The Effect of Hypoxia on Relative Biological Effectiveness and Oxygen Enhancement Ratio for Cells Irradiated with Grenz Rays

Development of a silicone-based radio-fluorogenic dosimeter using dihydrorhodamine 6G

A silicon-based three-dimensional dosimeter can be formed in a free shape without a container and deformed because of its flexibility. Several studies have focused on enhancing its radiological characteristics and assessing its applicability as a quality assurance tool for image-guided and adaptive radiation therapy, considering motion and deformation. Here, we applied a fluorescence probe (dihydrorhodamine 6G, DHR6G) to a silicon elastomer as a new radiosensitive compound that converts nonfluorescent into fluorescent dyes using irradiation, and its fluorescence intensity increases linearly with the absorbed dose. In this study, we demonstrated a cost-effective synthesis method and optimized the composition conditions. The results showed that the DHR6G-SE prepared from 2.2 × 10-3 wt% DHR6G, 0.024 wt% pyridine, and a silicone elastomer (SE) (SILPOT TM 184, base/curing agent = 10/1) exhibited a linear increase in fluorescence with radiation exposure within a dose range of 0-8 Gy and a highly stable sensitivity for as long as 64 h. To demonstrate its container-less characteristics, the possibility of dosimetry for low-energy X-rays using DHR6G-SE was investigated.

Effect of Hematocrit Injury on the Survival Rate of Advanced Malignant Tumors and Its Clinical Significance

Objective

To investigate the effect of logistic multivariate analysis on the survival rate of advanced malignant tumors and to evaluate the effect of erythrocyte storage injury on the survival rate of advanced malignant tumors and its clinical significance.

Methods

A retrospective analysis was performed on 120 advanced cancer patients who received blood transfusion in Shaanxi Cancer Hospital from March 2018 to June 2019, and the risk factors for death were analyzed. A total of 72 advanced cancer patients admitted to hospital from March 2019 to June 2021 were included in the study. The patients with red blood cell transfusion storage time ≤ 14 d were the study group (n = 36), and the patients with red blood cell transfusion storage time > 14 d were the control group (n = 36). Compare the total efficiency of blood transfusion. The levels of Hb, erythrocyte count, hematocrit (HCT), blood oxygen saturation (SPO2), creatinine (Cr), erythrocyte deformability index, whole blood, erythrocyte, and hemoglobin before and after blood transfusion were compared, and the adverse reactions of blood transfusion were recorded.

Results

Dyspnea and delirium were significantly associated with patient survival time (P < 0.05). Red blood cell storage time ≤ 14 days, Lym% < 12%, lactate dehydrogenase (LDH) > 500 U/L, and ALB < 30 g/L were significantly correlated with survival time. Karnofsky performance status (KPS) < 30, delirium, LDH > 500 U/L, and albumin (ALB) < 30 g/L were independent influencing factors of survival (P < 0.05). The overall effective rate of the research group was higher (P < 0.05). The incidence of adverse reactions in the study group was lower (P < 0.05). The levels of Hb, red blood cell count, and HCT in the study group were higher (P < 0.05). Compared with the control group, the SPO2 level and the red blood cell deformability index were higher in the study group (P < 0.05). After blood transfusion, the level of (diphosphoglycerate) DPG in the study group was higher than that in the control group (P < 0.05). The length of hospital stay in the study group was significantly shortened (P < 0.05). The nosocomial infection rate and case fatality rate in the study group were significantly reduced (P < 0.05).

Conclusion

Red blood cell storage time ≤ 14 d, LYM% < 12%, LDH > 500 U/L, and ALB < 30 g/L are all significantly correlated with survival time. KPS < 30, delirium, LDH > 500 U/L, and ALB < 30 g/L were independent factors for survival (P < 0.05). Transfusion of red blood cells stored for ≤14 days in patients with advanced malignant tumors can significantly increase the effective infusion rate, improve anemia status, shorten hospital stay, and reduce mortality and risk of nosocomial infection and is worthy of clinical promotion.