湖南省湘资沅澧四大流域管网末梢水中重金属的健康风险评价

目的了解湖南省湘资沅澧流域管网末梢水中八种重金属的污染状况,对其产生的健康风险进行评价。方法本研究对2014年湖南省湘、资、沅、澧流域管网末梢水中砷、镉、六价铬、铅、汞、硒、锰、锌(As、Cd、Cr^(6+)、Pb、Hg、Se、Mn、Zn)的含量进行检测,并进行健康风险评价。结果八种重金属在丰水期和枯水期的含量均未超过国标限值。四大流域中,仅湘江流域的As、Cd和丰水期的Cr^(6+),致癌风险稍高于限值,其余的致癌风险值均小于10^(-4),但四种重金属合计致癌风险在丰水期为1.32×10^(-4),枯水期为1.50×10^(-4),稍高于限值10^(-4)。全流域As、Cd、Cr^(6+)、Hg、Se、Mn、Zn的单独及合计非致癌风险在丰水期和枯水期均小于1。重金属所致非致癌风险和致癌风险在不同水期和不同流域差异有统计学意义(P<0.05)。结论湖南省湘资沅澧流域管网末梢水中重金属的联合污染可能对人群产生健康风险,建议相关地区卫生和环保部门重视四大流域内的重金属污染。     

Effect of Hypoxia on the Muscle Fiber Switching Signal Pathways CnA/NFATc1 and Myostatin in Mouse Myocytes

This study investigated the effects of a CoCl₂-simulated hypoxic environment on the muscle fiber switching signaling pathways calcineurin A/nuclear factor of activated T cells cytoplasmic 1 (CnA/NFATc1) and myostatin. In this study, C2C12 muscle cells were cultured in vitro under CoCl₂-simulated chemical hypoxic conditions, the expression levels of CnA and myostatin were detected through qRT-PCR and Western blot analyses, and a positioning study of NFATc1 was carried out by immunofluorescence labeling. Results showed that CoCl₂ treatment significantly increased the expression levels of CnA and myostatin. Moreover, the position of NFATc1 expression changed; actually, its expression in the nucleus considerably increased. Furthermore, CoCl₂-induced hypoxia inhibited the differentiation of C2C12 cells and reduced the expression levels of many slow- and fast-twitch muscles marker genes, but immunofluorescence staining results showed that the proportion of MyHC I type muscle fiber increased after CoCl₂ treatment. The hypoxic environment simulated by CoCl₂ can activate the signaling pathways CnA/NFATc1 and myostatin and increases the proportion of MyHC I type muscle fibers.     

重离子放射治疗技术及临床应用

重离子的细胞杀伤作用大,有倒转剂量分布优势,而且具有拓展布拉格峰、高传能线密度、高相对生物效应等特点。将其应用于癌症治疗,可使深部区域肿瘤细胞因高剂量辐射而被有效杀灭,而对周围组织因低剂量分布、相对危害较小,能实现精确靶向治疗,这也被认为是最有前景的肿瘤放疗技术。本文简要介绍了重离子放射治疗的物理和生物学特征,回顾了重离子放射治疗的发展历程及现状;重点阐述了重离子放射治疗技术在临床的应用现状及优势,以期为重离子辐射生物学的研究人员提供一定的数据参考和未来方向参考,更好地促进重离子放射治疗在临床治癌中的良好应用。     

