Objective To evaluate the role of distortion product otoacoustic emissions (DPOAE) testing in evaluating early hearing loss among noise-exposed workers. Methods A total of 174 noise-exposed workers in a metal shipbuilding enterprise were selected as the research subjects by the convenience sampling method. Pure tone audiometry (PTA), DPOAE and the level of noise exposure were conducted on the workers. The rank correlation analysis was used to analyze the correlation between DPOAE amplitude and PTA threshold. The multilevel model was used to analyze the effects of gender, age, noise exposure intensity, cumulative noise exposure (CNE), hearing loss classification and PTA threshold on DPOAE results. Results At the frequencies of 0.50, 1.00, 2.00, 3.00, 4.00, 6.00 and 8.00 kHz, the DPOAE amplitude was negatively correlated with the PTA threshold (rank correlation coefficients were -0.12, -0.48, -0.47, -0.18, -0.23, -0.44, -0.19, respectively, all P<0.01). At the most frequencies, DPOAE amplitude was negatively correlated with age and CNE (all P<0.05). The results of multilevel model analysis showed that there were significant differences in DPOAE amplitudes at certain frequencies across gender, age, noise intensity, CNE, and hearing loss classification (all P<0.05). Significant differences in DPOAE responses were found among different CNE and hearing loss groups (all P<0.01). Conclusion DPOAE testing can objectively reflect the hearing status of noise-exposed workers and could be considered for inclusion in routine hearing monitoring to facilitate early detection of noise-induced hearing loss.

Objective:To analyze the difference and reliability of blood 17-hydroxyprogesterone (17-OHP), an indirect screening index for congenital adrenal hyperplasia (CAH), between preterm and full-term infants.Methods:In this retrospective cross-sectional study, a total of 210 285 newborns who underwent CAH screening at the Neonatal Screening Center of Shanghai Children′s Hospital from January 2019 to December 2022 were collected, including 14 312 premature infants and 195 973 full-term infants.The concentration of 17-OHP in dried blood spots on filter paper was determined by an automatic fluorescence analyzer.The distribution of 17-OHP levels in preterm and full-term infants and its statistical index were analyzed.The Kolmogorov-Smirnov test was used for normal distribution.The skewed distribution data was converted into approximately normal distribution using Box-Cox.Outliers were eliminated by the interquartile range method.The cumulative frequency distribution map was drawn by R language programming.The 99.5 th percentile value was used as the screening threshold and compared with the reference value given by the manufacturer or laboratory and with the reference change value (RCV). Results:According to the threshold provided by the laboratory, 26.76‰ of premature infants were tested positive in preliminary screening, and 4 were confirmed with an incidence of 1∶3 578, while 0.79‰ of full-term infants were tested positive in preliminary screening, and 11 were confirmed with an incidence of 1∶17 816.The thresholds for CAH screening established indirectly were 20.35 nmol/L in preterm infants and 10.78 nmol/L in full-term infants.The relative deviations between the indirect CAH screening thresholds and the manufacturer′s or laboratory′s CAH screening thresholds were higher than the RCV, respectively.According to the indirect CAH screening thresholds, the negative and positive coincidence rates of 65 samples in 13 batches from the Centers for Disease Control and Prevention interlaboratory quality assessment program in the United States reached 100%.A retrospective analysis of 210 285 neonates showed that 17-OHP concentration was higher than the screening threshold in all CAH-positive neonates.The application of this screening threshold reduced the false positive rate of preterm infants by 59.79%.Conclusions:It is feasible to establish the CAH screening thresholds for premature and full-term infants by an indirect method, which can improve the efficiency of screening and provide better diagnostic basis for clinical practice.

