Monte Carlo simulations of dose distributions with necrotic tumor targeted radioimmunotherapy

Radio-resistant hypoxic tumor cells are significant contributors to the locoregional recurrences and distant metastases that mark failure of radiotherapy. Due to restricted tissue oxygenation, chronically hypoxic tumor cells frequently become necrotic and thus there is often an association between chronically hypoxic and necrotic tumor regions. This simulation study is the first in a series to determine the feasibility of hypoxic cell killing after first targeting adjacent areas of necrosis with either an α- or β-emitting radioimmunoconjugate.     

Interrelationships between changes in erythropoietin,plasma volume,haemoglobin concentration,and total haemoglobin mass in endurance athletes

Interrelationships between physiological changes (Δ) in erythropoietin (EPO), plasma volume (PV), haemoglobin concentration ([Hb]), and total haemoglobin mass (tHb-mass) were examined in cyclists who trained in different altitudes. Regardless of differences in pattern of changes observed in three training locations, ΔEPO was correlated positively with ΔPV, negatively with Δ[Hb], and trivially with ΔtHb-mass. Δ[Hb] was negatively correlated with ΔPV. In the pooled data the Spearman’s rank correlation coefficients were as follows: r = 0.783, P < 0.001; r = ?0.704, P < 0.001; r = 0.136, P > 0.05; r = ?0.813, P < 0.001, respectively. The obtained results have shown that EPO does not only regulate [Hb] by erythropoiesis stimulation but also by PV modulation, which probably aims at keeping proper level of arterial oxygen content for oxygen delivery to tissues.     

补充马齿苋复合溶液对常温高湿环境下男子轮滑运动员赛前训练期间体成分和内环境的调控作用

目的:研究马齿苋复合溶液对常温高湿环境下男子轮滑运动员赛前训练期间体成分和内环境的调控作用。方法:沈阳师范大学冰雪轮滑俱乐部12名男队员随机分为对照组和实验组,每组6人。赛前常温高湿环境下[训练场所温度(23.43±1.61)℃,湿度(81.36±4.36)%]训练2周后,实验组每日按1.5 ml/kg剂量服用马齿苋复合溶液1次,连续10天,对照组服用等量安慰剂。分别于训练前1天、训练1周翌日、训练2周翌日、干预后翌日上午10时监测体重、去脂体重、水分和蛋白质等体成分指标。分别于干预前(训练2周翌日)和干预后翌日早6时留取晨尿、空腹肘静脉抽血测定尿比重、尿pH、血尿素、血肌酐和血尿酸含量。结果:(1)体重、去脂体重、水分和蛋白质:赛前训练2周后对照组和实验组均显著低于训练前(P<0.05),但两组间比较均无显著差异(P>0.05)。干预后实验组显著高于对照组(P<0.05)。(2)尿比重、尿pH、血尿素、血肌酐和血尿酸:干预前两组无显著差异(P>0.05),干预后实验组明显低于对照组(P<0.05)。结论:补充马齿苋复合溶液对常温高湿环境下男子轮滑运动员赛前训练引起的体成分和内环境的负向改变有确切的调控作用。     

Effects of the menstrual cycle on body composition

Fluctuations in regulatory hormones, body temperature and other physiological mechanisms during the menstrual cycle cause individual symptoms, including a perceived weight gain. This study determined the effects of a normal menstrual cycle on body weight, percentage body fat (% fat by hydrostatic weighing), respiratory measures of vital capacity and residual volume by spirometry, and the sum of 7 skinfolds (triceps, subscapula, axilla, chest, suprailium, abdomen and thigh). Twenty regularly menstruating (23- to 35-d cycles) subjects (aged 20–30 years) volunteered for this study. Measures were duplicated on days 1, 7, 14, 21 and 28 after the onset of menstrual flow. Repeated-measures analysis of variance indicated no significant differences for any measured parameter between the 5 assigned days. Therefore, body composition in this age group was not affected by normal menstruation.     

