Doxorubicin hepatotoxicity and hepatic free radical metabolism in rats. The effects of vitamin E and catechin

Doxorubicin (DXR) is an anthracycline antibiotic, broadly used in tumor therapy. In the present study we investigated whether vitamin E and catechin can reduce the toxic effects of doxorubicin. Vitamin E (200 IU/kg/week), catechin (200 mg/kg/week), doxorubicin (5 mg/kg/week), doxorubicin+vitamin E (200 IU/kg/week), doxorubicin+catechin (200 mg/kg/week) combinations were given to rats weighing 210-230 g (n=6/group). Changes in major enzymes participating in free radical metabolism superoxide dismutase (Cu,Zn-SOD), glutathione peroxidase (GSHPx), catalase (CAT) and malondialdehyde (MDA) were evaluated in the livers of all animals. Superoxide dismutase and catalase activity increased in the doxorubicin-treated group compared to control (P<0.05). Glutathione peroxidase levels increased in the catechin+doxorubicin-treated group (P<0.05) and reached maximum concentrations in the doxorubicin-treated group compared to control (P<0.01). Malondialdehyde levels increased in the doxorubicin-treated group compared to control and all-treated groups (P<0.05). Malondialdehyde, glutathione peroxidase and catalase activities were decreased in the vitamin E+doxorubicin- and catechin+doxorubicin-treated group compared to doxorubicin-treated group (P<0.05). All enzymes activities showed no statistical differences in the not mentioned groups above (P>0.05). Electron microscopic studies supported biochemical findings. We conclude that vitamin E and catechin significantly reduce doxorubicin-induced hepatotoxicity in rats.     

A formulation of tissue- and water-equivalent materials using the stoichiometric analysis method for CT-number calibration in radiotherapy treatment planning

Tissue- and water-equivalent materials (TEMs) are widely used in quality assurance and calibration procedures, both in radiodiagnostics and radiotherapy. In radiotherapy, particularly, the TEMs are often used for computed tomography (CT) number calibration in treatment planning systems. However, currently available TEMs may not be very accurate in the determination of the calibration curves due to their limitation in mimicking radiation characteristics of the corresponding real tissues in both low- and high-energy ranges. Therefore, we are proposing a new formulation of TEMs using a stoichiometric analysis method to obtain TEMs for the calibration purposes. We combined the stoichiometric calibration and the basic data method to compose base materials to develop TEMs matching standard real tissues from ICRU Report 44 and 46. First, the CT numbers of six materials with known elemental compositions were measured to get constants for the stoichiometric calibration. The results of the stoichiometric calibration were used together with the basic data method to formulate new TEMs. These new TEMs were scanned to validate their CT numbers. The electron density and the stopping power calibration curves were also generated. The absolute differences of the measured CT numbers of the new TEMs were less than 4 HU for the soft tissues and less than 22 HU for the bone compared to the ICRU real tissues. Furthermore, the calculated relative electron density and electron and proton stopping powers of the new TEMs differed by less than 2% from the corresponding ICRU real tissues. The new TEMs which were formulated using the proposed technique increase the simplicity of the calibration process and preserve the accuracy of the stoichiometric calibration simultaneously.     

早期慢性肾病患者血管内皮功能及肾脏病理相关性研究

目的：研究早期慢性肾病患者的血管内皮功能损害程度及其与肾脏病理损伤的关系。方法：60例研究对象分为3组：A组为20例正常对照组;B组为20例早期慢性肾病患者血压正常组;C组为20例早期慢性肾病患者肾性高血压组。对各组患者应用高频超声检测肱动脉充血前后管径变化率,评价早期慢性肾病患者血管内皮功能损害程度。对病例组行超声引导下穿刺活检,并对肾组织损伤程度行半定量积分,分析血管内皮功能与年龄、血压、肾脏病理损伤的关系。结果：①C组血流介导的血管舒张功能（Flow-mediated dilation,FMD）低于A组和B组（P＜0.05）,A组与B组之间FMD无差异性（P＞0.05）;②FMD与收缩压、肾小球损伤积分、肾间质损伤积分有相关性（P＜0.05）,与年龄、舒张压无相关性（P＞0.05）。结论：①肾性高血压患者在肾功能损害之前已经存在血管内皮功能的异常;②血管内皮功能紊乱对肾脏的病理损伤有一定的促进作用;③高频超声早期检测慢性肾病患者的血管内皮功能有重要的临床意义。     

Low-level laser therapy of dentin hypersensitivity: a short-term clinical trial

The aim of this study was to evaluate low-level laser therapy in cervical dentin hypersensitivity. A randomized controlled clinical trial was conducted with a total of 64 teeth. Dentin desensitizer and diode laser were applied on the cervical dentin surfaces. Distilled water and placebo laser was used as the placebo groups. The irradiance used was 4?J/cm² per treatment site. The baseline measurement of hypersensitivity was made by using visual analog scale (VAS). Twenty-four hours and 7?days after the application of desensitizer, diode laser and placebo groups, a new VAS analysis was conducted for the patients?? sensitivity level. The mean pain scores of placebo groups were significantly higher than the desensitizer??s and diode laser??s mean scores (ANOVA, p?<?0.05). The VAS analysis revealed a significant decrease in dentin hypersensitivity in 7?days with the use of the desensitizer and low-level laser therapy and no statistically significant difference was observed between these two treatments (p?>?0.05). Although low-level laser and glutaraldehyde containing desensitizer present distinct modes of action, experimental agents caused a significant reduction of dentin hypersensitivity without showing secondary effects, not irritating the pulp or causing pain, not discoloring or staining the teeth, and not irritating the soft tissues at least for a period of 1?week with no drawbacks regarding handling and/or ease of application. Low-level laser therapy and desensitizer application had displayed similar effectiveness in reducing moderate dentin hypersensitivity.     

