[Correlation between insulin resistance and coronary collateral circulation in patients with chronic total coronary occlusion]

OBJECTIVE

To explore the impact of diabetes on collateral circulation (CC) development in patients with chronic total coronary occlusion (CTO) and the underlying regulatory mechanism.

METHODS

This study was conducted among 87 patients with coronary heart disease (CHD), who had CTO in at least one vessel as confirmed by coronary angiography. Among them 42 patients were found to have a low CC level (Cohen-Rentrop grades 0-1) and 45 had a high CC level (grades 2-3). In the 39 patients with comorbid diabetes mellitus and 48 non-diabetic patients, insulin resistance (IR) levels were compared between the subgroups with different CC levels. The steady-state mode evaluation method was employed for calculating the homeostatic model assessment for insulin resistance index (HOMA-IR) using a mathematical model. During the interventional procedures, collateral and peripheral blood samples were collected from 22 patients for comparison of the metabolites using non-targeted metabolomics analysis.

RESULTS

NT-proBNP levels and LVEF differed significantly between the patients with different CC levels (P<0.05). In non-diabetic patients, HOMA-IR was higher in low CC level group than in high CC level groups. Compared with the non-diabetic patients, the diabetic patients showed 63 upregulated and 48 downregulated metabolites in the collateral blood and 23 upregulated and 14 downregulated metabolites in the peripheral blood. The differential metabolites in the collateral blood were involved in aromatic compound degradation, fatty acid biosynthesis, and steroid degradation pathways; those in the peripheral blood were related with pentose phosphate metabolism, bacterial chemotaxis, hexanoyl-CoA degradation, glycerophospholipid metabolism, and lysine degradation pathways.

CONCLUSION

The non-diabetic patients with a low level of CC had significant insulin resistance. The degradation pathways of aromatic compounds, fatty acid biosynthesis, and steroid degradation are closely correlated with the development of CC.

Performance and application of the total-body PET/CT scanner: a literature review

BACKGROUND

The total-body positron emission tomography/computed tomography (PET/CT) system, with a long axial field of view, represents the state-of-the-art PET imaging technique. Recently, the total-body PET/CT system has been commercially available. The total-body PET/CT system enables high-resolution whole-body imaging, even under extreme conditions such as ultra-low dose, extremely fast imaging speed, delayed imaging more than 10 h after tracer injection, and total-body dynamic scan. The total-body PET/CT system provides a real-time picture of the tracers of all organs across the body, which not only helps to explain normal human physiological process, but also facilitates the comprehensive assessment of systemic diseases. In addition, the total-body PET/CT system may play critical roles in other medical fields, including cancer imaging, drug development and immunology.

MAIN BODY

Therefore, it is of significance to summarize the existing studies of the total-body PET/CT systems and point out its future direction. This review collected research literatures from the PubMed database since the advent of commercially available total-body PET/CT systems to the present, and was divided into the following sections: Firstly, a brief introduction to the total-body PET/CT system was presented, followed by a summary of the literature on the performance evaluation of the total-body PET/CT. Then, the research and clinical applications of the total-body PET/CT were discussed. Fourthly, deep learning studies based on total-body PET imaging was reviewed. At last, the shortcomings of existing research and future directions for the total-body PET/CT were discussed.

CONCLUSION

Due to its technical advantages, the total-body PET/CT system is bound to play a greater role in clinical practice in the future.

Performance of the Iterative OSEM and HYPER Algorithm for Total-body PET at SUVmax with a Low 18F-FDG Activity, a Short Acquisition Time and Small Lesions

OBJECTIVE

The primary objective of this comparative investigation was to examine the qualitative attributes of image reconstructions utilizing two distinct algorithms, namely OSEM and HYPER Iterative, in total-body 18F- FDG PET/CT under various acquisition durations and injection activities.

METHODS

An initial assessment was executed using a NEMA phantom to compare image quality engendered by OSEM and HYPER Iterative algorithms. Parameters such as BV, COV, and CRC were meticulously evaluated. Subsequently, a prospective cohort study was conducted on 50 patients, employing both reconstruction algorithms. The study was compartmentalized into distinct acquisition time and dosage groups. Lesions were further categorized into three size-based groups. Quantifiable metrics including SD of noise, SUVmax, SNR, and TBR were computed. Additionally, the differences in values, namely ΔSUVmax, ΔTBR, %ΔSUVmax, %ΔSD, and %ΔSNR, between OSEM and HYPER Iterative algorithms were also calculated.

RESULTS

The HYPER Iterative algorithm showed reduced BV and COV compared to OSEM in the phantom study, with constant acquisition time. In the clinical study, lesion SUVmax, TBR, and SNR were significantly elevated in images reconstructed using the HYPER Iterative algorithm in comparison to those generated by OSEM (p < 0.001). Furthermore, an amplified increase in SUVmax was predominantly discernible in lesions with dimensions less than 10 mm. Metrics such as %ΔSNR and %ΔSD in HYPER Iterative exhibited improvements correlating with reduced acquisition times and dosages, wherein a more pronounced degree of enhancement was observable in both ΔSUVmax and ΔTBR.

CONCLUSION

The HYPER Iterative algorithm significantly improves SUVmax and reduces noise level, with particular efficacy in lesions measuring ≤ 10 mm and under conditions of abbreviated acquisition times and lower dosages.

The efficacy of short acquisition time using 18F-FDG total-body PET/CT for the identification of pediatric epileptic foci

BACKGROUND

18F-FDG positron emission tomography (PET) plays a crucial part in the evaluation for pediatric epileptic patients prior to therapy. Short-term scanning holds significant importance, especially for pediatrics epileptic individuals who exhibited involuntary movements. The aim was to evaluate the effects of short acquisition time on image quality and lesion detectability in pediatric epileptic patients using total-body (TB) PET/CT. A total of 25 pediatric patients who underwent TB PET/CT using uEXPLORER scanner with an 18F-FDG administered dose of 3.7 MBq/kg and an acquisition time of 600 s were retrospectively enrolled. Short acquisition times (60 s, 150 and 300 s) were simulated by truncating PET data in list mode to reduce count density. Subjective image quality was scored on a 5-point scale. Regions of interest analysis of suspected epileptogenic zones (EZs), corresponding locations contralateral to EZs, and healthy cerebellar cortex were used to compare the semi-quantitative uptake indices of short-time images and then were compared with 600 s images. The comparison of EZs detectability based on time-dependent PET images was performed.

RESULTS

Our study demonstrated that a short acquisition time of 150 s is sufficient to maintain subjective image quality and lesion significance. Statistical analysis revealed no significant difference in subjective PET image quality between imaging at 300 s and 150 s (P > 0.05). The overall impression scores of image quality and lesion conspicuity in G60s were both greater than 3 (overall quality, 3.21 ± 0.46; lesion conspicuity, 4.08 ± 0.74). As acquisition time decreased, the changes of SUVmax and SD in the cerebellar cortex gradually increased (P < 0.01). There was no significant difference in asymmetry index (AI) difference between the groups and the AIs of EZs were > 15% in all groups. In 26 EZs of 25 patients, the lesion detection rate was still 100% when the time was reduced to 60 s.

CONCLUSIONS

This study proposed that TB PET/CT acquisition time could be reduced to 60 s with acceptable lesion detectability. Furthermore, it was suggested that a 150 s acquisition time would be sufficient to achieve diagnostic performance and image quality for children with epilepsy.

Metabolic interactions between organs in overweight and obesity using total-body positron emission tomography

BACKGROUND AND OBJECTIVES

Overweight and obesity is a complex condition resulting from unbalanced energy homeostasis among various organs. However, systemic abnormalities in overweight and obese people are seldom explored in vivo by metabolic imaging techniques. The aim of this study was to determine metabolic abnormities throughout the body in overweight and obese adults using total-body positron emission tomography (PET) glucose uptake imaging.

