Association between High Diffusion-Weighted Imaging-Derived Functional Tumor Burden of Peritoneal Carcinomatosis and Overall Survival in Patients with Advanced Ovarian Carcinoma

ObjectiveTo investigate the association between functional tumor burden of peritoneal carcinomatosis (PC) derived from diffusion-weighted imaging (DWI) and overall survival in patients with advanced ovarian carcinoma (OC).Materials and MethodsThis prospective study was approved by the local research ethics committee, and informed consent was obtained. Fifty patients (mean age ± standard deviation, 57 ± 12 years) with stage III–IV OC scheduled for primary or interval debulking surgery (IDS) were recruited between June 2016 and December 2021. DWI (b values: 0, 400, and 800 s/mm²) was acquired with a 16-channel phased-array torso coil. The functional PC burden on DWI was derived based on K-means clustering to discard fat, air, and normal tissue. A score similar to the surgical peritoneal cancer index was assigned to each abdominopelvic region, with additional scores assigned to the involvement of critical sites, denoted as the functional peritoneal cancer index (fPCI). The apparent diffusion coefficient (ADC) of the largest lesion was calculated. Patients were dichotomized by immediate surgical outcome into high- and low-risk groups (with and without residual disease, respectively) with subsequent survival analysis using the Kaplan-Meier curve and log-rank test. Multivariable Cox proportional hazards regression was used to evaluate the association between DWI-derived results and overall survival.ResultsFifteen (30.0%) patients underwent primary debulking surgery, and 35 (70.0%) patients received neoadjuvant chemotherapy followed by IDS. Complete tumor debulking was achieved in 32 patients. Patients with residual disease after debulking surgery had reduced overall survival (p = 0.043). The fPCI/ADC was negatively associated with overall survival when accounted for clinicopathological information with a hazard ratio of 1.254 for high fPCI/ADC (95% confidence interval, 1.007–1.560; p = 0.043).ConclusionA high DWI-derived functional tumor burden was associated with decreased overall survival in patients with advanced OC.     

用超临界流体色谱法测定怀牛膝及其制剂中齐墩果酸的含量

采用超临界流体色谱法(SFC)分别测定了不同产地的怀牛膝药材及三种含怀牛膝的制剂中齐墩果酸的含量。方法简单、快速。不需经特殊的纯化处理。各产地药材齐墩果酸含量波动较小(1.75～2.19％,x±SD=1.94±0.17％),可以作为药材与制剂质量评价的指标,药材的加样回收率为97.42％(n=18,RSD=2.80％);制剂天麻丸的加样回收率为94.82％(n=9,RSD=2.51％)。     

应用Dextroscope软件系统三维重建腰椎及其相关结构的可视化模型

目的：利用Dextroscope软件系统重建腰椎及其相关结构的可视化模型. 方法：实验于2006-11/2007-04在南方医科大学生物力学实验室完成.①实验材料：资料来源为国家863虚拟中国人项目课题组采集的“虚拟中国人女性一号”数据集.螺旋CT（Siemens Somatom Plus4型,西门子）.②实验方法：采用螺旋CT对中国女1号数字人数据集进行轴位断面扫描,扫描技术参数为电压123.0 kV,电流260.0 mA,扫描层厚1.0 mm,进床速度与层厚同步,1 mm/s,螺距为1,连续扫描.扫描范围自第10胸椎至第5腰椎.把CT数据导入Dextroscope软件系统,并转换为8-bit格式,删除图像中多余的部分,缩小数据集,调节对比度.把数据加载到虚拟现实环境中,实现CT数据的可视化,分别对腰椎、竖脊肌、腰大肌、腰方肌、腹主动脉、下腔静脉进行重建,并赋予不同的颜色.重建各部分后将其合成到一个操作界面上.③实验评估：观察脊柱及其相关结构三维重建的结果. 结果：重建的脊柱及其相关结构图像能精确显示其三维空间结构,亦能沿任一轴完成连续旋转,并可进行横断面、矢状面和冠状面及任意方位剖面的实时虚拟切割. 结论：采用Dextroscope软件重建的三维图像成功地实现腰椎及其相关结构的可视化,反映了数字人腰椎部的解剖结构.     

