[Retroviral-mediated transfer of a hygromycin phosphotransferase-thymidine kinase fusion gene into human bladder carcinoma cell]

OBJECTIVE

To evaluate the therapeutic efficacy of retroviral-mediated hygromycin phosphotransferase-thymidine kinase fusion gene (HyTK)/GCV on human bladder carcinoma cell.

METHODS

A retroviral expression vector pL (HyTK) SN was constructed. By using FuGENE 6-mediated transfection and "ping-pong effect" technique, high-titer of retroviral supernatant was obtained and HyTK gene was transferred into EJ cells. A retroviral vector encoding, enhanced green fluorescent protein, EGFP was used to rapidly detect the transduction efficiency. Antitumor effects were observed after GCV treatment.

RESULTS

In vitro experiments demonstrated the EJ cells transferred by HyTK gene were killed in the GCV treatment. Non-transduced parental cells were not sensitive to GCV, but they were dead by the bystander killing of neighboring cells when mixed with EJ/HyTK cells at various ratios. In addition, this not only affect wild-type EJ cells but also cells from different bladder carcinoma cell lines.

CONCLUSIONS

Retroviral-mediated HyTK/GCV systems were a promising suicide gene therapy for bladder carcinoma. EGFP may act as a convenient and rapid reporter to monitor retroviral-mediated gene transfer and expression in bladder carcinoma cells.

[Metallothionein involvement in the delayed protection after ischemic or anoxic preconditioning in myocardium or cultured cardiomyocytes]

OBJECTIVE

To study whether metallothionein (MT) is an OH scavenger and plays a protective role in cardiac ischemic/reperfusion injury. MT involves in the delayed protection 24 hr after preconditioning (PC).

METHODS

MT contents in myocardium or cultured cardiomyocytes are assayed at the 0 hr, 12 hr, and 24 hr after PC on the model of rabbit heart in situ or that of the cultured cardiomyocytes. The myocardial infarct size, LDH release, cell viability, and the content of cellular MDA were measured with or without the intervention of PD098059, the inhibitor of mitogen-activated protein kinase in the models before PC and different time intervals after PC.

RESULTS

The MT contents were increased significantly at 2 hr (1406.2 +/- 112.2 vs 129.9 +/- 10.4 pmol/mg Pr., P < 0.01, in cardiomyocytes) and 24 hr (1032.7 +/- 199.1 vs 129.9 +/- 10.4 pmol/mg Pr., P < 0.01, in cardiomyocytes; 62.1 +/- 12.6 vs 27.2 +/- 3.7 pmol/mg Pr., P < 0.01, in myocardium) after PC compared with those in normal group. The infarct sizes (13.2 +/- 3.6% vs 32.3 +/- 5.7%, P < 0.05) and the rise of LDH release in plasma (1944 +/- 256 vs 2826 +/- 239 IU/L, P < 0.05) were greatly decreased in preconditioned myocardium after a long time ischemia-reperfusion than those in the unpreconditioned. Compared with the cardiomyocytes unconditioned, the number of viable cell (71.0 +/- 1.6 vs 48.2 +/- 2.2%, P < 0.01) was greatly increased, the cellular MDA contents (33.5 +/- 12.8 vs 103.5 +/- 15.0 nmol/mg Pr., P < 0.01) and the LDH release (850.0 +/- 139.1 vs 1552.0 +/- 102.6 IU/L, P < 0.01) were dramatically decreased in preconditioned ones. All the delayed protection at 24 hr after PC were completely disappeared with the inhibition of MT's production with PD098059 (P > 0.05).

CONCLUSION

The myocardium or cardiomyocytes at 24 hr after PC are offered more capacity to tolerate the I/R damage, and MT involves in the delayed protection.

[Pay attention to the diagnosis and treatment of intestinal infectious diarrhea after colorectal surgery]

Colorectal surgery patients have severe intestinal flora disorders and antibiotic resistant bacteria due to the disease itself and preoperative treatment, as well as the influence of dietary structure and environmental factors. Perioperative anesthesia and operative stress can cause gastrointestinal motility disorders. In addition, the widespread use of prophylactic broad-spectrum antibiotics and antiacids aggravate intestinal flora disorders and induces severe postoperative infectious diarrhea, such as pseudomembranous enteritis and fatal enteritis. The clinical manifectation are severe infectious diarrhea with high fever and abdominal distension after surgery. The disease progresses rapidly. When the diagnosis and treatment are delayed, the patient can quickly develop shock and other serious complications such as anastomotic leakage, even die of multiple organ failure. Therefore, early diagnosis and treatment are crucial.