CT、MRI在眼眶炎性假瘤的诊断价值

目的:探讨CT和MRI对眼眶炎性假瘤的诊断和鉴别诊断价值。方法:回顾性分析经临床、病理证实的63例眼眶炎性假瘤的影像学表现。结果:根据病变累及部位及形态学表现分为:①隔前型2例,表现为眼睑肿胀;②巩膜周围炎型1例,表现为眼球壁增厚;③视神经束膜炎型3例,表现为视神经增粗;④弥漫型10例,病变可同时累及眶隔前组织、眼肌、视神经、眼环、泪腺、眶内脂肪或眶周组织;⑤肿块型12例,表现为边界清楚的肿块;⑥泪腺炎型9例,表现为泪腺肿大;⑦肌炎型26例,表现为1条或数条眼外肌增粗、肥大。结论:CT和MRI能对眼眶炎性假瘤确切定位及分型,为临床治疗方案提供重要依据,二者的结合极大地提高了眼眶炎性假瘤的正确诊断率。     

429名军队在职和离退休干部血脂水平调查分析

目的调查分析我院在职和离退休干部血脂状况,阐明健康的生活方式和饮食结构对防治高脂血症的意义。方法对比分析300例在职干部与129例离退休干部的血清总胆固醇水平及甘油三酯水平,并调查他们的生活方式、饮食结构等状况。结果在职干部的甘油三酯水平明显高于离退休干部组(P<0.05),两组总胆固醇水平的差异无显著性。结论健康的生活方式和饮食结构及药物治疗对防治高脂血症、控制动脉粥样硬化和冠心病有重要意义。     

不同年龄、性别体检人群人体组成成分对比分析

目的探讨人体组成成分指标在不同年龄性别间的差异,为更精准的个体化营养及运动管理提供依据。方法选取成年健康体检受检者1 656名,按年龄分为6组:18~29岁组(n=79),30~39岁组(n=346),40~49岁组(n=463),50~59岁组(n=471),60~69岁组(n=236),70岁以上组(n=61)。采用In Body 720人体成分分析仪生物电阻抗法检测人体组成成分。结果不同性别者腰臀比,身体水分、蛋白质、矿物质含量,体脂百分比,肌肉量,基础代谢率的分布不同(P<0.05),体质量指数、健康评估得分无差异(P>0.05)。不同年龄组比较发现,男性身体水分含量分布无差异(P>0.05),其余各指标分布有差异(P<0.05);而女性各指标分布均有差异(P<0.05)。基础代谢率在18~39岁间随年龄增长而增高,40岁之后开始下降。体质量指数在18~59岁间随年龄增长而增高,60岁后开始降低。蛋白质、肌肉量、健康评估得分均在50岁之后呈现下降趋势。女性矿物质、肌肉量及身体水分含量随年龄增加而减少,且早于男性。体脂百分比及腰臀比值均随年龄增长而增长,女性增长速度快于男性。结论不同年龄、性别成年受检者人体成分指标有差异。40岁以前是体质量控制的重要年龄段。40岁以后,应随基础代谢率降低而减少能量摄入。女性较男性应更早重视维持机体蛋白质、矿物质含量,增肌减脂,应特别关注腰部减脂。     

气相色谱法测定新疆金鸡菊多糖中单糖的组成

目的采用柱前衍生气相色谱法测定新疆金鸡菊多糖中单糖的组成。方法金鸡菊粗多糖经三氟乙酸水解后,采用糖腈乙酸酯衍生化方法,利用DM-5石英毛细管色谱柱(30 m×0.25 mm,0.25μm)对金鸡菊多糖中的6种单糖衍生物进行分离测定,6种单糖全部达到基线分离,总分析时间为45 min。用保留时间定性,外标法定量。方法线性范围为0.6～10 mg/ml,各标准曲线相关系数r>0.9995;加样回收率为101.5%～103.4%。结果金鸡菊粗多糖由鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖和半乳糖组成,摩尔比为0.42∶2.51∶0.48∶0.83∶6.38∶2.07。结论气相色谱法测定新疆金鸡菊多糖中单糖的组成具有简单、快速、分离效率高等特点,确定了新疆金鸡菊中单糖组成及其摩尔比,可为新疆金鸡菊的研究提供参考。     

