Effects of GM-CSF, IL-3, and GM-CSG/IL-3 fusion protein on apoptosis of human myeloid leukemic cell line Tf-1 induced by irradiation

AIM: To observe the effects of three cytokines on the apoptosis of Tf-1 cells induced by y irradiation and investigate the relationship between apoptosis and caspase-3 activity. METHODS: Different cytokines GM-CSF, IL-3 and GM-CS/IL-3 fusion protein were added into the irradiated Tf-1 cells. MTT assay, morphology, flow cytometry, and DNA fragmentation assay were used to observe the effects of cytokines on apoptosis. The caspase-3 activity was determined with a fluorocytometer. RESULTS: Irradiated Tf-1 cells showed typical morphological characteristic of apoptosis demonstrated by transmission electron microscopy and were accumulated in G0/G1 phase. In the groups treated with growth factors after irradiation, three cytokines significantly increased the viability rate, distinctly decreased the apoptosis rate and the proportion of DNA fragmentation. When Tf-1 cells were irradiated by y     

低剂量辐射对Lewis肺癌小鼠肿瘤微环境的影响

目的 探讨低剂量辐射(LDR)对Lewis肺癌小鼠肿瘤微环境(TME)的影响,以及高剂量辐射(HDR)前LDR预处理在TME中发挥的效应机制.方法 接种Lewis肺癌细胞(1×106)于雄性C57BL/6小鼠左侧腋下,待小鼠肿瘤直径1 cm左右(12 d),随机分为假手术Sham(1)组、LDR(2)组、HDR(3)组...     

第三代双源CT在心律不齐冠脉CTA检查中的应用价值

目的 探索第三代双源CT在心律不齐患者冠状动脉CT血管造影(CT angiography,CTA)扫描过程中的应用.方法 选择本院收治的心律不齐患者96例,随机分为对照组和观察组进行CTA扫描,各48例.对照组给予第一代双源CT上行常规CT技术进行检查,观察组给予第三代双源CT上行低管电压、低剂量碘造影剂的双低技术进行...     

Phloroglucinol (PG) purified from Ecklonia cava attenuates radiation-induced apoptosis in blood lymphocytes and splenocytes

Phloroglucinol (PG), a polyphenol compound of Eckloniacava known as brown algae abundant in Jeju island, has been proposed to exert the antioxidative and cytoprotective effects against oxidative stress. In this study, we confirmed that PG protected mice from damages caused by ionizing radiation and investigated its protection mechanism in detail. The result showed that PG increased the viability of splenocytes without cytotoxicity. Also, PG significantly enhanced the proliferation of splenocytes by limiting the increment of sub-G₁ DNA contents via the inhibition of reactive oxygen species production in 2 Gy-irradiated splenocytes. In addition, PG significantly decreased DNA damage and the number of apoptotic fragments in lymphocytes against oxidative stress. Also, PG increased the counts of endogenous spleen CFUs, compared with only ionizing radiation-irradiated mice. These results demonstrate the multi-faceted protection mechanisms of PG in mice against oxidative stress caused by ionizing radiation, providing the benefit of inhibiting apoptosis and strengthening hematopoiesis.     

华蟾素配合立体定向放射治疗中晚期食管癌28例

目的观察华蟾素配合立体定向伽玛射线放射治疗中晚期食管癌的近期临床疗效。方法将56例患者随机均分为华蟾素联合伽玛刀治疗组（治疗组）和伽玛刀单独治疗组（对照组）。伽玛刀治疗总剂量40～50Gy,次数10～12次,边缘剂量300～420cGy,等剂量曲线55%～85%,每日治疗1次;治疗组加用华蟾素注射液20～30mL静脉滴注,1次/d,连续3～4周。结果 56例患者均顺利完成治疗,治疗组梗阻症状总缓解率、影像学总缓解率均显著高于对照组（P均小于0.05）;治疗组不良反应如急性放射性食管炎、白细胞下降发生率虽低于对照组,但差异无统计学意义（P〉0.05）。结论华蟾素注射液联合伽玛射线立体定向放射治疗中晚期食管癌患者,临床症状缓解率高,毒副作用小,患者耐受性好,近期疗效令人满意。     

Solid cancer incidence among Chinese medical diagnostic x‐ray workers, 1950–1995: Estimation of radiation‐related risks

The objective of this study was to estimate solid cancer risk attributable to long‐term, fractionated occupational exposure to low doses of ionizing radiation. Based on cancer incidence for the period 1950–1995 in a cohort of 27,011 Chinese medical diagnostic X‐ray workers and a comparison cohort of 25,782 Chinese physicians who did not use X‐ray equipment in their work, we used Poisson regression to fit excess relative risk (ERR) and excess absolute risk (EAR) dose–response models for incidence of all solid cancers combined. Radiation dose reconstruction was based on a previously published method that relied on simulating measurements for multiple X‐ray machines, workplaces and working conditions, information about protective measures, including use of lead aprons, and work histories. The resulting model was used to estimate calendar year‐specific badge dose calibrated as personal dose equivalent (Sv). To obtain calendar year‐specific colon doses (Gy), we applied a standard organ conversion factor. A total of 1,643 cases of solid cancer were identified in 1.45 million person‐years of follow‐up. In both ERR and EAR models, a statistically significant radiation dose–response relationship was observed for solid cancers as a group. Averaged over both sexes, and using colon dose as the dose metric, the estimated ERR/Gy was 0.87 (95% CI: 0.48, 1.45), and the EAR was 22 per 10⁴PY‐Gy (95% CI: 14, 32) at age 50. We obtained estimates of the ERR and EAR of solid cancers per unit dose that are compatible with those derived from other populations chronically exposed to low dose‐rate occupational or environmental radiation.     

高温联合辐射对仔鼠神经系统与行为的影响

目的探讨高温联合辐射对仔鼠神经系统与行为的影响。方法将130只孕鼠按随机抽签法分为13组,每组10只。在孕鼠妊娠第8、9d分别接受60Co及γ-射线全身照射各1次,照射剂量1．0Gy;第10d各置温箱中,分别使其肛温保持在37、±0．5℃,41±0．5℃,42±0．5℃,并持续3、4、5min。移出温箱2h后,每组随机取5只,单笼饲养,待其自然分娩,观察仔鼠体格发育、生理发育、神经反射、活动能力等神经行为指标。结果孕鼠经高温联合辐射后,其仔鼠的生理发育、早期反射、感觉功能、活动能力均显著滞后于对照组(P<0．01)。结论高温联合辐射具有复合作用,可增强对仔鼠神经系统的不良影响。