METHODS

Thirty normal weight subjects [body mass index (BMI) < 25 kg/m2, 55.47 ± 13.94 years, 16 men and 14 women], and 26 overweight and obese subjects [BMI ≥ 25 kg/m2, 52.38 ± 9.52 years, 21 men and 5 women] received whole-body 18F-fluorodeoxyglucose PET imaging using the uEXPLORER. Whole-body standardized uptake value normalized by lean body mass (SUL) images were calculated. Metabolic networks were constructed based on the whole-body SUL images using covariance network approach. Both group-level and individual-level network differences between normal weight and overweight/obese subjects were evaluated. Correlation analysis was conducted between network properties and BMI for the overweight/obese subjects.

RESULTS

Compared with normal weight subjects, overweight/obese subjects exhibited altered network connectivity strength in four network nodes, namely the pancreas (p = 0.033), spleen (p = 0.021), visceral adipose tissue (VAT) (p = 1.12 × 10-5) and bone (p = 0.021). Network deviations of overweight/obese subjects from the normal weight were positively correlated with BMI (r = 0.718, p = 3.64 × 10-5). In addition, overweight/obese subjects experienced altered connections between organs, and some of the altered connections, including pancreas-right lung and VAT-bilateral lung connections were significantly correlated with BMI.

CONCLUSION

Overweight/obese individuals exhibit metabolic alterations in organ level, and altered metabolic interactions at the systemic level. The proposed approach using total-body PET imaging can reveal individual metabolic variability and metabolic deviations between organs, which would open up a new path for understanding metabolic alterations in overweight and obesity.

Investigation of the quarter-dose 18 F-FDG total-body PET in routine clinical practice and its clinical value

OBJECTIVE

The purpose of the study was to evaluate the routine clinical application of total-body PET with quarter-dose 18 F-FDG.

METHODS

The contrast recovery coefficient (CRC) and coefficient of variation (COV) were evaluated among full-, half-, and quarter-dose groups with an acquisition duration of 10-, 5-, 3-, and 1-min in the NEMA (IQ) phantom test. Fifty patients undergoing total-body PET/CT with quarter-dose (0.925MBq/kg) of 18 F-FDG were included in the prospective study. The acquisition time was 10 min, divided into duration groups of 5-, 3-, and 1-min, referred to as G10, G5, G3, and G1. Visual scores were assessed based on overall visual assessment, noise scoring, and lesion conspicuity. Lesion SUV max and TBR were evaluated in semi-quantitative analysis. G10 was used as the gold reference to evaluate lesion detectability.

RESULTS

In the phantom study, the COV value of the images with quarter-dose 18 F-FDG and 10-min acquisition time was 11.52%. For spheres with 10 mm diameter, the CRC of quarter-dose PET images was relatively stable compared to that of full-dose groups with all acquisition durations. In the human study, the visual score in G10, G5, and G3 was significantly higher than that in G1. The differences in lesion SUV max and TBR for G1-G10 were significantly higher than that for G5-G10 and G3-G10. All lesions in G10 could be identified in G5 and G3.

CONCLUSION

The phantom and human findings demonstrated the feasibility of quarter-dose 18 F-FDG PET with 3-min acquisition time, which can maintain image quality with reduced radiation dose.

The feasibility of quantitative assessment of dynamic 18F-fluorodeoxyglucose PET in Takayasu's arteritis: a pilot study

PURPOSE

PET has been demonstrated to be sensitive for detecting active inflammation in Takayasu's arteritis (TAK) patients, but semi-quantitative-based assessment may be susceptible to various biological and technical factors. Absolute quantification via dynamic PET (dPET) may provide a more reliable and quantitative assessment of TAK-active arteries. The purpose of this study was to investigate the feasibility and efficacy of dPET in quantifying TAK-active arteries compared to static PET.

MATERIALS AND METHODS

This prospective study enrolled 10 TAK-active patients (fulfilled the NIH criteria) and 5 control participants from March to October 2022. One-hour dPET scan (all TAK and control participants) and delayed static PET scan at 2-h (all TAK patients) were acquired. For 1-h static PET, summed images from 50 to 60 min of the dPET were extracted. PET parameters derived from 1- and 2-h static PET including SUV (SUV1H and SUV2H), target-to-background ratio (TBR) (TBR1H and TBR2H), net influx rate (Ki), and TBRKi extracted from dPET were obtained. The detectability of TAK-active arteries was compared among different scanning methods using the generalized estimating equation (GEE) with a logistic regression with repeated measures, and the GEE with gamma distribution and log link function was used to evaluate the different study groups or scanning methods.

RESULTS

Based on the disease states, 5 cases of TAK were classified as untreated and relapsed, respectively. The SUVmax on 2-h PET was higher than that on 1-h PET in the untreated patients (P < 0.05). However, no significant differences were observed in the median SUVmax between 1-h PET and 2-h PET in the relapsed patients (P > 0.05). The TBRKi was significantly higher than both TBR1H and TBR2H (all P < 0.001). Moreover, the detectability of TAK-active arteries by dPET-derived Ki was significantly higher than 1-h and 2-h PET (all P < 0.001). Significant differences were observed in Kimax, SUVmax-1H, TBR1H, and TBRKi among untreated, relapsed, and control groups (all P < 0.05).

CONCLUSIONS

Absolute quantitative assessment by dPET provides an improved sensitivity and detectability in both visualization and quantification of TAK-active arteries. This elucidates the clinical significance of dPET in the early detection of active inflammation and monitoring recurrence.

Rabbit systemic glucose metabolism map by total-body dynamic PET/CT technology

BACKGROUND

This study evaluated total-body glucose metabolism in a preclinical lab animal, the rabbit, by employing a dynamic glucose metabolic image obtained with total-body fluorine-18 fluorodeoxyglucose ( 18 F-FDG) PET/computed tomography (PET/CT).

METHODS

The dynamic total-body PET/CT system was used to obtain glucose metabolic imaging from 10 sedated body-matched rabbits. The standard uptake value (SUV) of 18 F-FDG was used to evaluate glucose metabolism. In addition, the correlation between glucose metabolism and sexes was assessed, as well as metabolic differences between left- and right sides.

RESULTS

We found significant distribution heterogeneity of glucose in several organs across the entire body. There were no significant metabolic differences between sexes and between bilateral sides in the 10 rabbits. Thereafter, we assayed the major organ SUV changes by dynamic PET/CT of the major organs. The heart, liver, and urinary system showed more 18 F-FDG, whereas the skeletal muscle, brain, spinal cord, and lungs incorporated less 18 F-FDG. The phenotype of 18 F-FDG uptake was highly correlated with the physiological functions. The 18 F-FDG accumulation in urinary system were observed which could reflect the renal parenchyma glucose metabolism indirectly. However, the low 18 F-FDG uptake in the brain and spinal cord was due to sedation.

CONCLUSION

The total-body glucose metabolic atlas depicted with 18 F-FDG dynamic PET/CT may be used as a reference for assessing pathological 18 F-FDG uptake. Furthermore, this study could be a reference for preclinical research involving abnormality of glucose metabolism.

Two-dimensional speckle tracking imaging to assess the hazards of left ventricular function and ventricular wall motion disorders in children with pre-excitation syndrome and the efficacy of radiofrequency ablation treatment

OBJECTIVE

Our study aimed at analyzing the echocardiographic multi-indicator evaluation of the risk of Wolff-Parkinson-White syndrome (WPW) on the left ventricular function and ventricular wall motion disorders, as well as the effect of radiofrequency ablation treatment.

PATIENTS AND METHODS

The clinical data of 55 WPW patients treated with radiofrequency (RF) ablation at the Children's Hospital of Nanjing Medical University between January 2018 and December 2022 were retrospectively analyzed and included in the observation group, while other 50 healthy children were included in the control group during the same time. We analyzed the echocardiographic indices of the patients, assessed the effects of the disease on left ventricular myocardial function and ventricular wall motion disorders, and evaluated the effects of radiofrequency ablation treatment on the myocardium of the left ventricle. The echocardiographic parameters were analyzed to assess the effect of the disease on left ventricular myocardial function and ventricular wall dyskinesia.