High Accuracy of Automatic Detection of Atrial Fibrillation Using Wavelet Transform of Heart Rate Intervals

DUVERNEY, D., et al. : High Accuracy of Automatic Detection of Atrial Fibrillation Using Wavelet Transform of Heart Rate Intervals. Permanent and paroxysmal AF is a risk factor for the occurrence and the recurrence of stroke, which can occur as its first manifestation. However, its automatic identification is still unsatisfactory. In this study, a new mathematical approach was evaluated to automate AF identification. A derivation set of 30 24-hour Holter recordings, 15 with chronic AF (CAF) and 15 with sinus rhythm (SR), allowed the authors to establish specific RR variability characteristics using wavelet and fractal analysis. Then, a validation set of 50 subjects was studied using these criteria, 19 with CAF, 16 with SR, and 15 with paroxysmal AF (PAF); and each QRS was classified as true or false sinus or AF beat. In the SR group, specificity reached 99.9%; in the CAF group, sensitivity reached 99.2%; in the PAF group, sensitivity reached 96.1%, and specificity 92.6%. However, classification on a patient basis provided a sensitivity of 100%. This new approach showed a high sensitivity and a high specificity for automatic AF detection, and could be used in screening for AF in large populations at risk.     

Atrial Natriuretic Factor Release During Exercise in Patients Successively Paced in DDD and Rate Matched Ventricular Pacing

Dual chamber pacemakers were implanted in nine patients with permanent second or third degree AV block feight had complete retrograde block). Two identical exercise tests were performed after at least 1 month after implantation. During the first test (T₁) the pacemaker was programmed to the DDD mode and heart rates were recorded every 15 to 30 seconds during exercise and 30 minutes after exercise. Following 30 minutes of rest, the implanted pacemaker was programmed to the VVT mode and driven by an external pacemaker via a skin electrode. The second exercise test (T₂) was then performed and the rate of the external pacemaker was progressively changed to reproduce exactly the rate observed during T₁ at the same exercise stress. Atrial natriuretic factor (ANF) levels were determined at rest, at regular intervals during exercise, and 30 minutes after exercise. ANF levels and release were statistically higher during rate matched ventricular, than DDD pacing. It is concluded that preservation of AV synchrony reduces ANF release induced by heart rate acceleration during exercise.     

Hippocampal glutamate-glutamine (Glx) in adults with Down syndrome: a preliminary study using in vivo proton magnetic resonance spectroscopy (1H MRS)

Background

Down syndrome (DS), or trisomy 21, is one of the most common autosomal mutations. People with DS have intellectual disability (ID) and are at significantly increased risk of developing Alzheimer’s disease (AD). The biological associates of both ID and AD in DS are poorly understood, but glutamate has been proposed to play a key role. In non-DS populations, glutamate is essential to learning and memory and glutamate-mediated excitotoxicity has been implicated in AD. However, the concentration of hippocampal glutamate in DS individuals with and without dementia has not previously been directly investigated. Proton magnetic resonance spectroscopy (¹H MRS) can be used to measure in vivo the concentrations of glutamate-glutamine (Glx). The objective of the current study was to examine the hippocampal Glx concentration in non-demented DS (DS-) and demented DS (DS+) individuals.

Methods

We examined 46 adults with DS (35 without dementia and 11 with dementia) and 39 healthy controls (HC) using ¹H MRS and measured their hippocampal Glx concentrations.

Results

There was no significant difference in the hippocampal Glx concentration between DS+ and DS-, or between either of the DS groups and the healthy controls. Also, within DS, there was no significant correlation between hippocampal Glx concentration and measures of overall cognitive ability. Last, a sample size calculation based on the effect sizes from this study showed that it would have required 6,257 participants to provide 80% power to detect a significant difference between the groups which would indicate that there is a very low likelihood of a type 2 error accounting for the findings in this study.

Conclusions

Individuals with DS do not have clinically detectable differences in hippocampal Glx concentration. Other pathophysiological processes likely account for ID and AD in people with DS.