Accurately Predicting Spatiotemporal Variations of Near-Surface Nitrous Acid (HONO) Based on a Deep Learning Approach

Gaseous nitrous acid (HONO) is identified as a critical precursor of hydroxyl radicals (OH), influencing atmospheric oxidation capacity and the formation of secondary pollutants. However, large uncertainties persist regarding its formation and elimination mechanisms, impeding accurate simulation of HONO levels using chemical models. In this study, a deep neural network (DNN) model was established based on routine air quality data (O3, NO2, CO, and PM2.5) and meteorological parameters (temperature, relative humidity, solar zenith angle, and season) collected from four typical megacity clusters in China. The model exhibited robust performance on both the train sets [slope = 1.0, r2 = 0.94, root mean squared error (RMSE) = 0.29 ppbv] and two independent test sets (slope = 1.0, r2 = 0.79, and RMSE = 0.39 ppbv), demonstrated excellent capability in reproducing the spatiotemporal variations of HONO, and outperformed an observation-constrained box model incorporated with newly proposed HONO formation mechanisms. Nitrogen dioxide (NO2) was identified as the most impactful features for HONO prediction using the SHapely Additive exPlanation (SHAP) approach, highlighting the importance of NO2 conversion in HONO formation. The DNN model was further employed to predict the future change of HONO levels in different NOx abatement scenarios, which is expected to decrease 27-44% in summer as the result of 30-50% NOx reduction. These results suggest a dual effect brought by abatement of NOx emissions, leading to not only reduction of O3 and nitrate precursors but also decrease in HONO levels and hence primary radical production rates (PROx). In summary, this study demonstrates the feasibility of using deep learning approach to predict HONO concentrations, offering a promising supplement to traditional chemical models. Additionally, stringent NOx abatement would be beneficial for collaborative alleviation of O3 and secondary PM2.5.

Aging of pollution air parcels acts as the dominant source for nocturnal HONO

Atmospheric HONO acts as a major source for OH radicals in polluted areas, playing an important role in formation of secondary pollutants. However, the atmospheric HONO sources remain unclear. Here we propose that the heterogeneous reaction of NO₂ on aerosols during aging processes acts as the dominant source for nocturnal HONO. Based on the nocturnal variations of HONO and related species in Tai'an city of China, we firstly developed new method to estimate the localized HONO dry deposition velocity (v(HONO)). The estimated v(HONO) of 0-0.077 m/s was in a good agreement with the reported ranges. Additionally, we set up a parametrization to reflect the HONO formation from the aged air parcels based on the variation of HONO/NO₂ ratio. The detailed variation of nocturnal HONO could be well reproduced by a complete budget calculation coupled with above parameterizations, with the difference between the observed and calculated HONO levels being <5 %. The results also revealed the average contribution of HONO formation from aged air parcels to atmospheric HONO could achieve to be ~63 % in average.

Dual-energy x-ray absorptiometry scanner mismatch in follow-up bone mineral density testing

Scanner mismatch occurs frequently with follow-up dual-energy x-ray absorptiometry (DXA) scans. Nearly one-in-five follow-up DXA scans were conducted on non-cross-calibrated scanners (scanner mismatch) and more than a quarter of patients who had a follow-up DXA scan had experienced scanner mismatch.

INTRODUCTION

Detecting significant changes in bone mineral density (BMD) with dual-energy x-ray absorptiometry (DXA) scanners relies on the least significant change (LSC). Results from two different DXA scanners can only be compared, albeit with decreased sensitivity for change, if the LSC between the two scanners has been directly determined through cross-calibration. Performing follow-up DXA scans on non-cross-calibrated scanners (scanner mismatch) has safety and economic implications. This study aims to determine the proportion of scanner mismatch occurring at a population level.

METHODS

All patients who completed at least two DXA scans between 1 April 2009 and 31 December 2018 in the province of Alberta, Canada, were identified using population-based health services databases. Scanner mismatch was defined as a follow-up DXA scan completed on a DXA scanner that differed from and was not cross-calibrated to the previous DXA scanner. Multivariate logistic regression models were used to assess predictive factors that may contribute to scanner mismatch.