RESULTS

Of the 55 patients with pre-excited syndrome, 20 had type A bypass and 35 had type B bypass. Ten patients had pre-excited dilated cardiomyopathy with significant enlargement of the left ventricular cavity, reduced left ventricular systolic function, and a significant impairment of ventricular wall motion; the other 5 patients had basal segmental septal motion incoordination. Compared to the control group, patients with left ventricular end-diastolic diameter (LVEDD) (42.9±5.0 mm vs. 39.2±3.0 mm), peak strain dispersion (PSD) (38.8±15.3 ms vs. 21.7±2.2 ms), maximum peak time difference (MPTD) (200.2±92.8 ms vs. 89.5±9.8 ms) and interventricular mechanical delay (IVMD) (36.2±13.7 ms vs. 21.2±2.1 ms) before RF ablation were increased. Left ventricular ejection fraction (LVEF) (57.1±9.1% vs. 65.9±2.6%), E/A (1.1±0.2 vs. 1.8±0.2) and global longitudinal strain (GLS) (-18.7±2.2% vs. -22.4±0.5%) decreased, with statistically significant differences (p<0.05). All 55 patients had a successful procedure, and all postoperative echocardiographic parameters were found to be improved, compared to the preoperative period. The results of the postoperative review after 3 months showed differences in E/A, PSD, MPTD, and IVMD compared to the healthy group, suggesting that left ventricular diastolic function and synchrony had not fully returned to normal.

CONCLUSIONS

Echocardiography can better evaluate myocardial motion and function in patients with Wolff-Parkinson-White syndrome and monitor the effect and progress of disease treatment, and has high clinical application value.

Influence of the concentrate inclusion level in a grass silage-based diet on hepatic transcriptomic profiles in Holstein-Friesian dairy cows in early lactation

Excessive negative energy balance in early lactation is linked to an increased disease risk but may be mitigated by appropriate nutrition. The liver plays central roles in both metabolism and immunity. Hepatic transcriptomic profiles were compared between 3 dietary groups in each of 40 multiparous and 18 primiparous Holstein-Friesian cows offered isonitrogenous grass silage-based diets with different proportions of concentrates: (1) low concentrate (LC, 30% concentrate + 70% grass silage); (2) medium concentrate (MC, 50% concentrate + 50% grass silage), or (3) high concentrate (HC, 70% concentrate + 30% grass silage). Liver biopsies were taken from all cows at around 14 d in milk for RNA sequencing, and blood metabolites were measured. The sequencing data were analyzed separately for primiparous and multiparous cows using CLC Genomics Workbench V21 (Qiagen Digital Insights), focusing on comparisons between HC and LC groups. More differentially expressed genes (DEG) were seen between the primiparous cows receiving HC versus LC diets than for multiparous cows (597 vs. 497), with only 73 in common, indicating differential dietary responses. Multiparous cows receiving the HC diet had significantly higher circulating glucose and insulin-like growth factor-1 and lower urea than those receiving the LC diet. In response to HC, only the multiparous cows produced more milk. In these animals, bioinformatic analysis indicated expression changes in genes regulating fatty acid metabolism and biosynthesis (e.g., ACACA, ELOVL6, FADS2), increased cholesterol biosynthesis (e.g., CYP7A1, FDPS, HMGCR), downregulation in hepatic AA synthesis (e.g., GPT, GCLC, PSPH, SHMT2), and decreased expression of acute phase proteins (e.g., HP, LBP, SAA2). The primiparous cows on the HC diet also downregulated genes controlling AA metabolism and synthesis (e.g., CTH, GCLC, GOT1, ODC1, SHMT2) but showed higher expression of genes indicative of inflammation (e.g., CCDC80, IL1B, S100A8) and fibrosis (e.g., LOX, LUM, PLOD2). This potentially adverse response to a HC diet in physically immature animals warrants further investigation.

Glucose uptake and distribution across the human skeleton using state-of-the-art total-body PET/CT

A growing number of studies have demonstrated that the skeleton is an endocrine organ that is involved in glucose metabolism and plays a significant role in human glucose homeostasis. However, there is still a limited understanding of the in vivo glucose uptake and distribution across the human skeleton. To address this issue, we aimed to elucidate the detailed profile of glucose uptake across the skeleton using a total-body positron emission tomography (PET) scanner. A total of 41 healthy participants were recruited. Two of them received a 1-hour dynamic total-body ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET scan, and all of them received a 10-minute static total-body ¹⁸F-FDG PET scan. The net influx rate (K_i) and standardized uptake value normalized by lean body mass (SUL) were calculated as indicators of glucose uptake from the dynamic and static PET data, respectively. The results showed that the vertebrae, hip bone and skull had relatively high K_i and SUL values compared with metabolic organs such as the liver. Both the K_i and SUL were higher in the epiphyseal, metaphyseal and cortical regions of long bones. Moreover, trends associated with age and overweight with glucose uptake (SUL_max and SUL_mean) in bones were uncovered. Overall, these results indicate that the skeleton is a site with significant glucose uptake, and skeletal glucose uptake can be affected by age and dysregulated metabolism.

Role of breath-hold lung PET in stage IA pulmonary adenocarcinoma

BACKGROUND

Respiratory motion during PET acquisition may result in image blurring and resolution loss, reduced measurement of radiotracer uptake, and consequently, inaccurate lesion quantification and description. With the introduction of the total-body PET system, short-time PET acquisition is feasible due to its high sensitivity and spatial resolution. The purpose of this study was to evaluate the additional value of 20-s breath-hold (BH) lung PET in patients with stage IA pulmonary adenocarcinoma.

METHODS

Forty-seven patients with confirmed stage IA pulmonary adenocarcinoma were enrolled in this retrospective study. All patients underwent a 300-s FB whole-body PET, followed by a BH lung PET. The SUV_max, TBR of the lesions and the percentage difference in nodule SUV_max (%ΔSUV_max) and TBR (%ΔTBR) between the two acquisitions was also calculated. The lesions were further divided by distance from pleura for subgroup analysis. The lesion detectability on PET images was the percentage of FDG-positive lesions.

RESULTS

Among 47 patients, the BH lung PET images identified all lung nodules, and there was a significant difference in overall nodule SUV_max and TBR between BH PET and FB PET (both p < 0.01). The %ΔSUV_max and %ΔTBR were significantly higher in nodules adjacent to pleura (≤ 10 mm in distance) than those away from pleura (both p < 0.05). The lesion detectability of BH lung PET was significantly higher than that of FB PET (p < 0.01).

CONCLUSION

BH PET acquisition is a practical way to minimize motion artifacts in PET which has the potential to improve lesion detection for stage IA pulmonary adenocarcinoma.

CRITICAL RELEVANCE STATEMENT

BH PET acquisition is a practical way to minimize motion artifacts in PET which has the potential to improve lesion detection for stage IA pulmonary adenocarcinoma.

[Aloin inhibits gastric cancer cell proliferation and migration by suppressing the STAT3/HMGB1 signaling pathway]

OBJECTIVE

To investigate the molecular mechanism underlying the inhibitory effect of aloin on the proliferation and migration of gastric cancer cells.

METHODS

Human gastric cancer MGC-803 cells treated with 100, 200 and 300 μg/mL aloin were examined for changes in cell viability, proliferation and migration abilities using CCK-8, EdU and Transwell assays. HMGB1 mRNA level in the cells was detected with RT-qPCR, and the protein expressions of HMGB1, cyclin B1, cyclin E1, E-cadherin, MMP-2, MMP-9 and p-STAT3 were determined using Western blotting. JASPAR database was used to predict the binding of STAT3 to HMGB1 promoter. In a BALB/c-Nu mouse model bearing subcutaneous MGC-803 cell xenograft, the effect of intraperitoneal injection of aloin (50 mg/kg) on tumor growth was observed. The protein expressions of HMGB1, cyclin B1, cyclin E1, E-cadherin, MMP-2, MMP-9 and p-STAT3 in the tumor tissue was examined using Western blotting, and tumor metastasis in the liver and lung tissues was detected using HE staining.

RESULTS

Treatment with aloin concentration-dependently inhibited the viability of MGC-803 cells (P < 0.05), significantly reduced the number of EdU-positive cells (P < 0.01), and attenuated the migration ability of the cells (P < 0.01). Aloin treatment dose-dependently down-regulated HMGB1 mRNA expression (P < 0.01), lowered the protein expressions of HMGB1, cyclin B1, cyclin E1, MMP-2, MMP-9 and p-STAT3, and up-regulated E-cadherin expression in MGC-803 cells. Prediction based on JASPAR database suggested that STAT3 could bind to the promoter region of HMGB1. In the tumor-bearing mice, aloin treatment significantly reduced the tumor size and weight (P < 0.01), lowered the protein expressions of cyclin B1, cyclin E1, MMP-2, MMP-9, HMGB1 and p-STAT3 and increased the expression of E-cadherin in the tumor tissue (P < 0.01).

