Ⅱ(Ang II) combined with β-aminopropionitrile(BAPN) induced-aortic dissection by color Doppler ultrasound(CDUS).Methods:Twenty male mice of 6-8 weeks old C57BL/6 were randomly divided into two groups: the model group( n=10) was induced by intraperitoneal injection of Ang Ⅱ combined with BAPN to establish mice model with aortic dissection; the control group( n=10) was intraperitoneally injected with normal saline.The body weight, systolic and diastolic blood pressure of the mice were routinely recorded. On the 42th day, CDUS was used to measure the indexes of ascending aorta(AoA), descending thoracic aorta(DAo) and suprarenal aorta(SAo) in both groups, including the inner diameter of the cross section, peak systolic velocity(PSV), the end diastolic velocity(EDV), the resistance index(RI), the pulsatility index(PI), time average mean velocity(TAMV), the heart rate(HR) and the maximal shear rate(SR). Then, the aortas were harvested from the root to the bifurcation of the renal artery. The pathological changes of the aortic wall were observed using hematoxylin-eosin(HE) staining. Results:①There were statistically significant differences in body weight, systolic blood pressure, diastolic blood pressure and heart rate between the model group and the control group(all P<0.05). Compared with the control group(0/10), the incidence of the AoA dissection(8/10) in the model group was obviously higher, the difference was statistically significant( P<0.05); while the incidence of the DAo dissection(4/10) and the SAo dissection(3/10) in the model group was slightly higher, the differences were not statistically significant (all P>0.05). ②Compared with the ascending aorta of the control group, the inner diameter, PSV, EDV, TAMV, PI and SR in the model group were significantly higher(all P<0.05), while RI showed no significant difference between the two groups ( P>0.05). For the descending thoracic aorta, PSV, EDV, TAMV, PI and SR in model group were higher than those of the control group(all P<0.05), however the inner diameter and RI were not significantly different between the two groups (all P>0.05). And for the superior renal aorta, PSV, TAMV, RI, PI and SR in the model group were obviously higher than the control group(all P<0.05), whereas the inner diameter and EDV were not significantly different between the two groups (all P>0.05). ③The HE of the tissue section in the model group showed, the aortas were obviously dilated, irregular, with inhomogeneously thickening wall; the endothelial cell nuclei were slightly stained, and some intima and middle layer ruptured and protruded outward to form dissecting aneurysms. The adventitias were markedly infiltrated with inflammatory cells. Conclusions:Ultrasonography could primarily evaluate the hemodynamic changes of aorta in hypertension with aortic dissection, and the PSV, TAMV, PI and SR of aorta may be important indicators for early predicting the occurrence of aortic dissection in hypertension.

Objective:To achieve rapid and accurate detection of trace uranium in drinking water by analyzing the factors influencing the accuracy of uranium measurement in drinking water using ultraviolet fluorescence method and by evaluating the uncertainty in measurement.Methods:The influence of acidity, Fe 3+ and Mn 2+ contents on the analitical result were studied to optimize the measurement conditions. The accuracy of the measurement method was verified in 7 laboratories. By studying the errors introduced in the process of standard preparation, sample pretreatment and measurement, the sources of uncertainty were analyzed and the uncertainty was synthesized. Results:At pH 1-11 in aqueous solution, the linear regression coefficient of the standard curve was greater than 0.995, which was in line with the linear measurement range of the instrument. At pH 12 or so, the linear regression coefficient was 0.761, which could not meet the measurement requirements. At pH<3 or pH>10, the increase in fluorescence count was lower, which might increase the measurement error. At Fe 3+ concentration ≥15 mg/L, a large deviation occurred in measurement value that could affect seriously measurement result. At Mn 2+ concentration ≥ 1.6 mg/L, the sample produced white precipitation, which could affect the measurement accuracy. Three spiked water samples with different concentrations were determined in 8 laboratories. Each water sample was measured six times in parallel. The relative standard uncertainty of the result were 6.42×10 -2, 4.48×10 -2 and 5.26×10 -2 μg/L, and the expanded uncertainties were 0.03, 0.06 and 0.12 μg/L( k=2), respectively. Conclusions:The optimum conditions for the determination of uranium in water using this method pH were in samples 3-10, the concentration of Fe 3+ less than 15 mg/L, and the concentration of Mn 2+ less than or equal to 1.6 mg/L. The main sources of uncertainty in the measurement of uranium in water using ultraviolet fluorescence method arise from the repeated measurement error and the volume of added standard solution.

Objective:To study the influence of source thickness and counting efficiency calibration on the measurement of gross alpha activity in water.Methods:241Am and natural uranium reference materials were spiked in drinking water to prepare source on a planchet with different thickness, for counting alpha activity on the planchet. Results:The effective thickness measured by spiking 241Am or uranium standard solution in water sample was consistent with the empirical value of 4 mg/cm 2. The alpha counting rate was in a linear increase trend from 2A-5A mg/cm 2 and was basically stable and no longer increase when thickness was higher than 10A mg/cm 2 (A was area of planchet). The result calculated by effective thickness method and thick source method were in good agreement when thickness was 10A mg/cm 2. Conclusions:In order to reduce the deviation of gross alpha counting rate caused by the source thickness and counting efficiency calibration, the source thickness is recommended to be 10A mg/cm 2.