RESULTS

A total of 264,866 patients with 470,641 follow-up DXA scans were identified. Scanner mismatch occurred in 18.9% of follow-up DXA scans; 28.7% of patients experienced at least one scanner mismatch. Longer duration between scans (OR 1.25, 95% CI 1.24-1.26) and major osteoporotic fracture history before index scan (OR 1.06, 95% CI 1.03-1.08) increased risk of scanner mismatch. Osteoporosis medication use before index scan (OR 0.89; 95% CI 0.88-0.91), recency of follow-up scans (OR 0.98, 95% CI 0.73-0.98), female sex (OR 0.97, 95% CI 0.94-1.00), and age at last scan (OR 0.99, 95% CI 0.99-1.00) were associated with lower risk of scanner mismatch.

CONCLUSION

Scanner mismatch is a common problem, occurring in one-in-five follow-up DXA scans and affecting more than a quarter of patients. Interventions to reduce this large proportion of scanner mismatch are necessary.

Strong impacts of biomass burning, nitrogen fertilization, and fine particles on gas-phase hydrogen peroxide (H2O2)

Gas-phase hydrogen peroxide (H₂O₂) plays an important role in atmospheric chemistry as an indicator of the atmospheric oxidizing capacity. It is also a vital oxidant of sulfur dioxide (SO₂) in the aqueous phase, resulting in the formation of acid precipitation and sulfate aerosol. However, sources of H₂O₂ are not fully understood especially in polluted areas affected by human activities. In this study, we reported some high H₂O₂ cases observed during one summer and two winter campaigns conducted at a polluted rural site in the North China Plain. Our results showed that agricultural fires led to high H₂O₂ concentrations up to 9 ppb, indicating biomass burning events contributed substantially to primary H₂O₂ emission. In addition, elevated H₂O₂ and O₃ concentrations were measured after fertilization as a consequence of the enhanced atmospheric oxidizing capacity by soil HONO emission. Furthermore, H₂O₂ exhibited unexpectedly high concentration under high NO_x conditions in winter, which are closely related to multiphase reactions in particles involving organic chromophores. Our findings suggest that these special factors (biomass burning, fertilization, and ambient particles), which are not well considered in current models, are significant contributors to H₂O₂ production, thereby affecting the regional atmospheric oxidizing capacity and the global sulfate aerosol formation.

Abstract PD5-03: Characterization of high TIL breast cancers reveals a prognostic and functionally distinct tissue-resident memory subpopulation

Background: Tumor infiltrating lymphocytes (TILs) assessed via light microscopy are prognostic and predictive in the early stage and advanced triple negative and HER2-amplified breast cancer (BC). Higher TILs can also identify patients more likely to benefit from anti-PD-1 therapy. In this study we interrogated T cell subsets that comprise high TILs to determine if distinct subpopulations are key mediators of anti-tumor immunity.

Methods: We characterised TILs with a focus on CD3+ T cells in 129 primary and metastatic BC samples using flow cytometry, bulk RNASeq on flow sorted T cell populations, multiplex immunohistochemistry and microdroplet based single cell 3' mRNA sequencing on the 10X Genomics Chromium platform. Cell type specific gene expression signatures were determined from differential expression between putative T cell subpopulations. These signatures were investigated in clinical cohorts, including trial cohorts treated with pembrolizumab.

Results: High TIL Infiltrates consisted primarily of CD3+ T cells, with both CD8 and CD4 populations. Unsupervised clustering of single cell sequencing identified 9 CD8 and CD4 subpopulations with distinct gene expression profiles. In addition to Tregs and CD8 effector memory (TEM) T cells, we found a CD8+ tissue resident memory (TRM) population expressing greater levels of T-cell checkpoints and cytotoxic markers compared to effector memory cells. In 2 primary tumours and 1 liver metastasis, bulk RNASeq of flow sorted TEM and TRM corroborated the single cell mRNASeq results. T cell receptor profiling (TCR) in the 3 samples found non-overlapping repertoires in the 2 primary tumours, but overlap in one metastatic lesion, suggesting divergent developmental origins in the breast, but the potential for nascent TRM differentiation in a metastatic niche. Clustering of these TCRs suggested differing antigen specificities between TRM and non-TRM CD8 T cells. Using Metabric data, the CD8 TRM gene expression signature was prognostic for disease free survival (DFS) in primary TNBCs (n=329, log-rank p=0.003), and was able to further stratify cases with high and low CD8A expression for DFS (log-rank p = 0.03). The CD8 TRM signature was enriched in baseline tumour samples of responders (n = 9) compared with non-responders (n=36) in 45 patients with metastatic melanoma treated with T cell checkpoint blockade (p &lt; 0.0001). Additional single cell sequencing data with TCR sequencing will be combined with these initial results, and an independent data set of single cell mRNASeq and TCR Seq on CD3+ BC TILs will be used to confirm our findings. Cell type specific signatures will be explored in additional clinical cohorts including KEYNOTE-086, and presented at the meeting.