CONCLUSION

Aloin attenuates the proliferation and migration of gastric cancer cells by inhibiting the STAT3/HMGB1 signaling pathway.

Total-body low-dose CT image denoising using a prior knowledge transfer technique with a contrastive regularization mechanism

PURPOSE

Reducing the radiation exposure experienced by patients in total-body computed tomography (CT) imaging has attracted extensive attention in the medical imaging community. A low radiation dose may result in increased noise and artifacts that greatly affect the subsequent clinical diagnosis. To obtain high-quality total-body low-dose CT (LDCT) images, previous deep learning-based research works developed various network architectures. However, most of these methods only employ normal-dose CT (NDCT) images as ground truths to guide the training process of the constructed denoising network. As a result of this simple restriction, the reconstructed images tend to lose favorable image details and easily generate oversmoothed textures. This study explores how to better utilize the information contained in the feature spaces of NDCT images to guide the LDCT image reconstruction process and achieve high-quality results.

METHODS

We propose a novel intratask knowledge transfer (KT) method that leverages the knowledge distilled from NDCT images as an auxiliary component of the LDCT image reconstruction process. Our proposed architecture is named the teacher-student consistency network (TSC-Net), which consists of teacher and student networks with identical architectures. By employing the designed KT loss, the student network is encouraged to emulate the teacher network in the representation space and gain robust prior content. In addition, to further exploit the information contained in CT scans, a contrastive regularization mechanism (CRM) built upon contrastive learning is introduced. The CRM aims to minimize and maximize the L2 distances from the predicted CT images to the NDCT samples and to the LDCT samples in the latent space, respectively. Moreover, based on attention and the deformable convolution approach, we design a dynamic enhancement module (DEM) to improve the network capability to transform input information flows.

RESULTS

By conducting ablation studies, we prove the effectiveness of the proposed KT loss, CRM, and DEM. Extensive experimental results demonstrate that the TSC-Net outperforms the state-of-the-art methods in both quantitative and qualitative evaluations. Additionally, the excellent results obtained for clinical readings also prove that our proposed method can reconstruct high-quality CT images for clinical applications.

CONCLUSIONS

Based on the experimental results and clinical readings, the TSC-Net has better performance than other approaches. In our future work, we may explore the reconstruction of LDCT images by fusing the positron emission tomography (PET) and CT modalities to further improve the visual quality of the reconstructed CT images.

P04.01.B High impact of ITGB1 on Pi3K/AKT expression in medulloblastoma

Medulloblastoma, an embryonal tumor of the cerebellum, is one of the most frequent malignant brain tumors. Despite the increasing use of genetic variation in treatment stratification, high-risk patients characterized by light meningeal spread, TP53 mutations, or MYC amplification still have poor survival. Phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling is one of the most important intracellular pathways, which can be considered as a master regulator for cancer. In tissue samples obtained from medulloblastoma patients, the significant upregulation of PI3K/AKT was associated with a lifting expression level of integrin β1(ITGB1). To understand the underlying mechanism, we investigated the effect of ITGB1 on the PI3K/AKT pathway in medulloblastoma cell lines. Transfection of this ITGB1 reduced proliferation and invasion of several medulloblastoma cell lines and inhibit epithelial-mesenchymal transition. In addition, knocking down ITGB1 expression can significantly inhibit the activation of PI3K/AKT signaling pathway. In conclusion, ITGB1 may selectively activation the pathophysiological effect of aberrant PI3K/AKT expression and serve as a targeted approach for medulloblastoma therapy.

FDG PET Scan Durations via Effective Data Processing

BACKGROUND

Total-body dynamic PET (dPET) imaging using ¹⁸ F-fluorodeoxyglucose (¹⁸ F-FDG) has received widespread attention in clinical oncology. However, the conventionally required scan duration of approximately 1 hour seriously limits the application and promotion of this imaging technique. In this study, we investigated the possibility and feasibility of shortening the total-body dynamic scan duration to 30 min post-injection (PI) with the help of a novel Patlak data processing algorithm for accurate K_i estimations of tumor lesions.

METHODS

Total-body dPET images acquired by uEXPLORER (United Imaging Healthcare Inc.) using ¹⁸ F-FDG of 15 patients with different tumor types were analyzed in this study. Dynamic images were reconstructed into 25 frames with a specific temporal dividing protocol for the scan data acquired 1 hour PI. Patlak analysis-based K_i parametric imaging was conducted based on the imaging data corresponding to the first 30 min PI, during which a Patlak data processing method based on cubit Hermite interpolation (THI) was applied. The resultant K_i images acquired by 30-min dynamic PET data and the standard 1-hour K_i images were compared in terms of visual imaging effect, region signal-to-noise ratio (SNR), and K_i estimation accuracy to evaluate the performance of the proposed K_i imaging method with a shortened scan duration.

RESULTS

With the help of Patlak data processing, acceptable K_i parametric images were obtained from dynamic PET data acquired with a scan duration of 30 min PI. Compared with K_i images obtained from unprocessed Patlak data, the resulting images from the proposed method performed better in terms of noise reduction. Moreover, Bland-Altman (BA) plot and Person correlation coefficient (PPC) analysis showed that that 30-min K_i images obtained from the processed Patlak data had higher accuracy for tumor lesions.

CONCLUSION

Satisfactory K_i parametric images with high tumor accuracy can be acquired from dynamic imaging data corresponding to the first 30 min PI. Patlak data processing can help achieve higher K_i imaging quality and higher accuracy regarding tumor lesion K_i values. Clinically, it is possible to shorten the dynamic scan duration of ¹⁸ F-FDG PET to 30 min to acquire an accurate tumor K_i and further effective tumor detection with uEXPLORER scanners. This article is protected by copyright. All rights reserved.

Expert consensus on oncological [18F]FDG total-body PET/CT imaging (version 1)

BACKGROUND

[¹⁸F]FDG imaging on total-body PET/CT (TB PET/CT) scanners, with improved sensitivity, offers new potentials for cancer diagnosis, staging, and radiation treatment planning. This consensus provides the protocols for clinical practices with a goal of paving the way for future studies with the total-body scanners in oncological [¹⁸F]FDG TB PET/CT imaging.

METHODS

The consensus was summarized based on the published guidelines and peer-reviewed articles of TB PET/CT in the literature, along with the opinions of the experts from major research institutions with a total of 40,000 cases performed on the TB PET/CT scanners.

RESULTS

This consensus describes the protocols for routine and dynamic [¹⁸F]FDG TB PET/CT scanning focusing on the reduction of imaging acquisition time and FDG injected activity, which may serve as a reference for research and clinic oncological PET/CT studies.

CONCLUSION

This expert consensus focuses on the reduction of acquisition time and FDG injected activity with a TB PET/CT scanner, which may improve the patient throughput or reduce the radiation exposure in daily clinical oncologic imaging.

KEY POINTS

• [¹⁸F]FDG-imaging protocols for oncological total-body PET/CT with reduced acquisition time or with different FDG activity levels have been summarized from multicenter studies. • Total-body PET/CT provides better image quality and improved diagnostic insights. • Clinical workflow and patient management have been improved.

AB0096 MECHANISM OF SHIP IN NEUTROPHIL EXTRACELLULAR TRAP IN RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis（RA） is a common autoimmune disease with unknown etiology. RA is characterized by the destruction of cartilage and bone. Neutrophils are abundant in synovial fluid of RA and are closely related to the development of RA 1。In recent years, it has been reported that neutrophils can release neutrophil extracellular traps（NET）, which can not only kill different bacteria and viruses, but also closely related to autoimmune diseases 1,2 Studies have shown that NET is involved in the development of RA3. The Src homologous 2 domain containing inositol 5-phosphatase 1 (SHIP-1) controls the level of intracellular inositol 3-phosphate kinase product phosphatidylinositol-3,4,5-triphosphate. SHIP can be used as a positive or negative regulatory signal in different stimuli.And So has studied that the inflammation of CIA mouse model is reduced after SHIP is inhibited.