Liver transplantation is an effective treatment of end-stage liver diseases. However, liver ischemia-reperfusion injury (IRI) and rejection significantly cause the decrease of survival rate of liver graft. Therefore, it is urgent to explore a novel method, which can not only alleviate liver IRI, but also promote immune tolerance of allograft, thereby improving the survival rate of liver graft. Extracellular vesicle (EV) is nanoparticle released from cells into the extracellular microenvironment, which may alleviate graft injury by repairing autophagy, immunosuppression and accelerating tissue regeneration. Hence, EV becomes a research hot spot in the field of liver transplantation. Nevertheless, the clinical application of EV encounters multiple challenges, such as separation, purification, identification, storage of EV and how to deliver EV to the target cells. In this article, the mechanism of EV in liver IRI, the challenges in clinical application of EV and the potential application of EV were reviewed, aiming to provide reference for the clinical application of EV in liver transplantation.

Objective:To improve the quality of 18F-fluorodeoxyglucose (FDG) PET images at different acquisition times through deep learning (DL) PET image reconstruction methods. Methods:A total of 45 patients (20 males, 25 females; age (52.0±13.6) years) with malignant tumors and PET/CT scans from September 2020 to October 2020 in the Department of Nuclear Medicine of the First Hospital of Shanxi Medical University were included in this retrospective study. The short acquisition time 30 s/bed PET images from the raw list mode were selected as the input of DL model. DL image reconstruction model, based on the Unet algorithm, was trained to output imitated PET images with full dose standard acquisition time (3 min). The image quality evaluation and quantitative analysis were carried out for four groups of images: DL images, 30 s, 90 s, and 120 s images, respectively. The quality of PET images in four groups was evaluated using the five-point method. Liver background activities, lesions quantification parameters (maximum standardized uptake value (SUV max), mean standardized uptake value (SUV mean), standard deviation (SD), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR)), and first-order texture features (skewness, kurtosis, uniformity, entropy) were measured. Kappa test, χ2 test and one-way analysis of variance (least significant difference t test) were used for data analysis. Results:The image quality scores between four groups were highly consistent ( Kappa=0.799, P<0.001). The number of patients with scores≥3 in DL, 30 s, 90 s and 120 s groups were 6, 4, 7 and 8, respectively ( χ2=125.47, P<0.001). The liver SD of DL group was significantly lower than that of 30 s group (0.26±0.07 vs 0.43±0.11; F=3.58, t=-7.91, P<0.05). The liver SNR of DL group was higher than that of 30 s group (11.04±4.36 vs 5.41±1.41; F=10.22, t=5.40, P<0.05). The liver SD and SNR of DL group were similar to those of 90 s group (0.39±0.16, 8.46±3.34; t values: -0.87 and 2.17, both P>0.05). In 18 tumor lesions with high uptake, SNR and CNR of DL group were significantly higher than those of 30 s group (60.21±29.26 vs 38.38±16.54, 22.26±15.85 vs 15.41±9.51; F values: 13.09 and 7.05; t values: 5.20 and 4.04, both P<0.001). There were statistically significant differences among four groups in the first-order texture features ( F values: 4.30-9.65, all P<0.05), but there was no significant difference between DL group and 120 s group ( t values: from -1.25 to 0.15, all P>0.05). Conclusion:DL reconstruction model can improve the quality of short-frame PET images, which meets the needs of clinical diagnosis, efficacy evaluation and radiomics research.

Retrospective cohort study.

Retrospective cohort study.