Conclusion: Using single cell profiling of the immune microenvironment in BC we demonstrate that high TIL BCs contain multiple T cell subpopulations with different functional and prognostic significance. Our approach identified a CD8 TRM population with a distinct gene expression profile and strong expression of key immune checkpoints likely representing the presence of true tumor specific immunity. This population may be a key target of immune checkpoint blockade.

Citation Format: Savas P, Virassamy B, Ye C, Salim A, Mintoff CP, Caramia F, Salgado R, Teo ZL, Dushyanthen S, Byrne A, Luen SJ, Fox SB, Speed TP, Mackay LK, Neeson PJ, Loi S. Characterization of high TIL breast cancers reveals a prognostic and functionally distinct tissue-resident memory subpopulation [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD5-03.

AB0864 A nomogram model combining inflammatory factors and MRI radiomics to assess the disease activity of the patients with axSpA in a prospective study

Background

Clinical and magnetic resonance imaging (MRI) disease activity score (DAS) are measuring different aspects of axial spondyloarthritis (axSpA), they are essential in disease activity assessment. The radiomics was on facilitating readings by clinical specialists via enhancing the medical images in which subtle data differences could be distinguished.

Objectives

If the additional information of MRI imaging can be considered as a predictor for axSpA disease activity? In this study, we sought to construct a nomogram integrating the sacroiliac joint (SIJ)- MRI radiomics features and the inflammatory biomarkers to assess disease activity and compare it with clinical disease acitivity index in axSpA patients.

Methods

203 patients data were collected prospectively and confirmed as axSpA were randomly divided into training (n = 143) and validation cohorts (n = 60). 1316 radiomics features were extracted from the 3.0T SIJ-MRI. A Nomogram model was constructed using multivariate logistic regression analysis Incorporating independent clinical factors and radiomics features score (Rad-score). The performance of clinics, Rad-score and nomogram models were evaluated by ROC analysis, calibration curve and decision curve analysis (DCA), and compared with the disease activity index(Ankylosing Spondylitis DAS (ASDAS)-C reactive protein (CRP), ASDAS-erythrocyte sedimentation rate (ESR), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI)) and Spondyloarthritis Research Consortium of Canada (SPARCC) MRI scoring system.

Results

The Rad-score allowed a good discrimination in the training (AUC, 0.91; 95% CI, 0.85-0.96) and the validation cohort (AUC, 0.84; 95% CI, 0.73-0.96). The CRP-radiomics nomogram model also showed favorable discrimination in the training (AUC, 0.96; 95% CI, 0.93-0.99) and the validation cohort (AUC, 0.89; 95% CI, 0.80-0.98), better than BASDAI(AUC, 0.58), ASDAS-CRP(AUC, 0.72), ASDAS-ESR(AUC, 0.77), ESR(AUC, 0.72), CRP(AUC, 0.77) and BASFI(AUC, 0.73), had no statistical difference with SPARCC(AUC, 0.87). Calibration curves and DCA demonstrated the nomogram fit well (p > 0.05) and was useful for activity evaluation.

Conclusion

Rad-score showed good discriminative ability to assess disease activity in axSpA. The nomogram can increase the efficacy for assessment axSpA disease activity, which might simplify clinical evaluation.

Figure 1.

Comparison of ROC curve analyses in prediction models. ROC curves of the clinical features (green curve), radiomics signature model (blue curve), and hybrid model (gold curve) of axSpA in the training cohort (A) and validation cohort (B), respectively. In addition, there are AUC of ASDAS-CRP(pink curve), ASDAS-ESR(brown curve), BASDAI(purple curve), BASFI(azure curve) and SPARCC scoring system(yellow curve) in the validation cohort (B), respectively. AUC: area under the curve; ROC: receiver operating characteristic; SPARCC: Spondyloarthritis Research Consortium of Canada; BASDAI: Bath Ankylosing Spondylitis Disease Activity Index; ASDAS: Ankylosing Spondylitis Disease Activity Score; CRP: C reactive protein; ESR: erythrocyte sedimentation rate; BASFI: Bath Ankylosing Spondylitis Disease Activity Index.

References

[1]Lee KH, Choi ST, Lee GY, Ha YJ, Choi SI. Method for Diagnosing the Bone Marrow Edema of Sacroiliac Joint in Patients with Axial Spondyloarthritis Using Magnetic Resonance Image Analysis Based on Deep Learning. Diagnostics (Basel). 2021;11(7).