Objectives

Therefore, we want to study whether SHIP is involved in the formation of rheumatoid arthritis NET and its relationship with NET.

Methods

We isolated neutrophils from RA peripheral blood, stimulated NETosis with PMA, and detected the changes of NETosis in the group with SHIP inhibitor by flow cytometry and immunofluorescence. In addition, DBA mice were divided into three groups: HC, CIA and SHIP inhibitor intraperitoneal injection group. The degree of paw swelling and HE staining were used to detect the inflammation of mice, and the release of NET in CIA model was detected by flow cytometry.

Results

In the DBA model, the generation of neutrophil extracellular traps decreased significantly in the intraperitoneal injection group of SHIP inhibitor. SHIP inhibitor can significantly inhibit the formation of NET in RA patients. In addition, we also found TNF- α Monoclonal antibodies reduced NETosis in RA patients, while SHIP inhibitors inhibited the generation of NET in RA patients. The results suggest that SHIP may inhibit the inflammatory factor TNF- α. In turn, it is involved in the release of NET in rheumatoid arthritis

Conclusion

SHIP participates in the formation of NET in rheumatoid arthritis and affects the production of NET through pro-inflammatory cytokines. Therefore, SHIP is expected to become a new target for the treatment of RA.

References

[1]Skopelja-Gardner, S.; Jones, J. D.; Rigby, W. F. C. “NETtling” the Host: Breaking of Tolerance in Chronic Inflammation and Chronic Infection. J. Autoimmun.2018, 88, 1–10. https://doi.org/10.1016/j.jaut.2017.10.008.

[2]Lee, K. H.; Kronbichler, A.; Park, D. D.-Y.; Park, Y.; Moon, H.; Kim, H.; Choi, J. H.; Choi, Y.; Shim, S.; Lyu, I. S.; Yun, B. H.; Han, Y.; Lee, D.; Lee, S. Y.; Yoo, B. H.; Lee, K. H.; Kim, T. L.; Kim, H.; Shim, J. S.; Nam, W.; So, H.; Choi, S.; Lee, S.; Shin, J. I. Neutrophil Extracellular Traps (NETs) in Autoimmune Diseases: A Comprehensive Review. Autoimmun. Rev.2017, 16 (11), 1160–1173. https://doi.org/10.1016/j.autrev.2017.09.012.

[3]Khandpur, R.; Carmona-Rivera, C.; Vivekanandan-Giri, A.; Gizinski, A.; Yalavarthi, S.; Knight, J. S.; Friday, S.; Li, S.; Patel, R. M.; Subramanian, V.; Thompson, P.; Chen, P.; Fox, D. A.; Pennathur, S.; Kaplan, M. J. NETs Are a Source of Citrullinated Autoantigens and Stimulate Inflammatory Responses in Rheumatoid Arthritis. Sci. Transl. Med.2013, 5 (178), 178ra40-178ra40. https://doi.org/10.1126/scitranslmed.3005580.

Disclosure of Interests

None declared

Recognizing Tumor Origin for Lymphoid Tumor of Unknown Primary via Total-Body PET/CT Scan—Case Report

Localizing the site of tumor origin for patients with lymphoid tumor is fairly difficult before the definitive detection of the primary tumor, which causes redundant imaging examinations and medical costs. To circumvent this obstacle, the emergence of the world’s first total-body positron emission tomography/computed tomography (PET/CT) provides a transformative platform for simultaneously static and dynamic human molecular imaging. Here, we reported a case of lymph node metastasis from an unknown primary tumor, and the primary tumor was detected with the aid of the total-body PET/CT scanner. This patient with right neck mass was subjected to static and dynamic PET scan, as the static PET imaging found irregular thickening of the upper rectal wall and the dynamic PET imaging recognized the associations between the lymph metastasis and the rectal tumor lesions. The diagnosis by the total-body PET/CT was confirmed by pathological examination.

Dynamic PET Imaging Using Dual Texture Features

Purpose: This study aims to explore the impact of adding texture features in dynamic positron emission tomography (PET) reconstruction of imaging results. Methods: We have improved a reconstruction method that combines radiological dual texture features. In this method, multiple short time frames are added to obtain composite frames, and the image reconstructed by composite frames is used as the prior image. We extract texture features from prior images by using the gray level-gradient cooccurrence matrix (GGCM) and gray-level run length matrix (GLRLM). The prior information contains the intensity of the prior image, the inverse difference moment of the GGCM and the long-run low gray-level emphasis of the GLRLM. Results: The computer simulation results show that, compared with the traditional maximum likelihood, the proposed method obtains a higher signal-to-noise ratio (SNR) in the image obtained by dynamic PET reconstruction. Compared with similar methods, the proposed algorithm has a better normalized mean squared error (NMSE) and contrast recovery coefficient (CRC) at the tumor in the reconstructed image. Simulation studies on clinical patient images show that this method is also more accurate for reconstructing high-uptake lesions. Conclusion: By adding texture features to dynamic PET reconstruction, the reconstructed images are more accurate at the tumor.

Quality detection of tea oil by 19F NMR and 1H NMR

The nuclear magnetic resonance (NMR) technique was applied to monitor the quality of tea oil herein. The adulteration of virgin tea oil was monitored by 19F NMR and 1H NMR. The 19F NMR technique was used as a new method to detect the changes in quality and hydroperoxide value of tea oil. The research demonstrates that 19F NMR and 1H NMR can quickly detect adulteration in tea oil. High temperature caused a decrease in the ratio D and increase in the total diglyceride content. Some new peaks belonging to the derivatives of hydroperoxides appeared at δ-108.21 and δ-109.05 ppm on the 19F NMR spectrum when the oil was autoxidized and became larger when the hydroperoxide value increased. These results have great significance in monitoring the moisture content, freshness and oxidation status of oils and in detecting adulteration in high priced edible oils by mixing with cheap oils.

Bifocal 532/1064 nm alternately illuminated photoacoustic microscopy for capturing deep vascular morphology in human skin

BACKGROUND

As a promising technology, photoacoustic microscopy (PAM) plays a critical role in diagnosis and assessment of dermatological conditions by providing subtle vascular networks non-invasively. However, the established PAMs are insufficient for clinical dermatology when faced with complex structures of human skin instead of animal models owing to high melanin content and superimposed vasculature for Asians, which cannot balance the spatial resolution and the imaging depth.

OBJECTIVES

To evaluate the ability of bifocal 532/1064-nm alternately illuminated photoacoustic microscopy (BF-PAM) to non-invasively reveal the morphological structure of human skin for improving the diagnosis and therapeutic efficacy of skin diseases.

METHODS

A BF-PAM was developed to capture biopsy-like information of human skin from epidermis to hypodermis. The optical foci of the two excitation beams are staggered in the axial direction to form an extended depth-of-field, which can maintain the lateral resolution and the contrast of PA image.

RESULTS

The imaging capability of the BF-PAM was demonstrated by depicting the vascular morphology of multilayered skin with imaging depth of ˜3 mm. Furtherly, vascular malformations in port-wine stains skin were quantitatively assessed without the need for any contrast agent, and the distribution, depth and diameter of the ectatic vessels can determine an optimal treatment protocol for port-wine stains lesions.

CONCLUSIONS

The quantitative vascular morphology in the dermis can be used to accurately assess vascular characteristics, in which case it enables clinicians to determine optimum treatment parameters in individual patients. As a non-invasive imaging technique, BF-PAM holds great potential to provide objective assessment to enhance the therapeutic efficacy.

ETHICAL STATEMENT

The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by the Chinese Ethics Committee of Registering Clinical Trials (ChiECRCT20200184) and registered with Chinese Clinical Trial Registry (ChiCTR2000034400). Before skin imaging, written informed consent was taken from all individual participants.