驻东南某地区部队尿石症尿石成分分析

目的：研究驻东南某部队尿石成分及分布特征。方法：采用红外光谱法定性定量方法对驻东南某地区部队238例尿石进行化学成分分析研究。结果：含钙尿结石88．23％,含草酸钙结石85．29％,纯草酸钙结石39．50％,尿酸结石11．77％,混合性结石以草酸钙和磷酸钙结石最常见（33．61％）。结论：尿石成分分析对尿石症的病因探讨和防治可提供重要线索。     

Optimising training adaptations and performance in military environment

Objectives

Worldwide decreases in physical fitness and increases in body fat among youth have set challenges for armed forces to recruit physically capable soldiers. Therefore, knowledge of optimizing physical adaptation and performance through physical training is vital. In addition, maintaining or improving physical performance among professional soldiers in various military environments is crucial for overall military readiness. The present review focuses on the effects of military training on physical performance by searching for optimal methods to do it.

Dose perturbation due to catheter materials in high-dose-rate interstitial 192Ir brachytherapy

PurposeCatheters made of either metal or plastic are currently used in brachytherapy treatment to insert radiative sources into patients. However, the radiation dose perturbations due to catheter attenuation are not taken into account in treatment planning. The purpose of this work is to quantify the effects of catheter composition on dose distribution and study their impacts on the overall treatment with high-dose-rate ¹⁹²Ir sources.Methods and MaterialsDose perturbations are first studied in a simplified case consisting of two parallel catheters. The catheter wall is either composed of stainless steel or polyoxymethylene. The attenuations are studied as the distance between the two catheters is varied from 5 to 30 mm. Dose perturbations resulting from irradiation are evaluated with a Monte Carlo GEANT4 dose calculation algorithm. The dose differences are further investigated with seven typical high-dose-rate prostate treatment plans involving 17 catheters.ResultsThe dose differences compared with water in the simplified case reach −4.3 ± 0.1% for stainless steel and 1.7 ± 0.5% for polyoxymethylene at 10 mm above the source when the catheters are separated by a distance of 5 mm. Dose perturbations are reduced in real treatment plans because of the contributions of the many dwell positions. Stainless steel and polyoxymethylene catheters induce on an average a dose difference of −1.3 ± 0.3% and 0.1 ± 0.2%, respectively in the target.ConclusionsThe dose differences reported in this work do not warrant any changes in the clinical procedures.     

Automated quantification of muscle and fat in the thigh from water-, fat-, and nonsuppressed MR images

Purpose:

To introduce and validate an unsupervised muscle and fat quantification algorithm based on joint analysis of water‐suppressed (WS), fat‐suppressed (FS), and water and fat (nonsuppressed) volumetric magnetic resonance imaging (MRI) of the mid‐thigh region.

Materials and Methods:

We first segmented the subcutaneous fat by use of a parametric deformable model, then applied centroid clustering in the feature domain defined by the voxel intensities in WS and FS images to identify the intermuscular fat and muscle. In the final step we computed volumetric and area measures of fat and muscle. We applied this algorithm on datasets of water‐, fat‐, and nonsuppressed volumetric MR images acquired from 28 participants.

Results:

We validated our tissue composition analysis against fat and muscle area measurements obtained from semimanual analysis of single‐slice mid‐thigh computed tomography (CT) images of the same participants and found very good agreement between the two methods. Furthermore, we compared the proposed approach with a variant that uses nonsuppressed images only and observed that joint analysis of WS and FS images is more accurate than the nonsuppressed only variant.

Conclusion:

Our MRI algorithm produces accurate tissue quantification, is less labor‐intensive, and more reproducible than the original CT‐based workflow and can address interparticipant anatomic variability and intensity inhomogeneity effects. J. Magn. Reson. Imaging 2012;35:1152‐1161. © 2011 Wiley Periodicals, Inc.