Short-term inhalation study of graphene oxide nanoplates

Graphene oxides possess unique physicochemical properties with important potential applications in electronics, pharmaceuticals, and medicine. However, the toxicity following inhalation exposure to graphene oxide has not yet been clarified. Therefore, this study conducted a short-term graphene oxide inhalation toxicity analysis using a nose-only inhalation exposure system and male Sprague–Dawley rats. A total of four groups (15 rats per group) were exposed: (1) control (fresh air), (2) low concentration (0.76?±?0.16?mg/m³), (3) moderate concentration (2.60?±?0.19?mg/m³), and (4) high concentration (9.78?±?0.29?mg/m³). The rats were exposed to graphene oxide for 6?h/day for 5 days, followed by recovery for 1, 3, and 21 days. No significant body or organ weight changes were noted after the short-term exposure or during the recovery period. Similarly, no significant systemic effects of toxicological importance were noted in the hematological assays, bronchoalveolar lavage fluid (BAL) inflammatory markers, BAL fluid cytokines, or blood biochemical assays following the graphene oxide exposure or during the post-exposure observation period. Moreover, no significant differences were observed in the BAL cell differentials, such as lymphocytes, macrophages, or polymorphonuclear cells. Graphene oxide-ingested alveolar macrophages as a spontaneous clearance reaction were observed in the lungs of all the concentration groups from post 1?day to post 21 days. Histopathological examination of the liver and kidneys did not reveal any significant test-article-relevant histopathological lesions. Importantly, similar to previously reported graphene inhalation data, this short-term nose-only inhalation study found only minimal or unnoticeable graphene oxide toxicity in the lungs and other organs.     

参丹活血胶囊联合DP方案治疗不可切除的老年晚期卵巢腺癌的临床研究

目的探讨参丹活血胶囊联合DP方案(多西他赛注射液和顺铂注射液)治疗不可切除的老年晚期卵巢腺癌的临床疗效。方法选取2016年1月—2017年5月绵阳市中心医院收治的不可切除的老年晚期卵巢腺癌患者82例为研究对象,采用随机数字表法将所有患者分为对照组和治疗组,每组各41例。对照组患者给予DP方案治疗,第1天静脉滴注多西他赛注射液,75 mg/m2;第1~3天静脉滴注顺铂注射液,70 mg/m2。治疗组在对照组治疗的基础上口服参丹活血胶囊,6粒/次,3次/d。每个疗程3周,两组患者均连续治疗4个疗程。评价两组患者近期临床疗效,同时比较治疗前后的生活质量评分、免疫功能指标和毒副反应。结果治疗后,对照组和治疗组的客观缓解率分别为60.9%、78.0%,疾病控制率分别为43.9%、58.5%,两组近期临床疗效比较差异有统计学意义(P0.05)。治疗后,两组功能状况评分、社会状况评分均显著升高,附加关注评分、情感状况评分、生理状况评分均显著降低,同组治疗前后比较差异具有统计学意义(P0.05);且治疗后治疗组生活质量评分改善情况明显优于对照组,两组比较差异具有统计学意义(P0.05)。治疗后,治疗组免疫球蛋白G(IgG)、免疫球蛋白M(IgM)、免疫球蛋白A(IgA)、CD3~+和CD4~+均显著增高,同组治疗前后比较差异具有统计学意义(P0.05);且治疗后治疗组免疫指标明显高于对照组,两组比较差异具有统计学意义(P0.05)。治疗期间,治疗组各项毒副反应发生率均显著低于对照组,两组比较差异具有统计学意义(P0.05)。结论参丹活血胶囊联合DP方案治疗不可切除的老年晚期卵巢癌具有较好的临床疗效,能够有效改善患者生活质量和免疫功能,毒副作用小,具有一定的临床推广应用价值。     

Parametric models for biomarkers based on flexible size distributions

Recent advances in social science surveys include collection of biological samples. Although biomarkers offer a large potential for social science and economic research, they impose a number of statistical challenges, often being distributed asymmetrically with heavy tails. Using data from the UK Household Panel Survey, we illustrate the comparative performance of a set of flexible parametric distributions, which allow for a wide range of skewness and kurtosis: the four‐parameter generalized beta of the second kind (GB2), the three‐parameter generalized gamma, and their three‐, two‐, or one‐parameter nested and limiting cases. Commonly used blood‐based biomarkers for inflammation, diabetes, cholesterol, and stress‐related hormones are modelled. Although some of the three‐parameter distributions nested within the GB2 outperform the latter for most of the biomarkers considered, the GB2 can be used as a guide for choosing among competing parametric distributions for biomarkers. Going “beyond the mean” to estimate tail probabilities, we find that GB2 performs fairly well with some disparities at the very high levels of glycated hemoglobin and fibrinogen. Commonly used linear models are shown to perform worse than almost all the flexible distributions.     