Objective:To compare four reconstruction algorithms of 18F-fluorodeoxyglucose (FDG) PET/CT on standardized uptake value (SUV) of pulmonary nodules. Methods:A total of 46 patients (27 males, 19 females; median age: 66 (range: 44-82) years) with solid pulmonary nodules from February 2018 to July 2019 in the First Hospital of Shanxi Medical University who performed 18F-FDG PET/CT imaging were enrolled. All PET/CT images were retrospectively reconstructed by using four algorithms reconstructions including ordered subset expectation maximization (OSEM), OSEM+ time of flight (TOF), OSEM+ TOF+ point spread function (PSF) and block sequential regularized expectation maximization (BSREM) (G1-G4). Nodule and background parameters were analyzed semi-quantitatively and visually. The maximum of SUV(SUV max), mean of SUV(SUV mean) and peak of SUV (SUV peak) were collected by the region of interest (ROI). Nodules were divided into small nodule group (diameter ≤10 mm) and large nodule group (10 mm < diameter ≤30 mm). Kruskal-Wallis rank sum test and Bonferroni method were performed to compare the differences of SUVs between G1-G4, and Spearman correlation analysis was used to analyze the correlation between the change rate of SUV (%ΔSUV) and the diameter of nodules. The receiver operating characteristic (ROC) curve analysis was used to analyze the diagnostic efficacy of SUV for the differential diagnosis of pulmonary nodules and to get the optimal threshold. Results:There were 114 pulmonary nodules (large nodules, n=55; small nodules, n=59). In visual analysis, the visual detection rates of small nodules in G4 were 55.93%(33/59), 44.07%(26/59), 20.34%(12/59) higher than those in G1-G3. Of 114 pulmonary nodules in 46 patients, there were differences in SUV max and SUV mean between G1-G4 (median SUV max : 2.65-5.29, median SUV mean: 2.05-2.99; H values: 20.628 and 17.749, respectively, both P<0.001), G4 had significant increases compared to G1 in SUV max (median 5.29 and 2.65, P<0.001) and SUV mean (median 2.99 and 2.05, P<0.001). The %ΔSUV max (median: 4.45%-52.96%) and %ΔSUV mean (median: 1.69%-47.56%) were negatively correlated with the diameter of nodules (9.75(6.20, 16.58) mm; r s values: -0.371 to -0.354, -0.371 to -0.320, all P<0.001). In 59 small nodules, G1 significantly increased the SUV max of G4 (median 4.05 and 2.14, H=18.327, P<0.001), while G4 significantly increased the SUV mean of G1 and G3 (median 2.31, 1.26 and 1.53, H=16.808, P<0.05). There was no significant difference in SUVs between G1-G4 in 55 large nodules ( H values: 0.812-7.290, all P>0.05). The optimal threshold values of SUV max in G1-G4 were 4.335, 5.185, 5.410, 5.745 and the area of under curves (AUCs) were 0.747, 0.699, 0.756, 0.778 respectively. The AUC of SUV mean and SUV peak also showed a similar trend. Conclusion:Among the four reconstruction algorithms, BRERM can not only enhance the image quality, but also significantly improve the SUV max and SUV mean of lung nodules diameter below 10 mm, and thus its diagnostic threshold of SUV should be appropriately increased.

Objective:To compare the incidence of coronary microvascular disease (CMVD) between patients with non-obstructive and obstructive coronary arteries.Methods:We retrospectively analyzed 97 patients with angina pectoris, who underwent the absolute quantitative PET examination of myocardial perfusion and coronary anatomy examination within 90 days. All patients were divided into two groups: non-obstructive group (72 cases, no stenosis ≥50% in all three coronary arteries) and obstructive group (25 cases, at least one coronary stenosis ≥50%; and at least one coronary stenosis<50%). Quantitative parameters derived from PET including rest myocardial blood flow (RMBF), stress myocardial blood flow (SMBF), coronary flow reserve (CFR) and cardiovascular risk factors were compared between the two groups. CMVD was defined as CFR<2.90 and SMBF <2.17 ml·min -1·g -1. Results:Incidence of CMVD was significant higher in the non-obstructive coronary arteries of the obstructive group than in the non-obstructive coronary arteries of non-obstructive group (47.1% (16/34) vs. 25.5% (55/216), χ 2=6.738, P=0.009) while incidence of CMVD was similar between non-obstructive and obstructive patients ((44% (11/25) vs. 33.3% (24/72), χ 2=0.915, P=0.339). RMBF ((0.83±0.14) ml·min -1·g -1 vs. (0.82±0.17) ml·min -1·g -1), SMBF ((2.13±0.60) ml·min -1·g -1 vs. (1.91±0.50) ml·min -1·g -1) and CFR (2.59±0.66 vs. 2.36±0.47) were similar between the two groups (all P>0.05). Conclusions:CMVD can occur in non-obstructive coronary arteries in both patients with non-occlusive coronary arteries and patients with obstructive coronary arteries. Prevalence of CMVD is significantly higher in patients with obstructive coronary arteries than in patients with non-obstructive coronary arteries. The CMVD severity is similar between the two groups.

