Characterization and quantification of the triterpenoids in different parts of Xanthoceras sorbifolia by HPLC-ESI-MS

Two new triterpenoid glycosides, sorbifoside A (2) and B (3), were isolated from the husks of Xanthoceras sorbifolia along with two known saponins (1, 5). Their structures were established on the basis of 1D and 2D NMR data. A simple and sensitive assay was developed for the simultaneous determination of 6 triterpenoids (1-6, including two triterpenoid aglycones) in X. sorbifolia based on high performance liquid chromatography-mass spectrometry (HPLC-MS) coupled to an electrospray ionization (ESI) interface. The analytes were detected by positive ESI ionization mode and quantified by selected ion monitoring (SIM). All the linear regressions were acquired with r2>0.998. The precisions were evaluated by intra- and inter-day tests, and the relative standard deviation (RSD) values were within the range of 2.0-2.8% and 1.7-2.9%, respectively. The recoveries for the quantified compounds were observed over the range of 95.3-104.7% with RSD values less than 4.6%. The method developed was successfully applied for simultaneous quantification of the six triterpenoids in X. sorbifolia, and our results showed that the contents of triterpenoids in different parts of X. sorbifolia varied significantly.     

Volumetric magnetic resonance imaging of dorsal root ganglia for the objective quantitative assessment of neuron death after peripheral nerve injury

Prevention of neuron death after peripheral nerve injury is vital to regaining adequate cutaneous innervation density and quality of sensation, and while experimentally proven neuroprotective therapies exist, there lacks suitable clinical outcome measures for translational research. Axotomized dorsal root ganglia (DRG) histologically exhibit volume reduction in proportion to the amount of neuronal death within them. Hence, this study evaluated the validity of using magnetic resonance imaging (MRI) to quantify DRG volume as a proxy measure of cell death. A high-resolution 3D MRI sequence was developed for volumetric quantification of the L4 DRG in the rat sciatic nerve model. An unoperated "control" group (n=4), and a "nerve transection" group (n=6), 4 weeks after axotomy, were scanned. Accuracy and validity of the technique were evaluated by comparison with morphological quantification of DRG volume and stereological counts of surviving neurons (optical fractionator). The technique was precise (coefficient of variation=4.3%), highly repeatable (9% variability), and sensitive (mean 15.0% volume reduction in axotomized ganglia detected with statistical significance: p<0.01). MRI showed strong and highly significant correlation with morphological measures of DRG volume loss (r=0.90, p<0.001), which in turn correlated well with neuron loss (r=0.75, p<0.05). MRI similarly exhibited direct correlation with neuron loss (r=0.67, p<0.05) with consistent agreement. MRI volumetric quantification of DRG is therefore a valid in vivo measure of neuron loss. As a non-invasive, objective measure of neuronal death after nerve trauma this technique has potential as a diagnostic modality and a quantitative tool for clinical studies of neuroprotective agents.     

CT定位像扫描量化定位法的再探讨

目的：探寻一种CTCR像量化定位方法及其公式,材料与方法：使用多种类型的CT机和多种扫描野,应用量化位法及其公式,对胸部,腰椎,髋关节等部位进行量化定位扫描CR像,共计291例。结果：依据各部为CR像质量等级评定标准,对291幅不同部位的CR像进行质量评定和统计,结果显示,胸部,腰椎,髋关节甲级CR像率分别为95％,99％,98％,其CR像扫描成功率均达到100％,结论：CTCR像量化定法及其公式,它适用于国内外多种CT机型,多种扫描野和多项检查部位,能显著提高CTCR像的扫描质量,使CTCR像扫描有了一种科学的质量控制方法。     

Quantitative evaluation of periprosthetic infection by real-time polymerase chain reaction: a comparison with conventional methods

Several recent studies have demonstrated the limited accuracy of conventional culture methods for diagnosing periprosthetic infections. We have applied real-time polymerase chain reaction (PCR) assays for the rapid identification of bacteria around implants and reported its utility. However, the capability of quantification is also a useful feature of this type of assay. The aim of our study was to validate the usefulness of quantitative analyses using real-time PCR of cases with clinical periprosthetic infections in comparison with more established tests, such as C-reactive protein (CRP) levels, microbiologic cultures, and histopathology. Fifty-six joints with suspected infections were reviewed retrospectively. A universal PCR assay was used to perform the quantitative analyses. The differences in the threshold cycles between clinical samples and a negative control (?Ct) in each case were calculated. The results of the quantitative PCR assay were compared with CRP levels, microbiologic cultures, and histopathology. There was a significant correlation found between the CRP and ?Ct values. There were also significant differences found in the ?Ct values according to CRP levels, with higher CRP levels showing higher ?Ct values. Similarly, there were significant differences in the ?Ct measurements in our culture results and among our pathologic evaluations. We confirmed that quantification by universal PCR based on the ?Ct correlated with preoperative CRP levels and was associated with the microbiologic culture results and pathologic severity. This quantification method may be valuable for assessing infection severity.     