Effect of low temperature and high humidity stress on physiology of cucumber at different leaf stages

Low temperature (LT) and high humidity (HH) are important environmental factors in greenhouses and plastic tunnels during the cold season, as they hamper plant growth and development. Here, we studied the effect of LT (day/night: 9/5 °C, 25/18 °C as control) and HH (95%, 80% as control) on young cucumber plants at the 2, 4 or 6 leaf stages. LT+HH stress resulted in a decline in shoot, root and total fresh and dry weights, and decreased P_n , g_s , T_r , F_v /F_m , qP, ETR and chlorophyll, and increased MDA, H₂ O₂ , O₂ ^- , NPQ and C_i as compared to the control at the 2 leaf stage. SOD, POD, CAT, APX and GR were upregulated under LT+HH stress as compared to the control at the 6 leaf stage. ABA and JA increased under LT+HH stress as compared to the control at the 6 leaf stage, while IAA and GA decreased under LT+HH stress as compared to the control at the 2 leaf stage. Our results show that LT+HH stress affects young cucumber plant photosynthetic efficiency, PSII activity, antioxidant defence system, ROS and hormone profile. Plants at the 6 leaf stage were more tolerant than at the 2 and 4 leaf stages under stress conditions.

Effect of diet and nonesterified fatty acid levels on global transcriptomic profiles in circulating peripheral blood mononuclear cells in early lactation dairy cows

After calving, lipid mobilization caused by increased nutrient demands for lactation leads to elevated circulating concentrations of nonesterified fatty acids (NEFA). Excessive NEFA levels have previously been identified as a major risk factor for postpartum immunosuppression. The aim of this study was to investigate changes in global transcriptomic gene expression of peripheral blood mononuclear cells (PBMC) in dairy cows offered different early lactation diets (high concentrate, n = 7; medium, n = 8; or low, n = 9) and with differing circulating levels of NEFA. Cows were classified as having NEFA concentrations of either <500 µM (low, n = 6), 500 to 750 µM (medium, n = 8) or >750 µM (high, n = 10) at 14 d in milk. Plasma urea concentrations were greater for cows on the high concentrate diet but β-hydroxybutyrate and glucose concentrations did not differ significantly between either dietary treatments or NEFA groups. Cows with high NEFA weighed more at drying off and suffered greater body condition score loss after calving. The PBMC were isolated at 14 d in milk, and RNA was extracted for RNA sequencing. Differential gene expression was analyzed with DESeq2 with q-value for false discovery rate control followed by Gene Ontology Enrichment. Although there were no differentially expressed genes associated with lactation diet, 304 differentially expressed genes were identified between cows with high and low circulating NEFA, with 118 upregulated and 186 downregulated. Gene Ontology enrichment analysis demonstrated that biological adhesion and immune system process were foremost among various PBMC functions which were altered relating to body defenses and immunity. High NEFA concentrations were associated with inhibited cellular adhesion function by downregulating 20 out of 26 genes (by up to 17-fold) related to this process. Medium NEFA concentrations altered a similar set of functions as high NEFA, but with smaller enrichment scores. Localization and immune system process were most significant, with biological adhesion ranking only eleventh. Our results demonstrated that increased circulating NEFA concentrations, but not diet, were associated with immune system processes in PBMC in early lactation cows. Leukocyte cell-to-cell adhesion was inhibited when the NEFA concentration exceeded 750 µM, which would reduce the efficiency of diapedesis and so contribute to decreased body defense mechanisms and predispose animals to infection.

Identification of hepatosensitive region and their neural connections in the hippocampus of rats

BACKGROUND

Visceral function localization of the brain is very complex. For many years, people have been actively exploring the neural mechanism regulating visceral and substance metabolism, clarifying the complex relationship between the brain and peripheral nervous system related to the regulation of visceral activity, and analyzing its complex neural pathways. The brain is the advanced center of visceral function regulation. As an advanced center for substance metabolism and visceral regulation, the hippocampus is crucial for regulating visceral function. The liver is the core organ of material metabolism, and its afferent signals are mainly projected to the Nucleus of the solitary tract(NTS) through vagus nerve, and then they are projected to the hypothalamus and limbic system.

MATERIALS AND METHODS

We placed a stereotaxic instrument on the head of each rat and performed craniotomy to open a window above the left hippocampus. We used gold-plated tungsten electrodes to monitor hippocampal neuronal discharges. Grounding was achieved using screws and silver wire. We electrically stimulated the liver branch of the vagus nerve and observed changes in hippocampal neuron discharges using a biological method; in this way, we identified hepatosensitive hippocampal region. We injected FluoroGold into this region and related brain areas. After 3 days, the rats were sacrificed and perfused; the hippocampi were fixed, dehydated, frozen, sectioned, and subjected to fluorescence microscopy.

RESULTS

Nerve discharge frequency and amplitude significantly increased in the hippocampal CA3 region (AP: -4.9, ML: -5.1, DV: -5.0 mm). After FluoroGold was injected into the left hepatosensitive region in the hippocampus, labeled cells were found in the contralateral hippocampus, ipsilateral piriform cortex (PC), locus coeruleus (LC) and bilateral lateral hypothalamus (LHA); fluorescence in the ipsilateral hypothalamus was stronger than that of the contralateral hypothalamus. FluoroGold was injected into the LHA, PC, and LC; no labeled cells were found in the hippocampal CA3 region or in the control group.

CONCLUSIONS

The hippocampal CA3 area of rats may contain a hepatosensitive region that plays important roles in the regulation of liver and other organ function. These region may receive input from the LHA, PC, and LC.

Relationships between metabolic profiles and gene expression in liver and leukocytes of dairy cows in early lactation

Homeorhetic mechanisms assist dairy cows in the transition from pregnancy to lactation. Less successful cows develop severe negative energy balance (NEB), placing them at risk of metabolic and infectious diseases and reduced fertility. We have previously placed multiparous Holstein Friesian cows from 4 herds into metabolic clusters, using as biomarkers measurements of plasma nonesterified fatty acids, β-hydroxybutyrate, glucose and IGF-1 collected at 14 and 35 d in milk (DIM). This study characterized the global transcriptomic profiles of liver and circulating leukocytes from the same animals to determine underlying mechanisms associated with their metabolic and immune function. Liver biopsy and whole-blood samples were collected around 14 DIM for RNA sequencing. All cows with available RNA sequencing data were placed into balanced (BAL, n = 44), intermediate (n = 44), or imbalanced (IMBAL, n = 19) metabolic cluster groups. Differential gene expression was compared between the 3 groups using ANOVA, but only the comparison between BAL and IMBAL cows is reported. Pathway analysis was undertaken using DAVID Bioinformatic Resources (https://david.ncifcrf.gov/). Milk yields did not differ between BAL and IMBAL cows but dry matter intake was less in IMBAL cows and they were in greater energy deficit at 14 DIM (-4.48 v -11.70 MJ/d for BAL and IMBAL cows). Significantly differentially expressed pathways in hepatic tissue included AMPK signaling, glucagon signaling, adipocytokine signaling, and insulin resistance. Genes involved in lipid metabolism and cholesterol transport were more highly expressed in IMBAL cows but IGF1 and IGFALS were downregulated. Leukocytes from BAL cows had greater expression of histones and genes involved in nucleosomes and cell division. Leukocyte expression of heat shock proteins increased in IMBAL cows, suggesting an unfolded protein response, and several key genes involved in immune responses to pathogens were upregulated (e.g., DEFB13, HP, OAS1Z, PTX3, and TLR4). Differentially expressed genes upregulated in IMBAL cows in both tissues included CD36, CPT1, KFL11, and PDK4, all central regulators of energy metabolism. The IMBAL cows therefore had greater difficulty maintaining glucose homeostasis and had dysregulated hepatic lipid metabolism. Their energy deficit was associated with a reduced capacity for cell division and greater evidence of stress responses in the leukocyte population, likely contributing to an increased risk of infectious disease.

Spinal schwannoma causes acute subarachnoid haemorrhage: A case report and literature review

BACKGROUND

Spinal schwannomas that arise from spinal nerve root sheaths are the most common intradural extramedullary spinal tumours and are often accompanied by nerve roots or spinal cord irritation symptoms. The phenomenon of spinal schwannoma causing subarachnoid haemorrhage (SAH) is rare, with ependymoma of the conus medullaris accounting for most cases.

