Improvement of patient localization repeatability using a light-section based optical surface guidance system in a pre-positioning procedure

PurposeSurface-guided radiotherapy is useful for the pre-positioning and monitoring of radiotherapy. The purpose of this study was to investigate the impact of surface guidance on the repeatability of patient localization and to estimate the specific point at which high positional errors occur.Materials and methodsTen patients without the VOXELAN system (non-VXLN group) and 10 patients with the VOXELAN as the pre-positioning procedure (VXLN group) were included in this analysis. Twelve regions of interest (ROI) were defined in all the patients to verify any misalignment during radiotherapy. Thirteen ROIs were defined on the isocenter.ResultsCompared with the non-VXLN group, the translational positional errors of the VXLN group were the same for all the ROIs. The mean translational positional errors of the VXLN group in the longitudinal direction were approximately 0.1 mm, and the standard deviation was the largest among the three directions in all the ROIs. The magnitude of the standard deviation in the non-VXLN group varied independently of the ROI and direction. The standard deviations of the VXLN group in the longitudinal direction were large in all the ROIs, while the standard deviations in the vertical and lateral directions were small.ConclusionPre-positioning with a surface guidance system reduced the body twist and rotation, which could not be corrected by image-guided radiotherapy alone. Since the VOXELAN can detect positioning errors quickly and without additional radiation exposure to the patient, it can be used as a tool for pre-positioning in radiotherapy.     

一测多评法在中药质量控制中的应用及研究进展＊

一测多评法（quantitative analysis of multi-components by single marker，QAMS）已成熟应用于中药材、中药提取物及中成药领域等中药复杂体系的质量评价研究中，有效解决了因对照品缺乏而导致的多指标质控技术推广难问题。本文查阅近五年的国内外研究文献，重点总结了高效液相色谱、气相色谱和质谱等技术在QAMS法中药质量控制中的应用。高效液相色谱联用紫外检测器（UV）技术应用最为广泛，最适合于中药QAMS法定量，结果稳定、准确；而高效液相色谱联用蒸发光检测器在中药QAMS法应用中，其测定准确性和适用性仍然需进一步探索和验证。液质联用技术虽然具有灵敏度高、线性范围宽等优点，但易受仪器参数、基质效应等的影响。进一步发展HPLC-UV技术在中成药制剂质量评价中的应用，是QAMS法多成分定量值得关注的方向；探索LC-MS和GC技术在中药QAMS质量评价中的稳定性和普适性是未来将面临的挑战。     

Analytical method for detection and quantification of new emerging drug etaqualone in human blood and urine by gas chromatography tandem mass spectrometry

Analytical procedure for detection and quantification of etaqualone in human blood and urine using GC–MS/MS was established and applied to authentic human samples obtained from volunteers. A liquid–liquid extraction method was employed. Each 1.0 mL of blood or urine was alkalized and extracted with diethyl ether. The solvent layer was evaporated to dryness and reconstituted with methanol then analyzed by GC–MS/MS. linear relationships within the concentration range of 1–100 ng/mL were obtained in calibrators for both blood and urine, demonstrating correlation coefficients values being>0.999. For blood and urine samples, the intra-day assay precision and accuracy values are each less than 3.65%, 7.13%, and 6.02%, 9.12%; those values of the inter-day assay are each less than 1.82%, 6.74%, and 3.99%, 7.41%. The extraction recovery rates for etaqualone ranged from 98.7% to 106%. The lower limit of quantifications was 1.0 ng/mL in both blood and urine. Stabilities of etaqualone in blood and urine were satisfactory under various temperatures within 15 days. 8.51 and 2.06 ng/mL of etaqualone in blood and urine were detected at 4 h later oral ingestion; 6.91 and 3.94 ng/mL of etaqualone were also detected 30 min and 2 h later smoking from blood and urine.     

地黄毛蕊花糖苷合酶基因的克隆、亚细胞定位与表达特性分析

目的克隆地黄Rehmanniaglutinosa毛蕊花糖苷合酶基因(Rg Ac S1),分析其亚细胞定位和表达模式。方法在地黄的转录组数据库中通过注释和比对,获得地黄Rg Ac S1的c DNA序列,利用聚合酶链式反应(PCR)方法进行分子克隆。构建绿色荧光蛋白(GFP)融合表达载体,以农杆菌瞬时表达法观测Rg Ac S1的亚细胞定位。利用实时荧光定量PCR(q RT-PCR)检测Rg Ac S1基因在地黄块根不同部位的表达模式。结果获得地黄1个莽草酸-O-羟基肉桂酰基转移酶的全长编码序列,c DNA长度为1 659 bp,包含1个1 296 bp的开放阅读框,编码431个氨基酸残基,蛋白质相对分子质量为475 900,具有莽草酸-O-羟基肉桂酰基转移酶的典型结构域,命名为Rg Ac S1。亚细胞定位结果显示Rg Ac S1主要分布在细胞质中,在细胞核中也有分布。q RT-PCR分析表明,Rg Ac S1在地黄的周皮和根毛中表达量较高,在木质部和韧皮部表达量较低。Rg Ac S1基因在地黄品种北京1号、QH1和85-5中非菊花心中表达量均高于菊花心中的表达量,且差异达极显著水平。结论获得地黄Rg Ac S1的c DNA序列,明确了Rg Ac S1的亚细胞定位和时空表达模式,为进一步研究Rg Ac S1基因在毛蕊花糖苷合成过程中的作用奠定基础。     

The impact of age on prognosis in patients with gastric cancer: experience in a tertiary care centre