[2]Zheng Q, Liu W, Huang Y, Gao Z, Wu Y, Wang X, et al. Predictive Value of Active Sacroiliitis in MRI for Flare Among Chinese Patients with Axial Spondyloarthritis in Remission. Rheumatol Ther. 2021;8(1):411-24.

Acknowledgements

No conflict of interest

Disclosure of Interests

None declared

Induction of immune tolerance in adult rabbits undergoing heterotopic cardiac transplantation

OBJECTIVE

To induce experimental immune tolerance in rabbits and observe its effects on heterotopic cardiac transplantation.

METHODS

Donor's splenic lymphocytes pretreated with platinum metal chelator were injected into the recipient's mesenteric-portal vein. Cyclosporin A was perfused through the donor's heart.

RESULTS

The injection of donor's splenic lymphocytes before transplantation could significantly prolong the survival time of the heterotopically transplanted heart. The effect of two injections was better than that of one. Radioactive tracer studies showed that the 99mTc-HMPAO tagged lymphocytes injected into the recipient rabbit were later concentrated in the liver, though initially they were distributed in multiple organs. The induced immune tolerance was antigen-specific, and it neither affect the other immune functions of the lymphatic system prominently nor exert any harmful effect on the recipient's liver and renal functions. The perfusion of cyclosporin A through the donor heart could block the glycosyl groups, such as D-glucose, D-mannose or N-acetyl-galactosamine on the surface of the myocardial cells, thus might change the antigenic expression, effectively preventing rejection of the graft by the host, and might be considered as a new method to block graft rejection in cardiac transplantation. The combined use of the above-mentioned two methods acted on both the host and the donor, thus reducing the exposed antigens on the donor organ as well as the immune reaction against the donor antigens, and resulting in synergistic effect in inducing immune tolerance in adult rabbits, and resulting in relatively long-term survival of transplanted hearts.

CONCLUSION

This report may provide the experimental basis for inducing immune tolerance in clinical transplantation.

[Analysis of short-term efficacy of perioperative fecal microbiota transplantation combined with nutritional support in patients with radiation-induced enteritis complicated by intestinal obstruction]

Objective: To explore the short-term efficacy of perioperative fecal microbiota transplantation combined with nutritional support in patients with radiation-induced enteritis complicated by intestinal obstruction. Methods: The cohort of this prospective cohort study comprised 45 patients (nine men and 36 women) with radiation-induced enteritis complicated by intestinal obstruction admitted to Shanghai Tenth People's Hospital Affiliated to Tongji University from January 2022 to October 2022. The median age was 53 (42-65) years. Thirty-five of the patients had gynecological tumors and 10 colorectal malignancies. The patients were randomly allocated to a fecal microbiota transplantation group of 20 patients who underwent fecal microbiota transplantation starting 2 weeks before surgery for 6 days, in addition to receiving conventional perioperative treatment, and a conventional treatment group of 25 patients who only received nutritional support during the perioperative period. There were no significant differences in baseline characteristics (sex, age, preoperative nutritional indices, and surgical procedure) between the two groups (all P>0.05). Postoperative recovery (time to passing flatus or a bowel movement, length of stay) and complications were compared between the two groups. Postoperative complications within 30 days after surgery classified in accordance with the international Clavien-Dindo classification of surgical complications (I-V) were statistically analyzed. Improvement in gastrointestinal symptoms, namely abdominal pain, distension, diarrhea, and rectal bleeding) and gastrointestinal quality of life scores (which include 36 problems rated 0-144 points related to physical, psychological, social activities and family life; the lower the score, the more severe the symptoms) were compared between the two groups. Nutritional recovery was assessed by body mass, body mass index, total protein, albumin, prealbumin, and hemoglobin. Results: Compared with the conventional treatment group, the postoperative hospital stay was shorter in the fecal microbiota transplantation group (8.0±4.3 days vs. 11.2±5.4 days, t=2.157, P=0.037) and the time to passage of flatus or having a bowel movement was earlier (2.2±3.2 days vs. 3.9±2.3 days, t=2.072, P=0.044). There were 26 postoperative complications in the fecal microbiota transplantation group and 59 in the conventional treatment group. There were 20 and 36 Grade I to II complications and no and three Grade III to V complications in the transplantation and conventional treatment group, respectively. The overall grade of complication did not differ significantly between the two groups (P=0.544). However, the incidence of postoperative intestinal inflammatory obstruction was lower in the fecal microbiota transplantation than the conventional treatment group (10.0% [2/20] vs. 40.0% [10/25], P=0.040). One patient in the conventional treatment group died. This patient had complete intestinal obstruction complicated by severe malnutrition preoperatively, and an intestinal fistula complicated by abdominal infection postoperatively, and died despite active treatment. Nineteen and 23 patients in the transplantation and conventional treatment group, respectively, attended for follow-up 1 month after surgery; 19 and 21, respectively, attended for follow-up 3 months after surgery, and 17 and 20, respectively, attended for follow-up 6 months after surgery. There were no significant differences between the two groups in abdominal pain or rectal bleeding 1, 3, or 6 months after surgery (all P>0.05). One month after surgery, the incidence of abdominal distension and diarrhea was lower in the fecal microbiota transplantation than in the conventional treatment group (3/19 vs. 48.0% [11/23], P=0.048; 3/19 vs. 52.2% [12/23], P=0.023). However, at the 3 and 6 month follow-ups the incidence of abdominal distension and diarrhea had gradually decreased in both groups and the differences between the groups were not statistically significant (P>0.05 for all). Scores for gastrointestinal quality of life improved significantly in both treatment groups compared with preoperative values (F=71.250, P<0.001; F=79.130, P<0.001, respectively). Scores for gastrointestinal quality of life were higher in the fecal microbiota transplantation than the conventional treatment group at all follow-up time points (P<0.05). One-way ANOVA showed that body mass, body mass index, and total protein, albumin and hemoglobin concentrations improved in both groups compared with preoperative values (all P<0.05). Prealbumin concentration improved significantly in the transplantation (F=5.514, P=0.002), but not in the conventional, group (F=1.535, P=0.211). The improvements in body mass, body mass index, total protein, and albumin were better in the fecal microbiota transplantation than conventional treatment group at 3 and 6 months of follow-up (all P<0.05). Conclusion: Perioperative fecal microbiota transplantation combined with nutritional support is effective in improving early postoperative nutritional status and quality of life in patients with radiation-induced enteritis complicated by intestinal obstruction.