急性缺血性卒中患者白细胞计数水平及其与短期预后不良关系

目的了解急性缺血性卒中患者白细胞计数水平及其与短期预后不良的关系,为急性缺血性卒中的预防控制提供参考依据。方法于2015年1月1日—2015年8月31日在中国医科大学附属第一医院鞍山医院、丹东市第一医院、辽阳县医院和大洼县医院采用回顾性队列研究方法收集1 591例急性缺血性卒中患者,分析其白细胞计数水平及其与短期预后不良的关系。结果本次调查的1 591例急性缺血性卒中患者改良Rankin量表(m RS)得分为(1.47±1.79)分;其中,无残疾组患者1 219例(76.6%),残疾组患者284例(17.9%),死亡患者88例(5.5%);共372例患者(23.4%)为短期预后不良。在控制了性别、年龄、缺血性脑卒中病史和胱抑素C水平等混杂因素后,多因素非条件logistic回归分析结果显示,白细胞计数为6.50×10~9/L^8.09×10~9/L和≥8.10×10~9/L急性缺血性卒中患者短期预后不良的发生风险分别为白细胞计数<5.30×10~9/L患者的2.382倍(OR=2.382,95%CI=1.445~3.925)和2.531倍(OR=2.531,95%CI=1.574~4.069)。结论白细胞计数水平是急性缺血性卒中患者短期预后不良的独立危险因素。     

影像设备学X线课程中雨课堂的翻转课堂混合式教学模式的应用

目的探讨基于雨课堂的翻转课堂混合式教学模式在影像设备学X线课程中的应用效果。方法选取开设医学影像设备学课程学生135名,随机分成传统教学组、翻转课堂联合传统教学组、基于雨课堂的翻转课堂联合传统教学组,每组45名。每个组别使用相应的教学方式,结束教学后,通过调查问卷及理论知识测验等形式对教学效果进行评价。结果基于雨课堂的翻转课堂联合传统教学组理论成绩高于翻转课堂教学组、传统教学组,差异有统计学意义(P<0.05)。基于雨课堂的翻转课堂联合传统教学组、翻转课堂教学组理论成绩均高于传统教学组,差异有统计学意义(P<0.05)。结论基于雨课堂的翻转课堂的混合式教学模式在影像设备学X线课程教学中应用有良好的效果。     

Heavy ion and X-ray irradiation alter the cytoskeleton and cytomechanics of cortical neurons

Heavy ion beams with high linear energy transfer exhibit more beneifcial physical and biological performance than conventional X-rays, thus improving the potential of this type of radiotherapy in the treatment of cancer. However, these two radiotherapy modalities both cause inevitable brain injury. The objective of this study was to evaluate the effects of heavy ion and X-ray irra-diation on the cytoskeleton and cytomechanical properties of rat cortical neurons, as well as to determine the potential mechanism of neuronal injury after irradiation. Cortical neurons from 30 new-born mice were irradiated with heavy ion beams at a single dose of 2 Gy and X-rays at a single dose of 4 Gy;subsequent evaluation of their effects were carried out at 24 hours after irradiation. An immunolfuorescence assay showed that after irradiation with both the heavy ion beam and X-rays, the number of primary neurons was signiifcantly decreased, and there was ev-idence of apoptosis. Radiation-induced neuronal injury was more apparent after X-irradiation. Under atomic force microscopy, the neuronal membrane appeared rough and neuronal rigidity had increased. These cell changes were more apparent following exposure to X-rays. Our ifnd-ings indicated that damage caused by heavy ion and X-ray irradiation resulted in the structural distortion and rearrangement of the cytoskeleton, and affected the cytomechanical properties of the cortical neurons. Moreover, this radiation injury to normal neurons was much severer after irradiation with X-rays than after heavy ion beam irradiation.