Multi-parametric quantification of tricuspid regurgitation using cardiovascular magnetic resonance: A comparison to echocardiography

BackgroundVelocity-encoding is used to quantify tricuspid regurgitation (TR) by cardiovascular magnetic resonance (CMR), but requires additional dedicated imaging. We hypothesized that size and signal intensity (SI) of the cross-sectional TR jet area in the right atrium in short-axis steady-state free-precession images could be used to assess TR severity.MethodsWe studied 61 patients with TR, who underwent CMR and echocardiography within 24 h. TR severity was determined by vena contracta: severe (N = 20), moderate or mild (N = 41). CMR TR jet area and normalized SI were measured in the plane and frame that depicted maximum area. ROC analysis was performed in 21/61 patients to determine diagnostic accuracy of differentiating degrees of TR. Optimal cutoffs were independently tested in the remaining 40 patients.ResultsMeasurable regions of signal loss depicting TR jets were noted in 51/61 patients, while 9/10 remaining patients had mild TR by echocardiography. With increasing TR severity, jet area significantly increased (15 ± 14 to 38 ± 20 mm²), while normalized SI decreased (57 ± 27 to 23 ± 11). ROC analysis showed high AUC values in the derivation group and good accuracy in the test group.ConclusionTR can be quantified from short-axis CMR images in agreement with echocardiography, while circumventing additional image acquisition.     

正常人肝脏灰阶超声造影定量研究

目的 研究正常人肝脏造影剂增强特点及其规律。 方法 对15例正常人肝脏进行SonoVue灰阶超声造影定量分析。 结果 首先肝动脉开始增强呈树枝样，随后门静脉及下腔静脉增强，最后肝静脉增强。肝动脉较门静脉、下腔静脉及肝静脉峰值时间明显提前（P〈0．001）。与后场肝实质比较，前场，中场造影剂开始增强时间和达峰值时间较早，峰值强度较强、渡越时间较长，曲线下面积较大（P〈0．05）。 结论 SonoVue的应用提高了肝内细小血管显示。对于体质量相对较高者可采用提高机械指数和局部放大提高后场造影显示。     

Improved stroke volume assessment in the aortic and mitral valves with a new method in subjects without regurgitation.

BACKGROUND: Echocardiography combining Doppler and two-dimensional data is recommended for quantitative assessments of valvular regurgitation. We applied a new method to calculate the mitral annulus (MA) area in combination with multiple sample sites. Individuals without regurgitation in whom the valvular and left ventricular stroke volumes (SV) should be identical were investigated in order to evaluate the feasibility in quantitative assessments of valvular regurgitation. METHODS AND RESULTS: Twenty subjects were included. Flow velocity was registered with pulsed Doppler in different positions in the left ventricular outflow tract (LVOT) and in the MA. The MA area was assumed to be either circular, using the diameter from a four-chamber projection, or elliptic, using the major diameter from a parasternal short axis and a minor diameter from an apical long axis. Left ventricular (LV) SV was measured from LV volumes using the biplane method. The overall difference between LVOT SV and mitral SV using one centrally located measurement and elliptic MA was 3.2+/-15.6 ml (P=0.38), 0.9+/-15.7 ml between LVOT SV and LV SV (P=0.80) and -2.2+/-15.2 ml between mitral SV and LV SV (P=0.54). The corresponding standard deviation of the differences as a percentage of the mean value was 24%, 25% and 23%. A circular shaped MA overestimated the mitral SV compared with LVOT SV (P=0.009) and LV SV (P=0.004). Increasing the number of sample sites in the LVOT or MA did not further improve the results. CONCLUSION: Doppler and two-dimensional echocardiography can be used to quantify regurgitation in groups of patients. In individual patients the wide distribution of differences between valves and LV SV implies that the method should be used in conjunction with other Doppler echocardiographic parameters.     

Quantification of Acoustic Radiation Force Impulse in Differentiating Between Malignant and Benign Breast Lesions

The aim of this study was to evaluate the use of gray-level quantification (GLQ) in virtual touch tissue imaging (VTI) in the differential diagnosis of breast lesions. GLQ values of 153 lesions (101 benign, 52 malignant) were analyzed with matrix laboratory software (MATLAB, The MathWorks, Natick, MA, USA), with gray levels ranging from 0 (pure black) to 255 (pure white). The diagnostic performance of GLQ was also evaluated using receiver operating characteristic curve analysis. The mean GLQ value for benign lesions (103.27 ± 39.44) differed significantly from that for malignant lesions (44.57 ± 13.61) (p < 0.001). At a cutoff value of 52.31, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value were 86.5%, 93.1%, 90.8%, 86.5% and 93.1%, respectively. In conclusion, we have proposed a method for quantification of gray levels in VTI for the differential diagnosis of breast lesions. Our results indicate that this method has the potential to aid in the classification of benign and malignant breast masses.