[The research and manufacture of the pneumatic left ventricular assist pump]

The manufacturing methods and testing results of the pneumatic left ventricular assist pump(L-Y pump) are introduced in this paper. The results demonstrate that L-Y pump is reliable, biocompatible and in keeping with the clinical requirements.

Differences in PCV13 Recommendation Practices between Pediatric Care Providers and Primary Care Providers in China: A Cross-Sectional Survey of Behavior and Social Drivers

Objectives: This study examines the recommendation behaviors and influencing factors for the 13-valent Pneumococcal Conjugate Vaccine (PCV13) among 3579 Chinese healthcare workers (HCWs), including 1775 pediatric care providers (Peds-PCPs) and 1804 primary care providers (PCPs). Data were collected from May to July 2023 through a national cross-sectional survey using a structured questionnaire, distributed across hospitals providing pediatric services in five provincial-level administrative divisions. Methods: The sociodemographic data, vaccine knowledge, and recommendation practices were analyzed using Pearson's chi-square test, Wilcoxson rank-sum test, and multivariate logistic regression. Results show that while PCPs are more likely to recommend PCV13, vaccine hesitancy persists among Peds-PCPs. Logistic regression revealed that higher influenza vaccination intention, salary, vaccine consultation frequency, familiarity with immunization, work ethic, and flexible schedules positively impacted HCWs' recommendation behavior. Results: Factors influencing Peds-PCPs' recommendations include vaccine training (OR: 1.470, CI: 1.049-2.509), safety recognition (OR: 1.986, CI: 1.163-3.391), concern over rejection (OR = 1.274, CI: 1.076-1.508) and vaccine cost (OR = 1.203, CI: 1.023-1.414). For PCPs, influencing factors were the perceived susceptibility of children to pneumonia (OR = 2.185, CI: 1.074-4.445), acceptance of herd immunity (OR: 1.717, CI: 1.101-2.677), and belief that parents with better family conditions are more likely to accept vaccine recommendations (OR = 1.229, CI: 1.024-1.477). Conclusion: This survey underscores the need for tailored interventions to address differing perceptions and enhance confidence in the safety and efficacy of vaccines among HCWs, particularly Peds-PCPs.

POS0962 CAN RADIOMICS REPLACE SPARCC SCORING SYSTEM IN EVALUATING BONE MARROW OEDEMA OF THE SACROILIAC JOINTS IN AXIAL SPONDYLOARTHRITIS?