Objective To investigate the analgesic efficacy and safety of decozine combined with sufentanil on patients after laparoscopic radical gastrectomy.Methods Sixty patients undergoing laparoscopic radical gastrectomy,American Society of Anesthesiologists (ASA) Ⅰ ～ Ⅱ,were selected,and were randomly divided into two groups.All of the patients were treated with intravenous-inhalation combined anesthesia,and was given patient controlled intraveous analgesia (PCIA) when the patient was awoken.PCIA was administered with subsequent bolus of 0.5 ml with lockout time 15 minutes and background infusion of 2 ml/h.A ratio (3 μg/kg) of sufentanil and 0.5 mg palonosetron were mixed in PCIA pump in sufentanil group (S group);and 1.5 μg/kg sufentanil,0.3 mg/kg dezocine,and 0.5 mg palonosetron in PCIA were mixed in dezocine combined with sufentainl group (DS group),they were diluted to 100 ml with saline.The visual analogue scale (VAS),Bruggrmann comfort scale (BCS),Ramsay and incidence of adverse reactions of two groups were observed in 2 h (T1),6 h (T2),12 h (T3),24 h (T4),48 h(T5) after operation.Results There was no significant difference of VAS and BCS between two groups at each time point after operation (P ＞ 0.05);The Ramsay score of S group was significantly higher than that of DS group at T1,T2,and T3 (P ＜ 0.05).The Ramsay scores of two groups at T4,T5 were lower than those of T1,T2,and T3.The incidence of nausea,vomiting of DS group was significantly lower than that of S group (P ＜0.05).Conclusions Dezocine combined with sufentainl used in PCIA on postoperative gastric cancer patients can obtain satisfactory analgesic effects,but has fewer side effects than single sufentainl.

Objective The aim of this study was to investigate the value of ultrasound in diagnosis of benign and malignant thyroid nodules with rim calcification. Methods Sixty thyroid nodules with rim calcifications from Sun Yat-sen University Cancer center which were detected on ultrasound from January 2008 to December 2015 were included in this study, and all the thyroid nodules had pathological results. Ultrasonic features of thyroid nodules, including the size, border, internal echo, growth pattern, rear echo, interruption or inner sink of the rim calcification and hypoechoic soft tissue extrusion around rim calcification were analyzed. Results Thirty-seven nodules (61.7%) were confirmed to be benign, and twenty-three nodules (38.3%) were malignant. The ultrasonic features of interruption or inner sink of rim calcifications and hypoechoic soft tissue extrusion around rim calcification, were more often in malignant nodules than benign nodules. The sensitivity, specificity, the positive predictive values and the negative predictive values for interruption or inner sink of rim calcifications were 85.7%, 89.4%, 85.7% and 89.4%, respectively. The sensitivity, specificity, the positive predictive values and the negative predictive values for hypoechoic soft tissue extrusion around rim calcification were 81.3%, 94.4%, 92.9% and 85.0%, respectively. Internal hypoechogenicity was more frequently observed in the malignant nodules (82.6%) than in benign nodules (40.5%). The longitudinal growth pattern of thyroid was more frequently observed in malignant nodules (30.4%) than in benign nodules (2.7%). The differences of this two ultrasound features were statistically significant(χ2=9.958 and 9.440,both P<0.01).There were no significant differences in size,border and the rear echo between malignant and benign nodules (all P>0.05). Conclusion The interruption or inner sink of the rim calcification could be useful in differential diagnosis of thyroid nodules with rim calcification.