BackgroundGastric cancer (GC) is a leading cause of cancer-related death in the world and most patients have advanced disease upon presentation. The effect of age on prognosis in GC is controversial. We aimed to determine the impact of age on survival in patients with GC.MethodsThis was a retrospective study of the medical records of Lebanese patients diagnosed with GC at the American University of Beirut Medical Center (AUBMC) between 2005 and 2014. Patients were divided into young (<65 years) and older groups (≥65 years). A multivariate analysis was done to determine the independent predictors of survival. Kaplan-Meier method was used for analysis of long-term survival outcomes.ResultsThe sample consisted of 156 patients. The mean age was 62.15 (SD 13.54). Most patients presented with stage 4 disease (62.2%) and poorly differentiated histology (66.4%). The most common symptoms were abdominal pain and weight loss. On bivariate analysis, advanced stage (P=0.02) and higher grade (P=0.04) were associated with increased mortality. Patients <65 years of age were significantly more likely to have poorly differentiated tumours, while patients ≥65 years had more comorbidities (P=0.001). The 5-year DFS were 35% and 37% for patients <65 years of age and ≥65 years of age, respectively (P=0.15).ConclusionsHigher grade and advanced stage are associated with worse survival in patients with GC, but age did not seem to have an impact. Screening high risk patients and early diagnosis are necessary to improve survival.     

Is the future magnetic? Magseed localisation for non palpable breast cancer. A multi-centre non randomised control study

IntroductionMagseed is an alternative method of localising non-palpable breast lesions that has addressed many of the limitations of wire guided localisation (WGL). It consists of a paramagnetic seed that can be visualised on mammography and ultrasound. Intraoperative localisation of the seed is achieved with the use of the Sentimag probe. The aim of this study was to prospectively compare localisation in patients undergoing wide local excision (WLE) for non-palpable lesions between Magseed and WGL.MethodsWe prospectively collected data on all patients undergoing image-guided WLE between October 2017 and September 2018 in two academic breast units with a planned accrual of 100 consecutive patients undergoing Magseed localisation. Data was also collected on a cohort of 100 consecutive patients undergoing WGL in the same time period.ResultsDemographic and disease characteristics were well balanced between the two groups. 4/104 patients were converted preoperatively from Magseed to WGL (2 misplaced Magseeds; 2 undetected Magseeds). Intraoperative identification and excision of the localised lesion was successful in all patients as confirmed with specimen radiography. Overall no significant differences were observed in the proportion of patients requiring re-excision between the two groups (Magseed 16% vs. WGL 14% p = 0.692). Specimens size by weight and volume was similar for both groups (Magseed 39.6 g vs. WGL 44.5 g p = 0.206 and 90.1 cm³ for Magseed vs. 95.6 cm³ for WGL p = 0.579).ConclusionsIn our series Magseed localisation proved to be as reliable and effective as WGL in terms of lesion identification, excision with tumour free margins and specimen weight.     

Spatiotemporal map of key signaling factors during early penis development

The formation of the external genitalia is a highly complex developmental process, considering it involves a wide range of cell types and results in sexually dimorphic outcomes. Development is controlled by several secreted signalling factors produced in complex spatiotemporal patterns, including the hedgehog (HH), bone morphogenic protein (BMP), fibroblast growth factor (FGF) and WNT signalling families. Many of these factors act on or are influenced by the actions of the androgen receptor (AR) that is critical to masculinisation. This complexity of expression makes it difficult to conceptualise patterns of potential importance. Mapping expression during key stages of development is needed to develop a comprehensive model of how different cell types interact in formation of external genitalia, and the global regulatory networks at play. This is particularly true in light of the sensitivity of this process to environmental disruption during key stages of development. The goal of this review is to integrate all recent studies on gene expression in early penis development to create a comprehensive spatiotemporal map. This serves as a resource to aid in visualising potentially significant interactions involved in external genital development.     

A fatal poisoning case of acetone cyanohydrin and citalopram

Acetone cyanohydrin (ACH) is a readily available source of cyanide and is widely used in basic and applied sciences. In toxicology, ACH is classified as extremely hazardous as it readily decomposes on contact with water, with the potential rapid release of highly toxic hydrogen cyanide (HCN). We report the case of a young woman found dead from the intentional ingestion of ACH and citalopram, an antidepressant of the selective serotonin reuptake inhibitor class. The autopsy findings included bright reddish-purple hypostasis and mild pulmonary edema. As ACH can decompose to acetone and HCN, we quantified the concentration of each compound and thiocyanate separately in various body fluids and organs and determined their whole-body distributions by using gas chromatography–mass spectrometry (GC–MS). We observed high concentrations of both acetone and cyanide in the blood (0.63 mg/mL and 17.99 mM, respectively) and gastric contents (9.76 mg/mL and 472.44 mM). The whole-body distributions of acetone and cyanide were similar (i.e., the concentration of each compound was the highest in the lung, followed by the heart, and then the liver). Our results suggest that not only the route of administration but also the dose taken could greatly affect the body distributions of cyanide in humans. In addition, as toxicological screening detected citalopram, which was not prescribed to the deceased, we performed a chiral analysis by using liquid chromatography–tandem mass spectrometry (LC–MS/MS). We determined that only (S)-citalopram was ingested antemortem; its concentration was 0.36 μg/mL, which is in the toxic range.     

Individualized 3D-printed templates for high-dose-rate interstitial multicathether brachytherapy in patients with breast cancer

Purpose

High-dose-rate, multicatheter interstitial brachytherapy is technically complex and operator-dependent, requiring lengthy training and specialized skills. Furthermore, until the advent of contouring on computerized tomography (CT) images, difficulties existed in locating the target volume precisely. The present article reports the results of a study that aimed at producing and validating a 3D-printed template to aid in target volume localization for multicatheter interstitial brachytherapy in patients with breast cancer.