Background

Bone marrow oedema (BMO) of the sacroiliac joints (SIJs) is evaluated to diagnose, classify and monitor disease activity in patients with axial spondyloarthritis (axSpA). Available quantitative methodologies rely on human visual assessment, and errors can’t be completely avoided. Radiomics can extract and select discriminative and quantified features from regions of interest (ROIs), making a more accurate and objective description of BMO.

Objectives

To develop a more objective and efficient method based on radiomics to evaluate BMO of the SIJs by magnetic resonance imaging (MRI) in patients with axSpA in comparison with Spondyloarthritis Research Consortium of Canada (SPARCC) scoring system.

Methods

From September 2013 to July 2021, 523 patients with axSpA underwent 3.0T SIJ-MRI were included, who were randomly classified as training cohort(n=367) and validation cohort(n=156). The optimal radiomics features, selected from the 3.0T SIJ-MRI in the training cohort, were included to build the radiomics model. Four clinical risk predictors were adopted to build the clinical model. The performance of the clinical and radiomics models was evaluated by ROC analysis and decision curve analysis (DCA). Rad-scores were calculated by the radiomics model and SPARCC scores were performed to quantify the BMO of SIJs. We also assessed the correlation between Rad-score and SPARCC score.

Results

The radiomics model, built by 15 optimal features, showed favorable discrimination about SPARCC score <2 or ≥2 both in the training (AUC, 0.91; 95% CI: 0.88-0.94) and the validation cohort (AUC, 0.89; 95% CI, 0.84-0.94). DCA confirmed that the radiomics model was clinically useful. Furthermore, Rad-score has significant correlation with SPARCC score for scoring the status of BMO (rs=0.78, P< 0.001), and moderation correlation for scoring the change (r=0.40, P=0.005).

Conclusion

The radiomics can accurately assess the BMO of the SIJs in axSpA, providing an alternative to SPARCC scoring system. There was a positive correlation between Rad-score and SPARCC score.

References

[1]van der Heijde D, Sieper J, Maksymowych WP, Lambert RG, Chen S, Hojnik M, et al. Clinical and MRI remission in patients with nonradiographic axial spondyloarthritis who received long-term open-label adalimumab treatment: 3-year results of the ABILITY-1 trial. Arthritis Res Ther. 2018;20(1):61.

[2]Landewé RB, Hermann KG, van der Heijde DM, Baraliakos X, Jurik AG, Lambert RG, et al. Scoring sacroiliac joints by magnetic resonance imaging. A multiple-reader reliability experiment. The Journal of rheumatology. 2005;32(10):2050-5.

[3]Cereser L, Zabotti A, Zancan G, Quartuccio L, Cicciò C, Giovannini I, et al. Magnetic resonance imaging assessment of ASAS-defined active sacroiliitis in patients with inflammatory back pain and suspected axial spondyloarthritis: a study of reliability. Clinical and experimental rheumatology. 2021.

[4]Maksymowych WP, Inman RD, Salonen D, Dhillon SS, Williams M, Stone M, et al. Spondyloarthritis research Consortium of Canada magnetic resonance imaging index for assessment of sacroiliac joint inflammation in ankylosing spondylitis. Arthritis Rheum. 2005;53(5):703-9.

[5]Gillies RJ, Kinahan PE, Hricak H. Radiomics: Images Are More than Pictures, They Are Data. Radiology. 2016;278(2):563-77.

Table 1.

Rad-scores corresponding to different SPARCC score intervals about the status of SIJ-BMO.

SPARCC scorenRad-scoreMean(sd)Median (iqr)Range0-1170-1.31(1.64)-1.39(2.16)-6.46, 2.352-61250.73(1.86)0.62(2.12)-3.08, 8.487-11552.25(1.80)2.36(1.79)-1.17, 8.3612-16432.65(2.14)2.66(3.21)-0.76, 7.3917-21383.31(2.05)3.25(2.88)-0.88, 7.5522-26263.08(1.55)3.38(2.12)-1.00, 5.3827-31253.77(1.36)3.77(1.59)0.40, 6.27>31414.10(1.51)4.32(2.28)1.00, 6.96

Disclosure of Interests

None declared

Corrections to the cross-polarization dynamics in solids. The effect of nonsecular terms of heteronuclear dipolar interaction on cross-relaxation

The dynamic theory of cross-polarization in solids is modified by considering the contribution of the nonsecular terms of the heteronuclear dipolar interaction Hamiltonian in the laboratory frame to cross-relaxation. This contribution is evaluated numerically and confirmed experimentally. It is shown that these nonsecular terms may play a considerable role in cross-relaxation in many systems, especially in those with fast internal molecular motion. The complication in the cross-polarization process is further revealed.