CASE REPORT

A 45-year-old man was admitted to our hospital due to progressive lower limb weakness and sudden back pain after hard physical work. The patient had not been able to walk for 2hours upon admission. An emergency magnetic resonance imaging (MRI) scan showed that the spinal cord at the C6-T4 level was severely compressed by a subdural mass. During the emergency operation, exploration of the dura and arachnoid mater revealed a fresh blood clot covering a tumour located on the ventral side of the spinal cord. The size of the tumour was approximately 3×2×1cm without adhesion to the surrounding tissue, but the drainage vein was ruptured. Postoperative pathology showed that the tumour was a schwannoma with areas of fresh haemorrhage and focal necrosis.

CONCLUSIONS

Spinal schwannomas presenting with SAH are rare events. In our opinion, spinal pathology with rapid progression of neurological symptoms requires early diagnosis and emergency management. Complete excision of haemorrhagic tumours is the goal of treatment to prevent recurrence, which can effectively avoid irreversible damage to the spinal cord resulting from spinal cord compression.

Impact of co-morbidity on reoperation or death within 90 days of surgery for oesophageal cancer

Background

The impact of preoperative co-morbidity on postoperative outcomes in patients with oesophageal cancer is uncertain. A population-based and nationwide cohort study was conducted to assess the influence of preoperative co-morbidity on the risk of reoperation or mortality within 90 days of surgery for oesophageal cancer.

Methods

This study enrolled 98 per cent of patients who had oesophageal cancer surgery between 1987 and 2015 in Sweden. Modified Poisson regression models provided risk ratios (RRs) with 95 per cent confidence intervals (c.i.) to estimate associations between co-morbidity and risk of reoperation or death within 90 days of oesophagectomy. The RRs were adjusted for age, sex, educational level, pathological tumour stage, neoadjuvant therapy, annual hospital volume, tumour histology and calendar period of surgery.

Results

Among 2576 patients, 446 (17.3 per cent) underwent reoperation or died within 90 days of oesophagectomy. Patients with a Charlson Co-morbidity Index (CCI) score of 2 or more had an increased risk of reoperation or death compared with those with a CCI score of 0 (RR 1.78, 95 per cent c.i. 1.44 to 2.20), and the risk increased on average by 27 per cent for each point increase of the CCI (RR 1.27, 1.18 to 1.37). The RR was increased in patients with pulmonary disease (RR 1.66, 1.36 to 2.04), cardiac disease (RR 1.37, 1.08 to 1.73), diabetes (RR 1.50, 1.14 to 1.99) and cerebral disease (RR 1.40, 1.06 to 1.85).

Conclusion

Co-morbidity in general, and pulmonary disease, cardiac disease, diabetes and cerebral disease in particular, increased the risk of reoperation or death within 90 days of oesophageal cancer surgery. This highlights the value of tailored patient selection, preoperative preparation and postoperative care.

Super-factors associated with transmission of occupational COVID-19 infection among healthcare staff in Wuhan, China

BACKGROUND

Globally, there have been many cases of coronavirus disease 2019 (COVID-19) among medical staff; however, the main factors associated with the infection are not well understood.

AIM

To identify the super-factors causing COVID-19 infection in medical staff in China.

METHODS

A cross-sectional study was conducted between January 1st and February 30th, 2020, in which front-line members of medical staff who took part in the care and treatment of patients with COVID-19 were enrolled. Epidemiological and demographic data between infected and uninfected groups were collected and compared. Social network analysis (SNA) was used to establish socio-metric social links between influencing factors.

FINDINGS

A total of 92 medical staff were enrolled. In all participant groups, the super-factor identified by the network was wearing a medical protective mask or surgical mask correctly (degree: 572; closeness: 25; betweenness centrality: 3.23). Touching the cheek, nose, and mouth while working was the super-factor in the infected group. This was the biggest node in the network and had the strongest influence (degree: 370; closeness: 29; betweenness centrality: 0.37). Self-protection score was the super-factor in the uninfected group but was the isolated factor in the infected group (degree: 201; closeness: 28; betweenness centrality: 5.64). For family members, the exposure history to Huanan Seafood Wholesale Market and the contact history to wild animals were two isolated nodes.

CONCLUSION

High self-protection score was the main factor that prevented medical staff from contracting COVID-19 infection. The main factor contributing to COVID-19 infections among medical staff was touching the cheek, nose, and mouth while working.

Relationships between air particulate matter capture efficiency and leaf traits in twelve tree species from an Italian urban-industrial environment

Air pollution in the urban environment is widely recognized as one of the most harmful threats for human health. International organizations such as the United Nations and the European Commission are highlighting the potential role of nature in mitigating air pollution and are now funding the implementation of Nature-Based Solutions, especially at the city level. Over the past few decades, the attention of the scientific community has grown around the role of urban forest in air pollution mitigation. Nevertheless, the understanding on Particulate Matter (PM) retention mechanisms by tree leaves is still limited. In this study, twelve tree species were sampled within an urban park of an industrial city. Two techniques were used for leaf analysis: Vacuum/Filtration and Scanning Electron Microscopy coupled with Energy Dispersive X-ray spectroscopy, in order to obtain a quali-quantitative analysis of the different PM size fractions. Results showed that deposited PM loads vary significantly among species. Different leaf traits, including micro and macromorphological characteristics, were observed, measured and ranked, with the final aim to relate them with PM load. Even if no significant correlation between each single leaf characteristic and PM deposition was observed (p > 0.05), multivariate analysis revealed relationships between clusters of leaf traits and deposited PM. Thus, by assigning a score to each trait, an Accumulation index (Ai) was calculated, which was significantly related to the leaf deposited PM load (p ≤ 0.05).

[Characteristics and clinical significance of pulmonary function test and KL-6 in ASSD-ILD and IPF]

Objective: To study the characteristics and clinical significance of pulmonary function test and kerbs von den lungen 6 (KL-6) in anti-synthetase syndrome related interstitial lung disease (ASSD-ILD) and idiopathic pulmonary fibrosis (IPF). Methods: The clinical data of 43 patients with ASSD-ILD (ASSD-ILD group) from May 2015 to May 2017 were collected retrospectively, including 12 males and 31 females, and 34 patients with IPF (IPF group) treated in the First Affiliated Hospital of Zhengzhou University during the same period, including 28 males and 6 females, were also included. The basic information, and the value of pulmonary function test [pulmonary function parameters included the forced vital capacity expressed as percent predicted (FVC%pred), the forced expiratory volume in 1 second expressed as percent predicted (FEV(1)%pred), the ratio of FVC to FEV(1) (FVC/FEV(1)), the peak expiratory flow expressed as percent predicted (PEF%pred), the forced expiratory flow at 25%, 50%, 75% of FVC as percent predicted (FEF(25)%pred, FEF(50)%pred, and FEF(75)%pred), the maximum mid-expiratory flow as percent predicted (MMEF% pred), and the diffusing capacity for carbon monoxide as percent predicted (DLCO% pred)], and serum KL-6 level in ASSD-ILD and IPF were compared. Results: The FEV(1)%pred, FEF(50)%pred, FEF(75)%pred, and MMEF%pred values in ASSD-ILD group were significantly lower than those in IPF group (all P<0.05), while the FVC% pred, FVC/FEV(1), PEF% pred, FEF(25)%pred, and DLCO% pred values in ASSD-ILD group had no significant difference compared with IPF group (all P>0.05). There was no significant difference in serum KL-6 level between ASSD-ILD group and IPF group [(1 169±911) vs (1 210±908) U/ml, t=0.62, P=0.463]. Follow-up analysis showed that the serum KL-6 level of ASSD-ILD patients who died within two years was significantly higher than that of survivors [(2 060±1 168) vs (1 042±858) U/ml, t=2.93, P=0.041]. The serum KL-6 level of patients who died within two years of IPF patients was also significantly higher than that of patients who survived [(1 767±865) vs (1 089±894) U/ml, t=2.53, P=0.026]. The serum KL-6 level in ASSD-ILD group was negatively correlated with FVC%pred (r=-0.43, P=0.004), FEV(1)%pred (r=-0.39, P=0.010) and DLCO% pred (r=-0.41, P=0.006). There was no correlation between serum KL-6 level and pulmonary function test indexes in IPF group (all P>0.05). Conclusions: There is difference in pulmonary function test between ASSD-ILD patients and IPF patients. High serum KL-6 level will be predictive of poor prognosis.