Objective:To explore the clinical value of point-of-care ultrasonography(PoCUS) in the diagnosis of acute pulmonary embolism(PE).Methods:Consecutive 196 patients suspected of acute PE were enrolled in East Branch, the Second Hospital of Hebei Medical University from January 2017 to November 2017. All the patients were categorized into no PE group( n=143) and PE group( n=53) based on CTPA results. PoCUS was performed and considered diagnostic for PE if one or more right ventricular dysfunction (right ventricular dilation, right ventricular free wall hypokinesia, increased tricuspid regurgitation velocity or decreased tricuspid annular plane systolic excursion), deep venous thrombosis(DVT) or subpleural infarcts were detected. Results:With CTPA as the gold standard for diagnosis, the sensitivity (94.34%), Youden index (0.531) and the area under the ROC curve(AUC) (0.765) of the combined diagnosis of PE by transthoracic echocardiography(TTE), lower limb vein compression ultrasonography(CUS) and lung ultrasonography (LUS) were the highest. The specificity (94.41%) and accuracy (81.63%) of LUS in the diagnosis of PE were the highest, and the misdiagnosis rate (5.59%) of LUS the lowest. The sensitivity of the combined triple PoCUS (TTE, CUS, and LUS) diagnosis of PE was higher than TTE and CUS combined diagnosis ( P=0.016), and the sensitivity and specificity were higher than TTE and CUS combined diagnosis as a whole ( P<0.005). Conclusions:The combined triple PoCUS (TTE, CUS, and LUS) has the highest accuracy in the diagnosis of PE, while LUS has a high specificity and a low misdiagnosis rate in the diagnosis of PE. Therefore, it is recommended to apply the combined triple PoCUS in clinical practice.

Objective To investigate pathogenic genes related to the phenotype of fetus with severely short limbs in the first and second trimester by whole exome sequencing (WES). Methods Thirteen fetuses with severely short limbs detected by ultrasonography in the first and second trimester admitted in Chinese PLA General Hospital from September 2016 to June 2018 were collected. All cases were performed induced abortion, 6 of which were carried out karyotype analysis of amniotic fluid at the same time. WES and copy number variations (CNV) were performed on specimens from fetal tissues after labor induction. The suspected pathogenic mutations were validated by Sanger sequencing reactions. Results No abnormal karyotypes or pathological CNV were found. In 10 fetuses, pathogenic or possibly pathogenic mutations were detected in the following genes: COL2A1, FGFR3, COL1A1, COL1A2, DYNC2LI1 and TRIP11, all of which were essential to skeletal development. The diagnostic yield of WES in the fetuses with severe short limbs was 10/13. Conclusions In the first and second trimester, most of the fetuses with extremely short limbs suffer from monogenic diseases. WES is likely to be a valuable diagnostic testing option for the fetuses with severe short limbs.

Objective To observe the features of temporal macular thinning and its value for the diagnosis of Alport syndrome (AS) in young patients.Methods Eighty-one young patients with AS (81 eyes) from Peking University First Hospital during January 2016 and July 2017 were included in this study.There were 67 males (67 eyes) and 14 females (14 eyes),the aged from 3 to 17 years,with the mean age of 9.6 years.Among 81 patients (81 eyes),there were 64 patients with X-linked AS (XLAS,including 53 males and 11 females),17 patients with autosomal recessive AS (ARAS,including 14 males and 3 females).One hundred healthy subjects aged 4 to 17 years were included as controls.Clinical data were retrospectively evaluated,including visual acuity,slit-lamp microscopy,dilated fundus photography,and OCT.Retinal thickness was measured with an OCT scan and the temporal thinning index (TTI) was calculated as stated in a previous study.The TTI values of each group was compared by One-way ANOVA or independent sample t test.The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic effectiveness for AS.Results The TTI of the control group,XLAS and ARAS patients were 6.46 ± 1.58,10.93 ± 3.77,12.14± 4.05,respectively.Compared with the control group,the TTI value of males were larger in the XLAS and ARAS group (F=45.056,P＜0.001),the TTI value of females were larger in the ARAS group (F=26.541,P＜0.001).The difference of TTI value in females was significant between the XLAS and ARAS groups (F=26.541,P＜0.001).In males,the area under the ROC curve was 0.896 (95％CI 0.837-0.955,P＜0.001).The optimal cutoff value of the TTI was determined as 9.47,with a sensitivity of 73.1％ and a specificity of 100％.Conclusions TTI is a common ocular finding in young patients with AS.In males,a TTI ＞ 9.47 may differentiate AS from normal males.