[Changes of calcium transport in rat liver nuclei during sepsis]

Calcium transport changes in rat liver nuclei were observed on the model of early sepsis (9 h after operation of cecal ligation and puncture). Calcium content in hepatocytes and nuclei were significantly increased by 20% and 36% respectively (P < 0.05) during sepsis. The activity of Ca(2+)-ATPase in hepatocytic nuclei was increased by 94% (P < 0.01) and 45Ca2+ transport accelerated by 32% (P < 0.01). There was a positive correlation between nuclear 45Ca2+ transport and nuclear Ca(2+)-ATPase activity (r = 0.914, P < 0.01). Calmodulin stimulated the activity of nuclear Ca(2+)-ATPase and 45Ca2+ transport; while calmodulin inhibitor trifluoperazine exerted an opposite effect. The above results suggest that liver nuclear calcium transport is strengthened during early sepsis as a result of changes of Ca(2+)-ATPase activity.

Preliminary studies on tin miners' lung cancer tissue related genes by differential display mRNA

OBJECTIVE

To study the genes related to tin miners' lung cancer tissue.

METHOD

Differential display mRNA.

RESULTS

Thirty cDNA fragments which differentially expressed in lung cancer tissues and the same patient's normal lung tissues were discovered. Among these, 16 expressed in lung cancer tissues, not in normal lung tissues; fourteen expressed on the contrary. Six cDNA fragment sequence was determined. Five sequences CG2, CG7, CG8, CA5 and CC6 had less than 75% homology with known sequences in GenBank BLAST, so they were believed to be new sequences which we have recorded in Genbank. Only one fragment coded CG3 had homology up to 95% with human ribosome protein L27a gene.

CONCLUSIONS

mRNA differential display provides a unique and powerful experimental system to study differential gene expression in tin miners' lung cancer tissues and the same patient's normal lung tissues. Using the system, differential expression of 30 cDNA fragments was observed. Six of them may be used to study the molecular mechanism of miners' radon-associated lung cancer.

The study on related genes in the neoplastic transformation of immortalized human fetal tracheal fibroblast cells induced by irradiation

In this study, we investigated the genes related to the transformation of immortalized human fetal tracheal fibroblast cell line induced by alpha particles by means of differential display mRNA method. The result revealed that there were 23 DNA fragments that were expressed intensively in alphaSHTF cells (SHTF cells forming clone on agar after irradiated by alpha particles emitted by 238Pu) only and not in SHTF (SV40-immortalized human fetal tracheal fibroblast) cells. Northern dot confirmed two fragments, C17-5, C23-1 which showed intensive mRNA expression in alphaSHTF cells, but not in SHTF cells. The length of the C17-5 fragment was 310bp. Searching in BLAST database revealed that the C17-5 fragment might be an unknown sequence.

Improvement of model simulation for summer PM2.5 and O3 through coupling with two new potential HONO sources in the North China Plain

A large fraction of fine particulate matter (PM2.5) and ozone (O3) in the troposphere originates from secondary formation through photochemical processes, which remarkably contributes to the deterioration of regional air quality in China. The photochemical reactions initiated by hydroxyl radicals (OH) play vital roles in secondary PM2.5 and O3 formation. In contrast, the OH levels in polluted areas are underestimated by current chemical transport models (CTMs) because of the strongly unknown daytime sources of tropospheric nitric acid (HONO), which has been recognized as the dominant source of primary OH in polluted areas of China. In this study, the atmospheric HONO levels at two urban sites were found to be significantly underestimated by the WRF-Chem model based on available information on HONO sources. The HONO levels could be well reproduced by the WRF-Chem model after incorporating two new potential HONO sources from the photochemical reactions of NOx, as proposed in our previous study based on chamber experiment results. Comparing the simulations with available information of HONO sources, the simulated levels of atmospheric OH, secondary inorganic and organic aerosols (SIA and SOA), PM2.5 and daily maximum 8-h average (MDA8) O3 were evidently elevated or were closer to the observations over the North China Plain (NCP), with elevation percentages of 0.48-20.1 %, and a decrement percentage of -5.79 % for pNO3-. Additionally, the compensating errors in modeling PM2.5 and the gap in MDA8 O3 levels between observation and simulation in 2 + 26 cities became evidently smaller. The results of this study indicated that the empirical parameterization of two new potential HONO sources through photochemical reactions of NOx improved the model performance in modeling PM2.5 and O3 by narrowing the gap in daytime HONO levels between simulation and observation, although their detailed chemical mechanisms are still unknown and should be further investigated and explicitly parameterized.