[Application value of different lymph node staging system in predicting prognosis of patients with intrahepatic cholangiocarcinoma]

Objective: To examine the value of number of metastatic lymph nodes(NMLN), lymph node ratio(LNR) and log odds of metastatic lymph nodes(LODDS) in assessing the prognosis of patients with intrahepatic cholangiocarcinoma(ICC). Methods: The clinical and pathological data of 440 ICC patients who underwent curative-intent resection in 10 of Chinese hepatobiliary surgery centers from January 2010 to December 2018 were collected, and the deadline of follow-up was April 30th, 2019. Among them, 205 were males and 235 were females, with age of (57.0±9.9) years (range:23-83 years).Eighty-five cases (19.3%) had intrahepatic bile duct stones, and 98 cases (22.3%) had chronic viral hepatitis.The Kaplan-Meier method was used for survival analysis. The univariate and multivariate analysis were implemented respectively using the Log-rank test and Cox proportional hazard model. Results: A total of 440 patients underwent curative-intent resection and lymphadenectomy.R0 resection were achieved in 424 cases (96.4%) and R1 resection were in 16 cases (3.6%). The results of postoperative pathological examination showed that high, moderate and poor differentiation was 4.2%(18/426), 60.6%(258/426) and 35.2%(150/426), respectively.Adenocarcinoma was seen in 90.2%(397/440) and non-adenocarcinoma was seen in 9.8%(43/440), respectively. T stage: 2 cases (0.5%) with Tis, 83 cases(18.9%) with T1a, 97 cases(22.0%) with T1b, 95 cases(21.6%) with T2, 122 cases (27.7%) with T3 and 41 cases(9.3%) with T4.The overall median survival time was 24.0 months, and the 1-,3-, and 5-year survival rate was 74.3%, 37.7% and 18.3%, respectively. Lymphatic metastasis occurred in 175 patients(39.8%), the median total number of TNLE(M(Q(R))) was 6(5), the median number of NMLN was 0(1), the median number of LNR was 0 (0.33) and the median number of LODDS was -0.70(-0.92). Rerults of univariate analysis showed that combined stones, pathological differentiation, vascular invasion, LODDS, margin and T staging affected the prognosis (all P<0.05). Rerults of multivariate analysis showed that pathological differentiation, LODDS, margin, and T staging were independent risk factors affecting the prognosis of ICC patients (all P<0.05). Conclusion: LODDS could be used as an optimal prognostic lymph node staging index for ICC, and it is also an independent risk factor for survival after curative intent resection.

Dynamic Indicators That Impact the Outcomes of Thoracic Endovascular Aortic Repair in Complicated Type B Aortic Dissection

PURPOSE

To investigate dynamic variables obtained from retrospective computed tomography angiography for ability to predict thoracic endovascular aortic repair (TEVAR) outcomes in patients with complicated type B aortic dissection (cTBAD).

MATERIALS AND METHODS

Seventy-nine patients with cTBAD who received TEVAR from March 2009 to June 2018 were retrospectively enrolled. Relative true lumen area (r-TLA) was computed at the level of tracheal bifurcation every 5% of all R-R intervals. Parameters that reflect the state of intimal motion were evaluated, including difference between maximum and minimum r-TLA (D-TLA) and true lumen collapse. The endpoints comprised early (≤ 30 days) and late (> 30 days) outcomes after intervention.

RESULTS

Overall early mortality rate was 13.9% (11/79), and early adverse events rate was 24.1% (19/79). Patients who received TEVAR within 2 days of symptom onset demonstrated the worst outcomes. A longer time of r-TLA < 25% in 1 cardiac cycle (P = .049) and larger D-TLA (P < .001) were correlated to an increased early death. In addition, D-TLA was an independent predictor of early mortality. Area under the curve of D-TLA was 0.849 (95% confidence interval 0.730-0.967) for predicting early mortality and 0.742 (95% CI 0.611-0.873) for predicting early adverse events. Survival and event-free survival rates during follow-up were decreased in the D-TLA > 21.5% group compared with the D-TLA ≤ 21.5% group (all P < .001).

CONCLUSIONS

Larger D-TLA is correlated with worse postoperative outcomes and might be a crucial parameter for future risk stratification in patients with cTBAD.

Dynamic Imaging Features of Retrospective Cardiac Gating CT Angiography Influence Delayed Adverse Events in Acute Uncomplicated Type B Aortic Dissections

PURPOSE

To investigate the correlation between dynamic morphological parameters of retrospective cardiac gating CT angiography (CTA) and delayed adverse event (DAE) in uncomplicated type B acute aortic dissection (uTB-AAD) patients.

MATERIALS AND METHODS

Eighty-seven patients initially diagnosed with uTB-AAD were retrospectively reviewed. Dynamic variables obtained by dose-regulated retrospective CTA were recorded, including the minimum relative true lumen diameter (RTLA_min), ratio of the minimum to maximum true lumen relative area (r-RTLA), the maximum diameter of the descending aorta, false lumen, and primary entry tear. Outcome analysis comprised incidences of DAE and early mortality within 3 to 14 days since symptom occurring.

RESULTS

Twenty-six patients (29.9%) developed DAE, and two of which (7.7%) died before any interventions. Smaller values of RTLA_min (P = 0.01) and r-RTLA at the upper thoracic descending aorta (UTDA) (P < 0.001), and r-RTLA at the renal artery level (P = 0.016) demonstrated higher incidences of DAE; maximum diameter of the descending aorta (P < 0.001), the false lumen (P = 0.008), and entry tear size (P = 0.007) were positively associated with the occurrence of DAE. r-RTLA at the UTDA level yielded the highest diagnostic accuracy (82.0%) in detecting DAE at an optimal cutoff value of 61.7% (AUC = 0.839). Performance of dynamic characteristics was superior to static features obtained from single-phase image in the detection of DAE (P < 0.001).

CONCLUSION

Dynamic morphological features of retrospective cardiac gating CTA might aid in identifying a high risk of DAE in uTB-AAD patients and guiding early targeted interventions.

Effects of miR-155 on hypertensive rats via regulating vascular mesangial hyperplasia

OBJECTIVE

Vascular smooth muscle cell (VSMC) excessive proliferation is related to hypertension. The cell cycle inhibitory factor (p27) can arrest cell cycle, while its down-regulation is associated with hypertension. It is found that microRNA-155 (miR-155) plays a regulatory role in VSMC proliferation, while its relationship with hypertension is still unclear. Bioinformatics analysis reveals the targeted relationship between miR-155 and the 3'-UTR of p27 mRNA. This study aims to explore the role of miR-155 in regulating p27 expression, VSMC proliferation and apoptosis, and the pathogenesis of hypertension.

MATERIALS AND METHODS

Dual luciferase reporter gene assay confirmed the relationship between miR-155 and p27. MiR-155, p27, α-smooth muscle actin (α-SMA), and Ki-67 expressions in the thoracic aorta media of rat hypertension model were detected. VSMCs were cultured in vitro and divided into five groups, including anti-miR-NC, anti-miR-155, pIRES2-blank, pIRES2-p27, and anti-miR-155 + pIRES2-p27 groups. Cell cycle was evaluated by using flow cytometry. Cell proliferation was detected with EdU staining. Hypertension rats were randomly divided into antagomir-155 and antagomir-control. Caudal artery systolic and diastolic pressures were measured.

RESULTS

MiR-155 targeted suppressed p27 expression. MiR-155 and Ki-67 expressions significantly enhanced, while p27 and α-SMA levels reduced in the tunica media from hypertension rats compared with control. Down-regulation of miR-155 and/or up-regulation of p27significantly declined cell proliferation and arrested cell cycle in G1 phase. Antagomir-155 injection markedly decreased systolic and diastolic pressures, elevated p27 and α-SMA expressions in media, and reduced the thickness of tunica media.

CONCLUSIONS

MiR-155 promoted VSMC proliferation by targeting p27. MiR-155 enhancement was related to hypertension. MiR-155 played a therapeutic effect on hypertension.