Objective To examine the application of On-Board Imaging (OBI) system-based image-guided radiotherapy (IGRT) in the improvement of the precision of intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma.Methods Ten patients with nasopharyngeal carcinoma were treated with IMRT using the OBI system. The IGRT images after positioning, position adjustment, and treatment were observed and recorded to investigate the image difference between CT simulation and IGRT. Results The deviations in the x (lateral), y (cranial-caudal), and z (ventral-dorsal) directions between CT simulation and IGRT images were 0.22±1.00 mm,-0.37±1.28 mm, and 0.04±1.36 mm, respectively, after positioning, 0.29±0.76 mm,-0.04±0.78 mm, and -0.01±0.92 mm, respectively, after position adjustment, and 0.20±0.78 mm, 0.16±0.80 mm, and 0.05±0.92 mm, respectively, after treatment. The probabilities of a ≤1 mm deviation in the x, y, and z directions were 81.0%, 77.6%, and 88.2%, respectively, after positioning, 92.5%, 96.4%, and 96.4%, respectively, after position adjustment, and 91.7%, 94.9%, and 96.8%, respectively, after treatment. Conclusions The application of OBI system-based IGRT is very important in the improvement of the precision of fractionated IMRT for patients with nasopharyngeal carcinoma. The position of the patient should be adjusted based on the IGRT image after positioning in order to correct set-up error and effectively increase the precision of fractionated IMRT.

BACKGROUND: Ultrasonic coupling agent is indispensable in ultrasonic imaging. The service life and change frequency of the ultrasonic probe is determined by the internal coupling agent of the chosen hydrogel material. Due to defects in the existing gel-formula, after a period of time in use it can cause the surface depression of probes and thus influence the ultrasonic imaging quality. OBJECTIVE: To optimize the gel formula of the coupling agent. METHODS: The amplified synthesis process of polyacrylamide hydrogel was optimized by changing the ratio of monomer concentration to N, N-methylenebisacrylamide crosslinker in the synthesis conditions, and the factors influencing its acoustic properties were explored to meet the technical requirements in the clinical use process. RESULTS AND CONCLUSION: When the monomer concentration was set to 70 g/L and the mass ratio of monomer to crosslinker was 7:1, the polyacrylamide hydrogel was in the best state. The obtained polyacrylamide hydrogel had a stable swelling rate, had a strong ability to keep water and make the volume reduce under the influence of the operating temperature of ultrasound, and its relative amplitude changed less with the change of ultrasonic frequency. The sound attenuation coefficient of polyacrylamide hydrogel would be higher when the frequency of ultrasonic sound source was higher. The changes of monomer concentration would have significant impacts on the acoustic properties of polyacrylamide hydrogel. Therefore, by controlling the monomer concentration ratio, we can prepare the coupling agent that exhibits relatively stable acoustic properties at an optimum concentration and achieves an optimal imaging effect.

Endoplasmic reticulum (ER) stress is mediated by disturbance of Ca²⁺ homeostasis. The store-operated calcium (SOC) channel is the primary Ca²⁺ channel in non-excitable cells, but its participation in agent-induced ER stress is not clear. In this study, the effects of tunicamycin on Ca²⁺ influx in human umbilical vein endothelial cells (HUVECs) were observed with the fluorescent probe Fluo-4 AM. The effect of tunicamycin on the expression of the unfolded protein response (UPR)-related proteins BiP and CHOP was assayed by western blotting with or without inhibition of Orai1. Tunicamycin induced endothelial dysfunction by activating ER stress. Orai1 expression and the influx of extracellular Ca²⁺ in HUVECs were both upregulated during ER stress. The SOC channel inhibitor SKF96365 reversed tunicamycin-induced endothelial cell dysfunction by inhibiting ER stress. Regulation of tunicamycin-induced ER stress by Orai1 indicates that modification of Orai1 activity may have therapeutic value for conditions with ER stress-induced endothelial dysfunction.
Blotting, Western ; Calcium ; Endoplasmic Reticulum ; Endoplasmic Reticulum Stress ; Endothelial Cells ; Homeostasis ; Human Umbilical Vein Endothelial Cells ; Tunicamycin ; Unfolded Protein Response

Objective: To investigate the value of combined stool syndecan-2 (SDC2) and tissue factor pathway inhibitor 2 ( TFPI2) gene methylation testing in the early screening of colorectal cancer． Methods : 106 patients with colorectal cancer (colorectal cancer group) ，75 patients with advanced adenoma ( advanced adenoma group) and 35 patients with non-advanced adenoma (non-advanced adenoma group) were selected as study subjects，and 153 patients with other gastrointestinal disorders and 182 patients with negative colonoscopy results during the same period were selected as the control group．The quantitative methylation-specific PCR(qMSP) method was used to detect SDC2 and TFPI2 gene methylation in the stool specimens of all subjects．The sensitivity and specificity of the combined SDC2 and TFPI2 gene methylation assay for the detection of colorectal cancer and adenoma were evaluated using colonoscopy and pathology results as the gold standard. Results : Among 106 patients with colorectal cancer， the sensitivity of combined methylation test was 93. 4% ; among 75 patients with advanced adenoma，the sensitivity of combined methylation test was 62. 7% ; among 35 patients with non-advanced adenoma，the sensitivity of combined methylation test was 34. 3% ; the specificity of the combined SDC2 and TFPI2 gene methylation test for colorectal cancer and adenoma screening was 94. 6%． Conclusion The combined SDC2 and TFPI2 gene methylation test has high sensitivity for colorectal cancer and its early lesions，and it also maintains high specificity.

Objective: To compare the predictive efficacy of the two thrombosis risk assessment scores (Padua and IMPEDE scores) in venous thromboembolism (VTE) within 6 months in patients with newly diagnosed multiple myeloma (NDMM) in China. Methods: This study reviewed the clinical data of 421 patients with NDMM hospitalized in Beijing Jishuitan Hospital from April 2014 to February 2022. The sensitivity, specificity, accuracy, and Youden index of the two scores were calculated to quantify the thrombus risk assessment of VTE by the Padua and IMPEDE scores. The receiver operating characteristics curves of the two evaluation scores were drawn. Results: The incidence of VTE was 14.73%. The sensitivity, specificity, accuracy, and Youden index of the Padua score were 100%, 0%, 14.7%, and 0% and that of the IMPEDE score was 79%, 44%, 49.2%, and 23%, respectively. The areas under the curve of Padua and IMPEDE risk assessment scores were 0.591 and 0.722, respectively. Conclusion: IMPEDE score is suitable for predicting VTE within 6 months in patients with NDMM.
Humans ; Venous Thromboembolism/etiology* ; Multiple Myeloma/diagnosis* ; Risk Assessment ; Risk Factors ; ROC Curve ; Retrospective Studies