Pulsed Electromagnetic Fields in the treatment of fresh scaphoid fractures. A multicenter,prospective, double blind,placebo controlled,randomized trial

Background  

The scaphoid bone is the most commonly fractured of the carpal bones. In the Netherlands 90% of all carpal fractures is a fracture of the scaphoid bone. The scaphoid has an essential role in functionality of the wrist, acting as a pivot. Complications in healing can result in poor functional outcome. The scaphoid fracture is a troublesome fracture and failure of treatment can result in avascular necrosis (up to 40%), non-union (5-21%) and early osteo-arthritis (up to 32%) which may seriously impair wrist function. Impaired consolidation of scaphoid fractures results in longer immobilization and more days lost at work with significant psychosocial and financial consequences.     

于氨双唑钠对局部晚期非小细胞肺癌放射增敏作用的疗效观察

目的：探讨甘氨双唑钠（CMNa）对III期肺癌的放射增敏作用及不良反应。方法：采用随机分组的方法将经病理学确诊的Ⅲ期非小细胞肺癌（NSCLC）患者分为实验组（A组,放疗加甘氨双唑钠）及对照组（B组,单纯放疗）。两组放疗方法均一样。A组在放疗同时,加用CMNa（800mg／m^2）,每周3次,至疗程结束;B组为单纯放疗,评价两组疗效及观察不良反应。结果：A组的CR＋PR为82．6％（19／23）,显著高于B组的52．2％（12／23）,P〈0．05,差异有统计学意义。两组的不良反应比较,P〉0．05,差异无统计学意义。结论：甘氨双唑钠对局部晚期非小细胞肺癌有放射增敏作用．可提高有效率（CR＋PR）,但不增加不良反应。     

不同标准空腹血糖受损人群葡萄糖负荷后血糖代谢特征

目的：分析两种标准空腹血糖受损人群葡萄糖负荷后血糖代谢特点。方法：对3828名40岁以上居民进行流行病学调查,对空腹血糖≥5.6mmol/L者行75g葡萄糖负荷试验,据不同空腹血糖受损诊断标准分析负荷后2h血糖代谢情况。结果：在以空腹血糖为6.1mmol/L为切点诊断的245例空腹血糖受损（IFG）人群中,糖耐量减低（IGT）的患病率为41.22%,女性（25.71%）高于男性（15.51%）;2型糖尿病（T2DM）患病率为20.82%,女性（11.84%）高于男性（8.98%）。在以空腹血糖为5.6mmol/L为切点诊断的627例空腹血糖受损人群中,糖耐量减低的患病率为37.00%,女性（23.76%）高于男性（13.23%）;2型糖尿病患病率为13.88%,女性（9.52%）高于男性（4.63%）。结论：以空腹血糖为5.6mmol/L和6.1mmol/L为切点诊断的空腹血糖受损人群葡萄糖负荷后2h血糖代谢异常率分别为50.88%和62.04%,患病率女性均高于男性。     

Multithreaded cardiac CT

Phase-correlated CT, as it is used for cardiac imaging, is the most popular and the most important but also the most demanding special CT application in the clinical routine, today. Basically, it fulfills the four-dimensional imaging task of depicting a quasiperiodically moving object at any desired motion phase with significantly reduced motion artifacts. Although image quality with phase-correlated reconstruction is far better than with standard reconstruction, there are motion artifacts remaining and improvements of temporal resolution are required. As a well-known alternative to simply decreasing rotation time, we consider a spiral cone-beam CT scanner that has G x-ray guns and detectors mounted. We call this a multisource or a multithreaded CT scanner. Aiming for improved temporal resolution the relative temporal resolution tau, which measures the fraction of a motion period that enters the image, is studied as a function of the motion rate (heart rate) and the degree of scan overlap (pitch value) for various configurations. The parameters to optimize are the number of threads G and the interthread parameters delta alpha and delta z, which are the angular and the longitudinal separation between adjacent threads, respectively. To demonstrate the improvements approximate image reconstruction of multithreaded raw data is performed by using a generalization of the extended parallel back projection cone-beam reconstruction algorithm [Med. Phys. 31(6), 1623-1641 (2004)] to the case of multithreaded CT. Reconstructions of a simulated cardiac motion phantom and of simulated semi-antropomorphic phantoms are presented for two and three threads and compared to the single-threaded case to demonstrate the potential of multithreaded cardiac CT. Patient data were acquired using a clinical double-threaded CT scanner to validate the theoretical results. The optimum angle delta alpha between the tubes is 90 degrees for a double-threaded system, and for triple-threaded scanners it is 60 degrees or 120 degrees. In all cases, delta z = 0 results as an optimum, which means that the threads should be mounted in the same transversal plane. However, the dependency of the temporal resolution on delta z is very weak and a longitudinal separation delta z not = 0 would not deteriorate image quality. The mean temporal resolution achievable with an optimized multithreaded CT scanner is a factor of G better than the mean temporal resolution obtained with a single-threaded scanner. The standard reconstructions showed decreased cone-beam artifacts with multithreaded CT compared to the single-threaded case. Our phase-correlated reconstructions demonstrate that temporal resolution is significantly improved with multithreaded CT. The clinical patient data confirm our results.